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Determination of hexabromocyclododecanes in sediments from the Haihe River in China by an optimized HPLC–MS–MS method

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Journal of Environmental Sciences 2017年第5期29卷 174-183页

作者： Yanhui Zhao Qianqian Li xue miao Xinchen Huang Binke Li Guijin Su Minghui Zheng State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China University of Chinese Academy of Sciences Beijing 100049 China

Hexabromocyclododecanes（HBCDs）,a new type of persistent organic pollutants widely used as brominated flame retardants,have attracted wide attention due to their increasing level and toxicity. A method based on high-performance liquid chromatography mass spectrometry（HPLC–MS–MS）in electrospray ionization mode has been developed by optimization of various parameters,which effectively improved the separation degree and responsive intensity of α-,β-and γ-HBCD isomers. The concentrations and distribution profiles of three HBCD isomers were investigated in sediments from the Haihe River in *** was observed that the concentrations of HBCDs varied in the range of 0.4–58.82 ng/g,showing a decreasing trend along the flow direction,possibly due to attenuation and biodegradation along the flow direction of the Haihe River. The distribution profile of α-,β-,γ-HBCD was 7.91%–88.6%,0–91.47%,and 0.62%–42.83%,respectively. Interestingly,α-HBCD dominated in most sample sites. This was different from the distribution profile in commercial industrial products,which might be attributed to the inter-transformation and different degradation rates of the three HBCD isomers. The potential ecological risk of HBCDs in sediment was characterized under the two-tiered procedure of the European Medicines Evaluation Agency for environmental risk assessment. Although the HBCDs in the selected section of the Haihe River presented ＂no risk＂ in the sediment compartment,its risk in sediment cannot be neglected since sediment is one of the important sinks and reservoirs of pollutants.

关键词： Hexabromocyclododecane HPLC-MS-MS Sediment Haihe River Risk assessment

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Origin of Modulus Improvement for Epoxide-terminated Hyperbranched Poly(ether sulphone)/DGEBA/TETA Systems

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Chinese Journal of Polymer Science 2018年第8期36卷 991-998页

作者： xue-Pei miao Dao-Jian Cheng Ya-Dong Dai Yan Meng Xiao-Yu Li Key Laboratory of Carbon Fiber and Functional Polymers Ministry of Education College of Materials Science and Engineering Beijing University of Chemical Technology Beijing 100029 China State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical Technology Beijing 100029 China Neo Trident Technology Ltd (Beijing) Beijing 100190 China

It has been experimentally shown that epoxide-terminated hyperbranched polyether sulphone （EHBPES） can significantly improve the mechanical properties of traditional diglycidyl ether of bisphenol A/triethylenetetramine （DGEBA/TETA） systems, but the origin of the improvement is still unclear. In this work, we used molecular dynamics （MD） simulations to gain a thorough understanding of the origin of modulus improvement for EHBPES/DGEBA/TETA systems. It is found that the modulus of EHBPES/DGEBA/TETA systems increases with the increase of EHBPES loading. In addition, the crosslinking density, cohesive energy density （CED）, and free volume can be used to understand the modulus for EHBPES/DGEBA/TETA systems. It is shown that the highest modulus is achieved at 7 wt% EHBPES loading due to the highest crosslinking density and CED. When EHBPES loading is below 7 wt%, the higher CED and crosslinking density are responsible for the higher modulus. At higher loadings （〉 7 wt%）, the decreased modulus is closely related to the decreased crosslinking density and increased fractional free volume. It is expected that our results could be of great implications for designing high-performance epoxy materials.

关键词： Modulus Molecular simulation Epoxy resin

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Security Model for Analyzing Data Privacy in Multipath Transport

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China Communications 2012年第5期9卷 32-41页

作者： Song Fei xue miao Zhang Sidong Beijing Jiaotong Univ Sch Elect & Informat Engn Natl Engn Lab Next Generat Internet Interconnect Beijing 100044 Peoples R China

In order to investigate the enhancement of data privacy by distributing data packets via multiple paths, this paper fommlates a security model and analyzes the privacy problem in mul- tipath scenarios leveraging inforrmtion theoretic concept. Based on proposed model, a privacy function related to the path number is discussed. We heuristically recommend the optin^al path num- ber and analyze the tradeoff among the perform- ance, resource consumption and privacy. For re- ducing the inforlmtion leakage, the data schedule algorithms are also proposed. The analytical model can provide guidelines for the multipath protocol design.

关键词： data privacy multipath transport in-formation theory tradeoff

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COPPER(0)-MEDIATED RADICAL POLYMERIZATION OF STYRENE AT ROOM TEMPERATURE

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Chinese Journal of Polymer Science 2013年第4期31卷 702-712页

作者： Xiao-fei Zhang Yang Wu Jun Huang xue-lang miao 张正彪朱秀林 Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application Department of Polymer Science and EngineeringCollege of ChemistryChemical Engineering and Materials ScienceSoochow University

The ＂living＇/controlled radical polymerization （LRP） of styrene （St） at room temperature is rarely reported. In this work, copper（0）（Cu（0））-mediated radical polymerization of St at room temperature was investigated in detail. Dimethyl sulfoxide （DMSO）, N,N-dimethylformamide （DMF） as well as a binary solvent, tetrahydrofuravdl,l,l,3,3,3-hexafluoro-2- propanol were used as the solvents, respectively. Methyl-2-bromopropionate and ethyl 2-bromoisobutyrate were used as the initiators, respectively. The polymerization proceeded smoothly with moderate conversions at room temperature. It was found that DMF was a good solvent with the essential features of LRP, while DMSO was a poor solvent with uncontrollable molecular weights. Besides, the match among the initiator, solvent and molar ratios of reactants can modulate the livingness of the polymerization, and the proper selection of ligand was also crucial to a controlled process. This work provided a first example of Cu（0）-mediated radical polymerization of St at room temperature, which would enrich and strength the LRP technique.

关键词： Gel permeation chromatography (GPC) Kinetics (polym.) Cu(0)-mediated radical polymerization Styrene.

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氟马西尼有关物质的研究与测定

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药学学报 2024年第6期59卷 1765-1772页

作者：缪雪艳杨园陆思思莫金梅黄琳凯韦佳均谷亦平桂林医学院公共卫生学院广西桂林541199 广西环境暴露组学与全生命周期健康重点实验室广西桂林541199 武汉药品医疗器械检验所国家药品监督管理局药物制剂质量研究与控制重点实验室湖北武汉430075

建立高效液相色谱法采用校正因子测定氟马西尼原料中有关杂质。采用Agilent Pursuit XRs C18(250 mm×4.6 mm,5μm)色谱柱,以稀磷酸溶液、甲醇和四氢呋喃为流动相,等度洗脱。采用标准曲线法测定校正因子,通过校正因子计算杂质含量。并... 详细信息

建立高效液相色谱法采用校正因子测定氟马西尼原料中有关杂质。采用Agilent Pursuit XRs C18(250 mm×4.6 mm,5μm)色谱柱,以稀磷酸溶液、甲醇和四氢呋喃为流动相,等度洗脱。采用标准曲线法测定校正因子,通过校正因子计算杂质含量。并用外标法验证校正因子方法的合理性、准确性和可行性。通过强制降解制备含有降解产物的氟马西尼降解溶液;采用LC-MS对降解产生的杂质进行结构确证。结果表明,氟马西尼和各杂质之间均分离良好,杂质A、杂质B、杂质D和杂质E的定量限分别为0.1699、0.3147、0.1439和0.2708 ng,检测限分别为0.0558、0.0969、0.0488和0.0890 ng,质量浓度分别在0.0349~7.8470、0.0387~8.7107、0.0346~7.7941和0.0324~7.2928μg·mL^(-1)内,线性关系良好(n=7)。平均回收率在98.25%~99.42%之间,相对标准偏差(RSD)均小于2.0%(n=9),方法的准确度高。采用外标法和校正因子法测定氟马西尼有关物质,两种方法结果一致。建立的HPLC方法准确度和灵敏度高、重复性好,可用于氟马西尼有关物质的测定。

关键词：氟马西尼校正因子有关物质降解产物高效液相色谱法

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Influence of fuel moisture, charge size, feeding rate and air ventilation conditions on the emissions of PM, OC, EC, parent PAHs, and their derivatives from residential wood combustion

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Journal of Environmental Sciences 2013年第9期25卷 1808-1816页

作者： Guofeng Shen miao xue Siye Wei Yuanchen Chen Qiuyue Zhao Bing Li Haisuo Wu Shu Tao Jiangsu Academy of Environmental Sciences Laboratory of Earth Surface Processes College of Urban and Environmental Sciences Peking University

Controlled combustion experiments were conducted to investigate the influence of fuel charge size, moisture, air ventilation and feeding rate on the emission factors （EFs） of carbonaceous particulate matter, parent polycyclic aromatic hydrocarbons （pPAHs） and their derivatives from residential wood combustion in a typical brick cooking stove. Measured EFs were found to be independent of fuel charge size, but increased with increasing fuel moisture. Pollution emissions from the normal burning under an adequate air supply condition were the lowest for most pollutants, while more pollutants were emitted when an oxygen deficient atmosphere was formed in the stove chamber during fast burning. The impacts of these factors on the size distribution of emitted particles was also studied. Modified combustion efficiency and the four investigated factors explained 68%, 72%, and 64% of total variations in EFs of PM, organic carbon, and oxygenated PAHs, respectively, but only 36%, 38% and 42% of the total variations in EFs of elemental carbon, pPAHs and nitro-PAHs, respectively.

关键词： residential wood combustion influencing factor carbonaceous particulate matter polycyclic aromatic hydrocarbons emission factor

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Boosting ammonia production in electrocatalytic NO_(x)reduction on a robust Fe/FeMoO_(4)catalyst

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Nano Research 2024年第7期17卷 5801-5806页

作者： Dong-xue Liu Xin Deng Yong-Fu Zhu Zhe Meng xue-Feng Sun miao-miao Shi Hai-Xia Zhong Jun-Min Yan Key Laboratory of Automobile Materials Ministry of EducationSchool of Materials Science and EngineeringJilin UniversityChangchun 130022China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

Electrocatalytic reduction of nitrate(NO_(3)^(−))and nitride(NO_(2)^(−))to ammonia(NH3)is of wide interest as a promising alternative to the energy-intensive Haber-Bosch route for mitigating the vast energy consumption and the accompanied carbon dioxide emission,as well as benefiting for the relevant sewage ***,exploring an efficient and low-cost catalyst with high atomic utilization that can effectively facilitate the slow multi-electron transfer process remains a grand ***,we present an efficient hydrogenation of NO_(3)^(−)/NO_(2)^(−)species to NH3 in both alkaline and neutral environments over the Fe_(2)(MoO_(4))_(3)derived hybrid electrocatalyst with the metallic Fe site on FeMoO_(4)(Fe/FeMoO_(4)).The Mo ingredient can play a synergistically positive role in further promoting the NH_(3) production on *** a result,Fe/FeMoO_(4)behaves well in the electrochemical NH_(3) generation from NO_(2)^(−)with a maximum NH_(3) Faradaic efficiency(FE)of 96.53%and 87.68%in alkaline and neutral electrolyte,corresponding to the NH_(3) yield rate of 640.68 and 302.56 mg·h^(−1)·mg_(cat.)^(−1),respectively,which outperforms the Fe and Mo counterpart and other similar catalyst,showing the robust catalytic capacity of each active site.

关键词： ammonia synthesis NO_(x)reduction synergistic effect alkaline/neutral electrolyte

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职业本科大数据与会计专业人才培养“达本”路径与实践

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承德石油高等专科学校学报 2024年第4期26卷 5-10页

作者：丁丽娜张海峰苗学凤刘进河北石油职业技术大学河北承德067000 承德永峰会计师事务所河北承德067000 日照市城市建设投资集团有限公司山东日照276800

人才培养质量“达本”是现阶段职业本科大数据与会计专业人才培养面临的中心任务。对当前职业本科大数据与会计专业面临的优势和挑战进行了分析,进而对规格定位、课程体系及教学实施进行了探讨,认为应将“业务高端”和“财务高端”作为... 详细信息

人才培养质量“达本”是现阶段职业本科大数据与会计专业人才培养面临的中心任务。对当前职业本科大数据与会计专业面临的优势和挑战进行了分析,进而对规格定位、课程体系及教学实施进行了探讨,认为应将“业务高端”和“财务高端”作为规格标准;应强调“人”与“职业”并育,“岗课赛证”协同,技术技能全过程贯通;要切实调整教学组织管理制度,设置适合技术技能型人才培养需要的学时学分要求,全面提高“双师型”师资队伍质量,严格制定毕业标准,适度追求一次就业率,以保证人才培养质量跃升至本科层次,达到职业本科专业办学的质量要求。

关键词：职业本科大数据与会计人才培养质量规格定位

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Effect of Candesartan Cilexetil as a Sensitive and Effective Inhibitor of SHP-1 on Insulin Signaling Pathway

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Chemical Research in Chinese Universities 2013年第4期29卷 730-734页

作者： ZHANG Lei ZHANG Shi-tao ZHANG Xiao-ping SUN Jing WANG Yong-sen LIU Yue-long xue miao-miao WANG Zhi XING Shu MA Jun-feng LI Wan-nan FU xue-qi Key Laboratory for Molecular Enzymology and Engineering Ministry of Education Jilin University Changchun 130012 P. R. China Clinical Laboratory China-Japan Union Hospital Jilin University Changchun 130033 P. R. China State Engineering Laboratory of A1DS Vaccine Jilin University Changchun 130012 R. P. China

The protein tyrosine phosphatases（PTPs） comprise a family of enzymes that specifically dephosphorylate tyrosyl residues. Among them, SHP-I has been regarded as one of the best validated intracellular tyrosine phospha- tases. Downregulation of SHP-1 has shown remarkable efficacy in improving insulin sensitivity in vivo in insulin signaling pathway. In this study, we found the role of Candesartan cilexetil targeting at SHP-1. The results indicate that Candesartan cilexetil was a competitive inhibitor to SHP-1（IC50=85.6 ~tmol/L and Ki=24 ~tmol/L）. We also found that Candesartan cilexetil was more sensitive towards SHP-1 compared with other PTPs. Through the consequence of Western blotting, it showed that Candesartan cilexetil can strengthen the level of tyrosine phosphorylation of several key cellular proteins[such as insulin receptor（IR）, insulin receptor substrate（IRS） and ERK] in insulin signaling pathway in HepG2 cells and improve the insulin sensitivity through inhibiting the protein phosphorylation of SHP-1. These findings showed that Candesartan cilexetil might be an important inhibitor of SHP-1 and had a great applica- tion potential in the treatment of diabetes through inhibiting the level of SHP-1 in insulin signaling pathway.

关键词： SHP-1 Candesartan cilexetil Inhibitor Insulin sensitivity

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An improved association-mining research for exploring Chinese herbal property theory: based on data of the Shennong's Classic of Materia Medica

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Journal of Integrative Medicine 2013年第5期11卷 352-365页

作者： Rui Jin Zhi-jian Lin Chun-miao xue Bing Zhang Department of Pharmacy Beijing Shijitan Hospital School of Chinese Materia Medica Beijing University of Chinese Medicine

Knowledge Discovery in Databases is gaining attention and raising new hopes for traditional Chinese medicine （TCM） researchers. It is a useful tool in understanding and deciphering TCM theories. Aiming for a better understanding of Chinese herbal property theory （CHPT）, this paper performed an improved association rule learning to analyze semistructured text in the book entitled Shennong＇s Classic of Materia Medica. The text was firstly annotated and transformed to well-structured multidimensional data. Subsequently, an Apriori algorithm was employed for producing association rules after the sensitivity analysis of parameters. From the confirmed 120 resulting rules that described the intrinsic relationships between herbal property （qi, flavor and their combinations） and herbal efficacy, two novel fundamental principles underlying CHPT were acquired and further elucidated：（1） the many-to-one mapping of herbal efficacy to herbal property; （2） the nonrandom overlap between the related efficacy of qi and flavor. This work provided an innovative knowledge about CHPT, which would be helpful for its modern research.

关键词： traditional Chinese medicine Chinese herbal property theory association rulelearning knowledge discovery data mining

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