Chlorine is widely used in drinking water disinfection due to be a powerful and not expense disinfection. Although the benefits of disinfection, the formation of stable disinfection by-products of the health concern, is the result of the interaction of aqueous chlorine with natural organic matter presents in water. Disinfection by-products generated in major concentration are trihalomethane and haloacetic acids. Disinfection by-products generated in minor concentration are haloacetonitriles, haloketones,chloral hydrate and chloropicrin and some new groups such as cyanogen halides and trihaloacetaldydes. In this work two analytical methods.: headspace/gas chromatography/electron capture detector and liquid-liquid microextraction/gas chromatography/electron capture detector are studied and compared to determine the minor ...
THMs are disinfection by-products (DBPs) generated during waterchlorination. Concentration of individual and total THMs, depends on treatment process and THMs precursors level. ATLL water utility has two DWTP (Llobregar and Ter) that produce and supply drinking water to Barcelona and regional area. This work studies the levels of THMs along the ATLL distribution system (450 km). Although, no differences were observed along water pipes system, changes of water resource and mix procedures were related. (Author) 12 refs.
Chloromethane, dichloromethane and 1,2-dichloroethane were completely decomposed in air on perovskite-type catalysts (LaMnO{sub 3}, LaCoO{sub 3}, (La{sub 0.84},Sr{sub 0.16})(Mn{sub 0.67},Co{sub 0.33})O{sub 3}) at reaction temperatures above 550C. Besides the main reaction products (carbon dioxide, water and hydrochloric acid), by-products (higher chlorinated-, C-C coupling- and cracking products) were formed in the low temperature range. Depending on the reaction temperature, residence time and kind of chlorinated hydrocarbon a reversible catalyst deactivation takes place. In the case of LaCoO{sub 3} catalysts an irreversible deactivation was observed. X-ray diffraction (XRD) and electron probe microanalysis (EPMA) measurements with the perovskite-type catalysts after interaction of chlorinated hydrocarbons indicate the formation of chlorinated species on the ...
Humic acids are primarily a result of the microbiological degradation of surrounding vegetation and animal decay and enter surface waters through rain water run-off from the surrounding land. This often gives rise to large seasonal variations, high concentrations in the wet season and lower concentrations in the dry season. Alone humic acid is just a colour problem but when present in conventional treatment processes like chlorination, carcinogenic by-products like trihalomethane and haloacetic acid are formed. This, in addition to the demand for clean potable drinking water, has sparked extensive research into alternative processes for the production of drinking water from various natural/industrial sources. One of the major areas of focus in these studies is the use of membranes in micro...
Hundreds of organic byproducts of chlorination are now known to occur in drinking water along with the trihalomethanes. About twenty of these appear to be found with sufficient frequency and in sufficient concentration to attract consideration for regulations. These include chloral hydrate, chloropicrin, a trichloropropanone, haloacetonitriles, and haloacetic acids. Trihalomethane concentrations do not serve as good predictors of concentrations of these other byproducts because their conditions of formation vary widely. This is especially true when pH is changed. Treatment strategies for control of these byproducts including the trihalomethanes are: Remove the compounds after they are formed; Remove precursors; and Use other disinfectants. Current evidence supports the idea that precursor removal processes effective for trihalomethane control may be effective for the other byproducts as well.
Hydrologic processes in suburban watersheds and their effects on water quality warrant investigation. Biweekly and storm samples were collected and analyzed for base cations, selected anions, and DOC over a one-year period at the outlet of three small (37 - 55 ha) watersheds (one forested, two with different degrees of suburban development) in the Croton Watershed, southeastern New York. Less frequent sampling for Pt/Co color and disinfection by-product precursors (DBPs) were also conducted. Median baseflow concentrations (>3 days since rainfall) of DOC were similar, ranging from 2.1 to 1.8 to 1.7 mg L -1 for the most urbanized to the forested watershed, respectively. On a unit area load basis (kg ha-1 yr-1), the range was from 8.9 to 6.4 to 5.1, again from most urbanized to forested watershed. All three watersheds showed similar storm responses, with evidence for a flushing mechanism in that DOC concentration increased with increasing ...
Data on raw water quality, disinfection treatment practices, and the resulting mutagenic properties of the treated water were compiled from pilot- and full-scale treatment experiments to evaluate that...Full Text Available
The activated charcoal is very appreciates for the water treatment. It do not generate by-product of treatment. In return it is saturated after some time and may releases pollutant compounds. When and how to get to its regeneration?.
The global problem concerning contamination of the environment because of human activities is increasing. Most of the environmental contaminants are chemical by-products and heavy metals such as lead (Pb). Lead released into the environment makes its way into the air, soil and water. Lead contribute...
The effects of freeze-thaw cycling on the strength and durability of samples of compacted, stabilized, wet flue gas desulfurization (FGD) by-products are reported. The results of laboratory tests show a clear relationship between higher water contents and...
The solar array wings were deployed by swinging two half-blanket boxes open from a folded hinge launch position .... pure-waterby-product of the shuttle's fuel cell power generators because ..... outgassing limits, flammability limits, ... Foale fills a water microbiology bag for in-flight analysis. ...
Treatment of coal or coconut shell activated carbons with either phosgene or chlorine at 180{degree}C followed by washing with methanol or water results in chlorinated carbons with very similar pore structures to their precursors. Water adsorption experiments show that the modified materials are relatively hydrophobic, presumably as a result of replacement of oxygen-containing surface groups by chlorine. Adsorption of the model hydrophobic vapour chloropicrin from humid air is usually better for the modified carbons which, unlike the controls, do not appear to be subject to degradation in performance on ageing in a humid atmosphere. The stability of the modified carbons is probably a consequence of the chlorination of those sites on the control carbons that are prone to ready oxidation or hydroxylation. 1 tab., 2 figs., 17 refs.
Deregulation of the electric power industry in Alberta holds the prospect of providing greater choice for customers. One such option will be `green power` which is provided by renewable energy technologies. The energy produced would be without environmental impacts such as air emissions, water pollution, flooding, thermal emissions or waste by-products. Wind power, small scale hydro power, photovoltaics and biomass technologies have been termed as `green power`. The choices that customers make will not be focused on price alone. Market forces are emerging to demand reduction in emissions which will result in a market for `green energy` products and facilitate achieving goals for a sustainable future.
Chlorination of water can lead to the formation of chloropicrin. The numerous potential precursors (of various reactivities) observed during this study, confirm this hypothesis. Combination of ozonation and chlorination can also lead to the formation of this compound, dangerous to health; however, the conditions of the formation and particularly the impact of a nitration reaction in the gas phase are still not clearly defined.
From a macroscopic point of view, corrosion of Zn alloy coated steel sheet occurs by the coating preceding corrosion mechanism; microscopically, however, the coated layer corrosion velocity in the tip of corrosion is different. In order to find the main factors of under-film corrosion of Zn and Zn-Fe alloy coatings in the salt water spray atmospheric exposure test, the correlation between point inflation-exfoliation width and chlorine penetration behavior, point adhesion, and the difference in chlorine penetration behavior due to alloy coating components were investigated. Consequently, the following results were obtained: 1. The better correlation was observed between chlorine penetration distance and point inflation-point exfoliation width. 2. The durability of coating against chlorine penetration improved by increase in point adhesion and Zn content in the coating layer. 3. Zn-Fe ...
The degradation of chlorinated solvents by reduction at the surface of zero-valent metals and bimetallic systems has emerged as an important approach to the in-situ remediation of ground water. Reduction by iron metal was studied in batch and column systems to develop a mechanistic understanding of the reaction chemistry and to determine the factors that affect dechlorination rate and long term performance in field applications.
Chemical oxidation is a treatment technology that uses powertul chemical oxidizers to destroy organic contaminants. Typical oxidizers used in chemical oxidation processes include ozone, hydrogen peroxide, chlorine, and potassium permanganate. The chemical reaction products are usually simple organic compounds, such as carboxylic acids, and/or inorganic compounds, such as carbon dioxide, water, and simple inorganic complexes (e.g., chloride salts, in the case of chemical oxidation treatment of chlorinated solvents).
In equipment industries, the equipments handling industrial water and pure water are numerous. In power generation including nuclear power generation, water serves as a working medium. Review is made on the experiences in the corrosion of iron and nickel base alloys in high temperature, high pressure water and the results of researches derived from them. Under high temperature and high pressure, carbon steel, low alloy steel, stainless steel and high nickel alloy cause corrosion even in pure water. But in the case of serious corrosion, chlorine, oxygen, alkali and others in water take part. The following matters are described: corrosion by steam; stress corrosion cracking in pure water; corrosion by impurities in high temperature, high pressure pure water, i.e. chlorine ions, ...
... detected (and reported) as a by-product of MRM screening (MS/MS) targeted by Law or Rule ... detected (and reported) as a by-product of MRM screening (MS/MS) targeted by Law or Rule ...
Computer programs have been developed to define the temperature increase which would be needed to bring deep-ocean water into density equilibrium with surface water for locations where data are available. A series of continuous-flow studies on phytoplankton blooms resulting from mixtures of 80 percent deep and 20 percent surface water in 2000-liter concrete culturing vessels (''reactors'') has been completed. A quantitative determination of nutrient utilization and flow through a combined primary and secondary trophic level system has been completed. This study utilized the clam Tapes semidecussata, fed from phytoplankton grown in 80 percent deep and 20 percent surface water. An analysis of the fate of the deep water discharged from a floating OTEC plant indicates that horizontal containment of the resulting deep water: ...
The catalytic oxygen transfer properties of vanadium containing zeolites and vanadium based sol-gel catalysts with hydrogen peroxides are well known. The severe problem of vanadium leaching caused by the presence of the by-productwater has been addressed. To avoid any interference with homogeneously catalyzed reactions, our study focusses on selective oxidations in a moisture-free medium with tert.-butylhydroperoxide. We have investigated the catalytic properties of amorphous microporous materials based on SiO{sub 2}, TiO{sub 2}, ZrO{sub 2} and Al{sub 2}O{sub 3} as matrix material and studied the effects of surface polarity on the oxidation of 1-octene and cyclohexane. (orig.)
Natural sunlight induces a genotoxic response in cultured CHO cells pre-treated with shale oil retort process water. Near ultraviolet light (NUV) component of the solar spectrum is the apparent radiation responsible for photoactivation. Cultured human skin fibroblasts are acutely sensitive to the genotoxic effects of photoactivated process water. The mutagenic potential of photoactivated process water in human cells is the same as that witnessed for an equivalent killing dose of the potent skin carcinogen FUV. DNA repair processes are involved in modulating genotoxic effects of this photo-induced process. The exact magnitude of the potential health-related and environmental risks resulting from photoactivation of retort process waters and other oil shale by-products is unassessed at this time. Our demonstration that a significant rate of mutation occurs in cultured human cells ...
After confirming that residual chlorine in tap water, which is regarded as one of the major cause of pitting corrosion, can be decomposed/removed by the irradiation of UV light, effect of dechlorinated water obtained based on this principle on the prevention of pitting corrosion, generation and growth, of the copper tubing was investigated by a corrosion test simulated the actual system in high buildings. (1) Low pressure type mercury lamp easily decompose/remove the residual chlorine. (2) If the dechlorinated water is supplied from the initial stage of copper tube usage, potential of the copper tube remains at the level of 100 mV/SCE and the generation of pitting corrosion is not observed. (3) Even when pitting corrosion is already found, switching to dechlorinated water in the midway reduces the potential of the copper tube down to 50 - 70 mV level, at the ...
The solvation properties of a chlorine ion in small water clusters are investigated using state-of-the-art statistical mechanics. The simulations employ the polarizable water model developed recently by Dang [J. Chem. Phys. [bold 97], 2659 (1992)]. The ion--water interaction potentials are defined such that the successive binding energies for the ionic clusters, and the solvation enthalpy, bulk vertical binding energy, and structural properties of the aqueous solution agree with the best available results obtained from experiments. Simulated vertical electron binding energies of the ionic clusters Cl[sup [minus
Concentrations of ammonia and the chlorine stabilizer, cyanuric acid, which could be expected in swimming pools decreased the rate of kill by chlorine of the potential pathogen, Pseudomonas...Full Text Available
In January 1994, a 6.7 magnitude earthquake in southern California ruptured a pipeline releasing approximately 4,200 barrels of blended San Joaquin Valley crude oil. A smaller volume entered the Santa Clara River and flowed 25 km downstream to an emergency containment dam. Ruptured water mains and chlorinated discharges from a damaged sewage treatment plant also affected water quality in the river. Quantitative injury assessment studies were initiated within days of the spill and included water/sediment chemistry, benthic macroinvertebrate community analyses and aquatic toxicity tests. Water quality values for TPH, BTEX, and chlorine ranged from nondetectable to 78 mg/l (TPH), nondetectable to 5.4 microg/l (total BTEX constituents) and nondetectable to 600 microg/l (residual chlorine) within 72 hours of the spill. Ammonia concentrations ...
This report describes the arrangement and features of the Ogishima thermal power plant facilities, as well as activities being performed there for operation control, regular inspection and improvement in reliability. The power plant uses about 48 percent of the by-product gas as its fuel to supply about 81 percent of the required power. Operation of the No. 1 unit started in 1976. Currently, the plant has three units, each with an output of 125MW. Each unit consists of a natural circulation boiler with a maximum evaporation capacity of 410 ton/hour and a reheat regenerative condensing turbine with a main vapor pressure of 127 kg/cm/sup 2/G. Techniques used for water properties control and combustion control are also described. In the plant, convetional time management integrity techniques are now being replaced by state management integrity techniques that determines the deterioration tendency in separate sections of the facilities which are ...
The coke plant at the Sparrows Point Plant consist of three coke oven batteries and two coal chemical plants. The by-product coke oven gas (COG) consists primarily of hydrogen, methane, carbon monoxide, nitrogen and contaminants consisting of tars, light oils (benzene, toluene, and xylene) hydrogen sulfide, ammonia, water vapor and other hydrocarbons. This raw coke oven gas needs to be cleaned of most of its contaminants before it can be used as a fuel at other operations at the Sparrows Point Plant. In response to environmental concerns, BSC decided to replace much of the existing coke oven gas treatment facilities in the two coal chemical Plants (A and B) with a group of technologies consisting of: Secondary Cooling of the Coke oven Gas; Hydrogen Sulfide Removal; Ammonia Removal; Deacification of Acid Gases Removed; Ammonia Distillation and Destruction; and, Sulfur Recovery. This combination of technologies will replace the existing ammonia ...
The coke plant at the Sparrows Point Plant consist of three coke oven batteries and two coal chemical plants. The by-product coke oven gas (COG) consists primarily of hydrogen, methane, carbon monoxide, nitrogen and contaminants consisting of tars, light oils (benzene, toluene, and xylene) hydrogen sulfide, ammonia, water vapor and other hydrocarbons. This raw coke oven gas needs to be cleaned of most of its contaminants before it can be used as a fuel at other operations at the Sparrows Point Plant. In response to environmental concerns, BSC decided to replace much of the existing coke oven gas treatment facilities in the two coal chemical Plants (A and B) with a group of technologies consisting of: Secondary Cooling of the Coke oven Gas; Hydrogen Sulfide Removal; Ammonia Removal; Deacification of Acid Gases Removed; Ammonia Distillation and Destruction; and, Sulfur Recovery. This combination of technologies will replace the existing ammonia ...
Atrazine (ATR) has been widely applied in the US and Mid Western states. Recently, public health and ecological concerns have been raised about contamination of surface and ground water by ATR and its chlorinated metabolites, due to their toxicity and potential carcinogenic or endocrinology effects....
This report documents the investigation regarding the failure of CPVC piping that was used to connect a solar hot water system to standard plumbing in a home. Details of the failure are described along with numerous pictures and diagrams. A potential failure mechanism is described and recommendations are outlined to prevent such a failure.
Apoptosis and Proliferation During DicWoroacetic Acid (DCA) Induced Hepatocellular Carcinogenesis in the F344 Male Rat Chlorine, introduced into public drinking \\\\'ater supplies for disinfection, can react with organic compounds in surface waters to form toxic by-prod...
The issues of the geothermal resource at Brady's Hot Springs are dealt with: the prospective supply of feedstocks to the ethanol plant, the markets for the spent grain by-products of the plant, the storage, handling and transshipment requirements for the feedstocks and by-products from a rail siding facility at Fernley, the probable market for fuel ethanol in the region, and an assessment of the economic viability of the entire undertaking.
One proposed solution to the problem of ballast-mediated aquatic invasions involves chemically treating ballast water to kill key target organisms. Here, we examine the efficacy of three commercially available ballast water biocides using vegetative microalgae, dinoflagellate resting cysts and bacteria as test organisms. Chemicals tested were the ballast water biocides SeaKleen and Peraclean Ocean, and the chlorine dioxide biocide Vibrex. Results demonstrate that the applicability of each of the three chemical biocides as a routine ballast water treatment is limited by factors such as cost, biological effectiveness and possible residual toxicity of the discharged ballast water (assessed on the basis of impact on motility of vegetative marine microalgae). Of the three biocides tested, Perac...
The Tennessee Valley Authority (TVA), the Electric Power Research Institute (EPRI), and the Department of Energy-National Energy Technologies Laboratory (DOE-NETL) are evaluating and demonstrating integration of terrestrial carbon sequestration techniques at a coal-fired electric power plant through the use of Flue Gas Desulfurization (FGD) system gypsum as a soil amendment and mulch, and coal fly ash pond process water for periodic irrigation. From January to March 2002, the Project Team initiated the construction of a 40 ha Carbon Capture and Water Emissions Treatment System (CCWESTRS) near TVA's Paradise Fossil Plant on marginally reclaimed surface coal mine lands in Kentucky. The CCWESTRS is growing commercial grade trees and cover crops and is expected to sequester 1.5-2.0 MT/ha carbon per year over a 20-year period. The concept could be used to meet a portion of the timber industry's needs while simultaneously ...
Oxyanions of uranium, selenium, chromium, arsenic, technetium, and chlorine (as perchlorate) are frequently found as contaminants on many DOE sites, and in other areas of the U.S.. A potential remediation method is to react the contaminated water with zero-valent iron (ZVI). We are performing fundamental investigations of the interactions of the relevant compounds with Fe filings and single- and poly-crystalline surfaces. The aim of this work is to develop the physical and chemical understanding that is necessary for the development of cleanup techniques and procedures.
Soils and groundwater beneath an abandoned Process sewer line in the A/M Area of the Savannah River Site (SRS) contain elevated levels of volatile organic compounds, specifically trichloroethylene (TCE) and tetrachloroethylene (PCE), two common chlorinated solvents. These compounds have low aqueous solubilities, thus when released to the subsurface in sufficient quantity, tend to exist as immiscible fluids or nonaqueous phase liquids (NAPLs). Because chlorinated solvents are also denser than water, they are referred to by the acronym DNAPLS, or dense non aqueous Phase liquids. Technologies targeted at the efficient characterization or removal of DNAPL are not currently proven. For example, most DNAPL studies rely on traditional soil and water sampling and the fortuitous observation of immiscible solvent. Once DNAPL is identified, soil excavation (which is only applicable to small contained spill sites) ...
Soils and groundwater beneath an abandoned process sewer line in the A/M Area of the Savannah River Site (SRS) contain elevated levels of volatile organic compounds, specifically trichloroethylene (TCE) and tetrachloroethylene (PCE), two common chlorinated solvents. These compounds have low aqueous solubilities, thus when released to the subsurface in sufficient quantity, tend to exist as immiscible fluids or nonaqueous phase liquids (NAPLs). Because chlorinated solvents are also denser than water, they are referred to by the acronym DNAPLs, or dense non-aqueous phase liquids. Technologies targeted at the efficient characterization or removal of DNAPL are not currently proven. For example, most DNAPL studies rely on traditional soil and water sampling and the fortuitous observation of immiscible solvent. Once DNAPL is identified, soil excavation (which is only applicable to small contained spill sites) ...
Gas-insulated systems employing SF/sub 6/ are utilized in a variety of applications in power delivery systems. Because electric arcs, sparks or corona can decompose SF/sub 6/ into by-products having chemical properties different from SF/sub 6/, environmental concerns arise regarding inadvertent human exposures to electrically-decomposed SF/sub 6/. Biological assays in our laboratory using mammalian cell culture systems have revealed that SF/sub 6/, spark-decomposed under specific experimental conditions, can produce cell death. Chemical analysis of spark-decomposed SF/sub 6/ has identified the major decomposition pathways and by-products. Biological testing of individual by-products or by-product mixtures has indicated that these major decomposition products may not account for the majority of the cell killing effects seen in our assays. Further experiments have suggested that S/sub 2/F/sub 10/ may be ...
The aim of this work was to study the recovery of proteolytic and collagenolytic activities from rayfish (Raja clavata) viscera wastes. Initially, different parts of the gastrointestinal...Full Text Available
The coking plant is described with some details of coal supplies and coke quality. Engineering improvements to the by-product system and coke oven machines, major repair of two batteries, installation of a PLC-based monitoring and control system, and training of personnel are dealt with at greater length.
A sensitive and rapid method to evaluate toxic and genotoxic properties of drinking water supplied from Lake Trasimeno (Umbria, Central Italy) was worked out analysing bile in Cyprinus carpio exposed for 20d to lake water treated with 3 different disinfectants, sodium hypochlorite (NaClO), chlorine dioxide (ClO2) and peracetic acid (PAA). Fish were sacrificed at 0, 10 and 20d in order to investigate the time course of these endpoints. An aliquot of bile samples was fractionated by adsorption on C18 silica cartridges and the genotoxic potential of whole bile and of bile fractions was evaluated by the single-cell microgel-electrophoresis (comet) assay on human colonic adenocarcinoma cells (Caco-2). Bile (both whole and fractionated) from specimens exposed to the three disinfectants always sh...
Plutonium and minor actinides produced as by-products of the UO_2 nuclear cycle could be considered as waste or energy source depending on the strategy selected in the nuclear energy programme. Considering Pu and Minor Actinides as a source, they can be burned in existing water reactor for diminishing the radiotoxicity of the spent fuel, it is necessary to use 'inactive' materials as matrix like ThO_2. ThO_2 matrix has demonstrated its Pu burning efficiency and higher corrosion resistance than UO_2. Uranium-plutonium mixed oxide (MOX) fuel efficiency is low because the presence of U in MOX results in the creation of some new Pu under irradiation. The dissolution behaviour of irradiated (Th,Pu)O_2 pellets with burn-up of 38.8 MWd/kg Th has been studied in carbonated (20 mM HCO_3"-), deionised and granite ground water solution in a hot cell. The dissolution behaviour of Th, Pu, U and Np was studied in order to find out ...
Alkaline promoted active carbon supported iron catalysts are very active in the oxidative dehydrogenation of ethylbenzene to styrene in the presence of carbon dioxide. The best results were obtained at 550 C for a Li-promoted catalyst with a conversion of ethylbenzene of 75% and a selectivity towards styrene of nearly 95%. These results are better than those obtained with industrial catalysts which perform the dehydrogenation process with an excess of water. The main product of the dehydrogenation reaction with CO{sub 2} was styrene, but the following by-products were detected - benzene and toluene. The selectivity towards toluene was always higher than towards benzene. We observed also the formation of carbon monoxide and water, which were produced with a constant molar ratio of about 0.8. The weight of the catalysts increased up to 20% during the reaction due to deposition of carbon. Using a too large excess of CO{sub 2} ...
This final report for the Swiss Federal Office of Energy looks at the possibilities for improved waste water utilization in the Lavey-les-Bains thermal spa, Switzerland. According to the regulations in force, the temperature of the waste water rejected into the Rhone river shall not exceed 30 {sup o}C, what is currently not the case. Also the operational cost shall be reduced and the waste water quality improved. The installations are presented. From the two geothermal wells, mineral water comes out at an average flow rate of 940 l/min and a temperature of 63 {sup o}C. Actual waste water data are reported. The measured thermal water consumption data, including seasonal variations, are analysed by computerized simulation and measures to reduce the consumed volume by the optimization of internal procedures are evaluated. Measures to reduce the quantity of the ...
This final report for the Swiss Federal Office of Energy looks at the possibilities for improved waste water utilization in the Lavey-les-Bains thermal spa, Switzerland. According to the regulations in force, the temperature of the waste water rejected into the Rhone river shall not exceed 30 "oC, what is currently not the case. Also the operational cost shall be reduced and the waste water quality improved. The installations are presented. From the two geothermal wells, mineral water comes out at an average flow rate of 940 l/min and a temperature of 63 "oC. Actual waste water data are reported. The measured thermal water consumption data, including seasonal variations, are analysed by computerized simulation and measures to reduce the consumed volume by the optimization of internal procedures are evaluated. Measures to reduce the quantity of the rejected free ...
Chlorine is not just one of many chemical feedstocks which is used in a few definitely harmful products like PVC or CFC but is irrelevant in all other respects. Just the opposite is true: There is hardly any product line of the chemical industry that can do without chlorine, from herbicides and pesticides to dyes, plastics, pharmaceuticals, photographic atricles, and cosmetics. Chlorine is not only a key element of chemical production but also an ubiquitous element of everyday life in civilisation. There are even many who would agree that the volume of chlorine production is an indicator of the competitive strength and national wealth of a modern society. By now, however, it has become evident that the unreflected use of chlorine is no longer ecologically acceptable. The consequences of a chlorine phase-out as compared to the continued ...
This paper summarizes substance flow analyses for four organic substances in the City of Stockholm, Sweden: diethylhexyl phthalate (DEHP), alkylphenolethoxylates (APEO), polybrominated diphenylethers (PBDE) and chlorinated paraffins (CP). The results indicate that the stocks of APEO, PBDE and CP all are approximately 200-250 tonnes, whereas the DEHP stock is two orders of magnitude larger. Emissions can be linked to imported consumer goods such as electronics (PBDE) and textiles (APEO), and to construction materials (DEHP, CP). For several of the substances considerable amounts remain in the technosphere for a long time, even after use of the substance in new products has been eliminated. For example, the use of DEHP as plasticizer for PVC plastics in cables and floorings has more or less been phased-out, but still these applications make up a stock of some 20,000 tonnes (85% of the total DEHP stock in Stockholm) and emit 28 tonnes of DEHP annually (93% of overall ...
The activated charcoal treatment in the field of the water treatment is applied to water supply, sewage, industrial water supply and industrial sewage, etc.. Its main treatment effects are (1) decolorization, (2) removal of odorous substance, (3) removal of organic material which is detected as COD or BOD, (4) removal of harmful substance, (5) removal of substance which could generate muddness and tarnish and (6) removal of organic material which affects the succeeding high degree treatment badly, etc.. Many actual application examples in the above fields have been reported. As the most recent topic, a big amount of the demand of activated charcoal is expected in the treatment of water supply. Chlorine which is used as disinfectant during the water purification process generates organic halogen compounds such as trihalomethane through the reaction with precursor ...
Humic acids are considered problematically in drinking water because it can react readily with chlorine to form carcinogen compounds and its biological removal is much recommended. The scanning electron microscopy morphologies and optical parameters observed for natural humic acids (NHAs) extracted from different soils at Mitidja plain (Algeria) made them different from the commercial ones. Three of the most active strains of 19 actinomycetes were isolated and selected from surface soils at this plain. These strains were identified based on cultural characteristics and chemotaxonomic analysis and classified in the genus Streptomyces. Growth of these strains was assured on a poor liquid medium containing NHAs as carbon and nitrogen sources and degradation occur only in the presence of gluco...
In front of the risks linked with the increase of the greenhouse gas emissions in the atmosphere, the decision makers must take into consideration first, the scientific advice of climatic change experts, and second, the considerable inertia of the climatic system. Thus, any action implemented so far will have an impact all along the 21. century and later whatever the future human activities. The aim of this memento is to sensibilize the decision makers about the possible consequences of their choice in terms of volume of greenhouse gases and of medium- and long-term evolution: 1 - stakes, role of local decision-makers (greenhouse effect and climatic change, France's international commitment, stakes, liabilities of local decision makers, decentralization laws, local plans of fight against greenhouse effect, public information and dialogue); 2 - urbanism and transports (urban displacements, alternatives to individual cars, collective transportation systems, parking, inter-region ...
This paper investigates various usages of natural gas (NG) as an energy source for different hydrogen production technologies. A comparison is made between the different methods of hydrogen production, based on the total amount of natural gas needed to produce a specific quantity of hydrogen, carbon dioxide emissions per mole of hydrogen produced, water requirements per mole of hydrogen produced, and a cost sensitivity analysis that takes into account the fuel cost, carbon dioxide capture cost and a carbon tax. The methods examined are the copper-chlorine (Cu-Cl) thermochemical cycle, steam methane reforming (SMR) and a modified sulfur-iodine (S-I) thermochemical cycle. Also, an integrated Cu-Cl/SMR plant is examined to show the unique advantages of modifying existing SMR plants with new h...
In this work, long-term operation of a pilot scale mixed anaerobic reactor processing crude glycerol and rapeseed meal is discussed. These materials are generated as by-products of biodiesel production. Mixed reactor was operated under mesophilic conditions for the period of 654 days. Total cumulative production of biogas reached 379 m3 (at atmospheric pressure and ambient temperature). Maximum volumetric loading achieved during the operation was 2.17 kg m?3 d?1 for the crude glycerol dose of 2 L. When dosing crude glycerol as a single substrate, average specific production of biogas of 0.76 m3 per L of the g-phase was achieved. The lack of nutrients in the g-phase had to be compensated by an addition of ammonium nitrogen in the form of urea into the reactor. Long term processing of crude ...
The influence of sediment dwelling macroinvertebrates on fate and bioavailability of contaminants in freshwater systems was determined using the burrowing mayfly, Hexagenia limbata, as a representative benthic organism. Two series of experiments were conducted: the first to determine the effect of mayflies on movement of contaminants into sediment and organisms, and the second to examine the effect of mayflies on release of contaminants from sediments to the water column and their subsequent accumulation in fish. Concentrations of "1"4C labelled DDT, hexachlorobenzene (HCB), and dihexylphthalate (DHP) in water were 0.11 +/- 0.01, 0.062 +/- 0.005 and 0.006 +/- 0.007 ppb, respectively. Total mass of DHP in the burrow wall was about equal to mass on the surface, indicating that mayflies were capable of doubling the amount of DHP sorbed per unit surface area of sediment. Adsorption of contaminants from water pumped through ...
Polychlorinated n-alkanes (PCAs) are group of chemicals manufactured by chlorination of liquid n-paraffin or paraffin wax that contain 30 to 70% chlorine by weight. Large amounts of PCAs are widely used as plasticizers for vinyl chloride, lubricants, paints, and flame retardants and number of other industrial applications. Annual global production of PCAs is approximately 300 kilo tones, with a majority having medium-carbon-chain (C14-C19) length. According to the investigation made by Kagaku Kogyo Nippon-Sha, the annual consumption of PCAs in Japan was about 83,000 tons in between 1986-2001. Short-carbon-chain (C10-C13) has been placed on the Priority Substance List under Canadian Environmental Protection Act and on the Environmental Protection Agency Toxic Release Inventory in the USA due to its potential to act as tumor promoters in mammals. Data on environment levels of PCAs is meager, nevertheless, PCAs have been measured at relatively ...
Because of the environmental hazard of organic solvents such as chlorinated or aromatic hydrocarbons, water soluble and biodegradable substitutes have come into use. It should be assessed how they affect soil and aquifer when spilled in leaks or accidents. This was simulated in a model system using methanol and percolation columns, one filled with material from the unsaturated subsurface and two with different materials from aquifers. The results reveal that a spill of the substitutes can also cause problems. In homogeneous soils and at long retention times until the substance reaches the aquifer, sorption and biological degradation are most likely to prevent contamination of the groundwater. When oxygen supply in the subsurface is insufficient, reducing conditions occur and sulphide is formed. The data show that much more methanol was eliminated than reflected by the consumption of electron acceptors. This indicates that sorption and anabolic ...
A $200 million paper mill being built in Hagerstown, Md., is expected to produce 150,000 bone-dry short tons per year of de-inked, market-grade pulp for writing and printing paper. The 1st Urban Fibers facility, the largest capital project in Hagerstown's history, is slated for completion in the spring. Landegger Recycled Fiber Corp. will operate and maintain the 200,000-square-foot recycling mill and 60,000-square-foot water reclamation plant. The wastepaper recycling mill plans to minimize waste and pollution by: reclaiming 635 tons per day of 100 percent post-consumer mixed office waste from the solid waste stream; saving more than 16 million cubic feet of landfill area per year; conserving the fiber equivalent of 6,700 trees per day; using no chlorine; saving about 2,000 gallons of water and 4,000 kilowatt hours of electricity per ton of throughput, compared to virgin fiber mills; reusing treated wastewater, ...
This article includes a section on the coke and by-products plant. A 60-oven battery of 6-metre Kaiser-Dialer ovens produces 1800 tons of blast furnace coke a day. A coal blend mixture of 88% high volatile and 12% low volatile is used.
Molybdenum is separated from molybdenum-containing activated charcoal or char also containing small amounts of uranium obtained as a by-product in uranium leaching processes by stripping with an alkaline solution to provide a molybdenum containing solution containing substantially less than 500 ppm u/sup 3/o/sup 8/.
...and supply ensuring better food quality for the consumer developing safer and more flexible food production processes and technologies raw materials for food production; production and processing systems; by-products and wastes from fisheries and agro-industry; new food sources; packaging systems; quality monitoring; traceability Food contamination detecting and eliminating infectious and toxic agents throughout the food chain establishing the hazards and origins of food contaminants producing food more safely rapid ...
This paper shows the characteristics of the fertilizer production park of the State of Minas Gerais, Brazil, mainly in the aspects of energy consumption and energy sources used in the production process of the various kinds of fertilizers and by-products. A scenario including the fertilizer production evolution was made, relating this future production with the future energy consumption of this sector. 7 figs., 2 tabs.
The report gives results of the first 3 years of study to determine environmentally sound methods for disposing of wastes from nonregenerable flue gas desulfurization systems. Untreated and treated wastes from seven different scrubbers at eastern and western plants, using lime, l...
The report gives results of a 4-year study to determine environmentally sound methods for disposing of wastes from nonregenerable flue gas desulfurization (FGD) systems. Data presented incorporates results obtained during the fourth year with material from report EPA-600/7-77-052...
The synthesis and degradation of anthropogenic and natural organohalides are the basis of a global halogen cycle. Chlorinated hydroquinone metabolites (CHMs) synthesized by basidiomycete fungi and present...Full Text Available
The kinetics of the degradation of trichloroethylene (TCE) and seven other chlorinated aliphatic hydrocarbons by Methylosinus trichosporium OB3b were studied. All experiments were performed with cells...Full Text Available
An assessment has been made of biochemical alterations in renal and hepatic functions of 73 male operators employed for an average of 8.2 years (range 0.5-23 years) in a chemical plant producing chlorinated...Full Text Available
The paper gives results of a study to identify active sites and surface functional groups that may contribute to the absorption of elemental mercury (Hg) by relatively inexpensive calcium (Ca)-based sorbents. The study investigated the formation of chlorine (Cl) sites in CA-based sorbents as well as their role and reactivity in the absorption of Hg. HCl-exposed calcium sulfate dihydrate (gypsum) exhibited a superior Hg sorption capability. Crystalline water molecules on the surface of the gypsum were confirmed to contribute indirectly to Hg uptake. These surface molecules may have absorbed HC1 through hydrogen bond formation between an oxygen atom of a crystalline water molecule and a hydrogen atom of an HCl molecule. Two adjacent, physically absorbed HCl molecules could then trap an Hg molecule through formation of a mercuric-chloride-like molecule. Significant correlations between Cl and Hg uptake by gypsum were noted.
The paper gives results of a study to identify active sites and surface functional groups that may contribute to the absorption of elemental mercury (Hg) by relatively inexpensive calcium (Ca)-based sorbents. The study investigated the formation of chlorine (Cl) sites in CA-based sorbents as well as their role and reactivity in the absorption of Hg. HCl-exposed calcium sulfate dihydrate (gypsum) exhibited a superior Hg sorption capability. Crystalline water molecules on the surface of the gypsum were confirmed to contribute indirectly to Hg uptake. These surface molecules may have absorbed HC1 through hydrogen bond formation between an oxygen atom of a crystalline water molecule and a hydrogen atom of an HCl molecule. Two adjacent, physically absorbed HCl molecules could then trap an Hg molecule through formation of a mercuric-chloride-like molecule. Significant correlations between Cl and Hg uptake by gypsum were noted.
A laboratory-scale multi-layer system was developed for the adsorption of PCDD/Fs from gas streams at various operating conditions, including gas flow rate, operating temperature and water vapor content. Excellent PCDD/F removal efficiency (>99.99%) was achieved with the multi-layer design with bead-shaped activated carbons (BACs). The PCDD/F removal efficiency achieved with the first layer adsorption bed decreased as the gas flow rate was increased due to the decrease of the gas retention time. The PCDD/F concentrations measured at the outlet of the third layer adsorption bed were all lower than 0.1ng I-TEQNm-3. The PCDD/Fs desorbed from BAC were mainly lowly chlorinated congeners and the PCDD/F outlet concentrations increased as the operating temperature was increased. In addition, the r...
The Raywell Process Plants unit, which reclaims a wide range of organic solvents, including chlorinated hydrocarbons, is based on thin film evaporation and distillation rather than steam distillation, thus reducing the risk of contamination by water. Henry Balfour and Co.'s Pfaudler Solvent Recovery System gives 96% or better solvent recovery and produces a near-solid waste suitable for landfill disposal; like the Raywell system, it uses a mechanically wiped thin-film evaporator. Midland Oil Refineries uses sa Raywell thin-film evaporator for recovery of waste lubricating oils rather than the conventional sulfuric acid/clay treatment, thus avoiding formation of sulfuric acid sludge waste. The Henry Balfour Bioenergy anaerobic digestion system gives yields of fuel gas with 65-75% methane as high as 0.8 cu m/kg BOD; it achieves 95-98% BOD removal with no pH control or nutrient addition because it separates solids from liquid effluent and ...
This paper investigates various usages of natural gas (NG) as an energy source for different hydrogen production technologies. A comparison is made between the different methods of hydrogen production, based on the total amount of natural gas needed to produce a specific quantity of hydrogen, carbon dioxide emissions per mole of hydrogen produced, water requirements per mole of hydrogen produced, and a cost sensitivity analysis that takes into account the fuel cost, carbon dioxide capture cost and a carbon tax. The methods examined are the copper-chlorine (Cu-Cl) thermochemical cycle, steam methane reforming (SMR) and a modified sulfur-iodine (S-I) thermochemical cycle. Also, an integrated Cu-Cl/SMR plant is examined to show the unique advantages of modifying existing SMR plants with new hydrogen production technology. The analysis shows that the thermochemical Cu-Cl cycle out-performs the other conventional methods with respect to fuel ...
This paper investigates various usages of natural gas (NG) as an energy source for different hydrogen production technologies. A comparison is made between the different methods of hydrogen production, based on the total amount of natural gas needed to produce a specific quantity of hydrogen, carbon dioxide emissions per mole of hydrogen produced, water requirements per mole of hydrogen produced, and a cost sensitivity analysis that takes into account the fuel cost, carbon dioxide capture cost and a carbon tax. The methods examined are the copper-chlorine (Cu-Cl) thermochemical cycle, steam methane reforming (SMR) and a modified sulfur-iodine (S-I) thermochemical cycle. Also, an integrated Cu-Cl/SMR plant is examined to show the unique advantages of modifying existing SMR plants with new hydrogen production technology. The analysis shows that the thermochemical Cu-Cl cycle out-performs the other conventional methods with respect to fuel ...
Ammonia borane (AB) and sodium borohydride (SBH) are candidate materials for on-board hydrogen storage that can be dehydrogenated upon demand. The rheological properties of the dehydrogenated by-products are important to quantify their removal and transportability from the hydrogen storage system. This paper presents visco-elastic property (elastic stiffness and viscous damping) measurements of the spent fuels obtained from AB hydrolysis, hydrothermolysis and thermolysis; and SBH hydrolysis. Smaller stiffness and larger mobility (or smaller viscous damping) indicate better transportability of the spent fuel. In addition, flow property (dynamic angle of repose and avalanching time) measurements for the hydrolysis spent fuels of AB and SBH are also presented. Comparing with the SBH hydrolysis spent fuel, the AB hydrolysis spent fuel had a lower stiffness and larger mobility, as well as lower angles of dynamic repose and avalanche power peaks, indicating that it is ...
Upgrading of oil palm empty fruit bunch (EFB), which is a main by-product of palm oil industry, to animal feeds by radiation pasteurization and fermentation was investigated for recycling the agro-resources and reducing the environmental pollution. The following results were obtained: 1) The necessary dose for pasteurization of EFB contaminated by various microorganisms including aflatoxin producing fungi was determined as 10 kGy. The chemical and biological properties of EFB were changed little by irradiation up to 50 kGy. 2) In the fermentation process, Pleurotus sajor-caju was selected as the most effective fungi and the optimum condition for fermentation was clarified. The process of fermentation in suspension was also established for the liquid seed preparation. 3) The digestibility and nutritional value of fermented products were evaluated as ruminant animal feeds and the mushroom can be produced as by-product. 4) The pilot plant named ...
An 8-week feeding trial was conducted to evaluate the use of local poultry by-product meal (PBM) in replacement of imported fishmeal in the diets of cobia, Rachycentron canadum. Six isolipidic (12%) and isoproteic (45%) experimental diets were formulated using PBM to replace fishmeal at 20, 40, 60, 80 and 100% dietary protein. Eleven juvenile cobia (initial mean weight of 30.7???0.78?g) were randomly stocked in 300-L circular fibreglass tanks and hand-fed based on the total biomass of each tank, twice a day at 0900?h and 1500?h. The fish were group weighed at 2-week intervals to monitor their growth performance in order to adjust the feeding ratio. At the end of the feeding trial, weight gains (WGs) ranging from 221 to 322% were obtained. The specific growth rate (SGR), WG and protein effi...
Because hydrogenation of coal to liquid products (oils) is accompanied by distributions of complex by-product mixtures (IOM, preasphaltenes, asphaltenes and gases) which change as a function of reaction variables (time, temperature and pressure) and reactor configuration, the determination of selectivity relationships for coal liquefaction catalysts has been a difficult and time-consuming task involving numerous experiments to adequately describe catalyst performance over a range of conditions. This paper describes a method for analyzing the experimental results of coal liquefaction reactions which may be applied to a number of aspects of coal liquefaction research and process control, including: rapid selectivity and performance screening for catalysts; correlation of laboratory results with process parameters; and optimization of product yield for plant process conditions. Catalyst selectivity and performance screening will be emphasized here. The approach to ...
The findings of a 9-month study of the feasibility of constructing and operating a 35 million gallon per year fermentation ethanol plant in the New Orleans area are presented. The unique features studied are the use of corn screenings, elevator by-products, and damaged grains as feedstock, and the use of municipal solid waste (MSW) as the process fuel. The plant will require investment outlays of $146 million, and the unit production cost for ethanol will be about $1.43 per gallon. The ethanol will be sold in the Louisiana and Texas markets. In Louisiana, gasohol benefits from an 8 cent per gallon state excise tax exemption as well as from the 4 cent per gallon federal excise tax exemption. The by-product, DDGS, will be sold to the overseas market. A large quantity of feedgrains and feedstuffs are exported from the port of New Orleans, and the plant's DDGS will have a price advantage over export feedgrains shipped from further inland.
The objectives of this project were to develop technologies to manufacture self-reducing briquettes out of waste iron oxides and to recycle them in an electric arc furnace or a cupola furnace. CRM has investigated and determined the optimal characteristics (binder, size, grain size, compositions and activator for the reduction reaction) for briquettes containing mixtures of mill scales, mill sludges, electric arc furnace (EAF) dust and coal as reduction agent. The goal of obtaining briquettes, in which iron oxides are totally reduced when these briquettes are loaded with the scrap into an electric arc furnace, was achieved. Trials at ProfilARBED have shown that it is possible to recycle mill and EAF by-products conditioned in self-reducing briquettes in an electric arc furnace without influence on the performance and on the environment. The iron content of the slag does not increase as the iron of the by-product is almost completely reduced. ...
Red mud, the by-product of alumina fabricating industry by the Bayer process, was investigated to produce light-weight aggregates for structural concrete. Owing to very high concentration of Fe{sub 2}O{sub 3} in the red mud, no light-weight aggregates could be sintered from the red mud alone. Thus, red mud being mixed with sewage sludge that is in its chemical composition very similar to the clay mineral, very light-weight aggregates with the apparent density smaller than 1.0 g/cm{sup 3} was able to be fired at 1,200 deg. C, by the bloating effect. For this purpose, the mixing ratio of red mud to sewage sludge must be held less than a unity. On the other hand, a mixture containing more red mud than sewage sludge required the addition of, for instance, limestone in 20-30 percent, so that medium-light weight aggregates of the apparent density ranging from 1.4 to 1.9 g/cm{sup 3} were prepared. The suitable sintering temperature was, in this case, 1,150 deg. C rather ...
A construction of a W_3-algebra for the SU(3) parafermion is proposed. The details of the calculation are given, in which the Z-algebra technique is used instead of the popular free field realization. We find that the W_3-algebra is closed at level k=3, and the central charge of the underlying algebra is different from known series of Fateev-Lykyanov W-algebras; as a by-product we get a field T"("4")(z), whose conformal dimension is 4, and is null at k=3. ((orig.)).
A previous paper introduced the use of wave digital filters as a basic building block for power system simulation, particularly suitable for real-time applications. This paper stresses the simulation of non-linear and switching elements, emphasizing the advantages of the wave filters implementation. The digital structure is maintained even when non-linear components change their characteristics or power electronic devices switch their states. As a very important by-product, the suppression of numerical oscillations related to the trapezoidal rule is achieved in a rather simple way, with no effects on simulation results.
A method for analyzing the experimental results of coal liquefaction reactions which is applicable to a number of aspects of coal liquefaction research and process control, including rapid selectivity and performance screening for catalysts; correlation of laboratory results with process parameters; and optimization of product yield with plant process conditions is described here. Ternary diagrams of product/by-product distributions for the coal liquefaction using Co/Mo catalysts combined with a hyperbolic relationship for the conversion of various hydrocarbon fractions can be used for catalyst screening. A hydrogen consumption diagram used to provide a more significant selectivity test than the hyperbolic correlation is also included. (BLM)
The proceedings document the presentations made during the symposium, which dealt with the status of flue gas desulfurization technology in the United States and abroad. Subjects considered included: regenerable, non-regenerable, and advanced processes; process costs; and by-product disposal, utilization, and marketing. The purpose of the symposium was to provide developers, vendors, users and those concerned with regulatory guidelines with a current review of progress made in applying processes for the reduction of sulfur dioxide emissions at the full- and semi-commercial scale. The 20 papers were abstracted and indexed separately.
This paper describes examples of the damage resulting from the impact of a whipping pipe on a nearby pressurised pipe. The work is a by-product of a study of the motion of a whipping pipe. The tests were conducted with small-diameter pipes mounted in rigid supports and hence the results are not directly applicable to large-scale plant applications where flexible support mountings are employed. The results illustrate the influence of whipping pipe energy, impact position and support type on the damage sustained by the target pipe.
This paper describes examples of the damage resulting from the impact of a whipping pipe on a nearby pressurised pipe. The work is a by-product of a study of the motion of a whipping pipe. The tests were conducted with small-diameter pipes mounted in rigid supports and hence the results are not directly applicable to large-scale plant applications where flexible support mountings are employed. The results illustrate the influence of whipping pipe energy, impact position and support type on the damage sustained by the target pipe. (author).
Air pollution constraints continue to intensify, resulting in solid waste volume increases. An example of this is coal burning power plant flue gas desulfurization by scrubbing. The aqueous suspensions of calcium sulfate hemihydrate or calcium sulfate dihydrate will exceed 200 million tons annually by the year 2000. Disposal of these wastes can have massive environmental effects, due to physical instability and leaching to groundwater. One alternate disposal technique is sulfopozzolanic fixation, converting the FGD waste by addition of fine coal ash and an alkaline earth additive, into a monolithic mass. 6 refs., 17 figs., 3 tabs.
This plan outlines the procedures and operations used at LLNL's Site 300 for the management of the hazardous waste generated. This waste consists primarily of depleted uranium (a by-product of U-235 enrichment), beryllium, small quantities of analytical chemicals, industrial type waste such as solvents, cleaning acids, photographic chemicals, etc., and explosives. This plan details the operations generating this waste, the proper handling of this material and the procedures used to treat or dispose of the hazardous waste. A considerable amount of information found in this plan was extracted from the Site 300 Safety and Operational Manual written by Site 300 Facility personnel and the Hazards Control Department.
As part of our effort to develop a semicontinuous PuO/sub 2/ reduction process, we are investigating promising materials for containing a 900/sup 0/C molten CaCl/sub 2/ . CaO chlorination reaction. We want the material to contain this reaction and to be reusable. We tested candidate materials in a simulated salt (no plutonium) using anhydrous HCl as the chlorinating agent. Data are presented on the performance of 36 metals and alloys, 9 ceramics, and 3 coatings.
Chlorine clearly inhibits the CO{sub 2}-gasification reaction of charcoal at 800{sup o}C. From this and other observations the picture emerges that the reduction in the gasification reactivity of the charcoal is intimately related to the deactivation of the catalytically active alkali metals residing in the wood due to the formation of the chloride salt. It is argued that the heavy metal chlorides will likely transfer the chlorine to the indigenous alkali metals during the pyrolysis stage of the wood. The fate of the thus formed alkali metal chlorides can then be either their removal from the sample (evaporation), or, when present at the gasification stage, re-activation (i.e., de-chlorination) under our gasification conditions. (author) 3 figs., 4 refs.
Ozone plays a critical role in both the chemistry and radiation balance of the troposphere. Understanding the factors controlling tropospheric ozone levels is critical to our understanding of a variety of issues in global chemistry and climate change. Chlorine atoms have the potential to contribute significantly to the ozone balance in the free troposphere. They can react directly with ozone or alternately, with organics and may actually lead to the formation of ozone in the presence of sufficient NO. Reactions of alkali halides in sea salt particles are a potential source of atomic chlorine, hence reactions of these alkali halides, especially those producing precursors to atomic chlorine, are of great interest. Finally, the mechanisms, intermediates and products of the Cl-biogenic reactions are unknown; these could serve as unique markers of chlorine atom chemistry in the troposphere, and hence are ...
aluminum electrolytic capacitors with Freon, trichloroethylene, carbon tetrachloride, or other chlorine or fluorine solvents. Aluminum electrolytic ...
Techniques for culturing, harvesting, and testing bacteria to evaluate bactericidal chemicals for swimming pools are described. Concentrations of 25, 50, and 100 mg of the chlorine stabilizer cyanuric...Full Text Available
Polychlorinated dibenzo-p-dioxins and dibenzo-furans form a family of more than 200 compounds which are relatively stable in the biosphere and tend to accumulate in the human body. The tetra- to hexa-chlorinated dioxins and furans are considered highly toxic. To facilitate the assessment of the total toxicity of dioxin and furan mixtures, the estimated toxic effects of the individual compounds relative to the 2,3,7,8-tetrachloro-dibenzo-p-dioxin (TCDD) were introduced as Toxic Equivalent Factors which yield, when multiplied with the respective concentrations, the Toxic Equivalent (TE) of the mixture. Toxic dioxins and furans are unintentionally formed in a number of industrial combustion processes such as waste incineration and iron ore sintering, in the chemical industry and in household heating. To keep the emissions as low as possible, off-gas clearing systems for the collection of dioxins and furans are increasingly prescribed by the authorities. In addition, ...
The Rio Grande alluvial floodplain aquifer between El Paso/Juarez and Fort Quitman, Texas has been intensively tilled and irrigated since 1910. Almost since that time, the Rio Grande and its interconnected alluvial aquifer in this stream reach have been affected by excessive salinity problems. Presently, salinity of surface water and groundwater increases from 800 to 2000 mg/L total dissolved solids (TDS) near El Paso, Texas to 2500 to 5500 mg/L TDS near Fort Quitman, Texas, approximately 115 km downstream. Chloride (Cl) and Chloride/Bromide (Cl/Br) ratios increase downstream, with a marked increase in salinity beginning about 45 km below El Paso. Groundwater sampling in an intensively investigated reach of the floodplain aquifer, extending from 35 to 60 km below El Paso identified two distinct water types. The first water type (17 samples) is a relatively dilute groundwater containing 1000 to 2000 mg/L TDS, 250 to 600 ...
Laser direct-write etching of the refractory metals Mo and W was developed using reactions in chlorine and nitrogen trifluoride vapors. Rate and high spatial resolution are simultaneously optimized using a two-vapor halogenation/development sequence, based on surface modification. Local-area laser chlorination of the metal surface is used to predispose areas to subsequent bulk etching.
The kinetics of the reaction of zirconium phosphates with carbon tetrachloride in sodium and potassium chloride melt as well as the effect of temperature, gas flow, solubility and weight of the solid phase of the phosphate, and stirring of the melt on the chlorination rate has been studied. The kinetic parameters of the reaction (rate constants, activation energy, etc.) have been calculated.
...contributions from the following fields: Catalytic elimination of environmental pollutants, such as nitrogen oxides, carbon monoxide, sulfur compounds, chlorinated and other organic compounds, ...contributions from the following fields: Catalytic elimination of environmental pollutants, such as nitrogen oxides, carbon monoxide, sulfur compounds, chlorinated and other organic compounds, ...
We study some aspects of the experimental behaviour of tachyons, in particular by finding out their <> shape. A Superluminal particle, which in its own rest frame is spherical or ellipsoidal (and with an infinite lifetime), would <> to a laboratory frame as occupying the whole region of space bound by a double cone and a two sheeted hyperboloid. Such a structure (the tachyon <>) rigidly travels with the speed of the tachyon. However, if the Superluminal particle has a finite lifetime in its rest frame, then in the laboratory frame it gets a finite space extension. As a by-product, we are able to interpret physically the imaginary units entering - as is well known - the transverse co-ordinates in the Superluminal Lorentz transformations. The various particular or limiting cases of the tachyon shape are thoroughly considered. Finally, some brief considerations concerning possible experiments to look for ...
The lignin, one of the main by-products of the pulp industry, can be used to remove dyes from textile wastewaters. The potential of the lignin for Brilliant Red HE-3B reactive dye removal from aqueous solutions at pH=1.5 was examined by the batch technique as a function of dye concentration, solution temperature and contact time. The Freundlich, Langmuir, Dubinin-Radushkevich and Tempkin adsorption isotherms were used to describe the data of sorption equilibrium and to determine its corresponding isotherm constants. The thermodynamic parameters DG, DH and DS were also determined; the obtained values show that the sorption of reactive dye on lignin is a spontaneous, endothermic and entropy-driven process. The kinetic of reactive dye sorption was analyzed using the pseudo-first order and pse...
Physical processes in the region of laser conversion for the next Linear Colliders (NLC) are discussed. The main goal of this conversion is to obtain high-energy intense #gamma# beams for #gamma#e and #gamma##gamma# colliders. This conversion has important by-products: (i) one can observe here effect of nonlinear QED (in a strong external field)-production of e"+e"- pairs by a high-energy photon and emission of very high-energy photons by an electron; (ii) one can produce and observe here the invisible axion in colliding #gamma#_0e beams. The NQED effects also result in variation of the spectra of high-energy photons and an additional background. 12 refs., 12 figs., 1 tab.
Oil and gas production and processing operations sometimes cause naturally occurring radioactive materials (NORM) to accumulate at elevated concentrations in by-product waste streams. The sources of most of the radioactivity are isotopes of "2"3"8U and "2"3"2Th series, which are naturally present in the subsurface formations from which oil and gas are produced. NORM waste may cause problems in the operations of installations by plugging perforations, clogging tubular and valves then restricting flow. Therefore, plants or equipment have to be refurbished and decontaminated before reuse to avoid radioactive waste or surface contaminated object. There are two options for safe disposal of scale and sludge produced from NORM Descaling Facility : 1- Injection into an abandoned production well. 2- The construction of a near surface depository. These options are assumed to be environmental friendly disposal options. (author)
A computer modelling has been developed for the calculation of mass balance of monazite ore break-down by alkali process at Rare Earth Research and Development Center. The process includes the following units : ore digestion by concentrate NaOH, dissolution of digested ore by HCl, uranium and thorium precipitation and crystallization of Na3PO4 which is by-product from this process. The model named RRDCMBP was prepared in Visual Basic language. The modelling program can be run on personal computer and it is interactive and easy to use. User is able to choose any equipment in each unit process and input data to get output of mass balance results. The model could be helpful in the process analysis for the further process adjustment and development.
Jatropha is a nonedible oil seed plant belonging to Euphorbiaceae family. Global awareness of sustainable and alternative energy resources has propelled research on Jatropha oil as a feedstock for biodiesel production. During the past two decades, several cultivation projects were undertaken to produce Jatropha oil. In future, the increased cultivation of toxic Jatropha plants and utilization of its agro-industrial by-products may raise the frequency of contact with humans, animals, and other organisms. An attempt was thus made to present known information on toxicity of Jatropha plants. The toxicity of Jatropha plant extracts from fruit, seed, oil, roots, latex, bark, and leaf to a number of species, from microorganisms to higher animals, is well established. Broadly, these extracts posse...
This study addresses the solar thermal decomposition of natural gas for the co-production of hydrogen, as well as Carbon Black as a high-value nano-material, with the bonus of zero CO2 emissions. The work focused on the development of a medium-scale solar reactor (10kW) based on the concept of indirect heating. The solar reactor is composed of a cubic cavity receiver (20cm side), which absorbs concentrated solar irradiation through a quartz window via a 9cm-diameter aperture. The reacting gas flows inside four graphite tubular reaction zones that are settled vertically inside the cavity. Experimental results were as follows: methane conversion and hydrogen yield of up to 98% and 90%, respectively, were achieved at 1770K, and acetylene was the most important by-product, with a mole fraction...
Rice husk generated as a by-product of rice processing is an important energy resource. The availability of this resource in India has been assessed and the technologies for exploitation of its energy potential in rice processing industry discussed. Nomographs have been developed for estimation of the husk required to meet the energy demand of parboiling, drying and milling operations. The unit cost of electricity using rice husk gasifier-based power generation systems has been calculated and its financial feasibility assessed in comparison with utility-supplied and diesel-generated electricity. With the cost and efficiency data assumed here, the unit cost of electricity produced by rice husk gasifier-dual fuel engine-generator system varies between Rs 2/kWh and Rs 7/kWh. (author)
Rice husk generated as a by-product of rice processing is an important energy resource. The availability of this resource in India has been assessed and the technologies for exploitation of its energy potential in the rice processing industry discussed. Nomographs have been developed for estimation of the husk required to meet the energy of parboiling, drying and milling operations. The unit cost of electricity using rice husk gasifier-based power generation systems has been calculated and its financial feasibility assessed in comparison with utility-supplied and diesel-generated electricity. With the cost and efficiency data assumed here, the unit cost of electricity produced by rice husk gasifier-dual fuel engine-generator system varies between Rs 2/kWh and Rs 7/kWh. (35 Rs approximates to SUS 1.). (author)
Discusses results of investigations into catalytic properties of various minerals during hydrogenation of Kansk-Achinsk brown coal with a view to replacing synthetic compositions based on molybdenum. Describes tests and equipment used in hydrogenation of grade B-2 Borodinsk deposit coal in tetralin (hydrogen donor). Various by-products of metallurgical processes and compounds separated from tailings containing mainly iron and sulfur and other metals were used as catalysts. States that: minerals containing iron compounds in the form of pyrites, hematites and magnetites exhibit catalytic properties when used in the hydrogenation of brown coal; pyritic catalysts enrich liquid products with hydrogen while sulfur and nitrogen content remains the same; the yield of malthenes with pyritic catalysts is no lower than with alumocobaltmolybdenum catalysts. 18 refs.
Red mud is a by-product of bauxite processing through Bayer process. The amount of red mud generated depends largely on the type of ore used and the processing. Use of red mud as a catalyst can be a good alternative to the existing commercial catalysts. Its properties such as iron content in form of ferric oxide (Fe{sub 2}O{sub 3}), high surface area, sintering resistance, resistance to poisoning and low cost make it an attractive potential catalyst for many reactions. Besides red mud, ferric ion sludge from wastewater treatment plant has also been studied for its catalytic properties, mainly due to its ferric oxide constituent. This paper reviews the studies on red mud as a catalyst. The catalyst characteristics, reaction mechanisms involved and performance are examined and compared with iron oxide catalyst and commercial catalysts. (author)
Industrial solid wastes (fly ash and red mud, a by-product of the aluminium industry) have been employed as supports for preparation of Ru-based catalysts. Physical and chemical treatments on red mud were conducted and these modified supports were also used for preparation of Ru-based catalysts. Those Ru catalysts were characterized by various techniques such as N2 adsorption, H{sub 2} adsorption, XRD, XPS, and temperature-programmed reduction (TPR), and were then tested for catalytic ammonia decomposition to hydrogen. It was found that red-mud-supported Ru catalyst exhibits higher ammonia conversion and hydrogen production than fly-ash-supported catalyst. Heat and chemical treatments of the red mud greatly improve the catalytic activity. Moreover, a combination of acid and heat treatments produces the highest catalytic conversion of ammonia. 35 refs., 4 figs., 4 tabs.
The goal of this project is to demonstrate that, by combining state-of-the-art technology, highly efficient plant operation and maintenance capabilities and by-product gypsum sales, significant reductions of SO{sub 2} emissions can be achieved at approximately one-half the life cycle cost of a conventional Flue Gas Desulfurization (FGD) system. Further, this emission reduction is achieved without generating solid waste and while minimizing liquid wastewater effluent. Basically, this project entails the design, construction and operation of a nominal 600 MWe AFGD facility to remove SO{sub 2} from coal-fired power plant flue gas at the Northern Indiana Public Service Company`s Bailly Generating Station.
It is necessary to remove chlorine efficiently from municipal waste plastics (MWP) that contain polyvinyl chloride (PVC) and other plastics containing chlorine. In this article we consider thermal degradation liquefaction technology. In Japan, the chlorine content of reclamation oil products must be kept below 100 ppm owing to the quality standard for pyrolysis oil. Liquefaction dechlorination technology for MWP is still an important issue to study. The twin-screw extruder that has been developed as dechlorination technology for blast furnaces and coke ovens has a shorter residence time for dechlorination than other dechlorination technologies. In this article, we used a single-screw extruder for the dechlorination process because it also has a short residence time. Experiments on the dech...
Counting characteristics of X-ray detectors fabricated from indium-doped, gallium-doped, and chlorine-doped CdTe have been investigated. The detectors fabricated from indium-doped and gallium-doped crystals showed radiation-induced polarization, namely, a progressive decrease of count rate with an increase of photon fluence in the high-photon-fluence region, while the detectors fabricated from chlorine-doped crystals did not. Results from current-voltage characteristics of the detectors indicated that the different counting characteristics of these detectors originated from the difference in internal electric fields in each detector.
The combustin of chloroethane is modeled as a stirred reactor so that we can study critical emission characteristics of the reactor as a function of residence time. We examine important operating conditions such as pressure, temperature, and equivalence ratio and their influence on destructive efficiency of chloroethane and production of other chlorinated products. The model uses a detailed chemical kinetic mechanism that we have developed previously for C{sub 3} hydrocarbons. We have added to this mechanism the chemical kinetic mechanism for C{sub 2} chlorinated hydrocarbons developed by Senkan and coworkers. Some reactions have been added to Senkan's mechanism and some of the reaction-rate expressions have been updated to reflect recent developments in the literature. In the modeling calculations, sensitivity coefficients are determined to find which reaction-rate constants have the largest effect on destructive efficiency. 25 refs., ...
A phenomenon based model for chlorine dioxide delignification of chemical pulp is introduced. The pulp suspension environment is modeled using the concept of two liquid phases, one inside and the other external to the fiber wall. Physico-chemical processes taking place during delignification are implemented with thermodynamic, mass transfer and reaction kinetic models. A broad library of chemical reactions is introduced. Inclusion of each reaction is justified. The model response is tested against experimental laboratory delignification results (o-delignified birch pulp). The experimental data consists of kappa number, hexenuronic acid, inorganic oxy-chlorine compound, and organochlorine (AOX, OX) measurements at several time points during five delignification experiments. The model predic...
As a result of the large limestone deposits available in Poland, the low cost of reagent acquisition for the largescale technological use and relatively well-documented processes of flue gas desulfurization (FGD) technologies based on limestone sorbent slurry, wet scrubbing desulfurization is a method of choice in Poland for flue gas treatment in energy production facilities, including power plants and industrial systems. The efficiency of FGD using the above method depends on several technological and kinetic parameters, particularly on the pH value of the sorbent (i.e., ground limestone suspended in water). Consequently, many studies in Poland and abroad address the impact of various parameters on the pH value of the sorbent suspension, such as the average diameter of sorbent particles (related to the limestone pulverization degree), sorbent quality (in terms of pure calcium carbonate [CaCO3] content of the sorbent material), stoichiometric surfeit of CaCO3 in ...
The generation of industrial solid wastes containing leachable species of environmental concern is a problem for developing and developed nations alike. These materials arise from direct processing of mineral ores, from production of metals and minerals, from manufacturing operations, and from air and water pollution treatment processes. The general characteristics that make these wastes intractable is that their content of hazardous species is not easily liberated from the waste yet is not bound so tightly that they are safe for landfill disposal or industrial use. The approach taken in this work is a thermal treatment that separates the inorganic contaminants from the wastes. The objective is to provide recovery and reuse of both the residual solids and liberated contaminants. The results from operating this technique using two very different types of waste are described. The reasons that the process will work for a wide variety of wastes are explored. By using ...
The concentration of trace elements in brain sections was measured by synchrotron radiation X-ray fluorescence. The relative concentration was calculated by means of the normalization of Compton scattering intensity approximately 22 keV, after the normalization for collecting time of X-ray spectrum and the counting of the ion chamber, and subtracting the contribution of the polycarbonate film for supporting sample. Furthermore, the statistical evaluation of the element distribution in various regions of the brain sections of the 20-day-old rats was tested. For investigating the distribution of elements in the brain of iodine deficient rats, Wistar rats were fed with iodine deficient diet and deionized water (ID group). The rats were fed the same iodine deficient diet, but drank KIO_3 solution as control (CT group). The results showed that the contents of calcium (Ca) in thalamus (TH) and copper (Cu) and iron (Fe) in cerebral cortex (CX) of ID rats were ...
The cost of liquid fuels from coal is a complex function of many factors, such as capital investment, cost of coal and labor cost. Furthermore, the cost will depend on geographical position, the size of the operation and the efficiency of the process. There is no single answer and case studies will have to be made to establish economics at different locations. In the following, the 1980 order-of-magnitude investment costs and operating costs for a coal liquefaction plant are estimated. For a Sasol II type of plant with the product output indicated earlier, the total capital cost is estimated at $4 billion in 1980 dollars. Capital cost accounts for approximately 50%, utilities and materials for 30%, and labor for 20% of the total cost. Given the market value of by-product ethylene ($175/t), tar products ($300/t), chemicals ($300/t), ammonia ($200/t) and sulfur ($25/t), the credit for by-products is $146 million per year. The cost of motor fuel ...
Field corrosion tests for a low chromium steel were carried out at a superheater area of a 100 MW pulverized coal-fired boiler for various times up to 500 h, when three coals having different chlorine contents were combusted. The low chromium steel had obvious metal loss due to corrosion, and comparison of the metal loss and corrosion scale structure was made among the three coals in respect to chlorine contents as well as other elements affecting its corrosion. Corrosion scales of the low chromium steel had a general two-layer structure: an inner layer containing iron, chromium, oxygen and sulfur, and an outer layer made of porous iron oxide and fly ash particles. Distinct molten phase formation, which is an indication of severe corrosion, was observed for the coal containing only the middle high chlorine, and it initiated in the outer layer of the corrosion scales. (author)
'The interactions of carbon tetrachloride with strongly basic oxides and hydroxides have been studied by several techniques in order to understand the surface reactions and the subsequent bulk reactions that result in the destruction of the chlorinated hydrocarbon. Emphasis has been placed on understanding the surface phases, as well as the bulk phases, that are present during these transformations. As a result of the study with barium oxide, a reaction cycle has been demonstrated that may have practical significance in the removal of chlorinated hydrocarbons.'
This paper studies the sorption of chlorine complexes of ruthenium (IV) on the graft copolymer of a polyacrylonitrile fiber with poly-2-methyl-5-vinylpyridine (PAN-MVP). The composition of the fiber is illustrated. It is shown that sorption of chlorine complexes of ruthenium (IV) from acid solutions by a pyridine fiber sorbent takes place according to an anion-exchange mechanism and is due to the formation of compounds of the diamine type (Ru(RPy)/sub 2/Cl/sub 4/).
Red mud (RM) is the main by-product of the Bayer process for alumina extraction from bauxite, and grey slurries (GS) are generated during the granite rocks transformation processes. the huge volume of those wastes generated every year suppose a serious environmental problem. Recent works by our group demonstrate the efficiency of both types of muds as corrosion inhibitors for iron and steel in alkaline media containing chlorides. The elemental analysis of these slurried shows that Al"3+ is the main common element. Therefore, the aim of this paper is to study the effect of the soluble Al"3+ in the electrochemical behaviour of iron in alkaline media, in presence and absence of chlorides. The electrochemical study using Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS) together with surface analysis techniques allowed to conclude that Al"3+ blocks the surface of steel in alkaline media chloride increasing the steel resistance to chlorides ...
Lunar resource utilization has focused principally on the extraction of oxygen from the lunar regolith. A number of schemes have been proposed for oxygen extraction from Ilmenite and Anorthite. Serendipitously, these schemes have as their by-products (or more directly as their "waste products"), materials needed for the fabrication of thin film silicon solar cells. Thus lunar surface possesses both the elemental components needed for the fabrication of silicon solar cells and a vacuum environment that allows for vacuum deposition of thin film solar cells directly on the surface of the Moon without the need for vacuum chambers. In support of the US space exploration initiative a new architecture for the production of thin film solar cells on directly on the lunar surface is proposed. The paper discusses experimental data on the fabrication and properties of lunar glass substrates, evaporated lunar regolith thin films (anti-reflect coatings and insulators), and ...
Red mud is generated as a by-product in the production of Al(OH){sub 3}/Al{sub 2}O{sub 3} from bauxite ore. In this study the pellet-type adsorbents have been made from the red mud, and their adsorption capacities of heavy metal ions have been tested. The pellet-type adsorbents were synthesized to utilize the excellent adsorption capacity of the powder-type adsorbent for industrial application. The pellet-type adsorbents were prepared by mixing several kinds of additives with the red mud. It is found that the pellet-type adsorbent, made by sintering a mixture of red mud (96.0 wt%), polypropylene (2.5 wt%), fly ash (0.5 wt%), and sodium meta-silicate (1.0 wt%) at 1200 deg.C for 30 minutes, has the highest adsorption capacity. In this work, the two kinds of pellet-type adsorbents (bead-type, crushed-type) were prepared. The crushed-type adsorbent was found to show a better adsorption/desorption performance than the bead-type adsorbent. The crushed-type adsorbent ...
Since fuel oil meeting the requirements of current petroleum products can be produced by SASOL F-T synthetic process, the manufacturing process of hydrocarbon fuel oil from the coal-derived synthesis gas, downstream processes are being successively investigated. Mobile M-gasoline, MTG, process which produces gasoline from the natural gas-derived synthesis gas through methanol went into commercial operation in New Zealand in 1986. Although the gasoline suffices the quality of commercial gasoline by both fixed bed and fluidized bed systems, the price and service life of catalyst and control of by-product durene must be improved. Any STG processes have not been completed yet and the yield and quality of gasoline are inferior to those of gasoline produced by the MTG process. Applying two-stage process, the STG process will be more economically effective.(21 refs, 4 figs, 10 tabs)
A process is described for the selective oxidation of ammonia to nitric oxide in about 90% or greater yield with a minimum of nitrogen or dinitrogen oxide (N/sub 2/O) as by-products, comprising: (1) contacting gaseous ammonia in an oxygen containing gas optionally with an inert gaseous diluent with a mixed metal perovskite catalyst of the general formula: ABO/sub 3/, wherein: A is selected from the alkali, alkaline earth, lanthanide, or actinide metals or a mixture of these metals having a relatively large ionic, radius, and B is selected from an element or a combination of elements selected from Groups IB, IVB, VB, VIB, VIIB, or VIII of the Periodic Table, wherein the perovskite phase of the catalyst has an equilibrium partial pressure of oxygen at 1000/sup 0/C of greater than about 10/sup -15/ bar; and (2) heating the reactants of step (1) at greater than about 500/sup 0/C under conditions of 10 to 100,000 hr/sup -1/ hourly space velocity.
A process is described for the selective oxidation of ammonia to nitric oxide in about 90% or greater yield with a minimum of nitrogen or dinitrogen oxide (N/sub 2/O) as by-products, comprising: (1) contacting gaseous ammonia in an oxygen containing gas optionally with an inert gaseous diluent with a mixed metal perovskite catalyst of the general formula: ABO/sub 3/, wherein: A is selected from the alkali, alkaline earth, lanthanide, or actinide metals or a mixture of these metals having a relatively large ionic, radius, and B is selected from an element or a combination of elements selected from Groups IB, IVB, VB, VIB, VIIB, or VIII of the Periodic Table, wherein the perovskite phase of the catalyst has an equilibrium partial pressure of oxygen at 1000"0C of greater than about 10/sup -15/ bar; and (2) heating the reactants of step (1) at greater than about 500"0C under conditions of 10 to 100,000 hr/sup -1/ hourly space velocity.
There are two major distinct activities involved with reprocessing of nuclear fuel. They are: a) Mechanical handling of the fuel in the head end plants; and b) chemical dissolution and separation of unused fuel, useful by-products and waste products. Plants and facilities associated with the former include significant remote handling equipment that is designed for handling of fuel for normal production processes. These equipment are selected and designed to meet the design throughput of the plant taking into consideration ease of their operation and maintenance in conjunction with statutory regulations on safety and operator dose uptake. Nevertheless, during the life of the plant, there are instances when special equipment is called for to access part of the plant and undertake tasks such as inspection, maintenance and modification to improve the existing process. BNFL has much experience in the design and application of remote handling equipment for normal ...
A nation-wide survey of natural radioactivity in building materials was conducted during 1982-1984. Samples including industrial wastes, by-products and common building materials were collected from main building material manufactories in 29 provinces except Taiwan. The results of exposure rates, specific activities and release rate for "2"2"2Rn are presented. The specific activities of common materials are listed in declining order as follows: clay bricks > common concrete and sandstones > limes and ordinary cement. The highest level was found in breeze bricks made of stone coal, phosphogypsum and red mud with high intrinsic radioactivity. Therefore, these raw materials should be strictly controlled in manufacturing building materials. The measurement results also showed that the typical specific activities of common building materials in our country were "2"2"6Ra 50 Bq/kg, "2"3"2Th 50 Bq/kg and "4"0K 500 Bq/kg. Based on the surveyed results and foreign ...
The "6"2Zn-"6"2Cu generator system is one of the few which yield a pure positron emitting daughter. The authors have developed a method for the preparation of this generator system following 32 MeV #alpha# particle bombardment of nickel targets. The chemical processing involves two stages: first a hydrous zirconium oxide column is used at pH 4-5 to separate the zinc and copper activities produced in the target nickel, and secondly, a conventional anion exchange column is used to retain the "6"2Zn and remove all copper activities in 2M HCl. This column serves as the "6"2Cu generator which will yield pure "6"2Cu repeatedly, free from "6"2Zn and other impurities, in a mixture of HCl and NaCl. A method is outlined also to obtain a solution of "6"2Zn using the hydrous zirconium oxide (HZO) column. "6"1Cu can be prepared as a by-product in the above procedure, but a method for the preparation of "6"1Cu alone using an 18 MeV #alpha# particle beam on a nickel target and ...
Numerous transmethylation reactions are required for normal plant growth and development. S-adenosylhomocysteine hydrolase (SAHH) and adenosine kinase (ADK) act coordinately to recycle the by-product of these reactions, S-adenosylhomocysteine (SAH) that would otherwise competitively inhibit methyltransferase (MT) activities. Here, we report on investigations to understand how the SAH produced in the nucleus is metabolized by SAHH and ADK. Localization analyses using green fluorescent fusion proteins demonstrated that both enzymes are capable of localizing to the cytoplasm and the nucleus, although no obvious nuclear localization signal was found in their sequences. Deletion analysis revealed that a 41-amino-acid segment of SAHH (Gly(150)-Lys(190)) is required for nuclear targeting of this enzyme. This segment is surface exposed, shows unique sequence conservation patterns in plant SAHHs, and possesses additional features of protein-protein interaction motifs. ADK ...
Developing markets in the Pacific Basin depend heavily on the production and export of consumer goods. The generation of hazardous waste as a by-product of industrial production can be linked to adverse health outcomes, such as childhood leukemia, in ways that are presently unknown. In California, exposures resulting from hazardous waste disposal are of concern in the etiology of childhood cancer. Approximately 63% of the 57 hazardous waste sites that the U.S. Environmental Protection Agency (USEPA) included in the national priority list under the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) statute were in the six-county San Francisco Bay area. This area includes California`s Silicon Valley, where a disproportionate majority of these sites are located. Although only one study links hazardous waste disposal to childhood leukemia evidence is accumulating that in utero and maternal pesticide exposures as well as chemical exposures ...
The LSND (Liquid Scintillator Neutrino Detector) experiment will be performed at LAMPF in the next several years. The main goal of the experiment is to search for {nu}{sub {mu}}-{nu}{sub e} oscillations with high sensitivity; however, an increasingly important by-product of this search is to measure {nu}p {yields} {nu}p elastic scattering and determine the strange quark contribution, {Delta}s, to the spin of the proton. With the 800-MeV proton energy of LAMPF, neutrinos are produced from pion decay-in-flight with an average energy of about 150 MeV. This energy is sufficiently high so that the {nu}p {yields} {nu}p cross section is large and is sufficiently low so that the low Q{sup 2} approximation (Q{sup 2} {much lt} m{sub p}{sup 2}) is valid and the cross section can be expressed in a simple form dependent upon {Delta}s as the only unknown. LAMPF with its 1-mA proton intensity is, therefore, an ideal accelerator to perform this measurement. 12 refs., 7 figs., 2 ...
A three-dimensional mathematical model has been developed as a tool for furnace structure design and operation conditions optimization when the straw combustion is in oxygen-enriched or conventional air atmospheres. Mathematical methods have been used based on a combination of FLIC (A fluid Dynamic Incinerator Code) code for the in-bed incineration and commercial software FLUENT for the over-bed combustion. Oxygen-enriched atmospheres promote the destruction of most pollutants due to the high oxygen partial pressures and temperatures, which is reflected by very low residual amounts of organic combustion by-products in the bottom ash and flue gas of the straw-fired boiler unit. The predictions indicated that the maximum combustion temperature is around 1500 K, CO emission is 201 vppm and O{sub 2} concentration is about 6.9 vol% at furnace exit, and it is shown that mathematical models can serve as a reliable tool for detailed analysis of straw combustion processes ...
This Public Design Report provides, in a single document, available nonproprietary design -information for the ``Innovative Coke Oven Gas Cleaning System for Retrofit Applications`` Demonstration Project at Bethlehem Steel Corporation`s Sparrows Point, Maryland coke oven by-product facilities. This project demonstrates, for the first time in the United States, the feasibility of integrating four commercially available technologies (processes) for cleaning coke oven gas. The four technologies are: Secondary Gas Cooling, Hydrogen Sulfide and Ammonia Removal, Hydrogen Sulfide and Ammonia Recovery, and Ammonia Destruction and Sulfur Recovery. In addition to the design aspects, the history of the project and the role of the US Department of,Energy are briefly discussed. Actual plant capital and projected operating costs are also presented. An overview of the integration (retrofit) of the processes into the existing plant is presented and is followed by detailed ...
In response to the Clean Coal II solicitation, Bethlehem Steel Corporation (BSC) submitted a proposal to the DOE in May 1988. The proposal submitted by BSC describes a Unique integration of commercial technologies developed by Davy/Still Otto to clean coke oven gas being produced at its Sparrows Point, Maryland steel plant. This innovative coke oven gas cleaning system combines secondary gas cooling with hydrogen sulfide and ammonia removal, hydrogen sulfide and ammonia recovery, ammonia destruction and sulfur recovery to produce a cleaner fuel gas for plant use. The primary environmental benefit associated with employing this innovative coke oven gas cleaning system is realized when the fuel gas is burned within the steel plant. Emissions of sulfur dioxide are reduced by more than 60 percent. The removal, recovery and destruction of ammonia eliminates the disposal problems associated with an unmarketable ammonium sulfate by-product. Significant reduction in ...
We evaluated the effectiveness of lime and red mud (by-product of aluminium manufacturing) to reduce metal availability to Festuca rubra and to allow re-vegetation on a highly contaminated brown-field site. Application of both lime and red mud (at 3 or 5%) increased soil pH and decreased metal availability. Festuca rubra failed to establish in the control plots, but grew to a near complete vegetative cover on the amended plots. The most effective treatment in decreasing grass metal concentrations in the first year was 5% red mud, but by year two all amendments were equally effective. In an additional pot experiment, P application in combination with red mud or lime decreased the Pb concentration, but not total uptake of Pb in Festuca rubra compared to red mud alone. The results show that both red mud and lime can be used to remediate a heavily contaminated acid soil to allow re-vegetation. - Red mud was effective in immobilising heavy metals in soil.
We evaluated the effectiveness of lime and red mud (by-product of aluminium manufacturing) to reduce metal availability to Festuca rubra and to allow re-vegetation on a highly contaminated brown-field site. Application of both lime and red mud (at 3 or 5%) increased soil pH and decreased metal availability. Festuca rubra failed to establish in the control plots, but grew to a near complete vegetative cover on the amended plots. The most effective treatment in decreasing grass metal concentrations in the first year was 5% red mud, but by year two all amendments were equally effective. In an additional pot experiment, P application in combination with red mud or lime decreased the Pb concentration, but not total uptake of Pb in Festuca rubra compared to red mud alone. The results show that both red mud and lime can be used to remediate a heavily contaminated acid soil to allow re-vegetation. - Red mud was effective in immobilising heavy metals in soil.
Biodiesel can be produced from numerous materials, including by-products of animal chain. In this scenario, the chicken's oil, that is located and an environment not explored for biodiesel production, can be a good alternative in South and Southeast Brazilian Region, where they are slaughtered around 9.100.000 chickens per day. In order to determine the specific consumption from a generator set with single cylinder 6.6 kW of power and generation capacity of 5 kW, using chicken oil biodiesel (B-100), were performed the bench test using a auxiliary tank, precision scale and an energy analyzer. Were conducted four treatments (25%, 50%, 75% and 100% of generating capacity). The worst SC was the engine at 25% of generation capacity (1.5 kW) and better with 75% of maximum load (3.75 kW) with a mean of 479.34 g kWh{sup -1}. By Turkey's test ant 5% probability there was a significant difference only for the first treatment. (author)
Red mud is a by-product of the alkaline extraction of aluminum from the bauxite and represents a renewed environmental problem due the significant annual throughput by the plants. In the present work, the pozzolanic properties of Brazilian red mud fired at 600, 700, 800 and 900 deg C were investigated by monitoring lime consumption using DTA analysis and Brazilian standard methodology NBR 5772 (1992). Products and kinetics of hydration were determined in cement pastes produced with 5 and 15% red mud using x-ray diffraction and DTA analysis. Compressive strength and capillary absorption tests were realized on mortars constituted by 5, 10 and 15% red mud in replacement of cement. When calcined at 600 deg C, the red mud develops good pozzolanic properties, and the compressive strength of mortars produced with this waste meet values in accordance with regulatory standard. These results shown than red mud can be used, in partial replacement of cement, as new ...
Red mud is a by-product of the alkaline extraction of aluminum from the bauxite and represents a renewed environmental problem due the significant annual throughput by the plants. In the present work, the pozzolanic properties of Brazilian red mud fired at 600, 700, 800 and 900 deg C were investigated by monitoring lime consumption using DTA analysis and Brazilian standard methodology NBR 5772 (1992). Products and kinetics of hydration were determined in cement pastes produced with 5 and 15% red mud using x-ray diffraction and DTA analysis. Compressive strength and capillary absorption tests were realized on mortars constituted by 5, 10 and 15% red mud in replacement of cement. When calcined at 600 deg C, the red mud develops good pozzolanic properties, and the compressive strength of mortars produced with this waste meet values in accordance with regulatory standard. These results shown than red mud can be used, in partial replacement of cement, as new ...
Red mud (Rm) is the main by-product of the Bayer process for alumina extraction from bauxite, and grey slurries (GS) are generated during the granite rocks transformation processes. the huge volume of those wastes generated every year suppose a serious environmental problem. Recent works by our group demonstrate the efficiency of both types of muds as corrosion inhibitors for iron and steel in alkaline media containing chlorides. The elemental analysis of these slurried shows that Al{sup 3}+ is the main common element. Therefore, the aim of this paper is to study the effect of the soluble Al{sup 3}+ in the electrochemical behaviour of iron in alkaline media, in presence and absence of chlorides. The electrochemical study using Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS) together with surface analysis techniques allowed to conclude that Al{sup 3}+ blocks the surface of steel in alkaline media chloride increasing the steel resistance to ...
Biodiesel is considered as an alternative fuel to Diesel fuel No. 2, which can be generally produced from different kinds of vegetable oils. Since the prices of edible vegetable oils are higher than that of Diesel fuel No. 2, waste vegetable oils and non-edible crude vegetable oils are preferred as potential low priced biodiesel sources. In addition, it is possible to use soapstock, a by-product of edible oil production, for cheap biodiesel production. In this study, a methyl ester biodiesel was produced from a hazelnut soapstock/waste sunflower oil mixture using methanol, sulphuric acid and sodium hydroxide in a two stage process. The effects of the methyl ester addition to Diesel No. 2 on the performance and emissions of a four cycle, four cylinder, turbocharged indirect injection (IDI) Diesel engine were examined at both full and partial loads. Experimental results showed that the hazelnut soapstock/waste sunflower oil methyl ester can be partially substituted ...
Industrial segments as plant of mining, hospitals and university generate considerable volumes of radioactive wastewater containing uranium. The increasing development of the use of the nuclear energy to lead away to an expansion of the sectors of the nuclear fuel cycle, but it leads to security problems and it appears the necessity of control of the removing of uranium and radioactive effluent treatments. Researches evaluate if the technique of the biosorption would promote an alternative process with attractive characteristics of cost-benefit. The residual biomass from agricultural activities has been studied and used as adsorbent of metals and organic composts by low cost, abundance and for being biodegradable. In this work, it is presented the efficiency of the coir pith for the adsorption of ions UO_2"2"+. The coir pith is a by-product of the harvest of the coconut, a renewable natural source. The study was accomplished using the batch techniques. The ...
This study addresses the solar thermal decomposition of natural gas for the co-production of hydrogen and carbon black (CB) as a high-value nano-material with the bonus of zero CO2 emission. The work focused on the development of a medium-scale solar reactor (10kW) based on the indirect heating concept. The solar reactor is composed of a cubic cavity receiver (20cm-side), which absorbs concentrated solar irradiation through a quartz window by a 9cm-diameter aperture. The reacting gas flows inside four graphite tubular reaction zones that are settled vertically inside the cavity. Experimental results in the temperature range 1740-2070K are presented: acetylene (C2H2) was the most important by-product with a mole fraction of up to about 7%, depending on the gas residence time. C2H2 content i...
Ethylen and, recently, butadiene can be epoxidized directly with oxygen and for the epoxidation of propylene, the use of heterogeneous transition metals and organic peroxides (Halcon-Process) is the major player. But, beside from those notable exceptions, all other epoxidations, including large ones like the epoxidation of plant oils as PVC-stabilizers (about 200.000 t/year), are carried out with peroxy acids. Because mcpba is far to expensive for most applications, short chain peracids like peracetic acid are used. Being much less stable than mcpba and thus risky handled in large amounts and high concentrations, these peroxy acids were preferably prepared in-situ. However, conventional in-situ formation of peracids has the serious drawback, that a strong acid is necessary to catalyze peroxy acid formation from the carboxylic acid and hydrogen peroxide. The presence of a strong acid in the reaction mixture often results in decreased selectivity because of the formation of undesired ...
Beginning in the 1940's and continuing through the 50's and early 60's, nuclear devices were tested by aerial detonation in the United States and other countries around the world. Cesium-137 (/sup 137/Cs) is one of the most important radionuclide by-products due to its abundance and slow decay (30-year half-life). The uptake of /sup 137/Cs in animal tissue is the result of its similarity to potassium. The somatic and genetic effects of /sup 137/Cs, along with its effect on reproductive cells, can pose great hazards to wildlife species. A reported buildup of /sup 137/Cs in white-tailed deer in the lower coastal plain of Georgia during the 1960's was followed by a gradual decline during the 1970's. Although numerous studies have involved terrestrial mammals of Georgia, few have involved aquatic mammals such as the river otter. With continued atmospheric testing by some foreign countries and the increased use of nuclear ...
The aim of this paper is to investigate the possible displacement of natural gypsum (CaSO{sub 4}2H{sub 2}O) in cement with an alternative setting retarder, such as the industrial by-product derived from flue gas desulfurization process called FGD gypsum. These calcium-sulfate-bearing materials (CSBM), alone or in mixtures, were ground with clinker both in laboratory and industrial scale to examine their influence on the physical and mechanical properties of cement, as well as on the industrial production line of cement. From the present work, it is extracted that the use of mixtures of sulfate-bearing materials with gypsum seems to be advantageous for the actual control of setting time. The addition of FGD gypsum increases setting time without affecting compressive strength profile. During the industrial trial, the formation of hemihydrate form of calcium sulfate dihydrate has a profound regulatory effect on the setting and strength performance of the cement ...
The AFGD process as demonstrated by Pure Air at the Bailly Station offers a reliable and cost-effective means of achieving a high degree of SO{sub 2} emissions reduction when burning high-sulfur coals. Many innovative features have been successfully incorporated in this process, and it is ready for widespread commercial use. The system uses a single-loop cocurrent scrubbing process with in-situ oxidation to produce wallboard-grade gypsum instead of wet sludge. A novel wastewater evaporation system minimizes effluents. The advanced scrubbing process uses a common absorber to serve multiple boilers, thereby saving on capital through economies of scale. Major results of the project are: (1) SO{sub 2} removal of over 94 percent was achieved over the three-year demonstration period, with a system availability exceeding 99.5 percent; (2) a large, single absorber handled the combined flue gas of boilers generating 528 MWe of power, and no spares were required; (3) direct injection of ...
Background: The environment preferred by Acanthamoeba trophozoites and the mechanism by which the amebae enters the cornea are not yet fully understood. A better understanding of the pathogenesis of this disease may help with prevention and treatment. Purpose: To define the preferred environments for Acanthamoeba survival and proliferation in vitro by examining the effect of tonicity, nutrient concentration, and free chlorine content on Acanthamoeba. Materials and methods: Human corneal isolates of Acanthamoeba castellanii and Acanthamoeba polyphaga trophozoites were cultured at 22^oC (room temperature) in PYG (peptone-yeast extract-glucose) medium. The effect of tonicity on amebae was determined by incubating trophozoites in sodium chloride solutions in concentrations ranging from 0% to 1...
IntroductionThe elimination of microorganisms from the root canal system necessitates the use of combination of irrigating solutions to enhance their antimicrobial property. The combination of irrigants and their interaction sometimes could be detrimental to the outcome of the root canal therapy. The purposes of this study were (1) to evaluate the interaction between 7% maleic acid (MA) and 2% chlorhexidine gluconate solution (CHX) and to find out the availability of individual irrigant and (2) to determine the free available chlorine content when 7% MA was mixed with 2.5% sodium hypochlorite (NaOCl) solution. MethodsInteraction between MA and CHX was assessed by high-performance liquid chromatography. Available chlorine content in NaOCl was evaluated by the standard iodine/thiosulfate tit...
This paper examines cupric chloride solid conversion during hydrolysis in a thermochemical copper-chlorine (Cu-Cl) cycle for hydrogen production. The hydrolysis reaction is a challenging step, in terms of the excess steam requirement and the decomposition of cupric chloride (CuCl_2) into cuprous chloride (CuCl) and chlorine (Cl_2). The hydrolysis and decomposition reactions are analyzed with respect to the chemical equilibrium constant. The effects of operating parameters are examined, including the temperature, pressure, excess steam and equilibrium conversion. A maximization of yield and selectivity are very important. Rate constants for the simultaneous reaction steps are determined using a uniform reaction model. A shrinking core model is used to determine the rate coefficients and predict the solid conversion time, with diffusional and reaction control. These new results are useful for scale-up of the engineering equipment in the ...
Co-combustion tests for recycled fuels and peat were made at a 15 kW fluidized bed reactor at VTT Energy in Jyvaeskylae. Peat was used as reference fuel. 25 tests in total were performed during 1994 - 1996. A part of the peat energy was substituted by coal in five tests, in order to change the sulphur/chlorine ratio of the fuel mixture. Fuel mixtures (25% recycled fuel and 75% peat, at energy ratio) were pelletized in order to get homogeneous fuel mixtures. The tests in the year 1994 were air staging experiments (with and without tertiary air). All test were performed with air staging in the years 1995 and 1996. The aim of the research was to determine whether the co-combustion of waste materials will cause additional emission problems, as compared to combustible emissions from conventional air-staged fluidized bed combustion. Further, the aim was to study which large-volume components can be burned safely. One aim was to study the influence of fuel properties and ...
The chemical reaction between nitric acid and sodium chloride was investigated in onder to provide preliminary information for subsequent studies on the interaction between simulated Purex waste solution and salt. The reaction is characterized by the production of chlorine and nitrosyl chloride and can be considered to be the same as the aqua regia reaction. Within the limits of the conditions imposed by the projected field studies, the acid concentration and temperature are the two parameters which control the extent of the interaction. (auth)
γ-Hexachlorocyclohexane (γ-HCH) is one of several highly chlorinated insecticides that cause serious environmental problems. The cellular proteins of a γ-HCH-degrading bacterium,...Full Text Available
The synthesis of novel b-functionalized derivatives of the clinically used photosensitizer Temoporfin has been achieved by nucleophilic addition reactions to a corresponding diketo chlorin. The b-substituted dihydroxychlorin products exhibit a strong absorption in the red spectral region, a high singlet oxygen quantum yield, and were found to be highly effective in in vitro assays against HT-29 tumor cells.
The disposition of three (1-/sup 14/C)-chlorododecanes (MCDD, PCDD I and PCDD II; 17.4%, 55.9%, and 68.5% chlorination) was studied in C57Bl mice. (1-/sup 14/C)-lauric acid (LA) was studied as reference compound. Fifty-two percent (MCDD), 32% (PCDD I), and 8% (PCDD II) of the radioactive doses were exhaled as /sup 14/CO/sub 2/ during 12 h after i.v. injection. Similar results were obtained after p.o. administration. In addition to a marked labelling of the liver and fat, the distribution patterns observed at 24 h after administration revealed an uptake of radioactivity in tissues with high cell turnover/high metabolic activity, e.g., intestinal mucosa, bone marrow, salivary glands and thymus. The concentration of radioactivity in these sites and the exhalation of /sup 14/CO/sub 2/, which were inverse to the degree of chlorination, indicate that the chloroalkanes are degraded to metabolites which can be utilized in the intermediary metabolism. A ...
Lysozyme, ethylenediaminetetracetic acid, chlorine, x-irradiation and microwaves were used in experimental attempts to eliminate Salmonella senftenberg 775W or Salmonella typhimurium from turkey drumsticks and whole carcasses. Turkey drumsticks or whole carcasses were artificially contaminated with S. senfenberg 775W or S. typhimurium in concentrations ranging between 5 x 10"5 to 8 x 10"5 viable cells per ml. of contaminating fluid. After each treatment, samples were cultured, plated, and tested according to standard methods to determine the susceptibility of Salmonella organisms to the particular treatment. A 0.1 percent solution of lysozyme eliminated the S. senftenberg 775W at 22"0C within three hours. A 0.5 percent solution of ethylenediaminetetracetic acid failed to destroy the test organism under the same conditions. Eighty thousand rads of X-ray eliminated the test organism on turkey drumsticks but failed to remove it from whole turkey carcasses. Microwaves ...
The α-proteobacterial strain Sphingobium japonicum UT26 utilizes a highly chlorinated pesticide, γ-hexachlorocyclohexane (γ-HCH), as a sole source of carbon...Full Text Available
Clean Water Act You are here: Water Laws & Regulations Policy & Guidance Clean Water Act Water Quality and 401 Certification Water Quality and 401 Certification Water Quality...
Programs & Services Technical Resources Land Use Soils Water Snow Survey & Water Supply Water Management Water Quality Watersheds Wetlands Air Plants & Animals Energy Climate...
The naive time reversal odd (T-odd) parton distribution $h_{1}^{\\perp}$, the so-called Boer-Mulders function, for both $u$- and $d$-quarks is considered in the diquark spectator model. While other approaches give evidence that the signs of the Boer-Mulders function for both flavors $u$ and $d$ are the same and negative, previous caculations in the diquark-spectator model found $h_{1}^{\\perp(u)}$ and $h_{1}^{\\perp(d)}$ have differnet signs. The flavor dependence is of significance for the analysis of the azimuthal $\\cos(2\\phi)$ asymmetries in unpolarized SIDIS and DY-processes, as well as for the overall physical understanding of the distribution of transversely polarized quarks in unpolarized nucleons. We find substantial differences with previous work. In particular we obtain estimates of the zeroth, half and first moments of Boer-Mulders functions that are negative over the full range in Bjorken $x$ for both the up and down quarks. In conjunction with the Collins function we ...
The strategy for building SASOL plants reflects a commitment to long-range planning. The first plant, which represented a large investment for a moderate production capacity, was built to establish a technology for reducing South Africa's dependence on imported motor fuels. After the success of the plant, SASOL made plans for a larger plant, which had to be justified solely on economic grounds. At that time, petroleum crude was cheap and plentiful, and the second plant was cancelled. But when OPEC formed and the price of petroleum crude was increased, the South African government reconsidered the plans for another SASOL plant. Furthermore, because the cost of fuels produced at Sasol I proved to be significantly insensitive to inflation and future OPEC price increases were expected, SASOL projected that a new, larger plant should make a profit within a few years after its initial operation. But OPEC prices and inflation have risen even faster than anticipated, and the products ...
The strategy for building SASOL plants reflects a commitment to long-range planning. The first plant, which represented a large investment for a moderate production capacity, was built to establish a technology for reducing South Africa's dependence on imported motor fuels. After the success of the plant, SASOL made plans for a larger plant, which had to be justified solely on economic grounds. At that time, petroleum crude was cheap and plentiful, and the second plant was cancelled. But when OPEC formed and the price of petroleum crude was increased, the South African government reconsidered the plans for another SASOL plant. Furthermore, because the cost of fuels produced at Sasol I proved to be significantly insensitive to inflation and future OPEC price increases were expected, SASOL projected that a new, larger plant should make a profit within a few years after its initial operation. But OPEC prices and inflation have risen even faster than anticipated, and the products ...
In the present work, the introduction of alternative energy of biogas in agricultural communities for the sustainable development was studied through exploitation of residual biomass and also getting as by-product the biological fertilizer. A fast composting of the domestic residue with the organic was made possible where part of this residue after processing was taken together with effluent to the biodigester. The bibliographical research on the processes of generation of biogas, about composting and the equipment for processing had been carried through. The projects engineering with the use of computational tools had been developed with the software Super Pro 4,9 Design and ORC GPEC 2004 by our research group. Five case studies had been elaborated, where different scenes related with our innovation, that uses of the residue for the composting together with domestic effluent for digestion. Several economic parameters were obtained and our work proved the viability ...
Only about 25% of residue accumulating in the Federal Republic of Germany is currently used for the purposes of energy. This residue will be converted into fuel for power stations by the Omega process when the dumping of waste with a calorific value in excess of 5 MJ/kg is prohibited with effect from 2005. This oxygen melting process is suitable for the local use of substitute fuels. Waste is converted into a high-quality synthesis gas with a wide range of uses. The Omega process combines drying, thermal decomposition, gasification and melting of the material used in a single-stage process. This is now technologically possible for the first time by combining a metallurgical cupola furnace with a traditional gas producer. The highly-calorific synthesis gas produced by the Omega process can be used in block heat and power stations or as an industrial fuel gas, instead of natural gas. It is also suitable as a starting material for synthesising methanol. The gas is specifically processed ...
Once again Brazil faces the possibility of an electricity shortage in the near future. The low level of rain and the consequent reduction of hydroelectric reservoirs (hydroelectric energy represents almost 80% the total Brazilian electricity generation) led to the dispatch of thermal plants based on natural gas and/or fuel oil. However, the recent crisis regarding the Bolivian natural gas supply to Brazil increased the risk of a shortage of this energy source. Hence, the uncertainty of the electricity supply scenario is pushing the electricity prices up in the near future. A possible alternative to increase the electricity supply is the maximization of the electricity surplus in sugarcane mills. Back in 1970's and 1980's, cogeneration plants in sugarcane mills were primarily designed to consume all bagasse, and produce steam and electricity to the process. The plants used medium pressure steam boilers (21 bar and 300 deg C) and back pressure steam turbines. Some ...
Cereal straw, a by-product in the production of agricultural crops, is considered as a potentially large source of energy supply with an estimated value of 47 x 10{sup 18} J worldwide. However, there is some debate regarding the actual amounts of straw which could be removed from arable soils without jeopardizing their quality, as well as the potential trade-offs in the overall straw-to-energy chain compared to the use of fossil energy sources. Here, we used a deterministic model of C and N dynamics in soil-crop systems to simulate the effect of straw removal under various sets of soil, climate and crop management conditions in northeastern France. Model results in terms of nitrate leaching, soil C variations, nitrous oxide and ammonia emissions were subsequently inputted into the life-cycle assessment (LCA) of a particular bio-energy chain in which straw was used to generate heat and power in a plant producing bio-ethanol from wheat grains. Straw removal had ...
The 1.7 billion pounds of benzene produced each year in the US provide one measure of its utility. At the same time, there are a number of environmental reasons for avoiding the use of benzene in chemical manufacture. Perhaps most compelling: benzene is a potent carcinogen. Scrutiny of many of the chemicals derived from benzene reveals that each molecule contains at least one oxygen atom while benzene completely lacks oxygen atoms. Introduction of oxygen to make up for this lack can require processes that are environmentally problematic. One of the steps used to introduce oxygen atoms during manufacture of adipic acid, a component of Nylon 66, is responsible for 10% of the annual global increase in atmospheric nitrous oxide. This by-product is a causative agent of atmospheric ozone depletion and has been implicated in global warming. With support from EPA and the National Science Foundation, alternative manufacturing processes are being explored. By these new ...
It was shown by Gibbons and Tsarev (1996 Phys. Lett. A 211 19, 1999 Phys. Lett. A 258 263) that N-parameter reductions of the Benney equations correspond to particular N-parameter families of conformal maps. In recent papers (Baldwin and Gibbons 2003 J. Phys. A: Math. Gen. 36 8393-417, Baldwin and Gibbons 2004 J. Phys. A: Math. Gen. 37 5341-54), the present authors have constructed examples of such reductions where the mappings take the upper half p-plane to a polygonal slit domain in the #lambda#-plane. In those cases, the mapping function was expressed in terms of the derivatives of Kleinian #sigma# functions of hyperelliptic curves, restricted to the one-dimensional stratum #THETA#_1 of the #THETA#-divisor. This was done using an extension of the method given in Enolskii et al (2003 J. Nonlinear Sci. 13 157) extended to a genus 3 curve (Enolski V Z and Gibbons J Addition theorems on the strata of the theta divisor of genus three hyperelliptic curves, in preparation). Here, we use ...
Full text: Based on experience with nuclear material confiscated in Hungary from illicit trafficking activities in the nineties it has been decided that traditional gamma-spectrometry should be complemented by destructive analytical techniques. The 17/1996 (I. 31.) Korm. Governmental Decree delegated the identification, categorization and characterization tasks to the Institute of Isotopes, Budapest. Routine gamma-spectrometric methods have been further developed aiming at the i) age (production date) determination of seized samples and complete (nondismountable) uranium-bearing items (such as fresh fuel bundles and fission chambers) by HRGS technique, ii) improvement of measurement accuracy and reliability. Starting in 2005 mass spectrometry (ICP-SFMS) and scanning electron microscopy have been implemented to characterize nuclear samples in more detail and to analyze environmental samples both for isotopic and elemental composition focusing on long-lived radioactive isotopes including ...
In the present work, the introduction of alternative energy of biogas in agricultural communities for the sustainable development was studied through exploitation of residual biomass and also getting as by-product the biological fertilizer. A fast composting of the domestic residue with the organic was made possible where part of this residue after processing was taken together with effluent to the biodigestor. The bibliographical research on the processes of generation of biogas, about composting and the equipment for processing had been carried through. The projects Engineering with the use of computational tools had been developed with the Software Super Pro 4,9 Design and ORC GPEC 2004 by our research group. Five case studies had been elaborated, where different scenes related with our innovation, that uses of the residue for the composting together with domestic effluent for digestion. Several economic parameters were obtained and our work proved the viability ...
Fully fluorinated compounds (perfluoro compounds) represent a class of chemicals which include many extremely inert species-inert to both chemical reaction and photodissociation. Well known examples include SF6 and the perfluorocarbons (PFCs) CF_4 and Teflon. SF_6 is used industrially in electrical switch gear and as an atmospheric tracer. CF_4 and C_2F_6 are released into the atmosphere as a by-product of aluminum manufacture. Several perfluoro compounds have been proposed as substitutes for the ozone-destroying Freons and halons; proposed substitutes include SF_6, c-C_4F_8, C_5F_1_2, and C_6F_1_4. These chemicals were chosen in part because they do not harm the stratospheric ozone layer and were therefore considered environmentally friendly. Recently, Ravishankara et al. reported that perfluoro compounds have significant global warming potential (GWP), contributing to the greenhouse effect due to strong infrared absorption. The perfluoro compounds have ...
A study was conducted to determine the impacts of climate change on the transportation sector in a regional context. The purpose was to analyze potential climate change impacts on demand for freight transportation in Atlantic Canada through its association with other sectors of the regional economy. Freight transportation is designed to meet transportation demands of commodity producers who must deliver their goods to final users. Since it is a by-product of profit maximization and cost minimization by producers of all types of commodities in various sectors of the economy, this study modelled climate change impacts as productivity shocks in relevant sectors of the economy. A computerized simulation was then used to determine how the consequences of these shocks influence the demand for freight transportation. This was accomplished by collecting climate related data in Atlantic Canada as well as aggregate economic data that reflects the economic performance of the ...
Composting is one of the waste disposal methods adopted for disposal of livestock waste in Hong Kong. The composting livestock waste normally undergoes 6-8 weeks fermentation, followed by 16-20 weeks maturation. The matured compost is sold as soil conditioner in the local market. In 2006, feedstock material and a time-series of compost samples were collected throughout the fermentation and maturation process from the Sha Ling Composting Plant in the New Territories. The feedstock material and compost samples were analyzed for contents of three unintentional persistent organic pollutants (POPs), i.e. dioxins/furans, dioxin-like PCBs and total PCBs. These POPs are unintentionally produced by-products of chemical industrial processes and combustion processes. Selected heavy metals were also analyzed, which served as conservative tracers to determine potential mass loss during the composting process. Levels of contamination by these POPs were found to be low in the ...
MnO2 in pyrolusite can react with SO2 in flue gas and obtain by-product MnSO4 x H2O. A pilot scale jet bubbling reactor was applied in this work. Different factors affecting both SO2 absorption efficiency and Mn2+ extraction rate have been investigated, these factors include temperature of inlet gas flue, ration of liquid/solid mass flow rate (L/S), pyrolusite grade, and SO2 concentration in the inlet flue gas. In the meantime, the procedure of purification of absorption liquid was also discussed. Experiment results indicated that the increase of temperature from 30 to 70 K caused the increase of SO2 absorption efficiency from 81.4% to 91.2%. And when SO2 concentration in the inlet flue gas increased from 500 to 3000 ppm, SO2 absorption efficiency and Mn2+ extraction rate decreased from 98.1% to 82.2% and from 82.8% to 61.7%, respectively. The content of MnO2 in pyrolusite had a neglectable effect on SO2 absorption efficiency. Low L/S was good for both removal of ...
Two 40 MWe Ocean Thermal Energy Conversion (OTEC) Pilot Plant programs are in the initial phase of development near Kahe Point, Oahu, Hawaii. The two options being examined are: (1) a shelf-seated artificial island, connected via a causeway to Oahu, using stainless steel heat exchangers, with the thermal resource enhanced by effluent from a near-by power plant, ammonia working fluid and biocide (chlorine) cleaning; and (2) a shelf mount tower 1 mile off shore using submerged aluminum heat exchangers, R-22 working fluid, and slurry cleaning with biocide (chlorine) backup. Environmental Technical Requirements are described including: siting criteria; environmental design, and operational criteria; thermal resource evaluation and variability; physical, chemical, and biological data requirements; and regulatory requirements. Due to siting, design, and operational differences the proposed two pilot plant options have individual environmental ...
The aim of this study was to investigate the photodegradation of the antiemetic drug metoclopramide. Metoclopramide aqueous solutions were photoirradiated at 254nm under argon atmosphere. Irradiated metoclopramide solutions were analyzed by high performance liquid chromatography-ion trap mass spectrometry in order to characterize photolysis products. Rapid decrease in metoclopramide purity, following first-order kinetic, was observed following irradiation. The structures of 18 photolysis products were tentatively identified based on their mass spectra and fragmentation. The main degradation mechanism was scission of the chlorine which could be followed by polymerization of the resulting products since dimeric and trimeric products were observed.
Experiments were conducted which established that the higher passivating capacity of Ni/sub 60/Nb/sub 40/ alloys in the amorphous state and higher efficiency of the anodic process of generation of chlorine (2 N NaCl + HCl to pH = 0) in comparison with the crystalline state are determined by higher homogeneity and density of the passive films formed on the amorphous alloy and by higher electron conduction which depends directly on the difference in the structure of the passive films formed on the alloys in the amorphous and crystalline states.
Since the Scientific Assessment of Ozone Depletion: 1998, numerous laboratory investigations, atmospheric observations, and theoretical and modeling studies have produced new key findings and have strengthened overall understanding of the ozone layer and its effect on ultraviolet (UV) radiation. These advances are highlighted in the following summary of the current understanding of the impact of human activities and natural phenomena on the ozone layer and the coupling of the ozone layer and the climate system. In the troposphere (i.e., lower atmosphere), observations show that the total combined effective abundance of ozone-depleting compounds continues to decline slowly from the peak that occurred in 1992-1994. Total chlorine is declining, while bromine from industrial halons is still increasing, albeit at a slower rate than was occurring previously (and as reported in the 1998 Assessment). Analyses of air trapped in snow since the late 19th century have ...
The reaction of uranium oxides and chlorine to prepare anhydrous uranium tetrachloride (UCl{sub 4}) are important to more economical preparation of uranium metal. The most practical reactions require carbon or carbon monoxide (CO) to give CO or carbon dioxide (CO{sub 2}) as waste gases. The chemistry of U-O-Cl compounds is very complex with valances of 3, 4, 5, and 6 and with stable oxychlorides. Literature was reviewed to collect thermochemical data, phase equilibrium information, and results of experimental studies. Calculations using thermodynamic data can identify the probable reactions, but the results are uncertain. All the U-O-Cl compounds have large free energies of formation and the calculations give uncertain small differences of large numbers. The phase diagram for UCl{sub 4}-UO{sub 2} shows a reaction to form uranium oxychloride (UOCl{sub 2}) that has a good solubility in molten UCl{sub 4}. This appears more favorable to good rates of reaction than ...
Most of the synthetic gypsum generated from wet flue gas desulfurization (FGD) scrubbers is currently being used for wallboard production. Because oxidized mercury is readily captured by the wet FGD scrubber, and coal-fired power plants equipped with wet scrubbers desire to benefit from the partial mercury control that these systems provide, some mercury is likely to be bound in with the FGD gypsum and wallboard. In this study, the feasibility of identifying mercury species in the FGD gypsum and wallboard samples was investigated using a large sample size thermal desorption method. Potential candidates of pure mercury standards including mercuric chloride (HgCl2), mercurous chloride (Hg2Cl2), mercury oxide (HgO), mercury sulfide (HgS), and mercuric sulfate (HgSO4) were analyzed to compare their results with those obtained from FGD gypsum and dry wallboard samples. Although any of the thermal evolutionary curves obtained from these pure mercury standards did not exactly match with those ...
The present work mainly involves bench scale studies to investigate partitioning of mercury in pulverized fuel co-combustion at 1000 and 1300{sup o}C. High volatile bituminous coal is used as a reference case and chicken manure, olive residue, and B quality (demolition) wood are used as secondary fuels with 10 and 20% thermal shares. The combustion experiments are carried out in an entrained flow reactor with a fuel input of 7-8 kWth. Elemental and total gaseous mercury concentrations in the flue gas of the reactor are measured on-line, and ash is analyzed for particulate mercury along with other elemental and surface properties. Animal waste like chicken manure behaves very differently from plant waste. The higher chlorine contents of chicken manure cause higher ionic mercury concentrations whereas even with high unburnt carbon, particulate mercury reduces with increase in the chicken manure share. This might be a problem due to coarse fuel particles, low surface ...
for? Learn the Issues Science & Technology Laws & Regulations About EPA Contact Us Water: Water Quality Criteria You are here: Water Science & Technology Surface Water Standards &...
The objective of this project was to develop new photocatalytic or other innovative process chemistry for the treatment of pink water and related contaminated water.
Reaction Engineering International (REI) has established a project team of experts to develop a technology for combustion systems which will minimize NO x emissions and minimize carbon in the fly ash. This much need technology will allow users to meet environmental compliance and produce a saleable by-product. This study is concerned with the NO x control technology of choice for pulverized coal fired boilers, ?in-furnace NO x control,? which includes: staged low-NO x burners, reburning, selective non-catalytic reduction (SNCR) and hybrid approaches (e.g., reburning with SNCR). The program has two primary objectives: 1) To improve the performance of ?in-furnace? NO x control processes. 2) To devise new, or improve existing, approaches for maximum ?in-furnace? NO x control and minimum unburned carbon. The program involves: 1) fundamental studies at laboratory- and bench-scale to define NO reduction mechanisms in flames and reburning jets; 2) laboratory experiments ...
Serotonin is one of the neurotransmitters found in the brain and mediates brain functions. It is very well known that serotonin related brain abnormalities are exerted mainly via serotonin receptors in a similar manner to other neurotransmitters found in the brain. Recently, it has also been found that serotonin is involved in Alzheimer's disease either directly or indirectly by its actions on serotonergic neurons. To understand and treat the diseases caused by abnormalities in the serotonergic system in the brain, it is certain that its mechanism of function has to be well investigated. So far several 5-HT receptors and receptor subtypes have been well characterized. Moreover, serotonin agonists and antagonists acting on specific receptors are chemically synthesized and are now available for the prevention or treatment of serotonergic related diseases. In recent years, a great demand for developing neuroimaging agents has emerged for the diagnosis of abnormal brain functions in the ...
Volume 2 of the water resources data for the 1992 water year for Oklahoma consists of record of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes or reservoirs; and water levels of ground-water well. The report contains discharge records for 136 gaging stations; stage and contents for 31 lakes or reservoirs; water quality for 50 gaging stations. Also included are 61 partial-record or miscellaneous streamflow stations and 28 ground-water sites.
The depletion of stratospheric ozone is caused by chlorine species formed in heterogeneous processes on the surfaces of polar stratospheric cloud (PSC) particles. For studying local PSC formation processes in the Arctic a temperature lidar receiver was developed that makes use of the rotational Raman method, the only lidar technique for measuring atmospheric temperature profiles not perturbed by the presence of aerosols or cloud particles. The receiver was implemented in the mobile GKSS Raman lidar and transferred to Esrange (67.9 N, 21.1 E) near Kiruna in northern Sweden in winter 1997/98. Temperature data measured between January 22 and February 6, 1998, are presented and compared to model data analyzed by the European centre for medium-range weather forecast. Local temperature profiles are studied in three cases of type-Ib PSCs. This type is characterized by a low depolarization ratio. (orig.)
Ion beams of halogens can be produced either positively or negatively charged, depending on the employed ion source. At CERN-ISOLDE, although positively charged fluorine and astatine can be obtained from a hot plasma ion source, they are often contaminated by isobars and molecular sidebands. This has generated a request from the scientific community for fluorine and astatine negative ion beams free of contaminants. The high selectivity ensured by the surface ionisation process also makes negative beams of chlorine, bromine and iodine highly attractive. However, the efficiency figures for negative surface ionisation of fluorine and astatine were lower than the ones from the hot plasma. Here we report our R and D on new surface ion sources suitable for the production of negative halogen beams.
The kinetics of the reaction of 2,4-dinitrohalogenobenzenes (chlorine, bromine, and iodine derivatives) with tetraethylammonium azide in acetonitrile and in a mixed acetonitrile-dioxane solvent (80 vol. % dioxane) were studied. It was established that there is a marked increase (by more than three orders of magnitude) in the azidization rate constant in the transition from protic solvents to aprotic media, due to the decrease in the activation energy barrier of the reaction. The nucleophilicity parameters N/sup +/ for the azide ion in the investigated solvents were determined in terms of Ritchie's relationship. It was established that the effect of the nature of the leaving group on the rate constant of the reactions is complex in character, and it was shown that treatment of the relative reactivity series for the investigated substrates must be based on an analysis of the activation parameters and not restricted to data obtained at only one temperature.
The structure of nano-porous carbon, obtained by means of chlorination of carbide compounds with various crystal structure (SiC, TiC, Mo_2C) is studied through the method of small-angle diffraction. The angular dependences of the scattering intensity obtained are interpreted as the result of scattering from the nanoparticles of different size. The functions of the scattering particles distribution by the m(R_g) inertia radii are determined. It is shown that in spite of the source carbide, the highest fraction of the volume in the porous carbon constitute the particles with R_g #approx# 5 A. The nanoparticles in the samples obtained from SiC, wherein the average value of the R_g"a"v < 6 A, are most uniform by size. The nanoparticles in the porous carbon, obtained from Mo_2C, are on the average by two times larger
The electrochemical behaviour and fracture morphology of homogenized and sensitized type SAE 304 stainless steel U bent specimens, in 3% NaCl solution, at pH=2.0 and pH=7.0 both at room temperature and 100"0C was studied. Polarization curves, galvanostatic and potentiostatic experiments were run. It could be observed that high temperature and low pH favour transgranular cracking and longer sensitization times lower fracture time and tend to give rise to intergranular fracture. Light sensitization can produce transgranular cracking even at room temperature, when the homogenized alloy does not present stress-corrosion cracking for the same condition. (Author).
Abstract Flame retardants (FRs) are used for in protection against fire. Organic inorganic hybrids could become one of the most promising FR solution in the future. In this paper, the synthesis, the characterization and the use as FRs and filler of grafted titania and alumina with 2 chloroethylphosphonic acid are presented. These hybrids contain 3.8 3.24% P and have good flame retardance when they are incorporated into unsaturated polyester resins. Alumina treated with 2 chloroethylphosphonic acid performed better than titania. The advantage of this approach is the use of these hybrid materials as filler and FR, in the same time, and the increase in flame retardancy by synergistic effect between alumina phosphorus and chlorine, for unsaturated polyester resins. Copyright 2010 John Wiley & ...
Abstract The characteristics of desulfurization and denitrification with composite absorbent were researched through aqueous absorption experiments. The removal efficiencies of SO2 and NO were up to 100 and 95%, respectively. The composite absorbent included NaClO2 and component M. Existence of component M in the solution could reduce the absorbent cost compared with using sodium chlorite alone. Chlorine dioxide, as main reaction intermediate product, participated in oxidation reaction. The optimal experimental conditions involved NaClO2 concentration of1.13 mmol/L, solution pH of 5.5, molar ratio (M/NaClO2) of 4.1, reaction temperature of 323 K. The optimal solution pH and reaction temperature were both in the required ranges of limestone-gypsum wet flue gas desulfurization (FGD) process....
During earlier work rapid and highly sensitive Jet-REMPI (resonance-enhanced multiphoton ionization) mass spectrometry was applied for monitoring the effluent from thermal treatment of a filter dust during a de novo test under laboratory conditions. The sample, from ESP-Field 2 of an iron ore sintering plant, was already loaded with dioxins ({sigma}PCDD/F = 132 ng/g), their precursors (PCBz, PCPh) and other products of incomplete combustion. Heating filter dust in a temperature window 200-350 C under a flow of air results in further formation of these pollutants. As described elsewhere, on-line detection was mostly carried out using a non-selective ionization mode, to measure a wide range of compounds simultaneously. The changes of output suggest that the reaction products increase in chlorination level with time. Another explanation is that higherchlorinated compounds appear later as a consequence of lower volatility and stronger adsorption. However, due to mass ...
Microbial dechlorination of polychlorinated biphenyls (PCBs) often stops although a significant number of removable chlorines remain. To determine the reason for the cessation, we investigated the limitation of organic carbon, PCB bioavailability, and inhibition by metabolic products. Enrichment with carbon sources did not induce additional chlorination, indicating the plateau was not due to depletion of organic carbon. The bioavailability was not limiting, since a subcritical micelle concentration of the surfactant, which enhanced desorption without inhibiting dechlorinating microorganisms, failed to lower the plateau. Neither was it due to accumulation of metabolites, since no additional dechlorination was detected when plateau sediments were incubated with fresh medium. Similarly, dechlorination was not inhibited in freshly spiked sediment slurries. Dechlorination ended up at the same level with nearly identical congener profiles, regardless ...
This study investigated the influence of different charge typologies and additives on the PCDD/Fs amount produced and on the congener profiles in an iron ore sintering plant. Many tests were carried out combining different typologies of charge (iron materials) and solid fuel ('coke breeze' or 'anthracite') with or without the use of urea. The PCDD/Fs produced ranged from 1.2 to 22.7 {mu} g I-TEQ/ton of agglomerate, whereas the PCDD/Fs released to the ambient air ranged from 0.10 to 1.92 ng I-TEQ/Nm{sup 3} because of cleaning in an electrostatic precipitator (ESP) and a Wetfine scrubber (WS). A more homogeneous charge with a higher amount of fine particles charge appeared to produce a lower PCDD/Fs concentration due to a better combustion but this hypothesis needs further investigations on charges having different dimension particles. Only a synergitic action of urea and anthracite was able to reduce the high PCDD/Fs content due to the bad combustion ...
The eastern oyster (Crassostrea virginica) developed neoplastic disorders when experimentally exposed both in the laboratory and field to chemically contaminated sediment from Black Rock Harbor (BRH), Bridgeport, Connecticut. Neoplasia was observed in oysters after 30 or 60 days of continuous exposure in a laboratory flow-through system to a 20 mg/L suspension of BRH sediment plus postexposure periods of 3, 30, or 60 days. Composite tumor incidence was 13.6% for both exposures. Tumor occurrence was highest in the renal excretory epithelium, followed in order by gill, gonad, gastrointestinal, heart, and embryonic neural tissue. Regression of experimental neoplasia was not observed when the stimulus was discontinued. In field experiments, gill neoplasms developed in oysters, deployed in cages for 30 days at BRH and 36 days at a BRH dredge material disposal area in Central Long Island Sound, and kidney and gastrointestinal neoplasms developed in caged oysters deployed 40 days in Quincy ...
Described herein are the results of the FY1994 research program for analysis and evaluation for thin film solar cells. The study on quantitative analysis of hydrogen atoms in a plasma determines quantity of hydrogen atoms in the plasma of monosilane diluted with hydrogen. It is found, contrary to expectation, that quantity of hydrogen atoms in the plasma decreases as it is more diluted with hydrogen. The study on light-induced degradation of the thin chlorine-base amorphous silicon films confirms that the plasma CVD method with 20% of dichlorosilane gas added to monosilane gas produces the thin amorphous silicon film 3 times faster than the conventional method. The thin film has essentially the same defect density as the one prepared by the conventional method, showing good photoelectric characteristics. The thin film of chlorinated amorphous silicon has a 1 digit lower defect density than the conventional one of amorphous silicon, as revealed ...
Water-resources data for the 1993 water year for Minnesota consists of records of stage, discharge and water quality of streams; stage, contents, and water quality of lakes and reservoirs; and water levels and water quality in wells and springs. This volume contains discharge records for 58 gaging stations; stage and contents for 9 lakes and reservoirs; water quality 15 stream stations, 1 lakes station, 1 precipitation station, and water levels for 15 observation wells. Also included are 61 high-flow partial-record stations. Additional water data were collected at various sites, not part of the systematic data collection program and are pulished as miscellaneous measurements.
Water-resources data for the 1991 water year for Minnesota consist of records of stage, discharge and water quality of streams; stage, contents, and water quality of lakes and reservoirs; and water levels and water quality in wells and springs. The volume contains discharge records for 60 gaging stations; stage and contents for 9 lakes and reservoirs; water quality for 18 stream stations, 1 lake station, 22 partial-record sites, 1 precipitation station, 108 wells; and water levels for 119 observation wells. Also included are 59 high-flow partial-record stations. Additional water data were collected at various sites, not part of the systematic data collection program and are published as miscellaneous measurements or low-flow investigations.
In the National Water Plan it is described which measures must be taken to keep the Netherlands safe and livable for future generations and to make use of the chances offered by water.
swimmers in or around the water. Designate a responsible adult who can swim and knows CPR to watch swimmers in or around water. The supervisor should not be involved in any...
In the present thesis, the shell structure in exotic nuclei has been investigated. The focus of the work was on finding new experimental data in neutron-rich Cr and proton-rich Ca isotopes. The investigation of light Ca isotopes concentrated on the nucleus {sup 36}Ca which was produced in a knockout reaction from a radioactive {sup 37}Ca beam. For {sup 36}Ca, the excitation energy of the first 2{sup +} state has been measured for the first time. Furthermore, momentum distributions were analyzed using a Monte-Carlo simulation of the knockout reaction. This analysis yielded the contributions of neutrons from individual orbitals to the total knockout cross section. In principle, these may be used to calculate spectroscopic factors, but such a calculation is hampered by difficulties of present knockout-reaction models in predicting precise single-particle cross sections. The measured branching ratio to the ground and excited states, on the other hand, is close to the predicted value. A ...
Two-stage gasification allows power production from biomass and waste with high efficiency. The process involves pyrolysis at about 550C followed by heating of the pyrolysis gas to about 1300C in order to crack hydrocarbons and obtain syngas, a mixture of H2, CO, H2O and CO2. The second stage produces soot as unwanted by-product. Experimental results are reported on the suppression of soot formation in the second stage for two different fuels: beech wood pellets and Rofire pellets, made from rejects of paper recycling. Syngas obtained from these two fuels and from an industrial waste fuel has been cleaned and fed to a commercial SOFC stack for 250 hours in total. The SOFC stack showed comparable performance on real and synthetic syngas and no signs of accelerated degradation in performance over these tests. The experimental results have been used for the design and analysis of a future 25 MWth demonstration plant. As an alternative, a 2.6 MWth system was considered ...
An improved process is disclosed for reducing the water content of coal containing bound water by releasing at least a portion of the bound water by maintaining the coal at a temperature from about 220/sup 0/ to about 500/sup 0/ F. in the presence of water at a pressure sufficient to maintain at least portion of the water in a liquid phase for a time sufficient to release at least a portion of the bound water wherein the improvement comprises contacting the coal during such treatment with an active material selected from the group consisting of carboxylic organic acids containing up to about 6 carbon atoms, phenol, phenolic acids and inorganic acids.
In the United States, economic growth increasingly requires that greater volumes of freshwater be made available for new users, yet supplies of freshwater are already allocated to existing users. Currently, water for new users is made available through re-allocation of xisting water supplies-for example, by cities purchasing agricultural water rights. Water may also be made available through conservation efforts and, in some locales, through the development of ''new'' water from non-traditional sources such as the oceans, deep aquifer rackish groundwater, and water reuse.
Jet Propulsion Laboratory. California Institute of Technology. Pasadena, California. Energy and Water Conservation. Steve Rigdon. Facilities Energy Manager ...
The water and steam circuits of steam generators in pressurized-water nuclear power plants are described together with the mechanism of denting, and the corrosion of spacer plates that leads to cracks in tubes by constriction. The different chemical specifications applicable to the water of the secondary circuit of the generators in normal operation and on first commissioning are listed. The results obtained and the measurements of chemical values taken in operation on the water in the secondary circuits of steam generators at Fessenheim and Bugey are presented.
The water and steam circuits of steam generators in pressurized-water nuclear power plants are described together with the mechanism of denting, and the corrosion of spacer plates that leads to cracks in tubes by constriction. The different chemical specifications applicable to the water of the secondary circuit of the generators in normal operation and on first commissioning are listed. The results obtained and the measurements of chemical values taken in operation on the water in the secondary circuits of steam generators at Fessenheim and Bugey are presented.
Cooling water is sprayed on the outer surface of an upper portion of a container, and a pool is formed by the cooling water flowing down while cooling the container. Further, the cooling water stored in the cooling water pool is recycled by a pump for spraying the cooling water on the outer surface of the upper portion of the container. Sufficient amount of cooling water is supplied for spraying the cooling water to the outer surface of the upper portion of the container so that the outer surface of the container is free from drying and a liquid membrane is formed on the entire surface. The amount of the cooling water is made greater than that of the cooling water evaporated when the entire amount of the heat generate in the reactor core of the reactor is transferred to the cooling ...
Abstract Salmonella Typhimurium and Listeria monocytogenes are major bacterial pathogens associated with poultry products. A controlled released ClO2 sachet applied with modified atmosphere packaging (MAP) was evaluated for its ability to control the growth of S. Typhimurium and L. monocytogenes on raw chicken breast during refrigerated storage. The fresh chicken samples were inoculated with one or the other of the pathogens at 104-cfu/g, and the packages (with and without ClO2 sachet) were flushed with ambient air or 30% CO2/70% N2 before sealing, and then stored at 4C for up to 21 days. The maximum reduction in MAP plus ClO2 (compared with MAP alone) was 0.68-log-cfu/g for S. Typhimurium and 1.87-log-cfu/g for L. monocytogenes. Color and pH changes of the chicken breast were observed at ...
High concentrations of toxic chemicals in sediment and white croaker (Genyonemus lineatus), as well as liver diseases (e.g., carcinomas) in this species, were found in the Los Angeles area. The highest concentrations of aromatic hydrocarbons (AHs) in the sediment were in San Pedro Bay, and the highest concentrations of 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) derivatives were in sediment from near the White Point sewer outfall. Concentrations of AHs, polychlorobiphenyls (PCBs), and DDT derivatives were generally higher in food organisms from the croaker's stomach than in sediment. Moreover, croaker from San Pedro Bay and White Point were substantially contaminated with DDT derivatives and metabolites of aromatic compounds, compared to croaker from the Hyperion outfall and Dana Point. The evidence suggest that the observed pathological conditions of the liver were associated with exposure of the croaker to toxic chemicals, which occurred, at least in part, through ...
Nitromethane (CH(3)NO(2)) and its chlorinated analogue, chloropicrin (CCl(3)NO(2)), were photolyzed at 193, 248, and 266 nm, and the products were observed by time-dependent Fourier transform infrared emission spectroscopy. At 193 and 248 nm, the primary photodissociation pathway for nitromethane was cleavage of the C-N bond to produce CH(3) + NO(2)(A (2)B(2)). At 266 nm, weak emission was observed following photodissociation of nitromethane, but an infrared spectrum could not be obtained. The photodissociation of chloropicrin at 193 nm produced the analogous product channel CCl(3) + NO(2)(A (2)B(2)) in addition to several other product channels. At 248 and 266 nm, only CCl(3) + NO(2)(A (2)B(2)) was observed. The production of phosgene (CCl(2)O) from chloropicrin photodissociation was not observed in this study. PMID:16571044
SiO/sub 2//Si samples prepared in 2% and 4% HCl/O/sub 2/ mixtures at 1200/sup 0/C have been annealed in H/sub 2/O/N/sub 2/ ambients at 1200/sup 0/C. The anneals ranged up to 16 hrs in ambients with 4 or 40 ppM H/sub 2/O in N/sub 2/. Rutherford backscattering measurements have been made to determine the amount and location of Cl incorporated in these samples. A linear loss of Cl with annealing time is found for all samples. Changes in the distribution of Cl near the SiO/sub 2//Si interface are found. These changes are interpreted in terms of morphological changes in the third (Cl containing) phase. A significant effect of the H/sub 2/O content of the N/sub 2/ ambient is observed.
The association of Finnish Plastics Industry examined the possibilities to utilize energy content of plastic wastes in spring 1990. A bark fuelled boiler plant of forest industry was used as test power plant. The power of the plant was 60 Mw. This report discusses shortly the theory of combustion of plastics. About 130 000-15 000 tons of plastic waste, corresponding to 7 % of the solid municipal waste, is dumped annually in Finland. Utilization of the plastic waste recovered from municipal wastes for energy production is technically viable in present power plants among present energy production. The chipping and mixing of the plastic in the other fuel are the only pretreatment required for the plastic waste. In Finland there are several power plants using suitable fuels for plastic mixture combustion. The portion of the plastic of the total fuel power was 10 %. No problems occurred during the tests. The results of the tests are presented in this report. Special attention has been paid ...
Pitting corrosion of Inconel 600 was examined in chloride and sulfate solutions through usage of potentiodynamic polarization techniques. The effects of chloride and sulfate concentration were investigated in the range of 0.0001 to 0.1 M. Increasing chloride concentrations resulted in active shifts of the pit nucleation potential. Immunity to pitting corrosion was evident at a chloride level below 0.005 M. Increasing sulfate concentrations resulted in improved pitting resistance of Inconel 600 in chloride solutions. Detrimental effects associated with pitting were evident with low-level sulfate being added to dilute chloride media. The density of pits increased with increasing chloride concentrations or temperature between room temperature and 70 C. Systematic trends for the depth of pits were not evident. The observations of pitting corrosion in open immersion were consistent with those in polarization methods. Corrosion products contained in the pits were enriched in nickel, chromium ...
The antimicrobial effects and quality changes of O2, He, N2 or N2O-enriched active modified atmosphere packaging -MAP- (100 kPa initial gas partial pressure) compared to a chlorinated -100 mg L-1 NaClO- passive MAP (control) in fresh-cut Red Chard baby leaves up to 8 days at 5 degreeC were studied. High O2 MAP (>85 kPa O2) inhibited natural microflora growth during 7 days at 5 degreeC. Regarding control treatment, no differences for He and N2O-enriched MAPs on microbial growth were found although control samples were previously disinfected. Initial total phenolics content (613 mg ChAE kg-1 fw) increased up to 61-93% after 6 days at 5 degreeC under O2, He, and N2-enriched MAPs. Vitamin C content decreased up to 67% after shelf life in control samples while lower decreases were monitored in ...
Chlorinated organics are frequently found as harmful soil contaminants and persisted for extended periods of time. A novel approach, named pulsed corona discharge plasma (PCDP), was employed for the degradation of pentachlorophenol (PCP) in soil. Experimental results showed that 87% of PCP could be smoothly removed in 60 min. Increasing pulse voltage, enhancing soil pH, lowering humic acid (HA) in soil and reducing granular size of the soil were found to be favorable for PCP degradation efficiency. Oxidation and physical processes simultaneously contributed to PCP removal in soil and ozone was the main factor in PCDP treatment. C-Cl bonds in PCP were cleaved during PCDP treatment by Fourier transform infrared spectroscopy (FTIR) analysis. The mineralization of PCP was confirmed by total organic carbon (TOC) and dechlorination analyses. The main intermediate products such as tetrachlorocatechol, tetrachlorohydroquinone, acetic acid, formic acid, and oxalic acid were ...
Field corrosion tests were conducted on eight single tube materials and two welded overlay materials in three typical Japanese waste incineration plants in an effort to develop new corrosion-resistant superheater tubes capable of functioning efficiently under temperature and pressure conditions of 500 C and 100 kgf/cm{sup 2}-g in high-efficiency waste-to-energy (WTE) plants. Austenitic alloys containing higher concentrations of chromium, nickel, and molybdenum [Cr + Ni + Mo] showed excellent corrosion-resistant properties, and the new alloys JHN24 and HR30M showed good corrosion resistance. Different corrosion rates found in each of the three plants were explained by differences in operating conditions, such as gas temperature, concentration of molten salts resulting from chlorine (Cl) content of deposits, heavy metal (zinc oxide [ZnO] + lead oxide [PbO]) content, etc. It was confirmed that the corrosion rate of materials positioned in the first tube row facing the ...
The partitioning of transuranium elements (TRUs) from high-level liquid waste (HLLW) through the use of pyrometallurgical technology has been underway since 1986, for the purpose of the improving the safety and public acceptance of the disposal of high-level vitrified waste. Prior to the pyrometallurgical partitioning process, the alkali metals can be separated at the denitration process for oxide conversion of HLLW, chlorination in a chloride salt bath can be used to effectively convert oxides to chlorides, and evaporated chlorides can be captured with high efficiency in another adopted chloride salt bath. The higher separation factors between actinides and rare earths are obtained in a LiCl-KCl/Bi system than in a LiCl-KCl/Cd system. Based on the results, we propose a practical process flow for partitioning TRUs from HLLW by pyrometallurgical technology. This process was demonstrated successfully using simulated purex waste. Each element of the TRUs was separated ...
Water-resources data for the 1993 water year for Texas are presented in four volumes, and consist of records of stage, discharge, and water quality of streams and canals; and stage, contents, and water quality of lakes and reservoirs; and water levels and water quality of ground-water wells. Volume 3 contains records for water discharge at 134 gaging stations; stage only at 1 gaging stations; stage and contents at 13 lakes and reservoirs; water quality at 81 gaging stations; and data for 30 partial-record and 4 flood-hydrograph partial-record stations. Also included are lists of discontinued surface-water discharge or stage-only stations and discontinued surface-water-quality stations; crest-stage and flood-hydrograph partial-record stations, reconnaissance ...
The chemistries of reactants, plasticizers, solvents and additives in an epoxy paint are discussed. Polyamide additives may play an important role in the absorption of molecular iodine by epoxy paints. It is recommended that the unsaturation of the polyamide additive in the epoxy cure be determined. Experimental studies of water absorption by epoxy resins are discussed. These studies show that absorption can disrupt hydrogen bonds among segments of the polymers and cause swelling of the polymer. The water absorption increases the diffusion coefficient of water within the polymer. Permanent damage to the polymer can result if water causes hydrolysis of ether linkages. Water desorption studies are recommended to ascertain how water absorption affects epoxy paint.
...Species - see CITES Trade of Dangerous Chemicals Transport and Environment U Urban Environment Use of natural resources V Volatile Organic Compounds W Waste Landfills Waste electrical and electronic equipment - see WEEE Waste incineration Waste legislation - reporting Waste management planning Waste oils Waste shipments Waste water - see Urban waste waterWater Bathing Water Drinking water Floods Marine environment Urban waste waterWater Framework Directive WEEE - Waste Electric and Electronic Equipment Wildlife ...
This report is a summary of the contribution of nitrogen and phosphorus in the eutrophication process of inland and coastal waters. Special attention was paid to the mechanisms of these nutrients in regulating biological processes and to the methods available in estimating their effects in the eutrophication of water bodies. The report includes five chapters which are entitled: Introduction, which is a general background to the subject with special attention to the requirements of the Finnish Water Act. Phosphorus and nitrogen as factors regulating biological processes. The topics included are: definition of eutrophication, forms of phosphorus and nitrogen and their sources to inland and coastal waters, effects of these nutrients as growth factors of phytoplankton and macrophytes and consequences of eutrophication. Estimation of the effects of phosphorus and nitrogen. The topics discussed from the point ...
This procedure describes the formulation and make-up of Simulated Dilute Water (SOW), a low-ionic-content water to be used for Activity E-20-50, Long-Term Corrosion Studies. This water has an ionic content which is nominally a factor of ten higher than that of representative waters at or near Yucca Mountain. Representative waters were chosen as J-13 well water [Harrar, 1990] and perched water at Yucca Mountain [Glassley, 1996]. J-13 well water is obtained from ground water that is in contact with the Topopah Spring tuff, which is the repository horizon rock. The perched water is located in the Topopah Spring tuff, but below the repository horizon and above the water table. A nominal times ten higher ionic content was chosen to simulate the effect of ionic ...
The study investigates the possibility of enhancing crop water productivity in the parts of Northwest India where groundwater quality is marginal and canal water supply is severely scarce. Soil, Water, Atmosphere and Plant (SWAP) model was calibrated and validated in three farmers' fields with varying canal water availability and groundwater quality in the Kaithal Irrigation Circle of the Bhakra Canal system, Haryana. On the basis of predicted and observed soil water content, pressure heads, salt concentration at 2 week intervals and crop yields, the model was found suitable for use in the region. A few nomographs were prepared to provide a graphical method to predict the effect of different combinations of water quality and depth of water application on crop yield and soil salinity and to...
The research committee of the Atomic Energy Society of Japan on water chemistry standard aims at establishing the private standard of water chemistry of nuclear power plants. The committee gathers up 'BWR water chemistry management manual', 'PWR primary system water chemistry management manual' and 'PWR water chemical analysis standard method', and furthermore aims at the standardization of those in future. Looking back on the committee's activities for the past four years, latest results of research of water chemistry mainly contributing to safe and reliable nuclear power plants were described with the future perspective of water chemistry and a demanded break-through. (T.T.)
Using the Laser-Fluorescence technique, an investigation was made, adopting the standard mix method, on trace uranium concentrations in hot spring water and geothermal water from Lishan region, and in tap water from some major cities in Shanxi province. Totally 40 samples from 27 sites were investigated. Measurement showed that the tap water contains around 10"-"6 g/L of uranium, whose concentrations in both hot spring water and geothermal water are 10"-"5 g/L. Most of samples are at normal radioactive background level, some higher contents were determined in a few samples
...AquaMagna Water Conditioner and Descaler OCETA Environmental Technology & Business Profiles AQUAMAGNA WATER CONDITIONER AND DESCALER CAT. #03-018 CONTACT: Magna-Tek ...removal high-strength ceramic magnet no energy input The AquaMagna Water Conditioner and Descaler is a non-chemical method of water treatment. The technology uses ... Figure 1: The AquaMagna Water Conditioner and Descaler PROCESS/ PRODUCT APPLICATION: hard water domestic water process water reverse osmosis heat exchangers cooling ... For once-through or recirculating heating or cooling equipment, the AquaMagna descaler improves thermal efficiencies and reduces downtime. Figure 2 illustrates a cross-section ...
This paper presents a novel domestic hot water heater model to be used in a multi-objective demand side management program. The model incorporates both the thermal losses and the water usage to determine the temperature of the water in the tank. Water heater loads are extracted from household load data and then used to determine the household water usage patterns. The benefits of the model are: (1) the on/off state of the water heater and temperature of the water in the tank can be accurately predicted, and (2) it enables the development of water usage profiles so that users can be classified based on usage behaviour. As a result, the amount of ancillary services and peak shaving that can be achieved are accurately predictable and can be maximized without adversely affecting users. (author)
...Tota-MaharajE-Mail: Interests: water and wastewater treatment, environmental engineering and sustainable systems; sustainable water management; sustainable urban drainage systems (SUDS); combined renewable energy applications with reverse osmosis desalination; microbial fuel cells for bioenergy production and treatment of urban wastewater; solar photocatalytic treatment and disinfection of water/wastewater Dr. Simon Toze CSIRO Land and Water, Queensland Bioscience Precinct - St Lucia, 306 Carmody Road, St Lucia QLD 4067,...
Indicators of source water use in different economic branches, water consumption in recycling and recycling-successive water supply in 1980?2006 are analyzed. Trends were identified in variations in specific water consumption in industry, agriculture, and municipal economy. Territorial differentiation of wetness indicators of regional product over federal districts and constituent territories of the RF is shown. Wetness values of gross domestic product in different economies are compared.
number Fax (501) 228-3600 (501) 228-3601 Surface Water Data Information Requests Bill Baldwin (501) 228-3602 Surface Water General Information Jaysson Funkhouser (501) 228-3663...
Background Microbial water-quality indicators, in high concentrations in sewage, are used to determine whether water is safe for recreational purposes. Recently, the use of these indicators...Full Text Available
In order to reduce the air concentration of (sup 3)H in the reactor buiIding of Wolsung Heavy Water Reactor, a computer code for estimation of adsorption behavior was programmed based on an equation derived for analysis of water vapor adsorption, and a ba...
Before the implementation Water Framework directive, it was usual to forget that a good environment protection of the receiving waters needs a correct and coordinated operation of the subsystems of the water cycle, specially sewerage system, WWTP and receiving waters. This explains that most of the countries have focused their efforts in the treatment of dry weather flows forgetting the management of wet weather flows. Actually the idea that a sewerage system or a WWTP can not be planned or managed independently without considering the effects on the receiving waters is commonly accepted because not only each one of these systems must work correctly but also it is required a minimum impact in the receiving waters of the sewerage and WWTP overflows in dry and wet weather. All these links will affect the management strategy of the sewerage system (storm ...
The effect of the water-chemical regime (WCR) on damage sustained by heating surfaces of steam generators at NPP is analyzed. It is indicated that phosphate treatment with minimal excesses of phosphates in the steamgenerator water is the most optimal method of managing the WCR regime of horizontal steam generators.
The effect of water stress on patterns of nitrate reductase activity in the leaves and nodules and on nitrogen fixation were investigated in Medicago sativa L. plants watered 1 week...Full Text Available
The reference medium for brachytherapy dose measurements is water. Accuracy of dose measurements of brachytherapy sources is critically dependent on precise measurement of the source–detector...Full Text Available
A model was developed to compute concentration of impurities in the WWER 440 steam generator (SG) secondary water along the tube bundle. Calculated values were verified by concentration values obtained from secondary water sample chemical analysis. (orig.). 2 refs.
A method of measuring the water potential of stored potato tubers (Solanum tuberosum L.) was needed to investigate the relationship of bacterial soft rot in tubers to water potential....Full Text Available
By the time of primary 21st century, water hyacinth had become a serious environmental problem in China. Water hyacinth contributes to the major part of ecological hazards from the invasion of foreign...Full Text Available
Background and AimsXylem vessels containing gases (embolized) must be refilled with water if they are to resume transport of water through the plant, so refilling is of great importance...Full Text Available
average bulk water temper ature rise, OF bulk water temperature at elevation z, OF bulk water temperature in channels 0 and 1, O F film temperature, OF ...
Object: To smoothly control automatic water supply for realizing stable operation of a nuclear reactor by providing a flow rate limiting signal selection circuit and a preferential circuit in a water supply control device for a nuclear reactor wherein the speed of a recirculation pump may be changed in two-steps. Structure: Opening angle signals for a water supply regulating valve are controlled by a nuclear reactor water level signal, a vapor flow rate signal and a supplied water flow rate signal through an adder and an adjuster in response to a predetermined water level setting signal. When the water in the reactor is maintained at a predetermined level, a selection circuit receives a water pump condition signal for selecting one of the signals from a supplied water rate limiting signal generator ...
Inadequate measures of water quality have been used in many studies of the health effects associated with water supplies in developing countries. The present 1-year epidemiological-microbiological study...Full Text Available
In a supercritical water-cooled reactor, property of water changes significantly around the critical point. It is expected that irradiation and change of water property will affect the chemistry and material corrosion. Deep understanding of interactions between supercritical water and materials under irradiation is important. However, comprehensive data on radiolysis, kinetics, corrosion and thermodynamics have not been obtained due to the severe experimental condition. To get such data by experiments and computer simulations, a national program funded by Ministry of Education, Culture, Sports, Science and Technology (MEXT) has been started since December 2002. (author)
In this paper the diffusion of tritiated water vapor into concrete walls is studied to evaluate tritiated water retention capacity of a fusion reactor concrete building. Using a model of the tritiated water diffusion determined form experimental results, depth profiles of tritiated water in concrete are calculated in the case of being exposed to air containing tritiated water vapor during the normal operational condition of a fusion reactor. A 0.5-m-thick concrete is sufficient for reactor hall walls from a viewpoint of the tritium containment.
In this paper the diffusion of tritiated water vapor into concrete walls is studied to evaluate tritiated water retention capacity of a fusion reactor concrete building. Using a model of the tritiated water diffusion determined form experimental results, depth profiles of tritiated water in concrete are calculated in the case of being exposed to air containing tritiated water vapor during the normal operational condition of a fusion reactor. A 0.5-m-thick concrete is sufficient for reactor hall walls from a viewpoint of the tritium containment.
The transport of liquid water and gaseous reactants through a gas diffusion layer (GDL) is one of the most important water management issues in a proton exchange membrane fuel cell (PEMFC). In this work, the liquid water breakthrough dynamics, characterized by the capillary pressure and water saturation, across GDLs with and without a microporous layer (MPL) are studied in an ex-situ setup which closely simulates a real fuel cell configuration and operating conditions. The results reveal that recurrent breakthroughs are observed for all of the GDL samples tested, indicating the presence of an intermittent water drainage mechanism in the GDL. This is accounted for by the breakdown and redevelopment of the continuous water paths during water drainage as demonstrated by Haines jumps. For GDL ...
Water is one of our most precious resources. However, for many in the United States, having fresh, safe drinking water is taken for granted, and due to this perceived lack of relevance, students may not fully appreciate the luxury of having safe running water--in the home. One approach to resolving water-quality issues in the United States may reside in providing education that presents accurate information in a meaningful way. Accordingly, this article describes a unit designed to emphasize the importance of water-quality testing and purification and to introduce students to local water-quality issues. The engineering-based module of this eighth-grade science activity is particularly important due to the design-build-test component. (Contains 5 figures.)
Most plans for the disposition of surplus nuclear materials involve storage in sealed containers where the evolution of gases from reactions of adsorbed water could present both pressure and flammability hazards[l] . Despite efforts such as calcining the material to minimize the water content prior to packaging, both residual moisture and readsorbed water may be present in the final containers . Given the anticipated temperature excursions during transportation and storage, this water may thermally desorb, increasing the pressure, and/or thermally dissociate to produce H2 gas, increasing flammability hazards . In addition, the radiation from the nuclear material may induce radiolysis of the water with the likely products being water vapor, H2, 02 and H2O2. In order to better understand the relative importance of the thermal- and radiationinduced chemistry, we ...
Ground water is treated in the Czech Republic so that small water tanks are built above each water source to serve the primary ground water treatment; water so pretreated is then concentrated in large basins for subsequent treatment. Some water tanks where the first contact of the ground water with air takes place were selected as sites predisposed to radon accumulation. The examination was carried out near the town of Jihlava, where the bedrock contains slightly elevated radium concentrations. The average radon concentrations lay within the region of 2-4 kBq/m"3; the instantaneous values, however, exhibited appreciable periodical variations during the day. The relatively high radon concentrations will not pose a marked hazard for the personnel because the employees only reside at the sites in question for 10 to 15 minutes within 2 days, not ...
A single cylinder diesel engine study of water-in-diesel emulsions was conducted to investigate the effect of water emulsification on the engine performance and gases exhaust temperature. Emulsified Diesel fuels of 0, 5, 10, 15 and 20 water/diesel ratios by volume were used in a single cylinder, direct injection diesel engine, operating at 1200-3300 rpm. The results indicate that the addition of water in the form of emulsion improves combustion efficiency. The engine torque, power and brake thermal efficiency increase as the water percentage in the emulsion increases. The average increase in the brake thermal efficiency for 20% water emulsion is approximately 3.5% over the use of diesel for the engine speed range studied. The proper brake specific fuel consumption and gases exhaust temperature decrease as the percentage of water in the ...
... Marine transport and oil disposal by boats and Matadi pose threats in the region. When the water ... Marine transport and oil disposal by boats and Matadi pose threats in the region. When the water ... ...
This site explains how temperature, pressure, and salinity work together to determine the density of ocean water. The three density layers of the ocean are described by means of text description and a graphic illustration.
Using air as a carrier gas is common in humidification?dehumidification desalination processes. A computer program was written using mass and energy balances for modeling the process behavior. The parameters considered in this work were inlet air and fresh water recycle temperatures, inlet air flow rate, saline water and fresh water recycle flow rates, and saline water to air flow ratio. Results of simulation showed that increasing inlet air and fresh water recycle flow rate increases fresh water production. It was also found that heating the inlet air to humidification column or cooling the inlet water to dehumidification column increases the production rate but increasing water to air flow ratio in a humidifier leads to a lower production rate. The predicted effects of the parameters on ...
The largest outbreak of cryptosporidiosis reported in the United Kingdom, involving 575 confirmed cases (of which 474 met an agreed case definition), occurred in the county of Devon during August and September of 1995. The descriptive epidemiology supports the hypothesis that the outbreak was associated with the consumption of cold tap water in the area served by a particular water treatment works. Cryptosporidium oocysts were detected in treated water samples at the time of the outbreak. Although the epidemiological analysis provided strong circumstantial evidence of a waterborne outbreak, the data were not recorded in a manner that made them admissible in criminal proceedings taken by the Drinking Water Inspectorate against the water company involved. The need to carry out an analytical study in conjunction with the identification and characterisation of the pathogen in the ...
metric temperatures has been prepared showing the surface water temper- ... occasion, gray levels show different densities for similar water temper- ...
... should give full con- As for the effects of the Three Gorges on the mouth of sideration to the rising water process and water temper- the river, the ...
ObjectiveTo evaluate the effect of moderate aerobic physical activity in water on fetal cardiotocography patterns in sedentary pregnant women.MethodIn...Full Text Available
The very low-pressure expansion tank of the title invention is connected to the water in the central heating installation via a connecting pipe with a pump and valves on one side, and on the other side the tank is connected via a connecting pipe with valve to the tap water mains, so that the supply of water can be regulated automatically. Within the expansion tank contact with the outside air is not possible because of an air/water separating floater. By means of recording and control (also remote) of the contents of the expansion tank, the installation pressure and the quantity of supplied water from the expansion tank and the tap water mains, failures and water damage are prevented. 4 figs.
An environmental study was done to examine the prevalence of Vibrio mimicus in some aquatic environments of Dhaka, Bangladesh, and of Okayama, Japan. Water samples from Dhaka environments and water...Full Text Available
density is slightly higher, its electrical conductivity is much higher, and it is slightly ... Sea water has characteristic properties (e.g. density) that are independent of ...
In the Mediterranean arc, vines for wine production are mainly grown without the support of irrigation. Under such conditions, site variables affecting the extent and seasonal timing of water deficits are the dominant environmental constraints for grape production. Moreover, water availability and vine water status are the factors most comprehensively determining fruit composition and, thus, wine quality. Therefore, monitoring the extent of water stress in vines might be a valuable tool for the optimisation of grape yield and quality. The objective of this study was to evaluate the feasibility of using the reflectance based Water Index (WI) to estimate vine water status at the leaf and canopy levels. The study was conducted on Vitis vinifera cv. Chardonnay potted plants submitted to contra...
Halothane, chloroform, and carbon tetrachloride, in the vapor and liquid phases, stimulate the water receptor of the blowfly Phormia regina. There are three successive phases of response to long-lasting...Full Text Available
In this paper, we calculated the radioactive concentration distribution of radioactive waste water, the temperature distribution of drained cooling water and the effect of implement from the Daya Bay Nuclear Power Plant on nearby waters range, discussed and analysed some problems of computational results and computation with Alternating Direction Implicit Method (ADI). The contents of the article included: the establishment of two-dimension tidal current equation, radioactive waste water pollutant dispersion equation and cooling water heat convection diffusion equation, the numerical difference calculation model of tidal current field, concentration field as well as temperature field, effect impingement with ADI method, numerical calculation results. The result of research showed that: when the Daya Bay Nuclear Power Plant is on normal operation and after the low level radioactive ...
This paper, firstly, introduces the background in developing a high quality water supply system, in which the drinking water system is isolated inside a building. Results of questionnaire on the high quality service water are illustrated. The results of questionnaire have revealed that the high quality service water is extremely interested. Then, are described the target quality of high quality water, the constitution of high quality water supply system, the treatment process, the measures to secure safety and sanitary, and the method of maintenance. The high quality water is produced through the activated charcoal absorption treatment, membrane treatment, ozonation, cooling, mineral addition, and disinfection of city water. Furthermore, application examples of this system adopted to a department store and a bachelor ...
In an attempt to obtain basic data for evaluation of exposure doses in Niigata Prefecture, the concentrations of tritium in atmospheric water, precipitation, river water, and tap water were measured. Samples of atmospheric water, river water, and tap water were collected once for 2 weeks; and precipitation collected for one week was used as sample. The concentration of atmospheric tritium depended on the concentration of tritium in moisture and the content of water in atmosphere. Tritium levels were high in May, November and March, and low in September. Regarding tritium concentrations, there was a good correlation between atmospheric water and precipitation. Tritium concentrations in both of them varied from sample to sample. The concentrations of tritium in river and tap water tended to be high ...
In Pakistan, the agricultural sector is the largest water user with 95%, leaving only marginal quantities for households and industry. On one hand, agriculture is a very important sector in Pakistan's economic development, contributing about 23 % to the national GDP -but industry contributes slightly more using only about 2 % of the available water resources. As Pakistan faces a growing problem of water shortage, significant achievements in water conservation have to be materialized, predominantly on the agricultural sector. There is scope for a higher degree of efficiency in water use, as water losses, namely in irrigation, are still rather high. There is another good reason for water conservation in agriculture: Over-irrigation results in rising water tables and increased soil salinity, which has reduced Pakistan's ...
This document summarizes the degree to which State water quality standards include wetlands in their definitions of State waters. The detailed review of other elements of standards, such as uses, criteria and antidegradation, is beyond the scope of this review. The purpose of this review is to provide a baseline of information for the development of EPA guidance and policies related to water quality standards for wetlands.
In this paper the possibility of configuring a water cooled Nuclear Thermal Propulsion (NTP) rocket, based on a Particle Bed Reactor (PBR) is investigated. This rocket will be used to operate on water obtained from near earth objects. The conclusions reached in this paper indicate that it is possible to configure a PBR based NTP rocket to operate on water and meet the mission requirements envisioned for it. No insurmountable technology issues have been identified.
...In 2000, the Water Framework Directive (WFD) came into force, introducing a comprehensive, river basin based water management for Europe. The aim of the Directive is ...In 2000, the Water Framework Directive (WFD) came into force, introducing a comprehensive, river basin based water management for Europe. The aim of the Directive ...
Water transport in the ionomeric membrane, typically Nafion{reg_sign}, has profound influence on the performance of the polymer electrolyte fuel cell, in terms of internal resistance and overall water balance. In this work, high resolution neutron imaging of the Nafion{reg_sign} membrane is presented in order to measure water content and through-plane gradients in situ under disparate temperature and humidification conditions.
General corrosion behavior of ALLOY 800 in high temperature water was studied in relation to its surface film structure. The surface film formed in water was found to decrease the corrosion rate of ALLOY 800. This film is composed of Ni ferrite, and can be obtained by oxidation in air or steam. Based on these results, air or steam oxidation treatment to inhibit Ni and Co release of ALLOY 800 into high temperature water is proposed. (author).
General corrosion behavior of ALLOY 800 in high temperature water was studied in relation to its surface film structure. The surface film formed in water was found to decrease the corrosion rate of ALLOY 800. This film is composed of Ni ferrite, and can be obtained by oxidation in air or steam. Based on these results, air or steam oxidation treatment to inhibit Ni and Co release of ALLOY 800 into high temperature water is proposed. (author).
The soil water characteristic curve, h(theta), can be used to estimate a variety of parameters in unsaturated soils. One practical application of h(theta) is its use by DRAINMOD, a drainage model that has been widely used in shallow water table regions, to determine the water table depth¿drainage v...
This book contains the Proceedings of the Conference on Climate and Water under the following groupings: Impacts of climatic variability and change-resulting from the changes in hydrological variables; Aquatic environment; Terrestrial environment; Coastal zones and navigation; Urban and industrial water supply and drainage; Energy production; Intropogenic changes of climate and water management problems; Flood potential; Irrigation and land drainage.
This book contains the Proceedings of the Conference on Climate and Water under the following groupings: Impacts of climatic variability and change-resulting from the changes in hydrological variables; Aquatic environment; Terrestrial environment; Coastal zones and navigation; Urban and industrial water supply and drainage; Energy production; Intropogenic changes of climate and water management problems; Flood potential; Irrigation and land drainage.
After the devastating natural disasters that have hit China recently, another crisis is looming, Drought, pollution and heavy usage in the fast-developing megacities have resulted in a shortage of water. A huge construction effort is underway to divert water from the south to the north. But experts warn that it will not solve China's structural water problems.
... Hale, Markku Kulmala, 373.43 EUR; 225.00 USD; 276.00 GBP... Aerosol Chemical Processes in the Environment Spurny, Kvetoslav R., $164,95, 䀈... More Journals » MAGAZINES & JOURNALS Water Science & Technology: Water Supply Water Science and Technology: Water Supply is p... ...
...2010-10-01 false Electric hot water supply boilers. 63.25-3 Section 63.25-3...Boilers § 63.25-3 Electric hot water supply boilers. (a) Electric hot water supply boilers that have a capacity not...
Singlet oxygen generators are multiphase flow chemical reactors used to generate energetic oxygen to be used as a fuel for chemical oxygen iodine lasers. In this paper, a theoretical model of the generator is presented along with its solutions over ranges of parameter space and oxygen maximizing optimizations. The singlet oxygen generator (SOG) is a low-pressure, multiphase flow chemical reactor that is used to produce molecular oxygen in an electronically excited state, i.e. singlet delta oxygen. The primary product of the reactor, the energetic oxygen, is used in a stage immediately succeeding the SOG to dissociate and energize iodine. The gas mixture including the iodine is accelerated to a supersonic speed and lased. Thus the SOG is the fuel generator for the chemical oxygen iodine laser (COIL). The COIL has important application for both military purposes--it was developed by the US Air Force in the 1970s--and, as the infrared beam is readily absorbed by metals, industrial cutting ...
The environments on the drip shield and waste package outer barrier are controlled by the compositions of the waters that contact these components. the temperature (T) of these components, and the effective relative humidity (RH) at these components. Because the composition of the waters that are expected to enter the emplacement drifts (either by seepage flow or by episodic flow) have not been specified: well J13 water was chosen as the reference water (Harrar 1990). Section 6.2 discusses the accessible RH for the temperatures of interest at the repository horizon. Section 6.3 discusses the adsorption of water on metal alloys in the absence of hygroscopic salts. Because the temperatures of the DSs and the WPOBs are higher than those of the surrounding near-field environment, the relative humidity at the DSs and the WPOBs will be lower than that of the surrounding near-field ...
A solar energy desalination process utilizing solar radiation directly for the evaporation of salt water is described. Ambient air takes on water vapor as the air passes through an evaporative medium. It is then directed between a saline water-covered, solar absorbing surface and a solar collecting housing. The resulting heated and moisture-saturated air is cooled in a heat exchange means where condensation of fresh water occurs. Simultaneously, cool salt water is utilized as the cooling water in the heat exchange means, and takes on the heat of condensation given up by the condensing vapor. The heated salt water from the heat exchange means is partially directed over the solar absorbing surface, and at least a portion of it is also directed to wet the evaporative medium. Several optional sub-processes are described for operation of the ...
This study quantifies the external water footprint of the Netherlands by partner country and import product and assesses the impact of this footprint by contrasting the geographically-explicit water footprint with water scarcity in the different parts of the world. The total water footprint of the Netherlands is estimated to be about 2300 m^3/year/cap, of which 67% relates to the consumption of agricultural goods, 31% to the consumption of industrial goods, and 2% to domestic water use. The Dutch water footprint related to the consumption of agricultural goods, is composed as follows: 46% related to livestock products; 17% oil crops and oil from oil crops; 12% coffee, tea, cocoa and tobacco; 8% cereals and beer; 6% cotton products; 5% fruits; and 6% other agricultural products. About 11% o...
Water?rock interaction is one of the prime factors affecting the fluoride contents of surface and groundwater. If fluoride concentration of drinking water has been neglected, excess fluoride can cause serious dental and medical problems on human health, which is well known at Golcuk-Isparta region. In the research area, Egirdir lake, Golcuk lake and surrounding springs have been utilized as drinking water sources. Golcuk lake water and surrounding groundwaters have high fluoride content (1.4?4.6?mg/l), which is above the WHO standards. Fluoride is predominantly supplied by dissolution of fluoride within the fluormicas of volcanics during the circulation of water. Fluoride concentrations of waters have shown variations for dry and rainy seasons depending on the degree of interaction between...
We present an innovative approach to estimating residential irrigation water demand for a large metropolitan area using GIS data, weather station data, and a water budget modeling approach commonly used by plant scientists and landscape management professionals. An important question addressed by our study is how a growing urban forest affects the overall irrigation water demand of a semiarid metropolitan area. To estimate the amount of water required by residential landscaping, we consider water demand to be a function of the areal extent of residential landscaping (i.e. tree/shrub or turf grass), the water-loss rate for different landscaping types, the efficiency with which the landscape is irrigated, and local climatic factors (i.e. reference evapotranspiration and precipitation). We es...
Purpose: To stably control the reactor water level so as not to cause excess water feeding in a BWR type reactor. Constitution: A flow control valve is disposed to the exit of a feedwater pump for a nuclear reactor and the valve is controlled by a flow regulator to maintain the water level constant in the reactor. A signal from a water level controller is inputted to the flow regulator to thereby control the flow rate control valve. In this case, the flow regulator remains in a saturated state just after the starting of the feedwater pump, in which the pump flowrate is at 100% to result in an excess water feeding condition. In view of the above, a feedback circuit is provided to the flow regulator so that the saturated state is eliminated and the water feeding can be controlled directly from the water level controller. (Kamimura, M.).
Purpose: To remove excessive driving pressure applied to an unisolated control rod drive by returning excessive coolant to a condensed water storage tank or to the inlet side of a drive water pump using a coolant flow rate control pipe of a control rod driving hydraulic system. Constitution: Excessive water is returned to a condensed water tank while controlling the excessive coolant by a flow control valve in response to variations in the pressure difference between the reactor pressure and the driving water line when the control rods are isolated using a pipe from the outlet side of the drive water pump to the condensed water storage tank. Thus, the control rod to be isolated is prevented form being dropped. (Sekiya, K.).
This paper presents a study on Manasbal lake, which is one of the high altitude lakes in the Kashmir Valley, India. Eighteen water samples were analysed for major ions and trace elements to assess the variability of water quality of the lake for various purposes. Geostatistics, the theory of regionalized variables, was then used to enhance the dataset and estimate some missing spatial values. Results indicated that the concentration of major ions in the water samples in winter was higher than in summer. The scatter diagrams suggested the dominance of alkaline earths over the alkali elements. Three types of water were identified in the lake that are referred to as Ca?HCO3, Mg?HCO3 and hybrid types. The lake water was found to be controlled by rock?water interaction with carbonate lithology ...
Seven villages in southeastern Kenya surround Mt. Kasigau and depend on the mountain's cloud forest for their water supply. Five of these villages have regularly experienced water shortages, and all village water supplies were contaminated with Escherichia coli bacteria. There is a need to economically find new sources of fresh ground water. Remote sensing offers a relatively quick and cost-effective way of identifying areas with high potential for ground water development. This study used spectral properties of features on Landsat remote sensing imagery to map linear features, soil types, surface moisture, and vegetation. Linear features represented geologic or geomorphologic features indicating either shallow ground water or areas of increased subsurface hydraulic conductivity. Regarding...
Ultratrace analysis of mercury in rain water has been investigated, including recovery of ionic mercury with the addition of acids, treatment and storage and stability studies of mercury in rain water. Recovery of ionic mercury from rain water samples increased with increased acid concentrations and increased substantially with UV-irradiation. Recovery of ionic mercury in the presence of different acids was compared. Treatment studies of rain water for the analysis of total mercury were done using different decomposition methods. More than 20% of the total mercury was found in rain water residue after filtration through 0.45 ..mu..m membrane filters. Methylmercury (MM) content in filtered and unfiltered rain water however was nearly the same. On long term storage of rain water without acids at pH = 2.0 and 4.5 loss of total mercury occurred, ...
Concentrations of tritium in environmental waters (precipitation, rivers, lakes, tap water) have been determined using electrolytic enrichment and liquid scintillation counting. In waters of big rivers (the Vistula and the Odra rivers), lakes and tap water the annual average concentrations were similar to each other being from 1.4 to 1.9 Bq x dm"-"3. These concentrations were similar to those in the precipitation in which they ranged from 1.7 to 2.2 Bq x dm"-"3. The lowest tritium concentrations were found in waters of the Seashore Region rivers (average for 1994-1999 was 1.1 Bq x dm"-"3). The tritium concentrations in surface waters and in precipitation are still higher than that of natural level. The data obtained show that tritium concentration in the water of rivers might depend on the size of drainage area. The observed seasonal ...
The papers presented at the symposium had covered three general areas in which isotopes could have been beneficially used. these areas are: -Water use and water use efficiency studies. -Ground water investigations -Water problems in the arab countries. The individual papers had dealt with these subjects: -Hydrological research in the arab countries by use of radioisotopes. -The perspectives of use of radioisotopes in hydrological studies in Syria. -Water use efficiency and sub-soil water studies. -Sea water inclusion in a coast el aquifers in Lebanon. -Irrigation requirements of crops in Lebanon as determined by a Neutron probe with reference to other methods. -The use of the neutron moisture meter and other methods of the determination of the evapotranspiration of maize. -Ground water investigations, dating and nuclear ...
Coal bed natural gas (CBNG) development in the Powder River (PR) Basin produces modestly saline, highly sodic wastewater. This study assessed impacts of wetting four textural groups (0-11%, 12-22%, 23 -33%, and > 33% clay (g clay/100 g soil) x 100%))with simulated PR or CBNG water on water retention. Soils received the following treatments with each water quality: a single wetting event, five wetting and drying events, or five wetting and drying events followed by leaching with salt-free water. Treated samples were then resaturated with the final treatment water and equilibrated to -10, -33, -100, -500, or -1,500 kPa. At all potentials, soil water retention increased significantly with increasing clay content. Drought-prone soils lost water-holding capacity between saturation and field capacity with repeated wetting and drying, ...
The humidification dehumidification desalination process is viewed as a promising technique for small capacity production plants. The process has several attractive features, which include operation at low temperature, ability to utilize sustainable energy sources, i.e. solar and geothermal, and requirements of low technology level. This paper evaluates the characteristics of the humidification dehumidification desalination process as a function of operating conditions. A small capacity experimental system is used to evaluate the process characteristics as a function of the flow rate of the water and air streams, the temperature of the water stream and the temperature of the cooling water stream. The experimental system includes a packed humidification column, a double pipe glass condenser, a constant temperature water circulation tank and a chiller for cooling water. The ...
The humidification dehumidification desalination process is viewed as a promising technique for small capacity production plants. The process has several attractive features, which include operation at low temperature, ability to utilize sustainable energy sources, i.e. solar and geothermal, and requirements of low technology level. This paper evaluates the characteristics of the humidification dehumidification desalination process as a function of operating conditions. A small capacity experimental system is used to evaluate the process characteristics as a function of the flow rate of the water and air streams, the temperature of the water stream and the temperature of the cooling water stream. The experimental system includes a packed humidification column, a double pipe glass condenser, a constant temperature water circulation tank and a chiller for cooling water. The ...
Enthalpy relaxation properties of the ethylene glycol (EG) aqueous solutions confined within silica-gel void spaces of 1.1 nm in the average void thickness and 6, 12 and 52 nm in their average diameters were examined by an adiabatic calorimetry to understand the glass transition behavior of the solutions and the rearrangement processes of the molecules. The glass transition temperature Tg of EG was found to decrease with adding the water molecules which are mobile under the condition lacking in the full hydrogen-bond network. Meanwhile, the Tg in the water-rich region showed a rise towards pure water; after a phase separation in a 25 mol% (x = 0.25) EG solution, the Tg was 160 K which was higher than that derived by extrapolating the composition dependence to pure water. The Tg = 160 K is the same as observed in the pure water confined within 1.1 nm voids; this indicates the ...
Olive tree (Olea european L.) cultivation, the major tree crops in Mediterranean countries is being extended to irrigated lands. However, the limited water availability, the severe climatic conditions and the increased need for good water quality for urban and industrial sector uses are leading to the urgent use of less water qualities (brackish water and recycled wastewater) for olive tree irrigation. The aim of this work was to asses the effects of long term irrigation with treated waste water (TWW) on the soil chemical properties, on olive tree growth and on oil quality characteristics. (Author)
Object: To limit the discharge amount of reactor water in a primary system at the time of scram to prevent excessive outflow of reactor water outside the system. Structure: A signal from an upper limit position indicator detects the fact that control rods are completely inserted when the reactor is urgently stopped and the detection signal causes a valve in an outflow line of the discharge water from a control rod driving mechanism to be closed to limit the amount of discharge flown into the scram discharge vessel, thus preventing outflow of reactor water in the primary system after the scram has been initiated. (Kamimura, M.).
A full scale experiment was carried out to investigate the texture characteristics of the falling water of free falling and slope failing types. According to the increase of Reynolds number, the texture of falling water was classified into three categories for both types: stability of free surface, transition and whole turbulence. In the first category the stability of the free surface was related to the growth of minute disturbance. Surface tension works as a counter, force to the disturbance in free falling water, and gravity in slope falling water. 14 refs., 15 figs., 3 tabs.
In the development of a geothermal heat pump a water source heat pump was connected to a 1-1/2'' water line, 2200' long, buried in an endless loop 10' deep. The system is closed, circulating the same water continuously through the heat pump back to the field again. This water line 10' deep is the geothermal heat source. No matter how cold the air temperature gets on a winter day the water temperature to the heat pump will always be above 45/sup 0/F. This system has efficiently heated our house the past year using no supplemental heat.
The lakes formed in the Amazon floodplain play a key role in sustaining the highest populational density in the Amazon Basin because of its high primary productivity. The water volume in these lakes vary greatly during the year and possible water sources are the feeding river during high water state of the hydrographs and local inputs from its drainage basin. As these sources are chemically distinct, to understand the nutrient dynamics in these lakes, it is very important to know the relative water contribution of different water sources. In this paper we use "1"8O as a conservative to know the water sources for the lakes and our hypothesis is that: 1) In the high water stage lake water is derived predominantly from its feeding river. Therefore their #delta#"1"8O should be similar. 2) In the low ...
Aiming to understand the formation mechanism of dioxins in the iron ore sintering process, dust samples obtained from some windboxes of a commercial iron ore sintering plant have been characterized with a powder X-ray diffraction (XRD), by the transmission electron microscope (TEM) equipped with an electron energy loss spectroscopy (EELS), and by the temperature-programmed desorption (TPD) and temperature-programmed oxidation (TPO) techniques. The elemental and XRD analyses reveal that the content of the Cl present in the samples ranges from 0.075 mass%-dry to 5.1 mass%-dry and tends to be higher at smaller dust particles, and that some of the Cl exists as KCl with the average crystalline size between 40 nm and 50 nm. Dust samples also contain a significant amount of unburned carbon, and the smallest dust particles, < 500 {mu}m, show the highest C contents in many cases and consist partly of C, K, and Cl elements. The TPD and TPO experiments exhibit that the dust samples have ...
Photoelectrochemical oxidation is a potentially interesting method for destroying toxic organic materials. We have studied the photoelectrocatalytic activity of TiO{sub 2} films made by thermal oxidation of titanium, low pressure chemical vapour deposition (LPCVD), and anodisation of titanium. Two model organic compounds have been investigated for photooxidation: methyl phosphonic acid (MPA) which is a nerve gas analogue and 4-chlorophenol (4-CP) which is a chlorinated aromatic compound considered a standard for the evaluation of the TiO{sub 2} / UV processes. In addition to photoelectrochemical characterisation the films have been characterised by profilometry, XRD, AFM, photocurrent spectroscopy and Raman microscopy. Correlations have been made between the physical properties of the thin films and their catalytic activities. The most catalytic sample of thermally oxidised titanium was prepared at 400 deg C, and the presence of anatase was shown by XRD, MPA ...
This report summarizes the results of a dioxin/furan emissions test of a secondary-copper-recovery cupola furnace equipped with an afterburner for hydrocarbon emissions control and two baghouses for particulate-emissions control. The cupola furnace is used for recovery of copper from telephone scrap and other copper-bearing materials. The test was No. 10 in a series of dioxin/furan emissions tests conducted under Tier 4 of the National Dioxin Study. The primary objective of Tier 4 is to determine if various combustion sources are sources of dioxin/or furan emissions. If any of the combustion sources are found to emit dioxin or furan, the secondary objective of Tier 4 is to quantify these emissions. Secondary-copper-recovery cupola furnaces are one of 8 combustion-source categories that have been tested in the Tier 4 program. The tested cupola furnace, MET-A, was selected for the test after an initial information screening and a one-day pretest survey visit. Cupola furnace MET-A is a ...
A numeric method for predicting mineral ash deposition in coal dust furnaces is presented which is based on a bidirectional working time coupling of thermodynamic calculation routines (ChemApp{sup TM}) with the commercial CFD code FLUENT{sup TM}. The deposition characteristics of particles and wall surfaces is assessed on the basis of evaluations of flow simulation parameters and results of thermodynamic calculations for the mineral matter contained in the fuel particles, taking into account the complete energy, momentum and mass exchange history of the ash and the mineral conversion. The models enables calculations of the gaseous release of mineral components (e.g. alkaline substances and chlorine) from ash during combustion and its distribution inside a combustion chamber. The method and model are validated using experimental data. (orig.) [German] In der vorliegenden Arbeit wird ein numerisches Verfahren beschrieben, mit dem die Ansatzbildung in ...
Peroxisome proliferating agents (PPAs) are a structurally diverse group of chemicals that include environmental chemical contaminants such as certain chlorinated herbicides, solvents and plasticizers. PPAs have previously been shown to induce anti-trout laruci acid hydroxylase immunoreactive proteins in bluegill and catfish. In this investigation, induction of lauric acid hydroxylase activity and immunoreactive proteins was confirmed, and the mass spectral analysis of specific hydroxylation products was performed in order to identify possible species-specific differences in fatty acid metabolism. Male bluegill (Lepomis macrochirus) and channel catfish (Ictalurus punctatus) were administered clofibrate or ciprofibrate 48 hr prior to hepatic or trunk kidney (catfish only) microsome preparation. While no significant differences were observed in male catfish, male bluegill had significant decreases in hematocrit and plasma protein indicating hemodilution due to ...
Negative ions have attractive features as drivers for inertial confinement fusion, because they will avoid electron cloud effects, and could be efficiently photodetached to neutrals after the final focus, which could also be beneficial in heating warm dense matter targets. The halogens have large electron affinities, and thus should be able to produce high current densities of relatively robust negative ions. Recent experiments comparing chlorine beams to argon beams using the same source, extraction optics, and diagnostics have demonstrated that Cl"- beams can be produced with similar emittance to Ar"+ beams, and with about 34 the current density from the same configuration. The observed effective beam temperature of about 13eV, and the similarity of current densities show that negative halogen beams can meet the current density and emittance requirements of heavy ion fusion. The near equivalence of the Cl"- and Cl"++Cl_2"+ current densities reaching the Faraday ...
Doping of molecular organic materials is important for the functionality of organic electronic devices as e.g solar cells. We investigated the doping behaviour of the acceptor molecules Cl{sub 2}-DCNQI and F{sub 16}CuPc incorporated into a CuPc matrix. In-situ XPS/UPS measurements were performed on coevaporated films. Doping by Cl{sub 2}-DCNQI was not successful. The molecule lost its chlorine atoms during thermal evaporation. For pristine F{sub 16}CuPc layers we observe a strong broadening of the photoemission features with increasing deposition rate indicating different domains probably of different molecular structure of differing electric interface potential. F{sub 16}CuPc incorporated into CuPc shows sharp photoemission features. With increasing F{sub 16}CuPc content Fermi level shifts are observed in both phases. In CuPc the maximum shift is about 0.45 eV towards the HOMO level indicating p-doping. Simultaneously the Fermi level in F{sub 16}CuPc shifts 0.15 ...
The diverse microenvironments of foods, changing with processing and preservation, might provide conditions that would enhance the growth of microorganisms which are the principal cause of spoilage, off-odor and unpleasant flavor in foods. Radiation is a potential process which may provide a product with far superior microbial quality for food preservation, by reduction of microbial population; elimination of food-borne pathogens; extension of shelf-life; and reduction of spoilage. The aim of irradiation at low dose level is to eliminate certain microorganisms, especially spoilage types and those of public health significance. But, the radurization dose allows the outgrowth of radioresistant bacteria. Certain strains of Moraxella-Acinetobacter (M-A) groups have been recognized as radioresistant bacteria (Welch and Maxcy, 1975), which may have gone unnoticed by food microbiologists, since these bacteria have not been associated with problems and are present in relatively small numbers. ...
The sulfur-iodine (SI) thermochemical cycle is one of the main candidate methods to produce hydrogen from non-fossil sources like nuclear (GEN IV reactor) or solar thermal power. A major issue for the successful implementation of the SI cycle is the selection of technically viable and economic materials for construction of process components, particularly heat exchangers. Challenging conditions are encountered in each of the three sections of the SI cycle due to the corrosive chemicals present, including sulfuric acid, iodine, hydroiodic acid, sulfur dioxide, hydrogen, oxygen, and others. In Section I, aqueous, non-aqueous (liquid iodine), and gaseous multi-component phases are present at about 120 {sup o}C and 0.7 MPa. Section II involves gaseous and aqueous phases of sulfuric acid, sulfur dioxide, and oxygen at up to about 830 {sup o}C and 3.6 MPa. In Section III , aqueous, non-aqueous, and gaseous phases, at up to 310 {sup o}C and 2.2 MPa, containing iodine, hydroiodic acid, ...
A potentially new use for Illinois coal is as a fuel injected into a blast furnace to produce molten iron as the first step in steel production. Because of its increasing cost and decreasing availability, metallurgical coke is now being replaced by coal injected at the tuyere area of the furnace where the blast air enters. The purpose of this study is to evaluate the combustion of coal during the blast furnace injection process and to delineate the optimum properties of the feed coal. This investigation is significant to the use of Illinois coal in that the limited research to date suggests that coals of low fluidity and moderate to high sulfur and chlorine contents are suitable feedstocks for blast furnace injection. During the first phase of this project a number of the objectives were realized, specifically: (1) a blast furnace sampling system was developed and used successfully to collect samples inside an active furnace; (2) two sets of blast furnace samples ...
Pitting corrosion and trans-passive dissolution of 316 stainless steel in solution containing five percent of commercial bleaching liquid was investigated by employing potentiodynamic polarization method and recording corrosion potential during immersion. Today commercial bleaching liquids are widely used as cleaner additives, therefore, those house appliances made from stainless steels are in contact with aqueous solution containing bleaching liquid. This may cause sever localized corrosion and trans-passive dissolution. In order to investigate the possibility of trans-passive dissolution of stainless steel by bleaching liquid, potentiodynamic polarization and recording variation of corrosion potential of specimens were carried out in 0.2 M Na{sub 2}SO{sub 4} solution containing 5 %wt. commercial bleaching liquid. A 500 mV drop in trans-passive potential and also instantaneously ennobling corrosion potential revealed the possibility of trans-passive dissolution due to oxidizing effect ...
The performance of intermolecular potential models on the adsorption of carbon tetrachloride on graphitized thermal carbon black at various temperatures is investigated. This is made possible with the extensive experimental data of Machin and Ross(1), Avgul et al.,(2) and Pierce(3) that cover a wide range of temperatures. The description of all experimental data is only possible with the allowance for the surface mediation. If this were ignored, the grand canonical Monte Carlo (GCMC) simulation results would predict a two-dimensional (2D) transition even at high temperatures, while experimental data shows gradual change in adsorption density with pressure. In general, we find that the intermolecular interaction has to be reduced by 4% whenever particles are within the first layer close to the surface. We also find that this degree of surface mediation is independent of temperature. To understand the packing of carbon tetrachloride in slit pores, we compared the performance of the ...
SummaryIntended Outputs: Identification and evaluation, using participatory approaches, of demand management options:*Technical*Allocative and market based*Impact on target beneficiariesSupporting measures required when introducing water demand management options above:*Extension services & training*Water licences/rights*Institutional changes*Legal measures and regulation*Education*Support in diversifying to less water demanding activities*S [continued...]ObjectivesIdentification of the most appropriate demand management strategies for ground water abstraction, where aquifiers are being over-exploited, ensuring sustainable livelihoods of the vulnerable and poor are safeguarded. Poverty reduction strategies for areas where groundwater is being over-exploited.DescriptionProject Background: Groundwater is the principal source of both irrigation and domestic water supplies in many ...
In this paper nickel acetate catalyzed sodium borohydride cartridges have been prepared and hydrolyzed with water for hydrogen production. Two technological solutions have been tested to increase the overall hydrogen yield, namely a porous water diffuser and a hydrophobic membrane. The first was used to improve water diffusion inside the hydride while the second to confine water inside the cartridge. The generated hydrogen flow showed a very reproducible behavior. Hydrogen promptly evolved just after water was pumped into the cartridge. After some initial peaks, a constant hydrogen flow has been recorded for the whole reaction time. The constant flow was related to the presence of the porous diffuser. The use of a hydrophobic membrane to confine the water inside the cartridge allowed to increase the overall hydrogen yield: about 6 water ...
The effect of longer ice-free periods on the seasonal variation and total annual values of phytoplankton primary production was considered along with the efficiency and productivity of the phytoplankton communities at different water temperatures by constant light. The studied pond, Vasikkalampi, is located in the town Jvyaskyla in central Finland. The pond is slightly eutrophic and its water is used for cooling purposes by a 35 MW thermal powerplant. The cooling water is taken in the middle of the pond and it returns as heated effluent to the northern part, near the surface, about 100 m from the intake pipe. This circulation and warming of the water keeps the pond open throughout the year except during the coldest weeks in the winter when some parts freeze over. The increase of the water temperature was not sufficient to be optimal for photosynthesis in the spring. The ...
As part of the national survey to evaluate natural radioactivity in the environment, concentration levels of natural uranium and "2"2"6Ra have been analyzed in over 300 drinking water samples taken from different locations in Argentina. "2"2"6Ra was determined by "2"2"2Rn emanation and liquid scintillation counting, and natural uranium by a fluorimetric procedure. Values ranging from 0.03 to 24 #mu#g.l"-"1 of natural uranium and from 0.06 to 50 #mu#g.l"-"1, were measured on drinking water samples taken from tap water systems and private wells, respectively. Concentrations up to 15 mBq.l"-"1 and to 22 mBq.l"-"1 of "2"2"6Ra were found in drinking water samples taken from tap water systems and private wells, respectively. These values are compared with the reference values accepted for drinking water. Based on the water intake rate, the age ...
This paper explores the potential implications of climate change for the use and management of water resources in Britain. It is based on a review of simulations of changes in river flows, groundwater recharge and river water quality. These simulations imply, under feasible climate change scenarios, that annual, winter and summer runoff will decrease in southern Britain, groundwater recharge will be reduced and that water quality - as characterised by nitrate concentrations and dissolved oxygen contents - will deteriorate. In northern Britain, river flows are likely to increase throughout the year, particularly in winter. Climate change may lead to increased demands for water, over and above that increase which is forecast for non-climatic reasons, primarily due to increased use for garden watering. These increased pressures on the water resource base will ...
There are 110 million people in Sichuan Province, China. Although most of the people in cities of Sichuan use river water, which contains low levels of radon, as potable water, people in countryside and in some communities of big cities still use well water as domestic consumption. This paper reports the radon concentrations in well water investigated in four cities, i.e. Chengdu, Chongqing, Leshan and Leijiang in Sichuan Province. Of the 80 wells investigated, the radon concentrations range from 3.5 to 181.6 KBqm"-"3. Of the four cities, Chongqing has the highest well water radon concentration with the average 49.6 #+-# 54.1 KBqm"-"3 and the greatest variation. The investigation in four cities showed that the radon concentrations in well water are much higher than that in tap-water. In Chongqing where there are complex geological ...
Recycling of the spent rinse water discharged from the wet benches commonly used in semiconductor processing is one tactic for responding to the targets for water usage published in the 1997 National Technology Roadmap for Semiconductors (NTRS). Not only does the NTRS list a target that dramatically reduces total water usage/unit area of silicon manufactured by the industry in the future but for the years 2003 and beyond, the NTRS actually touts goals which would have semiconductor manufacturers drawing less water from a regional water supply per unit area of silicon manufactured than the quantity of ultrapure water (UPW) used in the production of that same silicon. Achieving this latter NTRS target strongly implies more widespread recycling of spent rinse waters at semiconductor manufacturing sites. In spite of the fact that, by most ...
Water is the most important limiting factor in the development of arid environments; therefore, optimization of water use is a necessity in desert reclamation projects. Evapotranspiration of a 6-year-old river red gum (Eucalyptus camaldulensis Dehnh.) plantation, located in a sedimentation basin of an artificial recharge of the Gareh Bygone Plain groundwater system in Iran?s southern Zagros Mountains, was studied during a 7-month period. A neutron moisture probe was used to monitor soil water changes in the root zone. Soil water depletion following rapid drainage for blocks receiving relatively high, medium and low volumes of floodwater were 809.6, 312.4, and 203.1 mm, respectively, for a 150-day period. Soil water potential during most of the study period was below ?1.5 MPa. This study pr...
The production of ozone in a negative corona discharge fed by carbon dioxide with embedded traces of oxygen and water has been studied. The presence of traces of oxygen in both pure and dry CO_2 leads to an increase in nascent ozone concentrations. In contrast, traces of water vapour (0-800 ppm) are shown to rapidly suppress ozone concentrations with the largest decreases being observed at lowest gas pressures in the discharge (300 Torr). The presence of water vapour did not considerably affect the electrical properties of negative dc corona suggesting that a chemical process is responsible for the ozone loss. We have shown that the addition of water up to a concentration of 1500 ppm has only a marginal effect on the processes of ozone formation but the catalytic cycle of ozone destruction involving OH radicals can be the reason for observed decrease in the total ozone concentration with increasing ...
In this paper we provide a geochemical investigation on 34 groundwater samples in the Mt. Vulture volcanic aquifer representing one of the most important groundwater resources of the southern Italy pumped for drinking and irrigation supply. The present study includes the first data on the abundance and mobility of minor and trace elements and the thermodynamic considerations on water-rock interaction processes in order to evaluate the conditions of alkali basalt weathering by waters enriched in magma-derived CO2. The results highlight the occurrence of two hydrofacies: bicarbonate alkaline-earth and alkaline waters deriving from low-temperature leaching of volcanic rocks of Mt. Vulture, and bicarbonate-sulfate-alkaline waters (high-salinity waters) related to prolonged water circulation in...
Cooling waters from eleven geographically disparate power plants were tested for the presence of Naegleria fowleri and Legionella pneumophila (LDB). Control source waters for each plant were also tested for these pathogens. Water from two of the eleven plants contained pathogenic Naegleria, and infectious Legionella were found in seven of the test sites. Pathogenic Naegleria were not found in control waters, but infectious Legionella were found in five of the eleven control source water sites. Concentrations of nitrite, sulfate, and total organic carbon correlated with the concentrations of LDB. A new species of Legionella was isolated from one of the test sites. In laboratory tests, both Acanthamoeba and Naegleria were capable of supporting the growth of Legionella pneumophila.
Water vapor is well known to be a critical component in many aspects of atmospheric research, such as radiative transfer and cloud and aerosol processes. This requires both improved measurements of the columnar water vapor and its profiles in the atmosphere in a wide range of conditions, and adjustment of water vapor parameterizations in radiation codes including the perfection of spectroscopic parameters. In this paper we will present the results of comparison of our calculations and downward solar fluxes measured with Rotating Shadowband Spectroradiometer under conditions of horizontally homogeneous clouds. We also will discuss the sensitivity of atmospheric radiation characteristics to variations of water vapor in the band 940 nm: these results may be useful for development of new methods of retrieval of the total column water vapor content (WVC) in the atmosphere from data of ...
A wet air oxidation (WAO) process was applied to four selected pharmaceuticals (metoprolol, naproxen, amoxicillin, and phenacetin) individually dissolved in ultra-pure water, varying the temperature and oxygen pressure. Due to the moderate (amoxicillin) or low (metoprolol, naproxen, and phenacetin) efficiency found in the oxidation of these pollutants, a catalytic wet air oxidation (CWAO) process was then tested using a platinum catalyst supported on multi-walled carbon nanotubes (CNT). In this CWAO process, the pharmaceuticals were dissolved together in ultra-pure water and in four natural water matrices-a reservoir water, a groundwater, and two waters from different municipal wastewater treatment plants. On the basis of the measurements of their removals, a discussion is given of the inf...
Counter-current regeneration of 2-stage sodium zeolite softeners has been employed in reducing hardness leakage level of steamflooding water to less than 1 ppm when raw water contains as much as 5,000 ppm of the total dissolved solids. Hardness leakage is caused by sodium displacement of calcium and magnesium from the bottom of the exchanger bed. This study presents nomographs providing for rapid calculations to be made, for which a convenient operational mode does not already exist. The nomographs relate the hardness leakage as a function of salt quality and influent water quality and present solutions for predicting the leakage level, salt quality requirement or the treatability of raw water required for steamflooding projects.
An energy saving self-powered industrial dehumidifier for use in a building having a tap water conduit leading from a source of supply to utilization points is described comprising: a dehumidifying apparatus positioned in a stream of air to be dehumidified in the building. The dehumidifying apparatus comprising conduit means for diverting at least a portion of a relatively continuously moving stream of tap water from the tap water conduit through a heat exchanger positioned in a stream of air and returning the diverted portion to the tap water stream upstream of the utilization points. Water vapor in the stream of air will condense onto the heat exchanger when the tap water has a temperature below a dew point temperature of the air stream, thereby dehumidifying the air stream.
This paper explores the through-/in-plane characteristics of water transport in the cathode gas diffusion layer (GDL) of a polymer electrolyte fuel cell (PEFC). Theoretical analysis is performed on the non-isothermal two-phase flow under flow channels. A dimensionless group Da (Damkohler number for PEFC operation), defined as the ratio of water generation rate to water vapor-phase removal rate, is formulated to characterize the flow regimes in a PEFC. This group, lumping geometrical parameters and physical properties, compares the water vapor-phase removal capability (via water diffusion and holding capacity) with the rate of water production by the oxygen reduction reaction. We find that this dimensionless group can be used to characterize the non-isothermal, two-phase phenomena: when Da&...
Trace elements were extracted from a coal-fired power plant electrostatic precipitator ash with nitric acid, hydrochloric acid, citric acid, redistilled water, and ammonium hydroxide as extractants. Effluent waters at this plant were sampled to assess the elevation of trace element concentrations compared with intake waters. The results showed a positive correlation between those elements most extractable by water (B, F, Mo, and Se) or acid (As, B, Cd, F, Mo, and Se) and those elements most elevated in effluent waters (As, B, F, Mo, and Se).
Effect of water injection/draining on elastic waves penetrating through cracks is examined by measuring elastic waves before, during, and after the injection/draining of water into/from cracks in presence in granite. Two blocks of rock, with their crack-containing surfaces in contact with each other, are placed in a vessel, and water injection/draining is done through a hole on a vessel bottom side so that water will penetrate into the cracks. When the blocks are dry, there is almost no contact between the cracks, and so no crack penetrating waves are observed. Crack penetrating waves are produced when water is injected, and the position of the receiver sensing the penetrating waves changes as the water level rises. When the water level is lowered from the high water level, the waveform changes again as the level ...
Vulnerability to xylem embolism by freeze-thaw cycles and water stress was quantified in ring-porous (Quercus gambelii Nutt.), diffuse-porous (Populus tremuloides Michx.,...Full Text Available
Water relations of growing segments of maize (Zea mays L.) coleoptiles were investigated with osmotic methods using either mannitol (MAN) or polyethylene glycol 6000 (PEG) as external...Full Text Available
Spin-lattice relaxation rates of protein and water protons in dry and hydrated immobilized bovine serum albumin were measured in the range of 1H Larmor frequency from 10 kHz to 30...Full Text Available
We analyzed the effect of short-term water deficits at different periods of sunflower (Helianthus annuus L.) leaf development on the spatial and temporal patterns of tissue expansion...Full Text Available
Between 1970 and 1975, the incidence of new Schistosoma mansoni infections was reduced in 5 villages after each household was provided with its individual water supply and community...Full Text Available
A formula and technology are presented for the preparation of a hydrolyzed polyacrylonitrile (gipane) from the wastes of chemical production, analysis of the results of working to use them to insulate influxes of water in the extracting wells of the Sokolovogorskiy field.
For terrestrial animals and plants, a fundamental cost of living is water vapor lost to the atmosphere during exchange of metabolic gases. Here, by bringing together previously developed models for...Full Text Available
USGS - science for a changing world USGS Home Contact USGS Search USGS USGS Water-Quality Information * Home * Data * Methods * Labs * Publications * Topics * Programs * Contact Us...
All energy scenarios show a shift toward an increased percentage of renewable energy sources, including biomass. This study gives an overview of water footprints (WFs) of bioenergy from 12 crops that...Full Text Available
Assessments of drinking water safety rely on the assumption that ingestion represents the principal route of exposure. A review of the experimental literature revealed that skin penetration rates for...Full Text Available
Small-angle X-ray scattering (SAXS) is used to demonstrate the presence of density fluctuations in ambient water on a physical length-scale of ≈1 nm; this is retained with decreasing temperature...Full Text Available
The effects of consuming water with meals rather than drinking no beverage or various other beverages remains under-studied. This systematic review of English language studies compared the effects...Full Text Available
A previous report of high levels of members of the domain Archaea in Antarctic coastal waters prompted us to investigate the ecology of Antarctic planktonic prokaryotes. rRNA hybridization...Full Text Available
Though central to our understanding of how roots perform their vital function of scavenging water and solutes from the soil, no direct genetic evidence currently exists to support the foundational model...Full Text Available
A barley (Hordeum vulgare L.) mutant (Az34) has been identified with low basal levels of abscisic acid (ABA) and with reduced capacity for producing ABA in response to water stress....Full Text Available
BackgroundStudies using transthoracic thermodilution have demonstrated increased extravascular lung water (EVLW) measurements attributed to progression of edema and...Full Text Available
Radionuclide X-ray fluorescence analysis was used for the determination of iron, calcium, potassium, copper, manganese and zinc in waste water from the production process of citric acid.
Radionuclide X-ray fluorescence analysis was used for the determination of iron, calcium, potassium, copper, manganese and zinc in waste water from the production process of citric acid. (author).
This guide describes an acceptable method of complying with the Commission's regulations with regard to the quality assurance requirements for the packaging, shipping, receiving, storage, and handling of items for water-cooled nuclear power plants.
Polyamine oxidase was purified to homogeneity from leaves of water hyacinth by the criterion of sodium dodecyl sulfate gel electrophoresis (SDS disc PAGE). The enzyme showed a high specificity for spermidine...Full Text Available
Conference paper regarding research in freeze-protection methods that could extend market acceptance for passive solar domestic water heating systems in more northern climates if the U.S.
The purpose of the piezometer network is to establish baseline hydraulic head data for the water table aquifer at the F- and H-Area seeplines prior to startup of the groundwater extraction/injection remediation system.
Both DOE and DOD use water and/or steam in the process of removing high explosives, resulting in large quantities of contaminated water, which is then run through activated carbon, which then has to be decontaminated. Research has been underway to utilize microorganisms to degrade RDX and HMX.
A method is proposed for operating bed waters in an oil well by injecting silanes into the near-face zone. It is distinguished by the fact that in order to improve the effectiveness of insulation, the silanes used are silanes of general formula Si /SUB n/ H /SUB 2n-n/ .
Three Legionella-like organisms were isolated from water from the cooling towers of two Australian institutions. The strains grew on buffered charcoal-yeast extract (BCYE) agar but not on BCYE agar...Full Text Available
The water permeability of tissues was investigated by measuring the efflux of 3HHO from previously loaded (in darkness) etiolated bean buds (Phaseolus vulgaris L. var. Red...Full Text Available
This patent describes a nuclear system comprising a containment airspace in which a nuclear reactor pressure vessel is disposed there being a reactor core within the pressure vessel. It comprises a heat exchanger elevated a distance above the pressure vessel; a pool of water surrounding the heat exchanger; means for venting the pool of water to an environment outside the containment; a heat exchanger entry conduit within the containment, the entry conduit having an open lower end communicating with the containment space, and an upper end connected to the heat exchanger, water-containing heated fluid present in the containment airspace incident a pressure vessel loss of coolant event entering and flowing through the entry conduit into the heat exchanger for cooling the fluid to convert water vapor therein to a condensate and separate non-condensable gasses therefrom; a gravity driven cooling ...
Production treatment chemicals represent a diverse collection of chemical classes, added at various points from the wellhead to the final flotation cell, to prevent operational upsets and enhance the separation of oil from water. Information in the literature indicates that while many treatment chemicals are thought to partition into oil and not into the produced water, there are cases where a sufficiently water soluble treatment chemical is added at high enough concentrations to suggest that the treatment chemical may add to the aquatic toxicity of the produced water. A study was conducted to evaluate the potential effect of production treatment chemicals on the toxicity of produced waters using the US EPA Seven-day Mysidopsis bahia Survival, Growth and Fecundity Test. Samples of produced water were collected and tested for toxicity from three platforms under ...
For the inventory of water tritium concentration in the Manche department, it is the complementarity that animated the work opened during year 2001. To answer to a commune sensitivity such water quality, particularly drinking water at tap, the A.C.R.O. laboratory brought its know how to make and its technical means in the area of tritium analysis and the general council brought its know how to make and its logistics means in matter of sanitary control. This collaboration has allowed to supply an indication on the tritium content of the distribution waters of thirty of the most important cities of the department. Then, it allowed to inform on the radiological situation (in relation with the tritium presence) of coast waters and principal rivers waters. More than 160 controls have been realised between the months of march 2001 and february 2002. Only the tritium ...
A field experiment was conducted during the summer of 1988 to test the hypothesis that water deficit affects the abscisic acid (ABA) and indole acetic acid (IAA) concentrations in cotton (Gossypium...Full Text Available
Water samples from several ponds in Minnesota were evaluated for their capacity to induce malformations in embryos of Xenopus laevis. The FETAX assay was used to assess the occurrence of malformations...Full Text Available
Various methods to analyse the effect of a non-isotherme water injection on the pressure evolution during a test on a double geothermal well are investigated. Then, several types of injection test are simulated with experimental data to examine the condit...
The Idaho Chemical Processing Plant (ICPP) Water inventory Study was initiated in September 1993 with the formation of a joint working group consisting of representatives from DOE-ID, State of Idaho INEL Oversight Program, US Geological Survey, and INEL employees to investigate three issues that had been identified by the INEL Oversight Program at ICPP: (1) the water inventory imbalance at ICPP, (2) the source of water infiltrating into the Tank Farm vault sumps, and (3) the source of water providing potential recharge to perched water bodies underlying ICPP. These issues suggested that water was being lost from the ICPP distribution system. The INEL Oversight Program was concerned that the unaccounted for water at ICPP could be spreading contaminants that have been released over the past 40 years of operations of ICPP, possibly to the Snake ...
Environmental targets and saving energy have become ones of the world main concerns over the last years and it will increase and become more important in a near future. The world population growth rate is the major factor contributing for the increase in global pollution and energy and water consumption. In 2005, the world population was approximately 6.5 billion and this number is expected to reach 9 billion by 2050 [United Nations, 2008. (www.un.org), accessed on July]. Water supply systems use energy for pumping water, so new strategies must be developed and implemented in order to reduce this consumption. In addition, if there is excess of hydraulic energy in a water system, some type of water power generation can be implemented. This paper presents an optimization model that determines the best hourly operation for 1 day, according to the electricity tariff, for a pumped ...
Objectives. Thousands of Louisiana residents were asked to boil water because of widespread disruptions in electricity and natural gas services after Hurricane Rita. We sought to assess...Full Text Available
Wet-weather flow (WWF), including combined-sewer overflow (CSO, sanitary-sewer overflow, and stormwater (SW), is a significant contributor of microbial contamination to surface water and ground water. By using effective wastewater or SW disinfection, introduction of pathogen con...
Global Soil Water Holding Capacity Dataset from UNEP/GRID. Entry ID: GNV0025 ... Dao at unep.org. Contact Address: Head of Metadata & Socio-Economics Unit ...
Severance of the ureter beyond the renal papilla causes a fall in urinary osmolality, which suggests that exchange of water or solute between urine and renal parenchyma normally occurs in the intact...Full Text Available
Along with the shrinkage of LSI geometries, a higher quality of ultrapure water has been continuously required. Analytical technology for ultrapure water has also progressed before ultrapure water production technology improvements. In this study, we performed optimization of the analytical conditions for the direct analysis of acid droplets, and established an analytical technology for measurements of trace amounts of metallic impurities deposited on a wafer surface by means of Vapor Phase Decomposition (VPD)/Inductively Coupled Plasma Mass Spectrometry (ICP-MS). As a result, analytical technology for metallic elements of the 1x10"8 atoms/cm"2 level on wafer surface has been established. By applying analytical technology to the wafer that has been contacted with ultrapure water, a new evaluation technology for ultrapure water quality by means of wafer surface contamination has been ...
In the period November 1, 1985 to January 31, 1986, 703 cases of giardiasis were reported in Pittsfield, Massachusetts (population 50,265). The community obtained its water from two main reservoirs...Full Text Available
Hydrolysis of olive oil by Chromobacterium viscosum lipase was studied in a reverse micellar system of a anionic surfactant Aerosol OT (AOT) and isooctane. Different methods of solubilization of the micellar system afford specific dependence of enzymatic activity of the lipase on the water content in the micelles. In an injection method, water content is controlled by the amount of injected water, which determines the micelle size and hydrophobicity of the micelle without salt addition and changes reversibly the conformation of lipase corresponding to the change of lipase activity. The activity reaches the maximum at a water content (water/AOT)of 7. In a phase transfer method, water content is determined by salt concentration in the aqueous phase in contact with micelles and the water content corresponding to the maximum activity is 12 to ...
The dispersion mechanism of highly loaded coal-water mixture (CWM) in the presence of a polyelectrolyte additive was investigated. Two important factors have been found: the ability of the additive to apply a sufficient electric repulsive force to the coal particles, and an appropriate affinity of the additive to the coal surface.
... 03, 2001 | Rate It Lake Superior Streams http://www.lakesuperiorstreams.org/ (1 vote) interactively examine real-time water quality data from 5 ...north shore Lake Superior trout streams and learn about other streams in the region, how they \\
A numerical technique is developed for estimating water quality violation frequencies due to pollutant discharges from urban areas during combined sewer overflow events. The first four moments of in-stream pollutant concentration are found by integrating a pollutant loading - wat...
The effect of plant water deficit on ethylene production by intact plants was tested in three species, beans (Phaseolus vulgaris L.), cotton (Gossypium hirsutum L.)...Full Text Available
We discuss the relationship between the dynamically changing tension gradients required to move water rapidly through the xylem conduits of plants and the proportion of conduits lost through embolism...Full Text Available
Cited are the results of physico-chemical studies and industrial tests of a copolymer of methacrylic acid and diethylammonium salt, used for limiting the influx of stratum waters into a well.
Measurement of local steam condensation rates of cocurrent stratified flow of steam and subcooled water was carried out at atmospheric pressure in a horizontal rectangular channel. The channel was constructed of stainless steel with pyrex glass windows, a...
We explored the association between groundwater radon levels and childhood cancer mortality in North Carolina. Using data from two state-wide surveys of public drinking water supplies, counties were...Full Text Available
Feb 15, 2008 ... hydrological properties (e.g., hydrometeor budgets, cloud ice/water, transports ... cloud fraction, mass and particle size. In combination, these .... anomaly in the LS is not simply due isentropic movement of water vapor relative ...
The population masses in many coastal zones in Japan, and human activities are greatly effected. The representative water area is the Tokyo Bay. The population of the Tokyo Bay reaches 26 million at present, and a mass of organic substance and nutrient salt flow into it through rivers and sewage-treatment plants, etc. With the improvement of pollution source countermeasure and sewerage in the area, the inflow load to the Bay gradually decreases, but in the inner bay, red tide is generating in the summertime mainly. And, the anoxic water areas observed in bottom layer in summertime make large effects on the seafood. It is a large theme to clarify formation process of the anoxic water area and to solve this problem for the Tokyo Bay in the twenty-first century. In this paper, changes in water qualities and human activities and fundamental approach of water quality conservation of the ...
Initial results obtained with a Monte Carlo computer program designed to link initial physical events in irradiated liquid water with subsequent chemical and biological events are presented. 10 refs., 4 figs., 3 tabs.
An earlier representation of the radial distribution of dose about the path of a heavy ion in liquid water is modified and extended to include silicon, lithium fluoride, and sodium iodide. 6 refs., 5 figs., 1 tab.
The current primary standards at NPL for the measurement of absorbed dose to water in high energy photon and electron beams are graphite calorimeters. However, the quantity of interest in radiation dosimetry is absorbed dose to water. Therefore, a new absorbed dose to water standard based on water calorimetry has been developed for use in high energy photon and electron beams. The calorimeter operates at 4 deg C, with temperature control being provided by liquid cooling. The sealed glass inner vessel of the calorimeter was designed to minimise the effect of non-water materials on the measurement of absorbed dose. The temperature sensing thermistor probes were designed and constructed so that glass is the only material in contact with high purity water inside the vessel. Initial measurements of absorbed dose to water made in 6, 10, and 19 MV ...
Systematic observations of man/water contact in a valley endemic for S. mansoni in St Lucia were carried out prior to the introduction of a household water supply. The observations...Full Text Available
The steam generator low water level trip setpoint of KORI NPP units 3 and 4(KNU 3 and 4), three-loop Westinghouse pressurized water reactor, is higher than that of OPR1000. In addition, steam generator downcomer water level in KNU 3 and 4 could fluctuate easily during a transient because of smaller downcomer water inventory, compared to the total water inventory in the steam generator. Due to these reasons, there is a higher possibility of unnecessary reactor trips caused by the steam generator low-low water level in KNU 3 and 4. Its operating history shows that most of reactor trips were caused by steam generator low-low level reactor trip signal. Such reactor trips, especially unnecessary ones, result in time and economic losses. In this paper, a feasibility study was performed to reduce unnecessary reactor trip by changing steam generator low-low ...
The steam generator low water level trip setpoint of KORI NPP units 3 and 4(KNU 3 and 4), three-loop Westinghouse pressurized water reactor, is higher than that of OPR1000. In addition, steam generator downcomer water level in KNU 3 and 4 could fluctuate easily during a transient because of smaller downcomer water inventory, compared to the total water inventory in the steam generator. Due to these reasons, there is a higher possibility of unnecessary reactor trips caused by the steam generator low-low water level in KNU 3 and 4. Its operating history shows that most of reactor trips were caused by steam generator low-low level reactor trip signal. Such reactor trips, especially unnecessary ones, result in time and economic losses. In this paper, a feasibility study was performed to reduce unnecessary reactor trip by changing steam generator low-low ...
The paper presents results of measurements of the natural radioactivity of tap water where samples were taken in front of, and behind the ceramic filter commonly used in houses for the purification of tap water. Altogether, 289 samples were taken, processed and measured during 1985-1986 in Kuwait. Results reveal the fact that ceramic filters reduce substantially the natural radioactivity in water (the 'gross' alpha activity reduced by the factor 2.18 #+-# 18%; the 'gross' beta by 1.53 #+-# 1.6%. (author).
... values and unless special precautions and equipment are used, it would be very difficult to service and maintain operational jet-fuel systems with ...
A study of stress corrosion cracking susceptibility of Zircaloy-4 in chloride-containing aqueous methanolic media is presented. The influence of water content is investigated in the 5-100 vol. % water range. The dependence of stress corrosion cracking on potential is evidenced. A close correlation is established with pitting susceptibility determined by a statistical analysis of induction times. A correlation with the repassivation potential is observed in the water-rich solutions. In the low water content solutions, two repassivation curves are determined according to the experimental technique. Pit morphology and fractography show a transition from aqueous to organic media. (author).
For light water reactors, loss of coolant is an important point in safety analysis, whereas for gas-cooled reactors the ingress of water into the core region is an incident of safety relevance. The applicability of the computer code system GAMTEREX to pebble beds of spherical high-temperature gas-cooled reactor fuel elements with simulated water ingress is verified by experiment. The measurements were performed at a Siemens-Argonaut reactor, using its ring core as a driver zone for a pebble-bed core in the center of the reactor.
The major feed-water line break accident is re-analyzed, which is based on Guangdong Daya Bay nuclear power station final safety analysis report, to justify the impacts of the decreasing of auxiliary feed-water flow rate on the safety margin in Daya Bay. The results showed that the accident analysis can meet the demands of acceptance criteria with the auxiliary feed-water flowrate decreasing from 45 m"3/h to 41.8 m"3/h, and enough safety margin is still retained
... small water or ice particles by impaction ... flight recording; principally the hydrometeor charge unit ... capability of directing aircraft movements by radio ...
We describe a compact ultrafiltration system for the removal of pyrogens and bacteria from water labeled with the stable isotopes of deuterium and oxygen-18. The ultrafiltration system is constructed from readily available commercial components and can achieve complete removal of pyrogens and bacteria from 1L contaminated water within 30 min. By use of our procedure, loss of the isotopically labeled water by retention in the filtration system was minimal. The purified water is suitable for both oral and intravenous administration to healthy human subjects participating in nutrition studies.
Makeup water is distilled internally in an amine gas treating unit by adding it to the reclaimer used to process a slipstream of lean amine from the stripper.
... 2-93 An Atmospheric Particle Emits Electromagnetic ... atmospheric water vapor produces a hydrometeor. ... subject to wind movement (either blowing ...
In Situ Bioremediation (ISB) is the term used in this report for Gaseous Nutrient Injection for In Situ Bioremediation. This process (ISB) involves injection of air and nutrients (sparging and biostimulation) into the ground water and vacuum extraction to remove Volatile Organic Compounds (VOCs) from the vadose zone concomitant with biodegradation of the VOCs. This process is effective for remediation of soils and ground water contaminated with VOCs both above and below the water table. A full-scale demonstration of ISB was conducted as part of the Savannah River Integrated Demonstration: VOCs in Soils and Ground Water at Nonarid Sites. This demonstration was performed at the Savannah River Site from February 1992 to April 1993.
The effects of variable hardness, pH, alkalinity, humics, and suspended clay on the chemical speciation of copper and its toxicity to fathead minnow larvae in Lake Superior water were investigated. Two proposed methods (toxicity factors and chemical speciation) for predicting LC50 values in specific natural waters from laboratory toxicity data and the average site specific values of general water quality parameters were evaluated. The accuracy of the cupric ion-selective electrode in determining CU/sup +2/ activities in ambient and chemically altered Lake Superior water was also determined.
A small scale biomass metal contacting experiment was performed to screen the optimal plant species for biosorption and bioaccumulation of cadmium, zinc, nickel, lead, and copper. Experiments were also conducted to test the ability of the biomass to lower the metal concentrations below the US Environmental Protection Agency surface water discharge criteria. The minimum residual concentration was 0.1 mg/L for zinc, 0.004 mg/L for lead, and about 0.01 mg/L for cadmium, nickel, and lead. Results indicate that water milfoil can be used for bioremoval of metals.
The susceptibility of CHN35VT-VD and 08CH18N10T stainless steels to stress corrosion cracking in water environment, simulating water solution found in threaded holes, was investigated using rising load line displacement tests of precracked C(T) specimens. To judge the role of oxidant on stress corrosion cracking of both stainless steels, the effect of dissolved oxygen content (fully deaerated water, water aerated at the beginning of the test) was studied. 7 refs.