检索结果-南通市图书馆

Design and optimization of the composition and mechanical properties for non-equiatomic CoCrNi medium-entropy alloys

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

journal of Materials Science & Technology 2023年第8期139卷 232-244页

作者： j.X.Yan Z.j.Zhang p.Zhang j.H.Liu H.yu Q.M.Hu j.B.Yang Z.F.Zhang Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering Chongqing Jiaotong UniversityChongqing 400074China chool of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China School of Information Science and Engineering Shenyang University of TechnologyShenyang 111003China

The development of multi-principal element alloys(MpEAs,also called as high-or medium-entropy al-loys,HEAs/MEAs)provides tremendous possibilities for materials ***,designing MpEAs with desirable mechanical properties confronts great challenges due to their vast composition *** this work,we provide an essential criterion to efficiently screen the CoCrNi MEAs with outstanding strength-ductility *** negative Gibbs free energy difference△E_(FCC-BCC)between the face-centered cubic(FCC)and body-centered cubic(BCC)phases,the enhancement of shear modulus G and the decline of stacking fault energy(SFE)γ_(isf)are combined as three requisites to improve the FCC phase stability,yield strength,deformation mechanisms,work-hardening ability and ductility in the *** effects of chemical composition on△E_(FCC-BCC),G andγisf were investigated with the first principles calculations for Co_(x)Cr_(33)Ni_(67-x),Co_(33)Cr_(y)Ni_(67-y)and Co_(z)Cr_(66-z)Ni_(34)(0≤x,y≤67 and 0≤z≤66)*** on the essential criterion and the calculation results,the composition space that displays the neg-ative Gibbs free energy difference△E_(FCC-BCC),highest shear modulus G and lowest SFEγ_(isf)was screened with the target on the combination of high strength and excellent *** this context,the optimal composition space of Co-Cr-Ni alloys was predicted as 60 at.%-67 at.%Co,30 at.%-35 at.%Cr and 0 at.%-6 at.%Ni,which coincides well with the previous experimental evidence for Co_(55)Cr_(40)Ni_(5)*** valid-ity of essential criterion is further proved after systematic comparison with numerous experimental data,which demonstrates that the essential criterion can provide significant guidance for the quick exploitation of strong and ductile MEAs and promote the development and application of MpEAs.

关键词： Medium-entropy alloys First-principles calculations phase stability Stacking-fault energy Strength Ductility

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

星形AB共聚物和A均聚物的共组装模拟研究

原子与分子物理学报 2025年第5期42卷 90-94页

作者：段润宇新疆大学物理科学与技术学院乌鲁木齐830017

具有独特结构的纳米粒子在高分子材料领域具有广泛的应用.本文采用耗散粒子动力学模型系统的研究了三臂星形AB二嵌段共聚物和A均聚物共混体系的共组装相行为.通过调节聚集体中星形共聚物浓度和AB嵌段的长度比有效地控制了AB/A共混体系... 详细信息

具有独特结构的纳米粒子在高分子材料领域具有广泛的应用.本文采用耗散粒子动力学模型系统的研究了三臂星形AB二嵌段共聚物和A均聚物共混体系的共组装相行为.通过调节聚集体中星形共聚物浓度和AB嵌段的长度比有效地控制了AB/A共混体系中聚集体的共组装形貌.预测了一些有趣的结构,比如,具有较厚壳层的核-壳-补丁结构、具有壳层的且中心凹陷的圆盘状结构以及不规则椭球的多室结构.本文还发现对于具有较长A嵌段的星形链,增大A均聚物在聚集体中的浓度能够消除聚集体内B嵌段形成的核;对于具有较短A嵌段的星形链,少量的A均聚物能够诱导聚集体共组装成具有长条状核的多室纳米粒子.

关键词：耗散粒子动力学星形二嵌段共聚物共组装纳米粒子

Current-induced synchronized magnetization reversal of two-body Stoner particles with dipolar interaction

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Chinese physics B 2018年第6期27卷 434-442页

作者： Zhou-Zhou Sun yu Yang j Schliemann College of physics Optoelectronics and Energy Soochow University Suzhou 215006 China Institute for Theoretical physics University of Regensburg D-93040 Regensburg Germany

We investigate magnetization reversal of two-body uniaxial Stoner particles, by injecting spin-polarized current through a spin-valve structure. The two-body Stoner particles perform synchronized dynamics and can act as an information bit in computer technology. In the presence of magnetic dipole–dipole interaction（DDI） between the two particles,the critical switching current Ic for reversing the two dipoles is analytically obtained and numerically verified in two typical geometric configurations. The Ic bifurcates at a critical DDI strength, where Ic can decrease to about 70% of the usual value without DDI. Moreover, we also numerically investigate the magnetic hysteresis loop, magnetization self-precession,reversal time and synchronization stability phase diagram for the two-body system in the synchronized dynamics regime.

关键词： magnetization reversal spin-polarized current Stoner particle

Applications of genetic code expansion technology in eukaryotes

在线全文

学校读者我要写书评

暂无评论

protein & Cell 2024年第5期15卷 331-363页

作者： Qiao-ru Guo yu j.Cao State Key Laboratory of Chemical Oncogenomic Guangdong Provincial Key Laboratory of Chemical GenomicsPeking University Shenzhen Graduate SchoolShenzhen 518055China Institute of Chemical Biology Shenzhen Bay LaboratoryShenzhen 518132China

Unnatural amino acids(UAAs)have gained significant attention in protein engineering and drug development owing to their ability to introduce new chemical functionalities to *** eukaryotes,genetic code expansion(GCE)enables the incorporation of UAAs and facilitates posttranscriptional modification(pTM),which is not feasible in prokaryotic *** is also a powerful tool for cell or animal imaging,the monitoring of protein interactions in target cells,drug development,and switch ***,there is keen interest in utilizing GCE in eukaryotic *** review provides an overview of the application of GCE in eukaryotic systems and discusses current challenges that need to be addressed.

关键词： genetic code expansion unnatural amino acid eukaryotes basic research therapeutic applications

A two-scale method for identifying mechanical parameters of composite materials with periodic configuration

在线全文

学校读者我要写书评

暂无评论

Acta Mechanica Sinica 2006年第6期22卷 581-594页

作者： j.Z. Cui X.G. yu Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing 10080 China

In this paper, a two-scale method （TSM） is presented for identifying the mechanics parameters such as stiffness and strength of composite materials with small periodic configuration. Firstly, a formulation is briefly given for two-scale analysis （TSA） of the composite materials. And then a two-scale computation formulation of strains and stresses is developed by displacement solution with orthotropic material coefficients for three kinds of such composites structures, i.e., the tension column with a square cross section, the bending cantilever with a rectangular cross section and the torsion column with a circle cross section. The strength formulas for the three kinds of structures are derived and the TSM procedure is discussed. Finally the numerical results of stiffness and strength are presented and compared with experimental data. It shows that the TSM method in this paper is feasible and valid for predicting both the stiffness and the strength of the composite materials with periodic configuration.

关键词： Two-scale method Stiffness Strength Composite materials Small periodic configuration

在线全文

学校读者我要写书评

暂无评论

思想政治教育数字化的价值意蕴及实践进路

新疆师范大学学报（哲学社会科学版） 2025年第2期46卷 128-136页

作者：于祥成刘成合肥工业大学安徽合肥230009 武汉大学马克思主义学院湖北武汉430064

随着数字技术的广泛应用和教育数字化转型发展,数字化变革成为思想政治教育创新发展的必然选择。面对新的时代境遇,要全面把握思想政治教育数字化的内涵和特征,深刻认识思想政治教育数字化在推动思想政治教育认知重建、资源重组、话语... 详细信息

随着数字技术的广泛应用和教育数字化转型发展,数字化变革成为思想政治教育创新发展的必然选择。面对新的时代境遇,要全面把握思想政治教育数字化的内涵和特征,深刻认识思想政治教育数字化在推动思想政治教育认知重建、资源重组、话语重构、形态重塑等方面的重要价值。同时,要秉承数字理念,构建思想政治教育数字范式;搭建数字平台,优化思想政治教育数字服务;培育数字素养,提升思想政治教育数字技能;厚植“数字土壤”,形塑思想政治教育数字生态,积极探索思想政治教育数字化实践创新路径。

关键词：思想政治教育数字化数字技术实践进路

Four New Steroidal Alkaloids from the Roots of Sarcococca Vagans

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 1997年第6期8卷 511-514页

作者： yu, SS Zou, ZM Zen, j yu, DQ Cong, pZ CHINESE ACAD MED SCI INST MAT MEDBEIJING 100050PEOPLES R CHINA

Four new steroidal alkaloids, named sarcovagine A-D, were isolated from the roots of Sarcococca vagans. Their structures were determined as 20 alpha-dimethylamino-2 beta,4 beta-dihydroxy-3 beta-tigloylamino-5 alpha-pregnane (sarcovagine A, 1), 20 alpha-dimethylamino-2 alpha-hydroxy-4 beta-acetoxy-3 beta-tigloylamino-5 alpha-pregnane (sarcovagine B, 2), 20 alpha-dimethylamino-4 beta-acetoxy-3 beta-tigloylamino-5 alpha-pregnane (sarcovagine C, 3), 20 alpha-dimethylamino-3-tigloylamino-5 alpha-pregn-2(3)-en-4-one (sarcovagine D, 4), respectively.

关键词： Four New Steroidal Alkaloids from the Roots of Sarcococca Vagans HNMR data NH EIMS ppm

单层Cs_(2)pbI_(2)Cl_(2)中点缺陷的形成与稳定性

在线全文

学校读者我要写书评

暂无评论

原子与分子物理学报 2025年第5期42卷 130-136页

作者：何诗颖赵宇清邹代峰许英廖雨洁禹卓良湖南科技大学物理与电子科学学院湘潭411201 智能传感器与新型传感器材料湖南省重点实验室湘潭411201 湖南理工学院物理与电子科学学院岳阳414006

Cs_(2)pbI_(2)Cl_(2)是卤化铅钙钛矿材料的新成员,由于其高的光吸收系数和长的载流子迁移距离等优异的光电物理性能,在太阳能电池、光电探测器、场效应晶体管以及发光二极管等领域受到广泛的关注.其中光电材料及器件的优良特性由电子结... 详细信息

Cs_(2)pbI_(2)Cl_(2)是卤化铅钙钛矿材料的新成员,由于其高的光吸收系数和长的载流子迁移距离等优异的光电物理性能,在太阳能电池、光电探测器、场效应晶体管以及发光二极管等领域受到广泛的关注.其中光电材料及器件的优良特性由电子结构决定,而钙钛矿的点缺陷对电子结构具有重要的调控,且单层Cs_(2)pbI_(2)Cl_(2)中点缺陷的研究尚且缺乏.本文基于密度泛函理论的第一性原理计算,对单层Cs_(2)pbI_(2)Cl_(2)的铯空位、碘空位、氯空位、铯替代铅、碘替代铯、碘替代铅、碘替代氯、氯替代铯、氯替代铅和氯替代碘的缺陷形成能和稳定性进行了研究.结果表明:在富铅和缺铅条件下,碘替代氯和氯替代碘的缺陷形成能偏低,且氯替代碘能有效降低体系总能,提高体系稳定性.在缺铅条件下铯空位缺陷形成能低于富铅条件,在缺铅条件下更易形成铯空位;富铅和缺铅条件下对碘替代氯和氯替代碘的缺陷形成能基本无影响.上述研究结果有助于理解点缺陷对钙钛矿材料稳定性的影响,同时也为未来实验上设计基于Cs_(2)pbI_(2)Cl_(2)的高效的光电子器件提供理论依据.

关键词：单层Cs_(2)pbI_(2)Cl_(2) 形成能点缺陷稳定性

维普期刊数据库博看期刊

在线全文

学校读者我要写书评

暂无评论

体相二硫化铼中点缺陷的形成与稳定性

原子与分子物理学报 2025年第5期42卷 143-150页

二硫化铼是过渡金属二硫族化合物的成员,由于层间的范德华作用、合适的带隙、高的光吸收系数和长的载流子迁移距离在光电子研究领域引起广泛的关注.其中光电材料及器件的优良特性由电子结构决定,而半导体的缺陷能级对电子结构具有重要... 详细信息

二硫化铼是过渡金属二硫族化合物的成员,由于层间的范德华作用、合适的带隙、高的光吸收系数和长的载流子迁移距离在光电子研究领域引起广泛的关注.其中光电材料及器件的优良特性由电子结构决定,而半导体的缺陷能级对电子结构具有重要的调控,且体相二硫化铼的缺陷研究尚且缺乏.本文基于密度泛函理论的第一性原理计算,对体相二硫化铼的铼空位、硫空位、钨掺杂(或替代)铼、钨掺杂硫、锝掺杂铼和锝掺杂硫的缺陷形成能和稳定性进行了研究.结果表明:钨掺杂硫和锝掺杂硫形成深施主能级缺陷,铼空位形成浅施主能级缺陷.在富铼和富硫条件下,钨掺杂铼的缺陷形成能低且能有效降低体系总能,提高体系稳定性.钨掺杂硫的缺陷虽然能降低体系的总能提高二硫化铼的稳定性,但较大的缺陷形成能表明钨掺杂硫缺陷难以形成.上述研究结果有助于理解缺陷能级对半导体深浅能级和稳定性的影响,同时也为未来实验上设计基于二硫化铼的高效的光电子器件提供理论依据.

关键词：体相二硫化铼形成能缺陷能级稳定性