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1.
T. Mihara K. Miyamoto M. Kida T. Sasaki N. Aoki Y. Ochiai 《Superlattices and Microstructures》2003,34(3-6):383
A multiwall carbon nanotube crossroads has been fabricated by a manipulation technique using a glass microcapillary, and the low temperature transport properties investigated. The two-terminal conductance of an individual tube shows Tomonaga–Luttinger liquid behavior G∝Tα at high temperature and dI/dV ∝V α at low temperature. However, no evidence of such a power-law behavior is obtained in the four-terminal conductance at the junction, where the conductance shows an almost metallic behavior ‘corrected’ by weak localization. Weak localization would essentially appear in electron states at the junctions of MWNTs. 相似文献
2.
S.S. Joshi 《Applied Surface Science》2006,252(24):8539-8543
In the present work, for the first time, heterojunction has been fabricated using electrochemically deposited isotype p-selenium-p-polyaniline from a single solution bath. The structural characterization of selenium and polyaniline thin film was carried out using XRD technique. Polyaniline exhibited amorphous structure while selenium offered monoclinic (β) phase. The junction was formed by electrodepositing polyaniline over selenium film and heating at 423 K. The current density versus voltage (J-V) plot showed the formation of a junction with ideality factor of 1.16. From J-V characteristics at different temperatures, static resistance (Rs), dynamic resistance (Rd), and rectification ratio of diodes were determined. Heat treatment above 448 K caused junction breakdown. 相似文献
3.
对生长在Si和MgO单晶基片上的不同厚度的单层NbN薄膜、双层薄膜AlN/NbN以及三层薄膜NbN/AlN/NbN应用透射电子显微镜(Transmission Electron Microscope,TEM)技术进行了分析研究,对这几种薄膜样品的微观结构、薄膜厚度以及各个边界的一些直观细节给出了较为清晰的图像。由透射电子显微镜的电子衍射图案计算了薄膜和单晶衬底的晶格常数,并与我们以前采用X射线衍射技术分析的结果进行了比较,结果有很好的吻合。 相似文献
4.
Experimental measurements of the streamwise and transverse velocity components have been acquired in three spanwise/wall-normal planes in the wakes of both a streamlined ‘wing’ and a bluff ‘wing’ junction. The ‘extended’ diagnostic plot introduced by Alfredsson et al. (2011) (see figure 3 therein) is used as a benchmark to locally evaluate the departure of turbulent wing-body junction flow wakes from ‘equilibrium’ boundary layers. Both obstacles produce a secondary flow of Prandtl’s first kind, which disrupts the equilibrium implied by the universality of the extended diagnostic plot. The plane wake of the obstacle itself (away from the junction) also disrupts this equilibrium. It is found that with downstream development the boundary layer eventually recovers to the base zero-pressure-gradient ‘equilibrium’, and that this recovery process emanates from the near-wall region. The transverse velocity components are also examined in “extended diagnostic” form, revealing that the wall-normal fluctuations recover to the zero-pressure-gradient case near the wall more rapidly than the wall-parallel components. 相似文献
5.
设{xn,n≥1}是同分布的两两NQD列,记Sn=∑i=1Xi^n.本文讨论了max |Si|/i(n≥1)的分布函数的上下界.作为应用,获得了随机变量supn≥|Sn|/n型的1阶矩及p(〉1)阶矩分别存在有限的充分必要条件,这是一个与独立同分布场合相一致的结果. 相似文献
6.
Shang-Chao Hung Yan-Kuin Su Shoou-Jinn Chang Liang-Wen Ji Dashen Shen C.H. Huang 《Physica E: Low-dimensional Systems and Nanostructures》2005,30(1-2):13-16
The p–n junction photodiodes with InGaN/GaN MQD have been prepared by metal-organic chemical vapor deposition (MOCVD) growth; we achieved nanoscale InGaN self-assembled QDs in the well layers of the active region. The RT PL spectrum peak position for the fabricated InGaN/GaN MQD p–n Junction PDs is located at 464.6 nm and FWHM is 24.2 nm. After finishing device process, it was fond that the turn on voltage in forward bias and the break down voltage in reverse bias are about 3 and −13.5 V, respectively. Furthermore, with 1, 2, and 3 V applied bias, the maximum responsivity of the fabricated MQD p–n junction PD was observed at 350 nm, and the minimum of spectral response was measured at 465 nm. It was also found that the responsivity was nearly a constant from 390 to 440 nm. It seems to suggest that the spectral response in the range of 390–440 nm is due to the effect of the InGaN dots-in a-well active layers. 相似文献
7.
Ping-Feng Xu Jianhua Guo Man-Lai Tang 《Journal of computational and graphical statistics》2013,22(1):205-229
In this article, we propose localized implementations of the iterative proportional scaling (IPS) procedure by the strategy of partitioning cliques for computing maximum likelihood estimations in large Gaussian graphical models. We first divide the set of cliques into several nonoverlapping and nonempty blocks, and then adjust clique marginals in each block locally. Thus, high-order matrix operations can be avoided and the IPS procedure is accelerated. We modify the Swendsen–Wang Algorithm and apply the simulated annealing algorithm to find an approximation to the optimal partition which leads to the least complexity. This strategy of partitioning cliques can also speed up the existing IIPS and IHT procedures. Numerical experiments are presented to demonstrate the competitive performance of our new implementations and strategies. 相似文献
8.
《Journal of computational and graphical statistics》2013,22(3):746-765
Many studies in the social and behavioral sciences involve multivariate discrete measurements, which are often characterized by the presence of an underlying individual trait, the existence of clusters such as domains of measurements, and the availability of multiple waves of cohort data. Motivated by an application in child development, we propose a class of extended multivariate discrete hidden Markov models for analyzing domain-based measurements of cognition and behavior. A random effects model is used to capture the long-term trait. Additionally, we develop a model selection criterion based on the Bayes factor for the extended hidden Markov model. The National Longitudinal Survey of Youth (NLSY) is used to illustrate the methods. Supplementary technical details and computer codes are available online. 相似文献
9.
Dr. Jia-Nan Chang Qi Li Jing-Wen Shi Dr. Mi Zhang Lei Zhang Shan Li Prof. Yifa Chen Prof. Shun-Li Li Prof. Ya-Qian Lan 《Angewandte Chemie (International ed. in English)》2023,62(9):e202218868
The full reaction photosynthesis of H2O2 that can combine water-oxidation and oxygen-reduction without sacrificial agents is highly demanded to maximize the light-utilization and overcome the complex reaction-process of anthraquinone-oxidation. Here, a kind of oxidation-reduction molecular junction covalent-organic-framework (TTF-BT-COF) has been synthesized through the covalent-coupling of tetrathiafulvalene (photo-oxidation site) and benzothiazole (photo-reduction site), which presents visible-light-adsorption region, effective electron-hole separation-efficiency and photo-redox sites that enables full reaction generation of H2O2. Specifically, a record-high yield (TTF-BT-COF, ≈276 000 μM h−1 g−1) for H2O2 photosynthesis without sacrificial agents has been achieved among porous crystalline photocatalysts. This is the first work that can design oxidation-reduction molecular junction COFs for full reaction photosynthesis of H2O2, which might extend the scope of COFs in H2O2 production. 相似文献
10.
Measurements of the normalised flanking sound level difference of different gypsum board flanking walls are reported. Results of a “standard” wall construction confirmed some results of the current draft standard of DIN 4109. Different constructions with various junction details and different wall constructions are described and measurement results are presented. By additional measurements on the walls, a prediction model for the weighted flanking level difference is suggested, based on the methodology of EN 12354. For the flanking transmission prediction of path Ff, three transmission paths are proposed. The model gives good agreement between calculated and measured weighted flanking level difference except for the case where the transmission along the inner lining of the flanking wall is dominant. In this case the prediction underestimates measurements by up to 7 dB. 相似文献