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951.
G. I. Leibengardt A. S. Naidenov V. L. Fedorin V. L. Shur 《Measurement Techniques》1993,36(7):763-766
A two-wave laser interference refractometer for measuring the refractive index of air, pure gases, and gaseous mixtures is described. An algorithm for calculating the results of measurements using the method of coincidence of fractional parts of the orders of interference is given.Translated from Izmeritel'naya Tekhnika, No. 7, pp. 29–31, July, 1993. 相似文献
952.
I. P. Borovinskaya T. P. Ivleva V. E. Loryan K. G. Shkadinskii 《Journal of Engineering Physics and Thermophysics》1993,65(4):988-990
A mathematical model of dissolution of gas in a metal is suggested with account of phase formation in accordance with the phase constitution diagram (PCD). The stage-by-stage saturation process to the final product formation is shown for an individual particle, through which a reaction wave passes, depending on the diffusion permeability of the metal and solubility conditions that obey Sieverts's law. The effect of the filtration supply of the oxidant to the reaction zone and the process exothermicity on the course of the process is shown.Institute of Structural Macrokinetics, Russian Academy of Sciences, Chernogolovka, Russia. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 65, No. 4, pp. 447–450, October, 1993. 相似文献
953.
954.
B Neppolian H C Choi S Sakthivel Banumathi Arabindoo V Murugesan 《Journal of hazardous materials》2002,89(2-3):303-317
The photocatalytic degradation of three commercial textile dyes with different structure has been investigated using TiO(2) (Degussa P25) photocatalyst in aqueous solution under solar irradiation. Experiments were conducted to optimise various parameters viz. amount of catalyst, concentration of dye, pH and solar light intensity. Degradation of all the dyes were examined by using chemical oxygen demand (COD) method. The degradation efficiency of the three dyes is as follows: Reactive Yellow 17(RY17) > Reactive Red 2(RR2) > Reactive Blue 4 (RB4), respectively. The experimental results indicate that TiO(2) (Degussa P25) is the best catalyst in comparison with other commercial photocatalysts such as, TiO(2) (Merck), ZnO, ZrO(2), WO(3) and CdS. Though the UV irradiation can efficiently degrade the dyes, naturally abundant solar irradiation is also very effective in the mineralisation of dyes. The comparison between thin-film coating and aqueous slurry method reveals that slurry method is more efficient than coating but the problems of leaching and the requirement of separation can be avoided by using coating technique. These observations indicate that all the three dyes could be degraded completely at different time intervals. Hence, it may be a viable technique for the safe disposal of textile wastewater into the water streams. 相似文献
955.
Storozhuk V. N. Romashchenko V. A. Lepikhin P. P. Zhurakhovskii S. V. 《Strength of Materials》2002,34(3):300-304
Large deflections of pulse-loaded elliptic and round plates made of hardenable elastoplastic materials are investigated analytically using an energy-based approach. Formulas that are convenient for engineering design have been derived. 相似文献
956.
Batch process industries are characterized by complex precedence relationships between operations, which renders the estimation
of an acceptable workload very difficult. A detailed schedule based model can be used for this purpose, but for large problems
this may require a prohibitive large amount of computation time. We propose a regression based model to estimate the makespan
of a set of jobs. We extend earlier work based on deterministic processing times by considering Erlang-distributed processing
times in our model. This regression-based model is used to support customer order acceptance. Three order acceptance policies
are compared by means of simulation experiments: a scheduling policy, a workload policy and a regression policy. The results
indicate that the performance of the regression policy can compete with the performance of the scheduling policy in situations
with high variety in the job mix and high uncertainty in the processing times.
Correspondence to: C.V. Ivanescu 相似文献
957.
Rao V. Garimella 《International journal for numerical methods in engineering》2002,55(4):451-478
The data structure representing a mesh and the operators to create and query such a database play a crucial role in the performance of mesh generation and FE analysis applications. The design of such a database must balance the conflicting requirements of compactness and computational efficiency. In this article, 10 different mesh representations are reviewed for linear tetrahedral and hexahedral meshes. A methodology for calculating the storage and computational costs of mesh representations is presented and the 10 data structures are analysed. Also, a system for ranking different data structures based on their computational and storage costs is devised and the various mesh representations are ranked according to this measure. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
958.
V. B. Baiburin Yu. P. Volkov E. M. Il’in S. V. Semenov 《Technical Physics Letters》2002,28(12):981-982
The surface of a palladium-barium cathode was studied using scanning probe microscopy techniques. Data from the tunneling spectroscopy showed the pattern of the electron work function distribution over a microscopic region on the emitter surface. This pattern is compared to the distribution of various phases in the palladium-barium alloy employed. 相似文献
959.
S. F. Pankina V. V. Chebotaev V. A. Il'ichev V. P. Petrukhin I. V. Kolybin 《Soil Mechanics and Foundation Engineering》1998,35(2):55-60
A general concept is cited for the design of an underground transportation tunnel in the Lefortovo District. Attention is
focused on problems of the tunnel's layout in plan and profile, the layout of sections, and selection of the driving technology.
Results are presented for the numerical modeling of variations in the stress—strain state of the soil mass, which are associated
with the tunnel's installation. A set of measures to protect existing architectural monuments is proposed.
Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 2, pp. 17–21, March–April, 1998. 相似文献
960.