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41.
Intermittent wastewater loading, a characteristic of aquaculture operations, undermines the usefulness of treatment wetlands designed using the steady state assumption. Being biological systems, the treatment variability of such wetlands must also be addressed during the design phase. A simulation-optimization model suitable for modeling intermittent pollutant releases and identifying optimal area and wastewater loading patterns for aquaculture operations is integrated with a decision-analytic framework to determine wetland area and release pattern under uncertainty and risk. Wetland area and release patterns corresponding to different decision making priorities were obtained by applying the minimax, maximax, Hurwicz and minimax regret criteria. The developed methodology provides a convenient framework for aquaculture operators and wetland design engineers to consider trade-off between the wetland size (an indicator of construction and opportunity costs) and wastewater loadings (an indicator of operation costs) during the design process. The results can also be used to characterize the risk-attitudes of the aquaculture operators and identify the worth of additional studies (i.e., pilot tests) given their risk-preferences.  相似文献   
42.
Development of a radioimmunoassay procedure for aflatoxin B1 measurement   总被引:1,自引:0,他引:1  
A radioimmunoassaay (RIA) procedure to measure aflatoxin B(1) (AfB(1)) in agricultural commodities was developed. AfB(1) oxime derivative was synthesized, characterized, and used for preparation of (125)I-labeled AfB(1). Antiaflatoxin B(1) serum was raised in-house using AfB(1)-bovine serum albumin conjugate as immunogen. The assay system was optimized in the range of 0.2-5 ng/mL, using a liquid phase (PEG) as well as a solid phase (coated polystyrene beads) separation system. Inter-assay and intra-assay variations, recovery, and parallelism studies validated the assay. AfB(1) analysis was carried out in nearly 130 samples of different agricultural commodities. The correlation coefficient was determined using commercial ELISA and in-house-developed RIA methods.  相似文献   
43.
In the present investigation, the long-term effect of pulse crop inclusion in the maize-wheat rotation was assessed for the nutrient availability and soil-plant nutrient cycling under different nutrient management practices. Including pulses in the maize-wheat rotation improved soil organic carbon (SOC) and plant available macronutrients being higher in maize-wheat-mungbean rotation. Inclusion of mungbean to maize-wheat rotation enhanced the nitrogen (33.9%), phosphorus (46.4%), potassium (36.3%), and sulphur (55.5%) uptake in maize crop; likewise, alternate-year chickpea inclusion increased the uptake of these nutrients by 18.2, 19.1, 21.7, 32.1%, respectively. Inorganic fertilization maintained the positive annual balance of nitrogen, phosphorus, and zinc. By contrast, the nutrient balance under organic nutrient management was mostly negative. The magnitude of negative balance of potassium and sulphur was higher in inorganic than that of organic nutrient management. The low nutrient supply (particularly nitrogen) in organic fertilization largely inhibited the yield of cereal crops but not that of pulses. In view of this, the inclusion of pulses in the cereal-cereal systems could cause substantial improvement in soil fertility and sustainability in Indo-Gangetic plains. We infer that supply of nutrients like nitrogen and phosphorus in organic, and potassium and sulphur in recommended inorganic fertilization merit special attention.  相似文献   
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