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Method for Improving Transverse Wall Thickness Precision of Seamless Steel Tube Based on Tube Rotation

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Journal of Iron and Steel Research International 2015年第10期22卷 924-930页

作者： Yong-zheng JIANG hua-ping tang State Key Laboratory of High Performance Complex Manufacturing Central South University

The tube rotation method （TRM） refers to the rotational movement of steel tube about its axis as well as translation in rolling direction in stretch reducing rolling process. The influence of the TRM on transverse wall thickness precision of seamless steel tube was studied. Thickness distribution of the TRM was obtained by superimposing the thickened amount of single pass rolling. Results show that the TRM can effectively improve the evenness of thickness distribution. In order to analyze the influence mechanism of the TRM, the finite element method was adopted to simulate the thickness distribution in stretch reduction process. Results show that the TRM changes the roundtrip flow between two fix places of conventional stretch reducing and inhibits the directional accumulation of metal. In addition, the TRM has a correction effect on thickness cusp. All these advantages of the TRM help to improve the transverse wall thickness precision of seamless steel tube.

关键词： seamless tube stretch reducing transverse unevenness tube rotation method

Effect of Cooling Rate on Microstructure and Mechanical Properties of Sand-Casted ***-0.6Mn-0.25Ce Alloy

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Acta Metallurgica Sinica(English Letters) 2019年第12期32卷 1549-1564页

作者： hua-ping tang Qu-Dong Wang Chuan Lei Kui Wang Bing Ye Hai-Yan Jiang Wen-Jiang Ding National Engineering Research Center of Light Alloy Net Forming Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240China

This study examines the relationship among cooling rate,microstructure and mechanical properties of a sand-casted Al-5.0 Mg-0.6 Mn-0.25 Ce(wt%)alloy subjected to T4 heat treatment(430℃×12 h+natural aging for 5 days),and the tested alloys with wall thickness varying from 5 to 50 mm were *** results show that as the cooling rate increases from0.22 to 7.65 K/s,the average secondary dendritic arm spacing(SDAS,λ2)decreases from 94.8 to 27.3μ*** relation between SDAS and cooling rate can be expressed by an equation:λ2=53.0 ***,an increase in cooling rate was shown not only to reduce the amount of the secondary phases,but also to promote the transition from Al10 Mn2 Ce toα-Al24(Mn,Fe)6Si2 *** tests show that as the cooling rate increases from 0.22 to 7.65 K/s,the ultimate tensile strength(UTS)increases from 146.3 to 241.0 MPa and the elongation(EL)increases sharply from 4.4 to 12.2%for the ascast *** of UTS and EL with SDAS were determined,and both the UTS and EL increase linearly with(1/λ2)0.5and that these changes can be explained by strengthening *** eutectic Al3Mg2 phases were dissolved during T4 treatment,which in turn further improve the YS,UTS and ***,the increment percent of YS,UTS and EL is affected by the cooling rate.

关键词： Al-Mg-Mn cast alloys Cooling rate Microstructure Al10Mn2Ce Mechanical properties

Advancements in S-scheme heterojunction materials for photocatalytic environmental remediation

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Journal of Materials Science & Technology 2024年第2期169卷 182-198页

作者： Changliang Nie Xiaohan Wang ping Lu Yukun Zhu Xin Li hua tang School of Environmental Science and Engineering State Key Laboratory of Bio-fibers and Eco-textilesQingdao UniversityQingdao266071China Institute of Biomass Engineering Key Laboratory of Energy Plants Resource and UtilizationMinistry of Agriculture and Rural AffairsSouth China Agricultural UniversityGuangzhou510642China School of Environmental Science and Engineering Shandong UniversityQingdao266237China

Recently,S-scheme heterojunctions have gained considerable attention in the field of photocatalytic environmental remediation as their potential to achieve efficient spatial charge separation coupled with strong redox ***,this review provides an overview of the current state-of-the-art in the development of S-scheme-based photocatalysts for the purification of environmental *** review first covers the fundamentals of heterogeneous photocatalysis for environmental ***,an introduction to the background,mechanism,design principles,and characterization techniques of S-scheme heterojunctions is ***,the review presents a comparison and summary of using various S-scheme photocatalysts for the removal of several target pollutants,such as bacteria,heavy metals,nitrogen oxides,antibiotics,and ***,the modification strategies of S-scheme heterojunction photocatalysts are also ***,a brief discussion of the challenges and prospects associated with S-scheme photocatalytic systems is demonstrated.

关键词： S-scheme heterojunctions Photocatalyst Pollutant Environmental remediation

Effects of Solution Treatment on the Microstructure,Tensile Properties,and Impact Toughness of an Al–5.0Mg–3.0Zn–1.0Cu Cast Alloy

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Acta Metallurgica Sinica(English Letters) 2021年第1期34卷 98-110页

作者： hua-ping tang Qu-Dong Wang Colin Luo Chuan Lei Tian-Wen Liu Zhong-Yang Li Kui Wang Hai-Yan Jiang Wen-Jiang Ding National Engineering Research Center of Light Alloy Net Forming and State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240China Schulich School of Engineering University of CalgaryCalgaryABCanada

This study investigates the eff ect of solution treatment(at 470°C for 0–48 h)on the microstructural evolution,tensile properties,and impact properties of an Al–5.0Mg–3.0Zn–1.0Cu(wt%)alloy prepared by permanent gravity *** results show that the as-cast microstructure consists ofα-Al dendrites and a network-like pattern of T-Mg32(AlZnCu)49 *** of the T-phases were dissolved within 24 h at 470℃;and a further prolonging of solution time resulted in a rapid growth ofα-Al *** transformation from the T-phase to the S-Al2CuMg phase was discovered in this *** the tensile properties and impact toughness increased quickly,reached a maximum peak value,and decreased gradually as the solution treatment *** impact toughness is more closely related to the elongation,and the relationship between impact toughness and elongation appears to obey an equation:IT=8.43 *** optimal solution treatment at 470℃for 24 h,this alloy exhibits excellent mechanical properties with the ultimate tensile strength,yield strength,elongation and impact toughness being 431.6 MPa,270.1 MPa,19.4%and 154.7 kJ/m^(2),which are comparable to that of a wrought Al–6.0 Mg–0.7 Mn alloy(5E06,a 5 xxx aluminum alloy).Due to its excellent comprehensive combination of mechanical properties,this cast alloy has high potential for use in components which require medium strength,high ductility and high toughness.

关键词： Al–Mg–Zn–Cu cast alloys T-Mg32(AlZn)49 phase S-Al2CuMg phase Impact toughness Mechanical properties

Nuclear charge radius predictions by kernel ridge regression with odd-even effects

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Nuclear Science and Techniques 2024年第2期35卷 94-102页

作者： Lu tang Zhen-hua Zhang Mathematics and Physics Department North China Electric Power UniversityBeijing 102206China Hebei Key Laboratory of Physics and Energy Technology North China Electric Power UniversityBaoding 071000China

The extended kernel ridge regression(EKRR)method with odd-even effects was adopted to improve the description of the nuclear charge radius using five commonly used nuclear *** are:(i)the isospin-dependent A^(1∕3) formula,(ii)relativistic continuum Hartree-Bogoliubov(RCHB)theory,(iii)Hartree-Fock-Bogoliubov(HFB)model HFB25,(iv)the Weizsacker-Skyrme(WS)model WS*,and(v)HFB25**** the last two models,the charge radii were calculated using a five-parameter formula with the nuclear shell corrections and deformations obtained from the WS and HFB25 models,*** each model,the resultant root-mean-square deviation for the 1014 nuclei with proton number Z≥8 can be significantly reduced to 0.009-0.013 fm after considering the modification with the EKRR *** best among them was the RCHB model,with a root-mean-square deviation of 0.0092 *** extrapolation abilities of the KRR and EKRR methods for the neutron-rich region were examined,and it was found that after considering the odd-even effects,the extrapolation power was improved compared with that of the original KRR *** strong odd-even staggering of nuclear charge radii of Ca and Cu isotopes and the abrupt kinks across the neutron N=126 and 82 shell closures were also calculated and could be reproduced quite well by calculations using the EKRR method.

关键词： Nuclear charge radius Machine learning Kernel ridge regression method

Identifying the best common factor model via exploratory eactor analysis

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 24-33页

作者： HE Bao-hua tang Rui TAGN Qi-yi School of Big Data Fuzhou University of International Studies and TradeFuzhou 350202China School of Mathematics Sun Yat-Sen UniversityGuangzhou 510275China Department of Computer Science University of BathUK Institute of Insect Science Zhejiang UniversityHangzhou 310058China.

Currently,there is no solid criterion for judging the quality of the estimators in factor *** paper presents a new evaluation method for exploratory factor analysis that pinpoints an appropriate number of factors along with the best method for factor *** proposed technique consists of two steps:testing the normality of the residuals from the fitted model via the Shapiro-Wilk test and using an empirical quantified index to judge the quality of the factor *** are presented to demonstrate how the method is implemented and to verify its effectiveness.

关键词： factor analysis Shapiro-Wilk normality residuals

Semisynthesis of homogeneous spike RBD glycoforms from SARS-CoV-2 for profiling the correlations between glycan composition and function

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National Science Review 2024年第2期11卷 145-154页

作者： Farong Ye Cheng Li Feng-Liang Liu Xinliang Liu Peng Xu Rong-hua Luo Wenping Song Yong-tang Zheng Tianlei Ying Biao Yu ping Wang Center for Chemical Glycobiology Frontiers Science Center for Transformative Molecules Zhangjiang Institute for Advanced Study School of Chemistry and Chemical Engineering Shanghai Jiao Tong University MOE/NHC/CAMS Key Laboratory of Medical Molecular Virology Shanghai Frontiers Science Center of Pathogenic Microorganisms and Infection Shanghai Institute of Infectious Disease and BiosecurityShanghai Engineering Research Center for Synthetic ImmunologySchool of Basic Medical Sciences Shanghai Medical College Fudan University Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences/Key Laboratory of Bioactive Peptides of Yunnan Province Center for Biosafety Mega-Science Kunming Institute of ZoologyChinese Academy of Sciences State Key Laboratory of Bioorganic and Natural Products Chemistry Center for Excellence in Molecular Synthesis Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shenzhen Research Institute of Shanghai Jiao Tong University

Vaccines have been the primary remedy in the global fight against coronavirus disease 2019（COVID-19）.The receptor-binding domain（RBD） of the spike protein, a critical viral immunogen, is affected by the heterogeneity of its glycan structures and relatively low immunogenicity. Here, we describe a scalable synthetic platform that enables the precise synthesis of homogeneously glycosylated RBD, facilitating the elucidation of carbohydrate structure–function relationships. Five homogeneously glycosylated RBDs bearing biantennary glycans were prepared, three of which were conjugated to T-helper epitope(Tpep) from tetanus toxoid to improve their weak immune response. Relative to natural HEK293-derived RBD, synthetic RBDs with biantennary N-glycan elicited a higher level of neutralising antibodies against SARS-CoV-2 in mice. Furthermore, RBDs containing Tpepelicited significant immune responses in transgenic mice expressing human angiotensin-converting enzyme 2. Our collective data suggest that trimming the N-glycans and Tpepconjugation of RBD could potentially serve as an effective strategy for developing subunit vaccines providing efficient protection.

关键词： peptide ligation glycosylation glycoprotein

(Parallel) kinetic resolution of 3,3-disubstituted indolines via organocatalyzed reactions with azodicarboxylates

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Science China Chemistry 2024年第3期67卷 973-980页

作者： Qianwen Jiang Dekun Zhang Mengyao tang hua Liu Xiaoyu Yang School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China

A novel kinetic resolution(KR) method has been developed for 3,3-disubstituted indolines, whose catalytic asymmetric synthesis remains a significant challenge in organic synthesis. The key to the success of this KR protocol lies in the utilization of chiral phosphoric acid-catalyzed triazane formation reaction with azodicarboxylates, which enables the enantioselective synthesis of various substituted indolines bearing C3-quaternary stereocenters with good to high enantioselectivities(with sfactors up to 70). Moreover, an intriguing parallel kinetic resolution(PKR) has been developed by combining triazane formation and dehydrogenation reactions using different azodicarboxylates. Experimental studies have provided insight into the mechanism of this PKR reaction, demonstrating stereoselectivity in both triazane formation and dehydrogenation steps, favoring the opposite enantiomers. The large-scale synthesis and diverse derivatizations of the products, particularly the imine groupcontaining 3H-indoles, demonstrate the value of these(P)KR methods.

关键词： asymmetric organocatalysis kinetic resolution 3 3-disubstituted indolines azodicarboxylate triazanes

Trace element compositions of pyrite and stibnite:implications for the genesis of antimony mineralization in the Yangla Cu skarn deposit,Northwestern Yunnan,China

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Acta Geochimica 2024年第3期43卷 535-554页

作者： ping Pan Xinfu Wang Bo Li Guo tang Zuopeng Xiang Faculty of Land and Resource Engineering Kunming University of Science and TechnologyKunming 650093China Kunming Metallurgy College Kunming 650033China School of Earth Science Yunnan UniversityKunming 650500China Kunming Prospecting Design Institute of China Nonferrous Metals Industry Co. LtdKunming 650051China

The Yangla Cu skarn deposit is located in the central part of the Jinshajiang Suture Zone,southwest China,with a total reserve of 150 Mt Cu@1.03%.The newly discovered antimony orebodies at the depth of Yangla are strictly controlled by the stratum,structure,and lithology,which are lenticular and vein-like within the marble fracture zone,which can provide a window into multistage miner-alization and ore genesis at *** can be divided into three types,Cu–Pb–Zn(skarn)pyrite,galena,and sphalerite,Cu(porphyry)chalcopyrite and pyrite,and Sb(hydrothermal)stibnite and *** mineral assem-blages were stibnite+pyrite+calcite+quartz±minor scheelite in antimony *** study presents quantitative measurements of the trace element compositions of pyrite and stibnite from the Yangla antimony *** of pyrite with electron probe microanalysis(EPMA)showed enrichment in Co,Ni,Sb,As,and Mo,and deficit in its S and Fe contents when compared to the stoichiometric con-centrations of S and Fe in *** Sb-related pyrite may belong to sedimentary-reworked genesis and may be modi-fied by hydrothermalfluids,thereby presenting a certain dif-ference(i.e.,crystal morphology,texture,and chemical com-position)compared to the skarn and porphyry Cu-related pyrite in the Yangla Cu skarn *** of stibnite with EPMA and inductively coupled plasma-mass spectrom-etry showed enrichment in As,Pb,Sn,Pb,Cu,and Zn,and presented much higher Sb contents and slightly lower S con-tents when compared to the stoichiometric concentrations of Sb and S in *** analysis of the stibnite trace elements showed correlations for the elemental pairs Cu–Pb,As–Sb,and Sn–Pb,and the coupled substitution equations Sb^(3+)↔Cu^(+)+Pb^(2+),Sb^(3+)↔As^(3+),and Sn^(2+)↔Pb^(2+)may be the major factors governed the incorporating Cu,Pb,As and Sn within the ***,this study preliminary shows that the antimony mineralization may belong to a car-bonate replacement h

关键词： Trace elements Pyrite Stibnite Substitution mechanisms Antimony mineralization Yangla Cu skarn deposit