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Experimental results are reported of investigations of the optical properties of the plasma produced when an AI2O3 target is irradiated in vacuum by a high-power neodymiunr-glass laser system. It is shown that a number of 0 VIII and 0 VII ion levels with principal quantum numbers n = 2, 3, 4 are inversely populated. The gain at the wavelength 29 nm (4 3 transition, O VIII) under the experimental conditions is of the order of 0.01 cm-1. For the heliumlike ions O VII, in a transition with the same principal quantum numbers (ls4p1P1 ls3s1S0, 36.9 nm), the gain is of the order of 10-2–10-1 cm-1, depending on the electron density.Translated from Lazernye Sistemy, pp. 5–14 1982.  相似文献   
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Summary Optically pure (+)-beta-eudesmol is a possible starting material for the synthesis of several termite defense compounds. A two step procedure for the isolation of gram quantities of (+)-beta-eudesmol from commercially availableAmyris balsamifera oil (syn. West Indian sandalwood oil), containing 8% beta-eudesmol, was developed. Step one consisted of an efficient vacuum distillation of the total oil. Step two was a medium pressure LC separation with an AgNO3 impregnated silica gel stationary phase. Several other separation procedures failed due to the presence of many closely related sesquiterpene alcohols (75% of the oil).  相似文献   
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The ignition delay times for mixtures of isopropyl nitrate (IPN) with air and argon are measured in a rapid-injection reactor at a pressure of 1 atm and in a shock tube at 2–3 atm. It is shown that the ignition delay time τ of mixtures in which heat is largely released due to oxidation by the oxygen contained in the IPN molecule is determined by the unimolecular decomposition of IPN over the entire temperature range covered (500–730 K). For mixtures in which heat is mainly produced by oxidation reactions involving air oxygen, the ignition delay time at high temperatures is controlled by secondary reactions of oxidation of the hydrocarbon moiety of the IPN molecule, leading to an increase in τ by more than an order of magnitude. Liquid IPN burns in a nitrogen atmosphere only at pressures above 40 atm, at a linear rate of ~4 mm/s. The measured flame temperatures are in close agreement with the respective values calculated using a thermodynamic code.  相似文献   
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The relativistic scattering was one of the scientific fields where Academician V.G. Kadyshevsky has made an important and highly cited contribution [1]. In this paper we discuss the high-energy dependencies of diffractive and non-diffractive inelastic cross-sections in view of the recent LHC data which reveal a presence of the reflective scattering mode.  相似文献   
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Russian Chemical Bulletin - Regularities of interaction of water-soluble pentaamino acid derivatives of fullerenes (WPDFs) with the lipid bilayer of phosphatidylcholine liposomes were studied using...  相似文献   
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