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991.
We determine the complete set of generalized spin squeezing inequalities, given in terms of the collective angular momentum components, for particles with an arbitrary spin. They can be used for the experimental detection of entanglement in an ensemble in which the particles cannot be individually addressed. We also present a large set of criteria involving collective observables different from the angular momentum coordinates. We show that some of the inequalities can be used to detect k-particle entanglement and bound entanglement. 相似文献
992.
993.
Alessandro Lo Giudice Paolo Olivero Claudio Manfredotti Marco Marinelli Enrico Milani Federico Picollo Giuseppe Prestopino Alessandro Re Valentino Rigato Claudio Verona Gianluca Verona‐Rinati Ettore Vittone 《固体物理学:研究快报》2011,5(2):80-82
In order to evaluate the charge collection efficiency (CCE) profile of single‐crystal diamond devices based on a p‐type/intrinsic/metal configuration, a lateral Ion Beam Induced Charge (IBIC) analysis was performed over their cleaved cross sections using a 2 MeV proton microbeam. CCE profiles in the depth direction were extracted from the cross‐sectional maps at variable bias voltage. IBIC spectra relevant to the depletion region extending beneath the frontal Schottky electrode show a 100% CCE, with a spectral resolution of about 1.5%. The dependence of the width of the high efficiency region from applied bias voltage allows the constant residual doping concentration of the active region to be evaluated. The region where the electric field is absent shows an exponentially decreasing CCE profile, from which it is possible to estimate the diffusion length of the minority carriers by means of a drift–diffusion model. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
994.
Danilo Babusci Giuseppe Dattoli Dario Sacchetti 《Central European Journal of Physics》2011,9(6):1381-1386
The Airy transform is an ideally suited tool to treat problems in classical and quantum optics. Even though the relevant mathematical
aspects have been thoroughly investigated, the possibilities it offers are wide and some features, such as the link with special
functions and polynomials, still contain unexplored aspects. In this note we will show that the so called Airy polynomials
are essentially the third order Hermite polynomials. We will also prove that this identification opens the possibility of
developing new conjectures on the properties of this family of polynomials. 相似文献
995.
Andrew K. Johnson Jozef Kaczor Hongmei Han Maninder Kaur Guoxin Tian Linfeng Rao You Qiang Andrzej J. Paszczynski 《Journal of nanoparticle research》2011,13(10):4881-4895
The creation of multifunctional nanomaterials by combining organic and inorganic components is a growing trend in nanoscience. The unique size-dependent properties of magnetic nanoparticles (MNPs) make them amenable to numerous applications such as carriers of expensive biological catalysts, in magnetically assisted chemical separation of heavy metals and radionuclides from contaminated water sources. The separation of minor actinides from high-level radionuclide waste requires a sorbent stable in acidic pH, with ease of surface functionalization, and a high capacity for binding the molecules of interest. For the described experiments, the MNPs with 50 nm average size were used (size distribution from 20 to 100 nm and an iron content of 80–90 w/w%). The MNPs that have been double coated with an initial silica coating for protection against iron solubilization and oxidation in nitric acid solution (pH 1) and a second silica/polymer composite coating incorporating partially imbedded poly(allylamine) (PA). The final product is magnetic, highly swelling, containing >95% water, with >0.5 mmol amines g?1 available for functionalization. The amine groups of the magnetic resin were functionalized with the chelating molecules diethylenetriaminepentaacetic acid (DTPA) and N,N-dimethyl-3-oxa-glutaramic acid (DMOGA) for separation of minor actinides from used nuclear fuel. 相似文献
996.
V. Ganesh Ch. Snehalatha ReddyMohd. Shakir M.A. WahabG. Bhagavannarayana K. Kishan Rao 《Physica B: Condensed Matter》2011,406(2):259-264
〈1 1 1〉 oriented bis thiourea cadmium acetate (BTCA) crystal of diameter 15 mm and length 45 mm was grown for the first time by the unidirectional Sankaranarayanan-Ramasamy (SR) method. The conventional and SR method grown BTCA crystals were characterized by using high-resolution X-ray diffraction (HRXRD), chemical etching, Vickers microhardness, UV-vis, dielectric studies and differential scanning calorimetry. The HRXRD analysis indicates that the crystalline perfection of SR method grown crystal is good without having any low angle internal structural grain boundaries. The transmittance of SR method grown BTCA is 14% higher than that of conventional grown crystal. The dielectric constant was higher and the dielectric loss was less in SR method grown crystal. The crystals grown by SR method possess less dislocation density and higher microhardness. 相似文献
997.
T. Raghavendra RaoCh. Rama Krishna U.S. Udayachandran ThampyCh. Venkata Reddy Y.P. ReddyP. Sambasiva Rao R.V.S.S.N. Ravikumar 《Physica B: Condensed Matter》2011,406(11):2132-2137
The effect of Li2O content in vanadyl doped 20ZnO+xLi2O+(30−x)Na2O+50B2O3 (5≤x≥25) glasses has been studied with respect to their physical and structural properties. The absence of sharp peaks in XRD spectra of these glass samples confirms the amorphous nature. The physical parameters like density, refractive index, ionic concentration and electronic polarizability vary non-linearly with x mol% depending on the diffusivities of alkali ions. EPR and optical absorption spectra reveal that the resonance signals are characteristics of VO2+ ions in tetragonally compressed octahedral site. Spin-Hamiltonian, crystal field, tetragonal field and bonding parameters are found to be in good agreement with the other reported glass systems. The tetragonal distortion (g⊥-g∥) and Dt reveals that their values vary non-linearly with Li2O content and reaches a minimum at x=10 mol%. An anomaly of character has been observed in all the properties of vanadyl doped glass systems, which gives a clear indication of mixed alkali effect. 相似文献
998.
V. Singh S. Watanabe T. K. Gundu Rao I.-J. Lee 《Applied physics. B, Lasers and optics》2011,104(4):1019-1027
Tricalcium aluminate doped with Eu3+ was prepared at furnace temperatures as low as 500°C by using the convenient combustion route and examined using powder X-ray
diffraction, scanning electron microscope and photoluminescence techniques. A room-temperature photoluminescence study showed
that the phosphors can be efficiently excited by UV/Visible region, emitting a red light with a peak wavelength of 616 nm
corresponding to the 5D0–7F2 transition of Eu3+ ions. The phosphor exhibits three thermoluminescence (TL) peaks at 195°C, 325°C and 390°C. Electron Spin Resonance (ESR)
studies were carried out to study the defect centres induced in the phosphor by gamma irradiation and also to identify the
defect centres responsible for the TL process. Room-temperature ESR spectrum of irradiated phosphor appears to be a superposition
of three distinct centres. One of the centres (centre I) with principal g-value 2.0130 is identified as O− ion while centre II with an axially symmetric principal values g
∥=2.0030 and g
⊥=2.0072 is assigned to an F+ centre (singly ionized oxygen vacancy). O− ion (hole centre) correlates with the TL peak at 195°C and the F+ centre (electron centre), which acts as a recombination centre, is also correlated to the 195°C TL peak. F+ centre further appears to be related to the high temperature peak at 390°C. Centre III is also assigned to an F+ centre and seems to be the recombination centre for the TL peak at 325°C. 相似文献
999.
J.-H. Yuan X.-Z. Sang C.-X. Yu L. Rao Y. Han G.-Y. Zhou S.-G. Li L.-T. Hou 《Applied physics. B, Lasers and optics》2011,105(4):685-688
Using the photonic crystal fiber (PCF) with the zero dispersion wavelength of 848 nm for the fundamental mode, the efficient
anti-Stokes signal generations from 645 to 543 nm are realized by pumping in the normal dispersion region. When the pump average
power increases from 200 to 500 mW, the output power of the anti-Stokes signal increases 8.46 times, the power ratio of the
anti-Stokes signal at 543 nm to the residual pump is calculated as 22.6:1, and the conversion efficiency η in the experiment can be up to 46%. Moreover, good optical beam quality of the anti-Stokes signal can be achieved. 相似文献
1000.
农产品外部品质无损检测中高光谱成像技术的应用研究进展 总被引:18,自引:0,他引:18
高光谱成像技术是一种传统图像及光谱的融合技术,可以同时获取研究对象的空间及光谱信息.由于图像数据能反映农产品的外部特征、表面缺陷及污斑情况,而光谱数据又可以对物体内部物理结构及化学成分进行分析.因此,近几年在农产品品质无损检测中引起越来越多的关注,成为一个研究热点.为了跟踪国内外的最新研究成果,对高光谱反射及荧光成像技术应用于农产品(水果、蔬菜、肉类、谷物等)的外部品质检测进行了分类综述,以期为高光谱技术在农业方面更广阔的应用提供参考. 相似文献