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Esterification and Chemoselective Synthesis of R-Tetrahydrothiazo-2-thione-4-carboxylic Esters Catalyzed by TiCl_4

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Chemical Research in Chinese Universities 2007年第4期23卷 430-432页

作者： SHANG Yan-mei LI Jing song zhi-guang LI Ye-zhi HUANG Hua-min College of Chemistry School of Public Health Key Laboratory for Supermolecular Structure and Materials of Ministry of Education Jilin University Changchun 130021 P. R. China

A series of esters of R-tetrahydrothiazo-2-thione-4-carboxylic acid [ R-TTCA ] was synthesized by direct esterifica- tion of R-TTCA with alcohols（CH3OH, C2H5OH, n-C3HTOH, i-C3HTOH, n-C4H9OH, sec-C4H9OH） in the presence of TiCl4 as the catalyst at room temperature without using any other solvent or dehydrant in high yields, 91.6%-99.1% for primary alcohols and 55%- 80% for secondary alcohols. The catalyst has a strong chemoselec-tive activity for the esterification of primary alcohols with R-TTCA in the presence of secondary alcohols. Owing to high yield, high chemoselectivity, and mild conditions used, this is an efficient method for the esterification of prima-ry alcohols with R-TTCA.

关键词： R-Tetrahydrothiazo-2-thione-4-carboxylic acid TICl4 Chemoselectivity Esterification

Design, Synthesis and Antitumor Activity in vitro of a Series of 3-Arylcoumarins

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Chemical Research in Chinese Universities 2013年第6期29卷 1125-1128页

作者： LIU zhi-hui LI De-jun JIANG Dan XIAO Chuan song zhi-guang JIN Ying-hua Department of Prosthodontics School of StomatologyJilin University Changchun 130021 P.R.China Department of Organic Chemistry College of Chemistry Jilin University Changchun 130021 P.R.China Key Laboratory for Molecular Enzymology and Engineering Ministry of EducationJilin University Changchun 130012 P.R.China

A new series of 7-substituted 3-arylcoumarins was designed, synthesized and evaluated as novel antitumor agents in vitro. It was found that several compounds of them exhibit activity in vitro against SK-HEP-l（hepatocellular carcinoma）, HepG2（hepatocellular carcinoma） and SGC7901（gastric carcinoma） cell lines to some extent. Moreover, compounds 5a, 5b, 6a and 6b have better activity against HeLa（cervical carcinoma） cell and their half maximal inhibitory concentration（IC50） values are less than 10μmol/L.

关键词： 3-Arylcoumarin Antitumor activity Structure modification

Synthesis and Crystal Structure of (R)-4-Hydroxymethyl-2-thioxo Thiazolidine and Its Asymmetric Catalysis

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Chemical Research in Chinese Universities 2009年第1期25卷 43-46页

作者： LI Jing SHANG Yan-mei XIAO Chuan song zhi-guang LI Ye-zhi HUANG Hua-min College of Chemistry Jilin University School of Public Health Jilin University Changchun 130021 P. R. China Key Laboratory for Supramoleeular Structure and Materials of Ministry of Education Jilin University Changehun 130012 P. R. China

（R）-4-Hydroxymethyl-2-thioxo thiazolidine as a new chiral catalyst in the asymmetric addition of diethylzinc to benzaldehyde was synthesized from （R）-4-hydroxymethyl-2-thioxo thiazolidine carboxylic acid and its crystal structure was determined by X-ray diffraction method. The compound was crystallized in the orthorhombic system, space group P212121 with unit cell dimensions a=0.67253（12） nm; b=0.89164（17） nm; c=1.06146（19） nm, volume 0.6365（2） nm^3; Z=4, calculated denisity 1.557 Mg/m^3; absorption coefficient 0.733 mm^-1; F（000）=312. The X-ray crystal structure analysis reveals that the compound has a thione group.

关键词： Crystal structure Asymmetric (R)-4-Hydroxymethyl-2-thioxothiazolidine

Esterification and Selective Esterification in the Presence of TiCl_4

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Chemical Research in Chinese Universities 2007年第6期23卷 669-673页

作者： SHANG Yan-mei LI Jing ZHANG Ping song zhi-guang LI Ye-zhi HUANG Hua-min College of Chemistry Jilin University Changchun 130021 P. R. China School of Public Health Jilin University Changchun 130021 P. R. China Key Laboratory for Supermolecular Structure and Materials of Ministry of Education Jilin University Changchun 130012 P. R. China

A series of carboxylic acids was esterified to the corresponding esters with TICl4 as catalyst at room temperature, in high yields. This catalyst was highly effective for the selective esterification of primary alcohols with carboxylic acids, in the presence of secondary alcohols, and for the selective esterification of saturated acid with alcohol in the presence of conjugated acid or aromatic acid. On account of the high yield, high chemoselectivity, mild condition, and being free of other dehydrants, this is an efficient method.

关键词： Esterification Chemoselectivity TiCl4

Association of (S)-Isoserine Derivatives and 2,2,4-Trimethyl-3-hydroxy-4-cyclohexenecarboxylate

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Chemical Research in Chinese Universities 2007年第1期23卷 18-21页

作者： WANG Lei ZHENG Qing-chuan song zhi-guang FANG Wei-shuo LI Ye-zhi HUANG Hua-min College of Chemistry State Key Laboratory of Theoretical and Computational Chemistry Jilin University Changchun 130021 P. R. China Institute of Materia Medica Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100050 P. R. China

Two novel compounds（4a and 4b） were obtained by the association of 2,2,4-trimethyl-3-hydroxy-5-cyclohexenecarboxylate with （S） -isoserine derivatives. The space location of the hydroxyl group of compound 1 was identified via the formation of lactone 6. Fe2 （SO4）3·xH2O was used as the catalyst for the synthesis of lactone 6. The carboxyl group was selectively protected with diazomethane. All the products were characterized via ^1H NMR and mass spectra. The Docking study showed that the associations have the potential therapeutic use of DPP-Ⅳ inhibitor.

关键词： (S) -Isoserine 2,2,4-Trimethyl-3-hydroxy-d-cyclohexenecarboxylate Association DPP- Ⅳ

Full waveform inversion based on hybrid gradient

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Petroleum Science 2024年第3期21卷 1660-1670页

作者： Chuang Xie zhi-Liang Qin Jian-Hua Wang Peng song Heng-guang Shen Sheng-Qi Yu Ben-Jun Ma Xue-Qin Liu Qingdao Innovation and Development Base Harbin Engineering UniversityQingdao266000ShandongChina Qingdao Innovation and Development Center Harbin Engineering UniversityQingdao266000ShandongChina CNOOC Research Institute Co. Ltd.Beijing100028China College of Marine Geoscience Ocean University of ChinaQingdao266100ShandongChina Weihai Sunfull Geophysical Exploration Equipment Co. Ltd.Weihai264209ShandongChina

The low-wavenumber components in the gradient of full waveform inversion(FWI)play a vital role in the stability of the ***,when FWI is implemented in some high frequencies and current models are not far away from the real velocity model,an excessive number of low-wavenumber components in the gradient will also reduce the convergence rate and inversion *** solve this problem,this paper firstly derives a formula of scattering angle weighted gradient in FWI,then proposes a hybrid *** hybrid gradient combines the conventional gradient of FWI with the scattering angle weighted gradient in each inversion frequency band based on an empirical formula derived *** weighted hybrid mode,we can retain some low-wavenumber components in the initial lowfrequency inversion to ensure the stability of the inversion,and use more high-wavenumber components in the high-frequency inversion to improve the convergence *** results of synthetic data experiment demonstrate that compared to the conventional FWI,the FWI based on the proposed hybrid gradient can effectively reduce the low-wavenumber components in the gradient under the premise of ensuring inversion *** also greatly enhances the convergence rate and inversion accuracy,especially in the deep part of the *** the field marine seismic data experiment also illustrates that the FWI based on hybrid gradient(HGFWI)has good stability and adaptability.

关键词： Full waveform inversion Hybrid gradient Scattering angle weighted Low-wavenumber component

Grain-boundary segregation and grain growth in nanocrystalline substitutional solid solution alloys

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Journal of Materials Science & Technology 2024年第1期168卷 239-249页

作者： Fawei Tang Chao Hou Hao Lu zhi Zhao Xiaoyan song Faculty of Materials and Manufacturing Key Laboratory of Advanced Functional MaterialsMinistry of Education of ChinaBeijing University of TechnologyBeijing 100124China

A model for describing solute segregation at grain boundaries has been developed for substitutional solid solution alloys,which integrates multiple factors from atomic to microstructural scales.A concept of mo-lar Gibbs free energy of segregation was introduced to evaluate the segregating capability of the solute elements in a closed system,through which the influences of grain boundary structure,grain size,ma-terial composition,and external conditions were *** on the evaluation of various energy forms related to solute segregation and grain growth processes,the nature of the thermal stabilization of nanograin structures by solute segregation was disclosed.A criterion for the destabilization of nanostruc-tures,which is determined by the competition of the change rates between the molar Gibbs free energy of segregation and the total energy of grain boundaries with grain size,has been *** study provided guideline to achieve high-temperature stability of nanograin structures of solid solution alloys even for the weakly segregating nanocrystalline systems.

关键词： Substitutional solid solution Grain boundary segregation Thermal stabilization Solute concentration Grain size

Neutron irradiation influence on high-power thyristor device under fusion environment

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Nuclear Science and Techniques 2024年第4期35卷 65-81页

作者： Wei Tong Hua Li Meng Xu zhi-Quan song Bo Chen School of Electrical Engineering and Automation Hefei University of TechnologyHefei 230009China Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China

Because of their economy and applicability,high-power thyristor devices are widely used in the power supply systems for large fusion *** high-dose neutrons produced by deuterium–tritium(D–T)fusion reactions are irradiated on a thyristor device for a long time,the electrical characteristics of the device change,which may eventually cause irreversible *** this study,with the thyristor switch of the commutation circuit in the quench protection system(QPS)of a fusion device as the study object,the relationship between the internal physical structure and external electrical parameters of the irradiated thyristor is ***,a series of targeted thyristor physical simulations and neutron irradiation experiments are conducted to verify the accuracy of the theoretical *** addition,the effect of irradiated thyristor electrical characteristic changes on the entire QPS is studied by accurate simulation,providing valuable guidelines for the maintenance and renovation of the QPS.

关键词： Fusion device Neutron irradiation effects Thyristor Quench protection

Crystallization of RE_(2)(OH)_(2)CO_(3)SO_(4)·nH_(2)O as a new family of layered hydroxides(RE=Gd-Lu lanthanides and Y),derivation of RE_(2)O_(2)SO_(4),photoluminescence and optical thermometry

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Journal of Rare Earths 2024年第8期42卷 1496-1506,I0003页

作者： Fan Li Zhenqi song zhiyuan Pan Sihan Feng Qi Zhu Ji-guang Li Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang110819China Research Center for Functional Materials National Institute for Materials ScienceTSsukuboaIbaraki3050044Japan

Layered rare-earth hydroxides(LREHs) draw wide research interest because of their peculiar crystal structure,rich interlayer chemistry and abundant functionality of the RE element,but are limited to the two categories of RE_(2)(OH)_(5)A·nH_(2)O(A:typical of Cl^(-)or NO_(3)^(-)) and RE_(2)(OH)_(4)SO_(4)·nH_(2)*** the other hand,rare-earth oxysulfates(RE_(2)O_(2)SO_(4)) have attracted attention due to their properties of large-capacity oxygen storage,low-temperature magnetism and luminescence,but their preparation procedure mostly involves toxic SO_(x) gases and/or complicated *** this work,RE_(2)(OH)_(2)CO_(3)SO_(4)·nH_(2)O as a new family of LREHs(RE=Gd-Lu lanthanides and Y) were produced via hydrothermal reaction,from which phase-pure RE_(2)O_(2)SO_(4) was derived via subsequent annealing at 800℃ in air without the involvement of SO_(x),The compounds were thoroughly characterized to reveal the intrinsic influence of lanthanide contraction(RE^(3+) radius) on crystal structure,thermal behavior(dehydroxylation/decarbonation/desulfurization),vibrational property and crystallite *** analyzing the photoluminescence of Eu^(3+) and Sm^(3+)in the Gd_(2)O_(2)SO_(4) typical host it is found that the 617 nm(Eu^(3+),λ_(ex)=275 nm) and 608 nm(Sm^(3+),λ_(ex)=407 nm) main emissions can retain as high as ^(7)9.6% and 85.5%of their room-temperature intensities at 423 K,with activation energies of ~0.19 and 0.21 eV for thermal quenching,*** also indicates that both the phosphors have the potential for optical temperature sensing via the fluorescence intensity ratio(FIR) technology,whose maximum relative sensitivity reaches -2.70%/K for Eu^(3+)and 1.73%/K for Sm^(3+) at 298 K.

关键词： Layered hydroxide RE_(2)O_(2)SO_(4) Luminescence Optical temperature sensing Rare earths