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Aldol Reactions Catalyzed by Proline Functionalized Polyacrylonitrile Fiber

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Chemical Research in Chinese Universities 2013年第2期29卷 256-262页

作者： XIAO Jia li guo-wei zhang Wen-qin Department of Chemistry School of Sciences Tianjin University Tianjin 300072 P. R. China

A proline functionalized fiber catalyst was employed for aldol reactions in water. In the presence of the fiber catalyst, the aldol reactions proceeded smoothly at 40 ℃ and the products were obtained in excellent yields which were higher than those obtained for the reactions catalyzed by L-proline or trans-4-hydroxy-L-proline. This newly developed fiber catalyst is applicable to the reactions of a wide range of aromatic aldehydes and exhibits ex- cellent reusability（up to 6 times） without any additional treatment.

关键词： Polyacrylonitrile fiber(PANF) Proline Aldol reaction Supported catalyst

Process conditions for preparing methanol from cornstalk gas

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Journal of Environmental Sciences 2007年第5期19卷 628-632页

作者： ZHU ling-feng DU Lei li Xin-bao li guo-ting zhang Jie Department of Environmental Engineering North China Institute of Water Conservancy and Hydroelectric Power Zhengzhou 450011 China

The low-heat-value cornstalk gas produced in the down-flow fixed bed gasifier was tentatively used for methanol synthesis. The cornstalk gas was purified and the technical procedures such as deoxygenation, desulfurization, catalytic cracking of tar, purification and hydrogenation were studied. The catalytic experiments of methanol synthesis with cornstalk syngas were carried out in a tubular-flow integral and isothermal reactor. The effect of reaction temperature, pressure, catalysttypes, catalyst particle size, syngas flow at entering end and composition of syngas was investigated. The optimum process conditions and yield of methanol from cornstalk syngas were obtained. The experimental results indicated that the proper catalyst of the synthetic reaction was C301 and the optimum catalyst size （φ） was 0.833 mm×0.351 mm. The optimum operating temperature and pressure were found to be 235℃ and 5 Mpa, respectively. The suitable syngas flow 0.9-1.10 mol/h at entering end was selected and the best composition of syngas were CO 10.49%, CO2 8.8%, N2 37.32%, CnHm 0.95% and H2 40.49%. The best methanol yield is 0.418 g/g cornstalk. The study provided the technical support for the industrial test of methanol production from biomass （cornstalk）gas.

关键词： cornstalk syngas fuel gas purification catalyst methanol synthesis

Selective removal of phenol by spherical particles of α-,β- and γ-cyclodextrin polymers： kinetics and isothermal equilibrium

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Frontiers of Chemical Science and Engineering 2013年第2期7卷 162-169页

作者： Qingchuan CHEN Yicun WEN Yu CANG li li Xuhong guo Rui zhang State Key Laboratory of Chemical Engineering East China University of Science and Technology Shanghai 200237 China

Spherical particles of α-,β- and γ-cyclodextrin （CD） polymers to efficiently remove phenol from waste water were prepared by reverse suspension polymerization with epichlorohydrin as crosslinker in liquid paraffin. By controlling the amounts of crosslinker and water, well- defined spherical polymer particles with controllable size were obtained. Due to the selective inclusion associations between CD groups and phenol, these CD spherical polymer particles were demonstrated to be ideal candidates for removal of phenol. Among them β-CD polymer particles showed the best performance. The kinetics and isothermal equilibrium models were used to fit the experimental data of phenol removal from aqueous solution using these CD polymer particles. It was found that the kinetics followed the Ho and Mckay equation, suggesting that the adsorption process of phenol was controlled by diffusion and the host-guest interaction between CD and phenol. Equilibrium isothermal data can be well fitted by the Freundlich equation. The negative free energy change indicated the spontaneous nature of adsorption of phenol by α-,β- and γ-CD spherical polymer particles, while the lowest free energy for β-CD polymer reflected its best adsorption ability, compared to α- and γ- CD polymer particles.

关键词： cyclodextrin polymer particles phenol,kinetic models adsorption isotherm equilibrium models

Levels and distributions of polychlorinated naphthalenes in sewage sludge of urban wastewater treatment plants

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Chinese Science Bulletin 2008年第4期53卷 508-513页

作者： guo li zhang Bing XIAO Ke zhang QingHua ZHENG MingHui State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences ChineseAcademy of Sciences Beijing 100085 China

Over seventy congeners of polychlorinated naphthalenes(PCNs) in sewage sludge of 8 urban waste-water treatment plants(WWTPs) in Beijing were analyzed by isotope dilution,and high resolution gas chromatography/high resolution mass spectrometry(HRGC/HRMS) *** total PCN concentrations determined in the samples range from 1.48 to 28.21 ng/g dw(dry weight) with TEQ concentrations of 0.11―2.45 pg/g *** levels were lower than those found in other *** and TrCNs were the most dominant homologues of *** similar congener profiles in all the samples suggest the similarity in certain *** from industrial input might be the most significant source of PCNs in the sludges in this study,and thermal processes such as waste incineration and coal combustion may be another source of the PCNs contamination.

关键词：污水污泥萘高分辨质谱法高分辨气相色谱分析城市污水处理厂

Interaction Between Elements Nb and Mo During Precipitation in Microalloyed Austenite

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Journal of Iron and Steel Research International 2010年第9期17卷 60-63页

作者： YUAN Shao-qiang liANG guo li zhang Xiao-juan Department of Eleetromeehanieal Engineering Tangshan College Tangshan 063000 Hebei China

Thermo-simulation test and transmission electron microscopy （TEM） have been used to investigate the interaction between the microalloying elements Nb and Mo within the precipitates during relaxation after austenite deformation of C-Ti-Mo steel and C-Nb-Mo steel. The experimental results demonstrated that the austenitic structure was preserved both in C-Ti-Mo steel and C-Nb-Mo steel even if they were relaxed for 1000 s after deformation at 850℃. The strainqnduced precipitate occurs in two kinds of steel. Through the energy spectrum analysis, it was found that the precipitates were Ti（C, N） and Mo-bearing Nb（C, N） respectively and there exists a strong affinity of Mo for Nb with in the precipitates. Mo atoms would enter the lattice of Nb（C, N） particles probably after Nb（C, N） formation.

关键词： thermo-simulation microstructure strain-induced precipitation relaxation carbonitride

Asymmetric migration dynamics of the tropical Asian and Australasian floras

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Plant Diversity 2023年第1期45卷 20-26页

作者： li-guo zhang Xiao-Qian li Wei-Tao Jin Yu-Juan liu Yao Zhao Jun Rong Xiao-guo Xiang Jiangxi Province Key Laboratory of Watershed Ecosystem Change and Biodiversity Institute of Life Science and School of Life SciencesNanchang UniversityNanchang.Jiangxi330031China State Key Laboratory of Systematic and Evolutionary Botany Chinese Academy of SciencesBeijing.100093China

The tropical Asian and Australasian floras have a close relationship,and is a vital distribution pattern of seed plants *** estimated,more than 81 families and 225 genera of seed plants distributed between tropical Asia and ***,the evolutionary dynamics of two floras were still ***,a total of 29 plant lineages,represented the main clades of seed plants and different habits,were selected to investigate the biotic interchange between tropical Asia and Australasia by integrated dated phylogenies,biogeography,and ancestral state *** statistics indicated that 68 migrations have occurred between tropical Asia and Australasia since the middle Eocene except terminal migrations,and the migration events from tropical Asia to Australasia is more than 2 times of the *** 12 migrations occurred before 15 Ma,whereas the remaining56 migrations occurred after 15 *** number of potential dispersal events(MDE) analysis also shows obvious asymmetry,with southward migration as the main feature,and indicates the climax of bi-directional migrations occurred after 15 *** speculate that the formation of island chains after the Australian-Sundaland collision and climate changes have driven seed plant migrations since the middle ***,biotic dispersal and stable habitat may be crucial for floristic interchange between tropical Asia and Australasia.

关键词： Tropical Asia-Australasia Floristic interchange Biogeography Dispersal Seed plants

Effects of green bonds on bioenergy development under climate change: A case study in Taiwan province, China

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Advances in Climate Change Research 2022年第1期13卷 97-106页

作者： Shan-Shan KUNG Hai-ling li Si-Ru li li-guo zhang Chih-Chun KUNG College of Foreign Studies Hubei University of EconomicsWuhan 430205China Office of Postdoctoral Management Jiangxi University of Finance and EconomicsNanchang 330013China School of International Trade&Economics University of International Business&EconomicsBeijing 100021China School of Economics Jiangxi University of Finance&EconomicsNanchang 330013China

Bioenergy development improves energy security and mitigates climate *** the stable supply of agricultural resources provides a solid basis for efficient bioenergy production,the climate-induced impacts such as changes in lempeniture and precipitation that potentially alter the farming decisions and cropping patterns should be taken into *** study designs two-stage stochastic programming with recourse model to investigate the net bioenergy production and emission reduction,as well as the bioenergy producers'strategies under various market operations and climate *** results show that the net production of biopower and biofuel are relatively stable because the supply of bioenergy feedstocks could remain at a constant level,but the farming decisions,cropping pattern,and resource utilization are likely to be altered by climate-induced *** results also indicate that for efficient bioenergy production,approximately 41.5 billion TWD(9.65 billion CNY)and 33.6 billion TWD(7.81 billion CNY)of bond principal should be invested in crop-based and residual-based technology,*** the face of strict environmental regulations and emission management,biopower technology becomes more competitive,and under such a circumstance,more than 98.3%of the low-cost bond should be invested in biopower development to achieve development efficiency.

关键词： Climate change mitigation Financial mechanism Renewable energy Sustainable development

Overexpression of a Chloroplast-located Peroxiredoxin Q Gene, SsPrxQ, Increases the Salt and Low-temperature Tolerance of Arabidopsis

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Journal of Integrative Plant Biology 2006年第10期48卷 1244-1249页

作者： li-Wen Jing Shi-Hua Chen Xiao-li guo Hui zhang Yan-Xiu Zhao Key Laboratory of Plant Stress Research College of Life Sciences Shandong Normal University Jinan 250014 China

Ablotlc stress, such as salt, drought and extreme temperature, can result in enhanced production of reactive oxygen species （ROS）. Plants have developed both enzymatic ROS-scavenging and non-enzymatic ROS-scavenging systems. The major ROS-scavenging enzymes of plants include superoxide dismutase （SOD）, ascorbate peroxldaae （APX）, catalaae （CAT）, glutathione peroxldaae （GPX） and peroxiredoxina （Prxa）. In the present work, we identified a gene encoding chloroplast-located peroxiredoxin Q, SsPrxQ, from Suaeda salsa L. located at chloroplast. Overexpression of SsPrxQ In Arabidopsis leads to an increase In salt and low-temperature tolerance.

关键词： overexpression peroxiredoxin Q salt and low-temperature tolerance suaeda salsa subcellular localization

Value of ^(18)F-FDG PET-CT in surveillance of postoperative colorectal cancer patients with various carcinoembryonic antigen concentrations

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World Journal of Gastroenterology 2014年第21期20卷 6608-6614页

作者： Yan zhang Bin Feng guo-li zhang Man Hu Zheng Fu Fen Zhao Xiao-li zhang li Kong Jin-Ming Yu Graduate school of Tianjin Medical University Department of Radiation Oncology Shandong Tumor Hospital and Institute (Shandong Academy of Medical Sciences) Affiliated Hospital of Shandong Academy of Medical Sciences Jinan 250031Shandong ProvinceChina Department of Nuclear Medicine Shandong Tumor Hospital and Institute (Shandong Academy of Medical Sciences) Medical College Shandong University School of Medicine and life Sciences University of Jinan

AIM:To evaluate the value of positron emission tomography(PET)/computerized tomography(CT)in surveillance of colorectal cancer(CRC)patients with different carcinoembryonic antigen(CEA)***:One hundred and six postoperative CRC patients who had suspected recurrence or metastasis and received fluorodeoxyglucose(FDG)PET/CT within one week were included in this *** final diagnosis was confirmed by histological examination or clinicalfollow-up over at least six ***:The sensitivity,specificity,and accuracy of FDG PET/CT were 95.2%,82.6%,and 92.5%,and94.8%,81.4%and 92.8%,respectively,in the caseand lesion-based *** sensitivity and accuracy of FDG PET/CT significantly differed from CT in both analyses(χ2=8.186,P=0.004;χ2=6.201,P=0.013;χ2=13.445,P=0.000;χ2=11.194,P=0.001).In the lesion-based analysis,the sensitivity,specificity,and accuracy of FDG PET/CT in the abnormal CEA group were97.8%,82.6%,and 95.6%,compared with 81.3%,80%,and 80.6%for patients with normal CEA *** case-based analysis,the sensitivity,specificity,and accuracy of FDG PET/CT were 97.2%,77.8%,and 95%in abnormal CEA *** in lesion-based analysis,the sensitivity and accuracy of FDG PET/CT in the abnormal CEA group were significantly superior to those in the normal CEA group(χ2=6.432,P=0.011;χ2=7.837,P=0.005).FDG PET/CT changed the management in 45.8%of patients with positive ***:FDG PET/CT showed superior diagnostic value and is an advisable option in surveillance of postoperative CRC patients with a vague diagnosis.

关键词： Colorectal cancer Carcinoembryonic antigen Fluorodeoxyglucose positron emission tomography/computed tomography Recurrence Metastasis