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Journal of Rare Earths 2018年第6期36卷 594-602页

作者： ning Liu Jingyu Wang Fengying Wang jun Liu School of Environment and Safety Engineering North University of ChinaTaiyuan 030051China Key Laboratory of Coal Science and Technology Ministry of Education and Shanxi ProvinceTaiyuan University of TechnologyTaiyuan 030024China

A superior Ce-Ta-Sb composite oxide catalyst prepared using homogeneous precipitation method exhibited excellent deNOx efficiency and nearly 100% Nselectivity with broad operation temperature window and better resistance to higher space velocity, meanwhile strong resistance to HO and SO. This catalyst was systematically characterized using XRD, Nadsorption, SEM, TEM, XPS, ESR, Raman, H-TPR,NH3-TPD and in situ DRIFTS. There exists a synergistic effect between Ce, Ta and Sb species. It is further indicated that the prominent deNOx performance of the Ce3 Ta3 SbOx catalyst is attributed to the elevated Ce3+ concentrations, abundant active surface oxygen species, as well as surface acidity and reducibility,which is closely linked with the synergistic effect between Ce, Sb and Ta species. Results from DRIFTS reveal that the reaction mechanism of surface-adsorbed NH3 and NOspecies is linked to temperature,the L-H mechanism mainly occurs at low temperature(300 ℃). Overall,these findings indicate that Ce3 Ta3 SbOx is promising for NOpractical abatement.

关键词： Ce-Ta-Sb mixed oxides Homogeneous precipitation method NH_3-SCR Synergistic effect NO_x adsorbed species Rare earths

DNS Study on Volume Vorticity Increase in Boundary Layer Transition

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Transactions of Nanjing University of Aeronautics and Astronautics 2016年第3期33卷 252-259页

作者： Wang Yiqian Tang jie Liu Chaoqun Zhao ning College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics Department of Mathematics University of Texas at Arlington

The issue whether transition from laminar flow to turbulent flow on a flat plate should be characterized as a vorticity redistribution process or a vorticity increasing process is investigated by a high-order direct numerical simulation on a flat plate boundary *** local vorticity can either increase or decrease due to tilting and stretching of vortex filaments according to the vorticity transport equation while the total vorticity cannot be changed in a boundary layer flow in conforming to the Fppl theorem of total vorticity *** seemingly contradictory problem can be well resolved by the introduction of a new term:volume vorticity of a vorticity tube,defined as vorticity flux timed by the vorticity tube *** has been shown that,although vorticity flux must keep conserved,the total volume vorticity is significantly increased during boundary layer transition according to our direct numerical simulation(DNS)computation,which directly results from the lengthening(stretching and tilting)of vortex ***,the flow transition is a process with appreciable increase of volume vorticity,and cannot be only viewed as a vorticity redistribution process.

关键词： volume vorticity vorticity redistribution vorticity increase transition boundary layer

Tissue Extracts From Infarcted Myocardium of Rats in Promoting the Differentiation of Bone Marrow Stromal Cells Into Cardiomyocyte-like Cells

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Biomedical and Environmental Sciences 2008年第2期21卷 110-117页

作者： XIAO-ning LIU Oi YIN HAO ZHANG HONG ZHANG SHEN-jun ZHU YING-jie WEI SHENG-SHOU HU Key Laboratory of Cardiovascular Regenerative Medicine Ministry of Health and Department of Cardiovascular Surgery Cardiovascular Institute of Fuwai Hospital Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100037 China Department of Thoracicand Cardiovascular Surgery FirstAffiliated Hospital Wenzhou Medical College Wenzhou 325000 Zhejiang China

Objective To investigate whether cardiac tissue extracts from rats could mimic the cardiac microenvironment and act as a natural inducer in promoting the differentiation of bone marrow stromal cells （BMSCs） into cardiomyocytes. Methods Three kinds of tissue extract or cell lysate [infarcted myocardial tissue extract （IMTE）, normal myocardial tissue extract （NMTE） and cultured neonatal myocardial lysate （NML）] were employed to induce BMSCs into cardiomyocyte-like cells. The cells were harvested at each time point for reverse transcription-polymerase chain reaction （RT-PCR） detection, immunocytochemical analysis, and transmission electron microscopy. Results After a 7-day induction, BMSCs were enlarged and polygonal in morphology. Myofilaments, striated sarcomeres, Z-lines, and more mitochondia were observed under transmission electron microscope. Elevated expression levels of cardiac-specific genes and proteins were also confirmed by RT-PCR and immunocytochemistry. Moreover, IMTE showed a greater capacity of differentiating BMSCs into cardiomyocyte-like cells. Conclusions Cardiac tissue extracts, especially IMTE, can effectively differentiate BMSCs into cardiomyocyte-like cells.

关键词： Bone marrow stromal cells Cell differentiation Cardiac tissue extracts Myocardial infarction

Phase Separation and Transport Behavior in La_(0.67-x)Sm_xSr_(0.33)MnO_3 System

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Chemical Research in Chinese Universities 2005年第6期21卷 707-713页

作者： LIU ning YAN Guo-qing XU Su-jun Department of Physics Suzhou College Suzhou 23400 P. R. China Structure Research Laboratory Science and Technology University of China Hefei 230026 P. R. China

The magnetic behavior and the transport behavior of La0.67-x Smx Sr0.33 MnO3 （x = 0. 00, 0. 10, 0. 20, 0. 30, 0. 40, 0. 50 and 0. 60 ） systems were studied through measuring the M-T curves, electron spin resonance （ ESR ） curves and ρ-T curves. The samples exhibit a long-range ferromagnetic order when x = 0. 00, 0. 10, a cluster-spin glass state when x = 0. 20 and 0. 30, and an anti-ferromagnetic state at low temperatures when x = 0. 40, 0. 50 and 0. 60. The samples of x = 0. 30 and 0.40 show phase separation at temperatures above Te. The transport behavior of the sample of x = 0. 60 becomes abnormal when the doping is high, and an insulator-metal transition occurs near To and then a metal-insulator transition occurs, which rarely appears in an ABO3 structure. It is concluded that the magnetic and electric behavior changes of the systems depend on the extra magnetism and lattice distortion effect induced by Sm doping.

关键词： Magnetic structure Phase separation Transport behavior Colossal magnetoresistance effect

Unsteady supercritical/critical dual flowpath inlet flow and its control methods

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Chinese Journal of Aeronautics 2017年第6期30卷 1877-1884页

作者： jun LIU Huacheng YUAN Yunfei WANG ning GE College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Jiangsu Province Key Laboratory of Aerospace Power Systems Nanjing 210016China

The characteristics of unsteady flow in a dual-flowpath inlet, which was designed for a Turbine Based Combined Cycle（TBCC） propulsion system, and the control methods of unsteady flow were investigated experimentally and numerically. It was characterized by large-amplitude pressure oscillations and traveling shock waves. As the inlet operated in supercritical condition,namely the terminal shock located in the throat, the shock oscillated, and the period of oscillation was about 50 ms, while the amplitude was 6 mm. The shock oscillation was caused by separation in the diffuser. This shock oscillation can be controlled by extending the length of diffuser which reduces pressure gradient along the flowpath. As the inlet operated in critical condition, namely the terminal shock located at the shoulder of the third compression ramp, the shock oscillated,and the period of oscillation was about 7.5 ms, while the amplitude was 12 mm. At this condition,the shock oscillation was caused by an incompatible backpressure in the bleed region. It can be controlled by increasing the backpressure of the bleed region.

关键词： Airbreathing hypersonic vehicle Dual flowpath inlet Terminal shock oscillation Turbine based combined cycle Unsteady flow

Dropout training for SVMs with data augmentation

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Frontiers of Computer Science 2018年第4期12卷 694-713页

作者： ning CHEN jun ZHU Jianfei CHEN Ting CHEN MOE Key lab of Bioinformatics Bioinformatics Division and Center for Synthetic and Systems Biology TNLIST Tsinghua University Beijing 100084 China State Key Lab of Intelligent Technology and Systems Department of Computer Science and Technology Tsinghua University Beijing 100084 China

Dropout and other feature noising schemes have shown promise in controlling over-fitting by artificially corrupting the training data. Though extensive studies have been performed for generalized linear models, little has been done for support vector machines （SVMs）, one of the most successful approaches for supervised learning. This paper presents dropout training for both linear SVMs and the nonlinear extension with latent representation learning. For linear SVMs, to deal with the intractable expectation of the non-smooth hinge loss under corrupting distributions, we develop an iteratively re-weighted least square （IRLS） algorithm by exploring data augmentation techniques. Our algorithm iteratively minimizes the expectation of a re- weighted least square problem, where the re-weights are analytically updated. For nonlinear latent SVMs, we con- sider learning one layer of latent representations in SVMs and extend the data augmentation technique in conjunction with first-order Taylor-expansion to deal with the intractable expected hinge loss and the nonlinearity of latent representa- tions. Finally, we apply the similar data augmentation ideas to develop a new IRLS algorithm for the expected logistic loss under corrupting distributions, and we further develop a non-linear extension of logistic regression by incorporating one layer of latent representations. Our algorithms offer insights on the connection and difference between the hinge loss and logistic loss in dropout training. Empirical results on several real datasets demonstrate the effectiveness of dropout training on significantly boosting the classification accuracy of both linear and nonlinear SVMs.

关键词： dropout SVMs logistic regression data aug- mentation iteratively reweighted least square

Controlled Teleportation of Multi-qutrit Quantum Information by Swapping Entanglement

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Communications in Theoretical Physics 2008年第2期49卷 338-342页

作者： YANG jie LIU jun Key Laboratory of Optoelectronic Information Acquisition ＆ Manipulation of Ministry of Education of China Key Laboratory of Information Material ＆ Device of Anhui Province School of Physics ＆ Material Science Anhui University Hefei 230039 China

We present a scheme for teleporting multi-qutrit quantum information from a sender to a receiver via the control of many agents in a network. Agents＇s control parameters are obtained via quantum entanglement swapping. In our scheme, Zhang and Man＇s QSS protocol [Phys. Rev. A 72 （2005） 022303] based on Bell-state entanglement swapping is generalized to a qutrit case. Our scheme owns the advantage of having higher code capacity and better security than the work [Commun. Theor. Phys. 44 （2005） 847] on controlled teleportation for multi-qubit.

关键词： controlled teleportation multi-qutrit quantum information entanglement swapping

Penn State Worry Questionnaire:structure and psychometric properties of the Chinese version

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第3期10卷 211-218页

作者： jie ZHONG Chun WANG jie LI jun LIU Department of Psychology Peking University Beijing 100871 China Beijing Anding Hospital Beijing 100088 China

The Penn State Worry Questionnaire(PSWQ) is a measure of worry phenomena and has been demonstrated valid in cross-cultural populations. The present study examined the factor structure and psychometric properties of the Chinese version of PSWQ(Ch-PSWQ) in a Chinese college sample(n=1243). Exploratory factor analysis of the Ch-PSWQ revealed a two-factor solution(engagement of worry and absence of worry). Confirmatory factor analysis and model comparison supported that the model of one factor with method effect provided the best fit to the data. The Ch-PSWQ and its factors evidenced good internal consistency and both convergent and discriminate validity. The present study supports the opinion that the second factor of PSWQ not only contains the component of evaluating pathological worry,but also might represent other traits.

关键词： Worry Penn State Worry Questionnaire (PSWQ) Construct Reliability Validity

Propagating Optical Phonon Modes and Their Electron-Phonon Interaction Hamiltonians in Asymmetric Wurtzite Nitride Semiconductor Quantum Wells

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Communications in Theoretical Physics 2006年第5期45卷 935-944页

作者： ZHANG Li SHI jun-jie Department of Mechanism and Electron Panyu Polytechnic Panyu 511483 China State Key Laboratory for Mesoscopic Physics and School of Physics Peking University Beijing 100871 China

Within the framework of the dielectric continuum model and Loudon ＇s uniaxial crystal model, the properties of frequency dispersion of the propagating （PR） optical phonon modes and the coupling functions of electron-PR phonons interaction in an asymmetrical wurtzite quantum well （QW） are deduced and analyzed via the method of electrostatic potential expanding. Numerical calculation on an asymmetrical Alo.25Gao.75N/GaN/*** wurtzite QW were performed. The results reveal that there are infinite branches of PR phonon modes in the systems. The behaviors of frequency forbidden of PR modes in the asymmetric QWs have been clearly observed. The mathematical and physical origins for these features have been analyzed in depth. The PR optical phonon branches have been distinguished and labelled reasonably in terms of the oscillating properties of the PR modes in the well-layer material. Moreover, the amplitudes and frequency properties of the electron-PR modes coupling functions in the barrier and well materials have also been analyzed from both of the mathematical and physical viewpoints.

关键词： propagating modes electron-phonon coupling asymmetrical wurtzite heterostructure

Clinical effects of Xingnao Kaiqiao acupuncture on neurological impairment following cerebral infarction

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Neural Regeneration Research 2008年第3期3卷 272-275页

作者： jie Xiong Lina ning Jinling Bian jun Li junfeng Xu Zhilong Zhang Jiakui Guo YadongLi Xuemin Shi Department of Traditional Chinese Medcine Rehabilitation and Physiotherapy the Affiliated Hospital of Medical College of Chinese Armed Police Forces Tianjin 300162 China The Specialty of Acupuncture and Manipulation Tianjin University of Traditional Chinese Medicine Tianjin 300193 China Department of Acupuncture the First Affiliated Hospital of Tianjin University of Traditional Chinese Medicine Tianjin 300193 China Department of Acupuncture Tianjin Traditional Chinese Medicine Hospital Tianjin 300140 China Department of Acupuncture the Second Affiliated Hospital of Tianjin University of Traditional Chinese Medicine Tianjin 300150 China

BACKGROUND： Although the curative effects of acupuncture have been confirmed by various treatments of cerebral infarction, few studies have investigated when acupuncture can attain the best clinical effect. OBJECTIVE： Four different time points were selected for acupuncture treatment of cerebral infarction to evaluate the appropriate time course for Xingnao Kaiqiao therapy in terms of improved neurological function. DESIGN： Controlled observation. SETTING： Department of Traditional Chinese Medicine Rehabilitation and Physiotherapy of the Affiliated Hospital of Medical College of Chinese Armed Police Forces. PARTICIPANTS： A total of 120 inpatients with cerebral infarction of different stages, including 75 males and 45 females, aged 41-75 years, were selected from November 2005 to December 2006 at the Department of Traditional Chinese Medicine Rehabilitation and Physiotherapy in Affiliated Hospital of Medical College of Chinese Armed Police Forces. Diagnostic criteria： in accordance with ＂main points of diagnosis on different cerebrovascular disease＂ secondly revised in the Second Cerebrovascular Disease Academic Meeting of Chinese Medicine Association in 1986. All accepted subjects provided confirmed consent, and the experiment received ethical permission from the hospital＇s ethics committee. METHODS： ① Experiment grouping： All inpatients were divided into four groups with non-stochastic concurrent control method according to the disease course： Group Ⅰ （onset within 7 hours）, group Ⅱ （onset from 7 hours to 3 days）, group Ⅲ （onset within 4-7 days）, and group IV （onset within 21-180 days）. On the basis of symptomatic treatment with western medicine, each group received Xingnao Kaiqiao therapy after onset within 7 hours, 7 hours to 3 days, 4 to 7days, and 21 to 180 days. ① The principal acupoints were Neiguan, Renzhong, and Sanyinfiao. ② The auxiliary acupoints were Jiquan, Chize, and Weizhong. ③Acupuncture manipulations： initially, Neiguan （PC6, bilateral） was needled

关键词： cerebral infarction Xingnao Kaiqiao acupuncture acupuncture therapy clinical effects intervention time