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991.
J. Kozánková S. C. Mojumdar J. Chocholoušek J. Kákoš M. Balog L. Krajčová 《Journal of Thermal Analysis and Calorimetry》2005,81(1):191-196
Summary DúThe aim of this work is to prepare a porous filter composed of two porous layers: macro-porous carrier and micro-porous sodium borosilicate (NBS) glass with TiO2 additive (NBST glass), a Vycor-type glass. In the present work we prepared the macroporous support from the same material (NBST glass) as the upper microporous layer and then by sintering both parts to produce the required composite. This work introduces the results of experiments in the preparation of micro-porous filter on NBST glass base, laid on macro-porous carrier. After sintering of scrap NBST glass, porous samples were prepared to be used as carriers for micro-porous samples of phase-separated NBST glass. In other cases, the following carrier materials were used: a) frita SIMAX, b) Al2O3. The properties of the NBST glass and the changes in the glass structure with temperature were studied in order to determine the optimal sintering temperature of the prepared glasses. For the development of the sintered glasses, valuable information was obtained from heating microscopy (HM) and scanning electron microscopy (SEM) studies. The combination of the HM and SEM results with the measurements of the micro-hardness and density directed to the further study of the phase separated NBST glasses. 相似文献
992.
In this first part a straight general wave-guide with a perfectly conducting outer wall and several dielectrics, excited by an electrically generally polarized matter is considered and the electromagnetic field is determined. 相似文献
993.
Jyoti C. Hegde N. Satheesha Rai Balakrishna Kalluraya 《Journal of Chemical Sciences》2007,119(4):299-302
Novel, convenient and benign synthesis of 2-arylamino-5-(3′-arylsydnone-4-yl)-1,3,4-thiadiazines 3a-l by the interaction of 3-substituted-4-bromoacetyl sydnones 1 with substituted thiosemicarbazides 2 under MW irradiation and solvent-free condition is described. 相似文献
994.
We consider a model describing finitely many free Fermi gas reservoirs coupled by local interactions and prove the Green–Kubo
formulas and the Onsager reciprocity relations for heat and charge fluxes generated by temperature and chemical potential
differentials.
Submitted: September 2, 2006. Accepted: November 21, 2006. 相似文献
995.
We investigate the dynamics of anN-level system linearly coupled to a field of mass-less bosons at positive temperature. Using complex deformation techniques, we develop time-dependent perturbation theory and study spectral properties of the total Hamiltonian. We also calculate the lifetime of resonances to second order in the coupling. 相似文献
996.
The measurement and analysis of broad nuclear magnetic resonance (NMR) spectra of quasicrystals require experimental methods and theoretical interpretations different from NMR investigations of regular periodic crystals. Frequency- and field-sweep methods for recording quasicrystalline NMR spectra are described and compared with the measurement of27Al NMR spectra of icosahedral AlPdMn and decagonal AlNiCo quasicrystals. The nuclear spin interactions that determine the NMR line shape are the same for both types of the above Al-based quasicrystals, where the electric quadrupolar interaction with the broad distribution of its electric field gradient parameters predominantly determines the shape of the broad satellite “background” intensity. The essential observations are an almost isotropic27Al NMR spectrum of the icosahedral quasicrystals and a strong angular dependence of the spectrum of decagonal quasicrystals. 相似文献
997.
Milojković-Opsenica Dusanka M. Lazarević Kristina Ivačković Vojkan Tešić Zivoslav Lj. 《平面色谱法杂志一现代薄层色谱法》2003,16(4):276-279
JPC – Journal of Planar Chromatography – Modern TLC - The chromatographic behavior of nine frequently used water-soluble food dyes has been studied by TLC on RP-18 silica gel.... 相似文献
998.
In this paper, we introduce the notion of Laplacian spectrum of an infinite countable graph in a different way than in the papers by B. Mohar. We prove some basic properties of this type of spectrum. The approach used is in line with our approach to the limiting spectrum of an infinite graph. The technique of the Laplacian spectrum of finite graphs is essential in this approach. 相似文献
999.
In an earlier paper 3 , we studied cycles in graphs that intersect all edge‐cuts of prescribed sizes. Passing to a more general setting, we examine the existence of T‐joins in grafts that intersect all edge‐cuts whose size is in a given set A ?{1,2,3}. In particular, we characterize all the contraction‐minimal grafts admitting no T‐joins that intersect all edge‐cuts of size 1 and 2. We also show that every 3‐edge‐connected graft admits a T‐join intersecting all 3‐edge‐cuts. © 2007 Wiley Periodicals, Inc. J Graph Theory 56: 64–71, 2007 相似文献
1000.
Summary Expanding the range of stationary phases employed in capillary electrochromatography, the development of rigid cellulose-based
micro-beads, their physical-chemical modification and their use in capillary electrochromatography are described. Cellulose-based
stationary phases have been employed in the normal-phase and the reversed-phase modes.
Presented at the 21st ISC held in Stuttgart, Germany, 15th–20th September, 1996 相似文献