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基于响应面分析下中草药移栽机的优化设计

农机化研究 2025年第1期47卷 135-141页

作者：赵厚睿刘臻湖北中医药大学武汉430065 湖北轻工职业技术学院武汉430070

通过响应面分析法对中草药移栽机进行优化设计,以提高中草药种植效率和质量。首先,选取移栽速度、移栽深度和移栽器械倾角3个因素作为设计变量,选取移栽成功率和移栽损伤率作为评价指标;在此基础上,设计了一个采用多种传感器组合的控制... 详细信息

通过响应面分析法对中草药移栽机进行优化设计,以提高中草药种植效率和质量。首先,选取移栽速度、移栽深度和移栽器械倾角3个因素作为设计变量,选取移栽成功率和移栽损伤率作为评价指标;在此基础上,设计了一个采用多种传感器组合的控制系统,采用模糊控制算法进行控制,并通过试验得到的数据进行响应面分析,得出了最优设计方案。研究结果表明:最优移栽速度为0.2 m/s,最优移栽深度为15 cm,最优移栽器械倾角为25°;通过优化设计,中草药移栽机的移栽成功率提高了11.8%,移栽损伤率降低了9.6%,取得了较好的效果。

关键词：移裁机响应面分析参数优化多传感器中草药

First-principles Calculation Assisted Thermodynamic Modeling of Ti-Co-Cu Ternary System

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journal of Materials Science & Technology 2010年第4期26卷 317-326页

作者： Y.j. Yang X.M. Tao w.j. Zhu Z.H. Long H.S. liu Z.P. jin School of Materials Science and Engineering Central South University Changsha 410083 China Key Lab of Non-ferrous Metal Science and Engineering Ministry of Education Changsha 410081 China

Thermodynamic assessment of Ti-Co-Cu ternary system has been carried out by combining first-principle calculation and CALPHAD method. Firstly, formation enthalpies of stable and hypothesized compounds were calculated by first-principles method. Then, based on reported experimental information, a thermodynamic description of the Ti-Co-Cu ternary system was performed. Solution phases were treated as substitutional solutions of which excess Gibbs energies were formulated by Redlich-Kister polynomial, and the intermediate phases were described with sublattice models. All measured isothermal sections were reasonably reproduced. In addition, liquidus projection of this ternary system was further calculated, which may be useful for relevant materials processing.

关键词： First-principle CALPHAD Thermodynamic modeling

Harmonic balance-based approach for optimal time delay to control unstable periodic orbits of chaotic systems

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Acta Mechanica Sinica 2020年第4期36卷 918-925页

作者： Y.M.Chen Q.X.liu j.K.liu Department of Mechanics Sun Yat-sen UniversityGuangzhou 510275China

As a classical technique for chaos suppression,the time-delayed feedback controlling strategy has been widely developed by stabilizing unstable periodic orbits(UPOs)embedded in chaotic systems.A critical issue for achieving high controlling precision is to search for an appropriate time *** paper proposes a simple yet effective approach,based on incremental harmonic balance method,to determine the optimal time delay in the delayed feedback *** time delay is adjusted within the iterative scheme provided by the proposed method,and finally converges to the period of the target *** long as the optimal time delay is fixed,moreover,the attained solution makes it quite convenient to analyze its stability according to the Floquet theory,which further provides the effective interval of the feedback gain.

关键词： Chaos control Unstable periodic orbit Delayed feedback Optimal time delay Incremental harmonic balance method

Organic Light Emitting Diodes with Lithium Contained Alq3 as Electron Injection Layer

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Chemical Research in Chinese Universities 2002年第2期18卷 121-123页

作者： Zugang liu j.L.Pinto Department of Materials University of OxfordParks RoadOxford OX13PFUK Departamento de Física Universidade de Aveiro3810194 AveiroPortuga

lNovel lithium doped tris 8 hydroxylquinoline aluminium(Alq3:Li) layer is deposited between emission layer and electron injection aluminium electrode as an electron injection assistant layer in different organic light emitting diodes(OLED) to lower the electron injection barrier. In these devices, Alq3 is used as emission layer, and a bilayer film of N,N bis (1 naphhyl) N,N diphenyl 1,1 biphenyle 4,4' diamine(NPB) and 4,4,4' tris(3 methyl phenylphenylamino) triphenylamine( m MTDATA) used as hole transport layer(HTL). The electroluminescent performance of devices with different thicknesses of Alq3∶Li shows that the insertion of the lithium doped Alq3 layer can reduce the turn on voltage by at least 2 volts, and the stability of devices with this lithium doped Alq3 layer is improved too. It can also change the efficiency of devices. Compared with an ultra thin lithium fluoride(LiF) layer, Alq3∶Li sheet gives similar effects but higher efficiency and can be much thicker and hence it is easier to control the deposition.

关键词： Organic light emitting diodes Lithium layer Alq3 EI

Preparation of Ga_2O_3 thin film solar-blind photodetectors based on mixed-phase structure by pulsed laser deposition

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Chinese Physics B 2019年第1期28卷 171-177页

作者： Y M Lu C Li X H Chen S Han P j Cao F jia Y X Zeng X K liu w Y Xu w j liu D L Zhu College of Materials Science and Engineering Shenzhen Key Laboratory of Special Functional MaterialsShenzhen Engineering Laboratory for Advanced Technology of CeramicsGuangdong Research Center for Interfacial Engineering of Functional MaterialsShenzhen UniversityShenzhen 518060China

Gallium oxide(Ga_2O_3) thin films were deposited on a-Al2O3(1120) substrates by pulsed laser deposition(PLD) with different oxygen pressures at 650?C. By reducing the oxygen pressure, mixed-phase Ga_2O_3 films with α and β phases can be obtained, and on the basis of this, mixed-phase Ga_2O_3 thin film solar-blind photodetectors(SBPDs) were *** the responsivities of the mixed-phase Ga_2O_3 SBPDs and the single β-Ga_2O_3 SBPDs at a bias voltage of 25 V,it is found that the former has a maximum responsivity of approximately 12 A/w, which is approximately two orders of magnitude larger than that of the latter. This result shows that the mixed-phase structure of Ga_2O_3 thin films can be used to prepare high-responsivity SBPDs. Moreover, the cause of this phenomenon was investigated, which will provide a feasible way to improve the responsivity of Ga_2O_3 thin film SBPDs.

关键词： Ga2O3 mixed-phase solar-blind photodetector pulsed laser deposition

Effect of Base Material on Microstructure and Texture Evolution of a Ti–6Al–4V Electron-Beam welded joint

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Acta Metallurgica Sinica(English Letters) 2017年第5期30卷 499-504页

作者： G.Q.wang Z.B.Zhao B.B.Yu j.R.liu Q.j.wang j.H.Zhang R.Yang j.w.Li School of Materials Science and Engineering University of Science and Technology of China Institute of Metal Research Chinese Academy of Sciences Science and Technology on Power Beam Processes Laboratory Beijing Aeronautical Manufacturing Technology Research Institute

The effect of base material（BM） on microstructure and crystallographic orientation evolution of a Ti–6Al–4V electron-beam welded joint was investigated. Meanwhile, the crystallographic orientation of prior b grains was studied by advanced electron backscattered diffraction data processing. The inhomogeneity of microstructure within welded joint was formed due to the different microstructures of BM. By comparing microstructure details of the welded joint, including microstructure morphology and crystallographic orientation with those of the base material, it can be found that both the microstructure morphology and crystallographic orientation of the EBw joint would be controlled by BM.

关键词： Electron-beam welding Titanium alloys Prior b orientation Microstructure Texture

Isothermal study of effusion cooling flows using a large eddy simulation approach

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航空动力学报 2009年第4期24卷 729-739页

作者： w.P.Bennett j.j.Mc Guirk Aeronautical and Automotive Engineering Department Loughborough University

An isothermal numerical study of effusion cooling flow is conducted using a large eddy simulation(LES) *** main types of cooling are considered,namely tangential film cooling and oblique patch effusion *** represent tangential film cooling,a simplified model of a plane turbulent wall jet along a flat plate in quiescent surrounding fluid is *** contrast to a classic turbulent boundary layer flow,the plane turbulent wall jet possesses an outer free shear flow region,an inner near wall region and an interaction region,characterised by substantial levels of turbulent shear stress *** shear stress characteristics hold significant implications for RANS modelling,implications that also apply to more complex tangential film cooling flows with non-zero free stream *** LES technique used in the current study provides a satisfactory overall prediction of the plane turbulent wall jet flow,including the initial transition region,and the characteristic separation of the zero turbulent shear stress and zero shear strain *** effusion patch cooling is modelled using a staggered array of 12 rows of effusion holes,drilled at 30° to the flat plate *** effusion holes connect two channels separated by the flat ***,these comprise of a channel representing the combustion chamber flow and a cooling air supply channel.A difference in pressure between the two channels forces air from the cooling supply side,through the effusion holes,and into the combustion chamber *** from successive effusion rows coalesces to form an aerodynamic film between the combustion chamber main flow and the flat *** practical applications,this film is used to separate the hot combustion gases from the combustion chamber *** numerical model is shown to be capable of accurately predicting the injection,penetration,downstream decay,and coalescence of the effusion *** addition,the numerical model captures entrainmen

关键词： effusion cooling large eddy simulation isothermal analysis film cooling turbulent wall jet

Synchrotron micro-scale measurement of metal distributions in Phragmites australis and Typha latifolia root tissue from an urban brownfield site

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journal of Environmental Sciences 2016年第3期28卷 172-182页

作者： Huan Feng Yu Qian Frank j.Gallagher weiguo Zhang Lizhong Yu Changjun liu Keith w.jones Ryan Tappero Department of Earth and Environmental Studies Montclair State University Urban Forestry Program Department of EcologyEvolution and Natural ResourcesRutgersThe State University of New Jersey State Key Laboratory of Estuarine and Coastal Research East China Normal University Biological Environmental and Climate Sciences DepartmentBrookhaven National Laboratory Photon Sciences Directorate Brookhaven National Laboratory

Liberty State Park in New jersey,USA,is a ＂brownfield＂ site containing various levels of *** investigate metal uptake and distributions in plants on the brownfield site,Phragmites australis and Typha latifolia were collected in Liberty State Park during the growing season（May–September）in 2011 at two sites with the high and low metal loads,*** objective of this study was to understand the metal（Fe,Mn,Cu,Pb and Zn）concentration and spatial distributions in *** and *** root systems with micro-meter scale resolution using synchrotron X-ray microfluorescence（μXRF）and synchrotron X-ray computed microtomography（μCMT）*** root structure measurement by synchrotron μCMT showed that high X-ray attenuation substance appeared in the *** μXRF measurement showed that metal concentrations and distributions in the root cross-section between epidermis and vascular tissue were statistically *** correlations were found between metals（Cu,Mn,Pb and Zn）and Fe in the epidermis,implying that metals were scavenged by Fe *** results from this study suggest that the expression of metal transport and accumulation within the root systems may be element *** information derived from this study can improve our current knowledge of the wetland plant ecological function in brownfield remediation.

关键词： Phragmites australis Typha latifolia Trace metals Synchrotron radiation technique Brownfield

Interfacial stress engineering toward enhancement of ferroelectricity in Al doped HfO_(2) thin films

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Chinese Physics B 2024年第9期33卷 637-643页

作者： S X Chen M M Chen Y liu D w Cao G j Chen Department of Microelectronics Jiangsu UniversityZhenjiang 212013China Department of Physics Jiangsu UniversityZhenjiang 212013China Guangdong–Hong Kong–Macao joint Laboratory for Intelligent Micro-Nano Optoelectronic Technology Foshan UniversityFoshan 528225China

Ferroelectric HfO_(2)has attracted much attention owing to its superior ferroelectricity at an ultra-thin thickness and good compatibility with Si-based complementary metal-oxide-semiconductor(CMOS)***,the crystallization of polar orthorhombic phase(o-phase)HfO_(2)is less competitive,which greatly limits the ferroelectricity of the as-obtained ferroelectric HfO_(2)thin ***,the crystallization of o-phase HfO_(2)can be thermodynamically modulated via interfacial stress *** this paper,the growth of improved ferroelectric Al doped HfO_(2)(HfO_(2):Al)thin films on(111)-oriented Si substrate has been *** analysis has suggested that nonpolar monoclinic HfO_(2):Al grown on(111)-oriented Si substrate suffered from a strong compressive strain,which promoted the crystallization of(111)-oriented o-phase HfO_(2)in the as-grown HfO_(2):Al thin *** addition,the in-plane lattice of(111)-oriented Si substrate matches well with that of(111)-oriented o-phase HfO_(2),which further thermally stabilizes the o-phase HfO_(2).Accordingly,an improved ferroelectricity with a remnant polarization(2P_(r))of 26.7C/cm^(2) has been *** results shown in this work provide a simple way toward the preparation of improved ferroelectric HfO_(2)thin films.

关键词： improved ferroelectricity interfacial stress engineering compressive strain HfO_(2)