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421.
The interaction of the monel alloy and its corrosion resistance in a melt of alkali metal carbonates in an oxidizing atmosphere was studied. The selectivity of alloy dissolution and modification of the electrode surface after storage at a constant anode potential were analyzed. The generation and development of local corrosion defects (pit corrosion, intercrystallite corrosion, corrosion cracking) on monel alloy (70% nickel, 28% copper), copper, and nickel electrodes in the molten eutectic of lithium, sodium, and potassium carbonates at a working temperature of 773 K were studied. The anode polarization was accompanied by a change in the state of the electrode surface.  相似文献   
422.
This work reviews the status of the international OPERA experiment aimed at searching for the νμ → ντ oscillation. Development of the emulsion techniques in the preceding DONUT and CHORUS experiments is described. A brief overview of the NOMAD experiment is given, in which properties of ντ interactions were thoroughly investigated. Characteristics of the CERN-Gran Sasso (CNGS) neutrino beam are given, the structure of the OPERA hybrid detector and the functions of its subsystems are considered, and the automatic emulsion scanning technique is briefly reviewed. Uncertainties in reconstruction of event parameters using the electronic and emulsion detectors are discussed and the procedure adopted in the experiment for identification of ντ interactions is described. The main sources of background in the search for νμ → ντ oscillation are considered. Topologies of the first two ντ candidates observed in the OPERA emulsion detector are presented. Possibilities of increasing the ντ interaction selection efficiency using multidimensional criteria are briefly discussed.  相似文献   
423.
Total probabilities A nl of spontaneous radiative transitions, which determine lifetimes τ nl = 1/A nl of nS-, nP-, nD- and nF-states in singly charged ions of the group IIa (Be+, Mg+, Ca+, Sr+, Ba+) and IIb (Zn+, Cd+, Hg+) elements, were calculated in the single-electron Fues’ model potential (FMP) method. An asymptotic dependence is determined for highly excited states with small angular momentums and presented in the form τ nl = τ l (0) n 3 Q l (1/n) and numerical values of the factors τ l (0) and coefficients of the cubic polynomial Q l (x) are calculated, which approximate results of numerical computations with relative error below 2% in the range of states with principal quantum numbers from n = 7 to n ≈ 2000. The comparison of the numerical results with data in literature is presented, and applicability and reliability of single-electron model calculations are discussed in detail for positive singly charged ions of the group II elements.  相似文献   
424.
We have studied the effect of small additives of Pt and Pd on the hydrogen sensitivity of semiconductor adsorption sensors based on SnO2 and on the catalytic activity of sensor materials of the same composition in oxidation of hydrogen. We have shown that as the amount of Pt or Pd increases, the catalytic activity increases and the sensitivity of the sensors passes through a maximum. The results obtained are explained taking into account the hydrogen spillover phenomenon. __________ Translated from Teoreticheskaya i Eksperimental'naya Khimiya, Vol. 41, No. 5, pp. 302–306, September–October, 2005.  相似文献   
425.
426.
Fluorescent properties of some cross-conjugate ketones were studied at 4.2, 77, and 300 K. Anomalies were observed in the fluorescence and fluorescence-excitation spectra of one of the studied compounds; these anomalies consisted in a pronounced upset of mirror symmetry of the spectra and a large Stokes shift. The experimental spectra and the spectra calculated theoretically using the theory of two-well adiabatic potentials were subjected to a comparative analysis.  相似文献   
427.
Conditions are established under which a standard limit cycle occurs in the system under consideration, or the trajectory closes under the influence of a stagnation domain. It is pointed out that when the solution falls into the stagnation domain it makes no sense to use the asymptotic method because of a large error __________ Translated from Prikladnaya Mekhanika, Vol. 42, No. 2, pp. 104–112, February 2006.  相似文献   
428.
Alkylthiochloroacetylenes regio- and stereospecifically react with di(2-phenylethyl)phosphine oxide in dioxane at 20-22°C in the presence of potassium hydroxide to form 1-chloro-2-(alkylthio)vinyl[di(2-phenylethyl)]phosphine oxides in a 78-85% yield. According to IR and 1H and 3 1P NMR data, dielectrometric measurements, and quantum-chemical calculations, the obtained adducts have the Z configuration and exist mainly in the sp,sp conformation.  相似文献   
429.
Both exo- and endo-isomers of 4-phenyl-3,5,8-trioxabicyclo[5.1.0]octane were reacted with thiophenol to afford individual diastereomers of hydroxy sulfides which were further processed in search for new antimycotic substances.  相似文献   
430.
Russian Chemical Bulletin - One-dimensional coordination polymer was obtained by cation exchange reaction of triethylammonium salt of methyl ent-16α-H-phosphonyloxybeyeran-19-oate with CuCl2....  相似文献   
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