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71.
Santosh RajputChao-wei Leu Kasey WoodDavid StC Black Naresh Kumar 《Tetrahedron letters》2011,52(52):7095-7098
The activated dimethoxypyrrolo[3,2,1-ij]quinolin-6-one ring system was synthesized via two approaches, starting from an indole and quinolin-4-one, respectively. Subsequent demethylation led to both monohydroxy- and dihydroxypyrrolo[3,2,1-ij]quinolin-6-ones. 相似文献
72.
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74.
V. K. Gupta S. K. Badval I. K. Daftari G. L. Kaul L. K. Mangotra N. K. Rao S. K. Sharma Gian Singh Y. Prakash 《Zeitschrift fur Physik C Particles and Fields》1981,10(1):29-36
The shower particle multiplicity (〈n s 〉) in thep-nucleus interactions for different targets, in the incident energy range of ~6–500 GeV has been studied. The variation of multiplicity parameters with target mass (A) or with number of interactions that the incident hadron suffers inside the nucleus (v A ) and with the changed particle multiplicity inp-p interactions (〈n ch〉) has been examined in the light of the various models of multiparticle production. The present analysis favours the hydrodynamical model though some other models can not be conclusively ruled out. 相似文献
75.
Srivastava Santosh Weissler G. L. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1973,1(4):17-22
The lowering of the ionization potentials of hydrogen and carbon atoms immersed in a high temperature and high density thermal plasma generated in a wall stabilized arc have been estimated from the advance or shift of their respective series limits in the vacuum ultraviolet region of the spectrum for different electron densities and temperatures. Results show a close agreement with those theoretical calculations in which the effects of both microfield and polarization terms are added. However, our electron densities are lower by about two orders of magnitude than the critical electron densities required by theory for the inclusion of the microfield term. The question of validity of a critical electrom density will be discussed. 相似文献
76.
K. H. Althoff M. Gies O. Kaul K. Königsmann D. Menze W. Meyer T. Miczaika E. Roderburg W. Schwille 《Zeitschrift fur Physik C Particles and Fields》1979,1(3):257-258
We report the measurement of the differential cross section of the reaction γ +p→π0 +p at a photon energy of 1.4 GeV and pion c.m. angles between 60 and 175 degrees. The angular distribution confirms the simple quark model prediction of a pure magnetic excitation of theF 37 (1950) resonance. 相似文献
77.
78.
A. I. Abramovich O. Yu. Gorbenko A. R. Kaul L. I. Koroleva A. V. Michurin 《Physics of the Solid State》2004,46(9):1711-1716
Magnetic, elastic, magnetoelastic, transport, and magnetotransport properties of the Eu0.55Sr0.45MnO3 ceramics have been studied. A break was detected in the temperature dependence of electrical resistivity ρ(T) near the temperature of the magnetic phase transformation (41 K), with the material remaining an insulator down to the lowest measurement temperature reached (ρ=106 Ω cm at 4.2 K). In the interval 4.2≤T≤50 K, the isotherms of the magnetization, volume magnetostriction, and ρ were observed to undergo jumps at the critical field HC1, which decreases with increasing T. For 50≤T≤120 K, the jumps in the above curves persist, but the pattern of the curves changes and HC1 grows with increasing T. The magnetoresistance Δρ/ρ = (ρ H ?ρH=0)/ρ H is positive for H<HC1 and passes through a maximum at 41 K, where Δρ/ρ = 6%. For H>HC1, the magnetoresistance is negative, passes through a minimum near 41 K, and reaches a colossal value of 3×105 % at H=45 kOe. The volume magnetostriction is negative and attains a giant value of 4.5×10?4atH=45 kOe. The observed properties are assigned to the existence of three phases in Eu0.55Sr0.45MnO3, namely, a ferromagnetic (FM) phase, in which carriers are concentrated because of the gain in s-d exchange energy, and two antiferromagnetic (AFM) phases of the A and CE types. Their fractional volumes at low temperatures were estimated to be as follows: ~3% of the sample volume is occupied by the FM phase; ~67%, by the CE-type AFM phase; and ~30%, by the A-type AFM phase. 相似文献
79.
Phosphoric acid plant wastewater containing fluoride, phosphate and chemical oxygen demand etc., was treated using electrooxidation and electroflocculation methods. A maximum of 82% F- and 22.7% COD were removed using Ti/Pt(5c) under electrooxidative conditions. Electrooxidation with respect to F- removal is found mass-transfer limited, and removals below 5-6 mg/L F- are not achievable. Electroflocculation using Al anode resulted in better removal of F-, COD and PO4(3-). The various results obtained are discussed in this paper. 相似文献
80.
[reaction: see text] The stereoselective intramolecular reductive etherification of delta-trialkylsilyloxy substituted ketones with catalytic bismuth tribromide and triethylsilane provides a convenient method for the construction of cis-2,6-disubstituted tetrahydropyrans. This method was highlighted in the key step of an expeditious total synthesis of the antibiotic, (-)-centrolobine. 相似文献