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Nano Research 2024年第3期17卷 1281-1287页

作者： Jiejie Ping Danyang He Fei Wang Nan Wang yi-cheng Fu Zihao Xing Zhiyu Jia Guo-Yu yang Key Laboratory of Cluster Science Ministry of EducationSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China Key Laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education Facluty of Chmeistry Northeast Normal UniversityChangchun 130024China Peking University Third Hospital Beijing 100190China

Polyoxometalate-based nanocomposites with electrocatalytic activity have been applied in hydrogen evolution reactions(HER).Seawater as the main water resource on the earth should be developed as the water electrolysis to prepare high-purity *** this paper,we used two synthesis strategies to prepare the nanocomposite Co_(4)-POM@Co-PGDY(Co_(4)-POM:the Kegging-type microcrystals of K_(10)[Co_(4)(PW_(9)O_(3)4)2]and Co-PGDY:cobalt-porphyrin linked graphdiyne)with excellent activity for ***-PGDY as the porous material is applied not only as the protection of microcrystals towards the metal ion in seawater but also as the co-electrocatalyst of Co_(4)-***_(4)-POM@Co-PGDY exhibits excellent HER performance in seawater electrolytes with low overpotential and high stability at high ***,we have observed a key H_(3)O+intermediate emergence on the surface of nanocomposite during hydrogen evolution process in seawater by Raman synchrotron radiation-based Fourier transform infrared(SR-FTIR).The results in this paper provide an effective strategy for preparing polyoxometalate-based electrocatalysts with high-performance toward hydrogen evolution reaction.

关键词： polyoxometalate graphdiyne seawater hydrogen evolution reaction

A Combined Smoothing Method of Ensemble Pulsar Timescale and Application for Pulsar Atomic Clock Combined Timescale

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Research in Astronomy and Astrophysics 2025年第2期25卷 82-94页

作者： Tinggao yang Minglei Tong Bian Li Zhehao Zhang Xingzhi Zhu Yuping Gao National Time Service Center Chinese Academy of Sciences Key Laboratory of Time and Frequency Primary Standards Chinese Academy of Sciences University of Chinese Academy of Sciences

Clock difference between the ensemble pulsar timescale(PT) and the International Atomic Time(TAI) PT-TAI derived from the International Pulsar Timing Array(IPTA) data set indicates a very similar variation trend with the Terrestrial Time TT(BIPMXXXX)-TAI but PT has larger measurement error. In this paper, we discuss the smoothing method of PT using a combined smoothing filter and compare the results with that from other *** clock difference sequence between PT-TAI and the first time derivative series of the TT(BIPMXXXX)-TAI can be combined by a combined smoothing filter to yield two smooth curves tied by the constraints assuring that the latter is the derivative of the former. The ensemble pulsar time IPTA2016 with respect to TAI published by G. Hobbs et al. and first time derivative series of the TT(BIPM2017)-TAI with quadratic polynomial terms removed are processed by combined smoothing filter in order to demonstrate the properties of the smoothed results. How to correctly estimate two smoothing coefficients is described and the output results of the combined smoothing filter are analyzed. The results show that the combined smoothing method efficiently removes high frequency noises of two input data series and the smoothed data of the PT-TAI combine long term fractional frequency stability of the pulsar time and frequency accuracy of the terrestrial time. Fractional frequency stability analysis indicates that both short and medium time interval stability of the smoothed PT-TAI is improved while keeping its original long term frequency stability level. The combined smoothing filter is more suitable for smoothing observational pulsar timescale data than any filter that only performs smoothing of a single pulsar time series. The smoothed pulsar time by combined smoothing filter is a pulsar atomic time combined timescale. This kind of combined timescale can also be used as terrestrial time.

关键词： (stars:) pulsars: general methods: data analysis time

Influence of Ag doping on the microstructure and electrical properties of ZnO-Bi_2O_3-based varistor ceramics

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International Journal of Minerals,Metallurgy and Materials 2011年第5期18卷 600-605页

作者： Long-Biao Zhu Da-yang Chen Xin-xin Wu Qing-dong Zhong Yu-fa Qi Li-yi Shi Mechanical Engineering College Nantong University Nantong 226007 China Key Laboratory of Modem Metallurgy and Material Processing Shanghai 200072 China Research Center of Nano Science and Technology Shanghai 200444 China

Silver in the form of AgNO3 was added to ZnO-based varistor ceramics prepared by the solid-state reaction *** effects of AgNO3 on both the microstructure and electrical properties of the varistors were studied in *** optimum addition amount of AgNO3 in ZnO-based varistors was also *** mechanism for grain growth inhibition by silver doping was also *** results indicate that the varistor threshold voltage increases substantially along with the AgNO3 content increasing from 0 to 1.5mol%.Also,the introduction of AgNO3 can depress the mean grain size of ZnO,which is mainly responsible for the threshold ***,the addition of AgNO3 results in a slight decrease of donor density and a more severe fall in the density of interface states,which cause a decline in barrier height and an increase in the depletion layer.

关键词： ceramic materials varistors silver microstructure electrical properties zinc oxide

柑橘黄龙病菌在三红蜜柚发病早期对果实品质影响的定量分析

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植物检疫 2025年第1期39卷 8-11页

作者：杨毅弓德强李敏孙进华胡美姣中国热带农业科学院环境与植物保护研究所海南海口571101

柑橘黄龙病是危害橘、橙、柚、柠檬等柑橘类水果的主要病害。与橘、橙相比,柚感染黄龙病后发病慢、症状轻。生产中蜜柚轻病树带病产果现象普遍。为明确黄龙病感染早期对蜜柚果实品质的影响,本研究在黄龙病轻病园中,对三红蜜柚果实品质... 详细信息

柑橘黄龙病是危害橘、橙、柚、柠檬等柑橘类水果的主要病害。与橘、橙相比,柚感染黄龙病后发病慢、症状轻。生产中蜜柚轻病树带病产果现象普遍。为明确黄龙病感染早期对蜜柚果实品质的影响,本研究在黄龙病轻病园中,对三红蜜柚果实品质与柑橘黄龙病菌含量做了定量分析。研究发现,蜜柚感染黄龙病早期,柑橘黄龙病菌含量在0至2^(14)范围内,果实外在品质的主要指标全果重、果形指数、果皮率都没有显著差异;果实内在品质可食率、可溶性固形物和固酸比下降,可滴定酸升高,变化差异都达到显著(P<0.05)或极显著的水平(P<0.01)。实验结果表明,柑橘黄龙病感染早期对三红蜜柚果重、果皮率等外在品质影响轻微,对三红蜜柚果实可溶性固形物等内在品质影响严重。生产上应重视柑橘黄龙病对蜜柚果实品质下降的影响。

关键词：柑橘黄龙病三红蜜柚果实品质

Changes in sensorimotor regions of the cerebral cortex in congenital amusia:a case-control study

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Neural Regeneration Research 2021年第3期16卷 531-536页

作者： Jun-Jie Sun Xue-Qun Pan Ru yang Zhi-Shuai Jin yi-Hui Li Jun Liu Da-Xing Wu Department of Radiology the Second Xiangya Hospital of Central South UniversityChangshaHunan ProvinceChina Department of Radiology the Affiliated Zhuzhou Hospital of Xiangya College of MedicineCentral South UniversityZhuzhouHunan ProvinceChina Lister Hill National Center for Biomedical Communication National Library of MedicineBethesdaMDUSA Medical Psychological Center the Second Xiangya Hospital of Central South UniversityChangshaHunan ProvinceChina

Perceiving pitch is a central function of the human auditory system;congenital amusia is a disorder of pitch *** underlying neural mechanisms of congenital amusia have been actively ***,little attention has been paid to the changes in the motor rain within congenital *** this case-control study,17 participants with congenital amusia and 14 healthy controls underwent functional magnetic resonance imaging while resting with their eyes closed.A voxel-based degree centrality method was used to identify abnormal functional network centrality by comparing degree centrality values between the congenital amusia group and the healthy control *** found decreased degree centrality values in the right primary sensorimotor areas in participants with congenital amusia relative to controls,indicating potentially decreased centrality of the corresponding brain regions in the auditory-sensory motor feedback *** found a significant positive correlation between the degree centrality values and the Montreal Battery of Evaluation of Amusia *** conclusion,our study identified novel,hitherto undiscussed candidate brain regions that may partly contribute to or be modulated by congenital *** evidence supports the view that sensorimotor coupling plays an important role in memory and musical *** study was approved by the Ethics Committee of the Second Xiangya Hospital,Central South University,China(***20180101GZ01)on February 9,2019.

关键词： congenital amusia degree centrality lifelong impairment local functional connectivity music discrimination primary motor area primary sensorimotor area primary sensory area resting-state functional magnetic resonance imaging voxel-based analysis

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基于机器学习方法的员工安全帽佩戴检测

信息技术与信息化 2025年第1期 98-101页

作者：张硕羲任佳亮陈峰曹存盼易杨中油(长汀)催化剂有限公司福建龙岩361000 中国石油兰州石化公司甘肃兰州730000

针对当前化工行业中员工安全帽佩戴检测方法效率低、实时性差等问题,为减少员工由于未佩戴安全帽进入生产装置而发生意外情况,提高安全生产效率,文章提出了一种基于改进YOLOv5算法的员工安全帽佩戴检测方法。首先,采用多尺度Retinex(MSR... 详细信息

针对当前化工行业中员工安全帽佩戴检测方法效率低、实时性差等问题,为减少员工由于未佩戴安全帽进入生产装置而发生意外情况,提高安全生产效率,文章提出了一种基于改进YOLOv5算法的员工安全帽佩戴检测方法。首先,采用多尺度Retinex(MSR)图像处理算法对生产现场视频图像进行预处理,提高视频图像的信噪比,降低噪声干扰;其次,结合SKNet动态注意力机制对原YOLOv5算法模型进行改进,提高视频特征信息提取能力,优化算法的检测精度;最后,对改进的Im-YOLOv5模型的检测准确率进行实验验证。实验结果表明,改进的Im-YOLOv5模型的mAP(mean average precision)达到了93.5%,其准确率相较于YOLOv5得到了提升,具有较好的检测效果。

关键词： Retinex(MSR) 预处理信噪比动态注意力机制 Im-YOLOv5

基于曲线拟合的TEC冷热端温度快速估计方法

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科学技术创新 2025年第5期 22-26页

作者：杨毅胡怡萱罗树钰应展烽祖玮南京理工大学能源与动力工程学院江苏南京

文章基于曲线拟合和重要特征参数辨识方法,提出了一种热电制冷器冷热端温度快速估计方法。研究首先开展了热电制冷器对不同功率下的陶瓷片制冷实验,采集热电制冷器冷热端温度变化曲线。其次,利用有理函数逼近方法对冷热端温度曲线进行拟... 详细信息

文章基于曲线拟合和重要特征参数辨识方法,提出了一种热电制冷器冷热端温度快速估计方法。研究首先开展了热电制冷器对不同功率下的陶瓷片制冷实验,采集热电制冷器冷热端温度变化曲线。其次,利用有理函数逼近方法对冷热端温度曲线进行拟合,获得温度的有理Rational拟合函数。最后,以陶瓷片发热功率作为间接特征参数,通过最小二乘法多项式拟合陶瓷片发热功率与拟合参数的关系,构建以陶瓷片发热功率为特征参数的热电制冷器冷热端温度估计模型。

关键词：模型预测曲线拟合热电制冷器

金属卤素钙钛矿CsPbBr3的电声耦合输运特性研究

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原子与分子物理学报 2025年第2期42卷 169-174页

作者：杨帆周贤中广东工业大学集成电路学院广州510006

金属卤素钙钛矿CsPbBr_(3)在发光方面(Light emitter)的优良表现吸引了许多人把它作为下一代发光、显示与量子信息的可选材料,但其关键的漂移迁移率会受到声子限制.本文将以第一性原理计算得到CsPbBr_(3)的包括极性光学声子(Polar optic... 详细信息

金属卤素钙钛矿CsPbBr_(3)在发光方面(Light emitter)的优良表现吸引了许多人把它作为下一代发光、显示与量子信息的可选材料,但其关键的漂移迁移率会受到声子限制.本文将以第一性原理计算得到CsPbBr_(3)的包括极性光学声子(Polar optical phonon)在内的电声耦合特性,然后使用线性玻尔兹曼方程给出在电场下的解,从而得出漂移迁移率.在论文详述中会给出CsPbBr_(3)的各向异性载流子输运特性的研究,为金属卤素钙钛矿的应用提供一些必要信息.

关键词：第一性原理计算电子-声子耦合漂移迁移率

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Stereocomplex Crystallization in Asymmetric Diblock Copolymers Studied by Dynamic Monte Carlo Simulations

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Chinese Journal of Polymer Science 2021年第5期39卷 632-639,I0008页

作者： ying Xu Jun yang Zong-Fa Liu Zhi-Ping Zhou Zhao-Peng Liang Tong-Fan Hao yi-Jing Nie Research School of Polymeric Materials School of Materials Science and EngineeringJiangsu UniversityZhenjiang 212013China Institute of Green Chemistry and Chemical Technology Jiangsu UniversityZhenjiang 212013China

Stereocomplex crystallization in asymmetric diblock copolymers was studied using dynamic Monte Carlo simulations,and the key factor dominating the formation of stereocomplex crystallites(SCs)was *** asymmetric diblock copolymers with higher degree of asymmetry exhibit larger difference between volume fractions of beads of different blocks,and local miscibility between different kinds of beads is lower,leading to lower SC *** minimize the interference from volume fraction of beads,the SC formation in blends of asymmetric diblock copolymers was also *** the cases where the volume fractions of beads of different blocks are the same,similar local miscibility between beads of different blocks and similar SC content was *** findings indicate that the volume fraction of beads of different blocks is a key factor controlling the SC formation in the asymmetric diblock *** SC content can be regulated by adjusting the difference between the contents of beads of different blocks in asymmetric diblock copolymers.

关键词： Asymmetric diblock copolymers Monte Carlo simulations Stereocomplex crystallization

Study of the characteristics of rocket-triggered lightning energetic radiation and its relationships with the discharge parameters

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Science China Earth Sciences 2023年第3期66卷 633-647页

作者： Xiong ZHANG Xiaoqiang LI yang ZHANG Baofeng CAO yi ZHENG Rubin JIANG Peng LI Hongbo ZHANG Weitao LYU State Key Laboratory of NBC Protection for Civilian Beijing 102205China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China

Through the use of the independently developed Thunderstorm Energetic Radiation Observation System(TEROS),observation experiments of rocket-triggered lightning energetic radiation(RLER)were conducted for the first time at the Field Experiment Base on Lightning Sciences,China Meteorological Administration from May 2021 to July 2021.A total of 17 X-ray bursts were detected during all of the 22 leader/return *** this study,the energy,time,and direction characteristics of Xray burst and its relationships with the corresponding discharge parameters,such as the return stroke peak current,half-peak width,rise time,and interstroke time interval,as well as the associated physical processes,are analyzed and *** showed that energetic radiation is ubiquitous in triggered lightning and is closely related to the last downward leader phase before the return *** photon energies were concentrated in tens to hundreds of ke V,and the average duration of RLER was approximately 27μ***,RLER exhibited directional property inconsistent with a vertical downward beam,which may be related to the development orientation of the lightning *** intensity of RLER was positively correlated with the return stroke peak current,indicating that it directly depends on the lightning intensity,but it would be modulated by the lightning channel *** 17 RLER events showed 3 different time distribution patterns,namely,discrete,continuous,and discrete/continuous pulses,of which the discharge parameters were also *** discrete pulse event had the longest duration,a small half-peak width,and a long interstroke time ***,all of these events occurred during the last several leader/return *** continuous pulse event had a short duration and a small peak *** discrete/continuous pulse event had a moderate duration and a large half-peak width and peak *** three distinct time distribution patterns may be determined by

关键词： Rocket-triggered lightning Lightning energetic radiation X-ray burst Channel base current Leader high-field runaway mechanism