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Call for Papers from Agricultural Products Processing and Storage
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《肉类研究》 北大核心 2025年第10期I0017-I0017,共1页
Agricultural Products Processing and Storage(ISSN 3059-4510,Owner:Hunan Academy of Agricultural Sciences,China.Production and hosting:Springer Nature)is an international,peer-reviewed open access journal with the aim ... Agricultural Products Processing and Storage(ISSN 3059-4510,Owner:Hunan Academy of Agricultural Sciences,China.Production and hosting:Springer Nature)is an international,peer-reviewed open access journal with the aim to offer a platform for the rapid dissemination of signifi cant,novel,and high-impact research in the fi elds of agricultural product processing science,technology,engineering,and nutrition.Additionally,supplemental issues are curated and published to facilitate in-depth discussions on special topics. 展开更多
关键词 NUTRITION SCIENCE agricultural products open access journal agricultural products processing STORAGE technology engineering
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Call for Papers from Agricultural Products Processing and Storage
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《肉类研究》 北大核心 2025年第11期I0017-I0017,共1页
Agricultural Products Processing and Storage(ISSN 3059-4510,Owner:Hunan Academy of Agricultural Sciences,China.Production and hosting:Springer Nature)is an international,peer-reviewed open access journal with the aim ... Agricultural Products Processing and Storage(ISSN 3059-4510,Owner:Hunan Academy of Agricultural Sciences,China.Production and hosting:Springer Nature)is an international,peer-reviewed open access journal with the aim to offer a platform for the rapid dissemination of signifi cant,novel,and high-impact research in the fi elds of agricultural product processing science,technology,engineering,and nutrition.Additionally,supplemental issues are curated and published to facilitate in-depth discussions on special topics. 展开更多
关键词 NUTRITION SCIENCE agricultural products open access journal agricultural products processing STORAGE technology engineering
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Call for Papers from Agricultural Products Processing and Storage
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《食品科学》 北大核心 2025年第20期I0022-I0022,共1页
Agricultural Products Processing and Storage(ISSN 3059-4510,Owner:Hunan Academy of Agricultural Sciences,China.Production and hosting:Springer Nature)is an international,peer-reviewed open access journal with the aim ... Agricultural Products Processing and Storage(ISSN 3059-4510,Owner:Hunan Academy of Agricultural Sciences,China.Production and hosting:Springer Nature)is an international,peer-reviewed open access journal with the aim to offer a platform for the rapid dissemination of signifi cant,novel,and high-impact research in the fi elds of agricultural product processing science,technology,engineering,and nutrition.Additionally,supplemental issues are curated and published to facilitate in-depth discussions on special topics. 展开更多
关键词 NUTRITION SCIENCE agricultural products open access journal agricultural products processing STORAGE technology engineering
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Call for Papers from Agricultural Products Processing and Storage
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《肉类研究》 北大核心 2025年第9期I0017-I0017,共1页
Agricultural Products Processing and Storage(ISSN 3059-4510,Owner:Hunan Academy of Agricultural Sciences,China.Production and hosting:Springer Nature)is an international,peer-reviewed open access journal with the aim ... Agricultural Products Processing and Storage(ISSN 3059-4510,Owner:Hunan Academy of Agricultural Sciences,China.Production and hosting:Springer Nature)is an international,peer-reviewed open access journal with the aim to offer a platform for the rapid dissemination of signifi cant,novel,and high-impact research in the fi elds of agricultural product processing science,technology,engineering,and nutrition.Additionally,supplemental issues are curated and published to facilitate in-depth discussions on special topics. 展开更多
关键词 NUTRITION SCIENCE agricultural products open access journal agricultural products processing STORAGE technology engineering
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Evaluation of high voltage pulse discharge in resource processing applications:A review
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作者 ZHANG Hong-hao YUAN Shuai +3 位作者 GAO Peng LI Yan-jun HAN Yue-xin DING Hao-yuan 《Journal of Central South University》 2025年第3期934-961,共28页
Breakage is an important step in the resource processing chain.However,the mechanical crushing methods commonly used today suffer from low energy efficiency and high dust levels.Promoting environmental protection and ... Breakage is an important step in the resource processing chain.However,the mechanical crushing methods commonly used today suffer from low energy efficiency and high dust levels.Promoting environmental protection and improving energy efficiency are crucial to advancing China’s circular economy.Mining companies are actively exploring novel and innovative technologies to significantly cut down on operating costs and minimize emissions of dust and pollutants generated during processing.Recently,high voltage pulse discharge(HVPD)technology has received widespread attention and has been reported to have good application prospects in resource processing.This paper presents an extensive review of the operational principles of HVPD and the unique characteristics it engenders,such as non-polluting,selective material fragmentation,pre-weakening,pre-concentration,and enhanced permeability of coal seams.Additionally,this review explores the potential and obstacles confronting HVPD in industrial contexts,offering fresh insights for HVPD optimization and providing guidance and prospects for industrial deployment and further development. 展开更多
关键词 resource processing high voltage pulse discharge selective fragmentation pre-weakening PRE-CONCENTRATION
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Intensive processing optimization of Zn-Cu fabricated by laser powder-bed fusion
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作者 YAN Yi-cheng ZHU Jiang-qi +9 位作者 YAN Yuan-ming LIU Yang LIU Ya-jun SHI Chun-bao LIU Yong LIU Min QIU Hao HUANG Qian-li YAN Xing-chen ZHANG Xiang-yu 《Journal of Central South University》 2025年第4期1194-1210,共17页
Laser powder-bed fusion(LPBF)of Zn-0.8Cu(wt.%)alloys exhibits significant advantages in the customization of biodegradable bone implants.However,the formability of LPBFed Zn alloy is not sufficient due to the spheroid... Laser powder-bed fusion(LPBF)of Zn-0.8Cu(wt.%)alloys exhibits significant advantages in the customization of biodegradable bone implants.However,the formability of LPBFed Zn alloy is not sufficient due to the spheroidization during the interaction of powder and laser beam,of which the mechanism is still not well understood.In this study,the evolution of morphology and grain structure of the LPBFed Zn-Cu alloy was investigated based on single-track deposition experiments.As the scanning speed increases,the grain structure of a single track of Zn-Cu alloy gradually refines,but the formability deteriorates,leading to the defect’s formation in the subsequent fabrication.The Zn-Cu alloys fabricated by optimum processing parameters exhibit a tensile strength of 157.13 MPa,yield strength of 106.48 MPa and elongation of 14.7%.This work provides a comprehensive understanding of the processing optimization of Zn-Cu alloy,achieving LPBFed Zn-Cu alloy with high density and excellent mechanical properties. 展开更多
关键词 laser powder-bed fusion Zn alloys single track processing parameters mechanical properties
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基于PCM-FM信号的海上动平台多站时差定位技术
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作者 杨峻巍 张旭 +1 位作者 王炯琦 高梦瑶 《电讯技术》 北大核心 2025年第5期749-755,共7页
针对海上试验靶场各类飞行器的快速搜索及落点精确测量需求,提出了一种基于脉冲编码调制-调频(Pulse-Code Modulation Frequency-Modulation,PCM-FM)信号的海上动平台多站时差定位方法,构建了海上动平台多站时差定位系统架构。通过载波... 针对海上试验靶场各类飞行器的快速搜索及落点精确测量需求,提出了一种基于脉冲编码调制-调频(Pulse-Code Modulation Frequency-Modulation,PCM-FM)信号的海上动平台多站时差定位方法,构建了海上动平台多站时差定位系统架构。通过载波平滑伪距+扼流环多径抑制技术解决海上动平台条件下站间高精度时间同步,基于常数模算法的盲均衡技术解决海上多径环境下遥测信号码间串扰,通过遥测帧多符号平滑处理降低时差测量抖动误差,最后基于高斯-牛顿迭代最小二乘法实现多站实时高精度时差定位。仿真及飞行试验结果表明,该方法在动平台条件下定位精度优于100 m,可满足海上靶场目标定位精度需求,为未来海上靶场目标回收及装备鉴定的高精度测量系统建设提供了工程参考及设计依据。 展开更多
关键词 海上动平台 海上靶场 PCM-fm信号 时差定位
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Data processing method for aerial testing of rotating accelerometer gravity gradiometer 被引量:1
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作者 QIAN Xuewu TANG Hailiang 《中国惯性技术学报》 EI CSCD 北大核心 2024年第8期743-752,共10页
A novel method for noise removal from the rotating accelerometer gravity gradiometer(MAGG)is presented.It introduces a head-to-tail data expansion technique based on the zero-phase filtering principle.A scheme for det... A novel method for noise removal from the rotating accelerometer gravity gradiometer(MAGG)is presented.It introduces a head-to-tail data expansion technique based on the zero-phase filtering principle.A scheme for determining band-pass filter parameters based on signal-to-noise ratio gain,smoothness index,and cross-correlation coefficient is designed using the Chebyshev optimal consistent approximation theory.Additionally,a wavelet denoising evaluation function is constructed,with the dmey wavelet basis function identified as most effective for processing gravity gradient data.The results of hard-in-the-loop simulation and prototype experiments show that the proposed processing method has shown a 14%improvement in the measurement variance of gravity gradient signals,and the measurement accuracy has reached within 4E,compared to other commonly used methods,which verifies that the proposed method effectively removes noise from the gradient signals,improved gravity gradiometry accuracy,and has certain technical insights for high-precision airborne gravity gradiometry. 展开更多
关键词 airborne gravity gradiometer data processing band-passing filter evaluation function
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High performance receiving and processing technology in satellite beam hopping communication
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作者 ZHAI Shenghua HUI Tengfei +3 位作者 GONG Xianfeng ZHANG Zehui GAO Xiaozheng YANG Kai 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第4期815-828,共14页
Beam-hopping technology has become one of the major research hotspots for satellite communication in order to enhance their communication capacity and flexibility.However,beam hopping causes the traditional continuous... Beam-hopping technology has become one of the major research hotspots for satellite communication in order to enhance their communication capacity and flexibility.However,beam hopping causes the traditional continuous time-division multiplexing signal in the forward downlink to become a burst signal,satellite terminal receivers need to solve multiple key issues such as burst signal rapid synchronization and high-per-formance reception.Firstly,this paper analyzes the key issues of burst communication for traffic signals in beam hopping sys-tems,and then compares and studies typical carrier synchro-nization algorithms for burst signals.Secondly,combining the requirements of beam-hopping communication systems for effi-cient burst and low signal-to-noise ratio reception of downlink signals in forward links,a decoding assisted bidirectional vari-able parameter iterative carrier synchronization technique is pro-posed,which introduces the idea of iterative processing into car-rier synchronization.Aiming at the technical characteristics of communication signal carrier synchronization,a new technical approach of bidirectional variable parameter iteration is adopted,breaking through the traditional understanding that loop struc-tures cannot adapt to low signal-to-noise ratio burst demodula-tion.Finally,combining the DVB-S2X standard physical layer frame format used in high throughput satellite communication systems,the research and performance simulation are con-ducted.The results show that the new technology proposed in this paper can significantly shorten the carrier synchronization time of burst signals,achieve fast synchronization of low signal-to-noise ratio burst signals,and have the unique advantage of flexible and adjustable parameters. 展开更多
关键词 beam-hopping high throughput satellite high per-formance reception processing
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《当代经济科学》连续入选FMS管理科学高质量期刊推荐列表
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作者 《当代经济科学》编辑部 《当代经济科学》 北大核心 2025年第4期F0003-F0003,共1页
由中国优选法统筹法与经济数学研究会、管理科学与工程学会、中国系统工程学会,三家管理科学领域国家一级学会联合研制的《FMS管理科学高质量期刊推荐列表2025》正式发布。《当代经济科学》再次成功入选该高质量期刊榜单,实现了自该列表... 由中国优选法统筹法与经济数学研究会、管理科学与工程学会、中国系统工程学会,三家管理科学领域国家一级学会联合研制的《FMS管理科学高质量期刊推荐列表2025》正式发布。《当代经济科学》再次成功入选该高质量期刊榜单,实现了自该列表2020年首次发布以来持续入选。 展开更多
关键词 fmS管理科学高质量期刊推荐列表
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人原癌基因c-fms启动子E1上游富含鸟嘌呤DNA片段d(G_(3)AG_(3)T_(2)G_(3)A_(2)G_(3))体外形成的G-四链体之间自发进行构型转换
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作者 刘芷玥 景海涛 +3 位作者 朱婷 付文强 张钠 胡文萱 《生物学杂志》 北大核心 2025年第2期7-14,共8页
F3g是源自人类原癌基因c-fms启动子E1上游的DNA短链片段d(G_(3)AG_(3)T_(2)G_(3)A_(2)G_(3))。核磁共振研究发现,F3g在近生理的K+溶液中能折叠成两种不同的G-四链体结构,并且观察到这两种G-四链体结构间存在自发转化过程。随后,利用核... F3g是源自人类原癌基因c-fms启动子E1上游的DNA短链片段d(G_(3)AG_(3)T_(2)G_(3)A_(2)G_(3))。核磁共振研究发现,F3g在近生理的K+溶液中能折叠成两种不同的G-四链体结构,并且观察到这两种G-四链体结构间存在自发转化过程。随后,利用核磁共振、圆二色谱与凝胶电泳等多种技术共同验证表明:处于动力学有利的Form 1结构为非全平行型的两层G-四链体结构;而处于热力学稳定的Form 2结构则形成了由两个全平行型三层G-四链体相互堆叠的结构。研究结果为进一步理解人类原癌基因c-fms的表达调控以及相关疾病的靶向治疗提供了一定的参考与理论基础。 展开更多
关键词 人类原癌基因c-fms DNA G-四链体 自发结构转换 核磁共振 圆二色谱
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Enhanced oxidation mechanism of arsenopyrite in two-stage oxidation process applying bio-oxidation waste solution
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作者 ZHANG Shi-qi YANG Hong-ying +3 位作者 TONG Lin-lin CHEN Guo-min KANG Guo-ai ZHAO Zhi-xin 《Journal of Central South University》 2025年第1期94-105,共12页
Applying bio-oxidation waste solution(BOS)to chemical-biological two-stage oxidation process can significantly improve the bio-oxidation efficiency of arsenopyrite.This study aims to clarify the enhanced oxidation mec... Applying bio-oxidation waste solution(BOS)to chemical-biological two-stage oxidation process can significantly improve the bio-oxidation efficiency of arsenopyrite.This study aims to clarify the enhanced oxidation mechanism of arsenopyrite by evaluating the effects of physical and chemical changes of arsenopyrite in BOS chemical oxidation stage on mineral dissolution kinetics,as well as microbial growth activity and community structure composition in bio-oxidation stage.The results showed that the chemical oxidation contributed to destroying the physical and chemical structure of arsenopyrite surface and reducing the particle size,and led to the formation of nitrogenous substances on mineral surface.These chemical oxidation behaviors effectively promoted Fe^(3+)cycling in the bio-oxidation system and weakened the inhibitory effect of the sulfur film on ionic diffusion,thereby enhancing the dissolution kinetics of the arsenopyrite.Therefore,the bio-oxidation efficiency of arsenopyrite was significantly increased in the two-stage oxidation process.After 18 d,the two-stage oxidation process achieved total extraction rates of(88.8±2.0)%,(86.7±1.3)%,and(74.7±3.0)%for As,Fe,and S elements,respectively.These values represented a significant increase of(50.8±3.4)%,(47.1±2.7)%,and(46.0±0.7)%,respectively,compared to the one-stage bio-oxidation process. 展开更多
关键词 BIO-OXIDATION ARSENOPYRITE two-stage oxidation process microbial community kinetics
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Numerical investigation on the engraving process of a pyrotechnic actuator with an improved two-phase flow model of interior ballistic
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作者 Yue Li Cong Liu +1 位作者 Cheng Cheng Genghui Jiang 《Defence Technology(防务技术)》 2025年第4期120-132,共13页
By combining with an improved model on engraving process,a two-phase flow interior ballistic model has been proposed to accurately predict the flow and energy conversion behaviors of pyrotechnic actuators.Using comput... By combining with an improved model on engraving process,a two-phase flow interior ballistic model has been proposed to accurately predict the flow and energy conversion behaviors of pyrotechnic actuators.Using computational fluid dynamics(CFD),the two-phase flow and piston engraving characteristics of a pyrotechnic actuator are investigated.Initially,the current model was utilized to examine the intricate,multi-dimensional flow,and energy conversion characteristics of the propellant grains and combustion gas within the pyrotechnic actuator chamber.It was discovered that the combustion gas on the wall's constant transition from potential to kinetic energy,along with the combined effect of the propellant motion,are what create the pressure oscillation within the chamber.Additionally,a numerical analysis was conducted to determine the impact of various parameters on the pressure oscillation and piston motion,including pyrotechnic charge,pyrotechnic particle size,and chamber structural dimension.The findings show that decreasing the pyrotechnic charge will lower the terminal velocity,while increasing and decreasing the pyrotechnic particle size will reduce the pressure oscillation in the chamber.The pyrotechnic particle size has minimal bearing on the terminal velocity.The results of this investigation offer a trustworthy forecasting instrument for comprehending and creating pyrotechnic actuator designs. 展开更多
关键词 Pyrotechnic actuator Engraving process Two-phase flow Pressure oscillation
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基于SfM与Instant-NGP的田间大豆植株三维重建方法 被引量:1
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作者 曹鑫 秦绪佳 徐晓刚 《农业工程学报》 北大核心 2025年第1期171-180,共10页
针对以往田间环境下大豆植株三维重建过程中存在的数据采集设备成本较高、重建阶段耗时较长等问题,该研究提出一种基于运动检测自适应抽帧、运动恢复结构(structure from motion,SfM)与即时神经图形原语(instant neural graphics primit... 针对以往田间环境下大豆植株三维重建过程中存在的数据采集设备成本较高、重建阶段耗时较长等问题,该研究提出一种基于运动检测自适应抽帧、运动恢复结构(structure from motion,SfM)与即时神经图形原语(instant neural graphics primitives,Instant-NGP)的田间大豆植株三维重建方法SfM-INGP。该方法旨在提供一套低成本、高效率且高质量的田间大豆植株三维重建方案。首先,在田间环境下利用消费级智能手机环绕拍摄大豆植株全景视频,并基于运动检测的自适应速率抽帧方式获取大豆植株多视角图像序列,以减少冗余数据并提升计算效率;其次,利用SfM算法从多视角图像中恢复相机位姿,生成稀疏点云,为后续重建提供位姿信息;最后,通过Instant-NGP算法对含有位姿信息的大豆植株图像进行多分辨率哈希编码,将其输入小型多层感知机进行训练,以完成高效的三维重建。试验结果表明,在重建效率方面,与多视图立体视觉(motion-multi view stereo,MVS)和神经辐射场(neural radiance fields,NeRF)方法相比,SfM-INGP的平均重建时间为2.82 min,分别大幅缩短90.7%和99.4%;在重建质量方面,SfM-INGP的平均峰值信噪比为24.47 dB,较MVS和NeRF分别有效提高15.4%和9.3%;在重建精度方面,SfM-INGP的均方误差为0.15,显著低于MVS的0.46和NeRF的0.37;在计算资源消耗方面,SfM-INGP的平均显存消耗为6.57 GB,虽略高于MVS的5.73 GB,但远低于NeRF的14.81 GB,展现了SfM-INGP方法在重建效率、质量、精度与计算资源消耗之间的良好平衡。该研究提出的方法在实际农业田间环境下通过低成本的数据采集设备,实现了高效率且高质量的田间大豆植株三维重建,为大豆信息化育种平台建设提供了重要的技术支持和数据基础,在其他田间作物的三维重建中具有广泛应用潜力,为未来大规模农业信息化建设提供可行性方案。 展开更多
关键词 图像处理 三维重建 大豆 Instant-NGP Sfm 神经辐射场
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Multi-objective optimization of grinding process parameters for improving gear machining precision
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作者 YOU Tong-fei HAN Jiang +4 位作者 TIAN Xiao-qing TANG Jian-ping LU Yi-guo LI Guang-hui XIA Lian 《Journal of Central South University》 2025年第2期538-551,共14页
The gears of new energy vehicles are required to withstand higher rotational speeds and greater loads,which puts forward higher precision essentials for gear manufacturing.However,machining process parameters can caus... The gears of new energy vehicles are required to withstand higher rotational speeds and greater loads,which puts forward higher precision essentials for gear manufacturing.However,machining process parameters can cause changes in cutting force/heat,resulting in affecting gear machining precision.Therefore,this paper studies the effect of different process parameters on gear machining precision.A multi-objective optimization model is established for the relationship between process parameters and tooth surface deviations,tooth profile deviations,and tooth lead deviations through the cutting speed,feed rate,and cutting depth of the worm wheel gear grinding machine.The response surface method(RSM)is used for experimental design,and the corresponding experimental results and optimal process parameters are obtained.Subsequently,gray relational analysis-principal component analysis(GRA-PCA),particle swarm optimization(PSO),and genetic algorithm-particle swarm optimization(GA-PSO)methods are used to analyze the experimental results and obtain different optimal process parameters.The results show that optimal process parameters obtained by the GRA-PCA,PSO,and GA-PSO methods improve the gear machining precision.Moreover,the gear machining precision obtained by GA-PSO is superior to other methods. 展开更多
关键词 worm wheel gear grinding machine gear machining precision machining process parameters multi objective optimization
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Enhanced engineering and biocidal polypropylene filaments enabling melt reduction of AgNO_(3) through PVP agent:A scalable process for the defense industry with MEX additive manufacturing
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作者 Markos Petousis Nikolaos Michailidis +7 位作者 Vassilis Papadakis Apostolos Argyros Mariza Spiridaki Nikolaos Mountakis John Valsamos Nektarios K.Nasikas Amalia Moutsopoulou Nectarios Vidakis 《Defence Technology(防务技术)》 2025年第2期52-66,共15页
This study focused on the production of polypropylene(PP)/silver(Ag)composites via additive manufacturing.This study aimed to enhance the quality of medical-grade PP in material extrusion(MEX)three-dimensional printin... This study focused on the production of polypropylene(PP)/silver(Ag)composites via additive manufacturing.This study aimed to enhance the quality of medical-grade PP in material extrusion(MEX)three-dimensional printing(3DP)by improving its mechanical properties while simultaneously adding antibacterial properties.The latter can find extremely important and versatile properties that are applicable in defense and security domains.PP/Ag nanocomposites were prepared using a novel method based on a reaction occurring while mixing appropriate quantities of the starting polymers and additives,namely polyvinylpyrrolidone(PVP)as the matrix material and silver nitrate(AgNO_(3))as the filler.This process produced three-dimensional(3D)printed filaments,which were then used to create specimens for a series of standardized tests.It was found that the mechanical properties of the nanocomposites were enhanced in relation to pristine PP,especially for the PP matrix with various loadings of AgNO_(3)and PVP,such as 5.0 wt%and 2.5 wt%,respectively.The voids,inclusions,and actual-to-nominal dimensions also showed improved results.The 3DP specimens exhibited a more effective biocidal performance against Staphylococcus aureus than Escherichia coli,which developed an inhibition zone only in the case of PP with filler loading percentages of AgNO_(3)and PVP at 10.0 wt%and 5.0 wt%,respectively Compounds possessing such properties can be beneficial for various applications requiring increased mechanical properties and biocidal capabilities,such as in the Defence or medical industries. 展开更多
关键词 Polypropylene(PP) Polyvinyl pyrrolidone(PVP) Silver nitride(AgNO_(3)) In-situ reactive melt mixing process Material extrusion(MEX)3D printing Biocidal performance
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Processing Modflow模型在预测地面沉降中的应用 被引量:12
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作者 阚京梁 罗立红 《铁道工程学报》 EI 北大核心 2010年第2期27-31,共5页
研究目的:针对开采地下水引起的区域地面沉降对线性工程的影响问题,以京津城际铁路为例,采用地下水三维渗流与地面沉降耦合模型计算软件—Processing Modflow,选择沿线地面沉降较严重区段,建立区域地下水流场与地面沉降的耦合模型,运用... 研究目的:针对开采地下水引起的区域地面沉降对线性工程的影响问题,以京津城际铁路为例,采用地下水三维渗流与地面沉降耦合模型计算软件—Processing Modflow,选择沿线地面沉降较严重区段,建立区域地下水流场与地面沉降的耦合模型,运用参数修正后的模型,进行地面沉降预测。研究结论:利用实测地面沉降值对模型进行验证,沉降中心位置及沉降量的模拟结果与实测结果基本吻合;设计不同的地下水开采方案,利用模型预测地面沉降,结果表明:合理压采地下水可以降低地面沉降量及沉降坡度,减缓地面沉降的不均匀性。 展开更多
关键词 processing MODFLOW 区域地面沉降 线性工程 耦合模型 沉降预测
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基于SFM+光学校正的小麦根系三维重建与表型提取方法
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作者 段凌凤 王新轶 +2 位作者 魏函志 王旭升 杨万能 《农业机械学报》 北大核心 2025年第3期18-26,共9页
小麦根系作为关键的水分和养分吸收器官,其表型特征对了解小麦生长状况及土壤环境具有重要意义。然而,根系地下生长的特性使得其观测面临挑战。本研究设计了一套小麦水生培养装置、基于虹吸原理的柔性换液装置及根系图像采集系统,并针... 小麦根系作为关键的水分和养分吸收器官,其表型特征对了解小麦生长状况及土壤环境具有重要意义。然而,根系地下生长的特性使得其观测面临挑战。本研究设计了一套小麦水生培养装置、基于虹吸原理的柔性换液装置及根系图像采集系统,并针对该系统开发了图像光学折射校正方法,通过SFM算法构建了根系的三维点云模型,并提取了相关表型特征。试验表明,柔性换液装置使换液前后根系图像结构相似度提高至0.98;折射校正方法使图像误差减少62%。采用提出的装置及方法对小麦根系生长发育受氮环境的影响进行了探讨。研究结果表明,在低氮条件下,小麦根系展现出更深、分布更密集的生长趋势。另外,相比于氮高效品种,氮低效品种对氮环境变化更敏感。本文提出的装置及方法有助于高通量植物根系三维表型分析。 展开更多
关键词 小麦根系 三维重建 折射校正 图像处理 表型提取 Sfm
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功能性磁共振成像(fMRI)在隐喻研究中的应用:前沿与趋向
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作者 孙毅 王硕 《外国语文》 北大核心 2025年第3期9-24,共16页
作为一种日用不觉、时学不察的认知方式,隐喻研究备受文学和修辞学的追捧,虽成果众多,但流于表象,未触及认知神经层面的探赜。自20世纪80年代以来,认知科学和体验哲学标新立异、勇立潮头,助力研究的方法也渐趋多样性、跨学科化,从行为... 作为一种日用不觉、时学不察的认知方式,隐喻研究备受文学和修辞学的追捧,虽成果众多,但流于表象,未触及认知神经层面的探赜。自20世纪80年代以来,认知科学和体验哲学标新立异、勇立潮头,助力研究的方法也渐趋多样性、跨学科化,从行为研究、认知心理学门类延伸至神经科学领域,不一而足。其中,功能性磁共振成像(fMRI)为探讨隐喻的认知神经机制提供了崭新视角和可选手段。本文基于fMRI的技术原理、指标优势与应用价值,运用CiteSpace(6.4.R1)展现近10年(2014—2025)fMRI-隐喻研究的前沿路径,首先系统梳理具身认知、脑区加工和个体差异的相关理论与研究,随后指出当前研究有待继续深挖的若干方面,特别是任务要求、隐喻类型和实验技术,最后结合热点态势对该研究加以预测展望,以期厘清fMRI-隐喻研究的最新动态并推断未来趋势,进而引起学界的更多关注与深入探讨,为隐喻跨学科研究脉络增添一条富有开拓精神的学术进路。 展开更多
关键词 fmRI 隐喻 具身认知 脑区加工 个体差异
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航空发动机燃油调节系统FMEA与模糊综合评价
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作者 张瑞鑫 李洋洋 +1 位作者 马逸超 李运华 《机床与液压》 北大核心 2025年第1期174-179,共6页
航空发动机燃油调节系统由泵源、计量活门、压差稳定活门等组成,属于液压速度伺服系统。由于其工作环境恶劣、工况复杂,存在故障隐蔽性强、交联关系复杂和故障诊断难度大等问题。通过对燃调系统进行机制分析,明确各元件的故障机制,并采... 航空发动机燃油调节系统由泵源、计量活门、压差稳定活门等组成,属于液压速度伺服系统。由于其工作环境恶劣、工况复杂,存在故障隐蔽性强、交联关系复杂和故障诊断难度大等问题。通过对燃调系统进行机制分析,明确各元件的故障机制,并采用故障失效模式与影响分析方法(FMEA),确定和识别系统中已知或潜在的故障。通过潜在故障分析,评估航空发动机故障发生概率,建立各部件的故障隶属度矩阵,并提出纠正措施与故障检测方法。通过模糊综合评价算法,实现定量的综合性分析与评价,从而保证航空发动机燃油调节系统的高可靠性运行。 展开更多
关键词 航空发动机 燃油调节系统 故障模式与影响分析 模糊综合评价 层次分析法
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