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基于增材制造的碳化硅双面反射镜设计与可靠性验证
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作者 王成彬 孙胜利 +2 位作者 孙小进 马孝浩 胡凯 《光学精密工程》 北大核心 2026年第1期26-34,共9页
为实现同轴四反光学系统中主镜和四镜所构成的Φ516 mm双面共体反射镜轻量化、高刚度的设计目标,提出一种在传统轻量化设计基础上,融合多参数优化与碳化硅增材制造技术的方法。基于工程经验建立反射镜初始模型,选择主要结构尺寸建立多... 为实现同轴四反光学系统中主镜和四镜所构成的Φ516 mm双面共体反射镜轻量化、高刚度的设计目标,提出一种在传统轻量化设计基础上,融合多参数优化与碳化硅增材制造技术的方法。基于工程经验建立反射镜初始模型,选择主要结构尺寸建立多参数优化模型,并基于多目标遗传算法进行结构参数优化,优化后的反射镜质量为6.8 kg,相对初始方案降低32.6%。最后,完成碳化硅双面反射镜3D打印及结构模态测试,所得一阶频率为1964 Hz。对两个镜面光学加工后,开展了重力影响试验、真空高低温试验和振动试验。结果表明,试验前后反射镜面形精度最大变化为0.001λ(λ=632 nm)。碳化硅双面反射镜结构设计和增材制造工艺具有良好的可靠性和稳定性。 展开更多
关键词 增材制造 碳化硅 双面反射镜 轻量化 可靠性验证
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融合图像和气象多源参数判定冬小麦发育期
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作者 张佩 魏晓奕 +4 位作者 张继波 陈郑盟 苗茜 谢小萍 吴洪颜 《农业工程学报》 北大核心 2026年第1期122-131,共10页
为了实现小麦发育期的快速、无损、准确的智能判定,该研究提出了“多源参数融合-参数优选降维-概率模型判定”的思路方法,基于作物冠层RGB颜色偏态分布参数和气象因子,探索了基于融合参数的贝叶斯分类算法在小麦发育期判定上的应用。在... 为了实现小麦发育期的快速、无损、准确的智能判定,该研究提出了“多源参数融合-参数优选降维-概率模型判定”的思路方法,基于作物冠层RGB颜色偏态分布参数和气象因子,探索了基于融合参数的贝叶斯分类算法在小麦发育期判定上的应用。在山东省菏泽、泰安和桓台设置观测站点,连续4 a获取冬小麦冠层高清图像及气象数据。相关性分析表明,20个冠层颜色偏态参数与4个光热累积指标均与小麦发育期显著相关。以人工观测的生育期作为先验知识,分别建立了基于冠层颜色、气象因子及二者融合的判定模型,并比较不同模型的判定效果。结果表明,以相关分析结果作为依据重新选定贝叶斯判定模型的最优输入参数组合是红通道偏度、绿通道峰度、总积温、累积光合有效辐射,优化参数后的判定模型在建模样本中的判定准确率超过90%,对跨年度和跨生态区样本亦具有良好的适用性与稳健性。该研究将冠层图像信息与气象因子相结合,借助数字图像处理与机器学习方法,有效提升了冬小麦发育期判定的精度,为作物生产的精准管理与农业智能化提供了技术支撑。 展开更多
关键词 图像 冠层 颜色 气象参数 光热 发育期 冬小麦
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基于轻量化与注意力机制的船舶除漆机器人实时目标检测
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作者 袁小芳 李潘 +1 位作者 孙荣武 许浩志 《中山大学学报(自然科学版)(中英文)》 北大核心 2026年第1期13-22,共10页
自动巡航船舶除漆机器人目标检测受外部干扰时,存在算法检测精度下降、难以达到实时性要求等问题。为了解决这些问题,首先将重参深度可分离移动网络模块(Repvit-MobileNet block)引入到YOLOV5的主干网络中,提高检测速度。其次,在骨干网... 自动巡航船舶除漆机器人目标检测受外部干扰时,存在算法检测精度下降、难以达到实时性要求等问题。为了解决这些问题,首先将重参深度可分离移动网络模块(Repvit-MobileNet block)引入到YOLOV5的主干网络中,提高检测速度。其次,在骨干网络每个阶段后增加位置注意力机制,扩大模型的全局感受野,提升模型的目标定位及抗干扰能力。然后,将卷积块注意力模块(CBMA)引入到颈部网络中,通过融合CBMA模块增强特征提取能力,提高网络模型的检测性能。最后,提出了一种Refine-Loss损失函数,通过优化预测框和真实框的几何关系、兼顾IOU的权重和置信度信息,提高对机器人目标位置的检测精度。在船舶机器人实验数据集中进行测试与验证,结果表明:融合Repvit-MobileNet block与注意力机制的YOLOV5轻量化网络平均检测精度达到了84.1%,在边缘设备上的推理运算速度达到了26.6 f/s,满足船舶除漆机器人目标检测工业应用的需求。 展开更多
关键词 除漆机器人 轻量化 注意力机制 目标检测
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光暴露对心力衰竭模型大鼠神经递质释放的影响及其分子机制
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作者 阮琳 李佳 +5 位作者 施丽南 朱红 吴东宁 郑迪 李雨鹏 赵妍 《中国组织工程研究》 北大核心 2026年第18期4649-4662,共14页
背景:心力衰竭发生发展与神经内分泌系统的异常激活密切相关。研究表明光暴露能够降低大鼠大脑中的多巴胺水平,进一步增强下丘脑室旁核内多巴胺能神经元的活动,从而促进促肾上腺皮质激素释放因子的释放。现并无直接证据证实光暴露会诱... 背景:心力衰竭发生发展与神经内分泌系统的异常激活密切相关。研究表明光暴露能够降低大鼠大脑中的多巴胺水平,进一步增强下丘脑室旁核内多巴胺能神经元的活动,从而促进促肾上腺皮质激素释放因子的释放。现并无直接证据证实光暴露会诱发心力衰竭。目的:探究光暴露对心力衰竭模型大鼠神经递质释放的影响及其分子机制,并进行细胞学验证。方法:①动物实验:将行心力衰竭造模的SD大鼠分为模型组、光暴露模型组、光暴露治疗组,将假手术大鼠分为光暴露对照组和空白组,每组各6只。8周实验结束后,使用ELISA检测光暴露对心衰大鼠血清神经递质、激素水平的影响,苏木精-伊红染色观察心脏病理变化;Western Blot检测核因子E2相关因子2/血红素氧化酶1/磷酸酰胺腺嘌呤二核苷酸醌氧化还原酶1信号通路的调节作用。②细胞实验:将小鼠心肌细胞(HL-1细胞)分为空白组、5-羟色胺高剂量对照组(5-羟色胺500 mg/mL)、脂多糖低剂量组(脂多糖1μg/mL)、脂多糖+5-羟色胺高剂量组(5-羟色胺500 mg/mL+脂多糖1μg/mL)、ML385组(脂多糖1μg/mL+5-羟色胺500 mg/mL+核因子E2相关因子2抑制剂ML385为2.5μg/mL)、白藜芦醇组(脂多糖1μg/mL+5-羟色胺500 mg/mL+核因子E2相关因子2激动剂白藜芦醇30μg/mL),干预36 h,考察各干预条件对于细胞增殖的影响,利用Western Blot方法,验证5-羟色胺对HL-1细胞核因子E2相关因子2/血红素氧化酶1/磷酸酰胺腺嘌呤二核苷酸醌氧化还原酶1信号轴的影响。结果与结论:①光暴露能提升心力衰竭模型大鼠血清中的去甲肾上腺素和5-羟色胺水平,加剧心脏损伤;光暴露模型组及模型组心肌组织病理均呈现了明显的损伤,细胞出现了肿胀、核皱缩、空泡等现象;光暴露治疗组大鼠心肌细胞的损伤得到了明显的缓解;光暴露对照组的血管紧张素转换酶2蛋白表达低于空白组(P<0.05)而高于模型组(P<0.05),而Mas、c-fos及血红素氧化酶1表达与空白组相比虽有所下调,但差异无显著性意义(P>0.05)。在光暴露模型组中,血管紧张素转换酶2、Mas、核因子E2相关因子2及血红素氧化酶1蛋白表达均较空白组显著下调(P<0.05)。与光暴露模型组相比,光暴露治疗组中核因子E2相关因子2/血红素氧化酶1/磷酸酰胺腺嘌呤二核苷酸醌氧化还原酶1信号通路相关蛋白表达均明显上调(P<0.05)。②细胞实验显示5-羟色胺增加了脂多糖所致的心肌细胞损伤,且该损伤效应与核因子E2相关因子2/血红素氧化酶1/磷酸酰胺腺嘌呤二核苷酸醌氧化还原酶1信号通路的抑制相关。结论:过度的光暴露可能通过调节神经递质组成,介导核因子E2相关因子2/血红素氧化酶1/磷酸酰胺腺嘌呤二核苷酸醌氧化还原酶1信号通路,加速心力衰竭的进程。 展开更多
关键词 光暴露 心力衰竭 神经递质 5-羟色胺 心肌细胞损伤 核因子E2相关因子2
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咖啡渣生物炭与钼酸银复合可见光催化剂制备及其光催化性能研究
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作者 李冬梅 吴汉杰 +7 位作者 蒋树贤 贺帅 孔悦颖 李弈锴 朱俊宇 刘子业 王欣玲 戴自强 《环境科学学报》 北大核心 2026年第1期71-84,共14页
以废咖啡渣(SCG)为主要材料,经煅烧后获得咖啡渣生物炭(CGC).采用化学沉淀法将CGC与钼酸银(Ag_(2)MoO_(4),简称AM)复合形成CGC@AM可见光催化剂.通过改变CGC与AM的质量比,探究CGC@AM的最佳合成条件及其对罗丹明B(RhB)的光催化活性与降解... 以废咖啡渣(SCG)为主要材料,经煅烧后获得咖啡渣生物炭(CGC).采用化学沉淀法将CGC与钼酸银(Ag_(2)MoO_(4),简称AM)复合形成CGC@AM可见光催化剂.通过改变CGC与AM的质量比,探究CGC@AM的最佳合成条件及其对罗丹明B(RhB)的光催化活性与降解性能.结果表明:(1)CGC是一种介体大孔吸附剂,具有层状的不定形碳结构和芳香结构,表面带有C=O、C-O、OH-等活性官能团.同时,CGC具有半导体特性,导带和价带分别为-0.41 eV和1.72 eV.但因CGC表面具有大量的陷阱态,使其光生载流子平均寿命短(仅为0.38 ns),导致光催化活性弱.(2)CGC∶AM质量比为10∶9时,CGC与AM复合形成的光催化剂活性最强(CGC@AM_(OPT)).CGC@AM_(OPT)最大光吸收带为472 nm,带隙能量为2.63eV.其对罗丹明B的降解率高达99.7%(可见光照时长40 min);(3)CGC@AM致密的芳香结构,使其电子转移效率和电子存储能力显著提升,电子-空穴复合率下降明显;另外,CGC@AM具有开放式的蜂窝状结构,可见光利用率增强.(4)CGC@AM_(OPT)光催化稳定性高,经过5次循环实验后,其对RhB的光降解率仍能达到88.91%;(5)CGC与AM复合后生成大量氧空位(OVs),诱导AM表面产生缺陷,促进光生电子-空穴对的分离,最终促进以·O2-为主、·OH为辅的活性自由基生成. 展开更多
关键词 炭化咖啡渣 CGC@AM复合光催化剂 表面缺陷 可见光催化活性 降解性能
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基于几何特征分析法的焊缝特征点提取
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作者 王海舰 何金泽 +1 位作者 高兴宇 何新凯 《焊接》 2026年第1期48-54,共7页
【目的】旨在解决角接、搭接以及V形坡口典型焊缝特征点提取过程复杂的问题。【方法】提出了一种基于直线拟合的几何特征分析法,利用线结构光的激光条纹在图像里的特征,对图像进行预处理和条纹中心线提取。首先将所有提取的n个条纹中心... 【目的】旨在解决角接、搭接以及V形坡口典型焊缝特征点提取过程复杂的问题。【方法】提出了一种基于直线拟合的几何特征分析法,利用线结构光的激光条纹在图像里的特征,对图像进行预处理和条纹中心线提取。首先将所有提取的n个条纹中心点按坐标从小到大排序,在这几种焊缝特征上,利用点到直线距离公式判断关键点n0,从而将条纹中心点集进行划分,并对划分后的点集分别进行直线拟合,最后通过两直线求交点得出特征点。【结果】结果表明,该方法过程简单且能够有效检测典型焊缝上的特征点信息,且特征点最大提取误差为0.273 mm,满足焊缝检测试验要求。【结论】该方法能快速且准确地划分特征直线所属点集,并能检测出角接、搭接和V形坡口等多种类型焊缝的特征点,具有良好的适用性。 展开更多
关键词 特征提取 线结构光 中心线提取 几何特征 直线拟合 焊缝检测
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Comparing the Indoor and Solar Performance of Light-Concentrating Waveguide-Encoded Lattice Slim Films
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作者 Takashi Lawson Kathryn A.Benincasa +7 位作者 Anjilee Manhas Fariha Mahmood Helen Tunstall-García Zhihang Wang Zhongjin Shen Marina Freitag Kalaichelvi Saravanamuttu Rachel C.Evans 《Carbon Energy》 2026年第1期187-196,共10页
Although multicrystalline Si photovoltaics have been extensively studied and applied in the collection of solar energy,the same systems suffer significant efficiency losses in indoor settings,where ambient light condi... Although multicrystalline Si photovoltaics have been extensively studied and applied in the collection of solar energy,the same systems suffer significant efficiency losses in indoor settings,where ambient light conditions are considerably smaller in intensity and possess greater components of non-normal incidence.Yet,indoor light-driven,stand-alone devices can offer sustainable advances in next-generation technologies such as the Internet of Things.Here,we present a non-invasive solution to aid in photovoltaic indoor light collection—radially distributed waveguide-encoded lattice(RDWEL)slim films(thickness 1.5 mm).Embedded with a monotonical radial array of cylindrical waveguides(±20°),the RDWEL demonstrates seamless light collection(FoV(fields of view)=74.5°)and imparts enhancements in JSC(short circuit current density)of 44%and 14%for indoor and outdoor lighting conditions,respectively,when coupled to a photovoltaic device and compared to an unstructured but otherwise identical slim film coating. 展开更多
关键词 indoor light light concentrators optical thin films PHOTOPATTERNING photovoltaics self-induced waveguides solar energy
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Improving Efficiency of Light Pressure Electric Generator Using Graphene Oxide Nanospacer Between Ag Nanoparticles
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作者 Ha Young Lee Sung-Hyun Kim +3 位作者 Sun-Lyeong Hwang Hyung Soo Ahn Heedae Kim Sam Nyung Yi 《Carbon Energy》 2026年第1期38-47,共10页
Improving device efficiency is fundamental for advancing energy harvesting technology,particularly in systems designed to convert light energy into electrical output.In our previous studies,we developed a basic struct... Improving device efficiency is fundamental for advancing energy harvesting technology,particularly in systems designed to convert light energy into electrical output.In our previous studies,we developed a basic structure light pressure electric generator(Basic-LPEG),which utilized a layered configuration of Ag/Pb(Zr,Ti)O_(3)(PZT)/Pt/GaAs to generate electricity based on light-induced pressure on the PZT.In this study,we sought to enhance the performance of this Basic-LPEG by introducing Ag nanoparticles/graphene oxide(AgNPs/GO)composite units(NP-LPEG),creating upgraded harvesting device.Specifically,by depositing the AgNPs/GO units twice onto the Basic-LPEG,we observed an increase in output voltage and current from 241 mV and 3.1μA to 310 mV and 9.3μA,respectively,under a solar simulator.The increase in electrical output directly correlated with the intensity of the light pressure impacting the PZT,as well as matched the Raman measurements,finite-difference time-domain simulations,and COMSOL Multiphysics Simulation.Experimental data revealed that the enhancement in electrical output was proportional to the number of hot spots generated between Ag nanoparticles,where the electric field experienced substantial amplification.These results underline the effectiveness of AgNPs/GO units in boosting the light-induced electric generation capacity,thereby providing a promising pathway for high-efficiency energy harvesting devices. 展开更多
关键词 Ag nanoparticles energy harvesting graphene oxide light pressure PIEZOELECTRIC
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UV-B and mechanical wounding synergistically induce afarnesene biosynthesis via CsHY5-CsMYC2 cooperation during oolong tea processing
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作者 Jingjie Cao Dandan Li +5 位作者 Xiaohui Wang Xin He Ying Sun Xin Cheng Xiaochun Wan Linlin Liu 《Horticultural Plant Journal》 2026年第1期161-171,共11页
UV-B application enhances the aroma quality of oolong tea;however,the underlying regulatory mechanism remains unclear.This study investigates the regulatory role of UV-B in the biosynthesis of a-farnesene,an important... UV-B application enhances the aroma quality of oolong tea;however,the underlying regulatory mechanism remains unclear.This study investigates the regulatory role of UV-B in the biosynthesis of a-farnesene,an important floral and fruity characteristic aroma.UV-B treatment significantly improved the aroma quality of‘Foshou’and‘Yuquan’oolong teas,increasing a-farnesene levels by 1.8-and 1.4-fold,respectively.The a-farnesene synthase(CsAFS),ELONGATED HYPOCOTYL 5(CsHY5),and myelocytomatosis protein 2(CsMYC2)exhibited a highly correlated expression pattern closely associated with a-farnesene accumulation.Single-factor treatment revealed that CsAFS expression was induced by both UV-B and mechanical wounding,with CsHY5 predominantly responding to UV-B radiation,while CsMYC2 primarily responded to tumbling-induced mechanical wounding signal.Transient suppression of CsHY5 in tea leaves reduced the expression of both CsAFS and CsMYC2 whereas CsMYC2 suppression decreased CsAFS expression.G-box motifs were identified in promoters of CsMYC2 and CsAFS,and the dual-luciferase reporter assay(LUC)and electrophoretic mobility shift assays(EMSA)demonstrated direct binding functions of CsHY5 to CsAFS and CsMYC2 promoters,as well as CsMYC2 to the CsAFS promoter.Based on sensory evaluation,odourant quantification,gene expression,and molecular functional analysis,we propose that UV-B radiation and tumbling-induced wounding signals synergistically regulate a-farnesene biosynthesis through a coordinated interaction of CsHY5 and CsMYC2 during oolong tea processing.These findings improve our understanding of flavour formation during oolong tea production and also provide novel insights into artificial light application in tea manufacturing. 展开更多
关键词 Camellia sinensis Aroma formation a-farnesene synthase Light Abiotic stress
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Visible light photocatalytic enhanced heterogeneous cobalt catalyzed peroxymonosulfate synergistic process to degradation atrazine:Efficiency,influencing factors,by-products removal and mechanism
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作者 Qingkong Chen Jieyu Xia +3 位作者 Fengjun Liu Jianping Fan Peng Yan Mika Sillanpää 《Journal of Environmental Sciences》 2026年第1期166-177,共12页
This study developed a novel heterogeneous Vis-Photo+Fenton-like system by integrating visible-light-responsive Co_(3)O_(4)/TiO_(2) photocatalysis with peroxymonosulfate(PMS)activation for efficient atrazine(ATZ)degra... This study developed a novel heterogeneous Vis-Photo+Fenton-like system by integrating visible-light-responsive Co_(3)O_(4)/TiO_(2) photocatalysis with peroxymonosulfate(PMS)activation for efficient atrazine(ATZ)degradation.The synergistic process achieved complete ATZ removal within 60 min under near-neutral pH(6.9),outperform-ing individual Fenton-like(39%)and photocatalytic(24%)processes.Key factors influencing the degradation efficiency included light sources(UV>visible),pH(optimal at 6.9),catalyst dosage(0.01 g Co_(3)O_(4)/TiO_(2)),and PMS:ATZ molar ratio(1:2).The system exhibited a synergistic coefficient of 5.03(degradation)and 1.97(miner-alization),attributed to enhanced radical generation and accelerated Co^(3+)/Co^(2+)redox cycling through photoin-duced electron transfer.Intermediate analysis revealed dealkylation,dechlorination,and oxidation pathways,with reduced toxicity of by-products(e.g.,CEAT,CIAT)confirmed by ecotoxicity assessments.The mineralization efficiency(Vis-Photo+Fenton-like)reached 83.1%,significantly higher than that of standalone processes(Fenton-like:43.2%;photocatalysis:30.5%).The catalyst demonstrated excellent stability(nearly 90%recov-ery,<1μg/L Co leaching)and practical applicability.This study provides an efficient,sludge-free,and solar-compatible strategy for eliminating persistent herbicides in water treatment. 展开更多
关键词 Synergistic effect Sulfate radical FENTON-LIKE PHOTOCATALYSIS Visible light Atrazine(ATZ)
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Ultrastructure and key identification points of fossilized Os Draconis in traditional Chinese medicine
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作者 Dong-Han Bai Zi Xing +5 位作者 Zi-Hao Zhang Zhi-Jie Zhang Da-Jun Lu Nan-Xi Huang Qiao-Chu Wang Lu Luo 《Traditional Medicine Research》 2026年第1期39-46,共8页
Background:The medicinal material known as Os Draconis(Longgu)originates from fossilized remains of ancient mammals and is widely used in treating emotional and mental conditions.However,fossil resources are nonrenewa... Background:The medicinal material known as Os Draconis(Longgu)originates from fossilized remains of ancient mammals and is widely used in treating emotional and mental conditions.However,fossil resources are nonrenewable,and clinical demand is increasingly difficult to meet,leading to a proliferation of counterfeit products.During prolonged geological burial,static pressure from the surrounding strata severely compromises the microstructural integrity of osteons in Os Draconis,but Os Draconis still largely retains the structural features of mammalian bone.Methods:Using verified authentic Os Draconis samples over 10,000 years old as a baseline,this study summarizes the ultrastructural characteristics of genuine Os Draconis.Employing electron probe microanalysis and optical polarized light microscopy,we examined 28 batches of authentic Os Draconis and 31 batches of counterfeits to identify their ultrastructural differences.Key points for ultrastructural identification of Os Draconis were compiled,and a new identification approach was proposed based on these differences.Results:Authentic Os Draconis exhibited distinct ultrastructural markers:irregularly shaped osteons with traversing fissures,deformed/displaced Haversian canals,and secondary mineral infill(predominantly calcium carbonate).Counterfeits showed regular osteon arrangements,absent traversal fissures,and homogeneous hydroxyapatite composition.Lab-simulated samples lacked structural degradation features.EPMA confirmed calcium carbonate infill in fossilized Haversian canals,while elemental profiles differentiated lacunae types(void vs.mineral-packed).Conclusion:The study established ultrastructural criteria for authentic Os Draconis identification:osteon deformation,geological fissures penetrating bone units,and heterogenous mineral deposition.These features,unattainable in counterfeits or modern processed bones,provide a cost-effective,accurate identification method.This approach bridges gaps in TCM material standardization and supports quality control for clinical applications. 展开更多
关键词 Os Draconis ULTRASTRUCTURE identification points electron probe polarized light microscope
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A GALLERY OF PEOPLE AND PLACES
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《ChinAfrica》 2026年第1期12-13,共2页
RUSSIA.A 2026-themed light installation illuminates the ice rink in Gorky Central Park of Culture and Leisure in Moscow on 1 December 2025.
关键词 MOSCOW ILLUMINATION gorky central park culture leisure THEME light installation ice rink
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Bioinspired Precision Peeling of Ultrathin Bamboo Green Cellulose Frameworks for Light Management in Optoelectronics
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作者 Yan Wang Yuan Zhang +2 位作者 Yingfeng Zuo Dawei Zhao Yiqiang Wu 《Nano-Micro Letters》 2026年第1期474-489,共16页
Cellulose frameworks have emerged as promising materials for light management due to their exceptional light-scattering capabilities and sustainable nature.Conventional biomass-derived cellulose frameworks face a fund... Cellulose frameworks have emerged as promising materials for light management due to their exceptional light-scattering capabilities and sustainable nature.Conventional biomass-derived cellulose frameworks face a fundamental trade-off between haze and transparency,coupled with impractical thicknesses(≥1 mm).Inspired by squid’s skin-peeling mechanism,this work develops a peroxyformic acid(HCOOOH)-enabled precision peeling strategy to isolate intact 10-μm-thick bamboo green(BG)frameworks—100×thinner than wood-based counterparts while achieving an unprecedented optical performance(88%haze with 80%transparency).This performance surpasses delignified biomass(transparency<40%at 1 mm)and matches engineered cellulose composites,yet requires no energy-intensive nanofibrillation.The preserved native cellulose I crystalline structure(64.76%crystallinity)and wax-coated uniaxial fibril alignment(Hermans factor:0.23)contribute to high mechanical strength(903 MPa modulus)and broadband light scattering.As a light-management layer in polycrystalline silicon solar cells,the BG framework boosts photoelectric conversion efficiency by 0.41%absolute(18.74%→19.15%),outperforming synthetic anti-reflective coatings.The work establishes a scalable,waste-to-wealth route for optical-grade cellulose materials in next-generation optoelectronics. 展开更多
关键词 Bamboo green Cellulose framework Chemical peeling Optical properties Light management
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Direct Generation of an Array with 78400 Optical Tweezers Using a Single Metasurface
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作者 Yuqing Wang Yuxuan Liao +9 位作者 Tao Zhang Ye Tian Yujia Wu Wenjun Zhang Wei Zhang Yidong Huang Hui Zhai Wenlan Chen Xue Feng Zhongchi Zhang 《Chinese Physics Letters》 2026年第1期129-133,共5页
Scalability remains a major challenge in building practical fault-tolerant quantum computers.Currently,the largest number of qubits achieved across leading quantum platforms ranges from hundreds to thousands.In atom a... Scalability remains a major challenge in building practical fault-tolerant quantum computers.Currently,the largest number of qubits achieved across leading quantum platforms ranges from hundreds to thousands.In atom arrays,scalability is primarily constrained by the capacity to generate large numbers of optical tweezers,and conventional techniques using acousto-optic deflectors or spatial light modulators struggle to produce arrays much beyond∼10,000 tweezers.Moreover,these methods require additional microscope objectives to focus the light into micrometer-sized spots,which further complicates system integration and scalability.Here,we demonstrate the experimental generation of an optical tweezer array containing 280×280 spots using a metasurface,nearly an order of magnitude more than most existing systems.The metasurface leverages a large number of subwavelength phase-control pixels to engineer the wavefront of the incident light,enabling both large-scale tweezer generation and direct focusing into micron-scale spots without the need for a microscope.This result shifts the scalability bottleneck for atom arrays from the tweezer generation hardware to the available laser power.Furthermore,the array shows excellent intensity uniformity exceeding 90%,making it suitable for homogeneous single-atom loading and paving the way for trapping arrays of more than 10,000 atoms in the near future. 展开更多
关键词 quantum computing optical tweezersand quantum platforms optical tweezers atom arraysscalability atom arrays SCALABILITY spatial light modulators
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Pharmacological and light-driven pupillary accommodation in guinea pigs:comparative effects of muscarinic modulators and illumination across developmental stages
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作者 Hao Wu Na Lu +5 位作者 Zhong-Bao Qiao Chi Cheng Wen-Ting Luo Ting Wan Tong Qiao Yue Di 《International Journal of Ophthalmology(English edition)》 2026年第2期211-218,共8页
AIM:To investigate the effects of different light intensities and various mydriatic and miotic drugs on pupil accommodation in guinea pigs.METHODS:Forty-two-week-old guinea pigs were randomly divided into four groups ... AIM:To investigate the effects of different light intensities and various mydriatic and miotic drugs on pupil accommodation in guinea pigs.METHODS:Forty-two-week-old guinea pigs were randomly divided into four groups to assess pupillary responses under varying light intensities(100,250,500 lx)and pharmacological interventions(1%atropine,1%cyclopentolate,1%tropicamide,or 2%pilocarpine).Baseline pupil size and eccentricity were recorded using a non-contact Python-based imaging system integrating edge detection and pixel-to-distance conversion.Direct illumination effects were measured at sequential time points,followed by drug administration and longitudinal tracking of pupillary changes.The protocol was repeated at 12wk of age for developmental comparisons.Postexperiment,enucleated eyes were analyzed to evaluate in vitro vs in vivo differences.RESULTS:Significant age-dependent differences in pupil dynamics were observed.Both 2-and 12-week-old guinea pigs exhibited marked pupil constriction under direct illumination(P<0.001),with decreased eccentricity post-constriction(P<0.001).Indirect illumination caused inconsistent pupil size changes(2-week:P=0.68;12-week:P=0.49).Pharmacologically,atropine,cyclopentolate,and tropicamide induced pupil dilation(P<0.001),whereas pilocarpine caused constriction(P<0.001).All drug groups showed reduced eccentricity(P<0.001).In vivo/in vitro comparisons revealed significant structural differences.CONCLUSION:This study investigates pupillary responses in developing guinea pigs,revealing a direct pupillary light reflex(PLR)with light intensity-dependent responses,while indirect PLR was undetectable.The differential effects of muscarinic modulators on pupillary responses underscore the critical role of cholinergic signaling in ocular accommodation,with age-related variations in sensitivity.Additionally,a novel non-contact measurement methodology achieved a precision of 0.01 mm for pupillary quantification,enhancing accuracy in ocular studies. 展开更多
关键词 PUPIL guinea pig muscarinic receptor modulator light reflex
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Floquet Weyl Semimetals with Linked Fermi Arcs
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作者 Dongling Liu Zheng-Yang Zhuang Zhongbo Yan 《Chinese Physics Letters》 2026年第1期218-224,共7页
Floquet engineering provides a powerful and flexible method for modifying the band structures of quantum materials.While circularly polarized light has been shown to convert curved nodal lines in three-dimensional sem... Floquet engineering provides a powerful and flexible method for modifying the band structures of quantum materials.While circularly polarized light has been shown to convert curved nodal lines in three-dimensional semimetals into Weyl points,such a transformation is forbidden for an isolated straight nodal line.In this work,we uncover a dramatic shift in this paradigm when multiple straight nodal lines intersect.We observe that circularly polarized light not only gaps them into Weyl points but also induces unprecedented surface-state Fermi arcs that extend across the entire surface Brillouin zone and form a linked topological structure.These findings advance our fundamental understanding of light-driven transitions in topological semimetals and unveil a unique Weyl semimetal phase defined by linked Fermi arcs.We discuss potential exotic phenomena arising from this phase,applications of our predictions to spin-split antiferromagnets,and the extension of this Weyl semimetal phase to classical systems. 展开更多
关键词 curved nodal lines weyl points weyl pointssuch floquet engineering quantum materialswhile modifying band structures circularly polarized light Floquet Weyl Semimetals
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Illusion Optics via Phase-Gradient Metasurfaces
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作者 haoyao Pan Jinpeng Yang Yadong Xu 《Chinese Physics Letters》 2026年第1期31-36,共6页
Optical phase-gradient metasurfaces have garnered significant attention for enabling flexible light manipulation,with applications across diverse domains.In this work,we will demonstrate that the metasurfaces with pha... Optical phase-gradient metasurfaces have garnered significant attention for enabling flexible light manipulation,with applications across diverse domains.In this work,we will demonstrate that the metasurfaces with phase gradient modulation can be used to achieve illusion optics,featuring the advantages of simple geometric structure and feasible implementation compared with the well-known transformation optics method.The underlying mechanism is the anomalous diffraction law caused by the phase gradient,which provides a theoretical basis for freely manipulating the propagation path of light.By considering a specific example,we will demonstrate that the phase gradient can transform spatial coordinates in real space into illusion space,thereby converting a plane in real space into a curved surface structure in illusion space to achieve the illusion effect.This approach provides a viable alternative to transformation optics for designing illusion devices. 展开更多
关键词 transformation optics anomalous diffraction law illusion opticsfeaturing flexible light manipulationwith illusion optics anomalous diffraction phase gradient modulation phase gradient metasurfaces
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Supplemental Material for “Floquet Weyl Semimetals with Linked Fermi Arcs”
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作者 Dongling Liu Zheng-Yang Zhuang Zhongbo Yan 《Chinese Physics Letters》 2026年第1期225-230,共6页
This supplemental material contains three sections:(Ⅰ)Derivation of the Floquet lattice Hamiltonian;(Ⅱ)Surface states of the Floquet lattice Hamiltonian;(Ⅲ)Evolution of Floquet Weyl points and Fermi arcs with the i... This supplemental material contains three sections:(Ⅰ)Derivation of the Floquet lattice Hamiltonian;(Ⅱ)Surface states of the Floquet lattice Hamiltonian;(Ⅲ)Evolution of Floquet Weyl points and Fermi arcs with the increase of light amplitude;(Ⅳ)Formalism for light-induced anomalous Hall effects. 展开更多
关键词 Floquet lattice Hamiltonian Light amplitude Anomalous Hall effects Fermi arcs floquet lattice hamiltonian surface Surface states supplemental material Floquet Weyl points
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Gyroid-structured SiOC composite with excellent broadband microwave absorption and load-bearing performance
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作者 Hanjun Wei Siyu Chen +5 位作者 Zhiyong Chen Lu Tang Jimei Xue Cunxian Wang Zhijun Wang Ying Li 《Defence Technology(防务技术)》 2026年第1期277-288,共12页
Designing materials with both structural load-bearing capacity and broadband electromagnetic(EM)wave absorption properties remains a significant challenge.In this work,SiOC/SiC/SiO_(2)composite with gyroid structures ... Designing materials with both structural load-bearing capacity and broadband electromagnetic(EM)wave absorption properties remains a significant challenge.In this work,SiOC/SiC/SiO_(2)composite with gyroid structures were prepared through digital light processing(DLP)3D printing,polymer-derived ceramics(PDCs),chemical vapor infiltration(CVI),and oxidation technologies.The incorporation of the CVISiC phase effectively increases the dissipation capability,while the synergistic interaction between the gyroid structure and SiO_(2)phase significantly improves impedance matching performance.The SiOC/SiC/SiO_(2)composite achieved a minimum reflection loss(RL min)of-62.2 d B at 4.3 mm,and the effective absorption bandwidth(EAB)covered the X-band,with a thickness range of 4.1 mm-4.65 mm.The CST simulation results explain the broadband and low-frequency absorption characteristics,with an EAB of 8.4 GHz(9.6-18 GHz)and an RL min of-21.5 dB at 5 GHz.The excellent EM wave attenuation performance is associated primarily with polarization loss,conduction loss,the gyroid structure's enhancement of multiple reflections and scattering of EM waves,and the resonance effect between the structural units.The SiOC/SiC/SiO_(2)composite also demonstrated strong mechanical properties,with a maximum compressive failure strength of 31.6 MPa in the height direction.This work opens novel prospects for the development of multifunctional structural wave-absorbing materials suitable for broadband microwave absorption and load-bearing properties. 展开更多
关键词 Digital light processing Gyroid structure SiOC/SiC/SiO_(2)composite Microwave absorption Load-bearing properties
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Non-reciprocal Synchronization in Thermal Rydberg Ensembles
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作者 Yunlong Xue Zhengyang Bai 《Chinese Physics Letters》 2026年第1期26-30,共5页
Optical non-reciprocity is a fundamental phenomenon in photonics.It is crucial for developing devices that rely on directional signal control,such as optical isolators and circulators.However,most research in this fie... Optical non-reciprocity is a fundamental phenomenon in photonics.It is crucial for developing devices that rely on directional signal control,such as optical isolators and circulators.However,most research in this field has focused on systems in equilibrium or steady states.In this work,we demonstrate a room-temperature Rydberg atomic platform where the unidirectional propagation of light acts as a switch to mediate time-crystalline-like collective oscillations through atomic synchronization. 展开更多
关键词 atomic synchronization non reciprocal synchronization optical non reciprocity optical isolators thermal Rydberg ensembles directional signal controlsuch time crystalline oscillations unidirectional propagation light
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