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141.
Editoral Board     
《Polyhedron》2003,22(14-17):IFC
  相似文献   
142.
The aim of this article is to investigate the local convergence analysis of the multi-step Homeier-like approach in order to approximate the solution of nonlinear equations in Banach spaces, which fulfilled the Lipschitz as well as Hölder continuity condition. The Hölder condition is more relax than Lipschitz condition. Also, the existence and uniqueness theorem has been derived and found their error bounds. Numerical examples are available to appear the importance of theoretical discussions.  相似文献   
143.
ROXMAS (ROx Chemical Conversion/CIMS), a novel method for atmospheric speciated measurements of HO2 and the sum of organic peroxy radicals (∑RO2) developed by MPI-K, has been successfully deployed in a field campaign on Monte Cimone, Italy, June-July 2000. The method relies on amplifying chemical conversion of peroxy radicals to gaseous sulfuric acid via the chain reaction with NO and SO2 and detection of the sulfuric acid by CIMS. Speciated measurements have been realized by diluting atmospheric air in either N2 or O2 buffer, thus exploiting the dependence of the conversion efficiency of RO2 to HO2 on [O2], [NO], and [SO2]. Speciated measurements of HO2 and RO2 are required to provide further insight into radical partitioning and thus to elucidate further the mechanisms of the oxidation of volatile organic compounds in the troposphere. This methodology yields useful speciated results for atmospheric conditions where CH3O2 makes a major contribution to total RO2. Under other conditions it gives an upper limit for [HO2] and a lower limit for [∑RO2].  相似文献   
144.
A study of the experimental results on the plasma emissions of water and ethanol vapor samples, induced by Nd:YAG laser in ambient helium and nitrogen gases at atmospheric pressure, is presented here. The result reveals distinct geometrical and spectral characteristics of the plasma emissions generated in the helium gas when compared to those observed from nitrogen gas plasma. Most remarkable is the narrow line width and low continuum background exhibited by emission lines of the analyte atoms from helium plasma, including the hydrogen emission line which is known to suffer from notorious broadening effects in conventional laser induced breakdown spectroscopy (LIBS). It is further shown on the basis of the measured spatial distributions and time profiles of the emission intensities, that the excellent spectral quality is attained by taking advantage of the meta-stable excited state of helium atoms for the delayed excitation of the hydrogen and other analyte atoms, this allows the detection of those atomic emissions to be performed under more favorable conditions. The result of this study has thus demonstrated the feasibility of achieving high-quality spectrochemical analysis, including hydrogen analysis with laser-induced helium gas breakdown spectroscopy. PACS 52.38.Mf  相似文献   
145.
On the basis of crossing symmetry a new set of exact relations involving theππ partial wave amplitudes have been derived, using Roskies’ amplitudes.  相似文献   
146.
Infrared spectra and normal vibrations of ions of the type and , with X and Y as S, O and N have been compared and discussed.  相似文献   
147.
The paper presents a simple numerical model able to provide directly kinetic constants and reliable numerical rheometer curves for S-TBBS-DPG natural rubber. The approach is suitable to calculate the kinetic constants and maximum torque (MH) at any S-TBBS-DPG concentration, following a 3D mathematical interpolation/extrapolation procedure, when kinetic constants on few grid points of S-TBBS-DPG concentrations are available. In particular, the possibility to estimate with sufficient accuracy the behavior of natural rubber at any intermediate concentration of S-TBBS-DPG having engineering relevance has been proved, calibrating the model by means of simple closed form standard best fitting on few experimental data. The model used is a three kinetic parameters one, derived from the well known Han's and co-workers approach, where constants have been evaluated normalizing experimental rheometers curves following the commonly accepted Sun and Isayev method. The procedure has been validated against experimentally obtained rheometer curves by means of inverse analysis, exhibiting excellent prediction capabilities. The approach may be used for practical purposes in order to avoid expensive and cumbersome experimental investigations.  相似文献   
148.
149.
《Journal of Non》2006,352(30-31):3196-3199
The expressions for the phonon frequencies of Zr55Cu30Al10Ni15 bulk metallic glass employing a simple model given by Bhatia and Singh for a hypothetical one-component metallic glass are derived both for longitudinal and transverse modes of excitations. The model assumes a central force, effective between the nearest neighbours, and a volume dependent force. Both types of excitations of phonons are computed for the Zr55Cu30Al10Ni15 bulk metallic glass for the first time both for self-consistent screening of conduction electrons with and without the inclusion of correlation effects. Phonon frequency expressions reproduce the main characteristic features of the dispersion curves. The theoretical results predicted are in a good agreement with available experimental data of different quaternary bulk metallic glasses having same constituents. These are also compared to the theoretical results of a quaternary glass to have an insight of the structural behavior of the glass under consideration.  相似文献   
150.
The standard thermodynamic properties of M(OH)2 (M=Mn, Ni and Cd) solid phases have been retrieved using a graphical approach based on the already reportedP vs. T curves obtained from hydrothermal studies of MO-H2O systems. This approach avoids the use of heat capacity effects. The values retrieved by this modified approach are in good agreement with the calorimetric values.
Zusammenfassung Basierend auf unlängst beschriebenen, aus hydrothermischen Untersuchungen von MO-H2O Systemen gewonnenenp-T Kurven wurden mittels einer graphischen Näherung die thermodynamischen Standardeigenschaften von M(OH)2 Festphasen (M=Mn, Ni und Cd) bestimmt. Dieses Verfahren umgeht den Gebrauch von Wärmekapazitätseffekten. Die durch dieses modifizierte Verfahren erhaltenen Werte stehen in guter Übereinstimmung mit den kalorimetrischen Werten.

- , O-H2O, M(OH)2, M=, . . .


The authors express their grateful thanks to Prof. V. Venkatachalapathy, Director of the Minerological Institute, for his encouragement during the course of this work.  相似文献   
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