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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.
If f(r) is the number of contributions of an author or rank r, then it is shown that f(r) is proportional to r, where >0. The model is dependent on the definitions of a contribution and rank of an author. Three estimation procedures are illustrated and four other scientific productivity studies and two data sets on Canadian Mathematicians are shown to adequately fit this rank-frequency relationship.Research partially supported by National Research Council Grant No. A9229.  相似文献   

3.
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   

4.
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   

5.
A viewpoint is given, according to which, addivitity may be defined only at the intuition level and quantitative latent variables are origin additive. The proposed solution to the non-additivity problem consists in restricting quantitative indicator scales by the so-called natural, in particular, open scales.  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.
This paper presents an empirical study of the relations between scientific output and collaboration performed on two scales: (1) an individual scale, for members of a study model, and (2) a group scale, for three samples varying in the level of productivity. The rank approach was applied in the preparation of the study model resulting in the selection of a set of the most prolific authors. In the course of that process, multiple authorship problem was solved by a dual approach, consisting of normal count and modified straight count procedures. As shown by the analysis of collaborative patterns, either on individual or on group scales, scientific output is highly dependent on the frequency of collaboration among the same authors. Expressed as the collaboration measure, it might serve as an indicator in comparative analyses of scientific productivity in a given field of science.  相似文献   

8.
The behaviour of different iron salts (FeSO4.7 H2O, FeC2O4.2 H2O, Mohr's salt, and basic iron carbonate) was studied by means of the emanation method, DTA and dilatometry. The salts were heated within the temperature range of 20 to 1100 C, under identical conditions. The results obtained are compared and the process of thermal decomposition of the different salts is discussed.The activity of ferric oxide obtained by decomposition of various iron salts is estimated, and it is suggested that the low activity of the sulphate-derived ferric oxides is related to a low thermal annealing rate, while the higher activities of the other two resultant ferric oxides are similarly related to higher thermal annealing rates.  相似文献   

9.
This article examines volume and weight methods of measuring heat flows from the environment to the structural elements of cooled radiation detectors. The sources and ranges of errors made in the determination of heat flow by these two methods are determined. A theoretical-empirical method is proposed to determine heat flow for a specified ambient temperature and a specified level of the liquid phase of the coolant (including the zero level).  相似文献   

10.
H. Inhaber 《Scientometrics》1984,6(2):103-104
The methodology of the science of science is claimed to be plagued by one-dimensional thinking, and it is urged that a multi-dimensional view be adopted instead. In a one-dimensional model cause is a meaningful word, superlatives can be used, dichotomous thinking is realistic, with a resultant zero-sum mentality, and the make a hypothesis-find a correlation method makes sense. In the multidimensional framework these four characteristics are unsuitable, and instead a quite different set of questions arise as appropriate. This is illustrated on five examples taken from among currently interesting questions in the science of science. Following some remarks about simplicity and about the role and limitations of multiple regression analyses, it is concluded that, among other things, more purely phenomenological studies are needed to make progress in the science of science.  相似文献   

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