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821.
822.
Mahamat Saleh Bouetou Bouetou Thomas Timoleon Crepin Kofane 《International Journal of Theoretical Physics》2018,57(9):2640-2647
In this paper, thermodynamics and phase transition are investigated for the regular Bardeen black hole surrounded by quintessence. Considering the metric of the Bardeen spacetime surrounded by quintessence, we derived the Unruh-Verlinde temperature. Using the first law of thermodynamics, we derived the expressions of the Hawking temperature as well as the specific heat for the black hole. Explicitly, their behaviors were plotted. It results that the magnetic monopole charge β as well as the presence of quintessence decrease the temperature and induce a thermodynamics phase transition in the spacetime. Moreover, when increasing the density of quintessence, the transition point moves to lower entropies. 相似文献
823.
Satoshi Nakagawa Isman Kurniawan Koichi Kodama Muhammad Saleh Arwansyah Kazutomo Kawaguchi 《Molecular physics》2018,116(5-6):666-677
ABSTRACTWe present a simple coarse-grained model with the molecular crowding effect in solvent to investigate the structure and dynamics of protein complexes including association and/or dissociation processes and investigate some physical properties such as the structure and the reaction rate from the viewpoint of the hydrophobic intermolecular interactions of protein complex. In the present coarse-grained model, a function depending upon the density of hydrophobic amino acid residues in a binding area of the complex is introduced, and the function involves the molecular crowding effect for the intermolecular interactions of hydrophobic amino acid residues between proteins. We propose a hydrophobic intermolecular potential energy between proteins by using the density-dependent function. The present coarse-grained model is applied to the complex of cytochrome f and plastocyanin by using the Langevin dynamics simulation to investigate some physical properties such as the complex structure, the electron transfer reaction rate constant from plastocyanin to cytochrome f and so on. We find that for proceeding the electron transfer reaction, the distance between metals in their active sites is necessary within about 18 Å. We discuss some typical complex structures formed in the present simulation in relation to the molecular crowding effect on hydrophobic interactions. 相似文献
824.
Polycrystalline cadmium doped gallium selenide thin films were obtained by the thermal co‐evaporation of GaSe crystals and Cd grains onto glass substrates. The structural, compositional and optical properties of these films have been investigated by means of X‐ray diffraction, energy dispersive X‐ray analysis and UV‐visible spectroscopy techniques, respectively. Particularly, the elemental analysis, the crystalline nature, the energy band gap, the refractive index, the dispersion energy and static dielectric constant have been identified. The absorption coefficient spectral analysis in the sharp absorption region revealed a direct forbidden energy band gap of 1.22 eV. The cadmium doping has caused a significant decrease in the values of the energy band gap and in all the dispersive optical parameters, as well. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
825.
S. Ebraheem W. B. Beshir A. Kovacs L. Wojnarovits W. L. McLaughlin 《Radiation Physics and Chemistry》1999,55(5-6):785-787
The electron spin resonance (ESR) readout of radical concentration in irradiated L-alanine is well known as a transfer dosimetry system, however, the high cost of the ESR equipment is a serious handicap for large-scale routine application. In this study the reaction between irradiated L-alanine powder and aqueous solution of triphenyl tetrazolium chloride (TTC) was studied. The radical produced by irradiation of alanine reacts during the dissolution with TTC forming pink-colored formazans with absorption maxima around 401 and 487 nm. This readout method can be used in the 2–200 kGy dose range. 相似文献
826.
827.
828.
Khushbakhat Khan Muhammad Saeed Sameer A. Awad Muhammad Younas Khan Eman M. Khalaf Muhammad Saleh Zaman Vaneeza Aiman Tasmia Irshad Hadia Ahsan 《中国化学会会志》2023,70(1):46-57
The recent study enlightens the synthesis and characterization of zirconia (ZrO2), Fe-doped ZrO2 (Fe@ZrO2), and Ni-doped ZrO2 (Ni@ZrO2) catalysts having new-fangled morphology with tuned band gap as photocatalysts for degradation of textile wastewater dyes methylene blue (MB), malachite green (MG), and their mixtures. SEM imaging of Fe@ZrO2 and Ni@ZrO2 is interestingly varied from ZrO2 as well as doping of transition metals greatly affects the morphology of composites. The optimization study depicts that the pH, time (min) and catalyst amount (g) have a direct relation with degradation efficiency, while the dye concentration (mg/L) has an indirect relation as well. The photocatalytic studies depict that the degradation of MB and MG follows oxidation pathway via hydroxyl radicals (OH•) and holes. Reusability of catalysts corresponds to a little decrease in degradation efficiency in the first two cycles and decreases to about ∼10% (Ni@ZrO2) and ∼12% (Fe@ZrO2) in next three cycles. 相似文献
829.
Balkis Al‐Saleh Mervat Mohammed Abdel‐Khalik Elham Darwich Ossama Abdel‐Motaleb Salah Mohammed Hilmy Elnagdi 《Heteroatom Chemistry》2002,13(2):141-145
The reactivity of benzotriazolylacetone toward a variety of carbon and nitrogen electrophiles is reported. Several novel azolylbenzotriazoles as well as benzotriazolyl‐cinnolines have been synthesized. © 2002 Wiley Periodicals, Inc. Heteroatom Chem 13:141–145, 2002; Published online in Wiley Interscience (www.interscience.wiley.com). DOI 10.1002/hc.10009 相似文献