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61.
Energy issues are important and consumption is slated to increase across the globe in the future. The energy-environment nexus is very important as strategies to meet future energy demand are developed. To ensure sustainable growth and development, it is essential that energy production is environmentally benign. There are two temporal issues??one that is immediate, and needs to address the environmental compliance of energy generation from fossil fuel sources; and second that is the need to develop newer alternate and more sustainable approaches in the future. Aerosol science and technology is an enabling discipline that addresses the energy issue over both these time scales. The paper is a review of aspects of aerosol science and engineering that helps address carbon neutrality of fossil fuels. Advanced materials to meet these challenges are discussed. Future approaches to effective harvesting of sunlight that are enabled by aerosol studies are discussed.  相似文献   
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Environmental Geochemistry and Health - Unfortunately, in the original publication of the article, Prof. Yong Sik Ok’s affiliation was incorrectly published. The author’s affiliation is...  相似文献   
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Blends of zein and nylon-6 (55?k) in formic acid were used to produce solution cast films and electrospun fibers. When the amount of nylon-6 was 8?% or less blends were formed that had improved tensile strength and reduced solubility. The blends were analyzed using physical property measurements, DSC and IR spectra. Using between 2 and 8?% nylon-6 provided a 33?% increase in tensile strength. Young??s modulus increased by over 50?% in this range. In general elongation was lower for all formulations. Surprisingly the cast films having 0.5?C8?% nylon-6 had improved solvent resistance to 90?% ethanol/water. Electrospun fibers were produced from formic acid solutions of zein and nylon-6 where the amount of nylon was 0, 2 and 6. Fibers produced from 27?% spinning solids had average diameters on the order of 0.5???m. Reducing the spinning solids to 21?% provide slightly smaller fibers however, the fibers had more defects.  相似文献   
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Based on a systematic review of 17 recent substance flow analyses of phosphorus (P) at the regional and country scales, this study presents an assessment of the magnitude of anthropogenic P storage in the agricultural production and the waste management systems to identify the potential for minimizing unnecessary P storage to reduce the input of P as mineral fertilizer and the loss of P. The assessment indicates that in case of all (6) P flow analyses at the regional scale, the combined mass of annual P storage in the agricultural production and the waste management systems is greater than 50 % of the mass of annual P inflow as mineral fertilizer in the agricultural production system, while this is close to or more than 100 % in case of half of these analyses. At the country scale, in case of the majority (7 out of 11) of analyses, the combined mass of annual P storage in the agricultural production and the waste management systems has been found to be roughly equivalent or greater than 100 % of the mass of annual P inflow as mineral fertilizer in the agricultural production system, while it ranged from 30 to 60 % in the remaining analyses. A simple scenario analysis has revealed that the annual storage of P in this manner over 100 years could result in the accumulation of a massive amount of P in the agricultural production and the waste management systems at both the regional and country scales. This study suggests that sustainable P management initiatives at the regional and country scales should put more emphasis on minimizing unwanted P storage in the agricultural production and the waste management systems.  相似文献   
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The metabolic fate of mancozeb in tomato (Lycopersicon esculentum Mill.) fruits was evaluated. Results indicate rapid dissipation of mancozeb and its metabolic conversion to ethylenethiourea (ETU), the carcinogenic metabolite. Treatment with mancozeb at flowering stage resulted translocation of ETU in newly emerged fruits indicating the systemic nature of ETU. ETU was detected within one hour of final spraying of mancozeb at the doses of 1.5 and 3?kg a.i./ha. The residue level of ETU increased up to 3-day for both the treatments, which then rapidly dissipated to safer metabolite ethyleneurea (EU) and reached the below detectable limit within 25 days. Cooking of fresh tomatoes caused decontamination of mancozeb residues, which was associated with simultaneous increase in ETU residues. The degradation pattern of ETU after application of mancozeb was slower as compared to the spraying of ETU as such on the crop. A pre-harvest interval of 25 days is recommended.  相似文献   
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Summary A study was conducted to analyse the causes of death during the period January 1985 to December 1989, in pashmina kids and goats thought to be acclimatised to a medium altitude climate. In general, mortality was higher during the rainy season (up to 62 percent) than in the winter (17 percent) and summer seasons (21 percent). An exception was the year 1987 when mortality was lowest in the rainy season, presumably due to the effects of a drought. During the rainy season the majority of 6–12 month-old kids became dull, off-feed, weak, emaciated and anaemic. Occasionally these animals showed nasal discharge and diarrhoea. Haematological examination of randomly selected animals during rainy, post-rainy and early-winter seasons in 1985, 1986 and 1989 showed very low red blood cell counts (RBC), haemoglobin (Hb) and packed cell volume (PCV); with elevated erythrocytic sedimentation rates (ESR), neutrophilia, relative lymphopaenia, eosinopaenia, hypoproteinaemia, hypoalbuminaemia, hypogamaglobinaemia, increased A:G ratio and hypoglycemia. Red blood cells showed piokilocytosis, anisocytosis, punched out or ring shapes, presence of erythroblasts, basophilic stippling and Anaplasma marginale.Post-mortem examination revealed lesions of parasites either singly or in combination. These included lice, coccidia, Moniezia expansa, Haemonchus contortus,and Trichuris ovis.Poor or slightly improved health state, anaemic blood picture and moderated mortality were witnessed 45 days post-treatment or during the post-rainy season. Early-winter studies indicated that the goats were in an excellent health condition with normal blood picture and negligible mortality. It was concluded that the higher mortality in pashmina goats during the rainy season was association with high rainfall, humidity, partial or zero grazing, confinement of goats in sheds (all environmental stresses) and parasitism. This was supported in 1987, when the lowest mortality occurred during the rainy season due to the effect of drought and the absence of environmental stresses.Dr R. Somvanshi is a veterinary pathologist and is in charge of the Clinical Pathology and Medicine Section of Livestock Production Research. Dr J.C. Biswas works in the Animal Genetics and Breeding Laboratory. Dr B. Sharma is a biochemist in the Division of virology and currently a post-doctoral fellow at the Department of Virology at the Karolinska Institute, Stockholm, S-10521, Sweden. Dr G.L. Koul works in the Animal Genetics and Breeding Laboratory as Principal Scientist. All are based at the Indian Veterinary Research Institute.  相似文献   
70.
Source resolution and risk apportionment of emission source categories for risk reduction purposes can be used to enhance the Bubble Policy of the Clean Air Act. This is performed by incorporating receptor modeling techniques of factor analysis and chemical mass balances to assess noncarcinogenic and carcinogenic inhalation risks to a target population for certain pollutants coming from major emission source categories in a steel plant air shed. Source resolution, using factor analysis, statistically interprets a “source” from ambient data. By subsequently quantifying risks from identified metal emission sources using chemical mass balances and risk apportionment, a total additive risk from main source contributors in the steel plant is estimated. From this methodology, the Bubble Policy can be enhanced by targeting only main risk sources or by “risk-trading” with minor impact sources to reduce the total risk (if deemed significant) without arbitrarily reducing risk for all sources in an industrial source complex’s “bubble.”  相似文献   
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