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Frontiers of Environmental Science & Engineering 2007年第2期1卷 147-152页

作者： LU Sihua LIU Ying shao Min HUANG shan State Joint Key Laboratory of Environmental Simulation and Pollution Control Peking UniversityBeijing 100871China

Volatile organic compounds(VOCs)were measured at six sites in Beijing in August,*** to 148 VOC species,including C_(3) to C_(12) alkanes,C_(3) to C_(11) alkenes,C_(6) to C_(12) aromatics,and halogenated hydrocarbons,were *** the concentrations differed at the sites,the chemical compositions were similar,except for the Tongzhou site where aromatics were significantly high in the *** on the source profiles measured from previous studies,the source apportionment of ambient VOCs was preformed by deploying the chemical mass balance(CMB)*** results show that urban VOCs are predominant from mobile source emissions,which contribute more than 50% of the VOCs(in mass concentrations)to ambient air at most *** important sources are gasoline evaporation,painting,and *** exception is at the Tongzhou site where vehicle exhaust,painting,and solvents have about equal contribution,around 35% of the ambient VOC *** the receptor model is not valid for deriving the sources of reactive species,such as isoprene and 1,3-butadiene,other methodologies need to be further explored.

关键词： volatile organic compounds(VOCs) chemical composition chemical mass balance model reactive species

Use of polarization freedom beyond polarizationdivision multiplexing to support high-speed and spectral-efficient data transmission

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Light(Science & Applications) 2016年第1期5卷 259-265页

作者： Zhi-Yu Chen Lian-shan Yan Yan pan Lin Jiang An-Lin Yi Wei pan Bin Luo Center for Information Photonics and Communications School of Information Science and TechnologySouthwest Jiaotong UniversityChengdu 610031China

Increasing the system capacity and spectral efficiency(SE)per unit bandwidth is one of the ultimate goals for data network designers,especially when using technologies compatible with current embedded fiber *** these,the polarizationdivision-multiplexing(PDM)scheme,which supports two independent data channels on a single wavelength with orthogonal polarization states,has become a standard one in most state-of-art telecommunication ***,however,only two polarization states(that is,PDM)can be used,setting a barrier for further SE *** by coherent detection and digital signal processing,we propose and experimentally demonstrate a scheme for pseudo-PDM of four states(PPDM-4)by manipulation of four linearly polarized data channels with the same *** any modification of the fiber link,we successfully transmit a 100-Gb s−1 PPDM-4 differential-phase-shift-keying signal over a 150-km single-mode fiber *** a method is expected to open new possibilities to fully explore the use of polarization freedom for capacity and SE improvement over existing fiber systems.

关键词： coherent detection optical communication pseudo-polarization-division multiplexing spectral efficiency

Embodied exergy-based assessment of energy and resource consumption of buildings

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Frontiers of Earth Science 2014年第1期8卷 150-162页

作者： Jing MENG Zhi LI Jiashuo LI Ling shao Mengyao HAN shan GUO College of Urban and Environmental Sciences Peking University Beijing 100871 China State Key Laboratory for Turbulence and Complex Systems College of Engineering Peking University Beijing 100871 China

As an effective approach to achieve a more unified and scientific assessment, embodied exergy-based analysis is devised to assess the energy and resource consumption of buildings. A systematic accounting of the landmark buildings in E-town, Beijing is performed, on the basis of raw project data in the Bill of Quantities （BOQ） and the most recent embodied exergy intensities for the Chinese economy in 2007 with 135 industrial sectors. The embodied exergy of the engineering structure of the case buildings is quantified as 4.95E ＋ 14 J, corresponding to an intensity of 8.25E ＋ 09 J/m2 floor area. Total exergy of 51.9% and 28.8% are embodied in the steel and concrete inputs, respectively, due to the fact that the case buildings are structured of reinforced-concrete. The fossil fuel source （coal, crude oil, and natural gas） is predominant among four categories of natural resources （fossil fuel, biological, mineral, and environmental）, accounting for 89.9% of the embodied exergy, with coal as the dominant energy resource （75.5%）. The material accounts for 89.5% of the embodied exergy, in contrast to 9.0%, 1.4%, and 0.1% for manpower, energy, and equipment respectively. This result indicates that great attention should be given to the use of various materials vs. their value of their contribution

关键词： energy resources exergy analysis greenbuilding ecological assessment

Geomatics for smart cities-concept,key techniques,and applications

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Geo-Spatial Information Science 2013年第1期16卷 13-24页

作者： LI Deren shan Jie shao Zhenfeng ZHOU Xiran YAO Yuan State Key Laboratory of Information Engineering in Surveying Mappingand Remote SensingWuhan UniversityWuhan 430079China School of Remote Sensing and Information Engineering Wuhan UniversityWuhan 430079China School of Civil Engineering Purdue UniversityWest Lafayette IN 47907USA

The progressive transition from digital to smart cities has become a reality in recent *** on the fundamental concept of smart cities,along with their supporting techniques,have attracted unprecedented *** study first discusses the concept of smart cities,where it is pointed out that the real city and the digital city can be integrated into a smart city by using ubiquitous sensor networks(USN)or the Internet of *** intelligent services for city management and public services can be provided in smart cities through massive and complex calculation,analysis,and data mining on cloud computing platforms.A smart city’s representative characteristics are summarized here to demonstrate that smart cities are superior for offering technical securities and intelligent *** municipal supervision,smart transportation,smart environment monitoring,and smart tourism are used as examples to support the discussion.

关键词： smart city digital city Internet of Things ubiquitous sensor network cloud computing intelligent service

Prediction of the Atomic Electron Affinities Using a Wavelet Neural Network

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Chinese Chemical Letters 1998年第2期9卷 203-206页

作者： Liu, L shao, XG Cai, WS Jiang, Y pan, ZX Univ Sci & Technol China Dept Chem Hefei 230026 Peoples R China Univ Sci & Technol China Dept Appl Chem Hefei 230026 Peoples R China Univ Sci & Technol China Dept Phys Hefei 230026 Peoples R China

Wavelet Neural Network (WNN) was employed in a rapid calculation of the atomic electron affinities, with atomic ionization potentials and atomic electron configurations chosen as input parameters. Many unmeasured valu... 详细信息

关键词： Wavelet Neural Network (WNN) atomic electron affinities

Synthesis of N-alkyl substituted iminosugars from D-ribose

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Chinese Chemical Letters 2018年第1期29卷 73-75页

作者： Haibo Wang Yang pan Qin Tang Wei Zou Huawu shao Natural Products Research Center Chengdu Institute of Biology Chinese Academy of Sciences Chengdu 610041 China Institute for Biological Sciences National Research Council of Canada Ottawa KIA OR6 Canada zhejiang Hongyuan Pharmaceutical Co. Ltd. Linhai 317000 China Graduate School of Chinese Academy of Sciences Belting 100049 China

An effective and facile method for the synthesis of N-alkylated hydroxylpyrrolidine and hydroxylpiper- idine is described, A number of N-alkyl substituted iminosugars were prepared using iodine-induced intramolecular ... 详细信息

关键词： lminosugar Pyrrolidine Piperidine Glycosidase D-Ribose

Structure and Fluorescence Property of a Two-fold Interpenetrated Three-dimensional Zn（Ⅱ）Complex Constructed by Terephthalate and 1,3-Dipyridyl Benzene

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Chemical Research in Chinese Universities 2015年第3期31卷 328-331页

作者： XU Jingyao ZHANG Lei shao Xueman pan Chengling XU Jiqing Laboratory of Multiscale Materials and Molecular Catalysis School of Materials Science and EngineeringAnhui University of Science and Technology Huainan 232001 P.R.China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin University Changchun 130012 P.R.China

A new coordination polymer { [Zn2（dpb）z（bdc）2]· 1.3H20}n（1） was prepared under solvothermal condition using terephthalate（1,4-Hzbdc） as well as 1,3-dipyridyl benzene（l,3-dpb） as initiators. The complex was characterized by means of infrared spectroscopy（IR）, thermogravimetric analysis（TGA）, powder X-ray diffraction（XRD） and X-ray single-crystal diffraction. The results indicate that complex 1 crystallizes in the monoclinic system with space group of P21/c. *** Zn（Ⅱ） ions are linked by ligand dpbto form infiniteLy meso-helical or zigzag chains, which are further connected to form a two-fold interpenetrated 3D framework, in which there exists strong hydrogen bonds（O--H...O） between the interpenetrated frameworks. In addition, the solid-state fluorescence behavior of complex 1 was also discussed.

关键词： Coordination polymer V-Shaped ligand Solid-state fluorescence Zinc

ELECTROCHEMICAL SYNTHESIS AND PROPERTIES OF POLY(AZURE B)

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Chinese Journal of Polymer Science 2001年第4期19卷 359-370页

作者： Dan shan shao-lin Mu Department of Chemistry School of Sciences, Yangzhou University Yangzhou 225002, China Yangzhou Univ Sch Sci Dept Chem Yangzhou 225002 Peoples R China

A blue poly(azure B) film has been synthesized using repeated potential cycling between -0.25 and 1.10 V (versus SCE). The electrolytic solution consisted of 2.5 mmol dm(-3) azure B, 0.5 mol dm(-3) NaCl and 0.2 mol dm(-3) NaH2PO4 at the pH range of 2.0 to 11.0. The in situ visible spectrum during electrolysis of azure B shows that the intensity at 740 nm peak increases with increasing numbers of potential cycles, which is attributable to the formation of poly(azure B). The wavelength of its corresponding absorption peak is 98 nm longer than that of azure B. The polymerization rate is strongly affected by pH values. The anodic peak potential and cathodic peak potential of the poly(azure B) in a solution of pH 3.0 are not affected by increasing the scan rate from 25 to 600 mV s(-1). Poly(azure B) has good electrochemical reversibility and fast charge transfer characteristic in the pH range of 2.0 and 11.0. The conductivity of poly(azure B) is 1.5 x 10(-4) S cm(-1) According to the differences between FTIR spectra of poly(azure B) and azure B, an electrochemical polymerization mechanism of azure B is proposed in this paper.

关键词： azure B electrochemical polymerization electrochemical properties conductivity in situ UV-visible spectra FTIR spectra

Parthenolide inhibits proliferation of vascular smooth muscle cells through induction of G_0/G_1 phase cell cycle arrest

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第7期10卷 528-535页

作者： shao-xiang WENG Mei-hua SUI shan CHEN Jian-an WANG Geng XU Ji MA Jiang shan Lu FANG Department of Cardiology the Second Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310009 China Department of Chemical and Biochemical Engineering Zhejiang University Hangzhou 310027 China Department of Pathology and Laboratory Medicine Medical University of South Carolina Charleston SC 29425 USA

Objective： This study is to determine the effect of the natural product parthenolide, a sesquiterpene lactone isolated from extracts of the herb Tanacetum parthenium, on the proliferation of vascular smooth muscle cells （VSMCs）. Methods： Rat aortic VSMCs were isolated and cultured in vitro, and treated with different concentrations ofparthenolide （l 0, 20 and 30 μmol/L）. [^3H]thymidine incorporation was used as an index of cell proliferation. Cell cycle progression and distribution were determined by flow cytometric analysis. Furthermore, the expression of several regulatory proteins relevant to VSMC proliferation including IκBα, cyclooxygenase-2 （Cox-2）, p21, and p27 was examined to investigate the potential molecular mechanism. Results： Treatment with parthenolide significantly decreased the [^3H]thymidine incorporation into DNA by 30%-56% relative to control values in a dose-dependent manner （P〈0.05）. Addition of parthenolide also increased cell population at G0/G1 phase by 19.2%-65.7% （P〈0.05） and decreased cell population at S phase by 50.7%-84.8% （P〈0.05）, which is consistent with its stimulatory effects on p21 and p27. In addition, parthenolide also increased IκBα expression and reduced Cox-2 expression in a time-dependent manner. Conclusion： Our results show that parthenolide significantly inhibits the VSMC proliferation by inducing G0/G1 cell cycle arrest. IκBα and Cox-2 are likely involved in such inhibitory effect ofparthenolide on VSMC proliferation. These findings warrant further investigation on potential therapeutic implications ofparthenolide on VSMC proliferation in vivo.

关键词： Parthenolide Vascular smooth muscle cell (VSMC) Cell proliferation IκBα Cyclooxygenase-2 (Cox-2) p21

Nanodiamonds decorated yolk-shell ZnFe_(2)O_(4) sphere as magnetically separable and recyclable composite for boosting antibiotic degradation performance

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Chinese Journal of Chemical Engineering 2023年第2期54卷 162-172页

作者： Jingjing pan Haoran Sun Keyi Chen Yuhao Zhang Pengnian shan Weilong Shi Feng Guo School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212003China School of Material Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China College of Chemistry Zhengzhou UniversityZhengzhou 450001China

Photocatalysis is an environmentally friendly and energy-saving technology, which can effectively remove persistent dangerous pollutants in the water. Pitifully, optical absorption capacity and carrier separation have become major bottlenecks for marvelous photocatalytic performance of ***, to address these issue, Nanodiamonds/yolk-shell ZnFe_(2)O_(4) spheres(NDs/ZFO) nanocomposites were successfully constructed via a facile two-step of solvothermal and calcination methods. The synthesized optimal NDs/ZFO-10 nanocomposite exhibits superior photocatalytic degradation activity of antibiotic under visible light, approximately 85% of the total tetracycline(TC) is degraded, and this photocatalyst shows durable cycling stability. This stems from two aspects of refinement: improvement of light absorption capacity and photo-induced charges migration and separation. In addition, the NDs/ZFO composite photocatalyst features excellent magnetic recovery capability, facilitating the recovery of photocatalyst in industry. This study opens a new chapter in the combination of NDs with magnetic materials, and deepens the understanding of the application of NDs modified composite photocatalysts.

关键词： Nanodiamonds ZnFe_(2)O_(4) Photocatalytic Heterojunction Antibiotic degradation