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81.
A. N. Kulik A. N. Bugai Yu. V. Rogul’skii T. G. Kalinichenko 《Journal of Applied Spectroscopy》2009,76(4):564-569
We have used scanning electron microscopy to study changes in the morphology of the inner surface of graphite tube furnaces
for an atomic absorption spectrometer when modified by tungsten. We have demonstrated the role of the tungsten-containing
material as a dividing interlayer between the sample to be dispensed and the carbon component of the furnace. We consider
the advantages and disadvantages of furnaces modified by the proposed methods. 相似文献
82.
JETP Letters - A simple fundamental modification of quantum key distribution protocols has been proposed: it is not required to protect the results of avalanche detectors from an eavesdropper, but... 相似文献
83.
Yuliya V. Rassukana Ludmyla V. Bezgubenko Oleg V. Stanko Eduard B. Rusanov Irina B. Kulik Petro P. Onysko 《Tetrahedron: Asymmetry》2017,28(4):555-560
The cycloaddition reaction of (S)-(α-phenylethylimino)trifluoropropionate with diazomethane leads to a diastereomeric mixture (4.5:1) of 5-trifluoromethyl-1,2,3-triazoline-5-carboxylates. Enantiopure diastereomers were isolated by column chromatography and converted into their respective non-racemic 2-trifluoromethyl-aziridine-2-carboxylates and carboxylic acids. The absolute configuration of newly formed stereogenic centers was determined by XRD analysis. The stereoselective reaction between (S)-N-(α-phenylethyl)trifluoroacetimidoylphosphonate and diazomethane produces a diastereomeric mixture (2.5:1) of 5-trifluoromethyltriazoline-5-phosphonates readily separated by column chromatography in diastereomerically pure forms. 相似文献
84.
We consider bounded invariant manifolds of autonomous systems of differential equations and study the problem of their continuity
and continuous differentiability with respect to a parameter. 相似文献
85.
86.
R.I. Dzhelyadin S.V. Golovkin M.V. Gritsuk D.B. Kakauridze V.A. Kachanov A.K. Konoplyannikov A.S. Konstantinov V.F. Konstantinov V.P. Kubarovski A.V. Kulik L.G. Landsberg V.M. Leontiev V.A. Mukhin V.F. Obraztsov T.I. Petrunina N.S. Pokrovski Yu.D. Prokoshkin V.A. Victorov A.M. Zaitsev 《Physics letters. [Part B]》1979,84(1):143-144
The results of studying the mass spectrum of μ+μ?γγ systems produced in π?p collisions at 25 and 33 GeV/c presented. The wide-aperture magnetic spectrometer with a hodoscope γ-detector was used to identify muon pairs and photons. There is a clear peak in the mass spectrum which corresponds to the decay ω → π0μ+μ? previously not observed. The branching ratio for the decay is estimated to be 9 × 10?5 with a systematic error of 50%. 相似文献
87.
88.
S.?N.?Danil’chenkoEmail author A.?N.?Kulik A.?N.?Bugai P.?A.?Pavlenko T.?G.?Kalinichenko N.?V.?Ul’yanchich L.?F.?Sukhodub 《Journal of Applied Spectroscopy》2005,72(6):899-905
Using x-ray diffraction, electrothermal atomization atomic absorption spectroscopy, and scanning electron microscopy with
an x-ray microanalysis, we have studied the phase decomposition of biogenic and synthetic Mg-containing apatite at 900°C with
formation of β-tricalcium-magnesium phosphate (β-TCMP). Employing simplified model representations, we obtained a relation
that couples the initial Mg concentration with the degree of transformation of apatite into β-TCMP. It is shown that for the
β-TCMP contents measured in bioapatite samples and on replacement of calcium by magnesium to about 8% in this phase the calculated
range of Mg concentrations coincides with that available in literature sources (0.2–0.6 wt. %). A comparative investigation
of the products of decomposition of biogenic and synthetic apatite by the methods of analysis of the composition and structure
has established that the formation of β-TCMP is limited by both the insufficient concentration of magnesium and the small
sizes of the crystals. The results of the investigations carried out together with the experimental data known from the literature
are indicative of the nonuniform distribution of magnesium in the bulk of crystals of biogenic and synthetic apatite, with
its predominant localization at the surface sites of the lattice.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 72, No. 6, pp. 821–826, November–December, 2005. 相似文献
89.
Yu. I. Bogdanov R. F. Galeev S. P. Kulik G. A. Maslennikov E. V. Moreva 《JETP Letters》2005,82(3):164-168
A method for reconstructing an arbitrary quantum state of an optical system in Hilbert space with dimension d = 4 is discussed. Such states can be realized using a collinear frequency-nondegenerate regime of generating spontaneous parametric down-conversion. The method has been tested for a number of polarization states of a biphoton field. The high accuracy of the reconstruction of the states (above 99%) indicates that the procedures proposed for reconstructing the quantum state of the system are adequate. 相似文献
90.
V. I. Vettegren V. A. Marikhin V. B. Kulik L. S. Titenkov 《Physics of the Solid State》2003,45(4):788-792
The temperature dependence of the half-width of the infrared (IR) absorption band at a frequency of 971.5 cm?1 in the spectra of poly(ethylene terephthalate) (PET) is investigated for crystallized and amorphous PET samples in which the lengths of trans sequences are approximately equal to 4–7 and 2–3 nm, respectively. The observed increase in the half-width with increasing temperature is explained by inelastic scattering of phonons of stretching vibrations of the macromolecular skeleton by other phonons. The half-width of the band at 971.5 cm?1 in the IR spectra of the amorphous polymer is approximately 1.5 times larger than that in the spectra of the crystallized polymer. This is associated with the violation of the wave-vector selection rules due to a small length of the trans sequences in the amorphous sample. 相似文献