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Synergistic Effects in CNTs-PdAu/Pt Trimetallic Nanoparticles with High Electrocatalytic Activity and Stability
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作者 Xin-Lei Cai Chang-Hai Liu +7 位作者 Jie Liu Ying Lu Ya-Nan Zhong Kai-Qi Nie Jian-Long Xu Xu Gao Xu-Hui Sun Sui-Dong Wang 《纳微快报:英文版》 CAS 2017年第4期129-138,共10页
We present a straightforward physical approach for synthesizing multiwalled carbon nanotubes(CNTs)-Pd Au/Pt trimetallic nanoparticles(NPs), which allows predesign and control of the metal compositional ratio by si... We present a straightforward physical approach for synthesizing multiwalled carbon nanotubes(CNTs)-Pd Au/Pt trimetallic nanoparticles(NPs), which allows predesign and control of the metal compositional ratio by simply adjusting the sputtering targets and conditions. The small-sized CNTs-Pd Au/Pt NPs(3 nm, Pd/Au/Pt ratio of 3:1:2) act as nanocatalysts for the methanol oxidationreaction(MOR), showing excellent performance with electrocatalytic peak current of 4.4 A mg-1 Pt and high stability over 7000 s. The electrocatalytic activity and stability of the Pd Au/Pt trimetallic NPs are much superior to those of the corresponding Pd/Pt and Au/Pt bimetallic NPs,as well as a commercial Pt/C catalyst. Systematic investigation of the microscopic, crystalline, and electronic structure of the Pd Au/Pt NPs reveals alloying and charge redistribution in the Pd Au/Pt NPs, which are responsible for the promotion of the electrocatalytic performance. 展开更多
Preparation and Visible-Light Photocatalytic Activity of FeTPP-Cr-TiO2 Microspheres 预览
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作者 Bing-hua Yao Chao Peng +3 位作者 Yang-qing He Wen Zhang Yan Yu Ting Zhang 《化学物理学报》 SCIE CAS CSCD 2016年第6期717-724,I0002共9页
Tetraphenyl 卟啉铁(FeTPP ) 被选择敏化 Cr 做的 TiO <sub>2</sub>(Cr-TiO <sub>2</sub>) nanoparticles,有优秀可见光的 photocatalytic 活动的新奇 multimodified 光催化剂 FeTPP-Cr-TiO <sub>2</... Tetraphenyl 卟啉铁(FeTPP ) 被选择敏化 Cr 做的 TiO <sub>2</sub>(Cr-TiO <sub>2</sub>) nanoparticles,有优秀可见光的 photocatalytic 活动的新奇 multimodified 光催化剂 FeTPP-Cr-TiO <sub>2</sub> 成功地被综合。FeTPP-Cr-TiO <sub>2</sub> microspheres 被 X 光检查衍射描绘, Fourier 变换红外线的光谱学,扫描电子显微镜学, X 光检查光电子光谱学,紫外力的弥漫的反射系列和 N <sub>2</sub> 吸附解吸附作用等温线。FeTPP-Cr-TiO <sub>2</sub> 的 photocatalytic 活动被甲又蓝色的降级用 Xe 灯(150 W ) 在照耀下面在水的答案评估。结果证明 FeTPP-Cr-TiO <sub>2</sub> multimodified 光催化剂是有高特定的表面区域的锐钛矿阶段(74.7 m <sup>2</sup>/g), 和展出更高的 photocatalytic 降级效率比 Cr-TiO <sub>2</sub> 和 FeTPP-TiO <sub>2</sub> 。三 quinolone 抗菌素(lomefloxacin, norfloxacin,和 ofloxacin ) 的 photocatalytic 降级进一步在废水处理为催化剂的实际申请的可行性被估计。有 FeTPP-Cr-TiO <sub>2</sub> 的抗菌素的 photodegradation 完成了相当高的降级率,所有跟随了假一阶的反应模型,和 3.02 府寬謹穆食J?k,是合乎需要的吗? 展开更多
关键词 光催化活性 微球 喹诺酮类抗生素 可见光 傅里叶变换红外光谱 光催化降解 X射线光电子能谱 吸附-脱附等温线
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Effects Associated with Nanostructure Fabrication Using In Situ Liquid Cell TEM Technology
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作者 Xin Chen Lihui Zhou +4 位作者 Ping Wang Hongliang Cao Xiaoli Miao Feifei Wei Xia Chen 《纳微快报:英文版》 CAS 2015年第4期385-391,共7页
We studied silicon,carbon,and SiC xnanostructures fabricated using liquid-phase electron-beam-induced deposition technology in transmission electron microscopy systems.Nanodots obtained from fixed electron beam irradi... We studied silicon,carbon,and SiC xnanostructures fabricated using liquid-phase electron-beam-induced deposition technology in transmission electron microscopy systems.Nanodots obtained from fixed electron beam irradiation followed a universal size versus beam dose trend,with precursor concentrations from pure Si Cl4to 0%SiC l4in CH2Cl2,and electron beam intensity ranges of two orders of magnitude,showing good controllability of the deposition.Secondary electrons contributed to the determination of the lateral sizes of the nanostructures,while the primary beam appeared to have an effect in reducing the vertical growth rate.These results can be used to generate donut-shaped nanostructures.Using a scanning electron beam,line structures with both branched and unbranched morphologies were also obtained.The liquid-phase electron-beaminduced deposition technology is shown to be an effective tool for advanced nanostructured material generation. 展开更多
Pore structure and mechanical properties of directionally solidified porous aluminum alloys
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作者 KomissarchukOlga XuZhengbin +2 位作者 HaoHai ZhangXinglu VladimirKarpov 《中国铸造:英文版》 SCIE CAS 2014年第1期1-7,共7页
Porous aluminum alloys produced by the metal-gas eutectic method or GASAR process need to be performed under a certain pressure of hydrogen, and to carry over melt to a tailor-made apparatus that ensures directional s... Porous aluminum alloys produced by the metal-gas eutectic method or GASAR process need to be performed under a certain pressure of hydrogen, and to carry over melt to a tailor-made apparatus that ensures directional solidif ication. Hydrogen is driven out of the melt, and then the quasi-cylindrical pores normal to the solidif ication front are usually formed. In the research, the effects of processing parameters(saturation pressure, solidif ication pressure, temperature, and holding time) on the pore structure and porosity of porous aluminum alloys were analyzed. The mechanical properties of Al-Mg alloys were studied by the compressive tests, and the advantages of the porous structure were indicated. By using the GASAR method, pure aluminum, Al-3wt.%Mg, Al-6wt.%Mg and Al-35wt.%Mg alloys with oriented pores have been successfully produced under processing conditions of varying gas pressure, and the relationship between the f inal pore structure and the solidif ication pressure, as well as the inf luences of Mg quantity on the pore size, porosity and mechanical properties of AlMg alloy were investigated. The results show that a higher pressure of solidif ication tends to yield smaller pores in aluminum and its alloys. In the case of Al-Mg alloys, it was proved that with the increasing of Mg amount, the mechanical properties of the alloys sharply deteriorate. However, since Al-3%Mg and Al-6wt.%Mg alloys are ductile metals, their porous samples have greater compressive strength than that of the dense samples due to the existence of pores. It gives the opportunity to use them in industry at the same conditions as dense alloys with savings in weight and material consumption. 展开更多
Numerical simulation on multiple pouring process for a 292 t steel ingot
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作者 TuWutao ZhangXiong +1 位作者 ShenHoufa LiuBaicheng 《中国铸造:英文版》 SCIE CAS 2014年第1期52-58,共7页
A ladle-tundish-mould transportation model considering the entire multiple pouring(MP) process is proposed. Numerical simulation is carried out to study the carbon distribution and variation in both the tundish and th... A ladle-tundish-mould transportation model considering the entire multiple pouring(MP) process is proposed. Numerical simulation is carried out to study the carbon distribution and variation in both the tundish and the mould for making a 292 t steel ingot. Firstly, the fluid flow as well as the heat and mass transfer of the molten steel in the tundish is simulated based on the multiphase transient turbulence model. Then, the carbon mixing in the mould is calculated by using the species concentration at the tundish outlet as the inlet condition during the teeming process. The results show a high concentration of carbon at the bottom and a low concentration of carbon at the top of the mould after a MP process with carbon content high in the first ladle and low in the last ladle. Such carbon concentration distribution would help reduce the negative segregation at the bottom and the positive segregation at the top of the solidified ingot. 展开更多
Abnormal Visible Luminescence Mechanism of Tb^3+-Yb^3+ Codoped SiOu-Al2O3-CaF2 Glass Studied by Time-Resolved Spectra
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作者 段倩倩 赵华 +3 位作者 张治国 菅傲群 桑胜波 张文栋 《中国物理快报:英文版》 SCIE CAS CSCD 2014年第8期151-154,共4页
关键词 时间分辨光谱 发光机制 共掺杂 氟化钙 氧化铝 玻璃 能量传递机理 上转换发光
Effect of anions on stress corrosion cracking behaviors of ultra-high strength steel 23Co14Ni12Cr3Mo
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作者 刘建华 文陈 +2 位作者 于美 李松梅 王兵 《中南大学学报:英文版》 SCIE EI CAS 2014年第6期2117-2124,共8页
应力腐蚀行为上的氯化物,硫酸盐和碳酸盐阴离子的效果超离频强度钢 23Co14Ni12Cr3Mo 被裂开的应力腐蚀(SCC ) 学习用两倍伸臂横梁(DCB ) 的测试方法标本。SCC 形态学被使用扫描电子显微镜学(SEM ) 观察,腐蚀产品的作文被使用精力分析... 应力腐蚀行为上的氯化物,硫酸盐和碳酸盐阴离子的效果超离频强度钢 23Co14Ni12Cr3Mo 被裂开的应力腐蚀(SCC ) 学习用两倍伸臂横梁(DCB ) 的测试方法标本。SCC 形态学被使用扫描电子显微镜学(SEM ) 观察,腐蚀产品的作文被使用精力分析散分光计(版本) 。裂缝在 NaCl 和 Na 宣传到分叉的结果表演<潜水艇class=“ a-plus-plus ”> 2 </sub >那么<潜水艇class=“ a-plus-plus ”> 4 </sub>答案,当时在 Na 的裂缝<潜水艇class=“ a-plus-plus ”> 2 </sub >公司<潜水艇class=“ a-plus-plus ”> 3 </sub>答案宣传负担方向。在 NaCl 答案的 SCC 率最高,当更低时在 Na <潜水艇class=“ a-plus-plus ”> 2 </sub >那么<潜水艇class=“ a-plus-plus ”>在 Na 的 4 </sub>答案和很少<潜水艇class=“ a-plus-plus ”> 2 </sub >公司<潜水艇class=“ a-plus-plus ”> 3 </sub>答案。从 SEM 形态学,伪劈开骨折在 NaCl 和 Na 被观察<潜水艇class=“ a-plus-plus ”> 2 </sub >那么<潜水艇class=“ a-plus-plus ”> 4 个</sub>答案,但是 intergranular 在 Na 展示<潜水艇class=“ a-plus-plus ”> 2 </sub >公司<潜水艇class=“ a-plus-plus ”> 3 </sub>答案。钢 23Co14Ni12Cr3Mo 的 SCC 上的阴离子效果的机制被使用完整的沉浸测试和电气化学的大小学习。 展开更多
关键词 应力腐蚀开裂 超高强度钢 腐蚀行为 离子对 NA2SO4 NaCl溶液 碳酸钠溶液 NA2CO3
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Piezotronics and piezo-phototronics: fundamentals and applications
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作者 Zhong Lin Wang Wenzhuo Wu 《国家科学评论:英文版》 2014年第1期62-90,共29页
Technology advancement that can provide new solutions and enable augmented capabilities to complementary metal–oxide–semiconductor(CMOS)-based technology,such as active and adaptive interaction between machine and h... Technology advancement that can provide new solutions and enable augmented capabilities to complementary metal–oxide–semiconductor(CMOS)-based technology,such as active and adaptive interaction between machine and human/ambient,is highly desired.Piezotronic nanodevices and integrated systems exhibit potential in achieving these application goals.Utilizing the gating efect of piezopotential over carrier behaviors in piezoelectric semiconductor materials under externally applied deformation,the piezoelectric and semiconducting properties together with optoelectronic excitation processes can be coupled in these materials for the investigation of novel fundamental physics and the implementation of unprecedented applications.Piezopotential is created by the strain-induced ionic polarization in the piezoelectric semiconducting crystal.Piezotronics deal with the devices fabricated using the piezopotential as a‘gate’voltage to tune/control charge-carrier transport across the metal–semiconductor contact or the p–n junction.Piezo-phototronics is to use the piezopotential for controlling the carrier generation,transport,separation and/or recombination for improving the performance of optoelectronic devices.his review intends to provide an overview of the rapid progress in the emerging ields of piezotronics and piezo-phototronics.he concepts and results presented in this review show promises for implementing novel nano-electromechanical devices and integrating with micro/nano-electromechanical system technology to achieve augmented functionalities to the state-of-the-art CMOS technology that may ind applications in the human–machine interfacing,active lexible/stretchable electronics,sensing,energy harvesting,biomedical diagnosis/therapy,and prosthetics. 展开更多
Influences of different degassing processes on refining effect and properties of 4004AI alloy
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作者 WangLiping CaoGuojian +2 位作者 GuoErjun WangGuojun LuXinyu 《中国铸造:英文版》 SCIE CAS 2013年第2期104-107,共4页
In order to improve the plasticity of 4004 Al alloy and subsequently the productivity of 4004 Al foil, the research studied in detail the influence of the rotary impeller degassing process on the refining effect of 40... In order to improve the plasticity of 4004 Al alloy and subsequently the productivity of 4004 Al foil, the research studied in detail the influence of the rotary impeller degassing process on the refining effect of 4004 Al alloy, in which the impacts of four major parameters: gas flow, rotational speed, refining time, and stewing time, on degassing rate of 4004 Al alloy was systematically studied by using an orthogonal experiment methodology. Results show that the rotational speed has the greatest impact on the degassing of 4004 Al alloy, followed by gas flow and refining time; stewing time has the least impact. The optimum purification parameters obtained by current orthogonal analysis were: rotor speed of 500 r·min-1, inert gas flow of 0.4 mL·h-1, refining time of 15 min, and stewing time of 6 min. Degassing rate using the optimum parameters reaches 68%. In addition, the comparison experiments among C2Cl6 refining, rotary impeller degassing, and combined treatment of C2Cl6 refining and rotary impeller degassing for 4004 Al alloy were performed. The experimental data indicated that the combined treatment of C2Cl6 refining and rotary impeller degassing has the best degassing effect. Degassing rate of C2Cl6 refining, rotary impeller degassing and combined refining treatment is 39%, 69.1% and 76.9%, respectively. The mechanical properties of the specimen refined by rotary impeller degassing were higher than those by C2Cl6 refining, but lower than those by combined refining treatment. 展开更多
Numerical simulation of transport phenomena in continuous casting of steel plates with electromagnetic brake
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作者 龚海军 李新中 +2 位作者 茄菊红 范学燚 徐达鸣 《哈尔滨工业大学学报:英文版》 EI CAS 2012年第6期6-12,共7页
The present work numerically investigates two-dimensional (2-D) solidification transport phenomena (EM-STP) during continuous casting (CC) process in the absence and the presence of static magnetic fields (SMFs), base... The present work numerically investigates two-dimensional (2-D) solidification transport phenomena (EM-STP) during continuous casting (CC) process in the absence and the presence of static magnetic fields (SMFs), based on a unified numerical model. For the purpose of controlling vortexes, the electromagnetic brake (EMBR) effects of various SMFs under the given depth of submerged entry nozzle (SEN) and the same casting velocity V0 are investigated. ANSYS software is used to analyze the SMFs that applied to the EMCC process, and then a data-conversion program based on the principle of linear interpolation proposed previously is used to deal with the issue of data-format-matching between FEM and FVM. The simulation results indicate that, an appropriate SMF can effectively suppress the bulk liquid flow in CC-process of steel plate, and with increase of the intensity of applied magnetic fields, the vortexes become weaker and the oscillating amplitude of impinging jet decreases. Based on the knowledge gained from the EMCC-STP analysis and by comparing the results with the applied magnetic fields with those without magnetic fields, it is found that a SMF with |Bmax|=55×10-3 T can meet the need of braking, and consequently improve the quality of casting by reducing the penetration of non-metallic inclusions, as well as avoiding breakout, macro-segregation and crack ultimately. 展开更多
关键词 金属压力加工 轧制 拉制 电磁成型
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Preparation of BN/SiO2 ceramics by PIP method 被引量:1
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作者 王静 温广武 孟庆昌 《中南工业大学学报:英文版》 2005年第1期 31-34,共4页
The precursor infiltration and pyrolysis(PIP) method for preparation of BN/SiO2 composites was used to improve mechanical properties, dielectric properties and feasibility of high temperature dielectric parts with lar... The precursor infiltration and pyrolysis(PIP) method for preparation of BN/SiO2 composites was used to improve mechanical properties, dielectric properties and feasibility of high temperature dielectric parts with large dimensions and complex shapes. In the processing procedure, the porous BN ceramic matrix was first successfully prepared by compacting the mixed powders of B and BN and then sintering them at a certain temperature under normal pressure of N2.The polycarbosilane(PCS) solution was vacuum infiltrated into porous BN ceramics at the room temperature and then at 800 ℃ in the air to depolimerize out amorphous SiO2, and sintered further at 1 300 ℃ in N2 to get BN/SiO2 composites. The microstructure of materials was studied by means of X-ray diffraction and electron probe micro analysis. The thermo-decomposition mechanism of PCS was investigated by a TG-DTA and infrared (IR) spectrum analysis. The flexural strengths were measured by the three-point bending method. The dielectric constant and the loss tangent were measured by the wave-guide method. The results show BN/SiO2 composites were fabricated. The obtained composites posses a flexural strength of 61.9693.31 MPa, the dielectric constant in the range of 3.503.78 and the order of magnitude of the loss tangent at 10-3, which are good for the high temperature dielectric parts with large size and complex shapes. 展开更多
关键词 BN/SiO2 PIP 陶瓷技术 电介质 CMC
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Kinetics of Internal Oxidation of Cu-Al Alloy Plate 预览
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作者 SONGKexing XINGJiandong +2 位作者 TIANBaohong LIUPing DONGQiming 《武汉理工大学学报:材料科学英文版》 SCIE EI CAS 2005年第1期 13-16,共4页
The kinetics of internal oxidation of dilute Cu-Al alloys, containing up to 2.214% molar fraction Al, was investigated over the temperature range of 1023K to 1273K, and the depth of internal oxidation was measured by ... The kinetics of internal oxidation of dilute Cu-Al alloys, containing up to 2.214% molar fraction Al, was investigated over the temperature range of 1023K to 1273K, and the depth of internal oxidation was measured by microscopies. A modified rate equation was derived to describe the kinetics of internal oxidation of Cu-Al alloy plate.Based on the derived equation, the permeability of oxygen in solid copper was obtained from the internal oxidation measurements. The experimental results show that the depth of the internal oxidation is a parabolic function of time, there is no evidence for preferential diffusion along grain boundaries and an outer layer of pure copper was formed on the external surface of samples. 展开更多
关键词 CU-AL合金 内氧化 动力学 扩散
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Thermodynamic properties of ultra-small metallic particles
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作者 程南璞 曾苏民 陈志谦 《中国物理B:英文版》 SCIE EI CAS 2005年第7期1444-1448,共5页
The thermodynamic properties of ultra-small metallic particles within an ensemble are affected by the level distribution and the level correlation between the discrete electronic energy levels. The specific heat and ... The thermodynamic properties of ultra-small metallic particles within an ensemble are affected by the level distribution and the level correlation between the discrete electronic energy levels. The specific heat and spin susceptibility of ultra~small metallic particles in the canonical ensemble with an odd or even number of electrons are numerically calculated by considering the effects of the level statistics, and their behaviour at low and high temperatures is also discussed. As an example, the specific heat and spin susceptibility of nano-Al particles are calculated numerically in this paper. 展开更多
关键词 金属颗粒 特殊加热 自旋磁化系数 热力学性质
Computer Simulation of the Interphase Boundary Evolution in Ni75AlxV25-x Alloy 预览
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作者 YongshengLI ZhengCHEN +1 位作者 YanliLU YongxinWANG 《材料科学技术:英文版》 SCIE EI CAS 2005年第3期395-398,共4页
The interphase boundary evolution of ordered phase in Ni75AlxV25-x alloy during precipitation was simulated on atomic-scale based on the microscopic phase-field dynamic model. The results show that the second phase pr... The interphase boundary evolution of ordered phase in Ni75AlxV25-x alloy during precipitation was simulated on atomic-scale based on the microscopic phase-field dynamic model. The results show that the second phase precipitated from the interphase boundary formed by the first phase and the disordered matrix at high temperature, and from the interphase boundaries of the first phase at low temperature. L12 phase had obvious selective orientation when precipitated from the interphase boundaries of D022. L12 phase nucleated easily at the interphase boundaries formed by [10] and [01] directions of D022 projection along [001] direction, and grew easily at [10] direction. There was no the selective orientation when L12 phase precipitated from the interphase boundary formed by D022 and the disordered matrix. D022 phase had the selective orientation when precipitated from the interphase boundaries of L12, and grew along the [10] direction. 展开更多
关键词 微观相区 原子标度 相间边界 计算机模拟 Ni75AlxV25-x合金
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Kinetic equation for internal oxidation of Cu-Al alloy cylinders 预览
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作者 KexingSong JiandongXing +2 位作者 BaohongTian PingLiu QimingDong 《北京科技大学学报:英文版》 2005年第3期 262-266,共5页
The kinetics of internal oxidation of Cu-Al alloy cylinders, containing up to 2.214mol% Al, were investigated in the temperature range of 1023 K to 1273 K, and the depth of internal oxidation was measured in the micro... The kinetics of internal oxidation of Cu-Al alloy cylinders, containing up to 2.214mol% Al, were investigated in the temperature range of 1023 K to 1273 K, and the depth of internal oxidation was measured in the microscopy. A kinetic equation was derived to describe the internal oxidation of Cu-Al alloy cylinders. For the internal oxidation of Cu-Al alloys employed in the synthesis of alumina dispersion strengthened copper, the kinetic equation can be simplified. The derived equation was checked experimentally by means of oxidation depth measurements and the results show that the derived equation is exact enough to describe the kinetics of internal oxidation of Cu-Al alloy cylinders. Based on this equation and the oxidation depth measurements, the permeability of oxygen in solid copper was obtained. Investigation also shows that there is no evidence for preferential diffusion along grain boundaries in the process of internal oxidation. 展开更多
关键词 动力平衡 汽缸 铜铝合金 内部氧化 显微结构
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Glass-Forming Ability of an Iron-Based Alloy Enhanced by Co Addition and Evaluated by a New Criterion 被引量:1
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作者 陈庆军 沈军 +3 位作者 范洪波 孙剑飞 黄永江 MCCARTNEYD.G. 《中国物理快报:英文版》 SCIE CAS 2005年第7期1736-1738,共3页
A new Fe-based alloy that can be cast into a fully amorphous rod with a diameter of at least 16mm by the conventional copper-mould casting technique is obtained by partially replacing Fe with Co in a previously report... A new Fe-based alloy that can be cast into a fully amorphous rod with a diameter of at least 16mm by the conventional copper-mould casting technique is obtained by partially replacing Fe with Co in a previously reported Fe-based bulk metallic glass. The preliminary thermodynamic analysis indicates that the Co-containing alloy has a significantly lower Gibbs free energy difference between the undercooled melt and the corresponding crystalline solid, compared to the Co-free alloy, reflecting the dramatic role of the Co addition in stabilizing the supercooled melt and facilitating glass formation in iron-based alloys. Here, a new criterion, derived from the classical nucleation and growth theory, is introduced to evaluate the glass-forming ability of Fe-based bulk metallic glasses. 展开更多
关键词 玻璃成型 离子铁基合金加固 热力学计算
Effect of Nb on the Mechanical Properties of Ti/Al2O3 Composite 预览
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作者 WANGZhi XUKun +2 位作者 SHENQiang WANGYingzi ZHANGLianmeng 《武汉理工大学学报:材料科学英文版》 SCIE EI CAS 2005年第1期 30-32,36,共4页
Ti/Al2O3 composite with improved mechanical properties was synthesized by the spark plasma sintering. The effect of Nb on the microstructure of the composite was analyzed by TEM, SEM and so on. The experimental result... Ti/Al2O3 composite with improved mechanical properties was synthesized by the spark plasma sintering. The effect of Nb on the microstructure of the composite was analyzed by TEM, SEM and so on. The experimental results indicate that the bending strength, fracture toughness, micro-hardness and relative density of the composite are 897.29MPa, 17.38MPa·m1/2, 17.13GPa and 99.24% respectively when adding 1.5vol%Nb. The bending strength is improved by reason of forming dislocation ring and transfering fracture mode from intergranular to mixture fracture of intergranular and transgranular. The crack propagating is mainly the deflection bridging. It indicates a reduction of crack driving force and an increase in crack growth resistance,which results in toughness enhanced. 展开更多
关键词 火花等离子体烧结 Ti/Al2O3合成物 机械特性
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Ring-closing Metathesis on an Allyl-terminated Carbosilane Dendrimer 预览
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作者 ChuanJianZHOU RuiFangGUAN +2 位作者 ShengYuFENG DavidJ.BERG StephenR.STOBART 《中国化学快报:英文版》 SCIE CAS 2005年第1期 4-6,共3页
Grubbs' catalyst was used to prepare a series of carbosilane dendrimers with silacyclopentene peripheral groups. It was found that ring closing metathesis reaction was influenced strongly by the reaction temperatu... Grubbs' catalyst was used to prepare a series of carbosilane dendrimers with silacyclopentene peripheral groups. It was found that ring closing metathesis reaction was influenced strongly by the reaction temperature and the amount of catalyst. 展开更多
关键词 闭环反应 烯丙基 碳硅烷树枝状聚合体 催化剂 反应温度
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Optimization analysis on gap size of molding for Pb-GF composite wire
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作者 房文斌 孙宏飞 +2 位作者 耿耀宏 王尔德 韩飞 《中南工业大学学报:英文版》 2005年第1期 17-21,共5页
Under the condition of equal flow, the maximum and minimum theoretical values of gap size were studied and an estimation equation was established for the clad extrusion of the brittle core cladded by plastic metal mat... Under the condition of equal flow, the maximum and minimum theoretical values of gap size were studied and an estimation equation was established for the clad extrusion of the brittle core cladded by plastic metal materials. The results show that the gap size is a key parameter for the continuous clad extrusion and the molding speed. Its maximum value (Hmax) is 0.24 mm and the minimum one (Hmin) is 0.12 mm. At a gap size of 0.18 mm, the maximum of metal extrusion per unit of time and the optimal coating speed can be obtained. 展开更多
关键词 玻璃纤维 双金属丝 挤压成形 间隙尺寸
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Fracture toughness and safety assessment of X65 offshore pipeline welded joints 预览
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作者 张莉 张玉凤 +1 位作者 霍立兴 邓彩艳 《中国焊接:英文版》 EI CAS 2005年第1期 33-37,共5页
In this investigation, the mechanical properties and low-temperature fracture toughness of API 5L X65 offshore pipeline welded joints were studied. Structure Integrity Assessment Procedure (SINTAP)-Failure Assessment ... In this investigation, the mechanical properties and low-temperature fracture toughness of API 5L X65 offshore pipeline welded joints were studied. Structure Integrity Assessment Procedure (SINTAP)-Failure Assessment Diagram (FAD) method was applied to the pipe structure with surface flaw at the weld toe. According to the ISO standard BS7448,the CTOD fracture toughness of the welded joints was determined at the temperature of 0℃. For the heat-affected zone (HAZ) specimens, post-test metallographic analysis was performed to verify that the tip of the crack was located in the coarse crystal zone in order to confirm the validity of the above results. The failure lines of analysis level 1 and 3 of weld metal were derived from the results of the mechanical property test. The assessment was performed, considering the maximum lay stress, residual stress conservatively assumed to be uniform tensile stress, and minimum CTOD value. The results of the assessment showed that pipeline structure with a surface flaw ( the height and length are respectively 2. 2 mm and 5 mm) at the weld toe is safe. This study lays the foundation of application of SINTAP to pipeline structure assessment. 展开更多
关键词 低温破裂韧性 SINTAP 安全处理 管道焊接 结构检测
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