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201.
202.
Synthetic organic chemists are continually looking for milder, more specific methods of effecting given transformations, and one such problem which recently arose in our laboratory involved ester cleavage. In particular, we sought a specific, wild, non-hydrolytic method for effecting teh ester - acid transformation under conditions which other acid or base sensitive functional groups would survive. 相似文献
203.
A k-regular bipartite graph is said to be 2-factor hamiltonian if each of its 2-factor is hamiltonian. It is well known that if a k-regular bipartite graph is 2-factor hamiltonian, then k?Q3. In this paper, we give a new proof of this fact. 相似文献
204.
In this study, cultural, economic as well as certain crucial demographic factors are considered as the determinants for projecting the average family size in rural India. We use the Analytic Hierarchy Process to analyze influences of the factors which enter implicitly in a rural couple's decision‐making to determine the number of children they want to have as time goes by. We did not attempt to make distinctions among the regional differences in rural India. The outcome projected in our analysis compares favorably with the results of other demographic studies. 相似文献
205.
Although divalent organophosphinyl radicals have been frequently postulated as intermediates in many organochosphorous reactions, very few of them have been identified by e.s.r. By low temperature trapping of products from the photolysis of gaseous tetraphenyl-diphospine in a flow system, Schmidt and coworkers2 have observed an e.s.r. signal of a single broad and asymmetric line centered at about g = 2.009 and have assigned this to the diphenylphosphinyl radical. We have reinvestigated the photolysis of this compound by flash photolysis and by e.s.r. at low temperatures, the preliminary e.s.r. results will be reported here. 相似文献
206.
The production of track-spots in CR-39 detectors for alpha particles and the subsequent optical counting of the detectors are often influenced by foreign substances deposited on the surface of the detectors. The removal of these substances can be achieved using chemicals for pre-irradiation treatment. Two methods of pre-irradiation treatment were studied in the present experiments. One of them involves the dipping of the detectors in ethanol. In the other method, the detectors were treated in 6N KOH etchant prior to exposure. It was found that prolonged treatment could only produce a reduction in the track density of less than 20%. 相似文献
207.
208.
The purpose of this paper is to construct two superimposed optimization methods for solving the mixed equilibrium problem and variational inclusion. We show that the proposed superimposed methods converge strongly to a solution of some optimization problem. Note that our methods do not involve any projection. 相似文献
209.
Hing Shing Man 《代数通讯》2013,41(12):3271-3294
210.
Symmetrical and cyclic alkyl trithiocarbonates were synthesized by reacting CS2 and 33% aqueous NaOH with alkyl hal-ides under phase transfer catalysis conditions 相似文献