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991.
Experimental results for an integrated-optical state-of-polarisation (SOP) controller device on Ti:LiNbO3 for continuous broadband optical operation, with small temperature sensitivity and the possibility of integration with polarisation- insensitive directional couplers, are presented.  相似文献   
992.
A device containing a temperature converter with an infrared camera is described. Its application allows one to instantly measure the temperature field of a gas flow in regions of arbitrary sizes.  相似文献   
993.
The functional of receptor sensitivity of a territory to the disposition of emission sources can adequately be calculated with the use of the mathematical apparatus of adjoint equations. The solutions of these equations allow one to determine the action of pollutants in the form of aerosols or harmful gaseous impurities on the environment and human health. Examples of calculation of the sensitivity functional on the basis of solution of adjoint equations have been presented. Mathematical models for the typical equations on optimum placement of industrial plants have been formulated. An interpretation of the results obtained has been given.  相似文献   
994.
Stability has been examined for an ordered chain of monodisperse droplets under vacuum, which interact one with another via the evaporating molecules.Translated from Inzhenerno-fizicheskii Zhurnal, Vol. 60, No. 4, pp. 656–660, April, 1991.  相似文献   
995.
AC hot-carrier effects in n-MOSFETs with thin (~85 Å) N2O-nitrided gate oxides have been studied and compared with control devices with gate oxides grown in O2. Results show that furnace N2O-nitrided oxide devices exhibit significantly reduced AC-stress-induced degradation. In addition, they show weaker dependences of device degradation on applied gate pulse frequency and pulse width. Results suggest that the improved AC-hot-carrier immunity of the N2O-nitrided oxide device may be due to the significantly suppressed interface state generation and neutral electron trap generation during stressing  相似文献   
996.
The qualitative and quantitative radiochemical composition of liquid wastes is substantiated. This makes possible further safe operation of deep waste disposal sites at the Mining-Chemical Plant and the Siberian Chemical Plant. The toxicity and temperature in a formation with the wastes removed are used as the assessment criteria, satisfaction of which guarantees that the wastes will remain localized within the assigned boundaries of the waste-disposal formation site. It is concluded that the standard limit should be imposed on the specific activity of the long-lived group of radionuclides – 90Sr and 137Cs – rather than on the total specific activity of the wastes placed in deep disposal sites. For maximum specific activity of 90Sr and 137Cs of 37 GBq/dm3 and total specific activity not exceeding 185 GBq/dm3 for buried wastes with radionuclide composition characteristic of modern radiochemical production operations, it is impossible for potentially dangerous radiation and thermochemical processes to occur in the waste-disposal formation site. The recommended limit permits reducing substantially the volume of buried wastes and therefore the region over which the wastes propagate in the deep disposal site.  相似文献   
997.
A novel microwave imaging technique based on the generalised weighted backprojection operator is introduced and tested using experimental data. Images of the internal structure of penetrable objects using this technique are compared and contrasted with images found from the classical back-projection method. It is demonstrated that the new method provides high-quality images of both discrete and continuous internal structure without the distortions characteristic of traditional methods.  相似文献   
998.
The apparent thermal conductivity λ of evacuated SiO2-aerogel tiles was measured with our small guarded hot plate vacuum system LOLA II. In order to study the influence of the boundary emissivity on λ the plates (20 × 20 cm2) were either used with their plasma-sprayed surfaces ( ≈ 0.5) or with low-emissivity aluminum ( ≈ 0.05) foils as covers. The difference in the apparent conductivity already showed at room temperature and rose to about 50% for radiative temperatures Tr = 570 K. An important consequence is that superinsulating SiO2-aerogel systems should always be provided with low-emissivity boundaries around the aerogel. The calorimetric results for λ are compared with radiative conductivity values derived from spectral i.r. transmission measurements.  相似文献   
999.
A failure assessment diagram is derived from carbon-manganese steel compact tension specimens. The diagram has been determined from an elastic-plastic finite element analysis of a compact tension specimen geometry. The diagram has been validated by using experimental fracture toughness data obtained on the same steel and specimen geometry modelled in the finite element analysis. The plastic collapse load has been determined empirically for this geometry.It is shown that a non-work-hardening failure assessment diagram is not a good representation of the experimental data and that the computed failure assessment diagram is more appropriate for describing the behaviour of the carbon-manganese steel specimens.  相似文献   
1000.
In this review we have summarized the iron bioavailability literature dealing with protein (or major dietary protein source) effects and proposed a mechanism for these effects compatible with existing empirical data. Data from studies employing a variety of approaches are fairly consistent in showing that meats enhance non-heme iron absorption while plant, milk and egg proteins depress it. The variable, and sometimes opposite, effects of different proteins on iron bioavailability may be explained by the following proposed mechanism: (1) protein enhances iron bioavailability by releasing peptides during digestion which form soluble, low molecular weight complexes that readily release iron to mucosal receptors; (2) protein depresses iron bioavailability by releasing peptides which form insoluble complexes with iron or which form soluble complexes that do not release iron to mucosal receptors. Data from the literature, including our own evidence, which support the above hypothesis are discussed.  相似文献   
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