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991.
Young Kyu Jeong Jung-Hoon Lee Suk-Jin Ahn Hyun M. Jang 《Solid State Communications》2012,152(13):1112-1115
We have found that SmFeO3, a family of rare-earth orthoferrites, exhibits temperature-induced magnetization reversal below the critical low-temperature along the a-axis of Pbnm symmetry. First-principles calculations demonstrate that this negative magnetization is mainly attributed to the competition between two magnetocrystalline anisotropy terms in the inequivalent magnetic sites of Sm3+ and Fe3+. Interestingly, the room temperature magnetization-field curve further shows an ultra-fast magnetization switch in the low-magnetic field, suggesting a potential applicability to high-speed magnetic switching devices. 相似文献
992.
Ki Hyun Kim Kazuo Watanabe Dietrich Menzel Hans-Joachim Freund 《Surface science》2012,606(15-16):1142-1151
Adsorption states, thermal reactions, and photoreactions at photon energies 2.3–4.7 eV of NO dimers and monomers have been compared between 8-nm silver nanoparticles (Ag NPs) formed on an Al2O3/NiAl(110) substrate and flat Ag(111) surfaces, by thermal desorption (TPD) and by photodesorption using mass selected time-of flight measurements. On the Ag NPs, the (NO)2 and NO species are bound more weakly and with broader variation of adsorption states, compared to Ag(111). For (NO)2 excitation of the Mie plasmon of the Ag NPs with p-polarized 3.5-eV photons enhances the photodesorption cross section (PCS) of NO from (NO)2 by a factor 15 compared to Ag(111); even off the plasmon resonance up to 3-fold PCS enhancement is obtained which we ascribe to hot electron confinement. However, since translational energy distributions of photodesorbed NO are roughly the same on Ag NPs and on Ag(111), common mechanisms of photoexcitation and photoreactions apply on both types of surfaces, and neither enhancement modifies the photoinduced dynamics. Stronger particle-induced influences are observed for the photoinduced NO monomer by changes in its properties, chemical environments, and formation/decay kinetics.Our results show that NPs can lead to considerable changes of efficiency and, under favorable cases, also of branching of photoinduced surface reactions. 相似文献
993.
Younghun Jung Xiaotie Wang Sung Hyun Kim Fan Ren Jihyun Kim Stephen J. Pearton 《固体物理学:研究快报》2012,6(11):421-423
Flexible GaN‐based light‐emitting diodes (LEDs) on polyethylene terephthalate (PET) substrates are demonstrated. The process uses commercial LEDs on patterned sapphire substrates, laser lift‐off (LLO), wet etching for additional surface roughening, and mounting of the freestanding LED on a PET substrate. Electrical and optical properties from the free‐standing LLO‐LEDs mounted on the flexible PET substrates were characterized. The process is scalable to large wafer diameters. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
994.
Hyun Jin Kim 《Designs, Codes and Cryptography》2012,63(1):43-57
We classify the extremal self-dual codes of lengths 38 or 40 having an automorphism of order 3 with six independent 3-cycles,
10 independent 3-cycles, or 12 independent 3-cycles. In this way we complete the classification of binary extremal self-dual
codes of length up to 48 having automorphism of odd prime order. 相似文献
995.
Yong Hyun Shin 《Applied Mathematics Letters》2012,25(7):1087-1093
I consider a continuous-time optimal consumption and portfolio selection problem with voluntary retirement. When the agent’s utility of consumption and leisure are of Cobb–Douglas form, I use the dynamic programming method to derive the value function and optimal strategies in closed-form. These coincide with the solutions of Farhi and Panageas (2007) [7], who have solved the problem using a martingale method. 相似文献
996.
Hua S Nwosu CC Strum JS Seipert RR An HJ Zivkovic AM German JB Lebrilla CB 《Analytical and bioanalytical chemistry》2012,403(5):1291-1302
Glycosylation is one of the most common yet diverse post-translational modifications. Information on glycan heterogeneity
and glycosite occupancy is increasingly recognized as crucial to understanding glycoprotein structure and function. Yet, no
approach currently exists with which to holistically consider both the proteomic and glycomic aspects of a system. Here, we
developed a novel method of comprehensive glycosite profiling using nanoflow liquid chromatography/mass spectrometry (nano-LC/MS)
that shows glycan isomer-specific differentiation on specific sites. Glycoproteins were digested by controlled non-specific
proteolysis in order to produce informative glycopeptides. High-resolution, isomer-sensitive chromatographic separation of
the glycopeptides was achieved using microfluidic chip-based capillaries packed with graphitized carbon. Integrated LC/MS/MS
not only confirmed glycopeptide composition but also differentiated glycan and peptide isomers and yielded structural information
on both the glycan and peptide moieties. Our analysis identified at least 13 distinct glycans (including isomers) corresponding
to five compositions at the single N-glycosylation site on bovine ribonuclease B, 59 distinct glycans at five N-glycosylation sites on bovine lactoferrin, 13 distinct glycans at one N-glycosylation site on four subclasses of human immunoglobulin G, and 20 distinct glycans at five O-glycosylation sites on bovine κ-casein. Porous graphitized carbon provided effective separation of glycopeptide isomers.
The integration of nano-LC with MS and MS/MS of non-specifically cleaved glycopeptides allows quantitative, isomer-sensitive,
and site-specific glycoprotein analysis. 相似文献
997.
Kyung Hyun Choi Maria Mustafa Khalid Rahman Bum Ko Jeong Yang Hui Doh 《Applied Physics A: Materials Science & Processing》2012,106(1):165-170
A prototype memristive device has been presented in this paper, for which the top and bottom electrodes have been fabricated
through a simple and cost-effective technique, i.e. electrohydrodynamic printing. For deposition of the bottom electrode pattern,
a silver ink containing 60 wt% silver by content was subjected to controlled flow through a metal capillary exposed to an
electric field at the ambient temperature to generate an electrohydrodynamic jet, thereby depositing uniform patterns of silver
on glass substrate at a constant substrate speed. The top electrode has been deposited in a similar fashion. In between the
top and bottom electrodes, a uniform layer of ZnO is fabricated using spin-coating technique. The nanoscale ZnO memristor
stack has a channel length of 370 μm and channel width of 82 μm. A memristor thus fabricated was characterized and its current
voltage curves were analyzed. The device showed a typical nonvolatile resistive switching behavior present in memristor devices
thus highlighting the EHD printed patterning as a reliable method for the fabrication of memory devices. 相似文献
998.
999.
1000.
Hoi CT Chang P Aihara H Asner DM Aushev T Bakich AM Belous K Bhardwaj V Bhuyan B Bischofberger M Bondar A Bozek A Bračko M Browder TE Chang MC Chao Y Chen A Chen KF Chen P Cheon BG Chilikin K Cho K Choi Y Danilov M Drásal Z Drutskoy A Eidelman S Fast JE Gaur V Gabyshev N Goh YM Golob B Haba J Hayasaka K Hoshi Y Hou WS Hsiung YB Hyun HJ Inami K Ishikawa A Iwabuchi M Iwasaki Y Iwashita T Kang JH Kawasaki T Kim HJ Kim HO Kim JB Kim JH Kim KT Kim MJ Kinoshita K Ko BR Kobayashi N Kodyš P Korpar S 《Physical review letters》2012,108(3):031801
We report measurements of the branching fractions and CP asymmetries for B(±)→ηh(±) (h=K or π) and the observation of the decay B(0)→ηK(0) from the final data sample of 772×10(6) B ?B pairs collected with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. The measured branching fractions are B(B(±)→ηK(±))=(2.12±0.23±0.11)×10(-6), B(B(±)→ηπ(±))=(4.07±0.26±0.21)×10(-6), and B(B(0)→ηK(0))=(1.27(-0.29)(+0.33)±0.08)×10(-6), where the last decay is observed for the first time with a significance of 5.4 standard deviations (σ). We also find evidence for CP violation in the charged B modes, A(CP)(B(±)→ηK(±))=-0.38±0.11±0.01 and A(CP)(B(±)→ηπ(±))=-0.19±0.06±0.01 with significances of 3.8 σ and 3.0 σ, respectively. For all measurements, the first and second uncertainties are statistical and systematic, respectively. 相似文献