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991.
Various kinds of semicontinuity and the solution sets of parametric multivalued symmetric vector quasiequilibrium problems 总被引:2,自引:1,他引:1
We introduce some definitions related to semicontinuity of multivalued mappings and discuss various kinds of semicontinuity-related
properties. Sufficient conditions for the solution sets of parametric multivalued symmetric vector quasiequilibrium problems
to have these properties are established. Comparisons of the solution sets of our two problems are also provided. As an example
of applications of our main results, the mentioned semicontinuity-related properties of the solution sets to a lower and upper
bounded quasiequilibrium problem are obtained as consequences. 相似文献
992.
In this paper we propose a cross-validation selection criterion to determine asymptotically the correct model among the family of all possible partially linear models when the underlying model is a partially linear model. We establish the asymptotic consistency of the criterion. In addition, the criterion is illustrated using two real sets of data. 相似文献
993.
The applicability of methods of molecular electro-optics for the study of colloid systems is analyzed. It is shown that the basic formulas of molecular electro-optics can be applied for the calculation of electrical and geometric characteristics of particles of colloid size. The basic integral equations describing electro-optical effects in colloid systems are presented to find distributions of particles over their size and polarizability anisotropy. The accuracy of their solutions is evaluated by mathematical simulation. Studying the dichroism induced by an external electric field in aqueous colloids of anisylidenbenzidine and graphite, the polarizability and size distribution functions are found for particles with an “optical weight.” From the resulting distribution functions, the statistical dependences of the polarizability anisotropy of those particles on their size are found and analyzed. 相似文献
994.
Susanne Voß Vadim Nigmatoulline Marjan Bele Stane Pejovnik Jürgen O. Besenhard 《Monatshefte für Chemie / Chemical Monthly》2001,132(4):487-497
Summary. A widely applicable aqueous dip-coating process termed substrate induced coagulation (SIC) suitable for coating various types
of substrates (e.g. polar and unpolar polymers, inorganic glasses, metals) with fine particulate materials (e.g. carbon blacks, small particle size SiO2 or TiO2) has been developed. This process is based on the interaction of a conditioner (water soluble polymers or polyelectrolytes,
e.g. proteins, polyvinylalcohols, polyacrylates with low charge density) which is adsorbed on the substrate with a surfactant-stabilized
dispersion containing some additional electrolyte. Employing dispersions of conductive particles, the resulting coatings can
be used as a conductive starting layer for electroplating. Such layers are fairly rinse-proof and may be applied in the metallization
process of through holes in printed wiring boards or for the production of highly conductive composite materials from coated
particles. SIC has also been used to improve the distribution of carbon in composite battery electrodes such as MnO2/C.
Received August 24, 2000. Accepted September 19, 2000 相似文献
995.
Pham N. Khanh Cam-Tu D. Phan Dai Q. Ho Quan Van Vo Vu T. Ngan Minh Tho Nguyen Nguyen T. Trung 《Journal of computational chemistry》2019,40(2):464-474
Interactions of dimethyl sulfoxide with carbon dioxide and water molecules which induce 18 significantly stable complexes are thoroughly investigated. An addition of CO2 or H2O molecules into the DMSO⋯1CO2 and DMSO⋯1H2O systems leads to an increase in the stability of the resulting complexes, in which it is larger for a H2O addition than a CO2. The overall stabilization energy of the DMSO⋯1,2CO2 is mainly contributed by the S=O⋯C Lewis acid–base interaction, whereas the O − H⋯O hydrogen bond plays a significant role in stabilizing complexes of DMSO⋯1,2H2O and DMSO⋯1CO2⋯1H2O. Remarkably, the complexes of DMSO⋯2H2O are found to be more stable than DMSO⋯1CO2⋯1H2O and DMSO⋯2CO2. The level of the cooperativity of multiple interactions in ternary complexes tends to decrease in going from DMSO⋯2H2O to DMSO⋯1CO2⋯1H2O and finally to DMSO⋯2CO2. It is generally found that the red shift of the O − H bond involved in an O − H⋯O hydrogen bond increases while the blue shift of a C − H bond in a C − H⋯O hydrogen bond decreases when a cooperative effect occurs in ternary complexes as compared to those of the corresponding binary complexes. © 2018 Wiley Periodicals, Inc. 相似文献
996.
Tran Thi Ngoc Doan Chien Thang Nguyen Van Bon Nguyen Anh Dzung Wang San-Lang 《Research on Chemical Intermediates》2019,45(2):727-742
Research on Chemical Intermediates - Microbial chitinase has received great attention due to its medical, biological, and agricultural applications. In this study, over 50 bacterial strains were... 相似文献
997.
Sha Zhu Anh Tuan Tran Yuki Hirokami Geoffrey Gontard Omar Khaled Yongmin Zhang 《Journal of carbohydrate chemistry》2019,38(2):139-149
While an epoxide on a sugar-derived aziridine studying was opened, an unexpected formation of bicyclic compounds was observed. The structure of these bicycles depended on the nature of the protecting group on the nitrogen atom of the aziridine. These compounds appeared to be weak glycosidase inhibitors. 相似文献
998.
We present a comparative study of the control of-group velocity in three-level atomic systems including $\Lambda{}$-, Ladder-, and-V-types via spontaneously generated coherence (SGC) and relative phase of laser-fields. In the steady regime, expressions of group index are derived as an-analytical function of controllable parameters related to SGC and relative phase.-It is shown that the group velocity can be further slowed down or speeded up-under SGC in which modifications of group velocity due to the SGC in $\Lambda{}$--and V-systems are stronger than that in Ladder-system. In particular, when-interference strength of SGC p increases from 0.7 to 1.0, the light-propagation is switched from superluminal to subluminal modes (for $\Lambda{}$--and Ladder-systems) or from subluminal to superluminal modes (for V-system). In-the presence of relative phase, the group velocity changes between subluminal and-superluminal modes with a period of 2$\pi{}$. In resonant region, the largest-positive value of group index reaches at the relative phase $\varphi{}$ = $\pi{}$-while the largest negative value of group index reaches at $\varphi{}$ = 0 and-2$\pi{}$ for the $\Lambda{}$- and Ladder-systems, otherwise, for the V-system the-largest positive group index occurs at $\varphi{}$ = 0 and 2$\pi{}$, and the largest-negative group index occurs at $\varphi{}$ = $\pi{}$. 相似文献
999.
Tri Tuan Nguyen Tran Thanh Tung Dusan Losic Luu Thi Lan Anh Le Hong Phuc Xuan Sang Nguyen 《Current Applied Physics》2019,19(10):1082-1087
One of the most studied photoluminescence emission peaks of anatase titanium dioxide (TiO2) is green, located at about 520 nm, which is assigned to the radiative recombination between a mobile electron in the conduction band and oxygen vacancy defect as a trapped hole in the bandgap. Composite materials of TiO2 with graphene are normally shown by the gradual quenching of photoluminescence intensity as a result of carrier lifetime extension, which is important to enhance photocatalytic activity. Herein we report an observation of the intensity enhancement of the green PL emission in a composite TiO2 nanotube (TNT) and graphene produced through facile hydrothermal synthesis. The heterojunction formation of graphene and TNT makes the excited photoelectrons easy to diffuse from TNT to graphene. Hence, the recombination rate of mobile electrons in graphene and trapped holes located on the nanotube surface is enhanced due to the high mobility of electrons in graphene. 相似文献
1000.
The context of present work is related to the study of strongly nonlinear absorbers (NESs) aimed to attenuate vibrations induced in a single degree-of-freedom oscillator and working under the principle of targeted energy transfer (TET). The purpose motivated by practical considerations is here to establish a design criterion permitting to first ensure whether NES absorber is active or not and second to provide a nonlinear stiffness lower bound for optimal energy absorption during pumping phases. An asymptotic expansion of dynamic equations of motion under transient regime enables to emphasize a new definition of activation energy and to investigate the influence of damping upon the efficiency of one-way channeled energy transfer. Methodology is straightforwardly extended to the case of multiple NES attached in parallel to the primary oscillator. Numerical benchmark simulations corroborate the reliability and robustness of proposed design procedure. 相似文献