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Optimal phase estimation with photon-number difference measurement using twin-Fock states of light

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Chinese Physics B 2019年第12期28卷 82-87页

作者： JH xu J z Wang A X Chen y Li G R Jin Key Laboratory of Optical Field Manipulation of zhejiang Province and Physics Department of zhejiang Sci-Tech University Hangzhou 310018China Beijing Computational Science Research Center.Beijing 100193 China

Quantum phase measurement with multiphoton twin-Fock states has been shown to be optimal for detecting equal numbers of photons at the output ports of a Mach–zehnder interferometer(i.e., the so-called single-fringe detection), since the phase sensitivity can saturate the quantum Cramér–Rao lower bound at certain values of phase shift. Here we report a further step to achieve a global phase estimation at the Heisenberg limit by detecting the particle-number difference(i.e., the ?_z measurement). We show the role of experimental imperfections on the ultimate estimation precision with the six-photon twin-Fock state of light. Our results show that both the precision and the sensing region of the ?_z measurement are better than those of the single-fringe detection, due to combined contributions of the measurement outcomes. We numerically simulate the phase estimation protocol using an asymptotically unbiased maximum likelihood estimator.

关键词： foundations of quantum mechanics measurement theory nonclassical interferometry

Effects of Cryoprotective Agents on the Bovine Articular Chondrocyte Viability

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Chemical Research in Chinese Universities 2002年第2期18卷 109-112页

作者： X.xu z.F.Cui Department of Engineering Science Oxford UniversityOxfordOX13PJUK

Cryopreservation is the process of choice for long term preservation of cells and tissues. In this study, the effects of cryoprotective agents, dimethyl sulfoxide(DMSO), glycerol and 1,2 propanediol on the bovine articular chondrocyte viability were examined experimentally. The CPA was added at the concentrations of 0 6, 0 9, 1 2 and 1 5 mol/L and at 4 ℃ and 37 ℃ and removed at 37 ℃ in one step. CPA stepwise addition and removal at 0 6 and 1 2 mol/L and at 37 ℃ was also tested as an alternative protocol. Cell volume excursion during DMSO addition and removal was estimated and correlated well with cell survival rates. Solution makeup affects cell survival rate and a stepwise protocol can improve the cell survival rates significantly.

关键词： Cryoprotective agent Chondrocyte Cell viability Cartilage

Electrode Modifications for Polymer Light-Emitting Electrochemical Cells

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稀有金属材料与工程 2006年第A3期35卷 600-602页

作者： z y zhong y D Jiang W z Li X yang School of Optoelectronic Information University of Electronic Science and Technology of China Chengdu 610054 China

The influence of different modification methods on the surface properties of indium-tin-oxide (ITO) electrodes were investigated by measurements of chemical composition,surface roughness,sheet resistance,contact angle and surface free *** results demonstrate that oxygen plasma treatment more effectively optimizes the surface properties of ITO electrodes compared with the other ***,the polymer light-emitting electrochemical cells (PLECs) with the differently treated ITO substrates as device electrodes were fabricated and *** is found that oxygen plasma treatment on the ITO electrode enhances injection current,luminance and efficiency,thereby improves the device characteristics of the PLECs.

关键词： electroluminescene polymer light-emitting electrochemical cells electrode modifications device performance

A HOMOTOPy METHOD OF SWITCHING SOLUTION BRANCHES AT THE PITCHFORK BIFURCATION POINT

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Journal of Computational Mathematics 2001年第3期19卷 299-308页

作者： Cong, y.-H. zhu, z.-y. College of Mathematical Sciences Shanghai Teachers University Shanghai 200234 China

Provides information on a study which proposed a continuation method for switching solution branches at a pitchfork point. Problem of the standard pitchfork; Information on the systems of equations; Numerical examples... 详细信息

关键词： homotopy method switching solution branches pitchfork point

Synthesis of self-assembled nanorod vanadium oxide bundles by sonochemical treatment

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Journal of Natural Gas Chemistry 2009年第3期18卷 312-318页

作者： y.H.Taufiq-yap y.C.Wong z.zainal M.z.Hussein Centre of Excellence for Catalysis Science and Technology Faculty of ScienceUniversiti Putra Malaysia Department of Chemistry Faculty of ScienceUniversiti Putra Malaysia

Self-assembled nanorod of vanadium oxide bundles were synthesized by treating bulk V2O5 with high intensity sonochemical technique. The synthesized materials were characterized by X-ray diffraction （XRD）, scanning electron microscope （SEM）, transmission electron microscope （TEM） and temperature-programmed reduction （TPR） in H2. Catalytic behaviour of the materials over anaerobic n-butane oxidation was studied through temperature-programmed reaction （TPRn）. Catalytic evaluation of the sonochemical treated V2O5 products was also studied on microreactor. XRD patterns of all the vanadium samples were perfectly indexed to V2O5. The morphologies of the nanorod vanadium oxides as shown in SEM and TEM depended on the duration of the ultrasound irradiation. Prolonging the ultrasound irradiation duration resulted in materials with uniform, well defined shapes and surface structures and smaller size of nanorod vanadium oxide bundles. H2-TPR profiles showed that larger amount of oxygen species were removed from the nanorod V2O5 compared to the bulk. Furthermore, the nanorod vanadium oxide bundles, which were produced after 90, 120 and 180 min of sonochemical treatment, showed an additional reduction peak at lower temperature （-850 K）, suggesting the presence of some highly active oxygen species. TPRn in n-butane/He over these materials showed that the nanorod V2O5 with highly active oxygen species showed markedly higher activity than the bulk material, which was further proven by catalytic oxidation of n-butane.

关键词： nanorod vanadium oxide sonochemical treatment butane oxidation

Optimizing large optical contrast in Ge-Se-Te films via high-throughput method

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Progress in Natural Science:Materials International 2025年第01期 222-228页

作者： Qiqi Chen Guoxiang Wang zijun Liu yixiao Gao Chenjie Gu Tiefeng xu Xiang Shen yimin Chen Laboratory of Infrared Material and Devices & Key Laboratory of Photoelectric Materials and Devices of zhejiang Province Advanced Technology Research InstituteNingbo University Department of Microelectronic Science and Engineering School of Physical Science and Technology Ningbo University Ningbo Solartrum Co.Ltd.

Chalcogenide phase-change materials（PCMs） have attracted great attentions due to their potential applications in reconfigurable photonic devices. The Ge2Sb2Te5and GeTe PCMs exhibit significant difference in refractive index（Δn） between amorphous and crystalline states, but they suffer from high optical loss. The binary Sb2S3and Sb2Se3PCMs, however, show low optical loss but small Δn. This encourages us to develop the novel materials,which are desired to combine large Δn and low optical loss. Instead of traditional trial-and-error screening method, we here used an efficient high-throughput method to optimize the PCMs' candidates for reconfigurable photonic devices in Ge-Se-Te chalcogenides. The crystallization temperature and difference in optical bandgap were detected, and then the component of Ge25Se7Te68, which also exhibits ultralow optical loss of 1.2 × 10-6（in amorphous state） and large Δn of 1.32 at 1550 nm, was optimized. This Te-rich Ge-Se-Te film can be a candidate for the applications of programmable reconfigurable photonic circuits.

关键词：

SyNTHESIS　AND　CHARACTERIzATION　OF　METAL　COMPLEXES　DERIVED　FROM　POTASSIUM　3－（BENzOTRIAzOLE1－CARBONyLMETHyL）－DITHIOCARBAzATE

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Chinese Chemical Letters 1995年第11期6卷 1009-1012页

作者： xu, PF Wu, z Lanzhou Univ Dept Chem Lanzhou 730000 Peoples R China Cent Res Inst Bldg & Construct MMI Beijing 100088 Peoples R China

The preparation and characterization of some divalent metal ion M (Ⅱ)complexes derived from potassium 3-(benzotriazole-1-carbonylmethyl)-dithiocar bazate (BCDHK) is reported. Thesolid complexes of the composition ML· nH2Oand ML2·2H2O (M=Ph(Ⅱ), UO2(Ⅱ)), have been characterized on the basis of elemental analyses,IR, UV and TGA.

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Effect of Carbon Nanotube Orientation on Mechanical Properties and Thermal Expansion Coefficient of Carbon Nanotube-Reinforced Aluminum Matrix Composites

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Acta Metallurgica Sinica(English Letters) 2014年第5期27卷 901-908页

作者： z.y.Liu B.L.Xiao W.G.Wang z.y.Ma School of Materials Science and Engineering Dalian University of Technology Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences School of Mechanical Engineering Liaoning Shihua University

Carbon nanotube-reinforced 2009Al （CNT/2009Al） composites with randomly oriented CNTs and aligned CNTs were fabricated by friction stir processing （FSP） and FSP-rolling, respectively. The CNT/2009A1 composites with aligned CNTs showed much better tensile properties at room temperature and elevated temperature compared with those with the randomly oriented CNTs, which is mainly attributed to larger equivalent aspect ratio of the CNTs and avoidance of preferential fracture problems. However, much finer grain size was not beneficial to obtaining high strength above 473 K. The aligned CNTs resulted in tensile anisotropy, with the best tensile properties being achieved along the direction of CNT aligning. As the off-axis angle increased, the tensile properties were reduced due to the weakening of the load transfer ability. Furthermore, aligned CNTs resulted in much lower coefficient of thermal expansion compared with randomly oriented CNTs.

关键词： Carbon nanotubes Metal matrix composites Mechanical properties Coefficient of thermalexpansion Friction stir processing

Quantifying Tectonic and Geomorphic Interpretations of Thermochronometer Data with Inverse Problem Theory

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Communications in Computational Physics 2011年第1期9卷 129-146页

作者： G.Bao y.Dou T.A.Ehlers P.Li y.Wang z.xu Department of Mathematics Michigan State UniversityEast LansingMI 48824USA Institut fuer Geowissenschaften Universitat TuebingenGermany Department of Mathematics Purdue UniversityWest LafayetteIN 47907USA Department of Mathematics Fudan UniversityShanghaiChina Department of Mathematics Harbin Institute of TechnologyHarbinChina

Thermochronometer data offer a powerful tool for quantifying a wide range of geologic processes,such as the deformation and erosion of mountain ranges,topographic evolution,and hydrocarbon *** increasing interest to quantify a wider range of complicated geologic processes,more sophisticated techniques are *** paper is concerned with an inverse problem method for interpreting the thermochronometer data *** novel models are proposed to simulate the crustal thermal fields and paleo mountain topography as a function of tectonic and surface *** is a heat transport model that describes the change of temperature of rocks;while the other is surface process model which explains the change of mountain *** computational algorithms are presented for solving the inverse problem of the coupled system of these two *** model successfully provides a new tool for reconstructing the kinematic and the topographic history of mountains.

关键词： Thermochronology heat equations inverse problem variational method iterative method surface processes