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在玻璃衬底上采用RF溅射法制备非晶SiGe薄膜的基础上,采用金属Ni诱导法对所制备的薄膜进行晶化烧结,并以Pt催化氢氧化放热反应和SiGe薄膜的热电势效应为原理制备出了小型热电势氢传感器。测试表明:以500℃烧结所得SiGe薄膜材料为敏感基体,在100℃工作温度下所制备的传感器对3%H2灵敏度为0.7mV,检测的浓度范围大约为0.02%-5%,且输出电压随着烧结温度的升高而升高。 相似文献
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S 波勘探为当今世界所瞩目,纷纷进行试验和研究。P 波和 S 波结合起来可以得到 P 波无法得到的重要的地下信息(孔隙率、孔隙内流体、泊松比等)。S 波勘探中当前最重要的问题是震源。为此,我们研究和生产了 S 波震源,其中效果最好的并能勘探到深部地层的是可控震源。方法是用钉子把铁板固定,在铁板上放置一堆重物,然后以水平方向连续变频震动铁板。因为这种方法会给地面造成损坏,而且难以采用,所以只好采用 P 波可控震源。Edelmann(1981)发明了用二台反相位 P 波可控震源以压制中间的 P 波,从而增强 S 波。这种方法被称为 Shover S 波新产生法。它仍使用原来的 P 波可控震源,但不会给地面带来损坏,可以说是简便的S波产生法。但Edelmann论文中对波干扰的利用和S波的实际地层传播能量讨论的不深刻(Dankbaar,1982).本文在介绍Shover方法的基础上,详细地研究了一台P波可控震源产生的S波,然后对二台反相位可控震源压制中问P波,增强S波的情况作了验证。此外,还研究二台反相位可控震源的VSP勘探。研究结果证明,本方法产生S波的能量可达到深层。 相似文献
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1.序言超高真空密封用的金属空心 O 圈近年来普及很快。因为空心,所以具有压紧力小、弹性大等优点。为提高和凸缘之间的密封性,镀材应比基材的金属软并富有延展性。一般用银作镀材,也可用金、铜、镍、铟等。这些材料对金属空心 O 圈(以下简称 O 圈)的密封特性(压紧力和有效复原量)产生什么影响,在此以前还不十分清楚。为此,对用上述的银、金、铜、镍、铟作镀材的 O 圈作压缩泄漏试验并研究它对密封特性的影响。O 圈的截面直径有:0.9mm,1.6mm,2.4mm,3.2mm。这里报告的是最后三种直径的 O 圈的试验结果。 相似文献
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数据显示控制系统用来控制若干刷新存储器中有关数据的显示,刷新存储器在多种显示器中,包括在图象选择显示器、图象叠加显示器和图象位移显示器中都是很实用的。刷新存储器中的每个数据包含一显示控制位,这些位可确定是否在显示屏上显示数据。数据显示控制系统从各刷新存储器读出一数据信息以作图象显示,并仅在此数据信息中的一显示控制位的内容显示在显示器上时,该系统才包含将此数据信息转换成图象显示器的一个视频信号。对每个数据来说,显示控制位的内容是可变的。 相似文献
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Local spatial interaction between neighborhood land-use categories (i.e.neighborhood interaction) is an important factor which affects urban land-use change patterns.Therefore, it is a key component in cellular automata (CA)-based urban geosimulation models towards the simulation and forecast of urban land-use changes. Purpose of this paper is to interpret the similarities and differences of the characteristics of neighborhood interaction in urban land-use changes of different metropolitan areas in Japan for providing empirical materials to understand the mechanism of urban land-use changes and construct urban geosimulation models. Characteristics of neighborhood interaction in urban land-use changes of three metropolitan areas in Japan, i.e. Tokyo, Osaka, and Nagoya, were compared using such aids as the neighborhood interaction model and similarity measure function. As a result,urban land-use in the three metropolitan areas was found to have had similar structure and patterns during the study period. Characteristics of neighborhood interaction in urban land-use changes are quite different from land-use categories, meaning that the mechanism of urban land-use changes comparatively differs among land-use categories. Characteristics of neighborhood interaction reveal the effect of spatial autocorrelation in the spatial process of urban land-use changes in the three metropolitan areas, which correspond with the characteristics of agglomeration of urban land-use allocation in Japan. Neighborhood interaction amidst urban land-use changes between the three metropolitan areas generally showed similar characteristics. The regressed neighborhood interaction coefficients in the models may represent the general characteristics of neighborhood effect on urban land-use changes in the cities of Japan. The results provide very significant materials for exploring the mechanism of urban land-use changes and the construction of universal urban geosimulation models which may be applied to any city in Japan. 相似文献