新鲜蔬菜和水果中亚硝酸盐测定方法研究

本文研究了消除新鲜蔬菜和水果中抗坏血酸对亚硝酸盐测定原方法,在样品提取时加入醋酸锌和活性炭,以消除抗坏血酸对测定的干扰,提高了测定的灵敏度和准确必     

宣城向阳剖面网纹红土粒度端元分析及指示意义

对宣城向阳剖面的109个网纹红土样本做粒度分析和地球化学元素分析,并对粒度数据采用合适的端元分解方法,将各端元与地球化学指标在深度上进行了对比.结果 认为:端元法可以把代表此区域3种不同动力的沉积端元(EM)分离出来,并可以定量地分析各自所占比重及各个阶段每种动力各自的沉积变化.EM1明显指示着对原有沉积物的成壤改造作...     

试论畜牧业污染和畜产品公害与绿色环保畜牧业

分析了畜牧业发展给环境带来的影响、环境污染给畜牧业的生产带来的影响以及被污染的畜产品给人类带来的危害；提出了建立绿色环保畜牧业的基本思路。     

油污土壤堆制处理实验研究

堆制处理工艺是处理油污土壤的一种强化的生物处理工艺 .通过实验室实验 ,结果表明 :原油降解菌剂投加量 6× 10 12个 (CFU) kg(土壤 )、营养物投加量为使土壤中C∶N∶P =10 0∶2 5∶0 2 5、土壤含水量为饱和含水量的 30 %— 70 %、通风量 14 0mL s为适宜处理条件 ,此时 ,处理 2个月 ,油去除率在 5 0 %以上 .在油污土壤中添加的降解菌和营养物种类、数量完全相同时 ,堆制处理效率明显高于生物耕翻处理效率 ;在相同处理时间内 ,堆制处理时油去除率可比生物耕翻处理时提高 10 %以上 .在处理过程中 ,原油中大部分饱和烃和芳香烃组份被降解     

苯系化合物好氧生物降解性研究

选用城市污水处理场的活性污泥做菌源，研究了苯、甲苯、邻－间－、对－二甲苯、乙基苯、三甲苯等七种芳香化合物的好氧生物降解规律。实验结果表明，七种化合物浓度在１０ｍｇ／ｌ左右时，在实验周期内能全部降解；浓度在４０－１８０ｍｇ／ｌ时，有的化合物不能被降解。七种化合物降解的难易程度为：甲苯＞间二甲苯＞苯＞对二甲苯＞乙基苯＞三甲苯＞邻二甲苯。此外，实验结果还表明，化合物的降解性受苯环上取代基数量及位置等因素     

Characteristics of atmospheric volatile organic compounds in urban area of Beijing: Variations, photochemical reactivity and source apportionment

Atmospheric volatile organic compounds (VOCs) were observed by an on-line gas chromatography-flame ionization detector monitoring system from November 2016 to August 2017 in Beijing. The average concentrations were winter (40.27 ± 25.25 μg/m³) > autumn (34.25 ± 19.90 µg/m³) > summer (32.53 ± 17.39 µg/m³) > spring (24.72 ± 17.22 µg/m³). Although benzene (15.70%), propane (11.02%), ethane (9.32%) and n-butane (6.77%) were the most abundant species, ethylene (14.07%) and propene (11.20%) were the key reactive species to ozone formation potential (OFP), and benzene, toluene, ethylbenzene, m-xylene + p-xylene and o-xylene (54.13%) were the most reactive species to secondary organic aerosol formation potential (SOAFP). The diurnal and seasonal variations indicated that diesel vehicle emission during early morning, gasoline vehicle emission at the traffic rush hours and coal burning during the heating period might be important sources. Five major sources were further identified by positive matrix factorization (PMF). The vehicle exhaust (gasoline exhaust and diesel exhaust) was found to be contributed most to atmospheric VOCs, with 43.59%, 41.91%, 50.45% and 43.91%, respectively in spring, summer, autumn and winter; while solvent usage contributed least, with 11.10%, 7.13%, 14.00% and 19.87%, respectively. Biogenic emission sources (13.11%) were only identified in summer. However, both vehicle exhaust and solvent usage were identified to be the key sources considering contributions to the OFP and SOAFP. Besides, the contributions of combustion during heating period and gasoline evaporation source during warm seasons to OFP and SOAFP should not be overlooked.     

Assessing the Eutrophication of Shengzhong Reservoir Based on Grey Clustering Method

Abstract

Reservoir water environment is a grey system. The grey clustering method is applied to assessing the reservoir water environment to establish a relatively complete model suitable for the reservoir eutrophication evaluation and appropriately evaluate the quality of reservoir water, providing evidence for reservoir management. According to China’s lakes and reservoir eutrophication criteria and the characteristics of China’s eutrophication, as well as certain evaluation indices, the degree of eutrophication is classified into six categories with the utilization of grey classified whitening weight function to represent the boundaries of classification, to determine the clustering weight and clustering coefficient of each index in grey classifications, and the classification of each clustering object. The comprehensive evaluation of reservoir eutrophication is established on such a foundation, with Sichuan Shengzhong Reservoir as the survey object and the analysis of the data attained by several typical monitoring points there in 2006. It is found that eutrophication of Tiebian Power Generation Station, Guoyuanchang and Dashiqiao Bridge is the heaviest, Tielusi and Qinggangya the second, and Lijiaba the least. The eutrophication of this reservoir is closely relevant to the irrational exploitation in its surrounding areas, especially to the aggravation of the non-point source pollution and the increase of net-culture fishing. Therefore, it is feasible to use grey clustering in environment quality evaluation, and the point lies in the correct division of grey whitening function     

办公室电脑操作者的职业危害研究

本文以研究电脑办公作业的职业危害为出发点,详细分析了电脑办公可能对人类身体、心理及大脑等多个方面造成的伤害,并在此基础上,针对不同类型的伤害从预防电脑辐射以及安全人机工程学的角度上提出了相应的预防措施,并得出以下几点结论:从安全人机的角度,应改进现有的办公家具,设计出更加安全、人性的办公家具,将电脑办公的职业危害降到最低;办公时应采取正确的操作方法,同时注意不要长时间地持续使用电脑并注意加强预防辐射的防范措施.     

基于常规处理的微污染水源水处理工艺改进措施简

我国大部分给水处理厂主要采用混凝-沉淀-过滤-消毒的常规处理工艺,该工艺对有机物、氨氮等去除效果有限,同时存在消毒副产物残留等问题。根据我国经济发展现状,分析了常规处理工艺的改进措施,包括对常规工艺进行强化,在常规处理工艺之前增加预吸附和预氧化,在常规处理工艺之后增加臭氧-生物活性炭吸附、膜处理等。这些措施在保留原处理工艺的基础上,通过调整操作条件或增加处理设施来改善出水水质,具有投资少、见效快的特点。     

应用生物配体模型研究湘江水体中铜的生物有效性

为评估湘江水体中铜的生物有效性,通过铜对青鳉的急性毒性实验确定铜对青鳉的半致死浓度(LC₅₀),然后利用生物配体模型(Biotic Ligand Model, BLM)确定青鳉的累积半致死浓度(LA₅₀)。同时对湘江水样的预测结果表明,铜对青鳉的LA₅₀为12.43 nmol?gw^-1;BLM预测的与实验观测的LC₅₀差异倍数小于2,表明BLM预测结果非常准确。在此基础上预测铜对青鳉LC₅₀预测范围为344.70～761.96 μg?L^-1。湘江各点水质最终急性值(FAV)相差不大(11.04～14.25 μg?L^-1),但水中溶解态铜含量相差较大(0.29～10.48 μg?L^-1),同时毒性单位值(TU)相差较大(0.06～1.48 μg?L^-1),其中最小值在舂陵水入湘江下游采样断面,最大值在株洲断面。在全部调查断面中,只有株洲断面TU大于1(1.48),说明株洲断面水中铜含量超过了该断面水中BLM确定的标准最大浓度1.48倍。