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41.
汉画动物图像的艺术特点是极其显明的。既具有较强的写实性特点,又具有突出的意象性特点。另外线条当属动物图像的重要造型符号。线条的表现,有的粗犷有力,有的拙朴率真,有的浪漫舒展,有的自由奔放,有的韵律无限,动人心魄,有的抒情达意,情景交融。为以后中国画的产生发展奠定了坚实的基础。 相似文献
42.
针对动物胶常温凝聚、热硬消耗能源且效率低的问题,以动物骨胶为主要原料,经过碱解、改性处理后得到了一种新型型芯粘结剂,并采用吹CO2气体方式硬化.选择并优化了动物胶碱解工艺,引入活性基团对动物胶进行接枝共聚以及酯化改性,进一步提高了粘结强度,同时对新型动物胶粘结剂的吹气硬化和改性机理进行了理论分析.结果表明:改性动物胶铸造粘结剂最佳配比为m(丙三醇)∶m(糊精)∶m(乙醇)∶m(动物胶)=9∶10∶9∶100,改性温度为75℃,改性时间为90 min.吹CO 2气体硬化的新型改性动物胶粘结剂,初强度大于0.8MPa,终强度达到6.0MPa,能够满足快速制芯生产要求. 相似文献
43.
赵静 《南京工业职业技术学院学报》2012,12(3):16-19
基于中国古代文学作品中经常出现的动物形象狐,探讨了九尾狐在中国文代文学作品中形象的嬗变。狐有九尾,生物发展史上并未出现过,乃是前人的想象。九尾狐由最初的臆想之物到瑞兽,再由天狐到狐妖,其文学形象的改变反映了人们观念的转换,文化的变迁。 相似文献
44.
明清瓷器上的祥禽瑞兽纹饰种类多样、内涵丰富,具有很重要的地位,它们具有丰富的吉祥寓意,反映了当时的时代特色和人们的审美观念。 相似文献
45.
The problem of understanding the transfer of fibres between carding-machine surfaces is addressed by considering the movement of a single fibre in an airflow. The structure of the aerodynamic flow field predicts how and when fibres migrate between the different process surfaces. In the case of a revolving-flats carding machine the theory predicts a “strong” aerodynamic mechanism between taker-in and cylinder and a “weak” mechanism between cylinder and removal cylinder resulting in effective transfer in the first case and a more limited transfer in the second. 相似文献
46.
Conventional creep testing takes a long time to obtain stress-rupture data for aramid fibres at the low stress levels likely to be used in practical applications. However, the rate of creep of aramid can be accelerated by a thermally activated process to obtain the failure of fibres within a few hours. It is possible to obtain creep curves at different temperature levels which can be shifted along the time axis to generate a single curve know as a master curve, from which stress-rupture data can be obtained. This technique is known as the time-temperature superposition principle and will be applied to Kevlar 49 yarns. Important questions relating to the techniques needed to obtain smooth master curves will be discussed, as will the validity the resulting curves and the corresponding stress-rupture lifetime. 相似文献
47.
48.
Pregnancy and lactation involve dramatic changes in behavior and physiology necessary for the successful production and sustenance of offspring. This requires numerous processes to emerge and be coordinated in a finely tuned manner. Reduced corticotropin releasing factor (CRF) receptor activity and hypothalamic-pituitary-adrenal function are thought to be involved in numerous functions during lactation, such as reducing fear and anxiety, which in turn, is proposed to disinhibit aggressive behaviors. K. L. D'Anna, S. A. Stevenson, and S. C. Gammie (2005) reported that central infusion of urocortin 1 and 3, anxiogenic peptides that bind to CRF receptors, reduce maternal aggression in lactating mice and alter neural c-fos expression. However, the relationship between stress hormones and where they act, emotional state, and aggression during lactation is complicated, and our understanding of how these factors influence each other might benefit from a comprehensive reevaluation of these literatures. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
49.
K. Facer† R. Joiner D. Stanton J. Reid‡ R. Hull‡ & D. Kirk§ 《Journal of Computer Assisted Learning》2004,20(6):399-409
This paper reports a study that attempts to explore how using mobile technologies in direct physical interaction with space and with other players can be combined with principles of engagement and self‐motivation to create a powerful and engaging learning experience. We developed a mobile gaming experience designed to encourage the development of children's conceptual understanding of animal behaviour. Ten children (five boys and five girls) aged between 11 and 12 years played and explored the game. The findings from this study offer interesting insights into the extent to which mobile gaming might be employed as a tool for supporting learning. It also highlights a number of major challenges that this format raises for the organisation of learning within schools and the design of such resources. 相似文献
50.
This paper investigates the non-linear elastic behavior of unidirectional and cross-ply CFRP laminates and proposes a new method to measure tensile strain using Lamb waves. Young’s modulus was measured as a function of strain in situ using Lamb wave velocity during a tensile test. The stiffening effect of the carbon fibers on [0]8 specimens and the softening effect of the epoxy matrix on [90]8 specimens were accurately evaluated. Young’s modulus of the 0° ply was obtained as a quadratic function of strain. Using the function and the rule of mixture, the dependence of Young’s modulus on strain was accurately predicted for cross-ply laminates. Based on the results, the tensile strain was quantitatively correlated with the corresponding arrival time of the Lamb waves. The strains obtained from the proposed method agreed well with those from the strain gauge. Finally, the effect of transverse cracks on the in situ Young’s modulus of the cross-ply laminate under a tensile load was investigated. This method clearly detected even a small decrease in the Young’s modulus due to the transverse cracks in stiffening cross-ply laminate. 相似文献