检索结果-南通市图书馆

Nucleation and growth of L1_(2)-Al_(3)RE particles in aluminum alloys:A first-principles study

Journal of Rare Earths 2023年第7期41卷 1116-1126,I0005页

作者： Touwen Fan Zixiong Ruan Feng Zhong Chaoyang Xie Xiaofeng Li Dongchu Chen Pingying Tang Yuanzhi Wu College of Science Hunan Institute of TechnologyHengyang 421002China Research Institute of Automobile Parts Technology Hunan Institute of TechnologyHengyang 421002China School of Materials Science and Engineering North University of Chin1Taiyuan 030051China School of Material Science and Hydrogen Energy Engineering Foshan UniversityFoshan 528001China Key Laboratory of New Electric Functional Materials of Guangxi Colleges and Universities Nanning Normal UniversityNanning 530023China

The internal mechanisms of nucleation and growth of L1_(2)-AI_(3)RE(RE=Sc,Y,La-Lu) second phases in Al alloys were investigated by combining first-principles calculations with quasi-harmonic approximation(QHA).The calculated results show that the diffusion rate D_s and chemical potential AG_V increase with the increase of *** the increase of atomic number,the D_s and the strain energy ΔE_(CS)increase firstly from Sc to La,and then decreases,while the calculated interface energy γ_(α/β) and ΔG_V show opposite *** on above calculated results,the critical nucleation radius R*and coarsening rate K_(LSW) are obtained from the classical nucleation theory(CNT) and LSW model of the Ostwald ripening of particles,*** the increase of atomic number,the R*increases firstly,and then decreases for all planes at finite *** the K_(LSW) shows opposite variation to the R^(*).From this point of view,it is reasonably speculated that Y and later RE elements can replace the expensive Sc for heat-resistance Al *** solubility c_(∞) of particles is usually very small at low temperature,and there is obvious solubility only when the temperature reaches 600 *** surface energies E_(sur) of AI_(3)RE compounds and Al solid solution are respectively larger and smaller than that of pure Al,respectively,except for the surface(001) and(110) of Al_(3)*** all planes,with the increase of atomic number of RE,E_(sur) decreases firstly from Sc to La,and then increases linearly to *** results are helpful for designing high performance heat-resistance Al alloys.

关键词： First-principles calculations diffusion rate Quasi-harmonic approximation Particle nucleation and growth Rare earths

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Kinetic Factors for Intensive Reaction of Magnesium-Based Spheroidiser in Hot Metal

引用

Journal of Iron and Steel Research International 2005年第1期12卷 9-11页

作者： SHENG Da Tsinghua University

The spheroidiser is a necessary additive to manufacture ductile *** with the same hot metal,spheroidisers and treated technology,reactions differ greatly from each *** reaction may be quite normal in one case,but very intensive for another *** effects of kinetic factors such as size,surface area and morphology o f spheroidiser on the reaction of spheoidization are studied.

关键词： hot metal kinetic factor diffusion rate intensive reaction spheroidiser magnesium

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Permanence and Existence of Positive Periodic Solution for Diffusive Lotka-Volterra Model

引用

生物数学学报 1997年第1期12卷 8-14页

作者： Yang Xia Chen Jufang(Xinjiang Shihezi Medical College,Xinjiang Shihezi,832002 P.R.China)(Department of Mathematics,Shanxi Normal University,Xi'an 710062 P.R.China) 石河子医学院新疆石河子 832002 陕西师范大学数学系陕西西安 710062

The purpose of this paper is to investigate the permanence and existence of positive periodic solution of a cooperative *** model is composed of two patches in which one of the two species can diffuse between the two patches while the other is confined to one patch and can not ***'s proved that the model is permanent under appropriate *** if the model is a periodic system,it can have a strictly positive periodic solution whice has global attractivity under some appropriateconditions.

关键词： Permanence ultimately bounded domain diffusion rate periodic action global attractivity

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Effect of molecular weight on the quality of poly(alpha-methylstyrene) mandrel

引用

Matter and Radiation at Extremes 2017年第4期2卷 197-203页

作者： Xiuyun Shangguan Sufen Chen Shuang Ma Meifang Liu Changhuan Tang Yong Yi Zhanwen Zhang School of Material Science and Engineering Southwest University of Science and TechnologyMianyang621010China Research Center of Laser Fusion CAEPP.O.Box 919-987Mianyang621900China

Hollow poly(alpha-methylstyrene)(PAMS)shows application in inertial confinement fusion experiments as the degradable mandrels of glow plasma polymer ***,the molecular weight of PAMS has great influence on the quality of *** this work,this influence was systematically studied using several PAMS samples with different molecular *** PAMS shells with 900 mm inner diameter and different wall thickness,when the molecular weight of PAMS is in the range of 300e500 kg·mol^(-1),perfect sphericity and good wall thickness uniformity can be *** contrast,when increasing molecular weight to 800 kg·mol^(-1),the sphericity and the wall thickness uniformity become ***,compared with the wall uniformity,the sphericity of PAMS shells was much less sensitive to the molecular *** results also showed that the stability of W1/O compound droplets of PAMS shells were less affected by the molecular *** was revealed that the wall uniformity and the sphericity of the PAMS shells were associated with the diffusion rates of fluorobenzene(FB).

关键词： Poly(alpha-methylstyrene) Molecular weight Sphericity Wall thickness uniformity diffusion rate

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

An Optimized Parameter of Hydrogel for a Seven-Day Release of a Drug

引用

Journal of Biomaterials and Nanobiotechnology 2020年第4期11卷 237-244页

作者： Zixuan Jiang International Department Nanjing Foreign Language School Nanjing China

Drug release is a crucial process in treatment. Conventional drug administration requires patient’s compliance and has the risk of overdosing. In order to control drug release, several potential materials are develo0ped. In this paper, we focus on hydrogel material and simulate drug release process in MATLAB. We optimize the parameter for a seven-day release of a drug. The results show that the diffusion coefficient at approximately 4.00E−11 could ensure medicine to diffuse around 7 days and maintain its effects.

关键词： Hydrogel diffusion rate Drug Release

来源：

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

突发事件中信息扩散模型的扩散规模与扩散速率研究

引用

管理科学 2019年第9期

作者：黄英

信息传播按可靠性区分为真实性和失真性，传统信息传播模型只考虑信息传播的时效性或有效性，对真实性与失真性信息的扩散规模和扩散速率未提出有效解释方式，文章利用考虑速度与失真的信息扩散模型（Bass），并运用于突发危机事件中。... 详细信息

信息传播按可靠性区分为真实性和失真性，传统信息传播模型只考虑信息传播的时效性或有效性，对真实性与失真性信息的扩散规模和扩散速率未提出有效解释方式，文章利用考虑速度与失真的信息扩散模型（Bass），并运用于突发危机事件中。得出以下结论，第一，模仿系数q对真实信息扩散规模与扩散速率有显著作用，与失真信息没有线性关系。第二，官方发布T与失真信息的扩散规模和扩散速率呈反比例关系，与真实信息的扩散规模和扩散速率呈正比例关系。第三，真实率a只对口头传播中的扩散规模产生正相影响。第四，考虑失真信息后，动态系数r与信息传播速率由直线线性关系转换为曲线线性关系。

关键词：突发事件信息扩散模型(Bass) 模仿系数扩散速率 emergencies information diffusion model(Bass) imitation coefficient diffusion rate

来源：人大复印报刊资料评论

在线全文

人大复印报刊资料

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：