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Comparison of Pb and Cd adsorption to the surface coatings and surficial sediments collected in Xianghai Wetland

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Journal of Environmental Sciences 2005年第1期17卷 126-129页

作者： LIYu WANGXiao-li WANGYue DONGDe-ming ZHANGHua-peng liqing-shan LIXingchun CollegeofEnvironmentandResources JilinUniversityChangchun130023China Song-LiaoRiverBasinWaterResourcesProtectionBureau Changchun130021China CollegeofEnvironmentandResources JilinUniversityChangchun130023China／／Song-LiaoRiverBasinWaterResourcesProtectionBureauChangchun130021China

Surface coatings and surficial sediments were obtained in four natural waters in Xianghai Wetland in China to study the role of surface coatings and surficial sediments in controlling the transporting and cycling of heavy metals in aquatic environments. Pb and Cd adsorption to the surface coatings and surficial sediments were measured under controlled laboratory conditions(mineral salts solution with defined speciation, ionic strength 0 05 mol/L, 25℃ and pH 6 0 for surface coatings; and 0 005 mol/L CaCl 2 solution, 25℃ and pH 6 0 for surficial sediments). The Langmuir adsorption isotherm was applied to estimate equilibrium coefficients of Pb and Cd adsorption to the surface coatings and surficial sediments, and the component analyses of surface coatings and surficial sediments were also carried out. Correlation analyses between the maximum adsorption of Pb and Cd(Г max ) and the components in the surface coatings and surficial sediments suggested that there was a statistically significant trend for Pb and Cd adsorption(Г max ) to the surface coatings to increase with increasing in contents of Fe and Mn oxides in the surface coatings and surficial sediments. And the metal adsorption abilities of surface coatings were much stronger than those of surficial sediments, highlighting that in the same water, i.e. at the same pH and initial metal concentrations, the metals(such as lead and cadmium) in supernatant were feasible to be adsorbed by surface coatings than surficial sediments. The more importance of surface coatings than surficial sediments for adsorbing and cycling of heavy metals in aquatic environments was evidenced.

关键词： surface coatings surficial sediments Pb Cd adsorption capabilities

Purification and Characterization of PRL Protein Tyrosine Phosphatases

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Chemical Research in Chinese Universities 2005年第3期21卷 294-297页

作者： LIZhao-fa WANGYan liqing-shan ZHAOZhi-zhuangJoe FUXue-qi LIYu-lin LIYi-lei EdmondH.FischerSignalTransductionLaboratory CollegeofLifeScienceslilinUniversityChangchun130023P.R.China TheKeyLaboratoryofPathobiologyofEducationalMinistry JilinUniversityChangchun130023P.R.China

PRLs constitute a subfamily of protein tyrosine phosphatases(PTPs). In the present paper are reported the molecular cloning, expression, purification, and characterization of all the three members of the PRL enzymes in human and the only PRL in ***. These enzymes were expressed as glutathione S-transferase(GST) fusion proteins in DE3pLysS *** cells, and the recombinant fusion proteins were purified on glutathione-Sepharose affinity columns. Having been cleaved with thrombin, GST-free enzymes were further purified on an S-100 Sepharose gel filtration column. The purified proteins show single polypeptide bands on SDS-polyacrylamide gel electrophoresis. With para-nitrophenyl phosphate(p-NPP) as a substrate, PRLs exhibit classical Michaelis-Menten kinetics with V_~max values two orders of magnitude smaller than those of classic PTPs. The responses of PRLs to ionic strength, metal ions and phosphatase inhibitors are similar to those of other characterized PTPs, but their optimal pH values are different. These data thus reveal distinct common biochemical properties of PRL subfamily PTPs as well.

关键词： PTP PRL Purification Characterization

Influences of laser energy density and annealing on structure properties of AlN films prepared by pulsed laser deposition

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Optoelectronics Letters 2007年第4期3卷 286-288页

作者： Lu Lei liqing-shan LiLi ZHANGLi-chun WANGCai-feng QlHong-xia ZHENGMeng-meng CollegeofPhysicsandEngineering QufuNormalUniversityQufu273165China LudongUniversity Yantai264025China LaserInstituteofQufuNormalUniversity Qufu273165China

Aluminum nitride （AlN） films with h〈100〉 crystalline orientation are fabricated on p-Si （100） substrates at room tempera- ture by pulsed laser deposition. The effects of laser energy density and annealing on the quality of the films are studied by x-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy. The crystalline quality of AlN films is improved considerably by increasing the laser energy density while there is increased number of farraginous particles on the surface. The annealing treatment at 600~C produces a recrystallization process in the film, characterized by the improvement of the original crystallinity, the appearance of new crystalline orientations, and the increase of the crystallites. The surface becomes rougher due to the increase of the grain size during annealing.

关键词：激光薄膜沉积作用能量密度

“因改善而消亡”:标准化建设与农村小规模学校生存困境——基于县域义务教育均衡政策的实践案例

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中国农业大学学报（社会科学版） 2019年第4期36卷 33-42页

作者：单丽卿杭州师范大学公共管理学院杭州师范大学社会建设和社会治理研究中心

在推进县域义务教育均衡发展的背景下,农村学校的办学条件不断改善,但是与此相伴随的却是村级学校数量的持续减少。文章试图对这种"因改善而消亡"的现象做出解释,通过对中央政策和县域实践的考察,揭示教育均衡政策与农村小规模学校生存... 详细信息

在推进县域义务教育均衡发展的背景下,农村学校的办学条件不断改善,但是与此相伴随的却是村级学校数量的持续减少。文章试图对这种"因改善而消亡"的现象做出解释,通过对中央政策和县域实践的考察,揭示教育均衡政策与农村小规模学校生存困境之间的关联。在县域的政策实践中,标准化建设成为推动义务教育均衡发展的主要路径,自上而下的考核压力强化了县级政府在政策执行中的"目标替代",产生了政策扭曲,其结果是村级学校的局部改善与整体边缘化,在客观上加剧了农村小规模学校的生存危机。文章对教育发展政策中的"硬件偏好"与"投入导向"作出反思,引入教育生态的概念,强调树立整体性的政策观,以重建教育生态为核心政策目标,推动农村小规模学校整体发展环境的实质性改善。

关键词：标准化建设均衡发展学校布局调整教育生态

Multidisciplinary treatment of molten aluminum combined burn:An unusual case report

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Chinese Journal of Plastic and Reconstructive Surgery 2024年第3期6卷 135-138页

作者： Shengzhou shan Yinbo Peng liqing Gong Zhigang Mao Weirong Yu Tao Ni Peng Xu Department of Plastic and Reconstructive Surgery Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghai200011China

Molten aluminum is among the most common causes of burns in the metal ***,only few reports are available on molten aluminum ***,we report an unusual case of molten aluminum *** patient had burns not only on the body surface but also in the respiratory tract and esophagus,adding to the difficulty of *** consultation and cooperation led to the development of a treatment plan for the patient,which included tracheotomy,respiratory management,endoscopic therapy,infection control,and psychological *** our knowledge,this is the first report of molten aluminum-induced burns involving the face,neck,respiratory tract,esophagus,and *** also describe our experience with multidisciplinary treatment for the management of molten aluminum burns.

关键词： Molten aluminum Combined burn Multidisciplinary treatment

农村产业发展中的“小农境地”与国家困局——基于西部某贫困村产业扶贫实践的社会学分析

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中国农业大学学报（社会科学版） 2018年第3期35卷 38-47页

作者：王春光单丽卿中国社会科学院社会学所杭州师范大学政治与社会学院

农村产业扶贫政策作为国家在贫困地区推动农业现代化的具体实践,核心是在农业生产层面对小农逻辑进行全面改造,即从"为生存而生产"向"为市场而生产"转型。但是,旨在"帮助小农户对接市场"的产业扶贫政策,并不能达成令人满意的预期效果,... 详细信息

农村产业扶贫政策作为国家在贫困地区推动农业现代化的具体实践,核心是在农业生产层面对小农逻辑进行全面改造,即从"为生存而生产"向"为市场而生产"转型。但是,旨在"帮助小农户对接市场"的产业扶贫政策,并不能达成令人满意的预期效果,乃至遭遇失败,产生了"小农境地"。本研究对一个贫困村的产业扶贫实践进行了历时和共时的分析,揭示了为何政策实践会陷入"动员—失败—再动员"的困境,讨论了相关政策的合理性和有效性;围绕"国家、农民和市场"关系,通过对产业扶贫政策的反思,发现国家在"改造农民"和"驾驭市场"方面面临的双重困境,原因在于政策定位和聚焦不合理。由此本文提出了产业扶贫政策应该进行"服务转向"。

关键词：产业扶贫回应商品化风险管理

Stormwater runoff pollution loads from an urban catchment with rainy climate in China

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Frontiers of Environmental Science & Engineering 2012年第5期6卷 672-677页

作者： liqing LI Baoqing shan Chenqing YIN School of Environmental Studies China University of GeosciencesWuhan 430074China SKLAC Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

An older urban district in Wuhan, China, is transitioning from discharging sewage and stormwater directly into lakes, to directing the sewage to wastewater treatment plants （WWTPs）. Dealing with polluted storm- water discharge is a great challenge. Stormwater runoff from an urban catchment with a combined sewer system was sampled and analyzed over a three-year period. Results indicate that wet weather flows account for 66%, 31%, 17%, and 13 % of the total load of suspended solids （SS）, chemical oxygen demand （COD）, total nitrogen, and total phosphorus, respectively. The first flush of COD and SS was significant in all runoff events. More than 50% of the SS and COD loads were transported by the first 30% of runoff volume. Storage and treatment of the first 10 mm from each combined sewer overflow event could reduce more than 70% of the annual COD overflow load. An integrated solution is recommended, consisting of a tank connected to the WWTP and a detention pond, to store and treat the combined sewer overflow （CSO）. These results may be helpful in mitigating CSO pollution for many other urban areas in China and other developing countries.

关键词： combined sewer overflow pollution load firstflush detention basins

超高效液相色谱-串联质谱法检测乳清蛋白粉中神经节苷脂GD3

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中国乳品工业 2024年第1期52卷 53-58页

作者：宋戈苗晶孙立庆高珊徐慧许瑞敏李筱薇黑龙江省绿色食品科学研究院哈尔滨150028 美赞臣婴幼儿营养品研发中心有限公司广州510000

建立了超高效液相色谱-串联质谱快速测定乳清蛋白中双唾液酸神经节苷脂(GD3)的方法。通过试验优化样品的初次提取条件(提取剂比例及用量)和再萃取条件(萃取剂用量)。在样品充分溶解后,用4 mL三氯甲烷-甲醇溶液(V_(三氯甲烷)∶V_(甲醇溶... 详细信息

建立了超高效液相色谱-串联质谱快速测定乳清蛋白中双唾液酸神经节苷脂(GD3)的方法。通过试验优化样品的初次提取条件(提取剂比例及用量)和再萃取条件(萃取剂用量)。在样品充分溶解后,用4 mL三氯甲烷-甲醇溶液(V_(三氯甲烷)∶V_(甲醇溶液)=1∶2)提取1.0 mL样液,转移合并提取液,加入2.0 mL水进行萃取转移为最佳提取条件。然后分别对质谱与色谱条件(定量扫描模式、色谱柱以及流动相pH)进行优化,选取Syncronis HILIC硅胶色谱柱,以0.01 mol/L乙酸铵水溶液-乙腈(pH5.6)为流动相,进行色谱分离,色谱分离后采用母离子监测模式定量测定和多反应监测模式定性分析。在最佳优化分析条件下,双唾液酸神经节苷脂GD3质量浓度在0.5~50.0μg/mL内具有良好的线性关系,相关系数(R^(2))>0.99,回收率在87.3%~103.7%,精密度(RSD)为4.16%~8.95%,检出限在0.1 g/kg。该方法可用于乳清蛋白粉中双唾液酸神经节苷脂GD3。

关键词：双唾液酸神经节苷脂GD3 母离子扫描乳清蛋白超高效液相色谱-串联质谱

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依折麦布的合成工艺改进

化学与生物工程 2018年第6期35卷 42-47页

作者：贺凯王光杰王润芝李庆山徐凤波南开大学化学学院元素有机化学国家重点实验室天津300071

依折麦布是唯一的胆固醇吸收抑制剂。对3条依折麦布合成路线进行比较分析后,选择了一条反应步骤较短、条件较温和且处理较简单的合成路线,通过核磁共振氢谱和碳谱对中间体进行了表征,并对反应中间体的合成工艺进行了优化,不仅降低了成... 详细信息

依折麦布是唯一的胆固醇吸收抑制剂。对3条依折麦布合成路线进行比较分析后,选择了一条反应步骤较短、条件较温和且处理较简单的合成路线,通过核磁共振氢谱和碳谱对中间体进行了表征,并对反应中间体的合成工艺进行了优化,不仅降低了成本而且提高了收率。

关键词：依折麦布合成工艺改进胆固醇抑制剂