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Computer simulations have shown that the energy of an ultrasonic pulse transmitted through a thin liquid layer is almost independent
of the layer thickness over a relatively wide range. 相似文献
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85.
V. L. Arbuzov B. N. Goshchitskii S. E. Danilov A. V. Kozlov V. D. Parkhomenko N. L. Pecherkina V. V. Sagaradze 《The Physics of Metals and Metallography》2017,118(5):507-515
Complex investigations have been carried out of the radiation damage of nickel alloys microalloyed with interstitial carbon and boron impurities under cascadeless electron and cascade neutron irradiation. Boron’s contribution to the resistivity has been found and the binding energy of a vacancy with boron atom has been determined to be 0.2 eV. The main mechanisms of radiation-induced structural and phase changes have been revealed. 相似文献
86.
The passage of laser radiation through a scattering medium is studied experimentally. A method of determining the optical
characteristics of a scattering media is proposed. The method is based on the measurements of time distributions of the intensity
of ultrashort laser pulses for two layer thicknesses of the medium to be studied. The measurements are carried out with the
use of a single-photon counting system. The proposed method is used to determine the absorption and scattering coefficients
of a model medium from the experimental data. 相似文献
87.
Studies have shown a connection between the individual personality of the user and the way he or she behaves on line. Today many millions of people around the world are connected by being members of various Internet social networks. Ross et al. (2009) studied the connection between the personality of the individual users and their behavior on a social network. They based their study on the self-reports of users of Facebook, one of the most popular social networks, and measured five personality factors using the NEO-PI-R (Costa & McCrae, 1992) questionnaire. They found that while there was a connection between the personalities of surfers and their behavior on Facebook, it was not strong. This study is based on that of Ross et al. (2009), but in our study the self-reports of subjects, were replaced by more objective criteria, measurements of the user-information upload on Facebook. A strong connection was found between personality and Facebook behavior. Implications of the results are discussed. 相似文献
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F. I. Danilov V. S. Protsenko V. O. Gordiienko A. S. Baskevich V. V. Artemchuk 《Protection of Metals and Physical Chemistry of Surfaces》2012,48(3):328-333
The effect of the parameters of pulsed electrolysis on the current efficiency, nanocrystal size, composition, hardness, friction
coefficient, and wear resistance of nanocrystalline Cr-C coatings obtained from electrolyte based on Cr(III) sulfate containing
carbamide and formic acid is studied. It is shown that coatings contain ∼9 wt % of carbon; the current density and pulse ratio
produce practically no effect on their composition. It is found that a maximum appears on the dependence of current efficiency
on pulse ratio in the case of the pulse ratio of ∼1.05–1.1. Thereby, current efficiency greatly exceeds the value implemented
in the steady-state current mode. It is shown that, if the microhardness of Cr-C deposits obtained at constant current is
close to 850–900 HV, the microhardness may increase to ∼1200−300 HV when pulsed electrolysis is used in certain modes. It
is found that application of pulsed electrolysis allows a significant decrease in the friction coefficient of chromium-carbon
coating (steel counterbody) both under the dry friction conditions and in the case of boundary lubrication and also results
in an increase in the deposit wear resistance. 相似文献
90.
One of the most vociferous criticisms of the Internet has always been that it contributes to loneliness among its users. This study analyses results from the World Internet Project, comprised of representative samples from 13 countries (22,002 participants). Thus creating an exceptional international representative sample. In analyzing those results, we argue that in order to achieve a comprehensive understanding of the Internet’s influence over individuals’ social lives; it is essential to consider the different types of social connections that might be influenced by the Internet. We assess the influence of Internet use over social interactions in separate life domains (e.g. with family members; friends; colleagues). Our analysis confirms that Internet usage can actually enhance the social lives of its users. Qualifications to the research are discussed while highlighting the different life domains in which we found significant correlations between Internet usage and increased social interactions. 相似文献