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Deterministic quantum communication using the symmetric W state

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science China(Physics,Mechanics & Astronomy) 2013年第10期56卷 1903-1908页

作者： TSAI Chia-Wei HWANG Tzonelih Smart Network System Institute at Institute for Information industry department of Computer science and Information Engineering National Cheng Kung University

This study proposes a new coding function for the symmetric W state. Based on the new coding function, a theoretical protocol of deterministic quanama communication （DQC） is proposed. The sender can use the proposed coding function to encode his/her message, and the receiver can perform the imperfect Bell measurement to obtain the sender＇s message. In comparison to the existing DQC protocols that also use the W class state, the proposed protocol is more efficient and also more practical within today＇s technology. Moreover, the security of this protocol is analyzed to show that any eavesdropper will be detected with a very high probability under both the ideal and the noisy quantum channel.

关键词： deterministic quantum communication symmetric W state imperfect Bell measurement

Transformations between Aeromagnetic Gradients in Frequency Domain

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Journal of Earth science 2010年第1期21卷 114-122页

作者：李海侠徐世浙余海龙魏巍房江奇 department of Earth sciences Zhejiang University department of Earth sciences Kunming University of Science and Technology Airborne Survey and Remote Sensing Center of Nuclear industry

Aeromagnetic gradients are often used to enhance details or add new insights for interpretation. The gradients may be measured or derived from the total field or from transformation between horizontal and vertical gradients. At present, vertical, horizontal, and triaxial aeromagnetic gradiometers are in operation throughout the world, while the first two are used more widely. Transformations between horizontal and vertical gradients are needed for acquiring three gradient components or for checking the validity of measured gradients. Transformation of potential field by fast Fourier transform technique in frequency domain is popularly used; however, when applied to transforming between gradients, there is a problem that needs resolving. Because those expressions of transform operators are undefined when u or v is equal to zero or u and v are simultaneously equal to zero （u is the frequency in x-direction, and v is the frequency in y-direction）, the operators cannot be sampled at these frequencies. Consequently, the transformation cannot be implemented by fast Fourier transform technique directly. In this article, shift sampling theory is employed for resolving this problem. Model test results show that the technique has good accuracy, and the real case of transformation indicates that the computed results agree better with the measured gradients; it demonstrates not only the effective- ness of method but also the reliability of the measured gradients.

关键词： frequency domain horizontal gradient vertical gradient transformation shift sampiing theory.

Synthesis of BSCFO Ceramics Membrane Using a Simple Complexing Method and Experimental Study of Sintering Parameters

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Journal of Materials science & Technology 2010年第10期26卷 914-920页

作者： Ensieh Ganji Babakhani Jafar Towfighi Khodadad Nazari Gas department Research Institute of Petroleum Industry (RIPI) Chemical Engineering department Engineering FacultyUniversity of Tarbiat Modares Chemical and Petrochemical department Research Institute of Petroleum Industry (RIPI)

A new complexing agent Ethylene Diamine N,N,N,N-Tetra N-Acetyl Diamine（EDTNAD）,was used for Ba0.5Sr0.5Co0.8Fe0.2O3-δ（BSCFO） *** chemicals such as ammonia,nitric acid and citric acid were eliminated in comparison to the commonly used EDTA *** agent makes complexing synthesis method a single step and causes more homogeneity in the liquid and solid *** sintering process was studied at temperatures between 1000 to 1200℃,heating-cooling rates of 1,2,5,10℃/min and dwell time of 2,5,10 and 15 ***-sintered membranes were investigated by X-ray diffraction （XRD）,scanning electron microscopy （SEM）,and density *** the SEM images and X-ray diffraction of the BSCFO disks,it could be seen that above 1100℃,crystal intensity decreased,and melting and deformation of the disk *** results show that in restricted temperature range,1000-1100℃,10% temperature increase leads to about a 4.5% density increase but a 200% increase in dwell time leads to about a 4% density *** could be concluded that the effect of temperature on grain growth,porosity and density is more than that of dwell *** also showed that the heating-cooling rate has no significant effect on grain size and density.

关键词： BSCFO Membrane Sintering grain size Perovskite

Structural characterization of steam-heat treated Tectona grandis wood analyzed by FT-IR and 2D-IR correlation spectroscopy

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Chinese Chemical Letters 2015年第2期26卷 221-225页

作者： Ming-Yu Li Shi-Chao Cheng Dan Li Shen-Nan Wang An-Min Huang Su-Qin Sun Research Institute of Wood industry Chinese Academy of Forestry department of Wood science and Technology Beijing Forestry University department of Chemistry Tsinghua University

The properties of wood can be improved through steam-heat *** are many studies about mechanical properties of steam-heat treated wood,but very few studies are on the aspects of chemical *** this study,FT-IR spectra combined with SD-IR spectra,correlation coefficients and 2DIR spectra are employed to analyze the chemical modifications of teak[Tectona grandis L.F.） wood during steam-heat treatment under treatment temperatures from 120 ℃ to 220 ℃ at intervals of 20 ℃.Acetic acid,which is produced during steam-heat treatment,acts as a catalyst of condensation and degradation reactions of wood *** changes of wood components are more and more intense with increasing the treatment *** sensitivity of wood samples to thermal perturbation rises initially with increasing treatment temperature before falling *** steam-heat treated wood under180℃ is the most sensitive.

关键词： Teak wood Steam-heat treatment FT-IR spectroscopy The correlation coefficients 2D-IR spectroscopy

Electron-leakage-related low-temperature light emission efficiency behavior in GaN-based blue light-emitting diodes

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Journal of Semiconductors 2014年第4期35卷 83-86页

作者：闫大为李丽莎任舰王福学杨国锋肖少庆顾晓峰 Key Laboratory of Advanced Process Control for Light industry (Ministry of Education) Department of Electronic Engineering Jiangnan University department of science Jiangnan University

The typical light emission efficiency behaviors of InGaN/GaN multi-quantum well （MQW） blue light- emitting diodes （LEDs） grown on c-plane sapphire substrates are characterized by pulsed current operation mode in the temperature range 40 to 300 K. At temperatures lower than 80 K, the emission efficiency of the LEDs decreases approximately as an inverse square root relationship with drive current. We use an electron leakage model to explain such efficiency droop behavior; that is, the excess electron leakage into the p-side of the LEDs under high forward bias will significantly reduce the injection possibility of holes into the active layer, which in turn leads to a rapid reduction in the radiative recombination efficiency in the MQWs. Combining the electron leakage model and the quasi-neutrality principle in the p-type region, we can readily derive the inverse square root dependent function between the light emission efficiency and the drive current. It appears that the excess electron leakage into the p-type side of the LEDs is primarily responsible for the low-temperature efficiency droop behavior.

关键词： gallium nitride light-emitting diode emission efficiency electron leakage

Local structure of oxygen-deficient Yttrium oxide

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Chinese Physics C 2013年第9期37卷 89-93页

作者：程学瑞代海洋戚泽明王玉银张国斌 department of Technology and Physics Zhengzhou University of Light Industry National Synchrotron Radiation Laboratory University of Science and Technology of China

Yttrium oxide thin films have been deposited on Si （100） substrate by using pulsed laser deposition （PLD） method. X-ray diffraction （XRD）, hard and soft X-ray absorption spectroscopy （XAFS） are employed to investigate the origin of oxygen vacancies and their influence on the structure and atomic distributions. The XRD results indicate that the Y203 thin films strongly orient the （111） axis of the cubic structure. Analyses on the Y K-edge extended X-ray absorption fine structures reveal that the coordination number of Y atoms decreases and the bond length of Y-O contracts due to the loss of oxygen atoms. The X-ray absorption near edge structure analysis together with a theoretical approach further confirms the oxygen vacancies formation and their possible location.

关键词： X-ray absorption spectroscopy oxygen vacancy

Progressive identification of lateral nonlinear unsteady aerodynamics from wind tunnel test data

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science China(Information sciences) 2019年第10期62卷 197-199页

作者： Shuang HU Jihong ZHU Wei YANG department of Computer science and Technology Tsinghua University Chengdu Aircraft Design and Research Institute Aviation Industry Corporation of China

Dear editor,Modern aircrafts have been increasingly demanded to extend the flight envelop to high *** super maneuverability at post-stall angles of attack has become the dominated design goal for advanced combat aircrafts. In this case, the aerodynamic response will present strong nonlinearity and unsteadiness. The conventional aerodynamic derivative model could not be applicable any more.

关键词： pro Progressive identification of lateral nonlinear unsteady aerodynamics from wind tunnel test data

Study on Kinetics of Natural Rubber Vulcanization by S/La(DiPDP)_3

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Journal of Rare Earths 2007年第4期25卷 396-400页

作者：林新花刘清亭陈朝晖王迪珍 College of Materials science and Engineering South China University of Technology department of Chemical Engineering Guangdong Industry Technical College Guangzhou 510300 China

Kinetics of natural rubber （NR） vulcanization by lanthanum O, O＇-diisopropyldithiophosphate [ La（DiPDP）3 ] was studied. La（DiPDP）3 had remarkable accelerating effect on the vulcanization of NR. The rate constant k6 of the reaction that turned polysulphidic cross-links into the modified main chain was higher than that of desulfuration reaction of polysulfidic cross-links （k3 ）. The activation energies （Ea2, Ea3, and Ea6） of the formation, desulfuration, and decomposition of polysulfidic cross-links were 87.57,102.34, and 95.01 kJ · mol^-1, respectively. Activation energy （Eas） of the reaction that turned the cross-link precursors into the modified main chain was 82.67 kJ · mol^-1. It could be concluded that the proportion of polysulphidic cross-links was higher than mono- and di- sulphidic cross-links during induction and curing periods, mono- and di- sulphidic cross-links increased as curing temperature rose. In the temperature range of 140 - 160 ℃, the amounts of polysulphidic cross-links were similar. However, over 160℃, mono- and di- sulphidic cross-links increased rapidly. Moreover, cross-link density of the vulcanizates was determined from the equilibrium-swelling data. A chemical probe detected the concentration of polysulphidic cross-links of vulcanizates. The change trend of the results predicated from equation corresponded to that of the experimental results.

关键词： vulcanization kinetics natural robber lanthanum O, O'-diisopropyldithiophosphate rare earth accelerator

Synthesis and electrochemical properties of Th-doped LiMn_2O_4 powders for lithium-ion batteries

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Rare Metals 2006年第Z1期25卷 58-61页

作者： LI Chao FAN Yanliang LI Shuzhong XIE Bing BI Lei YANG Shuting department of Applied Chemistry College of Material Science and Chemical Engineering Zhengzhou Institute of Light Industry Zhengzhou 450002 China Engineering Research Centre for New Power Source Materials of Henan Province Xinxiang 453002 China Department of Applied Chemistry College of Material Science and Chemical Engineering Zhengzhou Institute of Light Industry Zhengzhou 450002 China Engineering Research Centre for New Power Source Materials of Henan ProvinceXinxiang 453002 China Department of Applied Chemistry College of Material Science and Chemical Engineering Zhengzhou Institute of Light Industry Zhengzhou 450002 China Department of Applied Chemistry College of Material Science and Chemical Engineering Zhengzhou Institute of Light Industry Zhengzhou 450002 China Department of Chemical Engineering College of Chemistry and Environmental Science Henan Normal University Xinxiang 453002 China

To improve the cycle performance of eco-friendly and cost-effective spinel LiMn2O4 as the Li secondary batteries, the Th-doped LiThxMn1-xO4 spinel powers were synthesized by solid-state method. The starting materials, Li2CO3, MnO2 and Th(NO3)4·4H2O, were mixed uniformly using a traditional ball milling, which resulted in a uniform particle size distribution in the mixed powers. Tests of X-ray diffraction, SEM, impedance spectra and charge-discharge were carried out for LiThxMn1-xO4 cathode materials. Results show that the synthesized LiTh0.01Mn1.99O4 material exhibits standard spinel structure, regular particle morphology and excellent property of charge-discharge for big current. The capacity retention of the material modified by doping Th is more than 85.1% of the first discharge specific capacity of 111.5 mAh·g-1 after 20 cycles at the current rate 1C, while the pristine LiMn2O4 is only 57% of the first discharge specific capacity of 110.2 mAh·g-1 after the same cycles at the same current rate.

关键词： lithium ion batteries Th-doped electrochemical properties AC impedance