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31.
O. V. Nestroinaya I. G. Ryl’tsova O. E. Lebedeva B. M. Uralbekov O. I. Ponomarenko 《Russian Journal of General Chemistry》2017,87(2):163-167
A series of multi-component layered double hydroxides with hydrotalcite structure containing doubly charged magnesium and cobalt cations and triply charged aluminum and iron cations in the brucite-like layers have been synthesized by co-precipitation at variable pH. Formation of the hydrotalcite structure has been confirmed by X-ray diffraction analysis. Thermal behavior of the synthesized samples has been studied by IR spectroscopy, thermogravimetry, and differential thermal analysis. 相似文献
32.
V. M. Orlovskii É. A. Sosnin V. F. Tarasenko A. G. Ponomarenko Yu. I. Khapov 《Technical Physics》1999,44(1):69-73
Results are presented from a study of HF lasers pumped by non-chain chemical reactions initiated by a radially convergent
and by a planar electron beam. The main channels of formation of vibrationally excited HF molecules are analyzed. The distribution
of the energy density of the radiation in the output beam of a wide-aperture laser is measured. In 30 liters of a mixture
of SF6:H2=8:1 at a pressure of 1.1 atm an output energy of ∼200 J is obtained at an ∼11% efficiency with respect to the energy deposition.
It is shown that the admixture of a buffer gas of neon or argon improves the uniformity of the radiation energy distribution
in the output beam of an HF laser pumped by a non-chain chemical reaction and initiated by an electron beam, and it also increases
the output energy.
Zh. Tekh. Fiz. 69, 76–81 (January 1999) 相似文献
33.
34.
Ilia Rodushkin Emma Engström Douglas C. Baxter 《Analytical and bioanalytical chemistry》2013,405(9):2785-2797
This critical review focuses on inductively coupled plasma mass spectrometry (ICP-MS) based applications for isotope abundance ratio measurements in various clinical samples relevant to monitoring occupational or environmental exposure, human provenancing and reconstruction of migration pathways as well as metabolic research. It starts with a brief overview of recent advances in ICP-MS instrumentation, followed by selected examples that cover the fields of accurate analyte quantification using isotope dilution, tracer studies in nutrition and toxicology, and areas relying upon natural or man-made variations in isotope abundance ratios (Pb, Sr, actinides and stable heavy elements). Finally, some suggestions on future developments in the field are provided. 相似文献
35.
Radu Vacaronceanu Gheorghe Ilia Ludovic Kurunczi Petria Şoimu 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract The study of GC separation of 2-chloroethylphosphonic acid di-n-alkyl (1–5 C atoms) esters (synthesised by us) on silicone stationary phases (OV-1, OV-17, OV-225) revealed a deviation from the expected linear dependence of retention indexes (RI) versus the number of C atoms of the alkyl chain: the first member of the series presents stronger retention than one can expect. This anomalous behaviour was observed especially on polar stationary phase (OV-225, see Figure l), and was emphasised with the increase of the column temperature. In an attempt to rationalise the above mentioned facts, we tried to relate the RI values to a global polarity parameter: the dipole moment, μ. The μ values for ClC2H4P(O)(OR)2 were calculated by a method described in [1] (tested by comparing the calculated μ values with experimental ones for alkyl phosphonic acid dialkylesters), using molecular mechanics (COSMIC package) in the search of the conformational space, AM1 method (MOPAC 6.0) for the μ values of the conformers, and Boltzmann distribution for the global value (see Table I). At low temperature, the μ values are not related to the Kovats indexes. Those calculated at 200°C (column temperature range) demonstrate that, indeed, only in the case of the methyl derivative, the temperature rising led to a higher μ (enhanced population of the more polar conformers: ac position for the C-Ethyl group - ac for the Cl, μ ≈ 27 D, or ±ap for one R, μ ≈ 3.8 ÷ 4.3 D). It can be concluded that dipole-dipole forces contribute to the separation process of the first members of the series. 相似文献
36.
Gheorghe Ilia Adriana Popa Smaranda Iliescu Alina Bora Gheorghe Dehelean Aurelia Pascariu 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1513-1519
Some mixed phosphites having two different alkyl chain were obtained as forerunners for mixed phosphates Mixed dialkyl phosphates were obtained in good yields (40-80%) by phase transfer catalysis in liquid-liquid sistem, starting from different dialkyl phosphites and aliphatic alcohols. The reaction conditions were optimized in order to obtain good yields in phosphites and phosphates respectively. Compounds were analyzed by IR, P 31 -NMR. 相似文献
37.
Romana Pajkert Tobias Böttcher Maksym Ponomarenko Matthias Bremer Gerd-Volker Röschenthaler 《Tetrahedron》2013
A series of novel push–pushI and push–pullII carbene-stabilized complexes of phosphorus(V) fluorides bearing substituents with liquid-crystalline properties were synthesized by the oxidative addition of difluoroamines to phosphorus(III) halides. These octahedral complexes were characterized by NMR spectroscopy and X-ray analysis. 相似文献
38.
We derive a complex area correlation theorem describing global second-order statistical properties of pulses propagating in coherent linear absorbers. We also illustrate temporal evolution of a generic partially coherent pulse in a coherent linear absorber by discussing the behavior of its temporal intensity profile and degree of coherence. 相似文献
39.
40.
The automatic image analysis system for scanning solid state nuclear track detectors is designed by utilizing a microdensitometer. The control of the entire system as well as the data analysis are accomplished with the IBM PC computer equipped with a FrameGrabber. The system counts the number of tracks and measures their geometrical parameters. The usage of the system is illustrated by counting rhombic tracks in mica detectors which were used for the investigation of the fusion–fission reaction 12C+ 208Pb. 相似文献