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Synthesis of 1,1,3,3,5,5-hexamethyl-1,5-bis[(3-ethyl-3-methoxyoxetane)propyl]trisiloxane and Research on Its UV-curing Performance

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Journal of Wuhan University of Technology(Materials Science) 2021年第6期36卷 942-948页

作者： HU Siwei HUANG Biwu chen weiqing School of Materials Science and Engineering Nanchang UniversityNanchang 330031China

A compound,3-ethyl-3-hydroxymethyloxetane(EHO),was synthesized with diethyl carbonate and trihydroxypropane as raw materials,3-ethyl-3-allylmethoxy oxetane(EAMO)was synthesized with EHO and allyl bromide,and 1,1,3,3,5,5-hexamethyl-1,5-bis[(3-ethyl-3-methoxyoxetane)propyl]trisiloxane(HMBEMOPTS)was synthesized with EAMO and 1,1,3,3,5,5-hexamethyltrisiloxane(HMTS).HMBEMOPTS is a novel UV-curable *** test of photo-DSC shows the photosensitivity of HMBEMOPTS is better than the ordinary oxetane,3-ethyl-3-[(3-ethyloxetan-3-yl)methoxymethyl]*** was mixed with bisphenol A type epoxy resin E-51 to prepare a cationic UV-curable system,and triarylsulfonium hexafluoroantimonate(UV-6976)was used as a cationic *** mechanical tests of coating films prove that when the mass fraction of HMBEMOPTS is 50%,the mechanical properties of the curing system are the *** impact strength of the UV-curable films is measured to be 40 kg·cm and the flexibility is 2 mm;the tensile strength and flexural strength of the prepared specimens are 20.74 MPa and 13.43 MPa,*** experimental results show that HMBEMOPTS can effectively improve photosensitivity and flexibility of the photosensitive resin.

关键词： oxetane siloxane photosensitive resin

Effect of Boron Content on the Microstructure and Magnetic Properties of Non-oriented Electrical Steels

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Journal of Wuhan University of Technology(Materials Science) 2015年第3期30卷 574-579页

作者：万勇 chen weiqing State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing School of Metallurgical Engineering Anhui University of Technology

The effects of boron content in the range of 0-0.0082 wt%, on the inclusion type, microstructurc, texture and magnetic properties of non-oriented electrical steels have been studied. After final annealing, the addition of excess boron（w（B0〉0.004 1 wt%） led to the formation of Fe2B particles. As boron content increased, grain size increased and reached a maximum in steel with 0.004 1 wt% boron. Furthermore, steel containing 0.004 1 wt% boron had the strongest { 100} fiber texture, Goss texture and the weakest { 111 } fiber texture among the five tested steels. Flux density firstly rapidly increased and then suddenly decreased with increasing boron content and reached a maximum in steel with 0.004 1 wt% boron. Conversely, core loss first sharply decreased and then abruptly increased with the increase of boron content and reached a minimum in steel containing 0.004 1 wt% boron. Steel containing 0.004 1 wt% boron obtained the best magnetic properties, predominantly through the development of optimum grain size and favorable texture.

关键词： boron non-oriented electrical steel grain size texture magnetic property

Association of β-fibrinogen gene-148C/T and-455G/A polymorphisms and coronary artery disease in Chinese population:A Meta analysis

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Science China(Life Sciences) 2008年第9期51卷 814-820页

作者： chen XiaoChao XU MingTong JIN LiZi chen Jian chen weiqing Department of Cardiology Fifth Affiliated HospitalSun Yat-sen UniversityZhuhai 519000China Department of Endocrinology Second Affiliated HospitalSun Yat-sen UniversityGuangzhou 510120China Department of Epidemiology Public Health CollegeSun Yat-sen UniversityGuangzhou 510080China

The purpose of our study was to evaluate the correlation between the β-fibrinogen gene –148C/T and –455G/A polymorphisms and susceptibility to coronary artery disease in the Chinese population using a meta–analytic approach. Eligible studies about this correlation were identified by searching the PubMed, EMBASE, and CNKI databases. Of the 13 identified, 7 (with 1488 cases and 1234 controls) involved the –148C/T polymorphism and 9 (with 1023 cases and 1081 controls) involved the –455G/A polymorphism. No publication bias was detectable and heterogeneity testing found significant differ-ences between the ORs for both groups of studies. The combined OR for the 7 studies on susceptibility to coronary artery disease in –148T allele carriers compared to the –148C/C wild-type homozygotes was 1.31 (95%CI: 0.94-1.84, P=0.11). The combined OR for the 9 studies on susceptibility to coronary artery disease in –455A allele carriers compared to the –455G/G wild-type homozygotes was 1.75 (95%CI: 1.24-2.46, P=0.001). Our results suggest the absence of an association between the β-fibrinogen gene –148C/T polymorphism and susceptibility to coronary artery disease and the possibility that –455G/A polymorphism (in particular, allele A) increases susceptibility to this disease in the Chinese population.

关键词： β-fibrinogen gene polymorphism coronary artery disease myocardial infarction Meta-analysis

Study on the Evaporation Kinetics of Zinc and Lead in Zn-Pb-Bearing Dust Pellets Mixed with Coal Powder

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Journal of Iron and Steel Research International 1999年第1期6卷 12-18页

作者： Wang Dongyan chen weiqing Zhou Rongzhang Wang Wenzhong Northeastern University University of Science and Technology Beijing

The study on the evaporation kinetics of zinc and lead in the pellets made of ZnPbbearing dust mixed with carbon ,in nitrogen atmosphere at the temperature range between 1 100 and 1 300 , shows that the reduction temperature has a significant effect on the evaporation rates of zinc and lead and that both the particle size of coal powder and the extra carbon content have no effect on the evaporation rates . The obtained activation energies for the evaporation of zinc and lead are 7942 kJ/mol and 8874kJ/mol respectively. The evaporation rate of zinc is controlled by the reaction between zinc oxide and CO while that of lead is controlled by lead volatilization and the diffusion of gaseous lead through gas boundary layer covering the surface of liquid lead.

关键词： ZnPbbearing dust pellets mixed with coal powder evaporation kinetics

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Synthesis of a Novel UV-curable Prepolymer Polypropyleneglycol Diglycidyl Ether Diacrylate

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Journal of Wuhan University of Technology(Materials Science) 2008年第4期23卷 495-498页

作者： HUANG Biwu HUANG Bofen DU Guoping chen weiqing School of Material Science and Engineering Nanchang University Nanchang 330031 China

A novel UV-curable prepolymer polypropyleneglycol diglycidyl ether diacrylate （PPGGEA） was synthesized by utilizing polypropyleneglycol diglycidyl ether （PPGGE） and acrylic acid （AA） as starting materials, N, N-dimethylbenzylamine as catalyst and p-hydroxyanisole as inhibitor. The optimum synthetic conditions were in the following： the concentration of N, N-dimethylbenzylamine was 0.80 wt% of reactants, the concentration of p-hydroxyanisole was 0.3 wt% of reactants, the reaction temperature was 90-110 ~C, and the molar ratio of PPGGE to AA was 1：2.2. Meanwhile, 1-hydroxycyclohexyl phenyl ketone of a UV-cured initiator was added to the synthesized PPGGEA to prepare a kind of UV-cured coating. The mechanical properties of the UV-cured films were determined, giving 29.99 MPa of tensile strength, 834.27 MPa of the Young＇s modulus and 5.66% of elongation at tear.

关键词： polypropyleneglycol diglycidyl ether diacrylate synthesis acrylic acid UV-curable prepolymer film

Synthesis of A Novel UV-curable Oligmer 1,4-cyclohexanedimethanol Glycidyl Ether Acrylate and Study on Its UV-curing Properties

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Journal of Wuhan University of Technology(Materials Science) 2014年第6期29卷 1283-1289页

作者：黄笔武 DENG Chong XU Qinchang chen weiqing ZOU Huaihua School of Materials Science and Engineering Nanchang University

A novel UV-curable oligmer 1,4-cyclohexanedimethanol glycidyl ether acrylate（CHDMGEA） was synthesized by utilizing 1,4-cyclohexanedimethanol glycidyl ether（CHDMGE） and acrylic acid（AA） as starting materials, triphenyl phosphine as catalyst and p-hydroxyanisole as inhibitor. The optimum synthetic conditions were that the concentration of triphenyl phosphine was 0.90% of reactants by weight, the concentration of p-hydroxyanisole was 0.20% of reactants by weight, the reaction temperature was 90-100 ℃, and the molar ratio of CHDMGE to AA was 0.5：1.1. The experimental results show that CHDMGEA is a kind of good UV-curable oligmer. The impact resistance of the UV-cured films with CHDMGEA as oligmer to prepare UV-curing coating was superior to that of the UV-cured films with bisphenol A diglycidyl ether diacrylate（BPGEA） as oligmer to prepare UV-curing coating.

关键词： 1 4-cyclohexanedimethanol glycidyl ether acrylate synthesis acrylic acid UV-curable oligmer film

Optimization of Extraction of Antioxidants from Turmeric(Curcuma longa L.) Using Response Surface Methodology

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Wuhan University Journal of Natural Sciences 2018年第1期23卷 63-69页

作者： LIU Caiqin chen weiqing WANG Nan JIN Jianchang College of Biology and Environment Engineering Zhejiang Shuren University

Turmeric is a spice widely used to enhance the taste and color of certain meats. We investigated the antioxidant capacities of turmeric ethanol soaking extracts by utilizing the scavenging properties of hydroxyl radical and 1,1-diphenyl-2-picrylhydrazyl（DPPH） free radical. The results showed that the optimum extraction parameters were： extraction time 4 h, sample-solvent ratio 1：84.12, solvent 72.34% ethanol solution, and water bath temperature 81.3 ℃. The optimum ethanol soaking extraction parameters were： extraction time 4 h, sample-solvent ratio 1：90.74, solvent 80.46% ethanol solution, water bath temperature 88.2 ℃. With these parameters, the hydroxyl radical scavenging rate and the DPPH free radical clearance of crude extracts from turmeric can reach about 93.78% and 40.69%, respectively. These results indicate that ethanol soaking extraction may be a useful method for extracting antioxidants from turmeric.

关键词： turmeric ethanol soaking extraction antioxidantactivity hydroxyl radical scavenging capacity 1,1-diphenyl-2-picrylhydrazyl(DPPH)scavenging capacity

AgOTf-Catalyzed Tandem Reaction of Oxabenzonorborna- dienes with Arylacetylenes

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Chinese Journal of Chemistry 2015年第10期33卷 1115-1118页

作者： Yongyun Zhou Shanshan Liu Hualei chen Jingchao chen weiqing Sun Sifeng Li Qingjing Yang Baomin Fan YMU-HKBU Joint Laboratory of Traditional Natural Medicine Yunnan Minzu University Kunming Yunnan 650500 China

A tandem isomerization/hydroarylation reaction of oxabenzonorbomadienes and arylacetylenes was realized by using AgOTf as catalyst. 1,1-Diarylethylenes could be easily generated as products in moderate to good yields ... 详细信息

关键词： silver tandem reaction catalyze 1,1-diarylethylene oxabenzonorbomadiene

Kinetics of Evaporation of Zn and Pb from Carbon-bearing Pellets Made of Dust Containing Zn-Pb-Fe Oxides

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International Journal of Minerals,Metallurgy and Materials 2000年第3期14卷 178-183页

作者： weiqing chen, Dongyan Wang, Rongzhang Zhou, Zongcai Lin (Metallurgy School, University of Science and Technology Beijing, Beijing 100083, China) Metallurgy School University of Science and Technology Beijing Beijing 100083 China

The influence of reduction temperature, size of coal powder and the carbon content on the evaporation rates of Zn and Pb in pellets made of ZnO-PbO-FeO bearing dust has been investigated between 1100-1300℃. The evaporation rate of Zn and Pb obtained from the experiments has been analyzed with kinetic models. The results show that the control step for evaporation of Zn is reduction reaction of ZnO by CO at the interface，and that the evaporation rate of Pb is controlled by the volatilization of reduction products, i.e. liquid lead. The overall apparent activation energies of Zn and Pb evaporation from the pellet are 79.42kJ/mol and 88.74kJ/mol respectively.

关键词： Zn-Pb-bearing dust carbon-containing pellet evaporation kinetics