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Kinetics of ring-opening polymerization of octamethylcyclotetrasiloxane in microemulsion

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Chinese Chemical Letters 2014年第4期25卷 621-626页

作者： Chun-Ning Sun Min-Min Shen Lian-Li Deng Jian-Qiang Mo bao-wen Zhou Laboratory of Cellulose and Lignocellulosics Chemistry Guangzhou Institute of ChemistryChinese Academy of Sciences University of Chinese Academy of Sciences

Polysiloxane latexes were prepared by microemulsion polymerization of octamethylcyclotetrasiloxane （D4） in the absence of co-emulsifier with octadecyl trimethyl ammonium chloride as a cationic emulsifier and potassium hydrate as an initiator. The particle size was determined by the dynamic light scattering （DLS） technique and the reaction rates of the polymerization were discussed. Furthermore, the kinetics was studied by an initial-rate method, and the effects of the monomer, emulsifier and initiator concentrations and the temperature on polymerization conversions were investigated. From the kinetic results, the rate of polymerization, Rp at 80℃ can be expressed as Rp = k[D4]^0.79 [OTAC]^0.64[KOH]^0.38 and the aonarent activation energy（Ea）. which was determined by half-period method, is 95.32 kJ mol^-1.

关键词： Polysiloxane Microemulsion Light scattering (DLS) technique KineticsInitial-rate method

Aqueous Knoevenagel Condensation Catalyzed by Aminopropyl-functionalized MCM-41

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Chinese Chemical Letters 2006年第10期17卷 1293-1296页

作者： Guo Hua GAO Jin bao GAO wen Juan ZHOU Liang LU Ming Yuan HE Shanghai Key Laboratory of Green Chemistry and Chemical Process Department of Chemistry East China Normal University Shanghai 200062

An efficient, environmentally friendly procedure is developed for the condensation of aldchydcs/kctoncs and activated methylene compounds by using an aminopropyl-functionalized MCM-41 catalyst in aqueous solution. Different aldchydcs/kctoncs and activated methylene compounds gave the corresponding alkcncs in 78-97% isolated yields in mild reaction conditions. In comparison with organic solution, the aqueous solution gives higher yields in the same reaction conditions. Further more, the aminopropyl-functionalizcd MCM-41 in aqueous system can be reused for 8 flints without significant decrease of activity.

关键词： Knoevenagel condensation aqueous-phase reaction aminopropyl-functionalized MCM41.

Effect of Reaction Media on Photoreaction of Provitamin D_3

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Chinese Chemical Letters 2001年第4期12卷 309-312页

作者： Yun Yan GAO Yong Yong LIU Bo Jie WANG bao wen ZHANG Yi LI Technical Institute of Physics and Chemistry(The Former Institute of Photographic Chemistry) Chinese Academy of SciencesBeijing 100101

The photoisomerization of provitamin D-3 is carrried out in silica gel-hexane matrix, ethanol and hexane. The results show that in silica gel-hexane matrix and ethanol, the desired product of provitamin D-3 and vitami... 详细信息

关键词： Photoisomerization vitamin D3.

Transcutaneous Electrical Acupoint Stimulation Combined with Warm Acupuncture for Breast Cancer Related Upper Limb Lymphedema:A Retrospective Cohort Study

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Chinese Journal of Integrative Medicine 2023年第6期29卷 534-539页

作者： LU Chao LI Guang-liang DENG De-hou bao wen-long WANG Yan ZHANG Ai-qin Department of Traditional Chinese Medicine the Cancer Hospital of University of Chinese Academy of Sciences(Zhejiang Cancer Hospital)Hangzhou(310022)China Institute of Basic Medicine and Cancer Chinese Academy of SciencesHangzhou(310022)China Department of Breast Medical Oncology the Cancer Hospital of University of Chinese Academy of Sciences(Zhejiang Cancer Hospital)Hangzhou(310022)China

Objective To observe the clinical efficacy of transcutaneous electrical acupoint stimulation(TEAS)combined with warm acupuncture in treating breast cancer associated with upper limb lymphedema(BCRL).Methods This was a retrospective cohort study using a paired control ***-two BCRL patients were assigned to the control group(27 cases)and the treatment group(25 cases).The patients in the control group were treated with lymphedema comprehensive detumescence treatment(CDT)for 4 weeks,including systematic therapy composed of manual lymphatic drainage,compression bandage,skincare,and functional *** patients in the treatment group were treated with TEAS combined with warm acupuncture based on the control group *** treatment lasted for 30 min and was applied twice a week for 4 *** arm circumference(AC)of different positions of the affected limb and the degree of swelling of the affected limb were evaluated before the first treatment and after the last *** clinical efficacy was evaluated according to the degree of edema before and after *** adverse events during treatment were *** The patients’AC and the swelling feeling of the affected limb in the treatment group and the control group were both reduced compared with those before *** with the control group,AC of the wrist joint transverse stria,the midpoint between the wrist joint transverse stria and the elbow joint transverse stria in the treatment group were significantly reduced(P<0.05).The decrease in AC diameter at the midpoint between the elbow joint transverse stria and the axillary transverse stria was the most significant(P<0.01).The swelling degree of the affected limbs in the treatment group was significantly lower than before treatment,and was significantly lower compared with the control group after treatment(P<0.01).The total effective rate was 72%in the treatment group,significantly higher than that in the control group(55.56%,P<0

关键词： transcutaneous electrical acupoint stimulation warm acupuncture breast cancer related upper limb lymphedema comprehensive detumescence treatment clinical efficacy

Preparation of β-Cyclodextrin Modified FusedSilica Capillary and Its Application inCapillary Electrophoresis Enantiom eric Separation

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Chemical Research in Chinese Universities 1999年第3期15卷 232-237页

作者： ZHANG Xin-xiang HONG Feng BAI Jing CHANG wen-bao CI Yun-xiang College of Chemistry Peking UniversityBeijing 100871P.R.China

A simple type of chiral selector immobilized capillaries was prepared and applied to the separation of some enantiomers by capillary electrophoresis(CE) without chiral selective reagents in a buffer solution. β Cyclodextrin (CD) was bonded to the inner wall of fused silica capillary with the aid of 3 (2 cyclooxypropoxyl) propyl trimethoxy silane or 3 aminopropyltriethoxyl silane as bridge. The synthesis conditions such as reaction temperature, reaction ratios, solvents were optimized. The stability and reproducibility of the CD modified capillaries were studied under different operation conditions. It is satisfactory to apply the capillary to the chiral separation of d,l adrenaline and the atracurium besilate diastereoisomers under the optimized conditions.

关键词： U-cyclodextrin-immobilized capillary Capillary electrophoresis Enantiomeric separation

3D Urban Visualization with LOD Techniques

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Journal of China University of Mining and Technology 2006年第1期16卷 64-67页

作者： Wang Yin-xing Li Bai-ying Liu wen-bao Shi Xing-xi College ofGeosciences Shandong University of Science and Technology Taian Shandong 271019 China Nanjing University of Science and Technology Nanjing Jiangsu 210000 China

In 3D urban visualization, large data volumes related to buildings are a major factor that limits the delivery and browsing speed in a web-based computer system. This paper proposes a new approach based on the level of detail （LOD） technique advanced in 3D visualization in computer graphics. The key idea of LOD technique is to generalize details of object surfaces without losing details for delivery and displaying objects. This technique has been successfully used in visualizing one or a few multiple objects in films and other industries. However, applying the technique to 3D urban visualization requires an effective generalization method for urban buildings. Conventional two-dimensional （2D） generalization method at different scales provides a good generalization reference for 3D urban visualization, Yet, it is difficult to determine when and where to retrieve data for displaying buildings. To solve this problem, this paper defines an imaging scale point and image scale region for judging when and where to get the fight data for visualization. The results show that the average response time of view transformations is much decreased.

关键词： digital city level of detail (LOD) generalization visualization image scale point/region

The tissue expression level of BPI gene in piglets from newborn to weaning and its relationship with Gram-negative bacterial infection

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Journal of Integrative Agriculture 2020年第12期19卷 3065-3073页

作者： DAI Chao-hui CAO Yue GAO Zhong-cheng ZHU Guo-qiang WU Sheng-long bao wen-bin Key Laboratory for Animal Genetics BreedingReproduction and Molecular Design of Jiangsu ProvinceCollege of Animal Science and TechnologyYangzhou UniversityYangzhou 225009P.R.China Joint International Research Laboratory of Agriculture and Agri-Product Safety Ministry of Education/Yangzhou UniversityYangzhou 225009P.R.China College of Veterinary Medicine Yangzhou UniversityYangzhou 225009P.R.China

The bactericidal/permeability increasing protein (BPI) has an important function of nonspecific killing of Gram-negative bacteria. In this study, qPCR was used to detect the expression of the BPI gene in twelve tissues of Meishan piglets from birth to weaning. BPI gene overexpression, bacterial adhesions count and indirect immunofluorescence were applied to analyze the relationship between BPI gene expression and the infectivity of Escherichia coli and Salmonella. The results showed that the BPI gene was expressed highly in duodenum, jejunum and ileum (fold changes of relative expression levels were more than 10 000, 500 and 200, respectively). The expression of the BPI gene at 35 days of age was significantly higher (P<0.01) than that at all other days. Transcription of the BPI gene was up-regulated 2 401-fold in porcine intestinal epithelial (IPEC-J2) cells that were transfected with the BPI gene overexpression lentivirus (IPEC-J2-BPI), and significantly higher (P<0.01) than that in negative control cells (IPEC-J2-NC). Protein expression levels in IPEC-J2-BPI cells were also increased. When IPEC-J2 cells were incubated with E. coli and Salmonella, respectively, for 2, 4, 6, 8, 10 and 12 h, the number of bacterial adhesions in IPEC-J2-BPI cells was significantly less (P<0.05) than that in IPEC-J2-NC cells. The results of indirect immunofluorescence analysis showed that the number of bacterial adhesions in IPEC-J2-BPI cells was significantly less (P<0.01) than that in IPEC-J2-NC cells. These results demonstrated that the BPI gene might play an important role in regulating weaning stress especially intestinal-mediated immune response. Overexpression of the BPI gene at the cellular level could significantly enhance the anti-bactericidal ability against Gram-negative bacteria such as E. coli and Salmonella. This has important biological significance in piglet resistance to bacterial diarrhea.

关键词： pig BPI gene Escherichia coli Salmonella disease-resistant breeding

Subsumption Checking between Concept Queries in Different Ontologies Based on Mutual Instances

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Wuhan University Journal of Natural Sciences 2006年第1期11卷 68-72页

作者： KANG Da-zhou LU Jian-jiang XU bao-wen WANG Peng ZHOU Jin Department of Computer Science and Engineering NmtheastUniversity Nanjing 210096 Jiangsu China Jiangsu Institute of Software Quality Nanjing 210096 JiangsuChina Institute of Science The People＇s Liberation Army University of Science and Technology Nanjing 210007 Jiangsu China State Key Laboratory of Software Engineering Wuhan University Wuhan 430072 Hubei China

This paper proposes a checking method based on mutual instances and discusses three key problems in the method： how to deal with mistakes in the mutual instances and how to deal with too many or too few mutual instances. It provides the checking based on the weighted mutual instances considering fault tolerance, gives a way to partition the large-scale mutual instances, and proposes a process greatly reducing the manual annotation work to get more mutual instances. Intension annotation that improves the checking method is also discussed. The method is practical and effective to check subsumption relations between concept queries in different ontologies based on mutual instances.

关键词： ontology concept query subsumption checking mutual instance

UNSTEADY SUPERCAVITATING FLOW PAST CONES

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Journal of Hydrodynamics 2006年第3期18卷 262-272页

作者： HU Chao YANG Hong-lan ZHAO Cun-bao HUANG wen-hu Institute of Aerospace Engineering and Applied mechanics Tongji Universtity Shanghai 200092 China Department of Aerospace Engineering and Mechanics Harbin Institute of Technology Harbin 150001 China Department of Aerospace Engineering and Mechanics Harbin Institute of Technology Harbin 150001 China

Based on integral equation method, the study of unsteady supercavitating flow past cones is presented. The shape and length of supercavity are calculated respectively using the finite difference time discretization method. The characteristics of the shape and length of supercavities, which vary with the cone＇s angle and cavitation number, are investigated respectively, the varied features of some supercavity scales are analyzed when the flow field is perturbed periodically. The curves relationship between cavity length and cavitation number, which are based respectively on present method and other theories, are discussed and compared. It is obviously shown that the supercavity changes have two characteristics： retardance and wave. These results obtained would be useful in the case of design and analysis of cavitator under water.

关键词： supercavitation cavitator unsteady flow,slender body theory integral equation method