Metalimnetic oxygen minima alter the vertical profiles of carbon dioxide and methane in a managed freshwater reservoir.

PubMed

McClure, Ryan P; Hamre, Kathleen D; Niederlehner, B R; Munger, Zackary W; Chen, Shengyang; Lofton, Mary E; Schreiber, Madeline E; Carey, Cayelan C

2018-04-30

Metalimnetic oxygen minimum zones (MOMs) commonly develop during the summer stratified period in freshwater reservoirs because of both natural processes and water quality management. While several previous studies have examined the causes of MOMs, much less is known about their effects, especially on reservoir biogeochemistry. MOMs create distinct redox gradients in the water column which may alter the magnitude and vertical distribution of dissolved methane (CH 4 ) and carbon dioxide (CO 2 ). The vertical distribution and diffusive efflux of CH 4 and CO 2 was monitored for two consecutive open-water seasons in a eutrophic reservoir that develops MOMs as a result of the operation of water quality engineering systems. During both summers, elevated concentrations of CH 4 accumulated within the anoxic MOM, reaching a maximum of 120 μM, and elevated concentrations of CO 2 accumulated in the oxic hypolimnion, reaching a maximum of 780 μM. Interestingly, the largest observed diffusive CH 4 effluxes occurred before fall turnover in both years, while peak diffusive CO 2 effluxes occurred both before and during turnover. Our data indicate that MOMs can substantially change the vertical distribution of CH 4 and CO 2 in the water column in reservoirs, resulting in the accumulation of CH 4 in the metalimnion (vs. at the sediments) and CO 2 in the hypolimnion. Copyright © 2018 Elsevier B.V. All rights reserved.

Radiation hardness study of semi-insulating GaAs detectors against 5 MeV electrons

NASA Astrophysics Data System (ADS)

Šagátová, A.; Zaťko, B.; Nečas, V.; Sedlačková, K.; Boháček, P.; Fülöp, M.; Pavlovič, M.

2018-01-01

A radiation hardness study of Semi-Insulating (SI) GaAs detectors against 5 MeV electrons is described in this paper. The influence of two parameters, the accumulative absorbed dose (from 1 to 200 kGy) and the applied dose rate (20, 40 or 80 kGy/h), on detector spectrometric properties were studied. The accumulative dose has influenced all evaluated spectrometric properties and also negatively affected the detector CCE (Charge Collection Efficiency). We have observed its systematic reduction from an initial 79% before irradiation down to about 51% at maximum dose of 200 kGy. Relative energy resolution was also influenced by electron irradiation. Its degradation was obvious in the range of doses from 24 up to a maximum dose of 200 kGy, where an increase from 19% up to 31% at 200 V reverse voltage was noticed. On the other hand, a global increase of detection efficiency with accumulative absorbed dose was observed for all samples. Concerning the actual detector degradation we can assume that the tested SI GaAs detectors will be able to operate up to a dose of 300 kGy at least, when irradiated by 5 MeV electrons. The second investigated parameter of irradiation, the dose rate of chosen ranges, did not greatly alter the spectrometric properties of studied detectors.

Model-based intensification of a fed-batch microbial process for the maximization of polyhydroxybutyrate (PHB) production rate.

PubMed

Penloglou, Giannis; Vasileiadou, Athina; Chatzidoukas, Christos; Kiparissides, Costas

2017-08-01

An integrated metabolic-polymerization-macroscopic model, describing the microbial production of polyhydroxybutyrate (PHB) in Azohydromonas lata bacteria, was developed and validated using a comprehensive series of experimental measurements. The model accounted for biomass growth, biopolymer accumulation, carbon and nitrogen sources utilization, oxygen mass transfer and uptake rates and average molecular weights of the accumulated PHB, produced under batch and fed-batch cultivation conditions. Model predictions were in excellent agreement with experimental measurements. The validated model was subsequently utilized to calculate optimal operating conditions and feeding policies for maximizing PHB productivity for desired PHB molecular properties. More specifically, two optimal fed-batch strategies were calculated and experimentally tested: (1) a nitrogen-limited fed-batch policy and (2) a nitrogen sufficient one. The calculated optimal operating policies resulted in a maximum PHB content (94% g/g) in the cultivated bacteria and a biopolymer productivity of 4.2 g/(l h), respectively. Moreover, it was demonstrated that different PHB grades with weight average molecular weights of up to 1513 kg/mol could be produced via the optimal selection of bioprocess operating conditions.

Documentation of a deep percolation model for estimating ground-water recharge

USGS Publications Warehouse

Bauer, H.H.; Vaccaro, J.J.

1987-01-01

A deep percolation model, which operates on a daily basis, was developed to estimate long-term average groundwater recharge from precipitation. It has been designed primarily to simulate recharge in large areas with variable weather, soils, and land uses, but it can also be used at any scale. The physical and mathematical concepts of the deep percolation model, its subroutines and data requirements, and input data sequence and formats are documented. The physical processes simulated are soil moisture accumulation, evaporation from bare soil, plant transpiration, surface water runoff, snow accumulation and melt, and accumulation and evaporation of intercepted precipitation. The minimum data sets for the operation of the model are daily values of precipitation and maximum and minimum air temperature, soil thickness and available water capacity, soil texture, and land use. Long-term average annual precipitation, actual daily stream discharge, monthly estimates of base flow, Soil Conservation Service surface runoff curve numbers, land surface altitude-slope-aspect, and temperature lapse rates are optional. The program is written in the FORTRAN 77 language with no enhancements and should run on most computer systems without modifications. Documentation has been prepared so that program modifications may be made for inclusions of additional physical processes or deletion of ones not considered important. (Author 's abstract)

Nitrogen and phosphorus removal from tertiary wastewater in an osmotic membrane photobioreactor.

PubMed

Praveen, Prashant; Loh, Kai-Chee

2016-04-01

An osmotic membrane photobioreactor (OMPBR) was designed and operated for 162days for nitrogen and phosphorus removal from wastewater using Chlorella vulgaris. The removal efficiency for NH4(+)-N, NO3(-)-N and PO4(3-)-P reached as high as 95%, 53% and 89%, whereas the maximum removal rates were 3.41 mg/L-day, 0.20 mg/L-day and 0.8 mg/L-day, respectively. The microalgae exhibited high tendency to aggregate and attached to the bioreactor and membrane surfaces, and total biomass accumulation in the OMPBR was over 5 g/L. Salt accumulation and biofouling had adverse effects on membrane filtration, but the performance could be recovered through periodic backwashing of the membranes. Extracellular polymeric substances characterization indicated higher fraction of polysaccharides as compared to proteins. The biomass in the OMPBR accumulated higher levels of carbohydrates and chlorophyll. These results indicate the suitability of OMPBR in wastewater treatment and in high-density microalgae cultivation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Accumulate repeat accumulate codes

NASA Technical Reports Server (NTRS)

Abbasfar, Aliazam; Divsalar, Dariush; Yao, Kung

2004-01-01

In this paper we propose an innovative channel coding scheme called 'Accumulate Repeat Accumulate codes' (ARA). This class of codes can be viewed as serial turbo-like codes, or as a subclass of Low Density Parity Check (LDPC) codes, thus belief propagation can be used for iterative decoding of ARA codes on a graph. The structure of encoder for this class can be viewed as precoded Repeat Accumulate (RA) code or as precoded Irregular Repeat Accumulate (IRA) code, where simply an accumulator is chosen as a precoder. Thus ARA codes have simple, and very fast encoder structure when they representing LDPC codes. Based on density evolution for LDPC codes through some examples for ARA codes, we show that for maximum variable node degree 5 a minimum bit SNR as low as 0.08 dB from channel capacity for rate 1/2 can be achieved as the block size goes to infinity. Thus based on fixed low maximum variable node degree, its threshold outperforms not only the RA and IRA codes but also the best known LDPC codes with the dame maximum node degree. Furthermore by puncturing the accumulators any desired high rate codes close to code rate 1 can be obtained with thresholds that stay close to the channel capacity thresholds uniformly. Iterative decoding simulation results are provided. The ARA codes also have projected graph or protograph representation that allows for high speed decoder implementation.

Anaerobic monodigestion of poultry manure: determination of operational parameters for CSTR.

PubMed

Chamy, R; León, C; Vivanco, E; Poirrier, P; Ramos, C

2012-01-01

In this work the anaerobic monodigestion for the treatment of turkey manure was evaluated, without its codigestion with another substrate. The effect of the organic loading rate (OLR) and the substrate concentration (high total solids (TS) concentration) or product concentration (high volatile fatty acids (VFA) and/or ammonia (NH(3)-N) concentrations) was studied. The results show that for a continuous stirred tank reactor (CSTR) operation, a maximum of 40 g/L of TS and 4.0 g/L of ammonium (NH(4)(+)) was required. In addition, the maximum organic loading rate (OLR) will not exceed 1.5 kg VS/m(3)d. Higher TS and NH(4)(+) concentrations and OLR lead to a reduction on the methane productivity and volatile solids (VS) removal. During the CSTR operation, a high alkalinity concentration (above 10 g/L CaCO(3)) was found; this situation allowed maintaining a constant and appropriate pH (close to 7.8), despite the VFA accumulation. In this sense, the alkalinity ratio (α) is a more appropriate control and monitoring parameter of the reactor operation compared to pH. Additionally, with this parameter a VS removal of 80% with a methane productivity of 0.50 m(3)(CH4)/m(3)(R)d is achieved.

[Indoor simulation on dew formation on plant leaves].

PubMed

Gao, Zhi-Yong; Wang, You-Ke; Wei, Xin-Guang; Liu, Shou-Yang; He, Zi-Li; Zhou, Yu-Hong

2014-03-01

Dew forming on plant leaves through water condensation plays a significant ecological role in arid and semi-arid areas as an ignorable fraction of water resources. In this study, an artificial intelligent climate chamber and an automatic temperature-control system for leaves were implemented to regulate the ambient temperature, the leaf surface temperature and the leaf inclination for dew formation. The impact of leaf inclination, ambient temperature and dew point-leaf temperature depression on the rate and quantity of dew accumulation on leaf surface were analyzed. The results indicated that the accumulation rate and the maximum volume of dew on leaves decreased with increasing the leaf inclination while increased with the increment of dew point-leaf temperature depression, ambient temperature and relative humidity. Under the horizontal configuration, dew accumulated linearly on leaf surface over time until the maximum volume (0.80 mm) was reached. However, dew would fall down after reaching the maximum volume when the leaf inclination existed (45 degrees or 90 degrees), significantly slowing down the accumulative rate, and the zigzag pattern for the dynamic of dew accumulation appeared.

Energy Efficiency and Productivity Enhancement of Microbial Electrosynthesis of Acetate

PubMed Central

LaBelle, Edward V.; May, Harold D.

2017-01-01

It was hypothesized that a lack of acetogenic biomass (biocatalyst) at the cathode of a microbial electrosynthesis system, due to electron and nutrient limitations, has prevented further improvement in acetate productivity and efficiency. In order to increase the biomass at the cathode and thereby performance, a bioelectrochemical system with this acetogenic community was operated under galvanostatic control and continuous media flow through a reticulated vitreous carbon (RVC) foam cathode. The combination of galvanostatic control and the high surface area cathode reduced the electron limitation and the continuous flow overcame the nutrient limitation while avoiding the accumulation of products and potential inhibitors. These conditions were set with the intention of operating the biocathode through the production of H2. Biofilm growth occurred on and within the unmodified RVC foam regardless of vigorous H2 generation on the cathode surface. A maximum volumetric rate or space time yield for acetate production of 0.78 g/Lcatholyte/h was achieved with 8 A/Lcatholyte (83.3 A/m2projected surface area of cathode) supplied to the continuous flow/culture bioelectrochemical reactors. The total Coulombic efficiency in H2 and acetate ranged from approximately 80–100%, with a maximum of 35% in acetate. The overall energy efficiency ranged from approximately 35–42% with a maximum to acetate of 12%. PMID:28515713

Energy Efficiency and Productivity Enhancement of Microbial Electrosynthesis of Acetate.

PubMed

LaBelle, Edward V; May, Harold D

2017-01-01

It was hypothesized that a lack of acetogenic biomass (biocatalyst) at the cathode of a microbial electrosynthesis system, due to electron and nutrient limitations, has prevented further improvement in acetate productivity and efficiency. In order to increase the biomass at the cathode and thereby performance, a bioelectrochemical system with this acetogenic community was operated under galvanostatic control and continuous media flow through a reticulated vitreous carbon (RVC) foam cathode. The combination of galvanostatic control and the high surface area cathode reduced the electron limitation and the continuous flow overcame the nutrient limitation while avoiding the accumulation of products and potential inhibitors. These conditions were set with the intention of operating the biocathode through the production of H 2 . Biofilm growth occurred on and within the unmodified RVC foam regardless of vigorous H 2 generation on the cathode surface. A maximum volumetric rate or space time yield for acetate production of 0.78 g/L catholyte /h was achieved with 8 A/L catholyte (83.3 A/m 2 projected surface area of cathode) supplied to the continuous flow/culture bioelectrochemical reactors. The total Coulombic efficiency in H 2 and acetate ranged from approximately 80-100%, with a maximum of 35% in acetate. The overall energy efficiency ranged from approximately 35-42% with a maximum to acetate of 12%.

Accumulation rates and predominant atmospheric sources of natural and anthropogenic Hg and Pb on the Faroe Islands

NASA Astrophysics Data System (ADS)

Shotyk, W.; Goodsite, M. E.; Roos-Barraclough, F.; Givelet, N.; Le Roux, G.; Weiss, D.; Cheburkin, A. K.; Knudsen, K.; Heinemeier, J.; van Der Knaap, W. O.; Norton, S. A.; Lohse, C.

2005-01-01

A monolith representing 5420 14C yr of peat accumulation was collected from a blanket bog at Myrarnar, Faroe Islands. The maximum Hg concentration (498 ng/g at a depth of 4.5 cm) coincides with the maximum concentration of anthropogenic Pb (111 μg/g). Age dating of recent peat accumulation using 210Pb (CRS model) shows that the maxima in Hg and Pb concentrations occur at AD 1954 ± 2. These results, combined with the isotopic composition of Pb in that sample ( 206Pb/ 207Pb = 1.1720 ± 0.0017), suggest that coal burning was the dominant source of both elements. From the onset of peat accumulation (ca. 4286 BC) until AD 1385, the ratios Hg/Br and Hg/Se were constant (2.2 ± 0.5 × 10 -4 and 8.5 ± 1.8 × 10 -3, respectively). Since then, Hg/Br and Hg/Se values have increased, also reaching their maxima in AD 1954. The age date of the maximum concentrations of anthropogenic Hg and Pb in the Faroe Islands is consistent with a previous study of peat cores from Greenland and Denmark (dated using the atmospheric bomb pulse curve of 14C), which showed maximum concentrations in AD 1953. The average rate of atmospheric Hg accumulation from 1520 BC to AD 1385 was 1.27 ± 0.38 μg/m 2/yr. The Br and Se concentrations and the background Hg/Br and Hg/Se ratios were used to calculate the average rate of natural Hg accumulation for the same period, 1.32 ± 0.36 μg/m 2/yr and 1.34 ± 0.29 μg/m 2/yr, respectively. These fluxes are similar to the preanthropogenic rates obtained using peat cores from Switzerland, southern Greenland, southern Ontario, Canada, and the northeastern United States. Episodic volcanic emissions and the continual supply of marine aerosols to the Faroe Islands, therefore, have not contributed significantly to the Hg inventory or the Hg accumulation rates, relative to these other areas. The maximum rate of Hg accumulation was 34 μg/m 2/yr. The greatest fluxes of anthropogenic Hg accumulation calculated using Br and Se, respectively, were 26 and 31 μg/m 2/yr. The rate of atmospheric Hg accumulation in 1998 (16 μg/m 2/yr) is comparable to the values recently obtained by atmospheric transport modeling for Denmark, the Faroe Islands, and Greenland.

Integrated simulations of H-mode operation in ITER including core fuelling, divertor detachment and ELM control

NASA Astrophysics Data System (ADS)

Polevoi, A. R.; Loarte, A.; Dux, R.; Eich, T.; Fable, E.; Coster, D.; Maruyama, S.; Medvedev, S. Yu.; Köchl, F.; Zhogolev, V. E.

2018-05-01

ELM mitigation to avoid melting of the tungsten (W) divertor is one of the main factors affecting plasma fuelling and detachment control at full current for high Q operation in ITER. Here we derive the ITER operational space, where ELM mitigation to avoid melting of the W divertor monoblocks top surface is not required and appropriate control of W sources and radiation in the main plasma can be ensured through ELM control by pellet pacing. We apply the experimental scaling that relates the maximum ELM energy density deposited at the divertor with the pedestal parameters and this eliminates the uncertainty related with the ELM wetted area for energy deposition at the divertor and enables the definition of the ITER operating space through global plasma parameters. Our evaluation is thus based on this empirical scaling for ELM power loads together with the scaling for the pedestal pressure limit based on predictions from stability codes. In particular, our analysis has revealed that for the pedestal pressure predicted by the EPED1  +  SOLPS scaling, ELM mitigation to avoid melting of the W divertor monoblocks top surface may not be required for 2.65 T H-modes with normalized pedestal densities (to the Greenwald limit) larger than 0.5 to a level of current of 6.5–7.5 MA, which depends on assumptions on the divertor power flux during ELMs and between ELMs that expand the range of experimental uncertainties. The pellet and gas fuelling requirements compatible with control of plasma detachment, core plasma tungsten accumulation and H-mode operation (including post-ELM W transient radiation) have been assessed by 1.5D transport simulations for a range of assumptions regarding W re-deposition at the divertor including the most conservative assumption of zero prompt re-deposition. With such conservative assumptions, the post-ELM W transient radiation imposes a very stringent limit on ELM energy losses and the associated minimum required ELM frequency. Depending on W transport assumptions during the ELM, a maximum ELM frequency is also identified above which core tungsten accumulation takes place.

Bioethanol production from Scenedesmus obliquus sugars: the influence of photobioreactors and culture conditions on biomass production.

PubMed

Miranda, J R; Passarinho, P C; Gouveia, L

2012-10-01

A closed-loop vertical tubular photobioreactor (PBR), specially designed to operate under conditions of scarce flat land availability and irregular solar irradiance conditions, was used to study the potential of Scenedesmus obliquus biomass/sugar production. The results obtained were compared to those from an open-raceway pond and a closed-bubble column. The influence of the type of light source and the regime (natural vs artificial and continuous vs light/dark cycles) on the growth of the microalga and the extent of the sugar accumulation was studied in both PBRs. The best type of reactor studied was a closed-loop PBR illuminated with natural light/dark cycles. In all the cases, the relationship between the nitrate depletion and the sugar accumulation was observed. The microalga Scenedesmus was cultivated for 53 days in a raceway pond (4,500 L) and accumulated a maximum sugar content of 29 % g/g. It was pre-treated for carrying out ethanol fermentation assays, and the highest ethanol concentration obtained in the hydrolysate fermented by Kluyveromyces marxianus was 11.7 g/L.

Influence of UV illumination on the cold temperature operation of a LiNbO(3) Q-switched Nd:YAG laser.

PubMed

Cole, Brian; Goldberg, Lew; King, Vernon; Leach, Jeff

2010-04-26

UV illumination of a lithium niobate Q-switch was demonstrated as an effective means to eliminate a loss in hold-off and associated prelasing that occurs under cold temperature operation of Q-switched lasers. This degradation occurs due to the pyroelectric effect, where an accumulation of charge on crystal faces results in a reduction in the Q-switch hold-off and a spatially variable loss of the Q-switch in its high-transmission state, both resulting in lowering of the maximum Q-switched pulse energy. With UV illumination, the resulting creation of photo-generated carriers was shown to be effective in eliminating both of these effects. A Q-switched Nd:YAG laser utilizing UV-illuminated LiNbO(3) was shown to operate under cold temperatures without prelasing or spatially variable loss.

TARN II project

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

Katayama, T.

On the basis of the achievement of the accelerator studies at present TARN, it is decided to construct the new ring TARN II which will be operated as an accumulator, accelerator, cooler and stretcher. It has the maximum magnetic rigidity of 7 Txm corresponding to the proton energy 1.3 GeV and the ring diameter is around 23 m. Light and heavy ions from the SF cyclotron will be injected and accelerated to the working energy where the ring will be operated as a desired mode, for example a cooler ring mode. At the cooler ring operation, the strong cooling devicesmore » such as stochastic and electron beam coolings will work together with the internal gas jet target for the precise nuclear experiments. TARN II is currently under the contruction with the schedule of completion in 1986. In this paper general features of the project are presented.« less

Accumulate-Repeat-Accumulate-Accumulate-Codes

NASA Technical Reports Server (NTRS)

Divsalar, Dariush; Dolinar, Sam; Thorpe, Jeremy

2004-01-01

Inspired by recently proposed Accumulate-Repeat-Accumulate (ARA) codes [15], in this paper we propose a channel coding scheme called Accumulate-Repeat-Accumulate-Accumulate (ARAA) codes. These codes can be seen as serial turbo-like codes or as a subclass of Low Density Parity Check (LDPC) codes, and they have a projected graph or protograph representation; this allows for a high-speed iterative decoder implementation using belief propagation. An ARAA code can be viewed as a precoded Repeat-and-Accumulate (RA) code with puncturing in concatenation with another accumulator, where simply an accumulator is chosen as the precoder; thus ARAA codes have a very fast encoder structure. Using density evolution on their associated protographs, we find examples of rate-lJ2 ARAA codes with maximum variable node degree 4 for which a minimum bit-SNR as low as 0.21 dB from the channel capacity limit can be achieved as the block size goes to infinity. Such a low threshold cannot be achieved by RA or Irregular RA (IRA) or unstructured irregular LDPC codes with the same constraint on the maximum variable node degree. Furthermore by puncturing the accumulators we can construct families of higher rate ARAA codes with thresholds that stay close to their respective channel capacity thresholds uniformly. Iterative decoding simulation results show comparable performance with the best-known LDPC codes but with very low error floor even at moderate block sizes.

Crystallization In High Level Waste (HLW) Glass Melters: Operational Experience From The Savannah River Site

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

Fox, K. M.

2014-02-27

processing strategy for the Hanford Tank Waste Treatment and Immobilization Plant (WTP). The basis of this alternative approach is an empirical model predicting the crystal accumulation in the WTP glass discharge riser and melter bottom as a function of glass composition, time, and temperature. When coupled with an associated operating limit (e.g., the maximum tolerable thickness of an accumulated layer of crystals), this model could then be integrated into the process control algorithms to formulate crystal tolerant high level waste (HLW) glasses targeting higher waste loadings while still meeting process related limits and melter lifetime expectancies. This report provides amore » review of the scaled melter testing that was completed in support of the Defense Waste Processing Facility (DWPF) melter. Testing with scaled melters provided the data to define the DWPF operating limits to avoid bulk (volume) crystallization in the un-agitated DWPF melter and provided the data to distinguish between spinels generated by K-3 refractory corrosion versus spinels that precipitated from the HLW glass melt pool. This report includes a review of the crystallization observed with the scaled melters and the full scale DWPF melters (DWPF Melter 1 and DWPF Melter 2). Examples of actual DWPF melter attainment with Melter 2 are given. The intent is to provide an overview of lessons learned, including some example data, that can be used to advance the development and implementation of an empirical model and operating limit for crystal accumulation for WTP. Operation of the first and second (current) DWPF melters has demonstrated that the strategy of using a liquidus temperature predictive model combined with a 100 °C offset from the normal melter operating temperature of 1150 °C (i.e., the predicted liquidus temperature (TL) of the glass must be 1050 °C or less) has been successful in preventing any detrimental accumulation of spinel in the DWPF melt pool, and spinel has not been observed in any of the pour stream glass samples. Spinel was observed at the bottom of DWPF Melter 1 as a result of K-3 refractory corrosion. Issues have occurred with accumulation of spinel in the pour spout during periods of operation at higher waste loadings. Given that both DWPF melters were or have been in operation for greater than 8 years, the service life of the melters has far exceeded design expectations. It is possible that the DWPF liquidus temperature approach is conservative, in that it may be possible to successfully operate the melter with a small degree of allowable crystallization in the glass. This could be a viable approach to increasing waste loading in the glass assuming that the crystals are suspended in the melt and swept out through the riser and pour spout. Additional study is needed, and development work for WTP might be leveraged to support a different operating limit for the DWPF. Several recommendations are made regarding considerations that need to be included as part of the WTP crystal tolerant strategy based on the DWPF development work and operational data reviewed here. These include: Identify and consider the impacts of potential heat sinks in the WTP melter and glass pouring system; Consider the contributions of refractory corrosion products, which may serve to nucleate additional crystals leading to further accumulation; Consider volatilization of components from the melt (e.g., boron, alkali, halides, etc.) and determine their impacts on glass crystallization behavior; Evaluate the impacts of glass REDuction/OXidation (REDOX) conditions and the distribution of temperature within the WTP melt pool and melter pour chamber on crystal accumulation rate; Consider the impact of precipitated crystals on glass viscosity; Consider the impact of an accumulated crystalline layer on thermal convection currents and bubbler effectiveness within the melt pool; Evaluate the impact of spinel accumulation on Joule heating of the WTP melt pool; and Include noble metals in glass melt experiments because of their potential to act as nucleation sites for spinel crystallization.« less

Phytoremediation of lead (Pb) and arsenic (As) by Melastoma malabathricum L. from contaminated soil in separate exposure.

PubMed

Selamat, S Norleela; Abdullah, S Rozaimah Sheikh; Idris, M

2014-01-01

This study was conducted to investigate the uptake of lead (Pb) and arsenic (As) from contaminated soil using Melastoma malabathricum L. species. The cultivated plants were exposed to As and Pb in separate soils for an observation period of 70 days. From the results of the analysis, M. malabathricum accumulated relatively high range of As concentration in its roots, up to a maximum of 2800 mg/kg. The highest accumulation of As in stems and leaves was 570 mg/kg of plant. For Pb treatment, the highest concentration (13,800 mg/kg) was accumulated in the roots of plants. The maximum accumulation in stems was 880 mg/kg while maximum accumulation in leaves was 2,200 mg/kg. Only small amounts of Pb were translocated from roots to above ground plant parts (TF < 1). However, a wider range of TF values (0.01-23) for As treated plants proved that the translocation of As from root to above ground parts was greater. However, the high capacity of roots to take up Pb and As (BF > 1) is indicative this plants is a good bioaccumulator for these metals. Therefore, phytostabilisation is the mechanism at work in M. malabathricum's uptake of Pb, while phytoextraction is the dominant mechanism with As.

Electrochemical Characterisation of Bio-Bottle-Voltaic (BBV) Systems Operated with Algae and Built with Recycled Materials.

PubMed

Bateson, Peter; Fleet, Jack E H; Riseley, Anthony S; Janeva, Elena; Marcella, Anastasia S; Farinea, Chiara; Kuptsova, Maria; Conde Pueyo, Núria; Howe, Christopher J; Bombelli, Paolo; Parker, Brenda M

2018-04-17

Photobioelectrochemical systems are an emerging possibility for renewable energy. By exploiting photosynthesis, they transform the energy of light into electricity. This study evaluates a simple, scalable bioelectrochemical system built from recycled plastic bottles, equipped with an anode made from recycled aluminum, and operated with the green alga Chlorella sorokiniana . We tested whether such a system, referred to as a bio-bottle-voltaic (BBV) device, could operate outdoors for a prolonged time period of 35 days. Electrochemical characterisation was conducted by measuring the drop in potential between the anode and the cathode, and this value was used to calculate the rate of charge accumulation. The BBV systems were initially able to deliver ~500 mC·bottle −1 ·day −1 , which increased throughout the experimental run to a maximum of ~2000 mC·bottle −1 ·day −1 . The electrical output was consistently and significantly higher than that of the abiotic BBV system operated without algal cells (~100 mC·bottle −1 ·day −1 ). The analysis of the rate of algal biomass accumulation supported the hypothesis that harvesting a proportion of electrons from the algal cells does not significantly perturb the rate of algal growth. Our finding demonstrates that bioelectrochemical systems can be built using recycled components. Prototypes of these systems have been displayed in public events; they could serve as educational toolkits in schools and could also offer a solution for powering low-energy devices off-grid.

Arsenic and other heavy metal accumulation in plants and algae growing naturally in contaminated area of West Bengal, India.

PubMed

Singh, N K; Raghubanshi, A S; Upadhyay, A K; Rai, U N

2016-08-01

The present study was conducted to quantify the arsenic (As) and other heavy metal concentrations in the plants and algae growing naturally in As contaminated blocks of North-24-Pargana and Nandia district, West Bengal, India to assess their bioaccumulation potential. The plant species included five macrophytes and five algae were collected from the nine selected sites for estimation of As and other heavy metals accumulated therein by using Inductively Coupled Plasma Mass Spectrophotometer (ICP-MS). Results revealed that maximum As concentration (117mgkg(-1)) was recorded in the agricultural soil at the Barasat followed by Beliaghat (111mgkg(-1)) sites of North-24-Pargana. Similarly, concentration of selenium (Si, 249mgkg(-1)), lead (Pb, 79.4mgkg(-1)), chromium (Cr, 138mgkg(-1)) was also found maximum in the soil at Barasat and cadmium (Cd, 163mgkg(-1)) nickel (Ni, 36.5mgkg(-1)) at Vijaynagar site. Among the macrophytes, Eichhornia crassipes found more dominating species in As contaminated area and accumulate As (597mgkg(-1)) in the shoot at kanchrapara site. The Lemna minor found to accumulate maximum As (735mgkg(-1)) in the leaves at Sonadanga and Pistia stratiotes accumulated minimum As (24.5mgkg(-1)) in the fronds from Ranaghat site. In case of diatoms, maximum As (760mgkg(-1)) was accumulated at Kanchrapara site followed by Hydrodictiyon reticulatum (403mgkg(-1)) at the Ranaghat site. High concentration of As and other heavy metal in soil indicates long term effects of irrigation with contaminated ground water, however, high concentration of heavy metals in naturally growing plants and algae revealed their mobilization through leaching and possible food chain contamination. Therefore, efficient heavy metal accumulator macrophytes Eichhornia crassipes, Lemna minor, Spirodela polyrhiza may be exploited in removing metals from contaminated water by developing a plant based treatment system. However, As accumulator algal species may be used as a bioresource for understanding algae mediated As detoxification and bioindication studies. Copyright © 2016 Elsevier Inc. All rights reserved.

Association of Fluid Accumulation with Clinical Outcomes in Critically Ill Children with Severe Sepsis

PubMed Central

Chen, Jiao; Li, Xiaozhong; Bai, Zhenjiang; Fang, Fang; Hua, Jun; Li, Ying; Pan, Jian; Wang, Jian; Feng, Xing; Li, Yanhong

2016-01-01

Objective To evaluate whether early and acquired daily fluid overload (FO), as well as fluctuations in fluid accumulation, were associated with adverse outcomes in critically ill children with severe sepsis. Methods This study enrolled 202 children in a pediatric intensive care unit (PICU) with severe sepsis. Early fluid overload was defined as ≥5% fluid accumulation occurring in the first 24 hours of PICU admission. The maximum daily fluid accumulation ≥5% occurring during the next 6 days in patients with at least 48 hours of PICU stay was defined as PICU-acquired daily fluid overload. The fluctuation in fluid accumulation was calculated as the difference between the maximum and the minimum daily fluid accumulation obtained during the first 7 days after admission. Results Of the 202 patients, 61 (30.2%) died during PICU stay. Among all patients, 41 (20.3%) experienced early fluid overload, including 9 with a FO ≥10%. Among patients with at least 48 hours of PICU stay (n = 154), 36 (23.4%) developed PICU-acquired daily fluid overload, including 2 with a FO ≥10%. Both early fluid overload (AOR = 1.20; 95% CI 1.08–1.33; P = 0.001; n = 202) and PICU-acquired daily fluid overload (AOR = 5.47 per log increase; 95% CI 1.15–25.96; P = 0.032; n = 154) were independent risk factors associated with mortality after adjusting for age, illness severity, etc. However, fluctuations in fluid accumulation were not associated with mortality after adjustment. Length of PICU stay increased with greater fluctuations in fluid accumulation in all patients with at least 48 hours of PICU stay (FO <5%, 5%-10% vs. ≥10%: 4 [3–8], 7 [4–11] vs. 10 [6–16] days; P <0.001; n = 154) and in survivors (4 [3–8], 7 [5–11] vs. 10 [5–15] days; P <0.001; n = 121). Early fluid overload achieved an area under-the-receiver-operating-characteristic curve of 0.74 (95% CI 0.65–0.82; P <0.001; n = 202) for predicting mortality in patients with severe sepsis, with a sensitivity of 67.2% and a specificity of 80.1% at the optimal cut-off value of 2.65%. Conclusions Both early and acquired daily fluid overload were independently associated with PICU mortality in children with severe sepsis. PMID:27467522

Sequential decolorization of azo dye and mineralization of decolorization liquid coupled with bioelectricity generation using a pH self-neutralized photobioelectrochemical system operated with polarity reversion.

PubMed

Sun, Jian; Hu, Yongyou; Li, Wanjun; Zhang, Yaping; Chen, Jie; Deng, Feng

2015-05-30

A novel photobioelectrochemical system (PBES) was developed by acclimating algal-bacterial biofilm in both anode and cathode using Chlorella vulgaris and indigenous wastewater bacteria as inoculums. The PBES was operated in polarity reversion mode depend on dark/light alternate reaction to achieve simultaneous pH self-neutralization, azo dye degradation (Congo red) and bioelectricity generation. The anodic accumulated acidity and cathodic accumulated alkalinity were self-neutralized after polarity reversion and hence eliminate the membrane pH gradient. The Congo red was first decolored in the dark anode and the resultant decolorization liquid was subsequently mineralized after the dark anode changing to the photo-biocathode. The presence of C. vulgaris significantly enhanced the two-stage degradation of Congo red, with 93% increases in decolorization rates and 8% increases in mineralization compared to the algae-free BES. The PBES continuously generated stable voltage output over four months under repeatedly reversion of polarity. The maximum power density produced before and after polarity reversion was 78 and 61 mW/m(2), respectively. The synergy between C. vulgaris and mixed bacteria was responsible for the successful operation of the PBES which can be potentially applied to treat wastewater containing azo dye with benefits of enhanced azo dye degradation, high net power output and buffer minimization. Copyright © 2015 Elsevier B.V. All rights reserved.

46 CFR 58.30-25 - Accumulators.

Code of Federal Regulations, 2010 CFR

2010-10-01

... pressure vessel in which energy is stored under high pressure in the form of a gas or a gas and hydraulic... pressures not exceeding the maximum allowable working pressures. When an accumulator forms an integral part...

Regulation of PRPP and nucleoside tri and tetraphosphate pools in Escherichia coli under conditions of nitrogen starvation.

PubMed Central

Villadsen, I S; Michelsen, O

1977-01-01

The ribonucleoside triphosphate, deoxyribonucleoside triphosphate, 3' -diphosphate guanosine 5' -diphosphate (ppGpp), and 5-phosphoribosyl 1-pyrophosphate (PRPP) pools in Escherichia coli B were determined by thin-layer chromatography during changing conditions to ammonium starvation. The intracellular concentrations of all nucleotides were found to change in a well-defined order several minutes before andy observed change in the optical density of the culture. The levels of purine nucleoside triphosphates (adenosine 5' -triphosphate [CTP], dCTP) and uridine nucleotides (uridine 5' -triphosphate, deoxythymidine 5'-triphosphate). The deoxyribonucleotides thus behaved as the ribonucleotides. The levels of ppGpp increased 11-fold after the decrease in uridine nucleotides, when the accumulation of stable ribonucleic acid (RNA) stopped. The level of the nucleotide pool did not stabilize until 30 min after the change in optical density. The pool of dGTP dropped concomitantly with the pool of CTP. The nucleotide precursor PRPP exhibited a transient increase, wtih maximum value of four times the exponential levels at the onset of starvation. Apparently the cell adjusts early to starvation by reducing either the phosphorylating activity or the nucleotide biosynthetic activity. As in other downshift systems, the accumulation of stable RNA stopped before the break in optical density and before the stop in protein accumulation. Cell divisions were quite insensitive to the control mechanisms operating on RNA and protein accumulation under ammonium starvation, since the cells continued to divide for 21 min without any net accumulation of RNA. Images PMID:323222

14 CFR 23.1527 - Maximum operating altitude.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Maximum operating altitude. 23.1527 Section... Information § 23.1527 Maximum operating altitude. (a) The maximum altitude up to which operation is allowed... established. (b) A maximum operating altitude limitation of not more than 25,000 feet must be established for...

Biodegradation of high molecular weight lignin under sulfate reducing conditions: lignin degradability and degradation by-products.

PubMed

Ko, Jae-Jung; Shimizu, Yoshihisa; Ikeda, Kazuhiro; Kim, Seog-Ku; Park, Chul-Hwi; Matsui, Saburo

2009-02-01

This study is designed to investigate the biodegradation of high molecular weight (HMW) lignin under sulfate reducing conditions. With a continuously mesophilic operated reactor in the presence of co-substrates of cellulose, the changes in HMW lignin concentration and chemical structure were analyzed. The acid precipitable polymeric lignin (APPL) and lignin monomers, which are known as degradation by-products, were isolated and detected. The results showed that HMW lignin decreased and showed a maximum degradation capacity of 3.49 mg/l/day. APPL was confirmed as a polymeric degradation by-product and was accumulated in accordance with HMW lignin reduction. We also observed non-linear accumulation of aromatic lignin monomers such as hydrocinnamic acid. Through our experimental results, it was determined that HMW lignin, when provided with a co-substrate of cellulose, is biodegraded through production of APPL and aromatic monomers under anaerobic sulfate reducing conditions with a co-substrate of cellulose.

Accumulate-Repeat-Accumulate-Accumulate Codes

NASA Technical Reports Server (NTRS)

Divsalar, Dariush; Dolinar, Samuel; Thorpe, Jeremy

2007-01-01

Accumulate-repeat-accumulate-accumulate (ARAA) codes have been proposed, inspired by the recently proposed accumulate-repeat-accumulate (ARA) codes. These are error-correcting codes suitable for use in a variety of wireless data-communication systems that include noisy channels. ARAA codes can be regarded as serial turbolike codes or as a subclass of low-density parity-check (LDPC) codes, and, like ARA codes they have projected graph or protograph representations; these characteristics make it possible to design high-speed iterative decoders that utilize belief-propagation algorithms. The objective in proposing ARAA codes as a subclass of ARA codes was to enhance the error-floor performance of ARA codes while maintaining simple encoding structures and low maximum variable node degree.

An integrated biodesulfurization process, including inoculum preparation, desulfurization and sulfate removal in a single step, for removing sulfur from oils.

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

Tangaromsuk, Jantana; Borole, Abhijeet P; Kruatrachue, Maleeya

2008-01-01

BACKGROUND: A single-stage reactor, in which the growth of bacterial culture, induction of desulfurizing enzymes, and desulfurization reaction are carried out in a single step, was adopted to investigate desulfurization of DBT at high cell densities. IGTS8 was used as the biocatalyst. Optimal condition for the bacterial growth and DBT desulfurization were also investigated. RESULTS: Optimization of fermentation conditions was necessary to obtain high cell densities including controlling accumulation of acetate. Under optimal operating conditions, the maximum OD600 was measured to be 26.6 at 118 h of cultivation. When biodesulfurization of DBT in model oil with a high cell densitymore » culture of IGTS8 was investigated, accumulation of sulfate was found to limit the extent of desulfurization. A sulfate removal step was added to obtain a single-stage integrated biodesulfurization process. Sulfate removal was achieved via an aqueous bleed stream and use of a separation unit to recycle the organic phase. CONCLUSION : A proof of principle of a complete system capable of biocatalyst growth, induction, desulfurization and by-product separation was demonstrated. This system enables simplification of the biodesulfurization process and has potential to lower the operating cost of the bioprocess.« less

Accuracy assessment of a net radiation and temperature index snowmelt model using ground observations of snow water equivalent in an alpine basin

NASA Astrophysics Data System (ADS)

Molotch, N. P.; Painter, T. H.; Bales, R. C.; Dozier, J.

2003-04-01

In this study, an accumulated net radiation / accumulated degree-day index snowmelt model was coupled with remotely sensed snow covered area (SCA) data to simulate snow cover depletion and reconstruct maximum snow water equivalent (SWE) in the 19.1-km2 Tokopah Basin of the Sierra Nevada, California. Simple net radiation snowmelt models are attractive for operational snowmelt runoff forecasts as they are computationally inexpensive and have low input requirements relative to physically based energy balance models. The objective of this research was to assess the accuracy of a simple net radiation snowmelt model in a topographically heterogeneous alpine environment. Previous applications of net radiation / temperature index snowmelt models have not been evaluated in alpine terrain with intensive field observations of SWE. Solar radiation data from two meteorological stations were distributed using the topographic radiation model TOPORAD. Relative humidity and temperature data were distributed based on the lapse rate calculated between three meteorological stations within the basin. Fractional SCA data from the Landsat Enhanced Thematic Mapper (5 acquisitions) and the Airborne Visible and Infrared Imaging Spectrometer (AVIRIS) (2 acquisitions) were used to derive daily SCA using a linear regression between acquisition dates. Grain size data from AVIRIS (4 acquisitions) were used to infer snow surface albedo and interpolated linearly with time to derive daily albedo values. Modeled daily snowmelt rates for each 30-m pixel were scaled by the SCA and integrated over the snowmelt season to obtain estimates of maximum SWE accumulation. Snow surveys consisting of an average of 335 depth measurements and 53 density measurements during April, May and June, 1997 were interpolated using a regression tree / co-krig model, with independent variables of average incoming solar radiation, elevation, slope and maximum upwind slope. The basin was clustered into 7 elevation / average-solar-radiation zones for SWE accuracy assessment. Model simulations did a poor job at estimating the spatial distribution of SWE. Basin clusters where the solar radiative flux dominated the melt flux were simulated more accurately than those dominated by the turbulent fluxes or the longwave radiative flux.

49 CFR 192.619 - Maximum allowable operating pressure: Steel or plastic pipelines.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 3 2013-10-01 2013-10-01 false Maximum allowable operating pressure: Steel or... Operations § 192.619 Maximum allowable operating pressure: Steel or plastic pipelines. (a) No person may operate a segment of steel or plastic pipeline at a pressure that exceeds a maximum allowable operating...

49 CFR 192.619 - Maximum allowable operating pressure: Steel or plastic pipelines.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false Maximum allowable operating pressure: Steel or... Operations § 192.619 Maximum allowable operating pressure: Steel or plastic pipelines. (a) No person may operate a segment of steel or plastic pipeline at a pressure that exceeds a maximum allowable operating...

49 CFR 192.619 - Maximum allowable operating pressure: Steel or plastic pipelines.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 3 2012-10-01 2012-10-01 false Maximum allowable operating pressure: Steel or... Operations § 192.619 Maximum allowable operating pressure: Steel or plastic pipelines. (a) No person may operate a segment of steel or plastic pipeline at a pressure that exceeds a maximum allowable operating...

49 CFR 192.619 - Maximum allowable operating pressure: Steel or plastic pipelines.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false Maximum allowable operating pressure: Steel or... Operations § 192.619 Maximum allowable operating pressure: Steel or plastic pipelines. (a) No person may operate a segment of steel or plastic pipeline at a pressure that exceeds a maximum allowable operating...

Carbon stocks and accumulation rates in Pacific Northwest forests: role of stand age, plant community, and productivity

Treesearch

Andrew N. Gray; Thomas R. Whittier; Mark E. Harmon

2016-01-01

Forest ecosystems are removing significant amounts of carbon from the atmosphere. Both abiotic resource availability and biotic interactions during forest succession affect C accumulation rates and maximum C stocks. However, the timing and controls on the peak and decline in C accumulation rates as stands age, trees increase in size, and canopy gaps become prevalent...

An estimation of global solar p-mode frequencies from IRIS network data: 1989-1996

NASA Astrophysics Data System (ADS)

Serebryanskiy, A.; Ehgamberdiev, Sh.; Kholikov, Sh.; Fossat, E.; Gelly, B.; Schmider, F. X.; Grec, G.; Cacciani, A.; Palle, P. L.; Lazrek, M.; Hoeksema, J. T.

2001-06-01

The IRIS network has accumulated full disk helioseismological data since July 1989, i.e. a complete 11-year solar cycle. Since the last paper publishing a frequency list [A&A 317 (1997) L71], not only has the network acquired new data, but has also developed new co-operative programs with compatible instruments [Abstr. SOHO 6/GONG 98 Workshop (1998) 51], so that merging IRIS files with these co-operative program data sets has made possible the improvement of the overall duty cycle. This paper presents new estimations of low degree p-mode frequencies obtained from this IRIS++ data bank covering the period 1989-1996, as well as the variation of their main parameters along the total range of magnetic activity, from before the last maximum to the very minimum. A preliminary estimation of the peak profile asymmetries is also included.

Correlation of different spectral lights with biomass accumulation and production of antioxidant secondary metabolites in callus cultures of medicinally important Prunella vulgaris L.

PubMed

Fazal, Hina; Abbasi, Bilal Haider; Ahmad, Nisar; Ali, Syed Shujait; Akbar, Fazal; Kanwal, Farina

2016-06-01

Light is one of the key elicitors that directly fluctuates plant developmental processes and biosynthesis of secondary metabolites. In this study, the effects of various spectral lights on biomass accumulation and production of antioxidant secondary metabolites in callus cultures of Prunella vulgaris were investigated. Among different spectral lights, green light induced the maximum callogenic response (95%). Enhanced fresh biomass accumulation was observed in log phases on day-35, when callus cultures were exposed to yellow and violet lights. Yellow light induced maximum biomass accumulation (3.67g/100ml) from leaf explants as compared to control (1.27g/100ml). In contrast, violet lights enhanced biomass accumulation (3.49g/100ml) from petiole explant. Maximum total phenolics content (TPC; 23.9mg/g-DW) and total flavonoids content (TFC; 1.65mg/g-DW) were observed when cultures were grown under blue lights. In contrast, green and yellow lights enhanced total phenolics production (TPP; 112.52g/100ml) and total flavonoids production (TFP; 9.64g/100ml) as compared to control. The calli grown under green, red and blue lights enhanced DPPH-free radical scavenging activity (DFRSA; 91.3%, 93.1% and 93%) than control (56.44%) respectively. The DFRSA was correlated either with TPC and TFC or TPP and TFP. Furthermore, yellow lights enhanced superoxide dismutase (SOD), peroxidase (POD) and protease activities, however, the content of total protein (CTP) was higher in control cultures (186μg BSAE/mg FW) as compared to spectral lights. These results suggest that the exposure of callus cultures to various spectral lights have shown a key role in biomass accumulation and production of antioxidant secondary metabolites. Copyright © 2016 Elsevier B.V. All rights reserved.

14 CFR 25.1505 - Maximum operating limit speed.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Maximum operating limit speed. 25.1505... Operating Limitations § 25.1505 Maximum operating limit speed. The maximum operating limit speed (V MO/M MO airspeed or Mach Number, whichever is critical at a particular altitude) is a speed that may not be...

14 CFR 25.1505 - Maximum operating limit speed.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Maximum operating limit speed. 25.1505... Operating Limitations § 25.1505 Maximum operating limit speed. The maximum operating limit speed (V MO/M MO airspeed or Mach Number, whichever is critical at a particular altitude) is a speed that may not be...

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

Vostrotin, Vadim; Birchall, Alan; Zhdanov, Alexey

The distribution of calculated internal doses was determined for 8043 Mayak Production Associate (Mayak PA) workers according to the epidemiological cohorts and groups of raw data used as well as the type of industrial compounds of inhaled aerosols. Statistical characteristics of point estimates of accumulated doses to 17 different tissues and organs and the uncertainty ranges were calculated. Under the MWDS-2013 dosimetry system, the mean accumulated lung dose was 185585 mGy, with a median value of 31 mGy and a maximum of 8980 mGy maximum. The ranges of relative standard uncertainty were: from 40 to 2200% for accumulated lung dose,more » from 25-90% to 2600-3000% for accumulated dose to different regions of respiratory tract, from 13-18% to 2300-2500% for systemic organs and tissues. The Mayak PA workers accumulated internal plutonium lung dose is shown to be close to lognormal. The accumulated internal plutonium dose to systemic organs was close to a log-triangle. The dependency of uncertainty of accumulated absorbed lung and liver doses on the dose estimates itself is also shown. The accumulated absorbed doses to lung, alveolar-interstitial region, liver, bone surface cells and red bone marrow, calculated both with MWDS-2013 and MWDS-2008 have been compared. In general, the accumulated lung doses increased by a factor of 1.8 in median value, while the accumulated doses to systemic organs decreased by factor of 1.3-1.4 in median value. For the cases with identical initial data, accumulated lung doses increased by a factor of 2.1 in median value, while accumulated doses to systemic organs decreased by 8-13% in median value. For the cases with both identical initial data and all of plutonium activity in urine measurements above the decision threshold, accumulated lung doses increased by a factor of 2.8 in median value, while accumulated doses to systemic organs increased by 6-12% in median value.« less

Evaluation of Simultaneous Nutrient and COD Removal with Polyhydroxybutyrate (PHB) Accumulation Using Mixed Microbial Consortia under Anoxic Condition and Their Bioinformatics Analysis

PubMed Central

Jena, Jyotsnarani; Kumar, Ravindra; Dixit, Anshuman; Pandey, Sony; Das, Trupti

2015-01-01

Simultaneous nitrate-N, phosphate and COD removal was evaluated from synthetic waste water using mixed microbial consortia in an anoxic environment under various initial carbon load (ICL) in a batch scale reactor system. Within 6 hours of incubation, enriched DNPAOs (Denitrifying Polyphosphate Accumulating Microorganisms) were able to remove maximum COD (87%) at 2g/L of ICL whereas maximum nitrate-N (97%) and phosphate (87%) removal along with PHB accumulation (49 mg/L) was achieved at 8 g/L of ICL. Exhaustion of nitrate-N, beyond 6 hours of incubation, had a detrimental effect on COD and phosphate removal rate. Fresh supply of nitrate-N to the reaction medium, beyond 6 hours, helped revive the removal rates of both COD and phosphate. Therefore, it was apparent that in spite of a high carbon load, maximum COD and nutrient removal can be maintained, with adequate nitrate-N availability. Denitrifying condition in the medium was evident from an increasing pH trend. PHB accumulation by the mixed culture was directly proportional to ICL; however the time taken for accumulation at higher ICL was more. Unlike conventional EBPR, PHB depletion did not support phosphate accumulation in this case. The unique aspect of all the batch studies were PHB accumulation was observed along with phosphate uptake and nitrate reduction under anoxic conditions. Bioinformatics analysis followed by pyrosequencing of the mixed culture DNA from the seed sludge revealed the dominance of denitrifying population, such as Corynebacterium, Rhodocyclus and Paraccocus (Alphaproteobacteria and Betaproteobacteria). Rarefaction curve indicated complete bacterial population and corresponding number of OTUs through sequence analysis. Chao1 and Shannon index (H’) was used to study the diversity of sampling. “UCI95” and “LCI95” indicated 95% confidence level of upper and lower values of Chao1 for each distance. Values of Chao1 index supported the results of rarefaction curve. PMID:25689047

Evaluation of simultaneous nutrient and COD removal with polyhydroxybutyrate (PHB) accumulation using mixed microbial consortia under anoxic condition and their bioinformatics analysis.

PubMed

Jena, Jyotsnarani; Kumar, Ravindra; Dixit, Anshuman; Pandey, Sony; Das, Trupti

2015-01-01

Simultaneous nitrate-N, phosphate and COD removal was evaluated from synthetic waste water using mixed microbial consortia in an anoxic environment under various initial carbon load (ICL) in a batch scale reactor system. Within 6 hours of incubation, enriched DNPAOs (Denitrifying Polyphosphate Accumulating Microorganisms) were able to remove maximum COD (87%) at 2 g/L of ICL whereas maximum nitrate-N (97%) and phosphate (87%) removal along with PHB accumulation (49 mg/L) was achieved at 8 g/L of ICL. Exhaustion of nitrate-N, beyond 6 hours of incubation, had a detrimental effect on COD and phosphate removal rate. Fresh supply of nitrate-N to the reaction medium, beyond 6 hours, helped revive the removal rates of both COD and phosphate. Therefore, it was apparent that in spite of a high carbon load, maximum COD and nutrient removal can be maintained, with adequate nitrate-N availability. Denitrifying condition in the medium was evident from an increasing pH trend. PHB accumulation by the mixed culture was directly proportional to ICL; however the time taken for accumulation at higher ICL was more. Unlike conventional EBPR, PHB depletion did not support phosphate accumulation in this case. The unique aspect of all the batch studies were PHB accumulation was observed along with phosphate uptake and nitrate reduction under anoxic conditions. Bioinformatics analysis followed by pyrosequencing of the mixed culture DNA from the seed sludge revealed the dominance of denitrifying population, such as Corynebacterium, Rhodocyclus and Paraccocus (Alphaproteobacteria and Betaproteobacteria). Rarefaction curve indicated complete bacterial population and corresponding number of OTUs through sequence analysis. Chao1 and Shannon index (H') was used to study the diversity of sampling. "UCI95" and "LCI95" indicated 95% confidence level of upper and lower values of Chao1 for each distance. Values of Chao1 index supported the results of rarefaction curve.

Production of polyhydroxybutyrate by the marine photosynthetic bacterium Rhodovulum sulfidophilum P5

NASA Astrophysics Data System (ADS)

Cai, Jinling; Wei, Ying; Zhao, Yupeng; Pan, Guanghua; Wang, Guangce

2012-07-01

The effects of different NaCl concentrations, nitrogen sources, carbon sources, and carbon to nitrogen molar ratios on biomass accumulation and polyhydroxybutyrate (PHB) production were studied in batch cultures of the marine photosynthetic bacterium Rhodovulum sulfidophilum P5 under aerobic-dark conditions. The results show that the accumulation of PHB in strain P5 is a growth-associated process. Strain P5 had maximum biomass and PHB accumulation at 2%-3% NaCl, suggesting that the bacterium can maintain growth and potentially produce PHB at natural seawater salinity. In the nitrogen source test, the maximum biomass accumulation (8.10±0.09 g/L) and PHB production (1.11±0.13 g/L and 14.62%±2.2 of the cell dry weight) were observed when peptone and ammonium chloride were used as the sole nitrogen source. NH{4/+}-N was better for PHB production than other nitrogen sources. In the carbon source test, the maximum biomass concentration (7.65±0.05 g/L) was obtained with malic acid as the sole carbon source, whereas the maximum yield of PHB (5.03±0.18 g/L and 66.93%±1.69% of the cell dry weight) was obtained with sodium pyruvate as the sole carbon source. In the carbon to nitrogen ratios test, sodium pyruvate and ammonium chloride were selected as the carbon and nitrogen sources, respectively. The best carbon to nitrogen molar ratio for biomass accumulation (8.77±0.58 g/L) and PHB production (6.07±0.25 g/L and 69.25%±2.05% of the cell dry weight) was 25. The results provide valuable data on the production of PHB by R. sulfidophilum P5 and further studies are on-going for best cell growth and PHB yield.

Effect of boric acid mass transfer on the accumulation thereof in a fuel core under emergency modes at NPPs with WMR

NASA Astrophysics Data System (ADS)

Morozov, A. V.; Sorokin, A. P.; Ragulin, S. V.; Pityk, A. V.; Sahipgareev, A. R.; Soshkina, A. S.; Shlepkin, A. S.

2017-07-01

Boric acid mass transfer processes in the reactor facilities with WMR are considered for the case of an emergency with breaking of the main circulation pipeline (MCP) and the operation of the passive safety systems, such as first-, second-, and third-stage accumulator tank systems, and a passive heat removal system (PHRS). Calculation results are presented for a change in the boric acid concentration in the fuel core (FC) of a water-moderated reactor (WMR) in the case of an emergency process. The calculations have been performed for different values of drop entrainment of boric acid from the reactor (0, 0.2, 2%). A substantial excess of the maximum concentration of boric acid has been found to occur 24 hours after an emergency event with a break of MCP. It is shown that increasing the droplet entrainment of boric acid causes the crystallization and accumulation thereof in the FC to become slower. The mass of boric acid deposits on the elements of internals is determined depending on the values of drop entrainment. These results allow one to draw a conclusion concerning the possibility of accumulation and crystallization of boric acid in the FC, because the latter event could lead to a blocking of the flow cross section and disturbance in the heat removal from fuel elements. A review of available literature data concerning the thermal properties of boric acid solution (density, viscosity, thermal conductivity) is presented. It is found that the available data are of quite a general character, but it does not cover the entire range of parameters (temperature, pressure, acid concentrations) inherent in a possible emergency situation at nuclear power plants with WMR. It is demonstrated that experimental study of boric acid drop entrainment at the parameters inherent in the emergency mode of WMR operation, as well as the studies of boric acid thermal properties in a wide range of concentrations, are required.

14 CFR 27.1527 - Maximum operating altitude.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Maximum operating altitude. 27.1527 Section 27.1527 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... § 27.1527 Maximum operating altitude. The maximum altitude up to which operation is allowed, as limited...

14 CFR 29.1527 - Maximum operating altitude.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Maximum operating altitude. 29.1527 Section 29.1527 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... Limitations § 29.1527 Maximum operating altitude. The maximum altitude up to which operation is allowed, as...

A quantitative study on accumulation of age mass around stagnation points in nested flow systems

NASA Astrophysics Data System (ADS)

Jiang, Xiao-Wei; Wan, Li; Ge, Shemin; Cao, Guo-Liang; Hou, Guang-Cai; Hu, Fu-Sheng; Wang, Xu-Sheng; Li, Hailong; Liang, Si-Hai

2012-12-01

The stagnant zones in nested flow systems have been assumed to be critical to accumulation of transported matter, such as metallic ions and hydrocarbons in drainage basins. However, little quantitative research has been devoted to prove this assumption. In this paper, the transport of age mass is used as an example to demonstrate that transported matter could accumulate around stagnation points. The spatial distribution of model age is analyzed in a series of drainage basins of different depths. We found that groundwater age has a local or regional maximum value around each stagnation point, which proves the accumulation of age mass. In basins where local, intermediate and regional flow systems are all well developed, the regional maximum groundwater age occurs at the regional stagnation point below the basin valley. This can be attributed to the long travel distances of regional flow systems as well as stagnancy of the water. However, when local flow systems dominate, the maximum groundwater age in the basin can be located around the local stagnation points due to stagnancy, which are far away from the basin valley. A case study is presented to illustrate groundwater flow and age in the Ordos Plateau, northwestern China. The accumulation of age mass around stagnation points is confirmed by tracer age determined by 14C dating in two boreholes and simulated age near local stagnation points under different dispersivities. The results will help shed light on the relationship between groundwater flow and distributions of groundwater age, hydrochemistry, mineral resources, and hydrocarbons in drainage basins.

49 CFR 195.406 - Maximum operating pressure.

Code of Federal Regulations, 2010 CFR

2010-10-01

... HAZARDOUS LIQUIDS BY PIPELINE Operation and Maintenance § 195.406 Maximum operating pressure. (a) Except for surge pressures and other variations from normal operations, no operator may operate a pipeline at a... 49 Transportation 3 2010-10-01 2010-10-01 false Maximum operating pressure. 195.406 Section 195...

49 CFR 195.406 - Maximum operating pressure.

Code of Federal Regulations, 2012 CFR

2012-10-01

... HAZARDOUS LIQUIDS BY PIPELINE Operation and Maintenance § 195.406 Maximum operating pressure. (a) Except for surge pressures and other variations from normal operations, no operator may operate a pipeline at a... 49 Transportation 3 2012-10-01 2012-10-01 false Maximum operating pressure. 195.406 Section 195...

49 CFR 195.406 - Maximum operating pressure.

Code of Federal Regulations, 2014 CFR

2014-10-01

... HAZARDOUS LIQUIDS BY PIPELINE Operation and Maintenance § 195.406 Maximum operating pressure. (a) Except for surge pressures and other variations from normal operations, no operator may operate a pipeline at a... 49 Transportation 3 2014-10-01 2014-10-01 false Maximum operating pressure. 195.406 Section 195...

49 CFR 195.406 - Maximum operating pressure.

Code of Federal Regulations, 2011 CFR

2011-10-01

... HAZARDOUS LIQUIDS BY PIPELINE Operation and Maintenance § 195.406 Maximum operating pressure. (a) Except for surge pressures and other variations from normal operations, no operator may operate a pipeline at a... 49 Transportation 3 2011-10-01 2011-10-01 false Maximum operating pressure. 195.406 Section 195...

49 CFR 195.406 - Maximum operating pressure.

Code of Federal Regulations, 2013 CFR

2013-10-01

... HAZARDOUS LIQUIDS BY PIPELINE Operation and Maintenance § 195.406 Maximum operating pressure. (a) Except for surge pressures and other variations from normal operations, no operator may operate a pipeline at a... 49 Transportation 3 2013-10-01 2013-10-01 false Maximum operating pressure. 195.406 Section 195...

Effect of non-feeding period length on the intermittent operation of UASB reactors treating dairy effluents.

PubMed

Coelho, N M; Rodrigues, A A; Arroja, L M; Capela, I F

2007-02-01

Recent environmental concerns have prompted a re-evaluation of conventional management strategies and refueled the search of innovative waste management practices. In this sense, the anaerobic digestion of both fat and the remaining complex organic matter present in dairy wastewaters is attractive, although the continuous operation of high rate anaerobic processes treating this type of wastewaters causes the failure of the process. This work accesses the influence of non-feeding period length on the intermittent operation of mesophilic UASB reactors treating dairy wastewater, in order to allow the biological degradation to catch up with adsorption phenomenon. During the experiments, two UASB reactors were subject to three organic loading rates, ranging from 6 to 12 g(COD) x L(-1) x d(-1), with the same daily load applied to both reactors, each one with a different non-feeding period. Both reactors showed good COD removal efficiencies (87-92%). A material balance for COD in the reactors during the feeding and non-feeding periods showed the importance of the feedless period, which allowed the biomass to degrade substrate that was accumulated during the feeding period. The reactor with the longest non-feeding period had a better performance, which resulted in a higher methane production and adsorption capacity for the same organic load applied with a consequent less accumulation of substrate into the biomass. In addition, both reactors had a stable operation for the organic load of 12 g(COD) x L(-1) x d(-1), which is higher than the maximum applicable load reported in literature for continuous systems (3-6 g(COD) x L(-1) x d(-1)). (c) 2006 Wiley Periodicals, Inc.

Biodegradation of airborne acetone/styrene mixtures in a bubble column reactor.

PubMed

Vanek, T; Silva, A; Halecky, M; Paca, J; Ruzickova, I; Kozliak, E; Jones, K

2017-07-29

The ability of a bubble column reactor (BCR) to biodegrade a mixture of styrene and acetone vapors was evaluated to determine the factors limiting the process efficiency, with a particular emphasis on the presence of degradation intermediates and oxygen levels. The results obtained under varied loadings and ratios were matched with the dissolved oxygen levels and kinetics of oxygen mass transfer, which was assessed by determination of k L a coefficients. A 1.5-L laboratory-scale BCR was operated under a constant air flow of 1.0 L.min -1 , using a defined mixed microbial population as a biocatalyst. Maximum values of elimination capacities/maximum overall specific degradation rates of 75.5 gC.m -3 .h -1 /0.197 gC.gdw -1 .h -1 , 66.0 gC.m -3 .h -1 /0.059 gC.gdw -1 .h -1 , and 45.8 gC.m -3 .h -1 /0.027 gC.gdw -1 .h -1 were observed for styrene/acetone 2:1, styrene-rich and acetone-rich mixtures, respectively, indicating significant substrate interactions and rate limitation by biological factors. The BCR removed both acetone and styrene near-quantitatively up to a relatively high organic load of 50 g.m -3 .h -1 . From this point, the removal efficiencies declined under increasing loading rates, accompanied by a significant drop in the dissolved oxygen concentration, showing a process transition to oxygen-limited conditions. However, the relatively efficient pollutant removal from air continued, due to significant oxygen mass transfer, up to a threshold loading rate when the accumulation of acetone and degradation intermediates in the aqueous medium became significant. These observations demonstrate that oxygen availability is the limiting factor for efficient pollutant degradation and that accumulation of intermediates may serve as an indicator of oxygen limitation. Microbial (activated sludge) analyses revealed the presence of amoebae and active nematodes that were not affected by variations in operational conditions.

Maximum-biomass prediction of homofermentative Lactobacillus.

PubMed

Cui, Shumao; Zhao, Jianxin; Liu, Xiaoming; Chen, Yong Q; Zhang, Hao; Chen, Wei

2016-07-01

Fed-batch and pH-controlled cultures have been widely used for industrial production of probiotics. The aim of this study was to systematically investigate the relationship between the maximum biomass of different homofermentative Lactobacillus and lactate accumulation, and to develop a prediction equation for the maximum biomass concentration in such cultures. The accumulation of the end products and the depletion of nutrients by various strains were evaluated. In addition, the minimum inhibitory concentrations (MICs) of acid anions for various strains at pH 7.0 were examined. The lactate concentration at the point of complete inhibition was not significantly different from the MIC of lactate for all of the strains, although the inhibition mechanism of lactate and acetate on Lactobacillus rhamnosus was different from the other strains which were inhibited by the osmotic pressure caused by acid anions at pH 7.0. When the lactate concentration accumulated to the MIC, the strains stopped growing. The maximum biomass was closely related to the biomass yield per unit of lactate produced (YX/P) and the MIC (C) of lactate for different homofermentative Lactobacillus. Based on the experimental data obtained using different homofermentative Lactobacillus, a prediction equation was established as follows: Xmax - X0 = (0.59 ± 0.02)·YX/P·C. Copyright © 2016. Published by Elsevier B.V.

EFFECT OF VAPOR-PHASE BIOREACTOR OPERATION ON BIOMASS ACCUMULATION, DISTRIBUTION, AND ACTIVITY. (R826168)

EPA Science Inventory

Excess biomass accumulation and activity loss in vapor-phase bioreactors (VPBs) can lead to unreliable long-term operation. In this study, temporal and spatial variations in biomass accumulation, distribution and activity in VPBs treating toluene-contaminated air were monitored o...

Snowpack regimes of the Western United States

NASA Astrophysics Data System (ADS)

Trujillo, Ernesto; Molotch, Noah P.

2014-07-01

Snow accumulation and melt patterns play a significant role in the water, energy, carbon, and nutrient cycles in the montane environments of the Western United States. Recent studies have illustrated that changes in the snow/rainfall apportionments and snow accumulation and melt patterns may occur as a consequence of changes in climate in the region. In order to understand how these changes may affect the snow regimes of the region, the current characteristics of the snow accumulation and melt patterns must be identified. Here we characterize the snow water equivalent (SWE) curve formed by the daily SWE values at 766 snow pillow stations in the Western United States, focusing on several metrics of the yearly SWE curves and the relationships between the different metrics. The metrics are the initial snow accumulation and snow disappearance dates, the peak snow accumulation and date of peak, the length of the snow accumulation season, the length of the snowmelt season, and the snow accumulation and snowmelt slopes. Three snow regimes emerge from these results: a maritime, an intermountain, and a continental regime. The maritime regime is characterized by higher maximum snow accumulations reaching 300 cm and shorter accumulation periods of less than 220 days. Conversely, the continental regime is characterized by lower maximum accumulations below 200 cm and longer accumulation periods reaching over 260 days. The intermountain regime lies in between. The regions that show the characteristics of the maritime regime include the Cascade Mountains, the Klamath Mountains, and the Sierra Nevada Mountains. The intermountain regime includes the Eastern Cascades slopes and foothills, the Blue Mountains, Northern and Central basins and ranges, the Columbia Mountains/Northern Rockies, the Idaho Batholith, and the Canadian Rockies. Lastly, the continental regime includes the Middle and Southern Rockies, and the Wasatch and Uinta Mountains. The implications of snow regime classification are discussed in the context of possible changes in accumulation and melt patterns associated with regional warming.

Assessment of Creep Capability of HSR-EPM Turbine Airfoil Alloys

NASA Technical Reports Server (NTRS)

MacKay, Rebecca A.; Garg, Anita; Ritzert, Frank J.; Locci, Ivan E.

2007-01-01

The High Speed Civil Transport (HSCT) mission of the High Speed Research-Enabling Propulsion Materials (HSR-EPM) Program represented a unique challenge for turbine airfoil materials because the highest operating temperatures occur during climb and supersonic cruise. The accumulated hot time of an HSCT engine before overhaul is many thousands of hours. This is significantly different from subsonic engines, where the maximum operating temperatures occur during takeoff and thrust reverse after landing, and the accumulated hot time before overhaul is about 300 hr. The goal of airfoil alloy development under the HSR-EPM Program was to develop an alloy with a 75 F increase in creep rupture capability over the average Rene N5/PWA 1484 baseline. Airfoil alloy development under the HSR-EPM Program pursued a path that led to evolutionary mechanical behavior improvements, resulting from increased amounts of high density, refractory metals. The purpose of the present paper is to describe the experimental work that was performed at NASA Glenn Research Center after the HSR-EPM Program ended. Emphasis will be placed on the creep behavior of coated specimens, as well as on the development and progression of phase instabilities during creep deformation. Mitigation techniques that were used to reduce phase instabilities are also discussed. Most of the work described in this report was performed at NASA Glenn during the years 2000 and 2001.

An organic water-gated ambipolar transistor with a bulk heterojunction active layer for stable and tunable photodetection

NASA Astrophysics Data System (ADS)

Xu, Haihua; Zhu, Qingqing; Wu, Tongyuan; Chen, Wenwen; Zhou, Guodong; Li, Jun; Zhang, Huisheng; Zhao, Ni

2016-11-01

Organic water-gated transistors (OWGTs) have emerged as promising sensing architectures for biomedical applications and environmental monitoring due to their ability of in-situ detection of biological substances with high sensitivity and low operation voltage, as well as compatibility with various read-out circuits. Tremendous progress has been made in the development of p-type OWGTs. However, achieving stable n-type operation in OWGTs due to the presence of solvated oxygen in water is still challenging. Here, we report an ambipolar OWGT based on a bulk heterojunction active layer, which exhibits a stable hole and electron transport when exposed to aqueous environment. The device can be used as a photodetector both in the hole and electron accumulation regions to yield a maximum responsivity of 0.87 A W-1. More importantly, the device exhibited stable static and dynamic photodetection even when operated in the n-type mode. These findings bring possibilities for the device to be adopted for future biosensing platforms, which are fully compatible with low-cost and low-power organic complementary circuits.

Effect of hydraulic retention time (HRT) on the anaerobic co-digestion of agro-industrial wastes in a two-stage CSTR system.

PubMed

Dareioti, Margarita Andreas; Kornaros, Michael

2014-09-01

A two-stage anaerobic digestion system consisting of two continuously stirred tank reactors (CSTRs) operating at mesophilic conditions (37°C) were used to investigate the effect of hydraulic retention time (HRT) on hydrogen and methane production. The acidogenic reactor was fed with a mixture consisting of olive mill wastewater, cheese whey and liquid cow manure (in a ratio 55:40:5, v/v/v) and operated at five different HRTs (5, 3, 2, 1 and 0.75 d) aiming to evaluate hydrogen productivity and operational stability. The highest system efficiency was achieved at HRT 0.75 d with a maximum hydrogen production rate of 1.72 L/LRd and hydrogen yield of 0.54 mol H2/mol carbohydrates consumed. The methanogenic reactor was operated at HRTs 20 and 25 d with better stability observed at HRT 25 d, whereas accumulation of volatile fatty acids took place at HRT 20 d. The methane production rate at the steady state of HRT 25 d reached 0.33 L CH4/LRd. Copyright © 2014 Elsevier Ltd. All rights reserved.

Development and flight test of metal-lined CFRP cryogenic tank for reusable rocket

NASA Astrophysics Data System (ADS)

Higuchi, Ken; Takeuchi, Shinsuke; Sato, Eiichi; Naruo, Yoshihiro; Inatani, Yoshifumi; Namiki, Fumiharu; Tanaka, Kohtaro; Watabe, Yoko

2005-07-01

A cryogenic tank made of carbon fiber reinforced plastic (CFRP) shell with aluminum thin liner has been designed as a liquid hydrogen (LH2) tank for an ISAS reusable launch vehicle, and the function of it has been proven by repeated flights onboard the test vehicle called reusable vehicle testing (RVT) in October 2003. The liquid hydrogen tank has to be a pressure vessel, because the fuel of the engine of the test vehicle is supplied by fuel pressure. The pressure vessel of a combination of the outer shell of CFRP for strength element at a cryogenic temperature and the inner liner of aluminum for gas barrier has shown excellent weight merit for this purpose. Interfaces such as tank outline shape, bulk capacity, maximum expected operating pressure (MEOP), thermal insulation, pipe arrangement, and measurement of data are also designed to be ready onboard. This research has many aims, not only development of reusable cryogenic composite tank but also the demonstration of repeated operation including thermal cycle and stress cycle, familiarization with test techniques of operation of cryogenic composite tanks, and the accumulation of data for future design of tanks, vehicle structures, safety evaluation, and total operation systems.

49 CFR 192.619 - Maximum allowable operating pressure: Steel or plastic pipelines.

Code of Federal Regulations, 2010 CFR

2010-10-01

... plastic pipelines. 192.619 Section 192.619 Transportation Other Regulations Relating to Transportation... Operations § 192.619 Maximum allowable operating pressure: Steel or plastic pipelines. (a) No person may operate a segment of steel or plastic pipeline at a pressure that exceeds a maximum allowable operating...

High-Performance Bipropellant Engine

NASA Technical Reports Server (NTRS)

Biaglow, James A.; Schneider, Steven J.

1999-01-01

TRW, under contract to the NASA Lewis Research Center, has successfully completed over 10 000 sec of testing of a rhenium thrust chamber manufactured via a new-generation powder metallurgy. High performance was achieved for two different propellants, N2O4- N2H4 and N2O4 -MMH. TRW conducted 44 tests with N2O4-N2H4, accumulating 5230 sec of operating time with maximum burn times of 600 sec and a specific impulse Isp of 333 sec. Seventeen tests were conducted with N2O4-MMH for an additional 4789 sec and a maximum Isp of 324 sec, with a maximum firing duration of 700 sec. Together, the 61 tests totalled 10 019 sec of operating time, with the chamber remaining in excellent condition. Of these tests, 11 lasted 600 to 700 sec. The performance of radiation-cooled rocket engines is limited by their operating temperature. For the past two to three decades, the majority of radiation-cooled rockets were composed of a high-temperature niobium alloy (C103) with a disilicide oxide coating (R512) for oxidation resistance. The R512 coating practically limits the operating temperature to 1370 C. For the Earth-storable bipropellants commonly used in satellite and spacecraft propulsion systems, a significant amount of fuel film cooling is needed. The large film-cooling requirement extracts a large penalty in performance from incomplete mixing and combustion. A material system with a higher temperature capability has been matured to the point where engines are being readied for flight, particularly the 100-lb-thrust class engine. This system has powder rhenium (Re) as a substrate material with an iridium (Ir) oxidation-resistant coating. Again, the operating temperature is limited by the coating; however, Ir is capable of long-life operation at 2200 C. For Earth-storable bipropellants, this allows for the virtual elimination of fuel film cooling (some film cooling is used for thermal control of the head end). This has resulted in significant increases in specific impulse performance (15 to 20 sec). To determine the merits of a powder rhenium thrust chamber, Lewis On-Board Propulsion Branch directed TRW (under the Space Storable Rocket Technology Program and the High Pressure Earth Storable Rocket Technology Program) to design, fabricate, and test an engineering model to serve as a technology demonstrator.

Manipulation of culture strategies to enhance capsaicin biosynthesis in suspension and immobilized cell cultures of Capsicum chinense Jacq. cv. Naga King Chili.

PubMed

Kehie, Mechuselie; Kumaria, Suman; Tandon, Pramod

2014-06-01

Manipulation of culture strategies was adopted to study the influence of nutrient stress, pH stress and precursor feeding on the biosynthesis of capsaicin in suspension and immobilized cell cultures of C. chinense. Cells cultured in the absence of one of the four nutrients (ammonium and potassium nitrate for nitrate and potassium stress, potassium dihydrogen orthophosphate for phosphorus stress, and sucrose for sugar stress) influenced the accumulation of capsaicin. Among the stress factors studied, nitrate stress showed maximal capsaicin production on day 20 (505.9 ± 2.8 μg g(-1) f.wt) in immobilized cell, whereas in suspension cultures the maximum accumulation (345.5 ± 2.9 μg g(-1) f.wt) was obtained on day 10. Different pH affected capsaicin accumulation; enhanced accumulation of capsaicin (261.6 ± 3.4 μg g(-1) f.wt) was observed in suspension cultures at pH 6 on day 15, whereas in case of immobilized cultures the highest capsaicin content (433.3 ± 3.3 μg g(-1) f.wt) was obtained at pH 5 on day 10. Addition of capsaicin precursors and intermediates significantly enhanced the biosynthesis of capsaicin, incorporation of vanillin at 100 μM in both suspension and immobilized cell cultures resulted in maximum capsaicin content with 499.1 ± 5.5 μg g(-1) f.wt on day 20 and 1,315.3 ± 10 μg g(-1) f.wt on day 10, respectively. Among the different culture strategies adopted to enhance capsaicin biosynthesis in cell cultures of C. chinense, cells fed with vanillin resulted in the maximum capsaicin accumulation. The rate of capsaicin production was significantly higher in immobilized cells as compared to freely suspended cells.

Insect contamination protection for laminar flow surfaces

NASA Technical Reports Server (NTRS)

Croom, Cynthia C.; Holmes, Bruce J.

1986-01-01

The ability of modern aircraft surfaces to achieve laminar flow was well-accepted in recent years. Obtaining the maximum benefit of laminar flow for aircraft drag reduction requires maintaining minimum leading-edge contamination. Previously proposed insect contamination prevention methods have proved impractical due to cost, weight, or inconvenience. Past work has shown that insects will not adhere to water-wetted surfaces, but the large volumes of water required for protection rendered such a system impractical. The results of a flight experiment conducted by NASA to evaluate the performance of a porous leading-edge fluid discharge ice protection system operated as an insect contamination protections system are presented. In addition, these flights explored the environmental and atmospheric conditions most suitable for insect accumulation.

rRNA and Poly-β-Hydroxybutyrate Dynamics in Bioreactors Subjected to Feast and Famine Cycles

PubMed Central

Frigon, Dominic; Muyzer, Gerard; van Loosdrecht, Mark; Raskin, Lutgarde

2006-01-01

Feast and famine cycles are common in activated sludge wastewater treatment systems, and they select for bacteria that accumulate storage compounds, such as poly-β-hydroxybutyrate (PHB). Previous studies have shown that variations in influent substrate concentrations force bacteria to accumulate high levels of rRNA compared to the levels in bacteria grown in chemostats. Therefore, it can be hypothesized that bacteria accumulate more rRNA when they are subjected to feast and famine cycles. However, PHB-accumulating bacteria can form biomass (grow) throughout a feast and famine cycle and thus have a lower peak biomass formation rate during the cycle. Consequently, PHB-accumulating bacteria may accumulate less rRNA when they are subjected to feast and famine cycles than bacteria that are not capable of PHB accumulation. These hypotheses were tested with Wautersia eutropha H16 (wild type) and W. eutropha PHB-4 (a mutant not capable of accumulating PHB) grown in chemostat and semibatch reactors. For both strains, the cellular RNA level was higher when the organism was grown in semibatch reactors than when it was grown in chemostats, and the specific biomass formation rates during the feast phase were linearly related to the cellular RNA levels for cultures. Although the two strains exhibited maximum uptake rates when they were grown in semibatch reactors, the wild-type strain responded much more rapidly to the addition of fresh medium than the mutant responded. Furthermore, the chemostat-grown mutant culture was unable to exhibit maximum substrate uptake rates when it was subjected to pulse-wise addition of fresh medium. These data show that the ability to accumulate PHB does not prevent bacteria from accumulating high levels of rRNA when they are subjected to feast and famine cycles. Our results also demonstrate that the ability to accumulate PHB makes the bacteria more responsive to sudden increases in substrate concentrations, which explains their ecological advantage. PMID:16597926

rRNA and poly-beta-hydroxybutyrate dynamics in bioreactors subjected to feast and famine cycles.

PubMed

Frigon, Dominic; Muyzer, Gerard; van Loosdrecht, Mark; Raskin, Lutgarde

2006-04-01

Feast and famine cycles are common in activated sludge wastewater treatment systems, and they select for bacteria that accumulate storage compounds, such as poly-beta-hydroxybutyrate (PHB). Previous studies have shown that variations in influent substrate concentrations force bacteria to accumulate high levels of rRNA compared to the levels in bacteria grown in chemostats. Therefore, it can be hypothesized that bacteria accumulate more rRNA when they are subjected to feast and famine cycles. However, PHB-accumulating bacteria can form biomass (grow) throughout a feast and famine cycle and thus have a lower peak biomass formation rate during the cycle. Consequently, PHB-accumulating bacteria may accumulate less rRNA when they are subjected to feast and famine cycles than bacteria that are not capable of PHB accumulation. These hypotheses were tested with Wautersia eutropha H16 (wild type) and W. eutropha PHB-4 (a mutant not capable of accumulating PHB) grown in chemostat and semibatch reactors. For both strains, the cellular RNA level was higher when the organism was grown in semibatch reactors than when it was grown in chemostats, and the specific biomass formation rates during the feast phase were linearly related to the cellular RNA levels for cultures. Although the two strains exhibited maximum uptake rates when they were grown in semibatch reactors, the wild-type strain responded much more rapidly to the addition of fresh medium than the mutant responded. Furthermore, the chemostat-grown mutant culture was unable to exhibit maximum substrate uptake rates when it was subjected to pulse-wise addition of fresh medium. These data show that the ability to accumulate PHB does not prevent bacteria from accumulating high levels of rRNA when they are subjected to feast and famine cycles. Our results also demonstrate that the ability to accumulate PHB makes the bacteria more responsive to sudden increases in substrate concentrations, which explains their ecological advantage.

Effect of temperature and dissolved oxygen on biological nitrification at high ammonia concentrations.

PubMed

Weon, S Y; Lee, S I; Koopman, B

2004-11-01

Effect of temperature and dissolved oxygen concentration on nitrification rate were investigated with enrichment cultures of nitrifying bacteria. Values of specific nitrite oxidation rate in the absence of ammonia were 2.9-12 times higher than maximum specific ammonia oxidation rates at the same temperatures. The presence of high ammonia levels reversed this relationship, causing maximum specific nitrite oxidation rates to fall to 19 to 45% as high as maximum specific ammonia oxidation rates. This result suggests that nitrification at high ammonia levels will invariably result in nitrite accumulation. The K(O2) for nitrite oxidation in the presence of high ammonia levels was higher than the K(O2) for ammonia oxidation when temperature exceeded 18 degrees C, whereas the opposite was true at lower temperatures. These results indicate that low oxygen tensions will exacerbate nitrite accumulation when water temperature is high.

Effect of pulsed electric fields upon accumulation of zinc in Saccharomyces cerevisiae.

PubMed

Pankiewicz, Urszula; Jamroz, Jerzy

2011-06-01

Cultures of Saccharomyces cerevisiae were treated with pulsed electric fields to improve accumulation of zinc in the biomass. Under optimized conditions, that is, on 15 min exposure of the 20 h grown culture to PEFs of 1500 V and 10 microns pulse width, accumulation of zinc in the yeast biomass reached a maximum of 15.57 mg/g d.m. Under optimum zinc concentration (100 microgram/ml nutrient medium), its accumulation in the cells was higher by 63% in comparison with the control (without PEFs). That accumulation significantly correlated against zinc concentration in the medium. Neither multiple exposure of the cultures to PEFs nor intermittent supplementation of the cultures with zinc increased the zinc accumulation. The intermittent supplementation of the cultures with zinc and multiple exposures on PEFs could even reduce the accumulation efficiency, respectively, by 57% and 47%.

Snowpack Regimes of the Western United States

NASA Astrophysics Data System (ADS)

Trujillo, E.; Molotch, N. P.

2011-12-01

Snow accumulation and melt patterns play a significant role in the water, energy, carbon and nutrient cycles in the montane environments of the Western United States. Recent studies have illustrated that changes in the snow/rainfall apportionments, and snow accumulation and melt patterns may occur as a consequence of changes in climate in the region. In order to understand how these changes may affect the snow regimes of the region, the current characteristics of the snow accumulation and melt patterns must be identified. Here, we characterize the snow water equivalent (SWE) curve formed by the daily SWE values at over seven hundred snow pillow stations in the Western U.S., focusing on several metrics of the yearly SWE curves and the cross relationships between the different metrics. The metrics include the initial snow accumulation and meltout dates, the peak accumulation and date of peak, the time from initial accumulation to peak, the time from peak to meltout, the accumulation and melt slopes, and the daily rates of accumulation and melt. Three distinct regimes emerge from these results: a maritime, an intermediate (intercontinental), and a continental regime. The maritime regime is characterized by higher maximum snow accumulations reaching 300 cm and shorter accumulation periods of less than 220 days, while on the other hand; the continental regime is characterized by lower maximum accumulations below 200 cm and longer accumulation periods reaching over 260 days. The intercontinental regime lies in between. Several other differences are identified between the metrics of the SWE curve in these regimes. The regions that show the characteristics of the maritime regime include the Cascade Mountains, the Klamath Mountains, and the Sierra Nevada Mountains. The intercontinental regime includes the Northern and Central basins and ranges, the Idaho Batholith, the Northern Rockies and the Blue Mountains. Lastly, the Continental regime includes the Middle and Southern Rockies, and the Wasatch and Uinta Mountains. The consequences of the differences between these snow regimes are discussed in the framework of the implications of possible changes in accumulation and melt patterns as a consequence of changes in climate.

Hydrolysis and acidification of agricultural waste in a non-airtight system: Effect of solid content, temperature, and mixing mode.

PubMed

Yu, Jiadong; Zhao, Yubin; Zhang, Huan; Hua, Binbin; Yuan, Xufeng; Zhu, Wanbin; Wang, Xiaofen; Cui, Zongjun

2017-01-01

A two-phase digestion system for treating agricultural waste is beneficial for methane production. This study explored the effect of solid content, temperature, and mixing mode on the process of hydrolysis and acidification using rice straw and cow dung launched in non-airtight acidogenic system. The results showed that the substrate could be hydrolyzed efficiently in the initial stage, the hydrolysis coefficient (k) of maximum cellulose and hemicellulose can be increased by 217.9% and 290.5%, respectively, compared with those of middle and last stages. High solid content played a leading role in promoting hydrolysis, resulted in hydrolysate content (sCOD) that was significantly higher than in treatments with low solid content (P<0.01), and led to organic acids accumulation up to 5.8 and 6.7g/L at mesophilic and thermophilic temperatures. Thermophilic temperature stimulated the hydrolysis and acidification of low solid content (P<0.05), and improved organic acid accumulation of high solid content only during the middle stage (P<0.01). Mixing mode was not a major factor, but increasing the mixing time was necessary for organic acid accumulation during the last stage (P<0.05). In addition, the study comprehensively analyzed a series of corresponding relationships among each operating parameter during the whole treatment process using canonical correspondence analysis. Copyright © 2016 Elsevier Ltd. All rights reserved.

Preliminary Results of an Altitude-Wind-Tunnel Investigation of an Axial-Flow Gas Turbine-Propeller Engine. 4; Compressor and Turbine Performance Characteristics

NASA Technical Reports Server (NTRS)

Wallner, Lewis E.; Saari, Martin J.

1948-01-01

As part of an investigation of the performance and operational characteristics of the axial-flow gas turbine-propeller engine, conducted in the Cleveland altitude wind tunnel, the performance characteristics of the compressor and the turbine were obtained. The data presented were obtained at a compressor-inlet ram-pressure ratio of 1.00 for altitudes from 5000 to 35,000 feet, engine speeds from 8000 to 13,000 rpm, and turbine-inlet temperatures from 1400 to 2100 R. The highest compressor pressure ratio obtained was 6.15 at a corrected air flow of 23.7 pounds per second and a corrected turbine-inlet temperature of 2475 R. Peak adiabatic compressor efficiencies of about 77 percent were obtained near the value of corrected air flow corresponding to a corrected engine speed of 13,000 rpm. This maximum efficiency may be somewhat low, however, because of dirt accumulations on the compressor blades. A maximum adiabatic turbine efficiency of 81.5 percent was obtained at rated engine speed for all altitudes and turbine-inlet temperatures investigated.

Preliminary Results of an Altitude-Wind-Tunnel Investigation of a TG-100A Gas Turbine-Propeller Engine. 4; Compressor and Turbine Performance Characteristics

NASA Technical Reports Server (NTRS)

Wallner, Lewis E.; Saari, Martin J.

1947-01-01

As part of an investigation of the performance and operational characteristics of the TG-100A gas turbine-propeller engine, conducted in the Cleveland altitude wind tunnel, the performance characteristics of the compressor and the turbine were obtained. The data presented were obtained at a compressor-inlet ram-pressure ratio of 1.00 for altitudes from 5000 to 35,000 feet, engine speeds from 8000 to 13,000 rpm, and turbine-inlet temperatures from 1400 to 2100R. The highest compressor pressure ratio was 6.15 at a corrected air flow of 23.7 pounds per second and a corrected turbine-inlet temperature of 2475R. Peak adiabatic compressor efficiencies of about 77 percent were obtained near the value of corrected air flow corresponding to a corrected engine speed of 13,000 rpm. This maximum efficiency may be somewhat low, however, because of dirt accumulations on the compressor blades. A maximum adiabatic turbine efficiency of 81.5 percent was obtained at rated engine speed for all altitudes and turbine-inlet temperatures investigated.

49 CFR 229.49 - Main reservoir system.

Code of Federal Regulations, 2014 CFR

2014-10-01

... least one safety valve that shall prevent an accumulation of pressure of more than 15 pounds per square... or unloads and loads the air compressor within 5 pounds per square inch above or below the maximum... pressure is not less than 15 pounds per square inch above the maximum brake pipe pressure fixed by the...

49 CFR 229.49 - Main reservoir system.

Code of Federal Regulations, 2010 CFR

2010-10-01

... least one safety valve that shall prevent an accumulation of pressure of more than 15 pounds per square... or unloads and loads the air compressor within 5 pounds per square inch above or below the maximum... pressure is not less than 15 pounds per square inch above the maximum brake pipe pressure fixed by the...

Future risk assessment by estimating historical heat wave trends with projected heat accumulation using SimCLIM climate model in Pakistan

NASA Astrophysics Data System (ADS)

Nasim, Wajid; Amin, Asad; Fahad, Shah; Awais, Muhammad; Khan, Naeem; Mubeen, Muhammad; Wahid, Abdul; Turan, Veysel; Rehman, Muhammad Habibur; Ihsan, Muhammad Zahid; Ahmad, Shakeel; Hussain, Sajjad; Mian, Ishaq Ahmad; Khan, Bushra; Jamal, Yousaf

2018-06-01

Climate change has adverse effects at global, regional and local level. Heat wave events have serious contribution for global warming and natural hazards in Pakistan. Historical (1997-2015) heat wave were analyzed over different provinces (Punjab, Sindh and Baluchistan) of Pakistan to identify the maximum temperature trend. Heat accumulation in Pakistan were simulated by the General Circulation Model (GCM) combined with 3 GHG (Green House Gases) Representative Concentration Pathways (RCPs) (RCP-4.5, 6.0, and 8.5) by using SimCLIM model (statistical downscaling model for future trend projections). Heat accumulation was projected for year 2030, 2060, and 2090 for seasonal and annual analysis in Pakistan. Heat accumulation were projected to increase by the baseline year (1995) was represented in percentage change. Projection shows that Sindh and southern Punjab was mostly affected by heat accumulation. This study identified the rising trend of heat wave over the period (1997-2015) for Punjab, Sindh and Baluchistan (provinces of Pakistan), which identified that most of the meteorological stations in Punjab and Sindh are highly prone to heat waves. According to model projection; future trend of annual heat accumulation, in 2030 was increased 17%, 26%, and 32% but for 2060 the trends were reported by 54%, 49%, and 86% for 2090 showed highest upto 62%, 75%, and 140% for RCP-4.5, RCP-6.0, and RCP-8.5, respectively. While seasonal trends of heat accumulation were projected to maximum values for monsoon and followed by pre-monsoon and post monsoon. Heat accumulation in monsoon may affect the agricultural activities in the region under study.

Experimental investigation of a packed bed thermal energy storage system

NASA Astrophysics Data System (ADS)

Cascetta, Mario; Cau, Giorgio; Puddu, Pierpaolo; Serra, Fabio

2015-11-01

In this work experimental investigations on a thermal energy storage system with a solid material as storage media and air as heat transfer fluid will be presented. The experimental test rig, installed at the DIMCM of the University of Cagliari, consists of a carbon steel tank filled with freely poured alumina beads that allows investigations of heat transfer phenomena in packed beds. The aim of this work is to show the influence of the operating conditions and physical parameters on thermocline formation and, in particular, the thermal behaviour of the thermal energy storage for repeated charging and discharging cycles. Better charging efficiency is obtained for lower values of mass flow rate and maximum air temperature and for increasing aspect ratio. A decreasing influence of the metal wall with continuous operation is also highlighted. In conclusion, the analysis focuses on the thermal hysteresis phenomenon, which causes degradation of the thermocline and the reduction of the energy that can be stored by the accumulator as the repeated number of cycles increases.

Destructive Evaluation of a Xenon Hollow Cathode after a 28,000 Hour Life Test

NASA Technical Reports Server (NTRS)

Sarver-Verhey, Timothy R.

1998-01-01

International Space Station (ISS) plasma contactor system requires a hollow cathode assembly (HCA) with a lifetime of at least 18,000 hours. In order to demonstrate the lifetime capability of the HCA, a series of hollow cathode wear tests was performed which included a life test operated at the maximum current of the HCA. This test sought to verify hollow cathode lifetime capability and contamination control protocols. This hollow cathode accumulated 27,800 hours of operation before it failed during a restart attempt. The cathode was subsequently destructively analyzed in order to determine the failure mechanism. Microscopic examination of the cathode interior determined that relatively small changes in the cathode physical geometry had occurred and barium tungstates, which are known to limit the emission process, had formed over a majority of the electron emitter surface. Because the final state of the insert was consistent with expected impregnate chemistry, the hollow cathode was believed to have reached the end of its usable life under the test conditions.

Efficient butanol-ethanol (B-E) production from carbon monoxide fermentation by Clostridium carboxidivorans.

PubMed

Fernández-Naveira, Ánxela; Abubackar, Haris Nalakath; Veiga, María C; Kennes, Christian

2016-04-01

The fermentation of waste gases rich in carbon monoxide using acetogens is an efficient way to obtain valuable biofuels like ethanol and butanol. Different experiments were carried out with the bacterial species Clostridium carboxidivorans as biocatalyst. In batch assays with no pH regulation, after complete substrate exhaustion, acetic acid, butyric acid, and ethanol were detected while only negligible butanol production was observed. On the other side, in bioreactors, with continuous carbon monoxide supply and pH regulation, both C2 and C4 fatty acids were initially formed as well as ethanol and butanol at concentrations never reported before for this type of anaerobic bioconversion of gaseous C1 compounds, showing that the operating conditions significantly affect the metabolic fermentation profile and butanol accumulation. Maximum ethanol and butanol concentrations in the bioreactors were obtained at pH 5.75, reaching values of 5.55 and 2.66 g/L, respectively. The alcohols were produced both from CO fermentation as well as from the bioconversion of previously accumulated acetic and butyric acids, resulting in low residual concentrations of such acids at the end of the bioreactor experiments. CO consumption was often around 50% and reached up to more than 80%. Maximum specific rates of ethanol and butanol production were reached at pH 4.75, with values of 0.16 g/h*g of biomass and 0.07 g/h*g of biomass, respectively, demonstrating that a low pH was more favorable to solventogenesis in this process, although it negatively affects biomass growth which does also play a role in the final alcohol titer.

Libya, Algeria and Egypt: crude oil potential from known deposits

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

Dietzman, W.D.; Rafidi, N.R.; Ross, T.A.

1982-04-01

An analysis is presented of the discovered crude oil resources, reserves, and estimated annual production from known fields of the Republics of Libya, Algeria, and Egypt. Proved reserves are defined as the remaining producible oil as of a specified date under operating practice in effect at that time and include estimated recoverable oil in undrilled portions of a given structure or structures. Also included in the proved reserve category are the estimated indicated additional volumes of recoverable oil from the entire oil reservoir where fluid injection programs have been started in a portion, or portions, of the reservoir. The indicatedmore » additional reserves (probable reserves) reported herein are the volumes of crude oil that might be obtained with the installation of secondary recovery or pressure maintenance operations in reservoirs where none have been previously installed. The sum of cumulative production, proved reserves, and probable reserves is defined as the ultimate oil recovery from known deposits; and resources are defined as the original oil in place (OOIP). An assessment was made of the availability of crude oil under three assumed sustained production rates for each country; an assessment was also made of each country's capability of sustaining production at, or near, the 1980 rates assuming different limiting reserve to production ratios. Also included is an estimate of the potential maximum producing capability from known deposits that might be obtained from known accumulations under certain assumptions, using a simple time series approach. The theoretical maximum oil production capability from known fields at any time is the maximum deliverability rate assuming there are no equipment, investment, market, or political constraints.« less

[Hydroxylamine conversion by anammox enrichment].

PubMed

Hu, Anhui; Zheng, Ping; Lu, Huifeng; Ding, Shuang; Wang, Caihua

2010-04-01

Hydroxylamine is an important intermediate product of anammox. This study was focused on the characteristics of hydroxylamine and nitrite conversions by anammox enrichment. The changes of nitrogenous substrates and related products with time were measured using batch tests with anammox enrichment as inoculum. Since hydroxylamine didn't react with nitrite in uninoculated control culture, these two compounds were chemically stable. Both of them decreased with time in anammox enrichment inoculated cultures, in which ammonia as intermediate product would be produced and converted with the maximum concentration being 0.338 mg/L. The total nitrogen concentration decreased from 4.694 mmol/L to 0.812 mmol/L with conversion rate 82.7% in the end. When hydroxylamine and nitrite concentrations were about 2.5 mmol/L respectively, the maximum specific sludge conversion rates of hydroxylamine was 0.535 mmol/(gVSS.h), which was 1.81 times bigger than that of ammonia in ammonia reaction system; the maximum specific sludge rate of total nitrogen was slightly higher than that in ammonia reaction system. When hydroxylamine concentration increased to 5.0 mmol/L, the hydroxylamine and nitrite conversion rates promoted by 26.7% and 120.7% respectively; and the maximum ammonia accumulated was 1.810 mmol/L. When nitrite concentration increased to 5.0 mmol/L, the hydroxylamine and nitrite conversion rates promoted by 6.9% and 9.0% respectively; and the maximum ammonia accumulated was 0.795 mmol/L. Anammox enrichment was capable of converting hydroxylamine and nitrite simultaneously and had the higher conversion rate of hydroxylamine than ammonia conversion rate. Hydroxylamine and nitrite conversion rates were less affected by increase in nitrite concentration, but more significantly influenced by increase in hydroxylamine. The maximum ammonia concentration accumulated would rise as the result of increasing both hydroxylamine and nitrite. The result of experiment was consistent with pathway model presented by van de Graaf AA.

49 CFR 174.86 - Maximum allowable operating speed.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 2 2011-10-01 2011-10-01 false Maximum allowable operating speed. 174.86 Section... operating speed. (a) For molten metals and molten glass shipped in packagings other than those prescribed in § 173.247 of this subchapter, the maximum allowable operating speed may not exceed 24 km/hour (15 mph...

49 CFR 174.86 - Maximum allowable operating speed.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false Maximum allowable operating speed. 174.86 Section... operating speed. (a) For molten metals and molten glass shipped in packagings other than those prescribed in § 173.247 of this subchapter, the maximum allowable operating speed may not exceed 24 km/hour (15 mph...

The Maximum standardized uptake value is more reliable than size measurement in early follow-up to evaluate potential pulmonary malignancies following radiofrequency ablation.

PubMed

Alafate, Aierken; Shinya, Takayoshi; Okumura, Yoshihiro; Sato, Shuhei; Hiraki, Takao; Ishii, Hiroaki; Gobara, Hideo; Kato, Katsuya; Fujiwara, Toshiyoshi; Miyoshi, Shinichiro; Kaji, Mitsumasa; Kanazawa, Susumu

2013-01-01

We retrospectively evaluated the accumulation of fluorodeoxy glucose (FDG) in pulmonary malignancies without local recurrence during 2-year follow-up on positron emission tomography (PET)/computed tomography (CT) after radiofrequency ablation (RFA). Thirty tumors in 25 patients were studied (10 non-small cell lung cancers;20 pulmonary metastatic tumors). PET/CT was performed before RFA, 3 months after RFA, and 6 months after RFA. We assessed the FDG accumulation with the maximum standardized uptake value (SUVmax) compared with the diameters of the lesions. The SUVmax had a decreasing tendency in the first 6 months and, at 6 months post-ablation, FDG accumulation was less affected by inflammatory changes than at 3 months post-RFA. The diameter of the ablated lesion exceeded that of the initial tumor at 3 months post-RFA and shrank to pre-ablation dimensions by 6 months post-RFA. SUVmax was more reliable than the size measurements by CT in the first 6 months after RFA, and PET/CT at 6 months post-RFA may be more appropriate for the assessment of FDG accumulation than that at 3 months post-RFA.

Agrometeorological parameters for prediction of the maturation period of Arabica coffee cultivars

NASA Astrophysics Data System (ADS)

Pezzopane, José Ricardo Macedo; Salva, Terezinha de Jesus Garcia; de Lima, Valéria Bittencourt; Fazuoli, Luiz Carlos

2012-09-01

The objective of this study was to determine the harvest period of coffee fruits based on the relationship between agrometeorological parameters and sucrose accumulation in the seeds. Over the crop years 2004/2005 and 2006/2007, from 150 days after flowering (DAF) onwards, samples of 50 fruits of cultivars Mundo Novo IAC 376-4, Obatã IAC 1669-20 and Catuaí Vermelho IAC 144 were collected from coffee trees located in Campinas, Brazil. The endosperm of the fruits was freeze-dried, ground and analyzed for sucrose content by high-performance liquid chromatography. A weather station provided data to calculate the accumulated growing degree-day (GDD) units, and the reference (ETo) and actual (ETr) evapotranspiration rates. The results showed that the highest rates of sucrose accumulation occurred at the transition from the cane-green to the cherry phenological stage. Models for the estimation of sucrose content during maturation based on meteorological variables exhibited similar or better performance than the DAF variable, with better results for the variables GDD and ETo. The Mundo Novo cultivar reached the highest sucrose level in the endosperm after 2,790 GDD, while cultivar Catuaí attained its maximum sucrose concentration after the accumulated evapotranspiration rate has reached a value of 870 mm. As for cultivar Obatã, the maximum sucrose concentration was predicted with the same degree of accuracy using any of the parameters investigated. For the Obatã cultivar, the values of the variables calculated for the maximum sucrose concentration to be reached were 249 DAF, 3,090 GDD, 1,020 ETo and 900 ETr.

The impact of nano-coating on surface charge accumulation of epoxy resin insulator: characteristic and mechanism

NASA Astrophysics Data System (ADS)

Qi, Bo; Gao, Chunjia; Lv, Yuzhen; Li, Chengrong; Tu, Youping; Xiong, Jun

2018-06-01

The flashover phenomenon of the insulator is the main cause for insulating failure of GIS/GIL, and one of the most critical impacting factors is the accumulation of surface charge. The common methods to restrain the surface charge accumulation are reviewed in this paper. Through the reasonable comparison and analysis of these methods, nano-coatings for the insulator were selected as a way to restrain the surface charge accumulation. Based on this, six nano-coated epoxy resin samples with different concentrations of P25-TiO2 nanoparticles were produced. A high precision 3D surface charge measurement system was developed in this paper with a spatial resolution of 4.0 mm2 and a charge resolution of 0.01 µC (m2 · mV)‑1. The experimental results for the epoxy resin sample showed that with the concentration of nanoparticles of the coating material increasing, the surface charge density tended to first decrease and then increase. In the sample coated with 0.5% concentration of nanoparticles, the suppression effect is the optimum, leading to a 63.8% reduction of charge density under DC voltage. The application test for actual nano-coated GIS/GIL basin insulator indicated that the maximum suppression degree for the charge density under DC voltage could reach 48.3%, while it could reach 22.2% for switching impulse voltage and 12.5% for AC context. The control mechanism of nano-coatings on charge accumulation was proposed based on the analysis for surface morphology features and traps characteristics; the shallow traps dominate in the migration of charges while the deep traps operate on the charge accumulation. With the concentration of nanoparticles in nano-coating material mounting up, the density of shallow traps continuously increases, while for deep traps, it first decreases and then increases. For the sample with 0.5% concentration of nanoparticles coated, the competition between shallow traps and deep traps comes to the most balanced state, producing the most significant suppression impact on surface charge accumulation.

Electrostatic vibration energy harvester with 2.4-GHz Cockcroft-Walton rectenna start-up

NASA Astrophysics Data System (ADS)

Takhedmit, Hakim; Saddi, Zied; Karami, Armine; Basset, Philippe; Cirio, Laurent

2017-02-01

In this paper, we propose the design, fabrication and experiments of a macro-scale electrostatic vibration energy harvester (e-VEH), pre-charged wirelessly for the first time with a 2.4-GHz Cockcroft-Walton rectenna. The rectenna is designed and optimized to operate at low power densities and provide high voltage levels: 0.5 V at 0.76 μW/cm2 and 1 V at 1.53 μW/cm2. The e-VEH uses a Bennet doubler as a conditioning circuit. Experiments show a 23-V voltage across the transducer terminal, when the harvester is excited at 25 Hz by 1.5 g of external acceleration. An accumulated energy of 275 μJ and a maximum available power of 0.4 μW are achieved. xml:lang="fr"

Electrostatic Vibration Energy Harvester Pre-charged Wirelessly at 2.45 GHz

NASA Astrophysics Data System (ADS)

Saddi, Z.; Takhedmit, H.; Karami, A.; Basset, P.; Cirio, L.

2016-11-01

This paper reports the design, fabrication and experiments of an electrostatic vibration harvester (e-VEH), pre-charged wirelessly for the first time by using an electromagnetic waves harvester at 2.4 GHz. The rectenna uses the Cockcroft-Walton voltage doubler rectifier. It is designed and optimized to operate at low power densities and provides high voltage levels: 0.5 V at 0.5 μW/cm2 and 0.8 V at 1 μW/cm2 The e-VEH uses the Bennet doubler as conditioning circuit. Experiments show 23 V voltage across the transducer terminal when the harvester is excited at 25 Hz by 1.5 g of external acceleration. An accumulated energy of 275 μJ and a maximum power of 0.4 μW are available for the load.

Optimization of tannase production by Aureobasidium pullulans DBS66.

PubMed

Banerjee, Debdulal; Pati, Bikas R

2007-06-01

Tannase production by Aureobasidium pullulans DBS66 was optimized. The organism produced maximum tannase in the presence of 1% tannic acid after 36 h. Maximum gallic acid accumulation was observed within 36 h and tannic acid in the fermented broth was completely degraded after 42 h of growth. Glucose had a stimulatory effect on tannase synthesis at 0.1% (w/v) concentration. The organism showed maximum tannase production with (NH4)2HPO4 as nitrogen source. Shaking speed of 120 rpm and 50-ml broth volume have been found to be suitable for maximum tannase production.

Annual Changes in Forst Floor Weights Under a Southeast Missouri Oak Stand

Treesearch

Robert M. Loomis

1975-01-01

Amount of organic matter on the forest floor under a typical southeast Missouri oak stand varies about 2.1 tons/acre from season of greatest to season to least accumulation. This also corresponds to the amount of annual litter fall. Maximum accumulation of 7.5 tons/acre occured in Novermber after leaf-fall. Summer decomposition is rapid; minimumof 5.4 tons/acre was...

[Effects of drought and waterlogging on carbohydrate contents of cotton boll and its relationship with boll biomass accumulation at the flowering and bolling stage].

PubMed

Yang, Chang-Qin; Liu, Jing-Ran; Zhang, Guo-Wei; Liu, Rui-Xian; Zhou, Zhi-Guo

2014-08-01

Cotton cultivar NuCOTN 33B was planted in isolated pools treated with drought or waterlogging for 7 or 14 d to explore their effects on cotton boll carbohydrate content and its relationship with the biomass accumulation. The results showed that the drought treatment reduced the carbohydrate content of cotton boll shell on middle fruit branches, but had a weak effect on cotton boll shells on lower fruit branches. Soluble sugar, starch and sucrose contents of cotton boll shell on upper fruit branches under the drought condition and on whole plant branches under waterlogging treatment changed similarly, namely, the soluble sugar and starch content increased, while the sucrose content went down firstly and then increased later, which indicated that the exportation of sucrose from boll shell was inhibited and became worse with the increase of waterlogging duration. Compared with the boll shell, the carbohydrate contents of cotton seed were less affected by the drought and waterlogging treatments at the flowering and bolling stage. Under the treatments of drought and 7 d-waterlogging, the biomass accumulation of cotton bolls on the middle fruit branches initiated earlier but lasted less days, and the maximum speed at lower and upper fruit branches reduced, while the treatment of waterlogging for 14 d caused the decline of maximum speed of biomass accumulation of bolls on whole branches. On the other side, the correlation analysis showed the significant positive relationships among the boll biomass, the maximum speed and the contents of soluble sugar and sucrose in the boll shell respectively. In conclusion, the treatment of drought and waterlogging at the flowering and bolling stage retarded the outward transportation of sucrose from cotton bolls, changed the boll biomass accumulation characteristics, and therefore were detected as the important cause of cotton boll total biomass reduction.

Performance of integrated bioelectrochemical membrane reactor: Energy recovery, pollutant removal and membrane fouling alleviation

NASA Astrophysics Data System (ADS)

Dong, Yue; He, Weihua; Li, Chao; Liang, Dandan; Qu, Youpeng; Han, Xiaoyu; Feng, Yujie

2018-04-01

A novel hybrid bioelectrochemical membrane reactor with integrated microfiltration membrane as the separator between electrodes is developed for domestic wastewater treatment. After accumulation of biofilm, the organic pollutants are mainly degraded in anodic compartment, and microfiltration membrane blocks the adverse leakage of dissolved oxygen from aerated cathodic compartment. The maximum system power output is restricted by gas-water ratio following a Monod-like relationship. Within the tested gas-water ratios ranging from 0.6 to 42.9, the half-saturation constant (KQ) is 5.9 ± 0.9 with a theoretic maximum power density of 20.4 ± 1.0 W m-3. Energy balance analysis indicates an appropriate gas-water ratio regulation (from 2.3 to 28.6) for cathodic compartment is necessary to obtain positive energy output for the system. A maximum net electricity output is 9.09 × 10-3 kWh m-3 with gas-water ratio of 17.1. Notably, the system achieves the chemical oxygen demand removal of 98.3 ± 0.3%, ammonia nitrogen removal of 99.6 ± 0.1%, and total nitrogen removal of 80.0 ± 0.9%. This work verifies an effective integration of microfiltration membrane into bioelectrochemical system as separator for high-quality effluent and provides an insight into the operation and regulation of biocathode system for effective electrical energy output.

Characteristics of the overflow pollution of storm drains with inappropriate sewage entry.

PubMed

Yin, Hailong; Lu, Yi; Xu, Zuxin; Li, Huaizheng; Schwegler, Benedict R

2017-02-01

To probe the overflow pollution of separate storm drains with inappropriate sewage entries, in terms of the relationship between sewage entries and the corresponding dry-weather and wet-weather overflow, the monitoring activities were conducted in a storm drainage system in the Shanghai downtown area (374 ha). In this study site, samples from inappropriately entered dry-weather sewage and the overflow due to storm pumps operation on dry-weather and wet-weather days were collected and then monitored for six water quality constituents. It was found that overflow concentrations of dry-weather period could be higher than those of wet-weather period; under wet-weather period, the overflow concentrations of storm drains were close to or even higher than that of combined sewers. Relatively strong first flush mostly occurred under heavy rain that satisfied critical rainfall amount, maximum rainfall intensity, and maximum pumping discharge, while almost no first flush effect or only weak first flush effect was found for the other rainfall events. Such phenomenon was attributed to lower in-line pipe storage as compared to that of the combined sewers, and serious sediment accumulation within the storm pipes due to sewage entry. For this kind of system, treating a continuous overflow rate is a better strategy than treating the maximum amount of early part of the overflow. Correcting the key inappropriate sewage entries into storm drains should also be focused.

Optimization of soluble organic selenium accumulation during fermentation of Flammulina velutipes mycelia.

PubMed

Ma, Yunfeng; Xiang, Fu; Xiang, Jun; Yu, Longjiang

2012-01-01

Selenium is an essential nutrient with diverse physiological functions, and soluble organic selenium (SOS) sources have a higher bioavailability than inorganic selenium sources. Based on the response surface methodology and central composite design, this study presents the optimal medium components for SOS accumulation in batch cultures of Flammulina velutipes, i.e. 30 g/L glucose, 11.2 mg/L sodium selenite, and 1.85 g/L NH4NO3. Furthermore, logistic function model feeding was found to be the optimal feeding strategy for SOS accumulation during Flammulina velutipes mycelia fermentation, where the maximum SOS accumulation reached (4.63 +/- 0.24) mg/L, which is consistent with the predicted value.

Protecting Astronaut Health at First Entry into Vehicles Visiting the international Space Station: Insights from Whole-Module Offgas Testing

NASA Technical Reports Server (NTRS)

Meyers, Valerie

2014-01-01

NASA has accumulated considerable experience in offgas testing of whole modules prior to their docking with the International Space Station (ISS). Since 1998, the Space Toxicology Office has performed offgas testing of the Lab module, both MPLM modules, US Airlock, Node 1, Node 2, Node 3, ATV1, HTV1, and three commercial vehicles. The goal of these tests is twofold: first, to protect the crew from adverse health effects of accumulated volatile pollutants when they first enter the module on orbit, and secondly, to determine the additional pollutant load that the ISS air revitalization systems must handle. In order to predict the amount of accumulated pollutants, the module is sealed for at least 1/5th the worst-case time interval that could occur between the last clean air purge and final hatch closure on the ground and the crew's first entry on orbit. This time can range from a few days to a few months. Typically, triplicate samples are taken at pre-planned times throughout the test. Samples are then analyzed by gas chromatography and mass spectrometry, and the rate of accumulation of pollutants is then extrapolated over time. The analytical values are indexed against 7-day spacecraft maximum allowable concentrations (SMACs) to provide a prediction of the total toxicity value (T-value) at the time of first entry. This T-value and the toxicological effects of specific pollutants that contribute most to the overall toxicity are then used to guide first entry operations. Finally, results are compared to first entry samples collected on orbit to determine the predictive ability of the ground-based offgas test.

Do UV-A radiation and blue light during growth prime leaves to cope with acute high-light in photoreceptor mutants of Arabidopsis thaliana?

PubMed

Brelsford, Craig C; Morales, Luis O; Nezval, Jakub; Kotilainen, Titta K; Hartikainen, Saara M; Aphalo, Pedro J; Robson, T Matthew

2018-04-28

We studied how plants acclimated to growing conditions that included combinations of blue light and ultraviolet-A (UV-A) radiation, and whether their growing environment affected their photosynthetic capacity during and after a brief period of acute high light (as might happen during an under-canopy sunfleck). Arabidopsis thaliana Landsberg erecta wild-type were compared with mutants lacking functional blue-light-and-UV photoreceptors: phototropin 1PHOT1, cryptochromes (CRY1 and CRY2) and UV RESISTANT LOCUS 8 (uvr8). This was achieved using LED lamps in a controlled environment to create treatments with or without blue light, in a split-plot design with or without UV-A radiation. We compared the accumulation of phenolic compounds under growth conditions and after exposure to 30 minutes of high light at the end of the experiment (46 days), and likewise measured the operational efficiency of photosystem II (φPSII a proxy for photosynthetic performance) and dark-adapted maximum quantum yield (F v /F m to assess PSII damage). Our results indicate that cryptochromes are the main photoreceptors regulating phenolic-compound accumulation in response to blue light and UV-A radiation, and a lack of functional cryptochromes impairs photosynthetic performance under high light. Our findings also reveal a role for UVR8 in accumulating flavonoids in response to a low UV-A dose. Interestingly, phototropin 1 partially-mediated constitutive accumulation of phenolic compounds in the absence of blue light. Low irradiance blue light and UV-A did not improve φPSII and F v /F m upon our acute high light treatment, however CRYs played an important role in ameliorating high-light stress. This article is protected by copyright. All rights reserved.

High speed hydraulically-actuated operating system for an electric circuit breaker

DOEpatents

Iman, I.

1983-06-07

This hydraulically-actuated operating system comprises a cylinder, a piston movable therein in an opening direction to open a circuit breaker, and an accumulator for supplying pressurized liquid to a breaker-opening piston-actuating space within the cylinder. A normally-closed valve between the accumulator and the actuating space is openable to allow pressurized liquid from the accumulator to flow through the valve into the actuating space to drive the piston in an opening direction. A dashpotting mechanism operating separately from the hydraulic actuating system is provided, thereby reducing flow restriction interference with breaker opening. 3 figs.

High speed hydraulically-actuated operating system for an electric circuit breaker

DOEpatents

Iman, Imdad

1983-06-07

This hydraulically-actuated operating system comprises a cylinder, a piston movable therein in an opening direction to open a circuit breaker, and an accumulator for supplying pressurized liquid to a breaker-opening piston-actuating space within the cylinder. A normally-closed valve between the accumulator and the actuating space is openable to allow pressurized liquid from the accumulator to flow through the valve into the actuating space to drive the piston in an opening direction. A dashpotting mechanism operating separately from the hydraulic actuating system is provided, thereby reducing flow restriction interference with breaker opening.

A Low Power Linear Phase Programmable Long Delay Circuit.

PubMed

Rodriguez-Villegas, Esther; Logesparan, Lojini; Casson, Alexander J

2014-06-01

A novel linear phase programmable delay is being proposed and implemented in a 0.35 μm CMOS process. The delay line consists of N cascaded cells, each of which delays the input signal by Td/N, where Td is the total line delay. The delay generated by each cell is programmable by changing a clock frequency and is also fully independent of the frequency of the input signal. The total delay hence depends only on the chosen clock frequency and the total number of cascaded cells. The minimum clock frequency is limited by the maximum time a voltage signal can effectively be held by an individual cell. The maximum number of cascaded cells will be limited by the effects of accumulated offset due to transistor mismatch, which eventually will affect the operating mode of the individual transistors in a cell. This latter limitation has however been dealt with in the topology by having an offset compensation mechanism that makes possible having a large number of cascaded cells and hence a long resulting delay. The delay line has been designed for scalp-based neural activity analysis that is predominantly in the sub-100 Hz frequency range. For these signals, the delay generated by a 31-cell cascade has been demonstrated to be programmable from 30 ms to 3 s. Measurement results demonstrate a 31 stage, 50 Hz bandwidth, 0.3 s delay that operates from a 1.1 V supply with power consumption of 270 nW.

Enhancing wastewater reuse by forward osmosis with self-diluted commercial fertilizers as draw solutes.

PubMed

Zou, Shiqiang; He, Zhen

2016-08-01

Using fertilizers as draw solutes in forward osmosis (FO) can accomplish wastewater reuse with elimination of recycling draw solute. In this study, three commercial fast-release all-purpose solid fertilizers (F1, F2 and F3) were examined as draw solutes in a submerged FO system for water extraction from either deionized (DI) water or the treated wastewater. Systematic optimizations were conducted to enhance water extraction performance, including operation modes, initial draw concentrations and in-situ chemical fouling control. In the mode of the active layer facing the feed (AL-F or FO), a maximum of 324 mL water was harvested using 1-M F1, which provided 41% of the water need for fertilizer dilution for irrigation. Among the three fertilizers, F1 containing a lower urea content was the most favored because of a higher water extraction and a lower reverse solute flux (RSF) of major nutrients. Using the treated wastewater as a feed solution resulted in a comparable water extraction performance (317 mL) to that of DI water in 72 h and a maximum water flux of 4.2 LMH. Phosphorus accumulation on the feed side was mainly due to the FO membrane solute rejection while total nitrogen and potassium accumulation was mainly due to RSF from the draw solute. Reducing recirculation intensity from 100 to 10 mL min(-1) did not obviously decrease water flux but significantly reduced the energy consumption from 1.86 to 0.02 kWh m(-3). These results have demonstrated the feasibility of using commercial solid fertilizers as draw solutes for extracting reusable water from wastewater, and challenges such as reverse solute flux will need to be further addressed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Research on the resurrection evolution mechanism of Gendakan ancient landslide in the upstream on Lancang River, China

NASA Astrophysics Data System (ADS)

H, D.

2017-12-01

The Gendakan ancient landslide is located on the West bank of the upstream on Lancang River and about 4 km downstream from the Gushui hydropower station dam site. The ancient landslide is 850 m long and 700 m wide, the drill cores show that the maximum thickness of the landslide body is 107 m, with a mean thickness of approximately 80 m. Thus, the overall volume is about 3000×104m3. At present, the landslide has obvious deformation and failure signs, the leading edge is collapsing step by step. Once the landslide is unstable, it will affect the construction and operation of the Gushui hydropower station. In this paper, the development characteristics of the landslide accumulation body and the characteristics of the resurrection deformation are summarized in detail from the regional geological environment of the Gandakan landslide accumulation body. The three-dimensional geological model is established to analyze the stress and strain, displacement change and deformation failure characteristics and further evaluate its resurrection evolution trend , Combined with the developmental characteristics of the typical rock mass in the nearshore slope of the engineering area, analyzes the process of the resurrection and evolution of the rooted landslide accumulation. The FLAC-3D finite difference software was used to analyze the shear strain increment, displacement and plastic zone of the landslide accumulation body under natural conditions and rainfall conditions. The results show: the Gendakan landslide is stable in the natural state, and its deformation and failure are mainly caused by the tensile and shearing of the surface, under the rainfall condition, the local deformation and failure of the landslide accumulation body is obvious and the resurrection deformation Intensified. The resurrection evolutionary process of Gendakan ancient landslide includes three steps below. 1) The landslide body trailing edge creep cracking, leading edge shear deformation. 2) Sliding surface, accelerate the decline. 3)Disintegration of collision and impact into the dam.

Dynamics of nitrogen in subtropical wetland and its uptake and storage by Pistia stratiotes.

PubMed

Irfan, Sufia; Shardendu

2009-11-01

The paper describes the dynamics of nitrogen in different components (water, soil and plants) of Kabar wetland situated in Begusarai district of Bihar. Contents of nitrogen in the natural components were determined and were compared with the rate of uptake and accumulation under the experimental conditions. Physico-chemical characteristics of natural water and of test basins were quite similar. The trend of seasonal variation of NO3(-)-N in water and total N in soil and P. stratiotes tissue was almost similar but content of nitrogen differed significantly in the different components. The accumulation of nitrogen in the tissues of P. stratiotes was 5 to 15 fold higher than the concentration of nitrogen in the water and 2 to 3 fold higher than the nitrogen content measured in the soil. Maximum accumulation of nitrogen in P. stratiotes was 15.25 mg g(-1) when the concentration of NO3(-)-N in water was 0.86 mg l(-1). Under experimental conditions six different nitrogen concentrations were supplied and determined the uptake and accumulation of nitrogen in P. stratiotes. Maximum uptake and accumulation was 82.87 g m(-2) at the end of 60 days after starting the experiment but still the rate of accumulation was in rising trend. In another part of experiment no nitrogen was left in the basins of low concentrations (0.5 and 5 mg N l(-1)) at the end of 60 days of experiment but at higher concentrations (50 and 65 mg N l(-1)) significant amount of N was left in the test basin. The biomass enhancement was parallel with nitrogen supply till 15 mg N l(-1). This was opposite to the relationship between the nitrogen accumulation in the tissues and nitrogen supply in the experimental basins. Though, potassium was added as an essential growth nutrient but its accumulation was 95g m(-2) at 5 mg l(-1).

D-PSA-K: A Model for Estimating the Accumulated Potential Damage on Kiwifruit Canes Caused by Bacterial Canker during the Growing and Overwintering Seasons.

PubMed

Do, Ki Seok; Chung, Bong Nam; Joa, Jae Ho

2016-12-01

We developed a model, termed D-PSA-K, to estimate the accumulated potential damage on kiwifruit canes caused by bacterial canker during the growing and overwintering seasons. The model consisted of three parts including estimation of the amount of necrotic lesion in a non-frozen environment, the rate of necrosis increase in a freezing environment during the overwintering season, and the amount of necrotic lesion on kiwifruit canes caused by bacterial canker during the overwintering and growing seasons. We evaluated the model's accuracy by comparing the observed maximum disease incidence on kiwifruit canes against the damage estimated using weather and disease data collected at Wando during 1994-1997 and at Seogwipo during 2014-2015. For the Hayward cultivar, D-PSA-K estimated the accumulated damage as approximately nine times the observed maximum disease incidence. For the Hort16A cultivar, the accumulated damage estimated by D-PSA-K was high when the observed disease incidence was high. D-PSA-K could assist kiwifruit growers in selecting optimal sites for kiwifruit cultivation and establishing improved production plans by predicting the loss in kiwifruit production due to bacterial canker, using past weather or future climate change data.

Hydraulically-activated operating system for an electric circuit breaker

DOEpatents

Imam, Imdad; Barkan, Philip

1979-01-01

This operating system comprises a fluid motor having a piston, a breaker-opening space at one side of the piston, and a breaker-closing space at its opposite side. An accumulator freely communicates with the breaker-opening space for supplying pressurized fluid thereto during a circuit-breaker opening operation. A normally-closed valve located on the breaker-closing-side of the piston is openable to release liquid from the breaker-closing space so that pressurized liquid in the breaker-opening space can drive the piston in an opening direction. Means is provided for restoring the valve to its closed position following the circuit-breaker opening operation. An impeded passage affords communication between the accumulator and the breaker-closing space to allow pressurized liquid to flow from the accumulator to the breaker-closing space and develop a pressure therein substantially equal to accumulator pressure when the valve is restored to closed position following breaker-opening. This passage is so impeded that the flow therethrough from the accumulator into the breaker-closing space is sufficiently low during initial opening motion of the piston through a substantial portion of its opening stroke as to avoid interference with said initial opening motion of the piston.

Polyhydroxyalkanoates (PHA) production using wastewater as carbon source and activated sludge as microorganisms.

PubMed

Yan, S; Tyagi, R D; Surampalli, R Y

2006-01-01

Activated sludge from different full-scale wastewater treatment plants (municipal, pulp and paper industry, starch manufacturing and cheese manufacturing wastewaters) was used as a source of microorganisms to produce biodegradable plastics in shake flask experiments. Acetate, glucose and different wastewaters were used as carbon sources. Pulp and paper wastewater sludge was found to accumulate maximum concentration (43% of dry weight of suspended solids) of polyhydroxy alkanoates (PHA) with acetate as carbon source. Among the different wastewaters tested as a source of carbon, pulp and paper industry and starch industry wastewaters were found to be the best source of carbon while employing pulp and paper activated sludge for maximum accumulation of PHA. High concentration of volatile fatty acids in these wastewaters was the probable reason.

Time-dependent constitutive modeling of drive belts—II. The effect of the shape of material retardation spectrum on the strain accumulation process

NASA Astrophysics Data System (ADS)

Zupančič, B.; Emri, I.

2009-11-01

This is the second paper in the series addressing the constitutive modeling of dynamically loaded elastomeric products such as power transmission belts. During the normal operation of such belts certain segments of the belt structure are loaded via tooth-like cyclical loading. When the time-dependent properties of the elastomeric material “match” the time-scale of the dynamic loading a strain accumulation (incrementation) process occurs. It was shown that the location of a critical rotation speed strongly depends on the distribution (shape) of the retardation spectrum, whereas the magnitude of the accumulated strain is governed by the strength of the corresponding spectrum lines. These interrelations are extremely non-linear. The strain accumulation process is most intensive at the beginning of the drive belt operation, and is less intensive for longer belts. The strain accumulation process is governed by the spectrum lines that are positioned within a certain region, which we call the Strain Accumulation Window (SAW). An SAW is always located to the right of the spectrum line, L i , at log ( ω λ i )=0, where ω is the operational angular velocity. The width of the SAW depends on the width of the material spectrum. Based on the following analysis a new designing criterion is proposed for use in engineering applications for selecting a proper material for general drive-belt operations.

Application of a rotation system to oilseed rape and rice fields in Cd-contaminated agricultural land to ensure food safety.

PubMed

Yu, Lingling; Zhu, Junyan; Huang, Qingqing; Su, Dechun; Jiang, Rongfeng; Li, Huafen

2014-10-01

This field experiment analyzed the phytoremediation effects of oilseed rape in moderately cadmium (Cd)-contaminated farmland and the food safety of successive rice in an oilseed rape-rice rotation system. Two oilseed rape cultivars accumulated Cd at different rates. The rapeseed cultivar Zhucang Huazi exhibited high Cd accumulation rates, higher than the legal limit for human consumption (0.2mgkg(-1)); Cd concentrations in the cultivar Chuanyou II-93 were all below the maximum allowed level. Planting oilseed rape increased the uptake of Cd by the successive rice crop compared with a previous fallow treatment. Most Cd concentrations of brown rice were below the maximum allowed level. The phytoextraction efficiency was lower in the moderately Cd-contaminated soil in field experiments. The results suggest screening rice cultivars with lower Cd accumulation can assure the food safety; the mobilization of heavy metals by roots of different plant species should be considered during crop rotation to assure food safety. Copyright © 2014 Elsevier Inc. All rights reserved.

Activated sludge is a potential source for production of biodegradable plastics from wastewater.

PubMed

Khardenavis, A; Guha, P K; Kumar, M S; Mudliar, S N; Chakrabarti, T

2005-05-01

Increased utilization of synthetic plastics caused severe environmental pollution due to their non-biodegradable nature. In the search for environmentally friendly materials to substitute for conventional plastics, different biodegradable plastics have been developed by microbial fermentations. However, limitations of these materials still exist due to high cost. This study aims at minimization of cost for the production of biodegradable plastics P(3HB) and minimization of environmental pollution. The waste biological sludge generated at wastewater treatment plants is used for the production of P(3HB) and wastewater is used as carbon source. Activated sludge was induced by controlling the carbon: nitrogen ratio to accumulate storage polymer. Initially polymer accumulation was studied by using different carbon and nitrogen sources. Maximum accumulation of polymer was observed with carbon source acetic acid and diammonium hydrogen phosphate (DAHP) as nitrogen source. Further studies were carried out to optimize the carbon: nitrogen ratios using acetic acid and DAHP. A maximum of 65.84% (w/w) P(3HB) production was obtained at C/N ratio of 50 within 96 hours of incubation.

Bioaccumulation of Fe2O3(magnetic) nanoparticles in Ceriodaphnia dubia.

PubMed

Hu, Ji; Wang, Demin; Wang, Jiangtao; Wang, Jianmin

2012-03-01

While nano-Fe(2)O(3)(magnetic) is generally considered non-toxic, it could serve as a carrier of other toxic chemicals such as As(V) and enhance their toxicity. The bioaccumulation of nano-Fe(2)O(3)(m) with different exposure times, NP concentrations, and pH conditions was investigated using Ceriodaphnia dubia (C. dubia) as the model organism. Under natural pH conditions, C. dubia significantly accumulated nano-Fe(2)O(3)(m) in the gut, with the maximum accumulation being achieved after 6 h of exposure. The concentration of nano-Fe(2)O(3) also impacted its accumulation, with the maximum uptake occurring at 20 mg/L or more. In addition, the highest bioaccumulation occurred in a pH range of 7-8 where the highest feeding rate was reported, confirming that the ingestion of NPs is the main route of nano-Fe(2)O(3)(m) bioaccumulation. In a clean environment without NPs, depuration of nano-Fe(2)O(3)(m) occurred, and food addition accelerated the depuration process. Copyright © 2011 Elsevier Ltd. All rights reserved.

Effect of pH on growth and lipid accumulation kinetics of the microalga Chlorella vulgaris grown heterotrophically under sulfur limitation.

PubMed

Sakarika, Myrsini; Kornaros, Michael

2016-11-01

The goal of the present study was to investigate the pH range that can support the growth of C. vulgaris, and, more specifically, to identify the optimal pH for the microalga's growth, under heterotrophic conditions. Furthermore, the effect of pH on the accumulation of intracellular lipids was studied. A wide range of pH values was tested using the respective buffer solutions. The optimal pH for biomass growth and lipid accumulation under sulfur limitation was found to be 7.5, resulting in maximum specific growth rate of 0.541days(-1) and maximum total lipid content of 53.43%ggDW(-1). The fatty acid composition of C. vulgaris was found to be unrelated to pH, as the lipid content did not present significant variations in the pH values tested. The fatty acid profile was mainly composed of monounsaturated fatty acids (MUFAs) with the dominant one being oleic acid (C18:1). Copyright © 2016 Elsevier Ltd. All rights reserved.

Microbial conversion of synthetic and food waste-derived volatile fatty acids to lipids.

PubMed

Vajpeyi, Shashwat; Chandran, Kartik

2015-01-01

Lipid accumulation in the oleaginous yeast Cryptococcus albidus was evaluated using mixtures of volatile fatty acids (VFA) as substrates. In general, batch growth under nitrogen limitation led to higher lipid accumulation using synthetic VFA. During batch growth, an initial COD:N ratio of 25:1mg COD:mg N led to maximum intracellular lipid accumulation (28.3 ± 0.7% g/g dry cell weight), which is the maximum reported for C. albidus using VFA as the carbon source, without compromising growth kinetics. At this feed COD:N ratio, chemostat cultures fed with synthetic VFA yielded statistically similar intracellular lipid content as batch cultures (29.9 ± 1.9%, g/g). However, batch cultures fed with VFA produced from the fermentation of food waste, yielded a lower lipid content (14.9 ± 0.1%, g/g). The lipid composition obtained with synthetic and food-waste-derived VFA was similar to commercial biodiesel feedstock. We therefore demonstrate the feasibility of linking biochemical waste treatment and biofuel production using VFA as key intermediates. Copyright © 2015 Elsevier Ltd. All rights reserved.

Vinyl chloride removal from an air stream by biotrickling filter.

PubMed

Faraj, S H Esmaeili; Esfahany, M Nasr; Kadivar, M; Zilouei, H

2012-01-01

A biofiltration process was used for degradation of vinyl chloride as a hazardous material in the air stream. Three biotrickling filters in series-parallel allowing uniform feed and moisture distribution all over the bed were used. Granular activated carbon mixed with compost was employed as carrier bed. The biological culture consisted of mixture of activated sludge from PVC wastewater treatment plant. Concurrent flow of gas and liquid was used in the bed. Results indicated that during the operation period of 110 days, the biotrickling bed was able to remove over 35% of inlet vinyl chloride. Maximum elimination capacity was calculated to be 0.56 g.m(-3).hr(-1). The amount of chlorine accumulated in the circulating liquid due to the degradation of vinyl chloride was measured to be equal to the vinyl chloride removed from the air stream.

Results of a XIPS(copyrighted) 25-cm Thruster Discharge Cathode Wear Test

NASA Technical Reports Server (NTRS)

Polk, James E.; Goebel, Dan M.; Tighe, William

2009-01-01

The Xenon Ion Propulsion System (XIPS(c)) 25-cm thruster produced by L-3 Communications Electron Technologies, Inc. offers a number of potential benefits for planetary missions, including high efficiency and high Isp over a large power throttling range and availability from an active product line. The thruster is qualified for use on commercial communications satellites, which have requirements differing from those for typical planetary missions. In particular, deep space missions require longer service life over a broad range of throttling conditions. A XIPS (c) discharge cathode assembly was subjected to a long duration test to extend operating experience at the maximum power point and at throttled conditions unique to planetary mission applications. A total of 16079 hours were accumulated at conditions corresponding to the full power engine operating point at 4.2 kWe, an intermediate power point at 2.76 kWe and the minimum power point at 0.49 kWe. Minor performance losses and cathode keeper erosion were observed at the full power point, but there were no changes in performance and negligible erosion at the intermediate and minimum power points.

Ongoing Wear Test of a XIPS(c) 25-Centimeter Thruster Discharge Cathode

NASA Technical Reports Server (NTRS)

Polk, James E.; Goebel, Dan M.; Tighe, William

2008-01-01

The Xenon Ion Propulsion System (XIPS(c)) 25-cm thruster produced by L-3 Communications Electron Technologies, Inc. offers a number of potential benefits for planetary missions, including high efficiency and high Isp over a large power throttling range and availability from an active product line. The thruster is qualified for use on commercial communications satellites, which have requirements differing from those for typical planetary missions. In particular, deep space missions require longer service life over a broad range of throttling conditions. A XIPS(c) discharge cathode assembly is currently undergoing a long duration test to extend operating experience at the maximum power point and at throttled conditions unique to planetary mission applications. A total of 11080 hours have been accumulated at conditions corresponding to the full power engine operating point at 4.2 kWe and an intermediate power point at 2.76 kWe. Minor performance losses and cathode keeper erosion were observed at the full power point, but there were no changes in performance and negligible erosion at the intermediate power point.

High-potential accumulation and tolerance in the submerged hydrophyte Hydrilla verticillata (L.f.) Royle for nickel-contaminated water.

PubMed

Song, Yang; Zhang, Ling-Lei; Li, Jia; He, Xiao-Jia; Chen, Min; Deng, Yun

2018-06-18

Water contamination by nickel (Ni) has become an increasing concern in recent decades. Hydrilla verticillata (L.f.) Royle has been recognized as a promising accumulator of several potentially toxic elements (PTEs) in phytoremediation, but its Ni-accumulation characteristics and its mechanisms of tolerance to Ni remain largely unknown. This research investigated the biochemical responses of leaves and stems of H. verticillata to various concentrations of Ni (5, 10, 15, 20, and 40 μM) over periods of 7, 14, or 21 days. Plants accumulated considerable Ni to a maximum amount of 1080 mg kg -1 dry weight (DW) with a maximum bioconcentration factor of 1100; thus, high Ni accumulation was detected in H. verticillata. Low concentrations (5-15 μM) or short durations (less than 14 days) of Ni exposure might promote plant growth without adversely affecting normal metabolism. After peaking at day 14, a decline in bioaccumulation was unexpectedly observed as a long-term effect of Ni toxicity. Malondialdehyde content and the activities of defense-related enzymes changed in a similar pattern after treatment with Ni, increasing with both Ni concentration and exposure time to a peak (often at 5-15 μM on day 14), followed by a decline. Through a comprehensive analysis of all the test parameters, the tolerance thresholds were determined to be > 40.0 μM, 24.0 μM, and 15.8 μM at days 7, 14, and 21, respectively. Hydrilla verticillata could be a "high-potential accumulator" capable of decontaminating aquatic bodies polluted by Ni within the threshold range. Copyright © 2018 Elsevier Inc. All rights reserved.

Comparing the performance and operation stability of an SBR and MBBR for single-stage nitritation-anammox treating wastewater with high organic load.

PubMed

Lackner, Susanne; Horn, Harald

2013-01-01

Single stage nitritation-anammox reactors have gained increasing attention for their application in municipal and industrial wastewater treatment. The most commonly used system in municipal reject water treatment is at present the sequencing batch reactor (SBR), the moving-bed biofilm reactor (MBBR) is the second most common. However, little is known about their applicability to industrial wastewaters with high C/N ratios. This study presents a comparative approach to evaluate the performance of these two systems by changing the influent from reject water (C:N ratio 1:1) stepwise to an industrial wastewater (C:N ratio 3:1). An intentionally induced temperature drop that led to nitrite accumulation was also tested. The results showed that the MBBR (1.9 kg-N m(-3) d(-1)) was superior to the SBR (0.5 kg-N m(-3) d(-1)) with at maximum up to four times higher volumetric nitrogen removal rates. Both systems accumulated nitrite (> 100 mg-N L(-1)) during the temperature drop from 30 degrees C to as low as 18 degrees C (MBBR) and 20 degrees C (SBR), which subsequently resulted in almost complete loss in the removal capacities. However, the previous removal rates could be re-established in both systems within approximately 40 days. In comparison, the MBBR showed the more stable and higher performance even though higher nitrite concentrations (up to 500 mg-N L(-1)) were encountered. Overall, MBBR operation and handling was also easier and the system was more robust to disturbances compared to the SBR.

Effect of low air velocities on thermal homeostasis and comfort during exercise at space station operational temperature and humidity

NASA Technical Reports Server (NTRS)

Beumer, Ronald J.

1989-01-01

The effectiveness of different low air velocities in maintaining thermal comfort and homeostasis during exercise at space station operational temperature and humidity was investigated. Five male subjects exercised on a treadmill for successive ten minute periods at 60, 71, and 83 percent of maximum oxygen consumption at each of four air velocities, 30, 50, 80, and 120 ft/min, at 22 C and 62 percent relative humidity. No consistent trends or statistically significant differences between air velocities were found in body weight loss, sweat accumulation, or changes in rectal, skin, and body temperatures. Occurrence of the smallest body weight loss at 120 ft/min, the largest sweat accumulation at 30 ft/min, and the smallest rise in rectal temperature and the greatest drop in skin temperature at 120 ft/min all suggested more efficient evaporative cooling at the highest velocity. Heat storage at all velocities was evidenced by increased rectal and body temperatures; skin temperatures declined or increased only slightly. Body and rectal temperature increases corresponded with increased perception of warmth and slight thermal discomfort as exercise progressed. At all air velocities, mean thermal perception never exceeded warm and mean discomfort, greatest at 30 ft/min, was categorized at worst as uncomfortable; sensation of thermal neutrality and comfort returned rapidly after cessation of exercise. Suggestions for further elucidation of the effects of low air velocities on thermal comfort and homeostasis include larger numbers of subjects, more extensive skin temperature measurements and more rigorous analysis of the data from this study.

A Review of Cyanobacterial Odorous and Bioactive Metabolites: Impacts and Management Alternatives in Aquaculture

DTIC Science & Technology

2008-05-06

concentrations (i.e., basic conditions). Cyanobacteria are also well adapted to high-light and low-light conditions. Cyanobacteria benefit from photosynthetic...including the foot, gonads, or whole body of gastropods , the foot or whole body of Table 2 Maximum accumulation of cyanobacterial toxins in the tissues...Evidence suggests that gastropods , bivalves and crayfish provide a greater risk than fish to human consumers as they accumulate higher concentrations

Prospective application of Leucaena leucocephala for phytoextraction of Cd and Zn and nitrogen fixation in metal polluted soils.

PubMed

Saraswat, Shweta; Rai, J P N

2011-03-01

The study deals with phytoextraction of Zn and Cd by Leucaena leucocephala grown on effluent fed and low nitrogen soils collected from S1, S2, and S3 sites, representing decreasing metal content with increasing distance from the effluent drain. Plant nitrogen fixation potential and soil micro-biochemical attributes against metal stress were also assessed. Increasing soil metal content and plant growth enhanced metal accumulation. Relatively greater amount of Zn than Cd was accumulated by L. leucocephala, which exceeded in roots with that of other parts. Remediation factor for Cd was maximum (3.6%) in S2 grown plant. Nodule numbers, their biomass, nitrogenase activity, and leghaemoglobin content were maximum in plants grown in S3 and minimum in S1 soil having maximum metals. Maximum soil organic C, total N, C(mic), and N(mic), respiration rate, ATP content, and enzymatic activities in response to phytoremediation was recorded in S3 followed by S2 and S1. Phytoremediation for a year enhanced extractable Zn and Cd by 36% and 45%, and their total removal by 20% and 30%, respectively from S2, which suggests the possible application of L. leucocephala for the remediation of metal contaminated sites and their fertility restoration by improving microbial functionalities and N-pool.

Using multiple-accumulator CMACs to improve efficiency of the X part of an input-buffered FX correlator

NASA Astrophysics Data System (ADS)

Lapshev, Stepan; Hasan, S. M. Rezaul

2017-04-01

This paper presents the approach of using complex multiplier-accumulators (CMACs) with multiple accumulators to reduce the total number of memory operations in an input-buffered architecture for the X part of an FX correlator. A processing unit of this architecture uses an array of CMACs that are reused for different groups of baselines. The disadvantage of processing correlations in this way is that each input data sample has to be read multiple times from the memory because each input signal is used in many of these baseline groups. While a one-accumulator CMAC cannot switch to a different baseline until it is finished integrating the current one, a multiple-accumulator CMAC can. Thus, the array of multiple-accumulator CMACs can switch between processing different baselines that share some input signals at any moment to reuse the current data in the processing buffers. In this way significant reductions in the number of memory read operations are achieved with only a few accumulators per CMAC. For example, for a large number of input signals three-accumulator CMACs reduce the total number of memory operations by more than a third. Simulated energy measurements of four VLSI designs in a high-performance 28 nm CMOS technology are presented in this paper to demonstrate that using multiple accumulators can also lead to reduced power dissipation of the processing array. Using three accumulators as opposed to one has been found to reduce the overall energy of 8-bit CMACs by 1.4% through the reduction of the switching activity within their circuits, which is in addition to a more than 30% reduction in the memory.

36 CFR 3.15 - What is the maximum noise level for the operation of a vessel?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false What is the maximum noise... SERVICE, DEPARTMENT OF THE INTERIOR BOATING AND WATER USE ACTIVITIES § 3.15 What is the maximum noise level for the operation of a vessel? (a) A person may not operate a vessel at a noise level exceeding...

36 CFR 3.15 - What is the maximum noise level for the operation of a vessel?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false What is the maximum noise... SERVICE, DEPARTMENT OF THE INTERIOR BOATING AND WATER USE ACTIVITIES § 3.15 What is the maximum noise level for the operation of a vessel? (a) A person may not operate a vessel at a noise level exceeding...

Cost-effective data collection in Louisiana.

DOT National Transportation Integrated Search

2002-09-01

The purpose of this research was to identify cost-effective methods to accumulate data for metropolitan transportation planning in Louisiana. The research was directed at making maximum use of existing data sources, investigating the transferability ...

Production of biodegradable plastics from activated sludge generated from a food processing industrial wastewater treatment plant.

PubMed

Suresh Kumar, M; Mudliar, S N; Reddy, K M K; Chakrabarti, T

2004-12-01

Most of the excess sludge from a wastewater treatment plant (60%) is disposed by landfill. As a resource utilization of excess sludge, the production of biodegradable plastics using the sludge has been proposed. Storage polymers in bacterial cells can be extracted and used as biodegradable plastics. However, widespread applications have been limited by high production cost. In the present study, activated sludge bacteria in a conventional wastewater treatment system were induced, by controlling the carbon: nitrogen ratio to accumulate storage polymers. Polymer yield increased to a maximum 33% of biomass (w/w) when the C/N ratio was increased from 24 to 144, where as specific growth yield decreased with increasing C/N ratio. The conditions which are required for the maximum polymer accumulation were optimized and are discussed.

Sucrose-enhanced biosynthesis of medicinally important antioxidant secondary metabolites in cell suspension cultures of Artemisia absinthium L.

PubMed

Ali, Mohammad; Abbasi, Bilal Haider; Ahmad, Nisar; Ali, Syed Shujait; Ali, Shahid; Ali, Gul Shad

2016-12-01

Natural products are gaining tremendous importance in pharmaceutical industry and attention has been focused on the applications of in vitro technologies to enhance yield and productivity of such products. In this study, we investigated the accumulation of biomass and antioxidant secondary metabolites in response to different carbohydrate sources (sucrose, maltose, fructose and glucose) and sucrose concentrations (1, 3, 5, 7 and 9 %). Moreover, the effects of 3 % repeated sucrose feeding (day-12, -18 and -24) were also investigated. The results showed the superiority of disaccharides over monosaccharides for maximum biomass and secondary metabolites accumulation. Comparable profiles for maximum biomass were observed in response to sucrose and maltose and initial sucrose concentrations of 3 and 5 %. Maximum total phenolic and total flavonoid contents were displayed by cultures treated with sucrose and maltose; however, initial sucrose concentrations of 5 and 7 % were optimum for both classes of metabolites, respectively. Following 3 % extra sucrose feeding, cultures fed on day-24 (late-log phase) showed higher biomass, total phenolic and total flavonoid contents as compared to control cultures. Highest antioxidant activity was exhibited by maltose-treated cultures. Moreover, sucrose-treated cultures displayed positive correlation of antioxidant activity with total phenolics and total flavonoids production. This work describes the stimulatory role of disaccharides and sucrose feeding strategy for higher accumulation of phenolics and flavonoids, which could be potentially scaled up to bioreactor level for the bulk production of these metabolites in suspension cultures of A. absinthium.

Development of a model to select plants with optimum metal phytoextraction potential.

PubMed

Guala, Sebastián D; Vega, Flora A; Covelo, Emma F

2011-07-01

The aim of the present study is to propose a nonlinear model which provides an indicator for the maximum phytoextraction of metals to help in the decision-making process. Research into different species and strategies plays an important role in the application of phytoextraction techniques to the remediation of contaminated soil. Also, the convenience of species according to their biomass and pollutant accumulation capacities has gained important space in discussions regarding remediation strategies, whether to choose species with low accumulation capacities and high biomass or high accumulation capacities with low biomass. The effects of heavy metals in soil on plant growth are studied by means of a nonlinear interaction model which relates the dynamics of the uptake of heavy metals by plants to heavy metal deposed in soil. The model, presented theoretically, provides an indicator for the maximum phytoextraction of metals which depends on adjustable parameters of both the plant and the environmental conditions. Finally, in order to clarify its applicability, a series of experimental results found in the literature are presented to show how the model performs consistently with real data. The inhibition of plant growth due to heavy metal concentration can be predicted by a simple kinetic model. The model proposed in this study makes it possible to characterize the nonlinear behaviour of the soil-plant interaction with heavy metal pollution in order to establish maximum uptake values for heavy metals in the harvestable part of plants.

Effect of pulse electric fields (PEF) on accumulation of magnesium and zinc ions in Saccharomyces cerevisiae cells.

PubMed

Pankiewicz, Urszula; Sujka, Monika; Włodarczyk-Stasiak, Marzena; Mazurek, Artur; Jamroz, Jerzy

2014-08-15

Cultures of Saccharomyces cerevisiae were treated with PEF to improve simultaneous accumulation of magnesium and zinc ions in the biomass. The results showed that the ions concentration in the medium and their mutual interactions affect accumulation in cells. Increasing the concentration of one ion in the medium reduced the accumulation of the second one, in the control as well as in the cells treated with PEF. Under optimized conditions, that is, on 15 min exposure of the 20 h grown culture to PEF of 5.0 kV/cm and 20 μs pulse width, accumulation of magnesium and zinc in yeast biomass reached maximum levels of 2.85 and 11.41 mg/gd.m., respectively, To summarize, optimization of ion pair concentration and PEF parameters caused a 1.5 or 2-fold increase of magnesium and zinc accumulation, respectively, in S. cerevisiae. Copyright © 2014 Elsevier Ltd. All rights reserved.

Maximum likelihood decoding analysis of Accumulate-Repeat-Accumulate Codes

NASA Technical Reports Server (NTRS)

Abbasfar, Aliazam; Divsalar, Dariush; Yao, Kung

2004-01-01

Repeat-Accumulate (RA) codes are the simplest turbo-like codes that achieve good performance. However, they cannot compete with Turbo codes or low-density parity check codes (LDPC) as far as performance is concerned. The Accumulate Repeat Accumulate (ARA) codes, as a subclass of LDPC codes, are obtained by adding a pre-coder in front of RA codes with puncturing where an accumulator is chosen as a precoder. These codes not only are very simple, but also achieve excellent performance with iterative decoding. In this paper, the performance of these codes with (ML) decoding are analyzed and compared to random codes by very tight bounds. The weight distribution of some simple ARA codes is obtained, and through existing tightest bounds we have shown the ML SNR threshold of ARA codes approaches very closely to the performance of random codes. We have shown that the use of precoder improves the SNR threshold but interleaving gain remains unchanged with respect to RA code with puncturing.

Sludge accumulation pattern inside oxidation ditch case study.

PubMed

Fouad, Moharram; El-Morsy, Ahmed

2014-01-01

The sludge accumulation pattern of an oxidation ditch (OD) plant treating municipal wastewater was observed under dry and wet weather conditions, during 3 years of operation. The accumulation patterns along the ditches and their rates were revealed. In addition, the composition of the accumulation was investigated. Finally, the ratio of sand and volatile particles, mixed liquor suspended solids (MLSS), and mixed liquor volatile suspended solids, as well as the removal efficiency were also observed against the accumulated sludge. Further, a laboratory-scale channel was used to investigate the settleability of grit after mixing with variable values of MLSS. The observed results indicated that the economical design and operation of ODs using a velocity value between 0.3-0.35 m/s is not recommended, to avoid the settling of all solids. High values of MLSS and sludge age need high horizontal velocity (more than 0.35 m/s) and more power to avoid settling problems and system failure. The influence of flow velocity on the sludge settleability was studied, enabling better planning of future ditch design and operation.

Description and operation of Haakon School geothermal heating system

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

Childs, F.W.; Kirol, L.D.; Sanders, R.D.

1997-12-01

Haakon School is located in the city of Philip, near the Badlands National Park in the southwest quadrant of South Dakota. The town overlies the Madison Formation which is a large-area aquifer. The aquifer has a demonstrated capability to produce geothermal water. A system to tap this potential and heat the Haakon School District buildings in Philip has been in operation since November 1980. Five school buildings having a total area of 44,000 ft{sup 2} (4088 ft{sup 2}) are heated with 157{degrees}F (69{degrees}C) water. A single well provides water at a maximum artesian flow of 340 gpm (21.5 L/s), whichmore » more than meets the heat demand of the school buildings. Eight buildings in the Philip business district utilize geothermal fluid discharged from the school for space heating. During the 1980-81 heating season, these buildings obtained 75% to 90% of their heat from geothermal fluid. Peak heat delivery of the system is 5.5 million Btu/h (1.61. MJ/s), with an annual energy delivery of 9.5 billion Btu (10 TJ). The geothermal system has operated nearly problem free with the exception of the equipment to remove Radium-226 from the spent fluid. Barium chloride is added to the water to precipitate sulfates containing the radium. Accumulation of precipitates in piping has caused some operational problems.« less

Stripping Voltammetry

NASA Astrophysics Data System (ADS)

Lovrić, Milivoj

Electrochemical stripping means the oxidative or reductive removal of atoms, ions, or compounds from an electrode surface (or from the electrode body, as in the case of liquid mercury electrodes with dissolved metals) [1-5]. In general, these atoms, ions, or compounds have been preliminarily immobilized on the surface of an inert electrode (or within it) as the result of a preconcentration step, while the products of the electrochemical stripping will dissolve in the electrolytic solution. Often the product of the electrochemical stripping is identical to the analyte before the preconcentration. However, there are exemptions to these rules. Electroanalytical stripping methods comprise two steps: first, the accumulation of a dissolved analyte onto, or in, the working electrode, and, second, the subsequent stripping of the accumulated substance by a voltammetric [3, 5], potentiometric [6, 7], or coulometric [8] technique. In stripping voltammetry, the condition is that there are two independent linear relationships: the first one between the activity of accumulated substance and the concentration of analyte in the sample, and the second between the maximum stripping current and the accumulated substance activity. Hence, a cumulative linear relationship between the maximum response and the analyte concentration exists. However, the electrode capacity for the analyte accumulation is limited and the condition of linearity is satisfied only well below the electrode saturation. For this reason, stripping voltammetry is used mainly in trace analysis. The limit of detection depends on the factor of proportionality between the activity of the accumulated substance and the bulk concentration of the analyte. This factor is a constant in the case of a chemical accumulation, but for electrochemical accumulation it depends on the electrode potential. The factor of proportionality between the maximum stripping current and the analyte concentration is rarely known exactly. In fact, it is frequently ignored. For the analysis it suffices to establish the linear relationship empirically. The slope of this relationship may vary from one sample to another because of different influences of the matrix. In this case the concentration of the analyte is determined by the method of standard additions [1]. After measuring the response of the sample, the concentration of the analyte is deliberately increased by adding a certain volume of its standard solution. The response is measured again, and this procedure is repeated three or four times. The unknown concentration is determined by extrapolation of the regression line to the concentration axis [9]. However, in many analytical methods, the final measurement is performed in a standard matrix that allows the construction of a calibration plot. Still, the slope of this plot depends on the active area of the working electrode surface. Each solid electrode needs a separate calibration plot, and that plot must be checked from time to time because of possible deterioration of the electrode surface [2].

Evaluation of probable maximum snow accumulation: Development of a methodology for climate change studies

NASA Astrophysics Data System (ADS)

Klein, Iris M.; Rousseau, Alain N.; Frigon, Anne; Freudiger, Daphné; Gagnon, Patrick

2016-06-01

Probable maximum snow accumulation (PMSA) is one of the key variables used to estimate the spring probable maximum flood (PMF). A robust methodology for evaluating the PMSA is imperative so the ensuing spring PMF is a reasonable estimation. This is of particular importance in times of climate change (CC) since it is known that solid precipitation in Nordic landscapes will in all likelihood change over the next century. In this paper, a PMSA methodology based on simulated data from regional climate models is developed. Moisture maximization represents the core concept of the proposed methodology; precipitable water being the key variable. Results of stationarity tests indicate that CC will affect the monthly maximum precipitable water and, thus, the ensuing ratio to maximize important snowfall events. Therefore, a non-stationary approach is used to describe the monthly maximum precipitable water. Outputs from three simulations produced by the Canadian Regional Climate Model were used to give first estimates of potential PMSA changes for southern Quebec, Canada. A sensitivity analysis of the computed PMSA was performed with respect to the number of time-steps used (so-called snowstorm duration) and the threshold for a snowstorm to be maximized or not. The developed methodology is robust and a powerful tool to estimate the relative change of the PMSA. Absolute results are in the same order of magnitude as those obtained with the traditional method and observed data; but are also found to depend strongly on the climate projection used and show spatial variability.

Operational Status of the International Space Station Plasma Contactor Hollow Cathode Assemblies July 2001 to May 2013

NASA Technical Reports Server (NTRS)

Kamhawi, Hani; Yim, John T.; Patterson, Michael J.; Dalton, Penni J.

2013-01-01

The International Space Station has onboard two Aerojet Rocketdyne developed plasma contactor units that perform the function of charge control. The plasma contactor units contain NASA Glenn Research Center developed hollow cathode assemblies. NASA Glenn Research Center monitors the on-orbit operation of the flight hollow cathode assemblies. As of May 31, 2013, HCA.001-F has been ignited and operated 123 times and has accumulated 8072 hours of operation, whereas, HCA.003-F has been ignited and operated 112 times and has accumulated 9664 hours of operation. Monitored hollow cathode ignition times and anode voltage magnitudes indicate that they continue to operate nominally.

Operational Status of the International Space Station Plasma Contactor Hollow Cathode Assemblies from July 2011 to May 2013

NASA Technical Reports Server (NTRS)

Kamhawi, Hani; Yim, John T.; Patterson, Michael J.; Dalton, Penni J.

2014-01-01

The International Space Station has onboard two Aerojet Rocketdyne developed plasma contactor units that perform the function of charge control. The plasma contactor units contain NASA Glenn Research Center developed hollow cathode assemblies. NASA Glenn Research Center monitors the onorbit operation of the flight hollow cathode assemblies. As of May 31, 2013, HCA.001-F has been ignited and operated 123 times and has accumulated 8072 hours of operation, whereas, HCA.003-F has been ignited and operated 112 times and has accumulated 9664 hours of operation. Monitored hollow cathode ignition times and anode voltage magnitudes indicate that they continue to operate nominally.

Quantification of Pea enation mosaic virus 1 and 2 during infection of Pisum sativum by one step real-time RT-PCR.

PubMed

Doumayrou, Juliette; Sheber, Melissa; Bonning, Bryony C; Miller, W Allen

2017-02-01

Pea enation mosaic virus 1 (PEMV1) and Pea enation mosaic virus 2 (PEMV2) are two viruses in an obligate symbiosis that cause pea enation mosaic disease mainly in plants in the Fabaceae family. This virus system is a valuable model to investigate plant virus replication, movement and vector transmission. Thus, here we describe growth conditions, virus detection methods, and virus accumulation behavior. To measure the accumulation and movement of PEMV1 and PEMV2 in plants during the course of infection, we developed a quantitative real-time one-step reverse transcription PCR procedure using the SYBR-green ® technology. Viral primers were designed that anneal to conserved but distinct regions in the RNA-dependent RNA polymerase gene of each virus. Moreover, the normalization of viral accumulation was performed to correct for sample-to-sample variation by designing primers to two different Pisum sativum housekeeping genes: actin and β-tubulin. Transcript levels for these housekeeping genes did not change significantly in response to PEMV infection. Conditions were established for maximum PCR efficiency for each gene, and quantification using QuBit ® technology. Both viruses reached maximum accumulation around 21days post-inoculation of pea plants. These results provide valuable tools and knowledge to allow reproducible studies of this emerging model virus system virus complex. Copyright © 2016 Elsevier B.V. All rights reserved.

Maximum Relative Entropy of Coherence: An Operational Coherence Measure.

PubMed

Bu, Kaifeng; Singh, Uttam; Fei, Shao-Ming; Pati, Arun Kumar; Wu, Junde

2017-10-13

The operational characterization of quantum coherence is the cornerstone in the development of the resource theory of coherence. We introduce a new coherence quantifier based on maximum relative entropy. We prove that the maximum relative entropy of coherence is directly related to the maximum overlap with maximally coherent states under a particular class of operations, which provides an operational interpretation of the maximum relative entropy of coherence. Moreover, we show that, for any coherent state, there are examples of subchannel discrimination problems such that this coherent state allows for a higher probability of successfully discriminating subchannels than that of all incoherent states. This advantage of coherent states in subchannel discrimination can be exactly characterized by the maximum relative entropy of coherence. By introducing a suitable smooth maximum relative entropy of coherence, we prove that the smooth maximum relative entropy of coherence provides a lower bound of one-shot coherence cost, and the maximum relative entropy of coherence is equivalent to the relative entropy of coherence in the asymptotic limit. Similar to the maximum relative entropy of coherence, the minimum relative entropy of coherence has also been investigated. We show that the minimum relative entropy of coherence provides an upper bound of one-shot coherence distillation, and in the asymptotic limit the minimum relative entropy of coherence is equivalent to the relative entropy of coherence.

40 CFR Table 3 to Subpart Ec of... - Operating Parameters To Be Monitored and Minimum Measurement and Recording Frequencies

Code of Federal Regulations, 2014 CFR

2014-07-01

... filter Wet scrubber Dry scrubber followed by fabric filter and wet scrubber Maximum operating parameters: Maximum charge rate Continuous 1×hour ✔ ✔ ✔ Maximum fabric filter inlet temperature Continuous 1×minute...

40 CFR Table 3 to Subpart Ec of... - Operating Parameters To Be Monitored and Minimum Measurement and Recording Frequencies

Code of Federal Regulations, 2013 CFR

2013-07-01

... filter Wet scrubber Dry scrubber followed by fabric filter and wet scrubber Maximum operating parameters: Maximum charge rate Continuous 1×hour ✔ ✔ ✔ Maximum fabric filter inlet temperature Continuous 1×minute...

Unveiling characteristics of a bioelectrochemical system with polarity reversion for simultaneous azo dye treatment and bioelectricity generation.

PubMed

Sun, Jian; Zhang, Yaping; Liu, Guoguang; Ning, Xunan; Wang, Yujie; Liu, Jingyong

2015-09-01

A novel bioelectrochemical system (BES) operated with polarity reversion was explored for simultaneous anaerobic/aerobic treatment of azo dye and production of bioelectricity under extremely low buffer. The Congo red was first decolorized in anode, with completed color removal in 35 h. The resultant decolorization intermediates were then mineralized after the anode reversed to aerobic biocathode, evidenced by 55 % chemical oxygen demand (COD) removal in 200 h. The mineralization efficiency was further increased to 70 % when the period of the half-cycle was prolonged to 375 h. Meanwhile, the BES produced a continuous stable positive/negative alternate voltage output under 5 mM phosphate buffer because of the self-neutralization of the accumulated protons and hydroxyl ions in electrolyte. The electrode performance was significantly improved, which was indicated by alleviated electrode polarization, due to in situ use of accumulated protons and hydroxyl ions and enhanced electron transfer in the presence of Congo red and its degradation intermediates, which resulted in 1.05-fold increases in maximum power density (67.5 vs. 32.9 mW/m(2)). An analysis of the microbial diversity in the biofilm revealed that the biofilm was dominated by facultative bacteria with functional roles in contaminant degradation and electricity generation.

49 CFR 192.621 - Maximum allowable operating pressure: High-pressure distribution systems.

Code of Federal Regulations, 2012 CFR

2012-10-01

... STANDARDS Operations § 192.621 Maximum allowable operating pressure: High-pressure distribution systems. (a) No person may operate a segment of a high pressure distribution system at a pressure that exceeds the... segment of a distribution system otherwise designed to operate at over 60 p.s.i. (414 kPa) gage, unless...

49 CFR 192.621 - Maximum allowable operating pressure: High-pressure distribution systems.

Code of Federal Regulations, 2011 CFR

2011-10-01

... STANDARDS Operations § 192.621 Maximum allowable operating pressure: High-pressure distribution systems. (a) No person may operate a segment of a high pressure distribution system at a pressure that exceeds the... segment of a distribution system otherwise designed to operate at over 60 p.s.i. (414 kPa) gage, unless...

49 CFR 192.621 - Maximum allowable operating pressure: High-pressure distribution systems.

Code of Federal Regulations, 2010 CFR

2010-10-01

... STANDARDS Operations § 192.621 Maximum allowable operating pressure: High-pressure distribution systems. (a) No person may operate a segment of a high pressure distribution system at a pressure that exceeds the... segment of a distribution system otherwise designed to operate at over 60 p.s.i. (414 kPa) gage, unless...

49 CFR 192.621 - Maximum allowable operating pressure: High-pressure distribution systems.

Code of Federal Regulations, 2014 CFR

2014-10-01

... STANDARDS Operations § 192.621 Maximum allowable operating pressure: High-pressure distribution systems. (a) No person may operate a segment of a high pressure distribution system at a pressure that exceeds the... segment of a distribution system otherwise designed to operate at over 60 p.s.i. (414 kPa) gage, unless...

49 CFR 192.621 - Maximum allowable operating pressure: High-pressure distribution systems.

Code of Federal Regulations, 2013 CFR

2013-10-01

... STANDARDS Operations § 192.621 Maximum allowable operating pressure: High-pressure distribution systems. (a) No person may operate a segment of a high pressure distribution system at a pressure that exceeds the... segment of a distribution system otherwise designed to operate at over 60 p.s.i. (414 kPa) gage, unless...

Insights into the distribution of water in a self-humidifying H2/O2 proton-exchange membrane fuel cell using 1H NMR microscopy.

PubMed

Feindel, Kirk W; Bergens, Steven H; Wasylishen, Roderick E

2006-11-01

Proton ((1)H) NMR microscopy is used to investigate in-situ the distribution of water throughout a self-humidifying proton-exchange membrane fuel cell, PEMFC, operating at ambient temperature and pressure on dry H(2)(g) and O(2)(g). The results provide the first experimental images of the in-plane distribution of water within the PEM of a membrane electrode assembly in an operating fuel cell. The effect of gas flow configuration on the distribution of water in the PEM and cathode flow field is investigated, revealing that the counter-flow configurations yield a more uniform distribution of water throughout the PEM. The maximum power output from the PEMFC, while operating under conditions of constant external load, occurs when H(2)O(l) is first visible in the (1)H NMR image of the cathode flow field, and subsequently declines as this H(2)O(l) continues to accumulate. The (1)H NMR microscopy experiments are in qualitative agreement with predictions from several theoretical modeling studies (e.g., Pasaogullari, U.; Wang, C. Y. J. Electrochem. Soc. 2005, 152, A380-A390), suggesting that combined theoretical and experimental approaches will constitute a powerful tool for PEMFC design, diagnosis, and optimization.

Efficient production of mutant phytase (phyA-7) derived from Selenomonas ruminantium using recombinant Escherichia coli in pilot scale.

PubMed

Chi-Wei Lan, John; Chang, Chih-Kai; Wu, Ho-Shing

2014-09-01

A mutant gene of rumen phytase (phyA-7) was cloned into pET23b(+) vector and expressed in the Escherichia coli BL21 under the control of the T7 promoter. The study of fermentation conditions includes the temperature impacts of mutant phytase expression, the effect of carbon supplements over induction stage, the inferences of acetic acid accumulation upon enzyme expression and the comparison of one-stage and two-stage operations in batch mode. The maximum value of phytase activity was reached 107.0 U mL(-1) at induction temperature of 30°C. Yeast extract supplement demonstrated a significant increase on both protein concentration and phytase activity. The acetic acid (2 g L(-1)) presented in the modified synthetic medium demonstrated a significant decrease on expressed phytase activity. A two-stage batch operation enhanced the level of phytase activity from 306 to 1204 U mL(-1) in the 20 L of fermentation scale. An overall 3.7-fold improvement in phytase yield (35,375.72-1,31,617.50 U g(-1) DCW) was achieved in the two-stage operation. Copyright © 2014 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Underestimated effects of sediments on enhanced startup performance of biofilm systems for polluted source water pretreatment.

PubMed

Lv, Zheng-Hui; Wang, Jing; Yang, Guang-Feng; Feng, Li-Juan; Mu, Jun; Zhu, Liang; Xu, Xiang-Yang

2018-02-01

In order to evaluate the enhancement mechanisms of enhanced startup performance in biofilm systems for polluted source water pretreatment, three lab-scale reactors with elastic stereo media (ESM) were operated under different enhanced sediment and hydraulic agitation conditions. It is interesting to found the previously underestimated or overlooked effects of sediment on the enhancement of pollutants removal performance and enrichment of functional bacteria in biofilm systems. The maximum NH 4 + -N removal rate of 0.35 mg L -1 h -1 in sediment enhanced condition was 2.19 times of that in control reactor. Sediment contributed to 42.0-56.5% of NH 4 + -N removal and 15.4-41.2% of total nitrogen removal in different reactors under different operation conditions. The enhanced hydraulic agitation with sediment further improved the operation performance and accumulation of functional bacteria. Generally, Proteobacteria (48.9-52.1%), Bacteroidetes (18.9-20.8%) and Actinobacteria (15.7-18.5%) were dominant in both sediment and ESM bioiflm at  phylum level. The potentially functional bacteria found in sediment and ESM biofilm samples with some functional bacteria mainly presented in sediment samples only (e.g., Genera Bacillus and Lactococcus of Firmicutes phylum) may commonly contribute to the removal of nitrogen and organics.

Performance analysis for minimally nonlinear irreversible refrigerators at finite cooling power

NASA Astrophysics Data System (ADS)

Long, Rui; Liu, Zhichun; Liu, Wei

2018-04-01

The coefficient of performance (COP) for general refrigerators at finite cooling power have been systematically researched through the minimally nonlinear irreversible model, and its lower and upper bounds in different operating regions have been proposed. Under the tight coupling conditions, we have calculated the universal COP bounds under the χ figure of merit in different operating regions. When the refrigerator operates in the region with lower external flux, we obtained the general bounds (0 < ε <(√{ 9 + 8εC } - 3) / 2) under the χ figure of merit. We have also calculated the universal bounds for maximum gain in COP under different operating regions to give a further insight into the COP gain with the cooling power away from the maximum one. When the refrigerator operates in the region located between maximum cooling power and maximum COP with lower external flux, the upper bound for COP and the lower bound for relative gain in COP present large values, compared to a relative small loss from the maximum cooling power. If the cooling power is the main objective, it is desirable to operate the refrigerator at a slightly lower cooling power than at the maximum one, where a small loss in the cooling power induces a much larger COP enhancement.

ROAD MAP FOR DEVELOPMENT OF CRYSTAL-TOLERANT HIGH LEVEL WASTE GLASSES

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

Fox, K.; Peeler, D.; Herman, C.

The U.S. Department of Energy (DOE) is building a Tank Waste Treatment and Immobilization Plant (WTP) at the Hanford Site in Washington to remediate 55 million gallons of radioactive waste that is being temporarily stored in 177 underground tanks. Efforts are being made to increase the loading of Hanford tank wastes in glass while meeting melter lifetime expectancies and process, regulatory, and product quality requirements. This road map guides the research and development for formulation and processing of crystaltolerant glasses, identifying near- and long-term activities that need to be completed over the period from 2014 to 2019. The primary objectivemore » is to maximize waste loading for Hanford waste glasses without jeopardizing melter operation by crystal accumulation in the melter or melter discharge riser. The potential applicability to the Savannah River Site (SRS) Defense Waste Processing Facility (DWPF) will also be addressed in this road map. The planned research described in this road map is motivated by the potential for substantial economic benefits (significant reductions in glass volumes) that will be realized if the current constraints (T1% for WTP and TL for DWPF) are approached in an appropriate and technically defensible manner for defense waste and current melter designs. The basis of this alternative approach is an empirical model predicting the crystal accumulation in the WTP glass discharge riser and melter bottom as a function of glass composition, time, and temperature. When coupled with an associated operating limit (e.g., the maximum tolerable thickness of an accumulated layer of crystals), this model could then be integrated into the process control algorithms to formulate crystal-tolerant high-level waste (HLW) glasses targeting high waste loadings while still meeting process related limits and melter lifetime expectancies. The modeling effort will be an iterative process, where model form and a broader range of conditions, e.g., glass composition and temperature, will evolve as additional data on crystal accumulation are gathered. Model validation steps will be included to guide the development process and ensure the value of the effort (i.e., increased waste loading and waste throughput). A summary of the stages of the road map for developing the crystal-tolerant glass approach, their estimated durations, and deliverables is provided.« less

Presence of understory shrubs constrains carbon gain in sunflecks by advance-regeneration seedlings: evidence from Quercus Rubra seedling grouwing in understory forest patches with or without evergreen shrubs present

Treesearch

E.T. Nilsen; T.T. Lei; S.W. Semones

2009-01-01

We investigated whether dynamic photosynthesis of understory Quercus rubra L. (Fagaceae) seedlings can acclimate to the altered pattern of sunflecks in forest patches with Rhododendron maximum L. (Ericaceae), an understory evergreen shrub. Maximum photosynthesis (A) and total CO2 accumulated during lightflecks was greatest for 400-s lightflecks, intermediate for 150-s...

Marine Export Production and Remineralization During Early Eocene Hyperthermal Events at ODP Site 1263, Walvis Ridge, ODP Site 1209, Shatsky Rise and ODP Site 1215, Equatorial Pacific Ocean

NASA Astrophysics Data System (ADS)

Lewis, A.; Griffith, E. M.; Thomas, E.; Winguth, A. M. E.

2017-12-01

Understanding the impacts of global hyperthermal events on marine productivity and remineralization is important for understanding the reaction of the ocean to major climate change. Marine export production and remineralization was reconstructed using marine (pelagic) barite accumulation rates (BAR) coupled with records of benthic foraminiferal assemblages across the Paleocene - Eocene Thermal Maximum (PETM) at 55.3 Ma, Eocene Thermal Maximum 2 (ETM2) 2 Ma later, and ETM3 3.1 Ma after the PETM. Marine barite accumulates in deep sea sediment precipitating in the overlying water column during degradation of organic matter exported from the photic zone. Foraminiferal data indicate the amount of organic matter reaching the seafloor. We use the difference between these records to infer changes in rates of remineralization. We present data from ODP Site on Walvis Ridge, Southeastern Atlantic; ODP Site 1209 on Shatsky Rise, North Pacific; and ODP Site 1215, equatorial Pacific. Sites 1263 and 1215 had maximum BAR roughly centered over the maximum negative PETM CIE, whereas at Site 1209 the maximum was before the PETM. The maximum BAR across ETM2 and ETM3 (0.5 and 0.25 of that at the PETM, respectively) was centered over the maximum negative CIE at Site 1263. At Site 1209, the BAR (0.5 the maximum value before the PETM) peaked before ETM2. Barite concentration at Site 1215 was low across at the smaller hyperthermals, but the onset of ETM2 had a maximum value < 3% of the PETM, whereas the ETM3 maximum occurred during the CIE recovery and was < 10% of ETM2. Benthic foraminiferal data indicate decreased food arrival at the seafloor during elevated BAR, thus indicating enhanced remineralization. During the PETM, at all 3 sites, increases in barite coincided with reduced BFAR. Similar trends were observed during ETM2 at Sites 1263 and 1215, suggesting dramatic changes in remineralization over all hyperthermal events at these sites. Increased remineralization rates could partly account for differences in planktonic and benthic extinction, as observed during the PETM.

Effect of variations in the nitrogen loading rate and seasonality on the operation of a free water surface constructed wetland for treatment of swine wastewater.

PubMed

Plaza de Los Reyes, Catalina; Vidal, Gladys

2015-01-01

The aim of this study was to evaluate the effects of variations in the nitrogen loading rate (NLR) and seasonality on the operational efficiency of a free-water surface constructed wetland (FWS) and on the processes involved in total nitrogen (TN) removal in treating swine wastewater. The system, which operated for 550 days, consisted of a FWS mesocosm inoculated with Typha angustifolia L., using swine wastewater from a storage lagoon as an influent. After operating with nitrogen loading rates (NLRs) of 2.0 to 30.2 kg TN ha(-1)·d(-1), the FWS reduced total nitrogen (TN) concentration by between 21.6 and 51.0%, achieving maximum removal (48.2 ± 3.0%) when the system operated at a NLR below 15.0 kg TN ha(-1)·d(-1). Moreover, operations over 25.0 kg TN ha(-1)·d(-1) resulted in a 50.6% decrease in the maximum FWS efficiency, which may have been related to increased anoxic conditions (< 0.5 mg O2 L(-1); -169.8 ± 70.3 mV) resulting from the high concentration of organic matter in the system (12.3 ± 10.5 g TCOD L(-1)), which hindered nitrification. Ammonia volatilization is considered the main method to remove TN, with an average value of 14.4 ± 6.5% (3.1-26.2%). Maximum volatilization occurred during the summer (21.5 ± 2.4°C) at an NLR higher than 25 kg TN ha(-1)·d(-1) (26.6%), favored by higher temperatures (17.3-19.7°C), and high NH4(+)-N (>600.0 9 mg NH4(+)-N L(-1)) and pH levels (7.1-7.9). Uptake by plants accounted for 14.9% of the TN removed, with the vegetative peak in summer (height: 105.3 cm; diameter: 2.1 cm) at an NLR of 25.3 ± 0.3 kg TN ha(-1)·d(-1). However, growth decreased to 94.4% at an NLR of over 25.3 ± 0.3 kg TN ha(-1)·d(-1) (>379.9 mg NH4(+)-N L(-1)) in autumn (17.4 ± 2.4°C). This was associated with the period of plant senescence and the effects of ammonium phytotoxicity (379.9-624.2 mg NH4(+)-N L(-1)) and continued to the end of the study with the complete loss of macrophyte species. Finally, 1.5% of the TN removed was incorporated into the sediments where NH4(+)-N is the main form of nitrogen, with an accumulative value of 2.6 g m(-2).

Determination of the atmospheric neutrino flux and searches for new physics with AMANDA-II

NASA Astrophysics Data System (ADS)

Abbasi, R.; Abdou, Y.; Ackermann, M.; Adams, J.; Ahlers, M.; Andeen, K.; Auffenberg, J.; Bai, X.; Baker, M.; Barwick, S. W.; Bay, R.; Bazo Alba, J. L.; Beattie, K.; Bechet, S.; Becker, J. K.; Becker, K.-H.; Benabderrahmane, M. L.; Berdermann, J.; Berghaus, P.; Berley, D.; Bernardini, E.; Bertrand, D.; Besson, D. Z.; Bissok, M.; Blaufuss, E.; Boersma, D. J.; Bohm, C.; Bolmont, J.; Böser, S.; Botner, O.; Bradley, L.; Braun, J.; Breder, D.; Burgess, T.; Castermans, T.; Chirkin, D.; Christy, B.; Clem, J.; Cohen, S.; Cowen, D. F.; D'Agostino, M. V.; Danninger, M.; Day, C. T.; de Clercq, C.; Demirörs, L.; Depaepe, O.; Descamps, F.; Desiati, P.; de Vries-Uiterweerd, G.; De Young, T.; Diaz-Velez, J. C.; Dreyer, J.; Dumm, J. P.; Duvoort, M. R.; Edwards, W. R.; Ehrlich, R.; Eisch, J.; Ellsworth, R. W.; Engdegård, O.; Euler, S.; Evenson, P. A.; Fadiran, O.; Fazely, A. R.; Feusels, T.; Filimonov, K.; Finley, C.; Foerster, M. M.; Fox, B. D.; Franckowiak, A.; Franke, R.; Gaisser, T. K.; Gallagher, J.; Ganugapati, R.; Gerhardt, L.; Gladstone, L.; Goldschmidt, A.; Goodman, J. A.; Gozzini, R.; Grant, D.; Griesel, T.; Groß, A.; Grullon, S.; Gunasingha, R. M.; Gurtner, M.; Ha, C.; Hallgren, A.; Halzen, F.; Han, K.; Hanson, K.; Hasegawa, Y.; Heise, J.; Helbing, K.; Herquet, P.; Hickford, S.; Hill, G. C.; Hoffman, K. D.; Hoshina, K.; Hubert, D.; Huelsnitz, W.; Hülß, J.-P.; Hulth, P. O.; Hultqvist, K.; Hussain, S.; Imlay, R. L.; Inaba, M.; Ishihara, A.; Jacobsen, J.; Japaridze, G. S.; Johansson, H.; Joseph, J. M.; Kampert, K.-H.; Kappes, A.; Karg, T.; Karle, A.; Kelley, J. L.; Kenny, P.; Kiryluk, J.; Kislat, F.; Klein, S. R.; Klepser, S.; Knops, S.; Kohnen, G.; Kolanoski, H.; Köpke, L.; Kowalski, M.; Kowarik, T.; Krasberg, M.; Kuehn, K.; Kuwabara, T.; Labare, M.; Laihem, K.; Landsman, H.; Lauer, R.; Leich, H.; Lennarz, D.; Lucke, A.; Lundberg, J.; Lünemann, J.; Madsen, J.; Majumdar, P.; Maruyama, R.; Mase, K.; Matis, H. S.; McParland, C. P.; Meagher, K.; Merck, M.; Mészáros, P.; Middell, E.; Milke, N.; Miyamoto, H.; Mohr, A.; Montaruli, T.; Morse, R.; Movit, S. M.; Münich, K.; Nahnhauer, R.; Nam, J. W.; Nießen, P.; Nygren, D. R.; Odrowski, S.; Olivas, A.; Olivo, M.; Ono, M.; Panknin, S.; Patton, S.; Pérez de Los Heros, C.; Petrovic, J.; Piegsa, A.; Pieloth, D.; Pohl, A. C.; Porrata, R.; Potthoff, N.; Price, P. B.; Prikockis, M.; Przybylski, G. T.; Rawlins, K.; Redl, P.; Resconi, E.; Rhode, W.; Ribordy, M.; Rizzo, A.; Rodrigues, J. P.; Roth, P.; Rothmaier, F.; Rott, C.; Roucelle, C.; Rutledge, D.; Ryckbosch, D.; Sander, H.-G.; Sarkar, S.; Satalecka, K.; Schlenstedt, S.; Schmidt, T.; Schneider, D.; Schukraft, A.; Schulz, O.; Schunck, M.; Seckel, D.; Semburg, B.; Seo, S. H.; Sestayo, Y.; Seunarine, S.; Silvestri, A.; Slipak, A.; Spiczak, G. M.; Spiering, C.; Stanev, T.; Stephens, G.; Stezelberger, T.; Stokstad, R. G.; Stoufer, M. C.; Stoyanov, S.; Strahler, E. A.; Straszheim, T.; Sulanke, K.-H.; Sullivan, G. W.; Swillens, Q.; Taboada, I.; Tarasova, O.; Tepe, A.; Ter-Antonyan, S.; Terranova, C.; Tilav, S.; Tluczykont, M.; Toale, P. A.; Tosi, D.; Turčan, D.; van Eijndhoven, N.; Vandenbroucke, J.; van Overloop, A.; Voigt, B.; Walck, C.; Waldenmaier, T.; Walter, M.; Wendt, C.; Westerhoff, S.; Whitehorn, N.; Wiebusch, C. H.; Wiedemann, A.; Wikström, G.; Williams, D. R.; Wischnewski, R.; Wissing, H.; Woschnagg, K.; Xu, X. W.; Yodh, G.; Yoshida, S.

2009-05-01

The AMANDA-II detector, operating since 2000 in the deep ice at the geographic South Pole, has accumulated a large sample of atmospheric muon neutrinos in the 100 GeV to 10 TeV energy range. The zenith angle and energy distribution of these events can be used to search for various phenomenological signatures of quantum gravity in the neutrino sector, such as violation of Lorentz invariance or quantum decoherence. Analyzing a set of 5511 candidate neutrino events collected during 1387 days of livetime from 2000 to 2006, we find no evidence for such effects and set upper limits on violation of Lorentz invariance and quantum decoherence parameters using a maximum likelihood method. Given the absence of evidence for new flavor-changing physics, we use the same methodology to determine the conventional atmospheric muon neutrino flux above 100 GeV.

Performance and enhanced mechanism of a novel bio-diatomite biofilm pretreatment process treating polluted raw water.

PubMed

Yang, Guang-feng; Feng, Li-juan; Wang, Sha-fei; Yang, Qi; Xu, Xiang-yang; Zhu, Liang

2015-09-01

A lab-scale novel bio-diatomite biofilm process (BDBP) was established for the polluted raw water pretreatment in this study. Results showed that a shorter startup period of BDBP system was achieved under the completely circulated operation mode, and the removal efficiencies of nitrogen and disinfection by-product precursor were effective at low hydraulic retention time of 2-4 h due to high biomass attached to the carrier and diatomite. A maximum NH4(+)-N oxidation potential predicted by modified Stover-Kincannon model was 333.3 mg L(-1) d(-1) in the BDBP system, which was 4.7 times of that in the control reactor. Results demonstrated that the present of bio-diatomite favors the accumulation of functional microbes in the oligotrophic niche, and the pollutants removal performance of this novel process was enhanced for polluted raw water pretreatment. Copyright © 2015 Elsevier Ltd. All rights reserved.

Microbial community structure of different electrode materials in constructed wetland incorporating microbial fuel cell.

PubMed

Wang, Junfeng; Song, Xinshan; Wang, Yuhui; Abayneh, Befkadu; Ding, Yi; Yan, Denghua; Bai, Junhong

2016-12-01

The microbial fuel cell coupled with constructed wetland (CW-MFC) microcosms were operated under fed-batch mode for evaluating the effect of electrode materials on bioelectricity generation and microbial community composition. Experimental results indicated that the bioenergy output in CW-MFC increased with the substrate concentration; maximum average voltage (177mV) was observed in CW-MFC with carbon fiber felt (CFF). In addition, the four different materials resulted in the formation of significantly different microbial community distribution around the anode electrode. The relative abundance of Proteobacteria in CFF and foamed nickel (FN) was significantly higher than that in stainless steel mesh (SSM) and graphite rod (GR) samples. Notably, the findings indicate that CW-MFC utilizing FN anode electrode could apparently improve relative abundance of Dechloromonas, which has been regarded as a denitrifying and phosphate accumulating microorganism. Copyright © 2016 Elsevier Ltd. All rights reserved.

Determination of the Atmospheric Neutrino Flux and Searches for New Physics with AMANDA-II

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

IceCube Collaboration; Klein, Spencer; Collaboration, IceCube

2009-06-02

The AMANDA-II detector, operating since 2000 in the deep ice at the geographic South Pole, has accumulated a large sample of atmospheric muon neutrinos in the 100 GeV to 10 TeV energy range. The zenith angle and energy distribution of these events can be used to search for various phenomenological signatures of quantum gravity in the neutrino sector, such as violation of Lorentz invariance (VLI) or quantum decoherence (QD). Analyzing a set of 5511 candidate neutrino events collected during 1387 days of livetime from 2000 to 2006, we find no evidence for such effects and set upper limits on VLImore » and QD parameters using a maximum likelihood method. Given the absence of evidence for new flavor-changing physics, we use the same methodology to determine the conventional atmospheric muon neutrino flux above 100 GeV.« less

Determination of the atmospheric neutrino flux and searches for new physics with AMANDA-II

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

Abbasi, R.; Andeen, K.; Baker, M.

2009-05-15

The AMANDA-II detector, operating since 2000 in the deep ice at the geographic South Pole, has accumulated a large sample of atmospheric muon neutrinos in the 100 GeV to 10 TeV energy range. The zenith angle and energy distribution of these events can be used to search for various phenomenological signatures of quantum gravity in the neutrino sector, such as violation of Lorentz invariance or quantum decoherence. Analyzing a set of 5511 candidate neutrino events collected during 1387 days of livetime from 2000 to 2006, we find no evidence for such effects and set upper limits on violation of Lorentzmore » invariance and quantum decoherence parameters using a maximum likelihood method. Given the absence of evidence for new flavor-changing physics, we use the same methodology to determine the conventional atmospheric muon neutrino flux above 100 GeV.« less

78 FR 76191 - Operational Tests and Inspections for Compliance With Maximum Authorized Train Speeds and Other...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-16

... Tests and Inspections for Compliance With Maximum Authorized Train Speeds and Other Speed Restrictions... safety advisory; Operational tests and inspections for compliance with maximum authorized train speeds and other speed restrictions. SUMMARY: FRA is issuing Safety Advisory 2013-08 to stress to railroads...

49 CFR 192.328 - Additional construction requirements for steel pipe using alternative maximum allowable operating...

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 3 2012-10-01 2012-10-01 false Additional construction requirements for steel pipe using alternative maximum allowable operating pressure. 192.328 Section 192.328 Transportation... Lines and Mains § 192.328 Additional construction requirements for steel pipe using alternative maximum...

49 CFR 192.328 - Additional construction requirements for steel pipe using alternative maximum allowable operating...

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false Additional construction requirements for steel pipe using alternative maximum allowable operating pressure. 192.328 Section 192.328 Transportation... Lines and Mains § 192.328 Additional construction requirements for steel pipe using alternative maximum...

Shape memory alloy actuated accumulator for ultra-deepwater oil and gas exploration

NASA Astrophysics Data System (ADS)

Patil, Devendra; Song, Gangbing

2016-04-01

As offshore oil and gas exploration moves further offshore and into deeper waters to reach hydrocarbon reserves, it is becoming essential for the industry to develop more reliable and efficient hydraulic accumulators to supply pressured hydraulic fluid for various control and actuation operations, such as closing rams of blowout preventers and controlling subsea valves on the seafloor. By utilizing the shape memory effect property of nitinol, which is a type of shape memory alloy (SMA), an innovative SMA actuated hydraulic accumulator prototype has been developed and successfully tested at Smart Materials and Structure Laboratory at the University of Houston. Absence of gas in the developed SMA accumulator prototype makes it immune to hydrostatic head loss caused by water depth and thus reduces the number of accumulators required in deep water operations. Experiments with a feedback control have demonstrated that the proposed SMA actuated accumulator can provide precisely regulated pressurized fluids. Furthermore the potential use of ultracapacitors along with an embedded system to control the electric power supplied to SMA allows this accumulator to be an autonomous device for deployment. The developed SMA accumulator will make deepwater oil extraction systems more compact and cost effective.

The ESS neutrino facility for CP violation discovery

NASA Astrophysics Data System (ADS)

Baussan, Eric; Bouquerel, Elian; Dracos, Marcos

2017-09-01

The comparatively large value of the neutrino mixing angle θ 13 measured in 2012 by neutrino reactor experiments has opened the possibility to observe for the first time CP violation in the leptonic sector. The measured value of θ 13 also privileges the 2nd oscillation maximum for the discovery of CP violation instead of the usually used 1st oscillation maximum. The sensitivity at the 2nd oscillation maximum is about three times higher than at the 1st oscillation maximum implying a significantly lower sensitivity to systematic errors. Measuring at the 2nd oscillation maximum necessitates a very intense neutrino beam with the appropriate energy. The world’s most intense pulsed spallation neutron source, the European Spallation Source, has a proton linac with 5 MW power and 2 GeV energy. This linac also has the potential to become the proton driver of the world’s most intense neutrino beam with very high potential for the discovery of neutrino CP violation. The physics performance of that neutrino Super Beam in conjunction with a megaton Water Cherenkov neutrino detector installed ca 1000 m down in a mine at a distance of about 500 km from ESS has been evaluated. In addition, the use of such a detector will make it possible to extent the physics program to proton decay, atmospheric neutrinos and astrophysics searches. The ESS proton linac upgrade, the accumulator ring needed for proton pulse compression, the target station optimization and the physics potential are described. In addition to the production of neutrinos, this facility will also be a copious source of muons which could be used to feed a low energy nuSTORM facility, a future neutrino factory or a muon collider. The ESS linac, under construction, will reach full operation at 5 MW by 2023 after which the upgrades for the neutrino facility could start.

Successful resection of a giant mediastinal non-seminomatous germ cell tumor showing fluorodeoxyglucose accumulation after neoadjuvant chemotherapy: report of a case.

PubMed

Takada, Kazuki; Morodomi, Yosuke; Okamoto, Tatsuro; Suzuki, Yuzo; Fujishita, Takatoshi; Kitahara, Hirokazu; Shimamatsu, Shinichiro; Kohno, Mikihiro; Kawano, Daigo; Hidaka, Noriko; Nakanishi, Yoichi; Maehara, Yoshihiko

2014-05-01

A 32-year-old man presented with a mediastinal non-seminomatous germ cell tumor showing fluorodeoxyglucose (FDG) accumulation (maximum standardized uptake value = 22.21) and extremely elevated blood alpha-fetoprotein (AFP) level (9203.0 ng/ml). The patient underwent 4 cycles of neoadjuvant chemotherapy (cisplatin, bleomycin, and etoposide), which normalized the AFP level and reduced the tumor size, allowing complete resection without a support of extracorporeal circulation. Despite preoperative positron emission tomography revealing increased FDG uptake in the residual tumor (maximum standardized uptake value = 3.59), the pathologic evaluation revealed that no viable germ cell tumor cells remained. We believe FDG uptake should not be used as a criterion for surgical resection after neoadjuvant chemotherapy. It is appropriate to resect the residual tumor regardless of FDG uptake after induction chemotherapy if a tumor is resectable and the AFP level normalizes.

Multiple Export Production and Sulfur Isotope Records over the Paleocene Eocene Thermal Maximum

NASA Astrophysics Data System (ADS)

Gray, E.; Paytan, A.

2007-12-01

The Paleocene Eocene Thermal Maximum (PETM) was a global climatic event that occurred 55 million years ago. δ18O values from benthic foraminifera indicate that temperatures rose 4-5°C coeval with a precipitous drop in δ13C values that indicate a new source of carbon rapidly entered the global carbon cycle. Marine barite (BaSO4) was used to evaluate the 1) barite accumulation rate that serves a proxy for export production and 2) the sulfur isotopic composition of seawater that reflects the mass balance of oceanic sulfate (SO42-). Increased barite accumulation rates at the PETM suggest that increased export production and CO2 sequestration was in direct response to the carbon isotope excursion, although not all of the increases are accounted for. High resolution δ34S values are lower but within reasonable range of previously observed values and indicate a decrease in sulfate removal by pyrite deposition.

Controller and interface module for the High-Speed Data Acquisition System correlator/accumulator

NASA Technical Reports Server (NTRS)

Brokl, S. S.

1985-01-01

One complex channel of the High-Speed Data Acquisition System (a subsystem used in the Goldstone solar system radar), consisting of two correlator modules and one accumulator module, is operated by the controller and interface module interfaces are provided to the VAX UNIBUS for computer control, monitor, and test of the controller and correlator/accumulator. The correlator and accumulator modules controlled by this module are the key digital signal processing elements of the Goldstone High-Speed Data Acquisition System. This fully programmable unit provides for a wide variety of correlation and filtering functions operating on a three megaword/second data flow. Data flow is to the VAX by way of the I/O port of a FPS 5210 array processor.

49 CFR 192.623 - Maximum and minimum allowable operating pressure; Low-pressure distribution systems.

Code of Federal Regulations, 2012 CFR

2012-10-01

... distribution systems. (a) No person may operate a low-pressure distribution system at a pressure high enough to...) No person may operate a low pressure distribution system at a pressure lower than the minimum... 49 Transportation 3 2012-10-01 2012-10-01 false Maximum and minimum allowable operating pressure...

49 CFR 192.623 - Maximum and minimum allowable operating pressure; Low-pressure distribution systems.

Code of Federal Regulations, 2011 CFR

2011-10-01

... distribution systems. (a) No person may operate a low-pressure distribution system at a pressure high enough to...) No person may operate a low pressure distribution system at a pressure lower than the minimum... 49 Transportation 3 2011-10-01 2011-10-01 false Maximum and minimum allowable operating pressure...

49 CFR 192.623 - Maximum and minimum allowable operating pressure; Low-pressure distribution systems.

Code of Federal Regulations, 2013 CFR

2013-10-01

... distribution systems. (a) No person may operate a low-pressure distribution system at a pressure high enough to...) No person may operate a low pressure distribution system at a pressure lower than the minimum... 49 Transportation 3 2013-10-01 2013-10-01 false Maximum and minimum allowable operating pressure...

49 CFR 192.623 - Maximum and minimum allowable operating pressure; Low-pressure distribution systems.

Code of Federal Regulations, 2014 CFR

2014-10-01

... distribution systems. (a) No person may operate a low-pressure distribution system at a pressure high enough to...) No person may operate a low pressure distribution system at a pressure lower than the minimum... 49 Transportation 3 2014-10-01 2014-10-01 false Maximum and minimum allowable operating pressure...

49 CFR 192.623 - Maximum and minimum allowable operating pressure; Low-pressure distribution systems.

Code of Federal Regulations, 2010 CFR

2010-10-01

... distribution systems. (a) No person may operate a low-pressure distribution system at a pressure high enough to...) No person may operate a low pressure distribution system at a pressure lower than the minimum... 49 Transportation 3 2010-10-01 2010-10-01 false Maximum and minimum allowable operating pressure...

Carbon accumulation in peatlands of West Siberia over the last 2000 years

NASA Astrophysics Data System (ADS)

Beilman, David W.; MacDonald, Glen M.; Smith, Laurence C.; Reimer, Paula J.

2009-03-01

We use a network of cores from 77 peatland sites to determine controls on peat C content and peat C accumulation over the last 2000 years (since 2 ka) across Russia's West Siberian Lowland (WSL), the world's largest wetland region. Our results show a significant influence of fossil plant composition on peat C content, with peats dominated by Sphagnum having a lower C content. Radiocarbon-derived C accumulation since 2 ka at 23 sites is highly variable from site to site, but displays a significant N-S trend of decreasing accumulation at higher latitudes. Northern WSL peatlands show relatively small C accumulation of 7 to 35 kg C m-2 since 2 ka. In contrast, peatlands south of 60°N show larger accumulation of 42 to 88 kg C m-2. Carbon accumulation since 2 ka varies significantly with modern mean annual air temperature, with maximum C accumulation found between -1 and 0°C. Rates of apparent C accumulation since 2 ka show no significant relationship to long-term Holocene averages based on total C accumulation. A GIS-based extrapolation of our site data suggests that a substantial amount (˜40%) of total WSL peat C has accumulated since 2 ka, with much of this accumulation south of 60°N. The large peatlands in the southern WSL may be an important component of the Eurasian terrestrial C sink, and future warming could result in a shift northward in long-term WSL C sequestration.

46 CFR 109.575 - Accumulation of liquids on helicopter decks.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Accumulation of liquids on helicopter decks. 109.575 Section 109.575 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS OPERATIONS Miscellaneous § 109.575 Accumulation of liquids on helicopter decks. The master...

46 CFR 109.575 - Accumulation of liquids on helicopter decks.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Accumulation of liquids on helicopter decks. 109.575 Section 109.575 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS OPERATIONS Miscellaneous § 109.575 Accumulation of liquids on helicopter decks. The master...

46 CFR 109.575 - Accumulation of liquids on helicopter decks.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Accumulation of liquids on helicopter decks. 109.575 Section 109.575 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS OPERATIONS Miscellaneous § 109.575 Accumulation of liquids on helicopter decks. The master...

46 CFR 109.575 - Accumulation of liquids on helicopter decks.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Accumulation of liquids on helicopter decks. 109.575 Section 109.575 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS OPERATIONS Miscellaneous § 109.575 Accumulation of liquids on helicopter decks. The master...

46 CFR 109.575 - Accumulation of liquids on helicopter decks.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Accumulation of liquids on helicopter decks. 109.575 Section 109.575 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS OPERATIONS Miscellaneous § 109.575 Accumulation of liquids on helicopter decks. The master...

Deciphering adverse effects of heavy metals on diverse wheat germplasm on irrigation with urban wastewater of mixed municipal-industrial origin.

PubMed

Ali, Zeshan; Mujeeb-Kazi, Abdul; Quraishi, Umar Masood; Malik, Riffat Naseem

2018-04-25

The current study provides one of the first attempts to identify tolerant, moderately sensitive, and highly sensitive wheat genotypes on the basis of heavy metal accumulation, biochemical attributes, and human health risk assessments on urban wastewater (UW) irrigation. Mean heavy metals (Fe, Co, Ni, Cu, Zn, Pb, Cd, Cr, Mn) and macro-nutrients (Na, K, Ca, Mg) levels increased in the roots, stem, and grains of studied genotypes. Except K (stem > root > grain), all metals were accumulated in highest concentrations in roots followed by stem and grains. Principal component analyses (PCA) identified three groups of UW-irrigated genotypes which were confirmed by hierarchical agglomerative cluster analyses (HACA). Wheat genotypes with the lowest metal accumulation were regarded as tolerant, whereas those with maximum accumulation were considered highly sensitive. Tolerant genotypes showed the lowest hazard quotient for heavy metals, i.e., Co, Mn, Cd, Cu, Fe, Pb, and Cr, and hazard index (HI) values (adults, 2.04; children, 2.27) than moderately and highly sensitive genotypes. Higher health risks (HI) associated with moderate (adults 2.26; children 2.53) and highly sensitive (adults 2.52; children 2.82) genotypes revealed maximum uptake of heavy metals. The heatmap showed higher mean biochemical levels of chlorophyll, carotenoids, membrane stability index (MSI%), sugars, proteins, proline, superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) in tolerant genotypes than remaining genotypes. With the lowest metal accumulation and advanced biochemical mechanisms to cope with the adverse effects of heavy metals in their plant bodies, tolerant genotypes present a better option for cultivation in areas receiving UW or similar type of wastewater.

Influence of light quality on growth, secondary metabolites production and antioxidant activity in callus culture of Rhodiola imbricata Edgew.

PubMed

Kapoor, Sahil; Raghuvanshi, Rinky; Bhardwaj, Pushpender; Sood, Hemant; Saxena, Shweta; Chaurasia, Om Prakash

2018-06-01

Rhodiola imbricata is a rare medicinal herb well-known for its adaptogenic and antioxidant properties due to the presence of a diverse array of secondary metabolites, including phenylethanoids and phenylpropanoids. These secondary metabolites are generating considerable interest due to their potential applications in pharmaceutical and nutraceutical industries. The present study investigated the influence of light quality on growth, production of industrially important secondary metabolites and antioxidant activity in callus cultures of Rhodiola imbricata. Callus cultures of Rhodiola imbricata were established under different light conditions: 100% red, 100% blue, 100% green, RGB (40% red: 40% green: 20% blue) and 100% white (control). The results showed that the callus cultures grown under red light accumulated maximum amount of biomass (7.43 g/l) on day 21 of culture, as compared to other light conditions. Maximum specific growth rate (0.126 days -1 ) and doubling time (132.66 h) was observed in callus cultures grown under red light. Reverse phase-high performance liquid chromatographic (RP-HPLC) analysis revealed that the callus cultures exposed to blue light accumulated maximum amount of Salidroside (3.12 mg/g DW) on day 21 of culture, as compared to other light conditions. UV-Vis spectrophotometric analysis showed that the callus cultures exposed to blue light accumulated maximum amount of total phenolics (11.84 mg CHA/g DW) and total flavonoids (5.53 mg RE/g DW), as compared to other light conditions. Additionally, callus cultures grown under blue light displayed enhanced DPPH free radical scavenging activity (53.50%). Callus cultures grown under different light conditions showed no significant difference in ascorbic acid content (11.05-13.90 mg/g DW) and total antioxidant capacity (27.37-30.17 mg QE/g DW). The correlation analysis showed a positive correlation between total phenolic content and DPPH free radical scavenging activity in callus cultures (r = 0.85). Taken together, these results demonstrate the remarkable potential of light quality on biomass accumulation and production of industrially important secondary metabolites in callus cultures of Rhodiola imbricata. This study will open new avenues and perspectives towards abiotic elicitation strategies for sustainable growth and enhanced production of bioactive compounds in in-vitro cultures of Rhodiola imbricata. Copyright © 2018 Elsevier B.V. All rights reserved.

Effect of famine-phase reduced aeration on polyhydroxyalkanoate accumulation in aerobic granules.

PubMed

Vjayan, T; Vadivelu, V M

2017-12-01

The effects of variable aeration in the famine period on polyhydroxyalkanoate (PHA) accumulation in aerobic granules were investigated. Results showed that regardless of the aeration rates used during famine period, all aerobic granules achieved a similar chemical oxygen demand removal and PHA content. The decrease in famine-period aeration rates accelerated the maximum PHA accumulation together with increase in granular size and settling ability. The PHA-accumulating microorganisms were found to have shifted closer to the surface of the granules when the aeration rate was reduced. Moreover, PHA compositional changes occurred, where the hydroxyvalerate content had increased with the reduction in aeration rate. Ultimately, the results indicate that the requirement of aeration for PHA accumulation in aerobic granules is highly insignificant in the famine phase. PHA production in aerobic granules under zero aeration in the famine period may result in an energy input reduction of up to 74%. Copyright © 2017 Elsevier Ltd. All rights reserved.

Bioaccumulation of Vanadium by Vanadium-Resistant Bacteria Isolated from the Intestine of Ascidia sydneiensis samea.

PubMed

Romaidi; Ueki, Tatsuya

2016-06-01

Isolation of naturally occurring bacterial strains from metal-rich environments has gained popularity due to the growing need for bioremediation technologies. In this study, we found that the vanadium concentration in the intestine of the vanadium-rich ascidian Ascidia sydneiensis samea could reach 0.67 mM, and thus, we isolated vanadium-resistant bacteria from the intestinal contents and determined the ability of each bacterial strain to accumulate vanadium and other heavy metals. Nine strains of vanadium-resistant bacteria were successfully isolated, of which two strains, V-RA-4 and S-RA-6, accumulated vanadium at a higher rate than did the other strains. The maximum vanadium absorption by these bacteria was achieved at pH 3, and intracellular accumulation was the predominant mechanism. Each strain strongly accumulated copper and cobalt ions, but accumulation of nickel and molybdate ions was relatively low. These bacterial strains can be applied to protocols for bioremediation of vanadium and heavy metal toxicity.

Soil development on a Pleistocene terrace sequence, Boise Valley, Idaho

USGS Publications Warehouse

Othberg, K.L.; McDaniel, P.A.; Fosberg, M.A.

1997-01-01

Study of a sequence of terraces in the western Snake River Plain of Idaho reveals a record of at least seven terraces, the ages of which span the Pleistocene. In the Boise Valley, the youngest terraces are less than -14,500 yr and the oldest terraces are -1.7 Ma. Within this sequence, several relationships exist between soil morphology and terrace chronology. On terraces older than -14,500 yr, argillic horizon development generally increases with terrace age with maximum development occurring in soils of the oldest terraces. CaCO3- and SiO2-cemented duripans are found in soils on terraces that are late middle Pleistocene and older. By virtue of their physical and chemical properties, duripans are very resistant to erosion, and therefore provide stable records of CaCO3 and SiO2 accumulation throughout multiple cycles of loess deposition onto the terrace treads, pedogenesis, and partial erosion. Mean duripan thickness increases with age to a maximum of 0.66 m on the oldest terraces. Our results suggest that a geomorphic surface age of approximately 130,000 yr is required to form the initial plugged horizon that is characteristic of a duripan. CaCO3 and SiO2 accumulation is most rapid in duripans occupying geomorphic surfaces with ages ranging from 130,000 to 300,000 yr. After this, apparent accumulation rates decrease and little additional accumulation of these cementing agents occurs with time.

A carbon accumulation maximum during the Medieval Climate Anomaly in the world’s biggest bog, Siberia

NASA Astrophysics Data System (ADS)

Beilman, D.; MacDonald, G. M.

2009-12-01

The West Siberia Lowland is the most carbon-rich northern wetland region, holding an important portion of total northern peatland carbon (70 Gt of 270-450 Gt C) mainly in the southern lowland (44 Gt) in very large peatlands. The largest of these, the Great Vasyugan Bog complex, spans 63,252 km2 and alone holds ~11 Gt C. Our previous work has shown that recent-past growth of WSL peat C pool has been greatest in southern WSL in large peatlands close to the southern limit of peatland distribution. In this study, we investigate a Great Vasyugan site to investigate peat carbon sensitivity in two ways: 1) assess past changes in vegetation, species-specific 13C geochemistry, and rate of carbon accumulation relative to recent-past climate variation, and 2) assess the relative lability of this deep peat C through laboratory incubations. Carbon accumulation over the last 2000 years, a period of relatively consistent vegetation and litter inputs but variable local hydrology, reached a maximum between 1150 and 1350 AD during Medieval Climate Anomaly conditions. A carbon accumulation minimum occurred between about 1350 and 1550 AD. Regardless of depth, age, or rate of carbon burial, deep peat from between 30 and 230 cm below the surface showed a similar rate of potential aerobic respiration that changed little over 42 days of incubation. Taken together, these data suggest that in some peatlanlds warmer and hydrologically-variable conditions can promote long-term belowground carbon storage.

49 CFR 192.620 - Alternative maximum allowable operating pressure for certain steel pipelines.

Code of Federal Regulations, 2014 CFR

2014-10-01

... for certain steel pipelines. 192.620 Section 192.620 Transportation Other Regulations Relating to... STANDARDS Operations § 192.620 Alternative maximum allowable operating pressure for certain steel pipelines..., 2, or 3 location; (2) The pipeline segment is constructed of steel pipe meeting the additional...

49 CFR 192.620 - Alternative maximum allowable operating pressure for certain steel pipelines.

Code of Federal Regulations, 2011 CFR

2011-10-01

... of a maximum allowable operating pressure based on higher stress levels in the following areas: Take... pipeline at the increased stress level under this section with conventional operation; and (ii) Describe... targeted audience; and (B) Include information about the integrity management activities performed under...

49 CFR 192.620 - Alternative maximum allowable operating pressure for certain steel pipelines.

Code of Federal Regulations, 2013 CFR

2013-10-01

... of a maximum allowable operating pressure based on higher stress levels in the following areas: Take... pipeline at the increased stress level under this section with conventional operation; and (ii) Describe... targeted audience; and (B) Include information about the integrity management activities performed under...

49 CFR 192.620 - Alternative maximum allowable operating pressure for certain steel pipelines.

Code of Federal Regulations, 2012 CFR

2012-10-01

... of a maximum allowable operating pressure based on higher stress levels in the following areas: Take... pipeline at the increased stress level under this section with conventional operation; and (ii) Describe... targeted audience; and (B) Include information about the integrity management activities performed under...

76 FR 1504 - Pipeline Safety: Establishing Maximum Allowable Operating Pressure or Maximum Operating Pressure...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-10

... profile that is dependent upon the pipelines attributes, its geographical location, design, operating... type of threats posed by the pipeline segment, including consideration of the age, design, pipe... calculation. There are several methods available for establishing MAOP or MOP. A hydrostatic pressure test...

Phase and structural transformations in VVER-440 RPV base metal after long-term operation and recovery annealing

NASA Astrophysics Data System (ADS)

Kuleshova, E. A.; Gurovich, B. A.; Maltsev, D. A.; Frolov, A. S.; Bukina, Z. V.; Fedotova, S. V.; Saltykov, M. A.; Krikun, E. V.; Erak, D. Yu; Zhurko, D. A.; Safonov, D. V.; Zhuchkov, G. M.

2018-04-01

This study was carried out to evaluate the possibility of 1st generation VVER-440 reactors lifetime extension by recovery re-annealing with the respect to base metal (BM). Comprehensive studies of the structure and properties of BM templates (samples cut from the inner surface of the shells in beltline region) of operating VVER-440 reactor (after primary standard recovery annealing 475 °C/150 h and subsequent long-term re-irradiation within reactor pressure vessel (RPV)) were conducted. These templates were also subjected to laboratory re-annealing 475 °C/150 h. TEM, SEM and APT studies of BM after laboratory re-annealing revealed significant recovery of radiation-induced hardening elements (Cu-rich precipitates and dislocation loops). Simultaneously a process of strong phosphorus accumulation at grain boundaries occurs since annealing temperature corresponds to the maximum reversible temper brittleness development. The latter is not observed for VVER-440 weld metal (WM). Comparative assessment of the properties return level for the beltline BM templates after recovery re-annealing 475 °C/150 h showed that it does not reach the one typical for beltline WM after the same annealing.

Continuous energy recovery and nutrients removal from molasses wastewater by synergistic system of dark fermentation and algal culture under various fermentation types.

PubMed

Ren, Hong-Yu; Kong, Fanying; Ma, Jun; Zhao, Lei; Xie, Guo-Jun; Xing, Defeng; Guo, Wan-Qian; Liu, Bing-Feng; Ren, Nan-Qi

2018-03-01

Synergistic system of dark fermentation and algal culture was initially operated at batch mode to investigate the energy production and nutrients removal from molasses wastewater in butyrate-type, ethanol-type and propionate-type fermentations. Butyrate-type fermentation was the most appropriate fermentation type for the synergistic system and exhibited the accumulative hydrogen volume of 658.3 mL L -1 and hydrogen yield of 131.7 mL g -1 COD. By-products from dark fermentation (mainly acetate and butyrate) were further used to cultivate oleaginous microalgae. The maximum algal biomass and lipid content reached 1.01 g L -1 and 38.5%, respectively. In continuous operation, the synergistic system was stable and efficient, and energy production increased from 8.77 kJ L -1  d -1 (dark fermentation) to 17.3 kJ L -1  d -1 (synergistic system). Total COD, TN and TP removal efficiencies in the synergistic system reached 91.1%, 89.1% and 85.7%, respectively. This study shows the potential of the synergistic system in energy recovery and wastewater treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Nitrite accumulation performance of aerobic MBBR treating Lurgi coal gasification waste water by adjusting pollutant load and DO concentration.

PubMed

Li, Hui-Qiang; Han, Hong-Jun

2015-01-01

An aerobic moving bed biofilm reactor (MBBR) was adopted to treat Lurgi coal gasification waste water (LCGW) in about 10 months. The pollutant load and dissolve oxygen (DO) concentration were adjusted by trying to maximize the accumulation of [Formula: see text] in the MBBR for LCGW treatment. The highest [Formula: see text] accumulation proportion [Formula: see text] was 73.9%, but was not stable with influent chemical oxygen demand (COD) and DO concentrations of around 1000 and 1.5 mg/L, respectively. Around 1500 mg/L of influent COD concentration and 1.5 mg/L of DO concentration were proper operation conditions for the aerobic MBBR to achieve relatively stable [Formula: see text] accumulation, with [Formula: see text] ratio at 53% and [Formula: see text] ratio at just 4.3% in the effluent. More specifically, free ammonia concentration and DO concentration affected [Formula: see text] accumulation much more obvious than phenols concentration. The activity and quantity of nitrifying bacteria growth in suspended sludge and biofilm of the MBBR were monitored simultaneously to explain the variations of [Formula: see text] accumulation performance under different operation conditions. An aerobic moving bed biofilm reactor (MBBR) was adopted to treat Lurgi coal gasification waste water (LCGW)in about 10 months. The pollutant load and dissolve oxygen (DO) concentration were adjusted by trying to maximize the accumulation of NO(−)(2)−N in the MBBR for LCGW treatment. The highest NO(−)(2)−N accumulation proportion(NO(−)(2)−Neffluent/TN effluent) was 73.9%, but was not stable with influent chemical oxygen demand (COD) and DO concentrations of around 1000 and 1.5 mg/L, respectively. Around 1500 mg/L of influent COD concentration and 1.5 mg/L of DO concentration were proper operation conditions for the aerobic MBBR to achieve relatively stable NO(−)(2)−N accumulation,with NO(−)(2)−N/TN ratio at 53% and NO(-)(3)−N/TN ratio at just 4.3% in the effluent. More specifically, free ammonia concentration and DO concentration affected NO(2)(−)N accumulation much more obvious than phenols concentration. The activity and quantity of nitrifying bacteria growth in suspended sludge and biofilm of the MBBR were monitored simultaneously toexplain the variations of NO(−)(2)−N accumulation performance under different operation conditions.

Interplanetary Trajectories, Encke Method (ITEM)

NASA Technical Reports Server (NTRS)

Whitlock, F. H.; Wolfe, H.; Lefton, L.; Levine, N.

1972-01-01

Modified program has been developed using improved variation of Encke method which avoids accumulation of round-off errors and avoids numerical ambiguities arising from near-circular orbits of low inclination. Variety of interplanetary trajectory problems can be computed with maximum accuracy and efficiency.

49 CFR 174.86 - Maximum allowable operating speed.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Handling of Placarded Rail Cars, Transport Vehicles and Freight Containers § 174.86 Maximum allowable operating speed. (a) For molten metals and molten glass shipped in packagings other than those prescribed in...

49 CFR 174.86 - Maximum allowable operating speed.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Handling of Placarded Rail Cars, Transport Vehicles and Freight Containers § 174.86 Maximum allowable operating speed. (a) For molten metals and molten glass shipped in packagings other than those prescribed in...

49 CFR 174.86 - Maximum allowable operating speed.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Handling of Placarded Rail Cars, Transport Vehicles and Freight Containers § 174.86 Maximum allowable operating speed. (a) For molten metals and molten glass shipped in packagings other than those prescribed in...

Altitude-Test-Chamber Investigation of a Solar Afterburner on the 24C Engine I - Operational Characteristics and Altitude Limits

NASA Technical Reports Server (NTRS)

1948-01-01

An altitude-test-chamber investigation was conducted to determine the operational characteristics and altitude blow-out limits of a Solar afterburner in a 24C engine. At rated engine speed and maximum permissible turbine-discharge temperature, the altitude limit as determined by combustion blow-out occurred as a band of unstable operation of about 8000 feet altitude in width with maximum altitude limits from 32,000 feet at a Mach number of 0.3 to about 42,000 feet at a Mach number of 1.0. The maximum fuel-air ratio of the afterburner, as limited by maximum permissible turbine-discharge gas temperatures at rated engine speed, varied between 0.0295 and 0.0380 over a range of flight Mach numbers from 0.25 to 1.0 and at altitudes of 20,000 and 30,000 feet. Over this range of operating conditions, the fuel-air ratio at which lean blow-out occurred was from 10 to 19 percent below these maximum fuel-air ratios. Combustion was very smooth and uniform during operation; however, ignition of the burner was very difficult throughout the investigation. A failure of the flame holder after 12 hours and 15 minutes of afterburner operation resulted in termination of the investigation.

Long-term operation of microbial electrosynthesis cell reducing CO2 to multi-carbon chemicals with a mixed culture avoiding methanogenesis.

PubMed

Bajracharya, Suman; Yuliasni, Rustiana; Vanbroekhoven, Karolien; Buisman, Cees J N; Strik, David P B T B; Pant, Deepak

2017-02-01

In microbial electrosynthesis (MES), CO 2 can be reduced preferably to multi-carbon chemicals by a biocathode-based process which uses electrochemically active bacteria as catalysts. A mixed anaerobic consortium from biological origin typically produces methane from CO 2 reduction which circumvents production of multi-carbon compounds. This study aimed to develop a stable and robust CO 2 reducing biocathode from a mixed culture inoculum avoiding the methane generation. An effective approach was demonstrated based on (i) an enrichment procedure involving inoculum pre-treatment and several culture transfers in H 2 :CO 2 media, (ii) a transfer from heterotrophic to autotrophic growth and (iii) a sequential batch operation. Biomass growth and gradual acclimation to CO 2 electro-reduction accomplished a maximum acetate production rate of 400mgL catholyte -1 d -1 at -1V (vs. Ag/AgCl). Methane was never detected in more than 300days of operation. Accumulation of acetate up to 7-10gL -1 was repeatedly attained by supplying (80:20) CO 2 :N 2 mixture at -0.9 to -1V (vs. Ag/AgCl). In addition, ethanol and butyrate were also produced from CO 2 reduction. Thus, a robust CO 2 reducing biocathode can be developed from a mixed culture avoiding methane generation by adopting the specific culture enrichment and operation procedures without the direct addition of chemical inhibitor. Copyright © 2016 Elsevier B.V. All rights reserved.

Mercury accumulation in Devils Lake, North Dakota effects of environmental variation in closed-basin lakes on mercury chronologies

USGS Publications Warehouse

Lent, R.M.; Alexander, C.R.

1997-01-01

Sediment cores were collected from lakes in the Devils Lake Basin in North Dakota to determine if mercury (Hg) accumulation chronologies from sediment-core data are good indicators of variations in Hg accumulation rates in saline lakes. Sediment cores from Creel Bay and Main Bay, Devils Lake were selected for detailed analysis and interpretation. The maximum Hg concentration in the Creel Bay core was 0.15 micrograms per gram at 8 to 9 centimeters. The maximum Hg concentration in the Main Bay core was 0.07 micrograms per gram at 5 to 7 centimeters. The general decreases in Hg concentrations with depth are attributed to historic variations in atmospheric Hg deposition rate. Hg stratigraphies combined with 210Pb and 137Cs dating analyses yield Hg chronologies that indicate a general increase in Hg accumulation rates in Devils Lake since the middle of the 19th century. Mean modern Hg accumulation rates in Creel Bay were 4.9 nanograms per square centimeter per year, and rates in Main Bay were 1.8 nanograms per square centimeter per year. Mean preindustrial Hg accumulation rates in Creel Bay were 1.2 nanograms per square centimeter per year, and rates in Main Bay were 1.6 nanograms per square centimeter per year. Relatively low Hg concentrations in recent sediments in the Devils Lake Basin, along with similarities in Hg accumulation rates between lakes in the Devils Lake Basin and other lakes in the northern interior of North America, indicate that local sources of Hg are not important sources of Hg. Results of the study indicate that accurate Hg chronologies are discernible in sediment cores collected from saline lakes. However, spatial and temporal variations in lake level and water chemistry common to saline lakes make interpretation of radioisotopic and geochemical chronologies difficult. Hg geochemistry in Devils Lake, and presumably in other saline lakes, is dynamic. The results of this study indicate that the absolute amount of sediment transported to Devils Lake, along with the associated Hg and total organic carbon, and the distribution of sedimentation patterns in Devils Lake may be affected by changing lake levels.

Dynamics of polyhydroxyalkanoate accumulation in aerobic granules during the growth-disintegration cycle.

PubMed

Gobi, K; Vadivelu, V M

2015-11-01

The polyhydroxyalkanoate (PHA) accumulation dynamics in aerobic granules that undergo the growth-disintegration cycle were investigated. Four sequencing batch reactors (SBR) were inoculated with aerobic granules at different stages of development (different sizes). Different sizes of aerobic granules showed varying PHA contents. Thus, further study was conducted to investigate the diffusion of substrate and oxygen on PHA accumulation using various organic loading rates (OLR) and aeration rates (AR). An increase in OLR from 0.91 to 3.64kg COD/m(3)day increased the PHA content from 0.66 to 0.87g PHA/g CDW. Meanwhile, an AR increase from 1 to 4L/min only accelerated the maximum PHA accumulation without affecting the PHA content. However, the PHA composition only changes with AR, while the hydroxyvalerate (HV) content increased at a higher AR. Copyright © 2015 Elsevier Ltd. All rights reserved.

Shallow magma accumulation at Kīlauea Volcano, Hawai‘i, revealed by microgravity surveys

USGS Publications Warehouse

Johnson, Daniel J.; Eggers, Albert A.; Bagnardi, Marco; Battaglia, Maurizio; Poland, Michael P.; Miklius, Asta

2010-01-01

Using microgravity data collected at Kīlauea Volcano, Hawai‘i (United States), between November 1975 and January 2008, we document significant mass increase beneath the east margin of Halema‘uma‘u Crater, within Kīlauea's summit caldera. Surprisingly, there was no sustained uplift accompanying the mass accumulation. We propose that the positive gravity residual in the absence of significant uplift is indicative of magma accumulation in void space (probably a network of interconnected cracks), which may have been created when magma withdrew from the summit in response to the 29 November 1975 M = 7.2 south flank earthquake. Subsequent refilling documented by gravity represents a gradual recovery from that earthquake. A new eruptive vent opened at the summit of Kīlauea in 2008 within a few hundred meters of the positive gravity residual maximum, probably tapping the reservoir that had been accumulating magma since the 1975 earthquake.

Shallow magma accumulation at Kilauea Volcano, Hawai'i, revealed by microgravity surveys

USGS Publications Warehouse

Johnson, David J.; Eggers, Albert A.; Bagnardi, Marco; Battaglia, Maurizio; Poland, Michael P.; Miklius, Asta

2010-01-01

Using microgravity data collected at Kilauea Volcano, Hawai'i (United States), between November 1975 and January 2008, we document significant mass increase beneath the east margin of Halema'uma'u Crater, within Kilauea's summit caldera. Surprisingly, there was no sustained uplift accompanying the mass accumulation. We propose that the positive gravity residual in the absence of significant uplift is indicative of magma accumulation in void space (probably a network of interconnected cracks), which may have been created when magma withdrew from the summit in response to the 29 November 1975 M = 7.2 south flank earthquake. Subsequent refilling documented by gravity represents a gradual recovery from that earthquake. A new eruptive vent opened at the summit of Kilauea in 2008 within a few hundred meters of the positive gravity residual maximum, probably tapping the reservoir that had been accumulating magma since the 1975 earthquake.

Study of Cycling Air-Cooling System with a Cold Accumulator for Micro Gas-Turbine Installations

NASA Astrophysics Data System (ADS)

Ochkov, V. F.; Stepanova, T. A.; Katenev, G. M.; Tumanovskii, V. A.; Borisova, P. N.

2018-05-01

Using the cycling air-cooling systems of the CTIC type (Combustion Turbine Inlet Cooling) with a cold accumulator in a micro gas-turbine installation (micro-GTI) to preserve its capacity under the seasonal temperature rise of outside air is described. Water ice is used as the body-storage in the accumulators, and ice water (water at 0.5-1.0°C) is used as the body that cools air. The ice water circulates between the accumulator and the air-water heat exchanger. The cold accumulator model with renewable ice resources is considered. The model contains the heat-exchanging tube lattice-evaporator covered with ice. The lattice is cross-flowed with water. The criterion heat exchange equation that describes the process in the cold accumulator under consideration is presented. The calculations of duration of its active operation were performed. The dependence of cold accumulator service life on water circulation rate was evaluated. The adequacy of the design model was confirmed experimentally in the mock-up of the cold accumulator with a refrigerating machine periodically creating a 200 kg ice reserve in the reservoir-storage. The design model makes it possible to determine the weight of ice reserve of the discharged cold accumulator for cooling the cycle air in the operation of a C-30 type micro- GTI produced by the Capstone Company or micro-GTIs of other capacities. Recommendations for increasing the working capacity of cold accumulators of CTIC-systems of a micro-GTI were made.

Microprocessor-controlled step-down maximum-power-point tracker for photovoltaic systems

NASA Astrophysics Data System (ADS)

Mazmuder, R. K.; Haidar, S.

1992-12-01

An efficient maximum power point tracker (MPPT) has been developed and can be used with a photovoltaic (PV) array and a load which requires lower voltage than the PV array voltage to be operated. The MPPT makes the PV array to operate at maximum power point (MPP) under all insolation and temperature, which ensures the maximum amount of available PV power to be delivered to the load. The performance of the MPPT has been studied under different insolation levels.

Studies on the Mode of Action of Acifluorfen-Methyl in Nonchlorophyllous Soybean Cells 1

PubMed Central

Matringe, M.; Scalla, R.

1988-01-01

Phytotoxic effects of the herbicide acifluorfen-methyl on nonchlorophyllous soybean cells were estimated by 86Rb leakage. An action spectrum study showed maximum injury at 350 to 450 nanometers, with lesser activity between 450 and 700 nanometers. Cells treated in the dark with acifluorfen-methyl accumulated fluorescent pigments with the spectral characteristics of protoporphyrin IX. The action spectrum of acifluorfen-methyl matched the absorption spectrum of this tetrapyrrole, and the extent of cellular damage in the light was related to the degree of fluorescent pigment accumulation. We propose that the phytotoxicity of diphenyl ether herbicides could be explained by their ability to cause abnormal accumulations of tetrapyrroles, which in turn induce lethal photooxidative reactions. PMID:16665956

40 CFR Table 3 to Subpart Hhh of... - Operating Parameters To Be Monitored and Minimum Measurement and Recording Frequencies

Code of Federal Regulations, 2010 CFR

2010-07-01

... rural HMIWI HMIWI a with dry scrubber followed by fabric filter HMIWI a with wet scrubber HMIWI a with dry scrubber followed by fabric filter and wet scrubber Maximum operating parameters: Maximum charge rate Once per charge Once per charge ✔ ✔ ✔ ✔ Maximum fabric filter inlet temperature Continuous Once...

Improving flexibility characteristics of 200 MW unit

NASA Astrophysics Data System (ADS)

Taler, Jan; Trojan, Marcin; Taler, Dawid; Dzierwa, Piotr; Kaczmarski, Karol

2017-03-01

Calculations were performed of the thermal system of a power plant with installed water pressure tanks. The maximum rise in the block electric power resulting from the shut-off of low-pressure regenerative heaters is determined. At that time, the boiler is fed with hot water from water pressure tanks acting as heat accumulators. Accumulation of hot water in water tanks is also proposed in the periods of the power unit small load. In order to lower the plant electric power in the off-peak night hours, water heated in low-pressure regenerative heaters and feed water tank to the nominal temperature is directed to water pressure tanks. The water accumulated during the night is used to feed the boiler during the period of peak demand for electricity. Drops in the power block electric power were determined for different capacities of the tanks and periods when they are charged. A financial and economic profitability analysis (of costs and benefits) is made of the use of tanks for a 200 MW power unit. Operating in the automatic system of frequency and power control, the tanks may also be used to ensure a sudden increase in the electric power of the unit. The results of the performed calculations and analyses indicate that installation of water pressure tanks is well justified. The investment is profitable. Water pressure tanks may not only be used to reduce the power unit power during the off-peak night hours and raise it in the periods of peak demand, but also to increase the power capacity fast at any time. They may also be used to fill the boiler evaporator with hot water during the power unit start-up from the cold state.

Kinetics of phosphate uptake, growth, and accumulation of cyclic diphosphoglycerate in a phosphate-limited continuous culture of Methanobacterium thermoautotrophicum.

PubMed Central

Krueger, R D; Harper, S H; Campbell, J W; Fahrney, D E

1986-01-01

The archaebacterium Methanobacterium thermoautotrophicum was grown in continuous culture at 65 degrees C in a phosphate-limited medium at specific growth rates from 0.06 to 0.28 h-1 (maximum growth rate [mu max] = 0.36 h-1). Cyclic-2,3-diphosphoglycerate (cyclic DPG) levels ranged from 2 to 20 mM in Pi-limited cells, compared with about 30 mM in batch-grown cells. The Monod constant for Pi-limited growth was 5 nM. Pi uptake rates were determined by following the disappearance of 32Pi from the medium. Interrupting the H2 supply stopped the uptake of Pi and the release of organic phosphates. Little or no efflux of Pi occurred in the presence or absence of H2. Pi uptake of cells adapted to nanomolar Pi concentrations could be accounted for by the operation of one uptake system with an apparent Km of about 25 nM and a Vmax of 58 nmol of Pi per min per g (dry weight). Uptake curves at 30 microM Pi or above were biphasic due to a sevenfold decrease in Vmax after an initial phase of rapid movement of Pi into the cell. Under these conditions the growth rate slowed to zero and the cyclic DPG pool expanded before growth resumed. Thus, three properties of M. thermoautotrophicum make it well adapted to live in a low-P environment: the presence of a low-Km, high-Vmax uptake system for Pi; the ability to accumulate cyclic DPG rapidly; and a growth strategy in which accumulation of Pi and cyclic DPG takes precedence over a shift-up in growth rate when excess Pi becomes available. PMID:3722128

Kinetics of phosphate uptake, growth, and accumulation of cyclic diphosphoglycerate in a phosphate-limited continuous culture of Methanobacterium thermoautotrophicum.

PubMed

Krueger, R D; Harper, S H; Campbell, J W; Fahrney, D E

1986-07-01

The archaebacterium Methanobacterium thermoautotrophicum was grown in continuous culture at 65 degrees C in a phosphate-limited medium at specific growth rates from 0.06 to 0.28 h-1 (maximum growth rate [mu max] = 0.36 h-1). Cyclic-2,3-diphosphoglycerate (cyclic DPG) levels ranged from 2 to 20 mM in Pi-limited cells, compared with about 30 mM in batch-grown cells. The Monod constant for Pi-limited growth was 5 nM. Pi uptake rates were determined by following the disappearance of 32Pi from the medium. Interrupting the H2 supply stopped the uptake of Pi and the release of organic phosphates. Little or no efflux of Pi occurred in the presence or absence of H2. Pi uptake of cells adapted to nanomolar Pi concentrations could be accounted for by the operation of one uptake system with an apparent Km of about 25 nM and a Vmax of 58 nmol of Pi per min per g (dry weight). Uptake curves at 30 microM Pi or above were biphasic due to a sevenfold decrease in Vmax after an initial phase of rapid movement of Pi into the cell. Under these conditions the growth rate slowed to zero and the cyclic DPG pool expanded before growth resumed. Thus, three properties of M. thermoautotrophicum make it well adapted to live in a low-P environment: the presence of a low-Km, high-Vmax uptake system for Pi; the ability to accumulate cyclic DPG rapidly; and a growth strategy in which accumulation of Pi and cyclic DPG takes precedence over a shift-up in growth rate when excess Pi becomes available.

Control rod drive hydraulic system

DOEpatents

Ose, Richard A.

1992-01-01

A hydraulic system for a control rod drive (CRD) includes a variable output-pressure CR pump operable in a charging mode for providing pressurized fluid at a charging pressure, and in a normal mode for providing the pressurized fluid at a purge pressure, less than the charging pressure. Charging and purge lines are disposed in parallel flow between the CRD pump and the CRD. A hydraulic control unit is disposed in flow communication in the charging line and includes a scram accumulator. An isolation valve is provided in the charging line between the CRD pump and the scram accumulator. A controller is operatively connected to the CRD pump and the isolation valve and is effective for opening the isolation valve and operating the CRD pump in a charging mode for charging the scram accumulator, and closing the isolation valve and operating the CRD pump in a normal mode for providing to the CRD through the purge line the pressurized fluid at a purge pressure lower than the charging pressure.

40 CFR 420.134 - New source performance standards (NSPS).

Code of Federal Regulations, 2010 CFR

2010-07-01

... Source Performance Standards (NSPS) Pollutant Maximum daily 1 Maximum monthly avg. 1 TSS 0.00998 0.00465... operations. Subpart M—New Source Performance Standards (NSPS) Pollutant Maximum daily 1 Maximum monthly avg...

40 CFR 420.134 - New source performance standards (NSPS).

Code of Federal Regulations, 2011 CFR

2011-07-01

... Source Performance Standards (NSPS) Pollutant Maximum daily 1 Maximum monthly avg. 1 TSS 0.00998 0.00465... operations. Subpart M—New Source Performance Standards (NSPS) Pollutant Maximum daily 1 Maximum monthly avg...

Enhanced sludge reduction in septic tanks by increasing temperature.

PubMed

Pussayanavin, Tatchai; Koottatep, Thammarat; Eamrat, Rawintra; Polprasert, Chongrak

2015-01-01

Septic tanks in most developing countries are constructed without drainage trenches or leaching fields to treat toilet wastewater and /or grey water. Due to the short hydraulic retention time, effluents of these septic tanks are still highly polluted, and there is usually high accumulation of septic tank sludge or septage containing high levels of organics and pathogens that requires frequent desludging and subsequent treatment. This study aimed to reduce sludge accumulation in septic tanks by increasing temperatures of the septic tank content. An experimental study employing two laboratory-scale septic tanks fed with diluted septage and operating at temperatures of 40 and 30°C was conducted. At steady-state conditions, there were more methanogenic activities occurring in the sludge layer of the septic tank operating at the temperature of 40°C, resulting in less total volatile solids (TVS) or sludge accumulation and more methane (CH4) production than in the unit operating at 30°C. Molecular analysis found more abundance and diversity of methanogenic microorganisms in the septic tank sludge operating at 40°C than at 30°C. The reduced TVS accumulation in the 40°C septic tank would lengthen the period of septage removal, resulting in a cost-saving in desluging and septage treatment. Cost-benefit analysis of increasing temperatures in septic tanks was discussed.

Cadmium removal by Lemna minor and Spirodela polyrhiza.

PubMed

Chaudhuri, Devaleena; Majumder, Arunabha; Misra, Amal K; Bandyopadhyay, Kaushik

2014-01-01

The present study investigates the ability of two genus of duckweed (Lemna minor and Spirodela polyrhiza) to phytoremediate cadmium from aqueous solution. Duckweed was exposed to six different cadmium concentrations, such as, 0.5,1.0,1.5, 2.0, 2.5, and 3.0 mg/L and the experiment was continued for 22 days. Water samples were collected periodically for estimation of residual cadmium content in aqueous solution. At the end of treatment period plant samples were collected and accumulated cadmium content was measured. Cadmium toxicity was observed through relative growth factor and changes in chlorophyll content Experimental results showed that Lemna minor and Spirodela polyrhiza were capable of removing 42-78% and 52-75% cadmium from media depending upon initial cadmium concentrations. Cadmium was removed following pseudo second order kinetic model Maximum cadmium accumulation in Lemna minor was 4734.56 mg/kg at 2 mg/L initial cadmium concentration and 7711.00 mg/kg in Spirodela polyrhiza at 3 mg/L initial cadmium concentration at the end of treatment period. Conversely in both cases maximum bioconcentration factor obtained at lowest initial cadmium concentrations, i.e., 0.5 mg/L, were 3295.61 and 4752.00 for Lemna minor and Spirodela polyrhiza respectively. The present study revealed that both Lemna minor and Spirodela polyrhiza was potential cadmium accumulator.

Two-stage continuous operation of recombinant Escherichia coli using the bacteriophage lambda Q- vector.

PubMed

Oh, Jeong Seok; Cho, Daechul; Park, Tai Hyun

2005-11-01

A two-stage continuous culture of Escherichia coli in combination with a bacteriophage lambda system was performed in order to overcome the intrinsic plasmid instability that is frequently observed in recombinant fermentation. A phage lambda vector with a Q(-) mutation was used to enhance the expression of the lambda system. The optimal values of the important operational variables such as the substrate concentration, the dilution rate, and the mean residence time on the expression of the cloned gene were determined in both batch and continuous cultures. For all culturing modes, the full induction of the cloned gene was observed 4 h after the temperature shift. In the two stage continuous culture, the overproduction reached their maxima at D=0.25 h(-1) with 1.5 S(0) of the medium supply. The maximum productivity of the total beta-galactosidase was 16.3x10(6) U l(-1) h(-1), which was approximately seven times higher than that in the single-copy lysogenic stage. The recombinant cells were stable in the lysogenic state for more than 260 h, while they were stable for 40 h in the lytic state. The instability that developed rapidly in the second tank is believed to be due to the accumulation of lysis proteins as a result of vector leakage during the operation.

Influence of mining-related activities on concentrations of metals in water and sediment from streams of the Black Hills, South Dakota.

PubMed

May, T W; Wiedmeyer, R H; Gober, J; Larson, S

2001-01-01

Water and sediment samples were collected from streams in Spearfish Creek, Whitewood Creek, and Bear Butte Creek watersheds in the Black Hills, SD, an area impacted by gold mining operations. Arsenic concentrations that exceeded the U.S. Environmental Protection Agency's Maximum Concentration Limit of 50 microg/L for drinking water were found in water from Annie Creek, a tributary of Spearfish Creek, and from Whitewood Creek. Gold Run, a tributary of Whitewood Creek, and Annie Creek contained Se concentrations in water that exceeded the EPA Ecotox threshold of 5 microg/L and were classified as a high hazard for Se accumulation from water into the planktonic food chain and for resultant toxicity to fish and aquatic birds. Concentrations of As, Cd, Cu, Hg, Ni, Pb, and Zn in sediment exceeded EPA Ecotox thresholds in one or more of the watersheds suggesting potential adverse ecological effects. Sediment from Rubicon Creek, a tributary of Spearfish Creek, contained Se concentrations high enough (4.0 microg/g) to be a moderate hazard for accumulation from sediments into the benthic food chain, with resultant dietary toxicity to fish and aquatic birds. These results are discussed in light of historical mining activities and recent clean-up and reclamation efforts. Based on the results and comparisons to Ecotox tresholds, further studies of ecological effects are warranted.

Influence of mining-related activities on concentrations of metals in water and sediment from streams of the Black Hills, South Dakota

USGS Publications Warehouse

May, T.W.; Wiedmeyer, Ray H.; Gober, J.; Larson, S.

2001-01-01

Water and sediment samples were collected from streams in Spearfish Creek, Whitewood Creek, and Bear Butte Creek watersheds in the Black Hills, SD, an area impacted by gold mining operations. Arsenic concentrations that exceeded the U.S. Environmental Protection Agency's Maximum Concentration Limit of 50 μg/L for drinking water were found in water from Annie Creek, a tributary of Spearfish Creek, and from Whitewood Creek. Gold Run, a tributary of Whitewood Creek, and Annie Creek contained Se concentrations in water that exceeded the EPA Ecotox threshold of 5 μg/L and were classified as a high hazard for Se accumulation from water into the planktonic food chain and for resultant toxicity to fish and aquatic birds. Concentrations of As, Cd, Cu, Hg, Ni, Pb, and Zn in sediment exceeded EPA Ecotox thresholds in one or more of the watersheds suggesting potential adverse ecological effects. Sediment from Rubicon Creek, a tributary of Spearfish Creek, contained Se concentrations high enough (4.0 μg/g) to be a moderate hazard for accumulation from sediments into the benthic food chain, with resultant dietary toxicity to fish and aquatic birds. These results are discussed in light of historical mining activities and recent clean-up and reclamation efforts. Based on the results and comparisons to Ecotox tresholds, further studies of ecological effects are warranted.

Heavy metals accumulation in wood tissues of the forest-forming species growed in the Steppe technogenic landscapes in Ukraine

NASA Astrophysics Data System (ADS)

Lovinska, Viktoriia; Wiche, Oliver

2016-04-01

Territory of Steppe in Ukraine is affected by significant anthropogenic impact caused with mining, metallurgical, chemicalplants and heat power stations. The priority pollutants of the region emissions of these enterprises are presented such heavy metals as Cd, Pb, Cu, Zn, Ni, Mn. The regional forest ecosystems can be considered as potential concentrators of pollutants borned with different technogenic impact. It is necessary to study an ability of forests wood to accumulate heavy metals because accumulated toxins are eliminated from biogeochemical cycle in forest ecosystem for a long time. This study goal is to determine the accumulation properties of forest-forming species - Pinus sylvestris (Scots pine) and Robinia pseudoacacia (black locust) difference age group in relation to heavy metals. It was considerable also to assess the heavy metal distribution in the wood tissue of referred species.Heavy metals content were determined with atomic absorption spectrophotometer using. Scots pine and black locust are the main forest-forming species of natural and artificial forests within Northern Steppe.They can be seen as transformers of the heavy metals cycle and selective concentrators of toxic elements, under the conditions of their excessive concentrations in the environment.It was established that wood tissue of Scots pine and black locust accumulated cadmium in high concentrations according to the age in both species. Indexes of zinc accumulation in the wood of Scots pine exceeded the maximal value in the wood tissue of black locust. The results of our research demonstrated antagonistic interaction of cadmium and zinc. The highest copper concentrations was found for the trees at the age of 45 years. Lead has been identified in wood sample of all ages. Accumulation maximum was fixed in the oldest samples. The trend of concentration increasing of metal didn't find for both species. As for nickel there was established the opposite tendention for both studied species. Nickel maximum accumulation in black locust was fixed for the youngest copies. The same tendency was observed for Scots pine in copies of 45 years old. We did not see relation with age for mangan content in both studied species. The absolute value of the amount of mangan for Scots pine is much higher comparatevelly to black locust.

Effects on fatigue life of gate valves due to higher torque switch settings during operability testing

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

Richins, W.D.; Snow, S.D.; Miller, G.K.

1995-12-01

Some motor operated valves now have higher torque switch settings due to regulatory requirements to ensure valve operability with appropriate margins at design basis conditions. Verifying operability with these settings imposes higher stem loads during periodic inservice testing. These higher test loads increase stresses in the various valve internal parts which may in turn increase the fatigue usage factors. This increased fatigue is judged to be a concern primarily in the valve disks, seats, yokes, stems, and stem nuts. Although the motor operators may also have significantly increased loading, they are being evaluated by the manufacturers and are beyond themore » scope of this study. Two gate valves representative of both relatively weak and strong valves commonly used in commercial nuclear applications were selected for fatigue analyses. Detailed dimensional and test data were available for both valves from previous studies at the Idaho National Engineering Laboratory. Finite element models were developed to estimate maximum stresses in the internal parts of the valves and to identity the critical areas within the valves where fatigue may be a concern. Loads were estimated using industry standard equations for calculating torque switch settings prior and subsequent to the testing requirements of USNRC Generic Letter 89--10. Test data were used to determine both; (1) the overshoot load between torque switch trip and final seating of the disk during valve closing and (2) the stem thrust required to open the valves. The ranges of peak stresses thus determined were then used to estimate the increase in the fatigue usage factors due to the higher stem thrust loads. The usages that would be accumulated by 100 base cycles plus one or eight test cycles per year over 40 and 60 years of operation were calculated.« less

Growth of the eye lens: II. Allometric studies.

PubMed

Augusteyn, Robert C

2014-01-01

The purpose of this study was to examine the ontogeny and phylogeny of lens growth in a variety of species using allometry. Data on the accumulation of wet and/or dry lens weight as a function of bodyweight were obtained for 40 species and subjected to allometric analysis to examine ontogenic growth and compaction. Allometric analysis was also used to compare the maximum adult lens weights for 147 species with the maximum adult bodyweight and to compare lens volumes calculated from wet and dry weights with eye volumes calculated from axial length. Linear allometric relationships were obtained for the comparison of ontogenic lens and bodyweight accumulation. The body mass exponent (BME) decreased with increasing animal size from around 1.0 in small rodents to 0.4 in large ungulates for both wet and dry weights. Compaction constants for the ontogenic growth ranged from 1.00 in birds and reptiles up to 1.30 in mammals. Allometric comparison of maximum lens wet and dry weights with maximum bodyweights also yielded linear plots with a BME of 0.504 for all warm blooded species except primates which had a BME of 0.25. When lens volumes were compared with eye volumes, all species yielded a scaling constant of 0.75 but the proportionality constants for primates and birds were lower. Ontogenic lens growth is fastest, relative to body growth, in small animals and slowest in large animals. Fiber cell compaction takes place throughout life in most species, but not in birds and reptiles. Maximum adult lens size scales with eye size with the same exponent in all species, but birds and primates have smaller lenses relative to eye size than other species. Optical properties of the lens are generated through the combination of variations in the rate of growth, rate of compaction, shape and size.

78 FR 7768 - Public Service Company of Colorado; Notice of Application Accepted for Filing, Soliciting Motions...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-04

... project. The normal daily operation cycle involves pumping water from the lower reservoir to the upper... acre upper reservoir with 1,087 acre-feet of usable storage between the maximum operating elevation of... lower reservoir with 1,221 acre-feet of usable storage between the maximum operating elevation of 10,002...

Assessment of neutron skyshine near unmodified Accumulator Debuncher storage rings under Mu2e operational conditions

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

Cossairt, J.Donald; /Fermilab

2010-12-01

Preliminary plans for providing the proton beam needed by the proposed Mu2e experiment at Fermilab will require the transport of 8 GeV protons to the Accumulator/Debuncher where they be processed into an intensity and time structure useful for the experiment. The intensities involved are far greater that those encountered with antiprotons of the same kinetic energy in the same beam enclosures under Tevatron Collider operational conditions, the operating parameters for which the physical facilities of the Antiproton Source were designed. This note explores some important ramifications of the proposed operation for radiation safety and demonstrates the need for extensive modificationsmore » of significant portions of the shielding of the Accumulator Debuncher storage rings; notably that underneath the AP Service Buildings AP10, AP30, and AP50. While existing shielding is adequate for the current operating mode of the Accumulator/Debuncher as part of the Antiproton Source used in the Tevatron Collider program, without significant modifications of the shielding configuration in the Accumulator/Debuncher region and/or beam loss control systems far more effective than seen in most applications at Fermilab, the proposed operational mode for Mu2e is not viable for the following reasons: 1. Due to skyshine alone, under normal operational conditions large areas of the Fermilab site would be exposed to unacceptable levels of radiation where most of the Laboratory workforce and some members of the general public who regularly visit Fermilab would receive measurable doses annually, contrary to workforce, public, and DOE expectations concerning the As Low as Reasonably Achievable (ALARA) principle. 2. Under normal operational conditions, a sizeable region of the Fermilab site would also require fencing due to skyshine. The size of the areas involved would likely invite public inquiry about the significant and visible enlargement of Fermilab's posted radiological areas. 3. There would be aesthetics questions about the employment of so much new fencing on the Fermilab site. 4. The assumption of only 1.0% 'normal condition' beam losses over the three locations is regarded as being extremely optimistic. Thus, it is evident that it is necessary to pursue shielding improvements to support viable operation of the Mu2e experiment.« less

Uptake and distribution of minerals and heavy metals in commonly grown leafy vegetable species irrigated with sewage water.

PubMed

Anwar, Sumera; Nawaz, Muhammad Farrakh; Gul, Sadaf; Rizwan, Muhammad; Ali, Shafaqat; Kareem, Arshaad

2016-09-01

Heavy metal uptake and accumulation behavior in dietary vegetables irrigated with sewage waters is an important issue worldwide. The main objective of this study was to examine and compare the physiological and growth responses of leafy vegetables irrigated with sewage water. A pot experiment was conducted in a wire house with three leafy vegetables, coriander (Coriandrum sativum), mint (Mentha arvensis), and fenugreek (Trigonella foenum), grown under ambient conditions. Plants were irrigated with different concentrations, 0, 50 (T 1), and 100 % (T 2), of sewage water. After harvesting, morphological and physiological parameters of plants were measured. Heavy metal (Cd, Cu, Pb, and Zn) concentrations in the sewage water were found much higher than safer limits. The results revealed that the highest plant biomass and lowest metal contents were observed in control treatments in all studied vegetables. The biomass of all the vegetables were negatively affected when irrigated with sewage water. In T 2, coriander accumulated maximum Cd (μg g(-1) DW) in shoots (4.97) as compared to other vegetables. The maximum Pb and Cu concentrations were accumulated in mint roots (44 and 3.9, respectively) as compared to coriander and fenugreek. Zinc was accumulated in the sequence of leaves > roots > shoots under polluted water irrigation. The concentrations of potassium increased in leaves, shoots, and roots in all vegetables, while phosphorous concentrations varied with species and plant parts with increasing sewage water concentration. It was found that the leafy vegetables grown with sewage water irrigation may cause severe human health problems.

Pedogenic silica accumulation in chronosequence soils, southern California

USGS Publications Warehouse

Kendrick, K.J.; Graham, R.C.

2004-01-01

Chronosequential analysis of soil properties has proven to be a valuable approach for estimating ages of geomorphic surfaces where no independent age control exists. In this study we examined pedogenic silica as an indicator of relative ages of soils and geomorphic surfaces, and assessed potential sources of the silica. Pedogenic opaline silica was quantified by tiron (4,5-dihydroxy-1,3-benzene-disulfonic acid [disodium salt], C6H 4Na2O8S2) extraction for pedons in two different chromosequences in southern California, one in the San Timoteo Badlands and one in Cajon Pass. The soils of hoth of these chronosequences are developed in arkosic sediments and span 11.5 to 500 ka. The amount of pedogenic silica increases with increasing duration of pedogenesis, and the depth of the maximum silica accumulation generally coincides with the maximum expression of the argillic horizon. Pedogenic silica has accumulated in all of the soils, ranging from 1.2% tiron-extractable Si (Sitn) in the youngest soil to 4.6% in the oldest. Primary Si decreases with increasing duration of weathering, particularly in the upper horizons, where weathering conditions are most intense. The loss of Si coincides with the loss of Na and K, implicating the weathering of feld-spars as the likely source of Si loss. The quantity of Si lost in the upper horizons is adequate to account for the pedogenic silica accumulation in the subsoil. Pedogenic silica was equally effective as pedogenic Fe oxides as an indicator of relative soil age in these soils.

Optimization of Culture Parameters for Maximum Polyhydroxybutyrate Production by Selected Bacterial Strains Isolated from Rhizospheric Soils.

PubMed

Lathwal, Priyanka; Nehra, Kiran; Singh, Manpreet; Jamdagni, Pragati; Rana, Jogender S

2015-01-01

The enormous applications of conventional non-biodegradable plastics have led towards their increased usage and accumulation in the environment. This has become one of the major causes of global environmental concern in the present century. Polyhydroxybutyrate (PHB), a biodegradable plastic is known to have properties similar to conventional plastics, thus exhibiting a potential for replacing conventional non-degradable plastics. In the present study, a total of 303 different bacterial isolates were obtained from soil samples collected from the rhizospheric area of three crops, viz., wheat, mustard and sugarcane. All the isolates were screened for PHB (Poly-3-hydroxy butyric acid) production using Sudan Black staining method, and 194 isolates were found to be PHB positive. Based upon the amount of PHB produced, the isolates were divided into three categories: high, medium and low producers. Representative isolates from each category were selected for biochemical characterization; and for optimization of various culture parameters (carbon source, nitrogen source, C/N ratio, different pH, temperature and incubation time periods) for maximizing PHB accumulation. The highest PHB yield was obtained when the culture medium was supplemented with glucose as the carbon source, ammonium sulphate at a concentration of 1.0 g/l as the nitrogen source, and by maintaining the C/N ratio of the medium as 20:1. The physical growth parameters which supported maximum PHB accumulation included a pH of 7.0, and an incubation temperature of 30 degrees C for a period of 48 h. A few isolates exhibited high PHB accumulation under optimized conditions, thus showing a potential for their industrial exploitation.

Native granule associated short chain length polyhydroxyalkanoate synthase from a marine derived Bacillus sp. NQ-11/A2.

PubMed

Prabhu, Nimali N; Santimano, Maria Celisa; Mavinkurve, Suneela; Bhosle, Saroj N; Garg, Sandeep

2010-01-01

A rapidly growing marine derived Bacillus sp. strain NQ-11/A2, identified as Bacillus megaterium, accumulated 61% polyhydroxyalkanoate by weight. Diverse carbon sources served as substrates for the accumulation of short chain length polyhydroxyalkanoate. Three to nine granules either single or attached as buds could be isolated intact from each cell. Maximum activity of polyhydroxyalkanoate synthase was associated with the granules. Granule-bound polyhydroxyalkanoate synthase had a K(m) of 7.1 x 10(-5) M for DL-beta-hydroxybutyryl-CoA. Temperature and pH optima for maximum activity were 30 degrees C and 7.0, respectively. Sodium ions were required for granule-bound polyhydroxyalkanoate synthase activity and inhibited by potassium. Granule-bound polyhydroxyalkanoate synthase was apparently covalently bound to the polyhydroxyalkanoate-core of the granules and affected by the chaotropic reagent urea. Detergents inhibited the granule-bound polyhydroxyalkanoate synthase drastically whilst glycerol and bovine serum albumin stabilized the synthase.

Opioid agonists binding and responses in SH-SY5Y cells

NASA Technical Reports Server (NTRS)

Costa, E. M.; Hoffmann, B. B.; Loew, G. H.

1992-01-01

SH-SY5Y (human neuroblastoma) cultured cells, known to have mu-opioid receptors, have been used to assess and compare the ability of eight representative mu-selective compounds from diverse opioid families to recognize and activate these receptors. A wide range of receptor affinities spanning a factor of 10,000 was found between the highest affinity fentanyl analogs (Ki = 0.1nM) and the lowest affinity analog, meperidine (Ki = 1 microM). A similar range was found for inhibition of PGE1-stimulated cAMP accumulation with a rank order of activities that closely paralleled binding affinities. Maximum inhibition of cAMP accumulation by each compound was about 80%. Maximum stimulation of GTPase activity (approximately 50%) was also similar for all compounds except the lowest affinity meperidine. Both effects were naloxone reversible. These results provide further evidence that mu-receptors are coupled to inhibition of adenylate cyclase and that the SH-SY5Y cell line is a good system for assessment of mu-agonists functional responses.

Utilization of heavy metal-rich tannery sludge for sweet basil (Ocimum basilicum L.) cultivation.

PubMed

Chand, Sukhmal; Singh, Shweta; Singh, Vinay Kumar; Patra, D D

2015-05-01

Unlike food crops, essential oil-bearing crops in which the oil is extracted through hydro-distillation can be a suitable crop to be grown in heavy metal-polluted soils as the oil does not carry any heavy metal. In a field experiment conducted at CIMAP, Lucknow, India during 2011 and 2012, influence of six doses of tannery sludge viz 0, 10, 20, 30, 40, and 50 t ha(-1) were tested, taking sweet basil (Ocimum basilicum) as the test crop. Maximum herb yield was obtained with the application of sludge at 20 t ha(-1). While in root, accumulation of Cd and Pb increased significantly up to 20 t ha(-1), Cr accumulation increased with increasing the dose of tannery sludge reaching maximum at 50 t ha(-1). Essential oil yield of basil (Ocimum basilicum) was significantly affected due to sludge application. Quality of essential oil, in term of chemical constituents, however, was marginally influenced due to tannery sludge application.

Predictive modelling of JT-60SA high-beta steady-state plasma with impurity accumulation

NASA Astrophysics Data System (ADS)

Hayashi, N.; Hoshino, K.; Honda, M.; Ide, S.

2018-06-01

The integrated modelling code TOPICS has been extended to include core impurity transport, and applied to predictive modelling of JT-60SA high-beta steady-state plasma with the accumulation of impurity seeded to reduce the divertor heat load. In the modelling, models and conditions are selected for a conservative prediction, which considers a lower bound of plasma performance with the maximum accumulation of impurity. The conservative prediction shows the compatibility of impurity seeding with core plasma with high-beta (β N  >  3.5) and full current drive conditions, i.e. when Ar seeding reduces the divertor heat load below 10 MW m‑2, its accumulation in the core is so moderate that the core plasma performance can be recovered by additional heating within the machine capability to compensate for Ar radiation. Due to the strong dependence of accumulation on the pedestal density gradient, high separatrix density is important for the low accumulation as well as the low divertor heat load. The conservative prediction also shows that JT-60SA has enough capability to explore the divertor heat load control by impurity seeding in high-beta steady-state plasmas.

Soil water availability and capacity of nitrogen accumulation influence variations of intrinsic water use efficiency in rice.

PubMed

Xue, Wei; Nay-Htoon, Bhone; Lindner, Steve; Dubbert, Maren; Otieno, Dennis; Ko, Jonghan; Werner, Christiane; Tenhunen, John

2016-04-01

Leaf intrinsic water use efficiency (WUEi) coupling maximum assimilation rate (Amax) and transpirable water lost via stomatal conductance (gsc) has been gaining increasing concern in sustainable crop production. Factors that influence leaf Amax and WUEi in rice (Oryza sativa L. cv Unkang) at flooding and rainfed conditions were evaluated. Positive correlations for leaf nitrogen content (Nm) and maximum carboxylation rate (Vcmax), for nitrogen allocation in Rubisco enzymes and mesophyll conductance (gm) were evident independent of cropping cultures. Rainfed rice exhibited enriched canopy leaf average Nm resulting in higher Amax, partially supporting improved leaf WUEi. Maximum WUEi (up to 0.14 μmol mmol(-1)) recorded in rainfed rice under drought conditions resulted from increasing gm/gsc ratio while at cost of significant decline in Amax due to hydraulically constrained gsc. Amax sensitivity related to gsc which was regulated by plant hydraulic conductance. WUEi was tightly correlated to Vcmax/gsc and gm/gsc ratios across the paddy and rainfed not to light environment, morphological and physiological traits, highlighting enhance capacity of Nm accumulation in rainfed rice with gsc at moderately high level similar to paddy rice facilitate optimization in Amax and WUEi while, is challenged by drought-vulnerable plant hydraulic conductance. Copyright © 2016 Elsevier GmbH. All rights reserved.

Schrödinger Operator with Non-Zero Accumulation Points of Complex Eigenvalues

NASA Astrophysics Data System (ADS)

Bögli, Sabine

2017-06-01

We study Schrödinger operators {H=-Δ + V} in {L2(Ω)} where {Ω} is R^d or the half-space R+d, subject to (real) Robin boundary conditions in the latter case. For {p > d} we construct a non-real potential {V \\in Lp(Ω) \\cap L^{∞}(Ω)} that decays at infinity so that H has infinitely many non-real eigenvalues accumulating at every point of the essential spectrum {σ_ess(H)=[0,∞)}. This demonstrates that the Lieb-Thirring inequalities for selfadjoint Schrödinger operators are no longer true in the non-selfadjoint case.

Complex matrix multiplication operations with data pre-conditioning in a high performance computing architecture

DOEpatents

Eichenberger, Alexandre E; Gschwind, Michael K; Gunnels, John A

2014-02-11

Mechanisms for performing a complex matrix multiplication operation are provided. A vector load operation is performed to load a first vector operand of the complex matrix multiplication operation to a first target vector register. The first vector operand comprises a real and imaginary part of a first complex vector value. A complex load and splat operation is performed to load a second complex vector value of a second vector operand and replicate the second complex vector value within a second target vector register. The second complex vector value has a real and imaginary part. A cross multiply add operation is performed on elements of the first target vector register and elements of the second target vector register to generate a partial product of the complex matrix multiplication operation. The partial product is accumulated with other partial products and a resulting accumulated partial product is stored in a result vector register.

26 CFR 1.707-0 - Table of contents.

Code of Federal Regulations, 2014 CFR

2014-04-01

... Rules Applicable to Guaranteed Payments, Preferred Returns, Operating Cash Flow Distributions, and...) Presumption regarding operating cash flow distributions. (1) In general. (2) Operating cash flow distributions. (i) In general. (ii) Operating cash flow safe harbor. (iii) Tiered partnerships. (c) Accumulation of...

26 CFR 1.707-0 - Table of contents.

Code of Federal Regulations, 2012 CFR

2012-04-01

... Rules Applicable to Guaranteed Payments, Preferred Returns, Operating Cash Flow Distributions, and...) Presumption regarding operating cash flow distributions. (1) In general. (2) Operating cash flow distributions. (i) In general. (ii) Operating cash flow safe harbor. (iii) Tiered partnerships. (c) Accumulation of...

26 CFR 1.707-0 - Table of contents.

Code of Federal Regulations, 2010 CFR

2010-04-01

... Guaranteed Payments, Preferred Returns, Operating Cash Flow Distributions, and Reimbursements of Preformation... operating cash flow distributions. (1) In general. (2) Operating cash flow distributions. (i) In general. (ii) Operating cash flow safe harbor. (iii) Tiered partnerships. (c) Accumulation of guaranteed...

26 CFR 1.707-0 - Table of contents.

Code of Federal Regulations, 2013 CFR

2013-04-01

... Rules Applicable to Guaranteed Payments, Preferred Returns, Operating Cash Flow Distributions, and...) Presumption regarding operating cash flow distributions. (1) In general. (2) Operating cash flow distributions. (i) In general. (ii) Operating cash flow safe harbor. (iii) Tiered partnerships. (c) Accumulation of...

26 CFR 1.707-0 - Table of contents.

Code of Federal Regulations, 2011 CFR

2011-04-01

... Rules Applicable to Guaranteed Payments, Preferred Returns, Operating Cash Flow Distributions, and...) Presumption regarding operating cash flow distributions. (1) In general. (2) Operating cash flow distributions. (i) In general. (ii) Operating cash flow safe harbor. (iii) Tiered partnerships. (c) Accumulation of...

Antarctic Megadunes - Assessment of Topographic Form and Windward Progradation from ICESat Altimetry, 2003-2009

NASA Astrophysics Data System (ADS)

Shuman, C. A.; Scambos, T. A.; Fahnestock, M. A.; Suchdeo, V. P.

2011-12-01

More than 900,000 square kilometers of East Antarctica are covered by distinctive megadune features (Fahnestock et al., 2000, Courville et al., 2007) as first defined by Swithinbank (1988). These long, undulating, sinuous dunes are due to persistent gravity-driven katabatic winds and spatially variable accumulation. In the field, they have a distinctive morphology, but characterization of the evolution of these active landscape features requires detailed elevation data as well as radar backscatter and grain size information. In this study, we utilize NASA's ICESat laser altimetry data during 2003-2009 (corrected for intercampaign biases) in the vicinity of an NSF-OPP funded research site near 80.78°S, 124.5°E, occupied and instrumented during the 2002-2003 and 2003-2004 summer seasons with additional limited field observations from January 2011. Using remote sensing data sets and field observations, we can characterize these features including their extent, variability, and elevation change with time. Field measurements from ground penetrating radar, automatic weather stations, surface photos, snowpits, and shallow cores provide in situ and subsurface information on local dune structure. Based on these data, Antarctic megadunes can be characterized as linear strips of higher accumulation (~30 to 80 kg m-2 a-1 maximum, typically toward the lower part of the range) consisting of fine-grained, wind-packed snow, generally forming 2-8 meter high, 1-2 km wide ridges up to 100 km long and separated by 2-6 km of near-zero-accumulation wind glaze regions. Glaze surfaces overlie extremely metamorphosed firn composed of very coarse recrystallized grains with poorly expressed layering. Our study extends site-specific results summarized in Courville et al. (2007) across the megadune study area with co-located MODIS-based Mosaic of Antarctica (MOA) images and surface optical grain size (e.g. Scambos et al., 2007), calibrated SAR backscatter data from the Radarsat Antarctic Mapping Mission (RAMP; Jezek, 1999), and elevation profiles and derived elevation changes from ICESat. Megadunes form by windward accretion of snow from the blowing snow stream entrained in the katabatic layer (Frezzotti et al., 2002; Courville et al., 2007). Ground-penetrating radar profiles reveal that the accumulation rate and the surface profile shape are intimately related for megadunes, with peak accumulation at the maximum surface slope on the windward face. We infer from accumulation and slope data that active megadunes in the field study area should migrate to the windward at ~12.5 m a-1. This motion is somewhat offset in our study area by the GPS-measured ~4 m a-1 ice flow to the east at about 45 degrees to the mean wind azimuth. The region of maximum accumulation on the windward face should have a net thickening rate of up to 9 cm a-1 as the dune slowly shifts upwind (downwind areas should lower by somewhat smaller amounts). We detail ICESat elevation data across the study area for both accumulation and glaze areas of these dunes to attempt to document active migration.

Properties of the internal clock.

PubMed

Church, R M

1984-01-01

Evidence has been cited for the following properties of the parts of the psychological process used for timing intervals: The pacemaker has a mean rate that can be varied by drugs, diet, and stress. The switch has a latency to operate and it can be operated in various modes, such as run, stop, and reset. The accumulator times up, in absolute, arithmetic units. Working memory can be reset on command or, after lesions have been created in the fimbria fornix, when there is a gap in a signal. The transformation from the accumulator to reference memory is done with a multiplicative constant that is affected by drugs, lesions, and individual differences. The comparator uses a ratio between the value in the accumulator (or working memory) and reference memory. Finally, there must be multiple switch-accumulator modules to handle simultaneous temporal processing; and the psychological timing process may be used on some occasions and not on others.

Frequency distribution of lithium in leaves of Lycium andersonii

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

Romney, E.M.; Wallace, A.; Kinnear, J.

1977-01-01

Lycium andersonii A. Gray is an accumulator of Li. Assays were made of 200 samples of it collected from six different locations within the Northern Mojave Desert. Mean concentrations of Li varied from location to location and tended not to follow log/sub e/ normal distribution, and to follow a normal distribution only poorly. There was some negative skewness to the log/sub e/ distribution which did exist. The results imply that the variation in accumulation of Li depends upon native supply of Li. Possibly the Li supply and the ability of L. andersonii plants to accumulate it are both log/sub e/more » normally distributed. The mean leaf concentration of Li in all locations was 29 ..mu..g/g, but the maximum was 166 ..mu..g/g.« less

Ratcheting induced cyclic softening behaviour of 42CrMo4 steel

NASA Astrophysics Data System (ADS)

Kreethi, R.; Mondal, A. K.; Dutta, K.

2015-02-01

Ratcheting is an important field of fatigue deformation which happens under stress controlled cyclic loading of materials. The aim of this investigation is to study the uniaxial ratcheting behavior of 42CrMo4 steel in annealed condition, under various applied stresses. In view of this, stress controlled fatigue tests were carried out at room temperature up to 200 cycles using a servo-hydraulic universal testing machine. The results indicate that accumulation of ratcheting strain increases monotonically with increasing maximum applied stress however; the rate of strain accumulation attains a saturation plateau after few cycles. The investigated steel shows cyclic softening behaviour under the applied stress conditions. The nature of strain accumulation and cyclic softening has been discussed in terms of dislocation distribution and plastic damage incurred in the material.

PC index as a proxy of the solar wind energy that entered into the magnetosphere and energy accumulated in the magnetosphere

NASA Astrophysics Data System (ADS)

Troshichev, Oleg; Sormakov, Dmitry

The PC index has been approved by the International Association of Geomagnetism and Aeronomy (Merida, Mexico, 2013) as a new international index of magnetic activity. Application of the PC index as a proxy of a solar wind energy that entered into the magnetosphere determines a principal distinction of the PC index from AL and Dst indices, which are regarded as characteristics of the energy that realized in magnetosphere in form of substorms and magnetic storms. This conclusion is based on results of analysis of relationships between the polar cap magnetic activity (PC-index) and parameters of the solar wind, on the one hand, relationships between changes of PC and development of magnetospheric substorms (AL-index) and magnetic storms (Dst-index), on the other hand. In this study the relationships between the PC and Dst indices in course of more than 200 magnetic storms observed in epoch of solar maximum (1998-2004) have been examined for different classes of storms separated by their kind and intensity. Results of statistical analysis demonstrate that depression of geomagnetic field starts to develop as soon as PC index steadily excess the threshold level ~1.5 mV/m; the storm intensity (DstMIN) follows, with delay ~ 1 hour, the maximum of PC in course of the storm. Main features of magnetic storms are determined, irrespective of their class and intensity, by the accumulated-mean PC value (PCAM): storm is developed as long as PCAM increases, comes to maximal intensity when PCAM attains the maximum, and starts to decay as soon as PCAM value displays decline. The run of “anomalous” magnetic storm on January 21-22, 2005, lasting many hours (with intensity of ≈ -100 nT) under conditions of northward or close to zero BZ component, is perfectly governed by behavior of the accumulated-mean PCAM index and, therefore, this storm should be regarded as an ordinary phenomenon. The conclusion is made that the PC index provides the unique on-line information on solar wind energy that entered into magnetosphere and PCAM index provides information on energy that accumulated in the magnetosphere.

Durability and regeneration of activated carbon air-cathodes in long-term operated microbial fuel cells

NASA Astrophysics Data System (ADS)

Zhang, Enren; Wang, Feng; Yu, Qingling; Scott, Keith; Wang, Xu; Diao, Guowang

2017-08-01

The performance of activated carbon catalyst in air-cathodes in microbial fuel cells was investigated over one year. A maximum power of 1722 mW m-2 was produced within the initial one-month microbial fuel cell operation. The air-cathodes produced a maximum power >1200 mW m-2 within six months, but gradually became a limiting factor for the power output in prolonged microbial fuel cell operation. The maximum power decreased by 55% when microbial fuel cells were operated over one year due to deterioration in activated carbon air-cathodes. While salt/biofilm removal from cathodes experiencing one-year operation increased a limiting performance enhancement in cathodes, a washing-drying-pressing procedure could restore the cathode performance to its original levels, although the performance restoration was temporary. Durable cathodes could be regenerated by re-pressing activated carbon catalyst, recovered from one year deteriorated air-cathodes, with new gas diffusion layer, resulting in ∼1800 mW m-2 of maximum power production. The present study indicated that activated carbon was an effective catalyst in microbial fuel cell cathodes, and could be recovered for reuse in long-term operated microbial fuel cells by simple methods.

Determination of the Maximum Control Forces and Attainable Quickness in the Operation of Airplane Controls

NASA Technical Reports Server (NTRS)

Hertel, Heinrich

1930-01-01

This report is intended to furnish bases for load assumptions in the designing of airplane controls. The maximum control forces and quickness of operation are determined. The maximum forces for a strong pilot with normal arrangement of the controls is taken as 1.25 times the mean value obtained from tests with twelve persons. Tests with a number of persons were expected to show the maximum forces that a man of average strength can exert on the control stick in operating the elevator and ailerons and also on the rudder bar. The effect of fatigue, of duration and of the nature (static or dynamic) of the force, as also the condition of the test subject (with or without belt) were also considered.

Tephra fall clean-up in urban environments

NASA Astrophysics Data System (ADS)

Hayes, Josh L.; Wilson, Thomas M.; Magill, Christina

2015-10-01

Tephra falls impact urban communities by disrupting transport systems, contaminating and damaging buildings and infrastructures, and are potentially hazardous to human health. Therefore, prompt and effective tephra clean-up measures are an essential component of an urban community's response to tephra fall. This paper reviews case studies of tephra clean-up operations in urban environments around the world, spanning 50 years. It identifies methods used in tephra clean-up and assesses a range of empirical relationships between level of tephra accumulation and clean-up metrics such as collected tephra volume, costs, and duration of operations. Results indicate the volume of tephra collected from urban areas is proportional to tephra accumulation. Urban areas with small tephra accumulations (1,000 m3/km2 or an average of 1 mm thickness) may collect < 1% of the total deposit, whereas urban areas which experience large accumulations (> 50,000 m3/km2 or an average of 50 mm thickness) remove up to 80%. This relationship can inform impact and risk assessments by providing an estimate of the likely response required for a given tephra fall. No strong relationship was found between tephra fall accumulation and clean-up cost or duration for urban environments which received one-off tephra falls, suggesting that these aspects of tephra fall clean-up operations are context specific. Importantly, this study highlights the advantage of effective planning for tephra clean-up and disposal in potentially exposed areas.

Capabilities of GRO/OSSE for observing solar flares

NASA Technical Reports Server (NTRS)

Kurfess, J. D.; Johnson, W. N.; Share, G. H.; Hulburt, E. O.; Matz, S. M.; Murphy, R. J.

1989-01-01

The launch of the Gamma Ray Observatory (GRO) near solar maximum makes solar flare studies early in the mission particularly advantageous. The Oriented Scintillation Spectrometer Experiment (OSSE) on GRO, covering the energy range 0.05 to 150 MeV, has some significant advantages over the previous generation of satellite-borne gamma-ray detectors for solar observations. The OSSE detectors will have about 10 times the effective area of the Gamma-Ray Spectrometer (GRS) on Solar Maximum Mission (SMM) for both photons and high-energy neutrons. The OSSE also has the added capability of distinguishing between high-energy neutrons and photons directly. The OSSE spectral accumulation time (approx. 4s) is four times faster than that of the SMM/GRS; much better time resolution is available in selected energy ranges. These characteristics will allow the investigation of particle acceleration in flares based on the evolution of the continuum and nuclear line components of flare spectra, nuclear emission in small flares, the anisotropy of continuum emission in small flares, and the relative intensities of different nuclear lines. The OSSE observational program will be devoted primarily to non-solar sources. Therefore, solar observations require planning and special configurations. The instrumental and operational characteristics of OSSE are discussed in the context of undertaking solar observations. The opportunities for guest investigators to participate in solar flare studies with OSSE is also presented.

[Enniatin B synthesis by a Fusarium sambucinum Fuck culture].

PubMed

Minasian, A E; Chermenskiĭ, D N; Ellanskaia, I A

1978-01-01

Three fungal strains belonging to the genus Fusarium Lk. ex. Fr. (F. sambucinum Fuck. 52377, F. avenaceum (Fr. Sacc.) 52311, F. gibbosum App. et. Wr. emend Bilai 52021) whcih form 800-1200 mg of enniatin B per litre during submerged cultivation have been selected. The morphology of F. sambucinum 52377 in the course of growth and production of enniatin B on the selected medium is described. The maximum accumulation of the product is found at the stationary growth phase. The active accumulation of fatty inclusions during this period suggests the participation of metabolism of fatty acids in the biosynthesis of enniatin B.

Defense Science Board Summer Study on Autonomy

DTIC Science & Technology

2016-06-01

hours, at a maximum velocity of 40 mph, with a maximum payload of 9 kg (20 lbs); a maximum range of 160 km (100 miles); and can operate in wind /gust...existing mine disposal platform, such as Seafox, with contact reacquisition and neutralization capability. Seafox is a wire -guided mine neutralizer...functions, will retain operator control of neutralization and will remove the need for personnel to enter the minefield to execute fly- by- wire

Study of monolithic integrated solar blind GaN-based photodetectors

NASA Astrophysics Data System (ADS)

Wang, Ling; Zhang, Yan; Li, Xiaojuan; Xie, Jing; Wang, Jiqiang; Li, Xiangyang

2018-02-01

Monolithic integrated solar blind devices on the GaN-based epilayer, which can directly readout voltage signal, were fabricated and studied. Unlike conventional GaN-based photodiodes, the integrated devices can finish those steps: generation, accumulation of carriers and conversion of carriers to voltage. In the test process, the resetting voltage was square wave with the frequency of 15 and 110 Hz, its maximal voltage of ˜2.5 V. Under LEDs illumination, the maximum of voltage swing is about 2.5 V, and the rise time of voltage swing from 0 to 2.5 V is only about 1.6 ms. However, in dark condition, the node voltage between detector and capacitance nearly decline to zero with time when the resetting voltage was equal to zero. It is found that the leakage current in the circuit gives rise to discharge of the integrated charge. Storage mode operation can offer gain, which is advantage to detection of weak photo signal.

Enhanced microbial reduction of vanadium (V) in groundwater with bioelectricity from microbial fuel cells

NASA Astrophysics Data System (ADS)

Hao, Liting; Zhang, Baogang; Tian, Caixing; Liu, Ye; Shi, Chunhong; Cheng, Ming; Feng, Chuanping

2015-08-01

Bioelectricity generated from the microbial fuel cell (MFC) is applied to the bioelectrical reactor (BER) directly to enhance microbial reduction of vanadium (V) (V(V)) in groundwater. With the maximum power density of 543.4 mW m-2 from the MFC, V(V) removal is accelerated with efficiency of 93.6% during 12 h operation. Higher applied voltage can facilitate this process. V(V) removals decrease with the increase of initial V(V) concentration, while extra addition of chemical oxygen demand (COD) has little effect on performance improvement. Microbial V(V) reduction is enhanced and then suppressed with the increase of conductivity. High-throughput 16S rRNA gene pyrosequencing analysis implies the accumulated Enterobacter and Lactococcus reduce V(V) with products from fermentative microorganisms such as Macellibacteroides. The presentation of electrochemically active bacteria as Enterobacter promotes electron transfers. This study indicates that application of bioelectricity from MFCs is a promising strategy to improve the efficiency of in-situ bioremediation of V(V) polluted groundwater.

Photon-induced tunability of the thermospin current in a Rashba ring

NASA Astrophysics Data System (ADS)

Abdullah, Nzar Rauf; Arnold, Thorsten; Tang, Chi-Shung; Manolescu, Andrei; Gudmundsson, Vidar

2018-04-01

The goal of this work is to show how the thermospin polarization current in a quantum ring changes in the presence of Rashba spin-orbit coupling and a quantized single photon mode of a cavity the ring is placed in. Employing the reduced density operator and a general master equation formalism, we find that both the Rashba interaction and the photon field can significantly modulate the spin polarization and the thermospin polarization current. Tuning the Rashba coupling constant, degenerate energy levels are formed corresponding to the Aharonov-Casher destructive phase interference in the quantum ring system. Our analysis indicates that the maximum spin polarization can be observed at the points of degenerate energy levels due to spin accumulation in the system without the photon field. The thermospin current is thus suppressed. In the presence of the cavity, the photon field leads to an additional kinetic momentum of the electron. As a result the spin polarization can be enhanced by the photon field.

14 CFR 23.1583 - Operating limitations.

Code of Federal Regulations, 2012 CFR

2012-01-01

...) The maximum zero wing fuel weight, where relevant, as established in accordance with § 23.343. (d... passenger seating configuration. The maximum passenger seating configuration. (k) Allowable lateral fuel loading. The maximum allowable lateral fuel loading differential, if less than the maximum possible. (l...

14 CFR 23.1524 - Maximum passenger seating configuration.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Maximum passenger seating configuration. 23.1524 Section 23.1524 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Operating Limitations and Information § 23.1524 Maximum passenger seating configuration. The maximum...

Determinants of reinforcer accumulation during an operant task.

PubMed

McFarland, J M; Lattal, K A

2001-11-01

Responses by rats on an earn lever made available food pellets that were delivered to a food cup by responses on a second, collect, lever. The rats could either collect and immediately consume or accumulate (defined as the percentage of multiple earn responses and as the number of pellets earned before a collect response) earned pellets. In Experiment 1, accumulation varied as a function of variations in the earn or collect response requirements and whether the earn and collect levers were proximal (31 cm) or distal (248 cm) to one another. Some accumulation occurred under all but one of the conditions, but generally was higher when the earn and collect levers were distal to one another, particularly when the earn response requirement was fixed-ratio (FR) 1. In Experiment 2, the contributions of responses and time to accumulation were assessed by comparing an FR 20 earn response requirement to a condition in which only a single earn response was required at the end of a time interval nominally yoked to the FR interval. When 248 cm separated the earn and collect levers, accumulation was always greater in the FR condition, and it was not systematically related to reinforcement rate. In Experiment 3, increasing the earn response requirement with a progressive-ratio schedule that reset only with a collect response increased the likelihood of accumulation when the collect and earn levers were 248 cm apart, even though such accumulation increased the next earn response requirement. Reinforcer accumulation is an understudied dimension of operant behavior that relates to the analysis of such phenomena as hoarding and self-control, in that they too involve accumulating versus immediately collecting or consuming reinforcers.

Determinants of reinforcer accumulation during an operant task.

PubMed Central

McFarland, J M; Lattal, K A

2001-01-01

Responses by rats on an earn lever made available food pellets that were delivered to a food cup by responses on a second, collect, lever. The rats could either collect and immediately consume or accumulate (defined as the percentage of multiple earn responses and as the number of pellets earned before a collect response) earned pellets. In Experiment 1, accumulation varied as a function of variations in the earn or collect response requirements and whether the earn and collect levers were proximal (31 cm) or distal (248 cm) to one another. Some accumulation occurred under all but one of the conditions, but generally was higher when the earn and collect levers were distal to one another, particularly when the earn response requirement was fixed-ratio (FR) 1. In Experiment 2, the contributions of responses and time to accumulation were assessed by comparing an FR 20 earn response requirement to a condition in which only a single earn response was required at the end of a time interval nominally yoked to the FR interval. When 248 cm separated the earn and collect levers, accumulation was always greater in the FR condition, and it was not systematically related to reinforcement rate. In Experiment 3, increasing the earn response requirement with a progressive-ratio schedule that reset only with a collect response increased the likelihood of accumulation when the collect and earn levers were 248 cm apart, even though such accumulation increased the next earn response requirement. Reinforcer accumulation is an understudied dimension of operant behavior that relates to the analysis of such phenomena as hoarding and self-control, in that they too involve accumulating versus immediately collecting or consuming reinforcers. PMID:11768714

Regional Greenland accumulation variability from Operation IceBridge airborne accumulation radar

NASA Astrophysics Data System (ADS)

Lewis, Gabriel; Osterberg, Erich; Hawley, Robert; Whitmore, Brian; Marshall, Hans Peter; Box, Jason

2017-03-01

The mass balance of the Greenland Ice Sheet (GrIS) in a warming climate is of critical interest to scientists and the general public in the context of future sea-level rise. An improved understanding of temporal and spatial variability of snow accumulation will reduce uncertainties in GrIS mass balance models and improve projections of Greenland's contribution to sea-level rise, currently estimated at 0.089 ± 0.03 m by 2100. Here we analyze 25 NASA Operation IceBridge accumulation radar flights totaling > 17 700 km from 2013 to 2014 to determine snow accumulation in the GrIS dry snow and percolation zones over the past 100-300 years. IceBridge accumulation rates are calculated and used to validate accumulation rates from three regional climate models. Averaged over all 25 flights, the RMS difference between the models and IceBridge accumulation is between 0.023 ± 0.019 and 0.043 ± 0.029 m w.e. a-1, although each model shows significantly larger differences from IceBridge accumulation on a regional basis. In the southeast region, for example, the Modèle Atmosphérique Régional (MARv3.5.2) overestimates by an average of 20.89 ± 6.75 % across the drainage basin. Our results indicate that these regional differences between model and IceBridge accumulation are large enough to significantly alter GrIS surface mass balance estimates. Empirical orthogonal function analysis suggests that the first two principal components account for 33 and 19 % of the variance, and correlate with the Atlantic Multidecadal Oscillation (AMO) and wintertime North Atlantic Oscillation (NAO), respectively. Regions that disagree strongest with climate models are those in which we have the fewest IceBridge data points, requiring additional in situ measurements to verify model uncertainties.

Abscisic Acid Accumulation by Roots of Xanthium strumarium L. and Lycopersicon esculentum Mill. in Relation to Water Stress.

PubMed

Cornish, K; Zeevaart, J A

1985-11-01

Plants of Xanthium strumarium L. and Lycopersicon esculentum Mill. cv ;Rheinlands Ruhm' were grown in solution culture, and control and steam-girdled intact plants were stressed. Detached roots of both species were stressed to different extents in two ways: (a) either in warm air or, (b) in the osmoticum Aquacide III. The roots of both species produced and accumulated progressively more abscisic acid (ABA), the greater the stress inflicted by either method. ABA-glucose ester levels in Xanthium roots were not affected by water stress and were too low to be the source of the stress-induced ABA. The fact that ABA accumulated in detached roots and in roots of girdled plants proves that ABA was synthesized in the roots and not merely transported from the shoots.Maximum ABA accumulation in detached roots occurred after 60 to 70% loss of fresh weight. In Xanthium roots, ABA levels continued to increase for at least 11 hours, and no catabolism was apparent when stressed roots were immersed in water, although the roots did stop accumulating ABA. When osmotically stressed, Xanthium roots reached a maximum ABA level after 2 hours, but ABA continued to rise in the medium.Under optimal stress conditions, endogenous ABA levels increased 100 times over their prestress values in detached roots of Xanthium, and 15 times in Lycopersicon under nonoptimal stress, when endogenous ABA was expressed as concentrations based on tissue water content. These are much greater relative increases than observed in the leaves (15 times in Xanthium, 3 times in Lycopersicon), although the roots contain substantially less ABA than the leaves in all circumstances. The results suggest that the endogenous level of ABA in roots could rise appreciably prior to leaf wilt, and could modify the plant's water economy before the leaves become stressed.

Abscisic Acid Accumulation by Roots of Xanthium strumarium L. and Lycopersicon esculentum Mill. in Relation to Water Stress 1

PubMed Central

Cornish, Katrina; Zeevaart, Jan A. D.

1985-01-01

Plants of Xanthium strumarium L. and Lycopersicon esculentum Mill. cv `Rheinlands Ruhm' were grown in solution culture, and control and steam-girdled intact plants were stressed. Detached roots of both species were stressed to different extents in two ways: (a) either in warm air or, (b) in the osmoticum Aquacide III. The roots of both species produced and accumulated progressively more abscisic acid (ABA), the greater the stress inflicted by either method. ABA-glucose ester levels in Xanthium roots were not affected by water stress and were too low to be the source of the stress-induced ABA. The fact that ABA accumulated in detached roots and in roots of girdled plants proves that ABA was synthesized in the roots and not merely transported from the shoots. Maximum ABA accumulation in detached roots occurred after 60 to 70% loss of fresh weight. In Xanthium roots, ABA levels continued to increase for at least 11 hours, and no catabolism was apparent when stressed roots were immersed in water, although the roots did stop accumulating ABA. When osmotically stressed, Xanthium roots reached a maximum ABA level after 2 hours, but ABA continued to rise in the medium. Under optimal stress conditions, endogenous ABA levels increased 100 times over their prestress values in detached roots of Xanthium, and 15 times in Lycopersicon under nonoptimal stress, when endogenous ABA was expressed as concentrations based on tissue water content. These are much greater relative increases than observed in the leaves (15 times in Xanthium, 3 times in Lycopersicon), although the roots contain substantially less ABA than the leaves in all circumstances. The results suggest that the endogenous level of ABA in roots could rise appreciably prior to leaf wilt, and could modify the plant's water economy before the leaves become stressed. PMID:16664467

Mercury accumulation and attenuation at a rapidly forming delta with a point source of mining waste

PubMed Central

Johnson, Bryce E.; Esser, Bradley K.; Whyte, Dyan C.; Ganguli, Priya M.; Austin, Carrie M.; Hunt, James R.

2009-01-01

The Walker Creek intertidal delta of Tomales Bay, California is impacted by a former mercury mine within the watershed. Eleven short sediment cores (10 cm length) collected from the delta found monomethylmercury (MMHg) concentrations ranging from 0.3 to 11.4 ng/g (dry wt.), with lower concentrations occurring at the vegetated marsh and upstream channel locations. Algal mats common to the delta’s sediment surface had MMHg concentrations ranging from 7.5 to 31.5 ng/g, and the top 1 cm of sediment directly under the mats had two times greater MMHg concentrations compared to adjacent locations without algal covering. Spatial trends in resident biota reflect enhanced MMHg uptake at the delta compared to other bay locations. Eighteen sediment cores, 1 to 2 meters deep, collected from the 1.2 km2 delta provide an estimate of a total mercury (Hg) inventory of 2500 ± 500 kg. Sediment Hg concentrations ranged from pre-mining background conditions of approximately 0.1 μg/g to a post-mining maximum of 5 μg/g. Sediment accumulation rates were determined from three sediment cores using measured differences of 137Cs activity. We estimate a pre-mining Hg accumulation of less than 20 kg/yr, and a period of maximum Hg accumulation in the 1970s and 1980s with loading rates greater than 50 kg/yr, corresponding to the failure of a tailings dam at the mine site. At the time of sampling (2003) over 40 kg/yr of Hg was still accumulating at the delta, indicating limited recovery. We attribute observed spatial evolution of elevated Hg levels to ongoing inputs and sediment re-working, and estimate the inventory of the anthropogenic fraction of total Hg to be at least 1500 ± 300 kg. We suggest ongoing sediment inputs and methylation at the deltaic surface support enhanced mercury levels for resident biota and transfer to higher trophic levels throughout the Bay. PMID:19539980

Low uptake affinity cultivars with biochar to tackle Cd-tainted rice--A field study over four rice seasons in Hunan, China.

PubMed

Chen, De; Guo, Hu; Li, Ruiyue; Li, Lianqing; Pan, Genxing; Chang, Andrew; Joseph, Stephen

2016-01-15

Biochar is becoming an environmentally friendly material for remediation of heavy metal contaminated soils and improving food safety. A field trial over four rice seasons was conducted to investigate the use of biochar and low Cd accumulating cultivars on Cd uptake in a heavy metal contaminated soil. Wheat straw derived biochar was applied at 0, 20 and 40 t ha(-1). Two rice cultivars with differing Cd accumulation abilities were selected in each season. The results showed that both biochar and low Cd affinity cultivars significantly reduced rice grain Cd accumulation. Biochar had no significant effect the first season but thereafter consistently reduced rice grain Cd by a maximum of 61, 86 and 57% over the next three seasons. Zn accumulation in the rice grains was not decreased by biochar application, although available soil Zn was sharply reduced (35-91%). Indica conventional rice cultivars had much lower Cd, but higher Zn and lower Cd/Zn ratios in the grain than indica hybrid cultivars. Biochar was more effective for mitigating grain Cd accumulation in low Cd affinity cultivars than in high affinity cultivars. Soil pH was sustainably increased (up to nearly 1 unit) while available Cd significantly decreased by a maximum of 85% after biochar addition. The translocation of Cd from rice roots to shoots was reduced from 20 to 80% by biochar. Low uptake affinity cultivars combined with biochar reduced late rice grain Cd concentration and Cd/Zn ratios by 69-80% and 72-80%, respectively. It indicated that the management of combining biochar and low Cd affinity cultivars should be an efficient way to remediate Cd contaminated rice paddies and reduce health risk associated with consuming rice from these soils. Copyright © 2015 Elsevier B.V. All rights reserved.

Mycorrhizal infection, phosphorus uptake, and phenology in Ranunculus adoneus: implications for the functioning of mycorrhizae in alpine systems.

PubMed

Mullen, R B; Schmidt, S K

1993-05-01

Phosphorus levels, phenology of roots and shoots, and development of vesicular arbuscular mycorrhizal (VAM) fungi were monitored for two years in natural populations of the perennial alpine herb, Ranunculus adoneus. The purpose of this study was to understand how phosphorus uptake relates to the phenology of R. adoneus and to ascertain whether arbusculus, fungal structures used for nutrient transfer, were present when maximum phosphorus accumulation was occurring. Arbuscules were only present for a few weeks during the growing season of R. adoneus and their presence corresponded with increased phosphorus accumulation in both the roots and shoots of R. adoneus. In addition, phosphorus accumulation and peaks in mycorrhizal development occurred well after plant reproduction and most plant growth had occurred. The late season accumulation of phosphorus by mycorrhizal roots of R. adoneus is stored for use during early season growth and flowering the following spring. In this way R. adoneus can flower before soils thaw and root or mycorrhizal nutrient uptake can occur.

An approach to bioassessment of water quality using diversity measures based on species accumulative curves.

PubMed

Xu, Guangjian; Zhang, Wei; Xu, Henglong

2015-02-15

Traditional community-based bioassessment is time-consuming because they rely on full species-abundance data of a community. To improve bioassessment efficiency, the feasibility of the diversity measures based on species accumulative curves for bioassessment of water quality status was studied based on a dataset of microperiphyton fauna. The results showed that: (1) the species accumulative curves well fitted the Michaelis-Menten equation; (2) the β- and γ-diversity, as well as the number of samples to 50% of the maximum species number (Michaelis-Menten constant K), can be statistically estimated based on the formulation; (3) the rarefied α-diversity represented a significant negative correlation with the changes in the nutrient NH4-N; and (4) the estimated β-diversity and the K constant were significantly positively related to the concentration of NH4-N. The results suggest that the diversity measures based on species accumulative curves might be used as a potential bioindicator of water quality in marine ecosystems. Copyright © 2014 Elsevier Ltd. All rights reserved.

Sewage Effluent Infiltrates Frozen Forest Soil

Treesearch

Alfred Ray Harris

1976-01-01

Secondarily treated sewage effluent, applied at the rate of 1 and 2 inches per week, infiltrated a frozen Sparta sand soil forested with jack pine and scrub oak. Maximum frost depth in treated plots averaged 60 cm and in check plots averages 35 cm. Nitrogen was mobile with some accumulation. Phosphorus was absorbed.

Climate-host mapping of Phytophthora ramorum, causal agent of sudden oak death

Treesearch

Glenn Fowler; Roger Magarey; Manuel Colunga

2006-01-01

Phytophthora ramorum infection was modeled using the NAPPFAST system for the conterminous United States. Parameters used to model P. ramorum infection were: leaf wetness, minimum temperature, optimum temperature and maximum temperature over a specified number of accumulated days. The model was used to create maps showing the...

Fertilization of Northern Hardwoods

Treesearch

R. Lea; D.G. Brockway

1986-01-01

Northern hardwoods grow over a considerable range of climatic and edaphic conditions and exhibit a wide range in productivity.Many northern hardwood forests are capable of high production relative to other forest types, but are often slow to reach maximum productivity because of low nutrient availability.Altering the patterns of biomass accumulation so that managers...

46 CFR 58.30-35 - Testing.

Code of Federal Regulations, 2010 CFR

2010-10-01

... components thereof shall be tested as required by this section. (b) Accumulators constructed as pressure... associated equipment components, including hydraulic steering gear, in lieu of being tested at the time of installation, may be shop tested by the manufacturer to 11/2 times the maximum allowable pressure of the system...

46 CFR 58.30-35 - Testing.

Code of Federal Regulations, 2012 CFR

2012-10-01

... components thereof shall be tested as required by this section. (b) Accumulators constructed as pressure... associated equipment components, including hydraulic steering gear, in lieu of being tested at the time of installation, may be shop tested by the manufacturer to 11/2 times the maximum allowable pressure of the system...

46 CFR 58.30-35 - Testing.

Code of Federal Regulations, 2011 CFR

2011-10-01

... components thereof shall be tested as required by this section. (b) Accumulators constructed as pressure... associated equipment components, including hydraulic steering gear, in lieu of being tested at the time of installation, may be shop tested by the manufacturer to 11/2 times the maximum allowable pressure of the system...

46 CFR 58.30-35 - Testing.

Code of Federal Regulations, 2014 CFR

2014-10-01

... components thereof shall be tested as required by this section. (b) Accumulators constructed as pressure... associated equipment components, including hydraulic steering gear, in lieu of being tested at the time of installation, may be shop tested by the manufacturer to 11/2 times the maximum allowable pressure of the system...

46 CFR 58.30-35 - Testing.

Code of Federal Regulations, 2013 CFR

2013-10-01

... components thereof shall be tested as required by this section. (b) Accumulators constructed as pressure... associated equipment components, including hydraulic steering gear, in lieu of being tested at the time of installation, may be shop tested by the manufacturer to 11/2 times the maximum allowable pressure of the system...

SETTING A GOAL FOR TPH THAT ELIMINATES FREE PRODUCT IN WELLS

EPA Science Inventory

The U.S. EPA expects that remedial action at UST sites will reduce free product in monitoring wells to the maximum extent practicable. How much active treatment is necessary to ensure that free product will not accumulate in a monitoring well? The concentration of TPH that will...

Thermodynamic analysis of steam-injected advanced gas turbine cycles

NASA Astrophysics Data System (ADS)

Pandey, Devendra; Bade, Mukund H.

2017-12-01

This paper deals with thermodynamic analysis of steam-injected gas turbine (STIGT) cycle. To analyse the thermodynamic performance of steam-injected gas turbine (STIGT) cycles, a methodology based on pinch analysis is proposed. This graphical methodology is a systematic approach proposed for a selection of gas turbine with steam injection. The developed graphs are useful for selection of steam-injected gas turbine (STIGT) for optimal operation of it and helps designer to take appropriate decision. The selection of steam-injected gas turbine (STIGT) cycle can be done either at minimum steam ratio (ratio of mass flow rate of steam to air) with maximum efficiency or at maximum steam ratio with maximum net work conditions based on the objective of plants designer. Operating the steam injection based advanced gas turbine plant at minimum steam ratio improves efficiency, resulting in reduction of pollution caused by the emission of flue gases. On the other hand, operating plant at maximum steam ratio can result in maximum work output and hence higher available power.

Implications of ground-deformation measurements across earth fissures in subsidence areas in the southwestern USA

USGS Publications Warehouse

Holzer, Thomas L.

2010-01-01

Ground deformation was monitored at earth fissures in areas of land subsidence induced by groundwater extraction in the southwestern United States. The ground deformation is consistent with the mechanism that fissures are caused by horizontal strains generated by bending of overburden in response to localized differential compaction. Subsidence profiles indicated that localized differential subsidence occurred across the fissures and that maximum convex-upward curvature was at the fissure. The overall shape of the profile stayed similar with time, and maximum curvature remained stationary at the fissure. Horizontal displacements were largest near the fissure, and generally were small to negligible away from the fissure. Maximum tensile horizontal strains were at the fissure and coincided with maximum curvature in the subsidence profiles. Horizontal tensile strain continued to accumulate at fissures after they formed with rates of opening ranging from 30 to 120 microstrain/year at fissures in Arizona.

Growth performance and biochemical responses of three rice (Oryza sativa L.) cultivars grown in fly-ash amended soil.

PubMed

Dwivedi, S; Tripathi, R D; Srivastava, S; Mishra, S; Shukla, M K; Tiwari, K K; Singh, R; Rai, U N

2007-02-01

The disposal of fly-ash (FA) from coal-fired power stations causes significant economic and environmental problems. Use of such contaminated sites for crop production and use of contaminated water for irrigation not only decreases crop productivity but also poses health hazards to humans due to accumulation of toxic metals in edible grains. In the present investigation, three rice cultivars viz., Saryu-52, Sabha-5204, and Pant-4 were grown in garden soil (GS, control) and various amendments (10%, 25%, 50%, 75% and 100%) of FA for a period of 90 days and effect on growth and productivity of plant was evaluated vis-a-vis metal accumulation in the plants. The toxicity of FA at higher concentration (50%) was reflected by the reduction in photosynthetic pigments, protein and growth parameters viz., plant height, root biomass, number of tillers, grain and straw weight. However, at lower concentrations (10-25%), FA enhanced growth of the plants as evident by the increase of studied growth parameters. The cysteine and non-protein thiol (NP-SH) content showed increase in their levels up to 100% FA as compared to control, however, maximum content was found at 25% FA in Saryu-52 and Pant-4 and at 50% FA in Sabha-5204. Accumulation of Fe, Si, Cu, Zn, Mn, Ni, Cd and As was investigated in roots, leaves and seeds of the plants. Fe accumulation was maximum in all the parts of plant followed by Si and both showed more translocation to leaves while Mn, Zn, Cu, Ni and Cd showed lower accumulation and most of the metal was confined to roots in all the three cultivars. As was accumulated only in leaves and was not found to be in detectable levels in roots and seeds. The metal accumulation order in three rice cultivars was Fe > Si > Mn > Zn > Ni > Cu > Cd > As in all the plant parts. The results showed that rice varieties Saryu-52 and Sabha-5204 were more tolerant and could show improved growth and yield in lower FA application doses as compared to Pant-4. Thus, Sabha-5204 and Saryu-52 are found suitable for cultivation in FA amended agricultural soils for better crop yields.

Estimate of Solar Maximum Using the 1-8 Angstrom Geostationary Operational Environmental Satellites X-Ray Measurements

DTIC Science & Technology

2014-12-12

AFRL-RV-PS- AFRL-RV-PS- TR-2015-0005 TR-2015-0005 ESTIMATE OF SOLAR MAXIMUM USING THE 1–8 Å GEOSTATIONARY OPERATIONAL ENVIRONMENTAL SATELLITES X... Geostationary Operational Environmental Satellites X-Ray Measurements (Postprint) 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 61102F 6...of the solar cycle through an analysis of the solar X-ray background. Our results are based on the NOAA Geostationary Operational Environmental

Ion funnel ion trap and process

DOEpatents

Belov, Mikhail E [Richland, WA; Ibrahim, Yehia M [Richland, WA; Clowers, Biran H [West Richland, WA; Prior, David C [Hermiston, OR; Smith, Richard D [Richland, WA

2011-02-15

An ion funnel trap is described that includes a inlet portion, a trapping portion, and a outlet portion that couples, in normal operation, with an ion funnel. The ion trap operates efficiently at a pressure of .about.1 Torr and provides for: 1) removal of low mass-to-charge (m/z) ion species, 2) ion accumulation efficiency of up to 80%, 3) charge capacity of .about.10,000,000 elementary charges, 4) ion ejection time of 40 to 200 .mu.s, and 5) optimized variable ion accumulation times. Ion accumulation with low concentration peptide mixtures has shown an increase in analyte signal-to-noise ratios (SNR) of a factor of 30, and a greater than 10-fold improvement in SNR for multiply charged analytes.

40 CFR 464.25 - Pretreatment standards for existing sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

...) EFFLUENT GUIDELINES AND STANDARDS METAL MOLDING AND CASTING POINT SOURCE CATEGORY Copper Casting... existing sources. (a) Casting Quench Operations. PSES Pollutant or pollutant property Maximum for any 1 day... monitoring) 1.2 0.399 (b) Direct Chill Casting Operations. PSES Pollutant or pollutant property Maximum for...

29 CFR 1918.85 - Containerized cargo operations.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Containerized cargo operations. (a) Container markings. Every intermodal container shall be legibly and permanently marked with: (1) The weight of the container when empty, in pounds; (2) The maximum cargo weight... maximum cargo weight, in pounds. (b) Container weight. No container shall be hoisted by any lifting...

29 CFR 1918.85 - Containerized cargo operations.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Containerized cargo operations. (a) Container markings. Every intermodal container shall be legibly and permanently marked with: (1) The weight of the container when empty, in pounds; (2) The maximum cargo weight... maximum cargo weight, in pounds. (b) Container weight. No container shall be hoisted by any lifting...

29 CFR 1918.85 - Containerized cargo operations.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Containerized cargo operations. (a) Container markings. Every intermodal container shall be legibly and permanently marked with: (1) The weight of the container when empty, in pounds; (2) The maximum cargo weight... maximum cargo weight, in pounds. (b) Container weight. No container shall be hoisted by any lifting...

29 CFR 1918.85 - Containerized cargo operations.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Containerized cargo operations. (a) Container markings. Every intermodal container shall be legibly and permanently marked with: (1) The weight of the container when empty, in pounds; (2) The maximum cargo weight... maximum cargo weight, in pounds. (b) Container weight. No container shall be hoisted by any lifting...

29 CFR 1918.85 - Containerized cargo operations.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Containerized cargo operations. (a) Container markings. Every intermodal container shall be legibly and permanently marked with: (1) The weight of the container when empty, in pounds; (2) The maximum cargo weight... maximum cargo weight, in pounds. (b) Container weight. No container shall be hoisted by any lifting...

Trace-element deposition in the Cariaco Basin, Venezuela Shelf, under sulfate-reducing conditions: a history of the local hydrography and global climate, 20 ka to the present

USGS Publications Warehouse

Piper, David Z.; Dean, Walter E.

2002-01-01

A sediment core from the Cariaco Basin on the Venezuelan continental shelf, which recovered sediment that has been dated back to 20 ka (thousand years ago), was examined for its major-element-oxide and trace-element composition. Cadmium (Cd), chromium (Cr), copper (Cu), molybdenum (Mo), nickel (Ni), vanadium (V), and zinc (Zn) can be partitioned between a siliciclastic, terrigenous-derived fraction and two seawater-derived fractions. The two marine fractions are (1) a biogenic fraction represented by nutrient trace elements taken up mostly in the photic zone by phytoplankton, and (2) a hydrogenous fraction that has been derived from bottom water via adsorption and precipitation reactions. This suite of trace elements contrasts with a second suite of trace elements—barium (Ba), cobalt (Co), gallium (Ga), lithium (Li), the rare-earth elements, thorium (Th), yttrium (Y), and several of the major-element oxides—that has had solely a terrigenous source. The partitioning scheme, coupled with bulk sediment accumulation rates measured by others, allows us to determine the accumulation rate of trace elements in each of the three sediment fractions and of the fractions themselves. The current export of organic matter from the photic zone, redox conditions and advection of bottom water, and flux of terrigenous debris into the basin can be used to calculate independently trace-element depositional rates. The calculated rates show excellent agreement with the measured rates of the surface sediment. This agreement supports a model of trace-element accumulation rates in the subsurface sediment that gives a 20-kyr history of upwelling into the photic zone (that is, primary productivity), bottom-water advection and redox, and provenance. Correspondence of extrema in the geochemical signals with global changes in sea level and climate demonstrates the high degree to which the basin hydrography and provenance have responded to the paleoceanographic and paleoclimatic regimes of the last 20 kyr. The accumulation rate of the marine fraction of Mo increased abruptly at about 14.8 ka (calendar years), from less than 0.5 µg cm-2 yr-1 to greater than 4 µg cm-2 yr-1. Its accumulation rate remained high but variable until 8.6 ka, when it decreased sharply to 1 µg cm-2 yr-1. It continued to decrease to 4.0 ka, to its lowest value for the past 15 kyr, before gradually increasing to the present. Between 14.8 ka and 8.6 ka, its accumulation rate exhibited strong maxima at 14.4, 13.0, and 9.9 ka. The oldest maximum corresponds to melt-water pulse IA into the Gulf of Mexico. A relative minimum, centered at about 11.1 ka, corresponds to melt-water pulse IB; a strong maximum occurs in the immediately overlying sediment. The maximum at 13.0 ka corresponds to onset of the Younger Dryas cold event. This pattern to the accumulation rate of Mo (and V) can be interpreted in terms of its deposition from bottom water of the basin, the hydrogenous fraction, under SO42- -reducing conditions, during times of intense bottom-water advection 14.8 ka to 11.1 ka and significantly less intense bottom-water advection 11 ka to the present. The accumulation rate of Cd shows a pattern that is only slightly different from that of Mo, although its deposition was determined largely by the rain rate of organic matter into the bottom water, a biogenic fraction whose deposition was driven by upwelling of nutrient-enriched water into the photic zone. Its accumulation exhibits only moderately high rates, on average, during both melt-water pulses. Its highest rate, and that of upwelling, occurred during the Younger Dryas, and again following melt-water pulse IB. The marine fractions of Cu, Ni, and Zn also have a strong biogenic signal. The siliciclastic terrigenous debris, however, represents the dominant source, and host, of Cu, Ni, and Zn. All four trace elements have a consid-erably weaker hydrogenous signal than biogenic signal. Accumulation rates of the terrigenous fraction, as reflected by accumulation rates of Th and Ga, show strong maxima at 16.2 and 12.7 ka and minima at 14.1 and 11.1 ka. Co, Li, REE, and Y have a similar distribution. The minima occurred during melt-water pulses IA and IB, the maxima during the Younger Dryas and the rise in sea level following the last glacial maximum.

30 CFR 56.19062 - Maximum acceleration and deceleration.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Maximum acceleration and deceleration. 56.19062 Section 56.19062 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Hoisting Hoisting Procedures § 56.19062 Maximum acceleration and deceleration. Maximum normal operating...

30 CFR 57.19062 - Maximum acceleration and deceleration.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Maximum acceleration and deceleration. 57.19062 Section 57.19062 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Hoisting Hoisting Procedures § 57.19062 Maximum acceleration and deceleration. Maximum normal operating...

Co-disposal of electronic waste with municipal solid waste in bioreactor landfills.

PubMed

Visvanathan, C; Visvanthan, C; Yin, Nang Htay; Karthikeyan, Obuli P

2010-12-01

Three pilot scale lysimeters were adopted to evaluate the stability pattern and leaching potential of heavy metals from MSW landfills under the E-waste co-disposed condition. One lysimeter served as control and solely filled with MSW, whereas the other two lysimeters were provided with 10% and 25% of E-waste scraps (% by weight), respectively. The reactors were monitored over a period of 280 days at ambient settings with continuous leachate recirculation. Stabilization pattern of carbon appears to be more than 50% in all the three lysimeters with irrespective of their operating conditions. Iron and zinc concentrations were high in leachate during bioreactor landfill operation and correlating with the TCLP leachability test results. In contrast, Pb concentration was around <0.6 mg/L, but which showed maximum leaching potential under TCLP test conditions. But, no heavy metal accumulation was found with leachate recirculation practices in lysimeters. Mobility of the metal content from the E-waste was found to be amplified with the long term disposal or stabilization within landfills. The results showed that the TCLP test cannot be completely reliable tool for measuring long-term leachability of toxic substances under landfill condition; rather landfill lysimeter studies are necessary to get the real scenario. Copyright © 2010 Elsevier Ltd. All rights reserved.

Study of a combined heterotrophic and sulfur autotrophic denitrification technology for removal of nitrate in water.

PubMed

Liu, Huijuan; Jiang, Wei; Wan, Dongjin; Qu, Jiuhui

2009-09-30

A combined two-step process of heterotrophic denitrification in a fluidized reactor and sulfur autotrophic denitrification processes (CHSAD) was developed for the removal of nitrate in drinking water. In this process, the advantage of high efficiency of heterotrophic denitrification with non-excessive methanol and the advantage of non-pollution of sulfur autotriphic denitrification were integrated in this CHSAD process. And, this CHSAD process had the capacity of pH balance and could control the concentration of SO(4)(2-) in effluent by adjusting the operation condition. When the influent nitrate was 30 mg NO(3)(-)-N/L, the reactor could be operated efficiently at the hydraulic retention time (HRT) ranging from 20 to 40 min with C:N ratio (mg CH(3)OH:mg NO(3)(-)-N) of 2.0 (methanol as carbon source). The nitrate removal was nearly 100% and there was no accumulated nitrite or residual methanol in the effluent. The effluent pH was about 7.5 and the sulfate concentration was lower than 130 mg/L. The maximum volume-loading rate of the reactor was 2.16 kg NO(3)(-)-N/(m(3)d). The biomass and scanning electron microscopy graphs of biofilm were also analyzed.

Pilot-scale benthic microbial electrochemical system (BMES) for the bioremediation of polluted river sediment

NASA Astrophysics Data System (ADS)

Li, Henan; He, Weihua; Qu, Youpeng; Li, Chao; Tian, Yan; Feng, Yujie

2017-07-01

A benthic microbial electrochemical system (BMES) of 350 L is built for the bioremediation of river sediment (Ashi river, Harbin, China). Carbon mesh anode with honeycomb-structure supports and activated carbon cathodes are applied for the construction. Synthesis wastewater with glucose is added to simulate the natural condition of Ashi River as an intermittent pollutant-holding water body and accelerate the removal of accumulated bio-refractory organic contents in sediment, represented by the concentration changes of polycyclic aromatic hydrocarbons, as the co-metabolic substrate for bacteria. The effluent TOC in the water layer of BMES is stable at 40 ± 2 mg L-1 and further reduced to 19 ± 5 mg L-1 after the addition of synthesis wastewater, while the removal of polycyclic aromatic hydrocarbons(Benzo(b)fluoranthene, Benzo(k)fluoranthene and Benzo(a)pyrene) in sediment samples reaches 74%. A maximum power density of 63 ± 3 mW m-2 is achieved by BMES, which decrease to 42 ± 2 mW m-2 due to cathode degradation and further reduce to 30 ± 3 mW m-2 attributed to substrate limitation at the end of operation. Community analyses show the diversity of anode community is improved during operation and the abundance of Chloroflexi, Firmicutes and exoelectrogenic microbes like G. psychrophilus increase.

Temporal and spatial variations on accumulation of nomilin and limonin in the pummelos.

PubMed

Wang, Fusheng; Yu, Xiaohan; Liu, Xiaona; Shen, Wanxia; Zhu, Shiping; Zhao, Xiaochun

2016-09-01

Limonoids are the important secondary metabolites in the citrus. In this study, the accumulation of limonoids at different fruit developmental stages and distribution among different genotypes, tissues and developmental stages were investigated in 12 pummelo varieties. The large variations on limonoids concentration were found among different varieties, which ranged from 233.78 mg/kg FW to 4090.41 mg/kg FW in the seeds at full color stage of the fruit. Classification of pummelos based on the limonoids content divided 12 varieties into three groups. It was matched well with the geographic origination of the pummelo varieties, suggesting that the accumulation of limonoids was mainly determined by the genotype of the pummelo. Accumulation of the limonoids in different tissues was highly variable, and in a tissue specific fashion. The trend of the change on the levels of nomilin and limonin in the seeds and segment membrane were corresponded to the physiological development of the fruit. The rapid accumulation of nomilin and limonoids was observed from the physiological ripening of the seeds. It suggested that physiological maturation of the seeds is a key point that the seeds accelerate the accumulation of nomilin and limonin. In most of pummelo varieties, 10% color break of the fruit was a phenotypic landmark associated with the maximum level of nomilin accumulated in the seeds. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Chilling and heat requirements for flowering in temperate fruit trees

NASA Astrophysics Data System (ADS)

Guo, Liang; Dai, Junhu; Ranjitkar, Sailesh; Yu, Haiying; Xu, Jianchu; Luedeling, Eike

2014-08-01

Climate change has affected the rates of chilling and heat accumulation, which are vital for flowering and production, in temperate fruit trees, but few studies have been conducted in the cold-winter climates of East Asia. To evaluate tree responses to variation in chill and heat accumulation rates, partial least squares regression was used to correlate first flowering dates of chestnut ( Castanea mollissima Blume) and jujube ( Zizyphus jujube Mill.) in Beijing, China, with daily chill and heat accumulation between 1963 and 2008. The Dynamic Model and the Growing Degree Hour Model were used to convert daily records of minimum and maximum temperature into horticulturally meaningful metrics. Regression analyses identified the chilling and forcing periods for chestnut and jujube. The forcing periods started when half the chilling requirements were fulfilled. Over the past 50 years, heat accumulation during tree dormancy increased significantly, while chill accumulation remained relatively stable for both species. Heat accumulation was the main driver of bloom timing, with effects of variation in chill accumulation negligible in Beijing's cold-winter climate. It does not seem likely that reductions in chill will have a major effect on the studied species in Beijing in the near future. Such problems are much more likely for trees grown in locations that are substantially warmer than their native habitats, such as temperate species in the subtropics and tropics.

Chilling and heat requirements for flowering in temperate fruit trees.

PubMed

Guo, Liang; Dai, Junhu; Ranjitkar, Sailesh; Yu, Haiying; Xu, Jianchu; Luedeling, Eike

2014-08-01

Climate change has affected the rates of chilling and heat accumulation, which are vital for flowering and production, in temperate fruit trees, but few studies have been conducted in the cold-winter climates of East Asia. To evaluate tree responses to variation in chill and heat accumulation rates, partial least squares regression was used to correlate first flowering dates of chestnut (Castanea mollissima Blume) and jujube (Zizyphus jujube Mill.) in Beijing, China, with daily chill and heat accumulation between 1963 and 2008. The Dynamic Model and the Growing Degree Hour Model were used to convert daily records of minimum and maximum temperature into horticulturally meaningful metrics. Regression analyses identified the chilling and forcing periods for chestnut and jujube. The forcing periods started when half the chilling requirements were fulfilled. Over the past 50 years, heat accumulation during tree dormancy increased significantly, while chill accumulation remained relatively stable for both species. Heat accumulation was the main driver of bloom timing, with effects of variation in chill accumulation negligible in Beijing’s cold-winter climate. It does not seem likely that reductions in chill will have a major effect on the studied species in Beijing in the near future. Such problems are much more likely for trees grown in locations that are substantially warmer than their native habitats, such as temperate species in the subtropics and tropics.

[Response of indica rice spikelet differentiation and degeneration to air temperature and solar radiation of different sowing dates].

PubMed

Wang, Ya Liang; Zhang, Yu Ping; Xiang, Jing; Wang, Lei; Chen, Hui Zhe; Zhang, Yi Kai; Zhang, Wen Qian; Zhu, De Feng

2017-11-01

In this study, three rice varieties, including three-line hybrid indica rice Wuyou308 and Tianyouhuazhan, and inbred indica rice Huanghuazhan were used to investigate the effects of air temperature and solar radiation on rice growth duration and spikelet differentiation and degeneration. Ten sowing-date treatments were conducted in this field experiment. The results showed that the growth duration of three indica rice varieties were more sensitive to air temperature than to day-length. With average temperature increase of 1 ℃, panicle initiation advanced 1.5 days, but the panicle growth duration had no significant correlation with the temperature and day-length. The number of spikelets and differentiated spikelets revealed significant differences among different sowing dates. Increases in average temperature, maximum temperature, minimum temperature, effective accumulated temperature, temperature gap and the solar radiation benefited dry matter accumulation and spikelet differentiation of all varieties. With increases of effective accumulated temperature, diurnal temperature gap and solar radiation by 50 ℃, 1 ℃, 50 MJ·m -2 during panicle initiation stage, the number of differentiated spikelets increased 10.5, 14.3, 17.1 respectively. The rate of degenerated spikelets had a quadratic correlation with air temperature, extreme high and low temperature aggravated spikelets degeneration, and low temperature stress made worse effect than high temperature stress. The rate of spikelet degeneration dramatically rose with the temperature falling below the critical temperature, the critical effective accumulated temperature, daily average temperature, daily maximum temperature and minimum temperature during panicle initiation were 550-600 ℃, 24.0-26.0 ℃, 32.0-34.0 ℃, 21.0-23.0 ℃, respectively. In practice, the natural condition of appropriate high temperature, large diurnal temperature gap and strong solar radiation were conducive to spikelet differentiation, and hindered the spikelet degeneration.

[Effect of different aeration ways on migration and transformation of nitrogen in heavily polluted urban river].

PubMed

Liu, Bo; Wang, Guo-Xiang; Wang, Feng-He; Du, Xu; Ling, Fen; Xia, Jin

2011-10-01

Water and sediment samples were collected from a heavily polluted urban river in the Xianlin University Town of Nanjing. We examined the effects of different aeration ways (aerating to sediments, aerating to water) on migration and transformation of nitrogen, using the indoor experimental method. The results showed that: nitrogen release from sediments in the form of NH4(+) -N that will accumulate under anaerobic conditions with increasing temperature; the maximum accumulation of NH4(+) -N in overlying water showed that aerating to water group < aerating to sediment group < control group and the maximum concentrations reached 9.40 mg x L(-1), 11.24 mg x L(-1) and 19.30 mg x L(-1), respectively; nitrogen compounds were generally eliminated from experiment system by a process of ammonia volatilization and a combination of two processes, i. e. nitrification and denitrification under aerating conditions; aerating to sediment was more effective for nitrogen removal than aerating to water, which was removed from overlying water, pore water and sediment; at the experimental endpoint, the concentrations of NH4(+) -N in pore water and sediment were significantly decreased by 64.36% and 58.73% respectively compared with those before aeration in aerating to sediment group and that were decreased by 39.53% and 38.78% respectively in aerating to water group; during nitrogen transformation process in overlying water, start-up of nitrification was slowly under aerating conditions; it took 9 days to realize nitrification under aerating to water conditions and 16 days under sediment aeration conditions; the NO2(-) -N accumulation took place in overlying water under the condition of aeration; the sustain time of NO2(-) -N accumulating was 17 days in aerating to water group and that was 14 days in aerating to sediment group.

The effects of moderately high temperature on zeaxanthin accumulation and decay.

PubMed

Zhang, Ru; Kramer, David M; Cruz, Jeffrey A; Struck, Kimberly R; Sharkey, Thomas D

2011-09-01

Moderately high temperature reduces photosynthetic capacities of leaves with large effects on thylakoid reactions of photosynthesis, including xanthophyll conversion in the lipid phase of the thylakoid membrane. In previous studies, we have found that leaf temperature of 40°C increased zeaxanthin accumulation in dark-adapted, intact tobacco leaves following a brief illumination, but did not change the amount of zeaxanthin in light-adatped leaves. To investigate heat effects on zeaxanthin accumulation and decay, zeaxanthin level was monitored optically in dark-adapted, intact tobacco and Arabidopsis thaliana leaves at either 23 or 40°C under 45-min illumination. Heated leaves had more zeaxanthin following 3-min light but had less or comparable amounts of zeaxanthin by the end of 45 min of illumination. Zeaxanthin accumulated faster at light initiation and decayed faster upon darkening in leaves at 40°C than leaves at 23°C, indicating that heat increased the activities of both violaxanthin de-epoxidase (VDE) and zeaxanthin epoxidase (ZE). In addition, our optical measurement demonstrated in vivo that weak light enhances zeaxanthin decay relative to darkness in intact leaves of tobacco and Arabidopsis, confirming previous observations in isolated spinach chloroplasts. However, the maximum rate of decay is similar for weak light and darkness, and we used the maximum rate of decay following darkness as a measure of the rate of ZE during steady-state light. A simulation indicated that high temperature should cause a large shift in the pH dependence of the amount of zeaxanthin in leaves because of differential effects on VDE and ZE. This allows for the reduction in ΔpH caused by heat to be offset by increased VDE activity relative to ZE.

Measurement of snow interception and canopy effects on snow accumulation and melt in a mountainous maritime climate, Oregon, United States

NASA Astrophysics Data System (ADS)

Storck, Pascal; Lettenmaier, Dennis P.; Bolton, Susan M.

2002-11-01

The results of a 3 year field study to observe the processes controlling snow interception by forest canopies and under canopy snow accumulation and ablation in mountain maritime climates are reported. The field study was further intended to provide data to develop and test models of forest canopy effects on beneath-canopy snowpack accumulation and melt and the plot and stand scales. Weighing lysimeters, cut-tree experiments, and manual snow surveys were deployed at a site in the Umpqua National Forest, Oregon (elevation 1200 m). A unique design for a weighing lysimeter was employed that allowed continuous measurements of snowpack evolution beneath a forest canopy to be taken at a scale unaffected by variability in canopy throughfall. Continuous observations of snowpack evolution in large clearings were made coincidentally with the canopy measurements. Large differences in snow accumulation and ablation were observed at sites beneath the forest canopy and in large clearings. These differences were not well described by simple relationships between the sites. Over the study period, approximately 60% of snowfall was intercepted by the canopy (up to a maximum of about 40 mm water equivalent). Instantaneous sublimation rates exceeded 0.5 mm per hour for short periods. However, apparent average sublimation from the intercepted snow was less than 1 mm per day and totaled approximately 100 mm per winter season. Approximately 72 and 28% of the remaining intercepted snow was removed as meltwater drip and large snow masses, respectively. Observed differences in snow interception rate and maximum snow interception capacity between Douglas fir (Pseudotsuga menziesii), white fir (Abies concolor), ponderosa pine (Pinus ponderosa), and lodgepole pine (Pinus contorta) were minimal.

40 CFR 57.203 - Contents of the application.

Code of Federal Regulations, 2010 CFR

2010-07-01

... emission of sulfur dioxide; the characteristics of all gas streams emitted from the smelter's process...'s maximum daily production capacity (as defined in § 57.103(r)), the operational rate (in pounds of... smelter is operating at that capacity; and the smelter's average and maximum daily production rate for...

Regulation of Viable and Optimal Cohorts

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

Aubin, Jean-Pierre, E-mail: aubin.jp@gmail.com

This study deals with the evolution of (scalar) attributes (resources or income in evolutionary demography or economics, position in traffic management, etc.) of a population of “mobiles” (economic agents, vehicles, etc.). The set of mobiles sharing the same attributes is regarded as an instantaneous cohort described by the number of its elements. The union of instantaneous cohorts during a mobile window between two attributes is a cohort. Given a measure defining the number of instantaneous cohorts, the accumulation of the mobile attributes on a evolving mobile window is the measure of the cohort on this temporal mobile window. Imposing accumulationmore » constraints and departure conditions, this study is devoted to the regulation of the evolutions of the attributes which are1.viable in the sense that the accumulations constraints are satisfied at each instant;2.and, among them, optimal, in the sense that both the duration of the temporal mobile window is maximum and that the accumulation on this temporal mobile window is the largest viable one. This value is the “accumulation valuation” function. Viable and optimal evolutions under accumulation constraints are regulated by an “implicit Volterra integro-differential inclusion” built from the accumulation valuation function, solution to an Hamilton–Jacobi–Bellman partial differential equation under constraints which is constructed for this purpose.« less

Simulation of Biomass Accumulation Pattern in Vapor-Phase Biofilters

PubMed Central

Xi, Jin-Ying; Hu, Hong-Ying; Zhang, Xian

2012-01-01

Abstract Existence of inert biomass and its impact on biomass accumulation patterns and biofilter performance were investigated. Four biofilters were set up in parallel to treat gaseous toluene. Each biofilter operated under different inlet toluene loadings for 100 days. Two microbial growth models, one with an inert biomass assumption and the other without, were established and compared. Results from the model with the inert biomass assumption showed better agreement with the experimental data than those based on the model without the inert biomass assumption thus verifying that inert biomass accumulation cannot be ignored in the long-term operation of biofilters. According to the model with an inert biomass assumption, the ratio of active biomass to total biomass will decrease and the inert biomass will become dominant in total biomass after a period of time. Filter bed structure simulation results showed that the void fraction is more sensitive to biomass accumulation than the specific surface area. The final void fraction of the biofilters with the highest inlet toluene loading is only 67% of its initial level while the final specific surface area is 82%. Identification and quantification of inert biomass will give a better understanding of biomass accumulation in biofilters and will result in a more exact simulation of biomass change during long-term operations. Results also indicate that an ideal biomass control technique should be able to remove most inert biomass while simultaneously preserving as much active biomass as possible. PMID:22693411

Spark-Timing Control Based on Correlation of Maximum-Economy Spark Timing, Flame-front Travel, and Cylinder-Pressure Rise

NASA Technical Reports Server (NTRS)

Cook, Harvey A; Heinicke, Orville H; Haynie, William H

1947-01-01

An investigation was conducted on a full-scale air-cooled cylinder in order to establish an effective means of maintaining maximum-economy spark timing with varying engine operating conditions. Variable fuel-air-ratio runs were conducted in which relations were determined between the spark travel, and cylinder-pressure rise. An instrument for controlling spark timing was developed that automatically maintained maximum-economy spark timing with varying engine operating conditions. The instrument also indicated the occurrence of preignition.

Heat Generation in Axial and Centrifugal Flow Left Ventricular Assist Devices.

PubMed

Yost, Gardner; Joseph, Christine Rachel; Royston, Thomas; Tatooles, Antone; Bhat, Geetha

Despite increasing use of left ventricular assist devices (LVADs) as a surgical treatment for advanced heart failure in an era of improved outcomes with LVAD support, the mechanical interactions between these pumps and the cardiovascular system are not completely understood. We utilized an in vitro mock circulatory loop to analyze the heat production incurred by operation of an axial flow and centrifugal flow LVAD. A HeartMate II and a HeartWare HVAD were connected to an abbreviated flow loop and were implanted in a viscoelastic gel. Temperature was measured at the surface of each LVAD. Device speed and fluid viscosity were altered and, in the HeartMate II, as artificial thrombi were attached to the inflow stator, impeller, and outflow stator. The surface temperatures of both LVADs increased in all trials and reached a plateau within 80 minutes of flow initiation. Rate of heat generation and maximum system temperature were greater when speed was increased, when viscosity was increased, and when artificial thrombi were attached to the HeartMate II impeller. Normal operation of these two widely utilized LVADs results in appreciable heat generation in vitro. Increased pump loading resulted in more rapid heat generation, which was particularly severe when a large thrombus was attached to the impeller of the HeartMate II. While heat accumulation in vivo is likely minimized by greater dissipation in the blood and soft tissues, focal temperature gains with the pump housing of these two devices during long-term operation may have negative hematological consequences.

Effect of salt-tolerant plant growth-promoting rhizobacteria on wheat plants and soil health in a saline environment.

PubMed

Upadhyay, S K; Singh, D P

2015-01-01

Salt-tolerant plant growth-promoting rhizobacteria (ST-PGPR) significantly influence the growth and yield of wheat crops in saline soil. Wheat growth improved in pots with inoculation of all nine ST-PGPR (ECe = 4.3 dS·m(-1) ; greenhouse experiment), while maximum growth and dry biomass was observed in isolate SU18 Arthrobacter sp.; simultaneously, all ST-PGPR improved soil health in treated pot soil over controls. In the field experiment, maximum wheat root dry weight and shoot biomass was observed after inoculation with SU44 B. aquimaris, and SU8 B. aquimaris, respectively, after 60 and 90 days. Isolate SU8 B. aquimaris, induced significantly higher proline and total soluble sugar accumulation in wheat, while isolate SU44 B. aquimaris, resulted in higher accumulation of reducing sugars after 60 days. Percentage nitrogen (N), potassium (K) and phosphorus (P) in leaves of wheat increased significantly after inoculation with ST-PGPR, as compared to un-inoculated plants. Isolate SU47 B. subtilis showed maximum reduction of sodium (Na) content in wheat leaves of about 23% at both 60 and 90 days after sowing, and produced the best yield of around 17.8% more than the control. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.

Analysis of arsenic and antimony distribution within plants growing at an old mine site in Ouche (Cantal, France) and identification of species suitable for site revegetation.

PubMed

Jana, Ulrike; Chassany, Vincent; Bertrand, Georges; Castrec-Rouelle, Maryse; Aubry, Emmanuel; Boudsocq, Simon; Laffray, Daniel; Repellin, Anne

2012-11-15

One of the objectives of this study was to assess the contamination levels in the tailings of an old antimony mine site located in Ouche (Cantal, France). Throughout the 1.3 ha site, homogenous concentrations of antimony and arsenic, a by-product of the operation, were found along 0-0.5 m-deep profiles. Maximum concentrations for antimony and arsenic were 5780 mg kg(-1) dry tailings and 852 mg kg(-1) dry tailings, respectively. Despite the presence of the contaminants and the low pH and organic matter contents of the tailings, several patches of vegetation were found. Botanical identification determined 12 different genera/species. The largest and most abundant plants were adult pines (Pinus sylvestris), birches (Betula pendula) and the bulrush (Juncus effusus). The distribution of the metalloids within specimens of each genera/species was analysed in order to deduce their concentration and translocation capacities. This was the second goal of this work. All plant specimens were highly contaminated with both metalloids. Most were root accumulators with root to shoot translocation factors <1. Whereas contamination levels were high overall, species with both a low translocation factor and a low root accumulation coefficient were identified as suitable candidates for the complete revegetation of the site. Species combining those characteristics were the perennials P. sylvestris, B. pendula, Cytisus scoparius and the herbaceous Plantago major, and Deschampsia flexuosa. Copyright © 2012 Elsevier Ltd. All rights reserved.

a Weather Monitoring System for Application to Apple and Corn Production

NASA Astrophysics Data System (ADS)

Stirm, Walter Leroy

Many crop management decisions are based on weather -crop development relationships. Daily weather data is currently used in most crop development research and applied models. Present weather and computer technology now makes possible monitoring of crop development on a realtime basis. This research tests a method of computing crop sensitive temperatures for corn and apple using standard hourly meteorological data. The method also makes use of detailed plant physiological stage measurements to determine timing of vital cultural operations tied to the observed weather conditions. The sensitive temperature method incorporates very short term weather variability accounting for changes in the cloud cover, radiation rates, evaporative cooling and other factors involved in the plant's energy balance. The relationship of plant and weather measurements are also used to determine corn emergence, corn grain drydown rate and fruit harvest duration. The monitoring system also incorporates a crop growth unit forecast technique employing short and medium range temperature forecasts of the National Weather Service. The projections of growth units are made for five and ten days into the future. Predicted growth unit accumulations are compared to historical growth unit accumulations to determine the forecast stage. The sensitive temperature crop monitoring system removes some of the error involved in evaluation of growth units by average daily temperature. Carry over maximum and minimums, extended duration of warm or cool periods within the day and disruption of diurnal temperature curve by passage of fronts are eliminated.

Intermittent Drug Dosing Intervals Guided by the Operational Multiple Dosing Half Lives for Predictable Plasma Accumulation and Fluctuation

PubMed Central

Grover, Anita; Benet, Leslie Z.

2013-01-01

Intermittent drug dosing intervals are usually initially guided by the terminal pharmacokinetic half life and are dependent on drug formulation. For chronic multiple dosing and for extended release dosage forms, the terminal half life often does not predict the plasma drug accumulation or fluctuation observed. We define and advance applications for the operational multiple dosing half lives for drug accumulation and fluctuation after multiple oral dosing at steady-state. Using Monte Carlo simulation, our results predict a way to maximize the operational multiple dosing half lives relative to the terminal half life by using a first-order absorption rate constant close to the terminal elimination rate constant in the design of extended release dosage forms. In this way, drugs that may be eliminated early in the development pipeline due to a relatively short half life can be formulated to be dosed at intervals three times the terminal half life, maximizing compliance, while maintaining tight plasma concentration accumulation and fluctuation ranges. We also present situations in which the operational multiple dosing half lives will be especially relevant in the determination of dosing intervals, including for drugs that follow a direct PKPD model and have a narrow therapeutic index, as the rate of concentration decrease after chronic multiple dosing (that is not the terminal half life) can be determined via simulation. These principles are illustrated with case studies on valproic acid, diazepam, and anti-hypertensives. PMID:21499748

Development of accumulated heat stress index based on time-weighted function

NASA Astrophysics Data System (ADS)

Lee, Ji-Sun; Byun, Hi-Ryong; Kim, Do-Woo

2016-05-01

Heat stress accumulates in the human body when a person is exposed to a thermal condition for a long time. Considering this fact, we have defined the accumulated heat stress (AH) and have developed the accumulated heat stress index (AHI) to quantify the strength of heat stress. AH represents the heat stress accumulated in a 72-h period calculated by the use of a time-weighted function, and the AHI is a standardized index developed by the use of an equiprobability transformation (from a fitted Weibull distribution to the standard normal distribution). To verify the advantage offered by the AHI, it was compared with four thermal indices the humidex, the heat index, the wet-bulb globe temperature, and the perceived temperature used by national governments. AH and the AHI were found to provide better detection of thermal danger and were more useful than other indices. In particular, AH and the AHI detect deaths that were caused not only by extremely hot and humid weather, but also by the persistence of moderately hot and humid weather (for example, consecutive daily maximum temperatures of 28-32 °C), which the other indices fail to detect.

Arctic Circle Traverse 2010 (ACT-10): South East Greenland snow accumulation variability from firn coring and ice sounding radar

NASA Astrophysics Data System (ADS)

Forster, R. R.; Miege, C.; Box, J. E.; McConnell, J.; Spikes, V. B.; Burgess, E. W.

2010-12-01

The Greenland Ice Sheet plays an important role in Earth’s climate system evolution. The snow accumulation rate is the largest single mass budget term. With only 14% of the ice sheet area, Southeast Greenland contains the highest accumulation rates, accounting for one third of the total snow accumulation and annual variability. The high accumulation rates have made the region less desirable for long climate record ice cores and therefore, contain relatively very few in situ measurements to constrain the ice sheet mass budget. We present annual snow accumulation rates from the Arctic Circle Traverse 2010 (ACT-10). During April and May 2010 we acquired three 50 m firn cores connected by surface-based 400 MHz ground penetrating radar (GPR) in Southeast Greenland. The traverse repeated and extended the original Arctic Circle Traverse in 2004 (Spikes et al., 2004). Dating is achieved using geochemical analysis of the cores to identify isochronal layers detected by the GPR yielding annual accumulation estimates along the traverse between the core sites. The 300 km ACT-10 GPR snowmobile traverse extended the ACT-04 path 80 km to the lowest elevation core site at 1776 m. Meanwhile, airborne radars, operating as part of NASA’s Operation IceBridge also acquired data over the full length of the ACT-10 path, simultaneously with a portion of the traverse and within days for the remaining segments. The IceBridge and ACT-10 data are to be combined in a calibration effort such that snow accumulation rates may be mapped elsewhere in Greenland and even in Antarctica.

Interhemispheric ice-sheet synchronicity during the last glacial maximum

USGS Publications Warehouse

Weber, Michael E.; Clark, Peter U.; Ricken, Werner; Mitrovica, Jerry X.; Hostetler, Steven W.; Kuhn, Gerhard

2011-01-01

The timing of the last maximum extent of the Antarctic ice sheets relative to those in the Northern Hemisphere remains poorly understood. We develop a chronology for the Weddell Sea sector of the East Antarctic Ice Sheet that, combined with ages from other Antarctic ice-sheet sectors, indicates that the advance to and retreat from their maximum extent was within dating uncertainties synchronous with most sectors of Northern Hemisphere ice sheets. Surface climate forcing of Antarctic mass balance would probably cause an opposite response, whereby a warming climate would increase accumulation but not surface melting. Our new data support teleconnections involving sea-level forcing from Northern Hemisphere ice sheets and changes in North Atlantic deep-water formation and attendant heat flux to Antarctic grounding lines to synchronize the hemispheric ice sheets.

Interhemispheric ice-sheet synchronicity during the Last Glacial Maximum.

PubMed

Weber, Michael E; Clark, Peter U; Ricken, Werner; Mitrovica, Jerry X; Hostetler, Steven W; Kuhn, Gerhard

2011-12-02

The timing of the last maximum extent of the Antarctic ice sheets relative to those in the Northern Hemisphere remains poorly understood. We develop a chronology for the Weddell Sea sector of the East Antarctic Ice Sheet that, combined with ages from other Antarctic ice-sheet sectors, indicates that the advance to and retreat from their maximum extent was within dating uncertainties synchronous with most sectors of Northern Hemisphere ice sheets. Surface climate forcing of Antarctic mass balance would probably cause an opposite response, whereby a warming climate would increase accumulation but not surface melting. Our new data support teleconnections involving sea-level forcing from Northern Hemisphere ice sheets and changes in North Atlantic deep-water formation and attendant heat flux to Antarctic grounding lines to synchronize the hemispheric ice sheets.

Concentrations and environmental fate of Ra in cation-exchange regeneration brine waste disposed to septic tanks and accumulation in sludge, New Jersey Coastal Plain, USA.

PubMed

Szabo, Zoltan; Jacobsen, Eric; Kraemer, Thomas F; Parsa, Bahman

2008-06-01

Concentrations of Ra in liquid and solid wastes generated from 15 softeners treating domestic well waters from New Jersey Coastal Plain aquifers (where combined Ra ((226)Ra plus (228)Ra) concentrations commonly exceed 0.185 Bq L(-1)) were determined. Softeners, when maintained, reduced combined Ra about 10-fold (<0.024 Bq L(-1)). Combined Ra exceeded 0.185 Bq L(-1) at 1 non-maintained system. Combined Ra was enriched in regeneration brine waste (maximum, 81.2 Bq L(-1)), but concentrations in septic-tank effluents receiving brine waste were less than in the untreated ground waters. The maximum combined Ra concentration in aquifer sands (40.7 Bq kg(-1) dry weight) was less than that in sludge from the septic tanks (range, 84-363 Bq kg(-1)), indicating Ra accumulation in sludge from effluent. The combined Ra concentration in sludge from the homeowners' septic systems falls within the range reported for sludge samples from publicly owned treatment works within the region.

Concentrations and environmental fate of Ra in cation-exchange regeneration brine waste disposed to septic tanks and accumulation in sludge, New Jersey Coastal Plain, USA

USGS Publications Warehouse

Szabo, Z.; Jacobsen, E.; Kraemer, T.F.; Parsa, B.

2008-01-01

Concentrations of Ra in liquid and solid wastes generated from 15 softeners treating domestic well waters from New Jersey Coastal Plain aquifers (where combined Ra (226Ra plus 228Ra) concentrations commonly exceed 0.185 Bq L-1) were determined. Softeners, when maintained, reduced combined Ra about 10-fold (<0.024 Bq L-1). Combined Ra exceeded 0.185 Bq L-1 at 1 non-maintained system. Combined Ra was enriched in regeneration brine waste (maximum, 81.2 Bq L-1), but concentrations in septic-tank effluents receiving brine waste were less than in the untreated ground waters. The maximum combined Ra concentration in aquifer sands (40.7 Bq kg-1 dry weight) was less than that in sludge from the septic tanks (range, 84-363 Bq kg-1), indicating Ra accumulation in sludge from effluent. The combined Ra concentration in sludge from the homeowners' septic systems falls within the range reported for sludge samples from publicly owned treatment works within the region.

Inhibitory effects of soluble algae products (SAP) released by Scenedesmus sp. LX1 on its growth and lipid production.

PubMed

Zhang, Tian-Yuan; Yu, Yin; Wu, Yin-Hu; Hu, Hong-Ying

2013-10-01

Soluble algal products (SAP) accumulated in culture medium via water reuse may affect the growth of microalga during the cultivation. Scenedesmus sp. LX1, a freshwater microalga, was used in this study to investigate the effect of SAP on growth and lipid production of microalga. Under the SAP concentrations of 6.4-25.8 mg L(-1), maximum algal density (K) and maximum growth rate (Rmax) of Scenedesmus sp. LX1 were decreased by 50-80% and 35-70% compared with the control group, respectively. The effect of SAP on lipid accumulation of Scenedesmus sp. LX1 was non-significant. According to hydrophilic-hydrophobic and acid-base properties, SAP was fractionized into six fractions. All of the fractions could inhibit the growth of Scenedesmus sp. LX1. Organic bases (HIB, HOB) and hydrophilic acids (HIA) showed the strongest inhibition. HIA could also decrease the lipid content of Scenedesmus sp. LX1 by 59.2%. As the inhibitory effect, SAP should be seriously treated before water reuse. Copyright © 2013 Elsevier Ltd. All rights reserved.

Atmospheric fallout radionuclides in peatland from Southern Poland.

PubMed

Mróz, Tomasz; Łokas, Edyta; Kocurek, Justyna; Gąsiorek, Michał

2017-09-01

Two peat profiles were collected in a peat bog located in Southern Poland and their geochronology were determined using 210 Pb, 238,239+240 Pu and 137 Cs radiometric techniques. The 210 Pb chronologies were established using the constant rate of supply model (CRS) and are in good agreement with the Pu isotopes and 137 Cs time markers. Maximum activities of Pu isotopes were found at a depth corresponding to the early 1960s, which is the period characterized by the maximum nuclear weapon tests. The results showed that the 210 Pb method is the most accurate technique for the determination age and accumulation rate of a peat. The next part of this study calculated linear accumulation rates by analyzing 238,239+240 Pu and 137 Cs vertical distributions in the profiles. Activities of fallout isotopes were also measured in plants covering the peatland. The highest activities of 137 Cs and 210 Pb were found in Calluna vulgaris samples, and 239+240 Pu were found only in two samples (C. vulgaris and leaves of Oxycoccus quadripelatus). Copyright © 2017 Elsevier Ltd. All rights reserved.

Modeling Contamination Migration on the Chandra X-ray Observatory II

NASA Technical Reports Server (NTRS)

O'Dell, Steve; Swartz, Doug; Tice, Neil; Plucinsky, Paul; Grant, Catherine; Marshall, Herman; Vikhlinin, Alexey

2013-01-01

During its first 14 years of operation, the cold (about -60degC) optical blocking filter of the Advanced CCD Imaging Spectrometer (ACIS), aboard the Chandra X-ray Observatory, has accumulated a growing layer of molecular contamination that attenuates low-energy x rays. Over the past few years, the accumulation rate, spatial distribution, and composition may have changed, perhaps partially related to changes in the operating temperature of the ACIS housing. This evolution of the accumulation of the molecular contamination has motivated further analysis of contamination migration on the Chandra X-ray Observatory, particularly within and near the ACIS cavity. To this end, the current study employs a higher-fidelity geometric model of the ACIS cavity, detailed thermal modeling based upon monitored temperature data, and an accordingly refined model of the molecular transport.

Startup and long term operation of enhanced biological phosphorus removal in continuous-flow reactor with granules.

PubMed

Li, Dong; Lv, Yufeng; Zeng, Huiping; Zhang, Jie

2016-07-01

The startup and long term operation of enhanced biological phosphorus removal (EBPR) in a continuous-flow reactor (CFR) with granules were investigated in this study. Through reducing the settling time from 9min to 3min gradually, the startup of EBPR in a CFR with granules was successfully realized in 16days. Under continuous-flow operation, the granules with good phosphorus and COD removal performance were stably operated for more than 6months. And the granules were characterized with particle size of around 960μm, loose structure and good settling ability. During the startup phase, polysaccharides (PS) was secreted excessively by microorganisms to resist the influence from the variation of operational mode. Results of relative quantitative PCR indicated that granules dominated by polyphosphate-accumulating organisms (PAOs) were easier accumulated in the CFR because more excellent settling ability was needed in the system. Copyright © 2016 Elsevier Ltd. All rights reserved.

Damage Accumulation in Cyclically-Loaded Glass-Ceramic Matrix Composites Monitored by Acoustic Emission

PubMed Central

Aggelis, D. G.; Dassios, K. G.; Kordatos, E. Z.; Matikas, T. E.

2013-01-01

Barium osumilite (BMAS) ceramic matrix composites reinforced with SiC-Tyranno fibers are tested in a cyclic loading protocol. Broadband acoustic emission (AE) sensors are used for monitoring the occurrence of different possible damage mechanisms. Improved use of AE indices is proposed by excluding low-severity signals based on waveform parameters, rather than only threshold criteria. The application of such improvements enhances the accuracy of the indices as accumulated damage descriptors. RA-value, duration, and signal energy follow the extension cycles indicating moments of maximum or minimum strain, while the frequency content of the AE signals proves very sensitive to the pull-out mechanism. PMID:24381524

Studies on sustainability of simulated constructed wetland system for treatment of urban waste: Design and operation.

PubMed

Upadhyay, A K; Bankoti, N S; Rai, U N

2016-03-15

New system configurations and wide range of treatability make constructed wetland (CW) as an eco-sustainable on-site approach of waste management. Keeping this view into consideration, a novel configured three-stage simulated CW was designed to study its performance efficiency and relative importance of plants and substrate in purification processes. Two species of submerged plant i.e., Potamogeton crispus and Hydrilla verticillata were selected for this study. After 6 months of establishment, operation and maintenance of simulated wetland, enhanced reduction in physicochemical parameters was observed, which was maximum in the planted CW. The percentage removal (%) of the pollutants in three-stage mesocosms was; conductivity (60.42%), TDS (67.27%), TSS (86.10%), BOD (87.81%), NO3-N (81.28%) and PO4-P (83.54%) at 72 h of retention time. Submerged macrophyte used in simulated wetlands showed a significant time dependent accumulation of toxic metals (p ≤ 0.05). P. crispus accumulated the highest Mn (86.36 μg g(-1) dw) in its tissue followed by Cr (54.16 μg g(-1) dw), Pb (31.56 μg g(-1) dw), Zn (28.06 μg g(-1) dw) and Cu (25.76 μg g(-1) dw), respectively. In the case of H. verticillata, it was Zn (45.29), Mn (42.64), Pb (22.62), Cu (18.09) and Cr (16.31 μg g(-1) dw). Thus, results suggest that the application of simulated CW tackles the water pollution problem more efficiently and could be exploited in small community level as alternative and cost effective tools of phytoremediation. Copyright © 2016 Elsevier Ltd. All rights reserved.

BioChroma – A New and Patented Technology for Processing Radioactive Wastewater from Nuclear Medicine Therapy Facilities in Hospitals and Clinics

PubMed Central

Rodríguez, José Canga

2012-01-01

After undergoing radionuclide therapy, patients generate wastewater with a considerable amount of radioactivity, which can reach levels of as much as 90% of the administered dose. Due to the risk of accumulation after discharge into the sewer, it is advisable to collect this effluent for its treatment prior to final discharge. Delay and decay (natural decomposition of the isotope) is the most commonly used technical method of abating radioactive iodine, but it is frequently criticized as being complex and very expensive. BioChroma is a technology that has been developed as an alternative to these complicated and expensive systems. This paper describes this new technology and presents, as an example, a system that was installed and successfully commissioned in the middle of 2008 in a nuclear medicine ward with 12 beds in Stuttgart (Germany). Based on existing legislation, the responsible authorities and the company that operated the hospital agreed on a maximum activity level of 5 Bq/l. If a typical delay and decay system would have been installed, the 180 m3 treatment plant that was already available in the hospital cellar would have to be extended by additional 150 m3. By implementing the patented BioChroma process, the space requirements were reduced by 75%. For instance, since the new system was integrated into the existing installation, tanks accounting for 120 m³ could be used as buffering volume in the new wastewater treatment plant. The operation of the referred plant is currently producing very good results with values below the specified limit of 5 Bq/l for the isotope 131I. In addition, 90Y has been reported to be eliminated at the same time. Over the past 2 years of operation, the wastewater treatment plant has been able to achieve a maximum processing capacity of more than 2,000 l/day, which equates to a nuclear medicine ward with approx. 20 beds. The highest level recorded during the test period (of 180 days after start-up) was a peak of nearly 2,800 l/day. PMID:22942776

Growth of the eye lens: II. Allometric studies

PubMed Central

2014-01-01

Purpose The purpose of this study was to examine the ontogeny and phylogeny of lens growth in a variety of species using allometry. Methods Data on the accumulation of wet and/or dry lens weight as a function of bodyweight were obtained for 40 species and subjected to allometric analysis to examine ontogenic growth and compaction. Allometric analysis was also used to compare the maximum adult lens weights for 147 species with the maximum adult bodyweight and to compare lens volumes calculated from wet and dry weights with eye volumes calculated from axial length. Results Linear allometric relationships were obtained for the comparison of ontogenic lens and bodyweight accumulation. The body mass exponent (BME) decreased with increasing animal size from around 1.0 in small rodents to 0.4 in large ungulates for both wet and dry weights. Compaction constants for the ontogenic growth ranged from 1.00 in birds and reptiles up to 1.30 in mammals. Allometric comparison of maximum lens wet and dry weights with maximum bodyweights also yielded linear plots with a BME of 0.504 for all warm blooded species except primates which had a BME of 0.25. When lens volumes were compared with eye volumes, all species yielded a scaling constant of 0.75 but the proportionality constants for primates and birds were lower. Conclusions Ontogenic lens growth is fastest, relative to body growth, in small animals and slowest in large animals. Fiber cell compaction takes place throughout life in most species, but not in birds and reptiles. Maximum adult lens size scales with eye size with the same exponent in all species, but birds and primates have smaller lenses relative to eye size than other species. Optical properties of the lens are generated through the combination of variations in the rate of growth, rate of compaction, shape and size. PMID:24715759

Specific inspiratory muscle warm-up enhances badminton footwork performance.

PubMed

Lin, Hua; Tong, Tom Kwokkeung; Huang, Chuanye; Nie, Jinlei; Lu, Kui; Quach, Binh

2007-12-01

The effects of inspiratory muscle (IM) warm-up on IM function and on the maximum distance covered in a subsequent incremental badminton-footwork test (FWmax) were examined. Ten male badminton players were recruited to perform identical tests in three different trials in a random order. The control trial did not involve an IM warm-up, whereas the placebo and experimental trials did involve an IM warm-up consisting of two sets of 30-breath manoeuvres with an inspiratory pressure-threshold load equivalent to 15% (PLA) and 40% (IMW) maximum inspiratory mouth pressure, respectively. In the IMW trial, IM function was improved with 7.8%+/-4.0% and 6.9%+/-3.5% increases from control found in maximal inspiratory pressure at zero flow (P0) and maximal rate of P0 development (MRPD), respectively (p<0.05). FWmax was enhanced 6.8%+/-3.7%, whereas the slope of the linear relationship of the increase in the rating of perceived breathlessness for every minute (RPB/min) was reduced (p<0.05). Reduction in blood lactate ([La-]b) accumulation was observed when the test duration was identical to that of the control trial (P<0.05). In the PLA trial, no parameter was changed from control. For the changes (Delta) in parameters in IMW (n=10), negative correlations were found between DeltaP0 and DeltaRPB/min (r2=0.58), DeltaMRPD and DeltaRPB/min (r2=0.48), DeltaRPB/min, and DeltaFWmax (r2=0.55), but not between Delta[La-]b accumulation and DeltaFWmax. Such findings suggest that the IM-specific warm-up improved footwork performance in the subsequent maximum incremental badminton-footwork test. The improved footwork was partly attributable to the reduced breathless sensation resulting from the enhanced IM function, whereas the contribution of the concomitant reduction in [La-]b accumulation was relatively minor.

Design Analysis of the Ares 1 Pogo Accumulator

NASA Technical Reports Server (NTRS)

Swanson, Luke A.; Giel, Thomas V.

2009-01-01

Several accumulator designs and gas charge systems are considered in order to suppress POGO within the Ares I vehicle Upper Stage Liquid Ox ygen System. The thermodynamic and flow analysis completed to evaluat e candidate designs are presented and the results are used to evaluat e the ability of each concept to meet the levied suppression requirements. One annular accumulator design meets all suppression requirement s while also providing manufacturability and operability advantages. Of the two proposed charge systems to provide and maintain gas within the accumulator, a passive level control design meets the charge req uirements and maximizes reliability.

On Orbit ISS Oxygen Generation System Operation Status

NASA Technical Reports Server (NTRS)

Diderich, Greg S.; Polis, Pete; VanKeuren, Steven P.; Erickson, Robert; Mason, Richard

2011-01-01

The International Space Station (ISS) United States Orbital Segment (USOS) Oxygen Generation System (OGS) has accumulated almost a year of operation at varied oxygen production rates within the US Laboratory Module (LAB) since it was first activated in July 2007. It was operated intermittently through 2009 and 2010, due to filter clogging and acid accumulation in the recirculation loop. Since the installation of a deionizing bed in the recirculation loop in May of 2011 the OGA has been operated continuously. Filters in the recirculation loop have clogged and have been replaced. Hydrogen sensors have drifted apart, and a power failure may have condensed water on a hydrogen sensor. A pump delta pressure sensor failed, and a replacement new spare pump failed to start. Finally, the voltage across the cell stack increased out of tolerance due to cation contamination, and the cell stack was replaced. This paper will discuss the operating experience and characteristics of the OGS, as well as operational issues and their resolution.

Optimization of free ammonia concentration for nitrite accumulation in shortcut biological nitrogen removal process.

PubMed

Chung, Jinwook; Shim, Hojae; Park, Seong-Jun; Kim, Seung-Jin; Bae, Wookeun

2006-03-01

A shortcut biological nitrogen removal (SBNR) utilizes the concept of a direct conversion of ammonium to nitrite and then to nitrogen gas. A successful SBNR requires accumulation of nitrite in the system and inhibition of the activity of nitrite oxidizers. A high concentration of free ammonia (FA) inhibits nitrite oxidizers, but unfortunately decreases the ammonium removal rate as well. Therefore, the optimal range of FA concentration is necessary not only to stabilize nitrite accumulation but also to achieve maximum ammonium removal. In order to derive such optimal FA concentrations, the specific substrate utilization rates of ammonium and nitrite oxidizers were measured. The optimal FA concentration range appeared to be 5-10 mg/L for the adapted sludge. The simulated results from the modified inhibition model expressed by FA and ammonium/nitrite concentrations were shown very similar to the experimental results.

Immunolocalization of carbonic anhydrase and phosphoenolpyruvate carboxylase in developing seeds of Medicago sativa.

PubMed

Aivalakis, Georgios; Dimou, Maria; Flemetakis, Emmanouil; Plati, Fotini; Katinakis, Panagiotis; Drossopoulos, J B

2004-03-01

To investigate the role of carbonic anhydrase (CA; EC 4.2.1.1) and phosphoenolpyruvate carboxylase (PEPC; EC 4.1.1.31) during Medicago sativa seed development, the distribution of both proteins was examined using an immunohistological approach. Both enzymes are co-localized in most ovular and embryonic tissues. In early stages of seed development, both proteins were abundant in embryo and integuments, while at subsequent stages both proteins are accumulated in endosperm, nucellus and integuments. At late stages of seed development when both endosperm and nucellus are degraded, significant accumulation of both proteins was observed in the embryo proper. Chlorophyll was found to accumulate in embryos after the heart stage and reached a maximum at mature stage. It is suggested that CA and PEPC play a role in respiratory carbon dioxide refixation while generating malate to support amino acid and/or fatty acids biosynthesis.

Improving the nutritional value of Golden Rice through increased pro-vitamin A content.

PubMed

Paine, Jacqueline A; Shipton, Catherine A; Chaggar, Sunandha; Howells, Rhian M; Kennedy, Mike J; Vernon, Gareth; Wright, Susan Y; Hinchliffe, Edward; Adams, Jessica L; Silverstone, Aron L; Drake, Rachel

2005-04-01

"Golden Rice" is a variety of rice engineered to produce beta-carotene (pro-vitamin A) to help combat vitamin A deficiency, and it has been predicted that its contribution to alleviating vitamin A deficiency would be substantially improved through even higher beta-carotene content. We hypothesized that the daffodil gene encoding phytoene synthase (psy), one of the two genes used to develop Golden Rice, was the limiting step in beta-carotene accumulation. Through systematic testing of other plant psys, we identified a psy from maize that substantially increased carotenoid accumulation in a model plant system. We went on to develop "Golden Rice 2" introducing this psy in combination with the Erwinia uredovora carotene desaturase (crtI) used to generate the original Golden Rice. We observed an increase in total carotenoids of up to 23-fold (maximum 37 microg/g) compared to the original Golden Rice and a preferential accumulation of beta-carotene.

Volatile fatty acids produced by co-fermentation of waste activated sludge and henna plant biomass.

PubMed

Huang, Jingang; Zhou, Rongbing; Chen, Jianjun; Han, Wei; Chen, Yi; Wen, Yue; Tang, Junhong

2016-07-01

Anaerobic co-fermentation of waste activated sludge (WAS) and henna plant biomass (HPB) for the enhanced production of volatile fatty acids (VFAs) was investigated. The results indicated that VFAs was the main constituents of the released organics; the accumulation of VFAs was much higher than that of soluble carbohydrates and proteins. HPB was an advantageous substrate compared to WAS for VFAs production; and the maximum VFAs concentration in an HPB mono-fermentation system was about 2.6-fold that in a WAS mono-fermentation system. In co-fermentation systems, VFAs accumulation was positively related to the proportion of HPB in the mixed substrate, and the accumulated VFAs concentrations doubled when HPB was increased from 25% to 75%. HPB not only adjust the C/N ratio; the associated and/or released lawsone might also have a positive electron-shuttling effect on VFAs production. Copyright © 2016 Elsevier Ltd. All rights reserved.

Anthropogenic contributions to atmospheric Hg, Pb and As accumulation recorded by peat cores from southern Greenland and Denmark dated using the 14C "bomb pulse curve"

NASA Astrophysics Data System (ADS)

Shotyk, W.; Goodsite, M. E.; Roos-Barraclough, F.; Frei, R.; Heinemeier, J.; Asmund, G.; Lohse, C.; Hansen, T. S.

2003-11-01

Mercury concentrations are clearly elevated in the surface and sub-surface layers of peat cores collected from a minerotrophic ("groundwater-fed") fen in southern Greenland (GL) and an ombrotrophic ("rainwater-fed") bog in Denmark (DK). Using 14C to precisely date samples since ca. AD 1950 using the "atmospheric bomb pulse," the chronology of Hg accumulation in GL is remarkably similar to the bog in DK where Hg was supplied only by atmospheric deposition: this suggests not only that Hg has been supplied to the surface layers of the minerotrophic core (GL) primarily by atmospheric inputs, but also that the peat cores have preserved a consistent record of the changing rates of atmospheric Hg accumulation. The lowest Hg fluxes in the GL core (0.3 to 0.5 μg/m 2/yr) were found in peats dating from AD 550 to AD 975, compared to the maximum of 164 μg/m 2/yr in AD 1953. Atmospheric Hg accumulation rates have since declined, with the value for 1995 (14 μg/m 2/yr) comparable to the value for 1995 obtained by published studies of atmospheric transport modelling (12 μg/m 2/yr). The greatest rates of atmospheric Hg accumulation in the DK core are also found in the sample dating from AD 1953 and are comparable in magnitude (184 μg/m 2/yr) to the GL core; again, the fluxes have since gone into strong decline. The accumulation rates recorded by the peat core for AD 1994 (14 μg/m 2/yr) are also comparable to the value for 1995 obtained by atmospheric transport modelling (18 μg/m 2/yr). Comparing the Pb/Ti and As/Ti ratios of the DK samples with the corresponding crustal ratios (or "natural background values" for preanthropogenic peat) shows that the samples dating from 1953 also contain the maximum concentration of "excess" Pb and As. The synchroneity of the enrichments of all three elements (Hg, Pb, and As) suggests a common source, with coal-burning the most likely candidate. Independent support for this interpretation was obtained from the Pb isotope data ( 206Pb/ 207Pb = 1.1481 ± 0.0002 in the leached fraction and 1.1505 ± 0.0002 in the residual fraction) which is too radiogenic to be explained in terms of gasoline lead alone, but compares well with values for U.K. coals. In contrast, the lowest values for 206Pb/ 207Pb in the DK profile (1.1370 ± 0.0003 in the leached fraction and 1.1408 ± 0.0003 in the residual fraction) are found in the sample dating from AD 1979: this shows that the maximum contribution of leaded gasoline occurred approximately 25 yr after the zenith in total anthropogenic Pb deposition.

Impact of downward-mixing ozone on surface ozone accumulation in southern Taiwan.

PubMed

Lin, Ching-Ho

2008-04-01

The ozone that initially presents in the previous day's afternoon mixing layer can remain in the nighttime atmosphere and then be carried over to the next morning. Finally, this ozone can be brought to the ground by downward mixing as mixing depth increases during the daytime, thereby increasing surface ozone concentrations. Variation of ozone concentration during each of these periods is investigated in this work. First, ozone concentrations existing in the daily early morning atmosphere at the altitude range of the daily maximum mixing depth (residual ozone concentrations) were measured using tethered ozonesondes on 52 experimental days during 2004-2005 in southern Taiwan. Daily downward-mixing ozone concentrations were calculated by a box model coupling the measured daily residual ozone concentrations and daily mixing depth variations. The ozone concentrations upwind in the previous day's afternoon mixing layer were estimated by the combination of back air trajectory analysis and known previous day's surface ozone distributions. Additionally, the relationship between daily downward-mixing ozone concentration and daily photochemically produced ozone concentration was examined. The latter was calculated by removing the former from daily surface maximum ozone concentration. The measured daily residual ozone concentrations distributed at 12-74 parts per billion (ppb) with an average of 42 +/- 17 ppb are well correlated with the previous upwind ozone concentration (R2 = 0.54-0.65). Approximately 60% of the previous upwind ozone was estimated to be carried over to the next morning and became the observed residual ozone. The daily downward-mixing ozone contributes 48 +/- 18% of the daily surface maximum ozone concentration, indicating that the downward-mixing ozone is as important as daily photochemically produced ozone to daily surface maximum ozone accumulation. The daily downward-mixing ozone is poorly correlated with the daily photochemically produced ozone and contributes significantly to the daily variation of surface maximum ozone concentrations (R2 = 0.19). However, the contribution of downward-mixing ozone to daily ozone variation is not included in most existing statistical models developed for predicting daily ozone variation. Finally, daily surface maximum ozone concentration is positively correlated with daily afternoon mixing depth, attributable to the downward-mixing ozone.

Atmospheric Radiation Measurement program climate research facility operations quarterly report October 1 - December 31, 2008.

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

Sisterson, D. L.

2009-01-15

Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real-time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, they calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month formore » the current year and (2) site and fiscal year (FY) dating back to 1998. The US Department of Energy (DOE) requires national user facilities to report time-based operating data. The requirements concern the actual hours of operation (ACTUAL); the estimated maximum operation or uptime goal (OPSMAX), which accounts for planned downtime; and the VARIANCE [1-(ACTUAL/OPSMAX)], which accounts for unplanned downtime. The OPSMAX time for the first quarter of FY 2009 for the Southern Great Plains (SGP) site is 2,097.60 hours (0.95 x 2,208 hours this quarter). The OPSMAX for the North Slope Alaska (NSA) locale is 1,987.20 hours (0.90 x 2,208), and for the Tropical Western Pacific (TWP) locale is 1,876.80 hours (0.85 x 2,208). The OPSMAX time for the ARM Mobile Facility (AMF) is not reported this quarter because the data have not yet been released from China to the DMF for processing. The differences in OPSMAX performance reflect the complexity of local logistics and the frequency of extreme weather events. It is impractical to measure OPSMAX for each instrument or data stream. Data availability reported here refers to the average of the individual, continuous data streams that have been received by the Archive. Data not at the Archive are caused by downtime (scheduled or unplanned) of the individual instruments. Therefore, data availability is directly related to individual instrument uptime. Thus, the average percentage of data in the Archive represents the average percentage of the time (24 hours per day, 92 days for this quarter) the instruments were operating this quarter. Table 1 shows the accumulated maximum operation time (planned uptime), actual hours of operation, and variance (unplanned downtime) for the period October 1-December 31, 2008, for the fixed sites. The AMF has been deployed to China, but the data have not yet been released. The first quarter comprises a total of 2,208 hours. The average exceeded their goal this quarter.« less

Atmospheric Radiation Measurement program climate research facility operations quarterly report January 1 - March 31, 2009.

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

Sisterson, D. L.

2009-04-23

Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real-time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month formore » the current year and (2) site and fiscal year (FY) dating back to 1998. The U.S. Department of Energy (DOE) requires national user facilities to report time-based operating data. The requirements concern the actual hours of operation (ACTUAL); the estimated maximum operation or uptime goal (OPSMAX), which accounts for planned downtime; and the VARIANCE [1 - (ACTUAL/OPSMAX)], which accounts for unplanned downtime. The OPSMAX time for the second quarter of FY 2009 for the Southern Great Plains (SGP) site is 2,052.00 hours (0.95 x 2,160 hours this quarter). The OPSMAX for the North Slope Alaska (NSA) locale is 1,944.00 hours (0.90 x 2,160), and for the Tropical Western Pacific (TWP) locale is 1,836.00 hours (0.85 x 2,160). The OPSMAX time for the ARM Mobile Facility (AMF) is not reported this quarter because not all of the metadata have been acquired that are used to generate this metric. The differences in OPSMAX performance reflect the complexity of local logistics and the frequency of extreme weather events. It is impractical to measure OPSMAX for each instrument or data stream. Data availability reported here refers to the average of the individual, continuous data streams that have been received by the Archive. Data not at the Archive are caused by downtime (scheduled or unplanned) of the individual instruments. Therefore, data availability is directly related to individual instrument uptime. Thus, the average percentage of data in the Archive represents the average percentage of the time (24 hours per day, 90 days for this quarter) the instruments were operating this quarter. Summary. Table 1 shows the accumulated maximum operation time (planned uptime), actual hours of operation, and variance (unplanned downtime) for the period January 1 - March 31, 2009, for the fixed sites. The AMF has completed its mission in China but not all of the data can be released to the public at the time of this report. The second quarter comprises a total of 2,160 hours. The average exceeded our goal this quarter.« less

Heat pump having improved defrost system

DOEpatents

Chen, Fang C.; Mei, Viung C.; Murphy, Richard W.

1998-01-01

A heat pump system includes, in an operable relationship for transferring heat between an exterior atmosphere and an interior atmosphere via a fluid refrigerant: a compressor; an interior heat exchanger; an exterior heat exchanger; an accumulator; and means for heating the accumulator in order to defrost the exterior heat exchanger.

Heat pump having improved defrost system

DOEpatents

Chen, F.C.; Mei, V.C.; Murphy, R.W.

1998-12-08

A heat pump system includes, in an operable relationship for transferring heat between an exterior atmosphere and an interior atmosphere via a fluid refrigerant: a compressor; an interior heat exchanger; an exterior heat exchanger; an accumulator; and means for heating the accumulator in order to defrost the exterior heat exchanger. 2 figs.

Proline accumulation and its implication in cold tolerance of regenerable maize callus

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

Duncan, D.R.; Widholm, J.M.

1987-03-01

Embryogenic callus of maize (Zea mays L.) inbreds B37wx, H99, H99/sup 3/H95, Mo17, and Pa91 accumulated proline to levels 2.1 to 2.5 times that of control callus when subjected to mannitol-induced water stress, cool temperatures (19/sup 0/C) and abscisic acid (ABA). A combination of 0.53 molar mannitol plus 0.1 millimolar ABA induced a proline accumulation to about 4.5 times that of control callus, equivalent to approximately 0.18 millimoles proline per gram fresh weight of callus. Proline accumulation was directly related to the level of mannitol in the medium. Levels of ABA greater than 1.0 micromolar were required in the mediummore » to induce proline accumulation comparable to that induced by mannitol. Mannitol and ABA levels that induced maximum accumulation of proline also inhibited callus growth and increased tolerance to cold. Proline (12 millimolar) added to culture media also increased the tolerance of callus to 4/sup 0/C. The increased cold tolerance induced by the combination of mannitol and ABA has permitted the storage of the maize inbreds A632, A634Ht, B37wx, C103DTrf, Fr27rhm, H99, Pa91, Va35, and W117Ht at 4/sup 0/C for 90 days which is more than double the typical survival time of callus. These studies show that proline accumulation increase the cold tolerance of regenerable maize callus.« less

Physiological diversity and trehalose accumulation in Schizosaccharomyces pombe strains isolated from spontaneous fermentations during the production of the artisanal Brazilian cachaça.

PubMed

Gomes, Fátima C O; Pataro, Carla; Guerra, Juliana B; Neves, Maria J; Corrêa, Soraya R; Moreira, Elizabeth S A; Rosa, Carlos A

2002-05-01

Twenty-seven Schizosaccharomyces pombe isolates from seven cachaça distilleries were tested for maximum temperature of growth and fermentation, osmotolerance, ethanol resistance, invertase production, and trehalose accumulation. Two isolates were selected for studies of trehalose accumulation under heat shock and ethanol stress. The S. pombe isolates were also characterized by RAPD-PCR. The isolates were able to grow and ferment at 41 degrees C, resisted concentrations of 10% ethanol, and grew on 50% glucose medium. Four isolates yielded invertase activity of more than 100 micromol of reducing sugar x mg(-1) x min(-1). The S. pombe isolates were able to accumulate trehalose during stationary phase. Two isolates, strains UFMG-A533 and UFMG-A1000, submitted to a 15 min heat shock, were able to accumulate high trehalose levels. Strain UFMG-A533 had a marked reduction in viability during heat shock, but strain UFMG-A1000 preserved a viability rate of almost 20% after 15 min at 48 degrees C. No clear correlation was observed between trehalose accumulation and cell survival during ethanol stress. Strain UFMG-A1000 had higher trehalose accumulation levels than strain UFMG-A533 under conditions of combined heat treatment and ethanol stress. Molecular analysis showed that some strains are maintained during the whole cachaça production period; using the RAPD-PCR profiles, it was possible to group the isolates according to their isolation sites.

Estimating Temporal Redistribution of Surface Melt Water into Upper Stratigraphy of the Juneau Icefield, Alaska

NASA Astrophysics Data System (ADS)

Wilner, J.; Smith, B.; Moore, T.; Campbell, S. W.; Slavin, B. V.; Hollander, J.; Wolf, J.

2015-12-01

The redistribution of winter accumulation from surface melt into firn or deeper layers (i.e. internal accumulation) remains a poorly understood component of glacier mass balance. Winter accumulation is usually quantified prior to summer melt, however the time window between accumulation and the onset of melt is minimal so this is not always possible. Studies which are initiated following the onset of summer melt either neglect sources of internal accumulation or attempt to estimate melt (and therefore winter accumulation uncertainty) through a variety of modeling methods. Here, we used ground-penetrating radar (GPR) repeat common midpoint (CMP) surveys with supporting common offset surveys, mass balance snow pits, and probing to estimate temporal changes in water content within the winter accumulation and firn layers of the southern Juneau Icefield, Alaska. In temperate glaciers, radio-wave velocity is primarily dependent on water content and snow or firn density. We assume density changes are temporally slow relative to water flow through the snow and firn pack, and therefore infer that changing radio-wave velocities measured by successive CMP surveys result from flux in surface melt through deeper layers. Preliminary CMP data yield radio-wave velocities of 0.15 to 0.2 m/ns in snowpack densities averaging 0.56 g cm-3, indicating partially to fully saturated snowpack (4-9% water content). Further spatial-temporal analysis of CMP surveys is being conducted. We recommend that repeat CMP surveys be conducted over a longer time frame to estimate stratigraphic water redistribution between the end of winter accumulation and maximum melt season. This information could be incorporated into surface energy balance models to further understanding of the influence of internal accumulation on glacier mass balance.

Insights into accumulation variability over the last 2000 years at James Ross Island, Antarctic Peninsula

NASA Astrophysics Data System (ADS)

Massam, A.; Mulvaney, R.; McConnell, J.; Abram, N.; Arienzo, M. M.; Whitehouse, P. L.

2016-12-01

The James Ross Island ice core, drilled to 364 m on the northern tip of the Antarctic Peninsula, preserves a climate record that spans beyond the Holocene period to the end of the last glacial maximum (LGM). Reanalysis of the ice core using high-resolution continuous flow analysis (CFA) highlighted errors in the identification of events of known age that had been used to constrain the earlier chronology. The new JRI2 chronology is annual layer counted to 300 years, with the remaining profile reconstructed using a new age-depth model that is tied to age horizons identified in the annual-layer counted WAIS Divide ice core record. An accurate age-depth profile requires reliable known-age horizons along the ice core profile. In addition, these allow us to determine a solution for the accumulation history and rate of compaction due to vertical strain. The accuracy of the known-age constraints used in JRI2 allows only a small uncertainty in the reconstruction of the most recent 2000 years of accumulation variability. Independently, the surface temperature profile has been estimated from the stable water isotope profile and calibrated to borehole temperature observations. We present the accumulation, vertical thinning and temperature history interpreted from the James Ross Island ice core for the most recent 2000 years. JRI2 reconstructions show accumulation variability on a decadal to centennial timescale up to 20% from the present-day mean annual accumulation rate of 0.63 m yr-1. Analysis of the accumulation profile for James Ross Island offers insight into the sensitivity of accumulation to a change in surface temperature, as well as the reliability of the assumed relationship between accumulation and surface temperature in climate reconstructions using stable water isotope proxies.

Strain accumulation and rotation in the Eastern California Shear Zone

USGS Publications Warehouse

Savage, J.C.; Gan, Weijun; Svarc, J.L.

2001-01-01

Although the Eastern California Shear Zone (ECSZ) (strike ???N25??W) does not quite coincide with a small circle drawn about the Pacific-North America pole of rotation, trilateration and GPS measurements demonstrate that the motion within the zone corresponds to right-lateral simple shear across a vertical plane (strike N33??W??5??) roughly parallel to the tangent to that local small circle (strike ???N40??W). If the simple shear is released by slip on faults subparallel to the shear zone, the accumulated rotation is also released, leaving no secular rotation. South of the Garlock fault the principal faults (e.g., Calico-Blackwater fault) strike ???N40??W, close enough to the strike of the vertical plane across which maximum right-lateral shear accumulates to almost wholly accommodate that accumulation of both strain and rotation by right-lateral slip. North of the Garlock fault dip slip as well as strike slip on the principal faults (strike ???N20??W) is required to accommodate the simple shear accumulation. In both cases the accumulated rotation is released with the shear strain. The Garlock fault, which transects the ECSZ, is not offset by north-northwest striking faults nor, despite geological evidence for long-term left-lateral slip, does it appear at the present time to be accumulating left-lateral simple shear strain across the fault due to slip at depth. Rather the motion is explained by right-lateral simple shear across the orthogonal ECSZ. Left-lateral slip on the Garlock fault will release the shear strain accumulating there but would augment the accumulating rotation, resulting in a secular clockwise rotation rate ???80 nrad yr-1 (4.6?? Myr-1).

Photovoltaic array: Power conditioner interface characteristics

NASA Technical Reports Server (NTRS)

Gonzalez, C. C.; Hill, G. M.; Ross, R. G., Jr.

1982-01-01

The electrical output (power, current, and voltage) of flat plate solar arrays changes constantly, due primarily to changes in cell temperature and irradiance level. As a result, array loads such as dc-to-ac power conditioners must be capable of accommodating widely varying input levels while maintaining operation at or near the maximum power point of the array. The array operating characteristics and extreme output limits necessary for the systematic design of array load interfaces under a wide variety of climatic conditions are studied. A number of interface parameters are examined, including optimum operating voltage, voltage energy, maximum power and current limits, and maximum open circuit voltage. The effect of array degradation and I-V curve fill factor or the array power conditioner interface is also discussed. Results are presented as normalized ratios of power conditioner parameters to array parameters, making the results universally applicable to a wide variety of system sizes, sites, and operating modes.

Metal(loid) accumulation in aquatic plants of a mining area: Potential for water quality biomonitoring and biogeochemical prospecting.

PubMed

Favas, Paulo J C; Pratas, João; Rodrigues, Nelson; D'Souza, Rohan; Varun, Mayank; Paul, Manoj S

2018-03-01

Aquatic bryophytes can accumulate extremely high levels of chemical elements because of their unique morphology and physiology which is markedly different from vascular plants. Four aquatic mosses-Fontinalis squamosa, Brachythecium rivulare, Platyhypnidium riparioides, Thamnobryum alopecurum-and a freshwater red alga Lemanea fluviatilis along with water samples from the streams of Góis mine region in Central Portugal were analyzed for 46 elements. Despite being below detection levels in the water samples, the elements Zr, V, Cr, Mo, Ru, Os, Rh, Ir, Pt, Ag, Ge and Bi were obtained in the plant samples. The moss T. alopecurum had the highest mean concentrations of 19 elements followed by B. rivulare (15 elements). Maximum accumulation of Rb, Ta and Au, however, was seen in the alga L. fluviatilis. Bioconcentration factors > 10 6 were obtained for a few metals. The investigation confirms that aquatic bryophytes can be suitable for water quality biomonitoring and biogeochemical prospecting in fresh water bodies owing to their high accumulative capacity of multi-elements from their aquatic ambient. Copyright © 2017 Elsevier Ltd. All rights reserved.

ESTIMATE OF SOLAR MAXIMUM USING THE 1-8 Å GEOSTATIONARY OPERATIONAL ENVIRONMENTAL SATELLITES X-RAY MEASUREMENTS

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

Winter, L. M.; Balasubramaniam, K. S., E-mail: lwinter@aer.com

We present an alternate method of determining the progression of the solar cycle through an analysis of the solar X-ray background. Our results are based on the NOAA Geostationary Operational Environmental Satellites (GOES) X-ray data in the 1-8 Å band from 1986 to the present, covering solar cycles 22, 23, and 24. The X-ray background level tracks the progression of the solar cycle through its maximum and minimum. Using the X-ray data, we can therefore make estimates of the solar cycle progression and the date of solar maximum. Based upon our analysis, we conclude that the Sun reached its hemisphere-averagedmore » maximum in solar cycle 24 in late 2013. This is within six months of the NOAA prediction of a maximum in spring 2013.« less

Atmospheric Radiation Measurement program climate research facility operations quarterly report.

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

Sisterson, D. L.; Decision and Information Sciences

2006-09-06

Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and monthmore » for the current year and (2) site and fiscal year dating back to 1998. The U.S. Department of Energy requires national user facilities to report time-based operating data. The requirements concern the actual hours of operation (ACTUAL); the estimated maximum operation or uptime goal (OPSMAX), which accounts for planned downtime; and the VARIANCE [1-(ACTUAL/OPSMAX)], which accounts for unplanned downtime. The OPSMAX time for the third quarter for the Southern Great Plains (SGP) site is 2,074.80 hours (0.95 x 2,184 hours this quarter). The OPSMAX for the North Slope Alaska (NSA) locale is 1,965.60 hours (0.90 x 2,184), and that for the Tropical Western Pacific (TWP) locale is 1,856.40 hours (0.85 x 2,184). The OPSMAX time for the ARM Mobile Facility (AMF) is 2,074.80 hours (0.95 x 2,184). The differences in OPSMAX performance reflect the complexity of local logistics and the frequency of extreme weather events. It is impractical to measure OPSMAX for each instrument or data stream. Data availability reported here refers to the average of the individual, continuous data streams that have been received by the Archive. Data not at the Archive are caused by downtime (scheduled or unplanned) of the individual instruments. Therefore, data availability is directly related to individual instrument uptime. Thus, the average percent of data in the Archive represents the average percent of the time (24 hours per day, 91 days for this quarter) the instruments were operating this quarter. Table 1 shows the accumulated maximum operation time (planned uptime), the actual hours of operation, and the variance (unplanned downtime) for the period April 1 through June 30, 2006, for the fixed and mobile sites. Although the AMF is currently up and running in Niamey, Niger, Africa, the AMF statistics are reported separately and not included in the aggregate average with the fixed sites. The third quarter comprises a total of 2,184 hours. For all fixed sites (especially the TWP locale) and the AMF, the actual data availability (and therefore actual hours of operation) exceeded the individual (and well as aggregate average of the fixed sites) operational goal for the third quarter of fiscal year (FY) 2006.« less

Anaerobic/oxic/anoxic granular sludge process as an effective nutrient removal process utilizing denitrifying polyphosphate-accumulating organisms.

PubMed

Kishida, Naohiro; Kim, Juhyun; Tsuneda, Satoshi; Sudo, Ryuichi

2006-07-01

In a biological nutrient removal (BNR) process, the utilization of denitrifying polyphosphate-accumulating organisms (DNPAOs) has many advantages such as effective use of organic carbon substrates and low sludge production. As a suitable process for the utilization of DNPAOs in BNR, an anaerobic/oxic/anoxic granular sludge (AOAGS) process was proposed in this study. In spite of performing aeration for nitrifying bacteria, the AOAGS process can create anaerobic/anoxic conditions suitable for the cultivation of DNPAOs because anoxic zones exist inside the granular sludge in the oxic phase. Thus, DNPAOs can coexist with nitrifying bacteria in a single reactor. In addition, the usability of DNPAOs in the reactor can be improved by adding the anoxic phase after the oxic phase. These characteristics enable the AOAGS process to attain effective removal of both nitrogen and phosphorus. When acetate-based synthetic wastewater (COD: 600 mg/L, NH4-N: 60 mg/L, PO(4)-P: 10 mg/L) was supplied to a laboratory-scale sequencing batch reactor under the operation of anaerobic/oxic/anoxic cycles, granular sludge with a diameter of 500 microm was successfully formed within 1 month. Although the removal of both nitrogen and phosphorus was almost complete at the end of the oxic phase, a short anoxic period subsequent to the oxic phase was necessary for further removal of nitrogen and phosphorus. As a result, effluent concentrations of NH(4)-N, NO(x)-N and PO(4)-P were always lower than 1 mg/L. It was found that penetration depth of oxygen inside the granular sludge was approximately 100 microm by microsensor measurements. In addition, from the microbiological analysis by fluorescence in situ hybridization, existence depth of polyphosphate-accumulating organisms was further than the maximum oxygen penetration depth. The water quality data, oxygen profiles and microbial community structure demonstrated that DNPAOs inside the granular sludge may be responsible for denitrification in the oxic phase, which enables effective nutrient removal in the AOAGS process.

Single-event and total-dose effects in geo-stationary transfer orbit during solar-activity maximum period measured by the Tsubasa satellite

NASA Astrophysics Data System (ADS)

Koshiishi, H.; Kimoto, Y.; Matsumoto, H.; Goka, T.

The Tsubasa satellite developed by the Japan Aerospace Exploration Agency was launched in Feb 2002 into Geo-stationary Transfer Orbit GTO Perigee 500km Apogee 36000km and had been operated well until Sep 2003 The objective of this satellite was to verify the function of commercial parts and new technologies of bus-system components in space Thus the on-board experiments were conducted in the more severe radiation environment of GTO rather than in Geo-stationary Earth Orbit GEO or Low Earth Orbit LEO The Space Environment Data Acquisition equipment SEDA on board the Tsubasa satellite had the Single-event Upset Monitor SUM and the DOSimeter DOS to evaluate influences on electronic devices caused by radiation environment that was also measured by the particle detectors of the SEDA the Standard DOse Monitor SDOM for measurements of light particles and the Heavy Ion Telescope HIT for measurements of heavy ions The SUM monitored single-event upsets and single-event latch-ups occurred in the test sample of two 64-Mbit DRAMs The DOS measured accumulated radiation dose at fifty-six locations in the body of the Tsubasa satellite Using the data obtained by these instruments single-event and total-dose effects in GTO during solar-activity maximum period especially their rapid changes due to solar flares and CMEs in the region from L 1 1 through L 11 is discussed in this paper

On the Theory of Accumulation of Hydrocarbons in a Dome Used to Eliminate a Technogenic Spill at the Bottom of the Ocean

NASA Astrophysics Data System (ADS)

Gimaltdinov, I. K.; Kil'dibaeva, S. R.

2018-01-01

Consideration is given to the operation of a dome separator installed at the bottom of the World Ocean and intended to eliminate the effects of technogenic spill of hydrocarbons. It is assumed that oil and gas (methane) escape from the damaged well on the ocean floor. Under the conditions of stable existence of a hydrate, a hydration sheath is formed on the surface of methane bubbles. To collect the entering hydrocarbons, a dome from a soft polyurethane shell is installed above the spill site, inside which the hydrocarbons are accumulated. In the regime of steady-state operation of the dome, provision is made for pumping out of hydrocarbons for transportation and further utilization. In the work, temperature fields of the hydrocarbon layers accumulated in the dome are investigated.

The importance of protection glasses during neuroangiographies: A study on radiation exposure at the lens of the primary operator.

PubMed

Tavares, J B; Sacadura-Leite, E; Matoso, T; Neto, L L; Biscoito, L; Campos, J; Sousa-Uva, A

2016-06-01

In interventional neuroradiology, few operators routinely use radiation protection glasses. Moreover, in most centers, radiation dose data only accounts for whole body dose without specific information on lens dose. In 2012, the International Commission on Radiological Protection advised that the threshold limit value for the lens should be 20 mSv/year instead of the previous 150 mSv/year limit. The purpose of this study was to compare the radiation dose in the operator's lens during real diagnostic and interventional neuroangiographies, either using or without lead protection glasses. Using the Educational Direct Dosimeter (EDD30 dosimeter), accumulated radiation dose in the lens was measured in 13 neuroangiographies: seven diagnostic and six interventional. Operators with and without radiation protection glasses were included and the sensor was placed near their left eye, closest to the radiation beam. Without glasses, the corrected mean dose of radiation in the lens was 8.02 µSv for diagnostic procedures and 168.57 µSv for interventional procedures. Using glasses, these values were reduced to 1.74 µSv and 33.24 µSv, respectively. Considering 20 mSv as the suggested annual limit of equivalent dose in the lens, neuroradiologists may perform up to 2,494 diagnostic procedures per year without protecting glasses, a number that increases to 11,494 when glasses are used consistently. Regarding intervention, a maximum of 119 procedures per year is advised if glasses are not used, whereas up to 602 procedures/year may be performed using this protection. Therefore, neuroradiologists should always wear radiation protection glasses. © The Author(s) 2016.

Tracking inorganic foulants irreversibly accumulated on low-pressure membranes for treating surface water.

PubMed

Yamamura, Hiroshi; Kimura, Katsuki; Higuchi, Kumiko; Watanabe, Yoshimasa; Ding, Qing; Hafuka, Akira

2015-12-15

While low-pressure membrane filtration processes (i.e., microfiltration and ultrafiltration) can offer precise filtration than sand filtration, they pose the problem of reduced efficiency due to membrane fouling. Although many studies have examined membrane fouling by organic substances, there is still not enough data available concerning membrane fouling by inorganic substances. The present research investigated changes in the amounts of inorganic components deposited on the surface of membrane filters over time using membrane specimens sampled thirteen times at arbitrary time intervals during pilot testing in order to determine the mechanism by which irreversible fouling by inorganic substances progresses. The experiments showed that the inorganic components that primarily contribute to irreversible fouling vary as filtration continues. It was discovered that, in the initial stage of operation, the main membrane-fouling substance was iron, whereas the primary membrane-fouling substances when operation finished were manganese, calcium, and silica. The amount of iron accumulated on the membrane increased up to the thirtieth day of operation, after which it reached a steady state. After the accumulation of iron became static, subsequent accumulation of manganese was observed. The fact that the removal rates of these inorganic components also increased gradually shows that the size of the exclusion pores of the membrane filter narrows as operation continues. Studying particle size distributions of inorganic components contained in source water revealed that while many iron particles are approximately the same size as membrane pores, the fraction of manganese particles slightly smaller than the pores in diameter was large. From these results, it is surmised that iron particles approximately the same size as the pores block them soon after the start of operation, and as the membrane pores narrow with the development of fouling, they become further blocked by manganese particles approximately the same size as the narrowed pores. Calcium and silica are assumed to accumulate on the membrane due to their cross-linking action and/or complex formation with organic substances such as humic compounds. The present research is the first to clearly show that the inorganic components that contribute to membrane fouling differ according to the stage of membrane fouling progression; the information obtained by this research should enable chemical cleaning or operational control in accordance with the stage of membrane fouling progression. Copyright © 2015 Elsevier Ltd. All rights reserved.

Maturation of Acorns of Cherrybark, Water, and Willow Oaks

Treesearch

F. T. Bonner

1974-01-01

Acorns of cherrybark, water, and willow oaks grew slowly but steadily in July and August and reached maximum size in September, when fats and carbohydrates, the major storage foods, accumulated rapidly. At physiological maturity in late October or early November, crude fat levels were 15 to 20 percent of seed dry weight and carbohydrates totaled 25 percent.

Identification and validation of a new source of low grain cadmium accumulation in durum wheat

USDA-ARS?s Scientific Manuscript database

Cadmium (Cd) is a heavy metal that has no known biological function and is toxic for many living organisms. The maximum level of Cd concentration allowed in the international market for wheat grain is 0.2 mg kg-1. Because phenotyping for Cd uptake is expensive and time consuming, molecular markers a...

A spline model of climate for the Western United States

Treesearch

Gerald E. Rehfeldt

2006-01-01

Monthly climate data of average, minimum, and maximum temperature and precipitation normalized for the period 1961 through 1990 were accumulated from approximately 3,000 weather stations in the Western United States and Southwestern Canada. About two-thirds of these observations were available from the weather services of the two countries while the remaining third...

Research on Substance Abuse: Alcohol, Drugs, Tobacco. Matrix No. 14.

ERIC Educational Resources Information Center

Robins, Lee N.

In the last few years, a vast amount of research has accumulated with respect to American children's use of legal and illicit drugs. This research has included cross-sectional studies (which have attempted to determine current drug usage, age of onset for each drug used, and maximum frequency of use in the lifetime); longitudinal studies (which…

Organochlorine pesticide residues in ground water of Thiruvallur district, India.

PubMed

Jayashree, R; Vasudevan, N

2007-05-01

Modern agriculture practices reveal an increase in use of pesticides and fertilizers to meet the food demand of increasing population which results in contamination of the environment. In India crop production increased to 100% but the cropping area has increased marginally by 20%. Pesticides have played a major role in achieving the maximum crop production, but maximum usage and accumulation of pesticide residues was highly detrimental to aquatic and other ecosystem. The present study was chosen to know the level of organochlorines contamination in ground water of Thiruvallur district, Tamil Nadu, India. The samples were highly contaminated with DDT, HCH, endosulfan and their derivatives. Among the HCH derivatives, Gamma HCH residues was found maximum of 9.8 microg/l in Arumbakkam open wells. Concentrations of pp-DDT and op-DDT were 14.3 microg/l and 0.8 microg/l. The maximum residue (15.9 microg/l) of endosulfan sulfate was recorded in Kandigai village bore well. The study showed that the ground water samples were highly contaminated with organochlorine residues.

STS upper stage operations

NASA Technical Reports Server (NTRS)

Kitchens, M. D.; Schnyer, A. D.

1977-01-01

Several design/development and operational approaches for STS upper stages are being pursued to realize maximum operational and economic benefits upon the introduction of the STS in the 1980s. The paper focuses special attention on safety operations, launch site operations and on-orbit operations.

Using Confidence Intervals and Recurrence Intervals to Determine Precipitation Delivery Mechanisms Responsible for Mass Wasting Events.

NASA Astrophysics Data System (ADS)

Ulizio, T. P.; Bilbrey, C.; Stoyanoff, N.; Dixon, J. L.

2015-12-01

Mass wasting events are geologic hazards that impact human life and property across a variety of landscapes. These movements can be triggered by tectonic activity, anomalous precipitation events, or both; acting to decrease the factor of safety ratio on a hillslope to the point of failure. There exists an active hazard landscape in the West Boulder River drainage of Park Co., MT in which the mechanisms of slope failure are unknown. It is known that region has not seen significant tectonic activity within the last decade, leaving anomalous precipitation events as the likely trigger for slope failures in the landscape. Precipitation can be delivered to a landscape via rainfall or snow; it was the aim of this study to determine the precipitation delivery mechanism most likely responsible for movements in the West Boulder drainage following the Jungle Wildfire of 2006. Data was compiled from four SNOTEL sites in the surrounding area, spanning 33 years, focusing on, but not limited to; maximum snow water equivalent (SWE) values in a water year, median SWE values on the date which maximum SWE was recorded in a water year, the total precipitation accumulated in a water year, etc. Means were computed and 99% confidence intervals were constructed around these means. Recurrence intervals and exceedance probabilities were computed for maximum SWE values and total precipitation accumulated in a water year to determine water years with anomalous precipitation. It was determined that the water year 2010-2011 received an anomalously high amount of SWE, and snow melt in the spring of this water year likely triggered recent mass waste movements. This data is further supported by Google Earth imagery, showing movements between 2009 and 2011. Return intervals for the maximum SWE value in 2010-11 for the Placer Basin SNOTEL site was 34 years, while return intervals for the Box Canyon and Monument Peak SNOTEL sites were 17.5 and 17 years respectively. Max SWE values lie outside the upper bound of the 99% confidence interval at all SNOTEL sites while precipitation accumulated in the form of rain is within the expected average, indicating an anomalously snow year and average amounts of rainfall during the same water year. This information can be used to better predict circumstances leading to slope failures in northern latitude alpine landscapes.

Thermoelectric integrated membrane evaporation water recovery technology

NASA Technical Reports Server (NTRS)

Roebelen, G. J., Jr.; Winkler, H. E.; Dehner, G. F.

1982-01-01

The recently developed Thermoelectric Integrated Membrane Evaporation Subsystem (TIMES) offers a highly competitive approach to water recovery from waste fluids for future on-orbit stations such as the Space Operations Center. Low power, compactness and gravity insensitive operation are featured in this vacuum distillation subsystem that combines a hollow fiber membrane evaporator with a thermoelectric heat pump. The hollow fiber elements provide positive liquid/gas phase control with no moving parts other than pumps and an accumulator, thus solving problems inherent in other reclamation subsystem designs. In an extensive test program, over 850 hours of operation were accumulated during which time high quality product water was recovered from both urine and wash water at an average steady state production rate of 2.2 pounds per hour.

Adenylate Energy Pool and Energy Charge in Maturing Rape Seeds 1

PubMed Central

Ching, Te May; Crane, Jim M.; Stamp, David L.

1974-01-01

A study of energy state and chemical composition of pod walls and seeds of maturing rape (Brassica napus L.) was conducted on two varieties, Victor and Gorczanski. Total adenosine phosphates, ATP, and adenylate energy charge increased with increasing cell number and cellular synthesis during the early stages, remained high at maximum dry weight accumulation and maximum substrate influx time, and decreased with ripening. A temporal control of energy supply and ATP concentration is evident in developing tissues with determined functions; whereas the association of a high energy charge and active cellular biosynthesis occurs only in tissues with a stabilized cell number. PMID:16658964

Viscoelastic/damage modeling of filament-wound spherical pressure vessels

NASA Technical Reports Server (NTRS)

Hackett, Robert M.; Dozier, Jan D.

1987-01-01

A model of the viscoelastic/damage response of a filament-wound spherical vessel used for long-term pressure containment is developed. The matrix material of the composite system is assumed to be linearly viscoelastic. Internal accumulated damage based upon a quadratic relationship between transverse modulus and maximum circumferential strain is postulated. The resulting nonlinear problem is solved by an iterative routine. The elastic-viscoelastic correspondence is employed to produce, in the Laplace domain, the associated elastic solution for the maximum circumferential strain which is inverted by the method of collocation to yield the time-dependent solution. Results obtained with the model are compared to experimental observations.

Nitrogen-removal performance and community structure of nitrifying bacteria under different aeration modes in an oxidation ditch.

PubMed

Guo, Chang-Zi; Fu, Wei; Chen, Xue-Mei; Peng, Dang-Cong; Jin, Peng-Kang

2013-07-01

Oxidation-ditch operation modes were simulated using sequencing batch reactors (SBRs) with alternate stirring and aerating. The nitrogen-removal efficiencies and nitrifying characteristics of two aeration modes, point aeration and step aeration, were investigated. Under the same air-supply capacity, oxygen dissolved more efficiently in the system with point aeration, forming a larger aerobic zone. The nitrifying effects were similar in point aeration and step aeration, where the average removal efficiencies of NH4(+) N were 98% and 96%, respectively. When the proportion of anoxic and oxic zones was 1, the average removal efficiencies of total nitrogen (TN) were 45% and 66% under point aeration and step aeration, respectively. Step aeration was more beneficial to both anoxic denitrification and simultaneous nitrification and denitrification (SND). The maximum specific ammonia-uptake rates (AUR) of point aeration and step aeration were 4.7 and 4.9 mg NH4(+)/(gMLVSS h), respectively, while the maximum specific nitrite-uptake rates (NUR) of the two systems were 7.4 and 5.3 mg NO2(-)-N/(gMLVSS h), respectively. The proportions of ammonia-oxidizing bacteria (AOB) to all bacteria were 5.1% under point aeration and 7.0% under step aeration, and the proportions of nitrite-oxidizing bacteria (NOB) reached 6.5% and 9.0% under point and step aeration, respectively. The dominant genera of AOB and NOB were Nitrosococcus and Nitrospira, which accounted for 90% and 91%, respectively, under point aeration, and the diversity of nitrifying bacteria was lower than under step aeration. Point aeration was selective of nitrifying bacteria. The abundance of NOB was greater than that of AOB in both of the operation modes, and complete transformation of NH4(+) N to NO3(-)-N was observed without NO2(-)-N accumulation. Copyright © 2013 Elsevier Ltd. All rights reserved.

Decrease of dynamic loads in mobile energy means

NASA Astrophysics Data System (ADS)

Polivaev, O. I.; Gorban, L. K.; Vorohobin, A. V.; Vedrinsky, O. S.

2018-03-01

The increase in the productivity of machine and tractor units is possible due to the increase in operating speeds, this leads to the emergence of increased dynamic loads in the system “engine-transmission-propulsion unit-soil”, which worsens the performance of machine-tractor aggregates. To reduce fluctuations in the “engine-transmission” system, special vibration dampers are used, which installed in close proximity to the engine and protect well the transmission from uneven engine operation; however, such dampers practically do not eliminate the oscillations of external loads. Reducing dynamic loads on the transmission and the mobile power engine (MPE) is an important issue directly related to improving the performance, reliability and durability of the tractor, as well as reducing the slippage of the drive wheels. In order to reduce effectively dynamic loads on the transmission and on the MPE, it is necessary to introduce resilient damping elements closer to the sources of oscillations, namely, to the driving wheels. At the same time, the elastic-damping element should provide accumulation of vibration energy caused by external influences and have a large energy capacity. The installation of an elastic-damping element in the final link of the tractor transmission ensures a reduction in the magnitude of external influences, thereby protecting the engine and transmission from large dynamic loads, and allows one to reduce the slippage of the propellers, which has a positive effect on the traction and energy characteristics of the tractor. Traction tests of the LTP-55 tractor on a concrete road showed that the use of an elasto-damping drive makes it possible to increase the maximum tractive power from 33.5 to 35.3 kW and to reduce the slipping of propellers by 12-30%, the specific fuel consumption by 6-10%. When driving on stubble, the use of an elastic-damping drive increases the maximum tractive power from 25 to 26 kW, reduces the skidding of propellers by 10-28%, and the specific fuel consumption by 10-12.5%.

Results of the Boeing/DOE DECC Phase 1 stirling engine project

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

STONE,KENNETH W.; CLARK,TERRY; NELVING,HANS

2000-03-02

Phase I of Boeing Company/DOE Dish Engine Critical Component (DECC) Project started in April of 1998 and was completed in 1999. The Phase I objectives, schedule, and test results are presented in this paper. These data shows the power, energy, and mirror performance are comparable to that when the hardware was first manufactured 15 years ago. During the Phase I and initial Phase II test period the on-sun system accumulated over 3,800 hours of solar-powered operating time, accumulated over 4,500 hours of concentrator solar tracking time, and generated over 50,000 kWh of grid-compatible electrical energy. The data also shows thatmore » the system was available 95 {percent} of the time when the sun's insolation level was above approximately 300 w/m{sup 2}, and achieved a daily energy efficiency between 20{percent} and 26{percent}. A second concentrator was refurbished during Phase I and accumulated over 2,200 hours of solar track time. A second Stirling engine operated 24 hours a day in a test cell in Sweden and accumulated over 6,000 test hours. Discussion of daily operation shows no major problems encountered during the testing that would prevent commercialization of the technology. Further analysis of the test data shows that system servicing with hydrogen, coolant and lubricating oil should not be a major O and M cost.« less

DSN telemetry system performance with convolutionally coded data using operational maximum-likelihood convolutional decoders

NASA Technical Reports Server (NTRS)

Benjauthrit, B.; Mulhall, B.; Madsen, B. D.; Alberda, M. E.

1976-01-01

The DSN telemetry system performance with convolutionally coded data using the operational maximum-likelihood convolutional decoder (MCD) being implemented in the Network is described. Data rates from 80 bps to 115.2 kbps and both S- and X-band receivers are reported. The results of both one- and two-way radio losses are included.

System for Repairing Cracks in Structures

NASA Technical Reports Server (NTRS)

Smith, Stephen W. (Inventor); Newman, John A. (Inventor); Piascik, Robert S. (Inventor); Glaessgen, Edward H. (Inventor)

2014-01-01

A first material with a known maximum temperature of operation is coated with a second material on at least one surface of the first material. The coating has a melting temperature that is greater than the maximum temperature of operation of the first material. The coating is heated to its melting temperature until the coating flows into any cracks in the first material's surface.

75 FR 78985 - County of DuPage; Notice of Preliminary Permit Application Accepted for Filing and Soliciting...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-17

... (upper reservoir) having a total storage capacity of 8,145 acre- feet at a normal maximum operating... reservoir) 250 feet below the bottom of the upper reservoir having a total/usable storage capacity of 7,465 acre-feet at normal maximum operation elevation of 210 feet msl; (5) a powerhouse with approximate...

A pulser-sustainer carbon monoxide electric-discharge supersonic laser

NASA Technical Reports Server (NTRS)

Monson, D. J.; Srinivasan, G.

1977-01-01

Operation of a CW CO electric-discharge supersonic laser with a pulser-sustainer discharge is described. High-power operation as well as independent control over electron energy and density are demonstrated. Maximum input power achieved to date is 100 kW. The maximum output power is 6 kW or 10% of the sustainer positive-column power. Much improved performance appears possible.

40 CFR Table 3 to Subpart Hhh of... - Operating Parameters To Be Monitored and Minimum Measurement and Recording Frequencies

Code of Federal Regulations, 2011 CFR

2011-07-01

... rural HMIWI HMIWI a with dry scrubber followed by fabric filter HMIWI a with wet scrubber HMIWI a with dry scrubber followed by fabric filter and wet scrubber Maximum operating parameters: Maximum charge... mercury (Hg) sorbent flow rate Hourly Once per hour ✔ ✔ Minimum pressure drop across the wet scrubber or...

Evaluation of recovery in lip closing pressure and occlusal force and contact area after orthognathic surgery.

PubMed

Ueki, Koichiro; Moroi, Akinori; Sotobori, Megumi; Ishihara, Yuri; Marukawa, Kohei; Iguchi, Ran; Kosaka, Akihiko; Ikawa, Hiroumi; Nakazawa, Ryuichi; Higuchi, Masatoshi

2014-10-01

The purpose of this study was to evaluate the relationship between lip closing force, occlusal contact area and occlusal force after orthognathic surgery in skeletal Class III patients. The subjects consisted of 54 patients (28 female and 26 male) diagnosed with mandibular prognathism who underwent sagittal split ramus osteotomy with and without Le Fort I osteotomy. Maximum and minimum lip closing forces, occlusal contact area and occlusal force were measured pre-operatively, 6 months and 1 year post-operative. Maximum and minimum lip closing forces, occlusal contact area and occlusal force increased with time after surgery, however a significant increase was not found in the occlusal contact area in women. In increased ratio (6 months/pre-operative and 1 year/pre-operative), the maximum lip closing force was significantly correlated with the occlusal contact area (P < 0.0001). This study suggested that orthognathic surgery could improve the occlusal force, contact area and lip closing force, and an increase ratio in maximum lip closing force was associated with an increased ratio in occlusal contact area. Copyright © 2014 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

14 CFR 65.47 - Maximum hours.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Maximum hours. 65.47 Section 65.47 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRMEN CERTIFICATION: AIRMEN OTHER THAN FLIGHT CREWMEMBERS Air Traffic Control Tower Operators § 65.47 Maximum hours...

MoS2-based passively Q-switched diode-pumped Nd:YAG laser at 946 nm

NASA Astrophysics Data System (ADS)

Lin, Haifeng; Zhu, Wenzhang.; Xiong, Feibing; Cai, Lie

2017-06-01

We demonstrate a passively Q-switched Nd: YAG quasi-three-level laser operating at 946 nm using MoS2 as saturable absorber. A maximum average output power of 210 mW is achieved at an absorbed pump power of 6.67 W with a slope efficiency of about 5.8%. The shortest pulse width and maximum pulse repetition frequency are measured to be 280 ns and 609 kHz, respectively. The maximum pulse energy and maximum pulse peak power are therefore estimated to be about 0.35 μJ and 1.23 W, respectively. This work represents the first MoS2-based Q-switched laser operating at 0.9 μm spectral region.

Spatial correlation in precipitation trends in the Brazilian Amazon

NASA Astrophysics Data System (ADS)

Buarque, Diogo Costa; Clarke, Robin T.; Mendes, Carlos Andre Bulhoes

2010-06-01

A geostatistical analysis of variables derived from Amazon daily precipitation records (trends in annual precipitation totals, trends in annual maximum precipitation accumulated over 1-5 days, trend in length of dry spell, trend in number of wet days per year) gave results that are consistent with those previously reported. Averaged over the Brazilian Amazon region as a whole, trends in annual maximum precipitations were slightly negative, the trend in the length of dry spell was slightly positive, and the trend in the number of wet days in the year was slightly negative. For trends in annual maximum precipitation accumulated over 1-5 days, spatial correlation between trends was found to extend up to a distance equivalent to at least half a degree of latitude or longitude, with some evidence of anisotropic correlation. Time trends in annual precipitation were found to be spatially correlated up to at least ten degrees of separation, in both W-E and S-N directions. Anisotropic spatial correlation was strongly evident in time trends in length of dry spell with much stronger evidence of spatial correlation in the W-E direction, extending up to at least five degrees of separation, than in the S-N. Because the time trends analyzed are shown to be spatially correlated, it is argued that methods at present widely used to test the statistical significance of climate trends over time lead to erroneous conclusions if spatial correlation is ignored, because records from different sites are assumed to be statistically independent.

Abiotic elicitation of gymnemic acid in the suspension cultures of Gymnema sylvestre.

PubMed

Ch, Bhuvaneswari; Rao, Kiranmayee; Gandi, Suryakala; Giri, Archana

2012-02-01

Elicitation is one of the few strategies that find commercial application in the enhancement of secondary metabolite production from plants as well as cell culture systems. Due to their immense medicinal value, production of saponins in suspension cultures has been attempted by many researchers. Gymnema sylvestre is a rich source of gymnemic acids (saponins) that find application in the treatment of diabetes. The present study is an attempt to evaluate the effect of various metal salts (cadmium chloride, mercuric chloride, silver nitrate, cupric chloride, cobaltous chloride and calcium chloride) in eliciting the response from G. sylvestre suspension cultures. The maximum gymnemic acid production in the suspensions was achieved on day 12 of culture, though the maximum biomass was obtained on day 16. Among the different salts, CdCl(2) gave maximum response (59.97 mg/gDCW) at 2 mM concentration after a 24 h time period, while, AgNO(3) gave the least response (18.35 mg/gDCW) on incubation of 48 h at 1 mM concentration, in terms of gymnemic acid accumulation. The accumulation of gymnemic acid was found to be dependent on treatment time and concentration of the elicitor. The enhanced gymnemic acid production shown by the suspensions in response to the metal salts indicates their role in evoking the plant defense mechanisms. These elicitation studies help in providing a platform for improved commercial supply of bioactive gymnemic acids.

Improvements of low-detection-limit filter-free fluorescence sensor developed by charge accumulation operation

NASA Astrophysics Data System (ADS)

Tanaka, Kiyotsugu; Choi, Yong Joon; Moriwaki, Yu; Hizawa, Takeshi; Iwata, Tatsuya; Dasai, Fumihiro; Kimura, Yasuyuki; Takahashi, Kazuhiro; Sawada, Kazuaki

2017-04-01

We developed a low-detection-limit filter-free fluorescence sensor by a charge accumulation technique. For charge accumulation, a floating diffusion amplifier (FDA), which included a floating diffusion capacitor, a transfer gate, and a source follower circuit, was used. To integrate CMOS circuits with the filter-free fluorescence sensor, we adopted a triple-well process to isolate transistors from the sensor on a single chip. We detected 0.1 nW fluorescence under the illumination of excitation light by 1.5 ms accumulation, which was one order of magnitude greater than that of a previous current detection sensor.

Chirped Pulse Spectrometer Operating at 200 GHz

NASA Astrophysics Data System (ADS)

Hindle, Francis; Bray, Cédric; Hickson, Kevin; Fontanari, Daniele; Mouelhi, Meriem; Cuisset, Arnaud; Mouret, Gaël; Bocquet, Robin

2018-01-01

The combination of electronic sources operating at high frequencies and modern microwave instrumentation has enabled the recent development of chirped pulse spectrometers for the millimetre and THz bands. This type of instrument can operate at high resolution which is particularly suited to gas-phase rotational spectroscopy. The construction of a chirped pulse spectrometer operating at 200 GHz is described in detail while attention is paid to the phase stability and the data accumulation over many cycles. Validation using carbonyl sulphide has allowed the detection limit of the instrument to be established as function of the accumulation. A large number of OCS transitions were identified using a 10-GHz chirped pulse and include the six most abundant isotopologues, the weakest line corresponding to the fundamental R(17) transition of 16O13C33S with a line strength of 4.3 × 10-26 cm-1/(molecule cm-2). The linearity of the system response for different degrees of data accumulation and transition line strength was confirmed over four orders of magnitudes. A simple analysis of the time-domain data was demonstrated to provide the line-broadening coefficient without the need for conversion by a Fourier transform. Finally, the pulse duration is discussed and optimal values are given for both Doppler-limited and collisional regimes.

Effect of multilayer substrate configuration in horizontal subsurface flow constructed wetlands: assessment of treatment performance, biofilm development, and solids accumulation.

PubMed

Ding, Yanli; Lyu, Tao; Bai, Shaoyuan; Li, Zhenling; Ding, Haijing; You, Shaohong; Xie, Qinglin

2018-01-01

This study investigates the influence of multilayer substrate configuration in horizontal subsurface flow constructed wetlands (HSCWs) on their treatment performance, biofilm development, and solids accumulation. Three pilot-scale HSCWs were built to treat campus sewage and have been operational for 3 years. The HSCWs included monolayer (CW1), three-layer (CW3), and six-layer (CW6) substrate configurations with hydraulic conductivity of the substrate increasing from the surface to bottom in the multilayer CWs. It was demonstrated the pollutant removal performance after a 3-year operation improved in the multilayer HSCWs (49-80%) compared to the monolayer HSCW (29-41%). Simultaneously, the multilayer HSCWs exhibited significant features that prevented clogging compared to the monolayer configuration. The amount of accumulated solids was notably higher in the monolayer CW compared to multilayer CWs. Further, multilayer HSCWs could delay clogging by providing higher biofilm development for organics removal and consequently, lesser solids accumulations. Principal component analysis strongly supported the visualization of the performance patterns in the present study and showed that multilayer substrate configuration, season, and sampling locations significantly influenced biofilm growth and solids accumulation. Finally, the present study provided important information to support the improved multilayer configured HSCW implication in the future.

Crystal accumulation in the Hanford Waste Treatment Plant high level waste melter: Summary of 2017 experiments

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

Fox, K.; Fowley, M.

A full-scale, transparent mock-up of the Hanford Tank Waste Treatment and Immobilization Project High Level Waste glass melter riser and pour spout has been constructed to allow for testing with visual feedback of particle settling, accumulation, and resuspension when operating with a controlled fraction of crystals in the glass melt. Room temperature operation with silicone oil and magnetite particles simulating molten glass and spinel crystals, respectively, allows for direct observation of flow patterns and settling patterns. The fluid and particle mixture is recycled within the system for each test.

Modeling Contamination Migration on the Chandra X-Ray Observatory - III

NASA Technical Reports Server (NTRS)

O'Dell, Stephen L.; Swartz, Douglas A.; Tice, Neil W.; Plucinsky, Paul P.; Grant, Catherine E.; Marshall, Herman L.; Vikhlinin, Alexy A.; Tennant, Allyn F.; Dahmer, Matthew T.

2015-01-01

During its first 16 years of operation, the cold (about -60 C) optical blocking filter of the Advanced CCD Imaging Spectrometer (ACIS), aboard the Chandra X-ray Observatory, has accumulated a growing layer of molecular contamination that attenuates low-energy x rays. Over the past few years, the accumulation rate, spatial distribution, and composition have changed. This evolution has motivated further analysis of contamination migration within and near the ACIS cavity, in part to evaluate potential bake-out scenarios intended to reduce the level of contamination. Keywords: X-ray astronomy, CCDs, contamination, modeling and simulation, spacecraft operations

Disinfection by-products in baby lettuce irrigated with electrolysed water.

PubMed

López-Gálvez, Francisco; Andújar, Silvia; Marín, Alicia; Tudela, Juan A; Allende, Ana; Gil, María I

2018-06-01

Irrigation water disinfection reduces the microbial load but it might lead to the formation and accumulation of disinfection by-products (DBPs) in the crop. If DBPs are present in the irrigation water, they can accumulate in the crop, particularly after the regrowth, and be affected by the postharvest handling such as washing and storage. To evaluate the potential accumulation of DBPs, baby lettuce was grown using irrigation water treated with electrolysed water (EW) in a commercial greenhouse over three consecutive harvests and regrowths. The impact of postharvest practices such as washing and storage on DBP content was also assessed. Use of EW caused the accumulation of chlorates in irrigation water (0.02-0.14 mg L -1 ), and in the fresh produce (0.05-0.10 mg kg -1 ). On the other hand, the disinfection treatment had minor impact regarding the presence of trihalomethanes (THMs) in water (0.3-8.7 μg L -1 max), and in baby lettuce (0.3-2.9 μg kg -1 max). Disinfection of irrigation water with EW caused the accumulation of chlorates in the crop reaching levels higher than the current maximum residual limit established in the EU legislation for leafy greens. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Three-compartment model for contaminant accumulation by semipermeable membrane devices

USGS Publications Warehouse

Gale, Robert W.

1998-01-01

Passive sampling of dissolved hydrophobic contaminants with lipid (triolein)-containing semipermeable membrane devices (SPMDs) has been gaining acceptance for environmental monitoring. Understanding of the accumulation process has employed a simple polymer film-control model of uptake by the polymer-enclosed lipid, while aqueous film control has been only briefly discussed. A more complete three-compartment model incorporating both aqueous film (turbulent-diffusive) and polymer film (diffusive) mass transfer is developed here and is fit to data from accumulation studies conducted in constant-concentration, flow-through dilutors. This model predicts aqueous film control of the whole device for moderate to high Kow compounds, rather than polymer film control. Uptake rates for phenanthrene and 2,2‘,5,5‘-tetrachlorobiphenyl were about 4.8 and 4.2 L/day/standard SPMD, respectively. Maximum 28 day SPMD concentration factors of 30 000 are predicted for solutes with log Kow values of >5.5. Effects of varying aqueous and polymer film thicknesses and solute diffusivities in the polymer film are modeled, and overall accumulation by the whole device is predicted to remain under aqueous film control, although accumulation in the triolein may be subject to polymer film control. The predicted half-life and integrative response of SPMDs to pulsed concentration events is proportional to log KSPMD.

Dissolved organic matter reduces algal accumulation of methylmercury

USGS Publications Warehouse

Luengen, Allison C.; Fisher, Nicholas S.; Bergamaschi, Brian A.

2012-01-01

Dissolved organic matter (DOM) significantly decreased accumulation of methylmercury (MeHg) by the diatom Cyclotella meneghiniana in laboratory experiments. Live diatom cells accumulated two to four times more MeHg than dead cells, indicating that accumulation may be partially an energy-requiring process. Methylmercury enrichment in diatoms relative to ambient water was measured by a volume concentration factor (VCF). Without added DOM, the maximum VCF was 32 x 104, and the average VCF (from 10 to 72 h) over all experiments was 12.6 x 104. At very low (1.5 mg/L) added DOM, VCFs dropped by approximately half. At very high (20 mg/L) added DOM, VCFs dropped 10-fold. Presumably, MeHg was bound to a variety of reduced sulfur sites on the DOM, making it unavailable for uptake. Diatoms accumulated significantly more MeHg when exposed to transphilic DOM extracts than hydrophobic ones. However, algal lysate, a labile type of DOM created by resuspending a marine diatom in freshwater, behaved similarly to a refractory DOM isolate from San Francisco Bay. Addition of 67 μM L-cysteine resulted in the largest drop in VCFs, to 0.28 x 104. Although the DOM composition influenced the availability of MeHg to some extent, total DOM concentration was the most important factor in determining algal bioaccumulation of MeHg.

Development of optimal medium content for bioelements accumulation in Bacopa monnieri (L.) in vitro culture.

PubMed

Łojewski, Maciej; Muszyńska, Bożena; Smalec, Agata; Reczyński, Witold; Opoka, Włodzimierz; Sułkowska-Ziaja, Katarzyna

2014-10-01

Bacopa monnieri is one of the most interesting plants from the Ayurveda system. The aims of present research were, basing on in vitro shoot culture of B. monnieri, to determine content and to evaluate the influence of physiologically important metabolites on the selected bioelements accumulation in biomass. The most significant increase in biomass production was observed in the culture medium enriched with 0.5 mg/L of anthranilic acid. In this medium also, the highest accumulation of Mg was noted. The highest concentration of iron was determined in B. monnieri in vitro culture enriched with 0.25 g/L of serine. The addition of L-tryptophan, magnesium sulfate, and zinc hydroaspartate caused only a small increase in the accumulation of copper in B. monnieri. Increase in Zn accumulation was obtained in biomass from in vitro culture of B. monnieri with the addition of magnesium sulfate and zinc hydroaspartate. In the case of Na, the maximum level of this element was in biomass from medium enriched with zinc hydroaspartate. Twofold increase in K concentration was obtained in biomass from cultures on medium with addition of serine and magnesium sulfate. The concentrations of Ca in biomass of all studied media were at the similar level.

Leaf-age and soil-plant relationships: key factors for reporting trace-elements hyperaccumulation by plants and design applications.

PubMed

Losfeld, Guillaume; L'Huillier, Laurent; Fogliani, Bruno; Mc Coy, Stéphane; Grison, Claude; Jaffré, Tanguy

2015-04-01

Relationships between the trace-elements (TE) content of plants and associated soil have been widely investigated especially to understand the ecology of TE hyperaccumulating species to develop applications using TE phytoextraction. Many studies have focused on the possibility of quantifying the soil TE fraction available to plants, and used bioconcentration (BC) as a measure of the plants ability to absorb TE. However, BC only offers a static view of the dynamic phenomenon of TE accumulation. Accumulation kinetics are required to fully account for TE distributions in plants. They are also crucial to design applications where maximum TE concentrations in plant leaves are needed. This paper provides a review of studies of BC (i.e. soil-plant relationships) and leaf-age in relation to TE hyperaccumulation. The paper focuses of Ni and Mn accumulators and hyperaccumulators from New Caledonia who were previously overlooked until recent Ecocatalysis applications emerged for such species. Updated data on Mn hyperaccumulators and accumulators from New Caledonia are also presented and advocate further investigation of the hyperaccumulation of this element. Results show that leaf-age should be considered in the design of sample collection and allowed the reclassification of Grevillea meisneri known previously as a Mn accumulator to a Mn hyperaccumulator.

Operation regimes of a dielectric laser accelerator

NASA Astrophysics Data System (ADS)

Hanuka, Adi; Schächter, Levi

2018-04-01

We investigate three operation regimes in dielectric laser driven accelerators: maximum efficiency, maximum charge, and maximum loaded gradient. We demonstrate, using a self-consistent approach, that loaded gradients of the order of 1 to 6 [GV/m], efficiencies of 20% to 80%, and electrons flux of 1014 [el/s] are feasible, without significant concerns regarding damage threshold fluence. The latter imposes that the total charge per squared wavelength is constant (a total of 106 per μm2). We conceive this configuration as a zero-order design that should be considered for the road map of future accelerators.

On Utilization of NEXRAD Scan Strategy Information to Infer Discrepancies Associated With Radar and Rain Gauge Surface Volumetric Rainfall Accumulations

NASA Technical Reports Server (NTRS)

Roy, Biswadev; Datta, Saswati; Jones, W. Linwood; Kasparis, Takis; Einaudi, Franco (Technical Monitor)

2000-01-01

To evaluate the Tropical Rainfall Measuring Mission (TRMM) monthly Ground Validation (GV) rain map, 42 quality controlled tipping bucket rain gauge data (1 minute interpolated rain rates) were utilized. We have compared the gauge data to the surface volumetric rainfall accumulation of NEXRAD reflectivity field, (converting to rain rates using a 0.5 dB resolution smooth Z-R table). The comparison was carried out from data collected at Melbourne, Florida during the month of July 98. GV operational level 3 (L3 monthly) accumulation algorithm was used to obtain surface volumetric accumulations for the radar. The gauge records were accumulated using the 1 minute interpolated rain rates while the radar Volume Scan (VOS) intervals remain less than or equal to 75 minutes. The correlation coefficient for the radar and gauge totals for the monthly time-scale remain at 0.93, however, a large difference was noted between the gauge and radar derived rain accumulation when the radar data interval is either 9 minute, or 10 minute. This difference in radar and gauge accumulation is being explained in terms of the radar scan strategy information. The discrepancy in terms of the Volume Coverage Pattern (VCP) of the NEXRAD is being reported where VCP mode is ascertained using the radar tilt angle information. Hourly radar and gauge accumulations have been computed using the present operational L3 method supplemented with a threshold period of +/- 5 minutes (based on a sensitivity analysis). These radar and gauge accumulations are subsequently improved using a radar hourly scan weighting factor (taking ratio of the radar scan frequency within a time bin to the 7436 total radar scans for the month). This GV procedure is further being improved by introducing a spatial smoothing method to yield reasonable bulk radar to gauge ratio for the hourly and daily scales.

Occurrence and distribution of brominated flame retardants and perfluoroalkyl substances in Australian landfill leachate and biosolids.

PubMed

Gallen, C; Drage, D; Kaserzon, S; Baduel, C; Gallen, M; Banks, A; Broomhall, S; Mueller, J F

2016-07-15

The levels of perfluroalkyl substances (PFASs), polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCDDs) were studied in Australian landfill leachate and biosolids. Leachate was collected from 13 landfill sites and biosolids were collected from 16 wastewater treatment plants (WWTPs), across Australia. Perfluorohexanoate (PFHxA) (12-5700ng/L) was the most abundant investigated persistent, bioaccumulative and toxic (PBT) chemical in leachate. With one exception, mean concentrations of PFASs were higher in leachate of operating landfills compared to closed landfills. Polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane isomers (HBCDDs) were detected typically at operating landfills in comparatively lower concentrations than the PFASs. Decabromodiphenyl ether (BDE-209) (<0.4-2300ng/g) and perfluoroctanesulfonate (PFOS) (

VISCEL: A general-purpose computer program for analysis of linear viscoelastic structures (user's manual), volume 1

NASA Technical Reports Server (NTRS)

Gupta, K. K.; Akyuz, F. A.; Heer, E.

1972-01-01

This program, an extension of the linear equilibrium problem solver ELAS, is an updated and extended version of its earlier form (written in FORTRAN 2 for the IBM 7094 computer). A synchronized material property concept utilizing incremental time steps and the finite element matrix displacement approach has been adopted for the current analysis. A special option enables employment of constant time steps in the logarithmic scale, thereby reducing computational efforts resulting from accumulative material memory effects. A wide variety of structures with elastic or viscoelastic material properties can be analyzed by VISCEL. The program is written in FORTRAN 5 language for the Univac 1108 computer operating under the EXEC 8 system. Dynamic storage allocation is automatically effected by the program, and the user may request up to 195K core memory in a 260K Univac 1108/EXEC 8 machine. The physical program VISCEL, consisting of about 7200 instructions, has four distinct links (segments), and the compiled program occupies a maximum of about 11700 words decimal of core storage.

Thermophilic biofiltration of benzene and toluene.

PubMed

Cho, Kyung-Suk; Yoo, Sun-Kyung; Ryu, Hee Wook

2007-12-01

In the current studies, we characterized the degradation of a hot mixture of benzene and toluene (BT) gases by a thermophilic biofilter using polyurethane as packing material and high-temperature compost as a microbial source. We also examined the effect of supplementing the biofilter with yeast extract (YE). We found that YE substantially enhanced microbial activity in the thermophilic biofilter. The degrading activity of the biofilter supplied with YE was stable during long-term operation (approximately 100 d) without accumulating excess biomass. The maximum elimination capacity (1,650 g x m(-3) h(-1)) in the biofilter supplemented with YE was 3.5 times higher than that in the biofilter without YE (470 g g x m(-3) h(-1)). At similar retention times, the capacity to eliminate BT for the YE-supplemented biofilter was higher than for previously reported mesophilic biofilters. Thus, thermophilic biofiltration can be used to degrade hydrophobic compounds such as a BT mixture. Finally, 16S rDNA polymerase chain reaction-DGGE (PCR-DGGE) fingerprinting revealed that the thermophilic bacteria in the biofilter included Rubrobacter sp. and Mycobacterium sp.

An atmospheric turbulence and telescope simulator for the development of AOLI

NASA Astrophysics Data System (ADS)

Puga, Marta; López, Roberto; King, David; Oscoz, Alejandro

2014-08-01

AOLI, Adaptive Optics Lucky Imager, is the next generation of extremely high resolution instruments in the optical range, combining the two more promising techniques: Adaptive optics and lucky imaging. The possibility of reaching fainter objects at maximum resolution implies a better use of weak energy on each lucky image. AOLI aims to achieve this by using an adaptive optics system to reduce the dispersion that seeing causes on the spot and therefore increasing the number of optimal images to accumulate, maximizing the efficiency of the lucky imaging technique. The complexity of developments in hardware, control and software for in-site telescope tests claim for a system to simulate the telescope performance. This paper outlines the requirements and a concept/preliminary design for the William Herschel Telescope (WHT) and atmospheric turbulence simulator. The design consists of pupil resemble, a variable intensity point source, phase plates and a focal plane mask to assist in the alignment, diagnostics and calibration of AOLI wavefront sensor, AO loop and science detectors, as well as enabling stand-alone test operation of AOLI.

Effects of various organic carbon sources on simultaneous V(V) reduction and bioelectricity generation in single chamber microbial fuel cells.

PubMed

Hao, Liting; Zhang, Baogang; Cheng, Ming; Feng, Chuanping

2016-02-01

Four ordinary carbon sources affecting V(V) reduction and bioelectricity generation in single chamber microbial fuel cells (MFCs) were investigated. Acetate supported highest maximum power density of 589.1mW/m(2), with highest V(V) removal efficiency of 77.6% during 12h operation, compared with glucose, citrate and soluble starch. Exorbitant initial V(V) concentration led to lower V(V) removal efficiencies and power outputs. Extra addition of organics had little effect on the improvement of MFCs performance. V(V) reduction and bioelectricity generation were enhanced and then suppressed by the increase of conductivity. The larger the external resistance, the higher the V(V) removal efficiencies and voltage outputs. High-throughput 16S rRNA gene pyrosequencing analysis implied the accumulation of Enterobacter which had the capabilities of V(V) reduction, electrochemical activity and fermentation, accompanied with other functional species as Pseudomonas, Spirochaeta, Sedimentibacter and Dysgonomonas. This study steps forward to remediate V(V) contaminated environment based on MFC technology. Copyright © 2015 Elsevier Ltd. All rights reserved.

Crop Row Detection in Maize Fields Inspired on the Human Visual Perception

PubMed Central

Romeo, J.; Pajares, G.; Montalvo, M.; Guerrero, J. M.; Guijarro, M.; Ribeiro, A.

2012-01-01

This paper proposes a new method, oriented to image real-time processing, for identifying crop rows in maize fields in the images. The vision system is designed to be installed onboard a mobile agricultural vehicle, that is, submitted to gyros, vibrations, and undesired movements. The images are captured under image perspective, being affected by the above undesired effects. The image processing consists of two main processes: image segmentation and crop row detection. The first one applies a threshold to separate green plants or pixels (crops and weeds) from the rest (soil, stones, and others). It is based on a fuzzy clustering process, which allows obtaining the threshold to be applied during the normal operation process. The crop row detection applies a method based on image perspective projection that searches for maximum accumulation of segmented green pixels along straight alignments. They determine the expected crop lines in the images. The method is robust enough to work under the above-mentioned undesired effects. It is favorably compared against the well-tested Hough transformation for line detection. PMID:22623899

Parametric design criteria of an updated thermoradiative cell operating at optimal states

NASA Astrophysics Data System (ADS)

Zhang, Xin; Peng, Wanli; Lin, Jian; Chen, Xiaohang; Chen, Jincan

2017-11-01

An updated mode of the thermoradiative cell (TRC) with sub-band gap and non-radiative losses is proposed, which can efficiently harvest moderate-temperature heat energy and convert a part of heat into electricity. It is found that when the TRC is operated between the heat source at 800 K and the environment at 300 K , its maximum power output density and efficiency can attain 1490 W m-2 and 27.2 % , respectively. Moreover, the effects of some key parameters including the band gap and voltage output on the performance of the TRC are discussed. The optimally working regions of the power density, efficiency, band gap, and voltage output are determined. The maximum efficiency and power output density of the TRC operated at different temperatures are calculated and compared with those of thermophotovoltaic cells (TPVCs) and thermionic energy converters (TECs), and consequently, it is revealed that the maximum efficiency of the TRC operated at the moderate-temperature range is much higher than that of the TEC or the TPVC and the maximum power output density of the TRC is larger than that of the TEC but smaller than that of the TPVC. Particularly, the TRC is manufactured more easily than the near-field TPVC possessing a nanoscale vacuum gap. The results obtained will be helpful for engineers to choose the semiconductor materials, design and manufacture TRCs, and control operative conditions.

Atmospheric Radiation Measurement program climate research facility operations quarterly report April 1 - June 30, 2007.

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

Sisterson, D. L.

2007-07-26

Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and monthmore » for the current year and (2) site and fiscal year (FY) dating back to 1998. The U.S. Department of Energy requires national user facilities to report time-based operating data. The requirements concern the actual hours of operation (ACTUAL); the estimated maximum operation or uptime goal (OPSMAX), which accounts for planned downtime; and the VARIANCE [1 - (ACTUAL/OPSMAX)], which accounts for unplanned downtime. The OPSMAX time for the third quarter of FY 2007 for the Southern Great Plains (SGP) site is 2,074.8 hours (0.95 x 2,184 hours this quarter). The OPSMAX for the North Slope Alaska (NSA) locale is 1,965.6 hours (0.90 x 2,184), and that for the Tropical Western Pacific (TWP) locale is 1,856.4 hours (0.85 x 2,184). The OPSMAX time for the ARM Mobile Facility (AMF) is 2,074.8 hours (0.95 x 2,184). The differences in OPSMAX performance reflect the complexity of local logistics and the frequency of extreme weather events. It is impractical to measure OPSMAX for each instrument or data stream. Data availability reported here refers to the average of the individual, continuous data streams that have been received by the Archive. Data not at the Archive are caused by downtime (scheduled or unplanned) of the individual instruments. Therefore, data availability is directly related to individual instrument uptime. Thus, the average percent of data in the Archive represents the average percent of the time (24 hours per day, 91 days for this quarter) the instruments were operating this quarter. Table 1 shows the accumulated maximum operation time (planned uptime), the actual hours of operation, and the variance (unplanned downtime) for the period April 1 through June 30, 2007, for the fixed sites only. The AMF has been deployed to Germany and is operational this quarter. The third quarter comprises a total of 2,184 hours. Although the average exceeded our goal this quarter, there were cash flow issues resulting from Continuing Resolution early in the period that did not allow for timely instrument repairs that kept our statistics lower than past quarters at all sites. The low NSA numbers resulted from missing MFRSR data this spring that appears to be recoverable but not available at the Archive at the time of this report.« less

Atmospheric Radiation Measurement program climate research facilities quarterly report April 1 - June 30, 2009.

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

Sisterson, D. L.

2009-07-14

Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near-real time. Raw and processed data are then sent approximately daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and monthmore » for the current year and (2) site and fiscal year (FY) dating back to 1998. The U.S. Department of Energy (DOE) requires national user facilities to report time-based operating data. The requirements concern the actual hours of operation (ACTUAL); the estimated maximum operation or uptime goal (OPSMAX), which accounts for planned downtime; and the VARIANCE [1 - (ACTUAL/OPSMAX)], which accounts for unplanned downtime. The OPSMAX time for the third quarter of FY 2009 for the Southern Great Plains (SGP) site is 2,074.80 hours (0.95 x 2,184 hours this quarter); for the North Slope Alaska (NSA) locale it is 1,965.60 hours (0.90 x 2,184); and for the Tropical Western Pacific (TWP) locale it is 1,856.40 hours (0.85 x 2,184). The ARM Mobile Facility (AMF) was officially operational May 1 in Graciosa Island, the Azores, Portugal, so the OPSMAX time this quarter is 1390.80 hours (0.95 x 1464). The differences in OPSMAX performance reflect the complexity of local logistics and the frequency of extreme weather events. It is impractical to measure OPSMAX for each instrument or data stream. Data availability reported here refers to the average of the individual, continuous data streams that have been received by the Archive. Data not at the Archive are caused by downtime (scheduled or unplanned) of the individual instruments. Therefore, data availability is directly related to individual instrument uptime. Thus, the average percentage of data in the Archive represents the average percentage of the time (24 hours per day, 91 days for this quarter) the instruments were operating this quarter. Table 1 shows the accumulated maximum operation time (planned uptime), actual hours of operation, and variance (unplanned downtime) for April 1 - June 30, 2009, for the fixed sites. Because the AMF operates episodically, the AMF statistics are reported separately and are not included in the aggregate average with the fixed sites. The AMF statistics for this reporting period were not available at the time of this report. The third quarter comprises a total of 2,184 hours for the fixed sites. The average well exceeded our goal this quarter.« less

Soil Carbon Sequestration and Land-Use Change: Processes and Potential

DOE Data Explorer

Post, W. M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Kwon, K. C. [Tuskeegee University, Tuskeegee, AL (United States)

2005-01-01

When agricultural land is no longer used for cultivation and allowed to revert to natural vegetation or replanted to perennial vegetation, soil organic carbon can accumulate. This accumulation process essentially reverses some of the effects responsible for soil organic carbon losses from when the land was converted from perennial vegetation. We discuss the essential elements of what is known about soil organic matter dynamics that may result in enhanced soil carbon sequestration with changes in land-use and soil management. We review literature that reports changes in soil organic carbon after changes in land-use that favour carbon accumulation. This data summary provides a guide to approximate rates of SOC sequestration that are possible with management, and indicates the relative importance of some factors that influence the rates of organic carbon sequestration in soil. There is a large variation in the length of time for and the rate at which carbon may accumulate in soil, related to the productivity of the recovering vegetation, physical and biological conditions in the soil, and the past history of soil organic carbon inputs and physical disturbance. Maximum rates of C accumulation during the early aggrading stage of perennial vegetation growth, while substantial, are usually much less than 100g C m–2 y–1. Average rates of accumulation are similar for forest or grassland establishment: 33.8 g C m–2 y–1 and 33.2 g C m–2 y–1, respectively. These observed rates of soil organic C accumulation, when combined with the small amount of land area involved, are insufficient to account for a significant fraction of the missing C in the global carbon cycle as accumulating in the soils of formerly agricultural land.

Flow field induced particle accumulation inside droplets in rectangular channels.

PubMed

Hein, Michael; Moskopp, Michael; Seemann, Ralf

2015-07-07

Particle concentration is a basic operation needed to perform washing steps or to improve subsequent analysis in many (bio)-chemical assays. In this article we present field free, hydrodynamic accumulation of particles and cells in droplets flowing within rectangular micro-channels. Depending on droplet velocity, particles either accumulate at the rear of the droplet or are dispersed over the entire droplet cross-section. We show that the observed particle accumulation behavior can be understood by a coupling of particle sedimentation to the internal flow field of the droplet. The changing accumulation patterns are explained by a qualitative change of the internal flow field. The topological change of the internal flow field, however, is explained by the evolution of the droplet shape with increasing droplet velocity altering the friction with the channel walls. In addition, we demonstrate that accumulated particles can be concentrated, removing excess dispersed phase by splitting the droplet at a simple channel junction.

Method of operating a thermoelectric generator

DOEpatents

Reynolds, Michael G; Cowgill, Joshua D

2013-11-05

A method for operating a thermoelectric generator supplying a variable-load component includes commanding the variable-load component to operate at a first output and determining a first load current and a first load voltage to the variable-load component while operating at the commanded first output. The method also includes commanding the variable-load component to operate at a second output and determining a second load current and a second load voltage to the variable-load component while operating at the commanded second output. The method includes calculating a maximum power output of the thermoelectric generator from the determined first load current and voltage and the determined second load current and voltage, and commanding the variable-load component to operate at a third output. The commanded third output is configured to draw the calculated maximum power output from the thermoelectric generator.

Estimating the risk of cyanobacterial occurrence using an index integrating meteorological factors: application to drinking water production.

PubMed

Ndong, Mouhamed; Bird, David; Nguyen-Quang, Tri; de Boutray, Marie-Laure; Zamyadi, Arash; Vinçon-Leite, Brigitte; Lemaire, Bruno J; Prévost, Michèle; Dorner, Sarah

2014-06-01

The sudden appearance of toxic cyanobacteria (CB) blooms is still largely unpredictable in waters worldwide. Many post-hoc explanations for CB bloom occurrence relating to physical and biochemical conditions in lakes have been developed. As potentially toxic CB can accumulate in drinking water treatment plants and disrupt water treatment, there is a need for water treatment operators to determine whether conditions are favourable for the proliferation and accumulation of CB in source waters in order to adjust drinking water treatment accordingly. Thus, a new methodology with locally adaptable variables is proposed in order to have a single index, f(p), related to various environmental factors such as temperature, wind speed and direction. The index is used in conjunction with real time monitoring data to determine the probability of CB occurrence in relation to meteorological factors, and was tested at a drinking water intake in Missisquoi Bay, a shallow transboundary bay in Lake Champlain, Québec, Canada. These environmental factors alone were able to explain a maximum probability of 68% that a CB bloom would occur at the drinking water treatment plant. Nutrient limitation also influences CB blooms and intense blooms only occurred when the dissolved inorganic nitrogen (DIN) to total phosphorus (TP) mass ratio was below 3. Additional monitoring of DIN and TP could be considered for these source waters prone to cyanobacterial blooms to determine periods of favourable growth. Real time monitoring and the use of the index could permit an adequate and timely response to CB blooms in drinking water sources. Copyright © 2014 Elsevier Ltd. All rights reserved.

Silt and gas accumulation beneath an artificial recharge spreading basin, Southwestern Utah, U.S.A.

USGS Publications Warehouse

Heilweil, V.M.; Solomon, D.K.; Ortiz, G.

2009-01-01

Sand Hollow Reservoir in southwestern Utah, USA, is operated for both surface-water storage and artificial recharge to the underlying Navajo Sandstone. The total volume of estimated artificial recharge between 2002 and 2007 is 85 million cubic meters (69,000 acre-feet). Since 2002, artificial recharge rates have generally been declining and are inversely correlated with the increasing surface area of the reservoir. Permeability testing of core samples retrieved from beneath the reservoir indicates that this decline may not be due to silt accumulation. Artificial recharge rates also show much seasonal variability. Calculations of apparent intrinsic permeability show that these variations can only partly be explained by variation in water viscosity associated with seasonal changes in water temperature. Sporadic seasonal trends in recharge rates and intrinsic permeability during 2002-2004 could be associated with the large fluctuations in reservoir elevation and wetted area. From 2005 through 2007, the reservoir was mostly full and there has been a more consistent seasonal pattern of minimum recharge rates during the summer and maximum rates during the autumn. Total dissolved-gas pressure measurements indicate the presence of biogenic gas bubbles in the shallow sediments beneath the shallower parts of Sand Hollow Reservoir when the water is warmer. Permeability reduction associated with this gas clogging may contribute to the decrease in artificial recharge rates during the spring and summer, with a subsequently increasing recharge rates in the autumn associated with a decline in volume of gas bubbles. Other possible causes for seasonal variation in artificial recharge rates require further investigation.

21 CFR 1050.10 - Ultrasonic therapy products.

Code of Federal Regulations, 2014 CFR

2014-04-01

... greater than 5 percent of the spatial-maximum intensity in that plane. (4) Beam nonuniformity ratio means..., operation controls, and a cabinet to house these components. (17) Maximum beam nonuniformity ratio means the maximum value of the beam nonuniformity ratio characteristic of a model of an ultrasonic therapy product...

21 CFR 1050.10 - Ultrasonic therapy products.

Code of Federal Regulations, 2012 CFR

2012-04-01

... greater than 5 percent of the spatial-maximum intensity in that plane. (4) Beam nonuniformity ratio means..., operation controls, and a cabinet to house these components. (17) Maximum beam nonuniformity ratio means the maximum value of the beam nonuniformity ratio characteristic of a model of an ultrasonic therapy product...

21 CFR 1050.10 - Ultrasonic therapy products.

Code of Federal Regulations, 2013 CFR

2013-04-01

... greater than 5 percent of the spatial-maximum intensity in that plane. (4) Beam nonuniformity ratio means..., operation controls, and a cabinet to house these components. (17) Maximum beam nonuniformity ratio means the maximum value of the beam nonuniformity ratio characteristic of a model of an ultrasonic therapy product...

21 CFR 1050.10 - Ultrasonic therapy products.

Code of Federal Regulations, 2011 CFR

2011-04-01

... greater than 5 percent of the spatial-maximum intensity in that plane. (4) Beam nonuniformity ratio means..., operation controls, and a cabinet to house these components. (17) Maximum beam nonuniformity ratio means the maximum value of the beam nonuniformity ratio characteristic of a model of an ultrasonic therapy product...

21 CFR 1050.10 - Ultrasonic therapy products.

Code of Federal Regulations, 2010 CFR

2010-04-01

... greater than 5 percent of the spatial-maximum intensity in that plane. (4) Beam nonuniformity ratio means..., operation controls, and a cabinet to house these components. (17) Maximum beam nonuniformity ratio means the maximum value of the beam nonuniformity ratio characteristic of a model of an ultrasonic therapy product...

Construction of a test bench for closed die forging

NASA Astrophysics Data System (ADS)

Batit, G.; Kaczmarek, B.; Ravassard, P.

1984-03-01

A swan neck press was equipped with hydraulic jacks to enable it to press and forge complex shapes in closed dies in one operation without wasting metal. Maximum closing stress is 250 kN, maximum pressing stress is 250 kN, maximum forging stress is 70 kN.

40 CFR Table 4 to Subpart Ooo of... - Operating Parameter Levels

Code of Federal Regulations, 2012 CFR

2012-07-01

... temperature Maximum temperature Carbon absorber Total regeneration steam or nitrogen flow, or pressure (gauge or absolute) a during carbon bed regeneration cycle; and temperature of the carbon bed after regeneration (and within 15 minutes of completing any cooling cycle(s)) Maximum flow or pressure; and maximum...

An analysis of the development of cauliflower seed as a model to improve the molecular mechanism of abiotic stress tolerance in cauliflower artificial seeds.

PubMed

Rihan, Hail Z; Al-Issawi, Mohammed; Fuller, Michael P

2017-07-01

The development stages of conventional cauliflower seeds were studied and the accumulation of dehydrin proteins through the maturation stages was investigated with the aim of identifying methods to improve the viability of artificial seeds of cauliflower. While carbohydrate, ash and lipids increased throughout the development of cauliflower traditional seeds, proteins increased with the development of seed and reached the maximum level after 75 days of pollination, however, the level of protein started to decrease after that. A significant increase in the accumulation of small size dehydrin proteins (12, 17, 26 KDa) was observed during the development of cauliflower seeds. Several experiments were conducted in order to increase the accumulation of important dehydrin proteins in cauliflower microshoots (artificial seeds). Mannitol and ABA (Absisic acid) increased the accumulation of dehydrins in cauliflower microshoots while cold acclimation did not have a significant impact on the accumulation of these proteins. Molybdenum treatments had a negative impact on dehydrin accumulation. Dehydrins have an important role in the drought tolerance of seeds and, therefore, the current research helps to improve the accumulation of these proteins in cauliflower artificial seeds. This in turns improves the quality of these artificial seeds. The current results suggest that dehydrins do not play an important role in cold tolerance of cauliflower artificial seeds. This study could have an important role in improving the understanding of the molecular mechanism of abiotic stress tolerance in plants. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Multilinear approach to the precipitation-lightning relationship: a case study of summer local electrical storms in the northern part of Spain during 2002-2009 period

NASA Astrophysics Data System (ADS)

Herrero, I.; Ezcurra, A.; Areitio, J.; Diaz-Argandoña, J.; Ibarra-Berastegi, G.; Saenz, J.

2013-11-01

Storms developed under local instability conditions are studied in the Spanish Basque region with the aim of establishing precipitation-lightning relationships. Those situations may produce, in some cases, flash flood. Data used correspond to daily rain depth (mm) and the number of CG flashes in the area. Rain and lightning are found to be weakly correlated on a daily basis, a fact that seems related to the existence of opposite gradients in their geographical distribution. Rain anomalies, defined as the difference between observed and estimated rain depth based on CG flashes, are analysed by PCA method. Results show a first EOF explaining 50% of the variability that linearly relates the rain anomalies observed each day and that confirms their spatial structure. Based on those results, a multilinear expression has been developed to estimate the rain accumulated daily in the network based on the CG flashes registered in the area. Moreover, accumulates and maximum values of rain are found to be strongly correlated, therefore making the multilinear expression a useful tool to estimate maximum precipitation during those kind of storms.

The Elicitation Effect of Pathogenic Fungi on Trichodermin Production by Trichoderma brevicompactum

PubMed Central

Shentu, Xu-Ping; Liu, Wei-Ping; Zhan, Xiao-Huan; Yu, Xiao-Ping; Zhang, Chuan-Xi

2013-01-01

The effects of six species of phytopathogenic fungi mycelia as elicitors on trichodermin yield by Trichoderma brevicompactum were investigated. Neither nonviable nor viable mycelia of Botrytis cinerea, Alternaria solani, Colletotrichum lindemuthianum, and Thanatephorus cucumeris demonstrated any elicitation on the accumulation of trichodermin. However, the production of trichodermin was increased by the presence of viable/nonviable Rhizoctonia solani and Fusarium oxysporum mycelia. The strongest elicitation effect was found at the presence of nonviable R. solani. At the presence of nonviable R. solani, the maximum yield of trichodermin (144.55 mg/L) was significantly higher than the Control (67.8 mg/L), and the cultivation time to obtain the maximum yield of trichodermin decreased from 72 h to 60 h. No difference of trichodermin accumulation was observed by changing the concentration of nonviable R. solani from 0.1 to 1.6 g/L. It was observed that the optimum time for adding nonviable R. solani is immediately after inoculation. The diameter of T. brevicompactum mycelial globule after 72 h cultivation with nonviable R. solani elicitor was smaller than that of the Control. PMID:24385883

Enhanced production of short-chain fatty acid from food waste stimulated by alkyl polyglycosides and its mechanism.

PubMed

Zhao, Jianwei; Yang, Qi; Li, Xiaoming; Wang, Dongbo; Luo, Kun; Zhong, Yu; Xu, Qiuxiang; Zeng, Guangming

2015-12-01

Short-chain fatty acids (SCFAs) are the valuable products derived from the anaerobic fermentation of organic solid waste. However, SCFAs yield was limited by the worse solubilization and hydrolysis of particulate organic matter, and rapid consumption of organic acid by methanogens. In this study, an efficient and green strategy, i.e. adding biosurfactant alkyl polyglycosides (APG) into anaerobic fermentation system, was applied to enhance SCFAs production from food waste. Experimental results showed that APG not only greatly improved SCFAs production but also shortened the fermentation time for the maximum SCFAs accumulation. The SCFAs yield at optimal APG dosage 0.2g/g TS (total solid) reached 37.2g/L, which was 3.1-fold of that in blank. Meanwhile, the time to accumulate the maximum SCFAs in the presence of APG was shortened from day 14 to day 6. The activities of key enzymes such as hydrolytic and acid-forming enzymes were greatly promoted due to the presence of APG. These results demonstrated that the enhanced mechanism of SCFAs production should be attributed to the acceleration of solubilization and hydrolysis, enhancement of acidification and inhibition of methanogenesis by APG. Copyright © 2015 Elsevier Ltd. All rights reserved.

Biosynthesis of phenolic compounds inVitis vinifera cell suspension cultures: Study on hydroxycinnamoyl CoA:ligase.

PubMed

Lotfy, S; Lofty, S; Fleuriet, A; Ramos, T; Macheix, J J

1989-02-01

In cell suspensions cultures from grape berry pulp (Vitis vinifera cv. Gamay fréaux)hydroxycinnamoyl CoA ligase (CoAL) displayed maximum activity (100 %) forp-coumaric acid and then, in decreasing order, for ferulic acid (81.3 %) and caffeic acid (60.4 %). No activity was detected with sinapic and cinnamic acids. The changes in CoAL activity during the growth cycle of the culture displayed two peaks : the highest (6 h after subculturing) was linked with a strong increase in protein caused by dilution ; the second was weaker and occurred on the 7th day of culture.Grape cell suspension accumulated mainly peonidin (Pn) and cyanidin (Cy) glucosides (Pn 3-glucoside, Cy 3-glucoside, Pn 3-acetylglucoside, Pn 3-caffeylglucoside, Pn 3-p-coumarylglucoside, and Cy 3-p-coumarylglucoside). Maximum accumulation of anthocyanins was associated with the exponential growth phase of the culture and might be the result of the substantial increase in CoAL activity resulting from the effect of dilution. The second enzyme activity peak was probably oriented towards the acylation of anthocyanins since the percentage of acylated forms increased with time after subculturing.

Synthesis and Characterization of Water-Soluble Polythiophene Derivatives for Cell Imaging

NASA Astrophysics Data System (ADS)

Wang, Fengyan; Li, Meng; Wang, Bing; Zhang, Jiangyan; Cheng, Yongqiang; Liu, Libing; Lv, Fengting; Wang, Shu

2015-01-01

In this work, four water-soluble polythiophene derivatives (PT, PT-DDA, PT-ADA, and PT-ADA-PPR) with different pendant moieties were synthesized via oxidative copolymerization by FeCl3. By increasing the hydrophobic ability of side chain moieties, there is a gradually blue shift for the maximum absorption wavelength and red shift for the maximum emission wavelength, a reducing trend for fluorescence quantum yields, a growing trend for Stokes shift, and an increasing trend for the mean sizes in the order of PT, PT-ADA, and PT-DDA. All the synthesized polymers show low toxicity and good photostability and accumulate in the lysosomes of A549 cells. Furthermore, the introduction of porphyrin group to PT-ADA side chain (PT-ADA-PPR) broadens the absorption and emission ranges of PT-ADA. PT-ADA-PPR could be excited at two different excitation wavelengths (488 nm and 559 nm) and exhibits two emission pathways, and dual-color fluorescence images (orange and red) of PT-ADA-PPR accumulated in A549 cells are observed. Thus, PT-ADA-PPR could be used as an excellent dual-color fluorescent and lysosome-specific imaging material.

Long-range wind monitoring in real time with optimized coherent lidar

NASA Astrophysics Data System (ADS)

Dolfi-Bouteyre, Agnes; Canat, Guillaume; Lombard, Laurent; Valla, Matthieu; Durécu, Anne; Besson, Claudine

2017-03-01

Two important enabling technologies for pulsed coherent detection wind lidar are the laser and real-time signal processing. In particular, fiber laser is limited in peak power by nonlinear effects, such as stimulated Brillouin scattering (SBS). We report on various technologies that have been developed to mitigate SBS and increase peak power in 1.5-μm fiber lasers, such as special large mode area fiber designs or strain management. Range-resolved wind profiles up to a record range of 16 km within 0.1-s averaging time have been obtained thanks to those high-peak power fiber lasers. At long range, the lidar signal gets much weaker than the noise and special care is required to extract the Doppler peak from the spectral noise. To optimize real-time processing for weak carrier-to-noise ratio signal, we have studied various Doppler mean frequency estimators (MFE) and the influence of data accumulation on outliers occurrence. Five real-time MFEs (maximum, centroid, matched filter, maximum likelihood, and polynomial fit) have been compared in terms of error and processing time using lidar experimental data. MFE errors and data accumulation limits are established using a spectral method.

49 CFR Appendix A to Part 213 - Maximum Allowable Curving Speeds

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 4 2011-10-01 2011-10-01 false Maximum Allowable Curving Speeds A Appendix A to...—Maximum Allowable Curving Speeds Table 1—Three Inches Unbalance [Elevation of outer rail (inches)] Degree of curvature 0 1/2 1 11/2 2 21/2 3 31/2 4 41/2 5 51/2 6 (12) Maximum allowable operating speed (mph...

49 CFR Appendix A to Part 213 - Maximum Allowable Curving Speeds

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Maximum Allowable Curving Speeds A Appendix A to...—Maximum Allowable Curving Speeds Table 1—Three Inches Unbalance [Elevation of outer rail (inches)] Degree of curvature 0 1/2 1 11/2 2 21/2 3 31/2 4 41/2 5 51/2 6 (12) Maximum allowable operating speed (mph...

Determining collective barrier operation skew in a parallel computer

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

Faraj, Daniel A.

2015-11-24

Determining collective barrier operation skew in a parallel computer that includes a number of compute nodes organized into an operational group includes: for each of the nodes until each node has been selected as a delayed node: selecting one of the nodes as a delayed node; entering, by each node other than the delayed node, a collective barrier operation; entering, after a delay by the delayed node, the collective barrier operation; receiving an exit signal from a root of the collective barrier operation; and measuring, for the delayed node, a barrier completion time. The barrier operation skew is calculated by:more » identifying, from the compute nodes' barrier completion times, a maximum barrier completion time and a minimum barrier completion time and calculating the barrier operation skew as the difference of the maximum and the minimum barrier completion time.« less

Determining collective barrier operation skew in a parallel computer

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

Faraj, Daniel A.

Determining collective barrier operation skew in a parallel computer that includes a number of compute nodes organized into an operational group includes: for each of the nodes until each node has been selected as a delayed node: selecting one of the nodes as a delayed node; entering, by each node other than the delayed node, a collective barrier operation; entering, after a delay by the delayed node, the collective barrier operation; receiving an exit signal from a root of the collective barrier operation; and measuring, for the delayed node, a barrier completion time. The barrier operation skew is calculated by:more » identifying, from the compute nodes' barrier completion times, a maximum barrier completion time and a minimum barrier completion time and calculating the barrier operation skew as the difference of the maximum and the minimum barrier completion time.« less

Transformation and speciation of typical heavy metals in soil aquifer treatment system during long time recharging with secondary effluent: Depth distribution and combination.

PubMed

Wei, Liangliang; Wang, Kun; Noguera, Daniel R; Jiang, Junqiu; Oyserman, Ben; Zhao, Ningbo; Zhao, Qingliang; Cui, Fuyi

2016-12-01

Soil aquifer treatment (SAT) systems rely on extensive physical and biogeochemical processes in the vadose zone and aquifer for water quality improvement. In this study, the distribution, quantitative changes, as well as the speciation characteristics of heavy metals in different depth of soils of a two-year operated lab-scale SAT was explored. A majority of the heavy metals in the recharged secondary effluent were efficiently trapped by the steady-state operated SAT (removal efficiency ranged from 74.7% to 98.2%). Thus, significant accumulations of 31.7% for Cd, 15.9% for Cu, 15.3% for Zn and 8.6% for Cr were observed for the top soil after 730 d operation, leading to the concentration (in μg g -1 ) of those four heavy metals of the packed soil increased from 0.51, 46.7, 61.0 and 35.7 to 0.66, 54.2, 70.4 and 38.8, respectively. By contrast, the accumulation of Mn and Pb were quite low. The residual species were the predominant fraction of the six heavy metals (ranged for 59.8-82.4%), followed by oxidisable species. Although the Zn, Cr, Cd, Cu and Mn were efficiently bounded onto the oxide components within the soil, the percentage of the labile metal fractions (water-, acid-exchangeable and reducible metal fractions) exhibited a slight increasing after 2 Y operation. Significantly heavy metals accumulation and slightly decreasing of the proportion of the stable fractions indicated a potentially higher environmental hazard for those six heavy metals after long-term SAT operation (especially for Cu, Zn and Cd). Finally, a linear relationship between the accumulation rate of metal species and the variation of soil organic carbon concentration and water extractable organic carbon was demonstrated. Copyright © 2016 Elsevier Ltd. All rights reserved.

Dating of 30m ice cores drilled by Japanese Antarctic Research Expedition and environmental change study

NASA Astrophysics Data System (ADS)

Motoyama, H.; Suzuki, T.; Fukui, K.; Ohno, H.; Hoshina, Y.; Hirabayashi, M.; Fujita, S.

2017-12-01

1. Introduction It is possible to reveal the past climate and environmental change from the ice core drilled in polar ice sheet and glaciers. The 54th Japanese Antarctic Research Expedition conducted several shallow core drillings up to 30 m depth in the inland and coastal areas of the East Antarctic ice sheet. Ice core sample was cut out at a thickness of about 5 cm in the cold room of the National Institute of Polar Research, and analyzed ion, water isotope, dust and so one. We also conducted dielectric profile measurement (DEP measurement). The age as a key layer of large-scale volcanic explosion was based on Sigl et al. (Nature Climate Change, 2014). 2. Inland ice core Ice cores were collected at the NDF site (77°47'14"S, 39°03'34"E, 3754 m.a.s.l.) and S80 site (80°00'00"S, 40°30'04"E, 3622 m.a.s.l.). Dating of ice core was done as follows. Calculate water equivalent from core density. Accumulate water equivalent from the surface. Approximate the relation of depth - cumulative water equivalent by a quartic equation. We determined the key layer with nssSO42 - peak corresponding to several large volcanic explosions. The accumulation rate was kept constant between the key layers. As a result, NDF was estimated to be around 1360 AD and S80 was estimated to be around 1400 AD in the deepest ice core. 3. Coastal ice core An ice core was collected at coastal H15 sites (69°04'10"S, 40°44'51"E, 1030 m.a.s.l.). Dating of ice core was done as follows. Calculate water equivalent from ice core density. Accumulate water equivalent from the surface. Approximate the relation of depth - cumulative water equivalent by a quartic equation. Basically we decided to summer (December) and winter (June) due to the seasonal change of the water isotope (δD or δ18O). In addition to the seasonal change of isotope, confirm the following. Maximum of SO42- / Na +, which is earlier in time than the maximum of water isotope. Maximum of MSA at about the same time as the maximum of the water isotope. Na+ is maximal immediately after the local maximum of the water isotope. The deepest age was estimated to be around 1940 AD. 4. Example of results In the inland area, the annual average surface mass balance decreased from 1450 to 1850 AD, but it has increased since 1850 AD. The annual mass balance of coastal H15 is consistent with the result of snow stake measurement.

Recognition of maximum flooding events in mixed siliciclastic-carbonate systems: Key to global chronostratigraphic correlation

USGS Publications Warehouse

Mancini, E.A.; Tew, B.H.

1997-01-01

The maximum flooding event within a depositional sequence is an important datum for correlation because it represents a virtually synchronous horizon. This event is typically recognized by a distinctive physical surface and/or a significant change in microfossil assemblages (relative fossil abundance peaks) in siliciclastic deposits from shoreline to continental slope environments in a passive margin setting. Recognition of maximum flooding events in mixed siliciclastic-carbonate sediments is more complicated because the entire section usually represents deposition in continental shelf environments with varying rates of biologic and carbonate productivity versus siliciclastic influx. Hence, this event cannot be consistently identified simply by relative fossil abundance peaks. Factors such as siliciclastic input, carbonate productivity, sediment accumulation rates, and paleoenvironmental conditions dramatically affect the relative abundances of microfossils. Failure to recognize these complications can lead to a sequence stratigraphic interpretation that substantially overestimates the number of depositional sequences of 1 to 10 m.y. duration.

Antarctic ice dynamics and southern ocean surface hydrology during the last glacial maximum

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

Labeyrie, L.D.; Burckle, L.; Labracherie, M.

1985-01-01

Eight high sedimentation rate cores located between 61/sup 0/S and 43/sup 0/S in the Atlantic and Indian sectors of the Southern Ocean have been studied in detail for foraminifera and diatom /sup 18/O//sup 16/O ratios, and changes in radiolarian and diatom specific abundance. Comparison of these different parameters permits a detailed description of the surface water hydrology during the last glacial maximum. The authors demonstrate that from 25 kyr BP to 15 kyr BP a large number of icebergs formed around the Antarctic continent. Melting along the Polar Front decreased surface salinity by approximately 1.5 per thousand between 43/sup 0/Smore » and 50/sup 0/S. They propose that an increase of snow accumulation at the Antarctic periphery and downdraw during maximum ice extension are primary causes for this major discharge of icebergs.« less

The adsorption kinetics of metal ions onto different microalgae and siliceous earth.

PubMed

Schmitt, D; Müller, A; Csögör, Z; Frimmel, F H; Posten, C

2001-03-01

In the present work the adsorption kinetics of the six metal ions aluminum, zinc, mercury, lead, copper, and cadmium onto living microalgae were measured. The freshwater green microalga Scenedesmus subspicatus, the brackish water diatom Cyclotella cryptica, the seawater diatom Phaeodactylum tricornutum, and the seawater red alga Porphyridium purpureum were the subject of investigation. In most cases the adsorption rate of the metals could be well described by using the equation of the Langmuir adsorption rate expression. Inverse parameter estimation allowed the determination of the rate constants of the adsorption process and the maximum metal content of the algae. The highest values for the rate constant were obtained for Porphyridium purpureum followed by Phaeodactylum tricornutum. High values for the maximum content were obtained for Cyclotella cryptica and Scenedesmus subspicatus. The maximum rate constant was 24.21 h-1 for the adsorption of Hg to Porphyridium purpureum whereas the maximum metal content (0.243 g g-1) was obtained for Zn on Cyclotella cryptica. A comparison of these values with those obtained for the mineral siliceous earth exhibiting low maximum content and high adsorption rates reveals that the mechanism of adsorption onto the algae is a mixture of adsorption and accumulation.

Health risk assessment of heavy metals in fish and accumulation patterns in food web in the upper Yangtze River, China.

PubMed

Yi, Yujun; Tang, Caihong; Yi, Tieci; Yang, Zhifeng; Zhang, Shanghong

2017-11-01

This study aims to concern the distribution of As, Cr, Cd, Hg, Cu, Zn, Pb and Fe in surface sediment, zoobenthos and fishes, and quantify the accumulative ecological risk and human health risk of metals in river ecological system based on the field investigation in the upper Yangtze River. The results revealed high ecological risk of As, Cd, Cu, Hg, Zn and Pb in sediment. As and Cd in fish presented potential human health risk of metals by assessing integrated target hazard quotient results based on average and maximum concentrations, respectively. No detrimental health effects of heavy metals on humans were found by daily fish consumption. While, the total target hazard quotient (1.659) exceeding 1, it meant that the exposed population might experience noncarcinogenic health risks from the accumulative effect of metals. Ecological network analysis model was established to identify the transfer routes and quantify accumulative effects of metals on river ecosystem. Control analysis between compartments showed large predator fish firstly depended on the omnivorous fish. Accumulative ecological risk of metals indicated that zoobenthos had the largest metal propagation risk and compartments located at higher trophic levels were not easier affected by the external environment pollution. A potential accumulative ecological risk of heavy metal in the food web was quantified, and the noncarcinogenic health risk of fish consumption was revealed for the upper reach of the Yangtze River. Copyright © 2017 Elsevier Inc. All rights reserved.

Accumulation of mercury in rice grain and cabbage grown on representative Chinese soils*

PubMed Central

Liu, Chun-fa; Wu, Cheng-xian; Rafiq, Muhammad T.; Aziz, Rukhsanda; Hou, Dan-di; Ding, Zhe-li; Lin, Zi-wen; Lou, Lin-jun; Feng, Yuan-yuan; Li, Ting-qiang; Yang, Xiao-e

2013-01-01

A pot culture experiment was carried out to investigate the accumulation properties of mercury (Hg) in rice grain and cabbage grown in seven soil types (Udic Ferrisols, Mollisol, Periudic Argosols, Latosol, Ustic Cambosols, Calcaric Regosols, and Stagnic Anthrosols) spiked with different concentrations of Hg (CK, 0.25, 0.50, 1.00, 2.00, and 4.00 mg/kg). The results of this study showed that Hg accumulation of plants was significantly affected by soil types. Hg concentration in both rice grain and cabbage increased with soil Hg concentrations, but this increase differed among the seven soils. The stepwise multiple regression analysis showed that pH, Mn(II), particle size distribution, and cation exchange capacity have a close relationship with Hg accumulation in plants, which suggested that physicochemical characteristics of soils can affect the Hg accumulation in rice grain and cabbage. Critical Hg concentrations in seven soils were identified for rice grain and cabbage based on the maximum safe level for daily intake of Hg, dietary habits of the population, and Hg accumulation in plants grown in different soil types. Soil Hg limits for rice grain in Udic Ferrisols, Mollisol, Periudic Argosols, Latosol, Ustic Cambosols, Calcaric Regosols, and Stagnic Anthrosols were 1.10, 2.00, 2.60, 2.78, 1.53, 0.63, and 2.17 mg/kg, respectively, and critical soil Hg levels for cabbage are 0.27, 1.35, 1.80, 1.70, 0.69, 1.68, and 2.60 mg/kg, respectively. PMID:24302714

Modeling the survivability of brucella to exposure of Ultraviolet radiation and temperature

NASA Astrophysics Data System (ADS)

Howe, R.

Accumulated summation of daily Ultra Violet-B (UV-B = 290? to 320 ? ) data? from The USDA Ultraviolet Radiation Monitoring Program show good correlation (R^2 = 77%) with daily temperature data during the five month period from February through June, 1998. Exposure of disease organisms, such as brucella to the effects of accumulated UV-B radiation, can be modeled for a 5 month period from February through June, 1998. Estimates of a lethal dosage for brucell of UV-B in the environment is dependent on minimum/maximum temperature and Solar Zenith Angle for the time period. The accumulated increase in temperature over this period also effects the decomposition of an aborted fetus containing brucella. Decomposition begins at some minimum daily temperature at 27 to 30 degrees C and peaks at 39 to 40C. It is useful to view the summation of temperature as a threshold for other bacteria growth, so that accumulated temperature greater than some value causes decomposition through competition with other bacteria and brucella die from the accumulated effects of UV-B, temperature and organism competition. Results of a study (Cook 1998) to determine survivability of brucellosis in the environment through exposure of aborted bovine fetuses show no one cause can be attributed to death of the disease agent. The combination of daily increase in temperature and accumulated UV-B radiation reveal an inverse correlation to survivability data and can be modeled as an indicator of brucella survivability in the environment in arid regions.

Spatio-temporal reconstruction of air temperature maps and their application to estimate rice growing season heat accumulation using multi-temporal MODIS data*

PubMed Central

Zhang, Li-wen; Huang, Jing-feng; Guo, Rui-fang; Li, Xin-xing; Sun, Wen-bo; Wang, Xiu-zhen

2013-01-01

The accumulation of thermal time usually represents the local heat resources to drive crop growth. Maps of temperature-based agro-meteorological indices are commonly generated by the spatial interpolation of data collected from meteorological stations with coarse geographic continuity. To solve the critical problems of estimating air temperature (T a) and filling in missing pixels due to cloudy and low-quality images in growing degree days (GDDs) calculation from remotely sensed data, a novel spatio-temporal algorithm for T a estimation from Terra and Aqua moderate resolution imaging spectroradiometer (MODIS) data was proposed. This is a preliminary study to calculate heat accumulation, expressed in accumulative growing degree days (AGDDs) above 10 °C, from reconstructed T a based on MODIS land surface temperature (LST) data. The verification results of maximum T a, minimum T a, GDD, and AGDD from MODIS-derived data to meteorological calculation were all satisfied with high correlations over 0.01 significant levels. Overall, MODIS-derived AGDD was slightly underestimated with almost 10% relative error. However, the feasibility of employing AGDD anomaly maps to characterize the 2001–2010 spatio-temporal variability of heat accumulation and estimating the 2011 heat accumulation distribution using only MODIS data was finally demonstrated in the current paper. Our study may supply a novel way to calculate AGDD in heat-related study concerning crop growth monitoring, agricultural climatic regionalization, and agro-meteorological disaster detection at the regional scale. PMID:23365013

Spatio-temporal reconstruction of air temperature maps and their application to estimate rice growing season heat accumulation using multi-temporal MODIS data.

PubMed

Zhang, Li-wen; Huang, Jing-feng; Guo, Rui-fang; Li, Xin-xing; Sun, Wen-bo; Wang, Xiu-zhen

2013-02-01

The accumulation of thermal time usually represents the local heat resources to drive crop growth. Maps of temperature-based agro-meteorological indices are commonly generated by the spatial interpolation of data collected from meteorological stations with coarse geographic continuity. To solve the critical problems of estimating air temperature (T(a)) and filling in missing pixels due to cloudy and low-quality images in growing degree days (GDDs) calculation from remotely sensed data, a novel spatio-temporal algorithm for T(a) estimation from Terra and Aqua moderate resolution imaging spectroradiometer (MODIS) data was proposed. This is a preliminary study to calculate heat accumulation, expressed in accumulative growing degree days (AGDDs) above 10 °C, from reconstructed T(a) based on MODIS land surface temperature (LST) data. The verification results of maximum T(a), minimum T(a), GDD, and AGDD from MODIS-derived data to meteorological calculation were all satisfied with high correlations over 0.01 significant levels. Overall, MODIS-derived AGDD was slightly underestimated with almost 10% relative error. However, the feasibility of employing AGDD anomaly maps to characterize the 2001-2010 spatio-temporal variability of heat accumulation and estimating the 2011 heat accumulation distribution using only MODIS data was finally demonstrated in the current paper. Our study may supply a novel way to calculate AGDD in heat-related study concerning crop growth monitoring, agricultural climatic regionalization, and agro-meteorological disaster detection at the regional scale.

The intrusion of engine exhaust into the passenger areas of recreational power boats

DOT National Transportation Integrated Search

1991-01-01

Tests were run to measure the concentrations of carbon monoxide that accumulate in the : passenger spaces of two recreational power boats during routine cruising operations. : Results indicate that during certain phases of operation, carbon monoxide ...

High-Frequency Testing of Composite Fan Vanes With Erosion-Resistant Coating Conducted

NASA Technical Reports Server (NTRS)

Bowman, Cheryl L.; Sutter, James K.; Naik, Subhash; Otten, Kim D.; Perusek, Gail P.

2003-01-01

The mechanical integrity of hard, erosion-resistant coatings were tested using the Structural Dynamics Laboratory at the NASA Glenn Research Center. Under the guidance of Structural Mechanics and Dynamics Branch personnel, fixturing and test procedures were developed at Glenn to simulate engine vibratory conditions on coated polymer-matrix- composite bypass vanes using a slip table in the Structural Dynamics Laboratory. Results from the high-frequency mechanical bench testing, along with concurrent erosion testing of coupons and vanes, provided sufficient confidence to engine-endurance test similarly coated vane segments. The knowledge gained from this program will be applied to the development of oxidation- and erosion-resistant coatings for polymer matrix composite blades and vanes in future advanced turbine engines. Fan bypass vanes from the AE3007 (Rolls Royce America, Indianapolis, IN) gas turbine engine were coated by Engelhard (Windsor, CT) with compliant bond coatings and hard ceramic coatings. The coatings were developed collaboratively by Glenn and Allison Advanced Development Corporation (AADC)/Rolls Royce America through research sponsored by the High-Temperature Engine Materials Technology Project (HITEMP) and the Higher Operating Temperature Propulsion Components (HOTPC) project. High-cycle fatigue was performed through high-frequency vibratory testing on a shaker table. Vane resonant frequency modes were surveyed from 50 to 3000 Hz at input loads from 1g to 55g on both uncoated production vanes and vanes with the erosion-resistant coating. Vanes were instrumented with both lightweight accelerometers and strain gauges to establish resonance, mode shape, and strain amplitudes. Two high-frequency dwell conditions were chosen to excite two strain levels: one approaching the vane's maximum allowable design strain and another near the expected maximum strain during engine operation. Six specimens were tested per dwell condition. Pretest and posttest inspections were performed optically at up to 60 magnification and using a fluorescent-dye penetrant. Accumulation of 10 million cycles at a strain amplitude of two to three times that expected in the engine (approximately 670 Hz and 20g) led to the development of multiple cracks in the coating that were only detectable using fluorescent-dye penetrant inspection. Cracks were prevalent on the trailing edge and on the convex side of the midsection. No cracking or spalling was evident using standard optical inspection at up to 60 magnification. Further inspection may reveal whether these fine cracks penetrated the coating or were strictly on the surface. The dwell condition that simulated actual engine conditions produced no obvious surface flaws even after up to 80 million cycles had been accumulated at strain amplitudes produced at approximately 1500 Hz and 45g.

Conference Digest LEOS Summer Topical Meetings 1992

DTIC Science & Technology

1992-12-09

of the circuit and determines the maximum frequency of operation. With...operating at a frequency of 335.48 MHz. The resultant timing jitter is determined by sending both pulse trains into a rotating mirror optical correlator with...length of 1.5 un and a gate width of 100 um. have a maximum transconductance of 160 mS/mm and a cut-off frequency of 10 GHz. To determine the

JPS heater and sensor lightning qualification

NASA Technical Reports Server (NTRS)

Cook, M.

1989-01-01

Simulated lightning strike testing of the Redesigned Solid Rocket Motor (RSRM) field joint protection system heater assembly was performed at Thiokol Corp., Wendover Lightning Facility. Testing consisted of subjecting the lightning evaluation test article to simulated lightning strikes and evaluating the effects of heater cable transients on cables within the systems tunnel. The maximum short circuit current coupled onto a United Space Boosters, Inc. operational flight cable within the systems tunnel, induced by transients from all cables external to the systems tunnel, was 92 amperes. The maximum open-circuit voltage coupled was 316 volts. The maximum short circuit current coupled onto a United Space Boosters, Inc. operational flight cable within the systems tunnel, induced by heater power cable transients only, was 2.7 amperes; the maximum open-circuit voltage coupled was 39 volts. All heater power cable induced coupling was due to simulated lightning discharges only, no heater operating power was applied during the test. The results showed that, for a worst-case lightning discharge, the heater power cable is responsible for a 3.9 decibel increase in voltage coupling to operational flight cables within the systems tunnel. Testing also showed that current and voltage levels coupled onto cables within the systems tunnel are partially dependant on the relative locations of the cables within the systems tunnel.

Intelligent energy harvesting scheme for microbial fuel cells: Maximum power point tracking and voltage overshoot avoidance

NASA Astrophysics Data System (ADS)

Alaraj, Muhannad; Radenkovic, Miloje; Park, Jae-Do

2017-02-01

Microbial fuel cells (MFCs) are renewable and sustainable energy sources that can be used for various applications. The MFC output power depends on its biochemical conditions as well as the terminal operating points in terms of output voltage and current. There exists one operating point that gives the maximum possible power from the MFC, maximum power point (MPP), for a given operating condition. However, this MPP may vary and needs to be tracked in order to maintain the maximum power extraction from the MFC. Furthermore, MFC reactors often develop voltage overshoots that cause drastic drops in the terminal voltage, current, and the output power. When the voltage overshoot happens, an additional control measure is necessary as conventional MPPT algorithms will fail because of the change in the voltage-current relationship. In this paper, the extremum seeking (ES) algorithm was used to track the varying MPP and a voltage overshoot avoidance (VOA) algorithm is developed to manage the voltage overshoot conditions. The proposed ES-MPPT with VOA algorithm was able to extract 197.2 mJ during 10-min operation avoiding voltage overshoot, while the ES MPPT-only scheme stopped harvesting after only 18.75 mJ because of the voltage overshoot happened at 0.4 min.

Extending the maximum operation time of the MNSR reactor.

PubMed

Dawahra, S; Khattab, K; Saba, G

2016-09-01

An effective modification to extend the maximum operation time of the Miniature Neutron Source Reactor (MNSR) to enhance the utilization of the reactor has been tested using the MCNP4C code. This modification consisted of inserting manually in each of the reactor inner irradiation tube a chain of three polyethylene-connected containers filled of water. The total height of the chain was 11.5cm. The replacement of the actual cadmium absorber with B(10) absorber was needed as well. The rest of the core structure materials and dimensions remained unchanged. A 3-D neutronic model with the new modifications was developed to compare the neutronic parameters of the old and modified cores. The results of the old and modified core excess reactivities (ρex) were: 3.954, 6.241 mk respectively. The maximum reactor operation times were: 428, 1025min and the safety reactivity factors were: 1.654 and 1.595 respectively. Therefore, a 139% increase in the maximum reactor operation time was noticed for the modified core. This increase enhanced the utilization of the MNSR reactor to conduct a long time irradiation of the unknown samples using the NAA technique and increase the amount of radioisotope production in the reactor. Copyright © 2016 Elsevier Ltd. All rights reserved.

Maximum home blood pressure is a useful indicator of diabetic nephropathy in patients with type 2 diabetes mellitus: KAMOGAWA-HBP study.

PubMed

Oyabu, Chikako; Ushigome, Emi; Matsumoto, Shinobu; Tanaka, Toru; Hasegawa, Goji; Nakamura, Naoto; Ohnishi, Masayoshi; Tsunoda, Sei; Ushigome, Hidetaka; Yokota, Isao; Tanaka, Muhei; Asano, Mai; Yamazaki, Masahiro; Fukui, Michiaki

2017-11-01

Maximum home systolic blood pressure has been shown to predict target organ damage. We aimed to clarify the association between maximum home systolic blood pressure and urine albumin to creatinine ratio, an indicator of early-phase diabetic nephropathy in patients with type 2 diabetes. In 1040 patients, we assessed the relationship of mean or maximum home systolic blood pressure and urine albumin to creatinine ratio, and compared the area under the receiver operating characteristic curve of mean or maximum home systolic blood pressure for diabetic nephropathy (urine albumin to creatinine ratio ⩾30 mg/g Cr). Multivariate linear regression analyses indicated that mean morning systolic blood pressure ( β = 0.010, p < 0.001) and maximum morning systolic blood pressure ( β = 0.008, p < 0.001) were significantly associated with urine albumin to creatinine ratio. Area under the receiver operating characteristic curve (95% confidence interval) for diabetic nephropathy in mean and maximum morning systolic blood pressure was 0.667 (0.634-0.700; p < 0.001) and 0.671 (0.638-0.703; p < 0.001), respectively. Maximum home systolic blood pressure, as well as mean home systolic blood pressure, was significantly associated with diabetic nephropathy in patients with type 2 diabetes.

33 CFR Appendix A to Part 154 - Guidelines for Detonation Flame Arresters

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CG-522). 1. Scope 1.1This standard provides the minimum requirements for design, construction.../Circ. 373/Rev. 1—Revised Standards for the Design, Testing and Locating of Devices to Prevent the... maximum design pressure drop for that maximum flow rate. 6.1.10Maximum operating pressure. 7. Materials 7...

40 CFR 147.1803 - Existing Class I and III wells authorized by rule-maximum injection pressure.

Code of Federal Regulations, 2010 CFR

2010-07-01

... authorized by rule-maximum injection pressure. 147.1803 Section 147.1803 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) STATE, TRIBAL, AND EPA-ADMINISTERED...—maximum injection pressure. The owner or operator shall limit injection pressure to the lesser of: (a) A...

Screening of native plants and algae growing on fly-ash affected areas near National Thermal Power Corporation, Tanda, Uttar Pradesh, India for accumulation of toxic heavy metals.

PubMed

Dwivedi, S; Srivastava, S; Mishra, S; Dixit, B; Kumar, A; Tripathi, R D

2008-10-30

The present investigation was carried out to screen native plants growing in fly-ash (FA) contaminated areas near National Thermal Power Corporation, Tanda, Uttar Pradesh, India with a view to using them for the eco-restoration of the area. A total number of 17 plants (9 aquatic, 6 terrestrial and 2 algal species) were collected and screened for heavy metal (Fe, Zn, Cu, Mo, B, Si, Al, Cr, Pb, Cd, Hg and As) accumulation. Differential accumulation of various heavy metals by different species of plants was observed. Hydrilla verticillata was found to be the most efficient metal accumulator among 9 aquatic plants, Eclipta alba among 6 terrestrial plants and Phormedium papyraceum between 2 algal species. In general, the maximum levels of most metals were found in terrestrial plants while the lowest in algal species. However, translocation of the metals from root to shoot was found to be higher in aquatic plants than terrestrial ones. These results suggest that various aquatic, terrestrial and algal species of plants may be used in a synergistic way to remediate and restore the FA contaminated areas.

Optimizing phytoremediation of heavy metal-contaminated soil by exploiting plants' stress adaptation.

PubMed

Barocsi, Attila; Csintalan, Zsolt; Kocsanyi, Laszlo; Dushenkov, Slavik; Kuperberg, J Michael; Kucharski, Rafal; Richter, Peter I

2003-01-01

Soil phytoextraction is based on the ability of plants to extract contaminants from the soil. For less bioavailable metals, such as Pb, a chelator is added to the soil to mobilize the metal. The effect can be significant and in certain species, heavy metal accumulation can rapidly increase 10-fold. Accumulation of high levels of toxic metals may result in irreversible damage to the plant. Monitoring and controlling the phytotoxicity caused by EDTA-induced metal accumulation is crucial to optimize the remedial process, i.e. to achieve maximum uptake. We describe an EDTA-application procedure that minimizes phytotoxicity by increasing plant tolerance and allows phytoextraction of elevated levels of Pb and Cd. Brassica juncea is tested in soil with typical Pb and Cd concentrations of 500 mg kg-1 and 15 mg kg-1, respectively. Instead of a single dose treatment, the chelator is applied in multiple doses, that is, in several small increments, thus providing time for plants to initiate their adaptation mechanisms and raise their damage threshold. In situ monitoring of plant stress conditions by chlorophyll fluorescence recording allows for the identification of the saturating heavy metal accumulation process and of simultaneous plant deterioration.

Enhanced lipid accumulation of green microalga Scenedesmus sp. by metal ions and EDTA addition.

PubMed

Ren, Hong-Yu; Liu, Bing-Feng; Kong, Fanying; Zhao, Lei; Xie, Guo-Jun; Ren, Nan-Qi

2014-10-01

Effects of Fe(3+) (0-0.12 g/L), Mg(2+) (0-0.73 g/L) and Ca(2+) (0-0.98 g/L) on the biomass and lipid accumulation of heterotrophic microalgae were investigated in dark environment. The biomass and lipid production exhibited an increasing trend with increasing the concentrations of metal ions. In cultures with 1.2 × 10(-3) g/L Fe(3+), 7.3 × 10(-3) g/L Mg(2+) and 9.8 × 10(-4) g/L Ca(2+), the maximum biomass, total lipid content and lipid productivity reached 3.49 g/L, 47.4% and 275.7 mg/L/d, respectively. More importantly, EDTA addition (1.0 × 10(-3) g/L) could enhance the solubility of metal ions (iron and calcium) and increase their availability by microalgae, which evidently promote the lipid accumulation. Compared with the control, the total lipid content and lipid productivity increased 28.2% and 29.7%, respectively. These show that appropriate concentrations of metal ions and EDTA in the culture medium were beneficial to lipid accumulation of heterotrophic Scenedesmus sp. cells. Copyright © 2014 Elsevier Ltd. All rights reserved.

Surface origin and control of resonance Raman scattering and surface band gap in indium nitride

NASA Astrophysics Data System (ADS)

Alarcón-Lladó, Esther; Brazzini, Tommaso; Ager, Joel W.

2016-06-01

Resonance Raman scattering measurements were performed on indium nitride thin films under conditions where the surface electron concentration was controlled by an electrolyte gate. As the surface condition is tuned from electron depletion to accumulation, the spectral feature at the expected position of the (E 1, A 1) longitudinal optical (LO) near 590 cm-1 shifts to lower frequency. The shift is reversibly controlled with the applied gate potential, which clearly demonstrates the surface origin of this feature. The result is interpreted within the framework of a Martin double resonance, where the surface functions as a planar defect, allowing the scattering of long wavevector phonons. The allowed wavevector range, and hence the frequency, is modulated by the electron accumulation due to band gap narrowing. A surface band gap reduction of over 500 meV is estimated for the conditions of maximum electron accumulation. Under conditions of electron depletion, the full InN bandgap (E g  =  0.65 eV) is expected at the surface. The drastic change in the surface band gap is expected to influence the transport properties of devices which utilize the surface electron accumulation layer.

Vertical distribution of 137Cs in alluvial soils of the Lokna River floodplain (Tula oblast) long after the Chernobyl accident and its simulation

NASA Astrophysics Data System (ADS)

Mamikhin, S. V.; Golosov, V. N.; Paramonova, T. A.; Shamshurina, E. N.; Ivanov, M. M.

2016-12-01

Profiles of vertical 137Cs distribution in alluvial meadow soils on the low and medium levels of the Lokna River floodplain (central part of the Plavsk radioactive spot in Tula oblast) 28 years after the Chernobyl fallout have been studied. A significant increase in the 137Cs pool is revealed on the low floodplain areas compared to the soils of interfluves due to the accumulation of alluvium, which hampers the reduction of the total radionuclide pool in alluvial soils because of radioactive decay. The rate of alluvium accumulation in the soil on the medium floodplain level is lower by three times on average. An imitation prognostic model has been developed, which considers the flooding and climatic conditions in the region under study. Numerical experiments have quantitatively confirmed the deciding role of low-mobile forms in the migration of maximum 137Cs content along the soil profile in the absence of manifested erosion-accumulation processes.

Bioremoval of trace metals from rhizosediment by mangrove plants in Indian Sundarban Wetland.

PubMed

Chowdhury, Ranju; Favas, Paulo J C; Jonathan, M P; Venkatachalam, Perumal; Raja, P; Sarkar, Santosh Kumar

2017-11-30

The study accentuated the trace metal accumulation and distribution pattern in individual organs of 13 native mangrove plants along with rhizosediments in the Indian Sundarban Wetland. Enrichment of the essential micronutrients (Mn, Fe, Zn, Cu, Co, Ni) was recorded in all plant organs in comparison to non-essential ones, such as Cr, As, Pb, Cd, Hg. Trunk bark and root/pneumatophore showed maximum metal accumulation efficiency. Rhizosediment recorded manifold increase for most of the trace metals than plant tissue, with the following descending order: Fe>Mn>Zn>Cu>Pb>Ni>Cr>Co>As>Cd>Hg. Concentrations of Cu, Ni, Pb and Hg were found to exceed prescribed sediment quality guidelines (SQGs) indicating adverse effect on adjacent biota. Both index of geoaccumulation (I geo ) and enrichment factor (EF) also indicated anthropogenic contamination. Based on high (>1) translocation factor (TF) and bioconcentration factor (BCF) values Sonneratiaapetala and Avicenniaofficinalis could be considered as potential accumulators, of trace metals. Copyright © 2017 Elsevier Ltd. All rights reserved.

Tumour-on-a-chip provides an optical window into nanoparticle tissue transport

NASA Astrophysics Data System (ADS)

Albanese, Alexandre; Lam, Alan K.; Sykes, Edward A.; Rocheleau, Jonathan V.; Chan, Warren C. W.

2013-10-01

Nanomaterials are used for numerous biomedical applications, but the selection of optimal properties for maximum delivery remains challenging. Thus, there is a significant interest in elucidating the nano-bio interactions underlying tissue accumulation. To date, researchers have relied on cell culture or animal models to study nano-bio interactions. However, cell cultures lack the complexity of biological tissues and animal models are prohibitively slow and expensive. Here we report a tumour-on-a-chip system where incorporation of tumour-like spheroids into a microfluidic channel permits real-time analysis of nanoparticle (NP) accumulation at physiological flow conditions. We show that penetration of NPs into the tissue is limited by their diameter and that retention can be improved by receptor targeting. NP transport is predominantly diffusion-limited with convection improving accumulation mostly at the tissue perimeter. A murine tumour model confirms these findings and demonstrates that the tumour-on-a-chip can be useful for screening optimal NP designs prior to in vivo studies.

SAFEGUARDS REPORT FOR THE NORTHROP PULSE RADIATION FACILITY

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

Feinauer, E.; Thomas, R.D.

1961-03-22

Ae description is given of the Northrop pulse Radiation Facility, (NPRF), which consists of a TRlGA Mark-F reactor and associated supporting equipment. The NPRF was designed to operate in the following modes: Mode 1-100 kw steady-state operation; Mode II--Pulsed operation up to a maximum transient giving a maximum measured fuel element temperature of 470 deg C, which corresponds to an energy release of about 18 Mw-sec (approximately 1.9% sigma K/ K). The movable reactor will be operated in three general areas in the pool: adjacent to the exposure room; adjacent to the beam ponts; or at intermediate positions. Based onmore » the analyses presented and operating experience with the prototype TRIGA Mark F and other TRlGA reactors, it is concluded that operation of the NPRF does not present any undue hazard to the health and safety of the operating personnel or the public. (auth)« less

46 CFR 151.04-1 - Certificate of inspection.

Code of Federal Regulations, 2011 CFR

2011-10-01

... CARRYING BULK LIQUID HAZARDOUS MATERIAL CARGOES Inspection and Certification § 151.04-1 Certificate of... maximum cargo weight (short tons), maximum density (pounds per gallon) and any operating limitations and a...

46 CFR 151.04-1 - Certificate of inspection.

Code of Federal Regulations, 2010 CFR

2010-10-01

... CARRYING BULK LIQUID HAZARDOUS MATERIAL CARGOES Inspection and Certification § 151.04-1 Certificate of... maximum cargo weight (short tons), maximum density (pounds per gallon) and any operating limitations and a...

Interactions between calcium precipitation and the polyphosphate-accumulating bacteria metabolism.

PubMed

Barat, R; Montoya, T; Borrás, L; Ferrer, J; Seco, A

2008-07-01

A sequencing batch reactor that is operated for biological phosphorus removal has been operated under different influent calcium concentrations to study the precipitation process and the possible effects of phosphorus precipitation in the biological phosphorus removal process. Four experiments were carried out under different influent calcium concentrations ranging from 10 to 90 g Ca m(-3). The experimental results and the equilibrium study, which are based on the saturation index calculation, confirm that the process controlling the calcium behaviour is the calcium phosphate precipitation. This precipitation takes place at two stages: initially, precipitation of the amorphous calcium phosphate, and later crystallization of hydroxyapatite. Also the accumulation of phosphorus precipitated was observed when the influent calcium concentration was increased. In all the experiments, the influent wastewater ratio P/COD was kept constant. It has been observed that, at high calcium concentration, the ratio between phosphate release and acetate uptake (P(rel)/Ac(uptake)) decreases. Changes in the polyphosphate-accumulating organism (PAO) population and in the glycogen-accumulating organism (GAO) population during the experimental period were ruled out by means of fluorescence in situ hybridization. These results could suggest that PAO are able to change their metabolic pathways based on external conditions, such as influent calcium concentration. The accumulation of phosphorus precipitated as calcium phosphate at high influent calcium concentration throughout the experimental period confirmed that phosphate precipitation is a process that can affect the PAO metabolism.

Operator's manual on the visual-accumulation tube method for sedimentation analysis of sands

USGS Publications Warehouse

Colby, V.C.; Witzgman, F.W.

1958-01-01

The personnel who will be operating these units may have little or no previous knowledge of either the principles involved or the details of opera.ting procedure. This manual is intended as an aid to them in setting up the apparatus, learning the analytical procedure, interpreting the results, and understanding the primary principles encountered.

Crassulacean acid metabolism, CO2-recycling, and tissue desiccation in the Mexican epiphyte Tillandsia schiedeana Steud (Bromeliaceae).

PubMed

Martin, C E; Adams, W W

1987-01-01

After 23 days without water in a greenhouse, rates of nocturnal CO2 uptake in Tillandsia schiedeana decreased substantially and maximum rates occurred later in the dark period eventually coinciding with the onset of illumination. Nocturnal CO2 uptake accounted for less than half the total nighttime increase in acidity measured in well-watered plants. With increased tissue desiccation, only 11-12% of measured acid accumulation was attributable to atmospheric CO2 uptake. Plants desiccated for 30 days regained initial levels of nocturnal acid accumulation and CO2 uptake after rehydration for 10h. These results stress the importance of CO2 recycling via CAM in this epiphytic bromeliad, especially during droughts.

[Effect of suspended silt from dredging at Yangtze estuary on Brachionus plicatilis].

PubMed

Wang, Jinqui; Xu, Zhaoli; Shi, Chun; Chen, Yaqu

2002-07-01

The effect of suspended silt from dredging at Yangtze estuary on Brachionus plicatilis was investigated by clonal culture (to construct life table) and population accumulative culture. The intrinsic increasing rate of the rotifer population was greatly reduced under different concentrations (1, 3, 5, 7 and 9 mg.ml-1) of silt, from 29.6% to 64.1%, and to a maximum of 130.0%. The suspended silt affected population survival rate, rather than its reproduction rate. In accumulative culture, the densities of female, males, parthenogenetic eggs, and resting eggs in the population were not affected by silt. It was concluded that the presence of suspended silt should have a certain negative influence on the rotifer population in dredging Yangtze estuary.

Microbial production of polyhydroxybutyrate with tailor-made properties: an integrated modelling approach and experimental validation.

PubMed

Penloglou, Giannis; Chatzidoukas, Christos; Kiparissides, Costas

2012-01-01

The microbial production of polyhydroxybutyrate (PHB) is a complex process in which the final quantity and quality of the PHB depend on a large number of process operating variables. Consequently, the design and optimal dynamic operation of a microbial process for the efficient production of PHB with tailor-made molecular properties is an extremely interesting problem. The present study investigates how key process operating variables (i.e., nutritional and aeration conditions) affect the biomass production rate and the PHB accumulation in the cells and its associated molecular weight distribution. A combined metabolic/polymerization/macroscopic modelling approach, relating the process performance and product quality with the process variables, was developed and validated using an extensive series of experiments and measurements. The model predicts the dynamic evolution of the biomass growth, the polymer accumulation, the consumption of carbon and nitrogen sources and the average molecular weights of the PHB in a bioreactor, under batch and fed-batch operating conditions. The proposed integrated model was used for the model-based optimization of the production of PHB with tailor-made molecular properties in Azohydromonas lata bacteria. The process optimization led to a high intracellular PHB accumulation (up to 95% g of PHB per g of DCW) and the production of different grades (i.e., different molecular weight distributions) of PHB. Copyright © 2011 Elsevier Inc. All rights reserved.

Afterslip behavior following the M6.0, 2014 South Napa earthquake with implications for afterslip forecasting on other seismogenic faults

USGS Publications Warehouse

Lienkaemper, James J.; DeLong, Stephen B.; Domrose, Carolyn J; Rosa, Carla M.

2016-01-01

The M6.0, 24 Aug. 2014 South Napa, California, earthquake exhibited unusually large slip for a California strike-slip event of its size with a maximum coseismic surface slip of 40-50 cm in the north section of the 15 km-long rupture. Although only minor (<10 cm) surface slip occurred coseismically in the southern 9-km section of the rupture, there was considerable postseismic slip, so that the maximum total slip one year after the event approached 40-50 cm, about equal to the coseismic maximum in the north. We measured the accumulation of postseismic surface slip on four, ~100-m-long alignment arrays for one year following the event. Because prolonged afterslip can delay reconstruction of fault-damaged buildings and infrastructure, we analyzed its gradual decay to estimate when significant afterslip would likely end. This forecasting of Napa afterslip suggests how we might approach the scientific and engineering challenges of afterslip from a much larger M~7 earthquake anticipated on the nearby, urban Hayward Fault. However, we expect its afterslip to last much longer than one year.The M6.0, 24 Aug. 2014 South Napa, California, earthquake exhibited unusually large slip for a California strike-slip event of its size with a maximum coseismic surface slip of 40-50 cm in the north section of the 15 km-long rupture. Although only minor (<10 cm) surface slip occurred coseismically in the southern 9-km section of the rupture, there was considerable postseismic slip, so that the maximum total slip one year after the event approached 40-50 cm, about equal to the coseismic maximum in the north. We measured the accumulation of postseismic surface slip on four, ~100-m-long alignment arrays for one year following the event. Because prolonged afterslip can delay reconstruction of fault-damaged buildings and infrastructure, we analyzed its gradual decay to estimate when significant afterslip would likely end. This forecasting of Napa afterslip suggests how we might approach the scientific and engineering challenges of afterslip from a much larger M~7 earthquake anticipated on the nearby, urban Hayward Fault. However, we expect its afterslip to last much longer than one year.

Association of Lipid Accumulation Product with Cardio-Metabolic Risk Factors in Postmenopausal Women.

PubMed

Namazi Shabestari, Alireza; Asadi, Mojgan; Jouyandeh, Zahra; Qorbani, Mostafa; Kelishadi, Roya

2016-06-01

The lipid accumulation product is a novel, safe and inexpensive index of central lipid over accumulation based on waist circumference and fasting concentration of circulating triglycerides. This study was designed to investigate the ability of lipid accumulation product to predict Cardio-metabolic risk factors in postmenopausal women. In this Cross-sectional study, 264 postmenopausal women by using convenience sampling method were selected from menopause clinic in Tehran. Cardio-metabolic risk factors were measured, and lipid accumulation product (waist-58×triglycerides [nmol/L]) was calculated. Optimal cut-off point of lipid accumulation product for predicting metabolic syndrome was estimated by ROC (Receiver-operating characteristic) curve analysis. Metabolic syndrome was diagnosed in 41.2% of subjects. Optimal cut-off point of lipid accumulation product for predicting metabolic syndrome was 47.63 (sensitivity:75%; specificity:77.9%). High lipid accumulation product increases risk of all Cardio-metabolic risk factors except overweight, high Total Cholesterol, high Low Density Lipoprotein Cholesterol and high Fasting Blood Sugar in postmenopausal women. Our findings show that lipid accumulation product is associated with metabolic syndrome and some Cardio-metabolic risk factors Also lipid accumulation product may have been a useful tool for predicting cardiovascular disease and metabolic syndrome risk in postmenopausal women.

Forecasting the remaining reservoir capacity in the Laurentian Great Lakes watershed

NASA Astrophysics Data System (ADS)

Alighalehbabakhani, Fatemeh; Miller, Carol J.; Baskaran, Mark; Selegean, James P.; Barkach, John H.; Dahl, Travis; Abkenar, Seyed Mohsen Sadatiyan

2017-12-01

Sediment accumulation behind a dam is a significant factor in reservoir operation and watershed management. There are many dams located within the Laurentian Great Lakes watershed whose operations have been adversely affected by excessive reservoir sedimentation. Reservoir sedimentation effects include reduction of flood control capability and limitations to both water supply withdrawals and power generation due to reduced reservoir storage. In this research, the sediment accumulation rates of twelve reservoirs within the Great Lakes watershed were evaluated using the Soil and Water Assessment Tool (SWAT). The estimated sediment accumulation rates by SWAT were compared to estimates relying on radionuclide dating of sediment cores and bathymetric survey methods. Based on the sediment accumulation rate, the remaining reservoir capacity for each study site was estimated. Evaluation of the anthropogenic impacts including land use change and dam construction on the sediment yield were assessed in this research. The regression analysis was done on the current and pre-European settlement sediment yield for the modeled watersheds to predict the current and natural sediment yield in un-modeled watersheds. These eleven watersheds are in the state of Indiana, Michigan, Ohio, New York, and Wisconsin.

Feller/bunchers in plantations thinnings: factors affecting productivity.

Treesearch

Sharon A. Winsauer; James A. Mattson; Michael A. Thompson

1984-01-01

Computer simulation was used to identify possible areas for improving the design and operation of feller/bunchers for thinning closely spaced plantations. Some of the variables considered were average stand diameter, tree spacing, thinning pattern, operational machine speeds, and shear head accumulating capacity.

On-orbit operations and offline data processing of CALET onboard the ISS

NASA Astrophysics Data System (ADS)

Asaoka, Y.; Ozawa, S.; Torii, S.; Adriani, O.; Akaike, Y.; Asano, K.; Bagliesi, M. G.; Bigongiari, G.; Binns, W. R.; Bonechi, S.; Bongi, M.; Brogi, P.; Buckley, J. H.; Cannady, N.; Castellini, G.; Checchia, C.; Cherry, M. L.; Collazuol, G.; Di Felice, V.; Ebisawa, K.; Fuke, H.; Guzik, T. G.; Hams, T.; Hareyama, M.; Hasebe, N.; Hibino, K.; Ichimura, M.; Ioka, K.; Ishizaki, W.; Israel, M. H.; Javaid, A.; Kasahara, K.; Kataoka, J.; Kataoka, R.; Katayose, Y.; Kato, C.; Kawanaka, N.; Kawakubo, Y.; Krawczynski, H. S.; Krizmanic, J. F.; Kuramata, S.; Lomtadze, T.; Maestro, P.; Marrocchesi, P. S.; Messineo, A. M.; Mitchell, J. W.; Miyake, S.; Mizutani, K.; Moiseev, A. A.; Mori, K.; Mori, M.; Mori, N.; Motz, H. M.; Munakata, K.; Murakami, H.; Nakahira, S.; Nishimura, J.; de Nolfo, G. A.; Okuno, S.; Ormes, J. F.; Pacini, L.; Palma, F.; Papini, P.; Penacchioni, A. V.; Rauch, B. F.; Ricciarini, S. B.; Sakai, K.; Sakamoto, T.; Sasaki, M.; Shimizu, Y.; Shiomi, A.; Sparvoli, R.; Spillantini, P.; Stolzi, F.; Takahashi, I.; Takayanagi, M.; Takita, M.; Tamura, T.; Tateyama, N.; Terasawa, T.; Tomida, H.; Tsunesada, Y.; Uchihori, Y.; Ueno, S.; Vannuccini, E.; Wefel, J. P.; Yamaoka, K.; Yanagita, S.; Yoshida, A.; Yoshida, K.; Yuda, T.

2018-07-01

The CALorimetric Electron Telescope (CALET), launched for installation on the International Space Station (ISS) in August, 2015, has been accumulating scientific data since October, 2015. CALET is intended to perform long-duration observations of high-energy cosmic rays onboard the ISS. CALET directly measures the cosmic-ray electron spectrum in the energy range of 1 GeV to 20 TeV with a 2% energy resolution above 30 GeV. In addition, the instrument can measure the spectrum of gamma rays well into the TeV range, and the spectra of protons and nuclei up to a PeV. In order to operate the CALET onboard ISS, JAXA Ground Support Equipment (JAXA-GSE) and the Waseda CALET Operations Center (WCOC) have been established at JAXA and Waseda University, respectively. Scientific operations using CALET are planned at WCOC, taking into account orbital variations of geomagnetic rigidity cutoff. Scheduled command sequences are used to control the CALET observation modes on orbit. Calibration data acquisition by, for example, recording pedestal and penetrating particle events, a low-energy electron trigger mode operating at high geomagnetic latitude, a low-energy gamma-ray trigger mode operating at low geomagnetic latitude, and an ultra heavy trigger mode, are scheduled around the ISS orbit while maintaining maximum exposure to high-energy electrons and other high-energy shower events by always having the high-energy trigger mode active. The WCOC also prepares and distributes CALET flight data to collaborators in Italy and the United States. As of August 31, 2017, the total observation time is 689 days with a live time fraction of the total time of ∼ 84%. Nearly 450 million events are collected with a high-energy (E > 10 GeV) trigger. In addition, calibration data acquisition and low-energy trigger modes, as well as an ultra-heavy trigger mode, are consistently scheduled around the ISS orbit. By combining all operation modes with the excellent-quality on-orbit data collected thus far, it is expected that a five-year observation period will provide a wealth of new and interesting results.

Law of damage accumulation and fracture criteria in highly filled polymer materials

NASA Astrophysics Data System (ADS)

Bykov, D. L.; Kazakov, A. V.; Konovalov, D. N.; Mel'nikov, V. P.; Milyokhin, Yu. M.; Peleshko, V. A.; Sadovnichii, D. N.

2014-09-01

We present the results of a large series of experiments aimed at the study of laws of damage accumulation and fracture in highly filled polymer materials under loading conditions of various types: monotone, repeated, low- and high-cycle, with varying type of stress state, dynamic (in general, more than 50 programs implemented on specimens from one lot of material). The data obtained in these test allow one to make conclusions about the constitutive role of the attained maximum of strain intensity when estimating the accumulated damage in the process of uniaxial tension by various programs (in particular, an additional cyclic deformation below the preliminary attained strain maximum does not affect the limit values of strain and stress in the subsequent active extension), about the strong influence of the stress state on the deformation and fracture, about the specific features of the nonlinear behavior of the material under the shock loading conditions and its influence on the repeated deformation. All tests are described (with an accuracy acceptable in practical calculations, both with respect to stresses and strains in the process of loading and at the moment of fracture) in the framework of the same model of nonlinear viscoelasticity with the same set of constants. The constants of the proposed model are calculated according to a relatively simple algorithm by using the results of standard uniaxial tension tests with constant values of the strain rate and hydrostatic pressure (each test for 2-3 levels of these parameters chosen from the ranges proposed in applications, each loading lasts until the fracture occurs, and one of the tests contains an intermediate interval of total loading and repeated loading) and one axial shock compression test if there are dynamic problems in the applications. The model is based on the use of the criterion fracture parameter which, in the class of proportional loading processes, is the sum of partial increments of the strain intensity on active segments of the process (where the strain intensity is at its historical maximum) with the form of the stress state and the intensity of strain rates taken into account.

Diode-pumped continuous-wave and passively Q-switched Nd:GdLuAG laser at 1443.9 nm

NASA Astrophysics Data System (ADS)

Wu, Qianwen; Liu, Zhaojun; Zhang, Sasa; Cong, Zhenghua; Guan, Chen; Xue, Feng; Chen, Hui; Huang, Qingjie; Xu, Xiaodong; Xu, Jun; Qin, Zengguang

2017-12-01

We investigated the 1443.9 nm laser characteristics of Nd:GdLuAG crystal. Diode-end-pumping configuration was employed under both continuous-wave (CW) and passively Q-switched operations. For CW operation, the maximum average output power was 1.36 W with a slope efficiency of 15%. By using a V3+:YAG crystal as the saturable absorber, we obtained the maximum average output power of 164 mW under Q-switched operation. The corresponding pulse energy was 29.3 μJ and pulse duration was 59 ns.

Accumulation of humic-like and proteinaceous dissolved organic matter in zero-discharge aquaculture systems as revealed by fluorescence EEM spectroscopy.

PubMed

Yamin, G; Borisover, M; Cohen, E; van Rijn, J

2017-01-01

Recirculating aquaculture systems (RAS), offering many economic and fish husbandry benefits, are characterized by an accumulation of dissolved organic matter (DOM) and, specifically, humic substances (HS). As reported in a number of studies, HS may affect biological activity in both invertebrates and vertebrates. Given the accumulation of HS in RAS, it is therefore of great interest to characterize DOM and, specifically, its HS fraction in the RAS. The present study was aimed at characterizing long-term changes in fluorescent DOM composition in the culture water of RAS systems, which were operated in a novel, zero water exchange mode. Two such zero-discharge recirculating systems (ZDS) were examined: a freshwater system, stocked with hybrid tilapia (Oreochromis aureus x Oreochromis niloticus) and a marine system, stocked with gilthead seabream (Sparus aurata). Excitation-emission matrices (EEMs) of fluorescence, coupled with parallel factor analysis (PARAFAC), were used to characterize and quantify the different DOM components in the ZDS. In the culture water, one tryptophan-like and four HS-like components were identified. The fluorescence intensities of three of the HS-like components as well as the tryptophan-like component increased at comparable rates during ZDS operation while a much slower accumulation of these compounds was observed in a parallel operated, flow-through, freshwater aquarium. The ZDS examined in this study comprised a sludge digestion stage where a considerable accumulation of all fluorescent components was detected. A HS-like components and a tryptophan-like component in blood of tilapia from the freshwater ZDS were similar to components found in the culture water. Blood levels of both components were higher in fish cultured in the DOM-rich ZDS than in fish raised in the control, flow-through freshwater aquarium. Fluorescence of the HS-like component found in the fish blood increased also with time of ZDS operation. The finding that fish blood contains a HS-like fluorescent component may have important implications for the understanding of the physiological effects of HS in fish and the possible benefits of these substances in aquaculture. Copyright © 2016 Elsevier Ltd. All rights reserved.

14 CFR 93.129 - Additional operations.

Code of Federal Regulations, 2010 CFR

2010-01-01

...) AIR TRAFFIC AND GENERAL OPERATING RULES SPECIAL AIR TRAFFIC RULES High Density Traffic Airports § 93... under IFR at a designated high density traffic airport without regard to the maximum number of operations allocated for that airport if the operation is not a scheduled operation to or from a high density...

14 CFR 23.1507 - Operating maneuvering speed.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Operating maneuvering speed. 23.1507... Limitations and Information § 23.1507 Operating maneuvering speed. The maximum operating maneuvering speed, VO, must be established as an operating limitation. VO is a selected speed that is not greater than VS√n...

14 CFR 23.1507 - Operating maneuvering speed.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Operating maneuvering speed. 23.1507... Limitations and Information § 23.1507 Operating maneuvering speed. The maximum operating maneuvering speed, VO, must be established as an operating limitation. VO is a selected speed that is not greater than VS√n...

14 CFR 93.129 - Additional operations.

Code of Federal Regulations, 2014 CFR

2014-01-01

...) AIR TRAFFIC AND GENERAL OPERATING RULES SPECIAL AIR TRAFFIC RULES High Density Traffic Airports § 93... under IFR at a designated high density traffic airport without regard to the maximum number of operations allocated for that airport if the operation is not a scheduled operation to or from a high density...

14 CFR 93.129 - Additional operations.

Code of Federal Regulations, 2013 CFR

2013-01-01

...) AIR TRAFFIC AND GENERAL OPERATING RULES SPECIAL AIR TRAFFIC RULES High Density Traffic Airports § 93... under IFR at a designated high density traffic airport without regard to the maximum number of operations allocated for that airport if the operation is not a scheduled operation to or from a high density...

14 CFR 93.129 - Additional operations.

Code of Federal Regulations, 2011 CFR

2011-01-01

...) AIR TRAFFIC AND GENERAL OPERATING RULES SPECIAL AIR TRAFFIC RULES High Density Traffic Airports § 93... under IFR at a designated high density traffic airport without regard to the maximum number of operations allocated for that airport if the operation is not a scheduled operation to or from a high density...

14 CFR 93.129 - Additional operations.

Code of Federal Regulations, 2012 CFR

2012-01-01

...) AIR TRAFFIC AND GENERAL OPERATING RULES SPECIAL AIR TRAFFIC RULES High Density Traffic Airports § 93... under IFR at a designated high density traffic airport without regard to the maximum number of operations allocated for that airport if the operation is not a scheduled operation to or from a high density...

Cable Bundle Wire Derating

NASA Technical Reports Server (NTRS)

Lundquist, Ray A.; Leidecker, Henning

1998-01-01

The allowable operating currents of electrical wiring when used in the space vacuum environment is predominantly determined by the maximum operating temperature of the wire insulation. For Kapton insulated wire this value is 200 C. Guidelines provided in the Goddard Space Flight Center (GSFC) Preferred Parts List (PPL) limit the operating current of wire within vacuum to ensure the maximum insulation temperature is not exceeded. For 20 AWG wire, these operating parameters are: 3.7 amps per wire, bundle of 15 or more wires, 70 C environment, and vacuum of 10(exp -5) torr or less. To determine the behavior and temperature of electrical wire at different operating conditions, a thermal vacuum test was performed on a representative electrical harness of the Hubble Space Telescope (HST) power distribution system. This paper describes the test and the results.

Atmospheric Radiation Measurement program climate research facility operations quarterly report July 1 - Sep. 30, 2009.

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

Sisterson, D. L.

2009-10-15

Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near-real time. Raw and processed data are then sent approximately daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and monthmore » for the current year and (2) site and fiscal year (FY) dating back to 1998. The U.S. Department of Energy (DOE) requires national user facilities to report time-based operating data. The requirements concern the actual hours of operation (ACTUAL); the estimated maximum operation or uptime goal (OPSMAX), which accounts for planned downtime; and the VARIANCE [1 - (ACTUAL/OPSMAX)], which accounts for unplanned downtime. The OPSMAX time for the fourth quarter of FY 2009 for the Southern Great Plains (SGP) site is 2,097.60 hours (0.95 ? 2,208 hours this quarter). The OPSMAX for the North Slope Alaska (NSA) locale is 1,987.20 hours (0.90 ? 2,208) and for the Tropical Western Pacific (TWP) locale is 1,876.8 hours (0.85 ? 2,208). The ARM Mobile Facility (AMF) was officially operational May 1 in Graciosa Island, the Azores, Portugal, so the OPSMAX time this quarter is 2,097.60 hours (0.95 x 2,208). The differences in OPSMAX performance reflect the complexity of local logistics and the frequency of extreme weather events. It is impractical to measure OPSMAX for each instrument or data stream. Data availability reported here refers to the average of the individual, continuous data streams that have been received by the Archive. Data not at the Archive result from downtime (scheduled or unplanned) of the individual instruments. Therefore, data availability is directly related to individual instrument uptime. Thus, the average percentage of data in the Archive represents the average percentage of the time (24 hours per day, 92 days for this quarter) the instruments were operating this quarter. Table 1 shows the accumulated maximum operation time (planned uptime), actual hours of operation, and variance (unplanned downtime) for the period July 1 - September 30, 2009, for the fixed sites. Because the AMF operates episodically, the AMF statistics are reported separately and not included in the aggregate average with the fixed sites. The fourth quarter comprises a total of 2,208 hours for the fixed and mobile sites. The average of the fixed sites well exceeded our goal this quarter. The AMF data statistic requires explanation. Since the AMF radar data ingest software is being modified, the data are being stored in the DMF for data processing. Hence, the data are not at the Archive; they are anticipated to become available by the next report.« less

Analysis and prediction of operating vehicle load effects on Highway bridges under the weight charge policy

NASA Astrophysics Data System (ADS)

Huang, Haiyun; Zhang, Junping; Li, Yonghe

2018-05-01

Under the weight charge policy, the weigh in motion data at a toll station on the Jing-Zhu Expressway were collected. The statistic analysis of vehicle load data was carried out. For calculating the operating vehicle load effects on bridges, by Monte Carlo method used to generate random traffic flow and influence line loading method, the maximum bending moment effect of simple supported beams were obtained. The extreme value I distribution and normal distribution were used to simulate the distribution of the maximum bending moment effect. By the extrapolation of Rice formula and the extreme value I distribution, the predicted values of the maximum load effects were obtained. By comparing with vehicle load effect according to current specification, some references were provided for the management of the operating vehicles and the revision of the bridge specifications.

Optimization Research on Ampacity of Underground High Voltage Cable Based on Interior Point Method

NASA Astrophysics Data System (ADS)

Huang, Feng; Li, Jing

2017-12-01

The conservative operation method which takes unified current-carrying capacity as maximum load current can’t make full use of the overall power transmission capacity of the cable. It’s not the optimal operation state for the cable cluster. In order to improve the transmission capacity of underground cables in cluster, this paper regards the maximum overall load current as the objective function and the temperature of any cables lower than maximum permissible temperature as constraint condition. The interior point method which is very effective for nonlinear problem is put forward to solve the extreme value of the problem and determine the optimal operating current of each loop. The results show that the optimal solutions obtained with the purposed method is able to increase the total load current about 5%. It greatly improves the economic performance of the cable cluster.

Determination of the wind power systems load to achieve operation in the maximum energy area

NASA Astrophysics Data System (ADS)

Chioncel, C. P.; Tirian, G. O.; Spunei, E.; Gillich, N.

2018-01-01

This paper analyses the operation of the wind turbine, WT, in the maximum power point, MPP, by linking the load of the Permanent Magnet Synchronous Generator, PMSG, with the wind speed value. The load control methods at wind power systems aiming an optimum performance in terms of energy are based on the fact that the energy captured by the wind turbine significantly depends on the mechanical angular speed of the wind turbine. The presented control method consists in determining the optimal mechanical angular speed, ωOPTIM, using an auxiliary low power wind turbine, WTAUX, operating without load, at maximum angular velocity, ωMAX. The method relies on the fact that the ratio ωOPTIM/ωMAX has a constant value for a given wind turbine and does not depend on the time variation of the wind speed values.

Similar mid-depth Atlantic water mass provenance during the Last Glacial Maximum and Heinrich Stadial 1

NASA Astrophysics Data System (ADS)

Howe, Jacob N. W.; Huang, Kuo-Fang; Oppo, Delia W.; Chiessi, Cristiano M.; Mulitza, Stefan; Blusztajn, Jurek; Piotrowski, Alexander M.

2018-05-01

The delivery of freshwater to the North Atlantic during Heinrich Stadial 1 (HS1) is thought to have fundamentally altered the operation of Atlantic meridional overturning circulation (AMOC). Although benthic foraminiferal carbon isotope records from the mid-depth Atlantic show a pronounced excursion to lower values during HS1, whether these shifts correspond to changes in water mass proportions, advection, or shifts in the carbon cycle remains unclear. Here we present new deglacial records of authigenic neodymium isotopes - a water mass tracer that is independent of the carbon cycle - from two cores in the mid-depth South Atlantic. We find no change in neodymium isotopic composition, and thus water mass proportions, between the Last Glacial Maximum (LGM) and HS1, despite large decreases in carbon isotope values at the onset of HS1 in the same cores. We suggest that the excursions of carbon isotopes to lower values were likely caused by the accumulation of respired organic matter due to slow overturning circulation, rather than to increased southern-sourced water, as typically assumed. The finding that there was little change in water mass provenance in the mid-depth South Atlantic between the LGM and HS1, despite decreased overturning, suggests that the rate of production of mid-depth southern-sourced water mass decreased in concert with decreased production of northern-sourced intermediate water at the onset of HS1. Consequently, we propose that even drastic changes in the strength of AMOC need not cause a significant change in South Atlantic mid-depth water mass proportions.

49 CFR 398.6 - Hours of service of drivers; maximum driving time.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 5 2011-10-01 2011-10-01 false Hours of service of drivers; maximum driving time... REGULATIONS TRANSPORTATION OF MIGRANT WORKERS § 398.6 Hours of service of drivers; maximum driving time. No... or operate for more than 10 hours in the aggregate (excluding rest stops and stops for meals) in any...

49 CFR 398.6 - Hours of service of drivers; maximum driving time.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 5 2010-10-01 2010-10-01 false Hours of service of drivers; maximum driving time... REGULATIONS TRANSPORTATION OF MIGRANT WORKERS § 398.6 Hours of service of drivers; maximum driving time. No... or operate for more than 10 hours in the aggregate (excluding rest stops and stops for meals) in any...

77 FR 40092 - License Amendment To Increase the Maximum Reactor Power Level, Florida Power & Light Company, St...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-06

... Increase the Maximum Reactor Power Level, Florida Power & Light Company, St. Lucie, Units 1 and 2 AGENCY... amendment for Renewed Facility Operating License Nos. DPR-67 and NPF-16, issued to Florida Power & Light... St. Lucie County, Florida. The proposed license amendment would increase the maximum thermal power...

Temperature initiated passive cooling system

DOEpatents

Forsberg, Charles W.

1994-01-01

A passive cooling system for cooling an enclosure only when the enclosure temperature exceeds a maximum standby temperature comprises a passive heat transfer loop containing heat transfer fluid having a particular thermodynamic critical point temperature just above the maximum standby temperature. An upper portion of the heat transfer loop is insulated to prevent two phase operation below the maximum standby temperature.

An analysis of collegiate band directors' exposure to sound pressure levels

NASA Astrophysics Data System (ADS)

Roebuck, Nikole Moore

Noise-induced hearing loss (NIHL) is a significant but unfortunate common occupational hazard. The purpose of the current study was to measure the magnitude of sound pressure levels generated within a collegiate band room and determine if those sound pressure levels are of a magnitude that exceeds the policy standards and recommendations of the Occupational Safety and Health Administration (OSHA), and the National Institute of Occupational Safety and Health (NIOSH). In addition, reverberation times were measured and analyzed in order to determine the appropriateness of acoustical conditions for the band rehearsal environment. Sound pressure measurements were taken from the rehearsal of seven collegiate marching bands. Single sample t test were conducted to compare the sound pressure levels of all bands to the noise exposure standards of OSHA and NIOSH. Multiple regression analysis were conducted and analyzed in order to determine the effect of the band room's conditions on the sound pressure levels and reverberation times. Time weighted averages (TWA), noise percentage doses, and peak levels were also collected. The mean Leq for all band directors was 90.5 dBA. The total accumulated noise percentage dose for all band directors was 77.6% of the maximum allowable daily noise dose under the OSHA standard. The total calculated TWA for all band directors was 88.2% of the maximum allowable daily noise dose under the OSHA standard. The total accumulated noise percentage dose for all band directors was 152.1% of the maximum allowable daily noise dose under the NIOSH standards, and the total calculated TWA for all band directors was 93dBA of the maximum allowable daily noise dose under the NIOSH standard. Multiple regression analysis revealed that the room volume, the level of acoustical treatment and the mean room reverberation time predicted 80% of the variance in sound pressure levels in this study.

Climate-vegetation-fire interactions and their impact on long-term carbon dynamics in a boreal peatland landscape in northern Manitoba, Canada

NASA Astrophysics Data System (ADS)

Camill, Philip; Barry, Ann; Williams, Evie; Andreassi, Christian; Limmer, Jacob; Solick, Donald

2009-12-01

Climate warming may increase the size and frequency of fires in the boreal biome, possibly causing greater carbon release that amplifies warming. However, in peatlands, vegetation change may also control long-term fire and carbon accumulation, confounding simple relationships between climate, fire, and carbon accumulation. Using 17 peat cores dating to 8000 cal years B.P. from northern Manitoba, Canada, we addressed the following questions: (1) Do past climate changes correlate with shifts in peatland vegetation? (2) What is the relationship between peatland vegetation and fire severity? (3) What is the mean return interval for boreal peat fires, and how does it change across fires of different severities? (4) How does fire severity affect carbon accumulation rates? (5) Do fire and long-term carbon accumulation change directly in response to climate or indirectly though climate-driven changes in vegetation? We measured carbon accumulation rates, fire severity, and return intervals using macroscopic charcoal and changes in vegetation using macrofossils. Climate and vegetation changes covaried, with shifts from wetter fen to drier, forested bog communities during the Holocene Thermal Maximum (HTM). Fires became more severe following the shift to forested bogs, with fire severity peaking after 4000 cal years B.P. rather than during the HTM. Rising fire severity, in turn, was correlated with a significant decrease in carbon accumulation from ˜6000 to 2000 cal years B.P. The Medieval Warm Period and Little Ice Age affected vegetation composition and permafrost, further impacting fire and carbon accumulation. Our results indicate that long-term changes in fire and carbon dynamics are mediated by climate-driven changes in vegetation.

Ultraviolet irradiation induces accumulation of isoflavonoids and transcription of genes of enzymes involved in the calycosin-7-O-β-d-glucoside pathway in Astragalus membranaceus Bge. var. mongholicus (Bge.) Hsiao.

PubMed

Xu, Rong-Yan; Nan, Peng; Yang, Yixin; Pan, Haiyun; Zhou, Tongshui; Chen, Jiakuan

2011-07-01

Isoflavonoids are a group of phenolic secondary metabolites found almost exclusively in leguminous plants. Formononetin, calycosin and calycosin-7-O-β-d-glucoside (CG) are isoflavonoid products in the CG pathway. Accumulation of the three isoflavonoids plus daidzein and expression of six genes of enzymes involved in the CG pathway were studied in Astragalus membranaceus Bge. var. mongholicus (Bge.) Hsiao with ultraviolet (UV) irradiation. Our results showed that (1) main isoflavonoids in roots, stems and leaves were CG, daidzein and calycosin, respectively; they accumulated significantly under the induction of UV irradiation during 8 days but their content declined later; (2) expression of six genes of enzymes involved in the CG pathway was inhibited slightly at early stage but the expression was increased greatly afterward; (3) chalcone synthase, chalcone reductase and chalcone isomerase were expressed to their individual maximum level within shorter hours than were cinnamate 4-hydroxylase, isoflavone synthase (IFS) and isoflavone 3'-hydroxylase and (4) more calycosin but less daidzein accumulated in leaves. IFS was highly expressed in leaves, which might lead to high accumulation of the common precursor of daidzein and 2,7-dihydroxy-4'-O-methoxy-isoflavanone, the latter of which would be converted to formononetin, calycosin and CG via a series of reactions. Little daidzein accumulated in leaves, which suggested that rather than be converted to daidzein, the 2,7,4'-trihydroxyisoflavanone was probably more easily caught by 2-hydroxyisoflavanone 4'-O-methyltransferase and hence provided more precursors for formononetin. The findings were discussed in terms of the influence of UV irradiation in the accumulation of isoflavonoids. Copyright © Physiologia Plantarum 2011.

Abscisic Acid Accumulation in Spinach Leaf Slices in the Presence of Penetrating and Nonpenetrating Solutes 1

PubMed Central

Creelman, Robert A.; Zeevaart, Jan A. D.

1985-01-01

Abscisic acid (ABA) accumulated in detached, wilted leaves of spinach (Spinacia oleracea L. cv Savoy Hybrid 612) and reached a maximum level within 3 to 4 hours. The increase in ABA over that found in detached turgid leaves was approximately 10-fold. The effects of water stress could be mimicked by the use of thin slices of spinach leaves incubated in the presence of 0.6 molar mannitol, a compound which causes plasmolysis (loss of turgor). About equal amounts of ABA were found both in the leaf slices and in detached leaves, whereas 2 to 4 times more ABA accumulated in the medium than in the slices. When spinach leaf slices were incubated with ethylene glycol, a compound which rapidly penetrates the cell membrane causing a decrease in the osmotic potential of the tissue and only transient loss of turgor, no ABA accumulated. Ethylene glycol was not inhibitory with respect to ABA accumulation. Spinach leaf slices incubated in both ethylene glycol and mannitol had ABA levels similar to those found when slices were incubated with mannitol alone. Increases similar to those found with mannitol also occurred when Aquacide III, a highly purified form of polyethylene glycol, was used. Aquacide III causes cytorrhysis, a situation similar to that found in wilted leaves. Thus, it appears that loss of turgor is essential for ABA accumulation. When spinach leaf slices were incubated with solutes which are supposed to disturb membrane integrity (KHSO3, 2-propanol, or KCl) no increase in ABA was observed. These data indicate that, with respect to the accumulation of ABA, mannitol caused a physical stress (loss of turgor) rather than a chemical stress (membrane damage). PMID:16664022

Abscisic Acid accumulation in spinach leaf slices in the presence of penetrating and nonpenetrating solutes.

PubMed

Creelman, R A; Zeevaart, J A

1985-01-01

Abscisic acid (ABA) accumulated in detached, wilted leaves of spinach (Spinacia oleracea L. cv Savoy Hybrid 612) and reached a maximum level within 3 to 4 hours. The increase in ABA over that found in detached turgid leaves was approximately 10-fold. The effects of water stress could be mimicked by the use of thin slices of spinach leaves incubated in the presence of 0.6 molar mannitol, a compound which causes plasmolysis (loss of turgor). About equal amounts of ABA were found both in the leaf slices and in detached leaves, whereas 2 to 4 times more ABA accumulated in the medium than in the slices. When spinach leaf slices were incubated with ethylene glycol, a compound which rapidly penetrates the cell membrane causing a decrease in the osmotic potential of the tissue and only transient loss of turgor, no ABA accumulated. Ethylene glycol was not inhibitory with respect to ABA accumulation. Spinach leaf slices incubated in both ethylene glycol and mannitol had ABA levels similar to those found when slices were incubated with mannitol alone. Increases similar to those found with mannitol also occurred when Aquacide III, a highly purified form of polyethylene glycol, was used. Aquacide III causes cytorrhysis, a situation similar to that found in wilted leaves. Thus, it appears that loss of turgor is essential for ABA accumulation.When spinach leaf slices were incubated with solutes which are supposed to disturb membrane integrity (KHSO(3), 2-propanol, or KCl) no increase in ABA was observed. These data indicate that, with respect to the accumulation of ABA, mannitol caused a physical stress (loss of turgor) rather than a chemical stress (membrane damage).

Lifetime improvement mechanism in organic light-emitting diodes with mixed materials at a heterojunction interface

NASA Astrophysics Data System (ADS)

Minagawa, Masahiro; Takahashi, Noriko

2016-02-01

To investigate the lifetime improvement mechanism caused by mixing at the heterojunction interface, organic light-emitting diodes (OLEDs) with stacked and mixed 4,4‧-bis[N-(1-naphthyl)-N-phenyl-amino]-biphenyl (α-NPD)/tris(8-hydroxyquinoline)aluminum (Alq3) interfaces were fabricated, and changes in their displacement current due to continuous operation were measured. A decrease in accumulated holes at the α-NPD/Alq3 interface was observed in the stacked configuration devices over longer operations. These results indicate that the injected hole density was reduced during continuous operation, implying that the carrier balance became uneven in the emission region. However, few accumulated holes and changes in the displacement current due to continuous operation were observed in the devices having the mixed layer. Therefore, it was deduced that the number of holes concentrated between the α-NPD and Alq3 layers was decreased by mixing at the heterojunction interface, and that the change in the number of holes was smaller during continuous operation, resulting in less degradation.

Continuous operation of thermophilic food waste digestion with side-stream ammonia stripping.

PubMed

Zhang, Wei; Heaven, Sonia; Banks, Charles J

2017-11-01

Digesters fed on food waste (high nitrogen content) were operated successfully over an extended period using sidestream biogas stripping to control total ammonia nitrogen (TAN) below inhibitory concentrations. This is the first time biogas stripping has been used to achieve stable thermophilic operation with undiluted substrate of this type. Stripping columns operated batch-wise treated the equivalent of 1.7-4.1% of digester contents daily at pH >10 and 70°C, with no detrimental effect on digestion. TKN removal was 54%, with potential to recover 3.5kgNtonne -1 substrate. When stripping was stopped in one digester TAN increased, accompanied by rising propionic acid concentrations with progressive instability observed from 2.5gNL -1 . Eventual failure as TAN approached 5gNL -1 was due to rapid acetic acid accumulation, resulting in a fall in pH to below 6.5. The pattern of VFA accumulation indicated failure of both acetoclastic methanogenesis and acetate oxidation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Maximum Achievable Control Technology Standards in Region 7

EPA Pesticide Factsheets

Maximum Achievable Control Technology Standards (MACTs) are applicable requirements under the Title V operating permit program. This is a resource for permit writers and reviewers to learn about the rules and explore other helpful tools.

Accumulation by fish of contaminants released from dredged sediments

USGS Publications Warehouse

Seelye, James G.; Hesselberg, Robert J.; Mac, Michael J.

1982-01-01

Inasmuch as the process of dredging and disposing of dredged materials causes a resuspension of these materials and an increase in bioavailability of associated contaminants, we conducted a series of experiments to examine the potential accumulation by fish of contaminants from suspended sediments. In the first experiment we compared accumulation of contaminants by yellow perch of hatchery and lake origin and found that after 10 days of exposure to nonaerated sediments, fish of hatchery origin accumulated PCBs and Fe, while fish of lake origin accumulated As, Cr, Fe, and Na. Two additional exposures were conducted to evaluate the effects of aerating the sediments prior to measuring bioavailability of associated contaminants. Fish of hatchery origin exposed to nonaerated sediments for 10 days accumulated PCBs and Hg, while fish of hatchery origin exposed to aerated sediments for 10 days accumulated PCBs, DDE, Zn, Fe, Cs, and Se. These results demonstrated not only the potential for uptake of contaminants by fish as a result of dredging but also the potential utility of fish bioassays in evaluating proposed dredging operations.

Thermodynamic analysis of energy density in pressure retarded osmosis: The impact of solution volumes and costs

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

Reimund, Kevin K.; McCutcheon, Jeffrey R.; Wilson, Aaron D.

A general method was developed for estimating the volumetric energy efficiency of pressure retarded osmosis via pressure-volume analysis of a membrane process. The resulting model requires only the osmotic pressure, π, and mass fraction, w, of water in the concentrated and dilute feed solutions to estimate the maximum achievable specific energy density, uu, as a function of operating pressure. The model is independent of any membrane or module properties. This method utilizes equilibrium analysis to specify the volumetric mixing fraction of concentrated and dilute solution as a function of operating pressure, and provides results for the total volumetric energy densitymore » of similar order to more complex models for the mixing of seawater and riverwater. Within the framework of this analysis, the total volumetric energy density is maximized, for an idealized case, when the operating pressure is π/(1+√w⁻¹), which is lower than the maximum power density operating pressure, Δπ/2, derived elsewhere, and is a function of the solute osmotic pressure at a given mass fraction. It was also found that a minimum 1.45 kmol of ideal solute is required to produce 1 kWh of energy while a system operating at “maximum power density operating pressure” requires at least 2.9 kmol. Utilizing this methodology, it is possible to examine the effects of volumetric solution cost, operation of a module at various pressure, and operation of a constant pressure module with various feed.« less

Coordinated Freeway and Arterial Operations Handbook

DOT National Transportation Integrated Search

2006-05-01

Managing and operating freeways and adjacent arterials in a proactive and comprehensive manner, from a system user's perspective, is a major step toward operating all modes of the transportation system at maximum efficiency. The focus of this guide i...

LEOS 1992 - Summer Topical Meeting Digest Held in Santa Barbara, California on July 29-12 August, 1992

DTIC Science & Technology

1992-01-01

careful design of the device to maximise the relaxation oscillation resonance frequency [2], minimize leakage currents [2,3], and optimize other...and determines the maximum frequency of operation. With hybrid circuit construction this maximum frequency would generally be in the order of a few...operating at a frequency of 335.48 MHz. The resultant timing jitter is determined by sending both pulse trains into a rotating mirror optical