铜在鲤鱼(Cyprinus carpio)鱼鳃微环境中的形态分布

利用 Playle设计的装置测定了不同铜暴露水平下鲤鱼鳃部进出水中的游离铜离子浓度、粘液含量及有关参数 .用MINTEQA2和单配位体模型联合的试算方法计算了不同形态铜含量以及鳃部粘液对铜的络合能力 .结果表明 ,利用该算法可以获得鱼鳃微环境金属形态分布的准确结果 ,同时可以得到与鱼鳃粘液络合能力有关的参数 .随着暴露铜含量增加 ,粘液分泌量随之增加 ,鱼鳃微环境 p H和碱度也有所上升 .鱼鳃粘液的络合当量浓度 ( Cu/ C)和稳定常数 (对数 )分别为 0 .95mmol/ mg和5.32 .就铜形态分布而言 ,鱼鳃微环境与外部水相的主要差别表现在相对较高的羟基络合态铜含量以及占总量 3%～ 2 0 %的鱼鳃粘液络合态铜 .     

基于拟动力法抗滑桩加固非饱和土边坡稳定性分析∗

基于极限分析上限原理和拟动力法,提出一种半解析改进水平片分法,计算具有非线性分布特征的非饱和土重力和地震惯性力所做外功率,将传统塑性理论扩展至非饱和土中以考虑基质吸力对桩侧阻力的提升作用,与解析解对比验证了该方法的合理性。通过算例分析,揭示了吸力对非饱和土边坡稳定性及抗滑桩加固效果的强化作用,探究了非饱和土边坡的地震响应规律,研究了抗滑桩布设参数对支挡结构边坡稳定性的影响规律。研究结果表明：吸力对边坡稳定性的提升效果可达 20% ~ 50%,吸力效应与地震动特性密切相关,在地震波达到峰值时显著增强;水平和竖向加速度系数以及土剪切模量对边坡地震稳定性影响较大;桩距 D₁/d_p ≤ 4 时,抗滑桩加固效果较为显著并随摩擦角的增加得到强化,抗滑桩最佳桩位位于边坡中上部,且随摩擦角的增加逐渐减小,对应的加固效果也有所降低。     

钢渣在建筑材料中的易磨性和稳定性研究

针对目前钢渣处理和钢渣综合利用中存在的问题,指出对钢渣实施改质处理是提高钢渣资源化率的有效途径。通过高温成分改质、电子束辐照改质钢渣,和对钢渣改质机制的研究,解决钢渣应用中的体积不稳定性、易磨性和活性问题。该技术的研究可为寻求大宗量应用钢渣的途径和开发出高质量的钢渣产品奠定基础。     

培养基对菌产微生物絮凝剂的影响研究

研究了培养基成分种类及其用量对菌产微生物絮凝剂的影响。结果表明,较高的C/N比对菌产絮凝剂有利,碳源中的蔗糖是菌株Aeromonassp.N11产絮凝剂的良好碳源,氮源以采用复合氮源为佳。培养基中加入酵母膏有利于絮凝剂的产生。NaCl能够促进所产絮凝剂的絮凝活性,碳源蔗糖和氮源脲对菌产絮凝剂的影响最大。利用正交实验得出产絮凝剂培养基的最佳配比为蔗糖20g/L,酵母膏08g/L,脲05g/L,硫酸胺05g/L,NaCl7g/L。     

Impact of regulatory focus on express packaging waste recycling behavior: moderating role of psychological empowerment perception

Environmental Science and Pollution Research - To effectively solve environmental pollution and resource waste problems caused by the rapid growth of express packaging waste, government...     

某化工园区污水分类收集分质处理系统设计

为了提高某化工园区污水处理效率以及降低污水处理费用,园区环保部门拟对园区污水收集体系进行升级改造。改造方案采用分类收集分质处理的设计思路,同时创新型的采用OUR污泥呼吸法对企业废水分为难降解有毒、难降解无毒、可生化3类,3类废水进入不同的收集池后前2类废水进行芬顿+微电解预处理,可生化类别直接进入生化系统。该种工艺路线较传统的全部接入进行预处理的方法更具先进性、高效性和经济性,可作为一种先进理念的收集体系使用到其他工业园区中进行推广应用。     

巯基棉富集大气中汞的有效解吸方法研究

研究了DMA-80测汞仪对巯基棉富集汞的高效解吸方法。常温定速、定量洗脱巯基棉中汞发现,4.0 mol/L盐酸-氯化钠饱和溶液洗脱巯基棉中汞的效率为25%,而0.28%硝酸-3.5%氯化钠溶液(质量比为1∶12.5)洗脱汞效率不到5.6%,表明多数汞仍被富集,但4.0 mol/L盐酸-氯化钠饱和溶液洗脱巯基棉中汞效率稍高。用3种不同解吸方法探究巯基棉中汞回收率发现,超声波解吸汞效率高、耗时短,且低盐、低酸度、低成本的0.28%硝酸-3.5%氯化钠溶液可实现巯基棉中汞的高效洗脱;以4.0 mol/L盐酸-氯化钠饱和溶液及0.28%硝酸-3.5%氯化钠溶液分别为洗脱介质的微波消解法洗脱汞效率高于94.5%;正交试验得出洗脱介质为0.65 mol/L盐酸-氯化钠饱和溶液在95℃电热板中消解4 h含汞巯基棉后,解吸汞效率高于90%。     

Production of activated carbon from walnut shell by CO2 activation in a fluidized bed reactor and its adsorption performance of copper ion

Journal of Material Cycles and Waste Management - Low-cost and effective activated carbon for copper ion adsorption was prepared from walnut shell by CO2 activation in a fluidized bed. The effects...     

Temporal trends of lipophilic persistent organic pollutants in serum from Danish nulliparous pregnant women 2011–2013

The use of the lipophilic persistent organic pollutants (POPs) including polychlorinated biphenyls (PCBs) and several organochlorine pesticides (OCPs) has been prohibited for more than 30 years. In this study, we present the temporal trends of the lipophilic POP serum concentrations in Danish nulliparous pregnant women between 2011 and 2013. We randomly selected 197 pregnant women (gestational age 11–13) from the Aarhus Birth Cohort. The concentrations of the lipophilic POPs in the serum samples were analyzed using gas chromatography. The concentrations were corrected for total serum lipids. The statistical analysis was performed by regression analysis with adjustment for age, BMI, gestational age at blood draw, and smoking status. The serum concentrations of PCB 118, 138, 153, 156, 170, 180, 187, and hexachlorobenzen, trans-nonachlor, β-hexachlorocyclohexane (β-HCH), and p,p’-dichlorodiphenyldichloroethylene were lower in 2013 than in 2011. However, the oxychlordane concentration was lowest in 2011. The serum levels of most lipophilic POPs followed downward trends during the study period, which was expected, as these compounds has been banned for many years. The upward trend of oxychlordane was unexpected and presumably a chance finding.     

Occurrence and transformations of carbon,nitrogen, and phosphorus related to particle size fraction of sweet potato starch wastewater during hydrolytic acidification processes

Sweet potato starch wastewater (SPSW) is an industrial food-processing waste product, which is a significant pollution source due to its high chemical oxygen demand (COD), nitrogen, and phosphorus loads. The influence of hydrolytic acidification (HA) process on C, N, and P as well as other main parameters were evaluated. It is essential to treat these wastewaters with effective methods such as HA, a general pretreatment application. In this study, we investigate the scientific link between the changes of different fractions of C, N, and P with particle size distribution in response to the newly introduced HA process. Results showed that the levels of COD, TN, and TP remained ultimately stable; pH and suspended solids (SSs) decreased obviously. HA process exhibits excellent capability of reducing the larger particulars (with diameter of >5 μm) into smaller ones (with diameter of <0.1 μm). The most significant initial concentration contribution to COD, TN, and TP pollution came from particles and matter with a diameter of >5 μm, at 41.8, 57.3, and 43.5%, respectively. While the most significant contribution to COD, TN, and TP was resulting from micro-molecular size particles (<0.1 μm) after 48 h. The smallest particles (<0.1 μm) were the most dominant contribution to all pollutants measured, with COD, TN, and TP contributions of 63.2, 50.4, and 59.3%, respectively. While the contribution of larger particles (particle size >5 μm) reduced to 10.2, 15.3, and 7.1%, respectively.