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61.
本文介绍了尼龙1010的结晶过程与动力学、晶体的熔融与转化;并论述了其稀溶液、热降解与动态力学性质及共聚、共混、填充、增强、交联改性方面的研究进展。 相似文献
62.
R. C. Milward 《Fresenius' Journal of Analytical Chemistry》1973,264(3):195-199
Summary This article describes a new commercial Far-Infrared Fourier Spectrometer system which has been developed for routine spectroscopy in the 10–1000 cm–1 spectral region. The instrument incorporates real-time data processing and has been automated wherever possible for foolproof operation. A versatile sample chamber allows a wide range of spectroscopic studies to be performed, on solids, liquids and gases over a wide range of temperatures. A number of spectra are presented to illustrate the performance and typical applications of this Fourier spectrometer.
Ein neues fourier-spektrometer für das ferne infrarot
Zusammenfassung Nach einer kurzen Einführung in die Methode der Fourier-Spektroskopie wird ein neues kommerzielles Fern-Infrarot-Fourier-Spektrometer mit real-time Datenverarbeitungsanlage beschrieben. Das Gerät ist für die Spektroskopie im Bereich 10–1000 cm–1 konstruiert und weitgehend automatisiert. Eine vielseitig verwendbare Probenkammer ermöglicht umfangreiche spektroskopische Untersuchungen von Festkörpern, Flüssigkeiten und Gasen in einem sehr großen Temperaturbereich. Anhand einer Reihe von Spektren werden Leistung und typische Anwendungen dieses Fourier-Spektrometers erläutert.
Lecture presented at Euroanalysis I Conference, 28. 8.–1. 9. 1972 in Heidelberg, Germany. 相似文献
63.
A. Gameiro Pais 《Aequationes Mathematicae》1984,27(1):49-56
This paper is concerned with the problem of solving linear difference equations of ordern with constant coefficients and with given initial conditions in which the variable runs not only through the integers but over . The main idea is the introduction of a suitable commutative ring of functions with discrete convolution as multiplication rule which works, although it is not a field. The existence of inverses is studied and, after the introduction of suitable functions, the problem is reduced by means of a Laplace-like relation to an algebraic equation. Examples of application are given. Finally some remarks make the connection with the Operational Calculus of Mikusinski and with the Operational Calculus of Fenyö. The advantages of this method lie in the fact that it is applicable to functions others than the step functions, in its simplicity from the theoretical point of view, in its usefulness even when computation is required and in its formal similarity to the classical treatment of linear differential equations with constant coefficients. 相似文献
64.
B. Gyires 《Periodica Mathematica Hungarica》1978,9(1-2):109-113
This paper contains applications of theorems of [1] for quadratic statistics which have constant regression on linear statistics. Two theorems are proved. The first is a sufficient condition which assumes that the characteristic function of a sample is an entire function. The second gives a new characterization of the normal distribution. 相似文献
65.
P. Vértesi 《Periodica Mathematica Hungarica》1978,9(3):249-254
Summary In his paper [1]P. Turán discovers the interesting behaviour of Hermite-Fejér interpolation (based on the ebyev roots) not describing the derivative values at exceptional nodes {n}
n=1
. Answering to his question we construct such exceptional node-sequence for which the mentioned process is bounded for bounded functions whenever –1<x<1 but does not converge for a suitable continuous function at any point of the whole interval [–1, 1]. 相似文献
66.
James V. Crivello Mingxin Fan 《Journal of polymer science. Part A, Polymer chemistry》1992,30(1):31-39
In the presence of Si? H containing cocatalysts, dicobaltoctacarbonyl has been found to very efficiently catalyze the ring-opening polymerization of cyclic ethers, especially epoxides, as well as certain vinyl monomers. The reaction conditions employed are very similar to those used in Co2(CO)8 catalyzed hydrogenation and hydrosilylation reactions. Detailed investigations have been carried out to elucidate the nature of the active species for this catalytic system. A cationic mechanism is proposed based on the experimental results of those investigations. 相似文献
67.
C. Ferrero M. N. Martino N. E. Zaritzky 《Journal of Thermal Analysis and Calorimetry》1996,47(5):1247-1266
Differential scanning calorimetry (DSC) was used to analyze the influence of different hydrocolloids (xanthan, guar, and locust bean gums, carboxymethylcellulose and sodium alginate) on the gelatinization of corn starch in systems with starch concentration ranging between 0.1 and 0.7 g starch/g mixture. The reduction of available water produced a shift in gelatinization temperature, especially of the conclusion temperature. The effect was more marked for ionic hydrocolloids. The influence of hydrocolloids on glass transition temperature (T
g) of gelatinized starch suspensions and on the glass transition temperature of the maximally freeze-concentrated solute/unfrozen water matrix (T
g) was also studied.T
g onset values ranged between –4.5 and –5.5C for corn starch pastes with and without hydrocolloids. Those hydrocolloids that increased the viscosity of the unfrozen matrix inhibited additional ice formation during thawing (devitrification).Starch concentration and final heating temperature were found to be relevant factors affecting the kinetics of amylopectin retrogradation during frozen storage at –4C. Xanthan gum failed to prevent amylopectin retrogradation; this observation could be attributed to the fact that gums act outside the starch granule, while amylopectin retrogradation takes place within the granule. 相似文献
68.
Shie-Shien Yang 《Annals of the Institute of Statistical Mathematics》1981,33(1):463-470
Summary Let (X
1,Y
1), (X
2,Y
2),…, (X
n,Y
n) be i.i.d. as (X, Y). TheY-variate paired with therth orderedX-variateX
rn is denoted byY
rn and terms the concomitant of therth order statistic. Statistics of the form
are considered. The asymptotic normality ofT
n is established. The asymptotic results are used to test univariate and bivariate normality, to test independence and linearity
ofX andY, and to estimate regression coefficient based on complete and censored samples. 相似文献
69.
H. Groemer 《Aequationes Mathematicae》1981,22(1):215-222
In the euclidean planeE
2 letS
1,S
2, ... be a sequence of strips of widthsw
1,w
2, .... It is shown thatE
2 can be covered by translates of the stripsS
i if w
1
3/2
= . Further results concern conditions in order that a compact convex domain inE
2 can be covered by translates ofS
1,S
2, ....This research was supported by National Science Foundation Research Grant MCS 76-06111. 相似文献
70.
B. Rendi 《Periodica Mathematica Hungarica》1977,8(3-4):225-228
Sans résumé
The article is the text of a talk given at the Symposium on Differential Geometry in Debrecen, Hungary, on August 28–September 3, 1975. 相似文献