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681.
The present study outlines applications of an enzyme-linked immunosorbent assay (ELISA) for the analysis of clenbuterol residues. Antisera were raised from rabbits immunized with diazotized clenbuterol-bovine serum albumin (BSA) conjugate. The assay was specific to clenbuterol with a half-maximum inhibition concentration (IC(50)) of 1.8 ng/mL and 2.5 ng/mL in blank swine urine and phosphate buffer solution, respectively. The assay had high cross-reactivity (86%) with mabuterol, but low with other adrenergic agonists and antagonists. The average recovery of clenbuterol, as measured with the ELISA, ranged from 90% to 112% in swine urine samples and from 86% to 95% in feeds, respectively. This new assay was compared with commercial ELISA test kits. An excellent correlation (r(2) = 0.98) between the two methods and satisfactory recoveries suggest that the new assay can be suitable for the determination of clenbuterol residues in real samples. The assay was used to analyze clenbuterol residues in 103 swine urine samples and 68 feed samples collected from northern China. Approximately 50% of the urine samples and 25% of the feed samples analyzed were found positive (concentration of clenbuterol > or = 1 ppb). The results indicate that clenbuterol was misused in some of the areas surveyed.  相似文献   
682.
黄土高原绿色建筑体系评价指标体系   总被引:1,自引:0,他引:1  
阐述了绿色建筑体系是可持续发展的人类住区,介绍了可持续发展人类住区和可持续发展评价指标体系国内外研究状况,提出了建立绿色建筑体系评价指标体系的原则,提出了黄土高原县,乡,镇层次上的绿色建筑体系评价指标体系框架,以及指标量化的方法。  相似文献   
683.
生物陶粒柱—PAC—膜过滤装置系统处理饮用水实验研究   总被引:2,自引:0,他引:2  
生物陶粒柱和粉末活性炭作为淹没式中空纤维膜过滤装置的预处理工艺不仅解决了膜过滤装置氨氮去除不利的弱点,避免了亚硝酸盐氮的积累,而且在浊度、细菌、有机物等方面极大地降低了膜过滤装置的负荷。生物陶粒柱-PAC-膜过滤装置系统高锰酸盐指数平均去除率为76.97%,氨氮和亚硝酸盐氮的平均去除率分别达到顾95.50%和99.15%。  相似文献   
684.
The purpose of this study was to determine and evaluate the spatial changes in soil salinity by using geostatistical methods. The study focused on the suburb area of Beijing, where urban development led to water shortage and accelerated wastewater reuse to farm irrigation for more than 30 years. The data were then processed by GIS using three different interpolation techniques of ordinary kriging (OK), disjunctive kriging (DK), and universal kriging (UK). The normality test and overall trend analysis were applied for each interpolation technique to select the best fitted model for soil parameters. Results showed that OK was suitable for soil sodium adsorption ratio (SAR) and Na+ interpolation; UK was suitable for soil Cl? and pH; DK was suitable for soil Ca2+. The nugget-to-sill ratio was applied to evaluate the effects of structural and stochastic factors. The maps showed that the areas of non-saline soil and slight salinity soil accounted for 6.39 and 93.61 %, respectively. The spatial distribution and accumulation of soil salt were significantly affected by the irrigation probabilities and drainage situation under long-term wastewater irrigation.  相似文献   
685.
Severe perfluoroalkyl acid (PFAA) contamination resulting from the fast-growing semiconductor, electrochemical, and optoelectronic industries has been determined in the river water in the vicinity of the Taipei area, Taiwan, during recent years. However, little is known about body burdens of the PFAA contaminations in local residents, especially children living in the Taipei area recently. In this study, ten target PFAA analytes consisted of three perfluorosulfonates (PFSAs) and seven perfluorocarboxylates (PFCAs) in the blood serum samples, collected from 225 healthy children with an average age of 13.6 years in the Taipei area from 2009 to 2010, were analyzed via high-performance liquid chromatography–tandem mass spectrometry (HPLC–MS/MS). As the dominant PFAA contaminant in the blood serum samples from Taiwanese children, perfluorooctane sulfonate (PFOS) contributed 86 % of all the target PFAA analytes, while the other nine analytes contributed less than 5 % individually. PFOS showed the highest median up to 29 ng/mL, ranging from 0.03 to 148 ng/mL, which was higher than that observed in the serum samples collected from Taiwanese children between 2006 and 2008. Statistically, serum concentrations of perfluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHxS), and perfluorooctanoic acid (PFOA) had significantly positive correlations with ages of children (p?<?0.05). Furthermore, serum PFBS, PFHxS, and PFOA concentrations in the male children were considerably higher than those in the female children (p?=?0.049, p?=?0.000, p?=?0.000).  相似文献   
686.
将耐盐脱氮复合菌剂投加到序批式生物反应器中,构建生物强化高盐废水处理系统(SBR1),以未投加复合菌剂系统(SBR2)作为对照,分析典型周期中氮素和溶解氧的变化趋势以及盐度冲击对脱氮效果的影响.实验表明,在曝气时间为6h时,生物强化系统脱氮率可稳定在96%以上,出水总氮浓度为3.8 mg/L左右.反应中始终无硝氮、亚硝氮积累,生物强化系统具有同步硝化好氧反硝化能力.当受到5%和7%较高盐度冲击时,生物强化系统表现出优于对照系统的抗盐度冲击能力,能够快速恢复原有活性,且出水总氮低于15 mg/L;当受到0%盐度的淡水冲击时,对照系统中耐盐污泥失活且无法恢复,而生物强化系统只需投加少量(3%)耐盐脱氮复合菌剂,即可快速恢复活性,出水总氮低于15 mg/L.本研究能够为生物强化高盐废水脱氮系统的构建和运行提供技术支持.  相似文献   
687.
Fumonisin B1 (FB1) is a secondary metabolite produced by Fusarium verticillioides or Fusarium proliferatum, which present in food and feed. It causes hazardous effects on human and animal health. A monoclonal antibody (mAb) against FB1 was produced and a simple, reliable and sensitive, competitive, indirect enzyme-linked immunosorbent assay (ci-ELISA) for detection of FB1 was developed and the experiment conditions were optimized. The coating concentration of FB1-ovalbumin (FB1-OVA) was 500 ng mL?1, the action concentrations of anti-FB1 mAb and goat anti-mouse IgG were 1.28 × 104 and 1:5000, respectively. The 50% inhibitory concentration (IC50) was 11 ng mL?1, with a detectable range of 1.25–250 ng mL?1, and a limit of determination (LOD) of 1.15 ng mL?1. The cross-reactivity (CR) of the antibody against fumonisin B2 (FB2) was 60.4, and <1% against deoxynivalenol (DON), aflatoxin B1 (AFB1), ochratoxin A (OTA) or zearalenone (ZEN). In spiked samples (250 ng g?1, 500 ng g?1, 1000 ng g?1), the mean recoveries ranged from 86.7 ± 5% to 102 ± 4%, and the coefficient of variation (CV) ranged from 3% to 10%. A survey of 96 corn samples from Bozhou, Fuyang, Bengbu, and Hefei, in Anhui province, China, was performed. Frequencies of FB1 contamination were 83.3%, 95.8%, 20.8% and 91.7%, and the mean concentrations of positive samples were 0.702 μg kg?1, 0.883 μg kg?1, 0.074 μg kg?1, and 0.276 μg kg?1, respectively. The results of this study suggest that the ci-ELISA developed in this study can be used to identify FB1 in corn, furthermore, further study is needed to investigate FB1 contamination in food and feed to prevent its harmful health effects.  相似文献   
688.
采用原位阳极氧化法制备二氧化钛纳米管阵列(TNAs)光电极,并采用电沉积工艺对其进行石墨烯修饰。以罗丹明B(Rh.B)为目标污染物,考察了染料溶液中主要无机离子对光电极光催化降解Rh.B的影响。实验结果表明,150W氙灯照射1 h,石墨烯/TNAs对Rh.B光催化降解率达到75%,是TNAs光电极的1.45倍。溶液中NO-3,Ca2+和Mg2+促进光电极对Rh.B的光催化降解,而SO2-4,Cl-和F-则会抑制对Rh.B的降解。  相似文献   
689.
分别采用水解酸化与好氧(SBR)、厌氧(UASB)与好氧(SBR)工艺对涤纶短纤维废水的生物降解性能进行研究。水解酸化与好氧工艺在进水COD为1 900 mg/L的时候,去除率在80%左右。采用UASB-SBR工艺,进水COD为2700 mg/L时,COD去除率可以达到96%,出水COD〈100 mg/L。实验研究表明,涤纶短纤维废水更适合采用UASB-SBR工艺来处理,并且能够取得较好的效果。  相似文献   
690.
基于MapInfo的矿山通风安全信息系统开发   总被引:1,自引:0,他引:1  
根据现代矿山通风系统对人机交互的要求,利用OLE技术和VisualBasic编程语言,对MapInfo进行二次开发,形成了矿山通风安全信息系统。所开发的系统集成了MapInfo强大的地图、信息、数据库等的管理功能,实现了电子地图与数据库的自动连接和双向查询,完成了信息的可视化管理,并可与生产监控、调度系统集成,用于指导煤矿安全生产,防止重大事故发生。该系统具有修改通风图、生成通风管理报表、备份数据等功能,同时还可以对通风系统中的防瓦斯突出、防尘、防火、安全管理、风机等日常管理数据进行处理,在实际应用中取得了良好的效果。  相似文献   
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