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71.
In this paper it has been experimentally proved that the dislocation density of annealed copper ribbons grows up to saturation during repeated quenching. The effect is explained on the basis of a simple idea: During each annealing a certain part of the excessive dislocation density is removed and during each quenching a constant increase in dislocation density is generated. 相似文献
72.
In the great majority of papers dealing with non-linear dynamic buckling of plates it is assumed that the edge at which the in-plane load is applied is not deformable (rigid). In those few references in which buckling with deformable edges is examined normally a variational approach is used, based on “trial” functions for the in-plane displacements, which approach often leads to incorrect results. In this paper an exact form of the solution is found for the in-plane displacements, it being assumed that the membrane force is, at all times, exactly equal to the load applied at the corresponding loaded edge. As is well known, when the plate is buckled through a rigid beam these two forces are only on average equal to each other. It is shown here that the deformability of the loaded edges for plates undergoing large deformations should be taken into account for square-shaped plates, especially for those close to the so-called “golden-cut” shape (the aspect ratio between the edges equal to √2), while for long rectangular plates this effect may be disregarded. 相似文献
73.
In the reaction of N-[2-(5-bromouracil-1-yl)ethyl]alkylamines with alkylamines at 40 °C kine-substitution takes place with the formation of N-[2-(6-alkylamino-uracil-1-yl)ethyl]alkylamines.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1260–1261, September, 1984. 相似文献
74.
The magnetostriction constant of three iron-nickel alloys and one Fe-Ni-Co alloy was measured as a function of the plastic elongation up to about 25%. The magnetostriction constant decreases with deformation in all materials. In Fe-Ni-Co alloy the volume magnetostriction also decreases. The influence of crystallographic texture is discussed and it is shown that it is not a decisive factor. The observed decrease is explained by assuming the influence of lattice deformation on spin-orbital interaction.
In conclusion the authors thank Z. Málek and S. Libovický for carefully reading this paper and for remarks, J. Míová for help in the measurements, J. Cáslavský for X-ray determination of the texture and members of the chemical department of the Institute of Physics for thermal treatment and analysis of the samples. 相似文献
-
- Fe-Ni-Co 25%. . Fe-Ni-Co . , . .
In conclusion the authors thank Z. Málek and S. Libovický for carefully reading this paper and for remarks, J. Míová for help in the measurements, J. Cáslavský for X-ray determination of the texture and members of the chemical department of the Institute of Physics for thermal treatment and analysis of the samples. 相似文献
75.
76.
A direct spectrophotometric method has been developed for the determination of the amount of proteins immobilized on bead cellulose. The method is based on dissolution of conjugates in cadmium tris(ethylenediamine) hydroxide (trivial name, cadoxene) that is optically transparent in the region of the UV spectrum in which proteins absorb. The method developed for the determination of immobilized proteins is simple, rapid, and readily reproducible. The sensitivity of the method is dependent on theA 1cm 1% value of the free protein and on the amount of bound proteinm (mg protein/g carrier). In the terms ofA 1cm 1% ≥25 andm≥120 mg/g, the sensitivity of the mentioned method was comparable with those obtained by amino acids analyses by the ninhydrin reaction, by the modified Lowry reaction, or by radiometric determination. The possibility of substituting the direct spectrophotometric method for amino acid analysis was statistically evaluated; it does not seem to be rejected at the highest level of significance,P≤1%. The differences in paired observations were significant, but nonetheless proportional over the whole range of protein concentrations, making both methods correlable. The absolute accuracy of the direct spectrophotometric method could be influenced by the change ofA 1cm 1% value during solvolysis of the conjugate in cadoxene. 相似文献
77.
M. Yu. Lidak R. A. Paégle V. É. Straume D. É. Shnore Yu. P. Shvachkin 《Chemistry of Heterocyclic Compounds》1970,6(7):934-935
One of the types of pyurinylpeptides (i.e., peptides constructed of pyrimidyl-and purinyl--amino acids) consists of peptides including residues of only those -amino acids the lateral radicals of which contain nucleic bases. Below, such amino acids will be called nucleoamino acids and the peptides derived from them nucleopeptides. The latter are hybrid analogs of nucleic acids and proteins. Their study may lead to important theoretical and practical results.Translated from Khimiya Geterotsiklicheskikh Soedinenii, Vol. 6, No. 7,pp. 1002–1003, July, 1970.We are continuing the synthesis and study of the properties of the pyurinylpeptides and nucleopeptides. 相似文献
78.
79.
Jaroslav Pačes 《Czechoslovak Journal of Physics》1957,7(6):729-743
. - II- . . 相似文献
80.
We investigate the collective mode dispersions for the tight-binding dielectric matrix with two one-dimensional electron bands
per donor and acceptor chains, and the three-dimensional long-range Coulomb electron-electron interaction within the random
phase approximation. The hybridized collective modes are the result of the strong coupling between the intraband plasmon and
the interband dipolar modes due to strong dipole Coulomb interactions. Our calculations show the existence of the low-energy
renormalized plasmon mode above the electron-hole quasi-continuum in the long wavelength limit. The obtained modes are brought
into correspondence with the optical data of quasi-one-dimensional organic conductor tetrathiafulvalene-tetracyanoquinodimethane
(TTF-TCNQ). Namely, the renormalized plasmon and the dipolar mode are assigned to the observed excitations at respective energy
scales of roughly 10 meV and 0.75 eV, explaining why lower excitation is eliminated while higher excitation persists below
the temperature of the Peierls phase transition. 相似文献