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991.
Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, No. 4, pp. 108–112, July–August, 1993. 相似文献
992.
993.
ALEPH Collaboration D. Buskulic D. Casper I. De Bonis D. Decamp P. Ghez C. Goy J. -P. Lees A. Lucotte M. -N. Minard et al. 《Zeitschrift fur Physik C Particles and Fields》1995,69(1):379-392
A data sample of about 3.0 million hadronicZ decays collected by the ALEPH experiment at LEP in the years 1991 through 1994 is used to make an inclusive selection of
B hadron events. In this event sample 4227±140±252B* mesons in the decayB*→Bγ and 1944±108±161B**
u,d
mesons decaying into a B meson and a charged pion are reconstructed. Here and in the followingB**
u,d
denotes the eightL=1(bū) and (bd) states and their charge conjugate.
For the well establishedB* meson the following quantities are obtained:ΔM=M
B*−MB=(45.30±0.35±0.87) MeV/c2 andN
B*/(N
B+N
B*)=(77.1±2.6±7.0)%. The angular distribution of the photons in theB* rest frame is used to measure the relative contribution of longitudinalB* polarization states to beσ
L/(σ
L+σ
T)=(33±6±5)%. 相似文献
994.
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
995.
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
996.
O. A. Rakitin E. A. Khaibullina T. I. Godovikova V. A. Ogurtsov L. I. Khimel'nitskii 《Chemistry of Heterocyclic Compounds》1993,29(8):952-954
Previously unreported furoxanenitrolic acids have been synthesized.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1117–1119, August, 1993. 相似文献
997.
Published in Teoreticheskaya i Matematicheskaya Fizika, Vol. 95, No. 2, pp. 183–186, May, 1993. 相似文献
998.
In M-ary, Gray coded frequency shift keying with limiter discriminator detection the bit error probability is usually approximated by the symbol error probability divided by the number of bits in a symbol. This approximation is known to be excellent for phase shift keying with large energy-to-noise ratios and Gaussian channel. In other cases this may be questionable. The authors compute the exact values of bit error probability as a function of energy-to-noise-ratio per bit for Gaussian, Rayleigh and Rician channels. They also compute the relative error involved in this approximation 相似文献
999.
Wideband chirp measurement technique for high bit rate sources 总被引:1,自引:0,他引:1
A Mach Zehnder (MZ) interferometer has been used as an optical discriminator to measure the time-resolved frequency chirp of an optical source 相似文献
1000.
Modeling and numerical simulations of the convective flows induced by the vibration of the monocrystal during crystal growth have been performed for two configurations simulating the Cz and FZ methods. This permitted to emphasize the role of different vibrational mechanisms in the formation of the average flows. It is shown that an appropriate combination of these mechanisms can be used to counteract the usual convective flows (buoyancy- and/or thermocapillary-driven) inherent to crystal growth processes from the liquid phase. While vibrational convection is rather complex due to these identified mechanisms, the new modeling used in the present paper opens up very promising perspectives to efficiently control heat and mass transfer during real industrial applications of crystal growth from the liquid phase. 相似文献