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TRIMETHYLSILYLATED SILICA AS RHEOLOGY MODIFIER FOR SILICONE RESINS

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chinese Journal of Polymer Science 2000年第1期18卷 51-55页

作者： Wei huang ying huang Yunzhao Yu {3. for molecular Science, institute of chemistry, chinese academy of sciences, Beijing 100080, china 中科院化学所北京

Trimethylsilylated silica was synthesized. through hydrolytic condensation of tetraethoxysilane followed by trimethylsilylation. Rheological properties of the silicone resin with trimethylsilylated silica as modifier were studied. It turned out that the particle size of silica was important to the rheological behavior of the modified resin. Trimethylsilylated silica of medium particle size shows the strongest tendency of forming physical network in the resin.

关键词： silica trimethylsilylation rheology modifier silicone resins

SOLID PHASE TRANSITION OF SYNDIOTACTIC POLYSTYRENE IN SUPERCRITICAL CO_2

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chinese Journal of Polymer Science 2002年第3期20卷 191-196页

作者： Yu-ying Li Jia-song He State Key Laboratory of Engineering Plastics, center for molecular Science,{3. chinese academy of sciences, Beijing 100080 china chinese Acad Sci Inst Chem Ctr Mol Sci State Key Lab Engn Plast Beijing 100080 Peoples R China

Solid phase transition of the a form crystals to the 3.form crystals in syndiotactic polystyrene (sPS) samples has occurred in supercritical CO2. This transformation is different from those detected under other conditions. The effects of some factors (e.g. time, temperature, and pressure) on the solid phase transformation of sPS in supercritical CO2 were analyzed in detail. Experimental results show that longer time, higher temperature or higher pressure favors the transformation of the a form crystals to the beta form crystals.

关键词： solid phase transition syndiotactic polystyrene supercritical CO2

Combined toxicity of copper and cadmium to six rice genotypes (Oryza sativa L.)

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Journal of Environmental sciences 2009年第5期21卷 647-653页

作者： huang Yizong, HU ying, LIU Yunxia Research center for Eco-Environmental {3., chinese academy of sciences, Beijing 100085, china. Research center for Eco-Environmental sciences Chinese Academy of Sciences Beijing 100085 China

Accumulations of copper （Cu） and cadmium （Cd） in six rice cultivars （94D-22, 94D-54, 94D-64, Gui63., YY-1, and KY13.0） were evaluated through exposure to heavy metal contamination （100 mg/kg Cu, 1.0 mg/kg Cd, and 100 mg/kg Cu ＋ 1.0 mg/kg Cd） in a greenhouse. The dry weights of shoot and root, concentrations of Cu and Cd in plant tissues and the Cu, Cd, P, Fe concentrations in the root surface iron plaques were analyzed eight weeks later after treatment. The results indicated that the plant biomass was mainly determined by rice genotypes, not Cu and Cd content in soil. Separated treatment with Cu/Cd increased each metal level in shoot, root and iron plaques. Soil Cu enhanced Cd accumulation in tissues. In contrast, Cu concentrations in shoot and root was unaffected by soil Cd. Compared to single metal contamination, combined treatment increased Cd content by 110.6%, 77.0%, and 45.2% in shoot, and by 112.7%, 51.2% and 18.4% in root for Gui63., YY-1, and KY13.0, respectively. The content level of Cu or Cd in root surface iron plaques was not affected by their soil content. Cu promoted Fe accumulation in iron plaques, while Cd has no effect on P and Fe accumulation in it. The translocation of Cu and Cd from iron plaques to root and shoot was also discussed. These results might be beneficial in selecting cultivars with low heavy metal accumulation and designing strategies for soil bioremediation.

关键词： Cu Cd combined contamination soil uptake accumulation root surface iron plaques

A Calorimeter for Measuring the Enthalpy of Solution of Solid Solutes in Supercritical Fluids and Study on CO2-Naphthlene System

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chinese Chemical Letters 2001年第1期12卷 79-80页

作者： Xiao Gang ZHANG, Guang ying YANG , Bu Xing HAN*, Xi Feng ZHANG, Hai Ke YAN center for molecular {3., institute of chemistry, the chinese academy of sciences, Beijing 100080 center for molecular sciences Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

An apparatus for measuring the enthalpy of solution of solids in supercritical fluids (SCFs) was constructed. The enthalpy of solution (ΔH) of naphthalene in supercritical (SC) CO2 was measured at 3.8.15 K in the pressure range from 8~11 MPa. It was found that ΔH was negative in the pressure range from 8 to 10 MPa, and the absolute value of ΔH decreases with increasing pressure. However, ΔH became positive at the pressures higher than 10 MPa. This unusual phenomenon can be explained by clustering between CO2 and naphthalene.

关键词： Solution enthalpy supercritical fluid molecular interaction

IN SITU INTERFEROMETRIC STUDY ON THE GELATION PROCESS OF POLYACRYLIC ACID GELS

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chinese Journal of Polymer Science 2000年第4期18卷 373-377页

作者： ying Guan Qiang Chen Xian-min Zhang Yu-xing Peng Jian Xu Polymer Physics Laboratory, center for molecular Science,{3., chinese academy of sciences, Beijing 100080, china Department of Information & Electronic Engineering, Zhejiang University, Hangzhou 3.0027, china Chengdu institute of Organic chemistry, chinese academy of sciences, Chengdu 610041, china 中科院化学所高分子物理及化学国家重点实验室北京浙江大学浙江杭州中科院成都有机化学所四川成都

In situ interferometry was used to investigate the gelation process of polyacrylic acid (PAA) gels. The basic principle of the in situ interferometry technique is illustrated. It can give sufficient information for non-destructive and successful investigation of the whole gelation process. The effect of initiator concentration on the gelation process was studied. The polymerization rate of AA increases with increasing initiator concentration. The error arising from the thermal effect in the gelation process can be neglected.

关键词： in situ interferometry gelation polyacrylic acid

SYNTHESIS AND CHARACTERIZATION OF PHTHALAZINONE POLY(ARYL ETHER SULFONE KETONE)WITH CARBONYL GROUP

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chinese Journal of Polymer Science 2002年第3期20卷 225-229页

作者： ying-nan Xuan Yan Gao Yong huang Xi-gao Jian Laboratory of Cellulose and Lignocellulosics chemistry Guangzhou{3. chinese academy of sciences, Guangzhou 510650 china{3. chinese academy of sciences, Beijing 100080 china Department of Polymer Science, College of Chemical Engineering Dalian University of Technology, Dalian 116012, china chinese Acad Sci Guangzhou Inst Chem Lab Cellulose & Lignocellulos Chem Guangzhou 510650 Peoples R China

A kind of novel heat-resistant, high performance engineering thermoplastic phthalazinone poly(aryl ether sulfone ketone) (PPESK) containing a carboxyl group in its side chain was prepared by the nucleophilic displacement reaction of 4-(4-hydroxylphenyl)- 1 (2H)-phthalazinone with di(4-chlorophenyl) sulfone, 4,4'-difluoro-benzophenone and phenolphthalin in sulfolane in the presence of K2CO3.to produce high molecular weight polymers which can be dissolved in some polar solvents such as chloroform and nitrobenzene at room temperature and can be easily cast into flexible, yellowish and transparent films. PPESK is an amorphous polymer having a decomposition temperature above 400degreesC, which indicates that it has high thermal stability. At the same time, the thermal properties of PPESKs with dicyandiamide (DICY) as curing agent indicated that the heat-resistance properties of the PPESKs are improved after curing. The apparent activation energy (A-E) of the cross-linking reaction and the reaction order (n) of PPESK/DICY were found to be 52.2 kJ/mol and ca. 1.0, respectively. Therefore, the cross-linking reaction is approximately a first order reaction.

关键词： poly(aryl ether sulfone ketone) synthesis active pendant group

MECHANISM-TRANSFORMATION SYNTHESIS AND CHARACTERIZATION OF POLY(STYRENE-b-2-ETHYL-2-OXAZOLINE) DIBLOCK COPOLYMER

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chinese Journal of Polymer Science 1999年第2期17卷 145-150页

作者： Sheng-qing Xu Han-ying Zhao Tao Tang Bao-tong huang Changchun institute of Applied {3., chinese academy of sciences, Changchun 13.022, china 中科院长春应用化学所吉林长春

By mechanism-transformation (anionic --> cationic) poly(styrene-6-2-ethyl-2-oxazoline) diblock copolymer, PS-b-PEOx, was synthesized in two steps. The first step is the polymerization of styrene block capped with ethylene oxide and its tosylation; the second step is the cationic ring-opening polymerization of 2-ethyl-2-oxazoline. The products were thoroughly characterized by various methods, such as H-1-NMR, IR, DMA, TEM and SAXS. The results show that the copolymer obtained possesses high molecular weight and narrow molecular weight distribution.

关键词： diblock copolymer mechanism-transformation polymerization 2-ethyl-2-oxazoline styrene characterization

Drug repurposing for cancer therapy

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Signal Transduction and Targeted Therapy 2024年第5期9卷 1981-2013页

作者： ying Xia Ming Sun Hai huang Wei-Lin Jin center for Clinical Laboratories The Affiliated Hospital of Guizhou Medical UniversityGuiyang 550004PR China The First Affiliated Hospital of Guizhou University of Traditional chinese Medicine Guiyang 550001PR China School of Clinical Laboratory Science Guizhou Medical UniversityGuiyang 550004PR China Division of Gastroenterology and Hepatology Department of Medicine andDepartment of OncologySidney Kimmel Comprehensive Cancer CenterJohns Hopkins University School of MedicineBaltimoreMD 21287USA institute of Cancer Neuroscience Medical Frontier Innovation Research CenterThe First Hospital of Lanzhou UniversityThe First Clinical Medical College of Lanzhou UniversityLanzhou 730000PR China

Cancer,a complex and multifactorial disease,presents a significant challenge to global *** significant advances in surgical,radiotherapeutic and immunological approaches,which have improved cancer treatment outcomes,drug therapy continues to serve as a key therapeutic ***,the clinical efficacy of drug therapy is often constrained by drug resistance and severe toxic side effects,and thus there remains a critical need to develop novel cancer *** promising strategy that has received widespread attention in recent years is drug repurposing:the identification of new applications for existing,clinically approved *** repurposing possesses several inherent advantages in the context of cancer treatment since repurposed drugs are typically cost-effective,proven to be safe,and can significantly expedite the drug development process due to their already established safety *** light of this,the present review offers a comprehensive overview of the various methods employed in drug repurposing,specifically focusing on the repurposing of drugs to treat *** describe the antitumor properties of candidate drugs,and discuss in detail how they target both the hallmarks of cancer in tumor cells and the surrounding tumor *** addition,we examine the innovative strategy of integrating drug repurposing with nanotechnology to enhance topical drug *** also emphasize the critical role that repurposed drugs can play when used as part of a combination therapy *** conclude,we outline the challenges associated with repurposing drugs and consider the future prospects of these repurposed drugs transitioning into clinical application.

关键词： drugs integrating spite

Effects of maize root exudates and organic acids on the desorption of phenanthrene from soils

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Journal of Environmental sciences 2009年第7期21卷 920-926页

作者： ZHU Yanhong, ZHANG Shuzhen, huang Honglin, WEN Bei State Key Laboratory of Environmental chemistry and Ecotoxicology, Research center for Eco-Environmental {3., chinese academy of sciences, Beijing 100085, china. State Key Laboratory of Environmental chemistry and Ecotoxicology

The effects of maize root exudates and low-molecular-weight-organic anions （LMWOAs） on the desorption of phenanthrene from eight artificially contaminated soils were evaluated. A significant negative correlation was observed between the amounts of phenanthrene desorbed and the soil organic carbon （SOC） contents （P 〈 0.01）, and the influences of soil pH and clay content on phenanthrene desorption were insignificant （P 〉 0.1）. Neither maize root exudates nor oxalate and citrate anions influenced desorption of phenanthrene with the addition of NaN3. A faster phenanthrene desorption occurred without the addition of NaN3.in the presence of maize root exudates than oxalate or citrate due to the enhanced degradation by root exudates. Without the addition of NAN3. oxalate or citrate at different concentrations could inhibit phenanthrene desorption to different extents and the inhibiting effect by citrate was more significant than by oxalate. This study leads to the conclusion that maize root exudates can not enhance the desorption under abiotic condition with the addition of NaN3.and can promote the desorption of phenanthrene in soils without the addition of NaN3.

关键词： phenanthrene desorption low-molecular-weight-organic anions (LMWOAs) root exudates soils