Carbamazepine degradation by heterogeneous activation of peroxymonosulfate with lanthanum cobaltite perovskite: Performance, mechanism and toxicity

The widely used carbamazepine(CBZ) is one of the most persistent pharmaceuticals and suffers insufficient removal efficiency by conventional wastewater treatment.A synthesized Co-based perovskite(LaCoO_3) was used to activate peroxymonosulfate(PMS) in order to degrade CBZ.Results showed that LaCoO_3 exhibited an excellent performance in PMS activation and CBZ degradation at neutral pH,with low cobalt leaching.The results of FT-IR and XPS verified the high structurally and chemically stability of LaCoO_3 in PMS activation.Electron spin resonance(ESR) analysis suggested the generation of radical species,such as sulfate radicals(SO_4·~-) and hydroxyl radicals(·OH).Radical quenching experiments further revealed the responsibility of SO_4·~-as the dominant oxidant for CBZ oxidation.Ten products were detected via the oxidation of CBZ,with the olefinic double bond attacked by SO_4·~-as the initial step.Hydroxylation,hydrolysis,cyclization and dehydration were involved along the transformation of CBZ.The toxicity of CBZ solution was significantly reduced after treating by PMS/LaCoO_3.     

Separating method and dynamic processes of Nano-Al13

In order to investigate the characteristics of pure Nano-Al₁₃, Nano-Al₁₃ was separated and purified from a series of poly-aluminum chloride (PAC) solutions which had the same Al₁₃ percentage but different total Al concentrations, by using column chromatography, ethanol-acetone resolving and SO²⁻ ₄/Ba²⁺ displacement. The Al₁₃ species yield was characterized by Al-ferron timed complexation spectrophotometry and ²⁷Al-NMR (nuclear magnetic resonance). The coagulation efficiency of Nano-Al₁₃, PAC and AlCl₃ in synthetic water was also investigated by Jar tests. The dynamic process and aggregation state of kaolin suspensions coagulating with Nano-Al₁₃, PAC and AlCl₃ were similarly investigated using a photometric dispersion analyzer 2000 (PDA2000). The experimental results indicated that the ethanol-acetone resolving method was simple and could separate the PAC solution at different concentrations, while column chromatography could separate PAC solutions at low concentrations. The SO₄ ²⁻/Ba²⁺ displacement method could separate PAC solutions at high concentrations. However, extra inorganic cation and anion could be added in the solution during separation. The coagulation efficiency and dynamic experimental results showed that Nano-Al₁₃ with high positive-charged species was effective in removing turbidity and color. The dynamic process results showed that Nano-Al₁₃ also had the best recovery capability after shearing compared with PAC and AlCl₃ because the Nano-Al₁₃ conformation is more effective in charge neutralization. Translated from Acta Scientiae Circumstantiae, 2005, 25(6): 767–772 [译自: 环境科学学报]     

漓江风景区环境现状及变化趋势研究

本文根据漓江风景区的水环境、声环境、生态系统和大气环境的现状 ,提出当前存在的主要问题和今后的变化趋势。     

某造纸企业扩建项目环境影响评价工作中清洁生产方案的制定

某造纸企业现有1#～4#生产线在原料储存、工艺技术、设备维护及管理等方面存在较多问题,现拟扩建5#生产线,针对现有工程存在的具体问题及扩建工程原料采用进口木浆的特点,环评制定了1#～4#线集中制浆技改、4#线除渣、1#、4#线节电改造、污水处理站节电改造、可控硅改变频、5#线白水回用等一系列清洁生产方案,并进行可行性分析,给出清洁生产方案实施前后的环境效益对比分析.     

TiO_2太阳能光催化降解有机污染物的研究进展

以太阳能为激发光源的 Ti O2 光催化氧化技术是一项极具运用前景的绿色环保技术。简要介绍了 Ti O2 光催化氧化的原理、催化剂 Ti O2 的制备研究、Ti O2 太阳能反应器的研制以及该项技术在有机污染物降解中的应用     

安徽铜陵鸡冠石银(金)矿床地质地球化学特征

鸡冠石银 (金 )矿床是铜陵地区一个具中型规模的银 (金 )矿床 ,在整个长江中、下游地区都有其代表性。矿床分四个主要成矿阶段 :夕卡岩阶段、氧化物 -硫化物阶段、石英 -硫化物阶段和石英多金属硫化物-碳酸盐阶段。对矿床的微量元素分析结果表明 ,独立的银、金矿物和含Au、Ag低的硫化物、含Ag硫盐矿物 ,主要形成于热液成矿期中晚阶段 ;矿床的轻、重稀土元素总浓度比值与辉石二长闪长岩相近 ,反映出二者的同源特征 ;稳定同位素和流体包裹体成分分析结果 ,反映出该矿床以岩浆热液为主的成因标志 ;成矿热液以岩浆水为主 ,但在成矿晚期有大气降水和地层成分加入 ;成矿流体为NaCl-KCl -H2 O体系 ;矿床成因属夕卡岩 -中低温热液充填 -交代型矿床     

Trophic modification of essential fatty acids by heterotrophic protists and its effects on the fatty acid composition of the copepod Acartia tonsa

To test whether heterotrophic protists modify precursors of long chain n−3 polyunsaturated fatty acids (LCn−3PUFAs) present in the algae they eat, two algae with different fatty acid contents (Rhodomonas salina and Dunaliella tertiolecta) were fed to the heterotrophic protists Oxyrrhis marina Dujardin and Gyrodinium dominans Hulbert. These experiments were conducted in August 2004. Both predators and prey were analyzed for fatty acid composition. To further test the effects of trophic upgrading, the calanoid copepod Acartia tonsa Dana was fed R. salina, D. tertiolecta, or O. marina that had been growing on D. tertiolecta (OM-DT) in March 2005. Our results show that trophic upgrading was species-specific. The presence of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in the heterotrophic protists despite the lack of these fatty acids in the algal prey suggests that protists have the ability to elongate and desaturate 18:3 (n−3), a precursor of LCn−3PUFAs, to EPA and/or DHA. A lower content of these fatty acids was detected in protists that were fed good-quality algae. Feeding experiments with A. tonsa showed that copepods fed D. tertiolecta had a significantly lower content of EPA and DHA than those fed OM-DT. The concentration of EPA was low on both diets, while DHA content was highest in A. tonsa fed R. salina and OM-DT. These results suggest that O. marina was able to trophically upgrade the nutritional quality of the poor-quality alga, and efficiently supplied DHA to the next trophic level. The low amount of EPA in A. tonsa suggests EPA may be catabolized by the copepod.     

利用氧化铝-改性硅胶联柱分离测定水中多氯联苯

本文介绍一种多氯联苯(PCBs)与农药的分离和气相色谱分析PCBs新方法.富集浓缩后的样品首先经浓硫酸酸洗.排除大多数干扰PCBs测定的有机化合物,然后利用氧化铝-硅胶(Ag~+)联柱实现了PCBs和干扰其测定的农药的完全分离,应用毛细管气相色谱分析测试了水样中多氯联苯多种同系物、同分异构体的含量.其方法的回收率在79—88%之间.     

Metabolism of palmitic,linoleic, and linolenic acids in adult oysters,Crassostrea virginica

This study investigated incorporation and metabolism of saturated [(1-¹⁴C) 16:0] and unsaturated [(1-¹⁴C) 18:26 and (1-¹⁴C) 18:33] fatty acids in adult eastern oysters,Crassostrea virginica Gmelin (spawned from parents obtained in 1986 from Mobjack Bay, Virginia, USA), and the influence of temperature on these processes. InC. virginica, incorporation of injected palmitic (16:0) and linolenic (18:33) acids was increased when oysters which had been grown in warm water (22 to 23°C) were transfered to cold water (5 to 7°C) for 8 to 18 d. Incorporation of linoleic acid (18:26) was unchanged under these conditions. The changes in concentration may have been linked to depression of metabolism in these oysters, in particular that of 16:0, which was reduced by 90%. Oxidation of incorporated fatty acids was much higher in warm than in cold water. Cold-temperature conditioning ofC. virginica altered the distribution of fatty acids among the neutral and polar lipid fractions. Long-term exposure to cold water increased the proportion of fatty acids in the polar fraction, which may be related to maintenance of membrane fluidity. Short-term exposure to cold water had the opposite effect, which may be due to increased energy requirements as the oyster adapts to new conditions. Reutilization of¹⁴C-acyl groups demonstrated de novo synthesis of 16:0 and 18:0 fatty acids. Only limited elongation and no desaturation of the administered fatty acids was observed.