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排序方式: 共有637条查询结果,搜索用时 293 毫秒
1.
介绍一种基于红外成像技术的金属焊接质量的无损检测方法.首先介绍了检测的基本原理和检测装置,然后详细给出了以边缘检测为基础的缺陷检测方法及检测结果.最后通过比较说明,利用红外成像技术对金属焊接质量进行无损检测是一种很有效的方法. 相似文献
2.
诱导式教学法的运动技能学 总被引:2,自引:0,他引:2
运动技能的学习是体育教学的一个主要目的,体育教学方法的运用是影响运动技能学习的重要因素之一。运动技能学研究表明,诱导式教学法在迁移、练习变化性、反馈和动机等方面对运动技能学习的理论研究和实践探索都具有积极的意义。 相似文献
3.
化学实验教材改革与学生科学素质的培养 总被引:3,自引:0,他引:3
陈志宁 《江西教育学院学报》2006,27(3):74-75
现代化建设的发展依靠人才素质的提高。人才素质的提高依靠教育的改革和发展。化学是一门以实验为基础的自然科学。应根据其特点,积极探讨化学教学中实施素质教育的最佳切入点和结合点,以促进学生素质的全面提高和智慧潜能的充分开发。 相似文献
4.
Tatjana Bayerová 《文物保护研究》2018,63(3):171-188
The technical study of wall paintings from the Buddhist temple complex at Nako, Western Himalayas, was one of the basic preconditions required for designing an appropriate conservation strategy. The complex, composed of four temples from the eleventh–twelfth century, offered a unique possibility to carry out a comprehensive research of technology and painting materials used in early and later western Tibetan Buddhist wall paintings as well as a comparative assessment with murals from other sites in the Western Himalayas. The study was based on extensive fieldwork and an integrated analytical approach comprising a wide range of non-destructive and micro-destructive methods. Answering the question of the coevality of paintings in the smaller temples with other original murals, the precise characterisation of binding media, the detection of the yellow dye gamboge and natural minerals posnjakite and brochantite identified for the first time in Himalayan murals, the clarification of technology of metal decoration, and the making of raised elements are some of the most exciting results which emerged from the research. 相似文献
5.
A multi-analytical approach for the study of brazilwood and its lake pigments was carried out based on historically accurate reconstructions. Recipes for brazilwood lakes from the fifteenth century technical text Livro de como se fazem as cores and the Winsor & Newton nineteenth century colourman's archive were reproduced and compared. Both primary sources allowed for the successful preparation of brazilwood lake pigments with colours that vary from light pink to dark red. The main steps and ingredients for the manufacture of these pigments were common in both sources, particularly the addition of Al3+ in the form of alum, and calcium carbonate (chalk). Reconstructions revealed that the latter acts as a pH buffer and filler, controlling the pH at which the lake pigment precipitates. The main difference between the two sources is that the nineteenth century recipes give the quantities for all ingredients, the precise temperatures and time, and achieved higher relative pigment yields (75% versus 45%). Full chemical characterisation of the reconstructions provided detailed information on the individual steps in the pigment manufacture and revealed that the presence of calcium sulphate dihydrate (gypsum) in the final pigment was a result of its formation in situ. Infrared, reflectance, and fluorescence spectroscopy proved to be essential and complementary techniques: while infrared was used to characterise additives and binders, reflectance and fluorescence data were fundamental for identifying the chromophore. The pigments and paints produced can now be used as standards for the identification and investigation of brazilwood lake pigments found in artworks. 相似文献
6.
李瑞 《广播电视大学学报》2006,(2):99-102
乌兰夫关于党领导内蒙古民族实现区域自治思想主要包括:为什么只有中国共产党才能充当内蒙古民族实现民族区域自治的领导者,中国共产党是怎样领导内蒙古民族实现民族区域自治的,如何保障中国共产党对内蒙古民族实现民族区域自治的领导等内容。 相似文献
7.
在章[1]的基础上,根据M.L.AdenH和M.Merker的复合微粒子光散射理计算了汽溶胶大气中复合微粒子模型的光学特性,得到了汽溶胶的散射截面、吸收截面和消光截面以及红外发射率光谱,为研究大气红外传输提供了计算方法。 相似文献
8.
水杨酸铁的流变相合成和红外光谱 总被引:1,自引:0,他引:1
用流变相反应法合成了水杨酸铁配合物,对样品在4000—400cm^-1。范围内的主要红外光谱吸收峰进行了归属,通过元素分析、TG和IR确定该配合物的组成为Fe(HSal)3.3H2O(HSal=O-OHC6H4CO2)。 相似文献
9.
蔡汉权 《韩山师范学院学报》2005,26(6):72-75
以菊花花瓣为外植体,在无菌条件下诱导愈伤组织,再由愈伤组织进行芽诱导.利用花瓣组织培养易变异的特性,以期培养出新品种.本实验中探讨了6-BA、NAA在诱导愈伤组织和芽诱导中的影响,并获得MS+6-BA2mg/L+NAA0.5mg/L为芽诱导的最佳培养方秦. 相似文献
10.
LU Bao - qi 《上海大学学报(英文版)》2005,9(4):365-368
Infrared (IR) absorption spectra and X-ray powder diffraction (XRD) patterrns of sexpenfine cat's eye from Sichuan Province have been investigated, and infrared absorption bands of the serpentine have been assigned in this paper. The results indicate that the bands near 3 600 - 3 700 cm^-1 belong to the stretching absorption band VOH, the bands in 948 - 1 100 cm^-1 axe assigned to the stretching vibraling band Usvo, and the bands at 600 570 and 440 cm^-1 respectively belong to the bending vibration band VOH, δMg-O and δSi-O. The serpentine cat' s eye includes two types: chrysotile and antigorite. Chrysotile has a sharp and intensive band at 3 688 cm^-1 and a weak band at 3 643 cm^-1 , while antigorite has only one intensive band in the region. At vibration band VSi-O, chrysotile and antigorite have a similar feature at 1 071 cm^-1, but the band at 980 cm^-1 in anfigorite has been split into two bands in chrysotile - a strong one at 1 027 cm^-1 and a weak one at 949 cm^-1. In addition, antigorite has a characteristic bending vibrating band δMg-O at 570 cm^-1. Based on the analysis of the feature of crystal structure, their IR differences axe well explained. 相似文献