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SYNTHESIS OF THE POLYSTYRENE-TYPE ADSORBENTS CONTAINING POLAR GROUPS AND THEIR CAPACITIES IN THE ADSORPTION OF STEVIOSIDE AND GYPENOSIDES

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Science China Chemistry 1992年第2期35卷 129-136页

作者：马建标范云鸽赵芬芝于占如史作清何炳林 Institute of Polymer Chemistry Nankai University Tianjin 300071 PRC

Seven polystyrene-type adsorbents (Ⅰ—Ⅶ) were synthesized by the modification of styrene-divinylbenzene copolymer respectively with hydroxymethyl, aminomethyl, methoxymethyl, phenoxymethyl, (4-hydroxy phenoxy)methyl, (4-acetylphenoxy)methyl, and acetyl groups. Their structures were characterized with chemical methods and physical techniques. The adsorption capacities of the adsorbents to stevioside and gypenosides were determined via batch test in which the HPLC method was used for the analysis of Saponin concentration of solution. The results showed that all the adsorbents could adsorb these saponins to a certain extent, but Ⅵ and Ⅶ had large capacities owing to their moderate polarities.

关键词： styrene-divinylbenzene copolymer polymeric adsorbent stevioside gypenosides.

DYNAMIC RHEOLOGICAL AND THERMAL PROPERTY OF Q-RESIN CONTAINING THERMOTROPIC LIQUID CRYSTALLINE COPOLYESTER AND ITS BLEND WITH PET

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Journal of China Textile University(English Edition) 1994年第1期11卷 59-65页

作者：余木火蒋歧康武秀阁周征龙 China Textile Univ Shanghai China

A thermotropic liquid crystalline copolyester (LCP) based on p-acetoxy-benzoic acid (49.9mol%), 2,7-diacetoxynaphthalene (22.3 mol%), terephthalic acid (22.3%) and Q-resin (polyethylene 2,6-naphthalene, 5.5%) was prepared via melt transesterification, and then a blend was prepared by physically mixing 40% therm0tropic liquid crystallline copolyester and 60% polyethlene terephthalate (PET). The thermal properties of both-4he LCP and the blend were studied by DSC and the result showed that the various transition temperatures for the blend were rather close to those for pure PET. The thermal stability of LCP, blend and PET was characterized by TGA. The dynamic theological properties of LCP and thc blend were studied by the oscillation test on a rheometric mechanical spectrometer( Instron RM3250) with parallel plate disk. The results showed that the theological behavious of the blend melt exhibit as conventional polymeric melt in the whole experimental frequency range (0.02—12 Hz). However, for the melt

关键词： dynamic rheological property liquid crystal copolyester polymeric blend.

Rheological Behavior of the Guanidio Polyelectrolytes

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Journal of Donghua University(English Edition) 2002年第4期19卷 4-6页

作者：张玉梅江建明陈彦模 College of Material Dong Hua UniversityShanghai200051

The rheological behavior of polyhexamethylene guanidine hydrochloride (PHGC) and polyethylene guanidine stearate (PHGS) has been investigated using the capillary rheometer. It is shown that the polyelectrolyte melts are non-Newtonian of shear. thinning fluid. The melt viscosity, the flow activation energy and the flow temperature are high even if the molecular weight is not high. The melting viscosity of PHGC is higher than that of PHGS at the same experimental conditions. By comparison with the case of PHGS the non-Newtonian index of PHGC is smaller, the flow activation energy and the flow temperature of PHGC are higher, which was caused by the difference in their molecular structure.

关键词： Polyelectrolytes, polymeric guanidine, rheological behavior

Isolation and characterization of marine biofilm forming bacteriafrom a ship＇s hull

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Frontiers in Biology 2018年第3期13卷 208-214页

作者： Kavitha S Vimala Raghavan School of Biosciences and Technology Vellore Institute of Technology Vellore-632-014 Tamil Nadu India Centre for Nanotechnology Researchl Vellore Institute of Technologyl Vellore-632 014 Tamil Nadu India

Diverse aquatic microorganisms are capable of colonizing living and non-living surfaces leading to the formation of biofilms. Commonly visualized as a slimy layer, these biofilms are filled with hundreds of other microorganisms compared to free living planktonic cells. Microbial surface colonization and surface-associated metabolic activities also exert several macroscale deleterious effects, including biofouling, biocorrosion and the persistence and transmission of harmful or pathogenic microorganisms and virulence determinants. The present study deals with the isolation and screening of marine bacteria for biofilm formation. The screened isolates were characterized and identified as Pychrobacter celer, Pychrobacter alimentarius and Kocuria rhizophila by 16S rRNA sequencing. Biofilm forming bacteria were isolated by spread plate technique and subjected to screening by microtiter plate assay. The potent biofilm formers were identified by molecular characterization using 16S rRNA gene sequencing. Twelve bacterial isolates were obtained by pour plate technique and subjected to biofilm assay. Among the 12 isolates three isolates which showed maximum biofilm formation were subjected to molecular characterizationby 16S rRNA gene sequencing method. The isolates were identified as Pychrobacter celer, Pychrobacter alimentarius and Kocuria rhizophila. The EPS produced by the three biofilm forming bacteria was extracted and the protein and carbohydrate content determined. Among the isolates screened, isolate 8 (Kocuria rhizophila) produced maximum protein and carbohydrate which was also in accordance with the results of microtiter plate assay.

关键词： biofilm, MTP assay, extracellular polymeric substances, 16S rRNA gene sequencing, Psychrobacter, Kocuria

Wheat gluten protein and its impacts on wheat processing quality

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Frontiers of Agricultural Science and Engineering 2019年第3期6卷 279-287页

作者： Wujun MA Zitong YU Maoyun SHE Yun ZHAO Shahidul ISLAM State Agriculture Biotechnology Centre School of Veterinary and Life Sciences Murdoch University

Before the advent of the wheat genomic era, a wide range of studies were conducted to understand the chemistry and functions of the wheat storage proteins,which are the major determinants of wheat flour the suitability of wheat flour for various end products, such as bread, noodles and cakes.Wheat grain protein is divided into gluten and non-gluten fractions and the wheat processing quality mainly depends on the gluten fractions.Gluten provides the unique extensibility and elasticity of dough that are essential for various wheat end products.Disulfide bonds are formed between cysteine residues,which is the chemical bases for the physical properties of dough.Based on the SDS-extractability, grain protein is divided into SDS-unextractable polymeric protein(UPP)and SDS-extractable polymeric protein.The percentage of UPP is positively related to the formation of disulfide bonds in the dough matrix.In the wheat genomic era, new glutenins with long repetitive central domains that contain a high number of consensus hexapeptide and nonapeptide motifs as well as high content of cysteine and glutamine residues should be targeted.

关键词： wheat gluten consensus motifs disulfide bonds SDS-unextractable polymeric protein glutenins gliadins processing quality storage protein

METAL-CONTAINING ORGANIC MEMBRANE MATERIALS WITH BOTH SEPARATION AND CATALYTIC HYDROGENATION PROPERTIES

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Chinese Science Bulletin 1992年第22期37卷 1934-1935页

作者：高汉荣徐筠廖世健刘韧余道容 Dalian Institute of Chemical Physics Academia Sinica Dalian 116023 PRC Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Academia Sinica Shanghai 200032 PRC

The polymer-supported metal catalysts have been studied extensively in recent years, and it has been reported that the organic polymeric membrane materials modified by functionalizing, doping or coordinating with metal compounds (or complexes ) can be used in gas separation or catalytic reactions. However, up to now, the metal-containing organic polymeric materials with both gas separation capability and catalytic activity have not been reported. Recently, we have prepared a new type of polymeric materials which exhibit both good gas separation property and catalytic hydrogenation activity by the coordination of poly(2, 6-dimethylphenylene oxide) (PPO) with palladium dichloride.

关键词： hydrogenation polymeric palladium doping selectivity complexes Palladium gases slightly alcohol

Citrate-based biomaterial design and their applications

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医用生物力学 2013年第S1期28卷 75-78页

作者： Jian Yang Department of Bioengineering Materials Research InstituteThe Huck Institutes of The Life SciencesThe Pennsylvania State University

1.Introduction Biodegradable polymeric biomaterials have been fabricated into various biomedical implants such as drug delivery nanoparticles,tissue engineering scaffolds and orthopedic devices.Using biodegradable polymers as implant materials is beneficial as the implants are degraded and cleared by the body once their missions are complete,leaving no foreign materials in the body.Driven by the versatile needs in biomedical engineering,searching for ideal functional biodegradable polymers has been an endless effort in the past decades.Among biodegradable polymers,citrate-based biodegradable elastomeric(CABE)polymers have recently received increasing attention because their compliance under force can closely resemble the elastic

关键词： biomaterial biodegradable biomedical implant citrate hydroxyapatite degraded polymeric scaffold compliance

CATALYTIC BEHAVIOR OF PQLYMER-BOUND PALLADIUM COMPLEXES FOR DECARBONYL-ARYLATION

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分子催化 1989年第S1期3卷 22-28页

作者： Guo Zhongcheng and Liu Hanfan (Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China)

The activities and stabilities of the polymer-bound palladium complexes fordecarbonyl-arylation were investigated in this paper.It was found that the activities ofpolymer-bound complexes are comparable to those of their homogeneous counterparts.Among the catalysts examined,the sulfur-containing polymer-bound palladium complexeshave high activity and better stability than the phosphine-,amine-and nitrile-containingpolymerie palladium catalysts.Experimental work was undertaken to evaluate the possibleside reactions.The factors which caused the catalyst deactivation were discussed and the in-flucnce of experimental parameters on the reaction was studied as well.

关键词： palladium complexes nitrile comparable acrylate reused benzoyl catalyzed mercapto polymeric

SOLID STATE VOLTAMMETRY OF ELECTROACTIVE SOLUTES IN POLYMER SOLVENTS(PEO)AT MICROELECTRODE

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Chinese Chemical Letters 1993年第5期4卷 445-448页

作者： Guang Li CHE Shao Jun DONG Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryAcademia SinicaChangchun130022

The present paper describes experiments aimed at delineating significant chemical characteristics of electrochemical reactions in polymeric solutions, including how rigid solvent environments affect mass transport rates, and also discusses the possibility that the microelectrode coated with poly(ethylene oxide)(PEO) film can be used as gas sensor.

关键词： polymeric possibility dissolved coated aimed environments sorption toluene gases SOLID