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The experimental data on the normally hemispherical reflectivity of zirconium oxide ceramics are obtained for the wavelength of 0.63 m in the course of the first cycle of heating by concentrated laser radiation up to temperatures above the melting point and free cooling in ambient air. The obtained data are compared with analogous results of the second and subsequent cycles of heating and cooling. Analysis is made of the effect of the temperature field in the heated layer on the reflectivity and on the effective temperature measured by a pyrometer.  相似文献   
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Toward understanding why infant rats ingest high levels of ethanol without initiation procedures, the authors tested effects of mu and kappa receptor antagonists on ethanol reinforcement in neonatal rats. After an intracisternal injection of CTOP (mu antagonist), nor-Binaltorphimine (kappa antagonist), or saline, newborn (3-hr-old) rats were given conditioning pairings of an odor with intraorally infused ethanol or a surrogate nipple with ethanol administered intraperitoneally (to minimize ethanol's gustatory attributes). In each case, these opioid antagonists reduced or eliminated ethanol's reinforcement effect. The same effects occurred with saccharin as the reinforcer in olfactory conditioning. The results imply that activation of mu and kappa receptors, apparently acting jointly, is necessary for reinforcement or that antagonists of this activity impair basic conditioning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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At present, hemoglobin concentration and the volume of an erythrocyte can be determined from the intensities of light scattered by an individual cell at fixed angular intervals. This method is used in modern hemoglobin analyzers, but it requires calibration of optical and electronic units by certified particles of known size and refractive index. We describe a method that is based on the parametric solution of an inverse light-scattering problem and does not require a calibration procedure. The method is based on the use of parameters of the entire angular light-scattering pattern, called an indicatrix here. These parameters do not depend on the absolute intensity of light scattering. The indicatrix parameters form approximating equations that relate these parameters to the size and the phase-shift parameters of the particle. The applicability of the method is demonstrated by measurement of the indicatrices of individual sphered erythrocytes. The indicatrices of the individual erythrocytes were measured with a scanning flow cytometer at an angular range of from 15 to 55 deg. The volume and the hemoglobin concentration have been calculated by use of the developed method and by fitting of the experimental indicatrices to the indicatrices calculated from the Mie theory.  相似文献   
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Using a 150-mum-thick CsLiB(6)O(10) crystal, we produced 100-fs, >200-nJ light pulses tunable between 175 and 180 nm by sum-frequency generation at a 1-kHz repetition rate with an all-solid-state laser system mixing the fourth harmonic of a femtosecond Ti:sapphire regenerative amplifier and the idler pulse from a traveling-wave optical parametric amplifier.  相似文献   
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Difficulties of diagnosis of pleural neoplasms in biopsies are discussed. The short history of serous tumors as entity, their classification, methodological approaches to their morphological diagnosis are outlined. It is concluded that the problem of neoplastic pleural diseases verification can be solved by clinical and morphological correlations. Histochemistry, immunomorphology, and electron microscopy should be combined with conventional morphologic methods used in biopsy investigations.  相似文献   
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