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991.
Zygmunt Eckstein Ewa Lipczyńska-Kochany Ewa Leszczyńska 《Monatshefte für Chemie / Chemical Monthly》1983,114(8-9):1009-1011
A series of new quinolinecarbohydroxamic acids has been prepared by treatment of corresponding methyl quinolinecarboxylates with hydroxylamine. 相似文献
992.
993.
994.
The tensor of the hole drift mobility is determined in monoclinic tetracyanoethylene by the transient photoconductivity technique. The principal tensor components amount to μ1 = 0.21, μ2 = 0.10 and μ3 = 0.15 cm2/V s at room temperature. Above 250 K the mobility is a decreasing function of temperature and follows an exp(E/kT) dependence (E = 0.08 eV) which is inconsistent with both band and hopping models. Below 250 K the mobility is controlled by a hole trapping level of 0.28 eV deep. The photogeneration efficiency is found to be independent of temperature and proportional to the light intensity. 相似文献
995.
Partly deuterated NH4HSeO4 crystals were grown from solutions containing 10, 20, 30, 40, 50 and 60% molar deuterium. The deuteration process leads to an increase in the phase transition temperatures. The extrapolated value of ΔTc(∞) for completely deuterated crystals is 25 K. The I2 ? B2(C32) (if a axis is parallel to [110]) symmetry and the ferroelectric transition related to it is observed only in crystals growing from solution containing less than 50% deuterium. The crystals growing from solution containing more than 50% deuterium have a P212121(D42) symmetry. 相似文献
996.
W. Garczyński 《Physics letters. A》1976,56(6):434-436
Equation for distinguished component of a state-vector describing unstable system is solved by means of iterative procedure. Zeroth order of approximation yields the probability amplitude for surviving a given state up to some time t. 相似文献
997.
998.
The mutual relations between s-channel discontinuities of reggeon diagrams with planar triple-Regge vertices are discussed. It is shown that, in general, contributions coming from different cuttings are not simply related to each other as certain vertices acquire non-trivial phase factors depending on the nature of the cutting. For diagrams with only triple-Regge vertices this phase may be related to the triple-Regge phase. The complete four-reggeon vertices are not known in general. An approximation is considered which amounts to preserving only the absorptive part of triple- or four-reggeon amplitudes in certain parts of the diagrams. This approximation turns out to be equivalent to a simple absorbed multiperipheral model. The problem of exchange degeneracy breaking within the dual unitarisation Scheme is briefly discussed as an example. 相似文献
999.
A new approach to the determination of carbon disulphide and carbonyl sulphide in the presence of each other is based on the reaction with 1,3-diaminopropane (DAP), and titration with o-hydroxymercurybenzoie acid (HMB) before and after the selective decomposition of the COS-derivative at pH 4. Determination of hydrogen sulphide, thiols, carbon disulphide and carbonyl sulphide in the presence of each other in hydrocarbon solvents involves four titrations with HMB, viz. of all compounds after conversion of CS(2) and COS with DAP, of thiols plus H(2)S, of the thiols alone after removal of H(2)S by extraction, and of CS(2) alone after removal of other compounds by shaking with aqueous alkali. For selective trapping of H(2)S, HCN, RSH, CO(2) and CS(2) + COS, the sample gas is passed successively through a potassium antimonyl tartrate filter, a nickel carbonate filter, a tributyltin chloride filter, a bubbler containing 40% potassium hydroxide solution and a bubbler containing a benzene solution of DAP. The analysis is completed by titration with HMB with dithizone or dithiofluorescein as indicator. 相似文献
1000.