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Copper-Catalyzed Si-H Bond Insertion Polymerization for Synthesis of Optically Active Polyesters Containing Silicon

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Chinese Journal of Chemistry 2022年第1期40卷 21-27页

作者： xiao-Yong Zhai xiao-Qing Wang Bo Wu Yong-gui Zhou State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalianLiaoning 116023China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

The synthesis and characterization of chiral polymers with diverse structure remain a long-term challenging research ***,a copper-catalyzed enantioselective insertion of carbene into Si-H bond was applied to polycondensation,giving a new type of optically active degradable polyesters containing Si-C bond in the main *** polymerization features mild condition,broad substrate scope,excellent yields and *** diols could be obtained via reduction of optically active *** analysis indicated these chiral polyesters exhibit good thermal stability.

关键词： Polymerization Insertion Asymmetric catalysis Optically active polyesters Copper

Correlation Between Microstructure and Mechanical Properties of 2219-T8 Aluminum Alloy Joints by VPTIG Welding

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Acta Metallurgica Sinica(English Letters) 2017年第5期30卷 438-446页

作者： Lan-Qiang Niu xiao-Yan Li liang Zhang xiao-Bo liang Mian Li College of Materials Science and Engineering Beijing University of TechnologyBeijing 100124China

In this study, 2219-T87 aluminum alloys were butt welded by the double-pass tungsten inert gas arc welding process. And the softening behavior of fusion zone（FZ） and heat-affected zone（HAZ） was evaluated with the analysis of welding temperature field, grain size, alloying element distribution and precipitates evolution. Results show that the two FZs are almost the weakest regions in the joint, where the microhardness value is 76 and 78 HV, respectively. Microhardness of the HAZ generally grows along with increasing distance from fusion line except a valley value at the distance of about 4.5 mm. The mean grain size of two FZs is about 74.4 and 79.2 lm, whereas 41.5, 44.9 and 43.4 lm for the two measured HAZs and base metal（BM）, respectively. There is about 60.4% and 54.2% Cu consumed in the coarse whitish particles of FZs that have little strengthening effect, while the percentage is about 24.6% of BM that is almost the same as HAZ. A large number of strengthening phases h0 distribute dispersively in BM, whereas hardly any precipitates exist in FZ and HAZ adjacent to FZ. So the coarsening of grain size, reduction and segregation of alloying element content, and the precipitate evolution are regarded as the main causes of softening in FZ, while the precipitate evolution is the main factor of softening in HAZ.

关键词： 2219-T87 Aluminum alloy TIG welding Fusion zone Heat-affected zone Softening behavior

Up-conversion of Nd^(3+)/Yb^(3+)/Tm^(3+) tri-doped CaTeO3 compound under excitation of 808 nm

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Rare Metals 2021年第4期40卷 1008-1013页

作者： Zhong-Qiang Ye Si-Guo xiao xiao-liang Yang School of Physics and Optoelectronics Xiangtan UniversityXiangtan 411105China

Nd^(3+)/Yb^(3+)/Tm^(3+) tri-doped CaTeO3 compounds were prepared by a solid-state reaction *** blue up-conversion(UC) luminescence at around 476 nm,which corresponds to the Tm^(3+):^(1)G_(4)→^(3)H_(6) transition,was observed under 808-nm *** Nd^(3+)→Yb^(3+)→Tm^(3+) energy transfer process was responsible for the strong blue up-conversion emission in the tri-doped *** Tm^(3+) blue up-conversion emission intensity was strongly dependent on the concentrations of Yb^(3+) and Nd^(3+).The possible up-conversion mechanisms for the Nd^(3+)/Yb^(3+)/Tm^(3+) tri-doped CaTeO_(3) phosphor are discussed,based on the Nd^(3+) and Yb^(3+) concentration-dependent UC spectra,near-infrared luminescence spectra and luminescence decay curves.

关键词： Up-conversion Tellurite 808 nm Energy transfer

Hydroxylation of Benzene to Phenol via Hydrogen Peroxide in Hydrophilic Triethylammonium Acetate Ionic Liquid

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Chemical Research in Chinese Universities 2011年第3期27卷 503-507页

作者： HU xiao-ke ZHU liang-fang GUO Bin LIU Qiu-yuan LI gui-ying HU Chang-wei Key Laboratory of Green Chemistry and Technology Ministry of Education College of Chemistry Sichuan University Chengdu 610064 P. R. China

A new Fenton-like system in a medium of hydrophilic triethylammonium type of ionic liquid（IL） was used for the hydroxylation of benzene to phenol. The triethylammonium acetate（[Et3NH][CH3COO]） IL exhibited retardation performance for the decomposition of H2O2 and protection performance for the further oxidation of phenol, thus the yield and selectivity to phenol were promoted greatly. The acidity of the system was proved to be an important factor for the selectivity to phenol. The utilization of H2O2 and the selectivity to phenol, as well as the Turnover number（TON） of the catalyst were effectively enhanced by a benzene-[Et3NH][CH3COO] bi-phase system. The catalyst with [Et3NH][CH3COO] IL was recycled with stable catalytic performance.

关键词： Hydrophilic Ionic liquid Fenton-like Hydroxylation

Dynamic properties of polyurethane foam adhesive-reinforced gravels

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Science China(Technological Sciences) 2021年第3期64卷 535-547页

作者： LIU Ping MENG MinQiang xiao Yang LIU HanLong YANG gui School of Civil Engineering Ludong UniversityYantai 264025China School of Civil Engineering Chongqing UniversityChongqing 400045China Key Laboratory of New Technology for Construction of Cities in Mountain Area Chongqing UniversityChongqing 400045China College of Civil and Transportation Engineering Hohai UniversityNanjing 210098China Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing 210098China

Polyurethane foam adhesive(PFA)has been introduced as an alternative stabilizer in geotechnical applications because PFA can improve the engineering characteristics of soil by filling the pore space and generating adhesive bonding among the ***,the dynamic properties of PFA-reinforced soils are not well *** analyze the dynamic characteristics of PFA-reinforced gravels,a series of cyclic triaxial tests were carried out to investigate the shear modulus and damping ratio of PFA-reinforced gravels,and to determine the corresponding effects of the PFA content,confining pressure,consolidation stress ratio and loading *** results showed that the shear modulus increased,and the damping ratio decreased as the PFA content,confining pressure and consolidation stress ratio *** contrast,the effect of the loading frequency,which ranged from 0.05 to 1 Hz,was negligible.A modified hyperbolic empirical model can consider the effect of the PFA content on the maximum shear modulus and predict the relationship between the normalized shear modulus and the normalized shear strain was ***,the upper and lower bounds of the damping ratio were also proposed.

关键词： polyurethane foam adhesive gravel shear modulus damping ratio cyclic triaxial test

Light Subgraphs in the Family of 1-Planar Graphs with High Minimum Degree

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Acta Mathematica Sinica,English Series 2012年第6期28卷 1155-1168页

作者： Xin ZHANG gui Zhen LIU Jian liang WU School of Mathematics Shandong University

A graph is 1-planar if it can be drawn in the plane so that each edge is crossed by at most one other edge. In this paper, it is shown that each 1-planar graph with minimum degree 7 contains a copy of K2 V （K1 ∪ K2） with all vertices of degree at most 12. In addition, we also prove the existence of a graph K1 V （K1∪K2） with relatively small degree vertices in 1-planar graphs with minimum degree at least 6.

关键词： 1-Planar graph lightness height discharging

GuanxinⅤRelieves Ventricular Remodeling by Inhibiting Inflammation:Implication from Virtual Screening,Systematic Pharmacology,Molecular Docking,and Experimental Validation

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Chinese Journal of Integrative Medicine 2023年第12期29卷 1077-1086页

作者： liang Bo ZHANG xiao-xiao GU Ning Department of Cardiology Nanjing Hospital of Chinese Medicine Affiliated to Nanjing University of Chinese MedicineNanjing(210022)China Department of Nephrology the Key Laboratory for the Prevention and Treatment of Chronic Kidney Disease of ChongqingChongqing Clinical Research Center of Kidney and Urology DiseasesXinqiao HospitalArmy Medical University(Third Military Medical University)Chongqing(400037)China School of Chinese Medicine School of Integrated Chinese and Western MedicineNanjing University of Chinese MedicineNanjing(210046)China

Objective:To reveal the anti-inflammatory mechanism of GuanxinⅤ,which is prescribed for ventricular remodeling in clinical ***:GuanxinⅤ-,ventricular remodeling-,and inflammationrelated targets were obtained through an integrated strategy of virtual screening and systematic pharmacology,and then the shared targets were visualised with a Venn ***Ⅴnetwork and the protein-protein interaction network were drawn,and enrichment analysis was ***,the main results obtained from the integrated strategy were validated by molecular docking and in vivo ***:A total of 251,11,425,and 15,246 GuanxinⅤ-,ventricular remodeling-,and inflammation-related targets were acquired,***,211 shared targets were considered to contribute to the mechanism of ventricular remodeling treated by GuanxinⅤ.Guanxin network and the protein-protein interaction network were drawn,and enrichment analysis showed some cardiovascular-related biological processes and signaling *** docking revealed that the GuanxinⅤ-derived compounds could align with key *** in vivo experiments proved that GuanxinⅤreverses ventricular remodeling by inhibiting ***:GuanxinⅤrelieves ventricular remodeling by regulating inflammation,which provides new ideas for the anti-ventricular remodeling mechanism of GuanxinⅤ.

关键词： GuanxinⅤ Chinese medicine ventricular remodeling inflammation

Influence of age on seven putative prostate tumor markers： a cohort study in Chinese men

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Asian Journal of Andrology 2017年第4期19卷 463-467页

作者： Wei-gui Sun Chao-Zhao liang Qi-Chuan Zheng xiao-Wu HU Zhi-Zhen Li Ping Wu Research Institute of Urology Ma'anshan People's Hospital Affiliated to Anhui Medical University Ma'anshan 243000 China Department of Urology The First Affiliated Hospital of Anhui Medical University Hefei 230000 China The Center of Clinical Molecular Biology Laboratory Ma'anshan 243000 China

The accuracy and sensitivity of prostate-specific antigen （PSA） for prostate cancer diagnosis is often poor; however, the reasons for its inaccuracy have rarely been investigated, especially with respect to age. In this study, 476 healthy males, aged 10-89 years, were stratified into eight age groups, and levels of seven markers were determined： total PSA （tPSA）, free PSA （fPSA）, %fPSA, isoform [-2]proPSA （p2PSA）, p2PSA/tPSA, %p2PSA, and the prostate health index （PHI）. Both tPSA and fPSA levels increased with age. The tPSA level was highest （1.39 ng m1-1） at 70-79 years; %fPSA was highest （0.57 ng ml-1） at 10-19 years; and %p2PSA was lowest （18.33 ng ml-1） at 40-49 years. Both p2PSA and p2PSA/tPSA had relatively flat curves and showed no correlation with age （P = 0.222）. PHI was a sensitive age-associated marker （P 〈 0.05）, with two peaks and one trough. The coverage rates and radiance graphs of PHI and %p2PSA were more distinctive than those of tPSA and the other markers. In subjects older than 69 years, PHI and %p2PSA both began to decrease, approximately 10 years earlier than the decrease in tPSA. Our results suggest that the clinical diagnosis of prostate cancer using PSA should be investigated more comprehensively based on patient age. Moreover, %p2PSA and PHI could be considered as earlier markers that may be more suitable than PSA alone.

关键词： age factors diagnosis prostate cancer tumor marker

Controlling multiple optomechanically induced transparency in the distant cavity-optomechanical system

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Chinese Physics B 2021年第3期30卷 314-319页

作者： Rui-Jie xiao gui-Xia Pan xiao-Ming Xiu College of Physical Science and Technology Bohai UniversityJinzhou 121013China School of Science Anhui University of Science and TechnologyHuainan 232001China

We theoretically investigate a two-cavity optomechanical system in which each optical cavity couples to a mechanical resonator via radiation pressure force,and the two optical cavities couple to each other via a distant *** study shows that the multiple optomechanically induced transparency can be observed from the output field at the probe *** number and width of the transparent windows can be tuned by the classical driving power *** also analyze the distance of the two outermost transparency windows,which shows a linear relation with the parameters Pl andλ.Our approach is feasible for controlling multipartite induced transparency,which represents a valuable step towards quantum networks with photonic and phononic circuits.

关键词： optomechanical system optomechanically induced transparency optical mode