动态混合曝气-微电解预处理维生素B1生产废水

维生素 B1 生产废水具有有机污染物浓度高、色度大、水量冲击大和可生化性差等特点.为了减轻后续和生化处理的压力,提出了动态混合曝气-微电解工艺进行预处理,通过单因素对比试验考察了各因素对出水效果的影响,得出最佳控制参数为:进水 pH 值为 5,曝气时间为 2 h,铁碳体积比为 0.5,气水比为 200,充水比为0.5,混凝体积比为5.TOC(原水52 120 mg/L)和色度(原水为 1 000 倍)去除率分别达到 34.9%和44%,为后续生化处理奠定了坚实的基础.     

草莓蚜虫防治用药对蜜蜂的急性毒性与风险评价

为明确草莓蚜虫防治用药对蜜蜂的影响,按照《化学农药环境安全评价试验准则》和《化学品测试方法》要求测定了20%啶虫脒SP、10%氟啶虫酰胺WG和22%氟啶虫胺腈SC对意大利蜜蜂(Apis mellifera L.)的急性毒性,并采用危害商值(HQ)法进行了风险评价。急性毒性结果显示:20%啶虫脒SP、10%氟啶虫酰胺WG和22%氟啶虫胺腈SC对蜜蜂的急性经口毒性试验结果(48 h-LD50值)分别为4.47μg a.i.·蜂~(-1)、11.2μg a.i.·蜂~(-1)和0.0601μg a.i.·蜂~(-1),对蜜蜂的急性接触毒性试验结果(48 hLD50值)分别为11.0μg a.i.·蜂~(-1)、13.9μg a.i.·蜂~(-1)和0.643μg a.i.·蜂~(-1)。按《化学农药环境安全评价试验准则》中毒性等级划分标准,20%啶虫脒SP、10%氟啶虫酰胺WG和22%氟啶虫胺腈SC对蜜蜂的毒性等级分别为中毒、低毒和高毒。风险评价结果表明,22%氟啶虫胺腈SC对蜜蜂存在中等风险(HQ值为1 622),20%啶虫脒SP和10%氟啶虫酰胺WG对蜜蜂的风险为低风险,其HQ值分别为40.3和6.70。因此,草莓生产中可优先选用10%氟啶虫酰胺WG来防治蚜虫,20%啶虫脒SP次之。而使用22%氟啶虫胺腈SC时,应注意采取措施降低其对蜜蜂的毒性风险,以免造成危害。     

有机氯农药硫丹的生殖毒性及其机制研究进展

硫丹作为一种广谱有机氯农药,在农业区域周边的土壤和水体中都存在较高残留,2011年被斯德哥尔摩公约列入持久性有机污染物(POPs)名单。硫丹已被证实对神经系统、心血管系统、肝、肾等具有毒性作用,关于其生殖毒性的研究很多,但潜在机制尚不完全清楚。本文总结了硫丹导致的不同动物的生殖毒性,并从生殖器官和生殖细胞损伤、氧化应激以及DNA损伤、生殖细胞周期阻滞及细胞凋亡等方面,对近年来硫丹生殖毒性及其作用机制研究进展进行综述,并对其中存在的问题进行讨论,以期有助于深入了解硫丹的毒性效应。     

不同测试方法评估48%毒死蜱乳油对玉米田施药者的人体暴露风险

本研究选取3种不同暴露环境,分别为玉米株高达到施药者膝盖左右(暴露环境1)、达到施药者腰部左右(暴露环境2)和高于施药者身高(暴露环境3),采用手动背负式喷雾器,在这3种暴露环境中施喷48%毒死蜱乳油(EC,稀释500倍),通过贴片法和全身整体测试法(whole body dosimetry,WBD)分析了施药者农药皮肤暴露量(dermal exposure,DE)。依据试验结果,发现在暴露环境1和2中,2种测试方法的农药潜在皮肤暴露量(potential dermal exposure,PDE)无显著性差异,但在暴露环境3中,2种测试方法的PDE之间存在显著性差异(LSD0.05=57.9);对施药者的主要暴露部位进行分析,发现在暴露环境1和暴露环境2中2种测试方法的暴露部位类似,但在暴露环境3中显示,贴片法为手部,全身测试法为上半身(头、颈、前胸、后背及手臂)。使用全身测试法测定PDE同时测定直接皮肤暴露量(actual dermal exposure,ADE),并利用ADE和PDE计算外穿防护服(运动服)渗透率的结果,3种暴露环境分别为4.69%、5.19%和5.54%,比通常假设的防护服或工作服的10%渗透率小。     

Human ecological effects of tropical storms in the coastal area of Ky Anh (Ha Tinh,Vietnam)

Vietnam is prone to tropical storms. Climate change effects contribute to sea level rise, floods, progression of the low water line and coastal erosion. This paper inventories the perception of local people, assesses and values main aspects of the livelihood damage caused by the tropical storms of the period 2008–2013 in three coastal communes of the Ky Anh District of the Ha Tinh Province in Central Vietnam. The communes were selected because the location of their coastal line is perpendicular to the storm itself, which made them prone to damage. The effects of increasingly extreme weather conditions on three communities in an area most affected by storms and floods on the local residents and their responses to these changing environmental conditions are analyzed and assessed. The results of questionnaires completed by randomly selected local inhabitants of these communes show that storms and related hazards such as flood, sea level rise and heavy rain are perceived as the most impacting climate change intensified phenomena on agriculture and aquaculture, livestock, household property and income. Opinions and measured data provided by the commune and district authorities allow estimating the total direct cost of the tropical storm at 1.56 million $US (The used conversion rate VND/$US is 21,730 when the research was conducted in 2014) during the period 2008–2013. The long-term costs of adaptation and social impact measures will be significantly higher. Details of the monetary figures allow identifying the physical and natural capital of the area as being most affected by the storm. Trend and cost analysis show that the total financial support for hazard prevention and management during 2014–2019 is estimated at 1.19 up to 1.32 million $US. Local stakeholders indicate that climate change adaptation should not be limited to technical measures such as strengthening dikes, but also should target planting protection forests and mangroves and land use planning. Financial support for the relocation policy, stakeholder involvement and integrating climate change adaptation in both the socioeconomic development master plan and local land use planning are also of importance.     

相变溶剂捕集CO2技术的研究进展

化学溶剂吸收法是目前应用最广泛的燃烧后CO₂捕集技术。介绍了化学溶剂吸收法的基本原理,综述了化学溶剂吸收法的研究现状,比较分析了几种常用CO₂吸收剂的优缺点。重点阐述了两类新型相变吸收剂（液-液相变溶剂和液-固相变溶剂）的研究进展。指出：新型相变溶剂是理想的CO₂吸收剂,用其捕集CO₂可有效降低吸收剂的再生能耗;相变溶剂吸收CO₂的传质反应动力学以及不同类型相变溶剂的挥发和降解特性应作为今后该领域的研究重点。     

钯负载泡沫镍电极电化学还原水中三氯乙酸

采用非电沉积法制备了钯负载泡沫镍电极,运用SEM技术对其进行了表征,并以其阴极、铂丝为阳极进行了电化学还原三氯乙酸的研究,考察了工艺条件对三氯乙酸降解效果的影响,并对反应动力学和反应机理和进行了探讨。结果表明:钯负载泡沫镍电极具有较高的比表面积和良好的储氢性能;以20 mmol/L硫酸钠为电解质,在电解温度为20℃、钯负载量为4.5 mg/cm~2的条件下恒流(10 mA)电解240 min,三氯乙酸降解率达99.76%,氯原子脱除率达73.86%;三氯乙酸的电化学还原反应过程以及三氯乙酸上未脱除氯原子浓度的变化均符合拟一级反应动力学方程;三氯乙酸在电化学还原过程中逐个脱除氯原子。     

运用证据权重与确定性系数合成模型进行钉螺-环境因子的空间关系研究

钉螺是血吸虫唯一中间宿主,研究钉螺与孳生环境因子的空间关系对采取有效的查螺、灭螺措施有重要的科学和社会价值。以鄱阳湖恒湖农场茶叶港草洲为研究对象,应用证据权重法与确定性系数法合成模型研究植物南荻、苔草、藜蒿、土壤温度、土壤湿度、导电率、海拔高程7个证据因子与"钉螺出现与否"的空间关系。结果表明:研究区内一定范围内高程的增加易于钉螺孳生;钉螺在湿度相对较大(大于0.35%(m~3/m~3))的环境中分布较少;苔草丰度过大(高于4 368 cm~3/m2)过小(低于1 457 cm~3/m2)都不利于钉螺孳生;钉螺较易孳生在南荻丰度较大(高于2 745 cm~3/m2)的区域;电导率较高(高于0.07 m S/cm)区域钉螺较少;土壤温度在16~20℃范围利于钉螺孳生。在模型预测结果图中,占研究区总面积13.7%的极高易发区的较小范围内预测到82%的钉螺空间分布,评价曲线的曲线下面积高达88.7%,说明模型的预测成功率很高,表明该模型适合研究区域钉螺孳生与其影响因子之间的空间关系。     

Research on central village selection in western underdeveloped region: a case study of Lidian Town,Jingning County,Gansu Province,China

Central village selection is the priority of small town construction. Depending on the development potential analysis, classification analysis, and quantitative and qualitative analysis, this article systematically proposes the specific methods of central village selection and also constructs the indicator system used in central village selection in small towns of western underdeveloped region in China. The article also puts forward ideas and methods for selection of central village in the western underdeveloped region through an empirical research on Lidian Town, Jingning County, Gansu Province. In the final part, suggestions and recommendations on how to develop central village for Lidian Town are made.     

Evaluation of the European Space Agency Climate Change Initiative Soil Moisture Product over China Using Variance Reduction Factor

In this study, we evaluated the European Space Agency Climate Change Initiative soil moisture product v02.1 (ESA CCI SM v02.1) using in situ observations collected at 547 stations in China from 1991 to 2013. A conventional validation was first conducted, and the triple collocation errors of ESA CCI SM and the European Centre for Medium Range Weather Forecasting reanalysis data were approximately 0.053 and 0.050 m³/m³, respectively. To obtain more reliable validation results, the average soil moisture of the in situ observations per ESA CCI SM pixel was also used as the validation sites. Variance reduction factor (VRF) was adopted to quantify the accuracy of the soil moisture validation sites, and the average VRF was estimated at 4.88%. The validation results were enhanced by excluding validation sites with VRF errors greater than 5% from the statistical analysis. Although the ESA CCI SM underestimated the in situ observations with a Bias of 0.05 m³/m³, a moderately high correlation coefficient of 0.44 and a relatively small unbiased root‐mean‐square difference of 0.05 m³/m³ were observed. This study provides information on the utilization of ESA CCI SM for ecological protection, climate change, and hydrological forecasting. It also suggests the adoption of VRF for future error corrections of satellite‐based products.