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141.
The electron beam process has proved to be an efficient method for the removal of inorganic pollutants from flue gas. Since it simulates natural processes which occur in the atmospheric photochemistry, it appeared attractive to investigate the potential of the e-beam process to clean off-gases which contain hydrocarbon and inorganic trace components. Such emissions arise from industrial processes and from automobile tunnels. Commercial solvents were vaporized in air and irradiated with energetic electrons (300 keV). CO, CO2 and aerosol particles were found as products and were determined quantitatively. The aerosol particles can be collected by a gravel bed filter and can be removed by combustion or biological degradation. From experiments and model calculations it was found that the e-beam process is a very economic tool to remove hydrocarbons from large off-gas volumes at initial concentrations of 50–100 mg C/m3, and that NOx can be removed very efficiently from tunnel off-gas. 相似文献
142.
An efficient angular momentum method is presented and used to derive analytic expressions for the vibration-rotational kinetic energy operator of polyatomic molecules.The vibration-rotational kinetic energy operator is expressed in terms of the total angular momentum operator J,the angular momentum operator J and the momentum operator p conjugate to Z in the molecule-fixed frame Not only the method of derivation is simpler than that in the previous work,but also the expressions ot the kinetic energy operators arc more compact.Particularly,the operator is easily applied to different vibrational or rovibrational problems of the polyatomic molecules by variations of matrix elements Gn of a mass-dependent constant symmetric matrix 相似文献
143.
144.
速差动力学分析及其应用进展 总被引:9,自引:2,他引:9
速差动力学分析是不经分离同时或连续测定混合物中性质密切相关的多组份的重要方法。本文综述了该法在1989-1992年间国内外新进展,尤着重其在有机,生物混合物中多组份分析的应用及新的计算方法,化学计量学的引入。引用最新文献67篇。 相似文献
145.
The polarography of lead ion in dimethyl sulfoxide (DMSO) was investigated in the DMSO concentration range 0–80 vol.%. The complex species identified were Pb2(DMSO)4+3, Pb(DMSO)2+3 and Pb(DMSO)2+6 in [DMSO]<10 vol.%, 10< [DMSO]<43 vol.% and [DMSO]>43 vol.%, respectively. In the presence of pamoic acid, the reduction of lead ion in DMSO was two-electron reversible diffusion-controlled at pH≤6.0, but it became irreversible at pH>6.0. The complex species identified was Pb(Dm)2(Pm)3(OH)6? at pH>6.0. The rate constants of electro-reduction and electro-oxidation, activation energies were determined. The hydrolysis constants of lead ion in dimethyl sulfoxide concentration 40–70 vol.% at pH 4.5–6.0 were found to be of the order of 10?6. The stability constants of the Pb(DMSO)2+3 and Pb(DMSO)2+0 were also determined to be of the orders of 101 and 105, respectively. 相似文献
146.
A model of disordered medium is proposed to describe the monolayer adsorption isotherm on heterogeneous surfaces. The model
is based on the premise that adsorption medium consists of separate regions in each of which there is a permanent local equilibrium
constant, the character of the changes of which is determined by the disorder parameter of the medium.
__________
Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 42, No. 3, pp. 189–193, May–June, 2006. 相似文献
147.
J. Zsakó 《Journal of Thermal Analysis and Calorimetry》1996,46(6):1845-1864
Four many curves methods, viz. calculation techniques based on Eqs (30), (31), (34) and (36), respectively, for deriving kinetic parameters from several TG curves recorded with different heating rates are tested on two sets of theoretical TG curves. The maximum reaction rate temperature and conversion, as well as the approximate formulae used for their calculation are discussed. Some aspects of the kinetic compensation effect are analysed. The final conclusion is that the use of the many curves methods is not reasonable. 相似文献
148.
149.
The relaxation field for solutions of mixed electrolytes of any type is calculated. the calculation is based on the well-known
treatment due to Fuoss-Onsager with the same distance parameter for all the ions in solution. A general conductance-continuity
equation has been established and an improved iterative method of calculation, using Laplace transforms, is proposed. The
relaxation-field results are derived to the second iteration in the perturbation method of integration. 相似文献
150.
Matioli Graciette Zanin Gisella M. De Moraes Flávio F. 《Applied biochemistry and biotechnology》2002,98(1-9):947-961
The influence of substrate or product level on the initial velocity of cyclodextrin (CD) production by cyclodextringlycosyltransferase
from a Brazilian isolate of Bacillus firmus was studied. Our results indicate that the product γ-CD is a stronger inhibitor to the reaction than β-CD. Small saccharides
could also inhibit CD production, although to a lesser extent than the products, and maltose was the strongest inhibitor among
small saccharides. Increasing substrate concentration resulted in greater reduction on enzyme activity for the formation of
β-CD than for γ-CD. We modeled the kinetics of CD production with a set of four reversible reactions including the cyclization/coupling
reaction that forms/opens CDs, and three disproportionation reactions. Our model on the initial velocity data explained well
the substrate inhibition phenomenon. Kinetic parameters were determined by fitting the initial velocity data into our model. 相似文献