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Multi-frequency focusing of microjets generated by polygonal prisms

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Chinese Physics B 2022年第3期31卷 248-258页

作者： Yu-Jing yang De-Long Zhang ping-Rang hua School of Precision Instruments and Opto-electronics Engineering and Key Laboratory of Optoelectronic Information Science&Technology(Ministry of Education)Tianjin UniversityTianjin 300072China

We systematically investigate the power distribution characteristics of microjets generated by prismatic scatterers with different shapes at sub-THz region(λ = 8.57 mm). Among these prismatic scatterers, the hexagonal-type one shows better focusing feature than the others. Aiming at the hexagonal-type one, we propose a double-layer scatterer composed of a Teflon hexagonal prism as an outer layer and a semiconductor cuboid as an inner layer. Aiming at the double-layer scatterer, we further study the effects of refractive index, size, and shape of the inner cuboid on microjet’s features. The study allows us to present an optimized double-layer scatterer, which has a side length λ/2(λ) and a refractive index 2.0(1.4) for the inner(outer) layer. We show that the optimized scatterer can produce an ultra-strong, ultra-narrow microjet with a power enhancement of;0 and a full width at half maximum(FWHM) of;0.26λ, and the microjet is just located at the output face. The microjet keeps compact within the distance range of λ from the output face. These features and effects are explained from the viewpoint of ray optics theory. According to the optimized double-layer scatterer, we further study the multi-frequency focusing features of the microjets, and find that the microjet remains good features at harmonic frequencies 2f_(0) and 3f_(0). In addition, we investigate the effect of an Au sphere presence in the center of the microjet on the power distribution. The results show that a spherical dark spot with a size similar to that of the Au sphere emerges in the area where the Au sphere is placed. The feature can be used to measure the size of a metallic particle.

关键词： photonic microjet hexagonal prism harmonical frequencies localized surface plasmon resonance

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广州地区几种市售淫羊藿药材的质量分析

时珍国医国药 2005年第11期16卷 1075-1076页

作者：王治平樊化杨珂罗勇张美英王一飞广州暨南大学药学院暨南生物医药研究开发基地广东广州510623

目的:对广州地区市场上流通的不同产地来源的淫羊藿药材所含淫羊藿苷和总黄酮的含量进行比较。方法:采用《中国药典》2000年版一部淫羊藿药材含量测定项下的方法测定淫羊藿约材所含淫羊藿苷和总黄酮的含量。结果:不同产地淫羊藿中淫羊... 详细信息

目的:对广州地区市场上流通的不同产地来源的淫羊藿药材所含淫羊藿苷和总黄酮的含量进行比较。方法:采用《中国药典》2000年版一部淫羊藿药材含量测定项下的方法测定淫羊藿约材所含淫羊藿苷和总黄酮的含量。结果:不同产地淫羊藿中淫羊藿苷和总黄酮的含量存在差异。结论:无论在理论上还是在实际应用上都具有—定的指导意义。

关键词：淫羊藿淫羊藿苷高效液相色谱法紫外分光光度法

Microstructure of a Ni Matrix Composite Coating Reinforced by In-situ TiC Particles Using Plasma Cladding

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材料热处理学报 2004年第05B期25卷 1041-1044页

作者： WUYu-ping WANGZe-hua LINping-hua DepartmentofMaterialSciencesandEngineering HohaiUniversityNanjingChina DepartmentofMaterialSciencesandEngineering HohaiUniversityNanjingChina／／DepartmentofMaterialSciencesandEngineeringSoutheastUniversityNanjingChina

Plasma cladding process was used to prepare the TiC/Ni composite coating on the mild steel substrates. The TiC particles were synthesized in-situ. Microstructure and properties of the coating were investigated by optical microscopy, X-Ray diffraction, SEM, TEM and microhardness tester. The results show that the interface between the coating and the substrate is metallurgically bonded. The coating was uniform and almost defect-free when [Ti+C] varied from 10% to 20% after ball milling. The microstructure of the coating is mainly composed of -Ni dendrite, interdendritic eutectic ( -Ni austenite, M23C6 and CrB) and TiC particles. Most of the TiC particles are spherical and a small fraction is blocky in size of l^2(im. The TiC particles are smaller at the bottom than near the top of the coating. The coating has a gradient microstructure and a highest hardness of lOOOHyO. 1.

关键词：显微结构等离子包覆复合涂层 TiC颗粒

Soil Insect Diversity and Abundance Following Different Fertilizer Treatments on the Loess Plateau of China

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Journal of Integrative Agriculture 2013年第9期12卷 1644-1651页

作者： LIN Ying-hua LU ping yang Xue-yun ZHANG Fu-dao Institute of Wetland Research Chinese Academy of Forestry Key Laboratory of Forest Protection of State Forestry Administration Research Institute of Ecology Environment and ProtectionChinese Academy of Forestry College of Resources and Environmental Sciences Northwest A&F University Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences

The presence of abundant and diverse communities of macro-arthropods is considered an indicator of sustainability in agroecosystems. This study was designed to investigate the effects of different fertilizer treatments on abundance and diversity of insects of arable loess soil on the Loess Plateau of China. These regimes included a control with no fertilizer addition or manure, treatments with application of mineral fertilizers （N, NK, NP, PK, NPK）, treatments with NPK in combination with organic materials such as wheat straw or maize stalk, treatments with two rates of organic manure application; and different crop rotations （Rot. 1： winter wheat summer maize; Rot.2： winter wheat summer maize soybean intercropping; and Rot.3： winter wheat or rapeseed summer maize soybean intercropping）. Soil macro-arthropods were collected from the plough layer （0-20 cm） and sorted by hand after each harvest in June and October 2001 and 2002. A total of 3 132 individuals were collected, from 7 orders and 55 families, dominated by Formicidae （61.72%） and Staphylinidae （14.24%）. The results showed that individuals and groups were significantly influenced by sampling dates, while groups were significantly influenced by the fertilization treatments. Soil insect biodiversity, as determined by the Shannon index, was significantly influenced by fertilization and sampling dates. The abundance of soil insects was positively and significantly correlated with soil moisture content in October 2002. Nitrogen, phosphorus and potassium fertilizers and incorporation of organic materials were favorable factors for abundance and diversity in arable loess soil.

关键词： long-term fertilization soil moisture soil insect loess soil

Controlled Entanglement Swapping for Continuous Variables

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Communications in Theoretical Physics 2008年第4期49卷 877-880页

作者： WU Dao-hua DONG ping yang Ming CAO Zhuo-Liang Key Laboratory of Opto-electronic Information Acquisition and Manipulation Ministry of Education School of Physics and Material Science Anhui University Hefei 230039 China The School of Science Hangzhou Dianzi University Hangzhou 310018 China

We propose a scheme for controlled entanglement swapping of continuous variable, where an EPR pair shared by two parties （Alice and Debbie） and a GHZ entangled state shared by three parties （Alice, Bob and Claire） are required. One optical beams of the EPR state will be entangled with the output mode displaced by Bob with the help of Claire. It is shown that the entanglement swapping can occur controlled by the third party （Claire）

关键词： entanglement swapping continuous variable EPR pair GHZ entangled state

MIMO-OFDM detection based on Monte Carlo probabilistic data association

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The Journal of China Universities of Posts and Telecommunications 2007年第3期14卷 5-9页

作者： yang Bin GONG ping LI Yong-hua WU Wei-ling Information Theory and Technology Education and Research Center Beijing University of Posts and Telecommunications Beijing 100876 China

This article proposes a spatial multiplexing and diversity joint transmit structure for multiple input multiple output（MIMO） - orthogonal frequency division multiplexing （OFDM） system. The structure uses space-frequency block coding （SFBC） over all its spatial multiplexing layers to obtain both space diversity and frequency diversity gain. The article derives a monte carlo probabilistic data association （PDA） detector to obtain a better bit error rate （BER） performance when compared to the generic PDA detector. Computer simulation results show that the proposed detector can reduce the inter-symbol interference（ISI） greatly, improve the system performance significantly, and lower the computation complexity to a proper lever.

关键词： MIMO OFDM Monte Carlo PDA

Characteristics of Heat Flux Through Slag Film of Mold Slag Used for High Al-TRIP Steel Casting

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Journal of Iron and Steel Research International 2010年第5期17卷 11-16页

作者： YU Xiong WEN Guang-hua TANG ping yang Bo School of Materials Science and Engineering Chongqing University Chongqing 400044 China

Due to the high content of the Al-TRIP steel, Al reacts with SiO2 in the mold slag during the casting process, which results in the increase of ωAl2O3 /ωSiO2 ratio and the Al2O3 content, respectively; the characteristic of heat transfer through the slag film is then changed, which influences the smooth operation of the continuous casting process. The heat flux simulator of mold slag film was used to study the change tendency of the heat flux density through slag film and the results were discussed; at the same time, the characteristics of the crystals in the No. 15 mold slag were determined by BSE and XRD. The results obtained show that heat flux density decreases with the increase of ωAl2O3 /ωSiO2 ratio. Heat flux density increases with the increase of Li2O and/or B2O3 content in the mold slag which contains 30 % of Al2 O3. Compared with the heat flux density of common slag of peritectic steel, a suitable mold slag containing 4% of B2O3 and 4% of Li2O is designed. The heat flux density is 0. 645 MW/m^2 when ωAl2O3 /ωSiO2 = 1. 46. Under this experimental condition, the CaF2 crystals precipitate in the mold slag used for Al-TRIP steel.

关键词： TRIP steel heat flux density ωAl2O3 /ωSiO2 ratio Li2O B2O3

A Class of Parameter-free Filled Functions for Box-constrained System of Nonlinear Equations

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Acta Mathematicae Applicatae Sinica 2016年第2期32卷 355-364页

作者： Liu-yang YUAN Zhong-ping WAN Qiu-hua TANG Yue ZHENG Hubei Province Key Laboratory of Systems Science in Metallurgical Process Wuhan University of Science and Technology School of Mathematics and Statistics Wuhan University Industrial Engineering Department Wuhan University of Science and Technology School of Management Huaibei Normal University

In this paper, a class of parameter-free filled functions is proposed for solving box-constrained system of nonlinear equations. Firstly, the original problem is converted into an equivalent global optimization problem. Subsequently, a class of parameter-free filled functions is proposed for solving the problem. Some properties of the new class of filled functions are studied and discussed. Finally, an algorithm which neither computes nor explicitly approximates gradients during minimizing the filled functions is presented. The global convergence of the algorithm is also established. The implementation of the algorithm on several test problems is reported with satisfactory numerical results.

关键词： system of nonlinear equations global optimization filled function method local minimizer globalminimizer

A novel 2.2 Gbps LVDS driver circuit design based on 0.35μm CMOS

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Journal of Semiconductors 2010年第10期31卷 110-114页

作者： Cai hua Li ping School of Microelectronics and Solid-State Electronics University of Electronic Science and Technology of China

This paper presents a novel high-speed low voltage differential signaling （LVDS） driver design for pointto-point communication. The switching noise of the driver was greatly suppressed by adding a charge/discharge circuit and the operating frequency of the circuit was also increased. A simple and effective common-mode feedback circuit was added to stabilize the output common-mode voltage. The proposed driver was implemented in a standard 0.35 μm CMOS process with a die area of 0.15 mm^2. The test result shows that the proposed driver works well at 2.2 Gbps with power consumption of only 23 mW and 21.35 ps peak-to-peak jitter under a 1.8 V power supply.

关键词： high-speed LVDS charge injection common-mode feedback