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Chinese Journal of Structural Chemistry 2006年第10期25卷 1197-1202页

作者： yu yun LIN Li-Rong HUANG Rong-Bin Department of Chemistry Longyan College Longyan Fujian 364000 China Department of Chemistry Xiamen University Xiamen 361005 China

The title compound, 1-4-（dimethylamino）benzylidene）-4-（naphthalene-1-yl） thiosemicarbazide （DMABNTS, C20H20N4S, Mr = 348.47）, was synthesized and characterized by elemental analysis, 1R, ^1H NMR and MS. The crystal structure of DMABNTS with 1,4-dioxane （Diox, C4H8O2） solvent molecules （DMABNTS·2Diox, C28H36N4O4S, Mr = 524.67） was determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic system, space group P21/c with a = 14.418（4）, b = 7.1702（19）, c = 28.350（7）°A,β= 101.154（6）°, V= 2875.4（13） °A^3, Z= 4, Dc= 1.212 g/cm^3, F（000） = 1120 and μ= 0.151 mm^-1. A total of 6458 reflections were collected, of which 4671 were unique. The structure was solved by direct methods and refined to the final R = 0.0732 and wR = 0.2127 for 3921 observed reflections （I〉 2σ（I））. There exist intermolecular hydrogen bonds （N（2）-H（2B）…S（1A）and N（1）-H（1A）…O（4B）） in the structure. The study of fluorescent properties ＇shows that DMABNTS emits bright solid-state fluorescence in the visible region and exhibits blue photoluminescence.

关键词： 1-(4-(dimethylamino)benzylidene)-4-(naphthalen- 1-yl)thiosemicarbazide synthesis crystal structure fluorescence

Facile synthesis of Au embedded CuOx-CeO2 core/shell nanospheres as highly reactive and sinter-resistant catalysts for catalytic hydrogenation of p-nitrophenol

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Nano Research 2020年第8期13卷 2044-2055页

作者： Ke Wu Xin-yu Wang Ling-Ling Guo yue-Jiao Xu Liang Zhou Ze-yu Lyu Kang-yu Liu Rui Si Ya-Wen Zhang Ling-Dong Sun Chun-Hua Yan Beijing National Laboratory for Molecular Sciences State Key Laboratory of Rare Earth Materials Chemistry and ApplicationsPKU-HKU Joint Laboratory in Rare Earth Materials and Bioinorganic Chemistryand College of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China Shanghai Synchrotron Radiation Facility Shanghai Institute of Applied PhysicsChinese Academy of SciencesShanghai201204China College of Chemistry and Chemical Engineering Lanzhou UniversityLanzhou730000China

Exploring cost-effective catalysts with high catalytic performance and long-term stability has always been a general concern for environment protection and energy ***,Au nanoparticles(NPs)embedded CuOx-CeO2 core/shell nanospheres(Au@CuOx-CeO2 CSNs)have been successfully prepared through a versatile one-pot method at ambient *** spontaneous auto-redox reaction between HAuCl4 and Ce(OH)3 in aqueous solution triggered the self-assembly growth of micro-/nanostructural Au@CuOx-CeO2 ***,the CuOx clusters in Au@CuOx-CeO2 CSNs are capable of improving the anti-sintering ability of Au NPs and providing synergistic catalysis *** a result,the confined Au NPs exhibited extraordinary thermal stability even at a harsh thermal condition up to 700℃.In addition,before and after the severe calcination process,Au@CuOx-CeO2 CSNs can exhibit enhanced catalytic activity and excellent recyclability towards the hydrogenation of p-nitrophenol compared to previously reported *** synergistic catalysis path between Au/CuOx/CeO2 triphasic interfaces was revealed by density functional theory(DFT)*** CuOx clusters around the embedded Au NPs can provide moderate adsorption strength of p-nitrophenol,while the adjacent CeO2-supported Au NPs can facilitate the hydrogen dissociation to form H*species,which contributes to achieve the efficient reduction of *** study opens up new possibilities for developing high-efficient and sintering-resistant micro-/nanostructural nanocatalysts by exploiting multiphasic systems.

关键词： core/shell nanostructure sinter-resistant catalysts triphasic interfaces catalysis p-nitrophenol reduction

Loading direction-dependent shear behavior at different temperatures of single-layer chiral graphene sheets

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Acta Mechanica Sinica 2018年第3期34卷 542-548页

作者： Yang Zhao Shuhong Dong Peishi yu Junhua Zhao Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment and Technology Jiangnan University

The loading direction-dependent shear behavior of single-layer chiral graphene sheets at different temperatures is studied by molecular dynamics （MD） simulations. Our results show that the shear properties （such as shear stress-strain curves, buckling strains, and failure strains） of chiral graphene sheets strongly depend on the loading direction due to the structural asymmetry. The maximum values of both the critical buckling shear strain and the failure strain under positive shear deformation can be around 1.4 times higher than those under negative shear deformation. For a given chiral graphene sheet, both its failure strain and failure stress decrease with increasing temperature. In particular, the amplitude to wavelength ratio of wrinkles for different chiral graphene sheets under shear deformation using present MD simulations agrees well with that from the existing theory. These findings provide physical insights into the origins of the loading direction-dependent shear behavior of chiral graphene sheets and their potential applications in nanodevices.

关键词： Chiral grapheme Shear behavior Buckling strain Wrinkles

Ceramic coating electric-deposited by high-energy pulse

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Chinese Science Bulletin 1999年第24期44卷 2228-2232页

作者： Weiping yu Xiaoping Wang Beijing Univ Aeronaut & Astronaut Teaching Ctr Mat & Machinery Beijing 100083 Peoples R China

A novel method to prepare ceramic coatings has been developed by making use of plasma energy produced from the pulsed discharge between electric conductor and aqueous electrolyte. A ZrO2-8%Y2O3 coating was obtained by this method, which had excellent adhesion with substrate, smooth surface and good resistance to high temperature oxidation.

关键词： high-energy pulse electric-deposition ceramic coating.

Output Feedback for Stochastic Nonlinear Systems with Unmeasurable Inverse Dynamics

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International Journal of Automation and computing 2009年第4期6卷 391-394页

作者： Xin yu Na Duan School of Automation Southeast University Nanjing 210096 PRC Institute of Automation Qufu Normal University Qufu 273165 PRC School of Electrical Engineering ＆ Automation Xuzhou Normal University Xuzhou 221116 PRC

This paper considers a concrete stochastic nonlinear system with stochastic unmeasurable inverse dynamics. Motivated by the concept of integral input-to-state stability （iISS） in deterministic systems and stochastic input-to-state stability （SISS） in stochastic systems, a concept of stochastic integral input-to-state stability （SiISS） using Lyapunov functions is first introduced. A constructive strategy is proposed to design a dynamic output feedback control law, which drives the state to the origin almost surely while keeping all other closed-loop signals almost surely bounded. At last, a simulation is given to verify the effectiveness of the control law.

关键词： Output feedback stochastic input-to-state stability (SISS) stochastic integral input-to-state stability (SilSS) stochastic inverse dynamic stochastic nonlinear systems.

Static Properties of Λ-Hypernuclei

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Chinese Physics Letters 2001年第8期18卷 1030-1032页

作者： TAN yu-Hong LUO Yan-An NING Ping-Zhi MA Zhong-yu Department of Physics Nankai UniversityTianjin 300071 China Institute of Atomic Energy Beijing 102413

Static properties ofΛ-hypernuclei are calculated self-consistently in the relativistic mean-field *** effect ofΛon the core nucleons are *** is found that the rms radii of neutron become smaller than those of ordina... 详细信息

关键词： model ordinary relativistic

A Tracking Filter in Spherical Coordinates Enhanced by De-noising of Converted Doppler Measurements

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Chinese Journal of Aeronautics 2012年第5期25卷 757-765页

作者： ZHOU Gongjian yu Changjun CUI Naigang QUAN Taifan School of Electronics and Information Engineering Harbin Institute of Technology Harbin 150001 China School of Information and Electronic Engineering Harbin Institute of Technology at Weihai Weihai 264209 China School of Astronautics Harbin Institute of Technology Harbin 150001 China

Tracking problem in spherical coordinates with range rate （Doppler） measurements, which would have errors correlated to the range measurement errors, is investigated in this paper. The converted Doppler measurements, constructed by the product of the Doppler measurements and range measurements, are used to replace the original Doppler measurements. A de-noising method based on an unbiased Kalman filter （KF） is proposed to reduce the converted Doppler measurement errors before updating the target states for the constant velocity （CV） model. The states from the de-noising filter are then combined with the Cartesian states from the converted measurement Kalman filter （CMKF） to produce final state estimates. The nonlinearity of the de-noising filter states are handled by expanding them around the Cartesian states from the CMKF in a Taylor series up to the second order term. In the mean time, the correlation between the two filters caused by the common range measurements is handled by a mini- mum mean squared error （MMSE） estimation-based method. These result in a new tracking filter, CMDN-EKF2. Monte Carlo simulations demonstrate that the proposed tracking filter can provide efficient and robust performance with a modest computa- tional cost.

关键词： target tracking converted Doppler range rate nonlinear Kalman filtering

Submicron LaB_6 powders with high purity prepared in large scale by salt-assisted combustion synthesis

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Journal of Rare Earths 2018年第6期36卷 623-629页

作者： Zhengning Li yujing Ou Peiqing La yu Shi State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of Technology

LaB6 powders were synthesized in large scale by salt-assisted combustion synthesis(CS) with different NaCl diluent contents. The variety of phases, particle size and purity of the powders were investigated using X-ray diffraction(XRD), scanning electron microscopy(SEM), energy dispersive spectrometer(EDS), and transmission electron microscope(TEM). With increase of NaCl content, the adiabatic combustion temperature of the reaction system linearly declines, the average particle size of leached products decreases, the impurity phases are easier to remove, and the products purity enhances obviously. When NaCl content is 40 wt%, the purity of the superfine powders of LaBis more than 98 wt%, and the average particle size is 380 nm.

关键词： Combustion synthesis LaB_6 powders Purity Particle size Rare earths

Sphere decoder for polar codes concatenated with cyclic redundancy check

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Science China(Information Sciences) 2019年第8期62卷 159-171页

作者： Yongrun yu Zhiwen PAN Nan LIU Xiaosi TAN National Mobile Communications Research Laboratory Southeast University

The existing cyclic redundancy check(CRC)-aided successive cancellation list(CA-SCL) decoder partitions the decoding process into two steps, where an SCL is followed by a CRC check. An SCL decoder can approach the maximum-likelihood(ML) decoding performance of the inner polar codes using a sufficiently large list; however, in this case, CRC is only used for performing error detection. Therefore, the decoding performance of the outer CRC is different from that of ML because the errors are not rectified, which degrades the performance of the entire concatenated codes. In this study, we propose a sphere decoder(SD) that can achieve the ML performance of polar codes concatenated with CRC to address the suboptimality of CASCL decoding. The proposed SD performs joint decoding of the CRC-polar codes in a single step, thereby avoiding the polar decoding and CRC detection decoding scheme. Because the proposed SD guarantees the ML decoding performance of the CRC-polar concatenated codes, the simulation results demonstrate that the block error rate(BLER) of the proposed SD acts as the lower bound of the CA-SCL decoding performance. Further, a new initial radius selection method is proposed for the SD to reduce the average decoding complexity. The simulations demonstrate that the proposed initial radius selection method reduces more amount of decoding complexity when compared with that reduced using sequential step size methods.

关键词： polar codes sphere decoder maximum-likelihood decoding optimal decoding radius search

Effects of ferrous and manganese ions on anammox process in sequencing batch biofilm reactors

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Journal of Environmental Sciences 2014年第5期26卷 1034-1039页

作者： Xiaoli Huang Dawen Gao Sha Peng yu Tao State Key Laboratory of Urban Water Resource and Environment Harbin Institute of Technology School of Forestry Northeast Forestry University

Ferrous and manganese ions, as essential elements, significantly affect the synthesis of Haem-C, which participates in the energy metabolism and proliferation of anammox bacteria. In this study, two identical sequencing batch biofilm reactors were used to investigate the effects of ferrous and manganese ions on nitrogen removal efficiency and the potential of metal ions serving as electron donor/acceptors in the anammox process. Fluorescence in situ hybridization analysis was applied to investigate the microbial growth. Results showed that the nitrogen removal increased at high concentrations of Fe2＋ and Mn2＋ and the maximum removal efficiency was nearly 95% at Fe2＋ 0.08 mmol/L and Mn2＋ 0.05 mmol/L, which is nearly 15% and 8% higher than at the lowest Fe2＋ and Mn2＋ concentrations （0.04 and 0.0125 mmol/L）. The stabilities of the anammox reactor and the anammox bacterial growth were also enhanced with the elevated Fe2＋ and Mn2＋ concentrations. The Fe2＋ and Mn2＋were consumed by anammox bacteria along with the removal of ammonia and nitrite. Stoichiometry analysis showed Fe2＋ could serve as an electron donor for NO3-N in the anammox process. Nitrate could be reduced with Fe2＋ serving as the electron donor in the anammox system, which causes the value of NO^-N/NH4-N to decrease with the increasing of N-removal efficiency.

关键词： anaerobic ammonium oxidation (anammox) ferrous ion manganese ion nitrogen removal electron donor