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A dynamical scheme for composite quarks and leptons is proposed in which the observed fermions are Goldstone particles of spontaneously broken supersymmetry. Their residual interactions are described by a minimal effective lagrangian which invokes a non-linear realization of sypersymmetry. Possible experimental consequences are studied and it is found that the most conspicuous signature of this scheme would be a dramatic increase in the lepton pair production in hadronic collisions, particularly in scattering, at high energy. 相似文献
875.
Ivan Šoštarić Doz. Dr. Vladimir Simeon 《Monatshefte für Chemie / Chemical Monthly》1975,106(1):169-173
Stability constants of cobalt(II) and copper(II) complexes with α-, β-, and γ-aminobutyrate as well as the protonation constants of these ligands have been determined by potentiometric titration. ΔG ? values, computed from the stability constants, increase in the orderAABA. The increase in ΔG ? AABA→BABA amounts approx. 15 per cent. The same difference was observed for α- and β-alaninato complexes with various transition metal ions. 相似文献
876.
G. V. Vinogradov Yu. Yanovsky A. I. Isayev 《Journal of Polymer Science.Polymer Physics》1970,8(8):1239-1259
The influence of periodic shear deformation and steady flow on a typical amorphous polymer is discussed. Forced sinusoidal vibrations were applied and the complex viscosity was determined. The action of a vibration of finite amplitude is equivalent to steady flow with a definite finite shear rate. Both processes cause truncation of the long-time part of the relaxation specturm. It may be accepted to a first approximation that the long-time boundary of the remaining part of the relaxation spectrum conforms to the long-time part of the initial spectrum, even if the plateau region of the spectrum is truncated. The concept of limiting truncation of the short-time part of the spectrum is introduced, this corresponding to the minimum absolute value of the complex viscosity versus reduced frequency and the lowest values of the dynamic and apparent viscosities. With an approximate representation of the relaxation spectrum, calculations were made of the maximum values of the viscosity and the coefficient relating the first difference of normal stresses to the square of the shear rate, and also of the apparent viscosity and normal stresses as functions of the shear rate. The calculated values are compared with experimental measurements, and it is shown that the correlation of the apparent viscosity and the absolute value of the complex viscosity is distributed at high frequencies, being superseded by a correlation between the apparent and dynamic viscosities. 相似文献
877.
V. V. Korshak I. A. Gribova A. V. Vinogradov Ya. V. Genin A. P. Krasnov D. Ya. Tsvankin B. V. Lokshin G. L. Gladyshev I. P. Laputina 《Mechanics of Composite Materials》1976,12(4):581-588
Conclusions 1. The process of friction of antifrictional self-lubricating plastics based on F-1 polyarylate and various fillers has been studied. It has been shown that a distinctive feature of this process is the formation of a film of the same composition as that of the antifrictional plastic on the steel surface.2. It has been shown that during the process of friction of antifrictional self-lubricating plastics both structural changes in the mobybdenum disulfide and also tribochemical transformations of molybdenum disulfide and copper, plus reaction of these with the counterbody material, take place in the surface films.3. It has been found that the nature of the tribochemical transformations depends on the chemical composition of the antifrictional self-lubricating plastic and affects the temperature limits of the friction zones.Institute of Heteroorganic Compounds, Academy of Sciences of the USSR, Moscow. Translated from Mekhanika Polimerov, No. 4, pp. 649–657, July–August, 1976. 相似文献
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