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91.
A technique is proposed for injection-seeding control of tunable lasers. It is based on a combination of successive external injection and intracavity self-injection of radiation when the active medium is pumped by dual-step pulses. The technique is tested both experimentally (in the case of Nd:YAG-laser-pumped pulsed dye lasers) and numerically, using a model developed by us. Full conversion of the broadband spectrum into the injected line is achieved for an output energy greater by a factor of about 50 than that managed by means of the traditional injection-seeding technique under identical conditions.  相似文献   
92.
A relationship between the structure and water purifying ability of waste glass prepared from household garbage and Fe2O3 was examined by 57Fe-Mössbauer and induced coupled plasma (ICP) measurements. From the Debye temperature of waste glass, FeII proved to be loosely bound in the glass network as a network modifier. Dissolution amount of FeIII into artificial drain can be controlled from 0.14 to 0.35 mg/l by changing the Fe2O3 content. It proved that chemical oxygen demand (COD) decreases in proportion to the content of FeIII, indicating that iron causes decomposition of organic and phosphorus compounds.  相似文献   
93.
A generalized phase-shift method is developed for automatic measurement of principal-stress directions in the whole field of a model from photoelastic experiments. This method uses a set of light intensities obtained from the rotation of polaroids in dark-field plane polariscopes at each point. To investigate the accuracy of the measurement, time-series light intensity curves with different noise and different numbers of data which constitute the curves are used in computer simulation. The error of the measurement of the principal-stress directions obtained by the method is not greatly affected by noise when the number of data exceeds 50. This method is applied to a circular disk subjected to a concentrated load. The principal-stress directions obtained by the method are found to be in good agreement with the theory.Presented at 1996 International Workshop on Interferometry (IWI ‘96), August 27–29, Saitama, Japan.  相似文献   
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The expression of the electronic specific heat for the symmetric Anderson model is obtained in closed form.  相似文献   
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Plasma temperature obtained with a negative theta-pinch experiment is somewhat lower than that with an ordinary thete-pinch. This is consistent with a numerical calculation assuming Sagdeev resistivity.  相似文献   
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Two cyano-bridged tetranuclear complexes composed of Mn(III) salen (salen = N,N'-ethylene bis(salicylideneiminate)) and hexacyanometalate(III) (M = Fe, Cr) in a stoichiometry of 3:1 have been selectively synthesized using {NH2(n-C12H25)2}3[M(III)(CN)6] (M(III) = Fe, Cr) starting materials: [{Mn(salen)(EtOH)}3{M(CN)6}] (M = Fe, 1; Cr, 2). Compounds 1 and 2 are isostructural with a T-shaped structure, in which [M(CN)6]3- assumes a meridional-tridentate building block to bind three [Mn(salen)(EtOH)]+ units. The strong frequency dependence and observation of hysteresis on the field dependence of the magnetization indicate that 1 is a single-molecule magnet.  相似文献   
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