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861.
We study the conjugate boundary-value problem with boundary conditions whose orders can be as large as the order of the differential equation or larger. We construct the Green's function of the problem over the entire space when the separating surface is a hyperplane, and we describe its properties. Bibliography: 6 titles.Translated fromMatematicheskie Metody i Fiziko-Mekhanicheskie Polya, Issue 30, 1989, pp. 20–24. 相似文献
862.
The microwave subsidiary absorption threshold in tangentially magnetized yttrium-iron-garnet (YIG) films was measured as a function of the static magnetic field, film thickness and decrease in the 0.3–3 μm range is observed. The effect is explained quantitatively by using modified Damon-Eshbach dispersion relations which take into account exchange interactions.
The effect of temperature on hcrit, the smallest threshold field amplitude, in the 250<T< 450 K temperature range can be expressed by an empirical relationship hcrit Ms(T)-1.6 where Ms is the saturation magnetization. This hcrit vs Ms relationship is similar to that obtained for the magnetization dependence of parallel pump thresholds in Li-Ti ferrite compounds. 相似文献
863.
864.
865.
Ulenikov O. N. Tolchenov R. N. Melekhina E. N. Koivusaari M. Alanko S. Anttila R. 《Journal of Molecular Spectroscopy》1995,170(2)
High resolution Fourier transform spectra of deuterated hydrogen sulfide have been recorded in the region 2400-3000 cm−1. Rotational structures of the ν1 + ν2, ν2 + ν3 bands of D232S, of the ν3 and ν1 + ν2 bands of HD32S, and of the ν1 + ν2 band of HD34S were analyzed. Band centers and rotational, centrifugal distortion, and resonance parameters were obtained, which reproduce the initial values of the upper energy levels within a mean accuracy of 1.39 × 10−4 cm−1 for the states (110) and (011) of D232S, 1.61 × 10−4 cm−1 and 1.82 × 10−4 cm−1 for the states (001) and (110) of HD32S, and 2.09 × 10−4 cm−1 for the state (110) of HD34S, respectively. 相似文献
866.
V. S. Kirilyuk 《Journal of Mathematical Sciences》1995,77(6):3486-3488
We consider an elastic isotropic material containing a fibrous inclusion or a void subject to loads. We study the possibility
of increasing the strength of the material using “control action.” As examples of such actions we consider an additional external
load, application of pressure in the cavities (voids), and variation of the temperature of uniform heating of the medium with
the inclusions. Studies are carried out for two-dimensional problems of linear elasticity theory. From the class of all possible
actions we single out a subclass leading to states of equal strength along the phase interface. We study the efficiency of
these types of action and show that in certain cases they lead to a manifold increase in the strength of the material. We
give the results of numerical studies.
Translated fromTeoreticheskaya i Prikladnaya Mekhanika, No. 24, 1993, pp. 15–19. 相似文献
867.
Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, No. 4, pp. 108–112, July–August, 1993. 相似文献
868.
869.
V. O. Kur'yanov T. F. Zhelobetskaya A. E. Zemlyakov V. Ya. Chirva 《Chemistry of Natural Compounds》1993,29(1):103-106
The synthesis has been effected of derivatives of MDP having a spacer with an amino or carboxy group. The final stage of the synthesis was the condensation of Boc-L-Ala-D-iGln with 6-aminohexanol (followed by the two-stage replacement of the hydroxy by an azido group) or with benzyl 6-aminohexanoate.Simferopol' State University. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 122–125, January–February, 1993. 相似文献
870.
A PULSED LASER AND PULSE RADIOLYSIS STUDY OF AMPHIPHILIC CHLOROPHYLL DERIVATIVES WITH PDT ACTIVITY TOWARD MALIGNANT MELANOMA 总被引:1,自引:0,他引:1
L. Fiedor A. A. Gorman I. Hamblett V. Rosenbach-Belkin Y. Salomon A. Scherz I. Tregub 《Photochemistry and photobiology》1993,58(4):506-511
Two amphiphilic derivatives of chlorophyll, which have high potential as photodynamic therapy sensitizers for malignant melanoma have been investigated by a combination of laser flash photolysis and pulse radiolysis. It is shown that direct excitation of monomeric forms of these molecules in both hydrophilic and hydrophobic environments produces significant yields of the corresponding triplet states, which have been characterized in terms of spectral and kinetic parameters. In both environments, scavenging of the triplets by oxygen produces singlet oxygen, O2 (l Δ8 ), with essentially unit efficiency as evidenced by time-resolved IR luminescence measurements. 相似文献