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Topsoil dichlorodiphenyltrichloroethane and polychlorinated biphenyl concentrations and sources along an urban-rural gradient in the Yellow River Delta

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Journal of Environmental Sciences 2012年第9期24卷 1655-1661页

作者： wenjun Xie Aiping Chen Jianyong li qing liu Hongjun Yang Tao Wu Zhaohua Lu Shandong Key Laboratory of Eco-Environmental Science for the Yellow River Delta Binzhou University Binzhou 256603 China. Institute of Restoration Ecology China University of Mining and Technology Beijing 100083 China Jinan Entry-Exit Inspection and Quarantine Bureau Jinan 250000 China

The Yellow River Delta （YRD） is a typical agricultural and petrochemical industrial area of China. To assess the current status of soil dichlorodiphenyltrichloroethane （DDT） and polychlorinated biphenyls （PCB） residues, topsoil samples （0-15 cm）（n = 82） were collected in Bincheng District, at the geographic center of the YRD. The total concentrations of six DDT homologues were within 3.3-3819 ~tg/kg, with a mean concentration of 191 ~tg/kg, showing significant increase along urban-rural gradient. Soil concentrations of seven indicator PCBs in the area ranged from non-detectable to 87.0 ~g/kg, dominated by heavily chlorinated PCBs （PCB-101 and -118）. Soil PCBs concentrations were significantly greater in urban than suburban and rural areas. Principal component and multiple linear regression analysis suggest that 86.4% of soil DDTs originate from past DDT usage, and 13.6% originate from dicofol application. Soil PCBs most likely originate from the petrochemical industry （77.1%）, municipal solid waste disposal （16.5%）, local commercial PCB homologues usage （5.2%）, and long-range atmospheric deposition （1.2%）. In general, soil DDTs pollution was classified as low level, and mean PCBs concentrations were below the severe contamination classification range. Because PCB-118 is a dioxin-like congener, monitoring and remediation is advised to assess and reduce negative environmental and human health effects from soil DDTs and dioxin-like congeners in the study area.

关键词： DDTs PCBs Yellow River Delta source apportionment risk assessment

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Dynamics of quantum zeno and anti-zeno efects in an open system

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Science China(Physics,Mechanics & Astronomy) 2014年第2期57卷 194-207页

作者： ZHANG Peng AI qing li Yong XU DaZhi SUN ChangPu Department of Physics Renmin University of China Department of Chemistry and Center for Quantum Science and Engineering National Taiwan University Beijing Computational Science Research Center Institute of Theoretical Physics Chinese Academy of Sciences

We provide a general dynamical approach for the quantum Zeno and anti-Zeno effects in an open quantum system under repeated non-demolition measurements. In our approach the repeated measurements are described by a general dynamical model without the wave function collapse postulation. Based on that model, we further study both the short-time and long-time evolutions of the open quantum system under repeated non-demolition measurements, and derive the measurement-modified decay rates of the excited state. In the cases with frequent ideal measurements at zero-temperature, we re-obtain the same decay rate as that from the wave function collapse postulation （Nature, 2000, 405： 546）. The correction to the ideal decay rate is also obtained under the non-ideal measurements. Especially, we find that the quantum Zeno and anti-Zeno effects are possibly enhanced by the non-ideal natures of measurements. For the open system under measurements with arbitrary period, we generally derive the rate equation for the long-time evolution for the cases with arbitrary temperature and noise spectrum, and show that in the long-time evolution the noise spectrum is effectively tuned by the repeated measurements. Our approach is also able to describe the quantum Zeno and anti-Zeno effects given by the phase modulation pulses, as well as the relevant quantum control schemes.

关键词： quantum Zeno effect quantum anti-Zeno effect quantum measurement

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Expressed sequence tags (ESTs) analysis of the ripening Vitis amurensis cv. Shuang Hong berry skins

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Journal of Forestry Research 2013年第3期24卷 495-502页

作者： JI Xiang-Nan li Feng YANG Cheng-Jun li Bo WANG Jun ZHANG wen Center for Viticulture and Enology College of Food Science & Nutritional Engineering China Agricultural University College of Forestry Northeast Forestry University College of Agriculture & Biotechnology China Agricultural University

Vitis amurensis is a valuable resource for wine production. Ripening of the grape berry is the key phase which determines the com- position of wine. To better understand the gene expression that manifest in V. amurensis berry skins during the ripening, cDNA library of V. amurensis berry skins was constructed. A total of 935 high quality ex- pressed sequence tags （ESTs） were obtained from the library. These ESTs represent 636 unigenes, including 108 contigs and 528 singletons. The EST analysis was performed and genes were assigned to functional categories according to their primary BLAST match. Of these 25.35% were involved with metabolism, 6.27% with cell rescue and defense, 6.84% energy, 11.68% protein synthesis, 18.8% protein activity regula- tion, 11.11% cell structure, 7.98% transport, 6.27% transcription and the remaining 5.7% were signal transduction. The generated ESTs were characterized by the gene ontology analysis and were categorized ac- cording to its cellular component, molecular function and biological process. In the cDNA library, some genes are relevant to the biosynthesis of anthocyanins, while some genes are related to grape berry maturation.

关键词： Vitis amurensis expressed sequence tags (ESTs) cDNAlibrary unigene annotation gene ontology

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Random Copolymers Based on Thieno[3,4-c]pyrrole-4,6-dione and Isoindigo Building Blocks for Polymer Solar Cells

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Chinese Journal of Chemistry 2014年第6期32卷 521-526页

作者： Ping Deng Jian Xiong Shugang li Yibing Wu Junliang Yang qing Zhang School of Chemistry and Chemical Engineering Shanghai Jiao Tong UniversityShanghai 200240China Institute of Super Microstructure and Ultrafast Process in Advanced Materials School of Physics and ElectronicsCentral South UniversityChangshaHunan 410083China

Three random conjugated polymers,RP-TiI,RP-2TiI and RP-TVTiI based on both thieno[3,4-c]pyrrole-4,6-dione and isoindigo units have been synthesized by Stille cross-coupling *** optical and electrochemical properties of new polymers have been *** resulted polymers showed broad absorption spectra and appropriate energy levels for polymer solar cell *** bulk heterojunction devices based on the blend of the polymer RP-TiI and PC_(61)BM showed a power conversion efficiency of 1.75%.

关键词： thieno[3,4-c]pyrrole-4 6-dione isoindigo random copolymers polymer solar cells

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Mo@PANI-catalyzed oxidative deoximation reaction

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Chinese Chemical Letters 2024年第2期35卷 407-410页

作者： Yiyang Zhang wen li Zuofeng Hu Xiaobi Jing Lei Yu School of Mechanical Engineering Yangzhou UniversityYangzhou 225127China School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China Yangzhou Yangzi Auto Interior & Exterior Co. Ltd.Yangzhou 225119China

Deoximation is an important transformation in synthetic *** can be employed in protection,characterization and purification of the carbonyls,and in the synthesis of ketones from non-carbonyl *** the field,oxidative deoximation reaction can utilize the driving force caused by the oxidation process so that the reaction can occur under relatively mild ***,we designed and prepared polyaniline-supported molybdenum(Mo@PANI)just by immersing PANI into the EtOH/H_(2)O solution of MoCl_(5).The material was successfully applied as the efficient catalyst for oxidative deoximation reactions,which were performed in ethanol using H_(2)O_(2)as the clean *** substrate scope of the reaction was *** could be applied on heterocycle-containing substrates,making this protocol preferable for pharmaceutical intermediate *** Mo is a necessary trace element for both animals and plants,this method is environment-friendly and is suitable for large-scale *** work as the first example of Mo-catalyzed oxidative deoximation reaction may inspire novel ideas for both catalyst design and synthetic process development.

关键词： Molybdenum Polyaniline Oxidation Deoximation Carbonyl

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Photoregulation of protein plasmid expression in vitro and in vivo using BHQ caging group

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Chinese Chemical Letters 2011年第3期22卷 338-341页

作者： Zhi Ping Zhang Ming li Xiao Yun Chen qing Xiang Guo Department of Chemistry University of Science and Technology of China Hpfei 230026 China Department of Chemistry Tsinghua University Beijing 100084 China

Green fluorescent protein（GFP） plasmid was caged by 8-bromo-7-hydroxyquinolinyl chromophore（BHQ） for controlling its expression with exact spatiotemporal *** vitro and in vivo experiments clearly verified that,comparing with Bhc caging, the expression level of caged GFP plasmid was dramatically decreased and then efficiently restored after subsequent photolysis.

关键词： Photoregulation Caging(uncaging) BHQ Green fluorescent protein plasmid Photolysis

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STUDIES ON CARBOHYDRATES *** STEREOSELECTIVE SYNTHESIS OF 1-O-α-ACYL-D-MANNOPYRANOSE FROM THE CORRESPONDING MANNOSYL TRIMETHYLSILYL ETHER

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Chinese Chemical Letters 1995年第4期6卷 275-278页

作者： He qing HUANG Zhong Jun li Meng Shen CAI School of Pharmaceutical Sciences Beijing Medical UniversityBeijing 100083

In the presence of ***2, 1-O-trimethylsilyi-2,3,4,6-tetra-O-benzyl-α-D-mannopyranose (1)reacted stereoselectively with a series of carboxylic acids to give the corresponding α-mannosyl carboxylates in good yields. T... 详细信息

关键词： t?

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Relationship Between Polymorphism of Cystathionine beta Synthase Gene and Congenital Heart Disease in Chinese Nuclear Families

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Biomedical and Environmental Sciences 2006年第6期19卷 452-456页

作者： XIAO-MING SONG XIAO-YING ZHENG wen-li ZHU LEI HUANG YONG li Department of Nutrition and Food Hygiene School of Public Health Laboratory of Molecular Toxicology and Developmental Molecular Biology Peking University Beijing 100083 China Institute of Population Research Peking University Beijing 100871 China.

Objective To study the relationship between polymorphism of cystathionine beta synthase （CBS） gene and development of congenital heart disease （CHD）. Methods One hundred and twenty-seven CHD case-parent triads were recruited from liaoning Province as patient group, and 129 healthy subjects without family history of birth defect were simultaneously recruited as control group together with their biological parents. For all subjects the polymorphism of CBS gene G919A locus was examined by PCR-ARMS method, Results The frequencies of three genotypes （w/w, w/m, and m/m） in control group were 27.2%, 58,4%, and 14.4%, respectively, with no significant difference in gender. A significant difference in the allele frequency was found between CHD patients and controls, the wild allele frequency was 67,9% in patients and 55.7% in controls CHD parents＇ genotype distribution was significantly different from that in controls. Further comparison of each type of CHD showed that genotype frequencies in several CHD subtypes were significantly different from those in their corresponding controls. The results of TDT analysis showed that no allele transmission disequilibrium existed in CHD nuclear families. Conclusions CBS gene G919A mutation is associated with the development of CHD, and the mutated allele may decrease the risk of CHD.

关键词： Congenital heart disease Gene polymorphism Cystathionine beta synthase Case-control family study

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Analyses on an electronic voltage transformer's failure by its resonance with very fast transient overvoltage and suppression

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High Voltage 2024年第1期9卷 150-162页

作者： Ruoyu Han Houda Zhu qing Chen Hongbin li Yue Tong linshan Han Yang Jiao School of Electrical and Electronic Engineering Huazhong University of Science and TechnologyWuhanChina China Electric Power Research Institute WuhanChina School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhanChina

As voltage measuring devices are widely used in the high voltage power system with a primary-secondary-fusion structure,electronic voltage transformers are directly connected to the primary conductor and would face much more serious electromagnetic environments than general secondary *** a result,they would still experience failures even when general protection measures are adopted to suppress overvoltages'*** address this issue,an innovative method is proposed after analyses are conducted on the resonance between a transformer and an *** this method,an air-cored coil is installed in a transformer to artificially shift its natural frequency and to dodge the high-frequency dominant component of a transient overvoltage,avoiding the aforementioned resonance and suppressing the secondary *** addition,simulations and laboratory tests are conducted to prove this method's validity.

关键词： transient resonance mentioned

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Blockade of c-Src Within the Paraventricular Nucleus Attenuates Inflammatory Cytokines and Oxidative Stress in the Mechanism of the TLR4 Signal Pathway in Salt-Induced Hypertension

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Neuroscience Bulletin 2020年第4期36卷 385-395页

作者： qing Yang Xiao-Jing Yu qing Su Qiu-Yue Yi Xin-Ai Song Xiao-lian Shi Hong-Bao li Jie Qi Guo-qing Zhu Yu-Ming Kang Department of Physiology and Pathophysiology Xi'an Jiaotong University School of Basic Medical SciencesKey Laboratory of Environment and Genes Related to Diseases of the Ministry of EducationXi'an Jiaotong UniversityXi’an 710061China Department of Cardiovascular Surgery First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061China Department of Pharmacology School of Basic Medical SciencesXi’an Jiaotong University Health Science CenterXi’an 710061China Key Laboratory of Cardiovascular Disease and Molecular Intervention Department of PhysiologyNanjing Medical UniversityNanjing 210029China

Toll-like receptor 4 (TLR4) and cellular Src (cSrc) are closely associated with inflammatory cytokines and oxidative stress in hypertension, so we designed this study to explore the exact role of c-Src in the mechanism of action of the TLR4 signaling pathway in salt-induced hypertension. Salt-sensitive rats were given a high salt diet for 10 weeks to induce hypertension. This resulted in higher levels of TLR4, activated c-Src, pro-inflammatory cytokines, oxidative stress, and arterial pressure. Infusion of a TLR4 blocker into the hypothalamic paraventricular nucleus (PVN) decreased the activated c-Src, while microinjection of a c-Src inhibitor attenuated the PVN levels of nuclear factor-kappa B, pro-inflammatory cytokines, and oxidative stress. Our findings suggest that a longterm high-salt diet increases TLR4 expression in the PVN and this promotes the activation of c-Src, which upregulates the expression of pro-inflammatory cytokines and results in the overproduction of reactive oxygen ***, inhibiting central c-Src activity may be a new target for treating hypertension.

关键词： Toll-like receptor 4 Cellular Src Inflammatory cytokines Oxidative stress Hypothalamic paraventricular nucleus Salt-induced hypertension

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