几种农药对鲤鱼脑AchE的联合毒性效应

采用体内染毒的方法,以鲤鱼脑乙酰胆碱酯酶(AchE)活力为指标,研究了有机磷农药对硫磷与氯乐果、甲胺磷涕灭威之间的联合毒性效应.结果表明,这些农药之间均产生较强的协同作用,但是两种农药以不同比例加入,其产生的毒性效应有明显差别,涕灭威/对硫磷之间的协同作用要强于同类农药间的作用.     

SiO_3~(2-)离子的加入对脉冲倒极电解合成PASiC的研究

探索了试验过程中SiO2 -3 离子团的加入对脉冲自动倒极电解法合成聚合氯化硅酸铝中Alb 含量的影响。通过试验确定了最佳摩尔比。在脉冲倒极周期和电解槽电流一定的情况下 ,当总铝AlT 与SiO2 -3 的摩尔比为 10∶1～ 2 0∶1时 ;在此合成条件下制备液中Alb 含量超过 80 % ;处理模拟水样最佳投药量为 :0 5～ 5mgAl2 O3 /L。在制备过程中 ,极化现象得到了极好的控制 ,电解槽电压和电流十分稳定     

Photocatalytic oxidation of triclosan

In the spring of 2003, there was an outbreak of the severe respiratory syndrome (SARS) in Hong Kong. Health concerns have thus triggered an increased and predominant use of various types of household cleansing agents such as triclosan (5-chloro-2-(2,4-dichlorophenoxy)phenol). However, it has been reported recently that triclosan could be photochemically converted to toxic 2,8-dichlorodibenzo-p-dioxin (2,8-Cl(2)DD) in the environment. It is therefore necessary to develop environmentally friendly methods for the treatment of triclosan. To this end, photocatalytic degradation of triclosan in aqueous solution was conducted using TiO(2) (Degussa P25) under irradiation of UV light (lambda < 365 nm). It was found that triclosan could be degraded by this approach. Hydrogen peroxide was added to enhance the degradation process, and the optimal initial hydrogen peroxide concentration for triclosan degradation was 0.005% (w/v). Product identification indicated that triclosan oxidation occurred at its phenol moiety and yielded quinone and hydroquinone intermediates. The formation of a dichlorophenol intermediate in triclosan degradation suggested bond-breaking of the ether linkage occurred during the process. Moreover, no chlorinated dibenzo-p-dioxin congener was detected. These findings confirm that the photocatalytic degradation of triclosan is an environmentally friendly process.     

Low digestibility of phytate phosphorus,their impacts on the environment,and phytase opportunity in the poultry industry

Environmental Science and Pollution Research - Phosphorus is an&nbsp;essential macro-mineral nutrient for poultry, needed for the body growth, development of bones, genomic function, good...     

Metal removal with two biochars made from municipal organic waste: adsorptive characterization and surface complexation modeling

The adsorptive characteristics of biochar produced from garden green waste (S-char) and a mixture of food waste and garden green waste (FS-char) were investigated. Adsorption of Cu²⁺, Zn²⁺, and Mn²⁺ onto the two biochars reached equilibrium within 48 hours. The metal adsorption was effectively described by the pseudo-second-order kinetic and Freundlich isotherm models which suggest heterogeneous chemisorption. The initial solution pH influenced adsorption of Zn²⁺ and Mn²⁺ but not of Cu²⁺. Simulation via a surface complexation model showed that the fraction of XOCu⁺ adsorbed onto biochar was increased with increasing pH until it reached the adsorption maximum at pH 8.5, while the endpoint for the maximum of XOMn⁺ was higher than pH 12.     

Polychlorinated dibenzo p-dioxins and dibenzofurans emissions in a primary copper smelter in China

Metallurgical production is the largest polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F) emission source in China. However, PCDD/F monitoring and research are rarely conducted on primary metallurgical production. In this study, a demonstration primary copper smelter in China was selected to investigate PCDD/F characteristics and control. Samples were collected from major PCDD/F release points in the smelter process (fly ashes and waste water sludge). Specific analysis of PCDD/F congeners was carried out using a high resolution gas chromatography/high resolution mass spectrometry method. The results showed that PCDD/Fs might be unintentionally produced in the primary copper smelter processes, with sample concentrations of 180–6110 pg/g dry wt; highly chlorinated PCDD/F homologues were predominant. The toxicity of all the samples was calculated to be 120 pg WHO TEQ/g, fly ashes from the refining process furnaces air pollution control device and sludge were hazardous waste with higher PCDD/F toxicity. Both precursor formation and de novo synthesis were found to contribute to PCDD/F formation in the smelter process. PCDD/F characteristics and formation were compared with reported secondary copper smelters. Life-cycle control of PCDD/F was proposed for retrofitting of this smelter and for similar plants in China's primary copper production sector, including control at the PCDD/F formation, removal and disposal stages.     

丙酮丁醇梭菌Clostridium acetobutylicum CICC 8012发酵鲜芭蕉芋生产丁醇

以非粮作物鲜芭蕉芋为原料,利用丙酮丁醇梭菌CICC 8012发酵生产丁醇.采用中心组合实验设计(CCD),选取初始糖浓度、接种量、中性红、乙酸铵为主要影响因素,对发酵条件进行优化,建立以丁醇产量为响应值的数学模型.对模型求解得到:初始糖浓度62.25 g/L,接种量为10.81%,中性红为0.81 g/L,乙酸铵为0.574 g/L时,最终的丁醇产量为12.83 g/L.验证实验结果表明,在优化条件下丁醇发酵产量达到12.73 g/L,证明了模型可靠有效.     

铋膜丝网印刷电极现场快速测定工业废水中Pb2+、Cd2+

采用丝网印刷电极,通过同位镀铋膜阳极溶出伏安法对工业废水中重金属Pb2+和Cd2+进行了快速测定,考察并优化了镀铋膜及测定金属离子的实验条件.实验结果表明,Pb2+和Cd2+在铋膜电极上可得到灵敏的溶出峰,在优化的实验条件下Pb2+和Cd2+在50—500μg.L-1范围内呈现良好的线性关系,相关系数分别为0.9947、0.9969,检测限分别为4.45μg.L-1和2.98μg.L-1.测定了工业废水中的Pb2+、Cd2+,结果与ICP-MS方法一致.     

胚胎期和哺乳期全氟辛烷磺酸(PFOS)暴露致大鼠学习记忆能力下降

为了探讨全氟辛烷磺酸(PFOS)的发育神经毒性,寻找PFOS发育神经毒性作用的敏感期,利用水迷宫和组织病理切片技术,研究了胚胎期和哺乳期暴露于PFOS后新生大鼠发育情况、学习记忆能力、抓力以及海马组织病理学改变。结果显示：PFOS导致仔鼠发育迟缓,睁眼期延迟。仔鼠出生后体重与对照组相比出现显著性降低。同一PFOS暴露浓度下,胚胎期暴露组体重低于哺乳期暴露组,抓力差异不显著。水迷宫实验结果显示,TT15(胚胎期和哺乳期均暴露于15 mg·L^-1 PFOS)和TC15(仅胚胎期暴露于15 mg·L^-1 PFOS)暴露组仔鼠逃避潜伏期显著高于对照组,且TC15暴露组仔鼠逃避潜伏期显著性高于CT15(仅哺乳期暴露于15 mg·L^-1 PFOS)暴露组。空间探索实验中,TT15暴露组仔鼠在目标象限的游泳时间显著性低于对照组,其他组无显著性差异。组织病理切片结果显示暴露组海马组织细胞数量减少,出现细胞凋亡现象。结果表明,PFOS造成仔鼠的发育延迟以及学习记忆能力下降的关键作用时期可能是胚胎期。     

生态产品价值实现的“一村万树”绿色期权模式

随着经济的不断发展，越来越多的国家和地区开始重视绿色高质量发展，对生态产品的研究也在不断加强。各种政策工具相继出现，致力于将自然给予的生态产品资本化，并赋能经济发展。其中，衢州市柯城区的“一村万树”项目就是一种具有创新性的生态产品价值实现模式。本文对衢州市柯城区“一村万树”项目及其绿色期权模式进行研究，结合部门统计数据和空间信息数据，对“一村万树”项目实施区2018年的生态效益进行核算，并选取柯城区2010—2018年相关社会经济统计数据进行相关性分析，探析项目的社会经济效益，最后在量化分析的基础上结合公共池塘资源治理的八条设计原则，定性分析了“一村万树”绿色期权的合理性。结果显示：“一村万树”实施区2018年的生态效益为124.63亿元，约为研究区国内生产总值估算值的1.68倍，说明该项目具有巨大的生态效益；同时，相关分析结果表明该项目实施对当地第三产业的发展有较大的促进作用。柯城区“一村万树”项目以及绿色期权模式给当地带来了巨大的生态和社会经济效益，为我国的乡村绿化建设和生态产品价值实现提供了一种新范式。