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941.
陈飞星 《中国人口.资源与环境》2000,(3)
本文在“良性发展论 :可持续发展超越与丰富”一文基础上 ,对良性发展的五大战略目标的指代及相互关系进行了讨论 ,并对其一一作了图解分析。 相似文献
942.
在水资源短缺条件下,垦区农业发展采取了多种经营,发展以棉花、水果和养鹿为主的高效特色农业,同时加强工程建设,进行水资源开源节流,强化管理和对绿洲的保护,这些已成为维持绿洲稳定和促进绿洲农业经济发展的关键措施。 相似文献
943.
944.
通过对我区废水处理设施运转情况的调查分析,得出废水处理设施运转效率低是由于设计水平低,施工质量差,设备管理不善及领导不重视等原因所致。 相似文献
945.
Arman Shehabi Arpad Horvath William Tschudi Ashok J. Gadgil William W Nazaroff 《Atmospheric environment (Oxford, England : 1994)》2008,42(24):5978-5990
Cooling buildings with large airflow rates of outside air when temperatures are favorable is an established energy-saving measure. In data centers, this strategy is not widely used, owing to concerns that it would cause increased indoor levels of particles of outdoor origin, which could damage electronic equipment. However, environmental conditions typical of data centers and the associated potential for equipment failure are not well characterized. This study presents the first published measurements of particle concentrations in operating data centers. Indoor and outdoor particle measurements were taken at eight different sites in northern California for particulate matter 0.3–5.0 μm in diameter. One of the data centers has an energy-efficient design that employs outside air for cooling, while the rest use conventional cooling methods. Ratios of measured particle concentrations in the conventional data centers to the corresponding outside concentrations were significantly lower than those typically found in office or residential buildings. Estimates using a material-balance model match well with empirical results, indicating that the dominant particle sources and losses have been identified. Measurements taken at the more energy-efficient site show nearly an order of magnitude increase in particle concentration when ventilation rates were high. The model indicates that this increase may be even higher when including particles smaller than the monitoring-equipment size limitation. Even with the increases, the measured particle concentrations are still below concentration limits recommended in industry standards. 相似文献
946.
The removal of Polycyclic Aromatic Hydrocarbons in the wastewater treatment process: experimental calculations and model predictions 总被引:3,自引:0,他引:3
The removal of PAHs during the wastewater treatment process was examined in an activated sludge mode conventional facility. Concentrations reported are taken from an earlier measuring campaign. Removals of PAHs ranged between 28 and 67% in the primary, <1-61% in the secondary stage, and 37-89% in the whole process. Significant positive relationships were observed for removal efficiencies and the log K(ow) of PAHs in the primary and the log K(H) of PAHs in the secondary stage. Experimental removals were compared to those obtained from the FATE model. In the primary stage, predicted removals were lower than those experimentally calculated while in the secondary stage were higher. Predicted removals were apportioned mainly to sorption with negligible contribution from volatilization and biodegradation. Remarkable consistency between experimental and modeled removal efficiencies (-20-+20%) was observed for almost all PAHs in the whole treatment process. 相似文献
947.
948.
实验研究了不同操作条件、板片型式及板间距对除雾器除雾效率及压降的影响规律,并采用计算流体力学(CFD)方法对除雾器内流场进行了数值模拟与分析。研究结果表明,操作条件对压降和流场影响较小,而板片型式特别是迎风面的几何结构是影响流场与压降的关键因素;随着气速的增大,除雾效率增高,但当气速增到某一临界值(4~5 m/s)后,除雾效率随着气速的增大而迅速减小;除雾器压降的数值模拟结果与实验值吻合良好;除雾器内存在2个回流区,回流区是产生除雾器临界气速的重要原因之一。研究结果可为除雾器优化设计提供指导。 相似文献
949.
等离子体协同金属氧化物催化氧化苯的研究 总被引:1,自引:0,他引:1
以Al2O3和Ag/Al2O3为催化剂,采用介质阻挡放电(DBD)反应器降解空气中低浓度的苯(C6H6),重点考察了苯的转化率、能量效率随能量密度的变化关系.研究发现:苯的氧化产物为一氧化碳(CO)和二氧化碳(CO2),当能量密度为94 J/L时,在催化剂Ag/Al2O3、Al2O3存在以及不使用催化剂的条件下,苯的能量效率分别达到了0.054 mol/kW·h、0.038 mol/kw·h与0.024 mol/kW·h.同时,探讨了国外应用低温等离子体技术处理气体污染物的相关研究成果,并与本研究做了比较. 相似文献
950.