WorldWideScience

Sample records for acid precipitation provisions

  1. Acid Precipitation and the Forest Ecosystem

    Science.gov (United States)

    Dochinger, Leon S.; Seliga, Thomas A.

    1975-01-01

    The First International Symposium on Acid Precipitation and the Forest Ecosystem dealt with the potential magnitude of the global effects of acid precipitation on aquatic ecosystems, forest soils, and forest vegetation. The problem is discussed in the light of atmospheric chemistry, transport, and precipitation. (Author/BT)

  2. Acid precipitation - Effects on forest and fish

    Energy Technology Data Exchange (ETDEWEB)

    Overrein, L.N.; Seip, H.M.; Tollan, A.

    1980-01-01

    The Norwegian Interdisciplinary Research Programme 'Acid Precipitation - Effects on Forest and Fish' (The SNSF-project) was initiated in 1972. The main objectives of the SNSF-project have been to: (1) establish as precisely as possible the effects of acid precipitation on forest and freshwater fish, (2) investigate the effects of air pollutants on soil, vegetation and water, required to satisfy point 1. The final report summarizes the results of the entire program on the basis of some 300 SNSF reports and data presented in various international journals in the period 1972-80. Attention is given to emissions and transport, atmospheric deposits in Norway, water acidification - status and trends, chemical modifications of precipitation in contact with soil and vegetation, snow and snowmelt, land-use changes and acidification, conceptual models for water acidification, effects of acid precipitation on soil productivity and plant growth, and effects of acid water on aquatic life.

  3. Precipitation of humic acid with divalent ions

    DEFF Research Database (Denmark)

    Andersen, Niels Peder Raj; Mikkelsen, Lene Haugaard; Keiding, Kristian

    2001-01-01

    HA concentration. With respect to region III, it is not exclusively determined whether precipitation is caused by HA behaving as a polyelectrolyte or possessing colloidal properties. The general observation throughout is that HA appears to behave as a polyelectrolyte at low concentrations......The aim of this study is to investigate precipitation proper-ties of humic acid (HA). This is done by studying a commercial available humic acid salt (HA) from which a phase diagram is established by adding various amounts of BaCl2 to different concentrations of HA at pH 5.5. The phase diagram...... shows tree characteristic regions with markedly different precipitation courses: region I at HA concentration below 0.15g/l, region H at HA concentration between 0.15 and similar to2g/l and rgeion IV at HA concentration above 3.5g/l. Furthermore, a forth intermediate region M is observed between similar...

  4. Biologically produced acid precipitable polymeric lignin

    Science.gov (United States)

    Crawford, Don L.; Pometto, III, Anthony L.

    1984-01-01

    A water soluble, acid precipitable polymeric degraded lignin (APPL), having a molecular weight of at least 12,000 daltons, and comprising, by percentage of total weight, at least three times the number of phenolic hydroxyl groups and carboxylic acid groups present in native lignin. The APPL may be modified by chemical oxidation and reduction to increase its phenolic hydroxyl content and reduce the number of its antioxidant inhibitory side chains, thereby improving antioxidant properties.

  5. 40 CFR 75.3 - General Acid Rain Program provisions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false General Acid Rain Program provisions. 75.3 Section 75.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTINUOUS EMISSION MONITORING General § 75.3 General Acid Rain Program provisions....

  6. Effects of acid precipitation on inland waters

    Energy Technology Data Exchange (ETDEWEB)

    Tollan, A.

    1981-01-01

    Atmospheric transport of sulfur compounds and other acidifying components has led to extensive regional acidification of water bodies in sensitive areas, both in Europe and North America. The regions affected by acidification are increasing in area at present. Lakes in these areas are now characterized by low pH, high contents of sulfate and high concentrations of several metals, notably aluminium, which is leached from the catchments under impact of acid precipitation. Acidification of inland waters has had major effects on life in rivers and lakes. Investigations have shown that all types of organisms in the freshwater ecosystem are affected by acidification, ecosystem structures are simplified, and the lakes probably become poorer in nutrients. A prominent feature of regional water acidification is the extensive loss of fish populations, caused primarily by reproductive failure. Physiological stress and fish kills are caused by toxic combinations of water acidity and high aluminium content.

  7. 40 CFR 76.3 - General Acid Rain Program provisions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false General Acid Rain Program provisions. 76.3 Section 76.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.3 General Acid Rain Program...

  8. Acid precipitation: effects on forest and fish. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Overrein, L.N.; Seip, H.M.; Tollan, A.

    1980-12-01

    This interdisciplinary research program was launched in 1972 in response to concern in Scandinavian countries that acid precipitation was causing changes to the natural environment. A major hypothesis was that anthropogenic release of sulfur oxides and other pollutants may alter geobiochemical and biochemical cycles with consequences for the biota. The main research efforts were directed towards possible threats to forest and freshwater fish. Results of the entire program are summarized. Information is presented under the following section headings: emissions and transport; atmospheric deposits in Norway; water acidification - status and trends; chemical modifications of precipitation in contact with soil and vegetation; snow and snowmelt; land-use changes and acidification; effects of acid precipitation on soil productivity and plant growth; and effects of acid water on aquatic life.

  9. Tracing of salicylic acid additive during precipitation of zirconium

    International Nuclear Information System (INIS)

    This paper presents the results of experimental study carried out to know whether the salicylic acid used as an additive during the precipitation of zirconium using ammonium hydroxide solution goes into the filtrate, remains in the hydrated zirconia or gets distributed between the both under the ambient conditions of precipitation. Keeping its simplicity and amenability to adopt on a routine basis, spectrophotometric method has been chosen for the purpose among the many methods available and the problems associated in determining salicylic acid in the presence of zirconium and the medial measures to circumvent the same have been brought out in detail. (author)

  10. Acidic precipitation: considerations for an air-quality standard

    Energy Technology Data Exchange (ETDEWEB)

    Evans, L.S.; Hendrey, G.R.; Stensland, G.J.; Johnson, D.W.; Francis, A.J.

    1980-01-01

    Acidic precipitation, wet or frozen deposition with a hydrogen ion concentration greatern than 2.5 ..mu..eq l/sup -1/ is a significant air pollution problem in the United States. The chief anions accounting for the hydrogen ions in rainfall are nitrate and sulfate. Agricultural systems are more likely to derive net nutritional benefits from increasing inputs of acidic rain than are forest systems when soils alone are considered. Agricultural soils may benefit because of the high N and S requirements of agricultural plants. Detrimental effects to forest soils may result if atmospheric H/sup +/ inputs significantly add to or exceed H/sup +/ production by soils. Acidification of fresh waters of southern Scandinavia, southwestern Scotland, southeastern Canada, and northeastern United States is caused by acid deposition. Areas of these regions in which this acidification occurs have in common, highly acidic precipitation with volume weighted mean annual H/sup +/ concentrations of 25 ..mu..eq l/sup -1/ or higher and slow weathering granitic or precambrian bedrock with thin soils deficient in minerals which would provide buffer capacity. Biological effects of acidification of fresh waters are detectable below pH 6.0. As lake and stream pH levels decrease below pH. 6.0, many species of plants, invertebrates, and vertebrates are progressively eliminated. Generally, fisheries are impacted below pH 5.0 and are completely destroyed below pH 4.8. There are few studies that document effects of acidic precipitation on terrestrial vegetation to establish an air quality standard. It must be demonstrated that current levels of precipitation acidity alone significantly injure terrestrial vegetation. In terms of documented damanges, current research indicates that establishing a standard for precipitation for the volume weighted annual H/sup +/ concentration at 25 ..mu..eq l/sup -1/ may protect the most sensitive areas from permanent lake acidification.

  11. Third generation capture system: precipitating amino acid solvent systems

    NARCIS (Netherlands)

    Sanchez Fernandez, E.; Misiak, K.; Ham, L. van der; Goetheer, E.L.V.

    2013-01-01

    This work summarises the results of the design of novel separation processes for CO2 removal from flue gas based on precipitating amino acid solvents. The processes here described (DECAB, DECAB Plus and pH-swing) use a combination of enhanced CO2 absorption (based on the Le Chatelier’s principle) an

  12. Acid precipitation--a new study from Norway

    Energy Technology Data Exchange (ETDEWEB)

    Bell, J.N.B.

    1981-07-16

    Public concern over acid rain has nowhere been more evident than in Norway, where in the mountainous regions of the south, an accelerating decline in fish stocks has led to the extinction of fish populations in an area over 13,000 km/sup 2/, with severe problems over another 20,000 km/sup 2/. This has stimulated the establishment of a major Norwegian interdisciplinary research program into the biological effects of acid precipitation, which has recently terminated after 8 years. The numerous reports published on the findings of the project have now been summarized in ''Acid precipitation - effects on forest and fish'', by Overrein, Seip, and Tollan. This summary report is briefly discussed and reviewed. (JMT)

  13. Precipitation of silicic acid from geothermal water by addition of cetyl-trimethyl-ammonium bromide

    Energy Technology Data Exchange (ETDEWEB)

    Kitsuki, Harumi; Yokoyama, Takushi; Shimada, Kanichi; Yamanaka, Chiho; Nishu, Keisuke; Shimizu, Shin; Tarutani, Toshikazu

    1986-01-25

    Cetyl-trimethyl-ammonium bromide (CTAB) was added to sodium silicate solution and geothermal hot water (Ohtake Geothermal Power Plant and Hatchobaru Geo-thermal Power Plant) to precipitate silica. 1) CTA ions do not react with monosilicic acid, but only the polymerization among the polysilicic acids proceeds and causes silica to precipitate. Optimum pH for the silica precipitation is 6 - 7 and the higher concentration of polysilicic acid will cause more precipitation. 2) When added to geothermal hot water, the silica precipita-tion increases with the increase of CTAB concentration within the range of 10/sup -7/ - 10/sup -4/ mol dm/sup 3/ concentration. Almost all poly-silicic acid precipitated at 10/sup -4/ mol dm/sup 3/ when measured for silica precipitation after 5 minutes. Total concentration of silicic acid was higher in the Hatchobaru geothermal water than that of the Ohtake geothermal water. (10 figs, 14 refs)

  14. Effects of precipitation on soil acid phosphatase activity in three successional forests in southern China

    OpenAIRE

    W. Huang; Liu, J; Zhou, G.; Zhang, D; Deng, Q

    2011-01-01

    Phosphorus (P) is often a limiting nutrient for plant growth in tropical and subtropical forests. Global climate change has led to alterations in precipitation in the recent years, which inevitably influences P cycling. Soil acid phosphatase plays a vital role in controlling P mineralization, and its activity reflects the capacity of organic P mineralization potential in soils. In order to study the effects of precipitation on soil acid phosphatase activity, an experiment with precipitation t...

  15. Indium sulfide precipitation from hydrochloric acid solutions of calcium and sodium chlorides

    International Nuclear Information System (INIS)

    The effect of precipitation duration, acid concentration, indium complexing with chloride ions on the process of indium sulfide chemical precipitation in hydrochloric acid solutions, precipitate composition and dispersity are studied. It is established that indium sulfide solubility increases in solutions with acid concentration exceeding 0.40-0.45 mol/l. Calcium and indium chloride addition to diluted hydrochloric solutions greatly increases the solubility of indium sulfide. The effect of calcium chloride on In2S3 solubility is higher than that of sodium chloride

  16. Effects of precipitation on soil acid phosphatase activity in three successional forests in southern China

    Directory of Open Access Journals (Sweden)

    W. Huang

    2011-07-01

    Full Text Available Phosphorus (P is often a limiting nutrient for plant growth in tropical and subtropical forests. Global climate change has led to alterations in precipitation in the recent years, which inevitably influences P cycling. Soil acid phosphatase plays a vital role in controlling P mineralization, and its activity reflects the capacity of organic P mineralization potential in soils. In order to study the effects of precipitation on soil acid phosphatase activity, an experiment with precipitation treatments (no precipitation, natural precipitation and doubled precipitation in three successional forests in southern China was carried out. The three forests include Masson pine forest (MPF, coniferous and broad-leaved mixed forest (MF and monsoon evergreen broad-leaved forest (MEBF. Results showed that driven by seasonality of precipitation, changes in soil acid phosphatase activities coincided with the seasonal climate pattern, with significantly higher values in the wet season than in the dry season. Soil acid phosphatase activities were closely linked to forest successional stages, with enhanced values in the later stages of forest succession. In the dry season, soil acid phosphatase activities in the three forests showed a rising trend with increasing precipitation treatments. In the wet season, soil acid phosphatase activity was depressed by no precipitation treatment in the three forests. However, doubled precipitation treatment exerted a significantly negative effect on it only in MEBF. These results indicate that the potential transformation rate of organic P might be more dependent on water in the dry season than in the wet season. A decrease in organic P turnover would occur in the three forests if there was a drought in a whole year in the future. More rainfall in the wet season would also be adverse to organic P turnover in MEBF due to its high soil moisture.

  17. Analysis of process configurations for CO2 capture by precipitating amino acid solvents

    NARCIS (Netherlands)

    Sanchez Fernandez, E.; Heffernan, K.; Ham, L.V. van der; Linders, M.J.G.; Brilman, D.W.F.; Goetheer, E.L.V.; Vlugt, T.J.H.

    2014-01-01

    Precipitating amino acid solvents are an alternative to conventional amine scrubbing for CO2 capture from flue gas. Process operation with these solvents leads to the formation of precipitates during absorption that need to be re-dissolved prior to desorption of CO2. The process configuration is cru

  18. Struvite Precipitation for Ammonia Nitrogen Removal in 7-Aminocephalosporanic Acid Wastewater

    OpenAIRE

    Erhong Duan; Jingliang Yang; Ping Chen; Yanfang Liu; Jiane Zuo; Zaixing Li; Xuguang Ren; Yongjun Wang

    2012-01-01

    7-Aminocephalosporanic acid wastewater usually contains high concentrations of ammonium (NH4+-N), which is known to inhibit nitrification during biological treatment processes. Chemical precipitation is a useful technology to remove ammonium from wastewater. In this paper, the removal of ammonium from 7-aminocephalosporanic acid wastewater was studied. The optimum pH, molar ratio, and various chemical compositions of magnesium ammonium phosphate (MAP) precipitation were investigated. The resu...

  19. Effects of acid precipitation alone and in combination with sulfur dioxide on field-grown soybeans

    Energy Technology Data Exchange (ETDEWEB)

    Irving, P. M.; Miller, J. E.

    1979-01-15

    In view of the increasing prevalence of acid precipitation in the Midwest, a study was undertaken in 1977 to determine its effects, and possible interactions with SO/sub 2/, on soybeans, an economically important crop in the Midwest. The findings to date are summarized. Field-grown soybeans were exposed to acid (approx. pH 3.1) or control (approx. pH 5.3) precipitation simulants in sulfur dioxide fumigated and unfumigated field plots as described previously. No statistically significant effects of the acid or control simulants, nor interactions with SO/sub 2/, were found on seed yield in either year, although the plots receiving both precipitation simulant and SO/sub 2/ had significantly lower yields (12 to 46%) than plots receiving only precipitation simulant. In 1977 the seed yields were slightly lower in both the fumigated and unfumigated acid-treated plots, when compared to the appropriate controls, while in 1978, yields in the unfumigated, acid-treated plots were somewhat higher. It is interesting to note that the weights of individual seeds were consistent with the yield differences; in 1978 the seed weight in the acid precipitation plot was significantly different from that in plots both with control precipitation and no precipitation. This suggests that the acid treatment in 1978 did, in fact, have an effect on productivity as reflected seed growth. Although visible damage was not apparent in any of the plots, a histological study revealed significant increases in the number of dead leaf cells in all plots, compared to untreated controls, except the one exposed to control precipitation alone.

  20. Potential health implications for acid precipitation, corrosion, and metals contamination of drinking water.

    OpenAIRE

    Sharpe, W E; DeWalle, D R

    1985-01-01

    Potential health effects of drinking water quality changes caused by acid precipitation are presented. Several different types of water supply are discussed and their roles in modifying acid rain impacts on drinking water are explained. Sources of metals contamination in surface water supplies are enumerated. The authors present some results from their research into acid rain impacts on roof-catchment cisterns, small surface water supplies, and lead mobilization in acid soils. A good correlat...

  1. Considerations of an air-quality standard to protect terrestrial vegetation from acidic precipitation

    Energy Technology Data Exchange (ETDEWEB)

    Evans, L.S.

    1981-01-01

    Studies on the effects of acidic precipitation which is here defined as wet or frozen deposition with a hydrogen ion concentration greater than 2.5 ..mu..eq 1/sup -1/, are reviewed. At the present time there is an inadequate amount of information that shows decreases in crop growth except for one field study. Most studies with plants (crops and forests) are inadequate for standard setting because they are not conducted in the field with adequate randomization of plots coupled with rigorous statistical analyses. Although visible injury to foliage has been documented in a variety of greenhouse studies, no experimental evidence demonstrates loss of field crop value or reduction in plant productivity due to visible foliar injury. Acidic precipitation can contribute nutrients to vegetation and could also influence leaching rates of nutrients from vegetation. Although these processes occur, there are no data that show changes in nutrient levels in foliage that relate to crop or natural ecosystem productivity. Experimental results show that fertilization of ferns is inhibited by current levels of acidic precipitation in the northeastern United States. However, the overall impacts of inhibited fertilization on perpetuation of the species or ecosystem productivity have not been evaluated. Simulated acidic precipitation has been shown to effect plant pathogens in greenhouse and field experiments. Simulated acidic precipitation inhibited pathogen activities under some circumstances and promoted pathogen activities under other circumstances. No conclusion can be drawn about the effects of current levels of precipitation acidity on plant pathogen-host interactions. From these data it must be concluded that research on the effects of acidic precipitation on terrestrial vegetation is too meager to draw any conclusions with regard to an air quality standard.

  2. Conceptual design of a novel CO2 capture process based on precipitating amino acid solvents

    NARCIS (Netherlands)

    Sanchez Fernandez, E.; Heffernan, K.; Ham, L.V. van der; Linders, M.J.G.; Eggink, E.; Schrama, F.N.H.; Brilman, D.W.F.; Goetheer, E.L.V.; Vlugt, T.J.H.

    2013-01-01

    Amino acid salt based solvents can be used for CO2 removal from flue gas in a conventional absorption-thermal desorption process. Recently, new process concepts have been developed based on the precipitation of the amino acid zwitterion species during the absorption of CO2. In this work, a new conce

  3. Symbiotic essential amino acids provisioning in the American cockroach, Periplaneta americana (Linnaeus) under various dietary conditions.

    Science.gov (United States)

    Ayayee, Paul A; Larsen, Thomas; Sabree, Zakee

    2016-01-01

    Insect gut microbes have been shown to provide nutrients such as essential amino acids (EAAs) to their hosts. How this symbiotic nutrient provisioning tracks with the host's demand is not well understood. In this study, we investigated microbial essential amino acid (EAA) provisioning in omnivorous American cockroaches (Periplaneta americana), fed low-quality (LQD) and comparatively higher-quality dog food (DF) diets using carbon stable isotope ratios of EAAs (δ (13)CEAA). We assessed non-dietary EAA input, quantified as isotopic offsets (Δ(13)C) between cockroach (δ (13)CCockroach EAA) and dietary (δ (13)CDietary EAA) EAAs, and subsequently determined biosynthetic origins of non-dietary EAAs in cockroaches using (13)C-fingerprinting with dietary and representative bacterial and fungal δ (13)CEAA. Investigation of biosynthetic origins of de novo non-dietary EAAs indicated bacterial origins of EAA in cockroach appendage samples, and a mixture of fungal and bacterial EAA origins in gut filtrate samples for both LQD and DF-fed groups. We attribute the bacteria-derived EAAs in cockroach appendages to provisioning by the fat body residing obligate endosymbiont, Blattabacterium and gut-residing bacteria. The mixed signatures of gut filtrate samples are attributed to the presence of unassimilated dietary, as well as gut microbial (bacterial and fungal) EAAs. This study highlights the potential impacts of dietary quality on symbiotic EAA provisioning and the need for further studies investigating the interplay between host EAA demands, host dietary quality and symbiotic EAA provisioning in response to dietary sufficiency or deficiency. PMID:27231663

  4. Detecting acid precipitation impacts on lake water quality

    Science.gov (United States)

    Loftis, Jim C.; Taylor, Charles H.

    1989-09-01

    The United States Environmental Protection Agency is planning to expand its long-term monitoring of lakes that are sensitive to acid deposition effects. Effective use of resources will require a careful definition of the statistical objectives of monitoring, a network design which balances spatial and temporal coverage, and a sound approach to data analysis. This study examines the monitoring objective of detecting trends in water quality for individual lakes and small groups of lakes. Appropriate methods of trend analysis are suggested, and the power of trend detection under seasonal (quarterly) sampling is compared to that of annual sampling. The effects of both temporal and spatial correlation on trend detection ability are described.

  5. Effects of simulated acidic precipitation on the colonization and ice nucleation activity of Pseudomonas syringae pv. syringae and Erwinia herbicola

    OpenAIRE

    Murray, Joseph Marshall

    1987-01-01

    Precipitation over the eastern United States has been increasing in acidity, particularly within the last three decades. The average annual pH of rain in this area is about 4.2. The foliar surface, or phylloplane, of soybean can be damaged by rain acidified to pH 2.9. Simulated acidic precipitation has an overall inhibitory influence on soil microbial processes. The effect acidic precipitation may have on epiphytic microorganisms has not been examined. Bacteria are amo...

  6. Fractionation of microimpurities during precipitation of basic zirconium sulfate out of nitric acid solutions

    International Nuclear Information System (INIS)

    A study was made on fractionation of microimpurities during precipitation of basic zirconium sulfate out of concentrated with respect to ZrO2 nitric acid solutions. Investigation into fractionation of Sc(3), Cr(3), Mn(2), Fe(3), Co(2), CU(2), Zn(2) and Y(3) microirpurities during hydrolytic precipitation of basic zirconium sulfate out of nitric acid solutions showed that a majority of microimpurities are characterized by high distribution factors and concentrate in mother liquor. Adsorption isotherms were constructed for Cu(2) and Fe(3) microimpurities. The assumption about the effect of microimpurity nature (ionic charge and radius, the electron structure) on precipitation mechanism was made on the base of obtained data

  7. Mercury Pollution of Soil—Crop System in Acid precipitation Area

    Institute of Scientific and Technical Information of China (English)

    MOUSHU-SEN; QINGCHANG-LE

    1995-01-01

    In acid precipitation area of Chongqing suburb the average of Hg in soil rose from 0.158mg/kg in 1984 to 0.20mg/kg in 1989,and Hg content of crops grown on these soils increased too.Both soil and vegetable Hg came mainly from power plant emission.which caused Hg and acid precipitiation pollution in environment and the Hg pollution of water,crops and milk in the area.

  8. PH BUFFERING IN FOREST SOIL ORGANIC HORIZONS: RELEVANCE TO ACID PRECIPITATION

    Science.gov (United States)

    Samples of organic surface horizons (Oi, Oe, Oa) from New York State forest soils were equilibrated with 0 to 20 cmol HNO3 Kg(-1) soil in the laboratory by a batch technique designed to simulate reactions of acid precipitation with forest floors. Each organic horizon retained a c...

  9. New process concepts for CO2 capture based on precipitating amino acids

    NARCIS (Netherlands)

    Sanchez-Fernandez, E.; Miguel Mercader, F. de; Misiak, K.; Ham, L.V. van der; Linders, M.J.G.; Goetheer, E.L.V.

    2013-01-01

    This work summarises the results of the design of novel separation processes for CO2 removal from flue gas based on precipitating amino acid solvents. The processes here described (DECAB, DECAB Plus and pH-swing) use a combination of enhanced CO2 absorption ( ) and / or enhanced CO2 desorption (base

  10. Metal chelate affinity precipitation: purification of BSA using poly(N-vinylcaprolactam-co-methacrylic acid) copolymers.

    Science.gov (United States)

    Ling, Yuan-Qing; Nie, Hua-Li; Brandford-White, Christopher; Williams, Gareth R; Zhu, Li-Min

    2012-06-01

    This investigation involves the metal chelate affinity precipitation of bovine serum albumin (BSA) using a copper ion loaded thermo-sensitive copolymer. The copolymer of N-vinylcaprolactam with methacrylic acid PNVCL-co-MAA was synthesized by free radical polymerization in aqueous solution, and Cu(II) ions were attached to provide affinity properties for BSA. A maximum loading of 48.1mg Cu(2+) per gram of polymer was attained. The influence of pH, temperature, BSA and NaCl concentrations on BSA precipitation and of pH, ethylenediaminetetraacetic acid (EDTA) and NaCl concentrations on elution were systematically probed. The optimum conditions for BSA precipitation occurred when pH, temperature and BSA concentration were 6.0, 10°C and 1.0 mg/ml, respectively and the most favorable elution conditions were at pH 4.0, with 0.2M NaCl and 0.06 M EDTA. The maximum amounts of BSA precipitation and elution were 37.5 and 33.7 mg BSA/g polymer, respectively. It proved possible to perform multiple precipitation/elution cycles with a minimal loss of polymer efficacy. The results show that PNVCL-co-MAA is a suitable matrix for the purification of target proteins from unfractionated materials.

  11. Acid precipitation and other possible sources for acidification of rivers and lakes

    Energy Technology Data Exchange (ETDEWEB)

    Seip, H.M.; Tollan, A.

    1978-01-01

    The trends in the recent acidification of rivers and lakes in South Norway are reviewed, and the evidence for a causal relationship between acid precipitation and acidification of surface water is critically examined. Results from regional surveys, studies in small catchment areas and from percolation experiments are presented. Several sources may contribute to the acidification. However, changes in the composition of the precipitation during the recent decades, mainly because of increased combustion of fossil fuels, seem to be a dominant cause at least in some of the most affected areas.

  12. Struvite Precipitation for Ammonia Nitrogen Removal in 7-Aminocephalosporanic Acid Wastewater

    Directory of Open Access Journals (Sweden)

    Erhong Duan

    2012-02-01

    Full Text Available 7-Aminocephalosporanic acid wastewater usually contains high concentrations of ammonium (NH4+-N, which is known to inhibit nitrification during biological treatment processes. Chemical precipitation is a useful technology to remove ammonium from wastewater. In this paper, the removal of ammonium from 7-aminocephalosporanic acid wastewater was studied. The optimum pH, molar ratio, and various chemical compositions of magnesium ammonium phosphate (MAP precipitation were investigated. The results indicated that ammonium in 7-aminocephalosporanic acid wastewater could be removed at an optimum pH of 9. The Mg2+:NH4+-N:PO43−-P molar ratio was readily controlled at a ratio of 1:1:1.1 to both effectively remove ammonium and avoid creating a higher concentration of PO43−-P in the effluent. MgCl2·6H2O + 85% H3PO4 was the most efficient combination for NH4+-N removal. Furthermore, the lowest concentration of the residual PO43−-P was obtained with the same combination. Struvite precipitation could be considered an effective technology for the NH4+-N removal from the 7-aminocephalosporanic acid wastewater.

  13. Optimization of the precipitation of clavulanic acid from fermented broth using t-octylamine as intermediate

    Directory of Open Access Journals (Sweden)

    D. B. Hirata

    2013-06-01

    Full Text Available This work describes the use of clavulanic acid (CA precipitation as the final step in the process of purification of CA from fermentation broth as an alternative to conventional methods employed traditionally. The purpose of this study was to use a stable intermediate (t-octylamine between the conversion of CA to its salt form (potassium clavulanate, thereby enabling the resulting intermediate (amine salt of clavulanic acid to improve the purification process and maintain the stability of the resulting potassium clavulanate. To this end, response surface methodology was employed to optimize the precipitation step. For the first reaction, five temperatures (6.6 to 23.4 ºC, concentrations of clavulanic acid in organic solvent (6.6 to 23.4 mg/mL and t-octylamine inflow rates (0.33 to 1.17 drop/min were selected based on a central composite rotatable design (CCRD. For the second reaction, five temperatures (11.6 to 28.4 ºC, concentrations of clavulanic acid amine salt in organic solvent (8.2 to 41.8 mg/mL and concentrations of potassium 2-ethylhexanoate (0.2 to 1.2 molar were also selected using CCRD. From these results, precipitation conditions were selected and applied to the purification of CA from the fermentation broth, obtaining a yield of 72.37%.

  14. First studies on a new concept for amino acid provision through B. subtilis in situ valine production in young pigs

    DEFF Research Database (Denmark)

    Nørgaard, J.V.; Canibe, N.; Nielsen, B.;

    2012-01-01

    Supplementation of crystalline amino acids is common in diets for piglets. The purpose of the present experiment was to conduct a study on an alternative amino acid provision by means of feeding piglets spores of a B. subtilis strain known to overproduce Val when cultured in vitro. Seventeen indi...

  15. Morphologies, mechanical properties and thermal stability of poly(lactic acid) toughened by precipitated barium sulfate

    Science.gov (United States)

    Yang, Jinian; Wang, Chuang; Shao, Kaiyun; Ding, Guoxin; Tao, Yulun; Zhu, Jinbo

    2015-11-01

    Poly(lactic acid) (PLA)-based composites were prepared by blending PLA with precipitated barium sulfate (BaSO4) modified with stearic acid. The morphologies, mechanical properties and thermal stability of samples with increased mass fraction of BaSO4 were investigated. Results showed that PLA was toughened and reinforced simultaneously by incorporation of precipitated BaSO4 particles. The highest impact toughness and elongation at break were both achieved at 15% BaSO4, while the elastic modulus increased monotonically with increasing BaSO4 loading. Little effect of BaSO4 on the thermal behavior of PLA was observed in the present case. However, the thermal stability of PLA/BaSO4 composites at high temperature was enhanced.

  16. Economic valuation of acidic deposition damages: Preliminary results from the 1985 NAPAP [National Acid Precipitation Assessment Program] damage assessment

    International Nuclear Information System (INIS)

    This paper identifies methods used to evaluate the economic damages of acid deposition in the 1985 Damage Assessment being coordinated by the National Acid Precipitation Program. It also presents the preliminary estimates of economic damages for the Assessment. Economic damages are estimated for four effect areas: commercial agriculture and forests, recreational fishing and selected types of materials. In all but the last area, methods are used which incorporate the behavioral responses of individuals and firms or simulated physical damages to resources at risk. The preliminary nature of the estimated damages in each area is emphasized. Over all, the damage estimates should be interpreted with caution. 44 refs., 6 figs., 5 tabs

  17. Fabrication and characterization of magnetic ferrofluids by the co-precipitation way using diglycolic acid

    Energy Technology Data Exchange (ETDEWEB)

    Jagminas, Arunas, E-mail: jagmin@ktl.mii.lt; Kurtinaitiene, Marija; Mazeika, Kestutis [State Research Institute Center for Physical Sciences, and Technology (Lithuania); Rotomskis, Ricardas [Vilnius University, Institute of Oncology (Lithuania); Niaura, Gediminas; Selskis, Algirdas [State Research Institute Center for Physical Sciences, and Technology (Lithuania)

    2011-09-15

    Developing of a simple method for the fabrication of superparamagnetic iron oxide nanoparticles (Nps) is still a challenge for materials scientists. This work reveals a way to fabricate especially stable ferrofluids from spherical Nps of magnetite using the co-precipitation method, for which a new (diglycolic acid) stabilizer was applied. The Nps of the average size of {approx}7.4-16.5 nm were characterized by means of high resolution transmission electron microscopy (HRTEM), atomic force microscopy (AFM), selective area electron diffraction (SAED), Raman, FTIR and Moessbauer spectroscopy. The stabilization effect of the diglycolic acid for the growth of superparamagnetic Nps growth was discussed on the basis of experimental results.

  18. Potential health implications for acid precipitation, corrosion, and metals contamination of drinking water.

    Science.gov (United States)

    Sharpe, W E; DeWalle, D R

    1985-11-01

    Potential health effects of drinking water quality changes caused by acid precipitation are presented. Several different types of water supply are discussed and their roles in modifying acid rain impacts on drinking water are explained. Sources of metals contamination in surface water supplies are enumerated. The authors present some results from their research into acid rain impacts on roof-catchment cisterns, small surface water supplies, and lead mobilization in acid soils. A good correlation was obtained between cistern water corrosivity as measured by the Ryznar Index (RI) values and standing tapwater copper concentrations. However, lead concentrations in tapwater did not correlate well with cistern water RI. A modified linear regression model that accounted for Ryznar Index change during storage in vinyl-lined cisterns was used to predict the Ryznar Index value at a copper concentration of 1000 micrograms/L. The predicted RI was greater than the RI of precipitation with a pH of 5.3, indicating that anthropogenically acidified precipitation may result in cistern tapwater copper concentrations in excess of the 1000 micrograms/L suggested drinking water limit. Good correlations between tapwater Ryznar Index and tapwater copper and lead concentrations were not obtained for the small surface water supply. Aluminum concentrations in reservoir water were similar to those in stream source water. Limited data were also presented that indicated lead was present in acid forest soil leachate and streams draining such soils in relatively small concentrations. Where appropriate, recommendations for future research are included with the discussions of research results. PMID:4076096

  19. Colloidal precipitates related to Acid Mine Drainage: bacterial diversity and micro fungi-heavy metal interactions

    Science.gov (United States)

    Lucchetti, G.; Carbone, C.; Consani, S.; Zotti, M.; Di Piazza, S.; Pozzolini, M.; Giovine, M.

    2015-12-01

    In Acid Mine Drainage (AMD) settings colloidal precipitates control the mobility of Potential Toxic Elements (PTEs). Mineral-contaminant relationships (i.e. adsorption, ion-exchange, desorption) are rarely pure abiotic processes. Microbes, mainly bacteria and microfungi, can catalyze several reactions modifying the element speciation, as well as the bioavailability of inorganic pollutants. Soil, sediments, and waters heavily polluted with PTEs through AMD processes are a potential reservoir of extremophile bacteria and fungi exploitable for biotechnological purposes. Two different AMD related colloids, an ochraceous precipitate (deposited in weakly acidic conditions, composed by nanocrystalline goethite) and a greenish-blue precipitate (deposited at near-neutral pH, composed by allophane + woodwardite) were sampled. The aims of this work were to a) characterize the mycobiota present in these colloidal minerals by evaluating the presence of alive fungal propagules and extracting bacteria DNA; b) verify the fungal strains tolerance, and bioaccumulation capability on greenish-blue and ZnSO4 enriched media; c) evaluate potential impact of bacteria in the system geochemistry. The preliminary results show an interesting and selected mycobiota able to survive under unfavourable environmental conditions. A significant number of fungal strains were isolated in pure culture. Among them, species belonging to Penicillium and Trichoderma genera were tested on both greenish-blue and ZnSO4 enriched media. The results show a significant tolerance and bioaccumulation capability to some PTEs. The same colloidal precipitates were processed to extract bacteria DNA by using a specific procedure developed for sediments. The results give a good yield of nucleic acids and a positive PCR amplification of 16S rDNA accomplished the first step for future metagenomic analyses.

  20. The influence of organic compounds on the development of precipitation acidity in maritime clouds

    Directory of Open Access Journals (Sweden)

    L. Alfonso

    2004-01-01

    Full Text Available In order to estimate the anthropogenic influence of gas and aerosol emissions from the Petroleum Industry in maritime zones with clouds of small vertical extent, a numerical 1-D Eulerian cloud-chemical model with detailed microphysics (Alfonso and Raga, 2002 is used to simulate the influence of water soluble organic compounds (WSOC and organic+inorganic gas emissions on cloud development. Following Mircea et al. (2002, we tested the sensitivity of the cloud and precipitation development in the classical inorganic case (CIC and the inorganic+organic case (IOC with respect to CCN compositions. The results indicate an increase in the droplet concentration for the IOC, and a delay in the development of precipitation. The pH spectral evolution was studied during both the development and precipitation stages. The influence of the diffusion of formic acid and its generation by oxidation of hydrated formaldehyde in the aqueous phase result in a reduction in the pH of precipitation in the range between 0.05 and 0.15 pH units (from 1 to 3% for the high ambient SO2 concentration (20 ppb and between 0.2-0.5 pH units (from 4 to 10% for the low ambient SO2 concentration (1 ppb case.

  1. High-molecular-weight polymers for protein crystallization: poly-γ-glutamic acid-based precipitants

    International Nuclear Information System (INIS)

    High-molecular-weight poly-γ-glutamic acid-based polymers have been synthesized, tested and adopted for protein crystallization. Protein crystallization has been revolutionized by the introduction of high-throughput technologies, which have led to a speeding up of the process while simultaneously reducing the amount of protein sample necessary. Nonetheless, the chemistry dimension of protein crystallization has remained relatively undeveloped. Most crystallization screens are based on the same set of precipitants. To address this shortcoming, the development of new protein precipitants based on poly-γ-glutamic acid (PGA) polymers with different molecular-weight ranges is reported here: PGA-LM (low molecular weight) of ∼400 kDa and PGA-HM (high molecular weight) of >1000 kDa. It is also demonstrated that protein precipitants can be expanded further to polymers with much higher molecular weight than those that are currently in use. Furthermore, the modification of PGA-like polymers by covalent attachments of glucosamine substantially improved their solubility without affecting their crystallization properties. Some preliminary PGA-based screens are presented here

  2. Recovery of molybdenum, nickel and cobalt by precipitation from the acidic leachate of a mineral sludge.

    Science.gov (United States)

    Vemic, M; Bordas, F; Comte, S; Guibaud, G; Lens, P N L; van Hullebusch, E D

    2016-09-01

    The objective of this study was to investigate the recovery potential of molybdenum (Mo), nickel (Ni) and cobalt (Co) from synthetic and real acidic leachate of a mineral sludge from a metal recycling plant by sulfide precipitation. The operational parameters (metal sulfide (M/S) ratio 0.1-1, agitation speed 0-100 rpm, contact time 15-120 min and pH 1-5) were optimized in batch conditions on synthetic metal leachate (0.5 M HNO3, Mo = 101.6 mg L(-1), Ni = 70.8 mg L(-1), Co = 27.1 mg L(-1)) with a 0.1 M Na2S solution. Additionally, recovery of the target metals was theoretically simulated with a chemical equilibrium model (Visual MINTEQ 3.0). The optimized Na2S precipitation of metals from the synthetic leachate resulted in the potential selective recovery of Mo at pH 1 (98% by modeling, 95% experimental), after simultaneous precipitation of Ni and Co as sulfide at pH 4 (100% by modeling, 98% experimental). Metal precipitation from the real leachate (18 M H2SO4, Mo = 10,160 mg L(-1), Ni = 7,080 mg L(-1), Co = 2,710 mg L(-1)) was performed with 1 M Na2S, and resulted in a maximal Mo recovery at pH 2 (50%), while maximal recoveries of Ni and Co were observed at pH 4 (56% and 60%, respectively). Real leachate gave a lower metals recovery efficiency compared with synthetic leachate, which can be attributed to changes in the pH, nature of leachant, co-precipitation of Zn and competition for S(2-) ions. PMID:26824137

  3. Precipitation of pertechnetate ion from nitric acid solutions using complexes of copper(II) with heterocyclic N-donor ligands

    International Nuclear Information System (INIS)

    The TcO4- precipitation with organic complexes of Cu(II) from nitric acid solutions was studied. Complex Cu(phen)3(NO3)2 was chosen as the optimal precipitant. The conditions for maximum Tc precipitation of 95 ± 3 % were determined. It was shown the possibility to obtain metal-Tc alloys by thermal treatment of the precipitates. As found, the addition of the fusible metal (Sn) to the sediment was required to receive appropriate matrix. Cu-Tc-Sn matrix was tested for Tc leaching. (author)

  4. Oxidative Precipitation of Manganese from Acid Mine Drainage by Potassium Permanganate

    OpenAIRE

    Regeane M. Freitas; Perilli, Thomaz A. G.; Ladeira, Ana Claudia Q.

    2013-01-01

    Although oxidative precipitation by potassium permanganate is a widely recognised process for manganese removal, research dealing with highly contaminated acid mine drainage (AMD) has yet to be performed. The present study investigated the efficiency of KMnO4 in removing manganese from AMD effluents. Samples of AMD that originated from inactive uranium mine in Brazil were chemically characterised and treated by KMnO4 at pH 3.0, 5.0, and 7.0. Analyses by Raman spectroscopy and geochemical mode...

  5. Technical and economical assessment of formic acid to recycle phosphorus from pig slurry by a combined acidification-precipitation process.

    Science.gov (United States)

    Daumer, M-L; Picard, S; Saint-Cast, P; Dabert, P

    2010-08-15

    Dissolution by acidification followed by a liquid/solid separation and precipitation of phosphorus from the liquid phase is one possibility to recycle phosphorus from livestock effluents. To avoid increase of effluent salinity by using mineral acids in the recycling process, the efficiency of two organic acids, formic and acetic acid, in dissolving the mineral phosphorus from piggery wastewater was compared. The amount of formic acid needed to dissolve the phosphorus was reduced three fold, compared to acetic acid. The amount of magnesium oxide needed for further precipitation was decreased by two with formic acid. Neither the carbon load nor the effluent salinity was significantly increased by using formic acid. An economical comparison was performed for the chemical recycling process (mineral fertilizer) vs. centrifugation (organic fertilizer) considering the centrifugation and the mineral fertilizers sold in the market. After optimisation of the process, the product could be economically competitive with mineral fertilizer as superphosphate in less than 10 years. PMID:20471746

  6. National Acid Precipitation Assessment Program Report to Congress: An Integrated Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Uhart, M.; et al,

    2005-08-01

    Under Title IX of the 1990 Clean Air Act Amendments, Congress reauthorized the National Acid Precipitation Assessment Program (NAPAP) to continue coordinating acid rain research and monitoring, as it had done during the previous decade, and to provide Congress with periodic reports. In particular, Congress asked NAPAP to assess all available data and information to answer two questions: (1) What are the costs, benefits, and effectiveness of Title IV? This question addresses the costs and economic impacts of complying with the Acid Rain Program as well as benefit analyses associated with the various human health and welfare effects, including reduced visibility, damages to materials and cultural resources, and effects on ecosystems. (2) What reductions in deposition rates are needed to prevent adverse ecological effects? This complex questions addresses ecological systems and the deposition levels at which they experience harmful effects. The results of the assessment of the effects of Title IV and of the relationship between acid deposition rates and ecological effects were to be reported to Congress quadrennially, beginning with the 1996 report to Congress. The objective of this Report is to address the two main questions posed by Congress and fully communicate the results of the assessment to decision-makers. Given the primary audience, most of this report is not written as a technical document, although information supporting the conclusions is provided along with references.

  7. Acid Rain Examination and Chemical Composition of Atmospheric Precipitation in Tehran, Iran

    Directory of Open Access Journals (Sweden)

    Mohsen Saeedi

    2012-01-01

    Full Text Available Air pollution is one of the most important environmental problems in metropolitan cities like Tehran. Rain and snow, as natural events, may dissolve and absorb contaminants of the air and direct them onto the land or surface waters which become polluted. In the present study, precipitation samples were collected from an urbanized area of Tehran. They were analyzed for NO3-, PO43-, SO42-, pH, turbidity, Electrical Conductivity (EC, Cu, Fe, Zn, Pb, Ni, Cr, and Al. We demonstrate that snow samples were often more polluted and had lower pH than those from the rain, possibly as an effect of adsorption capability of snow flakes. Volume weighted average concentrations were calculated and compared with some other studies. Results revealed that Tehran's precipitations are much more polluted than those reported from other metropolitan cities. Cluster analysis revealed that studied parameters such as metals and acidity originated from the same sources, such as fuel combustion in residential and transportation sectors of Tehran.

  8. Influence of some agricultural practices on the soil acidification in acid precipitation areas

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Both acid precipitation and unreasonable agricultural practices are notorious artificial factors resulting in soil acidification. To sort out reasonable agricultural practices favorable to abating soil acidification, the task of this study was directed to a long-term field trial in Chongqing, during which chemical fertilizer, organic fertilizer were applied to different crop rotations and the soil pH value was measured. The results indicated that all treatments decreased pH value in the 0 to 20 cm soil layer after ten years. Problems were more serious when chlorine-containing fertilizer, excessive chemical fertilizer and mixed fertilizer were applied. It is demonstrated that balance rates of N, P and K fertilizers, application of muck in field are advantageous to abating soil acidification. Oil plants affect soil acidification more than cereal in different crop rotation.

  9. A MORPHOLOGICAL STUDY OF POLY(DIVINYLBENZENE-co-ACRYLIC ACID) IN CROSSLINKING PRECIPITATION POLYMERIZATION

    Institute of Scientific and Technical Information of China (English)

    Feng Bai; Xin-lin Yang; Wen-qiang Huang

    2006-01-01

    Divinylbenzene-80 (DVB-80) and polar monomer acrylic acid (AA) having hydrogen bonding at a total monomer loading of 5 vol% were precipitated-copolymerized in a variety of organic solvents with 2,2'-azobis(isobutyronitrile) (AIBN) as initiator. The experiments were investigated from a two-dimensional matrix, i.e., the actual crosslinking degree of DVB varying from 0 to 80% and the solvent composition varying from 0 to 100% of toluene mixture with acetonitrile, when the mixture of acetonitrile and toluene was used as the reaction solvent. Under various reaction conditions, six distinct morphologies including soluble polymers, swellable microgels, coagulum, irregular microparticles, and nano-/micrometer microspheres were formed and the structures of these polymer architectures were described. A morphological map was utilized to discuss the effects of both crosslinking degree of DVB and composition of solvent on the transitions between morphology domains. The results demonstrated that the microspheres are formed by an internal contraction due to the marginal solvency of the continuous phase and the crosslinking of the polymer network through the covalent bonding from DVB as well as the interchain hydrogen-bonding between the carboxylic acid units.

  10. Molecularly imprinted polymer for caffeic acid by precipitation polymerization and its application to extraction of caffeic acid and chlorogenic acid from Eucommia ulmodies leaves.

    Science.gov (United States)

    Miura, Chitose; Matsunaga, Hisami; Haginaka, Jun

    2016-08-01

    Molecularly imprinted polymers (MIPs) for caffeic acid (CA) were prepared using 4-vinylpyridine and methacrylamide (MAM) as functional monomers, divinylbenzene as a crosslinker and acetonitrile-toluene (3:1, v/v) as a porogen by precipitation polymerization. The use of MAM as the co-monomer resulted in the formation of microsphere MIPs and non-imprinted polymers (NIPs) with ca. 3- and 5-μm particle diameters, respectively. Binding experiments and Scatchard analyses revealed that the binding capacity and affinity of the MIP to CA are higher than those of the NIP. The retention and molecular-recognition properties of the prepared MIPs were evaluated using water-acetonitrile and sodium phosphate buffer-acetonitrile as mobile phases in hydrophilic interaction chromatography (HILIC) and reversed-phase chromatography, respectively. In HILIC mode, the MIP showed higher molecular-recognition ability for CA than in reversed-phase mode. In addition to shape recognition, hydrophilic interactions seem to work for the recognition of CA on the MIP in HILIC mode, while hydrogen bonding and hydrophobic interactions seem to work for the recognition of CA in reversed-phase mode. The MIP had a specific molecular-recognition ability for CA in HILIC mode, while other structurally related compounds, such as chlorogenic acid (CGA), gallic acid, protocatechuic acid and vanillic acid, could not be recognized by the MIP. Furthermore, the MIP was successfully applied for extraction of CA and CGA in the leaves of Eucommia ulmodies in HILIC mode. PMID:26776340

  11. Recovery of Vanadium from H2SO4-HF Acidic Leaching Solution of Black Shale by Solvent Extraction and Precipitation

    Directory of Open Access Journals (Sweden)

    Xingbin Li

    2016-03-01

    Full Text Available The recovery of vanadium from sulfuric and hydrofluoric mixed acid solutions generated by the direct leaching of black shale was investigated using solvent extraction and precipitation methods. The process consisted of reduction, solvent extraction, and stripping, followed by precipitation and calcination to yield vanadium pentoxide. The influence of various operating parameters on the extraction and recovery of vanadium was studied. Vanadium (IV was selectively extracted using a mixture of 10% (v/v di(2-ethylhexylphosphoric acid and 5% (v/v tri-n-butylphosphate in sulfonated kerosene. Using six extraction and five stripping stages, the extraction efficiency for vanadium was 96.7% and the stripping efficiency was 99.7%. V2O5 with a purity of 99.52% was obtained by oxidation of the loaded strip solution and precipitation of ammonium polyvanadate at pH 1.8 to 2.2, followed by calcination of the dried precipitate at 550 °C for 2 h. It was concluded that the combination of solvent extraction and precipitation is an efficient method for the recovery of vanadium from a multi-element leach solution generated from black shale.

  12. Comparison of Four Strong Acids on the Precipitation Potential of Gypsum in Brines During Distillation of Pretreated, Augmented Urine

    Science.gov (United States)

    Muirhead, Dean; Carrier, Christopher

    2012-01-01

    In this study, three different mineral acids were substituted for sulfuric acid (H2SO4) in the urine stabilizer solution to eliminate the excess of sulfate ions in pretreated urine and assess the impact on maximum water recovery to avoid precipitation of minerals during distillation. The study evaluated replacing 98% sulfuric acid with 85% phosphoric acid (H3PO4), 37% hydrochloric acid (HCl), or 70% nitric acid (HNO3). The effect of lowering the oxidizer concentration in the pretreatment formulation also was studied. This paper summarizes the test results, defines candidate formulations for further study, and specifies the injection masses required to stabilize urine and minimize the risk of mineral precipitation during distillation. In the first test with a brine ersatz acidified with different acids, the solubility of calcium in gypsum saturated solutions was measured. The solubility of gypsum was doubled in the brines acidified with the alternative acids compared to sulfuric acid. In a second series of tests, the alternative acid pretreatment concentrations were effective at preventing precipitation of gypsum and other minerals up to 85% water recovery from 95th-percentile pretreated, augmented urine. Based on test results, phosphoric acid is recommended as the safest alternative to sulfuric acid. It also is recommended that the injected mass concentration of chromium trioxide solution be reduced by 75% to minimize liquid resupply mass by about 50%, reduce toxicity of brines, and reduce the concentration of organic acids in distillate. The new stabilizer solution formulations and required doses to stabilize urine and prevent precipitation of minerals up to 85% water recovery are given. The formulations in this study were tested on a limited number of artificially augmented urine batches collected from employees at the Johnson Space Center (JSC). This study successfully demonstrated that the desired physical and chemical stability of pretreated urine and brines

  13. Precipitation of arsenic sulphide from acidic water in a fixed-film bioreactor.

    Science.gov (United States)

    Battaglia-Brunet, Fabienne; Crouzet, Catherine; Burnol, André; Coulon, Stéphanie; Morin, Dominique; Joulian, Catherine

    2012-08-01

    Arsenic (As) is a toxic element frequently present in acid mine waters and effluents. Precipitation of trivalent arsenic sulphide in sulphate-reducing conditions at low pH has been studied with the aim of removing this hazardous element in a waste product with high As content. To achieve this, a 400m L fixed-film column bioreactor was fed continuously with a synthetic solution containing 100mg L(-1) As(V), glycerol and/or hydrogen, at pH values between 2.7 and 5. The highest global As removal rate obtained during these experiments was close to 2.5mg L(-1)h(-1). A switch from glycerol to hydrogen when the biofilm was mature induced an abrupt increase in the sulphate-reducing activity, resulting in a dramatic mobilisation of arsenic due to the formation of soluble thioarsenic complexes. A new analytical method, based on ionic chromatography, was used to evaluate the proportion of As present as thioarsenic complexes in the bioreactor. Profiles of pH, total As and sulphate concentrations suggest that As removal efficiency was linked to solubility of orpiment (As(2)S(3)) depending on pH conditions. Molecular fingerprints revealed fairly homogeneous bacterial colonisation throughout the reactor. The bacterial community was diverse and included fermenting bacteria and Desulfosporosinus-like sulphate-reducing bacteria. arrA genes, involved in dissimilatory reduction of As(V), were found and the retrieved sequences suggested that As(V) was reduced by a Desulfosporosinus-like organism. This study was the first to show that As can be removed by bioprecipitation of orpiment from acidic solution containing up to 100mg L(-1) As(V) in a bioreactor.

  14. Oxidative Precipitation of Manganese from Acid Mine Drainage by Potassium Permanganate

    Directory of Open Access Journals (Sweden)

    Regeane M. Freitas

    2013-01-01

    Full Text Available Although oxidative precipitation by potassium permanganate is a widely recognised process for manganese removal, research dealing with highly contaminated acid mine drainage (AMD has yet to be performed. The present study investigated the efficiency of KMnO4 in removing manganese from AMD effluents. Samples of AMD that originated from inactive uranium mine in Brazil were chemically characterised and treated by KMnO4 at pH 3.0, 5.0, and 7.0. Analyses by Raman spectroscopy and geochemical modelling using PHREEQC code were employed to assess solid phases. Results indicated that the manganese was rapidly oxidised by KMnO4 in a process enhanced at higher pH. The greatest removal, that is, 99%, occurred at pH 7.0, when treated waters presented manganese levels as low as 1.0 mg/L, the limit established by the Brazilian legislation. Birnessite (MnO2, hausmannite (Mn3O4, and manganite (MnOOH were detected by Raman spectroscopy. These phases were consistently identified by the geochemical model, which also predicted phases containing iron, uranium, manganese, and aluminium during the correction of the pH as well as bixbyite (Mn2O3, nsutite (MnO2, pyrolusite (MnO2, and fluorite (CaF2 following the KMnO4 addition.

  15. On the Relation between Natural and Enforced Syneresis of Acidic Precipitated Silica

    Directory of Open Access Journals (Sweden)

    Sebastian Wilhelm

    2014-11-01

    Full Text Available Silica in industrial production processes is precipitated by mixing an acid and an inorganic precursor. In this aqueous solution, silica particles form due to a polymerization reaction and agglomeration and, finally, build a gel. Thereafter, the reaction continues, and the gel network shrinks with the expulsion of the enclosed pore liquid. This slow process is known as “natural syneresis” and strongly affects the product properties, such as the agglomerate size, specific surface or porosity of the silica produced. In order to investigate the influence of process parameters, such as temperature, pH or ionic strength, on the shrinkage in shorter time-scales, we propose an acceleration of this process and define it as “enforced syneresis”. The acceleration is performed by applying a mechanical external force to the gel by means of a plunger and measuring the shrinkage behavior under these conditions. Thereby, the conceptual idea is the prediction of the shrinkage due to natural syneresis based on the results of enforced syneresis. We are now able to predict the natural syneresis behavior from enforced syneresis data by the development of a correlative model. Using this prediction model, we can show the influence of temperature on the maximum shrinkage and on its rate in a significantly shorter time of about 12 h instead of several days.

  16. Tartaric acid-assisted co-precipitation synthesis of Er3+-doped Lu2O3 nanopowders

    Institute of Scientific and Technical Information of China (English)

    Neng Li Wang; Xi Yan Zhang; Peng He Wang

    2012-01-01

    Erbium-doped lutetia nanopowders were synthesized by a novel co-precipitation method using tartaric acid as precipitant.The properties of the samples were investigated by Fourier transform infrared spectroscopy (FTIR),X-ray diffraction (XRD),TG-DSC,field emission scanning electron microscopy (FE-SEM),and upeonversion luminescence analysis.Pure cubic Lu2O3 nanopowders were directly obtained when the precursor was calcined at 800 ℃ for 2 h,the samples showed strong upconversion luminescence under excitation of 980 nm laser diode.

  17. Particle size tailoring of ursolic acid nanosuspensions for improved anticancer activity by controlled antisolvent precipitation.

    Science.gov (United States)

    Wang, Yancai; Song, Ju; Chow, Shing Fung; Chow, Albert H L; Zheng, Ying

    2015-10-15

    The present study was aimed at tailoring the particle size of ursolic acid (UA) nanosuspension for improved anticancer activity. UA nanosuspensions were prepared by antisolvent precipitation using a four-stream multi-inlet vortex mixer (MIVM) under defined conditions of varying solvent composition, drug feeding concentration or stream flow rate. The resulting products were characterized for particle size and polydispersity. Two of the UA nanosuspensions with mean particle sizes of 100 and 300 nm were further assessed for their in-vitro activity against MCF-7 breast cancer cells using fluorescence microscopy with 4',6-diamidino-2-phenylindole (DAPI) staining, as well as flow cytometry with propidium (PI) staining and with double staining by fluorescein isothiocyanate. It was revealed that the solvent composition, drug feeding concentration and stream flow rate were critical parameters for particle size control of the UA nanosuspensions generated with the MIVM. Specifically, decreasing the UA feeding concentration or increasing the stream flow rate or ethanol content resulted in a reduction of particle size. Excellent reproducibility for nanosuspension production was demonstrated for the 100 and 300 nm UA preparations with a deviation of not more than 5% in particle size from the mean value of three independent batches. Fluorescence microscopy and flow cytometry revealed that these two different sized UA nanosuspensions, particularly the 300 nm sample, exhibited a higher anti-proliferation activity against the MCF-7 cells and afforded a larger population of these cells in both early and late apoptotic phases. In conclusion, MIVM is a robust and pragmatic tool for tailoring the particle size of the UA nanosuspension. Particle size appears to be a critical determinant of the anticancer activity of the UA nanoparticles.

  18. The effects of acid precipitation runoff episodes on reservoir and tapwater quality in an Appalachian Mountain water supply.

    OpenAIRE

    Sharpe, W E; DeWalle, D R

    1990-01-01

    The aluminum concentration and Ryznar Index increased and the pH decreased in a small Appalachian water supply reservoir following acid precipitation runoff episodes. Concomitant increases in tapwater aluminum and decreases in tapwater pH were also observed at two homes in the water distribution system. Lead concentrations in the tapwater of one home frequently exceeded recommended levels, although spatial and temporal variation in tapwater copper and lead concentrations was considerable. Sin...

  19. Two-stage precipitation process of iron and arsenic from acid leaching solutions

    Institute of Scientific and Technical Information of China (English)

    N.J.BOLIN; J.E.SUNDKVIST

    2008-01-01

    A leaching process for base metals recovery often generates considerable amounts of impurities such as iron and arsenic into the solution.It is a challenge to separate the non-valuable metals into manageable and stable waste products for final disposal,without loosing the valuable constituents.Boliden Mineral AB has patented a two-stage precipitation process that gives a very clean iron-arsenic precipitate by a minimum of coprecipitation of base metals.The obtained product shows to have good sedimentation and filtration properties,which makes it easy to recover the iron-arsenic depleted solution by filtration and washing of the precipitate.Continuos bench scale tests have been done,showing the excellent results achieved by the two-stage precipitation process.

  20. The influence of calcium, magnesium, phosphorus and silica in vanadium precipitation in acidic sulfate solutions

    International Nuclear Information System (INIS)

    The experimental research work was carried out in accordance with the Factorial Design Statistical Method to evaluate and analyze the influence of calcium, magnesium, silica and phosphorus on the precipitation of vanadates. precipitation was performed by neutralization with H2 SO4 of alkaline aqueous solutions containing vanadium pentoxide (V2 O5) at 60 ± 2 deg C. The experimental responses measured were percent of vanadium recovery and vanadium pentoxide content in the precipitate. These impurities are considered representative of those present in a leach liquor from the ore obtained at Campo Alegre de Lourdes (Brazil). The operational variables in this work were used optimum conditions as determined by the statistical approach. Among the impurities under study, phosphorus exhibited the highest negative influence on the experimental responses. Phosphorus diminished the percent of vanadium recovered from 98.9 to 34.5 and the vanadium oxide content in the precipitate from 91.2% to 39.3%. (author)

  1. Precipitation regime for selected amino acid salts for CO2 capture from flue gases

    NARCIS (Netherlands)

    Majchrowicz, Magdalena E.; Brilman, D.W.F. (Wim); Groeneveld, Michiel J.

    2009-01-01

    The tendency of alkaline (sodium, potassium and lithium) salts of taurine, β-alanine, sarcosine and L-proline to form precipitates under varying operational conditions of CO2 absorption has been investigated. CO2 absorption experiments have been performed at 293.15 and 313.15 K, at partial pressures

  2. The influence of calcium, magnesium, phosphorus and silica in vanadium precipitation in acidic sulfate solutions

    Energy Technology Data Exchange (ETDEWEB)

    Martins, A.H. [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Dept. de Engenharia Metalurgica e de Materiais. E-mail: ahmartin@demet.ufmg.br

    2000-06-01

    The experimental research work was carried out in accordance with the Factorial Design Statistical Method to evaluate and analyze the influence of calcium, magnesium, silica and phosphorus on the precipitation of vanadates. precipitation was performed by neutralization with H{sub 2} SO{sub 4} of alkaline aqueous solutions containing vanadium pentoxide (V{sub 2} O{sub 5}) at 60 {+-} 2 deg C. The experimental responses measured were percent of vanadium recovery and vanadium pentoxide content in the precipitate. These impurities are considered representative of those present in a leach liquor from the ore obtained at Campo Alegre de Lourdes (Brazil). The operational variables in this work were used optimum conditions as determined by the statistical approach. Among the impurities under study, phosphorus exhibited the highest negative influence on the experimental responses. Phosphorus diminished the percent of vanadium recovered from 98.9 to 34.5 and the vanadium oxide content in the precipitate from 91.2% to 39.3%. (author)

  3. The influence of calcium, magnesium, phosphorus and silica on vanadium precipitation in acidic sulfate solutions

    Directory of Open Access Journals (Sweden)

    Martins A. H.

    2000-01-01

    Full Text Available The experimental research work was carried out in accordance with the Factorial Design Statistical Method to evaluate and analyze the influence of calcium, magnesium, silica and phosphorus on the precipitation of vanadates. Precipitation was performed by neutralization with H2SO4 of alkaline aqueous solutions containing vanadium pentoxide (V2O5 at 60± 2ºC. The experimental responses measured were percent of vanadium recovery and vanadium pentoxide content in the precipitate. These impurities are considered representative of those present in a leach liquor from the ore obtained at Campo Alegre de Lourdes (Brazil. The operational variables in this work were used under optimum conditions as determined by the statistical approach. Among the impurities under study, phosphorus exhibited the highest negative influence on the experimental responses. Phosphorus diminished the percent of vanadium recovered from 98.9 to 34.5 and the vanadium oxide content in the precipitate from 91.2 % to 39.3 %.

  4. An Optimized Trichloroacetic Acid/Acetone Precipitation Method for Two-Dimensional Gel Electrophoresis Analysis of Qinchuan Cattle Longissimus Dorsi Muscle Containing High Proportion of Marbling

    OpenAIRE

    Ruijie Hao; Camus Adoligbe; Bijie Jiang; Xianlin Zhao; Linsheng Gui; Kaixing Qu; Sen Wu; Linsen Zan

    2015-01-01

    Longissimus dorsi muscle (LD) proteomics provides a novel opportunity to reveal the molecular mechanism behind intramuscular fat deposition. Unfortunately, the vast amounts of lipids and nucleic acids in this tissue hampered LD proteomics analysis. Trichloroacetic acid (TCA)/acetone precipitation is a widely used method to remove contaminants from protein samples. However, the high speed centrifugation employed in this method produces hard precipitates, which restrict contaminant elimination ...

  5. Fractional Precipitation of Amino Acids from Agro-industrial Residues Using Ethanol

    NARCIS (Netherlands)

    Widyarani, Rani; Bowden, Nathan A.; Kolfschoten, Ruben C.; Sanders, Johan P.M.; Bruins, Marieke E.

    2016-01-01

    Amino acids are important in human and animal diet, as well as being potential feedstocks for chemical production. Amino acids can be obtained from protein after hydrolysis. In addition, several agro-industrial residues already contain a mixture of free amino acids. The objective of this study wa

  6. Effect of precipitation, geographical location and biosynthesis on New Zealand milk powder bulk and fatty acids D/H ratios

    Science.gov (United States)

    Frew, R.; Emad Ehtesham, R.; Van Hale, R.; Hayman, A.; Baisden, T.

    2012-04-01

    D/H ratio measurements provide useful information for the investigation of biogeochemical influences on natural and agricultural produce, particularly with application to food traceability and authentication. Numerous studies have shown that variation of a product's D/H ratio is influenced by both environmental factors and biological processes. This study investigates the D/H ratio of New Zealand milk powder and individual fatty acids, and causal determinants of isotopic variation. One of the key environmental factors is precipitation, and the D/H ratio "isoscaping" of NZ has been undertaken. New Zealand provides a unique geography for these kinds of study in terms of proximity to the ocean and natural geographical variability from sea level to elevations as high as 3700 m. Milk powder samples were collected from different geographical regions from milk processing units, which were supplied by producers in the immediate region. H/D ratios of bulk milk powder and of individual fatty acids were determined. Initial comparison of the precipitation and milk powder bulk D/H data show a very good differentiation from north to southernmost parts of New Zealand and a relation between rain and milk bulk D/H abundance ratio. Almost 98% of milk FAs are in the form of triglycerides that have been extracted and hydrolysed to free FAs. Free FAs were esterified and analyzed with GC-IRMS. Individual FAs show variation in D/H ratio, and all values are depleted relative to the precipitation data. The difference in D/H ratio amongst individual FAs reflects the geographical environment and biological processes i.e. micro-organisms activity in the rumen of the cow. Short chain FAs (less than 8 carbons), particularly C4 (Butyric acid), appear to be key determinants. The variation in the data can be rationalized using statistical multivariate analysis.

  7. The effect of phosphoric acid concentration on the synthesis of nano-whiskers of calcium metaphosphate by chemical precipitation Method

    Science.gov (United States)

    Yao, Nengjian; Zhang, Yin; Kong, Deshuang; Zhu, Jianping; Tao, Yaqiu; Qiu, Tai

    2011-10-01

    Calcium metaphosphate (CMP) nano-whiskers were produced by a chemical precipitation method. In order to produce nano-powders, CMP was prepared by the mixing of two precursors, calcium oxide (CaO) and phosphate acid (H3PO4). Sparingly soluble chemicals, the Ca/P ratio of the mixture was set to be 0.50 to produce stoichiometric CMP, were chemical agitated in phosphate acid solution. At least 3 hours of pre-hydrolysis of phosphorus precursor were required to obtain CMP phase. The CMP powders were dried in a drying oven at 60 °C for 7 days and then followed by a heat treatment at 390 °C for 8hours. The obtained powder was analyzed using XRD, XRF, FT-IR, SEM, TG-DTA, Zeta Potential Meter, Specific Surface Area, and Particle Size Analyzer. The results showed that obtained CMP nano-whiskers have a significantly powder characteristics.

  8. Molecularly imprinted polymer for chlorogenic acid by modified precipitation polymerization and its application to extraction of chlorogenic acid from Eucommia ulmodies leaves.

    Science.gov (United States)

    Miura, Chitose; Li, Hui; Matsunaga, Hisami; Haginaka, Jun

    2015-10-10

    Molecularly imprinted polymers (MIPs) for chlorogenic acid (CGA) were prepared by modified precipitation polymerization using methacrylic acid as a functional monomer, divinylbenzene as a crosslinker and methanol or dimethylsulfoxide as a co-solvent. The prepared MIPs were microspheres with a narrow particle size distribution. Binding experiments and Scatchard analyses revealed that two classes of binding sites, high and low affinity sites, were formed on the MIP. The retention and molecular-recognition properties of the prepared MIP were evaluated using a mixture of water and acetonitrile as a mobile phase in hydrophilic interaction chromatography. With an increase of acetonitrile content, the retention factor of CGA was increased on the MIP. In addition to shape recognition, hydrophilic interactions seem to work for the recognition of CGA on the MIP. The MIP had a specific molecular-recognition ability for CGA, while other related compounds, such as caffeic acid, gallic acid, protocatechuic acid and vanillic acid, could not be recognized by the MIP. Furthermore, the MIP for CGA was successfully applied for extraction of CGA in the leaves of Eucommia ulmodies. PMID:26037163

  9. Soluble species in the Arctic summer troposphere - Acidic gases, aerosols, and precipitation

    Science.gov (United States)

    Talbot, R. W.; Vijgen, A. S.; Harriss, R. C.

    1992-01-01

    The large-scale spatial distribution from 0.15-to 6 km altitude in the North American Arctic troposphere of several soluble acidic gases and major aerosol species during the summertime is reported. The distribution is found to be compositionally consistent on a large spatial scale. The summertime troposphere is an acidic environment, with HCOOH and CH3COOH the principal acidic gases while acidic sulfate aerosols dominate the particulate phase. There appears to be a surface source of NH3 over the pack ice which may originate from decay of dead marine organisms on the ice surface, evolution from surface ocean waters in open ice leads, or release from rotting sea ice. At low altitude over the pack ice this NH34 appears to partially neutralize aerosol acidity. Over sub-Arctic tundra in southeastern Alaska, inputs of marine biogenic sulfur from the Bering Sea appear to be an important source of boundary layer aerosol SO4(2-). The rainwater acidity over the tundra is typical of remote regions.

  10. Generation of dose-response relationships to assess the effects of acidity in precipitation on growth and productivity of vegetation

    International Nuclear Information System (INIS)

    Experiments were performed with several plant species in natural environments as well in a greenhouse and/or tissue culture facilities to establish dose-response functions of plant responses to simulated acidic rain in order to determine environmental risk assessments to ambient levels of acidic rain. Response functions of foliar injury, biomass of leaves and seed of soybean and pinto beans, root yields of radishes and garden beets, and reproduction of bracken fern are considered. The dose-response function of soybean seed yields with the hydrogen ion concentration of simulated acidic rainfalls was expressed by the equation y = 21.06-1.01 log x where y = seed yield in grams per plant and x = the hydrogen concentration if μeq l-1. The correlation coefficient of this relationship was -0.90. A similar dose-response function was generated for percent fertilization of ferns in a forest understory. When percent fertilization is plotted on logarithmic scale with hydrogen ion concentration of the simulated rain solution, the Y intercept is 51.18, slope -0.041 with a correlation coefficient of -0.98. Other dose-response functions were generated that assist in a general knowledge as to which plant species and which physiological processes are most impacted by acidic precipitation. Some responses did not produce convenient dose-response relationships. In such cases the responses may be altered by other environmental factors or there may be no differences among treatment means

  11. Antisolvent Precipitation for the Synthesis of Monodisperse Mesoporous Niobium Oxide Spheres as Highly Effective Solid Acid Catalysts

    KAUST Repository

    Li, Cheng Chao

    2012-03-20

    We have developed a low-cost reaction protocol to synthesize mesoporous Nb 2O 5-based solid acid catalysts with external shape control. In the synthesis, monodisperse glycolated niobium oxide spheres (GNOS) were prepared by means of a simple antisolvent precipitation approach and subsequently converted to mesoporous niobium oxide spheres (MNOS) with a large surface area of 312m 2g -1 by means of the hydrothermal treatment. The antisolvent acetone used to obtain GNOS was recovered through distillation at high purity. The obtained mesoporous MNOS were functionalized further with sulfate anions at different temperatures or incorporated with tungstophosphoric acid to obtain recyclable solid acid catalysts. These MNOS-based catalysts showed excellent performance in a wide range of acid-catalyzed reactions, such as Friedel-Crafts alkylation, esterification, and hydrolysis of acetates. As they are monodisperse spheres with diameters in the submicrometer range, the catalysts can be easily separated and reused. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Generation of dose-response relationships to assess the effects of acidity in precipitation on growth and productivity of vegetation

    Energy Technology Data Exchange (ETDEWEB)

    Evans, L.S.

    1981-01-01

    Experiments were performed with several plant species in natural environments as well in a greenhouse and/or tissue culture facilities to establish dose-response functions of plant responses to simulated acidic rain in order to determine environmental risk assessments to ambient levels of acidic rain. Response functions of foliar injury, biomass of leaves and seed of soybean and pinto beans, root yields of radishes and garden beets, and reproduction of bracken fern are considered. The dose-response function of soybean seed yields with the hydrogen ion concentration of simulated acidic rainfalls was expressed by the equation y = 21.06-1.01 log x where y = seed yield in grams per plant and x = the hydrogen concentration if ..mu..eq l/sup -1/. The correlation coefficient of this relationship was -0.90. A similar dose-response function was generated for percent fertilization of ferns in a forest understory. When percent fertilization is plotted on logarithmic scale with hydrogen ion concentration of the simulated rain solution, the Y intercept is 51.18, slope -0.041 with a correlation coefficient of -0.98. Other dose-response functions were generated that assist in a general knowledge as to which plant species and which physiological processes are most impacted by acidic precipitation. Some responses did not produce convenient dose-response relationships. In such cases the responses may be altered by other environmental factors or there may be no differences among treatment means.

  13. A global assessment of precipitation chemistry and deposition of sulfur, nitrogen, sea salt, base cations, organic acids, acidity and pH, and phosphorus

    Science.gov (United States)

    Vet, Robert; Artz, Richard S.; Carou, Silvina

    2014-08-01

    Investigating and assessing the chemical composition of precipitation and atmospheric deposition is essential to understanding how atmospheric pollutants contribute to contemporary environmental concerns including ecosystem acidification and eutrophication, loss of biodiversity, air pollution and global climate change. Evidence of the link between atmospheric deposition and these environmental issues is well established. The state of scientific understanding of this link is that present levels of atmospheric deposition of sulfur and nitrogen adversely affect terrestrial and aquatic ecosystems, putting forest sustainability and aquatic biodiversity at risk. Nitrogen and phosphorus loadings are linked to impacts on the diversity of terrestrial and aquatic vegetation through biological cycling, and atmospheric deposition plays a major role in the emission-transport-conversion-loss cycle of chemicals in the atmosphere as well as the formation of particulate matter and ozone in the troposphere. Evidence also shows that atmospheric constituents are changing the earth's climate through direct and indirect atmospheric processes. This Special Issue, comprising a single article titled "A global assessment of precipitation chemistry and deposition of sulfur, nitrogen, sea salt, base cations, organic acids, acidity and pH, and phosphorus", presents a recent comprehensive review of precipitation chemistry and atmospheric deposition at global and regional scales. The information in the Special Issue, including all supporting data sets and maps, is anticipated to be of great value not only to the atmospheric deposition community but also to other science communities including those that study ecosystem impacts, human health effects, nutrient processing, climate change, global and hemispheric modeling and biogeochemical cycling. Understanding and quantifying pollutant loss from the atmosphere is, and will remain, an important component of each of these scientific fields as they

  14. Metal and acidity fluxes controlled by precipitation/dissolution cycles of sulfate salts in an anthropogenic mine aquifer

    Science.gov (United States)

    Cánovas, C. R.; Macías, F.; Pérez-López, R.

    2016-05-01

    Underground mine drainages are extremely difficult to study due to the lack of information about the flow path and source proximity in relation to the outflow adit. Geochemical processes controlling metals and acidity fluxes in a complex anthropogenic mine aquifer in SW Spain during the dry and rainy season were investigated by geochemical and statistical tools. High concentrations of acidity, sulfate, metals and metalloids (e.g. Fe, Cu, Zn, As, Cd, Ni, Co) were observed due to intense sulfide oxidation processes. The high residence time inside the anthropogenic aquifer, around 40 days, caused the release of significant quantities of metals linked to host rocks (e.g. Al, Ca, Ge, Li, Mg, REE). The most outstanding characteristic of the acid mine drainage (AMD) outflows is the existence of higher Fe/SO4 molar ratios than those theoretical of pyrite (0.50) during most of the monitored period, due to a fire which occurred in 1949 and remained active for decades. Permanent and temporal retention mechanisms of acidity and metals were observed in the galleries. Once released from sulfide oxidation, Pb and As are sorbed on Fe oxyhydroxysulfate or precipitated as low solubility minerals (i.e. anglesite) inside the galleries. The precipitation of evaporitic sulfate salts during the dry season and the subsequent re-dissolution after rainfall control the fluxes of acidity and main metals (i.e. Fe, Mg, Al) from this anthropogenic aquifer. Some elements, such as Cd, Cu, Ni, REE and Zn, are retained in highly soluble sulfate salts while other elements, such as Ge, Pb and Sc, have a lower response to washout processes due to its incorporation in less soluble sulfate salts. In this way, metal concentration during the washout processes would be controlled by the proportion and solubility of each type of evaporitic sulfate salt stored during the dry season. The recovery of metals of economic interest contained in the AMD could help to self-finance the remediation of these waters in

  15. Production and characterization of poly(3-hydroxybutyrate) generated by Alcaligenes latus using lactose and whey after acid protein precipitation process.

    Science.gov (United States)

    Berwig, Karina Hammel; Baldasso, Camila; Dettmer, Aline

    2016-10-01

    Whey after acid protein precipitation was used as substrate for PHB production in orbital shaker using Alcaligenes latus. Statistical analysis determined the most appropriate hydroxide for pH neutralization of whey after protein precipitation among NH4OH, KOH and NaOH 10%w/v. The results were compared to those of commercial lactose. A scale-up test in a 4L bioreactor was done at 35°C, 750rpm, 7L/min air flow, and 6.5 pH. The PHB was characterized through Fourier Transform Infrared Spectroscopy, thermogravimetry and differential scanning calorimetry. NH4OH provided the best results for productivity (p), 0.11g/L.h, and for polymer yield, (YP/S), 1.08g/g. The bioreactor experiment resulted in lower p and YP/S. PHB showed maximum degradation temperature (291°C), melting temperature (169°C), and chemical properties similar to those of standard PHB. The use of whey as a substrate for PHB production did not affect significantly the final product quality. PMID:27347795

  16. Flavianate, an amino acid precipitant, is a competitive inhibitor of trypsin at pH 3.0

    Directory of Open Access Journals (Sweden)

    J.M. Schneedorf

    1998-09-01

    Full Text Available Textile dyes bind to proteins leading to selective co-precipitation of a complex involving one protein molecule and more than one dye molecule of opposite charge in acid solutions, in a process of reversible denaturation that can be utilized for protein fractionation. In order to understand what occurs before the co-precipitation, a kinetic study using bovine ß-trypsin and sodium flavianate was carried out based on reaction progress curve techniques. The experiments were carried out using a-CBZ-L-Lys-p-nitrophenyl ester as substrate which was added to 50 mM sodium citrate buffer, pH 3.0, containing varying concentrations of ß-trypsin and dye. The reaction was recorded spectrophotometrically at 340 nm for 30 min, and the families of curves obtained were analyzed simultaneously by fitting integrated Michaelis-Menten equations. The dye used behaved as a competitive inhibitor of trypsin at pH 3.0, with Ki = 99 µM; kinetic parameters for the substrate hydrolysis were: Km = 32 µM, and kcat = 0.38/min. The competitive character of the inhibition suggests a specific binding of the first dye molecule to His-57, the only positively charged residue at the active site of the enzyme.

  17. Application of the Nutrient Cycling Model NuCM to a Forest Monitoring Site Exposed to Acidic Precipitation in China

    Institute of Scientific and Technical Information of China (English)

    ZHU Jian-Hua; YU Peng-Tao; T. A. SOGN; WANG Yan-Hui; J.MULDER

    2008-01-01

    The nutrient cycling model NuCM is one of the most detailed models for simulating processes that influence nutrient cycling in forest ecosystems. A field study was conducted at Tieshanping, a Masson pine (Pinus massoniana Lamb.) forest site, in hongqing, China, to monitor the impacts of acidic precipitation on nutrient cycling. NuCM simulations were compared with observed data from the study site. The model produced an approximate fit with the observed data. It simulated the mean annual soil solution concentrations in the two simulation years, whereas it sometimes failed to reproduce seasonal variation. Even though some of the parameters required by modcl running were measured in the field,some others were still highly uncertain and the uncertainties were analyzed. Some of the uncertain parameters necessary for model running should be measured and calibrated to produce a better fit between modeled results and field data.

  18. Trans fatty acids in diets act as a precipitating factor for gut inflammation?

    Science.gov (United States)

    Okada, Yoshikiyo; Tsuzuki, Yoshikazu; Ueda, Toshihide; Hozumi, Hideaki; Sato, Shingo; Hokari, Ryota; Kurihara, Chie; Watanabe, Chikako; Tomita, Kengo; Komoto, Shunsuke; Kawaguchi, Atsushi; Nagao, Shigeaki; Miura, Soichiro

    2013-12-01

    Fatty acids in our daily diet are broadly classified into cis and trans fatty acids (TFAs). TFAs are formed during the manufacturing process of hydrogenated vegetable oils such as margarine. Modern diets such as deep-fried products, frozen foods, and packaged snacks commonly include large quantities of margarine containing TFAs. Although an increased report in the effects of the diet containing TFAs on a risk factor of metabolic syndrome, diabetes mellitus, and coronary heart disease has been observed in the recent years, influence on intestinal inflammation remains unknown. This review describes pro-inflammatory effects of TFAs in our diary diet on various systemic disorders and also discusses a possible role of TFAs on gut inflammation. PMID:24251700

  19. Effect of Surface Precipitate on the Crevice Corrosion in HYBRID and Oxalic Acid Solution

    Energy Technology Data Exchange (ETDEWEB)

    Park, S. Y.; Jung, J. Y.; Won, H. J.; Kim, S. B.; Choi, W. K.; Moon, J. K. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Park, S. J. [Chungnam National Univ., Daejeon (Korea, Republic of)

    2015-05-15

    In this study, we investigated the characteristics of the crevice corrosion for Inconel-600 and 304SS in OA solution according to the change in pH. The evaluation of the crevice corrosion with the chemical thermodynamic analysis identified the effect of the residual chemicals such as iron-oxalate and nickeloxalate to the crevice corrosion behavior. Test results were compared with those of HYBRID (HYdrizine Base Reductive metal Ion Decontamination). The crevice corrosion properties of 304 SS and Inconel-600 in HYBRID and oxalic acid solution were evaluated. In case of oxalic acid solution, the corrosion rate on 304SS was rapidly increased with a pH decrease of around 2, but there was no increase in the corrosion rate on Inconel-600.

  20. Effects of simulated acid precipitation and liming on pine litter decomposition

    Energy Technology Data Exchange (ETDEWEB)

    Ishac, Y.Z.; Hovland, J.

    1976-01-01

    The decomposition of withered lodgepole pine needles (Pinus contorta douglas) has been studied in a laboratory experiment. The needles were picked from trees that have been irrigated with simulated acid rain at pH 5.6 or 3.0. The soil beneath some of the trees was limed. The decomposition of the needles increased with temperature and incubation period. Liming of the soil retarded the decomposition of the needles that have been given rain at pH 3, while irrigation with 50 mm of water per month at pH 3 increased the decomposition compared with 25 mm/month. When needles were incubated in dilute sulphuric acid, the decomposition was reduced at pH 1.8 compared to the decomposition at pH 3.5. At pH 1.0 no decomposition occurred. Fungi were isolated from the needles. The different treatments did not seem to affect the composition of the fungal flora of the needles. The fungi were tested for their ability to decompose cellulose. The four most active cellulose decomposeres were Trichoderma harzianum, Coniothyrium sp., Cladosporium macrocarpum, and a sterile white mycelium. T. harzianum seemed to be more tolerant to acid conditions than the other fungi.

  1. Ultra-Small Fatty Acid-Stabilized Magnetite Nanocolloids Synthesized by In Situ Hydrolytic Precipitation

    Directory of Open Access Journals (Sweden)

    Kheireddine El-Boubbou

    2015-01-01

    Full Text Available Simple, fast, large-scale, and cost-effective preparation of uniform controlled magnetic nanoparticles remains a major hurdle on the way towards magnetically targeted applications at realistic technical conditions. Herein, we present a unique one-pot approach that relies on simple basic hydrolytic in situ coprecipitation of inexpensive metal salts (Fe2+ and Fe3+ compartmentalized by stabilizing fatty acids and aided by the presence of alkylamines. The synthesis was performed at relatively low temperatures (~80°C without the use of high-boiling point solvents and elevated temperatures. This method allowed for the production of ultra-small, colloidal, and hydrophobically stabilized magnetite metal oxide nanoparticles readily dispersed in organic solvents. The results reveal that the obtained magnetite nanoparticles exhibit narrow size distributions, good monodispersities, high saturation magnetizations, and excellent colloidal stabilities. When the [fatty acid] : [Fe] ratio was varied, control over nanoparticle diameters within the range of 2–10 nm was achieved. The amount of fatty acid and alkylamine used during the reaction proved critical in governing morphology, dispersity, uniformity, and colloidal stability. Upon exchange with water-soluble polymers, the ultra-small sized particles become biologically relevant, with great promise for theranostic applications as imaging and magnetically targeted delivery vehicles.

  2. Comparative study on precipitation methods of yellow-cake from acid leachate of rock phosphate and Its purification

    International Nuclear Information System (INIS)

    This study was carried-out to leach uranium from rock phosphate using sulphuric acid in presences of potassium chlorate as an oxidant and to investigate the relative purity of different forms of yellow cakes produced with ammonia ((NH4)2 U2 O7), magnesia (UO3.xH2O) and sodium hydroxide (Na2U2O7) as precipitants, as well as purification of the products with TBP extraction and matching its impurity levels with specification of the commercial products. Alpha-particle spectrometry was for used for determination of activity concentration of uranium isotopes (''2''3''4U and ''2''3''8U) in rock phosphate, resulting green phosphoric acid solution, and in different forms of the yellow cake from which the equivalent mass concentration of uranium was deduced. Likewise, AAS was used for determination of impurities (Pb, Ni, Cd, Fe, Zn, Mn, and Cu). On the average, the activity concentration of uranium in the rock phosphate was 1468±979 Bq/Kg (119.38±79.66 ppm), and 711±252 Bq/L (57.85±20.46 ppm) in the resulting green solution with corresponding percent of dissolution amounting to 48% which is considered low indicating that the experimental conditions (i.e. dissolution container, temperature, PH, retention time) were not optimal. However, the isotopic ratio (''2''3''4U, ''2''3''8U) in all stages of hydrometallurgical process was not much different from unity indicating lack of fractionation. Crude yellow cakes (hydrate uranium trioxide, ammonium diuranate and sodium diuranate) were precipitated from the green solutions prior to separation of iron and once after iron separation. Although, iron was tested using bipyridine and SCN, it was found in all types of crude samples analyzed this might be attributed to either the quality of the reagent used or inhibition of Fe present in the solution by stronger complexing agent. Uranium mass concentration in crude yellow cakes precipitated before iron separation was found following the order: UO3.xH2O>ammonium diuranate

  3. Proceedings of the international workshop on the effects of acid precipitation on vegetation, soils, and terrestrial ecosystems, Brookhaven National Laboratory, June 12 to 14, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Evans, L.S.; Hendrey, G.R. (eds.)

    1979-01-01

    The objectives of the workshop were to determine the levels of current knowledge of the effects of acid precipitation on vegetation, soils, and terrestrial ecosystems; research needed in these areas to understand the environmental impacts of acid rain; and to help coordinate research groups to avoid excessive duplication of research. The workshop was designed so that researchers in the areas of effects of acid precipitation on vegetation, soils, and whole ecosystem approaches could communicate effectively. There was a general consensus that acid rain at extreme ambient levels, or in artificial systems that simulate extreme ambient levels, causes injury to plant tissues. A major area of concern of acid rain injury was thought to be plant reproduction. The overall levels of significance of plant injury among various plant species remain unknown. The most important priorities in the area of effects of acid rain on crops were an evaluation of effects on crop yields and interaction of acid rain in combination with pollutants on various plants. Few participants thought that ambient acid rain loadings have altered soils to such a degree that plants are affected at present, but many thought that acid rain could cause some alterations in soils. The most important research priorities were in the areas of the effects of acid rain on increased leaching of exchangeable plant nutrients and alterations in phosphorous availability. All participants agreed that there are alterations in terrestrial ecosystems from acid precipitation. However, no demonstrated harmful effects were presented from natural ecosystems. Further research on the effects of acid rain on terrestrial ecosystems should be directed mostly toward the interaction of acid rain with toxic elements such as Al, Fe, and Mn and on the effects on nutrient cycling, especially that of nitrogen.

  4. Interaction between uranium and humic acid (II): complexation, precipitation and migration behavior of U(VI) in the presence of humic substances

    International Nuclear Information System (INIS)

    The complexation, precipitation, and migration behavior of uranium in the presence of humic acid (HA) or fulvic acid (FA) were investigated by cation exchange, ultrafiltration and dynamic experiment, respectively. The results showed that (i) complex equilibrium between the uranium and humic substances was achieved at approximately 72 h, (ii) the coordination number varied from 1:1 to 1:2 (U(VI): humic acid) as pH increased from 3 to 6; and (iii), while the complex stability constant decreased when temperature increased, but increased with pH value. We found that the precipitation of uranyl could only be observed in presence of HA, and the precipitation was influenced by conditions, such as pH, uranium concentration, temperature, and the HA concentration. The maximum precipitation proportion up to 60% could be achieved in the condition of 40 mg/L HA solution at pH 6. We further observed that the migration behavior of uranium in soil in the presence of humic acid (HA) or fulvic acid (FA) was different from that in the presence of inorganic colloid, and the effect of humic substances (HS) was limited. (authors)

  5. Limestone characterization to model damage from acidic precipitation: Effect of pore structure on mass transfer

    Science.gov (United States)

    Leith, S.D.; Reddy, M.M.; Irez, W.F.; Heymans, M.J.

    1996-01-01

    The pore structure of Salem limestone is investigated, and conclusions regarding the effect of the pore geometry on modeling moisture and contaminant transport are discussed based on thin section petrography, scanning electron microscopy, mercury intrusion porosimetry, and nitrogen adsorption analyses. These investigations are compared to and shown to compliment permeability and capillary pressure measurements for this common building stone. Salem limestone exhibits a bimodal pore size distribution in which the larger pores provide routes for convective mass transfer of contaminants into the material and the smaller pores lead to high surface area adsorption and reaction sites. Relative permeability and capillary pressure measurements of the air/water system indicate that Salem limestone exhibits high capillarity end low effective permeability to water. Based on stone characterization, aqueous diffusion and convection are believed to be the primary transport mechanisms for pollutants in this stone. The extent of contaminant accumulation in the stone depends on the mechanism of partitioning between the aqueous and solid phases. The described characterization techniques and modeling approach can be applied to many systems of interest such as acidic damage to limestone, mass transfer of contaminants in concrete and other porous building materials, and modeling pollutant transport in subsurface moisture zones.

  6. An Optimized Trichloroacetic Acid/Acetone Precipitation Method for Two-Dimensional Gel Electrophoresis Analysis of Qinchuan Cattle Longissimus Dorsi Muscle Containing High Proportion of Marbling.

    Directory of Open Access Journals (Sweden)

    Ruijie Hao

    Full Text Available Longissimus dorsi muscle (LD proteomics provides a novel opportunity to reveal the molecular mechanism behind intramuscular fat deposition. Unfortunately, the vast amounts of lipids and nucleic acids in this tissue hampered LD proteomics analysis. Trichloroacetic acid (TCA/acetone precipitation is a widely used method to remove contaminants from protein samples. However, the high speed centrifugation employed in this method produces hard precipitates, which restrict contaminant elimination and protein re-dissolution. To address the problem, the centrifugation precipitates were first grinded with a glass tissue grinder and then washed with 90% acetone (TCA/acetone-G-W in the present study. According to our result, the treatment for solid precipitate facilitated non-protein contaminant removal and protein re-dissolution, ultimately improving two-dimensional gel electrophoresis (2-DE analysis. Additionally, we also evaluated the effect of sample drying on 2-DE profile as well as protein yield. It was found that 30 min air-drying did not result in significant protein loss, but reduced horizontal streaking and smearing on 2-DE gel compared to 10 min. In summary, we developed an optimized TCA/acetone precipitation method for protein extraction of LD, in which the modifications improved the effectiveness of TCA/acetone method.

  7. Decolorization of acid and basic dyes: understanding the metabolic degradation and cell-induced adsorption/precipitation by Escherichia coli.

    Science.gov (United States)

    Cerboneschi, Matteo; Corsi, Massimo; Bianchini, Roberto; Bonanni, Marco; Tegli, Stefania

    2015-10-01

    Escherichia coli strain DH5α was successfully employed in the decolorization of commercial anthraquinone and azo dyes, belonging to the general classes of acid or basic dyes. The bacteria showed an aptitude to survive at different pH values on any dye solution tested, and a rapid decolorization was obtained under aerobic conditions for the whole collection of dyes. A deep investigation about the mode of action of E. coli was carried out to demonstrate that dye decolorization mainly occurred via three different pathways, specifically bacterial induced precipitation, cell wall adsorption, and metabolism, whose weight was correlated with the chemical nature of the dye. In the case of basic azo dyes, an unexpected fast decolorization was observed after just 2-h postinoculation under aerobic conditions, suggesting that metabolism was the main mechanism involved in basic azo dye degradation, as unequivocally demonstrated by mass spectrometric analysis. The reductive cleavage of the azo group by E. coli on basic azo dyes was also further demonstrated by the inhibition of decolorization occurring when glucose was added to the dye solution. Moreover, no residual toxicity was found in the E. coli-treated basic azo dye solutions by performing Daphnia magna acute toxicity assays. The results of the present study demonstrated that E. coli can be simply exploited for its natural metabolic pathways, without applying any recombinant technology. The high versatility and adaptability of this bacterium could encourage its involvement in industrial bioremediation of textile and leather dyeing wastewaters.

  8. MODIFICATION OF PRECIPITATED CALCIUM CARBONATE FILLER USING SODIUM SILICATE/ZINC CHLORIDE BASED MODIFIERS TO IMPROVE ACID-RESISTANCE AND USE OF THE MODIFIED FILLER IN PAPERMAKING

    Directory of Open Access Journals (Sweden)

    Jing Shen

    2009-11-01

    Full Text Available In order to improve the acid-resistant property of papermaking grade precipitated calcium carbonate filler and to obtain modified filler in powder form, sodium silicate/zinc chloride based modifiers were used in filler modification, and the use of modified filler in papermaking of deinked pulp derived from recycled newspaper was also preliminarily investigated. Under the preliminarily optimized experimental conditions, when sodium silicate, zinc chloride, sodium hexametaphosphate, and phosphoric acid with dosages of 10 wt%, 3 wt%, 1 wt% and 0.2 wt%, respectively, were used as modifiers, and when the temperature, aging time, and PCC concentration during the filler modification process was 70 oC, 7 h and 9.1 wt%, respectively, the acid-resistant property of filler was significantly improved after modification, as evaluated using alum consumption and pH methods. The use of modified precipitated calcium carbonate filler prepared under the optimized conditions provided considerably more brightness and light scattering improvement in comparison to unmodified filler, and filler modification was found to have only negligible influence on tensile and burst strength of the paper, air permeability of the paper, and retention performance of the filler. Surface analysis of the modified filler using XPS and SEM confirmed the occurring of surface encapsulation and modification of precipitated calcium carbonate filler when the relevant modifiers were used in filler modification. The encapsulating effect of modifiers on filler was thought to be favorable to improvement in acid-resistant property, and optical properties of the filled paper.

  9. Fatty Acids of Densely Packed Embryos of Carcinus maenas Reveal Homogeneous Maternal Provisioning and No Within-Brood Variation at Hatching.

    Science.gov (United States)

    Rey, Felisa; Moreira, Ana S P; Ricardo, Fernando; Coimbra, Manuel A; Domingues, M Rosário M; Domingues, Pedro; Rosa, Rui; Queiroga, Henrique; Calado, Ricardo

    2016-04-01

    Embryonic development of decapod crustaceans relies on yolk reserves supplied to offspring through maternal provisioning. Unequal partitioning of nutritional reserves during oogenesis, as well as fluctuating environmental conditions during incubation, can be sources of within-brood variability. Ultimately, this potential variability may promote the occurrence of newly hatched larvae with differing yolk reserves and an unequal ability to endure starvation and/or suboptimal feeding during their early pelagic life. The present study evaluated maternal provisioning by analyzing fatty acid (FA) profiles in newly extruded embryos of Carcinus maenas Also assessed were the dynamics of such provisioning during embryogenesis, such as embryo location within the regions of the brooding chamber (left external, left internal, right external, and right internal). The FA profiles surveyed revealed a uniform transfer of maternal reserves from the female to the entire mass of embryos, and homogeneous embryonic development within the brooding chamber. Although C. maenas produces a densely packed mass of embryos that are unevenly distributed within its brooding chamber, this factor is not a source of within-brood variability during incubation. This finding contrasts with data already recorded for larger-sized brachyuran crabs, and suggests that the maternal behavior of C. maenas promotes homogeneous lipid catabolism during embryogenesis. PMID:27132134

  10. Synthesis of aqueous suspensions of magnetic nanoparticles with the co-precipitation of iron ions in the presence of aspartic acid

    Science.gov (United States)

    Pušnik, Klementina; Goršak, Tanja; Drofenik, Miha; Makovec, Darko

    2016-09-01

    There is increasing demand for the production of large quantities of aqueous suspensions of magnetic iron-oxide nanoparticles. Amino acids are one possible type of inexpensive, nontoxic, and biocompatible molecules that can be used as the surfactants for the preparation of stable suspensions. This preparation can be conducted in a simple, one-step process based on the co-precipitation of Fe3+/Fe2+ ions in the presence of the amino acid. However, the presence of this amino acid changes the mechanism of the magnetic nanoparticles' formation. In this investigation we analyzed the influence of aspartic amino acid (Asp) on the formation of magnetic iron-oxide nanoparticles during the co-precipitation. The process of the nanoparticles' formation was followed using a combination of TEM, x-ray diffractometry, magnetic measurements, in-situ FT-IR spectroscopy, and chemical analysis, and compared with the formation of nanoparticles without the Asp. The Asp forms a coordination complex with the Fe3+ ions, which impedes the formation of the intermediate iron oxyhydroxide phase and suppresses the growth of the final magnetic iron-oxide nanoparticles. Slower reaction kinetics can lead to the formation of nonmagnetic secondary phases. The aspartic-acid-absorbed nanoparticles can be dispersed to form relatively concentrated aqueous suspensions displaying a good colloidal stability at an increased pH.

  11. A perspective of stepwise utilisation of Bayer red mud: Step two--Extracting and recovering Ti from Ti-enriched tailing with acid leaching and precipitate flotation.

    Science.gov (United States)

    Huang, Yanfang; Chai, Wencui; Han, Guihong; Wang, Wenjuan; Yang, Shuzhen; Liu, Jiongtian

    2016-04-15

    The extraction and recovery of Ti from Ti-enriched tailing with acid leaching and precipitate flotation, as one of the critical steps, was proposed for the stepwise utilization of red mud. The factors influencing acid leaching and precipitate flotation were examined by factorial design. The leaching thermodynamics, kinetics of Ti(4+), Al(3+) and Fe(3+), and the mechanism of selectively Fe(3+) removal using [Hbet][Tf2N] as precipitating reagent were discussed. The extracting of Ti(4+), Al(3+) and Fe(3+) in concentrated H2SO4 is controlled by diffusion reactions, depending mainly upon leaching time and temperature. The maximum extracting efficiency of Ti(4+) is approximately 92.3%, whereas Al(3+) and Fe(3+) leaching are respectively 75.8% and 84.2%. [Hbet][Tf2N], as a precipitating reagent, operates through a coordination mechanism in flotation. The pH value is the key factor influencing the flotation recovery of Ti(4+), whereas the dosage of precipitating reagent is that for Al(3+) recovery. The maximum flotation recovery of Ti(4+) is 92.7%, whereas the maximum Al(3+) recovery is 93.5%. The total recovery rate for extracting and recovering titanium is 85.5%. The liquor with Ti(4+) of 15.5g/L, Al(3+) of 30.4g/L and Fe(3+) of 0.48g/L was obtained for the following hydrolysis step in the integrated process for red mud utilisation. PMID:26799223

  12. Caprylic acid-induced impurity precipitation from protein A capture column elution pool to enable a two-chromatography-step process for monoclonal antibody purification.

    Science.gov (United States)

    Zheng, Ji; Wang, Lu; Twarowska, Barbara; Laino, Sarah; Sparks, Colleen; Smith, Timothy; Russell, Reb; Wang, Michelle

    2015-01-01

    This article presents the use of caprylic acid (CA) to precipitate impurities from the protein A capture column elution pool for the purification of monoclonal antibodies (mAbs) with the objective of developing a two chromatography step antibody purification process. A CA-induced impurity precipitation in the protein A column elution pool was evaluated as an alternative method to polishing chromatography techniques for use in the purification of mAbs. Parameters including pH, CA concentrations, mixing time, mAb concentrations, buffer systems, and incubation temperatures were evaluated on their impacts on the impurity removal, high-molecular weight (HMW) formation and precipitation step yield. Both pH and CA concentration, but not mAb concentrations and buffer systems, are key parameters that can affect host-cell proteins (HCPs) clearance, HMW species, and yield. CA precipitation removes HCPs and some HMW species to the acceptable levels under the optimal conditions. The CA precipitation process is robust at 15-25°C. For all five mAbs tested in this study, the optimal CA concentration range is 0.5-1.0%, while the pH range is from 5.0 to 6.0. A purification process using two chromatography steps (protein A capture column and ion exchange polishing column) in combination with CA-based impurity precipitation step can be used as a robust downstream process for mAb molecules with a broad range of isoelectric points. Residual CA can be effectively removed by the subsequent polishing cation exchange chromatography.

  13. 酒糟与分离的沉淀产物中的氨基酸分析%Analysis of amino acids in distilled grain and its precipitates

    Institute of Scientific and Technical Information of China (English)

    叶翔; 冷云伟; 陈翔; 李浩

    2011-01-01

    Distiller's grain contains a considerable amount of protein and amino acids. HPLC with pre-column derivatization were used to detect and analysis amino acids in distiller's grain and precipitate. The amino acid content in distiller's grains was up to 13.45%, and it was 22.72% in precipitate, which was nearly two times as that in distilled grain. The nutritional value and economic value of distilled grain has been greatly improved by centrifuge. In addition, for distilled grain and its centrifuged precipitate, the types of amino acid were very comprehensive, and the proportion of amino acids also was moderate, which could be a very good source for animal feeds.%在酒糟中含有相当数量的残留蛋白质与氨基酸,采用高效液相色谱柱前衍生法分别对酒糟与其分离产物沉淀中的氨基酸进行检测比较分析,发现酒糟中氨基酸含量高达13.45%,而沉淀产物中的氨基酸更是高达22.72%,其含量相比酒糟中提高了近一倍.通过离心分离后的酒糟的营养价值和经济价值都得到大大地提高.另外,酒糟及其沉淀产物中氨基酸种类十分全面,比例适中,是一种非常优秀的动物饲料.

  14. Preparation of ellagic acid molecularly imprinted polymeric microspheres based on distillation-precipitation polymerization for the efficient purification of a crude extract.

    Science.gov (United States)

    Zhang, Hua; Zhao, Shangge; Zhang, Lu; Han, Bo; Yao, Xincheng; Chen, Wen; Hu, Yanli

    2016-08-01

    Molecularly imprinted polymeric microspheres with a high recognition ability toward the template molecule, ellagic acid, were synthesized based on distillation-precipitation polymerization. The as-obtained polymers were characterized by scanning electron microscopy, infrared spectroscopy, and thermogravimetric analysis. Static, dynamic, and selective binding tests were adopted to study the binding properties and the molecular recognition ability of the prepared polymers for ellagic acid. The results indicated that the maximum static adsorption capacity of the prepared polymers toward ellagic acid was 37.07 mg/g and the adsorption equilibrium time was about 100 min when the concentration of ellagic acid was 40 mg/mL. Molecularly imprinted polymeric microspheres were also highly selective toward ellagic acid compared with its analogue quercetin. It was found that the content of ellagic acid in the pomegranate peel extract was enhanced from 23 to 86% after such molecularly imprinted solid-phase extraction process. This work provides an efficient way for effective separation and enrichment of ellagic acid from complex matrix, which is especially valuable in industrial production. PMID:27311588

  15. Application of dissolvable layered double hydroxides as sorbent in dispersive solid-phase extraction and extraction by co-precipitation for the determination of aromatic acid anions.

    Science.gov (United States)

    Tang, Sheng; Lee, Hian Kee

    2013-08-01

    Three types of magnesium-aluminum layered double hydroxides were synthesized and employed as solid-phase extraction (SPE) sorbents to extract several aromatic acids (protocatechuic acid, mandelic acid, phthalic acid, benzoic acid, and salicylic acid) from aqueous samples. An interesting feature of these sorbents is that they dissolve when the pH of the solution is lower than 4. Thus, the analyte elution step, as needed in conventional sorbent-based extraction, was obviated by dissolving the sorbent in acid after extraction and separation from the sample solution. The extract was then directly injected into a high-performance liquid chromatography-ultraviolet detection system for analysis. In the key adsorption process, both dispersive SPE and co-precipitation extraction with the sorbents were conducted and experimental parameters such as pH, temperature, and extraction time were optimized. The results showed that both extraction methods provided low limits of detection (0.03-1.47 μg/L) and good linearity (r(2) > 0.9903). The optimized extraction conditions were applied to human urine and sports drink samples. This new and interesting extraction approach was demonstrated to be a fast and efficient procedure for the extraction of organic anions from aqueous samples. PMID:23855757

  16. Preparation of porous carboxymethyl chitosan grafted poly (acrylic acid) superabsorbent by solvent precipitation and its application as a hemostatic wound dressing.

    Science.gov (United States)

    Chen, Yu; Zhang, Yong; Wang, Fengju; Meng, Weiwei; Yang, Xinlin; Li, Peng; Jiang, Jianxin; Tan, Huimin; Zheng, Yongfa

    2016-06-01

    The volume phase transition of a hydrogel initiated by shrinking may result in complex patterns on its surface. Based on this unique property of hydrogel, we have developed a novel solvent precipitation method to prepare a kind of novel superabsorbent polymers with excellent hemostatic properties. A porous carboxymethyl chitosan grafted poly (acrylic acid) (CMCTS-g-PAA) superabsorbent polymer was prepared by precipitating CMCTS-g-PAA hydrogel with ethanol. Its potential application in hemostatic wound dressing was investigated. The results indicate that the modified superabsorbent polymer is non-cytotoxic. It showed a high swelling capacity and better hemostatic performance in the treatments of hemorrhage model of ear artery, arteria cruralis and spleen of the New Zealand white rabbit than the unmodified polymer and other commonly used clinic wound dressings. The hemostatic mechanism of the porous CMCTS-g-PAA polymer was also discussed. PMID:27040191

  17. Acidification of soil-water in low base-saturated sand soils of the superior uplands under acid and normal precipitation.

    Science.gov (United States)

    Harris, A R

    1989-04-01

    Lakes and streams are acidified by direct precipitation and water channeled through nearby soils, but water in low base-saturation soils can produce highly acidic percolate after prolonged contact and subsequent degassing in surface waters. Theories advanced by Reuss (1983), Reuss and Johnson (1985), and Seip and Rustad (1984) suggest that soils with less than 15% base saturation are susceptible to soil-water pH depression of up to 0.4 unit, which is sufficient to cause negative alkalinity in soil solutions. High concentrations of mobile anions (notably sulfate) are responsible for the negative alkalinity and these solutions on CO2 degassing in surface waters can retain acidities equivalent to a pH value of 5.0 or less. This mechanism purports to explain why some lakes acidify when they are surrounded by acid soils and cation leaching is not required.Ambient precipitation set to pH 5.4 and pH 4.2 was applied to columns of low base-saturated, sand, soils, starting in 1985. The columns (15 cm diameter and 150 cm long) were collected from soils with base saturations falling into one of three groups (0-10, 10-20, and 20-40%) from national forests in the Superior Uplands area (includes Boundary Waters Canoe Area, Rainbow Lakes, Sylvania, Moquah Barrens, and other Wilderness and Natural areas). The soils were Haplorthods and Udipsamments mainly from outwash plains.The soil columns were instrumented and reburied around a subterranean structure used to collect leachate water and to maintain natural temperature, air, and light conditions. Three humus treatments were applied to soil column (none, northern hardwood, and jack pine) to measure the effect of natural acidification compared to acidification by acid precipitation. The cores were treated with precipitation buffered to pH 5.4 to simulate natural rain and pH 4.2 to simulate acid rain.Columns were treated in 1985 and 1986 with approximately 200 cm of buffered precipitation each year over the frost-free season. Data is

  18. Effects of experimental acid precipitation and liming on vigor, species abundance, and mineral nutrition of ground vegetation in a Norway spruce stand

    Energy Technology Data Exchange (ETDEWEB)

    Rodenkirchen, H.

    1986-09-01

    The effects of simulated sulfuric acid rain and liming on ground vegetation of a 74-year-old Norway Spruce stand were analysed since summer of 1983. During the first two growing seasons no significant change in species composition had occurred on any plot. The frequently applied acid rain injured some constant moss species, this was reflected by chlorosis, necroses, and reduced average coverage or frequency. Damaged moss segments had decreased Ca-, Mg-, Mn-, Zn- and K-concentrations. Some secondary moss species, however were more tolerant to acid precipitation. Liming with dolomite at the beginning of the experiment improved the Ca- and Mg-nutrition of all investigated species (Thuidium tamariscinum, Oxalis acetosella, spruce seedlings), lowered the intensity of injury by acid rain with mosses, and reduced the Mn- (and Zn-)uptake of the vascular plant species. The combination of liming and irrigation with acid or 'normal' water strongly increased the abundance of the herb Oxalis acetosella. Without liming the same species responded to acid rain with lower Ca- (and Mg-)contents in leaves but no visible foliar damage occurred.

  19. Correlation between precipitation and geographical location of the δ2H values of the fatty acids in milk and bulk milk powder

    Science.gov (United States)

    Ehtesham, E.; Baisden, W. T.; Keller, E. D.; Hayman, A. R.; Van Hale, R.; Frew, R. D.

    2013-06-01

    Hydrogen isotope ratios (δ2H) have become a tool for food traceability and authentication of agricultural products. The principle is that the isotopic composition of the produce is influenced by environmental and biological factors and hence exhibits a spatial differentiation of δ2H. This study investigates the variation in δ2H values of New Zealand milk, both in the bulk powder and individual fatty acids extracted from milk samples from dairy factories across New Zealand. Multivariate statistical analyses were used to test for relationships between δ2H of bulk milk powder, milk fatty acid and geographical location. Milk powder samples from different regions of New Zealand were found to exhibit patterns in isotopic composition similar to the corresponding regional precipitation associated with their origin. A model of δ2H in precipitation was developed based on measurements between 2007 and 2010 at 51 stations across New Zealand (Frew and Van Hale, 2011). The model uses multiple linear regressions to predict daily δ2H from 2 geographic and 5 rain-weighted climate variables from the 5 × 5 km New Zealand Virtual Climate Station Network (VCSN). To approximate collection radius for a drying facility the modelled values were aggregated within a 50 km radius of each dairy factory and compared to observed δ2H values of precipitation and bulk milk powder. Daily δ2H predictions for the period from August to December for the area surrounding the sample collection sites were highly correlated with the δ2H values of bulk milk powder. Therefore the δ2H value of milk fatty acids demonstrates promise as a tool for determining the provenance of milk powders and products where milk powder is an ingredient. Separation of milk powder origin to geographic sub-regions within New Zealand was achieved. Hydrogen isotope measurements could be used to complement traditional tracking systems in verifying point of origin.

  20. Study of molybdenum (VI) complexation and precipitation by zirconium (IV) in strongly acid medium. Application to nuclear spent fuel dissolution; Etude de la complexation et de la precipitation du molybdene (VI) par le zirconium (IV) en milieu tres acide. Application a la dissolution du combustible nucleaire irradie

    Energy Technology Data Exchange (ETDEWEB)

    Esbelin, E

    1999-07-01

    These last years the formation of solid deposits has been observed in the dissolution workshops of the La Hague plant. A sample of the solid was withdrawn for expertise: molybdenum and zirconium are the two major components of the solid, identified as zirconium molybdate. This thesis consisted in the approach of the mechanisms in solution liable to induce precipitate formation. After a bibliographical overview on the chemistry of Mo(VI) in highly acidic solution, this system was studied by absorption spectrophotometry in perchloric medium. The implication of two major forms of Mo(VI) in a dimerization equilibrium was confirmed by this way and by {sup 95}Mo NMR. The principal parameters governing this equilibrium were identified. It is thus shown that the molybdenum dimerization reaction is exothermic. Disturbance of the Mo(VI) system in highly acidic solution by Zr(IV) was also studied. In a restricted experimental field, for which 'conventional' exploitation methodologies had to be adapted to the system, a main complex of stoichiometry 1:1 between Mo(VI) and Zr(IV) was found. The precipitation study of Mo(VI) by Zr(IV) under conditions close to those of the dissolution medium of nuclear spent fuel was undertaken. The main parameters which control precipitation kinetics were identified. The results obtained reveal that precipitation is controlled by a single macroscopic process and therefore can be described by a single equation. The solid obtained is composed of only one phase presenting a Mo:Zr non-stoichiometry when compared to the theoretical formula ZrMo{sub 2}O{sub 7}(OH){sub 2},2H{sub 2}O. At last, on the basis of the research results, a descriptive mechanism of the system is proposed in which intervenes a 1:1 intermediate complex, much more soluble than a probable 2:1 precipitation precursor. (author)

  1. A report on acid precipitation and its effects on fish and wildlife resources in Minnesota and Wisconsin

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — An overview of acid rain in Minnesota and Wisconsin, together with suggestions for further research and contact information for state and federal employees involved...

  2. Effects of precipitation variation on severe acid rain in southern China%降水变化对中国南方强酸雨分布的影响

    Institute of Scientific and Technical Information of China (English)

    谢志清; 杜银; 曾燕; 李亚春; 严明良; 焦圣明

    2009-01-01

    Acid rain has been recognized as a serious environmental problem in China since the 1980s, but little is known about the effects of the climatic change in regional precipitation on the temporal and spatial variability of severe acid rain. We present the effects of the re-gional precipitation trend change on the area and intensity of severe acid rain in southern China, and the spatio-temporal distribution characteristics of SO2 and NO2 concentrations are analyzed on the basis of SO2 and NO2 column concentration data. The results are as follows. (1) The emission levels of SO2 and NO2 have reached or passed the precipitation scavenging capacity in parts of southern China owing to the emission totals of SO2 and NO2 increasing from 1993 to 2004. (2) Notable changes in the proportion of cities subject to severe acid rain occurred mainly in the south of the middle-lower reaches of the Yangtze River during 1993-2004. With an abrupt change in 1999, the severe acid rain regions were mainly located in central and western China during 1993-1999 and moved obviously eastward to the south of the lower-middle reaches of the Yangtze River with the proportion of cities subject to se-vere acid rain increasing significantly from 2000 to 2004. (3) The spatial distribution and variation in the seasonal precipitation change rate of more than 10 mm/10a are similar to those of severe acid rain in southern China. An abrupt change in 1999 is seen for winter and summer precipitation, the same as for the proportion of cities subject to severe acid rain in southern China. The significant increase in summer storm precipitation from 1991 to 1999 mitigated the annual precipitation acidity in the south of the Yangtze River and reduced the area of severe acid rainfall. On the other hand, the decrease in storm rainfall in summer ex-panded the area of severe acid rainfall in the south of the Yangtze River in 2000-2006. Therefore, the change in seasonal precipitation is an important factor in the

  3. LC-MS/MS analysis of Δ9-tetrahydrocannabinolic acid A in serum after protein precipitation using an in-house synthesized deuterated internal standard.

    Science.gov (United States)

    Wohlfarth, Ariane; Roth, Nadine; Auwärter, Volker

    2012-06-01

    An assay based on liquid chromatography/tandem mass spectrometry is presented for the fast, precise and sensitive quantitation of Δ9-tetrahydrocannabinolic acid A (THCA) in serum. THCA is the biogenetic precursor of Δ9-tetrahydrocannabinol in cannabis and has aroused interest in the pharmacological and forensic field especially as a potential marker for recent cannabis use. After addition of deuterated THCA, synthesized from D(3)-THC as starting material, and protein precipitation, the analytes were separated using gradient elution on a Luna C18 column (150 × 2.0 mm × 5 µm) with 0.1% formic acid and acetonitrile/0.1% formic acid. Data acquisition was performed on a triple quadrupole linear ion trap mass spectrometer in multiple reaction monitoring mode with negative electrospray ionization. After optimization, the following sample preparation procedure was used: 200 μL serum was spiked with internal standard solution and methanol and then precipitated 'in fractions' with 500 μL ice-cold acetonitrile. After storage and centrifugation, the supernatant was evaporated and the residue redissolved in mobile phase. The assay was fully validated according to international guidelines including, for the first time, the assessment of matrix effects and stability experiments. Limit of detection was 0.1 ng/mL, and limit of quantification was 1.0 ng/mL. The method was found to be selective and proved to be linear over a range of 1.0 to 100 ng/mL using a 1/x weighted calibration model with regression coefficients >0.9996. Accuracy and precision data were within the required limits (RSD ≤ 8.6%, bias: 2.4 to 11.4%), extractive yield was greater than 84%. The analytes were stable in serum samples after three freeze/thaw cycles and storage at -20 °C for one month.

  4. 1992-2013年安徽省酸雨变化特征及成因分析%The trend of precipitation acidity in Anhui province from 1992 to 2013 and its possible reasons

    Institute of Scientific and Technical Information of China (English)

    石春娥; 邓学良; 杨元建; 吴必文

    2015-01-01

    据安徽气象部门酸雨观测资料分析,2006年以来,安徽酸雨有以下特点:(1)空间上,安徽南北各地,不论城市还是高山均观测到强酸雨。其中,以合肥和安庆最为突出,强酸雨频率最高,多年年均 pH 值接近强酸雨等级。从多年平均降水 pH 值来看,仅阜阳站为非酸性等级,其余各站皆为酸性等级。时间上,安徽酸雨季节变化明显,冬半年较重,夏半年偏轻。(2)从全省情况看,2009年前后酸雨最为严重。最近三年,各地降水酸性程度均有所减轻。以合肥酸雨变化为例,22年的变化趋势可分为三个阶段:1992—1999年,无明显变化趋势;2000—2008年,酸雨明显增强;2009—2013年,酸雨略有改善。(3)污染程度方面,黄山光明顶降水比较洁净,铜陵和马鞍山的降水受污染程度最为严重。(4)离子组成方面,酸雨成分逐渐由“硫酸型”转变为“硫酸硝酸混合型”,与20世纪80—90年代相比,降水中硝酸根离子和氨根离子浓度显著上升。近年来,周边省份二氧化硫排放减少是导致我省酸雨污染减轻的主要原因。然而由于大气中氮氧化物增加,导致我省酸雨由“硫酸型”向“硫酸硝酸混合型”转变。%There are seven acid rain monitoring stations in Anhui province operated by Anhui meteorological bureau. According to the measurements at those seven stations and the field observations of rain chemistry at Mountain Huangshan and Hefei,together with results in previous studies,the trend of precipitation acidity and characteristics of acid precipitation in Anhui province were analyzed.The main conclusions were summarized as follow:(1)During 2006-2013,strong acid precipitation can be observed at all stations,no matter whether in southern or northern Anhui,at urban site or at alpine site.Among the seven stations,precipitations at Hefei and Anqing stations were the most prominent for the highest frequencies of strong acid precipitation

  5. Effects of acid precipitation on a boreal forest ecosystem. Ion budgets and changes in water chemistry for the Laflamme Lake watershed

    Energy Technology Data Exchange (ETDEWEB)

    Papineau, M.

    1987-01-01

    Data on surface waters have been gathered at the Laflamme Lake Watershed in Quebec as part of an ion budget research program. This watershed was set up in 1980 to assess the effects of long range transport of airborne pollutants on a boreal forest ecosystem receiving moderate to high sulphate loading. Precipitation data indicates that between 1981 and 1984, the average pH of water falling onto the watershed was 4.4, that precipitation quality is cyclic and that loading is episodic. The main components of precipitation on an equivalent basis are sulfate, hydrogen, nitrate and ammonium ions. ALthough the sulphate to nitrate ration is 2:1 on a yearly basis, nitrate ions are more important than sulphates in January. Since water and pollutants build up in the snowpack, spring melt is a critical period during which concentrations in surface waters and exports from the watershed are modifed for many parameters especially hydrogen and bicarbonate ions. Lake water quality is characteristic of lakes that are very sensitive to acidification. High sulfate values seem to indicate that the watershed has been affected by atmospheric loading. The average pH of the lake (6.4) indicates that the lake is not yet greatly acidified. Important buffering occurs in the soil and surficial deposits of the watershed. Stream water is slightly less mineralized, slightly more acidic and shows more pronounced changes in water quality than lake water. Over the last five years, sulfate, conductivity and some heavy metal levels have increased in surface waters while no significant trends were seen for pH and alkalinity. In other Quebec monitoring lakes, trends of decreasing pH were seen during this period. When wet loading is compared to stream output, hydrogen and nitrate ions are seen to be retained in the watershed while Ca, Mg, Na, K, sulphate and chloride are lost. 63 refs. 31 figs. 32 tabs.

  6. Production and functional evaluation of a protein concentrate from giant squid (Dosidicus gigas) by acid dissolution and isoelectric precipitation.

    Science.gov (United States)

    Cortés-Ruiz, Juan A; Pacheco-Aguilar, Ramón; Elena Lugo-Sánchez, M; Gisela Carvallo-Ruiz, M; García-Sánchez, Guillermina

    2008-09-15

    A protein concentrate from giant squid (Dosidicus gigas) was produced under acidic conditions and its functional-technological capability evaluated in terms of its gel-forming ability, water holding capacity and colour attributes. Technological functionality of the concentrate was compared with that of squid muscle and a neutral concentrate. Protein-protein aggregates insoluble at high ionic strength (I=0.5M), were detected in the acidic concentrate as result of processing with no preclusion of its gel-forming ability during the sol-to-gel thermal transition. Even though washing under acidic condition promoted autolysis of the myosin heavy chain, the acidic concentrate displayed an outstanding ability to gel giving samples with a gel strength of 455 and 1160gcm at 75% and 90% compression respectively, and an AA folding test grade indicative of high gel strength, elasticity, and cohesiveness. The process proved to be a good alternative for obtaining a functional protein concentrate from giant squid muscle. PMID:26049243

  7. Evaluation of Antioxidant Ability In Vitro and Bioavailability of trans-Cinnamic Acid Nanoparticle by Liquid Antisolvent Precipitate

    Directory of Open Access Journals (Sweden)

    Wengang Li

    2016-01-01

    Full Text Available TCD is a kind of organic acid that is isolated from cinnamon bark or benzoin. TCD has significant antioxidant activity and is widely used in pharmaceutical, cosmetic, and food additives. But TCD has shortcomings of low bioavailability due to poor water solubility. Therefore, we use ethanol as a solvent, deionized water as antisolvent, and hydroxypropyl methylcellulose (HPMC as the surfactant to prepare TCD nanoparticle powder. The optimum preparation conditions were determined as follows: TCD-ethanol solution concentration was 170 mg/mL, the volume ratio of antisolvent was 4 times that of solvent, and the amount of the surfactant was 0.3% stirred for 10 min by 2500 rpm; TCD nanoparticle with a mean particle size (MPS of 130±12.5 nm is obtained under the optimum conditions. SEM, FT-IR, LC-MS/MS, XRD, and DSC were used to characterize the TCD nanoparticle. The results showed that the chemical structure of TCD nanoparticle was not changed, but the crystallization was significantly reduced. Solubility, dissolution rate, antioxidant activity, the in vitro transdermal penetration, and bioavailability of TCD nanoparticles were all much better than these of the raw TCD. These results suggested that TCD nanoparticle might have potential value to become a new oral or transdermal TCD formulation with high bioavailability.

  8. 碱提酸沉法提取茶叶蛋白质的研究%Extraction of Tea Protein using Alkali Extraction-acid Precipitation Method

    Institute of Scientific and Technical Information of China (English)

    陆晨; 张士康; 朱科学; 王彬; 周惠明

    2011-01-01

    Extraction of tea-protein from green tea by using alkali extraction and acid precipitation was investigated. Amino acid compositions of the tea protein ware also analyzed. The results showed that the optimum extraction parameters were NaOH 0.3 mol/L, green tes/water solution (m/V) 1:25, temperature50 ℃, stirring time 1 h and extraction times twice, under which the protein extraction efficiency was 85.50%. The best pI of the tea protein was 3.0, the protein concentration precipitation rate was 67.85% and the protein content was 47.76%. The tea protein contained 18 kinds of amino acid, in which essential amino acids were 40.68%. Amino acid score of tea protein was higher than soybean protein and close to those of breast milk und milk, which indicated that tea protein was one of high quality leaf proteins. This method is easy to operate, low-cost and highly efficient, thereby being suitable for the massive industrial production of tea protein.%以绿茶为原料,采用碱提酸沉的方法提取茶叶蛋白质,以料液比、碱液浓度、温度、时间为考查因素,研究茶叶蛋白质的最佳提取工艺条件,并对提得的茶叶蛋白质进行了氨基酸分析.结果表明:碱提酸沉法提取茶叶蛋白质的最佳工艺条件为料液比1∶25(m/V),碱液浓度03 mol/L,提取温度50℃,提取时间1 h,连续提取两次,茶叶蛋白质的提取率达到85.50%.茶叶蛋白质的最佳等电点为3.0,蛋白质沉淀率为67.85%,粗提取物中蛋白质质量分数为47.76%.氨基酸分析表明:茶叶蛋白质含有18种氨基酸,其中必需氨基酸含量占40.68%;氨基酸评分高于大豆,接近母乳和牛奶,是一种优质的叶蛋白质资源.综合考虑,此方法操作简单,生产成本低,提取效果好,适用于茶叶蛋白质的工业化生产.

  9. 佛山市降水成分及酸雨污染状况分析%Analysis of Components of Precipitation and Pollution Status of Acid Rain in Foshan City

    Institute of Scientific and Technical Information of China (English)

    姚镇; 梁丽红

    2012-01-01

    以“十一五”期间佛山市降水样品监测资料为基础,对佛山市大气降水的离子组成和酸雨污染状况进行了分析,结果表明:佛山市降水pH值较低,酸雨污染较为严重,降水中的主要阳离子是Ca2+和NH4+,主要阴离子为SO4^2-和NO3-,酸雨类型已从单一的硫酸型逐渐转变为硫酸和硝酸混合型。%The ion composition of atmospheric precipitation and the acid rain pollution status of Foshan are studied in this paper on the basis of monitoring data measured during the Eleventh Five Year Plan period. The results show that the pH value of precipitation is low, and the acid rain pollution status is serious; the major cations in precipitation are Ca2+ and NH4+ and the major anions are SO4^2- and NO3^2- ;the acid rain type has been gradually transformed from a single sulfate acid type into the mixed type of sulfuric acid and nitric acid.

  10. Co-precipitation of asiatic acid and poly(l-lactide) using rapid expansion of subcritical solutions into liquid solvents

    Energy Technology Data Exchange (ETDEWEB)

    Sane, Amporn, E-mail: amporn.s@ku.ac.th; Limtrakul, Jumras [Kasetsart University, NANOTEC Center of Excellence, National Nanotechnology Center (Thailand)

    2011-09-15

    Poly(l-lactide) (PLLA) nanoparticles loaded with asiatic acid (AA) were successfully produced by rapid expansion of a subcritical solution into an aqueous receiving solution containing a dispersing agent. A mixture of carbon dioxide (CO{sub 2}) and ethanol (EtOH) with a weight ratio of 1:1 was used as the solvent for AA and PLLA. Two surfactants, Pluronic F127 and sodium dodecyl sulfate were employed. The former was found to be more effective for stabilizing AA-loaded PLLA nanoparticles, as a rapid expansion into a 0.1 wt% Pluronic F127 solution produced a stable nanosuspension consisting mainly of well-dispersed, individual nanoparticles. The effects of rapid expansion-processing conditions-AA to PLLA weight ratio and pre-expansion temperature (T{sub pre})-on the size and morphology of composite nanoparticles, and the loading capacity and entrapment efficiency of AA in PLLA nanoparticles, were systematically investigated. It was found that AA-loaded PLLA nanoparticles with a size range of 30-100 nm were consistently fabricated by rapid expansion at T{sub pre} of 70-100 Degree-Sign C and AA to PLLA weight ratios of 1:2 and 1:4, and with a constant pre-expansion pressure of 330 bar. The T{sub pre} and AA to PLLA weight ratio had no significant effects on the size of the nanoparticles. The AA to PLLA weight ratio is a controlling parameter for both the loading capacity and the entrapment efficiency of AA in PLLA nanoparticles. The loading capacity and entrapment efficiency increased from 8-11 to 16-21 wt%, and 38-57 to 50-62 wt%, respectively, when the AA to PLLA weight ratio changed from 1:4 to 1:2. However, increasing the T{sub pre} from 70 to 100 Degree-Sign C decreased both the loading capacity and entrapment efficiency of AA in PLLA nanoparticles by {approx}20-30%.

  11. Targeted toxicological screening for acidic, neutral and basic substances in postmortem and antemortem whole blood using simple protein precipitation and UPLC-HR-TOF-MS.

    Science.gov (United States)

    Telving, Rasmus; Hasselstrøm, Jørgen Bo; Andreasen, Mette Findal

    2016-09-01

    A broad targeted screening method based on broadband collision-induced dissociation (bbCID) ultra-performance liquid chromatography high-resolution time-of-flight mass spectrometry (UPLC-HR-TOF-MS) was developed and evaluated for toxicological screening of whole blood samples. The acidic, neutral and basic substances covered by the method were identified in postmortem and antemortem whole blood samples from forensic autopsy cases, clinical forensic cases and driving under the influence of drugs (DUID) cases by a reverse target database search. The screening method covered 467 substances. Validation was performed on spiked whole blood samples and authentic postmortem and antemortem whole blood samples. For most of the basic drugs, the established cut-off limits were very low, ranging from 0.25ng/g to 50ng/g. The established cut-off limits for most neutral and acidic drugs, were in the range from 50ng/g to 500ng/g. Sample preparation was performed using simple protein precipitation of 300μL of whole blood with acetonitrile and methanol. Ten microliters of the reconstituted extract were injected and separated within a 13.5min UPLC gradient reverse-phase run. Positive electrospray ionization (ESI) was used to generate the ions in the m/z range of 50-1000. Fragment ions were generated by bbCID. Identification was based on retention time, accurate mass, fragment ion(s) and isotopic pattern. A very sensitive broad toxicological screening method using positive electrospray ionization UPLC-HR-TOF-MS was achieved in one injection. This method covered basic substances, substances traditionally analyzed in negative ESI (e.g., salicylic acid), small highly polar substances such as beta- and gamma-hydroxybutyric acid (BHB and GHB, respectively) and highly non-polar substances such as amiodarone. The new method was shown to combine high sensitivity with a very broad scope that has not previously been reported in toxicological whole blood screening when using only one injection

  12. Catabolic fate of Streptomyces viridosporus T7A-Produced, acid precipitable polymeric lignin upon incubation with ligninolytic Streptomyces species and Phanerochaete chrysosporium

    International Nuclear Information System (INIS)

    Degradation of ground and hot-water-extracted corn stover (Zea mays) lignocellulose by Streptomyces viridosporus T7A generates a water-soluble lignin degradation intermediate termed acid-precipitable polymeric lignin (APPL). The further catabolism of T7A-APPL by S. viridosporus T7A, S. badius 252, and S. setonii75Vi2 was followed for 3 weeks. APPL catabolism by Phanerochaete chrysosporium was followed in stationary cultures in a low-nitrogen medium containing 1% (wt/vol) glucose and 0.05% (wt/vol) T7A-APPL. Metabolism of the APPL was followed by turbidometric assay (600 nm) and by direct measurement of APPL recoverable from the medium. Accumulation and disappearance of soluble low-molecular-weight products of APPL catabolism were followed by gas-liquid chromatography and by high-pressure liquid chromatography, utilizing a diode array detector. Mineralization of a [14C-lignin]APPL was also followed. The percent 14C recovered as 14CO2, 14C-APPL, 14C-labeled water-soluble products, and cell mass-associated radioactivity, were determined for each microorganism after 1 and 3 weeks of incubation in bubbler tube cultures at 370C. P. chrysosporium evolved the most 14CO2, and S. viridosporus gave the greatest decrease in recoverable 14C-APPL. The results show that S. badius was not able to significantly degrade the APPL, while the other microorganisms demonstrated various APPL-degrading abilities

  13. 浸取工艺参数对大豆皮果胶得率和纯度的影响%Effect of Acid Extraction and Alcohol Precipitation Conditions on the Yield and Purity of Soy Hull Pectin

    Institute of Scientific and Technical Information of China (English)

    鲁慧芳; 付苗苗

    2015-01-01

    Soy hull pectin was prepared by hydrochloride acid extraction,followed by alcohol precipitation,and the effect of extracting acid concentration and the pH of precipitating solvent on the yield and purity of pectin were investigated.Strength of acid used for extracting pectin from soy hull and the pH of precipitation had significant effects on the pectin yield.Highest yield of 26%and 28%were obtained when the acid strength was 0.05 mol/L and 0.1 mol/L,respectively,and the pH of the precipitating solution was 3.5.Extraction of pectin with 0.2 mol/L and 0.3 mol/L acid,or precipitation of pectin at pH 2.0,reduced pectin yield.Strength of acid used for extraction or pH of the solution during precipitation did not significantly affect the purity or degree of esterification of the product.Galacturonic acid content and degree of esterification of the products varied from 68%-72%and 56%-60%,respectively.%采用先盐酸浸提然后乙醇沉淀的方法来制备大豆皮,文中主要考察了盐酸的浓度和沉淀剂的pH对果胶得率和纯度的影响.实验结果显示,用盐酸浸提乙醇沉淀法从大豆皮中提取果胶时,盐酸的强度和乙醇的pH对果胶的得率有很显著的影响.在沉淀剂pH为3.5的情况下,当盐酸浓度为0.05 mol/L和0.1 mol/L时,果胶的得率最高,分别为26%和28%.用0.2 mol/L或0.3 mol/L的盐酸浸提果胶或者沉淀体系pH为2.0时,果胶的得率降低.浸提果胶所用酸的强度和沉淀体系的pH对于产品果胶的纯度和酯化度没有显著影响.成品果胶的半乳糖醛酸含量和酯化度分别为68%~72%和56%~60%.

  14. Homogeneous oxalate precipitation of Pu(III)

    International Nuclear Information System (INIS)

    This paper reports on homogeneous oxalate precipitation using diethyl oxalate which was compared to precipitating Pu(III) oxalate with solid oxalic acid. The diethyl oxalate technique at 75 degrees C is better because it gives 50% less plutonium in the filtrate with a reasonable filtering time. Also, the procedure for the homogeneous precipitation is easier to automate because the liquid diethyl oxalate is simpler to introduce into the precipitator than solid oxalic acid. It also provides flexibility because the hydrolysis rate and therefore the precipitation rate can be controlled by varying the temperature

  15. Photocatalytic removal of 2,4-dichlorophenoxyacetic acid herbicide on copper oxide/titanium dioxide prepared by co-precipitation method

    Science.gov (United States)

    Lee, Shu Chin; Hasan, Norhasnita; Lintang, Hendrik O.; Shamsuddin, Mustaffa; Yuliati, Leny

    2016-02-01

    In this work, suppression of the charge recombination on the titanium dioxide (TiO2) was reported by the addition of copper oxide (CuO), which led to a higher activity of TiO2 for removal of 2,4-dichlorophenoxyacetic acid (2,4-D) herbicide. A series of CuO/TiO2 with CuO loadings of 0.1-1 wt% was prepared through a co-precipitation method. X-ray diffraction patterns revealed that the presence of CuO could not be detected as the low loading amount of CuO might have good dispersion on the surface of TiO2. Diffuse reflectance UV-visible spectra suggested that low loading amount of CuO did not influence the optical property of TiO2. Fluorescence spectroscopy revealed that TiO2 possessed a dominant emission peak of 407 nm at an excitation wavelength of 218 nm. The increasing loading amount of CuO decreased the emission intensity of TiO2, suggesting the successful reduction of charge recombination. After irradiation under UV light for 1 h, CuO(0.1 wt%)/TiO2 gave the highest percentage removal of the herbicide among the samples. The optimum loading amount of CuOmight improve the charge separation and reduce the electron-hole recombination on TiO2 without blocking the active sites, thus leading to the improved photocatalytic activity. This work showed that CuO/TiO2 is a potential photocatalyst for environmental remediation.

  16. 金华市酸雨污染现状特征及成因分析%Present State, Characters and Cause of Formation for Acid Precipitation at Jinhua City

    Institute of Scientific and Technical Information of China (English)

    申秀英; 许晓路; 袁向红; 张苗云

    2001-01-01

    It has been indicated by monitoring works that Jinhua city is heavily suffering from acid precipitation. The acid precipitation is characterized by decreased ratio of /, high frequency of occurrence, low pH value. An obvious effect on acid precipitation was found from burning coal, atmospheric cycling, suspension, rain characters and pH value.%根据多年酸雨监测数据,分析了金华市酸雨污染的现状、特征及成因。结果表明,金华市酸雨污染严重,酸雨中/比值逐渐下降;1年中春、冬季酸雨频率高,pH值较低;燃煤、大气环流转换、悬浮物、降雨特征对酸雨率及降水pH均有明显影响。

  17. DISSOLUTION OF PLUTONIUM CONTAINING CARRIER PRECIPITATE BY CARBONATE METATHESIS AND SEPARATION OF SULFIDE IMPURITIES THEREFROM BY SULFIDE PRECIPITATION

    Science.gov (United States)

    Duffield, R.B.

    1959-07-14

    A process is described for recovering plutonium from foreign products wherein a carrier precipitate of lanthanum fluoride containing plutonium is obtained and includes the steps of dissolving the carrier precipitate in an alkali metal carbonate solution, adding a soluble sulfide, separating the sulfide precipitate, adding an alkali metal hydroxide, separating the resulting precipitate, washing, and dissolving in a strong acid.

  18. Broad substrate specificity of phosphotransbutyrylase from Listeria monocytogenes: A potential participant in an alternative pathway for provision of acyl CoA precursors for fatty acid biosynthesis.

    Science.gov (United States)

    Sirobhushanam, Sirisha; Galva, Charitha; Sen, Suranjana; Wilkinson, Brian J; Gatto, Craig

    2016-09-01

    Listeria monocytogenes, the causative organism of the serious food-borne disease listeriosis, has a membrane abundant in branched-chain fatty acids (BCFAs). BCFAs are normally biosynthesized from branched-chain amino acids via the activity of branched chain α-keto acid dehydrogenase (Bkd), and disruption of this pathway results in reduced BCFA content in the membrane. Short branched-chain carboxylic acids (BCCAs) added as media supplements result in incorporation of BCFAs arising from the supplemented BCCAs in the membrane of L. monocytogenes bkd mutant MOR401. High concentrations of the supplements also effect similar changes in the membrane of the wild type organism with intact bkd. Such carboxylic acids clearly act as fatty acid precursors, and there must be an alternative pathway resulting in the formation of their CoA thioester derivatives. Candidates for this are the enzymes phosphotransbutyrylase (Ptb) and butyrate kinase (Buk), the products of the first two genes of the bkd operon. Ptb from L. monocytogenes exhibited broad substrate specificity, a strong preference for branched-chain substrates, a lack of activity with acetyl CoA and hexanoyl CoA, and strict chain length preference (C3-C5). Ptb catalysis involved ternary complex formation. Additionally, Ptb could utilize unnatural branched-chain substrates such as 2-ethylbutyryl CoA, albeit with lower efficiency, consistent with a potential involvement of this enzyme in the conversion of the carboxylic acid additives into CoA primers for BCFA biosynthesis. PMID:27320015

  19. VARIATION AND SOURCE ANALYSIS OF ATMOSPHERIC ORGANIC ACIDS FROM PRECIPITATION AT DINGHU MOUNTAIN%鼎湖山降水有机酸的变化特征及影响因素分析

    Institute of Scientific and Technical Information of China (English)

    龙晓娟; 王雪梅; 朱圣洁; 王跃思; 董汉英; 黄忠良; 陈银洁; 鲍若峪; 吴志勇

    2011-01-01

    针对2009年3月至2010年2月于鼎湖山采集的大气湿沉降进行分析,旨在了解鼎湖山森林生态系统有机酸湿沉降变化特征及其影响因素.结果表明,研究期间鼎湖山甲酸、乙酸和乙二酸的当量平均浓度分别为4.12μeq.L-1、3.39μeq.L-1、2.51μeq.L-1,分别占已测定有机酸的41.1%、33.9%和25.0%;有机酸对降水酸度的总贡献为12.3%;有机酸湿沉降通量呈现湿季(4月—9月)高干季(10月—次年3月)低的季节性变化规律,湿季有机酸湿沉降通量占全年的70.8%.甲酸、乙酸和乙二酸的浓度呈显著正相关,而有机酸与无机离子的相关性不高.利用气团轨迹后推以及天气形势分析发现陆地性降水鼎湖山有机酸浓度略高于海洋性降水,陆地性降水中甲酸、乙酸和乙二酸的当量平均浓度分别为4.47μeq.L-1、3.44μeq.L-1、2.79μeq.L-1,分别是海洋性降水的1.2、1.0和1.2倍;海洋性降水中有机酸沉降负荷大,甲酸、乙酸和乙二酸沉降通量分别是陆地性降水的1.6、1.6和2.1倍.%Precipitation samples obtained from March 2009 to February 2010 at the Dinghu Mountain station,Guangdong Province,were analyzed to study wet deposition of organic acids and their origins.The results showed that the average concentrations of formic acid,acetic acid and oxalic acid were 4.12 μeq·L-1,3.39 μeq·L-1,and 2.51 μeq·L-1,respectively,which contributed to 41.1%,33.9% and 25.0% of total orgaic acids.The contribution of orgaic acids to the total free acidity of precipitation was 12.3%.Wet deposition flux of organic acids in wet seasons was higher than dry season,and contributed to 70.8% of total annual wet-deposition amount.Correlation coefficients among formic acid,acetic acid and oxalic acid were high,while the correlation coefficients with inorganic components were low.The results from back-trajectory analysis indicated that continental precipitation was the primary factor influencing organic acids in

  20. Enhanced insulin sensitivity associated with provision of mono and polyunsaturated fatty acids in skeletal muscle cells involves counter modulation of PP2A.

    Directory of Open Access Journals (Sweden)

    Francesca Nardi

    Full Text Available AIMS/HYPOTHESIS: Reduced skeletal muscle insulin sensitivity is a feature associated with sustained exposure to excess saturated fatty acids (SFA, whereas mono and polyunsaturated fatty acids (MUFA and PUFA not only improve insulin sensitivity but blunt SFA-induced insulin resistance. The mechanisms by which MUFAs and PUFAs institute these favourable changes remain unclear, but may involve stimulating insulin signalling by counter-modulation/repression of protein phosphatase 2A (PP2A. This study investigated the effects of oleic acid (OA; a MUFA, linoleic acid (LOA; a PUFA and palmitate (PA; a SFA in cultured myotubes and determined whether changes in insulin signalling can be attributed to PP2A regulation. PRINCIPAL FINDINGS: We treated cultured skeletal myotubes with unsaturated and saturated fatty acids and evaluated insulin signalling, phosphorylation and methylation status of the catalytic subunit of PP2A. Unlike PA, sustained incubation of rat or human myotubes with OA or LOA significantly enhanced Akt- and ERK1/2-directed insulin signalling. This was not due to heightened upstream IRS1 or PI3K signalling nor to changes in expression of proteins involved in proximal insulin signalling, but was associated with reduced dephosphorylation/inactivation of Akt and ERK1/2. Consistent with this, PA reduced PP2Ac demethylation and tyrosine307phosphorylation - events associated with PP2A activation. In contrast, OA and LOA strongly opposed these PA-induced changes in PP2Ac thus exerting a repressive effect on PP2A. CONCLUSIONS/INTERPRETATION: Beneficial gains in insulin sensitivity and the ability of unsaturated fatty acids to oppose palmitate-induced insulin resistance in muscle cells may partly be accounted for by counter-modulation of PP2A.

  1. 40 CFR 51.117 - Additional provisions for lead.

    Science.gov (United States)

    2010-07-01

    ... smelters, Lead gasoline additive plants, Lead-acid storage battery manufacturing plants that produce 2,000... 40 Protection of Environment 2 2010-07-01 2010-07-01 false Additional provisions for lead. 51.117... Additional provisions for lead. In addition to other requirements in §§ 51.100 through 51.116 the...

  2. 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...

  3. Critical load of acid precipitations. Mapping of Italian regions; Mappa dei carichi critici di acidita' totale riferita al territorio italiano

    Energy Technology Data Exchange (ETDEWEB)

    Bonanni, P.; Brini, S.; Delmonaco, G.; Liburdi, R.; Trocciola, A.; Vetrella, G. [ENEA Centro Ricerche Casaccia, S. Maria di Galeria, RM (Italy). Dipt. Ambiente

    1999-07-01

    In this report the mapping of critical loads of acidity for the Italian terrestrial ecosystems is presented. The level O method (Stockholm Environment Institute) has been used to determine sensitivity to acid deposition; this semi-quantitative method has been modified to address some Italian characteristics. The results show that the sensitivity of the Italian soils to acidification is not particularly elevated: there are really only few small areas with poor tolerance to acid depositions. These areas are in the north-east of Italy, in Alpine and Prealpine region. [Italian] Nel rapporto vengono riportati i risultati della mappatura, riferita agli ecosistemi terrestri del territorio italiano, dei carichi critici per l'acidita' totale. Il calcolo dei carichi critici e' stato eseguito sulla base della metodologia messa a punto dallo Stokholm Environment Institute; a questo metodo semi-quantitativo sono state apportate alcune modifiche per meglio adattarlo alle caratteristiche del territorio italiano. Dall'analisi dei risultati ottenuti, si evince come la sensibilita' dei suoli italiani all'acidificazione non sia particolarmente elevata: sono state riscontrate infatti solo alcune aree, peraltro con superficie limitata, con una scarsa tolleranza alle deposizioni acide. Tali aree sono localizzate nell'Italia nord-orientale, in zona alpina e prealpina.

  4. Targeted toxicological screening for acidic, neutral and basic substances in postmortem and antemortem whole blood using simple protein precipitation and UPLC-HR-TOF-MS

    DEFF Research Database (Denmark)

    Telving, Rasmus; Hasselstrøm, Jørgen Bo; Andreasen, Mette Findal

    2016-01-01

    -HR-TOF-MS was achieved in one injection. This method covered basic substances, substances traditionally analyzed in negative ESI (e.g., salicylic acid), small highly polar substances such as beta- and gamma-hydroxybutyric acid (BHB and GHB, respectively) and highly non-polar substances such as amiodarone. The new method......A broad targeted screening method based on broadband collision-induced dissociation (bbCID) ultra-performance liquid chromatography high-resolution time-of-flight mass spectrometry (UPLC-HR-TOF-MS) was developed and evaluated for toxicological screening of whole blood samples. The acidic, neutral...... was performed on spiked whole blood samples and authentic postmortem and antemortem whole blood samples. For most of the basic drugs, the established cut-off limits were very low, ranging from 0.25ng/g to 50ng/g. The established cut-off limits for most neutral and acidic drugs, were in the range from 50ng...

  5. Automated homogeneous oxalate precipitation of Pu(III)

    International Nuclear Information System (INIS)

    Homogeneous oxalate precipitation using diethyl oxalate was compared to precipitating Pu(III) oxalate with solid oxalic acid. The diethyl oxalate technique at 75 degree C is better because it gives 50% less plutonium in the filtrate with a reasonable filtering time. Also, the procedure for the homogeneous precipitation is easier to automate because the liquid diethyl oxalate is simpler to introduce into the precipitator than solid oxalic acid. It also provides flexibility because the hydrolysis rate and therefore the precipitation rate can be controlled by varying the temperature. 5 refs., 3 figs., 3 tabs

  6. 碱溶酸沉法制备火麻仁蛋白工艺研究%Preparation of semen cannabis protein by alkali-extraction and acid-precipitation

    Institute of Scientific and Technical Information of China (English)

    汤茜

    2011-01-01

    Semen cannabis contains approximately 20%~25% protein including edestin, albumin, and complete proteins easy to be absorbed by human body. In this study, semen cannabis protein was separated by alkali-extraction and acid-precipitation using degreasing semen cannabis as raw material, The optimal technological conditions were obtained by orthogonal experiment as follows: extracting temperature 50℃, alkali-extraction time 0.5h,alkali-extraction pH .11.0, the ratio of solid to liquid 1:20 and acid-precipitation pH 5.0. Under these optimum extraction conditions, the extraction rate of semen cannabis protein reached 29.54%.%火麻仁中大约含20%~25%的蛋白质,主要为麻仁球蛋白和白蛋白,含人体所有必需氨基酸且容易消化的全价蛋白质.该试验以火麻仁为原料,对其进行脱脂处理后,利用碱溶酸沉法制备火麻仁分离蛋白并确定其最佳工艺条件.试验表明,提取温度50℃,碱提时间0.5h,pH 11.0,料液比1∶20,酸沉pH 5.0为最佳工艺条件,在此条件下蛋白质的提取率为29.54%.

  7. 草酸反萃取法直接沉淀负载铈有机相的表征分析%Characterization and Analysis of Direction Extraction and Precipitation of Cerium Loading Organic Phase by Oxalic Acid Solution

    Institute of Scientific and Technical Information of China (English)

    梅燕; 夏川; 陈晓丽; 孙何; 聂祚仁

    2011-01-01

    研究了氢氧化钠介质皂化条件下,用草酸溶液从负载铈的P507有机相中直接反萃取沉淀铈的试验结果.利用红外光谱(IR)、X射线衍射(XRD)、扫描电子显微镜(SEM)及热重-差热分析仪(TG- DSC)等手段,对反萃所得铈沉淀物及最终焙烧产物的物相、形貌和热失重等进行了分析、测试与表征.实验结果表明:沉淀有机相为球形有机铈的配合物,焙烧产物为球形的立方晶系的CeO2晶体,说明前驱物与产物形貌有遗传继承性.IR证实了萃合物的结构与最终CeO2晶体结构完全不同,热重表明吸附水失重为3.5%,所得最终产物的化学组成为CeO2·1/3H2O.%In the condition of sodium hydroxide saponification, the test results using direction extraction and precipitation of cerium from P507 loading organic phase by oxalic acid solution were studied. Infared (IR) spectrum, X-ray diffraction (XRD), transmission electron microscope (TEM) and thermogravimetry (TG-DSC) were used to study and characterize organic cerium precipitates and the final calcined products. The results showed that organic cerium precipitates and final calcined products were spheric organic cerium coordination and spheric cube CeCO2 crystal, respectively, showing their morphologies were successive. IR made out that the structures of organic cerium precipitates and final calcined products were different TG-DSC indicated that the final calcined products weightlessness was 3. 5% and chemical composing was CeO2 ·1/3H2O.

  8. In male rats with concurrent iron and (n-3) fatty acid deficiency, provision of either iron or (n-3) fatty acids alone alters monoamine metabolism and exacerbates the cognitive deficits associated with combined deficiency

    NARCIS (Netherlands)

    Baumgartner, J.; Smuts, C.M.; Malan, L.; Arnold, M.; Yee, B.K.; Bianco, L.E.; Boekschoten, M.V.; Muller, M.R.; Langhans, W.; Hurrell, R.F.; Zimmermann, M.B.

    2012-01-01

    Concurrent deficiencies of iron (Fe) (ID) and (n-3) fatty acids [(n-3)FAD)] in rats can alter brain monoamine pathways and impair learning and memory. We examined whether repletion with Fe and DHA/EPA, alone and in combination, corrects the deficits in brain monoamine activity (by measuring monoamin

  9. In male rats with concurrent iron and (n-3) fatty acid deficiency, provision of either iron or (n-3) fatty acids alone alters monoamine metabolism and exacerbates the cognitive deficits associated with combined deficiency 1-3

    OpenAIRE

    Baumgartner, Jeannine; Smuts, Cornelius M.; Malan, Linda; Arnold, Myrtha; Yee, Benjamin K.

    2012-01-01

    Concurrent deficiencies of iron (Fe) (ID) and (n-3) fatty acids [(n-3)FAD)] in rats can alter brain monoamine pathways and impair learning and memory. We examined whether repletion with Fe and DHA/EPA, alone and in combination, corrects the deficits in brain monoamine activity (by measuring monoamines and related gene expression) and spatial working and reference memory [by Morris water maze (MWM) testing] associated with deficiency. Using a 2 × 2 design, male rats with concurrent ID and (n-3...

  10. The use of dielectric spectroscopy for the characterisation of the precipitation of hydrophobically modified poly(acrylic-acid) with divalent barium ions

    DEFF Research Database (Denmark)

    Christensen, Peter Vittrup; Keiding, Kristian

    2009-01-01

    The use of dielectric spectroscopy as a monitor for coagulation processes was investigated. Hydrophobically modified poly(acrylic-acid) polymers were used as model macromolecules and coagulated with barium ions. The coagulation process was quantified using a photometric dispersion analyser, thereby...... serving as a point of reference for the dielectric spectroscopy. It was found that the hydrophobic modification increased the dosage of barium needed to obtain complete coagulation, whereas the dosage required to initiate coagulation was lowered. The coagulation of the polymer samples caused...... the relaxation time of the measured dielectric dispersion to increase, and this parameter was found to be a good indicator of the formation of polymer aggregates. The magnitude of the dielectric dispersion decreased as a function of barium dosage, but when coagulation was initiated an increase was observed...

  11. 氯气氧化分解草酸钴沉淀母液中的草酸%Oxidation of oxalic acid by chlorine in mother-liquor originated from precipitation of cobalt oxalate

    Institute of Scientific and Technical Information of China (English)

    田庆华; 易宇; 郭学益

    2011-01-01

    为有效去除草酸沉钴母液中残留的大量草酸,采用氯气作为氧化剂探索氧化分解母液中草酸的可行性.考察反应温度、反应时间、氯气用量、搅拌速度和钴离子浓度等因素对氧化效果的影响.确定了优化工艺条件:反应温度50℃,搅拌速度700 r/min,次氯酸钙150 g,6 mol/L盐酸550 mL,反应时间3h.在此条件下,草酸的氧化率可达97.9%,母液中残留的草酸质量浓度仅为0.42 g/L,处理后的母液可直接返回含钴物料的浸出,实现了工艺流程的闭路循环.%In order to remove the oxalic acid left in the mother-liquor originated from the precipitation of cobalt by oxalic acid, a novel method of using chlorine as the oxidant to decompose the oxalic acid was proposed. The main factors affecting the oxidation rate such as the solution temperature, reaction time, quantity of chlorine, stirring speed and Co2* concentration were investigated. The optimal conditions are as follows: 700 r/min of stirring speed, 150 g calcium hypochlorite, 550 mL of hydrochloric acid with concentration of 6 mol/L and 5 h of reaction time at 70 °C. Under these conditions, the oxidation rate of oxalic acid is 97.9% and the concentration of residual oxalic acid in mother liquor is only 0.42 g/L. The treated mother liquor can be returned directly for leaching cobalt. There is a closed circulation in the whole process.

  12. Influence of acid and alkaline sources on optical, structural and photovoltaic properties of CdSe nanoparticles precipitated from aqueous solution

    Science.gov (United States)

    Coria-Monroy, C. Selene; Sotelo-Lerma, Mérida; Hu, Hailin

    2016-06-01

    CdSe is a widely researched material for photovoltaic applications. One of the most important parameters of the synthesis is the pH value, since it determines the kinetics and the mechanism of the reaction and in consequence, the optical and morphological properties of the products. We present the synthesis of CdSe in solution with strict control of pH and the comparison of ammonia and KOH as alkaline sources and diluted HCl as acid medium. CdSe formation was monitored with photoluminescence emission spectra (main peak in 490 nm, bandgap of CdSe nanoparticles). XRD patterns indicated that CdSe nanoparticles are mainly of cubic structure for ammonia and HCl, but the hexagonal planes appear with KOH. Product yield decreases with pH and also decreases with KOH at constant pH value since ammonia has a double function, as complexing agent and alkaline source. Changes in morphology were observed in SEM images as well with the different alkaline source. The effect of alkaline sources on photovoltaic performance of hybrid organic solar cells with CdSe and poly(3-hexylthiophene) as active layers was clearly observed, indicating the importance of synthesis conditions on optoelectronic properties of promising semiconductor nanomaterials for solar cell applications.

  13. Dialysis provision in Malaysia.

    Science.gov (United States)

    Lim, T O; Lee, D G; Zaki, M

    2000-06-01

    We determined the provision for dialysis treatment in Malaysia. There were 181 dialysis centres as at 1st June 1999 (161 Haemodialysis (HD) and 20 Continuous Ambulatory Peritoneal Dialysis (CAPD) centres), providing treatment for 5614 patients. This is equivalent to an estimated prevalence rate of 253 patients per million population (pmp) and new dialysis acceptance rate of 49 patients pmp. Dialysis facilities were widely distributed throughout the country though rather unevenly among states. Penang, Selangor/KL, Malacca led with number of dialysis patients pmp ranging from 417 to 480. Kelantan and Sabah had the lowest provision with 51 and 64 patients pmp respectively. There were more centres and HD capacity in the private sector while the Non-Government Organisation and public sectors had about the same capacity. However the public sector had more patients on account of availability of CAPD and home HD services, as well as low HD capacity to patient ratio. The number ofcentres, HD capacity and patients have increased rapidly especially since 1991; the estimated growth rates were 16.5 centres/year, 658 capacity/year, and 392 patients/year respectively. There was also a trend toward increasing over-capacity in the private and NGO sectors. In conclusion, the level of dialysis provision is increasing, indicating increasing accessibility of dialysis treatment in Malaysia. Over-capacity is a concern in the private and NGO sectors. Thus funding agencies should be encouraged to source provision from those sectors. The public sector still has the crucial role of providing for under-served areas in the country.

  14. RESNA Wheelchair Service Provision Guide

    Science.gov (United States)

    Arledge, Stan; Armstrong, William; Babinec, Mike; Dicianno, Brad E.; Digiovine, Carmen; Dyson-Hudson, Trevor; Pederson, Jessica; Piriano, Julie; Plummer, Teresa; Rosen, Lauren; Schmeler, Mark; Shea, Mary; Stogner, Jody

    2011-01-01

    The purpose of the Wheelchair Service Provision Guide is to provide an appropriate framework for identifying the essential steps in the provision of a wheelchair. It is designed for use by all participants in the provision process including consumers, family members, caregivers, social service and health care professionals, suppliers,…

  15. Understanding Acid Rain

    Science.gov (United States)

    Damonte, Kathleen

    2004-01-01

    The term acid rain describes rain, snow, or fog that is more acidic than normal precipitation. To understand what acid rain is, it is first necessary to know what an acid is. Acids can be defined as substances that produce hydrogen ions (H+), when dissolved in water. Scientists indicate how acidic a substance is by a set of numbers called the pH…

  16. Study on arsenic removal from acid-leaching solution of zinc smelter slag with sulfide precipitation process%锌冶炼废渣浸出液硫化法除砷的研究

    Institute of Scientific and Technical Information of China (English)

    高峰; 贾永忠; 孙进贺; 景燕

    2011-01-01

    A method of using Na2S as precipitation reagent for eliminating arsenic from leaching solution of zinc smelter slag was studied. The effects of acidity, dosages of Na2S, reaction time and so on were investigated.The results indicated that the optimum conductions were as follows: the dosages of Na2S, 16.1 g/L( acid-leaching solution); H2SO4, 3 mol/L; reaction time, 30 min. The arsenic removal rate could reach 99.3% , so the method could prevent AsH3 gas efficiently in the process of extracting of indium.%以硫化钠为沉淀剂,将锌冶炼废渣浸出液中的砷以硫化砷的形式沉淀析出,实验考察了浸出液酸度、硫化钠加入量、反应时间等因素对除砷效率的影响.实验结果表明,当浸出液中游离H2SO4浓度为3 mol/L,Na2S·9H2O投加量为16.1 g/L(浸出液),反应时间为30 min时,浸出液中的砷去除率达到99.3%,较好地解决了在浸出液提铟过程中AsH3气体对环境的污染问题.

  17. Study on process of recovering lead from acid leaching residue by precipitation transformation method%沉淀转化法综合回收酸浸渣中铅的工艺研究

    Institute of Scientific and Technical Information of China (English)

    张福元; 俎小凤; 彭国敏

    2013-01-01

    Comprehensive recovery of low-grade lead in the acid leaching residue from cyanidation process for golden leaching was made through precipitation transformation method.The recovery process was introduced.Influences of factors, such as mass ratio of liquid to solid (L/S), amount of ammonium bicarbonate, and reaction time on converting rate of lead in the reaction process of ammonium bicarbonate and acid leaching residue were also studied through orthogonal tests.The optimum conditions were as follows:mass ratio of L/S was 2.0,amount of ammonium bicarbonate was 30 g,and reaction time was 2.0 h. The transformation ratio of lead reached 97% under those conditions.%通过沉淀转化法对氰化提金工艺酸浸渣中低品位铅进行了综合回收.介绍了回收工艺流程,通过正交实验考察了酸浸渣采用碳酸氢铵转化过程中液固比、碳酸氢铵用量、转化时间等因素对铅转化率的影响,确定了转化反应的最佳条件为:转化液固质量比为2.0、碳酸氢铵用量为30 g、转化时间为2.0 h.在最佳条件下反应,铅转化率可达97%.

  18. 酸性湿沉降对绝缘子闪络特性影响的表征量研究%THE RESEARCH TO TOKEN ON FLASHOVER CHARACTERISTICS OF INSULATOR IN THE ACID WET PRECIPITATION

    Institute of Scientific and Technical Information of China (English)

    余德芬; 孙才新; 顾乐观; 卢至; 司马文霞; 舒立春

    2001-01-01

    针对电力系统近年来大面积污闪事故的新动向,研究了大气环境的酸性湿沉降对绝缘子交流闪络机理、闪络特性的影响。通过试验,得到了绝缘子的交流闪络电压与湿沉降的值及电导率的关系,并探讨了酸性湿沉降环境下绝缘子闪络特性的表征量。%The paper regards to the problem of widespread pollutionflashover happened in power system in the recent year, and studies the AC flashover mechanism and flashover performance of insulators in the acid environment. Through a large of tests, the relation between the AC pollution FOV(flashover voltage) of insulator and the pH as well as conductivity of the wet precipitation is found, the token of flashover performance of insulators in the wet depositions is discussed.

  19. Extraction and Separation of Vitisin D, Ampelopsin B and cis-Vitisin A from Iris lactea Pall. var. chinensis (Fisch.) Koidz by Alkaline Extraction-Acid Precipitation and High-Speed Counter-Current Chromatography.

    Science.gov (United States)

    Lv, Huanhuan; Zhou, Wenna; Wang, Xiaoyan; Wang, Zhenhua; Suo, Yourui; Wang, Honglun

    2016-01-01

    Naturally occurring oligostilbenes are receiving more attention because they exhibit several beneficial effects for health, including hepatoprotective, antitumor, anti-adipogenic, antioxidant, antiaging, anti-inflammatory, anti-microbial, antiviral, immunosuppressive and neuroprotective activities. Thus, they could be of some potentially therapeutic values for several diseases. In this study, we adopted the alkaline extraction-acid precipitation (AEAP) method for extraction of oligostilbenes from the seed kernel of Iris lactea Then, the high-speed counter-current chromatography (HSCCC) was used for preparative isolation and purification of oligostilbenes from the AEAP extracts. Finally, three oligostilbenes, namely vitisin D (73 mg), ampelopsin B (25 mg) and cis-vitisin A (16 mg), were successfully fractionated by HSCCC with a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (2:5:3:6, v/v/v/v) from 300 mg of the AEAP extracts in ∼ 190 min. The purities of the three isolated oligostilbenes were all over 95.0% as analyzed by high performance liquid chromatography. They all were isolated from I. lacteal for the first time.The method of AEAP for the preparation of the oligostilbene-enriched crude sample was simple, and the HSCCC technique for the isolation and purification of oligostilbenes was efficient. PMID:26847919

  20. 利用碱提酸沉法从膨化玉米黄粉中提取谷蛋白%Extraction of gluten from extruded corn gluten meal with alkali-dissolution and acid-precipitation

    Institute of Scientific and Technical Information of China (English)

    张铁; 刘晓兰; 郑喜群

    2012-01-01

    采用碱提酸沉法提取膨化的玉米黄粉谷蛋白,选择碱液浓度、温度、料液比和浸提时间作为因素进行试验.确定最佳提取条件:碱液浓度0.55% (m/V),浸提时间100 min,温度65℃,料液比1∶16(m∶V).该条件下玉米谷蛋白的提取率为50.14%.%The method of alkali-dissolution and acid-precipitation of protein were used to extract gluten from extruded corn gluten meal. The concentration of sodium hydroxide, extracting temperature, the ratio of extruded corn gluten meal to solution of sodium hydroxide, and extracting time were investigated with test of single factor and orthogonal design of Li6(45). Optimized extraction condition were, concentration of sodium hydroxide of 0. 55% (m/V), extracting time of 100 min, temperature of 65℃ and, ratio of solid-liquid of 1 J 16. Under the optimized condition, the yield of gluten was 50. 12%,

  1. Precipitation chemistry in central Amazonia

    Science.gov (United States)

    Andreae, M. O.; Talbot, R. W.; Berresheim, H.; Beecher, K. M.

    1990-01-01

    Rain samples from three sites in central Amazonia were collected over a period of 6 weeks during the 1987 wet season and analyzed for ionic species and dissolved organic carbon. A continuous record of precipitation chemistry and amount was obtained at two of these sites, which were free from local or regional pollution, for a time period of over 1 month. The volume-weighted mean concentrations of most species were found to be about a factor of 5 lower during the wet season compared with previous results from the dry season. Only sodium, potassium, and chloride showed similar concentrations in both seasons. When the seasonal difference in rainfall amount is taken into consideration, the deposition fluxes are only slightly lower for most species during the wet season than during the dry season, again with the exception of chloride, potassium, and sodium. Sodium and chloride are present in the same ratio as in sea salt; rapid advection of air masses of marine origin to the central Amazon Basin during the wet season may be responsible for the observed higher deposition flux of these species. Statistical analysis suggests that sulfate is, to a large extent, of marine (sea salt and biogenic) origin, but that long-range transport of combustion-derived aerosols also makes a significant contribution to sulfate and nitrate levels in Amazonian rain. Organic acid concentrations in rain were responsible for a large fraction of the observed precipitation acidity; their concentration was strongly influenced by gas/liquid interactions.

  2. Behaviour of the pH adjustment, Ion exchange and concentrate precipitation stages in the acid leaching of uranium phosphate ores; Tratamiento de disoluciones de lixiviacion de minerales de uranio en presencia de fosfatos. Comportamiento en las etapas de ajuste de PH, cambio de ion y precipitacion de concentrados

    Energy Technology Data Exchange (ETDEWEB)

    Estrada Aguilar, J.; Uriarte Hueda, A.

    1962-07-01

    The uranium recovery from acid leach solutions of uranium-phosphate ores has been studied. Relations have been found between the solution characteristics and the results obtained at different stages of the process. The following data can thus be predicted: solids to remove and uranium recovery in the pH adjustment stage, uranium capacity of the resin, more suitable eluating agent, elution velocity and uranium concentration in the eluate in the ion exchange stage, and composition of the concentrate produced by direct precipitation of the eluate in the concentrate precipitation stage. (Author) 8 refs.

  3. 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....

  4. Chemisorption And Precipitation Reactions

    Science.gov (United States)

    The transport and bioavailability of chemical components within soils is, in part, controlled by partitioning between solids and solution. General terms used to describe these partitioning reactions include chemisorption and precipitation. Chemisorption is inclusive of the suit...

  5. Storage Gage Precipitation Observations

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A storage gage is a precipitation gage that requires reading and maintenance only monthly or seasonal intervals. This library includes reports from such gages,...

  6. 珠江三角洲滨海小流域离子化学特征及来源分析%Ion Chemistry and Acid Precipitation in a Coastal Watershed in the Pearl River Delta

    Institute of Scientific and Technical Information of China (English)

    谢丽纯; 陈建耀; 董林垚; 蒋华波

    2011-01-01

    Water quality may be influenced by natural inputs and anthropogenic additions via water cycle and mass transportation. Precipitation serves as a major vehicle for dissolved chemical species in addition to the hydrological system. Rainwater, river water and groundwater were collected in the wet (Apr.-Sept.) and dry ( Oct.-Mar. )seasons in 2007, 2009 and 2010. Dissolved concentrations of major ions( Ca2+, Mg2+, Na+, K+, HCO3-, Cl-, SO42-, NO3-, Si) were analyzed, and a simple mass balance was used to calculate contribution ratios of three sources, namely, sea salt deposition, rock weathering and acid precipitation. The total dissolved solids ( TDS ) within the watershed varied from 28.97 to 44.64 mg·L-1, with an average value of 33.90 mg·L-1. And the chemical ion composition of the rivulet water was characterized by dominance of Na+, K+, and HCO3-,C1-. In order to estimate the contribution of sea salt deposition, chloride in the rain water was used as a reference to quantify the portion of the elements carried by rain water. The results show that: the contribution ratios of Ca2+,Mg2+,Na+,K+,SO42- in sea salt deposition were, respectively, 6%, 60%, 47%, 2%, 15% in wet season, and 3%, 41%, 54%, 2%, 10% in dry season. After such corrections, the cations originating from silicate weathering were determined by assuming that there was no direct anthropogenic input to the watershed, and the ratios of ( Ca/Na) Sil and ( Mg/K ) sil were estimated to be 0.31 and 0.21 in wet season, 0.36 and 0.27 in dry season respectively, the CO2 consumption rate by silicate weathering was about 12.4ton·km-2·yr·. NO3- and ( SO42-) res in the rivulet mainly originated from acid precipitation, where their contents in dry season were lower than those in wet season. Because of the acid precipitation and the input of the animal waste, groundwater was polluted, that was proven by the NO3- pollution of well Rl. The lower values of NO3-in wet season suggested that denitrification probably

  7. Caracterização de concentrado protéico de folhas de mandioca obtido por precipitação com calor e ácido Characterization of cassava leaf protein concentrate obtained by heat and acid precipitation

    Directory of Open Access Journals (Sweden)

    Cláudia de Fátima Modesti

    2007-09-01

    Full Text Available As folhas de mandioca apresentam um teor elevado de proteínas, todavia sua digestibilidade é baixa. A produção de concentrado protéico de folhas de mandioca (CPFM permite a utilização das proteínas das folhas com um reduzido teor de fibras e melhor qualidade protéica. Neste trabalho, analisaram-se características químicas de CPFM obtidos por diferentes formas de precipitação, com calor e com ácido. Os CPFM praticamente não apresentaram diferenças na composição centesimal. O nível de proteína dos CPFM aumentou 57,72% em comparação ao da farinha de folhas de mandioca (FFM. Os rendimentos de extração das proteínas também foram semelhantes para os CPFM. O teor de Fe dos CPFM foi mais elevado quando comparado com o da FFM. A FFM apresentou absorção de água e de óleo mais elevada que os CPFM, mas, entre os tipos de CPFM, os resultados foram semelhantes. A mínima solubilidade de nitrogênio da FFM e dos CPFM foi observada em pH entre 3 e 5. Verificou-se que a FFM apresentou uma capacidade de formação e estabilidade de espuma mais elevada que os CPFM. Tanto a FFM quanto os CPFM não apresentaram boa estabilidade de emulsão.Cassava leaves have a high content of protein of low digestibility. The production of cassava leaf protein concentrate (CLPC enables cassava leaf protein to be used with a reduced fiber content and better protein quality. This work involved an investigation of the chemical characteristics of CLPC produced by different forms of precipitation, using heat and acid. No significant differences were found in the centesimal composition of the CLPC. The protein content in CLPC was 57.72% higher than in cassava leaf flour (CLF. Both types of CLPC precipitation also yielded similar protein concentrations. The CLPC Fe content was higher than that of the CLF. The CLF presented higher water and oil absorption than did CLPC, although the CLPC extracted by the two methods showed similar results. The lowest nitrogen

  8. Ecological impact of acid precipitation. [Lead abstract

    Energy Technology Data Exchange (ETDEWEB)

    Drabloes, D.; Tollan, A. (eds.)

    1980-10-01

    Separate abstracts were prepared for 134 of the papers presented in these proceedings. Investigations into: transport and deposition, vegetation and soils, water quality, aquatic biota, impacts on soils and indirect effects on vegetation, effects on water quality, effects on aquatic biota, and various integrated studies are all discussed. Six papers were previously input to the data base.

  9. Quantitative Determination of Free Polysaccharide Content in Haemophilus influenzae Type b Conjugate Vaccine by Acid Precipitation with Sodium Deoxycholate%脱氧胆酸钠酸沉淀法定量测定b型流感嗜血杆菌结合疫苗中游离多糖的含量

    Institute of Scientific and Technical Information of China (English)

    袁军; 李新国; 瞿明霞

    2011-01-01

    目的 建立一种b型流感嗜血杆菌(Haemophilus influenzae type b,Hib)结合疫苗中游离多糖含量新的检测方法.方法 分别对标准蛋白溶液、多糖溶液和标加衍生多糖(A H-PRP)的结合物原液进行脱氧胆酸钠(NaDC)酸沉淀处理,观察该方法 对蛋白和多糖的沉淀效果.分别采用NaDC酸沉淀法和乙醇分步沉淀法测定结合疫苗原液中的游离多糖含量.结果 不同浓度的标准蛋白溶液经NaDC酸沉淀法处理后,沉淀中蛋白的回收率在96%~ 99%之间;不同浓度的多糖溶液经NaDC酸沉淀法处理后,上清中的多糖回收率在99%~106%之间;该方法 对结合物中的游离多糖能起到很好的分离效果;两种方法 测定结合疫苗原液中的游离多糖含量差异有统计学意义(P<0.01).结论 NaDC酸沉淀法能专一性地沉淀蛋白物质,对游离多糖无沉淀作用,该方法 具有良好的重复性和准确性,可用于测定Hib结合疫苗中的游离多糖含量.%Objective To develop a novel method for determination of free polysaccharide content in Haemophilus influenzae type b (Hib) conjugate vaccine. Methods Standard protein solution, polysaccharide solution and bulk of conjugate added with polysaccharide derivative were treated by acid precipitation with sodium deoxycholate (NaDC ) and observed for precipitation effect of protein and polysaccharide. The free polysaccharide content in bulk of conjugate vaccine was determined by acid precipitation with NaDC and fractional precipitation with ethanol respectively. Results After acid precipitation with NaDC, the recovery rates of protein in precipitate of standard protein solution at various concentrations were 96% ~ 99%, while those of polysaccharide in supernatant of polysaccharide solution were 99% ~ 106%. The free polysaccharide in conjugate was effectively separated by the developed method. The free polysaccharide contents in bulk of conjugate vaccine determined by acid

  10. Microbially Induced Precipitation of Strontianite Nanoparticles.

    Science.gov (United States)

    Kang, Serku; Yumi Kim; Lee, Young Jae; Roh, Yul

    2015-07-01

    The objectives of this study were to investigate the microbially mediated precipitation of strontium by microorganisms, and to examine the mineralogical characteristics of the precipitates. Wu Do-1 (Proteus mirabilis) enriched from rhodoliths was used to precipitate strontium at room temperature under aerobic environment. The growth of Wu Do-1 gradually increased over 16 days (OD600 = 2.6) and then decreased until 22 days (OD600 = 2.0) during microbial incubation for strontium precipitation. Also, the pH decreased from 6.5 to 5.3 over 4 days of incubation due to microbial oxidation of organic acids, and then the pH increased up to 8.6 at 25 days of incubation due to NH3+ generation. The Sr2+ concentration in the biotic group sharply decreased from 2,953 mg/L to 5.7 mg/L over 29 days of incubation. XRD, SEM-/TEM-EDS analyses revealed that the precipitates formed by Wu Do-1 (Proteus mirabilis) were identified as 20-70 nm sized strontianite (SrCO3). Therefore, these results suggested that formation of sparingly soluble Sr precipitates mediated by Wu Do-1 (Proteus mirabilis) sequesters strontium and carbon dioxide into a more stable and less toxic form such as strontianite (SrCO3). These results also suggest that bioremediation of metal-contaminated water and biominealization of carbonate minerals may be feasible in the marine environment.

  11. The Frontier Between Adsorption and Precipitation of Polyacrylic Acid on Calcium Carbonate Frontière entre adsorption et précipitation de l'acide polyacrylique sur le carbonate de calcium

    Directory of Open Access Journals (Sweden)

    Cabane B.

    2006-12-01

    Full Text Available Adsorption of polymers on mineral surfaces allowing colloidal stability have widespread applications in industrial processes. The binding mechanism has been quite well described on oxide surfaces. Mainly in terms of hydrogen bonds and electrostatic interactions between charged sites and polymer segments. This phenomenon has been modelized and the influence of pH. Ionic strentgh, and molecular weight can be calculated or predicted. In the case of sparingly soluble substrates such as BaSO4, CaCO3 or CaSO4, several problems arise : the difficulty for the identification of surface sites and the interference of ions coming from the material's solubility. In the case of calcite, the solubility imposes dissolved calcium ions in solution which could complex the polyelectrolyte and reduce its solubility. For that purpose, we have measured the binding energy using microcalorimetry. Microcalorimetric measurements have shown that the adsorption enthalpy is weakly enclothermic: about + 2 kj/mol. Interestingly, this value is very closed to that of calcium complexation with PANa. It is suggested that the driving force for adsorption is the net gain in entropy of the system. The microcalorimetric adsorption isotherm does not show any evidence for a strongly exothermic interaction between positive edges and negative segment of the polyion. Practically, in most cases, adsorption of polymers is calculated from the decrease of its concentration in the solution after separation of the solid by centrifugation. This procedure does not discriminate therefore between real adsorption and phase separation. To answer the question, we have performed adsorption experiments using a dialysis membrane to separate the solid particles from the solution. It has been established that in some circumstances, depending on the relative amount of calcite, calcium ions and polyelectrolyte, precipitation takes place rather than adsorption. This is especially the case at low polymer

  12. Precipitating factors of asthma.

    Science.gov (United States)

    Lee, T H

    1992-01-01

    Asthma is characterised by bronchial hyperresponsiveness. This feature of the asthmatic diathesis predisposes patients to wheezing in response to a number of different factors. These precipitating factors include specific allergen acting via sensitised mediator cells through an IgE-dependent mechanism. There are irritants which may work through a non-specific manner, or stimuli such as exercise and hyperventilation, which probably also act through mediator release via a non-IgE-dependent manner. The mechanism whereby physical stimuli such as exercise induce bronchoconstriction is of interest, because it increases the context in which the mast cell may participate in acute asthmatic bronchoconstriction. Respiratory infections also commonly provoke asthma, especially in infants and may, indeed, precipitate the asthmatic state itself. Finally, drugs can often trigger asthma attacks and the mechanisms of asthma precipitated by non-steroidal anti-inflammatory drugs such as aspirin have been the subject of recent research.

  13. Hydrolysis of precipitated phytate by three distinct families of phytases

    OpenAIRE

    Lim, BL; Tang, J; Leung, A.; Leung, C

    2006-01-01

    While genetically modified plants that secrete histidine acid phosphatases (HAPs), β-propeller phytases (BPPs) and purple acid phosphatases (PAPs) have been shown to assimilate soluble phytate, little is known about whether these plants have the ability to hydrolyze precipitated phytate. In this study, the ability of representative members of these three classes of phytases to hydrolyze metal-phytate salts and to hydrolyze phytate adsorbed to aluminum precipitates was compared. All three phyt...

  14. From precipitation to stream

    OpenAIRE

    Peralta-Tapia, Andres

    2015-01-01

    Understanding the journey water makes from precipitation entering a catchment, traveling through soils, and the time it takes before it exits as stream water are questions of great relevance for both scientists and environmental managers. Natural stable isotopes such as δ¹⁸O and δ²H have been extensively used over the last decades to trace water through diverse catchments across the world. In this thesis I analyzed over 2500 isotope samples to create long-term time series of precipitation and...

  15. Hybrid resource provisioning for clouds

    International Nuclear Information System (INIS)

    Flexible resource provisioning, the assignment of virtual machines (VMs) to physical machine, is a key requirement for cloud computing. To achieve 'provisioning elasticity', the cloud needs to manage its available resources on demand. A-priori, static, VM provisioning introduces no runtime overhead but fails to deal with unanticipated changes in resource demands. Dynamic provisioning addresses this problem but introduces runtime overhead. To reduce VM management overhead so more useful work can be done and to also avoid sub-optimal provisioning we propose a hybrid approach that combines static and dynamic provisioning. The idea is to adapt a good initial static placement of VMs in response to evolving load characteristics, using live migration, as long as the overhead of doing so is low and the effectiveness is high. When this is no longer so, we trigger a revised static placement. (Thus, we are essentially applying local multi-objective optimization to tune a global optimization with reduced overhead.) This approach requires a complicated migration decision algorithm based on current and predicted:future workloads, power consumptions and memory usage in the host machines as well as network burst characteristics for the various possible VM multiplexings (combinations of VMs on a host). A further challenge is to identify those characteristics of the dynamic provisioning that should trigger static re-provisioning.

  16. Optimal Provision of Public Goods

    DEFF Research Database (Denmark)

    Kreiner, Claus Thustrup; Verdelin, Nicolaj

    2012-01-01

    The standard approach to the optimal provision of public goods highlights the importance of distortionary taxation and distributional concerns. A new approach neutralizes distributional concerns by adjusting the income tax schedule. We demonstrate that both approaches are derived from the same...... of optimal provision are different, and the modified Samuelson rule is likely to lead to underprovision...

  17. 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...

  18. Effect of transglutaminase on yield of proteins extracted from whole Antarctic krill(Euphausia superba) by alkaline solubilization and acid precipitation method%谷氨酰胺转氨酶对碱溶酸沉法提取南极磷虾(Euphausia superba)蛋白质得率的影响

    Institute of Scientific and Technical Information of China (English)

    王灵昭; 薛长湖; 王玉明; 薛勇

    2012-01-01

    Alkaline solubilization and acid precipitation method was employed to extract proteins from whole Antarctic krill(Euphausia superba),and effect of transglutaminase on protein recovery yield was researched.Results indicated that the alkaline solubilization and acid precipitation method was good at recovering protein from whole Antarctic krill,and protein recovery yield was increased by approximate 5%,when transglutaminase was correctly applied during acid-induced protein precipitation.%通过碱溶酸沉法提取了南极磷虾蛋白质,研究了谷氨酰胺转氨酶的应用对蛋白质得率的影响。结果表明:碱溶酸沉法能够较好地回收南极磷虾蛋白质;在酸沉过程中,合理添加谷氨酰胺转氨酶能够提高蛋白质得率约5%。

  19. Parametric study on co-precipitation of U/Th in MOX fuel of AHWR

    International Nuclear Information System (INIS)

    During manufacturing of Mixed Oxide Fuel (MOX) pellets for Advance Heavy Water Reactor (AHWR-LEU), around 30% rejected MOX pellets are generated in every cycle. These rejected MOX pellets are dissolved in nitric acid for recovery of U/Th. The recovered U/Th is recycled for production of MOX pellets. MOX pellets of varying compositions are used in AHWR fuel. Dissolution of MOX pellets in nitric acid is a challenging task because of its low surface area and longer dissolution times. High normal nitric acid is used in order to increase rate of dissolution, which in turn results in generation of high free acidity solution which influences the precipitation characteristics of Uranium (VI) by oxalic acid. Oxalic acid precipitation helps in generation of nitric acid which can be used for dissolution there by effectively facilitating nil effluent generation. Precipitation by oxalic acid unlike ammonia has advantage of zero liquid effluent discharge by complete recycle of oxalate filtrate to dissolution section. In the present work, the effect of various parameters like free acidity, residence time, concentration of oxalic acid, initial concentration of uranium and thorium etc. on the precipitation of U(VI) and Th(IV) in nitrate media by oxalic acid was carried out. The precipitated powder was subjected to various morphological evaluations like particle size etc. Study of various parameters on the co-precipitation of uranium and thorium by oxalic acid was carried out. It was observed that complete precipitation (> 99.9%) of thorium as oxalate does not depend on free acidity range (1- 6 N). Excess oxalic acid is not required for complete precipitation of thorium oxalate. The precipitation of uranyl oxalate varies with initial free acidity of solution. Uranyl oxalate precipitation does not take place at and above 5 N of free acidity

  20. 48 CFR 217.7601 - Provisioning.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Provisioning. 217.7601... Provisioning Requirements 217.7601 Provisioning. (a) Follow the procedures at PGI 217.7601 for contracts with provisioning requirements. (b) For technical requirements of provisioning, see DoD 4140.1-R, DoD Supply...

  1. Chemical compositions of precipitation and scavenging of particles in Beijing

    Institute of Scientific and Technical Information of China (English)

    HU Min; ZHANG Jing; WU Zhijun

    2005-01-01

    Totally 23 precipitation samples were collected in Beijing from May to November in 2003. In order to investigate the chemical composition of precipitation samples, pH, conductivity, concentrations of water-soluble ions and organic acids were analyzed. The average pH of precipitations is 6.18, belonging to the neutral range; the average conductivity is 52.23 (S/cm, which indicates that precipitations in Beijing are obviously polluted; are the most abundant anions with the average concentrations of 521 and 174 μeq·L-1, respectively; the average equivalent ratio is 3.1, which decreases by about 15% compared with the result of 1994; and Ca2+ are the most abundant cations with the average concentrations of 376 and 397 μeq·L-1, respectively; formic acid, acetic acid and oxalic acid are the main organic acids with the average concentrations of 4.62, 4.60 and 1.17 μeq·L-1, respectively, accounting for 2% of the overall anions. Obvious differences between concentrations before and after precipitation are also observed by SJAC (Steam Jet Aerosol Collector), which shows the removal of particles from the atmosphere by precipitation.

  2. Status of satellite precipitation retrievals

    Directory of Open Access Journals (Sweden)

    C. Kidd

    2011-04-01

    Full Text Available Satellites offer an unrivalled vantage point to observe and measure Earth system processes and parameters. Precipitation (rain and snow in particular, benefit from such observations since precipitation is spatially and temporally highly variable and with satellites overcoming some of the deficiencies of conventional gauge and radar measurements. This paper provides an overall review of quantitative precipitation estimation, covering the basis of the satellite systems used in the observation of precipitation, the dissemination and processing of this data, and the generation, availability and validation of these precipitation estimates. A selection of applications utilising these precipitation estimates are then outlined to exemplify the utility of such products.

  3. ANALYTICAL CHARACTERIZATION OF PRECIPITATIONS

    Directory of Open Access Journals (Sweden)

    Danut Tiberiu Epure

    2011-02-01

    Full Text Available The properties of precipitation are mainly determined by solid, liquid and gaseous substances that exist in suspended or dissolved form. These substances come from many complex interactions between the atmosphere – hydrosphere – lithosphere – biota. The analytical characterization of precipitation has been based on the analysis of several chemical parameters: pH, conductivity, chloride, fluoride and ammonium ions, total hardness, alkalinity, H2S and sulphides, COD (Mn, nitrites, phosphorous, metallic ions (total iron, copper and chromium. In this purpose were collected rainwater, ice and snow from different areas (cities Năvodari, Constanţa, Buzău and Mihail Kogălniceanu during November 2007 till February 2008. This study shows that chemical characteristics of the analyzed water samples vary from one region to another depending on the mineralogical composition of zones crossed, the contact time, temperature, weather conditions, the sampling period (day or night and the nature of sample (rain, snow, ice.

  4. 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...

  5. Modeling solid-state precipitation

    CERN Document Server

    Nebylov, AlexanderKozeschnik, Ernst

    2012-01-01

    Over recent decades, modeling and simulation of solid-state precipitation has attracted increased attention in academia and industry due to their important contributions in designing properties of advanced structural materials and in increasing productivity and decreasing costs for expensive alloying. In particular, precipitation of second phases is an important means for controlling the mechanical-technological properties of structural materials. However, profound physical modeling of precipitation is not a trivial task. This book introduces you to the classical methods of precipitation model

  6. Precipitation Indices Low Countries

    Science.gov (United States)

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

    2009-09-01

    Since 1995, KNMI published a series of books(1), presenting an annual reconstruction of weather and climate in the Low Countries, covering the period AD 763-present, or roughly, the last millennium. The reconstructions are based on the interpretation of documentary sources predominantly and comparison with other proxies and instrumental observations. The series also comprises a number of classifications. Amongst them annual classifications for winter and summer temperature and for winter and summer dryness-wetness. The classification of temperature have been reworked into peer reviewed (2) series (AD 1000-present) of seasonal temperatures and temperature indices, the so called LCT (Low Countries Temperature) series, now incorporated in the Millennium databases. Recently we started a study to convert the dryness-wetness classifications into a series of precipitation; the so called LCP (Low Countries Precipitation) series. A brief outline is given here of the applied methodology and preliminary results. The WMO definition for meteorological drought has been followed being that a period is called wet respectively dry when the amount of precipitation is considerable more respectively less than usual (normal). To gain a more quantitative insight for four locations, geographically spread over the Low Countries area (De Bilt, Vlissingen, Maastricht and Uccle), we analysed the statistics of daily precipitation series, covering the period 1900-present. This brought us to the following definition, valid for the Low Countries: A period is considered as (very) dry respectively (very) wet if over a continuous period of at least 60 days (~two months) cq 90 days (~three months) on at least two out of the four locations 50% less resp. 50% more than the normal amount for the location (based on the 1961-1990 normal period) has been measured. This results into the following classification into five drought classes hat could be applied to non instrumental observations: Very wet period

  7. Status of satellite precipitation retrievals

    Directory of Open Access Journals (Sweden)

    C. Kidd

    2010-10-01

    Full Text Available Satellites offer an unrivalled vantage point to observe and measure Earth system processes and parameters. Precipitation (rain and snow in particular, benefit from such observations since precipitation is spatially and temporally highly variable and overcomes some of the deficiencies of conventional gauge and radar measurements. This paper provides an overall review of quantitative precipitation estimation, covering the basis of the satellite systems used in the observation of precipitation and the dissemination of this data, the processing of these measurements to generate the rainfall estimates and the availability, verification and validation of these precipitation estimates.

  8. Characterisation of Suspension Precipitated Nanocrystalline Hydroxyapatite Powders

    Science.gov (United States)

    Mallik, P. K.; Swain, P. K.; Patnaik, S. C.

    2016-02-01

    Hydroxyapatite (HA) is a well-known biomaterial for coating on femoral implants, filling of dental cavity and scaffold for tissue replacement. Hydroxyapatite possess limited load bearing capacity due to their brittleness. In this paper, the synthesis of nanocrystalline hydroxyapatite powders was prepared by dissolving calcium oxide in phosphoric acid, followed by addition of ammonia liquor in a beaker. The prepared solution was stirred by using magnetic stirrer operated at temperature of 80°C for an hour. This leads to the formation of hydroxyapatite precipitate. The precipitate was dried in oven for overnight at 100°C. The dried agglomerated precipitate was calcined at 800°C in conventional furnace for an hour. The influence of calcium oxide concentration and pH on the resulting precipitates was studied using BET, XRD and SEM. As result, a well-defined sub-rounded morphology of powders size of ∼41 nm was obtained with a salt concentration of 0.02 M. Finally, it can be concluded that small changes in the reaction conditions led to large changes in final size, shape and degree of aggregation of the hydroxyapatite particles.

  9. Kosa (yellow sand) components in precipitation collected at central Japan

    Institute of Scientific and Technical Information of China (English)

    Chohji Tetsuji; Kitamura Moritsugu; Tabata Masahiro

    2002-01-01

    In east Asia, acidic gases derived from fossil fuel combustion have increased in the pastdecades. On the other hand, the Asian dust, also called Kosa (yellow sand) is transported follow-ing windstorms from arid lands in the Asian continent. Many researchers have been interested inthe reaction between acidic aerosols and Kosa aerosols as well as the long-range transport ofthese emissions. To investigate the characteristics of chemical components in precipitation on along-term basis over Japan, precipitation was sequentially collected from April 1984 to March 1997at Kanazawa located near the coast of the Sea of Japan. Precipitation samples were collected at 1mm intervals for the first 5 mm rainfall and all volume of rainwater after 6 mm for all precipitationevents with an automatic wet only precipitation collector. According to the analyses of precipitationincluding Kosa aerosols during Kosa periods, the reaction in the air between Kosa and acidiccomponents during the long-range transport was discussed.

  10. Models of Public Service Provision

    DEFF Research Database (Denmark)

    Andersen, Lotte Bøgh; Kristensen, Nicolai; Pedersen, Lene Holm

    2013-01-01

    This article extends the framework of Le Grand (2003, 2010) to encompass responsiveness, and the main argument is that the combination of employee motivation, user capacity, and models of public service provision potentially has serious implications for responsiveness across service areas. Although...... research on employee motivation thrives, especially in the public service motivation (PSM) literature, few studies have investigated user capacity empirically, and we know little about the combination of PSM, user capacity and models of service provision. Analyzing four central service areas (day care......, schools, hospitals, and universities), we find variations in both user capacity and PSM. Taking this variation as a point of departure we discuss what implications different combinations of employee motivation, user capacity, and models of public service provision may have for responsiveness....

  11. 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.

  12. Provisions accountancy for pensions and similar liabilities

    OpenAIRE

    MIHAELA COSMINA PETRE

    2012-01-01

    The foundation of accountancy provisions is based on IAS 37 „Provisions, Contingent Liabilities and Contingent Assets” and on „European Accountancy Regulations” aproved by OMFP no.3055/2009. The main problems regarding the provisions normalization and reglementation by using the mentioned sources of accountancy law refer to: provisions definition and delimitation, their acknowledgement, evaluation, modification and accounting. Pension provisions refer to the amount to be paid by the entity af...

  13. Dynamic provisioning for community services

    CERN Document Server

    Qi, Li

    2013-01-01

    Dynamic Provisioning for Community Services outlines a dynamic provisioning and maintenance mechanism in a running distributed system, e.g. the grid, which can be used to maximize the utilization of computing resources and user demands. The book includes a complete and reliable maintenance system solution for the large-scale distributed system and an interoperation mechanism for the grid middleware deployed in the United States, Europe, and China. The experiments and evaluations have all been practically implemented for ChinaGrid, and the best practices established can help readers to construc

  14. Optimal Provision of Public Goods

    DEFF Research Database (Denmark)

    Kreiner, Claus Thustrup; Verdelin, Nicolaj

    2009-01-01

    There currently exist two competing approaches in the literature on the optimal provision of public goods. The standard approach highlights the importance of distortionary taxation and distributional concerns. The new approach neutralizes distributional concerns by adjusting the non-linear income...... for the optimal level of a public good without imposing strong assumptions on preferences. This formula shows that distortionary taxation may have a role to play as in the standard approach. However, the main determinants of optimal provision are completely different and the traditional formula with its emphasis...

  15. PYROLYSIS KINETICS OF WASHED PRECIPITATED LIGNIN

    Directory of Open Access Journals (Sweden)

    Christina Gustafsson

    2009-02-01

    Full Text Available This article describes the pyrolysis behavior of precipitated washed lignin in a Laminar Entrained Flow Reactor between 700 and 1000°C and at different residence times. Lignin was precipitated by acidification of softwood black liquor using CO2. After acid washing, the solid material was dried and sieved (80-100 μm. This material was then fed into the reactor at a rate of about 0.1 g/min. The formed gases were analyzed with respect to CO, CO2, and CH4, and char was collected and weighed. A traditional first order Arrhenius kinetic expression, based on the temperature of the particles with respect to residence time, was adapted to the experimental results. The activation energy was found to be 32.1 kJ/mol. The low ash content in the washed lignin gave a very low solid material residue after the reactor.

  16. Precipitation extremes under climate change

    CERN Document Server

    O'Gorman, Paul A

    2015-01-01

    The response of precipitation extremes to climate change is considered using results from theory, modeling, and observations, with a focus on the physical factors that control the response. Observations and simulations with climate models show that precipitation extremes intensify in response to a warming climate. However, the sensitivity of precipitation extremes to warming remains uncertain when convection is important, and it may be higher in the tropics than the extratropics. Several physical contributions govern the response of precipitation extremes. The thermodynamic contribution is robust and well understood, but theoretical understanding of the microphysical and dynamical contributions is still being developed. Orographic precipitation extremes and snowfall extremes respond differently from other precipitation extremes and require particular attention. Outstanding research challenges include the influence of mesoscale convective organization, the dependence on the duration considered, and the need to...

  17. Bereavement Care Provision in Europe

    DEFF Research Database (Denmark)

    Guldin, Mai-Britt; Murphy, Irene; Keegan, Orla;

    2015-01-01

    The Bereavement Care Taskforce of the EAPC has conducted a survey on bereavement care service provision in Europe. Mai-Britt Guldin, Irene Murphy, Orla Keegan, Barbara Monroe, Maria Antonia Lacasta Reverte and Inger Benkel report on the results. One of the key findings is that not all palliative...

  18. Inclusive Education: Programmes and Provisions

    Science.gov (United States)

    Kappen, Mini Dejo

    2010-01-01

    Inclusive education is a practice of teaching handicapped children in regular classrooms with non-handicapped children to the fullest extent possible; such children may have orthopedic, intellectual, emotional, or visual difficulties or handicaps associated with hearing or learning. In India there are constitutional provisions for Inclusive…

  19. Social Housing Provision in Copenhagen

    DEFF Research Database (Denmark)

    Tsenkova, Sasha; Vestergaard, Hedvig

    The paper provides an overview of trends and processes of change affecting new social housing provision in Denmark with a focus on Copenhagen. The local responses are reviewed within the context of changes to the unitary national housing system that functions with a robust range of private and non-profit...

  20. Status of satellite precipitation retrievals

    OpenAIRE

    Kidd, C.; V. Levizzani

    2010-01-01

    Satellites offer an unrivalled vantage point to observe and measure Earth system processes and parameters. Precipitation (rain and snow) in particular, benefit from such observations since precipitation is spatially and temporally highly variable and overcomes some of the deficiencies of conventional gauge and radar measurements. This paper provides an overall review of quantitative precipitation estimation, covering the basis of the satellite systems used in the observation of precipi...

  1. 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

  2. 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

  3. Inducing mineral precipitation in groundwater by addition of phosphate

    Directory of Open Access Journals (Sweden)

    Hartmann Thomas

    2011-10-01

    Full Text Available Abstract Background Induced precipitation of phosphate minerals to scavenge trace elements from groundwater is a potential remediation approach for contaminated aquifers. The success of engineered precipitation schemes depends on the particular phases generated, their rates of formation, and their long term stability. The purpose of this study was to examine the precipitation of calcium phosphate minerals under conditions representative of a natural groundwater. Because microorganisms are present in groundwater, and because some proposed schemes for phosphate mineral precipitation rely on stimulation of native microbial populations, we also tested the effect of bacterial cells (initial densities of 105 and 107 mL-1 added to the precipitation medium. In addition, we tested the effect of a trace mixture of propionic, isovaleric, formic and butyric acids (total concentration 0.035 mM. Results The general progression of mineral precipitation was similar under all of the study conditions, with initial formation of amorphous calcium phosphate, and transformation to poorly crystalline hydroxylapatite (HAP within one week. The presence of the bacterial cells appeared to delay precipitation, although by the end of the experiments the overall extent of precipitation was similar for all treatments. The stoichiometry of the final precipitates as well as Rietveld structure refinement using x-ray diffraction data indicated that the presence of organic acids and bacterial cells resulted in an increasing a and decreasing c lattice parameter, with the higher concentration of cells resulting in the greatest distortion. Uptake of Sr into the solids was decreased in the treatments with cells and organic acids, compared to the control. Conclusions Our results suggest that the minerals formed initially during an engineered precipitation application for trace element sequestration may not be the ones that control long-term immobilization of the contaminants. In

  4. Air toxics provisions of the Clean Air Act: Potential impacts on energy

    Energy Technology Data Exchange (ETDEWEB)

    Hootman, H.A.; Vernet, J.E.

    1991-11-01

    This report provides an overview of the provisions of the Clean Air Act and its Amendments of 1990 that identify hazardous air pollutant (HAP) emissions and addresses their regulation by the US Environmental Protection Agency (EPA). It defines the major energy sector sources of these HAPs that would be affected by the regulations. Attention is focused on regulations that would cover coke oven emissions; chromium emission from industrial cooling towers and the electroplating process; HAP emissions from tank vessels, asbestos-related activities, organic solvent use, and ethylene oxide sterilization; and emissions of air toxics from municipal waste combustors. The possible implications of Title III regulations for the coal, natural gas, petroleum, uranium, and electric utility industries are examined. The report discusses five major databases of HAP emissions: (1) TRI (EPA`s Toxic Release Inventory); (2) PISCES (Power Plant Integrated Systems: Chemical Emissions Studies developed by the Electric Power Research Institute); (3) 1985 Emissions Inventory on volatile organic compounds (used for the National Acid Precipitation Assessment Program); (4) Particulate Matter Species Manual (EPA); and (5) Toxics Emission Inventory (National Aeronautics and Space Administration). It also offers information on emission control technologies for municipal waste combustors.

  5. Air toxics provisions of the Clean Air Act: Potential impacts on energy

    Energy Technology Data Exchange (ETDEWEB)

    Hootman, H.A.; Vernet, J.E.

    1991-11-01

    This report provides an overview of the provisions of the Clean Air Act and its Amendments of 1990 that identify hazardous air pollutant (HAP) emissions and addresses their regulation by the US Environmental Protection Agency (EPA). It defines the major energy sector sources of these HAPs that would be affected by the regulations. Attention is focused on regulations that would cover coke oven emissions; chromium emission from industrial cooling towers and the electroplating process; HAP emissions from tank vessels, asbestos-related activities, organic solvent use, and ethylene oxide sterilization; and emissions of air toxics from municipal waste combustors. The possible implications of Title III regulations for the coal, natural gas, petroleum, uranium, and electric utility industries are examined. The report discusses five major databases of HAP emissions: (1) TRI (EPA's Toxic Release Inventory); (2) PISCES (Power Plant Integrated Systems: Chemical Emissions Studies developed by the Electric Power Research Institute); (3) 1985 Emissions Inventory on volatile organic compounds (used for the National Acid Precipitation Assessment Program); (4) Particulate Matter Species Manual (EPA); and (5) Toxics Emission Inventory (National Aeronautics and Space Administration). It also offers information on emission control technologies for municipal waste combustors.

  6. Air toxics provisions of the Clean Air Act: Potential impacts on energy

    International Nuclear Information System (INIS)

    This report provides an overview of the provisions of the Clean Air Act and its Amendments of 1990 that identify hazardous air pollutant (HAP) emissions and addresses their regulation by the US Environmental Protection Agency (EPA). It defines the major energy sector sources of these HAPs that would be affected by the regulations. Attention is focused on regulations that would cover coke oven emissions; chromium emission from industrial cooling towers and the electroplating process; HAP emissions from tank vessels, asbestos-related activities, organic solvent use, and ethylene oxide sterilization; and emissions of air toxics from municipal waste combustors. The possible implications of Title III regulations for the coal, natural gas, petroleum, uranium, and electric utility industries are examined. The report discusses five major databases of HAP emissions: (1) TRI (EPA's Toxic Release Inventory); (2) PISCES (Power Plant Integrated Systems: Chemical Emissions Studies developed by the Electric Power Research Institute); (3) 1985 Emissions Inventory on volatile organic compounds (used for the National Acid Precipitation Assessment Program); (4) Particulate Matter Species Manual (EPA); and (5) Toxics Emission Inventory (National Aeronautics and Space Administration). It also offers information on emission control technologies for municipal waste combustors

  7. 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…

  8. Encoding information into precipitation structures

    Science.gov (United States)

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

    2008-12-01

    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.

  9. Worker Knowledge of Pension Provisions

    OpenAIRE

    Mitchell, Olivia S.

    1987-01-01

    This paper evaluates the quality of workers' information regarding pension offerings using both administrative records and worker reports of pension provisions. Missing and misinformation proves to be widespread. Unionized employees, higher income workers and those in large firms, the better educated, and those with greater seniority are better informed about their pensions. There are also demographic differences: nonwhites have less pension knowledge than whites, but women are better informe...

  10. Evolutionary Dynamics Of Service Provisioning

    Directory of Open Access Journals (Sweden)

    Harry Katzan, Jr.

    2012-03-01

    Full Text Available Business evolves according to market conditions, based on availability and choice.  The purpose of this paper is to develop a model that describes how service provisioning evolves through a metaphor of selection, survival of the fittest, replication, and mutation.  Clients are free to choose a service provider within a provider category, and the model describes and delineates that behavior.  Equations and examples are given.

  11. Network Provisioning Using Multimedia Aggregates

    Directory of Open Access Journals (Sweden)

    Joan Vila-Carbó

    2008-01-01

    Full Text Available Multimedia traffic makes network provisioning a key issue. Optimal provisioning of network resources is crucial for reducing the service cost of multimedia transmission. Multimedia traffic requires not only provisioning bandwidth and buffer resources in the network but also guaranteeing a given maximum end-to-end delay. In this paper we present methods and tools for the optimal dimensioning of networks based on multimedia aggregates. The proposed method minimises the network resources reservations of traffic aggregates providing a bounded delay. The paper also introduces several methods to generate multimedia traffic aggregation using real video traces. The method is evaluated using a network topology based on the European GÉANT network. The results of these simulations allow us to discover the relationship between a required delay and the necessary bandwidth reservation (or the achievable utilisation limit. An interesting conclusion of these scenarios is that, following several recommendations, the network utilisation can reach values of around 80% or higher.

  12. The Provision of Paralegal Education in Scotland

    OpenAIRE

    McIlwhan, Rosemarie; Miller, Alison

    2013-01-01

    This research follows on from research on the Provision of Legal Education in Scotland conducted for the Open University in 2010 and on research mapping the PDA curriculum with the Skills for Justice functional map in 2012. The focus of this research is to map the provision of paralegal education in Scotland and identify gaps in that provision.

  13. 40 CFR 52.2183 - Variance provision.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Variance provision. 52.2183 Section 52...) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) South Dakota § 52.2183 Variance provision. The revisions to the variance provisions in Chapter 74:26:01:31.01 of the South Dakota Air...

  14. 47 CFR 32.6512 - Provisioning expense.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Provisioning expense. 32.6512 Section 32.6512... FOR TELECOMMUNICATIONS COMPANIES Instructions for Expense Accounts § 32.6512 Provisioning expense. (a) This account shall include costs incurred in provisioning material and supplies, including...

  15. 24 CFR 5.321 - Lease provisions.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Lease provisions. 5.321 Section 5... General Requirements § 5.321 Lease provisions. (a) Lease provisions. (1) PHAs which have established pet rules and project owners shall ensure that the leases for all tenants of projects for the elderly...

  16. Extraction of protein from high-temperature peanut meal using combination process with steam flash-explosion,alkaline-extraction and acid-precipitation%蒸汽闪爆结合碱溶酸沉法提取高温花生粕中的蛋白质

    Institute of Scientific and Technical Information of China (English)

    章玉清; 杨瑞金; 张文斌; 华霄; 赵伟

    2013-01-01

    以高温花生粕为研究对象,研究了蒸汽闪爆结合碱溶酸沉法提取花生蛋白质的工艺及其产品的功能性质.通过单因素实验和正交实验确定优化的工艺条件为:高温花生粕首先用0.3%的稀硫酸在60℃条件下搅拌浸泡2h;用清水洗去表面稀酸后沥干再进行蒸汽闪爆处理,条件为:爆破压力1.6MPa、维压时间5min;最后采用碱溶酸沉法提取蛋白质,条件为:温度60℃、pH9.5、料水比1∶12(g/mL)、浸提时间为2h.在此工艺条件下,高温花生粕中蛋白质的提取率达到52.6%,比传统碱溶酸沉工艺提高了10.8%,且所得蛋白质产品的持水性、乳化性、起泡性和起泡稳定性有了显著提高,分别增强了67.1%、141.0%、131.3%和107.4%.蒸汽闪爆技术结合碱溶酸沉法适用于从高温花生粕中提取蛋白质,不仅可以提高蛋白质的提取率,而且能够改善产品的功能性质.%A combined process with steam flash-explosion,alkaline-extraction and acid-precipitation was used to extract protein from high-temperature peanut meal.Through single factor and orthogonal test,the optimum conditions were figured out.Firstly,the high-temperature peanut meal was soaked in 0.3% sulfuric acid solution at 60℃ for 2h,then drained it and washed with water to remove the acid solution remained in the surface of the meal.The pretreated meal was treated with steam flash-explosion at 1.6MPa for 5min.The protein in the steam flash-exploded meal was extracted by alkaline-extraction and acid-precipitation process.The optimal condition for alkaline-extraction was solid to water ratio:1∶12(g/mL),pH9.5,60℃ and 2h.Under these conditions,the protein extraction rate reached 52.6%,which was 10.8% higher than conventional alkaline extraction and acid-precipitation process.The water holding capacity,emulsifying activity index,foaming capacity and foaming stability of the protein extracted using this combined process were significantly

  17. Co-precipitation of dissolved organic matter by calcium carbonate in Pyramid Lake, Nevada

    Science.gov (United States)

    Leenheer, Jerry A.; Reddy, Michael M.

    2008-01-01

    Our previous research has demonstrated that dissolved organic matter (DOM) influences calcium carbonate mineral formation in surface and ground water. To better understand DOM mediation of carbonate precipitation and DOM co-precipitation and/or incorporation with carbonate minerals, we characterized the content and speciation of DOM in carbonate minerals and in the lake water of Pyramid Lake, Nevada, USA. A 400-gram block of precipitated calcium carbonate from the Pyramid Lake shore was dissolved in 8 liters of 10% acetic acid. Particulate matter not dissolved by acetic acid was removed by centrifugation. DOM from the carbonate rock was fractionated into nine portions using evaporation, dialysis, resin adsorption, and selective precipitations to remove acetic acid and inorganic constituents. The calcium carbonate rock contained 0.23% DOM by weight. This DOM was enriched in polycarboxylic proteinaceous acids and hydroxy-acids in comparison with the present lake water. DOM in lake water was composed of aliphatic, alicyclic polycarboxylic acids. These compound classes were found in previous studies to inhibit calcium carbonate precipitation. DOM fractions from the carbonate rock were 14C-age dated at about 3,100 to 3,500 years before present. The mechanism of DOM co-precipitation and/or physical incorporation in the calcium carbonate is believed to be due to formation of insoluble calcium complexes with polycarboxylic proteinaceous acids and hydroxy-acids that have moderately large stability constants at the alkaline pH of the lake. DOM co-precipitation with calcium carbonate and incorporation in precipitated carbonate minerals removes proteinaceous DOM, but nearly equivalent concentrations of neutral and acidic forms of organic nitrogen in DOM remain in solution. Calcium carbonate precipitation during lime softening pretreatment of drinking water may have practical applications for removal of proteinaceous disinfection by-product precursors.

  18. Acid Rain. LC Science Tracer Bullet.

    Science.gov (United States)

    Hollmann, Pauline, Comp.

    The term "acid rain," also called "acid precipitation," generally refers to any precipitation having a pH value of less than 5.6. This guide to the literature on acid rain in the collections of the Library of Congress is not necessarily intended to be a comprehensive bibliography. It is designed to provide the reader with a set of resources that…

  19. PROVISIONS ACCOUNTANCY FOR PENSIONS AND SIMILAR LIABILITIES

    Directory of Open Access Journals (Sweden)

    MIHAELA COSMINA PETRE

    2012-05-01

    Full Text Available The foundation of accountancy provisions is based on IAS 37 „Provisions, Contingent Liabilities and Contingent Assets” and on „European Accountancy Regulations” aproved by OMFP no.3055/2009. The main problems regarding the provisions normalization and reglementation by using the mentioned sources of accountancy law refer to: provisions definition and delimitation, their acknowledgement, evaluation, modification and accounting.Pension provisions refer to the amount to be paid by the entity after the employees retirement. The provisions value is established by the specialists in the field. For determining their value there must be taken into account the age, length of service and staff rotation within the entity. Pension provisions are acknowledged on the length of service remained up to the pension time, when they are certain to be paid for a predictable period of time.

  20. Formate oxidation driven calcium carbonate precipitation by Methylocystis parvus OBBP

    NARCIS (Netherlands)

    Ganendra, G; De Muynck, W; Ho, A.; Arvaniti, EC; Hosseinkhani, B; Ramos, JA; Rahier, H; Boon, N.

    2014-01-01

    Microbially Induced Carbonate Precipitation (MICP) applied in the construction industry poses several disadvantages such as ammonia release to the air and nitric acid production. An alternative MICP from calcium formate by Methylocystis parvus OBBP is presented in this study to overcome these disadv

  1. Atrial Ectopics Precipitating Atrial Fibrillation

    OpenAIRE

    Johnson Francis

    2015-01-01

    Holter monitor tracing showing blocked atrial ectopics and atrial ectopic precipitating atrial fibrillation is being demonstrated. Initially it was coarse atrial fibrillation, which rapidly degenerated into fine atrial fibrillation.

  2. 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.

  3. Heavy Precipitation Events in Lithuania

    Science.gov (United States)

    Bukantis, A.; Rimkus, E.; Kažys, J.

    2010-09-01

    Analysis of heavy precipitation events in Lithuania is presented in this work. Research was divided into two parts. Spatial distribution and dynamic of heavy precipitation events in Lithuania during observation period (1961-2008) is presented in the first part and climate predictions for XXI century according to outputs of CCLM model are in the second. Daily data from 17 meteorological stations were used for the analysis of heavy precipitation events in Lithuania. Research covers period from 1961 to 2008. Annual and seasonal heavy precipitation values and the recurrence of extreme daily and 3-day precipitation events were analyzed. Spatial distribution of heavy precipitation events in Lithuania was determined; the trends of such precipitation recurrence were identified. Also, daily and 3-day annual maxima probabilities were calculated using the Generalized Extreme Value (GEV) distribution. 10, 30 and 100 years return period was analyzed. Finally, atmospheric circulation processes during heavy precipitation events were described using the adapted Hess & Brezowski macrocirculation form classification Predictions of changes of heavy precipitation recurrence in Lithuania are also presented in this study. Output data of the regional climate model CCLM (COSMO - Climate Limited-area Model) for the period 1971-2100 were used. Predictions were based on A1B and B1 emission scenarios. Despite of relatively small area and quite negligible differences in altitude there are significant unevenness in spatial distribution of heavy precipitation events in Lithuania. The mean annual number of cases when daily precipitation amount exceeded 10 mm fluctuates from 12.4 to 21.9 and from 5.3 to 10.5 when 3-day precipitation exceeded 20 mm. The probability of maximum precipitation amount for 10 year return period appears very familiar to spatial distribution of heavy precipitation recurrence: the highest values can be expected in the western part (55-60 mm daily and 75-85 mm in 3-days

  4. 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)

  5. Acid Rain: What It Is -- How You Can Help!

    Science.gov (United States)

    National Wildlife Federation, Washington, DC.

    This publication discusses the nature and consequences of acid precipitation (commonly called acid rain). Topic areas include: (1) the chemical nature of acid rain; (2) sources of acid rain; (3) geographic areas where acid rain is a problem; (4) effects of acid rain on lakes; (5) effect of acid rain on vegetation; (6) possible effects of acid rain…

  6. The precipitation and effect of nano nitrides in HSLC steel

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The existing forms of N and Al in HSLC (high strength low carbon) steel produced by TSCR (thin slab casting and rolling process), the precipitation thermodynamics and kinetics of AlN, and its effects on structure and mechanical property are studied. The experimental results show that only a small quantity of nitrogen is com- bined into AlN in HSLC steel produced by TSCR and most of the nitrogen in steel is still free nitrogen. Aluminum-nitride is mainly precipitated during the period of slow air cooling after coiling, but not during rolling and water cooling. The acid-soluble aluminum has no obvious effect on the grain size and mechanical property of HSLC steel produced by TSCR whose acid-soluble aluminum content is 0.005%―0.043%. The precipitation of AlN is not the main cause of grain refinement of HSLC steel produced by TSCR, nor is AlN the dominating precipitate that has precipitation strengthening effect. The nano nitrides are not pure AlN, but have complex compositions.

  7. The precipitation and effect of nano nitrides in HSLC steel

    Institute of Scientific and Technical Information of China (English)

    FU Jiei; LIU YangChun; WU HuaJie

    2008-01-01

    The existing forms of N and AI in HSLC (high strength low carbon) steel produced by TSCR (thin slab casting and rolling process),the precipitation thermodynamics and kinetics of AIN,and its effects on structure and mechanical property are stud-ied.The experimental results show that only a small quantity of nitrogen is com-bined into AIN in HSLC steel produced by TSCR and most of the nitrogen in steel is still free nitrogen.AIuminum-nitride is mainly precipitated during the period of slow air cooling after coiling,but not during rolling and water cooling.The acid-soluble aluminum has no obvious effect on the grain size and mechanical property of HSLC steel produced by TSCR whose acid-soluble aluminum content is 0.005%-0.043%.The precipitation of AIN is not the main cause of grain refinement of HSLC steel produced by TSCR,nor is AIN the dominating precipitate that has precipitation strengthening effect.The nano nitrides are not pure AIN,but have complex compositions.

  8. Metal particle's precipitation behavior in direct reading ferrography precipitator tube

    Institute of Scientific and Technical Information of China (English)

    尹凤福; 李谋渭

    2004-01-01

    A new metal particle monitoring instrument was developed by improving the traditional direct reading ferrography. The precipitation behaviors of sub-magnetic particles, magnetic particles, and the mixture of these particles were examined with the instrument. The results show that the precipitation behavior of sub-magnetic metal particles of copper and aluminum is not random as it was believed previously. The sub-magnetic particles show a distribution in the precipitator tube, almost the same as the deposition curves as the magnetic particles have. The deposition amount of particles is increased in the oil which consists of several different kinds of particles. On the base of these experiments, a new index used for the total quantity of wear was redefined.

  9. Are hourly precipitation extremes increasing faster than daily precipitation extremes?

    Science.gov (United States)

    Barbero, Renaud; Fowler, Hayley; Blenkinsop, Stephen; Lenderink, Geert

    2016-04-01

    Extreme precipitation events appear to be increasing with climate change in many regions of the world, including the United States. These extreme events have large societal impacts, as seen during the recent Texas-Oklahoma flooding in May 2015 which caused several billion in damages and left 47 deaths in its path. Better understanding of past changes in the characteristics of extreme rainfall events is thus critical for reliable projections of future changes. Although it has been documented in several studies that daily precipitation extremes are increasing across parts of the contiguous United States, very few studies have looked at hourly extremes. However, this is of primary importance as recent studies on the temperature scaling of extreme precipitation have shown that increases above the Clausius-Clapeyron (~ 7% °C-1) are possible for hourly precipitation. In this study, we used hourly precipitation data (HPD) from the National Climatic Data Center and extracted more than 1,000 stations across the US with more than 40 years of data spanning the period 1950-2010. As hourly measurements are often associated with a range of issues, the data underwent multiple quality control processes to exclude erroneous data. While no significant changes were found in annual maximum precipitation using both hourly and daily resolution datasets, significant increasing trends in terms of frequency of episodes exceeding present-day 95th percentiles of wet hourly/daily precipitation were observed across a significant portion of the US. The fraction of stations with significant increasing trends falls outside the confidence interval range during all seasons but the summer. While less than 12% of stations exhibit significant trends at the daily scale in the wintertime, more than 45% of stations, mostly clustered in central and Northern United States, show significant increasing trends at the hourly scale. This suggests that short-duration storms have increased faster than daily

  10. The Global Precipitation Measurement Mission

    Science.gov (United States)

    Jackson, Gail

    2014-05-01

    The Global Precipitation Measurement (GPM) mission's Core satellite, scheduled for launch at the end of February 2014, is well designed estimate precipitation from 0.2 to 110 mm/hr and to detect falling snow. Knowing where and how much rain and snow falls globally is vital to understanding how weather and climate impact both our environment and Earth's water and energy cycles, including effects on agriculture, fresh water availability, and responses to natural disasters. The design of the GPM Core Observatory is an advancement of the Tropical Rainfall Measuring Mission (TRMM)'s highly successful rain-sensing package [3]. The cornerstone of the GPM mission is the deployment of a Core Observatory in a unique 65o non-Sun-synchronous orbit to serve as a physics observatory and a calibration reference to improve precipitation measurements by a constellation of 8 or more dedicated and operational, U.S. and international passive microwave sensors. The Core Observatory will carry a Ku/Ka-band Dual-frequency Precipitation Radar (DPR) and a multi-channel (10-183 GHz) GPM Microwave Radiometer (GMI). The DPR will provide measurements of 3-D precipitation structures and microphysical properties, which are key to achieving a better understanding of precipitation processes and improving retrieval algorithms for passive microwave radiometers. The combined use of DPR and GMI measurements will place greater constraints on possible solutions to radiometer retrievals to improve the accuracy and consistency of precipitation retrievals from all constellation radiometers. Furthermore, since light rain and falling snow account for a significant fraction of precipitation occurrence in middle and high latitudes, the GPM instruments extend the capabilities of the TRMM sensors to detect falling snow, measure light rain, and provide, for the first time, quantitative estimates of microphysical properties of precipitation particles. The GPM Core Observatory was developed and tested at NASA

  11. Timber Mountain Precipitation Monitoring Station

    International Nuclear Information System (INIS)

    A precipitation monitoring station was placed on the west flank of Timber Mountain during the year 2010. It is located in an isolated highland area near the western border of the Nevada National Security Site (NNSS), south of Pahute Mesa. The cost of the equipment, permitting, and installation was provided by the Environmental Monitoring Systems Initiative (EMSI) project. Data collection, analysis, and maintenance of the station during fiscal year 2011 was funded by the U.S. Department of Energy, National Nuclear Security Administration, Nevada Site Office Environmental Restoration, Soils Activity. The station is located near the western headwaters of Forty Mile Wash on the Nevada Test and Training Range (NTTR). Overland flows from precipitation events that occur in the Timber Mountain high elevation area cross several of the contaminated Soils project CAU (Corrective Action Unit) sites located in the Forty Mile Wash watershed. Rain-on-snow events in the early winter and spring around Timber Mountain have contributed to several significant flow events in Forty Mile Wash. The data from the new precipitation gauge at Timber Mountain will provide important information for determining runoff response to precipitation events in this area of the NNSS. Timber Mountain is also a groundwater recharge area, and estimation of recharge from precipitation was important for the EMSI project in determining groundwater flowpaths and designing effective groundwater monitoring for Yucca Mountain. Recharge estimation additionally provides benefit to the Underground Test Area Sub-project analysis of groundwater flow direction and velocity from nuclear test areas on Pahute Mesa. Additionally, this site provides data that has been used during wild fire events and provided a singular monitoring location of the extreme precipitation events during December 2010 (see data section for more details). This letter report provides a summary of the site location, equipment, and data collected in

  12. Recovery of small DNA fragments from serum using compaction precipitation.

    Directory of Open Access Journals (Sweden)

    Binh V Vu

    Full Text Available BACKGROUND: While most nucleic acids are intracellular, trace amounts of deoxyribonucleic acid (DNA and ribonucleic acid (RNA, including micro RNAs, can also be found in peripheral blood. Many studies have suggested the potential utility of these circulating nucleic acids in prenatal diagnosis, early cancer detection, and the diagnosis of infectious diseases. However, DNA circulating in blood is usually present at very low concentrations (ng/ml, and is in the form of relatively small fragments (<1,000 bp, making its isolation challenging. METHODS: Here we report an improved method for the isolation of small DNA fragments from serum using selective precipitation by quaternary ammonium compaction agents. A 151 bp fragment of double-stranded DNA from the Escherichia coli bacteriophage lambda served as the model DNA in our experiments. DNA was serially diluted in serum until undetectable by conventional polymerase chain reaction (PCR, before being enriched by compaction precipitation. RESULTS: Starting with concentrations two to three orders of magnitude lower than the PCR-detectable level (0.01 ng/ml, we were able to enrich the DNA to a detectable level using a novel compaction precipitation protocol. The isolated DNA product after compaction precipitation was largely free of serum contaminants and was suitable for downstream applications. CONCLUSIONS: Using compaction precipitation, we were able to isolate and concentrate small DNA from serum, and increase the sensitivity of detection by more than four orders of magnitude. We were able to recover and detect very low levels (0.01 ng/ml of a small DNA fragment in serum. In addition to being very sensitive, the method is fast, simple, inexpensive, and avoids the use of toxic chemicals.

  13. The characterisation of precipitated magnetites

    International Nuclear Information System (INIS)

    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. Determination of silicon dioxide in siliceous refractory materials by potassium fluosilicate precipitation-acid base titration method%氟硅酸钾沉淀-酸碱滴定法测定硅质耐火材科料中二氧化硅

    Institute of Scientific and Technical Information of China (English)

    李环亭; 董艳艳; 刘晓毅; 孙晓红; 赵维平

    2011-01-01

    提出一种不用铂金坩埚和不需要用氢氟酸挥硅的氟硅酸钾沉淀-酸碱滴定法测定硅质耐火材料中SiO2含量方法,考察了检测的准确度和精确度,探讨了影响检测的干扰因素和可能的干扰机理.试样在银或者镍坩埚中,用氢氧化钠熔融,二氧化硅转化为硅酸钠,在有过量氯化钾存在的强酸性溶液中加入氟化钾溶液,生成氟硅酸钾沉淀,经过滤、洗涤后溶于沸水中,以酚酞为指示剂,NaOH标准溶液滴定水解后生成的氢氟酸.试样中SiO2的质量分数与Al2O3的质量分数比值大于或等于3.5时Al2O3对测定没有影响.应用本法检测硅质砂岩、硅砖等硅质耐火材料样品中的SiO2含量,测定值与认定值相符,且重复性较好.%A determination method of silicon dioxide in siliceous refractory materials by potassium fluosilicate precipitation-acid-base titration method was established. Neither a platinum crucible nor the volatilization of silicon by hydrofluoric acid was needed. The determination accuracy and precision were investigated. The interference factors and possible interference mechanism were discussed. The samples were melted in a silver or nickel crucible with sodium hydroxide, during which the silicon dioxide in sample was converted into sodium silicate. Then, potassium fluoride solution was added into strong acid solution containing excessive potassium chloride to form potassium fluosilicate precipitation. After filtration and washing, the precipitates were dissolved in boiling water. The generated hydrofluoric acid through hydrolysis was titrated with standard sodium hydroxide solution using phenolphthalein as indicator. It was generally considered that. when the ratio between mass fraction of silicon dioxide and aluminum oxide in sample was higher or equal to 3. 5, the aluminum oxide had no influence on the determination. This method has been applied to the determination of silicon dioxide in siliceous refractory materials

  15. Precipitation kinetics of a continuous precipitator, with application to the precipitation of ammonium polyuranate

    International Nuclear Information System (INIS)

    A mathematical model describing the kinetics of continuous precipitation was developed which accounts for crystal nucleation, crystal growth, primary coagulation, and secondary coagulation. Population density distributions, average particle sizes, dominant particle sizes, and suspension density fractions of the crystallites, primary agglomerates, and secondary agglomerates leaving the continuous precipitator can be determined. This kinetic model was applied to the continuous precipitation of ammonium polyuranate, which consists of: (1) elementary crystals, (2) clusters or primary coagulated particles, and (3) agglomerates or secondary coagulated particles. The crystallites are thin, submicron, hexagonal platelets. The clusters had an upper size limit of about 7 μ in diameter and contained numerous small voids (less than 0.3 μm) due to the packing of the crystallites. The agglomerates had an upper size limit of about 40 μm in diameter and contained large voids (approximately 1 μm). The particle size distribution and particle structure of the ammonium polyuranate precipitate can be controlled through proper regulation of the precipitation conditions. The ratio of clusters to agglomerates can be best controlled through the uranium concentration, and the cohesiveness or internal bonding strength of the particles can be controlled with the ammonium to uranium reacting feed mole ratio. These two conditions, in conjunction with the residence time, will determine the nucleation rates, growth rates, and size distributions of the particles leaving the continuous precipitator. With proper control of these physical particle characteristics, the use of pore formers, ball-milling, and powder blending can probably be eliminated from the nuclear fuel fabrication process, substantially reducing the cost

  16. How often precipitation records break?

    Science.gov (United States)

    Papalexiou, Simon Michael; Oikonomou, Maria; Floutsakou, Athina; Bessas, Nikolaos; Mamassis, Nikos

    2016-04-01

    How often precipitation records break? Are there any factors that determine the average time needed for the next maximum to occur? In order to investigate these simple questions we use several hundreds of daily precipitation records (more than 100 years long each) and we study the time intervals between each successive maximum precipitation value. We investigate if the record breaking time interval is related (a) to the autocorrelation structure, (b) to probability dry, and (c) to the tail of the marginal distribution. For the last, we first, evaluate which type of tail is better fitted by choosing among three general types of tails corresponding to the distributions Pareto, Lognormal and Weibull; and second, we assess the heaviness of the tail based on the estimated shape parameter. The performance of each tail is evaluated in terms of return period values, i.e., we compare the empirical return periods of precipitation values above a threshold with the predicted ones by each of the three types of fitted tails.

  17. Electrostatic Precipitator (ESP) TRAINING MANUAL

    Science.gov (United States)

    The manual assists engineers in using a computer program, the ESPVI 4.0W, that models all elements of an electrostatic precipitator (ESP). The program is a product of the Electric Power Research Institute and runs in the Windows environment. Once an ESP is accurately modeled, the...

  18. Impact of clouds and precipitation on atmospheric aerosol

    Science.gov (United States)

    Andronache, Constantin

    2015-04-01

    Aerosols have a significant impact on the dynamics and microphysics of continental mixed-phase convective clouds. High aerosol concentrations provide enhanced cloud condensation nuclei that can lead to the invigoration of convection and increase of surface rainfall. Such effects are dependent on environmental conditions and aerosol properties. Clouds are not only affected by aerosol, they also alter aerosol properties by various processes. Cloud processing of aerosol includes: convective redistribution, modification in the number and size of aerosol particles, chemical processing, new particle formation around clouds, and aerosol removal by rainfall to the surface. Among these processes, the wet removal during intense rain events, in polluted continental regions, can lead to spikes in acidic deposition into environment. In this study, we address the effects of clouds and precipitation on the aerosol distribution in cases of convective precipitation events in eastern US. We examine the effects of clouds and precipitation on various aerosol species, as well as their temporal and spatial variability.

  19. Synchrotron X-ray induced solution precipitation of nanoparticles

    CERN Document Server

    Lee, H J; Hwu, Y; Tsai, W L

    2003-01-01

    By irradiating a solution in electroless Ni deposition using synchrotron X-rays, Ni composite was found to nucleate homogeneously and eventually precipitate in the form of nanoparticles. The size of the nanoparticles precipitated is rather uniform (100-300 nm depending on the applied temperature). By the addition of an organic acid, well-dispersed nanoparticles could be effectively deposited on glass substrate. The hydrated electrons (e sub a sub q sup -), products of radiolysis of water molecules by synchrotron X-rays, may be responsible for the effective reduction of the metal ions, resulting in homogeneous nucleation and nanoparticle formation. Our results suggest that synchrotron X-ray can be used to induce solution precipitation of nanoparticles and therefore lead to a new method of producing nanostructured particles and coating.

  20. Conditional Generation of Monthly Precipitation

    Science.gov (United States)

    Kim, U.; Kaluarachchi, J. J.

    2006-12-01

    Monthly precipitation models can be used in basin-wide modeling to develop long-term strategies for water resources planning and management and to estimate the change of water yield due to climate change. Such precipitation models are especially important for effective management of river basins in developing countries such as the upper Blue Nile River basin of Ethiopia where the water resource utilization is limited. Many studies have been previously performed to preserve historical temporal and spatial structures when generating precipitation series. The main focus of those studies was to preserve the historical statistics. Other important factors to be considered are transition and spatial correlations. A few recent studies attempted to preserve transition as well as the statistics of historical record. These studies provided satisfactory results while showing the difficulty and complexity of computations in their methods. The conditional generation method (CGM) that can preserve both historical temporal and spatial structures is presented in this study. Because the CGM is driven from the historical conditional probabilities occurring given amounts of precipitation between two successive months or two stations, it is computationally simple and reliable, i.e., parameterization, inverse matrix, or optimum band width is not required. The CGM was applied to reproducing the precipitation pattern of the upper Blue Nile River basin in Ethiopia using monthly precipitation data of 10 stations to demonstrate its applicability. Comparing to the method of inverse transformation of cumulative distribution functions of the gamma distribution and nonparametric kernel estimator with variable band width selected from the goodness-of-fit tests, the CGM showed improved performance, especially in representing the transition characteristics. The CGM also generated the historical spatial correlations between the stations with acceptable accuracy. The results suggested that the CGM

  1. 40 CFR 165.80 - General provisions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false General provisions. 165.80 Section 165.80 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE MANAGEMENT AND DISPOSAL Standards for Pesticide Containment Structures § 165.80 General provisions. (a)...

  2. 40 CFR 165.40 - General provisions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false General provisions. 165.40 Section 165.40 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE MANAGEMENT AND DISPOSAL Refillable Container Standards: Container Design § 165.40 General provisions....

  3. 12 CFR 931.9 - Transition provision.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 7 2010-01-01 2010-01-01 false Transition provision. 931.9 Section 931.9 Banks and Banking FEDERAL HOUSING FINANCE BOARD FEDERAL HOME LOAN BANK RISK MANAGEMENT AND CAPITAL STANDARDS FEDERAL HOME LOAN BANK CAPITAL STOCK § 931.9 Transition provision. (a) In general. Each Bank shall...

  4. 12 CFR 1261.2 - General provisions.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 7 2010-01-01 2010-01-01 false General provisions. 1261.2 Section 1261.2 Banks and Banking FEDERAL HOUSING FINANCE AGENCY FEDERAL HOME LOAN BANKS FEDERAL HOME LOAN BANK DIRECTORS Federal Home Loan Bank Boards of Directors: Eligibility and Elections § 1261.2 General provisions....

  5. 50 CFR 71.12 - General provisions.

    Science.gov (United States)

    2010-10-01

    ...) MANAGEMENT OF FISHERIES CONSERVATION AREAS HUNTING AND FISHING ON NATIONAL FISH HATCHERY AREAS Fishing § 71.12 General provisions. The following provisions shall apply to public sport fishing on a national... may be amended as needed to meet management responsibilities for the area....

  6. 28 CFR 512.21 - Copyright provisions.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Copyright provisions. 512.21 Section 512... ADMINISTRATION RESEARCH Research § 512.21 Copyright provisions. (a) An employee of the Bureau may not copyright... non-employee may copyright original materials developed as a result of research conducted under...

  7. 48 CFR 873.110 - Solicitation provisions.

    Science.gov (United States)

    2010-10-01

    ... RFQs and solicitations, substantially the same as the provision at 852.273-71, Alternative negotiation techniques, when either of the alternative negotiation techniques described in 873.111(e)(1) will be used... evaluation, in lieu of the provision at 52.212-2, Evaluation—Commercial Items, when the...

  8. 40 CFR 141.76 - Recycle provisions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Recycle provisions. 141.76 Section 141...) NATIONAL PRIMARY DRINKING WATER REGULATIONS Filtration and Disinfection § 141.76 Recycle provisions. (a... recycle spent filter backwash water, thickener supernatant, or liquids from dewatering processes must...

  9. 40 CFR 35.6595 - Contract provisions.

    Science.gov (United States)

    2010-07-01

    ... STATE AND LOCAL ASSISTANCE Cooperative Agreements and Superfund State Contracts for Superfund Response Actions Procurement Requirements Under A Cooperative Agreement § 35.6595 Contract provisions. (a) General... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Contract provisions. 35.6595 Section...

  10. 7 CFR 226.25 - Other provisions.

    Science.gov (United States)

    2010-01-01

    ... Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS CHILD AND ADULT CARE FOOD PROGRAM Other Provisions § 226.25 Other provisions... 7 CFR part 3016 or 7 CFR part 3019, as applicable. (b) State requirements. Nothing contained in...

  11. Acid rain information book. Second edition

    International Nuclear Information System (INIS)

    Potential consequences of widespread acid precipitation are reviewed through an extensive literature search. Major aspects of the acid rain phenomena are discussed, areas of uncertainty identified, and current research summarized

  12. Implementing the optimal provision of ecosystem services.

    Science.gov (United States)

    Polasky, Stephen; Lewis, David J; Plantinga, Andrew J; Nelson, Erik

    2014-04-29

    Many ecosystem services are public goods whose provision depends on the spatial pattern of land use. The pattern of land use is often determined by the decisions of multiple private landowners. Increasing the provision of ecosystem services, though beneficial for society as a whole, may be costly to private landowners. A regulator interested in providing incentives to landowners for increased provision of ecosystem services often lacks complete information on landowners' costs. The combination of spatially dependent benefits and asymmetric cost information means that the optimal provision of ecosystem services cannot be achieved using standard regulatory or payment for ecosystem services approaches. Here we show that an auction that sets payments between landowners and the regulator for the increased value of ecosystem services with conservation provides incentives for landowners to truthfully reveal cost information, and allows the regulator to implement the optimal provision of ecosystem services, even in the case with spatially dependent benefits and asymmetric information.

  13. Water-soluble primary amine compounds in rural continental precipitation

    Science.gov (United States)

    Gorzelska, Krystyna; Galloway, James N.; Watterson, Karen; Keene, William C.

    Procedures for collecting, storing and analysing precipitation samples for organic nitrogen studies were developed. These procedures preserve chemical integrities of the species of interest, allow for up to 3 months storage and quantitative determination of water-soluble primary amine compounds, with the overall error at the 2 nM detection limit of less than 30%. This methodology was applied to study amino compounds in precipitation samples collected over a period of one year in central Virginia. Nitrogen concentrations of 13 amino acids and 3 aliphatic amines were summed to calculate the total amine nitrogen (TAN). The concentration of TAN ranged from below our detection level to 6658 nM, and possibly reflected a seasonal variation in the source strength of the atmospheric amines. Overall, the most commonly occurring amino compounds were methyl amine, ethyl amine, glutamic acid, glycine and serine. On average, the highest overall contribution to the TAN came from arginine, asparagine, glutamine, methyl amine, serine and alanine. However, large qualitative and quantitative variations observed among samples warrant caution in interpretation and application of the averaged values. TAN in Charlottesville precipitation contributed from less than 1 to ca 10% of the ammonium nitrogen level. However, our estimates show that amino compounds may contribute significantly to reduced nitrogen budget in precipitation in remote regions.

  14. Extraction and Recovery of Lead from Kaldo Slag by Acetate Acid and Sodium Acetate Leaching and Sodium Sulfite Precipitation%用乙酸-乙酸钠浸出及亚硫酸钠沉淀分离回收卡尔多炉渣中的铅

    Institute of Scientific and Technical Information of China (English)

    吕建军; 肖连生; 张启修; 黄芍英; 胡磊; 曾之琪

    2013-01-01

    采用乙酸-乙酸钠溶液浸出卡尔多炉渣中的铅,用无水亚硫酸钠沉淀分离浸出液中的铅,沉铅滤液脱硫(加氢氧化钡)后返回浸出工序,研究了相关工艺参数对铝直收率及亚硫酸铅纯度的影响.结果表明:在搅拌速度为300 r/min,浸出温度为室温(25℃),乙酸、乙酸钠浓度分别为1 mol/L和2 mol/L,液固比5∶1,浸出时间2h时,铅的浸出率可达到99.1%,浸出液含铅78.3 g/L;在搅拌速度200 r/min,沉淀温度为室温(25℃),无水亚硫酸钠过量系数1.25,沉淀时间20 min时,沉铅滤液余铅含量可降至4×10-6,亚硫酸铅纯度达到97.4%,铅的直收率可达到98%以上;沉铅滤液除硫酸根后,补充乙酸、乙酸钠至摩尔浓度分别为1mol/L和2 mol/L,返回浸出工序,按浸出的最优条件处理同样的卡尔多炉渣,铅的浸出率可以达到98.1%,实现了浸出剂的闭路循环.%Lead was leached from Kaldo slag using acetate acid and sodium acetate, then precipitated and extracted from the leaching liquor by sodium sulfite. The lead-extracted filtrate was returned to the leaching process after being desulfurized by barium hydroxide. The effects of related process parameters on aluminum recovery and lead sulfite purity were investigated. The results show that under the conditions such as stirring speed of 300 r/min, leaching temperature of 251, acetate acid concertration of 1 mol/L, sodium acetate concertration of 2 mol/L, liquid-solid ratio of 5:1 and leaching time of 2 h, the leaching rate of lead can reach to 99.1%, with a lead content of 78.3 g/L in the leaching liquor. Under the following conditions; stirring speed of 200 r/min, precipitation temperature of 25 ℃, an excess coefficient of hydrous sodium sulfite of 1.25 and precipitation time of 20 min, the lead content in the lead-extracted filtrate can be decreased to 4 × 10-6 while the purity of lead sulfite and lead recovery reaches to 97.4% and 98% respectively. After desulfurization

  15. 7 CFR 457.160 - Processing tomato crop insurance provisions.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Processing tomato crop insurance provisions. 457.160... tomato crop insurance provisions. The Processing Tomato Crop Insurance Provisions for the 2005 and... polices: Processing Tomato Crop Provisions If a conflict exists among the policy provisions, the order...

  16. Precipitation patterns during channel flow

    Science.gov (United States)

    Jamtveit, B.; Hawkins, C.; Benning, L. G.; Meier, D.; Hammer, O.; Angheluta, L.

    2013-12-01

    Mineral precipitation during channelized fluid flow is widespread in a wide variety of geological systems. It is also a common and costly phenomenon in many industrial processes that involve fluid flow in pipelines. It is often referred to as scale formation and encountered in a large number of industries, including paper production, chemical manufacturing, cement operations, food processing, as well as non-renewable (i.e. oil and gas) and renewable (i.e. geothermal) energy production. We have studied the incipient stages of growth of amorphous silica on steel plates emplaced into the central areas of the ca. 1 meter in diameter sized pipelines used at the hydrothermal power plant at Hellisheidi, Iceland (with a capacity of ca 300 MW electricity and 100 MW hot water). Silica precipitation takes place over a period of ca. 2 months at approximately 120°C and a flow rate around 1 m/s. The growth produces asymmetric ca. 1mm high dendritic structures ';leaning' towards the incoming fluid flow. A novel phase-field model combined with the lattice Boltzmann method is introduced to study how the growth morphologies vary under different hydrodynamic conditions, including non-laminar systems with turbulent mixing. The model accurately predicts the observed morphologies and is directly relevant for understanding the more general problem of precipitation influenced by turbulent mixing during flow in channels with rough walls and even for porous flow. Reference: Hawkins, C., Angheluta, L., Hammer, Ø., and Jamtveit, B., Precipitation dendrites in channel flow. Europhysics Letters, 102, 54001

  17. Predictibility in Nowcasting of Precipitation

    Science.gov (United States)

    Zawadzki, I.; Sourcel, M.; Berenguer, M.

    2009-05-01

    Present short term precipitation forecasting is based on two methods: Lagrangian persistence (nowcasting) and numerical weather prediction (NWP). An improvement over these methods is obtained by the combination of the two. The obvious shortcoming of nowcasting is its severe limitation in capturing new development or dissipation of precipitation. NWP has the ability to predict both but very imprecisely. An attempt to correct model errors by post-processing leads to some improvement in the skill of NWP, but the improvement, although significative, is not very impressive. The goal of our effort is to take a step back and to describe, in a quantitative manner, a) the nature of the uncertainties affecting Lagrangian persistence and NWP forecasts, as well as to determineb) the physical causes of the uncertainties. We quantify the uncertainties in short term forecasting due to limitation of nowcasting algorithms and NWP to capture correctly some of the physical phenomena that determine the predictability of precipitation. The first factor considered is the diurnal cycle that appears as the one physically determined factors that limit the precision of short term prediction. We study the cycle in radar mosaics over US and compare this to nowcasts and model outputs. The seasonal and geographical dependence of the diurnal cycle is quantitatively evaluated.

  18. MAP3S/RAINE precipitation chemistry network: quality control

    Energy Technology Data Exchange (ETDEWEB)

    1980-10-01

    The participants of the precipitation chemistry network of the Multi-State Atmospheric Power Production Pollution Study/Regional Acidity of Industrial Emissions (MAP3S/RAINE) have developed procedures for maintenance of high quality output from the network operation. The documented procedures-most of which were in place before the network began sampling in 1976-include those for site selection and verification, field equipment, laboratory and data handling, and external laboratory quality testing.

  19. U.S. 15 Minute Precipitation Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — U.S. 15 Minute Precipitation Data is digital data set DSI-3260, archived at the National Climatic Data Center (NCDC). This is precipitation data. The primary source...

  20. European climate change experiments on precipitation change

    DEFF Research Database (Denmark)

    Beier, Claus

    Presentation of European activities and networks related to experiments and databases within precipitation change......Presentation of European activities and networks related to experiments and databases within precipitation change...

  1. Whither Acid Rain?

    OpenAIRE

    Peter Brimblecombe

    2000-01-01

    Acid rain, the environmental cause célèbre of the 1980s seems to have vanished from popular conscience. By contrast, scientific research, despite funding difficulties, has continued to produce hundreds of research papers each year. Studies of acid rain taught much about precipitation chemistry, the behaviour of snow packs, long-range transport of pollutants and new issues in the biology of fish and forested ecosystems. There is now evidence of a shift away from research in precipitation and s...

  2. Whither Acid Rain?

    Directory of Open Access Journals (Sweden)

    Peter Brimblecombe

    2000-01-01

    Full Text Available Acid rain, the environmental cause célèbre of the 1980s seems to have vanished from popular conscience. By contrast, scientific research, despite funding difficulties, has continued to produce hundreds of research papers each year. Studies of acid rain taught much about precipitation chemistry, the behaviour of snow packs, long-range transport of pollutants and new issues in the biology of fish and forested ecosystems. There is now evidence of a shift away from research in precipitation and sulfur chemistry, but an impressive theoretical base remains as a legacy.

  3. Effective assimilation of global precipitation: simulation experiments

    OpenAIRE

    Lien, Guo-Yuan; Kalnay, Eugenia; Miyoshi, Takemasa

    2013-01-01

    Past attempts to assimilate precipitation by nudging or variational methods have succeeded in forcing the model precipitation to be close to the observed values. However, the model forecasts tend to lose their additional skill after a few forecast hours. In this study, a local ensemble transform Kalman filter (LETKF) is used to effectively assimilate precipitation by allowing ensemble members with better precipitation to receive higher weights in the analysis. In addition, two other changes i...

  4. 22 CFR 513.625 - Exception provision.

    Science.gov (United States)

    2010-04-01

    ... GOVERNMENTWIDE REQUIREMENTS FOR DRUG-FREE WORKPLACE (GRANTS) Drug-Free Workplace Requirements (Grants) § 513.625 Exception provision. The Board head may waive with respect to a particular grant, in writing, a...

  5. 44 CFR 17.625 - Exception provision.

    Science.gov (United States)

    2010-10-01

    ... HOMELAND SECURITY GENERAL GOVERNMENTWIDE REQUIREMENTS FOR DRUG-FREE WORKPLACE (GRANTS) § 17.625 Exception provision. The agency head may waive with respect to a particular grant, in writing, a suspension...

  6. Photoinduced tellurium precipitation in CdTe

    Science.gov (United States)

    Sugai, Shunji

    1991-06-01

    Tellurium precipitation in CdTe is found to be induced by photoirradiation with energy higher than the energy gap at 240 W/sq cm. It is suggested that this photoinduced precipitation is related with the strong electron-phonon interactions, possibly self-trapped excitons. This irreducible tellurium precipitation may cause a serious problem for the life of semiconductor devices.

  7. The Social Provisioning Process and Heterodox Economics

    OpenAIRE

    Jo, Tae-Hee

    2016-01-01

    The social provisioning process is how heterodox economists define economics in general. Instead of having a narrow definition of what constitutes economics, such as the mainstream has with its allocation of scarce resources among competing ends via the price mechanism, heterodox economists have opted for a much more expansive definition that permits different theoretical explanations for ways in which the provisioning process can take place in different types of economies in different histor...

  8. Implementing the optimal provision of ecosystem services

    OpenAIRE

    Polasky, Stephen; Lewis, David J.; Plantinga, Andrew J.; Nelson, Erik

    2014-01-01

    Many ecosystem services are public goods available to everyone without charge, but the provision of these services often depends on the actions of private landowners who may bear cost to provide services. How to design incentives when the provision of services depends on the landscape pattern of conservation and where landowners have private information about costs presents a difficult challenge. Here we apply results from auction theory to design a payments scheme that achieves optimal provi...

  9. Economic Loan Loss Provision and Expected Loss

    Directory of Open Access Journals (Sweden)

    Stefan Hlawatsch

    2010-10-01

    Full Text Available The intention of a loan loss provision is the anticipation of the loan's expected losses by adjusting the book value of the loan. Furthermore, this loan loss provision has to be compared to the expected loss according to Basel II and, in the case of a difference, liable equity has to be adjusted. This however assumes that the loan loss provision and the expected loss are based on a similar economic rationale, which is only valid conditionally in current loan loss provisioning methods according to IFRS. Therefore, differences between loan loss provisions and expected losses should only result from different approaches regarding the parameter estimation within each model and not due to different assumptions regarding the outcome of the model. The provisioning and accounting model developed in this paper overcomes the before-mentioned shortcomings and is consistent with an economic rationale of expected losses. Additionally, this model is based on a close-to-market valuation of the loan that is in favor of the basic idea of IFRS. Suggestions for changes in current accounting and capital requirement rules are provided.

  10. Struvite Precipitation and Biological Dissolutions.

    OpenAIRE

    Ezquerro, Ander

    2010-01-01

    Struvite is a salt that is formed out of  Mg2+,NH4+ and PO43- and it crystallizes in form of MgNH4PO4.6H2O. Struvite‟s (magnesium ammonium phosphate or MAP) precipitation has recently been regarded as an interesting technique to remove phosphate and ammonium from waste water. The high elimination rates and the possibility of recycling the struvite as a direct slow release fertilizer make this process feasible and appealing. However, the costs due to the raw chemicals needed are drawbacks that...

  11. Radiation Induced Precipitation in Iron

    International Nuclear Information System (INIS)

    Foils of iron have been neutron-irradiated in the Swedish re- search reactor R2 to integrated doses in the range 1017 - 1019 nvt (> 1 MeV) and examined by transmission electron microscopy. Features have been observed having diffraction contrast similar to that of the prismatic dislocation loops formed in f.c.c. metals by the collapse of point-defect clusters. The features have been shown to be due to precipitation of impurities at radiation damage centres in the iron matrix

  12. The Contribution of Extreme Precipitation to the Total Precipitation in China

    Institute of Scientific and Technical Information of China (English)

    SUN Jian-Qi

    2012-01-01

    Using daily precipitation data from weather stations in China, the variations in the contribution of extreme precipitation to the total precipitation are analyzed. It is found that extreme precipitation accounts for approximately one third of the total precipitation based on the overall mean for China. Over the past half century, extreme precipitation has played a dominant role in the year-to-year variability of the total precipitation. On the decadal time scale, the extreme precipitation makes different contributions to the wetting and drying regions of China. The wetting trends of particular regions are mainly attributed to increases in extreme precipitation; in contrast, the drying trends of other regions are mainly due to decreases in non-extreme precipitation.

  13. Estimating Tropical Cyclone Precipitation from Station Observations

    Institute of Scientific and Technical Information of China (English)

    REN Fumin; WANG Yongmei; WANG Xiaoling; LI Weijing

    2007-01-01

    In this paper, an objective technique for estimating the tropical cyclone (TC) precipitation from station observations is proposed. Based on a comparison between the Original Objective Method (OOM) and the Expert Subjective Method (ESM), the Objective Synoptic Analysis Technique (OSAT) for partitioning TC precipitation was developed by analyzing the western North Pacific (WNP) TC historical track and the daily precipitation datasets. Being an objective way of the ESM, OSAT overcomes the main problems in OOM,by changing two fixed parameters in OOM, the thresholds for the distance of the absolute TC precipitation (D0) and the TC size (D1), into variable parameters.Case verification for OSAT was also carried out by applying CMORPH (Climate Prediction Center MORPHing technique) daily precipitation measurements, which is NOAA's combined satellite precipitation measurement system. This indicates that OSAT is capable of distinguishing simultaneous TC precipitation rain-belts from those associated with different TCs or with middle-latitude weather systems.

  14. Heavy precipitation episodes and cosmic rays variation

    Directory of Open Access Journals (Sweden)

    A. Mavrakis

    2006-01-01

    Full Text Available In this paper an attempt is made to investigate the possible temporal correlation between heavy precipitation episodes and cosmic rays' activity, on various time scales. Cosmic rays measurements are sparse and cover less extended periods than those of precipitation. Precipitation is largely influenced by local climatic and even physiographic conditions, while cosmic rays' distribution is far more uniform over an area. Thus, in an effort to cover a larger range of climatic characteristics, each cosmic rays station was correlated with several nearby precipitation stations. Selected statistical methods were employed for the data processing. The analysis was preformed on annual, seasonal, monthly and daily basis whenever possible. Wet and dry regions and/or seasons seem to present a different response of precipitation to cosmic rays variations. Also Forbush decreases in most cases will not lead to heavy precipitation, yet this might be sensitive to precipitable water availability.

  15. Radiative feedbacks on global precipitation

    International Nuclear Information System (INIS)

    The radiative kernel technique is employed to quantify twenty-first century changes to the tropospheric energy budget in the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4) models in order to better understand changes in global-mean precipitation. The strongest feedbacks on the tropospheric radiative cooling are found to be associated with increases in temperature and water vapor, with the water vapor feedback offsetting a significant portion (∼39%) of the increase in radiative cooling due to higher temperatures. Cloud and surface sensible heat flux feedbacks, though not as large in magnitude as the temperature and water vapor feedbacks, are important contributors to the intermodel difference in the global precipitation response to warming, or hydrological sensitivity. The direct effects of radiative forcing agents on the tropospheric energy budget are also important. Rising CO2 levels reduce tropospheric radiative cooling and hence limit the increase in global rainfall. Additionally, in some of the models, further reductions in radiative cooling occur due to increases in absorbing aerosol, suggesting that differences in aerosol forcing can explain part of the difference in hydrological sensitivity between models.

  16. Hemispheric Assymeries in Auroral Precipitation

    Science.gov (United States)

    Mende, S. B.

    2014-12-01

    It is widely accepted that the space weather related electrodynamic forcing of the geospace environment acts through the high geomagnetic latitude regions. At high latitudes inter-hemispheric asymmetries are largely due to the differences in solar illumination, the direction of the solar wind and interplanetary magnetic field components and to a lesser extent, due to differences between the two hemispheric internal fields. So far most research regarding interhemispheric differences concentrated on learning about the basic magnetosphere-ionosphere coupling mechanisms. It has been well established that sunlit conditions affect the energy flux of auroral precipitation resulting from the reduction in the mean energy of the auroral electrons in the sunlit summer hemisphere. This can be explained by the partial shorting out of the particle accelerating fields by the sunlight induced conductivity. It has also been found that sunlit conditions reduce the particle fluxes and therefore the associated field aligned currents. Unless the precipitation-induced conductivities overwhelm the sunlit component of conductivity, this would imply that the magnetospheric current generator responds to the ionospheric load in a highly non-linear manner. Interhemispheric currents may also play an important role that has not been fully explored. Interhemispheric asymmetries in substorm morphology have been explored critically because conjugacy implies that substorms have a common source at equatorial latitudes. In some cases the lack of conjugacy of substorms could be explained by considering the magnitude and direction of the IMF.

  17. Microbially-Mediated Precipitation of Calcium Carbonate Nanoparticles.

    Science.gov (United States)

    Kang, Ser Ku; Roh, Yul

    2016-02-01

    The objective of this study was to investigate the biomineralization of carbonate minerals using microorganisms (Wu Do-1) enriched from rhodoliths. A 16S rRNA sequence analysis showed that Wu Do-1 mainly contained Proteus mirabilis. The pH decreased from 6.5 to 5.3 over the first 4 days of incubation due to microbial oxidation of organic acids, after which it increased to 7.8 over the remaining incubation period. XRD analysis showed that the precipitates were Mg-rich cal- cite (MgxCa(1-x)CO3), whereas no precipitates were formed without the addition of Wu Do-1 in D-1 medium. SEM-EDS analyses showed that the Mg-rich calcite had a rhombohedron shape and consisted of Ca, Si and Mg with an extracelluar polymeric substance (EPS). In addition, TEM-EDS analyses revealed they were hexagon in shape, 500-700 nm in size, and composed of Ca, Mg, C, and O. These results indicated that Wu Do-1 induced precipitation of Mg-rich calcite on the cell walls and EPS via the accumulation of Ca and/or Mg ions. Therefore, microbial precipitation of carbonate nanoparticles may play an important role in metal and carbon biogeochemistry, as well as in carbon sequestration in natural environments.

  18. Optimization of magnetite carrier precipitation process for transuranic waste reduction

    Energy Technology Data Exchange (ETDEWEB)

    Slater, S.A.; Chamberlain, D.B.; Aase, S.A.; Babcock, B.D.; Conner, C.; Sedlet, J.; Vandegrift, G.F. [Argonne National Lab., IL (United States). Chemical Technology Div.

    1995-12-31

    Transuranic (TRU) waste that is being generated at Argonne National Laboratory has a TRU activity ranging from 10{sup 2} to 10{sup 7} nCi/g with a wide variety of chemical compositions. Currently, the waste is stored in highly acidic solutions that must be neutralized for intermediate storage. A magnetite carrier precipitation process has been adapted to concentrate TRU isotopes in a noncorrosive solid phase. In this paper, the authors report the results of a series of laboratory tests done to optimize the process. The parameters they optimized included (1) magnetite concentration used to precipitate the TRUs from solution, (2) formation of magnetite (in situ or ex situ), (3) processing pH, and (4) temperature and mixing time of the carrier precipitation. They also studied the effects of anions, cations, and complexing agents in the waste solutions on the carrier precipitation and the effect of magnetite solids loading on the filtration equipment. An overview is given of the planned full-scale process, which will be operated in a glovebox.

  19. Methods of Services Provision in Slovak Towns

    Directory of Open Access Journals (Sweden)

    Emília Sičáková-Beblavá

    2009-07-01

    Full Text Available This article deals with the methods of services provision in Slovak towns.  It addresses decision-making concerning selected services provision, based on a transaction cost economic model. The article looks at five types of services from that point of view. These are core services, i.e., services that are provided in most Slovak towns, thereby allowing outcomes of decision-making to be compared, and services which can be outsourced according to transaction cost theory. Findings partially confirm the hypothesis: Slovak towns do outsource, though “insourcing” moderately prevails. However, a comparison of several research studies in the area indicates a trend towards higher outsourcing of such local services provision.  The findings show that public bodies do not always select the most suitable methods of services provision, as suggested by the transaction costs theory (the Brown-Potoski model. This indicates that it is not only economic models that influence decision-making concerning the organization of services provision in the Slovak towns.

  20. Wet milling versus co-precipitation in magnetite ferrofluid preparation

    Directory of Open Access Journals (Sweden)

    Almásy László

    2015-01-01

    Full Text Available Various uses of ferrofluids for technical applications continuously raise the interest in improvement and optimization of preparation methods. This paper deals with preparation of finely granulated magnetite particles coated with oleic acid in hydrocarbon suspensions following either chemical co-precipitation from iron salt precursors or wet milling of micron size magnetite powder with the goal to compare the benefits and disadvantages of each method. Microstructural measurements showed that both methods gave similar magnetite particle size of 10-15 nm. Higher saturation magnetization was achieved for the wet-milled magnetite suspension compared to relatively rapid co-precipitation synthesis. Different efficacies of ferrophase incorporation into kerosene could be related to the different mechanisms of oleic acid bonding to nanoparticle surface. The comparative data show that wet milling represents a practicable alternative to the traditional co-precipitation since despite of longer processing time, chemicals impact on environment can be avoided as well as the remnant water in the final product.

  1. 5 CFR 9901.106 - Relationship to other provisions.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Relationship to other provisions. 9901... NATIONAL SECURITY PERSONNEL SYSTEM (NSPS) General Provisions § 9901.106 Relationship to other provisions... Governmentwide regulations that reference provisions under chapters 43, 51, 53, and 55 (subchapter V only),...

  2. Land use change suppresses precipitation

    Directory of Open Access Journals (Sweden)

    W. Junkermann

    2009-05-01

    Full Text Available A feedback loop between regional scale deforestation and climate change was investigated in an experiment using novel, small size airborne platforms and instrument setups. Experiments were performed in a worldwide unique natural laboratory in Western Australia, characterized by two adjacent homogeneous observation areas with distinctly different land use characteristics. Conversion of several ten thousand square km of forests into agricultural land began more than a century ago. Changes in albedo and surface roughness and the water budget of soil and the planetary boundary layer evolved over decades. Besides different meteorology we found a significant up to now overseen source of aerosol over the agriculture. The enhanced number of cloud condensation nuclei is coupled through the hydrological groundwater cycle with deforestation. Modification of surface properties and aerosol number concentrations are key factors for the observed reduction of precipitation. The results document the importance of aerosol indirect effects on climate due to nanometer size biogenic aerosol and human impact on aerosol sources.

  3. Natural chlorine and fluorine in the atmosphere, water and precipitation

    Science.gov (United States)

    Friend, James P.

    1990-01-01

    The geochemical cycles of chlorine and fluorine are surveyed and summarized as framework for the understanding of the global natural abundances of these species in the atmosphere, water, and precipitation. In the cycles the fluxes into and out of the atmosphere can be balanced within the limits of our knowledge of the natural sources and sinks. Sea salt from the ocean surfaces represent the predominant portion of the source of chlorine. It is also an important source of atmospheric fluorine, but volcanoes are likely to be more important fluorine sources. Dry deposition of sea salt returns about 85 percent of the salt released there. Precipitation removes the remainder. Most of the sea salt materials are considered to be cyclic, moving through sea spray over the oceans and either directly back to the oceans or deposited dry and in precipitation on land, whence it runs off into rivers and streams and returns to the oceans. Most of the natural chlorine in the atmosphere is in the form of particulate chloride ion with lesser amounts as gaseous inorganic chloride and methyl chloride vapor. Fluorine is emitted from volcanoes primarily as HF. It is possible that HF may be released directly form the ocean surface but this has not been confirmed by observation. HCl and most likely HF gases are released into the atmosphere by sea salt aerosols. The mechanism for the release is likely to be the provision of protons from the so-called excess sulfate and HNO3. Sea salt aerosol contains fluorine as F(-), MgF(+), CaF(+), and NaF. The concentrations of the various species of chlorine and fluorine that characterize primarily natural, unpolluted atmospheres are summarized in tables and are discussed in relation to their fluxes through the geochemical cycle.

  4. Marcasite precipitation from hydrothermal solutions

    Science.gov (United States)

    Murowchick, James B.; Barnes, H. L.

    1986-12-01

    Pyrite and marcasite were precipitated by both slow addition of aqueous Fe2+ and SiO32- to an H2S solution and by mixing aqueous Fe2+ and Na2S4 solutions at 75°C. H2S2 or HS2- and H2S4 or HS4- were formed in the S2O32- and Na2S4 experiments, respectively. Marcasite formed at pH dependent precipitation of pyrite and marcasite may be caused by electrostatic interactions between polysulfide species and pyrite or marcasite growth surfaces: the protonated ends of H2S2 and HS2 are repelled from pyrite growth sites but not from marcasite growth sites. The negative ions HS2 and S22- are strongly attracted to the positive pyrite growth sites. Masking of 1πg* electrons in the S2 group by the protons makes HS2 and H2S2 isoelectronic with AsS2- and As22-, respectively (TOSSELLet al., 1981). Thus, the loellingitederivative structure (marcasite) results when both ends of the polysulfide are protonated. Marcasite occurs abundantly only for conditions below pH 5 and where H2S2 was formed near the site of deposition by either partial oxidation of aqueous H2S by O2 or by the reaction of higher oxidation state sulfur species that are reactive with H2S at the conditions of formation e.g., S2O32- but not SO42-. The temperature of formation of natural marcasite may be as high as 240°C (HANNINGTON and SCOTT, 1985), but preservation on a multimillion-year scale seems to require post-depositional temperatures of below about 160°C (RISING, 1973; MCKIBBEN and ELDERS, 1985).

  5. Bias Adjusted Precipitation Threat Scores

    Directory of Open Access Journals (Sweden)

    F. Mesinger

    2008-04-01

    Full Text Available Among the wide variety of performance measures available for the assessment of skill of deterministic precipitation forecasts, the equitable threat score (ETS might well be the one used most frequently. It is typically used in conjunction with the bias score. However, apart from its mathematical definition the meaning of the ETS is not clear. It has been pointed out (Mason, 1989; Hamill, 1999 that forecasts with a larger bias tend to have a higher ETS. Even so, the present author has not seen this having been accounted for in any of numerous papers that in recent years have used the ETS along with bias "as a measure of forecast accuracy".

    A method to adjust the threat score (TS or the ETS so as to arrive at their values that correspond to unit bias in order to show the model's or forecaster's accuracy in extit{placing} precipitation has been proposed earlier by the present author (Mesinger and Brill, the so-called dH/dF method. A serious deficiency however has since been noted with the dH/dF method in that the hypothetical function that it arrives at to interpolate or extrapolate the observed value of hits to unit bias can have values of hits greater than forecast when the forecast area tends to zero. Another method is proposed here based on the assumption that the increase in hits per unit increase in false alarms is proportional to the yet unhit area. This new method removes the deficiency of the dH/dF method. Examples of its performance for 12 months of forecasts by three NCEP operational models are given.

  6. Municipal service provision in rural communities

    DEFF Research Database (Denmark)

    Nørgaard, Helle

    Municipal service provision in rural communities  EU policies for rural development stress the importance of investments rather than subsidies and aim at integrating different sectoral policies in order to improve the coherence and effectiveness of public expenditure. Policies also emphasize...... a place-based approach for rural development and thereby setting a competitive framework for local development. Rural municipalities are challenged due to demographic changes and population decline and consequently need to adjust municipal services. In this respect it is stressed that service provision...... communities. The paper further discusses whether rural municipalities can plan strategically, manage service provision and support place bound potential in rural communities in light of a competitive framework for local development....

  7. Supervisor security provision: correlates and related mechanisms.

    Science.gov (United States)

    Lavy, Shiri

    2014-06-01

    Attachment security in relationships is associated with several positive outcomes. Recently, researchers have applied attachment theory to employee-supervisor relationships. Two studies examined associations of supervisors' provision of attachment-related security with work-related outcomes and related underlying mechanisms. Participants completed measures of their supervisors' security provisions and of their own job satisfaction, organizational commitment, burnout, and performance. Supervisors' security provisions were associated with positive work-related outcomes, which were mediated by closeness behaviors (Study 1; N = 150, M age = 33.3 yr., SD = 9.6). These associations were also mediated by employees' sense of meaning at work when the supervisor was of the same sex (Study 2; N = 120, M age = 26.5 yr., SD = 5.0). Findings supported attachment-related dynamics in employee-supervisor relationships and suggested psychological mechanisms underlying these effects. PMID:25074301

  8. 42 CFR 426.400 - Procedure for filing an acceptable complaint concerning a provision (or provisions) of an LCD.

    Science.gov (United States)

    2010-10-01

    ... concerning a provision (or provisions) of an LCD. 426.400 Section 426.400 Public Health CENTERS FOR MEDICARE... COVERAGE DETERMINATIONS AND LOCAL COVERAGE DETERMINATIONS Review of an LCD § 426.400 Procedure for filing an acceptable complaint concerning a provision (or provisions) of an LCD. (a) The complaint....

  9. Use of polyaspartate as inhibitor of tartaric precipitations in wines.

    Science.gov (United States)

    Bosso, Antonella; Panero, Loretta; Petrozziello, Maurizio; Sollazzo, Marco; Asproudi, Andriani; Motta, Silvia; Guaita, Massimo

    2015-10-15

    All additives used to stabilize wines against the precipitations of potassium bitartrate have some limits: metatartaric acid (MTA) is effective but very unstable, carboxymethylcellulose is stable and effective in white wines but affects color stability in red wines, mannoproteins have a variable effectiveness depending on wine composition. This work was aimed at testing the effect of new stabilizing products on tartaric precipitations, focusing on the use of Na and K polyaspartate salts (PASPs). The effectiveness of 4 different PASPs and 1 MTA added to red and white wines was compared using the mini-contact test and cold test. The dose effect and the stability of the products over time were also studied. The PASPs showed a similar stabilizing effect and a longer stability over time compared to MTA. PASPs can be considered interesting as additives for wine tartaric stabilization. Further work is in progress to better characterize their enological properties.

  10. Experimental study of diffuse auroral precipitations

    International Nuclear Information System (INIS)

    First chapter is devoted to low energy electron precipitation in the evening sector of the auroral magnetosphere, during quiet and disturbed magnetic periods. Four subjects are studied in detail: the latitude distribution of the varied auroral forms and their relations to external magnetosphere; the time coefficients related to precipitations, the form and the dynamic of the diffuse precipitation equatorial frontier; the precipitation effect on the ionosphere concentration. The last part of the chapter shows that the plasma convection in the magnetosphere, associated to wave-particle interactions near the equatorial accounts for the principal characteristics of the evening sector diffuse electronic precipitations. The second chapter deals with subauroral precipitations of low energy ions, after the magnetospheric substorms, in the high latitude regions of the morning sector

  11. Estimating Global Precipitation for Science and Application

    Science.gov (United States)

    Huffman, George J.

    2013-01-01

    Over the past two decades there has been vigorous development in the satellite assets and the algorithms necessary to estimate precipitation around the globe. In particular the highly successful joint NASAJAXA Tropical Rainfall Measuring Mission (TRMM) and the upcoming Global Precipitation Measurement (GPM) mission, also joint between NASA and JAXA, have driven these issues. At the same time, the long-running Global Precipitation Climatology Project (GPCP) continues to extend a stable, climate-oriented view of global precipitation. This talk will provide an overview of these projects and the wider international community of precipitation datasets, sketch plans for next-generation products, and provide some examples of the best use for the different products. One key lesson learned is that different data sets are needed to address the variety of issues that need precipitation data, including detailed 3-D views of hurricanes, flash flood forecasting, drought analysis, and global change.

  12. Photochemical precipitation of thorium and cerium and their separation from other ions in aqueous solution.

    Science.gov (United States)

    Das, M; Heyn, A H; Hoffman, M Z; Agarwal, R P

    1970-10-01

    Thorium was precipitated from homogeneous solution by exposing solutions of thorium and periodate in dilute perchloric acid to 253.7 nm radiation from a low-pressure mercury lamp. Periodate is reduced photochemically to iodate which causes the formation of a dense precipitate of the basic iodate of thorium(IV). The precipitate was redissolved, the iodate reduced, the thorium precipitated first as the hydroxide, then as the oxalate and ignited to the dioxide for weighing. Thorium(IV) solutions containing 8-200 mg of ThO(2) gave quantitative results with a standard deviation (s) of 0.2 mg. Separations from 25 mg each of iron, calcium, magnesium, 50 mg of yttrium and up to 500 mg of uranium(VI) were quantitative (s = 0.25 mg). Separations from rare earths, except cerium, were accomplished by using hexamethylenetetramine rather than ammonia for the precipitation of the hydroxide. Cerium(III) was similarly precipitated and converted into CeO(2) for weighing. Quantitative results were obtained for 13-150 mg of CeO(2) with a standard deviation of 0.2 mg. Separations from 200 mg of uranium were quantitative. Other rare earths and yttrium interfered seriously. The precipitates of the basic cerium(IV) and thorium iodates obtained are more compact than those obtained by direct precipitation and can be handled easily. Attempts to duplicate Suzuki's method for separating cerium from neodymium and yttrium were not successful. PMID:18960820

  13. Spatial Distribution of Precipitation in Lithuania

    Directory of Open Access Journals (Sweden)

    Viktorija Grušaitė

    2011-04-01

    Full Text Available Analysis is based on a 36-year record (1971–2006 of daily precipitation at 17 meteorological stations throughout Lithuania. The obtained data was used to investigate the spatial properties of the precipitation fields of monthly decadals (10-days. The average, minimum and maximum correlation coefficients of decadals were estimated. A spatial correlation of precipitation was created among all meteorological stations in Lithuania.Article in Lithuanian

  14. Spatial Distribution of Precipitation in Lithuania

    OpenAIRE

    Viktorija Grušaitė

    2011-01-01

    Analysis is based on a 36-year record (1971–2006) of daily precipitation at 17 meteorological stations throughout Lithuania. The obtained data was used to investigate the spatial properties of the precipitation fields of monthly decadals (10-days). The average, minimum and maximum correlation coefficients of decadals were estimated. A spatial correlation of precipitation was created among all meteorological stations in Lithuania.Article in Lithuanian

  15. Improved Electronic Control for Electrostatic Precipitators

    Science.gov (United States)

    Johnston, D. F.

    1986-01-01

    Electrostatic precipitators remove particulate matter from smoke created by burning refuse. Smoke exposed to electrostatic field, and particles become electrically charged and migrate to electrically charged collecting surfaces. New microprocessor-based electronic control maintains precipitator power at maximum particulate-collection level. Control automatically senses changes in smoke composition due to variations in fuel or combustion and adjusts precipitator voltage and current accordingly. Also, sensitive yet stable fault detection provided.

  16. Observation of solid precipitation using satellite gravity

    Science.gov (United States)

    Seo, K.; Waliser, D. E.; Ryu, D.; Tian, B.; Kim, B.

    2009-12-01

    Understanding hydrological processes in the arctic region and their variation are emerging and important issues in the association with global climate changes. Solid precipitation is particularly important because it plays a major role in controlling the winter hydrological cycle and spring discharge. Nevertheless, observations of winter snowfall in high latitudes is challenging due to sharply decreasing numbers of precipitation gauges and gauge measurement biases. In addition, conventional satellite methods that work well in low-latitudes are unsuitable for the high latitude conditions. In this study, we present a new method of estimating winter snowfall in the arctic region with GRACE time varying gravity measurements. In northern high latitudes, it is very cold in winter, and thus solid precipitation accumulates with very limited melting and evapotranspiration. Therefore, observed gravity increments during winter mainly result from solid precipitation. We estimate amount of solid precipitation during winter (DJF) from four major arctic basins, Mackenzie, Lena, Yenisei and Ob. New estimates using satellite gravity are compared to global satellite and reanalysis precipitation products , which are GPCP, CMAP, NCEP/NCAR, ECMWF and JCDAS. GRACE-based estimates of snowfall are very close to those of CMAP, ECMWF and JCDAS. We extend the methodology to examine spatial distribution of solid precipitation in the pan-arctic land areas, which shows a good agreement with JCDAS. This new measurement of solid precipitation can provide an altogether new form of observations for hydrological cycle research studies, model and precipitation product evaluation and data assimilation efforts.

  17. Recovery of zinc and manganese, and other metals (Fe, Cu, Ni, Co, Cd, Cr, Na, K) from Zn-MnO2 and Zn-C waste batteries: Hydroxyl and carbonate co-precipitation from solution after reducing acidic leaching with use of oxalic acid

    Science.gov (United States)

    Sobianowska-Turek, A.; Szczepaniak, W.; Maciejewski, P.; Gawlik-Kobylińska, M.

    2016-09-01

    The article discusses the current situation of the spent batteries and portable accumulators management. It reviews recycling technologies of the spent batteries and portable accumulators which are used in the manufacturing installations in the world. Also, it presents the authors' research results on the reductive acidic leaching of waste material of the zinc-carbon batteries (Zn-C) and zinc-manganese batteries (alkaline Zn-MnO2) delivered by a company dealing with mechanical treatment of this type of waste stream. The research data proved that the reductive acidic leaching (H2SO4 + C2H2O4) of the battery's black mass allows to recover 85.0% of zinc and 100% of manganese. Moreover, it was found that after the reductive acidic leaching it is possible to recover nearly 100% of manganese, iron, cadmium, and chromium, 98.0% of cobalt, 95.5% of zinc, and 85.0% of copper and nickel from the solution with carbonate method. On the basis of the results, it is possible to assume that the carbonate method can be used for the preparation of manganese-zinc ferrite.

  18. Preparation of polyethylene sacks for collection of precipitation samples for chemical analysis

    Science.gov (United States)

    Schroder, L.J.; Bricker, A.W.

    1985-01-01

    Polyethylene sacks are used to collect precipitation samples. Washing polyethylene with acetone, hexane, methanol, or nitric acid can change the adsorptive characteristics of the polyethylene. In this study, simulated precipitation at pH 4.5 was in contact with the polyethylene sacks for 21 days; subsamples were removed for chemical analysis at 7, 14, and 21 days after intitial contact. Sacks washed with acetone adsorbed iron and lithium; sacks washed with hexane adsorbed barium, iron , and lithium; sacks washed with methanol adsorbed calcium and iron; and sacks washed with 0.30 N nitric acid adsorbed iron. Leaching the plastic sacks with 0.15 N nitric acid did not result in 100-percent recovery of any of the adsorbed metals. Washing polyethylene sacks with dilute nitric acid caused the pH of the simulated precipitation to be decreased by 0.2 pH unit after 1 week of contact with the polyethylene. The specific conductance increased by 10 microsiemens per centimeter. Contamination of precipitation samples by lead was determined to be about 0.1 microgram per liter from contact with precleaned polyethylene sacks. No measurable contamination of precipitation samples by zinc occurred. (USGS)

  19. Shifting covariability of North American summer monsoon precipitation with antecedent winter precipitation

    Science.gov (United States)

    McCabe, G.J.; Clark, M.P.

    2006-01-01

    Previous research has suggested that a general inverse relation exists between winter precipitation in the southwestern United states (US) and summer monsoon precipitation. In addition, it has been suggested that this inverse relation between winter precipitation and the magnitude of the southwestern US monsoon breaks down under certain climatic conditions that override the regional winter/monsoon precipitation relations. Results from this new study indicate that the winter/monsoon precipitation relations do not break down, but rather shift location through time. The strength of winter/monsoon precipitation relations, as indexed by 20-year moving correlations between winter precipitation and monsoon precipitation, decreased in Arizona after about 1970, but increased in New Mexico. The changes in these correlations appear to be related to an eastward shift in the location of monsoon precipitation in the southwestern US. This eastward shift in monsoon precipitation and the changes in correlations with winter precipitation also appear to be related to an eastward shift in July/August atmospheric circulation over the southwestern US that resulted in increased monsoon precipitation in New Mexico. Results also indicate that decreases in sea-surface temperatures (SSTs) in the central North Pacific Ocean also may be associated with th changes in correlations between winter and monsoon precipitation. Copyright ?? 2006 Royal Meteorological Society.

  20. 42 CFR 423.562 - General provisions.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false General provisions. 423.562 Section 423.562 Public... them through the Part D plan sponsor; and (ii) Complaint process available to the enrollee under the... this subpart to the extent they are appropriate. (d) Relation to ERISA Requirements. Consistent...

  1. 31 CFR 25.400 - Loan provisions.

    Science.gov (United States)

    2010-07-01

    ... FEDERAL FINANCING BANK AND GUARANTEED BY THE DEFENSE SECURITY ASSISTANCE AGENCY Form of Private Loan § 25... criteria: (i) The Private Loan shall have one set of semi-annual payment dates; (ii) Interest on and... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Loan provisions. 25.400 Section...

  2. 7 CFR 249.25 - Other provisions.

    Science.gov (United States)

    2010-01-01

    ... Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS SENIOR FARMERS' MARKET NUTRITION PROGRAM (SFMNP) Miscellaneous Provisions § 249... (7 U.S.C. 2011, et seq.) and to any other Federal or State food or nutrition assistance program....

  3. Advance Provision of Emergency Contraception for Adolescents

    Science.gov (United States)

    Adamji, Jehan-Marie; Swartwout, Kathryn

    2010-01-01

    Emergency contraception is most effective at preventing unintended pregnancy when taken as early as possible following unprotected sexual intercourse. Advance provision of this medication supports more timely and effective use. In the midst of rising teen pregnancy rates, current policies often limit access to emergency contraception for…

  4. 48 CFR 5215.407 - Solicitation provisions.

    Science.gov (United States)

    2010-10-01

    ... obtain cost or pricing data. Contracting officers must be judicious in the use of the Alternate I provision, as it may cause offerors to incur certain costs in preparing standby cost or pricing data in... that adequate price competition will exist. If it is anticipated that an award will be based...

  5. 22 CFR 226.48 - Contract provisions.

    Science.gov (United States)

    2010-04-01

    ... authority as acceptable sureties pursuant to 31 CFR part 223, “Surety Companies Doing Business with the... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Contract provisions. 226.48 Section 226.48 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S....

  6. Block Grants: Federal Data Collection Provisions.

    Science.gov (United States)

    General Accounting Office, Washington, DC. Div. of Human Resources.

    This fact sheet compares statutory data collection and reporting provisions of the federal education block grant (chapter 2 of the Education Consolidation and Improvement Act of 1981) with the nine other block grant programs funded in fiscal year 1986; data on statutory administrative cost limits are also provided. Each grant's legislation was…

  7. 5 CFR 841.1006 - Additional provisions.

    Science.gov (United States)

    2010-01-01

    ... of the second month following the month in which it is received, but incurs no liability or... will issue an accounting. If the State finds this accounting unacceptable, it may then and only then... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Additional provisions. 841.1006...

  8. 5 CFR 534.506 - Conversion provisions.

    Science.gov (United States)

    2010-01-01

    ... conversion, other than to the minimum rate under 5 U.S.C. 5376, the increase must be approved by the head of... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Conversion provisions. 534.506 Section... OTHER SYSTEMS Pay for Senior-Level and Scientific and Professional Positions § 534.506...

  9. 40 CFR 61.173 - Compliance provisions.

    Science.gov (United States)

    2010-07-01

    ...) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Inorganic Arsenic Emissions From Primary Copper Smelters § 61.173 Compliance provisions. (a) The owner or operator of each copper converter to which § 61.172(b)-(f) applies shall demonstrate compliance with the requirements...

  10. 7 CFR 1485.23 - Miscellaneous provisions.

    Science.gov (United States)

    2010-01-01

    ... provisions of the Freedom of Information Act (FOIA), 5 U.S.C. 552, 7 CFR part 1, Subpart A—Official Records... provided that it applies any exchange allowance, insurance proceeds or sales proceeds toward the purchase..., cost of purchase, replacement value, serial number, make, model, and electrical requirements. (3)...

  11. Annual Training Activity Report (ATAR) - Provision ITN

    OpenAIRE

    Ricordel, Vincent

    2015-01-01

    The document provides a first vision of the PROVISION (PeRceptually Optimised Video CompresSION) ITN project after few months of activity (only 14% of the fellows.month have been engaged) since its kick-off. The report summarizes the training activities performed in the Project for the period from 01/09/2013 to 01/10/2014.

  12. Music Provision in UK Public Libraries

    Science.gov (United States)

    Dorney, Carl; McKnight, Cliff

    2004-01-01

    Public library music provision, as a less traditional role for public libraries, has always caused contention: a vital source of cultural materials within the community though never confirmed to be a core part of library services by the Government. This article concerns itself with a detailed consideration of the decline of music services over the…

  13. 10 CFR 905.34 - Adjustment provisions.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Adjustment provisions. 905.34 Section 905.34 Energy DEPARTMENT OF ENERGY ENERGY PLANNING AND MANAGEMENT PROGRAM Power Marketing Initiative § 905.34 Adjustment... continue to take place based on existing contract/marketing criteria principles....

  14. LOCAL GOVERNANCE AND PUBLIC GOODS PROVISION

    OpenAIRE

    Zhang, Xiaobo; Fan, Shenggen; Zhang, Linxiu; Huang, Jikun

    2001-01-01

    Since the early nineties, tens of thousands of villages have held elections of their leaders in rural China. Using a recent village survey, this paper empirically examines the impact of election on public goods provision to the rural community. We found that elected officials tend to tax less on constituents and provide them more with public services.

  15. 40 CFR 1033.501 - General provisions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false General provisions. 1033.501 Section 1033.501 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS... specified in this subpart, use the equipment and procedures for compression-ignition engines in 40 CFR...

  16. 46 CFR 502.501 - General provisions.

    Science.gov (United States)

    2010-10-01

    ... FEDERAL MARITIME COMMISSION GENERAL AND ADMINISTRATIVE PROVISIONS RULES OF PRACTICE AND PROCEDURE... in section 15(a) of the Agricultural Marketing Act (12 U.S.C. 1141j(a)) with not more than 500... in bad faith, or special circumstances make an award unjust. (f) Allowable fees and expenses....

  17. 28 CFR 105.27 - Miscellaneous provisions.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Miscellaneous provisions. 105.27 Section 105.27 Judicial Administration DEPARTMENT OF JUSTICE (CONTINUED) CRIMINAL HISTORY BACKGROUND CHECKS... national fingerprint-based criminal history checks of prospective and current private security officers...

  18. Rethinking knowledge provision for the marginalized

    DEFF Research Database (Denmark)

    Schad, Iven; Thai Thi, Minh; Hoffmann, Volker;

    2013-01-01

    of this chapter are to (a) provide an overview of the historical development of rural advisory and knowledge provision in Vietnam, and how legal frameworks have changed over time, (b) demonstrate how more client-centered extension approaches can be translated and utilized at the field level, and (c) focus...

  19. 49 CFR 172.102 - Special provisions.

    Science.gov (United States)

    2010-10-01

    ... and other solid propellants that are used as powder for small arms and have been classed as Division 1... substances, liquid or solid, n.o.s.”, as appropriate. In addition, for solid materials, special provision B54 applies. 9Packaging for certain PCBs for disposal and storage is prescribed by EPA in 40 CFR 761.60...

  20. Cloud-based Collaborative Business Services Provision

    NARCIS (Netherlands)

    L.M. Camarinha-Matos; H. Afsarmanesh; A.I. Oliveira; F. Ferrada

    2013-01-01

    The notion of service-enhanced product, representing the association of services to manufactured products, offers an important mechanism for value creation and product differentiation. This is particularly relevant in the case of complex, highly customized and long-life products. Provision of suitab

  1. 40 CFR 65.119 - Recordkeeping provisions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 15 2010-07-01 2010-07-01 false Recordkeeping provisions. 65.119 Section 65.119 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... assessment that identifies the representative composition of the process fluid. The assessment shall be...

  2. 18 CFR 35.23 - General provisions.

    Science.gov (United States)

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false General provisions. 35.23 Section 35.23 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION... rate schedule on file that expressly provides for the recovery of all incremental or...

  3. 12 CFR 404.1 - General provisions.

    Science.gov (United States)

    2010-01-01

    ... Bank maintains an Internet site at http://www.exim.gov. The site contains information on Ex-Im Bank... 12 Banks and Banking 4 2010-01-01 2010-01-01 false General provisions. 404.1 Section 404.1 Banks and Banking EXPORT-IMPORT BANK OF THE UNITED STATES INFORMATION DISCLOSURE Procedures for...

  4. 20 CFR 340.1 - Statutory provisions.

    Science.gov (United States)

    2010-04-01

    ... Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD UNEMPLOYMENT INSURANCE ACT RECOVERY OF BENEFITS § 340.1 Statutory provisions. (a) Section 2(d) of the Railroad Unemployment Insurance... 1937, or insurance benefits under title II of the Social Security Act, or unemployment, maternity,...

  5. 40 CFR 65.66 - Recordkeeping provisions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 15 2010-07-01 2010-07-01 false Recordkeeping provisions. 65.66 Section 65.66 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... records. The owner or operator shall maintain records of measurements, engineering assessments,...

  6. Circulation factors affecting precipitation over Bulgaria

    Science.gov (United States)

    Nojarov, Peter

    2015-09-01

    The objective of this paper is to determine the influence of circulation factors on precipitation in Bulgaria. The study succeeds investigation on the influence of circulation factors on air temperatures in Bulgaria, as the focus here is directed toward precipitation amounts. Circulation factors are represented through two circulation indices, showing west-east or south-north transport of air masses over Bulgaria and four teleconnection indices (patterns)—North Atlantic Oscillation, East Atlantic, East Atlantic/Western Russia, and Scandinavian. Omega values at 700-hPa level show vertical motions in the atmosphere. Annual precipitation trends are mixed and not statistically significant. A significant decrease of precipitation in Bulgaria is observed in November due to the strengthening of the eastward transport of air masses (strengthening of EA teleconnection pattern) and anticyclonal weather (increase of descending motions in the atmosphere). There is also a precipitation decrease in May and June due to the growing influence of the Azores High. An increase of precipitation happens in September. All this leads to a redistribution of annual precipitation course, but annual precipitation amounts remain the same. However, this redistribution has a negative impact on agriculture and winter ski tourism. Zonal circulation has a larger influence on precipitation in Bulgaria compared to meridional. Eastward transport throughout the year leads to lower than the normal precipitation, and vice versa. With regard to the four teleconnection patterns, winter precipitation in Bulgaria is determined mainly by EA/WR teleconnection pattern, spring and autumn by EA teleconnection pattern, and summer by SCAND teleconnection pattern.

  7. Mean Annual Precipitation in West-Central Nevada using the Precipitation-Zone Method

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set contains 1971-2000 mean annual precipitation estimates for west-central Nevada. This is a raster data set developed using the precipitation-zone...

  8. Precipitated silica as flow regulator.

    Science.gov (United States)

    Müller, Anne-Kathrin; Ruppel, Joanna; Drexel, Claus-Peter; Zimmermann, Ingfried

    2008-08-01

    Flow regulators are added to solid pharmaceutical formulations to improve the flow properties of the powder mixtures. The primary particles of the flow regulators exist in the form of huge agglomerates which are broken down into smaller aggregates during the blending process. These smaller aggregates adsorb at the surface of the solid's grains and thus diminish attractive Van-der-Waals-forces by increasing the roughness of the host's surface. In most cases amorphous silica is used as flow additive but material properties like particle size or bond strength influence the desagglomeration tendency of the agglomerates and thus the flow regulating potency of each silica. For some silica types we will show that the differences in their flow regulating potency are due to the rate and extent by which they are able to cover the surface of the host particles. Binary powder mixtures consisting of a pharmaceutical excipient and an added flow regulator were blended in a Turbula mixer for a defined period of time. As pharmaceutical excipient corn starch was used. The flow regulators were represented by a selection of amorphous silicon dioxide types like a commercial fumed silica and various types of SIPERNAT precipitated silica provided by Evonik-Degussa GmbH, Hanau, Germany. Flowability parameters of the mixtures were characterized by means of a tensile strength tester. The reduction of tensile strength with the blending time can be correlated with an increase in fragmentation of the flow regulator. PMID:18595668

  9. The influence of mountain meteorology on precipitation chemistry at low and high elevations of the Colorado Front Range, USA

    Science.gov (United States)

    Denning, A. Scott

    1993-01-01

    We explored the seasonal characteristics in wet deposition chemistry for two sites located at different elevations along the east slope of the Colorado Front Range in Rocky Mountain National Park. Seasonally separated precipitation was stratified into highly concentrated (high salt), dilute (low salt), or acid-dominated precipitation groups. These groups and unstratified precipitation data were related to mean easterly or westerly zonal winds to determine direction of local transport. Strong acid anion associations were also determined for the stratified and unstratified precipitation data sets. We found that strong acid anions, acidity, ammonium, and high salt concentrations originate to the east of Rocky Mountain National Park, and are transported via up-valley funneling winds or convective instability from differential heating of the mountains and the plains to the east. These influence the composition of precipitation at Beaver Meadows, the low elevation site, throughout the year, while their effect on precipitation at Loch Vale, the high elevation site, is felt most strongly during the summer. During the winter, Loch Vale precipitation is very dilute, and occurs in conjunction with westerly winds resulting from the southerly location of the jet stream.

  10. Effects of aqueous complexation on reductive precipitation of uranium by Shewanella putrefaciens

    Directory of Open Access Journals (Sweden)

    Northup Abraham

    2004-10-01

    Full Text Available We have examined the effects of aqueous complexation on rates of dissimilatory reductive precipitation of uranium by Shewanella putrefaciens. Uranium(VI was supplied as sole terminal electron acceptor to Shewanella putrefaciens (strain 200R in defined laboratory media under strictly anaerobic conditions. Media were amended with different multidentate organic acids, and experiments were performed at different U(VI and ligand concentrations. Organic acids used as complexing agents were oxalic, malonic, succinic, glutaric, adipic, pimelic, maleic, citric, and nitrilotriacetic acids, tiron, EDTA, and Aldrich humic acid. Reductive precipitation of U(VI, resulting in removal of insoluble amorphous UO2 from solution, was measured as a function of time by determination of total dissolved U. Reductive precipitation was measured, rather than net U(VI reduction to U(IV, to assess overall U removal rates from solution, which may be used to gauge the influence of chelation on microbial U mineralization. Initial linear rates of U reductive precipitation were found to correlate with stability constants of 1:1 aqueous U(VI:ligand and U(IV:ligand complexes. In the presence of strongly complexing ligands (e.g., NTA, Tiron, EDTA, UO2 precipitation did not occur. Our results are consistent with ligand-retarded precipitation of UO2, which is analogous to ligand-assisted solid phase dissolution but in reverse: ligand exchange with the U4+ aquo cation acts as a rate-limiting reaction moderating coordination of water molecules with U4+, which is a necessary step in UO2 precipitation. Ligand exchange kinetics governing dissociation rates of ligands from U(VI-organic complexes may also influence overall UO2 production rates, although the magnitude of this effect is unclear relative to the effects of U(IV-organic complexation. Our results indicate that natural microbial-aqueous systems containing abundant organic matter can inhibit the formation of biogenic amorphous UO2.

  11. Impacts of extreme precipitation and seasonal changes in precipitation on plants

    Directory of Open Access Journals (Sweden)

    M. J. B. Zeppel

    2013-10-01

    Full Text Available The hydrological cycle is predicted to become more intense in future climates, with both larger precipitation events and longer times between events. Redistribution of precipitation may occur both within and across seasons, and the resulting wide fluctuations in soil water content may dramatically affect plants. Though these responses remain poorly understood, recent research in this emerging field suggests the effects of redistributed precipitation may differ from predictions based on previous drought studies. We review available studies on both extreme precipitation (redistribution within seasons and seasonal changes in precipitation (redistribution across seasons on grasslands and forests. Extreme precipitation differentially affected Aboveground Net Primary Productivity (ANPP, depending on whether extreme precipitation led to increased or decreased soil water content (SWC, which differed based on the current precipitation at the site. Specifically, studies to date reported that extreme precipitation decreased ANPP in mesic sites, but, conversely, increased ANPP in xeric sites, suggesting that plant available water is a key factor driving responses to extreme precipitation. Similarly, the effects of seasonal changes in precipitation on ANPP, phenology, and leaf and fruit development varied with the effect on SWC. Reductions in spring or summer generally had negative effects on plants, associated with reduced SWC, while subsequent reductions in autumn or winter had little effect on SWC or plants. Similarly, increased summer precipitation had a more dramatic impact on plants than winter increases in precipitation. The patterns of response suggest xeric biomes may respond positively to extreme precipitation, while comparatively mesic biomes may be more likely to be negatively affected. And, seasonal changes in precipitation during warm or dry seasons may have larger effects than changes during cool or wet seasons. Accordingly, responses to

  12. Equilibrium Model of Precipitation in Microalloyed Steels

    Science.gov (United States)

    Xu, Kun; Thomas, Brian G.; O'Malley, Ron

    2011-02-01

    The formation of precipitates during thermal processing of microalloyed steels greatly influences their mechanical properties. Precipitation behavior varies with steel composition and temperature history and can lead to beneficial grain refinement or detrimental transverse surface cracks. This work presents an efficient computational model of equilibrium precipitation of oxides, sulfides, nitrides, and carbides in steels, based on satisfying solubility limits including Wagner interaction between elements, mutual solubility between precipitates, and mass conservation of alloying elements. The model predicts the compositions and amounts of stable precipitates for multicomponent microalloyed steels in liquid, ferrite, and austenite phases at any temperature. The model is first validated by comparing with analytical solutions of simple cases, predictions using the commercial package JMat-PRO, and previous experimental observations. Then it is applied to track the evolution of precipitate amounts during continuous casting of two commercial steels (1004 LCAK and 1006Nb HSLA) at two different casting speeds. This model is easy to modify to incorporate other precipitates, or new thermodynamic data, and is a useful tool for equilibrium precipitation analysis.

  13. The trends of global tritium precipitations

    International Nuclear Information System (INIS)

    The trends of global tritium precipitation from 1953 to 1979 were estimated based on the tritium data published in seven volumes of Environmental Isotope Data by the International Atomic Energy Agency (IAEA). Tritium precipitation samples were collected from 342 stations in the world and tritium concentrations were measured by IAEA and 27 laboratories. Due to repeated atomospheric nuclear explosions, tritium precipitations showed maximum peak in 1963. After the agreement of the Partial Test Ban Treaty in 1964, they have gradually decreased until now showing seasonal variations. To obtain clear trends of tritium precipitations, seasonal and irregular factors were eliminated from the original time-series data using a code developed by the Japanese Economic Planning Agency. Results of analyses were as follows; a) Peak concentrations and precipitations of tritium were observed every year around the period of late spring to summer. b) The maximum annual tritium concentration and precipitation were observed in 1963 for northern hemisphere stations. c) A latitude effect was observed in the northern hemisphere. The maximum concentrations and precipitations were seen at the latitude of approximately 50 deg N. d) Continental stations always showed higher tritium concentrations and precipitations than comparable maritime stations. (author)

  14. CLIMATIC CHARACTERISTICS OF TYPHOON PRECIPITATION OVER CHINA

    Institute of Scientific and Technical Information of China (English)

    WANG Yong-mei; REN Fu-min; LI Wei-jing; WANG Xiao-ling

    2008-01-01

    The spatio-temporal characteristics of typhoon precipitation over China are analyzed in this study. The results show that typhoon precipitation covers most of central-eastern China. Typhoon precipitation gradually decreases from the southeastern coastal regions to the northwestern mainland. The maximum annual typhoon precipitation exceeds 700 mm in central-eastern Taiwan and part of Hainan, while the minimum annual typhoon precipitation occurs in parts of Inner Mongolia, Shanxi, Shaanxi and Sichuan, with values less than 10 mm. Generally, typhoons produce precipitation over China during April - December with a peak in August. The annual typhoon precipitation time series for observation stations are examined for long-term trends. The results show that decreasing trends exist in most of the stations from 1957 to 2004 and are statistically significant in parts of Taiwan, Hainan, coastal Southeast China and southern Northeast China. The anomaly of typhoon precipitation mainly results from that of the general circulation over Asia and the Walker Cell circulation over the equatorial central and eastern Pacific. Typhoon torrential rain is one of the extreme rainfall events in the southeastern coastal regions and parts of central mainland. In these regions, torrential rains are mostly caused by typhoons.

  15. Study of asphaltene precipitation by Calorimetry

    DEFF Research Database (Denmark)

    Verdier, Sylvain Charles Roland; Plantier, Frédéric; Bessières, David;

    2007-01-01

    of experiments showed that weak forces determine precipitation. Indeed, isothermal titration calorimetry could not detect any clear signal although this technique can detect low-energy transitions such as liquid-liquid equilibrium and rnicellization. The second series of tests proved that precipitation caused...

  16. Spatial Aspects of the Provision of Forest Ecosystem Services

    DEFF Research Database (Denmark)

    Nielsen, Anne Sofie Elberg

    The research objective of this thesis is to examine the importance of spatial landscape patterns for the provision of forest ecosystem services and the implications for effective land management and policy decisions. This thesis presents four papers providing different approaches...... to the incorporation of spatial factors into cost and benefit evaluation of FES provision. Focus is on assessing where forest ecosystem provision should be undertaken, determinants of private stakeholder provision efforts and welfare consequences of changes in the provision level. Provision of carbon sequestration...

  17. A thermal responsive affinity ligand for precipitation of sialylated proteins

    Directory of Open Access Journals (Sweden)

    Lindsay Arnold

    2016-01-01

    Full Text Available We report here the development of a thermal responsive affinity ligand specific to sialic acid, sialic acid containing oligosaccharides, glycoproteins, and other sialylated glycoconjugates. The ligand is a fusion protein of 40 repeats of pentapeptide of an elastin like polymer (ELP and the 21 kD sialic acid binding domain of a Vibrio cholera neuraminidase (VCNA. For cost-effective synthesis, the fusion protein was targeted to the periplasmic space of an E. coli lpp deletion mutant, resulting in its secretion to the growth medium. A pre-induction heat-shock step at 42 ˚C for 20 minutes was necessary to achieve high level expression of the ligand. Under optimized induction condition (18 ˚C, 0.1 mM IPTG and 48 hours of post-induction cultivation, the ligand was produced to about 100 mg/L. The ligand exhibited a transition temperature of 52 ˚C, which could be depressed to 37 ˚C with the addition of 0.5 M NaCl. Using fetuin as a model sialylated protein, the ligand was applied in an affinity precipitation process to illustrate its potential application in glycoprotein isolation. The ligand captured 100% fetuin from an aqueous solution when the molar ratio of ligand to fetuin was 10 to 1, which was lower than the expected for full titration of sialic acid on the glycoprotein by the lectin. Elution of fetuin from ligand was achieved with PBS buffer containing 2 mM sialic acid. To evaluate how protein and other contaminants influence the recovery of sialylated proteins, CHO medium was spiked into the fetuin solution. The predominant protein species in CHO medium was found to be albumin. Although its removal of over 94% was evident, purified fetuin contained some albumin due to its over-abundance. Additional experiments with albumin contaminant of varying concentrations showed that below 1 mg/L, albumin had no impact on the affinity precipitation, whereas above 10 mg/L, some albumin was co-purified with fetuin. However, even at 50 mg/ml, fetuin

  18. Global precipitations and climate change. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Desbois, M. (ed.) (Ecole Polytechnique, 91 - Palaiseau (France). Lab. de Meteorologie Dynamique); Desalmand, F. (ed.) (Ecole Polytechnique, 91 - Palaiseau (France). Lab. de Meteorologie Dynamique)

    1994-01-01

    The workshop reviewed the present status of knowledge concerning the past and present evolution of the distribution of precipitations at global scale, related to climate evolution at different time scales. This review was intended to assess the availability and quality of data which could help, through validation and initialization of model studies, to improve our understanding of the processes determining these precipitation changes. On another hand, the modelling specialists presented their actual use of precipitation data. Exchanges of views between the modelling and observing communities were thus made possible, leading to a set of recommendations for future studies. Sessions were then devoted to specific themes: (1) Paleoclimatology, (2) data collection, history and statistics, programmes, (3) methodologies and accuracy of large scale estimation of precipitation from conventional data, (4) estimation of precipitation from satellite data, (5) modelling studies. (orig.)

  19. Global precipitations and climate change. Proceedings

    International Nuclear Information System (INIS)

    The workshop reviewed the present status of knowledge concerning the past and present evolution of the distribution of precipitations at global scale, related to climate evolution at different time scales. This review was intended to assess the availability and quality of data which could help, through validation and initialization of model studies, to improve our understanding of the processes determining these precipitation changes. On another hand, the modelling specialists presented their actual use of precipitation data. Exchanges of views between the modelling and observing communities were thus made possible, leading to a set of recommendations for future studies. Sessions were then devoted to specific themes: 1) Paleoclimatology, 2) data collection, history and statistics, programmes, 3) methodologies and accuracy of large scale estimation of precipitation from conventional data, 4) estimation of precipitation from satellite data, 5) modelling studies. (orig.)

  20. Acid Rain Students Do Original Research.

    Science.gov (United States)

    Outdoor Communicator, 1984

    1984-01-01

    At Park Senior High School (Cottage Grove, Minnesota), 46 juniors and seniors planted 384 red pine seedlings in connection with their original research on acid rain, with advice from Dr. Harriet Stubbs, director of the Acid Precipitation Awareness Program (West Saint Paul), which has been developing acid rain teaching materials. (MH)

  1. Probabilistic Precipitation Estimation with a Satellite Product

    Directory of Open Access Journals (Sweden)

    Nir Y. Krakauer

    2015-04-01

    Full Text Available Satellite-based precipitation products have been shown to represent precipitation well over Nepal at monthly resolution, compared to ground-based stations. Here, we extend our analysis to the daily and subdaily timescales, which are relevant for mapping the hazards caused by storms as well as drought. We compared the Tropical Rainfall Measuring Mission (TRMM Multi-satellite Precipitation Analysis (TMPA 3B42RT product with individual stations and with the gridded APHRODITE product to evaluate its ability to retrieve different precipitation intensities. We find that 3B42RT, which is freely available in near real time, has reasonable correspondence with ground-based precipitation products on a daily timescale; rank correlation coefficients approach 0.6, almost as high as the retrospectively calibrated TMPA 3B42 product. We also find that higher-quality ground and satellite precipitation observations improve the correspondence between the two on the daily timescale, suggesting opportunities for improvement in satellite-based monitoring technology. Correlation of 3B42RT and 3B42 with station observations is lower on subdaily timescales, although the mean diurnal cycle of precipitation is roughly correct. We develop a probabilistic precipitation monitoring methodology that uses previous observations (climatology as well as 3B42RT as input to generate daily precipitation accumulation probability distributions at each 0.25° x 0.25° grid cell in Nepal and surrounding areas. We quantify the information gain associated with using 3B42RT in the probabilistic model instead of relying only on climatology and show that the quantitative precipitation estimates produced by this model are well calibrated compared to APHRODITE.

  2. Precipitation of Continental Origin over South America

    Science.gov (United States)

    Martinez-Agudelo, J. A.; Dominguez, F.

    2012-12-01

    The Amazon forest receives high amounts of moisture from the tropical Atlantic. A significant part of this moisture is returned back to the atmosphere by the forest, and further redistributed to the rest of the continent by the meridional flow imposed by the Andes. Thus, the land-atmosphere interaction between the Amazon forest and the large-scale flow affects not only the forest itself but also the downstream regions. We develop a method to quantify the precipitation of continental origin over South America, and identify the contribution that selected source regions make to continental precipitation. The average annual cycle of precipitation of continental origin for the five-year period 2000-2004 shows a band of high values aligned along the northwest-southeast direction, from southern Peru to northeastern Argentina. The lowest values of precipitation of continental origin occur upstream, over the northeastern coast of South America. Precipitation that originates as moisture from the Amazon forest shows maximum values over the western side of the Amazon, east of the Andes, especially over southern Peru. The Amazon forest also contributes to precipitation over La Plata River Basin (LPRB) and the Pacific coast of Colombia. During its dry season, up to 29.3% of the precipitation over LPRB originates as moisture from the Amazon forest. Throughout the year, the contributions to precipitation over LPRB by the Amazon forest and LPRB (recycled precipitation) are in the same range, but out of phase. The average contribution of the rest of the continent to precipitation over LPRB is smaller but of the same order as that of the Amazon and LPRB.

  3. Two-stage precipitation of neptunium (IV) oxalate

    International Nuclear Information System (INIS)

    Neptunium (IV) oxalate was precipitated using a two-stage precipitation system. A series of precipitation experiments was used to identify the significant process variables affecting precipitate characteristics. Process variables tested were input concentrations, solubility conditions in the first stage precipitator, precipitation temperatures, and residence time in the first stage precipitator. A procedure has been demonstrated that produces neptunium (IV) oxalate particles that filter well and readily calcine to the oxide

  4. Plasma proteome coverage is increased by unique peptide recovery from sodium deoxycholate precipitate.

    Science.gov (United States)

    Serra, Aida; Zhu, Hongbin; Gallart-Palau, Xavier; Park, Jung Eun; Ho, Hee Haw; Tam, James P; Sze, Siu Kwan

    2016-03-01

    The ionic detergent sodium deoxycholate (SDC) is compatible with in-solution tryptic digestion and LC-MS/MS-based shotgun proteomics by virtue of being easy to separate from the peptide products via precipitation in acidic buffers. However, it remains unclear whether unique human peptides co-precipitate with SDC during acid treatment of complex biological samples. In this study, we demonstrate for the first time that a large quantity of unique peptides in human blood plasma can be co-precipitated with SDC using an optimized sample preparation method prior to shotgun proteomic analysis. We show that the plasma peptides co-precipitated with SDC can be successfully recovered using a sequential re-solubilization and precipitation procedure, and that this approach is particularly efficient at the extraction of long peptides. Recovery of peptides from the SDC pellet dramatically increased overall proteome coverage (>60 %), thereby improving the identification of low-abundance proteins and enhancing the identification of protein components of membrane-bound organelles. In addition, when we analyzed the physiochemical properties of the co-precipitated peptides, we observed that SDC-based sample preparation improved the identification of mildly hydrophilic/hydrophobic proteins that would otherwise be lost upon discarding the pellet. These data demonstrate that the optimized SDC protocol is superior to sodium dodecyl sulfate (SDS)/urea treatment for identifying plasma biomarkers by shotgun proteomics. PMID:26804737

  5. Behavior of arsenic impurity at antimony electric precipitation

    International Nuclear Information System (INIS)

    In the paper the arsenic impurity electrochemical behavior and it purification from antimony by electric precipitation out of fluoride solutions was studied. For this the arsenic sample with mass 0.003-0.006 g has been irradiated at the WWR-SM nuclear reactor during 3-5 hour in the thermal neutron flux 1013 n/cm2 s, after 24 h keeping the sample has being dissolved in the concentrated nitric acid, and then it has been evaporated several times with distillation water addition up to wet precipitation state. It is shown, that arsenic impurity behavior character in the antimony electric precipitation out to fluoride electrolyte depends on the electrolyte content, electrolysis conditions, arsenic valency state in arsenic impurity existence in the five-valency state its joint electric reduction with antimony is practically not observing. In the case the arsenic being in three-valency state, it joint electric reduction with antimony is taking place. In this time the electrolytic antimony contents arsenic impurities less in dozen time than initial material

  6. 48 CFR 3432.771 - Provision for incremental funding.

    Science.gov (United States)

    2010-10-01

    ... funding. 3432.771 Section 3432.771 Federal Acquisition Regulations System DEPARTMENT OF EDUCATION ACQUISITION REGULATION GENERAL CONTRACTING REQUIREMENTS CONTRACT FINANCING Contract Funding 3432.771 Provision for incremental funding. The contracting officer shall insert the provision in...

  7. Security infrastructure for dynamically provisioned cloud infrastructure services

    NARCIS (Netherlands)

    Y. Demchenko; C. Ngo; C. de Laat; D.R. Lopez; A. Morales; J.A. García-Espín

    2013-01-01

    This chapter discusses conceptual issues, basic requirements and practical suggestions for designing dynamically configured security infrastructure provisioned on demand as part of the cloud-based infrastructure. This chapter describes general use cases for provisioning cloud infrastructure services

  8. The Global Precipitation Measurement (GPM) Project

    Science.gov (United States)

    Azarbarzin, Ardeshir; Carlisle, Candace

    2010-01-01

    The Global Precipitation Measurement (GP!v1) mission is an international cooperative effort to advance the understanding of the physics of the Earth's water and energy cycle. Accurate and timely knowledge of global precipitation is essential for understanding the weather/climate/ecological system, for improving our ability to manage freshwater resources, and for predicting high-impact natural hazard events including floods, droughts, extreme weather events, and landslides. The GPM Core Observatory will be a reference standard to uniformly calibrate data from a constellation of spacecraft with passive microwave sensors. GPM is being developed under a partnership between the United States (US) National Aeronautics and Space Administration (NASA) and the Japanese Aerospace and Exploration Agency (JAXA). NASA's Goddard Space Flight Center (GSFC), in Greenbelt, MD is developing the Core Observatory, two GPM Microwave Imager (GMI) instruments, Ground Validation System and Precipitation Processing System for the GPM mission. JAXA will provide a Dual-frequency Precipitation Radar (DPR) for installation on the Core satellite and launch services for the Core Observatory. The second GMI instrument will be flown on a partner-provided spacecraft. Other US agencies and international partners contribute to the GPM mission by providing precipitation measurements obtained from their own spacecraft and/or providing ground-based precipitation measurements to support ground validation activities. The Precipitation Processing System will provide standard data products for the mission.

  9. The stochastic single node service provision problem

    OpenAIRE

    Dye, S.; Stougie, Leen; Tomasgard, A.

    1999-01-01

    The service provision problem described in this paper comes from an application of distributed processing in telecommunications networks. The objective is to maximize a service provider's profit from offering computational based services to customers. The service provider has limited capacity and must choose from a set of software applications those he would like to offer. This can be done dynamically taking into consideration that demand for the different services is uncertain. The problem i...

  10. Precipitation of flaky moolooite and its thermal decomposition

    Institute of Scientific and Technical Information of China (English)

    Jin-yu Wu; Kai Huang

    2016-01-01

    Moolooite particles with flaky morphology were synthesized by mixing dilute solutions of copper nitrate and sodium oxalate in the presence of citric acid. Solution pH value, citric acid concentration, and stirring were found to have large effect on the shape of the pre-cipitated particles. Under the stirring, the radial area of flaky moolooite particles was enlarged and extended to become a thinner and larger flake. This is ascribed to growth promotion caused by the selective absorption of citric ligands onto a particular crystalline surface of the moolooite particles. Flaky shape of the moolooite particles tended to become spherical and disappeared completely when decomposed under an Ar atmosphere, leading to the formation of large porous aggregated particles composed of many tiny nanosized copper crystals.

  11. Dayside isotropic precipitation of energetic protons

    Directory of Open Access Journals (Sweden)

    V. A. Sergeev

    Full Text Available Recently it has been shown that isotropic precipitation of energetic protons on the nightside is caused by a non-adiabatic effect, namely pitch-angle scattering of protons in curved magnetic field lines of the tail current sheet. Here we address the origin of isotropic proton precipitation on the dayside. Computations of proton scattering regions in the magnetopheric models T87, T89 and T95 reveal two regions which contribute to the isotropic precipitation. The first is the region of weak magnetic field in the outer cusp which provides the 1–2° wide isotropic precipitation on closed field lines in a ~2–3 hour wide MLT sector centered on noon. A second zone is formed by the scattering on the closed field lines which cross the nightside equatorial region near the magnetopause which provides isotropic precipitation starting ≈ 1.5–2 h MLT from noon and which joins smoothly the precipitation coming from the tail current sheet. We also analyzed the isotropic proton precipitation using observations of NOAA low altitude polar spacecraft. We find that isotropic precipitation of >30 to >80 keV protons continues around noon forming the continuous oval-shaped region of isotropic precipitation. Part of this region lies on open field lines in the region of cusp-like or mantle precipitation, its equatorward part is observed on closed field lines. Near noon it extends ~1–2° below the sharp boundary of solar electron fluxes (proxy of the open/closed field line boundary and equatorward of the cusp-like auroral precipitation. The observed energy dispersion of its equatorward boundary (isotropic boundary agrees with model predictions of expected particle scattering in the regions of weak and highly curved magnetic field. We also found some disagreement with model computations. We did not observe the predicted split of the isotropic precipitation region into separate nightside and dayside isotropic zones. Also, the oval-like shape of the isotropic

  12. A New Method for Near Real Time Precipitation Estimates Using a Derived Statistical Relationship between Precipitable Water Vapor and Precipitation

    Science.gov (United States)

    Roman, J.

    2015-12-01

    The IPCC 5th Assessment found that the predicted warming of 1oC would increase the risk of extreme events such as heat waves, droughts, and floods. Weather extremes, like floods, have shown the vulnerability and susceptibility society has to these extreme weather events, through impacts such as disruption of food production, water supply, health, and damage of infrastructure. This paper examines a new way of near-real time forecasting of precipitation. A 10-year statistical climatological relationship was derived between precipitable water vapor (PWV) and precipitation by using the NASA Atmospheric Infrared Sounder daily gridded PWV product and the NASA Tropical Rainfall Measuring Mission daily gridded precipitation total. Forecasting precipitation estimates in real time is dire for flood monitoring and disaster management. Near real time PWV observations from AIRS on Aqua are available through the Goddard Earth Sciences Data and Information Service Center. In addition, PWV observations are available through direct broadcast from the NASA Suomi-NPP ATMS/CrIS instrument, the operational follow on to AIRS. The derived climatological relationship can be applied to create precipitation estimates in near real time by utilizing the direct broadcasting capabilities currently available in the CONUS region. The application of this relationship will be characterized through case-studies by using near real-time NASA AIRS Science Team v6 PWV products and ground-based SuomiNet GPS to estimate the current precipitation potential; the max amount of precipitation that can occur based on the moisture availability. Furthermore, the potential contribution of using the direct broadcasting of the NUCAPS ATMS/CrIS PWV products will be demonstrated. The analysis will highlight the advantages of applying this relationship in near-real time for flash flood monitoring and risk management. Relevance to the NWS River Forecast Centers will be discussed.

  13. Chemical characteristics of precipitation at Nanping Mangdang Mountain in eastern China during spring

    Institute of Scientific and Technical Information of China (English)

    YanliCheng; Ying Liu; Mingqun Huo; Qian Sun; Huixiang Wang; Zhongming Chen; Yuhua Bai

    2011-01-01

    To study the characteristics of precipitation in eastern China,an automatic sampler was used to collect rainwater samples from 19 precipitation events at Mangdang Mountain,Nanping City,Fujiang Province,in the spring of 2009.We used ion chromatography to analyze the ionic components and concentrations,and inductively coupled plasma mass spectrometry (ICP-MS) to analyze element compositions and contents.The results demonstrated remarkable acidic characteristics:in more than 80% of precipitation events the pH was less than 5.6,with an average of 4.81.Mass concentration results showed SO42- was the main anionic component (36.2%of the total anion mass),while NH4+ was the main cationic component (47.7% of the total cation mass) and main ion for acidity neutralization in the rainwater.Organic acid content accounted for 30.9% of total anion mass.The main trace metals were Ca,K,and Na.The SO42-/NO3- ratio was 1.4,indicating that precipitation in this region was influenced by complex air pollution - the product of individual coal-burning combined with vehicle exhaust pollution.Correlation analysis of the chemical composition of the precipitation indicated that acidity in this region was determined by a combination of all acidic and neutralization ions rather than any single ion component.The results also showed that Na+ and C1- contributions were mainly by seawater; Mg2+ by seawater and crustal materials;the NH4+,K+,Ca2+,NO3- and SO42- by anthropogenic sources; the trace metals were from the Earth's crust; and organic acids were potentially from combustion of biomass.

  14. 7 CFR 457.157 - Plum crop insurance provisions.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Plum crop insurance provisions. 457.157 Section 457... CORPORATION, DEPARTMENT OF AGRICULTURE COMMON CROP INSURANCE REGULATIONS § 457.157 Plum crop insurance provisions. The Plum Crop Insurance Provisions for the 2001 and succeeding crop years are as follows:...

  15. 7 CFR 457.116 - Sugarcane crop insurance provisions.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Sugarcane crop insurance provisions. 457.116 Section... CORPORATION, DEPARTMENT OF AGRICULTURE COMMON CROP INSURANCE REGULATIONS § 457.116 Sugarcane crop insurance provisions. The Sugarcane Crop Insurance Provisions for the 2004 and succeeding crop years are as...

  16. 7 CFR 457.153 - Peach crop insurance provisions.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Peach crop insurance provisions. 457.153 Section 457... CORPORATION, DEPARTMENT OF AGRICULTURE COMMON CROP INSURANCE REGULATIONS § 457.153 Peach crop insurance provisions. The Peach Crop Insurance Provisions for the 2001 and succeeding crop years are as follows:...

  17. 24 CFR 5.324 - Implementation of lease provisions.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Implementation of lease provisions... With Disabilities General Requirements § 5.324 Implementation of lease provisions. The lease for each... which this subpart C is implemented shall contain the lease provisions described in § 5.321 and,...

  18. 30 CFR 934.13 - State program provisions set aside.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false State program provisions set aside. 934.13... State program provisions set aside. North Dakota regulation NDAC 69-05.2-27-01 is inconsistent with Federal provisions for permitting and bonding of research projects and is set aside under the...

  19. 5 CFR 317.801 - Retention of SES provisions.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Retention of SES provisions. 317.801... EMPLOYMENT IN THE SENIOR EXECUTIVE SERVICE Retention of SES Provisions § 317.801 Retention of SES provisions. (a) Coverage. This subpart applies to— (1) A career appointee in the SES appointed at any time by...

  20. 7 CFR 457.158 - Apple crop insurance provisions.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Apple crop insurance provisions. 457.158 Section 457... CORPORATION, DEPARTMENT OF AGRICULTURE COMMON CROP INSURANCE REGULATIONS § 457.158 Apple crop insurance provisions. The Apple Crop Insurance Provisions for the 2005 and succeeding crop years are as follows:...

  1. 48 CFR 25.1103 - Other provisions and clauses.

    Science.gov (United States)

    2010-10-01

    ... SOCIOECONOMIC PROGRAMS FOREIGN ACQUISITION Solicitation Provisions and Contract Clauses 25.1103 Other provisions..., in solicitations and contracts if anticipating translation into another language. (c) Foreign... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Other provisions...

  2. Precipitation Recycling and the Vertical Distribution of Local and Remote Sources of Water for Precipitation

    Science.gov (United States)

    Bosilovich, Michael G.; Atlas, Robert (Technical Monitor)

    2002-01-01

    Precipitation recycling is defined as the amount of water that evaporates from a region that precipitates within the same region. This is also interpreted as the local source of water for precipitation. In this study, the local and remote sources of water for precipitation have been diagnosed through the use of passive constituent tracers that represent regional evaporative sources along with their transport and precipitation. We will discuss the differences between this method and the simpler bulk diagnostic approach to precipitation recycling. A summer seasonal simulation has been analyzed for the regional sources of the United States Great Plains precipitation. While the tropical Atlantic Ocean (including the Gulf of Mexico) and the local continental sources of precipitation are most dominant, the vertically integrated column of water contains substantial water content originating from the Northern Pacific Ocean, which is not precipitated. The vertical profiles of regional water sources indicate that local Great Plains source of water dominates the lower troposphere, predominantly in the PBL. However, the Pacific Ocean source is dominant over a large portion of the middle to upper troposphere. The influence of the tropical Atlantic Ocean is reasonably uniform throughout the column. While the results are not unexpected given the formulation of the model's convective parameterization, the analysis provides a quantitative assessment of the impact of local evaporation on the occurrence of convective precipitation in the GCM. Further, these results suggest that local source of water is not well mixed throughout the vertical column.

  3. Atom probe study of vanadium interphase precipitates and randomly distributed vanadium precipitates in ferrite.

    Science.gov (United States)

    Nöhrer, M; Zamberger, S; Primig, S; Leitner, H

    2013-01-01

    Atom probe tomography and transmission electron microscopy were used to examine the precipitation reaction in the austenite and ferrite phases in vanadium micro-alloyed steel after a thermo-mechanical process. It was observed that only in the ferrite phase precipitates could be found, whereupon two different types were detected. Thus, the aim was to reveal the difference between these two types. The first type was randomly distributed precipitates from V supersaturated ferrite and the second type V interphase precipitates. Not only the arrangement of the particles was different also the chemical composition. The randomly distributed precipitates consisted of V, C and N in contrast to that the interphase precipitates showed a composition of V, C and Mn. Furthermore the randomly distributed precipitates had maximum size of 20 nm and the interphase precipitates a maximum size of 15 nm. It was assumed that the reason for these differences is caused by the site in which they were formed. The randomly distributed precipitates were formed in a matrix consisting mainly of 0.05 at% C, 0.68 at% Si, 0.03 at% N, 0.145 at% V and 1.51 at% Mn. The interphase precipitates were formed in a region with a much higher C, Mn and V content. PMID:24041583

  4. Analysis of Endoscopic Pancreatic Function Test (ePFT-Collected Pancreatic Fluid Proteins Precipitated Via Ultracentrifugation

    Directory of Open Access Journals (Sweden)

    Joao A Paulo

    2013-03-01

    Full Text Available Context We have shown previously that trichloroacetic acid precipitation is an effective method of protein extraction frompancreatic fluid for downstream biomarker discovery, compared to other common extraction methods tested. Objective We aim to assess the utility of ultracentrifugation as an alternative method of protein extraction from pancreatic fluid. Design Proteins extracted from trichloroacetic acid- and ultracentrifugation-precipitated pancreatic fluid were identified using mass spectrometry techniques (in-gel tryptic digestion followed by liquid chromatography-tandem mass spectrometry; GeLC-MS/MS. Data were analyzed using Proteome Discoverer and Scaffold 3. Setting This is a proteomic analysis experiment of endoscopically collected fluid in an academic center. Patients The study population included adult patients referred to the Center for Pancreatic Disease at Brigham and Women’s Hospital, Boston, MA, USA for the evaluation of abdominal pain and gastrointestinal symptoms. Interventions Secretinstimulated pancreatic fluid was collected as standard of care for the evaluation of abdominal pain and gastrointestinal symptoms. Main outcome measures We compared proteins identified via standard trichloroacetic acid precipitation and this alternative ultracentrifugation strategy. Results A subset of pancreatic fluid proteins was identified via the ultracentrifugation method. Of these proteins, similar numbers were obtained from fully tryptic or semi-tryptic database searching. Proteins identified in the ultracentrifugation-precipitated samples included previously identified biomarker candidates of chronic pancreatitis. Conclusions This alternative ultracentrifugation strategy requires less time and fewer handling procedures than standard trichloroacetic acid precipitation, at the expense of higher sample volume. As such, this method is well suited for targeted assays (i.e., dot blotting or targeted mass spectrometry if the protein of

  5. Asphaltene precipitates in oil production wells

    DEFF Research Database (Denmark)

    Kleinitz, W,; Andersen, Simon Ivar

    1998-01-01

    At the beginning of production in a southern German oil field, flow blockage was observed during file initial stage of production from the oil wells. The hindrance was caused by the precipitation of asphaltenes in the proximity of the borehole and in the tubings. The precipitates were of solid......, "dry" consistency and resulted in total damage to flow. On the basis of residue samples from the wells, a number of physical and chemical analyses were performed, and the results were compared with those from studies on other asphaltenic precipitates. Among other items, the fraction of aromatic...... compounds in the organic scales from operations definitely differed from the data published in the literature. In order to dissolve the precipitates and thus eliminate the damage, various organic solvents and industrial solvent mixtures were examined. The kinetics of the dissolution process in operational...

  6. Precipitation Reconstruction over Land (PREC/L)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The monthly data set consists files of 3 resolutions of monthly averaged precipitation totals. The global analyses are defined by interpolation of gauge...

  7. U.S. Hourly Precipitation Data Publication

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This publication contains hourly precipitation amounts obtained from recording rain gages located at National Weather Service, Federal Aviation Administration, and...

  8. U.S. Hourly Precipitation Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Hourly Precipitation Data (HPD) is digital data set DSI-3240, archived at the National Climatic Data Center (NCDC). The primary source of data for this file is...

  9. River Forecasting Center Quantitative Precipitation Estimate Archive

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Radar indicated-rain gage verified and corrected hourly precipitation estimate on a corrected ~4km HRAP grid. This archive contains hourly estimates of...

  10. Identifying External Influences on Global Precipitation (Invited)

    Science.gov (United States)

    Marvel, K.; Bonfils, C.

    2013-12-01

    Changes in global (ocean and land) precipitation are among the most important and least well-understood consequences of climate change. Increasing greenhouse gas concentrations are thought to affect the zonal distribution of precipitation through two basic mechanisms. First, increasing temperatures will lead to an intensification of the hydrological cycle ('thermodynamic' changes). Second, changes in atmospheric circulation patterns will lead to poleward displacement of the storm tracks and subtropical dry zones and to a widening of the tropical belt ('dynamic' changes). We demonstrate that both these changes are occurring simultaneously in global precipitation, that this behavior cannot be explained by internal variability alone, and that external anthropogenic influences are responsible for the observed precipitation changes.

  11. NESDIS Blended Total Precipitable Water (TPW) Products

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The blended Total Precipitable Water (TPW) product is derived from multiple sensors/satellites. The Percentage of TPW normal (PCT), or TPW anomaly, shows the...

  12. Precipitation Aggregation and the Local Environment

    Science.gov (United States)

    Smalley, Mark

    The details of large-scale spatial structures of precipitation have only recently become apparent with the advent of high-resolution near-global observations from space-borne radars. As such, the relationships between these structures and the local environment and global climate are just beginning to emerge in the scientific community. Precipitation aggregates on a wide variety of scales, from individual boundary layer instabilities to extra-tropical cyclones. Separate aggregation states have been associated with widely varying precipitation rates and atmospheric states, motivating the inclusion of spatial information in hydrologic and climate models. This work adds to the body of knowledge surrounding large-scale precipitation aggregation and its driving factors by describing and demonstrating a new method of defining the spatial characteristics of precipitation events. The analysis relies on the high sensitivity and high resolution of the CloudSat Cloud Profiling Radar for the identification of precipitation with near-global coverage. The method is based on the dependence of the probability of precipitation on search area, or spatial resolution. Variations in this relationship are caused by variations in the principal characteristics of event spatial patterns: the relative spacing between events, the number density of events, and the overall fraction of precipitating scenes at high resolution. Here, this relationship is modeled by a stretched exponential containing two coefficients, that are shown to depict seasonal general circulation patterns as well as local weather. NASA's Modern-Era Retrospective analysis for Research and Applications is then used to place those spatial characteristics in the context of the local and large-scale environment. At regional scale, precipitation event density during the Amazon wet season is shown to be dependent on zonal wind speed. On a global scale, the relative spacing of shallow oceanic precipitation depends on the

  13. 12 CFR 714.8 - Are the early payment provisions, or interest rate provisions, applicable in leasing arrangements?

    Science.gov (United States)

    2010-01-01

    ... rate provisions, applicable in leasing arrangements? 714.8 Section 714.8 Banks and Banking NATIONAL CREDIT UNION ADMINISTRATION REGULATIONS AFFECTING CREDIT UNIONS LEASING § 714.8 Are the early payment provisions, or interest rate provisions, applicable in leasing arrangements? You are not subject to the...

  14. Scaling behaviors of precipitation over China

    Science.gov (United States)

    Jiang, Lei; Li, Nana; Zhao, Xia

    2015-12-01

    Scaling behaviors in the precipitation time series derived from 1951 to 2009 over China are investigated by detrended fluctuation analysis (DFA) method. The results show that there exists long-term memory for the precipitation time series in some stations, where the values of the scaling exponent α are less than 0.62, implying weak persistence characteristics. The values of scaling exponent in other stations indicate random behaviors. In addition, the scaling exponent α in precipitation records varies from station to station over China. A numerical test is made to verify the significance in DFA exponents by shuffling the data records many times. We think it is significant when the values of scaling exponent before shuffled precipitation records are larger than the interval threshold for 95 % confidence level after shuffling precipitation records many times. By comparison, the daily precipitation records exhibit weak positively long-range correlation in a power law fashion mainly at the stations taking on zonal distributions in south China, upper and middle reaches of the Yellow River, northern part of northeast China. This may be related to the subtropical high. Furthermore, the values of scaling exponent which cannot pass the significance test do not show a clear distribution pattern. It seems that the stations are mainly distributed in coastal areas, southwest China, and southern part of north China. In fact, many complicated factors may affect the scaling behaviors of precipitation such as the system of the east and south Asian monsoon, the interaction between sea and land, and the big landform of the Tibetan Plateau. These results may provide a better prerequisite to long-term predictor of precipitation time series for different regions over China.

  15. Microbially Induced Calcite Precipitation Employing Environmental Isolates

    OpenAIRE

    Gunjo Kim; Heejung Youn

    2016-01-01

    In this study, five microbes were employed to precipitate calcite in cohesionless soils. Four microbes were selected from calcite-precipitating microbes isolated from calcareous sand and limestone cave soils, with Sporosarcina pasteurii ATCC 11859 (standard strain) used as a control. Urease activities of the four microbes were higher than that of S. pasteurii. The microbes and urea–CaCl2 medium were injected at least four times into cohesionless soils of two different relative densities (60% ...

  16. Thunderstorms and thunderstorm precipitations in southern Poland

    Directory of Open Access Journals (Sweden)

    Bielec-Bąkowska Zuzanna

    2014-09-01

    Full Text Available This paper addresses spatial and temporal variability in the occurrence of thunderstorms and related precipitation in southern Poland between 1951 and 2010. The analysis was based on thunderstorm observations and daily precipitation totals (broken down into the few ranges from 15 meteorological stations. It was found that precipitation accompanied an overwhelming majority of thunderstorms. The most frequent range of thunderstorm precipitation totals was 0.1–10.0 mm which accounted for 60% of all values while precipitation higher than 20.0 mm accounted only for ca. 8%. During the study period, long-term change in the number of days with thunderstorm precipitation within a certain range displayed no clear-cut trends. Exceptions included: 1 an increase in the number of days with thunderstorm precipitation in the lowest range of totals (0.1–10.0 mm at Katowice, Tarnów, Rzeszów and Lesko and decrease at Mt. Kasprowy Wierch, 2 an increase in the range 10.1–20.0 mm at Zakopane and 20.1–30.0 mm at Opole, 3 a decrease of the top range (more than 30.0 mm at Mt. Śnieżka. It was found that the heaviest thunderstorm precipitation events, i.e. totalling more than 30 mm, and those events that covered all or most of the study area, occurred at the time of air advection from the southern or eastern sectors and a passage of atmospheric fronts.

  17. Kinetics of niobium carbide precipitation in ferrite

    International Nuclear Information System (INIS)

    The aim of this study is to develop a NbC precipitation modelling in ferrite. This theoretical study is motivated by the fact it considers a ternary system and focus on the concurrence of two different diffusion mechanisms. An experimental study with TEP, SANS and Vickers micro-hardening measurements allows a description of the NbC precipitation kinetics. The mean radius of the precipitates is characterized by TEM observations. To focus on the nucleation stage, we use the Tomographic Atom Probe that analyses, at an atomistic scale, the position of the solute atoms in the matrix. A first model based on the classical nucleation theory and the diffusion-limited growth describes the precipitation of spherical precipitates. To solve the set of equations, we use a numerical algorithm that furnishes an evaluation of the precipitated fraction, the mean radius and the whole size distribution of the particles. The parameters that are the interface energy, the solubility product and the diffusion coefficients are fitted with the data available in the literature and our experimental results. It allows a satisfactory agreement as regards to the simplicity of the model. Monte Carlo simulations are used to describe the evolution of a ternary alloy Fe-Nb-C on a cubic centred rigid lattice with vacancy and interstitial mechanisms. This is realized with an atomistic description of the atoms jumps and their related frequencies. The model parameters are fitted with phase diagrams and diffusion coefficients. For the sake of simplicity, we consider that the precipitation of NbC is totally coherent and we neglect any elastic strain effect. We can observe different kinetic paths: for low supersaturations, we find an expected precipitation of NbC but for higher supersaturations, the very fast diffusivity of carbon atoms conducts to the nucleation of iron carbide particles. We establish that the occurrence of this second phenomenon depends on the vacancy arrival kinetics and can be related

  18. Discontinuous precipitation in copper base alloys

    Indian Academy of Sciences (India)

    K T Kashyap

    2009-08-01

    Discontinuous precipitation (DP) is associated with grain boundary migration in the wake of which alternate plates of the precipitate and the depleted matrix form. Some copper base alloys show DP while others do not. In this paper the misfit strain parameter, , has been calculated and predicted that if 100 > ± 0.1, DP is observed. This criterion points to diffusional coherency strain theory to be the operative mechanism for DP.

  19. In-Drift Precipitates/Salts Model

    International Nuclear Information System (INIS)

    This report documents the development and validation of the in-drift precipitates/salts (IDPS) model. The IDPS model is a geochemical model designed to predict the postclosure effects of evaporation and deliquescence on the chemical composition of water within the Engineered Barrier System (EBS) in support of the Total System Performance Assessment for the License Application (TSPA-LA). Application of the model in support of TSPA-LA is documented in ''Engineered Barrier System: Physical and Chemical Environment Model'' (BSC 2004 [DIRS 169860]). Technical Work Plan for: Near-Field Environment and Transport In-Drift Geochemistry Model Report Integration (BSC 2004 [DIRS 171156]) is the technical work plan (TWP) for this report. It called for a revision of the previous version of the report (BSC 2004 [DIRS 167734]) to achieve greater transparency, readability, data traceability, and report integration. The intended use of the IDPS model is to estimate and tabulate, within an appropriate level of confidence, the effects of evaporation, deliquescence, and potential environmental conditions on the pH, ionic strength, and chemical compositions of water and minerals on the drip shield or other location within the drift during the postclosure period. Specifically, the intended use is as follows: (1) To estimate, within an appropriate level of confidence, the effects of evaporation and deliquescence on the presence and composition of water occurring within the repository during the postclosure period (i.e., effects on pH, ionic strength, deliquescence relative humidity, total concentrations of dissolved components in the system Na-K-H-Mg-Ca-Al-Cl-F-NO3-SO4-Br-CO3-SiO2-CO2-O2-H2O, and concentrations of the following aqueous species that potentially affect acid neutralizing capacity: HCO3-, CO32-, OH-, H+, HSO4-, Ca2+, Mg2+, CaHCO3+, MgHCO3+, HSiO3-, and MgOH+); (2) To estimate, within an appropriate level of confidence, mineral precipitation resulting from the evaporation of

  20. In-Drift Precipitates/Salts Model

    Energy Technology Data Exchange (ETDEWEB)

    P. Mariner

    2004-11-09

    This report documents the development and validation of the in-drift precipitates/salts (IDPS) model. The IDPS model is a geochemical model designed to predict the postclosure effects of evaporation and deliquescence on the chemical composition of water within the Engineered Barrier System (EBS) in support of the Total System Performance Assessment for the License Application (TSPA-LA). Application of the model in support of TSPA-LA is documented in ''Engineered Barrier System: Physical and Chemical Environment Model'' (BSC 2004 [DIRS 169860]). Technical Work Plan for: Near-Field Environment and Transport In-Drift Geochemistry Model Report Integration (BSC 2004 [DIRS 171156]) is the technical work plan (TWP) for this report. It called for a revision of the previous version of the report (BSC 2004 [DIRS 167734]) to achieve greater transparency, readability, data traceability, and report integration. The intended use of the IDPS model is to estimate and tabulate, within an appropriate level of confidence, the effects of evaporation, deliquescence, and potential environmental conditions on the pH, ionic strength, and chemical compositions of water and minerals on the drip shield or other location within the drift during the postclosure period. Specifically, the intended use is as follows: (1) To estimate, within an appropriate level of confidence, the effects of evaporation and deliquescence on the presence and composition of water occurring within the repository during the postclosure period (i.e., effects on pH, ionic strength, deliquescence relative humidity, total concentrations of dissolved components in the system Na-K-H-Mg-Ca-Al-Cl-F-NO{sub 3}-SO{sub 4}-Br-CO{sub 3}-SiO{sub 2}-CO{sub 2}-O{sub 2}-H{sub 2}O, and concentrations of the following aqueous species that potentially affect acid neutralizing capacity: HCO{sub 3}{sup -}, CO{sub 3}{sup 2-}, OH{sup -}, H{sup +}, HSO{sub 4}{sup -}, Ca{sup 2+}, Mg{sup 2+}, CaHCO{sub 3}{sup +}, MgHCO{sub 3

  1. Enhanced precipitation variability decreases grass- and increases shrub-productivity

    Science.gov (United States)

    Although projections of precipitation change indicate increases in variability, most studies of impacts of climate change on ecosystems focused on effects of changes in amount of precipitation, overlooking precipitation variability effects, especially at the interannual scale. Here, we present resul...

  2. Climate Prediction Center (CPC) Global Precipitation Time Series

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The global precipitation time series provides time series charts showing observations of daily precipitation as well as accumulated precipitation compared to normal...

  3. Impact of GCM boundary forcing on regional climate modeling of West African summer monsoon precipitation and circulation features

    Science.gov (United States)

    Kebe, Ibourahima; Sylla, Mouhamadou Bamba; Omotosho, Jerome Adebayo; Nikiema, Pinghouinde Michel; Gibba, Peter; Giorgi, Filippo

    2016-05-01

    In this study, the latest version of the International Centre for Theoretical Physics Regional Climate Model (RegCM4) driven by three CMIP5 Global Climate Models (GCMs) is used at 25 km grid spacing over West Africa to investigate the impact of lateral boundary forcings on the simulation of monsoon precipitation and its relationship with regional circulation features. We find that the RegCM4 experiments along with their multimodel ensemble generally reproduce the location of the main precipitation characteristics over the region and improve upon the corresponding driving GCMs. However, the provision of different forcing boundary conditions leads to substantially different precipitation magnitudes and spatial patterns. For instance, while RegCM4 nested within GFDL-ESM-2M and HadGEM2-ES exhibits some underestimations of precipitation and an excessively narrow Intertropical Convergence Zone, the MPI-ESM-MR driven run produces precipitation spatial distribution and magnitudes more similar to observations. Such a superior performance originates from a much better simulation of the interactions between baroclinicity, temperature gradient and African Easterly Jet along with an improved connection between the Isentropic Potential Vorticity, its gradient and the African Easterly Waves dynamics. We conclude that a good performing GCM in terms of monsoon dynamical features (in this case MPI-ESM-MR) is needed to drive RCMs in order to achieve a better representation of the West Africa summer monsoon precipitation.

  4. Precipitation in a lead calcium tin anode

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Gonzalez, Francisco A., E-mail: fco.aurelio@inbox.com [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon (Mexico); Centro de Innovacion, Investigacion y Desarrollo en Ingenieria y Tecnologia, Universidad Autonoma de Nuevo Leon (Mexico); Camurri, Carlos G., E-mail: ccamurri@udec.cl [Departamento de Ingenieria de Materiales, Universidad de Concepcion (Chile); Carrasco, Claudia A., E-mail: ccarrascoc@udec.cl [Departamento de Ingenieria de Materiales, Universidad de Concepcion (Chile); Colas, Rafael, E-mail: rafael.colas@uanl.edu.mx [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon (Mexico); Centro de Innovacion, Investigacion y Desarrollo en Ingenieria y Tecnologia, Universidad Autonoma de Nuevo Leon (Mexico)

    2012-02-15

    Samples from a hot rolled sheet of a tin and calcium bearing lead alloy were solution heat treated at 300 Degree-Sign C and cooled down to room temperature at different rates; these samples were left at room temperature to study natural precipitation of CaSn{sub 3} particles. The samples were aged for 45 days before analysing their microstructure, which was carried out in a scanning electron microscope using secondary and backscattered electron detectors. Selected X-ray spectra analyses were conducted to verify the nature of the precipitates. Images were taken at different magnifications in both modes of observation to locate the precipitates and record their position within the images and calculate the distance between them. Differential scanning calorimeter analyses were conducted on selected samples. It was found that the mechanical properties of the material correlate with the minimum average distance between precipitates, which is related to the average cooling rate from solution heat treatment. - Highlights: Black-Right-Pointing-Pointer The distance between precipitates in a lead alloy is recorded. Black-Right-Pointing-Pointer The relationship between the distance and the cooling rate is established. Black-Right-Pointing-Pointer It is found that the strengthening of the alloy depends on the distance between precipitates.

  5. What weather features produce extreme precipitation globally?

    Science.gov (United States)

    Dowdy, Andrew; Catto, Jennifer

    2016-04-01

    Extreme precipitation (defined as above the 99th percentile) has been examined previously in relation to a number of different weather events. Such events include cyclones, fronts, and thunderstorms. However, previous studies have not examined various combinations of these weather events, which highlights the potential for an improved understanding of what causes extreme precipitation. Here we make use of objective cyclone and front identification methods and a global dataset of lightning strikes, to examine different combinations of cyclone, front and thunderstorm events to provide a comprehensive climatological examination of observed extreme precipitation events throughout the world. This method allows a number of novel concepts to be explored, with results showing that the highest risk of extreme precipitation occurs for a type of "triple storm" event characterised by the simultaneous occurrence of a cyclone, front and thunderstorm. The physical properties of the various different combinations of weather systems are examined in relation to the occurrence of extreme precipitation. The results presented here are intended to lead to better preparedness for the impacts of extreme precipitation throughout the world including in relation to disaster risk reduction.

  6. Precipitation response to regional radiative forcing

    Directory of Open Access Journals (Sweden)

    D. T. Shindell

    2012-02-01

    Full Text Available Precipitation shifts can have large impacts on human society and ecosystems. Many aspects of how inhomogeneous radiative forcings influence precipitation remain unclear, however. Here we investigate regional precipitation responses to various forcings imposed in different latitude bands in a climate model. We find that several regions show strong, significant responses to most forcings, but the magnitude and even the sign depends upon the forcing location and type. Aerosol and ozone forcings typically induce larger responses than equivalent carbon dioxide (CO2 forcing, and the influence of remote forcings often outweighs that of local forcings. Consistent with this, ozone and especially aerosols contribute greatly to precipitation changes over the Sahel and South and East Asia in historical simulations, and inclusion of aerosols greatly increases the agreement with observed trends in these areas, which cannot be attributed to either greenhouse gases or natural forcings. Estimates of precipitation responses derived from multiplying our Regional Precipitation Potential (RPP; the response per unit forcing relationships by historical forcings typically capture the actual response in full transient climate simulations fairly well, suggesting that these relationships may provide useful metrics. The strong sensitivity to aerosol and ozone forcing suggests that although some air quality improvements may unmask greenhouse gas-induced changes in temperature, they have large benefits for reducing regional disruption of the hydrologic cycle.

  7. Precipitation response to regional radiative forcing

    Directory of Open Access Journals (Sweden)

    D. T. Shindell

    2012-08-01

    Full Text Available Precipitation shifts can have large impacts on human society and ecosystems. Many aspects of how inhomogeneous radiative forcings influence precipitation remain unclear, however. Here we investigate regional precipitation responses to various forcings imposed in different latitude bands in a climate model. We find that several regions show strong, significant responses to most forcings, but that the magnitude and even the sign depends upon the forcing location and type. Aerosol and ozone forcings typically induce larger responses than equivalent carbon dioxide (CO2 forcing, and the influence of remote forcings often outweighs that of local forcings. Consistent with this, ozone and especially aerosols contribute greatly to precipitation changes over the Sahel and South and East Asia in historical simulations, and inclusion of aerosols greatly increases the agreement with observed trends in these areas, which cannot be attributed to either greenhouse gases or natural forcings. Estimates of precipitation responses derived from multiplying our Regional Precipitation Potentials (RPP; the response per unit forcing relationships by historical forcings typically capture the actual response in full transient climate simulations fairly well, suggesting that these relationships may provide useful metrics. The strong sensitivity to aerosol and ozone forcing suggests that although some air quality improvements may unmask greenhouse gas-induced warming, they have large benefits for reducing regional disruption of the hydrologic cycle.

  8. Spatial dependences among precipitation maxima over Belgium

    Science.gov (United States)

    Vannitsem, S.; Naveau, P.

    2007-09-01

    For a wide range of applications in hydrology, the probability distribution of precipitation maxima represents a fundamental quantity to build dykes, propose flood planning policies, or more generally, to mitigate the impact of precipitation extremes. Classical Extreme Value Theory (EVT) has been applied in this context by usually assuming that precipitation maxima can be considered as Independent and Identically Distributed (IID) events, which approximately follow a Generalized Extreme Value distribution (GEV) at each recording site. In practice, weather stations records can not be considered as independent in space. Assessing the spatial dependences among precipitation maxima provided by two Belgium measurement networks is the main goal of this work. The pairwise dependences are estimated by a variogram of order one, also called madogram, that is specially tailored to be in compliance with spatial EVT and to capture EVT bivariate structures. Our analysis of Belgium precipitation maxima indicates that the degree of dependence varies greatly according to three factors: the distance between two stations, the season (summer or winter) and the precipitation accumulation duration (hourly, daily, monthly, etc.). Increasing the duration (from one hour to 20 days) strengthens the spatial dependence. The full independence is reached after about 50 km (100 km) for summer (winter) for a duration of one hour, while for long durations only after a few hundred kilometers. In addition this dependence is always larger in winter than in summer whatever is the duration. An explanation of these properties in terms of the dynamical processes dominating during the two seasons is advanced.

  9. Precipitation from Space: Advancing Earth System Science

    Science.gov (United States)

    Kucera, Paul A.; Ebert, Elizabeth E.; Turk, F. Joseph; Levizzani, Vicenzo; Kirschbaum, Dalia; Tapiador, Francisco J.; Loew, Alexander; Borsche, M.

    2012-01-01

    Of the three primary sources of spatially contiguous precipitation observations (surface networks, ground-based radar, and satellite-based radar/radiometers), only the last is a viable source over ocean and much of the Earth's land. As recently as 15 years ago, users needing quantitative detail of precipitation on anything under a monthly time scale relied upon products derived from geostationary satellite thermal infrared (IR) indices. The Special Sensor Microwave Imager (SSMI) passive microwave (PMW) imagers originated in 1987 and continue today with the SSMI sounder (SSMIS) sensor. The fortunate longevity of the joint National Aeronautics and Space Administration (NASA) and Japan Aerospace Exploration Agency (JAXA) Tropical Rainfall Measuring Mission (TRMM) is providing the environmental science community a nearly unbroken data record (as of April 2012, over 14 years) of tropical and sub-tropical precipitation processes. TRMM was originally conceived in the mid-1980s as a climate mission with relatively modest goals, including monthly averaged precipitation. TRMM data were quickly exploited for model data assimilation and, beginning in 1999 with the availability of near real time data, for tropical cyclone warnings. To overcome the intermittently spaced revisit from these and other low Earth-orbiting satellites, many methods to merge PMW-based precipitation data and geostationary satellite observations have been developed, such as the TRMM Multisatellite Precipitation Product and the Climate Prediction Center (CPC) morphing method (CMORPH. The purpose of this article is not to provide a survey or assessment of these and other satellite-based precipitation datasets, which are well summarized in several recent articles. Rather, the intent is to demonstrate how the availability and continuity of satellite-based precipitation data records is transforming the ways that scientific and societal issues related to precipitation are addressed, in ways that would not be

  10. Ecohydrology frameworks for green infrastructure design and ecosystem service provision

    Science.gov (United States)

    Pavao-Zuckerman, M.; Knerl, A.; Barron-Gafford, G.

    2014-12-01

    Urbanization is a dominant form of landscape change that affects the structure and function of ecosystems and alters control points in biogeochemical and hydrologic cycles. Green infrastructure (GI) has been proposed as a solution to many urban environmental challenges and may be a way to manage biogeochemical control points. Despite this promise, there has been relatively limited empirical focus to evaluate the efficacy of GI, relationships between design and function, and the ability of GI to provide ecosystem services in cities. This work has been driven by goals of adapting GI approaches to dryland cities and to harvest rain and storm water for providing ecosystem services related to storm water management and urban heat island mitigation, as well as other co-benefits. We will present a modification of ecohydrologic theory for guiding the design and function of green infrastructure for dryland systems that highlights how GI functions in context of Trigger - Transfer - Reserve - Pulse (TTRP) dynamic framework. Here we also apply this TTRP framework to observations of established street-scape green infrastructure in Tucson, AZ, and an experimental installation of green infrastructure basins on the campus of Biosphere 2 (Oracle, AZ) where we have been measuring plant performance and soil biogeochemical functions. We found variable sensitivity of microbial activity, soil respiration, N-mineralization, photosynthesis and respiration that was mediated both by elements of basin design (soil texture and composition, choice of surface mulches) and antecedent precipitation inputs and soil moisture conditions. The adapted TTRP framework and field studies suggest that there are strong connections between design and function that have implications for stormwater management and ecosystem service provision in dryland cities.

  11. [Characteristics of precipitation pH and conductivity at Mt. Huang].

    Science.gov (United States)

    Shi, Chun-e; Deng, Xue-liang; Wu, Bi-wen; Hong, Jie; Zhang, Su; Yang, Yuan-jian

    2013-05-01

    To understand the general characteristics of pH distribution and pollution in precipitation at Mt. Huang, statistical analyses were conducted for the routine measurements of pH and conductivity (K) at Mt. Huang during 2006-2011. The results showed that: (1) Over the period of study, the annual volume weighted mean (VWM) precipitation pH varied from 4.81 to 5.57, with precipitation acidity strengthening before 2009 and weakening thereafter. The precipitation acidity showed evident seasonal variations, with the VWM pH lowest in winter (4.78), and highest in summer (5.33). The occurrence frequency of acid rain was 46% , accounting for 45% of total rainfalls and with the most frequent pH falling into weak acid to neutral rain. (2) The annual VWM K varied from 16.91 to 27.84 microS x cm(-1), with no evident trend. As for ions pollution, the precipitation was relatively clean at Mt. Huang, with the most frequent K range being below 15 microS x cm(-1), followed by 15-25 microS x cm(-1). From February 2010 to December 2011, precipitation samples were collected on daily basis for ions analysis, as well as pH and K measurement in lab. Detailed comparisons were conducted between the two sets of pH and K, one set from field measurement and the other from lab measurement. The results indicated: (1) The lab measured pH (K) was highly correlated with the field pH (K); however, the lab pH tended to move towards neutral comparing with the corresponding field pH, and the shift range was closely correlated with the field pH and rainfall. The shift range of K from field to lab was highly correlated with the total ion concentration of precipitation. The field K showed evident negative correlation with the field pH with a correlation coefficient of -0.51. (2) When sampling with nylon-polyethylene bags, the statistics showed smaller bias between two sets of pH, with higher correlation coefficient between two sets of K. Furthermore, the lab K also showed evident negative correlation with

  12. Global Precipitation Measurement (GPM) Mission: Precipitation Processing System (PPS) GPM Mission Gridded Text Products Provide Surface Precipitation Retrievals

    Science.gov (United States)

    Stocker, Erich Franz; Kelley, O.; Kummerow, C.; Huffman, G.; Olson, W.; Kwiatkowski, J.

    2015-01-01

    In February 2015, the Global Precipitation Measurement (GPM) mission core satellite will complete its first year in space. The core satellite carries a conically scanning microwave imager called the GPM Microwave Imager (GMI), which also has 166 GHz and 183 GHz frequency channels. The GPM core satellite also carries a dual frequency radar (DPR) which operates at Ku frequency, similar to the Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar, and a new Ka frequency. The precipitation processing system (PPS) is producing swath-based instantaneous precipitation retrievals from GMI, both radars including a dual-frequency product, and a combined GMIDPR precipitation retrieval. These level 2 products are written in the HDF5 format and have many additional parameters beyond surface precipitation that are organized into appropriate groups. While these retrieval algorithms were developed prior to launch and are not optimal, these algorithms are producing very creditable retrievals. It is appropriate for a wide group of users to have access to the GPM retrievals. However, for researchers requiring only surface precipitation, these L2 swath products can appear to be very intimidating and they certainly do contain many more variables than the average researcher needs. Some researchers desire only surface retrievals stored in a simple easily accessible format. In response, PPS has begun to produce gridded text based products that contain just the most widely used variables for each instrument (surface rainfall rate, fraction liquid, fraction convective) in a single line for each grid box that contains one or more observations.This paper will describe the gridded data products that are being produced and provide an overview of their content. Currently two types of gridded products are being produced: (1) surface precipitation retrievals from the core satellite instruments GMI, DPR, and combined GMIDPR (2) surface precipitation retrievals for the partner constellation

  13. Understanding Oceanic Heavy Precipitation Using Scatterometer, Satellite Precipitation, and Reanalysis Products

    Science.gov (United States)

    Garg, Piyush; Nesbitt, Stephen W.; Lang, Timothy J.; Chronis, Themis

    2016-01-01

    The primary aim of this study is to understand the heavy precipitation events over Oceanic regions using vector wind retrievals from space based scatterometers in combination with precipitation products from satellite and model reanalysis products. Heavy precipitation over oceans is a less understood phenomenon and this study tries to fill in the gaps which may lead us to a better understanding of heavy precipitation over oceans. Various phenomenon may lead to intense precipitation viz. MJO (Madden-Julian Oscillation), Extratropical cyclones, MCSs (Mesoscale Convective Systems), that occur inside or outside the tropics and if we can decipher the physical mechanisms behind occurrence of heavy precipitation, then it may lead us to a better understanding of such events which further may help us in building more robust weather and climate models. During a heavy precipitation event, scatterometer wind observations may lead us to understand the governing dynamics behind that event near the surface. We hypothesize that scatterometer winds can observe significant changes in the near-surface circulation and that there are global relationships among these quantities. To the degree to which this hypothesis fails, we will learn about the regional behavior of heavy precipitation-producing systems over the ocean. We use a "precipitation feature" (PF) approach to enable statistical analysis of a large database of raining features.

  14. Separation and purification of uranium product from thorium in thorex process by precipitation technique

    International Nuclear Information System (INIS)

    A sequential precipitation technique is reported for the separation of uranium and thorium present in the uranium product stream of a single cycle 5 per cent TBP Thorex Process. It involves the precipitation of thorium as oxalate in 1M HNO3 medium at 60-70degC and after filtration, precipitation of uranium as ammonium diuranate at 80-90degC from the oxalate supernatant. This technique has several advantages over the ion-exchange process normally used for treating these products. In order to meet the varying feed conditions, this method has been tested for feeds containing 10 g/1 uranium and 1-50 g/1 thorium in 1-6M HNO3. Various parameters like feed acidities, uranium and thorium concentrations, excess oxalic acid concentrations in the oxalate supernatant, precipitation temperatures, precipitate wash volumes etc. have been optimised to obtain more than 99 per cent recovery of thorium and uranium as their oxides with less than 50 ppm uranium losses to ammonium diuranate filtrate. The distribution patterns of different fission products and stainless steel corrosion products during various steps of this procedure have also been studied. For simulating the actual Thorex plant scale operation, experiments have been conducted with 25g and 100g lots of uranium per batch. (author). 6 tabs., 8 figs., 22 refs

  15. Meteorological and chemical factors controlling the composition of precipitation in eastern North America

    International Nuclear Information System (INIS)

    Precipitation in eastern North America is characterized by high concentrations of free acidity and sulfate that are generally attributed to anthropogenic air pollution. The relatively long record of precipitation chemistry measurements at the Penn State MAP3S site is used to analyze the seasonal and interannual variability of precipitation composition in terms of specific mechanisms of atmospheric transport and chemical transformation. The interrelationships of the chemical variables in the precipitation record and in recent air measurements clearly link the precipitation acidity with the wet deposition of sulfate derived from the in-cloud oxidation of sulfur dioxide. High-deposition events are shown through meteorological trajectory analyses to be associated with moist air from the Gulf of Mexico that passes through the upper midwestern parts of the United States. The main chemical factor controlling the deposition of sulfate appears to be the availability of strong oxidants for transforming dissolved sulfur dioxide into aqueous sulfate. Excess sulfur dioxide is expected to exit the storm systems at high altitudes and experience truly long-range transport. This interpretation of the data gives confidence that episodes will occur even after sulfur dioxide emissions have been reduced substantially

  16. Nanoscale precipitation in hot rolled sheet steel

    Science.gov (United States)

    Sun, Jun

    Some newer hot rolled high strength low alloy (HSLA) steels with a single phase ferrite matrix have obtained substantial strengthening from nanoscale precipitation. These HSLA are reported to have a good combination of strength, ductility and hole-expansion ability. In the current work, Gleeble ® 3500 torsion testing was employed to simulate the hot rolling process with varying run-out table cooling rates and coiling temperatures on five microalloyed steels with additions of Ti, Nb, Mo, Cr and V, to investigate the effects of microalloy additions and processing conditions on microstructures as well as mechanical properties. Subsized tensile specimens obtained from as-twisted torsion samples were used to evaluate mechanical properties. The precipitation states of the five steels with different processing conditions were characterized using extraction replica TEM. Comparison of microstructures and mechanical properties was discussed. Characterization of the microstructure via light optical microscopy showed the matrix microstructure was mainly influenced by coiling temperature, which indicates that the transformation from austenite to ferrite occurred during the coiling period. A higher Ti content was shown to reduce the second constituent fractions. Investigation of carbon extraction replica specimens via TEM revealed the presence of nanoscale precipitation. Extensive nanoscale precipitation was observed in most of the specimens having a polygonal ferrite matrix, while in the granular bainite/ferrite microstructure at lower temperatures, fewer microalloy carbides were present. The specimens with polygonal ferrite had similar or higher yield strength than the specimens with granular bainite microstructure, which suggests the effectiveness of precipitation strengthening from extensive nanoscale precipitates. In the Nb-Mo steel, more significant strengthening due to grain refinement was evident. Yield strength values were less than reported for JFE's "NANOHITEN

  17. Origins of the Earth's Diffuse Auroral Precipitation

    Science.gov (United States)

    Ni, Binbin; Thorne, Richard M.; Zhang, Xiaojia; Bortnik, Jacob; Pu, Zuyin; Xie, Lun; Hu, Ze-jun; Han, Desheng; Shi, Run; Zhou, Chen; Gu, Xudong

    2016-04-01

    The Earth's diffuse auroral precipitation provides the major source of energy input into the nightside upper atmosphere and acts as an essential linkage of the magnetosphere-ionosphere coupling. Resonant wave-particle interactions play a dominant role in the scattering of injected plasma sheet electrons, leading to the diffuse auroral precipitation. We review the recent advances in understanding the origin of the diffuse aurora and in quantifying the exact roles of various magnetospheric waves in producing the global distribution of diffuse auroral precipitation and its variability with the geomagnetic activity. Combined scattering by upper-and lower-band chorus accounts for the most intense inner magnetospheric electron diffuse auroral precipitation on the nightside. Dayside chorus can be responsible for the weaker dayside electron diffuse auroral precipitation. Pulsating auroras, the dynamic auroral structures embedded in the diffuse aurora, can be mainly caused by modulation of the excitation of lower band chorus due to macroscopic density variations in the magnetosphere. Electrostatic electron cyclotron harmonic waves are an important or even dominant cause for the nightside electron diffuse auroral precipitation beyond {˜}8Re and can also contribute to the occurrence of the pulsating aurora at high L-shells. Scattering by electromagnetic ion cyclotron waves could quite possibly be the leading candidate responsible for the ion precipitation (especially the reversed-type events of the energy-latitude dispersion) in the regions of the central plasma sheet and ring current. We conclude the review with a summary of current understanding, outstanding questions, and a number of suggestions for future research.

  18. Process for recovering carboxylic acids from sugar cane industry by-products

    OpenAIRE

    Albet, Joël; Pislor, Emilie; Pontalier, Pierre-Yves

    2009-01-01

    Food industry by-products such as molasses and vinasses may provide an important source of organic acids. The aim of this study is to compare three processes, precipitation, chromatography and liquid-liquid extraction, for the recovery of carboxylic acids from sugarcane molasses from Réunion Island. Precipitation was performed with different temperatures by addition of calcium chloride. The results revealed that precipitation can recover aconitic acid efficiently from molasses. Liquid-liquid ...

  19. Chemical composition of atmospheric precipitation on the south of Ukraine (Crimea)

    Science.gov (United States)

    Klymenko, O.; Klymenko, M.

    The data of long monitoring of volume and chemical content of atmospheric precipitation in steppe Crimea near to the large plantations of fruit orchards are given The purpose of researches was detection of acid deposits establishment of connection them dI with chemical structure for the operative tracking behind a condition of air It was established that the sum of precipitations for year was increased basically at the summer deposits The annual volume-weighted logarithmic range of dI values were 4 83-5 73 in precipitation There were more less values in a cold season than in warm one The absolute minimum was equal 3 82 For the researched period mean dI values of atmospheric precipitation in a cold season gradually raised and in warm - was reduced and has reached the minimum in 2000-2001 years It resulted in damages of fruit plants during long term rains in vegetation period The dominant anion in atmospheric precipitation was SO 4 2- which content basically determined of them acidification The important role in this process also belongs to ions NO 3 - and Cl - Mean seasons concentrations of these ions tend to increase It probably may be connected both to distant distribution of emission and with local anthropogenic activity In connection with an establishment of atmospheric precipitation acidification and also incidental and casual phenomenon there is a necessity of their composition monitoring for agricultural areas near to the large fruit plantations for big number years during whole year

  20. The acid rain primer

    International Nuclear Information System (INIS)

    Acid rain continues to be a major problem in North America, and particularly in eastern Canada. This report introduced the topic of acid rain and discussed its formation, measurement, sources, and geographic distribution. The major sources of sulphur dioxide in Canada are smelting metals, burning coal for electrical power generation, industrial emissions (e.g., pulp and paper, petroleum and aluminum industry), and oil and gas extraction and refining. In Canada, the largest source of nitrogen oxide is the burning of fossil fuels by the transportation sector. Problem areas for acid rain in Canada were identified. The effects of acid rain were examined on lakes and aquatic ecosystems, forests and soils, human-made structures and materials, human health, and on visibility. Acid rain policies and programs were then presented from a historical and current context. Ecosystem recovery from acid rain was discussed with reference to acid rain monitoring, atmospheric response to reductions in acid-causing emissions, and ecosystem recovery of lakes, forests, and aquatic ecosystems. Challenges affecting ecosystem recovery were also presented. These challenges include drought and dry weather, decrease of base cations in precipitation, release of sulphate previously stored in soil, mineralization and immobilization of sulphur/sulphates. Last, the report discussed what still needs to be done to improve the problem of acid rain as well as future concerns. These concerns include loss of base cations from forested watersheds and nitrogen deposition and saturation. 21 refs., 2 tabs., 17 figs

  1. Rule-Based Network Service Provisioning

    Directory of Open Access Journals (Sweden)

    Rudy Deca

    2012-10-01

    Full Text Available Due to the unprecedented development of networks, manual network service provisioning is becoming increasingly risky, error-prone, expensive, and time-consuming. To solve this problem,rule-based methods can provide adequate leverage for automating various network management tasks. This paper presents a rule-based solution for automated network service provisioning. The proposed approach captures configuration data interdependencies using high-level, service-specific, user-configurable rules. We focus on the service validation task, which is illustrated by means of a case study.Based on numerical results, we analyse the influence of the network-level complexity factors and rule descriptive features on the rule efficiency. This analysis shows the operators how to increase rule efficiency while keeping the rules simple and the rule set compact. We present a technique that allows operators to increase the error coverage, and we show that high error coverage scales well when the complexity of networks and services increases.We reassess the correlation function between specific rule efficiency and rule complexity metrics found in previous work, and show that this correlation function holds for various sizes, types, and complexities of networks and services.

  2. RPOA Model-Based Optimal Resource Provisioning

    Directory of Open Access Journals (Sweden)

    Noha El. Attar

    2014-01-01

    Full Text Available Optimal utilization of resources is the core of the provisioning process in the cloud computing. Sometimes the local resources of a data center are not adequate to satisfy the users’ requirements. So, the providers need to create several data centers at different geographical area around the world and spread the users’ applications on these resources to satisfy both service providers and customers QoS requirements. By considering the expansion of the resources and applications, the transmission cost and time have to be concerned as significant factors in the allocation process. According to the work of our previous paper, a Resource Provision Optimal Algorithm (RPOA based on Particle Swarm Optimization (PSO has been introduced to find the near optimal resource utilization with considering the customer budget and suitable for deadline time. This paper is considered an enhancement to RPOA algorithm to find the near optimal resource utilization with considering the data transfer time and cost, in addition to the customer budget and deadline time, in the performance measurement.

  3. Homogeneous Precipitation of Nickel Hydroxide Powders

    Energy Technology Data Exchange (ETDEWEB)

    Bora Mavis

    2003-12-12

    Precipitation and characterization of nickel hydroxide powders were investigated. A comprehensive precipitation model incorporating the metal ion hydrolysis, complexation and precipitation reactions was developed for the production of the powders with urea precipitation method. Model predictions on Ni{sup 2+} precipitation rate were confirmed with precipitation experiments carried out at 90 C. Experimental data and model predictions were in remarkable agreement. Uncertainty in the solubility product data of nickel hydroxides was found to be the large contributor to the error. There were demonstrable compositional variations across the particle cross-sections and the growth mechanism was determined to be the aggregation of primary crystallites. This implied that there is a change in the intercalate chemistry of the primary crystallites with digestion time. Predicted changes in the concentrations of simple and complex ions in the solution support the proposed mechanism. The comprehensive set of hydrolysis reactions used in the model described above allows the investigation of other systems provided that accurate reaction constants are available. the fact that transition metal ions like Ni{sup 2+} form strong complexes with ammonia presents a challenge in the full recovery of the Ni{sup 2+}. On the other hand, presence of Al{sup 3+} facilitates the complete precipitation of Ni{sup 2+} in about 3 hours of digestion. A challenge in their predictive modeling studies had been the fact that simultaneous incorporation of more than one metal ion necessitates a different approach than just using the equilibrium constants of hydrolysis, complexation and precipitation reactions. Another limitation of using equilibrium constants is that the nucleation stage of digestion, which is controlled mainly by kinetics, is not fully justified. A new program released by IBM Almaden Research Center (Chemical Kinetics Simulator{trademark}, Version 1.01) lets the user change the order of

  4. 75 FR 8671 - Magnuson-Stevens Act Provisions; General Provisions for Domestic Fisheries; Application for...

    Science.gov (United States)

    2010-02-25

    ... Provisions for Domestic Fisheries; Application for Exempted Fishing Permit AGENCY: National Marine Fisheries.... This includes the proposed regulation, at Sec. 648.87(b)(1)(v) (74 FR 69454, December 31, 2009), that...), food habits, and genetic research. The yellowtail flounder retained would not exceed 60 fish per...

  5. Iron - rare earths separation through double salt, oxalate precipitation - a combined process

    International Nuclear Information System (INIS)

    Sodium diuranate (SDU) obtained at Heavy Water Board (HWB) during uranium recovery from phosphoric acid by D2EHPA-TBP process contains significant amount of iron and valuable rare earths particularly heavier rare earths such as Y, Er, Yb, Dy etc. Separation of valuable rare earths and iron from SDU is essential to get nuclear grade pure uranium. In the present work efforts have been made to devise a solvent extraction cum precipitation process to separate uranium from rare earths and iron followed by selective separation of rare earths from iron by precipitation route

  6. Extraction of rare earth elements from hydrate-phosphate precipitates of apatite processing

    Science.gov (United States)

    Andropov, M. O.; Anufrieva, A. V.; Buynovskiy, A. S.; Makaseev, Y. N.; Mazov, I. N.; Nefedov, R. A.; Sachkov, V. I.; Stepanova, O. B.; Valkov, AV

    2016-01-01

    The features of extraction of rare earth elements (REE) were considered from hydrate-phosphate precipitates of REE of apatite processing by nitric acid technology. The preliminary purification of nitrate solution of REE from impurities of titanium, aluminum, iron, uranium and thorium was suggested to obtain stable solutions not forming precipitates. Washing the extract was recommended with the evaporated reextract that allows to obtain directly on the cascade of REE extraction the concentrated solutions suitable for the separation into groups by the extraction method. Technical decisions were suggested for the separation of REE in groups without the use of salting-out agent.

  7. Novel method for concentrating and drying polymeric nanoparticles: hydrogen bonding coacervate precipitation.

    Science.gov (United States)

    D'Addio, Suzanne M; Kafka, Concepcion; Akbulut, Mustafa; Beattie, Patrick; Saad, Walid; Herrera, Margarita; Kennedy, Michael T; Prud'homme, Robert K

    2010-04-01

    Nanoparticles have significant potential in therapeutic applications to improve the bioavailability and efficacy of active drug compounds. However, the retention of nanometer sizes during concentrating or drying steps presents a significant problem. We report on a new concentrating and drying process for poly(ethylene glycol) (PEG) stabilized nanoparticles, which relies upon the unique pH sensitive hydrogen bonding interaction between PEG and polyacid species. In the hydrogen bonding coacervate precipitation (HBCP) process, PEG protected nanoparticles rapidly aggregate into an easily filterable precipitate upon the addition various polyacids. When the resulting solid is neutralized, the ionization of the acid groups eliminates the hydrogen bonded structure and the approximately 100 nm particles redisperse back to within 10% of their original size when poly(acrylic acid) and citric acid are used and 45% when poly(aspartic acid) is used. While polyacid concentrations of 1-5 wt % were used to form the precipitates, the incorporation of the acid into the PEG layer is approximately 1:1 (acid residue):(ethylene oxide unit) in the final dried precipitate. The redispersion of dried beta-carotene nanoparticles protected with PEG-b-poly(lactide-co-glycolide) polymers dried by HBCP was compared with the redispersion of particles dried by freeze-drying with sucrose as a cryprotectant, spray freeze-drying, and normal drying. Freeze-drying with 0, 2, and 12 wt % sucrose solutions resulted in size increases of 350%, 50%, and 6%, respectively. Spray freeze-drying resulted in particles with increased sizes of 50%, but no cryoprotectant and only moderate redispersion energy was required. Conventional drying resulted in solids that could not be redispersed back to nanometer size. The new HBCP process offers a promising and efficient way to concentrate or convert nanoparticle dispersions into a stable dry powder form.

  8. Precipitated magnetite in alpha effluent treatment

    International Nuclear Information System (INIS)

    Iron present as a fortuitous component of most nuclear plant effluents can be precipitated as magnetite after suitable chemical treatment. The spinel crystal lattice of the magnetite is able to incorporate a wide range of foreign ions which includes many important radioactive species. Provided the operating conditions are well chosen the precipitated magnetite provides an excellent scavenger for many radionuclides and gives a denser more granular solid product to be separated from the effluent than the more visual scavenging agent ferric hydroxide. The conditions under which magnetite can be formed by precipitation and its properties are presented and compared with those of ferric hydroxide. Because magnetite has a high magnetic susceptibility its separation by high gradient magnetic separation becomes a possibility and data relevant to this is presented. (author)

  9. Investigation of Asphaltene Precipitation at Elevated Temperature

    DEFF Research Database (Denmark)

    Andersen, Simon Ivar; Lindeloff, Niels; Stenby, Erling Halfdan

    1998-01-01

    in the extracted fraction, hence there is no room for stirring. The equipment as well as solutions to some of the problems are presented along with precipitation data from 40 to 200 degrees C. The asphaltenes separated are analyzed using FT-ir. The filtrate containing the maltenes was cooled to room temperature......In order to obtain quantitative data on the asphaltene precipitation induced by the addition of n-alkane (heptane) at temperatures above the normal boiling point of the precipitant, a high temperature/high pressure filtration apparatus has been constructed. Oil and alkane are mixed...... and the asphaltenes separating upon cooling was collected and analyzed. The oil and selected maltene fractions and extraction/cleaning solvents were analyzed using GC....

  10. Silicide precipitation strengthened TiAl

    Energy Technology Data Exchange (ETDEWEB)

    Noda, T. [Special Steel Research Laboratory, Daido Steel Co. Ltd., 2-30 Daido-cho, Minami-ku, Nagoya 457 (Japan); Okabe, M. [Special Steel Research Laboratory, Daido Steel Co. Ltd., 2-30 Daido-cho, Minami-ku, Nagoya 457 (Japan); Isobe, S. [Special Steel Research Laboratory, Daido Steel Co. Ltd., 2-30 Daido-cho, Minami-ku, Nagoya 457 (Japan); Sayashi, M. [Materials Research Laboratory, Nissan Research Center, Nissan Motor Co. Ltd., 1 Natushima-cho, Yokosuka 237 (Japan)

    1995-02-28

    Precipitation of a titanium silicide Ti{sub 5}Si{sub 3} was found to be beneficial to improvement of the creep resistance of a fully lamellar Ti-48Al-1.5Cr cast alloy without the sacrifice of tensile properties. The addition of 0.26-0.65 mol% Si generates fine precipitates less than 200 nm in size during aging at 900 C for 5 h. The precipitates are effective obstacles to dislocation motion and raise the stress exponents of power law creep significantly. The specific creep strength of Si-containing alloys is better than that of a conventional Ni-base cast superalloy Inconel 713C at 800 C for 10000 h. ((orig.))

  11. Seasonal and diurnal spatial patterns of precipitation frequency from the TRMM Precipitation Radar

    Science.gov (United States)

    Yuter, Sandra; Biasutti, Michela; Sobel, Adam; Burleyson, Casey

    2010-05-01

    The detailed spatial distribution of rainfall is currently poorly understood over the oceans and for land regions without routine precipitation observation infrastructure. Many of these poorly observed areas are in the tropics where most of the global precipitation occurs. NASA's Tropical Rainfall Measuring Mission (TRMM) satellite was launched in 1997 and continues to operate. TRMM carries the first space-borne Precipitation Radar (PR) which provides high spatial resolution data of the vertical structure of precipitation. We utilize TRMM PR orbit data to construct 5 km x 5 km grids of precipitation statistics over several tropical regions. We focus on several statistics derived from over 10 years of TRMM PR data --the frequency of precipitation above a threshold corresponding to ~0.4 mm/hr, the conditional rain rate near the surface, and conditional radar reflectivities at 3 km and 6 km altitude. Maps of seasonal precipitation frequency reveal the expected large-scale latitudinal variations of the ITCZ and monsoon as well as smaller scale regional precipitation patterns related to sea and land breezes and mountain upslope and downslope flow. In comparison, maps of conditional rain rates and reflectivities indicate less regional variation and primarily illustrate differences between continental and oceanic precipitation. Use of a single satellite-based precipitation instrument over the global tropics facilitates intercomparison among geographic regions. In Asia and the Maritime Continent, there are very high frequencies of precipitation off the coast of Myanmar north toward Bangladesh and off the west coast of Sumatra. The precipitation frequencies off the coast of Myanmar are likely associated with a land breeze but are comparable in magnitude to those for orographic precipitation. The Central Range of the island of New Guinea exhibits a strong diurnal cycle with the precipitation near the crest during day associated with upslope flow and similar magnitude

  12. Chemical precipitation for controlling nitrogen loss during composting.

    Science.gov (United States)

    Ren, Li-Mei; Li, Guo-Xue; Shen, Yun-Jun; Schuchardt, Frank; Lu Peng

    2010-05-01

    Aimed at controlling the nitrogen loss during composting, the mixture of magnesium hydroxide (Mg(OH)( 2)) and phosphoric acid (H(3)PO(4)) (molar ratio 1:2) were utilized as additives to avoid increasing total salinity. In trial TA, the additives were put into absorption bottles connecting with a gas outlet of fermentor (ex situ method); in trial TB, the additives were directly added to the composting materials (in situ method). During the 26 day composting period, the temperature, pH, total organic carbon (TOC), total nitrogen (TN), ammonium nitrogen (NH(4)(+)-N), total phosphorus (TP), available phosphorus (AP) and germination index (GI) were measured. The experimental results show that the additives reduced the pH, while NH( 4)(+)-N and TN were obviously improved. NH(4)( +)-N was 11.9 g kg(-1) and 3 g kg(- 1) in amended compost trial (TB) and unamended compost trial (TA), respectively; TN increased from 26.5 g kg(-1) to 40.3 g kg(-1) in TB and increased from 26.5 g kg( -1) to 26.8 g kg(-1) in TA. Analysis of the TOC and carbon mass revealed that absorbents accelerated the degradation of organic matter. The germination index test showed the maturity of TB (102%) was better than TA (82%) in final compost. Furthermore, TP and AP were also obviously improved. X-ray diffraction analysis of precipitation showed that the precipitation in absorption bottle of TA was newberyite (MgHPO( 4) 3H(2)O), however, the crystal in the TB compost was struvite (MgNH(4)PO(4) 6H(2)O: magnesium ammonium phosphate). These results indicated that Mg(OH)(2) and H(3)PO( 4) could reduce the ammonia emission by struvite crystallization reaction. Optimal conditions for struvite precipitation should be determined for different systems. PMID:19808738

  13. Spatial dependences among precipitation maxima over Belgium

    Directory of Open Access Journals (Sweden)

    S. Vannitsem

    2007-09-01

    Full Text Available For a wide range of applications in hydrology, the probability distribution of precipitation maxima represents a fundamental quantity to build dykes, propose flood planning policies, or more generally, to mitigate the impact of precipitation extremes. Classical Extreme Value Theory (EVT has been applied in this context by usually assuming that precipitation maxima can be considered as Independent and Identically Distributed (IID events, which approximately follow a Generalized Extreme Value distribution (GEV at each recording site. In practice, weather stations records can not be considered as independent in space.

    Assessing the spatial dependences among precipitation maxima provided by two Belgium measurement networks is the main goal of this work. The pairwise dependences are estimated by a variogram of order one, also called madogram, that is specially tailored to be in compliance with spatial EVT and to capture EVT bivariate structures. Our analysis of Belgium precipitation maxima indicates that the degree of dependence varies greatly according to three factors: the distance between two stations, the season (summer or winter and the precipitation accumulation duration (hourly, daily, monthly, etc.. Increasing the duration (from one hour to 20 days strengthens the spatial dependence. The full independence is reached after about 50 km (100 km for summer (winter for a duration of one hour, while for long durations only after a few hundred kilometers. In addition this dependence is always larger in winter than in summer whatever is the duration. An explanation of these properties in terms of the dynamical processes dominating during the two seasons is advanced.

  14. Global Mapping of Provisioning Ecosystem Services

    Science.gov (United States)

    Bingham, Lisa; Straatsma, Menno; Karssenberg, Derek

    2016-04-01

    Attributing monetary value to ecosystem services for decision-making has become more relevant as a basis for decision-making. There are a number of problematic aspects of the calculations, including consistency of economy represented (e.g., purchasing price, production price) and determining which ecosystem subservices to include in a valuation. While several authors have proposed methods for calculating ecosystem services and calculations are presented for global and regional studies, the calculations are mostly broken down into biomes and regions without showing spatially explicit results. The key to decision-making for governments is to be able to make spatial-based decisions because a large spatial variation may exist within a biome or region. Our objective was to compute the spatial distribution of global ecosystem services based on 89 subservices. Initially, only the provisioning ecosystem service category is presented. The provisioning ecosystem service category was calculated using 6 ecosystem services (food, water, raw materials, genetic resources, medical resources, and ornaments) divided into 41 subservices. Global data sets were obtained from a variety of governmental and research agencies for the year 2005 because this is the most data complete and recent year available. All data originated either in tabular or grid formats and were disaggregated to 10 km cell length grids. A lookup table with production values by subservice by country were disaggregated over the economic zone (either marine, land, or combination) based on the spatial existence of the subservice (e.g. forest cover, crop land, non-arable land). Values express the production price in international dollars per hectare. The ecosystem services and the ecosystem service category(ies) maps may be used to show spatial variation of a service within and between countries as well as to specifically show the values within specific regions (e.g. countries, continents), biomes (e.g. coastal, forest

  15. Multiscale analysis of a sustained precipitation event

    Science.gov (United States)

    Knupp, Kevin R.; Williams, Steven F.

    1987-01-01

    Mesoscale data collected during both the satellite precipitation and cloud experiment and the microburst and severe thunderstorm program are analyzed in order to describe features associated with two distinct mesoscale precipitation events that occurred about 10 hours apart over the region of northern Alabama to central Tennessee in June 1986. Data sets used include mesobeta-scale rawinsonde data, surface mesonet data, RADAP data, and GOES images. The present mesoscale environment involved the merger of Hurricane Bonnie remnants with a preexisting midlatitude short-wave trough.

  16. High volume, multiple use, portable precipitator

    Science.gov (United States)

    Carlson, Duane C.

    2011-10-25

    A portable high air volume electrostatic collection precipitator for analyzing air is provided which is a relatively small, self-contained device. The device has a collection electrode adapted to carry a variety of collecting media. An air intake is provided such that air to be analyzed flows through an ionization section with a transversely positioned ionization wire to ionize analytes in the air, and then flows over the collection electrode where ionized analytes are collected. Air flow is maintained at but below turbulent flow, Ionizable constituents in the air are ionized, attracted to the collection electrode, and precipitated in the selected medium which can be removed for analysis.

  17. Analysis on Summer Precipitation Efficiency in Shenyang

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    [Objective] The research aimed to analyze summer precipitation efficiency in Shenyang.[Method] By using the method which estimated the cloud water resource,based on the vertical accumulated liquid water content which was observed by "QFW-1 dual-channel microwave radiometer" and the rain intensity data which had 1min interval and were inverted by "particle laser-based optical measurement" (Parsivel),the precipitation efficiency in Shenyang area during July-August,2007 was analyzed.[Result] When the rain inte...

  18. Electrostatic Precipitation in Nearly Pure Gaseous Nitrogen

    Science.gov (United States)

    Buhler, Charles; Calle, Carlos; Clements, Sid; Cox, Bobby; Ritz, Mindy

    2008-01-01

    Electrostatic precipitation was performed in a nearly pure gaseous nitrogen system as a possible remedy for black dust contaminant from high pressure 6000 psi lines at the NASA Kennedy Space Center. The results of a prototype electrostatic precipitator that was built and tested using nitrogen gas at standard atmospheric pressures is presented. High voltage pulsed waveforms are generated using a rotating spark gap system at 30 Hz. A unique dust delivery system utilizing the Venturi effect was devised that supplies a given amount of dust per unit time for testing purposes.

  19. Five-year record of atmospheric precipitation chemistry in urban Beijing, China

    Science.gov (United States)

    Yang, F.; Tan, J.; Shi, Z. B.; Cai, Y.; He, K.; Ma, Y.; Duan, F.; Okuda, T.; Tanaka, S.; Chen, G.

    2012-02-01

    To investigate the chemical characteristics of precipitation in the polluted urban atmosphere in Beijing and possible mechanisms influencing their variations, a total of 131 event-based precipitation samples were collected from March 2001 to August 2005. The concentrations of major ions in the samples were analyzed by using ion chromatography. Intermediate pH (6.1-7.3) was recorded in approximately two-thirds of the precipitation samples and acidic pH (4.2-5.6) in only 16% of the samples. However, the precipitation acidity was on the growth track and the process was likely being accelerated. SO42-, NO3-, NH4+, and Ca2+ were the most abundant ions in the precipitations, with their single volume-weighted mean (VWM) concentration all above 100 μeq l-1. The two major anions and two major cations accounted for more than 80% of total anionic and cationic mass, respectively. The VWM SO42- concentration decreased by 13% compared to that during 1995-1998, much less than the 58% reduction in the annual average SO2 concentration from 1998 to 2005 in Beijing. What seems more counterintuitive is that the VWM NO3- concentration nearly doubled over the period although the annual average NO2 concentration decreased by 5% from 1998 to 2005. These results imply that the conversion of gaseous precursors to acid compounds and/or the regional transport were reinforced over the decade. The average ratio of neutralizing potential to acidifying potential (i.e. NP/AP) was as high as 1.2 but experienced an evident decline trend. This was mainly ascribed to reduced input of NH4+ and Ca2+ and increased input of NO3-. Furthermore, the equivalent mass ratio of NO3- to non-sea-salt SO42- presented an increasing trend over the study period, suggesting that the contribution of NO3- to the precipitation acidity increased in recent years. However, the mean ratio was only 0.37 ± 0.11 in the study period, which is significantly lower than those reported in some metropolitan areas in developed

  20. The differential impact on stockholder wealth of various antitakeover provisions

    OpenAIRE

    James M. Mahoney; Chamu Sundaramurthy; Mahoney, Joseph T.

    1995-01-01

    This paper examines the relationship between the passage of six types of corporate antitakeover provisions (supermajority, classified boards, fair-price, reduction in cumulative voting, anti-greenmail and poison pills) and stockholder wealth. Our event study from a sample of 38l firms that adopted 486 antitakeover provisions in the 1984-1988 period indicates a strongly negative effect on stockholder wealth, supporting the management entrenchment view of antitakeover provisions. Moreover, the ...

  1. The Impact of Product Market Competition on Training Provision

    DEFF Research Database (Denmark)

    Lai, Tat-kei; Ng, Travis

    While standard models of training focus on how the structure of the input market affects training provisions of firms, this paper investigates the relationship between product market competition and training provision. Using the longitudinal and nationally representative data from Statistics Canada...... training provisions. To the extent that training is a significant source of human capital and industry competitiveness, our empirical results suggest increasing training is a significant channel through which competition raises productivity....

  2. 30 CFR 946.13 - State program provisions set aside.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false State program provisions set aside. 946.13... program provisions set aside. (a) Paragraphs 3.01(a)(1), 3.01(a)(4) and 3.01(a)(5) of the Virginia Coal... inconsistent with and less effective than the Federal provisions for the two-acre exemption and are set...

  3. Eye Tracking Technique for Product Information Provision

    Science.gov (United States)

    Kim, Seoksoo

    This paper is about the study of the design of the product information provision system using eye tracking, which helps users in deciding over purchase of the product, with a system to provide product information that the user needs by tracking eye gaze of the user via Smart phone. The system provides the user with information of the product that attracts the user's eye, by means of users' eye tracking, user information confirmation using face recognition and user's preference for product. Therefore, once it is determined that the user requires a product, the server sends the product information stored in the product information database to the user's Smart phone to provide information the user requires. The customer, provided with product information in real time, can purchase the product that he/she wants efficiently, and avoid excessive consumption with accurate product information.

  4. Provision of genetics services on Guam.

    Science.gov (United States)

    McWalter, Kirsty; Hasegawa, Lianne; Au, Sylvia Mann

    2013-12-01

    Guam's geographic isolation and lack of community resources have resulted in unique healthcare needs. In 2006, the Western States Genetic Services Collaborative (WSGSC) conducted a genetics needs assessment and found that professional development is limited, families lack access to genetic services, and improved coverage of genetic testing is needed. With funding from the WSGSC, a Guam genetics outreach clinic was established and staffed by genetic counselors and a medical geneticist from Hawaii. Four clinics have been held to date. Although several challenges have been encountered, including minimal coverage of genetic testing by Guam insurance companies, limited referrals for families with private insurance, and inappropriate referral indications, the outreach clinic has been successful at increasing access to genetic services and improving professional development. With more collaborative work by staff from Guam, Hawaii, and the WSGSC, provision and reimbursement of genetic services and testing will continue to improve.

  5. Provisions for containment venting in Germany

    Energy Technology Data Exchange (ETDEWEB)

    Wilhelm, J.G.

    1997-08-01

    In this short paper an overlook is given of the systems developed in Germany for filtered containment venting and their implementation in nuclear power plants. More information on the development can be found in the Proceedings of the DOE/NRC Aircleaning Conferences. In Germany, 28.8 % of the electric energy is produced by 19 nuclear power reactors. No new power reactor is expected to be built at least within the next ten years, but France and Germany cooperate in the development of a future European Power Reactor (ERP). This reactor type will be fitted with a core catcher and passive cooling in order to avoid serious consequences of a hypothetical core meltdown accident so that provisions for containment venting are not required. 3 refs., 6 figs., 1 tab.

  6. Lissage de la marge agricole par une provision comptable

    OpenAIRE

    Phélippé-Guinvarc’h, Martial V.

    2008-01-01

    Les producteurs agricoles connaissent de fortes variations de leurs marges opérationnelles, qui peuvent entraîner des pertes financières. Pourtant, le contexte réglementaire actuel français ne permet pas de constituer une provision comptable pour les risques sur la marge. Cet article recommande la constitution d’une nouvelle provision :  la provision pour fluctuation systémique de la marge. Il souligne que cette provision respecte les principes fondateurs de la comptabilité et de la fiscalité...

  7. Monocrotophos Molecularly Imprinted Microspheres Prepared by Precipitation Polymerization in Acetonitrile

    Institute of Scientific and Technical Information of China (English)

    Shoulei Yan; Zhixian Gao; Yanjun Fang; Yiyong Cheng

    2006-01-01

    Molecularly imprinted microspheres (MIP) for monocrotophos have been prepared by precipitation polymerization in acetonitrile (CAN) 60℃, 24 h, using methacrylic acid (MAA), ethylene glycol dimethacrylate (EGDMA) and 2,2-azobisiobutyronitrile (AIBN) as functional monomer, cross-linker and initiator, respectively. The recognition mechanism was elucidated by UV-vis spectra and computer modeling. Equilibrium binding experiment was employed to investigate the rebinding properties, Scatchard analysis showed that specific binding sites formed in the imprinted microspheres, and there were two kinds of binding sites, one was high binding sites, the other was low binding sites. This microspheres can be useful affinity absorbent used for organophosphorus pesticides separation and purification in food and environmental analysis.

  8. An automatic, refrigerated, sequential precipitation sampler

    Science.gov (United States)

    Coscio, M. R.; Pratt, G. C.; Krupa, S. V.

    The design and characteristics of an automated, refrigerated, sequential precipitation sampler are described. This sampler can collect rainfall on an event basis or as sequential segments within a rain event. Samples are sealed upon collection to prevent gas exchange and are refrigerated in situ at 4 ± 2° C. This sampler is commercially available.

  9. Precipitation dendrites in turbulent pipe flows

    Science.gov (United States)

    Angheluta, Luiza; Hawkins, Christopher; Hammer, Øyvind; Jamtveit, Bjørn

    2013-04-01

    Surface precipitation in pipelines, as well as freezing in water pipes is of great concern in many industrial applications where scaling phenomena becomes a control problem of pipe-clogging or an efficiency reduction in transport. Flow blockage often occurs even when only a small fraction is deposited non-uniformly on the walls in the form of dendrites. Dendritic patterns are commonly encountered in surface precipitation from supersaturated solutions, e.g. calcite dendrites, as well as in solidification from undercooled liquids, e.g. freezing of water into ice dendrites. We explore the mathematical similarities between precipitation and freezing processes and, in particular, investigate the effect of fluid flow on the precipitation dendrites on pipe walls. We use a phase field approach to model surface growth coupled with a lattice Boltzmann method that simulates a channel flow at varying Reynolds number. The dendrites orientation and shape depend non-trivially on the ratio between advection and diffusion, i.e. the Peclet number, as well as the Reynolds number. Roughness induced vortices near growing dendrites at high flow rates further affect the branch splitting of dendrites. We show how the transport rate in a pipeline may depend on the different dendritic morphologies, and provide estimates for the flow conditions that correspond to most efficient transport regimes.

  10. Modeling pairwise dependencies in precipitation intensities

    Science.gov (United States)

    Vrac, M.; Naveau, P.; Drobinski, P.

    2007-12-01

    In statistics, extreme events are classically defined as maxima over a block length (e.g. annual maxima of daily precipitation) or as exceedances above a given large threshold. These definitions allow the hydrologist and the flood planner to apply the univariate Extreme Value Theory (EVT) to their time series of interest. But these strategies have two main drawbacks. Firstly, working with maxima or exceedances implies that a lot of observations (those below the chosen threshold or the maximum) are completely disregarded. Secondly, this univariate modeling does not take into account the spatial dependence. Nearby weather stations are considered independent, although their recordings can show otherwise. To start addressing these two issues, we propose a new statistical bivariate model that takes advantages of the recent advances in multivariate EVT. Our model can be viewed as an extension of the non-homogeneous univariate mixture. The two strong points of this latter model are its capacity at modeling the entire range of precipitation (and not only the largest values) and the absence of an arbitrarily fixed large threshold to define exceedances. Here, we adapt this mixture and broaden it to the joint modeling of bivariate precipitation recordings. The performance and flexibility of this new model are illustrated on simulated and real precipitation data.

  11. Modeling pairwise dependencies in precipitation intensities

    Directory of Open Access Journals (Sweden)

    M. Vrac

    2007-12-01

    Full Text Available In statistics, extreme events are classically defined as maxima over a block length (e.g. annual maxima of daily precipitation or as exceedances above a given large threshold. These definitions allow the hydrologist and the flood planner to apply the univariate Extreme Value Theory (EVT to their time series of interest. But these strategies have two main drawbacks. Firstly, working with maxima or exceedances implies that a lot of observations (those below the chosen threshold or the maximum are completely disregarded. Secondly, this univariate modeling does not take into account the spatial dependence. Nearby weather stations are considered independent, although their recordings can show otherwise.

    To start addressing these two issues, we propose a new statistical bivariate model that takes advantages of the recent advances in multivariate EVT. Our model can be viewed as an extension of the non-homogeneous univariate mixture. The two strong points of this latter model are its capacity at modeling the entire range of precipitation (and not only the largest values and the absence of an arbitrarily fixed large threshold to define exceedances. Here, we adapt this mixture and broaden it to the joint modeling of bivariate precipitation recordings. The performance and flexibility of this new model are illustrated on simulated and real precipitation data.

  12. Ethanol precipitation analysis of thymus histone

    NARCIS (Netherlands)

    Bijvoet, P.

    1957-01-01

    An analytical ethanol precipitation technique, similar to 's salting-out procedure, was used for the characterisation of whole thymus histone and the products obtained by preparative ethanol fractionation. The analysis was carried out at —5° C and pH 6.5. Whole histone prepared according to et al.,

  13. in situ Calcite Precipitation for Contaminant Immobilization

    Energy Technology Data Exchange (ETDEWEB)

    Yoshiko Fujita; Robert W. Smith

    2009-08-01

    in situ Calcite Precipitation for Contaminant Immobilization Yoshiko Fujita (Yoshiko.fujita@inl.gov) (Idaho National Laboratory, Idaho Falls, Idaho, USA) Robert W. Smith (University of Idaho-Idaho Falls, Idaho Falls, Idaho, USA) Subsurface radionuclide and trace metal contaminants throughout the U.S. Department of Energy (DOE) complex pose one of DOE’s greatest challenges for long-term stewardship. One promising stabilization mechanism for divalent trace ions, such as the short-lived radionuclide strontium-90, is co-precipitation in calcite. Calcite, a common mineral in the arid western U.S., can form solid solutions with trace metals. The rate of trace metal incorporation is susceptible to manipulation using either abiotic or biotic means. We have previously demonstrated that increasing the calcite precipitation rate by stimulating the activity of urea hydrolyzing microorganisms can result in significantly enhanced Sr uptake. Urea hydrolysis causes the acceleration of calcium carbonate precipitation (and trace metal co-precipitation) by increasing pH and alkalinity, and also by liberating the reactive cations from the aquifer matrix via exchange reactions involving the ammonium ion derived from urea: H2NCONH2 + 3H2O ? 2NH4+ + HCO3- + OH- urea hydrolysis >X:2Ca + 2NH4+ ? 2>X:NH4 + Ca2+ ion exchange Ca2+ + HCO3- + OH- ? CaCO3(s) + H2O calcite precipitation where >X: is a cation exchange site on the aquifer matrix. This contaminant immobilization approach has several attractive features. Urea hydrolysis is catalyzed by the urease enzyme, which is produced by many indigenous subsurface microorganisms. Addition of foreign microbes is unnecessary. In turn the involvement of the native microbes and the consequent in situ generation of reactive components in the aqueous phase (e.g., carbonate and Ca or Sr) can allow dissemination of the reaction over a larger volume and/or farther away from an amendment injection point, as compared to direct addition of the reactants at

  14. Distribution and turnover of 137Cs in birch forest ecosystems: influence of precipitation chemistry

    International Nuclear Information System (INIS)

    The aim of the present work was to study radioactive caesium in soil and plants from birch forests subject to different chemical climate. Four areas and three types of precipitation regimes were considered, representing a natural climatic range found in Norway: (A) acidic precipitation (southernmost part of the country); (B) precipitation rich in “sea salts”/marine cations (coastal areas); and (C) + (D) low concentrations of sea salts (inland areas). The results showed significant regional differences in plant uptake between the investigated areas. For instance the aggregated soil-to-plant transfer coefficients (Tag) were generally up to 7–8 times higher for the area receiving acid rain. Differences in caesium speciation partly explained the regional variability - e.g. the exchangeable fraction ranged from 1 to 40% (with the largest fraction of exchangeable caesium found in southernmost Norway). Transfer coefficients estimated on the basis of exchangeable fractions showed no significant differences between the areas of highest (A) and lowest (C) Tags. However, exchangeable fractions taken into consideration, the uptake of 137Cs in plants in the acid rain-influenced area is still about twice that in the sea salt influenced area B. A significantly lower concentration of soluble base cations and a higher share of acid components in soils in area A is a likely explanation for this observation. - Highlights: ► Precipitation quality affects soil chemistry and plant uptake of Cs. ► Soil-to-plant transfer of Cs was highest in a coastal area receiving acid rain. ► Differences in Cs speciation partly explained regional transfer variability.

  15. Energetic electron precipitation during sawtooth injections

    Directory of Open Access Journals (Sweden)

    A. J. Kavanagh

    2007-06-01

    Full Text Available We present simultaneous riometer observations of cosmic noise absorption in the nightside and dawn-noon sectors during sawtooth particle injections during 18 April 2002. Energetic electron precipitation (>30 keV is a feature of magnetospheric substorms and cosmic radio noise absorption acts as a proxy for qualitatively measuring this precipitation. This event provides an opportunity to compare the absorption that accompanies periodic electron injections with the accepted paradigm of substorm-related absorption. We consider whether the absorption is consistent with the premise that these injections are quasi-periodic substorms and study the effects of sustained activity on the level of precipitation. Four consecutive electron injection events have been identified from the LANL (Los Alamos National Laboratory geosynchronous data; the first two showing that additional activity can occur within the 2–4 h sawtooth periodicity. The first three events have accompanying absorption on the nightside that demonstrate good agreement with the expected pattern of substorm-absorption: discrete spike events with poleward motion at the onset followed by equatorward moving structures and more diffuse absorption, correlated with optical observations. Dayside absorption is linked to gradient-curvature drifting electrons observed at geostationary orbit and it is shown that low fluxes can lead to a lack of absorption as precipitation is suppressed; precipitation begins when the drifting electron flux surpasses some critical level following continuous injections of electrons from the magnetotail. In addition it is shown that the apparent motion of absorption determined from an azimuthal chain of riometers exhibits an acceleration that may be indicative of an energisation of the drifting electron population.

  16. Water Management Applications of Advanced Precipitation Products

    Science.gov (United States)

    Johnson, L. E.; Braswell, G.; Delaney, C.

    2012-12-01

    Advanced precipitation sensors and numerical models track storms as they occur and forecast the likelihood of heavy rain for time frames ranging from 1 to 8 hours, 1 day, and extended outlooks out to 3 to 7 days. Forecast skill decreases at the extended time frames but the outlooks have been shown to provide "situational awareness" which aids in preparation for flood mitigation and water supply operations. In California the California-Nevada River Forecast Centers and local Weather Forecast Offices provide precipitation products that are widely used to support water management and flood response activities of various kinds. The Hydrometeorology Testbed (HMT) program is being conducted to help advance the science of precipitation tracking and forecasting in support of the NWS. HMT high-resolution products have found applications for other non-federal water management activities as well. This presentation will describe water management applications of HMT advanced precipitation products, and characterization of benefits expected to accrue. Two case examples will be highlighted, 1) reservoir operations for flood control and water supply, and 2) urban stormwater management. Application of advanced precipitation products in support of reservoir operations is a focus of the Sonoma County Water Agency. Examples include: a) interfacing the high-resolution QPE products with a distributed hydrologic model for the Russian-Napa watersheds, b) providing early warning of in-coming storms for flood preparedness and water supply storage operations. For the stormwater case, San Francisco wastewater engineers are developing a plan to deploy high resolution gap-filling radars looking off shore to obtain longer lead times on approaching storms. A 4 to 8 hour lead time would provide opportunity to optimize stormwater capture and treatment operations, and minimize combined sewer overflows into the Bay.ussian River distributed hydrologic model.

  17. Quantification of asphaltene precipitation by scaling equation

    Science.gov (United States)

    Janier, Josefina Barnachea; Jalil, Mohamad Afzal B. Abd.; Samin, Mohamad Izhar B. Mohd; Karim, Samsul Ariffin B. A.

    2015-02-01

    Asphaltene precipitation from crude oil is one of the issues for the oil industry. The deposition of asphaltene occurs during production, transportation and separating process. The injection of carbon dioxide (CO2) during enhance oil recovery (EOR) is believed to contribute much to the precipitation of asphaltene. Precipitation can be affected by the changes in temperature and pressure on the crude oil however, reduction in pressure contribute much to the instability of asphaltene as compared to temperature. This paper discussed the quantification of precipitated asphaltene in crude oil at different high pressures and at constant temperature. The derived scaling equation was based on the reservoir condition with variation in the amount of carbon dioxide (CO2) mixed with Dulang a light crude oil sample used in the experiment towards the stability of asphaltene. A FluidEval PVT cell with Solid Detection System (SDS) was the instrument used to gain experimental knowledge on the behavior of fluid at reservoir conditions. Two conditions were followed in the conduct of the experiment. Firstly, a 45cc light crude oil was mixed with 18cc (40%) of CO2 and secondly, the same amount of crude oil sample was mixed with 27cc (60%) of CO2. Results showed that for a 45cc crude oil sample combined with 18cc (40%) of CO2 gas indicated a saturation pressure of 1498.37psi and asphaltene onset point was 1620psi. Then for the same amount of crude oil combined with 27cc (60%) of CO2, the saturation pressure was 2046.502psi and asphaltene onset point was 2230psi. The derivation of the scaling equation considered reservoir temperature, pressure, bubble point pressure, mole percent of the precipitant the injected gas CO2, and the gas molecular weight. The scaled equation resulted to a third order polynomial that can be used to quantify the amount of asphaltene in crude oil.

  18. A global satellite-assisted precipitation climatology

    Science.gov (United States)

    Funk, C.; Verdin, A.; Michaelsen, J.; Peterson, P.; Pedreros, D.; Husak, G.

    2015-10-01

    Accurate representations of mean climate conditions, especially in areas of complex terrain, are an important part of environmental monitoring systems. As high-resolution satellite monitoring information accumulates with the passage of time, it can be increasingly useful in efforts to better characterize the earth's mean climatology. Current state-of-the-science products rely on complex and sometimes unreliable relationships between elevation and station-based precipitation records, which can result in poor performance in food and water insecure regions with sparse observation networks. These vulnerable areas (like Ethiopia, Afghanistan, or Haiti) are often the critical regions for humanitarian drought monitoring. Here, we show that long period of record geo-synchronous and polar-orbiting satellite observations provide a unique new resource for producing high-resolution (0.05°) global precipitation climatologies that perform reasonably well in data-sparse regions. Traditionally, global climatologies have been produced by combining station observations and physiographic predictors like latitude, longitude, elevation, and slope. While such approaches can work well, especially in areas with reasonably dense observation networks, the fundamental relationship between physiographic variables and the target climate variables can often be indirect and spatially complex. Infrared and microwave satellite observations, on the other hand, directly monitor the earth's energy emissions. These emissions often correspond physically with the location and intensity of precipitation. We show that these relationships provide a good basis for building global climatologies. We also introduce a new geospatial modeling approach based on moving window regressions and inverse distance weighting interpolation. This approach combines satellite fields, gridded physiographic indicators, and in situ climate normals. The resulting global 0.05° monthly precipitation climatology, the Climate

  19. A global satellite assisted precipitation climatology

    Directory of Open Access Journals (Sweden)

    C. Funk

    2015-05-01

    Full Text Available Accurate representations of mean climate conditions, especially in areas of complex terrain, are an important part of environmental monitoring systems. As high-resolution satellite monitoring information accumulates with the passage of time, it can be increasingly useful in efforts to better characterize the earth's mean climatology. Current state-of-the-science products rely on complex and sometimes unreliable relationships between elevation and station-based precipitation records, which can result in poor performance in food and water insecure regions with sparse observation networks. These vulnerable areas (like Ethiopia, Afghanistan, or Haiti are often the critical regions for humanitarian drought monitoring. Here, we show that long period of record geo-synchronous and polar-orbiting satellite observations provide a unique new resource for producing high resolution (0.05° global precipitation climatologies that perform reasonably well in data sparse regions. Traditionally, global climatologies have been produced by combining station observations and physiographic predictors like latitude, longitude, elevation, and slope. While such approaches can work well, especially in areas with reasonably dense observation networks, the fundamental relationship between physiographic variables and the target climate variables can often be indirect and spatially complex. Infrared and microwave satellite observations, on the other hand, directly monitor the earth's energy emissions. These emissions often correspond physically with the location and intensity of precipitation. We show that these relationships provide a good basis for building global climatologies. We also introduce a new geospatial modeling approach based on moving window regressions and inverse distance weighting interpolation. This approach combines satellite fields, gridded physiographic indicators, and in situ climate normals. The resulting global 0.05° monthly precipitation climatology

  20. A global satellite assisted precipitation climatology

    Science.gov (United States)

    Funk, Christopher C.; Verdin, Andrew P.; Michaelsen, Joel C.; Pedreros, Diego; Husak, Gregory J.; Peterson, P.

    2015-01-01

    Accurate representations of mean climate conditions, especially in areas of complex terrain, are an important part of environmental monitoring systems. As high-resolution satellite monitoring information accumulates with the passage of time, it can be increasingly useful in efforts to better characterize the earth's mean climatology. Current state-of-the-science products rely on complex and sometimes unreliable relationships between elevation and station-based precipitation records, which can result in poor performance in food and water insecure regions with sparse observation networks. These vulnerable areas (like Ethiopia, Afghanistan, or Haiti) are often the critical regions for humanitarian drought monitoring. Here, we show that long period of record geo-synchronous and polar-orbiting satellite observations provide a unique new resource for producing high resolution (0.05°) global precipitation climatologies that perform reasonably well in data sparse regions. Traditionally, global climatologies have been produced by combining station observations and physiographic predictors like latitude, longitude, elevation, and slope. While such approaches can work well, especially in areas with reasonably dense observation networks, the fundamental relationship between physiographic variables and the target climate variables can often be indirect and spatially complex. Infrared and microwave satellite observations, on the other hand, directly monitor the earth's energy emissions. These emissions often correspond physically with the location and intensity of precipitation. We show that these relationships provide a good basis for building global climatologies. We also introduce a new geospatial modeling approach based on moving window regressions and inverse distance weighting interpolation. This approach combines satellite fields, gridded physiographic indicators, and in situ climate normals. The resulting global 0.05° monthly precipitation climatology, the Climate

  1. Preliminary Study on the Legal Conflict of our Country Marriage Alternative Provisions and Supplementary Provisions in the National Autonomous Areas

    Institute of Scientific and Technical Information of China (English)

    ZHAO Yingpeng

    2015-01-01

    The national autonomous areas exercise an important way of autonomy power to make adaptive or supplementary provisions to the existing laws, and the diversity between different ethnic groups determines the adaptive or supplementary provisions that are bound to the existence of conflict in the legislative content and legal application. On the basis of adaptive or supplementary provisions, this paper carries out the analysis on the law conflict problems of marriage adaptive or supplementary provisions, hoping to start a discussion, and make scholars foeusing on the conflict of national regional autonomy law.

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

    Directory of Open Access Journals (Sweden)

    A. Sorooshian

    2013-04-01

    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 decreased at the majority of sites due mostly to air pollution regulations of SO42− precursors.

  3. 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.

  4. Deducing high-altitude precipitation from glacier mass balance measurements

    Science.gov (United States)

    Giesen, Rianne H.; Immerzeel, Walter W.; Wanders, Niko

    2016-04-01

    The spatial distribution of precipitation in mountainous terrain is generally not well known due to underrepresentation of gauge observations at higher elevations. Precipitation tends to increase with elevation, but since observations are mainly performed in the valleys, the vertical precipitation gradient cannot be deduced from these measurements. Furthermore, the spatial resolution of gridded meteorological data is often too coarse to resolve individual mountain chains. Still, a reliable estimate of high-elevation precipitation is required for many hydrological applications. We present a method to determine the vertical precipitation gradient in mountainous terrain, making use of glacier mass balance observations. These measurements have the advantage that they provide a basin-wide precipitation estimate at high elevations. The precipitation gradient is adjusted until the solid precipitation over the glacier area combined with the calculated melt gives the measured annual glacier mass balance. Results for the glacierized regions in Central Europe and Scandinavia reveal spatially coherent patterns, with predominantly positive precipitation gradients ranging from -4 to +28 % (100 m)‑1. In some regions, precipitation amounts at high elevations are up to four times as large as in the valleys. A comparison of the modelled winter precipitation with observed snow accumulation on glaciers shows a good agreement. Precipitation measured at the few high-altitude meteorological stations is generally lower than our estimate, which may result from precipitation undercatch. Our findings will improve the precipitation forcing for glacier modelling and hydrological studies in mountainous terrain.

  5. 45 CFR 650.5 - Special patent provisions.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 3 2010-10-01 2010-10-01 false Special patent provisions. 650.5 Section 650.5 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION PATENTS § 650.5 Special patent provisions. At the request of the prospective awardee or on recommendation...

  6. 48 CFR 41.501 - Solicitation provision and contract clauses.

    Science.gov (United States)

    2010-10-01

    ... contract clauses. 41.501 Section 41.501 Federal Acquisition Regulations System FEDERAL ACQUISITION... Contract Clauses 41.501 Solicitation provision and contract clauses. (a) Because the terms and conditions... substantially the same as the provision at 52.241-1, Electric Service Territory Compliance Representation,...

  7. 7 CFR 457.131 - Macadamia nut crop insurance provisions.

    Science.gov (United States)

    2010-01-01

    ...) regulations, 7 CFR part 400, subpart G, and applicable policy provisions unless damage or changes to the... 7 Agriculture 6 2010-01-01 2010-01-01 false Macadamia nut crop insurance provisions. 457.131... INSURANCE CORPORATION, DEPARTMENT OF AGRICULTURE COMMON CROP INSURANCE REGULATIONS § 457.131 Macadamia...

  8. 50 CFR 27.31 - General provisions regarding vehicles.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false General provisions regarding vehicles. 27... Vehicles § 27.31 General provisions regarding vehicles. Travel in or use of any motorized or other vehicles... wildlife refuge or portion thereof is located shall govern traffic and the operation and use of...

  9. 48 CFR 52.241 - Utility Services Provisions and Clauses.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 2 2010-10-01 2010-10-01 false Utility Services Provisions and Clauses. 52.241 Section 52.241 Federal Acquisition Regulations System FEDERAL ACQUISITION... Clauses 52.241 Utility Services Provisions and Clauses....

  10. 48 CFR 970.5201 - Text of provisions and clauses.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Text of provisions and clauses. 970.5201 Section 970.5201 Federal Acquisition Regulations System DEPARTMENT OF ENERGY AGENCY... for Management and Operating Contracts 970.5201 Text of provisions and clauses....

  11. 26 CFR 509.102 - Applicable provisions of law.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 19 2010-04-01 2010-04-01 false Applicable provisions of law. 509.102 Section... UNDER TAX CONVENTIONS SWITZERLAND General Income Tax § 509.102 Applicable provisions of law. (a) General... reason of any alteration of law in relation to internal revenue. (b) Retroactivity of regulations...

  12. 40 CFR 63.1321 - Batch process vents provisions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Batch process vents provisions. 63.1321... Standards for Hazardous Air Pollutant Emissions: Group IV Polymers and Resins § 63.1321 Batch process vents provisions. (a) Batch process vents. Except as specified in paragraphs (b) through (d) of this...

  13. 40 CFR 57.108 - Comparable existing SIP provisions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 5 2010-07-01 2010-07-01 false Comparable existing SIP provisions. 57... (CONTINUED) PRIMARY NONFERROUS SMELTER ORDERS General § 57.108 Comparable existing SIP provisions... subject under the applicable EPA-approved State Implementation Plan (SIP) for sulfur dioxide in lieu...

  14. 40 CFR 52.1390 - Missoula variance provision.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Missoula variance provision. 52.1390... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Montana § 52.1390 Missoula variance provision. The Missoula City-County Air Pollution Control Program's Chapter X, Variances, which was...

  15. Summary of Head Start Provisions on Homelessness and Foster Care

    Science.gov (United States)

    National Association for the Education of Homeless Children and Youth, 2008

    2008-01-01

    On Wednesday, December 12, President Bush signed the "Improving Head Start for School Readiness Act of 2007" into law. The legislation reauthorizes the Head Start Act and contains numerous provisions on homelessness and foster care. A summary of those provisions is provided in this paper.

  16. 9 CFR 145.5 - Specific provisions for participating flocks.

    Science.gov (United States)

    2010-01-01

    ... flocks. 145.5 Section 145.5 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... General Provisions § 145.5 Specific provisions for participating flocks. (a) Poultry equipment, and... recommended in §§ 147.21 and 147.22 (a) and (e) of this chapter. The participating flock, its eggs, and...

  17. 48 CFR 50.206 - Solicitation provisions and contract clause.

    Science.gov (United States)

    2010-10-01

    ... REGULATION CONTRACT MANAGEMENT EXTRAORDINARY CONTRACTUAL ACTIONS AND THE SAFETY ACT Support Anti-terrorism by Fostering Effective Technologies Act of 2002 50.206 Solicitation provisions and contract clause. (a) Insert the provision at 52.250-2, SAFETY Act Coverage Not Applicable, in solicitations if— (1) The...

  18. 75 FR 15390 - Gap in Termination Provisions; Inquiry

    Science.gov (United States)

    2010-03-29

    ... Copyright Office 37 CFR Part 201 Gap in Termination Provisions; Inquiry AGENCY: Copyright Office, Library of... ] for grants made in 1978 will begin to expire next year. Termination provisions provide authors with a... during a five-year period beginning at the end of fifty-six years from the date copyright was...

  19. 49 CFR 578.7 - Criminal safe harbor provision.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 7 2010-10-01 2010-10-01 false Criminal safe harbor provision. 578.7 Section 578... SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) CIVIL AND CRIMINAL PENALTIES § 578.7 Criminal safe harbor provision. (a) Scope. This section sets forth the requirements regarding...

  20. 40 CFR 1068.301 - What general provisions apply?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false What general provisions apply? 1068.301 Section 1068.301 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS GENERAL COMPLIANCE PROVISIONS FOR ENGINE PROGRAMS Imports § 1068.301 What...

  1. 26 CFR 1.9000-7 - Provisions for estimated tax.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 13 2010-04-01 2010-04-01 false Provisions for estimated tax. 1.9000-7 Section... TAX (CONTINUED) INCOME TAXES General Actuarial Valuations § 1.9000-7 Provisions for estimated tax. (a... section 294(d) (relating to estimated tax) of the Internal Revenue Code of 1939 shall be computed as...

  2. Light-Path Provisioning of the WDM Optical Networks

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Provisioning of the WDM optical networks has been a challenge problem because it involves both the physical topology and the logical topology. In addition, the stochastic effects of the traffic mix must be properly characterized. This paper proposes a generic light-path provisioning model and suggests a solution procedure based on a recent mathematical achievement. A case study is also reported.

  3. Organic Food and the Plural Moralities of Food Provisioning

    Science.gov (United States)

    Andersen, Anne Holst

    2011-01-01

    The aim of this paper is twofold. The first aim is to unfold the moral complexity of organic food consumption as part of household food provisioning. By acknowledging this complexity, and the difficulty of determining what is "good" and "right" in food provisioning, the idea is to allow for a better understanding of how organic food may, or may…

  4. 14 CFR 21.261 - Equivalent safety provisions.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Equivalent safety provisions. 21.261 Section 21.261 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION....261 Equivalent safety provisions. The manufacturer shall obtain the Administrator's concurrence on...

  5. Pure Redistribution and the Provision of Public Goods

    DEFF Research Database (Denmark)

    Sausgruber, Rupert; Tyran, Jean-Robert

    We study pure redistribution as a device to increase cooperation and efficiency in the provision of public goods. Experimental subjects play a two-stage game. The first stage is the standard linear public goods game. In the second stage, subjects can redistribute payoffs among other subjects...... cooperation in the provision of public goods...

  6. Pure redistribution and the provision of public goods

    DEFF Research Database (Denmark)

    Sausgruber, Rupert; Tyran, Jean-Robert

    2007-01-01

    We show that a simple redistribution scheme can increase the provision of public goods and that the scheme is popular. This suggests that imposed redistribution as in the mechanism by Falkinger [Falkinger, J., 1996. Efficient private provision of public goods when deviations from average...

  7. 29 CFR 1910.19 - Special provisions for air contaminants.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 5 2010-07-01 2010-07-01 false Special provisions for air contaminants. 1910.19 Section 1910.19 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION... Standards § 1910.19 Special provisions for air contaminants. (a) Asbestos, tremolite, anthophyllite,...

  8. 18 CFR 706.212 - Miscellaneous statutory provisions.

    Science.gov (United States)

    2010-04-01

    ... EMPLOYEE RESPONSIBILITIES AND CONDUCT Conduct and Responsibilities of Employees § 706.212 Miscellaneous statutory provisions. The attention of each employee is directed to the following statutory provisions: (a... Government Service. (b) Chapter 11 of Title 18, United States Code, relating to bribery, graft and...

  9. 24 CFR 966.6 - Prohibited lease provisions.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Prohibited lease provisions. 966.6... DEVELOPMENT PUBLIC HOUSING LEASE AND GRIEVANCE PROCEDURE Dwelling Leases, Procedures and Requirements § 966.6 Prohibited lease provisions. Lease clauses of the nature described below shall not be included in new...

  10. 40 CFR 262.86 - Provisions relating to recognized traders.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Provisions relating to recognized traders. 262.86 Section 262.86 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID... Hazardous Waste for Recovery within the OECD § 262.86 Provisions relating to recognized traders. (a)...

  11. 28 CFR 545.26 - Performance pay provisions.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Performance pay provisions. 545.26... WORK AND COMPENSATION Inmate Work and Performance Pay Program § 545.26 Performance pay provisions. (a... effective management of the overall performance pay program, the percentage of inmates assigned to...

  12. 48 CFR 814.201-6 - Solicitation provisions.

    Science.gov (United States)

    2010-10-01

    ... electronic means. (b) In an invitation for bid for supplies, equipment, or services (other than construction... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 814.201-6 Solicitation provisions. (a) The contracting officer must place the provision entitled “Caution to Bidders-Bid Envelopes,”...

  13. 48 CFR 5119.1071 - Solicitation provisions and contract clauses.

    Science.gov (United States)

    2010-10-01

    ... THE ARMY ACQUISITION REGULATIONS SMALL BUSINESS AND SMALL DISADVANTAGED BUSINESS CONCERNS Small Business Competitiveness Demonstration Program 5119.1071 Solicitation provisions and contract clauses. (a) DFARS provision 252.219-7012 shall be inserted in all solicitations issued under the Small...

  14. 29 CFR 2200.52 - General provisions governing discovery.

    Science.gov (United States)

    2010-07-01

    ... the hearing through new requests for supplementation of prior responses. (j) Filing of discovery... 29 Labor 9 2010-07-01 2010-07-01 false General provisions governing discovery. 2200.52 Section... COMMISSION RULES OF PROCEDURE Prehearing Procedures and Discovery § 2200.52 General provisions...

  15. 31 CFR 50.18 - Notice required by reinstatement provision.

    Science.gov (United States)

    2010-07-01

    ... provision. 50.18 Section 50.18 Money and Finance: Treasury Office of the Secretary of the Treasury TERRORISM... reinstatement provision. (a) Nullification of terrorism exclusion. Any terrorism exclusion in a contract for... losses that would otherwise be insured losses. (b) Reinstatement of terrorism exclusion....

  16. 30 CFR 77.1304 - Blasting agents; special provisions.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Blasting agents; special provisions. 77.1304... COAL MINES Explosives and Blasting § 77.1304 Blasting agents; special provisions. (a) Sensitized ammonium nitrate blasting agents, and the components thereof prior to mixing, shall be mixed and stored...

  17. 12 CFR 227.13 - Unfair credit contract provisions.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Unfair credit contract provisions. 227.13... RESERVE SYSTEM UNFAIR OR DECEPTIVE ACTS OR PRACTICES (REGULATION AA) Credit Practices Rule § 227.13 Unfair credit contract provisions. It is an unfair act or practice for a bank to enter into a consumer...

  18. 40 CFR 90.808 - Ordered recall provisions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Ordered recall provisions. 90.808...-Related Defect Reporting Requirements, Voluntary Emission Recall Program, Ordered Recalls § 90.808 Ordered recall provisions. (a) Effective with respect to Phase 2 small SI engines: (1) If the...

  19. 46 CFR 401.425 - Provision for additional pilot.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false Provision for additional pilot. 401.425 Section 401.425... REGULATIONS Rates, Charges, and Conditions for Pilotage Services § 401.425 Provision for additional pilot. The... Authority, Ltd., Canada, may require the assignment of two pilots to a ship upon request of the ship or...

  20. Chemistry of United States precipitation. Final report on the national precipitation sampling network

    Energy Technology Data Exchange (ETDEWEB)

    Lodge, J.P. Jr.; Pate, J.B.; Basbergill, W.; Swanson, G.S.; Hill, K.C.; Lorange, E.; Lazrus, A.L.

    1968-01-01

    Atmospheric precipitation washes large quantities of particulate and gaseous materials from air, and thus provides a means of studying contamination of the atmosphere. The relationships between the concentration of constituents in air and their concentrations in precipitation are not known with quantitative certainty. However, it is believed that the concentration patterns of contaminants in precipitation reflect their patterns in air. Moreover, though analysis of precipitation water does not reveal absolute values for air contamination, it does provide a means of monitoring changes in contamination with time. The purposes of the project are: (1) to determine mean benchmark values of contaminants throughout the country; (2) to detect possible trends in these values over long periods of time; (3) to observe seasonal fluctuations and geographical distributions which may reveal the sources of these atmospheric contaminants. 48 references, 27 figures, 5 tables.

  1. The behaviour of pharmaceuticals and heavy metals during struvite precipitation in urine.

    Science.gov (United States)

    Ronteltap, Mariska; Maurer, Max; Gujer, Willi

    2007-05-01

    Separating urine from wastewater at the source reduces the costs of extensive wastewater treatment. Recovering the nutrients from urine and reusing them for agricultural purposes adds resource saving to the benefits. Phosphate can be recovered in the form of struvite (magnesium ammonium phosphate). In this paper, the behaviour of pharmaceuticals and heavy metals during the precipitation of struvite in urine is studied. When precipitating struvite in urine spiked with hormones and non-ionic, acidic and basic pharmaceuticals, the hormones and pharmaceuticals remain in solution for more than 98%. For heavy metals, initial experiments were performed to study metal solubility in urine. Solubility is shown to be affected by the chemical conditions of stored and therefore hydrolysed urine. Thermodynamic modelling reveals low or very low equilibrium solute concentrations for cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), nickel (Ni) and lead (Pb). Experiments confirmed Cd, Cu and Pb carbonate and hydroxide precipitation upon metal addition in stored urine with a reaction half-life of ca. 7 days. For all metals considered, the maximum specific metal concentrations per gram phosphate or nitrogen showed to be typically several orders of magnitudes lower in urine than in commercially available fertilizers and manure. Heavy metals in struvite precipitated from normal stored urine could not be detected. Phosphate recovery from urine over struvite precipitation is shown to render a product free from most organic micropollutants and containing only a fraction of the already low amounts of heavy metals in urine. PMID:17368503

  2. Global cloud and precipitation chemistry and wet deposition: tropospheric model simulations with ECHAM5/MESSy1

    Directory of Open Access Journals (Sweden)

    H. Tost

    2007-01-01

    Full Text Available The representation of cloud and precipitation chemistry and subsequent wet deposition of trace constituents in global atmospheric chemistry models is associated with large uncertainties. To improve the simulated trace gas distributions we apply the new submodel SCAV, which includes detailed cloud and precipitation chemistry and present results of the atmospheric chemistry general circulation model ECHAM5/MESSy1. A good agreement with observed wet deposition fluxes for species causing acid rain is obtained. The new scheme enables prognostic calculations of the pH of clouds and precipitation, and these results are also in accordance with observations. We address the influence of detailed cloud and precipitation chemistry on trace constituents based on sensitivity simulations. The results confirm previous results from regional scale and box models, and we extend the analysis to the role of aqueous phase chemistry on the global scale. Some species are directly affected through multiphase removal processes, and many also indirectly through changes in oxidant concentrations, which in turn have an impact on the species lifetime. While the overall effect on tropospheric ozone is relatively small (<10%, regional effects on O3 can reach ~20%, and several important compounds (e.g., H2O2, HCHO are substantially depleted by clouds and precipitation.

  3. Global cloud and precipitation chemistry and wet deposition: tropospheric model simulations with ECHAM5/MESSy1

    Directory of Open Access Journals (Sweden)

    J. Lelieveld

    2007-05-01

    Full Text Available The representation of cloud and precipitation chemistry and subsequent wet deposition of trace constituents in global atmospheric chemistry models is associated with large uncertainties. To improve the simulated trace gas distributions we apply the new submodel SCAV, which includes detailed cloud and precipitation chemistry and present results of the atmospheric chemistry general circulation model ECHAM5/MESSy1. A good agreement with observed wet deposition fluxes for species causing acid rain is obtained. The new scheme enables prognostic calculations of the pH of clouds and precipitation, and these results are also in accordance with observations. We address the influence of detailed cloud and precipitation chemistry on trace constituents based on sensitivity simulations. The results confirm previous results from regional scale and box models, and we extend the analysis to the role of aqueous phase chemistry on the global scale. Some species are directly affected through multiphase removal processes, and many also indirectly through changes in oxidant concentrations, which in turn have an impact on the species lifetime. While the overall effect on tropospheric ozone is relatively small (3 can reach ≈20%, and several important compounds (e.g., H2O2, HCHO are substantially depleted by clouds and precipitation.

  4. Spectroscopic study of Se(IV) removal from water by reductive precipitation using sulfide.

    Science.gov (United States)

    Jung, Bahngmi; Safan, Aya; Batchelor, Bill; Abdel-Wahab, Ahmed

    2016-11-01

    This study investigates the removal of selenium (IV) from water by reductive precipitation using sodium sulfide at neutral pH. Also, it examines the application of UV light as an activating method to enhance reductive precipitation. Furthermore, this work evaluates the effects of sulfide dose and solution pH on behavior of Se(IV) reduction. Selenium was effectively removed in sulfide solution at both neutral and acidic pH. UV irradiation did not enhance removal efficiency of Se(IV) at conditions tested, but it affected solids morphology and composition. SEM/EDS and XPS results showed that selenite was reduced to elemental Se or Se-S precipitates (e.g. SenS8-n) in sulfide solution. High resolution S 2p XPS spectra suggested the presence of sulfur-containing anions (e.g. S2O3(2-), HSO3(-), etc.) or elemental S (S(0)), monosulfide (S(2-)), and polysulfides (Sn(2-)), which could be produced from sulfide photolysis or reaction with Se. In addition, large aggregates of irregular shape, which suggest Se-S precipitates or elemental sulfur, were found more prominently at pH 4 than at pH 7, and they were more noticeable in the presence of UV with longer reaction times. In addition, XRD patterns showed that gray elemental Se solids were dominant in experiments without UV, whereas Se-S precipitates (Se3S5) with an orange color were found in those with UV. PMID:27552695

  5. DEGREE OF ACIDIFICATION OF PRECIPITATION IN BIELSKO-BIAŁA REGION

    Directory of Open Access Journals (Sweden)

    Henryk Kasza

    2014-10-01

    Full Text Available In the paper results of long-term studies on acidification of water precipitation conducted in seven research points located near Bielsko-Biała were introduced. In each point period of study lasted ca. 1 year. The research was performed in the years 2002-2010. The range of pH of precipitation varied between 3.35 to 7.22. Majority of precipitation samples, because approximately 86% had pH < 5.6 i.e. lower than natural level, which indicated the presence of acidifying substances. Amongst samples of precipitation 47.6% were significantly and strongly acidic i.e. pH < 4.5. The rainwater with pH < 5.6 was more frequent than in more industrialized part of Silesian voivodship. In the investigated area pH of precipitation is mainly under influence of pollution flowing from west and southern-west and local sources of its emission.

  6. Ensemble postprocessing for probabilistic quantitative precipitation forecasts

    Science.gov (United States)

    Bentzien, S.; Friederichs, P.

    2012-12-01

    Precipitation is one of the most difficult weather variables to predict in hydrometeorological applications. In order to assess the uncertainty inherent in deterministic numerical weather prediction (NWP), meteorological services around the globe develop ensemble prediction systems (EPS) based on high-resolution NWP systems. With non-hydrostatic model dynamics and without parameterization of deep moist convection, high-resolution NWP models are able to describe convective processes in more detail and provide more realistic mesoscale structures. However, precipitation forecasts are still affected by displacement errors, systematic biases and fast error growth on small scales. Probabilistic guidance can be achieved from an ensemble setup which accounts for model error and uncertainty of initial and boundary conditions. The German Meteorological Service (Deutscher Wetterdienst, DWD) provides such an ensemble system based on the German-focused limited-area model COSMO-DE. With a horizontal grid-spacing of 2.8 km, COSMO-DE is the convection-permitting high-resolution part of the operational model chain at DWD. The COSMO-DE-EPS consists of 20 realizations of COSMO-DE, driven by initial and boundary conditions derived from 4 global models and 5 perturbations of model physics. Ensemble systems like COSMO-DE-EPS are often limited with respect to ensemble size due to the immense computational costs. As a consequence, they can be biased and exhibit insufficient ensemble spread, and probabilistic forecasts may be not well calibrated. In this study, probabilistic quantitative precipitation forecasts are derived from COSMO-DE-EPS and evaluated at more than 1000 rain gauges located all over Germany. COSMO-DE-EPS is a frequently updated ensemble system, initialized 8 times a day. We use the time-lagged approach to inexpensively increase ensemble spread, which results in more reliable forecasts especially for extreme precipitation events. Moreover, we will show that statistical

  7. Organizational and economic parameters of resource provision of medical organizations

    Directory of Open Access Journals (Sweden)

    Aranovich L.M

    2014-03-01

    Full Text Available The aim of the research is to determine the main patterns of activity of in-patient medical organizations according to the resource provision of medical and diagnostic process. Material and methods. 20 medical organizations, including regional organizations, central regional hospitals, Saratov municipal health care organizations, non-private and private medical organizations have been surveyed. The survey of 60 chemists of hospital pharmacies has been conducted. Results. The analysis of the survey has showed the resource provision of medical and diagnostic process by medical products, the degree of technological provision in hospitals of various types and stated the main problems of activity on resource provision. Conclusion. It has been found out that the current medical provision with medical products is connected with the action of considerable number of objective and subjective factors and it defines the efficiency of medical social activity.

  8. Provision of neuropsychiatry services: variability and unmet need.

    Science.gov (United States)

    Agrawal, Niruj; Bhattacharya, Rahul; Rickards, Hugh

    2015-12-01

    Aims and method Neuropsychiatry services remain underdeveloped and underprovided. Previous studies have shown variability in service provision in the UK. In this survey we approached all mental health and neuropsychiatric service providers within London to map current neuropsychiatric service provision and explore perceived barriers. Results All the specialist mental health service providers responded. There was huge variability in neuropsychiatric service provision within different parts of London. There was evidence of significant unmet need and variability in service pathways. Lack of earmarked funds for neuropsychiatry and disjointed funding stream for such services were identified by providers as a barrier. Clinical implications This study provides further evidence of an ongoing lack of adequate neuropsychiatric service provision. Reasons for variability and unmet need are discussed. Adoption of a previously proposed hub-and-spoke model of service provision and the removal of commissioning barriers through uniform national commissioning may help deal with this problem. PMID:26755990

  9. 40 CFR 420.90 - Applicability; description of the acid pickling subcategory.

    Science.gov (United States)

    2010-07-01

    ... pickling subcategory. 420.90 Section 420.90 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Pickling Subcategory § 420.90 Applicability; description of the acid pickling subcategory. The provisions... owned treatment works resulting from sulfuric acid, hydrochloric acid, or combination acid...

  10. Quantitative analysis of Bordeaux red wine precipitates by solid-state NMR: Role of tartrates and polyphenols.

    Science.gov (United States)

    Prakash, Shipra; Iturmendi, Nerea; Grelard, Axelle; Moine, Virginie; Dufourc, Erick

    2016-05-15

    Stability of wines is of great importance in oenology matters. Quantitative estimation of dark red precipitates formed in Merlot and Cabernet Sauvignon wine from Bordeaux region for vintages 2012 and 2013 was performed during the oak barrel ageing process. Precipitates were obtained by placing wine at -4°C or 4°C for 2-6 days and monitored by periodic sampling during a one-year period. Spectroscopic identification of the main families of components present in the precipitate powder was performed with (13)C solid-state CPMAS NMR and 1D and 2D solution NMR of partially water re-solubilized precipitates. The study revealed that the amount of precipitate obtained is dependent on vintage, temperature and grape variety. Major components identified include potassium bitartrate, polyphenols, polysaccharides, organic acids and free amino acids. No evidence was found for the presence of proteins. The influence of main compounds found in the precipitates is discussed in relation to wine stability.

  11. Predictably Philandering Females Prompt Poor Paternal Provisioning.

    Science.gov (United States)

    Schroeder, Julia; Hsu, Yu-Hsun; Winney, Isabel; Simons, Mirre; Nakagawa, Shinichi; Burke, Terry

    2016-08-01

    One predicted cost of female infidelity in socially monogamous species is that cuckolded males should provide less parental care. This relationship is robust across species, but evidence is ambiguous within species. We do not know whether individual males reduce their care when paired with cheating females compared with when paired with faithful females (within-male adjustment) or, alternatively, if the males that pair with cheating females are the same males that provide less parental care in general (between-male effect). Our exceptionally extensive long-term data set of repeated observations of a wild passerine allows us to disentangle paternal care adjustment within males-within pairs and between males-while accounting for environmental variables. We found a within-male adjustment of paternal provisioning, but not incubation effort, relative to the cuckoldry in their nest. This effect was mainly driven by females differing consistently in their fidelity. There was no evidence that this within-male adjustment also took place across broods with the same female, and we found no between-male effect. Interestingly, males that gained more extrapair paternity provided less care. Data from a cross-foster experiment suggested that males did not use kin recognition to assess paternity. Our results provide insight into the role of individual variation in parental care and mating systems. PMID:27420786

  12. Advance Resource Provisioning in Bulk Data Scheduling

    Energy Technology Data Exchange (ETDEWEB)

    Balman, Mehmet

    2012-10-01

    Today?s scientific and business applications generate mas- sive data sets that need to be transferred to remote sites for sharing, processing, and long term storage. Because of increasing data volumes and enhancement in current net- work technology that provide on-demand high-speed data access between collaborating institutions, data handling and scheduling problems have reached a new scale. In this paper, we present a new data scheduling model with ad- vance resource provisioning, in which data movement operations are defined with earliest start and latest comple- tion times. We analyze time-dependent resource assign- ment problem, and propose a new methodology to improve the current systems by allowing researchers and higher-level meta-schedulers to use data-placement as-a-service, so they can plan ahead and submit transfer requests in advance. In general, scheduling with time and resource conflicts is NP-hard. We introduce an efficient algorithm to organize multiple requests on the fly, while satisfying users? time and resource constraints. We successfully tested our algorithm in a simple benchmark simulator that we have developed, and demonstrated its performance with initial test results.

  13. PENSIONS PROVISION IN SOCIAL SYSTEMS OF COUNTRIES

    Directory of Open Access Journals (Sweden)

    Rievajová Eva

    2013-12-01

    Full Text Available Special attention in all European countries is given to issues of social security of persons in retirement age. Pension systems represent the basic part of the social model of each country which reached a certain level of development. Thus pension systems have a great impact on living standards of large part of population and hence its consumption and have a large impact on functioning of the whole economy of a nation state. A serious problem at present is to achieve a balance between contributions to pension system and entitlements provided to citizens of retirement age, the ratio between the number of employed in the economy and the number of beneficiaries. Setting up and functioning of the pension system depends on many factors, besides demographic trends it is also the development of economy and state of public finances. Therefore, they are going through an ongoing process of reforms adapting economic, social and political situation in each particular country. The aim of this paper is to characterize the social security from the perspective of various approaches to this issue with an emphasis on pension provision as the most discussed and costliest part of the social insurance system and social security schemes of a society. It also pointed out the basic problems of the current pension scheme worldwide and approaches to its modernization.

  14. The provision of radiological protection services

    International Nuclear Information System (INIS)

    This publication is a code of practice for the provision or radiological protection services for establishments in which, or in part of which, work is primarily with radiation sources. It was prepared with the help of an international panel of experts and representatives of international organizations which have an interest in this field and was promulgated by the Director General of the Agency under the authority of the Board of Governors of the Agency as a code of practice in the framework of the Agency's Safety Standards. The Board of Governors also authorized the Director General to recommend to Member States that the code of practice be taken into account in the formulation of national regulations or recommendations. The Appendix to the code contains a number of examples of the organization of radiological protection services that have been provided by the members of the panel of experts. These examples do not form a part of the code of practice, but are intended to illustrate the methods of organization which have been adopted in different countries.

  15. Role of precipitation chemistry versus other watershed properties in Wisconsin Lake acidification

    Energy Technology Data Exchange (ETDEWEB)

    Loucks, O.L.; Glass, G.E.; Sorensen, J.A.; Liukkonen, B.W.; Allert, J.

    1986-01-01

    Data for over 100 watershed properties, including aspects of topography, hydrology, geology, soils, vegetation, lake morphometry, and input precipitation chemistry were developed since 1980 for 316 watersheds in northern Wisconsin. The hypothesis being evaluated for this lake population is that the observed water chemistry can be accounted for as a function of antecedent water and chemical inputs, after considering exchange processes in the lake and watershed and the lake/groundwater interactions. Observed variability in color, sulfate, and acid-neutralizing-capacity levels in Wisconsin lakes were explained. The results differ from previous studies in Wisconsin and nearby areas of Michigan and Minnesota by indicating that in some lakes acidity may not be in equilibrium with current precipitation chemistry.

  16. PRECIPITATION-REGULATED STAR FORMATION IN GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Voit, G. Mark; O’Shea, Brian W.; Donahue, Megan [Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States); Bryan, Greg L., E-mail: voit@pa.msu.edu [Department of Astronomy, Columbia University, New York, NY (United States)

    2015-07-20

    Galaxy growth depends critically on the interplay between radiative cooling of cosmic gas and the resulting energetic feedback that cooling triggers. This interplay has proven exceedingly difficult to model, even with large supercomputer simulations, because of its complexity. Nevertheless, real galaxies are observed to obey simple scaling relations among their primary observable characteristics. Here we show that a generic emergent property of the interplay between cooling and feedback can explain the observed scaling relationships between a galaxy's stellar mass, its total mass, and its chemical enrichment level, as well as the relationship between the average orbital velocity of its stars and the mass of its central black hole. These relationships naturally result from any feedback mechanism that strongly heats a galaxy's circumgalactic gas in response to precipitation of colder clouds out of that gas, because feedback then suspends the gas in a marginally precipitating state.

  17. Thyroid Storm Precipitated by Duodenal Ulcer Perforation

    Directory of Open Access Journals (Sweden)

    Shoko Natsuda

    2015-01-01

    Full Text Available Thyroid storm is a rare and life-threatening complication of thyrotoxicosis that requires prompt treatment. Thyroid storm is also known to be associated with precipitating events. The simultaneous treatment of thyroid storm and its precipitant, when they are recognized, in a patient is recommended; otherwise such disorders, including thyroid storm, can exacerbate each other. Here we report the case of a thyroid storm patient (a 55-year-old Japanese male complicated with a perforated duodenal ulcer. The patient was successfully treated with intensive treatment for thyroid storm and a prompt operation. Although it is believed that peptic ulcer rarely coexists with hyperthyroidism, among patients with thyroid storm, perforation of a peptic ulcer has been reported as one of the causes of fatal outcome. We determined that surgical intervention was required in this patient, reported despite ongoing severe thyrotoxicosis, and reported herein a successful outcome.

  18. 42 CFR 426.500 - Procedure for filing an acceptable complaint concerning a provision (or provisions) of an NCD.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Procedure for filing an acceptable complaint concerning a provision (or provisions) of an NCD. 426.500 Section 426.500 Public Health CENTERS FOR MEDICARE... Food and Drug Administration in relation to that drug or device. (d) Joint complaints—(1)...

  19. Scale Interaction in a California precipitation event

    Energy Technology Data Exchange (ETDEWEB)

    Leach, M. J., LLNL

    1997-09-01

    Heavy rains and severe flooding frequently plaque California. The heavy rains are most often associated with large scale cyclonic and frontal systems, where large scale dynamics and large moisture influx from the tropical Pacific interact. however, the complex topography along the west coast also interacts with the large scale influences, producing local areas with heavier precipitation. In this paper, we look at some of the local interactions with the large scale.

  20. Analysis of microalloy precipitate reversion in steels

    Science.gov (United States)

    Michal, G. M.; Locci, I. E.

    1988-01-01

    The influence of the ferrite to austenite allotropic transformation on the stability of MXn precipitates in an iron matrix is studied. In the MX phase, M is a group IVb or Vb transition metal, such as niobium, titanium, or vanadium. X is carbon or nitrogen and n is in the range of 0.75-1.0. The application of the present model to the case of vanadium carbide reversion in a microalloyed steel is discussed.

  1. The Precipitation Characteristics of ISCCP Tropical Weather States

    Science.gov (United States)

    Lee, Dongmin; Oreopoulos, Lazaros; Huffman, George J.; Rossow, William B.; Kang, In-Sik

    2011-01-01

    We examine the daytime precipitation characteristics of the International Satellite Cloud Climatology Project (ISCCP) weather states in the extended tropics (35 deg S to 35 deg N) for a 10-year period. Our main precipitation data set is the TRMM Multisatellite Precipitation Analysis 3B42 data set, but Global Precipitation Climatology Project daily data are also used for comparison. We find that the most convective weather state (WS1), despite an occurrence frequency below 10%, is the most dominant state with regard to surface precipitation, producing both the largest mean precipitation rates when present and the largest percent contribution to the total precipitation of the tropical zone of our study; yet, even this weather state appears to not precipitate about half the time. WS1 exhibits a modest annual cycle of domain-average precipitation rate, but notable seasonal shifts in its geographic distribution. The precipitation rates of the other weather states tend to be stronger when occurring before or after WS1. The relative contribution of the various weather states to total precipitation is different between ocean and land, with WS1 producing more intense precipitation on average over ocean than land. The results of this study, in addition to advancing our understanding of the current state of tropical precipitation, can serve as a higher order diagnostic test on whether it is distributed realistically among different weather states in atmospheric models.

  2. Precipitation sensitivity to warming estimated from long island records

    Science.gov (United States)

    Polson, D.; Hegerl, G. C.; Solomon, S.

    2016-07-01

    Some of the most damaging impacts of climate change are a consequence of changes to the global water cycle. Atmospheric warming causes the water cycle to intensify, increasing both atmospheric water vapor concentrations and global precipitation and enhancing existing patterns of precipitation minus evaporation (P ‑ E). This relationship between temperature and precipitation therefore makes understanding how precipitation has changed with global temperatures in the past crucial for projecting changes with future warming. In situ observations cannot readily estimate global precipitation sensitivity to temperature (dP/dT), as land precipitation changes are affected by water limitation. Satellite observations of precipitation over ocean are only available after 1979, but studies based on them suggest a precipitation sensitivity over wet tropical (30N–30S) oceans that exceeds the Clausius–Clapeyron value. Here, we determine for the first time precipitation sensitivity using longer (1930–2005), island-based in situ observations to estimate dP/dT over islands. The records show a robust pattern of increasing precipitation in the tropics and decreasing precipitation in the subtropics, as predicted from physical arguments, and heavy precipitation shows a stronger sensitivity than mean precipitation over many islands. The pattern and magnitude of island-based dP/dT agree with climate models if masked to island locations, supporting model predictions of future changes.

  3. Intensity-dependent parameterization of elevation effects in precipitation analysis

    Directory of Open Access Journals (Sweden)

    T. Haiden

    2009-03-01

    Full Text Available Elevation effects in long-term (monthly to inter-annual precipitation data have been widely studied and are taken into account in the regionalization of point-like precipitation amounts by using methods like external drift kriging and cokriging. On the daily or hourly time scale, precipitation-elevation gradients are more variable, and difficult to parameterize. For example, application of the annual relative precipitation-elevation gradient to each 12-h sub-period reproduces the annual total, but at the cost of a large root-mean-square error. If the precipitation-elevation gradient is parameterized as a function of precipitation rate, the error can be substantially reduced. It is shown that the form of the parameterization suggested by the observations conforms to what one would expect based on the physics of the orographic precipitation process (the seeder-feeder mechanism. At low precipitation rates, orographic precipitation is "conversion-limited", thus increasing roughly linearly with precipitation rate. At higher rates, orographic precipitation becomes "condensation-limited" thus leading to an additive rather than multiplicative orographic precipitation enhancement. Also it is found that for large elevation differences it becomes increasingly important to take into account those events where the mountain station receives precipitation but the valley station remains dry.

  4. Global warming without global mean precipitation increase?

    Science.gov (United States)

    Salzmann, Marc

    2016-01-01

    Global climate models simulate a robust increase of global mean precipitation of about 1.5 to 2% per kelvin surface warming in response to greenhouse gas (GHG) forcing. Here, it is shown that the sensitivity to aerosol cooling is robust as well, albeit roughly twice as large. This larger sensitivity is consistent with energy budget arguments. At the same time, it is still considerably lower than the 6.5 to 7% K−1 decrease of the water vapor concentration with cooling from anthropogenic aerosol because the water vapor radiative feedback lowers the hydrological sensitivity to anthropogenic forcings. When GHG and aerosol forcings are combined, the climate models with a realistic 20th century warming indicate that the global mean precipitation increase due to GHG warming has, until recently, been completely masked by aerosol drying. This explains the apparent lack of sensitivity of the global mean precipitation to the net global warming recently found in observations. As the importance of GHG warming increases in the future, a clear signal will emerge. PMID:27386558

  5. A subgrid parameterization scheme for precipitation

    Directory of Open Access Journals (Sweden)

    S. Turner

    2011-07-01

    Full Text Available With increasing computing power, the horizontal resolution of numerical weather prediction (NWP models is improving and today reaches 1 to 5 km. Nevertheless, clouds and precipitation are still subgrid scale processes for most cloud types, such as cumulus and stratocumulus. Subgrid scale parameterizations for water vapor condensation have been in use for many years and are based on a prescribed PDF of relative humidity spatial variability within the grid, thus providing a diagnosis of the cloud fraction. A similar scheme is developed and tested here. It is based on a prescribed PDF of cloud water variability and a threshold value of liquid water content for droplet collection to derive a rain fraction within the model grid. Precipitation of rainwater raises additional concerns relative to the overlap of cloud and rain fractions, however. The scheme is developed following an analysis of data collected during field campaigns in stratocumulus (DYCOMS-II and fair weather cumulus (RICO and tested in a 1-D framework against large eddy simulations of these observed cases. The new parameterization is then implemented in a 3-D NWP model with a horizontal resolution of 2.5 km to simulate real cases of precipitating cloud systems over France.

  6. How extreme is extreme hourly precipitation?

    Science.gov (United States)

    Papalexiou, Simon Michael; Dialynas, Yannis G.; Pappas, Christoforos

    2016-04-01

    The importance of accurate representation of precipitation at fine time scales (e.g., hourly), directly associated with flash flood events, is crucial in hydrological design and prediction. The upper part of a probability distribution, known as the distribution tail, determines the behavior of extreme events. In general, and loosely speaking, tails can be categorized in two families: the subexponential and the hyperexponential family, with the first generating more intense and more frequent extremes compared to the latter. In past studies, the focus has been mainly on daily precipitation, with the Gamma distribution being the most popular model. Here, we investigate the behaviour of tails of hourly precipitation by comparing the upper part of empirical distributions of thousands of records with three general types of tails corresponding to the Pareto, Lognormal, and Weibull distributions. Specifically, we use thousands of hourly rainfall records from all over the USA. The analysis indicates that heavier-tailed distributions describe better the observed hourly rainfall extremes in comparison to lighter tails. Traditional representations of the marginal distribution of hourly rainfall may significantly deviate from observed behaviours of extremes, with direct implications on hydroclimatic variables modelling and engineering design.

  7. A subgrid parameterization scheme for precipitation

    Directory of Open Access Journals (Sweden)

    S. Turner

    2012-04-01

    Full Text Available With increasing computing power, the horizontal resolution of numerical weather prediction (NWP models is improving and today reaches 1 to 5 km. Nevertheless, clouds and precipitation formation are still subgrid scale processes for most cloud types, such as cumulus and stratocumulus. Subgrid scale parameterizations for water vapor condensation have been in use for many years and are based on a prescribed probability density function (PDF of relative humidity spatial variability within the model grid box, thus providing a diagnosis of the cloud fraction. A similar scheme is developed and tested here. It is based on a prescribed PDF of cloud water variability and a threshold value of liquid water content for droplet collection to derive a rain fraction within the model grid. Precipitation of rainwater raises additional concerns relative to the overlap of cloud and rain fractions, however. The scheme is developed following an analysis of data collected during field campaigns in stratocumulus (DYCOMS-II and fair weather cumulus (RICO and tested in a 1-D framework against large eddy simulations of these observed cases. The new parameterization is then implemented in a 3-D NWP model with a horizontal resolution of 2.5 km to simulate real cases of precipitating cloud systems over France.

  8. Hydrologic information server for benchmark precipitation dataset

    Science.gov (United States)

    McEnery, John A.; McKee, Paul W.; Shelton, Gregory P.; Ramsey, Ryan W.

    2013-01-01

    This paper will present the methodology and overall system development by which a benchmark dataset of precipitation information has been made available. Rainfall is the primary driver of the hydrologic cycle. High quality precipitation data is vital for hydrologic models, hydrometeorologic studies and climate analysis,and hydrologic time series observations are important to many water resources applications. Over the past two decades, with the advent of NEXRAD radar, science to measure and record rainfall has improved dramatically. However, much existing data has not been readily available for public access or transferable among the agricultural, engineering and scientific communities. This project takes advantage of the existing CUAHSI Hydrologic Information System ODM model and tools to bridge the gap between data storage and data access, providing an accepted standard interface for internet access to the largest time-series dataset of NEXRAD precipitation data ever assembled. This research effort has produced an operational data system to ingest, transform, load and then serve one of most important hydrologic variable sets.

  9. Global warming without global mean precipitation increase?

    Science.gov (United States)

    Salzmann, Marc

    2016-06-01

    Global climate models simulate a robust increase of global mean precipitation of about 1.5 to 2% per kelvin surface warming in response to greenhouse gas (GHG) forcing. Here, it is shown that the sensitivity to aerosol cooling is robust as well, albeit roughly twice as large. This larger sensitivity is consistent with energy budget arguments. At the same time, it is still considerably lower than the 6.5 to 7% K(-1) decrease of the water vapor concentration with cooling from anthropogenic aerosol because the water vapor radiative feedback lowers the hydrological sensitivity to anthropogenic forcings. When GHG and aerosol forcings are combined, the climate models with a realistic 20th century warming indicate that the global mean precipitation increase due to GHG warming has, until recently, been completely masked by aerosol drying. This explains the apparent lack of sensitivity of the global mean precipitation to the net global warming recently found in observations. As the importance of GHG warming increases in the future, a clear signal will emerge.

  10. Global warming without global mean precipitation increase?

    Science.gov (United States)

    Salzmann, Marc

    2016-06-01

    Global climate models simulate a robust increase of global mean precipitation of about 1.5 to 2% per kelvin surface warming in response to greenhouse gas (GHG) forcing. Here, it is shown that the sensitivity to aerosol cooling is robust as well, albeit roughly twice as large. This larger sensitivity is consistent with energy budget arguments. At the same time, it is still considerably lower than the 6.5 to 7% K(-1) decrease of the water vapor concentration with cooling from anthropogenic aerosol because the water vapor radiative feedback lowers the hydrological sensitivity to anthropogenic forcings. When GHG and aerosol forcings are combined, the climate models with a realistic 20th century warming indicate that the global mean precipitation increase due to GHG warming has, until recently, been completely masked by aerosol drying. This explains the apparent lack of sensitivity of the global mean precipitation to the net global warming recently found in observations. As the importance of GHG warming increases in the future, a clear signal will emerge. PMID:27386558

  11. 7 CFR 457.148 - Fresh market pepper crop insurance provisions.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Fresh market pepper crop insurance provisions. 457.148... pepper crop insurance provisions. The fresh market pepper crop insurance provisions for the 1999 and... Fresh Market Pepper Crop Provisions If a conflict exists among the policy provisions, the order...

  12. Microscopic modelling of simultaneous two-phase precipitation: application to carbide precipitation in low-carbon steels

    International Nuclear Information System (INIS)

    A thermodynamically-based precipitation model, employing the classical nucleation and growth theories, has been adapted to deal with simultaneous precipitation of metastable and stable phases. This model gives an estimation of the precipitation kinetics (time evolution of radius and density of precipitates for both phases, as well as the evolution of solute fraction) in a wide range of temperature. Results were successfully compared with an experimental isothermal precipitation diagram (Time-Temperature-Transformation, TTT) from the literature for the precipitation of ε carbide and Fe3C in low-carbon steels

  13. Congruence of appropriation and provision in collective water provision in Central Namibia

    Directory of Open Access Journals (Sweden)

    Thomas Falk

    2016-02-01

    Full Text Available Achieving cooperation in natural resource management is always a challenge when incentives exist for an individual to maximise her short term benefits at the cost of a group. We study a public good social dilemma in water infrastructure provision on land reform farms in Namibia. In the context of the Namibian land reform, arbitrarily mixed groups of livestock farmers have to share the operation and maintenance of water infrastructure. Typically, water is mainly used for livestock production, and livestock numbers are subject to high fluctuations due to the given environmental conditions. Our paper assesses how alternative payment systems with differing congruence of provision and appropriation support the cooperation in the group given the ever-changing equilibria. In a first step, we conducted an exploratory overview of the social-ecological system of central Namibian land reform projects. The Social Ecological System (SES Framework served as a guideline for this assessment (Ostrom 2009. Taking the complexity of the cooperation situation into account, in the second step we designed a role-play that is based on a social-ecological simulation model. The role-play simulates the real-life decision situations of land reform beneficiaries wherein equilibria are permanently changing. This approach helped us to not only better understand the cooperation challenges of Namibian land reform beneficiaries, but also supported stakeholders in their decision making and institution building. Our study provides evidence to support that land reform beneficiaries increase their contributions as they own more livestock and as other group members increase their payments. Nevertheless, only groups with relatively homogeneous livestock endowments manage to agree on payment rules. Interestingly, the dominant rule is an “equal payment per farmer” and not a “payment per head of livestock”, though the latter would imply a higher congruence of provision and

  14. Precipitation products from the hydrology SAF

    Directory of Open Access Journals (Sweden)

    A. Mugnai

    2013-08-01

    Full Text Available The EUMETSAT Satellite Application Facility on Support to Operational Hydrology and Water Management (H-SAF was established by the EUMETSAT Council on 3 July 2005, starting activity on 1 September 2005. The Italian Meteorological Service serves as Leading Entity on behalf of twelve European member countries. H-SAF products include precipitation, soil moisture and snow parameters. Some products are based only on satellite observations, while other products are based on the assimilation of satellite measurements/products into numerical models. In addition to product development and generation, H-SAF includes a product validation program and a hydrological validation program that are coordinated, respectively, by the Italian Department of Civil Protection and by the Polish Institute of Meteorology and Water Management. The National Center of Aeronautical Meteorology and Climatology (CNMCA of the Italian Air Force is responsible for operational product generation and dissemination. In this paper we describe the H-SAF precipitation algorithms and products, which have been developed by the Italian Institute of Atmospheric Sciences and Climate (in collaboration with the international community and by CNMCA during the Development Phase (DP, 2005–2010 and the first Continuous Development and Operations Phase (CDOP-1, 2010–2012. The precipitation products are based on passive microwave measurements obtained from radiometers onboard different sun-synchronous low-Earth-orbiting satellites (especially, the SSM/I and SSMIS radiometers onboard DMSP satellites and the AMSU-A + AMSU-B/MHS radiometer suites onboard EPS-MetOp and NOAA-POES satellites, as well as on combined infrared/passive microwave measurements in which the passive microwave precipitation estimates are used in conjunction with SEVIRI images from the geostationary MSG satellite. Moreover, the H-SAF product generation and dissemination chain and independent product validation activities are

  15. Trend analysis of precipitation in Jharkhand State, India - Investigating precipitation variability in Jharkhand State

    Science.gov (United States)

    Chandniha, Surendra Kumar; Meshram, Sarita Gajbhiye; Adamowski, Jan Franklin; Meshram, Chandrashekhar

    2016-08-01

    Jharkhand is one of the eastern states of India which has an agriculture-based economy. Uncertain and erratic distribution of precipitation as well as a lack of state water resources planning is the major limitation to crop growth in the region. In this study, the spatial and temporal variability in precipitation in the state was examined using a monthly precipitation time series of 111 years (1901-2011) from 18 meteorological stations. Autocorrelation and Mann-Kendall/modified Mann-Kendall tests were utilized to detect possible trends, and the Theil and Sen slope estimator test was used to determine the magnitude of change over the entire time series. The most probable change year (change point) was detected using the Pettitt-Mann-Whitney test, and the entire time series was sub-divided into two parts: before and after the change point. Arc-Map 9.3 software was utilized to assess the spatial patterns of the trends over the entire state. Annual precipitation exhibited a decreasing trend in 5 out of 18 stations during the whole period. For annual, monsoon and winter periods of precipitation, the slope test indicated a decreasing trend for all stations during 1901-2011. The highest variability was observed in post-monsoon precipitation (77.87 %) and the lowest variability was observed in the annual series (15.76 %) over the 111 years. An increasing trend in precipitation in the state was found during the period 1901-1949, which was reversed during the subsequent period (1950-2011).

  16. Restructuring the Schoolbook Provision System in Indonesia

    Directory of Open Access Journals (Sweden)

    Dedi Supriadi

    1999-03-01

    Full Text Available Schoolbooks account for between 65% and 75% of all publishing activity in Indonesia. The amount of money allocated is continually increasing. Priority is given to the primary and junior secondary school levels (6+3 years, which are compulsory. Between 1969 and 1988, the Government of Indonesia (GOI has produced some 550 million primary textbooks and library books. Up to the year 2000, the GOI has decided to allocate the total of US$ 355.2 million to produce 250 million copies of primary and junior secondary school textbooks to reach the ratio of one book for each student. In addition, around Rp 20-50 billion (US$ 10-20 million annually is spent to purchase 8-17 million copies of reading books which are aimed at stimulating the reading interest of primary school children. These books are distributed free to some 168,000 primary and 26,969 junior secondary schools throughout Indonesia. Following the massive efforts to increase book availability at schools, some innovative policies are being taken. Book evaluation standards have been improved to ensure that only high quality books are used at schools. The distribution system has been restructured to guarantee that books reach targeted schools. Consequently, the book monitoring system has had to be strengthened to examine whether or not the books really reach the schools and are used properly by students and teachers in the classrooms. In the last three years, there has also been a growing concern with multicultural issues in schoolbook provision programs. In such a culturally diverse nation as Indonesia, schoolbooks should also be culturally sensitive and be recognize the varied sociocultural backgrounds which affect students' learning.

  17. Cintichem modified process - {sup 99}Mo precipitation step: application of statistical analysis tools over the reaction parameters

    Energy Technology Data Exchange (ETDEWEB)

    Teodoro, Rodrigo; Dias, Carla R.B.R.; Osso Junior, Joao A., E-mail: jaosso@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Fernandez Nunez, Eutimio Gustavo [Universidade de Sao Paulo (EP/USP), SP (Brazil). Escola Politecnica. Dept. de Engenharia Quimica

    2011-07-01

    Precipitation of {sup 99}Mo by {alpha}-benzoin oxime ({alpha}-Bz) is a standard precipitation method for molybdenum due the high selectivity of this agent. Nowadays, statistical analysis tools have been employed in analytical systems to prove its efficiency and feasibility. IPEN has a project aiming the production of {sup 99}Mo by the fission of {sup 235}U route. The processing uses as the first step the precipitation of {sup 99}Mo with {alpha}-Bz. This precipitation step involves many key reaction parameters. The aim of this work is based on the development of the already known acidic route to produce {sup 99}Mo as well as the optimization of the reactional parameters applying statistical tools. In order to simulate {sup 99}Mo precipitation, the study was conducted in acidic media using HNO{sub 3}, {alpha}Bz as precipitant agent and NaOH /1%H{sub 2}O{sub 2} as dissolver solution. Then, a Mo carrier, KMnO{sub 4} solutions and {sup 99}Mo tracer were added to the reaction flask. The reactional parameters ({alpha}-Bz/Mo ratio, Mo carrier, reaction time and temperature, and cooling reaction time before filtration) were evaluated under a fractional factorial design of resolution V. The best values of each reactional parameter were determined by a response surface statistical planning. The precipitation and recovery yields of {sup 99}Mo were measured using HPGe detector. Statistical analysis from experimental data suggested that the reactional parameters {alpha}-Bz/Mo ratio, reaction time and temperature have a significant impact on {sup 99}Mo precipitation. Optimization statistical planning showed that higher {alpha}Bz/Mo ratios, room temperature, and lower reaction time lead to higher {sup 99}Mo yields. (author)

  18. Climate Prediction Center(CPC)Daily GOES Precipitation Index (GPI)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — GOES Precipitation Index (GPI) is a precipitation estimation algorithm. The GPI technique estimates tropical rainfall using cloud-top temperature as the sole...

  19. A study on strategic provisioning of cloud computing services.

    Science.gov (United States)

    Whaiduzzaman, Md; Haque, Mohammad Nazmul; Rejaul Karim Chowdhury, Md; Gani, Abdullah

    2014-01-01

    Cloud computing is currently emerging as an ever-changing, growing paradigm that models "everything-as-a-service." Virtualised physical resources, infrastructure, and applications are supplied by service provisioning in the cloud. The evolution in the adoption of cloud computing is driven by clear and distinct promising features for both cloud users and cloud providers. However, the increasing number of cloud providers and the variety of service offerings have made it difficult for the customers to choose the best services. By employing successful service provisioning, the essential services required by customers, such as agility and availability, pricing, security and trust, and user metrics can be guaranteed by service provisioning. Hence, continuous service provisioning that satisfies the user requirements is a mandatory feature for the cloud user and vitally important in cloud computing service offerings. Therefore, we aim to review the state-of-the-art service provisioning objectives, essential services, topologies, user requirements, necessary metrics, and pricing mechanisms. We synthesize and summarize different provision techniques, approaches, and models through a comprehensive literature review. A thematic taxonomy of cloud service provisioning is presented after the systematic review. Finally, future research directions and open research issues are identified.

  20. A Study on Strategic Provisioning of Cloud Computing Services

    Directory of Open Access Journals (Sweden)

    Md Whaiduzzaman

    2014-01-01

    Full Text Available Cloud computing is currently emerging as an ever-changing, growing paradigm that models “everything-as-a-service.” Virtualised physical resources, infrastructure, and applications are supplied by service provisioning in the cloud. The evolution in the adoption of cloud computing is driven by clear and distinct promising features for both cloud users and cloud providers. However, the increasing number of cloud providers and the variety of service offerings have made it difficult for the customers to choose the best services. By employing successful service provisioning, the essential services required by customers, such as agility and availability, pricing, security and trust, and user metrics can be guaranteed by service provisioning. Hence, continuous service provisioning that satisfies the user requirements is a mandatory feature for the cloud user and vitally important in cloud computing service offerings. Therefore, we aim to review the state-of-the-art service provisioning objectives, essential services, topologies, user requirements, necessary metrics, and pricing mechanisms. We synthesize and summarize different provision techniques, approaches, and models through a comprehensive literature review. A thematic taxonomy of cloud service provisioning is presented after the systematic review. Finally, future research directions and open research issues are identified.