Startup, Commissioning and Operation of Fenyi 100MW CFB Boiler

NASA Astrophysics Data System (ADS)

Wang, Zhiwei; Yu, Wugao; Bo, Shi

The first 100MW CFB boiler, designed by the Thermal Power Research Institute and manufactured by Harbin Boiler Company Limited, has been successfully running in Jiangxi Fenyi Power Plant since 2003. Local high ash content anthracite and lean coal that are very difficult to burn out are used in the 100 MW CFB boiler. The results of the 100MW CFB boiler shows that the CFB boiler can run in 30% MCR and startup with two under bed burners, and the boiler efficiency higher than 88% can be got after the combustion modification test. The CFB boiler can be operated with full load and reaches design parameters. The emissions of NO, N2O and CO are less than 7Omg/m3, 30mg/m3, and 125mg/m3, respectively, and SO2 less than 400mg/m3 after limestone injection. The bottom ash temperature from bed ash coolers is less than 120°C after its modification. Coal blockage at the coal storage silo is the main problem influencing the CFB boiler continuous operation. The running experiences for 5 years proved that the CFB boiler performance is successful, and the results were applied in 210 MW and 330 MW CFB Boiler design of Fenyi Power Plant.

The application of ceramsite ecological floating bed in aquaculture: its effects on water quality, phytoplankton, bacteria and fish production.

PubMed

Li, Xiao-Li; Marella, Thomas Kiran; Tao, Ling; Dai, Li-Li; Peng, Liang; Song, Chao-Feng; Li, Gu

2018-06-01

In recent years, biological floating bed technology has been applied increasingly in aquaculture ponds. In this study we developed a novel floating bed made from ceramsite and studied its effect on water quality, phytoplankton, bacteria and fish growth. Water quality was effectively regulated and controlled in ceramsite floating bed (CFB) ponds with an average transparency of 23.18 cm, ammonia nitrogen (NH 4 + -N) of 2.30 mg L -1 , total nitrogen (TN) of 5.09 mg L -1 and total phosphate (TP) of 1.32 mg L -1 which are lower than in control ponds without CFB. Increased phytoplankton species diversity, bacterial number, metabolic activity and microbial diversity was observed with CFB. At the end of growth stage, feed conversion ratio (FCR) was reduced with a total fish yield of 14,838 kg ha -1 at a survival rate of 77.2% in CFB ponds, which is significantly higher than control (P < 0.05). These results emphasize the potential of ecological floating bed to improve water quality, microalgal diversity, reduce the risk of harmful algal blooms and increase the number, activity and diversity of microorganisms as well as fish yield.

Study of Nox Emission Characteristics of a 1025t/h Coal-Fired Circulating Fluidized Bed Boiler

NASA Astrophysics Data System (ADS)

Li, Q. Y.; Mi, Z. D.; Zhang, Q. F.

Measurements of emission are carried out in a 1025t/h CFB boiler. The effect of some factors including coal properties, bed temperature, unit load, excess air on the emission of NOx are investigated. The measurement results show that the N concentration in the coal is dominant parameter to predict the NOx emission from a large-scale CFB boiler. NOx emission from the 1025t/h CFB boiler increases with cyclone temperature and upper pressure drop due to post combustion and external cycle.

Application of CFB technology for large power generating units and CO{sub 2} capture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ryabov, G. A., E-mail: georgy.ryabov@gmail.com; Folomeev, O. M.; Sankin, D. A.

2010-07-15

Data on the development of the circulating fluidized bed (CFB) technology for combustion of fuels in large power generating units are examined. The problems with raising the steam parameters and unit power of boilers with a circulating fluidized bed are examined. With the boiler system at the 460 MW unit at Lagisza (Poland) as an example, the feasibility of raising the efficiency of units with CFB boilers through deep recovery of the heat of the effluent gases and reducing expenditure for in-house needs is demonstrated. Comparative estimates of the capital and operating costs of 225 and 330 MW units aremore » used to determine the conditions for optimum use of CFB boilers in the engineering renovation of thermal power plants in Russia. New areas for the application of CFB technology in CO{sub 2} capture are analyzed in connection with the problem of reducing greenhouse gas emissions.« less

Design assessment of a 150 kWt CFBC Test Unit

DOE Office of Scientific and Technical Information (OSTI.GOV)

Batu, A.; Selcuk, N.; Kulah, G.

2010-04-15

For clean and efficient energy generation from coal, the most suitable technology known to date is 'Fluidized Bed Combustion' technology. Applications of circulating fluidized bed (CFB) combustion technology have been steadily increasing in both capacity and number over the past decade. Designs of these units have been based on the combustion tests carried out in pilot scale facilities to determine the combustion and desulfurization characteristics of coal and limestone reserves in CFB conditions. Similarly, utilization of Turkish lignites in CFB boilers necessitates adaptation of CFB combustion technology to these resources. However, the design of these test units are not basedmore » on firing coals with high ash, volatile matter and sulfur contents like Turkish lignites. For this purpose, a 150 kWt CFB combustor test unit is designed and constructed in Chemical Engineering Department of Middle East Technical University, based on the extensive experience acquired at the existing 0.3 MWt Bubbling Atmospheric Fluidized Bed Combustor (AFBC) Test Rig. Following the commissioning tests, a combustion test is carried out for investigation of combustion characteristics of Can lignite in CFB conditions and for assessment of the design of test unit. Comparison of the design outputs with experimental results reveals that most of the predictions and assumptions have acceptable agreement with the operating conditions. In conclusion, the performance of 150 kWt CFBC Test Unit is found to be satisfactory to be utilized for the long term research studies on combustion and desulfurization characteristics of indigenous lignite reserves in circulating fluidized bed combustors. (author)« less

A comparison of fuzzy logic and cluster renewal approaches for heat transfer modeling in a 1296 t/h CFB boiler with low level of flue gas recirculation

NASA Astrophysics Data System (ADS)

Błaszczuk, Artur; Krzywański, Jarosław

2017-03-01

The interrelation between fuzzy logic and cluster renewal approaches for heat transfer modeling in a circulating fluidized bed (CFB) has been established based on a local furnace data. The furnace data have been measured in a 1296 t/h CFB boiler with low level of flue gas recirculation. In the present study, the bed temperature and suspension density were treated as experimental variables along the furnace height. The measured bed temperature and suspension density were varied in the range of 1131-1156 K and 1.93-6.32 kg/m3, respectively. Using the heat transfer coefficient for commercial CFB combustor, two empirical heat transfer correlation were developed in terms of important operating parameters including bed temperature and also suspension density. The fuzzy logic results were found to be in good agreement with the corresponding experimental heat transfer data obtained based on cluster renewal approach. The predicted bed-to-wall heat transfer coefficient covered a range of 109-241 W/(m2K) and 111-240 W/(m2K), for fuzzy logic and cluster renewal approach respectively. The divergence in calculated heat flux recovery along the furnace height between fuzzy logic and cluster renewal approach did not exceeded ±2%.

Multi-stage circulating fluidized bed syngas cooling

DOEpatents

Liu, Guohai; Vimalchand, Pannalal; Guan, Xiaofeng; Peng, WanWang

2016-10-11

A method and apparatus for cooling hot gas streams in the temperature range 800.degree. C. to 1600.degree. C. using multi-stage circulating fluid bed (CFB) coolers is disclosed. The invention relates to cooling the hot syngas from coal gasifiers in which the hot syngas entrains substances that foul, erode and corrode heat transfer surfaces upon contact in conventional coolers. The hot syngas is cooled by extracting and indirectly transferring heat to heat transfer surfaces with circulating inert solid particles in CFB syngas coolers. The CFB syngas coolers are staged to facilitate generation of steam at multiple conditions and hot boiler feed water that are necessary for power generation in an IGCC process. The multi-stage syngas cooler can include internally circulating fluid bed coolers, externally circulating fluid bed coolers and hybrid coolers that incorporate features of both internally and externally circulating fluid bed coolers. Higher process efficiencies can be realized as the invention can handle hot syngas from various types of gasifiers without the need for a less efficient precooling step.

Integration of concentrated solar power (CSP) and circulating fluidized bed (CFB) power plants - final results of the COMBO-CFB project

NASA Astrophysics Data System (ADS)

Suojanen, Suvi; Hakkarainen, Elina; Kettunen, Ari; Kapela, Jukka; Paldanius, Juha; Tuononen, Minttu; Selek, Istvan; Kovács, Jenö; Tähtinen, Matti

2017-06-01

Hybridization of solar energy together with another energy source is an option to provide heat and power reliably on demand. Hybridization allows decreasing combustion related fuel consumption and emissions, assuring stable grid connection and cutting costs of concentrated solar power technology due to shared power production equipment. The research project "Integration of Concentrated Solar Power (CSP) and Circulating Fluidized Bed (CFB) Power Plants" (COMBO-CFB) has been carried out to investigate the technical possibilities and limitations of the concept. The main focus was on the effect of CSP integration on combustion dynamics and on the joint power cycle, and on the interactions of subsystems. The research provides new valuable experimental data and knowhow about dynamic behaviour of CFB combustion under boundary conditions of the hybrid system. Limiting factors for maximum solar share in different hybridization schemes and suggestions for enhancing the performance of the hybrid system are derived.

CFB: technology of the future?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blankship, S.

2008-02-15

Fuel flexibility and a smaller carbon footprint are behind renewed interest in circulating fluidized bed (CFB) technology. The article explains the technology of CFB and discusses development of CFB units since the late 1990s. China is seeing an explosion in the number of utility-size CFBs. Alstom, Foster Wheeler, Babcock and Wilson and Alex Kvaener are today's major CFB boiler manufacturers. Alstom is testing and developing oxy-firing and post-combustion carbon capture strategies on CFB boilers. One CFB asset is its ability to burn a variety of fuels including waste coal, high sulfur coal and even discarded tires. The article mentions successfulmore » CFB projects at the Seward Station using waste coal and at the Gilbert 3 plant in the USA. Lamar is converting its Light and Power Plant from natural gas to burn coal in a 38.5 MW CFB boiler. 1 tab., 3 photos.« less

Heat Transfer Coefficient Distribution in the Furnace of a 300MWe CFB Boiler

NASA Astrophysics Data System (ADS)

Zhang, P.; Lu, J. F.; Yang, H. R.; Zhang, J. S.; Zhang, H.; Yue, G. X.

Properly understanding and calculating the distributions of heat flux and heat transfer coefficient (α) in the furnace is important in designing a circulating fluidized bed (CFB) boiler, especially with supercritical parameters. Experimental study on the heat transfer in a commercial 300MWe CFB boiler was conducted. The α from the bed to the water wall was measured by the finite element method (FEM), at five different heights. The influence of suspension density and bed temperature on α was analyzed. It was found that the pressure difference between the inlet and exit of the three cyclones, and the chamber pressure of the corresponding loop seal were not equal. The results indicated the suspension solid density was non-uniform in the cross section at a certain height. Consequently, the distributions of heat flux and α in the horizontal plane in the furnace was non-uniform. The furnace can divided into three sections according to the arrangement of the platen superheaters hanging in the upper CFB furnace. In each section, the heat flux near the center showed increasing trend.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mutanen, K.I.

Development of fluidized bed combustion (FBC) was started both in North America and in Europe in the 1960`s. In Europe and especially in Scandinavia the major driving force behind the development was the need to find new more efficient technologies for utilization of low-grade fuels like different biomasses and wastes. Both bubbling fluidized bed (BFB) and circulating fluidized bed (CFB) technologies were under intensive R&D,D efforts and have now advanced to dominating role in industrial and district heating power plant markets in Europe. New advanced CFB designs are now entering the markets. In North America and especially in the USmore » the driving force behind the FBC development was initially the need to utilize different types of coals in a more efficient and environmentally acceptable way. The present and future markets seem to be mainly in biomass and multifuel applications where there is benefit from high combustion efficiency, high fuel flexibility and low emissions such as in the pulp and paper industry. The choice between CFB technology and BFB technology is based on selected fuels, emission requirements, plant size and on technical and economic feasibility. Based on Scandinavian experience there is vast potential in the North American industry to retrofit existing oil fired, pulverized coal fired, chemical recovery or grate fired boilers with FBC systems or to build a new FBC based boiler plant. This paper will present the status of CFB technologies and will compare technical and economic feasibility of CFB technology to CFB technology to BFB and also to other combustion methods. Power plant projects that are using advanced CFB technology e.g. Ahlstrom Pyroflow Compact technology for biomass firing and co-firing of biomass with other fuels will also be introduced.« less

Gas flow through through a porous mantle: implications of fluidisation

NASA Astrophysics Data System (ADS)

Bentley, Mark; Koemle, Norbert; Kargl, Guenter; Huetter, Mag. Erika Sonja

Understanding the interaction of dust and gas in the upper layers of a cometary mantle is critical for understanding cometary evolution. The state of knowledge of conditions in these layers is currently rather low, and a wide range of flow conditions and phenomena can be imagined. A model is presented here that examines the conditions under which so-called "fluidized beds" might be possible in a cometary mantle. This phenomenon, well studied in industry, occurs when the weight of a bed of particles is equal to the gas drag of a gas or fluid flowing upwards through it. Wherever fluidisation occurs in a cometary mantle, it could change the dominant heat transfer mechanism by removing intimate particle contacts (creating an expanded bed) or allowing particle convection in the now fluid-like mantle. There are also implications for the stability of the Rosetta lander, Philae, if such a state were to occur in the vicinity of the deployed anchor. A two-fluid model is used, with necessarily restricted geometries, to demonstrate the conditions (gravity, pressure, gas velocity, particle size etc.) under which fluidisation could occur, and the scientific results and implications for the Rosetta mission are explored.

Bed inventory overturn in a circulating fluid bed riser with pant-leg structure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jinjing Li; Wei Wang; Hairui Yang

2009-05-15

The special phenomenon, nominated as bed inventory overturn, in circulating fluid bed (CFB) riser with pant-leg structure was studied with model calculation and experimental work. A compounded pressure drop mathematic model was developed and validated with the experimental data in a cold experimental test rig. The model calculation results agree well with the measured data. In addition, the intensity of bed inventory overturn is directly proportional to the fluidizing velocity and is inversely proportional to the branch point height. The results in the present study provide significant information for the design and operation of a CFB boiler with pant-leg structure.more » 15 refs., 10 figs., 1 tab.« less

Dispersion modelling and measurement of emissions from the co-combustion of meat and bone meal with peat in a fluidised bed.

PubMed

Cummins, Enda J; McDonnell, Kevin P; Ward, Shane M

2006-05-01

Due to the ban on meat and bone meal (MBM) as an animal feed, combustion with energy recovery has been considered a viable alternative usage for the mounting stocks of MBM. The effects of the co-combustion of MBM and peat on flue gas emissions and fluidisation were studied using a bubbling fluidised bed (BFB) test facility (20 kW). The dispersion of emissions such as nitrogen dioxide (NO2), sulphur dioxide (SO2), carbon monoxide (CO), hydrogen chloride (HCl) and particulates was investigated for a proposed site and compared to the relevant national and international regulations. Concentrations of NO2, CO and HCl were less than 10% of legislative and guideline thresholds while ground level concentrations of SO2 were also below relevant EU and world guidelines. The results indicate the potential for using MBM as a co-fuel with peat in a BFB while maintaining high air quality standards.

Mathematical modelling of sewage sludge incineration in a bubbling fluidised bed with special consideration for thermally-thick fuel particles.

PubMed

Yang, Yao Bin; Sharifi, Vida; Swithenbank, Jim

2008-11-01

Fluidised bed combustor (FBC) is one of the key technologies for sewage sludge incineration. In this paper, a mathematical model is developed for the simulation of a large-scale sewage sludge incineration plant. The model assumes the bed consisting of a fast-gas phase, an emulsion phase and a fuel particle phase with specific consideration for thermally-thick fuel particles. The model further improves over previous works by taking into account throughflow inside the bubbles as well as the floating and random movement of the fuel particles inside the bed. Validation against both previous lab-scale experiments and operational data of a large-scale industrial plant was made. Calculation results indicate that combustion split between the bed and the freeboard can range from 60/40 to 90/10 depending on the fuel particle distribution across the bed height under the specific conditions. The bed performance is heavily affected by the variation in sludge moisture level. The response time to variation in feeding rate is different for different parameters, from 6 min for outlet H2O, 10 min for O2, to 34 min for bed temperature.

Improving Drinking Water Quality by Remineralisation.

PubMed

Luptáková, Anna; Derco, Ján

2015-01-01

The reason of low mineral content in source water is its origin in poorly soluble mineral geological structures. There are many areas with very soft low-mineralised water around the world. All people involved in drinking water treatment as well as some public health experts and producers of chemicals used for water treatment may be interested in the study. Enrichment of drinking water by minerals including calcium and magnesium is very important particularly in regions where drinking water is prepared by desalination. The aim of this work was to study and intensify the recarbonization process. Half-calcined dolomite in combination with carbon dioxide constitutes the chemistry of the applied method. Advantages of using a fluidised bed reactor contributed also significantly to the process efficiency enhancement. Continuous input of carbon dioxide into the fluidised bed recarbonization reactor resulted in an increase in the recarbonization rate by about one order of magnitude compared with the process in without carbon dioxide addition. Very good fit of experimental data for hydrodynamic characteristics of fluidised bed was obtained using simple model based on the Richardson and Zaki expansion equation. The first order model describes kinetic data from the recarbonization process with a good accuracy. Higher recarbonization rates were observed with smaller particles of half-calcined dolomite.

Principles of an enhanced MBR-process with mechanical cleaning.

PubMed

Rosenberger, S; Helmus, F P; Krause, S; Bareth, A; Meyer-Blumenroth, U

2011-01-01

Up to date, different physical and chemical cleaning protocols are necessary to limit membrane fouling in membrane bioreactors. This paper deals with a mechanical cleaning process, which aims at the avoidance of hypochlorite and other critical chemicals in MBR with submerged flat sheet modules. The process basically consists of the addition of plastic particles into the loop circulation within submerged membrane modules. Investigations of two pilot plants are presented: Pilot plant 1 is equipped with a 10 m(2) membrane module and operated with a translucent model suspension; pilot plant 2 is equipped with four 50 m(2) membrane modules and operated with pretreated sewage. Results of pilot plant 1 show that the establishment of a fluidised bed with regular particle distribution is possible for a variety of particles. Particles with maximum densities of 1.05 g/cm(3) and between 3 and 5 mm diameter form a stable fluidised bed almost regardless of activated sludge concentration, viscosity and reactor geometry. Particles with densities between 1.05 g/cm(3) and 1.2 g/cm(3) form a stable fluidised bed, if the velocity at the reactor bottom is sufficiently high. Activities within pilot plant 2 focused on plant optimisation and the development of an adequate particle retention system.

Phase shift method to estimate solids circulation rate in circulating fluidized beds

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ludlow, James Christopher; Panday, Rupen; Shadle, Lawrence J.

2013-01-01

While solids circulation rate is a critical design and control parameter in circulating fluidized bed (CFB) reactor systems, there are no available techniques to measure it directly at conditions of industrial interest. Cold flow tests have been conducted at NETL in an industrial scale CFB unit where the solids flow has been the topic of research in order to develop an independent method which could be applied to CFBs operating under the erosive and corrosive high temperatures and pressures of a coal fired boiler or gasifier. The dynamic responses of the CFB loop to modest modulated aeration flows in themore » return leg or standpipe were imposed to establish a periodic response in the unit without causing upset in the process performance. The resulting periodic behavior could then be analyzed with a dynamic model and the average solids circulation rate could be established. This method was applied to the CFB unit operated under a wide range of operating conditions including fast fluidization, core annular flow, dilute and dense transport, and dense suspension upflow. In addition, the system was operated in both low and high total solids inventories to explore the influence of inventory limiting cases on the estimated results. The technique was able to estimate the solids circulation rate for all transport circulating fluidized beds when operating above upper transport velocity, U{sub tr2}. For CFB operating in the fast fluidized bed regime (i.e., U{sub g}< U{sub tr2}), the phase shift technique was not successful. The riser pressure drop becomes independent of the solids circulation rate and the mass flow rate out of the riser does not show modulated behavior even when the riser pressure drop does.« less

Industrial Application Study on New-Type Mixed-Flow Fluidized Bed Bottom Ash Cooler

NASA Astrophysics Data System (ADS)

Zeng, B.; Lu, X. F.; Liu, H. Z.

As a key auxiliary device of CFB boiler, the bottom ash cooler (BAC) has a direct influence on secure and economic operation of the boiler. The operating situation of domestic CFB power plant is complex and changeable with a bad coal-fired condition. The principle for designing BAC suitable for the bad coal-fired condition and high parameter CFB boilers was summarized in this paper. Meanwhile, a new-type mixed-flow fluidized bed bottom ash cooler was successfully designed on the basis of the comprehensive investigation on the existing BAC s merits and drawbacks. Using coarse/fine slag separation technology and micro-bubbling fluidization are the significant characteristics of this new BAC. This paper also puts great emphasis on its industrial test in a 460t/h CFB boiler. The results indicate that it achieves significant separation of the coarse/fine slag, an obvious cooling effect, no slag block and coking phenomenon, and continuous stable operation. Figs 7, Tabs 4 and Refs 11.

Effects of the updated national emission regulation in China on circulating fluidized bed boilers and the solutions to meet them.

PubMed

Li, Jingji; Yang, Hairui; Wu, Yuxin; Lv, Junfu; Yue, Guangxi

2013-06-18

The advantage of circulating fluidized bed (CFB) boilers in China is their ability to utilize low rank coal with low cost emission control. However, the new National Emission Regulation (NER) issued in early 2012 brings much more stringent challenges on the CFB industries, which also causes much attention from other countries. Based on the principle of a CFB boiler and previous operating experience, it is possible for the CFB boilers to meet the new NER and maintain the advantage of low cost emission control, while, more influences should be considered in their design and operation. To meet the requirement of the new NER, the fly ash collector should adopt a bag house or combination of electrostatic precipitator and bag filter to ensure dust emissions of less than 30 mg · Nm(-3). For SO2 emission control, the bed temperature should be strictly lower than 900 °C to maintain high reactivity and pores. The limestone particle size distribution should be ranged within a special scope to optimize the residence time and gas-solid reaction. At the same time, the injecting point should be optimized to ensure fast contact of lime with oxygen. In such conditions, the desulfurization efficiency could be increased more than 90%. For lower sulfur content fuels (<1.5%, referred value based on the heating value of standard coal of China), increasing Ca/S enough could decrease SO2 emissions lower than that of the new NER, 100 mg · Nm(-3). For fuels with sulfur content higher than 1.5%, some simplified systems for flue gas desulfurization, such as flash dryer absorber (FDA), are needed. And the NOx emissions of a CFB can be controlled to less than 100 mg · Nm(-3) without any equipment at a bed temperature lower than 900 °C for fuels with low volatiles content (<12%), while for fuels with high volatiles, selective non-catalytic reduction (SNCR) should be considered. Due to the unique temperature in CFB as well as the circulating ash, the efficiency of SNCR could reach as high as 70%. The Hg emission of CFB is very low for the new NER due to its innate property.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rode, J.R.; Brzezeina, P.; Strach, F.

This paper discusses the engineering considerations related to the design of a new 110 MWe atmospheric fluidized bed boiler (CFB) and boiler island auxiliaries for installation at the CEZ, a.s. (Czech Republic Utility) Ledvice Power Station. The plant is located in the northwest Bohemia area of the Czech Republic in the foothills of the Krusne Hory Mountains, between the towns of Bilina and Teplice. The type of fuel to be burned in the CFB is brown coal which requires unique design considerations in as well as the particular boiler operational parameters. The impetus behind the addition of this new CFBmore » at the plant is that the existing pulverized coal fired steam generator which was put in service in 1969 is unable to meet new regulations and laws regarding compliance with the protection of the environment and will be replaced once the new CFB unit is brought into service. A technical-economic study conducted by CEZ, a.s. evaluated CFB technology as the most advantageous from a long-term standpoint. The following variations were considered in the study: boiler retrofit and construction of new ash handling equipment; implementation of the combined cycle based upon natural gas; and reconstruction of the boiler equipment with transition to atmospheric fluid-bed combustion. The selection of the supplier of fluid-bed boiler was performed with an emphasis of the bidders` references as for the construction and operation of fluid-bed boilers with the outputs of min. 300 t/hr.« less

Fluidised bed catalytic pyrolysis of scrap tyres: influence of catalyst:tyre ratio and catalyst temperature.

PubMed

Williams, Paul T; Brindle, Alexander J

2002-12-01

Pyrolysis with on-line Zeolite catalysis of scrap tyres was undertaken in a fluidised bed reactor with the aim of maximising the production of higher value single ring aromatic hydrocarbons in the derived oil. Experiments were carried out in relation to the ratio of the catalyst to tyre feedstock and the temperature of the catalyst bed. Two Zeolite catalysts were examined, a Y-type Zeolite catalyst and Zeolite ZSM-5 catalyst of differing pore size and surface activity. The composition of the oils derived from the uncatalysed fluidised bed pyrolysis of tyres showed that benzene concentration was 0.2 wt%, toluene concentration was 0.8 wt%, o-xylene was 0.3 wt%, m/p-xylenes were 1.8 wt% and limonene was 4.3 wt%. Benzene, toluene and xylenes present in the oils showed a significant increase in the presence of both of the catalysts. The maximum concentrations of these chemicals for the Y-Zeolite (CBV-400) catalyst was 1 wt% for benzene, 8wt% for toluene, 3 wt% for o-xylene and 8.5 wt% for m/p-xylenes, produced at a catalyst:tyre ratio of 1.5. There was less influence of catalyst temperature on the yield of benzene, toluene and xylenes, however, increasing the temperature of the catalyst resulted in a marked decrease in limonene concentration. The Y-type Zeolite catalyst produced significantly higher concentrations of benzene, toluene and xylenes which was attributed to the larger pore size and higher surface acidity of the Y-Zeolite catalyst compared to the Zeolite ZSM-5 catalyst.

Effect of particle size distribution on the hydrodynamics of dense CFB risers

NASA Astrophysics Data System (ADS)

Bakshi, Akhilesh; Khanna, Samir; Venuturumilli, Raj; Altantzis, Christos; Ghoniem, Ahmed

2015-11-01

Circulating Fluidized Beds (CFB) are favorable in the energy and chemical industries, due to their high efficiency. While accurate hydrodynamic modeling is essential for optimizing performance, most CFB riser simulations are performed assuming equally-sized solid particles, owing to limited computational resources. Even though this approach yields reasonable predictions, it neglects commonly observed experimental findings suggesting the strong effect of particle size distribution (psd) on the hydrodynamics and chemical conversion. Thus, this study is focused on the inclusion of discrete particle sizes to represent the psd and its effect on fluidization via 2D numerical simulations. The particle sizes and corresponding mass fluxes are obtained using experimental data in dense CFB riser while the modeling framework is described in Bakshi et al 2015. Simulations are conducted at two scales: (a) fine grid to resolve heterogeneous structures and (b) coarse grid using EMMS sub-grid modifications. Using suitable metrics which capture bed dynamics, this study provides insights into segregation and mixing of particles as well as highlights need for improved sub-grid models.

Static and transient performance prediction for CFB boilers using a Bayesian-Gaussian Neural Network

NASA Astrophysics Data System (ADS)

Ye, Haiwen; Ni, Weidou

1997-06-01

A Bayesian-Gaussian Neural Network (BGNN) is put forward in this paper to predict the static and transient performance of Circulating Fluidized Bed (CFB) boilers. The advantages of this network over Back-Propagation Neural Networks (BPNNs), easier determination of topology, simpler and time saving in training process as well as self-organizing ability, make this network more practical in on-line performance prediction for complicated processes. Simulation shows that this network is comparable to the BPNNs in predicting the performance of CFB boilers. Good and practical on-line performance predictions are essential for operation guide and model predictive control of CFB boilers, which are under research by the authors.

MFIX simulation of NETL/PSRI challenge problem of circulating fluidized bed

DOE PAGES

Li, Tingwen; Dietiker, Jean-François; Shahnam, Mehrdad

2012-12-01

In this paper, numerical simulations of NETL/PSRI challenge problem of circulating fluidized bed (CFB) using the open-source code Multiphase Flow with Interphase eXchange (MFIX) are reported. Two rounds of simulation results are reported including the first-round blind test and the second-round modeling refinement. Three-dimensional high fidelity simulations are conducted to model a 12-inch diameter pilot-scale CFB riser. Detailed comparisons between numerical results and experimental data are made with respect to axial pressure gradient profile, radial profiles of solids velocity and solids mass flux along different radial directions at various elevations for operating conditions covering different fluidization regimes. Overall, the numericalmore » results show that CFD can predict the complex gas–solids flow behavior in the CFB riser reasonably well. In addition, lessons learnt from modeling this challenge problem are presented.« less

Model-free adaptive control of advanced power plants

DOEpatents

Cheng, George Shu-Xing; Mulkey, Steven L.; Wang, Qiang

2015-08-18

A novel 3-Input-3-Output (3.times.3) Model-Free Adaptive (MFA) controller with a set of artificial neural networks as part of the controller is introduced. A 3.times.3 MFA control system using the inventive 3.times.3 MFA controller is described to control key process variables including Power, Steam Throttle Pressure, and Steam Temperature of boiler-turbine-generator (BTG) units in conventional and advanced power plants. Those advanced power plants may comprise Once-Through Supercritical (OTSC) Boilers, Circulating Fluidized-Bed (CFB) Boilers, and Once-Through Supercritical Circulating Fluidized-Bed (OTSC CFB) Boilers.

Dry formulations of the biocontrol agent Candida sake CPA-1 using fluidised bed drying to control the main postharvest diseases on fruits.

PubMed

Carbó, Anna; Torres, Rosario; Usall, Josep; Fons, Estanislau; Teixidó, Neus

2017-08-01

The biocontrol agent Candida sake CPA-1 is effective against several diseases. Consequently, the optimisation of a dry formulation of C. sake to improve its shelf life and manipulability is essential for increasing its potential with respect to future commercial applications. The present study aimed to optimise the conditions for making a dry formulation of C. sake using a fluidised bed drying system and then to determine the shelf life of the optimised formulation and its efficacy against Penicillium expansum on apples. The optimal conditions for the drying process were found to be 40 °C for 45 min and the use of potato starch as the carrier significantly enhanced the viability. However, none of the protective compounds tested increased the viability of the dried cells. A temperature of 25 °C for 10 min in phosphate buffer was considered as the optimum condition to recover the dried formulations. The dried formulations should be stored at 4 °C and air-packaged; moreover, shelf life assays indicated good results after 12 months of storage. The formulated products maintained their biocontrol efficacy. A fluidised bed drying system is a suitable process for dehydrating C. sake cells; moreover, the C. sake formulation is easy to pack, store and transport, and is a cost-effective process. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

CFD Modeling of a CFB Riser Using Improved Inlet Boundary Conditions

NASA Astrophysics Data System (ADS)

Peng, B. T.; Zhang, C.; Zhu, J. X.; Qi, X. B.

2010-03-01

A computational fluid dynamics (CFD) model based on Eulerian-Eulerian approach coupled with granular kinetics theory was adopted to investigate the hydrodynamics and flow structures in a circulating fluidized bed (CFB) riser column. A new approach to specify the inlet boundary conditions was proposed in this study to simulate gas-solids flow in CFB risers more accurately. Simulation results were compared with the experimental data, and good agreement between the numerical results and experimental data was observed under different operating conditions, which indicates the effectiveness and accuracy of the CFD model with the proposed inlet boundary conditions. The results also illustrate a clear core annulus structure in the CFB riser under all operating conditions both experimentally and numerically.

Application of process tomography in gas-solid fluidised beds in different scales and structures

NASA Astrophysics Data System (ADS)

Wang, H. G.; Che, H. Q.; Ye, J. M.; Tu, Q. Y.; Wu, Z. P.; Yang, W. Q.; Ocone, R.

2018-04-01

Gas-solid fluidised beds are commonly used in particle-related processes, e.g. for coal combustion and gasification in the power industry, and the coating and granulation process in the pharmaceutical industry. Because the operation efficiency depends on the gas-solid flow characteristics, it is necessary to investigate the flow behaviour. This paper is about the application of process tomography, including electrical capacitance tomography (ECT) and microwave tomography (MWT), in multi-scale gas-solid fluidisation processes in the pharmaceutical and power industries. This is the first time that both ECT and MWT have been applied for this purpose in multi-scale and complex structure. To evaluate the sensor design and image reconstruction and to investigate the effects of sensor structure and dimension on the image quality, a normalised sensitivity coefficient is introduced. In the meantime, computational fluid dynamic (CFD) analysis based on a computational particle fluid dynamic (CPFD) model and a two-phase fluid model (TFM) is used. Part of the CPFD-TFM simulation results are compared and validated by experimental results from ECT and/or MWT. By both simulation and experiment, the complex flow hydrodynamic behaviour in different scales is analysed. Time-series capacitance data are analysed both in time and frequency domains to reveal the flow characteristics.

Effect of operating conditions on performance of silica gel-water air-fluidised desiccant cooler

NASA Astrophysics Data System (ADS)

Rogala, Zbigniew; Kolasiński, Piotr; Gnutek, Zbigniew

2017-11-01

Fluidised desiccant cooling is reported in the literature as an efficient way to provide cooling for air-conditioning purposes. The performance of this technology can be described by electric and thermal Coefficients of Performance (COP) and Specific Cooling Power (SCP). In this paper comprehensive theoretical study was carried out in order to assess the effect of operating conditions such as: superficial air velocity, desiccant particle diameter, bed switching time and desiccant filling height on the performance of fluidised desiccant cooler (FDC). It was concluded that FDC should be filled with as small as possible desiccant particles featuring diameters and should not be operated with shorter switching times than optimum. Moreover in order to efficiently run such systems superficial air velocities during adsorption and desorption should be similar. At last substantial effect of desiccant filling height on performance of FDC was presented.

Sludge incineration tests on circulating fluidised bed furnace.

PubMed

Lotito, V; Mininni, G; Di Pinto, A C; Spinosa, L

2001-01-01

Results of sludge incineration tests on a demonstrative fluidised bed furnace are reported and discussed. They show that particulate, heavy metals and acidic compounds in the emissions can be easily controlled both when sludge is spiked with chlorinated hydrocarbons up to a chlorine concentration in the feed of 5%, and when the afterburner is switched off. As for organic micropollutants, polynuclear aromatic hydrocarbons (PAH) were much lower than the Italian limits of 10 microg/m3 (no limits are at present considered in the European Directives). Dioxins (PCDDs) and furans (PCDFs) in some tests exceeded the limit of 0.1 ng/m3 (TE) but the concentrations in the fly ashes were much lower, thus evidencing a possible presence of contaminants in gas phase. PAHs and PCDD/PCDFs were not depending on the afterburning operation, the presence of organic chlorine in the feed sludge and the copper addition to sewage sludge.

Comparative simulation of a fluidised bed reformer using industrial process simulators

NASA Astrophysics Data System (ADS)

Bashiri, Hamed; Sotudeh-Gharebagh, Rahmat; Sarvar-Amini, Amin; Haghtalab, Ali; Mostoufi, Navid

2016-08-01

A simulation model is developed by commercial simulators in order to predict the performance of a fluidised bed reformer. As many physical and chemical phenomena take place in the reformer, two sub-models (hydrodynamic and reaction sub-models) are needed. The hydrodynamic sub-model is based on the dynamic two-phase model and the reaction sub-model is derived from the literature. In the overall model, the bed is divided into several sections. In each section, the flow of the gas is considered as plug flow through the bubble phase and perfectly mixed through the emulsion phase. Experimental data from the literature were used to validate the model. Close agreement was found between the model of both ASPEN Plus (ASPEN PLUS 2004 ©) and HYSYS (ASPEN HYSYS 2004 ©) and the experimental data using various sectioning of the reactor ranged from one to four. The experimental conversion lies between one and four sections as expected. The model proposed in this work can be used as a framework in developing the complicated models for non-ideal reactors inside of the process simulators.

Decomposing properties of phosphogypsum with iron addition under two-step cycle multi-atmosphere control in fluidised bed.

PubMed

Zheng, Dalong; Ma, Liping; Wang, Rongmou; Yang, Jie; Dai, Quxiu

2018-02-01

Phosphogypsum is a solid industry by-product generated when sulphuric acid is used to process phosphate ore into fertiliser. Phosphogypsum stacks without pretreatment are often piled on the land surface or dumped in the sea, causing significant environmental damage. This study examined the reaction characteristics of phosphogypsum, when decomposed in a multi-atmosphere fluidised bed. Phosphogypsum was first dried, sieved and mixed proportionally with lignite at the mass ratio of 10:1, it was then immersed in 0.8 [Formula: see text] with a solid-liquid ratio of 8:25. The study included a two-step cycle of multi-atmosphere control. First, a reducing atmosphere was provided to allow phosphogypsum decomposition through partial lignite combustion. After the reduction stage reaction was completed, the reducing atmosphere was changed into an air-support oxidising atmosphere at the constant temperature. Each atmosphere cycle had a conversion time of 30 min to ensure a sufficient reaction. The decomposing properties of phosphogypsum were obtained in different atmosphere cycles, at different reaction temperatures, different heating rates and different fluidised gas velocities, using experimental results combined with a theoretical analysis using FactSage 7.0 Reaction module. The study revealed that the optimum reaction condition was to circulate the atmosphere twice at a temperature of 1100 °C. The heating rate above 800 °C was 5 [Formula: see text], and the fluidised gas velocity was 0.40 [Formula: see text]. The procedure proposed in this article can serve as a phosphogypsum decomposition solution, and can support the future management of this by-product, resulting in more sustainable production.

Feasible experimental study on the utilization of a 300 MW CFB boiler desulfurizating bottom ash for construction applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lu, X.F.; Amano, R.S.

2006-12-15

CFB boiler ash cannot be used as a cement replacement in concrete due to its unacceptably high sulfur content. The disposal in landfills has been the most common means of handling ash in circulating fluidized bed boiler power plants. However for a 300 MW CFB boiler power plant, there will be 600,000 tons of ash discharged per year and will result in great volumes and disposal cost of ash byproduct. It was very necessary to solve the utilization of CFB ash and to decrease the disposal cost of CFB ash. The feasible experimental study results on the utilization of themore » bottom ashes of a 300 MW CFB boiler in Baima power plant in China were reported in this paper. The bottom ashes used for test came from the discharged bottom ashes in a 100 MW CFB boiler in which the anthracite and limestone designed for the 300 MW CFB project was burned. The results of this study showed that the bottom ash could be used for cementitious material, road concrete, and road base material. The masonry cements, road concrete with 30 MPa compressive strength and 4.0 MPa flexural strength, and the road base material used for base courses of the expressway, the main road and the minor lane were all prepared with milled CFB bottom ashes in the lab. The better methods of utilization of the bottom ashes were discussed in this paper.« less

Development of methane and nitrous oxide emission factors for the biomass fired circulating fluidized bed combustion power plant.

PubMed

Cho, Chang-Sang; Sa, Jae-Hwan; Lim, Ki-Kyo; Youk, Tae-Mi; Kim, Seung-Jin; Lee, Seul-Ki; Jeon, Eui-Chan

2012-01-01

This study makes use of this distinction to analyze the exhaust gas concentration and fuel of the circulating fluidized bed (CFB) boiler that mainly uses wood biomass, and to develop the emission factors of Methane (CH(4)), Nitrous oxide (N(2)O). The fuels used as energy sources in the subject working sites are Wood Chip Fuel (WCF), RDF and Refused Plastic Fuel (RPF) of which heating values are 11.9 TJ/Gg, 17.1 TJ/Gg, and 31.2 TJ/Gg, respectively. The average concentrations of CH(4) and N(2)O were measured to be 2.78 ppm and 7.68 ppm, respectively. The analyzed values and data collected from the field survey were used to calculate the emission factor of CH(4) and N(2)O exhausted from the CFB boiler. As a result, the emission factors of CH(4) and N(2)O are 1.4 kg/TJ (0.9-1.9 kg/TJ) and 4.0 kg/TJ (2.9-5.3 kg/TJ) within a 95% confidence interval. Biomass combined with the combustion technology for the CFB boiler proved to be more effective in reducing the N(2)O emission, compared to the emission factor of the CFB boiler using fossil fuel.

Carbon attrition during the circulating fluidized bed combustion of a packaging-derived fuel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mastellone, M.L.; Arena, U.

1999-05-01

Cylindrical pellets of a market-available packaging-derived fuel, obtained from a mono-material collection of polyethylene terephthalate (PET) bottles, were batchwise fed to a laboratory scale circulating fluidized bed (CFB) combustor. The apparatus, whose riser was 41 mm ID and 4 m high, was operated under both inert and oxidizing conditions to establish the relative importance of purely mechanical attrition and combustion-assisted attrition in generating carbon fines. Silica sand particles of two size distributions were used as inert materials. For each run, carbon load and carbon particle size distribution in the riser and rates of attrited carbon fines escaping the combustor weremore » determined as a function of time. A parallel investigation was carried out with a bubbling fluidized bed (BFB) combustor to point out peculiarities of attrition in CFB combustors. After devolatilization, PET pellets generated fragile aggregates of char and sand, which easily crumbled, leading to single particles, partially covered by a carbon-rich layer. The injected fixed carbon was therefore present in the bed in three phases: an A-phase, made of aggregates of sand and char, an S-phase, made of individual carbon-covered sand particles and an F-phase, made of carbon fines, abraded by the surfaces of the A- and S-phases. The effects of the size of inert material on the different forms under which fixed carbon was present in the bed and on the rate of escape of attrited carbon fines from the combustor were investigated. Features of carbon attrition in CFB and BFB combustors are discussed.« less

Decreased PCDD/F formation when co-firing a waste fuel and biomass in a CFB boiler by addition of sulphates or municipal sewage sludge

DOE Office of Scientific and Technical Information (OSTI.GOV)

Åmand, Lars-Erik; Kassman, Håkan, E-mail: hakan.kassman@vattenfall.com

2013-08-15

Highlights: • Two strategies to reduce PCDD/F formation when co-firing solid recovered fuel (SRF) and biomass. • They were co-combustion with municipal sewage sludge (MSS) and addition of ammonium sulphate. • PCDD/Fs were significantly reduced for a biomass rich in chlorine when adding ammonium sulphate. • MSS had a suppressing effect on PCDD/F formation during co-combustion with SRF. • A link is presented between gaseous alkali chlorides, chlorine in deposits and PCDD/F formation. - Abstract: Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are formed during waste incineration and in waste-to-energy boilers. Incomplete combustion, too short residence times at low combustionmore » temperatures (<700 °C), incineration of electronic waste and plastic waste containing chlorine are all factors influencing the formation of PCDD/Fs in boilers. The impact of chlorine and catalysing metals (such as copper and iron) in the fuel on PCDD/F formation was studied in a 12 MW{sub th} circulating fluidised bed (CFB) boiler. The PCDD/F concentrations in the raw gas after the convection pass of the boiler and in the fly ashes were compared. The fuel types were a so-called clean biomass with low content of chlorine, biomass with enhanced content of chlorine from supply of PVC, and solid recovered fuel (SRF) which is a waste fuel containing higher concentrations of both chlorine, and catalysing metals. The PCDD/F formation increased for the biomass with enhanced chlorine content and it was significantly reduced in the raw gas as well as in the fly ashes by injection of ammonium sulphate. A link, the alkali chloride track, is demonstrated between the level of alkali chlorides in the gas phase, the chlorine content in the deposits in the convection pass and finally the PCDD/F formation. The formation of PCDD/Fs was also significantly reduced during co-combustion of SRF with municipal sewage sludge (MSS) compared to when SRF was fired without MSS as additional fuel.« less

CFD Modelling Applied to the Co-Combustion of Paper Sludge and Coal in a 130 t/h CFB Boiler

NASA Astrophysics Data System (ADS)

Yu, Z. S.; Ma, X. Q.; Lai, Z. Y.; Xiao, H. M.

Three-dimensional mathematical model has been developed as a tool for co-combustion of paper sludge and coal in a 130 tJh Circulating Fluidized Bed (CFB) boiler. Mathematical methods had been used based on a commercial software FLUENT for combustion. The predicted results of CFB furnace show that the co-combustion of paper sludge/coal is initially intensively at the bottom of bed; the temperature reaches its maximum in the dense-phase zone, around l400K. It indicates that paper sludge spout into furnace from the recycle inlet can increase the furnace maximum temperature (l396.3K), area-weighted average temperature (l109.6K) and the furnace gas outlet area-weighted average temperature(996.8K).The mathematical modeling also predicts that 15 mass% paper sludge co-combustion is the highest temperature at the flue gas outlet, it is 1000.8K. Moreover, it is proved that mathematical models can serve as a tool for detailed analysis of co-combustion of paper sludge and coal processes in a circulating fluidized bed furnace when in view of its convenience. The results gained from numerical simulation show that paper sludge enter into furnace from the recycle inlet excelled than mixing with coal and at the underside of phase interface.

Mercury Emission Measurement at a CFB Plant

DOE Office of Scientific and Technical Information (OSTI.GOV)

John Pavlish; Jeffrey Thompson; Lucinda Hamre

2009-02-28

In response to pending regulation to control mercury emissions in the United States and Canada, several projects have been conducted to perform accurate mass balances at pulverized coal (pc)-fired utilities. Part of the mercury mass balance always includes total gaseous mercury as well as a determination of the speciation of the mercury emissions and a concentration bound to the particulate matter. This information then becomes useful in applying mercury control strategies, since the elemental mercury has traditionally been difficult to control by most technologies. In this instance, oxidation technologies have proven most beneficial for increased capture. Despite many years ofmore » mercury measurement and control projects at pc-fired units, far less work has been done on circulating fluidized-bed (CFB) units, which are able to combust a variety of feedstocks, including cofiring coal with biomass. Indeed, these units have proven to be more problematic because it is very difficult to obtain a reliable mercury mass balance. These units tend to have very different temperature profiles than pc-fired utility boilers. The flexibility of CFB units also tends to be an issue when a mercury balance is determined, since the mercury inputs to the system come from the bed material and a variety of fuels, which can have quite variable chemistry, especially for mercury. In addition, as an integral part of the CFB operation, the system employs a feedback loop to circulate the bed material through the combustor and the solids collection system (the primary cyclone), thereby subjecting particulate-bound metals to higher temperatures again. Despite these issues, CFB boilers generally emit very little mercury and show good native capture. The Energy & Environmental Research Center is carrying out this project for Metso Power in order to characterize the fate of mercury across the unit at Rosebud Plant, an industrial user of CFB technology from Metso. Appropriate solids were collected, and flue gas samples were obtained using the Ontario Hydro method, mercury continuous emission monitors, and sorbent trap methods. In addition, chlorine and fluorine were determined for solids and in the flue gas stream. Results of this project have indicated a very good mercury mass balance for Rosebud Plant, indicating 105 {+-} 19%, which is well within acceptable limits. The mercury flow through the system was shown to be primarily in with the coal and out with the flue gas, which falls outside of the norm for CFB boilers.« less

Commercialization Development of Oxygen Fired CFB for Greenhouse Gas Control

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nsakala ya Nsakala; Gregory N. Liljedahl; David G. Turek

2007-03-31

Given that fossil fuel fired power plants are among the largest and most concentrated producers of CO{sub 2} emissions, recovery and sequestration of CO{sub 2} from the flue gas of such plants has been identified as one of the primary means for reducing anthropogenic (i.e., man-made) CO{sub 2} emissions. In 2001, ALSTOM Power Inc. (ALSTOM) began a two-phase program to investigate the feasibility of various carbon capture technologies. This program was sponsored under a Cooperative Agreement from the US Department of Energy's National Energy Technology Laboratory (DOE). The first phase entailed a comprehensive study evaluating the technical feasibility and economicsmore » of alternate CO{sub 2} capture technologies applied to Greenfield US coal-fired electric generation power plants. Thirteen cases, representing various levels of technology development, were evaluated. Seven cases represented coal combustion in CFB type equipment. Four cases represented Integrated Gasification Combined Cycle (IGCC) systems. Two cases represented advanced Chemical Looping Combined Cycle systems. Marion, et al. reported the details of this work in 2003. One of the thirteen cases studied utilized an oxygen-fired circulating fluidized bed (CFB) boiler. In this concept, the fuel is fired with a mixture of oxygen and recirculated flue gas (mainly CO{sub 2}). This combustion process yields a flue gas containing over 80 percent (by volume) CO{sub 2}. This flue gas can be processed relatively easily to enrich the CO{sub 2} content to over 96 percent for use in enhanced oil or gas recovery (EOR or EGR) or simply dried for sequestration. The Phase I study identified the O{sub 2}-fired CFB as having a near term development potential, because it uses conventional commercial CFB technology and commercially available CO{sub 2} capture enabling technologies such as cryogenic air separation and simple rectification or distillation gas processing systems. In the long term, air separation technology advancements offer significant reductions in power requirements, which would improve plant efficiency and economics for the oxygen-fired technology. The second phase consisted of pilot-scale testing followed by a refined performance and economic evaluation of the O{sub 2} fired CFB concept. As a part of this workscope, ALSTOM modified its 3 MW{sub th} (9.9 MMBtu/hr) Multiuse Test Facility (MTF) pilot plant to operate with O{sub 2}/CO{sub 2} mixtures of up to 70 percent O{sub 2} by volume. Tests were conducted with coal and petroleum coke. The test objectives were to determine the impacts of oxygen firing on heat transfer, bed dynamics, potential agglomeration, and gaseous and particulate emissions. The test data results were used to refine the design, performance, costs, and economic models developed in Phase-I for the O{sub 2}-fired CFB with CO{sub 2} capture. Nsakala, Liljedahl, and Turek reported results from this study in 2004. ALSTOM identified several items needing further investigation in preparation for large scale demonstration of the oxygen-fired CFB concept, namely: (1) Operation and performance of the moving bed heat exchanger (MBHE) to avoid recarbonation and also for cost savings compared to the standard bubbling fluid bed heat exchanger (FBHE); (2) Performance of the back-end flash dryer absorber (FDA) for sulfur capture under high CO{sub 2}/high moisture flue gas environment using calcined limestone in the fly ash and using fresh commercial lime directly in the FDA; (3) Determination of the effect of recarbonation on fouling in the convective pass; (4) Assessment of the impact of oxygen firing on the mercury, other trace elements, and volatile organic compound (VOC) emissions; and (5) Develop a proposal-level oxygen-fired retrofit design for a relatively small existing CFB steam power plant in preparation for a large-scale demonstration of the O{sub 2} fired CFB concept. Hence, ALSTOM responded to a DOE Solicitation to address all these issues with further O{sub 2} fired MTF pilot testing and a subsequent retrofit design study of oxygen firing and CO{sub 2} capture on an existing air-fired CFB plant. ALSTOM received a contract award from the DOE to conduct a project entitled 'Commercialization Development of Oxygen Fired CFB for Greenhouse Gas Control', under Cooperative Agreement DE-FC26-04NT42205 that is the subject of this topical report.« less

Bio-oil production via fast pyrolysis of biomass residues from cassava plants in a fluidised-bed reactor.

PubMed

Pattiya, Adisak

2011-01-01

Biomass residues from cassava plants, namely cassava stalk and cassava rhizome, were pyrolysed in a fluidised-bed reactor for production of bio-oil. The aims of this work were to investigate the yields and properties of pyrolysis products produced from both feedstocks as well as to identify the optimum pyrolysis temperature for obtaining the highest organic bio-oil yields. Results showed that the maximum yields of the liquid bio-oils derived from the stalk and rhizome were 62 wt.% and 65 wt.% on dry basis, respectively. The pyrolysis temperatures that gave highest bio-oil yields for both feedstocks were in the range of 475-510 °C. According to the analysis of the bio-oils properties, the bio-oil derived from cassava rhizome showed better quality than that derived from cassava stalk as the former had lower oxygen content, higher heating value and better storage stability. Copyright © 2010 Elsevier Ltd. All rights reserved.

Simultaneous organic nitrogen and sulfate removal in an anaerobic GAC fluidised bed reactor.

PubMed

Fdz-Polanco, F; Fdz-Polanco, M; Fernandez, N; Urueña, M A; García, P A; Villaverde, S

2001-01-01

A granular activated carbon (GAC) anaerobic fluidised bed reactor treating vinasse from an ethanol distillery of sugar beet molasses was operated for 250 days under three different organic loading rates. The reactor showed good performance in terms of organic matter removal and methane production but an anomalous behaviour in terms of unusual high concentrations of molecular nitrogen and low concentration of hydrogen sulphide in the biogas. The analysis of the different nitrogenous and sulphur compounds and the mass balances of these species in the liquid and gas phases clearly indicated an uncommon evolution of nitrogen and sulphur in the reactor. Up to 55% of the TKN and up to 80% of the sulphur disappear in the liquid phase. This is the opposite to any previously reported results in the bibliography. The new postulated anaerobic process of ammonia and sulphate removal seems to follow the mechanism: SO4 = +2 NH4+-->S + N2 + 4H2O (delta G degree = -47.8 kJ/mol).

Development of Methane and Nitrous Oxide Emission Factors for the Biomass Fired Circulating Fluidized Bed Combustion Power Plant

PubMed Central

Cho, Chang-Sang; Sa, Jae-Hwan; Lim, Ki-Kyo; Youk, Tae-Mi; Kim, Seung-Jin; Lee, Seul-Ki; Jeon, Eui-Chan

2012-01-01

This study makes use of this distinction to analyze the exhaust gas concentration and fuel of the circulating fluidized bed (CFB) boiler that mainly uses wood biomass, and to develop the emission factors of Methane (CH4), Nitrous oxide (N2O). The fuels used as energy sources in the subject working sites are Wood Chip Fuel (WCF), RDF and Refused Plastic Fuel (RPF) of which heating values are 11.9 TJ/Gg, 17.1 TJ/Gg, and 31.2 TJ/Gg, respectively. The average concentrations of CH4 and N2O were measured to be 2.78 ppm and 7.68 ppm, respectively. The analyzed values and data collected from the field survey were used to calculate the emission factor of CH4 and N2O exhausted from the CFB boiler. As a result, the emission factors of CH4 and N2O are 1.4 kg/TJ (0.9–1.9 kg/TJ) and 4.0 kg/TJ (2.9–5.3 kg/TJ) within a 95% confidence interval. Biomass combined with the combustion technology for the CFB boiler proved to be more effective in reducing the N2O emission, compared to the emission factor of the CFB boiler using fossil fuel. PMID:23365540

Proven clean coal technology at work: The Provence 250 MW CFB boiler

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lucat, P.; Jacquet, L.; Roulet, V.

The successful start-up, in the last months of 1995, of the 250 MW Provence/Gardanne unit represents a significant milestone in the development of atmospheric Circulating Fluidized Bed (CFB) boilers for power stations. This high performance unit (over 700 tonnes/hour of steam at 169 bar, 567 C, with reheat at 566 C) has been in operation since April 1996. It is the first CFB boiler in the world to reach such a capacity. CFB boilers, with their excellent SO{sub 2} and NOx emission control capability, are today recognized as a very attractive Clean Coal Technology, particularly because of their simplicity. Themore » Provence/Gardanne project is part of a French development program for large CFB boilers which has been elaborated in the perspective of domestic applications (mainly future semi-base load units) and of the overseas market. It responds to the converging interests of Electricite de France (EDF), Charbonnages de France (CdF)and GEC ALSTHOM Stein Industrie. Besides comprehensive R and D-type investigations aiming at an in-depth understanding of the CFB process and preparing for future scale-up and development, this program has already been marked by two outstanding commercial repowering projects: a 125 MW unit, in operation since 1990 at the Emile Huchet Power Station, and the 250 MW Provence unit. These boilers have been designed and supplied by GEC ALSTHOM Stein Industrie in the framework of their long standing cooperation with Lurgi, a pioneer of the CFB process. The main components are: (1) Furnace; (2) Cyclone; (3) Back-pass; (4) Ash cooler; (5) External Heat Exchanger. However, a brief discussion of some key design options affecting bed performance is necessary to better understand this technology. The paper describes the design of the system, the retrofitting project at Emile Huchet/Carling, and then gives background information on the Provence/Gardanne retrofit, describing SO{sub 2} emissions, the 250 MW boiler, and results from the performance tests. The recent performance tests as well as the operating experience already accumulated demonstrates that the Provence Clean Energy Project participants have successfully overcome the scale-up challenge represented by the construction of the first 250 MW CFB boiler in the world. This simple and attractive clean coal technology is now ready for many commercial applications in power stations. Units up to 300-400 MW can be built right now, using the lessons learned at Provence. Development of 600 MW-class CFB boilers, subcritical or supercritical, appears within reach in the near future.« less

Development of Flexi-Burn™ CFB Power Plant to Meet the Challenge of Climate Change

NASA Astrophysics Data System (ADS)

Hackt, Horst; Fant, Zhen; Seltzert, Andrew; Hotta, Arto; Erikssoni, Timo; Sippu, Ossi

Carbon-dioxide capture and storage (CCS) offers the potential for major reductions in carbon- dioxide emissions of fossil fuel-based power generation in the fairly short term, and oxyfuel combustion is one of the identified CCS technology options. Foster Wheeler (FW) is working on reduction of carbon-dioxide with its integrated Flexi-Burn™ CFB technology. The proven high efficiency circulating fluidized-bed (CFB) technology, when coupled with air separation units and carbon purification units, offers a solution for carbon dioxide reduction both in re-powering and in greenfield power plants. CFB technology has the advantages over pulverized coal technology of a more uniform furnace heat flux, increased fuel flexibility and offers the opportunity to further reduce carbon dioxide emissions by co-firing coal with bio-fuels. Development and design of an integrated Flexi-Bum™ CFB steam generator and balance of plant system was conducted for both air mode and oxyfuel mode. Through proper configuration and design, the same steam generator can be switched from air mode to oxyfuel mode without the need for unit shutdown for modifications. The Flexi-Burn™ CFB system incorporates features to maximize plant efficiency and power output when operating in the oxy-firing mode through firing more fuel in the same boiler.

Study of CFB Simulation Model with Coincidence at Multi-Working Condition

NASA Astrophysics Data System (ADS)

Wang, Z.; He, F.; Yang, Z. W.; Li, Z.; Ni, W. D.

A circulating fluidized bed (CFB) two-stage simulation model was developed. To realize the model results coincident with the design value or real operation value at specified multi-working conditions and with capability of real-time calculation, only the main key processes were taken into account and the dominant factors were further abstracted out of these key processes. The simulation results showed a sound accordance at multi-working conditions, and confirmed the advantage of the two-stage model over the original single-stage simulation model. The combustion-support effect of secondary air was investigated using the two-stage model. This model provides a solid platform for investigating the pant-leg structured CFB furnace, which is now under design for a supercritical power plant.

1300°F 800 MWe USC CFB Boiler Design Study

NASA Astrophysics Data System (ADS)

Robertson, Archie; Goidich, Steve; Fan, Zhen

Concern about air emissions and the effect on global warming is one of the key factors for developing and implementing new advanced energy production solutions today. One state-of-the-art solution is circulating fluidized bed (CFB) combustion technology combined with a high efficiency once-through steam cycle. Due to this extremely high efficiency, the proven CFB technology offers a good solution for CO2 reduction. Its excellent fuel flexibility further reduces CO2 emissions by co-firing coal with biomass. Development work is under way to offer CFB technology up to 800MWe capacities with ultra-supercritical (USC) steam parameters. In 2009 a 460MWe once-through supercritical (OTSC) CFB boiler designed and constructed by Foster Wheeler will start up. However, scaling up the technology further to 600-800MWe with net efficiency of 45-50% is needed to meet the future requirements of utility operators. To support the move to these larger sizes, an 800MWe CFB boiler conceptual design study was conducted and is reported on herein. The use of USC conditions (˜11 00°F steam) was studied and then the changes, that would enable the unit to generate 1300°F steam, were identified. The study has shown that by using INTREX™ heat exchangers in a unique internal-external solids circulation arrangement, Foster Wheeler's CFB boiler configuration can easily accommodate 1300°F steam and will not require a major increase in heat transfer surface areas.

Study of Gas Solid Flow Characteristics in Cyclone Inlet Ducts of A300Mwe CFB Boiler

NASA Astrophysics Data System (ADS)

Tang, J. Y.; Lu, X. F.; Lai, J.; Liu, H. Z.

Gas solid flow characteristics in cyclone's inlet duct of a 300MW CFB boiler were studied in a cold circulating fluidized bed (CFB) experimental setup according to a 410t/h CFB boiler with a scale of 10∶1. Tracer particles were adopted in the experiment and their motion trajectories in the two kinds of cyclone's inlet ducts were photographed by a high-speed camera. By analyzing the motion trajectories of tracer particles, acceleration performance of particle phases in the two inlet ducts was obtained. Results indicate that the acceleration performance of particles in the long inlet duct is better than that in the short inlet duct, but the pressure drop of the long inlet duct is higher. Meanwhile, under the same operating conditions, both the separation efficiency and the pressure drop of the cyclone are higher when the cyclone is connected with the long inlet duct. Figs 11, Tabs 4 and refs 10.

Experiment Investigation of the Influencing Factors on Bed Agglomeration During Fluidized-Bed Gasification of Biomass Fuels

NASA Astrophysics Data System (ADS)

Chen, Y. Q.; Chen, H. P.; Yang, H. P.; Wang, X. H.; Zhang, S. H.

With the depleting of fossil fuel and environmental polluting increasing, the utilization of biomass resources caught increasing concern. Biomass gasification in fluidized bed, as one promising technology, developed quickly. However, serious agglomeration was displayed as biomass ash reacted with bed material (silica sand) at higher temperature. It hindered the wide utilization of CFB gasifier. The objective ofthis work is to investigate the agglomeration behavior between biomass ash and silica sand, and catch the inherent mechanism. Firstly, the influence of ash compounds on the agglomeration behavior was analyzed with biomass ash and synthesis ash compounds addition in fixed bed as ash sample mixed with bed material evenly before every trial. The reaction temperature was set 850°C that is the operated temperature for many fluidized bed gasificated biomass fuels. Then the influence of reaction time was analyzed. The characteristics of the agglomerated silica sand particles were analyzed by the XRD. Finally, it was simulated with HSC computer mode based on thermodynamic equilibrium. It was observed that when the ratio of the biomass ash to the silica sand was above 0.2, the agglomeration was observed. With the increase of the reaction time, more silica sand particles agglomerated with the biomass ash. There are two kinds of silicate eutecticum investigated by the XRD. It is of great significance for the running ofCFB biomass gasifier and the development ofbiomass utilization technology.

Thermal treatment of electronic waste in a fluidised bed and chemical digestion of solid products.

PubMed

Woynarowska, Amelia; Żukowski, Witold; Żelazny, Sylwester

2016-07-01

The article presents the results of e-waste thermal treatment in a fluidised bed reactor and solid products digestion under acidic conditions. During the processes, measurements of carbon monoxide, carbon dioxide, volatile organic compounds, nitrogen oxides, sulphur dioxide, hydrogen chloride, hydrogen bromide, hydrogen cyanide, ammonia, phenol, aliphatic and aromatic hydrocarbons, hydrogen fluoride and phosgene were carried out. Several digestion tests of the solid residue in sulphuric acid (VI) at 25 °C-65 °C, for 55 min-24 h were conducted. In each case, the dilution method was used, i.e. preliminary digestion in concentrated sulphuric acid (VI) (95%) for 40 min, and then dilution to expected concentrations (30%-50%). Most preferred results were obtained using sulphuric acid (VI) with a target concentration of 40% at 65 °C, where the leaching degrees were 76.56% for copper, 71.67% for iron, 91.89% for zinc and 97.40% for tin. The time necessary to effectively carry out the digestion process was 220 min. © The Author(s) 2016.

Imaging wet granules with different flow patterns by electrical capacitance tomography and microwave tomography

NASA Astrophysics Data System (ADS)

Wang, H. G.; Zhang, J. L.; Ramli, M. F.; Mao, M. X.; Ye, J. M.; Yang, W. Q.; Wu, Z. P.

2016-11-01

The moisture content of granules in fluidised bed drying, granulation and coating processes can typically be between 1%~25%, resulting in the change of permittivity and conductivity during the processes. Electrical capacitance tomography (ECT) has been used for this purpose, but has a limit because too much water can cause a problem in capacitance measurement. Considering that microwave tomography (MWT) has a wide range of frequency (1~2.5 GHz) and can be used to measure materials with high permittivity and conductivity, the objective of this research is to combine ECT and MWT together to investigate the solids concentration with different moisture content and different flow patterns. The measurement results show that both ECT and MWT are functions of moisture content as well as flow patterns, and their measurements are complementary to each other. This is the first time that these two tomography modalities have been combined together and applied to image the complex solids distribution. The obtained information may be used for the process control of fluidised bed drying, granulation and coating to improve operation efficiency.

The enrichment of natural radionuclides in oil shale-fired power plants in Estonia--the impact of new circulating fluidized bed technology.

PubMed

Vaasma, Taavi; Kiisk, Madis; Meriste, Tõnis; Tkaczyk, Alan Henry

2014-03-01

Burning oil shale to produce electricity has a dominant position in Estonia's energy sector. Around 90% of the overall electric energy production originates from the Narva Power Plants. The technology in use has been significantly renovated - two older types of pulverized fuel burning (PF) energy production units were replaced with new circulating fluidized bed (CFB) technology. Additional filter systems have been added to PF boilers to reduce emissions. Oil shale contains various amounts of natural radionuclides. These radionuclides concentrate and become enriched in different boiler ash fractions. More volatile isotopes will be partially emitted to the atmosphere via flue gases and fly ash. To our knowledge, there has been no previous study for CFB boiler systems on natural radionuclide enrichment and their atmospheric emissions. Ash samples were collected from Eesti Power Plant's CFB boiler. These samples were processed and analyzed with gamma spectrometry. Activity concentrations (Bq/kg) and enrichment factors were calculated for the (238)U ((238)U, (226)Ra, (210)Pb) and (232)Th ((232)Th, (228)Ra) family radionuclides and for (40)K in different CFB boiler ash fractions. Results from the CFB boiler ash sample analysis showed an increase in the activity concentrations and enrichment factors (up to 4.5) from the furnace toward the electrostatic precipitator block. The volatile radionuclide ((210)Pb and (40)K) activity concentrations in CFB boilers were evenly distributed in finer ash fractions. Activity balance calculations showed discrepancies between input (via oil shale) and output (via ash fractions) activities for some radionuclides ((238)U, (226)Ra, (210)Pb). This refers to a situation where the missing part of the activity (around 20% for these radionuclides) is emitted to the atmosphere. Also different behavior patterns were detected for the two Ra isotopes, (226)Ra and (228)Ra. A part of (226)Ra input activity, unlike (228)Ra, was undetectable in the solid ash fractions of the boiler. Most probably it is released to the surrounding environment. Copyright © 2014 Elsevier Ltd. All rights reserved.

Hydrolysis, acidification and methanogenesis during low-temperature anaerobic digestion of dilute dairy wastewater in an inverted fluidised bioreactor.

PubMed

Bialek, Katarzyna; Cysneiros, Denise; O'Flaherty, Vincent

2014-10-01

The application of low-temperature (10 °C) anaerobic digestion (LtAD) for the treatment of complex dairy-based wastewater in an inverted fluidised bed (IFB) reactor was investigated. Inadequate mixing intensity provoked poor hydrolysis of the substrate (mostly protein), which resulted in low chemical oxygen demand (COD) removal efficiency throughout the trial, averaging ~69 % at the best operational period. Overgrowth of the attached biomass to the support particles (Extendospheres) induced bed stratification by provoking agglutination of the particles and supporting their washout by sedimentation, which contributed to unstable bioprocess performance at the organic loading rates (OLRs) between 0.5 and 5 kg COD m(-3) day(-1). An applied OLR above 2 kg COD m(-3) day(-1) additionally promoted acidification and strongly influenced the microbial composition and dynamics. Hydrogenotrophic methanogens appeared to be the mostly affected group by the Extendospheres particle washout as a decrease in their abundance was observed by quantitative PCR analysis towards the end of the trial, although the specific methanogenic activity and maximum substrate utilisation rate on H2/CO2 indicated high metabolic activity and preference towards hydrogenotrophic methanogenesis of the reactor biomass at this stage. The bacterial community in the bioreactor monitored via denaturing gradient gel electrophoresis (DGGE) also suggested an influence of OLR stress on bacterial community structure and population dynamics. The data presented in this work can provide useful information in future optimisation of fluidised reactors intended for digestion of complex industrial wastewaters during LtAD.

Development and Validation of a 3-Dimensional CFB Furnace Model

NASA Astrophysics Data System (ADS)

Vepsäläinen, Arl; Myöhänen, Karl; Hyppäneni, Timo; Leino, Timo; Tourunen, Antti

At Foster Wheeler, a three-dimensional CFB furnace model is essential part of knowledge development of CFB furnace process regarding solid mixing, combustion, emission formation and heat transfer. Results of laboratory and pilot scale phenomenon research are utilized in development of sub-models. Analyses of field-test results in industrial-scale CFB boilers including furnace profile measurements are simultaneously carried out with development of 3-dimensional process modeling, which provides a chain of knowledge that is utilized as feedback for phenomenon research. Knowledge gathered by model validation studies and up-to-date parameter databases are utilized in performance prediction and design development of CFB boiler furnaces. This paper reports recent development steps related to modeling of combustion and formation of char and volatiles of various fuel types in CFB conditions. Also a new model for predicting the formation of nitrogen oxides is presented. Validation of mixing and combustion parameters for solids and gases are based on test balances at several large-scale CFB boilers combusting coal, peat and bio-fuels. Field-tests including lateral and vertical furnace profile measurements and characterization of solid materials provides a window for characterization of fuel specific mixing and combustion behavior in CFB furnace at different loads and operation conditions. Measured horizontal gas profiles are projection of balance between fuel mixing and reactions at lower part of furnace and are used together with both lateral temperature profiles at bed and upper parts of furnace for determination of solid mixing and combustion model parameters. Modeling of char and volatile based formation of NO profiles is followed by analysis of oxidizing and reducing regions formed due lower furnace design and mixing characteristics of fuel and combustion airs effecting to formation ofNO furnace profile by reduction and volatile-nitrogen reactions. This paper presents CFB process analysis focused on combustion and NO profiles in pilot and industrial scale bituminous coal combustion.

CFD Modelling of Particle Mixtures in a 2D CFB

NASA Astrophysics Data System (ADS)

Seppälä, M.; Kallio, S.

The capability of Fluent 6.2.16 to simulate particle mixtures in a laboratory scale 2D circulating fluidized bed (CFB) unit has been tested. In the simulations, the solids were described as one or two particle phases. The loading ratio of small to large particles, particle diameters and the gas inflow velocity were varied. The 40 cm wide and 3 m high 2D CFB was modeled using a grid with 31080 cells. The outflow of particles at the top of the CFB was monitored and emanated particles were fed back to the riser through a return duct. The paper presents the segregation patterns of the particle phases obtained from the simulations. When the fraction of large particles was 50% or larger, large particles segregated, as expected, to the wall regions and to the bottom part of the riser. However, when the fraction of large particles was 10%, an excess of large particles was found in the upper half of the riser. The explanation for this unexpected phenomenon was found in the distribution of the large particles between the slow clusters and the faster moving lean suspension.

Design and operation experience of 230 MWe CFB boilers at Turow power plant in Poland

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nowak, W.; Bis, Z.; Laskawiec, J.

The Power Station Turow is located in Bogatynia, Poland, and has operated 10 pulverized coal units each of 200 MW. The plant provided 2000 MW at the lowest cost per kWh in Poland. The Turow units have approached and in some cases already gone beyond their 25--30 year's design life. To meet Poland's new environmental standards, which are now compatible with the EU, Turow decided to replace and upgrade six units (No. 1 to 6) from 200 MW to 230 MW units and remove one unit No. 7. Units No. 8, 9 and 10 were equipped with dry sorbent desulfurizationmore » technology. Units No. 1 and 2 have been replaced with new clean coal circulating fluidized bed technology. The Power Station Turow with six CFB units is to be the largest in the world power station based on fluidized bed technology.« less

Numerical Simulation on Hydrodynamics and Combustion in a Circulating Fluidized Bed under O2/CO2 and Air Atmospheres

NASA Astrophysics Data System (ADS)

Zhou, W.; Zhao, C. S.; Duan, L. B.; Qu, C. R.; Lu, J. Y.; Chen, X. P.

Oxy-fuel circulating fluidized bed (CFB) combustion technology is in the stage of initial development for carbon capture and storage (CCS). Numerical simulation is helpful to better understanding the combustion process and will be significant for CFB scale-up. In this paper, a computational fluid dynamics (CFD) model was employed to simulate the hydrodynamics of gas-solid flow in a CFB riser based on the Eulerian-Granular multiphase model. The cold model predicted the main features of the complex gas-solid flow, including the cluster formation of the solid phase along the walls, the flow structure of up-flow in the core and downward flow in the annular region. Furthermore, coal devolatilization, char combustion and heat transfer were considered by coupling semi-empirical sub-models with CFD model to establish a comprehensive model. The gas compositions and temperature profiles were predicted and the outflow gas fractions are validated with the experimental data in air combustion. With the experimentally validated model being applied, the concentration and temperature distributions in O2/CO2 combustion were predicted. The model is useful for the further development of a comprehensive model including more sub-models, such as pollutant emissions, and better understanding the combustion process in furnace.

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

Circulating fluidized-bed (CFB) boilers have ben used for years in Scandinavia to burn refuse-derived fuel (RDF). Now, Foster Wheeler Power Systems, Inc., (Clinton, N.J.) is bringing the technology to the US. Touted as the world`s largest waste-to-energy plant to use CFB technology, the Robbins (III.) Resource Recovery Facility will have the capacity to process 1,600 tons/d of municipal solid waste (MSW) when it begins operation in early 1997. The facility will have two materials-separation and RDF-processing trains, each with dual trommel screens, magnetic and eddy current separators, and shredders. About 25% of the incoming MSW will be sorted and removedmore » for recycling, while 75% of it will be turned into fuel, with a heat value of roughly 6,170 btu/lb. Once burned in the twin CFB boilers the resulting steam will be routed through a single turbine generator to produce 50,000 mW of electric power.« less

Attrition of coal ash particles in a fluidized-bed reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tomeczek, J.; Mocek, P.

2007-05-15

Experimental data of ash-particles attrition in a fluidized bed is presented, and also the results of modeling. Five sizes of ash particles (1.02-1.25; 1.25-1.6; 1.6-2.0; 2.0-5.0; 5.0-10.0 mm) produced in an industrial CFB boiler were examined. A new model of mechanical attrition has been proposed which incorporates new parameters: the shape factor of particles and the ratio of the bed height to bed diameter, strongly influencing the rate of bed mass loss. The model describes very well experimental data for coal-ash particles attrition. The attrition-rate coefficient for ash particles was evaluated.

ECKG Kladno project: First IPP in the Czech Republic

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rode, J.R.; Tichy, O.J.

1999-07-01

The Energy Center Kladno project is the first independent power producer (IPP) project to be financed in the Czech Republic, one of Europe's most rapidly evolving markets. The total financing is $401 million and is structured in three currencies; Czech crowns, German marks, and US dollars. This paper will focus on: Enhanced technology to meet energy demands; Execution to meet the ambitious; and Overall project status. The coal and gas fired plant will produce a total of 343 MW to provide electricity and heat to the town of Kladno, west of Prague. The new plant will be located within themore » existing ECK facility and the project encompasses demolition, upgrading, and rebuilding. The base load will be from two coal-fired 135 MW circulating fluidized bed (CFB) boilers and peaking capacity from the gas-fired combustion (66 MW) turbine. The CFB's will fire a range of low sulfur brown coal supplied from the local mining company Ceskomoravske Doly (CMD). The new CFB's were designed to meet the overall steam demands specified by ECKG. The CFB's design features include in-furnace heat transfer surface and a split backpass that utilizes a biasing damper to allow for control of both the superheat and reheat steam temperatures. The various CFB auxiliary systems will be discussed in the paper as well as the flue gas particulate collection equipment.« less

Evaluation of Encapsulated Liver Cell Spheroids in a Fluidised-Bed Bioartificial Liver for Treatment of Ischaemic Acute Liver Failure in Pigs in a Translational Setting

PubMed Central

Selden, Clare; Spearman, Catherine Wendy; Kahn, Delawir; Miller, Malcolm; Figaji, Anthony; Erro, Eloy; Bundy, James; Massie, Isobel; Chalmers, Sherri-Ann; Arendse, Hiram; Gautier, Aude; Sharratt, Peter; Fuller, Barry; Hodgson, Humphrey

2013-01-01

Liver failure is an increasing problem. Donor-organ shortage results in patients dying before receiving a transplant. Since the liver can regenerate, alternative therapies providing temporary liver-support are sought. A bioartificial-liver would temporarily substitute function in liver failure buying time for liver regeneration/organ-procurement. Our aim: to develop a prototype bioartificial-liver-machine (BAL) comprising a human liver-derived cell-line, cultured to phenotypic competence and deliverable in a clinical setting to sites distant from its preparation. The objective of this study was to determine whether its use would improve functional parameters of liver failure in pigs with acute liver failure, to provide proof-of-principle. HepG2cells encapsulated in alginate-beads, proliferated in a fluidised-bed-bioreactor providing a biomass of 4–6×1010cells, were transported from preparation-laboratory to point-of-use operating theatre (6000miles) under perfluorodecalin at ambient temperature. Irreversible ischaemic liver failure was induced in anaesthetised pigs, after portal-systemic-shunt, by hepatic-artery-ligation. Biochemical parameters, intracranial pressure, and functional-clotting were measured in animals connected in an extracorporeal bioartificial-liver circuit. Efficacy was demonstrated comparing outcomes between animals connected to a circuit containing alginate-encapsulated cells (Cell-bead BAL), and those connected to circuit containing alginate capsules without cells (Empty-bead BAL). Cells of the biomass met regulatory standards for sterility and provenance. All animals developed progressive liver-failure after ischaemia induction. Efficacy of BAL was demonstrated since animals connected to a functional biomass (+ cells) had significantly smaller rises in intracranial pressure, lower ammonia levels, more bilirubin conjugation, improved acidosis and clotting restoration compared to animals connected to the circuit without cells. In the +cell group, human proteins accumulated in pigs' plasma. Delivery of biomass using a short-term cold-chain enabled transport and use without loss of function over 3days. Thus, a fluidised-bed bioreactor containing alginate-encapsulated HepG2cell-spheroids improved important parameters of acute liver failure in pigs. The system can readily be up-scaled and transported to point-of-use justifying development at clinical scale. PMID:24367515

First Experiences with the New Chalmers Gasifier

NASA Astrophysics Data System (ADS)

Thunman, H.; Seemann, M. C.

During summer 2007 a 2-6 MWth indirect gasification section was integrated into the loop of the existing 82➀2 MWth circulating fluidized bed boiler at Chalmers University. With help of a particle distributor the gasification unit is connected to the loop after the cyclone. Hot bed material entrained from the boiler is so transferred to the gasifier providing the heat for the production of a nearly nitrogen free product gas. Non-gasified char is returned together with the bed material into the boiler and converted. Biomass can be fed into both sections; the boiler and the gasifier. The gasification is separated from the boiler via two loop seals and a particle distributer, directing particles either back to the boiler or into the gasification section. For that reason the CFB boiler can be operated even after the retrofit independently, just like before, or in combined combustion/gasification mode. This possibility keeps the risk for a retrofit low. As, furthermore, the investment costs for the integration are considerably lower than standalone gasification units of that size, the retrofit is an easy way to extend the potential of a CFB Boiler towards bi- and tri-generation (heat, power, fuel) and enter new markets.

Optimization of Computational Performance and Accuracy in 3-D Transient CFD Model for CFB Hydrodynamics Predictions

NASA Astrophysics Data System (ADS)

Rampidis, I.; Nikolopoulos, A.; Koukouzas, N.; Grammelis, P.; Kakaras, E.

2007-09-01

This work aims to present a pure 3-D CFD model, accurate and efficient, for the simulation of a pilot scale CFB hydrodynamics. The accuracy of the model was investigated as a function of the numerical parameters, in order to derive an optimum model setup with respect to computational cost. The necessity of the in depth examination of hydrodynamics emerges by the trend to scale up CFBCs. This scale up brings forward numerous design problems and uncertainties, which can be successfully elucidated by CFD techniques. Deriving guidelines for setting a computational efficient model is important as the scale of the CFBs grows fast, while computational power is limited. However, the optimum efficiency matter has not been investigated thoroughly in the literature as authors were more concerned for their models accuracy and validity. The objective of this work is to investigate the parameters that influence the efficiency and accuracy of CFB computational fluid dynamics models, find the optimum set of these parameters and thus establish this technique as a competitive method for the simulation and design of industrial, large scale beds, where the computational cost is otherwise prohibitive. During the tests that were performed in this work, the influence of turbulence modeling approach, time and space density and discretization schemes were investigated on a 1.2 MWth CFB test rig. Using Fourier analysis dominant frequencies were extracted in order to estimate the adequate time period for the averaging of all instantaneous values. The compliance with the experimental measurements was very good. The basic differences between the predictions that arose from the various model setups were pointed out and analyzed. The results showed that a model with high order space discretization schemes when applied on a coarse grid and averaging of the instantaneous scalar values for a 20 sec period, adequately described the transient hydrodynamic behaviour of a pilot CFB while the computational cost was kept low. Flow patterns inside the bed such as the core-annulus flow and the transportation of clusters were at least qualitatively captured.

Characteristics of ash and particle emissions during bubbling fluidised bed combustion of three types of residual forest biomass.

PubMed

Ribeiro, João Peres; Vicente, Estela Domingos; Alves, Célia; Querol, Xavier; Amato, Fulvio; Tarelho, Luís A C

2017-04-01

Combustion of residual forest biomass (RFB) derived from eucalypt (Eucalyptus globulus), pine (Pinus pinaster) and golden wattle (Acacia longifolia) was evaluated in a pilot-scale bubbling fluidised bed reactor (BFBR). During the combustion experiments, monitoring of temperature, pressure and exhaust gas composition has been made. Ash samples were collected at several locations along the furnace and flue gas treatment devices (cyclone and bag filter) after each combustion experiment and were analysed for their unburnt carbon content and chemical composition. Total suspended particles (TSP) in the combustion flue gas were evaluated at the inlet and outlet of cyclone and baghouse filter and further analysed for organic and elemental carbon, carbonates and 57 chemical elements. High particulate matter collection efficiencies in the range of 94-99% were observed for the baghouse, while removal rates of only 1.4-17% were registered for the cyclone. Due to the sand bed, Si was the major element in bottom ashes. Fly ashes, in particular those from eucalypt combustion, were especially rich in CaO, followed by relevant amounts of SiO 2 , MgO and K 2 O. Ash characteristics varied among experiments, showing that their inorganic composition strongly depends on both the biomass composition and combustion conditions. Inorganic constituents accounted for TSP mass fractions up to 40 wt%. Elemental carbon, organic matter and carbonates contributed to TSP mass fractions in the ranges 0.58-44%, 0.79-78% and 0.01-1.7%, respectively.

Comparion of Mercury Emissions Between Circulating Fluidized Bed Boiler and Pulverized Coal Boiler

NASA Astrophysics Data System (ADS)

Wang, Y. J.; Duan, Y. F.; Zhao, C. S.

Mercury emissions between a circulating fluidized bed (CFB) utility boiler and two pulverized coal (PC) boilers equipped with electrostatic precipitators (ESP) were in situ measured and compared. The standard Ontario Hydro Method (OHM) was used to sample the flue gas before and after the ESP. Various mercury speciations such as Hg0, Hg2+ and Hgp in flue gas and total mercury in fly ashes were analyzed. The results showed that the mercury removal rate of the CFB boiler is nearly 100%; the mercury emission in stack is only 0.028 g/h. However, the mercury removal rates of the two PC boilers are 27.56% and 33.59% respectively, the mercury emissions in stack are 0.80 and 51.78 g/h respectively. It concluded that components of the ESP fly ashes especially their unburnt carbons have remarkable influence on mercury capture. Pore configurations of fine fly ash particles have non-ignored impacts on mercury emissions.

Steady and unsteady fluidised granular flows down slopes

NASA Astrophysics Data System (ADS)

Jessop, D. E.; Hogg, A. J.; Gilbertson, M. A.; Schoof, C.

2017-09-01

Fluidisation is the process by which the weight of a bed of particles is supported by a gas flow passing through it from below. When fluidised materials flow down an incline, the dynamics of the motion differ from their non-fluidised counterparts because the granular agitation is no longer required to support the weight of the flowing layer. Instead, the weight is borne by the imposed gas flow and this leads to a greatly increased flow mobility. In this paper, a framework is developed to model this two phase motion by incorporating a kinetic theory description for the particulate stresses generated by the flow. In addition to calculating numerical solutions for fully developed flows, it is shown that for sufficiently thick flows there is often a local balance between the production and dissipation of the granular temperature. This phenomenon permits an asymptotic reduction of the full governing equations and the identification of a simple state in which the volume fraction of the flow is uniform. The results of the model are compared with new experimental measurements of the internal velocity profiles of steady granular flows down slopes. The distance covered with time by unsteady granular flows down slopes and along horizontal surfaces and their shapes are also measured and compared with theoretical predictions developed for flows that are thin relative to their streamwise extent. For the horizontal flows, it was found that resistance from the sidewalls was required in addition to basal resistance to capture accurately the unsteady evolution of the front position and the depth of the current and for situations in which side-wall drag dominates, similarity solutions are found for the experimentally-measured motion.

High-rate sulphidogenic fluidised-bed treatment of metal-containing wastewater at high temperature.

PubMed

Sahinkaya, E; Ozkaya, B; Kaksonen, A H; Puhakka, J A

2007-01-01

The applicability of fluidised-bed reactor (FBR) based sulphate reducing bioprocess was investigated for the treatment of iron containing (40-90 mg/L) acidic wastewater at 65 degrees C. The FBR was inoculated with sulphate-reducing bacteria (SRB) originally enriched from a hot mining environment. Ethanol or acetate was supplemented as carbon and electron source for the SRB. A rapid startup with 99.9, 46 and 29% ethanol, sulphate and acetate removals, in respective order, was observed even after 6 days. Iron was almost completely removed with a rate of 90 mg/L.d. The feed pH was decreased gradually from its initial value of 6 to around 3.7 during 100 days of operation. The wastewater pH of 4.3-4.4 was neutralised by the alkalinity produced in acetate oxidation and the average effluent pH was 7.8 +/- 0.8. Although ethanol removal was complete, acetate accumulated. Later the FBR was fed with acetate only. Although acetate was present in the reactor for 295 days, its oxidation rates did not improve, which may be due to low growth rate and poor attachment ability of acetate oxidising SRB. Hence, the oxidation of acetate is the rate limiting step in the sulphidogenic ethanol oxidation by the thermophilic SRB.

Nutrients removal in hybrid fluidised bed bioreactors operated with aeration cycles.

PubMed

Martin, Martin; Enríquez, L López; Fernández-Polanco, M; Villaverde, S; Garcia-Encina, P A

2007-01-01

Abstract Two hybrid fluidised bed reactors filled with sepiolite and granular activated carbon (GAC) were operated with short cycled aeration for removing organic matter, total nitrogen and phosphorous, respectively. Both reactors were continuously operated with synthetic and/or industrial wastewater containing 350-500 mg COD/L, 110-130 mg NKT/L, 90-100 mg NH3-N/L and 12-15 mg P/L for 8 months. The reactor filled with sepiolite, treating only synthetic wastewater, removed COD, ammonia, total nitrogen and phosphorous up to 88, 91, 55 and 80% with a hydraulic retention time (HRT) of 10 h, respectively. These efficiencies correspond to removal rates of 0.95 kgCODm(-3)d(-1) and 0.16 kg total N m(-3)d(-1). The reactor filled with GAC was operated for 4 months with synthetic wastewater and 4 months with industrial wastewater, removing 98% of COD, 96% of ammonia, and 66% of total nitrogen, with an HRT of 13.6 h. No significant phosphorous removing activity was observed in this reactor. Microbial communities growing with both reactors were followed using polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE) techniques. The microbial fingerprints, i.e. DGGE profiles, indicated that biological communities in both reactors were stable along the operational period even when the operating conditions were changed.

Comparison of coal/solid recovered fuel (SRF) with coal/refuse derived fuel (RDF) in a fluidised bed reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wagland, S.T.; Kilgallon, P.; Coveney, R.

2011-06-15

An experimental study was undertaken to compare the differences between municipal solid waste (MSW) derived solid recovered fuel (SRF) (complying with CEN standards) and refuse derived fuel (RDF). Both fuels were co-combusted with coal in a 50 kW fluidised bed combustor and the metal emissions were compared. Synthetic SRF was prepared in the laboratory by grinding major constituents of MSW such as paper, plastic, textile and wood. RDF was obtained from a local mechanical treatment plant. Heavy metal emissions in flue gas and ash samples from the (coal + 10% SRF) fuel mixture were found to be within the acceptablemore » range and were generally lower than that obtained for coal + 10% RDF fuel mixture. The relative distribution of heavy metals in ash components and the flue gas stream shows the presence of a large fraction (up to 98%) of most of the metals in the ash (except Hg and As). Thermo-gravimetric (TG) analysis of SRF constituents was performed to understand the behaviour of fuel mixtures in the absence and presence of air. The results obtained from the experimental study will enhance the confidence of fuel users towards using MSW-derived SRF as an alternative fuel.« less

Experimental investigation on heat transfer and frictional characteristics of vertical upward rifled tube in supercritical CFB boiler

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Dong; Pan, Jie; Zhu, Xiaojing

2011-02-15

Water wall design is a key issue for supercritical Circulating Fluidized Bed (CFB) boiler. On account of the good heat transfer performance, rifled tube is applied in the water wall design of a 600 MW supercritical CFB boiler in China. In order to investigate the heat transfer and frictional characteristics of the rifled tube with vertical upward flow, an in-depth experiment was conducted in the range of pressure from 12 to 30 MPa, mass flux from 230 to 1200 kg/(m{sup 2} s), and inner wall heat flux from 130 to 720 kW/m{sup 2}. The wall temperature distribution and pressure dropmore » in the rifled tube were obtained in the experiment. The normal, enhanced and deteriorated heat transfer characteristics were also captured. In this paper, the effects of pressure, inner wall heat flux and mass flux on heat transfer characteristics are analyzed, the heat transfer mechanism and the frictional resistance performance are discussed, and the corresponding empirical correlations are presented. The experimental results show that the rifled tube can effectively prevent the occurrence of departure from nucleate boiling (DNB) and keep the tube wall temperature in a permissible range under the operating condition of supercritical CFB boiler. (author)« less

Experimental Research on the Dense CFB's Riser and the Simulation Based on the EMMS Model

NASA Astrophysics Data System (ADS)

Wang, X. Y.; Wang, S. D.; Fan, B. G.; Liao, L. L.; Jiang, F.; Xu, X.; Wu, X. Z.; Xiao, Y. H.

2010-03-01

The flow structure in the CFB (circulating fluidized bed) riser has been investigated. Experimental studies were performed in a cold square section unit with 270 mm×270 mm×10 m. Since the drag force model based on homogeneous two-phase flow such as the Gidaspow drag model could not depict the heterogeneous structures of the gas-solid flow, the structure-dependent energy-minimization multi-scale (EMMS) model based on the heterogenerity was applied in the paper and a revised drag force model based on the EMMS model was proposed. A 2D two-fluid model was used to simulate a bench-scale square cross-section riser of a cold CFB. The typical core-annulus structure and the back-mixing near the wall of the riser were observed and the assembly and fragmentation processes of clusters were captured. By comparing with the Gidaspow drag model, the results obtained by the revised drag model based on EMMS shows better consistency with the experimental data. The model can also depict the difference from the two exit configurations. This study once again proves the key role of drag force in CFD (Computational Fluid Dynamics) simulation and also shows the availability of the revised drag model to describe the gas-solid flow in CFB risers.

Fluidised Bed Microencapsulation of Ascorbic Acid: Effectiveness of Protection under Simulated Tropical Storage Conditions

DTIC Science & Technology

2012-01-01

example, probiotics (Kailasapathy, 2002; Rokka and Rantamäki, 2010), folic acid (Madziva et al., 2006) and ascorbic acid (Wijaya et al., 2011...Kailasapathy, K. 2002. Microencapsulation of Probiotic Bacteria: Technology and Potential Applications. Current Issues in Intestinal Microbiology, 3: 39-48...Re´, M. I. 1998. Microencapsulation by spray drying. Drying Technology, 16:1195–1236. Rokka, S., and Rantamäki, P. 2010. Protecting probiotic

Process Analysis of Lignite Circulating Fluidized Bed Boiler Coupled with Pyrolysis Topping

NASA Astrophysics Data System (ADS)

Wang, Baoqun; Dong, Li; Wang, Yin; Matsuzawa, Y.; Xu, Guangwen

We developed a comprehensive process model in ASPEN Plus to simulate the energy and mass balances of a lignite-fueled atmospheric circulating fluidized bed (CFB) boiler integrated with coal predrying and pyrolysis topping. In this model, it is assumed that the heat from exhausted flue gas was employed for coal predrying, and the sensible heat derived from circulated bed material was used for the pyrolysis topping (endothermic process). The simulation was conducted with respectto the Yunnan Kaiyuan CFB boiler, and two representative lignite coals from Xiao Long Tan (XLT) and Xin Shao (XS) were considered. The result shows that the predrying of coal with the sensible heat of above 363 K from flue gas, the amount of coal consumed in the boiler can be reduced by 3.5% and 5.3% for XLT lignite and XS lignite, respectively. It was also found that integration of pyrolysis topping with the boiler increased the coal consumption of the boiler, and the extent of consumption-increase varies with the yields of tar and gas in the pyrolysis topping process. For agas yield of 5.2% and a tar yield of 5-6%, the consumption of XS lignite increased by about 20% comparing to that in the case without topping.

Numerical analysis of flow instability in the water wall of a supercritical CFB boiler with annular furnace

NASA Astrophysics Data System (ADS)

Xie, Beibei; Yang, Dong; Xie, Haiyan; Nie, Xin; Liu, Wanyu

2016-08-01

In order to expand the study on flow instability of supercritical circulating fluidized bed (CFB) boiler, a new numerical computational model considering the heat storage of the tube wall metal was presented in this paper. The lumped parameter method was proposed for wall temperature calculation and the single channel model was adopted for the analysis of flow instability. Based on the time-domain method, a new numerical computational program suitable for the analysis of flow instability in the water wall of supercritical CFB boiler with annular furnace was established. To verify the code, calculation results were respectively compared with data of commercial software. According to the comparisons, the new code was proved to be reasonable and accurate for practical engineering application in analysis of flow instability. Based on the new program, the flow instability of supercritical CFB boiler with annular furnace was simulated by time-domain method. When 1.2 times heat load disturbance was applied on the loop, results showed that the inlet flow rate, outlet flow rate and wall temperature fluctuated with time eventually remained at constant values, suggesting that the hydrodynamic flow was stable. The results also showed that in the case of considering the heat storage, the flow in the water wall is easier to return to stable state than without considering heat storage.

Numerical Modeling of Reactive Multiphase Flow for FCC and Hot Gas Desulfurization Circulating Fluidized Beds

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, Aubrey L.

2005-07-01

This work was carried out to understand the behavior of the solid and gas phases in a CFB riser. Only the riser is modeled as a straight pipe. A model with linear algebraic approximation to solids viscosity of the form, {musubs} = 5.34{epsisubs}, ({espisubs} is the solids volume fraction) with an appropriate boundary condition at the wall obtained by approximate momentum balance solution at the wall to acount for the solids recirculation is tested against experimental results. The work done was to predict the flow patterns in the CFB risers from available experimental data, including data from a 7.5-cm-ID CFBmore » riser at the Illinois Institute of Technology and data from a 20.0-cm-ID CFB riser at the Particulate Solid Research, Inc., facility. This research aims at modeling the removal of hydrogen sulfide from hot coal gas using zinc oxide as the sorbent in a circulating fluidized bed and in the process indentifying the parameters that affect the performance of the sulfidation reactor. Two different gas-solid reaction models, the unreacted shrinking core (USC) and the grain model were applied to take into account chemical reaction resistances. Also two different approaches were used to affect the hydrodynamics of the process streams. The first model takes into account the effect of micro-scale particle clustering by adjusting the gas-particle drag law and the second one assumes a turbulent core with pseudo-steady state boundary condition at the wall. A comparison is made with experimental results.« less

Low temperature circulating fluidized bed gasification and co-gasification of municipal sewage sludge. Part 2: Evaluation of ash materials as phosphorus fertilizer.

PubMed

Thomsen, Tobias Pape; Hauggaard-Nielsen, Henrik; Gøbel, Benny; Stoholm, Peder; Ahrenfeldt, Jesper; Henriksen, Ulrik B; Müller-Stöver, Dorette Sophie

2017-08-01

The study is part 2 of 2 in an investigation of gasification and co-gasification of municipal sewage sludge in low temperature gasifiers. In this work, solid residuals from thermal gasification and co-gasification of municipal sewage sludge were investigated for their potential use as fertilizer. Ashes from five different low temperature circulating fluidized bed (LT-CFB) gasification campaigns including two mono-sludge campaigns, two sludge/straw mixed fuels campaigns and a straw reference campaign were compared. Experiments were conducted on two different LT-CFBs with thermal capacities of 100kW and 6MW, respectively. The assessment included: (i) Elemental composition and recovery of key elements and heavy metals; (ii) content of total carbon (C) and total nitrogen (N); (iii) pH; (iv) water extractability of phosphorus after incubation in soil; and (v) plant phosphorus response measured in a pot experiment with the most promising ash material. Co-gasification of straw and sludge in LT-CFB gasifiers produced ashes with a high content of recalcitrant C, phosphorus (P) and potassium (K), a low content of heavy metals (especially cadmium) and an improved plant P availability compared to the mono-sludge ashes, thereby showing the best fertilizer qualities among all assessed materials. It was also found that bottom ashes from the char reactor contained even less heavy metals than cyclone ashes. It is concluded that LT-CFB gasification and co-gasification is a highly effective way to purify and sanitize sewage sludge for subsequent use in agricultural systems. Copyright © 2017 Elsevier Ltd. All rights reserved.

Postcombustion and its influences in 135 MWe CFB boilers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shaohua Li; Hairui Yang; Hai Zhang

2009-09-15

In the cyclone of a circulating fluidized bed (CFB) boiler, a noticeable increment of flue gas temperature, caused by combustion of combustible gas and unburnt carbon content, is often found. Such phenomenon is defined as post combustion, and it could introduce overheating of reheated and superheated steam and extra heat loss of exhaust flue gas. In this paper, mathematical modeling and field measurements on post combustion in 135MWe commercial CFB boilers were conducted. A novel one-dimensional combustion model taking post combustion into account was developed. With this model, the overall combustion performance, including size distribution of various ashes, temperature profile,more » and carbon content profiles along the furnace height, heat release fraction in the cyclone and furnace were predicted. Field measurements were conducted by sampling gas and solid at different positions in the boiler under different loads. The measured data and corresponding model-calculated results were compared. Both prediction and field measurements showed post combustion introduced a temperature increment of flue gas in the cyclone of the 135MWe CFB boiler in the range of 20-50{sup o}C when a low-volatile bituminous coal was fired. Although it had little influence on ash size distribution, post combustion had a remarkable influence on the carbon content profile and temperature profile in the furnace. Moreover, it introduced about 4-7% heat release in the cyclone over the total heat release in the boiler. This fraction slightly increased with total air flow rate and boiler load. Model calculations were also conducted on other two 135MWe CFB boilers burning lignite and anthracite coal, respectively. The results confirmed that post combustion was sensitive to coal type and became more severe as the volatile content of the coal decreased. 15 refs., 11 figs., 4 tabs.« less

Attrition of fluid cracking catalyst in fluidized beds

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boerefijn, R.; Ghadiri, M.

1996-12-31

Particle attrition in fluid catalytic cracking units causes loss of catalyst, which could amount to a few tonnes per day! The dependence of attrition on the process conditions and catalyst properties is therefore of great industrial interest, but it is however not well established at present. The process of attrition in the jetting area of fluidised beds is addressed and the attrition test method of Forsythe & Hertwig is analysed in this paper. This method is used commonly to assess the attrition propensity of FCC powder, whereby the attrition rate in a single jet at very high orifice velocity (300more » m s{sup -1}) is measured. There has been some concern on the relevance of this method to attrition in FCC units. Therefore, a previously-developed model of attrition in the jetting region is employed in an attempt to establish a solid basis of interpretation of the Forsythe & Hertwig test and its application as an industrial standard test. The model consists of two parts. The first part predicts the solids flow patterns in the jet region, simulating numerically the Forsythe & Hertwig test. The second part models the breakage of single particles upon impact. Combining these two models, thus linking single particle mechanical properties to macroscopic flow phenomena, results in the modelling of the attrition rate of particles entrained into a single high speed jet. High speed video recordings are made of a single jet in a two-dimensional fluidised bed, at up to 40500 frames per second, in order to quantify some of the model parameters. Digital analysis of the video images yields values for particle velocities and entrainment rates in the jet, which can be compared to model predictions. 15 refs., 8 figs.« less

Chemical and ecotoxicological characterization of ashes obtained from sewage sludge combustion in a fluidised-bed reactor.

PubMed

Lapa, N; Barbosa, R; Lopes, M H; Mendes, B; Abelha, P; Boavida, D; Gulyurtlu, I; Oliveira, J Santos

2007-08-17

In 1999, the DEECA/INETI and the UBiA/FCT/UNL started a researching project on the partition of heavy metals during the combustion of stabilised sewage sludge (Biogran), in a fluidised-bed reactor, and on the quality of the bottom ashes and fly ashes produced. This project was entitled Bimetal and was funded by the Portuguese Foundation for Science and Technology. In this paper only the results on the combustion of Biogran are reported. The combustion process was performed in two different trials, in which different amounts of sewage sludge and time of combustion were applied. Several ash samples were collected from the bed (bottom ashes) and from two cyclones (first cyclone and second cyclone ashes). Sewage sludge, bed material (sand) and ash samples were submitted to the leaching process defined in the European leaching standard EN 12457-2. The eluates were characterized for a set of inorganic chemical species. The ecotoxicological levels of the eluates were determined for two biological indicators (Vibrio fischeri and Daphnia magna). The results were compared with the limit values of the CEMWE French Regulation. The samples were also ranked according to an index based on the chemical characterization of the eluates. It was observed an increase of the concentration of metals along the combustion system. The ashes trapped in the second cyclone, for both combustion trials, showed the highest concentration of metals in the eluates. Chemically, the ashes of the second cyclone were the most different ones. In the ecotoxicological point of view, the ecotoxicity levels of the eluates of the ashes, for both combustion cycles, did not follow the same pattern as observed for the chemical characterization. The ashes of the first cyclone showed the highest ecotoxicity levels for V. fischeri and D. magna. This difference on chemical and ecotoxicological results proves the need for performing both chemical and ecotoxicological characterizations of the sub-products of such type of thermal processes.

Flow Regime Study in a Circulating Fluidized Bed Riser with an Abrupt Exit: [1] High Density Suspension

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mei, J.S.; Lee, G.T.; Seachman, S.M.

2008-05-13

Flow regime study was conducted in a 0.3 m diameter, 15.5 m tall circulating fluidized bed (CFB) riser with an abrupt exit at the National Energy Technology Laboratory of the U. S. Department of Energy. A statistical designed test series was conducted including four (4) operating set points and a duplicated center point (therefore a total of 6 operating set points). Glass beads of mean diameter 200 μm and particle density of 2,430 kg/m3 were used as bed material. The CFB riser was operated at various superficial gas velocities ranging from 5.6 to 7.6 m/s and solid mass flux frommore » a low of 86 to a high of 303 kg/m2-s. Results of the apparent solids fraction profile as well as the radial particle velocity profile were analyzed in order to identify the presence of Dense Suspension Upflow (DSU) conditions. DSU regime was found to exist at the bottom of the riser, while the middle section of the riser was still exhibiting core-annular flow structure. Due to the abrupt geometry of the exit, the DSU regime was also found at the top of the riser. In addition the effects of the azimuthal angle, riser gas velocity, and mass solids flux on the particle velocity were investigated and are discussed in this paper.« less

Applications of tribology to determine attrition by wear of particulate solids in CFB systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bayham, Samuel C.; Breault, Ronald; Monazam, Esmail

In recent years, much attention has been focused on the development of novel technologies for carbon capture and chemicals production that utilize a circulating fluidized bed (CFB) configuration; examples include chemical looping combustion and circulation of temperature swing adsorbents in a CFB configuration for CO 2 capture. A major uncertainty in determining the economic feasibility of these technologies is the required solids makeup rate, which, among other factors, is due to impact and wear attrition at various locations, including standpipes, cyclones, and the gas jets in fluid beds. While correlations have been developed that estimate the attrition rates at thesemore » areas, these correlations are dependent on constants that are uncertain without extensive experiment in the corresponding unit operation. Thus, it is difficult to determine the attrition rate a priori without performing extensive experiments on the materials or scaling up entirely. In this work, the authors outline a methodology for predictive attrition based on fundamental material properties from fields of tribology—specifically, the study of wear—to the knowledge of forces and sliding distances determined from hydrodynamic models to develop basic attrition models for novel CFB systems. The equations are derived for the standpipe and cyclone, which are common components found in CFBs, and the cyclone equation is compared to experimental data of attrition in the literature. The cyclone equation derived in this work results in an abrasion rate based on (1) material properties such as particle density and hardness, (2) inlet velocity, and (3) cyclone geometry. According to this equation, increasing the diameter of the cyclone and the solids inlet velocity tends to increase the rate of abrasion of the catalyst, while decreasing the hardness increases the abrasion rate. The functionality of the increasing attrition rate with velocity increase implies that increasing the efficiency of the cyclone may also increase the attrition rate via abrasion. With modifications to the severity coefficient term to include the solids loading, the cyclone equation derived in this work fits data from Reppenhagen and Werther with a coefficient of determination (R2) of 92%.« less

Applications of tribology to determine attrition by wear of particulate solids in CFB systems

DOE PAGES

Bayham, Samuel C.; Breault, Ronald; Monazam, Esmail

2016-11-03

In recent years, much attention has been focused on the development of novel technologies for carbon capture and chemicals production that utilize a circulating fluidized bed (CFB) configuration; examples include chemical looping combustion and circulation of temperature swing adsorbents in a CFB configuration for CO 2 capture. A major uncertainty in determining the economic feasibility of these technologies is the required solids makeup rate, which, among other factors, is due to impact and wear attrition at various locations, including standpipes, cyclones, and the gas jets in fluid beds. While correlations have been developed that estimate the attrition rates at thesemore » areas, these correlations are dependent on constants that are uncertain without extensive experiment in the corresponding unit operation. Thus, it is difficult to determine the attrition rate a priori without performing extensive experiments on the materials or scaling up entirely. In this work, the authors outline a methodology for predictive attrition based on fundamental material properties from fields of tribology—specifically, the study of wear—to the knowledge of forces and sliding distances determined from hydrodynamic models to develop basic attrition models for novel CFB systems. The equations are derived for the standpipe and cyclone, which are common components found in CFBs, and the cyclone equation is compared to experimental data of attrition in the literature. The cyclone equation derived in this work results in an abrasion rate based on (1) material properties such as particle density and hardness, (2) inlet velocity, and (3) cyclone geometry. According to this equation, increasing the diameter of the cyclone and the solids inlet velocity tends to increase the rate of abrasion of the catalyst, while decreasing the hardness increases the abrasion rate. The functionality of the increasing attrition rate with velocity increase implies that increasing the efficiency of the cyclone may also increase the attrition rate via abrasion. With modifications to the severity coefficient term to include the solids loading, the cyclone equation derived in this work fits data from Reppenhagen and Werther with a coefficient of determination (R2) of 92%.« less

The simulation and experimental validation on gas-solid two phase flow in the riser of a dense fluidized bed

NASA Astrophysics Data System (ADS)

Wang, Xue-Yao; Jiang, Fan; Xu, Xiang; Wang, Sheng-Dian; Fan, Bao-Guo; Xiao, Yun-Han

2009-06-01

Gas-solid flow in dense CFB (circulating fluidized bed)) riser under the operating condition, superficial gas 15.5 m/s and solid flux 140 kg/m2s using Geldart B particles (sand) was investigated by experiments and CFD (computational fluid dynamics) simulation. The overall and local flow characteristics are determined using the axial pressure profiles and solid concentration profiles. The cold experimental results indicate that the axial solid concentration distribution contains a dilute region towards the up-middle zone and a dense region near the bottom and the top exit zones. The typical core-annulus structure and the back-mixing phenomenon near the wall of the riser can be observed. In addition, owing to the key role of the drag force of gas-solid phase, a revised drag force coefficient, based on the EMMS (energy-minimization multi-scale) model which can depict the heterogeneous character of gas-solid two phase flow, was proposed and coupled into the CFD control equations. In order to find an appropriate drag force model for the simulation of dense CFB riser, not only the revised drag force model but some other kinds of drag force model were used in the CFD. The flow structure, solid concentration, clusters phenomenon, fluctuation of two phases and axial pressure drop were analyzed. By comparing the experiment with the simulation, the results predicted by the EMMS drag model showed a better agreement with the experimental axial average pressure drop and apparent solid volume fraction, which proves that the revised drag force based on the EMMS model is an appropriate model for the dense CFB simulation.

Analysis of the acceleration region in a circulating fluidized bed riser operating above fast fluidization velocities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Monazam, E.R.; Shadle, L.J.

2008-11-05

In commercial circulating fluidized bed (CFB) processes the acceleration zone greatly contributes to solids mixing, gas and solids dispersion, and particle residence times. A new analysis was developed to describe the relative gas-solids concentration in the acceleration region of a transport system with air as the fluidizing agent for Geldart-type B particles. A theoretical expression was derived from a drag relationship and momentum and continuity equations to describe the evolution of the gas-solids profile along the axial direction. The acceleration zone was characterized using nondimensional analysis of the continuum equations (balances of masses and momenta) that described multiphase flows. Inmore » addition to acceleration length, the boundary condition for the solids fraction at the bottom of the riser and the fully developed regions were measured using an industrial scale CFB of 0.3 m diameter and 15 m tall. The operating factors affecting the flow development in the acceleration region were determined for three materials of various sizes and densities in core annular and dilute regimes of the riser. Performance data were taken from statistically designed experiments over a wide range of Fr (0.5-39), Re (8-600), Ar (29-3600), load ratio (0.2-28), riser to particle diameter ratio (375-5000), and gas to solids density ratio (138-1381). In this one-dimensional system of equations, velocities and solid fractions were assumed to be constant over any cross section. The model and engineering correlations were compared with literature expressions to assess their validity and range of applicability. These expressions can be used as tools for simulation and design of a CFB riser and can also be easily coupled to a kinetics model for process simulation.« less

Gaseous emissions during concurrent combustion of biomass and non-recyclable municipal solid waste

PubMed Central

2011-01-01

Background Biomass and municipal solid waste offer sustainable sources of energy; for example to meet heat and electricity demand in the form of combined cooling, heat and power. Combustion of biomass has a lesser impact than solid fossil fuels (e.g. coal) upon gas pollutant emissions, whilst energy recovery from municipal solid waste is a beneficial component of an integrated, sustainable waste management programme. Concurrent combustion of these fuels using a fluidised bed combustor may be a successful method of overcoming some of the disadvantages of biomass (high fuel supply and distribution costs, combustion characteristics) and characteristics of municipal solid waste (heterogeneous content, conflict with materials recycling). It should be considered that combustion of municipal solid waste may be a financially attractive disposal route if a 'gate fee' value exists for accepting waste for combustion, which will reduce the net cost of utilising relatively more expensive biomass fuels. Results Emissions of nitrogen monoxide and sulphur dioxide for combustion of biomass are suppressed after substitution of biomass for municipal solid waste materials as the input fuel mixture. Interactions between these and other pollutants such as hydrogen chloride, nitrous oxide and carbon monoxide indicate complex, competing reactions occur between intermediates of these compounds to determine final resultant emissions. Conclusions Fluidised bed concurrent combustion is an appropriate technique to exploit biomass and municipal solid waste resources, without the use of fossil fuels. The addition of municipal solid waste to biomass combustion has the effect of reducing emissions of some gaseous pollutants. PMID:21284885

A comparative assessment of waste incinerators in the UK.

PubMed

Nixon, J D; Wright, D G; Dey, P K; Ghosh, S K; Davies, P A

2013-11-01

The uptake in Europe of Energy from Waste (EfW) incinerator plants has increased rapidly in recent years. In the UK, 25 municipal waste incinerators with energy recovery are now in operation; however, their waste supply chains and business practices vary significantly. With over a hundred more plant developments being considered it is important to establish best business practices for ensuring efficient environmental and operational performance. By reviewing the 25 plants we identify four suitable case study plants to compare technologies (moving grate, fluidised bed and rotary kiln), plant economics and operations. Using data collected from annual reports and through interviews and site visits we provide recommendations for improving the supply chain for waste incinerators and highlight the current issues and challenges faced by the industry. We find that plants using moving grate have a high availability of 87-92%. However, compared to the fluidised bed and rotary kiln, quantities of bottom ash and emissions of hydrogen chloride and carbon monoxide are high. The uptake of integrated recycling practices, combined heat and power, and post incineration non-ferrous metal collections needs to be increased among EfW incinerators in the UK. We conclude that one of the major difficulties encountered by waste facilities is the appropriate selection of technology, capacity, site, waste suppliers and heat consumers. This study will be of particular value to EfW plant developers, government authorities and researchers working within the sector of waste management. Copyright © 2013 Elsevier Ltd. All rights reserved.

Experimental Study and CFD Simulation of a 2D Circulating Fluidized Bed

NASA Astrophysics Data System (ADS)

Kallio, S.; Guldén, M.; Hermanson, A.

Computational fluid dynamics (CFD) gains popularity in fluidized bed modeling. For model validation, there is a need of detailed measurements under well-defined conditions. In the present study, experiments were carried out in a 40 em wide and 3 m high 2D circulating fluidized bed. Two experiments were simulated by means of the Eulerian multiphase models of the Fluent CFD software. The vertical pressure and solids volume fraction profiles and the solids circulation rate obtained from the simulation were compared to the experimental results. In addition, lateral volume fraction profiles could be compared. The simulated CFB flow patterns and the profiles obtained from simulations were in general in a good agreement with the experimental results.

Desulfurization characteristics of rapidly hydrated sorbents with various adhesive carrier particles for a semidry CFB-FGD system.

PubMed

You, Changfu; Li, Yuan

2013-03-19

Semidry flue gas desulfurization (FGD) experiments were conducted using rapidly hydrated sorbents with four different adhesive carrier particles: circulation ash from a circulating fluidized bed boiler (CFBB circulation ash), fly ash from the first electrical field of the electrostatic precipitator of a circulating fluidized bed boiler (CFBB ESP ash), fly ash from a chain boiler (chain boiler ash), and river sand smaller than 1 mm. The influences of various adhesive carrier particles and operating conditions on the desulfurization characteristics of the sorbents were investigated, including sprayed water, reaction temperature, and the ratio of calcium to sulfur (Ca/S). The experimental results indicated that the rapidly hydrated sorbents had better desulfurization characteristics by using adhesive carrier particles which possessed better pore, adhesion, and fluidization characteristics. The desulfurization efficiency of the system increased as the reaction temperature decreased, it improved from 35% to 90% as the mass flow rate of the sprayed water increased from 0 to 10 kg/h, and it increased from 65.6% to 82.7% as Ca/S increased from 1.0 to 2.0. Based on these findings, a new semidry circulating fluidized bed (CFB)-FGD system using rapidly hydrated sorbent was developed. Using the rapidly hydrated sorbent, this system uses a cyclone separator instead of an ESP or a bag filter to recycle the sorbent particles, thereby decreasing the system flow resistance, saving investment and operating costs of the solids collection equipment.

Heat transfer and hydrodynamic analysis in an industrial circulating fluidized bed boiler

DOE Office of Scientific and Technical Information (OSTI.GOV)

Di Maggio, T.; Piedfer, O.; Jestin, L.

In order to scale-up Circulating Fluidized Bed boilers (up to 600 MWe), Electricite de France has initiated a Research and Development program including: laboratory work on mock-up, numerical modeling and on-site tests in the 125 MWe CFB Emile Huchet plant. This paper is devoted to on-site measurements analysis in two main components of this industrial unit: the external fluidized bed heat exchangers and the backpass. This study particularly concerns hydrodynamics and heat transfer with the final target of developing a physical model of a CFB unit. The first part of this paper describes the specific instrumentation set up on externalmore » fluidized bed heat exchangers. The comparison between experimental data collected on these heat exchangers and the theoretical heat transfer models mainly used, shows a great difference about the value of the overall heat transfer coefficient. To explain this discrepancy, the particle flow pattern initially used in the thermal balance calculation is modified and a solid bypass is introduced. The analysis of the by-pass behavior, connected to the geometrical and operating parameters of each exchanger, confirms the particle flow pattern suggested. The second part of this paper shows an analysis of the specific measurements set up on the backpass to study heat transfer. The physical model of heat transfer used to assess the importance of each convection, radiation and conduction components is presented. This model allows one to assess the influence of heat exchangers design on heat transfer. Moreover, the analysis of heat transfer variations during sweeping cycles gives the amount of dust that is removed from the heat exchanger tubes. These results are used to evaluate the amount of power that can be recovered by optimizing both design and sweeping of the backpass.« less

NUCLA Circulating Atmospheric Fluidized Bed Demonstration Project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Keith, Raymond E.; Heller, Thomas J.; Bush, Stuart A.

1991-01-01

This Annual Report on Colorado-Ute Electric Association's NUCLA Circulating Fluidized Bed (CFB) Demonstration Program covers the period from February 1987 through December 1988. The outline for presentation in this report includes a summary of unit operations along with individual sections covering progress in study plan areas that commenced during this reporting period. These include cold-mode shakedown and calibration, plant commercial performance statistics, unit start-up (cold), coal and limestone preparation and handling, ash handling system performance and operating experience, tubular air heater, baghouse operation and performance, materials monitoring, and reliability monitoring. During this reporting period, the coal-mode shakedown and calibration planmore » was completed. (VC)« less

Investigation of gas-solids flow in a circulating fluidized bed using 3D electrical capacitance tomography

NASA Astrophysics Data System (ADS)

Mao, Mingxu; Ye, Jiamin; Wang, Haigang; Yang, Wuqiang

2016-09-01

The hydrodynamics of gas-solids flow in the bottom of a circulating fluidized bed (CFB) are complicated. Three-dimensional (3D) electrical capacitance tomography (ECT) has been used to investigate the hydrodynamics in risers of different shapes. Four different ECT sensors with 12 electrodes each are designed according to the dimension of risers, including two circular ECT sensors, a square ECT sensor and a rectangular ECT sensor. The electrodes are evenly arranged in three planes to obtain capacitance in different heights and to reconstruct the 3D images by linear back projection (LBP) algorithm. Experiments were carried out on the four risers using sands as the solids material. The capacitance and differential pressure are measured under the gas superficial velocity from 0.6 m s-1 to 3.0 m s-1 with a step of 0.2 m s-1. The flow regime is investigated according to the solids concentration and differential pressure. The dynamic property of bubbling flows is analyzed theoretically and the performance of the 3D ECT sensors is evaluated. The experimental results show that 3D ECT can be used in the CFB with different risers to predict the hydrodynamics of gas-solids bubbling flows.

Hydrogen Production by Sorption Enhanced Steam Reforming (SESR) of Biomass in a Fluidised-Bed Reactor Using Combined Multifunctional Particles

PubMed Central

Zheng, Liya; Zhang, Zili; Fennell, Paul S.

2018-01-01

The performance of combined CO2-sorbent/catalyst particles for sorption enhanced steam reforming (SESR), prepared via a simple mechanical mixing protocol, was studied using a spout-fluidised bed reactor capable of continuous solid fuel (biomass) feeding. The influence of particle size (300–500 and 710–1000 µm), CaO loading (60–100 wt %), Ni-loading (10–40 wt %) and presence of dicalcium silicate support (22.6 wt %) on SESR process performance were investigated. The combined particles were characterised by their density, porosity and CO2 carrying capacity with the analysis by thermogravimetric analysis (TGA), Brunauer-Emmett-Teller (BET), Barrett-Joyner-Halenda (BJH) and mercury intrusion porosimetry (MIP). All experiments were conducted with continuous oak biomass feeding at a rate of 0.9 g/min ± 10%, and the reactor was operated at 660 ± 5 °C, 1 atm and 20 ± 2 vol % steam which corresponds to a steam-to-carbon ratio of 1.2:1. Unsupported combined particles containing 21.0 wt % Ni and 79 wt % CaO were the best performing sorbent/catalyst particle screened in this study, when accounting for the cost of Ni and the improvement in H2 produced by high Ni content particles. SESR tests with these combined particles produced 61 mmol H2/gbiomass (122 g H2/kgbiomass) at a purity of 61 vol %. Significant coke formation within the feeding tube and on the surfaces of the particles was observed which was attributed to the low steam to carbon ratio utilised. PMID:29883427

Characterising boiler ash from a circulating fluidised bed municipal solid waste incinerator and distribution of PCDD/F and PCB.

PubMed

Zhang, Mengmei; Buekens, Alfons; Li, Xiaodong

2018-05-31

In this study, ash samples were collected from five locations situated in the boiler of a circulating fluidised bed municipal solid waste incinerator (high- and low-temperature superheater, evaporator tubes and upper and lower economiser). These samples represent a huge range of flue gas temperatures and were characterised for their particle size distribution, surface characteristics, elemental composition, chemical forms of carbon and chlorine and distribution of polychlorinated dibenzo-p-dioxins (PCDD), dibenzofurans (PCDF) and biphenyls (PCB). Enrichment of chlorine, one of the main elements of organochlorinated pollutants, and copper, zinc and lead, major catalytic metals for dioxin-like compounds, was observed in lower-temperature ash deposits. The speciation of carbon and chlorine on ash surfaces was established, showing a positive correlation between organic chlorine and oxygen-containing carbon functional groups. The load of PCDD/F and PCB (especially dioxin-like PCB) tends to rise rapidly with falling temperature of flue gas, reaching their highest value in economiser ashes. The formation of PCDD/F congeners through the chlorophenol precursor route apparently was enhanced downstream the boiler. Principal component analysis (PCA) was applied to study the links between the ash characteristics and distribution of chloro-aromatics. The primary purpose of this study is improving the understanding of any links between the characteristics of ash from waste heat systems and its potential to form PCDD/F and PCB. The question is raised whether further characterisation of fly ash may assist to establish a diagnosis of poor plant operation, inclusive the generation, destruction and eventual emission of persistent organic pollutants (POPs).

Fluidised-bed spray-drying formulations of Candida sake CPA-1 by adding biodegradable coatings to enhance their survival under stress conditions.

PubMed

Carbó, Anna; Torres, Rosario; Usall, Josep; Solsona, Cristina; Teixidó, Neus

2017-11-01

The biocontrol agent Candida sake CPA-1 has demonstrated to be effective against several diseases on fruit. However, for application of CPA-1 under field conditions, it was necessary to mix it with a food coating to improve survival under stress conditions, as well as adherence and distribution on fruit surfaces. The objective of this study was to obtain a more competitive formulation under field conditions to be applied independently of any product. To achieve this purpose, the drying process of CPA-1 by a fluidised-bed spray-drying system together with biodegradable coatings was optimised. This approach is novel for the drying system used and the formulation obtained which was able to form a film or coating on fruit surfaces. Several substances were tested as carriers and binders, and drying temperature was optimised. The addition of protective compounds was also tested to improve survival of CPA-1 during the dehydration process. Product shelf life, biocontrol efficacy on grapes against Botrytis cinerea, and the improvement of C. sake behaviour under stress conditions were tested. The optimal temperature of drying was 55 °C and two formulations that were able to develop a coating on fruit surfaces were obtained. One of the formulations was created by using a combination of native and pregelatinised potato starch; the other formulation was obtained using maltodextrin and by adding skimmed milk and sucrose as protectant compounds. The formulated products reduced the incidence and severity of B. cinerea, and CPA-1 survival rate was increased under stress conditions of temperature and humidity.

Pyrolysis of waste tyres: A review

DOE Office of Scientific and Technical Information (OSTI.GOV)

Williams, Paul T., E-mail: p.t.williams@leeds.ac.uk

2013-08-15

Graphical abstract: - Highlights: • Pyrolysis of waste tyres produces oil, gas and char, and recovered steel. • Batch, screw kiln, rotary kiln, vacuum and fluidised-bed are main reactor types. • Product yields are influenced by reactor type, temperature and heating rate. • Pyrolysis oils are complex and can be used as chemical feedstock or fuel. • Research into higher value products from the tyre pyrolysis process is reviewed. - Abstract: Approximately 1.5 billion tyres are produced each year which will eventually enter the waste stream representing a major potential waste and environmental problem. However, there is growing interest inmore » pyrolysis as a technology to treat tyres to produce valuable oil, char and gas products. The most common reactors used are fixed-bed (batch), screw kiln, rotary kiln, vacuum and fluidised-bed. The key influence on the product yield, and gas and oil composition, is the type of reactor used which in turn determines the temperature and heating rate. Tyre pyrolysis oil is chemically very complex containing aliphatic, aromatic, hetero-atom and polar fractions. The fuel characteristics of the tyre oil shows that it is similar to a gas oil or light fuel oil and has been successfully combusted in test furnaces and engines. The main gases produced from the pyrolysis of waste tyres are H{sub 2}, C{sub 1}–C{sub 4} hydrocarbons, CO{sub 2}, CO and H{sub 2}S. Upgrading tyre pyrolysis products to high value products has concentrated on char upgrading to higher quality carbon black and to activated carbon. The use of catalysts to upgrade the oil to a aromatic-rich chemical feedstock or the production of hydrogen from waste tyres has also been reported. Examples of commercial and semi-commercial scale tyre pyrolysis systems show that small scale batch reactors and continuous rotary kiln reactors have been developed to commercial scale.« less

Mass transfer effects in a gasification riser

DOE Office of Scientific and Technical Information (OSTI.GOV)

Breault, Ronald W.; Li, Tingwen; Nicoletti, Phillip

2013-07-01

In the development of multiphase reacting computational fluid dynamics (CFD) codes, a number of simplifications were incorporated into the codes and models. One of these simplifications was the use of a simplistic mass transfer correlation for the faster reactions and omission of mass transfer effects completely on the moderate speed and slow speed reactions such as those in a fluidized bed gasifier. Another problem that has propagated is that the mass transfer correlation used in the codes is not universal and is being used far from its developed bubbling fluidized bed regime when applied to circulating fluidized bed (CFB) risermore » reactors. These problems are true for the major CFD codes. To alleviate this problem, a mechanistic based mass transfer coefficient algorithm has been developed based upon an earlier work by Breault et al. This fundamental approach uses the local hydrodynamics to predict a local, time varying mass transfer coefficient. The predicted mass transfer coefficients and the corresponding Sherwood numbers agree well with literature data and are typically about an order of magnitude lower than the correlation noted above. The incorporation of the new mass transfer model gives the expected behavior for all the gasification reactions evaluated in the paper. At the expected and typical design values for the solid flow rate in a CFB riser gasifier an ANOVA analysis has shown the predictions from the new code to be significantly different from the original code predictions. The new algorithm should be used such that the conversions are not over predicted. Additionally, its behaviors with changes in solid flow rate are consistent with the changes in the hydrodynamics.« less

Prediction of Agglomeration, Fouling, and Corrosion Tendency of Fuels in CFB Co-Combustion

NASA Astrophysics Data System (ADS)

Barišć, Vesna; Zabetta, Edgardo Coda; Sarkki, Juha

Prediction of agglomeration, fouling, and corrosion tendency of fuels is essential to the design of any CFB boiler. During the years, tools have been successfully developed at Foster Wheeler to help with such predictions for the most commercial fuels. However, changes in fuel market and the ever-growing demand for co-combustion capabilities pose a continuous need for development. This paper presents results from recently upgraded models used at Foster Wheeler to predict agglomeration, fouling, and corrosion tendency of a variety of fuels and mixtures. The models, subject of this paper, are semi-empirical computer tools that combine the theoretical basics of agglomeration/fouling/corrosion phenomena with empirical correlations. Correlations are derived from Foster Wheeler's experience in fluidized beds, including nearly 10,000 fuel samples and over 1,000 tests in about 150 CFB units. In these models, fuels are evaluated based on their classification, their chemical and physical properties by standard analyses (proximate, ultimate, fuel ash composition, etc.;.) alongside with Foster Wheeler own characterization methods. Mixtures are then evaluated taking into account the component fuels. This paper presents the predictive capabilities of the agglomeration/fouling/corrosion probability models for selected fuels and mixtures fired in full-scale. The selected fuels include coals and different types of biomass. The models are capable to predict the behavior of most fuels and mixtures, but also offer possibilities for further improvements.

Novel dry-desulfurization process using Ca(OH)2/fly ash sorbent in a circulating fluidized bed.

PubMed

Matsushima, Norihiko; Li, Yan; Nishioka, Masateru; Sadakata, Masayoshi; Qi, Haiying; Xu, Xuchang

2004-12-15

A dry-desulfurization process using Ca(OH)2/fly ash sorbent and a circulating fluidized bed (CFB) was developed. Its aim was to achieve high SO2 removal efficiency without humidification and production of CaSO4 as the main byproduct. The CaSO4 produced could be used to treat alkalized soil. An 83% SO2 removal rate was demonstrated, and a byproduct with a high CaSO4 content was produced through baghouse ash. These results indicated that this process could remove SO2 in flue gas with a high efficiency under dry conditions and simultaneously produce soil amendment. It was shown that NO and NO2 enhanced the SO2 removal rate markedly and that NO2 increased the amount of CaSO4 in the final product more than NO. These results confirmed that the significant effects of NO and NO2 on the SO2 removal rate were due to chain reactions that occurred under favorable conditions. The amount of baghouse ash produced increased as the reaction progressed, indicating that discharge of unreacted Ca(OH)2 from the reactor was suppressed. Hence, unreacted Ca(OH)2 had a long residence time in the CFB, resulting in a high SO2 removal rate. It was also found that 350 degrees C is the optimum reaction temperature for dry desulfurization in the range tested (320-380 degrees C).

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nixon, J.D., E-mail: j.nixon@kingston.ac.uk; Wright, D.G.; Dey, P.K.

Highlights: • We evaluate operational municipal solid waste incinerators in the UK. • The supply chain of four case study plants are examined and compared in detail. • Technical, financial and operational data has been gathered for the four plants. • We suggest the best business practices for waste incinerators. • Appropriate strategy choices are the major difficulties for waste to energy plants. - Abstract: The uptake in Europe of Energy from Waste (EfW) incinerator plants has increased rapidly in recent years. In the UK, 25 municipal waste incinerators with energy recovery are now in operation; however, their waste supplymore » chains and business practices vary significantly. With over a hundred more plant developments being considered it is important to establish best business practices for ensuring efficient environmental and operational performance. By reviewing the 25 plants we identify four suitable case study plants to compare technologies (moving grate, fluidised bed and rotary kiln), plant economics and operations. Using data collected from annual reports and through interviews and site visits we provide recommendations for improving the supply chain for waste incinerators and highlight the current issues and challenges faced by the industry. We find that plants using moving grate have a high availability of 87–92%. However, compared to the fluidised bed and rotary kiln, quantities of bottom ash and emissions of hydrogen chloride and carbon monoxide are high. The uptake of integrated recycling practices, combined heat and power, and post incineration non-ferrous metal collections needs to be increased among EfW incinerators in the UK. We conclude that one of the major difficulties encountered by waste facilities is the appropriate selection of technology, capacity, site, waste suppliers and heat consumers. This study will be of particular value to EfW plant developers, government authorities and researchers working within the sector of waste management.« less

3D-Simulation Of Concentration Distributions Inside Large-Scale Circulating Fluidized Bed Combustors

NASA Astrophysics Data System (ADS)

Wischnewski, R.; Ratschow, L.; Hartge, E. U.; Werthe, J.

With increasing size of modern CFB combustors the lateral mixing of fuels and secondary air gains more and more importance. Strong concentration gradients, which result from improper lateral mixing, can lead to operational problems, high flue gas emissions and lower boiler efficiencies. A 3D-model for the simulation of local gas and solids concentrations inside industrial-sized CFB boilers has been developed. The model is based on a macroscopic approach and considers all major mechanisms during fuel spreading and subsequent combustion of char and volatiles. Typical characteristics of modern boilers like staged combustion, a smaller cross-sectional area in the lower section of the combustion chamber and the co-combustion of additional fuels with coal can be considered. The 252 MWth combustor of Stadtwerke Duisburg AG is used for the validation of the model. A comprehensive picture of the local conditions inside the combustion chamber is achieved by the combination of local gas measurements and the three-dimensional simulation of concentration distributions.

Jet penetration into a riser operated in dense suspension upflow: experimental and model comparisons

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shadle, L.J.; Ludlow, C.J.; Spenik, J.L.

2008-05-13

Solids tracers were used to characterize the penetration of a gas-solids jet directed toward the center of the 0.3-m diameter, circulating fluidized bed (CFB) riser. The penetration was measured by tracking phosphorescent particles illuminated immediately prior to injection into the riser. Photosensors and piezoelectric detectors were traversed across the radius of the riser at various axial positions to detect the phosphorescent jet material and particles traveling in the radial direction. Local particle velocities were measured at various radial positions, riser heights, and azimuthal angles using an optical fiber probe. Four (4) variables were tested including the jet velocity, solids feedmore » rate into the jet, the riser velocity, and overall CFB circulation rate over 8 distinct test cases with the central, or base case, repeated each time the test series was conducted. In addition to the experimental measurements made, the entire riser with a side feed jet of solids was simulated using the Eulerian-Eulerian computer model MFIX.« less

Characterization of Combustion and Emission of Several Kinds of Herbaceous Biomass Pellets in a Circulating Fluidized Bed Combustor

NASA Astrophysics Data System (ADS)

Li, S. Y.; Teng, H. P.; Jiao, W. H.; Shang, L. L.; Lu, Q. G.

Characterizations of combustion and emission of four kinds of herbaceous biomass pellets were investigated in a 0.15 MWt circulating fluidized bed. Corn stalk, wheat stalk, cotton stalk and king grass, which are typical herbaceous biomass in China, were chosen for this study. Temperature profile, emission in flue gas and agglomeration were studied by changing the combustion temperature between 750°C and 880°C. The combustion efficiencies are in the range from 97.4% to 99.4%, which are relatively high due to the homogeneous temperature profiles and good circulating fluidization of bed material. Suitable combustion temperatures for the different herbaceous biomass are mainly depended on the emission and bed agglomeration. SO2 and HCl concentrations in flue gas are in direct proportion to the sulfur and chlorine contents of the herbaceous biomass. Agglomeration at the cyclone leg and the loop seal is the main reason for defluidization in the CFB combustor.

ESTABLISHMENT OF AN ENVIRONMENTAL CONTROL TECHNOLOGY LABORATORY WITH A CIRCULATING FLUIDIZED-BED COMBUSTION SYSTEM

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wei-Ping Pan; Andy Wu; John T. Riley

This report is to present the progress made on the project ''Establishment of an Environmental Control Technology Laboratory (ECTL) with a Circulating Fluidized-Bed Combustion (CFBC) System'' during the period October 1, 2004 through December 31, 2004. The following tasks have been completed. First, the renovation of the new Combustion Laboratory and the construction of the Circulating Fluidized-Bed (CFB) Combustor Building have proceeded well. Second, the detailed design of supporting and hanging structures for the CFBC was completed. Third, the laboratory-scale simulated fluidized-bed facility was modified after completing a series of pretests. The two problems identified during the pretest were solved.more » Fourth, the carbonization of chicken waste and coal was investigated in a tube furnace and a Thermogravimetric Analyzer (TGA). The experimental results from this study are presented in this report. Finally, the proposed work for the next quarter has been outlined in this report.« less

Modeling biomass gasification in circulating fluidized beds

NASA Astrophysics Data System (ADS)

Miao, Qi

In this thesis, the modeling of biomass gasification in circulating fluidized beds was studied. The hydrodynamics of a circulating fluidized bed operating on biomass particles were first investigated, both experimentally and numerically. Then a comprehensive mathematical model was presented to predict the overall performance of a 1.2 MWe biomass gasification and power generation plant. A sensitivity analysis was conducted to test its response to several gasifier operating conditions. The model was validated using the experimental results obtained from the plant and two other circulating fluidized bed biomass gasifiers (CFBBGs). Finally, an ASPEN PLUS simulation model of biomass gasification was presented based on minimization of the Gibbs free energy of the reaction system at chemical equilibrium. Hydrodynamics plays a crucial role in defining the performance of gas-solid circulating fluidized beds (CFBs). A 2-dimensional mathematical model was developed considering the hydrodynamic behavior of CFB gasifiers. In the modeling, the CFB riser was divided into two regions: a dense region at the bottom and a dilute region at the top of the riser. Kunii and Levenspiel (1991)'s model was adopted to express the vertical solids distribution with some other assumptions. Radial distributions of bed voidage were taken into account in the upper zone by using Zhang et al. (1991)'s correlation. For model validation purposes, a cold model CFB was employed, in which sawdust was transported with air as the fluidizing agent. A comprehensive mathematical model was developed to predict the overall performance of a 1.2 MWe biomass gasification and power generation demonstration plant in China. Hydrodynamics as well as chemical reaction kinetics were considered. The fluidized bed riser was divided into two distinct sections: (a) a dense region at the bottom of the bed where biomass undergoes mainly heterogeneous reactions and (b) a dilute region at the top where most of homogeneous reactions occur in gas phase. Each section was divided into a number of small cells, over which mass and energy balances were applied. Due to the high heating rate in circulating fluidized bed, the pyrolysis was considered instantaneous. A number of homogeneous and heterogeneous reactions were considered in the model. Mass transfer resistance was considered negligible since the reactions were under kinetic control due to good gas-solid mixing. The model is capable of predicting the bed temperature distribution along the gasifier, the concentration and distribution of each species in the vertical direction of the bed, the composition and lower heating value (LHV) of produced gas, the gasification efficiency, the overall carbon conversion and the produced gas production rate. A sensitivity analysis was performed to test its response to several gasifier operating conditions. The model sensitivity analysis showed that equivalence ratio (ER), bed temperature, fluidization velocity, biomass feed rate and moisture content had various effects on the gasifier performance. However, the model was more sensitive to variations in ER and bed temperature. The model was validated using the experimental results obtained from the demonstration plant. The reactor was operated on rice husk at various ERs, fluidization velocities and biomass feed rates. The model gave reasonable predictions. The model was also validated by comparing the simulation results with two other different size CFBBGs using different biomass feedstock, and it was concluded that the developed model can be applied to other CFBBGs using various biomass fuels and having comparable reactor geometries. A thermodynamic model was developed under ASPEN PLUS environment. Using the approach of Gibbs free energy minimization, the model was essentially independent of kinetic parameters. A sensitivity analysis was performed on the model to test its response to operating variables, including ER and biomass moisture content. The results showed that the ER has the most effect on the product gas composition and LHV. The simulation results were compared with the experimental data obtained from the demonstration plant. Keywords: Biomass gasification; Mathematical model; Circulating fluidized bed; Hydrodynamics; Kinetics; Sensitivity analysis; Validation; Equivalence ratio; Temperature; Feed rate; Moisture; Syngas composition; Lower heating value; Gasification efficiency; Carbon conversion

Combustion and NOx emissions in deep-air-staging combustion of char in a circulating fluidized bed

NASA Astrophysics Data System (ADS)

Gong, Zhiqiang; Wang, Zhentong; Wang, Lei; Du, Aixun

2017-10-01

Combustion and NOx emissions in deep-air-staging (with higher level secondary air (SA) injection) combustion of char have been investigated in a CFB test rig. A good fluidized condition and uniform temperature distribution can be achieved with injection of higher level SA. NOx emission decreases with injection of higher level SA and the reduction effect is more obvious at higher temperature. NOx emission decreases with combustion temperature increasing for char combustion.

Extraction Techniques for Polycyclic Aromatic Hydrocarbons in Soils

PubMed Central

Lau, E. V.; Gan, S.; Ng, H. K.

2010-01-01

This paper aims to provide a review of the analytical extraction techniques for polycyclic aromatic hydrocarbons (PAHs) in soils. The extraction technologies described here include Soxhlet extraction, ultrasonic and mechanical agitation, accelerated solvent extraction, supercritical and subcritical fluid extraction, microwave-assisted extraction, solid phase extraction and microextraction, thermal desorption and flash pyrolysis, as well as fluidised-bed extraction. The influencing factors in the extraction of PAHs from soil such as temperature, type of solvent, soil moisture, and other soil characteristics are also discussed. The paper concludes with a review of the models used to describe the kinetics of PAH desorption from soils during solvent extraction. PMID:20396670

Improvement of CFD Methods for Modeling Full Scale Circulating Fluidized Bed Combustion Systems

NASA Astrophysics Data System (ADS)

Shah, Srujal; Klajny, Marcin; Myöhänen, Kari; Hyppänen, Timo

With the currently available methods of computational fluid dynamics (CFD), the task of simulating full scale circulating fluidized bed combustors is very challenging. In order to simulate the complex fluidization process, the size of calculation cells should be small and the calculation should be transient with small time step size. For full scale systems, these requirements lead to very large meshes and very long calculation times, so that the simulation in practice is difficult. This study investigates the requirements of cell size and the time step size for accurate simulations, and the filtering effects caused by coarser mesh and longer time step. A modeling study of a full scale CFB furnace is presented and the model results are compared with experimental data.

Full-scale results for TAM limestone injection

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baer, S.

1996-12-31

Information is outlined on the use of thermally active marble (TAM) sorbents in boilers. Data are presented on: the comparison of TAM to limestone; NOVACON process development history; CFB test history; CFB pilot scale test; full-scale CFB trial; August, 1996 CFB demonstration; Foster Wheeler Mount Carmel sorbent feed rate comparison and Ca:S comparison; unburned carbon is ash; and advantages and savings in CFB boilers.

The simulation of influence of different coals on the circulating fluidized bed Boiler's combustion performance

NASA Astrophysics Data System (ADS)

Yong, Yumei; Lu, Qinggang

2003-05-01

The combustion performance of the boiler largely depends on the coal type. Lots of experimental research shows that different fuels have different combustion characteristics. It is obvious that fuel will change the whole operating performance of Circulating Fluidized Bed Combustion (CFBC). We know even in a pilot-scale running boiler, the measurement of some parameters is difficult and costly. Therefore, we developed the way of simulation to evaluate the combustion performance of Chinese coals in CFB. The simulation results show that, different coals will result in different coal particle diameter and comminution depending on their mineral component and the change will affect the distribution of ash in CFBC system. In a word, the computational results are in accordance with experimental results qualitatively but there are some differences quantitatively.

Foil bearings

NASA Astrophysics Data System (ADS)

Elrod, David A.

1993-11-01

The rolling element bearings (REB's) which support many turbomachinery rotors offer high load capacity, low power requirements, and durability. Two disadvantages of REB's are: (1) rolling or sliding contact within the bearing has life-limiting consequences; and (2) REB's provide essentially no damping. The REB's in the Space Shuttle Main Engine (SSME) turbopumps must sustain high static and dynamic loads, at high speeds, with a cryogenic fluid as lubricant and coolant. The pump end ball bearings limit the life of the SSME high pressure oxygen turbopump (HPOTP). Compliant foil bearing (CFB) manufacturers have proposed replacing turbopump REB's with CFB's CFB's work well in aircraft air cycle machines, auxiliary power units, and refrigeration compressors. In a CFB, the rotor only contracts the foil support structure during start up and shut down. CFB damping is higher than REB damping. However, the load capacity of the CFB is low, compared to a REB. Furthermore, little stiffness and damping data exists for the CFB. A rotordynamic analysis for turbomachinery critical speeds and stability requires the input of bearing stiffness and damping coefficients. The two basic types of CFB are the tension-dominated bearing and the bending-dominated bearing. Many investigators have analyzed and measured characteristics of tension-dominated foil bearings, which are applied principally in magnetic tape recording. The bending-dominated CFB is used more in rotating machinery. This report describes the first phase of a structural analysis of a bending-dominated, multileaf CFB. A brief discussion of CFB literature is followed by a description and results of the present analysis.

Environmental hazard of oil shale combustion fly ash.

PubMed

Blinova, Irina; Bityukova, Liidia; Kasemets, Kaja; Ivask, Angela; Käkinen, Aleksandr; Kurvet, Imbi; Bondarenko, Olesja; Kanarbik, Liina; Sihtmäe, Mariliis; Aruoja, Villem; Schvede, Hedi; Kahru, Anne

2012-08-30

The combined chemical and ecotoxicological characterization of oil shale combustion fly ash was performed. Ash was sampled from the most distant point of the ash-separation systems of the Balti and Eesti Thermal Power Plants in North-Eastern Estonia. The fly ash proved potentially hazardous for tested aquatic organisms and high alkalinity of the leachates (pH>10) is apparently the key factor determining its toxicity. The leachates were not genotoxic in the Ames assay. Also, the analysis showed that despite long-term intensive oil-shale combustion accompanied by considerable fly ash emissions has not led to significant soil contamination by hazardous trace elements in North-Eastern Estonia. Comparative study of the fly ash originating from the 'new' circulating fluidized bed (CFB) combustion technology and the 'old' pulverized-fired (PF) one showed that CFB fly ash was less toxic than PF fly ash. Thus, complete transfer to the 'new' technology will reduce (i) atmospheric emission of hazardous trace elements and (ii) fly ash toxicity to aquatic organisms as compared with the 'old' technology. Copyright © 2012 Elsevier B.V. All rights reserved.

Broadband UV spectroscopy system used for monitoring of SO 2 and NO emissions from thermal power plants

NASA Astrophysics Data System (ADS)

Zhang, Y. G.; Wang, H. S.; Somesfalean, G.; Wang, Z. Y.; Lou, X. T.; Wu, S. H.; Zhang, Z. G.; Qin, Y. K.

2010-11-01

A gas monitoring system based on broadband absorption spectroscopic techniques in the ultraviolet region is described and tested. The system was employed in real-time continuous concentration measurements of sulfur dioxide (SO 2) and nitric oxide (NO) from a 220-ton h -1 circulating fluidized bed (CFB) boiler in Shandong province, China. The emission coefficients (per kg of coal and per kWh of electricity) and the total emission of the two pollutant gases were evaluated. The measurement results showed that the emission concentrations of SO 2 and NO from the CFB boiler fluctuated in the range of 750-1300 mg m -3 and 100-220 mg m -3, respectively. Compared with the specified emission standards of air pollutants from thermal power plants in China, the values were generally higher for SO 2 and lower for NO. The relatively high emission concentrations of SO 2 were found to mainly depend on the sulfur content of the fuel and the poor desulfurization efficiency. This study indicates that the broadband UV spectroscopy system is suitable for industrial emission monitoring and pollution control.

Foster Wheeler's Solutions for Large Scale CFB Boiler Technology: Features and Operational Performance of Łagisza 460 MWe CFB Boiler

NASA Astrophysics Data System (ADS)

Hotta, Arto

During recent years, once-through supercritical (OTSC) CFB technology has been developed, enabling the CFB technology to proceed to medium-scale (500 MWe) utility projects such as Łagisza Power Plant in Poland owned by Poludniowy Koncern Energetyczny SA. (PKE), with net efficiency nearly 44%. Łagisza power plant is currently under commissioning and has reached full load operation in March 2009. The initial operation shows very good performance and confirms, that the CFB process has no problems with the scaling up to this size. Also the once-through steam cycle utilizing Siemens' vertical tube Benson technology has performed as predicted in the CFB process. Foster Wheeler has developed the CFB design further up to 800 MWe with net efficiency of ≥45%.

Self-organizing sensing and actuation for automatic control

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cheng, George Shu-Xing

A Self-Organizing Process Control Architecture is introduced with a Sensing Layer, Control Layer, Actuation Layer, Process Layer, as well as Self-Organizing Sensors (SOS) and Self-Organizing Actuators (SOA). A Self-Organizing Sensor for a process variable with one or multiple input variables is disclosed. An artificial neural network (ANN) based dynamic modeling mechanism as part of the Self-Organizing Sensor is described. As a case example, a Self-Organizing Soft-Sensor for CFB Boiler Bed Height is presented. Also provided is a method to develop a Self-Organizing Sensor.

Thermomechanical CSM analysis of a superheater tube in transient state

NASA Astrophysics Data System (ADS)

Taler, Dawid; Madejski, Paweł

2011-12-01

The paper presents a thermomechanical computational solid mechanics analysis (CSM) of a pipe "double omega", used in the steam superheaters in circulating fluidized bed (CFB) boilers. The complex cross-section shape of the "double omega" tubes requires more precise analysis in order to prevent from failure as a result of the excessive temperature and thermal stresses. The results have been obtained using the finite volume method for transient state of superheater. The calculation was carried out for the section of pipe made of low-alloy steel.

Validation of material point method for soil fluidisation analysis

NASA Astrophysics Data System (ADS)

Bolognin, Marco; Martinelli, Mario; Bakker, Klaas J.; Jonkman, Sebastiaan N.

2017-06-01

The main aim of this paper is to describe and analyse the modelling of vertical column tests that undergo fluidisation by the application of a hydraulic gradient. A recent advancement of the material point method (MPM), allows studying both stationary and non-stationary fluid flow while interacting with the solid phase. The fluidisation initiation and post-fluidisation processes of the soil will be investigated with an advanced MPM formulation (Double Point) in which the behavior of the solid and the liquid phase is evaluated separately, assigning to each of them a set of material points (MPs). The result of these simulations are compared to analytic solutions and measurements from laboratory experiments. This work is used as a benchmark test for the MPM double point formulation in the Anura3D software and to verify the feasibility of the software for possible future engineering applications.

Analysis of CFB, a cytokinin-responsive gene of Arabidopsis thaliana encoding a novel F-box protein regulating sterol biosynthesis.

PubMed

Brenner, Wolfram G; Leuendorf, Jan Erik; Cortleven, Anne; Martin, Laetitia B B; Schaller, Hubert; Schmülling, Thomas

2017-05-17

Protein degradation by the ubiquitin-26S proteasome pathway is important for the regulation of cellular processes, but the function of most F-box proteins relevant to substrate recognition is unknown. We describe the analysis of the gene Cytokinin-induced F-box encoding (CFB, AT3G44326), identified in a meta-analysis of cytokinin-related transcriptome studies as one of the most robust cytokinin response genes. F-box domain-dependent interaction with the E3 ubiquitin ligase complex component ASK1 classifies CFB as a functional F-box protein. Apart from F-box and transmembrane domains, CFB contains no known functional domains. CFB is expressed in all plant tissues, predominantly in root tissue. A ProCFB:GFP-GUS fusion gene showed strongest expression in the lateral root cap and during lateral root formation. CFB-GFP fusion proteins were mainly localized in the nucleus and the cytosol but also at the plasma membrane. cfb mutants had no discernible phenotype, but CFB overexpressing plants showed several defects, such as a white upper inflorescence stem, similar to the hypomorphic cycloartenol synthase mutant cas1-1. Both CFB overexpressing plants and cas1-1 mutants accumulated the CAS1 substrate 2,3-oxidosqualene in the white stem tissue, the latter even more after cytokinin treatment, indicating impairment of CAS1 function. This suggests that CFB may link cytokinin and the sterol biosynthesis pathway. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Effect of filter media size, mass flow rate and filtration stage number in a moving-bed granular filter on the yield and properties of bio-oil from fast pyrolysis of biomass.

PubMed

Paenpong, Chaturong; Inthidech, Sudsakorn; Pattiya, Adisak

2013-07-01

Fast pyrolysis of cassava rhizome was performed in a bench-scale fluidised-bed reactor unit incorporated with a cross-flow moving-bed granular filter. The objective of this research was to examine several process parameters including the granular size (425-1160 μm) and mass flow rate (0-12 g/min) as well as the number of the filtration stages (1-2 stages) on yields and properties of bio-oil. The results showed that the bio-oil yield decreased from 57.7 wt.% to 42.0-49.2 wt.% when increasing the filter media size, the mass flow rate and the filtration stage number. The effect of the process parameters on various properties of bio-oil is thoroughly discussed. In general, the bio-oil quality in terms of the solids content, ash content, initial viscosity, viscosity change and ageing rate could be enhanced by the hot vapour granular filtration. Therefore, bio-oil of high stability could be produced by the pyrolysis reactor configuration designed in this work. Copyright © 2013 Elsevier Ltd. All rights reserved.

Magneto-optical properties of CoFeB ultrathin films: Effect of Ta buffer and capping layer

NASA Astrophysics Data System (ADS)

Husain, Sajid; Gupta, Nanhe Kumar; Barwal, Vineet; Chaudhary, Sujeet

2018-05-01

The effect of adding Ta as a capping and buffer layer on ultrathin CFB(Co60Fe20B20) thin films has been investigated by magneto-optical Kerr effect. A large difference in the coercivity and saturation field is observed between the single layer CFB(2nm) and Ta(5nm)/CFB(2nm)/Ta(2nm) trilayer structure. In particular, the in-plane anisotropy energy is found to be 90kJ/m3 on CFB(2nm) and 2.22kJ/m3 for Ta(5nm)/CFB(2nm)/Ta(2nm) thin films. Anisotropy energy further reduced to 0.93kJ/m3 on increasing the CFB thinness in trilayer structure i.e., Ta(5nm)/CFB(4nm)/Ta(2nm). Using VSM measurement, the saturation magnetization is found to be 1230±50 kA/m. Low coercivity and anisotropy energy in capped and buffer layer thin films envisage the potential of employing CFB for low field switching applications of the spintronic devices.

Flow Regime Study in a High Density Circulating Fluidized Bed Riser with an Abrupt Exit

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mei, J.S.; Shadle, L.J.; Yue, P.C.

2007-01-01

Flow regime study was conducted in a 0.3 m diameter, 15.5 m height circulating fluidized bed (CFB) riser with an abrupt exit at the National Energy Technology Laboratory of the U.S. Department of Energy. Local particle velocities were measured at various radial positions and riser heights using an optical fiber probe. On-line measurement of solid circulating rate was continuously recorded by the Spiral. Glass beads of mean diameter 61 μm and particle density of 2,500 kg/m3 were used as bed material. The CFB riser was operated at various superficial gas velocities ranging from 3 to 7.6 m/s and solid massmore » flux from 20 to 550 kg/m2-s. At a constant riser gas velocity, transition from fast fluidization to dense suspension upflow (DSU) regime started at the bottom of the riser with increasing solid flux. Except at comparatively low riser gas velocity and solid flux, the apparent solid holdup at the top exit region was higher than the middle section of the riser. The solid fraction at this top region could be much higher than 7% under high riser gas velocity and solid mass flux. The local particle velocity showed downward flow near the wall at the top of the riser due to its abrupt exit. This abrupt geometry reflected the solids and, therefore, caused solid particles traveling downward along the wall. However, at location below, but near, the top of the riser the local particle velocities were observed flowing upward at the wall. Therefore, DSU was identified in the upper region of the riser with an abrupt exit while the fully developed region, lower in the riser, was still exhibiting core-annular flow structure. Our data were compared with the flow regime boundaries proposed by Kim et al. [1] for distinguishing the dilute pneumatic transport, fast fluidization, and DSU.« less

Basic design studies for a 600 MWe CFB boiler (270b, 2 x 600 C)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bursi, J.M.; Lafanechere, L.; Jestin, L.

Commercial CFB boilers are currently available in the 300 MWe equivalent range for use with international coal. Retrofitting of Provence 4 with a 250 MWe CFB boiler was an important step in CFB development. In light of the results obtained from two large French units--Emile Huchet 4 (125 MWe) and Provence 4 (250 MWe)--this paper focuses on the main technical points which are currently being studied in relation to the basic design of a 600 MWe CFB boiler, a project that has been undertaken by EDF. The general aim of this project is to demonstrate the competitiveness of a CFBmore » boiler compared with a PF boiler. The main areas of focus in the design of this large CFB boiler with advanced steam conditions are described. These points are subjected to particular analysis from a design standpoint. The objective is to prepare the precise specifications needed to ensure a product which is optimized in terms of quality/cost or service/cost. Due to the present lack of theoretical understanding of the refined and complex two-phase flow, design is a challenge which has to be based on reliable and comprehensive data obtained from large plants in commercial operation. This will ensure that the advantages of CFB which arise from the hydrodynamics within the circulation loop are maintained. The major goals of maintaining good particle residence time and concentration in the furnace are described. Misunderstanding of CFB furnace bottom conditions is also pointed out, with cost reduction and better NO{sub x} capture certainly among the major new targets in relation to bottom furnace design. General problems associated with the heat exchanger arrangement, principally those linked to high steam conditions and, especially, the vaporization system, are discussed. Once again, comparison with PF in this area showed that CFB boilers appear more competitive. Finally, the main area in which there is a need for sharing of CFB experience among CFB users is pointed out.« less

Simulation of hydrodynamics using large eddy simulation-second-order moment model in circulating fluidized beds

NASA Astrophysics Data System (ADS)

Juhui, Chen; Yanjia, Tang; Dan, Li; Pengfei, Xu; Huilin, Lu

2013-07-01

Flow behavior of gas and particles is predicted by the large eddy simulation of gas-second order moment of solid model (LES-SOM model) in the simulation of flow behavior in CFB. This study shows that the simulated solid volume fractions along height using a two-dimensional model are in agreement with experiments. The velocity, volume fraction and second-order moments of particles are computed. The second-order moments of clusters are calculated. The solid volume fraction, velocity and second order moments are compared at the three different model constants.

An approach for modeling thermal destruction of hazardous wastes in circulating fluidized bed incinerator.

PubMed

Patil, M P; Sonolikar, R L

2008-10-01

This paper presents a detailed computational fluid dynamics (CFD) based approach for modeling thermal destruction of hazardous wastes in a circulating fluidized bed (CFB) incinerator. The model is based on Eular - Lagrangian approach in which gas phase (continuous phase) is treated in a Eularian reference frame, whereas the waste particulate (dispersed phase) is treated in a Lagrangian reference frame. The reaction chemistry hasbeen modeled through a mixture fraction/ PDF approach. The conservation equations for mass, momentum, energy, mixture fraction and other closure equations have been solved using a general purpose CFD code FLUENT4.5. Afinite volume method on a structured grid has been used for solution of governing equations. The model provides detailed information on the hydrodynamics (gas velocity, particulate trajectories), gas composition (CO, CO2, O2) and temperature inside the riser. The model also allows different operating scenarios to be examined in an efficient manner.

Characteristics of Pyrolytic Topping in Fluidized Bed for Different Volatile Coals

NASA Astrophysics Data System (ADS)

Xiong, R.; Dong, L.; Xu, G. W.

Coal is generally combusted or gasified directly to destroy completely the chemical structures, such as aromatic rings containing in volatile coals including bituminite and lignite. Coal topping refers to a process that extracts chemicals with aromatic rings from such volatile coals in advance of combustion or gasification and thereby takes advantage of the value of coal as a kind of chemical structure resource. CFB boiler is the coal utilization facility that can be easily retrofitted to implement coal topping. A critical issue for performing coal topping is the choice of the pyrolytic reactor that can be different types. The present study concerns fluidized bed reactor that has rarely been tested for use in coal topping. Two different types of coals, one being Xiaolongtan (XLT) lignite and the other Shanxi (SX) bituminous, were tested to clarify the yield and composition of pyrolysis liquid and gas under conditions simulating actual operations. The results showed that XLT lignite coals had the maximum tar yield in 823-873K and SX bituminite realized its highest tar yield in 873-923K. Overall, lignite produced lower tar yield than bituminous coal. The pyrolysis gas from lignite coals contained more CO and CO2 and less CH4, H2 and C2+C3 (C2H4, C2H6, C3H6, C3H8) components comparing to that from bituminous coal. TG-FTIR analysis of tars demonstrated that for different coals there are different amounts of typical chemical species. Using coal ash of CFB boiler, instead of quartz sand, as the fluidized particles decreased the yields of both tar and gas for all the tested coals. Besides, pyrolysis in a reaction atmosphere simulating the pyrolysis gas (instead of N2) resulted also in higher production of pyrolysis liquid.

Assessment of elemental mobility in soil using a fluidised bed approach with on-line ICP-MS analysis.

PubMed

Beeston, Michael Philip; Glass, Hylke Jan; van Elteren, Johannes Teun; Slejkovec, Zdenka

2007-09-19

A new method has been developed to analyse the mobility of elements within soils employing counter-current flow soil contacting in a fluidised bed (FB) column. This method alleviates the problem of irreproducible peaks suffered by state-of-the-art micro-column techniques as a result of particle compaction. Reproducible extraction profiles are produced through the leaching of soil with a linear gradient of 0.05 mol L(-1) ammonium sulphate to 0.11 mol L(-1) acetic acid using a high pressure liquid chromatography (HPLC) quaternary pump, and the continuous monitoring of the elements in the leachate with inductively coupled plasma mass spectrometry (ICP-MS). Quantification of the procedure is achieved with an external flow injection (FI) calibration method. Flow rate and FB column length were investigated as critical parameters to the efficiency of the extraction methodology. It was found that an increase in the column length from 10 to 20 cm using a flow rate of 0.15 mL min(-1) produced the same increase in extracted elemental concentration as an increase in flow rate from 0.15 to 0.30 mL min(-1). In both examples, the increase in the concentration of elements leached from the soil may be ascribed to the increase in the concentration gradient between the solid and liquid. The exhaustive nature of the technique defines the maximum leachable concentration within the operationally defined leaching parameters of the exchangeable phase, providing a more accurate assessment of the risk associated with the elements in the soil for the phase providing the greatest risk to the environment. The multi-elemental high sensitivity nature of the on-line detector provides an accurate determination of the associations present between the elements in the soil, and the identification of multiple phases within the exchangeable phase through the presence of multiple peaks in the extraction profiles. It is possible through the deconvolution of these extraction profiles that the concentration corresponding to the peaks identified can be defined.

Numerical Simulation in a Supercirtical CFB Boiler

NASA Astrophysics Data System (ADS)

Zhang, Yanjun; Gaol, Xiang; Luo, Zhongyang; Jiang, Xiaoguo

The dimension of the hot circulation loop of the supercritical CFB boiler is large, and there are many unknowns and challenges that should be identified and resolved during the development. In order to realize a reasonable and reliable design of the hot circulation loop, numerical simulation of gas-solid flow in a supercritical CFB boiler was conducted by using FLUENT software. The working condition of hot circulation loop flow field, gas-solid flow affected by three unsymmetrical cyclones, air distribution and pressure drop in furnace were analyzed. The simulation results showed that the general arrangement of the 600MWe supercritical CFB boiler is reasonable.

Emission and distribution of PCDD/Fs, chlorobenzenes, chlorophenols, and PAHs from stack gas of a fluidized bed and a stoker waste incinerator in China.

PubMed

Wang, Tianjiao; Chen, Tong; Lin, Xiaoqing; Zhan, Mingxiu; Li, Xiaodong

2017-02-01

The concentrations, homologue, and congener profiles, as well as the gas/particle distribution of polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), chlorobenzenes (CBzs), chlorophenols (CPhs), and polyaromatic hydrocarbons (PAHs) from stack gas of two different municipal solid waste incinerators in China, were characterized. The incinerators were a stoker furnace incinerator equipped with the advanced air pollution control device (APCD) and a common circulating fluidized bed (CFB) furnace. The concentration of PCDD/Fs in the stack gas of the stoker incinerator ranged 0.011-0.109 ng international toxic equivalent factor (I-TEQ)/Nm 3 and was below the current limit for PCDD/F emissions from the municipal solid waste incinerators (MSWIs) in China (0.1 ng I-TEQ/Nm 3 ) in most of the cases. Moreover, the concentration of PCDD/Fs in the stack gas of the stoker incinerator was significantly lower than that of the CFB incinerator (0.734 to 24.6 ng I-TEQ/Nm 3 ). In both incinerators, the majority of the total PCDD/F emissions (above 90%) ended up in the gas phase. 2,3,4,7,8-PeCDF, which occupied 24.3-43.6 and 32.5-75.6% of I-TEQ contribution in MSWIs A and B, respectively, was the most abundant congener. However, different types of incinerators and APCDs induced different congener and homologue distributions. The total concentration of CBzs from the stoker incinerator (0.05-3.2 μg/Nm 3 ) was also much lower than that formed from the CFB incinerator (10.9-75.2 μg/Nm 3 ). The phase distribution of CBzs followed the same pattern as with the PCDD/Fs. Moreover, the emission level of CBz was 100-1000 times higher than that of the PCDD/Fs, which determines the applicability of CBzs as indicators of PCDD/F emissions. High correlations between the emission concentrations of PCDD/Fs, TeCBz, and PCBz in specific ranges were revealed. Furthermore, high concentrations of CPhs (0.6-141.0 μg/Nm 3 ) and PAHs (148.6-4986.5 μg/Nm 3 ) were detected in the stack gases of MSWI B. In some cases, the concentrations were as high as the concentrations in the fumes exiting the boiler of one foreign stoker without flue gas purification indicating the abundance of CPh and PAH emissions in the stack gas of waste incinerators.

Origin of the Mackenzie large igneous province and sourcing of flood basalts from layered intrusions

NASA Astrophysics Data System (ADS)

Day, J. M.; Pearson, D.

2013-12-01

The 1.27 Ga Coppermine continental flood basalt (CFB) in northern Canada represents the extrusive manifestation of the Mackenzie large igneous province (LIP) that includes the Mackenzie dyke swarm and the Muskox layered intrusion. New Re-Os isotope and highly siderophile element (HSE: Re, Pd, Pt, Ru, Ir, Os) abundance data are reported together with whole-rock major- and trace-element abundances and Nd isotopes to examine the behaviour of the HSE during magmatic differentiation and to place constraints on the extent of crustal interaction with mantle-derived melts. Mineral-chemical data are also reported for an unusual andesite glass flow (4.9 wt.% MgO) found in proximity to newly recognised picrites (>20 wt.% MgO) in the lowermost stratigraphy of the Coppermine CFB. Compositions of mineral phases in the andesite are similar to equivalent phases found in Muskox Intrusion chromitites and the melt composition is identical to Muskox chromite melt inclusions. Elevated HSE contents (e.g., 3.8 ppb Os) and the mantle-like initial Os isotope composition of this andesitic glass contrast strongly with oxygen isotope and lithophile element evidence for extensive crustal contamination. These signatures implicate an origin for the glass as a magma mingling product formed within the Muskox Intrusion during chromitite genesis. The combination of crust and mantle signatures define roles for both these reservoirs in chromitite genesis, but the HSE appear to be dominantly mantle-sourced. Combined with Nd isotope data that places the feeder for lower Coppermine CFB picrites and basalts within the Muskox Intrusion, this provides the strongest evidence yet for direct processing of some CFB within upper-crustal magma chambers. Modeling of absolute and relative HSE abundances in CFB reveal that HSE concentrations decrease with increasing fractionation for melts with <8×1 wt.% MgO in the Coppermine CFB, with picrites (>13.5wt.% MgO) from CFB having higher Os abundances than ocean island basalt (OIB) equivalents. The differences between CFB and OIB picrite absolute Os abundances may result from higher degrees of partial melting to form CFB but may also reflect incorporation of trace sulphide in CFB picrites from magmas that reached S-saturation in shallow-level magma chambers. Significant inter-element fractionation between (Re+Pt+Pd)/(Os+Ir+Ru) are generated during magmatic differentiation in response to strongly contrasting partitioning of these two groups of elements into sulphides and/or HSE-rich alloys. Furthermore, fractional crystallization has a greater role on absolute and relative HSE abundances than crustal contamination under conditions of CFB petrogenesis due to the dilution effect of continental crust. The Coppermine CFB define a Re-Os isochron with an age of 1263 +16/-20 Ma and initial gamma Os = +2.2×0.8. Combined data for the basaltic and intrusive portions of the Mackenzie LIP indicate a mantle source broadly within the range of the primitive upper mantle. The majority of Archaean komatiites and Phanerozoic CFB also require mantle sources with primitive upper mantle to chondritic Re/Os evolution, with exceptions typically being from analyses of highly-fractionated MgO-poor basalts.

FlexTech{trademark}

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wilhelm, B.

1996-12-31

Information is presented on a 110 MWe atmospheric CFB located in the Czech Republic firing brown coal. The following topics are discussed: fuel analysis; boiler design parameters; CFB fluidizing nozzle; and project time schedule. Information is also given on a 200 MWe atmospheric CFB located in the Republic of Korea firing Korean anthracite. Data are presented on fuel specifications; predicted performance; and engineering and construction schedule.

A study on the Jordanian oil shale resources and utilization

NASA Astrophysics Data System (ADS)

Sakhrieh, Ahmad; Hamdan, Mohammed

2012-11-01

Jordan has significant oil shale deposits occurring in 26 known localities. Geological surveys indicate that the existing deposits underlie more than 60% of Jordan's territory. The resource consists of 40 to 70 billion tones of oil shale, which may be equivalent to more than 5 million tones of shale oil. Since the 1960s, Jordan has been investigating economical and environmental methods for utilizing oil shale. Due to its high organic content, is considered a suitable source of energy. This paper introduces a circulating fluidized bed combustor that simulates the behavior of full scale municipal oil shale combustors. The inside diameter of the combustor is 500 mm, the height is 3000 mm. The design of the CFB is presented. The main parameters which affect the combustion process are elucidated in the paper. The size of the laboratory scale fluidized bed reactor is 3 kW, which corresponds to a fuel-feeding rate of approximately 1.5 kg/h.

Evaluation of AFBC co-firing of coal and hospital wastes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1991-02-01

The purpose of this program is to expand the use of coal by utilizing CFB (circulating fluidized bed) technology to provide an environmentally safe method for disposing of waste materials. Hospitals are currently experiencing a waste management crisis. In many instances, they are no longer permitted to burn pathological and infectious wastes in incinerators. Older hospital incinerators are not capable of maintaining the stable temperatures and residence times necessary in order to completely destroy toxic substances before release into the atmosphere. In addition, the number of available landfills which can safely handle these substances is decreasing each year. The purposemore » of this project is to conduct necessary research investigating whether the combustion of the hospital wastes in a coal-fired circulating fluidized bed boiler will effectively destroy dioxins and other hazardous substances before release into the atmosphere. If this is proven feasible, in light of the quantity of hospital wastes generated each year, it would create a new market for coal -- possibly 50 million tons/year.« less

Characterization of three antifungal calcite-forming bacteria, Arthrobacter nicotianae KNUC2100, Bacillus thuringiensis KNUC2103, and Stenotrophomonas maltophilia KNUC2106, derived from the Korean islands, Dokdo and their application on mortar.

PubMed

Park, Jong-Myong; Park, Sung-Jin; Ghim, Sa-Youl

2013-09-28

Crack remediation on the surface of cement mortar using microbiological calcium carbonate (CaCO3) precipitation (MICP) has been investigated as a microbial sealing agent on construction materials. However, MICP research has never acknowledged the antifungal properties of calcite-forming bacteria (CFB). Since fungal colonization on concrete surfaces can trigger biodeterioration processes, fungi on concrete buildings have to be prevented. Therefore, to develop a microbial sealing agent that has antifungal properties to remediate cement cracks without deteriorative fungal colonization, we introduced an antifungal CFB isolated from oceanic islands (Dokdo islands, territory of South Korea, located at the edge of the East Sea in Korea.). The isolation of CFB was done using B4 or urea-CaCl2 media. Furthermore, antifungal assays were done using the pairing culture and disk diffusion methods. Five isolated CFB showed CaCO3 precipitation and antifungal activities against deteriorative fungal strains. Subsequently, five candidate bacteria were identified using 16S rDNA sequence analysis. Crack remediation, fungi growth inhibition, and water permeability reduction of antifungal CFB-treated cement surfaces were tested. All antifungal CFB showed crack remediation abilities, but only three strains (KNUC2100, 2103, and 2106) reduced the water permeability. Furthermore, these three strains showed fungi growth inhibition. This paper is the first application research of CFB that have antifungal activity, for an eco-friendly improvement of construction materials.

Influence of a glass wool hot vapour filter on yields and properties of bio-oil derived from rapid pyrolysis of paddy residues.

PubMed

Pattiya, Adisak; Suttibak, Suntorn

2012-07-01

This article reports experimental results of rapid or fast pyrolysis of rice straw (RS) and rice husk (RH) in a fluidised-bed reactor unit incorporated with a hot vapour filter. The objective of this research was to investigate the effects of pyrolysis temperatures and the use of glass wool hot vapour filtration on pyrolysis products. The results showed that the optimum pyrolysis temperatures for RS and RH were 405 and 452 °C, which gave maximum bio-oil yields of 54.1 and 57.1 wt.% on dry biomass basis, respectively. The use of the hot filter led to a reduction of 4-7 wt.% bio-oil yield. Nevertheless, the glass wool hot filtered bio-oils appeared to have better quality in terms of initial viscosity, solids content and ash content than the non-filtered ones. Copyright © 2012 Elsevier Ltd. All rights reserved.

Semicontinuous production of ethanol from agricultural wastes by immobilised coculture in a two stage bioreactor.

PubMed

Dey, Sabita

2002-10-01

The seed testing laboratories of Maharashtra discard 10 tonnes of grains and oil seeds treated with pesticides per annum. These agricultural wastes could be converted to reducing sugar and ethanol in a two stage semicontinuous fluidised bed bioreactor containing immobilised, Bacillus sp. and Zymomonas mobilis in the 1st stage and Saccharomyces diastaticus and S. cerevisae in the 2nd stage. The optimum temperature and pH for fermentation in both the stages were 30 degrees C and 7.2 respectively. In this process 600 g (approximately 400 g starch) waste seeds could yield 402 g of reducing sugar in the 1st stage after 20 h and 205 g ethanol in the 2nd stage after 40 h incubation with a yield factor 0.51. Using these system 10 tonnes of agricultural wastes could be converted to 3.4 x 107 g of ethanol.

Production of a nitrogeneous humic fertilizer by the oxidation-ammoniation of lignite

DOE Office of Scientific and Technical Information (OSTI.GOV)

Coca, J.

1984-12-01

Two lignite samples were oxidised with HNO/sub 3/ (20% wt) at 75 C and treated afterwards with NH/sub 3/ in a fluidised-bed reactor in a temperature range 100-375 C. The effects of temperature, NH/sub 3/ flow rate, and reaction time on the total N/sub 2/ content of the product are reported. The product contained 7-13% wt of total N/sub 2/ which increased as the ammoniation temperature increased. Soil nitrification measurements of the N/sub 2/-enriched lignites showed that the maximum conversion to nitrates and rate of nitrification are exhibited by the product obtained at the lowest ammoniation temperature, i.e. 100 C.more » Maximum conversion to nitrates at that temperature was 45%, which compares well with similar products such as ammoniated peat (35%) and ammonium nitrohumates (45%).« less

Earth's evolving subcontinental lithospheric mantle: inferences from LIP continental flood basalt geochemistry

NASA Astrophysics Data System (ADS)

Greenough, John D.; McDivitt, Jordan A.

2018-04-01

Archean and Proterozoic subcontinental lithospheric mantle (SLM) is compared using 83 similarly incompatible element ratios (SIER; minimally affected by % melting or differentiation, e.g., Rb/Ba, Nb/Pb, Ti/Y) for >3700 basalts from ten continental flood basalt (CFB) provinces representing nine large igneous provinces (LIPs). Nine transition metals (TM; Fe, Mn, Sc, V, Cr, Co, Ni, Cu, Zn) in 102 primitive basalts (Mg# = 0.69-0.72) from nine provinces yield additional SLM information. An iterative evaluation of SIER values indicates that, regardless of age, CFB transecting Archean lithosphere are enriched in Rb, K, Pb, Th and heavy REE(?); whereas P, Ti, Nb, Ta and light REE(?) are higher in Proterozoic-and-younger SLM sources. This suggests efficient transfer of alkali metals and Pb to the continental lithosphere perhaps in association with melting of subducted ocean floor to form Archean tonalite-trondhjemite-granodiorite terranes. Titanium, Nb and Ta were not efficiently transferred, perhaps due to the stabilization of oxide phases (e.g., rutile or ilmenite) in down-going Archean slabs. CFB transecting Archean lithosphere have EM1-like SIER that are more extreme than seen in oceanic island basalts (OIB) suggesting an Archean SLM origin for OIB-enriched mantle 1 (EM1). In contrast, OIB high U/Pb (HIMU) sources have more extreme SIER than seen in CFB provinces. HIMU may represent subduction-processed ocean floor recycled directly to the convecting mantle, but to avoid convective homogenization and produce its unique Pb isotopic signature may require long-term isolation and incubation in SLM. Based on all TM, CFB transecting Proterozoic lithosphere are distinct from those cutting Archean lithosphere. There is a tendency for lower Sc, Cr, Ni and Cu, and higher Zn, in the sources for Archean-cutting CFB and EM1 OIB, than Proterozoic-cutting CFB and HIMU OIB. All CFB have SiO2 (pressure proxy)-Nb/Y (% melting proxy) relationships supporting low pressure, high % melting resembling OIB tholeiites, but TM concentrations do not correlate with % melting. Thus, the association of layered intrusion (plutonic CFB) TM deposits with Archean terranes does not appear related to higher metal concentrations or higher percentages of melting in Archean SLM. Other characteristics of these EM1-like magmas (e.g., S2 or O2 fugacity) may lead to element scavenging and concentration during differentiation to form ore deposits.

Study on the flow in the pipelines of the support system of circulating fluidized bed

NASA Astrophysics Data System (ADS)

Meng, L.; Yang, J.; Zhou, L. J.; Wang, Z. W.; Zhuang, X. H.

2013-12-01

In the support system of Circulating Fluidized Bed (Below referred to as CFB) of thermal power plant, the pipelines of primary wind are used for transporting the cold air to the boiler, which is important in controlling and combustion effect. The pipeline design will greatly affect the energy loss of the system, and accordingly affect the thermal power plant economic benefits and production environment. Three-dimensional numerical simulation is carried out for the pipeline internal flow field of a thermal power plant in this paper. Firstly three turbulence models were compared and the results showed that the SST k-ω model converged better and the energy losses predicted were closer to the experimental results. The influence of the pipeline design form on the flow characteristics are analysed, then the optimization designs of the pipeline are proposed according to the energy loss distribution of the flow field, in order to reduce energy loss and improve the efficiency of tunnel. The optimization plan turned out to be efficacious; about 36% of the pressure loss is reduced.

Evaluation of AFBC co-firing of coal and hospital wastes. Technical report, January 1989--August 1990

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1991-02-01

The purpose of this program is to expand the use of coal by utilizing CFB (circulating fluidized bed) technology to provide an environmentally safe method for disposing of waste materials. Hospitals are currently experiencing a waste management crisis. In many instances, they are no longer permitted to burn pathological and infectious wastes in incinerators. Older hospital incinerators are not capable of maintaining the stable temperatures and residence times necessary in order to completely destroy toxic substances before release into the atmosphere. In addition, the number of available landfills which can safely handle these substances is decreasing each year. The purposemore » of this project is to conduct necessary research investigating whether the combustion of the hospital wastes in a coal-fired circulating fluidized bed boiler will effectively destroy dioxins and other hazardous substances before release into the atmosphere. If this is proven feasible, in light of the quantity of hospital wastes generated each year, it would create a new market for coal -- possibly 50 million tons/year.« less

Enzyme immobilisation in biocatalysis: why, what and how.

PubMed

Sheldon, Roger A; van Pelt, Sander

2013-08-07

In this tutorial review, an overview of the why, what and how of enzyme immobilisation for use in biocatalysis is presented. The importance of biocatalysis in the context of green and sustainable chemicals manufacture is discussed and the necessity for immobilisation of enzymes as a key enabling technology for practical and commercial viability is emphasised. The underlying reasons for immobilisation are the need to improve the stability and recyclability of the biocatalyst compared to the free enzyme. The lower risk of product contamination with enzyme residues and low or no allergenicity are further advantages of immobilised enzymes. Methods for immobilisation are divided into three categories: adsorption on a carrier (support), encapsulation in a carrier, and cross-linking (carrier-free). General considerations regarding immobilisation, regardless of the method used, are immobilisation yield, immobilisation efficiency, activity recovery, enzyme loading (wt% in the biocatalyst) and the physical properties, e.g. particle size and density, hydrophobicity and mechanical robustness of the immobilisate, i.e. the immobilised enzyme as a whole (enzyme + support). The choice of immobilisate is also strongly dependent on the reactor configuration used, e.g. stirred tank, fixed bed, fluidised bed, and the mode of downstream processing. Emphasis is placed on relatively recent developments, such as the use of novel supports such as mesoporous silicas, hydrogels, and smart polymers, and cross-linked enzyme aggregates (CLEAs).

Retrospective study

PubMed Central

Lu, Chao; Lv, Xueyou; Lin, Yiming; Li, Dejian; Chen, Lihua; Ji, Feng; Li, Youming; Yu, Chaohui

2016-01-01

Abstract Conventional forceps biopsy (CFB) is the most popular way to screen for gastric epithelial neoplasia (GEN) and adenocarcinoma of gastric epithelium. The aim of this study was to compare the diagnostic accuracy between conventional forceps biopsy and endoscopic submucosal dissection (ESD). Four hundred forty-four patients who finally undertook ESD in our hospital were enrolled from Jan 1, 2009 to Sep 1, 2015. We retrospectively assessed the characteristics of pathological results of CFB and ESD. The concordance rate between CFB and ESD specimens was 68.92% (306/444). Men showed a lower concordance rate (63.61% vs 79.33%; P = 0.001) and concordance patients were younger (P = 0.048). In multivariate analysis, men significantly had a lower concordance rate (coefficient −0.730, P = 0.002) and a higher rate of pathological upgrade (coefficient −0.648, P = 0.015). Locations of CFB did not influence the concordance rate statistically. The concordance rate was relatively high in our hospital. According to our analysis, old men plus gastric fundus or antrum of CFB were strongly suggested to perform ESD if precancerous lesions were found. And young women with low-grade intraepithelial neoplasia could select regular follow-up. PMID:27472723

Suppressing effect of saikosaponin A, an active ingredient of Bupleurum falcatum, on chocolate self-administration and reinstatement of chocolate seeking in rats.

PubMed

Lorrai, Irene; Maccioni, Paola; Carai, Mauro A M; Capra, Alessandro; Castelli, M Paola; Riva, Antonella; Morazzoni, Paolo; Gessa, Gian Luigi; Colombo, Giancarlo

2017-01-18

Recent lines of experimental evidence have indicated that saikosaponin A (SSA) - a bioactive ingredient of the medicinal plant, Bupleurum falcatum L. - suppressed alcohol, morphine, and cocaine self-administration in rats. The present paper was designed to assess whether the protective properties of SSA on addiction-related behaviors generalize to a hyperpalatable food such as a chocolate-flavored beverage (CFB). To this end, rats were initially trained to lever-respond for CFB [5% (w/v) Nesquik ® powder in water] under fixed ratio (FR) 10 (FR10) schedule of reinforcement. Once lever-responding reached stable levels, rats were treated acutely with two different dose ranges of SSA (0, 0.25, 0.5, and 1mg/kg; 0, 1, 2.5, and 5mg/kg; i.p.) and exposed to the FR10 and progressive ratio (PR) schedules of reinforcement in four independent experiments. The effect of acutely administered SSA (0, 0.25, 0.5, and 1mg/kg; i.p.) on cue-induced reinstatement of seeking behavior for CFB was also assessed. Under the FR and PR schedules of reinforcement, treatment with SSA diminished lever-responding for CFB, amount of self-administered CFB, and breakpoint for CFB. All variables were virtually completely suppressed after treatment with 5mg/kg SSA. Treatment with SSA also suppressed reinstatement of CFB-seeking behavior. No dose of SSA altered rat motor-performance, evaluated exposing all rats to an inverted screen test immediately after the self-administration session. These results demonstrate that acute treatment with SSA potently suppressed several addictive-like behaviors motivated by highly hedonic nourishment. These data extend to a highly rewarding natural stimulus the anti-addictive properties of SSA recently disclosed in rats self-administering alcohol, morphine, and cocaine. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Impact of crop field burning and mountains on heavy haze in the North China Plain: a case study

NASA Astrophysics Data System (ADS)

Long, Xin; Tie, Xuexi; Cao, Junji; Huang, Rujin; Feng, Tian; Li, Nan; Zhao, Suyu; Tian, Jie; Li, Guohui; Zhang, Qiang

2016-08-01

With the provincial statistical data and crop field burning (CFB) activities captured by Moderate Resolution Imaging Spectroradiometer (MODIS), we extracted a detailed CFB emission inventory in the North China Plain (NCP). The WRF-CHEM model was applied to investigate the impact of CFB on air pollution during the period from 6 to 12 October 2014, corresponding to a heavy haze incident with high concentrations of PM2.5 (particulate matter with aerodynamic diameter less than 2.5 µm). The WRF-CHEM model generally performed well in simulating the surface species concentrations of PM2.5, O3 and NO2 compared to the observations; in addition, it reasonably reproduced the observed temporal variations of wind speed, wind direction and planetary boundary layer height (PBLH). It was found that the CFB that occurred in southern NCP (SNCP) had a significant effect on PM2.5 concentrations locally, causing a maximum of 34 % PM2.5 increase. Under continuous southerly wind conditions, the CFB pollution plume went through a long-range transport to northern NCP (NNCP; with several mega cities, including Beijing, the capital city of China), where few CFBs occurred, resulting in a maximum of 32 % PM2.5 increase. As a result, the heavy haze in Beijing was enhanced by the CFB, which occurred in SNCP. Mountains also play significant roles in enhancing the PM2.5 pollution in NNCP through the blocking effect. The mountains blocked and redirected the airflows, causing the pollutant accumulations along the foothills of mountains. This study suggests that the prohibition of CFB should be strict not only in or around Beijing, but also on the ulterior crop growth areas of SNCP. PM2.5 emissions in SNCP should be significantly limited in order to reduce the occurrences of heavy haze events in the NNCP region.

Obseration of flow regime transition in CFB riser using an LDV

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yue, Paul C.; Mei, Joseph S.; Shadle, Lawrence J.

2011-01-01

The solids flow in a circulating fluidized bed (CFB) riser is often described to have a core-annular structure. For a given superficial gas velocity, at the initial introduction of solids into a riser a flow structure of dilute upflow regime exists. Continuing to increase the solids flow in the riser transitions the flow structure to the core-annular flow regime. However, with further increase of solids flow a condition is reached, depending on the superficial gas velocity, where all the solids across the riser cross section flow upwards, even those at the wall. When the solids flux, solids fraction and gasmore » velocity are relatively high, such a condition is described as the dense phase suspense upflow (DSU) regime. In this paper we report our observations of these flow regime transitions by using a laser Doppler velocimeter (LDV) to monitor the upward and downward particle flow velocities at and near the riser wall of the National Energy Technology Laboratory’s 30.4 centimeters diameter CFB cold flow model. The particles were high density polyethylene (PPE) spheres with a Sauter mean diameter of 861 micron and a density of 800 kg/m3. Three superficial gas velocities of 6.55 m/s, 10.67 m/s and 13.72 m/s were used in this study. For the case of superficial gas velocity 6.55 m/s, the experimental data show that the transition from dilute upflow to core-annular flow occurred when the solids flux was about 7 kg/m{sup 2}-s and the transition from core-annular flow to dense suspension upflow was about 147 kg/m{sup 2}-s. As the superficial gas velocity was increased to 10.67 m/s the corresponding flow regime transitions were at 34 kg/m{sup 2}-s and 205 kg/m{sup 2}-s, respectively. For the case of superficial gas velocity of 13.72 m/s the data showed no distinct transition of flow regimes. The particles were all upflow for the range of solids fluxes from 10 kg/m{sup 2}-s to 286 kg/m{sup 2}-s.« less

Effects of clofibrate and indocyanine green on the hepatobiliary disposition of acetaminophen and its metabolites in male CD-1 mice.

PubMed

Chen, C; Hennig, G E; McCann, D J; Manautou, J E

2000-11-01

1. The effects of clofibrate (CFB) and indocyanine green (ICG) on the biliary excretion of acetaminophen (APAP) and its metabolites were investigated. 2. Male CD-1 mice were pretreated with 500 mg CFB/kg, i.p. for 10 days. Controls received corn oil vehicle only. After overnight fasting, common bile duct-cannulated mice were challenged with a non-toxic dose of APAP (1 mmol/kg, i.v.). 3. CFB pretreatment did not affect bile flow rate, nor did it affect the cumulative biliary excretion of APAP and its conjugated metabolites. 4. Additional CFB or corn oil pretreated mice were given 30 mumol indocyanine green (ICG)/kg, i.v., immediately before APAP dosing. ICG is a non-metabolizable organic anion that is completely excreted into the bile through a canalicular transport process for organic anions. 5. ICG significantly decreased the bile flow rate and biliary concentration of APAP-glutathione, APAP-glucuronide and APAP-mercapturate within the first hour after dosing without affecting the biliary concentration of APAP. 6. The results indicate that CFB pretreatment does not affect the total amount of APAP and its metabolites excreted in bile. They also suggest that the biliary excretion of several conjugated metabolites of APAP share the same excretory pathway with the organic anion ICG.

Biscuits with No Added Sugar Containing Stevia, Coffee Fibre and Fructooligosaccharides Modifies α-Glucosidase Activity and the Release of GLP-1 from HuTu-80 Cells and Serotonin from Caco-2 Cells after In Vitro Digestion

PubMed Central

Martinez-Saez, Nuria; Hochkogler, Christina Maria; Somoza, Veronika; del Castillo, Maria Dolores

2017-01-01

This study assessed the in vitro effects of the bioaccessible food components released during the simulated human digestion of a coffee fibre-containing biscuit (CFB) on α-glucosidase activity, antioxidant capacity and satiety hormones. Digest of CFB presented a significantly (p < 0.05) lower amount of sugar (68.6 mg/g) and a higher antioxidant capacity (15.1 mg chlorogenic acid eq./g) than that of a sucrose-containing biscuit (SCB). The CFB significantly reduced (p < 0.05) α-glucosidase activity (IC50 = 3.3 mg/mL) compared to the SCB (IC50 = 6.2 mg/mL). Serotonin and glucagon-like peptide-1 (GLP-1) release by differentiated Caco-2 and HuTu-80 cells, respectively, was stimulated by the CFB (355% at a concentration of 0.5 mg/mL and 278% at a concentration of 0.05 mg/mL) to the same order of magnitude as those of the SCB. To summarize, the CFB was demonstrated to reduce monosaccharide bioaccessibility, to inhibit a diabetes-related digestive enzyme, and to improve the release of satiety hormones. PMID:28677657

Biscuits with No Added Sugar Containing Stevia, Coffee Fibre and Fructooligosaccharides Modifies α-Glucosidase Activity and the Release of GLP-1 from HuTu-80 Cells and Serotonin from Caco-2 Cells after In Vitro Digestion.

PubMed

Martinez-Saez, Nuria; Hochkogler, Christina Maria; Somoza, Veronika; Del Castillo, Maria Dolores

2017-07-04

This study assessed the in vitro effects of the bioaccessible food components released during the simulated human digestion of a coffee fibre-containing biscuit (CFB) on α-glucosidase activity, antioxidant capacity and satiety hormones. Digest of CFB presented a significantly ( p < 0.05) lower amount of sugar (68.6 mg/g) and a higher antioxidant capacity (15.1 mg chlorogenic acid eq./g) than that of a sucrose-containing biscuit (SCB). The CFB significantly reduced ( p < 0.05) α-glucosidase activity (IC50 = 3.3 mg/mL) compared to the SCB (IC50 = 6.2 mg/mL). Serotonin and glucagon-like peptide-1 (GLP-1) release by differentiated Caco-2 and HuTu-80 cells, respectively, was stimulated by the CFB (355% at a concentration of 0.5 mg/mL and 278% at a concentration of 0.05 mg/mL) to the same order of magnitude as those of the SCB. To summarize, the CFB was demonstrated to reduce monosaccharide bioaccessibility, to inhibit a diabetes-related digestive enzyme, and to improve the release of satiety hormones.

Retrospective study: The diagnostic accuracy of conventional forceps biopsy of gastric epithelial compared to endoscopic submucosal dissection (STROBE compliant).

PubMed

Lu, Chao; Lv, Xueyou; Lin, Yiming; Li, Dejian; Chen, Lihua; Ji, Feng; Li, Youming; Yu, Chaohui

2016-07-01

Conventional forceps biopsy (CFB) is the most popular way to screen for gastric epithelial neoplasia (GEN) and adenocarcinoma of gastric epithelium. The aim of this study was to compare the diagnostic accuracy between conventional forceps biopsy and endoscopic submucosal dissection (ESD).Four hundred forty-four patients who finally undertook ESD in our hospital were enrolled from Jan 1, 2009 to Sep 1, 2015. We retrospectively assessed the characteristics of pathological results of CFB and ESD.The concordance rate between CFB and ESD specimens was 68.92% (306/444). Men showed a lower concordance rate (63.61% vs 79.33%; P = 0.001) and concordance patients were younger (P = 0.048). In multivariate analysis, men significantly had a lower concordance rate (coefficient -0.730, P = 0.002) and a higher rate of pathological upgrade (coefficient -0.648, P = 0.015). Locations of CFB did not influence the concordance rate statistically.The concordance rate was relatively high in our hospital. According to our analysis, old men plus gastric fundus or antrum of CFB were strongly suggested to perform ESD if precancerous lesions were found. And young women with low-grade intraepithelial neoplasia could select regular follow-up.

Controlled-frequency breath swimming improves swimming performance and running economy.

PubMed

Lavin, K M; Guenette, J A; Smoliga, J M; Zavorsky, G S

2015-02-01

Respiratory muscle fatigue can negatively impact athletic performance, but swimming has beneficial effects on the respiratory system and may reduce susceptibility to fatigue. Limiting breath frequency during swimming further stresses the respiratory system through hypercapnia and mechanical loading and may lead to appreciable improvements in respiratory muscle strength. This study assessed the effects of controlled-frequency breath (CFB) swimming on pulmonary function. Eighteen subjects (10 men), average (standard deviation) age 25 (6) years, body mass index 24.4 (3.7) kg/m(2), underwent baseline testing to assess pulmonary function, running economy, aerobic capacity, and swimming performance. Subjects were then randomized to either CFB or stroke-matched (SM) condition. Subjects completed 12 training sessions, in which CFB subjects took two breaths per length and SM subjects took seven. Post-training, maximum expiratory pressure improved by 11% (15) for all 18 subjects (P < 0.05) while maximum inspiratory pressure was unchanged. Running economy improved by 6 (9)% in CFB following training (P < 0.05). Forced vital capacity increased by 4% (4) in SM (P < 0.05) and was unchanged in CFB. These findings suggest that limiting breath frequency during swimming may improve muscular oxygen utilization during terrestrial exercise in novice swimmers. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Health-related quality of life, cognitive screening, and functional status in a randomized phase III trial (EF-14) of tumor treating fields with temozolomide compared to temozolomide alone in newly diagnosed glioblastoma.

PubMed

Zhu, Jay-Jiguang; Demireva, Petya; Kanner, Andrew A; Pannullo, Susan; Mehdorn, Maximilian; Avgeropoulos, Nicholas; Salmaggi, Andrea; Silvani, Antonio; Goldlust, Samuel; David, Carlos; Benouaich-Amiel, Alexandra

2017-12-01

We characterized health-related quality of life (HRQoL), cognitive, and functional status in newly diagnosed glioblastoma (GBM) patients receiving Tumor treating fields (TTFields) with temozolomide (TMZ) versus TMZ alone in a planned interim analysis of a randomized phase III trial [NCT00916409], which showed significant improvement in progression-free and overall survival with TTFields/TMZ. After radiotherapy with concomitant TMZ, newly diagnosed GBM patients were randomized (2:1) to TTFields/TMZ (n = 210) or TMZ (n = 105). Interim analysis was performed in 315 patients with ≥18 months of follow-up. HRQoL, a secondary endpoint, was evaluated in per-protocol patient population and expressed as change from baseline (CFB) at 3, 6, and 9 months for each subscale in the EORTC QLQ-C30/BN20. Karnofsky performance scores (KPS) and Mini-Mental State Examination scores (MMSE) were assessed. CFB in HRQoL was balanced in treatment groups at the 12-month time point. Initially, HRQoL improved in patients treated with TTFields/TMZ (CFB3: 24% and CFB6: 13%) versus TMZ (CFB3: -7% and CFB6: -17%), though this difference was no longer evident at the 9-month point. General scales, including physical and social functioning, showed no difference at 9 and 12 months. TTFields/TMZ group reported higher concerns of "itchy skin". KPS over 12 months was just below 90 in both groups. Cognitive status (MMSE) was stable over time. HRQoL, KPS, and MMSE were balanced in both groups over time. There was no preliminary evidence that HRQoL, cognitive, and functional status is adversely affected by the continuous use of TTFields.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Potter, N; Lebron, S; Yan, G

Purpose: Various dosimetric benefits such as increased dose rate, and reduced leakage and out of field dose has led to the growth of FFF technology in the clinic. In this study, we concentrate on investigating the feasibility of using flattening-filter-free (FFF) beams to deliver conventional flat beams (CFB), since completely getting rid of the flattening-filter module from the gantry head can not only simplify the gantry design but also decrease the workload on machine maintain and quality assurance. Methods: The sliding window based IMRT technique was utilized to generate the CFB from the FFF beam for various beam configurations onmore » the Elekta Versa HD. The flat beam reproducibility and MU efficiency were compared for each beam configuration among FFF planning, delivery and CFB planning. Results: Compared to the CFB plan, the 3%3mm passing rates of the FFF beams from both measurement and plan are 100% and 95%(or better) for 15×15 cm{sup 2} or smaller field size and for any field size greater than 15×15 cm{sup 2}at 10 cm depth, respectively. The largest discrepancy is about 5% and typically appears at the field shoulder area. The MU increase average was 80% for FFF compared to CFB, however has a minimal impact on treatment delivery time. Conclusion: The ability to deliver conventional flat treatments is not absent when operating in FFF mode. With proper TPS manipulation and beam modulation, FFF mode can achieve reasonable flat profiles and comparable dose coverage as CFB does for various conventional treatment techniques, such as four field box, or long spine treatment techniques. The ability to deliver most clinical treatments from the same treatment unit, will allow for less quality assurance as well as maintenance, and completely eliminate the need for the flattening filter on modern linacs.« less

Low temperature circulating fluidized bed gasification and co-gasification of municipal sewage sludge. Part 1: Process performance and gas product characterization.

PubMed

Thomsen, Tobias Pape; Sárossy, Zsuzsa; Gøbel, Benny; Stoholm, Peder; Ahrenfeldt, Jesper; Frandsen, Flemming Jappe; Henriksen, Ulrik Birk

2017-08-01

Results from five experimental campaigns with Low Temperature Circulating Fluidized Bed (LT-CFB) gasification of straw and/or municipal sewage sludge (MSS) from three different Danish municipal waste water treatment plants in pilot and demonstration scale are analyzed and compared. The gasification process is characterized with respect to process stability, process performance and gas product characteristics. All experimental campaigns were conducted at maximum temperatures below 750°C, with air equivalence ratios around 0.12 and with pure silica sand as start-up bed material. A total of 8600kg of MSS dry matter was gasified during 133h of operation. The average thermal loads during the five experiments were 62-100% of nominal capacity. The short term stability of all campaigns was excellent, but gasification of dry MSS lead to substantial accumulation of coarse and rigid, but un-sintered, ash particles in the system. Co-gasification of MSS with sufficient amounts of cereal straw was found to be an effective way to mitigate these issues as well as eliminate thermal MSS drying requirements. Characterization of gas products and process performance showed that even though gas composition varied substantially, hot gas efficiencies of around 90% could be achieved for all MSS fuel types. Copyright © 2017 Elsevier Ltd. All rights reserved.

CAPE-OPEN simulation of waste-to-energy technologies for urban cities

NASA Astrophysics Data System (ADS)

Andreadou, Christina; Martinopoulos, Georgios

2018-01-01

Uncontrolled waste disposal and unsustainable waste management not only damage the environment, but also affect human health. In most urban areas, municipal solid waste production is constantly increasing following the everlasting increase in energy consumption. Technologies aim to exploit wastes in order to recover energy, decrease the depletion rate of fossil fuels, and reduce waste disposal. In this paper, the annual amount of municipal solid waste disposed in the greater metropolitan area of Thessaloniki is taken into consideration, in order to size and model a combined heat and power facility for energy recovery. From the various waste-to-energy technologies available, a fluidised bed combustion boiler combined heat and power plant was selected and modelled through the use of COCO, a CAPE-OPEN simulation software, to estimate the amount of electrical and thermal energy that could be generated for different boiler pressures. Although average efficiency was similar in all cases, providing almost 15% of Thessaloniki's energy needs, a great variation in the electricity to thermal energy ratio was observed.

Power generation based on biomass by combined fermentation and gasification--a new concept derived from experiments and modelling.

PubMed

Methling, Torsten; Armbrust, Nina; Haitz, Thilo; Speidel, Michael; Poboss, Norman; Braun-Unkhoff, Marina; Dieter, Heiko; Kempter-Regel, Brigitte; Kraaij, Gerard; Schliessmann, Ursula; Sterr, Yasemin; Wörner, Antje; Hirth, Thomas; Riedel, Uwe; Scheffknecht, Günter

2014-10-01

A new concept is proposed for combined fermentation (two-stage high-load fermenter) and gasification (two-stage fluidised bed gasifier with CO2 separation) of sewage sludge and wood, and the subsequent utilisation of the biogenic gases in a hybrid power plant, consisting of a solid oxide fuel cell and a gas turbine. The development and optimisation of the important processes of the new concept (fermentation, gasification, utilisation) are reported in detail. For the gas production, process parameters were experimentally and numerically investigated to achieve high conversion rates of biomass. For the product gas utilisation, important combustion properties (laminar flame speed, ignition delay time) were analysed numerically to evaluate machinery operation (reliability, emissions). Furthermore, the coupling of the processes was numerically analysed and optimised by means of integration of heat and mass flows. The high, simulated electrical efficiency of 42% including the conversion of raw biomass is promising for future power generation by biomass. Copyright © 2014 Elsevier Ltd. All rights reserved.

Temporal mismatch between induction of superoxide dismutase and ascorbate peroxidase correlates with high H2O2 concentration in seawater from clofibrate-treated red algae Kappaphycus alvarezii.

PubMed

Barros, Marcelo P; Granbom, Malena; Colepicolo, Pio; Pedersén, Marianne

2003-12-01

Algal cells have developed different strategies to cope with the common environmentally promoted generation of H(2)O(2), which include induction of catalase (CAT) and ascorbate peroxidase (APX), massive H(2)O(2) release in seawater, and synthesis of volatile halocarbons by specific peroxidases. The antioxidant adaptability of the economically important carrageenophyte Kappaphycus alvarezii (Doty) Doty (Gigartinales: Rhodophyta) was tested here against exposure to clofibrate (CFB), a known promoter of peroxisomal beta-oxidation in mammals and plants. Possibly as a consequence of CFB-induced H2O2 peroxisomal production, the maximum concentration of H(2)O(2) in the seawater of red algae cultures was found to occur (120+/-17 min) after the addition of CFB, which was followed by a significant decrease in the photosynthetic activity of PSII after 24 h. Interestingly, 4 h after the addition of CFB, the total SOD activity was about 2.5-fold higher than in the control, whereas no significant changes were observed in lipoperoxidation levels (TBARS) or in CAT and APX activities. The two H(2)O(2)-scavenging enzymes were only induced later (after 72 h), whereupon CAT showed a dose-dependent response with increasing concentrations of CFB. A more pronounced increase of TBARS concentration than in the controls was evidenced when a 50 microM Fe(2+/3+) solution (3:2 ratio) was added to CFB-treated cultures, suggesting that the combination of exacerbated H(2)O(2) levels in the seawater-in this work, caused by CFB exposure-and Fenton-reaction catalyst (ferric/ferrous ions), imposes harsh oxidative conditions on algal cultures. The bulk of data suggests that K. alvarezii possesses little ability to promptly induce CAT and APX compared to the immediately responsive antioxidant enzyme SOD and, to avoid harmful accumulation of H(2)O(2), the red alga presumably releases H(2)O(2) into the surrounding medium as an alternative mechanism.

Gasification of algal biomass (Cladophora glomerata L.) with CO2/H2O/O2 in a circulating fluidized bed.

PubMed

Ebadi, Abdol Ghaffar; Hisoriev, Hikmat

2017-11-28

Gasification is one of the most important thermochemical routes to produce both synthesis gas (syngas) and chars. The quality of produced syngas wieldy depends on the operating conditions (temperature, residence time, heating rate, and gasifying agent), hydrodynamic properties of gasifier (particle size, minimum fluidization velocity, and gasifier size), and type of feedstock (coal, biomass, oil, and municipal solid wastes). In the present study, simulation of syngas production via circulating fluidized bed (CFB) gasification of algal biomass (Cladophora glomerata L.) at different gasifying agents and particle sizes was carried out, using Aspen Plus simulator. The model which has been validated by using experimental data of the technical literature was used to evaluate the influence of operating conditions on gas composition and performance parameters. The results show that biomass gasification using pure oxygen as the gasification agent has great potential to improve the caloric value of produced gas and performance indicators. It was also found that the produced gas caloric value, syngas yield, and performance parameters (CCE and CGE) increase with reaction temperature but are inversely proportional to the biomass particle size.

Alkali activation of recovered fuel-biofuel fly ash from fluidised-bed combustion: Stabilisation/solidification of heavy metals.

PubMed

Yliniemi, Juho; Pesonen, Janne; Tiainen, Minna; Illikainen, Mirja

2015-09-01

Recovered fuel-biofuel fly ash from a fluidized bed boiler was alkali-activated and granulated with a sodium-silicate solution in order to immobilise the heavy metals it contains. The effect of blast-furnace slag and metakaolin as co-binders were studied. Leaching standard EN 12457-3 was applied to evaluate the immobilisation potential. The results showed that Ba, Pb and Zn were effectively immobilised. However, there was increased leaching after alkali activation for As, Cu, Mo, Sb and V. The co-binders had minimal or even negative effect on the immobilisation. One exception was found for Cr, in which the slag decreased leaching, and one was found for Cu, in which the slag increased leaching. A sequential leaching procedure was utilized to gain a deeper understanding of the immobilisation mechanism. By using a sequential leaching procedure it is possible fractionate elements into watersoluble, acid-soluble, easily-reduced and oxidisable fractions, yielding a total 'bioavailable' amount that is potentially hazardous for the environment. It was found that the total bioavailable amount was lower following alkali activation for all heavy metals, although the water-soluble fraction was higher for some metals. Evidence from leaching tests suggests the immobilisation mechanism was chemical retention, or trapping inside the alkali activation reaction products, rather than physical retention, adsorption or precipitation as hydroxides. Copyright © 2015 Elsevier Ltd. All rights reserved.

Gas-phase and particle-phase PCDD/F congener distributions in the flue gas from an iron ore sintering plant.

PubMed

Liu, Xiaolong; Ye, Meng; Wang, Xue; Liu, Wen; Zhu, Tingyu

2017-04-01

The activated carbon injection-circulating fluidized bed (ACI-CFB)-bag filter coupling technique was studied in an iron ore sintering plant. For comparison, the removal efficiencies under the conditions without or with ACI technology were both evaluated. It was found that the polychlorinated dibenzo-p-dioxins and dibenzofuran (PCDD/F) removal efficiency for total international toxic equivalence quantity (I-TEQ) concentration was improved from 91.61% to 97.36% when ACI was employed, revealing that ACI was very conducive to further controlling the PCDD/F emissions. Detailed congener distributions of PCDD/Fs in the gas-phase and particle-phase of the Inlet and Outlet samples were determined. Additionally, the PCDD/F distribution for the Fly ash-with ACI sample of was also studied. Copyright © 2016. Published by Elsevier B.V.

Studies in Three Phase Gas-Liquid Fluidised Systems

NASA Astrophysics Data System (ADS)

Awofisayo, Joyce Ololade

1992-01-01

Available from UMI in association with The British Library. The work is a logical continuation of research started at Aston some years ago when studies were conducted on fermentations in bubble columns. The present work highlights typical design and operating problems that could arise in such systems as waste water, chemical, biochemical and petroleum operations involving three-phase, gas-liquid -solid fluidisation; such systems are in increasing use. It is believed that this is one of few studies concerned with "true" three-phase, gas-liquid-solid fluidised systems, and that this work will contribute significantly to closing some of the gaps in knowledge in this area. The research work was experimentally based and involved studies of the hydrodynamic parameters, phase holdups (gas and solid), particle mixing and segregation, and phase flow dynamics (flow regime and circulation patterns). The studies have focused particularly on the solid behaviour and the influence of properties of solids present on the above parameters in three-phase, gas-liquid-solid fluidised systems containing single particle components and those containing binary and ternary mixtures of particles. All particles were near spherical in shape and two particle sizes and total concentration levels were used. Experiments were carried out in two- and three-dimensional bubble columns. Quantitative results are presented in graphical form and are supported by qualitative results from visual studies which are also shown as schematic diagrams and in photographic form. Gas and solid holdup results are compared for air-water containing single, binary and ternary component particle mixtures. It should be noted that the criteria for selection of the materials used are very important if true three-phase fluidisation is to be achieved: this is very evident when comparing the results with those in the literature. The fluid flow and circulation patterns observed were assessed for validation of the generally accepted patterns, and the author believes that the present work provides more accurate insight into the modelling of liquid circulation in bubble columns. The characteristic bubbly flow at low gas velocity in a two-phase system is suppressed in the three-phase system. The degree of mixing within the system is found to be dependent on flow regime, liquid circulation and the ratio of solid phase physical properties.

CONCEPTUAL DESIGN AND ECONOMICS OF THE ADVANCED CO2 HYBRID POWER CYCLE

DOE Office of Scientific and Technical Information (OSTI.GOV)

A. Nehrozoglu

2004-12-01

Research has been conducted under United States Department of Energy Contract DEFC26-02NT41621 to analyze the feasibility of a new type of coal-fired plant for electric power generation. This new type of plant, called the Advanced CO{sub 2} Hybrid Power Plant, offers the promise of efficiencies nearing 36 percent, while concentrating CO{sub 2} for 100% sequestration. Other pollutants, such as SO{sub 2} and NOx, are sequestered along with the CO{sub 2} yielding a zero emissions coal plant. The CO{sub 2} Hybrid is a gas turbine-steam turbine combined cycle plant that uses CO{sub 2} as its working fluid to facilitate carbon sequestration. The key components of the plant are a cryogenic air separation unit (ASU), a pressurized circulating fluidized bed gasifier, a CO{sub 2} powered gas turbine, a circulating fluidized bed boiler, and a super-critical pressure steam turbine. The gasifier generates a syngas that fuels the gas turbine and a char residue that, together with coal, fuels a CFB boiler to power the supercritical pressure steam turbine. Both the gasifier and the CFB boiler use a mix of ASU oxygen and recycled boiler flue gas as their oxidant. The resulting CFB boiler flue gas is essentially a mixture of oxygen, carbon dioxide and water. Cooling the CFB flue gas to 80 deg. F condenses most of the moisture and leaves a CO{sub 2} rich stream containing 3%v oxygen. Approximately 30% of this flue gas stream is further cooled, dried, and compressed for pipeline transport to the sequestration site (the small amount of oxygen in this stream is released and recycled to the system when the CO{sub 2} is condensed after final compression and cooling). The remaining 70% of the flue gas stream is mixed with oxygen from the ASU and is ducted to the gas turbine compressor inlet. As a result, the gas turbine compresses a mixture of carbon dioxide (ca. 64%v) and oxygen (ca. 32.5%v) rather than air. This carbon dioxide rich mixture then becomes the gas turbine working fluid and also becomes the oxidant in the gasification and combustion processes. As a result, the plant provides CO{sub 2} for sequestration without the performance and economic penalties associated with water gas shifting and separating CO{sub 2} from gas streams containing nitrogen. The cost estimate of the reference plant (the Foster Wheeler combustion hybrid) was based on a detailed prior study of a nominal 300 MWe demonstration plant with a 6F turbine. Therefore, the reference plant capital costs were found to be 30% higher than an estimate for a 425 MW fully commercial IGCC with an H class turbine (1438more » $/kW vs. 1111 $$/kW). Consequently, the capital cost of the CO{sub 2} hybrid plant was found to be 25% higher than that of the IGCC with pre-combustion CO{sub 2} removal (1892 $$/kW vs. 1510 $/kW), and the levelized cost of electricity (COE) was found to be 20% higher (7.53 c/kWh vs. 6.26 c/kWh). Although the final costs for the CO{sub 2} hybrid are higher, the study confirms that the relative change in cost (or mitigation cost) will be lower. The conceptual design of the plant and its performance and cost, including losses due to CO{sub 2} sequestration, is reported. Comparison with other proposed power plant CO{sub 2} removal techniques reported by a December 2000 EPRI report is shown. This project supports the DOE research objective of development of concepts for the capture and storage of CO{sub 2}.« less

Association between competitive food and beverage policies in elementary schools and childhood overweight/obesity trends: differences by neighborhood socioeconomic resources.

PubMed

Sanchez-Vaznaugh, Emma V; Sánchez, Brisa N; Crawford, Patricia B; Egerter, Susan

2015-05-01

To our knowledge, few published studies have examined the influence of competitive food and beverage (CF&B) policies on student weight outcomes; none have investigated disparities in the influence of CF&B policies on children's body weight by school neighborhood socioeconomic resources. To investigate whether the association between CF&B policies and population-level trends in childhood overweight/obesity differed by school neighborhood income and education levels. This cross-sectional study, from July 2013 to October 2014, compared overweight/obesity prevalence trends before (2001-2005) and after (2006-2010) implementation of CF&B policies in public elementary schools in California. The study included 2 700 880 fifth-grade students in 5362 public schools from 2001 to 2010. California CF&B policies (effective July 1, 2004, and July 1, 2007) and school neighborhood income and education levels. Overweight/obesity defined as a body mass index at or greater than the 85th percentile for age and sex. Overall rates of overweight/obesity ranged from 43.5% in 2001 to 45.8% in 2010. Compared with the period before the introduction of CF&B policies, overweight/obesity trends changed in a favorable direction after the policies took effect (2005-2010); these changes occurred for all children across all school neighborhood socioeconomic levels. In the postpolicy period, these trends differed by school neighborhood socioeconomic advantage. From 2005-2010, trends in overweight/obesity prevalence leveled off among students at schools in socioeconomically disadvantaged neighborhoods but declined in socioeconomically advantaged neighborhoods. Students in the lowest-income neighborhoods experienced zero or near zero change in the odds of overweight/obesity over time: the annual percentage change in overweight/obesity odds was 0.1% for females (95% CI, -0.7 to 0.9) and -0.3% for males (95% CI, -1.1 to 0.5). In contrast, in the highest-income neighborhoods, the annual percentage decline in the odds of overweight was 1.2% for females (95% CI, 0.4 to 1.9) and 1.0% for males (95% CI, 0.3 to 1.8). Findings were similar for school neighborhood education. Our study found population-level improvements in the prevalence of childhood overweight/obesity that coincided with the period following implementation of statewide CF&B policies (2005-2010). However, these improvements were greatest at schools in the most advantaged neighborhoods. This suggests that CF&B policies may help prevent child obesity; however, the degree of their effectiveness is likely to depend on socioeconomic and other contextual factors in school neighborhoods. To reduce disparities and prevent obesity, school policies and environmental interventions must address relevant contextual factors in school neighborhoods.

Comparison between male and female rats in a model of self-administration of a chocolate-flavored beverage: Behavioral and neurochemical studies.

PubMed

Contini, Andrea; Sanna, Fabrizio; Maccioni, Paola; Colombo, Giancarlo; Argiolas, Antonio

2018-05-15

The existence of sex differences was studied in a rat model of operant self-administration of a chocolate-flavored beverage (CFB), which possesses strong reinforcing properties and is avidly consumed by rats. Whether these differences occurred concomitantly to changes in extracellular dopamine in the dialysate obtained from the nucleus accumbens, was assessed by intracerebral microdialysis. Male, ovariectomized and intact female rats showed similar self-administration profiles, with minor differences in both acquisition and maintenance phases. Intact females self-administered larger amounts of CFB, when expressed per body weight, than males and ovariectomized females, in spite of similar values of lever-responding, latency to the first lever-response and consumption efficiency (a measure of rat's licking effectiveness) in males, ovariectomized and intact females and no difference in breakpoint value and number of lever-responses emerged when males, ovariectomized and intact females were exposed to a progressive ratio schedule of reinforcement. Intracerebral microdialysis revealed a slight but significant increase in dopamine activity in the shell of the nucleus accumbens of male rats when compared to intact female rats during CFB self-administration. The above differences may be caused by the hormonal (mainly estradiol) fluctuations that occur during the estrus cycle in intact females. Accordingly, in intact females CFB self-administration and dopamine activity were found to fluctuate across the estrus cycle, with lower parameters of CFB self-administration and lower dopamine activity in the Proestrus and Estrus phases vs. the Metestrus and Diestrus phases of the cycle. Copyright © 2018 Elsevier B.V. All rights reserved.

Effects of dietary calcium fructoborate supplementation on joint comfort and flexibility and serum inflammatory markers in dogs with osteoarthritis.

PubMed

Price, A K; de Godoy, M R C; Harper, T A; Knap, K E; Joslyn, S; Pietrzkowski, Z; Cross, B K; Detweiler, K B; Swanson, K S

2017-07-01

Our objective was to evaluate the short-term effects of calcium fructoborate (CFB) on gait, joint range of motion, serum inflammatory markers, and owner perception of pain in client-owned dogs. We used 59 osteoarthritic dogs with impairment, with dogs being randomly assigned to 4 treatments: placebo (60 mg fructose; = 15), low dose (69 mg CFB; = 14), high dose (127 mg CFB; = 14), or combination (69 mg CFB, 500 mg glucosamine hydrochloride and 200 mg chondroitin sulfate; = 16). Dogs up to 22.9 kg received 1 capsule/d, while dogs weighing 23 to 50 kg received 2 capsules/d. A physical examination, radiographs, goniometry measurements, gait analysis, blood sample collection, and a canine brief pain inventory questionnaire were performed on d 0 and 28. Change from baseline values were statistically analyzed among groups. After 28 d, dogs fed the low and high doses had an improved ( < 0.05) ability to rise from a lying position compared to placebo. Dogs fed the high dose also had a greater ( = 0.05) increase in soluble receptor for advanced glycation end products concentration than dogs fed the placebo. Sub-analysis of only large dogs (> 23 kg) showed that dogs fed the low dose had decreased ( < 0.05) pain severity score and pain at its worst compared to dogs fed the placebo. Large dogs fed the low dose also were shown to improve ( < 0.05) in their ability to rise from a lying position compared to dogs fed the placebo. Overall, CFB supplementation was well-tolerated and may aid in mitigating joint discomfort in dogs.

Association Between Competitive Food and Beverage Policies in Elementary Schools and Childhood Overweight/Obesity Trends

PubMed Central

Sanchez-Vaznaugh, Emma V.; Sánchez, Brisa N.; Crawford, Patricia B.; Egerter, Susan

2015-01-01

IMPORTANCE To our knowledge, few published studies have examined the influence of competitive food and beverage (CF&B) policies on student weight outcomes; none have investigated disparities in the influence of CF&B policies on children’s body weight by school neighborhood socioeconomic resources. OBJECTIVE To investigate whether the association between CF&B policies and population-level trends in childhood overweight/obesity differed by school neighborhood income and education levels. DESIGN, SETTING, AND PARTICIPANTS This cross-sectional study, from July 2013 to October 2014, compared overweight/obesity prevalence trends before (2001–2005) and after (2006–2010) implementation of CF&B policies in public elementary schools in California. The study included 2 700 880 fifth-grade students in 5362 public schools from 2001 to 2010. EXPOSURES California CF&B policies (effective July 1, 2004, and July 1, 2007) and school neighborhood income and education levels. MAIN OUTCOMES AND MEASURES Overweight/obesity defined as a body mass index at or greater than the 85th percentile for age and sex. RESULTS Overall rates of overweight/obesity ranged from 43.5% in 2001 to 45.8% in 2010. Compared with the period before the introduction of CF&B policies, overweight/obesity trends changed in a favorable direction after the policies took effect (2005–2010); these changes occurred for all children across all school neighborhood socioeconomic levels. In the postpolicy period, these trends differed by school neighborhood socioeconomic advantage. From 2005–2010, trends in overweight/obesity prevalence leveled off among students at schools in socioeconomically disadvantaged neighborhoods but declined in socioeconomically advantaged neighborhoods. Students in the lowest-income neighborhoods experienced zero or near zero change in the odds of overweight/obesity over time: the annual percentage change in overweight/obesity odds was 0.1% for females (95% CI, −0.7 to 0.9) and −0.3% for males (95% CI, −1.1 to 0.5). In contrast, in the highest-income neighborhoods, the annual percentage decline in the odds of overweight was 1.2% for females (95% CI, 0.4 to 1.9) and 1.0% for males (95% CI, 0.3 to 1.8). Findings were similar for school neighborhood education. CONCLUSIONS AND RELEVANCE Our study found population-level improvements in the prevalence of childhood overweight/obesity that coincided with the period following implementation of statewide CF&B policies (2005–2010). However, these improvements were greatest at schools in the most advantaged neighborhoods. This suggests that CF&B policies may help prevent child obesity; however, the degree of their effectiveness is likely to depend on socioeconomic and other contextual factors in school neighborhoods. To reduce disparities and prevent obesity, school policies and environmental interventions must address relevant contextual factors in school neighborhoods. PMID:25938657

EERC pilot-scale CFBC evaluation facility Project CFB test results. Topical report, Task 7.30

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mann, M.D.; Hajicek, D.R.; Henderson, A.K.

Project CFB was initiated at the University of North Dakota Energy and Environmental Research Center (EERC) in May 1988. Specific goals of the project were to (1) construct a circulating fluidized-bed combustor (CFBC) facility representative of the major boiler vendors` designs with the capability of producing scalable data, (2) develop a database for use in making future evaluations of CFBC technology, and (3) provide a facility for evaluating fuels, free of vendor bias for use in the - energy industry. Five coals were test-burned in the 1-MWth unit: North Dakota and Asian lignites, a Wyoming subbituminous, and Colorado and Pennsylvaniamore » bituminous coats. A total of 54 steady-state test periods were conducted, with the key test parameters being the average combustor temperature, excess air, superficial gas velocity, calcium-to-sulfur molar ratio, and the primary air-to-secondary air split. The capture for a coal fired in a CFBC is primarily dependent upon the total alkali-to-sulfur ratio. The required alkali-to ratio for 90% sulfur retention ranged from 1.4 to 4.9, depending upon coal type. While an alkali-to-ratio of 4.9 was required to meet 90% sulfur retention for the Salt Creek coal versus 1.4 for the Asian lignite, the total amount of sorbent addition required is much less for the Salt Creek coal, 4.2 pound sorbent per million Btu coal input, versus 62 pound/million Btu for the Asian lignite. The bituminous coals tested show optimal capture at combustor temperatures of approximately 1550{degree}F, with low-rank coals having optimal sulfur capture approximately 100{degree}F lower.« less

EERC pilot-scale CFBC evaluation facility Project CFB test results

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mann, M.D.; Hajicek, D.R.; Henderson, A.K.

Project CFB was initiated at the University of North Dakota Energy and Environmental Research Center (EERC) in May 1988. Specific goals of the project were to (1) construct a circulating fluidized-bed combustor (CFBC) facility representative of the major boiler vendors' designs with the capability of producing scalable data, (2) develop a database for use in making future evaluations of CFBC technology, and (3) provide a facility for evaluating fuels, free of vendor bias for use in the - energy industry. Five coals were test-burned in the 1-MWth unit: North Dakota and Asian lignites, a Wyoming subbituminous, and Colorado and Pennsylvaniamore » bituminous coats. A total of 54 steady-state test periods were conducted, with the key test parameters being the average combustor temperature, excess air, superficial gas velocity, calcium-to-sulfur molar ratio, and the primary air-to-secondary air split. The capture for a coal fired in a CFBC is primarily dependent upon the total alkali-to-sulfur ratio. The required alkali-to ratio for 90% sulfur retention ranged from 1.4 to 4.9, depending upon coal type. While an alkali-to-ratio of 4.9 was required to meet 90% sulfur retention for the Salt Creek coal versus 1.4 for the Asian lignite, the total amount of sorbent addition required is much less for the Salt Creek coal, 4.2 pound sorbent per million Btu coal input, versus 62 pound/million Btu for the Asian lignite. The bituminous coals tested show optimal capture at combustor temperatures of approximately 1550[degree]F, with low-rank coals having optimal sulfur capture approximately 100[degree]F lower.« less

Recycling of Sustainable Co-Firing Fly Ashes as an Alkali Activator for GGBS in Blended Cements

PubMed Central

Wu, Yann-Hwang; Huang, Ran; Tsai, Chia-Jung; Lin, Wei-Ting

2015-01-01

This study investigates the feasibility of co-firing fly ashes from different boilers, circulating fluidized beds (CFB) or stokers as a sustainable material in alkali activators for ground granulated blast-furnace slag (GGBS). The mixture ratio of GGBS and co-firing fly ashes is 1:1 by weight. The results indicate that only CF fly ash of CFB boilers can effectively stimulate the potential characteristics of GGBS and provide strength as an alkali activator. CF fly ash consists of CaO3 (48.5%), SiO2 (21.1%), Al2O3 (13.8%), SO3 (10.06%), Fe2O3 (2.25%) and others (4.29%). SA fly ash consists of Al2O3 (19.7%), SiO2 (36.3%), Fe2O3 (28.4%) and others (15.6%). SB fly ash consists of Al2O3 (15%), SiO2 (25.4%), Zn (20.6%), SO3 (10.9%), Fe2O3 (8.78%) and others (19.32%). The mixtures of SA fly ash and SB fly ash with GGBS, respectively, were damaged in the compressive strength test during seven days of curing. However, the built up strength of the CF fly ash and GGBS mixture can only be maintained for 7–14 days, and the compressive strength achieves 70% of that of a controlled group (cement in hardening cement paste). The strength of blended CF fly ash and GGBS started to decrease after 28 days, and the phenomenon of ettrigite was investigated due to the high levels of sulfur content. The CaO content in sustainable co-firing fly ashes must be higher than a certain percentage in reacting GGBS to ensure the strength of blended cements. PMID:28787970

Thermal degradation of paper industry wastes from a recovered paper mill using TGA. Characterization and gasification test.

PubMed

Arenales Rivera, Jorge; Pérez López, Virginia; Ramos Casado, Raquel; Sánchez Hervás, José-María

2016-01-01

In this survey, a refuse derived fuel (RDF) was produced from paper industry wastes through a mechanical treatment (MT). The two main wastes generated from a recovered paper mill were rejects and de-inking sludge, which were produced principally in the pulping and de-inking processes, respectively. This work presents raw wastes characterization, fuel preparation and gasification tests performed in a circulating fluidized bed (CFB) gasifier pilot plant. The characterization was carried out by proximate and ultimate analysis. Several blends of pre-conditioned rejects and de-inking sludge were densified by means of pelletizing, studying the energy consumption and its quality properties. Besides, thermal degradation of blends was studied under thermogravimetric analysis (TGA). The experimental runs were made from 30 to 900°C in nitrogen atmosphere at three heating ranges, β=5, 10 and 20°C/min. Two thermal stages were identified during the thermal degradation, which are linked to cellulose and plastic degradation. In addition, kinetics parameters were estimated by the application of non-isothermal methods: Kissinger-Akahira-Sunose (KAS), Flynn-Ozawa-Wall (FOW) and Coats and Redfern. The activation energy values were about 140-160 kJ/mol and 60-80 kJ/mol for plastic and cellulosic materials, respectively. Regarding waste valorisation, a blend composed of 95% of rejects and 5% of de-inking sludge was selected for gasification tests. The energy consumption during the preparation was recorded and a gasification tests were done to prove the usability of these pellets in a CFB gasifier. The main results were a net calorific value (NCV) of 5 MJ/Nm(3) and a total tar content of 11.44 g/Nm(3) at an equivalence ratio (ER) of 0.3. Copyright © 2015 Elsevier Ltd. All rights reserved.

Coexistence of alkaline-carbonatite complexes and high-MgO CFB in the Paranà-Etendeka province: Insights on plume-lithosphere interactions in the Gondwana realm

NASA Astrophysics Data System (ADS)

Natali, Claudio; Beccaluva, Luigi; Bianchini, Gianluca; Siena, Franca

2018-01-01

A careful review of petrological and geochemical data on the Paranà-Etendeka igneous province is reported, with particular attention being devoted to the relationships between high-MgO CFB (tholeiitic basalts-picrites) and nearly coeval alkaline-carbonatite complexes linked to the same extensional tectonics on a regional scale. At 135-130 Ma, the tectonomagmatic activity was focused in Etendeka, the centre of the restored province, and characterised by an exclusive occurrence of the hottest and deepest high-MgO CFB (potential temperature Tp up to 1590 °C and pressure up to 5 GPa) possessing the same Sr-Nd-Pb isotopic composition of the "Gough" geochemical component, a marker of the initial Tristan plume activity. Etendeka high-MgO CFB thus represent the most genuine proxies of sublithospheric melts generated at the plume axis and are relatively unaffected by lithospheric contamination. Nearly coeval (133-128 Ma) alkaline‑carbonatite complexes cluster around the extensional structures of the Ponta Grossa Arch (e.g., Jacupiranga and Juquia in Brazil) and the Damara Belt (e.g., Erongo, Okurusu, Okenyenya and Paresis in Namibia), both of which intersect the early track of the south Atlantic opening. Compared to high-MgO CFB, alkaline magmas display distinctive isotopic signatures and an incompatible element distribution consistent with their generation from lithospheric mantle sources, which were variably metasomatised (veined?) by amphibole and phlogopite. Metasomes of alkaline mantle sources have a HIMU affinity and are dominated by amphibole in Namibia, whereas they display EM1 tendency and a more relevant role of phlogopite in Brazil, which implies important lithospheric differences at a regional scale. The tectonomagmatic features of Paranà-Etendeka -also shared by other Gondwana LIPs, such as Deccan and Karoo- can be reconciled by a generalized model where a hot plume impinging on a relatively thick lithosphere caused, in the axial zone, the contemporaneous generation and rise of high-MgO CFB and alkaline magmas from distinct asthenospheric and lithospheric mantle sources, respectively. In the asthenosphere, the volatile-poor solidus was crossed under an adiabatic thermal regime, mostly in the range of 4 to 5 GPa and Tp 1500 to 1600 °C with the development of high-MgO CFB. In the overlying metasomatised lithosphere, the plume effects caused a perturbation of the conductive thermal regime and a crossing of volatile-rich solidus (mostly P 2-3 GPa, Tp 1300-1400 °C) with the generation of alkaline melts from the most fusible (hydrated and carbonated) mantle domains.

Pyrolysis of waste tyres: a review.

PubMed

Williams, Paul T

2013-08-01

Approximately 1.5 billion tyres are produced each year which will eventually enter the waste stream representing a major potential waste and environmental problem. However, there is growing interest in pyrolysis as a technology to treat tyres to produce valuable oil, char and gas products. The most common reactors used are fixed-bed (batch), screw kiln, rotary kiln, vacuum and fluidised-bed. The key influence on the product yield, and gas and oil composition, is the type of reactor used which in turn determines the temperature and heating rate. Tyre pyrolysis oil is chemically very complex containing aliphatic, aromatic, hetero-atom and polar fractions. The fuel characteristics of the tyre oil shows that it is similar to a gas oil or light fuel oil and has been successfully combusted in test furnaces and engines. The main gases produced from the pyrolysis of waste tyres are H(2), C(1)-C(4) hydrocarbons, CO(2), CO and H(2)S. Upgrading tyre pyrolysis products to high value products has concentrated on char upgrading to higher quality carbon black and to activated carbon. The use of catalysts to upgrade the oil to a aromatic-rich chemical feedstock or the production of hydrogen from waste tyres has also been reported. Examples of commercial and semi-commercial scale tyre pyrolysis systems show that small scale batch reactors and continuous rotary kiln reactors have been developed to commercial scale. Copyright © 2013 Elsevier Ltd. All rights reserved.

Preparation of steam activated carbon from rubberwood sawdust (Hevea brasiliensis) and its adsorption kinetics.

PubMed

Prakash Kumar, B G; Shivakamy, K; Miranda, Lima Rose; Velan, M

2006-08-25

Activated carbon was produced from a biowaste product, rubberwood sawdust (RWSD) using steam in a high temperature fluidized bed reactor. Experiments were carried out to investigate the influence of various process parameters such as activation time, activation temperature, particle size and fluidising velocity on the quality of the activated carbon. The activated carbon was characterized based on its iodine number, methylene blue number, Brauner Emmet Teller (BET) surface area and surface area obtained using the ethylene glycol mono ethyl ether (EGME) retention method. The best quality activated carbon was obtained at an activation time and temperature of 1h and 750 degrees C for an average particle size of 0.46 mm. The adsorption kinetics shows that pseudo-second-order rate fitted the adsorption kinetics better than pseudo-first-order rate equation. The adsorption capacity of carbon produced from RWSD was found to be 1250 mg g(-1) for the Bismark Brown dye. The rate constant and diffusion coefficient for intraparticle transport were determined for steam activated carbon. The characteristic of the prepared activated carbon was found comparable to the commercial activated carbon.

Three years experience of operating and selling recovered struvite from full-scale plant.

PubMed

Ueno, Y; Fujii, M

2001-11-01

The adoption of phosphorus removal at sewage treatment works (STW) creates two main problems. Firstly large amounts of sludge are produced and secondly the quantity of the effluent deteriorates due to the increase in the phosphorus load of the sidestream. Furthermore, these processes do not remove phosphorus in a form that would enable it to be recycled. Therefore in order to control these process difficulties and produce a recyclable phosphorus product a sidestream struvite crystallisation reactor was developed. The struvite was produced in a fluidised bed reactor using dewatered filtrate from anaerobic sludge digestion. Magnesium hydroxide was added in a magnesium to phosphate ratio of 1:1 and the pH was adjusted to between 8.2-8.8 with the addition of sodium hydroxide. A retention time of 10 days alowed the growth of pellets between 0.5-1.0 mm in size. The recovered struvite contained only minute traces of toxic substances and was sold to fertiliser companies for 27,000 yen tonne(-1). It is used to enhance existing fertilisers, which are widely used on paddy rice, vegetables and flowers.

Organic compounds leached from fast pyrolysis mallee leaf and bark biochars.

PubMed

Lievens, Caroline; Mourant, Daniel; Gunawan, Richard; Hu, Xun; Wang, Yi

2015-11-01

Characterization of organic compounds leached from biochars is essential in assessing the possible toxicity of the biochar to the soils' biota. In this study the nature of the leached organic compounds from Mallee biochars, produced from pyrolysis of Mallee leaf and bark in a fluidised-bed pyrolyser at 400 and 580°C was investigated. Light bio-oil compounds and aromatic organic compounds were investigated. The 'bio-oil like' light compounds from leaf and bark biochars 'surfaces were obtained after leaching the chars with a solvent, suitable to dissolve the respective bio-oils. GC/MS was implemented to investigate the leachates. Phenolics, which are potentially harmful toxins, were detected and their concentration shown to be dependent on the char's origin and the char production temperature. Further, to simulate biochars amendment to soils, the chars were leached with water. The water-leached aromatic compounds from leaf and bark biochars were characterized using UV-fluorescence spectroscopy. Those results suggested that biochars contain leachable compounds of which the nature and amount is dependent on the biomass feedstock, pyrolysis temperature and leaching time. Copyright © 2014 Elsevier Ltd. All rights reserved.

Emission characteristics for gaseous- and size-segregated particulate PAHs in coal combustion flue gas from circulating fluidized bed (CFB) boiler.

PubMed

Wang, Ruwei; Liu, Guijian; Sun, Ruoyu; Yousaf, Balal; Wang, Jizhong; Liu, Rongqiong; Zhang, Hong

2018-07-01

The partitioning behavior of polycyclic aromatic hydrocarbons (PAHs) between gaseous and particulate phases from coal-fired power plants (CFPPs) is critically important to predict PAH removal by dust control devices. In this study, 16 US-EPA priority PAHs in gaseous and size-segregated particulate phases at the inlet and outlet of the fabric filter unit (FFs) of a circulating fluidized bed (CFB) boiler were analyzed. The partitioning mechanisms of PAHs between gaseous and particulate phases and in particles of different size classes were investigated. We found that the removal efficiencies of PAHs are 45.59% and 70.67-89.06% for gaseous and particulate phases, respectively. The gaseous phase mainly contains low molecular weight (LMW) PAHs (2- and 3-ring PAHs), which is quite different from the particulate phase that mainly contains medium and high molecular weight (MMW and HMW) PAHs (4- to 6-ring PAHs). The fractions of LMW PAHs show a declining trend with the decrease of particle size. The gas-particle partitioning of PAHs is primarily controlled by organic carbon absorption, in addition, it has a clear dependence on the particle sizes. Plot of log (TPAH/PM) against logD p shows that all slope values were below -1, suggesting that PAHs were mainly adsorbed to particulates. The adsorption effect of PAHs in size-segregated PMs for HMW PAHs is more evident than LMW PAHs. The particle size distributions (PSDs) of individual PAHs show that most of PAHs exhibit bi-model structures, with one mode peaking in the accumulation size range (2.1-1.1 μm) and another mode peaking in coarse size range (5.8-4.7 μm). The intensities of these two peaks vary in function of ring number of PAHs, which is likely attributed to Kelvin effect that the less volatile HMW PAH species preferentially condense onto the finer particulates. The emission factor of PAHs was calculated as 3.53 mg/kg of coal burned, with overall mean EF PAH of 0.55 and 2.98 mg/kg for gaseous and particulate phase, respectively. Moreover, the average emission amount of PAHs for the investigated CFPP was 1016.6 g/day and 371073.6 g/y, respectively. Copyright © 2018 Elsevier Ltd. All rights reserved.

Complement Factor B is the Downstream Effector of Toll-Like Receptors and Plays an Important Role in a Mouse Model of Severe Sepsis¶

PubMed Central

Zou, Lin; Feng, Yan; Li, Yan; Zhang, Ming; Chen, Chan; Cai, Jiayan; Gong, Yu; Wang, Larry; Thurman, Joshua M.; Wu, Xiaobo; Atkinson, John P.; Chao, Wei

2013-01-01

Severe sepsis involves massive activation of the innate immune system and leads to high mortality. Previous studies have demonstrated that various types of Toll-like receptors (TLRs) mediate a systemic inflammatory response and contribute to organ injury and mortality in animal models of severe sepsis. However, the downstream mechanisms responsible for TLR-mediated septic injury are poorly understood. Here, we show that activation of TLR2, TLR3 and TLR4 markedly enhanced complement factor B (cfB) synthesis and release by macrophages and cardiac cells. Polymicrobial sepsis, created by cecal ligation and puncture (CLP) in a mouse model, augmented cfB levels in the serum, peritoneal cavity and major organs including the kidney and heart. CLP also led to the alternative pathway (AP) activation, C3 fragment deposition in the kidney and heart, and cfB-dependent C3dg elevation. Bacteria isolated from septic mice activated the serum AP via a factor D-dependent manner. MyD88 deletion attenuated cfB/C3 up-regulation as well as cleavage induced by polymicrobial infection. Importantly, during sepsis, absence of cfB conferred a protective effect with improved survival and cardiac function, and markedly attenuated acute kidney injury. cfB deletion also led to increased neutrophil migratory function during the early phase of sepsis, decreased local and systemic bacterial load, attenuated cytokine production and reduced neutrophil reactive oxygen species production. Together, our data indicate that cfB acts as a downstream effector of TLR signaling and plays a critical role in the pathogenesis of severe bacterial sepsis. PMID:24154627

Combustion of Schlamm in ACFB boilers -- The Charbonnages de France Group's experience

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schroeder, M.; Rollin, J.P.

Within the context of the rehabilitation of Emile Huchet Power Plant Unit 4 owned by the ``SNET'', a company of the CHARBONNAGES DE FRANCE Group, a new CFB boiler with an electrical capacity of 125 MW has been commissioned in 1990 in replacement for an existing pulverized-coal boiler. This boiler constituted at the time an experimental unit on two accounts. It was an innovation through its size but also its specific design which allows to burn schlamm--a coal washing residue--in the form of pulp. The boiler design answered the CHARBONNAGES DE FRANCE Group's need to eliminate old settling ponds containingmore » schlamm which, from the technical and economic point of view, could not be burnt using conventional combustion techniques owing to its specific characteristics (fine, high-ash product with a very high moisture and clay content). This original method of injection as well as the pulp preparation process suited to this type of injection have been designed and developed by CdF INGENIERIE and the CERCHAR (CdF Group) after many investigations and tests. The experience gained at Emile Huchet Power Plant for more than 7 years confirms that the CFB boiler is a clean combustion technique which is perfectly suited to the combustion of schlamm injected in the form of pulp. The CFB unit burns exclusively schlamm conditioned in the form of pulp with 33% of moisture, and this with a high degree of efficiency, low emission values and a very good availability. This talk include a description of the CFB boiler and the pulp preparation plant as well as a presentation of the boiler performances and of the experience gained by the CHARBONANGES DE FRANCE Group since the new CFB unit has been commissioned.« less

Topical tofacitinib for atopic dermatitis: a phase IIa randomized trial.

PubMed

Bissonnette, R; Papp, K A; Poulin, Y; Gooderham, M; Raman, M; Mallbris, L; Wang, C; Purohit, V; Mamolo, C; Papacharalambous, J; Ports, W C

2016-11-01

Despite unmet need, 15 years have passed since a topical therapy with a new mechanism of action for atopic dermatitis (AD) has been approved. Janus kinase (JAK) inhibitor treatment effect via topical application in patients with AD is unknown. Tofacitinib, a small-molecule JAK inhibitor, was investigated for the topical treatment of AD. In this 4-week, phase IIa, randomized, double-blind, vehicle-controlled study (NCT02001181), 69 adults with mild-to-moderate AD were randomized 1:1 to 2% tofacitinib or vehicle ointment twice daily. Percentage change from baseline (CFB) in Eczema Area and Severity Index (EASI) score at week 4 was the primary end point. Secondary efficacy end points included percentage CFB in body surface area (BSA), CFB in EASI Clinical Signs Severity Sum Score, proportion of patients with Physician's Global Assessment (PGA) response and CFB in patient-reported pruritus. Safety, local tolerability and pharmacokinetics were monitored. The mean percentage CFB at week 4 in EASI score was significantly greater (P < 0·001) for tofacitinib (-81·7%) vs. vehicle (-29·9%). Patients treated with tofacitinib showed significant (P < 0·001) improvements vs. vehicle across all prespecified efficacy end points and for pruritus at week 4. Significant improvements in EASI, PGA and BSA were observed by week 1 and improvements in pruritus were observed by day 2. Safety/local tolerability were generally similar for both treatments, although more adverse events were observed for vehicle vs. tofacitinib. Tofacitinib ointment showed significantly greater efficacy vs. vehicle across end points, with early onset of effect and comparable safety/local tolerability to vehicle. JAK inhibition through topical delivery is potentially a promising therapeutic target for AD. © 2016 The Authors. British Journal of Dermatology published by John Wiley & Sons Ltd on behalf of British Association of Dermatologists.

The Second-Generation Maturation Inhibitor GSK3532795 Maintains Potent Activity Toward HIV Protease Inhibitor-Resistant Clinical Isolates.

PubMed

Ray, Neelanjana; Li, Tianbo; Lin, Zeyu; Protack, Tricia; van Ham, Petronella Maria; Hwang, Carey; Krystal, Mark; Nijhuis, Monique; Lataillade, Max; Dicker, Ira

2017-05-01

Protease inhibitor (PI)-resistant HIV-1 isolates with primary substitutions in protease (PR) and secondary substitutions in Gag could potentially exhibit cross-resistance to maturation inhibitors. We evaluated the second-generation maturation inhibitor, GSK3532795, for activity toward clinical isolates with genotypic and phenotypic characteristics associated with PI resistance (longitudinal). Longitudinal clinical isolates from 15 PI-treated patients and 7 highly PI-resistant (nonlongitudinal) viruses containing major and minor PI resistance-associated mutations were evaluated for GSK3532795 sensitivity. Phenotypic sensitivity was determined using the PhenoSense Gag/PR assay (Monogram Biosciences) or in-house single- and multiple-cycle assays. Changes from baseline [CFB; ratio of post- to pre-treatment FC-IC50 (fold-change in IC50 versus wild-type virus)] <3 were considered to be within the no-effect level. All nonlongitudinal viruses tested were sensitive to GSK3532795 (FC-IC50 range 0.16-0.68). Among longitudinal isolates, all post-PI treatment samples had major PI resistance-associated mutations in PR and 17/21 had PI resistance-associated changes in Gag. Nineteen of the 21 post-PI treatment samples had GSK3532795 CFB <3. Median (range) CFB was 0.83 (0.05-27.4) [Monogram (11 patients)] and 1.5 (1.0-2.2) [single-cycle (4 patients)]. The 2 post-PI treatment samples showing GSK3532795 CFB >3 (Monogram) were retested using single- and multiple-cycle assays. Neither sample had meaningful sensitivity changes in the multiple-cycle assay. Gag changes were not associated with an increased GSK3532795 CFB. GSK3532795 maintained antiviral activity against PI-resistant isolates with emergent PR and/or Gag mutations. This finding supports continued development of GSK3532795 in treatment-experienced patients with or without previous PI therapy.

Wildfire spread, hazard and exposure metric raster grids for central Catalonia.

PubMed

Alcasena, Fermín J; Ager, Alan A; Salis, Michele; Day, Michelle A; Vega-Garcia, Cristina

2018-04-01

We provide 40 m resolution wildfire spread, hazard and exposure metric raster grids for the 0.13 million ha fire-prone Bages County in central Catalonia (northeastern Spain) corresponding to node influence grid (NIG), crown fraction burned (CFB) and fire transmission to residential houses (TR). Fire spread and behavior data (NIG, CFB and fire perimeters) were generated with fire simulation modeling considering wildfire season extreme fire weather conditions (97 th percentile). Moreover, CFB was also generated for prescribed fire (Rx) mild weather conditions. The TR smoothed grid was obtained with a geospatial analysis considering large fire perimeters and individual residential structures located within the study area. We made these raster grids available to assist in the optimization of wildfire risk management plans within the study area and to help mitigate potential losses from catastrophic events.

Climate-driven speedup of alpine treeline forest growth in the Tianshan Mountains, Northwestern China.

PubMed

Qi, Zhaohuan; Liu, Hongyan; Wu, Xiuchen; Hao, Qian

2015-02-01

Forest growth is sensitive to interannual climatic change in the alpine treeline ecotone (ATE). Whether the alpine treeline ecotone shares a similar pattern of forest growth with lower elevational closed forest belt (CFB) under changing climate remains unclear. Here, we reported an unprecedented acceleration of Picea schrenkiana forest growth since 1960s in the ATE of Tianshan Mountains, northwestern China by a stand-total sampling along six altitudinal transects with three plots in each transect: one from the ATE between the treeline and the forest line, and the other two from the CFB. All the sampled P. schrenkiana forest patches show a higher growth speed after 1960 and, comparatively, forest growth in the CFB has sped up much slower than that in the ATE. The speedup of forest growth at the ATE is mainly accounted for by climate factors, with increasing temperature suggested to be the primary driver. Stronger water deficit as well as more competition within the CFB might have restricted forest growth there more than that within the ATE, implying biotic factors were also significant for the accelerated forest growth in the ATE, which should be excluded from simulations and predictions of warming-induced treeline dynamics. © 2014 John Wiley & Sons Ltd.

Electronic and mechanical properties of half-metallic half-Heusler compounds CoCrZ (Z = S, Se, and Te)

NASA Astrophysics Data System (ADS)

Huang, Hai-Ming; Zhang, Chuan-Kun; He, Ze-Dong; Zhang, Jun; Yang, Jun-Tao; Luo, Shi-Jun

2018-01-01

Not Available Project supported by the National Natural Science Foundation of China (Grant Nos. 11647133 and 11674113), the Natural Science Foundation of Hubei Province, China (Grant Nos. 2017CFB740 and 2014CFB631), the Scientific Research Items Foundation of Hubei Educational Committee, China (Grant Nos. Q20141802, Q20161803, B2016091, and D20171803), and Hubei Provincial Collaborative Innovation Center for Optoelectronics, China.

Reburning Characteristics of Residual Carbon in Fly Ash from CFB Boilers

NASA Astrophysics Data System (ADS)

Zhang, S. H.; Luo, H. H.; Chen, H. P.; Yang, H. P.; Wang, X. H.

The content of residual carbon in fly ash of CFB boilers is a litter high especially when low-grade coal, such as lean coal, anthracite coal, gangue, etc. is in service, which greatly influences the efficiency of boilers and fly ash further disposal. Reburn of fly ash through collection, recirculation in CFB furnace or external combustor is a possibly effective strategy to decrease the carbon content, mainly depending on the residual carbon reactivity. In this work, the combustion properties of residual carbon in fly ash and corresponding original coal from large commercial CFB boilers (Kaifeng (440t/h), and Fenyi (410t/h), all in china) are comparably investigated through experiments. The residual carbon involved was firstly extracted and enriched from fly ash by means of floating elutriation to mitigate the influence of ash and minerals on the combustion behavior of residual carbon. Then, the combustion characteristic of two residual carbons and the original coal particles was analyzed with thermogravimetric analyzer (TGA, STA409C from Nestch, Germany). It was observed that the ignition temperature of the residual carbon is much higher than that of original coal sample, and the combustion reactivity of residual carbon is not only dependent on the original coal property, but also the operating conditions. The influence of oxygen content and heating rate was also studied in TGA. The O2 concentration is set as 20%, 30%, 40% and 70% respectively in O2/N2 gas mixture with the flow rate of 100ml/min. It was found that higher oxygen content is favor for decreasing ignition temperature, accelerating the combustion rate of residual carbon. And about 40% of oxygen concentration is experimentally suggested as an optimal value when oxygen-enriched combustion is put into practice for decreasing residual carbon content of fly ash in CFB boilers.

Sphingosine-1-phosphate receptor expression in cardiac fibroblasts is modulated by in vitro culture conditions.

PubMed

Landeen, Lee K; Aroonsakool, Nakon; Haga, Jason H; Hu, Betty S; Giles, Wayne R

2007-06-01

The bioactive molecule sphingosine-1-phosphate (S1P) binds with high affinity to five recognized receptors (S1P(1-5)) to affect various tissues, including cellular responses of cardiac fibroblasts (CFbs) and myocytes. CFbs are essential components of myocardium, and detailed study of their cell signaling and physiology is required for a number of emerging disciplines. Meaningful studies on CFbs, however, necessitate methods for selective, reproducible cell isolations. Macrophages reside within normal cardiac tissues and often are isolated with CFbs. A protocol was therefore developed that significantly reduces macrophage levels and utilizes more CFb-specific markers (discoidin domain receptor-2) instead of, or in addition to, more commonly used cytoskeletal markers. Our results demonstrate that primary isolated, purified CFbs express predominantly S1P(1-3); however, the relative levels of these receptor subtypes are modulated with time and by culture conditions. In coculture experiments, macrophages altered CFb S1P receptor levels relative to controls. Further investigations using known macrophage-secreted factors showed that S1P and H(2)O(2) had minimal effects on CFb S1P(1-3) expression, whereas transforming growth factor-beta1, TNF-alpha, and PDGF-BB significantly altered all S1P receptor subtypes. Lowering FBS concentrations from 10% to 0.1% increased S1P(2), whereas supplementation with either PDGF-BB or Rho-associated protein kinase inhibitor Y-27632 significantly elevated S1P(3) levels. S1P(2) and S1P(3) receptor levels are known to regulate cell migration. Using cells isolated from either normal or S1P(3)-null mice, we demonstrate that S1P(3) is important and necessary for CFb migration. These results highlight the importance of demonstrating CFb culture purity in functional studies of S1P and also identify conditions that modulate S1P receptor expression in CFbs.

The Second-Generation Maturation Inhibitor GSK3532795 Maintains Potent Activity Toward HIV Protease Inhibitor–Resistant Clinical Isolates

PubMed Central

Ray, Neelanjana; Li, Tianbo; Lin, Zeyu; Protack, Tricia; van Ham, Petronella Maria; Hwang, Carey; Krystal, Mark; Nijhuis, Monique; Lataillade, Max

2017-01-01

Background: Protease inhibitor (PI)-resistant HIV-1 isolates with primary substitutions in protease (PR) and secondary substitutions in Gag could potentially exhibit cross-resistance to maturation inhibitors. We evaluated the second-generation maturation inhibitor, GSK3532795, for activity toward clinical isolates with genotypic and phenotypic characteristics associated with PI resistance (longitudinal). Methods: Longitudinal clinical isolates from 15 PI-treated patients and 7 highly PI-resistant (nonlongitudinal) viruses containing major and minor PI resistance-associated mutations were evaluated for GSK3532795 sensitivity. Phenotypic sensitivity was determined using the PhenoSense Gag/PR assay (Monogram Biosciences) or in-house single- and multiple-cycle assays. Changes from baseline [CFB; ratio of post- to pre-treatment FC-IC50 (fold-change in IC50 versus wild-type virus)] <3 were considered to be within the no-effect level. Results: All nonlongitudinal viruses tested were sensitive to GSK3532795 (FC-IC50 range 0.16–0.68). Among longitudinal isolates, all post-PI treatment samples had major PI resistance-associated mutations in PR and 17/21 had PI resistance-associated changes in Gag. Nineteen of the 21 post-PI treatment samples had GSK3532795 CFB <3. Median (range) CFB was 0.83 (0.05–27.4) [Monogram (11 patients)] and 1.5 (1.0–2.2) [single-cycle (4 patients)]. The 2 post-PI treatment samples showing GSK3532795 CFB >3 (Monogram) were retested using single- and multiple-cycle assays. Neither sample had meaningful sensitivity changes in the multiple-cycle assay. Gag changes were not associated with an increased GSK3532795 CFB. Conclusions: GSK3532795 maintained antiviral activity against PI-resistant isolates with emergent PR and/or Gag mutations. This finding supports continued development of GSK3532795 in treatment-experienced patients with or without previous PI therapy. PMID:28234686

Covariate determinants of effective dosing regimens for time-dependent beta-lactam antibiotics for critically ill patients.

PubMed

Kaska, Milan; Havel, Eduard; Selke-Krulichova, Iva; Safranek, Petr; Bezouska, Jan; Martinkova, Jirina

2018-03-27

Critically ill patients undergoing aggressive fluid resuscitation and treated empirically with hydrosoluble time-dependent beta-lactam antibiotics are at risk for sub-therapeutic plasma concentrations. The aim of this study was to assess the impact of two covariates - creatinine clearance (Cl cr ) and cumulative fluid balance (CFB) on pharmacokinetics/pharmacodynamics (PK/PD) target attainment within a week of treatment with meropenem (ME) or piperacillin/tazobactam (PIP/TZB). In this prospective observational pharmacokinetic (PK) study, 18 critically ill patients admitted to a surgical Intensive Care Unit (ICU) were enrolled. The primary PK/PD target was free antibiotic concentrations above MIC at 100% of the dosing interval (100%fT>MIC) to obtain maximum bactericidal activity. Drug concentration was measured using liquid chromatography-tandem mass spectrometry. The treatment of both 8 septic patients with IV extended ME dosing 2 g/3 h q8 h and 10 polytraumatized patients with IV intermittent PIP/TZB dosing 4.0/0.5 g q8 h was monitored. 8/18 patients (44%) manifested augmented renal clearence (ARC) where Cl cr ≥130 mL/min/1.73m 2 . Maximum changes were reported on days 2-3: the median positive CFB followed by the large median volume of distribution: Vd me =70.3 L (41.9-101.5), Vd pip = 46.8 L (39.7-60.0). 100%fT me >MIC was achieved in all patients on ME (aged ≥60 years), and only in two patients (non-ARC, aged ≥65 years) out of 10 on PIP/TZB. A mixed model analysis revealed positive relationship of CFB pip with Vd pip (P=0.021). Assuming that the positive correlation between CFB and Vd exists for piperacillin in the setting of the pathological state, then CFB should predict Vd pip across subjects at each and every time point.

Transient Characterization of Type B Particles in a Transport Riser

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shadle, L.J.; Monazam, E.R.; Mei, J.S.

2007-01-01

Simple and rapid dynamic tests were used to evaluate fluid dynamic behavior of granular materials in the transport regime. Particles with densities ranging from 189 to 2,500 kg/m3 and Sauter mean size from 61 to 812 μm were tested in a 0.305 m diameter, 15.5 m height circulating fluidized bed (CFB) riser. The transient tests involved the abrupt stoppage of solids flow for each granular material over a wide range gas flow rates. The riser emptying time was linearly related to the Froude number in each of three different operating regimes. The flow structure along the height of the risermore » followed a distinct pattern as tracked through incremental pressures. These results are discussed to better understand the transformations that take place when operating over various regimes. During the transients the particle size distribution was measured. The effects of pressure, particle size, and density on test performance are also presented.« less

Comparative study on direct burning of oil shale and coal

NASA Astrophysics Data System (ADS)

Hammad, Ahmad; Al Asfar, Jamil

2017-07-01

A comparative study of the direct burning processes of oil shale and coal in a circulating fluidized bed (CFB) was done in this study using ANSYS Fluent software to solve numerically the governing equations of continuity, momentum, energy and mass diffusion using finite volume method. The model was built based on an existing experimental combustion burner unit. The model was validated by comparing the theoretical results of oil shale with proved experimental results from the combustion unit. It was found that the temperature contours of the combustion process showed that the adiabatic flame temperature was 1080 K for oil shale compared with 2260 K for coal, while the obtained experimental results of temperatures at various locations of burner during the direct burning of oil shale showed that the maximum temperature reached 962 K for oil shale. These results were used in economic and environmental analysis which show that oil shale may be used as alternative fuel for coal in cement industry in Jordan.

A Projectile for a Rectangular Barreled Rail Gun

DTIC Science & Technology

1999-12-01

fins Cfb ’ skin friction drag coefficient for nose/body combination modified for equations of motion Cff’ skin friction drag coefficient for fins...occasionally referred to as the last point method, uses a loop , shown in simplified form in Figure (2) as a flow chart. The program loop takes the final... Cfb ’ = CfofCf(Sno/s+Sbs)/ScsS (4.11) Cff = CfffcfSw/Scss (4.12) 2. Form Drag The form drag coefficients are determined by the methods from

MP-Pic simulation of CFB riser with EMMS-based drag model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, F.; Song, F.; Benyahia, S.

2012-01-01

MP-PIC (multi-phase particle in cell) method combined with the EMMS (energy minimization multi- scale) drag force model was implemented with the open source program MFIX to simulate the gas–solid flows in CFB (circulatingfluidizedbed) risers. Calculated solid flux by the EMMS drag agrees well with the experimental value; while the traditional homogeneous drag over-predicts this value. EMMS drag force model can also predict the macro-and meso-scale structures. Quantitative comparison of the results by the EMMS drag force model and the experimental measurements show high accuracy of the model. The effects of the number of particles per parcel and wall conditions onmore » the simulation results have also been investigated in the paper. This work proved that MP-PIC combined with the EMMS drag model can successfully simulate the fluidized flows in CFB risers and it serves as a candidate to realize real-time simulation of industrial processes in the future.« less

Calcite-forming bacteria for compressive strength improvement in mortar.

PubMed

Park, Sung-Jin; Park, Yu-Mi; Chun, Woo-Young; Kim, Wha-Jung; Ghim, Sa-Youl

2010-04-01

Microbiological calcium carbonate precipitation (MCP) has been investigated for its ability to improve the compressive strength of concrete mortar. However, very few studies have been conducted on the use of calcite-forming bacteria (CFB) to improve compressive strength. In this study, we discovered new bacterial genera that are capable of improving the compressive strength of concrete mortar. We isolated 4 CFB from 7 environmental concrete structures. Using sequence analysis of the 16S rRNA genes, the CFB could be partially identified as Sporosarcina soli KNUC401, Bacillus massiliensis KNUC402, Arthrobacter crystallopoietes KNUC403, and Lysinibacillus fusiformis KNUC404. Crystal aggregates were apparent in the bacterial colonies grown on an agar medium. Stereomicroscopy, scanning electron microscopy, and x-ray diffraction analyses illustrated both the crystal growth and the crystalline structure of the CaCO3 crystals. We used the isolates to improve the compressive strength of concrete mortar cubes and found that KNUC403 offered the best improvement in compressive strength.

Bromine and Chlorine in Aerosols and Fly Ash when Co-Firing Solid Recovered Fuel, Spruce Bark and Paper Mill Sludge in a 80MWth BFB Boiler

NASA Astrophysics Data System (ADS)

Vainikka, P.; Silvennoinen, J.; Yrjas, P.; Frantsi, A.; Hietanen, L.; Hupa, M.; Taipale, R.

Aerosol and fly ash sampling was carried out at a 80MWth bubbling fluidised bed (BFB) boiler plant co-firing solid recovered fuel (SRF), spruce bark and paper mill wastewater sludge in two experimental conditions. The SRF-Bark ratio in the fuel mix was kept constant at 50%-50% on dry mass basis in both experiments but two sludge proportions were used: 15% and 4% on dry mass basis. Aerosol samples were collected from the superheater region of the boiler furnace and fly ash from the electrostatic precipitator (ESP). Na, K, Cl and S were found to be in mainly water soluble compounds in the aerosols sampled by means of a Dekati type Low Pressure Impactor (DLPI). Bromine was found in several weight percentages in aerosols and it was amongst the main elements in some of the samples collected. Bromine is assumed to mainly originate from flame retarded plastics and textiles in the SRF. According to the measurements, the fate of Br seems to be analogous to the other main halogen, Cl, and its conversion from fuel to aerosols was high, indicating a strong tendency to form bromine salts.

Solidification of nanosuspensions for the production of solid oral dosage forms and inhalable dry powders.

PubMed

Malamatari, Maria; Somavarapu, Satyanarayana; Taylor, Kevin M G; Buckton, Graham

2016-01-01

Nanosuspensions combine the advantages of nanotherapeutics (e.g. increased dissolution rate and saturation solubility) with ease of commercialisation. Transformation of nanosuspensions to solid oral and inhalable dosage forms minimises the physical instability associated with their liquid state, enhances patient compliance and enables targeted oral and pulmonary drug delivery. This review outlines solidification methods for nanosuspensions. It includes spray and freeze drying as the most widely used techniques. Fluidised-bed coating, granulation and pelletisation are also discussed as they yield nanocrystalline formulations with more straightforward downstream processing to tablets or capsules. Spray-freeze drying, aerosol flow reactor and printing of nanosuspensions are also presented as promising alternative solidification techniques. Results regarding the solid state, in vitro dissolution and/or aerosolisation efficiency of the nanocrystalline formulations are given and combined with available in vivo data. Focus is placed on the redispersibility of the solid nanocrystalline formulations, which is a prerequisite for their clinical application. A few solidified nanocrystalline products are already on the market and many more are in development. Oral and inhalable nanoparticle formulations are expected to have great potential especially in the areas of personalised medicine and delivery of high drug doses (e.g. antibiotics) to the lungs, respectively.

The perfect ash-storm: large-scale Pyroclastic Density Current experiments reveal highly mobile, self-fluidising and air-cushioned flow transport regime

NASA Astrophysics Data System (ADS)

Lube, G.; Cronin, S. J.; Breard, E.; Valentine, G.; Bursik, M. I.; Hort, M. K.; Freundt, A.

2013-12-01

We report on the first systematic series of large-scale Pyroclastic Density Current (PDC) experiments using the New Zealand PDC Generator, a novel international research facility in Physical Volcanology recently commissioned at Massey University. Repeatable highly energetic and hot PDCs are synthesized by the controlled ';eruption column-collapse' of up to 3500 kg of homogenously aerated Taupo ignimbrite material from a 15 m-elevated hopper onto an instrumented inclined flume. At discharge rates between 250-1300 kg/s and low- to moderate gas injection rates (yielding initial solids concentration of 15-70 vol%) channelized gas-particle mixture flows life-scaled to dense PDCs can be generated. The flow fronts of the currents reach velocities of up to 9.5 m/s over their first 12 m of travel and rapidly develop strong vertical density stratification. The PDCs typically form a highly mobile, <60 cm-thick dense and channel-confined underflow, with an overriding dilute and turbulent ash cloud surge that also laterally escapes the flume boundaries. Depending on the PDC starting conditions underflows with 1-45 vol% solids concentration are formed, while the upper surge contains <<1 vol.% solids. A characteristic feature of the underflow is the occurrence of 'ignitive' front breakouts, producing jetted lobes that accelerate outward from the flow front, initially forming a lobe-cleft structure, followed by segregation downslope into multiple flow pulses. Depending on initial solids concentration and discharge rate, stratified, dune-bedded and inversely graded bedforms are created whose thicknesses are remarkably uniform along the medial to distal runout path characterising highly mobile flow runout. Along with high-speed video footage we present time-series data of basal arrays of load- and gas-pore pressure transducers to characterise the mobile dense underflows. Data shows that the PDCs are comprised of a turbulent coarse-grained and air-ingesting front with particle-solids concentrations of 1-5 vol%. The front shows a brief phase of negative pore pressure due to the entrainment and upward elutriation of ambient air inside this front. It is immediately followed by the fine-ash rich and highly impermeable main flow body. Passage of the flow body is accompanied by strongly increasing pore-pressures of 1-3 kPa that almost fully supports the weight of the entire underflow - depicting flow-induced fluidisation of the main flow part. The remainder of the flow body shows further increases in pore-pressure aside with strong reductions in flow mass. This suggests the occurrence of zones of air-cushions forming at the base of the underflow that largely aid its inviscid runout. This sequence is repeated during arrival and passage of up to three more flow pulses. The low-permeability deposits maintain high internal gas pore pressures for several minutes after emplacement, before sudden deaeration, settling and gas loss is caused by fracturing. Flow-induced fluidisation and basal air-cushioning provide key processes behind the enigmatic long runout behaviour of dense PDCs.

The Use of the Visualisation of Multidimensional Data Using PCA to Evaluate Possibilities of the Division of Coal Samples Space Due to their Suitability for Fluidised Gasification

NASA Astrophysics Data System (ADS)

Jamróz, Dariusz; Niedoba, Tomasz; Surowiak, Agnieszka; Tumidajski, Tadeusz

2016-09-01

Methods serving to visualise multidimensional data through the transformation of multidimensional space into two-dimensional space, enable to present the multidimensional data on the computer screen. Thanks to this, qualitative analysis of this data can be performed in the most natural way for humans, through the sense of sight. An example of such a method of multidimensional data visualisation is PCA (principal component analysis) method. This method was used in this work to present and analyse a set of seven-dimensional data (selected seven properties) describing coal samples obtained from Janina and Wieczorek coal mines. Coal from these mines was previously subjected to separation by means of a laboratory ring jig, consisting of ten rings. With 5 layers of both types of coal (with 2 rings each) were obtained in this way. It was decided to check if the method of multidimensional data visualisation enables to divide the space of such divided samples into areas with different suitability for the fluidised gasification process. To that end, the card of technological suitability of coal was used (Sobolewski et al., 2012; 2013), in which key, relevant and additional parameters, having effect on the gasification process, were described. As a result of analyses, it was stated that effective determination of coal samples suitability for the on-surface gasification process in a fluidised reactor is possible. The PCA method enables the visualisation of the optimal subspace containing the set requirements concerning the properties of coals intended for this process.

On the hydration and conformation of cocaine in solution

NASA Astrophysics Data System (ADS)

Gillams, Richard J.; Lorenz, Christian D.; McLain, Sylvia E.

2017-05-01

In order to develop theories relating to the mechanism through which cocaine can diffuse across the blood-brain barrier, it is important to understand the interplay between the hydration of the molecule and the adopted conformation. Here key differences in the hydration of cocaine hydrochloride (CHC) and freebase cocaine (CFB) are highlighted on the atomic scale in solution, through the use of molecular dynamics simulations. By adopting different conformations, CHC and CFB experience differing hydration environments. The interplay between these two factors may account for the vast difference in solubility of these two molecules.

The THERMIE energy farm project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lange, H.J. de; Barbucci, P.; Greil, C.

1998-07-01

At a site close to Pisa (Italy), a plant with a net power-output of approximately 12 MWe will be erected; it features an atmospheric, air-blown, circulating fluidized-bed (CFB) gasifier, integrated with a 10.9 MWe, single-shaft, heavy-duty gas-turbine, suited to burn the low-calorific value fuel-gas produced by the gasifier, and a heat-recovery steam-generator (HRSG), which provides steam to a 5 MWe condensing steam-turbine. The plant's net thermal-efficiency amounts to about 32%. Wet wood is shredded to chips, mixed with the agricultural residues and fed to a dryer. Here, flue gases from the HRSG are used to dry the fuel to themore » desired moisture content. The dried fuel is gasified in a CFB reactor to produce a fuel-gas. This fuel-gas is cooled in two stages during which the gasification air is preheated and steam is produced in a gas-cooler (GC). Then, it is washed in a wet-scrubber and compressed in several intercooled stages before it is delivered to the gas turbine model PGT10 B/1. The gas turbine adopts a newly developed, high-efficiency air-compressor and its special, dual-fuel combustion-chamber is now under development. The combined-cycle is completed with a dual pressure-level HRSG. The steam turbine is fed by the steam produced in the HRSG and the GC located in the gasification island. As a consequence of the changed agricultural market, the fuel will consist not only of short rotation forestry (SRF) but also of forestry and agricultural residues. The wood species include poplar, black locust, willow and chestnut, whereas the agricultural residues comprise olive stones and grape-seed flour. The financial viability of the project relies on the incentive provided by the Italian government with a premium price per kWh of electricity produced from renewables and on the financial contribution from the EU.« less

The enrichment behavior of natural radionuclides in pulverized oil shale-fired power plants.

PubMed

Vaasma, Taavi; Kiisk, Madis; Meriste, Tõnis; Tkaczyk, Alan Henry

2014-12-01

The oil shale industry is the largest producer of NORM (Naturally Occurring Radioactive Material) waste in Estonia. Approximately 11-12 million tons of oil shale containing various amounts of natural radionuclides is burned annually in the Narva oil shale-fired power plants, which accounts for approximately 90% of Estonian electricity production. The radionuclide behavior characteristics change during the fuel combustion process, which redistributes the radionuclides between different ash fractions. Out of 24 operational boilers in the power plants, four use circulating fluidized bed (CFB) technology and twenty use pulverized fuel (PF) technology. Over the past decade, the PF boilers have been renovated, with the main objective to increase the efficiency of the filter systems. Between 2009 and 2012, electrostatic precipitators (ESP) in four PF energy blocks were replaced with novel integrated desulphurization technology (NID) for the efficient removal of fly ash and SO2 from flue gases. Using gamma spectrometry, activity concentrations and enrichment factors for the (238)U ((238)U, (226)Ra, (210)Pb) and (232)Th ((232)Th, (228)Ra) family radionuclides as well as (40)K were measured and analyzed in different PF boiler ash fractions. The radionuclide activity concentrations in the ash samples increased from the furnace toward the back end of the flue gas duct. The highest values in different PF boiler ash fractions were in the last field of the ESP and in the NID ash, where radionuclide enrichment factors were up to 4.2 and 3.3, respectively. The acquired and analyzed data on radionuclide activity concentrations in different PF boiler ashes (operating with an ESP and a NID system) compared to CFB boiler ashes provides an indication that changes in the fuel (oil shale) composition and boiler working parameters, as well as technological enhancements in Estonian oil shale fired power plants, have had a combined effect on the distribution patterns of natural radionuclides in the oil shale combustion products. Copyright © 2014 Elsevier Ltd. All rights reserved.

Hyporheic Microbial Biofilms as Indicators of Heavy and Rare Earth Metals in the Clark Fork Basin, Montana

NASA Astrophysics Data System (ADS)

Barnhart, E. P.; Hornberger, M.; Hwang, C.; Dror, I.; Bouskill, N.; Short, T.; Cain, D.; Fields, M. W.

2016-12-01

The ability to effectively monitor the impact of hard rock mining activities on rivers and streams is a growing concern given the large number of active and abandoned mines in the western United States. One such example, the Clark Fork Basin (CFB), western Montana, was extensively mined for copper in the early 20th century: it is now one of largest U.S. EPA superfund sites. Microbial biofilms are at the base of the lotic food chain and may provide a useful biomonitoring tool for the assessment of metal toxicity due to their environmental ubiquity, rapidity of response to environmental perturbation, and importance in determining metal mobility. Hyporheic microbial biofilms from the CFB were sampled in 2014, concurrent with the USGS National Research Programs (NRP) long-term site monitoring of metals in bed sediment and aquatic benthic insects. Integration of the DNA sequencing results from the hyporheic biofilms with the sediment and insect metal concentrations correlated several bacterial phyla with metal contamination. For example, the genus Lysobacter was strongly associated with copper (Cu) bioaccumulation in the aquatic insect Hydropsyche. These results support previous studies identifying Lysobacter as a bacterial genus that is resistant to Cu ions. Our analysis is the first to indicate that specific microorganisms can act as biomarkers of Cu contamination in rivers. Moreover, our work demonstrates that changes at the microbial community level in the hyporheic zone can be coupled to observed perturbations across higher trophic levels. In 2015, extensive remediation occurred at several of the sites sampled in 2014, providing an excellent opportunity to revisit the sites and examine the temporal variability of identified biomarkers and the short-term effectiveness of remediation. In addition, samples were analyzed for rare earth metals, of which little is known, and could provide additional insight into other metals that change the microbial community structure.

Inoculum Effects of Ceftobiprole, Daptomycin, Linezolid, and Vancomycin with Staphylococcus aureus and Streptococcus pneumoniae at Inocula of 105 and 107 CFU Injected into Opposite Thighs of Neutropenic Mice

PubMed Central

Lee, Dong-Gun; Murakami, Yoichi; Andes, David R.

2013-01-01

Reduced bactericidal efficacy at a high inoculum is known as the inoculum effect (IE). We used neutropenic mice to compare the IEs of ceftobiprole (CFB), daptomycin (DAP), linezolid (LZD), and vancomycin (VAN) against 6 to 9 strains of Staphylococcus aureus and 4 strains of Streptococcus pneumoniae at 2 inocula in opposite thighs of the same mice. Neutropenic mice had 104.5 to 105.7 CFU/thigh (low inoculum [LI]) in one thigh and 106.4 to 107.2 CFU/thigh (high inoculum [HI]) in the opposite thigh when treated for 24 h with subcutaneous (s.c.) doses every 12 h of DAP at 0.024 to 100 mg/kg of body weight and LZD at 0.313 to 320 mg/kg and s.c. doses every 6 h of CFB at 0.003 to 160 mg/kg and VAN at 0.049 to 800 mg/kg. Dose-response data were analyzed by a maximum effect (Emax) model using nonlinear regression. Static doses for each drug and at each inoculum were calculated, and the difference between HI and LI (IE index) gave the magnitude of IE for each drug-organism combination. Mean (range) IE indexes of S. aureus were 2.9 (1.7 to 4.6) for CFB, 4.1 (2.6 to 9.3) for DAP, 4.6 (1.7 to 7.1) for LZD, and 10.1 (6.3 to 20.3) for VAN. In S. pneumoniae, the IE indexes were 2.5 (1.3 to 3.3) for CFB, 2.0 (1.6 to 2.8) for DAP, 1.9 (1.7 to 2.2) for LZD, and 1.5 (0.8 to 3.2) for VAN; these values were similar for all drugs. In S. aureus, the IE was much larger with VAN than with CFB, DAM, and LZD (P < 0.05). An in vivo time course of vancomycin activity showed initiation of killing at 4- to 16-fold-higher doses at HI than at LI despite similar initial growth of controls. PMID:23295932

Early and Late Alkali Igneous Pulses and a High-3He Plume Origin for the Deccan Flood Basalts.

PubMed

Basu, A R; Renne, P R; Dasgupta, D K; Teichmann, F; Poreda, R J

1993-08-13

Several alkalic igneous complexes of nephelinite-carbonatite affinities occur in extensional zones around a region of high heat flow and positive gravity anomaly within the continental flood basalt (CFB) province of Deccan, India. Biotites from two of the complexes yield (40)Ar/(39)Ar dates of 68.53 +/- 0.16 and 68.57 +/- 0.08 million years. Biotite from a third complex, which intrudes the flood basalts, yields an (40)Ar/(39)Ar date of 64.96 +/- 0.1 1 million years. The complexes thus represent early and late magmatism with respect to the main pulse of CFB volcanism 65 million years ago. Rocks from the older complexes show a (3)He/(4)He ratio of 14.0 times the air ratio, an initial (87)Sr/(86)Sr ratio of 0.70483, and other geochemical characteristics similar to ocean island basalts; the later alkalic pulse shows isotopic evidence of crustal contamination. The data document 3.5 million years of incubation of a primitive, high-(3)He mantle plume before the rapid eruption of the Deccan CFB.

Flow Mapping in a Gas-Solid Riser via Computer Automated Radioactive Particle Tracking (CARPT)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Muthanna Al-Dahhan; Milorad P. Dudukovic; Satish Bhusarapu

2005-06-04

Statement of the Problem: Developing and disseminating a general and experimentally validated model for turbulent multiphase fluid dynamics suitable for engineering design purposes in industrial scale applications of riser reactors and pneumatic conveying, require collecting reliable data on solids trajectories, velocities ? averaged and instantaneous, solids holdup distribution and solids fluxes in the riser as a function of operating conditions. Such data are currently not available on the same system. Multiphase Fluid Dynamics Research Consortium (MFDRC) was established to address these issues on a chosen example of circulating fluidized bed (CFB) reactor, which is widely used in petroleum and chemicalmore » industry including coal combustion. This project addresses the problem of lacking reliable data to advance CFB technology. Project Objectives: The objective of this project is to advance the understanding of the solids flow pattern and mixing in a well-developed flow region of a gas-solid riser, operated at different gas flow rates and solids loading using the state-of-the-art non-intrusive measurements. This work creates an insight and reliable database for local solids fluid-dynamic quantities in a pilot-plant scale CFB, which can then be used to validate/develop phenomenological models for the riser. This study also attempts to provide benchmark data for validation of Computational Fluid Dynamic (CFD) codes and their current closures. Technical Approach: Non-Invasive Computer Automated Radioactive Particle Tracking (CARPT) technique provides complete Eulerian solids flow field (time average velocity map and various turbulence parameters such as the Reynolds stresses, turbulent kinetic energy, and eddy diffusivities). It also gives directly the Lagrangian information of solids flow and yields the true solids residence time distribution (RTD). Another radiation based technique, Computed Tomography (CT) yields detailed time averaged local holdup profiles at various planes. Together, these two techniques can provide the needed local solids flow dynamic information for the same setup under identical operating conditions, and the data obtained can be used as a benchmark for development, and refinement of the appropriate riser models. For the above reasons these two techniques were implemented in this study on a fully developed section of the riser. To derive the global mixing information in the riser, accurate solids RTD is needed and was obtained by monitoring the entry and exit of a single radioactive tracer. Other global parameters such as Cycle Time Distribution (CTD), overall solids holdup in the riser, solids recycle percentage at the bottom section of the riser were evaluated from different solids travel time distributions. Besides, to measure accurately and in-situ the overall solids mass flux, a novel method was applied.« less

Small boiler uses waste coal

DOE Office of Scientific and Technical Information (OSTI.GOV)

Virr, M.J.

Burning coal waste in small boilers at low emissions poses considerable problem. While larger boiler suppliers have successfully installed designs in the 40 to 80 MW range for some years, the author has been developing small automated fluid bed boiler plants for 25 years that can be applied in the range of 10,000 to 140,000 lbs/hr of steam. Development has centered on the use of an internally circulating fluid bed (CFB) boiler, which will burn waste fuels of most types. The boiler is based on the traditional D-shaped watertable boiler, with a new type of combustion chamber that enables amore » three-to-one turndown to be achieved. The boilers have all the advantages of low emissions of the large fluid boilers while offering a much lower height incorporated into the package boiler concept. Recent tests with a waste coal that had a high nitrogen content of 1.45% demonstrated a NOx emission below the federal limit of 0.6 lbs/mm Btu. Thus a NOx reduction on the order of 85% can be demonstrate by combustion modification alone. Further reductions can be made by using a selective non-catalytic reduction (SNCR) system and sulfur absorption of up to 90% retention is possible. The article describes the operation of a 30,000 lbs/hr boiler at the Fayette Thermal LLC plant. Spinheat has installed three ICFB boilers at a nursing home and a prison, which has been tested on poor-grade anthracite and bituminous coal. 2 figs.« less

Physical Properties of Granulates Used in Analogue Experiments of Caprock Failure and Sediment Remobilisation

NASA Astrophysics Data System (ADS)

Kukowski, N.; Warsitzka, M.; May, F.

2014-12-01

Geological systems consisting of a porous reservoir and a low-permeable caprock are prone to hydraulic fracturing, if pore pressure rises to the effective stress. Under certain conditions, hydraulic fracturing is associated with sediment remobilisation, e.g. sand injections or pipes, leading to reduced seal capacity of the caprock. In dynamically scaled analogue experiments using granular materials and air pressure, we intent to investigate strain patterns and deformation mechanisms during caprock failure and fluidisation of shallow over-pressured reservoirs. The aim of this study is to improve the understanding of leakage potential of a sealing formation and the fluidisation potential of a reservoir formation depending on rock properties and effective stress. For reliable interpretation of analogue experiments, physical properties of analogue materials, e.g. frictional strength, cohesion, density, permeability etc., have to be correctly scaled according to those of their natural equivalents. The simulation of caprock requires that the analogue material possess a low permeability and is capable to shear failure and tensional failure. In contrast, materials representing the reservoir have to possess high porosity and low shear strength. In order to find suitable analogue materials, we measured the stress-strain behaviour and the permeability of over 25 different types of natural and artificial granular materials, e.g. glass powder, siliceous microspheres, diatomite powder, loess, or plastic granulate. Here, we present data of frictional parameters, compressibility and permeability of these granular materials characterized as a function of sphericity, grain size, and density. The repertoire of different types of granulates facilitates the adjustment of accurate mechanical properties in the analogue experiments. Furthermore, conditions during seal failure and fluidisation can be examined depending on the wide range of varying physical properties.

Nutritional Quality and Price of Food Hampers Distributed by a Campus Food Bank: A Canadian Experience

PubMed Central

Abedi, Arvin; Wong, Alexander; Eslamian, Ghazaleh

2014-01-01

ABSTRACT Food insecurity is a mounting concern among Canadian post-secondary students. This study was conducted to evaluate the content of food hampers distributed by University of Alberta Campus Food Bank (CFB) and to assess the cost savings to students, using these hampers. Contents of hampers distributed among 1,857 students and their dependants since 2006 were evaluated against Canada's Food Guide (CFG) recommendations and Dietary Reference Intakes (DRI). Hampers were aimed at serving university students and one to five members of their households located in Edmonton, Western Canada. One thousand eight hundred fifty-seven clients in Alberta, Canada, were included in the study. Although all hampers provided adequate energy, their fat and animal protein contents were low. Compared to the CFG recommendations, the requirements of milk and alternatives and meat and alternatives were not sufficiently met for clients using ≥3-person hampers. None of food hampers (i.e. one- to five-person hampers) met the DRI recommendations for vitamin A and zinc. Clients of CFB received Canadian dollar (CN$) 14.88 to 64.3 worth of non-perishable food items in one- to five-person hampers respectively. Hampers provided from the CFB need improvement. Nutrients missing from the food hampers could be provided from fresh fruits, vegetables, dairy, and meat products; however, these foods are more expensive than processed food items. The CFB provides a significant amount of savings to its clients even without considering the additional perishable donations that are provided to clients. Interpretation of our data required the assumption that all clients were consuming all of their hampers, which may not always be the case. Clients that do not fully consume their hampers may benefit less from the food bank. PMID:25076666

Nutritional quality and price of food hampers distributed by a campus food bank: a Canadian experience.

PubMed

Jessri, Mahsa; Abedi, Arvin; Wong, Alexander; Eslamian, Ghazaleh

2014-06-01

Food insecurity is a mounting concern among Canadian post-secondary students. This study was conducted to evaluate the content of food hampers distributed by University of Alberta Campus Food Bank (CFB) and to assess the cost savings to students, using these hampers. Contents of hampers distributed among 1,857 students and their dependants since 2006 were evaluated against Canada's Food Guide (CFG) recommendations and Dietary Reference Intakes (DRI). Hampers were aimed at serving university students and one to five members of their households located in Edmonton, Western Canada. One thousand eight hundred fifty-seven clients in Alberta, Canada, were included in the study. Although all hampers provided adequate energy, their fat and animal protein contents were low. Compared to the CFG recommendations, the requirements of milk and alternatives and meat and alternatives were not sufficiently met for clients using > or = 3-person hampers. None of food hampers (i.e. one- to five-person hampers) met the DRI recommendations for vitamin A and zinc. Clients of CFB received Canadian dollar (CN$) 14.88 to 64.3 worth of non-perishable food items in one- to five-person hampers respectively. Hampers provided from the CFB need improvement. Nutrients missing from the food hampers could be provided from fresh fruits, vegetables, dairy, and meat products; however, these foods are more expensive than processed food items. The CFB provides a significant amount of savings to its clients even without considering the additional perishable donations that are provided to clients. Interpretation of our data required the assumption that all clients were consuming all of their hampers, which may not always be the case. Clients that do not fully consume their hampers may benefit less from the food bank.

A cross-ethnic survey of CFB and SLC44A4, Indian ulcerative colitis GWAS hits, underscores their potential role in disease susceptibility

PubMed Central

Gupta, Aditi; Juyal, Garima; Sood, Ajit; Midha, Vandana; Yamazaki, Keiko; Vich Vila, Arnau; Esaki, Motohiro; Matsui, Toshiyuki; Takahashi, Atsushi; Kubo, Michiaki; Weersma, Rinse K; Thelma, B K

2017-01-01

The first ever genome-wide association study (GWAS) of ulcerative colitis in genetically distinct north Indian population identified two novel genes namely CFB and SLC44A4. Considering their biological relevance, we investigated allelic/genetic heterogeneity in these genes among ulcerative colitis cohorts of north Indian, Japanese and Dutch origin using high-density ImmunoChip case–control genotype data. Comparative linkage disequilibrium profiling and test of association were performed. Of the 28 CFB SNPs, similar strength of association was observed for rs4151657 (novel ulcerative colitis GWAS SNP) in north Indians (P=1.73 × 10−10) and Japanese (P=2.02 × 10−12) but not in the Dutch. Further, a three-marker haplotype was shared between north Indians and Japanese (P<10−8), but a different five-marker haplotype was associated (P=2.07 × 10−6) in the Dutch. Of the 22 SLC44A4 SNPs, rs2736428 (novel ulcerative colitis GWAS SNP) was found significantly associated in north Indians (P=4.94 × 10−10) and Japanese (P=3.37 × 10−9), but not among the Dutch. These results suggest (i) apparent allelic heterogeneity in CFB and genetic heterogeneity in SLC44A4 across different ethnic groups; (ii) shared ulcerative colitis genetic etiological factors among Asians; and finally (iii) re-exploration of GWAS findings together with high-density genotyping/sequencing and trans-ethnic fine mapping approaches may help identify shared and population-specific risk variants and enable to explain missing disease heritability. PMID:27759029

Good Features to Correlate for Visual Tracking

NASA Astrophysics Data System (ADS)

Gundogdu, Erhan; Alatan, A. Aydin

2018-05-01

During the recent years, correlation filters have shown dominant and spectacular results for visual object tracking. The types of the features that are employed in these family of trackers significantly affect the performance of visual tracking. The ultimate goal is to utilize robust features invariant to any kind of appearance change of the object, while predicting the object location as properly as in the case of no appearance change. As the deep learning based methods have emerged, the study of learning features for specific tasks has accelerated. For instance, discriminative visual tracking methods based on deep architectures have been studied with promising performance. Nevertheless, correlation filter based (CFB) trackers confine themselves to use the pre-trained networks which are trained for object classification problem. To this end, in this manuscript the problem of learning deep fully convolutional features for the CFB visual tracking is formulated. In order to learn the proposed model, a novel and efficient backpropagation algorithm is presented based on the loss function of the network. The proposed learning framework enables the network model to be flexible for a custom design. Moreover, it alleviates the dependency on the network trained for classification. Extensive performance analysis shows the efficacy of the proposed custom design in the CFB tracking framework. By fine-tuning the convolutional parts of a state-of-the-art network and integrating this model to a CFB tracker, which is the top performing one of VOT2016, 18% increase is achieved in terms of expected average overlap, and tracking failures are decreased by 25%, while maintaining the superiority over the state-of-the-art methods in OTB-2013 and OTB-2015 tracking datasets.

Preparation of Orally Disintegrating Tablets Containing Powdered Tea Leaves with Enriched Levels of Bioactive Compounds by Means of Microwave Irradiation Technique.

PubMed

Tanaka, Hironori; Iwao, Yasunori; Izumikawa, Masahiro; Sano, Syusuke; Ishida, Hitoshi; Noguchi, Shuji; Itai, Shigeru

2016-01-01

In the present study, a microwave treatment process has been applied to prepare orally disintegrating tablets (ODTs) containing powdered tea leaves with enriched levels of the anti-inflammatory compounds such as chafuroside A (CFA) and chafuroside B (CFB). The use of distilled water as the adsorbed and granulation solvents in this preparation process afforded tablets with a long disintegration time (more than 120 s). The CFA and CFB contents of these tablets did not also change after 4 min of microwave irradiation due to the tablet temperature, which only increased to 100°C. In contrast, the tablet temperature increased up to 140°C after 3 min of microwave irradiation when a 1.68 M Na2HPO4 solution instead of distilled water. Notably, the disintegration time of these tablets was considerably improved (less than 20 s) compared with the microwave-untreated tablets, and there were 7- and 11-fold increases in their CFA and CFB contents. In addition, the operational conditions for the preparation of the tablets were optimized by face-centered composite design based on the following criteria: tablet hardness greater than 13 N, disintegration time less than 30 s and friability less than 0.5%. The requirements translated into X1 (the amount of granulation solvent), X2 (tableting pressure) and X3 (content of the powdered tea leaves) values of 45%, 0.43 kN and 32%, respectively, and the ODTs containing powdered tea leaves prepared under these optimized conditions were found to show excellent tablet properties and contain enriched levels of CFA and CFB.

High-Resolution Simulations of Gas-Solids Jet Penetration Into a High Density Riser Flow

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Tingwen

2011-05-01

High-resolution simulations of a gas-solids jet in a 0.3 m diameter and 15.9 m tall circulating fluidized bed (CFB) riser were conducted with the open source software-MFIX. In the numerical simulations, both gas and solids injected through a 1.6 cm diameter radial-directed tube 4.3 m above the bottom distributor were tracked as tracers, which enable the analysis of the characteristics of a two-phase jet. Two jetting gas velocities of 16.6 and 37.2 m/s were studied with the other operating conditions fixed. Reasonable flow hydrodynamics with respect to overall pressure drop, voidage, and solids velocity distributions were predicted. Due to themore » different dynamic responses of gas and particles to the crossflow, a significant separation of gas and solids within the jet region was predicted for both cases. In addition, the jet characteristics based on tracer concentration and tracer mass fraction profiles at different downstream levels are discussed. Overall, the numerical predictions compare favorably to the experimental measurements made at NETL.« less

The Application of Modern Powder Characterisation Methods in Product and Process Development of Solid Dosage Forms.

PubMed

Freeman, Tim; Brockbank, Katrina; Armstrong, Brian

2015-01-01

The pharmaceutical industry still produces the vast majority of their products, from powdered ingredients, in the form of solid doses. Despite their ubiquity, powders are difficult materials to characterise and understand, as evidenced by the frequent problems encountered during manufacture. The reason for this is their complex rheological behaviour coupled with numerous environmental variations, such as humidity. Equally, the range of processes used to manipulate powders subject them to extremes of stress from high compaction loads seen in compactors to the dispersed state seen in fluidised bed dryers. Thus, it is evident that ensuring that the powders characteristics are compatible with the way they are to be processed is a clear prerequisite for today's Quality by Design driven manufacturing. Modern, computer controlled instrumental techniques, including the dynamic, bulk and shear property measurements have enabled direct measurements of a powders response to aeration, consolidation and flow rate - all at low stresses - as well as quantifying shear and bulk properties (such as density, compressibility and permeability). In order to demonstrate how fully characterising a powder can be used in the design, operation and troubleshooting of processes, this paper will present examples of common pharmaceutical unit operations and the different powder characteristics that most influence the performance of each.

Dioxins and furans formation in pilot incineration tests of sewage sludge spiked with organic chlorine.

PubMed

Mininni, Giuseppe; Sbrilli, Andrea; Guerriero, Ettore; Rotatori, Mauro

2004-03-01

The factors affecting polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) formation were studied in sewage sludge incineration tests carried out on a demonstrative plant. The plant includes a circulating fluidised bed furnace (FBF) and a rotary kiln furnace (RKF), operating alternatively. During the tests sewage sludge was spiked with chlorinated hydrocarbons and the operating parameters of the afterburning chamber were varied. PCDD/F were sampled in each test before the bag filter, thus collecting the above contaminants before abatement systems. From the tests it appeared that PCDD/F were always produced in more abundance in the tests carried out by FBF than by RKF. The higher PCDD/F concentrations in the tests by FBF were reached when sewage sludge was spiked with a high dosage of a surrogate organic mixture of chlorinated hydrocarbons and when the afterburning chamber was used only as transit equipment with the burner off. The distribution of the different PCDD/F homologues was compared. P5CDFs were generally the prevalent fraction, with very few exceptions for the tests by RKF at high temperature of the afterburning chamber. As for FBF tests, it was found that the PCDD/F homologue profile depends on the afterburning chamber temperature.

Discriminant analysis of the metabolic effects of a new combined contraceptive vaginal ring containing Nestorone/EE vs. a second-generation oral contraceptive containing levonorgestrel/EE.

PubMed

Rad, Mandana; Burggraaf, Jacobus; de Kam, Marieke L; Cohen, Adam F; Kluft, Cornelis

2012-09-01

Discriminant analysis (DA) was performed on data of two combined hormonal contraceptives (CHC) differing in estrogen ratio to explore whether a combination of variables rather than a single variable distinguishes CHCs better. Data were used of a parallel study in premenopausal women treated for three cycles (21 days on, 7 days off) with a contraceptive vaginal ring delivering Nestorone and ethinyl estradiol (EE) or an oral contraceptive containing levonorgestrel and EE. DA was performed on the change from baseline (CFB) and the end-of-treatment values at 3 months for lipids, sex-hormone binding globulin (SHBG), C-reactive protein, angiotensinogen, blood pressure and hemostasis variables, and on the hemostasis variables only. For the complete set, the CFB for factor VII (FVII), SHBG and plasminogen (PLG), or end-of-treatment SHBG- and FVII level discriminated the treatments best. Maximal discrimination for the hemostasis data was by CFB for FVII and PLG or end-of-treatment FVII level. DA identifies differences between CHCs and may provide information on the factors associated with thrombotic risk. Copyright © 2012 Elsevier Inc. All rights reserved.

A mitochondrial-like aconitase in the bacterium Bacteroides fragilis: implications for the evolution of the mitochondrial Krebs cycle.

PubMed

Baughn, Anthony D; Malamy, Michael H

2002-04-02

Aconitase and isocitrate dehydrogenase (IDH) enzyme activities were detected in anaerobically prepared cell extracts of the obligate anaerobe Bacteroides fragilis. The aconitase gene was located upstream of the genes encoding the other two components of the oxidative branch of the Krebs cycle, IDH and citrate synthase. Mutational analysis indicates that these genes are cotranscribed. A nonpolar in-frame deletion of the acnA gene that encodes the aconitase prevented growth in glucose minimal medium unless heme or succinate was added to the medium. These results imply that B. fragilis has two pathways for alpha-ketoglutarate biosynthesis-one from isocitrate and the other from succinate. Homology searches indicated that the B. fragilis aconitase is most closely related to aconitases of two other Cytophaga-Flavobacterium-Bacteroides (CFB) group bacteria, Cytophaga hutchinsonii and Fibrobacter succinogenes. Phylogenetic analysis indicates that the CFB group aconitases are most closely related to mitochondrial aconitases. In addition, the IDH of C. hutchinsonii was found to be most closely related to the mitochondrial/cytosolic IDH-2 group of eukaryotic organisms. These data suggest a common origin for these Krebs cycle enzymes in mitochondria and CFB group bacteria.

CFH haplotypes and ARMS2, C2, C3, and CFB alleles show association with susceptibility to age-related macular degeneration in Mexicans

PubMed Central

Zenteno, Juan Carlos; Fernández-López, Juan Carlos; Rodríguez-Corona, Ulises; Falfán-Valencia, Ramcés; Sebastian, Leticia; Morales, Fabiola; Ochoa-Contreras, Daniel; Carnevale, Alessandra; Silva-Zolezzi, Irma

2014-01-01

Purpose To evaluate the contribution of genetic variants of complement factor H (CFH), complement component 2 and 3 (C2 and C3), complement factor B (CFB), and age-related maculopathy susceptibility 2 (ARMS2) to age-related macular degeneration (AMD) risk in the Mexican Mestizo population. Methods Analysis included 282 unrelated Mexican patients with advanced AMD, 205 healthy controls, and 280 population controls. Stereoscopic fundus images were graded on the Clinical Age-Related Maculopathy System (CARMS). We designed a resequencing strategy using primers with M13 adaptor for the 23 exons of the CFH gene in a subgroup of 96 individuals clinically evaluated: 48 AMD cases and 48 age- and sex-matched healthy controls. Single nucleotide polymorphisms (SNPs) in C3 (Arg80Gly and Pro292Leu), C2 (rs547154), CFB (Leu9His), and ARMS2 (Ala69Ser) were genotyped in all patients, healthy and population controls using TaqMan assay. Results All evaluated individuals were Mexican Mestizos, and their genetic ancestry was validated using 224 ancestry informative markers and calculating Fst values. The CFH resequencing revealed 19 SNPs and a common variant in the intron 2 splice acceptor site; three CFH haplotypes inferred from individual genotypes, showed significant differences between cases and controls. The risk alleles in C3 (rs1047286, odds ratio [OR]=2.48, 95% confidence interval [CI]=1.64–3.75, p=1.59E-05; rs2230199, OR=2.15, 95% CI=1.48–3.13, p=6.28E-05) and in ARMS2 (rs10490924, OR=3.09, 95% CI=2.48–3.86, p=5.42E-23) were strongly associated with risk of AMD. The protective effect of alleles in C2 (rs547154) and CFB (rs4151667) showed a trend but was not significantly associated after correction for multiple testing. Conclusions Our results show that ARMS2 and C3 are major contributors to advanced AMD in Mexican patients, while the contributions of CFH, C2, and CFB are minor to those of other populations, reveling significant ethnic differences in minor allele frequencies. We provide evidence that two specific common haplotypes in the CFH gene predispose individuals to AMD, while another may confer reduced risk of disease in this admixed population. PMID:24453474

Reactions homogenes en phase gazeuse dans les lits fluidises

NASA Astrophysics Data System (ADS)

Laviolette, Jean-Philippe

This thesis presents a study on homogeneous gas-phase reactions in fluidized beds. The main objective is to develop new tools to model and characterize homogeneous gas-phase reactions in this type of reactor. In the first part of this work, the non-premixed combustion of C 1 to C4 n-alkanes with air was investigated inside a bubbling fluidized bed of inert sand particles at intermediate temperatures: 923 K ≤ TB ≤ 1123 K. For ethane, propane and n-butane, combustion occurred mainly in the freeboard region at bed temperatures below T1 = 923 K. On the other hand, complete conversion occurred within 0.2 m of the injector at: T2 = 1073 K. For methane, the measured values of T1 and T2 were significantly higher at 1023 K and above 1123 K, respectively. The fluidized bed combustion was accurately modeled with first-order global kinetics and two one-phase PFR models in series: one PFR to model the region close to the injector and another to represent the main fluidized bed body. The measured global reaction rates for C2 to C4 n-alkanes were characterized by a uniform Arrhenius expression, while the global reaction rate for methane was significantly slower. Reactions in the injector region either led to significant conversion in that zone or an autoignition delay inside the main fluidized bed body. The conversion in the injector region increased with rising fluidized bed temperature and decreased with increasing jet velocity. To account for the promoting and inhibiting effects, an analogy was made with the concept of induction time: the PFR length (bi) of the injector region was correlated to the fluidized bed temperature and jet velocity using an Arrhenius expression. In the second part of this work, propane combustion experiments were conducted in the freeboard of a fluidized bed of sand particles at temperatures between 818 K and 923 K and at superficial gas velocity twice the minimum fluidization velocity. The freeboard region was characterized by simultaneous measurements of solids flux, chemical composition, temperature and pressure. Autoignition was only recorded within 0.06 m of the bed surface at temperatures greater than 833 K. Propane conversion predicted by six different microkinetic mechanistic models were compared to the experimental measurements: all six models underestimated the reaction rate above the bed surface. However, accounting for the production of H2O2 during in-bed combustion significantly increased the calculated reaction rates and resulted in a better agreement between predicted and measured propane conversion. In the third part of this work, a novel spectroscopic method was developed to measure quantitatively and simultaneously solids volume fraction (1-epsilon) and gaseous species composition (Yi) in a gas/solid system. The method was comprised of an FT-IR coupled to a fibre-optic probe that could perform real-time and in-situ measurements of absorbance. The effect of (1-epsilon) and Yi on the absorbance spectra were additive and could be independently calibrated. Experiments were conducted with alkane/nitrogen mixtures and two types of particles: sand and FCC. Fuel mole fractions and (1-epsilon) were varied between 1.8 - 10.1 mol% and 0 - 0.45, respectively. The relative errors for Yi time-averaged measurements were below 6% and the error increased significantly with decreasing beam intensity. A proof of concept for a novel application in fluidized beds was also completed: the fibre-optic probe was used to measure the molar fraction of a tracer gas inside the emulsion and bubble phases during gas tracer experiments. (Abstract shortened by UMI.)

Extending Correlation Filter-Based Visual Tracking by Tree-Structured Ensemble and Spatial Windowing.

PubMed

Gundogdu, Erhan; Ozkan, Huseyin; Alatan, A Aydin

2017-11-01

Correlation filters have been successfully used in visual tracking due to their modeling power and computational efficiency. However, the state-of-the-art correlation filter-based (CFB) tracking algorithms tend to quickly discard the previous poses of the target, since they consider only a single filter in their models. On the contrary, our approach is to register multiple CFB trackers for previous poses and exploit the registered knowledge when an appearance change occurs. To this end, we propose a novel tracking algorithm [of complexity O(D) ] based on a large ensemble of CFB trackers. The ensemble [of size O(2 D ) ] is organized over a binary tree (depth D ), and learns the target appearance subspaces such that each constituent tracker becomes an expert of a certain appearance. During tracking, the proposed algorithm combines only the appearance-aware relevant experts to produce boosted tracking decisions. Additionally, we propose a versatile spatial windowing technique to enhance the individual expert trackers. For this purpose, spatial windows are learned for target objects as well as the correlation filters and then the windowed regions are processed for more robust correlations. In our extensive experiments on benchmark datasets, we achieve a substantial performance increase by using the proposed tracking algorithm together with the spatial windowing.

The 40Ar/39Ar age record and geodynamic significance of Indo-Madagascar and Deccan flood basalt volcanism in the Sarnu-Dandali alkaline complex, Rajasthan, northwestern India

NASA Astrophysics Data System (ADS)

Vijayan, Anjali; Pande, Kanchan; Sheth, Hetu; Kant Sharma, Kamal

2017-04-01

The Sarnu-Dandali alkaline complex in Rajasthan, northwestern India, is considered to represent early, pre-tholeiite magmatism in the Deccan Traps continental flood basalt (CFB) province, based on a single 40Ar/39Ar age of 68.57 Ma. Rhyolites found in the complex are considered to be 750 Ma Malani basement. Our new 40Ar/39Ar ages of 88.9-86.8 Ma (for syenites, nephelinite, phonolite and rhyolite) and 66.3 ± 0.4 Ma (2σ, melanephelinite) provide clear evidence that whereas the Sarnu-Dandali complex has Deccan-age components, it is dominantly an older (by ˜20 million years) alkaline complex, with rhyolites included. Sarnu-Dandali is thus an alkaline igneous center active at least twice in the Late Cretaceous, and also much before as suggested by a basalt flow underlying the Early Cretaceous Sarnu Sandstone. The 89-86 Ma 40Ar/39Ar ages fully overlap with those for the Indo-Madagascar CFB province formed during continental break-up between India (plus Seychelles) and Madagascar. Recent 40Ar/39Ar work has shown polychronous emplacement (over ≥ 45 million years) of the Mundwara alkaline complex in Rajasthan, 100 km from Sarnu-Dandali, and 84-80 Ma ages obtained from Mundwara also arguably represent late stages of the Indo-Madagascar CFB volcanism. Remnants of the Indo-Madagascar CFB province are known from several localities in southern India but hitherto unknown from northwestern India 2000 km away. Additional equivalents buried under the vast Deccan Traps are highly likely. We relate the Sarnu-Dandali and Mundwara complexes to decompression melting of ancient, subduction-fluxed, enriched mantle lithosphere due to periodic lithospheric extension during much of the Cretaceous, and hundreds of kilometers inland from the India-Madagascar and India-Seychelles rifted margins.

Origin and hydrology of a large, intact Early Cambrian paleocave system and its role in overlying fluidisation structures, Arctic Canada

NASA Astrophysics Data System (ADS)

Mathieu, Jordan; Turner, Elizabeth C.; Rainbird, Robert H.

2017-04-01

Paleokarst is most commonly expressed as subtle stratigraphic surfaces rather than large void systems penetrating deeply into the paleo-subsurface. In contrast, a regional Precambrian-Cambrian unconformity on Victoria Island (NWT, Canada), is associated with exceptional exposure of large, intact Cambrian paleocaverns (100 m diameter; tens of m high). The paleocaves are distributed along a paleo-horizontal plane, and an associated gryke network is present in the 30-60 m of Neoproterozoic dolostone between cave rooves and the base of overlying Cambrian sandstone; both are filled by Cambrian sandstone. The formation and preservation of such karst features require aggressive dissolution along a stable paleo-water-table shortly before transgression and deposition of shallow-marine sand over the dolostone. During the transgression, the karst network acted as a conduit for flowing groundwater that was discharged through overlying, unconsolidated Cambrian shallow-marine sand, producing water-escape structures (sand volcanoes and their conduits). The conduits are preserved as cylindrical remnants of the sand volcanoes' feeder pipes. Sediment fluidisation was probably caused by variations in the hydraulic-head gradient in a meteoric lens near the Cambrian coastline under a tropical climate with abundant, probably seasonally variable rainfall that caused pulses in subsurface fluid flow. Spatial distribution of the paleocaves and sand volcanoes suggests their formation on the southeast side of a recently faulted horst of Proterozoic carbonate bedrock that formed a nearshore island during early Cambrian sea-level rise. Fluidisation structures such as those reported here have generally been difficult to interpret owing to a lack of data on the fluid hydraulics of the underlying aquifer. This is the first report linking the hydraulics of a well-characterised paleokarst to development of fluid-escape structures. Such structures are widely known from sandstones overlying the sub-Cambrian unconformity around the circumference of Laurentia.

Study of cluster behavior in the riser of CFB by the DSMC method

NASA Astrophysics Data System (ADS)

Liu, H. P.; Liu, D. Y.; Liu, H.

2010-03-01

The flow behaviors of clusters in the riser of a two-dimensional (2D) circulating fluidized bed was numerically studied based on the Euler-Lagrangian approach. Gas turbulence was modeled by means of Large Eddy Simulation (LES). Particle collision was modeled by means of the direct simulation Monte Carlo (DSMC) method. Clusters' hydrodynamic characteristics are obtained using a cluster identification method proposed by sharrma et al. (2000). The descending clusters near the wall region and the up- and down-flowing clusters in the core were studied separately due to their different flow behaviors. The effects of superficial gas velocity on the cluster behavior were analyzed. Simulated results showed that near wall clusters flow downward and the descent velocity is about -45 cm/s. The occurrence frequency of the up-flowing cluster is higher than that of down-flowing cluster in the core of riser. With the increase of superficial gas velocity, the solid concentration and occurrence frequency of clusters decrease, while the cluster axial velocity increase. Simulated results were in agreement with experimental data. The stochastic method used in present paper is feasible for predicting the cluster flow behavior in CFBs.

Improved refractory performance through partnership

DOE Office of Scientific and Technical Information (OSTI.GOV)

Linck, F.E.; Peters, D.

1995-12-31

From the early designs and construction of Circulating Fluidized Bed (CFB) boilers, many improvements have been made based upon observations of performance. Included in these improvements have been the refractory linings. The early refractory linings were subjected to extreme fluctuations in temperatures as the units experienced up and down conditions. As the designs were improved refractory failures were mostly due to the operating conditions and other mechanical stresses rather than continual shutdowns and startups. More recent problems observed with refractory linings are localized areas of high erosion, corrosion and cracking which result in hot spots and eventual shutdowns for repair.more » Today the objective of refractory suppliers and installers is to strive towards planned shutdowns rather than emergency shutdowns. This can be accomplished through partnerships between operations, material suppliers and installers. In essence, the concept is a cooperative effort between these groups to solve the variety of refractory problems in order to achieve longer refractory lining performance and less chance for emergency shutdowns. The reliability of the refractory lining is dependent on the successful combination of the material selected, proper design and the installation of the refractory material. Where these three elements combine, the lining has the best chance of performing its intended purpose.« less

Assessment of Pb-slag, MSWI bottom ash and boiler and fly ash for using as a fine aggregate in cement mortar.

PubMed

Saikia, Nabajyoti; Cornelis, Geert; Mertens, Gilles; Elsen, Jan; Van Balen, Koenraad; Van Gerven, Tom; Vandecasteele, Carlo

2008-06-15

Three types of wastes, metallurgical slag from Pb production (SLG), the sand-sized (0.1-2 mm) fraction of MSWI bottom ash from a grate furnace (SF), and boiler and fly ash from a fluidised bed incinerator (BFA), were characterized and used to replace the fine aggregate during preparation of cement mortar. The chemical and mineralogical behaviour of these wastes along with the reactivities of the wastes with lime and the hydration behaviour of ordinary Portland cement paste with and without these wastes added were evaluated by various chemical and instrumental techniques. The compressive strengths of the cement mortars containing waste as a partial substitution of fine aggregates were also assessed. Finally, leaching studies of the wastes and waste containing cement mortars were conducted. SLG addition does not show any adverse affect during the hydration of cement, or on the compressive strengths behaviours of mortars. Formation of expansive products like ettringite, aluminium hydroxide and H2 gas due to the reaction of some constituents of BFA and SF with alkali creates some cracks in the paste as well as in the cement mortars, which lower the compressive strength of the cement mortars. However, utilization of all materials in cement-based application significantly improves the leaching behaviour of the majority of the toxic elements compared to the waste as such.

Development of a Two-fluid Drag Law for Clustered Particles using Direct Numerical Simulation and Validation through Experiments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gokaltun, Seckin; Munroe, Norman; Subramaniam, Shankar

2014-12-31

This study presents a new drag model, based on the cohesive inter-particle forces, implemented in the MFIX code. This new drag model combines an existing standard model in MFIX with a particle-based drag model based on a switching principle. Switches between the models in the computational domain occur where strong particle-to-particle cohesion potential is detected. Three versions of the new model were obtained by using one standard drag model in each version. Later, performance of each version was compared against available experimental data for a fluidized bed, published in the literature and used extensively by other researchers for validation purposes.more » In our analysis of the results, we first observed that standard models used in this research were incapable of producing closely matching results. Then, we showed for a simple case that a threshold is needed to be set on the solid volume fraction. This modification was applied to avoid non-physical results for the clustering predictions, when governing equation of the solid granular temperate was solved. Later, we used our hybrid technique and observed the capability of our approach in improving the numerical results significantly; however, improvement of the results depended on the threshold of the cohesive index, which was used in the switching procedure. Our results showed that small values of the threshold for the cohesive index could result in significant reduction of the computational error for all the versions of the proposed drag model. In addition, we redesigned an existing circulating fluidized bed (CFB) test facility in order to create validation cases for clustering regime of Geldart A type particles.« less

Neural network-based system for pattern recognition through a fiber optic bundle

NASA Astrophysics Data System (ADS)

Gamo-Aranda, Javier; Rodriguez-Horche, Paloma; Merchan-Palacios, Miguel; Rosales-Herrera, Pablo; Rodriguez, M.

2001-04-01

A neural network based system to identify images transmitted through a Coherent Fiber-optic Bundle (CFB) is presented. Patterns are generated in a computer, displayed on a Spatial Light Modulator, imaged onto the input face of the CFB, and recovered optically by a CCD sensor array for further processing. Input and output optical subsystems were designed and used to that end. The recognition step of the transmitted patterns is made by a powerful, widely-used, neural network simulator running on the control PC. A complete PC-based interface was developed to control the different tasks involved in the system. An optical analysis of the system capabilities was carried out prior to performing the recognition step. Several neural network topologies were tested, and the corresponding numerical results are also presented and discussed.

IEEE 802.11e EDCF performance evaluation

NASA Astrophysics Data System (ADS)

Huang, Benxiong; Zhang, Fan; Wang, Yan; Wang, Xiaoling

2004-04-01

This paper evaluates the performances of the contention-based channel access mechanism of IEEE 802.11e, called enhanced distributed coordination function (EDCF), compared with the 802.11 legacy MAC in supporting voice, video and data applications through network simulation of a scenario of 802.11e. Then we discuss the effects of Contention Window (CW) and Arbitration Inter-Frame Space (AIFS) on service differentiation and total throughput. We also consider an optional feature of the EDCF, called contention-free burst (CFB). Through our simulation study, we can draw a conclusion that the EDCF with TXOP can provide better-differentiated channel access for different traffic types than EDCF without TXOP especially at high traffic load conditions. But the movements caused by the parameters in CFB seem a lot bouncing and instability when in different application and configuration.

Unraveling sorption of lead in aqueous solutions by chemically modified biochar derived from coconut fiber: A microscopic and spectroscopic investigation.

PubMed

Wu, Weidong; Li, Jianhong; Lan, Tian; Müller, Karin; Niazi, Nabeel Khan; Chen, Xin; Xu, Song; Zheng, Lirong; Chu, Yingchao; Li, Jianwu; Yuan, Guodong; Wang, Hailong

2017-01-15

In this study, we examined the efficacy of nine different types of coconut-fiber derived biochars (CFBs), prepared at different temperatures and chemically modified with ammonia, hydrogen peroxide and nitric acid, to remove lead (Pb 2+ ) from aqueous solutions. Langmuir-q m values of the biochars pyrolyzed at 300°C and modified with ammonia and nitric acid increased from 49.5 to 105.5 and 85.2mgg -1 , respectively, compared to control (unmodified), whereas hydrogen peroxide treatment had no effect. The maximum amount of Pb adsorbed on biochars was in the order of CFB-700>MCFB-300-NH 3 ·H 2 O>CFB-500>MCFB-300-HNO 3 >CFB-300. X-ray absorption fine structure (XAFS) spectroscopy results revealed that Pb-montmorillonite, Pb(C 2 H 3 O 2 ) 2 , PbSO 4 , Pb-Al 2 O 3 and Pb 3 (PO 4 ) 2 were the five most important Pb species observed in Pb-loaded biochars, and as such, favoring Pb immobilization in aqueous solutions. Overall, the sorption capacity of CFBs pyrolyzed at 300°C substantially increased for Pb 2+ with ammonia and nitric acid modification. However, these chemical modifications did not improve the sorption of Pb on CFBs pyrolyzed at temperatures ≥500°C, thereby highlighting a temperature dependent response of chemically modified biochars to Pb sorption in this study. Copyright © 2016 Elsevier B.V. All rights reserved.

3D Numerical Prediction of Gas-Solid Flow Behavior in CFB Risers for Geldart A and B Particles

NASA Astrophysics Data System (ADS)

Özel, A.; Fede, P.; Simonin, O.

In this study, mono-disperse flows in squared risers conducted with A and B-type particles were simulated by Eulerian n-fluid 3D unsteady code. Two transport equations developed in the frame of kinetic theory of granular media supplemented by the interstitial fluid effect and the interaction with the turbulence (Balzer et al., 1996) are resolved to model the effect of velocity fluctuations and inter-particle collisions on the dispersed phase hydrodynamic. The studied flow geometries are three-dimensional vertical cold channels excluding cyclone, tampon and returning pipe of a typical circulating fluidized bed. For both type of particles, parametric studies were carried out to determine influences of boundary conditions, physical parameters and turbulence modeling. The grid dependency was analyzed with mesh refinement in horizontal and axial directions. For B-type particles, the results are in good qualitative agreement with the experiments and numerical predictions are slightly improved by the mesh refinement. On the contrary, the simulations with A-type particles show a less satisfactory agreement with available measurements and are highly sensitive to mesh refinement. Further studies are carried out to improve the A-type particles by modeling subgrid-scale effects in the frame of large-eddy simulation approach.

Characteristics and reactivity of rapidly hydrated sorbent for semidry flue gas desulfurization.

PubMed

Zhang, Jie; You, Changfu; Zhao, Suwei; Chen, Changhe; Qi, Haiying

2008-03-01

Semidry flue gas desulfurization with a rapidly hydrated sorbent was studied in a pilot-scale circulating fluidized bed (CFB) experimental facility. The desulfurization efficiency was measured for various operating parameters, including the sorbent recirculation rate and the water spray method. The experimental results show that the desulfurization efficiencies of the rapidly hydrated sorbent were 1.5-3.0 times higher than a commonly used industrial sorbent for calcium to sulfur molar ratios from 1.2 to 3.0, mainly due to the higher specific surface area and pore volume. The Ca(OH)2 content in the cyclone separator ash was about 2.9% for the rapidly hydrated sorbent and was about 0.1% for the commonly used industrial sorbent, due to the different adhesion between the fine Ca(OH)2 particles and the fly ash particles, and the low cyclone separation efficiency for the fine Ca(OH)2 particles that fell off the sorbent particles. Therefore the actual recirculation rates of the active sorbent with Ca(OH)2 particles were higher for the rapidly hydrated sorbent, which also contributed to the higher desulfurization efficiency. The high fly ash content in the rapidly hydrated sorbent resulted in good operating stability. The desulfurization efficiency with upstream water spray was 10-15% higher than that with downstream water spray.

In-plane magnetic anisotropy and coercive field dependence upon thickness of CoFeB

NASA Astrophysics Data System (ADS)

Kipgen, Lalminthang; Fulara, Himanshu; Raju, M.; Chaudhary, Sujeet

2012-09-01

The structural and magnetic properties of as-grown 5-50 nm thin ion-beam sputter deposited transition metal-metalloid Co20Fe60B20 (CFB) films are reported in this communication. A broad peak observed at 2θ∼45° in the glancing angle X-ray diffraction pattern revealed the formation of very fine nano-sized grains embedded in majority amorphous CFB matrix. Although no magnetic field is applied during deposition, the longitudinal magneto-optic Kerr effect measurements performed at 300 K in these as-grown films clearly established the presence of in-plane uniaxial magnetic anisotropy (Ku). It is argued that this observed anisotropy is strain-induced. This is supported by the observed dependence of direction of Ku on the angle between applied magnetic field and crystallographic orientation of the underlying Si(100) substrate, and increase in the coercivity with the increase of the film thickness.

Complement factor H is expressed in adipose tissue in association with insulin resistance.

PubMed

Moreno-Navarrete, José María; Martínez-Barricarte, Rubén; Catalán, Victoria; Sabater, Mònica; Gómez-Ambrosi, Javier; Ortega, Francisco José; Ricart, Wifredo; Blüher, Mathias; Frühbeck, Gema; Rodríguez de Cordoba, Santiago; Fernández-Real, José Manuel

2010-01-01

Activation of the alternative pathway of the complement system, in which factor H (fH; complement fH [CFH]) is a key regulatory component, has been suggested as a link between obesity and metabolic disorders. Our objective was to study the associations between circulating and adipose tissue gene expressions of CFH and complement factor B (fB; CFB) with obesity and insulin resistance. Circulating fH and fB were determined by enzyme-linked immunosorbent assay in 398 subjects. CFH and CFB gene expressions were evaluated in 76 adipose tissue samples, in isolated adipocytes, and in stromovascular cells (SVC) (n = 13). The effects of weight loss and rosiglitazone were investigated in independent cohorts. Both circulating fH and fB were associated positively with BMI, waist circumference, triglycerides, and inflammatory parameters and negatively with insulin sensitivity and HDL cholesterol. For the first time, CFH gene expression was detected in human adipose tissue (significantly increased in subcutaneous compared with omental fat). CFH gene expression in omental fat was significantly associated with insulin resistance. In contrast, CFB gene expression was significantly increased in omental fat but also in association with fasting glucose and triglycerides. The SVC fraction was responsible for these differences, although isolated adipocytes also expressed fB and fH at low levels. Both weight loss and rosiglitazone led to significantly decreased circulating fB and fH levels. Increased circulating fH and fB concentrations in subjects with altered glucose tolerance could reflect increased SVC-induced activation of the alternative pathway of complement in omental adipose tissue linked to insulin resistance and metabolic disturbances.

The Effect of State Competitive Food and Beverage Regulations on Childhood Overweight and Obesity.

PubMed

Datar, Ashlesha; Nicosia, Nancy

2017-05-01

Policy efforts for combating childhood obesity have sought stronger state policies for regulating competitive foods and beverages (CF&Bs) available in schools. However, the evidence linking state policies to children's overall diet and body weight outcomes is limited and mixed, and experts have called for more rigorous studies that are able to address concerns about selection bias. The present study leverages a rare natural experiment where children in military families are "assigned" to different state policies, due to their military parent's periodic relocation, to examine whether state CF&B policies were associated with children's body mass index (BMI) and overweight or obesity. We analyzed data from 894 children (12-13 years old) in army families attending public schools located near 25 installations across 23 states in 2013. State CF&B policy measures from the Bridging the Gap project were linked to the child data. Primary outcomes included BMI z-scores and indicator for overweight or obesity. For a subsample of children with self-reported food frequency measures, we also examined the link between state CF&B policies and overall diet. All regression analyses adjusted for a rich set of child and family covariates. Having strong or weak policies was significantly associated with lower BMI z-scores, lower odds of overweight or obesity, and better dietary outcomes, relative to no policy. A portfolio of policies that includes multiple strong policies is likely needed to observe any meaningful changes in BMI and obesity. Copyright © 2016 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Environmental effects of magmatic sulfur emitted by large-scale flood basalt eruptions

NASA Astrophysics Data System (ADS)

Schmidt, A.; Skeffington, R.; Thordarson, T.; Self, S.; Forster, P.; Rap, A.; Ridgwell, A.; Fowler, D.; Wilson, M.; Mann, G.; Wignall, P.; Carslaw, K. S.

2015-12-01

Continental flood basalt (CFB) volcanism has been temporally, and therefore causally, linked to periods of environmental crisis in the past 260 Ma. The majority of the proposed causal relationships are, however, qualitative, in particular the potential climatic and environmental effects of large amounts of sulfur dioxide (SO2) emitted to the atmosphere. CFB provinces are typically formed by numerous individual eruptions, each lasting years to decades, with highly uncertain periods of quiescence lasting hundreds to thousands of years. I will present results obtained from a global aerosol-climate model set-up to simulate the sulfur-induced climatic and environmental effects of individual decade to century-long CFB eruptions. For sulfur dioxide emissions representative of a single decade-long eruption in the 65 Ma Deccan Trap Volcanic Province, the model predicts a substantial reduction in global surface temperature of 4.5 K, which is in good agreement with multi-proxy palaeo-temperature records. However, the calculated cooling is short-lived and temperatures recover within less than 50 years once volcanic activity ceases. In contrast to previous studies, I show that acid rain from decade-long eruptions cannot cause widespread vegetation stress or loss due to the buffering capacities of soils. The direct exposure of vegetation to acid mists and fogs, however, could cause damage where the exposure is high and sustained, such as at high elevations. Finally, I will use these modeling results to place constraints on the likely environmental effects and habitability by simulating different eruption frequencies and durations as well as hiatus periods and by comparing to the proxy records.

Association between CFH, CFB, ARMS2, SERPINF1, VEGFR1 and VEGF polymorphisms and anatomical and functional response to ranibizumab treatment in neovascular age-related macular degeneration.

PubMed

Cobos, Estefania; Recalde, Sergio; Anter, Jaouad; Hernandez-Sanchez, Maria; Barreales, Carla; Olavarrieta, Leticia; Valverde, Alicia; Suarez-Figueroa, Marta; Cruz, Fernando; Abraldes, Maximino; Pérez-Pérez, Julian; Fernández-Robredo, Patricia; Arias, Luis; García-Layana, Alfredo

2018-03-01

We sought to determine if specific genetic single nucleotide polymorphisms (SNPs) influence vascular endothelial growth factor inhibition response to ranibizumab in neovascular age-related macular degeneration (AMD). A total of 403 Caucasian patients diagnosed with exudative AMD were included. After a three-injection loading phase, a pro re nata regimen was followed. Nine SNPs from six different genes (CFH, CFB, ARMS2, SERPINF1, VEGFR1, VEGF) were genotyped. Non-genetic risk factors (gender, smoking habit and hypertension) were also assessed. Patients were classified as good or poor responders (GR or PR) according to functional (visual acuity), anatomical (foveal thickness measured by OCT) and fluid criteria (fluid/no fluid measured by OCT). Hypertension was the environmental factor with the strongest poor response association with ranibizumab in the anatomical measure after the loading phase (p = 0.0004; OR 3.7; 95% CI, 2.4-5.8) and after 12 months of treatment (p = 10 -5 ; OR 2.3; 95% CI, 1.5-3.4). The genetic variants rs12614 (CFB), rs699947 (VEGFA) and rs7993418 (VEGFR1) predisposed patients to a good response, while rs12603486 and rs1136287 (SERPINF1) were associated with a poor response. The protective genotype of rs800292 variant (CFH) was also associated with a poor anatomical response (p 0.0048). All these data suggest that genetics play an important role in treatment response in AMD patients. © 2017 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Modelling of Specimen Fracture

DTIC Science & Technology

2013-09-23

for information and evaluation purposes only. Any commercial use including use for manufacture is prohibited. © Her Majesty the Queen in Right of...Christopher Bayley DRDC Atlantic Dockyard Laboratory Pacific CFB Esquimalt, Building 199 PO Box 17000, Station Forces Victoria , British Columbia Canada

Lithostratigraphy and structure of the early Archaean Doolena Gap Greenstone Belt, East Pilbara Terrane (EPT), Western Australia

NASA Astrophysics Data System (ADS)

Wiemer, D.; Schrank, C. E.; Murphy, D. T.

2014-12-01

We present a detailed lithostratigraphic and structural analysis of the Archean Doolena Gap greenstone belt to shed light on the tectonic evolution of the EPT. The study area is divided into four structural domains: i) marginal orthogneisses of the MGC (Muccan Granitoid Complex), ii) a dominantly mafic mylonitic shear zone (South Muccan Shear Zone, SMSZ) enveloping the MGC, iii) a Central Fold Belt of dominantly mafic greenschists (CFB), and iv) a lower greenschist- to sub-greenschist southern domain. Toward the dome margin, abrupt increases in deformation intensity occur across domain boundaries. Domain boundaries and intra-domain shear zones are marked by significant carbonate +/- quartz alteration and high-strain non-coaxial deformation with dome-up kinematics. The southern domain comprises pillow basalts of the Mount Ada Formation (MAF), conformably overlain by clastic sediments and minor pillow basalts of the Duffer Formation (DF). The MAF and DF are overlain by an up to 1km thick package of quartzite (Strelley Pool Formation) across an angular unconformity. Isoclinal folds (F2) within the CFB to the North deform an early foliation (S1) within dominantly mafic schists and associated carbonate veins. F2 folds are preserved within lozenges that are parallel to the axial planes of F2 folds in a regional E-W trending foliation (S2) and to the SMSZ. Lozenges are often bound by zones of significant carbonate alteration. The lozenges are folded recumbently (F3), with sub-vertical fold axes pointing towards the dome. The F3 axes are parallel to mineral stretching lineations on S2 indicating dome-up movement. The entire belt is cut by late NE-SW-striking faults that exhibit dominantly brittle deformation in the southern domain but ductile drag folding (F4) in the CFB. Therefore, the southern domain must have overlain the CFB during this D4 event. We propose a protracted structural history of the greenstone belt where successive deformation events relate to the episodic emplacement of the MGC. We demonstrate that the greenstone keel is mainly characterised by an anastomosing shear zone network, induced by hydro-chemical weakening of mafic schists. This implies that previous estimates of stratigraphic thickness are significantly overestimated.

Complement Factor H Is Expressed in Adipose Tissue in Association With Insulin Resistance

PubMed Central

Moreno-Navarrete, José María; Martínez-Barricarte, Rubén; Catalán, Victoria; Sabater, Mònica; Gómez-Ambrosi, Javier; Ortega, Francisco José; Ricart, Wifredo; Blüher, Mathias; Frühbeck, Gema; Rodríguez de Cordoba, Santiago; Fernández-Real, José Manuel

2010-01-01

OBJECTIVE Activation of the alternative pathway of the complement system, in which factor H (fH; complement fH [CFH]) is a key regulatory component, has been suggested as a link between obesity and metabolic disorders. Our objective was to study the associations between circulating and adipose tissue gene expressions of CFH and complement factor B (fB; CFB) with obesity and insulin resistance. RESEARCH DESIGN AND METHODS Circulating fH and fB were determined by enzyme-linked immunosorbent assay in 398 subjects. CFH and CFB gene expressions were evaluated in 76 adipose tissue samples, in isolated adipocytes, and in stromovascular cells (SVC) (n = 13). The effects of weight loss and rosiglitazone were investigated in independent cohorts. RESULTS Both circulating fH and fB were associated positively with BMI, waist circumference, triglycerides, and inflammatory parameters and negatively with insulin sensitivity and HDL cholesterol. For the first time, CFH gene expression was detected in human adipose tissue (significantly increased in subcutaneous compared with omental fat). CFH gene expression in omental fat was significantly associated with insulin resistance. In contrast, CFB gene expression was significantly increased in omental fat but also in association with fasting glucose and triglycerides. The SVC fraction was responsible for these differences, although isolated adipocytes also expressed fB and fH at low levels. Both weight loss and rosiglitazone led to significantly decreased circulating fB and fH levels. CONCLUSIONS Increased circulating fH and fB concentrations in subjects with altered glucose tolerance could reflect increased SVC-induced activation of the alternative pathway of complement in omental adipose tissue linked to insulin resistance and metabolic disturbances. PMID:19833879

Petropower energia project under way in Chile promises refiner better economics at lower cost

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1996-12-31

Construction of the Republic of Chile`s first public/private industrial partnership project is well under way. Ground was broken for the $232-million Petropower Energia Limitada project early this year, shortly after the final contract between the parties - Foster Wheeler Power Systems, Inc. (FWPS); Petrox S.A. Refineria de Petroleo and Empresa Nacional del Petroleo (ENAP) - was signed. The Petropower project, located adjacent to Petrox`s 84,000-b/d refinery in Talcahuano, represents the first project ever to combine petroleum coking technology with cogeneration technology in a single project financing. Petropower is 85% owned by FWPS, 7.5% by ENAP, the Chilean national oil companymore » and parent of Petrox S.A. When completed in mid-1998, the Petropower project will enable Petrox to refine heavier crudes and enhance the refinery`s flexibility and economics. The project will consist of a delayed coking facility (a 12,000-b/d delayed coking unit and a 7,000-b/d hydrotreating plant) and a 67-MW (59 MW net) cogeneration plant. The coke produced will fuel a Foster Wheeler proprietary-design circulating fluidized-bed (CFB) boiler which will generate all the high-pressure steam and electric power needs of the Petrox refinery. This unit will be the first circulating fluidized-bed boiler to be built in Latin America. The cogeneration facility, using limestone as a reagent and equipped with a baghouse, will control SO{sub x} emissions from combustion of the green coke fuel and easily meet all Chilean environmental standards. Moreover, by constructing the cogeneration facility, Petrox will not have to proceed with capital improvements to existing facilities to ensure a reliable source of steam and electricity, resulting in substantial savings for Petrox. The cogeneration plant provides a permanent {open_quotes}disposal{close_quotes} for all coke produced by the delayed coker, thereby solving any future problems of unwanted or excess coke.« less

Experimental investigation of ash deposits on convection heating surfaces of a circulating fluidized bed municipal solid waste incinerator.

PubMed

Tang, Zhi; Chen, Xiaoping; Liu, Daoyin; Zhuang, Yaming; Ye, Minghua; Sheng, Hongchan; Xu, Shaojuan

2016-10-01

Incineration of municipal solid waste (MSW) is a waste treatment method which can be sustainable in terms of waste volume reduction, as well as a source of renewable energy. During MSW combustion, increased formation of deposits on convection heating exchanger surfaces can pose severe operational problems, such as fouling, slagging and corrosion. These problems can cause lower heat transfer efficiency from the hot flue gas to the working fluid inside the tubes. A study was performed where experiments were carried out to examine the ash deposition characteristics in a full-scale MSW circulating fluidized bed (CFB) incinerator, using a newly designed deposit probe that was fitted with six thermocouples and four removable half rings. The influence of probe exposure time and probe surface temperature (500, 560, and 700°C) on ash deposit formation rate was investigated. The results indicate that the deposition mass and collection efficiency achieve a minimum at the probe surface temperature of 560°C. Ash particles are deposited on both the windward and leeward sides of the probe by impacting and thermophoretic/condensation behavior. The major inorganic elements present in the ash deposits are Ca, Al and Si. Compared to ash deposits formed on the leeward side of the probe, windward-side ash deposits contain relatively higher Ca and S concentrations, but lower levels of Al and Si. Among all cases at different surface temperatures, the differences in elemental composition of the ash deposits from the leeward side are insignificant. However, as the surface temperature increases, the concentrations of Al, Si, K and Na in the windward-side ash deposits increase, but the Ca concentration is reduced. Finally, governing mechanisms are proposed on the basis of the experimental data, such as deposit morphology, elemental composition and thermodynamic calculations. Copyright © 2016. Published by Elsevier B.V.

A targeted proteomic strategy for the measurement of oral cancer candidate biomarkers in human saliva

PubMed Central

Kawahara, Rebeca; Bollinger, James G.; Rivera, César; Ribeiro, Ana Carolina P.; Brandão, Thaís Bianca; Paes Leme, Adriana F.; MacCoss, Michael J.

2015-01-01

Head and neck cancers, including oral squamous cell carcinoma (OSCC), are the sixth most common malignancy in the world and are characterized by poor prognosis and a low survival rate. Saliva is oral fluid with intimate contact with OSCC. Besides non-invasive, simple, and rapid to collect, saliva is a potential source of biomarkers. In this study, we build an SRM assay that targets fourteen OSCC candidate biomarker proteins, which were evaluated in a set of clinically-derived saliva samples. Using Skyline software package, we demonstrated a statistically significant higher abundance of the C1R, LCN2, SLPI, FAM49B, TAGLN2, CFB, C3, C4B, LRG1, SERPINA1 candidate biomarkers in the saliva of OSCC patients. Furthermore, our study also demonstrated that CFB, C3, C4B, SERPINA1 and LRG1 are associated with the risk of developing OSCC. Overall, this study successfully used targeted proteomics to measure in saliva a panel of biomarker candidates for OSCC. PMID:26552850

A regularization of the Burgers equation using a filtered convective velocity

NASA Astrophysics Data System (ADS)

Norgard, Greg; Mohseni, Kamran

2008-08-01

This paper examines the properties of a regularization of the Burgers equation in one and multiple dimensions using a filtered convective velocity, which we have dubbed as the convectively filtered Burgers (CFB) equation. A physical motivation behind the filtering technique is presented. An existence and uniqueness theorem for multiple dimensions and a general class of filters is proven. Multiple invariants of motion are found for the CFB equation which are shown to be shared with the viscous and inviscid Burgers equations. Traveling wave solutions are found for a general class of filters and are shown to converge to weak solutions of the inviscid Burgers equation with the correct wave speed. Numerical simulations are conducted in 1D and 2D cases where the shock behavior, shock thickness and kinetic energy decay are examined. Energy spectra are also examined and are shown to be related to the smoothness of the solutions. This approach is presented with the hope of being extended to shock regularization of compressible Euler equations.

Anaerobic co-digestion of sewage sludge and food waste.

PubMed

Prabhu, Meghanath S; Mutnuri, Srikanth

2016-04-01

Anaerobic co-digestion of organic matter improves digester operating characteristics and its performance. In the present work, food waste was collected from the institute cafeteria. Two types of sludge (before centrifuge and after centrifuge) were collected from the fluidised bed reactor of the institute treating sewage wastewater. Food waste and sludge were studied for their physico-chemical characteristics, such as pH, chemical oxygen demand, total solids, volatile solids, ammoniacal nitrogen, and total nitrogen. A biomethane potential assay was carried out to find out the optimum mixing ratio of food waste and sludge for anaerobic co-digestion. Results indicated that food waste mixed with sludge in the ratio of 1:2 produced the maximum biogas of 823 ml gVS(-1)(21 days) with an average methane content of 60%. Batch studies were conducted in 5 L lab-glass reactors at a mesophilic temperature. The effect of different substrate loading rates on biogas production was investigated. The mixing ratio of food waste and sludge was 1:2. A loading rate of 1 gVS L d(-1)gave the maximum biogas production of 742 ml g(-1)VS L d(-1)with a methane content of 50%, followed by 2 gVS L d(-1)with biogas of 539 ml g(-1)VS L d(-1) Microbial diversity of the reactor during fed batch studies was investigated by terminal restriction fragment length polymorphism. A pilot-scale co-digestion of food waste and sludge (before centrifuge) indicated the process stability of anaerobic digestion. © The Author(s) 2016.

The effect of riser end geometry on gas-solid hydrodynamics in a CFB riser operating in the core annular and dilute homogeneous flow regimes

DOE PAGES

Breault, Ronald W.; Monazam, Esmail R.; Shadle, Lawrence J.; ...

2017-02-12

Riser hydrodynamics are a function of the flow rates of gas and solids as well as the exit geometry, particularly when operated above the upper transport velocity. This work compares the exit voidage for multiple geometries and two different solids: Geldart group A glass beads and Geldart group B coke. Geometries were changed by modifying the volume of an abrupt T-shaped exit above the lateral riser exit. This was accomplished by positioning a plunger at various heights above the exit from zero to 0.38 m. A dimensionless expression used to predict smooth exit voidage was modified to account for themore » effect of the depth of the blind-T. The new correlation contains the solids-gas load ratio, solids-to-gas density ratio, bed-to-particle diameter ratio, gas Reynolds Number, as well as a term for the exit geometry. This study also found that there was a minimum riser roof height above the blind-T exit beyond which the riser exit voidage was not affected by the exit geometry. A correlation for this minimum riser roof height has also been developed in this study. This study covered riser superficial gas velocities of 4.35 to 7.7 m/s and solids circulation rates of 1.3 to 11.5 kg/s.« less

Production, quality and quality assurance of Refuse Derived Fuels (RDFs).

PubMed

Sarc, R; Lorber, K E

2013-09-01

This contribution describes characterization, classification, production, application and quality assurance of Refuse Derived Fuels (RDFs) that are increasingly used in a wide range of co-incineration plants. It is shown in this paper, that the fuel-parameter, i.e. net calorific value [MJ/kg(OS)], particle size d(90) or d(95) [mm], impurities [w%], chlorine content [w%], sulfur content [w%], fluorine content [w%], ash content [w%], moisture [w%] and heavy metals content [mg/kg(DM)], can be preferentially used for the classification of different types of RDF applied for co-incineration and substitution of fossil-fuel in different industial sectors. Describing the external production of RDF by processing and confectioning of wastes as well as internal processing of waste at the incineration plant, a case study is reported on the application of RDF made out of different household waste fractions in a 120,000t/yr Waste to Energy (WtE) circulating fluidized bed (CFB) incinerator. For that purpose, delivered wastes, as well as incinerator feedstock material (i.e. after internal waste processing) are extensively investigated. Starting with elaboration of sampling plan in accordance with the relevant guidelines and standards, waste from different suppliers was sampled. Moreover, manual sorting analyses and chemical analyses were carried out. Finally, results of investigations are presented and discussed in the paper. Copyright © 2013 Elsevier Ltd. All rights reserved.

Application of sorption technique for decontamination of liquid radwaste and natural water from cesium and strontium radionuclides

DOE Office of Scientific and Technical Information (OSTI.GOV)

Milyutin, V.V.; Gelis, V.M.; Penzin, R.A.

1995-12-31

In this paper the results obtained in field tests of decontaminating radioactive natural and industrial solutions of different chemical and radionuclide composition from cesium and strontium radionuclides are reported. Decontamination of industrial reservoir water at the Production Association Mayak (Chelyabinsk Region, Russia) was performed using CMP synthetic zeolite. Efficient decontamination of the feed water is achieved after preliminary precipitation of hardness salts in the form of carbonates. Decontamination of water from the pool for spent fuel element storage from {sup 137}Cs was conducted using NGA ferricyanide sorbent. Decontamination factors with respect to {sup 137}Cs of 400 have been reached, themore » installation throughput being 100,000 by (bed volumes). Decontamination of liquid radwaste at Murmansk Shipping Co was conducted with CFB, CMP synthetic zeolites and NGA ferricyanide sorbent as well. Decontamination of D and D solutions and wastes of the special laundry resulted in decontamination factors within the range of 20--400, 10--100, and 10--30 with respect to {sup 137}Cs, {sup 90}Sr, and total {beta}-activity, respectively. Installation throughput of 3,000--5,000 bv for zeolites and 8,000--10,000 bv for ferrocyanide sorbents has been reached. Results obtained prove the high efficiency of sorption technique for decontaminating solutions from cesium and strontium radionuclides.« less

Modelling the Fracture Behavior of a 350WT Steel

DTIC Science & Technology

2014-05-01

May 2014 © Her Majesty the Queen in Right of Canada, as represented by the Minister of National Defence, 2014 © Sa...Christopher Bayley DRDC Atlantic Dockyard Laboratory Pacific CFB Esquimalt, Building 199 PO Box 17000, Station Forces Victoria , British Columbia Canada V9A

Discriminating between pyroxenite and peridotite sources for continental flood basalts (CFB) in southern Africa using olivine chemistry

NASA Astrophysics Data System (ADS)

Howarth, Geoffrey H.; Harris, Chris

2017-10-01

Continental Flood Basalts (CFB) result from voluminous outpourings of magma that often precede continental break-up. Notwithstanding the petrogenetic importance of CFBs, the nature of the mantle source for such magmas is contentious, particularly with regard to picrites with Ni-rich olivine phenocrysts. Previous studies have suggested that Ni-rich olivines associated with plume volcanism in regions of thickened (>90 km) lithosphere are related to either source mineralogy differences (peridotite versus pyroxenite) or change in olivine-melt partitioning due to pressure increase. In order to evaluate these two hypotheses, we present trace element data for olivines from the Karoo CFB Tuli and Mwenezi picrites and the Etendeka CFB Horingbaai/LTZ-L type picrites, all of which erupted in regions of thickened (>90 km) lithosphere in southern Africa. Karoo picrite olivines are Ni-rich, Ca- and Mn-poor, and have low (<1.4) 100*Mn/Fe. These compositions are consistent with a pyroxenitic source. Etendeka Horingbaai/LTZ-L picrite olivines do not show Ni-enrichment, but are characterized by high Al and Cr, and high (>1.4) 100*Mn/Fe, which is more consistent with high temperature melting of a dominantly peridotitic source. We also show that the Karoo and Etendeka olivines are characterized by distinct Mn/Zn ratios of <13 and >15, respectively. In addition, bulk rock geochemical data compilations and previously reported olivine δ18O for Karoo and Etendeka CFBs are discussed in order to further constrain source components based on previously described pyroxenite melt geochemical indices such as MgO-CaO systematics, FeO/MnO, Zn/Fe, and FC3MS (FeO/CaO-3*MgO/SiO2). These geochemical indices suggest a pyroxenite-dominated source for Karoo CFBs as well as for Etendeka ferropicrites whereas a peridotite-dominated source is indicated for Etendeka Horingbaai/LTZ-L type picrites analyzed in this study. Based on our data, Ni-enrichment of olivine in plume-related magmas in regions of thickened lithosphere in southern Africa is not ubiquitous. We therefore suggest that mineralogical variation of the source is a more likely major control of olivine chemistry and parent melt variations for Karoo and Etendeka CFBs. We also show that olivine Mn-Zn correlations are a useful discriminator for source variation and recommend the use of olivine Mn /Zn < 13 for a pyroxenite-dominated source relative to olivine Mn /Zn > 15 for a peridotite-dominated source.

Enigmatic organosiliceous rocks in the 2000 Ma petrified oil field in Russian Fennoscandia

NASA Astrophysics Data System (ADS)

Deines, Yu.; Melezhik, V.; Lepland, A.; Filippov, M.; Romashkin, A.; Rychanchik, D.

2009-04-01

The c. 2000 Ma, 900 m-thick, Zaonezhskaja Formation in the Onega basin, Russian Fennoscandia, contains one of the greatest accumulations of organic matter (OM) in the Early Precambrian. It also represents a unique preservation of a supergiant petrified oil field. Zaonezhskaja Formation rocks are greenschist-facies volcaniclastic greywackes (distal turbidites), dolostone and limestones, mafic tuffs and lavas intruded by numerous mafic sills. Several sedimentary beds are enriched in OM with the overall content of total organic carbon (TOC) ranging from 0.1 to 16 wt.% whereas d13C varies between -44 and -17 per mil(V-PDB). The formation contains plentiful evidence of generation and migration of oil (now petrified) as well as oil traps. Results of geophysical surveys combined with drillcore data, including results recently obtained within the framework of the Fennoscandian Arctic Russia - Drilling Early Earth Project (FAR-DEEP), revealed numerous bodies of organosiliceous rocks (OSR) containing mainly silica (c. 57 wt.% SiO2), organic carbon (up to 40 wt.%), Al2O3 (c. 5 wt.%), S (c. 2 wt.%), and minor K, Mg, Fe, Ca and Ti. d13C of the OSR ranges between -40 and -20 per mil. The OSR form crudely stratified beds, cupola-like bodies or veins. The cupola-like bodies show cross-cutting (intrusive) contacts with the host turbiditic greywackes, reach thicknesses of 120 m with a lateral extent of several hundreds of metres. Veins are a few tens of centimetres thick. The OSR show close spatial association with gabbro sills. Although different fabrics have been recognised in the OSR, syngenetic macro- and microbreccias per se are the most common rock types. Fragments of different sedimentary rocks, as well as those with alternating C-rich and C-poor concentric lamina are present. The latter suggests precipitation from hydrothermal fluids. The nature of the OSR remains enigmatic. Several models have been advanced for explanation of origin of the OSR. However, neither of them could explain the source, and joint transport of two major components, namely silica and OM. We propose a model involving a hydrothermal system initiated by heat produced during the emplacement of numerous mafic intrusive bodies. Such heat may have created the necessary temperature gradient for earlier oil generation, thermal oil to gas cracking, and initiation of shallow-seated, sub-surface, hydrothermal circulation. The proposed result would have been the mingling of silica leached from mafic rocks with hydrocarbon, and gas (primarily CO2, CH4) extracted from the host sedimentary rocks. Such a gas-rich C-Si-H2O substance would have migrated into permeable beds. A high sedimentation rate, as expected in many turbiditic depositional environments, would have produced a high lithostatic pressure on to unlithified beds during the course of the basin subsidence. This would have forced gas-rich C-Si-H2O fluids that moved either laterally along permeable beds or vertically along zones of weakness. In the first case, sediments 'impregnated' with gas-rich C-Si-H2O fluids would have formed stratigraphic beds of OSR, whereas in the second case the result would been crosscutting veins. Beds may retain some primary layering, whereas veins do not. If veins reached the seafloor, the sediment - C-Si-H2O mush would have extruded in the form of a mud volcano / hydrothermal mound, and thus formed a cupola-like morphology. During the course of compression, the sediment - C-Si-H2O mush might have experienced several stages of partial lithification, as well as fluidisation processes leading to the formation of several generations of micro- and macro-brecciated rocks. The large d13C range of reduced carbon in the OSR suggests a complex maturation process of the biogenic OM. Further detailed microstructural, geochemical, isotopic and biomarker studies are planned for distinguishing between biological and abiological processes involved in the formation of the enigmatic OSR.

Spring-Based Helmet System Support Prototype to Address Aircrew Neck Strain

DTIC Science & Technology

2014-06-01

Helicopter Squadron stationed at CFB Borden ALSE Personnel Flight Engineers Pilots 4.6 Discussion of Verification Results 4.6.1 Reduce the mass on the...the participant in the pilot’s posture. Figure 8. A simulation of Flight Engineers’ postures during landing and low flying maneuvres. Figure 9

Polaribacter gen. nov., with three new species, P. irgensii sp. nov., P. franzmannii sp. nov. and P. filamentus sp. nov., gas vacuolate polar marine bacteria of the Cytophaga-Flavobacterium-Bacteroides group and reclassification of 'Flectobacillus glomeratus' as Polaribacter glomeratus comb. nov

NASA Technical Reports Server (NTRS)

Gosink, J. J.; Woese, C. R.; Staley, J. T.

1998-01-01

Several psychrophilic, gas vacuolate strains of the Cytophage-Flavobacterium-Bacteroides (CFB) phylogenetic group were isolated from sea ice and water from the Arctic and the Antarctic. The closest taxonomically defined species by 16S rRNA sequence analysis is 'Flectobacillus glomeratus'. However, 'Flc. glomeratus' is phylogenetically distant from the Flectobacillus type species, Flc. major. On the basis of phenotypic, genotypic and 16S rRNA sequence analyses we propose a new genus, Polaribacter, with three new species, Polaribacter irgensii strain 23-P (ATCC 700398), Polaribacter franzmannii strain 301 (ATCC 700399) and Polaribacter filamentus strain 215 (ATCC 700397). P. filamentus is the type species of the genus. None of these species exhibits a cosmopolitan or bipolar distribution. This is the first taxonomic description of gas vacuolate bacteria in the CFB group. Additionally, we propose that 'Flc. glomeratus' be reclassified to the genus Polaribacter as P. glomeratus, comb. nov.

A prospective observational study of techniques to remove corneal foreign body in the emergency department.

PubMed

Quirke, Michael; Mullarkey, Caitriona; Askoorum, Shakti; Coffey, Norma; Binchy, James

2014-06-01

Patients  with corneal foreign bodies (CFBs) often present to the emergency department (ED). However, removal techniques vary among emergency physicians (EPs). A prospective, single-blinded, observational study was performed to compare slit-lamp-aided (SLA) versus non-slit-lamp-aided (NSLA) CFB removal by EPs. Five EPs enrolled consecutive patients with a CFB over 3 months. One blinded EP reviewed patients after 3 days. The study end points were: change in visual acuity; visual analogue pain scale (VAS) score at 12 and 24 h; satisfaction rating; symptoms at follow-up; and rate of complications. 54 patients were enrolled: 28 had SLA removal and 26 NSLA removal; 52 were male; 22 had undergone previous CFB removal; six were wearing eye protection at the time of injury. Forty-three patients were reviewed: 26 by attendance and 18 by telephone. There was no difference in any end points at review. However, patients in the SLA group had median VAS scores that were 1.5 cm lower after 24 h than patients in the NSLA group (p=0.43, 95% CI -2.0 to 1.0). One patient in the SLA group developed keratitis. We show that patient satisfaction ratings, complications and visual acuity were similar for the two methods. There was a trend for increased pain in the NSLA group at 12 and 24 h. Slit-lamp biomicroscopy and the use of magnification to remove CFBs remains the gold standard of care, and more intensive training should be given to EPs at the departmental level, particularly in EDs that receive patients with eye injuries. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Optimising the in vitro and in vivo performance of oral cocrystal formulations via spray coating.

PubMed

Serrano, Dolores R; Walsh, David; O'Connell, Peter; Mugheirbi, Naila A; Worku, Zelalem Ayenew; Bolas-Fernandez, Francisco; Galiana, Carolina; Dea-Ayuela, Maria Auxiliadora; Healy, Anne Marie

2018-03-01

Engineering of pharmaceutical cocrystals is an advantageous alternative to salt formation for improving the aqueous solubility of hydrophobic drugs. Although, spray drying is a well-established scale-up technique in the production of cocrystals, several issues can arise such as sublimation or stickiness due to low glass transition temperatures of some organic molecules, making the process very challenging. Even though, fluidised bed spray coating has been successfully employed in the production of amorphous drug-coated particles, to the best of our knowledge, it has never been employed in the production of cocrystals. The feasibility of this technique was proven using three model cocrystals: sulfadimidine (SDM)/4-aminosalicylic acid (4ASA), sulfadimidine/nicotinic acid (NA) and ibuprofen (IBU)/ nicotinamide (NAM). Design of experiments were performed to understand the critical formulation and process parameters that determine the formation of either cocrystal or coamorphous systems for SDM/4ASA. The amount and type of binder played a key role in the overall solid state and in vitro performance characteristics of the cocrystals. The optimal balance between high loading efficiencies and high degree of crystallinity was achieved only when a binder: cocrystal weight ratio of 5:95 or 10:90 was used. The cocrystal coated beads showed an improved in vitro-in vivo performance characterised by: (i) no tendency to aggregate in aqueous media compared to spray dried formulations, (ii) enhanced in vitro activity (1.8-fold greater) against S. aureus, (iii) larger oral absorption and bioavailability (2.2-fold higher C max ), (iv) greater flow properties and (v) improved chemical stability than cocrystals produced by other methods derived from the morphology and solid nature of the starter cores. Copyright © 2017 Elsevier B.V. All rights reserved.

Comparison of ash behavior of different fuels in fluidised bed combustion using advanced fuel analysis and global equilibrium calculations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zevenhoven-Onderwater, M.; Blomquist, J.P.; Skrifvars, B.J.

1999-07-01

The behavior of different ashes is predicted by means of a combination of an advanced fuel analysis and global equilibrium calculations. In order to cover a broad spectrum of fuels a coal, a peat, a forest residue and Salix (i.e. willow) are studied. The latter was taken with and without soil contamination, i.e. with a high and low content of silica , respectively. It is shown that mineral matter in fossil and biomass fuels can be present in the matrix of the fuel itself or as included minerals. Using an advanced fuel analysis, i.e. a fractionation method, this mineral contentmore » can be divided into four fractions. The first fraction mainly contains those metal ions, that can be leached out of the fuel by water and mainly contains alkali sulfates, carbonates and chlorides. The second fraction mainly consists of those ions leached out by ammonium acetate and covers those ions, that are connected to the organic matrix. The third fraction contains the metals leached out by hydrochloric acid and contains earth alkali carbonates and sulfates as well as pyrites. The rest fraction contains those minerals, that are not leached out by any of the above mentioned solvents, such as silicates. A global equilibrium analysis is used to predict the thermal and chemical behavior of the combined first and second fractions and of the combined third and rest fractions under pressurized and/or atmospheric combustion conditions. Results of both the fuel analysis and the global equilibrium analysis are discussed and practical implications for combustion processes are pointed out.« less

Variability of single bean coffee volatile compounds of Arabica and robusta roasted coffees analysed by SPME-GC-MS.

PubMed

Caporaso, Nicola; Whitworth, Martin B; Cui, Chenhao; Fisk, Ian D

2018-06-01

We report on the analysis of volatile compounds by SPME-GC-MS for individual roasted coffee beans. The aim was to understand the relative abundance and variability of volatile compounds between individual roasted coffee beans at constant roasting conditions. Twenty-five batches of Arabica and robusta species were sampled from 13 countries, and 10 single coffee beans randomly selected from each batch were individually roasted in a fluidised-bed roaster at 210 °C for 3 min. High variability (CV = 14.0-53.3%) of 50 volatile compounds in roasted coffee was obtained within batches (10 beans per batch). Phenols and heterocyclic nitrogen compounds generally had higher intra-batch variation, while ketones were the most uniform compounds (CV < 20%). The variation between batches was much higher, with the CV ranging from 15.6 to 179.3%. The highest variation was observed for 2,3-butanediol, 3-ethylpyridine and hexanal. It was also possible to build classification models based on geographical origin, obtaining 99.5% and 90.8% accuracy using LDA or MLR classifiers respectively, and classification between Arabica and robusta beans. These results give further insight into natural variation of coffee aroma and could be used to obtain higher quality and more consistent final products. Our results suggest that coffee volatile concentration is also influenced by other factors than simply the roasting degree, especially green coffee composition, which is in turn influenced by the coffee species, geographical origin, ripening stage and pre- and post-harvest processing. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Design of Experiments to Study the Impact of Process Parameters on Droplet Size and Development of Non-Invasive Imaging Techniques in Tablet Coating

PubMed Central

Dennison, Thomas J.; Smith, Julian; Hofmann, Michael P.; Bland, Charlotte E.; Badhan, Raj K.; Al-Khattawi, Ali; Mohammed, Afzal R.

2016-01-01

Atomisation of an aqueous solution for tablet film coating is a complex process with multiple factors determining droplet formation and properties. The importance of droplet size for an efficient process and a high quality final product has been noted in the literature, with smaller droplets reported to produce smoother, more homogenous coatings whilst simultaneously avoiding the risk of damage through over-wetting of the tablet core. In this work the effect of droplet size on tablet film coat characteristics was investigated using X-ray microcomputed tomography (XμCT) and confocal laser scanning microscopy (CLSM). A quality by design approach utilising design of experiments (DOE) was used to optimise the conditions necessary for production of droplets at a small (20 μm) and large (70 μm) droplet size. Droplet size distribution was measured using real-time laser diffraction and the volume median diameter taken as a response. DOE yielded information on the relationship three critical process parameters: pump rate, atomisation pressure and coating-polymer concentration, had upon droplet size. The model generated was robust, scoring highly for model fit (R2 = 0.977), predictability (Q2 = 0.837), validity and reproducibility. Modelling confirmed that all parameters had either a linear or quadratic effect on droplet size and revealed an interaction between pump rate and atomisation pressure. Fluidised bed coating of tablet cores was performed with either small or large droplets followed by CLSM and XμCT imaging. Addition of commonly used contrast materials to the coating solution improved visualisation of the coating by XμCT, showing the coat as a discrete section of the overall tablet. Imaging provided qualitative and quantitative evidence revealing that smaller droplets formed thinner, more uniform and less porous film coats. PMID:27548263

Development and application of clean coal technology for power in Harbin Boiler Co. Ltd (HBC)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, W.; Yang, Z.

1999-07-01

The development and application of deNox burners and large CFB, as well as desulfurization techniques at the Harbin Boiler Co. ltd (HBC) are introduced in this paper. The plan to develop the power generation technology with high efficiency and low pollution for future market is also given in the paper.

High-level fluorescence labeling of gram-positive pathogens.

PubMed

Aymanns, Simone; Mauerer, Stefanie; van Zandbergen, Ger; Wolz, Christiane; Spellerberg, Barbara

2011-01-01

Fluorescence labeling of bacterial pathogens has a broad range of interesting applications including the observation of living bacteria within host cells. We constructed a novel vector based on the E. coli streptococcal shuttle plasmid pAT28 that can propagate in numerous bacterial species from different genera. The plasmid harbors a promoterless copy of the green fluorescent variant gene egfp under the control of the CAMP-factor gene (cfb) promoter of Streptococcus agalactiae and was designated pBSU101. Upon transfer of the plasmid into streptococci, the bacteria show a distinct and easily detectable fluorescence using a standard fluorescence microscope and quantification by FACS-analysis demonstrated values that were 10-50 times increased over the respective controls. To assess the suitability of the construct for high efficiency fluorescence labeling in different gram-positive pathogens, numerous species were transformed. We successfully labeled Streptococcus pyogenes, Streptococcus agalactiae, Streptococcus dysgalactiae subsp. equisimilis, Enterococcus faecalis, Enterococcus faecium, Streptococcus mutans, Streptococcus anginosus and Staphylococcus aureus strains utilizing the EGFP reporter plasmid pBSU101. In all of these species the presence of the cfb promoter construct resulted in high-level EGFP expression that could be further increased by growing the streptococcal and enterococcal cultures under high oxygen conditions through continuous aeration.

Resistance of Marine Bacterioneuston to Solar Radiation

PubMed Central

Agogué, Hélène; Joux, Fabien; Obernosterer, Ingrid; Lebaron, Philippe

2005-01-01

A total of 90 bacterial strains were isolated from the sea surface microlayer (i.e., bacterioneuston) and underlying waters (i.e., bacterioplankton) from two sites of the northwestern Mediterranean Sea. The strains were identified by sequence analysis, and growth recovery was investigated after exposure to simulated solar radiation. Bacterioneuston and bacterioplankton isolates were subjected to six different exposure times, ranging from 0.5 to 7 h of simulated noontime solar radiation. Following exposure, the growth of each isolate was monitored, and different classes of resistance were determined according to the growth pattern. Large interspecific differences among the 90 marine isolates were observed. Medium and highly resistant strains accounted for 41% and 22% of the isolates, respectively, and only 16% were sensitive strains. Resistance to solar radiation was equally distributed within the bacterioneuston and bacterioplankton. Relative contributions to the highly resistant class were 43% for γ-proteobacteria and 14% and 8% for α-proteobacteria and the Cytophaga/Flavobacterium/Bacteroides (CFB) group, respectively. Within the γ-proteobacteria, the Pseudoalteromonas and Alteromonas genera appeared to be highly resistant to solar radiation. The majority of the CFB group (76%) had medium resistance. Our study further provides evidence that pigmented bacteria are not more resistant to solar radiation than nonpigmented bacteria. PMID:16151115

Realization of BP neural network modeling based on NOXof CFB boiler in DCS

NASA Astrophysics Data System (ADS)

Bai, Jianyun; Zhu, Zhujun; Wang, Qi; Ying, Jiang

2018-02-01

In the CFB boiler installed with SNCR denitrification system, the mass concentration of NO X is difficult to be predicted by the conventional mathematical model, and the step response mathematical model, obtained by using the step disturbance test of ammonia injection,is inaccurate. this paper presents two kinds of BP neural network model, according to the relationship between the generated mass concentration of NO X and the load, the ratio of air to coal without using the SNCR system, as well as the relationship between the tested mass concentration of NO X and the load, the ratio of air to coal and the amount of ammonia using the SNCR system. then itrealized the on-line prediction of the mass concentration of NO X and the remaining mass concentration of NO X after reductionreaction in DCS system. the practical results show that the average error per hour between generation and the prediction of the amount of NO X mass concentration is within 10 mg/Nm3,the reducing reaction of measured and predicted hourly average error is within 2 mg/Nm3, all in error range, which provides a more accurate model for solvingthe problem on NO X automatic control of SNCR system.

Assessing cognitive functioning in ALS: A focus on frontal lobe processes.

PubMed

Gillingham, S M; Yunusova, Y; Ganda, A; Rogaeva, E; Black, S E; Stuss, D T; Zinman, L

2017-05-01

It is generally acknowledged that at least 50% of individuals with amyotrophic lateral sclerosis (ALS) will exhibit cognitive deficits outside of the characteristic motor neuron involvement. However, a specific cognitive profile has been difficult to ascertain due to disease-related testing barriers and limitations in the sensitivity and specificity of available assessment methods. This study assessed the level of functioning of extramotor frontal cognitive processes in ALS, and the amount of change in the functioning in these processes over time as disease progresses. Empirical tests validated for a model of frontal lobe functioning were modified into an assessment battery appropriate for individuals with ALS in a clinical setting (the ALS-CFB, Computerised Frontal Battery). Twenty ALS participants and 36 age- and education-matched neurologically healthy controls were tested, and a sub-sample of each group (11 ALS and 20 controls) re-tested after approximately nine months. Compared to standard neuropsychological screening tests that did not show a difference between ALS participants and healthy controls, the ALS-CFB illustrated a profile of extramotor frontal dysfunction involving energisation (preparing the neural system to respond) and executive functions, a profile that may be indicative of the nature of neurodegeneration in ALS.

Interactive Environment Familiarization and Indicator Trainer: User Evaluation

DTIC Science & Technology

2015-01-01

data collected as part of this study was approved either by Defence Research and Development Canada’s Human Research Ethics Board or by the Director ...deployment experience in Afghanistan. Participants were not remunerated for their participation as no abnormal stress or discomfort was anticipated (DAOD...Wojtarowicz (DRDC Toronto) Run Director : Cpl Philip Mach (DRDC Toronto) Work breakdown element: 12rr03 ACRONYMS CF Canadian Forces CFB

AMMPHS Trial Report CFB Valcartier, 28 September to 9 October 2009 (Compte Rendu D’Essais pour le AMMPHS BFC Valcartier du 28 Septembre au 9 Octobre 2009)

DTIC Science & Technology

2010-03-01

14 FIGURE 18: TUNNEL AND ROPE CLIMB...15 Tunnel and Rope Climb: Participants were required to run through a tunnel and ascend a rope ladder at the end; Figure 18: Tunnel and Rope...de la massagerie tels que PDA, telephones intelligents, Blackberry , etc. Note

Bacterial Activity at −2 to −20°C in Arctic Wintertime Sea Ice

PubMed Central

Junge, Karen; Eicken, Hajo; Deming, Jody W.

2004-01-01

Arctic wintertime sea-ice cores, characterized by a temperature gradient of −2 to −20°C, were investigated to better understand constraints on bacterial abundance, activity, and diversity at subzero temperatures. With the fluorescent stains 4′,6′-diamidino-2-phenylindole 2HCl (DAPI) (for DNA) and 5-cyano-2,3-ditoyl tetrazolium chloride (CTC) (for O2-based respiration), the abundances of total, particle-associated (>3-μm), free-living, and actively respiring bacteria were determined for ice-core samples melted at their in situ temperatures (−2 to −20°C) and at the corresponding salinities of their brine inclusions (38 to 209 ppt). Fluorescence in situ hybridization was applied to determine the proportions of Bacteria, Cytophaga-Flavobacteria-Bacteroides (CFB), and Archaea. Microtome-prepared ice sections also were examined microscopically under in situ conditions to evaluate bacterial abundance (by DAPI staining) and particle associations within the brine-inclusion network of the ice. For both melted and intact ice sections, more than 50% of cells were found to be associated with particles or surfaces (sediment grains, detritus, and ice-crystal boundaries). CTC-active bacteria (0.5 to 4% of the total) and cells detectable by rRNA probes (18 to 86% of the total) were found in all ice samples, including the coldest (−20°C), where virtually all active cells were particle associated. The percentage of active bacteria associated with particles increased with decreasing temperature, as did the percentages of CFB (16 to 82% of Bacteria) and Archaea (0.0 to 3.4% of total cells). These results, combined with correlation analyses between bacterial variables and measures of particulate matter in the ice as well as the increase in CFB at lower temperatures, confirm the importance of particle or surface association to bacterial activity at subzero temperatures. Measuring activity down to −20°C adds to the concept that liquid inclusions in frozen environments provide an adequate habitat for active microbial populations on Earth and possibly elsewhere. PMID:14711687

Rates of surface lowering and landscape development in southern South Africa: a cosmogenic view

NASA Astrophysics Data System (ADS)

Richardson, Janet; Vanacker, Veerle; Lang, Andreas; Hodgson, David

2016-04-01

The landscape of southern South Africa is characterised by large-scale erosion surfaces, including extensive pediments and multiple strath terraces, which document discordant river evolution through resistant quarzitic lithologies of the Cape Fold Belt (CFB). The timing and rate of erosion is poorly constrained. New cosmogenic ages from surfaces in South Africa are presented using in situ produced 10Be. Strath terraces in deeply incised rivers at two sites within the CFB indicate slow rates of erosion (1.54 - 11.79 m/Ma), which are some of the lowest rates recorded globally. Four pediment surfaces and a depth profile of the thickest pediment were also dated, and the results indicate that there are low rates of surface lowering on the pediments (0.44 - 1.24 m/Ma). The pediments are long-lived features (minimum exposure ages of 0.47 - 1.09 Ma), and are now deeply dissected. Given the minimum exposure ages, calculated river incision rates (42- 203 m/Ma) suggest that after a long period of geomorphic stability during pediment formation there was a discrete phase of increased geomorphic activity. The calculated minimum exposure ages are considered dubious because: 1) known rates of surrounding river incision (published and ours); 2) the climate conditions and time necessary for ferricrete formation on the pediment surfaces and; 3) the deeply incised catchments in the CFB on which the pediments sit, which all point to the pediments being much older. The pediments are fossilised remnants of a much larger geomorphic surface that formed after the main phase of exhumation in southern Africa. They form a store of sediment that currently sit above the surrounding rivers that have some of the lowest erosion rates in the world. These results indicate that steep topography can prevail even in areas of low erosion and tectonic quiescence, and that whilst cosmogenic dating of landscapes is an exciting development in earth sciences, care is needed especially in ancient settings. We strongly suggest benchmarking chronometric information with geomorphic and stratigraphic information.

Effect of feeding complete feed block containing rumen protected protein, non-protein nitrogen and rumen protected fat on improving body condition and carcass traits of cull ewes.

PubMed

Bhatt, R S; Sahoo, A

2017-12-01

Nutrient utilization, body condition and carcass traits of cull ewes were studied in three dietary regimens based on complete feed block (CFB) feeding to control (C) with rumen protected protein (RPP), CU [RPP + urea (6 g/kg)] and CUF [RPP + urea + rumen protected fat (RPF; 40 g/kg)]. The RPP component (g/kg) in C had 1% formaldehyde-treated soy flakes 50, mustard cake 50 and sesame cake 30. The mustard and sesame cakes were replaced with urea on equivalent N basis in CU and CUF. The ewes were offered ad libitum CFB composed (g/kg) of concentrate 650, roughage 300 and molasses 50. The digestibility of OM and EE was higher (p < 0.05) in CUF than in CU and C, while that of NDF and ADF was lower (p < 0.05). The CP digestibility was higher in both CU and CUF. Utilization of N and Ca was higher (p < 0.05) in CUF compared with C and CU. Urinary purine derivatives analysis and microbial N synthesis were similar in all the groups. Blood glucose concentration improved at 90 day compared with 0 day. Ruminal attributes showed a higher (p < 0.05) pH, total N, TCA precipitable N, entodiniomorphs and total ciliate population in CU and CUF than in the control. The CUF had higher (p < 0.01) DM, digestible OM and ME intake, which resulted in higher (p < 0.05) weight gain and better feed efficiency. Ewes in all the groups showed an improvement in carcass traits at 90 day. The pre-slaughter weight was higher (p < 0.05) and dissected and KOH bone content was lower in CUF. Thus, feeding of CFB with urea as a cheaper N source and RPF to enrich with energy supported the improved performance as evidenced from higher nutrient input, 'utilization and efficiency with enhanced carcass traits' for better marketability and returns from cull ewes. Journal of Animal Physiology and Animal Nutrition © 2017 Blackwell Verlag GmbH.

Origin and Role of Recycled Crust in Flood Basalt Magmatism: Case Study of the Central East Greenland Rifted Margin

NASA Astrophysics Data System (ADS)

Brown, E.; Lesher, C. E.

2015-12-01

Continental flood basalts (CFB) are extreme manifestations of mantle melting derived from chemically/isotopically heterogeneous mantle. Much of this heterogeneity comes from lithospheric material recycled into the convecting mantle by a range of mechanisms (e.g. subduction, delamination). The abundance and petrogenetic origins of these lithologies thus provide important constraints on the geodynamical origins of CFB magmatism, and the timescales of lithospheric recycling in the mantle. Basalt geochemistry has long been used to constrain the compositions and mean ages of recycled lithologies in the mantle. Typically, this work assumes the isotopic compositions of the basalts are the same as their mantle source(s). However, because basalts are mixtures of melts derived from different sources (having different fusibilities) generated over ranges of P and T, their isotopic compositions only indirectly represent the isotopic compositions of their mantle sources[1]. Thus, relating basalts compositions to mantle source compositions requires information about the melting process itself. To investigate the nature of lithologic source heterogeneity while accounting for the effects of melting during CFB magmatism, we utilize the REEBOX PRO forward melting model[2], which simulates adiabatic decompression melting in lithologically heterogeneous mantle. We apply the model to constrain the origins and abundance of mantle heterogeneity associated with Paleogene flood basalts erupted during the rift-to-drift transition of Pangea breakup along the Central East Greenland rifted margin of the North Atlantic igneous province. We show that these basalts were derived by melting of a hot, lithologically heterogeneous source containing depleted, subduction-modified lithospheric mantle, and <10% recycled oceanic crust. The Paleozoic mean age we calculate for this recycled crust is consistent with an origin in the region's prior subduction history, and with estimates for the mean age of recycled crust in the modern Iceland plume[3]. These results suggest that this lithospheric material was not recycled into the lower mantle before becoming entrained in the Iceland plume. [1] Rudge et al. (2013). GCA, 114, p112-143; [2] Brown & Lesher (2014). Nat. Geo., 7, p820-824; [3] Thirlwall et al. (2004). GCA, 68, p361-386

On the potential for CO2 mineral storage in continental flood basalts – PHREEQC batch- and 1D diffusion–reaction simulations

PubMed Central

2012-01-01

Continental flood basalts (CFB) are considered as potential CO2 storage sites because of their high reactivity and abundant divalent metal ions that can potentially trap carbon for geological timescales. Moreover, laterally extensive CFB are found in many place in the world within reasonable distances from major CO2 point emission sources. Based on the mineral and glass composition of the Columbia River Basalt (CRB) we estimated the potential of CFB to store CO2 in secondary carbonates. We simulated the system using kinetic dependent dissolution of primary basalt-minerals (pyroxene, feldspar and glass) and the local equilibrium assumption for secondary phases (weathering products). The simulations were divided into closed-system batch simulations at a constant CO2 pressure of 100 bar with sensitivity studies of temperature and reactive surface area, an evaluation of the reactivity of H2O in scCO2, and finally 1D reactive diffusion simulations giving reactivity at CO2 pressures varying from 0 to 100 bar. Although the uncertainty in reactive surface area and corresponding reaction rates are large, we have estimated the potential for CO2 mineral storage and identified factors that control the maximum extent of carbonation. The simulations showed that formation of carbonates from basalt at 40 C may be limited to the formation of siderite and possibly FeMg carbonates. Calcium was largely consumed by zeolite and oxide instead of forming carbonates. At higher temperatures (60 – 100 C), magnesite is suggested to form together with siderite and ankerite. The maximum potential of CO2 stored as solid carbonates, if CO2 is supplied to the reactions unlimited, is shown to depend on the availability of pore space as the hydration and carbonation reactions increase the solid volume and clog the pore space. For systems such as in the scCO2 phase with limited amount of water, the total carbonation potential is limited by the amount of water present for hydration of basalt. PMID:22697910

Studying the effectiveness of penetration enhancers to deliver retinol through the stratum cornum by in vivo confocal Raman spectroscopy.

PubMed

Mélot, Mickaël; Pudney, Paul D A; Williamson, Ann-Marie; Caspers, Peter J; Van Der Pol, Andre; Puppels, Gerwin J

2009-08-19

The purpose of this study is to monitor in vivo the effect of chemical penetration enhancers on the delivery of trans-retinol into human skin. Chemical penetration enhancers reversibly alter barrier properties of the SC by disruption of the membrane structures or maximising drug solubility with the skin. So far, most of permeation or penetration experiments are performed in vitro. Raman spectroscopy is uniquely placed to be able to measure biological processes in vivo and this paper shows for the first time that the effect of penetration enhancer on the delivery of trans-retinol can successfully be measured in vivo using this technique. Here, the volar forearm of volunteers was treated with four formulations. One formulation is a highly effective model delivery system identified from ex vivo experiments: trans-retinol in Propylene Glycol (PG)/ethanol, with PG being a well-known and efficient penetration enhancer. The other three formulations are based on 0.3% trans-retinol in Caprylic/Capric Acid Triglyceride (MYRITOL 318), an oil commonly used in skin creams but in two of them a specific penetration enhancer is added. One contains a lipid extractor, Triton X 100, whereas another formulation contains a lipid fluidiser, Oleic Acid. Solutions were applied once and measurements were performed up to 6 h after treatment. Remarkable differences in the delivery of trans-retinol between formulation with or without penetration enhancer can clearly be seen. Moreover, the type of penetration enhancer is also shown to influence the delivery. While using the Oleic Acid, which is a lipid fluidiser, a better delivery of trans-retinol in the skin can be detected. For the first time, the effect of penetration enhancer on the delivery of trans-retinol has been monitored, non invasively in vivo, with time.

How do Student Clients of a University-based Food Bank Cope with Food Insecurity?

PubMed

Farahbakhsh, Jasmine; Ball, Geoff D C; Farmer, Anna P; Maximova, Katerina; Hanbazaza, Mahitab; Willows, Noreen D

2015-12-01

To describe the food security status, food insecurity coping strategies, characteristics, and experiences of student clients of the Campus Food Bank (CFB) at the University of Alberta in Edmonton, Alberta, Canada. A convenience sample of 58 students completed a survey from April 2013 to April 2014. Food security status was determined using the "Adult Food Security Survey Module". Ninety percent of CFB student clients who participated in this study were food insecure, which included both moderately and severely food insecure groups. The most prevalent coping strategies for food insecurity included applying for a loan or bursary (86.2%), seeking employment or working more hours (84.5%), and purchasing food using a credit card (77.6%). Participants were a diverse mix of students, including graduate students (50.0%), international students (46.6%), and caregivers of children (24.1%). The most common primary sources of income were government student loans (29.3%) and research assistantships (20.7%). Most participants (82.8%) liked the food they received from the food bank. Food insecurity is highly prevalent among student clients of this university-based food bank. Students used a variety of coping strategies to increase their disposable income, highlighting the need for additional strategies to alleviate food insecurity among vulnerable students.

Nutritional quality and price of university food bank hampers.

PubMed

Willows, Noreen D; Au, Vivian

2006-01-01

Food insecurity appears to be a growing problem for post-secondary students, but little study has been made of the 51 campus-based food banks that exist. In 2003-04, the University of Alberta Campus Food Bank (CFB) distributed hampers intended to supply four days of food to 630 unique clients, of whom 207 (32.8%) were children. The nutritional adequacy of food hampers and cost saving to students were evaluated in the current study. Hampers prepared for one adult, and for one adult with one child, were nutritionally evaluated and scored for number of servings according to Canada's Food Guide to Healthy Eating. Two types of hampers were evaluated: those containing only non-perishable items, and those containing non-perishable and perishable items. Hamper contents were priced to establish the cost saving to students. The study revealed that a student with one child would receive up to 58.02 Canadian dollars worth of food in a hamper that contained perishable items. All hampers met the recommended minimum servings for each food group, but were very low in fat and protein from animal sources. Because students can obtain hampers only twice each month, the CFB is not the solution to food insecurity on campus. Awareness of the issue of post-secondary student food insecurity needs to be raised.

High-Level Fluorescence Labeling of Gram-Positive Pathogens

PubMed Central

Aymanns, Simone; Mauerer, Stefanie; van Zandbergen, Ger; Wolz, Christiane; Spellerberg, Barbara

2011-01-01

Fluorescence labeling of bacterial pathogens has a broad range of interesting applications including the observation of living bacteria within host cells. We constructed a novel vector based on the E. coli streptococcal shuttle plasmid pAT28 that can propagate in numerous bacterial species from different genera. The plasmid harbors a promoterless copy of the green fluorescent variant gene egfp under the control of the CAMP-factor gene (cfb) promoter of Streptococcus agalactiae and was designated pBSU101. Upon transfer of the plasmid into streptococci, the bacteria show a distinct and easily detectable fluorescence using a standard fluorescence microscope and quantification by FACS-analysis demonstrated values that were 10–50 times increased over the respective controls. To assess the suitability of the construct for high efficiency fluorescence labeling in different gram-positive pathogens, numerous species were transformed. We successfully labeled Streptococcus pyogenes, Streptococcus agalactiae, Streptococcus dysgalactiae subsp. equisimilis, Enterococcus faecalis, Enterococcus faecium, Streptococcus mutans, Streptococcus anginosus and Staphylococcus aureus strains utilizing the EGFP reporter plasmid pBSU101. In all of these species the presence of the cfb promoter construct resulted in high-level EGFP expression that could be further increased by growing the streptococcal and enterococcal cultures under high oxygen conditions through continuous aeration. PMID:21731607

CO-FIRING COAL: FEEDLOT AND LITTER BIOMASS (CFB AND CLB) FUELS IN PULVERIZED FUEL AND FIXED BED BURNERS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kalyan Annamalai; John Sweeten; Saqib Mukhtar

2003-08-28

Intensive animal feeding operations create large amounts of animal waste that must be safely disposed of in order to avoid environmental degradation. Cattle feedlots and chicken houses are two examples. In feedlots, cattle are confined to small pens and fed a high calorie grain-diet diet in preparation for slaughter. In chicken houses, thousands of chickens are kept in close proximity. In both of these operations, millions of tons of manure are produced every year. The manure could be used as a fuel by mixing it with coal in a 90:10 blend and firing it in an existing coal suspension firedmore » combustion systems. This technique is known as co-firing, and the high temperatures produced by the coal will allow the biomass to be completely combusted. Reburn is a process where a small percentage of fuel called reburn fuel is injected above the NO{sub x} producing, conventional coal fired burners in order to reduce NO{sub x}. The manure could also be used as reburn fuel for reducing NO{sub x} in coal fired plants. An alternate approach of using animal waste is to adopt the gasification process using a fixed bed gasifier and then use the gases for firing in gas turbine combustors. In this report, the cattle manure is referred to as feedlot biomass (FB) and chicken manure as litter biomass (LB). The report generates data on FB and LB fuel characteristics. Co-firing, reburn, and gasification tests of coal, FB, LB, coal: FB blends, and coal: LB blends and modeling on cofiring, reburn systems and economics of use of FB and LB have also been conducted. The biomass fuels are higher in ash, lower in heat content, higher in moisture, and higher in nitrogen and sulfur (which can cause air pollution) compared to coal. Small-scale cofiring experiments revealed that the biomass blends can be successfully fired, and NO{sub x} emissions will be similar to or lower than pollutant emissions when firing coal. Further experiments showed that biomass is twice or more effective than coal when used in a reburning process. Computer simulations for coal: LB blends were performed by modifying an existing computer code to include the drying and phosphorus (P) oxidation models. The gasification studies revealed that there is bed agglomeration in the case of chicken litter biomass due to its higher alkaline oxide content in the ash. Finally, the results of the economic analysis show that considerable fuel cost savings can be achieved with the use of biomass. In the case of higher ash and moisture biomass, the fuel cost savings is reduced.« less

Usage of humic materials for formulation of stable microbial inoculants

NASA Astrophysics Data System (ADS)

Kydralieva, K. A.; Khudaibergenova, B. M.; Elchin, A. A.; Gorbunova, N. V.; Muratov, V. S.; Jorobekova, Sh. J.

2009-04-01

Some microbes have been domesticated for environment service, for example in a variety of novel applications, including efforts to reduce environmental problems. For instance, antagonistic organisms can be used as biological control agents to reduce the use of chemical pesticides, or efficient degraders can be applied as bioprophylactics to minimise the spread of chemical pollutants. Microorganisms can also be used for the biological clean-up of polluted soil or as plant growth-promoting bacteria that stimulate nutrient uptake. Many microbial applications require large-scale cultivation of the organisms. The biomass production must then be followed by formulation steps to ensure long-term stability and convenient use. However, there remains a need to further develop knowledge on how to optimise fermentation of "non-conventional microorganisms" for environmental applications involving the intact living cells. The goal of presented study is to develop fermentation and formulation techniques for termolabile rhizobacteria isolates - Pseudomonas spp. with major biotechnical potential. Development of efficient and cost-effective media and process parameters giving high cell yields are important priorities. This also involves establishing fermentation parameters yielding cells well adapted to subsequent formulation procedures. Collectively, these strategies will deliver a high proportion of viable cells with good long-term survival. Our main efforts were focused on development of more efficient drying techniques for microorganisms, particularly spray drying and fluidised bed-drying. The advantages of dry formulations are that storage and delivery costs are much lower than for liquid formulations and that long-term survival can be very high if initial packaging is carefully optimised. In order to improve and optimise formulations various kinds of humics-based excipients have been added that have beneficial effects on the viability of the organisms and the storage stability of the product. It is known that humic substances can increase of live organism resistance to stress loads, in particular to chemical stress, low and high temperature. Spray- and fluidized-bed drying and addition of humate-based drying protectants were evaluated for the development of dry formulations of biocontrol and plant growth promoting rhizobacteria. The drying protectants - humic acids and sodium humate gave the highest initial survival rates and the most stable formulations, without significant losses of viability after storage for 1 month at 30oC. As a result, the specific plant growth promoting effect is retained. Thus, humic materials have an unfulfilled potential for biotechnology industries based on such applications. Acknowledgement. This research was supported by the grant of ISTC KR-993.2.

A Document Visualization Tool Customized to Explore DRDC Reports (Un outil de visualisation de document concu precisement pour explorer les rapports de RDDC)

DTIC Science & Technology

2011-08-01

context of flight simulators . ................................................................................................................... 14...particular area? Suppose a commander at CFB Shearwater wanted to find out more about how he/she can best deal with issues of pilots’ motion sickness...in the flight simulator on base. As a first step, one would enter, “motion sickness” as a query in HanDles, and get the relevant documents returned

Evaluation of the Impacts of Live Fire Training at CFB Shilo

DTIC Science & Technology

2003-04-22

des activites d’entrainement faites au secteur d’entrainement de la BFC Shilo et est la suite de la phase I, effectuee en septembre 2000. Durant la...premiere phase, trois champs de bataille avaient ete echantillonnes pour evaluer la contamination par les explosifs, les metaux, les COVs et les...iv Sommaire Le contexte international de demilitarisation, de la fermeture de bases et de la severite croissante des lois environnementales a

The Axum-Adwa basalt-trachyte complex: a late magmatic activity at the periphery of the Afar plume

NASA Astrophysics Data System (ADS)

Natali, C.; Beccaluva, L.; Bianchini, G.; Siena, F.

2013-08-01

The Axum-Adwa igneous complex consists of a basalt-trachyte (syenite) suite emplaced at the northern periphery of the Ethiopian plateau, after the paroxysmal eruption of the Oligocene (ca 30 Ma) continental flood basalts (CFB), which is related to the Afar plume activity. 40Ar/39Ar and K-Ar ages, carried out for the first time on felsic and basaltic rocks, constrain the magmatic age of the greater part of the complex around Axum to 19-15 Ma, whereas trachytic lavas from volcanic centres NE of Adwa are dated ca 27 Ma. The felsic compositions straddle the critical SiO2-saturation boundary, ranging from normative quartz trachyte lavas east of Adwa to normative (and modal) nepheline syenite subvolcanic domes (the obelisks stones of ancient axumites) around Axum. Petrogenetic modelling based on rock chemical data and phase equilibria calculations by PELE (Boudreau 1999) shows that low-pressure fractional crystallization processes, starting from mildly alkaline- and alkaline basalts comparable to those present in the complex, could generate SiO2-saturated trachytes and SiO2-undersaturated syenites, respectively, which correspond to residual liquid fractions of 17 and 10 %. The observed differentiation processes are consistent with the development of rifting events and formation of shallow magma chambers plausibly located between displaced (tilted) crustal blocks that favoured trapping of basaltic parental magmas and their fractionation to felsic differentiates. In syenitic domes, late- to post-magmatic processes are sometimes evidenced by secondary mineral associations (e.g. Bete Giorgis dome) which overprint the magmatic parageneses, and mainly induce additional nepheline and sodic pyroxene neo-crystallization. These metasomatic reactions were promoted by the circulation of Na-Cl-rich deuteric fluids (600-400 °C), as indicated by mineral and bulk rock chemical budgets as well as by δ18O analyses on mineral separates. The occurrence of this magmatism post-dating the CFB event, characterized by comparatively lower volume of more alkaline products, conforms to the progressive vanishing of the Afar plume thermal effects and the parallel decrease of the partial melting degrees of the related mantle sources. This evolution is also concomitant with the variation of the tectono-magmatic regime from regional lithospheric extension (CFB eruption) to localized rifting processes that favoured magmatic differentiation.

Tectonomagmatic significance of the picrite-rhyolite volcanism in the Northern Ethiopian plateau area

NASA Astrophysics Data System (ADS)

Natali, Claudio; Beccaluva, Luigi; Bianchini, Gianluca; Siena, Franca

2010-05-01

The Oligocene Continental Flood Basalts (CFB) of the Northern Ethiopia and the conjugate Yemen province testifies a huge volcanic event related to the "Afar plume" occurred at ca. 30 Ma (in 1 Ma or less; Hofmann et al., 1997) prior to the continental rifting stage. The zonal arrangement of CFB lavas with Low-Ti tholeiites (LT) in the west, High-Ti tholeiites (HT1) to the east and very High-Ti transitional basalts and picrites (HT2, TiO2 4-6 wt%) closer to the Afar triple junction has been considered a record of magmas generated from the flanks to the centre of a plume head, currently corresponding to the Afar hotspot (Beccaluva et al., 2009). In the central-eastern part of the plateau (Lalibela area), neighbouring the Afar escarpment, abundant rhyolites characterize the upper part of the volcanic sequence and have been interpreted as the differentiated products of CFB magmas (Ayalew et al., 2006). The unusual association of picrite and rhyolite magmas erupted in an elongated area, parallel to the Afar escarpment, appears to be related to peculiar tectonomagmatic events developed in the apical zone of a stretched lithosphere impinged by a mantle plume. As previously suggested, the HT basaltic and picritic magmas could have been generated in the innermost part (core) of the plume head from the hottest, deepest and most metasomatised mantle domains, enriched by "plume components" (Beccaluva et al., 2009). The late stages of these magmatic events were accompanied by the onset of continental rifting, with faulting and block tilting, leading to favourable conditions for magma differentiation in shallow (crustal) chambers located N-S along the future Afar Escarpment. Quantitative petrological modelling shows that efficient fractional crystallization processes of HT transitional basaltic magmas could result in highly differentiated peralkaline rhyolitic products, generally localized at the top (lower density) of the magma reservoirs. From these latter, abundant rhyolitic magma were erupted (sometimes alternating to HT basalts and picrites) during the paroxystic extensional phases which ultimately led to continental break-up and the formation of the Red Sea-Gulf of Aden-East African rift system centred in the Afar "triple junction". References: Ayalew et al. (2006). Geol. Soc. London Sp. Pub. 259, 121-130. Beccaluva et al. (2009). J. Petrol. 50, 1377-1403. Hofmann et al. (1997). Nature 389, 838-841.

Influence of school competitive food and beverage policies on obesity, consumption, and availability: a systematic review.

PubMed

Chriqui, Jamie F; Pickel, Margaret; Story, Mary

2014-03-01

The US Department of Agriculture recently issued an interim final rule governing the sale of foods and beverages sold outside of the school meal programs ("competitive foods and beverages" [CF&Bs]). To examine the potential influence that the federal rule may have based on peer-reviewed published studies examining the relationship between state laws and/or school district policies and student body mass index (BMI) and weight outcomes, consumption, and availability of CF&Bs. Keyword searches of peer-reviewed literature published between January 2005 and March 2013 were conducted using multiple databases. Titles and abstracts for 1160 nonduplicate articles were reviewed, with a full review conducted on 64 of those articles to determine their relevancy. Qualitative studies, studies of self-reported policies, or studies examining broad policies without a specific CF&B element were excluded. Twenty-four studies were selected for inclusion. Studies focused on state laws (n = 14), district policies (n = 8), or both (n = 2), with the majority of studies (n = 18) examining foods and beverages (as opposed to food-only or beverage-only policies). Sixteen studies examined prepolicy/postpolicy changes, and 8 studies examined postpolicy changes. Study designs were cross-sectional (n = 20), longitudinal (n = 3), or a combination (n = 1). Outcomes examined included change in BMI, weight, probability of overweight or obesity (n = 4), consumption (n = 10), and availability (n = 13); 3 studies examined more than 1 outcome. The majority of studies primarily reported results in the expected direction (n = 15), with the remaining studies (n = 9) reporting primarily mixed or nonsignificant results. In most cases, CF&B policies are associated with changes in consumption and/or availability in the expected direction; however, caution should be exercised, given that nearly all were cross-sectional. The influence of such policies on overall student consumption and BMI and weight outcomes was mixed. The findings hold promise for the likely influence of federal CF&B regulations on changes in student in-school consumption and in-school competitive food availability. Further research is needed to truly understand the association between these policies and overall consumption and weight outcomes.

Energetic Materials and Metals Contamination at CFB/ASU Wainwirght, Alberta Phase 1

DTIC Science & Technology

2008-11-01

Edmonton, Alberta). Metals analyzed for this study were silver (Ag), aluminium (Al), arsenic (As), boron (B), barium (Ba), beryllium (Be), bismuth 4...selenium (Se), antimony (Sb), tin (Sn), strontium (Sr), tellurium (Te), titanium (Ti), thallium (Tl), uranium (U), vanadium (V), zinc (Zn), and...mg/kg mg/kg mg/kg Aluminium - 9070 1040 Antimony 40 2 1 Arsenic 12 7 13.6 Barium 2000 177 73.4 Beryllium 8 40 40 Bismuth - 20 20 Boron - 10

Propellant Residues Deposition from Firing of AT4 Rockets

DTIC Science & Technology

2009-12-01

and 254 nm (cell path 1 cm), and a Finnigan SpectraSYSTEM AS300 autosampler. Samples were introduced with a 100-μL sample loop . Separations were...analytical laboratory. The remaining particle samples were left in sealed jars and stored on site in a refrigerator, and the snow sample was stored in a...Ranney. 1998. Characterization of antitank firing ranges at CFB Valcartier. WATC Wainwright, and CFAD Dundurn. DREV-R-9809. Val- Bélair, QC: DRDC

Field Demonstration and Validation of a New Device for Measuring Water and Solute Fluxes at CFB Borden

DTIC Science & Technology

2006-11-01

All Quality Control Reference Materials are acquired only from authorized vendors or sources commonly used by U.S. EPA Regional Laboratories...Institue of Standards and Testing (NITS) Standard Reference Materials (SRM) or to the U.S. EPA Reference Standards. Working Standards The commercial...contaminants from clothing or equipment by blowing, shaking or any other means that may disperse material into the air is prohibited. 7.1.3. All disposable

Temporal changes in community composition of heterotrophic bacteria during in situ iron enrichment in the western subarctic Pacific (SEEDS-II)

NASA Astrophysics Data System (ADS)

Kataoka, Takafumi; Suzuki, Koji; Hayakawa, Maki; Kudo, Isao; Higashi, Seigo; Tsuda, Atsushi

2009-12-01

Little is known about the effects of iron enrichment in high-nitrate low-chlorophyll (HNLC) waters on the community composition of heterotrophic bacteria, which are crucial to nutrient recycling and microbial food webs. Using denaturing gradient gel electrophoresis (DGGE) of 16S rDNA fragments, we investigated the heterotrophic eubacterial community composition in surface waters during an in situ iron-enrichment experiment (SEEDS-II) in the western subarctic Pacific in the summer of 2004. DGGE fingerprints representing the community composition of eubacteria differed inside and outside the iron-enriched patch. Sequencing of DGGE bands revealed that at least five phylotypes of α-proteobacteria including Roseobacter, Cytophaga-Flavobacteria- Bacteroides (CFB), γ-proteobacteria, and Actinobacteria occurred in almost all samples from the iron-enriched patch. Diatoms did not bloom during SEEDS-II, but the eubacterial composition in the iron-enriched patch was similar to that in diatom blooms observed previously. Although dissolved organic carbon (DOC) accumulation was not detected in surface waters during SEEDS-II, growth of the Roseobacter clade might have been particularly stimulated after iron additions. Two identified phylotypes of CFB were closely related to the genus Saprospira, whose algicidal activity might degrade the phytoplankton assemblages increased by iron enrichment. These results suggest that the responses of heterotrophic bacteria to iron enrichment could differ among phylotypes during SEEDS-II.

A Comparison of Characteristics and Food Insecurity Coping Strategies between International and Domestic Postsecondary Students Using a Food Bank Located on a University Campus.

PubMed

Hanbazaza, Mahitab; Ball, Geoff D C; Farmer, Anna P; Maximova, Katerina; Farahbakhsh, Jasmine; Willows, Noreen D

2017-12-01

We compared food insecurity status, coping strategies, demographic characteristics, and self-rated health of international and domestic postsecondary students requesting emergency food hampers from a campus food bank (CFB). We collected data from a cross-sectional convenience sample of domestic and international students who accessed the CFB at the University of Alberta. Food insecurity was prevalent (international students: n = 26/27 (96.2%), domestic students: n = 31/31 (100%)). Compared with their domestic peers, international students were less likely to rate their mental health negatively (14.8% vs 38.7%, P = 0.04). The primary income source was government loans (54.8%) for domestic students and research assistantships (33.3%) for international students. To cope with not having enough money for food, the majority of both student groups delayed bill payments or buying university supplies, applied for loans or bursaries, purchased food on credit, or worked more. International students were less likely to ask friends or relatives for food (48.1% vs 77.4%, P = 0.02). Domestic and international students mostly used similar coping strategies to address food insecurity; however, they paid for their education using different income sources. Distinct strategies for international and domestic students are required to allow more students to cover their educational and living expenses.

Application of antifungal CFB to increase the durability of cement mortar.

PubMed

Park, Jong-Myong; Park, Sung-Jin; Kim, Wha-Jung; Ghim, Sa-Youl

2012-07-01

Antifungal cement mortar or microbiological calcium carbonate precipitation on cement surface has been investigated as functional concrete research. However, these research concepts have never been fused with each other. In this study, we introduced the antifungal calciteforming bacteria (CFB) Bacillus aryabhattai KNUC205, isolated from an urban tunnel (Daegu, South Korea). The major fungal deteriogens in urban tunnel, Cladosporium sphaerospermum KNUC253, was used as a sensitive fungal strain. B. aryabhattai KNUC205 showed CaCO3 precipitation on B4 medium. Cracked cement mortar pastes were made and neutralized by modified methods. Subsequently, the mixture of B. aryabhattai KNUC205, conidiospore of C. sphaerospermum KNUC253, and B4 agar was applied to cement cracks and incubated at 18 degrees C for 16 days. B. aryabhattai KNUC205 showed fungal growth inhibition against C. sphaerospermum. Furthermore, B. aryabhattai KNUC205 showed crack remediation ability and water permeability reduction of cement mortar pastes. Taken together, these results suggest that the CaCO3 precipitation and antifungal properties of B. aryabhattai KNUC205 could be used as an effective sealing or coating material that can also prevent deteriorative fungal growth. This study is the first application and evaluation research that incorporates calcite formation with antifungal capabilities of microorganisms for an environment-friendly and more effective protection of cement materials. In this research, the conception of microbial construction materials was expanded.

Prospects for the development of coal-steam plants in Russia

NASA Astrophysics Data System (ADS)

Tumanovskii, A. G.

2017-06-01

Evaluation of the technical state of the modern coal-fired power plants and quality of coal consumed by Russian thermal power plants (TPP) is provided. Measures aimed at improving the economic and environmental performance of operating 150-800 MW coal power units are considered. Ways of efficient use of technical methods of NO x control and electrostatic precipitators' upgrade for improving the efficiency of ash trapping are summarized. Examples of turbine and boiler equipment efficiency upgrading through its deep modernization are presented. The necessity of the development and introduction of new technologies in the coal-fired power industry is shown. Basic technical requirements for a 660-800 MW power unit with the steam conditions of 28 MPa, 600/600°C are listed. Design solutions taking into account features of Russian coal combustion are considered. A field of application of circulating fluidized bed (CFB) boilers and their effectiveness are indicated. The results of development of a new generation coal-fired TPP, including a steam turbine with an increased efficiency of the compartments and disengaging clutch, an elevated steam conditions boiler, and a highly efficient NO x /SO2 and ash particles emission control system are provided. In this case, the resulting ash and slag are not to be sent to the ash dumps and are to be used to a maximum advantage. Technical solutions to improve the efficiency of coal gasification combined cycle plants (CCP) are considered. A trial plant based on a 16 MW gas turbine plant (GTP) and an air-blown gasifier is designed as a prototype of a high-power CCP. The necessity of a state-supported technical reequipment and development program of operating coal-fired power units, as well as putting into production of new generation coal-fired power plants, is noted.

Asphalt Roofing Shingles Into Energy Project Summary Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jameson, Rex, PE

2008-04-28

Based on a widely cited September, 1999 report by the Vermont Agency of Natural Resources, nearly 11 million tons of asphalt roofing shingle wastes are produced in the United States each year. Recent data suggests that the total is made up of about 9.4 million tons from roofing tear-offs and about 1.6 million tons from manufacturing scrap. Developing beneficial uses for these materials would conserve natural resources, promote protection of the environment and strengthen the economy. This project explored the feasibility of using chipped asphalt shingle materials in cement manufacturing kilns and circulating fluidized bed (CFB) boilers. A method ofmore » enhancing the value of chipped shingle materials for use as fuel by removing certain fractions for use as substitute raw materials for the manufacture of new shingles was also explored. Procedures were developed to prevent asbestos containing materials from being processed at the chipping facilities, and the frequency of the occurrence of asbestos in residential roofing tear-off materials was evaluated. The economic feasibility of each potential use was evaluated based on experience gained during the project and on a review of the well established use of shingle materials in hot mix asphalt. This project demonstrated that chipped asphalt shingle materials can be suitable for use as fuel in circulating fluidized boilers and cement kilns. More experience would be necessary to determine the full benefits that could be derived and to discover long term effects, but no technical barriers to full scale commercial use of chipped asphalt shingle materials in these applications were discovered. While the technical feasibility of various options was demonstrated, only the use of asphalt shingle materials in hot mix asphalt applications is currently viable economically.« less

Ionospheric Irregularities: Source, Structure, Plasma Processes and Effects on Sensor Systems

DTIC Science & Technology

1989-10-31

modified by using y - ye + w sin 0 sin 0 (20h) some of M orf et al.’s ideas. Fougere [1981] added a set of subroutines which find for each channel, the...correlation analysis has employed the modified Fedor algo- rithm (Fedor. 1967. CFB, this issue]. 3. ALGORITHM FOR THE SPECTRAL ANALYSIS The elements of the...knowledge, this paper presents with the every 240 m along the orbital track [Ifeelis et al., 1981]. Thus above data set the most detailed analysis of

Meeting today's challenges to supply tomorrow's energy. Clean fossil energy technical and policy seminar

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

2005-07-01

Papers discussed the coal policy of China, Russia, Indonesia and Vietnam; clean coal technology (small-scale coal power plants, carbon capture and sequestration, new coking process SCOPE21, coal gasification (HyPr-RING), CO{sub 2} reduction technology, Supercritical coal-fired units and CFB boilers, EAGLE project, coal liquefaction), the coal consumer's view of clean fossil energy policy, and natural gas policy and technology. Some of the papers only consist of the presentation overheads/viewgraphs.

Evaluation of the propellant residues emitted during 105-mm Leopard tank live firing at CFB Valcartier, Canada

DTIC Science & Technology

2009-12-01

good position to propose mitigation solutions and try to address the issues encountered with specific weapon systems. Projects to design new training...d’assaut comparativement aux munitions d’artillerie. La quantité de propergol dans la munition de 105 mm char d’assaut étant deux fois plus...theses rounds contain a tracer composition to help aim at the target. These rounds have a T at the 4 DRDC Valcartier TR 2009-420 end of their designation

Environmental Conditions of Surface Soils and Biomass Prevailing in the Training Area at CFB Gagetown, New Brunswick

DTIC Science & Technology

2003-09-26

sur Ia caracterisation environnementale de leurs secteurs d’entrainement majeurs afin d’ameliorer les connaissances des impacts de tous les types...et geographique. En 2001, Ia premiere phase de cette etude a consiste en la caracterisation hydrogeologique partielle dans la portion nord du...secteur d’entrainement. Cette premiere phase a implique le forage de 42 puits, afin de caracteriser la dynamique et la qualite des eaux souterraines. En

Mechanics of biological networks: from the cell cytoskeleton to connective tissue.

PubMed

Pritchard, Robyn H; Huang, Yan Yan Shery; Terentjev, Eugene M

2014-03-28

From the cell cytoskeleton to connective tissues, fibrous networks are ubiquitous in metazoan life as the key promoters of mechanical strength, support and integrity. In recent decades, the application of physics to biological systems has made substantial strides in elucidating the striking mechanical phenomena observed in such networks, explaining strain stiffening, power law rheology and cytoskeletal fluidisation - all key to the biological function of individual cells and tissues. In this review we focus on the current progress in the field, with a primer into the basic physics of individual filaments and the networks they form. This is followed by a discussion of biological networks in the context of a broad spread of recent in vitro and in vivo experiments.

Flowability of granular materials with industrial applications - An experimental approach

NASA Astrophysics Data System (ADS)

Torres-Serra, Joel; Romero, Enrique; Rodríguez-Ferran, Antonio; Caba, Joan; Arderiu, Xavier; Padullés, Josep-Manel; González, Juanjo

2017-06-01

Designing bulk material handling equipment requires a thorough understanding of the mechanical behaviour of powders and grains. Experimental characterization of granular materials is introduced focusing on flowability. A new prototype is presented which performs granular column collapse tests. The device consists of a channel whose design accounts for test inspection using visualization techniques and load measurements. A reservoir is attached where packing state of the granular material can be adjusted before run-off to simulate actual handling conditions by fluidisation and deaeration of the pile. Bulk materials on the market, with a wide range of particle sizes, can be tested with the prototype and the results used for classification in terms of flowability to improve industrial equipment selection processes.

Characterization of the bacterial communities associated with the bald sea urchin disease of the echinoid Paracentrotus lividus.

PubMed

Becker, Pierre T; Egea, Emilie; Eeckhaut, Igor

2008-06-01

The microbial communities involved in the bald sea urchin disease of the echinoid Paracentrotus lividus are investigated using culture-independent techniques. Lesions of diseased specimens from two locations in France, La Ciotat (Mediterranean Sea) and Morgat (Atlantic Ocean), are examined by Scanning Electron Microscopy (SEM) and the diversity of their microbiota is analysed by Denaturing Gradient Gel Electrophoresis (DGGE) and 16S rRNA gene clones libraries construction. Microscopic observations demonstrated that only the central area of the lesions is invaded by bacteria but not the peripheral zone and the surrounding healthy tissues. Molecular analysis identified at least 24 bacterial genomospecies in bald sea urchin lesions: 5 are Alphaproteobacteria, 10 are Gammaproteobacteria, 8 are CFB bacteria and 1 is a Fusobacteria. Out of them, 4 are observed in both locations while 10 occur only in the Atlantic Ocean and 10 only in the Mediterranean Sea. Gammaproteobacteria are the most represented in clones libraries from both locations, with respectively 65% and 43% of the total clones. CFB and Alphaproteobacteria accounted for the majority of the remaining clones and were detected by DGGE in virtually all samples from both stations. Our results demonstrate that bacterial communities observed on diseased individuals of the same echinoid species but originating from distinct locations are not similar and thus support the hypothesis that bacteria involved in the worldwide echinoid disease commonly called the bald sea urchin disease are opportunistic and not specific.

Development of post-harvest protocol of okra for export marketing.

PubMed

Dhall, R K; Sharma, S R; Mahajan, B V C

2014-08-01

The study was carried out on the harvesting and handling methods of okra with the objective to maintain the best quality of pods from harvesting to end consumer especially for export marketing. For that purpose okra cv. 'Punjab-8' pods were harvested with minimum handling (least injuries to the pubescence on the ridges of pod) and normal handling (no safety taken to prevent injuries on pods). Pods were precooled at 15 ± 1ºC, 90-95% RH; jumble packed in the CFB boxes of 2.0 Kg capacity and than stored at 8 ± 1ºC, 90-95% RH. The quality parameters of okra namely texture, chlorophyll content, physiological loss in weight, rotting percentage and general appearance were studied. The pods harvested with minimum handling and field packaging can retain their green colour, crisp texture (maximum force to puncture pod = 500.2 g) with minimum rotting (3.0%) and physiological loss in weight (15.8%) and good appearance upto 13 days of cold storage whereas normal handled pods can be stored upto 5 days at 8 ± 1ºC, 90-95% RH and thereafter lost their general appearance on the 7th day of storage and were discarded. Therefore, in order to maintain high quality of okra from harvesting to the final destination (consumer), the okra pods should be harvested with minimum handling followed by field packaging in CFB boxes.

Determination of cohesive and normal stresses and simulation of fluidization using kinetic theory

NASA Astrophysics Data System (ADS)

Bezbaruah, R.

1991-08-01

The general objective of this study is focused on the solid stresses involved in gas-solid flow. These stresses are generally included in the momentum conservation equations, essentially for stability and to prevent particles from collapsing to unreasonably low values of gas volume fraction. The first half of this work undertakes the measurement of the stresses in various powders by direct means, while the second part uses a newly developed kinetic theory constitutive equation for stress to predict the flow and also the solid's viscosity in a CFB. The cohesive or tensile stress found to exist in some classes of powders is measured using a Cohetester, based on which a cohesive force model is derived, which is sensitive to the characteristic properties of the powder material. The normal stress is measured using a Consolidometer, and the powder solid's modulus is obtained as a function of the volume fraction. The solid's modulus is seen to vary with particle size and particle type, with the smaller size particles being more compressible. The simulation of flow in the CFB using Gidaspow's (1991) extension of Ding's (1990) kinetic theory model to dilute phase flow, predicts realistic values of solids' viscosity that are comparable to viscosities obtained experimentally by Miller (1991). However, to obtain a match between the two, the value of the restitution coefficient has to be close to unity. The flow behavior showed periodic oscillations of flow (turbulence) as seen in a real system.

From initiation to termination: a petrostratigraphic tour of the Ethiopian Low-Ti Flood Basalt Province

NASA Astrophysics Data System (ADS)

Krans, S. R.; Rooney, T. O.; Kappelman, J.; Yirgu, G.; Ayalew, D.

2018-05-01

Continental flood basalts (CFBs), thought to preserve the magmatic record of an impinging mantle plume head, offer spatial and temporal insights into melt generation processes in large igneous provinces (LIPs). Despite the utility of CFBs in probing mantle plume composition, these basalts typically erupt fractionated compositions, suggestive of significant residence time in the continental lithosphere. The location and duration of residence within the lithosphere provide additional insights into the flux of plume-related magmas. The NW Ethiopian plateau offers a well-preserved stratigraphic sequence from flood basalt initiation to termination, and is thus an important target for study of CFBs. This study examines modal observations within a stratigraphic framework and places these observations within the context of the magmatic evolution of the Ethiopian CFB province. Data demonstrate multiple pulses of magma recharge punctuated by brief shut-down events, with initial flows fed by magmas that experienced deeper fractionation (lower crust). Broad changes in modal mineralogy and flow cyclicity are consistent with fluctuating changes in magmatic flux through a complex plumbing system, indicating pulsed magma flux and an overall shallowing of the magmatic plumbing system over time. The composition of plagioclase megacrysts suggests a constant replenishing of new primitive magma recharging the shallow plumbing system during the main phase of volcanism, reaching an apex prior to flood basalt termination. The petrostratigraphic data sets presented in this paper provide new insight into the evolution of a magma plumbing system in a CFB province.

Effects of tissue mechanical and acoustic anisotropies on the performance of a cross-correlation-based ultrasound strain imaging method.

PubMed

Li, He; Lee, Wei-Ning

2017-02-21

The anisotropic mechanical properties (mechanical anisotropy) and view-dependent ultrasonic backscattering (acoustic anisotropy) of striated muscle due to the underlying myofiber arrangement have been well documented, but whether they impact on ultrasound strain imaging (USI) techniques remains unclear. The aim of this study was therefore to investigate the performance of a cross-correlation-based two-dimensional (2D) USI method in anisotropic media under controlled quasi-static compression in silico and in vitro. First, synthetic pre- and post-deformed 2D radiofrequency images of anisotropic phantoms were simulated in two scenarios to examine the individual effect of the mechanical and acoustic anisotropies on strain estimation. In the first scenario, the phantom was defined to be transversely isotropic with the scatterer amplitudes following a zero-mean Gaussian distribution, while in the second scenario, the phantom was defined to be mechanically isotropic with Gaussian distributed scatterer amplitudes correlated along the principal directions of pre-defined fibers. These two anisotropies were then jointly incorporated into the ultrasound image simulation model with additional depth-dependent attenuation. Three imaging planes-the fiber plane with the fiber direction perpendicular to the ultrasound beam (TIS perp_fb ), the fiber plane with the fiber direction parallel to the beam (TIS para ), and the transverse fiber plane (TIS perp_cfb )-were studied. The absolute relative error (ARE) of the lateral strain estimates in TIS perp_fb (20.99  ±  15.65%) was much higher than that in TIS perp_cfb (4.14  ±  3.17%). The ARE in TIS para was unavailable owing to the large spatial extent of false peaks. The effect of tissue anisotropy on the performance of the 2D USI was further confirmed in an in vitro porcine skeletal muscle phantom. The best in-plane strain quality was again shown in TIS perp_cfb (elastographic signal-to-noise ratio, or SNR e :  >25 dB), whereas the most unreliable strain estimates were found as expected in TIS para (SNR e :  <10 dB). The strain filter explained the effect of the mechanical anisotropy and required the underlying strain to be within an optimal range for estimation. Sonographic SNR (SNR s ) was found to be altered by the acoustic anisotropy and was much lower in TIS para (~10 dB) than in TIS perp_fb (~50 dB) in vitro, which affected the accuracy of the strain estimation. Speckle size showed no evident impact on strain estimation but requires further examination.

Effects of tissue mechanical and acoustic anisotropies on the performance of a cross-correlation-based ultrasound strain imaging method

NASA Astrophysics Data System (ADS)

Li, He; Lee, Wei-Ning

2017-02-01

The anisotropic mechanical properties (mechanical anisotropy) and view-dependent ultrasonic backscattering (acoustic anisotropy) of striated muscle due to the underlying myofiber arrangement have been well documented, but whether they impact on ultrasound strain imaging (USI) techniques remains unclear. The aim of this study was therefore to investigate the performance of a cross-correlation-based two-dimensional (2D) USI method in anisotropic media under controlled quasi-static compression in silico and in vitro. First, synthetic pre- and post-deformed 2D radiofrequency images of anisotropic phantoms were simulated in two scenarios to examine the individual effect of the mechanical and acoustic anisotropies on strain estimation. In the first scenario, the phantom was defined to be transversely isotropic with the scatterer amplitudes following a zero-mean Gaussian distribution, while in the second scenario, the phantom was defined to be mechanically isotropic with Gaussian distributed scatterer amplitudes correlated along the principal directions of pre-defined fibers. These two anisotropies were then jointly incorporated into the ultrasound image simulation model with additional depth-dependent attenuation. Three imaging planes—the fiber plane with the fiber direction perpendicular to the ultrasound beam (TISperp_fb), the fiber plane with the fiber direction parallel to the beam (TISpara), and the transverse fiber plane (TISperp_cfb)—were studied. The absolute relative error (ARE) of the lateral strain estimates in TISperp_fb (20.99  ±  15.65%) was much higher than that in TISperp_cfb (4.14  ±  3.17%). The ARE in TISpara was unavailable owing to the large spatial extent of false peaks. The effect of tissue anisotropy on the performance of the 2D USI was further confirmed in an in vitro porcine skeletal muscle phantom. The best in-plane strain quality was again shown in TISperp_cfb (elastographic signal-to-noise ratio, or SNRe:  >25 dB), whereas the most unreliable strain estimates were found as expected in TISpara (SNRe:  <10 dB). The strain filter explained the effect of the mechanical anisotropy and required the underlying strain to be within an optimal range for estimation. Sonographic SNR (SNRs) was found to be altered by the acoustic anisotropy and was much lower in TISpara (~10 dB) than in TISperp_fb (~50 dB) in vitro, which affected the accuracy of the strain estimation. Speckle size showed no evident impact on strain estimation but requires further examination.

C6 GPMG and 40 mm AGL Weapon Integrated on RWS Mounted on TAPV Platform: Probability of Hit Methodology

DTIC Science & Technology

2010-09-01

nationale, 2010 DRDC Valcartier CR 2010-237 i Abstract …….. A probability of hit ( PHit ) methodology has been developed to characterize the...CFB (Canadian Forces Base). Résumé …..... Une méthodologie de probabilité d’impact ( PHit ) a été développée pour caractériser la performance globale...the crew commander and gunner from their respective crew stations inside the vehicle. A probability of hit ( PHit ) methodology has been developed to

Training vs. Education at the Army War College: The Benefits of a Return to the Past

DTIC Science & Technology

2014-05-22

strengthen the American economy, and later to recover from the Great Depression . Government officials and citizens also desired to avoid another war, and...of the Depression in 1929, the U.S. government concentrated on economic recovery, leading to an even greater increase in the fiscal restraints...Conference- Dr. Andrew Bacevich,” YouTube video, 8:35, http://www.youtube.com/watch?v =X6K6aagV9KU&list=PLBA15ADDE22B06CFB (accessed January 23, 2014

Aircraft Attitude Awareness Workshop Proceedings

DTIC Science & Technology

1987-04-01

MO Mr. Paul Summers, McDonnel Douglas Corp, St Louis, MO Dr. Stanley ROSCO, New Mexico State Univ. and ILLIANA Aviation Sciences Ltd, Las Cruces...CFB Cold Lake Alberta, Canada Dr. Stanley N. Roscoe New Mexico State Univ. b Las Cruces, NM Illiana Aviation Sciences Dr. Robert ti. Taylor...Enable w i n p a n t o m J f n t J l n own & LA whfle f l y l n s formnation o Reduce Cockpit Sorkload o Aid Recogni t ion o f L‘r.ex?ected

Final Environmental Impact Statement for the JEA Circulating Fluidized Bed Combustor Project

DOE Office of Scientific and Technical Information (OSTI.GOV)

N /A

2000-06-30

This EIS assesses environmental issues associated with constructing and demonstrating a project that would be cost-shared by DOE and JEA (formerly the Jacksonville Electric Authority) under the Clean Coal Technology Program. The project would demonstrate circulating fluidized bed (CFB) combustion technology at JEA's existing Northside Generating Station in Jacksonville, Florida, about 9 miles northeast of the downtown area of Jacksonville. The new CFB combustor would use coal and petroleum coke to generate nearly 300 MW of electricity by repowering the existing Unit 2 steam turbine, a 297.5-MW unit that has been out of service since 1983. The proposed project ismore » expected to demonstrate emission levels of sulfur dioxide (SO{sub 2}), oxides of nitrogen (NO{sub x}), and particulate matter that would be lower than Clean Air Act limits while at the same time producing power more efficiently and at less cost than conventional coal utilization technologies. At their own risk, JEA has begun initial construction activities without DOE funding. Construction would take approximately two years and, consistent with the original JEA schedule, would be completed in December 2001. Demonstration of the proposed project would be conducted during a 2-year period from March 2002 until March 2004. In addition, JEA plans to repower the currently operating Unit 1 steam turbine about 6 to 12 months after the Unit 2 repowering without cost-shared funding from DOE. Although the proposed project consists of only the Unit 2 repowering, this EIS analyzes the Unit 1 repowering as a related action. The EIS also considers three reasonably foreseeable scenarios that could result from the no-action alternative in which DOE would not provide cost-shared funding for the proposed project. The proposed action, in which DOE would provide cost-shared finding for the proposed project, is DOE's preferred alternative. The EIS evaluates the principal environmental issues, including air quality, traffic, noise, and ecological resources, that could result from construction and operation of the proposed project. Key findings include that maximum modeled increases in ground-level concentrations of SO{sub 2} nitrogen dioxide (NO{sub 2}), and particulate matter (for the proposed project alone or in conjunction with the related action) would always be less than 10% of their corresponding standards for increases in pollutants. For potential cumulative air quality impacts, results of modeling regional sources and the proposed project indicate that the maximum 24-hour average SO{sub 2} concentration would closely approach (i.e., 97%) but not exceed the corresponding Florida standard. After the Unit 1 repowering, results indicate that the maximum 24-hour average SO{sub 2} concentration would be 91% of the Florida standard. Concentrations for other averaging periods and pollutants would be lower percentages of their standards. Regarding toxic air pollutants from the proposed project, the maximum annual cancer risk to a member of the public would be approximately 1 in 1 million; given the conservative assumptions in the estimate, the risk would probably be less. With regard to threatened and endangered species, impacts to manatees, gopher tortoises, and other species would be negligible or non-existent. Construction-induced traffic would result in noticeable congestion. In the unlikely event that all coal were transported by rail, up to 3 additional trains per week would exacerbate impacts associated with noise, vibration, and blocked roads at on-grade rail crossings. Additional train traffic could be minimized by relying more heavily on barges and ships for coal transport, which is likely to be a more economic fuel delivery mode. During construction of the proposed project, noise levels would increase from the current operational levels. Except possibly during steam blowouts and possibly during operation of equipment used to construct a nearby segment of a conveyor, construction noise should not appreciably affect the background noise of nearby residences or exceed local noise limitations. The preferred alternative for management of the combustion ash would be to sell it as a by-product to offsite customers. If more than approximately 70% of the ash could be sold over the 30-year lifetime of Northside Generating Station, the 40-acre storage site would be sufficient for complete containment.« less

Beach groundwater dynamics

NASA Astrophysics Data System (ADS)

Horn, Diane P.

2002-11-01

An understanding of the interaction between surface and groundwater flows in the swash zone is necessary to understand beach profile evolution. Coastal researchers have recognized the importance of beach watertable and swash interaction to accretion and erosion above the still water level (SWL), but the exact nature of the relationship between swash flows, beach watertable flow and cross-shore sediment transport is not fully understood. This paper reviews research on beach groundwater dynamics and identifies research questions which will need to be answered before swash zone sediment transport can be successfully modelled. After defining the principal terms relating to beach groundwater, the behavior, measurement and modelling of beach groundwater dynamics is described. Research questions related to the mechanisms of surface-subsurface flow interaction are reviewed, particularly infiltration, exfiltration and fluidisation. The implications of these mechanisms for sediment transport are discussed.

Genetic control of the alternative pathway of complement in humans and age-related macular degeneration

PubMed Central

Hecker, Laura A.; Edwards, Albert O.; Ryu, Euijung; Tosakulwong, Nirubol; Baratz, Keith H.; Brown, William L.; Issa, Peter Charbel; Scholl, Hendrik P.; Pollok-Kopp, Beatrix; Schmid-Kubista, Katharina E.; Bailey, Kent R.; Oppermann, Martin

2010-01-01

Activation of the alternative pathway of complement is implicated in common neurodegenerative diseases including age-related macular degeneration (AMD). We explored the impact of common variation in genes encoding proteins of the alternative pathway on complement activation in human blood and in AMD. Genetic variation across the genes encoding complement factor H (CFH), factor B (CFB) and component 3 (C3) was determined. The influence of common haplotypes defining transcriptional and translational units on complement activation in blood was determined in a quantitative genomic association study. Individual haplotypes in CFH and CFB were associated with distinct and novel effects on plasma levels of precursors, regulators and activation products of the alternative pathway of complement in human blood. Further, genetic variation in CFH thought to influence cell surface regulation of complement did not alter plasma complement levels in human blood. Plasma markers of chronic activation (split-products Ba and C3d) and an activating enzyme (factor D) were elevated in AMD subjects. Most of the elevation in AMD was accounted for by the genetic variation controlling complement activation in human blood. Activation of the alternative pathway of complement in blood is under genetic control and increases with age. The genetic variation associated with increased activation of complement in human blood also increased the risk of AMD. Our data are consistent with a disease model in which genetic variation in the complement system increases the risk of AMD by a combination of systemic complement activation and abnormal regulation of complement activation in local tissues. PMID:19825847

Intelligent Control via Wireless Sensor Networks for Advanced Coal Combustion Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aman Behal; Sunil Kumar; Goodarz Ahmadi

2007-08-05

Numerical Modeling of Solid Gas Flow, System Identification for purposes of modeling and control, and Wireless Sensor and Actor Network design were pursued as part of this project. Time series input-output data was obtained from NETL's Morgantown CFB facility courtesy of Dr. Lawrence Shadle. It was run through a nonlinear kernel estimator and nonparametric models were obtained for the system. Linear and first-order nonlinear kernels were then utilized to obtain a state-space description of the system. Neural networks were trained that performed better at capturing the plant dynamics. It is possible to use these networks to find a plant modelmore » and the inversion of this model can be used to control the system. These models allow one to compare with physics based models whose parameters can then be determined by comparing them against the available data based model. On a parallel track, Dr. Kumar designed an energy-efficient and reliable transport protocol for wireless sensor and actor networks, where the sensors could be different types of wireless sensors used in CFB based coal combustion systems and actors are more powerful wireless nodes to set up a communication network while avoiding the data congestion. Dr. Ahmadi's group studied gas solid flow in a duct. It was seen that particle concentration clearly shows a preferential distribution. The particles strongly interact with the turbulence eddies and are concentrated in narrow bands that are evolving with time. It is believed that observed preferential concentration is due to the fact that these particles are flung out of eddies by centrifugal force.« less

Community structures of actively growing bacteria shift along a north-south transect in the western North Pacific

PubMed Central

Taniguchi, Akito; Hamasaki, Koji

2008-01-01

Bacterial community structures and their activities in the ocean are tightly coupled with organic matter fluxes and thus control ocean biogeochemical cycles. Bromodeoxyuridine (BrdU), halogenated nucleoside and thymidine analogue, has been recently used to monitor actively growing bacteria (AGB) in natural environments. We labelled DNA of proliferating cells in seawater bacterial assemblages with BrdU and determined community structures of the bacteria that were possible key species in mediating biochemical reactions in the ocean. Surface seawater samples were collected along a north-south transect in the North Pacific in October 2003 and subjected to BrdU magnetic beads immunocapture and PCR-DGGE (BUMP-DGGE) analysis. Change of BrdU-incorporated community structures reflected the change of water masses along a north-south transect from subarctic to subtropical gyres in the North Pacific. We identified 25 bands referred to AGB as BrdU-incorporated phylotypes, belonging to Alphaproteobacteria (5 bands), Betaproteobacteria (1 band), Gammaproteobacteria (4 bands), Cytophaga-Flavobacterium-Bacteroides (CFB) group bacteria (5 bands), Gram-positive bacteria (6 bands), and Cyanobacteria (4 bands). BrdU-incorporated phylotypes belonging to Vibrionales, Alteromonadales and Gram-positive bacteria appeared only at sampling stations in a subtropical gyre, while those belonging to Roseobacter-related bacteria and CFB group bacteria appeared at the stations in both subarctic and subtropical gyres. Our result revealed phylogenetic affiliation of AGB and their dynamic change along with north-south environmental gradients in open oceans. Different species of AGB utilize different amount and kinds of substrates, which can affect the change of organic matter fluxes along transect. PMID:18177366

Dynamical constraints on kimberlite volcanism

NASA Astrophysics Data System (ADS)

Sparks, R. S. J.; Baker, L.; Brown, R. J.; Field, M.; Schumacher, J.; Stripp, G.; Walters, A.

2006-07-01

Kimberlite volcanism involves the ascent of low viscosity (0.1 to 1 Pa s) and volatile-rich (CO 2 and H 2O) ultrabasic magmas from depths of 150 km or greater. Theoretical models and empirical evidence suggest ascent along narrow (˜1 m) dykes at speeds in the range > 4 to 20 m/s. With typical dyke breadths of 1 to 10 km, magma supply rates are estimated in the range 10 2 to 10 5 m 3/s with eruption durations of many hours to months. Based on observations, theory and experiments we propose a four-stage model for kimberlite eruptions to explain the main geological relationships of kimberlites. In stage I magma reaches the Earth's surface along fissures and erupts explosively due to their high volatile content. The early flow exit conditions are overpressured with choked flow conditions; an exit velocity of ˜200 m/s is estimated as representative. Explosive expansion and near surface overpressures initiate crater and pipe formation from the top downwards. In stage II under-pressures (the difference between the lithostatic pressure and pressure of the erupting mixture) develop within the evolving pipe causing rock bursting at depth, undermining overlying rocks and causing down-faulting and crater rim slumping. Rocks falling into the pipe interior are ejected by the strong explosive flows. Stage II is the erosive stage of pipe formation. As the pipe widens and deepens larger under-pressures develop enhancing pipe wall instability. A critical threshold is reached when the exit pressure falls to one atmosphere. As the pipe widens and deepens further the gas exit velocity declines and ejecta becomes trapped within the pipe, initiating stage III. A fluidised bed of pyroclasts develops within the pipe as the eruption wanes to form typical massive volcaniclastic kimberlite. Marginal breccias represent the transition between stages II and III. After the eruption stage IV is a period of hydrothermal metamorphism (principally serpentinisation) and alteration as the pipe cools and meteoric waters infiltrate the hot pipe fill. Following an eruption an open crater can be filled by kimberlite- and country-rock derived sediments, forming the crater-facies.

Fault textures in volcanic conduits: evidence for seismic trigger mechanisms during silicic eruptions

NASA Astrophysics Data System (ADS)

Tuffen, Hugh; Dingwell, Don

2005-04-01

It is proposed that fault textures in two dissected rhyolitic conduits in Iceland preserve evidence for shallow seismogenic faulting within rising magma during the emplacement of highly viscous lava flows. Detailed field and petrographic analysis of such textures may shed light on the origin of long-period and hybrid volcanic earthquakes at active volcanoes. There is evidence at each conduit investigated for multiple seismogenic cycles, each of which involved four distinct evolutionary phases. In phase 1, shear fracture of unrelaxed magma was triggered by shear stress accumulation during viscous flow, forming the angular fracture networks that initiated faulting cycles. Transient pressure gradients were generated as the fractures opened, which led to fluidisation and clastic deposition of fine-grained particles that were derived from the fracture walls by abrasion. Fracture networks then progressively coalesced and rotated during subsequent slip (phase 2), developing into cataclasite zones with evidence for multiple localised slip events, fluidisation and grain size reduction. Phase 2 textures closely resemble those formed on seismogenic tectonic faults characterised by friction-controlled stick-slip behaviour. Increasing cohesion of cataclasites then led to aseismic, distributed ductile deformation (phase 3) and generated deformed cataclasite zones, which are enriched in metallic oxide microlites and resemble glassy pseudotachylite. Continued annealing and deformation eventually erased all structures in the cataclasite and formed microlite-rich flow bands in obsidian (phase 4). Overall, the mixed brittle-ductile textures formed in the magma appear similar to those formed in lower crustal rocks close to the brittle-ductile transition, with the rheological response mediated by strain-rate variations and frictional heating. Fault processes in highly viscous magma are compared with those elsewhere in the crust, and this comparison is used to appraise existing models of volcano seismic activity. Based on the textures observed, it is suggested that patterns of long-period and hybrid earthquakes at silicic lava domes reflect friction-controlled stick-slip movement and eventual healing of fault zones in magma, which are an accelerated and smaller-scale analogue of tectonic faults.

Flow Sorting of Marine Bacterioplankton after Fluorescence In Situ Hybridization

PubMed Central

Sekar, Raju; Fuchs, Bernhard M.; Amann, Rudolf; Pernthaler, Jakob

2004-01-01

We describe an approach to sort cells from coastal North Sea bacterioplankton by flow cytometry after in situ hybridization with rRNA-targeted horseradish peroxidase-labeled oligonucleotide probes and catalyzed fluorescent reporter deposition (CARD-FISH). In a sample from spring 2003 >90% of the cells were detected by CARD-FISH with a bacterial probe (EUB338). Approximately 30% of the microbial assemblage was affiliated with the Cytophaga-Flavobacterium lineage of the Bacteroidetes (CFB group) (probe CF319a), and almost 10% was targeted by a probe for the β-proteobacteria (probe BET42a). A protocol was optimized to detach cells hybridized with EUB338, BET42a, and CF319a from membrane filters (recovery rate, 70%) and to sort the cells by flow cytometry. The purity of sorted cells was >95%. 16S rRNA gene clone libraries were constructed from hybridized and sorted cells (S-EUB, S-BET, and S-CF libraries) and from unhybridized and unsorted cells (UNHYB library). Sequences related to the CFB group were significantly more frequent in the S-CF library (66%) than in the UNHYB library (13%). No enrichment of β-proteobacterial sequence types was found in the S-BET library, but novel sequences related to Nitrosospira were found exclusively in this library. These bacteria, together with members of marine clade OM43, represented >90% of the β-proteobacteria in the water sample, as determined by CARD-FISH with specific probes. This illustrates that a combination of CARD-FISH and flow sorting might be a powerful approach to study the diversity and potentially the activity and the genomes of different bacterial populations in aquatic habitats. PMID:15466568

Department of National Defence's use of thermography for facilities maintenance

NASA Astrophysics Data System (ADS)

Kittson, John E.

1990-03-01

Since the late seventies DND through the Director General Works has been actively encouraging the use of thermography as an efficient and effective technique for supporting preventive maintenance quality assurance and energy conservation programs at Canadian Forces Bases (CFBs). This paper will provide an overview of DND''s experiences in the utilization of thermography for facilities maintenance applications. 1. HISTORICAL MILESTONES The following are milestones of DND''s use of thermography: a. Purchase of Infrared Equipment In 1976/77 DND purchased five AGA 750 Infrared Thermovision Systems which were distributed to commands. In 1980/81/82 six AGA liOs five AGA TPT8Os two AGA 782s and one AGA 720 were acquired. Finally DND also purchased seven AGEMA 870 systems during 1987/88. b. First and Second Interdepartaental Building Thermography Courses In 1978 and 1980 DND hosted two building thermography courses that were conducted by Public Works Canada. c. CE Thermographer Specialist Training Courses DND developed a training standard in 1983 for Construction Engineering (CE) Thermographer qualification which included all CE applications of thermography. The first annual inhouse training course was conducted at CFB Borden Ontario in 1984. These are now being conducted at the CFB Chilliwack Detachment in Vernon British Columbia. 2 . MARKETING FACILITIES MAINTENANCE IR Of paramount importance for successfully developing DND appreciation for thermography was providing familiarization training to CE staff at commands and bases. These threeday presentations emphasized motivational factors conducting thermographic surveys and utilizing infrared data of roofs electrical/mechanical systems heating plants steam distribution and building enclosures. These factors consisted mainly of the following objectives: a. preventive maintenance by locating deficiencies to be repaired b. quality assurance by verification of workmanship materials and design c. energy conservation by locating heat loss areas 2 / SPIE Vol. 1313 Thermosense XII (1990)

Relationship Between FEV1 and Patient-Reported Outcomes Changes: Results of a Meta-Analysis of Randomized Trials in Stable COPD.

PubMed

de la Loge, Christine; Tugaut, Béatrice; Fofana, Fatoumata; Lambert, Jérémy; Hennig, Michael; Tschiesner, Uta; Vahdati-Bolouri, Mitra; Segun Ismaila, Afisi; Suresh Punekar, Yogesh

2016-03-15

Background: This meta-analysis assessed the relationship between change from baseline (CFB) in spirometric measurements (trough forced expiratory volume in 1 second [FEV 1 ] and FEV 1 area under the curve [AUC]) and patient-reported outcomes (St. George's Respiratory Questionnaire total score [SGRQ] CFB, Transition Dyspnea Index [TDI] and exacerbation rates) after 6-12 months' follow-up, using study treatment-group level data. Methods: A systematic literature search was performed for randomized controlled trials of ≥24 weeks duration in adults with chronic obstructive pulmonary disease (COPD). Studies reporting ≥1 spirometric measurement and ≥1 patient-reported outcome (PRO) at baseline and at study endpoint were selected. The relationships between PROs and spirometric endpoints were assessed using Pearson correlation coefficient and meta-regression. Results: Fifty-two studies (62,385 patients) were included. Primary weighted analysis conducted at the last assessment showed a large significant negative correlation (r, -0.68 [95% confidence interval (CI); -0.77, -0.57]) between trough FEV 1 and SGRQ. Improvement of 100 mL in trough FEV 1 corresponded to a 5.9 point reduction in SGRQ. Similarly, a reduction of 4 points on SGRQ corresponded to 40 mL improvement in trough FEV 1 ( p <0.001). The weighted correlation coefficients of trough FEV 1 with TDI, exacerbation rate (all) and exacerbation rate (moderate/severe) at last assessment point were 0.57, -0.69 and -0.57, respectively (all p <0.05). For the analyses excluding placebo groups, the correlations of FEV 1 with SGRQ and TDI were lower but significant. Conclusions: A strong association exists between changes in spirometric measurements and changes in PROs.

NETosing Neutrophils Activate Complement Both on Their Own NETs and Bacteria via Alternative and Non-alternative Pathways

PubMed Central

Yuen, Joshua; Pluthero, Fred G.; Douda, David N.; Riedl, Magdalena; Cherry, Ahmed; Ulanova, Marina; Kahr, Walter H. A.; Palaniyar, Nades; Licht, Christoph

2016-01-01

Neutrophils deposit antimicrobial proteins, such as myeloperoxidase and proteases on chromatin, which they release as neutrophil extracellular traps (NETs). Neutrophils also carry key components of the complement alternative pathway (AP) such as properdin or complement factor P (CFP), complement factor B (CFB), and C3. However, the contribution of these complement components and complement activation during NET formation in the presence and absence of bacteria is poorly understood. We studied complement activation on NETs and a Gram-negative opportunistic bacterial pathogen Pseudomonas aeruginosa (PA01, PAKwt, and PAKgfp). Here, we show that anaphylatoxin C5a, formyl-methionyl-leucyl-phenylalanine (fMLP) and phorbol myristate acetate (PMA), which activates NADPH oxidase, induce the release of CFP, CFB, and C3 from neutrophils. In response to PMA or P. aeruginosa, neutrophils secrete CFP, deposit it on NETs and bacteria, and induce the formation of terminal complement complexes (C5b–9). A blocking anti-CFP antibody inhibited AP-mediated but not non-AP-mediated complement activation on NETs and P. aeruginosa. Therefore, NET-mediated complement activation occurs via both AP- and non AP-based mechanisms, and AP-mediated complement activation during NETosis is dependent on CFP. These findings suggest that neutrophils could use their “AP tool kit” to readily activate complement on NETs and Gram-negative bacteria, such as P. aeruginosa, whereas additional components present in the serum help to fix non-AP-mediated complement both on NETs and bacteria. This unique mechanism may play important roles in host defense and help to explain specific roles of complement activation in NET-related diseases. PMID:27148258

Enriched continental flood basalts from depleted mantle melts: modeling the lithospheric contamination of Karoo lavas from Antarctica

NASA Astrophysics Data System (ADS)

Heinonen, Jussi S.; Luttinen, Arto V.; Bohrson, Wendy A.

2016-01-01

Continental flood basalts (CFBs) represent large-scale melting events in the Earth's upper mantle and show considerable geochemical heterogeneity that is typically linked to substantial contribution from underlying continental lithosphere. Large-scale partial melting of the cold subcontinental lithospheric mantle and the large amounts of crustal contamination suggested by traditional binary mixing or assimilation-fractional crystallization models are difficult to reconcile with the thermal and compositional characteristics of continental lithosphere, however. The well-exposed CFBs of Vestfjella, western Dronning Maud Land, Antarctica, belong to the Jurassic Karoo large igneous province and provide a prime locality to quantify mass contributions of lithospheric and sublithospheric sources for two reasons: (1) recently discovered CFB dikes show isotopic characteristics akin to mid-ocean ridge basalts, and thus help to constrain asthenospheric parental melt compositions and (2) the well-exposed basaltic lavas have been divided into four different geochemical magma types that exhibit considerable trace element and radiogenic isotope heterogeneity (e.g., initial ɛ Nd from -16 to +2 at 180 Ma). We simulate the geochemical evolution of Vestfjella CFBs using (1) energy-constrained assimilation-fractional crystallization equations that account for heating and partial melting of crustal wall rock and (2) assimilation-fractional crystallization equations for lithospheric mantle contamination by using highly alkaline continental volcanic rocks (i.e., partial melts of mantle lithosphere) as contaminants. Calculations indicate that the different magma types can be produced by just minor (1-15 wt%) contamination of asthenospheric parental magmas by melts from variable lithospheric reservoirs. Our models imply that the role of continental lithosphere as a CFB source component or contaminant may have been overestimated in many cases. Thus, CFBs may represent major juvenile crustal growth events rather than just recycling of old lithospheric materials.

Molecular epidemiology of Streptococcus agalactiae isolated from mastitis in Brazilian dairy herds.

PubMed

Carvalho-Castro, Glei A; Silva, Juliana R; Paiva, Luciano V; Custódio, Dircéia A C; Moreira, Rafael O; Mian, Glaucia F; Prado, Ingrid A; Chalfun-Junior, Antônio; Costa, Geraldo M

Streptococcus agalactiae is one of the most common pathogens leading to mastitis in dairy herds worldwide; consequently, the pathogen causes major economic losses for affected farmers. In this study, multilocus sequence typing (MLST), genotypic capsular typing by multiplex polymerase chain reaction (PCR), and virulence gene detection were performed to address the molecular epidemiology of 59 bovine (mastitis) S. agalactiae isolates from 36 dairy farms located in the largest milk-producing mesoregions in Brazil (Minas Gerais, São Paulo, Paraná, and Pernambuco). We screened for the virulence genes bac, bca, bibA, cfb, hylB, fbsA, fbsB, PI-1, PI-2a, and PI-2b, which are associated with adhesion, invasion, tissue damage, and/or immune evasion. Furthermore, five capsular types were identified (Ia, Ib, II, III, and IV), and a few isolates were classified as non-typeable (NT). MLST revealed the following eight sequence types (STs): ST-61, ST-67, ST-103, ST-146, ST-226, ST-314, and ST-570, which were clustered in five clonal complexes (CC64, CC67, CC103, CC17, and CC314), and one singleton, ST-91. Among the virulence genes screened in this study, PI-2b, fbsB, cfb, and hylB appear to be the most important during mastitis development in cattle. Collectively, these results establish the molecular epidemiology of S. agalactiae isolated from cows in Brazilian herds. We believe that the data presented here provide a foundation for future research aimed at developing and implementing new preventative and treatment options for mastitis caused by S. agalactiae. Copyright © 2017 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

Relationship Between FEV1 and Patient-Reported Outcomes Changes: Results of a Meta-Analysis of Randomized Trials in Stable COPD

PubMed Central

de la Loge, Christine; Tugaut, Béatrice; Fofana, Fatoumata; Lambert, Jérémy; Hennig, Michael; Tschiesner, Uta; Vahdati-Bolouri, Mitra; Segun Ismaila, Afisi; Suresh Punekar, Yogesh

2016-01-01

Background: This meta-analysis assessed the relationship between change from baseline (CFB) in spirometric measurements (trough forced expiratory volume in 1 second [FEV1] and FEV1 area under the curve [AUC]) and patient-reported outcomes (St. George’s Respiratory Questionnaire total score [SGRQ] CFB, Transition Dyspnea Index [TDI] and exacerbation rates) after 6-12 months’ follow-up, using study treatment-group level data. Methods: A systematic literature search was performed for randomized controlled trials of ≥24 weeks duration in adults with chronic obstructive pulmonary disease (COPD). Studies reporting ≥1 spirometric measurement and ≥1 patient-reported outcome (PRO) at baseline and at study endpoint were selected. The relationships between PROs and spirometric endpoints were assessed using Pearson correlation coefficient and meta-regression. Results: Fifty-two studies (62,385 patients) were included. Primary weighted analysis conducted at the last assessment showed a large significant negative correlation (r, −0.68 [95% confidence interval (CI); −0.77, −0.57]) between trough FEV1 and SGRQ. Improvement of 100 mL in trough FEV1 corresponded to a 5.9 point reduction in SGRQ. Similarly, a reduction of 4 points on SGRQ corresponded to 40 mL improvement in trough FEV1 (p<0.001). The weighted correlation coefficients of trough FEV1 with TDI, exacerbation rate (all) and exacerbation rate (moderate/severe) at last assessment point were 0.57, -0.69 and -0.57, respectively (all p<0.05). For the analyses excluding placebo groups, the correlations of FEV1 with SGRQ and TDI were lower but significant. Conclusions: A strong association exists between changes in spirometric measurements and changes in PROs. PMID:28848877

Celecoxib restores angiogenic factor expression at the maternal-fetal interface in the BPH/5 mouse model of preeclampsia.

PubMed

Reijnders, Dorien; Liu, Chin-Chi; Xu, Xinjing; Zhao, Anna M; Olson, Kelsey N; Butler, Scott D; Douglas, Nataki C; Sones, Jenny L

2018-05-01

Preeclampsia (PE), a hypertensive disease of pregnancy, is a leading cause of fetal and maternal morbidity/mortality. Early angiogenic and inflammatory disturbances within the placenta are thought to underlie the development of the maternal PE syndrome and poor pregnancy outcomes. However, the exact etiology remains largely unknown. Here, we use the BPH/5 mouse model of PE to elucidate the way in which inflammation early in pregnancy contributes to abnormal expression of angiogenic factors at the maternal-fetal interface. We have previously described improvement in maternal hypertension and fetal growth restriction in this model after treatment with the anti-inflammatory cyclooxygenase-2 (Cox2) specific inhibitor celecoxib. To further characterize the mechanisms by which celecoxib improves poor pregnancy outcomes in BPH/5 mice, we determined expression of angiogenic factors and complement pathway components after celecoxib. In BPH/5 implantation sites there was increased hypoxia inducible factor-1α ( Hif1α), heme oxygenase-1 ( Ho-1), and stem cell factor ( Scf) mRNA concomitant with elevated prostaglandin synthase 2 ( Ptgs2), encoding Cox2, and elevated VEGF protein. Angiopoietin 1 ( Ang1), tunica interna endothelial cell kinase-2 receptor ( Tie2), complement factor 3 ( C3), and complement factor B ( CfB) were increased in midgestation BPH/5 placentae. Whereas BPH/5 expression levels of VEGF, Ang1, and Tie2 normalized after celecoxib, placental C3 and CfB mRNA remained unchanged. However, celecoxib did reduce the pregnancy-specific circulating soluble fms-like tyrosine kinase-1 (sFlt-1) rise in BPH/5 mice at midgestation. These data show that elevated Cox2 during implantation contributes to placental angiogenic factor imbalances in the BPH/5 mouse model of PE.

Not just a sum of its parts: How tasks of the theory of mind scale relate to executive function across time.

PubMed

Doenyas, Ceymi; Yavuz, H Melis; Selcuk, Bilge

2018-02-01

There is a well-established relationship between theory of mind (ToM) and executive function (EF) during the preschool years. However, less is known about the concurrent and longitudinal relations between EF and specific tasks tapping different aspects of ToM. The current study investigated the ToM-EF relationship across 1 year in 3- to 5-year-old Turkish children using the ToM battery of Wellman and Liu (2004), which measures understanding of diverse desires (DD), diverse beliefs (DB), knowledge access (KA), contents false belief (CFB), explicit false belief (EFB), and hidden emotion (HE). This battery has not yet been used in its entirety to test the predictive relations between ToM and EF. We used peg-tapping and day-night tasks to measure EF. Our sample comprised 150 Turkish preschool children (69 girls) aged 36-60 months at Time 1 (T1) and 49-73 months at Time 2 (T2). Using the ToM composite with all six tasks, when child's age, receptive language, and T1 ability level (EF or ToM) were controlled, T1 EF significantly predicted T2 ToM, whereas T1 ToM did not predict T2 EF. Among DD, DB, KA, false belief understanding (FBU: the composite score of CFB and EFB), and HE, only KA and FBU were significantly associated with EF at T1 and T2. Further regression analyses showed that KA did not have a predictive relationship with EF. Instead, FBU drove the predictive EF-ToM relationship across time. Thus, in Turkish children, earlier EF predicts later ToM, but especially the FBU component, in this well-validated battery. Copyright © 2017. Published by Elsevier Inc.

Gun Propellant Residues Dispersed from Static Artillery Firings of LG1 Mark 2 and C3 105-mm Howitzers

DTIC Science & Technology

2008-10-01

nitroglycerine (NG). In this study, aluminium witness plates were placed in front of the muzzle of the gun to collect residues propelled in the environment...témoins en aluminium ont été placées en face de la bouche du canon pour récolter les résidus de tirs propulsés dans l’environnement. Les plaques ont été...the Mark II and C3 105-mm howitzers, during an artillery exercise performed from May 9 to May 12, 2005 at CFB Gagetown in New-Brunswick. Aluminium

Development of an E-Prime Based Computer Simulation of an Interactive Human Rights Violation Negotiation Script (Developpement d’un Programme de Simulation par Ordinateur Fonde sur le Logiciel E Prime pour la Negociation Interactive en cas de Violation des Droits de la Personne)

DTIC Science & Technology

2010-12-01

Base ( CFB ) Kingston. The computer simulation developed in this project is intended to be used for future research and as a possible training platform...DRDC Toronto No. CR 2010-055 Development of an E-Prime based computer simulation of an interactive Human Rights Violation negotiation script...Abstract This report describes the method of developing an E-Prime computer simulation of an interactive Human Rights Violation (HRV) negotiation. An

Dynamic Modification of Pore Opening of SAPO-34 by Adsorbed Surface Methoxy Species during Induction of Catalytic Methanol-to-Olefins Reactions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lo, Benedict T W.; Ye, Lin; Change, G.G. Z.

Here, we report that the pore opening of SAPO-34 can be significantly modified by an adsorbed surface methoxy species during induction of the catalytic methanol-to-olefins process, which offers molecular sieving properties due to physical obstacle of the methoxy group and its adsorption modification to other hydrocarbons. X-ray powder diffraction and Rietveld refinement clearly reveal that the adsorbed single carbon atom as the methoxy group is dynamically created from methanol dehydration on a Brønsted acid site in close proximity to the pore windows. As a result, industrial desirable smaller olefins such as ethylene and propylene can be favourably made at themore » expenses of higher olefins. The structures and fundamental understanding in alteration in the olefins selectivity during induction may allow rational optimisation in catalytic performance under the complex fluidisation conditions.« less

Analogue modelling of caprock failure and sediment mobilisation due to pore fluid overpressure in shallow reservoirs

NASA Astrophysics Data System (ADS)

Warsitzka, Michael; Kukowski, Nina; May, Franz

2017-04-01

Injection of CO2 in geological formations may cause excess pore fluid pressure by enhancing the fluid volume in the reservoir rock and by buoyancy-driven flow. If sediments in the reservoir and the caprock are undercompacted, pore fluid overpressure can lead to hydro-fractures in the caprock and fluidisation of sediments. Eventually, these processes trigger the formation of pipe structures, gas chimneys, gas domes or sand injections. Generally, such structures serve as high permeable pathways for fluid migration through a low-permeable seal layer and have to be considered in risk assessment or modelling of caprock integrity of CO2 storage sites. We applied scaled analogue experiments to characterise and quantify mechanisms determining the onset and migration of hydro-fractures in a low-permeable, cohesive caprock and fluidisation of unconsolidated sediments of the reservoir layer. The caprock is simulated by different types of cohesive powder. The reservoir layer consists of granulates with small particle density. Air injected through the base of the experiment and additionally through a single needle valve reaching into the analogue material is applied to generate fluid pressure within the materials. With this procedure, regional fluid pressure increase or a point-like local fluid pressure increase (e.g. injection well), respectively, can be simulated. The deformation in the analogue materials is analysed with a particle tracking imaging velocimetry technique. Pressure sensors at the base of the experiment and in the needle valve record the air pressure during an experimental run. The structural evolution observed in the experiments reveal that the cohesive cap rock first forms a dome-like anticline. Extensional fractures occur at the hinges of the anticline. A further increase of fluid pressure causes a migration of this fractures towards the surface, which is followed by intrusion of reservoir material into the fractures and the collapse of the anticline. The breakthrough of the fractures at the surface is accompanied by a significant drop of air pressure at the base of the analogue materials. The width of the dome shaped uplift is narrower and the initiating fluid pressure in the needle valve is lower, if the fluid pressure at the base of the experiment is larger. The experimental outcomes help to evaluate if the injection of CO2 into a reservoir potentially provokes initiation or reactivation of fractures and sediment mobilisation structures.

Computer simulation of an Aircraft Seat and Occupant(s) in a Crash Environment - Program SOM-LA/SOM-TA (User Manual)

DTIC Science & Technology

1991-05-01

INFORMATION 8 2.7.1 Rigid Seat Option 8 2.7.2 Simplified Energy-Absorbing Seal Option 8 2.7.3 Finite Elemrent Structural Analysis 8 3.0 PROGRAM OUTPUT DATA 10...62000. 0,0 0.0 00035000 244130- STFEL 000330].0 7 .120E-4 29.086 163000. 6. CFb 180000. 0. 𔃻 00034010 174000. 81000, 0.0 0.0 00035010 8 0 0.4347 0.3028...0.0 IRoiational damping in neck. (Ub .’c). IIUCEIFjI.__Qti: Dimensions of seaL model as shown in Figure A-8. _45Y 0 V14567 ’TT2 l-8-7-T345367 0 1

Polymorphisms in ARMS2/HTRA1 and Complement Genes and Age-Related Macular Degeneration in India: Findings from the INDEYE Study

PubMed Central

Sundaresan, Periasamy; Vashist, Praveen; Ravindran, Ravilla D.; Shanker, Ashwini; Nitsch, Dorothea; Nonyane, Bareng A. S.; Smeeth, Liam; Chakravarthy, Usha; Fletcher, Astrid E.

2012-01-01

Purpose. Association between genetic variants in complement factor H (CFH), factor B (CFB), component 2 (C2), and in the ARMS2/HTRA1 region with age-related macular degeneration (AMD) comes mainly from studies of European ancestry and case-control studies of late-stage disease. We investigated associations of both early and late AMD with these variants in a population-based study of people aged 60 years and older in India. Methods. Fundus images were graded using the Wisconsin Age-Related Maculopathy Grading System and participants assigned to one of four mutually exclusive stages based on the worse affected eye (0 = no AMD, 1–3 = early AMD, 4 = late AMD). Multinomial logistic regression was used to derive risk ratios (RR) accounting for sampling method and adjusting for age, sex, and study center. Results. Of 3569 participants, 53.2% had no signs of AMD, 45.6% had features of early AMD, and 1.2% had late AMD. CFH (rs1061170), C2 (rs547154), or CFB (rs438999) was not associated with early or late AMD. In the ARMS2 locus, rs10490924 was associated with both early (adjusted RR 1.22, 95% confidence interval [CI]: 1.13–1.33, P < 0.0001) and late AMD (adjusted RR 1.81, 95% CI: 1.15–2.86; P = 0.01); rs2672598 was associated only with early AMD (adjusted RR 1.12, 95% CI: 1.02–1.23; P = 0.02); rs10490923 was not associated with early or late AMD. Conclusions. Two variants in ARMS2/HTRA1 were associated with increased risk of early AMD, and for one of these, the increased risk was also evident for late AMD. The study provides new insights into the role of these variants in early stages of AMD in India. PMID:23060141

Comparison of the Decomposition VOC Profile during Winter and Summer in a Moist, Mid-Latitude (Cfb) Climate

PubMed Central

Forbes, Shari L.; Perrault, Katelynn A.; Stefanuto, Pierre-Hugues; Nizio, Katie D.; Focant, Jean-François

2014-01-01

The investigation of volatile organic compounds (VOCs) associated with decomposition is an emerging field in forensic taphonomy due to their importance in locating human remains using biological detectors such as insects and canines. A consistent decomposition VOC profile has not yet been elucidated due to the intrinsic impact of the environment on the decomposition process in different climatic zones. The study of decomposition VOCs has typically occurred during the warmer months to enable chemical profiling of all decomposition stages. The present study investigated the decomposition VOC profile in air during both warmer and cooler months in a moist, mid-latitude (Cfb) climate as decomposition occurs year-round in this environment. Pig carcasses (Sus scrofa domesticus L.) were placed on a soil surface to decompose naturally and their VOC profile was monitored during the winter and summer months. Corresponding control sites were also monitored to determine the natural VOC profile of the surrounding soil and vegetation. VOC samples were collected onto sorbent tubes and analyzed using comprehensive two-dimensional gas chromatography – time-of-flight mass spectrometry (GC×GC-TOFMS). The summer months were characterized by higher temperatures and solar radiation, greater rainfall accumulation, and comparable humidity when compared to the winter months. The rate of decomposition was faster and the number and abundance of VOCs was proportionally higher in summer. However, a similar trend was observed in winter and summer demonstrating a rapid increase in VOC abundance during active decay with a second increase in abundance occurring later in the decomposition process. Sulfur-containing compounds, alcohols and ketones represented the most abundant classes of compounds in both seasons, although almost all 10 compound classes identified contributed to discriminating the stages of decomposition throughout both seasons. The advantages of GC×GC-TOFMS were demonstrated for detecting and identifying trace levels of VOCs, particularly ethers, which are rarely reported as decomposition VOCs. PMID:25412504

Development of a single-dose recombinant CAMP factor entrapping poly(lactide-co-glycolide) microspheres-based vaccine against Streptococcus agalactiae.

PubMed

Liu, Gang; Yin, Jinhua; Barkema, Herman W; Chen, Liben; Shahid, Muhammad; Szenci, Otto; De Buck, Jeroen; Kastelic, John P; Han, Bo

2017-03-01

Streptococcus agalactiae is an important contagious bovine mastitis pathogen. Although it is well controlled and even eradicated in most Northern European and North American dairy herds, the prevalence of this pathogen remains very high in China. However, research on development of a vaccine against S. agalactiae mastitis is scarce. The aims of the present study were to: (1) develop a single-dose vaccine against S. agalactiae based on poly(lactic-co-glycolic acid) (PLGA) microspheres (MS) encapsulated CAMP factor, a conserved virulent protein encoded by S. agalactiae's cfb gene; and (2) evaluate its immunogenicity and protective efficacy in a mouse model. The cfb gene was cloned and expressed in a recombinant Escherichia coli strain Trans1-T1. The CAMP factor was tested to determine a safe dose range and then encapsulated in MS of PLGA (50:50) to assess its release pattern in vitro and immune reaction in vivo. Furthermore, a mouse model and a histopathological assay were developed to evaluate bacterial burden and vaccine efficacy. In the low dosage range (<100μg), CAMP factor had no obvious toxicity in mice. The release pattern in vitro was characterized by an initial burst release (44%), followed by a sustained and slower release over 7wk. In mice immunized with either pure CAMP factor protein or PLGA-CAMP, increased antibody titers were detected in the first 2wk, whereas only PLGA-CAMP immunization induced a sustained increase of antibody titers. In mice vaccinated with PLGA-CAMP, mortality and bacteria counts were lower (compared to a control group) after S. agalactiae challenge. Additionally, no pathological lesions were detected in the vaccinated group. Therefore, PLGA-CAMP conferred protective efficacy against S. agalactiae in our mouse model, indicating its potential as a vaccine against S. agalactiae mastitis. Furthermore, the slow-release kinetics of PLGA MS warranted optimism for development of a single-dose vaccine. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

Photoluminescence characteristics of Eu2O3 doped calcium fluoroborate glasses

NASA Astrophysics Data System (ADS)

Krishnapuram, Pavani; Jakka, Suresh Kumar; Thummala, Chengaiah; Lalapeta, Rama Moorthy

2012-11-01

The present work reports the preparation and characterization of calcium fluoroborate (CFB) glasses doped with different concentrations of Eu2O3. The spectroscopic free-ion parameters are evaluated from the experimentally observed energy levels of Eu3+ ions in CFB glasses by using the free-ion Hamiltonian model (HFI). The phenomenological Judd-Ofelt (J-O) parameters, Ω2, Ω4 and Ω6, are evaluated from the intensities of Eu3+ ion absorption bands by various constraints. From these J-O parameters (Ωλ), the radiative parameters such as transition probabilities (AR), branching ratios (βR), stimulated emission cross sections (σe) and radiative lifetimes (τR) are evaluated for 5D→7(4fASO+αL(L+1)+βG(G2)+γG(R7)+∑j=0,2,4 Mjmj+∑k=2,4,6 PKpK where Eavg includes the kinetic energy of the electrons and their interaction with the nucleus. It shifts only the barycentre of the whole 4fN configuration. Fk (k = 2, 4, 6) are free electron repulsion parameters, ξ4f is the spin-orbit coupling constant, α, β and γ are the three interaction parameters, Mj (j = 0, 2, 4) and Pk (k = 2, 4, 6) are magnetic interaction parameters. Among all the interactions, Fk and ξ4f are the main ones which give rise to the 2LJ levels. The rest only make corrections in the energies of these levels without removing their degeneracy. The parametric fits have been carried out as has been done in our earlier work [16]. The quality of the parametric fit is generally described in terms of the root mean square (rms) deviation, σrms between the experimental and calculated energies by the relation σrms=√{{∑}/{i=1N(Eiexp-Eical)2N}} where Eiexp and Eical are the experimental and calculated energies, respectively, for level 'i' and N denotes the total number of levels included in the energy level fit.

Comparison of the decomposition VOC profile during winter and summer in a moist, mid-latitude (Cfb) climate.

PubMed

Forbes, Shari L; Perrault, Katelynn A; Stefanuto, Pierre-Hugues; Nizio, Katie D; Focant, Jean-François

2014-01-01

The investigation of volatile organic compounds (VOCs) associated with decomposition is an emerging field in forensic taphonomy due to their importance in locating human remains using biological detectors such as insects and canines. A consistent decomposition VOC profile has not yet been elucidated due to the intrinsic impact of the environment on the decomposition process in different climatic zones. The study of decomposition VOCs has typically occurred during the warmer months to enable chemical profiling of all decomposition stages. The present study investigated the decomposition VOC profile in air during both warmer and cooler months in a moist, mid-latitude (Cfb) climate as decomposition occurs year-round in this environment. Pig carcasses (Sus scrofa domesticus L.) were placed on a soil surface to decompose naturally and their VOC profile was monitored during the winter and summer months. Corresponding control sites were also monitored to determine the natural VOC profile of the surrounding soil and vegetation. VOC samples were collected onto sorbent tubes and analyzed using comprehensive two-dimensional gas chromatography--time-of-flight mass spectrometry (GC × GC-TOFMS). The summer months were characterized by higher temperatures and solar radiation, greater rainfall accumulation, and comparable humidity when compared to the winter months. The rate of decomposition was faster and the number and abundance of VOCs was proportionally higher in summer. However, a similar trend was observed in winter and summer demonstrating a rapid increase in VOC abundance during active decay with a second increase in abundance occurring later in the decomposition process. Sulfur-containing compounds, alcohols and ketones represented the most abundant classes of compounds in both seasons, although almost all 10 compound classes identified contributed to discriminating the stages of decomposition throughout both seasons. The advantages of GC × GC-TOFMS were demonstrated for detecting and identifying trace levels of VOCs, particularly ethers, which are rarely reported as decomposition VOCs.

Environmental Changes Associated With Deccan Volcanism: evidences from the red bole record

NASA Astrophysics Data System (ADS)

Nikhil, Sharma; Valentin, Sordet; Thierry, Adatte; Gerta, Keller; Eric, Font; Blair, Schoene; Kyle, Samperton; Syed, Khadri

2017-04-01

Recent studies indicate that the bulk (80%) of Deccan trap eruptions occurred over a relatively short time interval in magnetic polarity C29r. U-Pb zircon geochronology shows that the main phase-2 began 250 ky before the Cretaceous-Tertiary (KT) mass extinction and continued into the early Danian suggesting a cause-and-effect relationship. Closer to the eruption center, the lava flows are generally separated by red weathered horizons known as red boles that mark quiescent periods between basalt flows. A typical red bole begins with the fresh underlying basalt and evolves into weathered basalt, then, a layer of basalt in a rounded shape called 'bole' surrounded by clays at the top, which is overlain by the next lava flow. Red boles have increasingly attracted the attention of researchers to understand the climatic and paleoenvironmental impact of Continental Flood Basalts (CFB). Recent advances in U-Pb dating of Deccan lava flows, studies of weathering patterns and paleoclimatic information gained from multiproxy analyses of red bole beds (e.g., lithology, mineralogy, geochemistry) yield crucial evidence of environmental changes triggered by volcanic activity. Red boles consist mainly of red silty clays characterized by concentrations of immobile elements such as Al and Fe3+ ions that are typical of paleo-laterites, which probably developed during the short periods of weathering between eruptions. Clay minerals consist mostly of smectite suggesting semi-arid monsoonal conditions. At least 30 thick red bole layers are present in C29r below the KT boundary between lava flows of phase-2 that erupted over a time span of about 250 ky. The short duration exposures of these red boles are reflected in the mineralogical and geochemical data that indicate rapid weathering (high CIA) linked to increasing acid rains. ∂D and ∂18O measured on smectite clays from the red boles approximate the meteoric water composition that prevailed during Deccan eruptions. Isotopic data from red boles deposited through the main phase-2 suggest significant and rapid changes in rainfall intensity and/or altitude linked to the accumulation of a 3100m thick basalt pile that erupted over a short period of time.

Development of a two-fluid drag law for clustered particles using direct numerical simulation and validation through experiments

NASA Astrophysics Data System (ADS)

Abbasi Baharanchi, Ahmadreza

This dissertation focused on development and utilization of numerical and experimental approaches to improve the CFD modeling of fluidization flow of cohesive micron size particles. The specific objectives of this research were: (1) Developing a cluster prediction mechanism applicable to Two-Fluid Modeling (TFM) of gas-solid systems (2) Developing more accurate drag models for Two-Fluid Modeling (TFM) of gas-solid fluidization flow with the presence of cohesive interparticle forces (3) using the developed model to explore the improvement of accuracy of TFM in simulation of fluidization flow of cohesive powders (4) Understanding the causes and influential factor which led to improvements and quantification of improvements (5) Gathering data from a fast fluidization flow and use these data for benchmark validations. Simulation results with two developed cluster-aware drag models showed that cluster prediction could effectively influence the results in both the first and second cluster-aware models. It was proven that improvement of accuracy of TFM modeling using three versions of the first hybrid model was significant and the best improvements were obtained by using the smallest values of the switch parameter which led to capturing the smallest chances of cluster prediction. In the case of the second hybrid model, dependence of critical model parameter on only Reynolds number led to the fact that improvement of accuracy was significant only in dense section of the fluidized bed. This finding may suggest that a more sophisticated particle resolved DNS model, which can span wide range of solid volume fraction, can be used in the formulation of the cluster-aware drag model. The results of experiment suing high speed imaging indicated the presence of particle clusters in the fluidization flow of FCC inside the riser of FIU-CFB facility. In addition, pressure data was successfully captured along the fluidization column of the facility and used as benchmark validation data for the second hybrid model developed in the present dissertation. It was shown the second hybrid model could predict the pressure data in the dense section of the fluidization column with better accuracy.

Giant fluctuations and structural effects in a flocking epithelium

NASA Astrophysics Data System (ADS)

Giavazzi, Fabio; Malinverno, Chiara; Corallino, Salvatore; Ginelli, Francesco; Scita, Giorgio; Cerbino, Roberto

2017-09-01

Epithelial cells cultured in a monolayer are very motile in isolation but reach a near-jammed state when mitotic division increases their number above a critical threshold. We have recently shown that a monolayer can be reawakened by over-expression of a single protein, RAB5A, a master regulator of endocytosis. This reawakening of motility was explained in terms of a flocking transition that promotes the emergence of a large-scale collective migratory pattern. Here we focus on the impact of this reawakening on the structural properties of the monolayer. We find that the unjammed monolayer is characterised by a fluidisation at the single cell level, and by enhanced non-equilibrium large-scale number fluctuations at a larger length scale. Also, with the help of numerical simulations, we trace back the origin of these fluctuations to the self-propelled active nature of the constituents, and to the existence of a local alignment mechanism, leading to the spontaneous breaking of the orientational symmetry.

Some open issues in the analysis of the storage and migration properties of fractured carbonate reservoirs

NASA Astrophysics Data System (ADS)

Agosta, Fabrizio

2017-04-01

Underground CO2 storage in depleted hydrocarbon reservoirs may become a common practice in the future to lower the concentration of greenhouse gases in the atmosphere. Results from the first experiments conducted in carbonate rocks, for instance the Lacq integrated CCS Pilot site, SW France, are quite exciting. All monitored parameters, such as the CO2 concentration at well sites, well pressures, cap rock integrity and environmental indicators show the long-term integrity of this type of geological reservoirs. Other positive news arise from the OXY-CFB-300 Compostilla Project, NW Spain, where most of the injected CO2 dissolved into the formation brines, suggesting the long-term security of this method. However, in both cases, the CO2- rich fluids partially dissolved the carbonate minerals during their migration through the fractured reservoir, modifying the overall pore volume and pressure regimes. These results support the growing need for a better understanding of the mechanical behavior of carbonate rocks over geological time of scales. In fact, it is well known that carbonates exhibit a variety of deformation mechanisms depending upon many intrinsic factors such as composition, texture, connected pore volume, and nature of the primary heterogeneities. Commonly, tight carbonates are prone to opening-mode and/or pressure solution deformation. The interplay between these two mechanisms likely affects the petrophysical properties of the fault damage zones, which form potential sites for CO2 storage due to their high values of both connected porosity and permeability. On the contrary, cataclastic deformation produces fault rocks that often form localized fluid barriers for cross-fault fluid flow. Nowadays, questions on the conditions of sealing/leakage of carbonate fault rocks are still open. In particular, the relative role played by bulk crushing, chipping, cementation, and pressure solution on connected porosity of carbonate fault rocks during structural evolution and diagenesis is not determined yet. Differently, porous rocks are mainly affected by deformation banding. The latter process involves the collapse of primary porosity within narrow bands, which often localize into well-developed clusters. Currently, researchers focus on the assessment of the 3D pore geometry of the shear bands, which may act as possible sites for residual C02 trapping. The fault-bounded rock volumes are mainly crosscut by background fractures. These diffuse fractures are often compartmentalized into discrete mechanical units, which are bounded by primary heterogeneities such as bed interfaces and transgressive erosional surfaces. Moreover, bed-parallel pressure solution seams, structural elements that commonly form in limestone rocks during burial diagenesis, can also act as mechanical interfaces during growth of background fractures. However, early embrittlement of carbonates was also documented, suggesting to further investigate their diagenetic evolution to determine the conditions at which the latter phenomenon takes place. Results could shed new lights into the storage properties and, hence, the amount of CO2 that can be securely stored within significant volumes of fractured carbonates in the underground.

Latest in tire burning

DOE Office of Scientific and Technical Information (OSTI.GOV)

Betzig, H.M.

1996-12-31

On September 26, Cris Lombardi and I presented a paper at the ARIPPA. The economic and environmental advantages available to CFB operators through the firing of tire-derived fuel (TDF) are discussed. The bottom line savings to the operation can be significant. It is believed that a regional scrap tire processing facility, capable of making properly-sized fuel, can be supported in Pennsylvania. An effort to develop such an operation is described. The technology for shredding and sizing TDF is well-proven. The proper equipment has been identified and reliable sources of scrap tires have been located. What is needed is to establishmore » a certain minimum annual TDF usage so that fuel user permit modification activity can begin. Data are presented on the production and use of TDF.« less

A CFD study of gas-solid jet in a CFB riser flow

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Tingwen; Guenther, Chris

2012-03-01

Three-dimensional high-resolution numerical simulations of a gas–solid jet in a high-density riser flow were conducted. The impact of gas–solid injection on the riser flow hydrodynamics was investigated with respect to voidage, tracer mass fractions, and solids velocity distribution. The behaviors of a gas–solid jet in the riser crossflow were studied through the unsteady numerical simulations. Substantial separation of the jetting gas and solids in the riser crossflow was observed. Mixing of the injected gas and solids with the riser flow was investigated and backmixing of gas and solids was evaluated. In the current numerical study, both the overall hydrodynamics ofmore » riser flow and the characteristics of gas–solid jet were reasonably predicted compared with the experimental measurements made at NETL.« less

Dykes as Tracers of Continental Break-up: Argon Geochronology of Mesozoic Flood Basalts of Western Dronning Maud Land, Antarctica

NASA Astrophysics Data System (ADS)

Fazel, A.; Kelley, S. P.; Leat, P. T.; Hawkesworth, C.

2003-04-01

The British Antarctic Survey MAMOG Project (Magmatism as A Monitor Of Gondwana break up processes) is investigating the mantle processes that resulted in the eruption of the Karoo-Dronning Maud Land CFB suite and its importance in our understanding of the initial stages of Gondwana break-up. One of the problems of understanding the 180Ma continental flood basalts is knowing their precise age. Since they are erupted through more ancient (1000Ma) rocks we have to use the Ar-Ar dating technique to determine whether they are related to the continental break-up or are part of some older event. In addition, we have analysed the chemistry of the dykes and can relate them to several chemical types, the challenge is to test if dykes with similar chemistry all erupted at the same time. It has been suggested that many of the Jurassic dykes in western DML fed the CFB suite that is higher in the volcanic pile. We have found dykes of different ages in the Kirwanveggen and Ahlmannryggen regions of western DML. Although more work needs to be done, we now have mounting evidence to suggest that episodes of chemically similar magmatism in DML stretched from 1000-180Ma with some events separated by hundreds of millions of years implying a lithospheric mantle control on magma composition. The precise ages for the dykes are slightly younger than the accepted ages for the South African Karoo province. In addition to determining the ages of dyke intrusions, a high spatial resolution UV laser has been used to measure argon loss from diorite host rocks adjacent to the dykes. Progressive heating of the country rock during magma emplacement causes argon loss. Thermal modelling of the dykes will allow us to differentiate between various heat loss mechanisms and give an indication of the style, volume and rapidity of magma flow through the dyke. The UV results have shown that some of the dykes were active for long periods probably feeding the surface lava eruptions.

Comparative K-Ar and Ar/Ar dating of Ethiopian and Yemenite Oligocene volcanism: implications for timing and duration of the Ethiopian traps

NASA Astrophysics Data System (ADS)

Coulié, E.; Quidelleur, X.; Gillot, P.-Y.; Courtillot, V.; Lefèvre, J.-C.; Chiesa, S.

2003-02-01

It is now generally accepted that continental flood basalt (CFB) volcanism bears a strong relationship with continental breakup. The Ethiopian Afar plume has been linked to the opening of the Afar depression. Propagation of the Red Sea and Gulf of Aden rifts within the depression, still an ongoing process, has rifted away the Ethiopian and Yemenite trap sequences. They are in some locations more than 2 km thick and comprise a wide range of volcanic products, from tholeiitic basalts, in the lower part, to more acidic material in the upper part. Recent studies have established that the bulk of trap volcanism erupted about 30 Ma ago over a period of 1 Myr in the Ethiopian sections, while ages obtained on the Yemenite sections seem more distributed through time. Here, for the first time in a single study, we present geochronological results obtained for basalts and more evolved products for both Ethiopian and Yemenite traps. This approach eliminates inter-laboratory biases and discrepancies in the ages of standards, and imposes better constraints on the eruptive chronology of this CFB province. In addition, both the K-Ar and 40Ar/ 39Ar techniques have been applied simultaneously, in order to demonstrate that similar ages are indeed obtained for undisturbed samples. The two dating techniques used here yield concordant ages for most samples. On both sides of the Afar depression, our results support that the onset of basaltic volcanism is coeval, with undistinguishable ages of 30.6±0.4 and 30.2±0.4 Ma obtained from Ethiopia and Yemen, respectively. Most of the basaltic lava pile has been erupted in less than 1 Myr, but acidic volcanism seems more spread out through time. It is coeval with basalts in northern Ethiopia but extends to about 26 Ma in Yemen, as already recognized. A younger rhyolitic episode, probably related to the major 20 Ma phase of opening of the Red Sea and Gulf of Aden, as expressed in the Afar depression, is also observed in Yemen and central Ethiopia.

Phylogenetic characterization of microbial communities that reductively dechlorinate TCE based upon a combination of molecular techniques.

PubMed

Richardson, Ruth E; Bhupathiraju, Vishvesh K; Song, Donald L; Goulet, Tanuja A; Alvarez-Cohen, Lisa

2002-06-15

An anaerobic microbial consortium (referred to as ANAS) that reductively dechlorinates trichloroethene (TCE) completely to ethene with the transient production of cisdichloroethene (cDCE) and vinyl chloride was enriched from contaminated soil obtained from Alameda Naval Air Station. ANAS uses lactate as its electron donor and has been functionally stable for over 2 years. Following a brief exposure to oxygen, a subculture (designated VCC) derived from ANAS could dechlorinate TCE only to vinyl chloride with lactate as its electron donor. Three molecular methods were used concurrently to characterize the community structure of ANAS and VCC: clone library construction/clone sequencing, terminal restriction fragment length polymorphism (T-RFLP) analysis, and fluorescent in situ hybridization (FISH) with rRNA probes. The community structure of ANAS did not change significantly over the course of a single feeding/dechlorination cycle, and only minor fluctuations occurred over many feeding cycles spanning the course of 1 year. Clone libraries and T-RFLP analyses suggested that ANAS was dominated by populations belonging to three phylogenetic groups: Dehalococcoides species, Desulfovibrio species, and members of the Clostridiaceae (within the low G + C Gram-positives). FISH results suggest that members of the Cytophaga/Flavobacterium/Bacteroides (CFB) cluster and high G + C Gram-positives (HGCs) were numerically important in ANAS despite their under-representation in the clone libraries. Parallel analyses of VCC samples suggested that Dehalococcoides species and Clostridiaceae were only minor populations in this community. Instead, VCC had increased populations of organisms in the beta and gamma subclasses of the Proteobacteria as well as significant populations of organisms in the CFB cluster. It is possible that symbiotic interactions are occurring between some of ANAS's phylogenetic groups under the enrichment conditions, including interspecies hydrogen transfer from Desulfovibrio species to Dehalococcoides species. However, the nucleic acid-based analyses performed here would need to be supplemented with chemical species data in order to test any hypotheses about functional roles of various community members. Additionally, these results suggest that an organism outside the Dehalococcoides genus may be capable of dechlorinating cDCE to vinyl chloride.

Enrichment of 18O in the mantle sources of the Antarctic portion of the Karoo large igneous province

NASA Astrophysics Data System (ADS)

Heinonen, Jussi S.; Luttinen, Arto V.; Whitehouse, Martin J.

2018-03-01

Karoo continental flood basalt (CFB) province is known for its highly variable trace element and isotopic composition, often attributed to the involvement of continental lithospheric sources. Here, we report oxygen isotopic compositions measured with secondary ion mass spectrometry for hand-picked olivine phenocrysts from 190 to 180 Ma CFBs and intrusive rocks from Vestfjella, western Dronning Maud Land, that form an Antarctic extension of the Karoo province. The Vestfjella lavas exhibit heterogeneous trace element and radiogenic isotope compositions (e.g., ɛ Nd from - 16 to + 2 at 180 Ma) and the involvement of continental lithospheric mantle and/or crust in their petrogenesis has previously been suggested. Importantly, our sample set also includes rare primitive dikes that have been derived from depleted asthenospheric mantle sources ( ɛ Nd up to + 8 at 180 Ma). The majority of the oxygen isotopic compositions of the olivines from these dike rocks (δ18O = 4.4-5.2‰; Fo = 78-92 mol%) are also compatible with such sources. The olivine phenocrysts in the lavas, however, are characterized by notably higher δ18O (6.2-7.5‰; Fo = 70-88 mol%); and one of the dike samples gives intermediate compositions (5.2‒6.1‰, Fo = 83-87 mol%) between the other dikes and the CFBs. The oxygen isotopic compositions do not correlate with radiogenic isotope compositions susceptible to crustal assimilation (Sr, Nd, and Pb) or with geochemical indicators of pyroxene-rich mantle sources. Instead, δ18O correlates positively with enrichments in large-ion lithophile elements (especially K) and 187Os. We suggest that the oxygen isotopic compositions of the Vestfjella CFB olivines primarily record large-scale subduction-related metasomatism of the sub-Gondwanan mantle (base of the lithosphere or deeper) prior to Karoo magmatism. The overall influence of such sources to Karoo magmatism is not known, but, in addition to continental lithosphere, they may be responsible for some of the geochemical heterogeneity observed in the CFBs.

Using multiple bed load measurements: Toward the identification of bed dilation and contraction in gravel-bed rivers

NASA Astrophysics Data System (ADS)

Marquis, G. A.; Roy, A. G.

2012-02-01

This study examines bed load transport processes in a small gravel-bed river (Béard Creek, Québec) using three complementary methods: bed elevation changes between successive floods, bed activity surveys using tags inserted into the bed, and bed load transport rates from bed load traps. The analysis of 20 flood events capable of mobilizing bed material led to the identification of divergent results among the methods. In particular, bed elevation changes were not consistent with the bed activity surveys. In many cases, bed elevation changes were significant (1 to 2 times the D50) even if the bed surface had not been activated during the flood, leading to the identification of processes of bed dilation and contraction that occurred over 10% to 40% of the bed surface. These dynamics of the river bed prevent accurate derivation of bed load transport rates from topographic changes, especially for low magnitude floods. This paper discusses the mechanisms that could explain the dilation and contraction of particles within the bed and their implications in fluvial dynamics. Bed contraction seems to be the result of the winnowing of the fine sediments under very low gravel transport. Bed dilation seems to occur on patches of the bed at the threshold of motion where various processes such as fine sediment infiltration lead to the maintenance of a larger sediment framework volume. Both processes are also influenced by flood history and the initial local bed state and in turn may have a significant impact on sediment transport and morphological changes in gravel-bed rivers.

Functionalised particles using dry powder coating in pharmaceutical drug delivery: promises and challenges.

PubMed

Dahmash, Eman Z; Mohammed, Afzal R

2015-01-01

Production of functionalised particles using dry powder coating is a one-step, environmentally friendly process that paves the way for the development of particles with targeted properties and diverse functionalities. Applying the first principles in physical science for powders, fine guest particles can be homogeneously dispersed over the surface of larger host particles to develop functionalised particles. Multiple functionalities can be modified including: flowability, dispersibility, fluidisation, homogeneity, content uniformity and dissolution profile. The current publication seeks to understand the fundamental underpinning principles and science governing dry coating process, evaluate key technologies developed to produce functionalised particles along with outlining their advantages, limitations and applications and discusses in detail the resultant functionalities and their applications. Dry particle coating is a promising solvent-free manufacturing technology to produce particles with targeted functionalities. Progress within this area requires the development of continuous processing devices that can overcome challenges encountered with current technologies such as heat generation and particle attrition. Growth within this field requires extensive research to further understand the impact of process design and material properties on resultant functionalities.

Ability of bed bug-detecting canines to locate live bed bugs and viable bed bug eggs.

PubMed

Pfiester, Margie; Koehler, Philip G; Pereira, Roberto M

2008-08-01

The bed bug, Cimex lectularius L., like other bed bug species, is difficult to visually locate because it is cryptic. Detector dogs are useful for locating bed bugs because they use olfaction rather than vision. Dogs were trained to detect the bed bug (as few as one adult male or female) and viable bed bug eggs (five, collected 5-6 d after feeding) by using a modified food and verbal reward system. Their efficacy was tested with bed bugs and viable bed bug eggs placed in vented polyvinyl chloride containers. Dogs were able to discriminate bed bugs from Camponotus floridanus Buckley, Blattella germanica (L.), and Reticulitermes flavipes (Kollar), with a 97.5% positive indication rate (correct indication of bed bugs when present) and 0% false positives (incorrect indication of bed bugs when not present). Dogs also were able to discriminate live bed bugs and viable bed bug eggs from dead bed bugs, cast skins, and feces, with a 95% positive indication rate and a 3% false positive rate on bed bug feces. In a controlled experiment in hotel rooms, dogs were 98% accurate in locating live bed bugs. A pseudoscent prepared from pentane extraction of bed bugs was recognized by trained dogs as bed bug scent (100% indication). The pseudoscent could be used to facilitate detector dog training and quality assurance programs. If trained properly, dogs can be used effectively to locate live bed bugs and viable bed bug eggs.

A method for generating double-ring-shaped vector beams

NASA Astrophysics Data System (ADS)

Huan, Chen; Xiao-Hui, Ling; Zhi-Hong, Chen; Qian-Guang, Li; Hao, Lv; Hua-Qing, Yu; Xu-Nong, Yi

2016-07-01

We propose a method for generating double-ring-shaped vector beams. A step phase introduced by a spatial light modulator (SLM) first makes the incident laser beam have a nodal cycle. This phase is dynamic in nature because it depends on the optical length. Then a Pancharatnam-Berry phase (PBP) optical element is used to manipulate the local polarization of the optical field by modulating the geometric phase. The experimental results show that this scheme can effectively create double-ring-shaped vector beams. It provides much greater flexibility to manipulate the phase and polarization by simultaneously modulating the dynamic and the geometric phases. Project supported by the National Natural Science Foundation of China (Grant No. 11547017), the Hubei Engineering University Research Foundation, China (Grant No. z2014001), and the Natural Science Foundation of Hubei Province, China (Grant No. 2014CFB578).

Acoustic bed velocity and bed load dynamics in a large sand bed river

USGS Publications Warehouse

Gaeuman, D.; Jacobson, R.B.

2006-01-01

Development of a practical technology for rapid quantification of bed load transport in large rivers would represent a revolutionary advance for sediment monitoring and the investigation of fluvial dynamics. Measurement of bed load motion with acoustic Doppler current profiles (ADCPs) has emerged as a promising approach for evaluating bed load transport. However, a better understanding of how ADCP data relate to conditions near the stream bed is necessary to make the method practical for quantitative applications. In this paper, we discuss the response of ADCP bed velocity measurements, defined as the near-bed sediment velocity detected by the instrument's bottom-tracking feature, to changing sediment-transporting conditions in the lower Missouri River. Bed velocity represents a weighted average of backscatter from moving bed load particles and spectral reflections from the immobile bed. The ratio of bed velocity to mean bed load particle velocity depends on the concentration of the particles moving in the bed load layer, the bed load layer thickness, and the backscatter strength from a unit area of moving particles relative to the echo strength from a unit area of unobstructed bed. A model based on existing bed load transport theory predicted measured bed velocities from hydraulic and grain size measurements with reasonable success. Bed velocities become more variable and increase more rapidly with shear stress when the transport stage, defined as the ratio of skin friction to the critical shear stress for particle entrainment, exceeds a threshold of about 17. This transition in bed velocity response appears to be associated with the appearance of longer, flatter bed forms at high transport stages.

New sedimentary-core records and a recent co-seismic turbidite help to unravel the paleoseismicity of the Hikurangi Subduction Zone, New Zealand

NASA Astrophysics Data System (ADS)

Barnes, Philip; Orpin, Alan; Howarth, Jamie; Patton, Jason; Lamarche, Geoffroy; Woelz, Susanne; Hopkins, Jenni; Gerring, Peter; Mitchell, John; Quinn, Will; McKeown, Monique; Ganguly, Aratrika; Banks, Simon; Davidson, Sam

2017-04-01

The Hikurangi margin straddles the convergent boundary between the Pacific and Australia tectonic plates and is New Zealand's potentially largest earthquake and tsunami hazard. The 3000 m-deep Hikurangi Trough, off eastern Marlborough, Wairarapa, Hawkes Bay, and East Cape, marks the location where the Pacific plate is subducting beneath the eastern continental margin of the North Island and northeastern South Island. To date the Hikurangi margin has a short historical record relative to the recurrence of great earthquakes and tsunami, and consequently the associated hazard remains poorly constrained. In October 2016 a new, international, 5-year project commenced to evaluate the pre-historic earthquake history of the margin. In November 2016 a RV Tangaroa voyage acquired 50 sediment cores up to 5.5 m long from sites on the continental margin between the Kaikoura coast and Poverty Bay. Core sites were selected using available 30 kHz multibeam bathymetry and backscatter data, sub-bottom acoustic profiles, archived sediment samples, and results from numerical modelling of turbidity currents. Sites fell into three general categories: turbidite distributary systems; small isolated slope-basins; and Hikurangi Channel, levees, and trough. Typical of the margin, the terrigenous-dominated sequence included layers of gravel, sand, mud, and volcanic ash. Many of these layers are turbidites, some of which may have been triggered by strong shaking associated with earthquakes (subduction megathrust and other coastal faults). Some cores contain up to 25 individual turbidites. This library of turbidites may provide the basis of new paleoseismic records that span several hundred kilometres of strike along the plate boundary. During the voyage the 14th November 2016 (NZDT) Mw 7.8 Kaikoura Earthquake occurred, causing strong ground shaking beneath the Kaikoura Canyon region. Sampling with a multicorer within five days of the earthquake, we recovered what appeared to be a very recently emplaced, still-fluidised, co-seismic turbidite about 10-20 cm thick over a very large region offshore of Marlborough and Wairarapa. This event appears to extend at least 300 km from Kaikoura and offers a rare opportunity to calibrate our paleoseismic data and to test hypotheses of turbidite triggering and emplacement. Up to five cores detected this highly fluidised layer overlying the pre-earthquake seabed, clearly visible as an oxidised layer. Our sampling spanned channel, channel-levee, and basin floor environments. On-board observations indicated that the turbidite was still settling on the seabed and the boundary with the overlying water column was diffuse. Further laboratory characterisation of the stratigraphy, physical properties, and benthic assemblages along with radionuclide analyses will test this hypothesis further.

Endotoxin, coliform, and dust levels in various types of rodent bedding.

PubMed

Whiteside, Tanya E; Thigpen, Julius E; Kissling, Grace E; Grant, Mary G; Forsythe, Diane

2010-03-01

Endotoxins in grain dust, household dust, and animal bedding may induce respiratory symptoms in rodents and humans. We assayed the endotoxin, coliform, and dust levels in 20 types of rodent bedding. Endotoxin concentrations were measured by using a commercial test kit, coliform counts were determined by using conventional microbiologic procedures, and dust content was evaluated by using a rotating-tapping shaker. Paper bedding types contained significantly less endotoxin than did other bedding types; the highest levels of endotoxin were detected in hardwood and corncob beddings. The range of endotoxin content for each bedding type was: corncob bedding, 1913 to 4504 endotoxin units per gram (EU/g); hardwood bedding, 3121 to 5401 EU/g; corncob-paper mixed bedding, 1586 to 2416 EU/g; and paper bedding, less than 5 to 105 EU/g. Coliform counts varied from less than 10 to 7591 cfu/g in corncob beddings, 90 to 4010 cfu/g in corncob-paper mixed beddings, less than 10 to 137 cfu/g in hardwood beddings, and less than 10 cfu/g in paper beddings. Average dust content was less than 0.15% in all commercial bedding types. We conclude that paper bedding is the optimal bedding type for conducting LPS inhalation studies and that rodent bedding containing high levels of endotoxin may alter the results of respiratory and immunologic studies in rodents.

Endotoxin, Coliform, and Dust Levels in Various Types of Rodent Bedding

PubMed Central

Whiteside, Tanya E; Thigpen, Julius E; Kissling, Grace E; Grant, Mary G; Forsythe, Diane B

2010-01-01

Endotoxins in grain dust, household dust, and animal bedding may induce respiratory symptoms in rodents and humans. We assayed the endotoxin, coliform, and dust levels in 20 types of rodent bedding. Endotoxin concentrations were measured by using a commercial test kit, coliform counts were determined by using conventional microbiologic procedures, and dust content was evaluated by using a rotating–tapping shaker. Paper bedding types contained significantly less endotoxin than did other bedding types; the highest levels of endotoxin were detected in hardwood and corncob beddings. The range of endotoxin content for each bedding type was: corncob bedding, 1913 to 4504 endotoxin units per gram (EU/g); hardwood bedding, 3121 to 5401 EU/g; corncob–paper mixed bedding, 1586 to 2416 EU/g; and paper bedding, less than 5 to 105 EU/g. Coliform counts varied from less than 10 to 7591 cfu/g in corncob beddings, 90 to 4010 cfu/g in corncob–paper mixed beddings, less than 10 to 137 cfu/g in hardwood beddings, and less than 10 cfu/g in paper beddings. Average dust content was less than 0.15% in all commercial bedding types. We conclude that paper bedding is the optimal bedding type for conducting LPS inhalation studies and that rodent bedding containing high levels of endotoxin may alter the results of respiratory and immunologic studies in rodents. PMID:20353693

Field observations of Flood Basalt structure: Implications for offshore interpretation and sub-volcanic investigation

NASA Astrophysics Data System (ADS)

Single, R.; Jerram, D.; Pearson, D.; Hobbs, R.

2003-04-01

Field investigations in Skye and Namibia have provided insight into structure and architecture of CFBs. The studies have been developed into lava sequence models in 3-D software GoCad. The understanding has been applied to interpretation of lavas in the Faeroe-Shetland trough. Volcanics hinder petroleum exploration in this play due to their complex internal geometries and velocity structure. Seismic resolution is poor beneath volcanics. Fieldwork has shown that lavas on Skye have developed from (olivine-phyric) compound basalts towards the base of the sequence, into more massive flows higher up the succession. Fieldwork in the Etendeka CFBs reveal a similar style of lava field development. The focus of the offshore study is through the area of the GFA-99 seismic data. Detailed 3-D interpretation over the central data area is 20x20km in dimensions. The lava sequence present may be sub-divided vertically and laterally into 4 zones between the following seismic picks: Base basalt/sub-basalt sills, top compound lava-dominated series, top Middle Series, top hyaloclastites, top massive basalt. Within the lava sequence, the surfaces have rugose topographies. Lower zone lavas are characterised by discontinuous, indistinct reflectors. These are interpreted to be sub-aerially effused basalts with compound-braided architecture. Middle Series basalts are considered to be a combination of compound lavas and more massive, tabular flows. Steeply dipping seismic reflectors also form part of the Middle Series and are interpreted as foreset-bedded hyaloclastites. The uppermost lavas have strong reflection characteristics and are laterally extensive. These are interpreted to be massive tabular lavas covering an area >8.4 x10^3 km^2. Such flows exist in upper parts of CFB sequences as evidenced from fieldwork. Complex stacking arrangements of lavas seen in the field, and the complexities observed in seismic, suggest that many factors need to be considered within CFBs for improved sub-volcanic imaging. Factors include understanding: The facies-zones present, changes in velocity structure and the geometries present within facies types. EU 5th Framework Project SIMBA is a collaborative research project combining industrial and academic partners in flood basalt research. SIMBA incorporates: TotalFinaElf GRC, ARK Geophysics, Norsk Hydro, Institut Français du Pétrole (IFP) and Universities of Durham, Cambridge, UC Dublin and Brest.

Field assessment of alternative bed-load transport estimators

USGS Publications Warehouse

Gaeuman, G.; Jacobson, R.B.

2007-01-01

Measurement of near-bed sediment velocities with acoustic Doppler current profilers (ADCPs) is an emerging approach for quantifying bed-load sediment fluxes in rivers. Previous investigations of the technique have relied on conventional physical bed-load sampling to provide reference transport information with which to validate the ADCP measurements. However, physical samples are subject to substantial errors, especially under field conditions in which surrogate methods are most needed. Comparisons between ADCP bed velocity measurements with bed-load transport rates estimated from bed-form migration rates in the lower Missouri River show a strong correlation between the two surrogate measures over a wide range of mild to moderately intense sediment transporting conditions. The correlation between the ADCP measurements and physical bed-load samples is comparatively poor, suggesting that physical bed-load sampling is ineffective for ground-truthing alternative techniques in large sand-bed rivers. Bed velocities measured in this study became more variable with increasing bed-form wavelength at higher shear stresses. Under these conditions, bed-form dimensions greatly exceed the region of the bed ensonified by the ADCP, and the magnitude of the acoustic measurements depends on instrument location with respect to bed-form crests and troughs. Alternative algorithms for estimating bed-load transport from paired longitudinal profiles of bed topography were evaluated. An algorithm based on the routing of local erosion and deposition volumes that eliminates the need to identify individual bed forms was found to give results similar to those of more conventional dune-tracking methods. This method is particularly useful in cases where complex bed-form morphology makes delineation of individual bed forms difficult. ?? 2007 ASCE.

The optimal design of the bed structure of bedstand based on ABAQUS

NASA Astrophysics Data System (ADS)

Yang, Xudong; Dong, Yu; Ge, Qingkuan; Wang, Song

2017-12-01

Hydraulic transmission bedstand is one kind of the most commonly used in engineering machinery companies, and the bed structure is the most important part. Based on the original hydraulic transmission bedstand bed structure and the CAE technology, the original bed structure is improved. The optimized bed greatly saves the material of the production bed and improves the seismic performance of the bed. In the end, the performance of the optimized bed was compared with the original bed.

Particle size variations between bed load and bed material in natural gravel bed channels

Treesearch

Thomas E. Lisle

1995-01-01

Abstract - Particle sizes of bed load and bed material that represent materials transported and stored over a period of years are used to investigate selective transport in 13 previously sampled, natural gravel bed channels. The ratio (D*) of median particle size of bed material to the transport- and frequency-weighted mean of median bed load size decreases to unity...

Marginal bed load transport in a gravel bed stream, Sagehen Creek, California

USGS Publications Warehouse

Andrews, E.D.

1994-01-01

Marginal bed load transport describes the condition when relatively few bed particles are moving at any time. Bed particles resting in the shallowest bed pockets will move when the dimensionless shear stress т* exceeds a value of about 0.020. As т* increases, the number of bed particles moving increases. Significant motion of bed particles, i.e., when a substantial fraction of the bed particles are moving, occurs when т* exceeds a value of about 0.060. Thus marginal bed load transport occurs over the domain 0.020 < т* < 0.060. Marginal bed load transport rates and associated hydraulic characteristics of Sagehen Creek, a small mountain gravel bed stream, were measured on 55 days at discharges ranging from slightly less than one half of the bank-full discharge to more than 4 times the bank-full discharge. Dimensionless shear stress varied from 0.032 to 0.042, and bed particles as large as the 80th percentile of the bed surface were transported. The relation between reference dimensionless shear stress and relative particle protrusion for Sagehen Creek was determined by varying т*ri to obtain the best fit of the Parker bed load function to the measured transport rates. During the period of record (water years 1954–1991), the mean annual quantity of bed load transported past the Sagehen Creek gage was 24.7 tons. Forty-seven percent of all bed load transported during the 38 years of record occurred in just 6 years. During 10 of the 38 years of record, essentially no bed load was transported. The median diameter of bed load was 26 mm, compared to 58 mm in the surface bed material.

A Comparison of Inpatient Adult Psychiatric Services in Italy and Canada.

PubMed

Guaiana, Giuseppe; O'Reilly, Richard; Grassi, Luigi

2018-05-03

We examine the possibility the Organisation for Economic Co-operation and Development (OECD) bed count for Italy may be an underestimation of the actual beds available. We compared bedded services for mental disorders in two regions in Italy and Canada respectively. We found out that if we consider acute psychiatric beds only, the district of Ferrara has 30 beds (8.5 per 100,000) and the Middlesex and Elgin Counties have 89 beds (16.3 beds for 100,000). However, if we include the rehabilitation beds (that are located within a hospital setting in Ontario and in a residential community setting in Ferrara), we find that the district of Ferrara has 95 beds (27.0 per 100,000) and the Middlesex and Elgin Counties have 176 beds (32.3 per 100,000). As a result, the 10/100,000 beds rate for Italy reported by the OECD is an underestimate compared to figures reported for most other countries, as the beds included are hospital beds only.

Detection of patient's bed statuses in 3D using a Microsoft Kinect.

PubMed

Li, Yun; Berkowitz, Lyle; Noskin, Gary; Mehrotra, Sanjay

2014-01-01

Patients spend the vast majority of their hospital stay in an unmonitored bed where various mobility factors can impact patient safety and quality. Specifically, bed positioning and a patient's related mobility in that bed can have a profound impact on risks such as pneumonias, blood clots, bed ulcers and falls. This issue has been exacerbated as the nurse-per-bed (NPB) ratio has decreased in recent years. To help assess these risks, it is critical to monitor a hospital bed's positional status (BPS). Two bed positional statuses, bed height (BH) and bed chair angle (BCA), are of critical interests for bed monitoring. In this paper, we develop a bed positional status detection system using a single Microsoft Kinect. Experimental results show that we are able to achieve 94.5% and 93.0% overall accuracy of the estimated BCA and BH in a simulated patient's room environment.

Modeling of Nitrogen Oxides Emissions from CFB Combustion

NASA Astrophysics Data System (ADS)

Kallio, S.; Keinonen, M.

In this work, a simplified description of combustion and nitrogen oxides chemistry was implemented in a 1.5D model framework with the aim to compare the results with ones earlier obtained with a detailed reaction scheme. The simplified chemistry was written using 12 chemical components. Heterogeneous chemistry is given by the same models as in the earlier work but the homogeneous and catalytic reactions have been altered. The models have been taken from the literature. The paper describes the numerical model with emphasis on the chemistry submodels. A simulation of combustion of bituminous coal in the Chalmers 12 MW boiler is conducted and the results are compared with the results obtained earlier with the detailed chemistry description. The results are also compared with measured O2, CO, NO and N2O profiles. The simplified reaction scheme produces equally good results as earlier obtained with the more elaborate chemistry description.

Elucidation of the biosynthesis of the methane catalyst coenzyme F430

PubMed Central

Moore, Simon J.; Sowa, Sven T.; Schuchardt, Christopher; Deery, Evelyne; Lawrence, Andrew D.; Ramos, José Vazquez; Billig, Susan; Birkemeyer, Claudia; Chivers, Peter T.; Howard, Mark J.; Rigby, Stephen E. J.; Layer, Gunhild; Warren, Martin J.

2017-01-01

Summary Methane biogenesis in methanogens is mediated by methyl-coenzyme M reductase, an enzyme that is also responsible for the utilisation of methane through anaerobic methane oxidation. The enzyme employs an ancillary factor called coenzyme F430, a nickel-containing modified tetrapyrrole that promotes catalysis through a novel methyl radical/Ni(II)-thiolate intermediate. However, the biosynthesis of coenzyme F430 from the common primogenitor uroporphyrinoge III, incorporating 11 steric centres into the macrocycle, has remained poorly understood although the pathway must involve chelation, amidation, macrocyclic ring reduction, lactamisation and carbocyclic ring formation. We have now identified the proteins that catalyse coenzyme F430 biosynthesis from sirohydrochlorin, termed CfbA-E, and shown their activity. The research completes our understanding of how nature is able to construct its repertoire of tetrapyrrole-based life pigments, permitting the development of recombinant systems to utilise these metalloprosthetic groups more widely. PMID:28225763

Rich bacterial assemblages from Maritime Antarctica (Potter Cove, South Shetlands) reveal several kinds of endemic and undescribed phylotypes.

PubMed

Landone Vescovo, Ignacio A; Golemba, Marcelo D; Di Lello, Federico A; Culasso, Andrés C A; Levin, Gustavo; Ruberto, Lucas; Mac Cormack, Walter P; López, José L

2014-01-01

Bacterial richness in maritime Antarctica has been poorly described to date. Phylogenetic affiliation of seawater free-living microbial assemblages was studied from three locations near the Argentinean Jubany Station during two Antarctic summers. Sixty 16S RNA cloned sequences were phylogenetically affiliated to Alphaproteobacteria (30/60 clones), Gammaproteobacteria(19/60 clones), Betaproteobacteria and Cytophaga-Flavobacteriia-Bacteroides (CFB), which were (2/60) and (3/60) respectively. Furthermore, six out of 60 clones could not be classified. Both, Alphaproteobacteria and Gammaproteobacteria, showed several endemic and previously undescribed sequences. Moreover, the absence of Cyanobacteria sequences in our samples is remarkable. In conclusion, we are reporting a rich sequence assemblage composed of widely divergent isolates among themselves and distant from the most closely related sequences currently deposited in data banks. Copyright © 2014 Asociación Argentina de Microbiología. Publicado por Elsevier España. All rights reserved.

Utility of Recycled Bedding for Laboratory Rodents

PubMed Central

Miyamoto, Toru; Li, Zhixia; Kibushi, Tomomi; Okano, Shinya; Yamasaki, Nakamichi; Kasai, Noriyuki

2009-01-01

Animal facilities generate a large amount of used bedding containing excrement as medical waste. We developed a recycling system for used bedding that involves soft hydrothermal processing. In this study, we examined the effects of bedding type on growth, hematologic and serum biochemical values, and organ weights of female and male mice reared on either recycled or fresh bedding from 3 to 33 wk of age. Neither growth nor physiology differed between mice housed on recycled bedding compared with fresh bedding. When 14-wk-old mice were bred, litter size and total number of weaned pups showed no significant differences between animals raised on recycled or fresh bedding. Because bedding type influences the environment within cages and animal rooms, we evaluated particulate and ammonia data from cages and animal rooms. Values were significantly lower from cages and rooms that used recycled bedding than from those using fresh bedding, thus indicating that recycled bedding has the potential to improve the environment within both cages and animal rooms. Overall, this study revealed that recycled bedding is an excellent material for use in housing laboratory rodents. Specifically, recycled bedding may reduce medical waste and maintain healthy environments within cages and animal rooms. PMID:19653951

A general power equation for predicting bed load transport rates in gravel bed rivers

Treesearch

Jeffrey J. Barry; John M. Buffington; John G. King

2004-01-01

A variety of formulae has been developed to predict bed load transport in gravel bed rivers, ranging from simple regressions to complex multiparameter formulations. The ability to test these formulae across numerous field sites has, until recently, been hampered by a paucity of bed load transport data for gravel bed rivers. We use 2104 bed load transport observations...

Method and apparatus for enhancing the desulfurization of hot coal gas in a fluid-bed coal gasifier

DOEpatents

Grindley, T.

1988-04-05

A process and apparatus for providing additional desulfurization of the hot gas produced in a fluid-bed coal gasifier, within the gasifier is described. A fluid-bed of iron oxide is located inside the gasifier above the gasification bed in a fluid-bed coal gasifier in which in-bed desulfurization by lime/limestone takes place. The product gases leave the gasification bed typically at 1600 to 1800 F and are partially quenched with water to 1000 to 1200 F before entering the iron oxide bed. The iron oxide bed provides additional desulfurization beyond that provided by the lime /limestone. 1 fig.

Method for enhancing the desulfurization of hot coal gas in a fluid-bed coal gasifier

DOEpatents

Grindley, Thomas

1989-01-01

A process and apparatus for providing additional desulfurization of the hot gas produced in a fluid-bed coal gasifier, within the gasifier. A fluid-bed of iron oxide is located inside the gasifier above the gasification bed in a fluid-bed coal gasifier in which in-bed desulfurization by lime/limestone takes place. The product gases leave the gasification bed typically at 1600.degree. to 1800.degree. F. and are partially quenched with water to 1000.degree. to 1200.degree. F. before entering the iron oxide bed. The iron oxide bed provides additional desulfurization beyond that provided by the lime/limestone.

DNA profiling of trace DNA recovered from bedding.

PubMed

Petricevic, Susan F; Bright, Jo-Anne; Cockerton, Sarah L

2006-05-25

Trace DNA is often detected on handled items and worn clothing examined in forensic laboratories. In this study, the potential transfer of trace DNA to bedding by normal contact, when an individual sleeps in a bed, is examined. Volunteers slept one night on a new, lower bed sheet in their own bed and one night in a bed foreign to them. Samples from the sheets were collected and analysed by DNA profiling. The results indicate that the DNA profile of an individual can be obtained from bedding after one night of sleeping in a bed. The DNA profile of the owner of the bed could also be detected in the foreign bed experiments. Since mixed DNA profiles can be obtained from trace DNA on bedding, caution should be exercised when drawing conclusions from DNA profiling results obtained from such samples. This transfer may have important repercussions in sexual assault investigations.

Rapid ignition of fluidized bed boiler

DOEpatents

Osborn, Liman D.

1976-12-14

A fluidized bed boiler is started up by directing into the static bed of inert and carbonaceous granules a downwardly angled burner so that the hot gases cause spouting. Air is introduced into the bed at a rate insufficient to fluidize the entire bed. Three regions are now formed in the bed, a region of lowest gas resistance, a fluidized region and a static region with a mobile region at the interface of the fluidized and static regions. Particles are transferred by the spouting action to form a conical heap with the carbonaceous granules concentrated at the top. The hot burner gases ignite the carbonaceous matter on the top of the bed which becomes distributed in the bed by the spouting action and bed movement. Thereafter the rate of air introduction is increased to fluidize the entire bed, the spouter/burner is shut off, and the entire fluidized bed is ignited.

AIR PASSIVATION OF METAL HYDRIDE BEDS FOR WASTE DISPOSAL

DOE Office of Scientific and Technical Information (OSTI.GOV)

Klein, J; R. H. Hsu, R

2007-07-02

Metal hydride beds offer compact, safe storage of tritium. After metal hydride beds have reached the end of their useful life, the beds will replaced with new beds and the old beds prepared for disposal. One acceptance criteria for hydride bed waste disposal is that the material inside the bed not be pyrophoric. To determine the pyrophoric nature of spent metal hydride beds, controlled air ingress tests were performed. A simple gas handling manifold fitted with pressure transducers and a calibrated volume were used to introduce controlled quantities of air into a metal hydride bed and the bed temperature risemore » monitored for reactivity with the air. A desorbed, 4.4 kg titanium prototype hydride storage vessel (HSV) produced a 4.4 C internal temperature rise upon the first air exposure cycle and a 0.1 C temperature rise upon a second air exposure. A total of 346 scc air was consumed by the bed (0.08 scc per gram Ti). A desorbed, 9.66 kg LaNi{sub 4.25}Al{sub 0.75} prototype storage bed experienced larger temperature rises over successive cycles of air ingress and evacuation. The cycles were performed over a period of days with the bed effectively passivated after the 12th cycle. Nine to ten STP-L of air reacted with the bed producing both oxidized metal and water.« less

7 CFR 3201.15 - Bedding, bed linens, and towels.

Code of Federal Regulations, 2014 CFR

2014-01-01

... group of woven cloth products used as coverings on a bed. Bedding includes products such as blankets, bedspreads, comforters, and quilts. (2) Bed linens are woven cloth sheets and pillowcases used in bedding. (3) Towels are woven cloth products used primarily for drying and wiping. (b) Minimum biobased content. The...

7 CFR 2902.15 - Bedding, bed linens, and towels.

Code of Federal Regulations, 2011 CFR

2011-01-01

... group of woven cloth products used as coverings on a bed. Bedding includes products such as blankets, bedspreads, comforters, and quilts. (2) Bed linens are woven cloth sheets and pillowcases used in bedding. (3) Towels are woven cloth products used primarily for drying and wiping. (b) Minimum biobased content. The...

7 CFR 3201.15 - Bedding, bed linens, and towels.

Code of Federal Regulations, 2012 CFR

2012-01-01

... group of woven cloth products used as coverings on a bed. Bedding includes products such as blankets, bedspreads, comforters, and quilts. (2) Bed linens are woven cloth sheets and pillowcases used in bedding. (3) Towels are woven cloth products used primarily for drying and wiping. (b) Minimum biobased content. The...

7 CFR 3201.15 - Bedding, bed linens, and towels.

Code of Federal Regulations, 2013 CFR

2013-01-01

... group of woven cloth products used as coverings on a bed. Bedding includes products such as blankets, bedspreads, comforters, and quilts. (2) Bed linens are woven cloth sheets and pillowcases used in bedding. (3) Towels are woven cloth products used primarily for drying and wiping. (b) Minimum biobased content. The...

The underlying reasons for very high levels of bed net use, and higher malaria infection prevalence among bed net users than non-users in the Tanzanian city of Dar es Salaam: a qualitative study.

PubMed

Msellemu, Daniel; Shemdoe, Aloysia; Makungu, Christina; Mlacha, Yeromini; Kannady, Khadija; Dongus, Stefan; Killeen, Gerry F; Dillip, Angel

2017-10-23

Bed nets reduce malaria-related illness and deaths, by forming a protective barrier around people sleeping under them. When impregnated with long-lasting insecticide formulations they also repel or kill mosquitoes attempting to feed upon sleeping humans, and can even suppress entire populations of malaria vectors that feed predominantly upon humans. Nevertheless, an epidemiological study in 2012 demonstrated higher malaria prevalence among bed net users than non-users in urban Dar es Salaam, Tanzania. Focus group discussions were conducted with women from four selected wards of Dar es Salaam city, focusing on four major themes relating to bed net use behaviours: (1) reasons for bed net use, (2) reasons for not using bed nets, (3) stimuli or reminders for people to use a bed net (4) perceived reasons for catching malaria while using a bed net. An analytical method by framework grouping of relevant themes was used address key issues of relevance to the study objectives. Codes were reviewed and grouped into categories and themes. All groups said the main reason for bed net use was protection against malaria. Houses with well-screened windows, with doors that shut properly, and that use insecticidal sprays against mosquitoes, were said not to use bed nets, while frequent attacks from malaria was the main stimulus for people to use bed nets. Various reasons were mentioned as potential reasons that compromise bed net efficacy, the most common of which were: (1) bed net sharing by two or more people, especially if one occupant tends to come to bed late at night, and does not tuck in the net 71%; (2) one person shares the bed but does not use the net, moving it away from the side on which s/he sleeps 68%; (3) ineffective usage habits, called ulalavi, in which a sprawling sleeper either touches the net while sleeping up against it or leaves a limb hanging outside of it 68%. Less common reasons mentioned included: (1) Small bed nets which become un-tucked at night (31%); (2) Bed nets with holes large enough to allow mosquitoes to pass (28%); and (3) Going to bed late after already being bitten outdoors (24%). Behaviours associated with bed net use like; bed sharing, bed net non compliant-bedfellow, sleeping pattern like ulalavi and some physical bed net attributes compromise its effectiveness and supposedly increase of malaria infection to bed net users. While some well-screened houses looked to instigate low malaria prevalence to non-bed net users.

Odorous Volatile Organic Compounds, Escherichia coli, and Nutrient Concentrations when Kiln-Dried Pine Chips and Corn Stover Bedding Are Used in Beef Bedded Manure Packs.

PubMed

Spiehs, Mindy J; Berry, Elaine D; Wells, James E; Parker, David B; Brown-Brandl, Tami M

2017-07-01

Pine ( spp.) bedding has been shown to lower the concentration of odorous volatile organic compounds (VOCs) and pathogenic bacteria compared with corn ( L.) stover bedding, but availability and cost limit the use of pine bedding in cattle confinement facilities. The objectives of this study were to determine if the addition of pine wood chips to laboratory-scaled bedded packs containing corn stover (i) reduced odorous VOC emissions; (ii) reduced total ; and (iii) changed the nutrient composition of the resulting manure-bedded packs. Bedding treatments included 0, 10, 20, 30, 40, 60, 80, and 100% pine chips, with the balance being corn stover. Four bedded packs for each mixture were maintained for 42 d ( = 4 observations per bedding material). The production of total sulfur compounds increased significantly when 100% pine chips were used (44.72 ng L) compared with bedding mixture containing corn stover (18.0-24.56 ng L). The carbon-to-nitrogen ratio exceeded the ideal ratio of 24:1 for the optimum activity of soil microorganisms when ≥60% pine chips (25.3-27.5 ng L) were included in the mixture. The use of 100% pine chips as bedding increased sulfide concentration in the facility 1.8 to 2.4 times over the use of corn stover bedding. was not influenced by the addition of pine chips to the corn stover bedding material but did decrease as the bedded pack aged. Bedding material mixtures containing 30 to 60% pine and 40 to 70% corn stover may be the ideal combination to mitigate odors from livestock facilities using deep bedded systems. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Development of the 7-Item Binge-Eating Disorder Screener (BEDS-7)

PubMed Central

Deal, Linda S.; DiBenedetti, Dana B.; Nelson, Lauren; Fehnel, Sheri E.; Brown, T. Michelle

2016-01-01

Objective Develop a brief, patient-reported screening tool designed to identify individuals with probable binge-eating disorder (BED) for further evaluation or referral to specialists. Methods Items were developed on the basis of the DSM-5 diagnostic criteria, existing tools, and input from 3 clinical experts (January 2014). Items were then refined in cognitive debriefing interviews with participants self-reporting BED characteristics (March 2014) and piloted in a multisite, cross-sectional, prospective, noninterventional study consisting of a semistructured diagnostic interview (to diagnose BED) and administration of the pilot Binge-Eating Disorder Screener (BEDS), Binge Eating Scale (BES), and RAND 36-Item Short-Form Health Survey (RAND-36) (June 2014–July 2014). The sensitivity and specificity of classification algorithms (formed from the pilot BEDS item-level responses) in predicting BED diagnosis were evaluated. The final algorithm was selected to minimize false negatives and false positives, while utilizing the fewest number of BEDS items. Results Starting with the initial BEDS item pool (20 items), the 13-item pilot BEDS resulted from the cognitive debriefing interviews (n = 13). Of the 97 participants in the noninterventional study, 16 were diagnosed with BED (10/62 female, 16%; 6/35 male, 17%). Seven BEDS items (BEDS-7) yielded 100% sensitivity and 38.7% specificity. Participants correctly identified (true positives) had poorer BES scores and RAND-36 scores than participants identified as true negatives. Conclusions Implementation of the brief, patient-reported BEDS-7 in real-world clinical practice is expected to promote better understanding of BED characteristics and help physicians identify patients who may have BED. PMID:27486542

Development of the 7-Item Binge-Eating Disorder Screener (BEDS-7).

PubMed

Herman, Barry K; Deal, Linda S; DiBenedetti, Dana B; Nelson, Lauren; Fehnel, Sheri E; Brown, T Michelle

2016-01-01

Develop a brief, patient-reported screening tool designed to identify individuals with probable binge-eating disorder (BED) for further evaluation or referral to specialists. Items were developed on the basis of the DSM-5 diagnostic criteria, existing tools, and input from 3 clinical experts (January 2014). Items were then refined in cognitive debriefing interviews with participants self-reporting BED characteristics (March 2014) and piloted in a multisite, cross-sectional, prospective, noninterventional study consisting of a semistructured diagnostic interview (to diagnose BED) and administration of the pilot Binge-Eating Disorder Screener (BEDS), Binge Eating Scale (BES), and RAND 36-Item Short-Form Health Survey (RAND-36) (June 2014-July 2014). The sensitivity and specificity of classification algorithms (formed from the pilot BEDS item-level responses) in predicting BED diagnosis were evaluated. The final algorithm was selected to minimize false negatives and false positives, while utilizing the fewest number of BEDS items. Starting with the initial BEDS item pool (20 items), the 13-item pilot BEDS resulted from the cognitive debriefing interviews (n = 13). Of the 97 participants in the noninterventional study, 16 were diagnosed with BED (10/62 female, 16%; 6/35 male, 17%). Seven BEDS items (BEDS-7) yielded 100% sensitivity and 38.7% specificity. Participants correctly identified (true positives) had poorer BES scores and RAND-36 scores than participants identified as true negatives. Implementation of the brief, patient-reported BEDS-7 in real-world clinical practice is expected to promote better understanding of BED characteristics and help physicians identify patients who may have BED.

Deposition of Suspended Clay to Open and Sand-Filled Framework Gravel Beds in a Laboratory Flume

NASA Astrophysics Data System (ADS)

Mooneyham, Christian; Strom, Kyle

2018-01-01

Pulses of fine sediment composed of sand, silt, and clay can be introduced to gravel bed rivers through runoff from burn-impacted hillslopes, landslides, bank failure, or the introduction of reservoir sediment as a result of sluicing or dam decommissioning. Here we present a study aimed at quantifying exchange between suspensions of clay and gravel beds. The questions that motivate the work are: how do bed roughness and pore space characteristics, shear velocity (u∗), and initial concentration (C0) affect clay deposition on or within gravel beds? Where does deposition within these beds occur, and can deposited clay be resuspended while the gravel is immobile? We examine these questions in a laboratory flume using acrylic, open-framework gravel, and armored sand-gravel beds under conditions of varying u∗ and C0. Deposition of clay occurred to all beds (even with Rouse numbers ˜ 0.01). We attribute deposition under full suspension conditions to be an outcome of localized protected zones where clay can settle and available pore space in the bed. For smooth wall cases, protection came from the viscous wall region and the development of bed forms; for the rough beds, protection came from separation zones and low-velocity pore spaces. Bed porosity was the strongest influencer of nondimensional deposition rate; deposition increased with porosity. Deposition was inversely related to u∗ for the acrylic bed runs; no influence of u∗ was found for the porous bed runs. Increases in discharge resulted in resuspension of clay from acrylic beds; no resuspension was observed in the porous bed runs.

Bacillus cereus in free-stall bedding.

PubMed

Magnusson, M; Svensson, B; Kolstrup, C; Christiansson, A

2007-12-01

To increase the understanding of how different factors affect the bacterial growth in deep sawdust beds for dairy cattle, the microbiological status of Bacillus cereus and coliforms in deep sawdust-bedded free stalls was investigated over two 14-d periods on one farm. High counts of B. cereus and coliforms were found in the entire beds. On average, 4.1 log(10) B. cereus spores, 5.5 log(10) B. cereus, and 6.7 log(10) coliforms per gram of bedding could be found in the upper layers of the sawdust likely to be in contact with the cows' udders. The highest counts of B. cereus spores, B. cereus, and coliforms were found in the bedding before fresh bedding was added, and the lowest immediately afterwards. Different factors of importance for the growth of B. cereus in the bedding material were explored in laboratory tests. These were found to be the type of bedding, pH, and the type and availability of nutrients. Alternative bedding material such as peat and mixtures of peat and sawdust inhibited the bacterial growth of B. cereus. The extent of growth of B. cereus in the sawdust was increased in a dose-dependent manner by the availability of feces. Urine added to different bedding material raised the pH and also led to bacterial growth of B. cereus in the peat. In sawdust, a dry matter content greater than 70% was needed to lower the water activity to 0.95, which is needed to inhibit the growth of B. cereus. In an attempt to reduce the bacterial growth of B. cereus and coliforms in deep sawdust beds on the farm, the effect of giving bedding daily or a full replacement of the beds was studied. The spore count of B. cereus in the back part of the free stalls before fresh bedding was added was 0.9 log units lower in stalls given daily bedding than in stalls given bedding twice weekly. No effect on coliform counts was found. Replacement of the entire sawdust bedding had an effect for a short period, but by 1 to 2 mo after replacement, the counts of B. cereus spores in the beds had increased about 2 log units and were as high as they were before bed replacement. Therefore, free-stall management could, to a limited extent, reduce the content of B. cereus spores in the beds by daily bedding and entire bed replacement.

Bed Bugs FAQs

MedlinePlus

... Consultations, and General Public. Contact Us Parasites Home Bed Bugs FAQs Recommend on Facebook Tweet Share Compartir On ... are bed bugs treated and prevented? What are bed bugs? Bed bugs ( Cimex lectularius ) are small, flat, parasitic ...

Staged fluidized-bed combustion and filter system

DOEpatents

Mei, Joseph S.; Halow, John S.

1994-01-01

A staged fluidized-bed combustion and filter system for substantially reducing the quantity of waste through the complete combustion into ash-type solids and gaseous products. The device has two fluidized-bed portions, the first primarily as a combustor/pyrolyzer bed, and the second as a combustor/filter bed. The two portions each have internal baffles to define stages so that material moving therein as fluidized beds travel in an extended route through those stages. Fluidization and movement is achieved by the introduction of gases into each stage through a directional nozzle. Gases produced in the combustor/pyrolyzer bed are permitted to travel into corresponding stages of the combustor/filter bed through screen filters that permit gas flow but inhibit solids flow. Any catalyst used in the combustor/filter bed is recycled. The two beds share a common wall to minimize total volume of the system. A slightly modified embodiment can be used for hot gas desulfurization and sorbent regeneration. Either side-by-side rectangular beds or concentric beds can be used. The system is particularly suited to the processing of radioactive and chemically hazardous waste.

EPA-Registered Bed Bug Products

MedlinePlus

... Bugs EPA Registered Bed Bug Products EPA-Registered Bed Bug Products Resources Bed Bug Main Page Top Ten ... Where you can use the pesticide Pesticide type Bed Bug Search Tool Enter the information as described in ...

Health Information in Oromo (Afan Oromoo)

MedlinePlus

... Section Bed Bugs Bed Bug Control in Residences - English PDF Bed Bug Control in Residences - Afan Oromoo ( ... Department of Agriculture Vacuuming to Capture Bed Bugs - English PDF Vacuuming to Capture Bed Bugs - Afan Oromoo ( ...

General and food-specific inhibitory deficits in binge eating disorder.

PubMed

Svaldi, Jennifer; Naumann, Eva; Trentowska, Monika; Schmitz, Florian

2014-07-01

To investigate behavioral inhibition in individuals with binge eating disorder (BED) compared with overweight and obese individuals without BED (No-BED). Participants with BED (n = 31) and the weight-matched No-BED group (n = 29) completed an inhibitory control task (stop-signal task, SST) with food and neutral stimuli. The BED group needed more time to stop an ongoing response, as indicated by increased stop signal reaction time (SSRT) relative to the No-BED group. Additionally, compared with the No-BED group, the BED group displayed more difficulty inhibiting responses elicited by food stimuli. The deficits in behavioral response inhibition were also found to be related to the severity of reported symptoms. There is a general deficit in late stage behavioral inhibition in BED, and this may be particularly pronounced in the context of food stimuli. © 2014 Wiley Periodicals, Inc.

Thermal enhancement cartridge heater modified (TECH Mod) tritium hydride bed development, Part 1 - Design and fabrication

DOE Office of Scientific and Technical Information (OSTI.GOV)

Klein, J.E.; Estochen, E.G.

The Savannah River Site (SRS) tritium facilities have used first generation (Gen1) LaNi{sub 4.25}Al{sub 0.75} (LANA0.75) metal hydride storage beds for tritium absorption, storage, and desorption. The Gen1 design utilizes hot and cold nitrogen supplies to thermally cycle these beds. Second and third generation (Gen2 and Gen3) storage bed designs include heat conducting foam and divider plates to spatially fix the hydride within the bed. For thermal cycling, the Gen2 and Gen3 beds utilize internal electric heaters and glovebox atmosphere flow over the bed inside the bed external jacket for cooling. The currently installed Gen1 beds require replacement due tomore » tritium aging effects on the LANA0.75 material, and cannot be replaced with Gen2 or Gen3 beds due to different designs of these beds. At the end of service life, Gen1 bed desorption efficiencies are limited by the upper temperature of hot nitrogen supply. To increase end-of-life desorption efficiency, the Gen1 bed design was modified, and a Thermal Enhancement Cartridge Heater Modified (TECH Mod) bed was developed. Internal electric cartridge heaters in the new design to improve end-of-life desorption, and also permit in-bed tritium accountability (IBA) calibration measurements to be made without the use of process tritium. Additional enhancements implemented into the TECH Mod design are also discussed. (authors)« less

THERMAL ENHANCEMENT CARTRIDGE HEATER MODIFIED TECH MOD TRITIUM HYDRIDE BED DEVELOPMENT PART I DESIGN AND FABRICATION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Klein, J.; Estochen, E.

The Savannah River Site (SRS) tritium facilities have used 1{sup st} generation (Gen1) LaNi{sub 4.25}Al{sub 0.75} (LANA0.75) metal hydride storage beds for tritium absorption, storage, and desorption. The Gen1 design utilizes hot and cold nitrogen supplies to thermally cycle these beds. Second and 3{sup rd} generation (Gen2 and Gen3) storage bed designs include heat conducting foam and divider plates to spatially fix the hydride within the bed. For thermal cycling, the Gen2 and Gen 3 beds utilize internal electric heaters and glovebox atmosphere flow over the bed inside the bed external jacket for cooling. The currently installed Gen1 beds requiremore » replacement due to tritium aging effects on the LANA0.75 material, and cannot be replaced with Gen2 or Gen3 beds due to different designs of these beds. At the end of service life, Gen1 bed desorption efficiencies are limited by the upper temperature of hot nitrogen supply. To increase end-of-life desorption efficiency, the Gen1 bed design was modified, and a Thermal Enhancement Cartridge Heater Modified (TECH Mod) bed was developed. Internal electric cartridge heaters in the new design to improve end-of-life desorption, and also permit in-bed tritium accountability (IBA) calibration measurements to be made without the use of process tritium. Additional enhancements implemented into the TECH Mod design are also discussed.« less

Petrology and geochemistry of samples from bed-contact zones in Tunnel Bed 5, U12g-Tunnel, Nevada Test Site

DOE Office of Scientific and Technical Information (OSTI.GOV)

Connolly, J.R.; Keil, K.; Mansker, W.L.

1984-10-01

This report summarizes the detailed geologic characterization of samples of bed-contact zones and surrounding nonwelded bedded tuffs, both within Tunnel Bed 5, that are exposed in the G-Tunnel complex beneath Rainier Mesa on the Nevada Test Site (NTS). Original planning studies treated the bed-contact zones in Tunnel Bed 5 as simple planar surfaces of relatively high permeability. Detailed characterization, however, indicates that these zones have a finite thickness, are depositional in origin, vary considerably over short vertical and horizontal distances, and are internally complex. Fluid flow in a sequence of nonwelded zeolitized ash-flow or bedded tuffs and thin intervening reworkedmore » zones appears to be a porous-medium phenomenon, regardless of the presence of layering. There are no consistent differences in either bulk composition or detailed mineralogy between bedded tuffs and bed-contact zones in Tunnel Bed 5. Although the original bulk composition of Tunnel Bed 5 was probably peralkaline, extensive zeolitization has resulted in a present peraluminous bulk composition of both bedded tuffs and bed-contact zones. The major zeolite present, clinoptilolite, is intermediate (Ca:K:Na = 26:35:39) and effectively uniform in composition. This composition is similar to that of clinoptilolite from the tuffaceous beds of Calico Hills above the static water level in hole USW G-1, but somewhat different from that reported for zeolites from below the static water level in USW G-2. Tunnel Bed 5 also contains abundant hydrous manganese oxides. The similarity in composition of the clinoptilolites from Tunnel Bed 5 and those above the static water level at Yucca Mountain indicates that many of the results of nuclide-migration experiments in Tunnel Bed 5 would be transferrable to zeolitized nonwelded tuffs above the static water level at Yucca Mountain.« less

Prediction model for prevalence and incidence of advanced age-related macular degeneration based on genetic, demographic, and environmental variables.

PubMed

Seddon, Johanna M; Reynolds, Robyn; Maller, Julian; Fagerness, Jesen A; Daly, Mark J; Rosner, Bernard

2009-05-01

The joint effects of genetic, ocular, and environmental variables were evaluated and predictive models for prevalence and incidence of AMD were assessed. Participants in the multicenter Age-Related Eye Disease Study (AREDS) were included in a prospective evaluation of 1446 individuals, of which 279 progressed to advanced AMD (geographic atrophy or neovascular disease) and 1167 did not progress during 6.3 years of follow-up. For prevalent AMD, 509 advanced cases were compared with 222 controls. Covariates for the incidence analysis included age, sex, education, smoking, body mass index (BMI), baseline AMD grade, and the AREDS vitamin-mineral treatment assignment. DNA specimens were evaluated for six variants in five genes related to AMD. Unconditional logistic regression analyses were performed for prevalent and incident advanced AMD. An algorithm was developed and receiver operating characteristic curves and C statistics were calculated to assess the predictive ability of risk scores to discriminate progressors from nonprogressors. All genetic polymorphisms were independently related to prevalence of advanced AMD, controlling for genetic factors, smoking, BMI, and AREDS treatment. Multivariate odds ratios (ORs) were 3.5 (95% confidence interval [CI], 1.7-7.1) for CFH Y402H; 3.7 (95% CI, 1.6-8.4) for CFH rs1410996; 25.4 (95% CI, 8.6-75.1) for LOC387715 A69S (ARMS2); 0.3 (95% CI, 0.1-0.7) for C2 E318D; 0.3 (95% CI, 0.1-0.5) for CFB; and 3.6 (95% CI, 1.4-9.4) for C3 R102G, comparing the homozygous risk/protective genotypes to the referent genotypes. For incident AMD, all these variants except CFB were significantly related to progression to advanced AMD, after controlling for baseline AMD grade and other factors, with ORs from 1.8 to 4.0 for presence of two risk alleles and 0.4 for the protective allele. An interaction was seen between CFH402H and treatment, after controlling for all genotypes. Smoking was independently related to AMD, with a multiplicative joint effect with genotype on AMD risk. The C statistic for the full model with all variables was 0.831 for progression to advanced AMD. Factors reflective of nature and nurture are independently related to prevalence and incidence of advanced AMD, with excellent predictive power.

The initiation and evolution of the River Nile

NASA Astrophysics Data System (ADS)

Fielding, Laura; Najman, Yani; Millar, Ian; Butterworth, Peter; Garzanti, Eduardo; Vezzoli, Giovanni; Barfod, Dan; Kneller, Ben

2018-05-01

The Nile is generally regarded as the longest river in the world. Knowledge of the timing of the Nile's initiation as a major river is important to a number of research questions. For example, the timing of the river's establishment as a catchment of continental proportions can be used to document surface uplift of its Ethiopian upland drainage, with implications for constraining rift tectonics. Furthermore, the time of major freshwater input to the Mediterranean is considered to be an important factor in the development of sapropels. Yet the river's initiation as a major drainage is currently constrained no more precisely than Eocene to Pleistocene. Within the modern Nile catchment, voluminous Cenozoic Continental Flood Basalts (CFBs) are unique to the Ethiopian Highlands; thus first detection of their presence in the Nile delta record indicates establishment of the river's drainage at continental proportions at that time. We present the first detailed multiproxy provenance study of Oligocene-Recent Nile delta cone sediments. We demonstrate the presence of Ethiopian CFB detritus in the Nile delta from the start of our studied record (c. 31 Ma) by (1) documenting the presence of zircons with U-Pb ages unique, within the Nile catchment, to the Ethiopian CFBs and (2) using Sr-Nd data to construct a mixing model which indicates a contribution from the CFBs. We thereby show that the Nile river was established as a river of continental proportions by Oligocene times. We use petrography and heavy mineral data to show that previous petrographic provenance studies which proposed a Pleistocene age for first arrival of Ethiopian CFBs in the Nile delta did not take into account the strong diagenetic influence on the samples. We use a range of techniques to show that sediments were derived from Phanerozoic sedimentary rocks that blanket North Africa, Arabian-Nubian Shield basement terranes, and Ethiopian CFB's. We see no significant input from Archaean cratons supplied directly via the White Nile in any of our samples. Whilst there are subtle differences between our Nile delta samples from the Oligocene and Pliocene compared to those from the Miocene and Pleistocene, the overall stability of our signal throughout the delta record, and its similarity to the modern Nile signature, indicates no major change in the Nile's drainage from Oligocene to present day.

CFD-DEM study of effect of bed thickness for bubbling fluidized beds

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tingwen, Li; Gopalakrishnan, Pradeep; Garg, Rahul

2011-10-01

The effect of bed thickness in rectangular fluidized beds is investigated through the CFD–DEM simulations of small-scale systems. Numerical results are compared for bubbling fluidized beds of various bed thicknesses with respect to particle packing, bed expansion, bubble behavior, solids velocities, and particle kinetic energy. Good two-dimensional (2D) flow behavior is observed in the bed having a thickness of up to 20 particle diameters. However, a strong three-dimensional (3D) flow behavior is observed in beds with a thickness of 40 particle diameters, indicating the transition from 2D flow to 3D flow within the range of 20–40 particle diameters. Comparison ofmore » velocity profiles near the walls and at the center of the bed shows significant impact of the front and back walls on the flow hydrodynamics of pseudo-2D fluidized beds. Hence, for quantitative comparison with experiments in pseudo-2D columns, the effect of walls has to be accounted for in numerical simulations.« less

Method and apparatus for a combination moving bed thermal treatment reactor and moving bed filter

DOEpatents

Badger, Phillip C.; Dunn, Jr., Kenneth J.

2015-09-01

A moving bed gasification/thermal treatment reactor includes a geometry in which moving bed reactor particles serve as both a moving bed filter and a heat carrier to provide thermal energy for thermal treatment reactions, such that the moving bed filter and the heat carrier are one and the same to remove solid particulates or droplets generated by thermal treatment processes or injected into the moving bed filter from other sources.

Control of bed height in a fluidized bed gasification system

DOEpatents

Mehta, Gautam I.; Rogers, Lynn M.

1983-12-20

In a fluidized bed apparatus a method for controlling the height of the fdized bed, taking into account variations in the density of the bed. The method comprises taking simultaneous differential pressure measurements at different vertical elevations within the vessel, averaging the differential pressures, determining an average fluidized bed density, then periodically calculating a weighting factor. The weighting factor is used in the determination of the actual bed height which is used in controlling the fluidizing means.

Aerodynamics and deposition effects of inhaled submicron drug aerosol in airway diseases.

PubMed

Faiyazuddin, Md; Mujahid, Md; Hussain, Talib; Siddiqui, Hefazat H; Bhatnagar, Aseem; Khar, Roop K; Ahmad, Farhan J

2013-01-01

Particle engineering is the prime focus to improve pulmonary drug targeting with the splendor of nanomedicines. In recent years, submicron particles have emerged as prettyful candidate for improved fludisation and deposition. For effective deposition, the particle size must be in the range of 0.5-5 μm. Inhalers design for the purpose of efficient delivery of powders to lungs is again a crucial task for pulmonary scientists. A huge number of DPI devices exist in the market, a significant number are awaiting FDA approval, some are under development and a large number have been patented or applied for patent. Even with superior design, the delivery competence is still deprived, mostly due to fluidisation problems which cause poor aerosol generation and deposition. Because of the cohesive nature and poor flow characteristics, they are difficult to redisperse upon aerosolization with breath. These problems are illustrious in aerosol research, much of which is vastly pertinent to pulmonary therapeutics. A technical review is presented here of advances that have been utilized in production of submicron drug particles, their in vitro/in vivo evaluations, aerosol effects and pulmonary fate of inhaled submicron powders.

Evaluation of a clay-based acidic bedding conditioner for dairy cattle bedding.

PubMed

Proietto, R L; Hinckley, L S; Fox, L K; Andrew, S M

2013-02-01

This study investigated the effects of a clay-based acidic bedding conditioner on sawdust bedding pH, dry matter (DM), environmental pathogen counts, and environmental bacterial counts on teat ends of lactating dairy cows. Sixteen lactating Holstein cows were paired based on parity, days in milk, milk yield, and milk somatic cell count, and were negative for the presence of an intramammary pathogen. Within each pair, cows were randomly assigned to 1 of 2 treatments with 3-wk periods in a crossover design. Treatment groups consisted of 9 freestalls per group bedded with either untreated sawdust or sawdust with a clay-based acidic bedding conditioner, added at 3- to 4-d intervals over each 21-d period. Bedding and teat ends were aseptically sampled on d 0, 1, 2, 7, 14, and 21 for determination of environmental bacterial counts. At the same time points, bedding was sampled for DM and pH determination. The bacteria identified in the bedding material were total gram-negative bacteria, Streptococcus spp., and coliform bacteria. The bacteria identified on the teat ends were Streptococcus spp., coliform bacteria, and Klebsiella spp. Teat end score, milk somatic cell count, and intramammary pathogen presence were measured weekly. Bedding and teat cleanliness, environmental high and low temperatures, and dew point data were collected daily. The bedding conditioner reduced the pH, but not the DM, of the sawdust bedding compared with untreated sawdust. Overall environmental bacterial counts in bedding were lower for treated sawdust. Total bacterial counts in bedding and on teat ends increased with time over both periods. Compared with untreated sawdust, the treated bedding had lower counts of total gram-negative bacteria and streptococci, but not coliform counts. Teat end bacterial counts were lower for cows bedded on treated sawdust for streptococci, coliforms, and Klebsiella spp. compared with cows bedded on untreated sawdust. The clay-based acidic bedding conditioner reduced environmental pathogens in sawdust bedding and teat ends without affecting teat end integrity. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Trends in the supply of California’s emergency departments and inpatient services, 2005–2014: a retrospective analysis

PubMed Central

Chow, Jessica L; Niedzwiecki, Matthew J; Hsia, Renee Y

2017-01-01

Objectives Given increasing demand for emergency care, there is growing concern over the availability of emergency department (ED) and inpatient resources. Existing studies of ED bed supply are dated and often overlook hospital capacity beyond ED settings. We described recent statewide trends in the capacity of ED and inpatient hospital services from 2005 to 2014. Design Retrospective analysis. Setting Using California hospital data, we examined the absolute and per admission changes in ED beds and inpatient beds in all hospitals from 2005 to 2014. Participants Our sample consisted of all patients inpatient and outpatient) from 501 hospital facilities over 10-year period. Outcome measures We analysed linear trends in the total annual ED visits, ED beds, licensed and staffed inpatient hospital beds and bed types, ED beds per ED visit, and inpatient beds per admission (ED and non-ED). Results Between 2005 and 2014, ED visits increased from 9.8 million to 13.2 million (an increase of 35.0%, p<0.001). ED beds also increased (by 29.8%, p<0.001), with an average annual increase of 195.4 beds. Despite this growth, ED beds per visit decreased by 3.9%, from 6.0 ED beds per 10 000 ED visits in 2005 to 5.8 beds in 2014 (p=0.01). While overall admission numbers declined by 4.9% (p=0.06), inpatient medical/surgical beds per visit grew by 11.3%, from 11.6 medical/surgical beds per 1000 admissions in 2005 to 12.9 beds in 2014 (p<0.001). However, there were reductions in psychiatric and chemical dependency beds per admission, by −15.3% (p<0.001) and −22.4% (p=0.05), respectively. Conclusions These trends suggest that, in its current state, inadequate supply of ED and specific inpatient beds cannot keep pace with growing patient demand for acute care. Analysis of ED and inpatient supply should capture dynamic variations in patient demand. Our novel ‘beds pervisit’ metric offers improvements over traditional supply measures. PMID:28495813

Use of soft hydrothermal processing to improve and recycle bedding for laboratory animals.

PubMed

Miyamoto, T; Li, Z; Kibushi, T; Yamasaki, N; Kasai, N

2008-10-01

Cage bedding for laboratory rodents can influence animal wellbeing and thus the experimental data. In addition, a large amount of used bedding containing excrement is discharged as medical waste from life science institutes and breeding companies. We developed a ground-breaking system to improve fresh bedding and recycle used bedding by applying a soft hydrothermal process with high-temperature and high-pressure dry steam. The system removes both harmful organic components and aromatic hydrocarbons that can affect animals' metabolism. The purpose of the present study was to evaluate the chemical and physical properties of the improved fresh bedding and the recycled used bedding treated by the system. The results showed that 68-99% of the predominant aromatic hydrocarbons were removed from fresh bedding treated at 0.35 MPa and 140 degrees C for 120 min ('improved bedding'). In addition, 59.4-99.0% of predominant harmful organic compounds derived from excrement were removed from used bedding treated at 0.45 MPa and 150 degrees C for 60 min ('recycled bedding'). The soft hydrothermal treatment increased the number of acidic functional groups on the bedding surface and gave it the high adsorptive efficiency of ammonia gas. Harmful substances such as microorganisms, heavy metals and pesticides decreased below the detection limit. The results clearly showed that the improved and recycled bedding is safer for laboratory rodents and has the potential to ameliorate conditions in primary and secondary enclosures (e.g. cages and animal rooms) used for maintaining laboratory animals. This process may be one of the most advanced techniques in providing an alternative to softwood and other bedding, economizing through the recycling of used bedding and reducing bedding waste from animal facilities.

Diagnosing binge eating disorder in a primary care setting.

PubMed

Montano, C Brendan; Rasgon, Natalie L; Herman, Barry K

2016-01-01

Binge eating disorder (BED), now recognized as a distinct eating disorder in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, is the most prevalent eating disorder. Although nearly half of individuals with BED are obese, BED also occurs in nonobese individuals. Despite the relatively high percentage of weight loss treatment-seeking individuals meeting BED criteria, primary care physicians may not be familiar with or have ever diagnosed BED. Many providers may also have difficulty distinguishing BED as a contributory factor in obesity. This review differentiates BED from other causes of obesity by describing how obese individuals with BED differ from obese individuals without BED and from nonobese individuals with BED in areas including psychopathology, behavior, genetics, physiology, quality of life and productivity. The ways in which health-care providers can identify individuals who may have BED are also highlighted so the proper course of treatment is pursued. Overall, obese individuals with BED demonstrate a number of key characteristics that differentiate them from obese individuals without eating disorders, including increased impulsivity in response to food stimuli with loss of control over eating, resulting in the consumption of more calories. They also experience significant guilt and other negative emotions following a meal. In addition, individuals with BED patients have more psychiatric comorbidity, display more psychopathology, exhibit longer binge durations, consume more meals as snacks during the day and have less dietary restraint compared with individuals with BED who are not obese. However, the differences between individuals with BED who are obese versus not obese are not as prominent. Taken together, the evidence appears to support the conclusion that BED is a unique and treatable neurobehavioral disorder associated with distinct behavioral and psychological profiles and distinct medical and functional outcomes, and that it is not merely a subtype of obesity.

Collaborative Strategy on Bed Bugs

EPA Pesticide Factsheets

The Collaborative Strategy on Bed Bugs was developed by the Federal Bed Bug Workgroup to clarify the federal role in bed bug control and highlight ways that government, community, academia and private industry can work together on bed bug issues.

'My friends love to tan': examining sensation seeking and the mediating role of association with friends who use tanning beds on tanning bed use intentions.

PubMed

Banerjee, Smita C; Greene, Kathryn; Bagdasarov, Zhanna; Campo, Shelly

2009-12-01

This paper explored how sensation seeking contributes to the likelihood of tanning bed use intentions both directly and indirectly through the way it shapes interaction with peers who use tanning beds and attitudes toward tanning bed. Eight hundred and ninety six (n = 896) male and female college students were recruited for the study. Measured variables included sensation seeking, association with friends who use tanning beds, attitudes toward tanning and tanning bed use intentions. Structural equation modeling was performed to test the hypotheses. In general, results supported the proposed hypotheses and documented that sensation seeking is indirectly associated with tanning bed use intentions through the mediation of association with peers who use tanning beds and attitudes toward tanning. The article discusses theoretical and methodological implications of the findings demonstrating the pathways of influence of sensation seeking on tanning bed use intentions.

The Safety of Hospital Beds

PubMed Central

Gervais, Pierre; Pooler, Charlotte; Merryweather, Andrew; Doig, Alexa K.; Bloswick, Donald

2015-01-01

To explore the safety of the standard and the low hospital bed, we report on a microanalysis of 15 patients’ ability to ingress, move about the bed, and egress. The 15 participants were purposefully selected with various disabilities. Bed conditions were randomized with side rails up or down and one low bed with side rails down. We explored the patients’ use of the side rails, bed height, ability to lift their legs onto the mattress, and ability to turn, egress, and walk back to the chair. The standard bed was too high for some participants, both for ingress and egress. Side rails were used by most participants when entering, turning in bed, and exiting. We recommend that side rails be reconsidered as a means to facilitate in-bed movement, ingress, and egress. Furthermore, single deck height settings for all patients are not optimal. Low beds as a safety measure must be re-evaluated. PMID:28462302

Exploring the Early Structure of a Rapidly Decompressed Particle Bed

NASA Astrophysics Data System (ADS)

Zunino, Heather; Adrian, R. J.; Clarke, Amanda; Johnson, Blair; Arizona State University Collaboration

2017-11-01

Rapid expansion of dense, pressurized beds of fine particles subjected to rapid reduction of the external pressure is studied in a vertical shock tube. A near-sonic expansion wave impinges on the particle bed-gas interface and rapidly unloads the particle bed. A high-speed video camera captures events occurring during bed expansion. The particle bed does not expand homogeneously, but breaks down into horizontal slabs and then transforms into a cellular-type structure. There are several key parameters that affect the particle bed evolution, including particle size and initial bed height. Analyses of this bed structure evolution from experiments with varying particle sizes and initial bed heights is presented. This work is supported by the U.S. Department of Energy, National Nuclear Security Administration, Advanced Simulation and Computing Program, as a Cooperative Agreement under the Predictive Science and Academic Alliance Program, under Contract No. DE-NA0002378.

Method of shielding a liquid-metal-cooled reactor

DOEpatents

Sayre, Robert K.

1978-01-01

The primary heat transport system of a nuclear reactor -- particularly for a liquid-metal-cooled fast-breeder reactor -- is shielded and protected from leakage by establishing and maintaining a bed of a powdered oxide closely and completely surrounding all components thereof by passing a gas upwardly therethrough at such a rate as to slightly expand the bed to the extent that the components of the system are able to expand without damage and yet the particles of the bed remain close enough so that the bed acts as a guard vessel for the system. Preferably the gas contains 1 to 10% oxygen and the gas is passed upwardly through the bed at such a rate that the lower portion of the bed is a fixed bed while the upper portion is a fluidized bed, the line of demarcation therebetween being high enough that the fixed bed portion of the bed serves as guard vessel for the system.

Hybrid fluidized bed combuster

DOEpatents

Kantesaria, Prabhudas P.; Matthews, Francis T.

1982-01-01

A first atmospheric bubbling fluidized bed furnace is combined with a second turbulent, circulating fluidized bed furnace to produce heat efficiently from crushed solid fuel. The bed of the second furnace receives the smaller sizes of crushed solid fuel, unreacted limestone from the first bed, and elutriated solids extracted from the flu gases of the first bed. The two-stage combustion of crushed solid fuel provides a system with an efficiency greater than available with use of a single furnace of a fluidized bed.

Solid fuel feed system for a fluidized bed

DOEpatents

Jones, Brian C.

1982-01-01

A fluidized bed for the combustion of coal, with limestone, is replenished with crushed coal from a system discharging the coal laterally from a station below the surface level of the bed. A compartment, or feed box, is mounted at one side of the bed and its interior separated from the bed by a weir plate beneath which the coal flows laterally into the bed while bed material is received into the compartment above the plate to maintain a predetermined minimum level of material in the compartment.

Fluid bed material transfer method

DOEpatents

Pinske, Jr., Edward E.

1994-01-01

A fluidized bed apparatus comprising a pair of separated fluid bed enclosures, each enclosing a fluid bed carried on an air distributor plate supplied with fluidizing air from below the plate. At least one equalizing duct extending through sidewalls of both fluid bed enclosures and flexibly engaged therewith to communicate the fluid beds with each other. The equalizing duct being surrounded by insulation which is in turn encased by an outer duct having expansion means and being fixed between the sidewalls of the fluid bed enclosures.

Apparatus and process for controlling fluidized beds

DOEpatents

Rehmat, Amirali G.; Patel, Jitendra G.

1985-10-01

An apparatus and process for control and maintenance of fluidized beds under non-steady state conditions. An ash removal conduit is provided for removing solid particulates from a fluidized bed separate from an ash discharge conduit in the lower portion of the grate supporting such a bed. The apparatus and process of this invention is particularly suitable for use in ash agglomerating fluidized beds and provides control of the fluidized bed before ash agglomeration is initiated and during upset conditions resulting in stable, sinter-free fluidized bed maintenance.

Apparatus for controlling fluidized beds

DOEpatents

Rehmat, Amirali G.; Patel, Jitendra G.

1987-05-12

An apparatus and process for control and maintenance of fluidized beds under non-steady state conditions. An ash removal conduit is provided for removing solid particulates from a fluidized bed separate from an ash discharge conduit in the lower portion of the grate supporting such a bed. The apparatus and process of this invention is particularly suitable for use in ash agglomerating fluidized beds and provides control of the fluidized bed before ash agglomeration is initiated and during upset conditions resulting in stable, sinter-free fluidized bed maintenance.

Paediatric burn unit in Portugal: Beds needed using a bed-day approach.

PubMed

Santos, João V; Viana, João; Amarante, José; Freitas, Alberto

2017-03-01

Despite the high burden of children with burns, there is not a paediatric burn unit (PBU) in Portugal. We aimed to estimate the Portuguese health care providing needs on paediatric burns. We performed a nation-wide retrospective study, between 2009 and 2013, among less than 16 years-old inpatients with burns that met the transfer criteria to a burn unit in Portugal. A bed-day approach was used, targeting an occupancy rate of 70-75%, and possible locations were studied. The primary outcome was the number of beds needed, and secondary outcomes were the overload and revenue for each possible number of beds in a PBU. A total of 1155 children met the transfer criteria to a burn unit, representing a total of 17,371 bed-days. Occupancy rates of 11-bed, 12-bed, 13-bed and 14-bed PBU were, respectively, 79.7%, 75.3%, 71.0% and 66.8%. The 13-bed PBU scenario would represent an overload of 523 bed-days, revenue of more than 5 million Euros and a ratio of 1 PBU bed per 123,409 children. Using a groundbreaking approach, the optimal number of PBU beds needed in Portugal is 13. However, as half of the patients who met burn transfer criteria are not transferred, this bed number might be overestimated if this pattern maintains, despite the underestimation with our method approach. If a PBU is to be created the preferable location is Porto. Cost-effectiveness studies should be performed. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.

Implications of lessons learned from tobacco control for tanning bed reform.

PubMed

Sinclair, Craig; Makin, Jennifer K

2013-01-01

Tanning beds used according to the manufacturer's instructions expose the user to health risks, including melanoma and other skin cancers. Applying the MPOWER model (monitor, protect, offer alternatives, warn, enforce, and raise taxes), which has been used in tobacco control, to tanning bed reform could reduce the number of people at risk of diseases associated with tanning bed use. Among the tactics available to government are restricting the use of tanning beds by people under age 18 and those with fair skin, increasing the price of tanning bed services through taxation, licensing tanning bed operators, and banning unsupervised tanning bed operations.

Implications of Lessons Learned From Tobacco Control for Tanning Bed Reform

PubMed Central

Sinclair, Craig

2013-01-01

Tanning beds used according to the manufacturer’s instructions expose the user to health risks, including melanoma and other skin cancers. Applying the MPOWER model (monitor, protect, offer alternatives, warn, enforce, and raise taxes), which has been used in tobacco control, to tanning bed reform could reduce the number of people at risk of diseases associated with tanning bed use. Among the tactics available to government are restricting the use of tanning beds by people under age 18 and those with fair skin, increasing the price of tanning bed services through taxation, licensing tanning bed operators, and banning unsupervised tanning bed operations. PMID:23449282

Method of burning sulfur-containing fuels in a fluidized bed boiler

DOEpatents

Jones, Brian C.

1982-01-01

A method of burning a sulfur-containing fuel in a fluidized bed of sulfur oxide sorbent wherein the overall utilization of sulfur oxide sorbent is increased by comminuting the bed drain solids to a smaller average particle size, preferably on the order of 50 microns, and reinjecting the comminuted bed drain solids into the bed. In comminuting the bed drain solids, particles of spent sulfur sorbent contained therein are fractured thereby exposing unreacted sorbent surface. Upon reinjecting the comminuted bed drain solids into the bed, the newly-exposed unreacted sorbent surface is available for sulfur oxide sorption, thereby increasing overall sorbent utilization.

Testing a Threshold-Based Bed Bug Management Approach in Apartment Buildings.

PubMed

Singh, Narinderpal; Wang, Changlu; Zha, Chen; Cooper, Richard; Robson, Mark

2017-07-26

We tested a threshold-based bed bug ( Cimex lectularius L.) management approach with the goal of achieving elimination with minimal or no insecticide application. Thirty-two bed bug infested apartments were identified. These apartments were divided into four treatment groups based on apartment size and initial bed bug count, obtained through a combination of visual inspection and bed bug monitors: I- Non-chemical only in apartments with 1-12 bed bug count, II- Chemical control only in apartments with 1-12 bed bug count, III- Non-chemical and chemical control in apartments with >12 bed bug count, and IV- Chemical control only in apartments with ≥11 bed bug count. All apartments were monitored or treated once every two weeks for a maximum of 28 wk. Treatment I eliminated bed bugs in a similar amount of time to treatment II. Time to eliminate bed bugs was similar between treatment III and IV but required significantly less insecticide spray in treatment III than that in treatment IV. A threshold-based management approach (non-chemical only or non-chemical and chemical) can eliminate bed bugs in a similar amount of time, using little to no pesticide compared to a chemical only approach.

Mechanical stratigraphic controls on natural fracture spacing and penetration

NASA Astrophysics Data System (ADS)

McGinnis, Ronald N.; Ferrill, David A.; Morris, Alan P.; Smart, Kevin J.; Lehrmann, Daniel

2017-02-01

Fine-grained low permeability sedimentary rocks, such as shale and mudrock, have drawn attention as unconventional hydrocarbon reservoirs. Fracturing - both natural and induced - is extremely important for increasing permeability in otherwise low-permeability rock. We analyze natural extension fracture networks within a complete measured outcrop section of the Ernst Member of the Boquillas Formation in Big Bend National Park, west Texas. Results of bed-center, dip-parallel scanline surveys demonstrate nearly identical fracture strikes and slight variation in dip between mudrock, chalk, and limestone beds. Fracture spacing tends to increase proportional to bed thickness in limestone and chalk beds; however, dramatic differences in fracture spacing are observed in mudrock. A direct relationship is observed between fracture spacing/thickness ratio and rock competence. Vertical fracture penetrations measured from the middle of chalk and limestone beds generally extend to and often beyond bed boundaries into the vertically adjacent mudrock beds. In contrast, fractures in the mudrock beds rarely penetrate beyond the bed boundaries into the adjacent carbonate beds. Consequently, natural bed-perpendicular fracture connectivity through the mechanically layered sequence generally is poor. Fracture connectivity strongly influences permeability architecture, and fracture prediction should consider thin bed-scale control on fracture heights and the strong lithologic control on fracture spacing.

Efficacy of three different steamers for control of bed bugs (Cimex lectularius L.).

PubMed

Wang, Desen; Wang, Changlu; Wang, Guohong; Zha, Chen; Eiden, Amanda L; Cooper, Richard

2018-04-15

Bed bugs, Cimex lectularius L., have become one of the most difficult urban pests to control. Steam treatment is reported to be an effective method to kill bed bugs and is considered to be an important component of bed bug integrated pest management (IPM). We evaluated and compared the efficacy of two affordable consumer-grade commercial steamers to a commonly used professional-grade steamer for killing bed bugs. In laboratory experiments, the consumer-grade steamer at an affordable price achieved the same high control efficacy as the professional-grade steamer for treating bed bugs exposed on mattresses (100% bed bug mortality), located beneath a fabric cover (>89% bed bug mortality), or hiding in cracks (100% bed bug mortality). Bed bugs located behind a leather cover did not suffer significant mortality from steam treatment regardless of the type of steamers used and treatment duration. Proper use of steamers can kill all life stages of bed bugs. Affordable consumer-grade steamers are as effective as professional-grade steam machines for eliminating bed bugs resting on mattresses, hiding behind fabric materials, or in cracks. This article is protected by copyright. All rights reserved.

Tanning beds: A call to action for further educational and legislative efforts.

PubMed

Farley, Clara; Alimi, Yewande; Espinosa, Lauren R; Perez, Sebastian; Knechtle, William; Hestley, Andrea; Carlson, Grant W; Russell, Maria C; Delman, Keith A; Rizzo, Monica

2015-08-01

Melanoma is steadily increasing over the past decade. Recent studies confirmed a link between tanning bed use and melanoma. We sought to determine the prevalence and frequency of tanning bed among young patients with melanoma. We retrospectively analyzed tanning bed use among young melanoma patients compared to controls selected from the hospital medical records. A telephone survey investigated family history of melanoma or skin cancer, hair color, eye color, skin type, tanning bed use, and patient awareness of dangers of tanning bed use. A total of 601 melanoma cases were identified; 265 (44%) completed the telephone survey as did 195 (31%) controls. Of these 460 subjects, 260 were female. Females were 3.0 times more likely to have used a tanning bed. Melanoma patients had natural light color hair, blue-green eyes, and 2.0 times more likely to use a tanning bed than controls. Among the tanning bed users, 90% were aware of danger of tanning bed. Our study found that tanning beds were more likely to be used by young women, the majority of whom are aware of the associated risks. Eliminating the use of tanning beds should be considered to decrease the incidence of melanoma. © 2015 Wiley Periodicals, Inc.

Testing a Threshold-Based Bed Bug Management Approach in Apartment Buildings

PubMed Central

Singh, Narinderpal; Zha, Chen; Cooper, Richard; Robson, Mark

2017-01-01

We tested a threshold-based bed bug (Cimex lectularius L.) management approach with the goal of achieving elimination with minimal or no insecticide application. Thirty-two bed bug infested apartments were identified. These apartments were divided into four treatment groups based on apartment size and initial bed bug count, obtained through a combination of visual inspection and bed bug monitors: I- Non-chemical only in apartments with 1–12 bed bug count, II- Chemical control only in apartments with 1–12 bed bug count, III- Non-chemical and chemical control in apartments with >12 bed bug count, and IV- Chemical control only in apartments with ≥11 bed bug count. All apartments were monitored or treated once every two weeks for a maximum of 28 wk. Treatment I eliminated bed bugs in a similar amount of time to treatment II. Time to eliminate bed bugs was similar between treatment III and IV but required significantly less insecticide spray in treatment III than that in treatment IV. A threshold-based management approach (non-chemical only or non-chemical and chemical) can eliminate bed bugs in a similar amount of time, using little to no pesticide compared to a chemical only approach. PMID:28933720

Dosimetric quality endpoints for low-dose-rate prostate brachytherapy using biological effective dose (bed) vs. conventional dose

DOE Office of Scientific and Technical Information (OSTI.GOV)

Singh, Rachana; Al-Hallaq, Hania; Pelizzari, Charles A.

2003-12-31

The purpose of this study was to compare conventional low-dose-rate prostate brachytherapy dosimetric quality parameters with their biological effective dose (BED) counterparts. To validate a model for transformation from conventional dose to BED, the postimplant plans of 31 prostate brachytherapy patients were evaluated using conventional dose-volume histogram (DVH) quality endpoints and analogous BED-DVH endpoints. Based on CT scans obtained 4 weeks after implantation, DVHs were computed and standard dosimetric endpoints V100 (volume receiving 100% of the prescribed dose), V150, V200, HI (1-[V150/V100]), and D90 (dose that 90% of the target volume received) were obtained for quality analysis. Using known andmore » reported transformations, dose grids were transformed to BED-early ({alpha}/{beta} = 10 Gy) and BED-late ({alpha}/{beta} = 3 Gy) grids, and the same dosimetric endpoints were analyzed. For conventional, BED-early and BED-late DVHs, no differences in V100 were seen (0.896, 0.893, and 0.894, respectively). However, V150 and V200 were significantly higher for both BED-early (0.582 and 0.316) and BED-late (0.595 and 0.337), compared with the conventional (0.539 and 0.255) DVHs. D90 was significantly lower for the BED-early (103.1 Gy) and BED-late transformations (106.9 Gy) as compared with the conventional (119.5 Gy) DVHs. The conventional prescription parameter V100 is the same for the corresponding BED-early and BED-late transformed DVHs. The toxicity parameters V150 and V200 are slightly higher using the BED transformations, suggesting that the BED doses are somewhat higher than predicted using conventional DVHs. The prescription/quality parameter D90 is slightly lower, implying that target coverage is lower than predicted using conventional DVHs. This methodology can be applied to analyze BED dosimetric endpoints to improve clinical outcome and reduce complications of prostate brachytherapy.« less

Discrete Element Modeling of the Mobilization of Coarse Gravel Beds by Finer Gravel Particles

NASA Astrophysics Data System (ADS)

Hill, K. M.; Tan, D.

2012-12-01

Recent research has shown that the addition of fine gravel particles to a coarse bed will mobilize the coarser bed, and that the effect is sufficiently strong that a pulse of fine gravel particles can mobilize an impacted coarser bed. Recent flume experiments have demonstrated that the degree of bed mobilization by finer particles is primarily dependent on the particle size ratio of the coarse and fine particles, rather than absolute size of either particle, provided both particles are sufficiently large. However, the mechanism behind the mobilization is not understood. It has previously been proposed that the mechanism is driven by a combination of geometric effects and hydraulic effects. For example, it has been argued that smaller particles fill in gaps along the bed, resulting in a smoother bed over which the larger particles are less likely to be disentrained and a reduced near-bed flow velocity and subsequent increased drag on protruding particles. Altered near-bed turbulence has also been cited as playing an important role. We perform simulations using the discrete element method with one-way fluid-solid coupling to conduct simulations of mobilization of a gravel bed by fine gravel particles. By independently and artificially controlling average and fluctuating velocity profiles, we systematically investigate the relative role that may be played by particle-particle interactions, average near-bed velocity profiles, and near-bed turbulence statistics. The simulations indicate that the relative importance of these mechanisms changes with the degree of mobilization of the bed. For higher bed mobility similar to bed sheets, particle-particle interactions, plays a significant role in an apparent rheology in the bed sheets, not unlike that observed in a dense granular flow of particles of different sizes. For conditions closer to a critical shear stress for bedload transport, the near-bed velocity profiles and turbulence statistics become increasingly important.

Cognitive Rationalizations for Tanning-Bed Use: A Preliminary Exploration

PubMed Central

Banerjee, Smita C.; Hay, Jennifer L.; Greene, Kathryn

2016-01-01

Objectives To examine construct and predictive utility of an adapted cognitive rationalization scale for tanning-bed use. Methods Current/former tanning-bed-using undergraduate students (N = 216; 87.6% females; 78.4% white) at a large northeastern university participated in a survey. A cognitive rationalization for tanning-bed use scale was adapted. Standardized self-report measures of past tanning-bed use, advantages of tanning, perceived vulnerability to photoaging, tanning-bed use dependence, and tanning- bed use intention were also administered. Results The cognitive rationalization scale exhibited strong construct and predictive validity. Current tanners and tanning-bed-use-dependent participants endorsed rationalizations more strongly than did former tanners and not-tanning-bed-use-dependent participants respectively. Conclusions Findings indicate that cognitive rationalizations help explain discrepancy between inconsistent cognitions. PMID:23985280

Updated Performance Evaluation of the ISS Water Processor Multifiltration Beds

NASA Technical Reports Server (NTRS)

Bowman, Elizabeth M.; Carter, Layne; Carpenter, Joyce; Orozco, Nicole; Weir, Natalee; Wilson, Mark

2014-01-01

The ISS Water Processor Assembly (WPA) produces potable water from a waste stream containing humidity condensate and urine distillate. The primary treatment process is achieved in the Multifiltration Beds, which include adsorbent media and ion exchange resin for the removal of dissolved organic and inorganic contaminants. Two Multifiltration Beds (MF Beds) were replaced on ISS in July 2010 after initial indication of inorganic breakthrough of the first bed and an increasing Total Organic Carbon (TOC) trend in the product water. The first bed was sampled and analyzed Sept 2011 through March 2012. The second MF Bed was sampled and analyzed June 2012 through August 2012. The water resident in the both beds was analyzed for various parameters to evaluate adsorbent loading, performance of the ion exchange resin, microbial activity, and generation of leachates from the ion exchange resin. Portions of the adsorbent media and ion exchange resin were sampled and subsequently desorbed to identify the primary contaminants removed at various points in the bed in addition to microbial analysis. Analysis of the second bed will be compared to results from the first bed to provide a comprehensive overview of how the Multifiltration Beds function on orbit. New data from the second bed supplements the analysis of the first bed (previously reported) and gives a more complete picture of breakthrough compounds, resin breakdown products, microbial activity, and difficult to remove compounds. The results of these investigations and implications to the operation of the WPA on ISS are documented in this paper.

77 FR 12182 - Safety Standard for Portable Bed Rails: Final Rule

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-29

... of ASTM F2085- 10a, comply with the following: (i) 1.4.1 Foam and inflatable bed rails need meet only...--portable bed rail constructed primarily of nonrigid materials such as fabric or foam. 3.1.11 inflatable bed..., inflatable bed rail, are terms that are now incorporated as non-rigid bed rail under new section 3.1.12 in...

Role of Vision and Mechanoreception in Bed Bug, Cimex lectularius L. Behavior

PubMed Central

Singh, Narinderpal; Wang, Changlu; Cooper, Richard

2015-01-01

The role of olfactory cues such as carbon dioxide, pheromones, and kairomones in bed bug, Cimex lectularius L. behavior has been demonstrated. However, the role of vision and mechanoreception in bed bug behavior is poorly understood. We investigated bed bug vision by determining their responses to different colors, vertical objects, and their ability to detect colors and vertical objects under low and complete dark conditions. Results show black and red paper harborages are preferred compared to yellow, green, blue, and white harborages. A bed bug trapping device with a black or red exterior surface was significantly more attractive to bed bugs than that with a white exterior surface. Bed bugs exhibited strong orientation behavior toward vertical objects. The height (15 vs. 30 cm tall) and color (brown vs. black) of the vertical object had no significant effect on orientation behavior of bed bugs. Bed bugs could differentiate color and detect vertical objects at very low background light conditions, but not in complete darkness. Bed bug preference to different substrate textures (mechanoreception) was also explored. Bed bugs preferred dyed tape compared to painted tape, textured painted plastic, and felt. These results revealed that substrate color, presence of vertical objects, and substrate texture affect host-seeking and harborage-searching behavior of bed bugs. Bed bugs may use a combination of vision, mechanoreception, and chemoreception to locate hosts and seek harborages. PMID:25748041

Coevolution of bed surface patchiness and channel morphology: 2. Numerical experiments

USGS Publications Warehouse

Nelson, Peter A.; McDonald, Richard R.; Nelson, Jonathan M.; Dietrich, William E.

2015-01-01

In gravel bed rivers, bed topography and the bed surface grain size distribution evolve simultaneously, but it is not clear how feedbacks between topography and grain sorting affect channel morphology. In this, the second of a pair of papers examining interactions between bed topography and bed surface sorting in gravel bed rivers, we use a two-dimensional morphodynamic model to perform numerical experiments designed to explore the coevolution of both free and forced bars and bed surface patches. Model runs were carried out on a computational grid simulating a 200 m long, 2.75 m wide, straight, rectangular channel, with an initially flat bed at a slope of 0.0137. Over five numerical experiments, we varied (a) whether an obstruction was present, (b) whether the sediment was a gravel mixture or a single size, and (c) whether the bed surface grain size feeds back on the hydraulic roughness field. Experiments with channel obstructions developed a train of alternate bars that became stationary and were connected to the obstruction. Freely migrating alternate bars formed in the experiments without channel obstructions. Simulations incorporating roughness feedbacks between the bed surface and flow field produced flatter, broader, and longer bars than simulations using constant roughness or uniform sediment. Our findings suggest that patches are not simply a by-product of bed topography, but they interact with the evolving bed and influence morphologic evolution.

Binge eating disorder and obesity: preliminary evidence for distinct cardiovascular and psychological phenotypes.

PubMed

Klatzkin, Rebecca R; Gaffney, Sierra; Cyrus, Kathryn; Bigus, Elizabeth; Brownley, Kimberly A

2015-04-01

This study investigated cardiovascular functioning, mood, and eating-related psychological factors at rest and in response to mental stress in three groups of women: 1) Obese women with binge eating disorder (BED; n=9); 2) obese non-BED women (n=15); and 3) normal weight (NW) non-BED women (n=15). Compared to both obese and NW non-BED women, obese women with BED showed heightened overall blood pressure and reported greater depression symptoms, perceived stress, and eating-related psychopathology. Additionally, obese women with BED reported greater overall negative affect and state anxiety compared to obese non-BED women. The heart rate response to stress was blunted in the obese BED group compared to the other groups, but this effect was no longer significant after controlling for baseline differences in depression. Correlational analyses revealed a positive association between stress-induced changes in hunger and cardiovascular measures only in obese women with BED. Longitudinal studies are needed to determine if stress dysregulation and stress-induced increases in hunger contribute to the onset and/or maintenance of BED. In particular, studies utilizing an additional NW BED control group are warranted in order to further examine the impact of BED above and beyond the impact of obesity on psychophysiological functioning and to inform the growing literature regarding stress-related factors that distinguish the BED and obesity phenotypes. Copyright © 2015 Elsevier Inc. All rights reserved.

Role of vision and mechanoreception in bed bug, Cimex lectularius L. behavior.

PubMed

Singh, Narinderpal; Wang, Changlu; Cooper, Richard

2015-01-01

The role of olfactory cues such as carbon dioxide, pheromones, and kairomones in bed bug, Cimex lectularius L. behavior has been demonstrated. However, the role of vision and mechanoreception in bed bug behavior is poorly understood. We investigated bed bug vision by determining their responses to different colors, vertical objects, and their ability to detect colors and vertical objects under low and complete dark conditions. Results show black and red paper harborages are preferred compared to yellow, green, blue, and white harborages. A bed bug trapping device with a black or red exterior surface was significantly more attractive to bed bugs than that with a white exterior surface. Bed bugs exhibited strong orientation behavior toward vertical objects. The height (15 vs. 30 cm tall) and color (brown vs. black) of the vertical object had no significant effect on orientation behavior of bed bugs. Bed bugs could differentiate color and detect vertical objects at very low background light conditions, but not in complete darkness. Bed bug preference to different substrate textures (mechanoreception) was also explored. Bed bugs preferred dyed tape compared to painted tape, textured painted plastic, and felt. These results revealed that substrate color, presence of vertical objects, and substrate texture affect host-seeking and harborage-searching behavior of bed bugs. Bed bugs may use a combination of vision, mechanoreception, and chemoreception to locate hosts and seek harborages.

Apparatus for controlling fluidized beds

DOEpatents

Rehmat, A.G.; Patel, J.G.

1987-05-12

An apparatus and process are disclosed for control and maintenance of fluidized beds under non-steady state conditions. An ash removal conduit is provided for removing solid particulates from a fluidized bed separate from an ash discharge conduit in the lower portion of the grate supporting such a bed. The apparatus and process of this invention is particularly suitable for use in ash agglomerating fluidized beds and provides control of the fluidized bed before ash agglomeration is initiated and during upset conditions resulting in stable, sinter-free fluidized bed maintenance. 2 figs.

Cross-bedding Related Anisotropy and its Role in the Orientation of Joints in an Aeolian Sandstone

NASA Astrophysics Data System (ADS)

Deng, S.; Cilona, A.; Mapeli, C.; Panfilau, A.; Aydin, A.; Prasad, M.

2014-12-01

Previous research revealed that the cross-bedding related anisotropy in aeolian sandstones affects the orientation of compaction bands, also known as anticracks. We hypothesize that cross-bedding should a have similar influence on the orientation of the joints within the same rock at the same location. To test this hypothesis, we investigated the relationship between the cross-beds and the cross-bed package confined joints in the Jurassic aeolian Aztec Sandstone cropping out in the Valley of Fire State Park, Nevada. The field data demonstrates that the cross-bed package confined joints occur at high-angle to bedding and trend roughly parallel to the dip direction of the cross-beds. This shows that the cross-bed orientation and the associated anisotropy also exert a strong control on the formation and orientation of the joints. In order to characterize the anisotropy due to cross-bedding in the Aztec Sandstone, we measured the P-wave velocities parallel and perpendicular to bedding from 11 samples in the laboratory using a bench-top ultrasonic assembly. The measured P-wave anisotropy is about 13% on average. Based on these results, a numerical model based on the generalized Hooke's law for anisotropic materials is analyzed assuming the cross-bedded sandstone to be transversely isotropic. Using this model, we tested various cross-bed orientations as well as different strain boundary conditions (uniaxial, axisymmetric and triaxial). It is possible to define a boundary condition under which the modeled results roughly match with the observed relationship between cross-bed package confined joints and cross-beds. These results have important implications for fluid flow through aeolian sandstones in reservoirs and aquifers.

Bed sharing among mother-infant pairs in Klang district, Peninsular Malaysia and its relationship to breast-feeding.

PubMed

Tan, Kok Leong

2009-10-01

The aim of the study was to determine the prevalence of mother-infant bed sharing in Klang district, Peninsular Malaysia and to identify factors associated with bed sharing. This was a cross-sectional study involving 682 mother-infant pairs with infants up to 6 months attending government clinics in Klang district, Peninsular Malaysia. Data were collected by face-to-face interview using a pretested structured questionnaire for a 4-month period in 2006. Data regarding maternal, paternal, obstetric, infant, occupancy, breast-feeding characteristics, and bed-sharing practice were collected. Data on bed sharing were based on practice in the past 1-month period. Bed sharing was defined as an infant sharing a bed with mother, and infant must be within arms reach from the mother, whereas a bed was defined as either a sleeping mattress placed on a bed frame or placed on the floor. The prevalence of bed sharing was estimated. Relationship and magnitude of association between independent factors and bed sharing were examined using odds ratio and 95% confidence interval. Logistic regression analysis was used to control for confounding factors. The prevalence of bed sharing among mothers with infants aged between 1 and 6 months was 73.5% (95% confidence interval: 70.0-76.7). In multivariate analysis, urban/rural differences, mothers' ethnicity, occupation, family income, husbands' support on bed sharing, number of children younger than 12 years staying in the house, and breast-feeding were associated with bed sharing. These factors need to be considered in analyzing the overall risks and benefits of bed sharing, paying attention to breastfeeding practices.

Mineral resources of the Devil's Garden Lava Bed, Squaw Ridge Lava Bed, and Four Craters Lava Bed Wilderness Study Areas, Lake County, Oregon

DOE Office of Scientific and Technical Information (OSTI.GOV)

Keith, W.J.; King, H.D.; Gettings, M.E.

1988-01-01

The Devel's Garden lava Bed, Squaw Ridge Lava Bed, and Four Craters Lava Bed Wilderness Study Areas include approximately 70,940 acres and are underlain entirely by Pleistocene or Holocene lava flows and associated sediments. There is no evidence of hydrothermal alteration in the study areas. No resources were identified in the study areas, but there is low potential for perlite resources in the southern part of the Devil's Garden Lava Bed and the northern half of the Squaw Ridge Lava Bed areas. All three study areas have low potential for geothermal resources and for oil and gas resources.

Geometry and controls on the development of igneous sill-related forced folds: 2D seismic reflection case study from offshore Southern Australia

NASA Astrophysics Data System (ADS)

Jackson, Christopher; Schofield, Nick; Magee, Craig; Golenkov, Bogdan

2017-04-01

Emplacement of magma in the shallow subsurface can result in the development of dome-shaped folds at the Earth's surface. These so-called 'forced folds' have been described in the field and in subsurface datasets, although the exact geometry of the folds and the nature of their relationship to underlying sills remains unclear and, in some cases, controversial. As a result, the utility of these features in tracking the subsurface movement of magma, and predicting the potential size and location of potentially hazardous volcanic eruptions, is uncertain. Here we use high-quality, 2D seismic reflection and borehole data from the Ceduna sub-basin, offshore southern Australia to describe the structure and infer the evolution of igneous sill-related forced folds in the Bight Basin Igneous Complex (BBIC). We mapped 33 igneous sills, which were emplaced 200-1500 m below the palaeo-seabed in an Upper Cretaceous, coal-bearing, predominantly coastal-plain succession. The intrusions, which are expressed as packages of high-amplitude reflections, are 32-250 m thick and 7-19 km in diameter. They are overlain by dome-shaped folds, which are up to 17 km wide and display up to 210 m of relief. The edges of these folds coincide with the margins of the underlying sills and the folds display the greatest relief where the underlying sills are thickest; the folds are therefore interpreted as forced folds that formed in response to emplacement of magma in the shallow subsurface. The folds are onlapped by Lutetian (middle Eocene) strata, indicating they formed and the intrusions were emplaced during the latest Ypresian (c. 48 Ma). We demonstrate that fold amplitude is typically less than sill thickness even for sills with very large diameter-to-depth ratios, suggesting that pure elastic bending (forced folding) of the overburden is not the only process accommodating magma emplacement, and that supra-sill compaction may be important even at relatively shallow depths. Based on the observation that the sills intruded a shallowly-buried succession, the discrepancy between fold amplitude and sill thickness may reflect loss of host rock volume by fluidisation and pore fluid expulsion from poorly-lithified, water-rich beds. This study indicates that host rock composition, emplacement depth and deformation mechanisms are important controls on the style of deformation that occurs during intrusive igneous activity, and that forced fold amplitude may not always reflect the thickness of an underlying igneous intrusion. In addition, the results of this study suggest that physical and numerical models need to model more complex host rock stratigraphies and rheologies if they wish to capture the full range of deformation mechanisms that occur during magma emplacement in the Earth's shallow subsurface.

High-Flux, High Performance H2O2 Catalyst Bed for ISTAR

NASA Technical Reports Server (NTRS)

Ponzo, J.

2005-01-01

On NASA's ISTAR RBCC program packaging and performance requirements exceeded traditional H2O2 catalyst bed capabilities. Aerojet refined a high performance, monolithic 90% H202 catalyst bed previously developed and demonstrated. This approach to catalyst bed design and fabrication was an enabling technology to the ISTAR tri-fluid engine. The catalyst bed demonstrated 55 starts at throughputs greater than 0.60 lbm/s/sq in for a duration of over 900 seconds in a physical envelope approximately 114 of traditional designs. The catalyst bed uses photoetched plates of metal bonded into a single piece monolithic structure. The precise control of the geometry and complete mixing results in repeatable, quick starting, high performing catalyst bed. Three different beds were designed and tested, with the best performing bed used for tri-fluid engine testing.

77 FR 18793 - Spectrum Sharing Innovation Test-Bed Pilot Program

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-28

.... 120322212-2212-01] Spectrum Sharing Innovation Test-Bed Pilot Program AGENCY: National Telecommunications... Innovation Test-Bed pilot program to assess whether devices employing Dynamic Spectrum Access techniques can... Spectrum Sharing Innovation Test-Bed (Test-Bed) pilot program to examine the feasibility of increased...

The effect of bedding system selected by manual muscle testing on sleep-related cardiovascular functions.

PubMed

Kuo, Terry B J; Li, Jia-Yi; Lai, Chun-Ting; Huang, Yu-Chun; Hsu, Ya-Chuan; Yang, Cheryl C H

2013-01-01

Different types of mattresses affect sleep quality and waking muscle power. Whether manual muscle testing (MMT) predicts the cardiovascular effects of the bedding system was explored using ten healthy young men. For each participant, two bedding systems, one inducing the strongest limb muscle force (strong bedding system) and the other inducing the weakest limb force (weak bedding system), were identified using MMT. Each bedding system, in total five mattresses and eight pillows of different firmness, was used for two continuous weeks at the participant's home in a random and double-blind sequence. A sleep log, a questionnaire, and a polysomnography were used to differentiate the two bedding systems. Heart rate variability and arterial pressure variability analyses showed that the strong bedding system resulted in decreased cardiovascular sympathetic modulation, increased cardiac vagal activity, and increased baroreceptor reflex sensitivity during sleep as compared to the weak bedding system. Different bedding systems have distinct cardiovascular effects during sleep that can be predicted by MMT.

The Effect of Bedding System Selected by Manual Muscle Testing on Sleep-Related Cardiovascular Functions

PubMed Central

Kuo, Terry B. J.; Li, Jia-Yi; Lai, Chun-Ting; Huang, Yu-Chun; Hsu, Ya-Chuan; Yang, Cheryl C. H.

2013-01-01

Background. Different types of mattresses affect sleep quality and waking muscle power. Whether manual muscle testing (MMT) predicts the cardiovascular effects of the bedding system was explored using ten healthy young men. Methods. For each participant, two bedding systems, one inducing the strongest limb muscle force (strong bedding system) and the other inducing the weakest limb force (weak bedding system), were identified using MMT. Each bedding system, in total five mattresses and eight pillows of different firmness, was used for two continuous weeks at the participant's home in a random and double-blind sequence. A sleep log, a questionnaire, and a polysomnography were used to differentiate the two bedding systems. Results and Conclusion. Heart rate variability and arterial pressure variability analyses showed that the strong bedding system resulted in decreased cardiovascular sympathetic modulation, increased cardiac vagal activity, and increased baroreceptor reflex sensitivity during sleep as compared to the weak bedding system. Different bedding systems have distinct cardiovascular effects during sleep that can be predicted by MMT. PMID:24371836

Reduction of FeO contents in sinter under high bed operation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fujii, K.; Hazama, K.; Hoshikuma, Y.

1996-12-31

High-bed operation (bed height more than 700 mm) is currently being carried out at the Kure No. 1 sintering plant. Before initiating this high-bed operation, the authors conducted sinter pot tests at various bed heights to investigate the effect of bed height on sintering. The following results were obtained from these pot tests: Heightening of the sinter bed increased yield at the upper layer, but at the lower layer, the yield reached a maximum value at a certain bed height. From observation of the sinter cakes, the reduction in yield is attributed to uneven burn caused by surplus heat atmore » the lower layers. Therefore, when high-bed operation is carried out, reduction of the burning energy (reduction of the FeO content in the sinter) is required. This high-bed operation with lower FeO content has enabled the company to reduce fuel consumption and SiO{sub 2} content, while maintaining high yield and high sinter quality.« less

Stress-induced laboratory eating behavior in obese women with binge eating disorder.

PubMed

Laessle, Reinhold G; Schulz, Simone

2009-09-01

To compare the microstructural eating behavior of obese patients with and without binge eating disorder (BED) after stress induction in laboratory. Forty-eight obese women were investigated. Seventeen were assigned to the group of BED. Group (BED vs. non-BED) by condition (stress vs. no stress) interaction effect on feeding variables, measured by a universal eating monitor, was tested. Stress was induced by the trier social stress test (TSST) and chocolate pudding served as laboratory food. From the nonstress to the stress condition, patients with BED, when compared with non-BED had a greater increase in average eating rate (p < .01) and a corresponding greater increase in the frequency of spoonfuls (p < .02). The BED group also showed a different change in acceleration/deceleration from the nonstress to the stress condition compared to the non-BED group (p < .04). Obese individuals with BED appear to exhibit a different response to stress than obese non-BED individuals and individuals with bulimia nervosa.

Response of bed mobility to sediment supply in natural gravel bed channels: A detailed examination and evaluation of mobility parameters

Treesearch

T. E. Lisle; J. M. Nelson; B. L. Barkett; J. Pitlick; M. A. Madej

1998-01-01

Recent laboratory experiments have shown that bed mobility in gravel bed channels responds to changes in sediment supply, but detailed examinations of this adjustment in natural channels have been lacking, and practical methodologies to measure bed mobility have not been tested. We examined six gravel-bed, alternate-bar channels which have a wide range in annual...

Separation of particulate from flue gas of fossil fuel combustion and gasification

DOEpatents

Yang, W.C.; Newby, R.A.; Lippert, T.E.

1997-08-05

The gas from combustion or gasification of fossil fuel contains fly ash and other particulates. The fly ash is separated from the gas in a plurality of standleg moving granular-bed filter modules. Each module includes a dipleg through which the bed media flows into the standleg. The bed media forms a first filter bed having an upper mass having a first frusto-conical surface in a frusto-conical member at the entrance to the standleg and a lower mass having a second frusto-conical surface of substantially greater area than the first surface after it passes through the standleg. A second filter media bed may be formed above the first filter media bed. The gas is fed tangentially into the module above the first surface. The fly ash is captured on the first frusto-conical surface and within the bed mass. The processed gas flows out through the second frusto-conical surface and then through the second filter bed, if present. The bed media is cleaned of the captured fly ash and recirculated to the moving granular bed filter. Alternatively, the bed media may be composed of the ash from the combustion which is pelletized to form agglomerates. The ash flows through the bed only once; it is not recycled. 11 figs.

Separation of particulate from flue gas of fossil fuel combustion and gasification

DOEpatents

Yang, Wen-Ching; Newby, Richard A.; Lippert, Thomas E.

1997-01-01

The gas from combustion or gasification of fossil fuel contains flyash and other particulate. The flyash is separated from the gas in a plurality of standleg moving granular-bed filter modules. Each module includes a dipleg through which the bed media flows into the standleg. The bed media forms a first filter bed having an upper mass having a first frusto-conical surface in a frusto-conical member at the entrance to the standleg and a lower mass having a second frusto-conical surface of substantially greater area than the first surface after it passes through the standleg. A second filter media bed may be formed above the first filter media bed. The gas is fed tangentially into the module above the first surface. The flyash is captured on the first frusto-conical surface and within the bed mass. The processed gas flows out through the second frusto-conical surface and then through the second filter bed, if present. The bed media is cleaned of the captured flyash and recirculated to the moving granular bed filter. Alternatively, the bed media may be composed of the ash from the combustion which is pelletized to form agglomerates. The ash flows through the bed only once; it is not recycled.

Variability of Bed Load Transport During Six Summers of Continuous Measurements in Two Austrian Mountain Streams (Fischbach and Ruetz)

NASA Astrophysics Data System (ADS)

Rickenmann, Dieter

2018-01-01

Previous measurements of bed load transport in gravel bed streams revealed a large temporal and spatial variability of bed load transport rates. Using an impact plate geophone system, continuous bed load transport measurements were made during 6 years in two mountain streams in Austria. The two streams have a snow-melt and glacier-melt dominated hydrologic regime resulting in frequent transport activity during the summer half year. Periods of days to weeks were identified which are associated with approximately constant Shields values that indicate quasi-stable bed conditions. Between these stable periods, the position of the bed load transport function varied while its steepness remained approximately constant. For integration time scales of several hours to 1 day, the fluctuations in bed load transport decreased and the correlation between bed load transport and water discharge increased. For integration times of about 70-100 days, bed load transport is determined by discharge or shear stress to within a factor of about 2, relative to the 6 year mean level. Bed load texture increased with increasing mean flow strength and mean transport intensity. Weak and predominantly clockwise daily hysteresis of bed load transport was found for the first half of the summer period.

[Fire behavior of Mongolian oak leaves fuel-bed under no-wind and zero-slope conditions. I. Factors affecting fire spread rate and modeling].

PubMed

Jin, Sen; Liu, Bo-Fei; Di, Xue-Ying; Chu, Teng-Fei; Zhang, Ji-Li

2012-01-01

Aimed to understand the fire behavior of Mongolian oak leaves fuel-bed under field condition, the leaves of a secondary Mongolian oak forest in Northeast Forestry University experimental forest farm were collected and brought into laboratory to construct fuel-beds with varied loading, height, and moisture content, and a total of 100 experimental fires were burned under no-wind and zero-slope conditions. It was observed that the fire spread rate of the fuel-beds was less than 0.5 m x min(-1). Fuel-bed loading, height, and moisture contents all had significant effects on the fire spread rate. The effect of fuel-bed moisture content on the fire spread had no significant correlations with fuel-bed loading and height, but the effect of fuel-bed height was related to the fuel-bed loading. The packing ratio of fuel-beds had less effect on the fire spread rate. Taking the fuel-bed loading, height, and moisture content as predictive variables, a prediction model for the fire spread rate of Mongolian oak leaves fuel-bed was established, which could explain 83% of the variance of the fire spread rate, with a mean absolute error 0.04 m x min(-1) and a mean relative error less than 17%.

Trends in infant bedding use: National Infant Sleep Position study, 1993-2010.

PubMed

Shapiro-Mendoza, Carrie K; Colson, Eve R; Willinger, Marian; Rybin, Denis V; Camperlengo, Lena; Corwin, Michael J

2015-01-01

Use of potentially hazardous bedding, as defined by the American Academy of Pediatrics (eg, pillows, quilts, comforters, loose bedding), is a modifiable risk factor for sudden infant death syndrome and unintentional sleep-related suffocation. The proportion of US infants sleeping with these types of bedding is unknown. To investigate the US prevalence of and trends in bedding use, we analyzed 1993-2010 data from the National Infant Sleep Position study. Infants reported as being usually placed to sleep with blankets, quilts, pillows, and other similar materials under or covering them in the last 2 weeks were classified as bedding users. Logistic regression was used to describe characteristics associated with bedding use. From 1993 to 2010, bedding use declined but remained a widespread practice (moving average of 85.9% in 1993-1995 to 54.7% in 2008-2010). Prevalence was highest for infants of teen-aged mothers (83.5%) and lowest for infants born at term (55.6%). Bedding use was also frequently reported among infants sleeping in adult beds, on their sides, and on a shared surface. The rate of decline in bedding use was markedly less from 2001-2010 compared with 1993-2000. For 2007 to 2010, the strongest predictors (adjusted odds ratio: ≥1.5) of bedding use were young maternal age, non-white race and ethnicity, and not being college educated. Bedding use for infant sleep remains common despite recommendations against this practice. Understanding trends in bedding use is important for tailoring safe sleep interventions. Copyright © 2015 by the American Academy of Pediatrics.

The bedding of laboratory animals as a source of airborne contaminants.

PubMed

Kaliste, E; Linnainmaa, M; Meklin, T; Torvinen, E; Nevalainen, A

2004-01-01

In work environments with laboratory animals, the bedding of animals binds the excreta as well as other compounds originating from the animals and their environment. These may be generated into the ambient air when the personnel handle bedding in different procedures. This study compares the dustiness of different types of six clean and four soiled beddings from rat or mouse cages. The dust generation of clean bedding varied from <1 to 25 mg/m(3). When used in the cages of rats or mice for 4 days, the dust concentration of the beddings decreased, increased or stayed the same, depending on the type of bedding and animal species. A decrease in dustiness was, however, more common. The levels in the soiled beddings varied from <1 to 8.6 mg/m(3). In the case of the aspen chip bedding, the contents of bedding used in mouse, rat or rabbit cages were analysed for mesophilic bacteria and fungi, mycobacteria and endotoxins. All of these contaminants were variably found in the bedding samples, the maximal concentrations for bacteria were >6 500 000 colony-forming units (cfu)/g, for fungi 212 000 cfu/g, and for endotoxins 6500 ng/g (81 000 EU/g). The results showed that the bedding of laboratory animals may contain biologically effective compounds, and that these may be distributed into the ambient air depending on the characteristics of the bedding material. The dustiness of different bedding types is an important factor affecting the amount and quality of the occupational exposure of the personnel to airborne contaminants.

Trends in Infant Bedding Use: National Infant Sleep Position Study, 1993–2010

PubMed Central

Colson, Eve R.; Willinger, Marian; Rybin, Denis V.; Camperlengo, Lena; Corwin, Michael J.

2015-01-01

BACKGROUND: Use of potentially hazardous bedding, as defined by the American Academy of Pediatrics (eg, pillows, quilts, comforters, loose bedding), is a modifiable risk factor for sudden infant death syndrome and unintentional sleep-related suffocation. The proportion of US infants sleeping with these types of bedding is unknown. METHODS: To investigate the US prevalence of and trends in bedding use, we analyzed 1993–2010 data from the National Infant Sleep Position study. Infants reported as being usually placed to sleep with blankets, quilts, pillows, and other similar materials under or covering them in the last 2 weeks were classified as bedding users. Logistic regression was used to describe characteristics associated with bedding use. RESULTS: From 1993 to 2010, bedding use declined but remained a widespread practice (moving average of 85.9% in 1993–1995 to 54.7% in 2008–2010). Prevalence was highest for infants of teen-aged mothers (83.5%) and lowest for infants born at term (55.6%). Bedding use was also frequently reported among infants sleeping in adult beds, on their sides, and on a shared surface. The rate of decline in bedding use was markedly less from 2001–2010 compared with 1993–2000. For 2007 to 2010, the strongest predictors (adjusted odds ratio: ≥1.5) of bedding use were young maternal age, non-white race and ethnicity, and not being college educated. CONCLUSIONS: Bedding use for infant sleep remains common despite recommendations against this practice. Understanding trends in bedding use is important for tailoring safe sleep interventions. PMID:25452654

Unusual seismogenic soft-sediment deformation structures in Cambrian epicratonic carbonate deposits, western Colorado, U.S.A

NASA Astrophysics Data System (ADS)

Myrow, P.; Chen, J.

2013-12-01

A wide variety of unusual penecontemporaneous deformation structures exist in grainstone and flat-pebble conglomerate beds of the Upper Cambrian strata, western Colorado, including slide scarps, thrusted beds, irregular blocks and internally deformed beds. Slide scarps are characterized by concave-up, sharp surfaces that truncate one or more underlying beds. Thrusted beds record movement of a part of a bed onto itself along a moderate to steeply inclined (generally 25°-40°) ramp. The hanging wall lenses in cases show fault-bend geometries, with either intact or mildly deformed bedding. Irregular bedded to internally deformed blocks isolated on generally flat upper bedding surfaces are similar in composition to the underlying beds. These features represent parts of beds that were detached, moved up onto, and some distances across, the laterally adjacent undisturbed bed surfaces. The blocks moved either at the sediment-water interface or intrastratally at shallow depths within overlying muddy deposits. Finally, internally deformed beds have large blocks, fitted fabrics of highly irregular fragments, and contorted lamination, which represent heterogeneous deformation, such as brecciation and liquefaction. The various deformation structures were most probably triggered by earthquakes, considering the nature of deformation (regional distribution of liquefaction structures, and the brittle segmentation and subsequent transportation of semi-consolidated beds) and the reactivation of Mesoproterozoic, crustal-scale shear zones in the central Rockies during the Late Cambrian. Features produced by initial brittle deformation are unusual relative to most reported seismites, and may represent poorly recognized to unrecognized seismogenic structures in the rock record.

Mark-Release-Recapture Reveals Extensive Movement of Bed Bugs (Cimex lectularius L.) within and between Apartments

PubMed Central

Cooper, Richard; Wang, Changlu; Singh, Narinderpal

2015-01-01

Understanding movement and dispersal of the common bed bug (Cimex lectularius L.) under field conditions is important in the control of infestations and for managing the spread of bed bugs to new locations. We investigated bed bug movement within and between apartments using mark-release-recapture (m-r-r) technique combined with apartment-wide monitoring using pitfall-style interceptors. Bed bugs were collected, marked, and released in six apartments. The distribution of marked and unmarked bed bugs in these apartments and their 24 neighboring units were monitored over 32 days. Extensive movement of marked bed bugs within and between apartments occurred regardless of the number of bed bugs released or presence/absence of a host. Comparison of marked and unmarked bed bug distributions confirms that the extensive bed bug activity observed was not an artifact of the m-r-r technique used. Marked bed bugs were recovered in apartments neighboring five of six m-r-r apartments. Their dispersal rates at 14 or 15 d were 0.0–5.0%. The estimated number of bed bugs per apartment in the six m-r-r apartments was 2,433–14,291 at 4–7 d after release. Longevity of bed bugs in the absence of a host was recorded in a vacant apartment. Marked large nymphs (3rd– 5th instar), adult females, and adult males continued to be recovered up to 57, 113, and 134 d after host absence, respectively. Among the naturally existing unmarked bed bugs, unfed small nymphs (1st– 2nd instar) were recovered up to 134 d; large nymphs and adults were still found at 155 d when the study ended. Our findings provide important insight into the behavioral ecology of bed bugs in infested apartments and have significant implications in regards to eradication programs and managing the spread of bed bugs within multi-occupancy dwellings. PMID:26352145

Hospital-level changes in adult ICU bed supply in the United States

PubMed Central

Wallace, David J.; Seymour, Christopher W.; Kahn, Jeremy M.

2017-01-01

Objective Although the number of intensive care beds in the United States is increasing, little is known about the hospitals responsible for this growth. We sought to better characterize national growth in intensive care beds by identifying hospital-level factors associated with increasing numbers of intensive care beds over time. Design We performed a repeated-measures time series analysis of hospital-level intensive care bed supply using data from Centers for Medicare and Medicaid Services. Setting All United States acute care hospitals with adult intensive care beds over the years 1996 to 2011. Measurements & Main Results We described the number of beds, teaching status, ownership, intensive care occupancy and urbanicity for each hospital in each year of the study. We then examined the relationship between increasing intensive care beds and these characteristics, controlling for other factors. The study included 4,457 hospitals and 55,865 hospital-years. Overall, the majority of intensive care bed growth occurred in teaching hospitals (net +13,471 beds, 72.1% of total growth), hospitals with 250 or more beds (net +18,327 beds, 91.8% of total growth) and hospitals in the highest quartile of occupancy (net +10,157 beds, 54.0% of total growth). In a longitudinal multivariable model, larger hospital size, teaching status, and high intensive care occupancy were associated with subsequent-year growth. Furthermore, the effects of hospital size and teaching status were modified by occupancy: the greatest odds of increasing intensive care unit beds were in hospitals with 500 or more beds in the highest quartile of occupancy (adjusted OR: 18.9; 95% CI: 14.0 – 25.5; p<0.01) and large teaching hospitals in the highest quartile of occupancy (adjusted OR: 7.3; 95% CI: 5.3 – 9.9; p<0.01). Conclusions Increasingly, intensive care bed expansion in the United States is occurring in larger hospitals and teaching centers, particularly following a year with high intensive care unit occupancy. PMID:27661861

75 FR 24572 - Foreign-Trade Zone 29 - Louisville, Kentucky, Application for Subzone, Louisville Bedding Company...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-05

... - Louisville, Kentucky, Application for Subzone, Louisville Bedding Company (Household Bedding Products...-purpose subzone status for the bedding products manufacturing facilities of Louisville Bedding Company..., Louisville; Site 2 - warehouse (4.3 acres) located at 100 Quality Street, Munfordville; and, Site 3...

Evolution of the Structure and Mechanical Strength of a Coal Particle During Combustion in the Atmosphere of Air and the Mixture of Oxygen and Carbon Dioxide / Ewolucja Struktury Oraz Wytrzymałości Mechanicznej Ziarna Węgla Podczas Spalania W Atmosferze Powietrza Oraz Mieszaninie Tlenu I Dwutlenku Węgla

NASA Astrophysics Data System (ADS)

Pełka, Piotr; Golański, Grzegorz; Wieczorek, Paweł

2013-09-01

The research was conducted on the basis of four different types of hard coal and one type of brown coal. There are typical coals commonly used as fuel in Polish CFB boilers. The combustion process was conducted at a temperature of 850°C and the atmosphere of ambient air as well as in the mixture of oxygen and carbon dioxide in different proportions. The research was carried out using specially prepared cubical coal particles with measurements of 15×15mm and also 10×10 mm. The change of the mechanical properties was analyzed based on three parameters, i.e. compression strength, Vickers hardness and fracture toughness. The analysis was supplemented by microscopic images of the surface of the particles using an atomic force microscope. The results obtained clearly indicated the mechanical changes of the coal during its combustion, particularly at the moment of ignition of the char. Moreover, the results correlate very well with the processes of coal comminution that have been described by other authors (Basu, 1999; Chirone et al., 1991) during combustion in the circulating fluidized bed and also explain the sudden change of susceptibility to erosion in the conditions with and without combustion. The measured values can be used as strength parameters in the modelling of the mass loss of coal particles in conditions of circulating fluidized bed combustor that are hard to describe. Badania przeprowadzono na podstawie czterech węgli kamiennych różnego typu oraz jednego węgla brunatnego. Są to typowe węgle energetyczne wykorzystywane powszechnie jako paliwo w kotłach fluidyzacyjnych w Polsce. Proces spalania był prowadzony w temperaturze 850°C w atmosferze powietrza atmosferycznego oraz w atmosferze mieszaniny tlenu oraz dwutlenku węgla w różnych proporcjach. Badania przeprowadzono na spreparowanych do tego celu sześciennych próbkach węgla o wymiarach 15×15 mm oraz 10×10 mm. Zmianę własności mechanicznych przeanalizowano w oparciu o trzy parametry: wytrzymałość na ściskanie, twardości Vickersa oraz współczynnik kruchości. Analizę uzupełniono zdjęciami mikroskopowymi powierzchni ziaren wykonanymi za pomocą mikroskopu sił atomowych. Otrzymane rezultaty wskazują na bardzo wyraźne zmiany wytrzymałościowe węgla podczas jego spalania, szczególnie w chwili zapłonu karbonizatu. Uzyskane wyniki bardzo dobrze korelują z opisywanymi przez innych autorów procesami rozdrabniania węgla (Basu, 1999; Chirone et al., 1991) podczas spalania w warunkach cyrkulacyjnej warstwy fluidalnej. Tłumaczą gwałtowną zmianę podatności na erozję w warunkach bez spalania oraz z towarzyszącym spalaniem. Rezultaty badań mogą posłużyć jako parametry wytrzymałościowe w modelowaniu ubytku masy ziaren węgla w trudnych do opisania warunkach cyrkulacyjnej warstwy fluidalnej.

CO-FIRING COAL, FEEDLOT, AND LITTER BIOMASS (CFB AND LFB) FUELS IN PULVERIZED FUEL AND FIXED BED BURNERS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kalyan Annamalai; John Sweeten; Saqib Mukhtar

2002-01-15

Intensive animal feeding operations create large amounts of animal waste that must be safely disposed of in order to avoid environmental degradation. Cattle feedlots and chicken houses are two examples. In feedlots, cattle are confined to small pens and fed a high calorie grain diet in preparation for slaughter. In chicken houses, thousands of chickens are kept in close proximity. In both of these operations, millions of tons of manure are produced every year. In this project a co-firing technology is proposed which would use manure that cannot be used for fertilizer, for power generation. Since the animal manure hasmore » economic uses as both a fertilizer and as a fuel, it is properly referred to as feedlot biomass (FB) for cow manure, or litter biomass (LB) for chicken manure. The biomass will be used a as a fuel by mixing it with coal in a 90:10 blend and firing it in existing coal fired combustion devices. This technique is known as co-firing, and the high temperatures produced by the coal will allow the biomass to be completely combusted. Therefore, it is the goal of the current research to develop an animal biomass cofiring technology. A cofiring technology is being developed by performing: (1) studies on fundamental fuel characteristics, (2) small scale boiler burner experiments, (3) gasifier experiments, (4) computer simulations, and (5) an economic analysis. The fundamental fuel studies reveal that biomass is not as high a quality fuel as coal. The biomass fuels are higher in ash, higher in moisture, higher in nitrogen and sulfur (which can cause air pollution), and lower in heat content than coal. Additionally, experiments indicate that the biomass fuels have higher gas content, release gases more readily than coal, and less homogeneous. Small-scale boiler experiments revealed that the biomass blends can be successfully fired, and NO{sub x} pollutant emissions produced will be similar to or lower than pollutant emissions when firing coal. This is a surprising result as the levels of N are higher in the biomass fuel than in coal. Further experiments showed that biomass is twice or more effective than coal when used in a reburning process to reduce NO{sub x} emissions. Since crushing costs of biomass fuels may be prohibitive, stoker firing may be cost effective; in order simulate such a firing, future work will investigate the performance of a gasifier when fired with larger sized coal and biomass. It will be a fixed bed gasifier, and will evaluate blends, coal, and biomass. Computer simulations were performed using the PCGC-2 code supplied by BYU and modified by A&M with three mixture fractions for handling animal based biomass fuels in order to include an improved moisture model for handling wet fuels and phosphorus oxidation. Finally the results of the economic analysis show that considerable savings can be achieved with the use of biomass. In the case of higher ash and moisture biomass, the fuel cost savings will be reduced, due to increased transportation costs. A spreadsheet program was created to analyze the fuel savings for a variety of different moisture levels, ash levels, and power plant operating parameters.« less

75 FR 28554 - Foreign-Trade Zone 50 Long Beach, California, Application for Subzone, Louisville Bedding Company...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-21

..., California, Application for Subzone, Louisville Bedding Company (Household Bedding Products), Ontario... Avenue in Ontario, California. The facility is used to manufacture household bedding products, including... shipments for the domestic market, the finished household bedding products would be entered for consumption...

21 CFR 892.1350 - Nuclear scanning bed.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Nuclear scanning bed. 892.1350 Section 892.1350...) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1350 Nuclear scanning bed. (a) Identification. A nuclear scanning bed is an adjustable bed intended to support a patient during a nuclear medicine...

21 CFR 892.1350 - Nuclear scanning bed.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Nuclear scanning bed. 892.1350 Section 892.1350...) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1350 Nuclear scanning bed. (a) Identification. A nuclear scanning bed is an adjustable bed intended to support a patient during a nuclear medicine...

21 CFR 892.1350 - Nuclear scanning bed.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Nuclear scanning bed. 892.1350 Section 892.1350...) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1350 Nuclear scanning bed. (a) Identification. A nuclear scanning bed is an adjustable bed intended to support a patient during a nuclear medicine...

21 CFR 892.1350 - Nuclear scanning bed.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Nuclear scanning bed. 892.1350 Section 892.1350...) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1350 Nuclear scanning bed. (a) Identification. A nuclear scanning bed is an adjustable bed intended to support a patient during a nuclear medicine...

21 CFR 892.1350 - Nuclear scanning bed.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Nuclear scanning bed. 892.1350 Section 892.1350...) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1350 Nuclear scanning bed. (a) Identification. A nuclear scanning bed is an adjustable bed intended to support a patient during a nuclear medicine...

3-D capacitance density imaging of fluidized bed

DOEpatents

Fasching, George E.

1990-01-01

A three-dimensional capacitance density imaging of a gasified bed or the like in a containment vessel is achieved using a plurality of electrodes provided circumferentially about the bed in levels and along the bed in channels. The electrodes are individually and selectively excited electrically at each level to produce a plurality of current flux field patterns generated in the bed at each level. The current flux field patterns are suitably sensed and a density pattern of the bed at each level determined. By combining the determined density patterns at each level, a three-dimensional density image of the bed is achieved.

Correlation of Paleocene Harmon and Hansen lignite beds, Adams, Billings, Bowman, Golden Valley, Hettinger, and Slope Counties, Williston Basin, North Dakota

DOE Office of Scientific and Technical Information (OSTI.GOV)

Keighin, C.W.; Flores, R.M.; Ochs, A.

In southwestern North Dakota, minable lignite beds in the Paleocene Fort Union Formation include the Harmon and Hansen beds in the Bowman-Gascoyne area. Data from more than 700 drill holes penetrating these beds was used to construct stratigraphic cross sections. The Harmon and Hansen beds are the thickest and most laterally persistent lignites found under < 150 ft of overburden. The Harmon coal bed is as much as 34 ft thick, and is often split by claystone interbeds of variable thickness. The Hansen coal bed typically occurs 10--100 ft below the Harmon coal bed; it rarely attains a thickness ofmore » 15 ft, and averages 4 ft in thickness.« less

Effect of bed characters on the direct synthesis of dimethyldichlorosilane in fluidized bed reactor.

PubMed

Zhang, Pan; Duan, Ji H; Chen, Guang H; Wang, Wei W

2015-03-06

This paper presents the numerical investigation of the effects of the general bed characteristics such as superficial gas velocities, bed temperature, bed heights and particle size, on the direct synthesis in a 3D fluidized bed reactor. A 3D model for the gas flow, heat transfer, and mass transfer was coupled to the direct synthesis reaction mechanism verified in the literature. The model was verified by comparing the simulated reaction rate and dimethyldichlorosilane (M2) selectivity with the experimental data in the open literature and real production data. Computed results indicate that superficial gas velocities, bed temperature, bed heights, and particle size have vital effect on the reaction rates and/or M2 selectivity.

Effect of Bed Characters on the Direct Synthesis of Dimethyldichlorosilane in Fluidized Bed Reactor

PubMed Central

Zhang, Pan; Duan, Ji H.; Chen, Guang H.; Wang, Wei W.

2015-01-01

This paper presents the numerical investigation of the effects of the general bed characteristics such as superficial gas velocities, bed temperature, bed heights and particle size, on the direct synthesis in a 3D fluidized bed reactor. A 3D model for the gas flow, heat transfer, and mass transfer was coupled to the direct synthesis reaction mechanism verified in the literature. The model was verified by comparing the simulated reaction rate and dimethyldichlorosilane (M2) selectivity with the experimental data in the open literature and real production data. Computed results indicate that superficial gas velocities, bed temperature, bed heights, and particle size have vital effect on the reaction rates and/or M2 selectivity. PMID:25742729

Bed Bugs (Cimex lectularius) as Vectors of Trypanosoma cruzi

PubMed Central

Salazar, Renzo; Castillo-Neyra, Ricardo; Tustin, Aaron W.; Borrini-Mayorí, Katty; Náquira, César; Levy, Michael Z.

2015-01-01

Populations of the common bed bug, Cimex lectularius, have recently undergone explosive growth. Bed bugs share many important traits with triatomine insects, but it remains unclear whether these similarities include the ability to transmit Trypanosoma cruzi, the etiologic agent of Chagas disease. Here, we show efficient and bidirectional transmission of T. cruzi between hosts and bed bugs in a laboratory environment. Most bed bugs that fed on experimentally infected mice acquired the parasite. A majority of previously uninfected mice became infected after a period of cohabitation with exposed bed bugs. T. cruzi was also transmitted to mice after the feces of infected bed bugs were applied directly to broken host skin. Quantitative bed bug defecation measures were similar to those of important triatomine vectors. Our findings suggest that the common bed bug may be a competent vector of T. cruzi and could pose a risk for vector-borne transmission of Chagas disease. PMID:25404068

Bed bugs, public health, and social justice: Part 2, An opinion survey.

PubMed

Eddy, Christopher; Jones, Susan C

2011-04-01

Bed bug infestations have resurged globally, nationally, and locally, yet the public health community in the U.S. has yet to mount a coordinated response to the escalating bed bug problem. Surveys of attendees at the 2009 National Environmental Health Association Annual Educational Conference & Exhibition, 2009 Ohio Association of Health Commissioners Fall Conference, 2009 Central Ohio Bed Bug Summit, and 2010 Hamilton County Council on Aging Annual Conference were conducted to gauge opinions about bed bugs. Survey results revealed that 90% of all respondents considered bed bugs to be a public health concern, and 73% indicated that bed bugs pose an environmental justice concern. These findings, which indicate that bed bugs are an inescapable public health mandate with environmental justice undertones, should rally public health agencies at federal, state, and local levels to respond with authority of agency to the escalating bed bug problem.

Relationship between fluid bed aerosol generator operation and the aerosol produced

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carpenter, R.L.; Yerkes, K.

1980-12-01

The relationships between bed operation in a fluid bed aerosol generator and aerosol output were studied. A two-inch diameter fluid bed aerosol generator (FBG) was constructed using stainless steel powder as a fluidizing medium. Fly ash from coal combustion was aerosolized and the influence of FBG operating parameters on aerosol mass median aerodynamic diameter (MMAD), geometric standard deviation (sigma/sub g/) and concentration was examined. In an effort to extend observations on large fluid beds to small beds using fine bed particles, minimum fluidizing velocities and elutriation constant were computed. Although FBG minimum fluidizing velocity agreed well with calculations, FBG elutriationmore » constant did not. The results of this study show that the properties of aerosols produced by a FBG depend on fluid bed height and air flow through the bed after the minimum fluidizing velocity is exceeded.« less

Differences in sleep complaints in adults with varying levels of bed days residing in extended care facilities for chronic disease management.

PubMed

Fox, Mary T; Sidani, Souraya; Brooks, Dina

2010-05-01

This cohort study examined differences in perceived insomnia and daytime sleepiness in 67 adults residing in extended care facilities for chronic disease management who had varying levels of bed days. One bed day was defined as spending 24 hours in bed. Planned pairwise comparisons, using Bonferroni adjustment, were made between participants who spent 0 (n = 21), 2 to 4 (n = 23), and 5 to 7 (n = 23) days in bed during 1 week of monitoring. Participants who spent 5 to 7 days in bed had significantly greater insomnia than those who spent 2 to 4 days in bed. No group differences were found in daytime sleepiness. Based on the findings, nurses may assess subjective insomnia and explore sleep hygiene strategies, such as increasing time out of bed with patients who have high levels of 5 to 7 bed days.

Ethnic differences in prevalence and determinants of mother-child bed-sharing in early childhood.

PubMed

Luijk, Maartje P C M; Mileva-Seitz, Viara R; Jansen, Pauline W; van IJzendoorn, Marinus H; Jaddoe, Vincent W V; Raat, Hein; Hofman, Albert; Verhulst, Frank C; Tiemeier, Henning

2013-11-01

To date few studies have examined how multiple layers of influences shape the emergence of bed-sharing practices in the first 2 years postpartum. In our report, we examined bed-sharing in a large multiethnic sample, exploring the influences of three broad classes of influence on bed-sharing at single time points and across time: (1) sociodemographic and (2) contextual factors such as breastfeeding, maternal mental health and stress, and (3) child temperament and sleep habits. Frequencies of bed-sharing were assessed at two time points, 2 and 24 months, in a population-based multiethnic (Dutch, Turkish or Moroccan, and Caribbean) sample of 6309 children born in the Netherlands. In Dutch mothers, the majority of mothers did not share their beds with their child, and bed-sharing rates decreased from 2 to 24 months. Other ethnic groups showed higher bed-sharing rates, typified by both increases in bed-sharing (the Turkish and Moroccan group) and persistence of bed-sharing over time (the Caribbean group). There were few family and child characteristics associated with bed-sharing in the non-Dutch ethnic groups. In contrast, bed-sharing in Dutch mothers was associated with child temperament and sleeping problems, maternal depression, and sociodemographic variables like crowding and maternal education. Our results suggest that mothers with a Turkish and Moroccan or Caribbean background were more influenced by cultural values, whereas bed-sharing practices were more reactive in the Dutch group. Copyright © 2013 Elsevier B.V. All rights reserved.

Clinical phenotype of bipolar disorder with comorbid binge eating disorder

PubMed Central

McElroy, Susan L.; Crow, Scott; Biernacka, Joanna M.; Winham, Stacey; Geske, Jennifer; Cuellar Barboza, Alfredo B.; Prieto, Miguel L.; Chauhan, Mohit; Seymour, Lisa R.; Mori, Nicole; Frye, Mark A.

2017-01-01

Background To explore the relationship between binge eating disorder (BED) and obesity in patients with bipolar disorder (BP). Methods 717 patients participating in the Mayo Clinic Bipolar Biobank completed structured diagnostic interviews and questionnaires for demographic and illness-related variables. They also had weight and height measured to determine body mass index (BMI). The effects of BED and obesity (BMI≥30 kg/m2), as well as their interaction, were assessed on one measure of general medical burden and six proxies of psychiatric illness burden. Results 9.5% of patients received a clinical diagnosis of BED and 42.8% were obese. BED was associated with a significantly elevated BMI. Both BED and obesity were associated with greater psychiatric and general illness burden, but illness burden profiles differed. After controlling for obesity, BED was associated with suicidality, psychosis, mood instability, anxiety disorder comorbidity, and substance abuse comorbidity. After controlling for BED status, obesity was associated with greater general medical comorbidity, but lower substance abuse comorbidity. There were no significant interaction effects between obesity and BED, or BMI and BED, on any illness burden outcome. Limitations There may have been insufficient power to detect interactions between BED and obesity. Conclusions: Among patients with BP, BED and obesity are highly prevalent and correlated, but associated with different profiles of enhanced illness burden. As the association of BED with greater psychiatric illness burden remained significant even after accounting for the effect of obesity, BP with BED may represent a clinically important sub-phenotype. PMID:23742827

Debris-bed friction of hard-bedded glaciers

USGS Publications Warehouse

Cohen, D.; Iverson, N.R.; Hooyer, T.S.; Fischer, U.H.; Jackson, M.; Moore, P.L.

2005-01-01

[1] Field measurements of debris-bed friction on a smooth rock tablet at the bed of Engabreen, a hard-bedded, temperate glacier in northern Norway, indicated that basal ice containing 10% debris by volume exerted local shear traction of up to 500 kPa. The corresponding bulk friction coefficient between the dirty basal ice and the tablet was between 0.05 and 0.08. A model of friction in which nonrotating spherical rock particles are held in frictional contact with the bed by bed-normal ice flow can account for these measurements if the power law exponent for ice flowing past large clasts is 1. A small exponent (n < 2) is likely because stresses in ice are small and flow is transient. Numerical calculations of the bed-normal drag force on a sphere in contact with a flat bed using n = 1 show that this force can reach values several hundred times that on a sphere isolated from the bed, thus drastically increasing frictional resistance. Various estimates of basal friction are obtained from this model. For example, the shear traction at the bed of a glacier sliding at 20 m a-1 with a geothermally induced melt rate of 0.006 m a-1 and an effective pressure of 300 kPa can exceed 100 kPa. Debris-bed friction can therefore be a major component of sliding resistance, contradicting the common assumption that debris-bed friction is negligible. Copyright 2005 by the American Geophysical Union.

Relationship Between Faults Oriented Parallel and Oblique to Bedding in Neogene Massive Siliceous Mudstones at The Horonobe Underground Research Laboratory, Japan

NASA Astrophysics Data System (ADS)

Hayano, Akira; Ishii, Eiichi

2016-10-01

This study investigates the mechanical relationship between bedding-parallel and bedding-oblique faults in a Neogene massive siliceous mudstone at the site of the Horonobe Underground Research Laboratory (URL) in Hokkaido, Japan, on the basis of observations of drill-core recovered from pilot boreholes and fracture mapping on shaft and gallery walls. Four bedding-parallel faults with visible fault gouge, named respectively the MM Fault, the Last MM Fault, the S1 Fault, and the S2 Fault (stratigraphically, from the highest to the lowest), were observed in two pilot boreholes (PB-V01 and SAB-1). The distribution of the bedding-parallel faults at 350 m depth in the Horonobe URL indicates that these faults are spread over at least several tens of meters in parallel along a bedding plane. The observation that the bedding-oblique fault displaces the Last MM fault is consistent with the previous interpretation that the bedding- oblique faults formed after the bedding-parallel faults. In addition, the bedding-parallel faults terminate near the MM and S1 faults, indicating that the bedding-parallel faults with visible fault gouge act to terminate the propagation of younger bedding-oblique faults. In particular, the MM and S1 faults, which have a relatively thick fault gouge, appear to have had a stronger control on the propagation of bedding-oblique faults than did the Last MM fault, which has a relatively thin fault gouge.

Reported bed net ownership and use in social contacts is associated with uptake of bed nets for malaria prevention in pregnant women in Ghana.

PubMed

Ernst, Kacey C; Erly, Steven; Adusei, Charity; Bell, Melanie L; Kessie, David Komla; Biritwum-Nyarko, Alberta; Ehiri, John

2017-01-04

Despite progress made in the last decades, malaria persists as a pressing health issue in sub-Saharan Africa. Pregnant women are particularly vulnerable to infection and serious health outcomes for themselves and their unborn child. Risk can be mitigated through appropriate use of control measures such as insecticide-treated bed nets. Although social networks can influence uptake of preventive strategies, the role of social influence on bed net ownership has not been explored. During an evaluation of a bed net distribution programme, the influence of non-health care advisors on ownership and use of bed nets by pregnant women in Kumasi, Ghana was examined. Data were collected through in-person interviews with 300 pregnant women seeking antenatal care in an urban hospital in Kumasi, Ghana. Participants were asked about their bed net ownership, bed net use, and information about three personal contacts that they go to for pregnancy advice. Information about these advisors was combined into an influence score. Logistic regression models were used to determine the association between the score and bed net ownership. Those who owned a bed net were further assessed to determine if interpersonal influence was associated with self-reported sleeping under the bed net the previous night. Of the 294 women in the analysis, 229 (78%) reported owning bed nets. Of these bed net owners, 139 (61%) reported using a bed net the previous night. A dose response relationship was observed between the interpersonal influence score and bed net ownership and use. Compared to the lowest influence score, those with the highest influence score (>1 SD above the mean) were marginally more likely to own a bed net [OR = 2.37, 95% CI (0.87, 6.39)] and much more likely to use their bed net [5.38, 95% CI (1.89, 15.25)] after adjusting for other factors. Interpersonal influence appears to have modest impact on ownership and use of bed nets by pregnant women in an urban area of Ghana. Further investigations would need to be conducted to determine if the relationship is causal or if individuals who associate are simply more likely to have similar practices.

Infant's bed climate and bedding in the Japanese home.

PubMed

Nakamura Ikeda, Rie; Fukai, Kiyoko; Okamoto Mizuno, Kazue

2012-06-01

to assess the bed climate of infants in their homes in Japan. descriptive, exploratory, non-experimental research design. the data were collected at the participants' homes under normal circumstances. nineteen healthy infants between the ages of two and five months. Their mothers, who joined a parenting class organised by a maternity clinic in Okayama, Japan, consented to participate in this study. we visited the infants' homes and interviewed their mothers concerning the types and use of bedding. The temperature and relative humidity of the bed climate at the back and foot of the bedding, and in the room were measured every minute for four consecutive days. Differences among the bed climates measured during three seasons (spring, summer, and autumn) were assessed by one-way analysis of variance. The bed temperature was higher for infants than for adults. No significant difference in temperature was noted among the three seasons. The bed temperature was about 36.0°C when waterproof sheets and futon mattresses for children or adult were used. The average relative humidity of the bed climate at the back was highest in summer, followed by that in spring and autumn; the differences were significant. The use of waterproof sheets and futon mattresses for children in summer increased the relative humidity to 80% or more. The use of infant beds, sunoko drainboards, and cotton futon mattresses in summer was effective in reducing the bed humidity. these results suggest that nurse-midwives should advise the parents on comfortable bed climates for their infants, as well as how to select and use bedding for them. Copyright © 2010 Elsevier Ltd. All rights reserved.

Repellency of selected chemicals against the bed bug (Hemiptera: Cimicidae).

PubMed

Wang, Changlu; Lü, Lihua; Zhang, Aijun; Liu, Chaofeng

2013-12-01

In recent years, the common bed bug, Cimex lectularius L. (Hemiptera: Cimicidae), became a major public health concern in urban communities. Bed bugs are notoriously difficult to control, and their bites are not tolerated by most people. The public has an urgent need for materials and methods to reduce bed bug introduction and bites during work, travel, or sleep. A repellent product will help achieve these goals by discouraging and preventing bed bugs from moving to a protected area. We evaluated the repellency of three commercially available insect repellent or control materials and five nonregistered materials with the goal of identifying safe and effective bed bug repellents. The two commercial repellent products that contained 7% picaridin or 0.5% permethrin had little repellency against bed bugs. N,N-diethyl-m-toluamide (DEET), the most commonly used insect repellent, provided a high level of repellency against bed bugs. When a host cue (carbon dioxide) was present, the minimum DEET concentration to repel > or = 94% of the bed bugs for a9-h period was 10%. The longevity of repellency of DEET was concentration dependent. At 25% concentration, DEET-treated fabric surface remained highly repellent to bed bugs for a 14-d period. However, DEET has a strong smell and dissolves certain plastic materials. Therefore, we evaluated several odorless, noncorrosive, and potentially effective repellents. Isolongifolenone and isolongifolanone, two natural products and recently reported insect repellents, exhibited strong repellent property against bed bugs but at significantly lower levels than DEET. Three novel potential repellent compounds discovered by Bedoukian Research Inc. (Danbury, CT) exhibited similar level of repellency and longevity as DEET for repelling bed bugs. These nonirritant and odorless compounds are promising candidates as alternatives to DEET for reducing the spread of bed bugs and bed bug bites.

The Effects of Long Duration Bed Rest on Functional Mobility and Balance: Relationship to Resting State Motor Cortex Connectivity

NASA Technical Reports Server (NTRS)

Erdeniz, B.; Koppelmans, V.; Bloomberg, J. J.; Kofman, I. S.; DeDios, Y. E.; Riascos-Castaneda, R. F.; Wood, S. J.; Mulavara, A. P.; Seidler, R. D.

2014-01-01

NASA offers researchers from a variety of backgrounds the opportunity to study bed rest as an experimental analog for space flight. Extended exposure to a head-down tilt position during long duration bed rest can resemble many of the effects of a low-gravity environment such as reduced sensory inputs, body unloading and increased cephalic fluid distribution. The aim of our study is to a) identify changes in brain function that occur with prolonged bed rest and characterize their recovery time course; b) assess whether and how these changes impact behavioral and neurocognitive performance. Thus far, we completed data collection from six participants that include task based and resting state fMRI. The data have been acquired through the bed rest facility located at the University of Texas Medical Branch (Galveston, TX). Subjects remained in bed with their heads tilted down 6 degrees below their feet for 70 consecutive days. Behavioral measures and neuroimaging assessments were obtained at seven time points: a) 7 and 12 days before bed rest; b) 7, 30, and 65 days during bed rest; and c) 7 and 12 days after bed rest. Functional connectivity magnetic resonance imaging (FcMRI) analysis was performed to assess the connectivity of motor cortex in and out of bed rest. We found a decrease in motor cortex connectivity with vestibular cortex and the cerebellum from pre bed rest to in bed rest. We also used a battery of behavioral measures including the functional mobility test and computerized dynamic posturography collected before and after bed rest. We will report the preliminary results of analyses relating brain and behavior changes. Furthermore, we will also report the preliminary results of a spatial working memory task and vestibular stimulation during in and out of bed rest.

Characterization of Binge-Eating Behavior in Individuals With Binge-Eating Disorder in an Adult Population in the United States.

PubMed

Pawaskar, Manjiri; Solo, Kirk; Valant, Jason; Schmitt, Emily; Nwankwo, Millicent; Herman, Barry K

2016-10-27

Characterize the frequency, duration, and severity of binge-eating behaviors in adults meeting DSM-5 criteria for binge-eating disorder (BED) in a large US community sample. A representative sample of US adults from the National Health and Wellness Survey was recruited from an online panel and asked to respond to an Internet survey (conducted in October 2013) that included questions designed to assess binge-eating behaviors in relation to DSM-5 BED diagnostic criteria. Of 22,397 respondents, 344 self-reported meeting DSM-5 BED criteria (BED respondents). Most BED respondents reported that binge-eating episodes had occurred for the past 7-12 months (61.0%), and 93.6% reported ≥ 2-3 binge-eating episodes/wk. All BED respondents reported that "extreme" (52.6%) or "great" (47.4%) distress levels were associated with binge-eating episodes. Among BED respondents who agreed to provide detailed binge-eating behavior data after being invited to respond to additional survey questions, 40.6% reported binge eating on average > 1 time/d, and 59.2% reported binge eating 2-3 times/d. For 44.5% of BED respondents, binge-eating duration was 31-60 minutes. BED respondents reported that they "very often" (36.6%) or "often" (34.0%) had urges to binge eat between 7-10 pm. "Feeling disgusted with oneself, depressed, or guilty afterward" was the most bothersome symptom of binge eating for BED respondents (extremely bothersome: 41.9%). Binge-eating frequency among BED respondents averaged once daily. Most BED respondents exhibited binge-eating behavior for 7-12 months, often with severe symptoms. These findings highlight the disease burden of BED and have potential implications for diagnosing and treating BED. © Copyright 2016 Physicians Postgraduate Press, Inc.

Ammonia, Total Reduced Sulfides, and Greenhouse Gases of Pine Chip and Corn Stover Bedding Packs.

PubMed

Spiehs, Mindy J; Brown-Brandl, Tami M; Parker, David B; Miller, Daniel N; Berry, Elaine D; Wells, James E

2016-03-01

Bedding materials may affect air quality in livestock facilities. Our objective in this study was to compare headspace concentrations of ammonia (NH), total reduced sulfides (TRS), carbon dioxide (CO), methane (CH), and nitrous oxide (NO) when pine wood chips ( spp.) and corn stover ( L.) were mixed in various ratios (0, 10, 20, 30, 40, 60, 80, and 100% pine chips) and used as bedding with manure. Air samples were collected from the headspace of laboratory-scaled bedded manure packs weekly for 42 d. Ammonia concentrations were highest for bedded packs containing 0, 10, and 20% pine chips (equivalent to 501.7, 502.3, and 502.3 mg m, respectively) in the bedding mixture and were lowest when at least 80% pine chips were used as bedding (447.3 and 431.0 mg m, respectively for 80 and 100% pine chip bedding). The highest NH concentrations were observed at Day 28. The highest concentration of TRS was observed when 100% pine chips were used as bedding (11.4 µg m), with high concentrations occurring between Days 7 and 14, and again at Day 35. Greenhouse gases were largely unaffected by bedding material but CH and CO concentrations increased as the bedded packs aged and NO concentrations were highly variable throughout the incubation. We conclude that a mixture of bedding material that contains 30 to 40% pine chips may be the ideal combination to reduce both NH and TRS emissions. All gas concentrations increased as the bedded packs aged, suggesting that frequent cleaning of facilities would improve air quality in the barn, regardless of bedding materials used. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Material exchange and food web of seagrass beds in the Sylt-Rømø Bight: how significant are community changes at the ecosystem level?

NASA Astrophysics Data System (ADS)

Asmus, H.; Asmus, R.

2000-07-01

Material exchange, biodiversity and trophic transfer within the food web were investigated in two different types of intertidal seagrass beds: a sheltered, dense Zostera marina bed and a more exposed, sparse Z. noltii bed, in the Northern Wadden Sea. Both types of Zostera beds show a seasonal development of above-ground biomass, and therefore measurements were carried out during the vegetation period in summer. The exchange of particles and nutrients between seagrass beds and the overlying water was measured directly using an in situ flume. Particle sedimentation [carbon (C), nitrogen (N) and phosphorus (P) constituents] from the water column prevailed in dense seagrass beds. In the sheltered, dense seagrass bed, a net particle uptake was found even on windy days (7-8 Beaufort). Dissolved inorganic N and orthophosphate were mainly taken up by the dense seagrass bed. At times of strong winds, nutrients were released from the benthic community to tidal waters. In a budget calculation of total N and total P, the dense seagrass beds were characterised as a material sink. The seagrass beds with sparse Z. noltii were a source of particles even during calm weather. The uptake of dissolved inorganic N in the sparse seagrass bed was low but significant, while the uptake of inorganic phosphate and silicate by seagrasses and their epiphytes was exceeded by release processes from the sediment into the overlying water. Estimates at the ecosystem level showed that material fluxes of seagrass beds in the Sylt-Rømø Bight are dominated by the dense type of Zostera beds. Therefore, seagrass beds act as a sink for particles and for dissolved inorganic nutrients. During storms, seagrass beds are distinct sources for inorganic nutrients. The total intertidal area of the Sylt-Rømø Bight could be described as a sink for particles and a source for dissolved nutrients. This balance of the material budget was estimated by either including or excluding seagrass beds. Including the subtidal part, the function of the ecosystem as a source for particles increased, supposing that all seagrass beds were lost from the area. During the vegetation period, seagrass beds act as a storage compartment for material accumulated in the living biomass of the community. There was great biodiversity among the plant and animal groups found in intertidal seagrass beds of the Sylt-Rømø Bay, representing 50-86% of the total number of species investigated, depending on the particular group. Since most species are not exclusively seagrass residents, the loss of intertidal seagrass beds would be of minor importance for biodiversity at the ecosystem level. Food web structure in seagrass beds is different from other intertidal communities. Primary production and detritus input is high, but secondary production is similar to that of unvegetated areas, although the relative importance of the trophic guilds is different. The loss of seagrass beds leads to profound alterations in the food web of the total ecosystem. Historical as well as recent changes in material fluxes and energy flow due to man-made alterations to the ecosystem are discussed.

7 CFR 2902.15 - Bedding, bed linens, and towels.

Code of Federal Regulations, 2010 CFR

2010-01-01

... PROCUREMENT Designated Items § 2902.15 Bedding, bed linens, and towels. (a) Definition. (1) Bedding is that... minimum biobased content is 12 percent and shall be based on the amount of qualifying biobased carbon in..., and silk are not qualifying biobased feedstocks for the purpose of determining the biobased content of...

Health Information in Amharic (Amarɨñña / አማርኛ )

MedlinePlus

... Section Bed Bugs Bed Bug Control in Residences - English PDF Bed Bug Control in Residences - Amarɨñña / አማርኛ ( ... Department of Agriculture Vacuuming to Capture Bed Bugs - English PDF Vacuuming to Capture Bed Bugs - Amarɨñña / አማርኛ ( ...

Thermal Analysis of Fluidized Bed and Fixed Bed Latent Heat Thermal Storage System

NASA Astrophysics Data System (ADS)

Beemkumar, N.; Karthikeyan, A.; Shiva Keshava Reddy, Kota; Rajesh, Kona; Anderson, A.

2017-05-01

Thermal energy storage technology is essential because its stores available energy at low cost. Objective of the work is to store the thermal energy in a most efficient method. This work is deal with thermal analysis of fluidized bed and fixed bed latent heat thermal storage (LHTS) system with different encapsulation materials (aluminium, brass and copper). D-Mannitol has been used as phase change material (PCM). Encapsulation material which is in orbicular shape with 4 inch diameter and 2 mm thickness orbicular shaped product is used. Therminol-66 is used as a heat transfer fluid (HTF). Arrangement of encapsulation material is done in two ways namely fluidized bed and fixed bed thermal storage system. Comparison was made between the performance of fixed bed and fluidized bed with different encapsulation material. It is observed that from the economical point of view aluminium in fluidized bed LHTS System has highest efficiency than copper and brass. The thermal energy storage system can be analyzed with fixed bed by varying mass flow rate of oil paves a way to find effective heat energy transfer.

Flow resistance and suspended load in sand-bed rivers: Simplified stratification model

USGS Publications Warehouse

Wright, S.; Parker, G.

2004-01-01

New methods are presented for the prediction of the flow depth, grain-size specific near-bed concentration, and bed-material suspended sediment transport rate in sand-bed rivers. The salient improvements delineated here all relate to the need to modify existing formulations in order to encompass the full range of sand-bed rivers, and in particular large, low-slope sand-bed rivers. They can be summarized as follows: (1) the inclusion of density stratification effects in a simplified manner, which have been shown in the companion paper to be particularly relevant for large, low-slope, sand-bed rivers; (2) a new predictor for near-bed entrainment rate into suspension which extends a previous relation to the range of large, low-slope sand-bed rivers; and (3) a new predictor for form drag which again extends a previous relation to include large, low-slope sand-bed rivers. Finally, every attempt has been made to cast the relations in the simplest form possible, including the development of software, so that practicing engineers may easily use the methods. ?? ASCE.

Survival and Transstadial Persistence of Trypanosoma cruzi in the bed bug (Hemiptera: Cimicidae).

PubMed

Blakely, Brittny N; Hanson, Stephen F; Romero, Alvaro

2018-05-04

Bed bug populations are increasing around the world at an alarming rate and have become a major public health concern. The appearance of bed bug populations in areas where Chagas disease is endemic raises questions about the role of these insects in the transmission of Trypanosoma cruzi, the etiological agent of the disease. In a series of laboratory evaluations, bed bug adults and nymphs were experimentally fed with T. cruzi-infected blood to assess the ability of T. cruzi to survive inside the bed bug and throughout the insect's molting process. Live T. cruzi were observed in gut contents of experimentally infected bed bug adults via light microscopy and the identity of the parasite was confirmed via polymerase chain reaction analysis. T. cruzi persisted at least 97-d postinfection in adult bed bugs. Nymphal stage bed bugs that were infected with T. cruzi maintained the parasite after molting, indicating that transstadial passage of T. cruzi in bed bugs took place. This report provides further evidence of acquisition, maintenance, and for the first time, transstadial persistence of T. cruzi in bed bugs.

Reducing Respiratory Health Risks to Horses and Workers: A Comparison of Two Stall Bedding Materials

PubMed Central

Saastamoinen, Markku; Särkijärvi, Susanna; Hyyppä, Seppo

2015-01-01

Simple Summary In this study, the effect of wood shavings and peat was examined on stable air quality and health of horses and stable workers. The ammonia level in the boxes in which peat was used as bedding was non-existent or very low. The respiratory symptoms in horses increased regardless of the bedding material at the beginning of the study. The health status of the horses on peat bedding returned to the initial level in the end of the trial but horses in stalls bedded with wood shavings continued to be symptomatic. The hooves of the horses in stalls with peat bedding had a better moisture content. The results suggest that peat is a better bedding material for horses and people working or visiting horse stables than wood shavings. Abstract Stable air quality and the choice of bedding material are an important health issue both in horses and people working or visiting horse stables. Risks of impaired respiratory health are those that can especially be avoided by improving air quality in the stable. The choice of bedding material is particularly important in cold climate conditions; where horses are kept most of the day and year indoors throughout their life. This study examined the effect of two bedding materials; wood shavings and peat; on stable air quality and health of horses. Ammonia and dust levels were also measured to assess conditions in the stable. Ammonia was not detected or was at very low levels (<0.25 ppm) in the boxes in which peat was used as bedding; but its concentration was clearly higher (1.5–7.0 ppm) in stalls with wood shavings as bedding. Personal measurements of workers revealed quite high ammonia exposure (5.9 ppm8h) in the boxes in which wood shavings were used; but no exposure was observed in stalls bedded with peat. The respiratory symptoms in horses increased regardless of the bedding material at the beginning of the study. The health status of the horses in the peat bedding group returned to the initial level in the end of the trial but horses bedded with wood shavings continued to be symptomatic. The hooves of the horses with peat bedding had a better moisture content than those of the horses bedded with wood shavings. The results suggest that peat is a better bedding material for horses than wood shavings regarding the health of both horses and stable workers. PMID:26479479

Bed Bug Infestations in an Urban Environment

PubMed Central

Svoboda, Tomislav J.; De Jong, Iain J.; Kabasele, Karl J.; Gogosis, Evie

2005-01-01

Until recently, bed bugs have been considered uncommon in the industrialized world. This study determined the extent of reemerging bed bug infestations in homeless shelters and other locations in Toronto, Canada. Toronto Public Health documented complaints of bed bug infestations from 46 locations in 2003, most commonly apartments (63%), shelters (15%), and rooming houses (11%). Pest control operators in Toronto (N = 34) reported treating bed bug infestations at 847 locations in 2003, most commonly single-family dwellings (70%), apartments (18%), and shelters (8%). Bed bug infestations were reported at 20 (31%) of 65 homeless shelters. At 1 affected shelter, 4% of residents reported having bed bug bites. Bed bug infestations can have an adverse effect on health and quality of life in the general population, particularly among homeless persons living in shelters. PMID:15829190

The Influence of Relative Submergence on the Near-bed Flow Field: Implications for Bed-load Transport

NASA Astrophysics Data System (ADS)

Cooper, J.; Tait, S.; Marion, A.

2005-12-01

Bed-load is governed by interdependent mechanisms, the most significant being the interaction between bed roughness, surface layer composition and near-bed flow. Despite this, practically all transport rate equations are described as a function of average bed shear stress. Some workers have examined the role of turbulence in sediment transport (Nelson et al. 1995) but have not explored the potential significance of spatial variations in the near-bed flow field. This is unfortunate considering evidence showing that transport is spatially heterogeneous and could be linked to the spatial nature of the near-bed flow (Drake et al., 1988). An understanding is needed of both the temporal and spatial variability in the near-bed flow field. This paper presents detailed spatial velocity measurements of the near-bed flow field over a gravel-bed, obtained using Particle Image Velocimetry. These data have been collected in a laboratory flume under two regimes: (i) tests with one bed slope and different flow depths; and (ii) tests with a combination of flow depths and slopes at the same average bed shear stress. Results indicate spatial variation in the streamwise velocities of up to 45 per cent from the double-averaged velocity (averaged in both time and space). Under both regimes, as the depth increased, spatial variability in the flow field increased. The probability distributions of near-bed streamwise velocities became progressively more skewed towards the higher velocities. This change was more noticeable under regime (i). This has been combined with data from earlier tests in which the near-bed velocity close to an entraining grain was measured using a PIV/image analysis system (Chegini et al, 2002). This along with data on the shape of the probability density function of velocities capable of entraining individual grains derived from a discrete-particle model (Heald et al., 2004) has been used to estimate the distribution of local velocities required for grain motion in the above tests. The overlap between this distribution and the measured velocities are used to estimate entrainment rates. Predicted entrainment rates increase with relative submergence, even for similar bed shear stress. Assuming bed-load rate is the product of entrainment rate and hop length, and that hop lengths are sensibly stable, suggests that transport rate has a dependence on relative submergence. This demonstrates that transport rate is not a direct function of average bed shear stress. The results describe a mechanism that will cause river channels with contrasting morphologies (and different relative submergence) but similar levels of average bed stress to experience different levels of sediment mobility. Chegini A. Tait S. Heald J. McEwan I. 2002 The development of an automated system for the measurement of near bed turbulence and grain motion. Proc. ASCE Conf. on Hydraulic Measurements and Experimental Methods, ISBN 0-7844-0655-3. Drake T.G. Shreve R.L. Dietrich W.E. Whiting P.J. Leopold L.B. 1988 Bedload transport of fine gravel observed by motion-picture photography, J. Fluid Mech., 192, 193-217. Heald J. McEwan I. Tait, S. 2004 Sediment transport over a flat bed in a unidirectional flow: simulations and validation, Phil. Trans. Roy. Soc. of London A, 362, 1973-1986. Nelson J.M. Shreve R.L. McLean S.R. Drake T.G. 1995 Role of near-bed turbulence structure in bed-load transport and bed form mechanics, Water. Res. Res., 31, 8, 2071-2086.

Temporal and spatial variability in thalweg profiles of a gravel-bed river

USGS Publications Warehouse

Madej, Mary Ann

1999-01-01

This study used successive longitudinal thalweg profiles in gravel-bed rivers to monitor changes in bed topography following floods and associated large sediment inputs. Variations in channel bed elevations, distributions of residual water depths, percentage of channel length occupied by riffles, and a spatial autocorrelation coefficient (Moran's I) were used to quantify changes in morphological diversity and spatial structure in Redwood Creek basin, northwestern California. Bed topography in Redwood Creek and its major tributaries consists primarily of a series of pools and riffles. The size, frequency and spatial distribution of the pools and riffles have changed significantly during the past 20 years. Following large floods and high sediment input in Redwood Creek and its tributaries in 1975, variation in channel bed elevations was low and the percentage of the channel length occupied by riffles was high. Over the next 20 years, variation in bed elevations increased while the length of channel occupied by riffles decreased. An index [(standard deviation of residual water depth/bankfull depth) × 100] was developed to compare variations in bed elevation over a range of stream sizes, with a higher index being indicative of greater morphological diversity. Spatial autocorrelation in the bed elevation data was apparent at both fine and coarse scales in many of the thalweg profiles and the observed spatial pattern of bed elevations was found to be related to the dominant channel material and the time since disturbance. River reaches in which forced pools dominated, and in which large woody debris and bed particles could not be easily mobilized, exhibited a random distribution of bed elevations. In contrast, in reaches where alternate bars dominated, and both wood and gravel were readily transported, regularly spaced bed topography developed at a spacing that increased with time since disturbance. This pattern of regularly spaced bed features was reversed following a 12-year flood when bed elevations became more randomly arranged.

Evaluation of two least toxic integrated pest management programs for managing bed bugs (Heteroptera: Cimicidae) with discussion of a bed bug intercepting device.

PubMed

Wang, Changlu; Gibb, Timothy; Bennett, Gary W

2009-05-01

The cost and effectiveness of two bed bug (Cimex lectularius L.) integrated pest management (IPM) programs were evaluated for 10 wk. Sixteen bed bug-infested apartments were chosen from a high-rise low-income apartment building. The apartments were randomly divided into two treatment groups: diatomaceous earth dust-based IPM (D-IPM) and chlorfenapyr spray-based IPM (S-IPM). The initial median (minimum, maximum) bed bug counts (by visual inspection) of the two treatment groups were 73.5 (10, 352) and 77 (18, 3025), respectively. A seminar and an educational brochure were delivered to residents and staff. It was followed by installing encasements on mattresses and box springs and applying hot steam to bed bug-infested areas in all 16 apartments. Diatomaceous earth dust (Mother Earth-D) was applied in the D-IPM group 2 d after steaming. In addition, bed bug-intercepting devices were installed under legs of infested beds or sofas or chairs to intercept bed bugs. The S-IPM group only received 0.5% chlorfenapyr spray (Phantom) after the nonchemical treatments. All apartments were monitored bi-weekly and retreated when necessary. After 10 wk, bed bugs were eradicated from 50% of the apartments in each group. Bed bug count reduction (mean +/- SEM) was 97.6 +/- 1.6 and 89.7 +/- 7.3% in the D-IPM and S-IPM groups, respectively. Mean treatment costs in the 10-wk period were $463 and $482 per apartment in the D-IPM and S-IPM groups, respectively. Bed bug interceptors trapped an average of 219 +/- 135 bed bugs per apartment in 10 wk. The interceptors contributed to the IPM program efficacy and were much more effective than visual inspections in estimating bed bug numbers and determining the existence of bed bug infestations.

Mother-child bed-sharing trajectories and psychiatric disorders at the age of 6 years.

PubMed

Santos, Iná S; Barros, Aluísio Jd; Barros, Fernando C; Munhoz, Tiago N; Da Silva, Bianca Del Ponte; Matijasevich, Alicia

2017-01-15

Little is known about the effect of bed-sharing with the mother over the child mental health. Population-based birth cohort conducted in Pelotas, Brazil. Children were enrolled at birth (n=4231) and followed-up at 3 months and at 1, 2, 4, and 6 years of age. Bed-sharing was defined as "habitual sharing of the bed between the child and the mother, for sleeping, for part of the night or the whole night". Trajectories of bed sharing between 3 months and 6 years of age were calculated. Mental health was assessed at the age of 6 years using the Development and Well-Being Assessment instrument that generates psychiatric diagnosis according to ICD-10 and DSM-IV criteria. Odds ratios (OR) with 95% confidence intervals were obtained by multivariate logistic regression. 3583 children were analyzed. Four trajectories were identified: non bed-sharers (44.4%), early-only (36.2%), late-onset (12.0%), and persistent bed-sharers (7.4%). In the adjusted analyses persistent bed-sharers were at increased odds of presenting any psychiatric disorder (OR=1.7; 1.2-2.5) and internalizing problems (OR=2.1; 1.4-3.1), as compared to non bed-sharers. Among the early-only bed-sharers OR for any psychiatric disorder was 1.4 (1.1-1.8) and for internalizing problems 1.6 (1.2-2.1). Although the effect of bed-sharing was adjusted for several covariates including the family socio-economic status, maternal mental health and excessive crying, there was no information on maternal personal reasons for bed-sharing. Mothers that bed-share intentionally and those that bed-share in reaction to a child sleep problem may have a different interpretation of their children behavior that may bias the study results. Bed-sharing is a common practice in our setting and is associated with impaired child mental health at the age of six years. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

In-Bed Accountability Development for a Passively Cooled, Electrically Heated Hydride (PACE) Bed

DOE Office of Scientific and Technical Information (OSTI.GOV)

Klein, J.E.

A nominal 1500 STP-L PAssively Cooled, Electrically heated hydride (PACE) Bed has been developed for implementation into a new Savannah River Site tritium project. The 1.2 meter (four-foot) long process vessel contains on internal 'U-tube' for tritium In-Bed Accountability (IBA) measurements. IBA will be performed on six, 12.6 kg production metal hydride storage beds.IBA tests were done on a prototype bed using electric heaters to simulate the radiolytic decay of tritium. Tests had gas flows from 10 to 100 SLPM through the U-tube or 100 SLPM through the bed's vacuum jacket. IBA inventory measurement errors at the 95% confidence levelmore » were calculated using the correlation of IBA gas temperature rise, or (hydride) bed temperature rise above ambient temperature, versus simulated tritium inventory.Prototype bed IBA inventory errors at 100 SLPM were the largest for gas flows through the vacuum jacket: 15.2 grams for the bed temperature rise and 11.5 grams for the gas temperature rise. For a 100 SLPM U-tube flow, the inventory error was 2.5 grams using bed temperature rise and 1.6 grams using gas temperature rise. For 50 to 100 SLPM U-tube flows, the IBA gas temperature rise inventory errors were nominally one to two grams that increased above four grams for flows less than 50 SLPM. For 50 to 100 SLPM U-tube flows, the IBA bed temperature rise inventory errors were greater than the gas temperature rise errors, but similar errors were found for both methods at gas flows of 20, 30, and 40 SLPM.Electric heater IBA tests were done for six production hydride beds using a 45 SLPM U-tube gas flow. Of the duplicate runs performed on these beds, five of the six beds produced IBA inventory errors of approximately three grams: consistent with results obtained in the laboratory prototype tests.« less

In-Bed Accountability Development for a Passively Cooled, Electrically Heated Hydride (PACE) Bed

DOE Office of Scientific and Technical Information (OSTI.GOV)

KLEIN, JAMES

A nominal 1500 STP-L PAssively Cooled, Electrically heated hydride (PACE) Bed has been developed for implementation into a new Savannah River Site tritium project. The 1.2 meter (four-foot) long process vessel contains an internal ''U-tube'' for tritium In-Bed Accountability (IBA) measurements. IBA will be performed on six, 12.6 kg production metal hydride storage beds. IBA tests were done on a prototype bed using electric heaters to simulate the radiolytic decay of tritium. Tests had gas flows from 10 to 100 SLPM through the U-tube or 100 SLPM through the bed's vacuum jacket. IBA inventory measurement errors at the 95 percentmore » confidence level were calculated using the correlation of IBA gas temperature rise, or (hydride) bed temperature rise above ambient temperature, versus simulated tritium inventory. Prototype bed IBA inventory errors at 100 SLPM were the largest for gas flows through the vacuum jacket: 15.2 grams for the bed temperature rise and 11.5 grams for the gas temperature rise. For a 100 SLPM U-tube flow, the inventory error was 2.5 grams using bed temperature rise and 1.6 grams using gas temperature rise. For 50 to 100 SLPM U-tube flows, the IBA gas temperature rise inventory errors were nominally one to two grams that increased above four grams for flows less than 50 SLPM. For 50 to 100 SLPM U-tube flows, the IBA bed temperature rise inventory errors were greater than the gas temperature rise errors, but similar errors were found for both methods at gas flows of 20, 30, and 40 SLPM. Electric heater IBA tests were done for six production hydride beds using a 45 SLPM U-tube gas flow. Of the duplicate runs performed on these beds, five of the six beds produced IBA inventory errors of approximately three grams: consistent with results obtained in the laboratory prototype tests.« less

Complex channel responses to changes in stream flow and sediment supply on the lower Duchesne River, Utah

USGS Publications Warehouse

Gaeuman, D.; Schmidt, J.C.; Wilcock, P.R.

2005-01-01

Channel responses to flow depletions in the lower Duchesne River over the past 100 years have been highly complex and variable in space and time. In general, sand-bed reaches adjusted to all perturbations with bed-level changes, whereas the gravel-bed reaches adjusted primarily through width changes. Gravel-bed reaches aggraded only when gravel was supplied to the channel through local bank erosion and degraded only during extreme flood events. A 50% reduction in stream flow and an increase in fine sediment supply to the study area occurred in the first third of the 20th century. The gravel-bed reach responded primarily with channel narrowing, whereas bed aggradation and four large-scale avulsions occurred in the sand-bed reaches. These avulsions almost completely replaced a section of sinuous channel about 14 km long with a straighter section about 7 km long. The most upstream avulsion, located near a break in valley slope and the transition from a gravel bed upstream and a sand bed downstream, transformed a sinuous sand-bed reach into a braided gravel-bed reach and eventually into a meandering gravel-bed reach over a 30-year period. Later, an increase in flood magnitudes and durations caused widening and secondary bed aggradation in the gravel-bed reaches, whereas the sand-bed reaches incised and narrowed. Water diversions since the 1950s have progressively eliminated moderate flood events, whereas larger floods have been less affected. The loss of frequent flooding has increased the duration and severity of drought periods during which riparian vegetation can establish along the channel margins. As a result, the channel has gradually narrowed throughout the study area since the late 1960s, despite the occasional occurrence of large floods. No tributaries enter the Duchesne River within the study area, so all reaches have experienced identical changes in stream flow and upstream sediment supply. ?? 2004 Elsevier B.V. All rights reserved.

Volatile organic compound adsorption in a gas-solid fluidized bed.

PubMed

Ng, Y L; Yan, R; Tsen, L T S; Yong, L C; Liu, M; Liang, D T

2004-01-01

Fluidization finds many process applications in the areas of catalytic reactions, drying, coating, combustion, gasification and microbial culturing. This work aims to compare the dynamic adsorption characteristics and adsorption rates in a bubbling fluidized bed and a fixed bed at the same gas flow-rate, gas residence time and bed height. Adsorption with 520 ppm methanol and 489 ppm isobutane by the ZSM-5 zeolite of different particle size in the two beds enabled the differentiation of the adsorption characteristics and rates due to bed type, intraparticle mass transfer and adsorbate-adsorbent interaction. Adsorption of isobutane by the more commonly used activated carbon provided the comparison of adsorption between the two adsorbent types. With the same gas residence time of 0.79 seconds in both the bubbling bed and fixed bed of the same bed size of 40 mm diameter and 48 mm height, the experimental results showed a higher rate of adsorption in the bubbling bed as compared to the fixed bed. Intraparticle mass transfer and adsorbent-adsorbate interaction played significant roles in affecting the rate of adsorption, with intraparticle mass transfer being more dominant. The bubbling bed was observed to have a steeper decline in adsorption rate with respect to increasing outlet concentration compared to the fixed bed. The adsorption capacities of zeolite for the adsorbates studied were comparatively similar in both beds; fluidizing, and using smaller particles in the bubbling bed did not increase the adsorption capacity of the ZSM-5 zeolite. The adsorption capacity of activated carbon for isobutane was much higher than the ZSM-5 zeolite for isobutane, although at a lower adsorption rate. Fourier transform infra-red (FTIR) spectroscopy was used as an analytical tool for the quantification of gas concentration. Calibration was done using a series of standards prepared by in situ dilution with nitrogen gas, based on the ideal gas law and relating partial pressure to gas concentration. Concentrations up to 220 ppm for methanol and 75 ppm for isobutane were prepared using this method.