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5052铝合金成形极限预测及数值模拟

塑性工程学报 2024年第6期31卷 43-49页

作者：孙旭慧薛凤梅沈文锦李陈真李宇涛太原理工大学材料科学与工程学院山西太原030024

基于Nakazima半球凸模胀形实验,利用有限元软件建立其简化模型。分析了润滑条件、冲压速度和凹模圆角半径对5052铝合金成形极限的影响。结果显示:随着摩擦因数的增大,成形极限曲线(FLC)向下偏移,表明理想的润滑条件有利于板材在复杂工... 详细信息

基于Nakazima半球凸模胀形实验,利用有限元软件建立其简化模型。分析了润滑条件、冲压速度和凹模圆角半径对5052铝合金成形极限的影响。结果显示:随着摩擦因数的增大,成形极限曲线(FLC)向下偏移,表明理想的润滑条件有利于板材在复杂工艺下的成形;增大冲压速度也使FLC呈现下降的趋势,即在不考虑实际生产效率的情况下,降低冲压速度可以改善材料的延展性;而增大凹模圆角半径使FLC向上偏移,提高了板料的成形极限。将模拟结果与实验结果对比,两者较高的吻合度验证了有限元预测的可靠性。

关键词： 5052铝合金成形极限图 Nakazima实验数值模拟

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Abstracts

文史哲 2014年第1期 165-168页

作者： Yang Yi li zhen chen Lai

The Root of Formal Beauty： How to Answer Marx＇s ＂Three Questions on Formal Beauty＂ Zhao Jinghuan In 1857, Marx wrote the entry of ＂aesthetics＂ for The New Encyclopedia Americana upon invitation. Due to the lack of material on philosophy, psychology, and history of arts at that timed Marx raised the ＂three ques- tions on formal beauty. ＂ Afterwards, much debate in academic circles ensued. This paper attempts to provide an answer to these questions. About the first question, the philosophical basis of formal beauty, I think that the golden rule is the visible dialectics.

关键词：《文史哲》英文摘要期刊编辑工作

NIR-IIb-triggered photodynamic therapy combined with chemotherapy platform based on rare-earth-doped nanoparticles

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Rare Metals 2024年第7期43卷 3220-3231页

作者： Zhuo Tu Yong Wan Juan Ge chen-chen li Tao liang zhen li Chemistry and Chemical Engineering Hubei UniversityWuhan 430062China

Photodynamic therapy(PDT),with high spatiotemporal selectivity,minimal side effects and less drug resistance,has emerged as a promising approach for the treatment of ***,inadequate penetration depth and poor efficacy seriously restrict its practical *** address these challenges,we developed a combined therapy platform(RENP@C/D-FA)based on rare-earth-doped nanoparticles(RENPs)with a structure of NaErF_(4):Tm(0.5%)@NaYF_(4),on which photosensitizer Ce6(chlorin e6)and chemo-therapeutic drug(DOX)(doxorubicin)were loaded by encapsulating with an amphiphilic polymer distearoyl phosphatidylethanolamine-polyethylene glycol-folic acid(DSPE-PEG-FA).RENPs with NaErF_(4) as the matrix possess multiple excitation/emission peaks,enabling activation of PDT under near-infrared-Ⅱb(NIR-Ⅱb,1500-1700 nm)excitation and luminescence imaging in NIR-Ⅱb region by absorbing 808 nm near-infrared ***,DOX can be selectively released in the acidic microenvironment of *** from the tumor targeting capability of folic acid,this platform can successfully ablate tumor cells and inhibit tumor growth by combining PDT and *** innovative approach holds great promise as a powerful tool for cancer treatment,showing the potential to revolutionize PDT.

关键词： Photodynamic therapy Rare-earth-doped nanoparticles NIR-IIb Chemotherapy Combined therapy

Solubility measurement,correlation and thermodynamic properties of 2,3,4-trichloro-1,5-dinitrobenzene in fifteen mono-solvents at temperatures from 278.15 to 323.15 K

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Chinese Journal of Chemical Engineering 2023年第6期58卷 224-233页

作者： Yun-Zhang liu Lu-Yao Zhang Dan He li-zhen chen Zi-Shuai Xu Jian-Long Wang School of Chemical Engineering and Technology North University of ChinaTaiyuan 030051China Gansu Yinguang Chemical Industry Group Co.Ltd Baiyin 730900China

The solubility of 2,3,4-trichloro-1,5-dinitrobenzene(TCDNB) was measured by a laser dynamic method over the temperature range from 278.15 K to 323.15 K under 0.1 MPa in fifteen mono-solvents(methanol,ethanol,isopropanol,n-butanol,toluene,dichloromethane,chloroform,tetrachloromethane,1,2-dichloroethane,acetone,ethyl acetate,acetonitrile,N-methylpyrrolidone(NMP),N,Ndimethylformamide dimethyl sulfoxide(DMF),dimethyl sulfoxide(DMSO).The solubility of TCDNB could be increased with increasing temperature in fifteen *** solubility is in the following order at 298.15 K:NMP>DMF>DMSO>toluene>acetone>ethyl acetate>dichloromethane>1,2-dich loroethane>chloroform>acetonitrile>tetrachloromethane>methanol>ethanol>n-butanol>*** KAT-LSER model was used to investigate the solvent effect,which revealed that the hydrogen bond acidity of solvents has a greater effect on TCDNB *** van't Hoff model,the modified Apelblat model,theλh model,and the non-random two liquid(NRTL)model were used to correlate the solubility of *** calculated solubility data agreed well with the experimental data,and the modified Apelblat model fit ***,the van't Hoff and Gibbs equations were also used to calculate the dissolution thermodynamic properties of TCDNB in various *** dissolution could be an enthalpy-driven,non-spontaneous,and endothermic process in fifteen *** determination and fitting solubility of TCDNB,as well as the calculation of its thermodynamic properties,would be critical in the purification and crystallization of its preparation process research.

关键词： 2,3,4-Trichloro-1 5-dinitrobenzene(TCDNB) Solid-liquid equilibrium Laser dynamic method Solubility model Thermodynamics properties

Influence of Current Density on the Photocatalytic Activity of Nd:TiO_(2) Coatings

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 32-38页

作者：施渊吉 ZHANG zhen DAI Yunzhong li Jingxiao chen Zeyu School of Mechanical Engineering Nanjing Vocational University of Industry TechnologyNanjing 210046China College of Material Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016China School of Materials Science and Engineering Nanjing Institute of TechnologyNanjing 211167China Key Laboratory of Modern Agricultural Equipment and Technology Jiangsu UniversityZhenjiang 212013China

The Nd:TiO_(2 )PEO coatings were formed in a phosphate-based electrolyte with the addition of Nd_(2)O_(3 )under the current density of 150,200,250 and 300 m A/cm^(2).SEM results showed that the micropores decreased on quantity and increased on scale with the increasing current *** results revealed that the roughness of the coatings increased with the increasing current *** and composition analysis showed that the Nd:TiO_(2) coatings were mainly composed of anatase and rutile *** the anatase phase content has reached the maximum value at the current density of 250 m A/cm^(2).XPS results indicated that Ti2p spin-orbit components of the Nd:TiO_(2) coatings are shifted towards higher binding energy,compared with the pure TiO_(2) coating,suggesting that some of the Nd^(3+)ions are combined with TiO_(2) lattice and led to *** test showed that the photocatalytic activity of Nd:TiO_(2) coatings varied in the same pattern with the anatase content variation in Nd:TiO_(2) *** photocatalytic experiment results show that the photocatalytic activity of Nd:TiO_(2) coatings can be greatly enhanced with moderate amount of Nd^(3+).However,excessive amount of Nd^(3+)does not have an effective impact on the photoctalytic activity improvement.

关键词： PEO current density AFM XPS Nd:TiO_(2) photocatalytic

Asymmetric alkenylation reaction of benzoxazinones with diarylethylenes catalyzed by B(C_(6)F_(5))_(3)/chiral phosphoric acid

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Chinese Chemical Letters 2024年第5期35卷 135-140页

作者： zhen liu Zhi-Yuan Ren chen Yang Xiangyi Shao li chen Xin li State Key Laboratory of Elemento-Organic Chemistry Frontiers Science Center for New Organic MatterCollege of ChemistryNankai UniversityTianjin 300071China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China zhenhai High School of Zhejiang Ningbo 315299China

Catalytic enantioselective alkenylation is an efficient method to construct chiral alkene molecules,but the asymmetric alkenylation of simple alkenes catalyzed by metal-free catalysts remains an elusive ***,we reported an asymmetric alkenylation of benzoxazinones with diarylethylenes by utilizing a B(C_(6)F_(5))_(3)/chiral phosphoric acid catalyst.A broad of benzoxazinones and diarylethylenes with electron-withdrawing and electron-donating groups were tolerated(up to 95%yield and 97.5:2.5 e.r.)in the methodology under mild reaction ***,the synthetic utility was confirmed by the scaled-up reaction and transformations of the *** mechanism was preliminarily explored by control reactions,nonlinear effect experiment and DFT calculations.

关键词： Asymmetric alkenylation Simple alkenes Benzoxazinones B(C_(6)F_(5))_(3)/chiral phosphoric acid Theoretical calculations

Small RNA existed in commercial reverse transcriptase： primary evidence of functional small RNAs

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Protein & Cell 2015年第1期6卷 1-5页

作者： Jie Xu Xi chen Donghai li Qun chen zhen Zhou Dongxia Hou Jin Wang Qipeng Zhang Ke Zen chen-Yu Zhang Jiangsu Engineering Research Center for microRNA Biology and Biotechnology State Key Laboratory of Pharmaceutical Biotechnology School of Life Sciences Nanjing University Nanjing 210093 China

SMALL RNA IN REVERSE TRANSCRIPTASE： TOO SMALL TO BE FOUND Significant background in no-template or no-primer RT-PCR is frequently noted. However, the underlying mechanism is still unclear. In this issue, Jie Xu and colleagues reveal that the com- mercial reverse transcriptases contain small RNAs. In AMV reverse transcriptase, they detected microRNAs derived from the virus host chick or other birds. This surprising finding at least partially explains the high background in some AMV reverse transcriptases based RT-PCR.

关键词： Reverse Transcriptase Small RNAs miRNA Profile miRNA Expression Profile Solexa Sequencing

Precise immobilization of metal single atoms into a porphyrinic metal-organic framework for an efficient alkene hydrosilylation

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Nano Research 2024年第7期17卷 5914-5921页

作者： Chun-Ying chen Qi-Jie Mo Fu-zhen li Hai-li Song li Zhang MOE Laboratory of Bioinorganic and Synthetic Chemistry Lehn Institute of Functional MaterialsSchool of ChemistrySun Yat-Sen UniversityGuangzhou 510006China

Alkene hydrosilylation is one of the most concise and atom-economical methods to synthesize organosilicon ***,we reported the precise immobilization of metal single atoms(M-SAs;M=Ru,Rh,Ir,Pd,Pt,and Au)into a porphyrinic metalorganic framework(MOF)of PCN-222(PCN=porous coordination network),and then applied the resultant MOF composites of M-SAs@PCN-222 to alkene *** solvent-free conditions,Pt-SAs@PCN-222 displayed an especially high catalytic efficiency with the turnover frequency up to 119 s−1 and the maximum turnover number of 906,250 at room *** and theoretical studies revealed that there existed strong interactions between Pt-SAs@PCN-222 and the substrates,which helped to condense the substrates in the cavities of the porous *** density functional theory calculations and molecular dynamics simulations disclosed that PCN-222 could transfer electrons to Pt-SAs to enhance the silane oxidative addition and drive the reaction to proceed smoothly via Chalk–Harrod pathway.

关键词： alkene hydrosilylation single atom catalysts metal-organic frameworks precision chemistry synergistic catalysis

Neuroimaging brain growth charts:A road to mental health

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Psychoradiology 2021年第4期1卷 272-286页

作者： li-zhen chen Avram JHolmes Xi-Nian Zuo Qi Dong State Key Laboratory of Cognitive Neuroscience and Learning Beijing Normal UniversityBeijing 100875China Department of Psychology Yale UniversityNew HavenCT 06511USA Department of Psychiatry Yale UniversityNew HavenCT 06511USA National Basic Science Data Center Beijing 100190China Developmental Population Neuroscience Research Center International Data Group/McGovern Institute for Brain ResearchBeijing Normal UniversityBeijing 100875China Research Center for lifespan Development of Mind and Brain Institute of PsychologyChinese Academy of SciencesBeijing 100101China

Mental disorders are common health concerns and contribute to a heavy global burden on our modern *** is challenging to identify and treat them *** evidence suggests the incidence of various psychiatric and behavioral disorders is closely related to the atypical development of brain structure and *** identification and understanding of atypical brain development provide chances for clinicians to detect mental disorders earlier,perhaps even prior to onset,and treat them more *** invaluable and necessary method in identifying and monitoring atypical brain development are growth charts of typically developing individuals in the *** brain growth charts can offer a series of standard references on typical neurodevelopment,representing an important resource for the scientific and medical *** the present paper,we review the relationship between mental disorders and atypical brain development from a perspective of normative brain development by surveying the recent progress in the development of brain growth charts,including four aspects on growth chart utility:1)cohorts,2)measures,3)mechanisms,and 4)clinical *** doing so,we seek to clarify the challenges and opportunities in charting brain growth,and to promote the application of brain growth charts in clinical practice.

关键词： growth chart development neuroimaging reliability mental health