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多重扰动清种式大蒜单粒取种排种器设计与试验

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农业机械学报 2024年第1期55卷 65-75,163页

作者：侯加林方立志张海阔周凯李天华李玉华山东农业大学机械与电子工程学院泰安271018 山东省农业装备智能化工程实验室泰安271018

针对勺链式大蒜播种机取种过程中常出现的漏种、重种问题,设计了一种多重扰动清种式大蒜单粒取种排种器。取种勺在充种阶段获取多粒蒜种,经多重扰动清种,最终取种勺内仅余1粒蒜种。本文以金乡蒜种为研究对象,阐述了排种器的工作原理,确... 详细信息

针对勺链式大蒜播种机取种过程中常出现的漏种、重种问题,设计了一种多重扰动清种式大蒜单粒取种排种器。取种勺在充种阶段获取多粒蒜种,经多重扰动清种,最终取种勺内仅余1粒蒜种。本文以金乡蒜种为研究对象,阐述了排种器的工作原理,确定了排种器的各项参数和多重扰动装置的最佳安装位置。通过DEM-MBD耦合仿真试验,分析了倾斜角、取种勺线速度对充种成功率的影响,以及凹槽形状对单粒取种率的影响。运用Box-Behnken中心组合试验方法,以第2弧形突出部分坡度、倾斜角、取种勺线速度为试验因素,以单粒取种率和漏种率作为评价指标,开展了三因素三水平正交试验。利用Design-Expert 8.0.6数据分析软件,分析了各因素对单粒取种率与漏种率的影响,对试验因素进行优化,确定了多重扰动装置最佳结构参数。设计试验台对仿真结果进行验证,倾斜角、取种勺线速度分别为15°、0.07 m/s的条件下,通过调节多重扰动装置与取种勺凹槽顶端距离适配不同级别蒜种,当Ⅰ级、Ⅱ级、Ⅲ级蒜种距离分别为0、6.1、12.1 mm时,单粒取种成功率分别为92.2%、97.2%、95.6%,具有良好的取种性能。

关键词：大蒜播种机多重扰动单粒取种排种器 DEM-MBD

GEOMETRICAL OPTICS IN AN INHOMOGENEOUS UNIVERSE

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Chinese Physics Letters 1989年第5期6卷 233-236页

作者： fang lizhi WU Xiangping Beijing Astronomical Observatory Academia SinicaBeijing

In comparison with a homogeneous universe,a clumpy universe possess two types of effects on geometrical optics:*** convergence due to the gravititational-lens effects of the clumps;*** divergence due to the less mass density outside the *** the other hand,thermodynamics requires that the total effects are double *** give us an effective method to judge the rationality of various calculations of the lensing effect in a clumpy universe.

关键词： universe divergence thermodynamics

NEUTRINO MASS AND SUPERNOVA 1987A

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Chinese Physics Letters 1987年第9期4卷 424-426页

作者： fang lizhi Beijing Astronomical Observatory Academia SinicaBeijing

If the rest mass of electron neutrinos is non-zero,the arrival times of neutrinos emitted from supernova 1987a will be dispersed due to the dependence of neutrino speed on their *** using this effect,an upper limit of the neutrino mass,5-10eV/c^(2),can be derived from the data of neutrinos recorded by Mont Blanc neutrino observatory.

关键词： energy dispersed limit

THE MAXIMUM LENGTH SCALE OF OBJECTS WTTH RFGULAR CONFIGURATION IN THE UNIVERSE

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Chinese Physics Letters 1988年第8期5卷 365-368页

作者： fang lizhi YAN Lin Beijing Asytronomical Observatory Academia SinicaBeijing Centre for Astrophysics University of Science and Technology of ChinaHefei

The maximum length scale of objects with regular configuration,which is the configuration of virialized objects,has been discussed in cosmic string *** was shown that this maximum scale is about the same as that of clusters of *** result can be used to explain why the objects with scale Less than clusters of galaxies often possess symmetrical configuration,while larger objects are always irregular.

关键词： galaxies theory cosmic

Path-tracking control based on a dynamic trigonometric function

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Information Processing in Agriculture 2019年第1期6卷 1-10页

作者： Yunyi Wang Shuo Zhang Zhongxiang Zhu Zhen Li Yuefeng Du lizhi fang Laboratory of Optimized Design for Modern Agricultural Equipment College of EngineeringChina Agricultural UniversityBeijing 100083China Huangshi Polytechnic College HubeiHuangshi 435003China

With the rapid development of the modern vehicle industry,the automated control of new vehicles is in increasing ***,traditional course control has been unable to meet the actual needs of such *** solve this problem,more precise pathtracking control technologies have attracted increased *** paper presents a new algorithm based on the latitude and longitude information,as well as a dynamic trigonometric function,to improve the accuracy of position ***,the algorithm takes the course deviation and adjustment time as the optimization objectives and the given path and speed as the *** controller continuously adjusts the output through a cyclic“adjustment and detection”***,through an integration of the steering,positioning,and speed control systems,an experimental platform of a path-tracking control system based on the National Instruments(NI)myRIO controller and LabVIEW was *** addition,path-tracking experiments were carried out along a linear path,while changing lanes,and on a curved *** comparing and analyzing the experimental results,it can be seen that the average deviation in lateral displacement along the linear and curved paths was 0.32 and0.8 cm,and the standard deviation of the lateral displacement was 2.65 and 2.39 cm,*** changing lanes,the total adjustment time for the vehicle close to the target line to reach stability was about 1.5 ***,the experimental results indicate that the new algorithm achieves good stability and high control accuracy,and can overcome directional and positional errors caused by road interference while driving,meeting the precision requirements of automated vehicle control.

关键词： Path-tracking control Trigonometric function NI myRIO controller LabVIEW

Investigation of the growth and optical properties of a Co^2＋-doped Na5Lu9F(32) single crystal

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Chinese Optics Letters 2018年第6期16卷 68-72页

作者： lizhi fang Jianxu Hu Haiping Xia Jianli Zhang Yongsheng Zhu Baojiu Chen Key Laboratory of Photo-Electronic Materials Ningbo University Ningbo 315211 China College of Physics and Electronic Engineering College of Chemistry and Pharmaceutical Engineering Nanyang Normal University Nanyang 473061 China Department of Physics Dalian Maritime University Dalian 116026 China

A 0.1 mol.% CoF2-doped Na5Lu9F（32）single crystal with high quality in the size of -φ10 mm×100 mm was grown by the Bridgman method. Three peaks located at 504, 544, and 688 nm and a broad band in the range of 1200–1600 nm centered at 1472 nm were observed in the absorption spectra. The absorption peak position suggests cobalt ions in the divalent state in the grown crystal. Moreover, the cobalt ions are confirmed to locate in the distorted cubic crystal structure. Upon excitation of 500 nm light, a sharp emission peak at 747 nm ascribed to the ^2T2（H1） →^4A2（F） transition was observed for the crystal. The Co^2＋-doped Na5Lu9F（32）crystal shows a potentially promising material for the application of a passively Q-switched laser operating in the near-infrared range.

关键词： Na doped Na5Lu9F single crystal

Luminescent characteristics of Tm^(3+)/Tb^(3+)/Eu^(3+) tri-doped Na_(5)Y_(9)F_(32) single crystals for white emission with high thermal stability

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Chinese Physics B 2022年第12期31卷 544-549页

作者： lizhi fang Xiong Zhou Zhiwei Zhao Biao Zheng Haiping Xia Jun Wang Hongwei Song Baojiu Chen Key Laboratory of Photo-electronic Materials Ningbo UniversityNingbo 315211China Taizhou Special Equipment Inspection and Research Institute Taizhou 318000China Fujian Provincial Key Laboratory of Functional Marine Sensing Materials Center for Advanced Marine Sensing Materials and Smart SensorsMinjiang UniversityFuzhou 350108China State Key Laboratory on Integrated Optoelectronics College of Electronic Science and Engineering and College of PhysicsJilin UniversityChangchun 130012China Department of Physics Dalian Maritime UniversityDalian 116026China

By using an improved Bridgman method,0.3 mol%Tm^(3+)/0.6 mol%Tb^(3+)/y mol%Eu^(3+)(y=0,0.4,0.6,0.8)doped Na_(5)Y_(9)F_(32)single crystals were *** x-ray diffraction,excitation spectra,emission spectra and fluorescence decay curves were used to explore the crystal structure and optical performance of the obtained *** excited by 362 nm light,the cool white emission was realized by Na_(5)Y_(9)F_(32)single crystal triply-doped with 0.3 mol%Tm^(3+)/0.6 mol%Tb^(3+)/0.8 mol%Eu^(3+),in which the Commission Internationale de l’Eclairage(CIE)chromaticity coordinate was(0.2995,0.3298)and the correlated color temperature(CCT)was 6586 *** integrated normalized emission intensity of the tridoped single crystal at 448 K could keep 62%of that at 298 *** internal quantum yield(QY)was calculated to be~15.16%by integrating *** results suggested that the single crystals tri-doped with Tm^(3+),Tb^(3+)and Eu^(3+)ions have a promising potential application for white light-emitting diodes(w-LEDs).

关键词： Tm^(3+)/Tb^(3+)/Eu^(3+)triply-doped Na_(5)Y_(9)F_(32) white light emission energy transfer process thermal stability

Photocatalytic oxidation of methane to methanol over zinc titanate supported silver catalysts

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Journal of Rare Earths 2024年第5期42卷 899-906,I0004页

作者： Yuyan Gan Jinbi Huang Qian Lv Yanru Li lizhi Wu YU Tang Yuanxing fang Pengfei Zhu Li Tan Institute of Molecule Catalysis and In-Situ/Operando Studies State Key Laboratory of Photocatalysis on Energy and EnvironmentCollege of ChemistryFuzhou UniversityFuzhou350108China School of Environmental Science and Engineering Shaanxi University of Science and TechnologyXi'an 70021China

The direct activation of methane under mild condition to achieve highly selective of oxygenates is a challenging *** this study,a well dispersed silver supported ZnTiO_(3) catalyst was prepared to achieve selective preparation of methanol from methane and water under mild condition.X-ray diffraction,transmission electron microscopy and X-ray photoelectron spectroscopy characterizations demonstrate that silver species are uniformly dispersed on ZnTiO_(3) surface in the form of metallic silver *** photoelectric characterizations reveal that the addition of silver species enhances light absorption and promotes charge separation of the *** the reaction conditions of 50℃and 3 MPa,the methanol is obtained as the only liquid product over the designed Ag/ZnTiO_(3) catalyst under light *** this photocatalytic process,the holes generated by ZnTiO_(3) activate water to produce intermediate·OH,which further reacts with methane to synthesize *** silver species as co-catalysts extend the light absorption range of ZnTiO_(3) as well as promote charge separation.

关键词： Photocatalytic Methane oxidation Zinc titanate Silver Methanol

Realizing methanol synthesis from CO and water via the synergistic effect of Cu^(0)/Cu^(+)over Cu/ZrO_(2) catalyst

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Journal of Energy Chemistry 2024年第6期93卷 126-134,I0004页

作者： Yuan fang Fan Wang Yang Chen Qian Lv Kun Jiang Hua Yang Huibo Zhao Peng Wang Yuyan Gan lizhi Wu Yu Tang Xinhua Gao Li Tan Institute of Molecular Catalysis and In Situ/Operando Studies Fujian Key Laboratory of Electrochemical Energy Storage MaterialsState Key Laboratory of Photocatalysis on Energy and EnvironmentCollege of ChemistryFuzhou UniversityFuzhou 350108FujianChina Leibniz-Institut für Katalyse e.V.an der Universität Rostock Albert-Einstein Strasse 9118059 RostockGermany Department of Chemistry Tsinghua UniversityBeijing 100084China State Key Laboratory of High-Efficiency Utilization of Coal and Green Chemical Engineering College of Chemistry and Chemical EngineeringNingxia UniversityYinchuan 750021Ningxi1China

The optimizing utilization of ca rbon resources has drawn wide attention all over the world,while exploiting the high-efficiency catalytic routes remains a ***,a direct methanol synthesis route is realized from pure CO and H_(2)O over 10%Cu/t-ZrO_(2) catalyst,where the time yield of methanol is144.43 mmol mol_(Cu)^(-1)h^(-1)and the methanol selectivity in hydrocarbons is 100%,The Cu species highly dispersed in the t-ZrO_(2) support lead parts of them in the cationic *** Cu^(+)sites contribute to the dissociation of H_(2)O,providing the H*source for methanol synthesis,while the formed Cu^(0) sites promote the absorption and transfer of H*during the ***,the H_(2)O is even a better H resource than H_(2) due to its better dissociation effectivity in this catalytic *** present work offers a new approach for methanol synthesis from CO and new insight into the process of supplying H donor.

关键词： H_(2)O CO Methanol Cu-based catalysts t-ZrO_(2)