排序方式: 共有63条查询结果,搜索用时 15 毫秒
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We have applied new methods for performing coupled-cluster calculations to small molecules containing iodine atoms; specifically, NI3 and N2I4. Because NI3 is known to be very reactive, attempts to measure its thermodynamic properties have been challenging at best. To date, N2I4 has not been isolated, and our results suggest that its isolation will be just as challenging. We find that the ΔHf(NI3)=+307.7 kJ mol−1 and ΔHf(N2I4)=+551.6 kJ mol−1, confirming that they are unstable with respect to their decomposition products N2 and I2. 相似文献
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为了解决视觉测量中图像的实时采集及处理问题,以NI FlexRIO为基础,采用虚拟仪器技术,利用LabVIEW图形化开发平台,并结合相关技术知识,如乒乓操作、流水线技术等,研制了一套图像实时采集及处理系统。该系统并行地实时地实现了图像的采集、存储及处理,在图像分辨率为1 2801 024、采集速率为500 f/s的情况下,系统工作稳定,图像处理速度小于2 ms,并且处理精度达到了亚像素级。该系统对于实现视觉测量的实时性具有重要意义,并且其良好的性能使其在其他相关领域也具有很高的实用价值。 相似文献
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Nilpotents in Armendariz and abelian π-regular rings are multiplicatively closed. However, this fact need not hold in many kinds of rings. This article concerns a class of rings whose nilpotents are closed under multiplication. Rings contained in this class are said to be nilpotent-closed, and the structure of nilpotent-closed rings is investigated in relation with various situations which happen ordinarily in the study of noncommutative ring theory. In the procedure, various sorts of rings are investigated, so that they are nilpotent-closed. We also study familiar conditions under which nilpotents in nilpotent-closed rings form a subring. 相似文献
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GC-MS与正交投影法或渐进窗口正交投影法用于羌活挥发油成分的测定 总被引:5,自引:0,他引:5
中药化学组成的定性定量测定是药物活性理论的基础,联用色谱及其相关的化学计量学方法为中药复杂体系的分离和分辨提供了强有力的工具.采用GC-MS法对传统中药羌活中的挥发油成分进行了分离测定,并对其中重叠色谱峰根据其重叠程度,采用迭代的正交投影法(OPA)和非迭代的渐进窗口正交投影法(EWOP)进行了分辨,得到每个组分的纯色谱和光谱曲线,共分辨出98个色谱峰,通过质谱库检索得到其中65个组分的定性定量结果,占总含量的92.13%. 相似文献
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概述了化学镀镍层中的微量添加剂(PDIS)浓度对化学镀Ni/Pa/Au镀层的析出速度、耐蚀性、焊料湿润性和焊料接合可靠性的影响。 相似文献
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利用虚拟仪器技术完成对整个数控机床群冷却液供给自动控制的工作,解决人工添加冷却液容易过量造成污染环境和降低工作效率的难题.实现根据冷却液液面的上下限进行自动加液,并且使整个控制系统在计算机屏幕上显示和运行参数的设定. 相似文献