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1.
We studied the influence of the lubricant compositions Grafitol with 10% graphite (1), Aerol containing 17% MoS2 (2), Limol containing 60% MoS2 (3), Limol + 10% chlorine-paraffin (4), and Limol + 10% copper powder (5) on the wear rate and formation of the fine structure of surface friction layers of structural steels. We established a correlation between the tribological characteristics of steels and lubricants. The abrasive wear of 40KhFA steel was minimum if it was lubricated with Limol + 10% copper powder. In this case, its wear was smaller by a factor of 10, 2, 1.25, and 7.25 as compared with lubricant compositions 1–4, respectively. In the course of minimum wear of 40KhFA steel, in the surface friction layers, we observed the minimum values of second-kind distortions (a/a) and of the true size of domains of X-ray coherent scattering (D) as well as the minimum difference between the crystal lattice constants (a) of steel before and after friction.  相似文献   

2.
The spin hydrodynamic equations for superfluid3He-B have been obtained for the case of external, time-dependent fields. On the basis of a microscopic approach, expressions are found for additional terms in equations containing these fields. Considering the linear response of the system to the switching on of external fields, formulas are found for suitable Green's functions (magnetization-magnetization, rotation-rotation, magnetization-rotation, rotation-magnetization). The rotation-rotation Green's function has the 1/q 2 singularity characteristic of superfluid systems. Connections between Green's functions lead to relations among kinetic coefficients v, 1, and 2. It is also shown that there is a conserved quantityQ (B) = div v s (B) that describes sources or magnetic type charges (monopoles) of the superfluid velocity v s (B) . Comparison with the phenomenological approach suggests thatQ (B) is proportional to a pseudoscalar giving the projection of the spin density onto the vector describing the axis of rotation.  相似文献   

3.
Conclusions The industrial apparatus Omega-2 described above employs an indirect method of measuring the leakage current in the pockets of a silicon matrix with dielectric insulation. The basic error of the apparatus does not exceed 5%.By regulating the voltage applied to the pocket, we would be able to select the structure needed for creating devices with high breakdown voltages and low reverse currents.Translated from Izmeritel'naya Tekhnika, No. 1, pp. 61–62, January, 1979.  相似文献   

4.
Recent and remarkable advances in the experimental study of acoustic scattering from targets immersed in water are leading to a new spectroscopy: resonance acoustic spectroscopy. The discovery and improvement of an intriguing method, the Method of Isolation and Identification of Resonances (MIIR), has made possible experimental determination of the eigenfrequency spectra of aluminum-elastic cylinders and cylindrical shells. This method gives a quasilinear resonance spectra. In addition, it shows the importance of circumferential waves which generate standing waves. They allow us to explain the reradiation of targets after the end of insonification. The MIIR has numerous applications, especially in underwater acoustics and nondestructive testing.  相似文献   

5.
Qantitative analysis of the interrelation of big and little science on the example of Research and Development of higher education in the USA has been made. The difference in the growth rates of big and little science is explained with the help of scientometric index of capital expenditures per researcher. An attempt has been made to compare the dynamics of efficiency of big and little science on the base of mean duration of a research project. Possibilities of an alternative index of a relative amount of preliminary researches (preprojects) are pointed out.  相似文献   

6.
The low-temperature heat release in copper due to ortho-para conversion in hydrogen bubbles is investigated. Deviations from a model of free solid hydrogen are observed: a more intense heat release atT10 K and a rapid (10 h) heat release after cooling to 1.3 K. The experimental results can be explained by the assumption of autocatalytic conversion in the bulk and the catalytic influence of the bubble surface.  相似文献   

7.
The structure and strength of martensite in near titanium alloys have been studied in the composition range (wt %) up to 10% Zr, 6%, Al, 1/2% Mo, 2.4% Si. [0001], 1/3 11¯20 dislocations, 1/3 10¯10 stacking faults and approximately {10¯11} twin related martensite plates are found to be common features of the martensite. Martensite midribs consist either of finely transformed material between martensite plates, or regions of low dislocation density within martensite plates.The martensite morphology is related to the alloy composition, changing from massive to plate-like with increasing solute content. The strength of the martensite is controlled largely by solid solution strengthening.  相似文献   

8.
The present paper reports the extent to which the size and shape of oxide crystallites resulting from a decomposition reaction depend on the crystallite size of the initial material. If those sizes are sufficiently large i.e. higher than critical sizes, the resulting oxide crystallites assume exactly these critical sizes. They are the maximum size that can be reached by oxide crystallites in the absence of any evolution process such as ageing or sintering and are specific to a particular shape of these crystals, which is independent of initial crystallite size. Alternatively, if the initial material crystals are below these critical sizes, at least in one direction, then the dimensions and shape of the oxide crystallites depend on the size of the initial crystallites. These results were interpreted within the framework of the structural conversion mechanism related to the decomposition reaction and showing great similarities with a shear transformation.  相似文献   

9.
The analysis of scientometric matrices for policy implications   总被引:3,自引:1,他引:2  
A method is explained for analysing matrices of statistics where each element should be approximately proportional to some column coefficient and also to some row coefficient. Using U. S. patent data as an example it is shown that entries are usually proportional to country size and patent category size. Deviations from proportionality expectations when tabulated often suggest policy implications.  相似文献   

10.
Results from a comparative analysis of experimental and numerical simulation of the processes of reflection of plane shock waves from concave axisymmetric and two-dimensional surfaces are presented.Academic Scientific Complex The A. V. Luikov Heat and Mass Transfer Institute, Academy of Sciences of Belarus, Minsk. Scientific-Industrial Company Prostor, Moscow Region, Krasnoarmeisk. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 65, No. 5, pp. 548–552, November, 1993.  相似文献   

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