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Chinese Journal of Chemical Engineering 2024年第4期68卷 263-275页

作者： Kejin Li jiahui liu Dajian Li Xiaolan Chen Chunhui Zhou Research Group for Advanced Materials&Sustainable Catalysis(AMSC) State Key Laboratory Breeding Base of Green Chemistry-Synthesis TechnologyCollege of Chemical EngineeringZhejiang University of TechnologyHangzhou 310032China Qing Yang Institute for Industrial Minerals Qingyang 242804China Engineering Research Center of Non-metallic Minerals of Zhejiang Province Zhejiang Institute of Geology and Mineral ResourcesHangzhou 310007China

Microreactors are increasingly used for green and safe chemical processes owing to their benefits of superior mass and heat transfer,increased yield,safety,and simplicity of ***,immobilizing catalysts in microreactors remains *** this investigation,a technique for creating Cu_(2)O/montmorillonite catalyst coating,using electrostatic attraction for layer-by-layer self-assembly,was *** montmorillonite film's morphology and thickness could be efficiently regulated by adjusting the degree of exfoliation and surface charge of montmorillonite,alongside layer-by-layer coating *** Cu_(2)O nanoparticles were immobilized using the flow deposition *** resulting Cu_(2)O@montmorillonite-film-coated capillary microreactor successfully transformed glycerol into *** conversion of glycerol and product selectivity could be controlled by adjusting the molar ratio of reactants,temperature,residence time,and Cu_(2)O *** maximum glycerol conversion observed was 47.6%,with a 27%selectivity toward *** study presents a technique for immobilizing montmorillonite-based catalyst coatings in capillary tubing,which can serve as a foundation for the future application of microreactors in glycerol conversion.

关键词： Microreactor Coating Montmorillonite Glycerol Cu_(2)O

A hybrid attention model based on first-order statistical features for smoke recognition

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Science China(Technological Sciences) 2024年第3期67卷 809-822页

作者： GUO Nan liu jiahui DI KeXin GU Ke QIAO JunFei Beijing Laboratory of Smart Environmental Protection Beijing Key Laboratory of Computational Intelligence and Intelligent SystemBeijing Artificial Intelligence InstituteBeijing 100124China Faculty of Information Technology Beijing University of TechnologyBeijing 100124China

Smoke and fire recognition are of great importance on foreseeing fire disasters and preventing environmental pollution by monitoring the burning process of objects(e.g., straw, fuels). However, since fire images suffer from problems like the variability of the features, complexity of scenarios, interference from background, changeable weather conditions as well as image quality problems, identifying smoke and fire accurately and promptly from a given image still remains a substantial challenge. Automatically learning the features of smoke images by CNNs has improved the target recognition ability compared to traditional approaches,nonetheless, convolutions and pooling operations in CNNs may cause severe information loss which may lead to *** tackle the above problems, this paper proposed a hybrid attention model based on the characteristics of smoke images. This model adopted multiple optimized attention mechanism in several stages to quickly and precisely capture the important features,achieving state-of-the-art performance on smoke and fire recognition in terms of accuracy and speed. Our proposed module mainly consists of two stages: pooling and attention. In the first stage, we conducted several newly proposed first-order pooling methods. Through traversing the data space in a larger scope, features are better reserved, thus constructing a more intact feature space of smoke and fire in an image. In the second stage, feature maps are aggregated together to perform channel and spatial attention. The channel and spatial dependencies allow us to quickly catch the important features presented in an image. By fully exploring the feature space and prominent salient features, characteristics of smoke and fire are better presented so as to obtain better smoke and fire detection results. Experiments have been conducted on public smoke detection dataset and new proposed fine-grained smoke and fire detection database. Experimental results revealed that the propose

关键词： hybrid attention first-order pooling smoke and fire detection deep convolutional neural networks

SFGA-CPA: A Novel Screening Correlation Power Analysis Framework Based on Genetic Algorithm

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Computers, Materials & Continua 2024年第6期79卷 4641-4657页

作者： jiahui liu Lang Li Di Li Yu Ou College of Computer Science and Technology Hengyang Normal UniversityHengyang421002China Hunan Provincial Key Laboratory of Intelligent Information Processing and Application Hengyang Normal UniversityHengyang421002China

Correlation power analysis(CPA)combined with genetic algorithms(GA)now achieves greater attack efficiency and can recover all subkeys ***,two issues in GA-based CPA still need to be addressed:key degeneration and slow evolution within *** challenges significantly hinder key recovery *** paper proposes a screening correlation power analysis framework combined with a genetic algorithm,named SFGA-CPA,to address these ***-CPA introduces three operations designed to exploit CPA characteris-tics:propagative operation,constrained crossover,and constrained ***,the propagative operation accelerates population evolution by maximizing the number of correct bytes in each ***,the constrained crossover and mutation operations effectively address key degeneration by preventing the compromise of correct ***,an intelligent search method is proposed to identify optimal parameters,further improving attack *** were conducted on both simulated environments and real power traces collected from the SAKURA-G *** the case of simulation,SFGA-CPA reduces the number of traces by 27.3%and 60%compared to CPA based on multiple screening methods(MS-CPA)and CPA based on simple GA method(SGA-CPA)when the success rate reaches 90%.Moreover,real experimental results on the SAKURA-G platform demonstrate that our approach outperforms other methods.

关键词： Side-channel analysis correlation power analysis genetic algorithm crossover mutation

Significantly enhanced thermal stability of HMX by phase-transition lysozyme coating

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Defence Technology（防务技术） 2024年第5期35卷 60-68页

作者： jiahui liu Congmei Lin Jianhu Zhang Chengcheng Zeng Zhijian Yang Fude Nie Institute of Chemical Materials China Academy of Engineering Physics(CAEP)Mianyang 621900China Graduate School China Academy of Engineering Physics(CAEP)Mianyang 621900China

A new robust bio-inspired route by using lysozyme aqueous solution for surface modification on 1,3,5,7-tetranitro-1,3,5,7-tetrazocane(HMX)was described in this *** crystals were coated by in situ phase transition of lysozyme(PTL)*** HMX decorated by PTL was characterized by SEM,XRD,FTIR and XPS,demonstrating a dense core-shell coating *** coverage of lysozyme on HMX crystal was calculated by the ratio of sulfur *** surface coverage increased from 60.5% to 93.5% when the content of PTL was changed from 0.5 wt% to 2.0 wt%,indicating efficient *** thermal stability of HMX was investigated by in situ XRD and *** thermal phase transition temperature of HMX(β to δ phase)was delayed by 42℃ with 2.0 wt% PTL coating,which prevented HMX from thermal damage and sensitivity by the effect of PTL *** heating at 215℃,large cracks appeared in the naked HMX crystal,while the PTL coated HMX still maintained intact,with the impact energy of HMX dropped dramatically from 5 J to 2 ***,the impact energy of HMX with 1.0 wt% and 2.0 wt% coating content(HMX@PTL-1.0 and HMX@PTL-2.0)was unchanged(5 J).Present results potentially enable large-scale fabrication of polymorphic energetic materials with outstanding thermal stability by novel lysozyme coating.

关键词： HMX Lysozyme Phase transition Thermal stability Sensitivity

A bulk extraction method to determine the stable isotope ratios of iron,nickel,copper,zinc,and cadmium in seawater using multi-collector inductively coupled plasma mass spectrometry

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Acta Oceanologica Sinica 2024年第7期43卷 125-137页

作者： Zhan Shen Yuncong Ge jiahui liu Wenkai Guan Wenfeng Hu Ruifeng Zhang School of Oceanography Shanghai Jiao Tong UniversityShanghai 200030China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519015China Shanghai Key Laboratory of Polar Life and Environment Sciences Shanghai Jiao Tong UniversityShanghai 200030China Key Laboratory of Polar Ecosystem and Climate Change of Ministry of Education Shanghai Jiao Tong UniversityShanghai 200030China Laboratory for Polar Science Polar Research Institute of ChinaMinistry of Natural ResourcesShanghai 200136China

The oceanic trace metals iron(Fe),nickel(Ni),copper(Cu),zinc(Zn),and cadmium(Cd)are crucial to marine phytoplankton growth and global carbon cycle,and the analysis of their stable isotopes can provide valuable insights into their biogeochemical cycles within the ***,the simultaneous isotopic analysis of multiple elements present in seawater is challenging because of their low concentrations,limited volumes of the test samples,and high salt *** this study,we present the novel method developed for the simultaneous analysis of five isotope systems by 1 L seawater *** the developed method,the NOBIAS Chelate-PA1 resin was used to extract metals from seawater,the AG MP-1M anion-exchange resin to purify Cu,Fe,Zn,Cd,and the NOBIAS Chelate-PA1 resin to further extract Ni from the matrix ***,a multi-collector inductively coupled plasma mass spectroscope(MC-ICPMS)was employed for the isotopic measurements using a doublespike technique or sample-standard bracketing combined with internal *** method exhibited low total procedural blanks(0.04 pg,0.04 pg,0.21 pg,0.15 pg,and 3 pg for Ni,Cu,Fe,Zn,and Cd,respectively)and high extraction efficiencies(100.5%±0.3%,100.2%±0.5%,97.8%±1.4%,99.9%±0.8%,and 100.1%±0.2%for Ni,Cu,Fe,Zn,and Cd,respectively).The external errors and external precisions of this method could be considered *** proposed method was further tested on the seawater samples obtained from the whole vertical profile of a water column during the Chinese GEOTRACES GP09 cruise in the Northwest Pacific,and the results showed good agreement with previous related *** innovative method will contribute to the advancement of isotope research and enhance our understanding of the marine biogeochemical cycling of Fe,Ni,Cu,Zn,and Cd.

关键词： trace metal stable isotopes seawater bulk extraction

Enhanced Electrical Properties of Bi2-xSbxTe3 Nanoflake Thin Films Through Interface Engineering

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ENERGY & ENVIRONMENTAL MATERIALS 2024年第6期7卷 359-366页

作者： Wu, Xudong Ding, Junjie Cui, Wenjun Lin, Weixiao Xue, Zefan Yang, Zhi liu, jiahui Nie, Xiaolei Zhu, Wanting Van Tendeloo, Gustaaf Sang, Xiahan Wuhan Univ Technol State Key Lab Adv Technol Mat Synth & Proc Wuhan 430070 Peoples R China Wuhan Univ Technol NRC Nanostruct Res Ctr Wuhan 430070 Peoples R China Univ Antwerp EMAT Electron Microscopy Mat Sci Groenenborgerlaan 171 B-2023 Antwerp Belgium

The structure-property relationship at interfaces is difficult to probe for thermoelectric materials with a complex interfacial microstructure. Designing thermoelectric materials with a simple, structurally-uniform interface provides a facile way to understand how these interfaces influence the transport properties. Here, we synthesized Bi2-xSbxTe3 (x = 0, 0.1, 0.2, 0.4) nanoflakes using a hydrothermal method, and prepared Bi2-xSbxTe3 thin films with predominantly (0001) interfaces by stacking the nanoflakes through spin coating. The influence of the annealing temperature and Sb content on the (0001) interface structure was systematically investigated at atomic scale using aberration-corrected scanning transmission electron microscopy. Annealing and Sb doping facilitate atom diffusion and migration between adjacent nanoflakes along the (0001) interface. As such it enhances interfacial connectivity and improves the electrical transport properties. Interfac reactions create new interfaces that increase the scattering and the Seebeck coefficient. Due to the simultaneous optimization of electrical conductivity and Seebeck coefficient, the maximum power factor of the Bi1.8Sb0.2Te3 nanoflake films reaches 1.72 mW m(-1) K-2, which is 43% higher than that of a pure Bi2Te3 thin film.

关键词： Bi2Te3 nanoflakes interface engineering scanning transmission electron microscopy thermoelectric thin film HIGH-THERMOELECTRIC PERFORMANCE POWER-GENERATION 2D MATERIALS GROWTH BISMUTH TELLURIDE NANOPLATELETS MECHANISMS NANOSHEETS MAGNETISM

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灌区对塔里木盆地西部极端暴雨的影响

清华大学学报（自然科学版） 2024年第2期64卷 259-270页

作者：刘家辉倪广恒清华大学土木水利学院水沙科学与水利水电工程国家重点实验室北京100084

塔里木盆地灌区支撑着当地的经济和社会发展,而近年来盆地内部的暴雨事件严重威胁人民群众的生命财产安全。该文通过中尺度气象模式(WRF)设置有无灌区的对比模拟实验,以2021年6月15日盆地西部的暴雨(“6·15”暴雨)为例,发现灌区使暴雨... 详细信息

塔里木盆地灌区支撑着当地的经济和社会发展,而近年来盆地内部的暴雨事件严重威胁人民群众的生命财产安全。该文通过中尺度气象模式(WRF)设置有无灌区的对比模拟实验,以2021年6月15日盆地西部的暴雨(“6·15”暴雨)为例,发现灌区使暴雨强度增加,并揭示了灌区对暴雨水汽输送过程和暴雨形成的影响机制。结果表明:由偏东急流引起的大量水汽向盆地西部输送是“6·15”暴雨形成的主要原因;灌区对水汽输送的阻挡作用使输送区域至暴雨区域的水汽增加,且灌区和山区地形的共同影响使水汽抬升作用增强,导致更多水汽在暴雨落区集中,使暴雨雨量增加。

关键词：塔里木盆地灌区极端暴雨水汽输送

信控交叉口公交专用车道动态共享实时控制方法

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哈尔滨工业大学学报 2024年第3期56卷 98-109页

作者：刘嘉晖陈科陈群中南大学交通运输工程学院长沙410075 湖南省交通规划勘察设计院有限公司长沙410200

针对目前交叉口拥堵、公交专用车道利用率低的问题,提出一种信控交叉口公交专用车道动态共享实时控制方法。利用GPS定位实时获取交叉口处公交车的位置,并通过交通检测设备获取专用道内小汽车车辆数,结合主信号显示情况综合计算当前时刻... 详细信息

针对目前交叉口拥堵、公交专用车道利用率低的问题,提出一种信控交叉口公交专用车道动态共享实时控制方法。利用GPS定位实时获取交叉口处公交车的位置,并通过交通检测设备获取专用道内小汽车车辆数,结合主信号显示情况综合计算当前时刻公交专用道共享前后交叉口车辆总延误。将延误大小判断结果反馈给车道信号,车道信号显示红灯或绿灯以提醒司机是否能够进入公交专用道。引入受影响车辆概念,建立以减少交叉口车辆总延误为目标的公交专用车道共享控制模型。通过对当前时刻主信号显示红灯和显示绿灯两种情况分析,提出一种综合考虑车辆司乘系数、受影响车辆的交叉口延误计算方法,得到共享公交专用车道前后交叉口车辆总延误差值的表达式。利用示例数值模拟在多种不同场景下车道信号的显示情况,分析了专用道内已有车辆、公交车位置以及主信号显示情况对车道共享的影响。结果表明:该控制方法较符合实际情况,并能有效提高公交专用车道利用率,能够充分利用交叉口绿灯时间,为解决公交专用车道的动态共享、缓解道路拥堵提供了一种新的思路。

关键词：交通运输工程车道共享方案建模仿真公交专用车道 GPS观测交叉口延误

Programmable photonic RF filters based on an integrated Fabry-Pérot laser with a saturable absorber

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Chinese Optics Letters 2024年第2期22卷 214-220页

作者：徐真真刘奕彤刘嘉慧王玲孙文韬孙振兴陈向飞 Key Laboratory of Intelligent Optical Sensing and Manipulation of the Ministry of Education&National Laboratory of Solid State Microstructures&College of Engineering and Applied Sciences&Institute of Optical Communication Engineering&Nanjing University-Tongding Joint Lab for Large-Scale Photonic Integrated Circuits Nanjing UniversityNanjing 210023China

We propose and experimentally demonstrate the programmable photonic radio frequency(RF)filters based on an integrated Fabry-Pérot laser with a saturable absorber(FP-SA).Owing to the high output power and the relative flatness spectrum of the FP-SA laser,only a waveshaper and an erbium-doped fiber amplifier(EDFA)were needed,which can greatly reduce the complexity of the *** sinc filter employed 87 taps,representing a record-high tap number and resulting in a 3-d B bandwidth of 0.27 GHz and a quality factor of ***,Gaussian apodization enabled the out-of-band rejection of the filter to reach 34 d B and the center frequency to be finely tuned over a wide range,spanning from 4 to 14 *** results indicate that the proposed scheme could provide a promising guideline for the photonic RF filters that demand both high reconfigurability and greatly reduced size and complexity.

关键词： microwave filters microwave photonics passively mode-locked laser

B-N covalent bond-involved π-extension of multiple resonance emitters enables high-performance narrowband electroluminescence

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National Science Review 2024年第06期 243-253页

作者： Xingyu Huang jiahui liu Yulin Xu Guohao Chen Manli Huang Mingxin Yu Xialei Lv Xiaojun Yin Yang Zou Jingsheng Miao Xiaosong Cao Chuluo Yang Shenzhen Key Laboratory of New Information Display and Storage Materials College of Materials Science and EngineeringShenzhen University College of Physics and Optoelectronic Engineering Shenzhen University

Multi-boron-embedded multiple resonance thermally activated delayed fluorescence（MR-TADF） emitters show promise for achieving both high color-purity emission and high exciton utilization ***, their development is often impeded by a limited synthetic scope and excessive molecular weights,which challenge material acquisition and organic light-emitting diode（OLED） fabrication by vacuum deposition. Herein, we put forward a B–N covalent bond-involved π-extension strategy via post-functionalization of MR frameworks, leading to the generation of high-order B/N-based motifs. The structurally and electronically extended π-system not only enhances molecular rigidity to narrow emission linewidth but also promotes reverse intersystem crossing to mitigate efficiency roll-off. As illustrated examples, ultra-narrowband sky-blue emitters（full-width at half-maximum as small as 8 nm in n-hexane）have been developed with multi-dimensional improvement in photophysical properties compared to their precursor emitters, which enables narrowband OLEDs with external quantum efficiencies(EQEmax) of up to 42.6%, in company with alleviated efficiency decline at high brightness, representing the best efficiency reported for single-host OLEDs. The success of these emitters highlights the effectiveness of our molecular design strategy for advanced MR-TADF emitters and confirms their extensive potential in high-performance optoelectronic devices.

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