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751.
752.
引导企业节能的政策选择模型研究 总被引:2,自引:0,他引:2
作为经济主体的企业既是能源和资源的主要消耗者。又是环境污染的主要排放源。因此。有利于节约能源、减少污染的企业节能成为实现社会、经济和生态可持续发展的根本途径。然而,我国企业节能管理和节能市场处于初级阶段。企业节能工作进展缓慢,企业的节能成本远远大于所能获得的收益,因此缺乏主动节能动力,如何选择并建立有效引导企业节能的政策模式成为政府亟待解决的问题。为此。结合现有节能政策。在政府与企业之间进行完全信息动态博弈分析,然后,依据当前企业整体的节能管理状态以及节能市场的发展程度。构建出有效引导企业节能的政策选择模型.进而为政府制定行之有效的节能政策提供理论依据和具体建议,以推动中国节能战略的实施,促进节能目标的实现。 相似文献
753.
以人均相对灾害救济强度为指标,利用EOF方法分析了1978~1994年我国农村救灾款发放的时空分异规律,发现其5种主要空间分布形式;在东部地区,1984年以前华北救灾强度较东北和江南相对偏大,以后则相反。 相似文献
754.
755.
设计了一种基于GSM的机车监控系统。用无线电手机传输监控装置产生的原始数据至PC机 ,来达到实时监控机车运行状况的目的。实践表明 ,该系统简单灵活 ,传输可靠 ,具有良好的稳定性和可靠性。与现行车载监控装置相比 ,新型机车监控系统具有提高数据的实时性、减轻工作人员的劳动强度等优点 相似文献
756.
Long-Term Effects of Fertilization on Soil Organic Carbon Changes in Continuous Corn of Northeast China: RothC Model Simulations 总被引:4,自引:0,他引:4
Soil organic C (SOC) content can increase by managing land use practices in which the rates of organic C input exceed those of organic C mineralization. Understanding the changes in SOC content of Black soils (mainly Typic Halpudoll) in northeast China is necessary for sustainable using of soil resources there. We used the RothC model to estimate SOC levels of Black soils under monoculture cropping corn in a long-term fertilization trial at Gongzhuling, Jilin Province, China. The model outputs for the changes in SOC were compared with measured data in this long-term fertilization/manure trial. The sound performance of model in simulating SOC changes suggests that RothC is feasible with Black soils in the temperate climatic region of northeast China. The modeled and measured results indicated that the treatment without fertilizer/farmyard manure (FYM) addition led to a continuous decline in SOC during the study period and N and NPK fertilization were inadequate to maintain the SOC levels in the plow layer (upper 20 cm) unless FYM was added under the current conventional management associated with no above-ground crop residues returning into the soil. Soil organic carbon could follow the same path of decline if the same management practices are maintained. Model results indicate that returning above-ground crop residues to the soil from 2002 to 2022 would increase SOC by 26% for the treatment without fertilization addition, 40% for N treatment, 45% for NPK treatment, and 38% and 46% for N and NPK treatments with FYM addition, compared to the levels in the corresponding treatments in 2002. The simulation results suggest that the RothC model is a feasible tool to assess SOC trend under different management practices, and returning above-ground crop residues into the soil would lead to a remarkable increase in SOC of Black soils in the region. 相似文献
757.
The oxidation capability of horseradish peroxidase (HRP) and hydrogen peroxide (H2O2) coupled oxidation of aromatic hydrocarbons (o-xylene-d10 and naphthalene-d8) was investigated. Batch experiments were conducted using horseradish peroxidase prepared in potassium phosphate buffer in the presence of H2O2. The oxidation of aromatic hydrocarbon was tested as a function of HRP at a fixed concentration of H2O2, and as a function of the concentration of H2O2 at a constant HRP activity (4000 units/ml). The mass removal of o-xylene-d10 and naphthalene-ds increased with increasing HRP enzymatic activity, and up to 54% and 51% of mass removal were observed for o-xylene-d10 and naphthalene-d8, respectively. Increasing the concentration of H2O2 resulted in increased mass removal of aromatic hydrocarbons. 相似文献
758.
The US Army Engineering Research Development Center (ERDC) uses a modified form of the Revised Universal Soil Loss Equation
(RUSLE) to estimate spatially explicit rates of soil erosion by water across military training facilities. One modification
involves the RUSLE support practice factor (P factor), which is used to account for the effect of disturbance by human activities
on erosion rates. Since disturbance from off-road military vehicular traffic moving through complex landscapes varies spatially,
a spatially explicit nonlinear regression model (disturbance model) is used to predict the distribution of P factor values
across a training facility. This research analyzes the uncertainty in this model's disturbance predictions for the Fort Hood
training facility in order to determine both the spatial distribution of prediction uncertainty and the contribution of different
error sources to that uncertainty. This analysis shows that a three-category vegetation map used by the disturbance model
was the greatest source of prediction uncertainty, especially for the map categories shrub and tree. In areas mapped as grass,
modeling error (uncertainty associated with the model parameter estimates) was the largest uncertainty source. These results
indicate that the use of a high-quality vegetation map that is periodically updated to reflect current vegetation distributions,
would produce the greatest reductions in disturbance prediction uncertainty. 相似文献
759.
方力 《辽宁城乡环境科技》2006,26(1):15-17
利用ADMS-城市扩散模型和鞍山市2002年排放清单数据库,建立了鞍山市SO2(二氧化硫)空气扩散模型.同时利用2002年的气象和监测资料对模型进行了验证。结果表明:年和四季的SO2监测值和预测值的一致性较好。 相似文献
760.
通过分析90年代以来,上海城市化学危险品陆上运输规律,确定了10条重点路段和二个重点渡口,并对其进行了灾祸评价,提出了上海城市化学危险品陆上运输安全对策. 相似文献