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Universal bound on sampling bosons in linear optics and its computational implications

National Science Review 2019年第4期6卷 719-729页

作者： Man-Hong Yung xun gao Joonsuk Huh Shenzhen Institute for Quantum Science and Engineering and Department of Physics Southern University of Science and Technology Shenzhen Key Laboratory of Quantum Science and Engineering Southern University of Science and Technology Central Research Institute Huawei Technologies Center for Quantum Information Institute for Interdisciplinary Information SciencesTsinghua University Department of Chemistry Sungkyunkwan University

In linear optics, photons are scattered in a network through passive optical elements including beam splitters and phase shifters, leading to many intriguing applications in physics, such as Mach–Zehnder interferometry, the Hong–Ou–Mandel effect, and tests of fundamental quantum mechanics. Here we present the fundamental limit in the transition amplitudes of bosons, applicable to all physical linear optical networks. Apart from boson sampling, this transition bound results in many other interesting applications,including behaviors of Bose–Einstein condensates(BEC) in optical networks, counterparts of Hong–Ou–Mandel effects for multiple photons, and approximating permanents of matrices. In addition,this general bound implies the existence of a polynomial-time randomized algorithm for estimating the transition amplitudes of bosons, which represents a solution to an open problem raised by Aaronson and Hance(Quantum Inf Comput 2012; 14: 541–59). Consequently, this bound implies that computational decision problems encoded in linear optics, prepared and detected in the Fock basis, can be solved efficiently by classical computers within additive errors. Furthermore, our result also leads to a classical sampling algorithm that can be applied to calculate the many-body wave functions and the S-matrix of bosonic particles.

关键词： boson sampling quantum optics quantum supremacy linear optics computational complexity

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Jet Vectoring Control Using a Novel Synthetic Jet Actuator

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Chinese Journal of Aeronautics 2007年第3期20卷 193-201页

作者： LUO Zhen-bing XIA Zhi-xun XIE Yong-gao College of Aerospace and Materials Engineering National University of Defense Technology Changsha 410073 China

A primary air jet vectoring control system with a novel synthetic jet actuator （SJA） is presented and simulated numerically. The results show that, in comparison with an existing traditional synthetic jet actuator, which is able to perform the duty of either ＂push＂ or ＂pull＂, one novel synthetic jet actuator can fulfill both ＂push＂ and ＂pull＂ functions to vector the primary jet by shifting a slide block inside it. Therefore, because the new actuator possesses greater efficiency, it has potentiality to replace the existing one in various appli- cations, such as thrust vectoring and the reduction of thermal signature. Moreover, as the novel actuator can fulfill those functions that the existing one can not, it may well be expected to popularize it into more flow control systems.

关键词： jet vectoring control synthetic jet actuator slide block flow control

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Characteristics of ion debris from laser-produced tin plasma and mitigation of energetic ions by ambient gas

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Science China(Physics,Mechanics & Astronomy) 2012年第3期55卷 392-395页

作者： YingBo Sun JingQuan Lin xun gao ZhenMing Zhao Changchun Univ Sci & Technol Sch Sci Changchun 130022 Peoples R China

Extreme ultraviolet lithography is most promising for the next generation lithography. However, debris from laser-produced plasma, particularly energetic ions, severely decreases the lifetime of extreme ultraviolet optics. We measured the characteris- tics of ions from tin plasma by the time of flight method with a frequency-doubled Nd： YAG laser at the intensity of 3.5x1010 W/cm2 （532 nm, 8 ns）. Our measurement shows that the maximum and peak of tin ions energies from plasma under the above experimental parameters are about 4.2 and 1.8 keV, respectively. Moreover, it is found that kinetic energy angular distribution of tin ions can be fitted by cos0.8（θ）, where θ is the angle with respect to the target normal. We also investigated the mitigation effect of argon, helium gases to the tin ions, and found that tin ions from the plasma can be mitigated effectively at the pressure -38 mTorr for argon or -375 mTorr for helium, respectively.

关键词： extreme ultraviolet source tin plasma ion ambient gas

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Experimental study of Forrelation in nuclear spins

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Science Bulletin 2017年第7期62卷 497-502页

作者： Hang Li xun gao Tao Xin Man-Hong Yung Guilu Long State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics Tsinghua University Beijing 100084 China Collaborative Innovation Centre of Quantum Matter Beijing 100084 China Centre for Quantum Information Institute for Interdisciplinary Information Sciences Tsinghua University Beijing 100084 China Institute for Quantum Science and Engineering and Department of Physics Southern University of Science and Technology Shenzhen 518055 China

Correlation functions are often employed to quantify the relationships among interdependent variables or sets of ***,a new class of correlation functions,called FORRELATION,has been introduced by Aaronson and Ambainis for studying the query complexity of quantum *** was found that there exists a quantum query algorithm solving 2-fold FORRELATION problems with an exponential quantum speedup over all possible classical means,which represents essentially the largest possible separation between quantum and classical query *** we report an experimental study probing the2-fold and 3-fold FORRELATIONS encoded in nuclear *** major experimental challenge is to control the spin fluctuation to within a threshold value,which is achieved by developing a set of optimized GRAPE pulse ***,our small-scale implementation indicates that the quantum query algorithm is capable of determining the values of FORRELATIONS within an acceptable accuracy required for demonstrating quantum supremacy,given the current technology and in the presence of experimental noise.

关键词： Forrelation Query complexity Nuclear magnetic resonance Gradient ascent pulse engineering

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Synthesis and Crystal Structure of the Copper Complex {[Cu(CH_3COO)_2(bbtz)](H_2O)_2}_n

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Chinese Journal of Structural Chemistry 2005年第10期24卷 1129-1132页

作者： ZHANG Yong ZHANG Yu-Mei LIU xun-gao LI Bao-Long Key Laboratory of Organic Synthesis of Jiangsu Province College of Chemistry and Chemical Engineering Suzhou University Suzhou 215123 China

The new copper complex { [Cu（CH3COO）2（bbtz）]（H2O）2 }, 1 （bbtz = 1,4-bis（ 1,2,4- triazol-1-ylmethyl）benzene） was synthesized and the structure was determined by single-crystal X-ray diffraction. Crystal data： C16H22CuN6O6, monoclinic, space group P21/n, a = 12.589（5）, b = 6.455（2）, c = 12.677（5） A, β= 98.748（9）°, V= 1018.2（7） A^3, Mr = 457.95, Z = 2, Dc= 1.494 g/cm^3, F（000） = 474, μ = 1.118 mm^-1, R = 0.0463 and wR = 0.0939 for 1971 observed reflections with I 〉 2σ（I）. The crystal structure of 1 is a one-dimensional chain via the bridging flexible ligand bbtz.

关键词： crystal structure copper complex triazole ligand synthesis

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Gas chromatography-mass spectrometry method for determination ofβ-propiolactone in human inactivated rabies vaccine and its hydrolysis analysis

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Journal of Pharmaceutical Analysis 2018年第6期8卷 373-377页

作者： Shuo Lei xun gao Yang Sun Xiangyong Yu Longshan Zhao School of Pharmacy Shenyang Pharmaceutical UniversityShenyang 110016China Liaoning Medical Device Test Institute Shenyang 110179China Shenyang Wellwolf Pharmaceutical Science and Technology Co.Ltd Shenyang 110022China

A simple method was established for the determination of β-propiolactone(BPL) in human inactivated rabies vaccine by gas chromatography-mass spectrometry(GC-MS). The determination was performed on an Agilent HP-INNOWAX(30 m ? 0.32 mm i.d., 0.25 mm) capillary column at the temperature of 80 °*** ionization(ESI) was used by selective ion detection at m/z 42. The temperature for ESI source and inlet was set at 230 °C and 200 °C, respectively. Helium was used as the carrier gas at a flow rate of 25.1 m L/min. The total run time was 8 min. Acetonitrile and other components in the sample did not interfere with the determination of BPL. The results showed good linearity of BPL in the range of0.50–10.01 μg/mL, with the limit of detection and the limit of quantification of 0.015 μg/mL and0.050 μg/mL, respectively. Satisfactory precision was achieved for the current developed method. The method was applied to detect 6 batches of vaccine samples, and the results indicated that the target analyte BPL was present in three batches of unpurified samples, but was not detected in the purified samples, indicating the test samples were qualified. The established method was proved to be simple,versatile and sensitive, which can meet the requirements of quality control of BPL in human inactivated rabies vaccine.

关键词： β-propiolactone Inactivated human rabies vaccine GC-MS Hydrolysis

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Analysis of the element content in poplar tree leaves by femtosecond laser-induced breakdown spectroscopy

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Science China(Physics,Mechanics & Astronomy) 2011年第11期54卷 1953-1957页

作者： MA Shuang gao xun GUO KaiMin KAHSAY Medhanie LIN JingQuan School of Science Changchun University of Science and Technology Changchun 130022 China International Joint Research Centerfbr Nanophotonics and Biophotonics Changchun University of Science and Technology Changchun 130022 China

Femtosecond laser-induced breakdown spectroscopy (fs-LIBS) is employed to analyze the element content in poplar tree leaves from four representative locations in Changchun City (Jingyue National Forest Park,JYP),Changchun University of Science and Technology (CUST),Casting Factory (CF) and Forging Factory (FF) of First Automobile Works (FAW) under identical experimental *** elements of N,P,K,Ca,Fe,Ti,Mn and Na are identified in the poplar tree leaves from the recorded spectrogram and the elemental content in the leaves is further obtained by applying free calibration method to the *** results show that the elements Ca and Fe in the poplar tree leaves from the CF area have the highest concentration in the four locations,which is a factor of 2.05 and 1.66 respectively to those of *** experiment demon-strates that fs-LIBS can be utilized to analyze element content in a sample and find new applications in the environmental detection.

关键词： femtosecond laser laser-induced breakdown spectroscopy poplar tree leaf quantitative analysis

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Strip flatness prediction of cold rolling based on ensemble methods

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Journal of Iron and Steel Research International 2024年第1期31卷 237-251页

作者： Wu-quan Yang Zhi-ting Zhao Liang-yu Zhu xun-yang gao Li Wang School of Mechanical and Power Engineering Shenyang University of Chemical TechnologyShenyang110142LiaoningChina

Aiming at the problem of insufficient prediction accuracy of strip flatness at the outlet of cold tandem rolling,the prediction performance of strip flatness based on different ensemble methods was studied and a high-precision prediction ensemble model of strip flatness at the outlet was ***,based on linear regression(LR),K nearest neighbors(KNN),support vector regression,regression trees(RT),and backpropagation neural network(BPN),bagging,boosting,and stacking ensemble methods were used for ensemble ***,three existing ensemble models,i.e.,random forest,extreme random tree(ET)and extreme gradient boosting,were used to conduct experiments and compare the *** research shows that bagging,boosting,and stacking three ensemble methods have the most significant improvement in the prediction accuracy of the regression trees model,which is increased by 5.28%,6.51%,and 5.32%,*** the same time,the stacking ensemble method improves both the simple model and the complex model,and the improvement effect on the simple base model is the greatest,which is 4.69%higher than that of the base model *** all of the ensemble models,the stacking ensemble model of level-1(ET,AdaBoost-RT,LR,BPN)paired with level-2(LR)was discovered to be the best model(EALB-LR)and can be further studied for industrial applications.

关键词： Tandem cold rolling Flatness prediction Machine learning Ensemble method

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Combined effects of ambient gas pressures and magnetic field on laser plasma expansion dynamics

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Plasma Science and Technology 2017年第1期19卷 79-84页

作者： Atif HUSSAIN xun gao Qi LI Zuoqiang HAO Jingquan LIN School of Science Changchun University of Science and Technology Changchun 130022 People＇s Republic of China

In this work,we investigated the influence of air gas pressures on the expansion features of nanosecond laser ablated aluminum plasma in the absence and presence of a nonuniform magnetic field using fast photography.A particular emphasis was given to the plume dynamics（shape,size） with the combined effects of ambient gas pressures and an external magnetic *** expansion,sharpening effect,and hemi-spherical structures of the aluminum plasma were observed without a magnetic field under different gas *** of the resulting plume images with the combined effects of air gas pressures and a magnetic field show significant changes,such as plume splitting,elliptical geometry changes,radial expansion,and plume ***,the total size of the plasma plume with a magnetic field was measured to be smaller than the plasma plume without a magnetic field at several background pressures.

关键词： magnetic field air pressure expansion plume front propagation

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Study on degradation kinetics of epalrestat in aqueous solutions and characterization of its major degradation products under stress degradation conditions by UHPLC-PDA-MS/MS

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Journal of Pharmaceutical Analysis 2019年第6期9卷 423-430页

作者： Hong Sun Suyan Liu xun gao Zhili Xiong Zhonggui He Longshan Zhao Shanxi Biosample Analysis Center Shanxi Health Vocational CollegeNo.100Wenjin StreetYuci DistrictJinzhong 030619PR China School of Pharmacy Shenyang Pharmaceutical UniversityNo.103Wenhua RoadShenyang 110016PR China

Drug stability is closely related to drug safety and needs to be considered in the process of drug production,package and *** investigate the stability of epalrestat,a carboxylic acid derivative,a reversed-phase high-performance liquid chromatography(RP-HPLC)method was developed in this study and applied to analyzing the degradation kinetics of epalrestat in aqueous solutions in various conditions,such as different pH,temperatures,ionic strengths,oxidation and *** calibration curve was A=1.6×10^5C–1.3×10^3(r=0.999)with the liner range of 0.5–24μg/mL,the intra-day and inter-day precision was less than 2.0%,as was the *** average accuracy for different concentrations was more than 98.5%,indicating that perfect recoveries were *** kinetic parameters such as degradation rate constants(k),activation energy(Ea)and shelf life(t0.9)under different conditions were calculated and *** results indicated that the degradation behavior of epalrestat was pH-dependent and the stability of epalrestat decreased with the rised irradiation and ionic strength;however,it was more stable in neutral and alkaline conditions as well as lower *** results showed that the degradation kinetics of epalrestat followed first-order reaction ***,the degradation products of epalrestat under stress conditions were identified by UHPLC-PDA-MS/MS,with seven degradation products being detected and four of them being tentatively identified.

关键词： Epalrestat RP-HPLC Degradation kinetics UHPLC-PDA-MS/MS Degradation products

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