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331.
Environmental Science and Pollution Research - Water conservation and soil retention are two essential regulating services that are closely related, and their relationship might produce synergies...  相似文献   
332.
To characterize Streptomyces isolated from cattle feces for converting lignocellulose into reducing sugars, five Streptomyces strains were screened. All the strains could convert lignocellulose into reducing sugars. The strain A16 accumulate 3.3-folds more reducing sugars on cottonseed shells treated with ethanol than without the treatment (P?<?0.05). The five strains did not accumulate more reducing sugars on rice straws and wheat brans than those on cottonseed shells. Compared with A10 alone, the microbial combination of F1 + A10 accumulated 19, 61, and 25 % less reducing sugars on cottonseed shell, rice straw, and wheat bran than those by A10 solely, respectively (P?<?0.05). Further studies indicated that the activities of avicelase and xylanase were not correlated with the reducing sugar amount accumulated by the test strains. Strain A7 could produce more cellular lipids with xylose and glucose as the sole carbon sources. This study shows the potential for Streptomyces strains from herbivore feces to convert lignocelluloses into lipids and reducing sugars for fuel production.  相似文献   
333.

The content of fine sand (< 200 μm) in primary sludge is relatively high in Chongqing sewage treatment plant owing to the part of rainwater will be mixed with sand and discharged into the municipal pipe network. Due to the insufficient separation of the sand, different obstacles to subsequent treatment processes may increase equipment wear, reduce effective volume of the tank, or shorten the cleaning cycle. There is a common use of grit chamber for the separation. Nevertheless, the use of hydrocyclone shows an outstanding performance in cost effectiveness and ease operation. The primary sludge in a sewage plant in Chongqing was monitored, and the average concentration of total suspend solids (TSS), total sand content, and volatile suspended solid (VSS) were 40.25 g/L, 17.51 g/L, and 13.41 g/L, respectively. The size of sand in the sludge was small, and the sand below 30 μm accounted for about 70% of the total sand. It formed flocs with organic matter and was removed in subsequent process units. While the size between 30–200 μm, called fine sand, was the main separation object, accounted for about 28.5%. According to XRF and XRD analysis, the sludge composition was mainly composed of quartz (SiO2), plagioclase (Na(AlSi3O8)), and calcite (CaCO3), which were similar to the main mineral composition of surface sediments and mountain rocks in the main urban area of Chongqing. A single-factor experiment on two types (FX100 and FX50) of hydrocylones was conducted to determine their abilities concerning the separation of fine sand and enrichment of organic matters from primary sludge. FX100 and FX50 showed best performance in the case of P = 0.17 Mpa, underflow diameter (Du) = 18 mm and P = 0.20 Mpa, Du = 6 mm, respectively. The removal efficiency of fine sand by hydrocyclone FX50 was 71.39%. While, it had poor performance on organic matter enrichment and the removal efficiency of which was 17.38%. By contrast, the removal rate by FX100 reached 61.89% for fine sand and only 6.89% for organic matters detached. The superimposition effect did not appear in the serial experiments on hydrocylone FX100 and FX50, but the power is 3.5 times of that of single-stage hydrocylone FX100. Comprehensive consideration of the processing capacity per unit time and operating power, the hydrocylone FX100 was more suitable for actual operation.

  相似文献   
334.
Environmental Science and Pollution Research - The regeneration of EDTA-FeII is a key step in electrobiofilm reduction-integrated systems for NOx removal from industrial boiler flue gas. The...  相似文献   
335.
In this paper, we construct a multi-stage coordinated programming model under tax system to control SO2 emission. The model is based on an explicitly formulated SO2 abatement cost function created under Chinese condition. Analysis of the effectiveness and impact on the economy of the model is carried out with consideration of game theory. By solving the model, theoretical results show that the volume-based multi-stage SO2 tax system has two properties: effectiveness and equal-rate. Based on these theoretical results, empirical study is also performed using Chinese historical data. Compared with yearly single-stage programming model, the tax rate generated by the coordinated multi-stage programming model is time-invariant and rather moderate in scale. The total abatement cost among planning years in our model is 21.03 % less than the actual number and 6.68 % less than that in the single-stage situation. The tax payment suggested by our model is 10.62 % less than by the single-stage model. In general, a coordinated multi-stage programming model helps reduce the overall costs of environmental protection while achieving the same emission control target with less burden added to the economy.  相似文献   
336.
Environmental Science and Pollution Research - The accurate prediction of daily reference crop evapotranspiration (ETO) enables effective management decision-making for agricultural water...  相似文献   
337.
Environmental Science and Pollution Research - More and more emphasis is placed on the common development of economy and ecological environment in China’s development strategy, and one of the...  相似文献   
338.
339.
本文针对国内多数单位在器件筛选过程中老炼试验样品种类杂,批次多,试验过程记录的数据量大的现状,利用虚拟仪器软件编程,通过IBM服务器终端作为上位机与多台老炼电源通信,从而对多批老炼试验进行网络控制和实时监测,并分析老炼过程中采集到的电学参数判断老炼试验的状态,自动采取相应的故障处理措施,实现了紧急中断试验、快速保护试验样品,提供试验异常时的电参数波动数据的功能,具有很强的实用性。  相似文献   
340.
Environmental Science and Pollution Research - Soil conditioners can be used to compensate for the insufficient soil nutrition and organic matter (OM) of arable soils. However, the traditional...  相似文献   
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