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71.
John P. Elder 《Thermochimica Acta》1985,95(1):33-40
FORTRAN software is described which enables the generation of rate of weight change data (DTG) from percentage weight change measurements (TG), obtained under non-isothermal conditions. The program also transposes this information into the dimensionless extent and rate of reaction at unit temperature intervals by means of a cubic spline interpolation. A simple search routine identifies all DTG spikes in the thermogravimetric record, and the temperature and extent of reaction at which the rate attains its maximum value. This total information serves as input data for the kinetic analysis software to be discussed in part II of this communication. An example of the application of this program to the pyrolysis of bituminous coal is presented. 相似文献
72.
It is shown that, under certain conditions, the use of Mulliken gross atom populations for the analysis of molecular electronic wavefunctions is not without a basis in the rigorous probabilistic interpretation of quantum mechanics, 相似文献
73.
Fluid flow approximations are widely used for approximating models of communication systems where packet arrival streams are generated in a regular manner over certain intervals (constant rate). The appropriate mathematical model for describing those bursty arrival streams in the fluid flow framework are the well-known Markov modulated rate processes (MMRP). The paper deals with the distribution of the numberN(t) of packets in the interval [0,t] of MMRP. For two-state MMRPs and their superpositions we derive formulas for the distribution ofN(t) and its density. Further we give asymptotic results. The presented numerical results and simulation studies illustrate the goodness of the fluid flow approximation and show that the proposed numerical algorithms work well even in the case of multiplexing a large number of burst silence sources.This work was partially supported by a grant from the Deutsche Bundespost TELEKOM. 相似文献
74.
75.
Microcomputer software for chemists is becoming available at an ever increasing rate. Following Professor Forina's general pattern recognition program, published in last month's Computer Corner, we present a specific technique, the linear learning machine. This is also available in Professor Forina's PARVUS but the software presented here has additional possibilities. It is proposed by Dr D.C. Leegwater from the Central Institute of Food and Nutrition Research of the Dutch organization of Applied Scientific Research (CIVO-TNO) at Zeist and by his son, who is studying physics and mathematics at the State University of Utrecht. 相似文献
76.
Densities of water—glycol (mono- di-, tri- and tetraethyleneglycol) mixtures have been measured over the entire composition range at 298. 15 K. Mixtures involving monoethyleneglycol (MEG) have also been studied at different temperatures from 308.15 to 288.15 K. Deviations, VE, from ideal volumes of mixing have been calculated: negative values are observed for all systems. They increase with the number of ether functions present in the organic molecule; a slight dependence of VE towards temperature has been shown in the water—MEG mixtures. Partial molal volumes have also been calculated for both components of each system; they exhibit an extremum in the water-rich region. 相似文献
77.
Gas phase electron diffraction data for HFDB were analyzed, following conventional procedures, and a structure was deduced for the perfluoro-bicyclo-[2.2.0]hexa-2,5-diene consistent with its C2v symmetry. A least squares analysis of the molecular scattering function gave the following rg values: [-C-C-] = 1.597 ± 0.006 Å, [C-C-] = 1.503 ± 0.002 Å, [-C-C-] = 1.356 ± 0.007 Å, [-C-F](bridge) = 1.331 ± 0.008 Å, [-C-F] (terminal) = 1.323 ± 0.004 Å. The flap angle between the rings is 115.3( ± .7)°. The terminal fluorines are in the planes of the corresponding rings.The most notable feature of the structure is the long C-C bridge bond, which was also observed in hexamethyl-Dewar-benzene. The geometrical features of HFDB are compared with corresponding ones in HMDB, and with perfluoro- cyclobutene as well as with theoretical estimates. 相似文献
78.
The moment generating function of the integrated light intensity of thermal radiation having multiple peak spectrum is obtained.
Cases of two-peak and three-peak spectra where different peaks are in orthogonal states of polarisation are considered. The
moment generating function is shown to be the product of two simpler generating functions. 相似文献
79.
In this article we address an interesting problem in hyperbolic geometry. This is the problem of comparing different quantities associated to the fundamental group of a hyperbolic manifold (e.g. word length, displacement in the universal cover, etc.) asymptotically. Our method involves a mixture of ideas from both ``thermodynamic' ergodic theory and the automaton associated to strongly Markov groups.
80.
采用时域法中的时间相关单光子计数方法记录荧光寿命,时间相关单光子计数采用多波长通道同时记录荧光光子数,可以提高计数效率和信息量,还可以在稳态图像中分离不同荧光团,形成4维图像。并采用多光子激发技术,利用长波长光源发出的两个或多个光子可以激发出一个短波长的光子。多个光子必须几乎同时到达激发点,才能提供被激发分子足够的能量以产生荧光。多光子激发波长较长,生物组织对其散射减小,因而可以穿透到更深层的组织,从而提高荧光成像深度和空间分辨力,并减少对活体样品的损伤。 相似文献