利用磷霉素生产盐渣合成阻垢剂

将磷霉素生产盐渣经水解得到右旋磷霉素二钠,再通过亲核取代反应得到可用作循环冷却水阻垢剂的氨基二乙基(1-甲基-2-羟基)膦酸四钠(ADMHP·Na4),并用FTIR表征了产物结构.实验结果表明:在取代反应温度为25℃、取代反应时间为2h、n(氨水)∶n(右旋磷霉素二钠)=8的条件下,由右旋磷霉素二钠制备ADMHP·Na4,收率可达83.87％.处理1t盐渣可创造利润3 080元.当ADMHP·Na4质量浓度为30 mg/L,水样温度为60℃时,ADMHP·Na4对CaCO3的阻垢效果较好,阻垢率可达91.47％.     

Molecular cloning, characterization of CAT, and eco-toxicological effects of dietary zinc oxide on antioxidant enzymes in Eisenia fetida

The full-length cDNA of catalase (EfCAT) from Eisenia fetida was cloned (GenBank accession no. JN617999). Sequence characterization revealed that EfCAT protein sequence contained proximal heme-ligand signature sequence (³⁵¹RLFSYSDTH³⁵⁹), two glycosylation sites (N₁₄₅ and N₄₃₆), the proximal active site signature (⁶¹FDRERIPERVVHAKGAGA⁷⁸), and 12 amino acids (N₁₄₅, H₁₉₁, F₁₉₅, S₁₉₈, R₂₀₀, N₂₁₀, Y₂₁₂, K₂₃₄, I₂₉₉, W₃₀₀, Q₃₀₂, and Y₃₅₅), which were identified as putative residues involved in NADPH binding. These conserved motifs and catalase signature sequences were essential for the structure and function of EfCAT. The present study also investigated the effect of the veterinary food additive zinc oxide on antioxidant processes in E. fetida, at different concentrations and exposure durations. A significant increase (by 106.0 % compared to controls) in CAT activity at 500 mg/kg was registered at day 15. The superoxide dismutase (SOD) activity at 500 mg/kg increased to the maximum value (by 44.0 %) measured at day 15. There was a significant increase in glutathione peroxidase (GPx) activity for all concentrations after 5 days. The results showed that dietary Zn (500 mg/kg) causes oxidative damage to earthworms. At early stages of earthworms exposed to ZnO, GPx is the main enzyme to impair the oxidative status; while at later stages the enzymes CAT and SOD were the main indicators of oxidative stress. The antioxidant enzymatic variations may be an adaptive response of earthworms to survive in contaminated soils.     

Recycling of valuable chemicals through the catalytic decomposition of phenol tar in cumene process

The base catalyst LZ-2, which was the mixture of CaO and Na–NaOH/Al₂O₃·3H₂O, was chosen for the decomposition of phenol tar to generate valuable chemicals. The selectivity of LZ-2 for dimethyl phenyl carbinol, α-methyl styrene dimer and cumenyl phenol was 100%, 100% and 98%, respectively. Under the optimum operating conditions of catalyst 2.5 wt%, operating temperature 603.15 K and decomposition time 3.5 h, decomposition ratios of cumenyl phenol and dimethyl phenyl carbinol were 98.7% and 99.97%, respectively. In addition, the experimental repeatability demonstrated that the total yield of valuable chemicals still reached 90.1% after the catalyst being used five times. Mass and energy balance indicated that the catalytic decomposition was a high potential for the recycling of chemicals from phenol tar.     

The electrochemical selective reduction of NO using CoSe2@CNTs hybrid

Converting the NO from gaseous pollutant into NH₄ ⁺ through electrocatalytical reduction using cost-effective materials holds great promise for pollutant purifying and resources recycling. In this work, we developed a highly selective and stable catalyst CoSe₂ nanoparticle hybridized with carbon nanotubes (CoSe₂@CNTs). The CoSe₂@CNTs hybrid catalysts performed an extraordinary high selectivity for NH₄ ⁺ formation in NO electroreduction with minimal N₂O production and H₂ evolution. The specific spatial structure of CoSe₂ is conductive to the predominant formation of N-H bond between the N from adsorbed NO and H and inhibition of N-N formation from adjacent adsorbed NO. It was also the first time to convert the coordinated NO into NH₄ ⁺ using non-noble metal catalysis. Moreover, the original concept of employing CoSe₂ as eletrocatalyst for NO hydrogenation presented in this work can broaden horizons and provide new dimensions in the design of new highly efficient catalysts for NH₄ ⁺ synthesis in aqueous solution.

     

Economic Valuation of Health Impact of PM10 Pollution in Beijing from 2001 to 2006

Abstract

In light of the practical need for research to inform policy in Beijing, this study evaluates the economic cost of the impact of PM₁₀ pollution in Beijing from 2001 to 2006, taking health as the main impact, and mortality as the main outcome. Based on the literature review, this study adopts relatively conservative parameters as the basis for calculating the health impacts. It concludes that nearly 30% of mortality among registered residents above age 30 in Beijing can be attributed to PM₁₀ pollution, and that the economic cost equals 0.8%–1.2% of the city’s GDP over the same period. This is lower than the results of previous studies, but still high enough to warrant a commitment to solve the city’s air pollution problem.     

济钢中板厂精整区噪声污染的分析与对策

分析了济钢中板厂精整区噪声污染严重的原因。采取了吸音材抖、消声设备、加强个体防护等措施,使总声压级由105dB降到72dB,保护了职工的身体健康。     

On some studies about the dynamic mechanisms of carbon monoxide flow and diffusion during high energy gas fracturing

High energy gas fracturing (HEGF) technique has been one of central stimulating measures to enhance oil recovery in low permeability reservoirs. But, in recently few years, some serious CO poisoning accidents took place in oilfields here in China. It is very important to reveal the dynamic mechanisms of carbon monoxide flow and diffusion to operating safety during high energy gas fracturing. In this paper, some dynamic mechanisms of carbon monoxide CO flowing inside a oil wellbore and diffusion on the top of the well during high energy gas fracturing were studied with fluid/gas hydrodynamics. The CO flow model within a wellbore and the diffusion model in air were established. The key factors affecting CO flow and diffusion such as wellbore pressure, gas-oil ratio, wind speed, leakage speed, air-permanence were inspected with mathematical simulation. It will be of significance to provide an important guidance for monitoring and preventing CO poisoning accidents during high energy gas fracturing.     

3种不同功效医药品活性成分对发光菌的毒性作用

因药物活性成分的环境残留引发的风险和健康问题成为公众关注的焦点。本文以海洋发光细菌为受试生物,研究了布洛芬、阿奇霉素、三氯生3种医药品的单一和联合毒性作用。结果表明,3种医药品对发光菌的EC_(50)值分别为:36.5×10~(-5)、30.26×10~(-5)和0.0155×10~(-5)mol·L~(-1);二元及多元混合体系对发光菌的EC_(50)值高于单一体系的毒性作用,进一步采用相加指数法(AI)、毒性单位法(TU)、混合毒性指数法(MTI)评价3种医药品多元体系的联合毒性的作用类型,取得了一致的评价结果。3种医药品的二元混合体系及多元混合体系的作用类型均属于拮抗作用,但拮抗作用的强弱不同,这与医药品不同药效官能团结构可影响其对微生物生理生化反应过程有关。研究3种医药品对发光菌急性毒性作用可为该类新型污染物的环境风险评价提供基础数据。     

黄土高原发展与生态改善

“陇中之苦,甲于天下”。这是黄土高原对甘肃定西地区和宁夏的西吉、海原、固原(西海固)的历史性结论。政府和国际援助多年来的努力使这一带的贫困状况有所减轻。但是至今这种状况仍然没有全部改观,特别是在远离城市和道路的深山。“三西”依然是中国最贫困的地区。究其原因,降水少而干旱,是生产效率低下的主因。频繁的旱灾往往使粮食绝收,人畜干渴而死;而夏秋集中的豪雨及多发的冰雹,又往往毁坏农作物和冲毁田地。