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Manufacture of Raney Ni catalyst with metastable Ni_2Al_3 by high energy milling

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中国有色金属学会会刊：英文版 1999年第3期9卷 562-565页

作者： Teng Ronghou(滕荣厚) 1. Sun Shijie(孙世杰) 1. Liu Silin(刘思林) 1. Liu Xuequan(柳学全) 1. Ma Ruzhang(马如璋) 2,Liu tao(刘涛) 3 1. Functional Materials Institute, Central Iron & Steel Research Institute, Beijing 1.0081. P.R.China 2. Depar 钢铁研究总院功能材料所北京 100081 钢铁研究总院功能材料所北京北京科技大学材料物理系北京 100083 中科院高能物理所北京 100039

The Ni Al alloy containing Cr, Fe additives were prepared as Raney Ni catalyst by high energy milling. The size and surface state of Ni Al alloy powder were studied by particle size analyzer and sanning electron microscopy, the structure was analyzed by XRD and Mssbauer methods. The results showed that after a high energy milling (HEM), the Ni Al alloy transforms to a nano scale NiAl structure with rich Al. By annealing the alloy, a metastable Ni 2Al 3 phase can be obtained.

关键词： Raney nickel catalyst nano crystal high energy milling

Kinematics and dynamics of the Mesozoic orogeny and late-orogenic extensional collapse in the Sino-Mongolian border areas

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Science China Earth Sciences 2005年第7期48卷 849-862页

作者： ZHENG Yadong 1.& WANG tao2 1. Key Laboratory of Orogenic Belts and Crustal Evolution (Peking University), Ministry of Education, Beijing 1.0871. China 2. Institute of Geology, Chinese Academy of Geological Sciences, Beijing 1.0037, China Key Laboratory of Orogenic Belts and Crustal Evolution (Peking University) Ministry of Education Beijing 100871 China Institute of Geology Chinese Academy of Geological Sciences Beijinq 100037 China

The Sino-Mongolian border areas underwent two important tectonic events during Mesozoic time after late Paleozoic orogeny: a late Triassic to earlier Jurassic contractional event that resulted in a large-scale south-vergent thrust during the orogeny and a late Jurassic-earlier Cretaceous extensional event in a north-south direction that formed a metamorphic core complex. The kinematic and dynamic analyses show that the thrust sheet moved southwards with a kinematic vorticity number of ca. -0.1. and sub-horizontal maximum compressive stress axis that belongs to a contraction-thickening shear. The upper plate of the late-orogenic detachment relatively moved in a 1.5°direction. The average kinematic vorticity in its earlier stage was 0.74 that belongs to simple shear dominated shearing and related to the maximum compressive stress axes dipping at ～66°, while the later average kinematic vorticity was ～0.55°that belongs to pure shear dominated shearing with sub-vertical maximum compressive stress axes. This suggests that the thrusting led to the crust thickened and the lower plate rocks that were originally located in the upper crust depressed through a brittle-ductile transition zone into the lower crust and became warmer. The heated rocks trended to uplift since their increasing volume and decreasing density while the loading of the upper-plate rocks increased due to the structural thickening. Under the combined effect of the loading and the thermal-uplifting, the ductile shear zone in between increased in its component of vertical pure shear. Once its pure-shear component exceeded its simple-shear one the ductile shear zone became an extension-thinned shear zone. This progressive transitional process reflects internal and essential temporal and spatial relationships: the extensional factor nucleated during the crust thickening by thrusting and increase of the extensional factor finally led to late-orogenic collapse.

关键词： Mesozoic thrusting,late-orogenic collapse,kinematic vorticity number,stress state.

Study on the bulk wave radiation of finite-length SAW devices using FEM/BEM

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Progress in Natural Science:Materials International 2005年第5期15卷 402-406页

作者： WANG Weibiao1.*, ZHANG Xiaodong1. SHUI Yongan1. ZHANG De1.and HAN tao2(1. State Key Laboratory of Modern Acoustics, Institute of Acoustics, Nanjing University, Nanjing 21.093, China 2. Shanghai Jiaotong University, Shanghai 200030, China) State Key Lab. of Modern Acoustics Inst. of Acoustics Nanjing Univ. Nanjing 210093 China Shanghai Jiaotong Univ. Shanghai 200030 China

Based on the distributions of stress and free charge on the interface of the surface acoustic wave (SAW) device calculated with the combination of boundary element method and finite element method(FEM/BEM), the power of each of the three possible bulk waves radiated by the SAW device is calculated, and their contributions to the overall input conductance are separated respectively. Moreover, the formula of angular distributions of their power radiation into the substrate is derived. Consider the effect of mass loading, the resistance density,defined as a scalar, is extended to generalized resistance densities which can be written as three 4×4 tensors and for which the formulas are derived. The bulk wave radiations for a synchronous one-port resonator on 42°Y-rotated Litao 3 are simulated. It is found that the radiated energy by slow shear wave contributes a very high proportion to input electrical energy in some frequency range.

关键词： SAW device bulk wave radiation FEM/BEM.

Parallel-pipelined Architecture of H.264 Deblocking Filter with Adaptive Dynamic Power

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Journal of Shanghai Jiaotong university(Science) 2010年第2期15卷 224-230页

作者：韦虎林涛 Department of Electronic Engineering Shanghai Jiaotong University Institute of Very Large Scale Integrated Circuits Tongji University

In H.264,the computational complexity and memory access of deblocking filter are variable and depend on the video contents. In this paper,a pipelined VLSI architecture of deblocking filter with adaptive dynamic power is proposed. It avoids redundant computations and memory access by precluding the blocks which can be skipped. And the vertical and horizontal edges are simultaneously processed in an advanced scan order to speed up the decoder. As a result,the dynamic power of the proposed architecture can be reduced (up to about 89%) adaptively for different videos. And the off-chip memory access is improved compared to the previous designs. Moreover,the processing capability of the proposed architecture is very appropriate for real-time deblocking of high-definition television (HDTV,1.20× 1.80 pixel/frame,30 frame/s video signals) video operation at 38 MHz,which significantly outperforms the previous designs from 1.25 times to 4.8 times.

关键词： deblocking filter adaptive dynamic power parallel processing pipeline H.264

Development of Deep Desulphurization Process for X65 HIC Resistant Pipeline Steel

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Journal of Iron and Steel Research International 2011年第S2期18卷 92-97页

作者： DENG Xu-yan1. ZOU Chang-dong1. ZHOU Yan-zhao1. XIA Qi1. HUANG Zhu-ping2, DING Zhen-tao2 (1. Steelmaking and Casting Group, Institute of Research of Iron and Steel of Jiangsu (Shasteel), Suzhou 21.625, Jiangsu, China 2. Hongfa Steelmaking Plant, Shasteel Group, Suzhou 21.625, Jiangsu, China) Inst Res Iron & Steel Jiangsu Shasteel Steelmaking & Casting Grp Suzhou 215625 Jiangsu Peoples R China Shasteel Grp Suzhou 215625 Jiangsu Peoples R China

The effect of ladle slag composition, bottom stirring intensity, and refining duration on desulphurization (De-S hereafter) behavior was investigated in ladle furnace (1.0t) through production data analysis and plant scale experiments. The results show that the ladle slag composition for deep De-S is w(CaO): 50%-55%, w(CaF2): 3%-7%, w(Al2O3): 20%-25%, w (SiO2) 1.%, w (MgO) 1.%, and w(FeO) 1.% to around 20%, within the selected period of 8 min with the increase of Ar flowrate of bottom blowing from 400 L/min to 600 L/min; sulfur can be reduced to less than 1. ppm from around 35 ppm within 20 min if the Ar flowrate is kept at 600 L/min; during steelmaking trial of X65 HIC resistant steel, the sulfur content of final product was controlled to be below 1. ppm when sulfur content of the melt at BOF blowing end was kept below 60 ppm, De-S was carried out with the above mentioned slag, and 600 L/min Ar stirring for more than 20 min.

关键词： ultra low sulfur LF De-S HIC resistant

Ti-Ni形状记忆合金复合悬摆减震系统性能试验研究

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振动与冲击 2017年第11期36卷 41-47页

作者：王社良余滨杉樊禹江杨涛西安建筑科技大学土木工程学院西安710055 长安大学建筑学院西安710061

系统研究了Ti-Ni形状记忆合金丝应力-应变曲线、特征点应力、耗能能力、等效阻尼比等随材料直径、应变幅值、加载循环次数的变化规律,结果表明:丝材直径的增加会导致SMA丝力学性能趋于劣化;当应变幅值为6%、加载循环次数达1.次时,可获... 详细信息

系统研究了Ti-Ni形状记忆合金丝应力-应变曲线、特征点应力、耗能能力、等效阻尼比等随材料直径、应变幅值、加载循环次数的变化规律,结果表明:丝材直径的增加会导致SMA丝力学性能趋于劣化;当应变幅值为6%、加载循环次数达1.次时,可获得滞回性能良好、工作稳定的SMA丝材。将训练后所得SMA丝材,利用其超弹性特性,结合调谐质量阻尼器基本工作原理,设计制作了一类可便于拆卸的SMA复合悬摆减震系统。针对该类减震系统,完成了相应的性能试验,分析了该系统自振频率、质量振子与受控结构间的相位关系、等效阻尼力随振子质量、摆杆长度的变化规律,结果表明:该减震系统在正弦波和真实地震激励下质量振子与受控体结构之间相位关系始终较好的保持在1.0°~1.0°之间;同时,等效阻尼力随外荷载幅值的增大,控制效果更加明显。综上,该系统能够简便应用于结构振动控制之中,并提供稳定、高效的阻尼力,从而保护结构免于强动力灾害。

关键词：超弹性特性形状记忆合金复合悬摆减震系统相位关系等效阻尼力

Feature extraction and classification of hyperspectral remote sensing image oriented to easy mixed-classified objects

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中国有色金属学会会刊：英文版 2005年第S1期15卷 168-171页

作者： ZHANG Lian-peng~1. LIU Guo-lin~2, JIANG tao~2 (1. Department of Territory Information and Surveying Engineering, Xuzhou Normal University, Xuzhou 221.09, China 2. Shandong University of Science and Technology, Tai’an 271.1.,China) Xuzhou Normal Univ Dept Terr Information & Surveying Engn Xuzhou 221009 Peoples R China Shandong Univ Sci & Technol Tai An 271019 Peoples R China

The classification of hyperspectral remote sensing data is an important problem theoretically and practically. With the increase of spectral bands, the separability of objects on remote sensing image should be improved. But the effects of traditional algorithm on feature extraction such as principal component analysis(PCA) is not so good for hyperspectral image. The key problem is that PCA can only represent the linear structure of data set; while the data clouds of different objects on hyperspectral image usually distribute on a nonlinear manifold. This paper established an algorithm of nonlinear feature extraction named as nonlinear principal poly lines, based on the algorithm, a classifier is constructed and the classification accuracy of hyperspectral image can be improved.

关键词： hyperspectral remote sensing feature extraction classification

5-(2-噻吩)-2-对甲苯基口恶唑的合成

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精细化工 2017年第2期34卷 203-206页

作者：周芸刘卉何艳陶李明湘南稀贵金属化合物及其应用湖南省重点实验室湘南学院化学生物与环境工程学院湖南郴州423000 湘南学院药学院湖南郴州423000

以2-溴-1.(2-噻吩)-1.乙酮(Ⅰ)和对甲基苯甲胺(Ⅱ)为原料,在碘与叔丁基过氧化氢(TBHP)的复合催化作用下,通过氧化环合反应合成了5-(2-噻吩)-2-对甲苯基口恶唑(Ⅲ)。产物结构经FTIR、NMR和MS表征,并对产物的生物活性进行了测试。结果显示... 详细信息

以2-溴-1.(2-噻吩)-1.乙酮(Ⅰ)和对甲基苯甲胺(Ⅱ)为原料,在碘与叔丁基过氧化氢(TBHP)的复合催化作用下,通过氧化环合反应合成了5-(2-噻吩)-2-对甲苯基口恶唑(Ⅲ)。产物结构经FTIR、NMR和MS表征,并对产物的生物活性进行了测试。结果显示:合成反应的最佳条件为n(Ⅰ)=1.mmol、n(Ⅱ)=1.3 mmol、n(I2)=0.2 mmol、n〔TBHP(质量分数55%)〕=1.2mmol、n(Na HCO3)=1.0 mmol,室温下反应1. h,产物收率为89.7%。抑菌圈测定结果显示:化合物Ⅲ对大肠杆菌的抑菌圈直径为21.9 mm,具有强的抑菌能力。

关键词： 2-溴-1.(2-噻吩)-1.乙酮对甲基苯甲胺 5-(2-噻吩)-2-对甲苯基口恶唑碘叔丁基过氧化氢医药原料

Modified methods of designing sliding surface in variable structure systems

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Journal of Harbin Institute of Technology(New Series) 1999年第4期6卷 1-6页

作者： FENG Yong 1. AN Cheng quan 1. LI tao 2 (1. Dept. of Electrical Engineering, Harbin Institute of Technology, Harbin 1.0001. China 2. Dept. of Automation, Tsinghua University, Beijing 1.0084, China)

This paper presents two modified methods of designing sliding surface in variable structure systems based on the mathematical equation established for the relationship between the steady state error of the system and the slope of the sliding surface. Replacing the switching function with the saturation function in the control signal, the methods can not only reduce the system steady state error, but also smooth chatterring in the variable structure systems.

关键词： variable structure systems (VSS) nonlinear systems sliding mode