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Miloslav Duchoň Anatolij Dvurečenskij Paolo de Lucia 《International Journal of Theoretical Physics》1997,36(9):1941-1958
We present a solution to the moment problem for effect algebras, concerning mean values of all powers of an observable concentrated
on the interval [0, 1] for states from a convex set. We give a solution for particular examples, e.g., for the set of all
effect operators. We examine how this problem is related to a socalled E-property. Finally, we give a solution for observables
studied in the operational approach to physical theories. 相似文献
4.
Miloslav Ku
ra Eduard Hladký Karla Majerov 《Journal of polymer science. Part A, Polymer chemistry》1967,5(8):1889-1898
Water acts as a cocatalyst in the polymerization of dioxolane initiated by the ion pair ~Si⊕HSO4?. The dependence of the reaction rate on the water concentration exhibits a maximum, the width of which strongly depends on the concentration of dioxolane. The change of the coordinates of the maximum and its shape with the decrease of the monomer concentration causes the reaction rate to decrease with increasing conversion. The point at which the slope of the conversion curve changes is a function of initial concentration of water. There is a very fast decrease of the concentration of free water in the polymerizing system. The consumption of water is associated with some peculiarities. The amount of free water which remains in the system is a function of the concentration of the original initiator. The ratio [H2O]∞/[initiator] is constant over a rather broad range of initial concentration of water. 相似文献
5.
Accumulation of five heavy metal ions by five species of wood-rotting basidiomycetes during a 9-day cultivation was studied. Contents of Cd, Cu, Pb, and Zn were measured using ICP-MS; the amount of mercury was determined directly in solid samples using the Advanced Mercury Analyser. A standard operation procedure for the sample preparation and determination of metal content was developed and validated. Presence of Cd, Cu, Hg, and Pb decreased the accumulation of zinc by the fungi. The basidiomycete Pycnoporus cinnabarinus exhibited the highest metal binding capacity of all fungi tested. 相似文献
6.
Suspensions of lignite in a solution of a high molecular weight carboxymethylcellulose show peculiar rheological behaviour.
Unless the lignite concentration is sufficiently high, apparent viscosity and viscoelastic moduli of the suspension are lower
than those of the pure solution. This effect is not suppressed by changing pH and seems to be common for low-concentrated
suspensions in solutions of high molecular weight (bio)polymer. It is explained by specific structuring of the suspensions.
Lignite particles at lower concentration separate long cellulose chains and facilitate their movement under shear flow. The
particles loosen inter-chain contacts, disturb and release elastic gel-like structure formed by the long cellulose chains,
which results in the low strain oscillatory deformation, the decrease in the moduli and the increase in the loss angle. If
the amount of lignite particles is sufficiently high, suspension stiffening occurs as usual. No such effect was observed for
suspensions prepared from the low molecular weight derivative.
Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users. 相似文献
7.
Samples of poly(12-dodecanelactam) (polylaurolactam, nylon 12) with n 1 × 103?33 × 103 were prepared. Polymerizations initiated with water or with lauric acid proceeded under conditions for minimum changes in end-group concentration. Values of n were calculated from the end-group content and n from light scattering in the mixture m-cresol/60 vol% of 2.2,3,3-tetrafluoropropanol. From measurements of intrinsic viscosity in m-cresol, the relationship [n] ? n was established in the given range of n. The relationship [n] ? w for w from 3.3 × 103 to 125 × 103 has been established. 相似文献
8.
The viscosity interaction coefficient, kAB, for the system poly(vinylalcohol)-polyacrylamide-water was determined at 25° by two methods: (a) estimation of the Huggins slope coefficients for mixtures of polymers in different proportions; (b) determination of the intrinsic viscosity of polymer (A) in aqueous solutions of polymer (B). The result, kAB = 0.3, indicates a low degree of overlapping of unlike polymer molecules. 相似文献
9.
Miloslav Vobecký und Jaroslav Bene 《Fresenius' Journal of Analytical Chemistry》1965,213(6):404-408
Zusammenfassung Eine Methode zur schnellen und selektiven Trennung von Barium aus einem Gemisch von Spaltprodukten wurde ausgearbeitet, die auf der Fällung des Bariumsulfats in Anwesenheit von äDTA beruht. Die Selektivität wurde durch Messung der -Spektren und der Zerfallskurven ÜberprÜft. Die Schnelligkeit der Methode wird durch die Abtrennung des Kernisomers 137m Ba aus einem im Gleichgewicht befindlichen Gemisch von 137m Ba und 137Cs gezeigt.Das angefÜhrte Verfahren eignet sich fÜr die Herstellung von radiochemisch reinem Barium, fÜr die quantitative Auswertung der Kontamination der Spaltprodukte und fÜr die Berechnung des Alters radioaktiver atmosphärischer Niederschläge.
Summary A method has been developed for the rapid and selective isolation of barium from a mixture of fission products, based on precipitating barium sulphate in EDTA medium. The selectivity was checked by measuring -spectra and by decay curve analysis. The rapidity of the method is illustrated by the isolation of the 137mBa isomer from an equilibrium mixture of 137Cs+137m Ba.The method described is convenient for preparing radiochemically pure barium, for a quantitative evaluation of a decontamination with fission products and for determining the age of radioactive fall-out.相似文献
10.
For a number of fractions and unfractionated samples of polylaurolactam, molecular weights () were measured by the light-scattering method in a mixed solvent of m-cresol with 60 vol. % 2,2,3,3-tetrafluoropropanol; intrinsic viscosities were determined in m-cresol and 96% H2SO4, and the constants of the Mark-Houwink equation were calculated. The calculated values of the characteristic ratio of unperturbed dimensions (virtually identical for m-cresol and 96% H2SO4) were compared with the respective values for polypyrrolidone and polycaprolactam. It was found that the higher frequency of the CONH-groups reduces the rigidity of the polyamide chain. 相似文献