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基于MobileNetV4-DSFPN的芍药田间机器人视觉导航
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作者 徐善永 邢雪景 +1 位作者 程军辉 张俊卿 《农机化研究》 北大核心 2026年第8期169-178,共10页
精准分割田间可行驶区域并实时提取导航线是实现农业机器人在田间自主作业的关键环节。针对芍药田间背景复杂、现有语义模型计算复杂度高、实时性差等问题,提出一种轻量化的MobileNetV4-DSFPN语义分割模型,采用改进MobileNetV4作为高效... 精准分割田间可行驶区域并实时提取导航线是实现农业机器人在田间自主作业的关键环节。针对芍药田间背景复杂、现有语义模型计算复杂度高、实时性差等问题,提出一种轻量化的MobileNetV4-DSFPN语义分割模型,采用改进MobileNetV4作为高效编码器,显著压缩了参数量,并降低了计算复杂度。解码器部分构建了基于深度可分离卷积的轻量级特征金字塔网络(DSFPN),通过横向连接与转置卷积上采样,实现了高效的多尺度特征融合。基于分割结果,通过形态学优化、鲁棒边界点检测、自适应多项式拟合生成导航线。试验表明,使用数据增强可以显著提升模型预测精度和泛化能力。消融实验表明:改进MobileNetV4编码器在精度与效率的平衡上优于其他轻量网络,DSFPN解码器在精度与标准特征金字塔网络相近的同时,参数量与计算量分别降低了38.5%、29.3%。在芍药田间路径数据集上与多种分割模型进行对比,结果表明:在精度与效率上取得了最佳平衡,类别平均像素准确率(mPA)和平均交并比(mIoU)分别达到97.16%、94.11%;导航线的平均横向偏差为0.231像素,平均角度偏差为0.842°;将算法部署于车载计算机上平均推理速度达到23.1 FPS,满足导航对实时性和准确性的要求。 展开更多
关键词 芍药田间机器人 视觉导航 MobilenetV4 特征金字塔网络 轻量化 语义分割
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老年急性脑梗死患者血清netrin-4、PARK7水平及其与早期神经功能恶化及预后的关系 被引量:1
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作者 张元超 王达岩 +1 位作者 刘庆昌 于航 《检验医学与临床》 2026年第1期74-79,共6页
目的探讨老年急性脑梗死(ACI)患者神经导向因子4(netrin-4)、人帕金森蛋白7(PARK7)水平及其与早期神经功能恶化及预后的关系。方法选取2021年2月至2023年12月该院收治的120例ACI患者作为观察组,根据美国国立卫生研究院卒中量表(NIHSS)... 目的探讨老年急性脑梗死(ACI)患者神经导向因子4(netrin-4)、人帕金森蛋白7(PARK7)水平及其与早期神经功能恶化及预后的关系。方法选取2021年2月至2023年12月该院收治的120例ACI患者作为观察组,根据美国国立卫生研究院卒中量表(NIHSS)评分将其分为重度组(NIHSS评分>15分)和轻度组(NIHSS评分≤15分);采用改良Rankin量表将其分为预后不良组(3~6级)和预后良好组(0~2级)。另选取同期在该院体检的120例健康体检者作为对照组。采用酶联免疫吸附试验检测所有研究对象血清netrin-4、PARK7水平;采用Pearson相关分析ACI患者血清netrin-4水平与PARK7水平的相关性;采用多因素Logistic回归分析ACI患者预后不良的影响因素;绘制受试者工作特征(ROC)曲线分析血清netrin-4、PARK7对ACI患者预后不良的预测价值。结果观察组血清PARK7、血肌酐水平均明显高于对照组,清蛋白(ALB)、血清netrin-4水平明显低于对照组,差异均有统计学意义(P<0.05);轻度组血清netrin-4水平明显高于重度组,血清PARK7水平明显低于重度组,差异均有统计学意义(P<0.05);预后不良组病灶最大径大于预后良好组,血肌酐、血清PARK7水平均高于预后良好组,ALB、血清netrin-4水平均低于预后良好组,差异均有统计学意义(P<0.05)。Pearson相关分析结果显示,ACI患者血清netrin-4水平与PARK7水平呈负相关(r=-0.517,P<0.001)。多因素Logistic回归分析结果显示,血清netrin-4水平升高是ACI患者预后不良的独立保护因素(P<0.05),较大的病灶最大径、血肌酐及ALB、血清PARK7水平升高均是ACI患者预后不良的独立危险因素(P<0.05)。ROC曲线分析结果显示,血清netrin-4、PARK7联合预测ACI患者预后不良的曲线下面积(AUC)为0.910,大于二者单独预测的AUC(0.854、0.837),差异均有统计学意义(Z=2.106、2.737,P<0.05)。结论ACI患者血清netrin-4水平降低,PARK7水平升高,且均与ACI患者预后有密切联系,可为临床预测ACI患者的预后提供一定参考价值。 展开更多
关键词 急性脑梗死 早期神经功能恶化 神经导向因子4 人帕金森蛋白7 预后
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A Ni(Ⅱ)metal-organic framework based on the 4,4′-biphenyldicarboxylic acid ligand and its adsorption performance for tetracycline
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作者 LIN Chuansong ZHANG Chuqing LI Shixiong 《无机化学学报》 北大核心 2026年第3期593-605,共13页
In this study,a nickel-based MOF{(NH_(2)(CH_(3))_(2))_(2)[Ni_(3)(O)(L)3(NH(CH_(3))_(2))_(3)]}_(n)(Ni_(3)-MOF),with pore sizes of approximately 1.6 nm×1.6 nm,was synthesized by reacting 4,4′-biphenyldicarboxylic ... In this study,a nickel-based MOF{(NH_(2)(CH_(3))_(2))_(2)[Ni_(3)(O)(L)3(NH(CH_(3))_(2))_(3)]}_(n)(Ni_(3)-MOF),with pore sizes of approximately 1.6 nm×1.6 nm,was synthesized by reacting 4,4′-biphenyldicarboxylic acid(H_(2)L)with Ni(NO_(3))_(2)·6H_(2)O in an N,N-dimethylformamide(DMF)solution.The nanoscale adsorbent Ni_(3)-MOF-N with a particle diameter of approximately 200 nm was prepared using Ni_(3)-MOF.It exhibited a maximum equilibrium tetracycline(TC)adsorption capacity of 358.2 mg·g^(-1)at its isoelectric point(pH=6.50),outperforming most reported MOF-based adsorbents.This exceptional performance is likely attributed to the well-matched pore size of Ni_(3)-MOF-N(1.6 nm×1.6 nm)and the molecular dimensions of TC(0.8 nm×1.2 nm),combined with the presence of partial Ni(Ⅱ)sites on the surface of Ni_(3)-MOF-N.These features collectively facilitate effective TC adsorption through a combination of pore filling,electrostatic attraction,hydrogen bonding,surface complexation,andπ-πinteractions.Recycling experiments demonstrated that Ni_(3)-MOF-N possesses excellent structural stability and consistent adsorption performance.CCDC:2481791,Ni_(3)-MOF. 展开更多
关键词 metal-organic framework ADSORPTION TETRACYCLINE wastewater treatment
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A three-dimensional zinc(Ⅱ)metal-organic framework based on nitrogen-containing ligands for the detection of 2,4-dinitrophenylhydrazine and tetracycline
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作者 WANG Xuetian WANG Jijiang +3 位作者 TANG Long YUE Erlin WANG Xiao ZHANG Yuqi 《无机化学学报》 北大核心 2026年第4期861-871,共11页
A metal-organic framework{[Zn(L)_(0.5)(1,2,4,5-tpb)_(0.5)]·DMF·3H_(2)O}_(n)(1)was synthesized by solvothermal reaction,where H4L=5,5'-(ethane-1,2-diyl)diisophthalic acid,and 1,2,4,5-tpb=1,2,4,5-tetra(pyr... A metal-organic framework{[Zn(L)_(0.5)(1,2,4,5-tpb)_(0.5)]·DMF·3H_(2)O}_(n)(1)was synthesized by solvothermal reaction,where H4L=5,5'-(ethane-1,2-diyl)diisophthalic acid,and 1,2,4,5-tpb=1,2,4,5-tetra(pyridin-4-yl)benzene.The analysis of the single crystal structure indicates that L^(4-)and 1,2,4,5-tpb are connected with Zn(Ⅱ)to form a 2D layered structure,and the layers are linked by 1,2,4,5-tpb to form a 3D structure.1 can be used as a highly selective fluorescent probe for the detection of 2,4-dinitrophenylhydrazine(DNP)and tetracycline(TET),and the detection limits were 0.013 and 0.31μmol·L^(-1),respectively.1 was applied successfully to the determination of TET content in the Yanhe River water sample.CCDC:2466221. 展开更多
关键词 metal-organic frameworks Zn(Ⅱ) crystal structure fluorescent sensing
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Dual-Signal Colorimetric/Fluorescent Detection of Vibrio parahaemolyticus in Seafood Using a Multifunctional Aptamer-Conjugated Magnetic Covalent Organic Framework-CuO/Au Nanozyme
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作者 SUN Di YANG Xuewen +6 位作者 WANG Hui LIN Hongyong HE Xiaoxia HUO Zhenting LIU Yu YU Zhongjie JIANG Wei 《食品科学》 北大核心 2026年第6期23-40,共18页
In this study,a multifunctional aptamer-conjugated magnetic covalent organic framework(COF)-CuO/Au nanozyme(MCOF-CuO/Au@apt)was developed as a“three-in-one”platform for dual-signal colorimetric and fluorescent detec... In this study,a multifunctional aptamer-conjugated magnetic covalent organic framework(COF)-CuO/Au nanozyme(MCOF-CuO/Au@apt)was developed as a“three-in-one”platform for dual-signal colorimetric and fluorescent detection of Vibrio parahaemolyticus.The nanozyme integrated magnetic separation,peroxidase-like catalytic activity,and specific target recognition through an aptamer-based strategy.Upon binding to V.parahaemolyticus,the catalytic oxidation of tetra-aminophenylethylene(TPE-4A)by the nanozyme was selectively inhibited,resulting in distinct colorimetric and fluorescent signals that significantly enhanced the detection accuracy and reliability.The proposed method exhibited high sensitivity,with limits of detection(LOD)of 21 and 7 CFU/mL for the colorimetric and fluorescent assays,respectively.The performance of this method was validated using real seafood samples,including Penaeus vannamei,Mytilus coruscus,and Crassostrea gigas,which showed high recovery rates(101.11%-107.30%)and excellent reproducibility.The system also demonstrated strong specificity and accuracy under various conditions,confirming its robustness and practical applicability.Collectively,this innovative platform presents a promising solution for the rapid,versatile,and sensitive detection of V.parahaemolyticus in seafood,with considerable potential to advance food safety diagnosis and on-site monitoring. 展开更多
关键词 Vibrio parahaemolyticus dual-signal detection aptamer-based nanozyme magnetic covalent organic framework seafood safety
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Ligand-directed construction of cobalt-oxo cluster-based organic frameworks:Structural modulation,semiconductor,and antiferromagnetic properties
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作者 SHI Jinlian LIU Xiaoru XU Zhongxuan 《无机化学学报》 北大核心 2026年第1期45-54,共10页
Under hydrothermal and solvothermal conditions,two novel cobalt-based complexes,{[Co_(2)(CIA)(OH)(1,4-dtb)]·3.2H_(2)O}n(HU23)and{[Co_(2)(CIA)(OH)(1,4-dib)]·3.5H2O·DMF}n(HU24),were successfully construct... Under hydrothermal and solvothermal conditions,two novel cobalt-based complexes,{[Co_(2)(CIA)(OH)(1,4-dtb)]·3.2H_(2)O}n(HU23)and{[Co_(2)(CIA)(OH)(1,4-dib)]·3.5H2O·DMF}n(HU24),were successfully constructed by coordinatively assembling the semi-rigid multidentate ligand 5-(1-carboxyethoxy)isophthalic acid(H₃CIA)with the Nheterocyclic ligands 1,4-di(4H-1,2,4-triazol-4-yl)benzene(1,4-dtb)and 1,4-di(1H-imidazol-1-yl)benzene(1,4-dib),respectively,around Co^(2+)ions.Single-crystal X-ray diffraction analysis revealed that in both complexes HU23 and HU24,the CIA^(3-)anions adopt aκ^(7)-coordination mode,bridging six Co^(2+)ions via their five carboxylate oxygen atoms and one ether oxygen atom.This linkage forms tetranuclear[Co4(μ3-OH)2]^(6+)units.These Co-oxo cluster units were interconnected by CIA^(3-)anions to assemble into 2D kgd-type structures featuring a 3,6-connected topology.The 2D layers were further connected by 1,4-dtb and 1,4-dib,resulting in 3D pillar-layered frameworks for HU23 and HU24.Notably,despite the similar configurations of 1,4-dtb and 1,4-dib,differences in their coordination spatial orientations lead to topological divergence in the 3D frameworks of HU23 and HU24.Topological analysis indicates that the frameworks of HU23 and HU24 can be simplified into a 3,10-connected net(point symbol:(4^(10).6^(3).8^(2))(4^(3))_(2))and a 3,8-connected tfz-d net(point symbol:(4^(3))_(2)((4^(6).6^(18).8^(4)))),respectively.This structural differentiation confirms the precise regulatory role of ligands on the topology of metal-organic frameworks.Moreover,the ultraviolet-visible absorption spectra confirmed that HU23 and HU24 have strong absorption capabilities for ultraviolet and visible light.According to the Kubelka-Munk method,their bandwidths were 2.15 and 2.08 eV,respectively,which are consistent with those of typical semiconductor materials.Variable-temperature magnetic susceptibility measurements(2-300 K)revealed significant antiferromagnetic coupling in both complexes,with their effective magnetic moments decreasing markedly as the temperature lowered.CCDC:2457554,HU23;2457553,HU24. 展开更多
关键词 semi-rigid carboxylic acid ligands three-dimensional framework tetranuclear cobalt-oxo cluster semiconductor material antiferromagnetic magnetism
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Selective Synthesis of Bio-based Benzaldehyde Using Magnetic CoFe_(2)O_(4)@Biochar(HTR)Catalyst
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作者 Wanyun Tang Yuehui Luo +2 位作者 Can Zhu Nan Huang Quanxin Li 《Chinese Journal of Chemical Physics》 2026年第1期125-135,I0034-I0041,I0043,共20页
Developing green and efficient methods to acquire lignocellulose-based chemicals with high added value is beneficial for facilitating green chemistry and sustainable development.The goal of this study is to demonstrat... Developing green and efficient methods to acquire lignocellulose-based chemicals with high added value is beneficial for facilitating green chemistry and sustainable development.The goal of this study is to demonstrate that bio-based benzaldehyde,a noteworthy high-value chemical,is able to be directionally prepared from lignocellulosic biomass.This new control-lable transformation was materialized by uniting catalytic-pyrolysis of lignocellulose to toluene intermediate and catalytic oxidation of toluene intermediate to bio-based benzalde-hyde.This work also developed a highly active magnetic catalyst(CoFe_(2)O_(4)@Biochar(HTR)),achieving 77.1%benzaldehyde selectivity and 46.7%benzaldehyde yield using this catalyst.It was found that introducing the biochar carrier into the cobalt iron composite metal oxide cat-alyst enhanced hydroxyl radical formation and bio-based benzaldehyde synthesis.Based on catalyst characterizations and hydroxyl radical analysis,potential reaction mechanism for bio-based benzaldehyde synthesis was proposed.This strategy may provide a beneficial pathway for developing high-value bio-based chemical(benzaldehyde)using renewable lignocellulosic biomass. 展开更多
关键词 Lignocellulosic biomass Bio-based benzaldehyde Selective oxidation Toluene intermediate CoFe_(2)O_(4)@Biochar(HTR)catalyst
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P4LoF: Scheduling Loop-Free Multi-Flow Updates in Programmable Networks
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作者 Jiqiang Xia Qi Zhan +2 位作者 Le Tian Yuxiang Hu Jianhua Peng 《Computers, Materials & Continua》 2026年第1期1236-1254,共19页
The rapid growth of distributed data-centric applications and AI workloads increases demand for low-latency,high-throughput communication,necessitating frequent and flexible updates to network routing configurations.H... The rapid growth of distributed data-centric applications and AI workloads increases demand for low-latency,high-throughput communication,necessitating frequent and flexible updates to network routing configurations.However,maintaining consistent forwarding states during these updates is challenging,particularly when rerouting multiple flows simultaneously.Existing approaches pay little attention to multi-flow update,where improper update sequences across data plane nodes may construct deadlock dependencies.Moreover,these methods typically involve excessive control-data plane interactions,incurring significant resource overhead and performance degradation.This paper presents P4LoF,an efficient loop-free update approach that enables the controller to reroute multiple flows through minimal interactions.P4LoF first utilizes a greedy-based algorithm to generate the shortest update dependency chain for the single-flow update.These chains are then dynamically merged into a dependency graph and resolved as a Shortest Common Super-sequence(SCS)problem to produce the update sequence of multi-flow update.To address deadlock dependencies in multi-flow updates,P4LoF builds a deadlock-fix forwarding model that leverages the flexible packet processing capabilities of the programmable data plane.Experimental results show that P4LoF reduces control-data plane interactions by at least 32.6%with modest overhead,while effectively guaranteeing loop-free consistency. 展开更多
关键词 network management update consistency programmable data plane P4
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Lane Line Detection Method for Complex Road Scenes Based on DeepLabv3+and MobilenetV4
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作者 Yingkai Ge Jiasheng Zhang +3 位作者 Jiale Zhang Zhenguo Ma Yu Liu Lihua Wang 《Computers, Materials & Continua》 2026年第4期1341-1363,共23页
With the continuous development of artificial intelligence and computer vision technology,numerous deep learning-based lane line detection methods have emerged.DeepLabv3+,as a classic semantic segmentation model,has f... With the continuous development of artificial intelligence and computer vision technology,numerous deep learning-based lane line detection methods have emerged.DeepLabv3+,as a classic semantic segmentation model,has found widespread application in the field of lane line detection.However,the accuracy of lane line segmentation is often compromised by factors such as changes in lighting conditions,occlusions,and wear and tear on the lane lines.Additionally,DeepLabv3+suffers from high memory consumption and challenges in deployment on embedded platforms.To address these issues,this paper proposes a lane line detection method for complex road scenes based on DeepLabv3+and MobileNetV4(MNv4).First,the lightweight MNv4 is adopted as the backbone network,and the standard convolutions in ASPP are replaced with depthwise separable convolutions.Second,a polarization attention mechanism is introduced after the ASPP module to enhance the model’s generalization capability.Finally,the Simple Linear Iterative Clustering(SLIC)superpixel segmentation algorithmis employed to preserve lane line edge information.MNv4-DeepLabv3+was tested on the TuSimple and CULane datasets.On the TuSimple dataset,theMean Intersection over Union(MIoU)and Mean Pixel Accuracy(mPA)improved by 1.01%and 7.49%,respectively.On the CULane dataset,MIoU andmPA increased by 3.33%and 7.74%,respectively.Thenumber of parameters decreased from 54.84 to 3.19 M.Experimental results demonstrate that MNv4-DeepLabv3+significantly optimizes model parameter count and enhances segmentation accuracy. 展开更多
关键词 Deep learning lane line detection DeepLabv3+ MobilenetV4 SLIC
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基于MobileNetV4改进的YOLOv8目标检测算法研究
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作者 张宁 周云翀 +2 位作者 徐坤财 左超超 彭如镜 《集成技术》 2026年第2期91-103,共13页
为移动设备设计的轻量级卷积神经网络具有较快的推理速度,但受到自身网络局部性约束,即仅能在一个窗口区域内捕获局部信息,导致性能下降。引入自注意力机制虽然可以捕获全局信息,但会降低检测速度。针对上述问题,本文基于YOLOv8提出一... 为移动设备设计的轻量级卷积神经网络具有较快的推理速度,但受到自身网络局部性约束,即仅能在一个窗口区域内捕获局部信息,导致性能下降。引入自注意力机制虽然可以捕获全局信息,但会降低检测速度。针对上述问题,本文基于YOLOv8提出一种对硬件友好的MobileNetV4网络架构。该结构通过引入通用倒置瓶颈搜索块,融合了倒置瓶颈、ConvNext、Feed Forward网络及一种新型的额外深度卷积变体。同时,该结构还引入了动态上采样算子,改进了上采样操作,降低了模型使用GPU的内存和延迟。此外,本文改进了YOLOv8的检测头,通过引入动态检测头,将空间感知、尺度感知和任务感知融合到一个框架中,并在目标检测头中有效地应用注意力机制,提高检测性能和效率。实验结果表明,与次优模型YOLOv8n相比,YOLOv8n_M的平均精度均值mAP50~95提升了1.3%;在模型复杂度方面,YOLOv8n_M成功压缩了36%的模型规模(参数量缩减100万),同时将计算量降低26%(十亿次浮点运算GFLOPs减少2.4单位)。本文提出的YOLOv8n_M有效减少了模型的参数量和推理时间,并在一定程度上提高了模型在不同环境下的目标检测精度。 展开更多
关键词 YOLOv8 MobilenetV4 注意力机制 移动设备 动态检测头
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4D printing of reprocessable thiocyanate covalent adaptable networks with reconfigurable shape memory ability
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作者 Ting Xu Kexiang Chen +7 位作者 Zhiyuan He Chuanzhen Zhang Xiaoyu Li Ziyan Zhang Wenbo Fan Zhishen Ge Chenhui Cui Yanfeng Zhang 《Chinese Chemical Letters》 2026年第2期505-511,共7页
Shape memory polymers used in 4D printing only had one permanent shape after molding,which limited their applications in requiring multiple reconstructions and multifunctional shapes.Furthermore,the inherent stability... Shape memory polymers used in 4D printing only had one permanent shape after molding,which limited their applications in requiring multiple reconstructions and multifunctional shapes.Furthermore,the inherent stability of the triazine ring structure within cyanate ester(CE)crosslinked networks after molding posed significant challenges for both recycling,repairing,and degradation of resin.To address these obstacles,dynamic thiocyanate ester(TCE)bonds and photocurable group were incorporated into CE,obtaining the recyclable and 3D printable CE covalent adaptable networks(CANs),denoted as PTCE1.5.This material exhibits a Young's modulus of 810 MPa and a tensile strength of 50.8 MPa.Notably,damaged printed PTCE1.5 objects can be readily repaired through reprinting and interface rejoining by thermal treatment.Leveraging the solid-state plasticity,PTCE1.5 also demonstrated attractive shape memory ability and permanent shape reconfigurability,enabling its reconfigurable 4D printing.The printed PTCE1.5 hinges and a main body were assembled into a deployable and retractable satellite model,validating its potential application as a controllable component in the aerospace field.Moreover,printed PTCE1.5 can be fully degraded into thiol-modified intermediate products.Overall,this material not only enriches the application range of CE resin,but also provides a reliable approach to addressing environmental issue. 展开更多
关键词 4D Printing Dynamic thiocyanate ester bonds Covalent adaptable networks Cyanate ester resin Shape memory
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A magnetically recyclable CoFe_(2)O_(4)/BiOBr S-scheme heterojunction for efficient photocatalytic degradation of diuron:Performance,durability and mechanism exploration
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作者 Guie Li Chunyan Yang +4 位作者 Qiu Yang Qingzhu Zheng Menghan Li Jianhua Qu Guangshan Zhang 《Chinese Chemical Letters》 2026年第1期584-597,共14页
The excessive use of pesticides has exacerbated environmental pollution due to herbicide residues,while their persistent toxicity poses serious challenges to global ecological security.A magnetically recyclable CoFe_(... The excessive use of pesticides has exacerbated environmental pollution due to herbicide residues,while their persistent toxicity poses serious challenges to global ecological security.A magnetically recyclable CoFe_(2)O_(4)/BiOBr S-scheme heterojunctions was prepared by microwave-assisted co-precipitation method for photocatalytic degradation of Diuron(DUR) in water.The formation of S-scheme heterojunction enhances electron transfer and charge separation,which was demonstrated by free radical trapping,electrochemical experiments,and DFT calculations.The magnetic CoFe_(2)O_(4)/BiOBr catalysts can achieve 99.9 %removal of diuron in 50 min under visible light irradiation.Furthermore,the system maintains stable performance across a broad p H range(3-9),enabling adaptation to diverse water environments,effective elimination of multiple pollutants,and strong resistance to ionic interference.Using magnetic recovery,CoFe_(2)O_(4)/BiOBr exhibits a high removal rate of 99 % and a markedly low ion leaching rate(<20 μg/L) after six cycles photocatalytic process,confirming its excellent stability and durability.According to HPLCQTOF-MS and DFT calculation,the main ways of DUR degradation include dechlorinated hydroxylation,dealkylation and hydroxylation of aromatic ring and side chain.Toxicity analysis showed that the toxicity of the intermediates generated during degradation was generally lower than that of DUR.The magnetic CoFe_(2)O_(4)/BiOBr S-scheme heterojunction developed in this study exhibits excellent photocatalytic performance,high applicability,good stability,and durability,providing an effective magnetic for the removal of refractory pollutants. 展开更多
关键词 CoFe_(2)O_(4)/BiOBr DIURON DURABILITY DFT calculations Photocatalytic degradation
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Facile synthesis of porous Fe_(3)O_(4)/C composites derived from waste residues of soybean and electrolytic manganese for superior electromagnetic wave absorption
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作者 Zihao Liu Kaixiong Xiang +4 位作者 Yujia Nie Yiting Cheng Shaohua Jiang Han Chen Wei Zhou 《International Journal of Minerals,Metallurgy and Materials》 2026年第2期704-715,共12页
With growing concerns regarding electromagnetic pollution,low-cost,environmentally friendly,and high-performance electromagnetic wave absorption(EWA)materials have attracted significant attention.This paper reports on... With growing concerns regarding electromagnetic pollution,low-cost,environmentally friendly,and high-performance electromagnetic wave absorption(EWA)materials have attracted significant attention.This paper reports on the synthesis of porous Fe_(3)O_(4)/C composites that incorporate dielectric and magnetic loss mechanisms via the carbothermal reduction method and optimization of waste ratio to enhance EWA performance.The Fe_(3)O_(4)/C composites with 10wt%soybean residues(Fe_(3)O_(4)/C-10),demonstrated the best EWA performance,achieving the minimum reflection loss of−56.4 dB and a bandwidth of 2.14 GHz at a thickness of 2.23 mm.This enhanced EWA performance is primarily attributable to improved impedance matching and the synergistic effect between dielectric and magnetic losses.Furthermore,radar cross-sectional simulations confirmed the practical feasibility of the porous Fe_(3)O_(4)/C composites.This study proposes a viable strategy for utilizing soybean residue and electrolytic manganese residue,highlighting their potential applications in EWA. 展开更多
关键词 biomass-derived porous carbon electrolytic manganese residue Fe_(3)O_(4) electromagnetic wave absorption
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Temperature-dependent magnetotransport properties of Fe_(2)O_(4)/Pt heterostructure
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作者 Haomang He Ruijie Xu +2 位作者 Anke Song Zhongqiang Chen Xuefeng Wang 《Chinese Physics B》 2026年第1期280-285,共6页
We report on the growth of CoFe_(2)O_(4)/Pt heterostructure and their magnetotransport properties.The magnetoresistance under high magnetic fields exhibits a sign change when the temperature increases from 5 K to 10 K... We report on the growth of CoFe_(2)O_(4)/Pt heterostructure and their magnetotransport properties.The magnetoresistance under high magnetic fields exhibits a sign change when the temperature increases from 5 K to 10 K.The anomalous Hall resistance decreases as the temperature increases.Furthermore,angle-dependent magnetoresistance indicates that the observed magnetotransport behaviors originate from the competition between the spin Hall magnetoresistance and magnetic proximity effect. 展开更多
关键词 MAGnetOTRANSPORT magnetoresistance anomalous Hall effect Fe_(2)O_(4)/Pt heterostructure magnetic proximity effect
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Magnetic-Field Modulation of Na_(3)V_(2)(PO_(4))_(3)Crystal Orientation for Enhanced Sodium-Ion Battery Performance
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作者 Pengcheng Wang Xuqi Lin +6 位作者 Houlin Cheng Ciqi Yuan Yongping Zheng Yingbin Lin Zhigao Huang Hao Chen Jiaxin Li 《Carbon Energy》 2026年第2期221-235,共15页
Na_(3)V_(2)(PO_(4))_(3)(NVP)is a promising electrode material that exhibits magnetic anisotropy;however,the potential of this magnetic anisotropy to optimize battery performance has been largely unexplored.This study ... Na_(3)V_(2)(PO_(4))_(3)(NVP)is a promising electrode material that exhibits magnetic anisotropy;however,the potential of this magnetic anisotropy to optimize battery performance has been largely unexplored.This study proposes a cost-effective and efficient method to induce the alignment of NVP along the(113)crystal plane by applying a vertical magnetic field during the slurry coating process,thereby enhancing its battery performance.Comprehensive structural characterizations and theoretical analysis elucidate the structure-activity relationship between the preferred crystal orientation and ion transport kinetics,facilitating the formation of more ordered Na+deintercalation pathways in NVP electrodes.This alignment reduces electrode tortuosity,enhances interfacial compatibility,and substantially improves battery performance,particularly in terms of high-rate cycling capability.As a result,the magnetic-field-modulated NVP(NVP-M⊥)electrode exhibits a high capacity retention of85.1%after 500 cycles at 5 C,significantly surpassing that of the pristine electrode.The NVP-M⊥electrode also demonstrates considerable reversible capacity at 40 C and maintains excellent stability under high temperature and prolonged cycling conditions.Furthermore,superior battery performance is observed in the assembled NVP-M⊥‖hard-carbon pouch cell and commercial NVP electrode following magnetic-field modulation,thereby validating the efficacy of this method.Consequently,this magnetic-field-induced crystal-orientation optimization strategy provides an innovative approach for low-cost and highthroughput preparation of high-performance sodium-ion batteries. 展开更多
关键词 battery performance magnetic‐field modulation Na_(3)V_(2)(PO_(4))_(3)cathode sodium‐ion batteries thermalsafety
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防晒剂4-甲基苄亚基樟脑的安全评价及其监管情况
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作者 塔娜 朵慧 +3 位作者 张凤兰 余振喜 李波 苏哲 《日用化学工业(中英文)》 北大核心 2026年第2期245-251,共7页
文章旨在系统梳理4-甲基苄亚基樟脑的相关研究数据,对该成分作为化妆品防晒剂的安全性进行全面评估,为其在我国的使用和监管提供科学依据。通过文献调研,从理化特性、市场应用情况、人体吸收代谢机制以及安全性等多个维度对该物质展开... 文章旨在系统梳理4-甲基苄亚基樟脑的相关研究数据,对该成分作为化妆品防晒剂的安全性进行全面评估,为其在我国的使用和监管提供科学依据。通过文献调研,从理化特性、市场应用情况、人体吸收代谢机制以及安全性等多个维度对该物质展开研究。同时,回顾欧盟消费者安全科学委员会近二十年的评估历程与态度,对欧盟、美国、加拿大、澳大利亚、日本、东盟等国家(地区)的监管现状进行总结分析。经研究发现,体内实验数据表明4-甲基苄亚基樟脑对甲状腺系统可能存在一定影响,且有相关证据显示其具有潜在的内分泌干扰特性。尽管4-甲基苄亚基樟脑在国内化妆品市场中的使用频率呈现下降趋势,但相较于欧盟市场,其使用仍较为广泛,存在一定安全风险。因此,建议监管部门对该成分的安全性进行重新评估,并在此基础上为其制定科学合理的使用限量,保障公众用妆安全。 展开更多
关键词 4-甲基苄亚基樟脑 防晒剂 安全评价 监管
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抗青枯病茄子砧木新品种南茄砧4号的选育
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作者 伍壮生 李雪峤 +3 位作者 王小娟 廖道龙 吴月燕 高芳华 《中国蔬菜》 北大核心 2026年第3期213-216,共4页
南茄砧4号是以自交系HZ201702为母本,以南茄砧2号为父本配制而成的抗青枯病茄子砧木一代杂种。中熟,生长势较强,始花节位为第8~10节,主茎较短,侧枝上有密到极密的茸毛。花紫色,以簇生花序为主,每花序着花数3朵以上。果实卵形,纵径8~10 ... 南茄砧4号是以自交系HZ201702为母本,以南茄砧2号为父本配制而成的抗青枯病茄子砧木一代杂种。中熟,生长势较强,始花节位为第8~10节,主茎较短,侧枝上有密到极密的茸毛。花紫色,以簇生花序为主,每花序着花数3朵以上。果实卵形,纵径8~10 cm,横径5~6 cm,果皮紫褐色,萼片绿紫色,果面有条纹,单果质量90~110 g。种子肾形,千粒重约3.4 g,种皮浅黄色。嫁接亲和性好,高抗青枯病,适用于南方青枯病严重地区的茄子嫁接栽培。 展开更多
关键词 茄子砧木 南茄砧4 高抗青枯病
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基于TLR-4/MyD88/NF-κB信号通路探究温针灸干预膝骨关节炎的作用机制
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作者 王树东 董宝强 +5 位作者 盛泽伟 胡哲 于冬冬 王列 丁学峰 薛亚楠 《中华中医药学刊》 北大核心 2026年第2期24-27,I0008-I0012,共9页
目的基于Toll样受体-4(Toll-like receptors 4,TLR-4)/髓样分化因子88(Myeloid differentiation factor 88,MyD88)/核转录因子-κB(Nuclear transcription factor-kappa B,NF-κB)信号通路观察温针灸对膝骨关节炎(Knee osteoarthritis,K... 目的基于Toll样受体-4(Toll-like receptors 4,TLR-4)/髓样分化因子88(Myeloid differentiation factor 88,MyD88)/核转录因子-κB(Nuclear transcription factor-kappa B,NF-κB)信号通路观察温针灸对膝骨关节炎(Knee osteoarthritis,KOA)家兔模型的调控作用,探讨温针灸治疗膝骨关节炎的作用机制。方法健康大耳白兔40只,随机分为空白组、模型组、温针灸组、西药组,每组10只,以改良Hulth法建立膝骨关节炎模型,经4周干预后,随机处死两只,病理检查出现关节软骨表面不平整、炎性细胞浸润等改变即表明造模成功。采用HE染色法观察家兔膝关节形态学变化并进行光镜软骨检测评价标准(Mankin score,Mankin’s)评分;采用免疫组化法观察家兔膝关节软骨组织TLR-4、MyD88、NF-κB的表达,并进行半定量分析;采用酶联免疫吸附(Enzyme-linked immunosorbent assay,ELISA)法检测家兔血清中白细胞介素-6(Interleukin-6,IL-6)、白细胞介素-1β(Interleukin-1β,IL-1β)、肿瘤坏死因子-α(Tumor necrosis factor-α,TNF-α)的含量;采用Wes全自动蛋白质印迹定量分析系统检测软骨组织TLR-4、MyD88、NF-κB的蛋白表达水平。结果HE染色可见空白组家兔膝关节软骨组织平整,无任何病理变化。模型组软骨组织表面粗糙,软骨细胞呈簇状堆积或减少。温针灸组以及西药组软骨组织表面欠平整,少量裂隙,伴有少量炎性细胞浸润。与空白组相比,模型组血清中IL-6、IL-1β、TNF-α含量显著升高(P<0.05),与模型组相比,温针灸组和西药组血清中IL-6、IL-1β、TNF-α含量显著下降(P<0.05);与空白组相比,模型组软骨组织TLR-4、MyD88、NF-κB蛋白表达显著升高(P<0.05),与模型组相比,温针灸组和西药组软骨组织TLR-4、MyD88、NF-κB蛋白表达显著下降(P<0.05),且温针灸组效果更为显著。结论温针灸可以通过抑制TLR-4/MyD88/NF-κB信号通路被激活,减少下游IL-6、IL-1β、TNF-α的含量以缓解炎症反应,延缓病程进展,达到治疗KOA的目的,并能够对软骨组织起到一定程度的修复作用。 展开更多
关键词 膝骨关节炎 温针灸 炎症反应 TLR-4 MYD88 NF-ΚB
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牛蒡4CL基因家族的克隆鉴定与生物信息学分析
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作者 邢艳萍 李春妍 +5 位作者 安星华 高洺泽 赵容 康廷国 窦德强 许亮 《中华中医药学刊》 北大核心 2026年第3期20-25,I0006-I0009,共10页
目的4-香豆酸:辅酶A连接酶(4-coumarate CoA ligase,4CL)是苯丙烷途径中控制木质素、木脂素等化合物生物合成的关键酶与牛蒡子显微特征石细胞发育和牛蒡苷积累密切相关,研究旨在鉴定牛蒡中的4CL基因,探索牛蒡Arctium lappa L.4CL酶基因... 目的4-香豆酸:辅酶A连接酶(4-coumarate CoA ligase,4CL)是苯丙烷途径中控制木质素、木脂素等化合物生物合成的关键酶与牛蒡子显微特征石细胞发育和牛蒡苷积累密切相关,研究旨在鉴定牛蒡中的4CL基因,探索牛蒡Arctium lappa L.4CL酶基因家族的生物学功能。方法研究对牛蒡基因组中预测的8个4CL基因编码序列(Coding sequence,CDS)进行克隆测序,对获得序列进行生物信息学分析,并对Al4CL3进行原核表达。结果鉴定得到牛蒡4CL基因家族的8个成员克隆后除Al4CL5(96%)、Al4CL8存在5个变异位点之外,其他序列与预测序列一致性均为100%;预测Al4CL3、Al4CL5、Al4CL8蛋白具有2个跨膜螺旋结构;亚细胞定位于细胞质、质膜、叶绿体和内质网;基因序列结构存在一定差异,不均匀地分布于牛蒡1、2、3、9、10和14号染色体上;Al4CL1、Al4CL6、Al4CL8氨基酸序列中存在4CL氨基酸保守域;Al4CL基因启动子区域存在多个顺式作用元件,受多种激素或胁迫诱导;系统进化分析显示Al4CL分为3个亚族,共线性分析表明Al4CL基因家族成员与刺苞菜蓟之间存在更近的亲缘关系;构建重组质粒p ET-28a-chAl4CL3,成功诱导表达出chAl4CL3蛋白,并完成纯化。结论对牛蒡4CL基因家族的挖掘与鉴定,为牛蒡木脂素的生物合成及其品质的提高提供了一定的理论依据,为深入研究Al4CL及其生物学功能提供参考。 展开更多
关键词 4-香豆酸 辅酶A连接酶 基因克隆 生物信息学分析 原核表达
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沸石作为PRB填充介质修复NH_(4)^(+)污染地下水的效果及原位再生性能
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作者 杨婷 李亚鑫 +10 位作者 刘娜 林晓君 曾经文 王秀娟 蔡倩怡 罗子峰 张苑铃 容精男 余伟达 丘锦荣 周建利 《吉林大学学报(地球科学版)》 北大核心 2026年第2期661-672,共12页
为评估沸石作为可渗透反应墙(PRB)填充介质修复NH_(4)^(+)污染地下水效果及原位再生工艺的适用性,实现沸石在去除NH_(4)^(+)污染地下水中的可持续利用,本研究基于NH_(4)^(+)折点氯化去除机理,将沸石的吸附、离子交换作用与原位氯化再生... 为评估沸石作为可渗透反应墙(PRB)填充介质修复NH_(4)^(+)污染地下水效果及原位再生工艺的适用性,实现沸石在去除NH_(4)^(+)污染地下水中的可持续利用,本研究基于NH_(4)^(+)折点氯化去除机理,将沸石的吸附、离子交换作用与原位氯化再生技术结合,通过沸石吸附、离子交换实验、动态模拟实验结合机理分析开展研究。结果表明:当沸石投加量为40g/L,初始pH=7,吸附时间为180min时,去除效率为92.47%,最大吸附量为6.22mg/g;动态模拟实验氯化再生技术可以去除99%吸附在沸石上的NH_(4)^(+),且再生液中几乎没有NH_(4)^(+)残留;沸石表面的NH_(4)^(+)先被Na+取代,然后被氧化成N2。天然沸石和改性沸石吸附柱均表现出较好的动态去除NH_(4)^(+)效果,且所提出的沸石原位再生工艺经连续循环验证运行稳定,可用于NH_(4)^(+)污染地下水的处理。 展开更多
关键词 NH_(4)^(+) 沸石 可渗透反应墙 原位再生 地下水
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