检索结果-南通市图书馆

Biaxial strained dual-phase palladium-copper bimetal boosts formic acid electrooxidation

Nano Research 2022年第1期15卷 280-284页

作者： Jiarun Geng Zhuo Zhu Youxuan Ni Haixia Li Fangyi Cheng Fujun Li Jun Chen Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Renewable Energy Conversion and Storage Center(RECAST)College of ChemistryNankai UniversityTianjin 300071China

Surface strain engineering is considered as an effective strategy to promote the electrocatalytic properties of noble metal ***,we construct a dual-phase palladium-copper(DP-PdCu)bimetallic electrocatalyst with remarkable biaxial strain via a one-pot wet-chemical approach for formic acid *** biaxial strain originates from the lattice mismatch between the disordered face-centered cubic(FCC)phase and ordered body-centered cubic(BCC)phase in each of DP-PdCu:*** proportion of FCC and BCC phases and size of PdCu nanoparticles are dependent on the addition amount of:capping agent,cetyltrimethylammonium bromide(CTAB).Density functional theory calculations reveal the downshift of d-band:center of Pd atoms due to the interfacial strain,which weakens the adsorption strength of undesired *** merit the,DP-PdCu catalyst with superior mass activity of 0.55 A·mg_(pd)^(-1) and specific activity of 1.91 mA·cm_(pd)^(-2) toward formic acid oxidation,outperforming the single FCC/EICC PdCu and commercial Pd/C *** will provide new insights into the structure design of high-performance electrocatalysts via strain engineering.

关键词： palladium-copper dual phase biaxial strain formic acid oxidation size-dependence

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

A well-posed Euler-Bernoulli beam model incorporating nonlocality and surface energy effect

引用

Applied Mathematics and Mechanics(English Edition) 2019年第11期40卷 1561-1588页

作者： Xiaowu ZHU Li LI School of Statistics and Mathematics Zhongnan University of Economics and LawWuhan 430073China State Key Laboratory of Digital Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

This study shows that it is possible to develop a well-posed size-dependent model by considering the effect of both nonlocality and surface energy,and the model can provide another effective way of nanomechanics for *** a practical but simple problem (an Euler-Bernoulli beam model under bending),the ill-posed issue of the pure nonlocal integral elasticity can be ***,a well-posed governing equation can be developed for the Euler-Bernoulli beams when considering both the pure nonlocal integral elasticity and surface ***,closed-form solutions are found for the deflections of clamped-clamped (C-C),simply-supported (S-S) and cantilever (C-F) nano-/*** effective elastic moduli are obtained in terms of the closed-form solutions since the transfer of physical quantities in the transition region is an important problem for span-scale modeling *** nonlocal integral and surface elasticities are adopted to examine the size-dependence of the effective moduli and deflection of Ag beams.

关键词： nonlocal integral elasticity bending size-dependence effect surface elasticity

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

THREE-DIMENSIONAL MODELING FOR THIN PLATE-LIKE STRUCTURES INCLUDING SURFACE EFFECTS BY USING STATE SPACE METHOD

引用

Acta Mechanica Solida Sinica 2010年第3期23卷 260-270页

作者： Hongyu Sheng Pin Lu Institute of Civil Engineering Hefei University of Technology Hefei 230009 China Institute of Materials Research and Engineering A ^＊STAR (Agency for Science Technology and Research) 3 Research Link Singapore 117602

A three-dimensional （3-D） approach based on the state space method is proposed to study size-dependent mechanical properties of ultra-thin plate-like elastic structures considering surface effects. The structure is modeled as a laminate composed of a bulk bounded with upper and bottom surface layers, which are allowed to have different material properties from the bulk layer. State equations, including the surface properties of the structure, can be established on the basis of 3-D fundamental elasticity to analyze the size-dependent static characteristics of the thin plate-like structure. Compared with two-dimensional plate theories based size-dependent models for thin film structures in literature, the present 3-D approach is exact, which can provide benchmark results to assess the accuracy of 2-D plate theories and various numerical approaches. To show the feasibility of the proposed approach, a 3-D analytical solution for a simply supported plate-like thin structure including surface layers is derived. An algorithm is proposed for the calculation of the state equations obtained to ensure that the numerical results can reveal the surface effects clearly even for extremely thin surface layers. Numerical examples are carried out to exhibit the surface effects and some discussions are provided based on the results obtained.

关键词： micro-structures surface effects size-dependence state equation three-dimensional modeling

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

Precise Large Deviations for Sums of Claim-size Vectors in a Two-dimensional size-dependent Renewal Risk Model

引用

Acta Mathematicae Applicatae Sinica 2021年第3期37卷 539-547页

作者： Ke-ang FU Xin-mei SHEN Hui-jie LI Department of Statistics Zhejiang University City CollegeHangzhou 310015China School of Mathematical Sciences Dalian University of TechnologyDalian 116024China Shunfeng Express Shanghai 200120China

Consider a two-dimensional renewal risk model,in which the claim sizes{Xk;k≥1}form a sequence of *** of a non-negative random vector whose two components are *** that the claim sizes and inter-arrival times form a sequence of *** pairs,with each pair obeying a dependence structure via the conditional distribution of the inter-arrival time given the subsequent claim size being *** a precise large-deviation formula of the aggregate amount of claims is obtained.

关键词： consistent variation extended regular variation large deviations size-dependence two-dimensional risk model

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

size Dependent Competition in Centric Diatoms as a Function of Nitrogen and Silicon Availability

引用

Open Journal of Marine Science 2012年第1期2卷 33-42页

作者： Paul D. van Ruth Jian G. Qin Alan J. Branford 不详

size dependent competition was examined in two marine centric diatoms, Coscinodiscus sp. and Thalassiosira rotula at various, and Si concentrations. The growth responses for both species to nutrient levels were evaluated using two forms of nitrogen (NH4 and NO3) and silicon in both monoculture and mixed culture conditions. Under single species culture, the impact of Si did not depend on N forms for both diatoms. The increase of NH4-N enhanced the growth of Coscinodiscus, but did not affect T. rotula. When NO3-N was the nitrogen source, cell densities of both species were significantly enhanced by increasing Si concentrations, but only T. rotula density was affected by increasing N concentration. When Coscinodiscus sp. and T. rotula grew in the same culture, Coscinodiscus sp. dominated in both N forms. The scale of the dominance of Coscinodiscus sp. over T. rotula increased with decreasing N and Si concentrations. In the competition experiment, when was the N source, both Coscinodiscus sp. and T. rotula were signifi- cantly affected by changes in N concentration, but only T. rotula was affected by Si. When NO3 was the N source, neither Coscinodiscus sp. nor T. rotula was affected by Si, but T. rotula was enhanced by N levels. Regardless the N form, the impact of Si on neither Coscinodiscus sp. nor T. rotula depended on N concentration. Our results indicate that large diatom species have a competitive advantage over small species, and both large and small species were sensitive to NH4-N limitation, but the small species was more sensitive to NO3-N limitation than the large species.

关键词： Diatoms size-dependence Nutrient Competition Nitrogen Silica

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

SURFACE EFFECTS ON THE PROPAGATION OF LOVE WAVES IN A MAGNETOELECTRIC NANOSTRUCTURE

SURFACE EFFECTS ON THE PROPAGATION OF LOVE WAVES IN A MAGNET...

引用

2016年全国压电和声波理论及器件应用研讨会

作者： Shi-jing GAO Le-le ZHANG Xiang-lin LIU Jin-xi LIU Department of Engineering Mechanics Shijiazhuang Tiedao University

Background, Motivation and Objective A nanostructure is defined as a material system or object where at least one of the dimensions lies below 100 nm. At this scale, material properties often exhibit obvious size effect. It is well known that surface effect is one of the most important structure characteristics of nanomaterials and plays a decisive role in the overall properties of materials. Therefore, considering the influence of surface effect is necessary to study the mechanical behavior of nanomaterials. The property of facilitating the conversion among mechanical energy, electric energy and magnetic energy makes magnetoelectric structures more advantageous than other traditional structures. As the nanomaterials are gradually attracting tremendous attention, magnetoelectric structures at the nanoscale show a bright prospect in fabricating nanodevices. In this paper, the dispersion characteristics of love waves propagating in a piezoelectric nanofilm on a piezomagnetic half-space with surface effects are investigated by using the surface piezoelectricity model. Statement of Contribution/Methods Firstly, the general solutions about the displacement and electric potential of both the piezoelectric nanofilm and the piezomagnetic half-space are solved by using the partial wave technique. Secondly, based on the surface piezoelectric constitutive theory, the existence of surface stresses exerting on the boundary conditions of the piezoelectric nanofilm is taken into account through the generalized Young-Laplace equations. Meanwhile, the two kinds of electrical boundary conditions, i.e., electrically shorted case and electrically open case, are both considered to get the dispersion equations. Finally, according to the dispersion equations with respect to wave number and wave velocity, the dispersion curves can be obtained. Furthermore, the impacts of surface parameters and film thickness on the propagation properties of love waves are analyzed in detail, and the disper

关键词： Surface effect Piezoelectric nanofilm Dispersion characteristic size-dependence Love wave

来源： cnki会议评论

在线全文

cnki会议

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：