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151.
针对宁夏地区新建的河滨 220 kV 智能变电站中顺序控制功能的特点,按照 Q/GWD 383-2009标准中对智能变电站顺序控制功能的要求,分析比较了变电站顺序控制的实现方式,介绍了河滨220 kV智能变电站顺序控制逻辑及方案,对未来宁夏地区智能变电站顺序控制发展应用提出了建议。分析结果表明:河滨220 kV智能变电站顺序控制方案充分考虑了变电站监控系统的特点,为 220 kV 智能变电站自动化系统功能的实现提供了有力技术保障。  相似文献   
152.
In order to measure groundwater age and design nuclear waste disposal sites, it is important to understand the sorption behavior of tritium on soils. In this study, batch tests were carried out using four soils from China: silty clays from An County and Jiangyou County in Sichuan Province, both of which could be considered candidate sites for Very Low Level Waste disposal; silty sand from Beijing; and loess from Yuci County in Shanxi Province, a typical Chinese loess region. The experimental results indicated that in these soil media, the distribution coefficient of tritium is slightly influenced by adsorption time, water/solid ratio, initial tritium specific activity, pH, and the content of humic and fulvic acids. The average distribution coefficient from all of these influencing factors was about 0.1-0.2 mL/g for the four types of soil samples. This relatively modest sorption of tritium in soils needs to be considered in fate and transport studies of tritium in the environment.  相似文献   
153.
为探索浅水湖泊水动力扰动作用对底泥再悬浮影响的规律,在室内矩形水槽内模拟了各种水动力条件下太湖底泥的起动规律,得到了太湖底泥在3种不同起动标准下的起动流速,通过考察上覆水中悬浮物浓度的变化,建立了底泥沉积物再悬浮通量与水体流速的定量化关系。结果表明:太湖底泥在个别动、少量动、普遍动3种标准下的起动流速分别为15、30和40 cm/s,且底泥沉积物再悬浮通量与流速呈现线性正相关关系,再悬浮通量随流速增大而增大,且相关性较好。将该试验结果应用于太湖的水量水质数学模型中,并和太湖实测资料进行了对比,取得了比较满意的效果。该模拟装置能够在室内可控条件下较好地反映太湖沉积物再悬浮特征,对太湖的富营养化治理具有重要意义。  相似文献   
154.
低碳消费偏好与低碳产品需求分析   总被引:5,自引:0,他引:5  
低碳消费方式是低碳经济的重要环节,本文对低碳消费偏好和低碳产品需求及其影响因素作了理论分析和实证研究.首先对低碳产品的消费偏好进行了分析,低碳产品消费偏好的两个最重要特征是二元价值结构的产品和超越基本价值的消费偏好,在此基础上构建了低碳产品效用函数.然后根据低碳产品效用函数给出了低碳产品的一般需求模式,结合低碳产品置信度变量的引进,构建了一个具体的低碳产品需求函数,并对低碳产品需求函数进行分析,揭示了低碳产品需求的一些基本性质.为了验证低碳消费理论分析的结论,做了低碳产品消费的问卷调查.对问卷调查进行统计分析,结果表明:收入越高,对低碳产品支付的价格就越高;低碳产品的环境价值置信度越高,意愿支付价格就越商;低碳产品碳排放量降低越多,低碳产品需求价格就越高.最后,结合以上分析,从低碳宣传和公益广告、设立低碳产品标准、鼓励低碳产品技术研发角度提出了促进低碳消费发展的政策建议.  相似文献   
155.
如何控制人力成本以使组织降本增效一直是国内学者研究的热点。本文主要对国内近5年人力成本管理的300多篇相关文献从研究领域、研究思路等进行综述和评论,并在此基础之上与国外人力成本管理的文献进行对比分析。研究表明:成本收益法是未来人力成本管理研究的发展趋势。  相似文献   
156.
Taking into account current environmental concerns, the main objective of this work focused a national inventory aiming to estimate the amount of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/PCDF) released in Portugal in 2006. The methodology used was based on the Standardized Toolkit for Identification and Quantification of Dioxins and Furan Releases, developed by UNEP Chemicals, in 2005. The method allows the assessment of the amount of PCDD/PCDF released into the environment along five vectors involving air, water, land, products and residues. Facing some difficulties mainly regarding to the availability of data for some activities known to produce PCDD/PCDF, three scenarios (Sc1 to Sc3) corresponding to lower, central and upper estimates were established. The Sc1 scenario (lower estimate) includes the situations where in case of doubt or scarce information, reduced or none emission values were assumed, Sc2 refers to a central estimate, which is believed to be the most realistic for the Portuguese situation, while Sc3 corresponds to the worst case (upper estimate). The results obtained pointed out that the total amount of PCDD/PCDF emitted in Portugal during the period under analysis was in the range of 51.2-217.9 g TEQ year−1, with the most likely value of 95.2 g TEQ year−1 achieved under the Sc2 scenario. This study also showed that the methodology developed by UNEP Chemicals is a very simple one, and the main difficulty is the availability of data. The main indicators calculated in this study were 8.98 μg TEQ/(year person) by taking into account the total amount of PCDD/PCDF released, and 3.63 μg TEQ/(year person) when only air emissions were considered.  相似文献   
157.
制药废水有机污染物特性分析与处理   总被引:1,自引:0,他引:1  
分析了某制药企业废水生物处理站进出水中有机污染物的相对分子质量分布和气相色谱—质谱图谱,提出了根据废水水质特性有针对性地确定制药废水处理工艺的新思路.实验结果表明:进出水中的有机污染物主要是相对分子质量小于1 000的物质,且主要来源于车间5排放的COD比重大、水量小的工段废水;采用旋转蒸馏预处理法处理车间5废水,可使...  相似文献   
158.
Wang  Jiaqing  Lu  Pei  Su  Wei  Xing  Yi  Li  Rui  Li  Yuran  Zhu  Tingyu  Yue  Huifang  Cui  Yongkang 《Environmental science and pollution research international》2019,26(20):20248-20263

Currently, activated coke is widely used in the removal of multiple pollutants from industrial flue gas. In this paper, a series of novel FexLayOz/AC catalysts was prepared by the incipient wetness impregnation for NH3-SCR denitrification reaction. The introduction of Fe-La bimetal oxides significantly improved the denitrification performance of activated coke at mid-high temperature, and 4% Fe0.3La0.7O1.5/AC exhibited a superior NOx conversion efficiency of 90.1% at 400 °C. The catalysts were further characterized by BET, SEM, XRD, Raman, EPR, XPS, FTIR, NH3-TPD, H2-TPR, et al., whose results showed that the perovskite-type oxide of LaFeO3 and oxygen vacancies were produced on the catalysts’ surfaces during roasting. Fe-La doping enhanced the amount of acid sites (mainly Lewis and other stronger acid sites) and the content of multifarious oxygen species, which were beneficial for NOx removal at mid-high temperature. Moreover, it was investigated that the effect of released CO from activated coke at mid-high temperature on the NOx removal through the lifetime test, in which it was found that a large amount of CO produced by pyrolysis of activated coke could promote the NOx removal, and long-term escaping of CO on the activated coke carrier did not have a significant negative impact on catalytic performance. The results of the TG-IR test showed that volatile matter is released from the activated coke while TG results showed that the weight loss rate of 4% Fe0.3La0.7O1.5/AC only was 0.0015~0.007%/min at 300–400 °C. Hence, 4% Fe0.3La0.7O1.5/AC had excellent thermal stability and denitrification performance to be continuously used at mid-high temperature. Finally, the mechanisms were proposed on the basis of experiments and characterization results.

  相似文献   
159.
采用共沉淀法合成了不同Ce与Ti摩尔比的CePO4-TiO2复合材料,利用XRD、TEM、NH3-TPD和H2-TPR技术对其物理化学性质进行了表征,并对其NH3-SCR活性进行了评价。实验结果表明:随着CePO4含量的增加,催化剂的活性提高;当Ce与Ti的摩尔比为8:2时催化剂的活性最高,230 ℃的NO转化率达到100%,且具有更广的温度窗口,优于纯CePO4。表征结果显示,CePO4与TiO2形成固溶体后,颗粒尺寸较为均匀,强酸位的数量增多,氧化还原性能提升,从而提高了催化剂的SCR反应活性,同时改善了其抗水抗硫性能。  相似文献   
160.
高密度电法在原位修复土壤过程中的监控研究   总被引:1,自引:0,他引:1  
采用高密度电阻率成像法(ERT)对上海市某有机污染场地土壤污染原地修复进行研究,通过持续监测药剂注入前后电阻率的改变来推断药剂和污染物的扩散路径。结果表明,药剂扩散的影响半径介于2 m~4 m之间;其影响深度根据注药点和土壤渗透性差异而有所不同,在16 m处注药的影响深度大于监测深度20 m,ERT技术在监控原位注入修复过程中具有较好的可行性和适用性。  相似文献   
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