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991.
S Watanabe R R Anderson S Brorson G Dalickas J G Fujimoto T J Flotte 《Photochemistry and photobiology》1991,53(6):757-762
Threshold radiant exposures for grossly apparent immediate whitening and ultrastructural alterations of melanosomes in black guinea pig skin were determined for a series of red visible laser pulses ranging from 4 x 10(-4) to 6.5 x 10(-14) s. Threshold exposures for melanosomal injury were found to be independent of pulsewidth when the pulsewidths were below the estimated thermal relaxation time of melanosomes. Threshold radiant exposures for melanosomal injury were found to increase when the pulsewidths were approximately equal to or above the thermal relaxation time of melanosomes. At longer pulse durations, fracturing of melanosomes was not observed despite the longer exposures necessary for injury. Instead, perimelanosomal vacuoles were noted. These findings are consistent with the theory of selective photothermolysis and provide evidence for the thermal initiation of melanosomal disruption. 相似文献
992.
G. P. Klimov 《Applied Mathematics Letters》1991,4(6):95-97
Let F be a non-arithmetic distribution on the line
, and W be the class of bounded functions w without discontinuity of the second kind such that .In this paper, we show that the solution of the homogeneous renewal equation w = w F in the class W is a constant-function. 相似文献
993.
994.
995.
996.
This paper deals with a computational analysis of the influence of the pressing method and part geometry on the final density
distribution in the cold compaction process of ceramic alumina powders. The analysis is based on the explicit finite-element
model proposed and validated in a previous study. The mechanical behavior of the processing material is described using a
multisurface elastoplastic model, the modified Drucker-Prager/Cap model
Published in Prikladnaya Mekhanika, Vol. 43, No. 10, pp. 129–134, October 2007. 相似文献
997.
Matthew D. Horton 《Linear algebra and its applications》2007,425(1):130-142
After defining and exploring some of the properties of Ihara zeta functions of digraphs, we improve upon Kotani and Sunada’s bounds on the poles of Ihara zeta functions of undirected graphs by considering digraphs whose adjacency matrices are directed edge matrices. 相似文献
998.
Günter F. Steinke 《Journal of Geometry》2007,87(1-2):160-178
999.
1000.
A. Puiu G. Giubileo G. Addolorato L. Revelli G. Gasbarrini R. Bellantone A. D’Amore C. P. Lombardi C. Carrozza 《Laser Physics》2007,17(4):448-452
Nowadays, there is high demand for sensitive gas sensors both for human and environmental monitoring. This paper deals with a high-resolution (0.2 ppb) laser-based photoacoustic spectroscopic system realized at ENEA Frascati, Italy, applied for monitoring stress in scuba divers during sustained immersion by analyzing breath samples. Blood tests and psychometric tests for scuba divers were performed at Catholic University in Rome. Results will be reported and discussed. 相似文献