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51.
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
52.
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
53.
54.
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
55.
Peter Šemrl 《Aequationes Mathematicae》1986,31(1):184-190
LetX be a leftA-module, whereA is either a complex Banach *-algebra with an identity element or the field of quaternions. The main result of this note is that forQ, anA-quadratic functional defined onX, there exists a sesquilinear functionalB such thatB(x,x)=Q(x) holds for allxX. 相似文献
56.
Using a construction of Thomassen [Discrete Math. 9, 91–96 (1974)] we prove that for infinitely manyn there is a family
n
of triangle-free maximally non-hamiltonian graphs of ordern with |
n
| exponentially inn. In particular, for everym 48 we construct such a graph; an infinite number of these provide new almost extremal examples in the sense of minimal size. 相似文献
57.
J. Mikuski J. Moravec E. Ochab V. Šára 《Journal of Radioanalytical and Nuclear Chemistry》1981,62(1-2):83-90
The structure of the complex Ag·TBDTPP (tetrabutyl S-dithiopyrophosphate) formed in HNO3 medium was studied by IR and NMR methods. The complex is involved in the isomerization of TBDTPP in the presence of Ag+ and NO
3
−
ions. In the IR spectra, we observe the disappearance of P−O−P band and the occurrence of new absorption bands associated
with P−S−P and P=O bonds. The silver ion is coordinated to the thiophosphoryl group of the isomer molecule. The influence
of HNO3 concentration on complex formation is discussed. 相似文献
58.
Rudovsky J Hermann P Botta M Aime S Lukes I 《Chemical communications (Cambridge, England)》2005,(18):2390-2392
A marked increase of relaxivity has been observed upon rigidifying the internal frame of Gd-containing PAMAM dendrimers: the effect has been attained by either protonation of the dendrimer or by forming supramolecular adducts with cationic polyaminoacids. 相似文献
59.
Summary High-molecular-weight sodium hyaluronate isolated from rooster combs was degraded by ultrasonication. The molecular weight of hyaluronate and its polydispersity was determined by gel-permeation chromatography. During 75-min treatment the molecular weight value decreased from 1.39×106 Da to 2.25×105 Da while the polydispersity of the molecular weight increased from 1.29 to 2.36. The reciprocal value of the square of the hyaluronate's molecular weight was linearly proportional to the time of ultrasonication. 相似文献
60.
Summary A high molecular weight sodium hyaluronate isolated from rooster combs was degraded by ultrasonication. High-performance size exclusion chromatography allowed rapid and accurate determination of molecular weight parameters (Mz, Mw, Mn) and distributions. The time dependence of hyaluronan ultrasonication to the molecular characteristics of the polymer was investigated. A non-random nature of the degradation process was demonstrated and the reciprocal Mn value was found to be linearly proportional to the time of ultrasonication. 相似文献