检索结果-南通市图书馆

Microstructure and mechanical properties of high-strength low alloy steel by wire and arc additive manufacturing

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2020年第7期27卷 933-942页

作者： yi-li dai Sheng-fu Yu An-guo Huang Yu-sheng Shi State Key Laboratory of Material Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhan 430074China

A high-building multi-directional pipe joint(HBMDPJ)was fabricated by wire and arc additive manufacturing using high-strength low-alloy(HSLA)*** microstructure characteristics and transformation were observed and *** results show that the forming part includes four *** solidification zone solidifies as typical columnar crystals from a molten *** complete austenitizing zone forms from the solidification zone heated to a temperature greater than 1100℃,and the typical columnar crystals in this zone are difficult to *** partial austenitizing zone forms from the completely austenite zone heated between Ac1(austenite transition temperature)and1100℃,which is mainly equiaxed *** several thermal cycles,the partial austenitizing zone transforms to the tempering zone,which consistes of fully equiaxed *** the solidification zone to the tempering zone,the average grain size decreases from 75 to20μ*** mechanical properties of HBMDPJ satisfies the requirement for the intended application.

关键词： wire and arc additive manufacturing high strength low alloy steel microstructure inclusions fine grain ferrite mechanical properties

Research on hydration of phenylacetylene assisted with additives in near-critical water

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2011年第4期22卷 393-396页

作者： Shuang li Yong Juan Chang Yu Wang li yi dai Shanghai Key Laboratory of Green Chemistry and Chemical Process Department of Chemistry East China Normal UniversityShanghai 200062China

The hydration of phenylacetylene in near-critical water,assisted with additives（NaHSO4,ZnCl2,FeCl3）,has been successfully conducted with temperature and residence time ranges of 220-300℃and 60-180 min,*** results showed the catalytic ability is *** maximum yield of product acetophenone was 96.68%at 260℃,120 *** on the results found,a possible mechanism of hydration of phenylacetylene in near-critical water was proposed.

关键词： Hydration Phenylacetylene Additives Near-critical water Mechanism

Ionic liquids as efficient phase-transfer catalysts for the solid base-promoted monoalkylation of diethyl malonate

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2007年第3期18卷 279-282页

作者： Hui Sun Juan li Xiao Chen Cai Dong Jiang li yi dai Department of Chemistry East China Normal University Shanghai 200062 China

Ionic liquids （ILs） based on 1,3-dialkylimidazolium and tetraalkylammonium cations were employed as a series of efficient, environmentally benign phase-transfer catalysts （PTCs） for the base-promoted monoalkylation of diethyl malonate. The influence of various heterogeneous bases on yields was studied. Good yields and high selectivity were obtained. Solvent-free, mild reaction condition, short reaction time, and easy purification were the merits of this method. The catalytic system （IL-hase） could also be recycled after the extraction of products with ether.

关键词： Ionic liquids Phase-transfer catalysis Diethyl malonate Alkylation

Application of Et_3NHCl-AlCl_3 Ionic liquid as an Initiator in Cationic Copolymerization of 1, 3-Pentadiene with Styrene

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2006年第1期17卷 117-120页

作者： Yuan Yuan WANG Hui SUN Juan li Dong JIANG li yi dai Center for the Chemistry of Ionic liquids East China Normal University （E.C.N.U） Shanghai 200062

The random copolymer poly （1, 3-pentadiene-co-styrene） formed through cationic copolymerization using the ~ethylamine hydrochloride and hydrous aluminium chloride （Et3NHCl-AlCl3） room temperature ionic liquid as initiating agent in toluene was analyzed using IR spectra in conjunction with gel permeation chromatography （GPC）. The room temperature ionic liquid was found to have high initiatic activity for copolymerization.

关键词： Et3NHCl-AlCl3 ionic liquid 1 3-pentadiene styrene cationic copolymerization.

Doebner condensation in ionic liquids [Bmim]BF_4 and [Bpy]BF_4 to synthesize α,β-unsaturated carboxylic acid

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2009年第3期20卷 279-282页

作者： Dong Jiang Yuan Yuan Wang Yan Nan Xu li yi dai Shanghai Key Laboratory of Green Chemistry and Chemical Processes Department of Chemistry East China Normal University Shanghai 200062 China

Ionic liquids [Bmim]BF4 and [Bpy]BF4 were employed as environmentally benign media in Doebner condensation to synthesize α, β-unsaturated carboxylic acid. The good results showed that [Bmim]BF4 and [Bpy]BF4 were efficient media for Doebner condensation, which could be recycled easily. The highest yields could reach 93% and 90% in [Bmim]BF4 and [Bpy]BF4, respectively.

关键词： Ionic liquid Doebner condensation α, β-Unsaturated carboxylic acid Decarboxylation

Preparation of fructone catalyzed by water-soluble Brφnsted acid ionic liquids

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2007年第1期18卷 24-26页

作者： Yuan Yuan Wang Rong Wang liang Chun Wu li yi dai Departmem of Chemistry East China Normal University Shanghai 200062 China Department of Chemistry Shanghai Normal University Shanghai 200234 China

Fructone （2-methyl-2-ethylacetoacetate-1, 3-dioxolane）, a flavouring material, has been synthesized from ethyl acetoacetate and glycol using five water-soluble Brφnsted acid ionic liquids as catalysts for the first time. The used Brφnsted acid ionic liquids include [Hmim]Tfa, [Hmim]Tsa, [Hmim]BF4, [Bmim]HSO4, [Bmim]H2P04, and [Hmim]BF4 showed the highest catalytic activity for the preparation of fructone. After reaction, the product could be isolated from the reaction system automatically, and the ionic liquid could be directly reused without dehydration.

关键词： Fructonc Water-soluble Brφnsted acid ionic liquids Catalyst

Convenient synthesis and application of novel bi-SO_3H-functionalized ionic liquids based on piperazinium

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2012年第9期23卷 1031-1034页

作者： Yuan Yuan Wang Yue Tong Wu Kun liu li yi dai Department of Chemistry East China Normal UniversityChinaShanghai 200062

In this article, series of novel bi-SOaH-functionalized ILs were synthesized using simple, efficient and economic procedure. Hammer method had been used to determine the acidity order of these ionic liquids, and the acidifies of bi-SOaH-functionalized ILs were stronger than that of traditional single-SOaH-functionalized ILs. Their catalytic activities in the synthesis of N-（3-phenyl）-3- oxo-1-（phenylpropyl）acetamide were investigated and they were consistent with their acidities.

关键词： Novel bi-SO3H-functionalized ionic liquids Synthesis Acidity characterization Hammett function Catalytic activity

A catalyst-free novel synthesis of diethyl carbonate from ethyl carbamate in supercritical ethanol

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2014年第10期25卷 1395-1398页

作者： li-Cai Zhao Zhi-Qiang Hou Chun-Ze liu Yuan-Yuan Wang li-yi dai Department of Chemistry East China Normal University

Diethyl carbonate has been synthesized via the alcoholysis of ethyl carbamate in supercritical ethanol under catalyst-free *** influences of various parameters such as reaction temperature,reaction time,reaction pressure,ethanol/ethyl molar ratios and reaction loading volume on the yield of DEC were studied *** experimental results indicated that the alcoholysis of ethyl carbamate was greatly improved in supercritical *** optimal reaction conditions were as follows：a reaction temperature of 573 K,a reaction time of 30 min,a reaction pressure of 13.2 MPa,an ethanol/ethyl carbamate molar ratio of 10 and a reactor loading volume of 285 μL *** optimal yield of DEC was 22.9%.

关键词： Supercritical ethanol Diethyl carbonate Ethyl carbamate Alcoholysis

First Binary Mixture Ionic liquids Containing EMIMBr and IM

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2003年第6期14卷 634-636页

作者： li yi dai Chun Yan HUA Sheng Rong YE Yong Kui SHAN Ming Yuan HE Center for the Chemistry of Ionic liquid East China Normal UniversityShanghai 200062

A new series of binary mixture ionic liquids comprising 1-ethyl-3-methylimidozalium bromide (EMIMBr) and imidazole (IM) have been synthesized. The melting points of the ionic liquids vary with the different content of IM while they still keep satisfactory conductivity and viscosity. According to the analysis of its phase diagram, the eutectic point is about 16.5C with the mass percentage of IM 29%.

关键词： Ionic liquid binary mixture phase diagram.