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运用多维视角融合视觉转换器的食品气调枕形包装漏气检测

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农业工程学报 2024年第3期40卷 313-320页

作者：郭向东刘天真李聪聪滕桂法河北农业大学机电工程学院保定071001 河北农业大学信息科学与技术学院保定071001 河北省农业大数据重点实验室保定071001 河北省数字农业产业技术研究院石家庄056400

食品气调枕形包装被广泛用于农产品的贮藏、运输和消费全流程,尽管工厂广泛使用的现代包装机械和人工检验手段减小了漏气风险,但是封口缺陷、贮藏和运输中的挤压、人工检验时的人为差错等造成漏气甚至瘪袋的情况时有发生,变质的袋内食... 详细信息

食品气调枕形包装被广泛用于农产品的贮藏、运输和消费全流程,尽管工厂广泛使用的现代包装机械和人工检验手段减小了漏气风险,但是封口缺陷、贮藏和运输中的挤压、人工检验时的人为差错等造成漏气甚至瘪袋的情况时有发生,变质的袋内食品既影响了消费者身体健康又导致厂商声誉受损。该文针对食品气调枕形包装的漏气检测问题,提出了一种基于多维视角融合的Vision Transformer漏气检测方法(multi-dimentional fusion vision transformer,MdF-ViT)。通过包装袋的主视角、侧视角和俯视角的融合,提取3个视角包装袋轮廓特征,综合判断包装袋形变量,完成对枕形包装的漏气检测。对样本A、样本B、样本C的测试结果表明,该种模型准确率均达到97.5%,F1值分别达到97.6%、97.6%和97.4%。该研究提出的模型可以有效应用于工厂生产并节约成本。

关键词：食品气调包装枕形包装袋检测 Vision Transformer

基于改进YOLO v4的自然场景下冬枣果实分类识别

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江苏农业科学 2024年第1期52卷 163-172页

作者：刘天真苑迎春滕桂法孟惜河北农业大学信息科学与技术学院河北保定071001 保定学院信息工程学院河北保定071000 河北省农业大数据重点实验室河北保定071001 石家庄学院未来信息技术学院河北石家庄050035

为实现冬枣园机械化自动化采摘以及冬枣树精准化管理,针对自然场景下冬枣果实的快速、准确分类识别问题,提出一种基于YOLO v4模型改进的冬枣果实分类识别模型CC-YOLO v4。利用改进的CSP跨阶段部分连接结构和多尺度特征融合的CBAM卷积注... 详细信息

为实现冬枣园机械化自动化采摘以及冬枣树精准化管理,针对自然场景下冬枣果实的快速、准确分类识别问题,提出一种基于YOLO v4模型改进的冬枣果实分类识别模型CC-YOLO v4。利用改进的CSP跨阶段部分连接结构和多尺度特征融合的CBAM卷积注意力模块,减小网络规模的同时增强特征提取能力,改善果实分类识别的误检和遮挡目标的漏检情况;采用Softmax交叉熵损失函数代替Sigmoid二元交叉熵损失函数作为分类损失函数,引入EIoU损失函数代替CIoU损失函数作为边界框回归损失,进一步改善果实分类识别的误检并提升预测框精度。试验结果表明,CC-YOLO v4模型对3类冬枣果实的查准率P均值为81.86%,平均检测精度均值mAP为82.46%,IoU均值为81.35%,模型参数量和大小分别为26.9 M和108 MB,检测速度可达28.8 F/s。与其他模型相比,本模型具有更好的分类识别能力、识别速度和较小的模型复杂度。在不同果实数量情况下进一步试验,本研究方法具有良好的精度和鲁棒性,对解决自然场景下冬枣果实的精准分类识别问题具有重要参考价值。

关键词：冬枣果实识别 YOLO v4 损失函数自然场景

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Assessment of wheat chlorophyll content by the multiple linear regression of leaf image features

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Information Processing in Agriculture 2021年第2期8卷 232-243页

作者： Yufei Song Guifa Teng Yingchun Yuan tianzhen liu Zhimei Sun College of Information Science and Technology Hebei Agricultural UniversityBaoding 071001China College of Resources and Environment Science Hebei Agricultural UniversityBaoding 071001China College of Information Engineering Baoding UniversityBaoding 071000China

The measurement of crop nutrition is considerably significant in agricultural practices,especially in the application of mechanized variable rate *** extraction and model building are two important links in crop nutrition measurement by digital *** this paper,a feature set of fusion multi-colour space in field prototype is extracted and an evaluation approach using stepwise-based ridge regression(SBRR)that uses correlation-based evaluation method is *** the image features of three known colour spaces are extracted,meanwhile a new colour space named rgb is constructed according to the characteristics that RGB colour space easily affected by *** the SBRR with nested cross validation is used to find the best evaluation *** performance evaluation,the optimal SBRR model is obtained(R^(2)=0.718 RMSE=5.111).Additionally,compared with two other nutritional evaluation approach named backpropagation artificial neural network(BP-ANN)and k-nearest neighbors(KNN),SBRR achieves better performance in both R^(2) and *** the proposed model’s reliability is verified using the image dataset taken from the same wheat field in the next *** R^(2) and RMSE values are 0.794 and 4.304,*** comparisons and verification show that our proposed SBRR approach can achieve better experimental results and can be considered a reliable and low-cost alternative for estimating the chlorophyll content of wheat leaves in field.

关键词： Wheat chlorophyll estimation Image processing Colour feature extraction SPAD Ridge regression

Three Dimensional Sulfur-doped Graphene Hydrogels with Tetrathiafulvalene for High Performance Supercapacitors

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Chinese Journal of Chemistry 2016年第1期34卷 46-52页

作者： Jingli Zhang Man Jiang Lingbao Xing Kun Qin tianzhen liu Jin Zhou Weijiang Si Hongyou Cui Shuping Zhuo School of Chemical Engineering Shandong University of Technology Zibo Shandong 255049 China Resources and Environmental Engineering Shandong University of Technology Zibo Shandong 255049 China

By using tetrathiafulvalene as reducing and doping agents, three-dimensional （3D） sulfur-doped graphene hydrogels （SGHs） were facilely prepared in mixed solvents of dimethyl formamide and water. Several investigations reveal that TTF plays a critical role in the formation of such unique 3D architecture, as it not only reduces GO to self-assembly into 3D structures, but also can be transformed to TTF^·＋ and TTF^2＋ as doping agents in the reduction process. The morphology, crystal structure, chemical bonding, elemental composition and porosity of the as-prepared SGHs have been studied. Benefiting from well-defined and cross-linked 3D porous network architectures, the supercapacitors based on the SGHs in KOH 212.5 F·g^-1 at 0.3 A·g^-1. Furthermore, this capacitance also degree of reversibility in the repetitive charge/discharge cycling electrolyte exhibited a high specific capacitance of showed good electrochemical stability and a high test.

关键词： tetrathiafulvalene graphene three-dimensional sulfur-doped graphene hydrogels supercapacitors

A Shape-Memory Deployable Subsystem with a Large Folding Ratio in China’s Tianwen-1 Mars Exploration Mission

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Engineering 2023年第9期28卷 49-57页

作者： Chengjun Zeng Liwu liu Yang Du Miao Yu Xiaozhou Xin tianzhen liu Peilei Xu Yu Yan Dou Zhang Wenxu Dai Xin Lan Fenghua Zhang Linlin Wang Xue Wan Wenfeng Bian Yanju liu Jinsong Leng Department of Astronautical Science and Mechanics Harbin Institute of TechnologyHarbin 150001China Shanghai Institute of Satellite Engineering Shanghai 201109China Center for Composite Materials and Structures Harbin Institute of TechnologyHarbin 150080China Department of Civil Engineering Harbin Institute of TechnologyWeihai 264209China

Once China’s Tianwen-1 Mars probe arrived in a Mars orbit after a seven-month flight in the deep cold space environment,it would be urgently necessary to monitor its state and the surrounding *** address this issue,we developed a flexible deployable subsystem based on shape memory polymer composites(SMPC-FDS)with a large folding ratio,which incorporates a camera and two temperature telemetry points for monitoring the local state of the Mars orbiter and the deep space ***,we report on the development,testing,and successful application of the *** reaching its Mars remote-sensing orbit,the SMPC-FDS is designed to be in a folded state with high stiffness;after reaching orbit,it is in a deployed state with a large *** transition from the folded state to the deployed state is achieved by electrically heating the shape memory polymer composites(SMPCs);during this process,the camera on the SMPC-FDS can capture the local state of the orbiter from multiple ***,temperature telemetry points on the SMPC-FDS provide feedback on the environment temperature and the temperature change of the SMPCs during the energization *** simulating a Mars on-orbit space environment,the engineering reliability of the SMPC-FDS was comprehensively verified in terms of the material properties,structural dynamic performance,and thermal vacuum deployment *** the launch of Tianwen-1 on 23 July 2020,scientific data on the temperature environment around Tianwen-1 has been successfully acquired from the telemetry points on the SMPCFDS,and the local state of the orbiter has been photographed in orbit,showing the national flag of China fixed on the orbiter.

关键词： Flexible deployable structure Shape memory polymer composite Mars exploration Temperature telemetry On-orbit deployment

Alloy/layer double hydroxide interphasic synergy via nano-heterointerfacing for highly reversible CO_(2)redox reaction in Li-CO_(2)batteries

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Nano Research 2024年第6期17卷 5206-5215页

作者： tianzhen Jian Wenqing Ma Jiagang Hou Jianping Ma Xianhong Li Haiyang Gao Caixia Xu Hong liu Institute for Advanced Interdisciplinary Research(iAIR) Collaborative Innovation Center of Technology and Equipment for Biological Diagnosis and Therapy in Universities of ShandongSchool of Chemistry and Chemical EngineeringUniversity of JinanJinan 250022China Kyiv College at Qilu University of Technology Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China State Key Laboratory of Crystal Materials Shandong UniversityJinan 250100China Shandong Sacred Sun Power Sources Co. Ltd.Qufu 273100China

Li-CO_(2)batteries are among the most intriguing techniques for balancing the carbon cycle,but are challenged by the annoyed thermodynamic barrier of the Li_(2)CO_(3)decomposition ***,we demonstrate the electrocatalytic performances of two-dimensional(2D)CoAl-layer double hydroxide(LDH)nanosheets can be significantly improved by trans-dimensional crosslinking with three-dimensional(3D)multilevel nanoporous(MP)-RuCoAl alloy(MP-RuCoAl alloy⊥CoAl-LDH).The MP-RuCoAl alloy⊥CoAl-LDH with multiscale pore channels and abundant nano-heterointerface is directly prepared by controllable etching Al from a Ru-Co-Al master alloy along with simultaneous partial oxidization of Al and Co *** MP-RuCoAl is composed of various intermetallic compounds and Ru with abundant grain boundaries,and forms numerous heterointerface with 2D CoAl-LDH *** multiscale porous metallic network benefits mass and electron transportation as well as discharge product storage and enables a rich multiphase reaction *** situ differential electrochemical mass spectrometry shows that the mass-to-charge ratio in the charging process is~0.733 which is consistent with the theoretical value of 3/4,stating that the reversible co-decomposition of Li_(2)CO_(3)and C can be achieved with the MP-RuCoAl alloy⊥*** Ketjen black(KB)/MP-RuCoAl⊥CoAl-LDH battery demonstrates a high cyclability for over 2270 h(227 cycles)with a lower voltage gap stabilized at~1.3 V at 200 mA·g^(−1).Our findings here provide useful guidelines for developing high efficiency transition metal based electrocatalysts by coupling with conductive porous substrate for impelling the development of practical Li-CO_(2)battery systems.

关键词： heterojunction interface nanoporous Li-CO_(2)battery dealloying

Free-Standing Multiscale Porous High Entropy NiFeCoZn Alloy as the Highly Active Bifunctional Electrocatalyst for Alkaline Water Splitting

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Chinese Journal of Chemistry 2024年第13期42卷 1465-1473页

作者： Qiuping Zhang Xu Wang tianzhen Jian Wenqing Ma Caixia Xu Qiuxia Zhou Hong liu Institute for Advanced Interdisciplinary Research(iAIR) Collaborative Innovation Center of Technology and Equipment for Biological Diagnosis and Therapy in Universities of ShandongSchool of Chemistry and Chemical EngineeringUniversity of JinanJinanShandong 250022China School of Medical Information and Engineering Southwest Medical UniversityLuzhouSichuan 646000China State Key Laboratory of Crystal Materials Shandong UniversityJinanShandong 250100China

In the endeavor of searching for highly active and stable electrocatalysts toward overall water splitting,high-entropy-alloys have been the intense subjects owing to their advanced physicochemical *** non-noble metal free-standing multiscale porous NiFeCoZn high-entropy-alloy is in situ constructed on the surface layer of NiZn intermetallic and Ni heterojunction over nickel foam(NiFeCoZn/NiZn-Ni/NF)by one scalable dealloying protocal to fulfill the outstanding bifunctional electrocatalytic performances toward overall water *** of the high-entropy effects and specific hierarchical porous architecture,the as-made NiFeCoZn/NiZn-Ni/NF displays high intrinsic catalytic activities and durability toward both hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)in alkaline *** particular,the in-situ construction of bimodal porous NiFeCoZn high-entropy-alloy results in the small overpotentials(η1000=254/409 mV for HER and OER),low Tafel slopes,and exceptional long-term catalytic durability for 400 ***,the electrolyzer constructed with NiFeCoZn/NiZn-Ni/NF as both cathode and anode exhibits a low cell voltage of 1.72 V to deliver the current density of 500 mA·cm^(–2) for overall water *** work not only provides a facile and scalable protocol for the preparation of self-supporting high-entropy-alloy nanocatalysts but also enlightens the engineering of high performance bifunctional electrocatalysts toward water splitting.

关键词： High-entropy-alloys Bifunctional electrocatalyst Dealloying/Electrocatalysis Oxygen evolution reaction Hydrogen evolution reaction

Catalytic asymmetric(3+3)cycloaddition between different 2-indolylmethanols

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Science China Chemistry 2024年第8期67卷 2629-2636页

作者： tianzhen Li Sijia liu Shufang Wu Qi Cheng Qun Chen Yinchun Jiao Yuchen Zhang Feng Shi School of Petrochemical Engineering School of Materials ScienceEngineeringChangzhou UniversityChangzhou 213164China Research Center of Chiral Functional Heterocycles School of Chemistry and Materials ScienceJiangsu Normal UniversityXuzhou 221116China School of Chemistry and Chemical Engineering Hunan University of Science and TechnologyXiangtan 411201China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007China

The catalytic asymmetric(3+3)cycloaddition between different 2-indolylmethanols has been established,in which a series of chiral indole-fused six-membered heterocycles were constructed in high yields with excellent *** work not only has established the first catalytic asymmetric cycloaddition between different 2-indolylmethanols but also provided a powerful strategy for constructing enantioenriched indole-fused six-membered ***,biological evaluation discovered some products with promising antitumor ***,theoretical calculations performed on the reaction pathway and activation mode provide an in-depth understanding of this catalytic asymmetric(3+3)cycloaddition among different 2-indolylmethanols,which will advance the understanding of the chemistry of indolylmethanols.

关键词： asymmetric organocatalysis chiral phosphoric acid cycloaddition enantioselectivity 2-indolylmethanol

One-Step Scalable Fabrication of Nitrogen and Chlorine Co-doped Graphene by Electrochemical Exfoliation for High-Performance Supercapacitors

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Transactions of Tianjin University 2024年第5期30卷 448-458页

作者： Qian Li Hu Zheng Binbin liu tianzhen Jian Wenqing Ma Caixia Xu Kai Wang Institute for Advanced Interdisciplinary Research(iAIR) School of Chemistry and Chemical EngineeringUniversity of JinanJinan 250022China Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China

The stacking and aggregation of graphene nanosheets have been obstacles to their application as electrode materials for microelectronic *** study deploys a one-step,scalable,facile electrochemical exfoliation technique to fabricate nitrogen(N)and chlorine(Cl)co-doped graphene nanosheets(i.e.,N-Cl-G)via the application of constant voltage on graphite in a mixture of 0.1 mol/L H_(2)SO_(4)and 0.1 mol/L NH_(4)Cl without using dangerous and exhaustive *** introduction of Cl(with its large radius)and N,both with high electrical negativity,facilitates the modulation of the electronic structure of graphene and creation of rich structural defects in ***,in the as-constructed supercapacitors,N-Cl-G exhibits a high specific capacitance of 77 F/g at 0.2 A/g and remarkable cycling stability with 91.7%retention of initial capacitance after 20,000 cycles at 10 A/***,a symmetrical supercapacitor assembled with N-Cl-G as the positive and negative electrodes(denoted as N-Cl-G//N-Cl-G)exhibits an energy density of 3.38 Wh/kg at a power density of 600 W/kg and superior cycling stability with almost no capacitance loss after 5000 cycles at 5 A/*** study provides a scalable protocol for the facile fabrication of high-performance co-doped graphene as an electrode material candidate for supercapacitors.

关键词： Graphene Electrochemical exfoliation Supercapacitor Nitrogen Chlorine