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111.
Abe Y Aberle C Akiri T dos Anjos JC Ardellier F Barbosa AF Baxter A Bergevin M Bernstein A Bezerra TJ Bezrukhov L Blucher E Bongrand M Bowden NS Buck C Busenitz J Cabrera A Caden E Camilleri L Carr R Cerrada M Chang PJ Chimenti P Classen T Collin AP Conover E Conrad JM Cormon S Crespo-Anadón JI Cribier M Crum K Cucoanes A D'Agostino MV Damon E Dawson JV Dazeley S Dierckxsens M Dietrich D Djurcic Z Dracos M Durand V Efremenko Y Elnimr M Endo Y Etenko A Falk E Fallot M Fechner M von Feilitzsch F 《Physical review letters》2012,108(13):131801
The Double Chooz experiment presents an indication of reactor electron antineutrino disappearance consistent with neutrino oscillations. An observed-to-predicted ratio of events of 0.944±0.016(stat)±0.040(syst) was obtained in 101 days of running at the Chooz nuclear power plant in France, with two 4.25 GW(th) reactors. The results were obtained from a single 10 m(3) fiducial volume detector located 1050 m from the two reactor cores. The reactor antineutrino flux prediction used the Bugey4 flux measurement after correction for differences in core composition. The deficit can be interpreted as an indication of a nonzero value of the still unmeasured neutrino mixing parameter sin(2)2θ(13). Analyzing both the rate of the prompt positrons and their energy spectrum, we find sin(2)2θ(13)=0.086±0.041(stat)±0.030(syst), or, at 90% C.L., 0.017相似文献
112.
Fractional Fourier-domain random encoding and pixel scrambling technique for double image encryption
A double image encryption method is proposed using fractional Fourier-domain random encoding and pixel scrambling technique. One of the two original images is encoded into the phase function of a synthesized input signal after being scrambled, and the other original image encoded into its amplitude. The phase function serves as phase mask in the input domain, and the synthesized input signal is then encrypted into stationary white noise by utilizing random phase encoding in fractional Fourier domain. The two original images can be retrieved without cross-talk by using the correct keys with fractional orders, the random phase mask and the pixel scrambling operator. Numerical simulations and security analysis have been done to prove the validity and the security of the proposed encryption method. 相似文献
113.
Stephen L. A. Hennart Pim van Hee Willem J. Wildeboer Gabriel M. H. Meesters 《Particle & Particle Systems Characterization》2012,29(4):285-303
The present research aims to characterize the particle size distribution of sub micron particles suspended in a liquid. The particles milled are an organic poorly water soluble crystalline product. To characterize the size of these particles, different techniques have been tested: imaging techniques (SEM, CryoTEM), static light scattering techniques, dynamic light scattering techniques, centrifugation and flow field flow fractionation. The results indicate that the studied milled particles have a primary particle size close to 180nm and there is strong evidence of larger particles which are very likely aggregates. This is clearly seen from the Cryo TEM results. All the above mentioned techniques should in principle be able to measure samples of dispersion containing particles of ca 180 nm but several are disturbed by the presence of large aggregates. It is difficult to estimate the amount of aggregate present, but most of the time one is interested in what the primary particle size distribution is. It is clear that no single piece of equipment is capable of exactly determining the particle size distribution of our samples, but the static light scattering with low shear on mixing does give a good representation of what is seen with the image analysis by cryo TEM. 相似文献
114.
Seung Yoon Ryu Sung Hyun Kim Chang Su Kim Sungjin Jo Jun Yeob Lee 《Current Applied Physics》2012,12(5):1378-1380
Stacked organic light-emitting diodes (SOLEDs) with 30-nm nanoparticle (NP) interfacial layers were investigated. Zinc oxide (ZnO) was used as an interfacial layer between two green polymer (GP) layers. SOLEDs with NP interfacial layers had higher device efficiency than did a single-unit device due to the high probability of exciton recombination that originated from the Auger electron-assisted energy up-conversion process. Although the current density and luminance of SOLEDs with ZnO NP interfacial layers were smaller than those of the reference device, the efficiency was doubled because of the big band alignment difference and the large band gap between GP and ZnO NP interfacial layers, which induced more radiative-exciton recombination. 相似文献
115.
116.
Krokovny P Abe K Abe K Abe T Adachi I Ahn BS Aihara H Akatsu M Asano Y Aso T Aulchenko V Aushev T Bakich AM Ban Y Banas E Bay A Bedny I Behera PK Bizjak I Bondar A Bozek A Bracko M Brodzicka J Browder TE Casey BC Chang P Chao Y Chen KF Cheon BG Chistov R Choi SK Choi Y Danilov M Dong LY Drutskoy A Eidelman S Eiges V Enari Y Everton CW Fang F Fukunaga C Gabyshev N Garmash A Gershon T Golob B Gordon A Guo R Haba J Hanagaki K Handa F Harada Y Hayashii H Hazumi M Heenan EM Higuchi T Hinz L Hojo T 《Physical review letters》2002,89(23):231804
We report the first observation of a B meson decay that is not accessible by a direct spectator process. The channel B(0)-->D(+)(s)K- is found in a sample of 85 x 10(6) BB; events, collected with the Belle detector at KEKB, with a branching fraction B(B(0)-->D(+)(s)K-)=(4.6(+1.2)(-1.1)+/-1.3) x 10(-5). We also obtain evidence for the B0-->D(+)(s)pi(-) decay with branching fraction B(B0-->D(+)(s)pi(-))=(2.4(+1.0)(-0.8)+/-0.7) x 10(-5). This value may be used to extract a model-dependent value of |V(ub)|. 相似文献
117.
This paper proposed a method of generating two attractors in a novel grid multi-scroll chaotic system.Based on a newly generated three-dimensional system,a two-attractor grid multi-scroll attractor system can be generated by adding two triangular waves and a sign function.Some basic dynamical properties,such as equilibrium points,bifurcations,and phase diagrams,were studied.Furthermore,the system was experimentally confirmed by an electronic circuit.The circuit simulation results and numerical simulation results verified the feasibility of this method. 相似文献
118.
Chi‐Jen Liu Chang‐Hai Wang Cheng‐Liang Wang Y. Hwu Chien‐Yi Lin G. Margaritondo 《Journal of synchrotron radiation》2009,16(3):395-397
Dose measurements based on methylene blue (MB) bleaching, widely used for ultraviolet light, can also be applied to X‐rays including very high flux levels. This method has been tested by using both MB bleaching and Fricke dosimetry for a conventional monochromatic X‐ray source and then for `white‐beam' synchrotron radiation. The results show that MB bleaching dosimetry can easily measure X‐ray doses up to at least 105 Gy s?1, as long as the MB concentration is sufficiently high. This condition can be verified from the deviations from linearity of the bleaching versus exposure time. 相似文献
119.
120.
Temperature-dependent photoluminescence (PL) measurements were carried out ZnSe/ZnS quantum dots (QDs) grown with post-growth interruption under a dimethylzinc (DMZn) flow. The PL spectra showed sigmoidal peak shifts and V-shaped full width at half maximum (FWHM) variations with increasing temperature, which strongly suggest that the QD structure of ZnSe/ZnS is quite similar to that of other material systems grown in the Stranski–Krastanov mode. Apparent differences are revealed as a consequence of DMZn treatment: (i) the PL spectra of ZnSe/ZnS QDs showed peaks at higher energies and persisted up to 300 K, and(ii) the minimum points of the V-shaped FWHM appear at a higher temperature compared to H2-purged ZnSe/ZnS QDs. Experimental results demonstrate the enhancement of localization energy. 相似文献