检索结果-南通市图书馆

Bibliometric analysis of the literature from the mainland of China on animal-derived regenerative implantable medical devices

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

Frontiers of Materials Science 2014年第4期8卷 403-408页

作者： Hong-man WANG Fu-yao LI Institute for Medical Humanities Peking University Health Science Center Beijing 100191 China

Choosing animal-derived regenerative implantable medical devices based on tissue engineering technology as a research theme, this paper presents bibliometric analysis of relative literature from the mainland of China to understand such data as publication year and journal preference, authors＇ geographic location, research topics and core expertise to predict the research trends and provide an informed basis of decision making for researchers and clinicians.

关键词： animal-derived medical device tissue engineering regenerative implan-table medical device literature China's Mainland bibliometric analysis

Band structure design of semiconductors for enhanced photocatalytic activity: The case of TiO2

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

Progress in Natural Science:Materials International 2013年第4期23卷 402-407页

作者： Hui Yan Xudong Wang man yao Xiaojie yao School of Materials Science and Engineering Dalian University of Technology

General strategies are proposed by passivated co-doping in present paper to improve the photocatalytic activity of semiconductors for degradation of environmental *** ideal band gap of semiconductors for enhancement of photocatalytic activity can be lowered to match with visible light absorption and the location of the Conduction Band(CB) should be raised to meet the reducing *** we apply the strategy to anatase *** is predicted that nonmetal–metal co-doping TiO2can modify the catalyst band edges by raising the valence band(VB) edge signifcantly and making the CB edge increased 0.24 ***,the band gap for co-doping system should be narrowed to about2.72 eV.(N,Ta) is predicted to be the target donor–acceptor combination with the band gap of 2.71 eV,which red-shifts the TiO2absorption edge to 457.6 nm in visible *** band engineering principle will be ft to other wide-band-gap semiconductors for enhanced photocatalytic activity.

关键词： Anatase TiO2 Photocatalytic activity First principles calculation Electronic properties Co-doping

Temperature distribution and dynamic control of secondary cooling in slab continuous casting

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2009年第6期16卷 626-631页

作者： Liang-hang Guo Yong Tian man yao Hou-fa Shen School of Materials Science and Engineering Dalian University of Technology Dalian 116023 China Anshan Iron and Steel Group Anshan 114021 China Department of Mechanical Engineering Tsinghua University Beijing 100084 China

To predict and optimize the temperature distribution of slab continuous casting in steady operational state, a three-dimensional model （named ＂offline model＂） based on the heat transfer and solidification theories was developed. Both heat transfer and flux distribution characteristics of the nozzle sprays on the slab were considered, and the complicated boundary conditions, such as spray cooling, natural convection, thermal radiation as well as contact cooling of individual rolls were involved in the model. By using the calibrated caster dependent model factors, the calculated temperature and shell thickness accorded well with the measured. Furthermore, a dynamic secondary water cooling control system was also developed on the basis of a two-dimensional transient heat transfer model （named ＂online model＂） and incremental PID control algorithm to reduce slab surface temperature fluctuation in unsteady state. Compared with the traditional spray table control method, the present online model and dynamic PID control demonstrate a higher capability and flexibility to adjust cooling water flowrate and reduce slab surface temperature fluctuation when the casting speed is changed.

关键词： mathematical model slab temperature dynamic control continuous casting

Thermal conductivity prediction of MgAl2O4:a non-equilibrium molecular dynamics calculation

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2020年第5期27卷 500-505页

作者： Cheng-ming Ni Hua-wei Fan Xu-dong Wang man yao School of Materials Science and Engineering Dalian University of TechnologyDalian 116000LiaoningChina

Magnesium aluminate spinel(MgAl2O4)is widely used in steel metallurgy *** conductivity at high temperature signifcantly infuences the cooling process of blast furnace and the heat preservation of steel *** efect of external(temperature)and internal(antisite defect and grain boundary)factors on the thermal conductivity of MgAl2O4 was studied with non-equilibrium molecular *** main factors afecting the thermal conductivity of MgAl2O4 were *** the temperature range of 100-2000 K,the results showed that the thermal conductivity of MgAl2O4 changed from 11.54 to 4.95 W/(m K)with the increase in temperature and was relatively stable at the temperature above 1000 *** thermal conductivity of MgAl2O4 declined frst and then rose with the increase in the antisite defects,and the minimum value was 6.95 W/(m K)at the inversion parameter i=*** addition,grain boundaries reduced the thermal conductivity of MgAl2O4 by 20%-30%at temperature below 1000 K comparing with the non-grain boundary *** grain boundary rotation angle at temperature above 1000 K had less efect on the thermal conductivity than that below 1000 *** simulation scheme for thermal conductivity of MgAl2O4 can also be applied to the study of other nonmetallic ceramics.

关键词： Non-equilibrium molecular dynamics Thermal conductivity Magnesium aluminate spinel Antisite defect Grain boundary

Measurement of Attenuation of Ultrasonic Propagating through the Thin Layer Media with Time Delay Spectrum

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

Chinese Journal of Mechanical Engineering 2010年第1期23卷 129-134页

作者： WANG Xingguo CHANG Junjie SHAN Yingchun TIE Shaodong yao man XU Jiujun School of Materials Science and Engineering Dalian University of Technology Dalian 116024 China Transportation ＆ Logistics Engineering College Dalian Maritime University Dalian 116026 China

The ultrasonic attenuation coefficient is one of the most important acoustic parameters to character the performance of a thin layer media, but it can not be measured due to mutual superposition of multiple reflected waves at the same interface in ultrasonic testing. Ultrasonic pulse echo and lamb wave to evaluate the thin layer media can not obtain attenuation coefficient at present. In this paper, analytical method was used to study the acoustics characteristic of thin layer media with the ultrasonic echo testing. Meanwhile, the process of ultrasonic attenuation measurement was presented. Simulation and experimental investigation is focused on a thin layer of rubber. Attenuation coefficient was introduced and evaluation mathematics model was established by the two echoes cross-correlation with and without the thin layer media based on the time delay spectrum. It involved the parameters related to the acoustic properties of the thin layer media. Through calculating the sound velocity and acoustic impedance with the evaluation model, it can deduce the relation between the attenuation coefficient and the frequency. Through analyzing the simulation results, it indicated that the attenuation coefficients were invariable with the varying of the frequency. However, the attenuation coefficients increased with the frequency increasing by ultrasonic testing the thin layer of rubber. The reason was that the attenuation factor was not taken into account during the simulation. This method overcomes shortcomings that the traditional ultrasonic testing can not evaluate the thin layer media whose thickness is less than motivation wavelength. It is a new solution to study the attenuation characteristic and on-line nondestructive evaluation in the thin layer media.

关键词： ultrasonic testing the thin layer media time delay spectrum attenuation coefficient

Influence of Al-Ti-B addition on the microstructure and mechanical properties of A356 alloys

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2009年第2期28卷 181-186页

作者： Zhu man Yang Gencang yao Lijuan Cheng Suling Zhou yaohe NW Polytech Univ State Key Lab Solidificat Proc Xian 710072 Peoples R China

The mechanical properties (σb,σ0.2,and δ) and fracture behavior of tensile specimens of the refined A356 alloys were investigated as a function of the addition level of Al-Ti-B master alloy under both as-cast and T6 heat-treated conditions. The results show that as the addition level of Al-5Ti-1B master alloy increases from 0.1 wt.% to 5.0 wt.%,the mechanical properties of refined A356 alloys improve steadily and then decrease slightly under both as-cast and T6 heat-treated conditions. Also,they display exc...

关键词： Al-Ti-B master alloy mechanical properties fracture behavior aging precipitation phase

Analysis of Non-uniform Mechanical Behavior for a Continuous Casting Mold Based on Heat Flux from Inverse Problem

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2016年第2期23卷 83-91页

作者： Feng-ming DU Xu-dong WANG Yu LIU Tian-yi LI man yao School of Materials Science and Engineering Dalian University of Technology

The distortion of mold plates plays an important role in the formation of surface cracks on continuously cast steel products. To investigate the non-uniform distortion of a mold, a full-scale stress model of the mold was de veloped. An inverse algorithm was applied to calculate the heat flux using the temperatures measured by the thermo- couples buried inside the mold plates. Based on this, a full-scale, finite-element stress model, including four copper plates, a nickel layer and water slots in different depths, was built to determine the complex mechanical behavior of the continuous casting mold used to produce steel slabs. The heat flux calculated by the inverse algorithm was applied to the stress model to analyze the non-uniform mechanical behavior. The results showed that the stress and distortion distributions of the four copper plates were not symmetrical, which reflected the non-uniform distortion behaviors of copper plates, water slots, nickel layer and the corner region of the mold. The gap between the mold and the slab was increased because of the corner distortion, which was very important for the heat transfer of initial solidifying shell, and it may be a major reason for the slow cooling of the slab corner.

关键词： finite-element stress model inverse algorithm nickel layer water slots continuous casting mold

Comprehensive model for a slag bath in electroslag remelting process with a current-conductive mould

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2012年第4期19卷 303-311页

作者： Fu-bin Liu Xi-min Zang Zhou-hua Jiang Xin Geng man yao School of Materials and Metallurgy Northeastern University Shenyang 110819 China School of Materials and Metallurgy University of Science and Technology Liaoning Anshang 114051 China School of Materials Science and Engineering Dalian University of Technology Dalian 116024 China

A mathematical model was developed to describe the interaction of multiple physical fields in a slag bath during electroslag remelting （ESR） process with a current-conductive mould. The distributions of current density, magnetic induction intensity, electromagnetic force, Joule heating, fluid flow and temperature were simulated. The model was verified by temperature measurements during remelting 12CrMoVG steel with a slag of 50wt%-70wt% CaF2, 20wt%-30wt% CaO, 10wt%-20wt% A1203, and 〈10wt% SiO2 in a 600 mm diameter current-conductive mould. There is a good agreement between the calculated temperature results and the measured data in the slag bath. The calculated results show that the maximum values of current density, electromagnetic force and Joule heating are in the region between the comer electrodes and the conductivity element. The characteristics of current density distribution, magnetic induction intensity, electromagnetic force, Joule heating, velocity patterns and temperature profiles in the slag bath during ESR process with current-conductive mould were analyzed.

关键词： electroslag remelting mathematical models slag bath temperature distribution

Real Heat Flux Analysis of Continuously Casting Round Billet

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2008年第1期15卷 25-29页

作者： ZHAN Hui-ying WANG Xu-dong GUO Liang-liang yao man School of Material Science and Engineering Dalian University of Technology Dalian 116024 Liaoning China

The distributions of heat flux along the height and the circumferential direction of round billet mould were measured *** influence of casting speed,carbon content,powder,and pouring temperature on the average longitudinal and circumferential heat flux in the ＂high heat flux region＂ was *** experimental and analytical results provide a basis for an intelligent mould with online detection of defects,adjustment of operational parameters,optimization of the monitoring system,and even prediction of abnormal heat transfer.

关键词： continuous casting mould heat flux round billet