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931.
932.
White organic light-emitting diodes based on a combined electromer and monomer emission in doubly-doped polymers 下载免费PDF全文
We report on white organic light-emitting diodes(WOLEDs) based on polyvinylcarbazole(PVK) doped with 1,1-bis((di-4-tolylamino)phenyl)cyclohexane(TAPC) and perylene,and investigate the luminescence mechanism of the devices.The chromaticity of light emission can be tuned by adjusting the concentration of the dopants.White light with the Commission Internationale de L’Eclairage(CIE) coordinates of(0.33,0.34) is achieved by mixing the yellow electromer emission of TAPC and the blue monomer emission of perylene from the device ITO/PVK:TAPC:perylene(100:9:1 in wt.)(100 nm)/tris-(8-hydroxyquinoline aluminum(Alq 3)(10 nm)/Al.The device exhibits a maximal luminance of 3727 cd/m2 and a current efficiency of 2cd/A. 相似文献
933.
C Zhang HB Wu C Yuan Z Guo XW Lou 《Angewandte Chemie (International ed. in English)》2012,51(38):9592-9595
Going into their shell: A novel carbon-sulfur nanocomposite has been synthesized by confining sulfur in double-shelled "soft" carbon hollow spheres with high surface area and porosity. This carbon-sulfur nanocomposite shows outstanding electrochemical performance when evaluated as a cathode material for lithium-sulfur batteries. 相似文献
934.
Der-Chyuan Lou Chao-Lung Chou Hao-Kuan Tso Chung-Cheng Chiu 《Optics Communications》2012,285(10-11):2510-2518
This paper presents an innovative active steganalysis algorithm for reversible data hiding schemes based on histogram shifting. These schemes use histogram shifting to embed secret data in cover-images. However, some histogram patterns originating during the embedding procedure may be recognized readily by a steganalyst. The proposed algorithm analyzes the characteristics of histogram changing during the data embedding procedure, and then models these features into reference templates by using a 1 × 4 sliding window. A support vector machine is trained as the classifier for discriminating between cover-images and stego-images by adopting the template matching techniques. The hidden messages located at the histogram peak of the cover-image were further estimated by measuring the feature of adjacent histogram differences. Experimental results indicate that the proposed active steganalysis algorithm can effectively detect stego-images at low bit rates and estimate the hidden messages locations. 相似文献
935.
Yan?ZhaoEmail author Yan-Lin?Liao Ping?Lou 《International Journal of Theoretical Physics》2012,51(7):2109-2112
We propose a concentration scheme of the W class state via cavity QED technique. In our scheme the influences of cavity decay and atomic spontaneous emission have been considered. Furthermore, the atomic spontaneous emission has been suppressed by using non-radiative transitions in atoms with three-level structure, and the photonic qubit is used as flying qubit and atomic qubit as stationary qubit. Therefore our scheme is comparatively easy to realize within techniques presently available. 相似文献
936.
Varnum SM Warner MG Dockendorff B Anheier NC Lou J Marks JD Smith LA Feldhaus MJ Grate JW Bruckner-Lea CJ 《Analytica chimica acta》2006,570(2):137-143
Two immunoassay platforms were developed for either the sensitive or rapid detection of botulinum neurotoxin A (BoNT/A), using high-affinity recombinant monoclonal antibodies against the receptor binding domain of the heavy chain of BoNT/A. These antibodies also bind the same epitopes of the receptor binding domain present on a nontoxic recombinant heavy chain fragment used for assay development and testing in the current study. An enzyme-linked immunosorbent assay (ELISA) microarray using tyramide amplification for localized labeling was developed for the specific and sensitive detection of BoNT. This assay has the sensitivity to detect BoNT in buffer and blood plasma samples down to 14 fM (1.4 pg mL−1). Three capture antibodies and one antibody combination were compared in the development of this assay. Using a selected pair from the same set of recombinant monoclonal antibodies, a renewable surface microcolumn sensor was developed for the rapid detection of BoNT/A in an automated fluidic system. The ELISA microarray assay, because of its sensitivity, offers a screening test with detection limits comparable to the mouse bioassay, with results available in hours instead of days. The renewable surface assay is less sensitive but much faster, providing results in less than 10 min. 相似文献
937.
938.
939.
An original design of ring-core photonic crystal fiber (RPCF) is proposed. By splicing a section of the homemade RPCF between two segments of single mode fibers (SMFs), a simple modal interferometer is presented and experimentally demonstrated. Owing to the effects of the collapsed region, the ring modes in RPCF can be effectively activated. To our knowledge, it is the first time to demonstrate the modal interferometer based on the interference between the ring modes, which is different from the previously reported interferometers based on the interference between core modes or cladding modes. The temperature and strain characteristics of the interferometers with different lengths of RPCF are investigated. 相似文献
940.
Positron-impact ionisation of atomic hydrogen in the presence of a bichromatic laser field 下载免费PDF全文
The positron impact-ionisation of atomic hydrogen in the presence of a linearly polarised bichromatic field is investigated in the first Born approximation.The field is composed of a fundamental frequency and its second harmonic.The state of positron in the field is described by the Volkov wavefunction,and the continuum state of the ejected electron is described by the Coulomb-Volkov wavefunction.The dressed ground state of target is a first order time-dependent perturbative wavefunction.The triple differential cross sections and their dependencies on laser field parameters are discussed and compared with the results modified by a monochromatic field.Numerical results show that the coherent phase control is significant and the laser-assisted ionisation cross sections caused by positron and electron are different. 相似文献