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81.
This study developed an integrated (flow, voltage, and temperature) micro sensor using the micro-electro-mechanical systems (MEMS) technology. It was inserted into the high temperature proton exchange membrane fuel cell (HT-PEMFC) for local real-time measurement. The integrated micro sensor is made of 40 µm thick stainless steel base material, and its protective layer is formed by polyimide (PI) that has better temperature resistance. The integrated micro sensor has three functions, and is favorably characterized by small size, good acid resistance and temperature resistance, quick response, real-time measurement, and being able to be put in any place for measurement. After calibration, and its reliability confirmed, the integrated micro sensor is inserted into the HT-PEMFC for local microcosmic measurement.  相似文献   
82.
环境保护督察巡视:党政同责的顶层制度   总被引:2,自引:2,他引:0       下载免费PDF全文
环境保护督察巡视是党政同责的核心制度安排。本文从环保督察巡视与党政同责的关系与实践出发,认为该制度是从决策源头监督,既有法律依据,也有政策要求,其他部门的督察以及环保考核、约谈等实践为环保督察巡视积累了经验。从环保督察巡视制度的内涵与特征来看,该制度有明确的行动指南、统一的党政同责督察体系、较高的督察组权威、明确的巡视重点与突破方向等特点。最后,本文从理顺环境目标责任制度、制定督察实施细则、提升督察巡视权威性、开展第三方评估与社会监督等方面提出了政策建议。  相似文献   
83.
本研究以环境水文地球化学理论为基础并采用数理统计的方法,对研究区地下水样和土样的分析数据进行了处理。通过浸滤模拟试验、红外光谱和差热分析等实验手段,对京杭大运河(杭州段)两侧浅层地下水中铁、锰含量偏高的成因进行了探讨。结果表明,该区地下水中铁、锰主要来自含水粘性土层,本区还原的介质环境及特有的地质条件对铁、锰含量偏高有直接影响。  相似文献   
84.
Sampling and analysis of ambient dioxins in northern Taiwan   总被引:2,自引:0,他引:2  
Chang MB  Weng YM  Lee TY  Chen YW  Chang SH  Chi KH 《Chemosphere》2003,51(10):1103-1110
In this study, ambient air samples were taken concurrently in the vicinity area of a large-scale municipal waste incinerator (MWI) and the background area for measuring polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) concentrations from November 1999 through July 2000 in northern Taiwan. The results obtained from eighteen ambient air samples indicate that the mean PCDD/F concentration of seventeen 2,3,7,8-substituted congeners in wintertime (188–348 fg-I-TEQ/m3) is significantly higher than that measured in summertime (56–166 fg-I-TEQ/m3). In addition, the seasonal PCDD/F concentrations are compared with the ambient air quality data including CO, NO2, PM10 and TSP sampled from Taipei area to gain better insights. It indicates that the variation of ambient air PCDD/F concentrations is closely correlated with that of PM10 concentrations. Besides, the results indicate that the I-TEQ concentration of ambient air in sampling site B (directly downwind of the MWI) is of the highest while the sampling site A (upwind of MWI) is of the lowest among all sampling sites. This implies that existing MWI can be a significant emitter of PCDD/Fs in this area. Furthermore, the patterns of the PCDD/F congener distribution at all sampling sites (including the background site in Taoyuan) are quite similar. OCDD concentration is of the highest among seventeen PCDD/F congeners investigated and accounts for about 35% of the total concentration. As for the I-TEQ concentrations, 2,3,4,7,8-PeCDF is the most significant contributor, generally being responsible for 30–45% of the total I-TEQ values depending on the sampling sites and seasons.  相似文献   
85.
整地施肥试验结果表明,全垦、带垦和穴垦三种整地方式以及施肥对尾叶按造林成活率和保存率均无明显的影响,成活率在95%-98.8%之间,保存率在92.1%-97.7%之间.整地能改变土壤性状,如土壤孔隙度全垦为57.88%。穴垦为49.42%;对林木生长有促进作用,但作用效果很快减少,如造林3年后的林木材积全垦、带垦分别为穴垦的136.4%和120.0%,5年后却分别下降到116.5%和108.3%.施肥可提高土壤养分,促进林木生长.造林5年后的调查结果,穴垦施肥林地的土壤有机质、速效N分别为15.447g/kg和49.230mg/kg,林木年均树高生长为1.25m;不施肥处理的有机质、速效N分别为10.388g/kg和35.715mg/kg,林木年平均生长量为0.35m;林木材积施肥处理的为不施肥的9.8倍.整地施肥还可提高林木叶片的养分含量.  相似文献   
86.
IntroductionCopper,leadandzinchavesimilar geochemical propertiesandundergrowthcloselyinenvironmentalnaturalbodiesbecausetheycommonlyhavethestrongeraffinitywithsulphur.PeoplehaveknownthatCuandZnareessentialelementsandPbisdeleteriousforhumanbody .Peoplear…  相似文献   
87.
IntroductionThevolatileorganiccompounds (VOCs)isoneofthefivemajorprimarygasouspollutants(particulates,SOx ,NOx ,VOCs,CO) ,inwhich 31VOCspollutantsincludingbenzene,acroleinandaliphatic ,aromatichalogenatedhydrocarbonsarelistedinall 1 2 9prioritypollutantsbytheEnv…  相似文献   
88.
沉积物粒度对重金属吸附的影响   总被引:2,自引:0,他引:2  
本文报道了渭河沉积物对重金属的吸附特性.结果表明,渭河沉积物吸附重金属的粒度效应决定于不同粒度沉积物的物质构成和颗粒表面特性,该效应是由沉积物对重金属的吸附速率的差别来体现的.不同粒度所决定的颗粒比表面积的差异不是影响重金属吸附粒度效应的主要因素.  相似文献   
89.
A generic methodology for determining the required surface area of a final clarifier is presented. Clarification and thickening requirements are integrated to form a unified procedure for final clarifier design. The new method is based on results obtained by Yuen (2002) on the solids flux theory for a secondary clarifier; it does not require the specification of recycle rate, which is computed as an output of the method. The author shows that there is a minimum required surface area (A(m)) for a final clarifier under the thickening requirement when the designed recycle rate is set at the maximum allowable value (FR)m (at the critical state). The designed surface area and the return activated sludge pumping capacity can be determined by applying a safety factor to A(m) and (FR)m, respectively. The method is shown to conform to conventional design criteria under typical design conditions.  相似文献   
90.
活性炭纤维在机动车尾气净化中的研究与应用展望   总被引:4,自引:0,他引:4  
机动车尾气净化控制的一个难点在于冷启动阶段,此时由于温度较低,催化剂尚未完全起作用,导致排出的污染物浓度较高。阐述了活性炭纤维的基本特性,特别是其低温吸附与催化性能对NO和CO的转化作用,讨论了活性炭纤维作为机动车尾气净化材料所需的改性及方法,并展望了其应用前景。  相似文献   
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