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中国城镇居民收入和消费的协整分析

消费经济 2005年第2期21卷 16-19页

作者：张继海臧旭恒山东大学经济学院山东济南250100

本文利用误差修正模型对中国城镇居民收入和消费进行协整分析。通过协整分析实证分析了中国城镇居民消费和收入之间的短期波动和长期均衡关系。实证分析的结果表明中国城镇居民家庭实际收入和实际消费之间存在长期的协整关系,当期收入... 详细信息

本文利用误差修正模型对中国城镇居民收入和消费进行协整分析。通过协整分析实证分析了中国城镇居民消费和收入之间的短期波动和长期均衡关系。实证分析的结果表明中国城镇居民家庭实际收入和实际消费之间存在长期的协整关系,当期收入和长期均衡对居民消费都具有较强的制约作用。在长期中,收入增长是制约居民消费增长的重要因素。

关键词：中国城镇居民收入消费需求消费者消费水平

退火热处理对Cr_(3)C_(2)-FeCrBSi涂层摩擦磨损性能的影响

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表面技术 2024年第1期53卷 65-77页

作者：姜自滔杨康辛越易新林张世宏王硕煜倪振航安徽工业大学先进金属材料绿色制备与表面技术教育部重点实验室安徽马鞍山243002 安徽马钢表面技术股份有限公司安徽马鞍山243000

目的针对冷轧辊表面的循环应力、摩擦磨损的特殊服役环境,设计空气燃料超音速火焰喷涂(HVAF)制备Cr_(3)C_(2)-FeCrBSi复合涂层来提高工件表面的硬度和耐磨性。方法利用HVAF技术在冷轧辊用合金钢板表面制备不同尺寸陶瓷颗粒混合的Cr_(3... 详细信息

目的针对冷轧辊表面的循环应力、摩擦磨损的特殊服役环境,设计空气燃料超音速火焰喷涂(HVAF)制备Cr_(3)C_(2)-FeCrBSi复合涂层来提高工件表面的硬度和耐磨性。方法利用HVAF技术在冷轧辊用合金钢板表面制备不同尺寸陶瓷颗粒混合的Cr_(3)C_(2)-Fe CrBSi的复合涂层,并在600、700、800℃进行退火处理后得到退火态涂层。利用xRD、SEM、显微硬度计、电子拉伸试验机、盘式摩擦磨损试验机和接触疲劳试验机,考察了不同陶瓷含量和不同退火温度下涂层的相组成、组织结构、机械性能、摩擦磨损性能和接触疲劳失效形式。结果喷涂态涂层的显微硬度、结合强度随着Cr_(3)C_(2)含量的增加先上升后下降。当陶瓷相质量分数为10%时,复合涂层最佳,显微硬度、结合强度分别为459.6HV0.3、42.8 MPa。选取Cr_(3)C_(2)(质量分数10%)-FeCrBSi涂层经过退火处理后,涂层的硬度、断裂韧性、抗磨损性能均有提升,其中摩擦因数由原先的0.89降低至0.80~0.75。此外在700℃下退火3 h得到的涂层,显微硬度可达490.3HV0.3,断裂韧性由2.81 MPa·m1/2提升至3.15 MPa·m1/2,磨损率为6.80×10^(-14) m^(3)/(N·m),与喷涂态涂层相比,磨损率降低了15%。喷涂态、退火态涂层的磨损机制均为磨粒磨损。接触疲劳试验结果表明,退火态复合涂层的接触疲劳失效形式主要有剥落和分层,同时剥落失效情况下涂层的接触疲劳寿命更长,可达2.07×10^(5)转。结论 Cr_(3)C_(2)-Fe Cr BSi复合涂层良好的抗磨损和耐接触疲劳性能主要取决于Cr_(3)C_(2)硬质耐磨颗粒的加入。而退火热处理可以促进涂层向平衡态的转变、同时析出的二次碳化物(Cr, Fe)7C3起到沉淀强化的作用,使得退火态涂层具有更好的抗摩擦磨损性能。

关键词： HVAF 冷轧辊退火摩擦磨损接触疲劳

Achieving work hardening by forming boundaries on the nanoscale in a Ti-based metallic glass matrix composite

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journal of Materials Science & Technology 2020年第15期47卷 192-203页

作者： j.ng Fan Wei Rao junwei Qiao PKLiaw Daniel Sopu Daniel Kiener jürgen Eckert Guozheng kang Yucheng Wu College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan030024China Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of EducationTaiyuan University of TechnologyTaiyuan030024China Key Laboratory of Advanced Technologies of Materials School of Mechanics and EngineeringSouthwest Jiaotong UniversityMinistry of Education of ChinaChengdu610031China Department of Materials Science and Engineering The University of TennesseeKnoxvilleTN37996-2200USA Technische Universitat Darmstadt Institut fiir MaterialwissenschaftFachgebiet MaterialmodellierungOtto-Bemdt-Strasse 3D-64287DarmstadtGermany Erich Schmid Institute of Materials Science Austrian Academy of SciencesJahnstra'e 12A-8700LeobenAustria Department of Materials Science Montanuniversitat LeobenJahnstra'e 12A-8700LeobenAustria

Achieving work hardening in metallic glass matrix composites(MGMCs) is the key to the extensive use of these attractive materials in structural and functional *** this study,we investigated the formation of nanoscale boundaries resulted from the interaction between matrix and dendrites,which favors the work-hardening deformation in an in-situ Ti41Zr32Ni6 Ta7 Be14 MGMC with β-Ti dendrites in a glassy matrix at room *** microstructures of samples after tension were observed by highresolution transmission electron microscopy(HRTEM) and x-ray diffraction(xRD).The work-hardening mechanism of the present composites involves:(1) appearance of dense dislocation walls(DDWs),(2)proliferation of shear bands,(3) fo rmation of boundaries on the nanoscale,and(4) interactions between hard and soft phases.A theoretical model combined with experimental data reveals the deformation mechanisms in the present work,proving that the in-situ dendrites with outstanding hardening ability in the glass matrix can provide the homogeneous deformation under tensile loading at room temperature.

关键词： Metallic glass matrix composites Plastic deformation Work hardening Dense dislocation walls Nanoscale boundaries

Highly stable aqueous rechargeable Zn-ion battery:The synergistic effect between NaV_(6)O_(15) and V_(2)O_(5) in skin-core heterostructured nanowires cathode

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journal of Energy Chemistry 2021年第4期30卷 25-33页

作者： Lanlan Fan Zhenhuan Li Weimin kang Bowen Cheng State Key Laboratory of Separation Membranes and Membrane Processes National Center for International Joint Research on Separation MembranesTiangong UniversityTianjin 300387China School of Materials Science and EngineeringTiangong UniversityTianjin 300387China School of Textiles Tiangong UniversityTianjin 300387China

The aqueous rechargeable Zn-ion batteries based on the safe,low cost and environmental benignity aqueous electrolytes are one of the most compelling candidates for large scale energy storage ***,pursuing suitable insertion materials may be a great challenge due to the strong electrostatic interaction between Zn^(^(2+))and cathode ***,a novel NaV_(6)O_(15)/V_(2)O_(5) skin-core heterostructure nanowire is reported via a one-step hydrothermal method and subsequent calcination for high-stable aqueous Zn-ion batteries(ZIBs).The NaV_(6)O_(15)/V_(2)O_(5) cathode delivers high specific capacity of 390 m Ah/g at 0.3 A/g and outstanding cycling stability of 267 m Ah/g at 5 A/g with high capacity retention over 92.3%after 3000 *** superior electrochemical performances are attributed to the synergistic effect of skin-core heterostructured NaV_(6)O_(15)/V_(2)O_(5),in which the sheath of NaV_(6)O_(15) possesses high stability and conductivity,and the V_(2)O_(5) endows high specific ***,the heterojunction structure not only accelerates intercalation kinetics of Zn^(2+)transport but also further consolidates the stability of the layers of V_(2)O_(5) during the cyclic *** work provides a new perspective in developing feasible insertion materials for rechargeable aqueous ZIBs.

关键词： Aqueous zinc ion battery Heterojunction structure High specific capacity Stable long cycle Synergistic effect

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主流马赫数对气膜冷却效率与掺混损失的影响

工程热物理学报 2024年第8期45卷 2403-2413页

作者：康忠李国庆张深王晓东张燕峰卢新根中国科学院工程热物理研究所北京100190 华北电力大学能源动力与机械工程学院北京102206 中国科学院大学航空宇航学院北京100049 轻型涡轮动力全国重点实验室北京100190

本文采用数值模拟的方法,研究了主流马赫数(Ma_(m))对双射流孔与收缩型双射流孔气膜冷却效率与掺混损失的影响机理。结果表明:随着Ma_(m)增大,冷气贴壁性能增强,近气膜孔区域横向平均冷却效率增大。两种气膜孔结构的冷却核心主要是由下... 详细信息

本文采用数值模拟的方法,研究了主流马赫数(Ma_(m))对双射流孔与收缩型双射流孔气膜冷却效率与掺混损失的影响机理。结果表明:随着Ma_(m)增大,冷气贴壁性能增强,近气膜孔区域横向平均冷却效率增大。两种气膜孔结构的冷却核心主要是由下游气膜孔出流的冷气构成,上游气膜孔出流促使下游气膜孔出流贴近壁面,主射流作用形成的反肾型涡对可以促进冷气横向发展。在掺混损失方面,随着Ma_(m)增大,主射流速度、温度差异增大,气膜冷却造成的熵增不断增大,且主射流速度差异引起的熵增主要发生下游气膜孔出口附近,主射流温度差异引起的熵增主要发生在主射流掺混交界面附近。

关键词：气膜冷却冷却效率掺混损失体熵增率流向涡

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高k栅介质的TDDB效应

安徽大学学报（自然科学版） 2024年第5期48卷 52-56页

作者：任康贡佳伟丁俊贤王磊李广安徽大学材料科学与工程学院安徽合肥230601

半导体工艺进入45 nm以后,使用高k栅介质HfO_(2)代替传统的SiO_(2),解决了因栅氧化层变薄而引起的栅极漏电流过大的问题.经时击穿(time dependent dielectric breakdown,简称TDDB)效应的寿命时间是衡量栅氧化层质量的重要因素,然而高k... 详细信息

半导体工艺进入45 nm以后,使用高k栅介质HfO_(2)代替传统的SiO_(2),解决了因栅氧化层变薄而引起的栅极漏电流过大的问题.经时击穿(time dependent dielectric breakdown,简称TDDB)效应的寿命时间是衡量栅氧化层质量的重要因素,然而高k栅介质存在更多的氧相关缺陷,对电压的反应更敏感,因此研究高k栅介质TDDB效应具有重要意义.研究影响高k栅介质TDDB效应的因素、减轻高k栅介质TDDB效应的途径.研究结果表明:栅氧化层面积越大,越容易被击穿,TDDB效应越严重;温度越高,击穿时间越短,TDDB效应越严重;氧环境下对高k栅介质进行沉积后退火,可减轻高k栅介质的TDDB效应.

关键词：高k 栅介质经时击穿效应栅氧化层 HfO_(2)

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THE FRACTURE CHARACTERISTICS OF δ-Al_2O_3/AlALLOY COMPOSITES

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Acta Metallurgica Sinica(English Letters) 1999年第6期12卷 0-0,0-0+0-0+0页

作者： G.Z. kang Q. Gao C. Yang and j.x. Zhang (Department of Applied Mechanics and Engineering, Southwest jiaotong University, Chengdu 610031, China )

The initial location of the crack and the controlling factor of the fracture in the squeeze casting composites δ-Al2 O3/Al-5.5Zn, δ-Al2 O3/Al-5.5Mg and δ-Al2 O3/Al-cSi were studied by microscopic observation and finite element analysis(FEA). The in situ failure processes were obseroed bU the scanning electronic microscope mp. The distributions of stress components along the fiber length in matta, and the tnean axial stresses of fiber and matrix were calculated by three-dimensional elasto-plastic *** is found that the failure modes of short fiber reiwtreed metal matrix composites change with the variations of the micro-structurnl characteristics of composites, such as fiber orientation, matrix strength and intedecial bonding, etc.

关键词： metal matrix composite short fiber fracture characteristics finite element analysis

Integrated and Seamless Services for Active Aging, a Model for Zhuhai

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journal of Biosciences and Medicines 2014年第6期2卷 41-46页

作者： H. C. j. Wong Y. F. ng x. L. Yuan Beij.ng Normal University - Hong Kong Baptist University United International College Zhuhai China

The Aging Tsunami as it is often quoted to describe the worrying situations of rapidly aging in China has not met with detail planning in facilities upgrade and careful consideration in service models. Broad brushed central policies categorizes services into home care, community care and institutional care and set policy goals at 90-6-4, representing the percentage of older people in receiving respective care. This leaves local officials helpless on how these ideals can be actualized. Some cities have inclined to build huge older people homes and pour resources into institutional care, forgetting the need for older people to be connected with the society. This paper reviews the historical developments of older people services in Hong Kong and recommends an integrative model of social work services connecting institutional, community and home care into a seamless network. The city of Zhuhai will be presented as a perfect experimental city on how its existing facilities can be converted and developed according to the model. Survey on the situations of the 16 public older people homes will be used to illustrate the potentials of an integrative model.

关键词： Integrated Care Active Aging Seamless Care Social Innovations

Discussion　on　the　Network　Method　for　Calculating　Radiant　Interchange　Within　an　Enclosure

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journal of Thermal Science 1994年第2期3卷 130-135页

作者： H.j. kang W.Q. Tao(School of Energy and Power Engineering, xi’an jiaotong University, xi’an, Shaanxi 710049, China) School of Energy and Power Engineering Xi’an Jiaotong University Xi’an China

In this paper the △- Y transformation of a linear electric circuit is introduced to simplify the computation of net radiant heat exchange on a surface of an enclosure with three surfaces. The illustration of the transformation is given by solving six problems taken from the textbooks. Some discussion concerning the possibility of extending the transformation method to enclosures with more than three surfaces, and the condition for applying the network method are also presented.

关键词： radiative heat transfer network method enclosure.