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排序方式: 共有1230条查询结果,搜索用时 31 毫秒
1.
Das Pritam Kumar Mallik Arnab Kumar Molla Altaf Hossain Santra Apurba Kumar Ganguly Ranjan Saha Abhijit Kumar Sugam Aswal V. K. 《Journal of Thermal Analysis and Calorimetry》2022,147(10):5617-5635
Journal of Thermal Analysis and Calorimetry - Nanofluids have gained recent attention because of their potential applications in diverse engineering fields like enhancing thermal transport,... 相似文献
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3.
Atsuhiro Fujimori Mikako Ishitsuka Hiroo Nakahara Eisuke Ito Masahiko Hara Kaname Kanai Hisao Ishii Yukio Ouchi Kazuhiko Seki 《Journal of Polymer Science.Polymer Physics》2004,42(12):2329-2336
Photopolymerization of cadmium 10,12-pentacosadiynoate (CdDA) in Langmuir–Blodgett (LB) films, with the molecular packing well arranged by moderate preannealing, was investigated with near-edge X-ray absorption fine structure (NEXAFS) spectroscopy. Greenish films of polydiacetylene with an absorption wavelength of 705 nm were obtained through the photopolymerization of preannealed monomer LB films, and this resulted in an extended π-conjugate system based on the well-ordered monomer in a two-dimensional arrangement. The electronic structures of the polydiacetylenes were found to be correlated to the variation of the molecular arrangements in the films from the changes in the NEXAFS spectra through photopolymerization in the LB films. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 2329–2336, 2004 相似文献
4.
The sub-millisecond protonation dynamics of the chromophore in S65T mutant form of the green fluorescent protein (GFP) was
tracked after a rapid pH jump following laser-induced proton release from the caged photolabile compoundo-nitrobenzaldehyde. Following a jump in pH from 8 to 5 (which is achieved within 2 μs), the fluorescence of S65T GFP decreased
as a single exponential with a time constant of ∼90 μs. This decay is interpreted as the conversion of the deprotonated fluorescent
GFP chromophore to a protonated non-fluorescent species. The protonation kinetics showed dependence on the bulk viscosity
of the solvent, and therefore implicates bulk solvent-controlled protein dynamics in the protonation process. The protonation
is proposed to be a sequential process involving two steps: (a) proton transfer from solvent to the chromophore, and (b) internal
structural rearrangements to stabilize a protonated chromophore. The possible implications of these observations to protein
dynamics in general is discussed 相似文献
5.
M. Wada Y. Ishida T. Nakamura Y. Kanai T. M. Kojima A. Takamine Y. Yamazaki K. Okada A. Yoshida T. Kubo I. Katayama S. Ohtani V. Varentsov H. Wollnik V. Lioubimov H. A. Schuessler 《Hyperfine Interactions》2006,173(1-3):153-163
A next-generation slow radioactive nuclear ion beam facility (SLOWRI) which provides slow, high-purity and small emittance ion beams of all elements is being build as one of the principal facilities at the RIKEN RI-beam factory (RIBF). High energy radioactive ion beams from the projectile fragment separator BigRIPS are thermalized in a large gas catcher cell. The thermalized ions in the gas cell are guided and extracted to a vacuum environment by a combination of dc electric fields and inhomogeneous rf fields (rf carpet ion guide). From there the slow ion beam is delivered via a mass separator and a switchyard to various devices: such as an ion trap, a collinear fast beam apparatus, and a multi-reflection time of flight mass spectrometer. In the R&D works at the present RIKEN facility, an overall efficiency of 5% for a 100A MeV 8Li ion beam from the present projectile fragment separator RIPS was achieved and the dependence of the efficiency on the ion beam intensity was investigated. Recently our first spectroscopy experiment at the prototype SLOWI was performed on Be isotopes. Energetic ions of 10Be and 7Be from the RIPS were trapped and laser cooled in a linear rf trap and the specific mass shifts of these isotopes were measured for the first time. 相似文献
6.
The 57Fe Mössbauer technique has been used to investigate the effect of zinc oxide substitution in (25???x)MnO–xZnO–15Fe2O3–60B2O3 glass system (x?=?0, 5, 10, 15 and 20 mol% of ZnO ). Mössbauer absorption spectra for all the samples recorded at room temperature suggest the existence of the two paramagnetic quadrupole doublets. The observed variations in hyperfine parameters have been explained on the basis of cations distribution and exchange interaction at the lattice sites and it is concluded that B–B interaction increases while the metal–metal interaction decreases due to replacement of manganese oxide by zinc oxide. These results suggest that the present glass system exhibits a paramagnetic behaviour that changes towards the weak paramagnetic when manganese oxide was replaced with zinc oxide. 相似文献
7.
The collision-generated hybridization which has been found responsible for the on-site mixing of the atomic-likef-state and the band-liked states in mixed valence solids has been studied for the cerium solid. A practical expression which depends on the lattice
constant and temperature has been obtained for the collision-generated hybridization. Numerical calculations show that the
valence varies continuously with lattice constant and that temperature makes the transition smoother. The collision-generated
hybridization is found to be of significant strength in the intermediate valence regime; but over a wide range of the valence
near 3.5 it varies rather slowly without preferring a particular valence. Factors which can assist the collision-generated
hybridization in stabilizing the mixed valence phase at a particular lattice constant are discussed. 相似文献
8.
Y. Kanai 《Journal of Radioanalytical and Nuclear Chemistry》2003,255(2):319-323
Geological and geochemical events were elucidated in by using U series nuclides in combination with chemical leaching technique. Two examples were examined: (1) in the apatite-bearing sediment column samples U(VI) is moving, while U(IV) in the samples is almost retained, and (2) the redistribution of U occurred along the column under the monsoon climate. On the other hand, U in the conglomerate sample is divided into 5 categories by the leaching technique, which are related with exchangeable, carbonate, iron oxide, organic/sulfide and silicate components, respectively. Uranium is shown to be abundant in the carbonate and iron rich fractions of conglomerate sediment. Appropriate models are proposed in each case study. 相似文献
9.
Some bounds on the entries and on the norm of the inverse of triangular matrices with nonnegative and monotone entries are found. All the results are obtained by exploiting the properties of the fundamental matrix of the recurrence relation which generates the sequence of the entries of the inverse matrix. One of the results generalizes a theorem contained in a recent article of one of the authors about Toeplitz matrices. 相似文献
10.
Adamovich MI Aggarwal MM Alexandrov YA Ameeva ZV Andreeva NP Anzon ZV Arora R Badyal SK Bhalla KB Bhasin A Bhatia VS Bubnov VI Burnett TH Cai X Chasnikov IY Chernova LP Chernyavski MM Dressel B Eligbaeva GZ Eremenko LE Friedlander EM Gadzhieva SI Gaitinov AS Ganssauge ER Garpman S Gerassimov SG Gill A Grote JG Gulamov KG Gulyamov UG Gupta VK Hackel S Heckman HH Haung H Judek B Kachroo S Kadyrov FG Kalyachkina GS Kanygina EK Kaul GL Kaur M Kharlamov SP Koss T Kumar V Lal P Larionova VG 《Physical review letters》1990,65(4):412-415