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Pressure-induced instability and its coupled aeroelasticity of inflated pillow

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Chinese Journal of Aeronautics 2022年第2期35卷 1-7页

作者： Ji ZHANG Changguo WANG jiaming guo Jiawei ZHANG National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of TechnologyHarbin 150080China Special Environments Harbin Institute of TechnologyHarbin 150080China b Center for Composite Materials and StructuresHarbin Institute of TechnologyHarbin 150001China

A floating air weapon system(such as airborne floating mines)plays an important role in modern air defense *** paper focuses on aeroelastic characteristics of airborne floating mine named inflated ***,the dynamic deployable process of the pillow and characteristics of the local instability of the edge are studied,and the evolution mechanism of wrinkles and kinks is ***,in the cruising stage,the fluid-structural-thermal coupling analysis is performed on the pillow,and the aeroelastic characteristics are ***,the shapepreserving effect of the inflated pillow during the“negative pressure”slow landing stage is *** is found that when the wind velocity is higher,the pillow has a collapsed instability(surface extrusion and contact),and when the wind velocity is lower,snap-through instability ***,for the collapsed instability,a carbon fiber skeleton is added to discrete the large global collapsed fold into small local folds,thus achieving shape-preserving effect of *** snapthrough instability,the critical internal pressure and different shape evolution under different wind velocity are *** the analysis of the mechanical mechanism and control of the structural morphological evolution,it provides theoretical guidance for the application of the curved shell structure in floating air weapon system.

关键词： Aeroelastic analysis Fluid-structural-thermal coupling analysis Inflated pillow Kink Pressure-induced instability Wrinkle

Frequency reconfigurable antenna actuated by inflated triangular structure:Design and analysis

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Chinese Journal of Aeronautics 2023年第5期36卷 280-285页

作者： jiaming guo Xinghan QIU Jiawei ZHANG Lamei ZHANG Changguo WANG School of Astronautics Harbin Institute of TechnologyHarbin 150001China National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin 150001China School of Electronics and Information Engineering Harbin Institute of TechnologyHarbin 150001China

This paper proposes a frequency reconfigurable triangular antenna actuated by an inflated triangular *** open path antenna is transformed from an open type to a closed structure by *** structures are easy to manufacture by fusing 2 inextensible membranes together along a defined pattern of ***,the prediction of their deployed shape remains a *** solve the pattern changed problem,guided by geometric analyses and local buckle characteristics,the inflated triangular structure has been designed and verified by experiment and *** the process of transformation of the antenna,the resonant frequency of the antenna is changed because this frequency is determined by the conformational *** resonant frequency changes from GHz to kHz when the design of initial structure sizes is from millimeter to *** measured peak gains,the frequency,and the radiation direction are also reconfigurable by the initial ***,the reconfigurable resonator array is presented,which is coupled to electric fields to absorb all incident *** this work,the changed pattern design by inflating is applied to the antenna design,and its frequency reconfigurability is *** the electricity performance analysis of the reconfigurable antenna,precise manufacturing will be possible and provide guidance for manufacturing frequency reconfigurable antennas.

关键词： Free kink design Frequency Reconfigurable Antenna(FRA) Inflated Return losses Thin film

我国标识“乳酸菌”“益生菌”普通食品调查研究

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食品工业科技 2024年第12期45卷 225-233页

作者：郭嘉明曹晏文戴润芳刘春杨惠茹李慧姣付莹张国华山西大学生命科学学院山西太原030031 山西省农产品质量安全中心山西太原030002

目的:分析我国添加菌种的普通食品标签标识现状,探究其存在问题,为我国含可食用菌种食品的标签标识管理提供参考。方法:通过线上及线下渠道,收集并整理标识有“活菌”“乳酸菌”“益生菌”(不包括保健食品和传统发酵食品)预包装食品的... 详细信息

目的:分析我国添加菌种的普通食品标签标识现状,探究其存在问题,为我国含可食用菌种食品的标签标识管理提供参考。方法:通过线上及线下渠道,收集并整理标识有“活菌”“乳酸菌”“益生菌”(不包括保健食品和传统发酵食品)预包装食品的标签标识信息。结果:本次调查共采集526份符合要求的样品,调查结果显示,65.24%的产品在标签或宣传用语中使用了“益生菌”术语;91.06%的样品在包装上标示了菌种名称,49.81%的样品标示了菌株名称;72.43%的样品在标签上标示了菌种量,其中95%的产品包装上标示菌种量≥106 CFU/g(CFU/mL)。此外,29.28%的样品在标签或宣传用语中使用了功能声称及类似功能声称的相关描述,46.9%的样品在标签上标明了产品的适用或不适用人群。结论:我国普通食品中添加可食用菌种产品种类丰富,菌种名称及菌种量的标示位置及标示方式多样。部分产品灭活菌种也使用“益生菌”术语,部分产品明确功能声称,我国含“乳酸菌”“益生菌”类食品标签标识的管理有待规范。

关键词：食品用菌种食品标签益生菌声称调查

基于BPNN-PID控制策略的果蔬保鲜环境参数调控优化

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华南农业大学学报 2024年第1期45卷 137-147页

作者：吕恩利蔡晋炜曾志雄蔡威谢伯铭王广海郭嘉明华南农业大学工程学院广东广州510642 岭南现代农业科学与技术广东省实验室茂名分中心广东茂名525000 广东机电职业技术学院广东广州510550

【目的】开发新的控制策略,用于解决传统控制方法果蔬保鲜环境参数因时变性、非线性、滞后性强和惯性大等特点导致的控制精度低、鲁棒性弱等问题。【方法】将传统比例−积分−微分(Proportional-integral-derivative,PID)和BP神经网络(Bac... 详细信息

【目的】开发新的控制策略,用于解决传统控制方法果蔬保鲜环境参数因时变性、非线性、滞后性强和惯性大等特点导致的控制精度低、鲁棒性弱等问题。【方法】将传统比例−积分−微分(Proportional-integral-derivative,PID)和BP神经网络(Back-propagation neural network,BPNN)算法相结合,开发一种基于BPNN-PID的控制策略,通过自主搭建的果蔬保鲜环境调控试验平台和自主设计的控制系统,研究不同控制策略对保鲜环境参数调控效果的影响。【结果】基于BPNN-PID控制策略的果蔬保鲜环境控制系统,环境温度超调量为1.7℃、稳定时间为80 min、稳态误差为±0.2℃,环境相对湿度超调量为2.8%、稳定时间为55 min,相对湿度稳定维持在80%~90%范围内。与传统PID控制策略相比,BPNN-PID控制策略环境温度超调量减小了2.1℃、稳态误差减小了0.3℃、稳定时间缩短了25 min,环境相对湿度超调量减小了2.2%、稳定时间缩短了25 min,环境参数波动幅度均有所降低。【结论】本文开发的果蔬保鲜环境控制系统呈现出良好的动态调整能力,具有较强的鲁棒性,控制性能明显提升,实现了保鲜环境参数的精准控制,满足果蔬保鲜贮藏要求。研究结果为果蔬保鲜环境参数调控提供了参考。

关键词： PID BPNN 控制系统果蔬保鲜环境参数超调量

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奥运遗产旅游情境下自豪感与敬畏感对游客遗产责任行为的影响机制研究--以地方依恋为中介

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新经济 2024年第1期 124-137页

作者：郭佳明蒋依依谢婷方琰高洁北京体育大学体育休闲与旅游学院

为探讨奥运遗产旅游情景下积极情绪对游客遗产责任行为的影响机制,本文提出自豪感、敬畏感与地方依恋和游客遗产责任行为之间的理论框架,并以首钢滑雪大跳台为例进行实证研究。结果表明:(1)自豪感直接正向影响游客遗产责任行为;(2)地方... 详细信息

为探讨奥运遗产旅游情景下积极情绪对游客遗产责任行为的影响机制,本文提出自豪感、敬畏感与地方依恋和游客遗产责任行为之间的理论框架,并以首钢滑雪大跳台为例进行实证研究。结果表明:(1)自豪感直接正向影响游客遗产责任行为;(2)地方依恋在自豪感与敬畏感对游客遗产责任行为的影响中起中介作用,具体表现在:自豪感通过自豪感→地方认同→遗产责任行为、自豪感→地方依赖→地方认同→遗产责任行为这两条路径发挥作用,敬畏感则是通过敬畏感→地方依赖→地方认同→遗产责任行为这条链式中介发挥作用。最后,本文建议旅游者行为管理可由理性管理向情感管理的新方向转变,激发游客的国家认同情感,提升目的地形象,引导游客自觉实施遗产责任行为。

关键词：奥运遗产旅游自豪感敬畏感遗产责任行为地方依恋

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ICP-MS测定铅同位素方法的建立及铅中毒儿童的溯源

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职业卫生与应急救援 2024年第3期42卷 288-294页

作者：李采霞蔡洁燕郭嘉明王致梁嘉斌广州医科大学职业与环境卫生研究所广东广州511436 广州市第十二人民医院(广州市职业病防治院) 广东广州510620

目的优化高精密度电感耦合等离子体质谱(inductively coupled plasma mass spectrometer,ICP-MS)测定铅同位素比值(lead isotope ratio,LIR)方法,用于铅中毒儿童的铅暴露溯源。方法通过数据采集参数的优化以及相关模式的选择,建立ICP... 详细信息

目的优化高精密度电感耦合等离子体质谱(inductively coupled plasma mass spectrometer,ICP-MS)测定铅同位素比值(lead isotope ratio,LIR)方法,用于铅中毒儿童的铅暴露溯源。方法通过数据采集参数的优化以及相关模式的选择,建立ICP-MS测定LIR方法。以4名住院铅中毒儿童为研究对象,采集研究对象的血样、尿样以及相关环境样品。应用已建立的LIR方法对铅中毒儿童的血样、尿样、环境样品进行分析,并利用二维溯源模型对铅中毒儿童进行铅暴露溯源。结果在仪器优化后的条件下,^(204/206)Pb、^(207/206)Pb、^(208/206)Pb实际测定值与证书值接近,分别为(0.058 88±0.000 22)、(0.915 31±0.000 97)、(2.167 02±0.001 73);^(204/206)Pb、^(207/206)Pb、^(208/206)Pb测定值的精密度分别为0.37%、0.11%、0.08%。在铅中毒患儿铅溯源中,有两名患儿体内的LIR与涂抹于身上的红丹粉的LIR相近,有两名患儿与环境铅有关。结论经优化的高精密度电感耦合等离子体质谱测定铅同位素比值方法,灵敏度高,可用于血、尿液和环境样品中铅的LIR测定,分析其来源。

关键词：铅同位素比值电感耦合等离子体质谱溯源

C_(60) as a metal-free catalyst for lithium-oxygen batteries

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Nano Research 2024年第5期17卷 3982-3987页

作者： Xinxin Zhang jiaming Tian Yu Wang Shaohua guo Yafei Li Jiangsu Collaborative Innovation Centre of Biomedical Functional Materials School of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China College of Engineering and Applied Sciences Jiangsu Key Laboratory of Artificial Functional MaterialsNational Laboratory of Solid State MicrostructuresCollaborative Innovation Center of Advanced MicrostructuresFrontiers Science Center for Critical Earth Material CyclingNanjing UniversityNanjing 210023China

Carbon materials have shown significant potential as catalysts for lithium-oxygen batteries(LOBs).However,the intrinsic carbon sites are typically inert,necessitating extensive modifications and resulting in a limited density of active *** we present C_(60) as a metal-free cathode catalyst for LOBs,using density functional theory calculations and experimental *** lithiation reactions on the pristine carbon sites of C_(60) are energetically favorable due to its curvedπ-conjugation over the pentagon-hexagon *** kinetic analysis specifically reveals low energy barriers for Li_(2)O_(2) decomposition and Li diffusion on C_(60).Consequently,C_(60) exhibits significantly higher catalytic activity than typical carbon materials such as graphene and carbon *** electrochemical measurements validate the predictions,notably demonstrating that the intrinsic activity of C_(60) is comparable to that of noble metals.

关键词： lithium-oxygen batteries C_(60) density functional theory(DFT)calculations metal-free cathode

Vacancy defect MoSeTe embedded in N and F co-doped carbon skeleton for high performance sodium ion batteries and hybrid capacitors

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Journal of Energy Chemistry 2024年第3期90卷 652-664,I0014页

作者： Dehui Yang Wentao guo Fei guo jiaming Zhu Gang Wang Hui Wang Guanghui Yuan Shenghua Ma Beibei Wang State Key Laboratory of Photon-Technology in Western China Energy International Collaborative Center on Photoelectric Technology and Nano Functional MaterialsInstitute of Photonics&Photon-TechnologyNorthwest UniversityXi’an 710127ShannxiChina Key Laboratory of Synthetic and Natural Functional Molecule Chemistry(Ministry of Education) College of Chemistry&Materials ScienceNorthwest UniversityXi’an 710127ShannxiChina School of Chemistry and Chemical Engineering Ankang Research Centre of New Nano-materials Science and TechnologyShaanxi University Innovation Research Institute of Advanced Energy Storage Materials and Battery Technology for Future IndustrializationAnkang UniversityAnkang 725000ShannxiChina

Sodium-ion batteries(SIBs) and hybrid capacitors(SIHCs) have garnered significant attention in energy storage due to their inherent advantages,including high energy density,cost-effectiveness,and enhanced ***,developing high-performance anode materials to improve sodium storage performa nce still remains a major ***,a facile one-pot method has been developed to fabricate a hybrid of MoSeTe nanosheets implanted within the N,F co-doped honeycomb carbon skeleton(MoSeTe/N,F@C).Experimental results demonstrate that the incorporation of large-sized Te atoms into MoSeTe nanosheets enlarges the layer spacing and creates abundant anion vacancies,which effectively facilitate the insertion/extraction of Na^(+) and provide numerous ion adsorption sites for rapid surface capacitive ***,the heteroatoms N,F co-doped honeycomb carbon skeleton with a highly conductive network can restrain the volume expansion and boost reaction kinetics within the *** anticipated,the MoSeTe/N,F@C anode exhibits high reversible capacities along with exceptional cycle *** coupled with Na_(3)V_(2)(PO_(4))_(3)@C(NVPF@C) to form SIB full cells,the anode delivers a reversible specific capacity of 126 mA h g^(-1) after 100 cycles at 0.1 A g^(-1).Furthermore,when combined with AC to form SIHC full cells,the anode demonstrates excellent cycling stability with a reversible specific capacity of50 mA h g^(-1) keeping over 3700 cycles at 1.0 A g^(-1).In situ XRD,ex situ TEM characterization,and theoretical calculations(DFT) further confirm the reversibility of sodium storage in MoSeTe/N,F@C anode materials during electrochemical reactions,highlighting their potential for widespread practical *** work provides new insights into the promising utilization of advanced transition metal dichalcogenides as anode materials for Na^(+)-based energy storage devices.

关键词： MoSeTe N F co-doped honeycomb carbon skeleton Sodium-ion batteries Sodium-ion hybrid capacitor

某铅蓄电池厂工人铅暴露生物标志和同位素指纹特征的研究

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职业卫生与应急救援 2024年第3期42卷 282-287页

作者：蔡洁燕郭嘉明何易楠龙传永王致梁嘉斌广州市第十二人民医院(广州市职业病防治院) 广东广州510620 广州医科大学职业与环境卫生研究所广东广州511436 英德市慢性病防治医院(英德市职业病防治所) 广东英德513000

目的探讨铅暴露工人血铅、血锌原卟啉(zinc protoporphyrin,ZPP)、尿铅、尿δ-氨基-γ-酮戊酸(δ-aminolevulinic acid,δ-ALA)水平以及铅稳定同位素的指纹特征,分析它们之间的相关性,为铅稳定同位素示踪研究和应用提供基础。方法 2021... 详细信息

目的探讨铅暴露工人血铅、血锌原卟啉(zinc protoporphyrin,ZPP)、尿铅、尿δ-氨基-γ-酮戊酸(δ-aminolevulinic acid,δ-ALA)水平以及铅稳定同位素的指纹特征,分析它们之间的相关性,为铅稳定同位素示踪研究和应用提供基础。方法 2021年6—12月,以某市某铅蓄电池厂的40名存在铅暴露的在岗工人为研究对象,采用问卷调查的形式记录其工龄、吸烟、饮酒等相关情况,测定工人血铅、尿铅、铅暴露相关生物标志的水平,以及血、尿、环境(工作场所降尘)和水等样本中铅同位素比值(lead isotope ratio,LIR)(^(207/206)Pb、^(208/206)Pb、^(204/206)Pb),并进行统计学分析。结果调查对象血铅56.0~757.6μg/L,平均(300.0±159.8)μg/L,异常率为5.0%;尿铅2.5~235.3μg/L,平均(40.1±45.2)μg/L,异常率为7.5%;ZPP水平为0.13~7.35μmol/L,平均(1.78±1.86)μmol/L,异常率为17.5%;尿δ-ALA水平为0.71~7.46 mg/L,平均(2.78±1.70)mg/L,异常率为7.5%。Pearson相关性分析结果显示,总体血铅与血ZPP、尿铅与尿δ-ALA、血铅与尿δ-ALA均为正相关关系(r=0.536、0.728、0.511,P<0.01)。不同工龄的工人血铅及血ZPP水平的差异有统计学意义(P<0.05),均表现为1~4年工龄的工人较高;不饮酒的工人血ZPP水平高于饮酒者(P<0.05)。铅暴露工人尿液的^(208/206)Pb、^(207/206)Pb均高于血液(P<0.01)。该厂自来水的^(208/206)Pb、^(207/206)Pb低于血液、尿液(P<0.01);工作场所降尘的^(208/206)Pb低于铅暴露工人血液(P<0.01),^(207/206)Pb、^(208/206)Pb均低于铅暴露工人尿液(P<0.01)。铅暴露工人血^(207/206)Pb、^(208/206)Pb与血铅水平为负相关关系(r=-0.562、-0.673,P<0.01),血^(208/206)Pb与尿δ-ALA水平为负相关关系(r=-0.416,P<0.01);尿^(207/206)Pb、^(208/206)Pb与尿铅水平为负相关关系(r=-0.613,P<0.01;r=-0.331,P<0.05),尿^(207/206)Pb与血ZPP水平为负相关关系(r=-0.636,P<0.01)。结论血铅与血ZPP和尿δ-ALA具有较好的相关性,与环境中铅同位素比值具有较好的一致性。铅暴露工人血液、尿液中铅同位素比值的差异提示铅在进入人体后可能存在“分馏”现象。

关键词：血铅尿铅血锌原卟啉尿δ-氨基-γ-酮戊酸铅同位素比值