Methods and apparatus for handling or treating particulate material
NASA Technical Reports Server (NTRS)
Littman, Howard (Inventor); Plawsky, Joel L. (Inventor); Paccione, John D. (Inventor)
2009-01-01
An improved draft tube spout fluid bed (DTSFB) mixing, handling, conveying, and treating apparatus and systems, and methods for operating are provided. The apparatus and systems can accept particulate material and pneumatically or hydraulically conveying the material to mix and/or treat the material. In addition to conveying apparatus, a collection and separation apparatus adapted to receive the conveyed particulate material is also provided. The collection apparatus may include an impaction plate against which the conveyed material is directed to improve mixing and/or treatment. The improved apparatus are characterized by means of controlling the operation of the pneumatic or hydraulic transfer to enhance the mixing and/or reacting by controlling the flow of fluids, for example, air, into and out of the apparatus. The disclosed apparatus may be used to mix particulate material, for example, mortar; react fluids with particulate material; coat particulate material, or simply convey particulate material.
Electrically heated particulate filter enhanced ignition strategy
Gonze, Eugene V; Paratore, Jr., Michael J
2012-10-23
An exhaust system that processes exhaust generated by an engine is provided. The system generally includes a particulate filter (PF) that filters particulates from the exhaust wherein an upstream end of the PF receives exhaust from the engine. A grid of electrically resistive material is applied to an exterior upstream surface of the PF and selectively heats exhaust passing through the grid to initiate combustion of particulates within the PF. A catalyst coating applied to at least one of the PF and the grid. A control module estimates a temperature of the grid and controls the engine to produce a desired exhaust product to increase the temperature of the grid.
ERIC Educational Resources Information Center
Ozmen, Haluk
2011-01-01
In this study, the effect of animation enhanced conceptual change texts (CCT-CA) on grade 6 students' understanding of the particulate nature of matter (PNM) and transformation during the phase changes was investigated. A quasi-experimental design and one control group (CG, N = 25) and one experimental group (EG, N = 26) were used. While the…
Waste Water Treatment Apparatus and Methods
NASA Technical Reports Server (NTRS)
Plawsky, Joel L. (Inventor); Paccione, John D. (Inventor); Littman, Howard (Inventor)
2014-01-01
An improved draft tube spout fluid bed (DTSFB) mixing, handling, conveying, and treating apparatus and systems, and methods for operating are provided. The apparatus and systems can accept particulate material and pneumatically or hydraulically conveying the material to mix and/or treat the material. In addition to conveying apparatus, a collection and separation apparatus adapted to receive the conveyed particulate material is also provided. The collection apparatus may include an impaction plate against which the conveyed material is directed to improve mixing and/or treatment. The improved apparatus are characterized by means of controlling the operation of the pneumatic or hydraulic transfer to enhance the mixing and/or reacting by controlling the flow of fluids, for example, air, into and out of the apparatus. The disclosed apparatus may be used to mix particulate material, for example, mortar; react fluids with particulate material; coat particulate material, or simply convey particulate material.
Aslan, Kadir; Malyn, Stuart N.; Zhang, Yongxia; Geddes, Chris D.
2008-01-01
We report the effects of thermally annealing, non-, just-, and thick continuous silver films for their potential applications in metal-enhanced fluorescence, a near-field concept which can alter the free-space absorption and emissive properties of close-proximity fluorophores (excited states). We have chosen to anneal a noncontinuous particulate film 5 nm thick and two thicker continuous films, 15 and 25 nm thick, respectively. Our results show that the annealing of the 25 nm film has little effect on close-proximity fluorescence when coated with a monolayer of fluorophore-labeled protein. However, the 15 nm continuous film cracks upon annealing, producing large nanoparticles which are ideal for enhancing the fluorescence of close-proximity fluorophores that are indeed difficult to prepare by other wet-chemical deposition processes. The annealing of 5 nm noncontinuous particulate films (a control sample) has little influence on metal-enhanced fluorescence, as expected. PMID:19479004
Aslan, Kadir; Malyn, Stuart N; Zhang, Yongxia; Geddes, Chris D
2008-04-15
We report the effects of thermally annealing, non-, just-, and thick continuous silver films for their potential applications in metal-enhanced fluorescence, a near-field concept which can alter the free-space absorption and emissive properties of close-proximity fluorophores (excited states). We have chosen to anneal a noncontinuous particulate film 5 nm thick and two thicker continuous films, 15 and 25 nm thick, respectively. Our results show that the annealing of the 25 nm film has little effect on close-proximity fluorescence when coated with a monolayer of fluorophore-labeled protein. However, the 15 nm continuous film cracks upon annealing, producing large nanoparticles which are ideal for enhancing the fluorescence of close-proximity fluorophores that are indeed difficult to prepare by other wet-chemical deposition processes. The annealing of 5 nm noncontinuous particulate films (a control sample) has little influence on metal-enhanced fluorescence, as expected.
Storey, John Morse; Curran, Scott J.; Lewis, Samuel A.; ...
2016-08-04
Low-temperature compression ignition combustion can result in nearly smokeless combustion, as indicated by a smoke meter or other forms of soot measurement that rely on absorbance due to elemental carbon content. Highly premixed low-temperature combustion modes do not form particulate matter in the traditional pathways seen with conventional diesel combustion. Previous research into reactivity controlled compression ignition particulate matter has shown, despite a near zero smoke number, significant mass can be collected on filter media used for particulate matter certification measurement. In addition, particulate matter size distributions reveal that a fraction of the particles survive heated double-dilution conditions. This papermore » summarizes research completed at Oak Ridge National Laboratory to date on characterizing the nature, chemistry and aftertreatment considerations of reactivity controlled compression ignition particulate matter and presents new research highlighting the importance of injection strategy and fuel composition on reactivity controlled compression ignition particulate matter formation. Particle size measurements and the transmission electron microscopy results do show the presence of soot particles; however, the elemental carbon fraction was, in many cases, within the uncertainty of the thermal–optical measurement. Particulate matter emitted during reactivity controlled compression ignition operation was also collected with a novel sampling technique and analyzed by thermal desorption or pyrolysis gas chromatography mass spectroscopy. Particulate matter speciation results indicated that the high boiling range of diesel hydrocarbons was likely responsible for the particulate matter mass captured on the filter media. Finally, to investigate potential fuel chemistry effects, either ethanol or biodiesel were incorporated to assess whether oxygenated fuels may enhance particle emission reduction.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Storey, John Morse; Curran, Scott J.; Lewis, Samuel A.
Low-temperature compression ignition combustion can result in nearly smokeless combustion, as indicated by a smoke meter or other forms of soot measurement that rely on absorbance due to elemental carbon content. Highly premixed low-temperature combustion modes do not form particulate matter in the traditional pathways seen with conventional diesel combustion. Previous research into reactivity controlled compression ignition particulate matter has shown, despite a near zero smoke number, significant mass can be collected on filter media used for particulate matter certification measurement. In addition, particulate matter size distributions reveal that a fraction of the particles survive heated double-dilution conditions. This papermore » summarizes research completed at Oak Ridge National Laboratory to date on characterizing the nature, chemistry and aftertreatment considerations of reactivity controlled compression ignition particulate matter and presents new research highlighting the importance of injection strategy and fuel composition on reactivity controlled compression ignition particulate matter formation. Particle size measurements and the transmission electron microscopy results do show the presence of soot particles; however, the elemental carbon fraction was, in many cases, within the uncertainty of the thermal–optical measurement. Particulate matter emitted during reactivity controlled compression ignition operation was also collected with a novel sampling technique and analyzed by thermal desorption or pyrolysis gas chromatography mass spectroscopy. Particulate matter speciation results indicated that the high boiling range of diesel hydrocarbons was likely responsible for the particulate matter mass captured on the filter media. Finally, to investigate potential fuel chemistry effects, either ethanol or biodiesel were incorporated to assess whether oxygenated fuels may enhance particle emission reduction.« less
Gaikwad, Dinanath; Shewale, Rajnita; Patil, Vinit; Mali, Dipak; Gaikwad, Uday; Jadhav, Namdeo
2017-11-01
The aim of this work was to prepare pectin-poly (vinyl pyrrolidone) [PVP] based curcumin particulates to enhance the anticancer potential of curcumin, solubility and allow its localized controlled release. Pectin-PVP based curcumin particulates (PECTIN-PVP CUR) were prepared by spray drying technique in different ratios and were evaluated for surface morphology, micromeritics, flowability, particle size, drug content, in vitro dissolution, inhalable fraction, anti-angiogenesis/angiolysis and cytotoxicity. Results of micromeritic properties, Carr's index, Hausner's ratio and angle of repose were satisfactory. The batch CP3 was considered as optimum, due to excellent flowability, acceptable aggregation and enhanced solubility. The particle size and size distribution data of selected batch CP3 showed 90% of curcumin particulates having size less than 2.74μm, which may deposit to lungs. Twin Impinger studies showed that 29% of respirable fraction was generated, which could be directly delivered to lungs. The in vitro dissolution data showed many fold increase in dissolution rate. Angiolytic activity and MTT assay of PECTIN-PVP CUR have demonstrated enhancement in the anti-tumor potential, compared to curcumin alone. Altogether, PECTIN-PVP CUR were found suitable for local delivery and enhance its anticancer potential of curcumin. Copyright © 2017 Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Christoffersen, S.W.; Rouse, G.T.; Krasnopoler, M.J.
1998-07-01
The Dickerson Generating Station evaluated several particulate control options to identify the most cost-effective option. The study's goals were to: eliminate the particulate scrubber and its high maintenance costs, and incorporate flexibility for low-sulfur coal and possible stricter emission limits. Each of the three Dickerson 190 MW units has a small 37-year-old electrostatic precipitator and a wet particulate scrubber. The study evaluated alternatives to replace the scrubber and enhance ESP performance: Existing ESP alternatives--Extend height of existing ESP; Flue gas conditioning. Scrubber stream alternatives--Partial-flow ESP or pulse jet baghouse. Full-flow alternatives--Supplemental ESP; COHPAC baghouse; replacement ESP or baghouse. A technicalmore » and economic prescreening eliminated some of the options. Capital, operating, and life cycle costs were estimated for the remaining options to determine the most cost-effective alternative. This paper will present the technical and economic evaluations done for this study, including performance and costs.« less
Perera, F
1981-01-01
Benzo(a)pyrene(BaP) originating from fossil fuel and other organic combustion processes is largely adsorbed on fine particulate and hence is a widespread atmospheric pollutant. Available emissions and air quality data are based on the total weight of particulate matter without reference to size and give little information on trends and concentrations of fine particulate BaP. Greater reliance on coal, synfuels and diesel fuel for energy production and transportation will significantly increase ambient levels of BaP. Because of the particulate size, BaP is substantially deposited in the lower lung and readily eluted into surrounding tissue. After elution in the lung, BaP is metabolically activated to its electrophilic, carcinogenic from by a complex enzyme system whose activity is increased by prior exposure to air pollutants, cigarette smoke and certain drugs. The resultant diol epoxide metabolite has been shown to bind covalently with the DNA of the lung. In experimental animals, BaP is a potent initiating carcinogen whose action is enhanced by sulfur dioxide, promoting agents and carrier fine particles. The effect of small, divided doses of BaP has been shown to be greater than that of a single high dose; no threshold has been established. Epidemiological studies show that mixtures containing BaP (such as urban air, industrial emissions and cigarette smoke) are carcinogenic and may interact synergistically. Occupational studies indicate that the action of BaP-containing mixtures is enhanced in the presence of SO2. However, quantitative risk assessment for BaP is precluded by problems in extrapolating to the general population from small-scale animal studies; uncertainties in findings of epidemiology; and imprecise exposure data. Existing stationary and mobile controls preferentially remove coarse particulate matter and are inefficient collectors of the particulate BaP. In the current absence of health and environmental standards for BaP, there is little incentive to control BaP emissions. BaP meets the criteria for regulation under the Clean Air Act; however, no such BaP standards have yet been proposed. PMID:6277615
Hydrocarbon-enhanced particulate filter regeneration via microwave ignition
Gonze, Eugene V.; Brown, David B.
2010-02-02
A regeneration method for a particulate filter includes estimating a quantity of particulate matter trapped within the particulate filter, comparing the quantity of particulate matter to a predetermined quantity, heating at least a portion of the particulate filter to a combustion temperature of the particulate matter, and introducing hydrocarbon fuel to the particulate filter. The hydrocarbon fuel facilitates combustion of the particulate matter to regenerate the particulate filter.
This study was conducted to compare the cardiac effects of particulate matter (PM)-enhanced and ozone(O3)-enhanced smog atmospheres in mice. We hypothesized that O3-enhanced smog would cause greater cardiac dysfunction than PM-enhanced smog due to the higher concentrations of irr...
Mycobacterium abscessus Displays Fitness for Fomite Transmission
Caceres, Silvia M.; Honda, Jennifer R.; Davidson, Rebecca M.; Epperson, L. Elaine; Strong, Michael; Chan, Edward D.; Nick, Jerry A.
2017-01-01
ABSTRACT Mycobacterium abscessus is a rapidly growing nontuberculous mycobacterium (NTM) increasingly reported in soft tissue infections and chronic lung diseases, including cystic fibrosis. The environmental source of M. abscessus has not been definitively identified, but NTM have been detected in soil and water. To determine the potential of soil-derived M. abscessus as an infectious source, we explored the association, growth, and survival of M. abscessus with defined mineral particulates, including kaolin, halloysite, and silicone dioxide, and house dust as possible M. abscessus fomites. M. abscessus physically associated with particulates, and the growth of M. abscessus was enhanced in the presence of both kaolin and house dust. M. abscessus survived desiccation for 2 weeks but was not viable after 3 weeks. The rate of decline of M. abscessus viability during desiccation was reduced in the presence of house dust. The evidence for enhanced growth and survival of M. abscessus during alternating growth and drying periods suggests that dissemination could occur when in wet or dry environments. These studies are important to understand environmental survival and acquisition of NTM. IMPORTANCE The environmental source of pulmonary Mycobacterium abscessus infections is not known. Fomites are nonliving carriers of infectious agents and may contribute to acquisition of M. abscessus. This study provides evidence that M. abscessus growth is enhanced in the presence of particulates, using kaolin, an abundant natural clay mineral, and house dust as experimental fomites. Moreover, M. abscessus survived desiccation for up to 2 weeks in the presence of house dust, kaolin, and several chemically defined mineral particulates; mycobacterial viability during extended periods of dessication was enhanced by the presence of house dust. The growth characteristics of M. abscessus with particulates suggest that a fomite mechanism of transmission may contribute to M. abscessus acquisition, which may lead to strategies to better control infections by M. abscessus and related organisms. PMID:28754702
Electrically heated particulate filter propagation support methods and systems
Gonze, Eugene V [Pinckney, MI; Ament, Frank [Troy, MI
2011-06-07
A control system that controls regeneration of a particulate filter is provided. The system generally includes a regeneration module that controls current to the particulate filter to initiate combustion of particulate matter in the particulate filter. A propagation module estimates a propagation status of the combustion of the particulate matter based on a combustion temperature. A temperature adjustment module controls the combustion temperature by selectively increasing a temperature of exhaust that passes through the particulate filter.
Report #2005-P-00004, February 7, 2005. EPA has made substantial progress in establishing a speciation monitoring network, but still faces a number of challenges in ensuring that the controls are implemented at the right sources.
40 CFR 52.2059 - Control strategy: Particulate matter.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 5 2012-07-01 2012-07-01 false Control strategy: Particulate matter... Control strategy: Particulate matter. (a) Pennsylvania has committed to undertake a comprehensive program... Investigating and Controlling Nontraditional Particulate Matter Emissions Task Completion date Scheduled tasks...
40 CFR 52.2059 - Control strategy: Particulate matter.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 5 2013-07-01 2013-07-01 false Control strategy: Particulate matter... Control strategy: Particulate matter. (a) Pennsylvania has committed to undertake a comprehensive program... Investigating and Controlling Nontraditional Particulate Matter Emissions Task Completion date Scheduled tasks...
40 CFR 52.2059 - Control strategy: Particulate matter.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy: Particulate matter... Control strategy: Particulate matter. (a) Pennsylvania has committed to undertake a comprehensive program... Investigating and Controlling Nontraditional Particulate Matter Emissions Task Completion date Scheduled tasks...
40 CFR 52.2059 - Control strategy: Particulate matter.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy: Particulate matter... Control strategy: Particulate matter. (a) Pennsylvania has committed to undertake a comprehensive program... Investigating and Controlling Nontraditional Particulate Matter Emissions Task Completion date Scheduled tasks...
40 CFR 1042.125 - Maintenance instructions.
Code of Federal Regulations, 2011 CFR
2011-07-01
... CONTROLS CONTROL OF EMISSIONS FROM NEW AND IN-USE MARINE COMPRESSION-IGNITION ENGINES AND VESSELS Emission... converters, electronic control units, particulate traps, trap oxidizers, components related to particulate..., electronic control units, particulate traps, trap oxidizers, components related to particulate traps and trap...
40 CFR 1042.125 - Maintenance instructions.
Code of Federal Regulations, 2013 CFR
2013-07-01
... CONTROLS CONTROL OF EMISSIONS FROM NEW AND IN-USE MARINE COMPRESSION-IGNITION ENGINES AND VESSELS Emission... converters, electronic control units, particulate traps, trap oxidizers, components related to particulate..., electronic control units, particulate traps, trap oxidizers, components related to particulate traps and trap...
40 CFR 1042.125 - Maintenance instructions.
Code of Federal Regulations, 2014 CFR
2014-07-01
... CONTROLS CONTROL OF EMISSIONS FROM NEW AND IN-USE MARINE COMPRESSION-IGNITION ENGINES AND VESSELS Emission... converters, electronic control units, particulate traps, trap oxidizers, components related to particulate..., electronic control units, particulate traps, trap oxidizers, components related to particulate traps and trap...
40 CFR 1042.125 - Maintenance instructions.
Code of Federal Regulations, 2012 CFR
2012-07-01
... CONTROLS CONTROL OF EMISSIONS FROM NEW AND IN-USE MARINE COMPRESSION-IGNITION ENGINES AND VESSELS Emission... converters, electronic control units, particulate traps, trap oxidizers, components related to particulate..., electronic control units, particulate traps, trap oxidizers, components related to particulate traps and trap...
Electrically heated particulate filter restart strategy
Gonze, Eugene V [Pinckney, MI; Ament, Frank [Troy, MI
2011-07-12
A control system that controls regeneration of a particulate filter is provided. The system generally includes a propagation module that estimates a propagation status of combustion of particulate matter in the particulate filter. A regeneration module controls current to the particulate filter to re-initiate regeneration based on the propagation status.
NASA Astrophysics Data System (ADS)
Arellano, A. R.; Bianchi, T. S.; Osburn, C. L.; D'Sa, E. J.; Oviedo-Vargas, D.; Ward, N. D.; Joshi, I.
2017-12-01
While most blue carbon habitat (wetlands, seagrass beds and mangroves) research has focused on carbon burial/stocks and habitat fragmentation of these communities, few studies have examined physical factors that control exports and losses of blue carbon sources of organic matter (OM) to adjacent coastal waters. Here, we report on spatiotemporal changes in the composition and concentration of dissolved organic carbon (DOC), particulate organic carbon (POC), particulate nitrogen, pCO2, δ13C-DOC, δ13C-POC, δ13C-CO2, dissolved lignin-phenols (dΣ8), particulate lignin-phenols (pΣ8) and carbon normalized dissolved and particulate lignin phenol yields (dΛ8 and pΛ8) in surface waters of the Apalachicola and Barataria bays in the Gulf of Mexico. Discriminant analysis described spatial variability along canonical axis I (24.4%) while temporal variability was explained by canonical axis II (23.2%). Apalachicola Bay was low in POC concentration and characterized by high values for pCO2, DOC, C:N, dΣ8 and (Ad:Al)V. The latter three parameters indicated a clear terrestrial source of OM at Apalachicola Bay reflecting the importance of riverine DOM inputs in this system. In contrast, Barataria Bay was characterized by high values for POC, C:V, S:V, and δ13C-POC, indicating blue-carbon sources due to a lack of direct river inputs and high prevalence of wetlands, some recently submerged. Extreme weather, such as intense precipitation events in Apalachicola Bay and enhanced northerly winds in Barataria Bay were characterized by δ13C-CO2, dΛ8, C:V (Barataria), and C:N (Apalachicola). Results indicate that such physical factors can exert strong control on OM sources and sinks across the gradient of coastal wetlands and shelf waters and lead to enhanced transfer and degradation of wetland-derived blue carbon in coastal waters.
Electrically heated particulate filter preparation methods and systems
Gonze, Eugene V [Pinckney, MI
2012-01-31
A control system that controls regeneration of a particulate filter is provided. The system generally includes a fuel control module that controls injection of fuel into exhaust that passes through the particulate filter. A regeneration module controls current to the particulate filter to initiate regeneration after the fuel has been injected into the exhaust.
Electrically heated particulate filter regeneration methods and systems for hybrid vehicles
Gonze, Eugene V.; Paratore, Jr., Michael J.
2010-10-12
A control system for controlling regeneration of a particulate filter for a hybrid vehicle is provided. The system generally includes a regeneration module that controls current to the particulate filter to initiate regeneration. An engine control module controls operation of an engine of the hybrid vehicle based on the control of the current to the particulate filter.
40 CFR 52.2584 - Control strategy; Particulate matter.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy; Particulate matter... Control strategy; Particulate matter. (a) Part D—Disapproval—USEPA disapproves Regulation NR 154.11(7)(b... control strategy to attain and maintain the standards for particulate matter, because it does not contain...
40 CFR 52.2584 - Control strategy; Particulate matter.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 5 2014-07-01 2014-07-01 false Control strategy; Particulate matter... Control strategy; Particulate matter. (a) Part D—Disapproval—USEPA disapproves Regulation NR 154.11(7)(b... control strategy to attain and maintain the standards for particulate matter, because it does not contain...
40 CFR 52.2584 - Control strategy; Particulate matter.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 5 2013-07-01 2013-07-01 false Control strategy; Particulate matter... Control strategy; Particulate matter. (a) Part D—Disapproval—USEPA disapproves Regulation NR 154.11(7)(b... control strategy to attain and maintain the standards for particulate matter, because it does not contain...
40 CFR 52.2584 - Control strategy; Particulate matter.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 5 2012-07-01 2012-07-01 false Control strategy; Particulate matter... Control strategy; Particulate matter. (a) Part D—Disapproval—USEPA disapproves Regulation NR 154.11(7)(b... control strategy to attain and maintain the standards for particulate matter, because it does not contain...
40 CFR 52.2584 - Control strategy; Particulate matter.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy; Particulate matter... Control strategy; Particulate matter. (a) Part D—Disapproval—USEPA disapproves Regulation NR 154.11(7)(b... control strategy to attain and maintain the standards for particulate matter, because it does not contain...
Code of Federal Regulations, 2011 CFR
2011-07-01
... flue gases at the inlet of my particulate matter control device? 60.1325 Section 60.1325 Protection of... the inlet of my particulate matter control device? You must install, calibrate, maintain, and operate... particulate matter control device. ...
Code of Federal Regulations, 2010 CFR
2010-07-01
... flue gases at the inlet of my particulate matter control device? 60.1325 Section 60.1325 Protection of... the inlet of my particulate matter control device? You must install, calibrate, maintain, and operate... particulate matter control device. ...
The two-volume proceedings describe the latest research and development efforts to improve particulate control devices, while treating traditional concerns of operational cost and compliance. Overall, particulate control remains a key issue in the cost and applicability of furnac...
NASA Astrophysics Data System (ADS)
Paladino, J. D.; Hagen, D. E.; Whitefield, P. D.; Hopkins, A. R.; Schmid, O.; Wilson, M. R.; Schlager, H.; Schulte, P.
2000-02-01
This paper discusses participate concentration and size distribution data gathered using the University of Missouri-Rolla Mobile Aerosol Sampling System (UMR-MASS), and used to investigate the southern extent of the eastern end of the North Atlantic Flight Corridor (NAFC) during project Pollution From Aircraft Emissions in the North Atlantic Flight Corridor/Subsonic Assessment (SASS) Ozone and Nitrogen Oxide Experiment (POLINAT 2/SONEX) from September 19 to October 23, 1997. The analysis presented in this paper focuses on "the corridor effect," or enhancement of pollutants by jet aircraft combustion events. To investigate the phenomena, both vertical and horizontal profiles of the corridor, and regions immediately adjacent to the corridor, were performed. The profiles showed a time-dependent enhancement of particulates within the corridor, and a nonvolatile (with respect to thermal volatilization at 300°C) aerosol enhancement at corridor altitudes by a factor of 3.6. The southern extent of the North Atlantic Flight Corridor was established from a four flight average of the particulate data and yielded a boundary near 42.5°N during the study period. A size distribution analysis of the nonvolatile particulates revealed an enhancement in the <40 nm particulates for size distributions recorded within the flight corridor.
40 CFR 52.1678 - Control strategy and regulations: Particulate matter.
Code of Federal Regulations, 2011 CFR
2011-07-01
...: Particulate matter. 52.1678 Section 52.1678 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... § 52.1678 Control strategy and regulations: Particulate matter. (a)-(c) [Reserved] (d) Section 227.3(a... CFR Subpart G, Control strategy: Sulfur oxides and particulate matter. (e) Determination of Attainment...
NASA Astrophysics Data System (ADS)
Riou, V.; Para, J.; Garel, M.; Guigue, C.; Al Ali, B.; Santinelli, C.; Lefèvre, D.; Gattuso, J. P.; Goutx, M.; Panagiotopoulos, C.; Beaufort, L.; Jacquet, S.; Le Moigne, F. A. C.; Tachikawa, K.; Tamburini, C.
2016-02-01
Fluxes of particulate organic carbon (POC) and minerals are positively correlated, suggesting that minerals could enhance the flux of POC into the deep ocean. The so called "ballast effect" posits that minerals could increase sinking particle densities and/or protect the organic matter from heterotrophic degradation. Laboratory controlled experiments on coccolithophorid aggregates under atmospheric pressure show that biogenic calcite both increases particle settling velocities and preserves the organic matter. However, such experiments have yet to include genuine prokaryote rates indicators as well as the effect of increasing pressure. Here, we used the PArticle Sinking Simulator (PASS) to investigate the effect of the increasing pressure on the degradation of Emiliania huxleyi (calcifiers) aggregates. Extra care was taken to obtain culture aggregates with low prokaryotic abundance prior to exposure to natural mesopelagic prokaryotic communities. Particulate organic and inorganic carbon and dissolved organic carbon concentrations were monitored along with the lipid and carbohydrate compositions, as well as prokaryotic community abundance and specific diversity. A control experiment, without natural prokaryotic community addition, indicates that the pressure increase did not have any effect on calcite dissolution observed after ten days. In contrast, the addition of natural prokaryotic community accelerates calcite dissolution under conditions of increasing pressure. Prokaryotic community development and the lipid fraction of E. huxleyi particulate organic carbon are enhanced under increasing pressure. These results suggest that hydrostatic pressure denatures the structural integrity of the carbonate skeleton that protects the cellular organic matter.
40 CFR 52.2059 - Control strategy: Particulate matter.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 5 2014-07-01 2014-07-01 false Control strategy: Particulate matter... Control strategy: Particulate matter. (a) [Reserved] (b) EPA approves the PM-10 attainment demonstration...-Wilmington, PA-NJ-DE fine particulate matter (PM2.5) nonattainment area has attained the 2006 24-hour PM2.5...
Code of Federal Regulations, 2011 CFR
2011-07-01
... flue gases at the inlet of my particulate matter control device? 60.1815 Section 60.1815 Protection of... I monitor the temperature of flue gases at the inlet of my particulate matter control device? You... flue gas stream at the inlet of each particulate matter control device. ...
Code of Federal Regulations, 2010 CFR
2010-07-01
... flue gases at the inlet of my particulate matter control device? 60.1815 Section 60.1815 Protection of... I monitor the temperature of flue gases at the inlet of my particulate matter control device? You... flue gas stream at the inlet of each particulate matter control device. ...
Code of Federal Regulations, 2010 CFR
2010-07-01
... flue gases at the inlet of my particulate matter control device? 62.15270 Section 62.15270 Protection....15270 How do I monitor the temperature of flue gases at the inlet of my particulate matter control... temperature of the flue gas stream at the inlet of each particulate matter control device. ...
Code of Federal Regulations, 2011 CFR
2011-07-01
... flue gases at the inlet of my particulate matter control device? 62.15270 Section 62.15270 Protection....15270 How do I monitor the temperature of flue gases at the inlet of my particulate matter control... temperature of the flue gas stream at the inlet of each particulate matter control device. ...
PARTICULATE EMISSIONS AND CONTROL IN FLUIDIZED-BED COMBUSTION: MODELING AND PARAMETRIC PERFORMANCE
The report discusses a model, developed to describe the physical characteristics of the particulates emitted from fluidized-bed combustion (FBC) systems and to evaluate data on FBC particulate control systems. The model, which describes the particulate emissions profile from FBC,...
40 CFR 52.776 - Control strategy: Particulate matter.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 3 2013-07-01 2013-07-01 false Control strategy: Particulate matter...: Particulate matter. Link to an amendment published at 78 FR 28507, May 15, 2013. (a) The requirements of... the secondary standards for particulate matter in the Metropolitan Indianapolis Intrastate Region. (b...
40 CFR 52.2276 - Control strategy and regulations: Particulate matter.
Code of Federal Regulations, 2011 CFR
2011-07-01
...: Particulate matter. 52.2276 Section 52.2276 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY....2276 Control strategy and regulations: Particulate matter. (a) Part D conditional approval. The Texas... of the fabric filters, Parker Brothers and Co., Inc., shall not emit particulate matter in excess of...
Engine Valve Actuation For Combustion Enhancement
Reitz, Rolf Deneys; Rutland, Christopher J.; Jhavar, Rahul
2004-05-18
A combustion chamber valve, such as an intake valve or an exhaust valve, is briefly opened during the compression and/or power strokes of a 4-stroke combustion cycle in an internal combustion engine (in particular, a diesel or CI engine). The brief opening may (1) enhance mixing withing the combustion chamber, allowing more complete oxidation of particulates to decrease engine emissions; and/or may (2) delay ignition until a more desirable time, potentially allowing a means of timing ignition in otherwise difficult-to-control conditions, e.g., in HCCI (Homogeneous Charge Compression Ignition) conditions.
Engine valve actuation for combustion enhancement
Reitz, Rolf Deneys [Madison, WI; Rutland, Christopher J [Madison, WI; Jhavar, Rahul [Madison, WI
2008-03-04
A combustion chamber valve, such as an intake valve or an exhaust valve, is briefly opened during the compression and/or power strokes of a 4-strokes combustion cycle in an internal combustion engine (in particular, a diesel or CI engine). The brief opening may (1) enhance mixing withing the combustion chamber, allowing more complete oxidation of particulates to decrease engine emissions; and/or may (2) delay ignition until a more desirable time, potentially allowing a means of timing ignition in otherwise difficult-to-control conditions, e.g., in HCCI (Homogeneous Charge Compression Ignition) conditions.
40 CFR 52.1781 - Control strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy: Sulfur oxides and particulate matter. 52.1781 Section 52.1781 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Carolina § 52.1781 Control strategy: Sulfur oxides and particulate matter. (a) The plan's control strategy...
40 CFR 52.1781 - Control strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy: Sulfur oxides and particulate matter. 52.1781 Section 52.1781 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Carolina § 52.1781 Control strategy: Sulfur oxides and particulate matter. (a) The plan's control strategy...
40 CFR 52.1476 - Control strategy: Particulate matter.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 4 2014-07-01 2014-07-01 false Control strategy: Particulate matter... strategy: Particulate matter. (a) The requirements of subpart G of this chapter are not met since the plan does not provide for the attainment and maintenance of the national standards for particulate matter in...
40 CFR 52.1476 - Control strategy: Particulate matter.
Code of Federal Regulations, 2010 CFR
2010-07-01
... National Ambient Air Quality Standards for particulate matter. (1) NAQR Article 7.2.7, Particulate Matter; Table 4.2, Emissions Inventory Summary for Particulates and Table 5.2, Summary of Control Strategy... 24, 1979. (2) Nevada Air Quality Regulations, Article 4, Rule 4.34, (Visible Emission from Stationary...
40 CFR 52.776 - Control strategy: Particulate matter.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 3 2014-07-01 2014-07-01 false Control strategy: Particulate matter...: Particulate matter. (a) The requirements of subpart G of this chapter are not met since the plan does not provide for attainment and maintenance of the secondary standards for particulate matter in the...
40 CFR 52.776 - Control strategy: Particulate matter.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 3 2012-07-01 2012-07-01 false Control strategy: Particulate matter...: Particulate matter. (a) The requirements of subpart G of this chapter are not met since the plan does not provide for attainment and maintenance of the secondary standards for particulate matter in the...
40 CFR 52.1476 - Control strategy: Particulate matter.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy: Particulate matter... strategy: Particulate matter. (a) The requirements of subpart G of this chapter are not met since the plan does not provide for the attainment and maintenance of the national standards for particulate matter in...
40 CFR 52.1476 - Control strategy: Particulate matter.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 4 2013-07-01 2013-07-01 false Control strategy: Particulate matter... strategy: Particulate matter. (a) The requirements of subpart G of this chapter are not met since the plan does not provide for the attainment and maintenance of the national standards for particulate matter in...
40 CFR 52.1476 - Control strategy: Particulate matter.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 4 2012-07-01 2012-07-01 false Control strategy: Particulate matter... strategy: Particulate matter. (a) The requirements of subpart G of this chapter are not met since the plan does not provide for the attainment and maintenance of the national standards for particulate matter in...
Code of Federal Regulations, 2010 CFR
2010-07-01
...: Particulate matter, Metropolitan Los Angeles Intrastate Region. 52.227 Section 52.227 Protection of... IMPLEMENTATION PLANS California § 52.227 Control strategy and regulations: Particulate matter, Metropolitan Los... does not provide for attainment and maintenance of the secondary standards for particulate matter in...
Code of Federal Regulations, 2011 CFR
2011-07-01
...: Particulate matter, Metropolitan Los Angeles Intrastate Region. 52.227 Section 52.227 Protection of... IMPLEMENTATION PLANS California § 52.227 Control strategy and regulations: Particulate matter, Metropolitan Los... does not provide for attainment and maintenance of the secondary standards for particulate matter in...
40 CFR 52.2429 - Control strategy: Particulate matter.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy: Particulate matter. 52.2429 Section 52.2429 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy: Particulate matter. Determination of Attainment. EPA has determined, as of January 12...
40 CFR 52.477 - Control strategy: Particulate matter.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 3 2014-07-01 2014-07-01 false Control strategy: Particulate matter. 52.477 Section 52.477 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy: Particulate matter. Determination of Attainment. EPA has determined, as of January 12...
40 CFR 52.477 - Control strategy: Particulate matter.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 3 2013-07-01 2013-07-01 false Control strategy: Particulate matter. 52.477 Section 52.477 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy: Particulate matter. Determination of Attainment. EPA has determined, as of January 12...
40 CFR 52.1081 - Control strategy: Particulate matter.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 4 2013-07-01 2013-07-01 false Control strategy: Particulate matter. 52.1081 Section 52.1081 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy: Particulate matter. (a) Determination of Attainment. EPA has determined, as of January...
40 CFR 52.2429 - Control strategy: Particulate matter.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 5 2013-07-01 2013-07-01 false Control strategy: Particulate matter. 52.2429 Section 52.2429 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy: Particulate matter. Determination of Attainment. EPA has determined, as of January 12...
40 CFR 52.1131 - Control strategy: Particulate matter.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy: Particulate matter. 52.1131 Section 52.1131 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy: Particulate matter. (a) Revisions to the following regulations submitted on March 30...
40 CFR 52.1131 - Control strategy: Particulate matter.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy: Particulate matter. 52.1131 Section 52.1131 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy: Particulate matter. (a) Revisions to the following regulations submitted on March 30...
40 CFR 52.477 - Control strategy: Particulate matter.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 3 2012-07-01 2012-07-01 false Control strategy: Particulate matter. 52.477 Section 52.477 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy: Particulate matter. Determination of Attainment. EPA has determined, as of January 12...
40 CFR 52.1081 - Control strategy: Particulate matter.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 4 2012-07-01 2012-07-01 false Control strategy: Particulate matter. 52.1081 Section 52.1081 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy: Particulate matter. (a) Determination of Attainment. EPA has determined, as of January...
40 CFR 52.2429 - Control strategy: Particulate matter.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 5 2012-07-01 2012-07-01 false Control strategy: Particulate matter. 52.2429 Section 52.2429 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy: Particulate matter. Determination of Attainment. EPA has determined, as of January 12...
40 CFR 52.1131 - Control strategy: Particulate matter.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 4 2012-07-01 2012-07-01 false Control strategy: Particulate matter. 52.1131 Section 52.1131 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy: Particulate matter. (a) Revisions to the following regulations submitted on March 30...
40 CFR 52.477 - Control strategy: Particulate matter.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 3 2011-07-01 2011-07-01 false Control strategy: Particulate matter. 52.477 Section 52.477 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy: Particulate matter. Determination of Attainment. EPA has determined, as of January 12...
40 CFR 52.1081 - Control strategy: Particulate matter.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy: Particulate matter. 52.1081 Section 52.1081 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy: Particulate matter. (a) Determination of Attainment. EPA has determined, as of January...
40 CFR 52.1081 - Control strategy: Particulate matter.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 4 2014-07-01 2014-07-01 false Control strategy: Particulate matter. 52.1081 Section 52.1081 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy: Particulate matter. (a) Determination of Attainment. EPA has determined, as of January...
40 CFR 52.2429 - Control strategy: Particulate matter.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 5 2014-07-01 2014-07-01 false Control strategy: Particulate matter. 52.2429 Section 52.2429 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy: Particulate matter. Determination of Attainment. EPA has determined, as of January 12...
40 CFR 52.1081 - Control strategy: Particulate matter.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy: Particulate matter. 52.1081 Section 52.1081 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy: Particulate matter. (a) Determination of Attainment. EPA has determined, as of January...
40 CFR 52.2429 - Control strategy: Particulate matter.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy: Particulate matter. 52.2429 Section 52.2429 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy: Particulate matter. Determination of Attainment. EPA has determined, as of January 12...
40 CFR 52.477 - Control strategy: Particulate matter.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Control strategy: Particulate matter. 52.477 Section 52.477 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy: Particulate matter. Determination of Attainment. EPA has determined, as of January 12...
NASA Astrophysics Data System (ADS)
Kunuku, Srinivasu; Chen, Yen-Chun; Yeh, Chien-Jui; Chang, Wen-Hao; Manoharan, Divinah; Leou, Keh-Chyang; Lin, I.-Nan
2016-10-01
We report the synthesis of silicon-vacancy (SiV) incorporated spherical shaped ultrananocrystalline diamond (SiV-UNCD) particulates (size ∼1 μm) with bright luminescence at 738 nm. For this purpose, different granular structured polycrystalline diamond films and particulates were synthesized by using three different kinds of growth plasma conditions on the three types of substrate materials in the microwave plasma enhanced CVD process. The grain size dependent photoluminescence properties of nitrogen vacancy (NV) and SiV color centers have been investigated for different granular structured diamond samples. The luminescence of NV center and the associated phonon sidebands, which are usually observed in microcrystalline diamond and nanocrystalline diamond films, were effectively suppressed in UNCD films and UNCD particulates. Micron sized SiV-UNCD particulates with bright SiV emission has been attained by transfer of SiV-UNCD clusters on soda-lime glass fibers to inverted pyramidal cavities fabricated on Si substrates by the simple crushing of UNCD/soda-lime glass fibers in deionized water and ultrasonication. Such a plasma enhanced CVD process for synthesizing SiV-UNCD particulates with suppressed NV emission is simple and robust to attain the bright SiV-UNCD particulates to employ in practical applications.
Uptake of particulate vaccine adjuvants by dendritic cells activates the NALP3 inflammasome.
Sharp, Fiona A; Ruane, Darren; Claass, Benjamin; Creagh, Emma; Harris, James; Malyala, Padma; Singh, Manomohan; O'Hagan, Derek T; Pétrilli, Virginie; Tschopp, Jurg; O'Neill, Luke A J; Lavelle, Ed C
2009-01-20
Many currently used and candidate vaccine adjuvants are particulate in nature, but their mechanism of action is not well understood. Here, we show that particulate adjuvants, including biodegradable poly(lactide-co-glycolide) (PLG) and polystyrene microparticles, dramatically enhance secretion of interleukin-1beta (IL-1beta) by dendritic cells (DCs). The ability of particulates to promote IL-1beta secretion and caspase 1 activation required particle uptake by DCs and NALP3. Uptake of microparticles induced lysosomal damage, whereas particle-mediated enhancement of IL-1beta secretion required phagosomal acidification and the lysosomal cysteine protease cathepsin B, suggesting a role for lysosomal damage in inflammasome activation. Although the presence of a Toll-like receptor (TLR) agonist was required to induce IL-1beta production in vitro, injection of the adjuvants in the absence of TLR agonists induced IL-1beta production at the injection site, indicating that endogenous factors can synergize with particulates to promote inflammasome activation. The enhancement of antigen-specific antibody production by PLG microparticles was independent of NALP3. However, the ability of PLG microparticles to promote antigen-specific IL-6 production by T cells and the recruitment and activation of a population of CD11b(+)Gr1(-) cells required NALP3. Our data demonstrate that uptake of microparticulate adjuvants by DCs activates the NALP3 inflammasome, and this contributes to their enhancing effects on innate and antigen-specific cellular immunity.
40 CFR 52.427 - Control strategy: Particulate matter.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 3 2013-07-01 2013-07-01 false Control strategy: Particulate matter...: Particulate matter. (a) Determination of attainment. EPA has determined, as of May 16, 2012, that based on... fine particulate matter (PM2.5) nonattainment area has attained the 2006 24-hour PM2.5 national ambient...
40 CFR 52.427 - Control strategy: Particulate matter.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 3 2014-07-01 2014-07-01 false Control strategy: Particulate matter...: Particulate matter. (a) Determination of attainment. EPA has determined, as of May 16, 2012, that based on... fine particulate matter (PM2.5) nonattainment area has attained the 2006 24-hour PM2.5 national ambient...
40 CFR 52.2526 - Control strategy: Particulate matter.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy: Particulate matter. 52.2526 Section 52.2526 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy: Particulate matter. (a) EPA approves West Virginia's November 15, 1991 SIP submittal for...
40 CFR 52.1374 - Control strategy: Particulate matter.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy: Particulate matter. 52.1374 Section 52.1374 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy: Particulate matter. (a) On July 8, 1997, the Governor of Montana submitted minor...
40 CFR 52.1025 - Control strategy: Particulate matter.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy: Particulate matter. 52.1025 Section 52.1025 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... strategy: Particulate matter. (a) The revisions to the control strategy resulting from the modification to...
40 CFR 52.1374 - Control strategy: Particulate matter.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 4 2014-07-01 2014-07-01 false Control strategy: Particulate matter. 52.1374 Section 52.1374 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy: Particulate matter. (a) On July 8, 1997, the Governor of Montana submitted minor...
40 CFR 52.1374 - Control strategy: Particulate matter.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 4 2013-07-01 2013-07-01 false Control strategy: Particulate matter. 52.1374 Section 52.1374 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy: Particulate matter. (a) On July 8, 1997, the Governor of Montana submitted minor...
40 CFR 52.1341 - Control strategy: particulate matter.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy: particulate matter. 52.1341 Section 52.1341 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy: particulate matter. Determination of Attainment. EPA has determined, as of May 23, 2011...
40 CFR 52.2526 - Control strategy: Particulate matter.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 5 2012-07-01 2012-07-01 false Control strategy: Particulate matter. 52.2526 Section 52.2526 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy: Particulate matter. (a) EPA approves West Virginia's November 15, 1991 SIP submittal for...
40 CFR 52.1025 - Control strategy: Particulate matter.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 4 2012-07-01 2012-07-01 false Control strategy: Particulate matter. 52.1025 Section 52.1025 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... strategy: Particulate matter. (a) The revisions to the control strategy resulting from the modification to...
40 CFR 52.2526 - Control strategy: Particulate matter.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 5 2013-07-01 2013-07-01 false Control strategy: Particulate matter. 52.2526 Section 52.2526 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy: Particulate matter. (a) EPA approves West Virginia's November 15, 1991 SIP submittal for...
40 CFR 52.2526 - Control strategy: Particulate matter.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 5 2014-07-01 2014-07-01 false Control strategy: Particulate matter. 52.2526 Section 52.2526 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy: Particulate matter. (a) EPA approves West Virginia's November 15, 1991 SIP submittal for...
40 CFR 52.1374 - Control strategy: Particulate matter.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 4 2012-07-01 2012-07-01 false Control strategy: Particulate matter. 52.1374 Section 52.1374 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy: Particulate matter. (a) On July 8, 1997, the Governor of Montana submitted minor...
40 CFR 52.1374 - Control strategy: Particulate matter.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy: Particulate matter. 52.1374 Section 52.1374 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy: Particulate matter. (a) On July 8, 1997, the Governor of Montana submitted minor...
40 CFR 52.1025 - Control strategy: Particulate matter.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 4 2013-07-01 2013-07-01 false Control strategy: Particulate matter. 52.1025 Section 52.1025 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... strategy: Particulate matter. (a) The revisions to the control strategy resulting from the modification to...
40 CFR 52.1341 - Control strategy: particulate matter.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 4 2012-07-01 2012-07-01 false Control strategy: particulate matter. 52.1341 Section 52.1341 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy: particulate matter. Determination of Attainment. EPA has determined, as of May 23, 2011...
40 CFR 52.1025 - Control strategy: Particulate matter.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 4 2014-07-01 2014-07-01 false Control strategy: Particulate matter. 52.1025 Section 52.1025 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... strategy: Particulate matter. (a) The revisions to the control strategy resulting from the modification to...
40 CFR 52.2526 - Control strategy: Particulate matter.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy: Particulate matter. 52.2526 Section 52.2526 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy: Particulate matter. (a) EPA approves West Virginia's November 15, 1991 SIP submittal for...
An enhanced research paradigm is presented to address the spatial and temporal gaps in fine particulate matter (PM2.5) measurements and generate realistic and representative concentration fields for use in epidemiological studies of human exposure to ambient air particulate conce...
The two-volume proceedings describe the latest research and development efforts to improve particulate control devices, while treating traditional concerns of operational cost and compliance. Overall, particulate control remains a key issue in the cost and applicability of furnac...
40 CFR 52.2678 - Control strategy and regulations: Particulate matter.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy and regulations: Particulate matter. 52.2678 Section 52.2678 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY....2678 Control strategy and regulations: Particulate matter. (a) The requirements of § 51.110(a) and...
40 CFR 52.2678 - Control strategy and regulations: Particulate matter.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy and regulations: Particulate matter. 52.2678 Section 52.2678 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY....2678 Control strategy and regulations: Particulate matter. (a) The requirements of § 51.110(a) and...
Pirie, R S; Collie, D D S; Dixon, P M; McGorum, B C
2003-05-01
Equine heaves is a naturally occurring organic dust-induced asthma characterized by airway neutrophilia, mucus hypersecretion and obstructive lung dysfunction. However, the relative role of different dust components in disease severity remains unclear. This study investigated the relative contribution of inhaled endotoxin and organic dust particulates (mainly mould spores) in inducing heaves in heaves-susceptible horses. Control and heaves-susceptible horses received inhalation challenges with hay dust suspension (HDS) before and after lipopolysaccharide (LPS) depletion. Heaves-susceptible horses also received inhalation challenge with HDS particulates with and without the addition of LPS and were housed in two separate dusty environments during which mould and endotoxin exposure was measured. The airway inflammatory and functional response to each challenge was measured. Depletion of endotoxin from HDS attenuated the airway neutrophilia and abrogated the airway dysfunction induced in heaves horses by inhaled HDS. The airway response was re-established by adding back LPS to the depleted HDS, confirming that the attenuation in airway response was due specifically to endotoxin depletion. Interestingly, the magnitude of alteration in airway response following endotoxin depletion and add-back was greater than that which could be attributed solely to endotoxin per se, indicating that the LPS activity was enhanced by the other dust components. Consistent with this possibility, washed particulates harvested from HDS enhanced the airway response to inhaled LPS in heaves horses. Heaves horses given two different hay/straw challenges had a significantly different severity of airway inflammation and dysfunction, despite airborne dust and endotoxin concentrations in the horses' breathing zones being similar. Although inhaled endotoxin appears not to be the only determinant of disease severity in heaves, it does contribute significantly to the induction of airway inflammation and dysfunction. This contribution is largely via the synergistic action of inhaled endotoxin and organic dust particulates, although other soluble dust components also contribute to a lesser degree.
40 CFR 52.275 - Particulate matter control.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 3 2012-07-01 2012-07-01 false Particulate matter control. 52.275 Section 52.275 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS California § 52.275 Particulate matter control. (a) The following rules or portions of rules...
40 CFR 52.275 - Particulate matter control.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 3 2013-07-01 2013-07-01 false Particulate matter control. 52.275 Section 52.275 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS California § 52.275 Particulate matter control. (a) The following rules or portions of rules...
40 CFR 52.275 - Particulate matter control.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 3 2011-07-01 2011-07-01 false Particulate matter control. 52.275 Section 52.275 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS California § 52.275 Particulate matter control. (a) The following rules or portions of rules...
40 CFR 52.275 - Particulate matter control.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 3 2014-07-01 2014-07-01 false Particulate matter control. 52.275 Section 52.275 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS California § 52.275 Particulate matter control. (a) The following rules or portions of rules...
The proceedings document presentations from the seventh symposium on the transfer and utilization of particulate control technology, March 22-25, 1988, in Nashville, TN. Objectives of the symposium were to encourage the exchange of new knowledge in the particulate control field b...
40 CFR 52.2231 - Control strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy: Sulfur oxides and particulate matter. 52.2231 Section 52.2231 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... § 52.2231 Control strategy: Sulfur oxides and particulate matter. (a) Part D conditional approval. The...
40 CFR 52.1278 - Control strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy: Sulfur oxides and particulate matter. 52.1278 Section 52.1278 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...) Mississippi § 52.1278 Control strategy: Sulfur oxides and particulate matter. In a letter dated January 30...
40 CFR 52.2231 - Control strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 5 2012-07-01 2012-07-01 false Control strategy: Sulfur oxides and particulate matter. 52.2231 Section 52.2231 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... § 52.2231 Control strategy: Sulfur oxides and particulate matter. (a) Part D conditional approval. The...
40 CFR 52.2231 - Control strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy: Sulfur oxides and particulate matter. 52.2231 Section 52.2231 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... § 52.2231 Control strategy: Sulfur oxides and particulate matter. (a) Part D conditional approval. The...
40 CFR 52.2130 - Control strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 5 2013-07-01 2013-07-01 false Control strategy: Sulfur oxides and particulate matter. 52.2130 Section 52.2130 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Carolina § 52.2130 Control strategy: Sulfur oxides and particulate matter. In letters dated May 7, and...
40 CFR 52.1278 - Control strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy: Sulfur oxides and particulate matter. 52.1278 Section 52.1278 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...) Mississippi § 52.1278 Control strategy: Sulfur oxides and particulate matter. In a letter dated January 30...
40 CFR 52.1278 - Control strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 4 2013-07-01 2013-07-01 false Control strategy: Sulfur oxides and particulate matter. 52.1278 Section 52.1278 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...) Mississippi § 52.1278 Control strategy: Sulfur oxides and particulate matter. (a) In a letter dated January 30...
40 CFR 52.2231 - Control strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 5 2013-07-01 2013-07-01 false Control strategy: Sulfur oxides and particulate matter. 52.2231 Section 52.2231 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... § 52.2231 Control strategy: Sulfur oxides and particulate matter. (a) Part D conditional approval. The...
40 CFR 52.2130 - Control strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy: Sulfur oxides and particulate matter. 52.2130 Section 52.2130 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Carolina § 52.2130 Control strategy: Sulfur oxides and particulate matter. In letters dated May 7, and...
40 CFR 52.1278 - Control strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 4 2012-07-01 2012-07-01 false Control strategy: Sulfur oxides and particulate matter. 52.1278 Section 52.1278 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...) Mississippi § 52.1278 Control strategy: Sulfur oxides and particulate matter. In a letter dated January 30...
40 CFR 52.2231 - Control strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 5 2014-07-01 2014-07-01 false Control strategy: Sulfur oxides and particulate matter. 52.2231 Section 52.2231 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... § 52.2231 Control strategy: Sulfur oxides and particulate matter. (a) Part D conditional approval. The...
40 CFR 52.1278 - Control strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 4 2014-07-01 2014-07-01 false Control strategy: Sulfur oxides and particulate matter. 52.1278 Section 52.1278 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...) Mississippi § 52.1278 Control strategy: Sulfur oxides and particulate matter. (a) In a letter dated January 30...
40 CFR 52.2130 - Control strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy: Sulfur oxides and particulate matter. 52.2130 Section 52.2130 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Carolina § 52.2130 Control strategy: Sulfur oxides and particulate matter. In letters dated May 7, and...
40 CFR 52.2130 - Control strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 5 2012-07-01 2012-07-01 false Control strategy: Sulfur oxides and particulate matter. 52.2130 Section 52.2130 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Carolina § 52.2130 Control strategy: Sulfur oxides and particulate matter. In letters dated May 7, and...
40 CFR 52.2130 - Control strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 5 2014-07-01 2014-07-01 false Control strategy: Sulfur oxides and particulate matter. 52.2130 Section 52.2130 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Carolina § 52.2130 Control strategy: Sulfur oxides and particulate matter. In letters dated May 7, and...
PARTICULATE EMISSION MEASUREMENTS FROM CONTROLLED CONSTRUCTION ACTIVITIES
The report summarized the results of field testing of the effectiveness of control measures for sources of fugitive particulate emissions found at construction sites. The effectiveness of watering temporary, unpaved travel surfaces on emissions of particulate matter with aerodyna...
Parumasivam, Thaigarajan; Chan, John Gar Yan; Lin, Leon C. W.; Flórido, Manuela; West, Nicholas P.; Chan, Hak-Kim; Britton, Warwick J.
2018-01-01
Tuberculosis places a staggering burden on human health globally. The new World Health Organisation End-TB Strategy has highlighted the urgent need for more effective TB vaccines to improve control of the disease. Protein-based subunit vaccines offer potential as safe and effective generators of protective immunity, and the use of particulate vaccine formulation and delivery by the pulmonary route may enhance local immunogenicity. In this study, novel particulate subunit vaccines were developed utilising biodegradable poly(lactic-co-glycolic acid) (PLGA) slow-release particles as carriers for the Mycobacterium tuberculosis lipoprotein MPT83, together with the adjuvants trehalose-dibehenate (TDB) or Monophosphoryl lipid A (MPL). Following delivery by the pulmonary or subcutaneous routes, the immunogenicity and protective efficacy of these vaccines were assessed in a murine model of M. tuberculosis infection. When delivered peripherally, these vaccines induced modest, antigen-specific Th1 and Th17 responses, but strong anti-MPT83 antibody responses. Mucosal delivery of the PLGA(MPT83) vaccine, with or without TDB, increased antigen-specific Th17 responses in the lungs, however, PLGA-encapsulated vaccines did not provide protection against M. tuberculosis challenge. By contrast, peripheral delivery of DDA liposomes containing MPT83 and TDB or MPL, stimulated both Th1 and Th17 responses and generated protection against M. tuberculosis challenge. Therefore, PLGA-formulated vaccines primarily stimulate strong humoral immunity, or Th17 responses if used mucosally, and may be a suitable carrier for vaccines against extracellular pathogens. This study emphasises the critical nature of the vaccine carrier, adjuvant and route of delivery for optimising vaccine efficacy against TB. PMID:29554138
NASA Astrophysics Data System (ADS)
Kumar, Amit; Narayan, Bastola; Pachat, Rohit; Ranjan, Rajeev
2018-02-01
Ferroelectric-ferromagnetic multiferroic composites are of great interest both from the scientific and technological standpoints. The extent of coupling between polarization and magnetization in such two-phase systems depends on how efficiently the magnetostrictive and electrostrictive/piezoelectric strain gets transferred from one phase to the other. This challenge is most profound in the easy to make 0-3 ferroelectric-ferromagnetic particulate composites. Here we report a self-grown ferroelectric-ferromagnetic 0-3 particulate composite through controlled spontaneous precipitation of ferrimagnetic barium hexaferrite phase (BaF e12O19 ) amid ferroelectric grains in the multiferroic alloy system BiFe O3-BaTi O3 . We demonstrate that a composite specimen exhibiting merely ˜1% hexaferrite phase exhibits ˜34% increase in saturation polarization in a dc magnetic field of ˜10 kOe. Using modified Rayleigh analysis of the polarization field loop in the subcoercive field region we argue that the substantial enhancement in the ferroelectric switching is associated with the reduction in the barrier heights of the pinning centers of the ferroelectric-ferroelastic domain walls in the stress field generated by magnetostriction in the hexaferrite grains when the magnetic field is turned on. Our study proves that controlled precipitation of the magnetic phase is a good strategy for synthesis of 0-3 ferroelectric-ferromagnetic particulate multiferroic composite as it not only helps in ensuring a good electrical insulating character of the composite, enabling it to sustain high enough electric field for ferroelectric switching, but also the factors associated with the spontaneity of the precipitation process ensure efficient transfer of the magnetostrictive strain/stress to the surrounding ferroelectric matrix making domain wall motion easy.
NASA Technical Reports Server (NTRS)
Quattrochi, Dale A.; Rickman, Douglas; Mohammad, Al-Hamdan; Crosson, William; Estes, Maurice, Jr.; Limaye, Ashutosh; Qualters, Judith
2008-01-01
Describes the public health surveillance efforts of NASA, in a joint effort with the Center for Disease Control (CDC). NASA/MSFC and the CDC are partners in linking nvironmental and health data to enhance public health surveillance. The use of NASA technology creates value - added geospatial products from existing environmental data sources to facilitate public health linkages. The venture sought to provide remote sensing data for the 5-country Metro-Atlanta area and to integrate this environmental data with public health data into a local network, in an effort to prevent and control environmentally related health effects. Remote sensing data used environmental data (Environmental Protection Agency [EPA] Air Quality System [AQS] ground measurements and MODIS Aerosol Optical Depth [AOD]) to estimate airborne particulate matter over Atlanta, and linked this data with health data related to asthma. The study proved the feasibility of linking environmental data (MODIS particular matter estimates and AQS) with health data (asthma). Algorithms were developed for QC, bias removal, merging MODIS and AQS particulate matter data, as well as for other applications. Additionally, a Business Associate Agreement was negotiated for a health care provider to enable sharing of Protected Health Information.
40 CFR 52.578 - Control Strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 3 2011-07-01 2011-07-01 false Control Strategy: Sulfur oxides and... Strategy: Sulfur oxides and particulate matter. Link to an amendment published at 76 FR 31859, June 2, 2011... user, the added text is set forth as follows: § 52.578 Control Strategy: Sulfur oxides and particulate...
Baek, Jong-Suep; Choo, Chee Chong; Tan, Nguan Soon; Loo, Say Chye Joachim
2017-10-06
Polymeric particulate delivery systems are vastly explored for the delivery of chemotherapeutic agents. However, the preparation of polymeric particulate systems with the capability of providing sustained release of two or more drugs is still a challenge. Herein, poly (D, L-lactic-co-glycolic acid, 50:50) hollow microparticles co-loaded with doxorubicin and paclitaxel were developed through double-emulsion solvent evaporation technique. Hollow microparticles were formed through the addition of an osmolyte into the fabrication process. The benefits of hollow over solid microparticles were found to be higher encapsulation efficiency and a more rapid drug release rate. Further modification of the hollow microparticles was accomplished through the introduction of methyl-β-cyclodextrin. With this, a higher encapsulation efficiency of both drugs and an enhanced cumulative release were achieved. Spheroid study further demonstrated that the controlled release of the drugs from the methyl-β-cyclodextrin -loaded hollow microparticles exhibited enhanced tumor regressions of MCF-7 tumor spheroids. Such hollow dual-drug-loaded hollow microparticles with sustained releasing capabilities may have a potential for future applications in cancer therapy.
Kokate, Rutika A; Thamake, Sanjay I; Chaudhary, Pankaj; Mott, Brittney; Raut, Sangram; Vishwanatha, Jamboor K; Jones, Harlan P
2015-01-01
Low immunogenicity remains a major obstacle in realizing the full potential of cancer vaccines. In this study, we evaluated CpG-coated tumor antigen (Tag)-encapsulating 'bacteriomimetic' nanoparticles (CpG-nanoparticle [NP]-Tag NPs) as an approach to enhance anti-tumor immunity. CpG-NP-Tag NPs were synthesized, characterized for their physicochemical properties and tested in vivo. We found CpG predosing followed by intraperitoneal (IP) immunization with CpG-NP-Tag NPs significantly attenuated tumor growth in female BALB/c mice compared with respective controls. Histopathological and Immunofluorescence data revealed CpG-NP-Tag tumors had lower proliferation, higher apoptotic activity, greater CD4(+) and CD8(+) T cell infiltration as well as higher IFN-γ levels as compared with control groups. Our findings suggest CpG-NP-Tag NPs can enhance anti-tumor effect of nanoparticulate tumor vaccination system.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Reece, Charles E.; Ciancio, Elizabeth J.; Keyes, Katharine A.
2009-11-01
Particulate contamination on the surface of SRF cavities limits their performance via the enhanced generation of field-emitted electrons. Considerable efforts are expended to actively clean and avoid such contamination on niobium surfaces. The protocols in active use have been developed via feedback from cavity testing. This approach has the risk of over-conservatively ratcheting an ever increasing complexity of methods tied to particular circumstances. A complementary and perhaps helpful approach is to quantitatively assess the effectiveness of candidate methods at removing intentional representative particulate contamination. Toward this end, we developed a standardized contamination protocol using water suspensions of Nb{sub 2}O{sub 5}more » and SS 316 powders applied to BCP’d surfaces of standardized niobium samples yielding particle densities of order 200 particles/mm{sup 2}. From these starting conditions, controlled application of high pressure water rinse, ultrasonic cleaning, or CO{sub 2} snow jet cleaning was applied and the resulting surfaces examined via SEM/scanning EDS with particle recognition software. Results of initial parametric variations of each will be reported.« less
Ultrafine ambient particulate matter enhances cardiac ischemia and reperfusion injury
Epidemiological studies have demonstrated a consistent link between exposure to ambient particulate air pollutant (PM) and the incidence of cardiovascular morbidity and mortality. The present study was designed to evaluate the cardiac effects of ambient PM. Mice were exposed to 1...
40 CFR 52.427 - Control strategy: Particulate matter.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 3 2012-07-01 2012-07-01 false Control strategy: Particulate matter. 52.427 Section 52.427 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR...: Particulate matter. Determination of attainment. EPA has determined, as of May 16, 2012, that based on 2007 to...
40 CFR 52.332 - Control strategy: Particulate matter.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 3 2011-07-01 2011-07-01 false Control strategy: Particulate matter. 52.332 Section 52.332 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR...: Particulate matter. (a) On April 9, 1992, the Governor of Colorado submitted the moderate PM-10 nonattainment...
40 CFR 52.332 - Control strategy: Particulate matter.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 3 2014-07-01 2014-07-01 false Control strategy: Particulate matter. 52.332 Section 52.332 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR...: Particulate matter. (a) On April 9, 1992, the Governor of Colorado submitted the moderate PM-10 nonattainment...
40 CFR 52.332 - Control strategy: Particulate matter.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 3 2013-07-01 2013-07-01 false Control strategy: Particulate matter. 52.332 Section 52.332 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR...: Particulate matter. (a) On April 9, 1992, the Governor of Colorado submitted the moderate PM-10 nonattainment...
40 CFR 52.332 - Control strategy: Particulate matter.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 3 2012-07-01 2012-07-01 false Control strategy: Particulate matter. 52.332 Section 52.332 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR...: Particulate matter. (a) On April 9, 1992, the Governor of Colorado submitted the moderate PM-10 nonattainment...
40 CFR 52.332 - Control strategy: Particulate matter.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Control strategy: Particulate matter. 52.332 Section 52.332 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR...: Particulate matter. (a) On April 9, 1992, the Governor of Colorado submitted the moderate PM-10 nonattainment...
40 CFR 52.1880 - Control strategy: Particulate matter.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy: Particulate matter... strategy: Particulate matter. (a) The requirements of subpart G of this chapter are not met because the... matter in the Greater Metropolitan Cleveland Intrastate Region and the Ohio portions of the Northwest...
40 CFR 52.1880 - Control strategy: Particulate matter.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy: Particulate matter... strategy: Particulate matter. (a) The requirements of subpart G of this chapter are not met because the... matter in the Greater Metropolitan Cleveland Intrastate Region and the Ohio portions of the Northwest...
40 CFR 52.1880 - Control strategy: Particulate matter.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 4 2013-07-01 2013-07-01 false Control strategy: Particulate matter... strategy: Particulate matter. (a) The requirements of subpart G of this chapter are not met because the... matter in the Greater Metropolitan Cleveland Intrastate Region and the Ohio portions of the Northwest...
40 CFR 52.1880 - Control strategy: Particulate matter.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 4 2012-07-01 2012-07-01 false Control strategy: Particulate matter... strategy: Particulate matter. (a) The requirements of subpart G of this chapter are not met because the... matter in the Greater Metropolitan Cleveland Intrastate Region and the Ohio portions of the Northwest...
40 CFR 52.933 - Control Strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 3 2011-07-01 2011-07-01 false Control Strategy: Sulfur oxides and particulate matter. 52.933 Section 52.933 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Strategy: Sulfur oxides and particulate matter. (a) In a letter dated March 27, 1987, the Kentucky...
40 CFR 52.578 - Control Strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 3 2012-07-01 2012-07-01 false Control Strategy: Sulfur oxides and particulate matter. 52.578 Section 52.578 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Strategy: Sulfur oxides and particulate matter. In a letter dated March 26, 1987, the Georgia Department of...
40 CFR 52.578 - Control Strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Control Strategy: Sulfur oxides and particulate matter. 52.578 Section 52.578 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Strategy: Sulfur oxides and particulate matter. In a letter dated March 26, 1987, the Georgia Department of...
40 CFR 52.578 - Control Strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 3 2013-07-01 2013-07-01 false Control Strategy: Sulfur oxides and particulate matter. 52.578 Section 52.578 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Strategy: Sulfur oxides and particulate matter. In a letter dated March 26, 1987, the Georgia Department of...
40 CFR 52.933 - Control Strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Control Strategy: Sulfur oxides and particulate matter. 52.933 Section 52.933 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Strategy: Sulfur oxides and particulate matter. In a letter dated March 27, 1987, the Kentucky Department...
40 CFR 52.62 - Control strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Control strategy: Sulfur oxides and particulate matter. 52.62 Section 52.62 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... strategy: Sulfur oxides and particulate matter. In a letter dated May 29, 1987, the Alabama Department of...
40 CFR 52.578 - Control Strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 3 2014-07-01 2014-07-01 false Control Strategy: Sulfur oxides and particulate matter. 52.578 Section 52.578 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Strategy: Sulfur oxides and particulate matter. In a letter dated March 26, 1987, the Georgia Department of...
The role of fly-ash particulate material and oxide catalysts in stone degradation
NASA Astrophysics Data System (ADS)
Hutchinson, A. J.; Johnson, J. B.; Thompson, G. E.; Wood, G. C.; Sage, P. W.; Cooke, M. J.
Studies of fly-ash composition identified the presence of calcium and sulphur, indicating their potential role as sources of calcium sulphate. Residual acidity (particularly for oil fly ash) suggested the possibility of enhanced chemical reaction, and the presence of transition metals, probably as oxides, might accelerate the oxidation of SO 2 to SO 42-. Exposure tests in a laboratory-based rig simulating dry deposition on Portland and Monks Park limestone, either seeded or unseeded with fly-ash particulate material or transition metal oxide catalysts, were carried out using an SO 2-containing environment at 95% r.h. Enhanced sulphation of these seeded limestones due to the above factors was minimal; at high loadings of fly ash, there was even evidence of masking the limestone surface, reducing sulphation. However, pure CaCO 3 powder in the exposure rig showed increases in sulphation when seeded with metal oxide catalysts. Thus the limestones examined contained sufficient inherent catalysts for the oxidation of SO 2 to SO 42- to proceed at such a rate that external catalysts were superfluous. This implies that dissolution rate of SO 2 in moisture films controls the availability of species for reaction with these carbonate-based stones and that fly ash deposited from the atmosphere does not enhance the reaction.
Sensory nerves within the airways can initiate a variety of protective reflexes. We hypothesized that insults such as exposure to antigen and particulate matter (PM) might dysregulate airway sensory nerve function, thereby contributing to enhanced airway inflammation and hyperre...
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 9 2012-07-01 2012-07-01 false How do I monitor the temperature of....15270 How do I monitor the temperature of flue gases at the inlet of my particulate matter control... temperature of the flue gas stream at the inlet of each particulate matter control device. ...
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 9 2013-07-01 2013-07-01 false How do I monitor the temperature of....15270 How do I monitor the temperature of flue gases at the inlet of my particulate matter control... temperature of the flue gas stream at the inlet of each particulate matter control device. ...
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 9 2014-07-01 2014-07-01 false How do I monitor the temperature of....15270 How do I monitor the temperature of flue gases at the inlet of my particulate matter control... temperature of the flue gas stream at the inlet of each particulate matter control device. ...
Estimation of phosphorus flux in rivers during flooding.
Chen, Yen-Chang; Liu, Jih-Hung; Kuo, Jan-Tai; Lin, Cheng-Fang
2013-07-01
Reservoirs in Taiwan are inundated with nutrients that result in algal growth, and thus also reservoir eutrophication. Controlling the phosphorus load has always been the most crucial issue for maintaining reservoir water quality. Numerous agricultural activities, especially the production of tea in riparian areas, are conducted in watersheds in Taiwan. Nutrients from such activities, including phosphorus, are typically flushed into rivers during flooding, when over 90% of the yearly total amount of phosphorous enters reservoirs. Excessive or enhanced soil erosion from rainstorms can dramatically increase the river sediment load and the amount of particulate phosphorus flushed into rivers. When flow rates are high, particulate phosphorus is the dominant form of phosphorus, but sediment and discharge measurements are difficult during flooding, which makes estimating phosphorus flux in rivers difficult. This study determines total amounts of phosphorus transport by measuring flood discharge and phosphorous levels during flooding. Changes in particulate phosphorus, dissolved phosphorus, and their adsorption behavior during a 24-h period are analyzed owing to the fact that the time for particulate phosphorus adsorption and desorption approaching equilibrium is about 16 h. Erosion of the reservoir watershed was caused by adsorption and desorption of suspended solids in the river, a process which can be summarily described using the Lagmuir isotherm. A method for estimating the phosphorus flux in the Daiyujay Creek during Typhoon Bilis in 2006 is presented in this study. Both sediment and phosphorus are affected by the drastic discharge during flooding. Water quality data were collected during two flood events, flood in June 9, 2006 and Typhoon Bilis, to show the concentrations of suspended solids and total phosphorus during floods are much higher than normal stages. Therefore, the drastic changes of total phosphorus, particulate phosphorus, and dissolved phosphorus in rivers during flooding should be monitored to evaluate the loading of phosphorus more precisely. The results show that monitoring and controlling phosphorus transport during flooding can help prevent the eutrophication of a reservoir.
The report discusses EPA's On-Road Diesel Emissions Characterization Facility, which has been collecting real-world gaseous emissions data for the past 6 years. It has recently undergone extensive modifications to enhance its particulate matter (PM) measurement capabilities, with...
40 CFR 52.528 - Control strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 3 2011-07-01 2011-07-01 false Control strategy: Sulfur oxides and... strategy: Sulfur oxides and particulate matter. (a) In a letter dated October 10, 1986, the Florida... sulfur dioxide in the Everglades National Park. These plants must meet the 0.1#/MMBTU particulate limit...
40 CFR 52.528 - Control strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 3 2014-07-01 2014-07-01 false Control strategy: Sulfur oxides and... strategy: Sulfur oxides and particulate matter. (a) In a letter dated October 10, 1986, the Florida... sulfur dioxide in the Everglades National Park. These plants must meet the 0.1#/MMBTU particulate limit...
40 CFR 52.528 - Control strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 3 2013-07-01 2013-07-01 false Control strategy: Sulfur oxides and... strategy: Sulfur oxides and particulate matter. (a) In a letter dated October 10, 1986, the Florida... sulfur dioxide in the Everglades National Park. These plants must meet the 0.1#/MMBTU particulate limit...
40 CFR 52.528 - Control strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 3 2012-07-01 2012-07-01 false Control strategy: Sulfur oxides and... strategy: Sulfur oxides and particulate matter. (a) In a letter dated October 10, 1986, the Florida... sulfur dioxide in the Everglades National Park. These plants must meet the 0.1#/MMBTU particulate limit...
40 CFR 52.528 - Control strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Control strategy: Sulfur oxides and... strategy: Sulfur oxides and particulate matter. (a) In a letter dated October 10, 1986, the Florida... sulfur dioxide in the Everglades National Park. These plants must meet the 0.1#/MMBTU particulate limit...
McClellan, Roger O; Hesterberg, Thomas W; Wall, John C
2012-07-01
Diesel engines, a special type of internal combustion engine, use heat of compression, rather than electric spark, to ignite hydrocarbon fuels injected into the combustion chamber. Diesel engines have high thermal efficiency and thus, high fuel efficiency. They are widely used in commerce prompting continuous improvement in diesel engines and fuels. Concern for health effects from exposure to diesel exhaust arose in the mid-1900s and stimulated development of emissions regulations and research to improve the technology and characterize potential health hazards. This included epidemiological, controlled human exposure, laboratory animal and mechanistic studies to evaluate potential hazards of whole diesel exhaust. The International Agency for Research on Cancer (1989) classified whole diesel exhaust as - "probably carcinogenic to humans". This classification stimulated even more stringent regulations for particulate matter that required further technological developments. These included improved engine control, improved fuel injection system, enhanced exhaust cooling, use of ultra low sulfur fuel, wall-flow high-efficiency exhaust particulate filters, exhaust catalysts, and crankcase ventilation filtration. The composition of New Technology Diesel Exhaust (NTDE) is qualitatively different and the concentrations of particulate constituents are more than 90% lower than for Traditional Diesel Exhaust (TDE). We recommend that future reviews of carcinogenic hazards of diesel exhaust evaluate NTDE separately from TDE. Copyright © 2012 Elsevier Inc. All rights reserved.
Flue gas desulfurization method and apparatus
Madden, Deborah A.; Farthing, George A.
1998-08-18
A combined furnace limestone injection and dry scrubber flue gas desulfurization (FGD) system collects solids from the flue gas stream in first particulate collection device located downstream of an outlet of a convection pass of the furnace and upstream of the dry scrubber. The collected solids are diverted to the dry scrubber feed slurry preparation system to increase sulfur oxide species removal efficiency and sorbent utilization. The level of lime in the feed slurry provided to the dry scrubber is thus increased, which enhances removal of sulfur oxide species in the dry scrubber. The decreased particulate loading to the dry scrubber helps maintain a desired degree of free moisture in the flue gas stream entering the dry scrubber, which enhances sulfur oxide species removal both in the dry scrubber and downstream particulate collector, normally a baghouse.
Flue gas desulfurization method and apparatus
Madden, Deborah A.; Farthing, George A.
1998-09-29
A combined furnace limestone injection and dry scrubber flue gas desulfurization (FGD) system collects solids from the flue gas stream in first particulate collection device located downstream of an outlet of a convection pass of the furnace and upstream of the dry scrubber. The collected solids are diverted to the dry scrubber feed slurry preparation system to increase sulfur oxide species removal efficiency and sorbent utilization. The level of lime in the feed slurry provided to the dry scrubber is thus increased, which enhances removal of sulfur oxide species in the dry scrubber. The decreased particulate loading to the dry scrubber helps maintain a desired degree of free moisture in the flue gas stream entering the dry scrubber, which enhances sulfur oxide species removal both in the dry scrubber and downstream particulate collector, normally a baghouse.
Akaoka, K; McKendry, I; Saxton, J; Cottle, P W
2017-04-01
Transport of coal by train through residential neighborhoods in Metro Vancouver, British Columbia, Canada may increase the possibility of exposure to particulate matter at different size ranges, with concomitant potential negative health impacts. This pilot study identifies and quantifies train impacts on particulate matter (PM) concentrations at a single location. Field work was conducted during August and September 2014, with the attributes of a subset of passing trains confirmed visually, and the majority of passages identified with audio data. In addition to fixed ground based monitors at distances 15 and 50 m from the train tracks, an horizontally pointing mini-micropulse lidar system was deployed on three days to make backscatter and depolarization measurements in an attempt to identify the zone of influence, and sources, of train-generated PM. Ancillary wind and dust fall data were also utilized. Trains carrying coal are associated with a 5.3 (54%), 4.1 (33%), and 2.6 (17%) μgm -3 average increase in concentration over a 14 min period compared to the average concentrations over the 10 min prior to and after a train passage ("control" or "background" conditions), for PM 3 , PM 10 , and PM 20 , respectively. In addition, for PM 10 and PM 20 , concentrations during train passages of non-coal-carrying trains were not found to be significantly different from PM concentrations during control conditions. Presence of coal dust particles at the site was confirmed by dust fall measurements. Although enhancements of PM concentrations during 14 min train passages were generally modest, passing coal trains occasionally enhanced concentrations at 50 m from the tracks by ∼100 μgm -3 . Results showed that not every train passage increased PM concentrations, and the effect appears to be highly dependent on wind direction, local meteorology and load related factors. LiDAR imagery suggests that re-mobilization of track-side PM by train-induced turbulence may be a significant contributor to coarse particle enhancements. Copyright © 2017 Elsevier Ltd. All rights reserved.
30 CFR 57.5066 - Maintenance standards.
Code of Federal Regulations, 2010 CFR
2010-07-01
..., Physical Agents, and Diesel Particulate Matter Diesel Particulate Matter-Underground Only § 57.5066... manufacturer specifications; and (3) The operator must maintain any emission or particulate control device...
30 CFR 57.5066 - Maintenance standards.
Code of Federal Regulations, 2011 CFR
2011-07-01
..., Physical Agents, and Diesel Particulate Matter Diesel Particulate Matter-Underground Only § 57.5066... manufacturer specifications; and (3) The operator must maintain any emission or particulate control device...
40 CFR 52.228 - Regulations: Particulate matter, Southeast Desert Intrastate Region.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Regulations: Particulate matter... § 52.228 Regulations: Particulate matter, Southeast Desert Intrastate Region. (a) The following... particulate matter in the Southeast Desert Intrastate Region. (1) Imperial County Air Pollution Control...
40 CFR 52.228 - Regulations: Particulate matter, Southeast Desert Intrastate Region.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 3 2011-07-01 2011-07-01 false Regulations: Particulate matter... § 52.228 Regulations: Particulate matter, Southeast Desert Intrastate Region. (a) The following... particulate matter in the Southeast Desert Intrastate Region. (1) Imperial County Air Pollution Control...
Zheng, Clark Renjun; Li, Shuai; Ye, Chengsong; Li, Xinyang; Zhang, Chiqian; Yu, Xin
2016-07-05
Particulate respirators designed to filtrate fine particulate matters usually do not possess antimicrobial functions. The current study aimed to functionalize particulate respirators with silver nanoparticles (nanosilver or AgNPs), which have excellent antimicrobial activities, utilizing a straightforward and effective method. We first enhanced the nanosilver-coating ability of nonwoven fabrics from a particulate respirator through surface modification by sodium oleate. The surfactant treatment significantly improved the fabrics' water wet preference where the static water contact angles reduced from 122° to 56°. Both macroscopic agar-plate tests and microscopic scanning electron microscope (SEM) characterization revealed that nanosilver functionalized fabrics could effectively inhibit the growth of two model bacterial strains (i.e., Staphylococcus aureus and Pseudomonas aeruginosa). The coating of silver nanoparticles would not affect the main function of particulate respirators (i.e., filtration of fine air-borne particles). Nanosilver coated particulate respirators with excellent antimicrobial activities can provide real-time protection to people in regions with severe air pollution against air-borne pathogens.
Pulse combusted acoustic agglomeration apparatus and process
Mansour, Momtaz N.
1993-01-01
An improved apparatus and process for removal of particulates entrained in a gas stream are provided. The removal process employs a pulse combustor to provide an acoustic pressure wave to acoustically enhance bimodal agglomeration of particulates which may be collected and removed using a conventional separation apparatus. A particulate having a size different from the size of the particulate in the gas stream to be cleaned is introduced into the system to effectuate the bimodal process. The apparatus may be employed as a direct fired system for improved operation of gas-operated equipment such as a gas turbine, or may, alternatively, be employed as an add-on subsystem for combustion exhaust clean-up. Additionally, the added particulate may be a sorbent for effecting sorption of other contaminants such as sulfur. Various other particulates for contaminant removal may also be introduced into the system as exemplified by alkali-gettering agents.
High particulate iron(II) content in glacially sourced dusts enhances productivity of a model diatom
Shoenfelt, Elizabeth M.; Sun, Jing; Winckler, Gisela; Kaplan, Michael R.; Borunda, Alejandra L.; Farrell, Kayla R.; Moreno, Patricio I.; Gaiero, Diego M.; Recasens, Cristina; Sambrotto, Raymond N.; Bostick, Benjamin C.
2017-01-01
Little is known about the bioavailability of iron (Fe) in natural dusts and the impact of dust mineralogy on Fe utilization by photosynthetic organisms. Variation in the supply of bioavailable Fe to the ocean has the potential to influence the global carbon cycle by modulating primary production in the Southern Ocean. Much of the dust deposited across the Southern Ocean is sourced from South America, particularly Patagonia, where the waxing and waning of past and present glaciers generate fresh glaciogenic material that contrasts with aged and chemically weathered nonglaciogenic sediments. We show that these two potential sources of modern-day dust are mineralogically distinct, where glaciogenic dust sources contain mostly Fe(II)-rich primary silicate minerals, and nearby nonglaciogenic dust sources contain mostly Fe(III)-rich oxyhydroxide and Fe(III) silicate weathering products. In laboratory culture experiments, Phaeodactylum tricornutum, a well-studied coastal model diatom, grows more rapidly, and with higher photosynthetic efficiency, with input of glaciogenic particulates compared to that of nonglaciogenic particulates due to these differences in Fe mineralogy. Monod nutrient accessibility models fit to our data suggest that particulate Fe(II) content, rather than abiotic solubility, controls the Fe bioavailability in our Fe fertilization experiments. Thus, it is possible for this diatom to access particulate Fe in dusts by another mechanism besides uptake of unchelated Fe (Fe′) dissolved from particles into the bulk solution. If this capability is widespread in the Southern Ocean, then dusts deposited to the Southern Ocean in cold glacial periods are likely more bioavailable than those deposited in warm interglacial periods. PMID:28691098
40 CFR 52.126 - Control strategy and regulations: Particulate matter.
Code of Federal Regulations, 2011 CFR
2011-07-01
...: Particulate matter. 52.126 Section 52.126 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... strategy and regulations: Particulate matter. (a) The requirements of subpart G and § 51.281 of this... the national standards for particulate matter in Gila, Maricopa, Pima, Pinal, and Santa Cruz Counties...
Kim, Jeong Tae; Barua, Sonia; Kim, Hyeongmin; Hong, Seong-Chul; Yoo, Seung-Yup; Jeon, Hyojin; Cho, Yeongjin; Gil, Sangwon; Oh, Kyungsoo; Lee, Jaehwi
2017-07-01
In this study, the effect of particle size of genistein-loaded solid lipid particulate systems on drug dissolution behavior and oral bioavailability was investigated. Genistein-loaded solid lipid microparticles and nanoparticles were prepared with glyceryl palmitostearate. Except for the particle size, other properties of genistein-loaded solid lipid microparticles and nanoparticles such as particle composition and drug loading efficiency and amount were similarly controlled to mainly evaluate the effect of different particle sizes of the solid lipid particulate systems on drug dissolution behavior and oral bioavailability. The results showed that genistein-loaded solid lipid microparticles and nanoparticles exhibited a considerably increased drug dissolution rate compared to that of genistein bulk powder and suspension. The microparticles gradually released genistein as a function of time while the nanoparticles exhibited a biphasic drug release pattern, showing an initial burst drug release, followed by a sustained release. The oral bioavailability of genistein loaded in solid lipid microparticles and nanoparticles in rats was also significantly enhanced compared to that in bulk powders and the suspension. However, the bioavailability from the microparticles increased more than that from the nanoparticles mainly because the rapid drug dissolution rate and rapid absorption of genistein because of the large surface area of the genistein-solid lipid nanoparticles cleared the drug to a greater extent than the genistein-solid lipid microparticles did. Therefore, the findings of this study suggest that controlling the particle size of solid-lipid particulate systems at a micro-scale would be a promising strategy to increase the oral bioavailability of genistein.
40 CFR 52.1781 - Control strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 4 2013-07-01 2013-07-01 false Control strategy: Sulfur oxides and... Carolina § 52.1781 Control strategy: Sulfur oxides and particulate matter. (a) The plan's control strategy... State expects the resulting emission reductions of nitrogen oxides and sulfur dioxide from this control...
40 CFR 52.1781 - Control strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 4 2014-07-01 2014-07-01 false Control strategy: Sulfur oxides and... Carolina § 52.1781 Control strategy: Sulfur oxides and particulate matter. (a) The plan's control strategy... State expects the resulting emission reductions of nitrogen oxides and sulfur dioxide from this control...
40 CFR 52.1781 - Control strategy: Sulfur oxides and particulate matter.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 4 2012-07-01 2012-07-01 false Control strategy: Sulfur oxides and... Carolina § 52.1781 Control strategy: Sulfur oxides and particulate matter. (a) The plan's control strategy... State expects the resulting emission reductions of nitrogen oxides and sulfur dioxide from this control...
Liu, Min; Luo, Fengling; Ding, Chuanlin; Albeituni, Sabrin; Hu, Xiaoling; Ma, Yunfeng; Cai, Yihua; McNally, Lacey; Sanders, Mary Ann; Jain, Dharamvir; Kloecker, Goetz; Bousamra, Michael; Zhang, Huang-ge; Higashi, Richard M.; Lane, Andrew N.; Fan, Teresa W-M.; Yan, Jun
2015-01-01
Tumor-associated macrophages (TAM) with an M2-like phenotype have been linked to tumor-elicited inflammation, immunosuppression, and resistance to chemotherapies in cancer, thus representing an attractive target for an effective cancer immunotherapy. Here, we demonstrate that particulate yeast-derived β-glucan, a natural polysaccharide compound, converts polarized M2 macrophages or immunosuppressive TAM into an M1-like phenotype with potent immuno-stimulating activity. This process is associated with macrophage metabolic reprograming with enhanced glycolysis, krebs cycle and glutamine utilization. In addition, particulate β-glucan converts immunosuppressive TAM via the C-type lectin receptor dectin-1-induced Syk-Card9-Erk pathway. Further in vivo studies show that oral particulate β-glucan treatment significantly delays tumor growth, which is associated with in vivo TAM phenotype conversion and enhanced effector T cell activation. Mice injected with particulate β-glucan-treated TAM mixed with tumor cells have significantly reduced tumor burden with less blood vascular vessels compared to those with TAM plus tumor cell injection. In addition, macrophage depletion significantly reduced the therapeutic efficacy of particulate β-glucan in tumor-bearing mice. These findings have established a new paradigm for macrophage polarization and immunosuppressive TAM conversion and shed the light on the action mode of β-glucan treatment in cancer. PMID:26453753
Control Techniques for Particulate Air Pollutants.
ERIC Educational Resources Information Center
National Air Pollution Control Administration (DHEW), Washington, DC.
Included is a comprehensive review of the approaches commonly recommended for controlling the sources of particulate air pollution. Not all possible combinations of control techniques that might bring about more stringent control of each individual source are reviewed. The many agricultural, commercial, domestic, industrial, and municipal…
Liberda, Eric N; Tsuji, Leonard J S; Peltier, Richard E
2015-11-01
Airborne particulate matter arising from upwind mining activities is a concern for First Nations communities in the western James Bay region of Ontario, Canada. Aerosol chemical components were collected in 2011 from two communities in northern Ontario. The chemical and mass concentration data of particulate matter collected during this study shows a significant difference in PM2.5 in Attawapiskat compared to Fort Albany. Elemental profiles indicate enhanced levels of some tracers thought to arise from mining activities, such as, K, Ni, and crustal materials. Both communities are remote and isolated from urban and industrial pollution sources, however, Attawapiskat First Nation has significantly enhanced levels of particulate matter, and it is likely that some of this arises from upwind mining activities. Copyright © 2015 Elsevier Ltd. All rights reserved.
Flue gas desulfurization method and apparatus
Madden, D.A.; Farthing, G.A.
1998-08-18
A combined furnace limestone injection and dry scrubber flue gas desulfurization (FGD) system collects solids from the flue gas stream in first particulate collection device located downstream of an outlet of a convection pass of the furnace and upstream of the dry scrubber. The collected solids are diverted to the dry scrubber feed slurry preparation system to increase sulfur oxide species removal efficiency and sorbent utilization. The level of lime in the feed slurry provided to the dry scrubber is thus increased, which enhances removal of sulfur oxide species in the dry scrubber. The decreased particulate loading to the dry scrubber helps maintain a desired degree of free moisture in the flue gas stream entering the dry scrubber, which enhances sulfur oxide species removal both in the dry scrubber and downstream particulate collector, normally a baghouse. 5 figs.
Flue gas desulfurization method and apparatus
Madden, D.A.; Farthing, G.A.
1998-09-29
A combined furnace limestone injection and dry scrubber flue gas desulfurization (FGD) system collects solids from the flue gas stream in first particulate collection device located downstream of an outlet of a convection pass of the furnace and upstream of the dry scrubber. The collected solids are diverted to the dry scrubber feed slurry preparation system to increase sulfur oxide species removal efficiency and sorbent utilization. The level of lime in the feed slurry provided to the dry scrubber is thus increased, which enhances removal of sulfur oxide species in the dry scrubber. The decreased particulate loading to the dry scrubber helps maintain a desired degree of free moisture in the flue gas stream entering the dry scrubber, which enhances sulfur oxide species removal both in the dry scrubber and downstream particulate collector, normally a baghouse. 5 figs.
Communities near major roadways are disproportionately affected by traffic-related air pollution which can contribute to adverse health outcomes. The specific role of particulate matter (PM) from traffic sources is not fully understood due to complex emissions processes and physi...
Tunable geometry of bacterial inclusion bodies as substrate materials for tissue engineering
NASA Astrophysics Data System (ADS)
García-Fruitós, Elena; Seras-Franzoso, Joaquín; Vazquez, Esther; Villaverde, Antonio
2010-05-01
A spectrum of materials for biomedical applications is produced in bacteria, and some of them, such as metals or polyhydroxyalkanoates, are straightforwardly obtained as particulate entities. We have explored the biofabrication process of bacterial inclusion bodies, particulate proteinaceous materials (ranging from 50 to 500 nm in diameter) recently recognized as suitable for surface topographical modification and tissue engineering. Inclusion bodies have been widely described as spherical or pseudo-spherical particles with only minor morphological variability, mostly restricted to their size. Here we have identified a cellular gene in Escherichia coli (clpP) that controls the in vivo fabrication process of inclusion bodies. In the absence of the encoded protease, the dynamics of protein deposition is perturbed, resulting in unusual tear-shaped particles with enhanced surface-volume ratios. This fact modifies the ability of inclusion bodies to promote mammalian cell attachment and differentiation upon surface decoration. The implications of the genetic control of inclusion body geometry are discussed in the context of their biological fabrication and regarding the biomedical potential of these protein clusters in regenerative medicine.
Event-driven sediment flux in Hueneme and Mugu submarine canyons, southern California
Xu, J. P.; Swarzenski, P.W.; Noble, M.; Li, A.-C.
2010-01-01
Vertical sediment fluxes and their dominant controlling processes in Hueneme and Mugu submarine canyons off south-central California were assessed using data from sediment traps and current meters on two moorings that were deployed for 6 months during the winter of 2007. The maxima of total particulate flux, which reached as high as 300+ g/m2/day in Hueneme Canyon, were recorded during winter storm events when high waves and river floods often coincided. During these winter storms, wave-induced resuspension of shelf sediment was a major source for the elevated sediment fluxes. Canyon rim morphology, rather than physical proximity to an adjacent river mouth, appeared to control the magnitude of sediment fluxes in these two submarine canyon systems. Episodic turbidity currents and internal bores enhanced sediment fluxes, particularly in the lower sediment traps positioned 30 m above the canyon floor. Lower excess 210Pb activities measured in the sediment samples collected during periods of peak total particulate flux further substantiate that reworked shelf-, rather than newly introduced river-borne, sediments supply most of the material entering these canyons during storms.
EMAT enhanced dispersion of particles in liquid
Kisner, Roger A.; Rios, Orlando; Melin, Alexander M.; Ludtka, Gerard Michael; Ludtka, Gail Mackiewicz; Wilgen, John B.
2016-11-29
Particulate matter is dispersed in a fluid material. A sample including a first material in a fluid state and second material comprising particulate matter are placed into a chamber. The second material is spatially dispersed in the first material utilizing EMAT force. The dispersion process continues until spatial distribution of the second material enables the sample to meet a specified criterion. The chamber and/or the sample is electrically conductive. The EMAT force is generated by placing the chamber coaxially within an induction coil driven by an applied alternating current and placing the chamber and induction coil coaxially within a high field magnetic. The EMAT force is coupled to the sample without physical contact to the sample or to the chamber, by another physical object. Batch and continuous processing are utilized. The chamber may be folded within the bore of the magnet. Acoustic force frequency and/or temperature may be controlled.
Otaigbe, Joshua U.; McAvoy, Jon M.; Anderson, Iver E.; Ting, Jason; Mi, Jia; Terpstra, Robert
2001-01-09
Method for making polymer particulates, such as spherical powder and whiskers, by melting a polymer material under conditions to avoid thermal degradation of the polymer material, atomizing the melt using gas jet means in a manner to form atomized droplets, and cooling the droplets to form polymer particulates, which are collected for further processing. Atomization parameters can be controlled to produce polymer particulates with controlled particle shape, particle size, and particle size distribution. For example, atomization parameters can be controlled to produce spherical polymer powders, polymer whiskers, and combinations of spherical powders and whiskers. Atomizing apparatus also is provided for atoomizing polymer and metallic materials.
NASA Astrophysics Data System (ADS)
Li, Zhen; Jiang, Jingkun; Ma, Zizhen; Wang, Shuxiao; Duan, Lei
2015-11-01
Nitrogen oxides (NOx) emission abatement of coal-fired power plants (CFPPs) requires large-scaled installation of selective catalytic reduction (SCR), which would reduce secondary fine particulate matter (PM2.5) (by reducing nitrate aerosol) in the atmosphere. However, our field measurement of two CFPPs equipped with SCR indicates a significant increase of SO42- and NH4+ emission in primary PM2.5, due to catalytic enhancement of SO2 oxidation to SO3 and introducing of NH3 as reducing agent. The subsequent formation of (NH4)2SO4 or NH4HSO4 aerosol is commonly concentrated in sub-micrometer particulate matter (PM1) with a bimodal pattern. The measurement at the inlet of stack also showed doubled primary PM2.5 emission by SCR operation. This effect should therefore be considered when updating emission inventory of CFPPs. By rough estimation, the enhanced primary PM2.5 emission from CFPPs by SCR operation would offset 12% of the ambient PM2.5 concentration reduction in cities as the benefit of national NOx emission abatement, which should draw attention of policy-makers for air pollution control.
Zhu, Y H; Wu, R; Zhong, P R; Zhu, C H; Ma, L
2016-06-01
To analyze the temperature modification effect on acute mortality due to particulate air pollution. Daily non-accidental mortality, cardiovascular mortality, and respiratory mortality data were obtained from Jiang'an District Center for Disease Control and Prevention. Daily meteorological data on mean temperature and relative humidity were collected from China Meteorological Data Sharing Service System. The daily concentration of particulate matter was collected from Wuhan Environmental Monitoring center. By using the stratified time-series models, we analyzed effects of particulate air pollution on mortality under different temperature zone from 2002 to 2010, meanwhile comparing the difference of age, gender and educational level, in Wuhan city of China. High temperature (daily average temperature > 33.4 ℃) obviously enhanced the effect of PM10 on mortality. With 10 μg/m(3) increase in PM10 concentrations, non-accidental, cardiovascular, and respiratory mortality increased 2.95% (95%CI: 1.68%-4.24%), 3.58% (95%CI: 1.72%-5.49%), and 5.07% (95%CI: 2.03%-9.51%) respectively. However, low temperature (daily average temperature <-0.21 ℃) enhanced PM10 effect on respiratory mortality with 3.31% (95% CI: 0.07%-6.64%) increase. At high temperature, PM10 had significantly stronger effect on non-accidental mortality of female aged over 65 and people with high educational level groups. With an increase of 10 μg/m(3), daily non-accidental mortality increased 4.27% (95% CI:2.45%-6.12%), 3.38% (95% CI:1.93%-4.86%) and 3.47% (95% CI:1.79%-5.18%), respectively. Whereas people with low educational level were more susceptible to low temperature. A 10 μg/m(3) increase in PM10 was associated with 2.11% (95% CI: 0.20%-4.04%) for non-accidental mortality. Temperature factor can modify the association between the PM10 level and cause-specific mortality. Moreover, the differences were apparent after considering the age, gender and education groups.
Thevenot, Paul; Saravia, Jordy; Giaimo, Joseph; Happel, Kyle I.; Dugas, Tammy R.; Cormier, Stephania A.
2013-01-01
Background Chronic alcohol consumption causes persistent oxidative stress in the lung, leading to impaired alveolar macrophage (AM) function and impaired immune responses. AMs play a critical role in protecting the lung from particulate matter (PM) inhalation by removing particulates from the airway and secreting factors which mediate airway repair. We hypothesized AM dysfunction caused by chronic alcohol consumption increases the severity of injury caused by particulate matter inhalation. Methods Age- and sex-matched C57BL6 mice were fed the Lieber-DeCarli liquid diet containing either alcohol or an iso-caloric substitution (control diet) for 8 weeks. Mice from both diet groups were exposed to combustion derived PM (CDPM) for the final 2 weeks. AM number, maturation, and polarization status were assessed by flow cytometry. Noninvasive and invasive strategies were used to assess pulmonary function and correlated with histomorphological assessments of airway structure and matrix deposition. Results Co-exposure to alcohol and CDPM decreased AM number and maturation status (CD11c expression) while increasing markers of M2 activation (IL-4Rα, Ym1, Fizz1 expression and IL-10 and TGF-β production). Changes in AM function were accompanied by decreased airway compliance and increased elastance. Altered lung function was attributable to elevated collagen content localized to the small airways and loss of alveolar integrity. Intranasal administration of neutralizing antibody to TGF-β during the CDPM exposure period improved changes in airway compliance and elastance while reducing collagen content caused by co-exposure. Conclusion CDPM inhalation causes enhanced disease severity in the alcoholic lung by stimulating the release of latent TGF-β stores in AMs. The combinatorial effect of elevated TGF-β, M2 polarization of AMs, and increased oxidative stress impairs pulmonary function by increasing airway collagen content and compromising alveolar integrity. PMID:23763452
Pulse combusted acoustic agglomeration apparatus and process
Mansour, Momtaz N.; Chandran, Ravi
1994-01-01
An improved apparatus and process for removal of particulates entrained in a gas stream are provided. The removal process employs a pulse combustor to provide an acoustic pressure wave to acoustically enhance agglomeration of particulates which may be collected and removed using a conventional separation apparatus. The apparatus may be employed as a direct fired system for improved operation of gas-operated equipment such as a gas turbine, or may, alternatively, be employed as an add-on subsystem for combustion exhaust clean-up. Additionally, added particulates may include a sorbent for effecting sorption of other contaminants such as sulfur. Various other particulates for contaminant removal may also be introduced into the system as exemplified by alkali-gettering agents.
40 CFR 60.262 - Standard for particulate matter.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for particulate matter. 60.262... Production Facilities § 60.262 Standard for particulate matter. (a) On and after the date on which the... furnace any gases which: (1) Exit from a control device and contain particulate matter in excess of 0.45...
40 CFR 60.262 - Standard for particulate matter.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standard for particulate matter. 60.262... Production Facilities § 60.262 Standard for particulate matter. (a) On and after the date on which the... furnace any gases which: (1) Exit from a control device and contain particulate matter in excess of 0.45...
40 CFR 60.262 - Standard for particulate matter.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for particulate matter. 60.262... Production Facilities § 60.262 Standard for particulate matter. (a) On and after the date on which the... furnace any gases which: (1) Exit from a control device and contain particulate matter in excess of 0.45...
40 CFR 60.262 - Standard for particulate matter.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standard for particulate matter. 60.262... Production Facilities § 60.262 Standard for particulate matter. (a) On and after the date on which the... furnace any gases which: (1) Exit from a control device and contain particulate matter in excess of 0.45...
Removal of residual particulate matter from filter media
DOE Office of Scientific and Technical Information (OSTI.GOV)
Almlie, Jay C.; Miller, Stanley J.
A method for removing residual filter cakes that remain adhered to a filter after typical particulate removal methodologies have been employed, such as pulse-jet filter element cleaning, for all cleanable filters used for air pollution control, dust control, or powder control.
Removal of residual particulate matter from filter media
Almlie, Jay C; Miller, Stanley J
2014-11-11
A method for removing residual filter cakes that remain adhered to a filter after typical particulate removal methodologies have been employed, such as pulse-jet filter element cleaning, for all cleanable filters used for air pollution control, dust control, or powder control.
Allergic susceptibility associated with diesel exhaust particle exposure: clear as mud.
Polosa, Riccardo; Salvi, Sundeep; Di Maria, Giuseppe U
2002-01-01
Exposure to elevated levels of particulate air pollution from motor vehicles is frequently associated with increased morbidity and mortality from cardiovascular conditions, lung cancer, and nonmalignant respiratory illnesses (e.g., asthma, bronchitis, respiratory tract infections). It appears, however, that less attention has been paid to the potential role of road traffic fumes in the induction of allergic conditions. Laboratory studies in humans and animals have shown that particulate toxic pollutants-particularly diesel exhaust particulates-can enhance allergic inflammation and can induce allergic immune responses. Most of these immune responses are mediated by the carbon core of diesel exhaust particulates. Polyaromatic hydrocarbons (e.g., anthracene, fluoranthene, pyrene, phenanthrene) are major chemical components of diesel exhaust particulates, and they have enhanced the production of immunoglobulin E. Although several large epidemiological studies have demonstrated a strong association between exposure to motor vehicle traffic emissions and allergic symptoms and reduced lung function, the evidence for the development of allergic sensitization from diesel exhaust particulates is less abundant than for the aforementioned associations. Recent comparisons of the prevalence of hay fever, as well as positive skin-prick tests, between citizens of former West and East Germany and between Hong Kong and China civilians, have demonstrated marked differences. Crucial variations in the level of particulate air pollution from motor vehicles in these countries may account for the observed increased prevalence of atopy. Although road-traffic pollution from automobile exhausts may be a risk factor for atopic sensitization, the evidence in support of this view remains conflictive. Some investigators have reported a clear association between the prevalence of allergy and road-traffic-related air pollution, whereas such a difference was not observed in other studies. Most discrepancies have been related to important variations in study design and methodology. In addition, inasmuch as exposure to ambient particles differs substantially in worldwide urban environments, perhaps qualitative-rather than quantitative-variations in particulate air pollution at different locations account for differences in the prevalence and/or severity of respiratory allergies.
NASA Astrophysics Data System (ADS)
Noh, Seam; Choi, Mijin; Kim, Eunhee; Dan, Nguyen Phuoc; Thanh, Bui Xuan; Ha, Nguyen Thi Van; Sthiannopkao, Suthipong; Han, Seunghee
2013-04-01
The lower Mekong and Saigon River Basins are dominated by distinctive monsoon seasons, dry and rainy seasons. Most of the Mekong River is a freshwater region during the rainy season, whereas during the dry season, salt water intrudes approximately 70 km inland. To understand the role of salinity intrusion controlling Hg behavior in the Mekong and Saigon River Basins, Hg and monomethylmercury (MMHg) in surface water and sediment of the Mekong River and in sediment of the Saigon River were investigated in the dry season. Sediment Hg distribution, ranging from 0.12 to 0.76 nmol g-1, was mainly controlled by organic carbon distribution in the Mekong River; however, the location of point sources was more important in the Saigon River (0.21-0.65 nmol g-1). The MMHg concentrations in Mekong (0.16-6.1 pmol g-1) and Saigon (0.70-8.7 pmol g-1) sediment typically showed significant increases in the estuarine head, with sharp increases of acid volatile sulfide. Unfiltered Hg (4.6-222 pM) and filtered Hg (1.2-14 pM) in the Mekong River increased in the estuarine zone due to enhanced particle loads. Conversely, unfiltered MMHg (0.056-0.39 pM) and filtered MMHg (0.020-0.17 pM) was similar between freshwater and estuarine zones, which was associated with mixing dilution of particulate MMHg by organic- and MMHg-depleted resuspended sediment. Partitioning of Hg between water and suspended particle showed tight correlation with the partitioning of organic carbon across study sites, while that of MMHg implied influences of chloride: enhanced chloride in addition to organic matter depletion decreased particulate MMHg in the estuarine zone. Primary production was an important determinant of inter-annual variation of particulate Hg and sediment MMHg. The bloom year showed relatively low particulate Hg with low C/N ratio, indicating biodilution of Hg. In contrast, the percentage of MMHg in sediment increased significantly in the bloom year, likely due to greater availability of metabolizable fresh organic matter. The overall results emphasize that Hg behavior in the lower Mekong River Basin is strongly connected to the local monsoon climate, via alterations in particle loads, biological productivity, and availability of sulfate, chloride and organic matter.
40 CFR 60.272a - Standard for particulate matter.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for particulate matter. 60... Standard for particulate matter. (a) On and after the date of which the performance test required to be... control device and contain particulate matter in excess of 12 mg/dscm (0.0052 gr/dscf); (2) Exit from a...
40 CFR 60.272a - Standard for particulate matter.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standard for particulate matter. 60... Standard for particulate matter. (a) On and after the date of which the performance test required to be... control device and contain particulate matter in excess of 12 mg/dscm (0.0052 gr/dscf); (2) Exit from a...
40 CFR 60.272 - Standard for particulate matter.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standard for particulate matter. 60.272... Standard for particulate matter. (a) On and after the date on which the performance test required to be... control device and contain particulate matter in excess of 12 mg/dscm (0.0052 gr/dscf). (2) Exit from a...
40 CFR 60.272a - Standard for particulate matter.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for particulate matter. 60... Standard for particulate matter. (a) On and after the date of which the performance test required to be... control device and contain particulate matter in excess of 12 mg/dscm (0.0052 gr/dscf); (2) Exit from a...
40 CFR 60.272 - Standard for particulate matter.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for particulate matter. 60.272... Standard for particulate matter. (a) On and after the date on which the performance test required to be... control device and contain particulate matter in excess of 12 mg/dscm (0.0052 gr/dscf). (2) Exit from a...
40 CFR 60.272a - Standard for particulate matter.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for particulate matter. 60... Standard for particulate matter. (a) On and after the date of which the performance test required to be... control device and contain particulate matter in excess of 12 mg/dscm (0.0052 gr/dscf); (2) Exit from a...
40 CFR 60.272 - Standard for particulate matter.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for particulate matter. 60.272... Standard for particulate matter. (a) On and after the date on which the performance test required to be... control device and contain particulate matter in excess of 12 mg/dscm (0.0052 gr/dscf). (2) Exit from a...
40 CFR 60.272a - Standard for particulate matter.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standard for particulate matter. 60... Standard for particulate matter. (a) On and after the date of which the performance test required to be... control device and contain particulate matter in excess of 12 mg/dscm (0.0052 gr/dscf); (2) Exit from a...
40 CFR 60.272 - Standard for particulate matter.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standard for particulate matter. 60.272... Standard for particulate matter. (a) On and after the date on which the performance test required to be... control device and contain particulate matter in excess of 12 mg/dscm (0.0052 gr/dscf). (2) Exit from a...
NASA Technical Reports Server (NTRS)
Cukor, P. M.; Chapman, R. A.
1978-01-01
The uncertainties and associated costs involved in selecting and designing a particulate control device to meet California's air emission regulations are considered. The basic operating principles of electrostatic precipitators and fabric filters are discussed, and design parameters are identified. The size and resulting cost of the control device as a function of design parameters is illustrated by a case study for an 800 MW coal-fired fired utility boiler burning a typical southwestern subbituminous coal. The cost of selecting an undersized particulate control device is compared with the cost of selecting an oversized device.
Ji, Ye; Xu, Gong Ping; Zhang, Zhi Peng; Xia, Jing Jun; Yan, Jing Long; Pan, Shang Ha
2010-03-01
Autogenous bone grafts are widely used in the repair of bone defects. Growth factors such as bone morphogenetic protein 2 (BMP-2) can induce bone regeneration and enhance bone growth. The combination of an autogenous bone graft and BMP-2 may provide a better osteogenic effect than either treatment alone, but BMP-2 is easily inactivated in body fluid. The objective of this study was to develop a technique that can better preserve the in vivo activity of BMP-2 incorporated in bone grafts. In this study, we first prepared BMP-2/poly(lactic-co-glycolic acid) (PLGA) delayed-release microspheres, and then combined collagen, the delayed-release microspheres, and rat autologous bone particulates to form four groups of composite grafts with different combinations: collagen in group A; collagen combined with bone particulates in group B; collagen combined with BMP-2/PLGA delayed-release microspheres in group C; and collagen combined with both bone particulates and BMP-2/PLGA delayed-release microspheres in group D. The four groups of composite grafts were implanted into the gluteus maximus pockets in rats. The ectopic osteogenesis and ALP level in group D (experimental group) were compared with those in groups A, B, and C (control groups) to study whether it had higher osteogenic capability. Results showed that the composite graft design increased the utility of BMP-2 and reduced the required dose of BMP-2 and volume of autologous bone. The selection of bone particulate diameter had an impact on the osteogenetic potential of bone grafts. Collagen prevented the occurrence of aseptic inflammation and improved the osteoinductivity of BMP-2. These results showed that this composite graft design is effective and feasible for use in bone repair.
40 CFR 52.330 - Control strategy: Total suspended particulates.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Control strategy: Total suspended particulates. 52.330 Section 52.330 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Colorado § 52.330 Control strategy...
THE IMPACT OF PARTICULATE EMISSIONS CONTROL ON THE CONTROL OF OTHER MWC AIR EMISSIONS
On December 20, 1989, the Environmental Protection Agency (EPA) proposed revised new source performance standards for new municipal waste combustion (MWC) units and guidelines for existing sources. The proposed national regulations require tighter particulate matter control and a...
Lin, Chi-Chi; Huang, Hsiao-Lin; Hsiao, Wen-Yuan
2016-01-01
Past studies indicated particulates generated by waste incineration contain various hazardous compounds. The aerosol characteristics are very important for particulate hazard control and workers' protection. This study explores the detailed characteristics of emitted particulates from each important operation unit in a rotary kiln-based hazardous industrial waste incineration plant. A dust size analyzer (Grimm 1.109) and a scanning mobility particle sizer (SMPS) were used to measure the aerosol mass concentration, mass size distribution, and number size distribution at five operation units (S1-S5) during periods of normal operation, furnace shutdown, and annual maintenance. The place with the highest measured PM10 concentration was located at the area of fly ash discharge from air pollution control equipment (S5) during the period of normal operation. Fine particles (PM2.5) constituted the majority of the emitted particles from the incineration plant. The mass size distributions (elucidated) made it clear that the size of aerosols caused by the increased particulate mass, resulting from work activities, were mostly greater than 1.5 μm. Whereas the number size distributions showed that the major diameters of particulates that caused the increase of particulate number concentrations, from work activities, were distributed in the sub micrometer range. The process of discharging fly ash from air pollution control equipment can significantly increase the emission of nanoparticles. The mass concentrations and size distributions of emitted particulates were different at each operation unit. This information is valuable for managers to take appropriate strategy to reduce the particulate emission and associated worker exposure.
NASA Astrophysics Data System (ADS)
Dong, Yuan; Li, Qian P.; Wu, Zhengchao; Zhang, Jia-Zhong
2016-12-01
Export fluxes of phosphorus (P) by sinking particles are important in studying ocean biogeochemical dynamics, whereas their composition and temporal variability are still inadequately understood in the global oceans, including the northern South China Sea (NSCS). A time-series study of particle fluxes was conducted at a mooring station adjacent to the Xisha Trough in the NSCS from September 2012 to September 2014, with sinking particles collected every two weeks by two sediment traps deployed at 500 m and 1500 m depths. Five operationally defined particulate P classes of sinking particles including loosely-bound P, Fe-bound P, CaCO3-bound P, detrital apatite P, and refractory organic P were quantified by a sequential extraction method (SEDEX). Our results revealed substantial variability in sinking particulate P composition at the Xisha over two years of samplings. Particulate inorganic P was largely contributed from Fe-bound P in the upper trap, but detrital P in the lower trap. Particulate organic P, including exchangeable organic P, CaCO3-bound organic P, and refractory organic P, contributed up to 50-55% of total sinking particulate P. Increase of CaCO3-bound P in the upper trap during 2014 could be related to a strong El Niño event with enhanced CaCO3 deposition. We also found sediment resuspension responsible for the unusual high particles fluxes at the lower trap based on analyses of a two-component mixing model. There was on average a total mass flux of 78±50 mg m-2 d-1 at the upper trap during the study period. A significant correlation between integrated primary productivity in the region and particle fluxes at 500 m of the station suggested the important role of biological production in controlling the concentration, composition, and export fluxes of sinking particulate P in the NSCS.
Diagnostics of Thermal Spraying Plasma Jets
NASA Astrophysics Data System (ADS)
Fauchais, P.; Coudert, J. F.; Vardelle, M.; Vardelle, A.; Denoirjean, A.
D.C. thermal plasma jets are strongly affected on the one hand by the arc root fluctuations at the anode, resulting in a type of pulsed flow and enhanced turbulence, and on the other hand by the entrainment of surrounding cold gas in the plasma jet. These phenomena and the resulting temperature distributions have been studied using a wide range of diagnostic techniques including fast cameras, laser doppler anemometry (LDA), coherent anti-Stokes Raman spectroscopy (CARS), Rayleigh scattering, emission spectroscopy, Schlieren photography, enthalpy probes and sampling probes. The information given by these techniques is evaluated and compared. The effect of the arc fluctuations on the spectroscopic measurements is emphasized and the possibility of using these fluctuations to determine informations on the arc behaviour and the axial velocity of the jet is presented. Optimization of plasma processing of solid particules requires information about their size and surface temperature, as well as number flux and velocity distributions at various locations in the flow field. The different statistical techniques of in-flight measurements are discussed together with their limitations. A method to determine the temperature and species density of the vapor cloud or comet travelling with each particule in flight is then presented. However, such statistical measurements present ambiguities in their interpretation, which can be adressed only by additional measurements to determine the velocity, diameter, and surface temperature of a single particule in flight. Moreover, information on single particules is required in order to understand the coating properties, which depend strongly on the way the particules flatten and solidify upon impact. A method to obtain data related to a single particule in flight and to follow the temperature evolution of the corresponding splat upon cooling is presented. The paper concludes with the description of the experimental techniques to follow the temperature evolution of the successive layers and passes. This is important because temperature distribution within coating and substrate controls the adhesion and cohesion of coatings as well as their residual stress.
Code of Federal Regulations, 2014 CFR
2014-07-01
... IMPLEMENTATION PLANS California § 52.227 Control strategy and regulations: Particulate matter, Metropolitan Los... Los Angeles Intrastate Region. (1) Los Angeles County Air Pollution Control District: (i) Regulation IV, Rule 68.1. (2) Riverside County Air Pollution Control District: (i) Regulation IV, Rule 54 for...
Code of Federal Regulations, 2013 CFR
2013-07-01
... IMPLEMENTATION PLANS California § 52.227 Control strategy and regulations: Particulate matter, Metropolitan Los... Los Angeles Intrastate Region. (1) Los Angeles County Air Pollution Control District: (i) Regulation IV, Rule 68.1. (2) Riverside County Air Pollution Control District: (i) Regulation IV, Rule 54 for...
Code of Federal Regulations, 2012 CFR
2012-07-01
... IMPLEMENTATION PLANS California § 52.227 Control strategy and regulations: Particulate matter, Metropolitan Los... Los Angeles Intrastate Region. (1) Los Angeles County Air Pollution Control District: (i) Regulation IV, Rule 68.1. (2) Riverside County Air Pollution Control District: (i) Regulation IV, Rule 54 for...
Advanced Hybrid Particulate Collector Project Management Plan
DOE Office of Scientific and Technical Information (OSTI.GOV)
Miller, S.J.
As the consumption of energy increases, its impact on ambient air quality has become a significant concern. Recent studies indicate that fine particles from coal combustion cause health problems as well as atmospheric visibility impairment. These problems are further compounded by the concentration of hazardous trace elements such as mercury, cadmium, selenium, and arsenic in fine particles. Therefore, a current need exists to develop superior, but economical, methods to control emissions of fine particles. Since most of the toxic metals present in coal will be in particulate form, a high level of fine- particle collection appears to be the bestmore » method of overall air toxics control. However, over 50% of mercury and a portion of selenium emissions are in vapor form and cannot be collected in particulate control devices. Therefore, this project will focus on developing technology not only to provide ultrahigh collection efficiency of particulate air toxic emissions, but also to capture vapor- phase trace metals such as mercury and selenium. Currently, the primary state-of-the-art technologies for particulate control are fabric filters (baghouses) and electrostatic precipitators (ESPs). However, they both have limitations that prevent them from achieving ultrahigh collection of fine particulate matter and vapor-phase trace metals. The objective of this project is to develop a highly reliable advanced hybrid particulate collector (AHPC) that can provide > 99.99 % particulate collection efficiency for all particle sizes between 0.01 and 50 14m, is applicable for use with all U.S. coals, and is cost-0443competitive with existing technologies. Phase I of the project is organized into three tasks: Task I - Project Management, Reporting, and Subcontract Consulting Task 2 - Modeling, Design, and Construction of 200-acfm AHPC Model Task 3 - Experimental Testing and Subcontract Consulting« less
Wooten, Kimberly J; Sandoz, Melissa A; Smith, Philip N
2018-04-01
Beef cattle in the United States are routinely administered ractopamine, a β-adrenergic receptor agonist, to enhance growth. The present study is the first to quantify ractopamine in feedyard-emitted particulate matter and playa wetlands near feedyards. Ractopamine was present in 92% of particulate matter samples, 16% of playa sediment samples, and 3% of playa water samples, at maximum concentrations of 4.7 μg/g, 5.2 ng/g (dry wt), and 271 ng/L, respectively. These data suggest that aerial transmission and deposition of particulate matter is a transport mechanism for ractopamine between feedyards and aquatic systems in the region. Environ Toxicol Chem 2018;37:970-974. © 2017 SETAC. © 2017 SETAC.
Dang, Feng; Wan, Chunlei; Park, Nam-Hee; Tsuruta, Kazuki; Seo, Won-Seon; Koumoto, Kunihito
2013-11-13
Self-assembled particulate films with a uniform structure over a large area were prepared from La-SrTiO3 nanocubes for thermoelectric applications. UV irradiation was used to assist the formation of particulate film for decomposition of the organic phase in situ to obtain a mechanically robust structure at high temperature. The thermoelectric properties of the particulate film were measured after calcination at 1000 °C under a reductive atmosphere (Ar/H2 = 60/40). A Seebeck coefficient of S = -239 ± 24 μV/K, electrical conductivity of σ = 160 ± 5 S/cm, and thermal conductivity of κ ≈ 1.5 W/mK were obtained for a self-assembled particulate film (La: 5%) corresponding to a ZT value of 0.2 at room temperature, which exceeded that of a La-SrTiO3 single crystal with similar composition.
40 CFR 52.1783 - Original identification of plan section.
Code of Federal Regulations, 2013 CFR
2013-07-01
... of Particulates from Hot Mix Asphalt Plants 2D.0507—Particulates from Chemical Fertilizer Manufacturing Plants 2D.0508—Control of Particulates from Pulp and Paper Mills 2D.0509—Particulates from Mica or... Emissions from Bulk Gasoline Terminals 2D.0918—Can Coating 2D.0919—Coil Coating 2D.0920—Paper Coating 2D...
40 CFR 52.1783 - Original identification of plan section.
Code of Federal Regulations, 2012 CFR
2012-07-01
... of Particulates from Hot Mix Asphalt Plants 2D.0507—Particulates from Chemical Fertilizer Manufacturing Plants 2D.0508—Control of Particulates from Pulp and Paper Mills 2D.0509—Particulates from Mica or... Emissions from Bulk Gasoline Terminals 2D.0918—Can Coating 2D.0919—Coil Coating 2D.0920—Paper Coating 2D...
40 CFR 52.1783 - Original identification of plan section.
Code of Federal Regulations, 2011 CFR
2011-07-01
... of Particulates from Hot Mix Asphalt Plants 2D.0507—Particulates from Chemical Fertilizer Manufacturing Plants 2D.0508—Control of Particulates from Pulp and Paper Mills 2D.0509—Particulates from Mica or... Emissions from Bulk Gasoline Terminals 2D.0918—Can Coating 2D.0919—Coil Coating 2D.0920—Paper Coating 2D...
Cost Effectiveness Of Selected Roadway Dust Control Methods For Eagle River, Alaska
DOT National Transportation Integrated Search
1988-01-01
The U.S. Environmental Protection Agency has set air quality standards for airborne particulates with diameters equal to or less than ten microns (PM10 particulates). These particulates have been correlated with respiratory illnesses. The primary sta...
INTERNATIONAL APPROACHES TO DEVELOPING STANDARDS FOR NONCRITERIA POLLUTANTS
Much of the initial interest in the control of pollutants, both in the United States and abroad, focused on such "traditional" pollutants as sulfur dioxide, particulate matter, Total Suspended Particulate (TSP) and particulate matter, nitrogen oxides, carbon monoxide, ozone, and ...
Monitoring by Control Technique - Wet Scrubber For Particulate Matter
Stationary source emissions monitoring is required to demonstrate that a source is meeting the requirements in Federal or state rules. This page is about Wet Scrubber For Particulate Matter controls used to reduce pollutant emissions.
Duct having oscillatory side wall
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sprouse, Kenneth M.
A pump system includes a particulate consolidator pump that has a pump outlet. A duct is coupled to the pump outlet. The duct has a wall that is coupled with an oscillator. The oscillator is operable to oscillate the wall at a controlled frequency. The controlled frequency is selected with respect to breaking static bridging of particulate in the duct due, at least in part, to consolidation of the particulate from a downstream check valve.
NASA Astrophysics Data System (ADS)
Turnewitsch, Robert; Dale, Andrew; Lahajnar, Niko; Lampitt, Richard S.; Sakamoto, Kei
2017-05-01
Before particulate matter that settles as 'primary flux' from the interior ocean is deposited into deep-sea sediments it has to traverse the benthic boundary layer (BBL) that is likely to cover almost all parts of the seafloor in the deep seas. Fluid dynamics in the BBL differ vastly from fluid dynamics in the overlying water column and, consequently, have the potential to lead to quantitative and compositional changes between primary and depositional fluxes. Despite this potential and the likely global relevance very little is known about mechanistic and quantitative aspects of the controlling processes. Here, results are presented for a sediment-trap time-series study that was conducted on the Porcupine Abyssal Plain in the abyssal Northeast Atlantic, with traps deployed at 2, 40 and 569 m above bottom (mab). The two bottommost traps were situated within the BBL-affected part of the water column. The time series captured 3 neap and 4 spring tides and the arrival of fresh settling material originating from a surface-ocean bloom. In the trap-collected material, total particulate matter (TPM), particulate inorganic carbon (PIC), biogenic silica (BSi), particulate organic carbon (POC), particulate nitrogen (PN), total hydrolysable amino acids (AA), hexosamines (HA) and lithogenic material (LM) were determined. The biogeochemical results are presented within the context of time series of measured currents (at 15 mab) and turbidity (at 1 mab). The main outcome is evidence for an effect of neap/spring tidal oscillations on particulate-matter dynamics in BBL-affected waters in the deep sea. Based on the frequency-decomposed current measurements and numerical modelling of BBL fluid dynamics, it is concluded that the neap/spring tidal oscillations of particulate-matter dynamics are less likely due to temporally varying total free-stream current speeds and more likely due to temporally and vertically varying turbulence intensities that result from the temporally varying interplay of different rotational flow components (residual, tidal, near-inertial) within the BBL. Using information from previously published empirical and theoretical relations between fluid and biogeochemical dynamics at the scale of individual particle aggregates, a conceptual and semi-quantitative picture of a mechanism was derived that explains how the neap/spring fluid-dynamic oscillations may translate through particle dynamics into neap/spring oscillations of biogeochemical aggregate decomposition (microbially driven organic-matter breakdown, biomineral dissolution). It is predicted that, during transitions from neap into spring tides, increased aggregation in near-seafloor waters and/or reduced deposition of aggregates at the seafloor coincides with reduced biogeochemical particulate-matter decomposition in near-seafloor waters. By contrast, during transitions from spring into neap tides, enhanced biogeochemical particulate-matter decomposition in near-seafloor waters is predicted to coincide with increased deposition of particulate matter at the seafloor. This study suggests that, in addition to current speed, the specifics and subtleties of the interplay of different rotational flow components can be an important control on how the primary flux from the interior ocean is translated into the depositional flux, with potential implications for sedimentary carbon deposition, benthic food supply and possibly even the sedimentary records of environmental change.
Research on particulate filter simulation and regeneration control strategy
NASA Astrophysics Data System (ADS)
Dawei, Qu; Jun, Li; Yu, Liu
2017-03-01
This paper reports a DPF (Diesel Particulate Filter) collection mathematical model for a new regeneration control strategy. The new strategy is composed by main parts, such as regeneration time capturing, temperature rising strategy and regeneration control strategy. In the part of regeneration time capturing, a multi-level regeneration capturing method is put forward based on the combined effect of the PM (Particulate Matter) loading, pressure drop and fuel consumption. The temperature rising strategy proposes the global temperature for all operating conditions. The regeneration control process considers the particle loading density, temperature and oxygen respectively. Based on the analysis of the initial overheating, runaway temperature and local hot spot, the final control strategy is established.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-09-27
... particulates and other potential pollutants present on pavement, specific effluent limits have been included to ensure particulates and other potential pollutants mobilized by pavement washing are controlled via treatment controls before they are discharged, unless the pavement wash waters were treated by the control...
Baghouses are air pollution control devices used to control particulate emissions from stationary sources and are among the technologies evaluated by the APCT Center. Baghouses and their accompanying filter media have long been one of the leading particulate control techniques fo...
Baghouses are air pollution control devices used to control particulate emissions from stationary sources and are among the technologies evaluated by the APCT Center. Baghouses and their accompanying filter media have long been one of the leading particulate control techniques fo...
Baghouses are air pollution control devices used to control particulate emissions from stationary sources and are among the technologies evaluated by the APCT Center. Baghouses and their accompanying filter media have long been one of the leading particulate control techniques fo...
DOE Office of Scientific and Technical Information (OSTI.GOV)
England, G.C.; Kwan, Y.; Payne, R.
1984-10-01
The paper discusses a program that addresses the need for advanced NOx control technology for thermally enhanced oil recovery (TEOR) steam generators. A full-scale (60 million Btu/hr) burner system has been developed and tested, the concept for which was based on fundamental studies. Test results are included for full-scale burner performance in an experimental test furnace, and in a field-operating steam generator which was subsequently retrofitted in a Kern County, California, oilfield. (NOTE: NOx control techniques including low-NOx burners, postflame NH/sub 3/ injection, or other postflame treatment methods--e.g., selective catalytic reduction--have been considered in order to comply with regulations. Themore » level of NOx control required to meet both growth and air quality goals has typically been difficult to achieve with available technology while maintaining acceptable CO and particulate emissions as well as practical flame conditions within the steamer.)« less
Technology Base Enhancement Program. Metal Matrix Composites
1993-08-30
efficiency, improved structural reliability, and reduced maintenance when compared to carbon fiber reinforced composites . Aerospace engines (in particular...different materials. The composite consists of a metal matrix reinforced with particulates, flakes, whiskers,3 continuous fibers , filaments, wires, or...graphite and carbon to metals. They come in three general forms: particulates (or particles) with a length to diameter ratio of about 1; chopped fibers or
40 CFR 52.725 - Control strategy: Particulates.
Code of Federal Regulations, 2011 CFR
2011-07-01
... requests to redesignate the Granite City Particulate Matter (PM) nonattainment area to attainment status... Granite City area to ensure continued attainment of the NAAQS. The redesignation request and maintenance... the Lake Calumet (SE Chicago), McCook, and Granite City, Illinois, Particulate Matter (PM...
40 CFR 52.725 - Control strategy: Particulates.
Code of Federal Regulations, 2010 CFR
2010-07-01
... requests to redesignate the Granite City Particulate Matter (PM) nonattainment area to attainment status... Granite City area to ensure continued attainment of the NAAQS. The redesignation request and maintenance... the Lake Calumet (SE Chicago), McCook, and Granite City, Illinois, Particulate Matter (PM...
40 CFR 52.725 - Control strategy: Particulates.
Code of Federal Regulations, 2013 CFR
2013-07-01
... requests to redesignate the Granite City Particulate Matter (PM) nonattainment area to attainment status... Granite City area to ensure continued attainment of the NAAQS. The redesignation request and maintenance... the Lake Calumet (SE Chicago), McCook, and Granite City, Illinois, Particulate Matter (PM...
40 CFR 52.725 - Control strategy: Particulates.
Code of Federal Regulations, 2014 CFR
2014-07-01
... requests to redesignate the Granite City Particulate Matter (PM) nonattainment area to attainment status... Granite City area to ensure continued attainment of the NAAQS. The redesignation request and maintenance... the Lake Calumet (SE Chicago), McCook, and Granite City, Illinois, Particulate Matter (PM...
Numerous epidemiological studies have found associations between airborne particulate matter measured at community monitors and increased mortality and morbidity. Chemical and physical characteristics of particulate matter (e.g., elemental composition, size) and source identifi...
PARTICULATE CONTROL HIGHLIGHTS: RESEARCH ON ELECTROSTATIC PRECIPITATOR TECHNOLOGY
The report gives highlights of a major EPA research program on electrostatic precipitator (ESP) technology, directed toward improving the performance of ESPs in controlling industrial particulate emissions, notably fly ash from coal combustion in electric power plants. Relationsh...
Chiang, Ta-Kuan; Straub, Douglas L.; Dennis, Richard A.
2000-01-01
The present invention involves a porous rigid filter including a plurality of concentric filtration elements having internal flow passages and forming external flow passages there between. The present invention also involves a pressure vessel containing the filter for the removal of particulates from high pressure particulate containing gases, and further involves a method for using the filter to remove such particulates. The present filter has the advantage of requiring fewer filter elements due to the high surface area-to-volume ratio provided by the filter, requires a reduced pressure vessel size, and exhibits enhanced mechanical design properties, improved cleaning properties, configuration options, modularity and ease of fabrication.
NASA Astrophysics Data System (ADS)
Singh, R. K.; Kim, W.-S.; Ollinger, M.; Craciun, V.; Coowantwong, I.; Hochhaus, G.; Koshizaki, N.
2002-09-01
There is an urgent need to develop controlled drug release systems for the delivery of drugs via the pulmonary route. A key issue in pulmonary dry delivery systems is to reduce the amount of biodegradable polymers that are added to control the drug release. We have synthesized nanofunctionalized drug particles using the pulsed laser deposition on particles (PLDP) (e.g. budesonide) in an effort to control the architecture and thickness of a nanoscale polymer coating on the drug particles. In vitro studies indicated that the dry half-life release for budesonide can be enhanced from 1.2 to over 60 min by a nanoscale coating on the drug particle. Extensive studies have been conducted to characterize the bonding and composition of the polymer film deposited on drug particles.
Maximum sinking velocities of suspended particulate matter in a coastal transition zone
NASA Astrophysics Data System (ADS)
Maerz, Joeran; Hofmeister, Richard; van der Lee, Eefke M.; Gräwe, Ulf; Riethmüller, Rolf; Wirtz, Kai W.
2016-09-01
Marine coastal ecosystem functioning is crucially linked to the transport and fate of suspended particulate matter (SPM). Transport of SPM is controlled by, amongst other factors, sinking velocity ws. Since the ws of cohesive SPM aggregates varies significantly with size and composition of the mineral and organic origin, ws exhibits large spatial variability along gradients of turbulence, SPM concentration (SPMC) and SPM composition. In this study, we retrieved ws for the German Bight, North Sea, by combining measured vertical turbidity profiles with simulation results for turbulent eddy diffusivity. We analyzed ws with respect to modeled prevailing dissipation rates ɛ and found that mean ws were significantly enhanced around log10(ɛ (m2 s-3)) ≈ -5.5. This ɛ region is typically found at water depths of approximately 15 to 20 m along cross-shore transects. Across this zone, SPMC declines towards the offshore waters and a change in particle composition occurs. This characterizes a transition zone with potentially enhanced vertical fluxes. Our findings contribute to the conceptual understanding of nutrient cycling in the coastal region which is as follows. Previous studies identified an estuarine circulation. Its residual landward-oriented bottom currents are loaded with SPM, particularly within the transition zone. This retains and traps fine sediments and particulate-bound nutrients in coastal waters where organic components of SPM become remineralized. Residual surface currents transport dissolved nutrients offshore, where they are again consumed by phytoplankton. Algae excrete extracellular polymeric substances which are known to mediate mineral aggregation and thus sedimentation. This probably takes place particularly in the transition zone and completes the coastal nutrient cycle. The efficiency of the transition zone for retention is thus suggested as an important mechanism that underlies the often observed nutrient gradients towards the coast.
Deep-sea fluxes of barium and lithogenic trace elements in the subtropical northeast Atlantic
NASA Astrophysics Data System (ADS)
Stern, Judith; Dellwig, Olaf; Waniek, Joanna J.
2017-04-01
Total particle flux, Barium and lithogenic trace element fluxes were measured at the mooring Kiel 276 (33°N, 22°W) in the deep-sea of the subtropical Northeast Atlantic. The particulate material was collected between 2002 and 2008 with a sediment trap in 2000 m depth and analyzed with ICP-OES/-MS to determine its geochemical composition. The particle flux is controlled by primary production, lithogenic particle inputs via atmospheric transport and the migration of the Azores Front. We used refractory trace elements (eg. Ti, Zr, and the rare earth elements) to demonstrate the changes in flux and composition of the material due to lithogenic inputs. Shortly after periods of high dust load and enhanced primary production an increase in lithogenic trace element fluxes occurred. Especially the formation of aggregates with biogenic matter seems to have a major impact on the downwards transport of lithogenic particles. The observation of particulate Ba is of great interest since it is known as a proxy for past and present primary production. Ba fluxes ranging between 0.02 mg m-2 d-1 and 1.21 mg m-2 d-1 with biogenic proportions up to 97%. The fluxes of particulate Barium in the water column are mainly attributed to the strength of primary production.
NASA Astrophysics Data System (ADS)
Philip, Sajeev; Martin, Randall V.; Snider, Graydon; Weagle, Crystal L.; van Donkelaar, Aaron; Brauer, Michael; Henze, Daven K.; Klimont, Zbigniew; Venkataraman, Chandra; Guttikunda, Sarath K.; Zhang, Qiang
2017-04-01
Global measurements of the elemental composition of fine particulate matter across several urban locations by the Surface Particulate Matter Network reveal an enhanced fraction of anthropogenic dust compared to natural dust sources, especially over Asia. We develop a global simulation of anthropogenic fugitive, combustion, and industrial dust which, to our knowledge, is partially missing or strongly underrepresented in global models. We estimate 2-16 μg m-3 increase in fine particulate mass concentration across East and South Asia by including anthropogenic fugitive, combustion, and industrial dust emissions. A simulation including anthropogenic fugitive, combustion, and industrial dust emissions increases the correlation from 0.06 to 0.66 of simulated fine dust in comparison with Surface Particulate Matter Network measurements at 13 globally dispersed locations, and reduces the low bias by 10% in total fine particulate mass in comparison with global in situ observations. Global population-weighted PM2.5 increases by 2.9 μg m-3 (10%). Our assessment ascertains the urgent need of including this underrepresented fine anthropogenic dust source into global bottom-up emission inventories and global models.
Source contributions of fine particulate matter during one winter haze episodes in Xi'an, China
NASA Astrophysics Data System (ADS)
Yang, X.; Wu, Q.
2017-12-01
Long-term exposure to high levels of fine particulate matter (PM2.5) is found to be associated with adverse effects on human health, ecological environment and climate change. Identification the major source regions of fine particulate matter are essential to proposing proper joint prevention and control strategies for heavy haze mitigation. In this work, the Comprehensive Air Quality Model with extensions (CAMx) together with the Particulate Source Apportionment Technology (PSAT) and the Weather Research and Forecast Model (WRF), have been applied to analyze the major source regions of PM2.5 in Xi'an during the heavy haze episodes in winter (29, December, 2016 - 5 January 2017), and the framework of the model system is shown in Fig. 1. Firstly, according to the model evaluation of the daily PM2.5 concentrations for the two months, the model has well performance, and the fraction of predictions within a factor of 2 of the observations (FAC2) is 84%, while the correlation coefficient (R) is 0.80 in Xi'an. By using the PSAT in CAMx model, a detailed source region contribution matrix is derived for all points within the Xi'an region and its six surrounding areas, and long-range regional transport. The results show that the local emission in Xi'an is the mainly sources at downtown area, which contributing 72.9% as shown in Fig.2, and the contribution rate of transportations between adjacent areas depends on wind direction. Meanwhile, three different suburban areas selected for detailed analysis in fine particles sources. Comparing to downtown area, the sources of suburban areas are more multiply, and the transportations make the contribution 40%-82%. In the suburban areas, regional inflows play an important role in the fine particles concentrations, indicating a strong need for regional joint emission control efforts. The results enhance the quantitative understanding of the PM2.5 source regions and provide a basis for policymaking to advance the control of pollution in Xi'an, China.
Transported vs. local contributions from secondary and biomass burning sources to PM2.5
NASA Astrophysics Data System (ADS)
Kim, Bong Mann; Seo, Jihoon; Kim, Jin Young; Lee, Ji Yi; Kim, Yumi
2016-11-01
The concentration of fine particulates in Seoul, Korea has been lowered over the past 10 years, as a result of the city's efforts in implementing environmental control measures. Yet, the particulate concentration level in Seoul remains high as compared to other urban areas globally. In order to further improve fine particulate air quality in the Korea region and design a more effective control strategy, enhanced understanding of the sources and contribution of fine particulates along with their chemical compositions is necessary. In turn, relative contributions from local and transported sources on Seoul need to be established, as this city is particularly influenced by sources from upwind geographic areas. In this study, PM2.5 monitoring was conducted in Seoul from October 2012 to September 2013. PM2.5 mass concentrations, ions, metals, organic carbon (OC), elemental carbon (EC), water soluble OC (WSOC), humic-like substances of carbon (HULIS-C), and 85 organic compounds were chemically analyzed. The multivariate receptor model SMP was applied to the PM2.5 data, which then identified nine sources and estimated their source compositions as well as source contributions. Prior studies have identified and quantified the transported and local sources. However, no prior studies have distinguished contributions of an individual source between transported contribution and locally produced contribution. We differentiated transported secondary and biomass burning sources from the locally produced secondary and biomass burning sources, which was supported with potential source contribution function (PSCF) analysis. Of the total secondary source contribution, 32% was attributed to transported secondary sources, and 68% was attributed to locally formed secondary sources. Meanwhile, the contribution from the transported biomass burning source was revealed as 59% of the total biomass burning contribution, which was 1.5 times higher than that of the local biomass burning source. Four-season average source contributions from the transported and the local sources were 28% and 72%, respectively.
Inductively heated particulate matter filter regeneration control system
Gonze, Eugene V; Paratore Jr., Michael J; Kirby, Kevin W; Phelps, Amanda; Gregoire, Daniel J
2012-10-23
A system includes a particulate matter (PM) filter with an upstream end for receiving exhaust gas, a downstream end and zones. The system also includes a heating element. A control module selectively activates the heating element to inductively heat one of the zones.
Chang, Chang-Tang; Chang, Yu-Min; Lin, Wen-Yinn; Wu, Ming-Ching
2010-10-01
Particles emitted from gravel processing sites are one contributor to worsening air quality in Taiwan. Major pollution sources at gravel processing sites include gravel and sand piles, unpaved roads, material crushers, and bare ground. This study analyzed fugitive dust emission characteristics at each pollution source using several types of particle samplers, including total suspended particulates (TSP), suspended particulate (PM10), fine suspended particulate (PM2.5), particulate sizer, and dust-fall collectors. Furthermore, silt content and moisture in the gravel were measured to develop particulate emission factors. The results showed that TSP (< 100 microm) concentrations at the boundary of gravel sites ranged from 280 to 1290 microg/m3, which clearly exceeds the Taiwan hourly air quality standard of 500 microg/m3. Moreover, PM10 concentrations, ranging from 135 to 550 microg/m3, were also above the daily air quality standard of 125 microg/m3 and approximately 1.2 and 1.5 times the PM2.5 concentrations, ranging from 105 to 470 microg/m3. The size distribution analysis reveals that mass mean diameter and geometric standard deviation ranged from 3.2 to 5.7 microm and from 2.82 to 5.51, respectively. In this study, spraying surfactant was the most effective control strategy to abate windblown dust from unpaved roads, having a control efficiency of approximately 93%, which is significantly higher than using paved road strategies with a control efficiency of approximately 45%. For paved roads, wet suppression provided the best dust control efficiencies ranging from 50 to 83%. Re-vegetation of disturbed ground had dust control efficiencies ranging from 48 to 64%.
Population exposure to ambient particulate matter (PM) has received considerable attention due to the association between ambient particulate concentrations and mortality. Current toxicological studies and controlled human and animal exposures suggest that all size fractions of...
NASA Technical Reports Server (NTRS)
Hotaling, S. P.
1993-01-01
Two samples from Long Duration Exposure Facility (LDEF) experiment M0003-4 were analyzed for molecular and particulate contamination prior to and following treatment with advanced satellite contamination removal techniques (CO2 gas/solid jet spray and oxygen ion beam). The pre- and post-cleaning measurements and analyses are presented. The jet spray removed particulates in seconds. The low energy reactive oxygen ion beam removed 5,000 A of photo polymerized organic hydrocarbon contamination in less than 1 hour. Spectroscopic analytical techniques were applied to the analysis of cleaning efficiency including: Fourier transform infrared, Auger, x ray photoemissions, energy dispersive x ray, and ultraviolet/visible. The results of this work suggest that the contamination studied here was due to spacecraft self-contamination enhanced by atomic oxygen plasma dynamics and solar UV radiation. These results also suggest the efficacy for the jet spray and ion beam contamination control technologies for spacecraft optical surfaces.
Yang, Taeseung; Choi, Sang Koo; Park, Daehwan; Lee, Yea Ram; Chung, Chan Bok; Kim, Jin Woong
2016-12-20
This study introduces a new type of associative nanoparticle (ANP) that provides controlled chain-to-chain attraction with an associative polymer rheology modifier (APRM) to produce highly stable Pickering emulsions. The ANPs were synthesized by grafting hydrophobically modified hygroscopic zwitterionic poly(2-methacryloyloxyethyl phosphorylcholine-co-stearyl methacrylate) brushes onto 20 nm sized silica NPs via surface-mediated living radical polymerization. The ANP-stabilized Pickering emulsions show significant viscosity enhancement in the presence of the APRM. This indicates that the ANPs act as particulate concentration agents at the interface owing to their hydrophobic association with the APRM in the aqueous phase, which leads to the generation of an ANP-mediated complex colloidal film. Consequently, the described ANP-reinforced Pickering emulsion system exhibits improved resistance to pH and salinity changes. This coacervation approach is advantageous because the complex colloidal layer at the interface provides the emulsion drops with a mechanically robust barrier, thus guaranteeing the improved Pickering emulsion stability against harsh environmental factors.
Settling Efficiency of Urban Particulate Matter Transported by Stormwater Runoff.
Carbone, Marco; Penna, Nadia; Piro, Patrizia
2015-09-01
The main purpose of control measures in urban areas is to retain particulate matter washed out by stormwater over impermeable surfaces. In stormwater control measures, particulate matter removal typically occurs via sedimentation. Settling column tests were performed to examine the settling efficiency of such units using monodisperse and heterodisperse particulate matter (for which the particle size distributions were measured and modelled by the cumulative gamma distribution). To investigate the dependence of settling efficiency from the particulate matter, a variant of the evolutionary polynomial regression (EPR), a Microsoft Excel function based on multi-objective EPR technique (EPR-MOGA), called EPR MOGA XL, was used as a data-mining strategy. The results from this study have shown that settling efficiency is a function of the initial total suspended solids (TSS) concentration and of the median diameter (d50 index), obtained from the particle size distributions (PSDs) of the samples.
Combustor with multistage internal vortices
Shang, Jer Yu; Harrington, R.E.
1987-05-01
A fluidized bed combustor is provided with a multistage arrangement of vortex generators in the freeboard area. The vortex generators are provided by nozzle means which extend into the interior of the freeboard for forming vortices within the freeboard areas to enhance the combustion of particulate material entrained in product gases ascending into the freeboard from the fluidized bed. Each of the nozzles are radially inwardly spaced from the combustor walls defining the freeboard to provide for the formation of an essentially vortex-free, vertically extending annulus about the vortices whereby the particulate material centrifuged from the vortices against the inner walls of the combustor is returned through the annulus to the fluidized bed. By adjusting the vortex pattern within the freeboard, a significant portion of the full cross-sectional area of the freeboard except for the peripheral annulus can be contacted with the turbulent vortical flow for removing the particulate material from the gaseous products and also for enhancing the combustion thereof within the freeboard. 2 figs.
Combustor with multistage internal vortices
Shang, Jer Y.; Harrington, Richard E.
1989-01-01
A fluidized bed combustor is provided with a multistage arrangement of vortex generators in the freeboard area. The vortex generators are provided by nozzle means which extend into the interior of the freeboard for forming vortices within the freeboard area to enhance the combustion of particulate material entrained in product gases ascending into the freeboard from the fluidized bed. Each of the nozzles are radially inwardly spaced from the combustor walls defining the freeboard to provide for the formation of an essentially vortex-free, vertically extending annulus about the vortices whereby the particulate material centrifuged from the vortices against the inner walls of the combustor is returned through the annulus to the fluidized bed. By adjusting the vortex pattern within the freeboard, a significant portion of the full cross-sectional area of the freeboard except for the peripheral annulus can be contacted with the turbulent vortical flow for removing the particulate material from the gaseous products and also for enhancing the combustion thereof within the freeboard.
Baghouses are air pollution control devices used to control particulate emissions from stationary sources and are among the technologies evaluated by the APCT Center. Baghouses and their accompanying filter media have long been one of the leading particulate control techniques fo...
40 CFR 52.1678 - Control strategy and regulations: Particulate matter.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy and regulations: Particulate matter. 52.1678 Section 52.1678 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) New York...
The cytotoxicity and genotoxicity of soluble and particulate cobalt in human lung fibroblast cells
DOE Office of Scientific and Technical Information (OSTI.GOV)
Smith, Leah J.; Holmes, Amie L.; Maine Center for Environmental Toxicology and Health, University of Southern Maine, 96 Falmouth St., P.O. Box 9300, Portland, ME 04101-9300
Cobalt exposure is increasing as cobalt demand rises worldwide due to its use in enhancing rechargeable battery efficiency, super-alloys, and magnetic products. Cobalt is considered a possible human carcinogen with the lung being a primary target. However, few studies have considered cobalt-induced toxicity in human lung cells. Therefore, in this study, we sought to determine the cytotoxicity and genotoxicity of particulate and soluble cobalt in human lung cells. Cobalt oxide and cobalt chloride were used as representative particulate and soluble cobalt compounds, respectively. Exposure to both particulate and soluble cobalt induced a concentration-dependent increase in cytotoxicity, genotoxicity, and intracellular cobaltmore » ion levels. Based on intracellular cobalt ion levels, we found that soluble cobalt was more cytotoxic than particulate cobalt while particulate and soluble cobalt induced similar levels of genotoxicity. However, soluble cobalt induced cell cycle arrest indicated by the lack of metaphases at much lower intracellular cobalt concentrations compared to cobalt oxide. Accordingly, we investigated the role of particle internalization in cobalt oxide-induced toxicity and found that particle-cell contact was necessary to induce cytotoxicity and genotoxicity after cobalt exposure. These data indicate that cobalt compounds are cytotoxic and genotoxic to human lung fibroblasts, and solubility plays a key role in cobalt-induced lung toxicity. - Highlights: • Particulate and soluble cobalt are cytotoxic and genotoxic to human lung cells. • Soluble cobalt induces more cytotoxicity compared to particulate cobalt. • Soluble and particulate cobalt induce similar levels of genotoxicity. • Particle-cell contact is required for particulate cobalt-induced toxicity.« less
EMISSION PARTICLE-INDUCED VENTILATORY ABNORMALITIES IN A RAT MODEL OF PULMONARY HYPERTENSION
Abstract
Preexistent cardiopulmonary disease in humans appears to enhance susceptibility to the adverse effects of ambient particulate matter. Previous studies in this laboratory have demonstrated enhanced inflammation and mortality after intratracheal instillation...
Motorcycle pollution control in Taiwan, Republic of China
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, H.W.; Hsiao, H.C.; Walsh, M.P.
1998-12-31
The Taiwan EPA has developed a comprehensive approach to motor vehicle pollution control. Building on its early adoption of US `83 standards for light duty vehicles (starting July 1, 1990) it recently moved to US `87 requirements, which include the 0.2 gram per mile particulate standard, as of July 1, 1995. Heavy duty diesel particulate standards almost as stringent as US `90, 6.0 grams per brake horsepower hour NO{sub x} and 0.7 particulate, using the US transient test procedure, went into effect on July 1, 1993. It is intended that US`94 standards, 5.0 NO{sub x} and 0.25 particulate, will bemore » adopted soon. Clearly the most distinctive feature of the Taiwan program, however, is its motorcycle control effort, reflecting the fact that motorcycles dominate the vehicle fleet and are a substantial source of emissions. This paper will summarize Taiwan`s extensive efforts to address this problem.« less
Atomizing apparatus for making polymer and metal powders and whiskers
Otaigbe, Joshua U.; McAvoy, Jon M.; Anderson, Iver E.; Ting, Jason; Mi, Jia; Terpstra, Robert
2003-03-18
Method for making polymer particulates, such as spherical powder and whiskers, by melting a polymer material under conditions to avoid thermal degradation of the polymer material, atomizing the melt using gas jet means in a manner to form atomized droplets, and cooling the droplets to form polymer particulates, which are collected for further processing. Atomization parameters can be controlled to produce polymer particulates with controlled particle shape, particle size, and particle size distribution. For example, atomization parameters can be controlled to produce spherical polymer powders, polymer whiskers, and combinations of spherical powders and whiskers. Atomizing apparatus also is provided for atoomizing polymer and metallic materials.
ERIC Educational Resources Information Center
Vikström, Anna
2014-01-01
The concept of matter, especially its particulate nature, is acknowledged as being one of the key concept areas in learning science. Within the framework of learning studies and variation theory, and with results from science education research as a starting point, six lower secondary school science teachers tried to enhance students'…
Particulate Air Pollution Control for Army Coal-Fired Boiler Plants.
1983-03-01
Army flue gas . The condensed material usually is sticky and emissions control . Of the current new technologies. traps the flyash on the bag, where it... control device is made a matter of convenience. The location Flue gas temperature control is an important factor of other components is given the prime...consideration. *in the application of baghouses to flue gas particulate This often results in the particle-laden gas being forced control . Bag
DAILY VARIATION OF PARTICULATE AIR POLLUTION AND POOR CARDIAC AUTONOMIC CONTROL IN THE ELDERLY
Particulate matter air pollution (PM) has been related to cardiovascular disease mortality in a number of recent studies. The pathophysiologic mechanisms for this association are under study. Low heart rate variability, a marker of poor cardiac autonomic control, is associated wi...
40 CFR 52.228 - Regulations: Particulate matter, Southeast Desert Intrastate Region.
Code of Federal Regulations, 2012 CFR
2012-07-01
... AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS California... particulate matter in the Southeast Desert Intrastate Region. (1) Imperial County Air Pollution Control District: (i) Rule 114A. (ii) Rule 116B. (2) Los Angeles County Air Pollution Control District: (i...
40 CFR 52.228 - Regulations: Particulate matter, Southeast Desert Intrastate Region.
Code of Federal Regulations, 2014 CFR
2014-07-01
... AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS California... particulate matter in the Southeast Desert Intrastate Region. (1) Imperial County Air Pollution Control District: (i) Rule 114A. (ii) Rule 116B. (2) Los Angeles County Air Pollution Control District: (i...
40 CFR 52.228 - Regulations: Particulate matter, Southeast Desert Intrastate Region.
Code of Federal Regulations, 2013 CFR
2013-07-01
... AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS California... particulate matter in the Southeast Desert Intrastate Region. (1) Imperial County Air Pollution Control District: (i) Rule 114A. (ii) Rule 116B. (2) Los Angeles County Air Pollution Control District: (i...
Lin, Xiao; Chyi, Chin Wun; Ruan, Ke-feng; Feng, Yi; Heng, Paul Wan Sia
2011-10-01
This work aimed to explore the potential of lactose as novel cushioning agents with suitable physicomechanical properties by micronization and co-spray drying with polymers for protecting coated multi-particulates from rupture when they are compressed into tablets. Several commercially available lactose grades, micronized lactose (ML) produced by jet milling, spray-dried ML (SML), and polymer-co-processed SMLs, were evaluated for their material characteristics and tableting properties. Hydroxypropylcellulose (HPC), hydroxypropylmethylcellulose (HPMC), and polyvinylpyrrolidone (PVP) at three different levels were evaluated as co-processed polymers for spray drying. Sugar multi-particulates layered with chlorpheniramine maleate followed by an ethylcellulose coat were tableted using various lactose types as fillers. Drug release from compacted multi-particulate tablets was used to evaluate the cushioning effect of the fillers. The results showed that the cushioning effect of lactose principally depended on its particle size. Micronization can effectively enhance the protective action of lactose. Although spray drying led to a small reduction in the cushioning effect of ML, it significantly improved the physicomechanical properties of ML. Co-spray drying with suitable polymers improved both the cushioning effect and the physicomechanical properties of SML to a certain degree. Among the three polymers studied, HPC was the most effective in terms of enhancing the cushioning effect of SML. This was achieved by reducing yield pressure, and enhancing compressibility and compactibility. The combination of micronization and co-spray drying with polymers is a promising method with which new applications for lactose can be developed. Copyright © 2011 Elsevier B.V. All rights reserved.
Electrically heated DPF start-up strategy
Gonze, Eugene V [Pinckney, MI; Ament, Frank [Troy, MI
2012-04-10
An exhaust system that processes exhaust generated by an engine has a diesel particulate filter (DPF) that is disposed downstream of the engine and that filters particulates in the exhaust. An electrical heater is disposed upstream of the DPF and selectively heats the exhaust to initiate combustion of the particulates. Heat generated by combustion of particulates in the heater induces combustion of particulates within the DPF. A control module selectively enables current flow to the electrical heater for an initial period of a DPF regeneration cycle, and limits exhaust flow while the electrical heater is heating to a predetermined soot combustion temperature.
The report is a guide or convrting U.S. Navy paint spray booth particulate emission control systems from wet to dry operation. The use of water curtains for air pollution control of paint spray booths is considered a major source of water and solid waste pol-lution from industria...
40 CFR 52.1230 - Control strategy and rules: Particulates.
Code of Federal Regulations, 2014 CFR
2014-07-01
... PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Minnesota § 52.1230 Control strategy and rules: Particulates. (a) Part D(1) Approval. The State of Minnesota has satisfied the... provision of Rule 7005.2910. (b) Approval—On May 31, 1988, the State of Minnesota submitted a committal SIP...
40 CFR 52.1230 - Control strategy and rules: Particulates.
Code of Federal Regulations, 2013 CFR
2013-07-01
... PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Minnesota § 52.1230 Control strategy and rules: Particulates. (a) Part D—(1) Approval. The State of Minnesota has satisfied... alternative test method provision of Rule 7005.2910. (b) Approval—On May 31, 1988, the State of Minnesota...
40 CFR 52.1230 - Control strategy and rules: Particulates.
Code of Federal Regulations, 2011 CFR
2011-07-01
... PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Minnesota § 52.1230 Control strategy and rules: Particulates. (a) Part D—(1) Approval. The State of Minnesota has satisfied... alternative test method provision of Rule 7005.2910. (b) Approval—On May 31, 1988, the State of Minnesota...
40 CFR 52.1230 - Control strategy and rules: Particulates.
Code of Federal Regulations, 2012 CFR
2012-07-01
... PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Minnesota § 52.1230 Control strategy and rules: Particulates. (a) Part D—(1) Approval. The State of Minnesota has satisfied... alternative test method provision of Rule 7005.2910. (b) Approval—On May 31, 1988, the State of Minnesota...
40 CFR 52.1230 - Control strategy and rules: Particulates.
Code of Federal Regulations, 2010 CFR
2010-07-01
... PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Minnesota § 52.1230 Control strategy and rules: Particulates. (a) Part D—(1) Approval. The State of Minnesota has satisfied... alternative test method provision of Rule 7005.2910. (b) Approval—On May 31, 1988, the State of Minnesota...
PROCEEDINGS: SEMINAR ON IN-STACK PARTICLE SIZING FOR PARTICULATE CONTROL DEVICE EVALUATION
The proceedings document discussions during an EPA/IERL-RTP-sponsored seminar on In-stack Particle Sizing for Particulate Control Device Evaluation. The seminar, organized by IERL-RTP's Process Measurements Branch, was held at IERL-RTP in North Carolina on December 3 and 4, 1975....
EPA AND ERDA HIGH-TEMPERATURE/HIGH-PRESSURE PARTICULATE CONTROL PROGRAMS
The report describes and compares current projects sponsored by EPA and the U.S. Energy Research and Development Administration (ERDA), relating to the control of particulate matter in fuel gas streams at high temperatures (1000 to 2000F) and high pressures (5 atm and greater). T...
Yanamala, Naveena; Hatfield, Meghan K.; Farcas, Mariana T.; Schwegler-Berry, Diane; Hummer, Jon A.; Shurin, Michael R.; Birch, M. Eileen; Gutkin, Dmitriy W.; Kisin, Elena; Kagan, Valerian E.; Bugarski, Aleksandar D.; Shvedova, Anna A.
2015-01-01
The use of biodiesel (BD) or its blends with petroleum diesel (D) is considered to be a viable approach to reduce occupational and environmental exposures to particulate matter (PM). Due to its lower particulate mass emissions compared to D, use of BD is thought to alleviate adverse health effects. Considering BD fuel is mainly composed of unsaturated fatty acids, we hypothesize that BD exhaust particles could induce pronounced adverse outcomes, due to their ability to readily oxidize. The main objective of this study was to compare the effects of particles generated by engine fueled with neat BD and neat petroleum-based D. Biomarkers of tissue damage and inflammation were significantly elevated in lungs of mice exposed to BD particulates. Additionally, BD particulates caused a significant accumulation of oxidatively modified proteins and an increase in 4-hydroxynonenal. The up-regulation of inflammatory cytokines/chemokines/growth factors was higher in lungs upon BD particulate exposure. Histological evaluation of lung sections indicated presence of lymphocytic infiltrate and impaired clearance with prolonged retention of BD particulate in pigment laden macrophages. Taken together, these results clearly indicate that BD exhaust particles could exert more toxic effects compared to D. PMID:23886933
Particulate generation and control in the PREPP (Process Experimental Pilot Plant) incinerator
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stermer, D.L.; Gale, L.G.
1989-03-01
Particulate emissions in radioactive incineration systems using a wet scrubbing system are generally ultimately controlled by flowing the process offgas stream through a high-efficiency filter, such as a High Efficient Particulate Air (HEPA) filter. Because HEPA filters are capable of reducing particulate emissions over an order of magnitude below regulatory limits, they consequently are vulnerable to high loading rates. This becomes a serious handicap in radioactive systems when filter change-out is required at an unacceptably high rate. The Process Experimental Pilot Plant (PREPP) incineration system is designed for processing retrieved low level mixed hazardous waste. It has a wet offgasmore » treatment system consisting of a Quencher, Venturi Scrubber, Entrainment Eliminator, Mist Eliminator, two stages of HEPA filters, and induced draft fans. During previous tests, it was noted that the offgas filters loaded with particulate at a rate requiring replacement as often as every four hours. During 1988, PREPP conducted a series of tests which included an investigation of the causes of heavy particulate accumulation on the offgas filters in relation to various operating parameters. This was done by measuring the particulate concentrations in the offgas system, primarily as a function of scrub solution salt concentration, waste feed rate, and offgas flow rate. 2 figs., 9 tabs.« less
Guan, Bin; Zhan, Reggie; Lin, He; Huang, Zhen
2015-05-01
The increasingly stringent emission regulations, such as US 2010, Tier 2 Bin 5 and beyond, off-road Tier 4 final, and Euro V/5 for particulate matter (PM) reduction applications, will mandate the use of the diesel particulate filters (DPFs) technology, which is proven to be the only way that can effectively control the particulate emissions. This paper covers a comprehensive overview of the state-of-the-art DPF technologies, including the advanced filter substrate materials, the novel catalyst formulations, the highly sophisticated regeneration control strategies, the DPF uncontrolled regenerations and their control methodologies, the DPF soot loading prediction, and the soot sensor for the PM on-board diagnostics (OBD) legislations. Furthermore, the progress of the highly optimized hybrid approaches, which involves the integration of diesel oxidation catalyst (DOC) + (DPF, NOx reduction catalyst), the selective catalytic reduction (SCR) catalyst coated on DPF, as well as DPF in the high-pressure exhaust gas recirculation (EGR) loop systems, is well discussed. Besides, the impacts of the quality of fuel and lubricant on the DPF performance and the maintenance and retrofit of DPF are fully elaborated. Meanwhile, the high efficiency gasoline particulate filter (GPF) technology is being required to effectively reduce the PM and particulate number (PN) emissions from the gasoline direct injection (GDI) engines to comply with the future increasingly stricter emissions regulations. Copyright © 2015 Elsevier Ltd. All rights reserved.
Population exposure to ambient particulate matter (PM) has received considerable attention due to the association between ambient particulate concentrations and mortality. Current toxicological and epidemiological studies and controlled human and animal exposures suggest that a...
The Baumot BA-B Diesel Particulate Filter with Pre-Catalyst is a diesel engine retrofit device for light, medium, and heavy heavy-duty diesel on-highway engines for use with commercial ultra-low-sulfur diesel (ULSD) fuel. The BA-B particulate filter is composed of a pre-catalyst ...
Advanced particulate matter control apparatus and methods
Miller, Stanley J [Grand Forks, ND; Zhuang, Ye [Grand Forks, ND; Almlie, Jay C [East Grand Forks, MN
2012-01-10
Apparatus and methods for collection and removal of particulate matter, including fine particulate matter, from a gas stream, comprising a unique combination of high collection efficiency and ultralow pressure drop across the filter. The apparatus and method utilize simultaneous electrostatic precipitation and membrane filtration of a particular pore size, wherein electrostatic collection and filtration occur on the same surface.
The purpose of this SOP is to describe the in-field use of the particulate sampling system (pumping, control unit, and size selective inlet impactors) for collecting samples of particulate matter from the air during a predetermined time period during the Arizona NHEXAS project an...
Lu, Xingcheng; Lin, Changqing; Li, Ying; Yao, Teng; Fung, Jimmy C H; Lau, Alexis K H
2017-01-01
As the major engine of economic growth in China, the Pearl River Delta (PRD) region is one of the most urbanized regions in the world. Rapid development has brought great wealth to its citizens; however, at the same time, increasing emissions of ambient pollutants from vehicles and industrial combustions have caused considerable air pollution and negative health effects for the region's residents. In this study, the concentration response function method was applied together with satellite-retrieved particulate matter (PM 10 and PM 2.5 ) concentration data to estimate the health burden caused by this pollutant from 2004 to 2013. The value of statistical life was used to calculate the economic loss due to the negative health effects of particulate matter pollution. Our results show that in the whole PRD region, the estimated number of deaths from the four diseases attributable to PM 2.5 was the highest in 2012, at 45,000 (19,000-61,000); the number of all-cause hospital admissions due to PM 10 was the highest in 2013, reaching up to 91,000 (0-270,000) (excluding Hong Kong). Among the 10 cities, the capital city Guangzhou suffered the most from ambient particulate matter pollution and had the highest mortality and morbidity over the 10years. The cost of mortality in this region was the highest in 2012, at 46,000 million USD, or around 6.1% of local total gross domestic product (GDP). The positive spatial relationship between the degree of urbanization and the particulate matter concentration proves that the urbanization process does worsen air quality and hence increases the health risks of local urban citizens. It is recommended that local governments further enhance their control policies to better guarantee the health and wealth benefits of local residents. Copyright © 2016 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Eastham, Sebastian D.; Barrett, Steven R. H.
2016-11-01
Aviation is a significant source of tropospheric ozone, which is a critical UV blocking agent, an indirect precursor to the formation of particulate matter, and a respiratory health hazard. To date, investigations of human health impacts related to aviation emissions have focused on particulate matter, and no global estimate yet exists of the combined health impact of aviation due to ozone, particulate matter and UV exposure changes. We use a coupled tropospheric-stratospheric chemical-transport model with a global aviation emissions inventory to estimate the total impact of aviation on all three risk factors. We find that surface ozone due to aviation emissions is maximized during hemispheric winter due to the greater wintertime chemical lifetime of ozone, but that a smaller enhancement of 0.5 ppbv occurs during summertime. This summertime increase results in an estimated 6,800 premature mortalities per year due to ozone exposure, over three times greater than previous estimates. During the winter maximum, interaction with high background NOx concentrations results in enhanced production of nitrate aerosol and increased annual average exposure to particulate matter. This ozone perturbation is shown to be the driving mechanism behind an additional 9,200 premature mortalities due to exposure to particulate matter. However, the increase in tropospheric ozone is also found to result in 400 fewer mortalities due to melanoma skin cancer in 2006. This is the first estimate of global melanoma mortality due to aviation, and the first estimate of skin cancer mortality impacts due to aviation using a global chemical transport model.
Thermoelectric properties of hot-pressed fine particulate powder SiGe alloys
NASA Technical Reports Server (NTRS)
Beaty, John S.; Rolfe, Jonathan; Vandersande, Jan
1991-01-01
A novel material system and its fabrication technique have been defined and applied to the production of SiGe thermoelectric material through the hot pressing of 50-100 A ultrafine particulates into 80/20 SiGe. Relative to conventionally processed SiGe, a reduction of thermal conductivity of up to 40 percent is achieved in conjunction with an enhancement of material figure-of-merit of the order of 10-15 percent.
Improved Electronic Control for Electrostatic Precipitators
NASA Technical Reports Server (NTRS)
Johnston, D. F.
1986-01-01
Electrostatic precipitators remove particulate matter from smoke created by burning refuse. Smoke exposed to electrostatic field, and particles become electrically charged and migrate to electrically charged collecting surfaces. New microprocessor-based electronic control maintains precipitator power at maximum particulate-collection level. Control automatically senses changes in smoke composition due to variations in fuel or combustion and adjusts precipitator voltage and current accordingly. Also, sensitive yet stable fault detection provided.
Infiltration processing of metal matrix composites using coated ceramic particulates
NASA Astrophysics Data System (ADS)
Leon-Patino, Carlos Alberto
2001-07-01
A new process was developed to fabricate particulate metal matrix composites (MMCs). The process involves three steps: (1) modifying the particulate surface by metal coating, (2) forming a particulate porous compact; and (3) introducing metal into the channel network by vacuum infiltration. MMCs with different reinforcements, volume fractions, and sizes can be produced by this technique. Powders of alumina and silicon carbide were successfully coated with nickel and copper in preparation for infiltration with molten aluminum. Electroless Ni and Cu deposition was used since it enhances the wettability of the reinforcements for composite fabrication. While Cu deposits were polycrystalline, traces of phosphorous co-deposited from the electroless bath gave an amorphous Ni-P coating. The effect of metal coating on wetting behavior was evaluated at 800°C on plain and metal-coated ceramic plates using a sessile drop technique. The metallic films eliminated the non-wetting behavior of the uncoated ceramics, leading to equilibrium contact angles in the order of 12° and below 58° for Ni and Cu coated ceramics, respectively. The spreading data indicated that local diffusion at the triple junction was the governing mechanism of the wetting process. Precipitation of intermetallic phases in the drop/ceramic interface delayed the formation of Al4C3. Infiltration with molten Al showed that the coated-particulates are suitable as reinforcing materials for fabricating MMCs, giving porosity-free components with a homogeneously distributed reinforcing phase. The coating promoted easy metal flow through the preform, compared to the non-infiltration behavior of the uncoated counterparts. Liquid state diffusion kinetics due to temperature dependent viscosity forces controlled the infiltration process. Microstructural analysis indicated the formation of intermetallic phases such as CuAl 2, in the case of Cu coating, and Ni2Al3 and NiAl 3 when Ni-coated powders were infiltrated. The overall Ni and Cu content increased from bottom to top of the samples due to dissolution of the metal film by the stream of liquid Al during infiltration. The strengths of the Al/Ni-SiC composites, measured by four-point bending, were 205 and 225 MPa for samples reinforced with 78 mum and 49 mum Ni-SiC, respectively. The mode of fracture was mainly controlled by SiC particle fracture.
Dunn, James E; Davis, Wayne T; Calcagno, James A; Allen, Marshall W
2002-01-01
A field study to evaluate the performance of three commercially available particulate matter (PM) continuous emission monitors (CEMs) was conducted in 1999-2000 at the US Department of Energy (DOE) Toxic Substances Control Act (TSCA) Incinerator. This study offers unique features that are believed to enhance the collective US experience with PM CEMs. The TSCA Incinerator is permitted to treat PCB-contaminated RCRA hazardous low-level radioactive wastes. The air pollution control system utilizes MACT control technology and is comprised of a rapid quench, venturi scrubber, packed bed scrubber, and two ionizing wet scrubbers in series, which create a saturated flue gas that must be conditioned by the CEMs prior to measurement. The incinerator routinely treats a wide variety of wastes including high and low BTU organic liquids, aqueous, and solid wastes. The various possible combinations for treating liquid and solid wastes may present a challenge in establishing a single, acceptable correlation relationship for individual CEMs. The effect of low-level radioactive material present in the waste is a unique site-specific factor not evaluated in previous tests. The three systems chosen for evaluation were two beta gauge devices and a light scattering device. The performance of the CEMs was evaluated using the requirements in draft Environmental Protection Agency (EPA) Performance Specification 11 (PS11) and Procedure 2. The results of Reference Method 5i stack tests for establishing statistical correlations between the reference method data and the CEMs responses are discussed.
Toxicity of used drilling fluids to mysids (Mysidopsis bahia)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gaetz, C.T.; Montgomery, R.; Duke, T.W.
1986-01-01
Static, acute toxicity tests were conducted with mysids (Mysidopsis bahia) and 11 used drilling fluids (also called drilling muds) obtained from active drilling platforms in the Gulf of Mexico, U.S.A. Each whole mud was tested, along with three phases of each mud: a liquid phase with all particulate materials removed; a suspended particulate phase composed of soluble and lighter particulate fractions; and a solid phase composed mainly of drill cuttings and rapidly settling particulates. These muds represented seven of the eight generic mud types described by the U.S. Environmental Protection Agency for use on the U.S. Outer Continental Shelf. Themore » toxicity of the 11 muds tested was apparently enhanced by the presence of aromatics. Furthermore, one mud tested repeatedly showed loss of toxicity with time, possibly from volatilization of aromatic fractions. The data demonstrated that aromatics in the drilling fluids affected their toxicity to M. bahia.« less
NASA Astrophysics Data System (ADS)
Gérin, C.; Goutx, M.
1994-08-01
The Chromarod-Iatroscan system was used to measure dissolved and particulate lipids at six sites representative of the main hydrological zones of the Almeria-Oran frontal system in May 1991. Concentrations ranged from 9 to 113 μg 1 -1 and from 3 to 84 μg 1 -1 respectively. Particulate carbon was estimated on a CHN Leco analyzer. Dissolved lipid concentrations were highly variable with depth and exhibited clear signatures of phytoplankton degradation throughout the profiles. In the 300-400 m layer, particulate wax esters denoted the presence of deep zooplankton which may be benefit from the downward fluxes of organic matter from the frontal zone. In surface water, high concentrations of dissolved lipids and particulate carbon marked the presence of the jet front. Particulate lipid classes in samples were related to the presence of zooplankton and to the physiological state of cells rather than to phytoplankton biomass. Particulate triglyceride concentrations (storage lipids in phytoplankton) increased from the left to the right border of the jet core and further southwards, culminating in the Atlantic anticyclonic gyre. The distribution of particulate lipids to carbon and chlorophyllatios and the increasing level of triglycerides from the jet and southwards suggested a rapid removal of the frontal production by physical transports. The ability of anticyclonic structures to enhance accumulations of energetically rich compounds and thus to play a role as fertilizers of the oligotrophic waters of the Mediterranean Sea is discussed.
USDA-ARS?s Scientific Manuscript database
Particulate matter (PM) is a major air pollutant emitted from animal production and has significant impacts on health and the environment. Abatement of PM emissions is imperative and effective PM control technologies are strongly needed. In this work, an electrostatic spray wet scrubber (ESWS) techn...
40 CFR 52.126 - Control strategy and regulations: Particulate matter.
Code of Federal Regulations, 2013 CFR
2013-07-01
.... Therefore, Regulation 7-1-3.6 (process industries) of the Arizona Rules and Regulations for Air Pollution... regulation for Regulation 7-1-3.6 of the Arizona Rules and Regulations for Air Pollution Control (Gila... regulation 7-3-1.7 (Particulate Emissions—Fuel Burning Equipment) of the Rules and Regulations for Pinal-Gila...
40 CFR 52.126 - Control strategy and regulations: Particulate matter.
Code of Federal Regulations, 2012 CFR
2012-07-01
.... Therefore, Regulation 7-1-3.6 (process industries) of the Arizona Rules and Regulations for Air Pollution... regulation for Regulation 7-1-3.6 of the Arizona Rules and Regulations for Air Pollution Control (Gila... regulation 7-3-1.7 (Particulate Emissions—Fuel Burning Equipment) of the Rules and Regulations for Pinal-Gila...
40 CFR 52.126 - Control strategy and regulations: Particulate matter.
Code of Federal Regulations, 2014 CFR
2014-07-01
.... Therefore, Regulation 7-1-3.6 (process industries) of the Arizona Rules and Regulations for Air Pollution... regulation for Regulation 7-1-3.6 of the Arizona Rules and Regulations for Air Pollution Control (Gila... regulation 7-3-1.7 (Particulate Emissions—Fuel Burning Equipment) of the Rules and Regulations for Pinal-Gila...
To what extent can biogenic SOA be controlled?
Carlton, Annmarie G; Pinder, Robert W; Bhave, Prakash V; Pouliot, George A
2010-05-01
The implicit assumption that biogenic secondary organic aerosol (SOA) is natural and can not be controlled hinders effective air quality management. Anthropogenic pollution facilitates transformation of naturally emitted volatile organic compounds (VOCs) to the particle phase, enhancing the ambient concentrations of biogenic secondary organic aerosol (SOA). It is therefore conceivable that some portion of ambient biogenic SOA can be removed by controlling emissions of anthropogenic pollutants. Direct measurement of the controllable fraction of biogenic SOA is not possible, but can be estimated through 3-dimensional photochemical air quality modeling. To examine this in detail, 22 CMAQ model simulations were conducted over the continental U.S. (August 15 to September 4, 2003). The relative contributions of five emitted pollution classes (i.e., NO(x), NH(3), SO(x), reactive non methane carbon (RNMC) and primary carbonaceous particulate matter (PCM)) on biogenic SOA were estimated by removing anthropogenic emissions of these pollutants, one at a time and all together. Model results demonstrate a strong influence of anthropogenic emissions on predicted biogenic SOA concentrations, suggesting more than 50% of biogenic SOA in the eastern U.S. can be controlled. Because biogenic SOA is substantially enhanced by controllable emissions, classification of SOA as biogenic or anthropogenic based solely on VOC origin is not sufficient to describe the controllable fraction.
Radio Frequency Sensing of Particulate Matter Accumulation on a Gasoline Particulate Filter
DOE Office of Scientific and Technical Information (OSTI.GOV)
Parks, James; Prikhodko, Vitaly Y.; Sappok, Alex
Filter Sensing Technology’s radio frequency (RF) sensor for particulate filter on-board diagnostics (OBD) was studied on a lean gasoline engine at the National Transportation Research Center (NTRC) at Oak Ridge National Laboratory (ORNL). The response of the RF sensor to particulate matter (PM) or “soot” accumulation on the gasoline particulate filter (GPF) installed in the engine exhaust was evaluated. In addition, end plugs of the GPF were purposely removed, and subsequent changes to the RF sensor measured soot loading on the GPF were characterized. Results from the study showed that the RF sensor can accurately measure soot accumulation on amore » GPF; furthermore, the predicted decreased soot accumulation due to plug removal was detected by the RF sensor. Overall, the studies were short and preliminary in nature; however, clearly, the RF sensor demonstrated the capability of measuring GPF soot loading at a level suitable for use in lean gasoline engine emission control OBD and control.« less
Healing of rabbit calvarial critical-sized defects using autogenous bone grafts and fibrin glue.
Lappalainen, Olli-Pekka; Korpi, Riikka; Haapea, Marianne; Korpi, Jarkko; Ylikontiola, Leena P; Kallio-Pulkkinen, Soili; Serlo, Willy S; Lehenkari, Petri; Sándor, George K
2015-04-01
This study aimed to evaluate ossification of cranial bone defects comparing the healing of a single piece of autogenous calvarial bone representing a bone flap as in cranioplasty compared to particulated bone slurry with and without fibrin glue to represent bone collected during cranioplasty. These defect-filling materials were then compared to empty control cranial defects. Ten White New Zealand adult male rabbits had bilateral critical-sized calvarial defects which were left either unfilled as control defects or filled with a single full-thickness piece of autogenous bone, particulated bone, or particulated bone combined with fibrin glue. The defects were left to heal for 6 weeks postoperatively before termination. CT scans of the calvarial specimens were performed. Histomorphometric assessment of hematoxylin-eosin- and Masson trichrome-stained specimens was used to analyze the proportion of new bone and fibrous tissue in the calvarial defects. There was a statistically significant difference in both bone and soft tissue present in all the autogenous bone-grafted defect sites compared to the empty negative control defects. These findings were supported by CT scan findings. While fibrin glue combined with the particulated bone seemed to delay ossification, the healing was more complete compared to empty control non-grafted defects. Autogenous bone grafts in various forms such as solid bone flaps or particulated bone treated with fibrin glue were associated with bone healing which was superior to the empty control defects.
SYNTHETIC PARTICLES ENHANCE AIRWAY RESPONSES TO OVALBUMIN ANTIGEN IN BALB/C MICE
SYNTHETIC PARTICLES ENHANCE AIRWAY RESPONSES TO OVALBUMIN ANTIGEN IN BALB/CJ MICE. S H Gavett, N Haykal-Coates, and M I Gilmour. Experimental Toxicology Division, NHEERL, ORD, USEPA, Research Triangle Park, NC
Levels of airborne particulate matter (PM) are positively c...
Influenza virus infection in mice after exposure to coal dust and diesel engine emissions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hahon, N.; Booth, J.A.; Green, F.
1985-06-01
Influenza virus infection initiated after aerosol exposure of CD-1, white Swiss mice for durations of 1, 3, and 6 months to respirable particulates maintained at 2 mg/m3 of either coal dust (CD), diesel engine emissions (DEE), a combination of both (CD/DEE), or to filtered air (control) was studied. The course of infection in mice previously exposed for 1 month to various particulates did not differ appreciably among the four animal groups with respect to mortality, virus growth in lungs, interferon levels, or hemagglutinin antibody response. In mice exposed for 3 and 6 months to different particulates, the mortality response wasmore » similar among all animal groups. However, the percentage of animals showing lung consolidation was significantly higher in the 3-month groups exposed to DEE (96.5%) and CD/DEE (97%) than in the control (61.2%); in the 6-month groups, the percentages were twice that of the control for both DEE- and CD/DEE-exposed animals. Complementing these observations of both 3- and 6-month-exposed animals was the higher virus growth levels attained in the DEE and CD/DEE animals with concomitant depressed interferon levels which were the inverse of findings noted in the control group. Hemagglutinin-antibody levels in particulate-exposed animals, especially at the 6-month interval, were fourfold less than the control. Histopathologic examination of lungs revealed no qualitative differences in the inflammatory response at any one specified time interval of exposure to influenza virus among the control and particulate-exposed animal groups. However, there were differences in severity of reaction in relation to the particulate component of the exposures. Focal macular collections of pigment-laden macrophages were seen only in DEE and CD/DEE but not in CD animals after 3- and 6-month exposures.« less
Methods for providing ceramic matrix composite components with increased thermal capacity
NASA Technical Reports Server (NTRS)
Steibel, James Dale (Inventor); Utah, David Alan (Inventor)
2001-01-01
A method for enhancing the cooling capability of a turbine component made from a ceramic matrix composite. The method improves the thermal performance of the component by producing a surface having increased cooling capacity, thereby allowing the component to operate at a higher temperature. The method tailors the available surface area on the cooling surface of the composite component by depositing a particulate layer of coarse grained ceramic powders of preselected size onto the surface of the ceramic matrix composite component. The size of the particulate is selectively tailored to match the desired surface finish or surface roughness of the article. The article may be designed to have different surface finishes for different locations, so that the application of different sized powders can provide different cooling capabilities at different locations, if desired. The compositions of the particulates are chemically compatible with the ceramic material comprising the outer surface or portion of the ceramic matrix composite. The particulates are applied using a slurry and incorporated into the article by heating to an elevated temperature without melting the matrix, the particulates or the fiber reinforcement.
Fuel-Burning Technology Alternatives for the Army.
1985-01-01
control 0.85 2,287,000 Flue gas desulfurization 0.68 3,410,000 Total 12,478,000 *Capital cost estimate...34......... . . Particulate and sulfur dioxide control are needed. A baghouse and flue gas desulfurization (FD) scrubber system must be installed. Each item’s cost in...direct cost) Contingency (20% of 1,253,000 direct and indirect costs) Subtotal 7,518,000 Particulate control 1,342,000 Flue gas desulfurization
Electrically heated particulate matter filter soot control system
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gonze, Eugene V.; Paratore, Jr., Michael J.; Bhatia, Garima
A regeneration system includes a particulate matter (PM) filter with an upstream end for receiving exhaust gas and a downstream end. A control module determines a current soot loading level of the PM filter and compares the current soot loading level to a predetermined soot loading level. The control module permits regeneration of the PM filter when the current soot loading level is less than the predetermined soot loading level.
Enhanced hydrophilicity of chlorided aluminum oxide particulates
NASA Technical Reports Server (NTRS)
Cofer, W. R., III
1978-01-01
An enhancement of hydrophilicity for chlorided aluminas was demonstrated by the results obtained from gaseous H2O sorptions at 70-, 80-, and 86-percent relative humidity on alpha and gamma aluminum oxide particulates and on alpha and gamma aluminum oxide particulates with a chemisorbed surface chloride phase (produced by reactions of gaseous HCl + H2O on alumina). Continuous sorption histories for H2O on chlorided aluminas having specific surface areas that range from 7 to 227 sq m/g before chloriding indicated that initial sorption rates were directly linked to the extent of chemisorbed chlorided coverage and implied the same relationship for sorption capacities. The initial sorption rate on chlorided aluminas was found to be slower for the first exposure to H2O than for subsequent exposures (which reached equilibrated H2O coverages much faster), suggesting that slow chemical reactions between H2O and chlorided alumina may have been operative during initial exposures. Chlorided alumina particles were found to remain very hydrophilic (relative to nonchlorided analogs) for several H2O sorption/desorption cycles.
Microwave-enhanced chemical processes
Varma, Ravi
1990-01-01
A process for disposal of toxic wastes including chlorinated hydrocarbons, comprising, establishing a bed of non-metallic particulates having a high dielectric loss factor. Effecting intimate contact of the particulates and the toxic wastes at a temperature in excess of about 400.degree. C. in the presence of microwave radiation for a time sufficient to break the hydrocarbon chlorine bonds and provide detoxification values in excess of 80 and further detoxifying the bed followed by additional disposal of toxic wastes.
Inspection of lithographic mask blanks for defects
Sommargren, Gary E.
2001-01-01
A visible light method for detecting sub-100 nm size defects on mask blanks used for lithography. By using optical heterodyne techniques, detection of the scattered light can be significantly enhanced as compared to standard intensity detection methods. The invention is useful in the inspection of super-polished surfaces for isolated surface defects or particulate contamination and in the inspection of lithographic mask or reticle blanks for surface defects or bulk defects or for surface particulate contamination.
Systems and methods for controlling diesel engine emissions
Webb, Cynthia Chaffin; Weber, Phillip Anthony; Khair, Magdi K.
2004-06-01
Systems and methods for controlling diesel engine emissions, including, for example, oxides of nitrogen emissions, particulate matter emissions, and the like. The emission control system according to this invention is provided in the exhaust passageway of a diesel engine and includes a catalyst-based particulate filter; and first and second lean NO.sub.x trap systems coupled to the catalyst-based particulate filter. The first and second lean NO.sub.x trap systems are arranged in a parallel flow configuration with each other. Each of the first and second lean NO.sub.x trap systems include a carbon monoxide generating catalyst device, a sulfur trap device, a lean NO.sub.x device, a supplemental fuel injector device, and a plurality of flow diverter devices.
Baalousha, Mohamed; Stoll, Serge; Motelica-Heino, Mikaël; Guigues, Nathalie; Braibant, Gilles; Huneau, Frédéric; Le Coustumer, Philippe
2018-02-10
This study investigates the spatiotemporal variability of major and trace elements, dissolved organic carbon (DOC), total dissolved solids (TDS), and suspended particulate matter (SPM) in surface waters of several hydrosystems of the Loire River watershed in France. In particular, this study aims to delineate the impact of the abovementioned water physicochemical parameters on natural iron and manganese physical speciation (homoaggregation/heteroaggregation) among fine colloidal and dissolved (< 10 nm), colloidal (10-450 nm) and particulate (> 450 nm) phases in Loire River watershed. Results show that the chemistry of the Loire River watershed is controlled by two end members: magmatic and metamorphic petrographic context on the upper part of the watershed; and sedimentary rocks for the middle and low part of the Loire. The percentage of particulate Fe and Mn increased downstream concurrent with the increase in SPM and major cations concentration, whereas the percentage of colloidal Fe and Mn decreased downstream. Transmission electron microscopy analyses of the colloidal and particulate fractions (from the non-filtered water sample) revealed that heteroaggregation of Fe and Mn rich natural nanoparticles and natural organic matter to the particulate phase is the dominant mechanism. The heteroaggregation controls the partitioning of Fe and Mn in the different fractions, potentially due to the increase in the ionic strength, and divalent cations concentration downstream, and SPM concentration. These findings imply that SPM concentration plays an important role in controlling the fate and behavior of Fe and Mn in various sized fractions. Graphical abstract Physical speciation by heteroaggregation of (Fe-Mn) compounds: high [SPM] → [Fe-Mn] particulate faction; low {SPM] → [Fe-Mn] colloid-dissolved fraction.
Karelin, A O; Lomtev, A Yu; Mozzhukhina, N A; Yeremin, G B; Nikonov, V A
Inhalation of fine particulate matters (PM and PM ) poses a threat for the health of population. Purpose of the study the analysis of the monitoring of fine particulate matters in the atmospheric air of Saint-Petersburg and identification of the main problems of the monitoring. Research methods methods of scientific hypothetical deductive cognition, sanitary-statistical methods, general logical methods and approaches of researches: analysis, synthesis, abstracting, generalization, induction. Results. The article represents the analysis of the monitoring of fine particulate matters in the atmospheric air of Saint- Petersburg. Only 11 in automatic monitoring stations out of 22 there is carried out the control of fine particulate matters: in 7 - PM and PM, and in 4 - PM The average year concentrations were below MAC in all the stations. The maximum concentrations achieved 3 MAC, but the repeatance of cases of exceedence of concentrations more than MAC was very rare. On the average of the city concentrations of PM were decreased from 0,8 MAC in 2006 and 1,1 MAC in 2007 to 0,5 MAC in 2013-14. The executed analysis revealed main problems of the monitoring of fine particulate matters in the Russian Federation. They include the absence of the usage 1of the officially approved methods of controlling of PM and PM in the atmospheric air until March 1, 2016, lack of the modern equipment for measurement of fine particulate matters. Conclusions. Therefore, the state of the monitoring of fine particulate matters in the atmospheric air in the Russian Federation fails to be satisfactory. It is necessary to improve system of the monitoring, create modern Russian appliances, methods and means for measurement of fine particulate matters concentrations in the atmospheric air.
40 CFR 52.776 - Control strategy: Particulate matter.
Code of Federal Regulations, 2010 CFR
2010-07-01
... Approval—The complete Indiana plan for Clark, Dearborn, Dubois, Marion (except for coke batteries), St..., Vandenburgh County; 6-1-17, Clark County; 6-1-18, St. Joseph County; 6-2, Particulate Emissions Limitations...
40 CFR 52.776 - Control strategy: Particulate matter.
Code of Federal Regulations, 2011 CFR
2011-07-01
... Approval—The complete Indiana plan for Clark, Dearborn, Dubois, Marion (except for coke batteries), St..., Vandenburgh County; 6-1-17, Clark County; 6-1-18, St. Joseph County; 6-2, Particulate Emissions Limitations...
Baysal, Asli; Saygin, Hasan; Ustabasi, Gul Sirin
2017-12-21
A significant knowledge gap in nanotechnology is the absence of standardized protocols for examining and comparison the effect of metal oxide nanoparticles on different environment media. Despite the large number of studies on ecotoxicity of nanoparticles, most of them disregard the particles physicochemical transformation under real exposure conditions and interaction with different environmental components like air, soil, water, etc. While one of the main exposure ways is inhalation and/or atmosphere for human and environment, there is no investigation between airborne particulates and nanoparticles. In this study, some metal oxide nanoparticle (ZnO and TiO 2 ) transformation and behavior in PM2.5 air particulate media were examined and evaluated by the influence on nanoparticle physicochemical properties (size, surface charge, surface functionalization) and on bacterium (Gram-positive Bacillus subtilis, Staphylococcus aureus/Gram-negative Escherichia coli, Pseudomonas aeruginosa bacteria) by testing in various concentrations of PM2.5 airborne particulate media to contribute to their environmental hazard and risk assessment in atmosphere. PM2.5 airborne particulate media affected their toxicity and physicochemical properties when compared the results obtained in controlled conditions. ZnO and TiO 2 surfaces were functionalized mainly with sulfoxide groups in PM2.5 air particulates. In addition, tested particles were not observed to be toxic in controlled conditions. However, these were observed inhibition in PM2.5 airborne particulates media by the exposure concentration. These observations and dependence of the bacteria viability ratio explain the importance of particulate matter-nanoparticle interaction.
Microwave-enhanced chemical processes
Varma, R.
1990-06-19
A process is disclosed for the disposal of toxic wastes including chlorinated hydrocarbons, comprising, establishing a bed of non-metallic particulates having a high dielectric loss factor. Intimate contact of the particulates and the toxic wastes at a temperature in excess of about 400 C in the presence of microwave radiation for a time sufficient breaks the hydrocarbon chlorine bonds. Detoxification values in excess of 80 are provided and further detoxification of the bed is followed by additional disposal of toxic wastes. 1 figure.
The proceedings document the Third U.S./U.S.S.R. Symposium on Particulate Control, September 10-12, 1979, in Suzdal, U.S.S.R. Papers covered such topics as: predicting back-corona formation and fly ash resistivity, improved electrostatic precipitator (ESP) mathematical modeling, ...
Cyclone separator having boundary layer turbulence control
Krishna, Coimbatore R.; Milau, Julius S.
1985-01-01
A cyclone separator including boundary layer turbulence control that is operable to prevent undue build-up of particulate material at selected critical areas on the separator walls, by selectively varying the fluid pressure at those areas to maintain the momentum of the vortex, thereby preventing particulate material from inducing turbulence in the boundary layer of the vortical fluid flow through the separator.
Koo, Ki-Tae; Susin, Cristiano; Wikesjö, Ulf M E; Choi, Seong-Ho; Kim, Chong-Kwan
2007-04-01
In a previous study, recombinant human transforming growth factor-beta1 (rhTGF-β 1 ) in a calcium carbonate carrier was implanted into critical-size, supraalveolar periodontal defects under conditions for guided tissue regeneration (GTR) to study whether rhTGF-β 1 would enhance or accelerate periodontal regeneration. The results showed minimal benefits of rhTGF-β 1 , and a clear account for this could not be offered. One potential cause may be that the rhTGF-β 1 formulation was biologically inactive. Several growth or differentiation factors have been suggested to accelerate degradation of biomaterials used as carriers. The objective of this study was to evaluate possible activity of rhTGF-β 1 on biodegradation of the calcium carbonate carrier. rhTGF-β 1 in a putty-formulated particulate calcium carbonate carrier was implanted into critical-size, supraalveolar periodontal defects under conditions for GTR in five beagle dogs. Contralateral defects received the calcium carbonate carrier combined with GTR without rhTGF-β 1 (control). The animals were euthanized at week 4 post-surgery and block biopsies of the defect sites were collected for histologic and histometric analysis. Radiographs were obtained at defect creation and weeks 2 and 4 after defect creation. No statistically significant differences were observed in new bone formation (bone height and area) among the treatments. However, total residual carrier was significantly reduced in sites receiving rhTGF-β 1 compared to control (P = 0.04). Similarly, carrier density was considerably reduced in sites receiving rhTGF-β 1 compared to control; the difference was borderline statistically significant (P = 0.06). Within the limitations of the study, it may be concluded that rhTGF-β 1 accelerates biodegradation of a particulate calcium carbonate biomaterial, indicating a biologic activity of the rhTGF-β 1 formulation apparently not encompassing enhanced or accelerated periodontal regeneration. © 2007 American Academy of Periodontology.
Koo, Ki-Tae; Susin, Cristiano; Wikesjö, Ulf M E; Choi, Seong-Ho; Kim, Chong-Kwan
2007-04-01
In a previous study, recombinant human transforming growth factor-beta1 (rhTGF-beta(1)) in a calcium carbonate carrier was implanted into critical-size, supraalveolar periodontal defects under conditions for guided tissue regeneration (GTR) to study whether rhTGF-beta(1) would enhance or accelerate periodontal regeneration. The results showed minimal benefits of rhTGF-beta(1), and a clear account for this could not be offered. One potential cause may be that the rhTGF-beta(1) formulation was biologically inactive. Several growth or differentiation factors have been suggested to accelerate degradation of biomaterials used as carriers. The objective of this study was to evaluate possible activity of rhTGF-beta(1) on biodegradation of the calcium carbonate carrier. rhTGF-beta(1) in a putty-formulated particulate calcium carbonate carrier was implanted into critical-size, supraalveolar periodontal defects under conditions for GTR in five beagle dogs. Contralateral defects received the calcium carbonate carrier combined with GTR without rhTGF-beta(1) (control). The animals were euthanized at week 4 post-surgery and block biopsies of the defect sites were collected for histologic and histometric analysis. Radiographs were obtained at defect creation and weeks 2 and 4 after defect creation. No statistically significant differences were observed in new bone formation (bone height and area) among the treatments. However, total residual carrier was significantly reduced in sites receiving rhTGF-beta(1) compared to control (P = 0.04). Similarly, carrier density was considerably reduced in sites receiving rhTGF-beta(1) compared to control; the difference was borderline statistically significant (P = 0.06). Within the limitations of the study, it may be concluded that rhTGF-beta(1) accelerates biodegradation of a particulate calcium carbonate biomaterial, indicating a biologic activity of the rhTGF-beta(1) formulation apparently not encompassing enhanced or accelerated periodontal regeneration.
Gastric emptying of multi-particulate dosage forms.
Newton, J Michael
2010-08-16
The evidence in the literature for the concept that multi-particulate dosage forms below a specific size empty from the stomach as if they were liquids and hence have the potential to provide the best solution to the formulation of controlled release oral dosage forms, has been considered. There is some evidence that particles less than 1.0mm provide a more rapid response than larger size particles but there is also evidence that this is not always the case and that rapid and reproducible gastric emptying of small particles does not always occur when they are administered. There is strong evidence that food can delay the gastric emptying of multi-particulate systems. Some of the misconception for gastric emptying performance of multi-particulate system is shown to be related to the limitation of the study design and limitation of the way the data is processed. Nevertheless, there is clear evidence that multi-particulate systems can provide effective oral controlled release dosage forms. There is still some way to go with experimental techniques which would allow a definitive answer to the issue of how the variability of the gastric emptying of multi-particulate systems of less than 2.0mm arises. Copyright (c) 2010 Elsevier B.V. All rights reserved.
Lack of enhanced photocatalytic formation of iodine on particulate semiconductor mixtures.
Karunakaran, C; Anilkumar, P; Vinayagamoorthy, P
2012-12-01
Under UV-A light illumination, formation of iodine from iodide ion on the surfaces of anatase TiO(2), ZnO, Fe(2)O(3), CeO(2), MoO(3), Bi(2)O(3), and Nb(2)O(5) increases with the concentration of iodide ion, airflow rate and light intensity and conform to the Langmuir-Hinshelwood kinetic model. Measurement of the particle size of the semiconductor oxides by light scattering method and deduction of the same from the determined specific surface area show that the oxide particles agglomerate in suspension. However, mixtures of any two listed particulate semiconductors do not show enhanced photocatalytic formation of iodine indicating absence of interparticle charge transfer. The results are rationalized. Copyright © 2012 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Lee, Jong Ho; Shin, Yong Cheol; Jin, Oh Seong; Kang, Seok Hee; Hwang, Yu-Shik; Park, Jong-Chul; Hong, Suck Won; Han, Dong-Wook
2015-07-01
Human mesenchymal stem cells (hMSCs) have great potential as cell sources for bone tissue engineering and regeneration, but the control and induction of their specific differentiation into bone cells remain challenging. Graphene-based nanomaterials are considered attractive candidates for biomedical applications such as scaffolds in tissue engineering, substrates for SC differentiation and components of implantable devices, due to their biocompatible and bioactive properties. Despite the potential biomedical applications of graphene and its derivatives, only limited information is available regarding their osteogenic activity. This study concentrates upon the effects of reduced graphene oxide (rGO)-coated hydroxyapatite (HAp) composites on osteogenic differentiation of hMSCs. The average particle sizes of HAp and rGO were 1270 +/- 476 nm and 438 +/- 180 nm, respectively. When coated on HAp particulates, rGO synergistically enhanced spontaneous osteogenic differentiation of hMSCs, without hampering their proliferation. This result was confirmed by determining alkaline phosphatase activity and mineralization of calcium and phosphate as early and late stage markers of osteogenic differentiation. It is suggested that rGO-coated HAp composites can be effectively utilized as dental and orthopedic bone fillers since these graphene-based particulate materials have potent effects on stimulating the spontaneous differentiation of MSCs and show superior bioactivity and osteoinductive potential.Human mesenchymal stem cells (hMSCs) have great potential as cell sources for bone tissue engineering and regeneration, but the control and induction of their specific differentiation into bone cells remain challenging. Graphene-based nanomaterials are considered attractive candidates for biomedical applications such as scaffolds in tissue engineering, substrates for SC differentiation and components of implantable devices, due to their biocompatible and bioactive properties. Despite the potential biomedical applications of graphene and its derivatives, only limited information is available regarding their osteogenic activity. This study concentrates upon the effects of reduced graphene oxide (rGO)-coated hydroxyapatite (HAp) composites on osteogenic differentiation of hMSCs. The average particle sizes of HAp and rGO were 1270 +/- 476 nm and 438 +/- 180 nm, respectively. When coated on HAp particulates, rGO synergistically enhanced spontaneous osteogenic differentiation of hMSCs, without hampering their proliferation. This result was confirmed by determining alkaline phosphatase activity and mineralization of calcium and phosphate as early and late stage markers of osteogenic differentiation. It is suggested that rGO-coated HAp composites can be effectively utilized as dental and orthopedic bone fillers since these graphene-based particulate materials have potent effects on stimulating the spontaneous differentiation of MSCs and show superior bioactivity and osteoinductive potential. Electronic supplementary information (ESI) available: Additional figures. See DOI: 10.1039/c5nr01580d
Lewis, Joshua B; Bodine, Jared S; Gassman, Jason R; Muñoz, Samuel Arce; Milner, Dallin C; Dunaway, Todd M; Egbert, Kaleb M; Monson, Troy D; Broberg, Dallin S; Arroyo, Juan A; Reynolds, Paul R
2018-04-25
Claudin-6 (Cldn6) is a tetraspanin transmembrane protein that contributes to tight junctional complexes and has been implicated in the maintenance of lung epithelial barriers. In the present study, we tested the hypothesis that genetic up-regulation of Cldn-6 influences inflammation in mice exposed to short-term environmental diesel particulate matter (DPM). Mice were subjected to ten exposures of nebulized DPM (PM2.5) over a period of 20 days via a nose-only inhalation system (Scireq, Montreal, Canada). Using real-time RT-PCR, we discovered that the Cldn6 gene was up-regulated in control mice exposed to DPM and in lung-specific transgenic mice that up-regulate Cldn-6 (Cldn-6 TG). Interestingly, DPM did not further enhance Cldn-6 expression in Cldn-6 TG mice. DPM caused increased cell diapedesis into bronchoalveolar lavage fluid (BALF) from control mice; however, Cldn-6 TG mice had less total cells and PMNs in BALF following DPM exposure. Because Cldn-6 TG mice had diminished cell diapedesis, other inflammatory intermediates were screened to characterize the impact of increased Cldn-6 on inflammatory signaling. Cytokines that mediate inflammatory responses including TNF-α and IL-1β were differentially regulated in Cldn6 TG mice and controls following DPM exposure. These results demonstrate that epithelial barriers organized by Cldn-6 mediate, at least in part, diesel-induced inflammation. Further work may show that Cldn-6 is a key target in understanding pulmonary epithelial gateways exacerbated by environmental pollution.
Receptor model-based source apportionment of particulate pollution in Hyderabad, India.
Guttikunda, Sarath K; Kopakka, Ramani V; Dasari, Prasad; Gertler, Alan W
2013-07-01
Air quality in Hyderabad, India, often exceeds the national ambient air quality standards, especially for particulate matter (PM), which, in 2010, averaged 82.2 ± 24.6, 96.2 ± 12.1, and 64.3 ± 21.2 μg/m(3) of PM10, at commercial, industrial, and residential monitoring stations, respectively, exceeding the national ambient standard of 60 μg/m(3). In 2005, following an ordinance passed by the Supreme Court of India, a source apportionment study was conducted to quantify source contributions to PM pollution in Hyderabad, using the chemical mass balance (version 8.2) receptor model for 180 ambient samples collected at three stations for PM10 and PM2.5 size fractions for three seasons. The receptor modeling results indicated that the PM10 pollution is dominated by the direct vehicular exhaust and road dust (more than 60%). PM2.5 with higher propensity to enter the human respiratory tracks, has mixed sources of vehicle exhaust, industrial coal combustion, garbage burning, and secondary PM. In order to improve the air quality in the city, these findings demonstrate the need to control emissions from all known sources and particularly focus on the low-hanging fruits like road dust and waste burning, while the technological and institutional advancements in the transport and industrial sectors are bound to enhance efficiencies. Andhra Pradesh Pollution Control Board utilized these results to prepare an air pollution control action plan for the city.
Davourie, Julia; Westfall, Luke; Ali, Mohammed; McGough, Doreen
2017-01-01
Life-cycle assessments (LCAs) provide a wealth of industry data to assist in evaluating the environmental impacts of industrial processes and product supply chains. In this investigation, data from a recent LCA covering global manganese alloy production was used to evaluate sources of particulate matter (PM) emissions associated with the manganese alloy supply chain. The analysis is aimed at providing an empirical, industry-averaged breakdown of the contribution that processes and emissions controls have on total emissions, manganese releases and occupational exposure. The assessment shows that 66% of PM emissions associated with manganese production occur beyond manganese facilities. Direct or on-site emissions represent 34% of total PM and occur predominantly as disperse sources during mineral extraction and hauling, and as primary furnace emissions. The largest contribution of manganese-bearing PM at ground-level is associated with fugitive emissions from metal and slag tapping, casting, crushing and screening. The evaluation provides a high-level ranking of emissions by process area, to assist in identifying priority areas for industry-wide initiatives to reduce emissions and occupational exposure of manganese. The range of PM emission levels in industry indicate that further enhancements in PM emissions can be achieved by sharing of best practices in emissions controls, limiting furnace conditions which lead to by-passing of emissions controls and application of secondary emission controls to capture fugitive emissions during tapping and casting. The LCA approach to evaluating PM emissions underscores the important role that process optimization and resource efficiency have on reducing PM emissions throughout the manganese supply chain. Copyright © 2016. Published by Elsevier B.V.
EVALUATION OF FOUR NOVEL FINE PARTICULATE COLLECTION DEVICES
The report gives results of an experimental performance evaluation of four novel fine particulate control devices: the Johns-Manville Cleanable High-Efficiency Air Filtration (CHEAF) System, the APS Electrostatic Scrubber, the APS Electrotube, and the TRW Charged Droplet Scrubber...
HIGH-TEMPERATURE AND HIGH-PRESSURE PARTICULATE CONTROL REQUIREMENTS
The report reviews and evaluates high-temperature and high-pressure particulate cleanup requirements of existing and proposed energy processes. The study's aims are to define specific high-temperature and high-pressure particle removal problems, to indicate potential solutions, a...
Setting and Reviewing Standards to Control Particulate Matter (PM) Pollution
The Clean Air Act requires EPA to set national air quality standards for particulate matter, and to periodically review the standards to ensure that they provide adequate health and environmental protection, updating those standards as necessary.
Innovative formulation of nystatin particulate systems in toothpaste for candidiasis treatment.
Pinto Reis, Catarina; Vasques Roque, Luís; Baptista, Marina; Rijo, Patrícia
2016-01-01
Oral candidiasis is a mycosis on the mucous membranes of the mouth but not limited to the mouth. Nystatin is one of the most frequently employed antifungal agents to treat infections and may be safely given orally as well as applied topically but its absorption through mucocutaneous membranes such as the gut and the skin is minimal. The purpose of this study is to enhance the effectiveness of nystatin using particulate system such as beads, micro- and nanoparticles of alginate incorporated into toothpaste. Those particulate systems of nystatin were prepared by extrusion/external gelation for beads and emulsification/internal gelation for micro- and nanoparticles and characterized. Small, anionic charged and monodispersed particles were successfully produced. The type of particulate system influenced all previous parameters, being microparticles the most suitable particulate system of nystatin showing the slowest release, the highest inhibitory effect of Candida albicans over a period of one year. Those results allowed the conclusion that alginate exhibits properties that enable the in vitro functionality of encapsulated nystatin and thus may provide the basis for new successful approaches for the treatment of oral antifungal infections such as oral candidiasis.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 7 2012-07-01 2012-07-01 false How do I monitor the temperature of... I monitor the temperature of flue gases at the inlet of my particulate matter control device? You must install, calibrate, maintain, and operate a device to continuously measure the temperature of the...
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 7 2013-07-01 2013-07-01 false How do I monitor the temperature of... I monitor the temperature of flue gases at the inlet of my particulate matter control device? You must install, calibrate, maintain, and operate a device to continuously measure the temperature of the...
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 7 2014-07-01 2014-07-01 false How do I monitor the temperature of... I monitor the temperature of flue gases at the inlet of my particulate matter control device? You must install, calibrate, maintain, and operate a device to continuously measure the temperature of the...
Atmospheric Science Data Center
2014-05-15
... Radiance Ellipsoid Product. MISR uses this enhanced sensitivity along with the angular variation in signal to monitor particulate ... of MISR's unique capability of providing moderately high spatial resolution, calibrated imagery at very oblique angles. Gradations ...
Low exhaust temperature electrically heated particulate matter filter system
Gonze, Eugene V [Pinckney, MI; Paratore, Jr., Michael J.; Bhatia, Garima [Bangalore, IN
2012-02-14
A system includes a particulate matter (PM) filter, a sensor, a heating element, and a control module. The PM filter includes with an upstream end that receives exhaust gas, a downstream end and multiple zones. The sensor detects a temperature of the exhaust gas. The control module controls current to the heating element to convection heat one of the zones and initiate a regeneration process. The control module selectively increases current to the heating element relative to a reference regeneration current level when the temperature is less than a predetermined temperature.
Enhanced phenol-photodegradation by particulate semiconductor mixtures: interparticle electron-jump.
Karunakaran, C; Dhanalakshmi, R; Gomathisankar, P; Manikandan, G
2010-04-15
Degradation of phenol on suspended TiO(2), ZnO, CdO, Fe(2)O(3), CuO, ZnS and Nb(2)O(5) particles under UV-A light exhibit identical photokinetic behavior; follow first-order kinetics, display linear dependence on the photon flux and slowdown with increase of pH. All the semiconductors show sustainable photocatalytic activity. Dissolved O(2) is essential for the photodegradation and oxidizing agents like H(2)O(2), Na(2)BO(3), K(2)S(2)O(8), KBrO(3), KIO(3) and KIO(4), reducing agents such as NaNO(2) and Na(2)SO(3) and sacrificial electron donors like hydroquinone, diphenyl amine and trimethyl amine enhance the degradation. However, the photocatalysis is insensitive to pre-sonication. Two particulate semiconductors present together, under suspension and at continuous motion, enhance the photocatalytic degradation up to about four-fold revealing interparticle electron-jump. 2009 Elsevier B.V. All rights reserved.
Method for improved gas-solids separation
Kusik, C.L.; He, B.X.
1990-11-13
Methods are disclosed for the removal of particulate solids from a gas stream at high separation efficiency, including the removal of submicron size particles. The apparatus includes a cyclone separator type of device which contains an axially mounted perforated cylindrical hollow rotor. The rotor is rotated at high velocity in the same direction as the flow of an input particle-laden gas stream to thereby cause enhanced separation of particulate matter from the gas stream in the cylindrical annular space between the rotor and the sidewall of the cyclone vessel. Substantially particle-free gas passes through the perforated surface of the spinning rotor and into the hollow rotor, from where it is discharged out of the top of the apparatus. Separated particulates are removed from the bottom of the vessel. 4 figs.
Method for improved gas-solids separation
Kusik, Charles L.; He, Bo X.
1990-01-01
Methods are disclosed for the removal of particulate solids from a gas stream at high separation efficiency, including the removal of submicron size particles. The apparatus includes a cyclone separator type of device which contains an axially mounted perforated cylindrical hollow rotor. The rotor is rotated at high velocity in the same direction as the flow of an input particle-laden gas stream to thereby cause enhanced separation of particulate matter from the gas stream in the cylindrical annular space between the rotor and the sidewall of the cyclone vessel. Substantially particle-free gas passes through the perforated surface of the spinning rotor and into the hollow rotor, from when it is discharged out of the top of the apparatus. Separated particulates are removed from the bottom of the vessel.
Bioengineering towards self-assembly of particulate vaccines.
Rehm, Bernd H A
2017-12-01
There is an unmet demand for safe and efficient vaccines for prevention of various infectious diseases. Subunit vaccines comprise selected pathogen specific antigens are a safe alternative to whole organism vaccines. However they often lack immunogenicity. Natural and synthetic self-assembling polymers and proteins will be reviewed in view their use to encapsulate and/or display antigens to serve as immunogenic antigen carriers for induction of protective immunity. Recent advances made in in vivo assembly of antigen-displaying polyester inclusions will be a focus. Particulate vaccines are inherently immunogenic due to enhanced uptake by antigen presenting cells which process antigens mediating adaptive immune responses. Bioengineering approaches enable the design of tailor-made particulate vaccines to fine tune immune responses towards protective immunity. Copyright © 2017 Elsevier Ltd. All rights reserved.
Jhun, Iny; Gaffin, Jonathan M; Coull, Brent A; Huffaker, Michelle F; Petty, Carter R; Sheehan, William J; Baxi, Sachin N; Lai, Peggy S; Kang, Choong-Min; Wolfson, Jack M; Gold, Diane R; Koutrakis, Petros; Phipatanakul, Wanda
Home-based interventions to improve indoor air quality have demonstrated benefits for asthma morbidity, yet little is known about the effect of environmental interventions in the school setting. We piloted the feasibility and effectiveness of a classroom-based air cleaner intervention to reduce particulate pollutants in classrooms of children with asthma. In this pilot randomized controlled trial, we assessed the effect of air cleaners on indoor air particulate pollutant concentrations in 18 classrooms (9 control, 9 intervention) in 3 urban elementary schools. We enrolled 25 children with asthma (13 control, 12 intervention) aged 6 to 10 years. Classroom air pollutant measurements and spirometry were completed once before and twice after randomization. Asthma symptoms were surveyed every 3 months. Baseline classroom levels of fine particulate matter (particulate matter with diameter of <2.5 μm [PM 2.5 ]) and black carbon (BC) were 6.3 and 0.41 μg/m 3 , respectively. When comparing the intervention to the control group, classroom PM 2.5 levels were reduced by 49% and 42% and BC levels were reduced by 58% and 55% in the first and second follow-up periods, respectively (P < .05 for all comparisons). When comparing the children randomized to intervention and control classrooms, there was a modest improvement in peak flow, but no significant changes in forced expiratory volume in 1 second (FEV 1 ) and asthma symptoms. In this pilot study, a classroom-based air cleaner intervention led to significant reductions in PM 2.5 and BC. Future large-scale studies should comprehensively evaluate the effect of school-based environmental interventions on pediatric asthma morbidity. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.
Particle or particulate matter is defined as any finely divided solid or liquid material, other than uncombined water, emitted to the ambient air as measured by applicable reference methods, or an equivalent or alternative method, or by a test method specified in 40CFR50.
Plasma regenerated particulate trap and NO.sub.x reduction system
Penetrante, Bernardino M.; Vogtlin, George E.; Merritt, Bernard T.; Brusasco, Raymond M.
2000-01-01
A non-catalytic two-stage process for removal of NO.sub.x and particulates from engine exhaust comprises a first stage that plasma converts NO to NO.sub.2 in the presence of O.sub.2 and hydrocarbons, and a second stage, which preferably occurs simultaneously with the first stage, that converts NO.sub.2 and carbon soot particles to respective environmentally benign gases that include N.sub.2 and CO.sub.2. By preconverting NO to NO.sub.2 in the first stage, the efficiency of the second stage for NO.sub.x reduction is enhanced while carbon soot from trapped particulates is simultaneously converted to CO.sub.2 when reacting with the NO.sub.2 (that converts to N.sub.2). For example, an internal combustion engine exhaust is connected by a pipe to a chamber where carbon-containing particulates are electrostatically trapped or filtered and a non-thermal plasma converts NO to NO.sub.2 in the presence of O.sub.2 and hydrocarbons. Volatile hydrocarbons (C.sub.x H.sub.y) from the trapped particulates are oxidized in the plasma and the remaining soot from the particulates reacts with the NO.sub.2 to convert NO.sub.2 to N.sub.2, and the soot to CO.sub.2. The nitrogen exhaust components remain in the gas phase throughout the process, with no accompanying adsorption.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Haas, J.C.; Olivo, C.A.; Wilson, K.B.
1994-04-01
An experimental test plan has been prepared for DOE/METC review and approval to develop a filter media suitable for multi-contaminant control in granular-bed filter (GBF) applications. The plan includes identification, development, and demonstration of methods for enhanced media morphology, chemical reactivity, and mechanical strength. The test plan includes media preparation methods, physical and chemical characterization methods for fresh and reacted media, media evaluation criteria, details of test and analytical equipment, and test matrix of the proposed media testing. A filter media composed of agglomerated limestone and clay was determined to be the best candidate for multi-contaminate control in GBF operation.more » The combined limestone/clay agglomerate has the potential to remove sulfur and alkali species, in addition to particulate, and possibly halogens and trace heavy metals from coal process streams.« less
Clean room survey and assessment, volume 5, appendix H
NASA Technical Reports Server (NTRS)
1991-01-01
The scope of this task is to perform a comparative analysis of the various Environmental Control Life Support System (ECLSS) options for different growth scenarios. The Space Station Freedom ECLSS design and existing ground-based clean room facilities are used as a baseline for comparison. Specifically addressed here are the ground based clean room facilities at the Marshall Space Flight Center (MSFC). Given here is an evaluation of the facilities, equipment, technologies, and procedures used to maintain specified environments in typical aerospace industrial areas. Twenty-five specific clean rooms are evaluated. The objectives were to collect, compare, and catalog data for each specified facility in the areas of engineering and design, construction materials, work stations, contamination control, particulate elimination, entry systems, and instrumentation, and to make recommendations concerning enhancements required to assure an efficient and orderly evolution of MSFC clean room environmental control facilities.
Sedimentary particulate iron: the missing micronutrients ?
NASA Astrophysics Data System (ADS)
Beghoura, Houda; Gorgues, Thomas; Aumont, Olivier; Planquette, Hélène
2017-04-01
Iron is known to regulate the marine primary production and to impact the structure of ecosystems. Indeed, iron is the limiting nutrient for the phytoplankton growth over about 30% of the global ocean. However, the nature of the external sources of iron to the ocean and their quantification remain uncertain. Among these external sources, the sediment sources have been recently shown to be underestimated. Besides, since the operationally defined dissolved iron (which is the sum of truly dissolved and colloidal iron) was traditionally assumed to be the only form available to phytoplankton and bacteria, most studies have focused on the supply of dissolved iron to the ocean, the role of the particulate fraction of iron being largely ignored. This traditional view has been recently challenged, noticeably, by observational evidences. Indeed, in situ observations have shown that large amounts of particulate iron are being resuspended from continental margins to the open ocean thanks to fine grained particles' transport over long distances. A fraction of this particulate iron may dissolve and thereby fuel the phytoplankton growth. The magnitude of the sedimentary sources of particulate iron and the releasing processes affecting this iron phase are not yet well constrained or quantified. As a consequence, the role of sedimentary particulate iron in the biogeochemical cycles is still unclear despite its potentially major widespread importance. Here, we propose a modeling exercise to assess the first order impacts of this newly considered particulate sedimentary iron on global ocean biogeochemistry. We designed global experiments with a coupled dynamical-biogeochemical model (NEMO-PISCES). First, a control simulation that includes only a sediment source of iron in the dissolved phase has been run. Then, this control simulation is being compared with simulations, in which we include a sediment source of iron in both phases (dissolved as well as particulate). Those latter simulations have been performed using a range of particulate iron dissolution rates (from published studies and laboratory experiment results) that will permit to test the sensitivity of the biogeochemical response.
Terada, N; Maesako, K; Hiruma, K; Hamano, N; Houki, G; Konno, A; Ikeda, T; Sai, M
1997-10-01
Diesel exhaust particulates (DEP) are a common air pollutant from diesel-engine-powered car exhaust and are thought to cause chronic airway diseases. On the other hand, eosinophils are major components of allergic inflammatory disorders such as asthma, nasal allergy and atopic dermatitis. We examined the effects of DEP and DEP extract (extract of polyaromatic hydrocarbons) on eosinophil adhesion, survival rate and degranulation. Eosinophils, human mucosal microvascular endothelial cells (HMMECs) and human nasal epithelial cells (HNECs) were preincubated in the presence or absence of DEP and DEP extract. 35S-labeled eosinophils were allowed to adhere to monolayers of HMMECs and HNECs. After washing, 35S radioactivity was determined and numbers of adherent eosinophils were calculated using each standard curve. The effects of DEP and DEP extract on eosinophil survival rate and degranulation were also determined. Although neither DEP nor DEP extract affected the adhesiveness of HMMECs and HNECs to eosinophils, 5 ng/ml of DEP extract and 50 ng/ml of DEP extract each significancy increased eosinophil adhesiveness to HNECs (134+/-9 and 143+/-8%, respectively; p<0.01 vs. control), but neither effected eosinophil adhesiveness to HMMECs. DEP extract also induced eosinophil degranulation without changing the eosinophil survival rate. Given that eosinophil-derived lipid mediators and toxic proteins play important roles in the development of nasal allergy, the above findings strongly suggest that DEP plays an important role in promoting the nasal hypersensitivity induced by enhanced eosinophil infiltration of epithelium and eosinophil degranulation.
Siddiqui, Komal; Waris, Abdul; Akber, Habiba; Munir, Kinza; Mir, Maria; Khan, Muhammad Waseem; Aman, Waqar; Fakhar-Ud-Din
2017-01-01
Bioavailability is the segment of dose that is bioavailable for its therapeutic effect on the systemic circulation without any change in its characteristics, after administration by either route. It is one of the fundamental pharmacokinetic properties of drugs. It is important because, it defines the amount of drug to be administered for its intended therapeutic effect. If drug is more bioavailable, less amount of it is required to obtain therapeutic effect. However, it is also worth mentioning that most of the newly discovered therapeutic agents have poor solubility and thus low bioavailability. In this article, various methods including conventional and advanced, have been reviewed that could be potentially used for the enhancement of bioavailability. Moreover, the benefits and drawbacks of all the strategies are deliberated to comprehend the probable use of each method supported by latest references. Various strategies have been developed to enhance the solubility and thus bioavailability of numerous drugs, some of which are discussed here. All these strategies involve different approaches to improve the bioavailability including physical adaptation, chemical modification and controlling particle size of the engineered particle. These strategies, particularly the nano-particulate systems, not only improve the bioavailability of drugs but at the same time diminish the possible toxicities of the incorporated drugs. It can be concluded that this would be a new source of information for the readers. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
Glacial Cycles Influence Marine Methane Hydrate Formation
NASA Astrophysics Data System (ADS)
Malinverno, A.; Cook, A. E.; Daigle, H.; Oryan, B.
2018-01-01
Methane hydrates in fine-grained continental slope sediments often occupy isolated depth intervals surrounded by hydrate-free sediments. As they are not connected to deep gas sources, these hydrate deposits have been interpreted as sourced by in situ microbial methane. We investigate here the hypothesis that these isolated hydrate accumulations form preferentially in sediments deposited during Pleistocene glacial lowstands that contain relatively large amounts of labile particulate organic carbon, leading to enhanced microbial methanogenesis. To test this hypothesis, we apply an advection-diffusion-reaction model with a time-dependent organic carbon deposition controlled by glacioeustatic sea level variations. In the model, hydrate forms in sediments with greater organic carbon content deposited during the penultimate glacial cycle ( 120-240 ka). The model predictions match hydrate-bearing intervals detected in three sites drilled on the northern Gulf of Mexico continental slope, supporting the hypothesis of hydrate formation driven by enhanced organic carbon burial during glacial lowstands.
INVESTIGATING THE PREFERENTIAL DISSOLUTION OF LEAD FROM SOLDER PARTICULATES
During a building corrosion control study, bottles containing acid-preserved water samples with high levels of lead often had particulate material on the bottom. Scanning electron microscope analysis of the particles showed the presence of tin and the absence of lead, indicating ...
Bayesian Hierarchical Modeling of Cardiac Response to Particulate Matter Exposure
Studies have linked increased levels of particulate air pollution to decreased autonomic control, as measured by heart rate variability (HRV), particularly in populations such as the elderly. In this study, we use data obtained from the 1998 USEPA epidemiology-exposure longitudin...
Particulate and Gaseous Emissions Measurement System (PAGEMS) Project
NASA Technical Reports Server (NTRS)
Kostic, Milivoje
2003-01-01
Professor Kostic will work on the current UEET program of the Aerosol and Particulate task. This task will focus on: how to acquire experimental data through Labview software how to make the data acquisition system more efficient trouble existing problem of the labview software recommend a better system improve existing system with better data and usually friendly.Three different assignments in this project included:Particle-Size Distribution Data Presentation;Error or Uncertainty Analysis of Measurement Results; and Enhancement of LabVlRN Data Acquisition Program for GRC PAGEMS Project.
NASA Astrophysics Data System (ADS)
Bharathkumar, S.; Sakar, M.; Balakumar, S.
2018-04-01
We made an attempt to construct a photocatalytic and biosensor platform by using bismuth ferrite (BiFeO3/BFO) particulates and fibers nanostructures towards the degradation of dye and electrochemical sensing of ascorbic acid. The crystal phase and morphology of the BFO nanostructures were confirmed using XRD and FESEM respectively. Further, their photocatalytic activity was tested under sunlight. The BFO fibers showed relatively an enhanced degradation property and an efficient electrochemical sensing property compared to the Particulates.
Chen, Shangwu; Zhang, Qin; Nakamoto, Tomoko; Kawazoe, Naoki; Chen, Guoping
2016-03-01
Engineering of cartilage tissue in vitro using porous scaffolds and chondrocytes provides a promising approach for cartilage repair. However, nonuniform cell distribution and heterogeneous tissue formation together with weak mechanical property of in vitro engineered cartilage limit their clinical application. In this study, gelatin porous scaffolds with homogeneous and open pores were prepared using ice particulates and freeze-drying. The scaffolds were used to culture bovine articular chondrocytes to engineer cartilage tissue in vitro. The pore structure and mechanical property of gelatin scaffolds could be well controlled by using different ratios of ice particulates to gelatin solution and different concentrations of gelatin. Gelatin scaffolds prepared from ≥70% ice particulates enabled homogeneous seeding of bovine articular chondrocytes throughout the scaffolds and formation of homogeneous cartilage extracellular matrix. While soft scaffolds underwent cellular contraction, stiff scaffolds resisted cellular contraction and had significantly higher cell proliferation and synthesis of sulfated glycosaminoglycan. Compared with the gelatin scaffolds prepared without ice particulates, the gelatin scaffolds prepared with ice particulates facilitated formation of homogeneous cartilage tissue with significantly higher compressive modulus. The gelatin scaffolds with highly open pore structure and good mechanical property can be used to improve in vitro tissue-engineered cartilage.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zaveri, R.A.; Kleinman, L.; Berkowitz, C. M.
2010-06-01
Nighttime chemical evolution of aerosol and trace gases in a coal-fired power plant plume was monitored with the Department of Energy Grumman Gulfstream-1 aircraft during the 2002 New England Air Quality Study field campaign. Quasi-Lagrangian sampling in the plume at increasing downwind distances and processing times was guided by a constant-volume balloon that was released near the power plant at sunset. While no evidence of fly ash particles was found, concentrations of particulate organics, sulfate, and nitrate were higher in the plume than in the background air. The enhanced sulfate concentrations were attributed to direct emissions of gaseous H{sub 2}SO{submore » 4}, some of which had formed new particles as evidenced by enhanced concentrations of nucleation-mode particles in the plume. The aerosol species were internally mixed and the particles were acidic, suggesting that particulate nitrate was in the form of organic nitrate. The enhanced particulate organic and nitrate masses in the plume were inferred as secondary organic aerosol, which was possibly formed from NO{sub 3} radical-initiated oxidation of isoprene and other trace organic gases in the presence of acidic sulfate particles. Microspectroscopic analysis of particle samples suggested that some sulfate was in the form of organosulfates. Microspectroscopy also revealed the presence of sp{sup 2} hybridized C = C bonds, which decreased with increasing processing time in the plume, possibly because of heterogeneous chemistry on particulate organics. Constrained plume modeling analysis of the aircraft and tetroon observations showed that heterogeneous hydrolysis of N{sub 2}O{sub 5} was negligibly slow. These results have significant implications for several issues related to the impacts of power plant emissions on air quality and climate.« less
Gradoville, Mary R.; White, Angelicque E.; Letelier, Ricardo M.
2014-01-01
We investigated the effects of elevated pCO2 on cultures of the unicellular N2-fixing cyanobacterium Crocosphaera watsonii WH8501. Using CO2-enriched air, cultures grown in batch mode under high light intensity were exposed to initial conditions approximating current atmospheric CO2 concentrations (∼400 ppm) as well as CO2 levels corresponding to low- and high-end predictions for the year 2100 (∼750 and 1000 ppm). Following acclimation to CO2 levels, the concentrations of particulate carbon (PC), particulate nitrogen (PN), and cells were measured over the diurnal cycle for a six-day period spanning exponential and early stationary growth phases. High rates of photosynthesis and respiration resulted in biologically induced pCO2 fluctuations in all treatments. Despite this observed pCO2 variability, and consistent with previous experiments conducted under stable pCO2 conditions, we observed that elevated mean pCO2 enhanced rates of PC production, PN production, and growth. During exponential growth phase, rates of PC and PN production increased by ∼1.2- and ∼1.5-fold in the mid- and high-CO2 treatments, respectively, when compared to the low-CO2 treatment. Elevated pCO2 also enhanced PC and PN production rates during early stationary growth phase. In all treatments, PC and PN cellular content displayed a strong diurnal rhythm, with particulate C:N molar ratios reaching a high of 22∶1 in the light and a low of 5.5∶1 in the dark. The pCO2 enhancement of metabolic rates persisted despite pCO2 variability, suggesting a consistent positive response of Crocosphaera to elevated and fluctuating pCO2 conditions. PMID:25343645
Federal Register 2010, 2011, 2012, 2013, 2014
2013-04-03
... Environmental protection, Air pollution control, Incorporation by reference, Nitrogen dioxide, Particulate... Promulgation of Air Quality Implementation Plans; Pennsylvania; Motor Vehicle Emissions Budgets for the Pennsylvania Counties in the Philadelphia-Wilmington, PA-NJ-DE 1997 Fine Particulate Matter Nonattainment Area...
Particulates and fine dust removal: processes and equipment
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sittig, M.
1977-01-01
Particulates and fine dust created by man's activities contribute significantly to all major aspects of air pollution. While the generation of natural fine dusts is also very large in some parts of the earth, industrially generated, particle-loaded air emissions may push the particulate level to a point where acceptable air quality standards are exceeded continuously. How to reduce such emissions at the source, and what processes and equipment to use, is the subject of this book, which is based on reports of federally-financed air pollution studies as well as U.S. patents. Following an introduction with an overview of industrial particulatemore » emissions, emission data and emission control processes are discussed for the following specific industries: airlines; asphalt; cement; coal; electric utilities; ferrous metals; fertilizer; food; forest products; paper; chemicals; nonferrous metals; nuclear; petroleum refining; stone and clay; and textiles. Conventional and innovative particle removal devices are described. The disposal of collected particles is discussed. The economic and energy consumption aspects of particulate control are presented. (LCL)« less
Fogging formulations for fixation of particulate contamination in ductwork and enclosures
Maresca, Jr., Joseph W.; Kostelnik, Lori M.; Kriskivich, James R.; Demmer, Rick L.; Tripp, Julia L.
2015-09-08
A method and an apparatus using aqueous fixatives for fogging of ventilation ductwork, enclosures, or buildings containing dust, lint, and particulates that may be contaminated by radionuclides and other dangerous or unsafe particulate contaminants, which method and apparatus are capable of (1) obtaining full coverage within the ductwork and (2) penetrating and fixing the lint, dust and large particles present in the ductwork so that no airborne particles are released during or after the application of the fixative. New aqueous fogging solutions outperform conventional glycerin-based solutions. These aqueous solutions will fog using conventional methods of application and contain a surfactant to aid wetting and penetration of the lint and dust, a binder to stabilize loose or respirable particles, and an agent to aid in fogging and enhance adhesiveness. The solutions are safe and easy to use.
Improving properties of Mg with Al–Cu additions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rashad, Muhammad, E-mail: rashadphy87@gmail.com; National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044; Pan, Fusheng, E-mail: fspan@cqu.edu.cn
The present work reports improvement in tensile properties of the Mg matrix reinforced with micron-sized copper–aluminum particulate hybrids. The Al–Cu particulate hybrids were incorporated into the Mg matrix through powder metallurgy method. The synthesized alloys exhibited homogeneously dispersed Mg{sub 2}Cu particles in the matrix, therefore leading to a 110% increase in yield strength (221 MPa) and a 72% enhancement in ultimate tensile strength (284 MPa) by addition of 1.0 wt.%Al–0.6 wt.%Cu particle hybrids. Optical microscopy, scanning election microscopy, transmission electron microscopy and X-ray diffraction were used to investigate the microstructure and intermetallic phases of the synthesized alloys. - Highlights: •more » Mg matrix is reinforced with Al–Cu particulate hybrids. • Powder metallurgic method is used to fabricate the alloys. • Tensile strength and ductility were increased simultaneously.« less
Electrically heated particulate filter with zoned exhaust flow control
Gonze, Eugene V [Pinckney, MI
2012-06-26
A system includes a particulate matter (PM) filter that includes X zones. An electrical heater includes Y heater segments that are associated with respective ones of the X zones. The electrical heater is arranged upstream from and proximate with the PM filter. A valve assembly includes Z sections that are associated with respective ones of the X zones. A control module adjusts flow through each of the Z sections during regeneration of the PM filter via control of the valve assembly. X, Y and Z are integers.
Anderson, G. Brooke; Krall, Jenna R.; Peng, Roger D.; Bell, Michelle L.
2012-01-01
Epidemiologic studies have linked tropospheric ozone pollution and human mortality. Although research has shown that this relation is not confounded by particulate matter when measured by mass, little scientific evidence exists on whether confounding exists by chemical components of the particle mixture. Using mortality and particulate matter with aerodynamic diameter ≤2.5 µm (PM2.5) component data from 57 US communities (2000–2005), the authors investigate whether the ozone-mortality relation is confounded by 7 components of PM2.5: sulfate, nitrate, silicon, elemental carbon, organic carbon matter, sodium ion, and ammonium. Together, these components constitute most PM2.5 mass in the United States. Estimates of the effect of ozone on mortality were almost identical before and after controlling for the 7 components of PM2.5 considered (mortality increase/10-ppb ozone increase, before and after controlling: ammonium, 0.34% vs. 0.35%; elemental carbon, 0.36% vs. 0.37%; nitrate, 0.27% vs. 0.26%; organic carbon matter, 0.34% vs. 0.31%; silicon, 0.36% vs. 0.37%; sodium ion, 0.21% vs. 0.18%; and sulfate, 0.35% vs. 0.38%). Additionally, correlations were weak between ozone and each particulate component across all communities. Previous research found that the ozone-mortality relation is not confounded by particulate matter measured by mass; this national study indicates that the relation is also robust to control for specific components of PM2.5. PMID:23043133
Adam, T W; Chirico, R; Clairotte, M; Elsasser, M; Manfredi, U; Martini, G; Sklorz, M; Streibel, T; Heringa, M F; Decarlo, P F; Baltensperger, U; De Santi, G; Krasenbrink, A; Zimmermann, R; Prevot, A S H; Astorga, C
2011-01-01
The European Commission recently established a novel test facility for heavy-duty vehicles to enhance more sustainable transport. The facility enables the study of energy efficiency of various fuels/scenarios as well as the chemical composition of evolved exhaust emissions. Sophisticated instrumentation for real-time analysis of the gas and particulate phases of exhaust has been implemented. Thereby, gas-phase characterization was carried out by a Fourier transform infrared spectrometer (FT-IR; carbonyls, nitrogen-containing species, small hydrocarbons) and a resonance-enhanced multiphoton ionization time-of-flight mass spectrometer (REMPI-TOFMS; monocyclic and polycyclic aromatic hydrocarbons). For analysis of the particulate phase, a high-resolution time-of-flight aerosol mass spectrometer (HR-TOF-AMS; organic matter, chloride, nitrate), a condensation particle counter (CPC; particle number), and a multiangle absorption photometer (MAAP; black carbon) were applied. In this paper, the first application of the new facility in combination with the described instruments is presented, whereby a medium-size truck was investigated by applying different driving cycles. The goal was simultaneous chemical characterization of a great variety of gaseous compounds and particulate matter in exhaust on a real-time basis. The time-resolved data allowed new approaches to view the results; for example, emission factors were normalized to time-resolved consumption of fuel and were related to emission factors evolved during high speeds. Compounds could be identified that followed the fuel consumption, others showed very different behavior. In particular, engine cold start, engine ignition (unburned fuel), and high-speed events resulted in unique emission patterns.
NASA Astrophysics Data System (ADS)
Kristensen, Erik; Holmer, Marianne
2001-02-01
Carbon mineralization of fresh and aged diatoms ( Skeletonema costatum) and barley hay ( Hordeum vulgare) was followed for 23 to 35 d in sandy and silty sediment. By the use of a thin-layer flow-through technique, it was possible to expose the sediment selectively for oxygen, nitrate or sulfate as electron acceptors in the terminal oxidation of organic carbon. Decomposition took place in two basic stages. Mineralization of the rapidly leachable fraction of the fresh materials occurred rapidly and with the same constant rate regardless of the electron acceptor available, indicating that the dissolved organic carbon released initially was labile and readily available for all heterotrophic respirers. In the case of diatoms, decay of the remaining, more refractory, particulate fraction of fresh and aged diatoms were strikingly similar, although both were degraded 5 to 10 times faster under oxic than anoxic conditions. Most of the particulate remains of diatoms after leaching apparently belong to one fraction, which maintains the same degradability even after prolonged aging. With respect to hay, the late divergence in rates of aerobic and anaerobic decay (a factor of 4 to 5 for aged hay only after 20 d) indicated that the larger hay particles (<500 μm) became exhausted in labile organic matter much slower through time than fine-particulate diatoms (˜20 μm). Anaerobic carbon mineralization rates of diatoms and hay particulates with sulfate and nitrate as electron acceptors were similar or up to two times faster with sulfate. The generally low levels of dissolved organic carbon in all incubations after the initial leaching phase suggest that the limiting step of decomposition under both aerobic and anaerobic decay is the initial hydrolytic attack on the complex particulate remains. Based on a volumetric model, we show that the exposure of anoxic subsurface sediment containing partly degraded organic material to oxygen via irrigated worm burrows or by reworking may significantly enhance total sediment carbon oxidation. The enhancement in the irrigation case increases linearly with density (up to 80%) and is higher than the density-independent enhancement (10%) in the reworking case when abundance is above a lower limit of ˜400 individuals/m 2.
STATUS OF RESEARCH ON AIR QUALITY: MERCURY, TRACE ELEMENTS, AND PARTICULATE MATTER. (R827649)
The Air Quality Conference reviewed the state of science and policy on the pollutants mercury, trace elements, and particulate matter (PM) in the environment. Critical issues dealing with impacts on health and ecosystems, emission prevention and control, measurement methods, a...
SOURCE SAMPLING FINE PARTICULATE MATTER: WOOD-FIRED INDUSTRIAL BOILER
The report provides a profile for a wood-fired industrial boiler equipped with a multistage electrostatic precipitator control device. Along with the profile of emissions of fine particulate matter of aerodynamic diameter of 2.5 micrometers or less (PM-2.5), data are also provide...
HIGHLIGHTS FROM TECHNICAL MANUAL ON HOOD SYSTEM CAPTURE OF PROCESS FUGITIVE PARTICULATE EMISSIONS
The paper discusses a technical manual whose emphasis is on the design and evaluation of actual hood systems used to control various fugitive particulate emission sources. Engineering analyses of the most important hood types are presented to provide a conceptual understanding of...
Williamson, B J; Mikhailova, I; Purvis, O W; Udachin, V
2004-04-25
Scanning electron microscopy with energy-dispersive X-ray analysis (SEM-EDX) of particulate matter on lichen transplant thalli (Hypogymnia physodes) was assessed as a complementary technique to wet chemical analysis for source apportionment of airborne contaminants. Transplants (2 month exposure) stationed in the Cu smelter and former mining town of Karabash were compared with those from a control site 30 km south. Particulate matter in Karabash samples (715 analyses) showed higher levels of S, Pb, Cu, Sn and Zn compared with the control (598 analyses). Complex element associations among the particles confounded detailed mineralogical identifications, and therefore a simplified particle classification scheme was devised for source apportionment. Karabash samples contained high levels of particles classified as mining-related (MRP), and these were also identified in control samples, indicating wide spatial dispersion from the smelter and highlighting the sensitivity of the method. It was noted that MRP <2.5-microm diameter were poorly represented on lichen surfaces suggesting this may limit the usefulness of Hypogymnia transplants as proxies when assessing human health impacts from airborne particulates. Analyses of the lichen thallus surface (away from surface particulates) revealed high levels of Cu, Zn, Fe and Pb associated with organics in the Karabash samples compared with the control, with a proportionate loss of K, interpreted as being due to a stress-related increase in cell membrane permeability. This type of analysis may provide a novel SEM-EDX-based method for assessing lichen vitality. The techniques developed are presented and further implications of the study are discussed.
Lam, K S; Chan, F S; Fung, W Y; Lui, B S S; Lau, L W L
2006-04-01
A study was carried out to investigate the feasibility of achieving ultra low respirable suspended particulates (RSP) in commercial offices without major modification of existing ventilation systems by enhancing the particulates removal efficiency of existing central ventilation systems. Four types of filters which include pre-filters, cartridge filters, bag filters and high efficiency particulates air (HEPA) filters were tested in a commercial building in Causeway Bay. The results show that an RSP objective of <20 microg/m3 could be met by removing RSP from both the return air and outdoor air supply simultaneously. This level of performance is classed as 'excellent' by the Hong Kong Government, Environmental Protection Department. Filters with efficiency that exceed 80% placed both in the return air and outdoor air were sufficient to meet the objective. It is not necessary to install HEPA filters to achieve the 'excellent' class. The outdoor air filter has great influence on the steady state indoor RSP concentration while the effective cleaning rate is governed by the return air filter. Higher efficiency filters increased the static drop but the volume flow of the air fan was not affected significantly. The additional cost incurred was <5% of the existing operation cost. This paper reports a field study of RSP control for an indoor office environment. The results are directly applicable to building service engineering in the design of ventilation systems using air-handling units. Field observations indicated that indoor RSP in an office environment could be suppressed below 20 microg/m3 within 1 h by the simultaneous filtration of outdoor air and return air. Outdoor air filtration has a great influence on the steady state indoor concentration and return air filtration governs the cleaning rate. It is believed that the results of this study could be extended to the cleaning of other indoor pollutants such as volatile organic compounds.
Park, Duckshin; Lee, Taejeong; Lee, Yongil; Jeong, Wonseog; Kwon, Soon-Bark; Kim, Dongsool; Lee, Kiyoung
2017-01-01
Emission reduction is one of the most efficient control measures in fuel-powered locomotives. The purpose of this study was to determine the reduction in particulate matter (PM) and black carbon (BC) emissions following the installation of a fuel activation device (FAD). The FAD was developed to enhance fuel combustion by atomizing fuel and to increase the surface area per unit volume of injected fuel. Emission reduction by the FAD was evaluated by installing a FAD in an operating diesel locomotive in Mongolia. The test was conducted on a train operating on a round-trip 238-km route between Ulaanbaatar and Choir stations in Mongolia. The fuel consumption rate was slightly reduced following the FAD installation. The FAD installation decreased PM and BC emissions in the diesel locomotive, especially coarse PM. The PM 10 reductions achieved after FAD installation were 58.0, 69.7, and 34.2% for the constant velocity, stopping, and acceleration stages of the train's operation, respectively. The BC reduction rates were 29.5, 52.8, and 27.4% for the constant velocity, stopping, and acceleration stages, respectively. Copyright © 2016 Elsevier B.V. All rights reserved.
Huang, Qiting; Garoushi, Sufyan; Lin, Zhengmei; He, Jingwei; Qin, Wei; Liu, Fang; Vallittu, Pekka Kalevi; Lassila, Lippo Veli Juhana
2017-10-01
To investigate the reinforcing efficiency and light curing properties of discontinuous S2-glass fiber-particulate reinforced resin composite and to examine length distribution of discontinuous S2-glass fibers after a mixing process into resin composite. Experimental S2-glass fiber-particulate reinforced resin composites were prepared by mixing 10wt% of discontinuous S2-glass fibers, which had been manually cut into two different lengths (1.5 and 3.0mm), with various weight ratios of dimethacrylate based resin matrix and silaned BaAlSiO 2 filler particulates. The resin composite made with 25wt% of UDMA/SR833s resin system and 75wt% of silaned BaAlSiO 2 filler particulates was used as control composite which had similar composition as the commonly used resin composites. Flexural strength (FS), flexural modulus (FM) and work of fracture (WOF) were measured. Fractured specimens were observed by scanning electron microscopy. Double bond conversion (DC) and fiber length distribution were also studied. Reinforcement of resin composites with discontinuous S2-glass fibers can significantly increase the FS, FM and WOF of resin composites over the control. The fibers from the mixed resin composites showed great variation in final fiber length. The mean aspect ratio of experimental composites containing 62.5wt% of particulate fillers and 10wt% of 1.5 or 3.0mm cutting S2-glass fibers was 70 and 132, respectively. No difference was found in DC between resin composites containing S2-glass fibers with two different cutting lengths. Discontinuous S2-glass fibers can effectively reinforce the particulate-filled resin composite and thus may be potential to manufacture resin composites for high-stress bearing application. Copyright © 2017. Published by Elsevier Ltd.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-03-29
... holidays. We recommend that you telephone Matt Rau, Environmental Engineer, at (312) 886-6524 before visiting the Region 5 office. FOR FURTHER INFORMATION CONTACT: Matt Rau, Environmental Engineer, Control..., Restrictions on Particulate Emissions from Industrial Sources, on December 13, 2011. The revised rule was...
USDA-ARS?s Scientific Manuscript database
The study of health impacts, emission estimation of particulate matter (PM), and development of new control technologies require knowledge of PM characteristics. Among these PM characteristics, the particle size distribution (PSD) is perhaps the most important physical parameter governing particle b...
A LOW COST CATALYTIC FILTER FOR SIMULTANEOUS VOC AND PARTICULATE REMOVAL - PHASE II
Emissions of VOC's are subject to control by the EPA both because VOC's are regarded as ozone precursors and because many specific VOC's are hazardous air pollutants (HAP's) under the Clean Air Act Amendments. A number of industries generate offgases with both fine particul...
40 CFR 52.2276 - Control strategy and regulations: Particulate matter.
Code of Federal Regulations, 2010 CFR
2010-07-01
... its limestone quarry facilities near New Braunfels, Comal County, Texas shall install fabric filters... of the fabric filters, Parker Brothers and Co., Inc., shall not emit particulate matter in excess of 0.03 grains per standard cubic foot from the exhaust stack of the fabric filter on its primary...
40 CFR 52.2276 - Control strategy and regulations: Particulate matter.
Code of Federal Regulations, 2013 CFR
2013-07-01
... its limestone quarry facilities near New Braunfels, Comal County, Texas shall install fabric filters... of the fabric filters, Parker Brothers and Co., Inc., shall not emit particulate matter in excess of 0.03 grains per standard cubic foot from the exhaust stack of the fabric filter on its primary...
Particulate measurement and control devices for hot mix asphalt plants.
DOT National Transportation Integrated Search
1973-01-01
The emission of particulates is the main form of air pollution from hot mix asphalt plants. The measurement of these emissions in the ambient air may be used by the state and the plant personnel to monitor the quality of air in the area of a plant. S...
40 CFR 52.2276 - Control strategy and regulations: Particulate matter.
Code of Federal Regulations, 2012 CFR
2012-07-01
... its limestone quarry facilities near New Braunfels, Comal County, Texas shall install fabric filters... of the fabric filters, Parker Brothers and Co., Inc., shall not emit particulate matter in excess of 0.03 grains per standard cubic foot from the exhaust stack of the fabric filter on its primary...
Background Particulate air pollution episodes have been associated with increased daily death. However, there is little direct evidence that diminished particulate air pollution concentrations would lead to reductions in death rates. We assessed the effect of ...
CHARACTERIZATION OF PARTICULATE EMISSIONS FROM CONTROLLED CONSTRUCTION ACTIVITIES: MUD/DIRT CARRYOUT
The report describes a field study of PM-2.5 and PM-10 (particulate matter with aerodynamic diameter less than 2.5 and 10 micrometers, respectively) emissions from a public paved road in Overland Park, Kansas, adjacent to a 200-acre construction site which will ultimately have 4 ...
The physicochemical properties of coarse-mode, iron-containing particles, and their temporal and spatial distributions are poorly understood. Single particle analysis combining x-ray elemental mapping and computer-controlled scanning electron microscopy (CCSEM-EDX) of passively ...
Residential, personal, indoor, and outdoor sampling of particulate matter was conducted at a retirement center in the Towson area of northern Baltimore County in 1998. Concurrent sampling was conducted at a central community site. Computer-controlled scanning electron microsco...
Characterization of cotton gin particulate matter emissions – project plan
USDA-ARS?s Scientific Manuscript database
In 2006, EPA implemented a more stringent standard for particulate matter with an effective diameter less than 2.5 microns (PM2.5). The implementation timeline for this standard will vary by state/district regulatory agency. For example, the San Joaquin Valley Air Pollution Control District, has pro...
Characterization of cotton gin particulate matter emissions - project plan
USDA-ARS?s Scientific Manuscript database
In 2006, EPA implemented a more stringent standard for particulate matter with an effective diameter less than 2.5 microns (PM2.5). The implementation time line for this standard will vary by state/district regulatory agency. For example, the San Joaquin Valley Air Pollution Control District has pro...
40 CFR 49.128 - Rule for limiting particulate matter emissions from wood products industry sources.
Code of Federal Regulations, 2010 CFR
2010-07-01
... emissions from wood products industry sources. 49.128 Section 49.128 Protection of Environment ENVIRONMENTAL... Rule for limiting particulate matter emissions from wood products industry sources. (a) What is the... certain wood products industry sources operating within the Indian reservation to control ground-level...
Improved methods for measuring and assessing microenvironmental exposure in individuals are needed. How human activities affect particulate matter in the personal cloud is poorly understood. A quality assurance tool to aid the study of particle transport mechanisms (e.g., re-en...
A multi-factor designation method for mapping particulate-pollution control zones in China.
Qin, Y; Xie, S D
2011-09-01
A multi-factor designation method for mapping particulate-pollution control zones was brought out through synthetically considering PM(10) pollution status, PM(10) anthropogenic emissions, fine particle pollution, long-range transport and economic situation. According to this method, China was divided into four different particulate-pollution control regions: PM Suspended Control Region, PM(10) Pollution Control Region, PM(2.5) Pollution Control Region and PM(10) and PM(2.5) Common Control Region, which accounted for 69.55%, 9.66%, 4.67% and 16.13% of China's territory, respectively. The PM(10) and PM(2.5) Common Control Region was mainly distributed in Bohai Region, Yangtze River Delta, Pearl River Delta, eastern of Sichuan province and Chongqing municipality, calling for immediate control of both PM(10) and PM(2.5). Cost-effective control effects can be achieved through concentrating efforts on PM(10) and PM(2.5) Common Control Region to address 60.32% of national PM(10) anthropogenic emissions. Air quality in districts belonging to PM(2.5) Pollution Control Region suggested that Chinese national ambient air quality standard for PM(10) was not strict enough. The result derived from application to China proved that this approach was feasible for mapping pollution control regions for a country with vast territory, complicated pollution characteristics and limited available monitoring data. Copyright © 2011 Elsevier B.V. All rights reserved.
Liu, Qichen; Huang, Jing; Guo, Bin; Guo, Xinbiao
2016-12-28
Background : The Asia-Pacific Economic Cooperation (APEC) meeting was held from 5 November to 11 November 2014 in Beijing, and comprehensive emission control measures were implemented. The efficiency of these measures on particulate matter-related health impacts and economic cost need to be evaluated. Methods : The influences of emission control measures during APEC on particulate matter were evaluated, and health economic effects were assessed. Results : Average concentrations of PM 2.5 and PM 10 during APEC were reduced by 57.0%, and 50.6% respectively, compared with pre-APEC period. However, the concentrations of particulate matter rebounded after APEC. Compared with the pre-APEC and post-APEC periods, the estimated number of deaths caused by non-accidental, cardiovascular and respiratory diseases that could be attributed to PM 2.5 and PM 10 during the APEC were the lowest. The economic cost associated with mortality caused by PM 2.5 and PM 10 during the APEC were reduced by (61.3% and 66.6%) and (50.3% and 60.8%) respectively, compared with pre-APEC and post-APEC. Conclusions : The emission control measures were effective in improving short term air quality and reducing health risks and medical expenses during 2014 APEC, but more efforts is needed for long term and continuous air quality improvement and health protection.
Liu, Qichen; Huang, Jing; Guo, Bin; Guo, Xinbiao
2016-01-01
Background: The Asia-Pacific Economic Cooperation (APEC) meeting was held from 5 November to 11 November 2014 in Beijing, and comprehensive emission control measures were implemented. The efficiency of these measures on particulate matter-related health impacts and economic cost need to be evaluated. Methods: The influences of emission control measures during APEC on particulate matter were evaluated, and health economic effects were assessed. Results: Average concentrations of PM2.5 and PM10 during APEC were reduced by 57.0%, and 50.6% respectively, compared with pre-APEC period. However, the concentrations of particulate matter rebounded after APEC. Compared with the pre-APEC and post-APEC periods, the estimated number of deaths caused by non-accidental, cardiovascular and respiratory diseases that could be attributed to PM2.5 and PM10 during the APEC were the lowest. The economic cost associated with mortality caused by PM2.5 and PM10 during the APEC were reduced by (61.3% and 66.6%) and (50.3% and 60.8%) respectively, compared with pre-APEC and post-APEC. Conclusions: The emission control measures were effective in improving short term air quality and reducing health risks and medical expenses during 2014 APEC, but more efforts is needed for long term and continuous air quality improvement and health protection. PMID:28036006
REGIONAL CARDIAC BLOOD FLOW WITH AIR PARTICLE EXPOSURE
This proposal offers the unique application of novel techniques to improve understanding of the mechanisms whereby ambient particulate exerts deleterious influences on the heart and circulation. Enhanced ischemia has broad implications for cardiac morbidity and mor...
ERIC Educational Resources Information Center
Steucek, G. L.; Yurkiewicz, W. J.
1973-01-01
Describes a hydroponic culture technique suitable for student exercises in biology. This technique of growing plants in nutrient solutions enhances plant growth, and is an excellent way to obtain intact plants with root systems free of soil or other particulate matter. (JR)
NASA Astrophysics Data System (ADS)
Wu, X.-L.; Wu, H.; Wang, Z.-M.; Aizawa, H.; Guo, J.; Chu, Y.-H.
2017-04-01
Herein, debris particulates of nanoporous silver (np-Ag) were synthesised by a dealloying method, and their integration behaviour and surface-enhanced Raman scattering (SERS) properties during iodine functionalisation were examined. It was found that the dealloyed np-Ag debris particulates gradually assembled to form rigid nanoporous microspheres comprising Ag nano-ligaments due to mechanical collisions during iodine treatment. High-resolution transmission electron microscopy and X-ray photoelectron microscopy clearly showed the iodide surface of np-Ag, which was dotted with iodine or iodide ‘nanoislands’. The exceptional, and unexpected, integration and surface structures result in a highly enhanced localised surface plasmon resonance. Furthermore, the robust nanoporous microspheres can be employed individually as as-produced miniaturised electrodes to electrically enrich target molecules at parts-per-trillion levels, so as to achieve charge selectivity and superior detectability compared with the ordinary SERS effect.
Micro/nanoparticle adjuvants for antileishmanial vaccines: present and future trends.
Badiee, Ali; Heravi Shargh, Vahid; Khamesipour, Ali; Jaafari, Mahmoud Reza
2013-01-21
Leishmania infection continues to have a major impact on public health inducing significant morbidity and mortality mostly in the poorest populations. Drug resistance, toxicity and side effects associated with expensive chemotherapeutic treatments and difficult reservoir control emphasize the need for a safe and effective vaccine which is not available yet. Although, Leishmanization (LZ) was shown to be effective against cutaneous leishmaniasis, standardization and safety are the main problems of LZ. First generation killed parasites demonstrated limited efficacy in phase 3 trials and moreover well defined molecules have not reached to phase 3 yet. Limited efficacy in vaccines against leishmaniasis is partly due to lack of an appropriate adjuvant. Hence, the use of particulate delivery systems as carriers for antigen and/or immunostimulatory adjuvants for effective delivery to the antigen-presenting cells (APCs) is a valuable strategy to enhance vaccine efficacies. Particle-based delivery systems such as emulsions, liposomes, virosomes, and polymeric microspheres have the potential for successfully delivering antigens, which can then be further improved via incorporation of additional antigenic or immustimulatory adjuvant components in or onto the particle carrier system. In this review, we have attempted to provide a list of particulate vaccine delivery systems involved in the production of candidate leishmaniasis vaccines and introduced some potentially useful vaccine delivery systems for leishmaniasis in future experiments. In conclusion, combination vaccines (adjuvant systems) composed of candidate antigens and more importantly well-developed particulate delivery systems, such as lipid-based particles containing immunostimulatory adjuvants, have a chance to succeed as antileishmanial vaccines. Copyright © 2012 Elsevier Ltd. All rights reserved.
Further Examination of Biogeochemical Consequences of Mesoscale Eddies in the Sargasso Sea
NASA Astrophysics Data System (ADS)
Marquez, I. A., Jr.; Krause, J. W.; Lomas, M. W.
2016-02-01
The Bermuda Atlantic Time Series (BATS) is an ongoing 25-year biogeochemical record in the North Atlantic subtropical gyre. Contemporaneous data on the particulate phases of four major bioreactive elements, C, N, P, and Si only exist during two years and also for a companion project (Trophic BATS, i.e. TBATS). A combined dataset from BATS and TBATS was used to better understand the coupling of C, N, P, and Si in the Sargasso Sea by analyzing particulate phases of each element in the water column and exported material. Three conclusions are inferred: first, the effect of mesoscale eddies on standing stocks, export rates, and elemental coupling of C, N, P, and Si displays strong seasonality. Statistically significant differences between particulate water column and export ratios using internal and between site comparisons were robust in the summer only. Second, N, Si and particularly P were more efficiently recycled within the euphotic zones of eddies as elemental ratios in export material were greater than the corresponding ratios in the water column. This suggests that P may have a more critical biogeochemical role and its supply rate to the euphotic zone may control primary production in these closed systems. Third, the trends seen in these eddies do not support that export production was enhanced, instead these features had more efficient recycling of N, P, and Si relative to the BATS site. This decrease in export efficiency suggests a stimulation of export production above 'normal' BATS conditions within eddies would require significantly higher autotrophic standing stock and correspondingly high rates of organic matter production.
[Distribution characteristics of particulate mercury in aerosol in coastal city].
Zhang, Fu-Wang; Zhao, Jin-Ping; Chen, Jin-Sheng; Xu, Ya
2010-10-01
Particulate mercury, which is bound with aerosol in atmosphere, has a negative impact on human health and the environment, also plays an important role in the biogeochemical process of mercury. In this paper, taking southeast coastal city of Xiamen as research object, the PM2.5, PM10 and TSP were collected in residential, tourism, industrial area and background, respectively, during four seasons (October 2008-September 2009). RA-915 + mercury analyzer was employed to determinate mercury concentration in different size particle matters based on zeeman atomic absorption spectrometry. The results showed that the contents of particulate mercury in different size of aerosol during Winter, Spring were obviously higher than that of Summer, Autumn; the concentrations of particulate mercury in fine particle during Spring, Summer, Autumn and Winter were (51.46 +/- 19.28), (42.41 +/- 12.74), (38.38 +/- 6.08) and (127.23 +/- 33.70) pg/m3, respectively. The experimental data showed that the particulate mercury were mainly distributed in fine particles (PM2.5), which covered 42.48%-67.87%, and it can be concluded that the rate of particulate mercury enrichment in coarse particle was much lower than that of fine particle. The sequence of atmospheric particulate mercury concentration in different functional areas was: background < resident < tourism < industrial area < suburban; which showed characteristics of spatial distribution of particulate mercury was affected by the sampling location. On the whole, Xiamen had a low level of atmospheric particulate mercury; the enrichment of PM2.5 to particulate mercury was significantly higher than that of PM10 and TSP, and showed that fine particle pollution should be tightly controlled to reduce particulate mercury.
NASA Astrophysics Data System (ADS)
Nakaya, Shinji; Chi, Hai; Muroda, Kengo; Masuda, Harue
2018-06-01
In this study, we focus on the behavior of geogenic, toxic trace elements, particularly As, Cs, Cd, and Pb, during their transportation in two rivers for irrigation commonly used in monsoon Asia; one river originates from an active volcano, Mt. Asama, and the other originates from a currently inactive volcano, Yatsugatake Mountains in Nagano, Japan. These rivers were investigated to understand the role of river water as a pollutant of rice and other aquatic plants (via irrigation) and aquatic animals. The results indicated that the behavior of toxic trace elements in river water are likely controlled by their interactions with particulate Fe, Al, and Ti compounds. The majority of Pb and Cd is transported as particulate matter with Fe, Al, and Ti, while the majority of As is transported in the dissolved form, predominantly as arsenate, with low abundance of particulate matter. Cs is transported either as the dissolved form or as particulate matter in both rivers. The investigated elements are transported in the rivers as particulate and dissolved forms, and the ratio of these forms is controlled by the pH and presence of particulate Fe, Al, and Ti phases in the river water. With respect to Cs in both rivers, the parameter governing the concentration and transportation of Cs, in the bimodal form (i.e., particulate and dissolved forms), through the river possibly shifts from sorption to pH by particulate Fe-Al-Ti, according to the abrupt increase in the concentration of Cs in the river. The chemical attraction of particulate Fe-Al-Ti for Cs is weaker than that for Pb and Cd, indicating that the lower electronegativity of Cs weakens the chemical attraction on a colloid for the competitive sorption with the other trace elements. The different relationships between As and Fe in the river and in the irrigation water and soil water, as well as those in paddy rice, suggested that As in paddy rice is not directly derived from As in the irrigation water from the river under flooding.
Binder enhanced refuse derived fuel
Daugherty, Kenneth E.; Venables, Barney J.; Ohlsson, Oscar O.
1996-01-01
A refuse derived fuel (RDF) pellet having about 11% or more particulate calcium hydroxide which is utilized in a combustionable mixture. The pellets are used in a particulate fuel bring a mixture of 10% or more, on a heat equivalent basis, of the RDF pellet which contains calcium hydroxide as a binder, with 50% or more, on a heat equivalent basis, of a sulphur containing coal. Combustion of the mixture is effective to produce an effluent gas from the combustion zone having a reduced SO.sub.2 and polycyclic aromatic hydrocarbon content of effluent gas from similar combustion materials not containing the calcium hydroxide.
Rumen conditions that predispose cattle to pasture bloat.
Majak, W; Howarth, R E; Cheng, K J; Hall, J W
1983-08-01
Rumen contents from the dorsal sac were examined before alfalfa ingestion to determine factors that predispose cattle to pasture bloat. Chlorophyll concentration, buoyancy of particulate matter, and rates of gas production were significantly higher in cattle that subsequently bloated than in those that did not. Higher chlorophyll in bloat cases indicated accumulation of suspended chloroplast particles in the dorsal sac, perhaps due to increased buoyancy of the particulate matter. The higher fermentation rates (in the presence of glucose) suggested that the latent capacity for gas production was due to microbial colonization of suspended feed particles. Chlorophyll 4 h after feeding was also higher in bloated as compared to unbloated animals. In short, the microbial colonization and retention of particulate matter provided active inocula for promoting rapid legume digestion. Consequently, gas production was enhanced when feeding commenced, but the fermentation gases were trapped by the buoyant, frothy ingesta, resulting in the condition of pasture bloat.
Lee, Ji Yeon
2016-10-01
Transmission of tuberculosis (TB) is a recognized risk to patients and healthcare workers in healthcare settings. The literature review suggests that implementation of combination control measures reduces the risk of TB transmission. Guidelines suggest a three-level hierarchy of controls including administrative, environmental, and respiratory protection. Among environmental controls, installation of ventilation systems is a priority because ventilation reduces the number of infectious particles in the air. Natural ventilation is cost-effective but depends on climatic conditions. Supplemented intervention such as air-cleaning methods including high efficiency particulate air filtration and ultraviolet germicidal irradiation should be considered in areas where adequate ventilation is difficult to achieve. Personal protective equipment including particulate respirators provides additional benefit when administrative and environmental controls cannot assure protection.
Combustor for fine particulate coal
Carlson, L.W.
1988-01-26
A particulate coal combustor with two combustion chambers is provided. The first combustion chamber is toroidal; air and fuel are injected, mixed, circulated and partially combusted. The air to fuel ratio is controlled to avoid production of soot or nitrogen oxides. The mixture is then moved to a second combustion chamber by injection of additional air where combustion is completed and ash removed. Temperature in the second chamber is controlled by cooling and gas mixing. The clean stream of hot gas is then delivered to a prime mover. 4 figs.
Combustor for fine particulate coal
Carlson, Larry W.
1988-01-01
A particulate coal combustor with two combustion chambers is provided. The first combustion chamber is toroidal; air and fuel are injected, mixed, circulated and partially combusted. The air to fuel ratio is controlled to avoid production of soot or nitrogen oxides. The mixture is then moved to a second combustion chamber by injection of additional air where combustion is completed and ash removed. Temperature in the second chamber is controlled by cooling and gas mixing. The clean stream of hot gas is then delivered to a prime mover.
Combustor for fine particulate coal
Carlson, L.W.
1988-11-08
A particulate coal combustor with two combustion chambers is provided. The first combustion chamber is toroidal; air and fuel are injected, mixed, circulated and partially combusted. The air to fuel ratio is controlled to avoid production of soot or nitrogen oxides. The mixture is then moved to a second combustion chamber by injection of additional air where combustion is completed and ash removed. Temperature in the second chamber is controlled by cooling and gas mixing. The clean stream of hot gas is then delivered to a prime mover. 4 figs.
40 CFR 49.128 - Rule for limiting particulate matter emissions from wood products industry sources.
Code of Federal Regulations, 2013 CFR
2013-07-01
... emissions from wood products industry sources. 49.128 Section 49.128 Protection of Environment ENVIRONMENTAL... Region 10 § 49.128 Rule for limiting particulate matter emissions from wood products industry sources. (a... emitted from certain wood products industry sources operating within the Indian reservation to control...
40 CFR 49.128 - Rule for limiting particulate matter emissions from wood products industry sources.
Code of Federal Regulations, 2012 CFR
2012-07-01
... emissions from wood products industry sources. 49.128 Section 49.128 Protection of Environment ENVIRONMENTAL... Region 10 § 49.128 Rule for limiting particulate matter emissions from wood products industry sources. (a... emitted from certain wood products industry sources operating within the Indian reservation to control...
Performance characteristics of a low-volume PM10 sampler
USDA-ARS?s Scientific Manuscript database
Four identical PM10 pre-separators, along with four identical low-volume (1m3 hr-1) total suspended particulate (TSP) samplers were tested side-by-side in a controlled laboratory particulate matter (PM) chamber. The four PM10 and four TSP samplers were also tested in an oil pipe-cleaning field to ev...
Air pollution in the form of particulate matter (PM) originates from both human activities and "natural" phenomena. Setting and achieving National Ambient Air Quality Standards (NAAQS) for PM has to take into account the latter since they are in general less controllable than th...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-01-07
...)(2).) List of Subjects in 40 CFR Part 52 Environmental protection, Air pollution control... 2011 ambient air quality data, the Philadelphia-Wilmington, PA-NJ-DE fine particulate matter (PM 2.5... 2011 ambient air quality data, the Philadelphia-Wilmington, PA-NJ-DE fine particulate matter (PM 2.5...
40 CFR 266.105 - Standards to control particulate matter.
Code of Federal Regulations, 2011 CFR
2011-07-01
... standard cubic foot) after correction to a stack gas concentration of 7% oxygen, using procedures... particulate matter standard. (c) Oxygen correction. (1) Measured pollutant levels must be corrected for the amount of oxygen in the stack gas according to the formula: ER30SE99.027 Where: Pc is the corrected...
40 CFR 266.105 - Standards to control particulate matter.
Code of Federal Regulations, 2013 CFR
2013-07-01
... standard cubic foot) after correction to a stack gas concentration of 7% oxygen, using procedures... particulate matter standard. (c) Oxygen correction. (1) Measured pollutant levels must be corrected for the amount of oxygen in the stack gas according to the formula: ER30SE99.027 Where: Pc is the corrected...
40 CFR 266.105 - Standards to control particulate matter.
Code of Federal Regulations, 2012 CFR
2012-07-01
... standard cubic foot) after correction to a stack gas concentration of 7% oxygen, using procedures... particulate matter standard. (c) Oxygen correction. (1) Measured pollutant levels must be corrected for the amount of oxygen in the stack gas according to the formula: ER30SE99.027 Where: Pc is the corrected...
40 CFR 266.105 - Standards to control particulate matter.
Code of Federal Regulations, 2014 CFR
2014-07-01
... standard cubic foot) after correction to a stack gas concentration of 7% oxygen, using procedures... particulate matter standard. (c) Oxygen correction. (1) Measured pollutant levels must be corrected for the amount of oxygen in the stack gas according to the formula: ER30SE99.027 Where: Pc is the corrected...
40 CFR 49.128 - Rule for limiting particulate matter emissions from wood products industry sources.
Code of Federal Regulations, 2011 CFR
2011-07-01
... emissions from wood products industry sources. 49.128 Section 49.128 Protection of Environment ENVIRONMENTAL... Region 10 § 49.128 Rule for limiting particulate matter emissions from wood products industry sources. (a... emitted from certain wood products industry sources operating within the Indian reservation to control...
2003-08-29
KENNEDY SPACE CENTER, FLA. - A KSC employee uses a clean-air shower before entering a clean room. Streams of pressurized air directed at the occupant from nozzles in the chamber's ceiling and walls are designed to dislodge particulate matter from hair, clothing and shoes. The adhesive mat on the floor captures soil from shoe soles, as well as particles that fall on its surface. Particulate matter has the potential to contaminate the space flight hardware being stored or processed in the clean room. The shower is part of KSC's Foreign Object Debris (FOD) control program, an important safety initiative.
Mokhtar, Helen; Biffar, Lucia; Somavarapu, Satyanarayana; Frossard, Jean-Pierre; McGowan, Sarah; Pedrera, Miriam; Strong, Rebecca; Edwards, Jane C; Garcia-Durán, Margarita; Rodriguez, Maria Jose; Stewart, Graham R; Steinbach, Falko; Graham, Simon P
2017-09-01
PRRS control is hampered by the inadequacies of existing vaccines to combat the extreme diversity of circulating viruses. Since immune clearance of PRRSV infection may not be dependent on the development of neutralising antibodies and the identification of broadly-neutralising antibody epitopes have proven elusive, we hypothesised that conserved T cell antigens represent potential candidates for development of a novel PRRS vaccine. Previously we had identified the M and NSP5 proteins as well-conserved targets of polyfunctional CD8 and CD4 T cells. To assess their vaccine potential, peptides representing M and NSP5 were encapsulated in hydrophobically-modified chitosan particles adjuvanted by incorporation of a synthetic multi-TLR2/TLR7 agonist and coated with a model B cell PRRSV antigen. For comparison, empty particles and adjuvanted particles encapsulating inactivated PRRSV-1 were prepared. Vaccination with the particulate formulations induced antigen-specific antibody responses, which were most pronounced following booster immunisation. M and NSP5-specific CD4, but not CD8, T cell IFN-γ reactivity was measurable following the booster immunisation in a proportion of animals vaccinated with peptide-loaded particles. Upon challenge, CD4 and CD8 T cell reactivity was detected in all groups, with the greatest responses being detected in the peptide vaccinated group but with limited evidence of an enhanced control of viraemia. Analysis of the lungs during the resolution of infection showed significant M/NSP5 specific IFN-γ responses from CD8 rather than CD4 T cells. Vaccine primed CD8 T cell responses may therefore be required for protection and future work should focus on enhancing the cross-presentation of M/NSP5 to CD8 T cells. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.
On-Board Particulate Filter Failure Prevention and Failure Diagnostics Using Radio Frequency Sensing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sappok, Alex; Ragaller, Paul; Herman, Andrew
The increasing use of diesel and gasoline particulate filters requires advanced on-board diagnostics (OBD) to prevent and detect filter failures and malfunctions. Early detection of upstream (engine-out) malfunctions is paramount to preventing irreversible damage to downstream aftertreatment system components. Such early detection can mitigate the failure of the particulate filter resulting in the escape of emissions exceeding permissible limits and extend the component life. However, despite best efforts at early detection and filter failure prevention, the OBD system must also be able to detect filter failures when they occur. In this study, radio frequency (RF) sensors were used to directlymore » monitor the particulate filter state of health for both gasoline particulate filter (GPF) and diesel particulate filter (DPF) applications. The testing included controlled engine dynamometer evaluations, which characterized soot slip from various filter failure modes, as well as on-road fleet vehicle tests. The results show a high sensitivity to detect conditions resulting in soot leakage from the particulate filter, as well as potential for direct detection of structural failures including internal cracks and melted regions within the filter media itself. Furthermore, the measurements demonstrate, for the first time, the capability to employ a direct and continuous monitor of particulate filter diagnostics to both prevent and detect potential failure conditions in the field.« less
NASA Astrophysics Data System (ADS)
Kleeman, Michael J.; Ying, Qi; Kaduwela, Ajith
The effect of NO x, volatile organic compound (VOC), and NH 3 emissions control programs on the formation of particulate ammonium nitrate in the San Joaquin Valley (SJV) was examined under the typical winter conditions that existed on 4-6 January, 1996. The UCD/CIT photochemical transport model was used for this study so that the source origin of primary particulate matter and secondary particulate matter could be identified. When averaged across the entire SJV, the model results predict that 13-18% of the reactive nitrogen (NO y=NO x+reaction products of NO x) emitted from local sources within the SJV was converted to nitrate at the ground level. Each gram of NO x emitted locally within the SJV (expressed as NO 2) produced 0.23-0.31 g of particulate ammonium nitrate (NH 4NO 3), which is much smaller than the maximum theoretical yield of 1.7 g of NH 4NO 3 per gram of NO 2. The fraction of reactive nitrogen converted to nitrate varied strongly as a function of location. Urban regions with large amounts of fresh NO emissions converted little reactive nitrogen to nitrate, while remote areas had up to 70% conversion (equivalent to approximately 1.2 g of NH 4NO 3 per gram of NO 2). The use of a single spatially averaged ratio of NH 4NO 3/NO x as a predictor of how changes to NO x emissions would affect particulate nitrate concentrations would not be accurate at all locations in the SJV under the conditions studied. The largest local sources of particulate nitrate in the SJV were predicted to be diesel engines and catalyst equipped gasoline engines under the conditions experienced on 6 January, 1996. Together, these sources accounted for less than half of the ground-level nitrate aerosol in the SJV. The remaining fraction of the aerosol nitrate originated from reactive nitrogen originally released upwind of the SJV. The majority of this upwind reactive nitrogen was already transformed to nitrate by the time it entered the SJV. The effect of local emissions controls on this upwind material was small. A 50% reduction in NO x emissions applied to sources within the SJV reduced the predicted concentration of total nitrate by approximately 25% during the study episode. VOC emissions controls were less effective, while reasonable NH 3 emissions controls had the smallest effect on the amount of ammonium nitrate produced. A 50% reduction in VOC emissions lowered predicted concentrations of total nitrate by 17.5%, while a 50% reduction in NH 3 emissions lowered predicted concentrations of total nitrate by only 10%. This latter result is expected since the formation of ammonium nitrate aerosol is limited by the availability of gas-phase nitric acid, with large amounts of excess NH 3 available. NO x emissions controls appear to be the most efficient method to reduce the concentration of locally generated particulate nitrate in the SJV under the conditions experienced on 4-6 January, 1996.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zaveri, Rahul A.; Berkowitz, Carl M.; Brechtel, Fred J.
Chemical evolution of aerosols and trace gases in the Salem Harbor power plant plume was monitored with the DOE G-1 aircraft on the night of July 30-31, 2002. Quasi-Lagrangian sampling in the plume at increasing downwind distances/processing times was guided by a constant-volume tetroon that was released near the power plant at sunset. While no evidence of fly ash particles was found, concentrations of particulate organics, sulfate, and nitrate were higher in the plume than in the nearby background air. These species were internally mixed and the particles were acidic, suggesting that particulate nitrate was in the form of organicmore » nitrate. The enhanced particulate organic and nitrate masses in the plume were inferred to be as secondary organic aerosol, possibly formed from the NO3 radical-initiated oxidation of isoprene and other trace organic gases in the presence of acidic sulfate particles. The enhanced particulate sulfate concentrations observed in the plume were attributed to direct emissions of gaseous SO3/H2SO4 from the power plant. Furthermore, concentration of nucleation mode particles was significantly higher in the plume than in background air, suggesting that some of the emitted H2SO4 had nucleated to form new particles. Spectromicroscopic analyses of particle samples suggested that some sulfate was likely in the form of organosulfates. Constrained Lagrangian model analysis of the aircraft and tetroon observations showed that heterogeneous hydrolysis of N2O5 was negligibly slow. These results have significant implications for several scientific and regulatory issues related to the impacts of power plant emissions on atmospheric chemistry, air quality, visibility, and climate.« less
NASA Astrophysics Data System (ADS)
Mochizuki, Tomoki; Kawamura, Kimitaka; Nakamura, Shinnosuke; Kanaya, Yugo; Wang, Zifa
2017-12-01
To understand the source and atmospheric behaviour of low molecular weight monocarboxylic acids (monoacids), gaseous (G) and particulate (P) organic acids were collected at the summit of Mt. Tai in the North China Plain (NCP) during field burning of agricultural waste (wheat straw). Particulate organic acids were collected with neutral quartz filter whereas gaseous organic acids were collected with KOH-impregnated quartz filter. Normal (C1-C10), branched (iC4-iC6), hydroxy (lactic and glycolic), and aromatic (benzoic) monoacids were determined with a capillary gas chromatography employing p-bromophenacyl esters. We found acetic acid as the most abundant gas-phase species whereas formic acid is the dominant particle-phase species. Concentrations of formic (G/P 1 570/1 410 ng m-3) and acetic (3 960/1 120 ng m-3) acids significantly increased during the enhanced field burning of agricultural wastes. Concentrations of formic and acetic acids in daytime were found to increase in both G and P phases with those of K+, a field-burning tracer (r = 0.32-0.64). Primary emission and secondary formation of acetic acid is linked with field burning of agricultural wastes. In addition, we found that particle-phase fractions (Fp = P/(G + P)) of formic (0.50) and acetic (0.31) acids are significantly high, indicating that semi-volatile organic acids largely exist as particles. Field burning of agricultural wastes may play an important role in the formation of particulate monoacids in the NCP. High levels (917 ng m-3) of particle-phase lactic acid, which is characteristic of microorganisms, suggest that microbial activity associated with terrestrial ecosystem significantly contributes to the formation of organic aerosols.
Composition of water and suspended sediment in streams of urbanized subtropical watersheds in Hawaii
De Carlo, E. H.; Beltran, V.L.; Tomlinson, M.S.
2004-01-01
Urbanization on the small subtropical island of Oahu, Hawaii provides an opportunity to examine how anthropogenic activity affects the composition of material transferred from land to ocean by streams. This paper investigates the variability in concentrations of trace elements (Pb, Zn, Cu, Ba, Co, As, Ni, V and Cr) in streams of watersheds on Oahu, Hawaii. The focus is on water and suspended particulate matter collected from the Ala Wai Canal watershed in Honolulu and also the Kaneohe Stream watershed. As predicted, suspended particulate matter controls most trace element transport. Elements such as Pb, Zn, Cu, Ba and Co exhibit increased concentrations within urbanized portions of the watersheds. Particulate concentrations of these elements vary temporally during storms owing to input of road runoff containing elevated concentrations of elements associated with vehicular traffic and other anthropogenic activities. Enrichments of As in samples from predominantly conservation areas are interpreted as reflecting agricultural use of fertilizers at the boundaries of urban and conservation lands. Particulate Ni, V and Cr exhibit distributions during storm events that suggest a mineralogical control. Principal component analysis of particulate trace element concentrations establishes eigenvalues that account for nearly 80% of the total variance and separates trace elements into 3 factors. Factor 1 includes Pb, Zn, Cu, Ba and Co, interpreted to represent metals with an urban anthropogenic enrichment. Factor 2 includes Ni, V and Cr, elements whose concentrations do not appear to derive from anthropogenic activity and is interpreted to reflect mineralogical control. Another, albeit less significant, anthropogenic factor includes As, Cd and U and is thought to represent agricultural inputs. Samples collected during a storm derived from an offshore low-pressure system suggest that downstream transport of upper watershed material during tradewind-derived rains results in a 2-3-fold dilution of the particulate concentrations of Pb, Zn and Cu in the Ala Wai canal watershed. ?? 2004 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Khodse, Vishwas B.; Bhosle, Narayan B.
2013-10-01
Amino sugars including bacterial biomarker muramic acid (Mur) were investigated in suspended particulate matter (SPM) to understand their distribution, origin, and biogeochemical cycling and the contribution of bacteria to particulate organic matter (POM) of the Mandovi estuary. SPM was collected from 9 sampling stations in the Mandovi estuary during the pre-monsoon (March) and monsoon (August). Total particulate amino sugar (TPAS) concentrations and yields varied spatially and were 2 to 5 times higher during the monsoon than the pre-monsoon. Negative correlation between salinity and TPAS-C yields [TPAS-C/particulate organic carbon (POC)×100] indicates the influence of terrestrial organic matter on the transport of TPAS-carbon. Glucosamine (GlcN), galactosamine (GalN), and mannosamine (ManN) were abundant during the monsoon. Low GlcN/GalN ratios (<3) indicate bacteria as the major source of amino sugars. Higher amino sugar yields and lower GlcN/GalN ratios during the monsoon than the pre-monsoon indicate enhanced transformation and greater bacterial contribution to POM during the former season. Degradation trends observed with TPAS were well supported by those obtained with carbohydrates and amino acids. Based on Mur concentrations, bacteria accounted for 24% to 35% of the POC and 24% to 62% of the total particulate nitrogen (TPN). Intact bacterial cells, however accounted for a small proportion of POC (2.5% to 4%) and TPN (9% to 11%). Our study suggests that POM was subjected to extensive diagenetic transformation, and its composition was influenced by bacteria, especially during the monsoon.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yanamala, Naveena, E-mail: wqu1@cdc.gov; Hatfield, Meghan K., E-mail: wla4@cdc.gov; Farcas, Mariana T., E-mail: woe7@cdc.gov
2013-10-15
The use of biodiesel (BD) or its blends with petroleum diesel (D) is considered to be a viable approach to reduce occupational and environmental exposures to particulate matter (PM). Due to its lower particulate mass emissions compared to D, use of BD is thought to alleviate adverse health effects. Considering BD fuel is mainly composed of unsaturated fatty acids, we hypothesize that BD exhaust particles could induce pronounced adverse outcomes, due to their ability to readily oxidize. The main objective of this study was to compare the effects of particles generated by engine fueled with neat BD and neat petroleum-basedmore » D. Biomarkers of tissue damage and inflammation were significantly elevated in lungs of mice exposed to BD particulates. Additionally, BD particulates caused a significant accumulation of oxidatively modified proteins and an increase in 4-hydroxynonenal. The up-regulation of inflammatory cytokines/chemokines/growth factors was higher in lungs upon BD particulate exposure. Histological evaluation of lung sections indicated presence of lymphocytic infiltrate and impaired clearance with prolonged retention of BD particulate in pigment laden macrophages. Taken together, these results clearly indicate that BD exhaust particles could exert more toxic effects compared to D. - Highlights: • Exposure of mice to BDPM caused higher pulmonary toxicity compared to DPM. • Oxidative stress and inflammation were higher in BD vs to D exposed mice. • Inflammatory lymphocyte infiltrates were seen only in lungs of mice exposed to BD. • Ineffective clearance, prolonged PM retention was present only after BD exposure.« less
NASA Astrophysics Data System (ADS)
Matsumoto, Kiyoshi; Minami, Hideki; Hayano, Teruaki; Uyama, Yukiko; Tanimoto, Hiroshi; Uematsu, Mitsuo
2007-12-01
A year-round observation of atmospheric aerosols and their associated species was conducted from March 2001 to May 2002 on Rishiri Island in the northern area of the east Asian Pacific rim region. Asian outflows brought continental air masses to this area during the period from the autumn to the spring although marine air masses from the high-latitudinal ocean often broke into this area during the midwinter. In contrast, marine air masses were predominant over this area in the summer. Particulate elemental carbon (EC) would be mainly transported with biomass smoke particles, and seasonal variation in its concentrations was well correlated with the air mass alternation, showing higher concentrations during the period from the autumn to the spring with some decreases in the midwinter. The concentrations of particulate organic carbon (OC) showed a similar seasonal trend with those of the particulate EC, but relatively high concentrations were found in the summer due to photochemical secondary productions. The particulate OC that is vaporized by heating at higher temperatures (OCHT) would be mainly carried with the biomass smoke, and the particulate OC that is vaporized at lower temperatures (OCLT) would be mainly caused by secondary production processes. Summer enhancements of the secondary species, such as OC and nss-SO42-, caused decreases in the ratio of EC/PM2.5, which would contribute to the high single scattering albedo of fine aerosols in the summer. Aerosols in the Asian outflows in this area are relatively "black" in the winter, although the aerosol mass loading increases in the spring.
Size and chemical characterization of airborne particulate matter in Spokane
DOE Office of Scientific and Technical Information (OSTI.GOV)
Haller, L.; Claiborn, C.; Westberg, H.
1996-12-31
Recent health effects studies suggest that the present air quality standard for aerosols, which is based upon respirable particles, does not adequately protect public health; Thus the standard is currently under review. In July, 1994, a comprehensive study was initiated in Spokane to study the relationship between various size fractions and chemical components of atmospheric aerosol and health effects. This study is one of the most comprehensive particulate matter studies conducted to date, and is one of a limited number of studies that have been conducted in the and west, where presumably a significant portion of the aerosol will bemore » derived from geological materials. Continuous fine and coarse particulate matter measurements are made at two location (one is in industrial area, and the other in residential area). At the residential site, particulate matter smaller than 1.0 {mu}m, and ultra fine particles are also continuously monitored, and analyzed for a variety of chemical species including elemental components, ionic species, soluble iron, elemental and organic carbon and acidity. Preliminary results indicate that the windblown dust enhances both the fine and coarse fractions of particulate matter in Spokane. Seasonal trends in chemical composition and size characterization will be examined. The relationships between the 24-hour average values and peak hourly values, as well as differences between weekday and weekend levels, will also be discussed.« less
[Characteristic of Particulate Emissions from Concrete Batching in Beijing].
Xue, Yi-feng; Zhou, Zhen; Zhong, Lian-hong; Yan, Jing; Qu, Song; Huang, Yu-hu; Tian, He- zhong; Pan, Tao
2016-01-15
With the economic development and population growth in Beijing, there is a strong need for construction and housing, which leads to the increase of the construction areas. Meanwhile, as a local provided material, the production of concrete has been raised. In the process of concrete production by concrete batching, there are numerous particulates emitted, which have large effect on the atmospheric environment, however, systematic study about the tempo-spatial characteristics of pollutant emission from concrete batching is still rare. In this study, we estimated the emission of particulates from concrete batching from 1991 to 2012 using emission factor method, analyzed the tempo-spatial characteristics of pollutant emission, established the uncertainty range by adopting Monte-Carlo method, and predicted the future emission in 2020 based on the relative environmental and economical policies. The results showed that: (1) the emissions of particulates from concrete batching showed a trend of "first increase and then decrease", reaching the maximum in 2005, and then decreased due to stricter emission standard and enhanced environmental management. (2) according to spatial distribution, the emission of particulates from concrete batch mainly concentrated in the urban area with more human activities, and the area between the fifth ring and the sixth ring contributed the most. (3) through scenarios analysis, for further reducing the emission from concrete batching in 2020, more stricter standard for green production as well as powerful supervision is needed.
Friction Stir Processing of Copper-Coated SiC Particulate-Reinforced Aluminum Matrix Composite
Huang, Chih-Wei; Aoh, Jong-Ning
2018-01-01
In the present work, we proposed a novel friction stir processing (FSP) to produce a locally reinforced aluminum matrix composite (AMC) by stirring copper-coated SiC particulate reinforcement into Al6061 alloy matrix. Electroless-plating process was applied to deposit the copper surface coating on the SiC particulate reinforcement for the purpose of improving the interfacial adhesion between SiC particles and Al matrix. The core-shell SiC structure provides a layer for the atomic diffusion between aluminum and copper to enhance the cohesion between reinforcing particles and matrix on one hand, the dispersion of fine copper in the Al matrix during FSP provides further dispersive strengthening and solid solution strengthening, on the other hand. Hardness distribution and tensile results across the stir zone validated the novel concept in improving the mechanical properties of AMC that was realized via FSP. Optical microscope (OM) and Transmission Electron Microscopy (TEM) investigations were conducted to investigate the microstructure. Energy dispersive spectrometer (EDS), electron probe micro-analyzer (EPMA), and X-ray diffraction (XRD) were explored to analyze the atomic inter-diffusion and the formation of intermetallic at interface. The possible strengthening mechanisms of the AMC containing Cu-coated SiC particulate reinforcement were interpreted. The concept of strengthening developed in this work may open a new way of fabricating of particulate reinforced metal matrix composites. PMID:29652846
Izadifar, Mohammad; Haddadi, Azita; Chen, Xiongbiao; Kelly, Michael E
2015-01-09
Development of smart bioactive scaffolds is of importance in tissue engineering, where cell proliferation, differentiation and migration within scaffolds can be regulated by the interactions between cells and scaffold through the use of growth factors (GFs) and extra cellular matrix peptides. One challenge in this area is to spatiotemporally control the dose, sequence and profile of release of GFs so as to regulate cellular fates during tissue regeneration. This challenge would be addressed by rate-programming of nano-particulate delivery systems, where the release of GFs via polymeric nanoparticles is controlled by means of the methods of, such as externally-controlled and physicochemically/architecturally-modulated so as to mimic the profile of physiological GFs. Identifying and understanding such factors as the desired release profiles, mechanisms of release, physicochemical characteristics of polymeric nanoparticles, and externally-triggering stimuli are essential for designing and optimizing such delivery systems. This review surveys the recent studies on the desired release profiles of GFs in various tissue engineering applications, elucidates the major release mechanisms and critical factors affecting release profiles, and overviews the role played by the mathematical models for optimizing nano-particulate delivery systems. Potentials of stimuli responsive nanoparticles for spatiotemporal control of GF release are also presented, along with the recent advances in strategies for spatiotemporal control of GF delivery within tissue engineered scaffolds. The recommendation for the future studies to overcome challenges for developing sophisticated particulate delivery systems in tissue engineering is discussed prior to the presentation of conclusions drawn from this paper.
Peraza-Castro, M; Sauvage, S; Sánchez-Pérez, J M; Ruiz-Romera, E
2016-11-01
An understanding of the processes controlling sediment, organic matter and metal export is critical to assessing and anticipating risk situations in water systems. Concentrations of suspended particulate matter (SPM), dissolved (DOC) and particulate (POC) organic carbon and metals (Cu, Ni, Pb, Cr, Zn, Mn, Fe) in dissolved and particulate phases were monitored in a forest watershed in the Basque Country (Northern Spain) (31.5km(2)) over three hydrological years (2009-2012), to evaluate the effect of flood events on the transport of these materials. Good regression was found between SPM and particulate metal concentration, making it possible to compute the load during the twenty five flood events that occurred during the study period at an annual scale. Particulate metals were exported in the following order: Fe>Mn>Zn>Cr>Pb>Cu>Ni. Annual mean loads of SPM, DOC and POC were estimated at 2267t, 104t and 57t, respectively, and the load (kg) of particulate metals at 76 (Ni), 83 (Cu), 135 (Pb), 256 (Cr), 532 (Zn), 1783 (Mn) and 95170 (Fe). Flood events constituted 91%-SPM, 65%-DOC, 71%-POC, 80%-Cu, 85%-Ni, 72%-Pb, 84%-Cr, 74%-Zn, 87%-Mn and 88%-Fe of total load exported during the three years studied. Flood events were classified into three categories according to their capacity for transporting organic carbon and particulate metals. High intensity flood events are those with high transport capacity of SPM, organic carbon and particulate metals. Most of the SPM, DOC, POC and particulate metal load was exported by this type of flood event, which contributed 59% of SPM, 45% of organic carbon and 54% of metals. Copyright © 2016 Elsevier B.V. All rights reserved.
Measurement and analysis of ambient atmospheric particulate matter in urban and remote environments
NASA Astrophysics Data System (ADS)
Hagler, Gayle S. W.
Atmospheric particulate matter pollution is a challenging environmental concern in both urban and remote locations worldwide. It is intrinsically difficult to control, given numerous anthropogenic and natural sources (e.g. fossil fuel combustion, biomass burning, dust, and seaspray) and atmospheric transport up to thousands of kilometers after production. In urban regions, fine particulate matter (particles with diameters under 2.5 mum) is of special concern for its ability to penetrate the human respiratory system and threaten cardiopulmonary health. A second major impact area is climate, with particulate matter altering Earth's radiative balance through scattering and absorbing solar radiation, modifying cloud properties, and reducing surface reflectivity after deposition in snow-covered regions. While atmospheric particulate matter has been generally well-characterized in populated areas of developed countries, particulate pollution in developing nations and remote regions is relatively unexplored. This thesis characterizes atmospheric particulate matter in locations that represent the extreme ends of the spectrum in terms of air pollution-the rapidly-developing and heavily populated Pearl River Delta Region of China, the pristine and climate-sensitive Greenland Ice Sheet, and a remote site in the Colorado Rocky Mountains. In China, fine particles were studied through a year-long field campaign at seven sites surrounding the Pearl River Delta. Fine particulate matter was analyzed for chemical composition, regional variation, and meteorological impacts. On the Greenland Ice Sheet and in the Colorado Rocky Mountains, the carbonaceous fraction (organic and elemental carbon) of particulate matter was studied in the atmosphere and snow pack. Analyses included quantifying particulate chemical and optical properties, assessing atmospheric transport, and evaluating post-depositional processing of carbonaceous species in snow.
SYNTHETIC COPPER-CONTAINING PARTICLES ENHANCE ALLERGIC AIRWAY RESPONSES IN MICE
Respiratory morbidity and mortality associated with increases in ambient levels of particulate matter (PM) may be dependent on particle elemental composition. Particle-associated metals such as copper may catalyze formation of reactive oxygen species leading to inflammation and l...
Exposure to Air Pollution Enhances the Generation of Vascular Microparticles
Epidemiological studies associate exposure to ambient levels of particulate matter (PM) with cardiovascular morbidity and mortality. The biological mechanisms by which PM exposure induces cardiovascular effects remain to be elucidated. One important limitation is the lack of sens...
Air cleaning performance of a new environmentally controlled primary crusher operator booth.
Organiscak, J A; Cecala, A B; Zimmer, J A; Holen, B; Baregi, J R
2016-02-01
The National Institute for Occupational Safety and Health (NIOSH) cooperated with 3M Company in the design and testing of a new environmentally controlled primary crusher operator booth at the company's Wausau granite quarry near Wausau, WI. This quarry had an older crusher booth without a central heating, ventilation and air conditioning (HVAC) system, and without an air filtration and pressurization system. A new replacement operator booth was designed and installed by 3M based on design considerations from past NIOSH research on enclosed cab filtration systems. NIOSH conducted pre-testing of the old booth and post-testing of the new booth to assess the new filtration and pressurization system's effectiveness in controlling airborne dusts and particulates. The booth's dust and particulate control effectiveness is described by its protection factor, expressed as a ratio of the outside to inside concentrations measured during testing. Results indicate that the old booth provided negligible airborne respirable dust protection and low particulate protection from the outside environment. The newly installed booth provided average respirable dust protection factors from 2 to 25 over five shifts of dust sampling with occasional worker ingress and egress from the booth, allowing some unfiltered contaminants to enter the enclosure. Shorter-term particle count testing outside and inside the booth under near-steady-state conditions, with no workers entering or exiting the booth, resulted in protection factors from 35 to 127 on 0.3- to 1.0-μm respirable size particulates under various HVAC airflow operating conditions.
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
A test program to collect and analyze size-fractionated stack gas particulate samples for selected inorganic hazardous air pollutants (HAPs) was conducted . Specific goals of the program are (1) the collection of one-gram quantities of size-fractionated stack gas particulate matter for bulk (total) and surface chemical characterization, and (2) the determination of the relationship between particle size, bulk and surface (leachable) composition, and unit load. The information obtained from this program identifies the effects of unit load, particle size, and wet FGD system operation on the relative toxicological effects of exposure to particulate emissions. Field testing was conducted in twomore » phases. The Phase I field program was performed over the period of August 24 through September 20, 1992, at the Tennessee Valley Authority Widows Creek Unit 8 Power Station, located near Stevenson (Jackson County), Alabama, on the Tennessee River. Sampling activities for Phase II were conducted from September 11 through October 14, 1993. Widows Creek Unit 8 is a 575-megawatt plant that uses bituminous coal averaging 3.7% sulfur and 13% ash. Downstream of the boiler, a venture wet scrubbing system is used for control of both sulfur dioxide and particulate emissions. There is no electrostatic precipitator (ESP) in this system. This system is atypical and represents only about 5% of the US utility industry. However, this site was chosen for this study because of the lack of information available for this particulate emission control system.« less
Fumigation of Alcohol in a Light Duty Automotive Diesel Engine
NASA Technical Reports Server (NTRS)
Broukhiyan, E. M. H.; Lestz, S. S.
1981-01-01
A light-duty automotive Diesel engine was fumigated with methanol in amounts up to 35% and 50% of the total fuel energy respectively in order to determine the effect of alcohol fumigation on engine performance at various operating conditons. Engine fuel efficiency, emissions, smoke, and the occurrence of severe knock were the parameters used to evaluate performance. Raw exhaust particulate and its soluble organic extract were screened for biological activity using the Ames Salmonella typhimurium assay. Results are given for a test matrix made up of twelve steady-state operating conditions. For all conditions except the 1/4 rack (light load) condition, modest thermal efficiency gains were noted upon ethanol fumigation. Methanol showed the same increase at 3/4 and full rack (high load) conditions. However, engine roughness or the occurrence of severe knock limited the maximum amount of alcohol that could be fumigated. Brake specific nitrogen oxide concentrations were found to decrease for all ethanol conditions tested. Oxides of nitrogen emissions, on a volume basis, decreased for all alcohol conditions tested. Based on the limited particulate data analyzed, it appears that ethanol fumigation, like methanol fumigation, while lowering the mass of particulated emitted, does enhance the biological activity of that particulate.
Hargreaves, Andrew J; Vale, Peter; Whelan, Jonathan; Constantino, Carlos; Dotro, Gabriela; Campo, Pablo; Cartmell, Elise
2017-05-01
The distribution of Cu, Pb, Ni and Zn between particulate, colloidal and truly dissolved size fractions in wastewater from a trickling filter treatment plant was investigated. Samples of influent, primary effluent, humus effluent, final effluent and sludge holding tank returns were collected and separated into particulate (i.e. > 0.45 μm), colloidal (i.e. 1 kDa to 0.45 μm), and truly dissolved (i.e. < 1 kDa) fractions using membrane filters. In the influent, substantial proportions of Cu (60%), Pb (67%), and Zn (32%) were present in the particulate fraction which was removed in conjunction with suspended particles at the works in subsequent treatment stages. In final effluent, sizeable proportions of Cu (52%), Pb (32%), Ni (44%) and Zn (68%) were found within the colloidal size fraction. Calculated ratios of soluble metal to organic carbon suggest the metal to be adsorbed to or complexed with non-humic macromolecules typically found within the colloidal size range. These findings suggest that technologies capable of removing particles within the colloidal fraction have good potential to enhance metals removal from wastewater. Copyright © 2017 Elsevier Ltd. All rights reserved.
Code of Federal Regulations, 2013 CFR
2013-07-01
... Pollutants for Coke Ovens: Pushing, Quenching, and Battery Stacks Initial Compliance Requirements § 63.7326... coke oven battery subject to the emission limit for particulate matter from a control device applied to... process-weighted mass rate of particulate matter (lb/ton of coke), measured in accordance with the...
Code of Federal Regulations, 2014 CFR
2014-07-01
... Pollutants for Coke Ovens: Pushing, Quenching, and Battery Stacks Initial Compliance Requirements § 63.7326... coke oven battery subject to the emission limit for particulate matter from a control device applied to... process-weighted mass rate of particulate matter (lb/ton of coke), measured in accordance with the...
Code of Federal Regulations, 2011 CFR
2011-07-01
... Pollutants for Coke Ovens: Pushing, Quenching, and Battery Stacks Initial Compliance Requirements § 63.7326... coke oven battery subject to the emission limit for particulate matter from a control device applied to... process-weighted mass rate of particulate matter (lb/ton of coke), measured in accordance with the...
Code of Federal Regulations, 2010 CFR
2010-07-01
... Pollutants for Coke Ovens: Pushing, Quenching, and Battery Stacks Initial Compliance Requirements § 63.7326... coke oven battery subject to the emission limit for particulate matter from a control device applied to... process-weighted mass rate of particulate matter (lb/ton of coke), measured in accordance with the...
Code of Federal Regulations, 2012 CFR
2012-07-01
... Pollutants for Coke Ovens: Pushing, Quenching, and Battery Stacks Initial Compliance Requirements § 63.7326... coke oven battery subject to the emission limit for particulate matter from a control device applied to... process-weighted mass rate of particulate matter (lb/ton of coke), measured in accordance with the...
Particulate Matter Stack Emission Compliance Test Procedure for Fuel Burning Units.
ERIC Educational Resources Information Center
West Virginia Air Pollution Control Commission, Charleston.
This publication details the particulate matter emissions test procedure that is applicable for conducting compliance tests for fuel burning units required to be tested under Sub-section 7 of Regulation II (1972) as established by the state of West Virginia Air Pollution Control Commission. The testing procedure is divided into five parts:…
40 CFR 52.1638 - Bernalillo County particulate matter (PM10) Group II SIP commitments.
Code of Federal Regulations, 2011 CFR
2011-07-01
... (CONTINUED) New Mexico § 52.1638 Bernalillo County particulate matter (PM10) Group II SIP commitments. (a) On December 7, 1988, the Governor of New Mexico submitted a revision to the State Implementation Plan (SIP... SIPs. The City of Albuquerque and Bernalillo County Air Quality Control Board adopted this SIP revision...
40 CFR 52.1638 - Bernalillo County particulate matter (PM10) Group II SIP commitments.
Code of Federal Regulations, 2010 CFR
2010-07-01
... (CONTINUED) New Mexico § 52.1638 Bernalillo County particulate matter (PM10) Group II SIP commitments. (a) On December 7, 1988, the Governor of New Mexico submitted a revision to the State Implementation Plan (SIP... SIPs. The City of Albuquerque and Bernalillo County Air Quality Control Board adopted this SIP revision...
North Fork Clear Creek (NFCC) in Colorado, an acid-mine drainage (AMD) impacted stream, was chosen to examine the distribution of dissolved and particulate Cu, Fe, Mn, and Zn in the water column, with respect to seasonal hydrologic controls. NFCC is a high-gradient stream with d...
Epidemiological studies have shown that the presence of one air pollutant modifies the cardiovascular health effects of another while controlled exposure studies in humans have documented synergistic effects of co-exposure to ambient particulate matter (PM) and ozone (O3) on bloo...
40 CFR Table 2 to Subpart Fffff of... - Initial Compliance With Emission and Opacity Limits
Code of Federal Regulations, 2013 CFR
2013-07-01
... flow-weighted average concentration of particulate matter from one or more control devices applied to...). 4. Each discharge end at a new sinter plant a. The flow-weighted average concentration of... BOPF at a new or existing BOPF shop a. The average concentration of particulate matter from a primary...
40 CFR Table 2 to Subpart Fffff of... - Initial Compliance With Emission and Opacity Limits
Code of Federal Regulations, 2012 CFR
2012-07-01
... flow-weighted average concentration of particulate matter from one or more control devices applied to...). 4. Each discharge end at a new sinter plant a. The flow-weighted average concentration of... BOPF at a new or existing BOPF shop a. The average concentration of particulate matter from a primary...
40 CFR Table 2 to Subpart Fffff of... - Initial Compliance With Emission and Opacity Limits
Code of Federal Regulations, 2011 CFR
2011-07-01
... flow-weighted average concentration of particulate matter from one or more control devices applied to...). 4. Each discharge end at a new sinter plant a. The flow-weighted average concentration of... BOPF at a new or existing BOPF shop a. The average concentration of particulate matter from a primary...
40 CFR Table 2 to Subpart Fffff of... - Initial Compliance With Emission and Opacity Limits
Code of Federal Regulations, 2014 CFR
2014-07-01
... flow-weighted average concentration of particulate matter from one or more control devices applied to...). 4. Each discharge end at a new sinter plant a. The flow-weighted average concentration of... BOPF at a new or existing BOPF shop a. The average concentration of particulate matter from a primary...
Environmentally-friendly animal litter
Boxley, Chett; McKelvie, Jessica
2012-08-28
An animal litter composition including geopolymerized ash particulates having a network of repeating aluminum-silicon units is described herein. Generally, the animal litter is made from a quantity of a pozzolanic ash mixed with a sufficient quantity of water and an alkaline activator to initiate a geopolymerization reaction that forms geopolymerized ash. After the geopolymerized ash is formed, it is dried, broken into particulates, and sieved to a desired size. These geopolymerized ash particulates are used to make a non-clumping or clumping animal litter. Odor control is accomplished with the addition of a urease inhibitor, pH buffer, an odor eliminating agent, and/or fragrance.
NASA Astrophysics Data System (ADS)
Mukherjee, Devajyoti; Hyde, Robert; Mukherjee, Pritish; Srikanth, Hariharan; Witanachchi, Sarath
2012-03-01
Pb depletion in Pb(Zr0.52Ti0.48)O3 (PZT) thin films has remained as a major setback in the growth of defect-free PZT thin films by pulsed laser ablation techniques. At low excimer (KrF) laser fluences, the high volatility of Pb in PZT leads to non-congruent target ablation and, consequently, non-stoichiometric films, whereas, at high laser fluences, the inherent ejection of molten droplets from the target leads to particulate laden films, which is undesirable in heterostructure growth. To overcome these issues, a dual-laser ablation (PLDDL) process that combines an excimer (KrF) laser and CO2 laser pulses was used to grow epitaxial PZT films on SrTiO3 (100) and MgO (100) substrates. Intensified-charge-coupled-detector (ICCD) images and optical emission spectroscopy of the laser-ablated plumes in PLDDL revealed a broader angular expansion and enhanced excitation of the ablated species as compared to those for single-laser ablation (PLDSL). This led to the growth of particulate-free PZT films with higher Pb content, better crystallinity, and lower surface roughness as compared to those deposited using PLDSL. For FE measurements, PZT capacitors were fabricated in situ using the latticed-matched metallic oxide, La0.7Sr0.3MnO3, as the top and bottom electrodes. PZT films deposited using PLDDL exhibited enhanced polarization for all driving voltages as compared to those deposited using PLDSL. A highest remanent polarization (Pr) of ˜91 μC/cm2 and low coercive field of ˜40 kV/cm was recorded at 9 V driving voltage. Fatigue characterization revealed that PZT films deposited using PLDDL showed unchanging polarization, even after 109 switching cycles.
Nitrate-driven urban haze pollution during summertime over the North China Plain
NASA Astrophysics Data System (ADS)
Li, Haiyan; Zhang, Qiang; Zheng, Bo; Chen, Chunrong; Wu, Nana; Guo, Hongyu; Zhang, Yuxuan; Zheng, Yixuan; Li, Xin; He, Kebin
2018-04-01
Compared to the severe winter haze episodes in the North China Plain (NCP), haze pollution during summertime has drawn little public attention. In this study, we present the highly time-resolved chemical composition of submicron particles (PM1) measured in Beijing and Xinxiang in the NCP region during summertime to evaluate the driving factors of aerosol pollution. During the campaign periods (30 June to 27 July 2015, for Beijing and 8 to 25 June 2017, for Xinxiang), the average PM1 concentrations were 35.0 and 64.2 µg m-3 in Beijing and Xinxiang. Pollution episodes characterized with largely enhanced nitrate concentrations were observed at both sites. In contrast to the slightly decreased mass fractions of sulfate, semivolatile oxygenated organic aerosol (SV-OOA), and low-volatility oxygenated organic aerosol (LV-OOA) in PM1, nitrate displayed a significantly enhanced contribution with the aggravation of aerosol pollution, highlighting the importance of nitrate formation as the driving force of haze evolution in summer. Rapid nitrate production mainly occurred after midnight, with a higher formation rate than that of sulfate, SV-OOA, or LV-OOA. Based on observation measurements and thermodynamic modeling, high ammonia emissions in the NCP region favored the high nitrate production in summer. Nighttime nitrate formation through heterogeneous hydrolysis of dinitrogen pentoxide (N2O5) enhanced with the development of haze pollution. In addition, air masses from surrounding polluted areas during haze episodes led to more nitrate production. Finally, atmospheric particulate nitrate data acquired by mass spectrometric techniques from various field campaigns in Asia, Europe, and North America uncovered a higher concentration and higher fraction of nitrate present in China. Although measurements in Beijing during different years demonstrate a decline in the nitrate concentration in recent years, the nitrate contribution in PM1 still remains high. To effectively alleviate particulate matter pollution in summer, our results suggest an urgent need to initiate ammonia emission control measures and further reduce nitrogen oxide emissions over the NCP region.
Glacial cycles influence marine methane hydrate formation
Malinverno, A.; Cook, A. E.; Daigle, H.; ...
2018-01-12
Methane hydrates in fine-grained continental slope sediments often occupy isolated depth intervals surrounded by hydrate-free sediments. As they are not connected to deep gas sources, these hydrate deposits have been interpreted as sourced by in situ microbial methane. We investigate here the hypothesis that these isolated hydrate accumulations form preferentially in sediments deposited during Pleistocene glacial lowstands that contain relatively large amounts of labile particulate organic carbon, leading to enhanced microbial methanogenesis. To test this hypothesis, we apply an advection-diffusion-reaction model with a time-dependent organic carbon deposition controlled by glacioeustatic sea level variations. In the model, hydrate forms in sedimentsmore » with greater organic carbon content deposited during the penultimate glacial cycle (~120-240 ka). As a result, the model predictions match hydrate-bearing intervals detected in three sites drilled on the northern Gulf of Mexico continental slope, supporting the hypothesis of hydrate formation driven by enhanced organic carbon burial during glacial lowstands.« less
Glacial cycles influence marine methane hydrate formation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Malinverno, A.; Cook, A. E.; Daigle, H.
Methane hydrates in fine-grained continental slope sediments often occupy isolated depth intervals surrounded by hydrate-free sediments. As they are not connected to deep gas sources, these hydrate deposits have been interpreted as sourced by in situ microbial methane. We investigate here the hypothesis that these isolated hydrate accumulations form preferentially in sediments deposited during Pleistocene glacial lowstands that contain relatively large amounts of labile particulate organic carbon, leading to enhanced microbial methanogenesis. To test this hypothesis, we apply an advection-diffusion-reaction model with a time-dependent organic carbon deposition controlled by glacioeustatic sea level variations. In the model, hydrate forms in sedimentsmore » with greater organic carbon content deposited during the penultimate glacial cycle (~120-240 ka). As a result, the model predictions match hydrate-bearing intervals detected in three sites drilled on the northern Gulf of Mexico continental slope, supporting the hypothesis of hydrate formation driven by enhanced organic carbon burial during glacial lowstands.« less
Air Sensor Kit Performance Testing and Pollutant Mapping Supports Community Air Monitoring Project
EPA is collaborating on a research project with the South Coast Air Quality Management District in Diamond Bar, Calif. to gain an enhanced understanding of fine particulate matter (PM2.5) and ozone concentrations across the study area.
Enhanced photophysics of conjugated polymers
Chen, Liaohai [Darien, IL
2007-06-12
A particulate fluorescent conjugated polymer surfactant complex and method of making and using same. The particles are between about 15 and about 50 nm and when formed from a lipsome surfactant have a charge density similar to DNA and are strongly absorbed by cancer cells.
VASCULAR RESPONSE TO TRAFFIC-DERIVED INHALATION IN HUMANS
By coordinating closely with Center Projects 1-3, we will determine whether specific aspects of traffic-derived exposure (primary vs. secondary organics, particulate vs. gases, spark-ignition vs. diesel engine vs. a mixture) enhance the human vascular response to pollutants. W...
McNeal, E T; Daly, J W
1986-01-01
Batrachotoxinin-A [(3)H]benzoate ([(3)H]BTX-B) binds specifically and with high affinity (K(D) 48 nM) to sites (B(max) 2.1 pmol/mg protein) associated with voltage-dependent sodium channels in rodent brain vesicular preparations. High affinity binding requires the presence of scorpion (Leiurus) venom and a membrane potential. Local anesthetics antagonize the binding. Nonspecific binding is defined in the presence of veratridine. In particulate preparations from electroplax of the eel Electrophorus electricus, [(3)H]BTX-B binds with a K(D) of about 140 nM and a B(max) of 2.5 pmol/mg protein in the presence of scorpion venom. Higher concentrations of scorpion venom are required to enhance binding in Electrophorus preparations than in brain preparations. Local anesthetics antagonize binding in Electrophorus preparations with potencies similar to those in brain preparations. Veratridine and batrachotoxin are less potent in blocking binding in Electrophorus than in brain preparations. It appears likely that binding in Electrophorus preparations is primarily to membrane fragments rather than vesicular entities as in brain. Binding of [(3)H]BTX-B to particulate preparations from electroplax of the ray Torpedo californica and the catfish Malapterurus electricus is mainly nonspecific. Scorpion venom does not enhance total binding and local anesthetics are not effective in antagonizing binding.
Wang, Ruwei; Liu, Guijian; Sun, Ruoyu; Yousaf, Balal; Wang, Jizhong; Liu, Rongqiong; Zhang, Hong
2018-07-01
The partitioning behavior of polycyclic aromatic hydrocarbons (PAHs) between gaseous and particulate phases from coal-fired power plants (CFPPs) is critically important to predict PAH removal by dust control devices. In this study, 16 US-EPA priority PAHs in gaseous and size-segregated particulate phases at the inlet and outlet of the fabric filter unit (FFs) of a circulating fluidized bed (CFB) boiler were analyzed. The partitioning mechanisms of PAHs between gaseous and particulate phases and in particles of different size classes were investigated. We found that the removal efficiencies of PAHs are 45.59% and 70.67-89.06% for gaseous and particulate phases, respectively. The gaseous phase mainly contains low molecular weight (LMW) PAHs (2- and 3-ring PAHs), which is quite different from the particulate phase that mainly contains medium and high molecular weight (MMW and HMW) PAHs (4- to 6-ring PAHs). The fractions of LMW PAHs show a declining trend with the decrease of particle size. The gas-particle partitioning of PAHs is primarily controlled by organic carbon absorption, in addition, it has a clear dependence on the particle sizes. Plot of log (TPAH/PM) against logD p shows that all slope values were below -1, suggesting that PAHs were mainly adsorbed to particulates. The adsorption effect of PAHs in size-segregated PMs for HMW PAHs is more evident than LMW PAHs. The particle size distributions (PSDs) of individual PAHs show that most of PAHs exhibit bi-model structures, with one mode peaking in the accumulation size range (2.1-1.1 μm) and another mode peaking in coarse size range (5.8-4.7 μm). The intensities of these two peaks vary in function of ring number of PAHs, which is likely attributed to Kelvin effect that the less volatile HMW PAH species preferentially condense onto the finer particulates. The emission factor of PAHs was calculated as 3.53 mg/kg of coal burned, with overall mean EF PAH of 0.55 and 2.98 mg/kg for gaseous and particulate phase, respectively. Moreover, the average emission amount of PAHs for the investigated CFPP was 1016.6 g/day and 371073.6 g/y, respectively. Copyright © 2018 Elsevier Ltd. All rights reserved.
Ash reduction system using electrically heated particulate matter filter
Gonze, Eugene V [Pinckney, MI; Paratore, Jr., Michael J; He, Yongsheng [Sterling Heights, MI
2011-08-16
A control system for reducing ash comprises a temperature estimator module that estimates a temperature of an electrically heated particulate matter (PM) filter. A temperature and position estimator module estimates a position and temperature of an oxidation wave within the electrically heated PM filter. An ash reduction control module adjusts at least one of exhaust flow, fuel and oxygen levels in the electrically heated PM filter to adjust a position of the oxidation wave within the electrically heated PM filter based on the oxidation wave temperature and position.
A laboratory comparison of evacuation devices on aerosol reduction.
Jacks, Mary E
2002-01-01
Aerosols are defined as airborne particles that range in size from 0.5 to 10 microns (micron). They are produced during ultrasonic instrumentation, but they can be reduced. Irrigant solutions, which produce the therapeutic effects of lavage, also combine with blood, saliva, and bacteria to produce potentially harmful airborne particulates. The American Dental Association (ADA) and the Centers for Disease Control and Prevention (CDC) recommend utilization of high volume evacuation, rubber dam, and patient positioning for aerosol control. But for the non-assisted dental hygienist, these recommendations are difficult to implement. This study was designed to compare the concentration of airborne particulates from ultrasonic scaling, utilizing three different methods of evacuation. In a laboratory setting, ultrasonic airborne particulates were generated utilizing a 25,000 cps magnetostrictive ultrasonic scaling instrument. Three evacuation devises were compared for effectiveness: a standard saliva ejector intraorally positioned; and two extraorally positioned, hands-free high-volume evacuation (HFHVE) techniques. One of these devices had a standard attachment, and, the other had a funnel-shaped attachment. Measurement of airborne particles was performed with a DataRAM Real-Time Aerosol Monitor. This study (N = 21) found a significant reduction in the number of airborne particulates with either form of extraoral HFHVE attachment in place. Standard attachments and funnel-shaped attachments to HFHVE resulted in reduction of particulates by 90.8% and 89.7%, respectively, when compared to the intraorally positioned standard saliva ejector. Utilizing either form of HFHVE during ultrasonic instrumentation significantly reduced the number of aerosolized particulates that reached the breathing space of the client and clinician. This lends support for the ADA and CDC recommendation that HVE be used during aerosol producing procedures. Currently, no preventive measure is 100% effective; therefore, clinicians are encouraged to use additional methods to minimize the number of airborne particulates produced during intraoral instrumentation.
Toxecon Retrofit for Mercury and Mulit-Pollutant Control on Three 90-MW Coal-Fired Boilers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Steven Derenne; Robin Stewart
2009-09-30
This U.S. Department of Energy (DOE) Clean Coal Power Initiative (CCPI) project was based on a cooperative agreement between We Energies and the DOE Office of Fossil Energy's National Energy Technology Laboratory (NETL) to design, install, evaluate, and demonstrate the EPRI-patented TOXECON{trademark} air pollution control process. Project partners included Cummins & Barnard, ADA-ES, and the Electric Power Research Institute (EPRI). The primary goal of this project was to reduce mercury emissions from three 90-MW units that burn Powder River Basin coal at the We Energies Presque Isle Power Plant in Marquette, Michigan. Additional goals were to reduce nitrogen oxide (NO{submore » x}), sulfur dioxide (SO{sub 2}), and particulate matter emissions; allow reuse and sale of fly ash; advance commercialization of the technology; demonstrate a reliable mercury continuous emission monitor (CEM) suitable for use at power plants; and demonstrate recovery of mercury from the sorbent. Mercury was controlled by injection of activated carbon upstream of the TOXECON{trademark} baghouse, which achieved more than 90% removal on average over a 44-month period. During a two-week test involving trona injection, SO{sub 2} emissions were reduced by 70%, although no coincident removal of NOx was achieved. The TOXECON{trademark} baghouse also provided enhanced particulate control, particularly during startup of the boilers. On this project, mercury CEMs were developed and tested in collaboration with Thermo Fisher Scientific, resulting in a reliable CEM that could be used in the power plant environment and that could measure mercury as low as 0.1 {micro}g/m{sup 3}. Sorbents were injected downstream of the primary particulate collection device, allowing for continued sale and beneficial use of captured fly ash. Two methods for recovering mercury using thermal desorption on the TOXECON{trademark} PAC/ash mixture were successfully tested during this program. Two methods for using the TOXECON{trademark} PAC/ash mixture in structural concrete were also successfully developed and tested. This project demonstrated a significant reduction in the rate of emissions from Presque Isle Units 7, 8, and 9, and substantial progress toward establishing the design criteria for one of the most promising mercury control retrofit technologies currently available. The Levelized Cost for 90% mercury removal at this site was calculated at $77,031 per pound of mercury removed with a capital cost of $63,189 per pound of mercury removed. Mercury removal at the Presque Isle Power Plant averages approximately 97 pounds per year.« less
Yokota, Satoshi; Oshio, Shigeru; Moriya, Nozomu; Takeda, Ken
2016-01-01
Diesel exhaust particles are a major component of ambient particulate matter, and concern about the health effects of exposure to ambient particulate matter is growing. Previously, we found that in utero exposure to diesel exhaust affected locomotor activity and motor coordination, but there are also indications that such exposure may contribute to increased aggression in offspring. Therefore, the aim of the present study was to test the effects of prenatal diesel exhaust exposure on social isolation-induced territorial aggression. Pregnant mice were exposed to low concentrations of diesel exhaust (DE; mass concentration of 90 μg/m3: DE group: n = 15) or clean air (control group: n = 15) for 8 h/day during gestation. Basal locomotion of male offspring was measured at 10 weeks of age. Thereafter, male offspring were individually housed for 2 weeks and subsequently assessed for aggression using the resident−intruder test at 12 weeks of age, and blood and brain tissue were collected from the male offspring on the following day for measuring serum testosterone levels and neurochemical analysis. There were no significant differences in locomotion between control and DE-exposed mice. However, DE-exposed mice showed significantly greater social isolation-induced territorial aggressive behavior than control mice. Additionally, socially-isolated DE-exposed mice expressed significantly higher concentrations of serum testosterone levels than control mice. Neurochemical analysis revealed that dopamine levels in the prefrontal cortex and nucleus accumbens were higher in socially isolated DE-exposed mice. Serotonin levels in the nucleus accumbens, amygdala, and hypothalamus were also lower in the socially isolated DE-exposed mice than in control mice. Thus, even at low doses, prenatal exposure to DE increased aggression and serum testosterone levels, and caused neurochemical changes in male socially isolated mice. These results may have serious implications for pregnant women living in regions with high levels of traffic-related air pollution. PMID:26919122
NASA Astrophysics Data System (ADS)
Fraterrigo, J.; Ream, K.; Knoepp, J.
2017-12-01
Forest insects and pathogens (FIPs) can cause uncertain changes in forest carbon balance, potentially influencing global atmospheric carbon dioxide (CO2) concentrations. We quantified the effects of hemlock (Tsuga canadensis L. Carr.) mortality on soil carbon fluxes and pools for a decade following either girdling or natural infestation by hemlock woolly adelgid (HWA; Adelges tsugae) to improve mechanistic understanding of soil carbon cycling response to FIPs. Although soil respiration (Rsoil) was similar among reference plots and plots with hemlock mortality, both girdled and HWA-infested plots had greater activities of β-glucosidase, a cellulose-hydrolyzing extracellular enzyme, and decreased O-horizon mass and fine root biomass from 2005 to 2013. During this period, total mineral soil carbon accumulated at a higher rate in disturbed plots than in reference plots in both the surface (0-10 cm) and subsurface (10-30 cm); increases were predominantly in the mineral-associated fraction of the soil organic matter. In contrast, particulate organic matter carbon accrued slowly in surface soils and declined in the subsurface of girdled plots. δ13C values of this fraction demonstrate that particulate organic matter carbon in the surface soil has become more microbially processed over time, suggesting enhanced decomposition of organic matter in this pool. Together, these findings indicate that hemlock mortality and subsequent forest regrowth has led to enhanced soil carbon stabilization in southern Appalachian forests through the translocation of carbon from detritus and particulate soil organic matter pools to the mineral-associated organic matter pool. These findings have implications for ecosystem management and modeling, demonstrating that forests may tolerate moderate disturbance without diminishing soil carbon storage when there is a compensatory growth response by non-host trees.
Emmerechts, J; Alfaro-Moreno, E; Vanaudenaerde, B M; Nemery, B; Hoylaerts, M F
2010-12-01
Epidemiological findings suggest an association between exposure to particulate matter (PM) and venous thrombo-embolism. To investigate arterial vs. venous thrombosis, inflammation and coagulation in mice, (sub)acutely exposed to two types of PM. Various doses (25, 100 and 200 μg per animal) of urban particulate matter (UPM) or diesel exhaust particles (DEP) were intratracheally (i.t.) instilled in C57Bl6/n mice and several endpoints measured at 4, 10 and 24 h. Mice were also repeatedly exposed to 100 μg per animal on three consecutive days with endpoints measured 24 h after the last instillation. Exposure to 200 μg per mouse UPM enhanced arterial thrombosis, but neither UPM nor DEP significantly enhanced venous thrombosis. Both types of PM induced dose-dependent increases in broncho-alveolar lavage fluid (BALF) total cell numbers (mainly neutrophils) and cytokines (IL-6, KC, MCP-1, RANTES, MIP-1α), with peaks at 4 h and overall higher values for UPM than for DEP. Systemic inflammation was limited to increased serum IL-6 levels, 4 h after UPM. Both types of PM induced similar and dose-dependent but modest increases in factor (F)VII, FVIII and fibrinogen. Three repeated instillations did not or only modestly enhance the proinflammatory and procoagulant status. Compared with DEP, UPM induced more pronounced pulmonary inflammation, but both particle types triggered similar and mild short-term systemic effects. Hence, acute exposure to PM triggers activation of primary hemostasis in the mouse, but no substantial secondary hemostasis activation, resulting in arterial but not venous thrombogenicity. © 2010 International Society on Thrombosis and Haemostasis.
Aspects of Microparticle Utilization for Potentiation of Novel Vaccines: Promises and Risks
NASA Astrophysics Data System (ADS)
Ilyinskii, P.
Many recombinant vaccines against novel (HIV, HCV) or ever-changing (influenza) infectious agents require the presence of adjuvants/delivery vehicles to induce strong immune responses. The necessity of their improvement led to the major effort towards development of vaccine delivery systems that are generally particulate (e.g., nano- and microparticles) and have comparable dimensions to the pathogens (viruses or bacteria). The mode of action of these adjuvants is not fully understood but implies the stimulation of the innate or antigen-specific immune responses, and/or the increase of antigen uptake or processing by antigen-presenting cells (APC). Moreover, enhancement of adjuvant activity through the use of micro- and nanoparticulate delivery systems often resulted from the synergistic effects producing immune responses stronger than those elicited by the adjuvant or delivery system alone. Among particulate adjuvants, biodegradable micro- and nanoparticles of poly(D,L-lactide-co-glycoside) (PLGA) or poly(D,L-lactide) (PLA) have been reported to enhance both humoral and cellular immune responses against an encapsulated protein antigen. Cationic and anionic polylactide co-glycolide (PLG) microparticles have been successfully used to adsorb a variety of agents, which include plasmid DNA, recombinant proteins and adjuvant active oligonucleotides and are also currently tested in several vaccine applications. Another approach envisions specific targeting of APC, especially peripheral DC and exploitation of particulate systems that are small enough for lymphatic uptake (polystyrene nanobeads). Micro- and nanoparticles offer the possibility of enhancement of their uptake by appropriate cells through manipulation of their surface properties. Still, questions regarding toxicity and molecular interaction between micro- and nano-particles and immune cells, tissues and whole organisms remain to be addressed. These risks and other possible side effects should be assessed in detail especially if mass-production and massive administration of such preparations is to be considered.
NASA Astrophysics Data System (ADS)
Fushimi, Akihiro; Saitoh, Katsumi; Hayashi, Kentaro; Ono, Keisuke; Fujitani, Yuji; Villalobos, Ana M.; Shelton, Brandon R.; Takami, Akinori; Tanabe, Kiyoshi; Schauer, James J.
2017-08-01
Open burning of crop residue is a major source of atmospheric fine particle emissions. We burned crop residues (rice straws, barley straws, wheat straws, and rice husks produced in Japan) in an outdoor chamber and measured particle mass, composition (elemental carbon: EC, organic carbon: OC, ions, elements, and organic species), and oxidative potential in the exhausts. The fine particulate emission factors from the literature were within the range of our values for rice straws but were 1.4-1.9 and 0.34-0.44 times higher than our measured values for barley straw and wheat straw, respectively. For rice husks and wheat straws, which typically lead to combustion conditions that are relatively mild, the EC content of the particles was less than 5%. Levoglucosan seems more suitable as a biomass burning marker than K+, since levoglucosan/OC ratios were more stable than K+/particulate mass ratios among crop species. Stigmasterol and β-sitosterol could also be used as markers of biomass burning with levoglucosan or instead of levoglucosan. Correlation analysis between chemical composition and combustion condition suggests that hot or flaming combustions enhance EC, K+, Cl- and polycyclic aromatic hydrocarbons emissions, while low-temperature or smoldering combustions enhance levoglucosan and water-soluble organic carbon emissions. Oxidative potential, measured with macrophage-based reactive oxygen species (ROS) assay and dithiothreitol (DTT) assay, of open burning fine particles per particulate mass as well as fine particulate emission factors were the highest for wheat straws and second highest for rice husks and rice straws. Oxidative potential per particulate mass was in the lower range of vehicle exhaust and atmosphere. These results suggest that the contribution of open burning is relatively small to the oxidative potential of atmospheric particles. In addition, oxidative potential (both ROS and DTT activities) correlated well with water-insoluble organic species, suggesting that OC components, especially water-insoluble OC components emitted under non-flaming combustion, have a major impact on oxidative potential.
Baskaran, M.; Swarzenski, P.W.
2007-01-01
Historically, Tampa Bay has been impacted heavily by a wide range of anthropogenic perturbations that may include, agricultural-, shipping-, phosphate mining/distribution-related activities, as well as a burgeoning coastal population. Due to the presence of U-rich underlying sediments, elevated activities of U- and Th-series daughter products may be naturally released into this system. This region is also known for summer thunderstorms and corresponding increases in precipitation and surface water runoff. Only limited work has been conducted on the partitioning of particle-reactive radionuclides (such as 7Be, 210Pb, and 234Th) in such a dynamic coastal system. We investigated both the removal residence time and partitioning of these radionuclides between filter-retained particulate matter (≥ 0.5 μm) and the filtrate ( Our results indicate that the partitioning of 7Be, 210Pb, and 234Th between filtrate and filter-retained phase is controlled foremost by enhanced bottom resuspension events during summer thunderstorms. As a consequence, no significant relationship exists between the distribution coefficients (Kd values) of these isotopes and the concentration of suspended particulate matter (SPM). Relatively faster recycling rates of atmospheric water vapor derived from the ocean results in lower atmospheric depositional fluxes of 210Pb to the study site than predicted. The relationship between 7Be and 210Pb in bulk (wet + dry) deposition is compared to their respective water column activities. The residence times of particulate and dissolved 234Th, 7Be and 210Pb, as well the distribution coefficients of these radionuclides, are then compared to values reported in other coastal systems.
NASA Astrophysics Data System (ADS)
Büks, Frederick; Kaupenjohann, Martin
2016-10-01
The stability of soil aggregates against shearing and compressive forces as well as water-caused dispersion is an integral marker of soil quality. High stability results in less compaction and erosion and has been linked to enhanced water retention, dynamic water transport and aeration regimes, increased rooting depth, and protection of soil organic matter (SOM) against microbial degradation. In turn, particulate organic matter is supposed to support soil aggregate stabilization. For decades the importance of biofilm extracellular polymeric substances (EPSs) regarding particulate organic matter (POM) occlusion and aggregate stability has been canonical because of its distribution, geometric structure and ability to link primary particles. However, experimental proof is still missing. This lack is mainly due to methodological reasons. Thus, the objective of this work is to develop a method of enzymatic biofilm detachment for studying the effects of EPSs on POM occlusion. The method combines an enzymatic pre-treatment with different activities of α-glucosidase, β-galactosidase, DNAse and lipase with a subsequent sequential ultrasonic treatment for disaggregation and density fractionation of soils. POM releases of treated samples were compared to an enzyme-free control. To test the efficacy of biofilm detachment the ratio of bacterial DNA from suspended cells and the remaining biofilm after enzymatic treatment were measured by quantitative real-time PCR. Although the enzyme treatment was not sufficient for total biofilm removal, our results indicate that EPSs may attach POM within soil aggregates. The tendency to additional POM release with increased application of enzymes was attributed to a slight loss in aggregate stability. This suggests that an effect of agricultural practices on soil microbial populations could influence POM occlusion/aggregate stability and thereby carbon cycle/soil quality.
When I first became involved in particulate control research, there were always a few guys with gray hair,.white beards, and big cigars nodding and mumbling, "We knew that 20 years ago." Now, 30 years later, the only things that have changed are the cigars are gone, and I'm one o...
Liu, Wei; Yang, Xiang-Liang; Ho, W S Winston
2011-01-01
Much attention has in recent years been paid to fine applications of drug delivery systems, such as multiple emulsions, micro/nano solid lipid and polymer particles (spheres or capsules). Precise control of particle size and size distribution is especially important in such fine applications. Membrane emulsification can be used to prepare uniform-sized multiple emulsions and micro/nano particulates for drug delivery. It is a promising technique because of the better control of size and size distribution, the mildness of the process, the low energy consumption, easy operation and simple equipment, and amendable for large scale production. This review describes the state of the art of membrane emulsification in the preparation of monodisperse multiple emulsions and micro/nano particulates for drug delivery in recent years. The principles, influence of process parameters, advantages and disadvantages, and applications in preparing different types of drug delivery systems are reviewed. It can be concluded that the membrane emulsification technique in preparing emulsion/particulate products for drug delivery will further expand in the near future in conjunction with more basic investigations on this technique. Copyright © 2010 Wiley-Liss, Inc. and the American Pharmacists Association
Fine urban and precursor emissions control for diesel urban transit buses.
Lanni, Thomas
2003-01-01
Particulate emission from diesel engines is one of the most important pollutants in urban areas. As a result, particulate emission control from urban bus diesel engines using particle filter technology is being evaluated at several locations in the US. A project entitled "Clean Diesel Air Quality Demonstration Program" has been initiated by the New York City Metropolitan Transit Authority (MTA) under the supervision of New York State Department of Environmental Conservation and with active participation from Johnson Matthey, Corning, Equilon, Environment Canada and RAD Energy. Under this program, several MTA transit buses with DDC Series 50 engines were equipped with Continuously Regenerating Technology (CRTTM) particulate filter systems and have been operated with ultra low sulfur diesel (<30 ppm S) in transit service in Manhattan since February 2000. These buses were evaluated over a 9-month period for durability and maintainability of the particulate filter. In addition, an extensive emissions testing program was carried out using transient cycles on a chassis dynamometer to evaluate the emissions reductions obtained with the particle filter. In this paper, the emissions testing data from the Clean Diesel Air Quality Demonstration Program are discussed in detail.
School Environmental Intervention to Reduce Particulate Pollutant Exposures for Children with Asthma
Jhun, Iny; Gaffin, Jonathan M.; Coull, Brent A.; Huffaker, Michelle F.; Petty, Carter R.; Sheehan, William J.; Baxi, Sachin N.; Lai, Peggy S.; Kang, Choong-Min; Wolfson, Jack M.; Gold, Diane R.; Koutrakis, Petros; Phipatanakul, Wanda
2016-01-01
Background Home-based interventions to improve indoor air quality have demonstrated benefits for asthma morbidity, yet little is known about the effect of environmental interventions in the school setting. Objective We piloted the feasibility and effectiveness of a classroom-based air cleaner intervention to reduce particulate pollutants in classrooms of children with asthma. Methods In this pilot randomized controlled trial, we assessed the effect of air cleaners on indoor air particulate pollutant concentrations in 18 classrooms (9 control, 9 intervention) in 3 urban elementary schools. We enrolled 25 asthmatic children (13 control, 12 intervention) aged 6–10 years old. Classroom air pollutant measurements and spirometry were completed once prior to and twice after randomization. Asthma symptoms were surveyed every 3 months. Results Baseline classroom levels of fine particulate matter (PM2.5) and black carbon (BC) were 6.3 μg/m3 and 0.41 μg/m3, respectively. When comparing the intervention to the control group, classroom PM2.5 levels were reduced by 49% and 42%, and BC levels were reduced by 58% and 55% in the first and second follow-up periods, respectively (p < 0.05 for all comparisons). When comparing the children randomized to intervention and control classrooms, there was a modest improvement in peak flow, but no significant changes in forced expiratory volume in 1 second (FEV1) and asthma symptoms. Conclusion In this pilot study, a classroom-based air cleaner intervention led to significant reductions in PM2.5 and BC. Future large-scale studies should comprehensively evaluate the effect of school-based environmental interventions on pediatric asthma morbidity. PMID:27641483
Oceanic biogeochemical controls on global dynamics of persistent organic pollutants.
Dachs, Jordi; Lohmann, Rainer; Ockenden, Wendy A; Méjanelle, Laurence; Eisenreich, Steven J; Jones, Kevin C
2002-10-15
Understanding and quantifying the global dynamics and sinks of persistent organic pollutants (POPs) is important to assess their environmental impact and fate. Air-surface exchange processes, where temperature plays a central role in controlling volatilization and deposition, are of key importance in controlling global POP dynamics. The present study is an assessment of the role of oceanic biogeochemical processes, notably phytoplankton uptake and vertical fluxes of particles, on the global dynamics of POPs. Field measurements of atmospheric polychlorinated biphenyls (PCBs), polychlorinated dibenzodioxins (PCDDs), and furans (PCDFs) are combined with remote sensing estimations of oceanic temperature, wind speed, and chlorophyll, to model the interactions between air-water exchange, phytoplankton uptake, and export of organic matter and POPs out of the mixed surface ocean layer. Deposition is enhanced in the mid-high latitudes and is driven by sinking marine particulate matter, rather than by a cold condensation effect. However, the relative contribution of the biological pump is a function of the physical-chemical properties of POPs. It is concluded that oceanic biogeochemical processes play a critical role in controlling the global dynamics and the ultimate sink of POPs.
NASA Astrophysics Data System (ADS)
Kabrein, H.; Hariri, A.; Leman, A. M.; Noraini, N. M. R.; Yusof, M. Z. M.; Afandi, A.
2017-09-01
Heating ventilation and air conditioning system (HVAC) is very important for offices building and human health. The combining filter method was used to reduce the air pollution indoor such as that particulate matter and gases pollution that affected in health and productivity. Using particle filters in industrial HVAC systems (factories and manufacturing process) does not enough to remove all the indoor pollution. The main objective of this study is to investigate the impact of combination filters for particle and gases removal efficiency. The combining method is by using two filters (particulate filter pre-filter and carbon filter) to reduce particle matter and gases respectively. The purpose of this study is to use minimum efficiency reporting value (MERV filter) rating 13 and activated carbon filter (ACF) to remove indoor air pollution and controlling the air change rate to enhance the air quality and energy saving. It was concluded that the combination filter showed good removal efficiency of particle up to 90.76% and 89.25% for PM10 and PM2.5 respectively. The pressure drop across the filters was small compared with the high-efficiency filters. The filtration efficiency of combination filters after three months’ was better than efficiency by the new MERV filter alone.
Sun, Juan; Zheng, Xilai
2009-10-01
It has been acknowledged that following an oil spill in coastal areas where suspended particulate matter (SPM) is rich, aggregation between oil and SPM can be naturally formed. This kind of aggregation product is termed as oil-SPM aggregates (OSAs). Because OSAs are not as sticky to the shorelines as crude oil and the oil-water contact area is greatly increased due to the formation of OSAs, both oil dispersion into the water body and oil biodegration would be significantly enhanced. In this review article, the authors (1) describe in detail the mechanism of OSA formation and controlling parameters which can influence OSA formation (the parameters discussed include the oil nature and properties, sediment types and concentrations, and the environmental factors such as salinity, temperature and mixing energy); (2) briefly review qualitative and quantitative methods used for characterization of OSA formation (two main methods used for the OSA characterization are the UV epi-fluorescence microscopy and gas chromatography equipped with flame ionization detector (GC-FID); (3) elucidate the applications of OSA formation in oil spill response strategies including natural attenuation, sediment relocation, and sediment mixing; and (4) discuss research needs in the future which would further improve our understanding of OSA formation and move towards the development of adequate oil behaviour models.
Joad, Jesse P; Sekizawa, Shin-ichi; Chen, Chao-Yin; Bonham, Ann C
2007-01-01
Epidemiological studies have shown that exposure to air pollution is associated with respiratory symptoms and decreases in lung function. This paper reviews recent literature showing that exposure to particulate matter, irritant gases, environmental tobacco smoke (ETS), mixed pollutants, and molds is associated with an increase in cough and wheeze. Some pollutants, like particulate matter and mixed pollutants, appear to increase cough at least as much as wheeze. Others, like irritant gases, appear to increase wheeze more than cough. For ETS, exposure during childhood is associated with cough and wheeze in adulthood, suggesting that the pollutant permanently alters some important aspect of the lungs, immune system or nervous system. We have shown in animal studies that pollutants change the neural control of airways and cough. Second hand smoke (SHS) exposure lengthened stimulated apnoea, increased the number of stimulated coughs, and augmented the degree of stimulated bronchoconstriction. The mechanisms included enhanced reactivity of the peripheral sensory neurones and second-order neurones in the nucleus tractus solitarius (NTS). NTS effects were due to a substance P mechanism at least in part. Ozone and allergen increased the intrinsic excitability of second-order neurones in the NTS. The animal studies suggest that the cough and wheeze experienced by humans exposed to pollutants may involve plasticity in the nervous system.
NASA Astrophysics Data System (ADS)
Wu, Ying; Liu, Zongguang; Hu, Jun; Zhu, Zhuoyi; Liu, Sumei; Zhang, Jing
2016-02-01
Total suspended matter (TSM) was collected in the Changjiang Estuary and adjacent areas of the East China Sea in July, August, and November 2011, to study the composition and fate of particulate organic nitrogen (PON) during an August typhoon event and bottom trawling activities. Concentrations of particulate organic carbon (POC), particulate nitrogen (PN), and hydrolyzable particulate amino acids (PAA, D- and L-enantiomers) were higher during July and August than during November; however, D-arginine and alanine levels were significantly higher in November. Seasonal trends in the composition of PAAs indicate that in situ production is a key factor in their temporal distribution. No significant increase in TSM or decrease in labile organic matter was observed during the transit period following a typhoon event in August. In contrast, higher primary production was observed at this time as a result of the penetration of Changjiang Diluted Water caused by the typhoon event. Trawling effects were studied by comparing the calm season (July) with the bottom-trawling period (November) at similar sampling sites. The effect of trawling on the composition of bottom organic matter was studied by comparing D-amino acids concentrations and C/N ratios in the calm season (July) with the bottom-trawling period (November). A substantial contribution of microbial organic matter during the November cruise was indicated by a decrease in glutamic acid, an increase in TSM and D-alanine, and a lower carbon/nitrogen (C/N) ratio. In shallow coastal regions, anthropogenic activities (bottom trawling) may enhance the transfer of low-nutritional-value particulate organic matter into the benthic food chain.
The geocentric particulate distribution: Cometary, asteroidal, or space debris?
NASA Technical Reports Server (NTRS)
Mcdonnell, J. A. M.; Ratcliff, P. R.
1992-01-01
Definition of the Low Earth Orbit (LEO) particulate environment has been refined considerably with the analysis of data from NASA's Long Duration Exposure Facility (LDEF). Measurements of the impact rates from particulates ranging from sub-micron to millimetres in dimension and, especially, information on their directionality has permitted new scrunity of the sources of the particulates. Modelling of the dynamics of both bound (Earth orbital) and unbound (hyperbolic interplanetary) particulates intercepting LDEF's faces leads to the conclusion that the source is dominantly interplanetary for particle dimensions of greater than some 5 microns diameter; however the anisotropy below this dimension demands lower velocities and is compatible with an orbital component. Characteristics of the LDEF interplanetary component are compatible with familiar meteoroid sources and deep space measurements. Understanding of the orbital component which exceeds the interplanetary flux by a factor of 4 is less clear; although the very small particulates in orbit have been associated with space debris (Lawrance and Brownlee, 1986) this data conflicts with other measurements (McDonnell, Carey and Dixon, 1984) at the same epoch. By analysis of trajectories approaching the Earth and its atmosphere, we have shown that a significant contribution could be captured by aerocapture, i.e., atmospheric drag, from either asteroidal or cometary sources; such enhancement is unlikely however to provide the temporal and spatial fluctuations observed by the LDEF Interplanetary Dust Experiment (Mullholland et al. 1992). A further new mechanism is also examined, that of aerofragmentation capture, where an atmospheric grazing trajectory, which would not normally lead to capture, leads to fragmentation by thermal or mechanical shock; the microparticulates thus created can be injected in large numbers, but only into short-lifetime orbits. The concentration in one particular orbit plane, could explain the temporal fluctuations seen on LDEF; space debris could also explain the phenomenon.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Das, P.; Sengupta, D.; CSIR-Central Mechanical Engineering Research Institute, Academy of Scientific and Innovative Research
Highlights: • Thin TiO{sub 2} layer is deposited on conducting substrate using sol–gel based dip coating. • TiO{sub 2} nano-particles are synthesized using hydrothermal route. • Thick TiO{sub 2} particulate layer is deposited on prepared thin layer. • Dye sensitized solar cells are made using thin and thick layer based photo-anode. • Introduction of thin layer in particulate photo-anode improves the cell efficiency. - Abstract: A compact thin TiO{sub 2} passivation layer is introduced between the mesoporous TiO{sub 2} nano-particulate layer and the conducting glass substrate to prepare photo-anode for dye-sensitized solar cell (DSSC). In order to understand the effectmore » of passivation layer, other two DSSCs are also developed separately using TiO{sub 2} nano-particulate and compact thin film based photo-anodes. Nano-particles are prepared using hydrothermal synthesis route and the compact passivation layer is prepared by simply dip coating the precursor sol prepared through wet chemical route. The TiO{sub 2} compact layer and the nano-particles are characterised in terms of their micro-structural features and phase formation behavior. It is found that introduction of a compact TiO{sub 2} layer in between the mesoporous TiO{sub 2} nano-particulate layer and the conducting substrate improves the solar to electric conversion efficiency of the fabricated cell. The dense thin passivation layer is supposed to enhance the photo-excited electron transfer and prevent the recombination of photo-excited electrons.« less
Kuki, Kacilda Naomi; Oliva, Marco Antônio; Pereira, Eduardo Gusmão; Costa, Alan Carlos; Cambraia, José
2008-09-15
Particulate matter is a natural occurrence in the environment, but some industries, such as the iron ore sector, can raise the total amount of particles in the atmosphere. This industry is primarily a source of iron and sulfur dioxide particulates. The effects of the pollutants from the iron ore industries on representatives of restinga vegetation in a Brazilian coastal ecosystem were investigated using physiological and biochemical measures. Two species, Schinus terebinthifolius and Sophora tomentosa, were exposed to simulated deposition of acid mist and iron ore particulate matter in acrylic chambers in a greenhouse. Parameters such as gas exchange, fluorescence emission, chlorophyll content, total iron content, antioxidant enzyme activity and malondialdehyde content were assessed in order to evaluate the responses of the two species. Neither treatment was capable of inducing oxidative stress in S. terebinthifolius. Nevertheless, the deposition of iron ore particulates on this species increased chlorophyll content, the maximum quantum efficiency of photosystem II and the electron transport rate, while iron content was unaltered. On the other hand, S. tomentosa showed a greater sensitivity to the treatments. Plants of S. tomentosa that were exposed to acid mist had a decrease in photosynthesis, while the deposition of iron particulate matter led to an increase in iron content and membrane permeability of the leaves. The activities of antioxidant enzymes, such as catalases and superoxide dismutase, were enhanced by both treatments. The results suggested that the two restinga species use different strategies to overcome the stressful conditions created by the deposition of particulate matter, either solid or wet. It seems that while S. terebinthifolius avoided stress, S. tomentosa used antioxidant enzyme systems to partially neutralize oxidative stress. The findings also point to the potential use of S. tomentosa as a biomarker species under field conditions.
Exposure to Diesel Exhaust Enhances the Generation of Vascular Microparticles
Introduction: In the study of the health impacts of traffic-related air pollution, diesel exhaust is a pollutant of particular interest, since it is a major source of particulate matter (PM). Epidemiological studies associate exposure to ambient levels of PM with cardiovascular m...
ABSTRACT BODY:
Recent investigations have linked neurotrophins including NGF, NT-3, and BDNF to allergic airways diseases. Antibody blockade of NGF attenuates airway resistance associated with allergic airway responses in mice. Mice administered an antibody against the low aff...
Understanding the factors influencing the removal of heavy metals in urban stormwater runoff.
Maniquiz-Redillas, Marla C; Kim, Lee-Hyung
2016-01-01
In this research, an infiltration trench equipped with an extensive pretreatment and filter bed consisting of woodchip, sand and gravel was utilized as a low impact development technique to manage stormwater runoff from a highly impervious road with particular emphasis on heavy metal removal. Findings revealed that the major factors influencing the removal of heavy metals were the concentration of the particulate matters and heavy metals in runoff, runoff volume and flow rates. The reduction of heavy metals was enhanced by sedimentation of particulates through pretreatment. Fine particles (<2 mm) had the most significant amount of heavy metals, thus, enhanced adsorption and filtration using various filter media were important design considerations. Sediment was most highly attached on the surface area of woodchip than to other filter media like sand, gravel and geotextile. It is suggested that maintenance must be performed after the end of the winter season wherein high sediment rate was observed to maintain the efficiency of the treatment system.
Manganese in the shell of the bivalve Mytilus edulis: Seawater Mn or physiological control?
NASA Astrophysics Data System (ADS)
Freitas, Pedro S.; Clarke, Leon J.; Kennedy, Hilary; Richardson, Christopher A.
2016-12-01
Manganese in the shell calcite of marine bivalves has been suggested to reflect ambient seawater Mn concentrations, thus providing a high-resolution archive of past seawater Mn concentrations. However, a quantitative relationship between seawater Mn and shell Mn/Ca ratios, as well as clear understanding of which process(es) control(s) shell Mn/Ca, are still lacking. Blue mussels, Mytilus edulis, were grown in a one-year duration field experiment in the Menai Strait, U.K., to study the relationship between seawater particulate and dissolved Mn2+ concentrations and shell calcite Mn/Ca ratios. Shell Mn/Ca showed a well-defined intra-annual double-peak, with maximum values during early spring and early summer and low values during autumn and winter. Seawater particulate Mn peaked during winter and autumn, with a series of smaller peaks during spring and summer, whereas dissolved Mn2+ exhibited a marked single maximum during late-spring to early-summer, being low during the remainder of the year. Consequently, neither seawater particulate Mn nor dissolved Mn2+ concentrations explain the intra-annual variation of shell Mn/Ca ratios. A physiological control on shell Mn/Ca ratios is evident from the strong similarity and timing of the double-peaked intra-annual variations of Mn/Ca and shell growth rate (SGR), the latter corresponding to periods of increased metabolic activity (as indicated by respiration rate). It is thus likely that in M. edulis SGR influences shell Mn/Ca by altering the concentration or activity of Mn2+ within the extra-pallial fluid (EPF), by changing the flux of Mn into or the proportion of protein bound Mn within the EPF. By linking shell Mn/Ca ratios to the endogenous and environmental factors that determine growth and metabolic activity, this study helps to explain the lack of a consistent relationship between shell Mn/Ca in marine bivalve shell calcite and seawater particulate and dissolved Mn2+ concentrations. The use of Mn content from M. edulis shell calcite as a proxy for the dissolved and/or particulate Mn concentrations, and thus the biogeochemical processes that control them, remains elusive.
Characterizing mineral dusts and other aerosols from the Middle East--Part 1: ambient sampling.
Engelbrecht, Johann P; McDonald, Eric V; Gillies, John A; Jayanty, R K M; Casuccio, Gary; Gertler, Alan W
2009-02-01
The purpose of the Enhanced Particulate Matter Surveillance Program was to provide scientifically founded information on the chemical and physical properties of dust collected over a period of approximately 1 year in Djibouti, Afghanistan (Bagram, Khowst), Qatar, United Arab Emirates, Iraq (Balad, Baghdad, Tallil, Tikrit, Taji, Al Asad), and Kuwait (northern, central, coastal, and southern regions). Three collocated low-volume particulate samplers, one each for the total suspended particulate matter, < 10 micro m in aerodynamic diameter (PM(10)) particulate matter, and < 2.5 micro m in aerodynamic diameter (PM(2.5)) particulate matter, were deployed at each of the 15 sites, operating on a '1 in 6' day sampling schedule. Trace-element analysis was performed to measure levels of potentially harmful metals, while major-element and ion-chemistry analyses provided an estimate of mineral components. Scanning electron microscopy with energy dispersive spectroscopy was used to analyze the chemical composition of small individual particles. Secondary electron images provided information on particle size and shape. This study shows the three main air pollutant types to be geological dust, smoke from burn pits, and heavy metal condensates (possibly from metals smelting and battery manufacturing facilities). Non-dust storm events resulted in elevated trace metal concentrations in Baghdad, Balad, and Taji in Iraq. Scanning-electron-microscopy secondary electron images of individual particles revealed no evidence of freshly fractured quartz grains. In all instances, quartz grains had rounded edges and mineral grains were generally coated by clay minerals and iron oxides.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Toops, Todd J.; Bilheux, Hassina Z.; Voisin, Sophie
2013-08-19
This research describes the development and implementation of high-fidelity neutron imaging and the associated analysis of the images. This advanced capability allows the non-destructive, non-invasive imaging of particulate filters (PFs) and how the deposition of particulate and catalytic washcoat occurs within the filter. The majority of the efforts described here were performed at the High Flux Isotope Reactor (HFIR) CG-1D neutron imaging beamline at Oak Ridge National Laboratory; the current spatial resolution is approximately 50 μm. The sample holder is equipped with a high-precision rotation stage that allows 3D imaging (i.e., computed tomography) of the sample when combined with computerizedmore » reconstruction tools. What enables the neutron-based image is the ability of some elements to absorb or scatter neutrons where other elements allow the neutron to pass through them with negligible interaction. Of particular interest in this study is the scattering of neutrons by hydrogen-containing molecules, such as hydrocarbons (HCs) and/or water, which are adsorbed to the surface of soot, ash and catalytic washcoat. Even so, the interactions with this adsorbed water/HC is low and computational techniques were required to enhance the contrast, primarily a modified simultaneous iterative reconstruction technique (SIRT). Lastly, this effort describes the following systems: particulate randomly distributed in a PF, ash deposition in PFs, a catalyzed washcoat layer in a PF, and three particulate loadings in a SiC PF.« less
Prouty, Nancy G.; Mienis, Furu; Campbell, P.; Roark, E. Brendan; Davies, Andrew; Robertson, Craig M.; Duineveld, Gerard; Ross, Steve W.; Rhodes, M.; Demopoulos, Amanda W.J.
2017-01-01
Submarine canyons are often hotspots of biomass and productivity in the deep sea. However, the majority of deep-sea canyons remain poorly sampled. Using a multi-tracer approach, results from a detailed geochemical investigation from a year-long sediment trap deployment reveals details concerning the source, transport, and fate of particulate matter to the depositional zone (1318 m) of Baltimore Canyon on the US Mid-Atlantic Bight (MAB). Both organic biomarker composition (sterol and n-alkanes) and bulk characteristics (δ13C, Δ14C, Chl-a) suggest that on an annual basis particulate matter from marine and terrestrially-derived organic matter are equally important. However, elevated Chlorophyll-a and sterol concentrations during the spring sampling period highlight the seasonal influx of relatively fresh phytodetritus. In addition, the contemporaneous increase in the particle reactive elements cadmium (Cd) and molybdenum (Mo) in the spring suggest increased scavenging, aggregation, and sinking of biomass during seasonal blooms in response to enhanced surface production within the nutricline. While internal waves within the canyon resuspend sediment between 200 and 600 m, creating a nepheloid layer rich in lithogenic material, near-bed sediment remobilization in the canyon depositional zone is minimal. Instead, vertical transport and lateral transport across the continental margin are the dominant processes driving seasonal input of particulate matter. In turn, seasonal variability in deposited particulate organic matter may be linked to benthic faunal composition and ecosystem scale carbon cycling.
Air cleaning performance of a new environmentally controlled primary crusher operator booth
Organiscak, J.A.; Cecala, A.B.; Zimmer, J.A.; Holen, B.; Baregi, J.R.
2016-01-01
The National Institute for Occupational Safety and Health (NIOSH) cooperated with 3M Company in the design and testing of a new environmentally controlled primary crusher operator booth at the company’s Wausau granite quarry near Wausau, WI. This quarry had an older crusher booth without a central heating, ventilation and air conditioning (HVAC) system, and without an air filtration and pressurization system. A new replacement operator booth was designed and installed by 3M based on design considerations from past NIOSH research on enclosed cab filtration systems. NIOSH conducted pre-testing of the old booth and post-testing of the new booth to assess the new filtration and pressurization system’s effectiveness in controlling airborne dusts and particulates. The booth’s dust and particulate control effectiveness is described by its protection factor, expressed as a ratio of the outside to inside concentrations measured during testing. Results indicate that the old booth provided negligible airborne respirable dust protection and low particulate protection from the outside environment. The newly installed booth provided average respirable dust protection factors from 2 to 25 over five shifts of dust sampling with occasional worker ingress and egress from the booth, allowing some unfiltered contaminants to enter the enclosure. Shorter-term particle count testing outside and inside the booth under near-steady-state conditions, with no workers entering or exiting the booth, resulted in protection factors from 35 to 127 on 0.3- to 1.0-μm respirable size particulates under various HVAC airflow operating conditions. PMID:26937052
NASA Astrophysics Data System (ADS)
Näthe, Kerstin; Michalzik, Beate; Levia, Delphis; Steffens, Markus
2016-04-01
Fires represent an ecosystem disturbance and are recognized to seriously pertubate the nutrient budgets of forested ecosystems. While the effects of fires on chemical, biological, and physical soil properties have been intensively studied, especially in Mediterranean areas and North America, few investigations examined the effects of fire-induced alterations in the water-bound fluxes and the chemical composition of dissolved and particulate organic carbon and nitrogen (DOC, POC, DN, PN). The exclusion of the particulate organic matter fraction (0.45 μm < POM < 500 μm) potentially results in misleading inferences and budgeting gaps when studying the effects of fires on nutrient and energy fluxes. To our best knowledge, this is the first known study to present fire-induced changes on the composition of dissolved and total organic matter (DOM, TOM) in forest floor (FF) and soil solutions (A, B horizon) from Scots pine forests in Germany. In relation to control sites, we test the effects of low-severity fires on: (1) the composition of DOM and TOM in forest floor and soil solutions; and (2) the translocated amount of particulate in relation to DOC and DN into the subsoil. The project aims to uncover the mechanisms of water-bound organic matter transport along an ecosystem profile and its compositional changes following a fire disturbance. Forest floor and soil solutions were fortnightly sampled from March to December 2014 on fire-manipulated and control plots in a Scots pine forest in Central Germany. Shortly after the experimental duff fire in April 2014 pooled solutions samples were taken for solid-state 13C NMR spectroscopy to characterize DOM (filtered solution < 0.8μm pore size) and TOM in unfiltered solutions. Independent from fire manipulation, the composition of TOM was generally less aromatic (aromaticity index [%] according to Hatcher et al., 1981) with values between 18 (FF) - 25% (B horizon) than the DOM fraction with 23 (FF) - 27% (B horizon). For DOM in FF solution, fire manipulation caused an increase in aromaticity from 23 to 27% compared to the control, due to an increase of the aryl-C and a decrease of the O-alkyl-C and alkyl-C signal. Fire effects were leveled out in the mineral soil. For TOM, fire effects became notable only in the A horizon, exhibiting a decrease in aromaticity from 22 to 18% compared to the control, due to increased O-alkyl-C and diminished aryl-C proportions. Compared to the control, fire only caused minor DOC release rates (< 10%) in the FF and mineral soil, while DN in the FF was significantly mobilized (+ 40%) by fire exhibiting annual values of 33 at the control sites compared to 46 kg DN ha-1 at the fire treated sites. Compared to the control, fire events did not significantly enhance the proportion of POC and PN in the total C and N amounts exhibiting values between 10 and 20%. To fully understand the quality and amount of translocated organic C and N compounds within soils under both ambient as well as fire environments, dissolved and particulate size fractions need to be considered.
Performance and emissions characteristics of aqueous alcohol fumes in a DI diesel engine
NASA Technical Reports Server (NTRS)
Heisey, J. B.; Lestz, S. S.
1981-01-01
A single cylinder DI Diesel engine was fumigated with ethanol and methanol in amounts up to 55% of the total fuel energy. The effects of aqueous alcohol fumigation on engine thermal efficiency, combustion intensity and gaseous exhaust emissions were determined. Assessment of changes in the biological activity of raw particulate and its soluble organic fraction were also made using the Salmonella typhimurium test. Alcohol fumigation improved thermal efficiency slightly at moderate and heavy loads, but increased ignition delay at all operating conditions. Carbon monoxide and unburned hydrocarbon emission generally increased with alcohol fumigation and showed no dependence on alcohol type or quality. Oxide of nitrogen emission showed a strong dependence on alcohol quality; relative emission levels decreased with increasing water content of the fumigant. Particulate mass loading rates were lower for ethanol fueled conditions. However, the biological activity of both the raw particulate and its soluble organic fraction was enhanced by ethanol fumigation at most operating conditions.
Integrated current collector and catalyst support
Bregoli, Lawrence J.
1985-10-22
An integrated current collecting electrode for a molten carbonate fuel cell includes a corrugated metal conductive strip positioned in contact with a catalyst layer. The corrugations of the metal strip form a plurality of gas channels immediately adjacent the surface of the catalyst through which a reactant gas flows. Each channel is filled with a particulate material to maintain separation between the metal strip and the catalyst in ensuring gas channel integrity. The catalyst may be in the form of a compacted, particulate material provided the particle size of the material within the gas channels is larger than that of the catalyst particles to prevent catalyst migration to the metal conductor and provide reactant gas access to the catalyst layer. The gas channels formed by the corrugations of the metal strip are arranged in an offset pattern along the direction of gas flow for improved reactant gas distribution to the catalyst layer. The particulate material positioned within the gas flow channels may be a ceramic conductor such as a perovskite or a spinel for enhanced current collection.
Integrated current collector and catalyst support
Bregoli, L.J.
1984-10-17
An integrated current collecting electrode for a molten carbonate fuel cell includes a corrugated metal conductive strip positioned in contact with a catalyst layer. The corrugations of the metal strip form a plurality of gas channels immediately adjacent the surface of the catalyst through which a reactant gas flows. Each channel is filled with a particulate material to maintain separation between the metal strip and the catalyst in ensuring gas channel integrity. The catalyst may be in the form of a compacted, particulate material provided the particle size of the material within the gas channels is larger than that of the catalyst particles to prevent catalyst migration to the metal conductor and provide reactant gas access to the catalyst layer. The gas channels formed by the corrugations of the metal strip are arranged in an offset pattern along the direction of gas flow for improved reactant gas distribution to the catalyst layer. The particulate material positioned within the gas flow channels may be a ceramic conductor such as a perovskite or a spinel for enhanced current collection.
Tomei, M C; Braguglia, C M; Mininni, G
2008-09-01
Degradation kinetics of particulate matter in anaerobic digestion of secondary sludge, untreated and sonicated, was investigated by carrying out batch tests at different feed/inoculum ratio (F/I) (in the range of 0.1-4.0). Particulate COD degradation data were analysed using the four equations most widely utilized to model the hydrolysis process and the related kinetic parameters were evaluated. The increase of F/I results in a correspondent increase of the process rate up to one order of magnitude in the investigated interval for both untreated and sonicated sludge. The maximum step increase is observed in the range of 0.1-2.0 while for F/I varying from 2.0 to 4.0 only a modest enhancement of the process kinetics is detected. The effect of sonication on kinetics is not appreciable at low F/I, due to the low fraction of fed sludge and to the consequent strong substrate limitation, whereas at high F/I a slight increase is evidenced.
Co-transport of gold nanospheres with single-walled carbon nanotubes in saturated porous media.
Afrooz, A R M Nabiul; Das, Dipesh; Murphy, Catherine J; Vikesland, Peter; Saleh, Navid B
2016-08-01
Porous media transport of engineered nanomaterials (ENMs) is typically assessed in a controlled single-particulate environment. Presence of a secondary particle (either natural or engineered) in the natural environment though likely, is rarely taken into consideration in assessing ENMs' transport behavior. This study systematically assesses the effect of a secondary ENM (i.e., pluronic acid modified single-walled carbon nanotubes, PA-SWNTs) on a primary particle (i.e., gold nanospheres, AuNSs) transport through saturated porous media under a wide range of aquatic conditions (1-100 mM NaCl). AuNS hetero-dispersions (i.e., with PA-SWNTs) are transported through saturated sand columns, and the transport behavior is compared to AuNS-only homo-dispersion cases, which display classical ionic strength-dependent behavior. AuNS hetero-dispersion, however, is highly mobile with little to no ionic strength-dependent effects. This study also assesses the role of pre-coating of the collectors with PA-SWNTs on AuNSs' mobility, thereby elucidating the role played by the order of introduction of the secondary particles. Pre-existence of the secondary particles in the porous media shows enhanced filtration of primary AuNSs. However, the presence of natural organic matter (NOM) slightly increases AuNS mobility through PA-SWNT coated sand at 10 mM ionic strength. The study results demonstrate that the presence and order of addition of the secondary particles strongly influence primary particles' mobility. Thus ENMs can demonstrate facilitated transport or enhanced removal, depending on the presence of the secondary particulate matter and background solution chemistry. Copyright © 2016 Elsevier Ltd. All rights reserved.
Zhang, Yiming; Mikhaylova, Lyudmila; Kobzik, Lester; Fedulov, Alexey V
2015-01-01
Innate defenses against environmental particulate exposures can become deficient when physiological background of the organism is unbalanced. Even those exposures considered innocuous may then become harmful. For example, one of the important inherent risks of pregnancy is increased inflammatory responsiveness in the airways, which extends to exposures considered otherwise innocuous: it has been observed that normally "inert" particulates become inflammatory in pregnancy. They lead to enhanced airway inflammation associated with increased asthma risk in the offspring in the BALB/c model. It was hypothesized that pregnancy hormones alter macrophageal uptake and clearance of particles. This study shows that the phagocytic activity of alveolar macrophages (AM) and RAW264.7 cells against titanium dioxide (TiO2) was inhibited in pregnancy by ∼ 10% and in vitro by estradiol by ∼ 20%; progesterone potentiated this effect. Hence, enhanced inflammation in pregnancy as an outcome of exposure to the "inert" TiO2 may be due to an effect of pregnancy hormones which decrease the ability of the airways to clear the particles. AM (at 10(6) cells/recipient) isogenically transplanted from pregnant mothers into airways of recipients were able to confer the phenotype of inflammatory response to TiO2 (PMN counts of 1.62 [± 0.19] × 10(5)/ml versus 0.61 [± 0.13] × 10(5)/ml in control). Because this small amount of transferred AM could not replace the AM population in the recipients' lungs, it is postulated that the effect is mediated by inhibitory signaling factors that AM produce and release; hence, a list of probable molecules was identified via genome-wide microarray.
NASA Astrophysics Data System (ADS)
Samanta, Saumik; Dalai, Tarun K.
2016-12-01
In this study, the sources and the cycling of Ba have been evaluated in the Ganga (Hooghly) River estuary using the composition of the suspended sediments and the water samples collected during six seasons of contrasting water discharge over two years (2012 and 2013). In addition, the data on the samples of groundwater from areas adjacent to the estuary, and the industrial effluent water and urban wastewater draining into the estuary are presented. Selective extraction experiments were also performed on the suspended particulate matter of two seasons to assess the distribution of exchangeable concentrations of major ions and Ba. In the mixing zone, the variation patterns of the dissolved Ba concentrations show mid-salinity maxima and are similar to the patterns of variation of the particulate Mg/Al and Mg/Fe, suggesting that the production of dissolved Ba is linked to the adsorption of major ions on to the clay minerals and Fe-Mn oxyhydroxides in the particulate matter. The inference of coupled adsorption-desorption processes is supported by the observations that the particulate Ba/Mg and Ba/K ratios exhibit significant to strong negative correlations with the concentrations of Al, Fe and Mn. The observations of mid-salinity maxima for the concentrations of exchangeable Mg and K, and of the exchangeable Ba concentrations that decrease with salinity provide strong evidence that the solute-particle interactions is the major driver in regulating the dissolved Ba distributions in the estuary. The estimates of the quantity of desorbed Ba based on three different approaches suggest that desorption is sufficient to account for the calculated excess Ba (Baxs) concentrations. The contribution of Ba to the dissolved load via dissolution of the particulate carbonate phases is minor, up to 3% of the maximum Baxs concentrations. The estimates of anthropogenic contributions are insignificant, and account for ⩽2% of maximum Baxs in the estuary. Groundwater contributions are less significant and account for up to 5% of the annual Ba flux from the Hooghly estuary. The estimates of Ba flux show that annually (1.5-1.9) × 107 moles of Ba is transported by the Hooghly River. About (3.6-4.3) × 107 moles of Ba is generated annually in the estuary through desorption. Added together, the desorbed and riverine Ba fluxes generate a total Ba flux of (5.1-6.2) × 107 moles per year. Thus, the solute-particle interactions enhance the riverine Ba flux by >300%. A compilation of the available data shows that the enhancement of the riverine Ba flux and the fractions of desorbed Ba flux scale with (particulate matter flux/water flux) ratio in several estuaries of the world, suggesting that the process of solute-particle interactions is a major driver for the estuarine production of Ba on a global scale. Among the rivers considered in this study, the estuaries of the Hooghly River and the Ganges-Brahmaputra rivers, characterized by very high (sediment flux/water flux) ratio, depict the highest increase in the riverine Ba flux. This unique feature of the Ganga River system is inferred to be resulting from the collective impact of the tectonic activity and the monsoonal rainfall in the catchment areas.
Respiratory deposition of inhaled micron particles in subjects with mild asthma
Rational: Particulate matter (PM) in the ambient air can cause adverse health effects to some people including an aggravation of asthma. Although compromised lung conditions in disease are likely to be the primary cause of the effects, enhanced respiratory dose of particles may a...
Connecting the Visible World with the Invisible
ERIC Educational Resources Information Center
Pentecost, Thomas; Weber, Sarah; Herrington, Deborah
2016-01-01
Research suggests that connecting the visible (macroscopic) world of chemical phenomena to the invisible (particulate) world of atoms and molecules enhances student understanding in chemistry. This approach aligns with the science standards and is fundamental to the redesigned AP Chemistry curriculum. However, chemistry is usually taught at the…
Rationale: Intravascular thrombosis and platelet aggregation are enhanced following exposure to diesel exhaust (DE) and other respirable particulate matter; however, the roles of endothelial and circulating mediators on platelet aggregation remain unclear. We hypothesized that ad...
This study demonstrates that early-life persistent vitamin D deficiency alters the cardiopulmonary response to smog in mice and may increase risk of adverse effects. Early life nutritional deficiencies can lead to increased cardiovascular susceptibility to environme...
Method to Select Metropolitan Areas of Epidemiologic Interest for Enhanced Air Quality Monitoring
The U.S. Environmental Protection Agency’s current Speciation Trends Network (STN) covers most major U.S. metropolitan areas and a wide range of particulate matter (PM) constituents and gaseous co-pollutants. However, using filter-based methods, most PM constituents are measured ...