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951.
O. A. Kolyamshin V. A. Danilov N. I. Kol’tsov 《Russian Journal of Organic Chemistry》2007,43(3):393-396
Reactions of alkyl 4-aminobenzoates with maleic anhydride give the corresponding alkyl 4-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)benzoates, and the latter are converted into 4-(3-dialkylamino-2,5-dioxo-2,3,4,5-tetrahydro-1H-pyrrol-1-yl)benzoates by treatment with secondary amines. 相似文献
952.
Quenching of excited iodine atoms (I(5p5, 2P1/2)) by nitrogen oxides are processes of relevance to discharge-driven oxygen iodine lasers. Rate constants at ambient and elevated temperatures (293-380 K) for quenching of I(2P1/2) atoms by NO2, N2O4, and N2O have been measured using time-resolved I(2P1/2) --> I(2P3/2) 1315 nm emission. The excited atoms were generated by pulsed laser photodissociation of CF3I at 248 nm. The rate constants for I(2P1/2) quenching by NO2 and N2O were found to be independent of temperature over the range examined with average values of (2.9 +/- 0.3) x 10(-15) and (1.4 +/- 0.1) x 10(-15) cm3 s(-1), respectively. The rate constant for quenching of I(2P1/2) by N2O4 was found to be (3.5 +/- 0.5) x 10(-13) cm3 s(-1) at ambient temperature. 相似文献
953.
Evgeniy V. Ivanov Vladimir K. Abrosimov Valeriy I. Smirnov 《The Journal of chemical thermodynamics》2007,39(12):1614-1619
The enthalpies of solution were determined for 1,1,3,3-tetramethylurea in ethanol, 1-propanol, 2-propanol, 1-butanol, and t-butanol (2-methyl-2-propanol). Measurements were made at 298.15 K and molalities m ≅ (0.007 to 0.036) mol · kg−1 with a precise isoperibol ampoule-type calorimeter. Standard enthalpies of solution and transfer from one alkanol to the other (including methanol) were calculated. The obvious relationship between the enthalpic and volumetric effects of solution of tetramethylurea in the n-alkanols (C1-C4) was discovered. The enthalpic effects of transfer caused by branching of the alkanol molecules, 1-propanol → 2-propanol, and 1-butanol → t-butanol, are opposite in sign and dominated by the configurational changes in the solvation environment of tetramethylurea. 相似文献
954.
Chen KF Abe K Abe K Aihara H Asano Y Aulchenko V Aushev T Bahinipati S Bakich AM Bedny I Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Brodzicka J Browder TE Chang MC Chang P Chao Y Chen A Chen WT Cheon BG Chistov R Choi SK Choi Y Chuvikov A Dalseno J Danilov M Dash M Drutskoy A Eidelman S Enari Y Fang F Fratina S Gabyshev N Garmash A Gershon T Gokhroo G Golob B Gorisek A Haba J Hastings NC Hayasaka K Hayashii H Hazumi M Hinz L Hokuue T Hoshi Y Hou S Hou WS Hsiung YB Iijima T Imoto A 《Physical review letters》2005,94(22):221804
We present measurements of decay amplitudes and triple-product correlations in B-->phiK* decays based on 253 fb(-1) of data recorded at the Upsilon(4S) resonance with the Belle detector at the KEKB e(+)e(-) storage ring. The decay amplitudes for the three different helicity states are determined from the angular distributions of final-state particles. The longitudinal polarization amplitudes are found to be 0.45 +/- 0.05 +/- 0.02 for B0-->phiK(*0) and 0.52 +/- 0.08 +/- 0.03 for B+ -->phiK(*+) decays. CP- and T-odd CP-violating triple-product asymmetries are measured to be consistent with zero. 相似文献
955.
Chen KF Bozek A Abe K Abe K Abe T Adachi I Aihara H Akatsu M Asano Y Aso T Bakich AM Ban Y Banas E Bay A Behera PK Bizjak I Bondar A Bracko M Brodzicka J Browder TE Casey BC Chang MC Chang P Chao Y Cheon BG Chistov R Choi SK Choi Y Choi YK Danilov M Dash M Dong LY Drutskoy A Eidelman S Eiges V Enari Y Fukunaga C Gabyshev N Garmash A Gershon T Golob B Guo R Haba J Hagner C Handa F Hayashii H Hazumi M Higuchi T Hinz L Hokuue T Hoshi Y Hou WS Hsiung YB Huang HC Igarashi Y Iijima T Inami K 《Physical review letters》2003,91(20):201801
We present the first measurement of decay amplitudes in B-->phiK* and measurements of branching fractions in B-->phiK(*) decays based on 78.1 fb(-1) of data recorded at the Upsilon(4S) resonance with the Belle detector at the KEKB e+e- storage ring. The decay amplitudes for the different phiK*0 helicity states are measured from the angular distributions of final state particles in the transversity basis. The longitudinal and transverse complex amplitudes are |A0|2=0.43+/-0.09+/-0.04, |A(perpendicular)|2=0.41+/-0.10+/-0.04, arg((A(parallel))=-2.57+/-0.39+/-0.09, and arg((A(perpendicular))=0.48+/-0.32+/-0.06. The direct CP-violating asymmetries are found to be consistent with zero. 相似文献
956.
Yu. A. Boikov I. T. Serenkov V. I. Sakharov V. A. Danilov V. V. Afrosimov 《Physics of the Solid State》2011,53(10):2049-2053
The structure, orientation, and the response of electroresistance to magnetic field H and varying temperature T have been studied for 30-nm-thick La0.67Ba0.33MnO3 (LBMO) films. The deviation of the [001] direction in manganite layers from the normal to the plane of the (LaAlO3)0.29 + (SrAl0.5Ta0.5O3)0.71 substrate strictly corresponds to the vicinal angle of the latter. The minimum yield determined from 227-keV proton scattering
spectra is 0.025, signifying a high order of the cationic sublattice in the films. The biaxial compression of stable nuclei
of the manganite phase affects their stoichiometry, thus contributing to the depletion of LBMO films in the alkaline-earth
element. The maximum electroresistance values have been observed in the films grown at T
max ≈ 320 K, a temperature about 20 K lower than the Curie temperature of the corresponding bulk single crystals, and the maximum
magnetoresistance (MR ≈ −0.42, μ0
H = 2 T) occurs at T ≈ 300 K. At low temperatures (T < T
max/3) and μ0
H < 0.45 T, the electroresistance response of LBMO films to a magnetic field materially depends on the anisotropic magnetoresistance
and the intensity of hole scattering from domain walls; when μ0
H > 0.5 T, the major current-carrier relaxation mechanism is the interaction with magnons. 相似文献
957.
958.
Experimental data on the electrical and optical properties of a thin layer of a magnetodielectric colloid obtained by Kozhevnikov
et al. (Tech. Phys. 51 (7), 946 (2006)), are analyzed. Using a three-layer hierarchical model, the possible structure and properties of near-electrode
layers are determined, the formation mechanisms of dynamic structures are described, and the variation of the electrical properties
of the magnetodielectric colloid layer with time and constant electric field strength are discussed. 相似文献
959.
960.
P. A. Danilov D. A. Zayarny A. A. Ionin S. I. Kudryashov T. T. H. Nguyen A. A. Rudenko I. N. Saraeva A. A. Kuchmizhak O. B. Vitrik Yu. N. Kulchin 《JETP Letters》2016,103(8):549-552
Submicron dimensions, nanoscale crystalline structure, and fabrication mechanisms of microcones on silver films of variable (50–380 nm) thickness deposited onto glass substrates by single strongly focused femtosecond laser pulses of different fluences are experimentally studied using scanning electron microscopy. Fabrication mechanisms for nanoholes and microcones are discussed for films of the different thickness, as well as the extraordinary shapes of their constituent nanocrystallites, strongly elongated along the melt flow direction in thin films. 相似文献