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531.
P. Bhattacharyya K. Chakrabarti S. Tripathy A. Chakraborty K. Kim S. H. Kim 《Journal of environmental science and health. Part. B》2013,48(5):593-598
The field study was conducted to evaluate the effect of municipal solid waste compost (MSWC) as a soil amendment on L-asparaginase (LA) and L-glutaminase (LG) activities. Experiments were conducted during the wet seasons of 1997, 1998 and 1999 on rice grown under a submerged condition, at the Agriculture Experimental Farm, Calcutta University at Baruipur, West Bengal, India. The treatments consisted of control, no input; MSWC, at 60 Kg N ha? 1; well-decomposed cow manure (DCM), at 60 Kg N ha? 1; MSWC (30 Kg N ha? 1) + Urea (U) (30 Kg N ha? 1); DCM (30 Kg N ha? 1) + U (30 Kg N ha? 1) and Fertilizer, (at 60:30:30 NPK kg ha? 1) through urea, single superphosphate and muriate of potash respectively). LA and LG activities alone and their ratio with organic-C (ratio index value, RIV), straw and grain yield were higher in DCM than MSWC-treated soils, due to higher amount of biogenic organic materials like water-soluble organic carbon, carbohydrate and mineralizable nitrogen in the former. The studied parameters were higher when urea was integrated with DCM or MSWC, compared to their single applications. The heavy metals in MSWC did not detrimentally influence the above-measured activities of soil. In the event of long term MSWC application, changes in soil quality parameters should be monitored regularly, since heavy metals once entering into soil persist over a long period. 相似文献
532.
Jianbin Guo Renjie Dong Joachim Clemens Wei Wang 《Waste management (New York, N.Y.)》2013,33(11):2219-2224
Many Chinese biogas plants run in the lower range of mesophilic conditions. This study evaluated the performance of a completely stirred anaerobic reactor treating pig manure at different temperatures (20, 28 and 38 °C). The start-up phase of the reactor at 20 °C was very long and extremely poor performance was observed with increasing organic loading rate (OLR). At an OLR of 4.3 g ODM L?1 d?1, methane production at 28 °C was comparable (3% less) with that at 38 °C, but the risk of acidification was high at 28 °C. At low OLR (1.3 g ODM L?1 d?1), the biogas process appeared stable at 28 °C and gave same methane yields as compared to the reactor operating at 38 °C. The estimated sludge yield at 28 °C was 0.065 g VSS g?1 CODremoved, which was higher than that at 38 °C (0.016 g VSS g?1 CODremoved). 相似文献
533.
534.
考察沸石粉投加对活性污泥增殖及脱氨氮动力学的影响,并根据相关结论探讨了不同泥龄(SRT)条件下沸石粉的生物再生情况。结果表明,曝气池中投加沸石粉可明显提高活性污泥的产率系数和衰减系数。与传统活性污泥法相比,投加沸石粉的试验组稳定运行后,污泥产率系数和衰减系数分别提高12.5%和16.7%;当泥龄≤10 d时,出水氨氮去除率提高10%~37%,继续增加泥龄,氨氮去除率提高不明显。通过对比试验结果的关联性分析,认为在低浓度条件下,沸石中铵离子的解吸速率是沸石生物再生的限制步骤,而且再生速率与泥龄呈正相关对应关系。 相似文献
535.
Shimelis G. Setegn Bijan Dargahi Ragahavan Srinivasan Assefa M. Melesse 《Journal of the American Water Resources Association》2010,46(3):514-526
Setegn, Shimelis G., Bijan Dargahi, Ragahavan Srinivasan, and Assefa M. Melesse, 2010. Modeling of Sediment Yield From Anjeni-Gauged Watershed, Ethiopia Using SWAT Model. Journal of the American Water Resources Association (JAWRA) 46(3):514-526. DOI: 10.1111/j.1752-1688.2010.00431.x Abstract: The Soil and Water Assessment Tool (SWAT) was tested for prediction of sediment yield in Anjeni-gauged watershed, Ethiopia. Soil erosion and land degradation is a major problem on the Ethiopian highlands. The objectives of this study were to evaluate the performance and applicability of SWAT model in predicting monthly sediment yield and assess the impacts of subbasin delineation and slope discretization on the prediction of sediment yield. Ten years monthly meteorological, flow and sediment data were used for model calibration and validation. The annual average measured sediment yield was 24.6 tonnes/ha. The annual average simulated sediment yield was 27.8 and 29.5 tones/ha for calibration and validation periods, respectively. The study found that the observed values showed good agreement with the simulated sediment yield with Nash-Sutcliffe efficiency (NSE) = 0.81, percent bias (PBIAS) = 28%, RMSE-observations standard deviation ratio (RSR) = 0.23, and coefficient of determination (R²) = 0.86 for calibration and NSE = 0.79, PBIAS = 30%, RSR = 0.29, and R² = 0.84 for validation periods. The model can be used for further analysis of different management scenarios that could help different stakeholders to plan and implement appropriate soil and water conservation strategies. 相似文献
536.
537.
量子点在环境污染物检测中的应用进展 总被引:1,自引:0,他引:1
作为一类理想的荧光探针,量子点近年来在环境污染物定性定量分析方面的应用取得了很大进展,为环境监测提供了一种新的方法和技术,显示出极大的优越性。综述了量子点分子印迹、量子点自组装膜、双色量子点比率荧光传感等新技术在国内外环境污染物检测方面的研究进展,并对其发展前景作了展望。 相似文献
538.
M. Boulaid A. Tihane R. Oaddi A. Elfanaoui K. Bouabid A. Ihlal 《International Journal of Green Energy》2017,14(14):1182-1191
This paper analyses actual performance of three grid-connected photovoltaic systems based on different silicon technologies, installed at the faculty of sciences of Agadir. The outdoor facilities consist of 2.04 kWp of mono crystalline (m-Si), 1.86 kWp of amorphous (μcSi/a-Si:H), and 2.04 kWp of multi crystalline (mc-Si) silicon PV systems. Datasets were collected during one entire year under real measured irradiation and ambient temperature conditions. The performance of these roof mounted PV systems was conducted on daily and monthly bases. Parameters like annual specific yield, system efficiency, and performance ratio were evaluated and found to be 1827 kWh/kWp.year, 20.9% and 80.2% for amorphous, 1863 kWh/kWp.year, 21.3% and 80.7%, for mono crystalline and 1895 kWh/kWp.year, 21.7% and 82.2% for multi crystalline. 相似文献
539.
Cheng‐Shin Jang Chen‐Wuing Liu Shih‐Kai Chen Wen‐Sheng Lin 《Journal of the American Water Resources Association》2012,48(1):61-73
Jang, Cheng‐Shin, Chen‐Wuing Liu, Shih‐Kai Chen, and Wen‐Sheng Lin, 2011. Using a Mass Balance Model to Evaluate Groundwater Budget of Seawater‐Intruded Island Aquifers. Journal of the American Water Resources Association (JAWRA) 48(1): 61‐73. DOI: 10.1111/j.1752‐1688.2011.00593.x Abstract: The study developed a mass balance model to evaluate the groundwater budget of seawater‐intruded island aquifers using limited available data. The Penghu islands were selected as a study area. As sparse observed data were available in the islands, methods of combining water and chloride balances were used to determine the amounts of groundwater pumping, seawater intrusion, aquifer storages, and safe yields in the shallow and deep aquifers. The groundwater budget shows that seawater intrusion to freshwater aquifers was 1.38 × 106 and 0.29 × 106 m3/year in the shallow and deep aquifers, respectively, indicating that the seawater intrusion is severe in the both aquifers. The safe yield of the shallow aquifer was 14.56 × 106 m3/year in 2005 which was four times higher than that of the deep aquifer (3.70 × 106 m3/year). However, the annual pumping amounts in the shallow and deep aquifers were 4.77 × 106 and 3.63 × 106 m3/year, respectively. Although the safe yield of the shallow aquifer is enough for all water resources demands, only 55% of exploitation amount was extracted from the shallow aquifer due to its poor water quality. Groundwater exploitation in the deep aquifer should be significantly reduced and regulated by a dynamic management of pumping scheme because the annual pumping amounts are close to the safe yield and seawater intrusion occurs continually. Additionally, to alleviate further aquifer salination, at least half of the current annual groundwater abstraction should be reduced. 相似文献
540.
Jafet C.M. Andersson Alexander J.B. Zehnder Bernhard Wehrli Hong Yang 《Journal of the American Water Resources Association》2012,48(3):480-493
Andersson, Jafet C.M., Alexander J.B. Zehnder, Bernhard Wehrli, and Hong Yang, 2012. Improved SWAT Model Performance with Time-Dynamic Voronoi Tessellation of Climatic Input Data in Southern Africa. Journal of the American Water Resources Association (JAWRA) 48(3): 480-493. DOI: 10.1111/j.1752-1688.2011.00627.x Abstract: In this study, we compared two approaches to obtain climatic time series for the Soil and Water Assessment Tool (SWAT), namely the conventional centroid method and time-dynamic Voronoi tessellation, and assessed the performance of SWAT in simulating discharge and smallholder maize yields in Southern Africa. Climatic time series were estimated with each method. The Voronoi method utilized all available precipitation and temperature data, but the centroid method used only 14.5 and 82.5%, respectively. After centroid processing, sub-basin time series were on average 42 and 63% incomplete, respectively. After Voronoi processing, all time series were complete. SWAT was fed with each climate dataset. Each model setup was independently calibrated and validated against discharge and maize yield. Similar model performance was obtained with both methods for yield. The root mean squared error during calibration was 0.26 and 0.27 t ha−1 for the centroid and Voronoi methods, respectively (p-value: 0.80). However, daily discharge simulations improved significantly with the Voronoi method. The coefficient of determination increased from 0.24 to 0.39 in the calibration period (p-value: 9.6 × 10−13) and from 0.41 to 0.48 in the validation period (p-value: 3.1 × 10−3). The Voronoi method improved the simulation of the river flow regime. The largest improvements were obtained in data scarce situations, at high spatial and temporal resolution, and where the centroid method performed the worst. 相似文献