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31.
ABSTRACT: A test of the suitability of subsurface drip irrigation (SDI) for alfalfa (Medicago sativa L) compared to a sprinkler, was conducted on a Kansas producer's field where the soil is loam. The treatments included drip tape spacing of 60, 40, and 30 inches placed at depths of 18 and 12 inches. A nearby plot irrigated by a center pivot sprinkler was seeded to alfalfa and used for comparison. Seedling emergence and yield were adversely affected at 60 inch spacing, while the depth of placement of drip tapes (18 and 12 inches) showed no effect on yield. The site served for education and allowed comparison between SDI tape spacing and center pivot system.  相似文献   
32.
Environment, Development and Sustainability - The present study evaluated the effectiveness of stocking the Gangetic carps, viz. Labeo catla, Labeo rohita, and Cirrhinus mrigala, in a large...  相似文献   
33.
Environment, Development and Sustainability - Banking industries are blamed to be among the major factors that affect global climate change both directly and indirectly. The green banking concept...  相似文献   
34.
The tropical deciduous forest in Bangladesh provides a substantial part of country’s forest and where the government has introduced participatory agroforestry landuse. This study examined management issues, financial viability, and environmental as well as social sustainability of this landuse system. The forest department allocated a plot of size 1.0 ha among the selected participants where they were allowed to practice agriculture as well as to plant tree species for 10 years. The financial indicators indicated that the landuse system was profitable and attractive [net present value (NPV) = US$ 17,710 and benefit-cost ratio (BCR) = 4.12]. It was also viable and suitable from the social and environmental stand points. The study concluded that under the present environmental and socio-economic scenario, this production system could be the best management tool that would earn money, stop forest degradation, and finally be a model of sustainable land management in an overpopulated country.  相似文献   
35.
Surma River is polluted day by day by human activities, poor structured sewerage and drainage system, discharging industrial and household wastes. The charas (natural channels) are responsible for surface runoff conveyance from its urban catchments to the receiving Surma River. Water samples have been collected from a part of Surma River along different points and analyzed for various water quality parameters during dry and monsoon periods. Effects of industrial wastes, municipal sewage, and agricultural runoff on river water quality have been investigated. The study was conducted within the Chattak to Sunamganj portion of Surma River, which is significant due to the presence of two major industries – a paper mill and a cement factory. The other significant feature is the conveyors that travel from India to Chattak. The river was found to be highly turbid in the monsoon season. But BOD and fecal coliform concentration was found higher in the dry season. The water was found slightly acidic. The mean values of parameters were Conductivity 84–805 μs; DO: dry-5.52 mg/l, monsoon-5.72 mg/l; BOD: dry-1mg/l, monsoon-0.878 mg/l; Total Solid: dry-149.4 mg/l, monsoon-145.7 mg/l. In this study, an effort has been taken to investigate the status of concentration of phosphate (PO−4) and ammonia–nitrogen (NH4–N) at four entrance points of Malnichara to the city, Guali chara, Gaviar khal and Bolramer khal. Data has been collected from March–April and September–October of 2004. Concentrations have been measured using UV Spectrophotometer. Although the phosphate concentration has been found within the limit set by DOE for fishing, irrigation and recreational purposes, however ammonia–nitrogen has been found to exceed the limit.  相似文献   
36.
Cellulase production was carried out by solid state bioconversion (SSB) method using rice straw, a lignocellulosic material and agricultural waste, as the substrate of three Trichoderma spp. and Phanerochaete chrysosporium in lab-scale experiments. The results were compared to select the best fungi among them for the production of cellulase. Phanerochaete chrysosporium was found to be the best among these species of fungi, which produced the highest cellulase enzyme of 1.43 IU/mL of filter paper activity (FPase) and 2.40 IU/mL of carboxymethylcellulose activity (CMCase). The “glucosamine” and “reducing sugar” parameters were observed to evaluate the growth and substrate utilization in the experiments. In the case of Phanerochaete Chrysosporium, the highest glucosamine concentration was 1.60 g/L and a high concentration of the release of reducing sugar was measured as 2.58 g/L obtained on the 4th day of fermentation. The pH values were also recorded. The range of the pH was about 5.15 to 5.56 in the case of Phanerochaete Chrysosporium.  相似文献   
37.
The select chemical and engineering characteristics of biosolids produced at a wastewater treatment plant in Eastern Australia were investigated to assess its suitability as structural fill material in road embankments. Results of comprehensive set of geotechnical experimentation including compaction, consolidation, creep, hydraulic conductivity and shear strength tests implied that biosolids demonstrate behavior similar to highly organic clays with a higher potential for consolidation and settlement. Results of chemical study including heavy metals, dichloro diphenyl trichloroethane (and derivatives) and organochlorine pesticides, indicate that biosolids samples are within the acceptable limits which allows their usage under certain guidelines. Results of tests on pathogens (bacteria, viruses or parasites) also indicated that biosolids were within the safe acceptable limits. Technical and management suggestions have been provided to minimize the possible environmental risks of using biosolids in road embankment fills.  相似文献   
38.
In this study, we have developed urethane modified polyesteramide (UPEA) resin by the condensation polymerization reaction of N,N-bis (2-hydroxy ethyl) jatropha oil fatty amide (HEJA) and itaconic acid to form polyesteramide (PEA). The latter was further reacted with different percentages (16–22%) of toluylene 2,4-diisocyanate (TDI) to prepare UPEA. The structural elucidation of HEJA, PEA, UPEA was carried out by FT-IR, 1H-NMR and 13C-NMR spectroscopic techniques. The coating was made on mild steel strips. The physico-chemical and physico-mechanical analyses were carried out by standard laboratory methods. The thermal stability of polymer was studied by thermogravimetric analysis. Thermal analyses shows that these coatings can be used safely up to 230 °C. The corrosion protective behavior of UPEA coatings was investigated in acid, alkali, water and xylene. All the coatings exhibited good chemical resistance performance in acid, alkali, saline and organic solvents, while the resin UPEA 20 showed the best performance.  相似文献   
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40.
Fansidar is a fixed combination of two antimalarial agents a diaminopyrimidine (Pyrimethamine) and a sulphonamide (Sulphadoxine) in the ratio 1:20- that have been used extensively worldwide for the treatment of Chloroquine resistant Plasmodium falciparum malaria, toxoplasmosis and Pneumocystis carinii pneumonia in patients with the acquired immunodeficiency syndrome. This study examined the effect of Fansidar on chromosomes in human lymphocyte culture. Fansidar was added to peripheral blood lymphocyte cultures in vitro at four different concentrations: 5,15, 25 and 50 microl in the ratio 1:20, 3:60, 5:100 and 10:200 microg ml(-1). Result shows that this drug induces moderate increase in the frequency of gaps, breaks and rearrangements. Therefore it can be concluded that Fansidar has moderate clastogenic effect on human chromosomes in vitro.  相似文献   
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