WorldWideScience

Sample records for pollution precipitation chemistry

  1. Atmospheric Chemistry and Air Pollution

    Directory of Open Access Journals (Sweden)

    Jeffrey S. Gaffney

    2003-01-01

    Full Text Available Atmospheric chemistry is an important discipline for understanding air pollution and its impacts. This mini-review gives a brief history of air pollution and presents an overview of some of the basic photochemistry involved in the production of ozone and other oxidants in the atmosphere. Urban air quality issues are reviewed with a specific focus on ozone and other oxidants, primary and secondary aerosols, alternative fuels, and the potential for chlorine releases to amplify oxidant chemistry in industrial areas. Regional air pollution issues such as acid rain, long-range transport of aerosols and visibility loss, and the connections of aerosols to ozone and peroxyacetyl nitrate chemistry are examined. Finally, the potential impacts of air pollutants on the global-scale radiative balances of gases and aerosols are discussed briefly.

  2. Dilution physics modeling: Dissolution/precipitation chemistry

    International Nuclear Information System (INIS)

    Onishi, Y.; Reid, H.C.; Trent, D.S.

    1995-09-01

    This report documents progress made to date on integrating dilution/precipitation chemistry and new physical models into the TEMPEST thermal-hydraulics computer code. Implementation of dissolution/precipitation chemistry models is necessary for predicting nonhomogeneous, time-dependent, physical/chemical behavior of tank wastes with and without a variety of possible engineered remediation and mitigation activities. Such behavior includes chemical reactions, gas retention, solids resuspension, solids dissolution and generation, solids settling/rising, and convective motion of physical and chemical species. Thus this model development is important from the standpoint of predicting the consequences of various engineered activities, such as mitigation by dilution, retrieval, or pretreatment, that can affect safe operations. The integration of a dissolution/precipitation chemistry module allows the various phase species concentrations to enter into the physical calculations that affect the TEMPEST hydrodynamic flow calculations. The yield strength model of non-Newtonian sludge correlates yield to a power function of solids concentration. Likewise, shear stress is concentration-dependent, and the dissolution/precipitation chemistry calculations develop the species concentration evolution that produces fluid flow resistance changes. Dilution of waste with pure water, molar concentrations of sodium hydroxide, and other chemical streams can be analyzed for the reactive species changes and hydrodynamic flow characteristics

  3. MAP3S precipitation chemistry network: fourth periodic summary report (1980)

    Energy Technology Data Exchange (ETDEWEB)

    1981-12-01

    This, the fourth in a series of summary reports, contains complete field and chemical data from the MAP3S/RAINE (Multistate Atmospheric Power Production Pollution Studies) Precipitation Chemistry Network for the year 1980. The 1980 data were added to the previous data base, and an update of the previous statistical summary completed. Included are basic statistics, time trend analyses, and monthly averages.

  4. Investigation of Varied Strontium-Transuranic Precipitation Chemistries for Crossflow

    International Nuclear Information System (INIS)

    Nash, C.A.

    2000-01-01

    Precipitation chemistries for strontium and transuranic (TRU) removal have been tested for crossflow filterability and lanthanide removal with simulants of Hanford tank 241-AN-107 supernate. This is the initial work indicating the usefulness of a strontium and permanganate precipitation process as applied to the Hanford River Protection Project. Precipitations with both ferric and ferrous iron were shown to be at least two orders of magnitude less filterable than a 0.1 gpm/ft target average flux that was desired at the time. A precipitate from a strontium nitrate strike alone was found to filter easily and to make the desired average flux. Other chemistries tested included precipitant of lanthanum(III), nickel (II), calcium (II), and a redox chemistry using sodium permanganate. Of these chemistries a strontium and permanganate strike including calcium provided the highest filter flux compared to the other chemistries. It showed the most promise in lanthanide removal as well. This work provides a promising direction for further work to achieve both acceptable filterability and decontamination for Envelope C wastes to be treated by the Hanford River Protection Project. The work reported here was originally intended to satisfy needs for crossflow filter testing of a strontium and ferric precipitation method for treating Envelope C using a 241-AN-107 simulant

  5. Investigation of Varied Strontium-Transuranic Precipitation Chemistries for Crossflow

    Energy Technology Data Exchange (ETDEWEB)

    Nash, C.A.

    2000-07-27

    Precipitation chemistries for strontium and transuranic (TRU) removal have been tested for crossflow filterability and lanthanide removal with simulants of Hanford tank 241-AN-107 supernate. This is the initial work indicating the usefulness of a strontium and permanganate precipitation process as applied to the Hanford River Protection Project. Precipitations with both ferric and ferrous iron were shown to be at least two orders of magnitude less filterable than a 0.1 gpm/ft target average flux that was desired at the time. A precipitate from a strontium nitrate strike alone was found to filter easily and to make the desired average flux. Other chemistries tested included precipitant of lanthanum(III), nickel (II), calcium (II), and a redox chemistry using sodium permanganate. Of these chemistries a strontium and permanganate strike including calcium provided the highest filter flux compared to the other chemistries. It showed the most promise in lanthanide removal as well. This work provides a promising direction for further work to achieve both acceptable filterability and decontamination for Envelope C wastes to be treated by the Hanford River Protection Project. The work reported here was originally intended to satisfy needs for crossflow filter testing of a strontium and ferric precipitation method for treating Envelope C using a 241-AN-107 simulant.

  6. Trends of two decadal precipitation chemistry in a subtropical rainforest in East Asia.

    Science.gov (United States)

    Chang, Chung-Te; Wang, Chiao-Ping; Huang, Jr-Chuan; Wang, Lih-Jih; Liu, Chiung-Pin; Lin, Teng-Chiu

    2017-12-15

    Long-term monitoring of precipitation chemistry provides a great opportunity to examine the evolution of air pollutant emissions and effectiveness of air pollution control measures. We evaluated the characteristics and trends of precipitation chemistry at both annual and seasonal scales based on the records of 1994-2013 at Fushan Experimental Forest (FEF) of northeastern Taiwan. The results showed that 77% of the weekly precipitation had pHprecipitation pH and the difference between [SO 4 2 - +NO 3 - ] and [Ca 2+ +NH 4 + ], not just [SO 4 2 - +NO 3 - ], suggesting that precipitation acidity was not solely determined by acidic pollutants but by the balance between acidic pollutants and base cations. We also found temporal decreases of Ca 2+ and NH 4 + concentrations in precipitation which contributed to the low acid neutralization capacity of precipitation. Annual deposition of NO 3 - and SO 4 2- was 23 and 55kgha -1 yr -1 , which is much higher than most forest sites in the industrialized countries suggesting that acid deposition is still a major environmental issue in Taiwan. Annual deposition of NH 4 + , Ca 2+ and NO 3 - showed significant decreasing trends during the 20-year period, which was mostly due to the decreases in the summer deposition associated with air pollution mitigation strategies. Winter deposition showed no decreasing patterns for the same period. The high contribution to annual acid deposition from autumn-winter and spring rains (50%) associated with northeast monsoon implies that long-range transport of anthropogenic emissions from East Asia played a key role on acid depositions at FEF and possibly many areas in the region. Therefore, intergovernmental cooperation is urgently needed to effectively mitigate the threat of acid deposition in East Asia. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Statistical methodology for exploring elevational differences in precipitation chemistry

    International Nuclear Information System (INIS)

    Warren, W.G.; Boehm, M.; Link, D.

    1992-01-01

    A statistical methodology for exploring the relationships between elevation and precipitation chemistry is outlined and illustrated. The methodology utilizes maximum likelihood estimates and likelihood ratio tests with contour ellipses of assumed bivariate lognormal distributions used to assist in interpretation. The approach was illustrated using 12 NADP/NTN sites located in six study areas in the Wyoming and Colorado Rockies. These sites are part of the Rocky Mountain Deposition Monitoring Project (RMDMP), which was initiated in 1986 to investigate the relationships between elevation and the chemistry of precipitation. The results indicate differences in sulfate concentrations between airsheds, between snow and rain, and between higher and lower elevations. In general, sulfate concentrations in snow are greater at lower elevations and this difference is independent of concentration. A similar relationship for rain was not well established. In addition there is evidence that, overall, the sulfate concentrations differed between the six study areas, although pairwise differences were not always significant

  8. Protamine precipitation of two reovirus particle types from polluted waters.

    OpenAIRE

    Adams, D J; Ridinger, D N; Spendlove, R S; Barnett, B B

    1982-01-01

    Two forms of virus particle are released from reovirus-infected cell cultures, infectious reovirus and potentially infectious reovirus (PIV). PIV particle forms have a complete outer coat and are not infectious until the outer coat is altered or removed. The PIV concentration in polluted waters, however, has not been determined. Protamine sulfate precipitation, using 0.25% fetal bovine serum and 0.005% protamine sulfate for the first precipitation of the sample and 0.0025% for the second, was...

  9. The impacts of changing transport and precipitation on pollutant distributions in a future climate

    Science.gov (United States)

    Fang, Yuanyuan; Fiore, Arlene M.; Horowitz, Larry W.; Gnanadesikan, Anand; Held, Isaac; Chen, Gang; Vecchi, Gabriel; Levy, Hiram

    2011-09-01

    Air pollution (ozone and particulate matter in surface air) is strongly linked to synoptic weather and thus is likely sensitive to climate change. In order to isolate the responses of air pollutant transport and wet removal to a warming climate, we examine a simple carbon monoxide-like (CO) tracer (COt) and a soluble version (SAt), both with the 2001 CO emissions, in simulations with the Geophysical Fluid Dynamics Laboratory chemistry-climate model (AM3) for present (1981-2000) and future (2081-2100) climates. In 2081-2100, projected reductions in lower-tropospheric ventilation and wet deposition exacerbate surface air pollution as evidenced by higher surface COt and SAt concentrations. However, the average horizontal general circulation patterns in 2081-2100 are similar to 1981-2000, so the spatial distribution of COt changes little. Precipitation is an important factor controlling soluble pollutant wet removal, but the total global precipitation change alone does not necessarily indicate the sign of the soluble pollutant response to climate change. Over certain latitudinal bands, however, the annual wet deposition change can be explained mainly by the simulated changes in large-scale (LS) precipitation. In regions such as North America, differences in the seasonality of LS precipitation and tracer burdens contribute to an apparent inconsistency of changes in annual wet deposition versus annual precipitation. As a step toward an ultimate goal of developing a simple index that can be applied to infer changes in soluble pollutants directly from changes in precipitation fields as projected by physical climate models, we explore here a "Diagnosed Precipitation Impact" (DPI) index. This index captures the sign and magnitude (within 50%) of the relative annual mean changes in the global wet deposition of the soluble pollutant. DPI can only be usefully applied in climate models in which LS precipitation dominates wet deposition and horizontal transport patterns change

  10. Participation of the Pennsylvania State University in the MAP3S precipitation chemistry network

    International Nuclear Information System (INIS)

    Lamb, D.; de Pena, R.G.

    1991-04-01

    The Meteorology Department of the Pennsylvania State University collected precipitation in central Pennsylvania for more than 14 years on behalf of the Multistate Atmospheric Power Production Pollution Study (MAP3S). The MAP3S protocol, based on the sampling of precipitation from individual meteorological events over a long period of time, has allowed both for the development of a chemical climatology of precipitation in the eastern region of the United States and for a vastly improved understanding of the atmospheric processes responsible for wet acidic deposition. The precipitation chemistry data from the Penn State MAP3S site provide evidence of links to the anthropogenic emissions of sulfur dioxide and oxidant precursors. There is now little doubt that the free acidity in the precipitation of the region is due to the presence of unneutralized sulfate in the aqueous phase. In the absence of significant sources of this sulfur species and in view of supplemental enrichment studies, it is concluded that the sulfate enters cloud and rain water primarily through the aqueous-phase oxidation of sulfur dioxide emitted into the air within the geographical region of deposition. Within the source region the local abundances of sulfur dioxide often exceed those of the oxidants, so the depositions of sulfate and free acidity tend to be modulated by the availability of the strong oxidants. As a consequence, the deposition of sulfate exhibits a very strong seasonal dependence and little response to changes in the emissions of sulfur dioxide

  11. Particle precipitation: How the spectrum fit impacts atmospheric chemistry

    Science.gov (United States)

    Wissing, J. M.; Nieder, H.; Yakovchouk, O. S.; Sinnhuber, M.

    2016-11-01

    Particle precipitation causes atmospheric ionization. Modeled ionization rates are widely used in atmospheric chemistry/climate simulations of the upper atmosphere. As ionization rates are based on particle measurements some assumptions concerning the energy spectrum are required. While detectors measure particles binned into certain energy ranges only, the calculation of a ionization profile needs a fit for the whole energy spectrum. Therefore the following assumptions are needed: (a) fit function (e.g. power-law or Maxwellian), (b) energy range, (c) amount of segments in the spectral fit, (d) fixed or variable positions of intersections between these segments. The aim of this paper is to quantify the impact of different assumptions on ionization rates as well as their consequences for atmospheric chemistry modeling. As the assumptions about the particle spectrum are independent from the ionization model itself the results of this paper are not restricted to a single ionization model, even though the Atmospheric Ionization Module OSnabrück (AIMOS, Wissing and Kallenrode, 2009) is used here. We include protons only as this allows us to trace changes in the chemistry model directly back to the different assumptions without the need to interpret superposed ionization profiles. However, since every particle species requires a particle spectrum fit with the mentioned assumptions the results are generally applicable to all precipitating particles. The reader may argue that the selection of assumptions of the particle fit is of minor interest, but we would like to emphasize on this topic as it is a major, if not the main, source of discrepancies between different ionization models (and reality). Depending on the assumptions single ionization profiles may vary by a factor of 5, long-term calculations may show systematic over- or underestimation in specific altitudes and even for ideal setups the definition of the energy-range involves an intrinsic 25% uncertainty for the

  12. MAP3S Precipitation Chemistry Network: second periodic summary report, July 1977--June 1978

    Energy Technology Data Exchange (ETDEWEB)

    1979-01-01

    The MAP3S Precipitation Chemistry Network consists of eight sites located in the northeastern United States. Precipitation event samples are collected by cooperating site operators, using specially developed sampling equipment. The concentration data collected over the period July 1, 1977 to July 1, 1978, are listed as a summary of the data reported monthly throughout the year. Samples were chemically analyzed at a central laboratory for 13 pollutant species - pH, conductivity, SO/sub 2/, SO/sub 4//sup =/, NH/sub 4//sup +/, NO/sub 2//sup -/, NO/sub 3//sup -/, Cl/sup -/, PO/sub 4//sup 3 -/, Na/sup +/, K/sup +/, Ca/sup + +/, and Mg/sup + +/ - using ion chromatography, automated wet chemistry, atomic absorption spectrophotometry, and electrode techniques. Second-year developments included: the installation of refrigeration equipment in all Battelle collectors; the initiation of an externally administered quality control program; and use of ion chromatography for cation as well as anion species. Supplementary research efforts included a special collector comparison study at the Pennsylvania State site and further analysis of sulfite versus sulfate deposition.

  13. Solving vertical transport and chemistry in air pollution models

    NARCIS (Netherlands)

    Berkvens, P.J.F.; Bochev, M.A.; Krol, M.C.; Peters, W.; Verwer, J.G.; Chock, David P.; Carmichael, Gregory R.; Brick, Patricia

    2002-01-01

    For the time integration of stiff transport-chemistry problems from air pollution modelling, standard ODE solvers are not feasible due to the large number of species and the 3D nature. The popular alternative, standard operator splitting, introduces artificial transients for short-lived species.

  14. Solving Vertical Transport and Chemistry in Air Pollution Models

    NARCIS (Netherlands)

    Berkvens, P.J.F.; Bochev, M.A.; Verwer, J.G.; Krol, M.C.; Peters, W.

    For the time integration of stiff transport-chemistry problems from air pollution modelling, standard ODE solvers are not feasible due to the large number of species and the 3D nature. The popular alternative, standard operator splitting, introduces artificial transients for short-lived species.

  15. Inhibition and promotion of trace pollutant adsorption within electrostatic precipitators.

    Science.gov (United States)

    Clack, Herek L

    2017-08-01

    Among the technologies available for reducing mercury emissions from coal-fired electric utilities is the injection of a powdered sorbent, often some form of activated carbon, into the flue gas upstream of the particulate control device, most commonly an electrostatic precipitator (ESP). Detailed measurements of mercury removal within ESPs are lacking due to the hazardous environment they pose, increasing the importance of analysis and numerical simulation in understanding the mechanisms involved. Our previous analyses revealed that mercury adsorption by particles suspended in the gas and mercury adsorption by particles collected on internal ESP surfaces are not additive removal mechanisms but rather are competitive. The present study expands on this counterintuitive finding. Presented are results from numerical simulations reflecting the complete range of possible mass transfer boundary conditions representing mercury adsorption by the accumulated dust cake covering internal ESP collection electrodes. Using the two mercury removal mechanisms operating concurrently and interdependently always underperforms the sum of the two mechanisms' individual contributions. The dual use of electrostatic precipitators (ESPs) for particulate removal and adsorption of trace gaseous pollutants such as mercury is increasing as mercury regulations become more widespread. Under such circumstances, mercury adsorption by particles suspended in the gas and mercury adsorption by particles collected on internal ESP surfaces are competitive. Together, the two mercury removal mechanisms always underperform the sum of their two independent contributions. These findings can inform strategies sought by electric utilities for reducing the usage costs of mercury sorbents.

  16. Manual for the GAW Precipitation Chemistry Programme: Guidelines, Data Quality Objectives and Standard Operating Procedures

    National Research Council Canada - National Science Library

    Allan, Mary A

    2004-01-01

    This is a manual for the Global Atmosphere Watch Precipitation Chemistry (GAW-PC) Programme. Where possible, it describes standard operating procedures and otherwise provides guidance on methods and procedures...

  17. Influence of biomass burning emissions on precipitation chemistry in the equatorial forests of Africa

    International Nuclear Information System (INIS)

    Lacaux, J.P.; Lefeivre, B.; Delmas, R.A.; Cros, B.; Andreae, M.O.

    1991-01-01

    As part of the DESCAFE program (Dynamics and Chemistry of the Atmosphere in Equatorial Forest), measurements of precipitation chemistry were made at two sampling sites of the equatorial forest in the Republic of Congo. The measurements were made in order to identify and compare atmospheric sources of gases and particles (mainly biogenic sources and emissions from burning vegetation)

  18. Atmospheric and precipitation chemistry over the North Atlantic Ocean: Shipboard results, April-May 1984

    Science.gov (United States)

    Church, T. M.; Tramontano, J. M.; Whelpdale, D. M.; Andreae, M. O.; Galloway, J. N.; Keene, W. C.; Knap, A. H.; Tokos, J.

    1991-10-01

    During a North Atlantic cruise from Dakar, Senegal, to Woods Hole, Massachusetts (April 14-May 11, 1984), crossing the area of 14°-48°N; 17°-70°W, we collected atmospheric aerosols (C, N, S species), gases (SO4, HNO3, dimethyl sulfide (DMS), synthetic organic chemicals), and precipitation (major inorganic/organic ions, trace metals). Air masses that had not contacted land for over 5 days had a composition close to that from the remote marine atmosphere. Oxidation of biogenic DMS to SO4= aerosol accounted for most nss-SO4= in these air masses. Air masses that had transected densely populated North America (in the westerlies) or the Mediterranean/North Africa ( in the easterlies) within 2-5 days of being sampled over the North Atlantic were enriched in acid precursor compounds and synthetic hydrocarbons relative to air that had spent longer over the North Atlantic. Strong acids and trace metals were also elevated in precipitation. Air masses that had transected regions of strong emissions within the preceding 2 days had concentrations of atmospheric pollutants approaching those typically found in continental air masses. More frequent storm tracks between the Icelandic low and the Bermuda high favored transport of North American emissions northeasterly, toward Europe. Trajectory analyses suggested that air masses sampled off the northwest African coast had passed over the Mediterranean. Composition of the aerosol and precipitation of these air masses was also indicative of continental emissions, including biomass and petroleum burning. Transport and deposition of continental emissions to the North Atlantic were significantly influencing surface atmospheric and oceanic chemistry of this region.

  19. Physics and chemistry of plasma pollution control technology

    International Nuclear Information System (INIS)

    Chang, J S

    2008-01-01

    Gaseous pollution control technologies for acid gases (NO x , SO x , etc), volatile organic compounds, greenhouse gases, ozone layer depleting substances, etc have been commercialized based on catalysis, incineration and adsorption methods. However, non-thermal plasma techniques based on electron beams and corona discharges are becoming significant due to advantages such as lower costs, higher removal efficiency and smaller space volume. In order to commercialize this new technology, the pollution gas removal rate, energy efficiency of removal, pressure drop of reactors and useable by-product production rates must be improved and identification of major fundamental processes and optimizations of reactor and power supply for an integrated system must be investigated. In this work, the chemistry and physics of plasma pollution control are discussed and the limitation of this type of plasma is outlined based on the plasma parameters.

  20. Multivariate statistical analysis of precipitation chemistry in Northwestern Spain

    International Nuclear Information System (INIS)

    Prada-Sanchez, J.M.; Garcia-Jurado, I.; Gonzalez-Manteiga, W.; Fiestras-Janeiro, M.G.; Espada-Rios, M.I.; Lucas-Dominguez, T.

    1993-01-01

    149 samples of rainwater were collected in the proximity of a power station in northwestern Spain at three rainwater monitoring stations. The resulting data are analyzed using multivariate statistical techniques. Firstly, the Principal Component Analysis shows that there are three main sources of pollution in the area (a marine source, a rural source and an acid source). The impact from pollution from these sources on the immediate environment of the stations is studied using Factorial Discriminant Analysis. 8 refs., 7 figs., 11 tabs

  1. Multivariate statistical analysis of precipitation chemistry in Northwestern Spain

    Energy Technology Data Exchange (ETDEWEB)

    Prada-Sanchez, J.M.; Garcia-Jurado, I.; Gonzalez-Manteiga, W.; Fiestras-Janeiro, M.G.; Espada-Rios, M.I.; Lucas-Dominguez, T. (University of Santiago, Santiago (Spain). Faculty of Mathematics, Dept. of Statistics and Operations Research)

    1993-07-01

    149 samples of rainwater were collected in the proximity of a power station in northwestern Spain at three rainwater monitoring stations. The resulting data are analyzed using multivariate statistical techniques. Firstly, the Principal Component Analysis shows that there are three main sources of pollution in the area (a marine source, a rural source and an acid source). The impact from pollution from these sources on the immediate environment of the stations is studied using Factorial Discriminant Analysis. 8 refs., 7 figs., 11 tabs.

  2. Solving vertical transport and chemistry in air pollution models

    International Nuclear Information System (INIS)

    Berkvens, P.J.F.; Botchev, M.A.; Verwer, J.G.; Krol, M.C.; Peters, W.

    2000-01-01

    For the time integration of stiff transport-chemistry problems from air pollution modelling, standard ODE solvers are not feasible due to the large number of species and the 3D nature. The popular alternative, standard operator splitting, introduces artificial transients for short-lived species. This complicates the chemistry solution, easily causing large errors for such species. In the framework of an operational global air pollution model, we focus on the problem formed by chemistry and vertical transport, which is based on diffusion, cloud-related vertical winds, and wet deposition. Its specific nature leads to full Jacobian matrices, ruling out standard implicit integration. We compare Strang operator splitting with two alternatives: source splitting and an (unsplit) Rosenbrock method with approximate matrix factorization, all having equal computational cost. The comparison is performed with real data. All methods are applied with half-hour time steps, and give good accuracies. Rosenbrock is the most accurate, and source splitting is more accurate than Strang splitting. Splitting errors concentrate in short-lived species sensitive to solar radiation and species with strong emissions and depositions. 30 refs

  3. Fundamental chemistry of precipitation and mineral scale formation

    Science.gov (United States)

    Alan W. Rudie; Peter W. Hart

    2005-01-01

    The mineral scale that deposits in digesters and bleach plants is formed by a chemical precipitation process. As such, it is accurately described or modeled using the solubility product equilibrium constant. Although solubility product identifies the primary conditions that need to be met for a scale problem to exist, the acid base equilibria of the scaling anions...

  4. Potential alteration of precipitation chemistry by epiphytic lichens

    Energy Technology Data Exchange (ETDEWEB)

    Lang, G E; Reiners, W A; Heier, R K

    1976-01-01

    Epiphytic lichen growth is abundant on the boles and branches of balsam fir trees at high elevations in New Hampshire. These lichens absorb elements needed for growth from solutions flowing over their surfaces and from direct impaction of water droplets. This study describes how epiphytic lichens and fir needles altered the chemistry of simulated rain water solutions under laboratory conditions. Experiments showed: 1) lichens absorbed ammonium and nitrate from solution; the rate of uptake increased with increasing temperature of the solution, 2) lichens lost calcium, magnesium, and hydrogen to the solution, 3) lichen thalli also initially lost potassium, but in time, net movement was reversed back into the thallus, 4) cation movement increased with increasing temperature, and 5) fir needles responded in a manner similar to that of the lichens, but the amount of change was much less. From these results it seems that epiphytic lichens have potential ecological importance in altering the chemistry of throughfall and stemflow.

  5. Long range transport of air pollutants in Europe and acid precipitation in Norway

    Science.gov (United States)

    Jack Nordo

    1976-01-01

    Observations show that pollutants from large emission sources may cause significant air concentrations 500 to 1000 miles away. Very acid precipitation occurs in such periods. The scavenging is often intensified by the topography. Case studies will be presented, with special emphasis on acid precipitation in Scandinavia. Large scale dispersion models have been developed...

  6. Chemistry and isotopic composition of precipitation and surface waters in Khumbu valley (Nepal Himalaya): N dynamics of high elevation basins

    International Nuclear Information System (INIS)

    Balestrini, Raffaella; Polesello, Stefano; Sacchi, Elisa

    2014-01-01

    We monitored the chemical and isotopic compositions of wet depositions, at the Pyramid International Laboratory (5050 m a.s.l.), and surrounding surface waters, in the Khumbu basin, to understand precipitation chemistry and to obtain insights regarding ecosystem responses to atmospheric inputs. The major cations in the precipitation were NH 4 + and Ca 2+ , whereas the main anion was HCO 3 − , which constituted approximately 69% of the anions, followed by NO 3 − , SO 4 2− and Cl − . Data analysis suggested that Na + , Cl − and K + were derived from the long-range transport of marine aerosols. Ca 2+ , Mg 2+ and HCO 3 − were related to rock and soil dust contributions and the NO 3 − and SO 4 2− concentrations were derived from anthropogenic sources. Furthermore, NH 4 + was derived from gaseous NH 3 scavenging. The isotopic composition of weekly precipitation ranged from − 1.9 to − 23.2‰ in δ 18 O, and from − 0.8 to − 174‰ in δ 2 H, with depleted values characterizing the central part of the monsoon period. The chemical composition of the stream water was dominated by calcite and/or gypsum dissolution. However, the isotopic composition of the stream water did not fully reflect the composition of the monsoon precipitation, which suggested that other water sources contributed to the stream flow. Precipitation contents for all ions were the lowest ones among those measured in high elevation sites around the world. During the monsoon periods the depositions were not substantially influenced by anthropogenic inputs, while in pre- and post-monsoon seasons the Himalayas could not represent an effective barrier for airborne pollution. In the late monsoon phase, the increase of ionic contents in precipitation could also be due to a change in the moisture source. The calculated atmospheric N load (0.30 kg ha −1 y −1 ) was considerably lower than the levels that were measured in other high-altitude environments. Nevertheless, the NO 3

  7. An Analysis of Undergraduate General Chemistry Students' Misconceptions of the Submicroscopic Level of Precipitation Reactions

    Science.gov (United States)

    Kelly, Resa M.; Barrera, Juliet H.; Mohamed, Saheed C.

    2010-01-01

    This study examined how 21 college-level general chemistry students, who had received instruction that emphasized the symbolic level of ionic equations, explained their submicroscopic-level understanding of precipitation reactions. Students' explanations expressed through drawings and semistructured interviews revealed the nature of the…

  8. Relationships between precipitation and surface water chemistry in three Carolina bays

    International Nuclear Information System (INIS)

    Monegue, R.L.; Jagoe, C.H.

    1995-01-01

    Carolina Bays are shallow freshwater wetlands, the only naturally occurring lentic systems on the southeastern coastal plain. Bays are breeding sites for many amphibian species, but data on precipitation/surface water relationships and long-term chemical trends are lacking. Such data are essential to interpret major fluctuations in amphibian populations. Surface water and bulk precipitation were sampled bi-weekly for over two years at three bays along a 25 km transect on the Savannah River Site in South Carolina. Precipitation chemistry was similar at all sites; average pH was 4.56, and the major ions were H + (30.8 % of total), and SO 4 (50.3% of total). H + was positively correlated with SO 4 , suggesting the importance of anthropogenic acids to precipitation chemistry. All three bays, Rainbow Bay (RB), Thunder Bay (TB), and Ellenton Bay (EB), contained soft (specific conductivity 5--90 microS/cm), acidic water (pH 4.0--5.9) with DOM from 4--40 mg/L. The major cation for RB, TB, and EB, respectively, was: Mg (30.8 % of total); Na (27% of total); and Ca (34.2% of total). DOM was the major anion for all bays, and SO 4 represented 13 to 28 % of total anions. H + was not correlated to DOM or SO, in RB; H + was positively correlated to DOM and SO 4 in TB, and negatively correlated to DOM and SO 4 in EB. Different biogeochemical processes probably control pH and other chemical variables in each bay. While surface water H + was not directly correlated with precipitation H + , NO 3 , or SO 4 , precipitation and shallow groundwater are dominant water sources for these bays. Atmospheric inputs of anthropogenic acids and other chemicals are important factors influencing bay chemistry

  9. Fog and precipitation chemistry at a mid-land forest in central Taiwan.

    Science.gov (United States)

    Liang, Yang-Ling; Lin, Teng-Chiu; Hwong, Jeen-Liang; Lin, Neng-Huei; Wang, Chiao-Ping

    2009-01-01

    We analyzed fog and bulk precipitation chemistry at a cloud forest in central Taiwan where mountain agriculture activities are highest. There were 320 foggy days (visibility agriculture has a major impact on atmospheric deposition at the surrounding forest ecosystems. The input of inorganic N reached 125 kg N ha(-1) yr(-1) and likely exceeded the biological demand of the forest ecosystem. Sulfate is the most abundant anion in fog at Chi-tou and in precipitation at various forests throughout Taiwan, suggesting that the emission and transport of large quantities of SO(2,) the precursor of SO(4)(2-), is an island-wide environmental issue.

  10. Sampling of Atmospheric Precipitation and Deposits for Analysis of Atmospheric Pollution

    OpenAIRE

    Skarżyńska, K.; Polkowska, Ż; Namieśnik, J.

    2006-01-01

    This paper reviews techniques and equipment for collecting precipitation samples from the atmosphere (fog and cloud water) and from atmospheric deposits (dew, hoarfrost, and rime) that are suitable for the evaluation of atmospheric pollution. It discusses the storage and preparation of samples for analysis and also presents bibliographic information on the concentration ranges of inorganic and organic compounds in the precipitation and atmospheric deposit samples.

  11. Changes in precipitating snow chemistry with seasonality in the remote Laohugou glacier basin, western Qilian Mountains.

    Science.gov (United States)

    Dong, Zhiwen; Qin, Dahe; Qin, Xiang; Cui, Jianyong; Kang, Shichang

    2017-04-01

    Trace elements in the atmosphere could provide information about regional atmospheric pollution. This study presented a whole year of precipitation observation data regarding the concentrations of trace metals (e.g., Cr, Ni, Cu, Mn, Cd, Mo, Pb, Sb, Ti, and Zn), and a TEM-EDX (transmission electron microscope-energy dispersive X-ray spectrometer) analysis from June 2014 to September 2015 at a remote alpine glacier basin in Northwest China, the Laohugou (LHG) basin (4200 m a.s.l.), to determine the regional scale of atmospheric conditions and chemical processing in the free troposphere in the region. The results of the concentrations of trace metals showed that, although the concentrations generally were lower compared with that of surrounding rural areas (and cities), they showed an obviously higher concentration and higher EFs in winter (DJF) and a relatively lower concentration and lower EFs in summer (JJA) and autumn (SON), implying clearly enhanced winter pollution of the regional atmosphere in Northwest China. The TEM observed residue in precipitation that was mainly composed of types of dust, salt-dust, BC-fly ash-soot, and organic particles in precipitation, which also showed remarked seasonal change, showing an especially high ratio of BC-soot-fly ash particles in winter precipitation compared with that of other seasons (while organic particles were higher in the summer), indicating significant increased anthropogenic particles in the winter atmosphere. The source of increased winter anthropogenic pollutants mainly originated from emissions from coal combustion, e.g., the regional winter heating supply for residents and cement factories in urban and rural regions of Northwest China. Moderate Resolution Imaging Spectroradiometer (MODIS) atmospheric optical depth (AOD) also showed a significant influence of regional atmospheric pollutant emissions over the region in winter. In total, this work indicated that the atmospheric environment in western Qilian

  12. Chemistry and isotopic composition of precipitation and surface waters in Khumbu valley (Nepal Himalaya): N dynamics of high elevation basins.

    Science.gov (United States)

    Balestrini, Raffaella; Polesello, Stefano; Sacchi, Elisa

    2014-07-01

    We monitored the chemical and isotopic compositions of wet depositions, at the Pyramid International Laboratory (5050 ma.s.l.), and surrounding surface waters, in the Khumbu basin, to understand precipitation chemistry and to obtain insights regarding ecosystem responses to atmospheric inputs. The major cations in the precipitation were NH4(+) and Ca(2+), whereas the main anion was HCO3(-), which constituted approximately 69% of the anions, followed by NO3(-), SO4(2-) and Cl(-). Data analysis suggested that Na(+), Cl(-) and K(+) were derived from the long-range transport of marine aerosols. Ca(2+), Mg(2+) and HCO3(-) were related to rock and soil dust contributions and the NO3(-) and SO4(2-) concentrations were derived from anthropogenic sources. Furthermore, NH4(+) was derived from gaseous NH3 scavenging. The isotopic composition of weekly precipitation ranged from -1.9 to -23.2‰ in δ(18)O, and from -0.8 to -174‰ in δ(2)H, with depleted values characterizing the central part of the monsoon period. The chemical composition of the stream water was dominated by calcite and/or gypsum dissolution. However, the isotopic composition of the stream water did not fully reflect the composition of the monsoon precipitation, which suggested that other water sources contributed to the stream flow. Precipitation contents for all ions were the lowest ones among those measured in high elevation sites around the world. During the monsoon periods the depositions were not substantially influenced by anthropogenic inputs, while in pre- and post-monsoon seasons the Himalayas could not represent an effective barrier for airborne pollution. In the late monsoon phase, the increase of ionic contents in precipitation could also be due to a change in the moisture source. The calculated atmospheric N load (0.30 kg ha(-1) y(-1)) was considerably lower than the levels that were measured in other high-altitude environments. Nevertheless, the NO3(-) concentrations in the surface waters

  13. Chemistry and isotopic composition of precipitation and surface waters in Khumbu valley (Nepal Himalaya): N dynamics of high elevation basins

    Energy Technology Data Exchange (ETDEWEB)

    Balestrini, Raffaella, E-mail: balestrini@irsa.cnr.it [Water Research Institute, National Research Council (IRSA-CNR), Via del Mulino 19, Brugherio, MB (Italy); Polesello, Stefano [Water Research Institute, National Research Council (IRSA-CNR), Via del Mulino 19, Brugherio, MB (Italy); Sacchi, Elisa [Department of Earth and Environmental Sciences, University of Pavia and IGG-CNR, Via Ferrata 1, 27100 Pavia (Italy)

    2014-07-01

    We monitored the chemical and isotopic compositions of wet depositions, at the Pyramid International Laboratory (5050 m a.s.l.), and surrounding surface waters, in the Khumbu basin, to understand precipitation chemistry and to obtain insights regarding ecosystem responses to atmospheric inputs. The major cations in the precipitation were NH{sub 4}{sup +} and Ca{sup 2+}, whereas the main anion was HCO{sub 3}{sup −}, which constituted approximately 69% of the anions, followed by NO{sub 3}{sup −}, SO{sub 4}{sup 2−} and Cl{sup −}. Data analysis suggested that Na{sup +}, Cl{sup −} and K{sup +} were derived from the long-range transport of marine aerosols. Ca{sup 2+}, Mg{sup 2+} and HCO{sub 3}{sup −} were related to rock and soil dust contributions and the NO{sub 3}{sup −} and SO{sub 4}{sup 2−} concentrations were derived from anthropogenic sources. Furthermore, NH{sub 4}{sup +} was derived from gaseous NH{sub 3} scavenging. The isotopic composition of weekly precipitation ranged from − 1.9 to − 23.2‰ in δ{sup 18}O, and from − 0.8 to − 174‰ in δ{sup 2}H, with depleted values characterizing the central part of the monsoon period. The chemical composition of the stream water was dominated by calcite and/or gypsum dissolution. However, the isotopic composition of the stream water did not fully reflect the composition of the monsoon precipitation, which suggested that other water sources contributed to the stream flow. Precipitation contents for all ions were the lowest ones among those measured in high elevation sites around the world. During the monsoon periods the depositions were not substantially influenced by anthropogenic inputs, while in pre- and post-monsoon seasons the Himalayas could not represent an effective barrier for airborne pollution. In the late monsoon phase, the increase of ionic contents in precipitation could also be due to a change in the moisture source. The calculated atmospheric N load (0.30 kg ha{sup −1} y{sup −1

  14. Chemistry and the Internal Combustion Engine II: Pollution Problems.

    Science.gov (United States)

    Hunt, C. B.

    1979-01-01

    Discusses pollution problems which arise from the use of internal combustion (IC) engines in the United Kingdom (UK). The IC engine exhaust emissions, controlling IC engine pollution in the UK, and some future developments are also included. (HM)

  15. Nonlinear regression and ARIMA models for precipitation chemistry in East Central Florida from 1978 to 1997

    International Nuclear Information System (INIS)

    Nickerson, David M.; Madsen, Brooks C.

    2005-01-01

    Continuous monitoring of precipitation in East Central Florida has occurred since 1978 at a sampling site located on the University of Central Florida (UCF) campus. Monthly volume-weighted average (VWA) concentration for several major analytes that are present in precipitation samples was calculated from samples collected daily. Monthly VWA concentration and wet deposition of H + , NH 4 + , Ca 2+ , Mg 2+ , NO 3 - , Cl - and SO 4 2- were evaluated by a nonlinear regression (NLR) model that considered 10-year data (from 1978 to 1987) and 20-year data (from 1978 to 1997). Little change in the NLR parameter estimates was indicated among the 10-year and 20-year evaluations except for general decreases in the predicted trends from the 10-year to the 20-year fits. Box-Jenkins autoregressive integrated moving average (ARIMA) models with linear trend were considered as an alternative to the NLR models for these data. The NLR and ARIMA model forecasts for 1998 were compared to the actual 1998 data. For monthly VWA concentration values, the two models gave similar results. For the wet deposition values, the ARIMA models performed considerably better. - Autoregressive integrated moving average models of precipitation data are an improvement over nonlinear models for the prediction of precipitation chemistry composition

  16. Atmospheric chemistry and physics from air pollution to climate change

    CERN Document Server

    Seinfeld, John H

    2016-01-01

    Expanded and updated with new findings and new features Since the second edition of Seinfeld and Pandis’ classic textbook, significant progress has taken place in the field of atmospheric chemistry and physics, particularly in the areas of tropospheric chemistry, aerosols, and the science of climate change. A new edition of this comprehensive work has been developed by the renowned author team. Atmospheric Chemistry and Physics, 3rd Edition, as the previous two editions have done, provides a rigorous and comprehensive treatment of the chemistry and physics of the atmosphere – including the chemistry of the stratosphere and troposphere, aerosol physics and chemistry, atmospheric new particle formation, physical meteorology, cloud physics, global climate, statistical analysis of data, and mathematical chemical/transport models of the atmosphere. Each of these topics is covered in detail and in each area the central results are developed from first principles. In this way the reader gains a significant un...

  17. Aerosol and precipitation chemistry in the southwestern United States: spatiotemporal trends and interrelationships

    Science.gov (United States)

    Sorooshian, A.; Shingler, T.; Harpold, A.; Feagles, C. W.; Meixner, T.; Brooks, P. D.

    2013-08-01

    This study characterizes the spatial and temporal patterns of aerosol and precipitation composition at six sites across the United States Southwest between 1995 and 2010. Precipitation accumulation occurs mostly during the wintertime (December-February) and during the monsoon season (July-September). Rain and snow pH levels are usually between 5-6, with crustal-derived species playing a major role in acid neutralization. These species (Ca2+, Mg2+, K+, Na+) exhibit their highest concentrations between March and June in both PM2.5 and precipitation due mostly to dust. Crustal-derived species concentrations in precipitation exhibit positive relationships with SO42-, NO3-, and Cl-, suggesting that acidic gases likely react with and partition to either crustal particles or hydrometeors enriched with crustal constituents. Concentrations of particulate SO42- show a statistically significant correlation with rain SO42- unlike snow SO42-, which may be related to some combination of the vertical distribution of SO42- (and precursors) and the varying degree to which SO42--enriched particles act as cloud condensation nuclei versus ice nuclei in the region. The coarse : fine aerosol mass ratio was correlated with crustal species concentrations in snow unlike rain, suggestive of a preferential role of coarse particles (mainly dust) as ice nuclei in the region. Precipitation NO3- : SO42- ratios exhibit the following features with potential explanations discussed: (i) they are higher in precipitation as compared to PM2.5; (ii) they exhibit the opposite annual cycle compared to particulate NO3- : SO42- ratios; and (iii) they are higher in snow relative to rain during the wintertime. Long-term trend analysis for the monsoon season shows that the NO3- : SO42- ratio in rain increased at the majority of sites due mostly to air pollution regulations of SO42- precursors.

  18. Aerosol and precipitation chemistry in the southwestern United States: spatiotemporal trends and interrelationships

    Science.gov (United States)

    Sorooshian, A.; Shingler, T.; Harpold, A.; Feagles, C. W.; Meixner, T.; Brooks, P. D.

    2013-01-01

    This study characterizes the spatial and temporal patterns of aerosol and precipitation composition at six sites across the United States Southwest between 1995 and 2010. Precipitation accumulation occurs mostly during the wintertime (December–February) and during the monsoon season (July–September). Rain and snow pH levels are usually between 5–6, with crustal-derived species playing a major role in acid neutralization. These species (Ca2+, Mg2+, K+, Na+) exhibit their highest concentrations between March and June in both PM2.5 and precipitation due mostly to dust. Crustal-derived species concentrations in precipitation exhibit positive relationships with SO42−, NO3−, and Cl–, suggesting that acidic gases likely react with and partition to either crustal particles or hydrometeors enriched with crustal constituents. Concentrations of particulate SO42− show a statistically significant correlation with rain SO42− unlike snow SO42−, which may be related to some combination of the vertical distribution of SO42− (and precursors) and the varying degree to which SO42−-enriched particles act as cloud condensation nuclei versus ice nuclei in the region. The coarse : fine aerosol mass ratio was correlated with crustal species concentrations in snow unlike rain, suggestive of a preferential role of coarse particles (mainly dust) as ice nuclei in the region. Precipitation NO3− : SO42− ratios exhibit the following features with potential explanations discussed: (i) they are higher in precipitation as compared to PM2.5; (ii) they exhibit the opposite annual cycle compared to particulate NO3− : SO42− ratios; and (iii) they are higher in snow relative to rain during the wintertime. Long-term trend analysis for the monsoon season shows that the NO3− : SO42− ratio in rain increased at the majority of sites due mostly to air pollution regulations of SO42− precursors. PMID:24432030

  19. Aerosol and precipitation chemistry in the southwestern United States: spatiotemporal trends and interrelationships

    Directory of Open Access Journals (Sweden)

    A. Sorooshian

    2013-08-01

    Full Text Available This study characterizes the spatial and temporal patterns of aerosol and precipitation composition at six sites across the United States Southwest between 1995 and 2010. Precipitation accumulation occurs mostly during the wintertime (December–February and during the monsoon season (July–September. Rain and snow pH levels are usually between 5–6, with crustal-derived species playing a major role in acid neutralization. These species (Ca2+, Mg2+, K+, Na+ exhibit their highest concentrations between March and June in both PM2.5 and precipitation due mostly to dust. Crustal-derived species concentrations in precipitation exhibit positive relationships with SO42−, NO3−, and Cl−, suggesting that acidic gases likely react with and partition to either crustal particles or hydrometeors enriched with crustal constituents. Concentrations of particulate SO42− show a statistically significant correlation with rain SO42− unlike snow SO42−, which may be related to some combination of the vertical distribution of SO42− (and precursors and the varying degree to which SO42−-enriched particles act as cloud condensation nuclei versus ice nuclei in the region. The coarse : fine aerosol mass ratio was correlated with crustal species concentrations in snow unlike rain, suggestive of a preferential role of coarse particles (mainly dust as ice nuclei in the region. Precipitation NO3− : SO42− ratios exhibit the following features with potential explanations discussed: (i they are higher in precipitation as compared to PM2.5; (ii they exhibit the opposite annual cycle compared to particulate NO3− : SO42− ratios; and (iii they are higher in snow relative to rain during the wintertime. Long-term trend analysis for the monsoon season shows that the NO3− : SO42− ratio in rain increased at the majority of sites due mostly to air pollution regulations of SO42− precursors.

  20. Spatial and temporal variability of precipitation and chemistry: Case studies from the Frontal Boundary Study

    International Nuclear Information System (INIS)

    Dana, M.T.

    1993-01-01

    Regional and larger-scale models of pollutant transport and deposition generally, by practical necessity, must be limited in output of precipitation rate and chemical composition to values for selected time intervals representing areas on the order of 10 4 km 2 . Naturally, it is of some concern that these values be reasonably representative of natural variations both in time and space. This question may be approached through field studies involving detailed spatial (using a network of samplers on the model grid scale) and temporal (using sequential sampling) measurements. This paper presents an initial analysis, using simple statistical concepts, of data bases from such a field study, the Frontal Boundary Study (FBS)

  1. Air pollution or global warming: Attribution of extreme precipitation changes in eastern China—Comments on "Trends of extreme precipitation in Eastern China and their possible causes"

    Science.gov (United States)

    Wang, Yuan

    2015-10-01

    The recent study "Trends of Extreme Precipitation in Eastern China and Their Possible Causes" attributed the observed decrease/increase of light/heavy precipitation in eastern China to global warming rather than the regional aerosol effects. However, there exist compelling evidence from previous long-term observations and numerical modeling studies, suggesting that anthropogenic pollution is closely linked to the recent changes in precipitation intensity because of considerably modulated cloud physical properties by aerosols in eastern China. Clearly, a quantitative assessment of the aerosol and greenhouse effects on the regional scale is required to identify the primary cause for the extreme precipitation changes.

  2. Marine chemistry of energy-related pollutants. Iron-55 phenomenon

    International Nuclear Information System (INIS)

    Crecelius, E.A.; Robertson, D.E.; Abel, K.H.

    1981-01-01

    These programs are designed to increase understanding of the biogeochemical and physical processes that control the fate of energy-generated pollutants that enter the marine environment. This research provides an understanding of (1) the natural origins, distributions and concentrations in baseline data of trace metals and other contaminants in the oceans; (2) the input rates and mixing rates of pollutants introduced to the oceans; (3) the behavior and fate of the anthropogenic pollutants entering the oceans from the atmosphere and the continents; and (4) provides an assessment of the potential environmental impact of energy-generated pollutants on the marine environment

  3. The contribution of site to washout and rainout: Precipitation chemistry based on sample analysis from 0.5 mm precipitation increments and numerical simulation

    Science.gov (United States)

    Aikawa, Masahide; Kajino, Mizuo; Hiraki, Takatoshi; Mukai, Hitoshi

    2014-10-01

    Datasets of precipitation chemistry at a precipitation resolution of 0.5 mm from three sites were studied to determine whether the washout and rainout mechanisms differed with site type (urban, suburban, rural). Rainout accounted for approximately one-third of the total NO3- deposition and washout contributed two-thirds, irrespective of the site type, although the washout contribution at the urban site (over 70%) was larger than that at the other two sites. The rainout mechanism and the washout mechanism both accounted for about half the total SO42- deposition at the suburban and rural sites, whereas at the urban site the rainout contribution was over 80%. A chemical transport model produced similar levels of washout and rainout contributions as the precipitation chemistry data.

  4. Interpolating precipitation and its relation to runoff and non-point source pollution.

    Science.gov (United States)

    Chang, Chia-Ling; Lo, Shang-Lien; Yu, Shaw-L

    2005-01-01

    When rainfall spatially varies, complete rainfall data for each region with different rainfall characteristics are very important. Numerous interpolation methods have been developed for estimating unknown spatial characteristics. However, no interpolation method is suitable for all circumstances. In this study, several methods, including the arithmetic average method, the Thiessen Polygons method, the traditional inverse distance method, and the modified inverse distance method, were used to interpolate precipitation. The modified inverse distance method considers not only horizontal distances but also differences between the elevations of the region with no rainfall records and of its surrounding rainfall stations. The results show that when the spatial variation of rainfall is strong, choosing a suitable interpolation method is very important. If the rainfall is uniform, the precipitation estimated using any interpolation method would be quite close to the actual precipitation. When rainfall is heavy in locations with high elevation, the rainfall changes with the elevation. In this situation, the modified inverse distance method is much more effective than any other method discussed herein for estimating the rainfall input for WinVAST to estimate runoff and non-point source pollution (NPSP). When the spatial variation of rainfall is random, regardless of the interpolation method used to yield rainfall input, the estimation errors of runoff and NPSP are large. Moreover, the relationship between the relative error of the predicted runoff and predicted pollutant loading of SS is high. However, the pollutant concentration is affected by both runoff and pollutant export, so the relationship between the relative error of the predicted runoff and the predicted pollutant concentration of SS may be unstable.

  5. Virtually going green: The role of quantum computational chemistry in reducing pollution and toxicity in chemistry

    Science.gov (United States)

    Stevens, Jonathan

    2017-07-01

    Continuing advances in computational chemistry has permitted quantum mechanical calculation to assist in research in green chemistry and to contribute to the greening of chemical practice. Presented here are recent examples illustrating the contribution of computational quantum chemistry to green chemistry, including the possibility of using computation as a green alternative to experiments, but also illustrating contributions to greener catalysis and the search for greener solvents. Examples of applications of computation to ambitious projects for green synthetic chemistry using carbon dioxide are also presented.

  6. Combustion chemistry and formation of pollutants; Chimie de la combustion et formation des polluants

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    This book of proceedings reports on 7 papers on combustion chemistry and formation of pollutants presented during the workshop organized by the `Combustion and Flames` section of the French society of thermal engineers. The chemistry of combustion is analyzed in various situations such as: turbojet engines, spark ignition engines, industrial burners, gas turbines etc... Numerical simulation is used to understand the physico-chemical processes involved in combustion, to describe the kinetics of oxidation, combustion and flame propagation, and to predict the formation of pollutants. (J.S.)

  7. The response of a simulated mesoscale convective system to increased aerosol pollution: Part I: Precipitation intensity, distribution, and efficiency

    Science.gov (United States)

    Clavner, Michal; Cotton, William R.; van den Heever, Susan C.; Saleeby, Stephen M.; Pierce, Jeffery R.

    2018-01-01

    Mesoscale Convective Systems (MCSs) are important contributors to rainfall in the High Plains of the United States and elsewhere in the world. It is therefore of interest to understand how different aerosols serving as cloud condensation nuclei (CCN) may impact the total amount, rates and spatial distribution of precipitation produced by MCSs. In this study, different aerosol concentrations and their effects on precipitation produced by an MCS are examined by simulating the 8 May 2009 "Super-Derecho" MCS using the Regional Atmospheric Modeling System (RAMS), a cloud-resolving model (CRM) with sophisticated aerosol and microphysical parameterizations. Three simulations were conducted that differed only in the initial concentration, spatial distribution, and chemical composition of aerosols. Aerosol fields were derived from the output of GEOS-Chem, a 3D chemical transport numerical model. Results from the RAMS simulations show that the total domain precipitation was not significantly affected by variations in aerosol concentrations, however, the pollution aerosols altered the precipitation characteristics. The more polluted simulations exhibited higher precipitation rates, higher bulk precipitation efficiency, a larger area with heavier precipitation, and a smaller area with lighter precipitation. These differences arose as a result of aerosols enhancing precipitation in the convective region of the MCS while suppressing precipitation from the MCS's stratiform-anvil. In the convective region, several processes likely contributed to an increase of precipitation. First, owing to the very humid environment of this storm, the enhanced amount of cloud water available to be collected overwhelmed the reduction in precipitation efficiency associated with the aerosol-induced production of smaller droplets which led to a net increase in the conversion of cloud droplets to precipitation. Second, higher aerosol concentrations led to invigoration of convective updrafts which

  8. Precipitation effects on microbial pollution in a river: lag structures and seasonal effect modification.

    Directory of Open Access Journals (Sweden)

    Andreas Tornevi

    Full Text Available BACKGROUND: The river Göta Älv is a source of freshwater for 0.7 million swedes. The river is subject to contamination from sewer systems discharge and runoff from agricultural lands. Climate models projects an increase in precipitation and heavy rainfall in this region. This study aimed to determine how daily rainfall causes variation in indicators of pathogen loads, to increase knowledge of variations in river water quality and discuss implications for risk management. METHODS: Data covering 7 years of daily monitoring of river water turbidity and concentrations of E. coli, Clostridium and coliforms were obtained, and their short-term variations in relation with precipitation were analyzed with time series regression and non-linear distributed lag models. We studied how precipitation effects varied with season and compared different weather stations for predictive ability. RESULTS: Generally, the lowest raw water quality occurs 2 days after rainfall, with poor raw water quality continuing for several more days. A rainfall event of >15 mm/24-h (local 95 percentile was associated with a three-fold higher concentration of E. coli and 30% higher turbidity levels (lag 2. Rainfall was associated with exponential increases in concentrations of indicator bacteria while the effect on turbidity attenuated with very heavy rainfall. Clear associations were also observed between consecutive days of wet weather and decreased water quality. The precipitation effect on increased levels of indicator bacteria was significant in all seasons. CONCLUSIONS: Rainfall elevates microbial risks year-round in this river and freshwater source and acts as the main driver of varying water quality. Heavy rainfall appears to be a better predictor of fecal pollution than water turbidity. An increase of wet weather and extreme events with climate change will lower river water quality even more, indicating greater challenges for drinking water producers, and suggesting better

  9. Dendroecological applications in air pollution and environmental chemistry: research needs

    Science.gov (United States)

    Samuel B. McLaughlin; Walter C. Shortle; Kevin T. Smith

    2002-01-01

    During the past two decades, dendrochronology has evolved in new dimensions that have helped address both the extent and causes of impacts of regional scale environmental pollution on the productivity and function of forest ecosystems. Initial focus on the magnitude and timing of alterations of baseline growth levels of individual forest trees has now broadened to...

  10. Applications of neutron activation analysis in chemistry and pollution fields

    International Nuclear Information System (INIS)

    May, S.

    1978-01-01

    Some examples of applications of activation analysis are given such as: chemical analysis of precious metals, nuclear graphite and hydrocarbons; control of pollution of water and seawater, analysis of food and seafood, atmospheric, dust and hair for determination of impurities [fr

  11. Long term precipitation chemistry and wet deposition in a remote dry savanna site in Africa (Niger

    Directory of Open Access Journals (Sweden)

    C. Galy-Lacaux

    2009-03-01

    Full Text Available Long-term precipitation chemistry have been recorded in the rural area of Banizoumbou (Niger, representative of a semi-arid savanna ecosystem. A total of 305 rainfall samples ~90% of the total annual rainfall were collected from June 1994 to September 2005. From ionic chromatography, pH major inorganic and organic ions were detected. Rainwater chemistry is controlled by soil/dust emissions associated with terrigeneous elements represented by SO42−, Ca2+, Carbonates, K+ and Mg2+. It is found that calcium and carbonates represent ~40% of the total ionic charge. The second highest contribution is nitrogenous, with annual Volume Weighed Mean (VWM for NO3 and NH4+ concentrations of 11.6 and 18.1 μeq.l−1, respectively. This is the signature of ammonia sources from animals and NOx emissions from savannas soil-particles rain-induced. The mean annual NH3 and NO2 air concentration are of 6 ppbv and 2.6 ppbv, respectively. The annual VWM precipitation concentration of sodium and chloride are both of 8.7 μeq.l−1 which reflects the marine signature of monsoonal and humid air masses. The median pH value is of 6.05. Acidity is neutralized by mineral dust, mainly carbonates, and/or dissolved gases such NH3. High level of organic acidity with 8μeq.l−1 and 5.2 μeq.l−1 of formate and acetate were also found. The analysis of monthly Black Carbon emissions and Fraction of Absorbed Photosynthetically Active Radiation (FAPAR values show that both biogenic emission from vegetation and biomass burning could explain the rainfall organic acidity content. The interannual variability of the VWM concentrations around the mean (1994–2005 is between ±5% and ±30% and mainly due to variations of sources strength and rainfall spatio-temporal distribution. From 1994 to 2005

  12. HOW AGRICULTURAL CHEMISTRY CAN CONTRIBUTE TO DEALING WITH PROBLEMS OF ENVIRONMENTAL POLLUTION

    Directory of Open Access Journals (Sweden)

    Carlo Emanuele Gessa

    2010-08-01

    Full Text Available Soil is a complex heterogeneous system whose physical, chemical and biological properties regulate interactions with the chemical species which reach its surface. Soil chemistry is an essential tool for understanding and predicting these interactions. Soil is able to immobilize and transform organic and inorganic molecules by different mechanisms, such as complexing and redox reactions. This behaviour gives soil detoxifying capacities towards pollutants which accumulate in the environment. Pollution by heavy metals is regulated by their solubility in soil solution which in turn depends on soil pH and redox properties and metal speciation. Organic and inorganic colloidal soil fractions can promote the immobilisation, degradation, and diffusion of organic molecules such as agrochemicals, solvents, hydrocarbons and other chemicals which reach the soil by anthropic activities. Predicting the fate of xenobiotics in soil, water, air, and plant ecosystems, the recycling of biomass and the decontamination of polluted soils are of major concern to soil chemistry.

  13. Seasonal change in precipitation, snowpack, snowmelt, soil water and streamwater chemistry, northern Michigan

    Science.gov (United States)

    Stottlemyer, R.; Toczydlowski, D.

    1999-01-01

    We have studied weekly precipitation, snowpack, snowmelt, soil water and streamwater chemistry throughout winter for over a decade in a small (176 ha) northern Michigan watershed with high snowfall and vegetated by 60 to 80 year-old northern hardwoods. In this paper, we examine physical, chemical, and biological processes responsible for observed seasonal change in streamwater chemistry based upon intensive study during winter 1996-1997. The objective was to define the contributions made to winter and spring streamwater chemical concentration and flux by processes as snowmelt, over-winter forest floor and surface soil mineralization, immobilization, and exchange, and subsurface flowpath. The forest floor and soil were unfrozen beneath the snowpack which permitted most snowmelt to enter. Over-winter soil mineralization and other biological processes maintain shallow subsurface ion and dissolved organic carbon (DOC) reservoirs. Small, but steady, snowmelt throughout winter removed readily mobilized soil NO3- which resulted in high over-winter streamwater concentrations but little flux. Winter soil water levels and flowpaths were generally deep which increased soil water and streamwater base cation (C(B)), HCO3-, and Si concentrations. Spring snowmelt increased soil water levels and removal of ions and DOC from the biologically active forest floor and shallow soils. The snowpack solute content was a minor component in determining streamwater ion concentration or flux during and following peak snowmelt. Exchangeable ions, weakly adsorbed anions, and DOC in the forest floor and surface soils dominated the chemical concentration and flux in soil water and streamwater. Following peak snowmelt, soil microbial immobilization and rapidly increased plant uptake of limiting nutrients removed nearly all available nitrogen from soil water and streamwater. During the growing season high evapotranspiration increased subsurface flowpath depth which in turn removed weathering

  14. A hands-on approach to teaching environmental awareness and pollutant remediation to undergraduate chemistry students

    Science.gov (United States)

    Salman Ashraf, S.; Rauf, M. A.; Abdullah, Fatema H.

    2012-07-01

    Background : One of the unfortunate side effects of the industrial revolution has been the constant assault of the environment with various forms of pollution. Lately, this issue has taken a more critical dimension as prospects of global climate change and irreversible ecosystem damage are becoming a reality. Purpose : College graduates (especially chemists), should therefore not only be aware of these issues but also be taught how chemistry can help reduce environmental pollution. Furthermore, the role and importance of chemistry in sustainable development and solving environmental problems needs to be highlighted. Programme/intervention description : To this effect, we have designed a simple undergraduate experiment that is based on the green chemistry approach of using photolytic oxidation to degrade a model organic pollutant. This approach used UV light and hydrogen peroxide to produce reactive hydroxyl radicals, which subsequently break down and degrade Acridine Orange (model pollutant). The dye degradation was monitored spectrophotometrically and the apparent rate of decolouration was found to be first order. Possible radical initiated mechanisms that may be involved in this remediation experiment have been used to explain the observed dye decolouration. Sample : To test the usefulness of this newly developed experiment, we incorporated it as a module into a second year 'Professional skills' chemistry course with an enrollment of six female students. Anonymous survey of the students after the completion of the module was very positive and indicated that objectives of the experiment were satisfactorily achieved. Results : We believe this experiment not only raises students' awareness about green chemistry and environmental issues, but also teaches them valuable experimental skills such as experimental design, data manipulation and basic kinetics. Survey of students who were taught this unit in a second year course was very positive and supported the usefulness

  15. The use of geoinformatic data and spatial analysis to predict faecal pollution during extreme precipitation events

    Science.gov (United States)

    Ward, Ray; Purnell, Sarah; Ebdon, James; Nnane, Daniel; Taylor, Huw

    2013-04-01

    The Water Framework Directive (WFD) regulates surface water quality standards in the European Union (EU). The Directive call for the identification and management of point and diffuse sources of pollution and requires the establishment of a 'programme of measures' for identified river basin districts, in order to achieve a "good status" by 2015. The hygienic quality of water is normally monitored using faecal indicator organisms (FIO), such as Escherichia coli, which indicate a potential risk to public health from human waterborne pathogens. Environmental factors influence the transmission of these pathogens and indicator organisms, and statistically significant relationships have been found between rainfall and outbreaks of waterborne disease. Climate change has been predicted to lead to an increase in severe weather events in many parts of Europe, including an increase in the frequency of extreme rainfall events. This in turn is likely to lead to an increase in incidents of human waterborne disease in Europe, unless measures are taken to predict and mitigate for such events. This study investigates a variety of environmental factors that influence the concentration of FIO in surface waters receiving faecal contamination from a variety of sources. Levels of FIO, including Escherichia coli, intestinal enterococci, somatic coliphage and GB124 (a human-specific microbial source tracking marker), were monitored in the Sussex Ouse catchment in Southeast England over a period of 26 months. These data were combined with geoinformatic environmental data within a GIS to map faecal contamination within the river. Previously, precipitation and soil erosion have been identified as major factors that can influence the concentration of these faecal markers, and studies have shown that slope, soil type and vegetation influence both the mechanisms and the rate by which erosion occurs in river catchments. Of the environmental variables studied, extreme precipitation was found to

  16. Precipitation chemistry and wet deposition in a remote wet savanna site in West Africa: Djougou (Benin)

    Science.gov (United States)

    Akpo, A. B.; Galy-Lacaux, C.; Laouali, D.; Delon, C.; Liousse, C.; Adon, M.; Gardrat, E.; Mariscal, A.; Darakpa, C.

    2015-08-01

    burning and biofuel combustions. The second highest contribution is the calcium ion (13.3 μeq·L-1), characteristic of dust aerosols from terrigenous sources, Calcium contributes up to 46% of the precipitation chemistry in Djougou. Finally, these results are compared to those obtained for other selected African sites representative of other main natural ecosystems: dry savanna and forest. The study of the African ecosystem transect indicates a pH gradient with more acidic pH in the forested ecosystem. Nitrogenous contribution to the chemical composition of rain in Lamto, wet savanna, (24%) is equivalent to the one estimated in Djougou (24%). The last contribution concerns organic acidity, which represents 7% of total ionic content of precipitation at Djougou. The relative particulate contribution PC and the relative gaseous contribution GC are calculated using the mean chemical composition measured in Djougou for the studied period. The comparison with other African sites gives 40% and 43% PC in wet savannas of Lamto (Côte d'Ivoire) and Djougou (Benin) respectively, 20% PC in the equatorial forest of Zoetele (Cameroon) and 80% PC in dry savanna of Banizoumbou (Niger). The results shown here indicate the existence of a North-South gradients of organic, marine, terrigenous and nitrogenous contributions along the transect in West and Central Africa.

  17. The potential for phosphorus pollution remediation by calcite precipitation in UK freshwaters

    Directory of Open Access Journals (Sweden)

    C. Neal

    2001-01-01

    Full Text Available This paper examines the potential for calcium carbonate to reduce phosphate pollution in freshwaters by co-precipitation, a process known as a "self cleansing mechanism". Calcium carbonate saturation levels and phosphate concentrations (SRP - soluble reactive phosphate across the major eastern UK river basins are examined to test for solubility controls. The study shows that calcite saturation varies for each catchment as a function of flow and biological activity rather than by direct regulation by SRP. Indeed, there is no evidence, for any of the rivers studied, that calcite solubility controls hold. However, for groundwater and groundwater-fed springs in the Chalk of the Thames basin, calcite saturation is observed with associated low SRP levels. A self-cleansing mechanism may well be operative within the Chalk due to two factors. Firstly, there is a high potential for nucleation on the calcite micro-crystals in the aquifer. Secondly, there are within aquifer reactions that remove the calcite nucleating inhibitors (SRP and dissolved organic carbon, DOC to levels lower than those occurring within the rivers do. These inhibitors enter the catchment at very high concentrations in association with agricultural pollution (fertilizer application and animal slurry and household contamination (e.g. sewage sources from septic tanks. Under low flow conditions, when the saturation index for calcite is at its highest, so too is the concentration of the nucleation inhibitor SRP. Companion work shows that calcite precipitation can occur at the water-sediment interface of the river and this may involve SRP removal. The data, as a whole, define an apparent bound for calcite solubility control where in the presence of nucleating centres, SRP must be less than 4 mM-P l-1 and DOC must be less than 150 mM-C l-1: a condition that does not seem to pertain within most UK rivers. Keywords: calcite, calcium carbonate, phosphate, soluble reactive phosphate, dissolved

  18. Ground-based Observations and Atmospheric Modelling of Energetic Electron Precipitation Effects on Antarctic Mesospheric Chemistry

    Science.gov (United States)

    Newnham, D.; Clilverd, M. A.; Horne, R. B.; Rodger, C. J.; Seppälä, A.; Verronen, P. T.; Andersson, M. E.; Marsh, D. R.; Hendrickx, K.; Megner, L. S.; Kovacs, T.; Feng, W.; Plane, J. M. C.

    2016-12-01

    The effect of energetic electron precipitation (EEP) on the seasonal and diurnal abundances of nitric oxide (NO) and ozone in the Antarctic middle atmosphere during March 2013 to July 2014 is investigated. Geomagnetic storm activity during this period, close to solar maximum, was driven primarily by impulsive coronal mass ejections. Near-continuous ground-based atmospheric measurements have been made by a passive millimetre-wave radiometer deployed at Halley station (75°37'S, 26°14'W, L = 4.6), Antarctica. This location is directly under the region of radiation-belt EEP, at the extremity of magnetospheric substorm-driven EEP, and deep within the polar vortex during Austral winter. Superposed epoch analyses of the ground based data, together with NO observations made by the Solar Occultation For Ice Experiment (SOFIE) onboard the Aeronomy of Ice in the Mesosphere (AIM) satellite, show enhanced mesospheric NO following moderate geomagnetic storms (Dst ≤ -50 nT). Measurements by co-located 30 MHz riometers indicate simultaneous increases in ionisation at 75-90 km directly above Halley when Kp index ≥ 4. Direct NO production by EEP in the upper mesosphere, versus downward transport of NO from the lower thermosphere, is evaluated using a new version of the Whole Atmosphere Community Climate Model incorporating the full Sodankylä Ion Neutral Chemistry Model (WACCM SIC). Model ionization rates are derived from the Polar orbiting Operational Environmental Satellites (POES) second generation Space Environment Monitor (SEM 2) Medium Energy Proton and Electron Detector instrument (MEPED). The model data are compared with observations to quantify the impact of EEP on stratospheric and mesospheric odd nitrogen (NOx), odd hydrogen (HOx), and ozone.

  19. Coupling dynamics and chemistry in the air pollution modelling of street canyons: A review.

    Science.gov (United States)

    Zhong, Jian; Cai, Xiao-Ming; Bloss, William James

    2016-07-01

    Air pollutants emitted from vehicles in street canyons may be reactive, undergoing mixing and chemical processing before escaping into the overlying atmosphere. The deterioration of air quality in street canyons occurs due to combined effects of proximate emission sources, dynamical processes (reduced dispersion) and chemical processes (evolution of reactive primary and formation of secondary pollutants). The coupling between dynamics and chemistry plays a major role in determining street canyon air quality, and numerical model approaches to represent this coupling are reviewed in this article. Dynamical processes can be represented by Computational Fluid Dynamics (CFD) techniques. The choice of CFD approach (mainly the Reynolds-Averaged Navier-Stokes (RANS) and Large-Eddy Simulation (LES) models) depends on the computational cost, the accuracy required and hence the application. Simplified parameterisations of the overall integrated effect of dynamics in street canyons provide capability to handle relatively complex chemistry in practical applications. Chemical processes are represented by a chemical mechanism, which describes mathematically the chemical removal and formation of primary and secondary species. Coupling between these aspects needs to accommodate transport, dispersion and chemical reactions for reactive pollutants, especially fast chemical reactions with time scales comparable to or shorter than those of typical turbulent eddies inside the street canyon. Different approaches to dynamical and chemical coupling have varying strengths, costs and levels of accuracy, which must be considered in their use for provision of reference information concerning urban canopy air pollution to stakeholders considering traffic and urban planning policies. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. NATO Advanced Study Institute on Pollutants from Combustion Formation and Impact on Atmospheric Chemistry

    CERN Document Server

    2000-01-01

    This volume is based on the lectures presented at the NATO Advanced Study Institute: (ASI) «Pollutants Formation from Combustion. Formation Mechanisms and Impact on th th Atmospheric Chemistry» held in Maratea, Italy, from 13 to 26 september 1998. Preservation of the environment is of increasing concern in individual countries but also at continental or world scales. The structure of a NATO ASI which involve lecturers and participants of different nationalities was thought as especially well suited to address environmental issues. As combustion is known to substantially contribute to the damaging of the atmosphere, it was natural to concentrate the ASI program on reviewing the currently available knowledge of the formation mechanisms of the main pollutants liberated by combustion systems. In most situations, pollutants are present as trace components and their formation and removal is strongly conditioned by the chemical reactions initiated by fuel consumption. Therefore specific lectures were aimed at defi...

  1. Nitrate pollution and surface water chemistry in Shimabara, Nagasaki Prefecture, Japan

    Science.gov (United States)

    Nakagawa, K.; Amano, H.

    2017-12-01

    Shimabara city has been experiencing serious nitrate pollution in groundwater. To evaluate nitrate pollution and water chemistry in surface water, water samples were collected at 42 sampling points in 15 rivers in Shimabara including a part of Unzen city from January to February 2017. Firstly, spatial distribution of water chemistry was assessed by describing stiff and piper-trilinear diagrams using major ions concentrations. Most of the samples showed Ca-HCO3 or Ca-(NO3+SO4) water types. It corresponds to groundwater chemistry. Some samples were classified into characteristic water types such as Na-Cl, (Na+K)-HCO3, and Ca-Cl. These results indicate sea water mixing and anthropogenic pollution. At the upstream of Nishi-river, although water chemistry showed Ca-HCO3, ions concentrations were higher than that of the other rivers. It indicates that this site was affected by the peripheral anthropogenic activities. Secondly, nitrate-pollution assessment was performed by using NO3-, NO2-, coprostanol (5β(H)-Cholestan-3β-ol), and cholestanol (5α(H)-Cholestan-3β-ol). NO2-N was detected at the 2 sampling points and exceeded drinking standard 0.9 mg L-1 for bottle-fed infants (WHO, 2011). NO3-N + NO2-N concentrations exceeded Japanese drinking standard 10 mg L-1 at 18 sampling points. The highest concentration was 27.5 mg L-1. Higher NO3-N levels were observed in the rivers in the northern parts of the study area. Coprostanol has been used as a fecal contamination indicator, since it can be found in only feces of higher animals. Coprostanol concentrations at 8 sampling points exceeded 700 ng L-1 (Australian drinking water standard). Coprostanol has a potential to distinguish the nitrate pollution sources between chemical fertilizer or livestock wastes, since water samples with similar NO3-N + NO2-N concentration showed distinct coprostanol concentration. The sterols ratio (5β/ (5β+5α)) exceeded 0.5 at 18 sampling points. This reveals that fecal pollution has occurred.

  2. Anthropogenic imprints on nitrogen and oxygen isotopic composition of precipitation nitrate in a nitrogen-polluted city in southern China

    Science.gov (United States)

    Fang, Y. T.; Koba, K.; Wang, X. M.; Wen, D. Z.; Li, J.; Takebayashi, Y.; Liu, X. Y.; Yoh, M.

    2011-02-01

    Nitric acid (HNO3) or nitrate (NO3-) is the dominant sink for reactive nitrogen oxides (NOx = NO + NO2) in the atmosphere. In many Chinese cities, HNO3 is becoming a significant contributor to acid deposition. In the present study, we measured nitrogen (N) and oxygen (O) isotopic composition of NO3- in 113 precipitation samples collected from Guangzhou City in southern China over a two-year period (2008 and 2009). We attempted to better understand the spatial and seasonal variability of atmospheric NOx sources and the NO3- formation pathways in this N-polluted city in the Pearl River Delta region. The δ15N values of NO3- (versus air N2) ranged from -4.9 to +10.1‰, and averaged +3.9‰ in 2008 and +3.3‰ in 2009. Positive δ15N values were observed throughout the year, indicating the anthropogenic contribution of NOx emissions, particularly from coal combustion. Different seasonal patterns of δ15N-NO3- were observed between 2008 and 2009, which might reflect different human activities associated with the global financial crisis and the intensive preparations for the 16th Asian Games. Nitrate δ18O values (versus Vienna Standard Mean Ocean Water) varied from +33.4 to +86.5‰ (average +65.0‰ and +67.0‰ in 2008 and 2009, respectively), a range being lower than those reported for high latitude and polar areas. Sixteen percent of δ18O values was observed lower than the expected minimum of +55‰ at our study site. This was likely caused by the reaction of NO with peroxy radicals; peroxy radicals can compete with O3 to convert NO to NO2, thereby donate O atoms with much lower δ18O value than that of O3 to atmospheric NO3-. Our results highlight that the influence of human activities on atmospheric chemistry can be recorded by the N and O isotopic composition of atmospheric NO3- in a N-polluted city.

  3. Comparison of precipitation chemistry measurements obtained by the Canadian Air and Precipitation Monitoring Network and National Atmospheric Deposition Program for the period 1995-2004

    Science.gov (United States)

    Wetherbee, Gregory A.; Shaw, Michael J.; Latysh, Natalie E.; Lehmann, Christopher M.B.; Rothert, Jane E.

    2010-01-01

    Precipitation chemistry and depth measurements obtained by the Canadian Air and Precipitation Monitoring Network (CAPMoN) and the US National Atmospheric Deposition Program/National Trends Network (NADP/NTN) were compared for the 10-year period 1995–2004. Colocated sets of CAPMoN and NADP instrumentation, consisting of precipitation collectors and rain gages, were operated simultaneously per standard protocols for each network at Sutton, Ontario and Frelighsburg, Ontario, Canada and at State College, PA, USA. CAPMoN samples were collected daily, and NADP samples were collected weekly, and samples were analyzed exclusively by each network’s laboratory for pH, H + , Ca2+  , Mg2+  , Na + , K + , NH+4 , Cl − , NO−3 , and SO2−4 . Weekly and annual precipitation-weighted mean concentrations for each network were compared. This study is a follow-up to an earlier internetwork comparison for the period 1986–1993, published by Alain Sirois, Robert Vet, and Dennis Lamb in 2000. Median weekly internetwork differences for 1995–2004 data were the same to slightly lower than for data for the previous study period (1986–1993) for all analytes except NO−3 , SO2−4 , and sample depth. A 1994 NADP sampling protocol change and a 1998 change in the types of filters used to process NADP samples reversed the previously identified negative bias in NADP data for hydrogen-ion and sodium concentrations. Statistically significant biases (α = 0.10) for sodium and hydrogen-ion concentrations observed in the 1986–1993 data were not significant for 1995–2004. Weekly CAPMoN measurements generally are higher than weekly NADP measurements due to differences in sample filtration and field instrumentation, not sample evaporation, contamination, or analytical laboratory differences.

  4. Changes of chemistry of precipitation on the area affected by imissions from hard coal power plant in the years 1977-1994

    International Nuclear Information System (INIS)

    Zablocki, Z.

    1996-01-01

    The changes of precipitation chemistry was studied on 9 sites in the distance 0.2-13.5 km from Dolna Odra power plant during the years 1977-1994. The results of long-term studies of changes of precipitation reaction and amounts of sulfur in precipitation on the area were shown as chronotoposequences. The results indicated on some positive changes in chemistry of precipitation in 1991-1994 years as compared to the period of 1986-1990 which manifested as decrease as yearly averages of amounts of sulfur and nitrate-nitrogen in precipitation and decrease of percentage of monthly measurements of precipitation with very acid reaction. (author). 11 refs, 2 figs, 1 tab

  5. Twenty-year inter-annual trends and seasonal variations in precipitation and stream water chemistry at the Bear Brook Watershed in Maine, USA

    Czech Academy of Sciences Publication Activity Database

    Navrátil, Tomáš; Norton, S. A.; Fernandez, I. J.; Nelson, S. J.

    2010-01-01

    Roč. 171, 1/4 (2010), s. 23-45 ISSN 0167-6369 Institutional research plan: CEZ:AV0Z30130516 Keywords : Bear Brook Watershed in Maine * precipitation chemistry * stream chemistry * seasonality * long-term trends Subject RIV: DD - Geochemistry Impact factor: 1.436, year: 2010

  6. Yielding Unexpected Results: Precipitation of Ba[subscript3](PO[subscript4])[subscript2] and Implications for Teaching Solubility Principles in the General Chemistry Curriculum

    Science.gov (United States)

    Hazen, Jeffery L.; Cleary, David A.

    2014-01-01

    Precipitation of barium phosphate from aqueous solutions of a barium salt and a phosphate salt forms the basis for a number of conclusions drawn in general chemistry. For example, the formation of a solid white precipitate is offered as evidence that barium phosphate is insoluble. Furthermore, analysis of the supernatant is used to illustrate the…

  7. Radon, water chemistry and pollution check by volatile organic compounds in springs around Popocatepetl volcano, Mexico

    Directory of Open Access Journals (Sweden)

    M. Mena

    2005-06-01

    Full Text Available Popocatepetl volcano is a high-risk active volcano in Central Mexico where the highest population density in the country is settled. Radon in the soil and groundwater together with water chemistry from samples of nearby springs were analysed as a function of the 2002-2003 volcanic activity. The measurements of soil radon indicated fluctuations related to both the meteorological and sporadic explosive events. Groundwater radon showed essential differences in concentration due to the specific characteristics of the studied springs. Water chemistry showed also stability along the monitoring period. No anthropogenic pollution from Volatile Organic Compounds (VOCs was observed. An overview of the soil radon behaviour as a function of the volcanic activity in the period 1994-2002 is also discussed.

  8. Impact of two chemistry mechanisms fully coupled with mesoscale model on the atmospheric pollutants distribution

    Science.gov (United States)

    Arteta, J.; Cautenet, S.; Taghavi, M.; Audiffren, N.

    Air quality models (AQM) consist of many modules (meteorology, emission, chemistry, deposition), and in some conditions such as: vicinity of clouds or aerosols plumes, complex local circulations (mountains, sea breezes), fully coupled models (online method) are necessary. In order to study the impact of lumped chemical mechanisms in AQM simulations, we examine the ability of both different chemical mechanisms: (i) simplified: Condensed Version of the MOdèle de Chimie Atmosphérique 2.2 (CV-MOCA2.2), and (ii) reference: Regional Atmospheric Chemistry Model (RACM), which are coupled online with the Regional Atmospheric Modeling Systems (RAMS) model, on the distribution of pollutants. During the ESCOMPTE experiment (Expérience sur Site pour COntraindre les Modèles de Pollution et de Transport d'Emissions) conducted over Southern France (including urban and industrial zones), Intensive observation periods (IOP) characterized by various meteorological and mixed chemical conditions are simulated. For both configurations of modeling, numerical results are compared with surface measurements (75 stations) for primary (NO x) and secondary (O 3) species. We point out the impact of the two different chemical mechanisms on the production of species involved in the oxidizing capacity such as ozone and radicals within urban and industrial areas. We highlight that both chemical mechanisms produce very similar results for the main pollutants (NO x and O 3) in three-dimensional (3D) distribution, despite large discrepancies in 0D modeling. For ozone concentration, we found sometimes small differences (5-10 ppb) between the mechanisms under study according to the cases (polluted or not). The relative difference between the two mechanisms over the whole domain is only -7% for ozone from CV-MOCA 2.2 versus RACM. When the order of magnitude is needed rather than an accurate estimate, a reduced mechanism is satisfactory. It has the advantage of running faster (four times less than CPU

  9. Meso-scale modeling of air pollution transport/chemistry/deposition and its application

    International Nuclear Information System (INIS)

    Kitada, Toshihiro

    2007-01-01

    Transport/chemistry/deposition model for atmospheric trace chemical species is now regarded as an important tool for an understanding of the effects of various human activities, such as fuel combustion and deforestation, on human health, eco-system, and climate and for planning of appropriate control of emission sources. Several 'comprehensive' models have been proposed such as RADM (Chang, et al., 1987), STEM-II (Carmichael, et al., 1986), and CMAQ (Community Multi-scale Air Quality model, e.g., EPA website, 2003); the 'comprehensive' models include not only gas/aerosol phase chemistry but also aqueous phase chemistry in cloud/rain water in addition to the processes of advection, diffusion, wet deposition (mass transfer between aqueous and gas/aerosol phases), and dry deposition. The target of the development of the 'comprehensive' model will be that the model can correctly reproduce mass balance of various chemical species in the atmosphere with keeping adequate accuracy for calculated concentration distributions of chemical species. For the purpose, one of the important problems is a reliable wet deposition modeling, and here, we introduce two types of methods of 'cloud-resolving' and 'non-cloud-resolving' modeling for the wet deposition of pollutants. (author)

  10. Mobility of radiocaesium in boreal forest ecosystems: Influence of precipitation chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Steinnes, E. [Department of Chemistry, Norwegian University of Science and Technology (Norway); Gjelsvik, R.; Skuterud, L.; Thoerring, H. [Norwegian Radiation Protection Authority (Norway)

    2014-07-01

    Mobility and plant uptake of Cs in soils is generally limited by the presence of clay minerals in the soil. However, cations supplied by precipitation may substantially influence the mobility of radiocaesium in natural surface soil and subsequent transfer to food chains. The chemical composition of precipitation shows substantial variation among different areas in Norway for two main reasons. At sites close to the coast the atmospheric supply of marine cations and anions is many-fold greater than in regions shielded from marine influence by mountains. The southernmost part of the country has been, and still is, substantially affected by soil acidification due to long-range atmospheric transport of acidifying substances from areas elsewhere in Europe. This may explain a much higher greater uptake of {sup 137}Cs from the Chernobyl accident in moose in this region than elsewhere (Steinnes et al., 2009), in spite of the fact that some areas farther north received substantially greater fallout. Similarly a much greater transfer of {sup 137}Cs to natural birch forest vegetation is evident from the more acidified soils in the south than in comparable ecosystems elsewhere in the country (Thoerring et al., 2012). Repeated recordings of activity levels in natural surface soils showed faster leaching of Chernobyl {sup 137}Cs relative to inland areas not only in the south but also in coastal areas farther north (Gjelsvik and Steinnes, 2013), indicating that the amounts of marine cations in precipitation also has an appreciable effect on the Cs leaching. The geographical leaching differences still became less prominent with time. Recent lysimeter experiments with undisturbed soil columns obtained from an area receiving high radiocaesium deposition from the Chernobyl accident, applying precipitation with ionic composition characteristic of the different regions mentioned above, did not change the current depth distribution of {sup 137}Cs. However, acidic precipitation increased

  11. A statistical intercomparison between "urban" and "rural" precipitation chemistry data from greater Manchester and two nearby secondary national network sites in the United Kingdom

    Science.gov (United States)

    Lee, David S.; Longhurst, James W. S.

    Precipitation chemistry data from a dense urban monitoring network in Greater Manchester, northwest England, were compared with interpolated values from the U.K. secondary national acid deposition monitoring network for the year 1988. Differences were found to be small. However, when data from individual sites from the Greater Manchester network were compared with data from the two nearest secondary national network sites, significant differences were found using simple and complex statistical analyses. Precipitation chemistry at rural sites could be similar to that at urban sites, but the sources of some ions were thought to be different. The synoptic-scale gradients of precipitation chemistry, as shown by the secondary national network, also accounted for some of the differences.

  12. Manual for the GAW Precipitation Chemistry Programme: Guidelines, Data Quality Objectives and Standard Operating Procedures

    Science.gov (United States)

    2004-11-01

    Prof. Dr. Hans-Walter Georgii, February 1982. 9. An Assessment of BAPMoN Data Currently Available on the Concentration of CO2 in the Atmosphere by...134). 35. Provisional Daily Atmospheric CO2 Concentrations as Measured at BAPMoN Sites for the Year 1983. December 1985 (WMO TD No. 77). 36...and Atmospheric Chemistry, Santiago , Chile , 9-15 January 1991 (WMO TD No. 633). 71. Report of the Consultation of Experts to Consider Desirable

  13. Vocabulary of acid precipitation and air pollution. Terminology bulletin 175. Vocabulaire des precipitations acides et de la pollution atmospherique. Bulletin de terminologie 175

    Energy Technology Data Exchange (ETDEWEB)

    Rivard, D

    1988-01-01

    This English-French vocabulary includes about 600 concepts on acid rain as well as general air pollution terminology. A large number of official names and their abbreviations have also been incorporated into the dictionary. The vocabulary is arranged alphabeticaly into a series of terminology files, each of which begins with a main entry in English and French. The main entry represents those terms selected as being of superior terminological quality. The main entry may be followed by sub-entries, which are synonyms, and may also be followed by a definition, an example of usage, a defining context, or a terminological observation. Sub-entries are in the same alphabetical sequence as the main entries, and refer the reader to the main entry. An index of French terms is also included. 243 refs.

  14. Changing regional emissions of airborne pollutants reflected in the chemistry of snowpacks and wetfall in the Rocky Mountain region, USA, 1993–2012

    Science.gov (United States)

    Ingersoll, George P.; Miller, Debra C.; Morris, Kristi H.; McMurray, Jill A.; Port, Garrett M.; Caruso, Brian

    2016-01-01

    Wintertime precipitation sample data from 55 Snowpack sites and 17 National Atmospheric Deposition Program (NADP)/National Trends Network Wetfall sites in the Rocky Mountain region were examined to identify long-term trends in chemical concentration, deposition, and precipitation using Regional and Seasonal Kendall tests. The Natural Resources Conservation Service snow-telemetry (SNOTEL) network provided snow-water-equivalent data from 33 sites located near Snowpack- and NADP Wetfall-sampling sites for further comparisons. Concentration and deposition of ammonium, calcium, nitrate, and sulfate were tested for trends for the period 1993–2012. Precipitation trends were compared between the three monitoring networks for the winter seasons and downward trends were observed for both Snowpack and SNOTEL networks, but not for the NADP Wetfall network. The dry-deposition fraction of total atmospheric deposition, relative to wet deposition, was shown to be considerable in the region. Potential sources of regional airborne pollutant emissions were identified from the U.S. Environmental Protection Agency 2011 National Emissions Inventory, and from long-term emissions data for the period 1996–2013. Changes in the emissions of ammonia, nitrogen oxides, and sulfur dioxide were reflected in significant trends in snowpack and wetfall chemistry. In general, ammonia emissions in the western USA showed a gradual increase over the past decade, while ammonium concentrations and deposition in snowpacks and wetfall showed upward trends. Emissions of nitrogen oxides and sulfur dioxide declined while regional trends in snowpack and wetfall concentrations and deposition of nitrate and sulfate were downward.

  15. An improved export coefficient model to estimate non-point source phosphorus pollution risks under complex precipitation and terrain conditions.

    Science.gov (United States)

    Cheng, Xian; Chen, Liding; Sun, Ranhao; Jing, Yongcai

    2018-05-15

    To control non-point source (NPS) pollution, it is important to estimate NPS pollution exports and identify sources of pollution. Precipitation and terrain have large impacts on the export and transport of NPS pollutants. We established an improved export coefficient model (IECM) to estimate the amount of agricultural and rural NPS total phosphorus (TP) exported from the Luanhe River Basin (LRB) in northern China. The TP concentrations of rivers from 35 selected catchments in the LRB were used to test the model's explanation capacity and accuracy. The simulation results showed that, in 2013, the average TP export was 57.20 t at the catchment scale. The mean TP export intensity in the LRB was 289.40 kg/km 2 , which was much higher than those of other basins in China. In the LRB topographic regions, the TP export intensity was the highest in the south Yanshan Mountains and was followed by the plain area, the north Yanshan Mountains, and the Bashang Plateau. Among the three pollution categories, the contribution ratios to TP export were, from high to low, the rural population (59.44%), livestock husbandry (22.24%), and land-use types (18.32%). Among all ten pollution sources, the contribution ratios from the rural population (59.44%), pigs (14.40%), and arable land (10.52%) ranked as the top three sources. This study provides information that decision makers and planners can use to develop sustainable measures for the prevention and control of NPS pollution in semi-arid regions.

  16. Thermoluminescence and photoluminescence properties of NaCl:Mn, NaCL:Cu nano-particles produced using co-precipitation and sono-chemistry methods

    Energy Technology Data Exchange (ETDEWEB)

    Mehrabi, M. [Faculty of Physics, University of Kashan, Kashan (Iran, Islamic Republic of); Zahedifar, M. [Faculty of Physics, University of Kashan, Kashan (Iran, Islamic Republic of); Institute of Nanosince and Nanotechnology, University of Kashan, Kashan (Iran, Islamic Republic of); Saeidi-Sogh, Z. [Institute of Nanosince and Nanotechnology, University of Kashan, Kashan (Iran, Islamic Republic of); Ramazani-Moghaddam-Arani, A., E-mail: ramazmo@kashanu.ac.ir [Institute of Nanosince and Nanotechnology, University of Kashan, Kashan (Iran, Islamic Republic of); Sadeghi, E. [Faculty of Physics, University of Kashan, Kashan (Iran, Islamic Republic of); Institute of Nanosince and Nanotechnology, University of Kashan, Kashan (Iran, Islamic Republic of); Harooni, S. [Institute of Nanosince and Nanotechnology, University of Kashan, Kashan (Iran, Islamic Republic of)

    2017-02-21

    The NaCl: Cu and NaCl: Mn nanoparticles (NPs) were produced by co-precipitation and sono-chemistry methods and their thermoluminescence (TL) and photoluminescence (PL) properties were studied. By decreasing the particles size a considerable increase in sensitivity of the samples to high dose gamma radiation was observed. The NPs produced by sono-chemistry method have smaller size, homogeneous structure, more sensitivity to high gamma radiation and less fading than of those produced by co-precipitation method.

  17. Fluoride pollution of atmospheric precipitation and its relationship with air circulation and weather patterns (Wielkopolski National Park, Poland).

    Science.gov (United States)

    Walna, Barbara; Kurzyca, Iwona; Bednorz, Ewa; Kolendowicz, Leszek

    2013-07-01

    A 2-year study (2010-2011) of fluorides in atmospheric precipitation in the open area and in throughfall in Wielkopolski National Park (west-central Poland) showed their high concentrations, reaching a maximum value of 2 mg/l under the tree crowns. These high values indicate substantial deposition of up to 52 mg/m(2)/year. In 2011, over 51% of open area precipitation was characterized by fluoride concentration higher than 0.10 mg/l, and in throughfall such concentrations were found in more than 86% of events. In 2010, a strong connection was evident between fluoride and acid-forming ions, and in 2011, a correlation between phosphate and nitrite ions was seen. Analysis of available data on F(-) concentrations in the air did not show an unequivocal effect on F(-) concentrations in precipitation. To find reasons for and source areas of high fluoride pollution, the cases of extreme fluoride concentration in rainwater were related to atmospheric circulation and weather patterns. Weather conditions on days of extreme pollution were determined by movement of weather fronts over western Poland, or by small cyclonic centers with meteorological fronts. Macroscale air advection over the sampling site originated in the western quadrant (NW, W, and SW), particularly in the middle layers of the troposphere (2,500-5,000 m a.s.l.). Such directions indicate western Poland and Germany as possible sources of the pollution. At the same time in the lower troposphere, air inflow was frequently from the north, showing short distance transport from local emitters, and from the agglomeration of Poznań.

  18. Local and regional factors affecting the chemistry of precipitation in the spanish basque country

    International Nuclear Information System (INIS)

    Ezcurra, A.; Durana, N.; Casado, H.; Lacaux, J.P.; Pham Van Dinh; Garcia, C.

    1991-01-01

    The study deals with near 300 rain events sampled by means of a network of five automatic devices operating from January 1986 to November 1988. The results show that, on a local-scale, the rain chemistry is affected by the marine source of gases and particles. On a regional-scale, values of pH ranging from 5.5 to 4.8 are noticed. The acidity of rain has an anthropogenic origin that is mainly linked to the NO 3 - content. The acidity is reinforced by air flow from continental Europe. By contrast, rain water with a basic character is related to the air fluxes from Southern Spain that increase the rain content in Ca 2+ [fr

  19. Aerosol impacts on California winter clouds and precipitation during CalWater 2011: local pollution vs. long-range transported dust

    Science.gov (United States)

    Fan, J.; Leung, L. R.; DeMott, P. J.; Comstock, J. M.; Singh, B.; Rosenfeld, D.; Tomlinson, J. M.; White, A.; Prather, K. A.; Minnis, P.; Ayers, J. K.; Min, Q.

    2013-07-01

    Mineral dust aerosols often observed over California in winter/spring, associated with long-range transport from Asia and Sahara, have been linked to enhanced precipitation based on observations. Local anthropogenic pollution, on the other hand, was shown in previous observational and modeling studies to reduce precipitation. Here we incorporate recent developments in ice nucleation parameterizations to link aerosols with ice crystal formation in a spectral-bin cloud microphysical model coupled with the Weather Research and Forecasting (WRF) model, to examine the relative and combined impacts of dust and local pollution particles on cloud properties and precipitation type and intensity. Simulations are carried out for two cloud cases with contrasting meteorology and cloud dynamics that occurred on 16 February (FEB16) and 2 March (MAR02) from the CalWater 2011 field campaign. In both cases, observations show the presence of dust or dust/biological particles in a relative pristine environment. The simulated cloud microphysical properties and precipitation show reasonable agreement with aircraft and surface measurements. Model sensitivity experiments indicate that in the pristine environment, the dust/biological aerosol layers increase the accumulated precipitation by 10-20% from the Central Valley to the Sierra Nevada Mountains for both FEB16 and MAR02 due to a 40% increase in snow formation, validating the observational hypothesis. Model results show that local pollution increases precipitation over the windward slope of the mountains by few percent due to increased snow formation when dust is present but reduces precipitation by 5-8% if dust is removed on FEB16. The effects of local pollution on cloud microphysics and precipitation strongly depend on meteorology including the strength of the Sierra Barrier Jet, and cloud dynamics. This study further underscores the importance of the interactions between local pollution, dust, and environmental conditions for

  20. Aerosol impacts on California winter clouds and precipitation during CalWater 2011: local pollution versus long-range transported dust

    Science.gov (United States)

    Fan, J.; Leung, L. R.; DeMott, P. J.; Comstock, J. M.; Singh, B.; Rosenfeld, D.; Tomlinson, J. M.; White, A.; Prather, K. A.; Minnis, P.; Ayers, J. K.; Min, Q.

    2014-01-01

    Mineral dust aerosols often observed over California in winter and spring, associated with long-range transport from Asia and the Sahara, have been linked to enhanced precipitation based on observations. Local anthropogenic pollution, on the other hand, was shown in previous observational and modeling studies to reduce precipitation. Here we incorporate recent developments in ice nucleation parameterizations to link aerosols with ice crystal formation in a spectral-bin cloud microphysical model coupled with the Weather Research and Forecasting (WRF) model in order to examine the relative and combined impacts of dust and local pollution particles on cloud properties and precipitation type and intensity. Simulations are carried out for two cloud cases (from the CalWater 2011 field campaign) with contrasting meteorology and cloud dynamics that occurred on 16 February (FEB16) and 2 March (MAR02). In both cases, observations show the presence of dust and biological particles in a relative pristine environment. The simulated cloud microphysical properties and precipitation show reasonable agreement with aircraft and surface measurements. Model sensitivity experiments indicate that in the pristine environment, the dust and biological aerosol layers increase the accumulated precipitation by 10-20% from the Central Valley to the Sierra Nevada for both FEB16 and MAR02 due to a ~40% increase in snow formation, validating the observational hypothesis. Model results show that local pollution increases precipitation over the windward slope of the mountains by a few percent due to increased snow formation when dust is present, but reduces precipitation by 5-8% if dust is removed on FEB16. The effects of local pollution on cloud microphysics and precipitation strongly depend on meteorology, including cloud dynamics and the strength of the Sierra Barrier Jet. This study further underscores the importance of the interactions between local pollution, dust, and environmental

  1. Biology and chemistry of three Pennsylvania lakes: responses to acid precipitation

    Energy Technology Data Exchange (ETDEWEB)

    Bradt, P.T.; Dudley, J.L.; Berg, M.B.; Barrasso, D.S.

    1986-09-01

    The biology and chemistry of three northeastern Pennsylvania lakes was studied from summer 1981 through summer 1983 to evaluate lakes with different sensitivities to acidification. At the acidified lake there were fewer phytoplankton and zooplankton species than at the moderately sensitive lakes. The most numerous plankton species in all three lakes are reportedly acid tolerant. Among the benthic macro-invertebrates (BMI) there were more acid tolerant Chironomidae at the acidified lake, but more acid intolerant Ephemeroptera and Mollusca and a higher wet weight at the least sensitive lake. There were no differences among the lakes' BMI mean total numbers or mean number of taxa. The fish community at the acidified lake was dominated by stunted Lepomis gibbosus, but L. machrochirous were most abundant in the other lakes. Principal component analysis suggested a shift in all three lakes over the sampling period toward combined lower pH, alkalinity, specific conductance, Ca and Mg and higher Al and Mn. Such chemical changes have been associated with acidification. The rate and extent of acidification appeared to be controlled by geological and hydrological characteristics of the drainage basins. 38 refs.

  2. Biology and chemistry of tree Pennsylvania lakes: responses to acid precipitation. [Lepomis gibbosus; Lepomis machrochirous

    Energy Technology Data Exchange (ETDEWEB)

    Bradt, P.T.; Dudley, J.L.; Berg, M.B.; Barrasso, D.S.

    1986-01-01

    The biology and chemistry of three northeastern Pennsylvania lakes was studied from summer 1981 through summer 1983 to evaluate lakes with different sensitivities to acidification. At the acidifies lake (total alkalinity par. delta 0.0 ..mu..eq L/sup -1/) there were fewer phytoplankton and zooplankton species than at the moderately sensitive lakes. The most numerous plankton species in all three lakes are reportedly acid tolerant. Among the benthic macro- invertebrates (BMI) there were more acid tolerant Chironomidae at the acidified lake, but more acid intolerant Ephemeroptera and Mollusca and a higher wet weight at the least sensitive lake. There were no differences among the lakes' BMI mean total numbers or mean number of taxa. The fish community at the acidified lake was dominated by stunted Lepomis gibbosus, but L. machrochirous were most abundant in the other lakes. Principal component analysis suggested a shift in all three lakes over the sampling period toward combined lower pH, alkalinity, specific conductance, Ca, and Mg and higher Al and Mn. Such chemical changes have been associated with acidification. The rate and extent of acidification appeared to be controlled by geological and hydrological characteristics of the drainage basins.

  3. Migration chemistry

    International Nuclear Information System (INIS)

    Carlsen, L.

    1992-05-01

    Migration chemistry, the influence of chemical -, biochemical - and physico-chemical reactions on the migration behaviour of pollutants in the environment, is an interplay between the actual natur of the pollutant and the characteristics of the environment, such as pH, redox conditions and organic matter content. The wide selection of possible pollutants in combination with varying geological media, as well as the operation of different chemical -, biochemical - and physico-chemical reactions compleactes the prediction of the influence of these processes on the mobility of pollutants. The report summarizes a wide range of potential pollutants in the terrestrial environment as well as a variety of chemical -, biochemical - and physico-chemical reactions, which can be expected to influence the migration behaviour, comprising diffusion, dispersion, convection, sorption/desorption, precipitation/dissolution, transformations/degradations, biochemical reactions and complex formation. The latter comprises the complexation of metal ions as well as non-polar organics to naturally occurring organic macromolecules. The influence of the single types of processes on the migration process is elucidated based on theoretical studies. The influence of chemical -, biochemical - and physico-chemical reactions on the migration behaviour is unambiguous, as the processes apparently control the transport of pollutants in the terrestrial environment. As the simple, conventional K D concept breaks down, it is suggested that the migration process should be described in terms of the alternative concepts chemical dispersion, average-elution-time and effective retention. (AB) (134 refs.)

  4. Long-term flow/chemistry feedback in a porous medium with heterogenous permeability: Kinetic control of dissolution and precipitation

    International Nuclear Information System (INIS)

    Bolton, E.W.; Lasaga, A.C.; Rye, D.M.

    1999-01-01

    The kinetics of dissolution and precipitation is of central importance to understanding the long-term evolution of fluid flows in crustal environments, with implications for problems as diverse as nuclear waste disposal and crustal evolution. The authors examine the dynamics of such evolution for several geologically relevant permeability distributions (models for en-echelon cracks, an isolated sloping fractured zone, and two sloping high-permeability zones that are close enough together to interact). Although the focus is on a simple quartz matrix system, generic features emerge from this study that can aid in the broader goal of understanding the long-term feedback between flow and chemistry, where dissolution and precipitation is under kinetic control. Examples of thermal convection in a porous medium with spatially variable permeability reveal features of central importance to water-rock interaction. After a transient phase, an accelerated rate of change of porosity may be used with care to decrease computational time, as an alternative to the quasi-stationary state approximation (Lichtner, 1988). Kinetic effects produce features not expected by traditional assumptions made on the basis of equilibrium, for example, that cooling fluids are oversaturated and heating fluids are undersaturated with respect to silicic acid equilibrium. Indeed, the authors observe regions of downwelling oversaturated fluid experiencing heating and regions of upwelling, yet cooling, undersaturated fluid. When oscillatory convection is present, the amplitudes of oscillation generally increase with time in near-surface environments, whereas amplitudes tend to decrease over long times near the heated lower boundary. The authors examine the scaling behavior of characteristic length scales, of terms in the solute equation, and of the typical deviation from equilibrium, each as a function of the kinetic rate parameters

  5. The complex synthesis and solid state chemistry of ceria-lanthana solid solutions prepared via a hexamethylenetetramine precipitation

    International Nuclear Information System (INIS)

    Fleming, P.G.; Holmes, J.D.; Otway, D.J.; Morris, M.A.

    2011-01-01

    Mixed oxide solid solutions are becoming ever more commercially important across a range of applications. However, their synthesis can be problematical. Here, we show that ceria-lanthana solid solutions can be readily prepared via simple precipitation using hexamethylenetetramine. However, the solution chemistry can be complex, which results in the precipitated particles having a complex structure and morphology. Great care must be taken in both the synthesis and characterisation to quantify the complexity of the product. Even very high heat treatments were not able to produce highly homogeneous materials and X-ray diffractions reveals the non-equilibrium form of particles prepared in this way. Unexpected crystal structures are revealed including a new metastable cubic La 2 O 3 phase. - Graphical abstract: The suggested mechanism for the formation of dual fluorite phase particles, where Step 1 corresponds to room temperature aging, Step 2; heating the solution to 90 deg. C, Step 3; cooling of the solution to room temperature, Step 4; calcination to 500 deg. C, Step 5; calcination to 700 deg. C and Step 6; calcination to 1300 deg. C. The terminology of e.g. La 1-x Ce x (OH) 3 is used to indicate the formation of a mixed oxy-hydroxy participate rather than a definitive assignment of stoichiometry. Similarly, La 1-y Ce y O 2 only implies a mixed solid solution. Highlights: → Mol% of prepared Ce-La oxides did not follow that of reactant mol%. → Complex reaction pathway found to be dependent on metal solution concentrations. → At certain concentrations core shell particles were found to form. → A reaction model was produced based on cationic solubility. → Report lanthana solubility higher than previously reported in CeO 2 .

  6. Evaluation of pollutant emissions in North China Plain using aircraft measurements from the Air Chemistry Research In Asia (ARIAs) campaign

    Science.gov (United States)

    He, H.; Ren, X.; Li, Z.; Dickerson, R. R.

    2017-12-01

    The North China Plain (NCP) is one of the most populated and polluted regions on Earth. With rapid economic development in past decades, air pollution including heavy atmospheric aerosol loadings became severe in this region, leading to environmental and climate problems. An aircraft campaign, Air Chemistry Research In Asia (ARIAs), was conducted in spring 2016 (in parallel to KORUS-AQ) to understand air quality in the NCP and transport of air pollutants from this area. Measurements of trace gases such as O3, CO, and SO2 and aerosol optical properties were analyzed to investigate the anthropogenic emissions in the NCP. Both high-efficiency combustion such as from automobiles and modern power plants as well as low-efficiency combustion such as from biomass burnings were identified. Transformations of primary pollutants and formation of secondary pollutants were simulated using the EPA CMAQ v5.2 model. The global HTAP-EDGAR v4.2 emission inventory of year 2010 was processed with SMOKE v4.5 to drive CMAQ. Modeling results were evaluated with aircraft observations to improve our knowledge of anthropogenic emissions and transport. We also used satellite observations including OMI SO2/NO2 and MODIS AOD to evaluate the model performance in the NCP. Through the comparison, we estimated the changes in emissions of major anthropogenic pollutants from 2010 to 2016. Sensitivity experiments with improved emission inventory were conducted to better investigate the air pollution in the NCP.

  7. Using a chemistry transport model to account for the spatial variability of exposure concentrations in epidemiologic air pollution studies.

    Science.gov (United States)

    Valari, Myrto; Menut, Laurent; Chatignoux, Edouard

    2011-02-01

    Environmental epidemiology and more specifically time-series analysis have traditionally used area-averaged pollutant concentrations measured at central monitors as exposure surrogates to associate health outcomes with air pollution. However, spatial aggregation has been shown to contribute to the overall bias in the estimation of the exposure-response functions. This paper presents the benefit of adding features of the spatial variability of exposure by using concentration fields modeled with a chemistry transport model instead of monitor data and accounting for human activity patterns. On the basis of county-level census data for the city of Paris, France, and a Monte Carlo simulation, a simple activity model was developed accounting for the temporal variability between working and evening hours as well as during transit. By combining activity data with modeled concentrations, the downtown, suburban, and rural spatial patterns in exposure to nitrogen dioxide, ozone, and PM2.5 (particulate matter [PM] pollution on total nonaccidental mortality for the 4-yr period from 2001 to 2004. It was shown that the time series of the exposure surrogates developed here are less correlated across co-pollutants than in the case of the area-averaged monitor data. This led to less biased exposure-response functions when all three co-pollutants were inserted simultaneously in the same regression model. This finding yields insight into pollutant-specific health effects that are otherwise masked by the high correlation among co-pollutants.

  8. Removal of triazine-based pollutants from water by carbon nanotubes: Impact of dissolved organic matter (DOM) and solution chemistry.

    Science.gov (United States)

    Engel, Maya; Chefetz, Benny

    2016-12-01

    Adsorption of organic pollutants by carbon nanotubes (CNTs) in the environment or removal of pollutants during water purification require deep understanding of the impacts of the presence of dissolved organic matter (DOM). DOM is an integral part of environmental systems and plays a key role affecting the behavior of organic pollutants. In this study, the effects of solution chemistry (pH and ionic strength) and the presence of DOM on the removal of atrazine and lamotrigine by single-walled CNTs (SWCNTs) was investigated. The solubility of atrazine slightly decreased (∼5%) in the presence of DOM, whereas that of lamotrigine was significantly enhanced (by up to ∼70%). Simultaneous introduction of DOM and pollutant resulted in suppression of removal of both atrazine and lamotrigine, which was attributed to DOM-pollutant competition or blockage of adsorption sites by DOM. However the decrease in removal of lamotrigine was also a result of its complexation with DOM. Pre-introduction of DOM significantly reduced pollutant adsorption by the SWCNTs, whereas introduction of DOM after the pollutant resulted in the release of adsorbed atrazine and lamotrigine from the SWCNTs. These data imply that DOM exhibits higher affinity for the adsorption sites than the triazine-based pollutants. In the absence of DOM atrazine was a more effective competitor than lamotrigine for adsorption sites in SWCNTs. However, competition between pollutants in the presence of DOM revealed lamotrigine as the better competitor. Our findings help unravel the complex DOM-organic pollutant-CNT system and will aid in CNT-implementation in water-purification technologies. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Aerosol impacts on California winter clouds and precipitation during CalWater 2011: local pollution vs. long-range transported dust

    OpenAIRE

    J. Fan; L. R. Leung; P. J. DeMott; J. M. Comstock; B. Singh; D. Rosenfeld; J. M. Tomlinson; A. White; K. A. Prather; P. Minnis; J. K. Ayers; Q. Min

    2013-01-01

    Mineral dust aerosols often observed over California in winter/spring, associated with long-range transport from Asia and Sahara, have been linked to enhanced precipitation based on observations. Local anthropogenic pollution, on the other hand, was shown in previous observational and modeling studies to reduce precipitation. Here we incorporate recent developments in ice nucleation parameterizations to link aerosols with ice crystal formation in a spectral-bin cloud microphysical mode...

  10. Aerosol impacts on California winter clouds and precipitation during CalWater 2011: local pollution versus long-range transported dust

    OpenAIRE

    Fan, J.; Leung, L. R.; DeMott, P. J.; Comstock, J. M.; Singh, B.; Rosenfeld, D.; Tomlinson, J. M.; White, A.; Prather, K. A.; Minnis, P.; Ayers, J. K.; Min, Q.

    2014-01-01

    Mineral dust aerosols often observed over California in winter and spring, associated with long-range transport from Asia and the Sahara, have been linked to enhanced precipitation based on observations. Local anthropogenic pollution, on the other hand, was shown in previous observational and modeling studies to reduce precipitation. Here we incorporate recent developments in ice nucleation parameterizations to link aerosols with ice crystal formation in a spectral-bin cloud microphysical mod...

  11. E-Alerts: Environmental pollution and control (air pollution and control). E-mail newsletter

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-04-01

    Topics of discussion include the following: Air pollution from flue gases, exhaust gases, odors, dust, smog, microorganisms, etc.; Control techniques and equipment; Sampling and analytical techniques, and equipment; Waste gas recovery; Biological and ecological effects; Air pollution chemistry; Acid precipitation; Atmospheric motion; Laws, legislation, and regulations; Public administration; Economics; Land use.

  12. Response of surface water chemistry to reduced levels of acid precipitation: Comparison of trends in two regions of New York, USA

    Science.gov (United States)

    Burns, Douglas A.; McHale, M.R.; Driscoll, C.T.; Roy, K.M.

    2006-01-01

    In light of recent reductions in sulphur (S) and nitrogen (N) emissions mandated by Title IV of the Clean Air Act Amendments of 1990, temporal trends and trend coherence in precipitation (1984-2001 and 1992-2001) and surface water chemistry (1992-2001) were determined in two of the most acid-sensitive regions of North America, i.e. the Catskill and Adirondack Mountains of New York. Precipitation chemistry data from six sites located near these regions showed decreasing sulphate (SO42-), nitrate (NO3-), and base cation (CB) concentrations and increasing pH during 1984-2001, but few significant trends during 1992-2001. Data from five Catskill streams and 12 Adirondack lakes showed decreasing trends in SO42- concentrations at all sites, and decreasing trends in NO3-, CB, and H+ concentrations and increasing trends in dissolved organic carbon at most sites. In contrast, acid-neutralizing capacity (ANC increased significantly at only about half the Adirondack lakes and in one of the Catskill streams. Flow correction prior to trend analysis did not change any trend directions and had little effect on SO42- trends, but it caused several significant non-flow-corrected trends in NO3- and ANC to become non-significant, suggesting that trend results for flow-sensitive constituents are affected by flow-related climate variation. SO42- concentrations showed high temporal coherence in precipitation, surface waters, and in precipitation-surface water comparisons, reflecting a strong link between S emissions, precipitation SO42- concentrations, and the processes that affect S cycling within these regions. NO3- and H+ concentrations and ANC generally showed weak coherence, especially in surface waters and in precipitation-surface water comparisons, indicating that variation in local-scale processes driven by factors such as climate are affecting trends in acid-base chemistry in these two regions. Copyright ?? 2005 John Wiley & Sons, Ltd.

  13. The use of Pb, Sr, and Hg isotopes in Great Lakes precipitation as a tool for pollution source attribution

    Energy Technology Data Exchange (ETDEWEB)

    Sherman, Laura S., E-mail: lsaylors@umich.edu [University of Michigan, Department of Earth and Environmental Sciences, 1100 N. University Ave., Ann Arbor, MI 48109 (United States); Blum, Joel D. [University of Michigan, Department of Earth and Environmental Sciences, 1100 N. University Ave., Ann Arbor, MI 48109 (United States); Dvonch, J. Timothy [University of Michigan, Air Quality Laboratory, 1415 Washington Heights, Ann Arbor, MI 48109 (United States); Gratz, Lynne E. [University of Washington-Bothell, 18115 Campus Way NE, Bothell, WA 98011 (United States); Landis, Matthew S. [U.S. EPA, Office of Research and Development, Research Triangle Park, NC 27709 (United States)

    2015-01-01

    The anthropogenic emission and subsequent deposition of heavy metals including mercury (Hg) and lead (Pb) present human health and environmental concerns. Although it is known that local and regional sources of these metals contribute to deposition in the Great Lakes region, it is difficult to trace emissions from point sources to impacted sites. Recent studies suggest that metal isotope ratios may be useful for distinguishing between and tracing source emissions. We measured Pb, strontium (Sr), and Hg isotope ratios in daily precipitation samples that were collected at seven sites across the Great Lakes region between 2003 and 2007. Lead isotope ratios ({sup 207}Pb/{sup 206}Pb = 0.8062 to 0.8554) suggest that Pb deposition was influenced by coal combustion and processing of Mississippi Valley-Type Pb ore deposits. Regional differences in Sr isotope ratios ({sup 87}Sr/{sup 86}Sr = 0.70859 to 0.71155) are likely related to coal fly ash and soil dust. Mercury isotope ratios (δ{sup 202}Hg = − 1.13 to 0.13‰) also varied among the sites, likely due to regional differences in coal isotopic composition, and fractionation occurring within industrial facilities and in the atmosphere. These data represent the first combined characterization of Pb, Sr, and Hg isotope ratios in precipitation collected across the Great Lakes region. We demonstrate the utility of multiple metal isotope ratios in parallel with traditional trace element multivariate statistical modeling to enable more complete pollution source attribution. - Highlights: • We measured Pb, Sr, and Hg isotopes in precipitation from the Great Lakes region. • Pb isotopes suggest that deposition was impacted by coal combustion and metal production. • Sr isotope ratios vary regionally, likely due to soil dust and coal fly ash. • Hg isotopes vary due to fractionation occurring within facilities and the atmosphere. • Isotope results support conclusions of previous trace element receptor modeling.

  14. Aquatic Chemistry

    International Nuclear Information System (INIS)

    Kim, Dong Yeun; Kim, Oh Sik; Kim, Chang Guk; Park, Cheong Gil; Lee, Gwi Hyeon; Lee, Cheol Hui

    1987-07-01

    This book deals aquatic chemistry, which treats water and environment, chemical kinetics, chemical balance like dynamical characteristic, and thermodynamics, acid-base chemistry such as summary, definition, kinetics, and PH design for mixture of acid-base chemistry, complex chemistry with definition, and kinetics, precipitation and dissolution on summary, kinetics of precipitation and dissolution, and balance design oxidation and resolution with summary, balance of oxidation and resolution.

  15. Plants, Pollution and Public Engagement with Atmospheric Chemistry: Sharing the TEMPO Story Through Ozone Garden Activities

    Science.gov (United States)

    Reilly, L. G.; Pippin, M. R.; Malick, E.; Summers, D.; Dussault, M. E.; Wright, E. A.; Skelly, J.

    2016-12-01

    What do a snap-bean plant and a future NASA satellite instrument named TEMPO have in common? They are both indicators of the quality of the air we breathe. Scientists, educators, and museum and student collaborators of the Tropospheric Emissions: Monitoring Pollution (TEMPO) instrument team are developing a program model to engage learners of all ages via public ozone garden exhibits and associated activities. TEMPO, an ultraviolet and visible spectroscopy instrument due for launch on a geostationary host satellite between 2019 and 2021, will scan North America hourly to measure the major elements in the tropospheric ozone chemistry cycle, providing near real-time data with high temporal and spatial resolution. The TEMPO mission provides a unique opportunity to share the story of the effects of air quality on living organisms. A public ozone garden exhibit affords an accessible way to understand atmospheric science through a connection with nature, while providing a visual representation of the impact of ozone pollution on living organisms. A prototype ozone garden exhibit was established at the Virginia Living Museum in partnership with NASA Langley, and has served as a site to formatively evaluate garden planting and exhibit display protocols, hands-on interpretive activities, and citizen science data collection protocols for learners as young as 3 to 10 as well as older adults. The fun and engaging activities, optimized for adult-child interaction in informal or free-choice learning environments, are aimed at developing foundational science skills such as observing, comparing, classifying, and collecting and making sense of data in the context of thinking about air quality - all NGSS-emphasized scientific practices, as well as key capabilities for future contributing members of the citizen science community. As the launch of TEMPO approaches, a major public engagement effort will include disseminating this ozone garden exhibit and program model to a network of

  16. The Weekend Effect for Precipitation Over Eastern U.S.: Evidence for Midweek Storm Intensification by Pollution

    Science.gov (United States)

    Bell, Thomas

    2007-01-01

    Every week the U.S. population carries out a climate-change experiment by varying their activities with the day of the week. It is well documented that pollution levels vary on a weekly basis. Particulate aerosol pollution is generally a maximum in the middle of the week and a minimum on weekends. It is also well known that aerosols can affect precipitation, although whether they suppress or enhance storm development depends on many factors. The Tropical Rainfall Measuring Mission (TRMM) satellite has provided evidence that rain statistics change with the day of the week over the southeast U.S. and neighboring waters during the summer months (JJA) of 1998-2005. There is a midweek increase in both rain area and intensity over land, and a midweek decrease over the nearby Atlantic and perhaps the Gulf of Mexico. Statistical tests suggest that the weekly variations are very unlikely to be due to the random behavior of weather. We will discuss the TRMM evidence. Wind data from model reanalysis, rain-gauge data, and TRMM radar data all appear to be consistent with the picture that aerosols are causing summertime storms to grow more vigorously and to produce more rainfall.

  17. Effects of emission reductions at the Hayden powerplant on precipitation, snowpack, and surface-water chemistry in the Mount Zirkel Wilderness Area, Colorado, 1995-2003

    Science.gov (United States)

    Mast, M. Alisa; Campbell, Donald H.; Ingersoll, George P.

    2005-01-01

    Precipitation, snowpack, and surface-water samples collected during 1995-2003 were analyzed to evaluate the effects of emission reductions at the Hayden powerplant on water chemistry in the Mount Zirkel Wilderness Area. The Hayden powerplant, one of two large coal-fired powerplants in the Yampa Valley, was retrofitted with control systems during late 1998 and 1999 to reduce emissions of sulfur dioxide and nitrogen oxide--the primary precursors of haze and acidic precipitation. The U.S. Geological Survey, in cooperation with the Colorado Department of Public Health and Environment, evaluated three water-chemistry data sets: wet-only precipitation chemistry from the National Atmospheric Deposition Program, snowpack chemistry from the Rocky Mountain snowpack network, and surface-water chemistry from a U.S. Geological Survey long-term lakes monitoring program. Concentrations and deposition rates of selected constituents were compared for the periods before and after emission reductions at the Hayden powerplant. Data collected during 1995-98 were used to represent the pre-control period, and data collected during 2000-2003 were used to represent the post-control period. Ten stations in the National Atmospheric Deposition Program were evaluated including two that were directly downwind from the Hayden powerplant (Dry Lake and Buffalo Pass) and eight that were upwind or more distant (more than 100 kilometers) from the powerplant. Precipitation amount at all 10 precipitation stations was lower in the post-control period than the pre-control period as a result of a regional drought that persisted during the post-control period. In contrast to precipitation amount, there was no consistent pattern of change in sulfate concentrations between periods, indicating that the drought did not have a concentrating effect on sulfate or that trends in regional sulfur dioxide emissions masked its influence. Sulfate concentrations increased at three stations between periods, remained the

  18. Nanoparticles with photoinduced precipitation for the extraction of pollutants from water and soil.

    Science.gov (United States)

    Brandl, Ferdinand; Bertrand, Nicolas; Lima, Eliana Martins; Langer, Robert

    2015-07-21

    Nanotechnology may offer fast and effective solutions for environmental clean-up. Herein, amphiphilic diblock copolymers are used to develop a platform of photosensitive core-shell nanoparticles. Irradiation with ultraviolet light removes the protective layer responsible for colloidal stability; as a result, the nanoparticles are rapidly and irreversibly converted to macroscopic aggregates. The associated phase separation allows measuring the partitioning of small molecules between the aqueous phase and nanoparticles; data suggests that interactions are enhanced by decreasing the particle size. Adsorption onto nanoparticles can be exploited to efficiently remove hydrophobic pollutants from water and contaminated soil. Preliminary in vivo experiments suggest that treatment with photocleavable nanoparticles can significantly reduce the teratogenicity of bisphenol A, triclosan and 17α-ethinyl estradiol without generating obviously toxic byproducts. Small-scale pilot experiments on wastewater, thermal printing paper and contaminated soil demonstrate the applicability of the approach.

  19. Air pollution, land price development and assessment of immission control needs in urban development plans. The impact of immission pollution by sulphur dioxide and dust precipitation on property prices in residential areas of Dortmund and Duisburg

    International Nuclear Information System (INIS)

    Lee Chenjai.

    1993-01-01

    Air pollution, land price development and assessment of immission control needs in urban development plans. The impact of immission pollution by sulphur dioxide and dust precipitation on property prices in residential areas of Dortmund and Duisburg. The focus of this thesis is on studying the links between property prices and air pollution. The ground rent theory which goes back to the 16th century provides the theoretical basis for this work. RICARDO put forward the theory, that air may, under certain circumstances, - as for instance different local air pollution levels or sensitivity of locals to air quality -, which did not apply 200 years ago actually produce rent. These circumstances do indeed apply widely today - different air pollution levels in urban areas are just a case in point. Various empiricial studies in the U.S. proved that air pollution with different substances does actually influence the value of property. The ground rent influenced by air pollution is called ''air rent''. This study contains empirical studies on the influence of air pollution by sulphur dioxide SO 2 and dust precipitation on general property prices in residential areas of Dortmund between 1979 and 1989 and Duisburg between 1981 and 1989. (orig./UA) [de

  20. Chemistry

    International Nuclear Information System (INIS)

    Ferris, L.M.

    1975-01-01

    The chemical research and development efforts related to the design and ultimate operation of molten-salt breeder reactor systems are concentrated on fuel- and coolant-salt chemistry, including the development of analytical methods for use in these systems. The chemistry of tellurium in fuel salt is being studied to help elucidate the role of this element in the intergranular cracking of Hastelloy N. Studies were continued of the effect of oxygen-containing species on the equilibrium between dissolved UF 3 and dissolved UF 4 , and, in some cases, between the dissolved uranium fluorides and graphite, and the UC 2 . Several aspects of coolant-salt chemistry are under investigation. Hydroxy and oxy compounds that could be formed in molten NaBF 4 are being synthesized and characterized. Studies of the chemistry of chromium (III) compounds in fluoroborate melts were continued as part of a systematic investigation of the corrosion of structural alloys by coolant salt. An in-line voltammetric method for determining U 4+ /U 3+ ratios in fuel salt was tested in a forced-convection loop over a six-month period. (LK)

  1. Acid precipitation studies in Colorado and Wyoming: interim report of surveys of montane amphibians and water chemistry

    Science.gov (United States)

    Corn, Paul Stephen; Stolzenburg, William; Bury, R. Bruce

    1989-01-01

    Acid deposition may be detrimental or stressful to native populations of wildlife. Because many species of amphibians breed in shallow ponds created by spring rains or melting snow, they may be particularly vulnerable to the effects of acidification. From 1986 to 1988, we surveyed 105 locations in the central Rocky Mountains where amphibians had been recorded previously, and we found that two species of amphibians had experiences major losses. We found the northern leopard frog (Rana pipiens) at only 4 of 33 (12%) historically known localities, and the boreal toad (Bufo boreas) was present at 10 of 59 (17%) known localities. Three other species have not suffered region-wide declines. Tiger salamanders (Ambystoma tigrinum) and wood frogs (Rana sylvatica) were present at 45% and 69% of known localities respectively, and were observed at several localities were they had not been recorded previously. Chorus frogs (Pseudacris triseriata) suffered a catastrophic decline in population size in one population monitored since 1961, but regionally, this species was observed in 36 of 56 (64%) known localities and in another 19 localities where there were no previous records. Complete water chemistry was recorded for 41 localities, and pH was measured at 110 sites in total. Acid neutralizing capacity, pH, specific conductivity, and cation concentrations were negatively correlated with elevation. However, in mountain ponds and lakes, pH was rarely less than 6.0 during the amphibian breeding season. We tested the tolerance of embryos of the four species of frogs to low pH. The LC50 pH was 4.8 for chorus frogs, 4.4-4.7 for leopard frogs, 4.4-4.5 for boreal toads, and 4.2-4.3 for wood frogs. Survival of wood frog embryos declined when exposed to aluminum concentrations of 100 µg/L or greater, but boreal toad embryos survived exposure to aluminum concentrations of 400 µg/L. Acid deposition does not appear to be a major factor in the decline of leopard frogs and boreal toads

  2. Changes of chemistry of precipitation on the area affected by imissions from hard coal power plant in the years 1977-1994; Zmiany chemizmu opadow na obszarze oddzialywania imisji z elektrowni opalanej weglem w latach 1977-1994

    Energy Technology Data Exchange (ETDEWEB)

    Zablocki, Z. [Akademia Rolnicza, Szczecin (Poland)

    1996-12-31

    The changes of precipitation chemistry was studied on 9 sites in the distance 0.2-13.5 km from Dolna Odra power plant during the years 1977-1994. The results of long-term studies of changes of precipitation reaction and amounts of sulfur in precipitation on the area were shown as chronotoposequences. The results indicated on some positive changes in chemistry of precipitation in 1991-1994 years as compared to the period of 1986-1990 which manifested as decrease as yearly averages of amounts of sulfur and nitrate-nitrogen in precipitation and decrease of percentage of monthly measurements of precipitation with very acid reaction. (author). 11 refs, 2 figs, 1 tab.

  3. Chemistry

    International Nuclear Information System (INIS)

    Ferris, L.M.

    1976-01-01

    Research progress is reported in programs on fuel-salt chemistry, properties of compounds in the Li--Te system, Te spectroscopy UF 4 --H equilibria, porous electrode studies of molten salts, fuel salt-coolant salt reactions, thermodynamic properties of transition-metal fluorides, and properties of sodium fluoroborate. Developmental work on analytical methods is summarized including in-line analysis of molten MSBR fuel, analysis of coolant-salts for tritium, analysis of molten LiF--BeF 2 --ThF 4 for Fe and analysis of LiF--BeF--ThF 4 for Te

  4. Additional information about the chemistry of precipitates by variation of the scattering contrast in SANS and SAXS experiments

    International Nuclear Information System (INIS)

    Grosse, M.

    1999-01-01

    Contrast variation experiments provide the possibility to get information about the chemical composition of heterogeneities seen in the small angle scattering experiment. Phases in complex materials can become visible or invisible by changing the contrast. A very important question in this field is the determination of the type of precipitates which are formed during neutron irradiation. These irradiation-induced precipitates are the cause for the neutron embrittlement, which is the life time limiting process for a nuclear power plant. An example is presented, which shows that with contrast variation experiments information about chemical composition of precipitates can be obtained. Several phases in complex materials can be separated. (K.A.)

  5. Pollution

    NARCIS (Netherlands)

    Dürr, E.; Jaffe, R.; Nonini, D.M.

    2014-01-01

    This essay points to the role of pollution in understanding the social construction of hierarchies and urban space. Conceptualizations of pollution and approaches to waste management always reflect the Zeitgeist and tend to be politically charged. We argue that an ethnographic approach to pollution

  6. Using high-frequency sampling to detect effects of atmospheric pollutants on stream chemistry

    Science.gov (United States)

    Stephen D. Sebestyen; James B. Shanley; Elizabeth W. Boyer

    2009-01-01

    We combined information from long-term (weekly over many years) and short-term (high-frequency during rainfall and snowmelt events) stream water sampling efforts to understand how atmospheric deposition affects stream chemistry. Water samples were collected at the Sleepers River Research Watershed, VT, a temperate upland forest site that receives elevated atmospheric...

  7. Chemistry

    International Nuclear Information System (INIS)

    Ferris, L.M.

    1975-01-01

    Research and development activities dealing with the chemical problems related to design and ultimate operation of molten-salt reactor systems are described. An experimental test stand was constructed to expose metallurgical test specimens to Te 2 vapor at defined temperatures and deposition rates. To better define the chemistry of fluoroborate coolant, several aspects are being investigated. The behavior of hydroxy and oxy compounds in molten NaBF 4 is being investigated to define reactions and compounds that may be involved in corrosion and/or could be involved in methods for trapping tritium. Two corrosion products of Hastelloy N, Na 3 CrF 6 and Na 5 Cr 3 F 14 , were identified from fluoroborate systems. The evaluation of fluoroborate and alternate coolants continued. Research on the behavior of hydrogen and its isotopes is summarized. The solubilities of hydrogen, deuterium, and helium in Li 2 BeF 4 are very low. The sorption of tritium on graphite was found to be significant (a few milligrams of tritium per kilogram of graphite), possibly providing a means of sequestering a portion of the tritium produced. Development of analytical methods continued with emphasis on voltammetric and spectrophotometric techniques for the in-line analysis of corrosion products such as Fe 2+ and Cr 3+ and the determination of the U 3+ /U 4+ ratio in MSBR fuel salt. Similar studies were conducted with the NaBF 4 --NaF coolant salt. Information developed during the previous operation of the CSTF has been assessed and used to formulate plans for evaluation of in-line analytical methods in future CSTF operations. Electroanalytical and spectrophotometric research suggests that an electroactive protonic species is present in molten NaBF 4 --NaF, and that this species rapidly equilibrates with a volatile proton-containing species. Data obtained from the CSTF indicated that tritium was concentrated in the volatile species. (JGB)

  8. CHIRAL CHEMISTRY OF PESTICIDES IN THE ENVIRONMENT WITH IMPLICATIONS FOR POLLUTION PREVENTION

    Science.gov (United States)

    Upwards of 25% of pesticides and other toxic pollutants are chiral; that is, they exist as two mirror image species called enantiomers. The enantiomers of a chiral compound have identical physical and abiotic chemical properties, but differ in biological properties such as microb...

  9. A Hands-On Approach to Teaching Environmental Awareness and Pollutant Remediation to Undergraduate Chemistry Students

    Science.gov (United States)

    Salman Ashraf, S.; Rauf, M. A.; Abdullah, Fatema H.

    2012-01-01

    Background: One of the unfortunate side effects of the industrial revolution has been the constant assault of the environment with various forms of pollution. Lately, this issue has taken a more critical dimension as prospects of global climate change and irreversible ecosystem damage are becoming a reality. Purpose: College graduates (especially…

  10. Radon, water chemistry and pollution check by volatile organic compounds in springs around Popocatepetl volcano, Mexico

    OpenAIRE

    M. Mena; G. Cisniega; B. Lopez; M. A. Armienta; C. Valdés; P. Peña; N. Segovia

    2005-01-01

    Popocatepetl volcano is a high-risk active volcano in Central Mexico where the highest population density in the country is settled. Radon in the soil and groundwater together with water chemistry from samples of nearby springs were analysed as a function of the 2002-2003 volcanic activity. The measurements of soil radon indicated fluctuations related to both the meteorological and sporadic explosive events. Groundwater radon showed essential differences in concentration d...

  11. Aerosol pollution in urban and industrialized area under marine influence: physical-chemistry of particles

    International Nuclear Information System (INIS)

    Rimetz, J.

    2007-12-01

    Harbors for trade are known as highly urbanized and industrialized areas with important maritime, railway and road traffic. Industries are mainly represented by steel, cement works, and oil refineries. The maritime sector is becoming an even larger source of air pollution. Atmospheric NO x , SO 2 , O 3 levels and chemical analysis of airborne particulate matter were monitored in Dunkerque conurbation in 2005 and 2006. This study was included in the IRENI program. In low-pressure conditions, local pollutants are spread out far away the agglomeration, whereas, in high-pressure regimes, the atmospheric stability and sea-breezes allow an accumulation of pollutants over the urban zone. Size-resolved chemical analyses of particulate matter collected as function of the aerodynamic diameter (D a ) were performed. Ions (Na + , NH 4 + , Cl - , NO 3 - , SO 4 2- ), metals (Fe, Zn, Pb, Cd,...) and organic fraction (EC, OC) are associated with sub- or/and super-micron particles. The size, morphology and chemical species of individual particles collected selectively in the 12O 3 , Fe 3 O 4 , PbO,... containing particles emitted in the Dunkerque harbour area and aged sea-salt aerosol particles (NaCl, NaNO 3 ,...) from long range transport of air masses. Thin organic coatings from natural and anthropogenic origin are observed on the particles by ToF-SIMS imaging. (author)

  12. Morphology, chemistry and distribution of neoformed spherulites in agricultural land affected by metallurgical point-source pollution

    Energy Technology Data Exchange (ETDEWEB)

    Leguedois, Sophie; Oort, Folkert van; Jongmans, Toine; Chevallier, Pierre

    2004-07-01

    Metal distribution patterns in superficial soil horizons of agricultural land affected by metallurgical point-source pollution were studied using optical and electron microscopy, synchrotron radiation and spectroscopy analyses. The site is located in northern France, at the center of a former entry lane to a bunker of World War II, temporarily paved with coarse industrial waste fragments and removed at the end of the war. Thin sections made from undisturbed soil samples from A and B horizons were studied. Optical microscopy revealed the occurrence of yellow micrometer-sized (Ap horizon) and red decamicrometer-sized spherulites (AB, B{sub 1}g horizons) as well as distinct distribution patterns. The chemical composition of the spherulites was dominated by Fe, Mn, Zn, Pb, Ca, and P. Comparison of calculated Zn stocks, both in the groundmass and in spherulites, showed a quasi-exclusive Zn accumulation in these neoformed features. Their formation was related to several factors: (i) liberation of metal elements due to weathering of waste products, (ii) Ca and P supply from fertilizing practices, (iii) co-precipitation of metal elements and Ca and P in a porous soil environment, after slow exudation of a supersaturated soil solution in more confined mineral media. - Metal spherulites may act as high metal-trapping mineral phases in polluted agricultural soils.

  13. A statistical intercomparison between 'urban' and 'rural' precipitation chemistry data from Greater Manchester and the two nearby secondary national network sites in the United Kingdom

    Energy Technology Data Exchange (ETDEWEB)

    Lee, D.S.; Longhurst, J.W.S. (Manchester Polytechnic, Manchester (United Kingdom). Acid Rain Information Centre, Dept. of Environmental and Graphical Studies)

    1992-11-01

    Precipitation chemistry data from a dense urban monitoring network in Greater Manchester, northwest England, were compared with interpolated values from the U.K. secondary national acid deposition monitoring network for the year 1988. Differences were found to be small. However, when data from individual sites from the Greater Manchester network were compared with data from the two nearest secondary national network sites, significant differences were found using simple and complex statistical analyses. Precipitation chemistry at rural sites could be similar to that at urban sites, but the sources of some ions were thought to be different. The synoptic-scale gradients of precipitation chemistry, as shown by the secondary national network, also accounted for some of the differences. 34 refs., 7 figs., 8 tabs.

  14. Trends in precipitation and streamwater chemistry in East Creek watershed in southwestern British Columbia, 1971–2008

    Directory of Open Access Journals (Sweden)

    Michael C. FELLER

    2010-08-01

    Full Text Available Bulk precipitation and streamwater in a small, undisturbed, forested watershed in southwestern British Columbia were sampled regularly and analyzed for dissolved chemical constituents from 1971 to 2008. Concentrations and fluxes of most chemicals in precipitation and streamwater have exhibited considerable yearly variation. Temporal trends, when they have occurred, have rarely been consistent for the entire 1972–2008 time period. Precipitation has exhibited a decline in electrical conductivity, a decline in NH4, inorganic-N, and total-N concentrations and fluxes since the 1980s, an increase in pH, a decline in acid H fluxes since ~1990, and a decrease in SO4 concentrations and fluxes from 1980 until the late 1990s. Streamwater has exhibited an increase in NO3 concentrations and fluxes until the late 1990s, an increase in pH and decrease in acid H fluxes since the early 1990s, a decrease in SO4 concentrations and fluxes from ~1980 until ~2000, and increases in Na and Cl concentrations and fluxes until ~2000. Critical precipitation SO4 and inorganic-N loads have probably been exceeded for most years. East Ck. watershed has continuously experienced net inflows of all forms of N and acid H, and net outflows of dissolved Si, Na, Mg, and Ca. Net inflows of inorganic forms of N and total-N have decreased since the early 1980s. Net acid H inflows have decreased since the early 1990s, while net Na and Cl outflows increased until ~2000. The contribution of nutrient cycling processes within the watershed to the changes is currently unknown.

  15. Analytical chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Chae, Myeong Hu; Lee, Hu Jun; Kim, Ha Seok

    1989-02-15

    This book give explanations on analytical chemistry with ten chapters, which deal with development of analytical chemistry, the theory of error with definition and classification, sample and treatment gravimetry on general process of gravimetry in aqueous solution and non-aqueous solution, precipitation titration about precipitation reaction and types, complexometry with summary and complex compound, oxidation-reduction equilibrium on electrode potential and potentiometric titration, solvent extraction and chromatograph and experiment with basic operation for chemical experiment.

  16. Analytical chemistry

    International Nuclear Information System (INIS)

    Chae, Myeong Hu; Lee, Hu Jun; Kim, Ha Seok

    1989-02-01

    This book give explanations on analytical chemistry with ten chapters, which deal with development of analytical chemistry, the theory of error with definition and classification, sample and treatment gravimetry on general process of gravimetry in aqueous solution and non-aqueous solution, precipitation titration about precipitation reaction and types, complexometry with summary and complex compound, oxidation-reduction equilibrium on electrode potential and potentiometric titration, solvent extraction and chromatograph and experiment with basic operation for chemical experiment.

  17. Soil chemistry and pollution study of a closed landfill site at Ampar Tenang, Selangor, Malaysia.

    Science.gov (United States)

    Mohd Adnan, Siti Nur Syahirah Binti; Yusoff, Sumiani; Piaw, Chua Yan

    2013-06-01

    A total of 20 landfills are located in State of Selangor, Malaysia. This includes the Ampar Tenang landfill site, which was closed on 26 January 2010. It was reported that the landfill has been upgraded to a level I type of sanitary classification. However, the dumpsite area is not being covered according to the classification. In addition, municipal solid waste was dumped directly on top of the unlined natural alluvium formation. This does not only contaminate surface and subsurface soils, but also initiates the potential risk of groundwater pollution. Based on previous studies, the Ampar Tenang soil has been proven to no longer be capable of preventing pollution migration. In this study, metal concentrations of soil samples up to 30 m depth were analyzed based on statistical analysis. It is very significant because research of this type has not been carried out before. The subsurface soils were significantly polluted by arsenic (As), lead (Pb), iron (Fe), copper (Cu) and aluminium (Al). As and Pb exceeded the safe limit values of 5.90 mg/kg and 31.00 mg/kg, respectively, based on Provincial Sediment Quality Guidelines for Metals and the Interim Sediment Quality Values. Furthermore, only Cu concentrations showed a significantly decreasing trend with increasing depth. Most metals were found on clay-type soils based on the cluster analysis method. Moreover, the analysis also differentiates two clusters: cluster I-Pb, As, zinc, Cu, manganese, calcium, sodium, magnesium, potassium and Fe; cluster II-Al. Different clustering may suggest a different contamination source of metals.

  18. Effect of industrial dust on precipitation chemistry in the Czech Republic (Central Europe) from 1850 to 2013.

    Czech Academy of Sciences Publication Activity Database

    Kopáček, Jiří; Hejzlar, Josef; Krám, P.; Oulehle, F.; Posch, M.

    2016-01-01

    Roč. 103, October (2016), s. 30-37 ISSN 0043-1354 R&D Projects: GA ČR(CZ) GA14-09231S; GA ČR(CZ) GA15-04034S Institutional support: RVO:60077344 Keywords : sulphate * nitrate * chloride * ammonium * base cations * pH * Czech Republic Subject RIV: DI - Air Pollution ; Quality Impact factor: 6.942, year: 2016

  19. Land-based sources of pollution and environmental quality of Weija ...

    African Journals Online (AJOL)

    A survey of land-based sources of pollution was undertaken in the catchment area of Weija Lake. Activities that may influence the quality of the environment, and the sources, amounts and effects of the pollution of the water body were assessed. Water and precipitation chemistry showed that Na:Ca (0.48) and Na:K (2.0) ...

  20. Feedbacks between air pollution and weather, part 2: Effects on chemistry

    Science.gov (United States)

    Makar, P. A.; Gong, W.; Hogrefe, C.; Zhang, Y.; Curci, G.; Žabkar, R.; Milbrandt, J.; Im, U.; Balzarini, A.; Baró, R.; Bianconi, R.; Cheung, P.; Forkel, R.; Gravel, S.; Hirtl, M.; Honzak, L.; Hou, A.; Jiménez-Guerrero, P.; Langer, M.; Moran, M. D.; Pabla, B.; Pérez, J. L.; Pirovano, G.; San José, R.; Tuccella, P.; Werhahn, J.; Zhang, J.; Galmarini, S.

    2015-08-01

    Fully-coupled air-quality models running in ;feedback; and ;no-feedback; configurations were compared against each other and observation network data as part of Phase 2 of the Air Quality Model Evaluation International Initiative. In the ;no-feedback; mode, interactions between meteorology and chemistry through the aerosol direct and indirect effects were disabled, with the models reverting to climatologies of aerosol properties, or a no-aerosol weather simulation, while in the ;feedback; mode, the model-generated aerosols were allowed to modify the models' radiative transfer and/or cloud formation processes. Annual simulations with and without feedbacks were conducted for domains in North America for the years 2006 and 2010, and for Europe for the year 2010. Comparisons against observations via annual statistics show model-to-model variation in performance is greater than the within-model variation associated with feedbacks. However, during the summer and during intense emission events such as the Russian forest fires of 2010, feedbacks have a significant impact on the chemical predictions of the models. The aerosol indirect effect was usually found to dominate feedbacks compared to the direct effect. The impacts of direct and indirect effects were often shown to be in competition, for predictions of ozone, particulate matter and other species. Feedbacks were shown to result in local and regional shifts of ozone-forming chemical regime, between NOx- and VOC-limited environments. Feedbacks were shown to have a substantial influence on biogenic hydrocarbon emissions and concentrations: North American simulations incorporating both feedbacks resulted in summer average isoprene concentration decreases of up to 10%, while European direct effect simulations during the Russian forest fire period resulted in grid average isoprene changes of -5 to +12.5%. The atmospheric transport and chemistry of large emitting sources such as plumes from forest fires and large cities

  1. Effect of Microstructure and Alloy Chemistry on Hydrogen Embrittlement of Precipitation-Hardened Ni-Based Alloys

    Science.gov (United States)

    Obasi, G. C.; Zhang, Z.; Sampath, D.; Morana, Roberto; Akid, R.; Preuss, M.

    2018-04-01

    The sensitivity to hydrogen embrittlement (HE) has been studied in respect of precipitation size distributions in two nickel-based superalloys: Alloy 718 (UNS N07718) and Alloy 945X (UNS N09946). Quantitative microstructure analysis was carried out by the combination of scanning and transmission electron microscopy and energy dispersive x-ray spectroscopy (EDS). While Alloy 718 is mainly strengthened by γ″, and therefore readily forms intergranular δ phase, Alloy 945X has been designed to avoid δ formation by reducing Nb levels providing high strength through a combination of γ' and γ″. Slow strain rate tensile tests were carried out for different microstructural conditions in air and after cathodic hydrogen (H) charging. HE sensitivity was determined based on loss of elongation due to the H uptake in comparison to elongation to failure in air. Results showed that both alloys exhibited an elevated sensitivity to HE. Fracture surfaces of the H precharged material showed quasi-cleavage and transgranular cracks in the H-affected region, while ductile failure was observed toward the center of the sample. The crack origins observed on the H precharged samples exhibited quasi-cleavage with slip traces at high magnification. The sensitivity is slightly reduced for Alloy 718, by coarsening γ″ and reducing the overall strength of the alloy. However, on further coarsening of γ″, which promotes continuous decoration of grain boundaries with δ phase, the embrittlement index rose again indicating a change of hydrogen embrittlement mechanism from hydrogen-enhanced local plasticity (HELP) to hydrogen-enhanced decohesion embrittlement (HEDE). In contrast, Alloy 945X displayed a strong correlation between strength, based on precipitation size and embrittlement index, due to the absence of any significant formation of δ phase for the investigated microstructures. For the given test parameters, Alloy 945X did not display any reduced sensitivity to HE compared with

  2. The combined use of MODFLOW and precipitation-runoff modeling to simulate groundwater flow in a diffuse-pollution prone watershed.

    Science.gov (United States)

    Elçi, A; Karadaş, D; Fistikoğlu, O

    2010-01-01

    A numerical modeling case study of groundwater flow in a diffuse pollution prone area is presented. The study area is located within the metropolitan borders of the city of Izmir, Turkey. This groundwater flow model was unconventional in the application since the groundwater recharge parameter in the model was estimated using a lumped, transient water-budget based precipitation-runoff model that was executed independent of the groundwater flow model. The recharge rate obtained from the calibrated precipitation-runoff model was used as input to the groundwater flow model, which was eventually calibrated to measured water table elevations. Overall, the flow model results were consistent with field observations and model statistics were satisfactory. Water budget results of the model revealed that groundwater recharge comprised about 20% of the total water input for the entire study area. Recharge was the second largest component in the budget after leakage from streams into the subsurface. It was concluded that the modeling results can be further used as input for contaminant transport modeling studies in order to evaluate the vulnerability of water resources of the study area to diffuse pollution.

  3. Observational Insights into N2O5 Heterogeneous Chemistry: Influencing Factors and Contribution to Wintertime Air Pollution

    Science.gov (United States)

    McDuffie, E. E.; Fibiger, D. L.; Womack, C.; Dube, W. P.; Lopez-Hilfiker, F.; Goldberger, L.; Thornton, J. A.; Shah, V.; Jaegle, L.; Guo, H.; Weber, R. J.; Schroder, J. C.; Campuzano Jost, P.; Jimenez, J. L.; Franchin, A.; Middlebrook, A. M.; Baasandorj, M.; Brown, S. S.

    2017-12-01

    Chemical mechanisms that underlie wintertime air pollution, including tropospheric ozone and aerosol nitrate, are poorly characterized. Due to colder temperatures and fewer hours of solar radiation, nocturnal heterogeneous uptake of N2O5 plays a relatively larger role during wintertime in controlling the oxidation of NOx (=NO+NO2) and its influence on ozone and soluble nitrate. After uptake to aerosol, N2O5 can act as both a nocturnal NOx reservoir and sink depending on the partitioning between its nitric acid and photo labile, ClNO2 reaction products. In addition, N2O5 itself can act as a NOx reservoir if the aerosol uptake coefficient is small. As a result, the nocturnal fate of N2O5 dictates the amount of NOx in an air parcel and the subsequent formation of aerosol nitrate and following-day ozone. Models of winter air pollution therefore require accurate parameterization of the N2O5 uptake coefficient, as well as factors that control its magnitude and N2O5 product partitioning. There are currently only a small number of ambient N2O5 and ClNO2 observations during the winter season concurrent with measurements of relevant variables such as aerosol size distributions and composition. The Wintertime INvestigation of Transport, Emissions, and Reactivity (WINTER) campaign conducted 10 nighttime research flights with the NCAR C-130 over the eastern U.S. during February and March, 2015. The more recent Utah Wintertime Fine Particulate Study (UWFPS) conducted over 20 research flights with the NOAA twin otter aircraft during January-February 2017 in three mountain basins near and including Salt Lake City, Utah. The two campaigns were similarly instrumented and have provided the first aircraft observations of N2O5, ClNO2, and aerosol composition in the wintertime boundary layer in these urban-influenced regions. Analysis of heterogeneous chemistry under a wide range of real environmental conditions provides insight into the factors controlling the N2O5 uptake coefficient

  4. Biogenic emissions and biomass burning influences on the chemistry of the fogwater and stratiform precipitations in the African equatorial forest

    Science.gov (United States)

    Lacaux, J. P.; Loemba-Ndembi, J.; Lefeivre, B.; Cros, B.; Delmas, R.

    An automatic wet-only precipitation collector and a fogwater collector were operated in the coastal forest of equatorial Congo (Dimonika), for a complete seasonal cycle (November 1986-September 1987). Inorganic (Na +, K +, NH 4+, Ca 2+, NO 3-, Cl -, SO 42-) and organic (HCOO -, CH 3COO -) ions were determined in 33 stratiform rain events and nine fog events. With the raindrop size distributions, measured over a 1 year period (June 1988-June 1989) at the site of Enyelé in the Equatorial forest of Congo, were established the relationship between the liquid water content ( LWC in gm -3) and the rate of rainfall ( R in mm h -1) for the stratiform rains: LWC = 0.055 × R0.871 with a correlation coefficient of 0.98. Taking into account the dilution effect due to LWC, ionic concentrations of fogwater and stratiform precipitation are enriched during the dry season. In particular, K +, NO 3-, SO 42- and Ca 2+ are considerably enriched indicating the seasonal influence of the biomass burning due to savanna fires and terrigenous source from deserts of the Southern Hemisphere. Comparison of the chemical contents of fogwater—which mainly represents the local emission of the forest—and stratiform precipitation—which represent the air chemical content of the planetary boundary layer—during the dry season enabled us to show the following. Fog and rain with comparable chemical contents in mineral elements indicate a generalized contamination of the boundary layer by marine (Na +, Cl -), terrigenous (Ca 2+) and above all by biomass burning (K +, NO 3-, SO 42-) sources. The organic content (HCOO -, CH 3COO -) higher for the fogs than for rains, unexplainable by the dilution effect, has its source at a local level in the forest ecosystem. The estimation, from the organic content of fog and rain, of the gaseous concentrations of formic and acetic acids confirm the production of carboxylic acids measured in Amazonia during ABLE (for HCOOH : 510 ppt at canopy level and 170 ppt

  5. Factors controlling peat chemistry and vegetation composition in Sudbury peatlands after 30 years of pollution emission reductions

    International Nuclear Information System (INIS)

    Barrett, Sophie E.; Watmough, Shaun A.

    2015-01-01

    The objective of this research was to assess factors controlling peat and plant chemistry, and vegetation composition in 18 peatlands surrounding Sudbury after more than 30 years of large (>95%) pollution emission reductions. Sites closer to the main Copper Cliff smelter had more humified peat and the surface horizons were greatly enriched in copper (Cu) and nickel (Ni). Copper and Ni concentrations in peat were significantly correlated with that in the plant tissue of Chamaedaphne calyculata. The pH of peat was the strongest determining factor for species richness, diversity, and community composition, although percent vascular plant cover was strongly negatively correlated with surface Cu and Ni concentrations in peat. Sphagnum frequency was also negatively related to peat Cu and Ni concentrations indicating sites close to Copper Cliff smelter remain adversely impacted by industrial activities. - Highlights: • Surface peat in wetlands in Sudbury is contaminated with Cu and Ni. • The pH of peat is positively related to species richness and diversity. • Metal levels in peat is negatively related to vascular vegetation and Sphagnum cover. • Loss of Sphagnum at contaminated peatlands may impede recovery. - Sudbury peatlands remain impacted by industrial activities as indicated by elevated copper and nickel concentrations and diminished vascular plant cover and Sphagnum frequency.

  6. Influences of emission sources and meteorology on aerosol chemistry in a polluted urban environment: results from DISCOVER-AQ California

    Science.gov (United States)

    Young, D. E.; Kim, H.; Parworth, C.; Zhou, S.; Zhang, X.; Cappa, C. D.; Seco, R.; Kim, S.; Zhang, Q.

    2015-12-01

    The San Joaquin Valley (SJV) in California experiences persistent air quality problems associated with elevated particulate matter (PM) concentrations due to anthropogenic emissions, topography, and meteorological conditions. Thus it is important to unravel the various sources and processes that affect the physico-chemical properties of PM in order to better inform pollution abatement strategies and improve parameterizations in air quality models. positive matrix factorization (PMF) analysis of the AMS data: hydrocarbon-like OA (HOA; 9 % of total OA; O / C = 0.09) associated with local traffic, cooking OA (COA; 28 % of total OA; O / C = 0.19) associated with food cooking activities, two biomass burning OAs (BBOA1; 13 % of total OA; O / C = 0.33 and BBOA2; 20 % of total OA; O / C = 0.60) most likely associated with residential space heating from wood combustion, and semi-volatile oxygenated OA (SV-OOA; 16 % of total OA; O / C = 0.63) and low volatility oxygenated OA (LV-OOA; 24 % of total OA; O / C = 0.90) formed via chemical reactions in the atmosphere. Large differences in aerosol chemistry at Fresno were observed between the current campaign (winter 2013) and a~previous wintertime campaign (winter 2010), most notably that PM1 concentrations were nearly three times higher in 2013 than in 2010. These variations were attributed to differences in the meteorological conditions, which influenced primary emissions and secondary aerosol formation. In particular, COA and BBOA concentrations were greater in 2013 than 2010, where colder temperatures in 2013 likely resulted in increased biomass burning activities. The influence from a nighttime formed residual layer that mixed down in the morning was found to be much more intense in 2013 than 2010, leading to sharp increases in ground-level concentrations of secondary aerosol species including nitrate, sulfate, and OOA, in the morning between 08:00 to 12:00 PST. This is an indication that nighttime chemistry might also be

  7. Precipitation Chemistry and Occurrence of Acid Rain over the Oil-Producing Niger Delta Region of Nigeria

    Directory of Open Access Journals (Sweden)

    John Kanayo Chukwu Nduka

    2010-01-01

    Full Text Available This study investigated the nitrate, sulfate, total dissolved solid (TDS, electrical conductivity, total hardness (TH, and bicarbonates of rainwater samples collected from Warri and Port Harcourt between April–June, July–August, and September–October of 2005 and 2006 to depict onset of rainy season, mid-rainy season, and end of rainy season for the two major crude oil–producing cities of the Niger Delta region of Nigeria (although Port Harcourt is also noted for non-oil manufacturing industries. The same was done in Awka, a non-oil producing city in the hinterland of southeastern Nigeria. In each of the cities, rain samples were collected from three points in a triangular equilibrium using a clean plastic basin fastened to a table 2 m above ground level and 115 m away from tall buildings and trees. The parameters were determined after filtering, using their respective standard methods. Averages of 1.50, 1.81, 1.13 and 2.14, 1.50, 1.86 mg/l of nitrate for April–June, July–August, and September–October were recorded for Warri in 2005 and 2006, respectively. While 15.21, 3.23, 22.31 and 20.89, 9.96, and 14.27 mg/l were recorded in Port Harcourt. Sulfate levels for Warri and Port Harcourt for the same periods are follows: 1.38, 1.88, 1.06, 1.50, 1.43, 1.50 and 2.64, 1.15, 5.88, 4.73, 1.90, 1.55 mg/l, respectively. Nitrate levels were higher than sulfate. Other parameters include TDS (5.44, 4.79, 3.30 and 7.63, 3.69, 2.56 mg/l for Warri in 2005 and 2006; 12.57, 2.07, 25.214 and 28.87, 6.73, 7.80 mg/l for Port Harcourt for the same periods. Other parameters also varied in that order for the 2 years in same cities. Crude oil exploration and gas flaring in the Niger Delta, and multiplicity of cottage industries in Awka, impacted on the inorganic ion pollution of the rainwater. This may have public health implications in the region.

  8. Marine chemistry, fish / shell-fish surveys, benthic organisms, and marine toxic substances and pollutants data from current meter and other instruments in the Gulf of Mexico from 1993-01-26 to 1994-06-13 (NODC Accession 9500088)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Marine chemistry, fish / shell-fish surveys, benthic organisms, and marine toxic substances and pollutants data were collected using current meter and other...

  9. Comparison of Land-Use Regression Modeling with Dispersion and Chemistry Transport Modeling to Assign Air Pollution Concentrations within the Ruhr Area

    Directory of Open Access Journals (Sweden)

    Frauke Hennig

    2016-03-01

    Full Text Available Two commonly used models to assess air pollution concentration for investigating health effects of air pollution in epidemiological studies are Land Use Regression (LUR models and Dispersion and Chemistry Transport Models (DCTM. Both modeling approaches have been applied in the Ruhr area, Germany, a location where multiple cohort studies are being conducted. Application of these different modelling approaches leads to differences in exposure estimation and interpretation due to the specific characteristics of each model. We aimed to compare both model approaches by means of their respective aims, modeling characteristics, validation, temporal and spatial resolution, and agreement of residential exposure estimation, referring to the air pollutants PM2.5, PM10, and NO2. Residential exposure referred to air pollution exposure at residences of participants of the Heinz Nixdorf Recall Study, located in the Ruhr area. The point-specific ESCAPE (European Study of Cohorts on Air Pollution Effects-LUR aims to temporally estimate stable long-term exposure to local, mostly traffic-related air pollution with respect to very small-scale spatial variations (≤100 m. In contrast, the EURAD (European Air Pollution Dispersion-CTM aims to estimate a time-varying average air pollutant concentration in a small area (i.e., 1 km2, taking into account a range of major sources, e.g., traffic, industry, meteorological conditions, and transport. Overall agreement between EURAD-CTM and ESCAPE-LUR was weak to moderate on a residential basis. Restricting EURAD-CTM to sources of local traffic only, respective agreement was good. The possibility of combining the strengths of both applications will be the next step to enhance exposure assessment.

  10. Study of Chinese pollution with the 3D regional chemistry transport CHIMERE model and remote sensing observations, with a focus on mineral dust impacts

    Science.gov (United States)

    Lachatre, Mathieu; Foret, Gilles; Beekmann, Matthias; Cheiney, Audrey; Dufour, Gaëlle; Laurent, Benoit; Cuesta, Juan

    2017-04-01

    Since the end of the 20th century, China has observed important growth in numerous sectors. China's Gross Domestic Product (GDP) has been multiply by 4 during the 2000-2010 decade (National Bureau of Statistics of China), mostly because of the industry's growth. These evolutions have been accompanied by important increases of atmospheric pollutants emissions (Yinmin et al, Atmo Env, 2016). As a consequence and for about 10 years now, Chinese authorities have been working to reduce pollutant levels, because atmospheric pollution is a major health issue for Chinese population especially within cities, for which World Health Organisation's standards for major pollutants (Ozone, PM2.5, PM10) are often exceeded. Particles have multiple issues, as they impact on health and global warming. Their impacts will depend on their sources (primary or secondary pollutants) and natures (Particle size distribution, chemical composition…). Controlling particles loading is a complex task as their sources are various and dispersed on the Chinese territories: mineral dust can be emitted from Chinese deserts in large amount (Laurent et al., GPC, 2006), ammonia can be emitted from agriculture and livestock (Kang et al., ACP, 2016) and lots of urban primary pollutants can be emitted from urbanized areas. It is then necessary to work from a continental to local scales to understand more precisely pollution of urbanized areas. It is then mandatory to discriminate and quantify pollution sources and to estimate the impact of natural pollution and the major contributing sources. We propose here an approach based on a model and satellite observation synergy to estimate what controls Chinese pollution. We use the regional chemistry transport model CHIMERE (Menut et al., GMD, 2013) to simulate atmospheric pollutants concentrations. A large domain (72°E-145°E; 17.5°N-55°N), with a ¼°x¼° resolution is used to make multi-annual simulations. CHIMERE model include most of the pollutants

  11. Analytical chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jae Seong

    1993-02-15

    This book is comprised of nineteen chapters, which describes introduction of analytical chemistry, experimental error and statistics, chemistry equilibrium and solubility, gravimetric analysis with mechanism of precipitation, range and calculation of the result, volume analysis on general principle, sedimentation method on types and titration curve, acid base balance, acid base titration curve, complex and firing reaction, introduction of chemical electro analysis, acid-base titration curve, electrode and potentiometry, electrolysis and conductometry, voltammetry and polarographic spectrophotometry, atomic spectrometry, solvent extraction, chromatograph and experiments.

  12. Analytical chemistry

    International Nuclear Information System (INIS)

    Choi, Jae Seong

    1993-02-01

    This book is comprised of nineteen chapters, which describes introduction of analytical chemistry, experimental error and statistics, chemistry equilibrium and solubility, gravimetric analysis with mechanism of precipitation, range and calculation of the result, volume analysis on general principle, sedimentation method on types and titration curve, acid base balance, acid base titration curve, complex and firing reaction, introduction of chemical electro analysis, acid-base titration curve, electrode and potentiometry, electrolysis and conductometry, voltammetry and polarographic spectrophotometry, atomic spectrometry, solvent extraction, chromatograph and experiments.

  13. Impact of GHG warming on the mean and extreme loading of particulate matter pollution in a chemistry-climate model ensemble simulation

    Science.gov (United States)

    Xu, Y.; Lamarque, J. F.; Wu, X.

    2017-12-01

    Particulate matter with the diameter smaller than 2.5 micrometers (PM2.5) poses health threats to human populations. Regardless of efforts to regulate the pollution sources, it is unclear how climate change caused by greenhouse gases (GHGs) would affect PM2.5 levels. Using century-long ensemble simulations with Community Earth System Model 1 (CESM1), we show that, if the anthropogenic emissions would remain at the level in the year 2005, the global surface concentration and atmospheric column burden of sulfate, black carbon, and primary organic carbon would still increase by 5-10% at the end of 21st century (2090-2100) due to global warming alone. The decrease in the wet removal flux of PM2.5, despite an increase in global precipitation, is the primary cause for the increase in the PM2.5 column burden. Regionally over North America and East Asia, a shift of future precipitation toward more frequent heavy events contributes to weakened wet removal fluxes. Based on the daily model output, the frequency and intensity of extreme pollution events are also studied. We found that both stagnation frequency and rainfall changes serve to worsen extreme pollution in the future.

  14. Influences of emission sources and meteorology on aerosol chemistry in a polluted urban environment: results from DISCOVER-AQ California

    Directory of Open Access Journals (Sweden)

    D. E. Young

    2016-05-01

    Full Text Available The San Joaquin Valley (SJV in California experiences persistent air-quality problems associated with elevated particulate matter (PM concentrations due to anthropogenic emissions, topography, and meteorological conditions. Thus it is important to unravel the various sources and processes that affect the physicochemical properties of PM in order to better inform pollution abatement strategies and improve parameterizations in air-quality models. During January and February 2013, a ground supersite was installed at the Fresno–Garland California Air Resources Board (CARB monitoring station, where comprehensive, real-time measurements of PM and trace gases were performed using instruments including an Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS and an Ionicon proton transfer reaction time-of-flight mass spectrometer (PTR-TOF-MS as part of the NASA Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality (DISCOVER-AQ campaign. The average submicron aerosol (PM1 concentration was 31.0 µg m−3 and the total mass was dominated by organic aerosols (OA, 55 %, followed by ammonium nitrate (35 %. High PM pollution events were commonly associated with elevated OA concentrations, mostly from primary sources. Organic aerosols had average atomic oxygen-to-carbon (O / C, hydrogen-to-carbon (H / C, and nitrogen-to-carbon (N / C ratios of 0.42, 1.70, and 0.017, respectively. Six distinct sources of organic aerosol were identified from positive matrix factorization (PMF analysis of the AMS data: hydrocarbon-like OA (HOA; 9 % of total OA, O / C  =  0.09 associated with local traffic, cooking OA (COA; 18 % of total OA, O / C  =  0.19 associated with food cooking activities, two biomass burning OA (BBOA1: 13 % of total OA, O / C  =  0.33; BBOA2: 20 % of total OA, O / C  =  0.60 most likely

  15. Chemistry in Microfluidic Channels

    Science.gov (United States)

    Chia, Matthew C.; Sweeney, Christina M.; Odom, Teri W.

    2011-01-01

    General chemistry introduces principles such as acid-base chemistry, mixing, and precipitation that are usually demonstrated in bulk solutions. In this laboratory experiment, we describe how chemical reactions can be performed in a microfluidic channel to show advanced concepts such as laminar fluid flow and controlled precipitation. Three sets of…

  16. Impact of Santiago de Chile urban atmospheric pollution on anthropogenic trace elements enrichment in snow precipitation at Cerro Colorado, Central Andes

    Science.gov (United States)

    Cereceda-Balic, F.; Palomo-Marín, M. R.; Bernalte, E.; Vidal, V.; Christie, J.; Fadic, X.; Guevara, J. L.; Miro, C.; Pinilla Gil, E.

    2012-02-01

    Seasonal snow precipitation in the Andes mountain range is evaluated as an environmental indicator of the composition of atmospheric emissions in Santiago de Chile metropolitan area, by measuring a set of representative trace elements in snow samples by ICP-MS. Three late winter sampling campaigns (2003, 2008 and 2009) were conducted in three sampling areas around Cerro Colorado, a Central Andes mountain range sector NE of Santiago (36 km). Nevados de Chillán, a sector in The Andes located about 500 km south from the metropolitan area, was selected as a reference area. The experimental results at Cerro Colorado and Nevados de Chillán were compared with previously published data of fresh snow from remote and urban background sites. High snow concentrations of a range of anthropogenic marker elements were found at Cerro Colorado, probably derived from Santiago urban aerosol transport and deposition combined with the effect of mining and smelting activities in the area, whereas Nevados de Chillán levels roughly correspond to urban background areas. Enhanced concentrations in surface snow respect to deeper samples are discussed. Significant differences found between the 2003, 2008 and 2009 anthropogenic source markers profiles at Cerro Colorado sampling points were correlated with changes in emission sources at the city. The preliminary results obtained in this study, the first of this kind in the southern hemisphere, show promising use of snow precipitation in the Central Andes as a suitable matrix for receptor model studies aimed at identifying and quantifying pollution sources in Santiago de Chile.

  17. Indoor Chemistry

    DEFF Research Database (Denmark)

    Weschler, Charles J.; Carslaw, Nicola

    2018-01-01

    This review aims to encapsulate the importance, ubiquity, and complexity of indoor chemistry. We discuss the many sources of indoor air pollutants and summarize their chemical reactions in the air and on surfaces. We also summarize some of the known impacts of human occupants, who act as sources...... and sinks of indoor chemicals, and whose activities (e.g., cooking, cleaning, smoking) can lead to extremely high pollutant concentrations. As we begin to use increasingly sensitive and selective instrumentation indoors, we are learning more about chemistry in this relatively understudied environment....

  18. Method for modeling the deposition of sulfur by precipitation over regional scales

    International Nuclear Information System (INIS)

    Hicks, B.B.; Shannon, J.D.

    1979-01-01

    Radioactive fallout data suggest that the concentration of pollutants in rainfall, while highly variable, might be described on the average by about an inverse half-power dependence on the amount of precipitation. Recent measurements of sulfur concentrations in summer rainfall collected at Argonne National Laboratory tend to support this contention, as do preliminary results derived from operations of the DOE precipitation chemistry network. The concept is extended to develop a bulk removal rate for airborne total sulfur by precipitation for use in regional dispersion modeling

  19. Large eddy simulation of reactive pollutants in a deep urban street canyon: Coupling dynamics with O3-NOx-VOC chemistry.

    Science.gov (United States)

    Zhong, Jian; Cai, Xiao-Ming; Bloss, William James

    2017-05-01

    A large eddy simulation (LES) model coupled with O 3 -NO x -VOC chemistry is implemented to simulate the coupled effects of emissions, mixing and chemical pre-processing within an idealised deep (aspect ratio = 2) urban street canyon under a weak wind condition. Reactive pollutants exhibit significant spatial variations in the presence of two vertically aligned unsteady vortices formed in the canyon. Comparison of the LES results from two chemical schemes (simple NO x -O 3 chemistry and a more comprehensive Reduced Chemical Scheme (RCS) chemical mechanism) shows that the concentrations of NO 2 and O x inside the street canyon are enhanced by approximately 30-40% via OH/HO 2 chemistry. NO, NO x , O 3 , OH and HO 2 are chemically consumed, while NO 2 and O x (total oxidant) are chemically produced within the canyon environment. Within-canyon pre-processing increases oxidant fluxes from the canyon to the overlying boundary layer, and this effect is greater for deeper street canyons (as found in many traditional European urban centres) than shallower (lower aspect ratio) streets. There is clear evidence of distinct behaviours for emitted chemical species and entrained chemical species, and positive (or negative) values of intensities of segregations are found between pairs of species with similar (or opposite) behaviour. The simplified two-box model underestimated NO and O 3 levels, but overestimated NO 2 levels for both the lower and upper canyon compared with the more realistic LES-chemistry model. This suggests that the segregation effect due to incomplete mixing reduces the chemical conversion rate of NO to NO 2 . This study reveals the impacts of nonlinear O 3 -NO x -VOC photochemical processes in the incomplete mixing environment and provides a better understanding of the pre-processing of emissions within canyons, prior to their release to the urban boundary layer, through the coupling of street canyon dynamics and chemistry. Copyright © 2017 Elsevier Ltd

  20. Mercury Redox Chemistry in Waters of the Eastern Asian Seas: From Polluted Coast to Clean Open Ocean.

    Science.gov (United States)

    Ci, Zhijia; Zhang, Xiaoshan; Yin, Yongguang; Chen, Jinsheng; Wang, Shiwei

    2016-03-01

    We performed incubation experiments using seawaters from representative marine environments of the eastern Asian seas to determine the mercury (Hg) available for photoreduction (Hgr(II)), to investigate the Hg redox reaction kinetics, and to explore the effect of environmental factors and water chemistry on the Hg redox chemistry. Results show that Hgr(II) accounted for a considerable fraction of total Hg (THg) (%Hgr(II)/THg: 24.90 ± 10.55%, n = 27) and positively correlated with THg. Filtration decreased the Hgr(II) pool of waters with high suspended particulate matter (SPM). The positive linear relationships were found between pseudo-first order rate constants of gross Hg(II) photoreduction (kr) and gross Hg(0) photo-oxidation (ko) with photosynthetically active radiation (PAR). Under the condition of PAR of 1 m mol m(-2) s(-1), the kr were significantly (p < 0.05) lower than ko (kr/ko: 0.86 ± 0.22). The Hg(0) dark oxidation were significantly higher than the Hg(II) dark reduction. The Hg(II) dark reduction was positively correlated to THg, and the anaerobic condition favored the Hg(II) dark reduction. Filtration significantly influenced the Hg photoredox chemistry of waters with high SPM. UVB radiation was important for both Hg(II) photoreduction and Hg(0) photo-oxidation, and the role of other wavebands in photoinduced transformations of Hg varied with the water chemistry.

  1. Air pollution in the Benelux/Rhine-Ruhr area: Numerical simulations with a multi-scale regional chemistry-transport model

    Science.gov (United States)

    Memmesheimer, M.; Jakobs, H. J.; Wurzler, S.; Friese, E.; Piekorz, G.; Ebel, A.

    2009-04-01

    The Rhine-Ruhr area is a strongly industrialized region with about 10 Million inhabitants. It is one of the regions in Europe, which has the characteristics of a megacity with respect to population density, traffic, industry and environmental issues. The main centre of European steel production and the biggest inland port of the world is located in Duisburg, one of the major cities in the Rhine-Ruhr area. Together with the nearby urban agglomerations in the Benelux area including Brussels, Amsterdam and in particular Rotterdam as one of the most important sea-harbours of the world together with Singapore and Shanghai, it forms one of the regions in Europe heavily loaded with air pollutants as ozone, NO2 and particulate matter. Ammonia emissions outside the urban agglomerations but within the domain are also on a quite high level due to intense agricultural usage in Benelux, North-Rhine-Westphalia and lower Saxony. Therefore this area acts also as an important source region for gaseous precursors contributing to the formation of secondary particles in the atmosphere. The Benelux/Rhine-Ruhr area therefore has been selected within the framework of the recently established FP7 research project CityZen as one hot spot for detailed investigations of the past and current status of air pollution and its future development on different spatial and temporal scales. Some examples from numerical simulations with the regional multi-scale chemistry transport model EURAD for Central Europe and the Rhine-Ruhr area will be presented. The model calculates the transport, chemical transformations and deposition of trace constituents in the troposphere from the surface up to about 16 km using MM5 as meteorological driver, the RACM-MIM gas-phase chemistry and MADE-SORGAM for the treatment of particulate matter. Horizontal grid sizes are in the range of 100 km down to 1 km for heavily polluted urbanized areas within Benelux/Rhine-Ruhr. The planetary boundary layer is resolved by 15

  2. Morphology, chemistry and distribution of neoformed spherulites in agricultural land affected by metallurgical point-source pollution

    NARCIS (Netherlands)

    Leguedois, S.; Oort, van F.; Jongmans, A.G.; Chevalier, P.

    2004-01-01

    Metal distribution patterns in superficial soil horizons of agricultural land affected by metallurgical point-source pollution were studied using optical and electron microscopy, synchrotron radiation and spectroscopy analyses. The site is located in northern France, at the center of a former entry

  3. Chemistry and transport of pollution over the Gulf of Mexico and the Pacific: spring 2006 INTEX-B campaign overview and first results

    Directory of Open Access Journals (Sweden)

    H. B. Singh

    2009-04-01

    Full Text Available Intercontinental Chemical Transport Experiment-B (INTEX-B was a major NASA (Acronyms are provided in Appendix A. led multi-partner atmospheric field campaign completed in the spring of 2006 (http://cloud1.arc.nasa.gov/intex-b/. Its major objectives aimed at (i investigating the extent and persistence of the outflow of pollution from Mexico; (ii understanding transport and evolution of Asian pollution and implications for air quality and climate across western North America; and (iii validating space-borne observations of tropospheric composition. INTEX-B was performed in two phases. In its first phase (1–21 March, INTEX-B operated as part of the MILAGRO campaign with a focus on observations over Mexico and the Gulf of Mexico. In the second phase (17 April–15 May, the main INTEX-B focus was on trans-Pacific Asian pollution transport. Multiple airborne platforms carrying state of the art chemistry and radiation payloads were flown in concert with satellites and ground stations during the two phases of INTEX-B. Validation of Aura satellite instruments (TES, OMI, MLS, HIRDLS was a key objective within INTEX-B. Satellite products along with meteorological and 3-D chemical transport model forecasts were integrated into the flight planning process to allow targeted sampling of air parcels. Inter-comparisons were performed among and between aircraft payloads to quantify the accuracy of data and to create a unified data set. Pollution plumes were sampled over the Gulf of Mexico and the Pacific several days after downwind transport from source regions. Signatures of Asian pollution were routinely detected by INTEX-B aircraft, providing a valuable data set on gas and aerosol composition to test models and evaluate pathways of pollution transport and their impact on air quality and climate. This overview provides details about campaign implementation and a context within which the present

  4. Monitoring of long-range transported air pollutants and precipitation. Monitoring programme for forest damage. Abstract of annual reports 1996; Overvaaking av langtransportert forurenset luft og nedboer. Overvaakingsprogram for skogskader. Sammendrag av aarsrapporter 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    This report sums up the results for 1996 of two monitoring programmes: `` Norwegian Monitoring Programme for Long-Range Transported Air Pollutants`` and ``Norwegian forest monitoring programme``. The atmospheric pollution is monitored by measurements of chemical main components in the air and in precipitation. The effects of the pollutants on water quality are followed by monitoring of rivers, lakes and field research areas. The effects on fish are followed by regional investigations on benthic organisms, zooplankton and fish populations in rivers and lakes. Water chemical samples are taken each month from 16 rivers and acid material is monitored at seven field research areas. Samples are also taken from 200 lakes every autumn. The biological monitoring programme comprises fish in lakes and streams and benthic animals in lakes. The monitoring of forest damage uses three nation-wide areas from which registrations have been taken over a period of ten years. 28 figs., 6 tabs.

  5. The chemistry on a subnanometer scale of radiation-induced precipitation and segregation in fast-neutron irradiated tungsten-rhenium alloys

    International Nuclear Information System (INIS)

    Hershitz, R.; Seidman, D.N.

    1984-01-01

    The phenomena of radiation-induced precipitation and segregation have been investigated in W-10 at.% Re and W-25 at.% Re alloys, employing the atom-probe field-ion-microscope technique. The specimens had been irradiated to a fast-neutron fluence of approx.4x10 22 neutrons cm -2 (e>0.1 MeV) at 575, 625 and 675 deg C. This corresponds to 8.6 dpa and an average displacement rate, for the two year irradiation time of 1.4x10 -7 dpa s -1 . In the W-10 at.% Re alloy, coherent, semicoherent and possibly incoherent precipitates with the composition approx.WRe and a disc-shaped morphology -- one or two atomic planes thick -- were detected at a number density of approx.10 16 cm -3 , and a mean diameter of approx.57 A. In the W-25 at.% Re alloy the same precipitates with the composition approx.WRe 3 were detected at a number density of approx.10 17 cm -3 and a mean diameter of 40 A. The semicoherent WRe 3 precipitates were associated with 4 He atoms; that is, they may have been heterogeneously nucleated. None of the other precipitates were associated with either line or planar defects or with any impurity atoms. Therefore, a true homogeneous radiation-induced precipitation occurs in these alloys. In the W-25 at.% Re alloy a two dimensional WRe 3 phase has been observed at a grain boundary. The nucleation of both precipitates in the vicinity of displacement cascades might be produced by primary knock-on atoms. In both cases, the first step in the nucleation is due to the formation of tightly-bound mobile mixed dumbbells which react to form an immobile di-rhenium cluster. Point-defect mechanisms for all the other observations are also discussed

  6. Green chemistry: A tool in Pharmaceutical Chemistry

    OpenAIRE

    Smita Talaviya; Falguni Majumdar

    2012-01-01

    Green chemistry expresses an area of research developing from scientific discoveries about pollution awareness and it utilizes a set of principles that reduces or eliminates the use or generation of hazardous substances in all steps of particular synthesis or process. Chemists and medicinal scientists can greatly reduce the risk to human health and the environment by following all the valuable principles of green chemistry. The most simple and direct way to apply green chemistry in pharmaceut...

  7. Focal plane subsystem design and performance for atmospheric chemistry from geostationary orbit tropospheric emissions monitoring of pollution

    Science.gov (United States)

    Gilmore, A. S.; Philbrick, R. H.; Funderburg, J.

    2017-09-01

    Remote sensing of pollutants are enabled from a satellite in a geostationary orbit containing an imaging spectrometer encompassing the wavelength ranges of 290 - 490 nm and 540 - 740 nm. As the first of NASA's Earth Venture Instrument Program, the Tropospheric Emissions: Monitoring of Pollution (TEMPO) program will utilize this instrument to measure hourly air quality over a large portion of North America. The focal plane subsystem (FPS) contains two custom designed and critically aligned full frame transfer charge coupled devices (active area: 1028 x 2048, 18 μm) within a focal plane array package designed for radiation tolerance and space charging rejection. In addition, the FPS contains custom distributed focal plane electronics that provide all necessary clocks and biases to the sensors, receives all analog data from the sensors and performs 14 bit analog to digital conversion for upstream processing. Finally, the FPS encompasses custom low noise cables connecting the focal plane array and associated electronics. This paper discusses the design and performance of this novel focal plane subsystem with particular emphasis on the optical performance achieved including alignment, quantum efficiency, and modulation transfer function.

  8. Chemistry and physics of fogwater collection. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Jaeschke, W.; Enderle, K.H. (eds.)

    1988-01-01

    Increasing interest in the problems of air pollution and source receptor relationships has led to a significant expansion of knowledge in the field of atmospheric chemistry. In recent years the multiphase atmospheric chemistry was given great scholarly attention, and slogans like acid precipitation, dirty cloud or killer fog indicated these phenomena. The report describes results of collection and chemical analysis of fog water with emphasis or fog microphysics, of the heterogeneous atmospheric chemistry project in the Po-valley, of the development of the Great Dun Fell project, of the mountain cloud chemistry project in eastern U.S., of the design of fog water collectors and of the numerical study of the radiation fog event on October 10/11, 1982 in Albany, N.Y.

  9. Presentation of the EURODELTA III intercomparison exercise - evaluation of the chemistry transport models' performance on criteria pollutants and joint analysis with meteorology

    Science.gov (United States)

    Bessagnet, Bertrand; Pirovano, Guido; Mircea, Mihaela; Cuvelier, Cornelius; Aulinger, Armin; Calori, Giuseppe; Ciarelli, Giancarlo; Manders, Astrid; Stern, Rainer; Tsyro, Svetlana; García Vivanco, Marta; Thunis, Philippe; Pay, Maria-Teresa; Colette, Augustin; Couvidat, Florian; Meleux, Frédérik; Rouïl, Laurence; Ung, Anthony; Aksoyoglu, Sebnem; María Baldasano, José; Bieser, Johannes; Briganti, Gino; Cappelletti, Andrea; D'Isidoro, Massimo; Finardi, Sandro; Kranenburg, Richard; Silibello, Camillo; Carnevale, Claudio; Aas, Wenche; Dupont, Jean-Charles; Fagerli, Hilde; Gonzalez, Lucia; Menut, Laurent; Prévôt, André S. H.; Roberts, Pete; White, Les

    2016-10-01

    The EURODELTA III exercise has facilitated a comprehensive intercomparison and evaluation of chemistry transport model performances. Participating models performed calculations for four 1-month periods in different seasons in the years 2006 to 2009, allowing the influence of different meteorological conditions on model performances to be evaluated. The exercise was performed with strict requirements for the input data, with few exceptions. As a consequence, most of differences in the outputs will be attributed to the differences in model formulations of chemical and physical processes. The models were evaluated mainly for background rural stations in Europe. The performance was assessed in terms of bias, root mean square error and correlation with respect to the concentrations of air pollutants (NO2, O3, SO2, PM10 and PM2.5), as well as key meteorological variables. Though most of meteorological parameters were prescribed, some variables like the planetary boundary layer (PBL) height and the vertical diffusion coefficient were derived in the model preprocessors and can partly explain the spread in model results. In general, the daytime PBL height is underestimated by all models. The largest variability of predicted PBL is observed over the ocean and seas. For ozone, this study shows the importance of proper boundary conditions for accurate model calculations and then on the regime of the gas and particle chemistry. The models show similar and quite good performance for nitrogen dioxide, whereas they struggle to accurately reproduce measured sulfur dioxide concentrations (for which the agreement with observations is the poorest). In general, the models provide a close-to-observations map of particulate matter (PM2.5 and PM10) concentrations over Europe rather with correlations in the range 0.4-0.7 and a systematic underestimation reaching -10 µg m-3 for PM10. The highest concentrations are much more underestimated, particularly in wintertime. Further evaluation of

  10. Presentation of the EURODELTA III intercomparison exercise – evaluation of the chemistry transport models' performance on criteria pollutants and joint analysis with meteorology

    Directory of Open Access Journals (Sweden)

    B. Bessagnet

    2016-10-01

    Full Text Available The EURODELTA III exercise has facilitated a comprehensive intercomparison and evaluation of chemistry transport model performances. Participating models performed calculations for four 1-month periods in different seasons in the years 2006 to 2009, allowing the influence of different meteorological conditions on model performances to be evaluated. The exercise was performed with strict requirements for the input data, with few exceptions. As a consequence, most of differences in the outputs will be attributed to the differences in model formulations of chemical and physical processes. The models were evaluated mainly for background rural stations in Europe. The performance was assessed in terms of bias, root mean square error and correlation with respect to the concentrations of air pollutants (NO2, O3, SO2, PM10 and PM2.5, as well as key meteorological variables. Though most of meteorological parameters were prescribed, some variables like the planetary boundary layer (PBL height and the vertical diffusion coefficient were derived in the model preprocessors and can partly explain the spread in model results. In general, the daytime PBL height is underestimated by all models. The largest variability of predicted PBL is observed over the ocean and seas. For ozone, this study shows the importance of proper boundary conditions for accurate model calculations and then on the regime of the gas and particle chemistry. The models show similar and quite good performance for nitrogen dioxide, whereas they struggle to accurately reproduce measured sulfur dioxide concentrations (for which the agreement with observations is the poorest. In general, the models provide a close-to-observations map of particulate matter (PM2.5 and PM10 concentrations over Europe rather with correlations in the range 0.4–0.7 and a systematic underestimation reaching −10 µg m−3 for PM10. The highest concentrations are much more underestimated, particularly in

  11. Throughfall chemistry and canopy interactions in a Sitka spruce plantation sprayed with six different simulated polluted mist treatments

    International Nuclear Information System (INIS)

    Chiwa, M.; Crossley, A.; Sheppard, L.J.; Sakugawa, H.; Cape, J.N.

    2004-01-01

    Throughfall chemistry was studied in a mature Sitka spruce plantation in order to investigate canopy interactions, such as nitrogen absorption, cation leaching, and neutralization of rainfall passing through the canopy. The plantation had been exposed to six different simulated mist treatments including N (NH 4 NO 3 ) and S (H 2 SO 4 at pH 2.5) in four replicated blocks since 1996. Throughfall and rainfall were collected from May to September 2000. The results showed that 30-35% of the applied N was retained by the canopy. There were linear relationships between the loss of H + and increased K + , Mg 2+ and Ca 2+ deposition through the canopy. However these increases in K + , Mg 2+ and Ca 2+ deposition accounted for only about 50% of total neutralization of the acidity. The relationship between the anion deficits in throughfall and the loss of H + implied that weak organic acid anions were involved in the neutralization of the acidity in throughfall. - Weak organic acids may be involved in neutralizing acidity of throughfall

  12. Brazil-USA Collaborative Research: Modifications by Anthropogenic Pollution of the Natural Atmospheric Chemistry and Particle Microphysics of the Tropical Rain Forest During the GoAmazon Intensive Operating Periods (IOPs)

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Saewung [Univ. of California, Irvine, CA (United States)

    2017-08-01

    Manaus, a city of nearly two million people, represents an isolated urban area having a distinct urban pollution plume within the otherwise pristine Amazon Basin. The plume has high concentrations of oxides of nitrogen and sulfur, carbon monoxide, particle concentrations, and soot, among other pollutants. Critically, the distinct plume in the setting of the surrounding tropical rain forest serves as a natural laboratory to allow direct comparisons between periods of pollution influence to those of pristine conditions. The funded activity of this report is related to the Brazil-USA collaborative project during the two Intensive Operating Periods (wet season, 1 Feb - 31 Mar 2014; dry season, 15 Aug - 15 Oct 2014) of GoAmazon2014/5. The project addresses key science questions regarding the modification of the natural atmospheric chemistry and particle microphysics of the forest by present and future anthropogenic pollution.

  13. EPA Environmental Chemistry Laboratory

    Science.gov (United States)

    1993-01-01

    The Environmental Protection Agency's (EPA) Chemistry Laboratory (ECL) is a national program laboratory specializing in residue chemistry analysis under the jurisdiction of the EPA's Office of Pesticide Programs in Washington, D.C. At Stennis Space Center, the laboratory's work supports many federal anti-pollution laws. The laboratory analyzes environmental and human samples to determine the presence and amount of agricultural chemicals and related substances. Pictured, ECL chemists analyze environmental and human samples for the presence of pesticides and other pollutants.

  14. Environmental pollution

    International Nuclear Information System (INIS)

    Hanif, J.; Hanif, M.I.

    1997-01-01

    The third proceedings of National Symposium on Modern Trends in Contemporary Chemistry was held in Islamabad, Pakistan from February 24-26, 1997. In this symposium more than 220 scientists, engineers and technologist were registered from 11 universities, 17 research organisations and 8 non-governmental organisation including some commercial establishments. The symposium was divided into five technical sessions on hydro spheric pollution, atmospheric pollution, bio spheric pollution, lithospheric pollution and impact assessment and environmental education. Environmental and ecology are so interdependent that any change in the balance due to natural and man made cause may result in a disaster, flood, fire, earthquake, epidemic, population explosion etc. are the natural ways of unbalancing our ecosystem. The scope of this symposium includes: 1) Review the chemistry and the chemical techniques like polarography, coulometry, HPLC, GC-MS, NAA, XRF, AAS, AES etc. involved in the assessment monitoring and control of various pollutions. 2) Propose sampling, transportation, measurement and standardization procedures. 3) Collaboration in scientific data collection. 4) Mutual consultation for management of the pollution problem in a cost effective manner. 5) sharing knowledge and experience with various environmental protection groups both in public and private sector. (A.B.)

  15. Brazil-USA Collaborative Research: Modifications by Anthropogenic Pollution of the Natural Atmospheric Chemistry and Particle Microphysics of the Tropical Rain Forest During the GoAmazon Intensive Operating Periods (IOPs)

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez, Jose-Luis [Univ. of Colorado, Boulder, CO (United States); Day, Douglas A. [Univ. of Colorado, Boulder, CO (United States); Martin, Scot T. [Univ. of Colorado, Boulder, CO (United States); Kim, Saewung [Univ. of Colorado, Boulder, CO (United States); Smith, James [Univ. of Colorado, Boulder, CO (United States); Souza, Rodrigo [Univ. of Colorado, Boulder, CO (United States); Barbosa, Henry [Univ. of Colorado, Boulder, CO (United States)

    2017-08-04

    Manaus, a city of nearly two million people, represents an isolated urban area having a distinct urban pollution plume within the otherwise pristine Amazon Basin. The plume has high concentrations of oxides of nitrogen and sulfur, carbon monoxide, particle concentrations, and soot, among other pollutants. Critically, the distinct plume in the setting of the surrounding tropical rain forest serves as a natural laboratory to allow direct comparisons between periods of pollution influence to those of pristine conditions. The funded activity of this report is related to the Brazil-USA collaborative project during the two Intensive Operating Periods (wet season, 1 Feb - 31 Mar 2014; dry season, 15 Aug - 15 Oct 2014) of GoAmazon2014/5. The project addresses key science questions regarding the modification of the natural atmospheric chemistry and particle microphysics of the forest by present and future anthropogenic pollution. The first objective of the project was to understand and quantify the interactions of biogenic and anthropogenic emissions with respect to the production of secondary organic material. In clean conditions in the Amazon basin, secondary organic material dominates the diameter distribution of the submicron particles. How and why is the diameter distribution shifted by pollution? The second objective followed from the first in that, although the diameter distribution is dominated by secondary organic material, the actual source of new particle production remains uncertain (i.e., the number concentration). The second objective was to test the hypothesis that new particles under natural conditions are produced as a result of evaporation of primary particles emitted by fungal spores as well as to investigate any shifts in this mechanism under pollution conditions, e.g., in consequence to the high concentrations of SO2 in the pollution plume. Combined, the number-diameter distribution is the key connection to upscaling to the effects of aerosol

  16. Precipitation and measurements of precipitation

    NARCIS (Netherlands)

    Schmidt, F.H.; Bruin, H.A.R. de; Attmannspacher, W.; Harrold, T.W.; Kraijenhoff van de Leur, D.A.

    1977-01-01

    In Western Europe, precipitation is normal phenomenon; it is of importance to all aspects of society, particularly to agriculture, in cattle breeding and, of course, it is a subject of hydrological research. Precipitation is an essential part in the hydrological cycle. How disastrous local

  17. Radiation chemistry

    International Nuclear Information System (INIS)

    Rodgers, F.; Rodgers, M.A.

    1987-01-01

    The contents of this book include: Interaction of ionizing radiation with matter; Primary products in radiation chemistry; Theoretical aspects of radiation chemistry; Theories of the solvated electron; The radiation chemistry of gases; Radiation chemistry of colloidal aggregates; Radiation chemistry of the alkali halides; Radiation chemistry of polymers; Radiation chemistry of biopolymers; Radiation processing and sterilization; and Compound index

  18. Quantitative analysis chemistry

    International Nuclear Information System (INIS)

    Ko, Wansuk; Lee, Choongyoung; Jun, Kwangsik; Hwang, Taeksung

    1995-02-01

    This book is about quantitative analysis chemistry. It is divided into ten chapters, which deal with the basic conception of material with the meaning of analysis chemistry and SI units, chemical equilibrium, basic preparation for quantitative analysis, introduction of volumetric analysis, acid-base titration of outline and experiment examples, chelate titration, oxidation-reduction titration with introduction, titration curve, and diazotization titration, precipitation titration, electrometric titration and quantitative analysis.

  19. Journal of Applied Chemistry and Agricultural Research: Submissions

    African Journals Online (AJOL)

    Journal of Applied Chemistry and Agricultural Research: Submissions ... and water quality (pollution studies), phyisco-chemical properties of naturally occurring products, colloid chemistry, nutritional chemistry and metallurgy. ... For example:

  20. Green chemistry

    International Nuclear Information System (INIS)

    Warner, John C.; Cannon, Amy S.; Dye, Kevin M.

    2004-01-01

    A grand challenge facing government, industry, and academia in the relationship of our technological society to the environment is reinventing the use of materials. To address this challenge, collaboration from an interdisciplinary group of stakeholders will be necessary. Traditionally, the approach to risk management of materials and chemicals has been through inerventions intended to reduce exposure to materials that are hazardous to health and the environment. In 1990, the Pollution Prevention Act encouraged a new tact-elimination of hazards at the source. An emerging approach to this grand challenge seeks to embed the diverse set of environmental perspectives and interests in the everyday practice of the people most responsible for using and creating new materials--chemists. The approach, which has come to be known as Green Chemistry, intends to eliminate intrinsic hazard itself, rather than focusing on reducing risk by minimizing exposure. This chapter addresses the representation of downstream environmental stakeholder interests in the upstream everyday practice that is reinventing chemistry and its material inputs, products, and waste as described in the '12 Principles of Green Chemistry'

  1. Precipitous Birth

    Directory of Open Access Journals (Sweden)

    Jennifer Yee

    2017-09-01

    Full Text Available Audience: This scenario was developed to educate emergency medicine residents on the management of a precipitous birth in the emergency department (ED. The case is also appropriate for teaching of medical students and advanced practice providers, as well as reviewing the principles of crisis resource management, teamwork, and communication. Introduction: Patients with precipitous birth require providers to manage two patients simultaneously with limited time and resources. Crisis resource management skills will be tested once baby is delivered, and the neonate will require assessment for potential neonatal resuscitation. Objectives: At the conclusion of the simulation session, learners will be able to manage women who have precipitous deliveries, as well as perform neonatal assessment and management. Method: This session was conducted using high-fidelity simulation, followed by a debriefing session and lecture on precipitous birth management and neonatal evaluation.

  2. TCA precipitation.

    Science.gov (United States)

    Koontz, Laura

    2014-01-01

    Trichloroacetic acid (TCA) precipitation of proteins is commonly used to concentrate protein samples or remove contaminants, including salts and detergents, prior to downstream applications such as SDS-PAGE or 2D-gels. TCA precipitation denatures the protein, so it should not be used if the protein must remain in its folded state (e.g., if you want to measure a biochemical activity of the protein). © 2014 Elsevier Inc. All rights reserved.

  3. STRONTIUM PRECIPITATION

    Science.gov (United States)

    McKenzie, T.R.

    1960-09-13

    A process is given for improving the precipitation of strontium from an aqueous phosphoric-acid-containing solution with nickel or cobalt ferrocyanide by simultaneously precipitating strontium or calcium phosphate. This is accomplished by adding to the ferrocyanide-containing solution calcium or strontium nitrate in a quantity to yield a concentration of from 0.004 to 0.03 and adjusting the pH of the solution to a value of above 8.

  4. Acid precipitation; an annotated bibliography

    Science.gov (United States)

    Wiltshire, Denise A.; Evans, Margaret L.

    1984-01-01

    This collection of 1660 bibliographies references on the causes and environmental effects of acidic atmospheric deposition was compiled from computerized literature searches of earth-science and chemistry data bases. Categories of information are (1) atmospheric chemistry (gases and aerosols), (2) precipitation chemistry, (3) transport and deposition (wet and dry), (4) aquatic environments (biological and hydrological), (5) terrestrial environments, (6) effects on materials and structures, (7) air and precipitation monitoring and data collection, and (8) modeling studies. References date from the late 1800 's through December 1981. The bibliography includes short summaries of most documents. Omitted are unpublished manuscripts, publications in press, master 's theses and doctoral dissertations, newspaper articles, and book reviews. Coauthors and subject indexes are included. (USGS)

  5. Outdoor air Pollution

    CSIR Research Space (South Africa)

    Forbes, PBC

    2016-07-01

    Full Text Available This chapter focuses on the air pollutants which are generally found in the troposphere and does not provide detail on specific areas where atmospheric pollutants and atmospheric chemistry may differ from that generally found, such as in the arctic...

  6. Hydrocarbons and air pollution

    International Nuclear Information System (INIS)

    Herz, O.

    1992-01-01

    This paper shows the influence of hydrocarbons vapors, emitted by transports or by volatile solvents using, on air pollution. Hydrocarbons are the principal precursors of photochemical pollution. After a brief introduction on atmospheric chemistry and photochemical reactions, the author describes the french prevention program against hydrocarbons emissions. In the last chapter, informations on international or european community programs for photochemical pollution study are given. 5 figs., 10 tabs

  7. Acidity of Scandinavian precipitation

    Energy Technology Data Exchange (ETDEWEB)

    Barrett, E; Bordin, G

    1955-01-01

    Data on the pH of the total monthly precipitation at stations of a Swedish network for sampling and chemical analysis of precipitation and atmospheric aerosols during the year July 1953 to June 1954 are presented and discussed, together with the pH data from the first two months of operation of a large pan-Scandinavian net. It is found that well-defined regions of acidity and alkalinity relative to the pH of water in equilibrium with atmospheric carbon dioxide exist, and that these regions persist to such an extent that the monthly deviations from the pattern of the annual mean pH at stations unaffected by local pollution show persistently high acidity, while inland northern stations show equally persistent alkalinity. Some possible reasons for the observed distributions are considered.

  8. Precipitation Matters

    Science.gov (United States)

    McDuffie, Thomas

    2007-01-01

    Although weather, including its role in the water cycle, is included in most elementary science programs, any further examination of raindrops and snowflakes is rare. Together rain and snow make up most of the precipitation that replenishes Earth's life-sustaining fresh water supply. When viewed individually, raindrops and snowflakes are quite…

  9. Impact of Asian Aerosols on Precipitation Over California: An Observational and Model Based Approach

    Science.gov (United States)

    Naeger, Aaron R.; Molthan, Andrew L.; Zavodsky, Bradley T.; Creamean, Jessie M.

    2015-01-01

    Dust and pollution emissions from Asia are often transported across the Pacific Ocean to over the western United States. Therefore, it is essential to fully understand the impact of these aerosols on clouds and precipitation forming over the eastern Pacific and western United States, especially during atmospheric river events that account for up to half of California's annual precipitation and can lead to widespread flooding. In order for numerical modeling simulations to accurately represent the present and future regional climate of the western United States, we must account for the aerosol-cloud-precipitation interactions associated with Asian dust and pollution aerosols. Therefore, we have constructed a detailed study utilizing multi-sensor satellite observations, NOAA-led field campaign measurements, and targeted numerical modeling studies where Asian aerosols interacted with cloud and precipitation processes over the western United States. In particular, we utilize aerosol optical depth retrievals from the NASA Moderate Resolution Imaging Spectroradiometer (MODIS), NOAA Geostationary Operational Environmental Satellite (GOES-11), and Japan Meteorological Agency (JMA) Multi-functional Transport Satellite (MTSAT) to effectively detect and monitor the trans-Pacific transport of Asian dust and pollution. The aerosol optical depth (AOD) retrievals are used in assimilating the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) in order to provide the model with an accurate representation of the aerosol spatial distribution across the Pacific. We conduct WRF-Chem model simulations of several cold-season atmospheric river events that interacted with Asian aerosols and brought significant precipitation over California during February-March 2011 when the NOAA CalWater field campaign was ongoing. The CalWater field campaign consisted of aircraft and surface measurements of aerosol and precipitation processes that help extensively validate our WRF

  10. A review of United States yellow cake precipitation practice

    International Nuclear Information System (INIS)

    Litz, J.E.; Coleman, R.B.

    1980-01-01

    The various process flowsheets used to produce concentrated uranium solutions are reviewed. The choices of flowsheets are affected by ore alkalinity, uranium mineralization, and the impurities solubilized during leaching. The techniques used to precipitate yellow cake from concentrated uranium solutions are reviewed. Consideration is given to precipitation chemistry, reagent requirements, and process equipment and costs for precipitation, dewatering, drying and calcining. (author)

  11. Bad chemistry

    OpenAIRE

    Petsko, Gregory A

    2004-01-01

    General chemistry courses haven't changed significantly in forty years. Because most basic chemistry students are premedical students, medical schools have enormous influence and could help us start all over again to create undergraduate chemistry education that works.

  12. The chemistry of the global atmosphere; International Symposium of the Commission for Atmospheric Chemistry and Global Pollution of IAMAP, 7th, Chamrousse, France, Sept. 5-11, 1990, Selected Papers

    Science.gov (United States)

    Buat-Menard, P. (Editor); Delmas, R. J. (Editor)

    1992-01-01

    Topics presented include the adsorption and reaction of trichlorofluoromethane on various particles, equilibria of the marine multiphase ammonia system, a novel ozone sensor for direct eddy flux measurements, and characterization of the carbonate content of atmospheric aerosols. Also presented are variations in heavy metals concentrations in Antarctic snows, sources of continental dust over Antarctica during the last glacial cycle, an inventory of anthropogenic emissions and air pollution in the USSR, and atmospheric nuclei in the remote free-troposphere.

  13. Biomedical Science, Unit I: Respiration in Health and Medicine. Respiratory Anatomy, Physiology and Pathology; The Behavior of Gases; Introductory Chemistry; and Air Pollution. Student Text. Revised Version, 1975.

    Science.gov (United States)

    Biomedical Interdisciplinary Curriculum Project, Berkeley, CA.

    This student text deals with the human respiratory system and its relation to the environment. Topics include the process of respiration, the relationship of air to diseases of the respiratory system, the chemical and physical properties of gases, the impact on air quality of human activities and the effect of this air pollution on health.…

  14. The slow birth of green chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Amato, I.

    1993-03-12

    Mainstream chemistry is beginning to look at environmental chemistry as an important solution to environmental problems. This can include research into developing cleaner-burning liquid fuels, cleaning up oil spills, or developing better process methods which engender less pollution, as opposed to previous practices of detecting pollutants without preventing their release to begin with. This article discusses the progress of this chemistry discipline, describes some of the ongoing research, and describes the future for environmental chemistry. An impetus for future growth will be generational change, as young scientists in training are beginning to push faculities into creating programs for environmental chemistry.

  15. Air pollution in the Slovak Republic, 2004

    International Nuclear Information System (INIS)

    Mitosinkova, M.; Kozakovic, L.; Zavodsky, D.; Sajtakova, E.; Szemesova, J.; Pukancikova, K.

    2006-01-01

    A report on air quality and contribution of individual sources on its pollution in the Slovak Republic in 2004 is presented. This report consists of two parts: (1) Pollutants part and (2) Emission part. Pollutants part is divided into the following chapters: Regional air pollution and quality of precipitation; Local air pollution; Atmospheric ozone. Emission part is divided into the following chapters: Inventory control of emissions and sources of pollution, Emission of greenhouse gases

  16. Air pollution in the Slovak Republic, 2003

    International Nuclear Information System (INIS)

    Mitosinkova, M.; Kozakovic, L.; Zavodsky, D.; Sajtakova, E.; Szemesova, J.; Pukancikova, K.

    2005-01-01

    A report on air quality and contribution of individual sources on its pollution in the Slovak Republic in 2003 is presented. This report consists of two parts: (1) Pollutants part and (2) Emission part. Pollutants part is divided into the following chapters: Regional air pollution and quality of of precipitation; Local air pollution; Atmospheric ozone. Emission part is divided into the following chapters: Inventory control of emissions and sources of pollution, Emission of greenhouse gases

  17. Complex chemistry

    International Nuclear Information System (INIS)

    Kim, Bong Gon; Kim, Jae Sang; Kim, Jin Eun; Lee, Boo Yeon

    2006-06-01

    This book introduces complex chemistry with ten chapters, which include development of complex chemistry on history coordination theory and Warner's coordination theory and new development of complex chemistry, nomenclature on complex with conception and define, chemical formula on coordination compound, symbol of stereochemistry, stereo structure and isomerism, electron structure and bond theory on complex, structure of complex like NMR and XAFS, balance and reaction on solution, an organo-metallic chemistry, biology inorganic chemistry, material chemistry of complex, design of complex and calculation chemistry.

  18. Mathematical Chemistry

    OpenAIRE

    Trinajstić, Nenad; Gutman, Ivan

    2002-01-01

    A brief description is given of the historical development of mathematics and chemistry. A path leading to the meeting of these two sciences is described. An attempt is made to define mathematical chemistry, and journals containing the term mathematical chemistry in their titles are noted. In conclusion, the statement is made that although chemistry is an experimental science aimed at preparing new compounds and materials, mathematics is very useful in chemistry, among other things, to produc...

  19. Study of atmospheric pollution scavenging. Eighteenth progress report

    Energy Technology Data Exchange (ETDEWEB)

    Semonin, R.G.; Bartlett, J.D.; Bowersox, V.C.; Gatz, D.F.; Naiman, D.Q.; Peden, M.E.; Stahlhut, R.K.; Stensland, G.J.

    1980-07-01

    The analysis of aerosol samples obtained in rural east-central Illinois reveals a seasonal maximum in SO/sub 4/ during May to July and a similar pattern for NH/sub 4/. The annual median SO/sub 4/ is about 1 to 1.5 ..mu..g/m/sup 3/. In contrast to these ions, NO/sub 3/ displays highest values in the cold season. Soil-related species (Ca, K) seem to maximize in relation to farm tillage and harvesting practices. The NO/sub 3/ in recent precipitation samples over the northeast US increased between 1 and 2 times the values observed in the mid-1950's. A case study from SCORE-78 suggests that all ion concentrations analyzed from sequentially collected samples decreased from the onset of rain to a minimum corresponding to the heaviest rain rates. Four groups of elements in 10 event rain samples were identified using factor analysis. The groups include soluble and insoluble crustal elements, soluble pollutant metals and sulfate, and insoluble pollutant metals. Utilizing the factor analysis approach, the St. Louis METROMEX precipitation chemistry data showed that the SO/sub 4/ deposition patterns group consistently with those of other soluble pollutants. Additional factor analysis efforts on the St. Louis rainwater data set revealed that soluble and insoluble concentrations of a given element have different deposition patterns suggesting that scavenging and/or precipitation formation processes dictate the patterns. An approach to managing the vast data base of rain chemistry used in the above studies is described. The software also examines the data for certain aspects of quality assurance. The procedures used to analyze ambient air filter samples are discussed.

  20. Particle Pollution

    Science.gov (United States)

    ... Your Health Particle Pollution Public Health Issues Particle Pollution Recommend on Facebook Tweet Share Compartir Particle pollution — ... see them in the air. Where does particle pollution come from? Particle pollution can come from two ...

  1. Acid precipitation literature review

    Energy Technology Data Exchange (ETDEWEB)

    Seip, H M; Andersen, B; Andersson, G; Hov, Oe; Kucera, V; Moseholm, L

    1986-01-01

    There is an increasing number of publications on acid deposition and related phenomena. Interest in these topics has also been reflected in a considerable number of meetings and conferences in this field. The largest of these in 1985 was the ''International Symposium on Acidic Precipitation'' (Muskoka, Ontario). Most work so far has been carried out in North America and Europe. There is, however, an increasing interest in obtaining a better picture of sensitive areas and possible acidification in other parts of the world. Anthropogenic SO/sub 2/ emissions have been estimated to be (in TgSyr/sup -1/): 2.4 (Africa), 4.1 (South America), 0.7 (Ocenia), and 18.3 (Asia). The largest increase during the last decade has been in Asia. Based on Studies of precipitation in remote areas it has been suggested that the natural background concentration for sulphate in many areas should be about 6 ..mu..eq 1/sup -1/. A new study of sulphate and nitrate in Greenland snow showed that both ions increased by a factor of about 2 from 1895 to 1978. The concentrations of SO/sub 2/ at Norwegian rural sites show a decreasing trend since late 1970s, while concentrations of sulphate in air show no clear trend. More reliable models for transformation, transport and deposition of chemicals are being developed, including three-dimensional grid models to describe episodes of elevated pollution levels lasting for a few days. Model calculations indicate that control of hydrocarbon (HC) emissions is much more efficient in reducing the ozone level in southern Scandinavia in episodes influenced by long-range transported pollutants than NO/sub x/ control of combined NO/sub x/ and HC control. 36 refs. (EG).

  2. E-Alerts: Environmental pollution and control (water pollution and control). E-mail newsletter

    International Nuclear Information System (INIS)

    1999-01-01

    Topics of discussion include the following: Pollution by municipal wastes, agricultural wastes, industrial wastes, mine wastes, radioactive contaminants; Chemistry and analysis of pollutants; Thermal pollution; Oil pollution; Control techniques and equipment; Sewage treatment; Industrial waste water pretreatment; Hydrology and limnology; Biological and ecological effects; Waste water reuse; Laws, legislation, and regulations; Public administration; Economics; Land use

  3. E-Alerts: Environmental pollution and control (water pollution and control). E-mail newsletter

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-04-01

    Topics of discussion include the following: Pollution by municipal wastes, agricultural wastes, industrial wastes, mine wastes, radioactive contaminants; Chemistry and analysis of pollutants; Thermal pollution; Oil pollution; Control techniques and equipment; Sewage treatment; Industrial waste water pretreatment; Hydrology and limnology; Biological and ecological effects; Waste water reuse; Laws, legislation, and regulations; Public administration; Economics; Land use.

  4. Chemistry of plutonium revealed

    International Nuclear Information System (INIS)

    Connick, R.E.

    1992-01-01

    In 1941 one goal of the Manhattan Project was to unravel the chemistry of the synthetic element plutonium as rapidly as possible. In this paper the work carried out at Berkeley from the spring of 1942 to the summer of 1945 is described briefly. The aqueous chemistry of plutonium is quite remarkable. Important insights were obtained from tracer experiments, but the full complexity was not revealed until macroscopic amounts (milligrams) became available. Because processes for separation from fission products were based on aqueous solutions, such solution chemistry was emphasized, particularly precipitation and oxidation-reduction behavior. The latter turned out to be unusually intricate when it was discovered that two more oxidation states existed in aqueous solution than had previously been suspected. Further, an equilibrium was rapidly established among the four aqueous oxidation states, while at the same time any three were not in equilibrium. These and other observations made while doing a crash study of a previously unknown element are reported

  5. Atmosphere physics and chemistry

    International Nuclear Information System (INIS)

    Delmas, R.; Megie, G.; Peuch, V.H.

    2005-10-01

    Since the 1970's, the awareness about the atmospheric pollution threat has led to a spectacular development of the researches on the complex interactions between the chemical composition of the atmosphere and the climate. This book makes a synthesis of the state-of-the-art in this very active domain of research. Content: introduction, atmosphere dynamics and transport, matter-radiation interaction and radiant transfer, physico-chemical processes, atmospheric aerosol and heterogenous chemistry, anthropic and natural emissions and deposition, stratospheric chemical system, tropospheric chemical system, polluted boundary layer, paleo-environments and ice archives, role of atmospheric chemistry in global changes, measurement principles and instruments, numerical modeling, experimental strategy, regulation and management of the atmospheric environment, index. (J.S.)

  6. A simple strategy to refine Cu{sub 2}O photocatalytic capacity for refractory pollutants removal: Roles of oxygen reduction and Fe(II) chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Ai-Yong, E-mail: ayzhang@hfut.edu.cn; He, Yuan-Yi; Lin, Tan; Huang, Nai-Hui; Xu, Qiao; Feng, Jing-Wei, E-mail: jingweifeng@hfut.edu.cn

    2017-05-15

    Highlights: • A simple strategy was proposed to improve Cu{sub 2}O photochemical performance. • The photocatalysis-driven Fenton was developed for advanced water treatment. • The novel system had superior performance under visible light irradiation. • The catalytic mechanisms of novel system were elucidated and clearly presented. - Abstract: Visible-light-driven photocatalysis is a promising technology for advanced water treatment, but it usually exhibits a low efficiency. Cu{sub 2}O is a low-cost semiconductor with narrow band gap, high absorption coefficient and suitable conduction band, but suffers from low charge mobility, poor quantum yield and weak catalytic performance. Herein, the Cu{sub 2}O catalytic capacity for refractory pollutants degradation is drastically improved by a simple and effective strategy. By virtue of the synergistic effects between photocatalysis and Fenton, a novel and efficient photocatalysis-driven Fenton system, PFC, is originally proposed and experimentally validated using Cu{sub 2}O/Nano-C hybrids. The synergistic PFC is highly Nano-C-dependent and exhibits a significant superiority for the removal of rhodamine B and p-nitrophenol, two typical refractory pollutants in wastewater. The PFC superiority is mainly attributed to: (1) the rapid photo-electron transfer driven by Schottky-like junction, (2) the selective O{sub 2} reduction mediated by semi-metallic Nano-C for efficient H{sub 2}O{sub 2} generation, (3) the specific H{sub 2}O{sub 2} activation and large ·OH generation catalyzed by Haber-Weiss Fenton mechanism, and (4) the accelerated Fe{sup 2+}/Fe{sup 3+} cycling and robust Fe{sup 2+} regeneration via two additional pathways. Our findings might provide a new chance to overcome the intrinsic challenges of both photocatalysis and Fenton, as well as develop novel technology for advanced water treatment.

  7. Chemistry Notes

    Science.gov (United States)

    School Science Review, 1976

    1976-01-01

    Described are eight chemistry experiments and demonstrations applicable to introductory chemistry courses. Activities include: measure of lattice enthalpy, Le Chatelier's principle, decarboxylation of soap, use of pocket calculators in pH measurement, and making nylon. (SL)

  8. Chemistry Dashboard

    Science.gov (United States)

    The Chemistry Dashboard is part of a suite of dashboards developed by EPA to help evaluate the safety of chemicals. The Chemistry Dashboard provides access to a variety of information on over 700,000 chemicals currently in use.

  9. Food chemistry. 2. ed.

    International Nuclear Information System (INIS)

    Baltes, W.

    1989-01-01

    This second edition of the textbook deals with all essential aspects of food chemistry. The revision improved in particular the chapters on food preservation, including irradiation of food, food additives, and pollutants and residues, including radionuclides. The chapter on the German legal regime for foodstuffs has been updated to cover the recent amendments of the law, and the information on processes applied in food technology has been largely enhanced. (VHE) With 153 figs., 78 tabs [de

  10. Combinatorial chemistry

    DEFF Research Database (Denmark)

    Nielsen, John

    1994-01-01

    An overview of combinatorial chemistry is presented. Combinatorial chemistry, sometimes referred to as `irrational drug design,' involves the generation of molecular diversity. The resulting chemical library is then screened for biologically active compounds.......An overview of combinatorial chemistry is presented. Combinatorial chemistry, sometimes referred to as `irrational drug design,' involves the generation of molecular diversity. The resulting chemical library is then screened for biologically active compounds....

  11. Positronium chemistry

    CERN Document Server

    Green, James

    1964-01-01

    Positronium Chemistry focuses on the methodologies, reactions, processes, and transformations involved in positronium chemistry. The publication first offers information on positrons and positronium and experimental methods, including mesonic atoms, angular correlation measurements, annihilation spectra, and statistical errors in delayed coincidence measurements. The text then ponders on positrons in gases and solids. The manuscript takes a look at the theoretical chemistry of positronium and positronium chemistry in gases. Topics include quenching, annihilation spectrum, delayed coincidence

  12. Monitoring of long-range transported air pollutants, Annual report for 2011; Overvaaking av langtransportert forurenset luft og nedboer. Atmosfaeriske tilfoersler, 2011

    Energy Technology Data Exchange (ETDEWEB)

    Aas, Wenche; Solberg, Sverre; Manoe, Stein; Yttri, Karl Espen

    2012-07-01

    This report presents the 2011 monitoring results from the rural air- and precipitation chemistry monitoring network in Norway. In 2011, main components in precipitation were measured at 15 sites. Trace elements were determined at four sites. Air concentrations of sulphur and nitrogen compounds were measured at six sites, and ozone concentrations at eight sites. Persistent organic pollutants and heavy metals in air are determined at three sites. Measurements of PM10 and PM2.5 mass are also determined at three sites, including measurements of organic and elemental carbon (OC and EC). An overview of the measurement programme is given in Appendix B2. (Author)

  13. Primary Investigation of the Preparation of Nanoparticles by Precipitation

    Czech Academy of Sciences Publication Activity Database

    Vaculíková, E.; Grünwaldová, Veronika; Král, V.; Dohnal, J.; Jampílek, J.

    2012-01-01

    Roč. 17, č. 9 (2012), s. 11067-11078 ISSN 1420-3049 Institutional support: RVO:61388980 Keywords : steroids * nanoparticles * precipitation * excipients * dynamic light scattering Subject RIV: CA - Inorganic Chemistry Impact factor: 2.428, year: 2012

  14. Composition of atmospheric precipitation. I. Nitrogen compounds

    Energy Technology Data Exchange (ETDEWEB)

    Eriksson, E

    1952-01-01

    The purpose of this paper is to present a survey of published data on chemical analysis of atmospheric precipitation to discuss different cycles proposed for inorganic compounds in atmospheric precipitation and, finally, to assess the importance of these compounds from different points of view. Investigations of rainwater with a view to determine atmospheric pollution in industrial areas are mentioned incidentally but no results are detailed.

  15. Forensic Chemistry

    Science.gov (United States)

    Bell, Suzanne

    2009-07-01

    Forensic chemistry is unique among chemical sciences in that its research, practice, and presentation must meet the needs of both the scientific and the legal communities. As such, forensic chemistry research is applied and derivative by nature and design, and it emphasizes metrology (the science of measurement) and validation. Forensic chemistry has moved away from its analytical roots and is incorporating a broader spectrum of chemical sciences. Existing forensic practices are being revisited as the purview of forensic chemistry extends outward from drug analysis and toxicology into such diverse areas as combustion chemistry, materials science, and pattern evidence.

  16. Impact of Amazonian deforestation on atmospheric chemistry

    NARCIS (Netherlands)

    Ganzeveld, L.N.; Lelieveld, J.

    2004-01-01

    A single-column chemistry and climate model has been used to study the impact of deforestation in the Amazon Basin on atmospheric chemistry. Over deforested areas, daytime ozone deposition generally decreases strongly except when surface wetness decreases through reduced precipitation, whereas

  17. Study of atmospheric pollution scavenging. Seventeenth progress report

    Energy Technology Data Exchange (ETDEWEB)

    Semonin, R.G.; Bartlett, J.; Gatz, D.F.; Peden, M.E.; Skowron, L.M.; Stensland, G.J.

    1979-07-01

    The continued study of historical precipitation chemistry, air quality, and emissions data shows that the nitrate concentrations in precipitation have increased over the past 20 years with little change in sulfate concentrations. An analysis of aerosol concentrations at MAP3S precipitation collection sites shows consistently higher elemental concentrations at urban Champaign, Illinois, than sites at Whiteface Mountain, New York, and rural Champaign. Scavenging ratios at Whiteface exceeded those obtained previously at St. Louis, Missouri, possibly due to mid-tropospheric long-range transport and differing synoptic situations. Factor analysis of 6 storms during METROMEX shows that different deposition patterns were found for the soluble and insoluble concentrations of the same element. This suggests different scavenging processes may be active for these fractions. Using METROMEX data, no correlation was found between pollutant source strength and the urban-related precipitation anomaly. Four different Nuclepore air filter setups were used to compare air concentrations of sulfate, nitrate, and ammonium. The sulfate comparison was good, but the large variability for nitrate and ammonium raise serious questions on the credibility of measurements using Nuclepore as the collection medium. The details of a case study of wet deposition from SCORE-78 are presented and shows the pollutant concentrations are more variable than the rainfall. A brief description of the progress on the SCORE-79 project is presented. The progress on acid rainfall studies shows that the high pH values in the Midwest in the mid-1950's were due in part to elevated concentrations of calcium and magnesium. A variety of model calculations are presented to show the effects of adjusting past data to currently observed values. Recent results of continuing research on ionic stability of precipitation samples are given.

  18. SHORT COMMUNICATION GREEN CHEMISTRY VOLUMETRIC ...

    African Journals Online (AJOL)

    Preferred Customer

    ... part of pharmaceutical chemistry, cosmetics, drug formulations, soaps, ... apparatus is safe for both the liquid state and precipitation titrations and even heating of ... The cost incurred with use of 50 mL burette, for a class of 40 students for the ...

  19. Effects of land-use changes and stormflow-detention basins on flooding and nonpoint-source pollution, in Irondequoit Creek basin, Monroe and Ontario counties, New York--application of a precipitation-runoff model

    Science.gov (United States)

    Coon, William F.; Johnson, Mark S.

    2005-01-01

    Urbanization of the 150-square-mile Irondequoit Creek basin in Monroe and Ontario Counties, N.Y., continues to spread southward and eastward from the City of Rochester, on the shore of Lake Ontario. Conversion of forested land to other uses over the past 40 years has increased to the extent that more than 50 percent of the basin is now developed. This expansion has increased flooding and impaired stream-water quality in the northern (downstream) half of the basin. A precipitation-runoff model of the Irondequoit Creek basin was developed with the model code HSPF (Hydrological Simulation Program--FORTRAN) to simulate the effects of land-use changes and stormflow-detention basins on flooding and nonpoint-source pollution on the basin. Model performance was evaluated through a combination of graphical comparisons and statistical tests, and indicated 'very good' agreement (mean error less than 10 percent) between observed and simulated daily and monthly streamflows, between observed and simulated monthly water temperatures, and between observed total suspended solids loads and simulated sediment loads. Agreement between monthly observed and simulated nutrient loads was 'very good' (mean error less than 15 percent) or 'good' (mean error between 15 and 25 percent). Results of model simulations indicated that peak flows and loads of sediment and total phosphorus would increase in a rural subbasin, where 10 percent of the basin was converted from forest and grassland to pervious and impervious developed areas. Subsequent simulation of a stormflow-detention basin at the mouth of this subbasin indicated that peak flows and constituent loads would decrease below those that were generated by the land-use-change scenario, and, in some cases, below those that were simulated by the original land-use scenario. Other results from model simulations of peak flows over a 30-year period (1970-2000), with and without simulation of 50-percent flow reductions at one existing and nine

  20. Precipitation composition and wet deposition temporal pattern in Central Serbia for the period from 1998 to 2004.

    Science.gov (United States)

    Golobocanin, D; Zujić, A; Milenković, A; Miljević, N

    2008-07-01

    Bulk samples collected on a daily basis at three principal meteorological stations in central Serbia were analyzed on chloride (Cl(-)), nitrate (NO(3)(-)), sulfate (SO(4)(2-)), sodium (Na(+)), ammonium (NH(4)(+)), potassium (K(+)), calcium (Ca(2+)), and magnesium (Mg(2+)) in addition to precipitation amount, pH and conductivity measurements over the period 1998-2004. The data were subjected to variety of analyses (linear regression, principal component analysis, time series analysis) to characterize precipitation chemistry in the study area. The most abundant ion was SO(2-)(4) with annual volume weighted mean concentration of 242 microeq L(-1). Neutralization of precipitation acidity occurs both as a result of the dissolution of alkaline compounds containing Ca(2+), Mg(2+), and K(+) as well as the absorption of ammonia. The ratio of SO(4)(2-)/NO(3)(-) was above 5, which indicated that the combustion process of low-grade domestic lignite for electricity generation from coal-fired thermal power plants was the main source of pollution in the investigated area. A considerable mean annual bulk wet deposition of SO(4)-S determined by precipitation amount and concentrations of sulfate in the precipitation was calculated to be 12-35 kg ha(-1).

  1. Precipitation Indices Low Countries

    Science.gov (United States)

    van Engelen, A. F. V.; Ynsen, F.; Buisman, J.; van der Schrier, G.

    2009-09-01

    (+2): Wide scale river flooding, marshy acres and meadows.-Farmers cope with poor harvests of hay, grains, fruit etc. resulting in famines.-Late grape harvests, poor yield quantity and quality of wine. Wet period (+1): High water levels cq discharges of major rivers, tributaries and brooks, local river floodings, marshy acres and meadows in the low lying areas.-Wearisome and hampered agriculture. Normal (0) Dry period (-1): Low water levels cq discharges of major rivers, tributaries and brooks. Some brooks may dry up.-Summer half year: local short of yield of grass, hay and other forage.-Summer half year: moor-, peat- and forest fires. Very dry period (-2): Very low water levels cq discharges of major rivers and tributaries. Brooks and wells dry up. Serious shortage of drinking water; especially in summer.-Major agricultural damage, shortage of water, mortality stock of cattle. Shortage of grain. Flour can not be produced due to water mills running out of water, shortage of bread, bread riots, famines.-Large scale forest and peat areas, resulting in serious air pollution. Town fires. By verifying the historical evidence on these criterions, a series of 5 step indices ranging from very dry to very wet for summer and winter half year of the Low Countries was obtained. Subsequently these indices series were compared with the instrumentally observed seasonal precipitation sums for De Bilt (1735-2008), which is considered to be representative for the Central Netherlands. For winter (Oct-March) and summer half year (Apr.-Sept.) the accumulated precipitation amounts are calculated; these amounts are approximately normally distributed. Based on this distribution, the cumulative frequency distribution is calculated. By tabulating the number of summers in the pre-instrumental period 1201-1750 for each of the drought classes, a distribution is calculated which is then related to the modern accumulated precipitation distribution. Assuming that the accumulated precipitation amount

  2. Organic chemistry

    International Nuclear Information System (INIS)

    2003-08-01

    This book with sixteen chapter explains organic chemistry on linkage isomerism such as alkane, cycloalkane, alkene, aromatic compounds, stereo selective isomerization, aromatic compounds, stereo selective isomerization, organic compounds, stereo selective isomerization, organic halogen compound, alcohol, ether, aldehyde and ketone, carboxylic acid, dicarboxylic acid, fat and detergent, amino, carbohydrate, amino acid and protein, nucleotide and nucleic acid and spectroscopy, a polymer and medical chemistry. Each chapter has introduction structure and characteristic and using of organic chemistry.

  3. Radiation chemistry

    Energy Technology Data Exchange (ETDEWEB)

    None

    1973-07-01

    Research progress is reported on radiation chemistry of heavy elements that includes the following topics: radiation chemistry of plutonium in nitric acid solutions (spectrophotometric analysis and gamma radiolysis of Pu(IV) and Pu(VI) in nitric acid solution); EPR studies of intermediates formed in radiolytic reactions with aqueous medium; two-phase radiolysis and its effect on the distribution coefficient of plutonium; and radiation chemistry of nitric acid. (DHM)

  4. Technetium chemistry

    International Nuclear Information System (INIS)

    Burns, C.; Bryan, J.; Cotton, F.; Ott, K.; Kubas, G.; Haefner, S.; Barrera, J.; Hall, K.; Burrell, A.

    1996-01-01

    Technetium chemistry is a young and developing field. Despite the limited knowledge of its chemistry, technetium is the workhorse for nuclear medicine. Technetium is also a significant environmental concern because it is formed as a byproduct of nuclear weapons production and fission-power generators. Development of new technetium radio-pharmaceuticals and effective environmental control depends strongly upon knowledge of basic technetium chemistry. The authors performed research into the basic coordination and organometallic chemistry of technetium and used this knowledge to address nuclear medicine and environmental applications. This is the final report of a three-year Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL)

  5. Chemistry Technology

    Data.gov (United States)

    Federal Laboratory Consortium — Chemistry technology experts at NCATS engage in a variety of innovative translational research activities, including:Design of bioactive small molecules.Development...

  6. Air pollution engineering

    Science.gov (United States)

    Maduna, Karolina; Tomašić, Vesna

    2017-11-01

    Air pollution is an environmental and a social problem which leads to a multitude of adverse effects on human health and standard of human life, state of the ecosystems and global change of climate. Air pollutants are emitted from natural, but mostly from anthropogenic sources and may be transported over long distances. Some air pollutants are extremely stable in the atmosphere and may accumulate in the environment and in the food chain, affecting human beings, animals and natural biodiversity. Obviously, air pollution is a complex problem that poses multiple challenges in terms of management and abatements of the pollutants emission. Effective approach to the problems of air pollution requires a good understanding of the sources that cause it, knowledge of air quality status and future trends as well as its impact on humans and ecosystems. This chapter deals with the complexities of the air pollution and presents an overview of different technical processes and equipment for air pollution control, as well as basic principles of their work. The problems of air protection as well as protection of other ecosystems can be solved only by the coordinated endeavors of various scientific and engineering disciplines, such as chemistry, physics, biology, medicine, chemical engineering and social sciences. The most important engineering contribution is mostly focused on development, design and operation of equipment for the abatement of harmful emissions into environment.

  7. American Chemical Society, Division of Environmental Chemistry

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    Separate abstracts were prepared for 161 papers of this divisional meeting for the US Department of Energy's Database. Main topics discussed included: acid rain mitigation - liming technologies and environmental considerations; biotechnology for wastewater treatment; environmental chemistry of lakes and reservoirs and pollution prevention and process analytical chemistry

  8. Current organic chemistry

    National Research Council Canada - National Science Library

    1997-01-01

    Provides in depth reviews on current progress in the fields of asymmetric synthesis, organometallic chemistry, bioorganic chemistry, heterocyclic chemistry, natural product chemistry, and analytical...

  9. Analytical chemistry experiment

    International Nuclear Information System (INIS)

    Park, Seung Jo; Paeng, Seong Gwan; Jang, Cheol Hyeon

    1992-08-01

    This book deals with analytical chemistry experiment with eight chapters. It explains general matters that require attention on experiment, handling of medicine with keep and class, the method for handling and glass devices, general control during experiment on heating, cooling, filtering, distillation and extraction and evaporation and dry, glass craft on purpose of the craft, how to cut glass tube and how to bend glass tube, volumetric analysis on neutralization titration and precipitation titration, gravimetric analysis on solubility product, filter and washing and microorganism experiment with necessary tool, sterilization disinfection incubation and appendixes.

  10. Marine pollution

    International Nuclear Information System (INIS)

    Albaiges, J.

    1989-01-01

    This book covers the following topics: Transport of marine pollutants; Transformation of pollutants in the marine environment; Biological effects of marine pollutants; Sources and transport of oil pollutants in the Persian Gulf; Trace metals and hydrocarbons in Syrian coastal waters; and Techniques for analysis of trace pollutants

  11. Nuclear chemistry

    International Nuclear Information System (INIS)

    Vertes, A.; Kiss, I.

    1987-01-01

    This book is an introduction to the application of nuclear science in modern chemistry. The first group of chapters discuss the basic phenomena and concepts of nuclear physics with emphasis on their relation to chemical problems, including the main properties and the composition of atomic nuclei, nuclear reactions, radioactive decay and interactions of radiation with matter. These chapters provide the basis for understanding the following chapters which encompass the wide scope of nuclear chemistry. The methods of the investigation of chemical structure based on the interaction of nuclear radiation with matter including positronium chemistry and other exotic atoms is elaborated in particular detail. Separate chapters are devoted to the use of radioactive tracers, the chemical consequences of nuclear processes (i.e. hot atom chemistry), radiation chemistry, isotope effects and their applications, and the operation of nuclear reactors

  12. Nuclear chemistry

    International Nuclear Information System (INIS)

    Vertes, A.; Kiss, I.

    1987-01-01

    This book is an introduction to the application of nuclear science in modern chemistry. The first group of chapters discuss the basic phenomena and concepts of nuclear physics with emphasis on their relation to chemical problems, including the main properties and the composition of atomic nuclei, nuclear reactions, radioactive decay and interactions of radiation with matter. These chapters provide the basis for understanding the following chapters which encompass the wide scope of nuclear chemistry. The methods of the investigation of chemical structure based on the interaction of nuclear radiation with matter including positronium chemistry and other exotic atoms is elaborated in particular detail. Separate chapters are devoted to the use of radioactive tracers, the chemical consequences of nuclear processes (i.e. hot atom chemistry), radiation chemistry, isotope effects and their applications, and the operation of nuclear reactors. (Auth.)

  13. Air pollution in the Slovak Republic, 2001

    International Nuclear Information System (INIS)

    Mitosinkova, M.; Kozakovic, L.; Zavodsky, D.; Sajtakova, E.; Mareckova, K.; Pukancikova, K.

    2003-01-01

    A report on air quality and contribution of individual sources on its pollution in the Slovak Republic in 2001 is presented. This report consists of two parts: (1) Ambient air and (2) Emission. Ambient air part is divided into the following chapters: Regional air pollution and quality of precipitation; Local air pollution; Atmospheric ozone. Emission part is divided into the following chapters: Emission and air pollution source inventory, Greenhouse gas emissions

  14. Water Pollution

    Science.gov (United States)

    Bowen, H. J. M.

    1975-01-01

    Deals with water pollution in the following categories: a global view, self purification, local pollution, difficulties in chemical analysis, and remedies for water pollution. Emphasizes the extent to which man's activities have modified the cycles of certain elements. (GS)

  15. Air Pollution

    Science.gov (United States)

    Air pollution is a mixture of solid particles and gases in the air. Car emissions, chemicals from factories, ... Ozone, a gas, is a major part of air pollution in cities. When ozone forms air pollution, it's ...

  16. Acidification of air and precipitation and its consequences on the natural environment

    Energy Technology Data Exchange (ETDEWEB)

    Oden, S

    1968-01-01

    Changes in the chemistry of the atmosphere were discussed using 15 years of data collected by a European sampling network, beginning in 1952. Sulfur content of air and precipitation were closely related to air pollution from cities and industry, as a result of increasing use of sulfurous fuels. A special study of the acidity of 600 lakes in western Scandinavia showed that between 1959 and 1967 pH values declined an average of 0.4 units. Acid precipitation will eventually acidify rivers. The change in pH will depend on the buffering capacity of the catchment area and other factors. Negative trends have already been noted. Acificiation threatens aquatic organisms as most cannot exist in water below pH 4.0. Certain valuable fish such as salmon are threatened at pH 5.5 and catches have begun to decline. Soils may also be affected if the supply of neutralizing substances declines. Decreased crop production and reduced forest growth rate may result. The balance of nature is disturbed by the present atmospheric pollution of sulfuric and other acids. (MDF)

  17. Precipitation Kinetics in a Nb-stabilized Ferritic Stainless Steel

    Science.gov (United States)

    Labonne, M.; Graux, A.; Cazottes, S.; Danoix, F.; Cuvilly, F.; Chassagne, F.; Perez, M.; Massardier, V.

    2017-08-01

    The precipitation occurring in a Nb-stabilized ferritic stainless steel, containing initially Nb(C, N) carbonitrides and Fe3Nb3X precipitates, was investigated during aging treatments performed between 923 K and 1163 K (650 °C and 890 °C) by combining different techniques, (thermoelectric power (TEP), scanning/transmission electron microscopy (SEM/TEM), and atom probe tomography (APT)), in order to determine the precipitation kinetics, the nature and morphology of the newly formed precipitates as well as the chemistry of the initial Fe3Nb3X precipitates, where X stands for C or N. The following composition was proposed for these precipitates: (Fe0.81 Cr0.19)3 (Nb0.85 Si0.08 Mo0.07)3 (N0.8 C0.2), highlighting the simultaneous presence of N and C in the precipitates. With regard to the precipitation in the investigated temperature range, two main phenomena, associated with a hardness decrease, were clearly identified: (i) the precipitation of Fe2Nb precipitates from the niobium initially present in solution or coming from the progressive dissolution of the Fe3Nb3X precipitates and (ii) the precipitation of the χ-phase at grain boundaries for longer aging times. From the TEP kinetics, a time-temperature-precipitation diagram has been proposed.

  18. Combustion chemistry - activities in the CHEK research programme

    Energy Technology Data Exchange (ETDEWEB)

    Dam-Johansen, K.; Johnsson, J.E.; Glarborg, P.; Frandsen, F.; Jensen, A.; Oestberg, M. [Technical Univ. of Denmark, Lyngby (Denmark). Dept. of Chemical Engineering

    1997-10-01

    The combustion chemistry in the oxidation of fossil fuels and biofuels determines together with mixing and heat transfer the required size of a furnace, the emission of gaseous pollutants, and the formation of ash and deposits on surfaces. This presentation describes technologies for solid fuels combustion and gives a summary of the fuels, the pollutant chemistry and the inorganic chemistry in combustion processes. Emphasis is put on the work carried out in the CHEC (Combustion and Harmful Emission Control) Research Programme. (orig.)

  19. Aerosol radiative effects on mesoscale cloud-precipitation variables over Northeast Asia during the MAPS-Seoul 2015 campaign

    Science.gov (United States)

    Park, Shin-Young; Lee, Hyo-Jung; Kang, Jeong-Eon; Lee, Taehyoung; Kim, Cheol-Hee

    2018-01-01

    The online model, Weather Research and Forecasting Model with Chemistry (WRF-Chem) is employed to interpret the effects of aerosol-cloud-precipitation interaction on mesoscale meteorological fields over Northeast Asia during the Megacity Air Pollution Study-Seoul (MAPS-Seoul) 2015 campaign. The MAPS-Seoul campaign is a pre-campaign of the Korea-United States Air Quality (KORUS-AQ) campaign conducted over the Korean Peninsula. We validated the WRF-Chem simulations during the campaign period, and analyzed aerosol-warm cloud interactions by diagnosing both aerosol direct, indirect, and total effects. The results demonstrated that aerosol directly decreased downward shortwave radiation up to -44% (-282 W m-2) for this period and subsequently increased downward longwave radiation up to +15% (∼52 W m-2) in the presence of low-level clouds along the thematic area. Aerosol increased cloud fraction indirectly up to ∼24% with the increases of both liquid water path and the droplet number mixing ratio. Precipitation properties were altered both directly and indirectly. Direct effects simply changed cloud-precipitation quantities via simple updraft process associated with perturbed radiation and temperature, while indirect effects mainly suppressed precipitation, but sometimes increased precipitation in the higher relative humidity atmosphere or near vapor-saturated condition. The total aerosol effects caused a time lag of the precipitation rate with the delayed onset time of up to 9 h. This implies the importance of aerosol effects in improving mesoscale precipitation rate prediction in the online approach in the presence of non-linear warm cloud.

  20. Quantum chemistry

    CERN Document Server

    Lowe, John P

    1993-01-01

    Praised for its appealing writing style and clear pedagogy, Lowe's Quantum Chemistry is now available in its Second Edition as a text for senior undergraduate- and graduate-level chemistry students. The book assumes little mathematical or physical sophistication and emphasizes an understanding of the techniques and results of quantum chemistry, thus enabling students to comprehend much of the current chemical literature in which quantum chemical methods or concepts are used as tools. The book begins with a six-chapter introduction of standard one-dimensional systems, the hydrogen atom,

  1. Study of air pollution scavenging. Fifteenth progress report. [Air pollution over St. Louis, Missouri and rural Illinois

    Energy Technology Data Exchange (ETDEWEB)

    Semonin, R.G.; Ackerman, B.; Gatz, D.F.; Rilberg, S.D.; Peden, M.E.; Stahlhut, R.K.; Stensland, G.J.

    1977-07-01

    Selected analyses of air and rainwater chemistry and meteorological data are presented as part of the final efforts on the 5-year METROMEX study. The size characterization, air concentration, and source identification of aerosols over and near St. Louis are related to the urban-industrial activities of the metropolitan area. The precipitation studies are comprised of a comparison of chemical analyses of simulated rain samples between several laboratories, including the Survey. The results showed that the analytical technique used by the Survey for the chemical analysis of the METROMEX samples is excellent for increasing confidence in the published data. Other precipitation analyses are directed toward the acid rain problem as demonstrated by historical and current measurements in Illinois. The meteorological investigations consist of analysis of diurnal temperature and moisture cycles at urban and rural sites which relates to the development of the planetary boundary layer (PBL) as perturbed by the city. The three-dimensional character of the PBL is also presented as determined by the radiosonde operations during METROMEX. Finally, the technique to calculate three-dimensional trajectories of air motion using the numerous pilot balloon observations acquired during the project is presented. These data are essential for the full interpretation of the air and rain chemistry observations, and the development of empirical models of pollutant scavenging.

  2. Radioactivity precipitation Sr-90 and Cs-137 in Plock

    International Nuclear Information System (INIS)

    Flakiewicz, W.; Majkowska, I.; Bonkowski, J.

    1986-01-01

    Methods of research and results for beta-activity measurements of precipitation in 1977-1983 with regard to Sr-90, Cs-137 - are presented. Climatic changes caused by big industrial plant, conditions of pollution propagation in atmosphere, parameters of pollution load of Plock region are described. 11 refs., 6 figs., 5 tabs. (author)

  3. Direct Atomic Scale Observation of the Structure and Chemistry of Order/Disorder Interfaces

    National Research Council Canada - National Science Library

    Srinivasan, R; Banerjee, R; Hwang, J. Y; Viswanathan, G. B; Tiley, J; Fraser, H. L

    2008-01-01

    ... distributed ordered intermetallic precipitates within a disordered matrix. The structure and chemistry at the precipitate/matrix interface plays a critical role in determining the effectiveness of the strengthening mechanism...

  4. Atmospheric chemistry

    Science.gov (United States)

    Andrzej Bytnerowicz; Mark Fenn; Edith B. Allen; Ricardo Cisneros

    2016-01-01

    At present, negative impacts of air pollution on California ecosystems are caused mainly by elevated levels of ozone and nitrogen deposition. Generally, ozone air pollution in California has been improving significantly since the 1970s; however, it still causes serious ecological and human health effects. The most serious ecological effects occur in mixed conifer...

  5. New trends and developments in radiation chemistry

    International Nuclear Information System (INIS)

    1989-10-01

    Radiation chemistry is a branch of chemistry that studies chemical transformations in materials exposed to high-energy radiations. It uses radiation as the initiator of chemical reactions. Practical applications of radiation chemistry today extend to many fields, including health care, food and agriculture, manufacturing, industrial pollution abatement, biotechnology and telecommunications. The important advantage of radiation chemistry lies in its ability to be used to produce, and study, almost any reactive atomic and molecular species playing a part in chemical reactions, synthesis, industrial processes, or in biological systems. The techniques are applicable to gaseous, liquid, solid, and heterogeneous systems. By combining different techniques of radiation chemistry with analytical chemistry, the reaction mechanism and kinetics of chemical reactions are studied. In November 1988 in Bologna, Italy, the IAEA convened an advisory group meeting to assess new trends and developments in radiation chemistry. The present publication includes most of the contributions presented at the meeting. Refs, figs and tabs

  6. Modelled Precipitation Over Greenland

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set includes the annual total precipitation from 1985 to 1999 and monthly total precipitation from January 1985 to December 1999. The data is derived from...

  7. Materials Chemistry

    CERN Document Server

    Fahlman, Bradley D

    2011-01-01

    The 2nd edition of Materials Chemistry builds on the strengths that were recognized by a 2008 Textbook Excellence Award from the Text and Academic Authors Association (TAA). Materials Chemistry addresses inorganic-, organic-, and nano-based materials from a structure vs. property treatment, providing a suitable breadth and depth coverage of the rapidly evolving materials field. The 2nd edition continues to offer innovative coverage and practical perspective throughout. After briefly defining materials chemistry and its history, seven chapters discuss solid-state chemistry, metals, semiconducting materials, organic "soft" materials, nanomaterials, and materials characterization. All chapters have been thoroughly updated and expanded with, for example, new sections on ‘soft lithographic’ patterning, ‘click chemistry’ polymerization, nanotoxicity, graphene, as well as many biomaterials applications. The polymer and ‘soft’ materials chapter represents the largest expansion for the 2nd edition. Each ch...

  8. Green Chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Collison, Melanie

    2011-05-15

    Green chemistry is the science of chemistry used in a way that will not use or create hazardous substances. Dr. Rui Resendes is working in this field at GreenCentre Canada, an offshoot of PARTEQ Innovations in Kingston, Ontario. GreenCentre's preliminary findings suggest their licensed product {sup S}witchable Solutions{sup ,} featuring 3 classes of solvents and a surfactant, may be useful in bitumen oil sands extraction.

  9. Anthropogenic atmospheric precipitation and quality of environment in Ivano-Frankivsk oblast

    OpenAIRE

    Ганжа, Дмитро Дмитрович; Ганжа, Дмитро Дмитрович

    2016-01-01

    It is studied anthropogenic atmospheric precipitation by the content of soluble salts, macroelements and dust in snow water. Total air pollution index was calculated by the measured parameters of precipitation. It was established statistical connections between total pollution index, on the one hand, and the population growth, mortality from tumors and vascular lesions at diseases of the circulatory system, on the other hand

  10. Bioremediation of environmental pollutants

    International Nuclear Information System (INIS)

    Madsen, E.L.

    1992-01-01

    This paper reports on disremediation of environmental pollutants. When a tree falls in the forest, when crop residues are left in the fields, and even when spilled gasoline soaks into the ground, microorganisms go to work. Just as humans eat food to sustain life, microorganisms digest nonliving organic materials, using an astounding diversity of enzymes. In the process of deriving carbon and energy for their own use, microorganisms recycle essential nutrients such as nitrogen and phosphorus to the other species with which they share the biosphere. This has thrown many ecosystems into a unsteady state and has threatened human health. Increasing expertise in analytical chemistry and toxicology has contributed to an understanding of the problems of environmental pollution, and remedies are now being sought. Both physical and chemical processes may be essential to pollution-control technologies, but controlled biodegradation also offers significant promise

  11. General chemistry

    International Nuclear Information System (INIS)

    Kwon, Yeong Sik; Lee, Dong Seop; Ryu, Haung Ryong; Jang, Cheol Hyeon; Choi, Bong Jong; Choi, Sang Won

    1993-07-01

    The book concentrates on the latest general chemistry, which is divided int twenty-three chapters. It deals with basic conception and stoichiometry, nature of gas, structure of atoms, quantum mechanics, symbol and structure of an electron of ion and molecule, chemical thermodynamics, nature of solid, change of state and liquid, properties of solution, chemical equilibrium, solution and acid-base, equilibrium of aqueous solution, electrochemistry, chemical reaction speed, molecule spectroscopy, hydrogen, oxygen and water, metallic atom; 1A, IIA, IIIA, carbon and atom IVA, nonmetal atom and an inert gas, transition metals, lanthanons, and actinoids, nuclear properties and radioactivity, biochemistry and environment chemistry.

  12. Radiation chemistry

    International Nuclear Information System (INIS)

    Swallow, A.J.

    1983-01-01

    The subject is covered in chapters, entitled: introduction (defines scope of article as dealing with the chemistry of reactive species, (e.g. excess electrons, excited states, free radicals and inorganic ions in unusual valency states) as studied using radiation with radiation chemistry in its traditional sense and with biological and industrial applications); gases; water and simple inorganic systems; aqueous metallo-organic compounds and metalloproteins; small organic molecules in aqueous solution; microheterogeneous systems; non-aqueous liquids and solutions; solids; biological macromolecules; synthetic polymers. (U.K.)

  13. Metal transport and remobilisation in a basin affected by acid mine drainage: the role of ochreous amorphous precipitates.

    Science.gov (United States)

    Consani, Sirio; Carbone, Cristina; Dinelli, Enrico; Balić-Žunić, Tonci; Cutroneo, Laura; Capello, Marco; Salviulo, Gabriella; Lucchetti, Gabriella

    2017-06-01

    Metal-polluted mine waters represent a major threat to the quality of waters and sediments in a downstream basin. At the confluence between acidic mine waters and the unpolluted waters of the Gromolo Torrent (Liguria, North-West Italy), the massive formation of an ochreous amorphous precipitate takes place. This precipitate forms a soft blanket that covers the torrent bed and can be observed down to its mouth in the sea. The aim of this work is to evaluate the dispersion of metals in the Gromolo Torrent basin from the abandoned Cu-Fe sulphide mine of Libiola to the Ligurian Sea and to assess the metal remobilisation from the amorphous precipitates. The mineralogy of the superficial sediments collected in the torrent bed and the concentrations of different elements of environmental concern (Cu, Zn, Cd, Co, Cr, Mn, Ni, Pb, As, and Sb) were therefore analysed. The results showed that the precipitates contain high concentration of Fe, Al, Cu, and Zn, significantly modifying the bulk chemistry of the Gromolo Torrent sediments. In order to evaluate the possible remobilisation of ecotoxic elements from the amorphous precipitates, bulk leaching tests were performed with both deionised and seawater. Bulk leaching tests with deionised water mobilised primarily high Pb amounts, but also relatively high concentrations of Fe, Al, Cu, and Zn are released in the leachate. In seawater tests, Fe, Al, Cu, and Zn were released in smaller amounts, while other elements like Mn, Cd, Co, and Ni increased in the released fraction. Pb was still strongly released as in deionised water experiments. The results show that the interaction of precipitates and seawater can remobilise high concentrations of metals, thus affecting the surrounding environment.

  14. The chemistry of plutonium revealed

    International Nuclear Information System (INIS)

    Connick, R.E.

    1990-01-01

    In 1941 one goal of the Manhattan Project was to unravel the chemistry of the synthetic element plutonium as rapidly as possible. Important insights were obtained from tracer experiments, but the full complexity of plutonium chemistry was not revealed until macroscopic amounts (milligrams) became available. Because processes for separation from fission products were aqueous solution based, such solution chemistry was emphasized, particularly precipitation and oxidation-reduction behavior. The latter turned out to be unusually intricate when it was discovered that two more oxidation states existed in aqueous solution than had previously been suspected. Further, it was found that an equilibrium was rapidly established among the four aqueous oxidation states while at the same time any three were not in equilibrium. These and other observations made while doing a crash study of a previously unknown element will be reported

  15. Handbook of heterocyclic chemistry

    National Research Council Canada - National Science Library

    Katritzky, Alan R

    2010-01-01

    ... Heterocyclic Chemistry I (1984) Comprehensive Heterocyclic Chemistry II (1996) Comprehensive Heterocyclic Chemistry III (2008) Comprehensive Organic Functional Group Transformations I (1995) Compreh...

  16. Cerium oxalate precipitation

    International Nuclear Information System (INIS)

    Chang, T.P.

    1987-02-01

    Cerium, a nonradioactive, common stand-in for plutonium in development work, has been used to simulate several plutonium precipitation processes at the Savannah River Laboratory. There are similarities between the plutonium trifluoride and the cerium oxalate precipitations in particle size and extent of plating, but not particle morphology. The equilibrium solubility, precipitation kinetics, particle size, extent of plating, and dissolution characteristics of cerium oxalate have been investigated. Interpretations of particle size and plating based on precipitation kinetics (i.e., nucleation and crystal growth) are presented. 16 refs., 7 figs., 6 tabs

  17. Reinventing Chemistry

    OpenAIRE

    Whitesides, George McClelland

    2015-01-01

    Chemistry is in a period of change, from an era focused on molecules and reactions, to one in which manipulations of systems of molecules and reactions will be essential parts of controlling larger systems. This Essay traces paths from the past to possible futures.

  18. Chemistry Notes

    Science.gov (United States)

    School Science Review, 1972

    1972-01-01

    Short articles on the kinetics of the hydrogen peroxide-iodide ion reaction, simulation of fluidization catalysis, the use of Newman projection diagrams to represent steric relationships in organic chemistry, the use of synthetic substrates for proteolytic enzyme reactions, and two simple clock reactions"--hydrolysis of halogenoalkanes and…

  19. Radiation chemistry and the environment

    International Nuclear Information System (INIS)

    Getoff, F.

    1998-01-01

    The rather strong and many-sided pollution of the environment (atmosphere, water resources, soil) as a consequence of human activities is summarized. The solution of the arised problems by application of radiation chemistry methods and the utilization of modern environmentally ''clean'' and economical technologies, founded on electron beam processing, are mentioned. Some basic environmental problems and their solution are briefly discussed: i) Removal of CO 2 from flue gases and its radiation induced utilization. ii) Principals for degradation of aqueous pollutants by electron beam processing in the presence of ozone (synergistic effect). The radiation chemistry as a modern and manifold discipline with very broad applications can also essentially contribute in the conservation of the environment

  20. Radiation chemistry and the environment

    International Nuclear Information System (INIS)

    Getoff, Nikola

    1999-01-01

    The rather strong and many-sided pollution of the environment (atmosphere, water resources, soil) as a consequence of human activity is summarized. The solution of the arised problems by application of radiation chemistry methods and the utilization of modern environmentally 'clean' and economical technologies, founded on electron beam processing, are mentioned. Some basic environmental problems and their solution are briefly discussed. (i) Removal of CO 2 from flue gases and its radiation induced utilization. (ii) Principals for degradation of aqueous pollutants by electron beam processing in the presence of ozone (synergistic effect). The radiation chemistry as a modern and manifold discipline with very broad applications can also essentially contribute in the conservation of the environment

  1. Atmospheric Chemistry Over Southern Africa

    Science.gov (United States)

    Gatebe, Charles K.; Levy, Robert C.; Thompson, Anne M.

    2011-01-01

    During the southern African dry season, regional haze from mixed industrial pollution, biomass burning aerosol and gases from domestic and grassland fires, and biogenic sources from plants and soils is worsened by a semi-permanent atmosphere gyre over the subcontinent. These factors were a driver of several major international field campaigns in the 1990s and early 2000s, and attracted many scientists to the region. Some researchers were interested in understanding fundamental processes governing chemistry of the atmosphere and interaction with climate change. Others found favorable conditions for evaluating satellite-derived measurements of atmospheric properties and a changing land surface. With that background in mind a workshop on atmospheric chemistry was held in South Africa. Sponsored by the International Commission for Atmospheric Chemistry and Global Pollution (ICACGP; http://www.icacgp.org/), the workshop received generous support from the South African power utility, Eskom, and the Climatology Research Group of the University of the Witwatersrand, Johannesburg, South Africa. The purpose of the workshop was to review some earlier findings as well as more recent findings on southern African climate vulnerability, chemical changes due to urbanization, land-use modification, and how these factors interact. Originally proposed by John Burrows, president of ICACGP, the workshop was the first ICACGP regional workshop to study the interaction of air pollution with global chemical and climate change. Organized locally by the University of the Witwatersrand, the workshop attracted more than 60 delegates from South Africa, Mozambique, Botswana, Zimbabwe, France, Germany, Canada, and the United States. More than 30 presentations were given, exploring both retrospective and prospective aspects of the science. In several talks, attention was focused on southern African chemistry, atmospheric pollution monitoring, and climate processes as they were studied in the field

  2. Water pollution

    OpenAIRE

    Institute, Marine

    2013-01-01

    Students will learn about what causes water pollution and how to be environmentally aware. *Note: Students should understand the concept of the water cycle before moving onto water pollution (see Lesson Plan “Oceans all Around Us”).

  3. Green chemistry applied to corrosion and scale inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Darling, D.; Rakshpal, R. [Environmental Protection Agency, Washington, DC (United States)

    1998-12-31

    Numerous breakthroughs in environmental protection and pollution prevention have been realized in recent years by both industry and academia through the application of green chemistry principles. Green chemistry, or pollution prevention at the molecular level, is chemistry designed to reduce or eliminate the use or generation of hazardous materials associated with the manufacture and application of chemicals. The application of the green chemistry principles to the areas of corrosion and scale inhibitors has resulted in the reduction/elimination of many of the more toxic inhibitors and the development of newer, more environmentally friendly ones.

  4. Water Pollution

    International Nuclear Information System (INIS)

    Goni, J.

    1984-01-01

    This work is about the water pollution. The air and the water interaction cycles is the main idea of the geochemical pollution conception. In the water surface as well as in the deep aquifers we can found cough metals or minerals from the athmosferic air. The activities of mercury fluor and nitrates are important to the pollution study

  5. Air Pollution.

    Science.gov (United States)

    Barker, K.; And Others

    Pollution of the general environment, which exposes an entire population group for an indeterminate period of time, certainly constitutes a problem in public health. Serious aid pollution episodes have resulted in increased mortality and a possible relationship between chronic exposure to a polluted atmosphere and certain diseases has been…

  6. Air Pollution and Environmental Justice Awareness

    Science.gov (United States)

    Bouvier-Brown, N. C.

    2014-12-01

    Air pollution is not equally dispersed in all neighborhoods and this raises many social concerns, such as environmental justice. "Real world" data, whether extracted from online databases or collected in the field, can be used to demonstrate air quality patterns. When students explore these trends, they not only learn about atmospheric chemistry, but they also become socially aware of any inequities. This presentation outlines specific ways to link air pollution and environmental justice suitable for an undergraduate upper division Air Pollution or Atmospheric Chemistry course.

  7. Mass spectrometry. [in organic chemistry

    Science.gov (United States)

    Burlingame, A. L.; Shackleton, C. H. L.; Howe, I.; Chizhov, O. S.

    1978-01-01

    A review of mass spectrometry in organic chemistry is given, dealing with advances in instrumentation and computer techniques, selected topics in gas-phase ion chemistry, and applications in such fields as biomedicine, natural-product studies, and environmental pollution analysis. Innovative techniques and instrumentation are discussed, along with chromatographic-mass spectrometric on-line computer techniques, mass spectral interpretation and management techniques, and such topics in gas-phase ion chemistry as electron-impact ionization and decomposition, photoionization, field ionization and desorption, high-pressure mass spectrometry, ion cyclotron resonance, and isomerization reactions of organic ions. Applications of mass spectrometry are examined with respect to bio-oligomers and their constituents, biomedically important substances, microbiology, environmental organic analysis, and organic geochemistry.

  8. Chemical Composition of Water Soluble Inorganic Species in Precipitation at Shihwa Basin, Korea

    Directory of Open Access Journals (Sweden)

    Seung-Myung Park

    2015-05-01

    Full Text Available Weekly rain samples were collected in coastal areas of the Shihwa Basin (Korea from June 2000 to November 2007. The study region includes industrial, rural, and agricultural areas. Wet precipitation was analyzed for conductivity, pH, Cl−, NO3−, SO42−, Na+, K+, Mg2+, NH4+, and Ca2+. The major components of precipitation in the Shihwa Basin were NH4+, volume-weighted mean (VWM of 44.6 µeq∙L−1, representing 43% of all cations, and SO42−, with the highest concentration among the anions (55% at all stations. The pH ranged from 3.4 to 7.7 with a VMM of 4.84. H+ was weakly but positively correlated with SO42− (r = 0.39, p < 0.001 and NO3− (r = 0.38, p < 0.001. About 66% of the acidity was neutralized by NH4+ and Ca2+. The Cl−/Na+ ratio of the precipitation was 37% higher than seawater Cl−/Na+. The high SO42−/NO3− ratio of 2.3 is attributed to the influence of the surrounding industrial sources. Results from positive matrix factorization showed that the precipitation chemistry in Shihwa Basin was influenced by secondary nitrate and sulfate (41% ± 1.1%, followed by sea salt and Asian dust, contributing 23% ± 3.9% and 17% ± 0.2%, respectively. In this study, the annual trends of SO42− and NO3− (p < 0.05 increased, different from the trends in some locations, due to the influence of the expanding power generating facilities located in the upwind area. The increasing trends of SO42− and NO3− in the study region have important implications for reducing air pollution in accordance with national energy policy.

  9. PRECIPITATION OF PROTACTINIUM

    Science.gov (United States)

    Moore, R.L.

    1958-07-15

    An lmprovement in the separation of protactinium from aqueous nitric acid solutions is described. 1t covers the use of lead dioxide and tin dioxide as carrier precipitates for the protactinium. In carrying out the process, divalent lead or divalent tin is addcd to the solution and oxidized, causing formation of a carrier precipitate of lead dioxide or stannic oxide, respectively.

  10. Global Precipitation Measurement Poster

    Science.gov (United States)

    Azarbarzin, Art

    2010-01-01

    This poster presents an overview of the Global Precipitation Measurement (GPM) constellation of satellites which are designed to measure the Earth's precipitation. It includes the schedule of launches for the various satellites in the constellation, and the coverage of the constellation, It also reviews the mission capabilities, and the mission science objectives.

  11. Polluted Runoff: Nonpoint Source Pollution

    Science.gov (United States)

    Nonpoint Source (NPS) pollution is caused by rainfall or snowmelt moving over and through the ground, it picks up and carries natural and human-made pollutants, depositing them into lakes, rivers, wetlands, coastal waters and ground waters.

  12. Streamwater chemistry and nutrient budgets for forested watersheds in New England: variability and management implications

    Science.gov (United States)

    J.W. Hornbeck; S.W. Bailey; D.C. Buso; J.B. Shanley

    1997-01-01

    Chemistry of precipitation and streamwater and resulting input-output budgets for nutrient ions were determined concurrently for three years on three upland, forested watersheds located within an 80 km radius in central New England. Chemistry of precipitation and inputs of nutrients via wet deposition were similar among the three watersheds and were generally typical...

  13. Air pollution

    Energy Technology Data Exchange (ETDEWEB)

    Strauss, W; Mainwaring, S J

    1984-01-01

    This book deals with the nature of air pollution. The numerous sources of unwanted gases and dust particles in the air are discussed. Details are presented of the effects of pollutants on man, animals, vegetation and on inanimate materials. Methods used to measure, monitor and control air pollution are presented. The authors include information on the socio-economic factors which impinge on pollution control and on the problems the future will bring as methods of generating energy change and industries provide new sources of pollutants.

  14. Oil pollution

    International Nuclear Information System (INIS)

    Mankabady, Samir.

    1994-08-01

    Oil enters the marine environment when it is discharged, or has escaped, during transport, drilling, shipping, accidents, dumping and offshore operations. This book serves as a reference both on the various complex international operational and legal matters of oil pollution using examples such as the Exxon Valdez, the Braer and Lord Donaldson's report. The chapters include the development of international rules on the marine environment, the prevention of marine pollution from shipping activities, liability for oil pollution damage, the conflict of the 1990 Oil Pollution Act and the 1992 protocols and finally the cooperation and response to pollution incidents. (UK)

  15. Chemistry and physics

    International Nuclear Information System (INIS)

    Broerse, J.J.; Barendsen, G.W.; Kal, H.B.; Kogel, A.J. van der

    1983-01-01

    This book contains the extended abstracts of the contributions of the poster workshop sessions on chemistry and physics of the 7th international congress of radiation research. They cover the following main topics: primary processes in radiation physics and chemistry, general chemistry in radiation chemistry, DNA and model systems in radiation chemistry, molecules of biological interest in radiation chemistry, techniques in radiation chemistry, hot atom chemistry. refs.; figs.; tabs

  16. Fine chemistry

    International Nuclear Information System (INIS)

    Laszlo, P.

    1988-01-01

    The 1988 progress report of the Fine Chemistry laboratory (Polytechnic School, France) is presented. The research programs are centered on the renewal of the organic chemistry most important reactions and on the invention of new, highly efficient and highly selective reactions, by applying low cost reagents and solvents. An important research domain concerns the study and fabrication of new catalysts. They are obtained by means of the reactive sputtering of the metals and metal oxydes thin films. The Monte Carlo simulations of the long-range electrostatic interaction in a clay and the obtention of acrylamides from anhydrous or acrylic ester are summarized. Moreover, the results obtained in the field of catalysis are also given. The published papers and the congress communications are included [fr

  17. Radioanalytical chemistry

    International Nuclear Information System (INIS)

    1982-01-01

    The bibliography of Hungarian literature in the field of radioanalytical chemistry covers the four-year period 1976-1979. The list of papers contains 290 references in the alphabetical order of the first authors. The majority of the titles belongs to neutron activation analysis, labelling, separation and determination of radioactive isotopes. Other important fields like radioimmunoassay, environmental protection etc. are covered as well. (Sz.J.)

  18. Analytical chemistry

    International Nuclear Information System (INIS)

    Anon.

    1985-01-01

    The division for Analytical Chemistry continued to try and develope an accurate method for the separation of trace amounts from mixtures which, contain various other elements. Ion exchange chromatography is of special importance in this regard. New separation techniques were tried on certain trace amounts in South African standard rock materials and special ceramics. Methods were also tested for the separation of carrier-free radioisotopes from irradiated cyclotron discs

  19. Industrial chemistry engineering

    International Nuclear Information System (INIS)

    1993-01-01

    This book on industrial chemistry engineering is divided in two parts. The first part deals with industrial chemistry, inorganic industrial chemistry, organic industrial chemistry, analytical chemistry and practical questions. The last parts explain the chemical industry, a unit parts and thermodynamics in chemical industry and reference. It reveals the test subjects for the industrial chemistry engineering with a written examination and practical skill.

  20. Computational chemistry

    Science.gov (United States)

    Arnold, J. O.

    1987-01-01

    With the advent of supercomputers, modern computational chemistry algorithms and codes, a powerful tool was created to help fill NASA's continuing need for information on the properties of matter in hostile or unusual environments. Computational resources provided under the National Aerodynamics Simulator (NAS) program were a cornerstone for recent advancements in this field. Properties of gases, materials, and their interactions can be determined from solutions of the governing equations. In the case of gases, for example, radiative transition probabilites per particle, bond-dissociation energies, and rates of simple chemical reactions can be determined computationally as reliably as from experiment. The data are proving to be quite valuable in providing inputs to real-gas flow simulation codes used to compute aerothermodynamic loads on NASA's aeroassist orbital transfer vehicles and a host of problems related to the National Aerospace Plane Program. Although more approximate, similar solutions can be obtained for ensembles of atoms simulating small particles of materials with and without the presence of gases. Computational chemistry has application in studying catalysis, properties of polymers, all of interest to various NASA missions, including those previously mentioned. In addition to discussing these applications of computational chemistry within NASA, the governing equations and the need for supercomputers for their solution is outlined.

  1. Frontiers in Atmospheric Chemistry Modelling

    Science.gov (United States)

    Colette, Augustin; Bessagnet, Bertrand; Meleux, Frederik; Rouïl, Laurence

    2013-04-01

    The first pan-European kilometre-scale atmospheric chemistry simulation is introduced. The continental-scale air pollution episode of January 2009 is modelled with the CHIMERE offline chemistry-transport model with a massive grid of 2 million horizontal points, performed on 2000 CPU of a high performance computing system hosted by the Research and Technology Computing Center at the French Alternative Energies and Atomic Energy Commission (CCRT/CEA). Besides the technical challenge, which demonstrated the robustness of the selected air quality model, we discuss the added value in terms of air pollution modelling and decision support. The comparison with in-situ observations shows that model biases are significantly improved despite some spurious added spatial variability attributed to shortcomings in the emission downscaling process and coarse resolution of the meteorological fields. The increased spatial resolution is clearly beneficial for the detection of exceedances and exposure modelling. We reveal small scale air pollution patterns that highlight the contribution of city plumes to background air pollution levels. Up to a factor 5 underestimation of the fraction of population exposed to detrimental levels of pollution can be obtained with a coarse simulation if subgrid scale correction such as urban increments are ignored. This experiment opens new perspectives for environmental decision making. After two decades of efforts to reduce air pollutant emissions across Europe, the challenge is now to find the optimal trade-off between national and local air quality management strategies. While the first approach is based on sectoral strategies and energy policies, the later builds upon new alternatives such as urban development. The strategies, the decision pathways and the involvement of individual citizen differ, and a compromise based on cost and efficiency must be found. We illustrated how high performance computing in atmospheric science can contribute to this

  2. Seasonal variations of dissolved organic carbon in precipitation over urban and forest sites in central Poland.

    Science.gov (United States)

    Siudek, Patrycja; Frankowski, Marcin; Siepak, Jerzy

    2015-07-01

    Spatial and temporal variability of carbon species in rainwater (bulk deposition) was studied for the first time at two sites located in urban area of Poznań City and protected woodland area (Jeziory), in central Poland, between April and December 2013. The mean concentration of total carbon (TC) for the first site was 5.86 mg L(-1), whereas for the second, 5.21 mg L(-1). Dissolved organic carbon (DOC) concentration accounted for, on average, 87 and 91 % of total carbon in precipitation at urban and non-urban sites, respectively. Significant changes in TC concentrations in rainwater were observed at both sites, indicating that atmospheric transformation, transport, and removal mechanisms of carbonaceous particles were affected by seasonal fluctuations in biogenic/anthropogenic emission and meteorological conditions (i.e., precipitation height and type, atmospheric transport). During the warm season, the DOC concentration in rainwater was mostly influenced by mixed natural and anthropogenic sources. In contrast, during the cold season, the DOC concentration significantly increased mainly as a result of anthropogenic activities, i.e., intensive coal combustion, domestic wood burning, high-temperature processes, etc. In addition, during the winter measurements, significant differences in mean DOC concentration (Kruskal-Wallis test, p urban and non-urban sites. These data imply that carbonaceous compounds are of crucial importance in atmospheric chemistry and should be considered as an important parameter while considering wet deposition, reactions with different substances, especially over polluted environments.

  3. Atmospheric pollution

    International Nuclear Information System (INIS)

    Lambrozo, J.; Guillossou, G.

    2008-01-01

    The atmosphere is the reservoir of numerous pollutants (nitrogen oxides, sulfur oxides, carbon oxides, particulates, volatile organic compounds, polycyclic aromatic hydrocarbons) from natural origin or anthropogenic origin ( industry, transport, agriculture, district heating). With epidemiologic studies the atmospheric pollution is associated with an increase of respiratory and cardiovascular diseases. At the european level, the technological progress, the legislation have allowed a reduction of pollutant emissions, however these efforts have to be continued because the sanitary impact of atmospheric pollution must not be underestimated, even if the risks appear less important that these ones in relation with tobacco, inside pollution or others factors of cardiovascular risks. Indeed, on these last factors an individual action is possible for the exposure to air pollution people have no control. (N.C.)

  4. Industrial ecology: Environmental chemistry and hazardous waste

    Energy Technology Data Exchange (ETDEWEB)

    Manahan, S.E. [Univ. of Missouri, Columbia, MO (United States). Dept. of Chemistry

    1999-01-01

    Industrial ecology may be a relatively new concept -- yet it`s already proven instrumental for solving a wide variety of problems involving pollution and hazardous waste, especially where available material resources have been limited. By treating industrial systems in a manner that parallels ecological systems in nature, industrial ecology provides a substantial addition to the technologies of environmental chemistry. Stanley E. Manahan, bestselling author of many environmental chemistry books for Lewis Publishers, now examines Industrial Ecology: Environmental Chemistry and Hazardous Waste. His study of this innovative technology uses an overall framework of industrial ecology to cover hazardous wastes from an environmental chemistry perspective. Chapters one to seven focus on how industrial ecology relates to environmental science and technology, with consideration of the anthrosphere as one of five major environmental spheres. Subsequent chapters deal specifically with hazardous substances and hazardous waste, as they relate to industrial ecology and environmental chemistry.

  5. Theoretical chemistry periodicities in chemistry and biology

    CERN Document Server

    Eyring, Henry

    1978-01-01

    Theoretical Chemistry: Periodicities in Chemistry and Biology, Volume 4 covers the aspects of theoretical chemistry. The book discusses the stably rotating patterns of reaction and diffusion; the chemistry of inorganic systems exhibiting nonmonotonic behavior; and population cycles. The text also describes the mathematical modeling of excitable media in neurobiology and chemistry; oscillating enzyme reactions; and oscillatory properties and excitability of the heart cell membrane. Selected topics from the theory of physico-chemical instabilities are also encompassed. Chemists, mechanical engin

  6. Precipitates in irradiated Zircaloy

    International Nuclear Information System (INIS)

    Chung, H.M.

    1985-10-01

    Precipitates in high-burnup (>20 MWd/kg U) Zircaloy spent-fuel cladding discharged from commercial boiling- and pressurized-water reactors have been characterized by TEM-HVEM. Three classes of primary precipitates were observed in the irradiated Zircaloys: Zr 3 O (2 to 6 nm), cubic-ZrO 2 (greater than or equal to 10 nm), and delta-hydride (35 to 100 nm). The former two precipitations appears to be irradiation induced in nature. Zr(Fe/sub x/Cr/sub 1-x/) 2 and Zr 2 (Fe/sub x/Ni/sub 1-x/) intermetallics, which are the primary precipitates in unirradiated Zircaloys, were largely dissolved after the high burnup. It seems, therefore, that the influence of the size and distribution of the intermetallics on the corrosion behavior may be quite different for the irradiated Zircaloys

  7. WPA Precipitation Tabulations

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Hourly precipitation data tabulated under the Work Projects Administration (WPA), a New Deal program created to reduce unemployment during the Great Depression....

  8. Environmental pollution

    International Nuclear Information System (INIS)

    Odzuck, W.

    1982-01-01

    The volume of the anthropogenic pollution of the environment (incl. radioactivity) is of great economical importance and has also a meaning to the health and happiness of people. The pocket book introduces into the whole problem by giving exact information and data. After a general survey, the pollutions of urban-industrial, and aquatic ecosystems are dealt with. The book closes with indications as to general principles, specific dangers, and the fature development of the environmental pollution. (orig.) [de

  9. Air pollution

    OpenAIRE

    MacKenbach, JP; Henschel, S; Goodman, P; McKee, M

    2013-01-01

    The human costs of air pollution are considerable in Jordan. According to a report published in 2000 by the World Bank under the Mediterranean Environmental Technical Assistance Program (METAP), approximately 600 people die prematurely each year in Jordan because of urban pollution. 50-90% of air pollution in Jordanian towns is caused by road traffic. Readings taken in 2007 by Jordanian researchers showed that levels of black carbon particles in the air were higher in urban areas (caused by v...

  10. Solution chemistry

    Energy Technology Data Exchange (ETDEWEB)

    None

    1973-07-01

    Research progress is reported on studies in heavy element chemistry. Topics considered are: synergistic complexes of plutonyl ion; water uptake in synergistic systems; formation constants of some uranyl BETA -diketone complexes; thermodynamic acid dissociation constants of BETA -diketones; thermodynamic formation constants of uranyl BETA -diketonates; thiocyanate complexes of some trivalent lanthanides and actinides; stability constants of actinide complexes using dinonyl naphthalenesulfonic acid extraction; TBP extraction of actinides; stability constants of complexes of Pu(III) with 5- sulfosalicycllc acid; and solvent extraction behavior of Pu( VII). (DHM)

  11. Interstellar chemistry.

    Science.gov (United States)

    Klemperer, William

    2006-08-15

    In the past half century, radioastronomy has changed our perception and understanding of the universe. In this issue of PNAS, the molecular chemistry directly observed within the galaxy is discussed. For the most part, the description of the molecular transformations requires specific kinetic schemes rather than chemical thermodynamics. Ionization of the very abundant molecular hydrogen and atomic helium followed by their secondary reactions is discussed. The rich variety of organic species observed is a challenge for complete understanding. The role and nature of reactions involving grain surfaces as well as new spectroscopic observations of interstellar and circumstellar regions are topics presented in this special feature.

  12. General chemistry

    International Nuclear Information System (INIS)

    2009-01-01

    This book explains chemical equilibrium with nature and characteristic of chemical equilibrium, law of mass action and direction of chemical equilibrium, acid-base equilibrium with principle of acid and base and amino acid, solubility and precipitation equilibrium with equilibrium of solubility, complex ion and solubility, electrochemistry on oxidation-reduction reaction, battery and fuel cell, decay and electrolysis, chemical reaction speed and nuclear reaction with Michaelis-Menten mechanism safety of nuclear, transition elements and coordination compound with introduction, name, structure and ligand EDTA and solid structure with categorization of solid and unit cell.

  13. Comparison between POES energetic electron precipitation observations and riometer absorptions: Implications for determining true precipitation fluxes

    Science.gov (United States)

    Rodger, Craig J.; Kavanagh, Andrew J.; Clilverd, Mark A.; Marple, Steve R.

    2013-12-01

    electron precipitation (EEP) impacts the chemistry of the middle atmosphere with growing evidence of coupling to surface temperatures at high latitudes. To better understand this link, it is essential to have realistic observations to properly characterize precipitation and which can be incorporated into chemistry-climate models. The Polar-orbiting Operational Environmental Satellite (POES) detectors measure precipitating particles but only integral fluxes and only in a fraction of the bounce loss cone. Ground-based riometers respond to precipitation from the whole bounce loss cone; they measure the cosmic radio noise absorption (CNA), a qualitative proxy with scant direct information on the energy flux of EEP. POES observations should have a direct relationship with ΔCNA and comparing the two will clarify their utility in studies of atmospheric change. We determined ionospheric changes produced by the EEP measured by the POES spacecraft in ~250 overpasses of an imaging riometer in northern Finland. The ΔCNA modeled from the POES data is 10-15 times less than the observed ΔCNA when the >30 keV flux is reported as ground-based measurements. The discrepancy occurs mostly during periods of low geomagnetic activity, and we contend that weak diffusion is dominating the pitch angle scattering into the bounce loss cone at these times. A correction to the calculation using measurements of the trapped flux considerably reduces the discrepancy and provides further support to our hypothesis that weak diffusion leads to underestimates of the EEP.

  14. Interactions of Climate Change, Air Pollution, and Human Health.

    Science.gov (United States)

    Kinney, Patrick L

    2018-03-01

    I review literature on the impacts of climate change on air quality and human health, with a focus on articles published from 2013 on ozone and airborne particles. Selected previous literature is discussed where relevant in tracing the origins of our current knowledge. Climate and weather have strong influences on the spatial and temporal distribution of air pollution concentrations. Emissions of ozone and PM 2.5 precursors increase at higher ambient temperatures. The reactions that form ozone occur faster with greater sunlight and higher temperatures. Weather systems influence the movement and dispersion of air pollutants in the atmosphere through the action of winds, vertical mixing, and precipitation, all of which are likely to alter in a changing climate. Recent studies indicate that, holding anthropogenic air pollution emissions constant, ozone concentrations in populated regions will tend to increase in future climate scenarios. For the USA, the climate impact on ozone is most consistently seen in north-central and north-eastern states, with the potential for many thousands of additional ozone-related deaths. The sensitivity of anthropogenic PM 2.5 to climate is more variable across studies and regions, owing to the varied nature of PM constituents, as well as to less complete characterization of PM reaction chemistry in available atmospheric models. However, PM emitted by wildland fires is likely to become an increasing health risk in many parts of the world as climate continues to change. The complex interactions between climate change and air quality imply that future policies to mitigate these twin challenges will benefit from greater coordination. Assessing the health implications of alternative policy approaches towards climate and pollution mitigation will be a critical area of future work.

  15. Problem of air pollution

    Energy Technology Data Exchange (ETDEWEB)

    Berge, H

    1964-01-01

    The effects of air pollutants on plants are dependent on and modified by climatic, orographic, edaphic, and biotic factors; the synergism of pollutants; and differences in the sensitivity of individual plants and species. Sulfur dioxide and fluorine are the most dangerous pollutants for plants, but ammonia, hydrogen sulfide, nitrogen oxides, nitric acid, chlorine, hydrochloric acid, bromine, iodine, hydrocyanic acid, ethylene, carbon monoxide, hydrocarbons, mercaptans, asphalt and tar vapors, mercury, and selenium can also inflict damage. Young leaves, sensitive to H/sub 2/S, nitrogen oxides, Cl, HCl, HCN, mercaptans, Hg, and sulfuric acid, are more resistant to SO/sub 2/, gaseous F compounds, ethylene, and selenium than older leaves. Damage is most serious when pollutants enter leaves simultaneously or alternately through epidermis and stomata. The yellow-to-brown coloration of leaves is usually a result of the precipitation of tanning. Plasmolysis is caused by SO/sub 2/, gaseous F compounds, ammonia, nitrogen oxides, HNO/sub 3/, Br, asphalt and tar vapors, while photosynthesis is stimulated by traces of ammonia, HNO/sub 3/, and saturated hydrocarbons. Increased transpiration due to SO/sub 2/ and HCl and elevated permeability and osmosis due to SO/sub 2/ were observed. 9 references, 12 figures, 1 table.

  16. Misconceptions of Concepts in Chemistry among Senior Secondary ...

    African Journals Online (AJOL)

    This study examined the misconceptions by chemistry teachers of senior secondary three (SSIII) in Cross River State, Nigeria. Concepts investigated were hydrocarbons, alkanols, alkanoic acids, pollution, classification and nomenclature of carbon compounds, natural products, chemistry in industry, extraction of metals, fats ...

  17. Role of analytical chemistry in environment and health

    International Nuclear Information System (INIS)

    Kushwaha, H.S.; Puranik, V.D.; Tripathi, R.M.

    2007-01-01

    Analytical chemistry plays an important role in the protection of human health from biological, chemical and radiological hazards in the environment. It is highly useful in the areas of environmental health sciences, such as air pollution, environmental chemistry, environmental management; environmental toxicology, industrial hygiene, and water quality

  18. Radiation chemistry and bioradical chemistry

    International Nuclear Information System (INIS)

    Ferradini, C.

    1991-01-01

    Oxygen metabolism results, at the cellular level, in the formation of superoxyde radical O 2 - · and probably also of hydroxyl radical OH·. Other radical species can be produced from exogenous or endogenous molecules and nearly all of them have the possibility to react with oxygen giving peroxyradicals. Some of these transients play a role in various biological processes such as phagocytosis, inflammation or ischemy although the mechanisms invoked are poorly understood. Radiation chemistry is an invaluable tool for obtaining a quantitative view of these mechanisms. A description is given of this interaction [fr

  19. Air pollution

    International Nuclear Information System (INIS)

    Anon.

    2008-01-01

    Air pollution has accompanied and developed with the industrial age, since its beginnings. This very complete review furnishes the toxicological data available for the principal pollutants and assesses the epidemiologic studies thus far conducted. It also describes European regulations and international commitments for the reduction of emissions. (author)

  20. Acidic precipitation, Vol. 1: Case studies. Advances in environmental science

    Energy Technology Data Exchange (ETDEWEB)

    Adriano, D.C.; Havas, M. (eds.)

    1989-01-01

    As has been the case with many environmental issues of the twentieth century, acidic precipitation has its origin in emissions to the atmosphere of numerous compounds from both natural and man-made sources. This volume of the subseries Acidic precipitation emphasizes some of the classical interactions between acidic deposition and ecological effects. It covers the cycling, behavior, and effects of acidic components in nature. Included are the effects of acidic deposition on soil chemistry, soil solution chemistry, aquatic chemistry, forest productivity, and fish populations. Several major ecological consequences, such as a decline in forest productivity, soil and water acidification, depletion of fish populations, and slower litter decomposition are highlighted. A chapter is devoted to the comparative biogeochemistry of aluminum, encompassing several ecosystems in North America and Europe. Nine chapters have been processed separately for inclusion in the appropriate data bases.

  1. Fundamentals of nuclear chemistry

    International Nuclear Information System (INIS)

    Majer, K.

    1982-01-01

    The textbook is a Czech-to-German translation of the second revised edition and covers the subject under the headings: general nuclear chemistry, methods of nuclear chemistry, preparative nuclear chemistry, analytical nuclear chemistry, and applied chemistry. The book is especially directed to students

  2. Modelling water fluxes for the analysis of diffuse pollution at the river basin scale

    NARCIS (Netherlands)

    Wit, de M.; Meinardi, C.R.; Wendland, F.; Kunkel, R.

    2000-01-01

    Diffuse pollution is a significant and sometimes even major component of surface water pollution. Diffuse inputs of pollutants to the surface water are related to runoff of precipitation. This means that the analysis of diffuse pollutant fluxes from the land surface to the surface water requires an

  3. Cyclodextrin chemistry

    International Nuclear Information System (INIS)

    Khan, M.Z.; Chuaqui, C.A.

    1990-05-01

    The chemistry of cyclodextrins was studied. This study included synthesising some cyclodextrin derivatives, preparing selected inclusion complexes with cyclodextrin and investigating the effects of gamma irradiation on cyclodextrins and certain linear oligosaccharides. This report presents a brief review of the structure and properties of cyclodextrins, the synthesis of cyclodextrin derivatives, their complexation and applications. This is followed by a description of the synthesis of some cyclodextrin derivatives and the preparation of inclusion complexes of cyclodextrin with some organic compounds. Finally, the effects of gamma irradiation on cyclodextrins, some of their derivatives and certain structurally related carbohydrates are discussed. The gamma irradiation studies were carried out for two reasons: to study the effects of gamma irradiation on cyclodextrins and their derivatives; and to investigate selectivity during the gamma irradiation of cyclodextrin derivatives

  4. Astronomical chemistry.

    Science.gov (United States)

    Klemperer, William

    2011-01-01

    The discovery of polar polyatomic molecules in higher-density regions of the interstellar medium by means of their rotational emission detected by radioastronomy has changed our conception of the universe from essentially atomic to highly molecular. We discuss models for molecule formation, emphasizing the general lack of thermodynamic equilibrium. Detailed chemical kinetics is needed to understand molecule formation as well as destruction. Ion molecule reactions appear to be an important class for the generally low temperatures of the interstellar medium. The need for the intrinsically high-quality factor of rotational transitions to definitively pin down molecular emitters has been well established by radioastronomy. The observation of abundant molecular ions both positive and, as recently observed, negative provides benchmarks for chemical kinetic schemes. Of considerable importance in guiding our understanding of astronomical chemistry is the fact that the larger molecules (with more than five atoms) are all organic.

  5. Reburning chemistry

    International Nuclear Information System (INIS)

    Kilpin, P.; Hupa, M.; Glarborg, P.

    1992-01-01

    No reduction chemistry in natural gas (methane) reburning was studied using detailed kinetic modeling. A reaction set including 225 reversible elementary gas-phase reactions and 48 chemical species was applied to an ideal plug flow reactor, and the most important reactions leading to NO reduction were identified and quantified for a number of conditions relevant for natural gas reburning. In addition, the influence of different process parameters on the NO reduction was investigated in the reburn zone and burn-out zone, respectively. Further, comparison of the calculations to available laboratory-scale data on reburning is made. In this paper, the impact of various fluid dynamic, mixing, and chemical effects---not accounted for in the calculations---on the NO reduction and the optimum reburning conditions predicted is discussed

  6. Combustion chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Brown, N.J. [Lawrence Berkeley Laboratory, CA (United States)

    1993-12-01

    This research is concerned with the development and use of sensitivity analysis tools to probe the response of dependent variables to model input variables. Sensitivity analysis is important at all levels of combustion modeling. This group`s research continues to be focused on elucidating the interrelationship between features in the underlying potential energy surface (obtained from ab initio quantum chemistry calculations) and their responses in the quantum dynamics, e.g., reactive transition probabilities, cross sections, and thermal rate coefficients. The goals of this research are: (i) to provide feedback information to quantum chemists in their potential surface refinement efforts, and (ii) to gain a better understanding of how various regions in the potential influence the dynamics. These investigations are carried out with the methodology of quantum functional sensitivity analysis (QFSA).

  7. Thermal behaviour of natural and synthetic iron precipitates from mine drainage

    Czech Academy of Sciences Publication Activity Database

    Pulišová, Petra; Máša, B.; Michalková, E.; Večerníková, Eva; Maříková, Monika; Bezdička, Petr; Murafa, Nataliya; Šubrt, Jan

    2014-01-01

    Roč. 116, č. 2 (2014), s. 625-632 ISSN 1388-6150 R&D Projects: GA MŠk 7AMB12SK155 Institutional support: RVO:61388980 Keywords : Thermogravimetry * Differential thermal analysis * X-ray diffraction analysis * Acid mine drainage * Iron precipitates * Precipitation with urea Subject RIV: CA - Inorganic Chemistry Impact factor: 2.042, year: 2014

  8. Enhancement of regional wet deposition estimates based on modeled precipitation inputs

    Science.gov (United States)

    James A. Lynch; Jeffery W. Grimm; Edward S. Corbett

    1996-01-01

    Application of a variety of two-dimensional interpolation algorithms to precipitation chemistry data gathered at scattered monitoring sites for the purpose of estimating precipitation- born ionic inputs for specific points or regions have failed to produce accurate estimates. The accuracy of these estimates is particularly poor in areas of high topographic relief....

  9. Centrifugal precipitation chromatography

    Science.gov (United States)

    Ito, Yoichiro; Lin, Qi

    2009-01-01

    Centrifugal precipitation chromatography separates analytes according their solubility in ammonium sulfate (AS) solution and other precipitants. The separation column is made from a pair of long spiral channels partitioned with a semipermeable membrane. In a typical separation, concentrated ammonium sulfate is eluted through one channel while water is eluted through the other channel in the opposite direction. The countercurrent process forms an exponential AS concentration gradient through the water channel. Consequently, protein samples injected into the water channel is subjected to a steadily increasing AS concentration and at the critical AS concentration they are precipitated and deposited in the channel bed by the centrifugal force. Then the chromatographic separation is started by gradually reducing the AS concentration in the AS channel which lowers the AS gradient concentration in the water channel. This results in dissolution of deposited proteins which are again precipitated at an advanced critical point as they move through the channel. Consequently, proteins repeat precipitation and dissolution through a long channel and finally eluted out from the column in the order of their solubility in the AS solution. The present method has been successfully applied to a number of analytes including human serum proteins, recombinant ketosteroid isomerase, carotenoid cleavage enzymes, plasmid DNA, polysaccharide, polymerized pigments, PEG-protein conjugates, etc. The method is capable to single out the target species of proteins by affinity ligand or immunoaffinity separation. PMID:19541553

  10. Acid precipitation in Europe and Asia

    International Nuclear Information System (INIS)

    Angell, Valter

    2000-01-01

    The article surveys acid precipitation problems in the region, discusses the sources, the pollutant composition and distribution, the work with the RAINS models as well as the organisation of and the results of joint incentives in the region. The acidification problems in China and some of the Norwegian participation efforts are reviewed. The author points out that much of the acidic precipitation and the environmental problems in Eurasia are due to the use of coal rich in sulphur, that the energy and environmental policies differs throughout the region because of differences in ecology and development levels and that Asia is far more heterogeneous than Europe as to the conditions for co-ordinated efforts against acid precipitation. The differences in economy, geopolitical situation, environmental policies etc. are larger than in Europe and a considerable international effort will be required in order to succeed. Should the regional model RAINS-Asia be used as basis for further co-ordinated efforts on acid precipitation thorough evaluations on costs and advantages are needed. The conditions and need for modelling as basis for international agreements between Asiatic countries are not the same as in Europe. Finally international development organisations have and will continue to play an important part in the work for reducing acid precipitation in Asia. The Asiatic countries may also greatly benefit in the battle against acid precipitation from the experiences of the industrialised countries. However, Asiatic countries will have to meet the major costs of emission reduction themselves. The main question is what emphasis will be put on the long term environmental profits and on the need for rapid economic growth of materially impoverished people. Other development directions than those used by the industrialised countries, seems to be needed

  11. Why Teach Environmental Chemistry?

    Science.gov (United States)

    Gardner, Marjorie H.

    1974-01-01

    Discusses the importance of teaching environmental chemistry in secondary school science classes, and outlines five examples of environmental chemistry problems that focus on major concepts of chemistry and have critical implications for human survival and well-being. (JR)

  12. Combustion chemistry. Activities in the CHEC research programme

    Energy Technology Data Exchange (ETDEWEB)

    Dam-Johansen, K; Johnsson, J E; Glarborg, P; Frandsen, F; Jensen, A; Oestberg, M [Technical Univ. of Denmark, Dept. of Chemical Engineering, Lyngby (Denmark)

    1996-12-01

    The combustion chemistry in the oxidation of fossil fuels and biofuels determines together with mixing and heat transfer the required size of a furnace, the emission of gaseous pollutants, and the formation of ash and deposits on surfaces. This paper describes technologies for solid fuels combustion and gives a summary of the fuels, the pollutant chemistry and the inorganic chemistry in combustion processes. Emphasis is put on the work carried out in the CHEC (Combustion and Harmful Emission Control Research Programme). (au) 173 refs.

  13. Precipitation washout (a bibliography with abstracts). Period covered: 1964--June 1975

    International Nuclear Information System (INIS)

    Lehmann, E.J.

    1975-06-01

    The reports cited in this bibliography cover the removal of pollutants, radioactive isotopes, and dust by rain and snow. The theory, modeling, sampling, and effects of precipitation washout are presented. (auth)

  14. Precipitation washout (a bibliography with abstracts). Report for 1964-July 1978. 126 Abstracts

    International Nuclear Information System (INIS)

    Brown, R.J.

    1978-07-01

    The reports cited in the bibliography cover the removal of pollutants, radioactive isotopes, and dust by rain and snow. The theory, modelling, sampling, and effects of precipitation washout are presented

  15. Environmental chemistry. Seventh edition

    Energy Technology Data Exchange (ETDEWEB)

    Manahan, S.E. [Univ. of Missouri, Columbia, MO (United States)

    1999-11-01

    This book presents a basic understanding of environmental chemistry and its applications. In addition to providing updated materials in this field, the book emphasizes the major concepts essential to the practice of environmental chemistry. Topics of discussion include the following: toxicological chemistry; toxicological chemistry of chemical substances; chemical analysis of water and wastewater; chemical analysis of wastes and solids; air and gas analysis; chemical analysis of biological materials and xenobiotics; fundamentals of chemistry; and fundamentals of organic chemistry.

  16. Environmental Pollution

    International Nuclear Information System (INIS)

    Won, Jong IK

    1990-03-01

    This book tells US that what nature is, which gives descriptions of the world of living things like the role of plant, order of the vegetable kingdom, the world of plant, destruction of the natural world, and the world of bugs, nature and human with man's survive and change of nature, environment and human, and in creasing population and environment, philosophy of conservation of nature on meaning, destroy and management, and direction, air pollution spot, water pollution, soil pollution conservation of nature and industry case of foreign country and view of environment and environmental assimilating capacity.

  17. THE STUDIES OF METAL CONTENT IN PRECIPITATION WATER IN LUBELSKIE AND LUBUSKIE VOIVODESHIPS IN 2013

    Directory of Open Access Journals (Sweden)

    Agnieszka Malec

    2015-09-01

    Full Text Available This paper presents the results of the studies of metal content in precipitation water in 2013, recorded at measuring points within Lubelskie and Lubuskie Voivodeships. It provides a detailed description of the method of collecting and analysing water samples in respect of light- and heavy-metal determination. Based on the results, a general assessment was made of the condition of the environment in the areas in question. Also, the sources of pollution in wet precipitation, and the effects of their introduction into the environment, were determined. It was found that the main pollution elements of precipitation water were linked to anthropogenic sources. The study also established that precipitation water, especially in the sparsely industrialised Włodawa region in the Lubelskie Voivodeship, had generally low pollution levels. It was also noted that in 2013, due to low total precipitation, the environmental impact of metal content was lower than in the preceding years.

  18. High-throughput computational search for strengthening precipitates in alloys

    International Nuclear Information System (INIS)

    Kirklin, S.; Saal, James E.; Hegde, Vinay I.; Wolverton, C.

    2016-01-01

    The search for high-strength alloys and precipitation hardened systems has largely been accomplished through Edisonian trial and error experimentation. Here, we present a novel strategy using high-throughput computational approaches to search for promising precipitate/alloy systems. We perform density functional theory (DFT) calculations of an extremely large space of ∼200,000 potential compounds in search of effective strengthening precipitates for a variety of different alloy matrices, e.g., Fe, Al, Mg, Ni, Co, and Ti. Our search strategy involves screening phases that are likely to produce coherent precipitates (based on small lattice mismatch) and are composed of relatively common alloying elements. When combined with the Open Quantum Materials Database (OQMD), we can computationally screen for precipitates that either have a stable two-phase equilibrium with the host matrix, or are likely to precipitate as metastable phases. Our search produces (for the structure types considered) nearly all currently known high-strength precipitates in a variety of fcc, bcc, and hcp matrices, thus giving us confidence in the strategy. In addition, we predict a number of new, currently-unknown precipitate systems that should be explored experimentally as promising high-strength alloy chemistries.

  19. Influence of aerosol on regional precipitation in North China

    Institute of Scientific and Technical Information of China (English)

    DUAN Jing; MAO JieTai

    2009-01-01

    The possible anthropogenic aerosol effect on regional precipitation is analyzed based on the historical data of precipitation and visibility of North China. At first, the precipitation amounts from 1960 to 1979 are considered as natural background values in our study for relatively less intensive industrial activi-ties and light air pollution during that period of time, then the region is divided into different subregions by applying the clustering method including the significance test of station rainfall correlations to the time series of 10-day mean rainfall amounts in this period. Based on the rule that the precipitation characteristics are similar in the same clustering region, the correlation of precipitation amounts among all stations in each region is thus established. Secondly, for the period from 1990 to 2005, during which, the economy had experienced a rapid development in this region, the variations of visibility at each station are analyzed. The stations with the absolute change in visibility less than 0.1 km/a are used as the reference stations, at which it is assumed that precipitation has not been seriously influ-enced by anthropogenic aerosols. Then the rainfall amounts of reference stations are used to estimate the natural precipitation values of the other stations in each clustering region. The difference between estimated precipitation and measured precipitation amount is thought to result from changes in an-thropogenic aerosols. These changes in precipitation amounts caused by anthropogenic aerosols at each station are calculated using the 10-day mean rainfall values from 1990 to 2005. The analysis re-suits obtained with this method are remarkable if it passes the significance test, and therefore, the suppression of regional precipitation over the region by anthropogenic aerosol is proved. It is found that this effect is most remarkable in summer. The influence of anthropogenic aerosols on convective precipitation possibly plays an important

  20. USSR Report Chemistry

    National Research Council Canada - National Science Library

    1986-01-01

    Contents: Adsorption, Chemistry,Alkaloids, Analytical Chemistry, Catalysis,Chemical Industry,,Coal Gasification, Combustion, Electrochemistry,Explosives and Explosions, Fertilizers, Free Radicals, Inorganic...

  1. Ozone Pollution

    Science.gov (United States)

    Known as tropospheric or ground-level ozone, this gas is harmful to human heath and the environment. Since it forms from emissions of volatile organic compounds (VOCs) and nitrogen oxides (NOx), these pollutants are regulated under air quality standards.

  2. Water Pollution

    Science.gov (United States)

    ... What is NIEHS Doing? Further Reading For Educators Introduction Water pollution is any contamination of water with ... NIEHS Newsletter) Karletta Chief Featured in Science Friday Film (April 2018) Chlorine Levels Help Detect Risk for ...

  3. Light Pollution

    Science.gov (United States)

    Riegel, Kurt W.

    1973-01-01

    Outdoor lighting is light pollution which handicaps certain astronomical programs. Protective measures must be adopted by the government to aid observational astronomy without sacrificing legitimate outdoor lighting needs. (PS)

  4. Precipitation Reconstruction (PREC)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The PREC data set is an analysis of monthly precipitation constructed on a 2.5(o)lat/lon grid over the global for the period from 1948 to the present. The land...

  5. Water chemistry

    International Nuclear Information System (INIS)

    Hofstetter, K.J.; Baston, V.F.

    1986-01-01

    Prior to the accident, the coolants in the primary and secondary systems were within normal chemistry specifications for an operating pressurized water reactor with once-through steam generators. During and immediately after the accident, additional boric acid and sodium hydroxide were added to the primary coolant for control of criticality and radioiodine solubility. A primary to secondary leak developed contaminating the water in one steam generator. For about 5 years after the accident, the primary coolant was maintained at 3800 +. 100 ppm boron and 1000 +. 100 ppm sodium concentrations. Dissolved oxygen was maintained 7.5, corrosion caused by increased dissolved oxygen levels (up to 8 ppm) and higher chloride ion content (up to 5 ppm) is minimized. Chemical control of dissolved oxygen was discontinued and the coolant was processed. Prior to removal of the reactor vessel head, the boron concentration in the coolant was increased to ≅ 5000 ppm to support future defueling operations. Decontamination of the accident generated water is described in terms of contaminated water management. In addition, the decontamination and chemical lay-up conditions for the secondary system are presented along with an overview of chemical management at TMI-2

  6. Air pollution

    International Nuclear Information System (INIS)

    Nelson, P.

    2000-01-01

    Australian cites experience a number of current and emerging air pollution problems. Concentrations of traditional primary pollutants such as CO, lead and dust have fallen in recent years as a consequence of air pollutant control measures, and the widespread introduction of lead-free petrol. However, recommended guidelines for ozone, the principal component of photochemical smog, are regularly exceeded in major capital cities in the summer months. In addition, it is predicted that extensive urban expansion will lead to much greater dependence on the motor vehicle as the primary means of transportation. Effects of air pollution are felt at a variety of scales. Traditionally, concerns about gaseous and particulate emissions from industrial and vehicular sources were focused on local impacts due to exposure to toxic species such as CO and lead. As noted above, concentrations of these pollutants have been reduced by a variety of control measures. Pollutants which have effects at a regional scale, such as photochemically-produced ozone, and acidic gases and particles have proved more difficult to reduce. In general, these pollutants arc not the result of direct emissions to atmosphere, but result from complex secondary processes driven by photochemical reactions of species such as NO 2 and aldehydes. In addition, global effects of gaseous and particulate emissions to the atmosphere have received significant recent attention, concentrations of atmospheric CO 2 with predicted impacts on global climate, and ozone depletion due to anthropogenic emissions of chlorine-containing chemicals are the two major examples. Combustion processes from petrol- and diesel-fuelled vehicles, make major contributions to air pollution, and the magnitude of this contribution is discussed in this article

  7. Modeling nitrogen chemistry in combustion

    DEFF Research Database (Denmark)

    Glarborg, Peter; Miller, James A.; Ruscic, Branko

    2018-01-01

    the accuracy of engineering calculations and thereby the potential of primary measures for NOx control. In this review our current understanding of the mechanisms that are responsible for combustion-generated nitrogen-containing air pollutants is discussed. The thermochemistry of the relevant nitrogen...... via NNH or N2O are discussed, along with the chemistry of NO removal processes such as reburning and Selective Non-Catalytic Reduction of NO. Each subset of the mechanism is evaluated against experimental data and the accuracy of modeling predictions is discussed....

  8. Ground Pollution Science

    International Nuclear Information System (INIS)

    Oh, Jong Min; Bae, Jae Geun

    1997-08-01

    This book deals with ground pollution science and soil science, classification of soil and fundamentals, ground pollution and human, ground pollution and organic matter, ground pollution and city environment, environmental problems of the earth and ground pollution, soil pollution and development of geological features of the ground, ground pollution and landfill of waste, case of measurement of ground pollution.

  9. F- and H-Area Seepage Basins Water Treatment System Process Optimization and Alternative Chemistry Ion Exchange/Sorbent Material Screening Clearwell Overflow Study

    Energy Technology Data Exchange (ETDEWEB)

    Serkiz, S.M.

    2000-08-30

    This study investigated alternative ion exchange/sorbent materials and polishing chemistries designed to remove specific radionuclides not removed during the neutralization/precipitation/clarification process.

  10. Pollution loads in urban runoff and sanitary wastewater.

    Science.gov (United States)

    Taebi, Amir; Droste, Ronald L

    2004-07-05

    While more attention has been paid in recent years to urban point source pollution control through the establishment of wastewater treatment plants in many developing countries, no considerable planning nor any serious measures have been taken to control urban non-point source pollution (urban stormwater runoff). The present study is a screening analysis to investigate the pollution loads in urban runoff compared to point source loads as a first prerequisite for planning and management of receiving water quality. To compare pollutant loads from point and non-point urban sources, the pollutant load is expressed as the weight of pollutant per hectare area per year (kg/ha.year). Unit loads were estimated in stormwater runoff, raw sanitary wastewater and secondary treatment effluents in Isfahan, Iran. Results indicate that the annual pollution load in urban runoff is lower than the annual pollution load in sanitary wastewater in areas with low precipitation but it is higher in areas with high precipitation. Two options, namely, advanced treatment (in lieu of secondary treatment) of sanitary wastewater and urban runoff quality control systems (such as detention ponds) were investigated as controlling systems for pollution discharges into receiving waters. The results revealed that for Isfahan, as a low precipitation urban area, advanced treatment is a more suitable option, but for high precipitation urban areas, urban surface runoff quality control installations were more effective for suspended solids and oxygen-demanding matter controls, and that advanced treatment is the more effective option for nutrient control.

  11. Pollution loads in urban runoff and sanitary wastewater

    International Nuclear Information System (INIS)

    Taebi, Amir; Droste, Ronald L.

    2004-01-01

    While more attention has been paid in recent years to urban point source pollution control through the establishment of wastewater treatment plants in many developing countries, no considerable planning nor any serious measures have been taken to control urban non-point source pollution (urban stormwater runoff). The present study is a screening analysis to investigate the pollution loads in urban runoff compared to point source loads as a first prerequisite for planning and management of receiving water quality. To compare pollutant loads from point and non-point urban sources, the pollutant load is expressed as the weight of pollutant per hectare area per year (kg/ha·year). Unit loads were estimated in stormwater runoff, raw sanitary wastewater and secondary treatment effluents in Isfahan, Iran. Results indicate that the annual pollution load in urban runoff is lower than the annual pollution load in sanitary wastewater in areas with low precipitation but it is higher in areas with high precipitation. Two options, namely, advanced treatment (in lieu of secondary treatment) of sanitary wastewater and urban runoff quality control systems (such as detention ponds) were investigated as controlling systems for pollution discharges into receiving waters. The results revealed that for Isfahan, as a low precipitation urban area, advanced treatment is a more suitable option, but for high precipitation urban areas, urban surface runoff quality control installations were more effective for suspended solids and oxygen-demanding matter controls, and that advanced treatment is the more effective option for nutrient control

  12. Environmental chemistry and ecotoxicology: in greater demand than ever.

    Science.gov (United States)

    Scheringer, Martin

    2017-01-01

    Environmental chemistry and ecotoxicology have been losing support, resources, and recognition at universities for many years. What are the possible causes of this process? A first problem may be that the need for research and teaching in environmental chemistry and ecotoxicology is no longer seen because chemical pollution problems are considered as largely solved. Second, environmental chemistry and ecotoxicology may be seen as fields dominated by routine work and where there are not many interesting research questions left. A third part of the problem may be that other environmental impacts such as climate change are given higher priority than chemical pollution problems. Here, several cases are presented that illustrate the great demand for innovative research and teaching in environmental chemistry and ecotoxicology. It is crucial that environmental chemistry and ecotoxicology are rooted in academic science and are provided with sufficient equipment, resources, and prospects for development.

  13. Electron tunneling in chemistry

    International Nuclear Information System (INIS)

    Zamaraev, K.I.; Khajrutdinov, R.F.; Zhdanov, V.P.; Molin, Yu.N.

    1985-01-01

    Results of experimental and theoretical investigations are outlined systematically on electron tunnelling in chemical reactions. Mechanism of electron transport to great distances is shown to be characteristic to chemical compounds of a wide range. The function of tunnel reactions is discussed for various fields of chemistry, including radiation chemistry, electrochemistry, chemistry of solids, chemistry of surface and catalysis

  14. Caracterización de la calidad de las aguas de la quebrada Fucha utilizando los índices de contaminación ICO con respecto a la precipitación y usos del suelo (Water quality characterization from creek Fucha using ICO pollution indices about precipitation and land use

    Directory of Open Access Journals (Sweden)

    Andrés Guillermo Chavarro

    2016-09-01

    Full Text Available Se presentan los resultados de la caracterización de la calidad de las aguas de la quebrada Fucha a través de los índices de contaminación ICO con respecto a los usos del suelo en diferentes épocas del año 2015. La quebrada se encuentra ubicada en la localidad de Usme, al suroriente de Bogotá (Colombia, en el límite urbano rural. Se midieron variables fisicoquímicas en seis muestreos y en tres puntos de la quebrada, se calcularon cuatro índices de contaminación (ICOMI, ICOMO, ICOSUS e ICOTRO; a estos se les realizó un análisis multivariado de correlación incluyendo la precipitación y los usos del suelo como variable indicador, se determinó el grado de correlación a través de regresiones simples para dos pares de variables. Adicionalmente se realizó un ANOVA con los usos del suelo y los valores obtenidos de los índices. No se encontró contaminación por mineralización y la quebrada en general presentó condiciones eutróficas, de igual manera se pudo establecer una correlación estadísticamente significativa entre la precipitación y el índice de contaminación trófica (ICOTRO, así como entre el índice de contaminación por sólidos suspendidos (ICOSUS e ICOTRO. Por su parte los usos del suelo no presentaron una correlación significativa con el aumento o disminución en el valor de los índices. (Abstract. The results of the characterization of the quality of water from the Fucha brook through ICO’s pollution indexes regarding land use at different times of the year are presented. The gorge is located in the town of Usme, in the urban-rural boundary. physic-chemical variables was measured in six samples and three points of the gorge, four indices of contamination (ICOMI, ICOMO, ICOSUS and ICOTRO were calculated, these were subjected to a multivariate correlation analysis including precipitation, it was determined the degree of correlation through simple regression for these two pairs of variables. In addition, an

  15. Magnetite precipitation and characterisation

    International Nuclear Information System (INIS)

    Joyce, A.; Garside, J.; Ivens, R.

    1988-06-01

    Magnetite (Fe 3 O 4 ) precipitation was investigated as a possible alternative treatment process to the conventional ferric hydroxide for removal of actinides from radioactive effluents. This offered the possibility of improved dewatering of filtered residues. Whilst a poor quality magnetite could be produced from deoxygenated ferrous/ferric solutions, all attempts to prepare magnetite from effluent simulates were unsuccessful. The failure was attributed to the presence of high nitrate and other interfering ions. (author)

  16. Precipitation in partially stabilized zirconia

    International Nuclear Information System (INIS)

    Bansal, G.K.

    1975-01-01

    Transmission electron microscopy was used to study the substructure of partially stabilized ZrO 2 (PSZ) samples, i.e., 2-phase systems containing both cubic and monoclinic modifications of zirconia, after various heat treatments. Monoclinic ZrO 2 exists as (1) isolated grains within the polycrystalline aggregate (a grain- boundary phase) and (2) small plate-like particles within cubic grains. These intragranular precipitates are believed to contribute to the useful properties of PSZ via a form of precipitation hardening. These precipitates initially form as tetragonal ZrO 2 , with a habit plane parallel to the brace 100 brace matrix planes. The orientation relations between the tetragonal precipitates and the cubic matrix are brace 100 brace/sub matrix/ 2 parallel brace 100 brace /sub precipitate/ or (001)/sub precipitate/ and broken bracket 100 broken bracket/sub matrix/ 2 parallel broken bracket 100 broken bracket/sub precipitate/ or [001]/sub precipitate/. (U.S.)

  17. Hourly Precipitation Data (HPD) Publication

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Hourly Precipitation Data (HPD) Publication is archived and available from the National Climatic Data Center (NCDC). This publication contains hourly precipitation...

  18. Air pollution

    International Nuclear Information System (INIS)

    Feugier, A.

    1996-01-01

    The air pollution results from the combustion of petroleum products, natural gas, coal, wastes and transports. Some compounds are considered as particularly pollutants: the carbon monoxide, the nitrogen oxides, the tropospheric ozone and the sulfur dioxides. Their environmental and biological effects are described. The present political guide lines concerns the combustion plants, the ozone, the wastes incineration and the vehicles emissions. The aim is at some future date to control the air quality, to reduce the volatile organic compounds emissions and to limit the sulfur rate of some petroleum products. (O.L.)

  19. ENVIRONMENTAL POLLUTION

    OpenAIRE

    Reyna Ramos, julio

    2014-01-01

    The article shows the complexity of the problem of environmental pollution and what can be the possible solutions to the problem. Also, how the Industrial Engineering can contribute to the prevention and control of pollution. El artículo muestra la complejidad del problema de la contaminación ambiental y cuáles pueden ser las propuestas de solución al problema. Así mismo, cómo la Ingeniería Industrial puede contribuir a la prevención y control de la contaminación.

  20. Tropospheric Halogen Chemistry

    Science.gov (United States)

    von Glasow, R.; Crutzen, P. J.

    2003-12-01

    Halogens are very reactive chemicals that are known to play an important role in anthropogenic stratospheric ozone depletion chemistry, first recognized by Molina and Rowland (1974). However, they also affect the chemistry of the troposphere. They are of special interest because they are involved in many reaction cycles that can affect the oxidation power of the atmosphere indirectly by influencing the main oxidants O3 and its photolysis product OH and directly, e.g., by reactions of the Cl radical with hydrocarbons (e.g., CH4).Already by the middle of the nineteenth century, Marchand (1852) reported the presence of bromine and iodine in rain and other natural waters. He also mentions the benefits of iodine in drinking water through the prevention of goitres and cretinism. In a prophetic monograph "Air and Rain: The Beginnings of a Chemical Climatology," Smith (1872) describes measurements of chloride in rain water, which he states to originate partly from the oceans by a process that he compares with the bursting of "soap bubbles" which produces "small vehicles" that transfer small spray droplets of seawater to the air. From deviations of the sulfate-to-chloride ratio in coastal rain compared to seawater, Smith concluded that chemical processes occur once the particles are airborne.For almost a century thereafter, however, atmospheric halogens received little attention. One exception was the work by Cauer (1939), who reported that iodine pollution has been significant in Western and Central Europe due to the inefficient burning of seaweed, causing mean gas phase atmospheric concentrations as high as or greater than 0.5 μg m-3. In his classical textbook Air Chemistry and Radioactivity, Junge (1963) devoted less than three pages to halogen gas phase chemistry, discussing chlorine and iodine. As reviewed by Eriksson (1959a, b), the main atmospheric source of halogens is sea salt, derived from the bursting of bubbles of air which are produced by ocean waves and other

  1. From hot atom chemistry to epithermal chemistry

    International Nuclear Information System (INIS)

    Roessler, K.

    2004-01-01

    The rise and fall of hot atom chemistry (HAC) over the years from 1934 to 2004 is reviewed. Several applications are discussed, in particular to astrophysics and the interaction of energetic ions and atoms in space. Epithermal chemistry (ETC) is proposed to substitute the old name, since it better fits the energy range as well as the non-thermal and non-equilibrium character of the reactions. ETC also avoids the strong connexion of HAC to nuclear chemistry and stands for the opening of the field to physical chemistry and astrophysics. (orig.)

  2. Ground water pollution through air pollutants

    International Nuclear Information System (INIS)

    Cichorowski, G.; Michel, B.; Versteegen, D.; Wettmann, R.

    1989-01-01

    The aim of the investigation is to determine the significance of air pollutants for ground water quality and ground water use. The report summarizes present knowledge and assesses statements with a view to potential ground water pollution from the air. In this context pollution paths, the spreading behaviour of pollutants, and 'cross points' with burden potentials from other pollutant sources are presented. (orig.) [de

  3. A Zooming Technique for Wind Transport of Air Pollution

    NARCIS (Netherlands)

    Berkvens, P.J.F.; Bochev, Mikhail A.; Lioen, W.; Verwer, J.G.

    In air pollution dispersion models, typically systems of millions of equations that describe wind transport, chemistry and vertical mixing have to be integrated in time. To have more accurate results over specific fixed areas of interest---usually highly polluted areas with intensive emissions---a

  4. A zooming technique for wind transport of air pollution

    NARCIS (Netherlands)

    Vilsmeier, R.; Berkvens, P.J.F.; Benkhaldoun, F.; Bochev, Mikhail A.; Lioen, W.M.; Haenel, D.; Verwer, J.G.

    1999-01-01

    In air pollution dispersion models, typically systems of millions of equations that describe wind transport, chemistry and vertical mixing have to be integrated in time. To have more accurate results over specific fixed areas of interest---usually highly polluted areas with intensive emissions---a

  5. Nuclear pollution

    International Nuclear Information System (INIS)

    Ramade, Francois

    1979-01-01

    In this chapter devoted to nuclear pollution the following topics were studied: fundamentals of radiobiology (ecological importance of the various radioisotopes, biological effects of ionizing radiations); ecological effects of radioactive fallout (contamination of atmosphere, terrestrial ecosystems, oceans). The electronuclear industry and its environmental impact. PWR type reactors, fuel reprocessing plants, contamination of trophic chains by radionuclides released in the environment from nuclear installations [fr

  6. Water Pollution

    Science.gov (United States)

    We all need clean water. People need it to grow crops and to operate factories, and for drinking and recreation. Fish and wildlife depend on ... and phosphorus make algae grow and can turn water green. Bacteria, often from sewage spills, can pollute ...

  7. Report on air quality and contribution of individual sources on its pollution in the Slovak Republic, 2001

    International Nuclear Information System (INIS)

    Mitosinkova, M.; Kozakovic, L.; Zavodsky, D.; Sajtakova, E.; Mareckova, K.; Pukancikova, K.

    2002-01-01

    A report on air quality and contribution of individual sources on its pollution in the Slovak Republic in 2001 is presented. This report consists of two parts: (1) Pollutants part and (2) Emission part. Pollutants part is divided into the following chapters: Regional air pollution and quality of precipitation; Local air pollution; Atmospheric ozone. Emission part is divided into the following chapters: Inventory control of emissions and sources of pollution, Emission of greenhouse gases. Emission limits are included

  8. A Polymer "Pollution Solution" Classroom Activity.

    Science.gov (United States)

    Helser, Terry L.

    1996-01-01

    Explains an approach to presenting polymer chemistry to nonmajors that employs polystyrene foam, foam peanuts made from water soluble starch, and water soluble plastic bags. Students are presented with a pollution scenario and are guided to the discovery of solutions. (DDR)

  9. Role of analytical chemistry in environmental monitoring

    International Nuclear Information System (INIS)

    Kayasth, S.; Swain, K.

    2004-01-01

    Basic aspects of pollution and the role of analytical chemistry in environmental monitoring are highlighted and exemplified, with emphasis on trace elements. Sources and pathways of natural and especially man-made polluting substances as well as physico-chemical characteristics are given. Attention is paid to adequate sampling in various compartments of the environment comprising both lithosphere and biosphere. Trace analysis is dealt with using a variety of analytical techniques, including criteria for choice of suited techniques, as well as aspects of analytical quality assurance and control. Finally, some data on trace elements levels in soil and water samples from India are presented. (author)

  10. The latest general chemistry

    International Nuclear Information System (INIS)

    Ryu, Geun Bae; Choi, Se Yeong; Kim, Chin Yeong; Yoon, Gil Jung; Lee, Eun Seok; Seo, Moon Gyu

    1995-02-01

    This book deals with the latest general chemistry, which is comprised of twenty-three chapters, the contents of this book are introduction, theory of atoms and molecule, chemical formula and a chemical reaction formula, structure of atoms, nature of atoms and the periodic table, structure of molecule and spectrum, gas, solution, solid, chemical combination, chemical reaction speed, chemical equilibrium, thermal chemistry, oxidation-reduction, electrochemistry, acid-base, complex, aquatic chemistry, air chemistry, nuclear chemistry, metal and nonmetal, organic chemistry and biochemistry. It has exercise in the end of each chapter.

  11. Constitutional dynamic chemistry: bridge from supramolecular chemistry to adaptive chemistry.

    Science.gov (United States)

    Lehn, Jean-Marie

    2012-01-01

    Supramolecular chemistry aims at implementing highly complex chemical systems from molecular components held together by non-covalent intermolecular forces and effecting molecular recognition, catalysis and transport processes. A further step consists in the investigation of chemical systems undergoing self-organization, i.e. systems capable of spontaneously generating well-defined functional supramolecular architectures by self-assembly from their components, thus behaving as programmed chemical systems. Supramolecular chemistry is intrinsically a dynamic chemistry in view of the lability of the interactions connecting the molecular components of a supramolecular entity and the resulting ability of supramolecular species to exchange their constituents. The same holds for molecular chemistry when the molecular entity contains covalent bonds that may form and break reversibility, so as to allow a continuous change in constitution by reorganization and exchange of building blocks. These features define a Constitutional Dynamic Chemistry (CDC) on both the molecular and supramolecular levels.CDC introduces a paradigm shift with respect to constitutionally static chemistry. The latter relies on design for the generation of a target entity, whereas CDC takes advantage of dynamic diversity to allow variation and selection. The implementation of selection in chemistry introduces a fundamental change in outlook. Whereas self-organization by design strives to achieve full control over the output molecular or supramolecular entity by explicit programming, self-organization with selection operates on dynamic constitutional diversity in response to either internal or external factors to achieve adaptation.The merging of the features: -information and programmability, -dynamics and reversibility, -constitution and structural diversity, points to the emergence of adaptive and evolutive chemistry, towards a chemistry of complex matter.

  12. Wet deposition at the base of Mt Everest: Seasonal evolution of the chemistry and isotopic composition

    Science.gov (United States)

    Balestrini, Raffaella; Delconte, Carlo A.; Sacchi, Elisa; Wilson, Alana M.; Williams, Mark W.; Cristofanelli, Paolo; Putero, Davide

    2016-12-01

    The chemistry of wet deposition was investigated during 2012-2014 at the Pyramid International Laboratory in the Upper Khumbu Valley, Nepal, at 5050 m a.s.l., within the Global Atmosphere Watch (GAW) programme. The main hydro-chemical species and stable isotopes of the water molecule were determined for monsoon rain (July-September) and snow samples (October-June). To evaluate the synoptic-scale variability of air masses reaching the measurement site, 5 day back-trajectories were computed for the sampling period. Ion concentrations in precipitation during the monsoon were low suggesting that they represent global regional background concentrations. The associations between ions suggested that the principal sources of chemical species were marine aerosols, rock and soil dust, and fossil fuel combustion. Most chemical species exhibited a pattern during the monsoon, with maxima at the beginning and at the end of the season, partially correlated with the precipitation amount. Snow samples exhibited significantly higher concentrations of chemical species, compared to the monsoon rainfall observations. Particularly during 2013, elevated concentrations of NO3-, SO42- and NH4+ were measured in the first winter snow event, and in May at the end of the pre-monsoon season. The analysis of large-scale circulation and wind regimes as well as atmospheric composition observations in the region indicates the transport of polluted air masses from the Himalayan foothills and Indian sub-continent up to the Himalaya region. During the summer monsoon onset period, the greater values of pollutants can be attributed to air-mass transport from the planetary boundary layer (PBL) of the Indo-Gangetic plains. Isotopic data confirm that during the monsoon period, precipitation occurred from water vapor that originated from the Indian Ocean and the Bay of Bengal; by contrast during the non-monsoon period, an isotopic signature of more continental origin appeared, indicating that the higher

  13. Considerations of stationary-phase interactions in groundwater pollution studies

    International Nuclear Information System (INIS)

    Hall, E.S.

    1980-01-01

    Studies of groundwater pollution are complicated by retention of both pollutant and tracers as static phases associated with the rock matrix. Three types of static phase are considered: (1) immobile pore water, (2) equilibrium adsorbed layers and (3) bulk precipitates, including biological systems. A brief discussion of the systems is given with examples from the work of the Water Research Centre on the problems encountered in quantifying groundwater pollution where static contamination may occur. (author)

  14. DISSOLUTION OF LANTHANUM FLUORIDE PRECIPITATES

    Science.gov (United States)

    Fries, B.A.

    1959-11-10

    A plutonium separatory ore concentration procedure involving the use of a fluoride type of carrier is presented. An improvement is given in the derivation step in the process for plutonium recovery by carrier precipitation of plutonium values from solution with a lanthanum fluoride carrier precipitate and subsequent derivation from the resulting plutonium bearing carrier precipitate of an aqueous acidic plutonium-containing solution. The carrier precipitate is contacted with a concentrated aqueous solution of potassium carbonate to effect dissolution therein of at least a part of the precipitate, including the plutonium values. Any remaining precipitate is separated from the resulting solution and dissolves in an aqueous solution containing at least 20% by weight of potassium carbonate. The reacting solutions are combined, and an alkali metal hydroxide added to a concentration of at least 2N to precipitate lanthanum hydroxide concomitantly carrying plutonium values.

  15. A novel electrostatic precipitator

    International Nuclear Information System (INIS)

    Tang, Minkang; Wang, Liqian; Lin, Zhigui

    2013-01-01

    ESP (Electrostatic Precipitation) has been widely used in the mining, building materials, metallurgy and power industries. Dust particles or other harmful particles from the airstream can be precipitated by ESP with great collecting efficiency. Because of its' large size, high cost and energy consumption, the scope of application of ESP has been limited to a certain extent. By means of the theory of electrostatics and fluid dynamics, a corona assembly with a self-cleaning function and a threshold voltage automatic tracking technology has been developed and used in ESP. It is indicated that compared with conventional ESP, the electric field length has been reduced to 1/10 of the original, the current density on the collecting electrode increased 3-5 times at the maximum, the approach speed of dust particles in the electric field towards the collecting electrode is 4 times that in conventional ESP and the electric field wind speed may be enhanced by 2-3 times the original. Under the premise of ESP having a high efficiency of dust removal, equipment volume may be actually reduced to 1/5 to 1/10 of the original volume and energy consumption may be reduced by more than 50%.

  16. Study of the pollution exchange between Bulgaria and Northern Greece

    International Nuclear Information System (INIS)

    Zerefos, C.; Vasaras, A.; Syrakov, D.; Ganev, K.

    2000-01-01

    The present work aims at a detailed study and explanation of the pollution transport in the air basin over South-Western Bulgaria and Northern Greece and assessment of the air pollution exchange between Bulgaria and Greece. Some well known specific climatic air pollution effects were studied and explained. Calculations were made of the S0 2 pollution of the Balkan peninsula from both Greek and Bulgarian sources for 1995 and the country to country pollution budget diagrams were build. Days with extreme mean concentration for Bulgaria and Northern Greece were picked out and some further specification of the contribution of the different sources in both the countries to these cases of extreme pollution was made. Some preliminary studies of possible mesoscale effects on the pollution exchange between Bulgaria and northern Greece were carried out. A three-layer pollution transport model with more complex chemistry block was introduced and some preliminary simulations of Sulfur and Nitrogen compounds transport were performed. (author)

  17. Advanced Chemistry Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — Description/History: Chemistry laboratoryThe Advanced Chemistry Laboratory (ACL) is a unique facility designed for working with the most super toxic compounds known...

  18. Electrostatics in Chemistry

    Indian Academy of Sciences (India)

    fundamental concepts of electrostatics as applied to atoms and molecules. The electric ... chemistry, the chemistry of the covalent bond, deals with the structures ..... the position of an asteroid named Ceres ... World Scientific. Singapore, 1992.

  19. The Internet Pollution

    Institute of Scientific and Technical Information of China (English)

    唐宁宁

    2005-01-01

    Life today has brought new problems. As we know, there are fourterrible pollutions in the world: water pollution, noise pollution, air pol-lution and rubbish pollution. Water pollution kills our fish and pollutesour drinking water. Noise pollution makes us talk louder and become angry more easily. Air pollution makes us hold our breath longer and be badto all living things in the world. Rubbish pollution often makes our livingenvironment much dirtier. But I think that the Internet pollution is anothernew pollution in the world.

  20. The Global Precipitation Climatology Project (GPCP) Combined Precipitation Dataset

    Science.gov (United States)

    Huffman, George J.; Adler, Robert F.; Arkin, Philip; Chang, Alfred; Ferraro, Ralph; Gruber, Arnold; Janowiak, John; McNab, Alan; Rudolf, Bruno; Schneider, Udo

    1997-01-01

    The Global Precipitation Climatology Project (GPCP) has released the GPCP Version 1 Combined Precipitation Data Set, a global, monthly precipitation dataset covering the period July 1987 through December 1995. The primary product in the dataset is a merged analysis incorporating precipitation estimates from low-orbit-satellite microwave data, geosynchronous-orbit -satellite infrared data, and rain gauge observations. The dataset also contains the individual input fields, a combination of the microwave and infrared satellite estimates, and error estimates for each field. The data are provided on 2.5 deg x 2.5 deg latitude-longitude global grids. Preliminary analyses show general agreement with prior studies of global precipitation and extends prior studies of El Nino-Southern Oscillation precipitation patterns. At the regional scale there are systematic differences with standard climatologies.

  1. Pollution law

    International Nuclear Information System (INIS)

    Triffterer, O.

    1980-01-01

    In the draft proposed by the legal advisory board the law for the controlling of environmental criminality was promulgated on 28th March 1980. The present commentary therefore - as seen from the results - corresponds in essential to the original assessment of the governmental draft. However, an introduction into the problems of environmental law precedes this commentary for the better unterstanding of all those not acquainted with pollution law and the whole legal matter. (orig./HP) [de

  2. Radioactive pollution

    International Nuclear Information System (INIS)

    Steiner, R.

    1987-01-01

    In the wake of the Chernobyl reactor accident on April 26, 1986, many individual values for radioactivity in the air, in foodstuffs and in the soil were measured and published. Prof. Dr. Rolf Steiner, Wiesbaden, the author of this paper, evaluated the host of data - mostly official pollution data -, drew conclusions regarding the radioactivity actually released at Chernobyl, and used the data to test the calculation model adotped by the Radiation Protection Ordinance. (orig./RB) [de

  3. Preparative radiation chemistry

    International Nuclear Information System (INIS)

    Drawe, H.

    1978-01-01

    Preparative synthesis of compounds with the aid of radiation chemistry is increasingly used in laboratories as well as on a technical scale. A large number of new compounds has been produced with the methods of radiation chemistry. With the increasing number of available radiation sources, also the number of synthesis metods in radiation chemistry has increased. This paper can only briefly mention the many possible ways of synthesis in radiation chemistry. (orig./HK) [de

  4. USSR Report Chemistry

    National Research Council Canada - National Science Library

    1986-01-01

    THIS REPORT CONTAINS FOREIGN MEDIA INFORMATION FROM THE USSR CONCERNING Adsorption, Alkaloids, ANALYTICAL CHEMISTRY, CATALYSIS, ELECTROCHEMISTRY, Fertilizers, INORGANIC COMPOUNDS, ORGANOPHOSPHOROUS...

  5. Frontiers in Gold Chemistry

    OpenAIRE

    Ahmed A. Mohamed

    2015-01-01

    Basic chemistry of gold tells us that it can bond to sulfur, phosphorous, nitrogen, and oxygen donor ligands. The Frontiers in Gold Chemistry Special Issue covers gold complexes bonded to the different donors and their fascinating applications. This issue covers both basic chemistry studies of gold complexes and their contemporary applications in medicine, materials chemistry, and optical sensors. There is a strong belief that aurophilicity plays a major role in the unending applications of g...

  6. Organic chemistry experiment

    International Nuclear Information System (INIS)

    Mun, Seok Sik

    2005-02-01

    This book deals with organic chemistry experiments, it is divided five chapters, which have introduction, the way to write the experiment report and safety in the laboratory, basic experiment technic like recrystallization and extraction, a lot of organic chemistry experiments such as fischer esterification, ester hydrolysis, electrophilic aromatic substitution, aldol reaction, benzoin condensation, wittig reaction grignard reaction, epoxidation reaction and selective reduction. The last chapter introduces chemistry site on the internet and way to find out reference on chemistry.

  7. Alcohol combustion chemistry

    KAUST Repository

    Sarathy, Mani

    2014-10-01

    Alternative transportation fuels, preferably from renewable sources, include alcohols with up to five or even more carbon atoms. They are considered promising because they can be derived from biological matter via established and new processes. In addition, many of their physical-chemical properties are compatible with the requirements of modern engines, which make them attractive either as replacements for fossil fuels or as fuel additives. Indeed, alcohol fuels have been used since the early years of automobile production, particularly in Brazil, where ethanol has a long history of use as an automobile fuel. Recently, increasing attention has been paid to the use of non-petroleum-based fuels made from biological sources, including alcohols (predominantly ethanol), as important liquid biofuels. Today, the ethanol fuel that is offered in the market is mainly made from sugar cane or corn. Its production as a first-generation biofuel, especially in North America, has been associated with publicly discussed drawbacks, such as reduction in the food supply, need for fertilization, extensive water usage, and other ecological concerns. More environmentally friendly processes are being considered to produce alcohols from inedible plants or plant parts on wasteland. While biofuel production and its use (especially ethanol and biodiesel) in internal combustion engines have been the focus of several recent reviews, a dedicated overview and summary of research on alcohol combustion chemistry is still lacking. Besides ethanol, many linear and branched members of the alcohol family, from methanol to hexanols, have been studied, with a particular emphasis on butanols. These fuels and their combustion properties, including their ignition, flame propagation, and extinction characteristics, their pyrolysis and oxidation reactions, and their potential to produce pollutant emissions have been intensively investigated in dedicated experiments on the laboratory and the engine scale

  8. Optimization of precipitation conditions of thorium oxalate precipitate

    International Nuclear Information System (INIS)

    Pazukhin, Eh.M.; Smirnova, E.A.; Krivokhatskij, A.S.; Pazukhina, Yu.L.; Kiselev, P.P.

    1986-01-01

    Thorium precipitation in the form of difficultly soluble oxalate has been investigated. The equation binding the concentration of metal with the nitric acid in the initial solution and quantity of a precipitator necessary for minimization of desired product losses is derived. The graphical solution of this equation for a case, when the oxalic acid with 0.78 mol/l concentration is the precipitator, is presented

  9. Analytical chemistry instrumentation

    International Nuclear Information System (INIS)

    Laing, W.R.

    1986-01-01

    In nine sections, 48 chapters cover 1) analytical chemistry and the environment 2) environmental radiochemistry 3) automated instrumentation 4) advances in analytical mass spectrometry 5) fourier transform spectroscopy 6) analytical chemistry of plutonium 7) nuclear analytical chemistry 8) chemometrics and 9) nuclear fuel technology

  10. Fundamentals of nuclear chemistry

    International Nuclear Information System (INIS)

    Majer, V.

    1982-01-01

    The author of the book has had 25 years of experience at the Nuclear Chemistry of Prague Technical University. In consequence, the book is intended as a basic textbook for students of this field. Its main objectives are an easily understandable presentation of the complex subject and in spite of the uncertainty which still characterizes the definition and subjects of nuclear chemistry - a systematic classification and logical structure. Contents: 1. Introduction (history and definition); 2. General nuclear chemistry (physical fundamentals, hot atom chemistry, interaction of nuclear radiation with matter, radioactive elements, isotope effects, isotope exchange, chemistry of radioactive trace elements); 3. Methods of nuclear chemistry of nuclear chemistry (radiochemical methods, activation, separation and enrichment chemistry); 4. Preparative nuclear chemistry (isotope production, labelled compounds); 5. Analytival nuclear chemistry; 6. Applied nuclear chemistry (isotope applications in general physical and analytical chemistry). The book is supplemented by an annex with tables, a name catalogue and a subject index which will facilitate access to important information. (RB) [de

  11. Upgrading of electrostatic precipitators in old thermal power plant

    Energy Technology Data Exchange (ETDEWEB)

    Gurumurthy, H V

    1987-02-01

    Indian thermal power stations installed in the 60's and earlier had dust collectors whose efficiency was well below the acceptable level of emission under the Air (Prevention and Control of Pollution) Act 1981. This necessitates the need for higher efficiency dust collectors to be installed in old thermal power stations. Further, the poor quality of the coal being received at power stations presently causes severe environmental pollution in and around the plant. This paper deals with the retrofitting of electrostatic precipitators in existing units and the problems encountered in executing the same.

  12. Water Pollution. Project COMPSEP.

    Science.gov (United States)

    Lantz, H. B., Jr.

    This is an introductory program on water pollution. Examined are the cause and effect relationships of water pollution, sources of water pollution, and possible alternatives to effect solutions from our water pollution problems. Included is background information on water pollution, a glossary of pollution terminology, a script for a slide script…

  13. Enzymes - important players in green chemistry

    Directory of Open Access Journals (Sweden)

    Agata Tarczykowska

    2017-09-01

    Full Text Available Green chemistry has become a worldwide approach that leads to sustainable growth through application and development of its principles. A lot of work has to be put into designing new processes comprising of materials which do not emit pollutants to the atmosphere. Inventing new safer methods and finding less harmful products can be challenging. Enzymes are a great hope of scientists in the field of green chemistry. Enzymes as catalysts require mild conditions therefore it is a great way of saving resources such as energy or water. Processes with the use of enzymes have become more feasible by being more cost effective and eco friendly. Taking into account the benefits of green chemistry, enzyme biocatalysis has quickly replaced traditional chemical processes in several fields, and this substitution is going to reach even more areas because of new emerging technologies in enzyme engineering.

  14. American Association for Clinical Chemistry

    Science.gov (United States)

    ... Find the answer to your question IN CLINICAL CHEMISTRY Hs-cTnI as a Gatekeeper for Further Cardiac ... Online Harmonization.net Commission on Accreditation in Clinical Chemistry American Board of Clinical Chemistry Clinical Chemistry Trainee ...

  15. The New Color of Chemistry: Green Chemistry

    Directory of Open Access Journals (Sweden)

    Zuhal GERÇEK

    2012-01-01

    Full Text Available Green chemistry which is the new application of chemistry rules provides solutions to problems that mankind is faced with climate changes, sustainable agriculture, energy, toxics, depletion of natural sources e.g. designing new chemicals and processes that production and utilization of hazardous matters. So, it is the indispensible tool for sustainable development. Current and future chemists should consider the human health and ecological issues in their professional life. In order to provide a solution for this requirement, green chemistry rules and under standings should be primarily taken in the university curriculum and at all educational levels.

  16. Two-stage precipitation of plutonium trifluoride

    International Nuclear Information System (INIS)

    Luerkens, D.W.

    1984-04-01

    Plutonium trifluoride was precipitated using a two-stage precipitation system. A series of precipitation experiments identified the significant process variables affecting precipitate characteristics. A mathematical precipitation model was developed which was based on the formation of plutonium fluoride complexes. The precipitation model relates all process variables, in a single equation, to a single parameter that can be used to control particle characteristics

  17. Surface chemistry essentials

    CERN Document Server

    Birdi, K S

    2013-01-01

    Surface chemistry plays an important role in everyday life, as the basis for many phenomena as well as technological applications. Common examples range from soap bubbles, foam, and raindrops to cosmetics, paint, adhesives, and pharmaceuticals. Additional areas that rely on surface chemistry include modern nanotechnology, medical diagnostics, and drug delivery. There is extensive literature on this subject, but most chemistry books only devote one or two chapters to it. Surface Chemistry Essentials fills a need for a reference that brings together the fundamental aspects of surface chemistry w

  18. Fundamentals of reactor chemistry

    International Nuclear Information System (INIS)

    Akatsu, Eiko

    1981-12-01

    In the Nuclear Engineering School of JAERI, many courses are presented for the people working in and around the nuclear reactors. The curricula of the courses contain also the subject material of chemistry. With reference to the foreign curricula, a plan of educational subject material of chemistry in the Nuclear Engineering School of JAERI was considered, and the fundamental part of reactor chemistry was reviewed in this report. Since the students of the Nuclear Engineering School are not chemists, the knowledge necessary in and around the nuclear reactors was emphasized in order to familiarize the students with the reactor chemistry. The teaching experience of the fundamentals of reactor chemistry is also given. (author)

  19. Effective Assimilation of Global Precipitation

    Science.gov (United States)

    Lien, G.; Kalnay, E.; Miyoshi, T.; Huffman, G. J.

    2012-12-01

    Assimilating precipitation observations by modifying the moisture and sometimes temperature profiles has been shown successful in forcing the model precipitation to be close to the observed precipitation, but only while the assimilation is taking place. After the forecast start, the model tends to "forget" the assimilation changes and lose their extra skill after few forecast hours. This suggests that this approach is not an efficient way to modify the potential vorticity field, since this is the variable that the model would remember. In this study, the ensemble Kalman filter (EnKF) method is used to effectively change the potential vorticity field by allowing ensemble members with better precipitation to receive higher weights. In addition to using an EnKF, two other changes in the precipitation assimilation process are proposed to solve the problems related to the highly non-Gaussian nature of the precipitation variable: a) transform precipitation into a Gaussian distribution based on its climatological distribution, and b) only assimilate precipitation at the location where some ensemble members have positive precipitation. The idea is first tested by the observing system simulation experiments (OSSEs) using SPEEDY, a simplified but realistic general circulation model. When the global precipitation is assimilated in addition to conventional rawinsonde observations, both the analyses and the medium range forecasts are significantly improved as compared to only having rawinsonde observations. The improvement is much reduced when only modifying the moisture field with the same approach, which shows the importance of the error covariance between precipitation and all other model variables. The effect of precipitation assimilation is larger in the Southern Hemisphere than that in the Northern Hemisphere because the Northern Hemisphere analyses are already accurate as a result of denser rawinsonde stations. Assimilation of precipitation using a more comprehensive

  20. Electrical operation of electrostatic precipitators

    CERN Document Server

    Parker, Ken

    2003-01-01

    The electrostatic precipitator remains on of the most cost effective means of controlling the emission of particulates from most industrial processes. This book will be of interest to both users and suppliers of electrostatic precipitators as well as advanced students on environmental based courses. The author identifies the physical and engineering basis for the development of electrical equipment for electrostatic precipitators and thoroughly explores the technological factors which optimize the efficiency of the precipitator and hence minimize emissions, as well as future developments in th

  1. Annual report 1985 Chemistry Department

    International Nuclear Information System (INIS)

    Funck, J.; Larsen, E.; Nielsen, O.J.

    1986-03-01

    This report contains a brief survey of the main activities in the Chemistry Department. All particles and reports published and lectures given in 1985 are presented. The facilities and equipment are mentioned briefly. The activities are divided into the following groups: radioisotope chemistry, analytical- and organic chemistry, environmental chemistry, polymer chemistry, geochemistry and waste disposal, radical chemistry, positron annihilation, mineral processing, and general. (author)

  2. Annual report 1984 Chemistry Department

    International Nuclear Information System (INIS)

    Funck, J.; Larsen, E.; Nielsen, O.J.

    1985-03-01

    This report contains a brief survey of the main activities in the Chemistry Department. All articles and reports published and lectures given in 1984 are presented. The facilities and equipment are mentioned briefly. The activities are divided into the following groups: radioisotope chemistry, analytical- and organic chemistry , environmental chemistry, polymer chemistry, geochemistry and waste disposal, radical chemistry, positron annihilation, mineral processing, and general. (author)

  3. Fundamentals of nuclear chemistry

    International Nuclear Information System (INIS)

    Matel, L.; Dulanska, S.

    2013-01-01

    This text-book is an introductory text in nuclear chemistry and radiochemistry, aimed on university undergraduate students in chemistry and related disciplines (physics, nuclear engineering). It covers the key aspects of modern nuclear chemistry. The text begins with basic theories in contemporary physics. It relates nuclear phenomena to key divisions of chemistry such as atomic structure, spectroscopy, equilibria and kinetics. It also gives an introduction to sources of ionizing radiation, detection of ionizing radiation, nuclear power industry and accident on nuclear installations as well as basic knowledge's of radiobiology. This book is essential reading for those taking a first course in nuclear chemistry and is a useful companion to other volumes in physical and analytical chemistry. It will also be of use to those new to working in nuclear chemistry or radiochemistry.

  4. Radioactive pollution

    International Nuclear Information System (INIS)

    Pohl, R.O.

    1976-01-01

    The widely published claims that the public health effects resulting from routine emissions are between 0.01 and 0.1 serious health effects per gigawattyear, and hence are at least a thousand times smaller than those resulting from air pollution by the burning of coal, cannot be true, for two reasons. The authors of these claims have ignored at least two of the more important isotopes, radon-222 and carbon-14, which are presently released to the environment, and thus contribute greatly to the health impact of nuclear energy. The health effects calculated in the earlier work cover only those which occur during the year in which the energy is generated. This means, figuratively speaking, that the authors have confused an annual installment payment with the full cost. This is unacceptable. The contribution to the health impact of nuclear energy arising from the single isotopic species radon-222 emanating from the mill tailings is estimated to 400 lung cancer deaths/GW(e)y, larger even than the most pessimistic estimates of the health impact of energy from coal through atmospheric pollution. We have no assurance that other long-lived isotopes do not contribute comparable amounts to the health impact of nuclear energy. The discussion of the health impact of radon-222 raises the fundamental moral question--how far into the future our responsibility extends. If such a long-termresponsibility is rejected, then we must at least try to predict the environmental buildup of radioactive pollutants, in order to avoid unacceptable and irreversible levels of radiation dose rate. The potential health consequences from long-lived radioisotopes seem to have been largely ignored so far, and should be explored in detail

  5. Indoor Air Pollution (Environmental Health Student Portal)

    Science.gov (United States)

    ... Students to Environmental Health Information Menu Home Air Pollution Air Pollution Home Indoor Air Pollution Outdoor Air Pollution ... Pollution Indoor Air Pollution Print this Page Air Pollution Air Pollution Home Indoor Air Pollution Outdoor Air Pollution ...

  6. Probing planetary pollution from space

    International Nuclear Information System (INIS)

    Fishman, J.

    1991-01-01

    This paper will review the data sets obtained from instruments that have measured carbon monoxide and tropospheric ozone from space. In addition, an example of the capability of Differential Absorption Lidar (DIAL) systems will be shown and the current plans for monitoring pollution from spaceborne platforms will be discussed. As a result of these studies, scientists now know that pollution is a widespread phenomenon that has impacted the composition of the atmosphere on continental and hemispheric scales. Such perturbations will have far-reaching consequences for global atmospheric chemistry and climate. New measurement techniques using active remote sensors have already produced exciting data sets from aircraft platforms, and should provide an entirely new capability when used from space sometime in the 21st century

  7. Summary report on groundwater chemistry

    International Nuclear Information System (INIS)

    Lampen, P.; Snellman, M.

    1993-07-01

    The preliminary site investigations for radioactive waste disposal (in Finland) carried out by Teollisuuden Voima Oy (TVO) during the period 1987 to 1992 yielded data on hydrogeochemistry from a total 337 water samples. The main objective of the groundwater chemistry studies was to characterize groundwaters at the investigation sites and, specifically, to create a concept for the mean residence times and evolution of groundwater by means of isotopic analyses. Moreover, the studies yielded input data for geochemical modelling and the performance assessment. Samples were taken from deep boreholes (with a depth of 500 to 1000 m), percussion-drilled boreholes (depth approx. 200 m), flushing-water wells (approx. 100 m) and multi-level pietzometers (approx. 100 m) used in the hydrological tests. The water used for drilling the deep boreholes was taken from local flushing-water wells, whose water was also analyzed in detail. The flushing water used in drilling was marked with two tracers, iodine and uranine, analyzed with two different methods. For reference purposes, samples were also taken from surficial and groundwaters over a large area surrounding the investigation site. Precipitation over a period of at least one year was collected at all the five investigation sites and the samples were analyzed in great detail, particularly with regard to isotopes. Similarly, snow profile samples representing precipitation during the entire winter was taken from each site at least once

  8. Nuclear chemistry in the traditional chemistry program

    International Nuclear Information System (INIS)

    Kleppinger, E.W.

    1993-01-01

    The traditional undergraduate program for chemistry majors, especially at institutions devoted solely to undergraduate education, has limited space for 'special topics' courses in areas such as nuclear and radiochemistry. A scheme is proposed whereby the basic topics covered in an introductury radiochemistry course are touched upon, and in some cases covered in detail, at some time during the four-year sequence of courses taken by a chemistry major. (author) 6 refs.; 7 tabs

  9. The New Color of Chemistry: Green Chemistry

    OpenAIRE

    Zuhal GERÇEK

    2012-01-01

    Green chemistry which is the new application of chemistry rules provides solutions to problems that mankind is faced with climate changes, sustainable agriculture, energy, toxics, depletion of natural sources e.g. designing new chemicals and processes that production and utilization of hazardous matters. So, it is the indispensible tool for sustainable development. Current and future chemists should consider the human health and ecological issues in their professional life. In order to provid...

  10. Characterizing Normal Groundwater Chemistry in Hawaii

    Science.gov (United States)

    Tachera, D.; Lautze, N. C.; Thomas, D. M.; Whittier, R. B.; Frazer, L. N.

    2017-12-01

    Hawaii is dependent on groundwater resources, yet how water moves through the subsurface is not well understood in many locations across the state. As marine air moves across the islands water evaporates from the ocean, along with trace amounts of sea-salt ions, and interacts with the anthropogenic and volcanic aerosols (e.g. sulfuric acid, ammonium sulfate, HCl), creating a slightly more acidic rain. When this rain falls, it has a chemical signature distinctive of past processes. As this precipitation infiltrates through soil it may pick up another distinctive chemical signature associated with land use and degree of soil development, and as it flows through the underlying geology, its chemistry is influenced by the host rock. We are currently conducting an investigation of groundwater chemistry in selected aquifer areas of Hawaii, having diverse land use, land cover, and soil development conditions, in an effort to investigate and document what may be considered a "normal" water chemistry for an area. Through this effort, we believe we better assess anomalies due to contamination events, hydrothermal alteration, and other processes; and we can use this information to better understand groundwater flow direction. The project has compiled a large amount of precipitation, soil, and groundwater chemistry data in the three focus areas distributed across in the State of Hawaii. Statistical analyses of these data sets will be performed in an effort to determine what is "normal" and what is anomalous chemistry for a given area. Where possible, results will be used to trace groundwater flow paths. Methods and preliminary results will be presented.

  11. The Relationships Between Insoluble Precipitation Residues, Clouds, and Precipitation Over California's Southern Sierra Nevada During Winter Storms

    Science.gov (United States)

    Creamean, Jessie M.; White, Allen B.; Minnis, Patrick; Palikonda, Rabindra; Spangenberg, Douglas A.; Prather, Kimberly A.

    2016-01-01

    Ice formation in orographic mixed-phase clouds can enhance precipitation and depends on the type of aerosols that serve as ice nucleating particles (INP). The resulting precipitation from these clouds is a viable source of water, especially for regions such as the California Sierra Nevada. Thus, a better understanding of the sources of INP that impact orographic clouds is important for assessing water availability in California. This study presents a multi-site, multi-year analysis of single particle insoluble residues in precipitation samples that likely influenced cloud ice and precipitation formation above Yosemite National Park. Dust and biological particles represented the dominant fraction of the residues (64% on average). Cloud glaciation, determined using GOES satellite observations, not only depended on high cloud tops (greater than 6.2 km) and low temperatures (less than -26 C), but also on the composition of the dust and biological residues. The greatest prevalence of ice-phase clouds occurred in conjunction with biologically-rich residues and mineral dust rich in calcium, followed by iron and aluminosilicates. Dust and biological particles are known to be efficient INP, thus these residues are what likely influenced ice formation in clouds above the sites and subsequent precipitation quantities reaching the surface during events with similar meteorology. The goal of this study is to use precipitation chemistry information to gain a better understanding of the potential sources of INP in the south-central Sierra Nevada, where cloud-aerosol-precipitation interactions are under-studied and where mixed-phase orographic clouds represent a key element in the generation of precipitation and thus the water supply in California.

  12. Understanding the mobilisation of metal pollution associated with historical mining in a carboniferous upland catchment.

    Science.gov (United States)

    Valencia-Avellan, Magaly; Slack, Rebecca; Stockdale, Anthony; Mortimer, Robert John George

    2017-08-16

    Point and diffuse pollution from metal mining has led to severe environmental damage worldwide. Mine drainage is a significant problem for riverine ecosystems, it is commonly acidic (AMD), but neutral mine drainage (NMD) can also occur. A representative environment for studying metal pollution from NMD is provided by carboniferous catchments characterised by a circumneutral pH and high concentrations of carbonates, supporting the formation of secondary metal-minerals as potential sinks of metals. The present study focuses on understanding the mobility of metal pollution associated with historical mining in a carboniferous upland catchment. In the uplands of the UK, river water, sediments and spoil wastes were collected over a period of fourteen months, samples were chemically analysed to identify the main metal sources and their relationships with geological and hydrological factors. Correlation tests and principal component analysis suggest that the underlying limestone bedrock controls pH and weathering reactions. Significant metal concentrations from mining activities were measured for zinc (4.3 mg l -1 ), and lead (0.3 mg l -1 ), attributed to processes such as oxidation of mined ores (e.g. sphalerite, galena) or dissolution of precipitated secondary metal-minerals (e.g. cerussite, smithsonite). Zinc and lead mobility indicated strong dependence on biogeochemistry and hydrological conditions (e.g. pH and flow) at specific locations in the catchment. Annual loads of zinc and lead (2.9 and 0.2 tonnes per year) demonstrate a significant source of both metals to downstream river reaches. Metal pollution results in a large area of catchment having a depleted chemical status with likely effects on the aquatic ecology. This study provides an improved understanding of geological and hydrological processes controlling water chemistry, which is critical to assessing metal sources and mobilization, especially in neutral mine drainage areas.

  13. Improving precipitation measurement

    Science.gov (United States)

    Strangeways, Ian

    2004-09-01

    Although rainfall has been measured for centuries scientifically and in isolated brief episodes over millennia for agriculture, it is still not measured adequately even today for climatology, water resources, and other precise applications. This paper outlines the history of raingauges, their errors, and describes the field testing over 3 years of a first guess design for an aerodynamic rain collector proposed by Folland in 1988. Although shown to have aerodynamic advantage over a standard 5 gauge, the new rain collector was found to suffer from outsplash in heavy rain. To study this problem, and to derive general basic design rules for aerodynamic gauges, its performance was investigated in turbulent, real-world conditions rather than in the controlled and simplified environment of a wind tunnel or mathematical model as in the past. To do this, video records were made using thread tracers to indicate the path of the wind, giving new insight into the complex flow of natural wind around and within raingauges. A new design resulted, and 2 years of field testing have shown that the new gauge has good aerodynamic and evaporative characteristics and minimal outsplash, offering the potential for improved precipitation measurement.

  14. CEOS precipitation constellation

    Science.gov (United States)

    Neeck, Steven P.; Oki, Riko

    2007-10-01

    The outcomes of the 19th Committee on Earth Observing Satellites (CEOS) Plenary held in London in November 2005, recognized that the CEOS Implementation Plan for Space-Based Observations for Global Earth Observation System of Systems (GEOSS) should: - identify the supply of space-based observations required to satisfy the requirements expressed by the 10-year implementation plan for GEOSS; and - propose an innovative process whereby the many disparate types of Earth observing programs funded by CEOS Member agencies might contribute to the supply of the required observations. The CEOS Task Force charged with drafting the CEOS Implementation Plan for Space-Based Observations for GEOSS focused its early efforts on the creation of a 'new planning process' which would satisfy the various criteria demanded by member space agencies, and which would hopefully encourage a new phase of specificity and focus in the multi-lateral co-operation efforts undertaken by space agencies under the CEOS umbrella - resulting in improved engagement of all CEOS Members and real implementation results. The CEOS Constellations is the title given to this new process, and four pilot studies have been initiated in order to pioneer and test the concept. The Japan Aerospace Exploration Agency (JAXA) and the National Aeronautics and Space Administration (NASA) were selected as the lead agencies for the study of the development of a CEOS Precipitation Constellation with the support of other CEOS space agency and user community participants. The goals, approach, and anticipated outcomes for the study will be discussed.

  15. Antiparallel Dynamic Covalent Chemistries.

    Science.gov (United States)

    Matysiak, Bartosz M; Nowak, Piotr; Cvrtila, Ivica; Pappas, Charalampos G; Liu, Bin; Komáromy, Dávid; Otto, Sijbren

    2017-05-17

    The ability to design reaction networks with high, but addressable complexity is a necessary prerequisite to make advanced functional chemical systems. Dynamic combinatorial chemistry has proven to be a useful tool in achieving complexity, however with some limitations in controlling it. Herein we introduce the concept of antiparallel chemistries, in which the same functional group can be channeled into one of two reversible chemistries depending on a controllable parameter. Such systems allow both for achieving complexity, by combinatorial chemistry, and addressing it, by switching from one chemistry to another by controlling an external parameter. In our design the two antiparallel chemistries are thiol-disulfide exchange and thio-Michael addition, sharing the thiol as the common building block. By means of oxidation and reduction the system can be reversibly switched from predominantly thio-Michael chemistry to predominantly disulfide chemistry, as well as to any intermediate state. Both chemistries operate in water, at room temperature, and at mildly basic pH, which makes them a suitable platform for further development of systems chemistry.

  16. Spatio-temporal variation of element accumulation by Moehringia trinervia in a polluted forest ecosystem (South Poland)

    International Nuclear Information System (INIS)

    Kapusta, Pawel; Szarek-Lukaszewska, Grazyna; Godzik, Barbara

    2006-01-01

    The aim of this study was to identify factors affecting accumulation of elements by Moehringia trinervia (L.) Clairv. in a forest ecosystem impacted by long-term inflow of air pollution. The concentrations of N, S, Ca, K, Mg, Cd, Cu, Fe, Pb and Zn were determined in plants collected in 1999. In addition, Cd, Cu, Pb and Zn content was compared with measurements from 1984. Soil properties and bulk precipitation chemistry were used as explaining variables. The amount of heavy metals accumulated by M. trinervia depended on the magnitude of industrial emissions, but only Cu and Pb concentrations were clearly related to the distance from the pollution sources. The spatial distribution of Fe content was shaped by habitat conditions, whereas the distributions of Cd and Zn content were unexplained. Among the macronutrients, only Mg uptake was affected by environmental properties: it was lower under high concentrations of soil Cd and Zn. - Accumulation of heavy metals (Cd, Cu, Fe, Pb and Zn) by Moehringia trinervia reflects the impact of both pollutant deposition and soil properties

  17. Spatio-temporal variation of element accumulation by Moehringia trinervia in a polluted forest ecosystem (South Poland)

    Energy Technology Data Exchange (ETDEWEB)

    Kapusta, Pawel [Department of Ecosystem Studies, Institute of Environmental Sciences, Jagiellonian University, Gronostajowa 7, 30-387 Cracow (Poland)]. E-mail: pkapusta@comhlan.art.pl; Szarek-Lukaszewska, Grazyna [W. Szafer Institute of Botany, Polish Academy of Sciences, Lubicz 46, 31-512 Cracow (Poland); Godzik, Barbara [W. Szafer Institute of Botany, Polish Academy of Sciences, Lubicz 46, 31-512 Cracow (Poland)

    2006-09-15

    The aim of this study was to identify factors affecting accumulation of elements by Moehringia trinervia (L.) Clairv. in a forest ecosystem impacted by long-term inflow of air pollution. The concentrations of N, S, Ca, K, Mg, Cd, Cu, Fe, Pb and Zn were determined in plants collected in 1999. In addition, Cd, Cu, Pb and Zn content was compared with measurements from 1984. Soil properties and bulk precipitation chemistry were used as explaining variables. The amount of heavy metals accumulated by M. trinervia depended on the magnitude of industrial emissions, but only Cu and Pb concentrations were clearly related to the distance from the pollution sources. The spatial distribution of Fe content was shaped by habitat conditions, whereas the distributions of Cd and Zn content were unexplained. Among the macronutrients, only Mg uptake was affected by environmental properties: it was lower under high concentrations of soil Cd and Zn. - Accumulation of heavy metals (Cd, Cu, Fe, Pb and Zn) by Moehringia trinervia reflects the impact of both pollutant deposition and soil properties.

  18. Precipitation in the Solar System

    Science.gov (United States)

    McIntosh, Gordon

    2007-01-01

    As an astronomy instructor, I am always looking for commonly observed Earthly experiences to help my students and me understand and appreciate similar occurrences elsewhere in the solar system. Recently I wrote a short TPT article on frost. This paper is on the related phenomena of precipitation. Precipitation, so common on most of the Earth's…

  19. Decontaminating soil organic pollutants with manufactured nanoparticles.

    Science.gov (United States)

    Li, Qi; Chen, Xijuan; Zhuang, Jie; Chen, Xin

    2016-06-01

    Organic pollutants in soils might threaten the environmental and human health. Manufactured nanoparticles are capable to reduce this risk efficiently due to their relatively large capacity of sorption and degradation of organic pollutants. Stability, mobility, and reactivity of nanoparticles are prerequisites for their efficacy in soil remediation. On the basis of a brief introduction of these issues, this review provides a comprehensive summary of the application and effectiveness of various types of manufactured nanoparticles for removing organic pollutants from soil. The main categories of nanoparticles include iron (oxides), titanium dioxide, carbonaceous, palladium, and amphiphilic polymeric nanoparticles. Their advantages (e.g., unique properties and high sorption capacity) and disadvantages (e.g., high cost and low recovery) for soil remediation are discussed with respect to the characteristics of organic pollutants. The factors that influence the decontamination effects, such as properties, surfactants, solution chemistry, and soil organic matter, are addressed.

  20. Kinetics of cadmium hydroxide precipitation

    International Nuclear Information System (INIS)

    Patterson, J.W.; Marani, D.; Luo, B.; Swenson, P.

    1987-01-01

    This paper presents some preliminary results on the kinetics of Cd(OH)/sub 2/ precipitation, both in the absence and the presence of citric acid as an inhibiting agent. Batch and continuous stirred tank reactor (CSTR) precipitation studies are performed by mixing equal volumes of NaOH and Cd(NO/sub 3/)/sub 2/ solutions, in order to avoid localized supersaturation conditions. The rate of metal removal from the soluble phase is calculated from the mass balance for the CSTR precipitation tests. In addition, precipitation kinetics are studied in terms of nucleation and crystal growth rates, by means of a particle counter that allows a population balance analysis for the precipitation reactor at steady state conditions

  1. Encoding information into precipitation structures

    International Nuclear Information System (INIS)

    Martens, Kirsten; Bena, Ioana; Droz, Michel; Rácz, Zoltan

    2008-01-01

    Material design at submicron scales would be profoundly affected if the formation of precipitation patterns could be easily controlled. It would allow the direct building of bulk structures, in contrast to traditional techniques which consist of removing material in order to create patterns. Here, we discuss an extension of our recent proposal of using electrical currents to control precipitation bands which emerge in the wake of reaction fronts in A + + B – → C reaction–diffusion processes. Our main result, based on simulating the reaction–diffusion–precipitation equations, is that the dynamics of the charged agents can be guided by an appropriately designed time-dependent electric current so that, in addition to the control of the band spacing, the width of the precipitation bands can also be tuned. This makes straightforward the encoding of information into precipitation patterns and, as an amusing example, we demonstrate the feasibility by showing how to encode a musical rhythm

  2. Coping with Indoor Air Pollution

    Science.gov (United States)

    ... Pollution > Coping with Indoor Air Pollution Font: Outdoor Pollution Indoor Air Pollution Asthma Triggers For Kids and Teachers Coping with Indoor Air Pollution Indoor air pollution is irritating to everyone: But people who ...

  3. Aquatic chemistry of acid deposition

    Energy Technology Data Exchange (ETDEWEB)

    Stumm, W; Sigg, L; Schnoor, J L

    1987-01-01

    The occurrence of acid precipitation in many regions of the Northern hemisphere is a consequnece of human interference in the cycles that unite land, water and atmosphere. The oxidation of carbon, sulfur and nitrogen, resulting mostly from fossil fuel burning, rivals oxidation processes induced by photosynthesis and respiration and disturbs redox conditions in the atmosphere. The paper discusses oxidation-reduction reactions, particularly those involving atmospheric pollutants that are important in the formation of acid precipitation. Topics covered are: a stoichiometric model of acid rain formation; sulfur dioxide and ammonia adsorption; acid neutralizing capacity. The paper concludes that explanations of simple chemical equilibria between gases and water aid our understanding of how acidifying gases become dissolved in cloud water, in droplets of falling rain, or in fog. Rigorous definitions of base- or acid-neutralizing capacities are prerequisites to measuring and interpreting residual acidity in dry and wet deposition and for assessing the disturbance caused by the transfer of acid to terrestrial and aquatic ecosystems. 20 references.

  4. Environmental Pollution: Noise Pollution - Sonic Boom

    Science.gov (United States)

    1977-06-01

    UNCLASSIFIED AD-A041 400 DDC/BIB-77/06 ENVIRONMENTAL POLLUTION NOISE POLLUTION SONIC BOOM A DDC BIBLIOGRAPHY DDC-TAS Cameron Station Alexandria, Va...rn7Sttio 658S-A041 400 4 TITLE xand r.VuhtlVlia) 2 TA i b- 1iblog ra ph y ENVIRONMENTAL POLLUTION : --. Apr-l IM59-Jul, 7NOISE POLLUTION -SONIC BOOM. 1,976...BIBLIOGRAPHY SEARCH CONTROL NO. /2OM09 AD- 769 970 20/1 1/3 DEFENSE UOCUMENTATION CENTER ALEXANDRIA VA ENVIRONMENTAL POLLUTION : NOISE POLLUTION

  5. Tropospheric chemistry research in the U.S.: 1991-1994

    Science.gov (United States)

    Penner, Joyce E.; Atherton, Cynthia S.; Dignon, Jane

    1995-07-01

    The troposphere is chemically complex. Many of the important species in the troposphere are short-lived, with lifetimes less than or of order of a month. Hence, the composition of the troposphere is regionally diverse, leading to regionally diverse chemical processes which control that composition. With the advent of three-dimensional models and regionally-specific estimates of emissions, however, it has become clear that human activity has perturbed the composition of even short-lived species over vast regions of the globe. The list of short-lived species of concern includes the reactive nitrogen oxides, reactive sulfur, ozone, nonmethane hydrocarbons and carbon monoxide. Observations have established that increases in the long-lived species such as carbon dioxide, methane, nitrous oxide, and the chlorofluorocarbons are taking place with important resulting impacts on stratospheric chemistry. Further, there is some indication that carbonyl sulfide (a major precursor to stratospheric aerosols) may have an important anthropogenic source. Growth of pollutants such as these are of concern because they act as greenhouse gases or aerosol precursors (CO2, CH4, O3, N2O, chlorofluorocarbons, carbonyl sufide, reactive sulfur), as agents for depletion of stratospheric ozone (N2O, chlorofluorocarbons), are harmful to vegetation (O3, acids) or act as nutrients (nitrate, sulfate, trace metals). The chemical interactions are important to understand, because the build up of pollutants depends not only on the rates of their release into the troposphere but on their rate of removal in the troposphere. Removal rates depend on processes which determine the rate of oxidation of the component (which for most species proceeds mainly by reaction with the hydroxyl radical) or through precipitation scavenging or dissolution in the ocean (which requires that the pollutant or its oxidation product(s) be soluble in water).

  6. Chemistry and sustainable environment (abstract)

    International Nuclear Information System (INIS)

    Hussain, M.

    2011-01-01

    Chemistry is one of the oldest branches of science; the human beings had ever come across. It has consistently contributed towards meeting the human needs from the dawn of civilization. However, its role has multiplied since the inception of industrial revolution. Although anthropogenic activities have made the human life comfortable and even luxurious yet their impacts on the physical, biological and socio-economic environments had been destructive. Numerous kinds of chemicals have engulfed us and our environment. Modern chemistry has leading role in sculpting the present as well as future of human lifestyle. It is serving the man and other biodiversity by providing countless products in every sphere of life. At the same time it is playing villain role in the destruction of environment at an alarming rate. Today the world is confronted with heinous environmental issues hitherto unknown to the living beings mostly triggered by chemicals. Thousands of chemicals are used in industrial products, agricultural chemicals, persistent organic pollutants, freezers, pharmaceuticals, chemical and radiological warfare, construction industry, synthetic materials, electrical goods, medical gadgets etc. Some natural sources of chemicals are acid rains, volcanic eruptions, eutrophication and photochemical smog. The fact of matter is that chemicals are being consistently added into atmosphere, biosphere and lithosphere. For the sustainable environment it is imperative that the chemicals must not be added into human environment beyond its carrying capacity. It is responsibility of chemists to introduce environmentally benign and biodegradable chemicals. All types of chemistry need to be green and environment friendly. The scientists and engineers should develop chemicals and technologies which do not harm the living creatures during any stage of their life-cycle. (author)

  7. Fine-scale precipitation and mechanical properties of thin slab processed titanium-niobium bearing high strength steels

    Energy Technology Data Exchange (ETDEWEB)

    Jia, Z. [Center for Structural and Functional Materials, University of Louisiana at Lafayette, P.O. Box 44130, Lafayette, LA 70503 (United States); Misra, R.D.K., E-mail: dmisra@louisiana.edu [Center for Structural and Functional Materials, University of Louisiana at Lafayette, P.O. Box 44130, Lafayette, LA 70503 (United States); O' Malley, R. [Nucor Steel Decatur, LLC, 4301 Iverson Blvd., Trinity, AL 35673 (United States); Jansto, S.J. [CBMM-Reference Metals Company, 1000 Old Pond Road, Bridgeville, PA 15017 (United States)

    2011-08-25

    Highlights: {yields} Precipitation and mechanical behavior of Ti-Nb and Ti-Nb-Mo-V steels were elucidated. {yields} Distribution of precipitates was analyzed with microscopy and diffraction pattern. {yields} During austenite-ferrite transformation, interface precipitation of NbC was observed. {yields} Epitaxial precipitation of NbC on TiC surface results in mixed precipitates Ti(Nb)C. - Abstract: We describe here the precipitation behavior and mechanical properties of 560 MPa Ti-Nb and 770 MPa Ti-Nb-Mo-V steels. The precipitation characteristics were analyzed in terms of chemistry and size distribution of precipitates, with particular focus on the crystallography of precipitates through an analysis of electron diffraction patterns. In addition to pure carbides (NbC, TiC, Mo{sub 2}C, and VC), Nb containing titanium-rich carbides were also observed. These precipitates were of a size range of 4-20 nm. The mechanism of formation of these Ti-rich niobium containing carbides is postulated to involve epitaxial nucleation of NbC on previously precipitated TiC. Interface precipitation of NbC was an interesting observation in compact strip processing which is characterized by an orientation relationship of [0 0 1]{sub NbC}//[0 0 1]{sub {alpha}-Fe}, implying that the precipitation of NbC occurred during austenite-ferrite transformation.

  8. Fine-scale precipitation and mechanical properties of thin slab processed titanium-niobium bearing high strength steels

    International Nuclear Information System (INIS)

    Jia, Z.; Misra, R.D.K.; O'Malley, R.; Jansto, S.J.

    2011-01-01

    Highlights: → Precipitation and mechanical behavior of Ti-Nb and Ti-Nb-Mo-V steels were elucidated. → Distribution of precipitates was analyzed with microscopy and diffraction pattern. → During austenite-ferrite transformation, interface precipitation of NbC was observed. → Epitaxial precipitation of NbC on TiC surface results in mixed precipitates Ti(Nb)C. - Abstract: We describe here the precipitation behavior and mechanical properties of 560 MPa Ti-Nb and 770 MPa Ti-Nb-Mo-V steels. The precipitation characteristics were analyzed in terms of chemistry and size distribution of precipitates, with particular focus on the crystallography of precipitates through an analysis of electron diffraction patterns. In addition to pure carbides (NbC, TiC, Mo 2 C, and VC), Nb containing titanium-rich carbides were also observed. These precipitates were of a size range of 4-20 nm. The mechanism of formation of these Ti-rich niobium containing carbides is postulated to involve epitaxial nucleation of NbC on previously precipitated TiC. Interface precipitation of NbC was an interesting observation in compact strip processing which is characterized by an orientation relationship of [0 0 1] NbC //[0 0 1] α-Fe , implying that the precipitation of NbC occurred during austenite-ferrite transformation.

  9. Atmospheric chemistry and climate

    OpenAIRE

    Satheesh, SK

    2012-01-01

    Atmospheric chemistry is a branch of atmospheric science where major focus is the composition of the Earth's atmosphere. Knowledge of atmospheric composition is essential due to its interaction with (solar and terrestrial) radiation and interactions of atmospheric species (gaseous and particulate matter) with living organisms. Since atmospheric chemistry covers a vast range of topics, in this article the focus is on the chemistry of atmospheric aerosols with special emphasis on the Indian reg...

  10. Polymer chemistry (revised edition)

    International Nuclear Information System (INIS)

    Kim, Jae Mum

    1987-02-01

    This book deals with polymer chemistry, which is divided into fourteen chapters. The contents of this book are development of polymer chemistry, conception of polymer, measurement of polymer chemistry, conception of polymer, measurement of polymer, molecule structure of polymer, thermal prosperities of solid polymer, basic theory of polymerization, radical polymerization, ion polymerization, radical polymerization, copolymerization, polymerization by step-reaction, polymer reaction, crown polymer and inorganic polymer on classification and process of creation such as polymeric sulfur and carbon fiber.

  11. Chemistry of the elements

    International Nuclear Information System (INIS)

    Greenwood, N.N.; Earnshaw, A.

    1984-01-01

    This textbook presents an account of the chemistry of the elements for both undergraduate and postgraduate students. It covers not only the 'inorganic' chemistry of the elements, but also analytical, theoretical, industrial, organometallic;, bio-inorganic and other areas of chemistry which apply. The following elements of special nuclear interest are included: Rb, Cs, Fr, Sr, Ba, Ra, Po, At, Rn, Sc, Y, Zr, Hf, V, Nb, Ta, Mo, Tc, Ru, the Lanthanide Elements, the Actinide Elements. (U.K.)

  12. Characterization of rainwater chemical composition after a Southeast Asia haze event: insight of transboundary pollutant transport during the northeast monsoon.

    Science.gov (United States)

    Nadzir, Mohd Shahrul Mohd; Lin, Chin Yik; Khan, Md Firoz; Latif, Mohd Talib; Dominick, Doreena; Hamid, Haris Hafizal Abdul; Mohamad, Noorlin; Maulud, Khairul Nizam Abdul; Wahab, Muhammad Ikram Abdul; Kamaludin, Nurul Farahana; Lazim, Mohamad Azwani Shah Mat

    2017-06-01

    Open biomass burning in Peninsula Malaysia, Sumatra, and parts of the Indochinese region is a major source of transboundary haze pollution in the Southeast Asia. To study the influence of haze on rainwater chemistry, a short-term investigation was carried out during the occurrence of a severe haze episode from March to April 2014. Rainwater samples were collected after a prolonged drought and analyzed for heavy metals and major ion concentrations using inductively coupled plasma mass spectroscopy (ICP-MS) and ion chromatography (IC), respectively. The chemical composition and morphology of the solid particulates suspended in rainwater were examined using a scanning electron microscope coupled with energy-dispersive X-ray spectroscopy (SEM-EDS). The dataset was further interpreted using enrichment factors (EF), statistical analysis, and a back trajectory (BT) model to find the possible sources of the particulates and pollutants. The results show a drop in rainwater pH from near neutral (pH 6.54) to acidic (precipitation process was relatively lower compared to the mineral components. Zinc, nitrate, and calcium, which were the predominant elements in the first rainwater samples. Besides, the results of the SEM-EDS indicated that the zinc was possibly originated from anthropogenic activities which are consistent with the results obtained from EF. The BT model showed that pollutants transported from the mainland of Indo-China and the marine region in the South China Sea were responsible for the high pollution event in the study area. These findings can be useful in identifying contributions of pollutants from single or multiple sources in rainwater samples during haze episodes.

  13. From trace chemistry to single atom chemistry

    International Nuclear Information System (INIS)

    Adloff, J.P.

    1993-01-01

    Hot atom chemistry in the vast majority of experimental works deals with the trace amount of radioactive matters. Accordingly, the concept of trace chemistry is at the heart of hot atom chemistry. Some aspects of the chemistry at trace scale and at subtrace scale are presented together with the related problems of speciation and the complication which may arise due to the formation of radio colloids. The examples of 127 I(n,γ) 128 I and 132 Te (β - ) 132 I are shown, and the method based on radioactivity was used. The procedure of separating the elements in pitchblende is shown as the example of the chemistry of traces. 13 27 Al+ 2 4 He→ 0 1 n+ 15 30 P and 15 30 P→ 14 30 Si+e + +V are shown, and how to recognize the presence of radioactive colloids is explained. The formation of radiocolloids is by the sorption of a trace radioelement on pre-existing colloidal impurity or the self-condensation of monomeric species. The temporal parameters of the nature of reactions at trace concentration are listed. The examples of Class A and Class B reactions are shown. The kinetics of reactions at trace level, radon concentration, anthropogenic Pu and natural Pu in environment, the behavior of Pu atoms and so on are described. (K.I.)

  14. Research for the advancement of green chemistry practice: Studies in atmospheric and educational chemistry

    Science.gov (United States)

    Cullipher, Steven Gene

    Green chemistry is a philosophy of chemistry that emphasizes a decreasing dependence on limited non-renewable resources and an increasing focus on preventing pollution byproducts of the chemical industry. In short, it is the discipline of chemistry practiced through the lens of environmental stewardship. In an effort to advance the practice of green chemistry, three studies will be described that have ramifications for the practice. The first study examines the atmospheric oxidation of a hydrofluorinated ether, a third-generation CFC replacement compound with primarily unknown atmospheric degradation products. Determination of these products has the potential to impact decisions on refrigerant usage in the future. The second study examines chemistry students' development of understanding benefits-costs-risks analysis when presented with two real-world scenarios: refrigerant choice and fuel choice. By studying how benefits-costs-risks thinking develops, curricular materials and instructional approaches can be designed to better foster the development of an ability that is both necessary for green chemists and important in daily decision-making for non-chemists. The final study uses eye tracking technology to examine students' abilities to interpret molecular properties from structural information in the context of global warming. Such abilities are fundamental if chemists are to appropriately assess risks and hazards of chemistry practice.

  15. Stream water chemistry in watersheds receiving different atmospheric inputs of H+, NH4+, NO3-, and SO42-1

    Science.gov (United States)

    Stottlemyer, R.

    1997-01-01

    Weekly precipitation and stream water samples were collected from small watersheds in Denali National Park, Alaska, the Fraser Experimental Forest, Colorado, Isle Royale National Park, Michigan, and the Calumet watershed on the south shore of Lake Superior, Michigan. The objective was to determine if stream water chemistry at the mouth and upstream stations reflected precipitation chemistry across a range of atmospheric inputs of H+, NH4+, NO3-, and SO42-. Volume-weighted precipitation H+, NH4+, NO3-, and SO42- concentrations varied 4 to 8 fold with concentrations highest at Calumet and lowest in Denali. Stream water chemistry varied among sites, but did not reflect precipitation chemistry. The Denali watershed, Rock Creek, had the lowest precipitation NO3- and SO42- concentrations, but the highest stream water NO3and SO42- concentrations. Among sites, the ratio of mean monthly upstream NO3- concentration to precipitation NO3- concentration declined (p 90 percent inputs) across inputs ranging from 0.12 to > 6 kg N ha-1 y-1. Factors possibly accounting for the weak or non-existent signal between stream water and precipitation ion concentrations include rapid modification of meltwater and precipitation chemistry by soil processes, and the presence of unfrozen soils which permits winter mineralization and nitrification to occur.

  16. Advances in quantum chemistry

    CERN Document Server

    Sabin, John R

    2013-01-01

    Advances in Quantum Chemistry presents surveys of current topics in this rapidly developing field that has emerged at the cross section of the historically established areas of mathematics, physics, chemistry, and biology. It features detailed reviews written by leading international researchers. This volume focuses on the theory of heavy ion physics in medicine.Advances in Quantum Chemistry presents surveys of current topics in this rapidly developing field that has emerged at the cross section of the historically established areas of mathematics, physics, chemistry, and biology. It features

  17. Canopy Chemistry (OTTER)

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: Canopy characteristics: leaf chemistry, specific leaf area, LAI, PAR, IPAR, NPP, standing biomass--see also: Meteorology (OTTER) for associated...

  18. USSR Report, Chemistry

    National Research Council Canada - National Science Library

    1986-01-01

    This USSR Report on Chemistry contains articles on Aerosols, Adsorption, Biochemistry, Catalysis, Chemical Industry, Coal Gasification, Electrochemistry, Explosives and Explosions, Fertilizers, Food...

  19. Elements of environmental chemistry

    National Research Council Canada - National Science Library

    Hites, R. A; Raff, Jonathan D

    2012-01-01

    ... more. Extensively revised, updated, and expanded, this second edition includes new chapters on atmospheric chemistry, climate change, and polychlorinated biphenyls and dioxins, and brominated flame retardants...

  20. Green Chemistry Pedagogy

    Science.gov (United States)

    Kolopajlo, Larry

    2017-02-01

    This chapter attempts to show how the practice of chemistry teaching and learning is enriched by the incorporation of green chemistry (GC) into lectures and labs. To support this viewpoint, evidence from a wide range of published papers serve as a cogent argument that GC attracts and engages both science and nonscience students, enhances chemistry content knowledge, and improves the image of the field, while preparing the world for a sustainable future. Published pedagogy associated with green and sustainable chemistry is critically reviewed and discussed.

  1. DOE fundamentals handbook: Chemistry

    International Nuclear Information System (INIS)

    1993-01-01

    This handbook was developed to assist nuclear facility operating contractors in providing operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of chemistry. This volume contains the following modules: reactor water chemistry (effects of radiation on water chemistry, chemistry parameters), principles of water treatment (purpose; treatment processes [ion exchange]; dissolved gases, suspended solids, and pH control; water purity), and hazards of chemicals and gases (corrosives [acids, alkalies], toxic compounds, compressed gases, flammable/combustible liquids)

  2. Mesoscale storm and dry period parameters from hourly precipitation data: program documentation

    Energy Technology Data Exchange (ETDEWEB)

    Thorp, J.M.

    1984-09-01

    Wet deposition of airborne chemical pollutants occurs primarily from precipitation. Precipitation rate, amount, duration, and location are important meteorological factors to be considered when attempting to understand the relationship of precipitation to pollutant deposition. The Pacific Northwest Laboratory (PNL) has conducted studies and experiments in numerous locations to collect data that can be incorporated into theories and models that attempt to describe the complex relationship between precipitation occurrence and chemical wet desposition. Model development often requires the use of average rather than random condition as input. To provide mean values of storm parameters, the task, Climatological Analysis of Mesoscale Storms, was created as a facet of the Environmental Protection Agency's related-service project, Precipitation Scavenging Module Development. Within this task computer programs have been developed at PNL which incorporate hourly precipitation data from National Weather Service stations to calculate mean values and frequency distributions of precipitation periods and of the interspersed dry periods. These programs have been written with a degree of flexibiity that will allow user modification for applications to different, but similar, analyses. This report describes in detail the rationale and operation of the two computer programs which produce the tables of average and frequency distributions of storm and dry period parameters from the precipitation data. A listing of the programs and examples of the generated output are included in the appendices. 3 references, 3 figures, 6 tables.

  3. The significant reduction of precipitation in Southern China during the Chinese Spring Festival

    Science.gov (United States)

    Zhang, J.; Gong, D.

    2016-12-01

    Long-term observational data from 2001 to 2012 over 339 stations were used to analyze the precipitation in southern China during the Chinese Spring Festival (CSF). It reveals both the precipitation frequency and precipitation intensity have a significant reduction around CSF holiday. From the second day to the sixth day after the Lunar New Year's Day, the daily mean precipitation frequency anomaly is -9%. At the same time, more than 90% stations in the study area have negative anomalies. The precipitation intensity has a continuous reduction from day 2 to day 4, which is up to 2mm in day 3. Other relevant variables, such as relative humidity and sunshine duration, have corresponding results to the precipitation's reduction during CSF. Atmospheric water vapor field's change leads to the reduction phenomenon. We analyzed the circulation configuration using the ERA-interim reanalysis data. It shows the anomalous north wind decrease the vapor and further affects the precipitation during the CSF period. The pollutants' concentration decreased around CSF, which may influence the meteorological field and lead to the anomalous north wind. Based on the S2S (sub-seasonal to seasonal prediction project) data, we calculated the circulation forecast difference to CSF period between clean days and polluted days. The result proves the north wind's existence and suggests that the aerosol decrease because of human activity may be partly responsible for the precipitation reduction during CSF.

  4. Stability and precipitation of diverse nanoparticles

    Science.gov (United States)

    Desai, Chintal

    Nanotechnology is a rapidly growing industry that is exploiting the novel characteristics of materials manufactured at the nanoscale. Carbon based nanomaterials such as Carbon Nanotubes (CNTs) and Detonation Nanodiamond (DND) possess unique properties and find a wide range of industrial applications. With the advent of mass production of such materials, there is a possibility of contamination of water resources. Depending on the surface properties and structures, they might aggregate and settle down, or be dispersed and transported by the water. Therefore, there is a need to develop an understanding of the fate of such materials in aqueous media. The understanding and effect of solution chemistry is a key to predicting their deposition, transport, reactivity, and bioavailability in aquatic environments. The colloidal behavior of organic dispersed CNTs and water dispersed DNDs is investigated. The aggregation behavior of these two colloidal systems is quite different from that of hydrophilic, water soluble functionalized CNTs (F-CNTs). The values of the Fuchs stability ratio or the critical coagulant concentration are determined experimentally using time-resolved dynamic light scattering and are used to predict the stability of such systems. It is found that the aggregation behavior of the organic dispersed, antisolvent precipitated system does not follow the conventional Derjaguin--Landau--Verwey-- Overbeek (DLVO) theory. But they stabilize in the long term, which is attributed to the supersaturation generated by different solubility of a solute in the solvent/antisolvent. Based on particle size distribution, zeta potential as well as the aggregation kinetics, the water dispersed DNDs are found to be relatively stable in aqueous solutions, but aggregate rapidly in presence of mono and divalent salts. Also, the formation of carboxylic groups on the DND surface does not alter colloidal behavior as dramatically as it does for other nanocarbons especially carbon

  5. Indoor Air Pollution

    Science.gov (United States)

    We usually think of air pollution as being outdoors, but the air in your house or office could also be polluted. Sources of indoor pollution include Mold and pollen Tobacco smoke Household products ...

  6. Precipitation scavenging of aerosol particles at a rural site in the Czech Republic

    Science.gov (United States)

    Zikova, Nadezda; Zdimal, Vladimir

    2017-04-01

    concentrations of AA particles smaller than 80 nm are lower than they are during periods without any phenomenon recorded. Also during liquid precipitation, PNSD are lower when compared to non-event periods, suggesting an effective AA deposition. Precipitation containing frozen hydrometeors behaves differently from liquid precipitation. Concentrations of AA particles larger than 200 nm during precipitation containing solid particles do not differ from non-event cases, suggesting insignificant scavenging. The results of the observed size dependent changes in AA concentrations and PNSD could be used to assess the expected changes in atmosphere during transport and scavenging of AA not only during experimental campaigns, but during modelling as well. This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No. 654109. Andronache at al. 2006. Atmos. Chem. Phys. 6, 4739-54. Chate at al. 2011. Atmos. Res. 99(3-4), 528-536. Collett at al. 2008. Atmos. Res. 87(3-4), 232-241. Laakso et al. 2003. Atmos. Environ. 37(25), 3605-3613. Ladino at al. 2011. J. Atmos. Sci. 68(9), 1853-1864. Seinfeld and Pandis. 2012. Atmospheric Chemistry and Physics: From Air Pollution to Climate Change, Wiley.

  7. On the Precipitation and Precipitation Change in Alaska

    Directory of Open Access Journals (Sweden)

    Gerd Wendler

    2017-12-01

    Full Text Available Alaska observes very large differences in precipitation throughout the state; southeast Alaska experiences consistently wet conditions, while northern Arctic Alaska observes very dry conditions. The maximum mean annual precipitation of 5727 mm is observed in the southeastern panhandle at Little Port Arthur, while the minimum of 92 mm occurs on the North Slope at Kuparuk. Besides explaining these large differences due to geographic and orographic location, we discuss the changes in precipitation with time. Analyzing the 18 first-order National Weather Service stations, we found that the total average precipitation in the state increased by 17% over the last 67 years. The observed changes in precipitation are furthermore discussed as a function of the observed temperature increase of 2.1 °C, the mean temperature change of the 18 stations over the same period. This observed warming of Alaska is about three times the magnitude of the mean global warming and allows the air to hold more water vapor. Furthermore, we discuss the effect of the Pacific Decadal Oscillation (PDO, which has a strong influence on both the temperature and precipitation in Alaska.

  8. ARM Cloud-Aerosol-Precipitation Experiment (ACAPEX) Field Campaign Report

    Energy Technology Data Exchange (ETDEWEB)

    Leung, L Ruby [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-03-01

    The U.S. Department of Energy (DOE)’s Atmospheric Radiation Measurement (ARM) Climate Research Facility’s ARM Cloud-Aerosol-Precipitation Experiment (ACAPEX) field campaign contributes to CalWater 2015, a multi-agency field campaign that aims to improve understanding of atmospheric rivers and aerosol sources and transport that influence cloud and precipitation processes. The ultimate goal is to reduce uncertainties in weather predictions and climate projections of droughts and floods in California. With the DOE G-1 aircraft and ARM Mobile Facility 2 (AMF2) well equipped for making aerosol and cloud measurements, ACAPEX focuses specifically on understanding how aerosols from local pollution and long-range transport affect the amount and phase of precipitation associated with atmospheric rivers. ACAPEX took place between January 12, 2015 and March 8, 2015 as part of CalWater 2015, which included four aircraft (DOE G-1, National Oceanic and Atmospheric Administration [NOAA] G-IV and P-3, and National Aeronautics and Space Administration [NASA] ER-2), the NOAA research ship Ron Brown, carrying onboard the AMF2, National Science Foundation (NSF)-sponsored aerosol and precipitation measurements at Bodega Bay, and the California Department of Water Resources extreme precipitation network.

  9. Annual report 1989 Chemistry Department

    International Nuclear Information System (INIS)

    Funck, J.; Neve Larsen, Aa.; Larsen, E.; Nielsen, O.J.

    1990-03-01

    This report contains a brief survey of the main activities in the Chemistry Department. The names and abstracts of all articles and reports published and lectures given in 1989 are presented. The facilities and equipment are mentioned briefly. The activities are divided into the following groups: radioisotope chemistry, analytical- and organic chemistry, environmental chemistry, polymer chemistry, chemical reactivity, mineral processing, and general. (author)

  10. Annual report 1988 Chemistry Department

    International Nuclear Information System (INIS)

    Funck, J.; Neve Larsen, Aa.; Larsen, E.; Nielsen, O.J.

    1989-05-01

    This report contains a brief survey of the main activities in the Chemistry Department. The names and abstracts of all articles and reports published and lectures given in 1988 are presented. The facilities and equipment are mentioned briefly. The activities are divided into the following groups: radioisotope chemistry, analytical- and organic chemistry, environmental chemistry, polymer chemistry, chemical reactivity, mineral processing, and general. (author)

  11. Annual report 1986 chemistry department

    International Nuclear Information System (INIS)

    Funck, J.; Larsen, E.; Nielsen, O.J.

    1987-03-01

    This report contains a brief survey of the main activities in the Chemistry Department. All articles and reports published and lectures given in 1986 are presented. The facilities and equipment are mentioned briefly. The activities are divided into the following groups: radioisotope chemistry, analytical- and organic chemistry, environmental chemistry, polymer chemistry, radical chemistral, mineral processing, and general. (author)

  12. On the application of the classic Kessler and Berry schemes in Large Eddy Simulation models with a particular emphasis on cloud autoconversion, the onset time of precipitation and droplet evaporation

    Directory of Open Access Journals (Sweden)

    S. Ghosh

    Full Text Available Many Large Eddy Simulation (LES models use the classic Kessler parameterisation either as it is or in a modified form to model the process of cloud water autoconversion into precipitation. The Kessler scheme, being linear, is particularly useful and is computationally straightforward to implement. However, a major limitation with this scheme lies in its inability to predict different autoconversion rates for maritime and continental clouds. In contrast, the Berry formulation overcomes this difficulty, although it is cubic. Due to their different forms, it is difficult to match the two solutions to each other. In this paper we single out the processes of cloud conversion and accretion operating in a deep model cloud and neglect the advection terms for simplicity. This facilitates exact analytical integration and we are able to derive new expressions for the time of onset of precipitation using both the Kessler and Berry formulations. We then discuss the conditions when the two schemes are equivalent. Finally, we also critically examine the process of droplet evaporation within the framework of the classic Kessler scheme. We improve the existing parameterisation with an accurate estimation of the diffusional mass transport of water vapour. We then demonstrate the overall robustness of our calculations by comparing our results with the experimental observations of Beard and Pruppacher, and find excellent agreement.

    Key words. Atmospheric composition and structure · Cloud physics and chemistry · Pollution · Meteorology and atmospheric dynamics · Precipitation

  13. On the application of the classic Kessler and Berry schemes in Large Eddy Simulation models with a particular emphasis on cloud autoconversion, the onset time of precipitation and droplet evaporation

    Directory of Open Access Journals (Sweden)

    S. Ghosh

    1998-05-01

    Full Text Available Many Large Eddy Simulation (LES models use the classic Kessler parameterisation either as it is or in a modified form to model the process of cloud water autoconversion into precipitation. The Kessler scheme, being linear, is particularly useful and is computationally straightforward to implement. However, a major limitation with this scheme lies in its inability to predict different autoconversion rates for maritime and continental clouds. In contrast, the Berry formulation overcomes this difficulty, although it is cubic. Due to their different forms, it is difficult to match the two solutions to each other. In this paper we single out the processes of cloud conversion and accretion operating in a deep model cloud and neglect the advection terms for simplicity. This facilitates exact analytical integration and we are able to derive new expressions for the time of onset of precipitation using both the Kessler and Berry formulations. We then discuss the conditions when the two schemes are equivalent. Finally, we also critically examine the process of droplet evaporation within the framework of the classic Kessler scheme. We improve the existing parameterisation with an accurate estimation of the diffusional mass transport of water vapour. We then demonstrate the overall robustness of our calculations by comparing our results with the experimental observations of Beard and Pruppacher, and find excellent agreement.Key words. Atmospheric composition and structure · Cloud physics and chemistry · Pollution · Meteorology and atmospheric dynamics · Precipitation

  14. Mainz University, Institute of Nuclear Chemistry. Annual report 1993

    International Nuclear Information System (INIS)

    Denschlag, H.O.

    1994-03-01

    The report presents the results achieved by the Institute's five working groups in the following fields: Development of chemical separation processes, chemistry of ultraheavy elements; Developments in instrumentation; Nuclear fission and heavy ion reactions; Nuclear astrophysics, decay characteristics, structure of atoms and nuclei; Environmental pollution analysis. (orig./EF) [de

  15. Chemistry for protection of the environment, Eight international conference: Proceedings

    International Nuclear Information System (INIS)

    Lacy, W.J.; Pawlowski, L.; Dlugosz, J.J.

    1991-01-01

    This report presents research programs from the International Conference on the Chemistry For Protection of the Environment. Topics covered include environmental transport, waste minimization, pollution control and prevention, waste management, soil remediation, and health concerns associated with environmental contamination. Individual projects are processed separately for the data bases

  16. Interannual Variations in Aerosol Sources and Their Impact on Orographic Precipitation over California's Central Sierra Nevada

    Science.gov (United States)

    Creamean, J.; Ault, A. P.; White, A. B.; Neiman, P. J.; Minnis, P.; Prather, K. A.

    2014-12-01

    Aerosols that serve as cloud condensation nuclei (CCN) and ice nuclei (IN) have the potential to profoundly influence precipitation processes. Furthermore, changes in orographic precipitation have broad implications for reservoir storage and flood risks. As part of the CalWater I field campaign (2009-2011), the impacts of aerosol sources on precipitation were investigated in the California Sierra Nevada Mountains. In 2009, the precipitation collected on the ground was influenced by both local biomass burning and long-range transported dust and biological particles, while in 2010, by mostly local sources of biomass burning and pollution, and in 2011 by mostly long-range transport of dust and biological particles from distant sources. Although vast differences in the sources of residues were observed from year-to-year, dust and biological residues were omnipresent (on average, 55% of the total residues combined) and were associated with storms consisting of deep convective cloud systems and larger quantities of precipitation initiated in the ice phase. Further, biological residues were dominant during storms with relatively warm cloud temperatures (up to -15°C), suggesting biological components were more efficient IN than mineral dust. On the other hand, when precipitation quantities were lower, local biomass burning and pollution residues were observed (on average 31% and 9%, respectively), suggesting these residues potentially served as CCN at the base of shallow cloud systems and that lower level polluted clouds of storm systems produced less precipitation than non-polluted (i.e., marine) clouds. The direct connection of the sources of aerosols within clouds and precipitation type and quantity can be used in models to better assess how local emissions versus long-range transported dust and biological aerosols play a role in impacting regional weather and climate, ultimately with the goal of more accurate predictive weather forecast models and water resource

  17. USCG Vessel Pollution

    Data.gov (United States)

    Department of Homeland Security — The Marine Casualty and Pollution Data files provide details about marine casualty and pollution incidents investigated by Coast Guard Offices throughout the United...

  18. USCG Facility Pollution

    Data.gov (United States)

    Department of Homeland Security — The Marine Casualty and Pollution Data files provide details about marine casualty and pollution incidents investigated by Coast Guard Offices throughout the United...

  19. Titanocene sulfide chemistry

    Czech Academy of Sciences Publication Activity Database

    Horáček, Michal

    2016-01-01

    Roč. 314, MAY 2016 (2016), s. 83-102 ISSN 0010-8545 R&D Projects: GA ČR(CZ) GAP207/12/2368 Institutional support: RVO:61388955 Keywords : titanocene sulfide chemistry * photolysis * titanocene hydrosulfides Ti-(SH)n Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 13.324, year: 2016

  20. A green chemistry approach

    Indian Academy of Sciences (India)

    Administrator

    One-pot synthesis of quinaldine derivatives by using microwave irradiation without any solvent – A green chemistry approach. JAVAD SAFARI*, SAYED HOSSEIN BANITABA and SEPEHR SADEGH SAMIEI. Department of Chemistry, The Faculty of sciences, University of Kashan, Kashan,. P.O. Box 87317-51167, I.R. Iran.

  1. Chemistry of americium

    Energy Technology Data Exchange (ETDEWEB)

    Schulz, W.W.

    1976-01-01

    Essential features of the descriptive chemistry of americium are reviewed. Chapter titles are: discovery, atomic and nuclear properties, collateral reading, production and uses, chemistry in aqueous solution, metal, alloys, and compounds, and, recovery, separation, purification. Author and subject indexes are included. (JCB)

  2. Movies in Chemistry Education

    Science.gov (United States)

    Pekdag, Bulent; Le Marechal, Jean-Francois

    2010-01-01

    This article reviews numerous studies on chemistry movies. Movies, or moving pictures, are important elements of multimedia and signify a privileged or motivating means of presenting knowledge. Studies on chemistry movies show that the first movie productions in this field were devoted to university lectures or documentaries. Shorter movies were…

  3. WATER CHEMISTRY ASSESSMENT METHODS

    Science.gov (United States)

    This section summarizes and evaluates the surfce water column chemistry assessment methods for USEPA/EMAP-SW, USGS-NAQA, USEPA-RBP, Oho EPA, and MDNR-MBSS. The basic objective of surface water column chemistry assessment is to characterize surface water quality by measuring a sui...

  4. The Breath of Chemistry

    DEFF Research Database (Denmark)

    Josephsen, Jens

    The present preliminary text is a short thematic presentation in biological inorganic chemistry meant to illustrate general and inorganic (especially coordination) chemistry in biochemistry. The emphasis is on molecular models to explain features of the complicated mechanisms essential to breathing...

  5. Exercises in Computational Chemistry

    DEFF Research Database (Denmark)

    Spanget-Larsen, Jens

    2016-01-01

    A selection of HyperChem© PC-exercises in computational chemistry. Answers to most questions are appended (Roskilde University 2014-16).......A selection of HyperChem© PC-exercises in computational chemistry. Answers to most questions are appended (Roskilde University 2014-16)....

  6. Chemistry and Biology

    Science.gov (United States)

    Wigston, David L.

    1970-01-01

    Discusses the relationship between chemisty and biology in the science curriculum. Points out the differences in perception of the disciplines, which the physical scientists favoring reductionism. Suggests that biology departments offer a special course for chemistry students, just as the chemistry departments have done for biology students.…

  7. Precipitation of lithium in germanium

    International Nuclear Information System (INIS)

    Masaik, M.; Furgolle, B.

    1969-01-01

    The precipitation of Lithium in Germanium was studied. Taking account of the interactions Ga LI, LiO, we calculated the oxygen content in germanium samples from the resistivity measurements. (authors)

  8. Environmental Radioactivity, Temperature, and Precipitation.

    Science.gov (United States)

    Riland, Carson A.

    1996-01-01

    Reports that environmental radioactivity levels vary with temperature and precipitation and these effects are due to radon. Discusses the measurement of this environmental radioactivity and the theory behind it. (JRH)

  9. Aluminum precipitation from Hanford DSSF

    International Nuclear Information System (INIS)

    Borgen, D.; Frazier, P.; Staton, G.

    1994-01-01

    A series of pilot scale tests using simulated Double Shell Slurry Feed (DSSF) showed that well-settled aluminum precipitate can be produced in Hanford double shell tank (DST) high level waste by slow neutralization with carbon dioxide. This pretreatment could provide an early grout feed and free tank space, as well as facilitate downstream processes such as ion exchange by providing a less caustic feed. A total of eight test runs were completed using a 10-ft tall 3-in i.d. glass column. The 10-ft height corresponds to about one third of the vertical height of a DST, hence providing a reasonable basis for extrapolating the observed precipitate settling and compaction to the actual waste tank environment. Four runs (three with a simplified simulant and one with a chemically complete simulant) produced well settled precipitates averaging 1.5 to 2 feet high. Aluminum gel rather than settled precipitate resulted from one test where neutralization was too rapid

  10. Hourly and Daily Precipitation Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Precipitation reports submitted on many form types, including tabular and autographic charts. Reports are almost exclusively from the US Cooperative Observer Network.

  11. Evaluation of Coupled Precipitator Two

    International Nuclear Information System (INIS)

    Stone, M.E.

    1999-01-01

    The offline testing of the Coupled Precipitator Two (CP-2) has been completed. The tests were conducted and are documented. The tests were conducted at an offline test rack near the Drain Tube Test Stand facility in 672-T

  12. Transuranic Computational Chemistry.

    Science.gov (United States)

    Kaltsoyannis, Nikolas

    2018-02-26

    Recent developments in the chemistry of the transuranic elements are surveyed, with particular emphasis on computational contributions. Examples are drawn from molecular coordination and organometallic chemistry, and from the study of extended solid systems. The role of the metal valence orbitals in covalent bonding is a particular focus, especially the consequences of the stabilization of the 5f orbitals as the actinide series is traversed. The fledgling chemistry of transuranic elements in the +II oxidation state is highlighted. Throughout, the symbiotic interplay of experimental and computational studies is emphasized; the extraordinary challenges of experimental transuranic chemistry afford computational chemistry a particularly valuable role at the frontier of the periodic table. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Third Chemistry Conference on Recent Trends in Chemistry

    International Nuclear Information System (INIS)

    Saeed, M.M.; Wheed, S.

    2011-01-01

    The third chemistry conference 2011 on recent trends in chemistry was held from October 17-19, 2001 at Islamabad, Pakistan. More than 65 papers and oral presentation. The scope of the conference was wide open and provides and opportunity for participation of broad spectrum of chemists. This forum provided a platform for the dissemination of the latest research followed by discussion pertaining to new trends in chemistry. This con fence covered different aspects of subjects including analytical chemistry, environmental chemistry, polymer chemistry, industrial chemistry, biochemistry and nano chemistry etc. (A.B.)

  14. Korean Kimchi Chemistry: A Multicultural Chemistry Connection

    Science.gov (United States)

    Murfin, Brian

    2009-01-01

    Connecting science with different cultures is one way to interest students in science, to relate science to their lives, and at the same time to broaden their horizons in a variety of ways. In the lesson described here, students make kimchi, a delicious and popular Korean dish that can be used to explore many important chemistry concepts,…

  15. Chemistry and Nanoscience Research | NREL

    Science.gov (United States)

    Chemistry and Nanoscience Center at NREL investigates materials and processes for converting renewable and new technologies. NREL's primary research in the chemistry and nanoscience center includes the Electrochemical Engineering and Materials Chemistry Providing a knowledge base in materials science covering

  16. System approach to chemistry course

    OpenAIRE

    Lorina E. Kruglova; Valentina G. Derendyaeva

    2010-01-01

    The article considers the raise of chemistry profile for engineers and constructors training, discloses the system approach to chemistry course and singles out the most important modules from the course of general chemistry for construction industry.

  17. Development of precipitator of fluid film type

    International Nuclear Information System (INIS)

    Liu Yupu

    1987-01-01

    The precipitator of fluid film type is developed for the determination of fuel element cladding failure of water-cooled reactor. It integrates the scrubber, precipitator and detector. The jet of element cooling water automatically circulates carrier gas and the flow water film transfers precipitates onto the surface of centre electrode. Three different types are designed. On the special test loop, the uranium sample pellets of simulating cladding failure is measured. The sensitivity of precipitators, saturated precipitation voltage, incremental speed of signal, speed of driving out precipitates and the contents of the precipitates are determined. The test shows that the precipitators are highly sensitive, reliable, cheap and easy to operate

  18. Electrodeposited Mesoporous ZnO Thin Films as Efficient Photocatalysts for the degradation of dye pollutants

    Czech Academy of Sciences Publication Activity Database

    Pauporté, T.; Rathouský, Jiří

    2007-01-01

    Roč. 111, č. 21 (2007), s. 7639-7644 ISSN 1932-7447 Institutional research plan: CEZ:AV0Z40400503 Keywords : ZnO films * photocatalysis * pollutants Subject RIV: CF - Physical ; Theoretical Chemistry

  19. EMERGING POLLUTANTS, MASS SPECTROMETRY, AND COMMUNICATING SCIENCE: PHARMACEUTICALS IN THE ENVIRONMENT

    Science.gov (United States)

    Historically fundamental to amassing our understanding of environmental processes and chemical pollution is the realm of mass spectrometry (MS) - the mainstay of analytical chemistry - the workhorse that supplies definitive data that environmental scientists and engineers...

  20. Annual report 1987 Chemistry Department

    International Nuclear Information System (INIS)

    Funck, J.; Larsen, E.; Nielsen, O.J.

    1988-04-01

    This report contains a brief survey of the main activities in the Chemistry Department. The names and abstracts of all articles and reports published and lectures given in 1987 are presented. The facilities and equipment are mentioned briefly. The activities are divided into the following groups: radioisotope chemistry, analytical- and organic chemistry, environmental chemistry, polymer chemistry, radical chemistry, mineral processing, and general. 13 ills., (author)

  1. Annual report 1982 chemistry department

    International Nuclear Information System (INIS)

    Larsen, E.; Nielsen, O.J.

    1983-04-01

    The work going on in the Risoe National Laboratory, Chemistry Department is briefly surveyed by a presentation of all articles and reports published in 1982. The facilities and equipment are barely mentioned. The papers are divided into eight activities: 1. neutron activation analysis 2. analytical- and organic chemistry 3. environmental chemistry 4. polymer chemistry 5. geochemistry 6. radical chemistry 7. poitron annihilation 8. uranium process chemistry. (author)

  2. Nitrogenous air pollutants: Chemical and biological implications

    International Nuclear Information System (INIS)

    Grosjean, D.

    1979-01-01

    Theoretical and experimental studies on the health effects and chemistry of gaseous and particulate nitrogenous air pollutants are presented. Specific topics include Fourier transform infrared studies of nitrogenous compounds, the mechanism of peroxynitric acid formation, N-nitroso compounds in the air, the chemical transformations of nitrogen oxides during the sampling of combustion products, the atmospheric chemistry of peroxy nitrates, and the effects of nitrogen dioxide on lung metabolism. Attention is also given to the interaction of nitrogen oxides and aromatic hydrocarbons under simulated atmospheric conditions, the characterization of particulate amines, the role of ammonia in atmospheric aerosol chemistry, the relationship between sulfates and nitrates and tropospheric measurements of nitric acid vapor and particulate nitrates

  3. Overview of Megacity Air Pollutant Emissions and Impacts

    Science.gov (United States)

    Kolb, C. E.

    2013-05-01

    The urban metabolism that characterizes major cities consumes very large qualities of humanly produced and/or processed food, fuel, water, electricity, construction materials and manufactured goods, as well as, naturally provided sunlight, precipitation and atmospheric oxygen. The resulting urban respiration exhalations add large quantities of trace gas and particulate matter pollutants to urban atmospheres. Key classes of urban primary air pollutants and their sources will be reviewed and important secondary pollutants identified. The impacts of these pollutants on urban and downwind regional inhabitants, ecosystems, and climate will be discussed. Challenges in quantifying the temporally and spatially resolved urban air pollutant emissions and secondary pollutant production rates will be identified and possible measurement strategies evaluated.

  4. Annual Report 1984. Chemistry Department

    DEFF Research Database (Denmark)

    Funck, Jytte; Nielsen, Ole John

    This report contains a brief survey of the main activities in the Chemistry Department. All articles and reports published and lectures given in 1984 are presented. The facilities and equipment are mentioned briefly. The activities are divided into the following groups: radioisotope chemistry, an......, analytical- and organic chemistry, environmental chemistry, polymer chemistry, geochemistry and waste disposal, radical chemistry, positron annihilation, mineral processing, and general.......This report contains a brief survey of the main activities in the Chemistry Department. All articles and reports published and lectures given in 1984 are presented. The facilities and equipment are mentioned briefly. The activities are divided into the following groups: radioisotope chemistry...

  5. Atmospheric pollution. From processes to modelling

    International Nuclear Information System (INIS)

    Sportisse, B.

    2008-01-01

    Air quality, greenhouse effect, ozone hole, chemical or nuclear accidents.. All these phenomena are tightly linked to the chemical composition of atmosphere and to the atmospheric dispersion of pollutants. This book aims at supplying the main elements of understanding of 'atmospheric pollutions': stakes, physical processes involved, role of scientific expertise in decision making. Content: 1 - classifications and scales: chemical composition of the atmosphere, vertical structure, time scales (transport, residence); 2 - matter/light interaction: notions of radiative transfer, application to the Earth's atmosphere; 3 - some elements about the atmospheric boundary layer: notion of scales in meteorology, atmospheric boundary layer (ABL), thermal stratification and stability, description of ABL turbulence, elements of atmospheric dynamics, some elements about the urban climate; 4 - notions of atmospheric chemistry: characteristics, ozone stratospheric chemistry, ozone tropospheric chemistry, brief introduction to indoor air quality; 5 - aerosols, clouds and rains: aerosols and particulates, aerosols and clouds, acid rains and leaching; 6 - towards numerical simulation: equation of reactive dispersion, numerical methods for chemistry-transport models, numerical resolution of the general equation of aerosols dynamics (GDE), modern simulation chains, perspectives. (J.S.)

  6. Moderator Chemistry Program

    International Nuclear Information System (INIS)

    Dewitt, L.V.; Gibbs, A.; Lambert, D.P.; Bohrer, S.R.; Fanning, R.L.; Houston, M.W.; Stinson, S.L.; Deible, R.W.; Abdel-Khalik, S.I.

    1990-11-01

    Over the past fifteen months, the Systems Chemistry Group of the Reactor Engineering Department has undertaken a comprehensive study of the Department's moderator chemistry program at Savannah River Site (SRS). An internal review was developed to formalize and document this program. Objectives were as outlined in a mission statement and action plan. In addition to the mission statement and action plan, nine separate task reports have been issued during the course of this study. Each of these task reports is included in this document as a chapter. This document is an organized compilation of the individual reports issued by the Systems Chemistry Group in assessment of SRS moderator chemistry to determine if there were significant gaps in the program as ft existed in October, 1989. While these reviews found no significant gaps in that mode of operation, or any items that adversely affected safety, items were identified that could be improved. Many of the items have already been dear with or are in the process of completion under this Moderator Chemistry Program and other Reactor Restart programs. A complete list of the items of improvement found under this assessment is found in Chapter 9, along with a proposed time table for correcting remaining items that can be improved for the chemistry program of SRS reactors. An additional external review of the moderator chemistry processes, recommendations, and responses to/from the Reactor Corrosion Mitigation Committee is included as Appendix to this compilation

  7. Chemistry of Technetium

    International Nuclear Information System (INIS)

    Omori, Takashi

    2001-01-01

    Since the late 1970's the coordination chemistry of technetium has been developed remarkably. The background of the development is obviously related to the use of technetium radiopharmaceuticals for diagnosis in nuclear medicine. Much attention has also been denoted to the chemical behavior of environmental 99 Tc released from reprocessing plants. This review covers the several aspects of technetium chemistry, including production of radioisotopes, analytical chemistry and coordination chemistry. In the analytical chemistry, separation of technetium, emphasizing chromatography and solvent extraction, is described together with spectrophotometric determination of technetium. In the coordination chemistry of technetium, a characteristic feature of the chemistry of Tc(V) complexes is referred from the view point of the formation of a wide variety of highly stable complexes containing the Tc=O or Tc≡N bond. Kinetic studies of the preparation of Tc(III) complexes using hexakis (thiourea) technetium(III) ion as a starting material are summarized, together with the base hydrolysis reactions of Tc(III), Tc(IV) and Tc(V) complexes. (author)

  8. Air Pollution Prevention and Control Policy in China.

    Science.gov (United States)

    Huang, Cunrui; Wang, Qiong; Wang, Suhan; Ren, Meng; Ma, Rui; He, Yiling

    2017-01-01

    With rapid urbanization and development of transport infrastructure, air pollution caused by multiple-pollutant emissions and vehicle exhaust has been aggravated year by year in China. In order to improve air quality, the Chinese authorities have taken a series of actions to control air pollution emission load within a permissible range. However, although China has made positive progress on tackling air pollution, these actions have not kept up with its economy growth and fossil-fuel use. The traditional single-pollutant approach is far from enough in China now, and in the near future, air pollution control strategies should move in the direction of the multiple-pollutant approach. In addition, undesirable air quality is usually linked with the combination of high emissions and adverse weather conditions. However, few studies have been done on the influence of climate change on atmospheric chemistry in the global perspective. Available evidence suggested that climate change is likely to exacerbate certain kinds of air pollutants including ozone and smoke from wildfires. This has become a major public health problem because the interactions of global climate change, urban heat islands, and air pollution have adverse effects on human health. In this chapter, we first review the past and current circumstances of China's responses to air pollution. Then we discuss the control challenges and future options for a better air quality in China. Finally, we begin to unravel links between air pollution and climate change, providing new opportunities for integrated research and actions in China.

  9. Laser experiments for chemistry and physics

    CERN Document Server

    Compton, Robert N

    2016-01-01

    Lasers are employed throughout science and technology, in fundamental research, the remote sensing of atmospheric gases or pollutants, communications, medical diagnostics and therapies, and the manufacturing of microelectronic devices. Understanding the principles of their operation, which underlie all of these areas, is essential for a modern scientific education. This text introduces the characteristics and operation of lasers through laboratory experiments designed for the undergraduate curricula in chemistry and physics. Introductory chapters describe the properties of light, the history of laser invention, the atomic, molecular, and optical principles behind how lasers work, and the kinds of lasers available today. Other chapters include the basic theory of spectroscopy and computational chemistry used to interpret laser experiments. Experiments range from simple in-class demonstrations to more elaborate configurations for advanced students. Each chapter has historical and theoretical background, as well...

  10. Satellite-Based Precipitation Datasets

    Science.gov (United States)

    Munchak, S. J.; Huffman, G. J.

    2017-12-01

    Of the possible sources of precipitation data, those based on satellites provide the greatest spatial coverage. There is a wide selection of datasets, algorithms, and versions from which to choose, which can be confusing to non-specialists wishing to use the data. The International Precipitation Working Group (IPWG) maintains tables of the major publicly available, long-term, quasi-global precipitation data sets (http://www.isac.cnr.it/ ipwg/data/datasets.html), and this talk briefly reviews the various categories. As examples, NASA provides two sets of quasi-global precipitation data sets: the older Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA) and current Integrated Multi-satellitE Retrievals for Global Precipitation Measurement (GPM) mission (IMERG). Both provide near-real-time and post-real-time products that are uniformly gridded in space and time. The TMPA products are 3-hourly 0.25°x0.25° on the latitude band 50°N-S for about 16 years, while the IMERG products are half-hourly 0.1°x0.1° on 60°N-S for over 3 years (with plans to go to 16+ years in Spring 2018). In addition to the precipitation estimates, each data set provides fields of other variables, such as the satellite sensor providing estimates and estimated random error. The discussion concludes with advice about determining suitability for use, the necessity of being clear about product names and versions, and the need for continued support for satellite- and surface-based observation.

  11. Light pollution : working paper

    NARCIS (Netherlands)

    Lechner, Stefan; Arns, Marieke

    2013-01-01

    Light pollution is one of the fastest growing and most pervasive of environmental pollution (Chepesiuk, 2009). In the last couple of years, a lot of research has been done about the effects of light pollution. The interest in light pollution has been growing in many fields of science, extending from

  12. Chemistry in water reactors

    International Nuclear Information System (INIS)

    Hermansson, H.P.; Norring, K.

    1994-01-01

    The international conference Chemistry in Water Reactors was arranged in Nice 24-27/04/1994 by the French Nuclear Energy Society. Examples of technical program areas were primary chemistry, operational experience, fundamental studies and new technology. Furthermore there were sessions about radiation field build-up, hydrogen chemistry, electro-chemistry, condensate polishing, decontamination and chemical cleaning. The conference gave the impression that there are some areas that are going to be more important than others during the next few years to come. Cladding integrity: Professor Ishigure from Japan emphasized that cladding integrity is a subject of great concern, especially with respect to waterside corrosion, deposition and release of crud. Chemistry control: The control of the iron/nickel concentration quotient seems to be not as important as previously considered. The future operation of a nuclear power plant is going to require a better control of the water chemistry than achievable today. One example of this is solubility control via regulation in BWR. Trends in USA: means an increasing use of hydrogen, minimization of SCC/IASCC, minimization of radiation fields by thorough chemistry control, guarding fuel integrity by minimization of cladding corrosion and minimization of flow assisted corrosion. Stellite replacement: The search for replacement materials will continue. Secondary side crevice chemistry: Modeling and practical studies are required to increase knowledge about the crevice chemistry and how it develops under plant operation conditions. Inhibitors: Inhibitors for IGSCC and IGA as well for the primary- (zinc) as for the secondary side (Ti) should be studied. The effects and mode of operation of the inhibitors should be documented. Chemical cleaning: of heat transfer surfaces will be an important subject. Prophylactic cleaning at regular intervals could be one mode of operation

  13. Ochre precipitates and Acid Mine Drainage in a mine environment

    Czech Academy of Sciences Publication Activity Database

    Máša, B.; Pulišová, Petra; Bezdička, Petr; Michalková, E.; Šubrt, Jan

    2012-01-01

    Roč. 56, č. 1 (2012), s. 9-14 ISSN 0862-5468 R&D Projects: GA MŠk(CZ) MEB0810136 Grant - others:Ministry of Education of the Slovak Republic(SK) VEGA 1/0529/09 Institutional research plan: CEZ:AV0Z40320502 Keywords : ochre precipitate * Acid Mine Drainage (AMD) * X-ray diffraction analysis (XRD) * Scanning electron microscopy (SEM) * specific surface area and porosity Subject RIV: CA - Inorganic Chemistry Impact factor: 0.418, year: 2012

  14. Simulations of Precipitate Microstructure Evolution during Heat Treatment

    Science.gov (United States)

    Wu, Kaisheng; Sterner, Gustaf; Chen, Qing; Jou, Herng-Jeng; Jeppsson, Johan; Bratberg, Johan; Engström, Anders; Mason, Paul

    Precipitation, a major solid state phase transformation during heat treatment processes, has for more than one century been intensively employed to improve the strength and toughness of various high performance alloys. Recently, sophisticated precipitation reaction models, in assistance with well-developed CALPHAD databases, provide an efficient and cost-effective way to tailor precipitate microstructures that maximize the strengthening effect via the optimization of alloy chemistries and heat treatment schedules. In this presentation, we focus on simulating precipitate microstructure evolution in Nickel-base superalloys under arbitrary heat treatment conditions. The newly-developed TC-PRISMA program has been used for these simulations, with models refined especially for non-isothermal conditions. The effect of different cooling profiles on the formation of multimodal microstructures has been thoroughly examined in order to understand the underlying thermodynamics and kinetics. Meanwhile, validations against several experimental results have been carried out. Practical issues that are critical to the accuracy and applicability of the current simulations, such as modifications that overcome mean-field approximations, compatibility between CALPHAD databases, selection of key parameters (particularly interfacial energy and nucleation site densities), etc., are also addressed.

  15. Pollution management system

    DEFF Research Database (Denmark)

    2015-01-01

    A pollution management system comprises an array of one or more inlets and at least one outlet. The one or more inlets are arranged to collect polluted air and supply said polluted air to a polluted air treatment element. The one or more inlets each comprise a respective inlet sensor for measuring...... a level of pollution at the inlet, and the at least one outlet comprises an outlet sensor for measuring a level of pollution at the outlet. The inlet sensors and the outlet sensor are arranged to provide feedback to the polluted air treatment element....

  16. Mathematics for physical chemistry

    CERN Document Server

    Mortimer, Robert G

    2013-01-01

    Mathematics for Physical Chemistry is the ideal supplementary text for practicing chemists and students who want to sharpen their mathematics skills while enrolled in general through physical chemistry courses. This book specifically emphasizes the use of mathematics in the context of physical chemistry, as opposed to being simply a mathematics text. This 4e includes new exercises in each chapter that provide practice in a technique immediately after discussion or example and encourage self-study. The early chapters are constructed around a sequence of mathematical topics, wit

  17. Gas phase ion chemistry

    CERN Document Server

    Bowers, Michael T

    1979-01-01

    Gas Phase Ion Chemistry, Volume 1 covers papers on the advances of gas phase ion chemistry. The book discusses the advances in flow tubes and the measurement of ion-molecule rate coefficients and product distributions; the ion chemistry of the earth's atmosphere; and the classical ion-molecule collision theory. The text also describes statistical methods in reaction dynamics; the state selection by photoion-photoelectron coincidence; and the effects of temperature and pressure in the kinetics of ion-molecule reactions. The energy distribution in the unimolecular decomposition of ions, as well

  18. Spatially Resolved Artificial Chemistry

    DEFF Research Database (Denmark)

    Fellermann, Harold

    2009-01-01

    Although spatial structures can play a crucial role in chemical systems and can drastically alter the outcome of reactions, the traditional framework of artificial chemistry is a well-stirred tank reactor with no spatial representation in mind. Advanced method development in physical chemistry has...... made a class of models accessible to the realms of artificial chemistry that represent reacting molecules in a coarse-grained fashion in continuous space. This chapter introduces the mathematical models of Brownian dynamics (BD) and dissipative particle dynamics (DPD) for molecular motion and reaction...

  19. Experiments in physical chemistry

    CERN Document Server

    Wilson, J M; Denaro, A R

    1968-01-01

    Experiments in Physical Chemistry, Second Edition provides a compilation of experiments concerning physical chemistry. This book illustrates the link between the theory and practice of physical chemistry. Organized into three parts, this edition begins with an overview of those experiments that generally have a simple theoretical background. Part II contains experiments that are associated with more advanced theory or more developed techniques, or which require a greater degree of experimental skill. Part III consists of experiments that are in the nature of investigations wherein these invest

  20. Computational quantum chemistry website

    International Nuclear Information System (INIS)

    1997-01-01

    This report contains the contents of a web page related to research on the development of quantum chemistry methods for computational thermochemistry and the application of quantum chemistry methods to problems in material chemistry and chemical sciences. Research programs highlighted include: Gaussian-2 theory; Density functional theory; Molecular sieve materials; Diamond thin-film growth from buckyball precursors; Electronic structure calculations on lithium polymer electrolytes; Long-distance electronic coupling in donor/acceptor molecules; and Computational studies of NOx reactions in radioactive waste storage

  1. Spatially Resolved Artificial Chemistry

    DEFF Research Database (Denmark)

    Fellermann, Harold

    2009-01-01

    made a class of models accessible to the realms of artificial chemistry that represent reacting molecules in a coarse-grained fashion in continuous space. This chapter introduces the mathematical models of Brownian dynamics (BD) and dissipative particle dynamics (DPD) for molecular motion and reaction......Although spatial structures can play a crucial role in chemical systems and can drastically alter the outcome of reactions, the traditional framework of artificial chemistry is a well-stirred tank reactor with no spatial representation in mind. Advanced method development in physical chemistry has...

  2. DOE fundamentals handbook: Chemistry

    International Nuclear Information System (INIS)

    1993-01-01

    The Chemistry Handbook was developed to assist nuclear facility operating contractors in providing operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of chemistry. The handbook includes information on the atomic structure of matter; chemical bonding; chemical equations; chemical interactions involved with corrosion processes; water chemistry control, including the principles of water treatment; the hazards of chemicals and gases, and basic gaseous diffusion processes. This information will provide personnel with a foundation for understanding the chemical properties of materials and the way these properties can impose limitations on the operation of equipment and systems

  3. Quantitative analysis of precipitation over Fukushima to understand the wet deposition process in March 2011

    Science.gov (United States)

    Yatagai, A.; Onda, Y.; Watanabe, A.

    2012-04-01

    The Great East Japan Earthquake caused a severe accident at the Fukushima-Daiichi nuclear power plant (NPP), leading to the emission of large amounts of radioactive pollutants into the environment. The transport and diffusion of these radioactive pollutants in the atmosphere caused a disaster for residents in and around Fukushima. Studies have sought to understand the transport, diffusion, and deposition process, and to understand the movement of radioactive pollutants through the soil, vegetation, rivers, and groundwater. However, a detailed simulation and understanding of the distribution of radioactive compounds depend on a simulation of precipitation and on the information on the timing of the emission of these radioactive pollutants from the NPP. Past nuclear expansion studies have demonstrated the importance of wet deposition in distributing pollutants. Hence, this study examined the quantitative precipitation pattern in March 2011 using rain-gauge observations and X-band radar data from Fukushima University. We used the AMeDAS rain-gauge network data of 1) the Japan Meteorological Agency (1273 stations in Japan) and 2) the Water Information System (47 stations in Fukushima prefecture) and 3) the rain-gauge data of the Environmental Information Network of NTT Docomo (30 stations in Fukushima) to construct 0.05-degree mesh data using the same method used to create the APHRODITE daily grid precipitation data (Yatagai et al., 2009). Since some AMeDAS data for the coastal region were lost due to the earthquake, the complementary network of 2) and 3) yielded better precipitation estimates. The data clarified that snowfall was observed on the night of Mar 15 into the morning of Mar 16 throughout Fukushima prefecture. This had an important effect on the radioactive contamination pattern in Fukushima prefecture. The precipitation pattern itself does not show one-on-one correspondence with the contamination pattern. While the pollutants transported northeast of the

  4. Temporal-spatial variation and the influence factors of precipitation in Sichuan Province, China

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Precipitation is a key factor in the water cycle.At the same time,precipitation is the focus of study in meteorology and climatology,ecological environmental assessment,non-point source pollution and so on.Understanding the temporal-spatial variation and the corresponding factors of precipitation has become the object of hydrology and environmentology.Based on the annual precipitation data,we analyzed the spatial distribution of precipitation in Sichuan Province in China as well as the temporal-spatial variation and the corresponding influence factors involved.The results show that the amount of precipitation was abundant,but the spatial distribution was not consistent with it and the amount of precipitation gradually declined from the south-east to the north-west in Sichuan Province,China.Moreover,the spatial distribution was different throughout the years.The result of correlation analysis indicated that elevation,temperature and air pressure were three key factors affecting the amount and distribution of precipitation,and the correlation coefficients were -0.56,0.38 and 0.45 respectively.Notably,the relationship between the slope of topography and precipitation were significantly negative and the average correlation coefficient was -0.28.

  5. Non-thermally activated chemistry

    International Nuclear Information System (INIS)

    Stiller, W.

    1987-01-01

    The subject is covered under the following headings: state-of-the art of non-thermally activated chemical processes; basic phenomena in non-thermal chemistry including mechanochemistry, photochemistry, laser chemistry, electrochemistry, photo-electro chemistry, high-field chemistry, magneto chemistry, plasma chemistry, radiation chemistry, hot-atom chemistry, and positronium and muonium chemistry; elementary processes in non-thermal chemistry including nuclear chemistry, interactions of electromagnetic radiations, electrons and heavy particles with matter, ionic elementary processes, elementary processes with excited species, radicalic elementary processes, and energy-induced elementary processes on surfaces and interfaces; and comparative considerations. An appendix with historical data and a subject index is given. 44 figs., 41 tabs., and 544 refs

  6. Ethics in Science: The Unique Consequences of Chemistry.

    Science.gov (United States)

    Kovac, Jeffrey

    2015-01-01

    This article discusses the ethical issues unique to the science and practice of chemistry. These issues arise from chemistry's position in the middle between the theoretical and the practical, a science concerned with molecules that are of the right size to directly affect human life. Many of the issues are raised by the central activity of chemistry--synthesis. Chemists make thousands of new substances each year. Many are beneficial, but others are threats. Since the development of the chemical industry in the nineteenth century, chemistry has contributed to the deterioration of the environment but has also helped to reduce pollution. Finally, we discuss the role of codes of ethics and whether the current codes of conduct for chemists are adequate for the challenges of today's world.

  7. Catalysis as a foundational pillar of green chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Anastas, Paul T. [White House Office of Science and Technology Policy, Department of Chemistry, University of Nottingham Nottingham, (United Kingdom); Kirchhoff, Mary M. [U.S. Environmental Protection Agency and Trinity College, Washington, DC (United States); Williamson, Tracy C. [U.S. Environmental Protection Agency, Washington, DC (United States)

    2001-11-30

    Catalysis is one of the fundamental pillars of green chemistry, the design of chemical products and processes that reduce or eliminate the use and generation of hazardous substances. The design and application of new catalysts and catalytic systems are simultaneously achieving the dual goals of environmental protection and economic benefit. Green chemistry, the design of chemical products and processes that reduce or eliminate the use and generation of hazardous substances, is an overarching approach that is applicable to all aspects of chemistry. From feedstocks to solvents, to synthesis and processing, green chemistry actively seeks ways to produce materials in a way that is more benign to human health and the environment. The current emphasis on green chemistry reflects a shift away from the historic 'command-and-control' approach to environmental problems that mandated waste treatment and control and clean up through regulation, and toward preventing pollution at its source. Rather than accepting waste generation and disposal as unavoidable, green chemistry seeks new technologies that are cleaner and economically competitive. Utilizing green chemistry for pollution prevention demonstrates the power and beauty of chemistry: through careful design, society can enjoy the products on which we depend while benefiting the environment. The economic benefits of green chemistry are central drivers in its advancement. Industry is adopting green chemistry methodologies because they improve the corporate bottom line. A wide array of operating costs are decreased through the use of green chemistry. When less waste is generated, environmental compliance costs go down. Treatment and disposal become unnecessary when waste is eliminated. Decreased solvent usage and fewer processing steps lessen the material and energy costs of manufacturing and increase material efficiency. The environmental, human health, and the economic advantages realized through green chemistry

  8. Air pollution effects on Quercus Ilex plants

    International Nuclear Information System (INIS)

    Pavone, P.; Salmeri, C.; Spampinato, G.; Fallico, R.; Ferrante, M.

    1996-01-01

    To test air pollution effects on natural forest vegetation, the soil chemistry and the floristic composition of two Quercus ilex L. woods in the Hyblean region (S-E Sicily), unequally exposed to air pollutants are compared. Acidification phenomena are investigated by the soil chemical changes between the trunk base areas, affected by stem flow water, and the surrounding soil, only influenced by canopy drip. Soil chemical changes, floristic poorness and direct damage to the Q. ilex leaves are only detected in the Climiti Mountains holm-oak woods, located near the Siracusa petrochemical complex, while they do not appear at Cava d'Ispica, sited far from any industry and seldom exposed to winds carrying pollutants

  9. Radionuclides in analytical chemistry

    International Nuclear Information System (INIS)

    Tousset, J.

    1984-01-01

    Applications of radionuclides in analytical chemistry are reviewed in this article: tracers, radioactive sources and activation analysis. Examples are given in all these fields and it is concluded that these methods should be used more widely [fr

  10. Electrostatics in Chemistry

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 4; Issue 7. Electrostatics in Chemistry - Molecular Electrostatic Potential: Visualization and Topography. Shridhar R Gadre Pravin K Bhadane. Series Article Volume 4 Issue 7 July 1999 pp 14-23 ...

  11. Organic Chemistry Masterclasses

    Indian Academy of Sciences (India)

    of Science Education that is published monthly by the Academy since January 1996. ...... Modern chemistry is also emerging from molecules derived from the .... photochemical reactions, the traditional correlation diagram approach is more ...

  12. Alcohol combustion chemistry

    KAUST Repository

    Sarathy, Mani; Oß wald, Patrick; Hansen, Nils; Kohse-Hö inghaus, Katharina

    2014-01-01

    . While biofuel production and its use (especially ethanol and biodiesel) in internal combustion engines have been the focus of several recent reviews, a dedicated overview and summary of research on alcohol combustion chemistry is still lacking. Besides

  13. General Chemistry for Engineers.

    Science.gov (United States)

    Kybett, B. D.

    1982-01-01

    Discusses the relationship between molecular structure, intermolecular forces, and tensile strengths of a polymer and suggests that this is a logical way to introduce polymers into a general chemistry course. (Author/JN)

  14. WHAT MAKES CHEMISTRY DIFFICULT?

    African Journals Online (AJOL)

    IICBA01

    School of Natural and Computational Science Dire Dawa University, Ethiopia,. 2 ... lack of teaching aids and the difficulty of the language of chemistry. ... lab every other week consisting of concept pretests on the web, hand-written homework, ...

  15. Indicators: Soil Chemistry

    Science.gov (United States)

    The chemical makeup of the soil can provide information on wetland condition, wetland water quality and services being provided by the wetland ecosystem. Analyzing soil chemistry reveals if the soil is contaminated with a toxic chemical or heavy metal.

  16. The influence of desulfovibrio desulfuricans on neptunium chemistry

    International Nuclear Information System (INIS)

    Soderholm, L.; Williams, C.; Antonio, M. R.; Tischler, M. L.; Markos, M.

    1999-01-01

    The role of biotic Np(V) reduction is studied in light of its potential role in the environmental immobilization of this hazardous radionuclide. The speciation of Np in Desulfovibrio desulfuricans cultures is compared with Np speciation in the spent medium and in the uninoculated medium. Precipitates formed in all three samples. Optical spectroscopy and X-ray absorption near edge structure (XANES) were used to determine that Np(V) is almost quantitatively reduced in all three samples and that the precipitate is an amorphous Np(IV) species. These results demonstrate that the reduction of Np is independent of Desulfovibrio desulfuricans. The underlying chemistry associated with these results is discussed

  17. Measurement of precipitation using lysimeters

    Science.gov (United States)

    Fank, Johann; Klammler, Gernot

    2013-04-01

    Austria's alpine foothill aquifers contain important drinking water resources, but are also used intensively for agricultural production. These groundwater bodies are generally recharged by infiltrating precipitation. A sustainable water resources management of these aquifers requires quantifying real evapotranspiration (ET), groundwater recharge (GR), precipitation (P) and soil water storage change (ΔS). While GR and ΔS can be directly measured by weighable lysimeters and P by separate precipitation gauges, ET is determined by solving the climatic water balance ET = P GR ± ΔS. According to WMO (2008) measurement of rainfall is strongly influenced by precipitation gauge errors. Most significant errors result from wind loss, wetting loss, evaporation loss, and due to in- and out-splashing of water. Measuring errors can be reduced by a larger area of the measuring gaugés surface and positioning the collecting vessel at ground level. Modern weighable lysimeters commonly have a surface of 1 m², are integrated into their typical surroundings of vegetation cover (to avoid oasis effects) and allow scaling the mass change of monolithic soil columns in high measuring accuracy (0.01 mm water equivalent) and high temporal resolution. Thus, also precipitation can be quantified by measuring the positive mass changes of the lysimeter. According to Meissner et al. (2007) also dew, fog and rime can be determined by means of highly precise weighable lysimeters. Furthermore, measuring precipitation using lysimeters avoid common measuring errors (WMO 2008) at point scale. Though, this method implicates external effects (background noise, influence of vegetation and wind) which affect the mass time series. While the background noise of the weighing is rather well known and can be filtered out of the mass time series, the influence of wind, which blows through the vegetation and affects measured lysimeter mass, cannot be corrected easily since there is no clear relation between

  18. Precipitation process for supernate decontamination

    International Nuclear Information System (INIS)

    Lee, L.M.; Kilpatrick, L.L.

    1982-11-01

    A precipitation and adsorption process has been developed to remove cesium, strontium, and plutonium from water-soluble, high-level radioactive waste. An existing waste tank serves as the reaction vessel and the process begins with the addition of a solution of sodium tetraphenylborate and a slurry of sodium titanate to the contained waste salt solution. Sodium tetraphenylborate precipitates the cesium and sodium titanate adsorbs the strontium and plutonium. The precipitate/adsorbate is then separated from the decontaminated salt solution by crossflow filtration. This new process offers significant capital savings over an earlier ion exchange process for salt decontamination. Chemical and small-scale engineering studies with actual waste are reported. The effect of many variables on the decontamination factors and filter performance are defined

  19. Arsenic precipitation from metallurgical effluents

    International Nuclear Information System (INIS)

    Navarro, P.; Vargas, C.; Araya, E.; Martin, I.; Alguacil, F. J.

    2004-01-01

    In the mining-metallurgical companies different liquid effluents are produced, which can contain a series of dissolved elements that are considered dangerous from an environmental point of view. One of these elements is the arsenic, especially in the state of oxidation +5 that can be precipitated as calcium or iron arsenate. To fulfil the environmental requests it should have in solution a content of arsenic lower than 0,5 mg/l and the obtained solid product should be very stable under the condition in which it will be stored. this work looks for the best conditions of arsenic precipitation, until achieving contents in solution lower than such mentioned concentration. Also, the stability of the precipitates was studied. (Author) 7 refs

  20. The theory, direction, and magnitude of ecosystem fire probability as constrained by precipitation and temperature.

    Science.gov (United States)

    Guyette, Richard; Stambaugh, Michael C; Dey, Daniel; Muzika, Rose Marie

    2017-01-01

    The effects of climate on wildland fire confronts society across a range of different ecosystems. Water and temperature affect the combustion dynamics, irrespective of whether those are associated with carbon fueled motors or ecosystems, but through different chemical, physical, and biological processes. We use an ecosystem combustion equation developed with the physical chemistry of atmospheric variables to estimate and simulate fire probability and mean fire interval (MFI). The calibration of ecosystem fire probability with basic combustion chemistry and physics offers a quantitative method to address wildland fire in addition to the well-studied forcing factors such as topography, ignition, and vegetation. We develop a graphic analysis tool for estimating climate forced fire probability with temperature and precipitation based on an empirical assessment of combustion theory and fire prediction in ecosystems. Climate-affected fire probability for any period, past or future, is estimated with given temperature and precipitation. A graphic analyses of wildland fire dynamics driven by climate supports a dialectic in hydrologic processes that affect ecosystem combustion: 1) the water needed by plants to produce carbon bonds (fuel) and 2) the inhibition of successful reactant collisions by water molecules (humidity and fuel moisture). These two postulates enable a classification scheme for ecosystems into three or more climate categories using their position relative to change points defined by precipitation in combustion dynamics equations. Three classifications of combustion dynamics in ecosystems fire probability include: 1) precipitation insensitive, 2) precipitation unstable, and 3) precipitation sensitive. All three classifications interact in different ways with variable levels of temperature.

  1. Improved daily precipitation nitrate and ammonium concentration models for the Chesapeake Bay Watershed

    International Nuclear Information System (INIS)

    Grimm, J.W.; Lynch, J.A.

    2005-01-01

    Daily precipitation nitrate and ammonium concentration models were developed for the Chesapeake Bay Watershed (USA) using a linear least-squares regression approach and precipitation chemistry data from 29 National Atmospheric Deposition Program/National Trends Network (NADP/NTN) sites. Only weekly samples that comprised a single precipitation event were used in model development. The most significant variables in both ammonium and nitrate models included: precipitation volume, the number of days since the last event, a measure of seasonality, latitude, and the proportion of land within 8 km covered by forest or devoted to industry and transportation. Additional variables included in the nitrate model were the proportion of land within 0.8 km covered by water and/or forest. Local and regional ammonia and nitrogen oxide emissions were not as well correlated as land cover. Modeled concentrations compared very well with event chemistry data collected at six NADP/AirMoN sites within the Chesapeake Bay Watershed. Wet deposition estimates were also consistent with observed deposition at selected sites. Accurately describing the spatial distribution of precipitation volume throughout the watershed is important in providing critical estimates of wet-fall deposition of ammonium and nitrate. - A linear least-squares regression approach was used to develop daily precipitation nitrate and ammonium concentration models for the Chesapeake Bay Watershed

  2. Applications of supramolecular chemistry

    CERN Document Server

    Schneider, Hans-Jörg

    2012-01-01

    ""The time is ripe for the present volume, which gathers thorough presentations of the numerous actually realized or potentially accessible applications of supramolecular chemistry by a number of the leading figures in the field. The variety of topics covered is witness to the diversity of the approaches and the areas of implementation…a broad and timely panorama of the field assembling an eminent roster of contributors.""-Jean-Marie Lehn, 1987 Noble Prize Winner in Chemistry

  3. Gas phase ion chemistry

    CERN Document Server

    Bowers, Michael T

    1979-01-01

    Gas Phase Ion Chemistry, Volume 2 covers the advances in gas phase ion chemistry. The book discusses the stabilities of positive ions from equilibrium gas-phase basicity measurements; the experimental methods used to determine molecular electron affinities, specifically photoelectron spectroscopy, photodetachment spectroscopy, charge transfer, and collisional ionization; and the gas-phase acidity scale. The text also describes the basis of the technique of chemical ionization mass spectrometry; the energetics and mechanisms of unimolecular reactions of positive ions; and the photodissociation

  4. Reference Sources in Chemistry

    OpenAIRE

    Sthapit, Dilip Man

    1995-01-01

    Information plays an important role in the development of every field. Therefore a brief knowledge regarding information sources is necessary to function in any field. There are many information sources about scientific and technical subjects. In this context there are many reference sources in Chemistry too. Chemistry is one important part of the science which deals with the study of the composition of substances and the chemical changes that they undergo. The purpose of this report is...

  5. Chemistry and nuclear technology

    International Nuclear Information System (INIS)

    De Wet, W.J.

    1977-01-01

    The underlying principles of nuclear sciece and technology as based on the two basic phenomena, namely, radioactivity and nuclear reactions, with their relatively large associated energy changes, are outlined. The most important contributions by chemists in the overall historical development are mentioned and the strong position chemistry has attained in these fields is indicated. It is concluded that chemistry as well as many other scientific discplines (apart from general benefits) have largely benefitted from these nuclear developments [af

  6. Fundamentals of quantum chemistry

    CERN Document Server

    House, J E

    2004-01-01

    An introduction to the principles of quantum mechanics needed in physical chemistry. Mathematical tools are presented and developed as needed and only basic calculus, chemistry, and physics is assumed. Applications include atomic and molecular structure, spectroscopy, alpha decay, tunneling, and superconductivity. New edition includes sections on perturbation theory, orbital symmetry of diatomic molecules, the Huckel MO method and Woodward/Hoffman rules as well as a new chapter on SCF and Hartree-Fock methods. * This revised text clearly presents basic q

  7. Tropical Soil Chemistry

    DEFF Research Database (Denmark)

    Borggaard, Ole K.

    and environmental protection. Tropical Soil Chemistry by Ole K. Borggaard provides an overview of the composition, occurrence, properties, processes, formation, and environmental vulnerability of various tropical soil types (using American Soil Taxonomy for classification). The processes and the external factors...... soil chemical issues are also presented to assess when, why, and how tropical soils differ from soils in other regions. This knowledge can help agricultural specialists in the tropics establish sustainable crop production. Readers are assumed to be familiar with basic chemistry, physics...

  8. USSR Report, Chemistry

    Science.gov (United States)

    1987-03-17

    New hybrid technologies may also appear, combining chemical precipitation with cathode atomization. All of this will place increased requirements on...spectrophotometry and gravimetry using T-ll glass fabric dressed with vinyl (2-Ethoxyethoxy) silane type GVS-9, plus glass fabric with a paraffin...various forms (direct, precipitation , reduction) of catalytic synthesis are discussed in some detail, as well as situations in which they are

  9. Fungi in a heavy metal precipitating stream in the Mansfeld mining district, Germany

    International Nuclear Information System (INIS)

    Ehrman, James M.; Baerlocher, Felix; Wennrich, Rainer; Krauss, Gerd-Joachim; Krauss, Gudrun

    2008-01-01

    Fungal growth on alder leaves was studied in two heavy metal polluted streams in central Germany. The aim of the study was to examine previously observed differences in leaf decomposition rates, heavy metal precipitation and fungal involvement in these processes at the microscopic level. Ergosterol analyses indicated that neither habitat was optimal for fungi, but leaves exposed at the less polluted site (H8) decomposed rapidly and were colonized externally and internally by fungi and other microorganisms. Leaves exposed at the more polluted site (H4) decomposed very slowly and fungal colonization was restricted to external surfaces. An amorphous organic layer, deposited within 24 h of exposure, quickly became covered with a pale blue-green crystalline deposit (zincowoodwardite) with significant amounts of Al, S, Cu and Zn, determined by energy dispersive X-ray spectroscopy (EDS). Scanning electron microscopy (SEM) analysis of the precipitate revealed a branching arrangement of the precipitated particles caused by the presence of fungal hyphae growing on the surface. Hyphae that were not disturbed by handling were usually completely encased in the precipitate, but hyphae did not contain EDS-detectable amounts of precipitate metals. Elemental analysis using inductively coupled plasma (ICP) atomic emission spectrometry and ICP mass spectrometry revealed continuing accumulation of Zn, Cu and several other metals/metalloids on and in leaves. The formation of metal precipitates on various artificial substrates at site H4 was much reduced compared to leaves, which we attribute to the absence of fungal colonization on the artificial substrates. We could not determine whether fungi accelerate the precipitation of heavy metals at site H4, but mycelial growth on leaves continues to create new surfaces and therefore thicker layers of precipitate on leaves compared to artificial substrates

  10. Fungi in a heavy metal precipitating stream in the Mansfeld mining district, Germany

    Energy Technology Data Exchange (ETDEWEB)

    Ehrman, James M. [Department of Biology, Mount Allison University, 63B York St., Sackville, NB, E4L 1G7 (Canada)], E-mail: jehrman@mta.ca; Baerlocher, Felix [Department of Biology, Mount Allison University, 63B York St., Sackville, NB, E4L 1G7 (Canada); Wennrich, Rainer [Helmholtz Centre for Environmental Research- UFZ, Department of Analytical Chemistry, Permoserstr. 15, 04318 Leipzig (Germany); Krauss, Gerd-Joachim [Martin-Luther-University, Halle-Wittenberg, Institute of Biochemistry and Biotechnology, Div. Ecological and Plant Biochemistry, Kurt-Mothes-Str. 3, 06120 Halle/Saale (Germany); Krauss, Gudrun [Helmholtz Centre for Environmental Research- UFZ, Department of Environmental Microbiology, Theodor-Lieser-Str. 4, 06120 Halle/Saale (Germany)

    2008-01-25

    Fungal growth on alder leaves was studied in two heavy metal polluted streams in central Germany. The aim of the study was to examine previously observed differences in leaf decomposition rates, heavy metal precipitation and fungal involvement in these processes at the microscopic level. Ergosterol analyses indicated that neither habitat was optimal for fungi, but leaves exposed at the less polluted site (H8) decomposed rapidly and were colonized externally and internally by fungi and other microorganisms. Leaves exposed at the more polluted site (H4) decomposed very slowly and fungal colonization was restricted to external surfaces. An amorphous organic layer, deposited within 24 h of exposure, quickly became covered with a pale blue-green crystalline deposit (zincowoodwardite) with significant amounts of Al, S, Cu and Zn, determined by energy dispersive X-ray spectroscopy (EDS). Scanning electron microscopy (SEM) analysis of the precipitate revealed a branching arrangement of the precipitated particles caused by the presence of fungal hyphae growing on the surface. Hyphae that were not disturbed by handling were usually completely encased in the precipitate, but hyphae did not contain EDS-detectable amounts of precipitate metals. Elemental analysis using inductively coupled plasma (ICP) atomic emission spectrometry and ICP mass spectrometry revealed continuing accumulation of Zn, Cu and several other metals/metalloids on and in leaves. The formation of metal precipitates on various artificial substrates at site H4 was much reduced compared to leaves, which we attribute to the absence of fungal colonization on the artificial substrates. We could not determine whether fungi accelerate the precipitation of heavy metals at site H4, but mycelial growth on leaves continues to create new surfaces and therefore thicker layers of precipitate on leaves compared to artificial substrates.

  11. Radar-Derived Quantitative Precipitation Estimation Based on Precipitation Classification

    Directory of Open Access Journals (Sweden)

    Lili Yang

    2016-01-01

    Full Text Available A method for improving radar-derived quantitative precipitation estimation is proposed. Tropical vertical profiles of reflectivity (VPRs are first determined from multiple VPRs. Upon identifying a tropical VPR, the event can be further classified as either tropical-stratiform or tropical-convective rainfall by a fuzzy logic (FL algorithm. Based on the precipitation-type fields, the reflectivity values are converted into rainfall rate using a Z-R relationship. In order to evaluate the performance of this rainfall classification scheme, three experiments were conducted using three months of data and two study cases. In Experiment I, the Weather Surveillance Radar-1988 Doppler (WSR-88D default Z-R relationship was applied. In Experiment II, the precipitation regime was separated into convective and stratiform rainfall using the FL algorithm, and corresponding Z-R relationships were used. In Experiment III, the precipitation regime was separated into convective, stratiform, and tropical rainfall, and the corresponding Z-R relationships were applied. The results show that the rainfall rates obtained from all three experiments match closely with the gauge observations, although Experiment II could solve the underestimation, when compared to Experiment I. Experiment III significantly reduced this underestimation and generated the most accurate radar estimates of rain rate among the three experiments.

  12. Silver precipitation from electrolytic effluents

    International Nuclear Information System (INIS)

    Rivera, I.; Patino, F.; Cruells, M.; Roca, A.; Vinals, J.

    2004-01-01

    The recovery of silver contained in electrolytic effluents is attractive due to its high economic value. These effluents are considered toxic wastes and it is not possible to dump them directly without any detoxification process. One of the most important way for silver recovery is the precipitation with sodium ditionite, sodium borohidride or hydrazine monohidrate. In this work, the most significant aspects related to the use of these reagents is presented. Results of silver precipitation with sodium ditionite from effluents containing thiosulfate without previous elimination of other species are also presented. silver concentration in the final effluents w <1 ppm. (Author) 15 refs

  13. The characterisation of precipitated magnetites

    International Nuclear Information System (INIS)

    Rush, D.F.; Segal, D.L.

    1982-06-01

    Methods are described for the preparation of magnetite by precipitation from aqueous solutions of iron(II) and iron(III) salts. The magnetites have been characterised by transmission electron microscopy, chemical analysis and X-ray diffraction. Transmission Moessbauer spectroscopy has also been used to characterise precipitated magnetites and a comparison of the spectra has been made with those obtained from nickel ferrite and hydrated ferric oxides. The hydrothermal stability of magnetite at 573 K has also been investigated. This work is relevant to corrosion processes that can occur in the water coolant circuits of nuclear reactors. (author)

  14. An Improved Plutonium Trifluoride Precipitation Flowsheet

    Energy Technology Data Exchange (ETDEWEB)

    Harmon, H.D.

    2001-06-26

    This report discusses results of the plutonium trifluoride two-stage precipitation study. A series of precipitation experiments was used to identify the significant process variables affecting precipitation performance. A mathematical model of the precipitation process was developed which is based on the formation of plutonium fluoride complexes. The precipitation model relates all process variables, in a single equation, to a single parameter which can be used to control the performance of the plutonium trifluoride precipitation process. Recommendations have been made which will optimize the FB-Line plutonium trifluoride precipitation process.

  15. An Improved Plutonium Trifluoride Precipitation Flowsheet

    International Nuclear Information System (INIS)

    Harmon, H.D.

    2001-01-01

    This report discusses results of the plutonium trifluoride two-stage precipitation study. A series of precipitation experiments was used to identify the significant process variables affecting precipitation performance. A mathematical model of the precipitation process was developed which is based on the formation of plutonium fluoride complexes. The precipitation model relates all process variables, in a single equation, to a single parameter which can be used to control the performance of the plutonium trifluoride precipitation process. Recommendations have been made which will optimize the FB-Line plutonium trifluoride precipitation process

  16. Impact of acid precipitation on freshwater ecosystems in Norway

    Energy Technology Data Exchange (ETDEWEB)

    Wright, R F; Dale, T; Gjessing, E T; Hendrey, G R; Henriksen, A; J Hannesen, M; Muniz, I P

    1975-01-01

    Precipitation in southern Norway contains large amounts of H/sup +/, SO/sub 4//sup 2 -/, and NO/sub 3//sup -/ ions, along with heavy metals such as Cu, Zn, Cd, and Pb. These pollutants are transported over long distances to Scandinavia and are deposited in precipitation and dry-fallout. Large areas of southern Norway have been adversely affected by acid precipitation. The pH of many lakes is below 5.0 and sulfate, rather than bicarbonate, is the major anion. Lakes in these areas are particularly vulnerable to acid precipitation because their watersheds are underlain by highly resistant bedrock with low calcium and magnesium contents. The effects of the increasing acidity of freshwater ecosystems involve interference at every trophic level. Biological surveys indicate that low pH-values inhibit the decomposition of allochthonous organic matter, decrease the species number of phyto- and zooplankton and benthic invertebrates, and promote the growth of benthic mosses. Fish populations have been severely affected - the salmon have been eliminated from many rivers, and hundreds of lakes have lost their sport fisheries.

  17. Henry Taube and Coordination Chemistry

    Science.gov (United States)

    dropdown arrow Site Map A-Z Index Menu Synopsis Henry Taube and Coordination Chemistry Resources with Professor of Chemistry, Emeritus, at Stanford University, received the 1983 Nobel Prize in Chemistry " there from 1940-41. "I became deeply interested in chemistry soon after I came to Berkeley,"

  18. The radiation chemistry of colloids

    International Nuclear Information System (INIS)

    Sellers, R.M.

    1976-08-01

    One of the most important problems associated with water cooled reactors is the accumulation on the pipework of radio-active deposits. These are formed from corrosion products which become activated during their passage through the reactor core. The first step of the activation process involves the deposition of the corrosion products, which are present as either colloidal or particulate matter, onto surfaces in the reactor core, i.e. within the radiation zone. A review of the literature on the effect of radiation on colloids is presented. Particular emphasis is given to the dependence of colloidal parameters such as particle size, turbidity and electrophoretic mobility on radiation dose. Most of the data available is of a qualitative nature only. Evidence is presented that colloids of iron are affected (in some cases precipitated) by radiation, and it is suggested that this process plays a part in the deposition of corrosion products in nuclear reactor cores. The bulk of the information available can be rationalized in terms of the radiation chemistry of aqueous solutions, and the interaction of the radicals produced with the atoms or molecules at the surface of the colloidal particles. This approach is very successful in explaining the variation of the mean particle size of monodisperse sulphur hydrosols with dose, for which quantitative experimental data are available. (author)

  19. Precipitation washout (a bibliography with abstracts). Report for 1964-Jun 76

    International Nuclear Information System (INIS)

    Brown, R.J.

    1976-06-01

    The reports cited in this bibliography cover the removal of pollutants, radioactive isotopes, and dust by rain and snow. The theory, modeling, sampling, and effects of precipitation washout are presented. (This updated bibliography contains 95 abstracts, 21 of which are new entries to the previous edition.)

  20. The assessment of the existing measuring system for atmospheric precipitation control around Belchatow power plant and a concept of its changing

    International Nuclear Information System (INIS)

    Hryniewicz, R.

    1993-01-01

    The influence of fossil-fuel power plants on environment is also demonstrated by pollution of atmospheric precipitation with combustion products emitted to the atmosphere. Actual methods for the precipitation pollution control have been critically reviewed and their use fullness discussed. A new concept has been proposed for that purpose. The detailed analysis of chemical nature of effluents present in rain waters and their physical parameters will be used for environment state assessment in the future