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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 institute of Chemistry{2., guangzhou 510650 china institute of Chemistry{2., Beijing 100080 china Department of Polymer Science, College of Chemical Engineering Dalian University of Technology, Dalian 116012. china 中科院广州化学所 Laboratory of Cellulose and Lignocellulosics Chemistry CAS Guangzhou 510650 Department of Polymer Science College of Chemical Engineering Dalian University of Technology Dalian 116012

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 (2.)-phthalazinone with di(4-chlorophenyl) sulfone, 4,4'-difluoro-benzophenone and phenolphthalin in sulfolane in the presence of K2.O3 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

Leakproof secret sharing protocols with applications to group identification scheme

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Science china(Information sciences) 2012年第5期55卷 1172-1185页

作者： TANG ChunMing 1,2.& GAO ShuHong 3 1 School of Mathematics and Information Science,guangzhou University,guangzhou 510006,{2. 2.State Key Laboratory of Information Security,institute of Software Science,chinese academy of sciences,Beijing 100049,{2. 3 Department of Mathematical sciences,Clemson University,SC 2.634,USA School of Mathematics and Information Science Guangzhou University Guangzhou China State Key Laboratory of Information Security Institute of Software Science Chinese Academy of Sciences Beijing China Department of Mathematical sciences Clemson University Clemson USA

In a traditional (t,n)-threshold secret sharing scheme,t or more honest participants can reconstruct the secret *** the reconstruction process,the individual shares and the secret key K are revealed,hence K is shared once *** this paper,we firstly give the definition of leakproof secret sharing scheme which is composed of a distribution protocol and a proof protocol,then propose two leakproof secret sharing protocols,a computationally secure protocol and an information-theoretically secure *** our protocols,t or more participants can jointly prove that they hold the secret K by using a multi-prover zero-knowledge argument of *** a result,the secret K will be shared for as many times as ***,each participant can detect the dealer in the distribution protocol from cheating,and any verifier can prevent non-qualified set of participants in proof protocol from *** an example of the practical impact of our work we use our techniques to construct group identification schemes with zero-knowledge.

关键词： secret sharing leakproof secret sharing multi-prover zero-knowledge argument proof of knowl-edge group identification scheme

PPARγ phosphorylation mediated by JNK MAPK:a potential role in mac-rophage-derived foam cell formation

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Acta Pharmacologica Sinica 2006年第9期27卷 1146-1152页

作者： Ran YIN~2.Yu-gang DONG~(2.4)Hong-liang LI~3 Z Department of Cardiology,First Affiliated Hospital,Sun Yat-sen University,guangzhou 510080,china 3 {2. of Basic Medical sciences,chinese academy of Medical sciences,Beijing 100005,china Department of Cardiology First Affiliated Hospital Sun Yat-sen University Guangzhou China institute of Basic Medical sciences Chinese Academy of Medical Sciences Beijing China

Aim:To investigate whether oxidized low-density lipoprotein(ox-LDL)modulatesperoxisome proliferator-activated receptorγ(PPARγ)activity through phosphory-lation in macrophages,and the effect of PPARγ phosphorylation on macroph-ages-derived foam cell ***:After exposing the cultured THP-1cells to ox-LDL in the presence or absence of different mitogen-activated proteinkinase(MAPK)inhibitors,PPARγ and phosphorylated PPARγ protein levels weredetected by Western *** activity was analyzed using MAP Kinase As-say *** cholesterol accumulation was assessed by Oil red O stainingand cholesterol oxidase enzymatic *** mRNA level of PPARγtarget genewas determined by reverse transcription-polymerase chain reaction(RT-PCR).Results:ox-LDL evaluated PPARγ phosphorylation status and subsequently de-creased PPARγ target gene expression in a dose-dependent manner,ox-LDL alsoinduced MAPK *** of THP- 1 cells with c-Jun N-terminal kinase-,but not p38- or extracellular signal-regulated kinase-MAPK inhibitor,significantlysuppressed PPARγ phosphorylation induced by ox-LDL,which in turn inhibitedfoam cell ***:In addition to its ligand-dependent activation,ox-LDL modulates PPARγ activity through phosphorylation,which is mediatedby MAPK ***γ phosphorylation mediated by MAPK facilitatesfoam cell formation from macrophages exposed to ox-LDL.

关键词： peroxisome proliferator-activated receptorγ phosphorylation macrophages LDL lipoprotein

Upper-ocean variation in the northern South china Seafrom mooring station observations

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Acta Oceanologica Sinica 2000年第4期19卷 25-35页

作者： Fang Wendong, Shi Ping, Mao Qingwen, Gan Zijun (South china Sea institute of Oceanology,{2., guangzhou 510301, china) South china Sea Inst. of Oceanology Chinese Academy of Sciences Guangzhou 510301 China

CTD temperature, salinity and ADCP current data, which were observed by R/V Shiyan No. 3 during the intensive observational period (IOP) of the South china Sea monsoon experiment (SCSMEX), have been analyzed. Some study results from observations at a mooring station located at the vicinity of continental slope off the south of Dongsha Islands are shown. The dynamic and thermody namic structures as wall as their changes are analyzed to describe the upper-ocean variation in the northern South china Sea during the summer monsoon onset and maintaining periods. The response of near surface water temperature, salinity and current to local sea surface winds is also discussed.

关键词： Northern South china Sea upper-ocean variation summer monsoo$

Kaolin Deposits of Weathering-Residual in the Coastal Area of Guangdong Province

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Acta Geologica Sinica(English Edition) 1991年第3期65卷 289-305,340页

作者： Zhou Guoping Lin Yuchuan institute of Mineral Deposits, chinese {2. of Geological sciences, Beijing,Center of Geological Analysis of Guangdong Province, guangzhou institute of Mineral Deposits Chinese Academy of Geological Sciences Beijing China

Kaolin deposits of weathering-residual type make up a large proportion in different types of kaolin depos-its and are widely used in ceramics, electron ceramics, rubber and paper industries. This paper discusses sys-tematically this type of kaolin deposit with respect to their features of occurrence, mineralogical and chemicalcomposition and transformation of minerals during supergene processes, thus providing some basic data forthe rational exploitation and utilization of the kaolin resources.

关键词： Kaolin Deposits of Weathering-Residual in the Coastal Area of Guangdong Province

On the relationship between convection intensity of South china Sea summer monsoon and air-sea temperature difference in the tropical oceans

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Acta Oceanologica Sinica 2004年第2期23卷 267-278页

作者： LINAilan LIANGJianyin GUDejun WANGDongxiao guangzhouinstituteofTropicalandMarineMeteorologyof{2.MeterologicalAdministration Guangzhou510080China KeyLaboratoryofTropicalMarineEnviromentaldynamics SouthChinaSeaInstituteofOceanologyChineseAcademyofSciencesGuangzhou510301China

The annual, interannual and inter-decadal variability of convection intensity of South china Sea (SCS) summer monsoon and air-sea temperature difference in the tropical ocean is analyzed, and their relationship is discussed using two data sets of 48-a SODA (simple ocean data assimilation) and NCEP/NCAR. Analyses show that in wintertime Indian Ocean (WIO), springtime central tropical Pacific (SCTP) and summertime South china Sea-West Pacific (SSCSWP), air-sea temperature difference is significantly associated with the convection intensity of South china Sea summer monsoon. Correlation of the inter-decadal time scale (above 10 a) is higher and more stable. There is inter-decadal variability of correlation in scales less than 10 a and it is related with the air-sea temperature difference itself for corresponding waters. The inter-decadal variability of the convection intensity during the South china Sea summer monsoon is closely related to the inter-decadal variability of the general circulation of the atmosphere. Since the late period of the 1970s, in the lower troposphere, the cross-equatorial flow from the Southern Hemisphere has intensified. At the upper troposphere layer, the South Asian high and cross-equatorial flow from the Northern Hemisphere has intensified at the same time. Then the monsoon cell has also strengthened and resulted in the reinforcing of the convection of South china Sea summer monsoon.

关键词： tropical oceans air-sea temperature difference South china Sea summer monsoon convection, Convec-tion intensity

EXPERIMENTAL INVESTIGATION ON GAS HYDRATE FORMATION IN PRESENCE OF ADDITIVE COMPONENTS

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化工学报 2003年第Z1期54卷 29-32页

作者： SUN Zhigao~1, FAN Shuanshi~2.and GUO Kaihua~2.(~1 Department of Environment Engineering, Yangzhou University, Yangzhou 2.5009, Jiangsu, china ~2.guangzhou {2. of Energy Conversion, The chinese academy of sciences, guangzhou 510070, Guangdong, china) Department of Environment Engineering Yangzhou University Yangzhou 225009 Jiangsu China guangzhou institute of Energy Conversion The Chinese Academy of Sciences Guangzhou 510070 Guangdong China

Additives were used to increase gas hydrate formation rate and storage capacity. Experimental tests of methane hydrate formation were carried out in surfactant water solutions in a high-pressure *** dodecyl sulfate (SDS) and alkyl polysaccharide glycoside (APG) were used to increase hydrate formation. The effect of SDS on hydrate formation is more pronounced compared APG. Cyclopentane (CP) also improves hydrate formation rates while it cannot increase methane gas storage capacity.

关键词： gas hydrate, additive, storage

Studies on rickettsia-like organism (RLO) disease of tropical marine pearl oyster-Epidemiological investigation of RLO disease in juvenile populations of maricultured Pinctada maxima

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Acta Oceanologica Sinica 2003年第3期22卷 421-435页

作者： Xinzhong Wu , Dengfeng Li, Jinpei Pan, Jingbo Jiang College of Animal sciences,Zhejiang University,Hangzhou 31002.,china. Email: wuxz@zju.edu.cnSouth{2. Sea institute of Oceanology, chinese academy of sciences,guangzhou 510301,chinaSchool of Life sciences,SUN YAT-SEN University,guangzhou 5102.5,china College of Animal sciences Zhejiang University Hangzhou 310029 China South china Sea Inst. of Oceanology Chinese Academy of Sciences Guangzhou 510301 China School of Life sciences SUN YAT-SEN University Guangzhou 510275 China

The death which occurred in juvenile population was a severe problem in the course ofPinctada maxima artificial culture. With the methods of field investigation, histological study and statistic analyses, the epidemiological study was carried out on the disease and death in juvenile populations of Pinctada maxima in the Xinying Pearl Oyster Mariculture Farm of Lingao County (for the A, B and C batches of cultured juveniles hanged in the sea) and the Xincun Pearl Oyster Mariculture Farm of Lingshui County (for the D batch of cultured juvenile hanged in the pond), Hainan Province from November 1993 to April *** results show that the deaths which occurred in juvenile populations of Pinctada maxima presented an outbreak pattern. The peak of mortality rates, in general, occurred in 4-to 6-month old pearl oyster juveniles, and the mortality rates gradully declined with the extention of pearl oyster age after cul-turing 8 months. The correlation between the mortality rates of juvenile populations and mean body lengths of juvenile populations show that the mortality rate become higher under 4 cm of mean body lengths of juvenile population and become obvious declined over 5 cm of mean body lengths. The peak of mortality rate occurred in 1-3 cm of mean body lengths. The results of histological observation showed that rickettsia-like organism inclusions were common, histological widespread infective agent among every batches (A, B, C and D) of cultured juvenile populations. The mean severity indices (SI) of rickettsia-like organism (RLO) infection were positively correlated with mortality rates of juvenile populations. After or within every peaks of RLO infection were all accompanied with the peaks of mortality rates of host populations and the mortality rates declined with decreased RLO infection. So the evidences of histological observation and epidemiology in this study indicated that rickettsia-like organism (RLO) may be as an important pathogenic organism of disease

关键词： Pinctada maxima rickettsia-like organism epidemiology juvenile population

Highly efficient transformation of intact yeast-like conidium cells of Tremella fuciformis by electroporation

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Science china(Life sciences) 2008年第10期51卷 932-940页

作者： GUO LiQiong1,2. LIU Yong1, ZHAO ShuXian1, LIU ErXian1 & LIN JunFang1,2.1 College of Food sciences, South china Agricultural University,{2., china 2.institute of Biomass Research, South china Agricultural University,{2., china College of Food sciences South China Agricultural University Guangzhou China institute of Biomass Research South China Agricultural University Guangzhou China

Tremella fuciformis is one of higher basidiomycetes. Its basidiospore can reproduce yeast-like conidia, also called the blastospore by budding. The yeast-like conidia of T. fuciformis is monokaryotic and easy to culture by submerged fermentation similar to yeast. So it is a good recipient cell for exogenous gene expression. In this study, two expression vectors pGlg-gfp containing gpd-Gl promoter and gfp gene and pGlg-hph containing gpd-Gl promoter and hph gene were constructed. The lowest sensitive concentration of hygromycin for the blastospore was determined on three types of media. Our ex- periments showed that the lowest sensitive concentration of hygromycin for the blastospore was 5 μg/mL on MA medium. The intact blastospores were transformed with the expression vector pGlg-hph by electroporation. The putative transformants were obtained by the MA selective medium. Experi- mental results showed that the most effective parameters for the electroporation of intact blastospores were obtained by using STM buffer, 1.0×108 cells/mL of blastospores, 2.0 μL in transformation volume, 6 μg plasmid, 2.0 kV/cm of electric pulse voltage, stillness culturing on MB liquid medium for 48 h after electroporation. In these transformation conditions, the efficiency reached 2.7 colonies/μg DNA. Co-transformation of plasmid pGlg-gfp and pGlg-hph with ratio of 1:1 was performed by electroporation with the optimal parameters. The putative co-transformants were obtained by the MA selective medium. Eight randomly selected colonies from the vast putative co-transformants were analyzed by PCR de- tection and Southern blotting. The experiments showed that the gfp was integrated into the genomes of three transformants. The co-transformation efficiency was 37.5%. Green fluorescence was observed under laser scanning confocal microscope in these gfp positive transformants. This indicates that the exogenous gfp can be expressed effectively in the yeast-like conidia of T. fuciformis.

关键词： Tremella fuciformis electroporation yeast-like conidia intact cells gene expression hph gene gfp gene