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941.
Secret sharing is a multiparty cryptographic task in which some secret information is split into several pieces which are distributed among the participants such that only an authorized set of participants can reconstruct the original secret. Similar to quantum key distribution, in quantum secret sharing, the secrecy of the shared information relies not on computational assumptions, but on laws of quantum physics. Here, we present an experimental demonstration of four-party quantum secret sharing via the resource of four-photon entanglement.  相似文献   
942.
Summary Recent research has shown that using data fusion rules in fingerprint-based similarity searching can improve results over traditional searches. Group fusion scores, which use multiple reference compounds, have in particular been shown to be quite effective in increasing enrichment rates over single reference structure based searches. In this paper, the effectiveness of using data fusion with multiple reference compounds to increase similarity search recall rates was investigated using 44 biological targets and four different 2D fingerprinting systems, including a new 2D typed triangle fingerprinting system introduced here. Scaffold-hopping abilities using data fusion rules were investigated using eight (8) different classes of scaffolds active against cGMP phosphodiesterase isoform 5 (PDE5). An approach to using the reference group for ranking and visualizing important fingerprints bits, or reverse fingerprinting, was presented, and used to score and visualize important pharmacophore features within sample active molecules. Finally, similarity statistics within the reference groups were investigated and compared to recall rates.  相似文献   
943.
We report on the frictional properties of a single contact between a glassy polymer lens and a flat silica substrate covered either by a disordered or by a self-assembled alkylsilane monolayer. We find that, in contrast to a widely spread belief, the Amontons proportionality between frictional and normal stresses does not hold. Besides, we observe that the velocity dependence of the sliding stress is strongly sensitive to the structure of the silane layer. Analysis of the frictional rheology observed on both disordered and self-assembled monolayers suggests that dissipation is controlled by the plasticity of a glass-like interfacial layer in the former case, and by pinning of polymer chains on the substrate in the latter one.  相似文献   
944.
The replacement of common organic solvents by room-temperature ionic liquids (RTILs) is a topical subject in both academia and industry. In the last decades, the number of applications for RTILs has followed an exponential curve and spilled over the boundaries of chemistry. Still, one of the main drawbacks of these compounds is their difficult access. The present ultrasound-assisted method affords a general and easy access to a large variety of room-temperature ionic liquids.  相似文献   
945.
Near infrared emission caused by ultrasonic excitation is demonstrated for the first time in this work. The instrument is constituted of an acousto-optical tunable filter-based spectrometer, an ultrasonic processor connected to a titanium alloy ultrasonic probe and a cylindrical borosilicate flask containing the sample to be excited. The radiation emitted by the sample is collected by a concave mirror and sent to the spectrometer. The effects of the position of the probe extremity in relation to a lateral entrance of the borosilicate flask and of the ultrasonic power on the emission signal were studied. The best results were obtained by positioning the probe extremity up to 2mm from the reflexive body (lateral entrance) using 30% of the full ultrasonic incident power and acquiring spectra after 5 min of sonication. The NIR emission spectra resulting from the ultrasonic excitation were in agreement with that obtained by thermal excitation. The proposed technique was utilized to study different poly(dimethylsiloxane) samples having different viscosities.  相似文献   
946.
To achieve high-spectral-resolution multiplex coherent anti-Stokes Raman scattering (CARS), one typically uses a narrowband pump pulse and a broadband Stokes pulse. This is to ensure a correspondence between anti-Stokes and vibrational frequencies. We obtain high-resolution CARS spectra of isopropanol, using a broadband chirped pump pulse and a broadband Stokes pulse, by detecting the anti-Stokes pulse with spectral interferometry. With the temporally resolved anti-Stokes signal, we can remove the chirp of the anti-Stokes pulse and restore high spectral resolution while also rejecting nonresonant scattering.  相似文献   
947.
Conti C  Peccianti M  Assanto G 《Optics letters》2006,31(13):2030-2032
Intense light propagating in a nonlinear medium can generate an ensemble of interacting filaments of light, or spatial solitons. Using nematic liquid crystals, we demonstrate that the filaments exhibit collective behavior typical of complex systems, including the formation of clusters and soundlike vibrations, as well as the reduction of the configurational entropy, controlled by the degree of nonlocality of the medium.  相似文献   
948.
采取光电流的飞行时间法测量多个通过P3HT(poly(3-hexylthiophene))氯仿溶液用滴涂法制备的有机薄膜所构成的ITO/P3HT/Al器件中的载流子渡越时间,记录到具有较大数据范围的迁移率分布,将全部数据在P-F图(Poole-Frenkel plot)上分析得到迁移率规律地分为三组,可以判断P3HT中存在有三种或更多的不同载流子输运机制。  相似文献   
949.
In lattice QCD, the maximum entropy method can be used to reconstruct spectral functions from Euclidean correlators obtained in numerical simulations. We show that at finite temperature the most commonly used algorithm, employing Bryan's method, is inherently unstable at small energies and gives a modification that avoids this. We demonstrate this approach using the vector current-current correlator obtained in quenched QCD at finite temperature. Our first results indicate a small electrical conductivity above the deconfinement transition.  相似文献   
950.
Eurysternus caribaeus was analyzed cytologically by conventional chromosomal staining. The species presents a diploid number of 2n=8, chromosomes with two arms and an XY sex determining mechanism. This is the first karyotype described for the genus Eurysternus and the tribe Eurysternini, and is also the smallest diploid number observed in the family Scarabaeidae and superfamily Scarabaeoidea.  相似文献   
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