Synthesis and characterization of flavylium salts having three types color depending on recrystallization conditions

Three types of flavylium salts (FVs, yellow, green and red) have been synthesized and the colors depended on recrystallization conditions. The existence of these color states was confirmed by diffuse reflectance spectra. The spectra were almost the same as the absorption spectra in ethanol solution. The molecular state of FVs in crystals will be the same as that in solutions. The crystal colors of the FVs are controlled by the recrystallization conditions.     

丙三醇在Pt电极上吸附和氧化过程的原位FTIR反射光谱研究

运用电化学循环伏安(CV)和原位FTIR反射光谱方法, 研究了丙三醇在Pt电极上的氧化过程。结果指出, 丙三醇的氧化是一个复杂的表面过程。其间包括脱水、吸附、解离等步骤。根据CV和红外实验数据, 本文提出了Pt电极上丙三醇解离吸附的表面反应机理和不同电位下丙三醇氧化的分子过程。     

用衰减全反射红外二向色性表征聚环氧乙烷薄膜的表面取向

应用衰减全反射二向色性表征聚合物的表面取向,可不必测定样品的折光率使大多数实验简化.以聚环氧乙烷为例.用衰减全反射偏振红外光谱测定了它的表面二向色性比和计算了相应的取向函数.     

Gravitational Waves in Matter

The theory of gravitational waves in matter is given. This covers the questions of constitutive relation, number of independent polarizations, index of refraction, reflection and refraction at an interface, etc. The theory parallels the familiar optics of electromagnetic waves in material media, but there are some striking differences. The use of the Campbell-Morgan formalism in which the gauge-invariant tidal force dyads E and B rather than the gauge-dependent metric perturbations are the unknowns is essential. The main justification of the theory at the moment is as a theoretical exercise worth doing. The assumption: size L of the medium gravitational wave length (infinite medium) rules out application to the already well-understood detection problem, but there may be an application to gravitational wave propagation through molecular gas clouds of galactic or inter-galactic size.     

红外反射吸收光谱法研究金属丝表面的化学反应

本文试用漫反射装置的高效率椭球面镜子来收集金属丝玻璃纤维等表面的反射光谱, 发现当样品轴与光的入射面平行时, 可得到与红外大角度入射装置收集金属板表面的反射吸收光谱相似的效果。用这一方法研究铜丝表面咪唑(C3H4N2)涂层的结构, 发现金属铜与咪唑之间发生了化学反应, 生成Cu(C3H3N2)2m.p. 260-263℃, 本文研究了其反应机理。     

Unequivocal evidence of the presence of titanols in Ti-MCM-48 mesoporous materials. A combined diffuse reflectance UV-Vis-Nir and 29Si-MAS-NMR study

Mesoporous Ti-MCM-48 materials were synthesised with titanium loading varying from 1 to 3 wt% TiO₂. Post-synthesis silylation treatment of the silica surface led to the transformation of silanols, (SiO)₃SiOH, into (SiO)₃SiOSi(CH₃)₃ groups, which were identified by means of ²⁹Si-MAS-NMR and diffuse reflectance (DR) Nir spectroscopy. DR UV-Vis spectroscopy was performed to clarify the nature of Ti(IV) sites present in these samples. The UV-Vis spectra show a band at 210 nm with a shoulder at 230 nm, typically assigned to oxygen to tetrahedral Ti(IV) (LMCT) electronic transitions. Interestingly, the component at 230 nm, which was assigned to an electronic transition that involves titanium sites linked to OH groups (named as titanols), strongly decreased upon the silylation treatment. This is a clear evidence that, beside silanols, also titanols were silylated, leading to (SiO)₃TiOSi(CH₃)₃ sites. This fact can be taken as an unequivocal assignment of the shoulder at 230 nm due to oxygen to tetrahedral Ti(IV) electronic transition related to titanol species.     

铂电极上苯和苯磺酸吸附定向的现场红外反射吸收光谱电化学方法研究

本文用现场红外反射吸收光谱电化学方法和循环伏安法研究铂电析上苯和苯磺酸的吸附定向。对于苯/铂势系, 电势在-0.6至0.0V(相对饱和甘汞电极)内, 苯主要以垂直方式吸附; 在0.0至0.8V内则主要以平躺方式吸附。对于苯磺酸/铂体系,电势在-0.4V至0.0V内, 苯磺酸分子中的苯环主要呈垂直吸附且SO~3H基团远离电极表面; 在0.0至1.0V内则主要以倾斜平躺方式吸附, SO~3H基团通过其中的两个氧原子吸附于电极表面上。     

固相配位化学反应研究XXXIX. 四氰合镍酸钾与固体有机酸在室 温下的固相反应

本文用红外、紫外可见漫反射、X射线粉末衍射和四极质谱等实验手段,研究了四氰合镍酸钾一水合物与草酸、丙二酸、反丁烯二酸、丁二酸、己二酸的固相反应,发现K~2[Ni(CN)~4].H~2O与一些固体酸在室温下就发生反应,生成Ni(CN)~2.xH~2O,并放出HCN气体。由产物与反应物相对含量大小,得到固体有机酸的酸性强弱顺序为:草酸二水合物>丙二酸>反丁烯二酸>丁二酸>己二酸。讨论了可能的反应机制。