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Online diagnosis platform for tomato seedling diseases in greenhouse production

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 80-89页

作者： Xin Jin xiaowu Zhu Jiangtao Ji Mingyong li Xiaolin Xie Bo Zhao College of Agricultural Equipment Engineering Henan University of Science and TechnologyLuoyang 471003HenanChina Science&Technology Innovation Center for Completed Set Equipment Longmen LaboratoryLuoyang 471023HenanChina Institute of Mechatronics Technology and Application China Mechanized Agriculture Science Research Institute Group Co.LtdBeijing 100020China

The facility-based production method is an important stage in the development of modern agriculture,lifting natural light and temperature restrictions and helping to improve agricultural production efficiency.To address the problems of difficulty and low accuracy in detecting pests and diseases in the dense production environment of tomato facilities,an online diagnosis platform for tomato plant diseases based on deep learning and cluster fusion was proposed by collecting images of eight major prevalent pests and diseases during the growing period of tomatoes in a facility-based environment.The diagnostic platform consists of three main parts:pest and disease information detection,clustering and decision-making of detection results,and platform diagnostic display.Firstly,based on the You Only Look Once(YOLO)algorithm,the key information of the disease was extracted by adding attention module(CBAM),multi-scale feature fusion was performed using weighted bi-directional feature pyramid network(BiFPN),and the overall construction was designed to be compressed and lightweight;Secondly,the k-means clustering algorithm is used to fuse with the deep learning results to output pest identification decision values to further improve the accuracy of identification applications;Finally,a detection platform was designed and developed using Python,including the front-end,back-end,and database of the system to realize online diagnosis and interaction of tomato plant pests and diseases.The experiment shows that the algorithm detects tomato plant diseases and insect pests with mAP(mean Average Precision)of 92.7%,weights of 12.8 Megabyte(M),inference time of 33.6 ms.Compared with the current mainstream single-stage detection series algorithms,the improved algorithm model has achieved better performance;The accuracy rate of the platform diagnosis output pests and diseases information of 91.2%for images and 95.2%for videos.It is a great significance to tomato pest control research and the development of smart agriculture.

关键词： pest and disease detection YOLO diagnosis platform k-means clustering facility production base

Building Feedback-Regulation System Through Atomic Design for Highly Active SO_(2)Sensing

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Nano-Micro Letters 2024年第7期16卷 343-357页

作者： Xin Jia Panzhe Qiao xiaowu Wang Muyu Yan Yang Chen Bao-li An Pengfei Hu Bo Lu Jing Xu Zhenggang Xue Jiaqiang Xu NEST Lab Department of ChemistryCollege of SciencesShanghai UniversityShanghai 200444People’s Republic of China Shanghai Synchrotron Radiation Facility Zhangjiang LabShanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204People’s Republic of China School of Chemistry and Materials Science University of Science and Technology of ChinaHefei 230026People’s Republic of China Key Laboratory of Organic Compound Pollution Control Engineering(MOE) School of Environmental and Chemical EngineeringShanghai UniversityShanghai 200444People’s Republic of China Shanghai University Instrumental Analysis&Research Center of Shanghai UniversityShanghai 200444People’s Republic of China

Reasonably constructing an atomic interface is pronouncedly essential for surface-related gas-sensing reaction.Herein,we present an ingen-ious feedback-regulation system by changing the interactional mode between single Pt atoms and adjacent S species for high-efficiency SO_(2)sensing.We found that the single Pt sites on the MoS_(2)surface can induce easier volatiliza-tion of adjacent S species to activate the whole inert S plane.Reversely,the activated S species can provide a feedback role in tailoring the antibonding-orbital electronic occupancy state of Pt atoms,thus creating a combined system involving S vacancy-assisted single Pt sites(Pt-Vs)to synergistically improve the adsorption ability of SO_(2)gas molecules.Further-more,in situ Raman,ex situ X-ray photoelectron spectroscopy testing and density functional theory analysis demonstrate the intact feedback-regulation system can expand the electron transfer path from single Pt sites to whole Pt-MoS_(2)supports in SO_(2)gas atmosphere.Equipped with wireless-sensing modules,the final Pt1-MoS_(2)-def sensors array can further realize real-time monitoring of SO_(2)levels and cloud-data storage for plant growth.Such a fundamental understanding of the intrinsic link between atomic interface and sensing mechanism is thus expected to broaden the rational design of highly effective gas sensors.

关键词： Feedback-regulation system Atomic interface SO_(2)sensor Single-atom sensing mechanism Intelligent-sensing array

Growth Ring-dependent Fracture Toughness of Sea Urchin Spines Estimated by Boundary Effect Model

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Journal of Bionic Engineering 2022年第5期19卷 1472-1480页

作者： Xiaona liu Simin liang Yingying li Hongmei Ji xiaowu li Department of Materials Physics and Chemistry School of Material Science and EngineeringNortheastern UniversityShenyang 110819China Key Laboratory for Anistropy and Texture of Materials Ministry of EducationNortheastern UniversityShenyang 110819China State key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China

Although the fracture behavior of sea urchin spines has been extensively investigated,there is as yet a lack of quantitative estimation on the effect of growth rings on the fracture properties of sea urchin spines.In sea urchin spines,much denser pores present in growth rings rather than porous layers.The tensile strength and fracture toughness of sea urchin spine samples with different numbers of growth rings are measured by the Boundary Effect Model(BEM).The experimental results of single-edge notched three-point bending tests indicate that the BEM is an appropriate method to estimate the fracture toughness of the present porous sea urchin spines,and the number of growth rings plays an important role in the fracture properties of spines.Specifically,the tensile strength and fracture toughness of sea urchin spines can be significantly improved with the increase in the number of growth rings,and their fracture toughness can even reach a relatively high value compared with some other porous materials with an identical porosity.The present research findings are expected to provide a fundamental insight into the design of high-performance bionic materials with a highly porous structure.

关键词： Sea urchin spine Growth ring Boundary Effect Model Porous structure Tensile strength Fracture toughness

Microstructural Dependence of Friction and Wear Behavior in Biological Shells

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Journal of Renewable Materials 2023年第8期11卷 3297-3308页

作者： Xin Wang Ying Yan Hongmei Ji xiaowu li Department of Materials Physics and Chemistry School of Material Science and EngineeringNortheastern UniversityShenyang110819China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819China Key Laboratory for Anisotropy and Texture ofMaterials Ministry of EducationNortheastern UniversityShenyang110819China

As an essential renewable mineral resource,mollusk shells can be used as handicrafts,building materials,adsor-bents,etc.However,there are few reports on the wear resistance of their structures.The Vicker’s hardness and friction,and wear resistance of different microstructures in mollusk shells were comparatively studied in the pre-sent work.The hardness of prismatic structures is lower than that of cross-lamellar and nacreous structures.How-ever,the experimental results of sliding tests indicate that the prismatic structure exhibits the best anti-wear ability compared with foliated,crossed-lamellar,and nacreous structures.The anti-wear and hardness do not present a positive correlation,as the wear resistance properties of different microstructures in mollusk shells are governed jointly by organic matrix,structural arrangement,and basic building block actions.The present researchﬁndings are expected to provide fundamental insight into the design of renewable bionic materials with high wear resistance.

关键词： Mollusk shells microstructure hardness friction wear

Controlling Carbide Evolution to Improve the Ductility in High Specific Young’s Modulus Steels

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Acta Metallurgica Sinica(English Letters) 2022年第10期35卷 1703-1711页

作者： Peng Chen Xin Xu Chao lin Fuming Yang Jiachen Pang xiaowu li Hongliang Yi Department of Materials Physics and Chemistry School of Materials Science and EngineeringNortheastern UniversityShenyang110819China The State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819China Angang Steel Company limited Technology Centre Anshan114009China Key Laboratory for Anisotropy and Texture of Materials Northeastern UniversityShenyang110819China

A high specific Young’s modulus steel could be achieved by introducing a large fraction of kappa-carbides(κ-carbide),and its ductility was improved by efficiency divorced eutectoid transformation(DET)treatment.For this steel,carbon and aluminum contents affect not only the carbide fraction,but also the type and morphology of carbides,and consequently the mechanical properties.In this work,the alloy was designed by considering both the carbide morphology and Young’s modulus,and the carbides in the high specific Young’s modulus steels were adjusted by controlling carbon content in a suitable range for achieving a good combination of strength and ductility.The detailed microstructure evolution process during DET reaction was studied,and it was found that a higher austenitizing temperature and the cooling rate lower than 300℃ h^(−1) are suitable.The blocky carbides could be avoided by designing the carbon content in a limited content range.The microstructure-property relationship of the experimental steels was also discussed for giving an impetus to the future development of high specific Young’s modulus steels.

关键词： κ-carbide High aluminum High carbon Divorced eutectoid transformation Ductility

Physiological and transcriptome analyses of Chinese cabbage in response to drought stress

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Journal of Integrative Agriculture 2024年第7期23卷 2255-2269页

作者： lin Chen Chao li Jiahao Zhang Zongrui li Qi Zeng Qingguo Sun xiaowu Wang limin Zhao Lugang Zhang Baohua li State Key Laboratory for Crop Stress Resistance and High-Efficiency Production College of HorticultureNorthwest A&F UniversityYangling 712100China Institute of Vegetables and Flowers Chinese Academy of Agricultural SciencesBeijing 100081China

Chinese cabbage is an important leafy vegetable crop with high water demand and susceptibility to drought stress.To explore the molecular mechanisms underlying the response to drought,we performed a transcriptome analysis of drought-tolerant and-sensitive Chinese cabbage genotypes under drought stress,and uncovered core droughtresponsive genes and key signaling pathways.A co-expression network was constructed by a weighted gene coexpression network analysis(WGCNA)and candidate hub genes involved in drought tolerance were identified.Furthermore,abscisic acid(ABA)biosynthesis and signaling pathways and their drought responses in Chinese cabbage leaves were systemically explored.We also found that drought treatment increased the antioxidant enzyme activities and glucosinolate contents significantly.These results substantially enhance our understanding of the molecular mechanisms underlying drought responses in Chinese cabbage.

关键词： Chinese cabbage drought stress abscisic acid weighted gene co-expression network analysis glucosinolate

Microstructural Characterization and Hardness Behavior of a Biological Saxidomus purpuratus Shell

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Journal of Materials Science & Technology 2011年第2期27卷 139-146页

作者： Wen Yang Guangping Zhang Huasai liu xiaowu li Institute of Materials Physics and Chemistry College of SciencesNortheastern UniversityShenyang 110004China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Key Laboratory for Anisotropy and Texture of Materials Ministry of EducationNortheastern UniversityShenyang 110004China

The microstructures of the Saxidomus purpuratus shell were observed. It was found that the inner and middle layers of the shell are composed of crossed lamellae, while the outer layer exhibits porous structures. With the characteristic structure of each layer, the hardness of inner layer with narrow domains in crossed lamellar structure is the highest, and that of middle layer with wide domains is lower, while the outer layer has the lowest hardness. The damage morphologies of the indentations change a lot, depending not only upon the magnitude of the indentation load, but also upon the orientation between the indentation direction and the crossed lamellae in the microstructure of the shell, which illustrates the anisotropy in mechanical properties of such shells.

关键词： Saxidomus purpuratus shell Microstructure Hardness Crossed lamellar Indentation

Processing, microstructure and mechanical properties of biomedical magnesium with a specific two-layer structure

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Progress in Natural Science:Materials International 2013年第2期23卷 183-189页

作者： Xue Zhang xiaowu li Jiguang li Xudong Sun Institute of Materials Physics and Chemistry College of Sciences Northeastern University Key Laboratory for Anisotropy and Texture Engineering of Materials Ministry of Education Northeastern University

A novel magnesium based scaffold with a two-layer structure was synthesized by powder metallurgical process using salt particles as space holder. The outer layer of the scaffold shows an interconnected porous structure and the inner layer presents a compact structure reinforced by the salt particles. Such a specific structure is introduced primarily for the purpose of a better combination of biocompatibility and mechanical compatibility. Experimental results demonstrate that the structural features and mechanical properties of the magnesium based scaffold with a salt content of 30 wt% prepared by the current method are quite compatible with the cancellous bone. Such a novel Mg-based scaffold has the potential to act as degradable implants for bone substitute application.

关键词： Magnesium Salt particle Scaffold material Porous structure Mechanical property

Optimization of Grain Boundary Character Distribution in Fe-18Cr-18Mn-0.63N High-Nitrogen Austenitic Stainless Steel

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Acta Metallurgica Sinica(English Letters) 2013年第5期26卷 497-502页

作者： Feng SHI xiaowu li Yutong HU Chuan SU Chunming liU Institute of Materials Physics and Chemistry College of Sciences Northeastern University School of Materials and Metallurgy Northeastern University

Grain boundary engineering（GBE） is a practice of improving resistance to grain boundary failure of the material through increasing the proportion of low Σ coincidence site lattice（CSL） grain boundaries（special grain boundaries） in the grain boundary character distribution（GBCD）. The GBCD in a cold rolled and annealed Fe-18Cr-18Mn-0.63N high-nitrogen austenitic stainless steel was analyzed by electron back scatter difraction（EBSD）. The results show that the optimization process of GBE in the conventional austenitic stainless steel cannot be well applied to this high-nitrogen austenitic stainless steel. The percentage of low ΣCSL grain boundaries could increase from 47.3% for the solid solution treated high-nitrogen austenitic stainless steel specimen to 82.0% for the specimen after 5% cold rolling reduction and then annealing at 1423 K for 10 min.These special boundaries of high proportion efectively interrupt the connectivity of conventional high angle grain boundary network and thus achieve the GBCD optimization for the high-nitrogen austenitic stainless steel.

关键词： High nitrogen austenitic stainless steel Grain boundary character distri-bution CSL grain boundary EBSD