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A derivation of an equation which makes it possible to relate the intensities of the absorption bands in the optical spectra of test molecules adsorbed on a surface to the number and energetics of the adsorption sites has been proposed. In the general case, the ratio between the intensities of absorption bands is determined by the energy of the interaction of the adsorbate with the surface sites, the ratio between the numbers of sites, and the oscillator strengths of the optical transitions of the adsorbed molecules. The validity of the equation has been confirmed by analyzing the transmission spectra of p-dimethylaminoazobenzene adsorbed on monosubstituted forms of Glukhov kaolinite containing singly (Na+, H+), doubly (Mg2+), and triply (A13+) charged cations in its exchangeable positions.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 21, No. 4, pp. 475–480, July–August, 1985.  相似文献   
3.
A comparative analysis has been made of the amounts of lipids and their fatty-acid compositions in the seeds of the lines of agenetic collection of cotton plants of the speciesGossypium hirsutum and their hybrids and the variety Tashkent-1. The results obtained on the fatty-acid compositions of some hybrids make it possible to recommend the use of individual lines of cotton plants as donors for improving the food-value indices of cottonseed oil.Institute of Chemsitry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. V. I. Lenin Tashkent State University. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 173–176, March–April, 1991.  相似文献   
4.
The regime of atomization of Si in the presence of Fe-subgroup metals was investigated with the use of a “Saturn” spectrophotometer and a “Graphit-2” electrothermic atomizer. The optimal operating parameters of the atomizer have been determined. It was established that the optimal value of the ashing and the atomization temperatures are, respectively, 900–1000°C and 2400°C, the optimal rate of temperature rise at the stage of atomization is 1400 K/sec, and the appropriate amount of Fe, Co and Ni additions is 1–2 μg. It was established that the formation of gaseous silicides of the Fe-subgroup metals, the dissociation energies of which are lower than the dissociation energies of Si oxides and carbides, increases the sensitivity for determination of Si. To whom correspondences should be addressed. Institute of Single Crystals, National Academy of Sciences of Ukraine, 60, Lenin Ave., Khar'kov, 310001, Ukraine. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 2, pp. 153–157, March–April, 1999.  相似文献   
5.
周代梅  萨本豪  陆中道  蔡勖 《中国物理 C》2002,26(10):1072-1077
用强子–弦级联模型JPCIAE及相应的Monte Carlo事例产生器研究相对论性核–核碰撞中带电粒子多重数的赝快度密度对能量和中心度的依赖关系.无需另调任何模型参数的条件下,此模型可以同时较好地描述相对论性pp实验数据及PHOBOS和PHENIX实验组的Au+Au实验数据.本文指出:因〈Npart〉并非严格定义的物理量,致使实验上和理论上确定〈Npart〉有一定任意性,从而使得每参加者核子对的带电粒子赝快度密度随着〈Npart〉的增加可能逐渐增大,也可能逐渐减小,因此用它来区分粒子产生机制是欠妥的.  相似文献   
6.
Catalytic properties of V-Sb-O systems in acrolein oxidation have been studied. It has been established that the changes in the activity and selectivity of the catalysts are due to the phase and chemical properties of the system.
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7.
Three methods have been developed for the introduction of a β-phenylethylamine fragment into a benzo-crown ether molecule. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 796–800, November–December, 1998.  相似文献   
8.
By taking as an example the obtaining of the spectra of the gas phase over alkali metal iodides and calcium fluoride, we show the possibility of eliminating systematic errors of atomic absorption analysis which are due to nonselective absorption of light. It is been suggested that it makes sense to create a database that would contain molecular absorption spectra of the most abundant substances and would be intended for use by chemistsanalysts.  相似文献   
9.
The main purpose of the NUCLEON experiment is direct measurements of the energy spectra of cosmic rays in the range 1011–1015 eV with the use of the lightweight facility during a prolonged orbital flight. The energy is determined using a technique based on the measurement of the spatial density of secondary particles produced in the initial event of inelastic interaction. The schematic diagram of the NUCLEON facility, the current status of the project, the results of testing the prototype, and plans are presented.  相似文献   
10.
The degradation of Λ transverse polarization produced in S+Pb central collisions at energy 200 GeV per nucleon has been studied in detail. The S+Pb central collision events have been generated using Monte-Carlo generator——LUCIAE at 200 GeV per nucleon. The various factors degrading Λ transverse polarization have been analysed quantitatively. The ratios of Λ′s produced from rescattering, secondary production and decays of Σ, Ξ hyperons to the total measurable Λ′s in experiment have been investigeted and the degradation effect of these Λ on the total polarization has been determined. The simulation and calculation show that above three factors decrease the Λ transverse polarization strongly, however, can not eliminate the polarization completely when the Λ′s are assumed to be produced from hadronic gas in the final state. To explan the experimental data of vanished Λ polarization, it probably needs to consider new mechanisms of Λ production, including a weak effect of QGP formation.  相似文献   
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