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891.
We determine the bicyclic graphs of fixed order and number of pendant vertices with exactly two (three, respectively) cycles for which the least eigenvalue is minimal. 相似文献
892.
Michael I. Mishchenko Li Liu Igor V. Geogdzhayev Jing Li Barbara E. Carlson Andrew A. Lacis Brian Cairns Larry D. Travis 《Journal of Quantitative Spectroscopy & Radiative Transfer》2012,113(15):1974-1980
The nominal Global Aerosol Climatology Project (GACP) record of aerosol optical thickness (AOT) and Ångström exponent (AE) over the oceans is extended by 6 months to cover the period from August 1981 through December 2005. The most recent 4-year segment reveals no significant short-term tendencies in globally and hemispherically averaged AOTs and AEs. This finding is consistent with contemporaneous MODIS and MISR results and the accumulating evidence of a gradual transition from global brightening to global dimming. We also analyze the retrieval implications of allowing the imaginary part of the aerosols refractive index Im(m) to change over the duration of the GACP record. Our sensitivity study shows that increasing Im(m) from 0.003 during the 4-year pre-Pinatubo period up to 0.007 during the most recent 4-year segment of GACP data eliminates the previously identified long-term decreasing AOT trend. Should this long-term trend in Im(m) be real then it would cause the global absorption AOT over the oceans to more than double and the global single-scattering albedo to decrease from ~0.95 to ~0.88. Such changes could make tropospheric aerosols significant contributors to the recent surface temperature increase. 相似文献
893.
Patrick Homenya Markus Messerschmidt Muhammad Nawaz Tahir Victor Martinez Yajun Cheng Jochen S. Gutmann Michael Klein Stefan Jung Morris Wolff Reza Saadat Driss Nariaki Roman Bo?a G?star Klingelh?fer Wolfgang Tremel Franz Renz 《Hyperfine Interactions》2012,205(1-3):63-67
The nonanuclear coordination compound [MoIV{(CN)FeIII(3-methyl-saldptn)}8]Cl4 exhibits multiple spin transitions (3-methyl-saldptn = N,N′-bis(3′′-methyl-2′′-hydroxy-benzyliden)-1,7-diamino-4-azaheptane). This spin crossover cluster is bound via a self-assembled monolayer onto a two dimensional array gold surface. M?ssbauer spectroscopy indicates that the thermally and optically induced spin crossover of the compound is maintained. Thereby, the foundation for its potential practical application (e.g. in the field of information storage) was laid. 相似文献
894.
Monolithic integration of an AlGaN/GaN metalinsulator field-effect transistor with an ultra-low voltage-drop diode for self-protection 下载免费PDF全文
In this paper,we present a monolithic integration of a self-protected AlGaN/GaN metal-insulator field-effect transistor(MISFET).An integrated field-controlled diode on the drain side of the AlGaN/GaN MISFET features a selfprotected function for a reverse bias.This diode takes advantage of the recessed-barrier enhancement-mode technique to realize an ultra-low voltage drop and a low turn-ON voltage.In the smart monolithic integration,this integrated diode can block a reverse bias(> 70 V/μm) and suppress the leakage current(< 5 × 10-11 A/mm).Compared with conventional monolithic integration,the numerical results show that the MISFET integrated with a field-controlled diode leads to a good performance for smart power integration.And the power loss is lower than 50% in conduction without forward current degeneration. 相似文献
895.
896.
897.
The mechanism of dimethyl oxalate hydrogenation to ethylene glycol over Cu/SiO2 catalyst was investigated by in situ Fourier transform infrared(FTIR)spectroscopy.It was found that dimethyl oxalate and methyl glycolate proceeded via dissociative adsorption on Cu/SiO2 catalyst,and four main intermediates,CH3OC(O)(O)C-M(1655 cm-1),M-C(O)(O)C-M(1618 cm-1),HOCH2(O)C-M(1682 cm-1)and CH3O-M(2924-2926 cm-1),were identified during the reaction.It was concluded that dimethyl oxalate hydrogenation to ethylene glycol mainly proceeded along the route:dimethyl oxalate →CH3OC(O)(O)C-M→ methyl glycolate →HOCH2(O)C-M→ ethylene glycol.Finally a schematic reaction network was proposed. 相似文献
898.
Xiang-Yao Wu Bo-Jun Zhang Xiao-Jing Liu Hong Li Si-Qi Zhang Jing Wang Yi-Heng Wu Jing-Wu Li 《International Journal of Theoretical Physics》2013,52(2):549-558
In this paper, we study two-photon ghost interference with the approach of photon quantum theory, and calculate the coincidence counts of D 1 and D 1 detectors. With specific attention to the two-photon interference experiment carried out by Milena D’Angelo et al. (Phys. Rev. Lett. 87:013602, 2001), and find the theoretical result is accordance with experiment data. 相似文献
899.