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排序方式: 共有442条查询结果,搜索用时 531 毫秒
1.
Summary The gas chromatographic behaviour of crosslinked macroporous 2-hydroxyethyl methacrylate grafted with 2-methyloxazoline was
investigated and the range of applicability of the copolymer was assessed. Retention index values were measured on this copolymer
and compared with those obtained on the terpolymer 2-hydroxyethyl methacrylate-ethylene dimethacrylate-acrylonitrile. Rohrschneider
constants and efficiency data for selected sorbates are given. The use of this type of polymer in the separation of various
types of compounds is documented by various examples. 相似文献
2.
LI Wangliang XING Jianmin XIONG Xiaochao SHAN Guobin & LIU Huizhou . Laboratory of Separation Science Engineering Institute of Process Engineering Chinese Academy of Sciences Beijing China . Graduate School of the Chinese Academy of Sciences Beijing China 《中国科学B辑(英文版)》2005,(6)
More and more stringent regulations of gasoline and diesel oil were proposed with the awareness of environmental protection. Hydrodesulfurization (HDS) is a conventional method to remove sulfur compounds for industrial purpose. The main drawbacks of this … 相似文献
3.
大孔膦酸树脂吸附镧的研究 总被引:3,自引:0,他引:3
本文测定了大孔膦酸树脂对La3 的吸附容量,介质pH、温度、吸附时间等因素对吸附的影响。测得吸附速率常数K298=7.64×10-5S-1,树脂功能基与La3 的络合比为3:1,用化学及红外光谱等方法,得到大孔磷酸树脂吸附La3 的基本参数及其机理。 相似文献
4.
Macroporous poly(methyl methacrylate) produced by phase separation during polymerisation in solution
A. Serrano Aroca M. Monleón Pradas J. L. Gómez Ribelles 《Colloid and polymer science》2007,285(7):753-760
Polymethyl methacrylate (PMMA) sponges were obtained by polymerization in a solution with monomer/ethanol ratios up to 20:80.
The material obtained after the elimination of the solvent present a homogeneous distribution of dispersed pores up to a monomer/ethanol
ratio lower than 40:60. For higher ethanol contents in the reacting mixture, the morphology of the sponge corresponds to a
network of PMMA microparticles, leaving large empty spaces leading to highly porous structure. The monomer/ethanol ratio during
polymerization has a large influence on the porosity, thermal, and mechanical properties of the material and, for large solvent
contents, on the size of the polymer microparticles. 相似文献
5.
In this paper we present a series of work covering a range of aspects relating molecular simulation to experiment. The importance
of surface mediation type effects to the adsorption of simple and complex gases is demonstrated. Coupled with the adsorption
of simple gases is their projection area when used for surface area determination. The pressure dependence of a projection
area is demonstrated for argon at 77 and 87.3 K. A simple model is used to account for the degree of graphitisation of a surface
is demonstrated and used to account for the isosteric heat behaviour of non-graphitised carbon blacks. Turning from surfaces
to porous solids, an alternative treatment of experiment data (either sub or super critical) is presented that avoids the
ambiguity of excess amounts adsorbed. Using this method one is able to obtain pore size distributions and amounts adsorbed
without relying on such things as helium expansion volumes. Since this type of method is usually applied to composite solids
we also demonstrate the correct method for calculating the heat of adsorption using independent sets of simulations. The final
topic covered in this paper is an example of the information that can be gained from the heat capacity of an adsorbed phase. 相似文献
6.
R. Leboda 《Chromatographia》1980,13(9):549-554
Summary The surface properties of complex adsorbents prepared through the pyrolysis of benzyl and n-heptyl alcohols and their mixtures
on the surface of silica gel were investigated. The reactions were carried out in an autoclave at 500°C. A series of adsorbents
having different porous structure, chemical nature of the adsorption centers and their topography were obtained. The best
resolution of different mixtures was obtained by the carbon-silica adsorbent prepared through the pyrolysis of n-heptanol. 相似文献
7.
The adsorption equilibrium isotherms of three aromatic sulfonic acid compounds, 2-naphthalenesulfonic acid, p-toluenesulfonic acid and p-chlorobenzenesulfonic acid, from aqueous solutions by macroporous weak base anion exchanger within the temperature range of 293 K-313 K were obtained. Several isotherm equations were correlated with the equilibrium data, and the experimental data was found to fit the three-parameter Redlich-Peterson equation best within the entire range of concentrations. The study showed that the hydrophobicity of solute has distinct influence on adsorption capacity of the anion exchanger for the aromatic sulfonic acid. Moreover, estimations of the isosteric enthalpy, free energy,and entropy change of adsorption were also reported. The positive isosteric enthalpy and entropy change for adsorption indicate an endothermic and entropy driven process in the present study. 相似文献
8.
通过密度函数理论(DFT-DensityFunctionalTheory)对炭质吸附剂的孔径分布进行了表征。该法以多孔固体上N2吸附分子模型为依据,用一种方法对多孔固体的孔径分布从微孔到大孔范围进行确定。本文用该法对自制的聚丙烯腈活性炭纤维、国产煤质活性炭及日本产活性炭微球等六种炭质吸附剂的孔径分布进行了表征。 相似文献
9.
10.
J. Choma H. Jankowska J. Piotrowska M. Jaroniec 《Monatshefte für Chemie / Chemical Monthly》1987,118(3):315-321
A simple isotherm equation for describing gas adsorption on solids showing heterogeneity of microporous structure is proposed. It is shown that this equation gives a good representation of the experimental data of argon, nitrogen and benzene adsorption on different types of activated carbons. Its parameters may be used to characterize heterogeneity of microporous structure of the solids.
Eine einfache Isotherme zur Beschreibung der Gas-Adsorption an heterogenen mikroporösen Feststoffen
Zusammenfassung Es wird eine einfache Isotherme zur Beschreibung der Gasadsorption an Feststoffen mit heterogener mikroporöser Struktur vorgeschlagen. Es wird gezeigt, daß diese Gleichung die experimentellen Daten für die Adsorption von Argon, Stickstoff und Benzol an verschiedenen Typen von Aktivkohle gut beschreibt. Die Parameter der Isotherme können zur Charakterisierung der Heterogenität der mikroporösen Struktur von Festkörpern herangezogen werden.相似文献