测量物体表面温度的辐射学方法

本文介绍了辐射学高温测量技术中的多光谱法的原理和计算方法,只要保证精确测量每一波长的表面辐射亮度,用这种方法就可以准确获知物体表面的真实温度和它的视在光谱发射率。本文也评述了经典的亮温法、比色法,给出了保持其优点并提高其测量精度的途径。     

Interaction of tryptophan and phenylalanine with metal ferrocyanides and its relevance in chemical evolution

The interaction of two naturally occurring aromatic alpha-amino acids, namely, tryptophan and phenylalanine, with zinc, nickel, cobalt, and copper ferrocyanides has been studied. Both amino acids showed a high adsorption affinity toward metal ferrocyanides at neutral pH (7.0). Adsorption trends followed the Langmuir adsorption isotherm. Values of the Langmuir constants K(L) and X(m) suggest tryptophan is a better adsorbate than phenylalanine. Zinc ferrocyanide showed the highest adsorption, while the minimum adsorption was found in the case of copper ferrocyanide. Infrared spectral studies of adsorbate, adsorbent, and adsorption adducts indicate that adsorption occurs because of the interaction of adsorbate molecules with outer divalent metal ions present in the lattice of metal ferrocyanides. The present investigation supports the hypothesis that metal ferrocyanides might have concentrated the biomonomers on their surface in primeval seas during the course of chemical evolution.     

On the stabilization of ribose by silicate minerals

The RNA-world theory hypothesizes that early Earth life was based on the RNA molecule. However, the notion that ribose, the sugar in RNA, is unstable still casts a serious doubt over this theory. Recently, it has been found that the silicate-mediated formose reaction facilitates the stabilization of ribose. Using accurate quantum chemical calculations, we determined the relative stability of the silicate complexes of arabinose, lyxose, ribose, and xylose with the intent to determine which would form predominantly from a formose-like reaction. Five stereoisomers were investigated for each complex. The stereoisomers of 2:1 ribose-silicate are the more stable ones, to the extent that the least stable of these is even more stable than the most stable stereoisomer of the other 2:1 sugar-silicate complexes. Thus, thermodynamically, a formose-like reaction in the presence of silicate minerals should preferentially form the silicate complex of ribose over the silicate complex of arabinose, lyxose, and xylose.     

静力压桩施工技术总结

一、工程概况 国航天津分公司飞行部综合楼工程位于天津市东丽区滨海国际机场国航天津分公司飞行部院内，占地5696．75m^2，共分主楼、食堂、室外连廊、动力房等多个子单位工程，建筑面积共计7661m^2，建筑物最大高度17．85m。主楼、食堂、室外连廊为框架结构，动力房为砖混结构。主楼、食堂、室外连廊桩基工程采用静力压桩，     

天津滨海国际机场道面加强工程施工

天津滨海国际机场创建于日伪时期，其前身是天津张贵庄军用机场，一九五二年改建为民用机场，是建国后我国改建的第一个机场，共经过四次较大规模的改扩建。除1996年-1998年，扩建了10万平方米的停机坪，增加一条快速出口滑行道，并对助航灯光、34号跑道仪表着陆系统及配套设施