检索结果-南通市图书馆

Hydrogenation behaviors and characteristics of bulk Ti-6Al-4V alloy at different isothermal temperatures

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2019年第12期38卷 1131-1135页

作者： Long Pan Chun-Ming Wang Su-Fen Xiao yun-gui Chen School of Aeronautics and Astronautics Sichuan UniversityChengdu 610065China College of Materials Science and Engineering Sichuan UniversityChengdu 610065China

The bulk Ti-6Al-4V alloy was hydrogenated at the temperature range of 723-973 K,and the hydrogen absorption characteristics and hydrogen absorption kinetics were *** results show that there are two types of hydrogen absorption characteristics at different *** hydrogen content decreases,and the time reaching reaction equilibrium is shorten with the isothermal hydrogenation temperature ***,the mechanism of the hydrogen absorption kinetics is different at different *** incubation period exists at the initial hydrogen absorption stage below 823 K,and K(a2)(the reaction rate constant of Stage 2)>>K(a1)(the reaction rate constant of Stage 1).And there is no incubation period over 823 K,K(a1)>>K(a2).

关键词： Bulk Ti-6Al-4V alloy Hydrogen content Hydrogen absorption kinetic Temperature

Synthesis of Trihydrocarbyltin Chloride Containing Silicon and Crystal Structure of (p-Cl-C_6H_4Me_2SiCH_2)_3SnCl

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2002年第3期18卷 277-279页

作者： ZHONG gui yun LIU Hua XIE Qing lan Institute of Elemento organic Chemistry Nankai UniversityTianjin 300071P.R.China

A series of trihydrocarbyltin chlorides containing silicon was synthesized. The acaricidal activity was determined and the structure activity relationship was tried to be found out with the hydrophobic parameter.

关键词： Organotin and organosilicon Acaricidal activity Structure activity relationship

Isolation, purification and structural characterization of a water-soluble polysaccharide HM41 from Halenia elliptica ***

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2016年第6期27卷 979-983页

作者： Chun-Lan Liu Yang Li gui-yun Xu Ya-Shuang Li College of Life and Environmental Science Minzu University of ChinaBeijing 100081China Beijing Engineering Research Center of Food Environment and Public Health Minzu University of ChinaBeijing 100081China Institute of Chemistry Chinese Academy of SciencesBeijing 100080China

A water-soluble polysaccharide, HM（41）, was obtained from Halenia elliptica D. Don by acidic ethanol fractionation and gel filtration. Its homogeneity was confirmed by chromatography using multiple systems. HM（41） was composed of rhamnose（Rha）, arabinose（Ara）, xylose（Xyl）, mannose（Man）,galactose（Gal）, glucose（Glc） with a molar ratio of 1.0：5.5：1.8：3.0：9.4：21. The average molecular weight of HM（41） was approximately 1.17 ＊ 10~4. Periodate oxidation, Smith degradation, methylation and GC, IR,NMR, XRD, GC–MS analysis were used for the structural analysis of HM（41）. Its main chain was composed mainly of β-（1→4）Gal, β-（1→4）Glc and β-（1→6）Glc. β-（1 →4）Gal were substituted at 6-O and on average there were 14 branches among 23 main chain residues;（1→ 4）Glc had no branch;（1→6）Glc were substituted at 3-O and on average there were 9 branches among 14 main chain residues. The side chain was composed of（1→3,6）-Rha,（1→4）/（1→5）-Ara,（1 →4）/（1→5）-Xyl,（1→4,6）-Man and（1→2）-Glc. The terminal residue was composed of Ara, Xyl, Man, Gal, and Glc. Then, we demonstrated that HM and HM（41） had strong scavenging activities in vitro hydroxyl. Overall, HM and HM（41） may have potential applications in the antioxidants for medical and food industry.

关键词： Halenia elliptica D.Don Polysaccharide Isolation purification Structural analysis Antioxidant activities

Synthesis, Resolution, and Enantiomeric Purity Assay of 2-n-Butylbutanedioic Acid 4-t-Butyl Esters

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2006年第5期22卷 584-588页

作者： ZHANG Da-tong TANG Li-da DUAN gui-yun ZHAO gui-long XU Wei-ren MENG Li-juan WANG Jian-wu School of Chemistry and Chemical Engineering Shandong University Jinan 250100 P. R. China The Pharmaceutical Research Institute of Tianjin Tianjin 300193 P. R. China

Racemic 2-n-butylbutanedioic acid 4-t-butyl esters were synthesized from methyl hexanoate and t-butyl α-iodoacetate via alkylation and subsequently selective hydrolyzation. The （R）-and （S）-2-n-butylbutanedioic acid 4-t-butyl esters were obtained by the resolution of the above-mentioned racemic compounds with（S）-（ - ） or（R）-（＋）-α- methylbenzylamine, respectively. The e.e. values of the two optical active products were determined to be above 99% by HPLC after the formation of two pairs of diastereoisomers with（R）-（＋）-α-methylbenzylamine and（S）- phenylalanine methyl ester.

关键词： Methyl hexanoate 4-t-Butyl 2-n-butylbutanedioic acid Resolution e.e. Value

Corrosion Resistance of MgO-C Based Refractory to Slag Containing Titania

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2004年第1期11卷 1-4页

作者： LIU Qing-cai SUN Ya-li DU yun-gui CHEN Deng-fu Chongqing University

The interaction between the slag containing titanium oxides(TiO2of 2.0 %-20.0%)and a MgO-C based refractory was investigated by immersion *** relationship between TiO2 content in slag and corrosion rate of the refractory was *** microstructure and compositions of the corroded refractory were analyzed by SEM and X-ray *** corrosion mechanism of MgO-C based refractory in the slag containing titanium was proposed,and the effects of TiO2 content,slag basicity(ωCaO/ωSiO2)and temperature in molten bath on the corrosion rate of the refractory were obtained.

关键词： slag titanium oxide MgO-C based refractory corrosion

同方期刊数据库

Analytical model of tilted driver–pickup coils for eddy current nondestructive evaluation

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2018年第3期27卷 125-131页

作者： Bing-Hua Cao Chao Li Meng-Bao Fan Bo Ye gui-yun Tian School of Information and Control Engineering China University of Mining and TechnologyXuzhou 221116China jiangsu Key Laboratory of Mine Mechanical and Electrical Equipment China University of Mining and TechnologyXuzhou 221116China School of Mechatronic Engineering China University of Mining and TechnologyXuzhou 221116China Faculty of Information Engineering and Automation Kunming University of Sciance and TechnologyKunming 650500China School of Electrical and Electronic Engineering Newcastle UniversityNewcastle upon Tyne NE17RUUK

A driver-pickup probe possesses better sensitivity and flexibility due to individual optimization of a *** is fre-quently observed in an eddy current(EC)array *** this work,a tilted non-coaxial driver-pickup probe above a multilayered conducting plate is analytically modeled with spatial transformation for eddy current nondestructive ***,the core of the formulation is to obtain the projection of magnetic vector potential(MVP)from the driver coil onto the vector along the tilted pickup coil,which is divided into two key *** first step is to make a projection of MVP along the pickup coil onto a horizontal plane,and the second one is to build the relationship between the pr,ojected MVP and the MVP along the driver ***,an analytical model for the case of a layered plate is established with the reflection and transmission theory of electromagnetic *** calculated values from the resulting model indicate good agreement with those from the finite element model(FEM)and experiments,which validates the developed analytical model.

关键词： nondestructive evaluation eddy currents tilted coils analytical model

A simulation package—SASAL for X-ray and EUV spectroscopy of astrophysical and laboratory plasmas

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2014年第10期14卷 1351-1366页

作者： gui-yun Liang Fang Li Fei-Lu Wang Yong Wu Jia-Yong Zhong Gang Zhao Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of Sciences Data Center for High Energy Density Physics Institute of Applied Physics and Computational Mathematics

For the laboratory astrophysics community, those spectroscopic modeling codes extensively used in astronomy, e.g. Chianti, AtomDB, Cloudy and Xstar, cannot be directly applied to analyzing laboratory measurements due to their discrepancies from astrophysical cases. For example, plasma from an electron beam ion trap has an electron energy distribution that follows a Gaussian profile, instead of a Maxwellian one. The laboratory miniature for a compact object produced by a laser-driven implo- sion shows a departure from equilibrium, that often occurs in celestial objects, so we setup a spectral analysis system for astrophysical and laboratory （SASAL） plasmas to act as a bridge between them, which benefits the laboratory astrophysical community.

关键词： atomic data -- line formation -- plasmas -- X-rays general

Functional characterization of a low-density lipoprotein receptor in the lepidopteran model,Bombyx mori

在线全文

学校读者我要写书评

暂无评论

Insect Science 2022年第5期29卷 1262-1274页

作者： gui-yun Li Xiao-Jing Liu Gang-Qi Fang Jie Yang Shuai Zhan Mu-Wang Li Jiangsu Key Laboratory of Sericultural Biology and Biotechnology School of BiotechnologyJiangsu University of Science and TechnologyZhenjiangJiangsuChina CAS Key Laboratory of Insect Developmental and Evolutionary Biology CAS Center for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghaiChina The Key Laboratory of Silkworm and Mulberry Genetic Improvement Ministry of AgricultureSericultural Research InstituteChinese Academy of Agricultural SciencesZhenjiangJiangsuChina CAS Center for Excellence in Biotic Interactions University of Chinese Academy of SciencesBeijingChina

The growth and development of metabolous insects are mainly regulated by ecdysone and juvenile *** a member of the low-density lipoprotein receptor(LDLR)family,megalin(mgl)is involved in the lipoprotein transport of cholesterol which is an essential precursor for the synthesis of *** extensive studies in mammals,the function of mgl is still largely unknown in *** this study,we characterize the function of mgl in the silkworm Bombyx mori,the model species of *** find that mgl is broadly present in the genomes of lepidopteran species and evolved with divergence between lepidopterans and *** expression pattern suggests a ubiquitous role of mgl in the growth and development in the *** further perform clustered regularly interspaced palindromic repeats(CRISPR)/CRISPR-associated protein 9-based mutagenesis of Bmmgl and find that both the development and the silk production of the silkworm are seriously affected by the disruption of *** results not only explore the function of mgl in Lepidoptera but also add to our understanding of how cholesterol metabolism is involved in the development of insects.

关键词： Bombyx mori cholesterol CRISPR/Cas9 development megalin silkworm

Self-microemulsifying drug delivery system for improving the bioavailability of huperzine A by lymphatic uptake

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Pharmaceutica Sinica B 2017年第3期7卷 353-360页

作者： Fang Li Rongfeng Hu Bin Wang yun gui Gang Cheng Song Gao Lei Ye Jihui Tang Anhui University of Chinese Medicine Hefei 230038China National Chinese Medicinal Materials Products Quality Supervision and Inspection Center(Anhui) Bozhou 236800China Key Laboratory of Xin'an Medicine Ministry of Education Hefei 230038China Anhui“115”Xin'an Traditional Chinese Medical Research&Development Innovation Team Hefei 230038China Anhui Province Key Laboratory of R&D of Chinese Medicine Hefei 230038China School of Pharmacy Anhui Medical UniversityHefei 230022China

Huperzine A(Hup-A) is a poorly water-soluble drug with low oral bioavailability. A selfmicroemulsifying drug delivery system(SMEDDS) was used to enhance the oral bioavailability and lymphatic uptake and transport of Hup-A. A single-pass intestinal perfusion(SPIP) technique and a chylomicron flow-blocking approach were used to study its intestinal absorption, mesenteric lymph node distribution and intestinal lymphatic uptake. The value of the area under the plasma concentration–time curve(AUC) of Hup-A SMEDDS was significantly higher than that of a Hup-A suspension(P <0.01).The absorption rate constant(K_a) and the apparent permeability coefficient(P_(app)) for Hup-A in different parts of the intestine suggested a passive transport mechanism, and the values of K_a and P_(app) of Hup-A SMEDDS in the ileum were much higher than those in other intestinal segments. The determination of Hup-A concentration in mesenteric lymph nodes can be used to explain the intestinal lymphatic absorption of Hup-A SMEDDS. For Hup-A SMEDDS, the values of AUC and maximum plasma concentration(C_(max)) of the blocking model were significantly lower than those of the control model(P<0.05). The proportion of lymphatic transport of Hup-A SMEDDS and Hup-A suspension were about 40% and 5%,respectively, suggesting that SMEDDS can significantly improve the intestinal lymphatic uptake and transport of Hup-A.

关键词： Huperzine A Self-microemulsion Drug delivery systems SMEDDS Bioavailability Single-pass intestinal perfusion Lymphatic transport