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291.
Gungor and Gupta [1999, Issues in environmentally conscious manufacturing and product recovery: a survey. Computers and Industrial Engineering, 36(4), 811–853] presented an important review of the development of research in Environmentally Conscious Manufacturing and Product Recovery (ECMPRO) and provided a state of the art survey of published work. However, that survey covered most papers published through 1998. Since then, a lot of activity has taken place in EMCPRO and several areas have become richer. Many new areas also have emerged. In this paper we primarily discuss the evolution of ECMPRO that has taken place in the last decade and discuss the new areas that have come into focus during this time. After presenting some background information, the paper systematically investigates the literature by classifying over 540 published references into four major categories, viz., environmentally conscious product design, reverse and closed-loop supply chains, remanufacturing, and disassembly. Finally, we conclude by summarizing the evolution of ECMPRO over the past decade together with the avenues for future research.  相似文献   
292.
A novel deterministic multi-period mixed-integer linear programming (MILP) model for the power generation planning of electric systems is described and evaluated in this paper. The model is developed with the objective of determining the optimal mix of energy supply sources and pollutant mitigation options that meet a specified electricity demand and CO2 emission targets at minimum cost. Several time-dependent parameters are included in the model formulation; they include forecasted energy demand, fuel price variability, construction lead time, conservation initiatives, and increase in fixed operational and maintenance costs over time. The developed model is applied to two case studies. The objective of the case studies is to examine the economical, structural, and environmental effects that would result if the electricity sector was required to reduce its CO2 emissions to a specified limit.  相似文献   
293.
Agricultural production in the state of Alabama, USA, is mostly rain-fed, because of which it is vulnerable to drought during growing season. Since Alabama receives a significant portion of its annual precipitation during winter months, the goal of this study was to evaluate the feasibility of water withdrawal from streams during winter months for irrigation in the growing season. The Soil and Water Assessment Tool (SWAT) was used to estimate the quantity of water that can be sustainably withdrawn from streams during winter high flow periods. The model was successfully calibrated and validated for surface runoff, base flow, and total stream flow. The stream flows generated by the model at several locations within the watershed were then used to examine how much water can be sustainably withdrawn from streams of various orders (first, second and third). Although there was a considerable year-to-year variability in the amount of water that can be withdrawn, a 16-year average showed that first, second, and third order streams can irrigate about 11.6, 10.3, and 10.6% of their drainage areas, respectively. The percentage of drainage area that can be irrigated was not a function of stream order.  相似文献   
294.
Soybean (Glycine max L. Merril) cv. 'Williams' plants were exposed 0.0, 0.05, 0.2 and 0.4 microl litre(-1) NO(2) under controlled environment. Amount of abscisic acid (ABA) was measured after either 7 h or 5 days of exposure as well as after 18 h of recovery period. For quantitative analysis of ABA enzyme-linked immunosorbent assay was used. A significant increase (160%) was observed in plants treated with 0.4 microl litre(-1) NO(2) for 5 days compared to an increase of only 82% on exposure for 7 h. Rate of recovery for plants treated with low doses of NO(2) was higher than those treated with higher doses.  相似文献   
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Monitoring observations made on 60 operators involved in pesticide application work in godowns and warehouses and 60 matched control workers are reported. Occupational exposure history and medical history are noted. Biochemical investigations, plasma and RBC cholinesterase estimations are included along with medical examination of the workers. Workers were found to be mostly exposed to Celphos, DDVP, Malathion, Pyrethrum, etc, and the use of protective devices were very limited. Cases of significant reduction in plasma and RBC cholinesterase activity were found. Frequency of symptoms like dizziness, headache, lachrymation, burning sensation in eyes, nausea and anorexia, etc, were much more in the exposed workers. No cases of clinical poisoning attributable to occupational exposure to pesticides were reported by the workers.  相似文献   
299.
Two commercially available enzyme-linked immunosorbent assay (ELISA) kits that are commonly used for tylosin or tetracycline residues in meat and milk were adapted for ultratrace analysis of these antibiotics in surface and ground waters. These two antibiotics are commonly fed to swine, turkeys, and cattle at subtherapeutic doses for growth promotion purposes. Both ELISA techniques were found to be highly sensitive and selective for the respective antibiotics with detection limits of 0.10 and 0.05 microg L(-1) for tylosin and tetracycline, respectively. The recovery of both tylosin and tetracycline from spiked samples of lake waters, runoff samples, soil saturation extracts, and nanopure water was close to 100%. Tetracycline ELISA was highly specific for tetracycline and chlortetracycline but not for other forms of tetracycline (oxytetracycline, demeclocycline, and doxycycline). Analysis of a few liquid swine manure samples by liquid chromatography-mass spectrometry (LC-MS) showed lower concentrations for chlortetracycline as compared with concentrations obtained using ELISA. However, the concentrations of tylosin from ELISA were comparable with that of LC-MS. The lower concentrations of chlortetracycline obtained by LC-MS in manure samples indicate the presence of other similar or transformed compounds that were detected by ELISA but not determined by LC-MS. These results indicate that both ELISA kits can be useful tools for low-cost screening of tylosin, tetracycline, and chlortetracycline in environmental waters. Furthermore, both ELISA procedures are rapid, portable, and easily adaptable for testing of multiple samples simultaneously.  相似文献   
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