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Chinese Chemical Letters 2003年第4期14卷 383-384页

作者： Guo Ying ZUO Hong Ping HE Bin gui wang Xin HONG Yi Ming HU Xiao Jiang HAO The State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650204 Kunming General Hospital Kunming 650032

A new diterpenoid, 15-O-acetylspiraminol (1), was isolated from the aerial parts of Spireae japonica L. f. var. ovalifolia. The structure was charaterized mainly based on spectral analysis.

关键词： Rosaceae Spireae japonica L. f. var. ovalifolia diterpenoids.

Grain refinement of commercial pure Al treated by Pulsed Magneto-Oscillation on the top surface of melt

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China Foundry 2015年第1期12卷 48-53页

作者： Dong Liang Zhu-yuan Liang Jie Sun Qi-jie Zhai wang gui David H.StJohn Shanghai Key Laboratory of Modern Metallurgy & Materials Processing Shanghai University Centre for Advanced Materials Processing and Manufacturing The University of Queensland

Commercial pure Al can be refined by Pulsed Magneto-Oscillation(PMO) treatment applied via a plate induction coil above the top surface of the melt. The proportion of the equiaxed zone area increases with decreasing Height to Diameter(H/D) ratios from 3.5 to1.8 and further to 1.0. Meanwhile, it increases and then decreases with increasing peak current for the three kinds of ingots with H/D ratios of 3.5, 1.8 and 1.0, respectively. However, when the H/D ratio decreases to 0.44, the area proportion of equiaxed zone can reach the maximum value with a lower peak current. FEA software simulation indicates that smaller H/D ratio results in larger current density, electromagnetic force and convection on the top surface of the melt, favoring nucleation and subsequent grain formation. Through evaluating Joule heating effect by PMO, it was found that the proper amount of Joule heating benefits grain refinement. Excessive Joule heating can reduce the size of the equiaxed zone and change the growth morphology of the grains.

关键词： grain refinement casting process nucleation and growth finite element(FE) simulation pulsed magneto-oscillation(PMO)

Near-field 3D imaging approach combining MJSR and FGG-NUFFT

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Journal of Systems Engineering and Electronics 2019年第6期30卷 1096-1109页

作者： wang Shuzhen FANG yang ZHANG Jin’gang LUO Mingshi LI Qing School of Computer Science and Technology Xidian UniversityXi’an 710071China School of Electronics and Information Northwestern Polytechnical UniversityXi’an 710072China Institute of Optics and Electronics Chinese Academy of SciencesChengdu 610209China College of Materials Sciences and Opto-Electronic Technology University of Chinese Academy of SciencesBeijing 100049China College of Computer Science Xi’an Shiyou UniversityXi’an 710065China The Fourth Research Institute of Telecommunications Technology Co. LtdXi’an 710061China

A near-field three-dimensional(3 D)imaging method combining multichannel joint sparse recovery(MJSR)and fast Gaussian gridding nonuniform fast Fourier transform(FGGNUFFT)is proposed,based on a perfect combination of the compressed sensing(CS)theory and the matched filtering(MF)*** approach has the advantages of high precision and high efficiency:multichannel joint sparse constraint is adopted to improve the problem that the images recovered by the single channel imaging algorithms do not necessarily share the same positions of the scattering centers;the CS dictionary is constructed by combining MF and FGG-NUFFT,so as to improve the imaging efficiency and memory ***,a near-field 3 D imaging model of joint sparse recovery is constructed by combining the MF-based imaging ***,FGG-NUFFT and reverse FGG-NUFFT are used to replace the interpolation and Fourier transform in MF-based imaging methods,and a sensing matrix with high precision and high efficiency is constructed according to the traditional imaging ***,a fast imaging recovery is performed by using the improved separable surrogate functionals(SSF)optimization algorithm,only with matrix and vector ***,a 3 D imagery of the near-field target is obtained by using both the horizontal and the pitching interferometric phase *** paper contains two imaging models,the only difference is the sub-aperture method used in inverse synthetic aperture radar(ISAR)*** to traditional CS-based imaging methods,the proposed method includes both forward transform and inverse transform in each iteration,which improves the quality of *** experimental results show that,the proposed method improves the imaging accuracy by about O(10),accelerates the imaging speed by five times and reduces the memory usage by about O(10~2).

关键词： interference imaging joint sparse recovery compressed sensing(CS) matching filtering(MF) fast Gaussian gridding nonuniform fast Fourier transform(NUFFT) near-field 3D imaging

Influence of Surface-functionalized Graphene Oxide on the Cell Morphology of Poly(methyl methacrylate) Composite

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Journal of Materials Science & Technology 2015年第5期31卷 463-466页

作者： Yuwei wang Xia Liao Yong Luo Qi yang Guangxian Li College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan University Analytical and Testing Center Sichuan University

The surface chemistry of filler is closely related to the structure and morphology of nanocomposite *** the property of filler is widely used to control the cell structures and functionalize the composite ***-functionalized graphene oxide（GO-ODA） was prepared by grafting octadecylamine（ODA） on the surface of graphene oxide（GO） to make the filler disperse better in the nanocomposites and have a strong interfacial interaction with polymer ***（methyl methacrylate）（PMMA）/GO-ODA nanocomposite foams were obtained by solution blending and foamed using supercritical carbon dioxide（scCO2）.Compared to neat PMMA and PMMA/GO samples,the PMMA/GO-ODA nanocomposite foams showed improved cell structures with smaller size,higher cell density and more homogeneous distribution,which should be attributed to the heterogeneous nucleation caused by well-dispersed GO-ODA *** work not only improved the compatibility and interfacial interaction of GO with polymer matrix but also indicated that the modified GO sheets can act as ideal filler to control the cell density,size and size distribution efficiently.

关键词： Graphene oxide Functionalization Supercritical car

Prokaryotic Expression and Polyclonal Antibody Preparation of PRL3

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Chemical Research in Chinese Universities 2007年第6期23卷 697-700页

作者： SHEN Xing-gui LI Wan-nan wang Jing JIANG Yi-qun LI Qing-shan FU Xue-qi Edmond H. Fischer Signal Transduction Laboratory College of Life Sciences Jilin University Changchun 130021 P. R. China

Phosphatase of regenerating liver 3 （ PRL3 ）, which belongs to the superfamily of protein tyrosine phosphatases （PTPs）, represents a group of low molecular weight PTPs that participate in tumorigenesis and metastasis processes. Presented here are the results of cloning, prokaryotic expression, purification, and polyclonal antibody preparation of PRL3. To obtain a specific polyclonal antibody against PRL3, the authors have prepared GST-PRL3 to immunize rabbits and purify an anti-PRL3 polyclonal antibody by negative selection affinity columns. Western blot analysis shows that the anti-PRL3 polyclonal antibody has a specific binding ability with PRL3 protein. The anti-PRL3 polyclonal antibody provides a good tool to further study the function of PRL3.

关键词： PRL3 Prokaryotic expression Polyclonal antibody

Effect of long reaction distance on gas composition from organic-rich shale pyrolysis under high-temperature steam environment

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International Journal of Coal Science & Technology 2024年第3期11卷 102-119页

作者： Lei wang Rui Zhang Guoying wang Jing Zhao Dong yang Zhiqin Kang yangsheng Zhao Key Laboratory of In-Situ Property Improving Mining of Ministry of Education Taiyuan University of TechnologyTaiyuan030024China The In-Situ Steam Injection Branch of State Center for Research and Development of Organic-Rich Shale Exploitation Taiyuan University of TechnologyTaiyuan030024China College of Mining Engineering Taiyuan University of TechnologyTaiyuan030024China School of Energy Science and Engineering Henan Polytechnic UniversityJiaozuo454002China

When high-temperature steam is used as a medium to pyrolyze organic-rich shale,water steam not only acts as heat transfer but also participates in the chemical reaction of organic matter pyrolysis,thus affecting the generation law and release characteristics of gas *** this study,based on a long-distance reaction system of organic-rich shale pyrolysis via steam injection,the effects of steam temperature and reaction distance on gas product composition are analyzed in depth and compared with other pyrolysis *** advantages of organic-rich shale pyrolysis via steam injection are then *** volume concentration of hydrogen in the gas product obtained via the steam injection pyrolysis of organic-rich shale is the highest,which is more than 60%.The hydrogen content increases as the reaction distance is extended;however,the rate of increase changes *** the reaction distance from 800 to 4000 mm increases the hydrogen content from 34.91%to 69.68%and from 63.13%to 78.61%when the steam temperature is 500℃ and 555℃,***,the higher the heat injection temperature,the smaller the reaction distance required to form a high concentration hydrogen pyrolysis environment(hydrogen concentration>60%).When the steam pyrolysis temperature is increased from 500℃ to 555℃,the reaction distance required to form a high concentration of hydrogen is reduced from 3800 to 800 *** with the direct retorting process,the volume concentration of hydrogen obtained from high-temperature steam pyrolysis of organic-rich shale is 8.82 and 10.72 times that of the commonly used Fushun and Kivite furnaces,*** pyrolysis of organic-rich shale via steam injection is a pyrolysis process in a hydrogen-rich environment.

关键词： Steam temperature Pyrolysis gas Hydrogen-rich Reaction distance Direct retorting

Photoluminescence of carbon quantum dots:coarsely adjusted by quantum confinement effects and finely by surface trap states

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Science China Chemistry 2018年第4期61卷 490-496页

作者： Zexi Liu Hongyan Zou Ni wang Tong yang Zhewei Peng Jian wang Na Li Chengzhi Huang Key Laboratory of Luminescent and Real-Time Analytical Chemistry(Southwest University) Ministry of EducationCollege of Pharmaceutical ScienceSouthwest UniversityChongqing 400715China Chongqing Key Laboratory of Biomedical Analysis(Southwest University) Chongqing Science&Technology CommissionCollege of Chemistry and Chemical EngineeringSouthwest UniversityChongqing 400715China Beijing National Laboratory for Molecular Sciences Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of EducationInstitute of Analytical ChemistryCollege of Chemistry and Molecular EngineeringPeking UniversityBeoing 100871China

Photoluminescence(PL) mechanism of carbon quantum dots(CQDs) remains controversial up to now even though a lot of approaches have been made. In order to do that, herein a PL color ladder from blue to near infrared of CQDs with the absolute quantum yields higher than 70% were prepared via a one-pot hydrothermal synthesis route and separated by silica gel ***-correlated single photon counting measurements suggest that the electron transition takes in effect in the PL progress of the crystalline core-shell structured CQDs, and the PL properties could be coarsely adjusted by tuning the size of the crystalline carbon core owing to quantum confinement effects, and finely adjusted by changing the surface functional groups consisted shell owing to surface trap states,respectively. Both coarse and fine adjustments of PL, as optical and photoelectrical characterizations and density-functional theory(DFT) calculations have demonstrated, make it possible for top-level design and precise synthesis of new CQDs with specific optical properties.

关键词： carbon quantum dots quantum confinement effects surface trap states electron transition

Numerical simulation of the stress-strain curve and the stress and strain distributions of the titanium-duplex alloy

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Rare Metals 2008年第5期27卷 463-467页

作者： ZHAO Xiqinga ZANG Xinliang wang Qingfeng Park Joongkeun yang Qingxiang Key Laboratory of Metastable Materials Science ＆ Technology Yanshan University Qinhuangdao 066004 China Department of Materials Science and Engineering Korea AdvancedInstitute of Science and Technology Taejon 305-701 South Korea

The stress-strain curve of an α-β Ti-8Mn alloy was measured and then it was calculated with finite element method （FEM） based on the stress-strain curves of the single α and β phase alloys. By comparing the calculated stress-strain curve with the measured one, it can be seen that they fit each other very well. Thus, the FE model built in this work is effective. According to the above mentioned model, the distributions of stress and strain in the α and β phases were simulated. The results show that the stress gradients exist in both α and β phases, and the distributions of stress are inhomogeneous. The stress inside the phase is generally higher than that near the interface. Meanwhile, the stress in the α phase is lower than that in the β phase, whereas the strain in the α phase is higher than that in the β phase.

关键词： titanium alloy stress-strain curve numerical simulation finite element method

Legionella pneumophila-mediated host posttranslational modifications

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Journal of Molecular Cell Biology 2023年第5期15卷 7-20页

作者： Yi yang Ligang Mei Jing Chen Xiaorong Chen Zhuolin wang Lu Liu Aimin yang School of Life Sciences Chongqing UniversityChongqing 401331China

Legionella pneumophila is a Gram-negative bacterium ubiquitously present in freshwater environments and causes a serious type of pneumonia called Legionnaires’*** infections,*** releases over 300 effector proteins into host cells through an Icm/Dot type IV secretion system to manipulate the host defense system for survival within the ***,certain effector proteins mediate posttranslational modifications(PTMs),serving as useful approaches exploited by *** to modify host *** effectors catalyze the addition of host protein PTMs,while others mediate the removal of PTMs from host *** this review,we summarize *** effector-mediated PTMs of host proteins,including phosphorylation,ubiquitination,glycosylation,AMPylation,phosphocholination,methylation,and ADP-ribosylation,as well as dephosphorylation,deubiquitination,deAMPylation,deADP-ribosylation,dephosphocholination,and *** describe their molecular mechanisms and biological functions in the regulation of bacterial growth and Legionella-containing vacuole biosynthesis and in the disruption of host immune and defense machinery.

关键词： Legionella pneumophila bacterial effector posttranslational modification host-pathogen interaction Legionellacontaining vacuole pathogenesis host defense system