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101.
同时以活性炭纤维(ACF)为阳极和阴极,在隔膜电解槽中研究了不同电流密度下蒽醌染料活性艳蓝KN-R的电化学脱色.考察了ACF阳极和ACF阴极各自对染料的脱色性能.结果表明,当电流密度为1.0~1.5 mA/cm2时,电解槽中发生阳极电氧化和阴极电还原同时进行的成对电解脱色.在ACF电极上,活性艳蓝KN-R的电氧化脱色比电还原脱色容易进行,1.0 mA/cm2时,阴阳两极室脱色率分别为69%和93%,而1.5 mA/cm2时,阳极室脱色率保持在93%,阴极室脱色率达到79%.  相似文献   
102.
Kim KB  Seo KW  Kim YJ  Park M  Park CW  Kim PY  Kim JI  Lee SH 《Chemosphere》2003,50(9):1167-1173
In this study, we tested phenolic compounds such as bisphenol A (BPA), 4-nonylphenol (NP), 4-octylphenol (OP) and 4-propylphenol (PP) by using glucose-6-phosphate dehydrogenase (G6PD) in estrogen sensitive human breast cancer cells (MCF-7 cells) and glutathione peroxidase (GPx) in female immature Sprague-Dawley (SD) rats. This study was designed to investigate whether phenolic compounds have estrogenic effects in these useful screening methods for endocrine disruptors. We chose 6 h as the incubation period for the G6PD assay through a preliminary experiment using 17beta-estradiol (E2). Above the concentration of 1 x 10(-8) M, BPA significantly increased the G6PD activity in a concentration-dependent manner, relative to the control. NP (over the concentration of 1 x 10(-9) M) also enhanced the G6PD activity by about 1.8 times that of the control. OP produced weaker effects on G6PD than NP, and showed a tendency to increase the G6PD activity. PP did not affect the G6PD activity. These results show that BPA and NP have the effect of enhancing G6PD activities in MCF-7 cells. In the in vivo GPx assay, both BPA and E2 significantly increased the uterus wet weights and dramatically enhanced uterine GPx activities in immature female rats in a dose-dependent manner. Treatment with NP (500 mg/kg/day) increased significantly both the uterine GPx activity and the uterus wet weights in immature female rats. OP (500 mg/kg/day) also caused a significant increase in uterine GPx activity, but had no effect on the uterus wet weights. This finding indicates that the change in uterine GPx activities could be a more sensitive parameter than that of uterus wet weights in immature rats. This study implies that phenolic compounds have a weak estrogenic effects.  相似文献   
103.
中国-喜马拉雅柴胡属的花粉形态及其系统学意义   总被引:1,自引:0,他引:1  
本文报道了中国-喜马拉雅柴胡属(BupleurumL.)24种,7变种,2变型的花粉形态研究结果,全部在光学显微镜和扫描电镜下作了比较观察。有关柴胡属花粉形态的研究,除大苞柴胡(B.euphorbioidesNakai)和红柴胡(B,scorzonerifoliumWilld.)外.其余均为首次报道,根据该属花粉粒的形态和萌发孔特征,其花粉形态可分为三个类型,即:近菱形角孔类型、矩形边孔类型及其二者之间的过渡类型。花粉形态资料支持德国植物系统学家德鲁特(O,Drude,1898)关于柴胡属的系统位置,将其隶于芹亚科(Apioideae),芹族(Apieae),葛缕子亚族(Carinae)。  相似文献   
104.
介绍了华阳发电有限责任公司综合污水治理工艺,并对其处理效果和经济效益进行分析,为同类污水的处理提供了工程实例。  相似文献   
105.
黄河三角洲地区总体开发战略研究   总被引:1,自引:2,他引:1  
本文通过对黄河三角洲地区资源与经济状况的调查分析,从区域整体及其外部环境相互关系角度分析了黄河三角洲地区的战略地位、战略优势与问题、战略方向和战略措施,试图从理论和实践上为本区大规模开发建设提供科学依据。  相似文献   
106.
浦宝康 《交通环保》1999,20(2):36-38
介绍ISM制订的背景,其目的是要加强执行有关海上安全、海洋防污染和海员培训等国际公约。ISM的内容也作了简要说明。香港明华船务公司请中国船级社协助以实施ISM规则。该文较为详细地介绍了制订各种规章制度和文件,以及在公司和船上落实ISM的措施。经过两年努力,终于取得符合ISM的证书,但是要完全达到ISM的要求,仍有许多工作要做。  相似文献   
107.
PM_(2.5) aerosol samples were collected over 12 hr and 24 hr intervals in an inland background area, Gongga Mountain National Nature Reserve(hereafter shortened to Gongga), during the summer of 2011. Polar organic tracers, inorganic ions and meteorological data were measured. The purpose of this work was to investigate the variation patterns, formation and sources of the secondary organic aerosol tracers in the studied atmosphere. The average concentrations of isoprene oxidation products, α-pinene oxidation products, β-caryophyllinic acid, sugars, sugar alcohols and anhydrosugars were 88.6 ± 106.1, 3.6 ± 5.7,0.13 ± 0.30, 13.6 ± 13.1, 31.9 ± 31.4 and 14.8 ± 10.7 ng/m3 respectively in all aerosol samples.The aged α-pinene second organic aerosol(SOA) tracers(i.e., 3-hydroxyglutraric acid(3 HGA), 3-hydroxy-2,2-dimethylglutaric acid(HDMGA), 3-acetylpentandioic acid(APDA) and 3-methyl-1,2,3-butanetricarboxylic acid(MBTCA)) correlated significantly with each other in the 24 hr PM2.5 aerosol samples, indicating that OH· is the major factor controlling the formation of these α-pinene SOA tracers. Using the positive matrix factorization(PMF) model and the tracer-based source apportionment method, we calculated that isoprene oxidation products, α-pinene oxidation products, sesquiterpene oxidation products, biomass burning, fungi spores and anthropogenic SOA accounted for 21.9% ± 5.5%, 8.4% ± 2.1%, 3.0% ± 0.7%, 5.2% ± 5.3%, 5.0% ± 6.2% and 31.4% ± 7.8% of organic carbon respectively during the sampling period.  相似文献   
108.
为了探索光盘的热解试验,利用TG/DTG和DSC技术对废旧光盘的热解特性和热值进行试验研究。由废弃光盘得出的曲线与PC曲线相似,说明光盘的主成分为聚碳酸酯,聚碳酸酯的着火点低、燃尽温度高、燃烧热值高。废旧光盘中含有聚碳酸酯,可以将其作为钢铁冶金或者火力发电等高能耗生产中的固体燃料。这样既减少废旧光盘造成的固体污染,也使资源得到充分利用。由实验获得废旧光盘的热分解开始温度为460℃终止温度870℃,热值达到-19 258 J/g。  相似文献   
109.
This research aimed at determining the variation of reservoir fluid property during the high-pressure air injection process. For this purpose, the forward multiple contact experiment was employed by pressure–volume–temperature (PVT) system to investigate the physical property variation of the crude oil and the complex oxidation reactions. The results show: under the relative low temperature and pressure condition, instead of carbon dioxide, carbon monoxide dominates the products in the air phase. The gas/oil ratio and volume ratio increased due to the generated gas while the viscosity and density achieved a descending trend. The colloid and bitumen in the oil phase reduced by half but the amount of wax achieved a small increase. The low-temperature oxidation and pyrolysis reactions caused the fluctuated change of the different compounds. The amount of light compounds decreased at the beginning and then increased while that of heavy compounds showed the opposite trend. But at last, due to the H/C ratio, the light compounds increased to more than their initial value.  相似文献   
110.
Li X  Li Y  Zhang Q  Wang P  Yang H  Jiang G  Wei F 《Chemosphere》2011,84(7):957-963
The concern about emissions of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs) from steel industrial parks has increased in the past decades. In this study, polyurethane foam (PUF)-disk based passive air samples were collected in and around a big steel industrial park of Anshan, Northeast China from June 2008 to March 2009. The levels, seasonal variations and potential sources of PCDD/Fs, PCBs and PBDEs in the atmosphere around the steel industrial complex were investigated, and potential contribution of these three groups of persistent organic pollutants (POPs) from iron and steel production was also assessed. The air concentrations of ∑17PCDD/Fs (summer: 0.02-2.77 pg m−3; winter: 0.20-9.79 pg m−3), ∑19PCBs (summer: 23.5-155.8 pg m−3; winter: 14.6-81.3 pg m−3) and ∑13PBDEs (summer: 2.91-10.7 pg m−3; winter: 1.10-3.89 pg m−3) in this targeted industrial park were relatively low in comparison to other studies, which implied that the industrial activities of iron and steel had not resulted in serious contamination to the ambient air in this area. On the whole, the air concentrations of PCDD/Fs in winter were higher than those of summer, whereas the concentrations of PCBs and PBDEs showed opposite trends. The result from principal component analysis indicated that coal combustion might be the main contributor of PCDD/F sources in this area.  相似文献   
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