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Chinese Journal of Polymer Science 2023年第11期41卷 1714-1724,I0006页

作者： Chang-Tong Song xian-hong Zhang Dong Chen Yu-hong Ma Wan-Tai Yang State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China College of Material Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China

Without any type of su rfactant or dispersing agent,precipitation polymerization has great superiorities in both polymer synthesis and *** the present work,the polymerization of vinyl chloride(VC),n-butyl acrylate(BA),and vinyl acetate(VAc)are conducted in the precipitation polymerization system and series of their random terpolymers poly(vinyl chloride-co-n-butyl acrylate-co-vinyl acetate)(PCBV)are synthesized *** effects of various polymerization conditions,including solvent polarity,temperature,initiator concentration,and monomer feed ratios on the polymerization kinetics,number-average molecular weight(M_(n)),and terpolymer composition are investigated *** solvent and the monomer feed ratio are crucial factors not only for the polymer morphology,but also for the reaction *** the non-polar solvent such as n-hexane,the PCBV displays particle morphology when the composition of BA ratio lower than 10 wt%.Otherwise,the PCBV forms a uniform polymer phase and precipitates out from the *** the polar solvent,e.g.,dimethyl carbonate(DMC)and ethanol,the PCBV polymer maintains a slurry state either in low or in high monomer feed ***,VC based ternary copolymer that obtained in n-hexane has much lower M_(n)(40 wt%)compared with emulsion and suspension ***,the terpolymer can be easily sepa rated by simple centrifugation.

关键词： Precipitation polymerization Copolymerization Vinyl chloride Low molecular weight

Heterotactic Enthalpic Interactions of L-Arginine with 2,2,2-Trifluoroethanol in Aqueous Solutions at 298.15, 303.15 and 310.15 K

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Chemical Research in Chinese Universities 2011年第1期27卷 123-126页

作者： ZHU Yan PANG xian-hong YU Li Department of Chemistry and Chemical Engineering Taishan Medical University Tai ＇an 271016 P. R. China Key Laboratory of Colloid and Interface Chemistry Ministry of Education Shandong University Jinan 250100 P. R China

The enthalpies of mixing of L-arginine with 2,2,2-trifluoroethanol and their respective enthalpies of dilu- tion in aqueous solutions at 298.15, 303.15 and 310.15 K were determined as a function of the mole fraction by flow microcalorimetric measurement. These experimental results were analyzed to obtain heterotactic enthalpic interaction coeffieients（hxy , hxy , hxy） according to the McMillan-Mayer theory. The hxy coefficients between L-arginine molecule studied and 2,2,2-trifluoroethanol molecule in aqueous solutions at 298.15, 303.15 and 310.15 K were found to be all negative. The results were discussed in terms of solute-solute interaction and solute-solvent interaction.

关键词： L-Arginine 2,2,2-Trifluoroetbanol Solute-solute interaction Heterotactic enthalpic interaction

Effects of inhibitors on the protease profiles and degradation of activated Cry toxins in larval midgut juices of Cnaphalocrocis medinalis (Lepidoptera:Pyralidae)

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Journal of Integrative Agriculture 2021年第8期20卷 2195-2203页

作者： YANG Ya-jun XU hong-xing WU Zhi-hong LU Zhong-xian State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products Institute of Plant Protection and MicrobiologyZhejiang Academy of Agricultural SciencesHangzhou 310021P.R.China

Midgut juice plays an important role in food digestion and detoxification in *** order to understand the potential of midgut juice of Cnaphalocrocis medinalis(Guenée)to degrade Bt proteins,the enzymatic activity of midgut juice and its degradation of Bt proteins(Cry2A,Cry1C,Cry1Aa,and Cry1Ac)were evaluated in this study through protease inhibitor *** activities of total protease in midgut juices were significantly inhibited by phenylmethylsulfonyl fluoride(PMSF),tosyl-L-lysine chloromethyl ketone(TLCK),pepstatin A and *** enzymatic activity of chymotrypsin was significantly inhibited by PMSF,and enzymatic activity of trypsin was significantly inhibited by ethylenediaminetetraacetic acid(EDTA),PMSF,tosyl phenylalanine chloromethyl ketone(TPCK),TLCK and trans-epoxysuccinyl-L-leucylamido-(4-guanidino)butane(E-64).EDTA could significantly inhibit the degradation of Cry2A by ***,PMSF,TPCK,and TLCK could inhibit the degradation of Cry1C and ***,PMSF,TPCK,TLCK,and E-64 could inhibit the degradation of *** results indicated that some protease inhibitors hindered various enzymatic activities in the larval midgut of ***,which may reduce the insect’s ability to degrade Bt *** findings may aid the application of protease inhibitors in the management of this insect pest in the future.

关键词： Cnaphalocrocis medinalis midgut juice protease inhibitor enzyme activity degradation Bt protein

Structure and properties of low-dielectric-constant poly(acetoxystyrene-co-octavinyl-polyhedral oligomeric silsesquioxane) hybrid nanocomposite

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Chinese Chemical Letters 2010年第4期21卷 488-491页

作者： Zhang, Chao Xu, hong Yao Zhao, xian Donghua Univ State Key Lab Modificat Chem Fibers & Polymer Mat Shanghai 201620 Peoples R China Donghua Univ Coll Mat Sci & Engn Shanghai 201620 Peoples R China Shandong Univ State Key Lab Crystal Mat Jinan 250100 Peoples R China

Low-dielectric-constant poly(acetoxystyrenezhi-co-octavinyl-polyhedral oligomeric silsesquioxane)(PAS-POSS) organicinorganic hybrid nanocomposite was successfully synthesized via one-step free radical polymerization and characterized by FTIR,high-resolution ~1H NMR,^(29)Si NMR,DSC,TGA,AFM,spectroscopic elhpsometry and dielectric constants measurements. The results show T_g and T_(dec) were elevated dramatically due to the incorporation of inorganic POSS *** ellipsometry and dielectric consta...

关键词： Low-dielectric-constant Hybrid nanocomposite POSS

Additive Preservers of Idempotence and Jordan Homorphisms between Rings of Square Matrices

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Acta Mathematica Sinica,English Series 2009年第4期25卷 639-648页

作者： hong Mei YAO Chong Guang CAO xian ZHANG Department of Mathematics Harbin Institute of Technology Harbin 150001 P. R. China School of Mathematical Science Heilongjiang University Harbin 1500801 P. R. China

Suppose R is an idempotence-diagonalizable ring. Let n and m be two arbitrary positive integers with n ≥ 3. We denote by Mn（R） the ring of all n x n matrices over R. Let （Jn（R）） be the additive subgroup of Mn（R） generated additively by all idempotent matrices. Let JJ = （Jn（R）） or Mn（R）. We describe the additive preservers of idempotence from JJ to Mm（R） when 2 is a unit of R. Thereby, we also characterize the Jordan （respectively, ring and ring anti-） homomorphisms from Mn （R） to Mm （R） when 2 is a unit of R.

关键词： idempotence-diagonalizable ring additive preserver idempotence Jordan homomorphism,ring homomorphism ring anti-homomorphism

pH influences the profiles of midgut extracts in Cnaphalocrocis medinalis(Guenée) and its degradation of activated Cry toxins

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Journal of Integrative Agriculture 2020年第3期19卷 775-784页

Midgut extracts play crucial roles in food digestion and *** evaluated the effect of pH on the profiles of the midgut extracts in rice leaffolder,Cnaphalocrocis medinalis and the degradation of activated Bt-toxins by the midgut extracts under different pH *** protease activity increased slightly with the increase with the simulated pH in the midgut extracts and the maximal protease activity was observed at pH 10.5,while an upward trend was observed as the pH of reaction buffer *** of chymotrypsin-like enzymes increased with pH,both in the buffer and midgut extracts,while the activity of trypsin-like enzyme was *** of the activated Cry2 A by the midgut extracts enhanced as the pH ***2 A was fully degraded into smaller segments at pH *** Cry1 C protein at pH 9.0-10.5 was partially degraded by the midgut *** Cry1 Aa and Cry1 Ac were partially degraded into fragments by the midgut extracts at high *** results will facilitate our further understanding of the interactions between *** and the Cry toxin.

关键词： Cnaphalocrocis medinalis Bacillus thuringiensis pH digestion degradation protease

Molecular Biological and Biochemical Studies Reveal New Pathways Important for Cotton Fiber Development

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Journal of Integrative Plant Biology 2007年第1期49卷 69-74页

作者： Yu Xu hong-Bin Li Yu-xian Zhu National Laboratory of Protein Engineering and Plant Genetic Engineering Peking University Beijing 100871 China

As one of the longest single-celled seed trichomes, fibers provide an excellent model for studying fundamental biological processes such as cell differentiation, cell expansion, and cell wall biosynthesis. In this review, we summarize recent progress in cotton functional genomic studies that characterize the dynamic changes in the transcriptomes of fiber cells. Extensive expression profilings of cotton fiber transcriptomes have provided comprehensive information, as quite a number of transcription factors and enzyme-coding genes have been shown to express preferentially during the fiber elongation period. Biosynthesis of the plant hormone ethylene is found significantly upregulated during the fiber growth period as revealed by both microarray analysis and by biochemical and physiological studies. It is suggested that genetic engineering of the ethylene pathway may improve the quality and the productivity of cotton lint. Many metabolic pathways, such as biosynthesis of cellulose and matrix polysaccharides are preferentially expressed in actively growing fiber cells. Five gene families, including proline-rich proteins （PRP）, arabinogalactan proteins （AGP）, expansins, tubulins and lipid transfer proteins （LTP） are activated during early fiber development, indicating that they may also be needed for cell elongation. In conclusion, we identify a few areas of future research for cotton functional genomic studies.

关键词： cotton fiber functional genomics plant hormone transcriptome transcription factors

Bilioenteric anastomotic stricture in patients with benign and malignant tumors: prevalence,risk factors and treatment

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Hepatobiliary & Pancreatic Diseases International 2017年第4期16卷 412-417页

作者： Ji-Qiao Zhu xian-Liang Li Jian-Tao Kou hong-meng Dong Huan-Ye Liu Chun Bai Jun Ma Qiang He Department of Hepatobiliary and Pancreaticosplenic Surgery Beijing Chaoyang HospitalCapital Medical University

BACKGROUND: Stricture formation at the bilioenteric anastomosis is a rare but important postoperative complication. However, information on this complication is lacking in the literature. In the present study, we aimed to assess its prevalence and predictive factors, and report our experience in managing bilioenteric anastomotic strictures over a ten-year period. METHODS: A total of 420 patients who had undergone bilioenteric anastomosis due to benign or malignant tumors between February 2001 and December 2011 were retrospectively reviewed. Univariate and multivariate modalities were used to identify predictive factors for anastomotic stricture occurrence. Furthermore, the treatment of anastomotic stricture was analyzed. RESULTS: Twenty-one patients (5.0%) were diagnosed with bilioenteric anastomotic stricture. There were 12 males and 9 females with a mean age of 61.6 years. The median time after operation to anastomotic stricture was 13.6 months (range, 1 month to 5 years). Multivariate analysis identified that surgeon volume (6 mm) (odds ratio: 2.871; P=0.0002) had a negative association. Balloon dilation was performed in 18 patients, biliary stenting in 6 patients, and reoperation in 4 patients. Five patients died of tumor recurrence, and one of heart disease. CONCLUSIONS: Bilioenteric anastomotic stricture is an uncommon complication that can be treated primarily by interventional procedures. Bilioenteric anastomosis may be performed by a surgeon in his earlier training period under the guidance of an experienced surgeon. Bile duct size >6 mm may play a protective role.

关键词： anastomotic stricture bilioenteric anastomosis bile duct size surgeon volume

The value of serum metabolomics analysis in predicting the response to cardiac resynchronization therapy

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Journal of Geriatric Cardiology 2019年第7期16卷 529-539,I0001-I0004页

作者： meng-Ruo ZHU Zibire Fulati Yang LIU Wen-Shuo WANG Qian WU Yan-Gang SU Hai-Yan CHEN xian-hong SHU Department of Echocardiography Zhongshan HospitalFudan UniversityShanghai Institute of Cardiovascular DiseasesShanghaiChina Department of Cardiology Zhongshan HospitalFudan UniversityShanghai Institute of Cardiovascular DiseasesShanghaiChina Department of Cardiac Surgery Zhongshan HospitalFudan UniversityShanghai Institute of Cardiovascular DiseasesShanghaiChina Shanghai Center for Bioinformation Technology ShanghaiChina

Objective To construct a prediction model based on metabolic profiling for predicting the response to cardiac resynchronization therapy(CRT).Methods Peripheral venous(PV)and coronary sinus(CS)blood samples were collected from 25 patients with heart failure(HF)at the time of CRT implantation,and PV blood samples were obtained from ten healthy *** serum samples were analyzed by liquid chromatography-mass spectrometry(LC-MS).As per the clinical and echocardiographic assessment at the 6-month follow-up,the HF patients were categorized as CRT responders and *** HF patients had altered serum metabolomic profiles that were significantly different from those of the healthy *** metabolites were also observed between CRT responders and non-responders.A prediction model for CRT response(CRT-Re)was constructed using the concentration levels of the differential metabolites,L-arginine and *** optimal cutoff value of the CRT-Re model was found to be 0.343 by ROC analysis(sensitivity,88.2%;specificity,87.5%;Area under curve(AUC)=0.897,P=0.002).The concentration levels of the differential metabolites,L-arginine and lysyl-gamma-glutamate,in PV serum were significantly correlated with that in CS serum(r=0.945 and 0.680,respectively,all P<0.001).Conclusions Our results suggest that serum-based metabolic profiling may be a potential complementary screening tool for predicting the outcome of CRT.

关键词： Biomarker Cardiac resynchronization therapy Heart failure Metabolomics Serum

Cationic CO_(2)-based Waterborne Polyurethane with High Solid Content and Excellent Ageing Resistance

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Chinese Journal of Polymer Science 2022年第10期40卷 1183-1192,I0008页

作者： hong-Ming Zhang Guang-Ping Han Wan-Li Cheng Shun-Jie Liu xian-hong Wang Key Laboratory of Bio-based Material Science and Technology(Ministry of Education) Northeast Forestry UniversityHarbin 150040China Key Laboratory of Polymer Ecomaterial Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 13022China

High solid content CO_(2)-based cationic waterborne polyurethanes(CWPUs)were prepared using CO_(2)-polyols as soft segment and Nmethyl diethanolamine(MDEA)as hydrophilic *** resulting stable aqueous dispersion displayed a high solid content of 52%with a low MDEA loading of 3.52 wt%.This novel structural CWPU can provide excellent adhesive strength,whose T-peel strength could reach 173.48N/5cm,20%higher than that of ester-based cationic waterborne polyurethane(87.55 N/5cm).The CO_(2)-based CWPU film showed only 2 wt%swelling percentage after 240 min immersion in water,and no change was observed during its immersion in 5 wt%sodium hydroxide *** tensile strength of CO_(2)-WPUs dropped slowly to 91.2%after 480 min immersion in a 5 wt%sodium hydroxide solution,whereas that of esterbased CWPUs dropped quickly to 32%after 240 min and their mechanical properties were lost after 360 min ***,the retention of the tensile strength of the CO_(2)-CWPUs was 81.5%even after 720 min immersion in 10 wt%H_(2)O_(2) solution,while it was only ca.38%for the ester-based *** results indicated that the cationic CO_(2)-based CWPU may be promising waterborne adhesive with outstanding ageing resistance due to its synergistic effect from carbonate and ether groups of CO_(2)-polyol structure.

关键词： Cationic waterborne polyurethane CO_(2)-polyol High solid content Hydrolysis/oxidation resistance