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81.
The optical-absorption spectra of InP/ZnS (core/shell) quantum dots have been studied in a broad temperature range of T = 6.5–296 K. Using the second-order derivative spectrophotometry technique, the energies of optical transitions at room temperature were found to be E 1 = 2.60 ± 0.02 eV (for the first peak of excitonic absorption in the InP core) and E 2 = 4.70 ± 0.02 eV (for processes in the ZnS shell). The experimental curve of E 1(T) has been approximated for the first time in the framework of a linear model and in terms of the Fan’s formula. It is established that the temperature dependence of E 1 is determined by the interaction of excitons and longitudinal acoustic phonons with hω = 15 meV.  相似文献   
82.
Interaction of hydrogen with the intermetallic compound Nd2Fe17 has been studied for the first time by calorimetry using a differential heat conduction calorimeter coupled to a Sieverts apparatus. Hydrogen absorption and desorption reactions were run at 200°C, and two types of data were obtained: p–C–T and ΔH–C–T (where p is the equilibrium hydrogen pressure, C = H/Nd2Fe17, ΔH is the reaction enthalpy, and T is the measurement temperature). The p–C–T curves obtained for the hydrogen absorption and desorption processes have no plateau or two-phase region, in contrast to what is characteristic of the formation of a hydride phase. At the same time, the ΔH(C) curves have a few portions where the enthalpy of reaction between hydrogen and the intermetallic compound remains constant: 0 < C < 2.0, with ΔH abs =–85.05 ± 0.65 kJ/mol H 2; 2.0 < C < 2.7, with ΔH abs =–80.64 ± 1.00 kJ/mol H2; and 1.9 < C < 2.7, with ΔH des = 76.48 ± 0.85 kJ/mol H2. The data obtained in this study suggest that positions 9e and 18g in the intermetallic compound are occupied by hydrogen in a particular order.  相似文献   
83.
It was found that the domains of the mesophase of the investigated systems have cylindrical symmetry and a different direction of the maximum polarizability: for ethylcellulose and cellulose diacetate, the polarizability is directed along the axis of the cylinder, while it is at an angle of 45‡ for hydroxypropylcellulose. Formation of liquid-crystalline spherulites in the thermotropic transition of isotropic solutions of ethylcellulose in formic acid to the mesophase was demonstrated. In the liquid crystal—isotropic liquid phase transition, a characteristic extreme of the intensity of light scattering is observed near the region of melting of the liquid crystalline matrix, so that this method can be used for identifying the region of the existence of a two-phase “corridor”. Translated from Khimicheskie Volokna, No. 5, pp. 25–27, September–October, 1997.  相似文献   
84.
Conclusions The East Institute of Refractories has developed an effective method of using oxygen for burning the fuel in rotary kilns used for calcining refractory raw materials. The essence of the method consists in feeding oxygen and gas into the combustion chamber in the form of separate jets flowing from the nozzles at sonic and supersonic velocities and aimed at the material being fired.The proposed method is being introduced on rotary kilns for firing dolomite at the Chelyabinsk Factory, as a result of which there has been a big boost in the furnace output, a fall in the specific fuel consumption and dust removal, and also improvements in the quality of the fired powder. The method may be recommended for rotary kilns for firing magnesite and other forms of raw material.Translated from Ogneupory, No. 7, pp. 9–11, July, 1980.  相似文献   
85.
The density of liquid lithium and lithium–lead alloys (10.02 at.% Pb, 14.98 at.% Pb, 18.06 at.% Pb, 20.02 at.% Pb, 22.24 at.% Pb, 23.09 at.% Pb, 25.10 at.% Pb, 30.15 at.% Pb, 38.21 at.% Pb, 40.11 at.% Pb, 43.08 at.% Pb, 46.65 at.% Pb, 50.15 at.% Pb, 60.23 at.% Pb, 70.01 at.% Pb, 83.00 at.% Pb, and 84.30 at.% Pb) has been measured using the gamma-ray attenuation technique over the temperature range from the liquidus line to 1050 K. The position of the liquidus curve in the Li–Pb phase diagram has been clarified. The compositional dependencies of molar volume and volumetric thermal expansion coefficient of the Li–Pb liquid system have been constructed and discussed.  相似文献   
86.
87.
Measurement Techniques - The interaction of two types of modality of a system for processing audiovisual information in the problem of evaluating the emotional state of users of dialogue...  相似文献   
88.
Defined are prospects of using ozone-hydroxyl aerosol blends for treating water by complex effects of electro-plasma charges and UV radiation of water volume under the layer of the air component given the pulse nature of regulating the electric field in the practice of conducting deactivation of impurities of the proposed unit. The use of the given technique of water treatment makes it possible to raise the efficiency of its purification of micromycetes and hardly oxidized organic and mineral pollutants without preliminary use of chemical reagents.  相似文献   
89.
A new algorithm for the suppression of background noise in systems of recognition of voice commands is proposed based on phonetic decoding of words. The principle of the algorithm employs frequencydomain correction of quasi-stationary fragments of the signal of voice command using selective estimation of noise variance in pauses between syllables. The desired effect lies in a several-fold increase in the signal-to-noise ratio at the input of the decision unit. The theoretical results are proven with the aid of a physical experiment.  相似文献   
90.
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