Effect of titanium dioxide nanoparticles on the expression of apoptotic markers in mouse blastocysts

Oocyte maturation, embryo development and expression of apoptotic-specific genes were evaluated in blastocysts of mice treated with titanium dioxide nanoparticles. Female mice received 0, 50 or 100?mg/kg/day titanium dioxide intraperitoneally for five consecutive days. After the last injection, pregnant mare serum gonadotropin and, 48?h later, human chorionic gonadotropin were administered intraperitoneally for induction of ovulation. After 14?h, mice were sacrificed and oocytes were collected. The number of mature oocytes was evaluated and then fertilization was carried out in vitro and the numbers of fertilized and cleaved oocytes and of blastocysts and the expression of Bax, caspase 3, and Bcl-xL genes in blastocysts were evaluated. The number of mature, fertilized and cleaved oocytes and of blastocyst embryos in the experimental groups were not different from control. The expression of Bax and caspase 3 genes was significantly elevated in the experimental groups compared to control, while expression of the Bcl-xL gene was significantly lower in the high dose group. Uptake of titanium dioxide nanoparticles at daily doses of 50?mg/kg and more may affect embryo development by alteration of pro-apoptotic and anti-apoptotic gene expression.     

Titanium nanoparticles attenuates arsenic toxicity by up-regulating expressions of defensive genes in Vigna radiata L

Arsenic(As)-toxicity is recognized as one of the major environmental problems,affecting productivity of crops worldwide,thereby threatening sustainable agriculture and food security.Progression in nanotechnology and its impacts have brought up concerns about the application of engineered nanoparticles(NPs) in various sectors of the economy,including the field of agronomy.Among various NPs,there has been a rising amount of interest regarding the effects of titanium NPs(TiNPs) on plants growth and development,and their fate of abiotic stress tolerance.Hence,the present study was aimed to assess the ameliorative potentialities of chemically and biologically/green synthesized TiNPs to alleviate As-induced toxic responses in Vigna radiata L.The results revealed that exposure to As hindered the growth indices(radicle length and biomass) and membrane integrity,while were improved with the application of chemical and green synthesized TiNPs.In addition,treatment of As provoked the accretion of reactive oxygen species(superoxide and hydrogen peroxide) and malondialdehyde(a lipid per oxidized product),but were diminished by the supplementation of chemical and green manufactured TiNPs.The experimental data also signified that exogenous application of chemical and green synthesized TiNPs conferred tolerance to As-induced oxidative injuries via perking-up the expressions of antioxidant genes and enzyme systems viz;superoxide dismutase and catalase.Therefore,the present study inferred that chemically and green synthesized TiNPs,particularly green manufactured,effectively mitigated the adverse impacts of As by augmenting antioxidant machinery,thereby proving its potentiality in the alleviation of As-toxicity,at least in Vignaradiata L.     

亚甲基蓝溶液的光催化脱色及降解

以高压汞灯为光源,在自ＴｉＯ２纳米粉末悬浮体系内,以在蓝溶液光催化降解脱色反应为模型,研究了其脱色降解动力学及其影响因素。研究表明,亚甲基蓝光催化反应动力学常数为４．５３μｍｏｌ／Ｌ．ｍｉｎ．吸附常数为３３．５５Ｌ／ｍｍｏｌ;随着ｐＨ值的上升以及Ｈ２Ｏ２的加入,其脱色降解速率加快。     

钛合金叶片防护涂层研究--十五科研项目工作总结

针对先进航空发动机压气机用钛合金,研究真空多弧离子镀技术在钛合金上制备ZrN抗冲蚀防护涂层及NiCrAlY抗氧化防护涂层工艺。结果表明,ZrN涂层大大提高了钛合金的抗冲蚀性能,扩散障＋NiCrAlY涂层有效地抑制了钛合金的氧化,涂层对钛合金起到了很好的防护作用,并制备了钛合金叶片涂层样件。     

Removal of nanoparticles by coagulation

<正>Nanoparticles(NPs)from anthropogenic sources have applications in several commercial products,including cosmetics,pharmaceuticals,and materials.There is evidence that during their usage and disposal,engineered nanoparticles can and will be released into wastewater(Gottschalk et al.,2013;Pasricha et al.,2012;Westerhoff et al.,2013;Zheng et al.,2015).If water and wastewater treatment plants are inefficient or incapable of removing NPs from water,NPs will be released with the treated effluent,entering drinking water sources and natural aquatic environments,increasing exposure for plants,microorganisms,     

活性炭负载TiO2光催化杀菌研究

研究了溶胶-凝胶法制备活性炭颗粒负载TiO2的光催化杀菌作用,探讨了光催化剂的最佳制备条件。实验结果表明,光催化杀菌效果明显好于单独紫外光的杀菌效果,当钛酸丁脂与无水乙醇比例为1:8制备TiO2溶胶,活性炭颗粒浸涂凝胶一次、在450℃煅烧2h,20min的杀菌率可达88%,在溶胶中掺杂Fe3+的杀菌率可达到95%,提高了活性炭负载TiO2的光催化活性。     

Sulfur-oxidizing autotrophic and mixotrophic denitrification processes for drinking water treatment: elimination of excess sulfate production and alkalinity requirement

The activity of copper oxide, titanium carbide and silicon nitride nanoparticles for the oxidative degradation of environmentally relevant concentrations (μg L⁻¹ range) of enrofloxacin - an important veterinary antibiotic drug - in aqueous solutions was investigated. With hydrogen peroxide as an oxidative agent, both copper oxide and titanium carbide decrease the concentration of enrofloxacin by more than 90% over 12 h. Addition of sodium halide salts strongly increases the reaction rate of copper oxide nanoparticles. The mechanism for the formation of Reactive Oxygen Species (ROS) was investigated by Electron Spin Resonance (ESR).     

A comparative study between two ignition sources: Electric igniter versus pyrotechnic igniter

The risk assessment of combustible explosive dust is based on the determination of the probability of dust dispersion, the identification of potential ignition sources and the evaluation of explosion severity. It is achieved in most of cases with the two main experimental normalized devices such as the Hartmann tube (spark ignition) and the 20 L spherical bomb (with two 5 kJ pyrotechnic ignitors).Ignition energy of the 5 kJ ignitor is well calibrated and generates a reproducible ignition. But, on the other hand, this ignition is not punctual and the over pressure produced is nearly 2 bar. Moreover, the pyrotechnic igniter accelerates the combustion with multi ignition points in a large volume and that disturbs the flame propagation. In this way, this ignition source does not allow to analyze the combustion products because the composition of the pyrotechnic igniter was found in the combustion products.This paper deals with the comparison of two ignition sources in the 20 L spherical bomb. Different explosive dusts of great industrial interest are studied with electrical and pyrotechnic ignitors, in order to understand, first, the influence of each type of igniter on the explosion behaviour and then to evaluate the possibility of establishing a correspondence between parameters obtained with these two ignition sources.Severity parameters of nicotinic acid, aluminium powder and titanium alloy were measured by using the two types of ignition system in our 20 L spherical bomb equipped with the Kühner dihedral injector. The explosion overpressure $\mathrm{P}$ and the rate of pressure rise $\left(\raisebox{1ex}{$dP$}\!\left/ \!\raisebox{-1ex}{$dt$}\right.\right)$ were measured in a large range of concentration allowing to propose correlations between electrical and pyrotechnic ignition for each parameter and each type of powder. These correlations aim to link the tests used with two different collections of experimental parameters for the same dust. The relevance of these correlations will be discussed.