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511.
Deok Kyu Kim Kyeong Min Kim Choon Bae Park 《Applied Physics A: Materials Science & Processing》2010,98(4):913-917
A p-type ZnO thin film was prepared using arsenic diffusion via the ampoule-tube method. This was followed by fabrication
of a ZnO p–n homojunction using n-type ZnO and characterization of the device properties. The ZnO thin film exhibited p-type
characteristics, with a resistivity of 2.19×10−3 Ω cm, a carrier concentration of 1.73×1020/cm3, and a mobility of 26.7 cm2/V s. Secondary ion mass spectrometer analysis confirmed that in- and out-diffusion occurred simultaneously from the external
As source and the GaAs substrate. The device exhibited the rectification characteristics of a typical p–n junction; the forward
voltage at 20 mA was approximately 5.5 V. The reverse-bias leakage current was very low—0.1 mA for −10 V; the breakdown voltage
was −11 V. The ampoule-tube method for fabricating p-type ZnO thin films may be useful in producing ultraviolet ZnO LEDs and
other ZnO-based devices. 相似文献
512.
Some years ago Katriel and Solomon [1] described applications to the characterization of the photon statistics of nonideal lasers, nonclassical light, and deformed photon states using f-deformed coherent states. In this letter, we study the effect of a beam splitter on these nonlinear coherent states. We find that these states are useful for generating quantum entanglement as the deformation parameter gets farther form the unity and for strong input field regimes. The results are confirmed through the Werhl entropy. 相似文献
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514.
A condition for the complete destructive interference of partially coherent fields emerging from pinholes in an opaque screen is derived, with the assumption of symmetry in both their geometric positions and coherence properties. We use this condition to theoretically investigate the simultaneous production of phase singularities of the optical field and of the spectral degree of coherence. We find that in cases where the number of point sources is even, a new type of mixed field/correlation singularity is observed. 相似文献
515.
Pee Choon Toh 《Discrete Mathematics》2012,312(6):1244-1250
Using elementary methods, we establish several new Ramanujan type identities and congruences for certain pairs of partition functions. 相似文献
516.
Differences in electrophoretic behavior between linear and branched PEG‐conjugated proteins 下载免费PDF全文
Eun Ji Park Myung Sun Kim Hye Suk Lee Kang Choon Lee Dong Hee Na 《Electrophoresis》2015,36(6):918-923
The objective of this study was to characterize the differences in electrophoretic behavior between linear and branched PEG‐conjugated proteins. Human growth hormone and alpha‐lactalbumin modified by linear or branched PEGs with molecular weight of 10 kDa were analyzed by SEC, MALDI‐TOF MS, SDS‐PAGE, and microchip CGE (MCGE). Chromatographic and mass spectrometric differences between the linear and branched PEG‐proteins on SEC and MALDI‐TOF MS were small, but their electrophoretic behaviors on SDS‐PAGE and MCGE were significantly different. In particular, MCGE showed significant differences in the peak width and the migration times of linear and branched PEG‐proteins, in which the branched PEG‐proteins exhibited a narrower peak and longer migration time than the linear PEG‐proteins. This phenomenon may explain the longer circulation half‐life for the branched PEG‐proteins observed in previously reported in vivo studies. Consequently, this study indicates that MCGE may be a valuable tool for differentiating linear and branched PEG‐proteins. 相似文献
517.
Koki Kise Shota Ooi Hayate Saito Hideki Yorimitsu Atsuhiro Osuka Takayuki Tanaka 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2022,134(1):e202112589
Peripherally π-extended corannulenes bearing quintuple azahelicene units, 10 and 11 , were prepared and their dynamic behaviors were studied experimentally and theoretically. The fused corannulenes were synthesized from sym-pentabromocorannulene in three steps. X-Ray diffraction analysis for 10 displayed a conformer possessing a P(M) bowl chirality and a PPMPM (PMPMM) helical chirality, which was found to be the most stable conformer(s). Variable-temperature NMR measurements of 10 and 11 revealed that their structural isomers can be interconvertible in solution, depending on the steric congestion around the helical scaffolds. Automated search for conformers in the equilibrium and transition states by Artificial Force Induced Reaction (AFIR) method revealed their interconversion networks, including bowl-inversion and helical-inversion. This analysis indicated that the co-existing corannulene and azahelicene moieties influence the conformational dynamics, which leads to mitigation of the activation energy barriers for isomerization. 相似文献
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520.
Akinobu Kojima Keiji Matsumoto ShunIchiro Ooi Hiroshi Kimoto 《Journal of fluorine chemistry》1980,16(5):417-429
The crystal structure of the title molecule has been determined by single crystal X-ray diffraction method. The molecule crystallizes in the orthorhombic space group Pbca with unit-cell dimensions a = 21.872(8), b = 11.815(6), c = 10.785(6) Å, and Z = 8. The structure has been solved by MULTAN and refined by least-squares calculations to R = 7.62% for 2088 reflections measured by a diffractometer. The molecule has the exo configuration. The central cyclobutane ring is nearly planar. The two five-membered rings are of the envelope conformation. The dihedral angle between the cyclobutane ring and the terminal five-membered ring is 75.5° and that between the cyclobutane ring and the other five-membered ring is 62.2°. 相似文献