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981.
The phase φ of any wave is determined by the ratio x/λ consisting of the distance x propagated by the wave and its wavelength λ. Hence, the dependence of φ on λ constitutes an analogue system for the mathematical operation of division, that is to obtain the hyperbolic function f(ξ)≡1/ξ. We take advantage of this observation to decompose integers into primes and implement this approach towards factorization
of numbers in a multi-path Michelson interferometer. This work is part of a larger program geared towards unraveling the connections
between quantum mechanics and number theory. We briefly summarize this aspect. 相似文献
982.
Jisun Kim Alexander Ako Khajetoorians Wenguang Zhu Zhenyu Zhang Chih-Kang Shih 《Surface science》2012,606(3-4):450-455
Using scanning tunneling microscopy (STM), we demonstrate that oxidation on Pb films is greatly enhanced by atomic Cs catalysts. With only a minute concentration of isolated Cs substitutional atoms in the surface layer (0.004 ML coverage), surface oxidation rates are greatly enhanced. First-principles density functional theory (DFT) calculations reveal that a substitutional Cs atom strongly increases O2 binding on the surface. Then, with additional oxygen exposure this substitutional Cs-initiated oxidation process results in growth of PbO layers in an auto-catalytic manner. Furthermore, we investigate the role of temperature in the oxidation of the Pb films with and without Cs, and we explore the overall morphology of the resultant oxide layers. 相似文献
983.
We present a novel parallel Raman microspectroscopy scheme for simultaneously collecting Raman spectra from multiple points. This scheme is realized by projectinga multiple-point laser illumination pattern using a spatial light modulator (SLM) and wide-field Raman imaging collection. We demonstrate the performance of this scheme using uniform samples, trapped polymer microparticles and fixed polymer microparticles with mixed molecular composition within a 50×50 μm(2) field of view. This scheme enables the acquisition of Raman spectra from as many as 40 points simultaneously using a single illumination pattern and detector recording frame without scanning. 相似文献
984.
We present optitrode, a miniaturized flexible probe for integrated, localized light delivery and electrical recording. This device features an annular light guide with transparent polymer and fused silica layers surrounding a twisted-wire tetrode. We have developed a novel fabrication process, V-groove guided capillary assembly, to achieve high-precision, coaxial alignment of the various layers of the device. Optitrode with a length-to-diameter ratio ~500 (5 cm long, 100 μm diameter) has been fabricated, and both the electrical and optical functions have been characterized. The prototype can deliver 11% (110 mW) of the total laser power under abrupt bending angle ~25°. 相似文献
985.
Shao-Ju Shih Ying-Ying Wu Chin-Yi Chen Chin-Yang Yu 《Journal of nanoparticle research》2012,14(5):879
Ceria-based materials are used in industrial applications such as catalyst supports, carbon monoxide reduction catalysts,
and solid oxide fuel cell electrolytes. Various applications require different morphological particles. The ceria particles
with various morphologies from the precursors of cerium(III) acetate hydrate, cerium(IV) nitrate hydrate, and cerium(IV) ammonium
nitrate were prepared by spray pyrolysis (SP) because SP has the potential for simple and continuous process. The precursor
behaviors and the particle morphologies were characterized by thermogravimetric analysis and by transmission electron microscopy.
Four main morphologies of solid spherical, hollow spherical with a single pore, hollow concave, and hollow spherical with
multiple pores were observed. The experimental results suggest that the morphological formation mechanism is highly correlated
with the factors of precursor solubilities, solvent evaporation rates (droplet diameters), and precursor melting temperatures.
In addition, total concentrations of cerium(III) in the ceria particles from various precursors were examined using X-ray
photoelectron spectroscopy. 相似文献
986.
Structure–Performance Correlations of Organic Dyes with an Electron‐Deficient Diphenylquinoxaline Moiety for Dye‐Sensitized Solar Cells
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Dr. Sie‐Rong Li Dr. Chuan‐Pei Lee Po‐Fan Yang Chia‐Wei Liao Mandy M. Lee Dr. Wei‐Lin Su Chun‐Ting Li Prof. Dr. Hao‐Wu Lin Prof. Dr. Kuo‐Chuan Ho Dr. Shih‐Sheng Sun 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(32):10052-10064
The high performances of dye‐sensitized solar cells (DSSCs) based on seven new dyes are disclosed. Herein, the synthesis and electrochemical and photophysical properties of a series of intentionally designed dipolar organic dyes and their application in DSSCs are reported. The molecular structures of the seven organic dyes are composed of a triphenylamine group as an electron donor, a cyanoacrylic acid as an electron acceptor, and an electron‐deficient diphenylquinoxaline moiety integrated in the π‐conjugated spacer between the electron donor and acceptor moieties. The DSSCs based on the dye DJ104 gave the best overall cell performance of 8.06 %; the efficiency of the DSSC based on the standard N719 dye under the same experimental conditions was 8.82 %. The spectral coverage of incident photon‐to‐electron conversion efficiencies extends to the onset at the near‐infrared region due to strong internal charge‐transfer transition as well as the effect of electron‐deficient diphenylquinoxaline to lower the energy gap in these organic dyes. A combined tetraphenyl segment as a hydrophobic barrier in these organic dyes effectively slows down the charge recombination from TiO2 to the electrolyte and boosts the photovoltage, comparable to their RuII counterparts. Detailed spectroscopic studies have revealed the dye structure–cell performance correlations, to allow future design of efficient light‐harvesting organic dyes. 相似文献
987.
Amit Kumar Jacob S. A. Ishibashi Dr. Thomas N. Hooper Tanya C. Mikulas Prof. David A. Dixon Prof. Shih‐Yuan Liu Prof. Andrew S. Weller 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(1):310-322
The coordination chemistry of the 1,2‐BN‐cyclohexanes 2,2‐R2‐1,2‐B,N‐C4H10 (R2=HH, MeH, Me2) with Ir and Rh metal fragments has been studied. This led to the solution (NMR spectroscopy) and solid‐state (X‐ray diffraction) characterization of [Ir(PCy3)2(H)2(η2η2‐H2BNR2C4H8)][BArF4] (NR2=NH2, NMeH) and [Rh(iPr2PCH2CH2CH2PiPr2)(η2η2‐H2BNR2C4H8)][BArF4] (NR2=NH2, NMeH, NMe2). For NR2=NH2 subsequent metal‐promoted, dehydrocoupling shows the eventual formation of the cyclic tricyclic borazine [BNC4H8]3, via amino‐borane and, tentatively characterized using DFT/GIAO chemical shift calculations, cycloborazane intermediates. For NR2=NMeH the final product is the cyclic amino‐borane HBNMeC4H8. The mechanism of dehydrogenation of 2,2‐H,Me‐1,2‐B,N‐C4H10 using the {Rh(iPr2PCH2CH2CH2PiPr2)}+ catalyst has been probed. Catalytic experiments indicate the rapid formation of a dimeric species, [Rh2(iPr2PCH2CH2CH2PiPr2)2H5][BArF4]. Using the initial rate method starting from this dimer, a first‐order relationship to [amine‐borane], but half‐order to [Rh] is established, which is suggested to be due to a rapid dimer–monomer equilibrium operating. 相似文献
988.
989.
Yi-Fen Chiang Cheng-Pei Chung Jing-Hui Lin Wenchang Chiang Hsin-Yuan Chen Mohamed Ali Yin-Hwa Shih Kai-Lee Wang Tsui-Chin Huang Hsin-Yi Chang Li-Chun Lin Tzong-Ming Shieh Shih-Min Hsia 《Molecules (Basel, Switzerland)》2022,27(13)
The antitumor effects of Coix lacryma-jobi L. var. ma-yuen Stapf. (adlay seed) ethanolic extract have been increasingly shown. This study aimed to investigate the beneficial effects of both the fractions and subfractions of adlay seed ethanolic extract on the human breast (MCF-7) and cervical (HeLa) cancer cell lines, as well as exploring their possible mechanisms of action. The ethanolic extracts were obtained from different parts of adlay seed, including AHE (adlay hull extract), ATE (adlay testa extract), ABE (adlay bran extract) and PAE (polished adlay extract). The results of a 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl- tetrazolium bromide (MTT) assay showed that AHE-Ea and ATE-Ea showed significant growth inhibitory effects in a dose-dependent manner. The results also showed that the AHE-Ea-K, AHE-Ea-L, ATE-Ea-E and ATE-Ea-F subfractions inhibited cell proliferation, induced cell cycle arrest in the G0/G1 phase and decreased CDK4/Cyclin D1 protein expression. Finally, the extract activated caspase-3 activity and PARP protein expression, which induced MCF-7 and HeLa cell apoptosis. We then used liquid chromatography–mass spectrometry (LC/MS) to identify the potential active components., Quercetin showed an anticancer capacity. In conclusion, the AHE-Ea-K, AHE-Ea-L, ATE-Ea-E and ATE-Ea-F subfractions showed antitumor effects through the inhibition of MCF-7 and HeLa cell line viability, as well as inducing apoptosis and cell cycle arrest. 相似文献
990.
Senmiao Xu Fredrik Haeffner Bo Li Lev N. Zakharov Shih‐Yuan Liu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(26):6913-6917
We report the first general synthesis of boron‐substituted monobenzofused 1,4‐azaborines using ring‐closing metathesis of an enamine‐containing diene as a key synthetic strategy. As part of our investigations, we discovered that the B‐C3 moiety in a 1,4‐azaborine can serve uniquely as a η2‐L‐type ligand. This functionality is exemplified by two κ2‐N‐η2‐BC Pt complexes of a boron‐pyridyl‐substituted monobenzofused‐1,4‐azaborine. Single‐crystal X‐ray diffraction analysis of the Pt complexes shows a strong structural contribution from the iminium resonance form of the monobenzofused‐1,4‐azaborine ligand. We also demonstrate that a palladium(0) complex supported by a 1,4‐azaborine‐based phosphine ligand can catalyze hydroboration of 1‐buten‐3‐yne with unique selectivity. In view of the importance of arene–metal π‐interactions in catalytic applications, this work should open new opportunities for ligand design involving the 1,4‐azaborine motif as an arene substitute. 相似文献