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1.
Du Yongbo Yu Pengfei Wang Junxiong Zhang Jinping Wang Chang’an Che Defu 《Journal of Thermal Analysis and Calorimetry》2021,143(1):327-334
Journal of Thermal Analysis and Calorimetry - Coal O2/CO2 combustion is a promising carbon capture and storage technology for coal-fired power plant. Char consumption rate prediction is essential... 相似文献
2.
3.
Dr. Yogesh Kumar Maurya Dr. Pingchun Wei Takahide Shimada Dr. Kazuhisa Yamasumi Dr. Shigeki Mori Prof. Dr. Ko Furukawa Dr. Hajime Kusaba Prof. Dr. Tatsumi Ishihara Prof. Dr. Yongshu Xie Dr. Masatoshi Ishida Prof. Dr. Hiroyuki Furuta 《化学:亚洲杂志》2021,16(7):743-747
A facile synthetic strategy towards conformationally stable chiral chromophores based on dimeric porphyrinoids has been established. A peculiar class of face-to-face intramolecularly interlocked corrole dimers were formed by the oxidative C−C coupling linked at the inner carbon sites upon simple treatment of copper(II) ions. Their intrinsic electronic structures were modulated by the peripheral corrole ring annulations, which lead to distinct optical properties and redox profiles. The stereogenic carbon centers implemented in the confused corrole skeleton provided a rationale for designing novel chiral materials. 相似文献
4.
In this study, stoichiometric protonation constants of L-tyrosine, L-cysteine, L-tryptophane, L-lysine, and L-histidine, and
their methyl and ethyl esters in water and ethanol–water mixtures of 30, 50, and 70% ethanol (v/v), were determined potentiometrically
using a combined pH electrode system calibrated as the concentration of hydrogen ion. Titrations were performed at 25∘C and the ionic strength of the medium was maintained at 0.10 mol⋅L−1 using sodium chloride. Protonation constants were calculated by using the BEST computer program. The effect of solvent composition
on the protonation constants is discussed. The log10 K2 values of esters generally decreased with increasing ethanol content. However, the log10 K1 values of the esters of L-tyrosine, L-cysteine, and L-tryptophane were found to increase with increasing ethanol content
in contrast those of L-lysine and L-histidine esters. 相似文献
5.
Dušan Hemzal 《Czechoslovak Journal of Physics》2006,56(12):1467-1479
In this article, general idea of focusing is studied within the framework of optics extension into general relativity (covariant optics). In a configuration of static spacetime, the general, mathematically rigorous treatment of rays, wavefronts and caustics
of spherical symmetry is presented, particularly with regard to problems of obtaining them within general relativity. An original
result is the aberration formulation to covariant optics, whose application is given in this paper; a particular solution
of Einstein equations is finally chosen to provide concrete, exact results of cluster focal length and its aberration structure.
In this way, a gravitational lensing situation is shown to be a true lens. 相似文献
6.
Suppose there exists a global solution u to the incompressible Navier–Stokes equations, such that . We prove that its norm goes to 0 at infinity. We next use this fact to control the norm of u, and finally we prove that such a solution is stable. To cite this article: I. Gallagher et al., C. R. Acad. Sci. Paris, Ser. I 334 (2002) 289–292. 相似文献
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8.
We investigate some topological properties of a normal functorH introduced earlier by Radul which is some functorial compactification of the Hartman-Mycielski construction HM. We prove
that the pair (H X, HMY) is homeomorphic to the pair (Q, σ) for each nondegenerated metrizable compactumX and each denseσ-compact subsetY. 相似文献
9.
Jem‐Kun Chen I‐Kuan Lin Fu‐Hsiang Ko Chih‐Feng Huang Kuo‐Shen Chen Chia‐Hao Chan Feng‐Chih Chang 《Journal of Polymer Science.Polymer Physics》2004,42(22):4063-4074
Polybenzoxazine (PBZZ) thin films can be fabricated by the plasma‐polymerization technique with, as the energy source, plasmas of argon, oxygen, or hydrogen atoms and ions. When benzoxazine (BZZ) films are polymerized through the use of high‐energy argon atoms, electronegative oxygen atoms, or excited hydrogen atoms, the PBZZ films that form possess different properties and morphologies in their surfaces. High‐energy argon atoms provide a thermodynamic factor to initiate the ring‐opening polymerization of BZZ and result in the polymer surface having a grid‐like structure. The ring‐opening polymerization of the BZZ film that is initiated by cationic species such as oxygen atoms in plasma, is propagated around nodule structures to form the PBZZ. The excited hydrogen atom plasma initiates both polymerization and decomposition reactions simultaneously in the BZZ film and results in the formation of a porous structure on the PBZZ surface. We evaluated the surface energies of the PBZZ films polymerized by the action of these three plasmas by measuring the contact angles of diiodomethane and water droplets. The surface roughness of the films range from 0.5 to 26 nm, depending on the type of carrier gas and the plasma‐polymerization time. By estimating changes in thickness, we found that the PBZZ film synthesized by the oxygen plasma‐polymerization process undergoes the slowest rate of etching in CF4 plasma. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 4063–4074, 2004 相似文献
10.
Stefan Cobzaş 《Acta Appl Math》2004,80(3):363-363