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131.
聚丙烯颗粒在水溶液中与丙烯腈和二乙烯基苯反应,得接枝交联产物(Ⅰ)。Ⅰ被氨肟化再经成笼反应.得笼形聚偕氨肟树脂(Ⅱ)。笼内仅吸留易于除去的溶剂丙酮。若Ⅰ成笼后再氨肟化,所得吸收剂(Ⅲ)将吸留大量的羟胺,它缓慢地释放出来,干扰吸收剂对酸、碱离子或分子吸附容量的测定。Ⅱ对一些离子例如Hg2+和MnO4-的吸附能力与Ⅲ不同,被认为是两者的网络结构不同所致。 相似文献
132.
133.
The change in semiconductive properties of β-apo-8′-carotenal, astacene and methyl bixin on adsorption of various vapours
on the crystallite surfaces has been studied at a constant sample temperature. The adsorption of vapours enhances the semiconductivity
of the polyenes appreciably. This enhancement depends on the chemical nature and also on the pressure of the adsorbed vapour.
The adsorption and desorption kinetics follow the modified Roginsky-Zeldovich relation. A two stage desorption process, the
first stage of which gives a Lennard-Jones potential energy curve and is followed by a rate-determining transition over a
potential energy barrier to the second stage of adsorption forming weakly bound complexes between the vapour molecules and
the polyene crystallites, can explain satisfactorily the experimentally observed kinetic data. 相似文献
134.
Various methods for the preparation of metal oxide catalysts for environmental control purposes are described. These include coprecipitation, sol-gel, and impregnation, and are used to prepare mixed oxide catalysts of the types SnO2-MO2 (M=Ce or Zr), SnO2-Ln2O3 (Ln = lanthanide), Ln-doped CeO2, Cr (VI)-doped SnO2, and Cu(II)-doped SnO2. The aggregation in stable colloidal sols of SnO2, CeO2 and ZrO2 is dependent on the concentration of the metal oxide. Techniques for the characterisation of these catalyst materials include gas adsorption, X-ray diffraction, and TEM/EDXA. 相似文献
135.
136.
E. Miyoshi T. Iura Y. Sakai H. Tochihara S. Tanaka H. Mori 《Journal of Molecular Structure》2003,630(1-3):225-232
We investigated the interactions between the Si(111) surface and the Na, Mg, and Al atoms using cluster model calculations. Calculations were performed at levels of complete-active-space self-consistent-field (CASSCF) and multi-reference singly and doubly excited configuration interaction (MRSDCI) calculations using the model core potential method. Our calculations revealed that the most favorable sites of Na, Mg, and Al adsorption on Si(111) are on top (T1), bridge (B2), and 3-fold filled (T4) sites, respectively. The nature of chemical bonds between these metal atoms and the dangling bonds of the surface Si atoms are found to be essentially covalent. 相似文献
137.
138.
Estimation of micropore size distribution in active carbons from adsorption isotherms of water vapor
A possibility of estimation of the micropore size distribution in the carbon adsorbents with the developed micro-and mesoporous
structure by analysis of the adsorption isotherms of water vapors was considered. At saturation water condenses in micropores
in a form of a weakly compressed liquid. However, water molecules in micropores are packed not so closely as in the liquid
because of steric hindrance. Therefore, the real density of water adsorbed in the micropores is lower than that of water adsorbed
on an open surface and lower than the density of the normal liquid. An analysis of the adsorption isotherms of water vapors
with account for the both opposite effects on the water density gives reliable data on the micropore sizes of the carbon adsorbents.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 40–43, January, 2007. 相似文献
139.
In this paper the equation for thin-layer adsorption chromatography with multicomponent mobile phases, proposed by O?cik in 1965 is extended to energetically heterogeneous solid surfaces. Other forms of this equation, more convenient in practical applications, are presented. Model calculations are made for TLC with binary mobile phases according to the modified form of O?cik's equation. Finally, this equation is compared with that of Snyder. 相似文献
140.
H2PtCl6可被一系列的酸处理定形聚偕胺肟树脂所吸附,吸附容量的大小与处理树脂的质子酸的Pka值有关.认为是解高度低的酸所处理的树脂上的伯胺基成盐的机会较少,即树脂的吸附中心保留着较多的空穴,有利于H2PtCl6的接近而被吸附下来.吸附动力学的研究表明化学反应是吸附速度的控制因素。 相似文献