检索结果-南通市图书馆

Pressure-induced color change arising from transformation between intra-and inter-band transitions in LuH_(2±x)N_(y)

在线全文

学校读者我要写书评

暂无评论

Science china(Physics,Mechanics & Astronomy) 2024年第2期67卷 161-166页

作者： Zhe Liu Yingjie Zhang shenyang Huang Xue Ming Qing Li Chenghao Pan Yaomin Dai Xiaoxiang Zhou Xiyu Zhu Hugen Yan Hai-Hu Wen Center for Superconducting Physics and materials National Laboratory of Solid State Microstructures and Department of PhysicsNational Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China State Key Laboratory of Surface Physics Key Laboratory of Micro and Nano-Photonic Structures of the Ministry of EducationDepartment of PhysicsFudan UniversityShanghai 200433China

The pressure-induced color change in the nitrogen-doped lutetium hydride has triggered extensive discussions about the underlying physics and potential ***,we study the optical response of LuH_(2±x)N_(y)in a broad frequency range at ambient pressure and its evolution with pressure in the visible spectral *** broad-band optical spectra at ambient pressure reveal a Drude component associated with intra-band electronic transitions and two Lorentz components(L1 and L2)arising from inter-band electronic *** application of pressure causes a spectral weight transfer from L1 to the Drude component,leading to a blue shift of the plasma edge in the reflectivity spectrum alongside a reduction of the high-frequency *** results suggest that the pressure-induced color change in LuH_(2±x)N_(y)is closely related to the transformation between intra-and inter-band electronic transitions,providing new insights into the mechanism of the pressure-induced color change in LuH_(2±x)N_(y).

关键词： nitrogen-doped lutetium hydride optical spectroscopy high-pressure technique color change

Fabrication of Porous Bulk Metallic Glass

在线全文

学校读者我要写书评

暂无评论

Journal of materials Science & technology 2005年第6期21卷 788-790页

作者： Keqiang QIU+ and Yinglei REN school of materials Science and Engineering, shenyang university of technology, shenyang 110023, china school of materials Science and Engineering Shenyang University of Technology Shenyang 110023 China

An open-cell porous bulk metallic glass （BMG） with a diameter of at least 6 mm was fabricated by using an U-turn quartz tube and infiltration casting around soluble NaCI placeholders. The pore formation and glassy structure were examined by optical microscopy （OM）, scanning electron microscopy （SEM） and X-ray diffraction （XRD）. The results show that the pores or cells are connected to each other and the specimen is composed of a mostly glassy phase. This paper provides a suitable method for fabrication of porous BMG and BMG with larger size in diameter.

关键词： Porous bulk metallic glass U-turn quartz tube Infiltration casting

Nonisothermal Behavior of Oxidation of Natural Ilmenite Pellet

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2000年第3期19卷 222-226页

作者： Sun Kang (孙康) school of materials and Metallurgy,Northeastern university,shenyang 110006,china Northeastern Univ Shenyang China

The nonisothermal behavior of the oxidation of natural ilmenite pellets was interpreted in the light of a nonisothermal kinetic model which fits the experimental results very *** rate of the overall oxidation was predominantly controlled by the intrapellet diffusion of oxygen and the rate of heat transfer was mainly limited by the heat conduction through the product *** oxidation of natural ilmenite pellet can not be treated as an isothermal reaction system within the temperature range of 1073～ 1173K unless the concentration of oxygen in the gaseous reactants is less than 10 mol%.

关键词： Nonisothermal behavior Oxidation Ilmenite Kinetic model Rate controlling step

Study on Modification Mechanism of Rare Earth in ZA27 Cast Alloy with Electronic Theory and Molecular Dynamics Method

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of materials Science & technology 2004年第5期20卷 586-588页

作者： Guili LIU, Rongde LI and Zhenping ZHOUschool of materials Science and Engineering, shenyang university of technology, shenyang 110023, china Sch. of Mat. Sci. and Eng. Shenyang Univ. of Technol. Shenyang 110023 China

A model of liquid ZA27 cast alloy is established according to molecular dynamics theory and an atomic structural model of co-existent a phase and liquid is also presented by means of computer programming. Recursion method is adopted to calculate the electronic structure of RE (rare earth) in grains and around phase boundaries respectively. The calculation shows that RE is more stable around phase boundaries than in grains, which explains the fact that the solution of RE in a phase is less, and RE mainly aggregates in front of phase boundary. The calculations of bonding order integrals also show that RE in front of phases hardly solidify onto the grain surfaces as active element so as to prevent grains growth and refine the grains. As a result, the modification mechanism of RE may be explained from the view of electronic structure.

关键词： Atomic structural model Recursion method Electronic structure Modification mechanism Rare easth

A routing algorithm based on clusters and balanced use of energy for wireless sensor networks

在线全文

学校读者我要写书评

暂无评论

控制理论与应用（英文版） 2010年第1期8卷 81-85页

作者： Liang ZHANG,Xiangdong WANG,Shujiang LI(school of Information Science and Engineering,shenyang university of technology,shenyang liaoning 110178,china) school of Information Science and Engineering Shenyang University of Technology Shenyang Liaoning China

In a sensor network, data collected by different sensors are often correlated because they are observations of related phenomena. Efficient sensor data fusion is one of the most important issues in building real sensor networks. To balance energy cost, how to select a cluster head is a key problem that must be addressed. In this paper, we use a compression-centric data collection algorithm for use in wireless sensor networks. Also, we propose a balanced cluster head selection algorithm in each cluster. Simulation results are used to investigate the performance of the algorithm. Compared to the exhaustive search solutions, the proposed algorithm shows a significant improvement in power consumption.

关键词： Sensor networks Cluster Sink node Power consumption

Study on the Corrosion Resistance of Multiphase TRIP Steels

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2011年第S1期18卷 883-887页

作者： WANG Ji-jie 1,WU Di 2,LI Zhuang 1,GUO Xiang-min 1,HE Chun-lin 3,CAI Qing-kui 3 (1.school of materials Science and Engineering,shenyang university of Aeronautics and Astronautics,shenyang 110136,liaoning,china 2.State Key Laboratory of Rolling and Automation,Northeastern university,shenyang 110004,china 3.liaoning Province Key Laboratory for Advanced materials,shenyang university,shenyang 110044,liaoning,china) shenyang Univ Aeronaut & Astronaut Sch Mat Sci & Engn Shenyang 110136 Liaoning Peoples R China Northeastern Univ State Key Lab Rolling & Automat Shenyang 110004 Peoples R China shenyang Univ Liaoning Prov Key Lab Adv Mat Shenyang 110044 Liaoning Peoples R China

Multiphase TRIP (Transformation Induced Plasticity) steels are known to combine higher strength with higher *** this paper,the corrosion resistance of this steel has been has been investigated by accelerated corrosion tests,such as wet/dry cyclic corrosion and the weight loss in *** morphologies of their rust layers were observed by using scanning electron microscopy,and the corrosion performance of these steels was discussed by analyzing the protective *** results show that the corrosion rate of steel A is significantly greater than that of steels B and C in wet/dry cyclic corrosion and weight loss *** corrosion performance of conventional C-Mn-Si TRIP steel is deteriorated in both NaHSO 3 and 3.5 wt.% NaCl aqueous *** superior corrosion performance is exhibited for TRIP steel with low alloying contents due to its high thermodynamic *** enhancement of corrosion performance of TRIP steel is attributed to the additions of alloying elements,such as Al,Cu,Cr,Mo,Ni,*** alloying elements increase the compactness of rust layers,so electrochemical characteristic of TRIP steel is improved.

关键词： TRIP steel alloying element rust layer corrosion performance

Pattern scaling effect on the radiative properties of wafer's surface

在线全文

学校读者我要写书评

暂无评论

Science china(Technological Sciences) 2010年第7期53卷 1886-1892页

作者： WANG AiHua & CAI JiuJu school of materials and Metallurgy, Northeastern university, shenyang 110819, china school of materials and Metallurgy Northeastern University Shenyang China

This paper presents a parametric study of the radiative properties of patterned wafers with a polysilicon gate array on the Si substrate, considering the effect of wavelength and polarization. The finite-difference time-domain (FDTD) method was employed to examine the pattern scaling effect on the spectral absorptance via numerical solutions of the Maxwell's equations. The effective medium theory (EMT) was also used to help explain the absorptance predictions. While the gate sizes are very small compared to wavelength, the results show rather unusual phenomena. The absorptance calculated by EMT is in agreement with FDTD in the cases with small gate and period sizes. With the increase of period and decrease of the ratio of the gate width to the grating period, both EMT and FDTD results for the TM (transverse magnetic) mode approach to pure silicon since the grating effect diminishes. However, the error of EMT results for the TE mode in some cases becomes considerable due to the limitation of EMT, which requires the period to be significantly smaller than the wavelength. Besides, the TE (transverse electric) absorptance curve separates from that of plain Si when the wavelength equals the grating period, this is because the gate can interact with its neighbering region by diffraction and the diffraction effects are weak, when the wavelength is small. The peak absorptance can be attributed to the thin film effect. It shows that a slight increase in the gate height can drastically increase the absorptance and the increased gate height shifts the peak absorptance to longer wavelength due to the increase of optical path length in the effective thin film. This work is of great importance for optimization of advanced annealing techniques in semiconductor manufacturing.

关键词： finite-difference time-domain method effective medium theory radiative property resonance cavity effect patterned wafer

Modeling radiative properties of nanoscale patterned wafers

在线全文

学校读者我要写书评

暂无评论

Science china(Technological Sciences) 2010年第2期53卷 352-359页

作者： WANG AiHua & CAI JiuJu school of materials and Metallurgy, Northeastern university, shenyang 110004, china school of materials and Metallurgy Northeastern University Shenyang China

Temperature nonuniformity in rapid thermal processing of wafers is a critical problem facing the semiconductor industry. One cause of the problem is the nonuniform absorption of thermal radiation in patterned wafers where the optical properties vary across the wafer surface. This paper presents a parametric study of the radiative properties of patterned wafers, considering the effect of temperature, wavelength, and polarization. The finite-difference time-domain (FDTD) method is employed to examine the effect of various trench sizes on the radiative properties via numerically solving the Maxwell equations. The effective medium theory (EMT) is also used to help explain the absorptance prediction. The results show that in the cases with trench size variation, the resonance cavity effect may increase the absorptance as the trench width increases. And in the cases with trench size increasing at several different filling ratios, the absorptance does not change much at small filling ratio. The effects of the resonant cavity, diffraction, wave interferences on the spectral-directional absorptance were also discussed. This work is of great importance for optimization of advanced annealing techniques in semiconductor manufacturing.

关键词： finite-difference time-domain method effective medium theory radiative property periodic nanostructure

Influence of Controlled Rolling and Cooling Process on the Mechanical Properties of Low Carbon Cold Forging Steel

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2011年第S1期18卷 595-599页

作者： LI Zhuang 1,WU Di 2,ZHENG Hui 1,DONG Xue-xin 2 (1.school of materials Science and Engineering,shenyang university of Aeronautics and Astronautics,shenyang 110136,liaoning,china 2.State Key Laboratory of Rolling and Automation,Northeastern university,shenyang 110004,liaoning,china) shenyang Univ Aeronaut & Astronaut Sch Mat Sci & Engn Shenyang 110136 Liaoning Peoples R China Northeastern Univ State Key Lab Rolling & Automat Shenyang 110004 Liaoning Peoples R China

In the present paper,controlled rolling and cooling processing was conducted by using a laboratory hot rolling *** influence of different processing parameters on the mechanical properties of low carbon cold forging steel was *** results show that the faster cooling after the deformation (especially in low temperature rolling conditions) leads to the refinement of the ferrite *** specimen exhibits very good mechanical properties owing to the finer ferrite *** pearlite morphologies can also affect the mechanical properties of low carbon cold forging *** mechanical properties increase with decreasing final cooling temperature within the range from 650℃ to 570 ℃ due to the finer interlamellar spacing of pearlite *** mechanical properties of the specimens with fast cooling after the conventional rolling are not only better than those of the specimens with slow cooling after low temperature rolling,but also almost similar to those of the specimens with fast cooling after low temperature *** is suggested that fast cooling after high temperature rolling (the conventional rolling) process would be of important industrial value.

关键词： controlled rolling and cooling process low carbon cold forging steel fast cooling the finer ferrite grains mechanical properties