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151.
ICMS传感器防护技术研究   总被引:1,自引:0,他引:1  
针对ICM传感器安装在飞机内部结构的特征和局部环境特点,提出了应用IMR21纳米复合涂料进行防护的初始方案,并采用加速腐蚀试验方法验证了其耐久性。结果表明,采用IMR21纳米复合保护的传感器安装部位未出现明显的腐蚀失效现象,但传感器引线部位存在一定的原始制造工艺缺陷。在载荷作用下固定传感器引线的硅胶易产生裂纹,致使腐蚀介质易渗入引线焊点处引起焊点腐蚀,导致个别传感器不能正常工作。为此,提出了传感器引线部位细节防腐改进措施,其有效性通过了加速腐蚀试验验证。  相似文献   
152.
航空产品腐蚀损伤当量折算方法研究   总被引:3,自引:2,他引:1  
阐述了航空产品在使用过程中腐蚀损伤的一般规律,综述了腐蚀损伤当量化研究的最新进展,研究了航空金属材料、工艺和结构件腐蚀损伤当量折算方法,并提出了腐蚀损伤当量折算方法的研究发展方向。  相似文献   
153.
为解决中国水环境容量日益稀缺情况下使用权的合理分配问题,在分析了目前现有水环境容量分配模式普遍存在的严重弊端和缺陷,基于产权理论、价值理论和地租理论等,提出了水环境容量分配新模式-租金分配模式,并考虑到各种复杂的影响因素和中国的实际情况,提出了间接确定水环境容量使用租金的综合计算公式。  相似文献   
154.
国内外城市可持续发展指标体系比较   总被引:1,自引:0,他引:1  
文章以英国2009年发表的可持续发展指标体系和美国可持续社区指标指南为例,比较了国内外城市可持续发展评估指标体系,列举了各指标体系的大类和分项,从指标体系的选择和评价方法的确定等方面综述了国内可持续发展指标体系,以期为制定和完善中国的城市可持续发展指标体系提供参考。  相似文献   
155.
冷冻分离法去除水中污染物的对比研究   总被引:1,自引:0,他引:1  
分别以含Ca2+、Mg2+、Na+等无机离子水样和含有溴氨酸(1-氨基-4-溴-蒽醌-2-磺酸钠)的水溶液、UIImann缩合反应产生废水为研究对象,采用静态渐进冷冻法分别在人工条件下进行实验,分析并对比了冷冻法对水体中污染物的去除效果和规律。结果表明:冷冻法可以有效去除水体中各种污染物,由于污染物自身结构不同,冷冻法对污染物分离有选择性,对有机物的去除高于无机离子,对单一污染物去除高于复杂废水。  相似文献   
156.
对在粪大肠菌群实验过程中涉及到的实验室质控设备、培养基、精密度检验等内容进行了分析,并对实验过程中的关键问题进行了阐述。  相似文献   
157.
In-line detonation flame arresters are important safety apparatus to prevent group tank fires caused by the spreading of fire through vapor connection lines. In this study, a DN50 experimental apparatus aimed at the detonation flame penetration characteristics and failure mechanisms in a flame arrester was set up, and a series of experiments were carried out with 6.6% C2H4 and air mixture. Pressure, and velocity of flame penetrating through flame arrester housing and filters were analyzed. Experimental results showed that the attenuation of pressure and velocity was proportional to the thickness of the filters. Two failure modes of the fire-extinguishing process in the flame arrester were captured directly with a high-speed camera. In Mode I, the detonation flame could go straight through the flame arrester filters when the filters were too thin. In Mode II, when the filters were not sufficiently thick, the remained shock wave pressure of detonation flame was still several times of the initial pressure and could rise sharply at the downstream contraction section, resulting in that the flammable gas at the downstream transition section could be compressed and reignited even the flame had been extinguished by filters. These conclusions are helpful to reveal the nature of failure modes of fire-extinguishing process and design flame arresters with high fire-resisting performance by structure improved.  相似文献   
158.
本文构建了公众参与绩效考核指标体系,通过专家咨询法确定各指标权重,然后以湘潭垃圾焚烧发电厂环境影响评价中公众参与为例,运用模糊综合评判法进行实证研究。研究结论对提高环境影响评价中公众参与力度,考核公众参与的绩效水平提供科学依据。  相似文献   
159.
Self‐determination theory suggests that some rewards can undermine autonomous motivation and related positive outcomes. Key to this undermining is the extent to which rewards are perceived as salient in a given situation; when this is the case, individuals tend to attribute their behavior to the incentive, and the intrinsic value of the task is undermined. The role of salience has yet to be explicitly tested with respect to work motivation; we know little about whether undermining occurs in relation to verbal rewards, which characterize everyday work. We examine this in a field‐based quantitative diary study of 58 employees reporting 287 critical incidents of motivated behavior. When considering simple direct effects, the undermining effect was not supported; highly salient verbal rewards associated positively with introjected and external motivation, but at no cost to autonomous motivation. However, moderator analysis found support for the undermining effect for complex tasks; highly salient verbal rewards associated positively with external motivation while associating negatively with intrinsic and identified motivation. The findings suggest that verbal reward salience is an important characteristic of verbal reward perceptions and that salient verbal rewards are not advisable for more complex tasks but can have a valuable motivational impact for simple tasks. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
160.
Functional magnetic resonance imaging (fMRI) is likely to become the major tool for studying the neural underpinnings of organizational behavior. It is a technique for brain imaging that, according to advocates, provides information about which areas of the brain are activated during organizational processes (e.g., leadership and decision‐making). In this article, we take a critical look at this tool from a technical perspective. In particular, we take the reader through the assumptions that must be made at the three main steps of the research process (study design, data capture, and interpretation of results) in order to draw conclusions about organizational phenomena from fMRI research. Applying this analysis to three case studies demonstrates the gap between what fMRI can actually tell us and the claims often made about the contribution of fMRI to understanding and improving organizational behavior. Our discussion provides researchers with a series of recommendations oriented toward optimizing the use of fMRI to help it live up to its potential in the field of organizational behavior and consumers with a means of evaluating fMRI research in order to draw appropriate and warranted conclusions. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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