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Fully integrated and broadband Si-rich silicon nitride wavelength converter based on Bragg scattering intermodal four-wave mixing

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Photonics Research 2024年第3期12卷 I0001-I0010页

作者： VALERIO VITALI ThALÍA DOMÍNgUEZ BUCIO hAO LIU jOSÉMANUEL LUQUE gONZÁLEZ FRANCISCO jURADO-ROMERO ALEjANDRO ORTEgA-MOÑUX gLENN ChURChILL jAMES C.gATES jAMES hILLIER NIKOLAOS KALFAgIANNIS DANIELE MELATI jENS h.SChMID ILARIA CRISTIANI PAVEL ChEBEN j.gONZALO WANgÜEMERT-PÉREZ ÑIgO MOLINA-FERNÁNDEZ FREDERIC gARDES COSIMO LACAVA PERIKLIS PETROPOULOS Optoelectronics Research Centre University of SouthamptonSouthampton SO171BJUK Electrical Computer and Biomedical Engineering DepartmentUniversity of PaviaPavia 27100Italy Telecommunication Research Institute(TELMA) Universidad de MálagaCEI Andalucı´a TECHE.T.S.I.Telecomunicación29010 MálagaSpain School of Science and Technology Nottingham Trent UniversityNottingham NG118NSUK Department of Electrical Engineering Eindhoven University of TechnologyEindhoven 5600 MBThe Netherlands Department of Materials Science and Engineering University of IoanninaIoannina 45110Greece Centre de Nanosciences et de Nanotechnologies UniversitéParis-SaclayCNRS91120 PalaiseauFrance Advanced Electronics and Photonics Research Center National Research Council CanadaOttawaOntario K1A 0R6Canada

Intermodal four-wave mixing(FWM)processes have recently attracted significant interest for all-optical signal processing applications thanks to the possibility to control the propagation properties of waves exciting distinct spatial modes of the same *** allows,in principle,to place signals in different spectral regions and satisfy the phase matching condition over considerably larger bandwidths compared to intramodal ***,the demonstrations reported so far have shown a limited bandwidth and suffered from the lack of on-chip components designed for broadband manipulation of different *** demonstrate here a silicon-rich silicon nitride wavelength converter based on Bragg scattering intermodal FWM,which integrates mode conversion,multiplexing and de-multiplexing functionalities *** system enables wavelength conversion between pump waves and a signal located in different telecommunication bands(separated by 60 nm)with a 3 dB bandwidth exceeding 70 nm,which represents,to our knowledge,the widest bandwidth ever achieved in an intermodal FWM-based system.

关键词： scattering pump modal

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Empirical model for estimating vertical concentration profiles of re-suspended, sediment-associated contaminants

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Acta Mechanica Sinica 2017年第5期33卷 846-854页

作者： h.W.Zhu P.D.cheng W.Li j.h.chen Y.Pang D.Z.Wang Shanghai Investigation Design & Research Institute Co. Ltd Institute of Environmental Science and Engineering Hohai University Key Laboratory for Mechanics in Fluid Solid Coupling System Institute of Mechanics Chinese Academy of Science Shanghai Institute of Applied Mathematics and Mechanics Shanghai University

Vertical distribution processes of sediment contaminants in water were studied by flume experiments. Experimental results show that settling velocity of sediment particles and turbulence characteristics are the major hydrodynamic factors impacting distribution of pollutants, especially near the bottom where particle diameter is similar in size to vortex structure. Sediment distribution was uniform along the distance, while contaminant distribution slightly lagged behind the sediment. The smaller the initial sediment concentration was, the more time it took to achieve a uniform concentration distribution for suspended sediment. A contaminants transportation equation was established depending on mass conservation equations. Two mathematical estimation models of pollutant distribution in the overlying water considering adsorption and desorption were devised based on vertical distribution of suspended sediment: equilibrium partition model and dynamic micro-diffusion model. The ratio of time scale between the sediment movement and sorption can be used as the index of the models. When this ratio was large, the equilibrium assumption was reasonable, but when it was small, it might require dynamic micro-diffusion model.

关键词： Sediment resuspension Pollutants Concentration distribution Desorption Partition coefficient

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高、低核酸含量原核生物应对资源可利用性降低和原生动物选择性摄食的适应性策略

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中国科学：地球科学 2024年第6期54卷 1901-1913页

作者：胡晨余柳倩陈晓炜刘纪化张瑶 john BATT 肖喜林石蔷张锐骆庭伟焦念志徐大鹏厦门大学环境与生态学院厦门361102 近海海洋环境科学国家重点实验室厦门大学海洋与地球学院福建省海洋碳汇重点实验室厦门361102 joint Lab for Ocean Research and Education(LORE)of Dalhousie University Canadaand Shandong University and Xiamen UniversityXiamen 361102China 香港科技大学(广州)地球与海洋大气科学学域广州510000 山东大学海洋研究院青岛266237 Department of Oceanography Dalhousie UniversityHalifaxNova Scotia B3H 4R2Canada 深圳大学高等研究院深圳518060 厦门大学碳中和创新研究中心厦门361102

原核生物在全球海洋生物地球化学循环中发挥重要作用,然而对它们不同生态亚群(即:高核酸(hNA)和低核酸(LNA)含量亚群)的丰度和代谢活性,以及它们的调控因素如何随着海洋环境条件的变化而变化,仍知之甚少.我们在117,000升的大体积培养体... 详细信息

原核生物在全球海洋生物地球化学循环中发挥重要作用,然而对它们不同生态亚群(即:高核酸(hNA)和低核酸(LNA)含量亚群)的丰度和代谢活性,以及它们的调控因素如何随着海洋环境条件的变化而变化,仍知之甚少.我们在117,000升的大体积培养体系中进行了73天的培养实验,深入研究hNA和LNA亚群对资源可利用性降低和原生动物选择性摄食随时间变化的动态响应.研究结果显示,当培养环境资源充足时, hNA亚群的代谢活性高于LNA亚群,但随着资源日益稀缺, hNA亚群代谢下降速度比LNA亚群快,从而使LNA亚群对原核生物活性的贡献稳步增加.与此同时,随着培养体系资源可利用性逐步降低,原生动物的摄食偏好从hNA亚群转向LNA亚群,使得LNA亚群对培养体系的碳流贡献增加.这些结果突显了LNA亚群在资源有限环境中的韧性,阐明了原生动物选择性摄食在资源条件变化时平衡不同亚群中的关键作用,并展示了在不同环境背景下原生动物和原核生物之间复杂的相互适应性.

关键词：微生物环大体积培养实验原核生物自上而下和自下而上调控作用碳流

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增强乳腺X线摄影在乳腺导管原位癌术前检测中的作用：与低能量成像和MR成像的比较

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国际医学放射学杂志 2024年第4期 498-499页

作者： L.P.Wang P.Wang h.F.Shao j.Li Q.L.Yang 高佳音

摘要目的比较对比增强乳腺X线摄影（CEM）与单独低能量成像（LEI）、CEM与MRI对乳腺导管原位癌（DCIS）的术前诊断价值。方法这项单中心回顾性研究分析了术前2

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Sex-specific facilitation and reproduction of the gynodioecious cushion plant Arenaria polytrichoides on the himalaya-hengduan mountains,SW China

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Plant Diversity 2024年第2期46卷 247-255页

作者： Xufang chen Yazhou Zhang Lishen Qian Renyu Zhou hang Sun jianguo chen State Key Laboratory of Plant Diversity and Specialty Crops Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnanChina Yunnan Key Laboratory of Plateau Wetland Conservation Restoration and Ecological ServicesSouthwest Forestry UniversityKunmingYunnanChina

When benefiting other beneficiaries,cushion plants may reciprocally receive feedback *** feedback effects on different sex morphs,however,remains *** this study,taking the gynodioecious Arenaria polytrichiodes as a model species,we aimed to assess the sex-specific facilitation intensity of cushion plant by measuring the beneficiary cover ratio,and to assess the potential costs in cushion reproductive functions by measuring the flower and fruit cover *** total beneficiary cover ratio was similar between females and *** produced much less flowers but more fruits than *** results suggested that females and hermaphrodites possess similar facilitation intensity,and female cushion *** may allocate more resources saved from pollen production to seed production,while hermaphrodites possibly allocate more resources to pollen production hence reducing seed *** surface areas covered by beneficiaries produced less flowers and fruits than areas without *** addition,strong negative correlations between beneficiary cover and flower cover were detected for both females and hermaphrodites,but the correlation strength were similar for these two sex ***,the correlation between beneficiary cover and fruit cover was only significantly negative for females,suggesting that beneficiary plants negatively affect fruit reproduction of females while have neutral effects on *** the results suggest that to facilitate other beneficiaries can induce reproductive costs on cushion ***,with females possibly suffering greater cost than *** differentiation in reproductive costs between sex morphs,in long-term perspective,may imply sex imbalance in population dynamics.

关键词： Facilitation intensity Feedback effect Sex-specific facilitation Nurse plant Population dynamics Reproductive function

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Study on the preservation effects of the amputated forelimb by machine perfusion at physiological temperature

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Chinese journal of Traumatology 2024年第2期27卷 114-120页

作者： Sheng-Feng chen Bo-Yao Yang Tie-Yuan Zhang Xiang-Yu Song Zhi-Bo jia Lei-jia chen Meng-Yi Cui Wen-jing Xu jiang Peng guizhou Medical University Guiyang550025China Medical School of PLA Beijing100048 China Beijing Key Lab of Regenerative Medicine in Orthopedics Key Laboratory of Musculoskeletal Trauma and War Injuries PLADepartment of OrthopedicsThe Fourth Medical CenterChinese PLA General HospitalBeijing100048China hebei North Universiy Zhangjiakou075000Hebei ProvinceChina

Purpose:Ischemia and hypoxia are the main factors limiting limb replantation and *** cold storage(SCS),a common preservation method for tissues and organs,can only prolong limb ischemia time to 4-6 *** normothermic machine perfusion(NMP)is a promising method for the preservation of tissues and organs,which can extend the preservation time in vitro by providing continuous oxygen and *** study aimed to evaluate the difference in the efficacy of the 2 limb preservation ***:The 6 forelimbs from beagle dogs were divided into 2 *** the SCS group(n=3),the limbs were preserved in a sterile refrigerator at 4°C for 24 h,and in the NMP group(n=3),the perfusate prepared with autologous blood was used for the oxygenated machine perfusion at physiological temperature for 24 h,and the solution was changed every 6 *** effects of limb storage were evaluated by weight gain,perfusate biochemical analysis,enzyme-linked immunosorbent assay,and histological *** statistical analyses and graphs were performed using graphPad Prism 9.0 one-way or two-way analysis of *** p value of less than 0.05 was considered to indicate statistical ***:In the NMP group,the weight gained percentage was 11.72%±4.06%;the hypoxia-inducible factor-1αcontents showed no significant changes;the shape of muscle fibers was normal;the gap between muscle fibers slightly increased,showing the intercellular distance of(30.19±2.83)μm;and the vascularα-smooth muscle actin(α-SMA)contents were lower than those in the normal blood *** creatine kinase level in the perfusate of the NMP group increased from the beginning of perfusion,decreased after each perfusate change,and remained stable at the end of perfusion showing a peak level of 4097.6 U/*** lactate dehydrogenase level of the NMP group increased near the end of perfusion and reached the peak level of 374.4 U/*** the SCS group,the percentage of weight gain was 0.18%±0.10%,a

关键词： Traumatic amputation Machine perfusion Static cold storage Limb replantation

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A hidden precipitation scenario of theθ’-phase in Al-Cu alloys

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journal of Materials Science & Technology 2021年第16期75卷 126-138页

作者： L.Zhou C.L.Wu P.Xie F.j.Niu W.Q.Ming K.Du j.h.chen center for high-resolution electron microscopy college of materials science and engineeringhunan universitychangshahunan410082china shenyang national laboratory for materials science institute of metal researchchinese academy of sciences.shenyan7.110016china

Al-Cu binary alloys are important and interesting industry *** to date,the formation mechanisms of the key strengthening precipitates,namedθ’-phase,in the alloys are still ***,we report that for non-deformed bulk Al-Cu alloys theθ’-phase actually has its own direct precursors that can form only at elevated aging temperature(>ca.200℃).These high-temperature precursors have the same plate-like morphology as theθ’-phase precipitates but rather different *** imaging reveals that they have a tetragonal structure with a=0.405 nm and c=1.213 nm,and an average composition of Al_(5-x)Cu_(1+x)(0≤xg fully coherent with the *** precursor phase may initiate with a composition of Al5 Cu and evolve locally towards Al_(4)Cu_(2)in composition,eventually leading to a consequent structural transformation into theθ’-phase(Al4 Cu2=Al2 Cu).There are evidences that because of their genetic links in structure,such a high-temperature precursor may transform to theθ’-phase without having to change their morphology and interface *** study reveals a well-defined and previously hidden precipitation scenario for theθ’-phase to form in Al-Cu alloys at an elevated aging temperature.

关键词： AlCu alloy Age-hardening Precipitation Electron microscopy

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Nano-phase transformation of composite precipitates in multicomponent Al-Mg-Si(-Sc)alloys

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journal of Materials Science & Technology 2022年第15期110卷 216-226页

作者： S.B.Wang C.F.Pan B.Wei X.Zheng Y.X.Lai j.h.chen Key Laboratory of LCR Materials and Devices of Yunnan Province National Center for International Research on Photoelectric and Energy MaterialsSchool of Materials and EnergyYunnan UniversityKunming 650091China Collaborative Innovation Center of Renewable Energy Materials and Department of Physics Guangxi UniversityNanning 530004China Center for high-Resolution Electron Microscopy College of Materials Science and EngineeringHunan UniversityChangsha 410082China

Sc-addition can significantly enhance the performance of the micro-alloyed Al-Mg-Si-Sc ***,the mechanisms by which the Sc element modifies the microstructure of the alloys are still unknown in many ***,using atomic-scale transmission electron microscopy and atomic-resolution spectroscopy,we have revealed the microstructural differences between two age-hardened Al-0.5Mg-0.4Si(wt.%)alloys with and without *** first significant effect of Sc-addition on the precipitation microstructure of the Al-Mg-Si-Sc alloy is that Sc-atoms may distribute at theβ"-precipitate/Al-matrix interface and therefore accelerate aging kinetics at the initial stage of *** second significant effect of Sc-addition is that in the transition from theβ"-hardened peak-age stage to theβ′-hardened late stage,Sc-atoms can greatly improve the stability of transitionalβ"/B'/β′composite precipitates by entering the B'-substructures and/or locating at the precipitate/Al *** such Sc-atoms effectively suppressβ"toβ'transformation and cross-sectional coarsening of bothβ"and composite precipitates,leading to much finer precipitate needles with smaller diameter but much larger length,as compared with those precipitate needles formed in the alloy without ***,the alloy with Sc-addition exhibits a much better thermal stability than that without Sc.

关键词： Al alloy Strengthening mechanism Phase transition Transmission electron microscopy

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配合间隙对直线共轭内啮合齿轮泵流场特性的影响

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农业机械学报 2024年第2期55卷 442-449页

作者：陈鼎张杨叶绍干盛精厦门理工学院机械与汽车工程学院厦门361024 厦门大学萨本栋微米纳米科学技术研究院厦门361021

直线共轭内啮合齿轮泵是液压系统中的关键组件,因其高效的压力输送特性而广泛应用于工程领域。本文采用计算流体动力学模拟方法对直线共轭内啮合齿轮泵进行研究,分析轴向间隙和径向间隙对齿轮泵泄漏和流场的影响。研究结果表明:配合间... 详细信息

直线共轭内啮合齿轮泵是液压系统中的关键组件,因其高效的压力输送特性而广泛应用于工程领域。本文采用计算流体动力学模拟方法对直线共轭内啮合齿轮泵进行研究,分析轴向间隙和径向间隙对齿轮泵泄漏和流场的影响。研究结果表明:配合间隙的变化对齿轮泵的流场特性产生广泛影响,轴向间隙是引发泄漏的主要因素,约占总泄漏量的80%;当轴向间隙由0.03 mm增加到0.07 mm后,输出流量减少20.81%,平均压力下降33.15%,空化产生的气体体积分数增加0.021;而设置相同径向间隙后,输出流量仅下降0.69%,平均压力下降2.76%,空化产生的气体体积分数增加0.005。此外,导致泵内流速变化的主要配合间隙是轴向间隙,适当减小轴向间隙可提升泵内的流体速度,从而提升泵的整体效率。

关键词：直线共轭内啮合齿轮泵泄漏流场特性配合间隙

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Electron tomography for sintered ceramic materials by a neural network algebraic reconstruction technique

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journal of Materials Science & Technology 2022年第5期100卷 75-81页

作者： R.h.Shen Y.T.he W.Q.Ming Y.Zhang X.D.Xu j.h.chen Centre for high Resolution Electron Microscopy College of Materials Science and EngineeringHunan UniversityChangsha 410082China

The missing wedge effect in electron tomography introduces various types of artifacts in the tomograms and lowers the reconstruction resolution and *** artifacts produced in tomographic reconstruction of bulk materials can be very severe,particularly for sintered bulk ceramic materials in which there are often nano-pores or pore-like microstructure ***,we report a neural network algebraic reconstruction algorithm with no prior knowledge to perform electron tomography for a sintered SiC material with nano carbon *** results show that the proposed algorithm has a great suppressive effect on the missing wedge artifacts and a high tolerance for *** information in the missing wedge can be partly recovered by this ***,both the shape of the bulk SiC specimen and its irregular inner pore-like features are correctly retrieved in the obtained 3D *** study shows the effectiveness of the neural network algorithm for improving the reconstruction accuracy of electron tomography,in order to reveal sophisticated 3D microstructures generally existing in sintered ceramic materials.

关键词： Neural network Missing wedge Electron tomography Sintered ceramics

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