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Copper-Catalyzed Si-H Bond Insertion Polymerization for Synthesis of Optically Active Polyesters Containing Silicon

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Chinese Journal of Chemistry 2022年第1期40卷 21-27页

作者： xiao-Yong Zhai xiao-qing wang Bo Wu Yong-Gui Zhou State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalianLiaoning 116023China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

The synthesis and characterization of chiral polymers with diverse structure remain a long-term challenging research ***,a copper-catalyzed enantioselective insertion of carbene into Si-H bond was applied to polycondensation,giving a new type of optically active degradable polyesters containing Si-C bond in the main *** polymerization features mild condition,broad substrate scope,excellent yields and *** diols could be obtained via reduction of optically active *** analysis indicated these chiral polyesters exhibit good thermal stability.

关键词： Polymerization Insertion Asymmetric catalysis Optically active polyesters Copper

Combustion Characteristics and Kinetics of Anthracite Blending with Pine Sawdust

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Journal of Iron and Steel Research International 2015年第9期22卷 812-817页

作者： Guo-qing LIU qing-cai LIU xiao-qing wang Fei MENG Shan REN Zhen-peng JI College of Materials Science and Engineering Chongqing University

The combustion characteristics and kinetics of anthracite,pine sawdust and their blends were investigated under combustion condition by thermogravimetric analysis,*** fractions of pine sawdust in the blended samples were set to be 30%,50%,and 80%.The results showed that the ignition and burnout temperatures of pine sawdust were lower and the maximum combustion rate was higher than those of *** the increase of pine sawdust content,the ignition temperature and burnout temperature of the blends decreased,while the maximum mass loss rate and the combustible index of the blends increased;that is,the comprehensive combustion property became *** kinetic parameters for the blends combustion under air condition were calculated based on experimental results using Coats-Redfern *** the pine sawdust content varied in the range of 30%-80%,the combustion processes of these blends could be divided into two stages and the combustion reactions belong to the first-order *** values of apparent activation energy at two individual stages decreased from 68.78to47.28kJ·mol-1 and from 113.53 to 46.43kJ·mol-1,respectively.

关键词： pine sawdust anthracite thermogravimetric analysis combustion characteristics apparent activation energy

Partially biobased polymers:The synthesis of polysilylethers via dehydrocoupling catalyzed by an anionic iridium complex

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Chinese Chemical Letters 2020年第5期31卷 1197-1200页

作者： xiao-Yong Zhai xiao-qing wang Yi-Xuan Ding Yong-Gui Zhou State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China

Partially biobased polysilylethers(PSEs)are synthesized via dehydrocoupling polymerization catalyzed by an anionic iridium *** types(AB type or AA and BB type)of monomers are *** acid(LA)and succinic acid(SA)have been ranked within the top 10 chemicals derived from *** type monomers(diols)derived from LA and SA have been applied to the synthesis of *** polymerization reactions employ an air-stable anionic iridium complex bearing a functional bipyridonate ligand as *** to high yields of polymers with number-average molecular weights(Mn)up to 4.38×104 were obtained.A possible catalytic cycle via an Ir-H species is *** on the results of kinetic experiments,apparent activation energy of polymerization in the tempe rature range of 0-10℃is about 38.6 kJ/*** PSEs synthesized from AA and BB type monomers possess good thermal stability(T5=418℃to 437℃)and low glass-transition temperature(Tg=49.6℃).

关键词： Biodegradable polymers Polysilylethers Iridium catalysis Dehydrocoupling polymerization Levulinic acid

Plasma levels of omentin-1 and visfatin in senile patients with coronary heart disease and heart failure

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Asian Pacific Journal of Tropical Medicine 2014年第1期7卷 55-62页

作者： Xiu-Hua wang Ling-Zhi Dou Can Gu xiao-qing wang School of Nursing Central South University Second Hospital of Xiangya Central South University

Objective:To investigate the alteration of plasma levels of omentin-1 and visfatin in elderly patients with coronary heart disease(CHD)and heart ***:Plasma omentin-1 and visfatin levels were measured in 90 subjects(29 stable angina pectoris(SAP)cases,30 unstable angina pectoris(UAP)cases and 31 age-and sex-matched healthy controls(age≥60 years)by enzyme-linked immunosorbent assay *** to the New York Heart Association classification.59 CHDs were divided into three groups:functional I class,11 cases;functional II/III class,36 cases;and functional IV class,12 ***:The plasma level of omentin-1in CHO patients was significantly lower than thai of the control ***-lin SAP group and UAP group were significantly lower compared to the control group(there was no statistical significance between UAP group and SAP group;P>0.05).The plasma level of visfatin in CHD patients was significandy higher than that of the control ***,visfatin in SAP group and UAP group were all significantly higher compared to the control group,while there was no statistical significance between UAP group,and SAP *** plasma omentin-1 level was negatively correlated with SBP(r=-0.264,P<0.05),positively correlated with HDL-c level(r=0.271,P<0.05);the plasma visfatin level was positively correlated with TC(r=0.292,P<0.05),negatively correlated with HDL-c level(r=-0.266,P<0.05).There was a negative correlation between plasma omentin-1 and visfatin levels(r=-0.280,P<0.05).Moreover,multiple linear stepwise regression analysis showed that omentin-1 and visfatin levels might be affected by HDL-c *** regression analysis showed that visfatin could be an independent risk factor of ***:Decreased levels of omentin-1 and increased levels of visfatin may be involved in the occurrence and development of ***-1 and visfatin,independently,may be protective and pro-inflammatory ***,both omentin-1 and visfatin may

关键词： Coronary heart disease Omenlin-1 Visfatin NYHA class Stable angina pectoris Unstable angina pectoris

Relationship between nutrient pollutants and suspended sediments in upper reaches of Yangtze River

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Water Science and Engineering 2015年第2期8卷 121-126页

作者： xiao-qing wang Zhao-cun Liu Ji-lun Miao Ning Zuo Southwest Research Institute of Water Transport Engineering Chongqing Jiaotong University

In order to study the relationship between nutrient pollutants and suspended sediments（SS） in the upper reaches of the Yangtze River and two tributaries, water samples were collected from September 1, 2010 to September 30, 2011 at the Zhutuo, Cuntang, Beibei, Wulong, qingxichang,Wanxian, and Fengjie cross-sections. In the laboratory, the SS concentration and the concentration of SS whose particle size was smaller than0.02 mm were measured. The phosphorus（P）, nitrogen（N）, and permanganate index（CODMn） concentrations in the natural water sample, the settled water sample, and two types of filtered water samples obtained through filter membranes with pore sizes of 0.02 mm and 0.45 mm were monitored synchronously. The results show that there are strong relationships between the P and CODMnconcentrations and the SS concentration. P mainly exists in particulate form, while N mainly exists in dissolved form. SS whose particle size is smaller than 0.02 mm accounts for a high proportion of sediments in the Yangtze River and has a strong effect on water quality. At the seven cross-sections, the amounts of P, N, and CODMnin particulate form in the wet season are higher than in the dry season and the adsorption amounts of P, N, and CODMnper unit mass of sediment are higher in the dry season than in the wet season.

关键词： Suspended sediment Phosphorus Nitrogen Permanganate index

Low remanence temperature coefficient Sm1-xErx(Co,Fe,Cu,Zr)z magnets operating up to 400℃

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Rare Metals 2020年第1期39卷 70-75页

作者： Tian-Li Zhang Bo Zhang Hui wang Cheng-Bao Jiang Zhi-Hong Zhang xiao-qing wang Wei Zhang School of Materials Science and Engineering Beihang UniversityBeijing100191China State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization Baotou Research Institute of Rare EarthsBaotou014030China

Er-doped Sm1-xErx(CobalFe0.15Cu0.08Zr0.03)7.8(x=0,0.1,0.2,0.3)magnets with a low remanence temperature coefficient were prepared by powder metallurgy *** influence of Er content on the remanence and microstructure was investigated.X-ray diffractometer(XRD)analysis showed that the magnets with different Er contents consist of 2:17 R phase and 1:5 H *** electron microscopy(SEM)analysis showed that the composition of the matrix is consistent with stoichiometric composition and no obvious precipitated phase *** the increase in doped Er amount,the temperature stability of Sm1-xErx(CobalFe0.15Cu0.08Zr0.03)7.8(x=0,0.1,0.2,0.3)is getting *** x is up to 0.3,the magnets with a low remanence temperature coefficient are obtained and the remanence descends tardily from 0.86 to 0.80 T as the temperature rises from room temperature to 400℃.These results indicate that Er substitution for Sm in SmCobased permanent magnets together with optimal composition and proper heat treatment could achieve a desired magnetic performance combined with high thermal stability.

关键词： Permanent magnets Low remanence temperature coefficient Er doped Magnetic performance characterization

TBAF-catalyzed cyclization of 6-hydroxyhex-2-ynoates and 7-hydroxyhept-2-ynoates

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Chinese Chemical Letters 2011年第8期22卷 931-934页

作者： xiao qing wang Ping Jing Jia Su Ping Liu Wei Yu State Key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000 China

Tetrabutyl ammonium fluoride（TBAF） was found to be capable of catalyzing the intramolecular hydroalkoxylation of 6- hydroxyhex-2-ynoates and *** reaction could be used to prepare 2,5-substituted THF rings and 2,6- s... 详细信息

关键词： Tetrabutyl ammonium fluoride Et_3SiH Tetrahydrofuran Tetrahydropyran

Estimating Stem Volume Using QuickBird Imagery and Allometric Relationships for Open Populus xiaohei Plantations

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Journal of Integrative Plant Biology 2007年第9期49卷 1304-1312页

作者： xiao-qing wang Zeng-Yuan Li Xing-E Liu Guang Deng Ze-Hui Jiang Research Institute of Wood Industry Chinese Academy of Forestry Beijing 100091 China Research Institute of Forest Resource Information Techniques Chinese Academy of Forestry Beijing 100091 China Intemational Centre for Bamboo and Rattan Beijing 100102 China)

There has been a great deal of interest in studying the crown of trees using remote sensing data. In this study, crown width was extracted from high-resolution QuickBird images for open Populus xiaohei plantations. Regression models for predicting the individual stem volumes of Populus xiaohei were established using extracted crown width, as well as estimated tree parameters （i.e. diameter at breast height [DBH] and tree height） as predictors. Our results indicated that crown width could be accurately extracted from QuickBird images using a multi-scale segmentation approach with a mean relative error of 5.74%, especially for wide-spacing stands. Using either extracted crown width alone or with estimated DBH and tree height can successfully estimate individual stem volume of Populus xiaohei with the R2 value ranging from 0.87 to 0.92 depending on different model forms. In particular, the two second-order polynomial models （model 2 and model 6）, based on QuickBird image-derived crown widths and estimated DBH and tree heights, respectively, were the best at describing the relationship between stem volume and tree characteristics.

关键词： diameter at breast height Populus xiaohei QuickBird image stem volume tree crown tree height.

Novel hydroxymethylbilane synthase gene mutation identified and confirmed in a woman with acute intermittent porphyria:A case report

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World Journal of Clinical Cases 2022年第33期10卷 12319-12327页

作者： Yu-qing Zhou xiao-qing wang Jun Jiang Shu-Ling Huang Zhuo-Jin Dai Qiao-Qiong Kong Department of Endocrinology Dongguan Hospital of Traditional Chinese MedicineDongguan 523003Guangdong ProvinceChina Department of Science and Technology ServicesChina Beijing Macro and Micro Test Biotech Co.Ltd Beijing 100318China The First Clinical Medical College Guangdong Medical UniversityZhanjiang 523003Guangdong ProvinceChina Department of Medicine Wanjiang People's Hospital of DongguanDongguan 523003Guangdong ProvinceChina

BACKGROUND Acute intermittent porphyria(AIP)is a rare autosomal dominant porphyrin metabolic disease caused by a mutation in the hydroxymethylbilane synthase(HMBS)*** study aimed to explore the clinical manifestations of a patient with AIP,to identify a novel HMBS gene mutation in the proband and some of her family members,and to confirm the pathogenicity of the *** SUMMARY A 22-year-old Chinese woman developed severe abdominal pain,lumbago,sinus tachycardia,epileptic seizure,hypertension,and weakness in lower limbs in March,*** examinations indicated hypohepatia and *** last menstrual period was 45 d prior to admission,and she was unaware of the pregnancy,which was confirmed by a pregnancy test after *** exposure of her urine sample for 1 h turned it from yellow to wine *** porphyrin test result was *** on these clinical manifestations,AIP was *** increasing her daily glucose intake(250–300 g/d),abdominal pain was partially *** days after hospitalization,spontaneous vaginal bleeding occurred,which was confirmed as spontaneous abortion;thereafter,her clinical symptoms completely *** testing revealed a novel heterozygous splicing variant of the HMBS gene in exon 10(c.648_651+1delCCAGG)in the proband and four other family *** pathogenicity of the variant was verified through bioinformatic methods and a minigene *** We identified a novel HMBS gene mutation in a Chinese patient with AIP and confirmed its pathogenicity.

关键词： Acute intermittent porphyria Hydroxymethylbilane synthase gene Novel mutation Minigene assay Bioinformatics analysis Case report