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41.
Three new cytotoxic polyacetylenes, PQ-1 (1), PQ-2 (2) and PQ-3 (3), have been isolated from Panax quinquefolium. The structures of these acetylenes were determined by analyses of their 1H-1H and 1H-13C COSY spectra. All these compounds exhibited strong cytotoxic activities against leukemia cells (L 1210) in tissue culture. 相似文献
42.
A. R. Volkov B. V. Shul'gin T. I. Polupanova V. N. Lebedev A. A. Nagornyi V. L. Petrov Yu. F. Kargin 《Journal of Applied Spectroscopy》1991,54(6):585-590
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 54, No. 6, pp. 970–975, June, 1991. 相似文献
43.
A. N. Troflmchuk 《Journal of Mathematical Sciences》1991,57(5):3407-3409
We develop a method of computing the nonsteady-state and free oscillations of a framed elastic structure situated on an elastic base and containing an ideal compressible fluid. The solution uses the method of integral transforms in conjunction with the method of orthogonal polynomials. In the transform space the problem reduces to systems of linear algebraic equations. The Fourier transform is applied to return to the original space. Examples of the computation are given.Translated fromDinamicheskie Sistemy, No. 6, 1987, pp. 69–72. 相似文献
44.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 51, No. 2, pp. 212–217, August, 1989. 相似文献
45.
The tape stripping technique is an experimental method frequently used for reconstruction of the in-depth distribution of various topically administered substances within the horny layer of human skin, e.g., compounds contained in sunscreens. Titanium dioxide (TiO2) nanoparticles (25–200 nm in diameter) are one such compound. Optical techniques which apply blue light are found to be suitable for reconstruction. However, the presence of particles affects the light propagation within the skin and therefore causes incorrect determination of strip thickness, leading to an improper reconstructed distribution of nanoparticle concentration revealed from the experimental data. This study evaluates the errors emerging from the use of blue (400 nm) and NIR (800 nm) radiation and finds the use of longer wavelength light more advantageous. Particles of different diameters are considered, and it is revealed that the application of small particles (25–60 nm) results in the lowest rate of error. 相似文献
46.
N. N. Manuylov 《Journal of Mathematical Sciences》2006,133(6):1686-1692
Renormalization formulas connecting the points of the orbits O
0
±
, i.e., the sequences generated by an irrational shift on the half-open interval [0, 1) or (0, 1], and the points of the orbits'
derivatives dmO
0
±
, i.e., the sequences obtained by restricting O
0
±
to half-open intervals of smaller length, are obtained. Bibliography: 5 titles.
__________
Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 314, 2004, pp. 142–154. 相似文献
47.
S. N. Solov’ev K. A. Minasyan A. A. Korunov 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2006,80(4):663-664
The enthalpies of reactions of La2CoO4(cr) and CoCl2(cr) with hydrochloric acid were measured with an isothermal-jacket calorimeter. The results obtained and the available literature data were used to calculate the standard enthalpy of formation of La2CoO4(cr) at 298.15 K, Δf H o = ?2179 ± 7 kJ/mol. 相似文献
48.
A noiselike fine structure of ferromagnetic resonance spectra in magnetic powders was investigated after ultrasonic treatment. Magnetic interactions between particles are proved to have an influence upon the fine structure formation. After decreasing dipole-dipole magnetic interactions in dilute suspension a special order appears in fine-structure spectra, which is generally the same for different systems. 相似文献
49.
50.
An overview of theoretical and experimental studies of the coherent type-B e
+
e-pair production by photons in aligned crystals performed at Nuclear Physics Institute at Tomsk Polytechnic University is given. 相似文献