县域生态功能区划研究——以巩义市为例

文章结合河南省巩义市的实例,对县城小尺度生态功能区划分的方法和指标选取进行实际应用的探讨。巩义市生态功能区划采用2级分区（生态区和生态功能区）的等级体系。其中,生态功能区的划分采用定量与定性相结合的方法,定量分析中选取了形成生态系统特征、影响生态服务功能的14个特征因子进行聚类分析,在此基础上,再采用主导标志法进行区域划分。最后提出巩义市4个生态区和8个生态功能区的二级生态功能区划方案。     

Combined toxic impacts of thiamethoxam and four pesticides on the rare minnow (Gobiocypris rarus)

To examine pesticide mixture toxicity to aqueous organisms, we assessed the single and combined toxicities of thiamethoxam and other four pesticides (chlorpyrifos, beta-cypermethrin, tetraconazole, and azoxystrobin) to the rare minnow (Gobiocypris rarus). Data from 96-h semi-static toxicity assays of various developmental phases (embryonic, larval, juvenile, and adult phases) showed that beta-cypermethrin, chlorpyrifos, and azoxystrobin had the highest toxicities to G. rarus, and their LC₅₀ values ranged from 0.0031 to 0.86 mg a.i. L^?1, from 0.016 to 6.38 mg a.i. L^?1, and from 0.39 to 1.08 mg a.i. L^?1, respectively. Tetraconazole displayed a comparatively high toxicity, and its LC₅₀ values ranged from 3.48 to 16.73 mg a.i. L^?1. By contrast, thiamethoxam exhibited the lowest toxic effect with LC₅₀ values ranging from 37.85 to 351.9 mg a.i. L^?1. Rare minnow larvae were more sensitive than embryos to all the pesticides tested. Our data showed that a pesticide mixture of thiamethoxam–tetraconazole elicited synergetic toxicity to G. rarus. Moreover, pesticide mixtures containing beta-cypermethrin in combination with chlorpyrifos or tetraconazole also had synergetic toxicities to fish. The majority of pesticides are presumed to have additive toxicity, while our data emphasized that the concurrent existence of some chemicals in the aqueous circumstance could cause synergetic toxic effect, leading to severe loss to the aqueous environments in comparison with their single toxicities. Thence, the synergetic impacts of chemical mixtures should be considered when assessing the ecological risk of chemicals.

     

Explanation of heavy metal pollution in coal mines of china from the perspective of coal gangue geochemical characteristics

Environmental Science and Pollution Research - In the process of coal gangue surface accumulation and underground filling disposal, the heavy metals contained in coal gangue will inevitably...     

炼化企业VOCs排放现状及治理对策

简要介绍了挥发性有机物(VOCs)的定义及危害,分析了炼化企业的VOCs排放现状,并简要介绍了VOCs有组织和无组织排放的种类。介绍了中国石化济南分公司延迟焦化装置和柴油加氢装置针对有组织排放和无组织排放开展的各种治理措施及LDAR检测开展情况。     

石化企业玻璃钢设施静电特性及安全使用

通过测试玻璃钢设施的静电参数,研究分析玻璃钢设施的静电特性,表明玻璃钢设施有较大的静电危险性,提出了一般防静电措施,预防玻璃钢设施的燃爆风险。     

基于UML的放射源贮存库管理系统设计

随着放射性同位素在油井钻探、测试等领域中的广泛应用,放射源的种类及数量越来越大,使用频率越来越高,传统的管理方法已经不适应现代条件下的放射源管理需求。本文从放射源管理中的重要环节——贮存库管理系统入手,以UML为工具,对贮存库管理系统的需求模型和系统模型进行了设计,以提高放射源管理水平。     

Removal of trace Cr(VI) from aqueous solution by porous activated carbon balls supported by nanoscale zero-valent iron composites

Environmental Science and Pollution Research - In this study, porous activated carbon balls supported by nanoscale zero-valent iron composites (Fe@PACB-700) were used for the first time for the...     

GC/MS法测定润滑油基础油中多环芳烃

对润滑油基础油中多环芳烃的气相色谱/质谱(GC/MS)测定方法进行了研究,探讨了样品的提取,固相萃取柱净化等前处理方法,同时也对仪器测定条件进行了优化.结果表明,在检测润滑油基础油中多环芳烃时,经优化的GC/MS法的加标回收率和精密度均达到较满意的水平.     

无银催化-分光光度法测定COD的研究

以XS-LP为催化剂,探讨了改进的无银催化HACH法测定污水中COD的系列条件实验。结果表明:在药剂A,B的投配比为1∶2,投加总量为12 g/L的条件下,其准确度、精密度与国标法有较好的可比性,分别小于10%和3%;对实际废水的测量结果与国标回流法的相关系数分别高达0.9951和0.9874,可满足一般环境检测技术规范要求。     

Experimental thermal storage research of organic binary phase change materials in building environment

This paper aims to reveal the heat transfer mechanism of low-temperature phase change material (PCM) and design PCM heat storage device in building heating environment. Firstly, low-temperature binary PCMs of lauric acid and stearic acid are prepared, and their thermal properties are investigated by DSC. Then, shell and tube latent heat thermal energy storage units are conducted, and heat transfer experiments are carried out to analyze the heat transfer mechanism of PCM. The results demonstrate that natural convection plays an important role in heat transfer process, and the heat storage efficiency of PCMs can be significantly enhanced by increasing the fin width and improving the inlet heat transfer fluid (HTF) temperature. Furthermore, some proposals are put forward to guide the design of PCM storage device in building heating environment.