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11.
上海降水中氢氧同位素特征及与ENSO的关系   总被引:8,自引:4,他引:4  
基于收集2014年8月至2015年8月上海70个降水样品,分析上海降水同位素特征与温度、降水量的相关关系,分析不同时间尺度下降水中δ~(18)O、氘盈余与ENSO事件的联系.结果表明上海地区大气降水中δD与δ~(18)O冬春较高,夏秋较低.上海大气降水线方程截距和斜率比全球降水线方程偏小,可能是因为降水过程中受到不平衡的二次蒸发.在不同的时间尺度下,上海地区降水中δ~(18)O与气温和降水量具有不同的相关关系,冬季存在着较弱的温度效应,而全年呈现出较显著的降水量效应,受大气环流过程影响明显.取样期间,降水中δ~(18)O与d值(过量氘)清晰记录了La Ni1a向El Ni1o之间的过渡,拉尼娜期间,降水中δ~(18)O与d值偏负;El Ni1o期间,δ~(18)O与d值偏正.  相似文献   
12.
中试研究了内循环(IC)反应器处理甲醇制烯烃(MTO)废水的启动和运行过程,同时考察了颗粒污泥的性状及沼气产量的变化情况。试验过程运行稳定,系统抗冲击性强。以絮状污泥为接种污泥,经过131 d的启动和运行,IC反应器的COD去除负荷可达10 kg/(m~3·d)以上,COD去除率可达90%以上。IC反应器中的成熟颗粒污泥形状规则、密实、粒径大、沉降速率快。IC反应器的沼气产量符合理论预期。  相似文献   
13.
采用新型膜蒸馏技术对水中As(III)与As(Ⅴ)的去除展开了研究。实验结果表明,膜蒸馏对水中As (III)及As (Ⅴ)具有较高的去除能力:当产水中砷含量超过10 μg/L时,原水中As (III)与As (Ⅴ)的浓度可分别高达40 mg/L和2 000 mg/L。局部润湿现象的存在导致As (III)及As (Ⅴ)跨膜至产水侧,PVDF微孔膜在溶液中的负电性以及As (III)与 As (Ⅴ)在溶液中存在形式的不同导致膜蒸馏对两者去除能力的差异。360 h连续运行过程中产水通量及电导率稳定,且整个过程中As (III)均低于检测限,说明PVDF微孔膜具有良好的疏水性和稳定的除砷性能。  相似文献   
14.
Phthalate esters (PAEs) were examined in indoor and outdoor dust samples from the subtropical city of Guangzhou, China. The ∑(16)PAEs concentrations ranged from 121 to 3,223 μg g(-1) dust, with the median concentration of 840 μg g(-1) dust. Significantly higher concentrations of PAEs in dust samples were found in offices where electrical and electronic devices, carpet pads, and office furniture were widely used. Of the 16 PAEs, diisobutyl phthalate (DiBP), di-n-butyl phthalate (DnBP), and di(2-ethylhexyl) phthalate (DEHP) dominated the PAEs in indoor and outdoor dust samples, and accounted for >96.8% and >93.1% of the ∑(16)PAEs concentrations, respectively. The median daily inhalation exposure of ∑(16)PAEs were 3.53 and 0.247 μg kg(-1) body weight day(-1), and at the 95(th) percentile were 7.62 and 0.530 μg kg(-1) body weight day(-1), up on the measured concentrations and estimated dust ingestion rates, respectively, for toddles and adults. The ubiquitous distribution of PAEs as noted in this study suggests the need for detailed assessment of PAEs concentrations using more sites and to further investigate the factors influencing PAEs exposure in China.  相似文献   
15.
我国现实之患是旱涝沙,潜在之忧是水土气污染。这里水是指江河湖海和地下水,土是土壤,气为大气。水土气是养育人类的基本环境要素。即使是人类需要的生存环境,也得不到应有的珍惜和保护,这是人类的最大悲哀。960万平方公里陆地和300多万平方公里海洋足以让我国人民活得潇洒自在,健康快  相似文献   
16.
汉江蜀河水电站属于Ⅱ等大(2)型水电站,水库的建成、运行可能对岸坡的稳定性造成一定的影响,尤其是水库蓄水后的库水位变化及与库水位变化相关的参数,对岸坡的稳定影响极大,因此弄清楚库水位变化与其相关的参数对岸坡稳定性的影响,是汉江蜀河水电站成功运营必须解决的问题之一。以地质背景为基础,结合具体坡段的岩性、结构特征等,从水库水位公式的建立,到在不同库水位的条件下,运用数值模拟对岸坡稳定性系数和相关参数的变化进行了分析评价。  相似文献   
17.
18.
稠油热采系统综合能耗监测方法及评价   总被引:1,自引:1,他引:0  
栾海波 《油气田环境保护》2012,22(6):44-46,88,89
针对目前稠油热采系统节能措施和节能产品对某一环节单个节能产品的节能效果进行检测、评价的现状,提出了将稠油热采系统作为一个整体,采取组合节能措施及产品,给出了稠油热采系统的能耗监测流程、监测要求、程序与方法、数据分析评价方法等。形成了稠油热采系统综合能耗监测数据分析及效果评价方法。  相似文献   
19.
Li X  Lin L  Luan T  Yang L  Lan C 《Chemosphere》2008,70(10):1903-1909
Environmental contaminants with estrogenic activity have recently attracted attention due to their potential detrimental effects on the reproduction of human and wildlife. The aim of this study was to evaluate the use of endogenous glutathione and glutathione-related enzymes as biomarkers of exposure to landfill leachate effluent and bisphenol A (BPA) in the freshwater snail, Bellamya purificata. Following exposure to 1%, 5% and 10% landfill leachate effluent and 1, 10, 50 and 100mugl(-1) BPA for 0, 2, 7 and 15d, activities of glutathione S-transferase (GST), selenium-dependent glutathione peroxidase (SeGPx) and glutathione reductase (GR) and levels of total glutathione were measured in the gills and digestive glands of the snails. GST and total glutathione were the most sensitive parameters in both exposure scenarios. GST activities increased by about 80%, while total glutathione decreased to 70% and 80% in the gills and digestive glands, respectively. In contrast, SeGPx and GR activities remained at the same levels in all the treatment groups compared with those of controls. The results indicated that among glutathione and glutathione-related enzymes, GST activity and total glutathione level, which showed dose-dependent dynamics, could be used as biomarkers of aquatic ecosystems contaminated with landfill leachate.  相似文献   
20.
ZnBiYO4 was synthesized by a solid-state reaction method for the first time. The structural and photocatalytic properties of ZnBiYO4 were characterized by X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy and UV-Vis diffuse reflectance. ZnBiYO4 crystallized with a tetragonal spinel structure with space group I41/A. The lattice parameters for ZnBiYO4 were a = b = 11.176479 Å and c= 10.014323 Å. The band gap of ZnBiYO4 was estimated to be 1.58 eV. The photocatalytic activity of ZnBiYO4 was assessed by photodegradation of methyl orange under visible light irradiation. The results showed that ZnBiYO4 had higher catalytic activity compared with N-doped TiO2 under the same experimental conditions using visible light irradiation. The photocatalytic degradation of methyl orange with ZnBiYO4 or N-doped TiO2 as catalyst followed first-order reaction kinetics, and the first-order rate constant was 0.01575 and 0.00416 min-1 for ZnBiYO4 and N-doped TiO2, respectively. After visible light irradiation for 220 min with ZnBiYO4 as catalyst, complete removal and mineralization of methyl orange were observed. The reduction of total organic carbon, formation of inorganic products, SO42- and NO3-, and evolution of CO2 revealed the continuous mineralization of methyl orange during the photocatalytic process. The intermediate products were identified using liquid chromatography- mass spectrometry. The ZnBiYO4/(visible light) photocatalysis system was found to be suitable for textile industry wastewater treatment and could be used to solve other environmental chemical pollution problems.  相似文献   
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