红纺锤水蚤(Acartia erythraea)对Cu2+和Ag+的吸收

通过对桡足类动物红纺锤水蚤(Acartia erythraea)分别在Cu2 、Ag 、Cu2 Ag 混合溶液中的暴露实验,测定了其对Cu2 、Ag 的吸收速率常数、排出速率常数,并对Cu2 和Ag 在动物体内的分布状况进行了分析.结果表明,在单金属暴露的条件下,红纺锤水蚤对Cu2 、Ag 的吸收速度分别为1.09×104L·g-1·d-1、3.31×104L·g-1·d-1,排出速率常数分别为0.096 d-1、0.1056 d-1.而在Cu2 Ag 的混合暴露体系中,红纺锤水蚤对Cu2 、Ag 的吸收速率分别下降到9.17×103 L·g-1·d-1、2.87×104L·g-1-d-1,Cu2 和Ag 的排出速度常数则分别降到0.084 d-1和0.1008 d-1.动态模型的模拟结果表明,Cu2 和Ag 存在一定程度的拮抗作用.与暴露在单金属溶液中的红纺锤水蚤相比较,在暴露于Cu2 、Ag 混合体系中动物体内的非极性部分所占的比重明显增加,说明其在食物链中对于上一营养级的生物有效性将明显增加.     

电解法处理废料贵铅的电极极化研究

以含金银铅废料制成贵铅为原料,利用电化学热力学和动力学理论,对贵铅电解法实现金银与铅的分离和得到纯铅的电极过程极化行为与工艺条件的关系进行了研究。从而确定了贵铅电解时的电解液组成为［ｐｂ２＋］７０ｇ／Ｌ,温度为４０℃,β－萘酚／胶联合添加剂等工艺条件．同时根据动力学的研究证明了贵铅电解的电极反应速度受扩散控制,其扩散速度常数Ｋ扩＝１．９１７×１０－３ｃｍ／ｓ。扩散层厚度为０．００５１ｃｍ,在ηｋ＝７５ｍＶ时的阴极过程活化能为１６．１０ｋＪ／ｍｏｌ,为贵铅电解工业分离回收金银铅提供了可靠的理论依据和设计参数。     

A semipermeable membrane equilibrator for halomethanes in seawater

An equilibrator for sampling the partial pressures of halomethanes in seawater was designed and built, incorporating semipermeable membrane tubing to carry the gas phase. The equilibrator was tested for its ability to equilibrate chloromethane, bromomethane, iodomethane, and CFC-11. The residence time required for these halomethanes to equilibrate in the tubing (30 to 60 s) was determined experimentally. In a laboratory test, concentrations calculated from equilibrator measurements and based on published solubility values were found to differ by 6% to 16% from concentrations measured with a purge-and-trap apparatus, but uncertainties in the solubility values are likely to contribute significantly to the differences. In a comparison at sea, no significant difference was found between the semipermeable membrane equilibrator and another, more conventional equilibrator, except a 1.3% difference for CFC-11. This study demonstrates the feasibility of using semipermeable membranes in this and related applications.     

践行“两山”理论 促进农业农村绿色发展

分析、疏理习近平同志关于绿水青山就是金山银山的科学论断及主要内涵,深刻理解这一理念是对农业农村发展观的重大革命,为农业供给侧结构性改革指明了方向。树立和践行绿水青山就是金山银山的新发展理念,发挥其在农业农村绿色发展中的理论支撑作用,在转变农业生产方式和农民生活方式、调整农业产业结构、优化农村产业布局、催生新产业新业态、走“资源节约型、环境友好型”的绿色发展之路、建设美丽宜居乡村等方面具有指导意义。     

碳基高价银分子晶体电池处理LAS污染源水试验研究

以扬州第四水厂沉淀后的出水作为原水,模拟突发LAS污染,通过投加碳基高价银分子晶体电池进行应急处理的实验研究。实验结果表明：碳基高价银分子晶体电池对LAS的吸附,在30min内能达到81％的吸附容量;碳基高价银分子晶体电池对LAS的吸附,符合Freundlich吸附模式;溶液pH小于5时,吸附效果较好;对进水浓度小于4．75mg／L的LAS污染水样,接触时间在10min以内,便能使出水中LAS的浓度达到生活饮用水0．3mg／L的限值。     

表面增强拉曼光谱技术检测高氯酸根离子

高氯酸根离子是水质污染物中常见的污染源之一.通过化学还原法制备稳定、分散性好的纳米银溶胶颗粒(粒径为30～40 nm),并以此为基底,探究了利用表面增强拉曼光谱技术迅速准确地检测质量浓度为10-6～10-1 g/L的高氯酸根离子溶液的表面增强拉曼光谱.结果表明,当高氯酸根离子质量浓度为10-5～10-1 g/L时,随着高氯酸根离子浓度的降低,表面增强拉曼光谱强度逐渐减弱.     

复合光催化材料Ag-AgCl/石墨烯的制备及性能

以原位化学沉淀;光还原法制备了Ag-AgCl/石墨烯复合光催化材料。以罗丹明B为模型降解物,研究了其可见光催化性能。实验结果表明：石墨烯的引入使Ag-AgCl/石墨烯催化剂催化活性提高;当初始罗丹明B质量浓度为5 mg/L时,可见光照射60 min后罗丹明B的降解率可达99%;降解率随初始罗丹明B质量浓度的增加而减小。Ag-AgCl/石墨烯具有很高的可见光催化活性和稳定性。     

Silica nanoparticles and silver-doped silica nanoparticles induce endoplasmatic reticulum stress response and alter cytochrome P4501A activity

Engineered silica nanoparticles (SiO₂-NPs) find widespread application and may lead to exposure of humans and the environment. Here we compare the effects of SiO₂-NPs and SiO₂-NPs doped with silver (SiO₂-Ag-NPs) on survival and cellular function of human liver cells (Huh7) and Pimephales promelas (fathead minnow) fibroblast cells (FMH). In Huh7 cells we investigate effects on the endoplasmatic reticulum (ER), including ER stress, and interactions of nanoparticles (NPs) with metabolizing enzymes and efflux transporters. The NPs formed agglomerates/aggregates in cell culture media as revealed by SEM and TEM. SiO₂ and SiO₂-1% Ag-NPs were taken up into cells as demonstrated by agglomerates occurring in vesicular-like structures or freely dispersed in the cytosol. Cytotoxicity was more pronounced in Huh7 than in FMH cells, and increased with silver content in silver-doped NPs. Dissolved silver was the most significant factor for cytotoxicity. At toxic and non-cytotoxic concentrations SiO₂-NPs and SiO₂-1% Ag-NPs induced perturbations in the function of ER. In Huh7 cells NPs induced the unfolded protein response (UPR), or ER stress response, as demonstrated in induced expression of BiP and splicing of XBP1 mRNA, two selective markers of ER stress. Additionally, SiO₂-1% Ag-NPs and AgNO₃ induced reactive oxygen species. Pre-treatment of Huh7 cells with SiO₂-1% Ag-NPs followed by exposure to the inducer benzo(a)pyrene caused a significant reduced induction of CYP1A activity. NPs did not alter the activity of ABC transporters. These data demonstrate for the first time that SiO₂-NPs and SiO₂-1% Ag-NPs result in perturbations of the ER leading to the ER stress response. This represents a novel and significant cellular signalling pathway contributing to the cytotoxicity of NPs.     

从胶片生产废料中回收银

介绍了从涂布废水,废胶片、废乳剂中回收银的工艺流程,叙述了工业试验出现的问题和采取的措施。工业试验结果表明,对从上述３种废料中得到的湿银泥,采用培烧－置换－铸锭工艺回收银,回收率大于９９％,产品银锭的纯度大于９９．９％。     

Bio-mediated silver nanoparticle synthesis: mechanism and microbial inactivation

Even though plenty of literature is available on the biosynthesis of metal nanoparticles, there are serious lacunae on the mechanisms of their formation. In the present study, the mechanism of formation of mono-crystalline silver nanoparticles using a fruit extract of the ornamental tree Thevetia peruviana is emphasized, i.e. how the pH of the reaction mixture affected reaction kinetics and size of the nanoparticles. The facilitation of formation of Ag₂O at higher pH resulted in a faster rate of particle formation. The diameter of the bare particles at neutral pH determined by field emission scanning electron microscopy and the hydrodynamic diameter determined by dynamic light scattering were 53 and 104 nm, respectively. The silver nanoparticles exhibited good inactivation of Escherichia coli due to participation of free radicals as evidenced by electron spin resonance spectroscopy.