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Jamming and Stress Propagation in Particulate Matter  [PDF]
M. E. Cates,J. P. Wittmer,J. -P. Bouchaud,P. Claudin
Physics , 1998, DOI: 10.1016/S0378-4371(98)00491-9
Abstract: We present simple models of particulate materials whose mechanical integrity arises from a jamming process. We argue that such media are generically "fragile", that is, they are unable to support certain types of incremental loading without plastic rearrangement. In such models, fragility is naturally linked to the marginal stability of force chain networks (granular skeletons) within the material. Fragile matter exhibits novel mechanical responses that may be relevant to both jammed colloids and cohesionless assemblies of poured, rigid grains.
Electrochemical Characteristics of Particulate Matter
Margarita Baitimirova, Agnese Osite, Juris Katkevich, Arturs Viksna
Scientific Journal of Riga Technical University. Environmental and Climate Technologies , 2011, DOI: 10.2478/v10145-011-0023-1
Abstract: The current work is dedicated to electrochemical impedance spectra analysis of the fine and coarse airborne particulate matter sampled on the glass fibre filters in Riga city air. The cyclic voltammograms, impedance spectra and double layer capacitance spectra of particulate matter were obtained after the pre-treatment of samples. The equivalent circuit method and the statistical method were used for impedance spectra analysis. Analyzing the impedance spectra, it was concluded that the impedance of both - fine and coarse particles heated in N2 flow does not change by aerosol mass concentration variations. On the other hand, the impedance of particulate matter heated in O2 flow increases, by increasing PM10 mass concentration. Describing the spectra of double layer capacitance, it was observed that the double layer capacitance of aerosols heated in N2 flow did not change, by mass concentration and size variations. However, by increasing mass concentration of coarse aerosols heated in O2 flow, the double layer capacitance reduced.
Particulate matter dynamics  [PDF]
Rodolfo G. Cionco,Nancy E. Quaranta,Marta G. Caligaris
Physics , 2012,
Abstract: A substantial fraction of the particulate matter released into the atmosphere by industrial or natural processes corresponds to particles whose aerodynamic diameters are greater than 50 mm. It has been shown that, for these particles, the classical description of Gaussian plume diffusion processes, is inadequate to describe the transport and deposition. In this paper we present new results concerning the dispersion of coarse particulate matter. The simulations are done with our own code that uses the Bulirsch Stoer numerical integrator to calculate threedimensional trajectories of particles released into the environment under very general conditions. Turbulent processes are simulated by the Langevin equation and weather conditions are modeled after stable (Monin-Obukhov length L> 0) and unstable conditions (L <0). We present several case studies based on Monte Carlo simulations and discusses the effect of weather on the final deposition of these particles.
Charge without charge in quarks  [PDF]
Harry Schiff
Physics , 2013,
Abstract: With appropriate gauge transformations, field can replace electric charge in quarks. Classical quarks, in a necessary non-gauge invariant formulation, are used for illustration, bringing to the fore the limitations of the usual electric charge densities for single particles in Coulomb equations. The results are encouraging; the solutions for the Coulomb potentials apply individually to each quark in a shell structure. A remarkably simple relation emerges between the Coulomb and weak potentials.
Impact of cascade hydropower stations on suspended particulate matter in Xiangxi River
梯级水电站开发对香溪河悬浮颗粒物粒径及浓度的影响

HAN Shuang,DONG Zheng-Ju,WANG Huan,CAI Qing-Hu,DENG Hong-Bing,WU Gang,
韩霜
,董正举,王欢,蔡庆华,邓红兵,吴钢

生态学报 , 2008,
Abstract: Based on the experimental data of size and concentration of suspended particle on Xiangxi River, the characters of size and concentration of suspended particle changed by the cascade hydropower stations were studied. The results showed that the size of suspended particulate matter (SPM) decreased from upstream to middle reaches, and changed from medium-large particulate matter to fine particulate matter. Without disturbance of hydropower stations, the decrease extent of size was more significant. No obvious differences were observed among the sizes of SPM at different sites from inlet to outlet of 26 typical cascade hydropower stations in the whole watershed. The concentration of total particulate matter increased at some special sites because of the disturbance of hydropower stations. It was showed that there was on obvious influence of hydropower stations on the concentration of particulate organic matter. The size and concentration of suspended particle diversification were related to flow velocity and water flow.
Simultaneously catalytic removal of NO x and particulate matter on diesel particulate filter
Guanghui Liu,Zhen Huang,Wenfeng Shangguan,Cunxian Yan
Chinese Science Bulletin , 2003, DOI: 10.1007/BF03183304
Abstract: The simultaneous removal of NOx and particulate matter (PM) exhausted from diesel engine was studied with a diesel particulate filter (DPF) on which a mixed metal oxide catalyst, Cu0.95K0.05Fe2O4 was loaded. The NO x reduction was observed in the same temperature range of the CO2 formation, implying the occurrence of the simultaneous removal of NO x and PM in an oxidizing atmosphere. It was shown that SOF and soot in PM are attributed to the reduction of NO x at lower and higher temperatures, respectively. The oxidation of PM was enhanced by the coexistence of NO and O2. The ignition and exhaustion temperatures of PM decrease as the order NO>O2>NO+O2. This is a combined process of PM trapping as well as the catalytic reactions of soot oxidation and NOx reduction, promising the most desirable after-treatment of diesel exhausts.
Particulate Matter Concentrations in the Vicinity of an Incinerator  [PDF]
Kristine Walungama Endjambi, Onjefu Sylvanus Ameh, Nnenesi Kgabi, Innocent Maposa, Ndinomholo Hamatui
Journal of Geoscience and Environment Protection (GEP) , 2016, DOI: 10.4236/gep.2016.412007
Abstract: Incineration is an effective way of health care waste management, but it is also a source of air pollution. Thermal decomposition of organic and inorganic waste during incineration releases a large concentration of air pollutants such as CO, SO2, NOx, CO2 and particulate matter (PM). A cross sectional-descriptive study was conducted to determine the short-term variations in PM concentrations across various areas in the vicinity of a local incinerator in Windhoek, Namibia. XRF Qualitative analysis method was used to determine the elemental composition of fallout dust concentration from six study areas/stations in the vicinity of a local incinerator. Single bucket fallout monitors were deployed following the American Society for Testing and Materials standard method for collection and analysis of dust fallout to determine the elemental composition of fallout dust. Real-time PM concentration trends were also recorded using a portable Micro dust Pro Real-time Dust Monitor for PM10 at a height of 2.2 m above the ground. High PM concentration peaks were observed in the morning and afternoon hours at varying points. The fallout dust rate ranged between highest 1839.3 mg/m2/day at sampling Point 4 and lowest 711 mg/m2/day at sampling Point 2. The XRF analysis revealed the presence of toxic elements and crustal elements in order of decreasing abundance: Mn > Zn > Cr > V > Zr > Sr > Pb > Ni and SI > K > Fe > Ti > Ca > Al > P respectively. Highest elemental composition concentrations were found at sampling location in the vicinity of the incinerator and in industrial area.
Notes on the Particulate Matter Standards in the European Union and the Netherlands  [PDF]
Hugo Priemus,Elizabeth Schutte-Postma
International Journal of Environmental Research and Public Health , 2009, DOI: 10.3390/ijerph6031155
Abstract: The distribution of Particulate Matter in the atmosphere, resulting from emissions produced by cars, trucks, ships, industrial estates and agricultural complexes, is a topical public health problem that has increased in recent decades due to environmental factors in advanced economies in particular. This contribution relates the health impact caused by concentrations of Particulate Matter (PM) in ambient air to the PM standards, the size of the particles and spatial planning. Diverging impacts of PM standards in legal regulation are discussed. The authors present a review of the development of legal PM standards in the European Union, with a specific reference to The Netherlands.
Simultaneously catalytic removal of NOx and particulate matter on diesel particulate filter
Liu Guanghui,HUANG Zhen,SHANGGUAN Wenfeng,YAN Cunxian,
LIU Guanghui
,HUANG Zhen,SHANGGUAN Wenfeng & YAN Cunxian School of Mechanical and Power Engineering,Shanghai Jiao Tong Uni-versity,Shanghai,China

科学通报(英文版) , 2003,
Abstract: The simultaneous removal of NOx and particu-late matter (PM) exhausted from diesel engine was studied with a diesel particulate filter (DPF) on which a mixed metal oxide catalyst, Cu0.95K0.05Fe2O4 was loaded. The NOx reduc-tion was observed in the same temperature range of the CO2 formation, implying the occurrence of the simultaneous re-moval of NOx and PM in an oxidizing atmosphere. It was shown that SOF and soot in PM are attributed to the reduc-tion of NOx at lower and higher temperatures, respectively. The oxidation of PM was enhanced by the coexistence of NO and O2. The ignition and exhaustion temperatures of PM decrease as the order NO>O2>NO+O2. This is a combined process of PM trapping as well as the catalytic reactions of soot oxidation and NOx reduction, promising the most de-sirable after-treatment of diesel exhausts.
Current state of particulate matter research and management in Serbia (Introductory paper)  [PDF]
Milena Jova?evi?-Stojanovi?,Alena Bartonova
Chemical Industry and Chemical Engineering Quarterly , 2010,
Abstract: Particulate matter is the air pollutant that currently receives most attention from the atmospheric research community, the legislative authorities and the general public. Limiting particulate matter in the atmosphere which will result in significant benefits for human health, with associated positive economic consequences. Successful management of particulate matter requires scientific knowledge about particulate matter “from cradle to grave”, covering sources of particles, processes that govern their formation, composition, dispersion and fate in the atmosphere, as well as knowledge about human exposure and associated health and well being. Such knowledge allows to design and perform effective and efficient abatement measures and monitoring. This paper provides an introduction to the research and monitoring regarding particulate matter in Serbia. The contributions were first partly presented at the 2nd international workshop of the WeBIOPATR “Outdoor concentration, size distribution and composition of respirable particles in WB urban area” project in September 2009. This information provides context to the contributions in this number, and was part of the rationale of the project WeBIOPATR.
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