声音感知的语言学探析     

崔雪峰 《沈阳教育学院学报》2010,12(3):55-57,67

按照声音的属性——声音的自然属性和声音的社会属性,将声音划分为自然性声音和社会性声音,并进一步分析了社会性声音的六个主要特征,指出这些特征在声音的感知过程中可以相互联系,相互作用,并且对语言感知的理解及教学实践有一定的启示。  相似文献   

AlN/ZL101原位复合材料的正交实验研究     

田龙  朱艳芳  田青 《安阳工学院学报》2006,(6):8-11

通过正交实验分析,利用气液反应法制备原位AlN/ZL101复合材料并确定了其最佳成分,测试了复合材料的力学性能并对该材料进行了显微金相分析和透射电子显微分析。研究结果表明:AlN/ZL101原位复合材料中原位生成增强体AlN的尺寸为30nm左右,均匀分布于共晶体内部,同基体结合良好;由于细小增强相的作用,热处理后复合材料中的共晶硅以粒状形态均匀分布于基体中。  相似文献   

穴位组织的力学性能及行针过程针体所受阻力分析     

王西明  周永军  张辉 《咸阳师范专科学校学报》2013,(4):21-24

在针刺过程中根据不同区域组织的结构和性质,给出了不同的生物力学模型：表皮无血管无神经,致密而坚硬,可以看作类固体;真皮及皮下结缔组织中血管神经等分布广泛,疏松而柔软。是典型的软物质。从杨氏弹性模量、压缩系数、动摩擦系数等方面对表皮的力学性质进行了研究分析,同时对结缔组织中具有代表性的物质胶原纤维和弹性纤维的力学性质进行了研究分析。结果表明提插法行针主要阻力来自表皮,“得气”后的主要阻力可能来自结缔组织收缩;捻转法行针主要阻力来自胶原纤维和弹性纤维的缠绕。弹性纤维独有的热力学性质在传递针刺能量中可能起着重要作用。  相似文献   

热处理对OCr13Ni5Mo钢组织和性能的影响     

张美丽 《商洛师范专科学校学报》2013,(4):24-26

采用金相观察、冲击、拉伸和硬度测试的方法。研究了二次回火温度对0Cr13Ni5Mo钢显微组织和力学性能的影响。结果表明,不同温度二次回火后。组织以较细的板条状回火马氏体为主;随着二次回火温度的升高,材料的冲击韧性呈上升趋势,强度及硬度近似直线降低。  相似文献   

Advances of physics-based precision modeling and simulation for manufacturing processes     

Gang Wang  Yi-Ming Rong 《上海大学学报(英文版)》2013,(1):75-81

  相似文献   

A nano to macroscale study on structure-mechanics relationships of archaeological oak     

Thomas K. Bader  Karin de Borst  Karin Fackler  Thomas Ters  Susan Braovac 《Journal of Cultural Heritage》2013,14(5):377-388

Mechanical properties of wood at different length scales of its hierarchical structure are governed by structural and compositional properties on smaller length scales. This opens up the possibility to use microstructural data for estimating mechanical properties, which are difficult to assess by conventional, destructive testing but are nevertheless of high relevance for conservation practice. Herein, we investigate such microstructure-mechanics relationships for a particular example, namely the load bearing archaeological oak of the Oseberg Viking ship, displayed at the Viking Ship Museum in Oslo, Norway. In order to identify the effects of degradation on the mechanical behavior and their relations to the microstructure, recent oak specimens of different geographical origin (Norway and Austria) are investigated as well. Wood exhibits a cellular structure. Its cell walls are composed of an amorphous polymer matrix consisting of lignin and hemicelluloses and embedded, stiff cellulose fibers. At the cell level, experimental studies comprised microscopic investigations of the cellular structure, chemical analyses of the composition of the cell walls, as well as nanoindentation tests on single cell walls. The same samples were also analyzed on the macroscopic level, where additionally mass density and annual ring data were measured together with ultrasonic stiffnesses. The chemical data clearly indicate deterioration in the archaeological oak, affecting mainly hemicelluloses and amorphous cellulose. At the cell wall scale, however, this does not necessarily lead to a weaker material behavior. The nanoindentation modulus, as a measure of the cell wall stiffness, was found to even increase. This is counterintuitive to our understanding of the effects of chemical degradation. It might be due to possible modification of lignin in the Oseberg oak, and thus have a stronger effect on the indentation modulus than the concurrent weakening of the interfaces between the load-carrying cellulose fibers and the connecting cell wall matrix when analyzing wood at the microscopic level. A similar effect is also observed for the transversal stiffness of macroscopic samples, which increases. In tension-dominated loading modes, however, the degradation of the interfaces is the dominant effect, resulting for example in a considerable reduction of the macroscopic stiffness in longitudinal direction. This underlines the utmost relevance of the loading condition on the remaining load-carrying capacity of degraded wood. On the macroscale, effects of the geographical origin (i.e. growth conditions) on ring characteristics of the oak tissues override the effects of degradation on the mechanical behavior. They have to be carefully extracted in order to come up with conclusions on the effect of degradation from macroscopic test results. The identified microstructure-mechanics relationships provide the basis for–in further research steps–building mathematical models describing the relations between microstructural characteristics and macroscopic mechanical properties and, thereon, for structural analyses of historical wooden objects.  相似文献   

图像捕获设备测量与分析数字印刷质量的可行性   总被引：4，自引：0，他引：4  

姚海根 《出版与印刷》2008,(3):2-5

本文讨论以图像捕获设备组建数字印刷质量检测与分析系统的可能性。工业界的成功应用经验表明,只要经过了正确的密度标定,则这种系统完全适用于数字印刷质量检验与评价。  相似文献   

试论期刊的特征与作用——兼评当前期刊出版的某些不良现象     

常勤毅 《宁波教育学院学报》2002,4(4):72-75

期刊是一种有固定的出版形式和统一固定名称的连续的定期出版物。而当前有的期刊 ,忽略或无视期刊的独特属性与功能。无论是何种类型的期刊都应该坚持期刊的本质特征与作用 ,自觉抵制、防止和消除不良现象的发生。  相似文献   

M-ZSM-5分子筛的结构及催化性能研究进展   总被引：3，自引：0，他引：3  

薛英  吴宇  万家义 《绵阳师范学院学报》2005,24(5):1-4

探究了ZSM-5分子筛的晶体结构、孔结构及酸性质：对通过离子变换对其表面进行优化以提高催化活性方面的研究工作进行了阐述；对Cu-ZSM-5分子筛上NO直接催化分解反应提出了：4CuO=2Cu20＋02，2Cu2O＋4NO=4CuO＋2N2＋O2的反应机理。  相似文献   

6061-T5铝合金搅拌摩擦焊接头组织和力学性能     

吕煜  郭国林  徐子骞  王杰  王乐  吴柯寒  高安慧 《常熟理工学院学报》2020,(2):66-69

采用搅拌摩擦焊技术对6061-T5铝合金进行焊接,分析了焊接速度对接头成形、微观结构及力学性能的影响.结果表明:随着焊接速度的增加,沉淀相固溶度下降,晶粒细化;焊接速度过大时,热输入不足,呈现原始态组织.当转速为800 r/min,焊接速度为60 mm/min时,接头成形良好,抗拉强度达到最大值.采用合适的搅拌摩擦焊工艺参数,6061-T5铝合金能实现可靠的连接.  相似文献