饮用水中挥发性卤代烃的顶空气相色谱分析研究

本文研究并拟订了一种饮用水中五种挥发性卤代烃的顶空气相色谱分析法，方法灵敏准确，操作简便快速，实际水样分析结果满意     

Organonitrate group concentrations in submicron particles with high nitrate and organic fractions in coastal southern California

During wintertime measurements in coastal southern California, organonitrate groups accounted for up to 10% of organic mass (OM) in submicron particles. In this study, we report the calibrated absorptivity, the uncertainties in the calibrations, the detection limits for 12 and 24 h ambient sampling, and the multipeak retrieval algorithm for the method developed. Organonitrate groups were observed when both submicron particle-phase nitrate and OM concentrations exceeded 1 μg m^?3. These high concentrations were associated with a mixed urban fossil fuel combustion source type that had potential source regions near Riverside and the South Coast Air Basin. The high frequency of these organonitrate observations contrasts with a number of studies of aerosol particles in other regions with more humid conditions, in which organonitrate groups were not detected and submicron sulfate concentrations exceeded those of nitrate. Our results suggest both that organonitrates form and/or exist in significant concentrations during polluted urban conditions and that their lifetime may be limited by hydrolysis in the particle phase.     

Physiological effects of tetracycline antibiotic pollutants on non-target aquatic Microcystis aeruginosa

This study aimed to evaluate the aquatic toxicity of three typical tetracycline antibiotics, including tetracycline, oxytetracycline, and chlortetracycline, on the cyanobacterium Microcystis aeruginosa. The cell density, chlorophyll a content, protein content, and enzymatic antioxidant activities were determined. The results showed that the cell growth was significantly inhibited by the three compounds at a low concentration. The chlorophyll a and protein content decreased significantly after exposure to 0.05 mg L^?1 of each compound for 9 d. When exposed to 0.2–1 mg L^?1 of tetracycline, the superoxide dismutase (SOD) activity increased, but peroxidase (POD) and catalase (CAT) activities decreased. In contrast, when exposed to oxytetracycline and chlortetracycline at different concentrations ranging from 0.2 to 1 mg L^?1 and from 0.01 to 0.05 mg L^?1, the SOD activity decreased, but the POD and CAT activities increased. These findings indicate that tetracycline antibiotics influence cell growth and protein synthesis, and they also induce oxidative stress in M. aeruginosa at environmentally similar concentrations. Thus, this study may provide further insights into the toxic effects of tetracycline antibiotics and the controlled use of antibiotics.     

电动汽车用电机及其控制器振动试验方法的探讨

振动试验是汽车产品设计验证和质量检验重要试验方法。本文主要从试验标准、试验条件、振动试验中主要参数的计算推导及应用、试验工装的设计、试验中应注意的问题等方面对电动汽车电机及其控制器的振动试验进行介绍。     

天津水质自动监测通讯系统─—电源易损及信息传输

本文对引进的天津水质自动监测系统在运行期间，通讯系统出现的故障作了全面的剖析研究，并提出了解决这些问题的方法。     

A new marine reptile from the Triassic of China,with a highly specialized feeding adaptation

The Luoping fauna (Anisian, Middle Triassic) is probably the oldest of Triassic faunas in Guizhou–Yunnan area, China. The reptilian assemblage is comprised of ichthyosaurs, a number of sauropterygians (pachypleurosaur-like forms), saurosphargids, protorosaurs, and archosauriforms. Here, we report on a peculiar reptile, newly found in this fauna. Its dentition is fence or comb-like and bears more than 175 pleurodont teeth in each ramus of the upper and lower jaws, tooth crown is needle-like distally and blade-shaped proximally; its rostrum strongly bends downward and the anterior end of its mandible expands both dorsally and ventrally to form a shovel-headed structure; and its ungual phalanges are hoof-shaped. The specializations of the jaws and dentition indicate that the reptile may have been adapted to a way of bottom-filter feeding in water. It is obvious that such delicate teeth are not strong enough to catch prey, but were probably used as a barrier to filter microorganisms or benthic invertebrates such as sea worms. These were collected by the specialized jaws, which may have functioned as a shovel or pushdozer (the mandible) and a grasper or scratcher (the rostrum). Our preliminary analysis suggests that the new reptile might be more closely related to the Sauropterygia than to other marine reptiles.     

微生物在生物煤层气形成中的作用及影响因素研究进展

在当今能源紧缺和环境污染严重的前提下,煤层气作为一类非常规天然气,越来越受到人们的重视。传统观点认为煤层甲烷多由高温热解产生,但是根据甲烷的同位素特征来判断,世界很多地方(包括我国鄂尔多斯、淮南等地)的煤层气多属生物成因或者生物和热成因混合。同时,越来越多的生物学证据也表明种类多样的产甲烷相关微生物广泛存在于煤层伴生地层水中或者煤层样品中。这也说明生物成因的煤层气仍然在不断地产生,这也为利用生物方法促进煤层气产生和利用提供了良好的契机。本文将介绍产甲烷微生物种群构成与功能、产气途径、影响产气速率的因素,探讨我国微生物强化产煤层气并实现产业化的应用前景。     

中国中小城镇生活垃圾"双解"处理技术研究

利用热重-红外光谱连用分析技术对生活垃圾中六种典型成分的热解特性进行研究,研究结果表明生活垃圾中食物残渣、木屑及纸三种生物质类组份的主要热解温度区间为150℃~600℃,热解过程中的主要挥发分为H2O、CO2、CO及含-COOH等多组分气体.PP、PVC及皮革三种人造制品的主要热解温度区间为200℃~500℃,热解过程中的主要挥发分包括CH4、CO2及CO等小分子气体等.根据热解特性研究结果,设计了一套适用于中小处理规模的生活垃圾的"双解"(热解气化+富氧分解)工艺,同时基于本工艺设计出一种新型卧式"双解炉".     

农村水污染防治源头控制政策与技术研究

从源头控制农业污染源进入水体,是实现水质提升的重要途径.目前中国农村污水防治政策制度进入强化和完善阶段,但在某些细化领域还存在空白.农村生活污水和畜禽养殖污水的治理技术比较成熟,而农业种植径流、水产养殖污水、坑塘污水等农村污染源,还未有相关的治理技术指南发布.建议从完善政策法规、强化执法和激励,做好农村发展规划,合理安排种植业、养殖业布局,以及加强资金投入与环境监管等方面加强农村水污染防治工作.