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981.
通过对典型商贸市场的实地调研,依据历年商贸市场火灾事故统计数据,采用将统计方法与专家评分相结合的方法,运用系统安全及模糊数学的相关理论,提出了商贸市场火灾风险评估方法,从而为商贸市场的安全管理及火灾风险评价提供了切实可行的参考依据。  相似文献   
982.
据最新研究表明.用户的满意程度和企业的盈利能力与产品和服务的质量紧密相关。较高的产品质量和服务质量,能使用户满意,同时也能维持较高的价格。因此,质量改进方案通常会增加企业的盈利能力。  相似文献   
983.
Abstract: Thermoelectric power generation is responsible for the largest annual volume of water withdrawals in the United States although it is only a distant third after irrigation and industrial sectors in consumptive use. The substantial water withdrawals by thermoelectric power plants can have significant impacts on local surface and ground water sources, especially in arid regions. However, there are few studies of the determinants of water use in thermoelectric generation. Analysis of thermoelectric water use data in existing steam thermoelectric power plants shows that there is wide variability in unitary thermoelectric water use (in cubic decimeters per 1 kWh) within and among different types of cooling systems. Multiple‐regression models of unit thermoelectric water use were developed to identify significant determinants of unit thermoelectric water use. The high variability of unit usage rates indicates that there is a significant potential for water conservation in existing thermoelectric power plants.  相似文献   
984.
对乌鲁木齐市燃煤点派数量、耗煤量、污染物的排放量以及在各功能区的分布分别进行了统计分析,对污染物的排放量在不同高度空间的分布也进行了统计分析,从而得出了确切的结论并提出了相应的建议。  相似文献   
985.
Contamination of oxygen-consuming organics (OCOs) was one of the most serious problems in the Yellow River of China. This study was conducted to analyze monitoring of the data on OCOs contamination for the river in 1980 and during 1992–1999 as well as examining the effect of suspended solids (SS) on chemical oxygen demand (CODMn) and biochemical oxygen demand (BOD5) of river water. Several significant results have arisen from the study. First, CODMn and BOD5 of the river water showed an increasing trend from the upper to the lower reaches of the mainstream. BOD5 values of river water in 1992 were significantly higher than those in 1980 and showed an increasing trend during 1992–1999. Second, OCOs in river water of the mainstream was attributed mainly to point sources; the ratio of point to non-point sources of BOD5 was about 2.81. The load from point sources showed an increasing trend during 1992–1998. In contrast, the load from non-point sources manifested a decreasing trend during this period; this was caused by the decreasing trend of SS content in river water. The total load of BOD5 from point and non-point sources displayed an increasing trend during 1992–1998. Third, as the humic substances in SS can hardly be biologically oxidized in natural conditions but can be oxidized by chemical oxidants such as potassium permanganate, CODMn was not suitable for being regarded as a parameter reflecting the pollution degree of OCOs in river water with a high SS content.  相似文献   
986.
Environmental Science and Pollution Research - In this work, a series of polyethyleneimine (PEI) impregnated metal-organic framework (UiO-66) with varying PEI loadings were prepared and applied as...  相似文献   
987.
运用大数据技术,对硫黄回收装置的工艺运行参数数据及SO_2排放数据进行挖掘与分析,提取与SO_2排放浓度强相关的关键性操作变量,完成硫黄回收装置环保大数据建模,从而实现硫黄回收装置SO_2排放浓度的预测和预警,并自动生成当前工况下硫黄回收装置尾气SO_2达标优化方案。  相似文献   
988.
我国安全生产的形势和任务   总被引:10,自引:0,他引:10  
论述了我国安全生产工作发展概况与安全的关系 ,分析了我国安全生产状况 ;指出了我国安全生产面临的主要难点 ;提出了我国安全生产工作的重任所在 ;笔者认为 ,只要从实际出发 ,坚持改革、标本兼治和技术创新 ,发挥政府、企业、劳动者三方协调机制的作用 ,借鉴和吸收国际成功经验 ,我国安全生产水平是会列于世界先进行列的。  相似文献   
989.
For biofilters treating waste gases containing volatile organic compounds(VOCs), biomass accumulation is a common problem which will induce bed clogging and significant decrease in VOCs removal efficiency during long-term operation. In this study, ozone injection was developed as a biomass control strategy, and its effects on the biofilter performance and the microbial community structure were investigated in long-term operation. Two biofilters,identified as BF1 and BF2, were operated continuously for 160 days treating gaseous toluene under the same conditions, except that 200 mg/m3 ozone was continuously injected into BF1 during days 45–160. During the operation period, ozone injection did not change the toluene removal efficiency, while the pressure drop of BF1 with ozone injection was significantly lowered compared with BF2. The wet biomass accumulation rate of BF1 was 11 g/m~3/hr, which was only46% of that in BF2. According to the carbon balance result, ozone injection also increased the toluene mineralization rate from 83% to 91%, which could be an important reason for the low biomass accumulation. The PMA-q PCR result indicated that ozone injection increased the microbial viability of the biofilm. The high-throughput sequencing result also revealed that the dominant phyla and genera were not changed significantly by ozone injection, but some ozonetolerant genera such as Rhodanobacter, Dokdonella and Rhodococcus were enhanced by ozone exposure. All the results verified that ozone injection is capable of sustaining the long-term performance of biofilters by lowering the biomass accumulation, increasing the microbial viability and changing the microbial community structure.  相似文献   
990.
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