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Path tracking control of autonomous agricultural mobile robots

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第10期8卷 1596-1603页

作者： ZHU Zhong-xiang CheN Jun YOSHIDA Toyofumi TORISU Ryo song Zheng-he MAO En-rong College of Engineering China Agricultural University Beijing 100083 China College of Mechanical and Electronic Engineering Northwest A＆F University Yangling 712100 China Faculty of Agriculture Iwate University Morioka 0208550 Japan

In a tractor automatic navigation system, path planning plays a significant role in improving operation efficiency. This study aims to create a suboptimal reference course for headland turning of a robot tractor and design a path-tracking controller to guide the robot tractor along the reference course. A time-minimum suboptimal control method was used to generate the reference turning course based on the mechanical parameters of the test tractor. A path-tracking controller consisting of both feedforward and feedback component elements was also proposed. The feedforward component was directly determined by the desired steering angle of the current navigation point on the reference course, whereas the feedback component was derived from the designed optimal controller. Computer simulation and field tests were performed to validate the path-tracking performance. Field test results indicated that the robot tractor followed the reference courses precisely on flat meadow, with average and standard lateral devia- tions being 0.031 m and 0.086 m, respectively. However, the tracking error increased while operating on sloping meadow due to the employed vehicle kinematic model.

关键词： headland turning Path creation Path-tracking controller Optimal control Robot tractor

pH-controlled DNAzymes： Rational design and their applications in DNA-machinery devices

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Nano Research 2016年第10期9卷 3084-3092页

作者： Yuqi Chen Yanyan song Zhiyong he Zijing Wang Wenting Liu FuanWang Xiaolian Zhang xiang Zhou College of Chemistry and Molecular Sciences The Institute for Advanced Studies Wuhan University Wuhan 430072 China School of Medicine Wuhan University Wuhan 430071 China

The availability and reliability of strategies for molecular biosensing over a finely adjustable dynamic range is essential to enhance the understanding and control of vital biological process. To expand the versatility and utility of nucleic acid- related enzymes, we demonstrated a rational approach to acquiring tunable, pH-dependent deoxyribozymes （DNAzymes） with catalytic activities and response sensitivities that can be tuned through a simple change in solution pH. To do this, we capitalized upon the pH dependence of Hoogsteen interactions and designed i-motif- and triplex-based DNAzymes that can be finely regulated with high precision over a physiologically relevant pH interval. The modified DNAzymes are dependent upon pH for efficient cleavage of substrates, and their catalytic performance can be tuned by regulating the sequence of inserted i-motif/triplex structures. The principle of tunable, pH-dependent DNAzymes provides the opportunity to engineer pH-controlled DNA-machinery devices with unprecedented sensitivity to pH changes. For example, we constructed a DNA-walker device, the stepping rate of which could be adjusted by simply modulating solution pH within an interval of 5.6 to 7.4, as well as a DNA tetrahedron that can be opened at pH 6.4 and kept closed at pH 7.4. The potential of this approach is not limited to serve as pH-dependent devices, but rather may be combined with other elements to expand their practical usefulness.

关键词： pH iMNAzyme TNAzyme DNA walker DNA tetrahedron

Effect of Calix[4]pyrrole as Addition Reagent on Anions Separation in Capillary Zone Electrophoresis (CZE)

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Chinese Chemical Letters 2001年第6期12卷 511-512页

作者： Li Jun he Qing song CAI Shi Jun SHAO Sheng xiang JIANG Lanzhou Institute of Chemical Physics Chinese Academy of sciencesLanzhou 730000

Supramolecular interaction of calix[4]pyrroles with several inorganic anions is reported by addition of calix[4]pyrroles to background electrolyte (BGE) in CZE. The retention time (t(R)) of all anions increased with i... 详细信息

关键词： Supramolecular interaction calixpyrroles CZE retention time.

Tuning Structure of Manganese Oxides to Achieve High-performance Aqueous Zn Batteries

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Chinese Journal of Structural Chemistry 2020年第3期39卷 388-394,375页

作者： ZHAO Qing-he DING Shou-xiang song Ao-Ye QIN Run-Zhi PAN Feng School of Advanced Materials Peking UniversityShenzhen Graduate SchoolShenzhen 518055China

As a key material for the development of mild aqueous rechargeable Zn/MnO2 cells, MnO2 has attracted much attention. This article presents some issues of MnO2, provides some strategies improving battery performance of MnO2 electrode, as well as makes a perspective on future research and development of MnO2 materials. This article offers a profound insight on structure/property relationship of MnO2, and benefits a lot to those involved in energy storage and conversion applications.

关键词： manganese oxides aqueous Zn battery phase structure charge storage mechanism electrochemistry

The eff ect of Rhizophagus irregularis on salt stress tolerance of Elaeagnus angustifolia roots

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Journal of Forestry Research 2020年第6期31卷 2063-2073页

作者： Wenyuan he Xiaoxu Fan Zixin Zhou Huanhuan Zhang xiang Gao Fuqiang song Gui Geng Engineering Research Center of Agricultural Microbiology Technology Ministry of EducationHeilongjiang UniversityHarbin 150080China heilongjiang Provincial Key Laboratory of Ecological Restoration and Resource Utilization for Cold Region School of Life SciencesHeilongjiang UniversityHarbin 150080China

We assessed the eff ects of arbuscular mycorrhizal fungi(AMF)Rhizophagus irregularis inoculation on salt stress tolerance in roots of the drought-tolerant plant Elaeagnus *** studied a plant growth index,spore density and hyphal length density of AMF,the Na+contents and ultrastructure of root cells,as well as rhizosphere soil enzyme activities of mycorrhizal and non-mycorrhizal *** seedlings under diff erent salt *** salt stress,growth of *** with mycorrhizal inoculation was higher than that of non-inoculated *** spore density and hyphal length density decreased signifi cantly under salt stress in rhizosphere soil of mycorrhizal *** seedlings(phe root cells of *** seedlings inoculated with *** at 300 mmol L−1 salt had more organelles,greater integrity,and lower root Na+contents than those of non-inoculated *** addition,the results showed notably higher activities of catalase,phosphatase,urease and saccharase in rhizosphere soil of the mycorrhizal seedlings in response to salinity compared to those of the non-mycorrhizal ***,AMF inoculation could enhance salt stress tolerance in roots of ***.

关键词： Salt stress Arbuscular mycorrhizal fungi Elaeagnus angustifolia Na+content Ultrastructure of root cell Soil enzyme

Improving corrosion resistance of Zn-5Al(wt%)alloy by microalloying with samarium

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Journal of Rare Earths 2023年第10期41卷 1636-1644,I0006页

作者： Xiaochao Zhou Wei Shi song xiang College of Materials and Metallurgy Guizhou UniversityGuiyang550025China Key Laboratory for Mechanical Behavior and Microstructure of Materials of Guizhou Province Guiyang550025China National&Local Joint Engineering Laboratory for High-Performance Metal Structure Material and Advanced Manufacturing Technology Guiyang550025China

The role of the rare earth element Sm in as-cast Zn-5AI alloy was studied in this work.A three times higher improvement than the control group on corrosion resistance was found with rare earth Sm adding(0.15 wt%).By using an electron prove micro analyzer(EPMA),focused ion beam(FIB)and scanning Kelvin probe force microscopy(SKPFM)techniques,two main mechanisms of the premium performance of the Sm adding were *** was that the non-uniform nucleation and component undercooling induced by Sm adding,reduced theα-AI layer spacing thus improved the covering efficiency of the Al_(2)O_(3)*** other was that the dissolved Sm in the Zn/Al eutectic structure modulated the electron work function thus induced the attenuation of Volta potential *** experimental results show that when the addition of Sm is 0.15 wt%,the minimum Volta potential difference betweenα-AI andη-Zn phases is achieved,and excessive or deficient Sm addition will increase the Volta potential difference.

关键词： Zn-5Al Sm Rare earth elements SKPFM Volta potential

Interdigital MnO_(2)/PEDOT Alternating Stacked Microelectrodes for High-Performance On-Chip Microsupercapacitor and Humidity Sensing

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Energy & Environmental Materials 2024年第2期7卷 257-267页

作者： Muhammad Tahir Lihong Li Liang he Zhongyuan xiang Zeyu Ma Waqas Ali Haider Xiaoqiao Liao Yanlin song Key Laboratory of Green Printing CAS Research/Education Centre for Excellence in Molecular SciencesInstitute of Chemistry Chinese Academy of Sciences(ICCAS)Beijing 100190China School of Mechanical Engineering Sichuan UniversityChengdu 610065China A.S.Chemical Laboratories Inc. Concord L4K 4M4ON Canada

For microelectronic devices,the on-chip microsupercapacitors with facile construction and high performance,are attracting researchers'prior consideration due to their high compatibility with modern ***,we proposed interchanging interdigital Au-/MnO_(2)/polyethylene dioxythiophene stacked microsupercapacitor based on a microfabrication process followed by successive electrochemical *** stacked configuration of two pseudocapacitive active microelectrodes meritoriously leads to an enhanced contact area between MnO_(2)and the conductive and electroactive layer of polyethylene dioxythiophene,hence providing excellent electron transport and diffusion pathways of electrolyte ions,resulting in increased pseudocapacitance of MnO_(2)and polyethylene *** stacked quasi-solid-state microsupercapacitors delivered the maximum specific capacitance of 43 mF cm^(-2)(211.9 F cm^(-3)),an energy density of 3.8μWh cm^(-2)(at a voltage window of 0.8 V)and 5.1μWh cm^(-2)(at a voltage window of 1.0 V)with excellent rate capability(96.6%at 2 mA cm^(-2))and cycling performance of 85.3%retention of initial capacitance after 10000 consecutive cycles at a current density of 5 mA cm^(-2),higher than those of ever reported polyethylene dioxythiophene and MnO_(2)-based planar *** from the favorable morphology,bilayer microsupercapacitor is utilized as a flexible humidity sensor with a response/relaxation time superior to those of some commercially available integrated *** strategy will be of significance in developing high-performance on-chip integrated microsupercapacitors/microsensors at low cost and environment-friendly routes.

关键词： electrochemical polymerization microsensor microsupercapacitor stacked microelectrode

补脾强力复方对EAMG大鼠血清CORT、E、ACTH、CRH干预作用的研究

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湖南中医杂志 2018年第3期34卷 164-166页

作者：陈薇王静况时祥何前松楚兰张艺凡贵阳中医学院贵州贵阳550002 湖北省武汉市新洲区中医院湖北武汉430400 贵阳中医学院第二附属医院贵州贵阳550003 贵州医科大学贵州贵阳550025

目的:观察补脾强力复方对实验性自身免疫性重症肌无力(EAMG)大鼠血清皮质醇(CORT)、肾上腺素(E)、促肾上腺皮质激素(ACTH)、促肾上腺皮质激素释放激素(CRH)的影响,探讨补脾强力复方治疗重症肌无力(MG)的可能机制。方法:采用鼠源性AchR-... 详细信息

目的:观察补脾强力复方对实验性自身免疫性重症肌无力(EAMG)大鼠血清皮质醇(CORT)、肾上腺素(E)、促肾上腺皮质激素(ACTH)、促肾上腺皮质激素释放激素(CRH)的影响,探讨补脾强力复方治疗重症肌无力(MG)的可能机制。方法:采用鼠源性AchR-α亚基97-116肽段序列(R97-116)免疫接种雌性Lewis大鼠,建立EAMG大鼠动物模型;通过ELISA法检测EAMG大鼠免疫后第7周CORT、E、ACTH、CRH含量水平,比较补脾强力复方大、中、小剂量与强的松的干预效果。结果:与正常组比较,模型组大鼠血清ACTH、CRH水平显著升高(P0.05);与模型组比较,补脾强力复方各剂量组及强的松组ACTH、CRH水平显著降低(P<0.01),血清E、CORT水平显著升高(P<0.01);补脾强力复方大剂量组血清ACTH、CRH、E水平更接近正常组水平。结论:补脾强力复方能调节EAMG大鼠血清CRH、ACTH、E、CORT的分泌,能有效降低EAMG大鼠血清ACTH、CRH水平及升高E、CORT水平,其大剂量组使各激素的分泌更接近正常组水平,这可能是补脾强力复方治疗MG的可能机制。

关键词：重症肌无力补脾强力复方大鼠实验研究

Natural nematicidal active compounds:Recent research progress and outlook

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Journal of Integrative Agriculture 2021年第8期20卷 2015-2031页

作者： CheN Ji-xiang song Bao-an State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering/Key Laboratory of Green Pesticide and Agricultural Bioengineering Ministry of Education/Guizhou UniversityGuiyang 550025P.R.China

Plant-parasitic nematodes cause substantial economic losses to global agriculture *** use of nematicides is an effective way of controlling plant-parasitic ***,the long-term use of traditional organophosphorus and carbamate chemical nematicides can lead to increased nematode *** the increasing awareness of the necessity for the protection of the environment and human health,highly toxic nematicides no longer meet the developmental requirements of modern ***,many studies have been undertaken on the isolation and nematicidal activity of natural products against plant-parasitic nematodes and Caenorhabditis *** an important model nematode,*** plays a vital reference role in studying plant-parasitic nematodes regarding nematicidal activity,metabolic mechanism,and modes of action and *** reviewed the latest research progress of natural nematicidal active compounds against plantparasitic nematodes and *** over the past ten years,discussed the structure-activity relationship and mechanism of action,and examined the development and application of natural nematicidal active compounds.

关键词： natural products nematicides research progress plant-parasitic nematodes