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61.
V. A. Ogorodnikov A. G. Ivanov V. I. Luchinin A. A. Khokhlov A. P. Tsoi 《Combustion, Explosion, and Shock Waves》1993,29(6):750-754
Experimental results on the spall strength of copper in which the scale of the system was changed by a factor of ten show
that the scale effect for high-rate one-dimensional strain depends on energy. The spall energy per unit surface area for failure
increases with time.
Arzamas-16. Translated from Fizika Goreniya i Vzryva, Vol. 29, No. 6, pp. 88–93, November–December, 1993. 相似文献
62.
Kabanov Alexander V.; Klyachko Natalya L.; Nametkin Sergei N.; Merker Steffen; Zaroza Anna V.; Bunik Vita I.; Ivanov Mikhail V.; Levashov Andrey V. 《Protein engineering, design & selection : PEDS》1991,4(8):1009-1017
The size of the inner water cavity of reversed micelles formedin a triple system water-surfactant-organic solventcan be widely varied by changing the degree of surfactant hydration.This gives grounds to use reversed micelles as matrix microreactorsfor the design of supramolecular complexes of proteins. Usingultracentrifugation analysis, it has been demonstrated thatthe oligomeric composition of various enzymes (ketoglutaratedehydrogenase, alkaline phosphatase, lactic dehydrogenase, glyceraldehyde-3-phosphatedehydrogenase) solubilized in reversed micelles of Aerosol OT[sodium bis(2-ethylehexyl)sulfosuccinate] in octane changesupon variation of the degree of hydration. An oligomeric complexforms under conditions when the radius of the micelle innercavity is big enough to incorporate this complex as a whole.At lower degrees of hydration the micelles uncouplesuch complexes to their components. The catalytic propertiesof various oligomeric complexes have been studied. Possibilitiesof using reversed micelles for the separation of subunits ofoligomeric enzymes under non-denaturating conditions have beendemonstrated. In particular, the isolated subunits of alkalinephosphatase, lactic dehydrogenase and glyceralde-hyde-3-phosphatedehydrogenase have been found to be active in Aerosol OT reversedmicelles. The dependences of the catalytic activity of oligomericenzymes represent saw-like curves. The maxima of the catalyticactivity observed at these curves relate to the functioningof various oligomeric forms of an enzyme. The radii of the micelleinner cavity under conditions when these maxima are observedcorrelate with the linear dimensions of the enzyme oligomericforms. Correlation of the position of a maximum with the shapeof an oligomeric complex is discussed. 相似文献
63.
64.
Pavel P. Fedorov Alexander A. Alexandrov Valery V. Voronov Mariya N. Mayakova Alexander E. Baranchikov Vladimir K. Ivanov 《Journal of the American Ceramic Society》2021,104(6):2836-2848
Phase formation in the SrF2–LaF3 system was studied at temperatures ranging from 300°C to 450°C using nitrate flux. The solubility of LaF3 in SrF2 decreases with decreasing temperature. The equilibrium width of the solid solution region Sr1−xLaxF2+x at 400°C, it is 44.6 ± 0.4 mol% LaF3 (x = 0.446), at 350°C — 38.3 ± 0.7 mol% LaF3 (x = 0.383), and decreases almost to zero at 300°C. 相似文献
65.
V. Yu. Vasil''ev T. K. Sergeeva Yu. V. Baldokhin E. S. Ivanov V. V. Novosadov V. Ya. Bayankin 《Protection of Metals》2002,38(2):166-171
The results of field tests carried out at main gas pipelines (MP) are shown. The distribution of internal stresses along the MP perimeter is obtained. Polarization currents at differently strained pipeline fragments are determined in soils taken at different distances from the failure epicenter. The mechanoelectrochemical effect is shown to be twice greater in failure soils. Its value can serve as a criterion of the stress corrosion probability. 相似文献
66.
67.
Conclusions
Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 6, pp. 13–16, June, 1999. 相似文献
1. | Low-carbon martensitic steels such as 10N3M1.5B can be coated by single-phase boride layers with a low brittleness by a conventional boronizing. |
2. | Boronizing by low-carbon martensitic steels from daubs at 910°C for 3 h with cooling in air gives a martensitic structure in the bulk of the part. |
3. | Chromium alloying of a martensitic steel causes the formation of a brittle FeB boride in the boronized coat. |
4. | The introduction of copper oxide into the slip daub makes it possible to control the phase composition and the structure of the boride layer on low-carbon martensitic steels. |
68.
A. P. Ivanov A. N. Kudinov D. Yu. Lebedev V. P. Tsvetkov I. V. Tsvetkov 《Mathematical Models and Computer Simulations》2016,8(1):7-18
For the specific analysis of the variability of RR intervals of the cardiac rhythm, a method for measuring the instantaneous cardiac rhythm (ICR) represented by a multifractal dynamical model (MDM) has been developed. The advantages of this method, compared to the statistical methods of analysis of the RR intervals used, have been demonstrated. The method allows possible catastrophes of the cardiovascular system to be predicted. Using the data of Holter monitoring and the program system developed, we have plotted ICR curves, an ICR piecewise linear trend, and variability charts for three randomly chosen time intervals. The self-similarity (fractality) of the ICR up to an accuracy of 5% has been shown based on the explicit data. The MDM parameters have been calculated based on the ICR data. The analysis of the dynamics of these parameters has been conducted and their compliance with the status of the patient examined has been studied. The relevance of the ICR examination within MDM is closely related to the necessity of recognizing new markers of adverse cardiovascular episodes. The research performed shows that the results obtained could be taken as a basis for developing a new mathematical method of ICR examination based on Holter monitoring. 相似文献
69.
Dianne Cyr Milena Head Alex Ivanov 《International journal of human-computer studies》2009,67(10):850-869
Novel applications of website interactivity are important to attract and retain online users. In this empirical study five designs for interactivity are examined using different web-poll interfaces. The goal of the investigation is to examine perceived interactivity in a model which includes most commonly tested cognitive elements such as efficiency and effectiveness, but augments this model with the inclusion of a cognitive–affective element for trust, and an affective element of enjoyment. More specifically, a model is created to validate the relationship of perceived interactivity (comprised of user control, user connectedness, and responsiveness of the web-poll application) to efficiency, effectiveness, trust and enjoyment, of the website. In turn, efficiency, effectiveness, trust, and enjoyment are tested for their influence on user behavioral intentions for e-loyalty. All relationships in the model are supported. In addition, exploratory evaluation of qualitative comments is conducted to investigate additional insights between the five web-poll treatments in this investigation. The research confirms the complexity of a model in which cognitive, cognitive–affective and affective elements are present, and advances knowledge on the consequences of perceived interactivity. In additional to theoretical advancements, the research has merit for web designers and online marketers regarding how to enhance interactive online web applications. 相似文献
70.
N. I. Boyko L. S. Evdoshenko A. I. Zarochentsev V. M. Ivanov V. G. Artyukh 《Instruments and Experimental Techniques》2008,51(1):70-77
A series of four-channel trigatrons operating at a voltage of up to 400 kV and a current of 280 kA per channel have been developed and tested. The control electrode is coaxially arranged in a hole of the main (positive) high-voltage electrode. This design ensures a small spread (jitter) of the operation delay time (Δt d < 1 ns) for the discharge gap filled with elegas (SF6). The electric strength of lateral surfaces of the device body is increased without using dielectric fluids. The service life of switches is increased by using tubular metal (steel) screens in the working volume. For the parallel operation of trigatrons, the Δt d value is also below 1 ns, but it sharply increases if the gap between the main electrodes exceeds 11–12 mm. 相似文献