春季南黄海溶解有机碳的分布特征及其受控因素

依据2007年4月对南黄海调查所得的溶解有机碳(DOC)数据,初步分析了南黄海DOC的分布特征及其影响因素。结果表明,2007年春季南黄海DOC的质量浓度为0.91～2.69 mg/L,平均值为1.62 mg/L,北部近岸DOC浓度高,长江口北部海域及南黄海中部外海DOC含量较低;在垂直方向上,10 m层DOC含量略高,各水层量值相差不大。DOC的分布趋势主要受控于水文结构,某些河口海域,生物生产对DOC含量也有一定的贡献。     

Soil selenium concentration and Kashin-Beck disease prevalence in Tibet, China

In order to investigate the correlation between the prevalence of Kashin-Back disease (KBD) and Se concentrations, natural soil samples and cultivated soil samples were collected from southeastern Tibet, China; and the soil Se concentrations were measured by atomic fluorescent spectrophotometer. It was found that the mean Se concentrations of natural soil samples in KBD areas, from the first layer to the third layer, were 0.17 mg/kg, 0.11 mg/kg, and 0.10 mg/kg, respectively, and in nondisease areas were 0.21 mg/kg, 0.24 mg/kg, and 0.13mg/kg, respectively. The mean Se concentrations of cultivated soil samples were 0.10 mg/kg in KBD areas and 0.23 mg/kg in non-disease areas, respectively. Soil Se concentrations in KBD areas were lower than that in non-disease areas, and the mean concentrations of soil Se in Tibet were lower than the average of China (0.29 mg/kg). Therefore, there is a close relationship between soil Se concentrations and KBD in Tibet. More studies should be concentrated on the impacts of Se deficiency in soils and its relationship with Se concentrations in food-grain and the human body in Tibet areas.     

A mini-microbial fuel cell for voltage testing of exoelectrogenic bacteria

Current methods for testing the electricity generation capacity of isolates are time- and labor-consuming. This paper presents a rapid voltage testing system of exoelectrogenic bacteria called Quickscreen, which is based on a microliter microbial fuel cell (MFC). Geobacter sulfurreducens and Shewanella baltica were used as the model exoelectrogenic bacteria; Escherichia coli that cannot generate electricity was used as a negative control. It was found that the electricity generation capacity of the isolates could be determined within about five hours by using Quickscreen, and that its time was relatively rapid compared with the time needed by using larger MFCs. A parallel, stable, and low background voltage was achieved using titanium as a current collector in the blank run. The external resistance had little impact on the blank run during the initial period. The cathode with a five-hole configuration, used to hydrate the carbon cathode, gave higher cathode potential than that with a one-hole configuration. Steady discharge and current interrupt methods showed that the anode mostly contributed to the large internal resistance of the Quickscreen system. However, the addition of graphite felt decreased the resistance from 18 to 5 kΩ. This device was proved to be useful to rapidly evaluate the electricity generation capacity of different bacteria.     

UASB-SBR组合工艺在丙烯腈废水处理中的应用研究

针对丙烯腈污水处理场存在的问题,提出采用UASB—SBR组合工艺处理丙烯腈废水的新工艺,并进行试验和讨论,获得了试验基础数据,为该厂丙烯腈污水处理装置技术改造提供技术支持。     

杭州交通噪声投诉点污染现状调查与防治

近年来杭州交通噪声投诉点主要分布在高架道路、立交桥和绕城高速附近的高层住户。对其中9个交通噪声投诉点的监测表明,昼间超4 a类标准的有4个,超标范围为0.1~7.6 dB;夜间9个点全部超4 a标准,超标范围为5.4~17.4 dB,夜间噪声超标特别严重。采用低噪声路面,设置隔声屏障,对敏感点安装通风隔声窗以及加强交通噪声管理等对策,可减轻交通噪声对敏感点的影响,从而减少交通噪声的投诉。     

A comparative investigation of NdSrCu_(1-x) Co_x O_(4-δ) and Sm_(1.8) Ce_(0.2) Cu_(1-x) Co_x O_(4-δ) (x:0–0.4) for NO decomposition

A series of single-phase T-structured NdSrCu 1-x Co x O 4-δ with oxygen vacancies and T -structured Sm 1.8 Ce 0.2 Cu 1-x Co x O 4-δ (x: 0–0.4) with oxygen excess were prepared using ultrasound-assisted citric acid complexing method, and characterized by means of techniques such as thermogravimetric analysis and NO temperature-programmed desorption (NO-TPD). The catalytic activities of these materials were evaluated for the decomposition of NO. It was found that the NdSrCu 1-x Co x O 4-δ catalysts were of oxygen vacancies whereas the Sm 1.8 Ce 0.2 Cu 1-x Co x O 4-δ ones possessed excessive oxygen (i.e., over-stoichiometric oxygen); with a rise in Co doping level, the oxygen vacancy density of NdSrCu 1-x Co x O 4-δ decreased while the over-stoichiometric oxygen amount of Sm 1.8 Ce 0.2 Cu 1-x Co x O 4-δ increased. The NO-TPD results revealed that NO could be activated much easier over the oxygen-deficient perovskite-like oxides than over the oxygen-excessive perovskite-like oxides, with the NdSrCuO 3.702 catalyst showing the best efficiency in activating NO molecules. Under the conditions of 1.0% NO/helium, 2800 hr -1 , and 600–900°C, the catalytic activity of NO decomposition followed the order of NdSrCuO 3.702 NdSrCu 0.8 Co 0.2 O 3.736 NdSrCu 0.6 Co 0.4 O 3.789 Sm 1.8 Ce 0.2 Cu 0.6 Co 0.4 O 4.187 Sm 1.8 Ce 0.2 Cu 0.8 Co 0.2 O 4.104 Sm 1.8 Ce 0.2 CuO 4.045 , in concord with the sequence of decreasing oxygen vacancy or oxygen excess density. Based on the results, we concluded that the higher oxygen vacancy density and the stronger Cu 3+ /Cu 2+ redox ability of NdSrCu 1-x Co x O 4-δ account for the easier activation of NO and consequently improve the catalytic activity of NO decomposition over the catalysts.     

海水养殖区沉积物中溴氰菊酯检测方法研究

根据海水养殖区沉积物特点,研究建立了其中溴氰菊酯提取、浓缩、净化方法,对溴氰菊酯及其杂质进行分离,用配有电子捕获检测器(ECD)的气相色谱仪测定.该方法具有简便、快速、灵敏度高和费用低等特点.通过对不同养殖区中沉积物进行加标试验测定,方法回收率为79.1%～99.3%,精密度3.6～7.1%.     

三峡库区滩坪滑坡治理工程锚索抗滑桩施工技术

介绍了采用泵送混凝土浇注抗滑桩和风动潜孔锤偏心跟管钻进方法作为治理三峡库区巴东县滩坪滑坡锚索抗滑桩的施工技术,为滑坡灾害防治提供了可供借鉴的工程施工措施.     

林州-安阳地区地下水三氮分布特征及其影响因素

本文分析了林州-安阳地区地下水的三氮分布特征,探讨了氮污染来源。运用Piper三线图、SPSS20软件,综合分析地下水化学特征,揭示氮循环作用机理。结果表明,研究区西北部主要为HCO_3-Ca-Mg型水,东部平原主要为HCO_3-Ca-Mg型水,其次为HCO_3-SO_4-Ca-Mg型、HCO_3-Cl-Ca型和HCO_3-Cl-Mg-Ca型水;氮污染源主要分布于林州市北部、安阳县北部、安阳市的东南部地区,其中农事活动、附近养殖场的畜禽排泄及污水排放是主要来源;地下水中存在着反硝化作用等氮的迁移转化现象,但是氮主要来源于附近的污染源。     

油气长输管道施工企业清洁生产研究

清洁生产在油气长输管道施工领域涉及较少,观念和方法还未完全推广。油气长输管道施工企业与传统生产型企业有许多不同之处,以某企业清洁生产审核为例,就如何通过清洁生产审核挖掘清洁生产潜力来做探索性、建议性的研究。实践证明,该企业清洁生产机会的突破口为柴油消耗,通过柴油消耗平衡图的建立和重点耗油设备运行状况的调查,找到了降低柴油消耗的清洁生产方案,使企业达到了“节能、降耗、减污、增效”的目的。