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Site selective 5f electronic correlations inβ-uranium
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作者 邱睿智 谢刘桦 黄理 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第1期421-426,共6页
We investigate the electronic structure ofβ-uranium,which has five nonequivalent atomic sites in its unit cell,by means of the density functional theory plus Hubbard-U correction with U from linear response calculati... We investigate the electronic structure ofβ-uranium,which has five nonequivalent atomic sites in its unit cell,by means of the density functional theory plus Hubbard-U correction with U from linear response calculation.It is found that the 5f electronic correlations inβ-uranium are moderate.More interestingly,their strengths are site selective,depending on the local atomic environment of the present uranium atom.As a consequence,the occupation matrices and partial 5f density of states ofβ-uranium manifest site dependence.In addition,the complicate experimental structure ofβ-uranium could be well reproduced within this theoretical framework. 展开更多
关键词 uranium low-symmetry crystal structure 5f electronic correlation SITE-SELECTIVITY density-functional theory
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Electronic Structure and Optical Properties in Uranium Dioxide:the First Principle Calculations
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作者 隋鹏飞 戴振宏 +1 位作者 张晓玲 赵银昌 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第7期129-133,共5页
We report a study of the electronic structure and optical properties of uranium dioxide (U02) based on the ab-initio density-functional theory and using the generalized gradient approximation. To correctly describe ... We report a study of the electronic structure and optical properties of uranium dioxide (U02) based on the ab-initio density-functional theory and using the generalized gradient approximation. To correctly describe the strong correlation between 5 f electrons of a uranium atom, we employ the on-site Hubbard U correction term and optimize the correlation parameter of the bulk uranium dioxide. Then we give the structural and electronic properties of the ground state of uranium dioxide. Based on the accurate electronic structure, we calculate the complex dielectric function of UO2 and the related optieM properties, such as reflectivity, refractive index, extinction index, energy loss spectra, and absorption coefficient. 展开更多
关键词 LDA GGA electronic structure and Optical Properties in uranium Dioxide:the First Principle Calculations
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Electronic Structure Effect on Model Cluster for L1_2 Structure of Al_3Ti Intermetallic Compound with an Addition of Alloying Elements Fe, Ni and Cu
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作者 Senying LIU Rongze HU Dongliang ZHAO and Chongyu WANG(Central Iron and Steel Research Institute, Beijing, 100081, China)(To whom correspondence should be addressed)Ping LUO(National Research Cent or Certified Materials, Beijing, 100013, China)Zhongjie P 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1995年第5期369-372,共4页
By use of self-consistent field Xα scattered-wave (SCF-Xα-SW) method, the electronic structure was calculated for four models of Ti4Al14X (X=Al, Fe, Ni and Cu) clusters. The Ti4Al14X cluster was developed based on L... By use of self-consistent field Xα scattered-wave (SCF-Xα-SW) method, the electronic structure was calculated for four models of Ti4Al14X (X=Al, Fe, Ni and Cu) clusters. The Ti4Al14X cluster was developed based on L12 Al3Ti-base intermetallic compound. The results are presented using the density of states (DOS) and one-electron properties, such as relative binding tendency between the atom and the model cluster, and hybrid bonding tendency between the alloying element and the host atoms. By comparing the four models of Ti4Al14X cluster, the effect of the Fe, Ni or Cu atom on the physical properties of Al3Ti-based L12 intermetallic compounds is analyzed. The results indicate that the addition of the Fe, Ni or Cu atom intensifies the relative binding tendency between Ti atom and Ti4Al14X cluster. It was found that the Fermi level (EF) lies in a maximum in the DOS for Ti4Al14Al cluster; on the contrary, the EF comes near a minimum tn the DOS for Ti4Al14X (X=Fe, Ni and Cu) cluster. Thus the L12 crystal structure for binary Al3Ti alloy is unstable, and the addition of the Fe, Ni or Cu atom to Al3Ti is benefical to stabilize L12 crystal structure. The calculation also shows that the Fe, Ni or Cu atom strengthens the hybrid bonding tendency between the central atom and the host atoms for Ti4Al14X cluster and thereby may lead to the constriction of the lattice of Al3Ti-base intermetallic compounds. 展开更多
关键词 FE electronic structure Effect on Model Cluster for L12 structure of Al3Ti Intermetallic Compound with an Addition of Alloying elements Fe Al Ti Cu
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Study Segregation of Alloying Elements in Continuous Casting Slab with Valence Electron Structure
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作者 YahLIU ZhilinLIU +1 位作者 ChengweiZHANG YingguangZHU 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2004年第4期421-425,共5页
By calculating the electron structures of the phases that phosphor, sulfur and alloying elements dissolving inγ-Fe, the reason why alloying elements can bring centerline segregation in continuous casting slab (CCS) w... By calculating the electron structures of the phases that phosphor, sulfur and alloying elements dissolving inγ-Fe, the reason why alloying elements can bring centerline segregation in continuous casting slab (CCS) with nA, the number of electrons on the strongest covalent bonds, and the structure formation factor S were investigated, and an electron structural criterion to control and to eliminate the centerline segregation was advanced. Basing on this, the electron structures of a part of rare earth phosphides and sulfides are calculated, the physical mechanism that rare earth elements can control the segregation of phosphor and sulfur is analyzed, and the criterion is well verified. 展开更多
关键词 Valence electron structure Continuous casting slab Centerline segregation Rare-earth elements.
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The Influence of Alkaline Earth Elements on Electronic Properties ofα-Si3N4 via DFT Calculation
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作者 ZHANG Jianwen HUANG Zhifeng +3 位作者 YIN Ziqian LI Meijuan CHEN Fei SHEN Qiang 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2020年第5期863-871,共9页
We used density functional theory(DFT)calculations to study the influence of alkali earth metal element(AE)doping on the crystal structure and electronic band structure ofα-Si3N4.The diversity of atomic radii of alka... We used density functional theory(DFT)calculations to study the influence of alkali earth metal element(AE)doping on the crystal structure and electronic band structure ofα-Si3N4.The diversity of atomic radii of alkaline earth metal elements results in structural expansion when they were doped into theα-Si3N4 lattice.Formation energies of the doped structures indicate that dopants prefer to occupy the interstitial site under the nitrogen-deficient environment,while substitute Si under the nitrogen-rich environment,which provides a guide to synthesizingα-Si3N4 with different doping types by controlling nitrogen conditions.For electronic structures,energy levels of the dopants appear in the bottom of the conduction band or the top of the valence band or the forbidden band,which reduces the bandgap ofα-Si3N4. 展开更多
关键词 FIRST-PRINCIPLES density functional theory calculations alkaline earth elements dopedα-Si3N4 photoluminescence material crystal structure electronic structure
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石墨烯/钛界面合金元素偏聚与界面反应抑制机理
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作者 陈佳莹 熊小倩 +6 位作者 黄敬涛 曲囡 李明伟 程源 来忠红 刘勇 朱景川 《中国材料进展》 CAS CSCD 北大核心 2024年第3期222-229,共8页
石墨烯/Ti基复合材料因具有轻质、高比强度和优异的耐腐蚀性特性而成为极具竞争力的金属基复合材料。然而,石墨烯作为一种优秀的增强体,由于可与Ti发生剧烈的界面反应,严重阻碍了石墨烯/Ti基复合材料的发展与应用。使用第一性原理计算... 石墨烯/Ti基复合材料因具有轻质、高比强度和优异的耐腐蚀性特性而成为极具竞争力的金属基复合材料。然而,石墨烯作为一种优秀的增强体,由于可与Ti发生剧烈的界面反应,严重阻碍了石墨烯/Ti基复合材料的发展与应用。使用第一性原理计算研究合金元素对石墨烯/Ti复合材料界面行为以及电子结构的影响。选取9种合金元素(Ta,Mo,Sn,Pd,Si,Ni,Co,Mn和N)构建Ti/石墨烯/Ti界面掺杂模型,计算界面偏聚能、电子态密度、布局分析以及差分电荷密度。研究发现,当掺杂的合金元素为Ta,Mo和Sn时,界面偏聚能力较弱。同时,分析电子性质可以发现这9种合金元素均削弱了Ti原子与C原子之间的电荷转移。为新型基体钛合金设计和高性能石墨烯增强钛基复合材料设计提供了新的途径,为高性能石墨烯/Ti基复合材料的新型基体钛合金设计提供了重要参考。 展开更多
关键词 石墨烯/Ti基复合材料 合金元素 第一性原理 界面结构 电子性质
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江西路迳金伯利质煌斑岩中金云母斑晶的蚀变机制研究
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作者 席佳鑫 朱建喜 +2 位作者 杨宜坪 鲜海洋 何宏平 《矿物学报》 CAS CSCD 北大核心 2024年第5期740-751,共12页
层状硅酸盐矿物的蚀变演化过程可记录岩矿成因及地质环境变迁。三八面体云母是超基性岩中最常见的层状硅酸盐矿物,其矿物学特征已被证明能够有效地反映深部的结晶条件,但超基性岩云母的次生演化过程却尚未得到系统研究。为探明超基性岩... 层状硅酸盐矿物的蚀变演化过程可记录岩矿成因及地质环境变迁。三八面体云母是超基性岩中最常见的层状硅酸盐矿物,其矿物学特征已被证明能够有效地反映深部的结晶条件,但超基性岩云母的次生演化过程却尚未得到系统研究。为探明超基性岩中原生云母的后期演化规律及其内在机理,本研究采用微区X射线衍射、电子探针、X射线光电子能谱、聚焦离子束扫描电镜和高分辨率透射电镜等多种微区微束技术,对江西路迳金伯利质煌斑岩中的金云母及其演化产物进行了分析。结果显示,在蚀变过程中,大部分Si离子保留在金云母中,而Fe、Ti、Mn、K和Na离子则大量流入热液、次生钛铁矿和碳酸盐(而非硅酸盐产物)中。金云母的蚀变反应从缺陷位点向外扩散,首先通过溶解再结晶在缺陷处形成绿泥石、高岭石、蛇纹石等蚀变序列产物,而后通过外延生长在裂隙中充填伊利石,并在蚀变较弱的部位通过固相转变形成层间亏损金云母;蚀变产物的形成位点由相变机制控制;随着蚀变程度的降低,产物与母矿物金云母的结构相似性逐渐增加。 展开更多
关键词 金云母蚀变 层状硅酸盐 晶体结构 元素迁移 透射电镜
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复合材料夹芯结构低速冲击性能研究 被引量:1
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作者 张轶群 王治邦 +1 位作者 王长武 郑锡涛 《电子机械工程》 2024年第2期1-5,29,共6页
复合材料夹芯结构为电子设备与外层蒙皮提供了一体化设计的思路,可以大幅降低飞行器的结构重量。通过低速冲击试验和ABAQUS仿真研究了5 J和10 J冲击能量下某飞行器复合材料机翼蒙皮典型夹芯区域在低速冲击下的性能。随着冲击能量的增加... 复合材料夹芯结构为电子设备与外层蒙皮提供了一体化设计的思路,可以大幅降低飞行器的结构重量。通过低速冲击试验和ABAQUS仿真研究了5 J和10 J冲击能量下某飞行器复合材料机翼蒙皮典型夹芯区域在低速冲击下的性能。随着冲击能量的增加,复合材料泡沫夹芯结构的能量吸收率由5 J的72.0%提升至10 J的76.0%。由仿真结果可知,当冲击能量达到10 J时,出现了纤维损伤,且损伤沿表层铺层角度扩展,基体压缩损伤主要出现在冲击正面,基体拉伸损伤主要出现在冲击背面,损伤随冲击能量的增加而变大。当冲击能量达到10 J时,上面板与泡沫芯体粘接处也产生了较大的损伤。 展开更多
关键词 飞行器 电子设备 复合材料泡沫夹芯结构 低速冲击 有限元分析
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碳族单质超导性的第一性原理研究
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作者 韩沛辰 林永熠 +3 位作者 郑磊 刘其军 刘正堂 高娟 《原子与分子物理学报》 CAS 北大核心 2025年第4期87-92,共6页
同为第四主族的元素,碳、硅、锗、锡、铅具有相似的价电子排布,但超导性却并不相同.锡和铅在常压下即可实现超导,硅和锗则需要在高压下才具有超导性,而碳的常规晶体结构在常压和高压下均尚未发现其超导性.压力在很大程度上是通过改变晶... 同为第四主族的元素,碳、硅、锗、锡、铅具有相似的价电子排布,但超导性却并不相同.锡和铅在常压下即可实现超导,硅和锗则需要在高压下才具有超导性,而碳的常规晶体结构在常压和高压下均尚未发现其超导性.压力在很大程度上是通过改变晶体结构和原子之间的位置进而影响其超导性,本论文基于密度泛函理论的第一性原理计算,对碳、硅、锗、锡、铅五种第四主族元素的单质的晶体结构、电子结构、声子性质以及超导性质进行系统地对比分析.计算结果表明费米能级附近的电子态密度越高,金属体系实现超导所需的压力越小.在具有金属性的体系中价带靠近费米能级处带隙的存在会使电子更容易局域在费米能级附近,从而增大费米能级附近电子态的数目并提高体系的超导性.此研究为探究超导机制并提高材料的超导性提供思路. 展开更多
关键词 超导性 第一性原理计算 碳族元素 电子结构
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VI族元素修饰对二维AlN电子性质影响的第一性原理研究
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作者 莫秋燕 欧满琳 +2 位作者 张颂 荆涛 吴家隐 《人工晶体学报》 CAS 北大核心 2024年第9期1620-1628,共9页
采用密度泛函理论的第一性原理计算方法,研究了VI族元素(O、S、Se、Te)修饰对二维AlN电子性质的影响。计算结果表明,O修饰后,二维AlN体系的能带发生劈裂,从而转变为磁性材料;S、Se和Te修饰后,二维AlN电子态密度曲线自旋向上和自旋向下... 采用密度泛函理论的第一性原理计算方法,研究了VI族元素(O、S、Se、Te)修饰对二维AlN电子性质的影响。计算结果表明,O修饰后,二维AlN体系的能带发生劈裂,从而转变为磁性材料;S、Se和Te修饰后,二维AlN电子态密度曲线自旋向上和自旋向下完全对称,形成了非磁性结构。从态密度图可以看出,费米能级附近的态密度主要由修饰原子的p态电子和N原子的p态电子贡献,导带底部逐渐向低能区移动,导致二维AlN的吸收波长阈值从紫外线区域向可见光移动。因此,修饰的二维AlN光催化效率提高,并有应用于可见光响应的光电子和自旋电子器件的可能。 展开更多
关键词 二维AlN VI族元素 修饰 第一性原理 电子结构 磁性
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基于第一性原理的镧掺杂氧化锌的性质研究
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作者 王馨悦 许钟华 +4 位作者 吴光成 谢富焯 杨坚 祝辉亚 陈春燕 《原子与分子物理学报》 CAS 北大核心 2025年第1期163-170,共8页
本文采用第一性原理计算方法开展La掺杂ZnO的缺陷研究,分析了La在ZnO中的不同占位缺陷:替换位和间隙位缺陷的形成能、能带和态密度;证明了La掺杂ZnO的生长过程中,La替换Zn原子形成替换位缺陷的可能性要比进入间隙位形成间隙位缺陷大,而... 本文采用第一性原理计算方法开展La掺杂ZnO的缺陷研究,分析了La在ZnO中的不同占位缺陷:替换位和间隙位缺陷的形成能、能带和态密度;证明了La掺杂ZnO的生长过程中,La替换Zn原子形成替换位缺陷的可能性要比进入间隙位形成间隙位缺陷大,而在形成替换位缺陷时,选择富氧的生长环境要比富锌的生长环境好,替换位缺陷有助于提高ZnO的导电能力,改善ZnO的性能.本文的研究结果能够为La掺杂ZnO的实验和应用提供一定的理论参考. 展开更多
关键词 氧化锌 稀土元素 能带 电子态密度 第一性原理
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三维集成堆叠结构的晶圆级翘曲仿真及应用
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作者 谭琳 王谦 +2 位作者 郑凯 周亦康 蔡坚 《电子与封装》 2024年第4期1-7,共7页
随着先进电子封装产品对低成本和高性能的需求不断提高,三维集成技术以其传输速度快、功耗低、封装尺寸小、系统集成度高等优势,逐渐成为一个主流研发方向。三维集成封装通常采用晶圆级制造技术,由于半导体制造工艺及三维结构设计的复杂... 随着先进电子封装产品对低成本和高性能的需求不断提高,三维集成技术以其传输速度快、功耗低、封装尺寸小、系统集成度高等优势,逐渐成为一个主流研发方向。三维集成封装通常采用晶圆级制造技术,由于半导体制造工艺及三维结构设计的复杂性,加之晶圆尺寸增大、厚度减小等发展趋势,使得有效控制晶圆翘曲以保证产品良率和可靠性面临着更大挑战。针对12英寸晶圆的典型三维集成结构,采用有限元仿真分析方法,研究多层薄膜堆叠产生的晶圆翘曲。对临时键合、晶圆减薄、晶圆键合及解键合等不同晶圆制造工艺中的翘曲变化进行了模拟计算,并选取关键工艺及设计参数进行评估与优化。通过对比实际产品的测量结果验证了仿真模型的合理性,运用仿真方法为产品设计提供了参数选择的指导依据。 展开更多
关键词 电子封装 三维集成 晶圆级翘曲 堆叠结构 有限元仿真
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Light alloying element‐regulated noble metal catalysts for energy‐related applications 被引量:5
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作者 Hui Chen Bo Zhang +1 位作者 Xiao Liang Xiaoxin Zou 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第3期611-635,共25页
Noble metals have been widely used as heterogeneous catalysts because they exhibit high activity and selectivity for many reactions of both academic and industrial interest.The introduction of light atomic species(e.g... Noble metals have been widely used as heterogeneous catalysts because they exhibit high activity and selectivity for many reactions of both academic and industrial interest.The introduction of light atomic species(e.g.,H,B,C,and N)into noble metal lattices plays an important role in optimizing catalytic performance by modulating structural and electronic properties.In this review,we present a general overview of the recent advances in the modification of noble metals with light alloying elements for various catalytic reactions,particularly for energy‐related applications.We summarize the types,location,concentration,and ordering degree of light atoms as major factors in the performance of noble metal‐based catalysts,with emphasis on how they can be rationally controlled to promote activity and selectivity.We then summarize the synthetic strategies developed to incorporate light elements and highlight the theoretical and experimental methods for understanding the alloying effects.We further focus on the wide usage of noble metal‐based catalysts modified with different light alloying atoms and attempt to correlate the structural features with their catalytic performances.Finally,we discuss current challenges and future perspectives regarding the development of highly efficient noble metal‐based catalysts modified with light elements. 展开更多
关键词 Noble metal Heterogeneous catalysis Light element ALLOY electronic structure
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A first-principles study of B2 NiAl alloyed with rare earth elements Pr,Pm,Sm,and Eu 被引量:2
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作者 何君琦 王铀 +2 位作者 闫牧夫 潘兆义 郭立新 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第2期401-405,共5页
The structural,elastic,and electronic properties of NiAl alloyed with rare earth elements Pr,Pm,Sm,and Eu are investigated by using density functional theory(DFT).The study suggests that Pr,Pm,Sm,and Eu all tend to ... The structural,elastic,and electronic properties of NiAl alloyed with rare earth elements Pr,Pm,Sm,and Eu are investigated by using density functional theory(DFT).The study suggests that Pr,Pm,Sm,and Eu all tend to be substituted for an Al site.Ni8Al7Pm possesses the largest ductility.Only the hardness and ductility of Ni8Al7Eu are enhanced simultaneously.The covalency strength of the Ni-Al bond in Ni8Al7Pm is higher than that in Ni8Al7Eu.The covalency strength of an Al-Al bond and that of a Ni-Ni bond in Ni8Al7Eu are higher than that in Ni8Al7Pm.The Ni-Pm bond and the Ni-Eu bond are covalent,and the covalency strength of the Ni-Pm bond is greater.The Al-Pm bond and the Al-Eu bond show great covalency strength and ionicity,respectively. 展开更多
关键词 FIRST-PRINCIPLES INTERMETALLICS rare earth element electronic structure
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First-principles study of the elastic constants and optical properties of uranium metal 被引量:1
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作者 陈秋云 谭世勇 +1 位作者 赖新春 陈军 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第8期503-510,共8页
We perform first-principles calculations of the lattice constants, elastic constants, and optical properties for alpha- and gamma-uranium based on the ultra-soft pseudopotential method. Lattice constants and equilibri... We perform first-principles calculations of the lattice constants, elastic constants, and optical properties for alpha- and gamma-uranium based on the ultra-soft pseudopotential method. Lattice constants and equilibrium atomic volume are consistent pretty well with the experimental results. Some difference exists between our calculated elastic constants and the experimental data. Based on the satisfactory ground state electronic structure calculations, the optical co ductivity, dielectric function, refractive index, and extinction coefficients are also obtained. These calculated optical properties are compared with our results and other published experimental data. 展开更多
关键词 uranium electronic structure elastic constants optical properties
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The Atomic Regular Polyhedron Electronic Shell
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作者 Zilong Kong 《Journal of Modern Physics》 2013年第10期1-19,共19页
The periodic table of elements is arranged based on a series of regular polyhedron. The stability of inert gas atoms can be explained by the distribution of electrons, as well as their motion and magnetic force struct... The periodic table of elements is arranged based on a series of regular polyhedron. The stability of inert gas atoms can be explained by the distribution of electrons, as well as their motion and magnetic force structure. A magnetic force regular octahedron is proposed. It is a unique configuration that best satisfies the convergence of electrons moving in the same direction within regular polyhedra. In the case of an electrostatic force crust, the formal electron spin accounts for the crusts intrinsic magnetic moment exceeding the speed of light. If one is to consider that the electron has a magnetic outer layer and an electrostatic inner layer, then the question can be solved and abovementioned inference can provide the basis for magnetic force and momentum for the regular octahedron model. The electron periphery has twenty-petal adsorptive substances;the existence of adsorptive substance causes the magnetic force greater than the electrostatic force. Each electronic shell in the regular polyhedron is in accordance with the electron configuration of periodic table of elements;the kinetic track of each electron is a surface of regular polyhedron. The magnetic properties of iron, cobalt, and nickel can be explained by the regular dodecahedron electronic shell of an atom. The electron orbit converged from reverse direction can explain diamond. The adsorptive substances found in atomic nuclei and electrons are defined as magnetic particles called magnetons. The thermodynamic magneton theory can be better explained when it is analyzed using principles of thermodynamics, superconductivity, viscosity, and even in the creation of glass. The structure of the light is a helical line. 展开更多
关键词 ATOMIC structure REGULAR POLYHEDRON electronic SHELL Periodic TABLE of elements Light Diamond
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Influence on electron energy loss spectroscopy of the niobium-substituted uranium atom:A density functional theory study
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作者 LU Chunhai NI Shijun +2 位作者 CHEN Wenkai ZHANG Chengjiang WANG Yongli 《Nuclear Science and Techniques》 SCIE CAS CSCD 2008年第6期365-369,共5页
We present the electronic structure and electron energy loss spectroscopy (EELS) for uranium, niobium and U3Nb in which uranium is substituted by niobium. Comparing the electronic structures and optical properties for... We present the electronic structure and electron energy loss spectroscopy (EELS) for uranium, niobium and U3Nb in which uranium is substituted by niobium. Comparing the electronic structures and optical properties for uranium, niobium and U3Nb, we found that when niobium atom replaces uranium atom in the center lattice, density of state (DOS) of U3Nb shifts downward to low energy. Niobium affects DOS for f and d electrons more than that for p and s electrons. U3Nb is similar to uranium for the electronic energy loss spectra. 展开更多
关键词 电子能损耗光谱 电子构造 局部密度近似值
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铀、钪族金属氮化碳配合物结构、成键和还原性质的密度泛函理论研究
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作者 安然 孔明 +5 位作者 胡万权 倪义东 沈永鹏 李淑君 郭元茹 潘清江 《核化学与放射化学》 CAS CSCD 北大核心 2023年第5期436-443,共8页
石墨相氮化碳负载金属可制备高催化性能的单原子催化剂。本工作采用全电子相对论密度泛函理论研究了g-C_(3)N_(4)(CN)结构单元配位和稳定金属的行为;探索了形成配合物[M(CN)]^(z+)(M=Sc、Y、La、Ac和U;z=2和3)的结构、配体-金属相互作... 石墨相氮化碳负载金属可制备高催化性能的单原子催化剂。本工作采用全电子相对论密度泛函理论研究了g-C_(3)N_(4)(CN)结构单元配位和稳定金属的行为;探索了形成配合物[M(CN)]^(z+)(M=Sc、Y、La、Ac和U;z=2和3)的结构、配体-金属相互作用和单电子还原性质。计算发现,配体通过六条M-N配位键配位中心离子,每条键强度为-0.79~-0.47 eV。对于Sc配合物,单电子还原主要发生在金属中心,而La和U配合物则是金属修饰的配体还原机制;Y配合物的配体和金属被均匀地还原;相比而言,Ac配合物的还原电子完全被配体捕获,金属几乎未参与。电子结构研究表明,[U(CN)]^(3+)具有3个U(5f)单电子高占据轨道,表明中心U为三价氧化态;而[U(CN)]^(2+)虽然具有4个U(5f)单电子占据轨道,但是配体的贡献是不可忽略的,即其U中心的氧化态介于二三价之间。 展开更多
关键词 g-C_(3)N_(4) 铀、钪族金属 成键作用 电子结构 密度泛函理论计算
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采用第一性原理计算U3Si2核燃料的进展综述
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作者 王坤 乔英杰 +3 位作者 都时禹 王晓东 张一鸣 张晓红 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2023年第6期1060-1071,共12页
U_(3)Si_(2)核燃料因其具有较高的热导率以及良好的综合性能,已被预测为核反应堆先进燃料,是事故容错核燃料的候选材料。近年的研究结果表明,U_(3)Si_(2)较U3Si表现出更好的非晶化行为,具有更高研究价值。然而,有关U_(3)Si_(2)在第一性... U_(3)Si_(2)核燃料因其具有较高的热导率以及良好的综合性能,已被预测为核反应堆先进燃料,是事故容错核燃料的候选材料。近年的研究结果表明,U_(3)Si_(2)较U3Si表现出更好的非晶化行为,具有更高研究价值。然而,有关U_(3)Si_(2)在第一性原理计算方面工作的系统性综述较少。因此,本文通过总结近几年U-Si核燃料的理论计算工作,重点综述了U_(3)Si_(2)的晶体结构、电子结构、力学性质、抗氧化性质以及裂变产物行为在第一性原理计算方面的研究进展。可以发现,与其他核燃料相比,采用第一性原理计算U_(3)Si_(2)核燃料相对滞后且相关的物理化学数据短缺。本文可为进一步开发耐事故U_(3)Si_(2)核燃料提供重要参考。 展开更多
关键词 耐事故燃料 U-Si核燃料 非晶化行为 第一性原理 电子结构 力学性质 氧化行为 裂变产物行为
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C,Fe,Si掺杂Al_(3)V合金的电子结构与力学性能 被引量:2
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作者 唐树伟 吴孟修 +2 位作者 罗东明 王鑫林 白树林 《中国有色金属学报》 EI CAS CSCD 北大核心 2023年第1期138-148,共11页
采用第一性原理计算方法研究了铝钒合金Al_(3)V及其C、Fe、Si取代掺杂的Al_(24)V_(7)X、Al_(23)V_(8)X (X=C,Fe,Si)合金晶体结构的稳定性、电子结构和力学性能。计算结果表明,X (X=C,Fe,Si)掺杂对Al_(3)V合金晶体结构的影响较小,Al_(24)... 采用第一性原理计算方法研究了铝钒合金Al_(3)V及其C、Fe、Si取代掺杂的Al_(24)V_(7)X、Al_(23)V_(8)X (X=C,Fe,Si)合金晶体结构的稳定性、电子结构和力学性能。计算结果表明,X (X=C,Fe,Si)掺杂对Al_(3)V合金晶体结构的影响较小,Al_(24)V_(7)X和Al_(23)V_(8)X (X=C,Fe,Si)仍然保持明显的Al_(3)V金属特征。Mulliken电荷布居和重叠布居分析显示X (X=C,Fe,Si)会与周围Al和V原子产生键合作用,提高Al_(24)V_(7)X和Al_(23)V_(8)X (X=C,Fe,Si)的稳定性和抗变形能力。X (X=C,Fe,Si)的取代掺杂对Al_(3)V合金晶体的刚度影响较小,但能使Al_(3)V合金材料的塑性有所提升,有望能有效解决Al_(3)V合金的脆性问题,拓宽Al_(3)V合金的应用范围。 展开更多
关键词 Al_(3)V合金 第一性原理计算 力学性能 电子结构 元素掺杂
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