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51.
Synthesis,Crystal Packing,and Ambipolar Carrier Transport Property of Twisted Dibenzo[g,p]chrysenes 下载免费PDF全文
Dr. Yasuyuki Ueda Dr. Hayato Tsuji Dr. Hideyuki Tanaka Prof. Dr. Eiichi Nakamura 《化学:亚洲杂志》2014,9(6):1623-1628
A versatile method for the synthesis of dibenzo[g,p]chrysene (DBC) derivatives based on regio‐ and stereoselective stannyllithiation to diarylacetylenes is described. This method affords a variety of DBCs possessing both electron‐donating and electron‐withdrawing functional groups. These twisted molecules take brickwork packing structures in single crystals. Thus, ambipolar carrier transport properties with mobility values of up to 10?3 cm2 V?1 s?1 in the amorphous state were achieved. Functional groups on DBC frameworks are considered to increase carrier mobility through the enhancement of intermolecular interactions in the brickwork packing structures. 相似文献
52.
Dr. Hoon Hyun Dr. Hideyuki Wada Dr. Kai Bao Dr. Julien Gravier Dr. Yogesh Yadav Dr. Matt Laramie Dr. Maged Henary Dr. John V. Frangioni Dr. Hak Soo Choi 《Angewandte Chemie (International ed. in English)》2014,53(40):10668-10672
The conventional method for creating targeted contrast agents is to conjugate separate targeting and fluorophore domains. A new strategy is based on the incorporation of targeting moieties into the non‐delocalized structure of pentamethine and heptamethine indocyanines. Using the known affinity of phosphonates for bone minerals in a model system, two families of bifunctional molecules that target bone without requiring a traditional bisphosphonate are synthesized. With peak fluorescence emissions at approximately 700 or 800 nm, these molecules can be used for fluorescence‐assisted resection and exploration (FLARE) dual‐channel imaging. Longitudinal FLARE studies in mice demonstrate that phosphonated near‐infrared fluorophores remain stable in bone for over five weeks, and histological analysis confirms their incorporation into the bone matrix. Taken together, a new strategy for creating ultra‐compact, targeted near‐infrared fluorophores for various bioimaging applications is described. 相似文献
53.
Isothermal Titration Calorimetry Study of a Bistable Supramolecular System: Reversible Complexation of Cryptand[2.2.2] with Potassium Ions 下载免费PDF全文
Maria G. del Rosso Dr. Artur Ciesielski Dr. Silvia Colella Prof. Jack M. Harrowfield Prof. Paolo Samorì 《Chemphyschem》2014,15(13):2743-2748
Isothermal titration calorimetry (ITC) is used to investigate the thermodynamics of the complexation of potassium ions by 1,10‐diaza‐4,7,13,16,21,24‐hexaoxabicyclo[8.8.8]hexacosane (cryptand[2.2.2]) in aqueous solution. By changing the pH of the solution it was possible to trigger the reversible complexation/decomplexation of the cryptand in consecutive in situ experiments and to assess for the first time the use of ITC to monitor the thermodynamics of a bistable system. 相似文献
54.
Ya Zhang Aixue Dong Qiang Wang Xuerong Fan Artur Cavaco-Paulo Ying Zhang 《Applied biochemistry and biotechnology》2014,174(2):820-831
The high-redox-potential catalyst laccase, isolated from Aspergillus, was first used as a biocatalyst in the oxidative polymerization of water-soluble conductive polyaniline, and then conductive cotton was prepared by in situ polymerization under the same conditions. The polymerization of aniline was performed in a water dispersion of sodium dodecylbenzenesulfonate (SDBS) micellar solution with atmospheric oxygen serving as the oxidizing agent. This method is ecologically clean and permits a greater degree of control over the kinetics of the reaction. The conditions for polyaniline synthesis were optimized. Characterizations of the conducting polyaniline and cotton were carried out using Fourier transform infrared spectroscopy, UV–vis spectroscopy, cyclic voltammetry, the fabric induction electrostatic tester, and the far-field EMC shielding effectiveness test fixture. 相似文献
55.
Bruno Medronho Artur J. M. Valente Patrícia Costa Anabela Romano 《Colloid and polymer science》2014,292(4):885-894
The interaction between β-cyclodextrin (β-CD) and the polyphenol rosmarinic acid (RA) is here reported by 1H NMR titration experiments. The formation of an aqueous soluble inclusion complex is confirmed and valuable information regarding mode of penetration of guest into β-CD, stoichiometry, and stability of the complex is obtained. The analysis by the continuous variation method shows the undoubted formation of 1:1 β-CD/RA complex. Additionally, the estimated apparent association constants reveal the importance of the asymmetry of the RA in the complexation; the incorporation of the catechol moiety closer to the carboxylic group is more favorable (K?=?2,028 M?1) than from the other end of the RA molecule (K?=?1,184 M?1). Finally, we have also investigated the antioxidant activity and storage stability of the β-CD/RA complexed system; the presence of β-CD was found to produce a remarkable enhancement on the antioxidant activity. 相似文献
56.
Shogo Ura Kenji Kintaka Hideyuki Awazu Yasuhiro Awatsuji Junji Nishii 《Optical Review》2011,18(1):99-102
An interference exposure system using a phase-shifting mask was proposed for generating periodic sawtooth optical intensity
profile with chirp in period. Multiple space-harmonic waves are launched from the mask by diffraction, and the sawtooth optical
intensity is formed by interference based on Fourier synthesis after propagation through an air gap. The design concept merely
utilizing positive diffraction-order harmonics with tilt illumination of an exposure light and a design algorithm based on
time-reversed configuration for calculating required phase shift amount were proposed and discussed. A phase-shifting mask
for a blazed grating of very high chirp rate was designed to demonstrate its potential and feasibility. The grating period
changes from 2.2 to 3.1 μm gradually within 0.3 mm length. Sawtooth-like optical intensity profile was confirmed by theoretical
simulation as well as preliminary experimental results. 相似文献
57.
Sławomir Prucnal Marcin Turek Andrzej Drozdziel Krzysztof Pyszniak Artur Wójtowicz Sheng-Qiang Zhou Alohe Kanjilal Artem Shalimov Wolfgang Skorupa Jerzy Zuk 《Central European Journal of Physics》2011,9(2):338-343
The InAs quantum structures were formed in silicon by sequential ion implantation and subsequent thermal annealing. Two kinds of crystalline InAs nanostructures were successfully synthesized: nanodots (NDs) and nanopyramids (NPs). The peaks at 215 and 235 cm?1, corresponding to the transverse optical (TO) and longitudinal optical (LO) InAs single-phonon modes, respectively, are clearly visible in the Raman spectra. Moreover, the PL band at around 1.3 µm, due to light emission from InAs NDs with an average diameter 7±2 nm, was observed. The InAs NPs were found only in samples annealed for 20 ms at temperatures ranging from 1000 up to 1200°C. The crystallinity and pyramidal shape of InAs quantum structures were confirmed by HRTEM and XRD techniques. The average size of the NPs is 50 nm base and 50 nm height, and they are oriented parallel to the Si (001) planes. The lattice parameter of the NPs increases from 6.051 to 6.055 Å with the annealing temperature increasing from 1100 to 1200°C, due to lattice relaxation. Energy dispersive spectroscopy (EDS) shows almost stoichiometric composition of the InAs NPs. 相似文献
58.
Artur Bartoszewicz Artur Wachowicz 《Journal of Mathematical Analysis and Applications》2011,375(2):431-435
We answer the questions asked by Faisant et al. (2005) [2]. The first main result states that for every admissible ideal I⊂P(N) the quotient space l∞(I)/c0(I) is complete. The second main result states that consistently there is an admissible ideal I⊂P(N) such that the sets W(I), of all real sequences with finite I-variation, and c?(I), of all restrictively I-convergent sequences, are equal. 相似文献
59.
Forecasting the number of warranty claims is vitally important for manufacturers/warranty providers in preparing fiscal plans. In existing literature, a number of techniques such as log-linear Poisson models, Kalman filter, time series models, and artificial neural network models have been developed. Nevertheless, one might find two weaknesses existing in these approaches: (1) they do not consider the fact that warranty claims reported in the recent months might be more important in forecasting future warranty claims than those reported in the earlier months, and (2) they are developed based on repair rates (i.e., the total number of claims divided by the total number of products in service), which can cause information loss through such an arithmetic-mean operation.To overcome the above two weaknesses, this paper introduces two different approaches to forecasting warranty claims: the first is a weighted support vector regression (SVR) model and the second is a weighted SVR-based time series model. These two approaches can be applied to two scenarios: when only claim rate data are available and when original claim data are available. Two case studies are conducted to validate the two modelling approaches. On the basis of model evaluation over six months ahead forecasting, the results show that the proposed models exhibit superior performance compared to that of multilayer perceptrons, radial basis function networks and ordinary support vector regression models. 相似文献
60.
In this paper we introduce a kind of “noncommutative neighbourhood” of a semiclassical parameter corresponding to the Planck
constant. This construction is defined as a certain filtered and graded algebra with an infinite number of generators indexed
by planar binary leaf-labelled trees. The associated graded algebra (the classical shadow) is interpreted as a “distortion”
of the algebra of classical observables of a physical system. It is proven that there exists a q-analogue of the Weyl quantization, where q is a matrix of formal variables, which induces a nontrivial noncommutative analogue of a Poisson bracket on the classical
shadow. 相似文献