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991.
Giuseppe Di Maio Enrico Meccariello Somashekhar A. Naimpally 《Mediterranean Journal of Mathematics》2006,3(2):189-204
In this paper we use Bartle’s technique to study duality between a topological space and a function space. Normally such a
duality forms an essential part of Functional Analysis. We introduce several new topologies such as the topology of even convergence Te, the closed-cocompact topology Tk ′, the (strong) local proximal convergence.
We explore the topological groups of self-homeomorphisms of a topological space and shed light on the earlier work of Arens,
Dieudonné, Di Concilio. We also study the concepts such as evenly equidistant, functionally equicontinuous, due to Bouziad-Troallic
and topologically equicontinuous due to Royden.
In memory of Professor Enrico Meccariello who made a considerable contribution to this work and who suddenly passed away before
his time 相似文献
992.
The B-spline density-functional method has been applied to the conformers of the (1R, 2R)-1,2-dibromo-1,2-dichloro-1,2-difluoroethane molecule. The cross section, asymmetry, and dichroic parameters relative to core and valence orbitals, which do not change their nature along the conformational curve, have been systematically studied. While the cross section and the asymmetry parameter are weakly affected, the dichroic parameter appears to be rather sensitive to the particular conformer of the molecule, suggesting that this dynamical property could be a useful tool for conformational analysis. The computational method has also been applied to methyl rotation in methyloxirane. Unexpected and dramatic sensitivity of the dichroic-parameter profile to the methyl rotation, both in the core and valence states, has been found. Boltzmann averaging over the conformers reproduces quite closely the profiles previously obtained for the minimum-energy conformation, which is in good agreement with the experimental results. 相似文献
993.
Ying‐Tong Di Ling‐Li Liu Chun‐Shun Li Yu Zhang Qiang Zhang Shu‐Zhen Mu Qian‐Yun Sun Fu‐Mei Yang Hai‐Yang Liu Xiao‐Jiang Hao 《Helvetica chimica acta》2008,91(5):838-843
Eight C30 Daphniphyllum alkaloids, including two new ones, yunnandaphninines F and G ( 1 and 2 , resp.), were isolated from the leaves and stems of Daphniphyllum yunnanense. Their structures were elucidated on the basis of the spectroscopic data. 相似文献
994.
Daniel A. Krzyzanowski Socrates Kypreos Leonardo Barreto 《Computational Management Science》2008,5(3):207-231
Steadily growing prices of oil and emissions coming from conventional vehicles, might force a switch to an alternative and
less polluting fuel in the coming future. In this article we analyze the potential influence of selected factors for successful
market penetration of hydrogen fuel cell vehicles in hydrogen based private transportation economy. Using a world scale, full
energy system, bottom-up, optimization model (Global MARKAL Model—GMM) we address the possibility of supporting the fuel cell
vehicle technology to become competitive in the markets. In a series of optimizations we evaluate the potential influence
of governmental supports and the internalization of externalities related to CO2 and local pollution emissions originating from the transportation sector, as well as preferential crediting options and demonstration
projects promoting fuel cell vehicles. The results suggest that the crucial element is the price of fuel cells and their further
potential to reduce costs. This reduction of costs may be triggered by governmental support such as direct subsidies to fuel
cells, preferential crediting options for the buildup of hydrogen infrastructure as well as penalization of emitters of CO2 and/or local pollutants. 相似文献
995.
Inclusive sum rules for non-abelian symmetry generators and in particular for isospin are studied. A compact formalism is introduced which allows to exaract in a simple way all the consequences of invaraince properties. 相似文献
996.
A kinetic study of isothermal step annealing of neutron-irradiated sodium nitroprusside has been performed. The influence of water and -irradiation on the behaviour of the compound is analyzed and compared with previous results obtained with the analogous compound Na2/Fe/CN/5NO/.2H2O. It is possible to characterize two different fundamental processes that, in spite of occurring at two different temperatures, present the same activation energy than the hydrated system. 相似文献
997.
Roberto Rossi Andrea Marchi Adriano Duatti Luciano Magon Plinio Di Bernardo 《Transition Metal Chemistry》1985,10(4):151-153
Summary The rhenium(V) imido-complexes [Re(NR)Cl3(PPh3)2] have been obtained by heating the rhenium(V) derivative [ReOCl3(PPh3)2] with RNHCHNR R = Ph (1a), p-MeC6H4 (1b), p-ClC6H4 (1c) andp-FC6H4 (1d) in THF under reflux. [Re(NR)Cl3(PPh3)2] (R =p-MeQ6H4) has also been obtained by heating the rhenium(III)-triazenido complex [ReCl2(RN
N
NR)(PPh3)2] in CCl4 under reflux. 相似文献
998.
999.
The stereoisomeric equilibrium composition over Pd/C at high temperature of a series of tetracyclic saturated hydrocarbons having general formula C18H30 was determined by gas chromatography and compared with that calculated on the basis of conformational analysis. Several stereoisomers were isolated. Their 13C NMR spectra agree very well with those calculated according to standard procedures. This method of structural determination was applied to perhydronaphthacene, perhydrobenzo(a)anthracene, 2- and 5-methylper-hydrobenzo (d,e)anthracene and 2,7-dimethylperhydropyrene. 相似文献
1000.
An automatic mass spectrometric method for the quantitation of N-acetylcysteine (NAC) in human plasma has been developed. NAC was extracted from plasma with ethyl acetate and derivatized in two steps with 2-propanol and pentafluoropropionic anhydride. The volatile derivative obtained was ideal for gas chromatographic-mass spectrometric analysis. Data obtained by analysing the plasma of healthy volunteers to whom 600 mg of NAC had been orally given are reported. 相似文献