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11.
Large enhancements have been observed in the sub-barrier fusion cross sections for Ti+Ni systems in our previous studies. Coupled channel calculations incorporating couplings to 2+ and 3 states failed to explain these enhancements completely. A possibilty of transfer channels contributing to the residual enhancements had been suggested. In order to investigate the role of relevant transfer channels, measurements of one- and two-nucleon transfer were carried out for 46,48Ti+61Ni systems. The present paper gives the results of these studies.  相似文献   
12.
The final stage of self-focusing of 500-ps pulses of a neodymium laser in silicate and phosphate glasses and in the nonlinear liquids perfluorooctane, benzene, and toluene is studied theoretically and experimentally. The formation of spatial solitons, which are stable due to the nonlinearity saturation, is demonstrated. It is found that the intensity of the nonlinearity saturation is close to that of the threshold breakdown for glasses and the role of stimulated Raman scattering is significant for liquids.  相似文献   
13.
In this review phenomenological consequences of the Standard Model extension by means of new spin-1 chiral fields with the internal quantum numbers of the electroweak Higgs doublets are summarized. The prospects for resonance production and detection of the chiral vector Z* and W*± bosons at the LHC energies are considered on the basis of quantitative simulations within the CompHEP/CalcHEP package. The Z* boson can be observed as a Breit-Wigner resonance peak in the invariant dilepton mass distributions in the same way as the well-known extra gauge Z?? bosons. However, the Z* bosons have unique signatures in transverse momentum, angular and pseudorapidity distributions of the final leptons, which allow one to distinguish them from other heavy neutral resonances. In 2010, with 40 pb?1 of the LHC proton-proton data at the energy 7 TeV, the ATLAS detector was used to search for narrow resonances in the invariant mass spectrum of e + e ? and ??+??? final states and high-mass charged states decaying to a charged lepton and a neutrino. No statistically significant excess above the Standard Model expectation was observed. The exclusion mass limits of 1.15 and 1.35 TeV/c 2 were obtained for the chiral neutral Z* and charged W* bosons, respectively. These are the first direct limits on the W* and Z* boson production. Based on the above, a novel strategy for the chiral boson search in the LHC dijet data is discussed. For almost all currently considered exotic models the relevant signal is expected in the central dijet rapidity region y 1,2 ? 0 and |y 1 ? y 2| ? 0. On the contrary, the chiral bosons do not contribute to this region but produce an excess of dijet events far away from it. In particular, for these bosons the appropriate kinematical restrictions lead to a dip in the centrality ratio distribution over the dijet invariant mass instead of a bump expected in the most exotic models.  相似文献   
14.
A change in the quasistatic magnetic susceptibility in thin plates of iron borate (FeBO3), which is a weak ferromagnet, has been revealed at adsorption of water molecules. The measurements have been performed at room temperature with the use of the magneto-optical Faraday effect. The change of the susceptibility in saturated water vapors is about 30%. The observed effect is reversible. The time of establishing the susceptibility after the introduction of water vapors is 1.5 min, which is twice as large as the time of establishing the susceptibility after the evacuation. The effect is explained by the appearance of uniaxial surface magnetic anisotropy in the basal plane because of the adsorption of water molecules.  相似文献   
15.
The decomposition of acid and trisubstituted phosphites containing 1- and 2-adamantyl, cyclohexyl, and ethyl groups in various combinations was studied under electron impact. The major directions for the fragmentation of the compounds studied are related to cleavage of the C-O bond, which is accompanied by migration of one or two hydrogen atoms to the phosphorus-containing fragment. Mono-, di-, and triadamantyl phosphites feature the loss of phosphorous acid (in the case of acid phosphites) or alkylphosphorous acid (n the case of trisubstituted phosphites) from the molecular ion, which leads to the generation of a diadamantyl or alkyladamantyl species. In this case, the charge is localized predominantly on the hydrocarbon fragment.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1676–1678, July, 1990.  相似文献   
16.
17.
Conclusions A study of the photoelectron spectra of benzenechromium tricarbonyl derivatives indicates the virtually complete loss of conjugation between the -aromatic system and the substituent of the coordinated ligand.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1425–1427, June, 1985.The authors express their gratitude to N. K. Baranetskaya and V. I. Losilkina for providing samples of the benzenechromium tricarbonyl derivatives studied.  相似文献   
18.
Direct electrochemical reduction of specially synthesized 2-[(diethoxyphosphorylacetoxy] benzaldehyde on a platinum electrode in an aprotic medium is accompanied by ester bond cleavage, and not formation of coumarin via the phosphonate-anion followed by intramolecular Horner cyclization. This could be realized, as a matter of principle, in the presence of an ionol anion (2,6-di-tert-butyl-4-methylphenoxide), electrochemically generatedin situ.Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 1, pp. 144–146, January, 1993.  相似文献   
19.
X-ray structural analyses have been carried out for 3-aceto-5-cyano-6-dimethyl-aminohexa-3, 5-dien-2-one (I) and Z-7-dimethylamino-2-aceto-4-methylhepta-2,4,6-trienecarboxylic acid methyl ester (II). Introduction of an electron-withdrawing CN-group in the middle of the polyene chain in molecule (I) has been shown to reduce the degree of double bond delocalization. CNDO/2 calculations have also been performed for compound (I) and the resulting atomic charge distribution data are discussed.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 396–402, February, 1991.The authors acknowledge the generosity of Zh. A. Krasnaya and T. S. Stytsenko for providing samples and for valuable discussons of the results.  相似文献   
20.
Hexane-2,5-dione or 1,1,1,10,10,10-hexafluorodecane-2,4,7,9-tetrone react with methyl trifluoroacetate in the presence of LiH to give, upon treatment with diluted acid, 6-hydroxy-9-oxo-2,4,10-tris(trifluoromethyl)-3,11,12-trioxatetracyclo[5,2,1,02,6,04,10]dodecane. The structure of this compound was determined by X-ray diffraction study.  相似文献   
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