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141.
基于ASP.NET的安全信息管理系统 总被引:1,自引:0,他引:1
安全信息管理系统主要包括对安全信息数据的收集、存储、加工处理、传递和利用等功能.本文主要阐述了B/S结构的特点,以及一种全新的Web开发技术ASP.NET在安全信息管理系统中的应用.这使在Web上对安全信息数据进行增、删、改、查操作成为可能,对防止事故发生,减少由事故造成的损失,提高企业的安全管理水平等具有重要的现实意义. 相似文献
142.
水产品中甲氰菊酯残留的ELISA快速检测 总被引:3,自引:0,他引:3
为快速检测水产品中甲氰菊酯的残留,应用水溶性碳化二亚胺(EDC)法将甲氰菊酸与牛血清白蛋白(BSA)和卵清蛋白(OVA)偶联,合成了甲氰菊酯的人工免疫抗原和包被抗原.免疫抗原经紫外扫描和聚丙烯酰胺电泳验证构建成功,用此抗原免疫试验兔子,获得了甲氰菊酯的多克隆抗体.经检测,抗体对甲氰菊酯具有较好的特异性和灵敏性.在此基础上建立了水产品中甲氰菊酯残留的间接ELISA检测法.理想的甲氰菊酯-OVA包被抗原质量浓度为1.6 mg/L,酶标二抗(羊抗兔IgG-HRP)的稀释度为1∶1000,多抗的稀释度为1∶3 200,最适检测范围为20~200 μg/kg,在实际样品检测时的最低检出限为20 μg/kg,接近或达到气相色谱法的测定水平,但检测速度大大提高,可在3 h内完成近百个样品的分析,适合甲氰菊酯的快速检测. 相似文献
143.
土壤中多环芳烃的SPMD辅助解吸行为研究 总被引:2,自引:0,他引:2
为了开发一种表征土壤中憎水性有机污染物解吸及生物有效性的新方法,建立了半透膜被动采样装置(SPMD)研究土壤中有机污染物解吸行为的方法,利用SPMD分析了多环芳烃菲、芘和苯并[a]芘在3种不同性质土壤中的辅助解吸行为.结果表明,SPMD是一种很好地表征土壤中憎水性有机污染物解吸及生物有效性的手段. SPMD辅助解吸多环芳烃的效率与土壤有机质及多环芳烃性质有关.随着土壤有机质含量的降低,土壤中菲和芘的SPMD解吸率逐渐升高,对于10 mg/kg染毒水平,当土壤有机质含量由18.68%降低到0.3%时,2种化合物的解吸率分别由56.45%和48.28%上升到接近100%;但是对于苯并[a]芘,粘土表现出明显的滞留能力,在有机质含量(0.3%)很低、粘土含量(39.05%)较高的3号土壤中,苯并[a]芘的解吸率仅有66.97%.不同多环芳烃SPMD辅助解吸率差别很大,随着土壤有机质含量的降低,以及污染物浓度的提高,菲和芘的解吸差异逐渐缩小,而苯并[a]芘与上述2种多环芳烃的差异很大,主要是由于苯并[a]芘具有高度亲脂性,并且分子较大,造成其容易滞留在粘土的微孔及有机质的致密结构中. 相似文献
144.
Kinetics of enzymatic unhairing by protease in leather industry 总被引:2,自引:0,他引:2
In leather industry, unhairing is a heavy pollution operation. The conventional lime-sulfide process produces a large amount of sulfide which is toxic to health and difficult to dispose. Moreover, conventional lime-sulfide process leads to the destruction of the hair causing increased COD, BOD and TDS loads in the effluent. As an alternative method, enzymatic unhairing is a promising clean technology. The main utilized enzyme preparations are proteases.There are many reports about enzymatic unhairing, most of which are qualitative. The kinetics of enzymatic unhairing by protease was discussed in this article. It will provide useful information to enzymatic unhairing. In our research, by analysis of the concentrations of released total protein in enzyme bath during protease unhairing, the good linearity between released total protein and square root of time (min1/2) was obtained at the initial stage. The good linearity suggests that enzymatic unhairing by protease is a diffusion-controlled process at the initial stage. The analysis of kinetics of released saccharides also confirms the same conclusion. On the other hand, the same characteristics between the kinetics of released saccharides and that of released total protein further confirms that it is the hydrolysis of core protein by protease that leads to the degradation of proteoglycans and the release of protein and saccharides. However, in our tests, the kinetics of released collagen indicates that the injury to skin took place in 3-6 h. Therefore, it’s necessary to control the time of protease unhairing within an appropriate limit. 相似文献
145.
Chemical forms of Zn, Ni, Cu, and Pb in municipal sewage sludge were investigated by adding humus soil to sludge and by
performing sequential extraction procedures. In the final sludge mixtures, Zn and Ni were mainly found in Fe/Mn oxide-bound (F3) and
organic matter/sulfide-bound (F4) forms. For Zn, exchangeable (F1), carbonate-bound (F2), and F3 forms were transformed to F4 and
residual forms (F5). For Ni, F1 and F2 forms were transformed to F1, F2, and F3 forms. Both Cu and Pb were strongly associated with
the stable forms F4 and F5. For Cu, F2 and F3 forms were major contributors, while for Pb, F3 and F4 forms were major contributors to
F5. Humus soil dosage and pH conditions in the sludge were strongly correlated with the forms of heavy metals. Five forms were used
to evaluate metal mobilities in the initial and final sludge mixtures. The mobilities of the four heavy metals studied decreased after 28
days. The metal mobilities in the final sludge mixtures were ranked in the following order: Ni > Zn > Cu = Pb. Leaching tests showed
that the mobilities of Zn and Ni in lower pH conditions (pH 4) were higher than those in higher pH conditions (pH 8). 相似文献
146.
147.
餐厨垃圾国家政策及地方法规研究和思考 总被引:1,自引:0,他引:1
文章介绍了餐厨垃圾的产生和危害,以及目前国家及地方在餐厨垃圾处理方面颁布和制定的指导性文件、政策性法规、及行业标准。通过总结苏州、宁波、西宁、乌鲁木齐等城市在治理餐厨垃圾过程中的经验,结合这些地区在餐厨垃圾处理方面的地方法规、收集运输系统、无害化处理体系的建立过程,通过分析思考,提出了适用于一般城市的关于餐厨垃圾收集、运输、处理过程系统性的工作框架。指出了餐厨垃圾处理目前面临的主要问题,并对未来如何推进和完善餐厨垃圾处理工作提出了合理化建议,对政府未来的决策具有一定程度的参考意义。 相似文献
148.
为了解决高温高盐矿井水对碳钢管道和设备腐蚀问题,进行了缓蚀挂片试验,研究适应该类水质的缓蚀剂种类和最佳投加量。试验结果表明:软化剂氢氧化钙和碳酸钠对碳钢均有一定缓蚀效果.其平均缓蚀率分别为17.33%、57.46%。因此药剂软化过程同时达到防腐效果有限:单独投加缓蚀剂HEDP的缓蚀效果明显,其静态缓蚀率82.46%以上,动态缓蚀率76.45%:复合配方缓蚀剂的缓蚀效果最好,最佳配方为“有机膦酸一聚环氧琥珀酸一锌盐”或“有机膦酸一磺酸基团多元共聚物一锌盐”,在投加量80mg/L时动态缓蚀率接近90%。 相似文献
149.
Harish Venkatakrishnan Youming Tan Maszenan bin Abdul Maji Santosh Pathak Antonius Yudi Sendjaj Dongzhe Li Jerry Jian Lin Liu Yan Zhou Wun Jern Ng 《环境科学学报(英文版)》2014,26(4):875-884
A high strength chemical industry wastewater was assessed for its impact on anaerobic microbial com- munity dynamics and consequently mesophilic methane generation. Cumulative methane production was 251 mL/g total chemical oxygen demand removed at standard temperature and pressure at the end of 30 days experimental period with a highest recorded methane percentage of 80.6% of total biogas volume. Volatile fatty acids (VFAs) analysis revealed that acetic acid was the major intermediate VFAs produced with propionic acid accumulating over the experimental period. Quantitative analysis of microbial communities in the test and control groups with quantitative real time polymerase chain reaction highlighted that in the test group, Eubacteria (96.3%) was dominant in comparison with methanogens (3.7%). The latter were dominated by Methanomicrobiales and Methanobacteriales while in test groups increased over the experimental period, reaching a maximum on day 30. Denaturing gradient gel electrophoresis profile was performed, targeting the 16S rRNA gene of Eubacteria and Archaea, with the DNA samples extracted at 3 different time points from the test groups. A phylogenetic tree was constructed for the sequences using the neighborhood joining method. The analysis revealed that the presence of organisms resembling Syntrophomonadaceae could have contributed to increased production of acetic and propionic acid intermediates while decrease of organisms resembling Pelotomaculum sp. could have most likely contributed to accumulation of propionic acid. This study suggested that the degradation of organic components within the high strength industrial wastewater is closely linked with the activity of certain niche microbial communities within eubacteria and methanogens. 相似文献
150.
Perinereis aibuhitensis was used to assess adverse biological effects caused by acute and chronic Pb2+exposure in artificial seawater under controlled laboratory conditions. In 96-hr acute toxicity experiments,the morphological changes showed a positive time/dose-dependent tendency,and the 96-hr LC50 value of Pb2+was 686.41 mg/L. The responses of enzymatic and non-enzymatic antioxidants in tissues including catalase(CAT),peroxidase(POD),superoxide dismutase(SOD),glutathione peroxidase(GSH-PX),malondialdehyde(MDA) and the content of total soluble protein(TSP),were investigated on days 1,4,7 and 10 after Pb2+exposure under chronic toxicity testing. Results showed that the activation of the antioxidant system in P. aibuhitensis depended on the Pb2+concentration and the duration of exposure time.Specifically,POD and SOD activities were induced on the first day of the exposure and decreased to the control level on day 10 after exposure. Therefore,these two indexes could be used to indicate oxidative stress associated with P. aibuhitensis exposure to Pb2+. 相似文献