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41.
The phase analysis of cryolite (Na3AlF6) and sodium metasilicate (Na2SiO3) was performed by thermal analysis. The eutectic system with a region of two immiscible substances at a concentration of Na2SiO3 between 42.8 and 46.3 mol‐% was identified and the eutectic temperature determined to (886±2) °C. Based on the results of mass‐loss measurements, it was assumed that the introduced Na2SiO3 reacts with Na3AlF6 due to the formation of some nonvolatile stable compounds. The stable reaction products were identified by X‐ray diffraction analysis and IR spectroscopy of the spontaneously cooled samples, which established the formation of NaF and stable amorphous aluminosilicate compounds. 相似文献
42.
Sodium hexafluoromanganate(III) has been synthesized by heating equimolecular quantities of Na2MnF5 and NaF in argon atmosphere. The compound is monoclinic witha=5.56 (1) Å,b=5.84 (1) Å,c=8.10 (2) Å, =90.7 (2) andZ=2. It is a high spin complex with
eff
and the deformation of the octahedra is evident from its IR-spectra. Two enantiotropic transitions (at 562 and 653°C) and the melting point at 800°C have been observed.
8. Mitt.: Mh. Chem.106, 483 (1975). 相似文献
8. Mitt.: Mh. Chem.106, 483 (1975). 相似文献
43.
The mechanism of the unfolding of human serum albumin by urea was studied using d.c. polarography. It was found that this reaction is a complex process which cannot be described in terms of a two-state transition model. As well as the Brdi?ka catalytic current we have also studied the reduction current of disulfide groups in native and denatured human serum albumin. The number of cystine residues accessible for electrode reduction in native and denatured protein was calculated. On the basis of these results a scheme for the unfolding of human serum albumin by urea is proposed. 相似文献
44.
The reconstruction numberrn(G) of a graphG was introduced by Harary and Plantholt as the smallest number of vertex-deleted subgraphsG
i
=G – v
i
in the deck ofG which do not all appear in the deck of any other graph. For any graph theoretic propertyP, Harary defined theP-reconstruction number of a graph G P as the smallest number of theG
i
in the deck ofG, which do not all appear in the deck of any other graph inP We now study the maximal planar graph reconstruction numberrn(G), proving that its value is either 1 or 2 and characterizing those with value 1. 相似文献
45.
L. Avanov N. Borodkova Z. NĚmeček A. Omeltchenko J. Šafránková A. Skalski Yu. Yermolaev G. Zastenker 《Czechoslovak Journal of Physics》1987,37(6):759-774
The paper describes the results of investigations of the solar wind ions, carried out on board the high apogee Prognoz 7 and Prognoz 8 Earth's satellites with the aid of an SKS instrument (USSR) and a Monitor instrument (USSR-SSR). Behaviour of proton and that of components on the front of Earth's bow and interplanetary shock waves were compared by means of the energoanalysis and energy-mass analysis techniques. In several long-term periods of observation the solar wind heavy ions — oxygen, silicon and iron were determined. It enabled us to estimate the solar corona chemical composition and electron temperature.Presented at the 5th General Assembly IAGA/IAMAP August 5–17, 1985, Prague, Czechoslovakia. 相似文献
46.
The dependence of the flow stress and the slip band density on the plastic strain has been measured at 201 K, 293 K and 363 K. The growth of deformation concentrated in an average slip band has been stated. The types of obstacles acting against the rise and development of a slip band and the temperature dependence of the strain hardening in AgCl crystals are discussed. An equation stating the dependence of the flow stress on the slip band density is presented. The hardening in AgCl crystals is classified as the stage III — hardening. 相似文献
47.
A hybrid method for measuring the electron distribution function in the low temperature plasma is described. The time resolution of the measurement is of the order of several sec. 相似文献
48.
The valence electron states of layered semiconductor GaS were studied by polarizedK X-ray emission bands. The polarized gallium and sulphurK bands were calculated and GaK2-bands were measured by the two crystal spectrometer. In the calculations the self-consistent pseudo-potential method was applied. Thep
x
,p
y
p
z
-character and localisation of valence electron states were identified. Comparison with the results of controversial interpretation of photoemission and tight binding calculations were done and analysed in detail.We are indebted to J. Mikkelsen from Xerox Research Center in Palo Alto for kindly sending us the GaS single crystals. 相似文献
49.
50.
Multiplicity distributions up to the Collider energies could be described by various two-parameter compounded distributions having in common Poisson distributed number of clusters. Among them the logarithmic distribution for hadronization via decaying clusters leads to energyindependent number of clusters above the ISR energies, replacing the previous KNO-scaling.Dedicated to the 30th anniversary of the Joint Institute for Nuclear Research. 相似文献