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Advancing large-scale thin-film PPLN nonlinear photonics with segmented tunable micro-heaters

Photonics Research 2024年第8期12卷 1703-1708页

作者： XIAOTING LI HAOCHUAN LI ZHENZHENG WANG ZHAOXI chen FEI MA ke ZHANG WENZHAO SUN chenG WANG Department of Electrical Engineering City University of Hong KongHong KongChina School of Physics Sun Yat-sen UniversityGuangzhou 510275China City University of Hong Kong(Dongguan) Dongguan 523808China Center of Information and Communication Technology City University of Hong Kong Shenzhen Research InstituteShenzhen 518057China State key Laboratory of Terahertz and Millimeter Waves City University of Hong KongHong KongChina

Thin-film periodically poled lithium niobate(TF-PPLN)devices have recently gained prominence for efficient wavelength conversion processes in both classical and quantum ***,the patterning and poling of TF-PPLN devices today are mostly performed at chip scales,presenting a significant bottleneck for future largescale nonlinear photonic systems that require the integration of multiple nonlinear components with consistent performance and low ***,we take a pivotal step towards this goal by developing a wafer-scale TF-PPLN nonlinear photonic platform,leveraging ultraviolet stepper lithography and an automated poling *** address the inhomogeneous broadening of the quasi-phase matching(QPM)spectrum induced by film thickness variations across the wafer,we propose and demonstrate segmented thermal optic tuning modules that can precisely adjust and align the QPM peak wavelengths in each *** the segmented micro-heaters,we show the successful realignment of inhomogeneously broadened multi-peak QPM spectra with up to 57%enhancement of conversion *** achieve a high normalized conversion efficiency of 3802%W-1cm-2in a 6 mm long PPLN waveguide,recovering 84%of the theoretically predicted efficiency in this *** advanced fabrication techniques and segmented tuning architectures presented herein pave the way for wafer-scale integration of complex functional nonlinear photonic circuits with applications in quantum information processing,precision sensing and metrology,and low-noise-figure optical signal amplification.

关键词： tuning tunable waveguide

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Zinc glycine chelate ameliorates DSS‑induced intestinal barrier dysfunction via attenuating TLR4/NF‑κB pathway in meat ducks

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Journal of Animal Science and Biotechnology 2024年第2期15卷 765-778页

作者： Yaqi Chang ke Wang Guangmang Liu Hua Zhao Xiaoling chen jingyi Cai Gang jia Institute of Animal Nutrition Key Laboratory for Animal Disease‑Resistance Nutrition of ChinaMinistry of EducationSichuan Agricultural UniversityChengdu 611130SichuanChina

Background Zinc glycine chelate(Zn-Gly)has anti-inflammation and growth-promoting properties;however,the mechanism of Zn-Gly contribution to gut barrier function in Cherry Valley ducks during intestinal inflammation is ***-hundred 1-day-old ducks were divided into 5 groups(6 replicates and 10 ducks per replicate)in a completely randomized design:the control and dextran sulfate sodium(DSS)groups were fed a corn-soybean meal basal diet,and experimental groups received supplements of 70,120 or 170 mg/kg Zn in form of *** DSS and treatment groups were given 2 mL of 0.45 g/mL DSS daily during d 15–21,and the control group received normal *** experiment lasted 21 *** Compared with DSS group,70,120 and 170 mg/kg Zn significantly increased body weight(BW),villus height and the ratio of villus to crypt,and significantly decreased the crypt depth of jejunum at 21 *** number of goblet cells in jejunal villi in the Zn-Gly group was significantly increased by periodic acid-Schiff *** with control,the content of intestinal permeability marker D-lactic acid(D-LA)and fluxes of fluorescein isothiocyanate(FITC-D)in plasma of DSS group significantly increased,and 170 mg/kg Zn supplementation significantly decreased the D-LA content and FITC-D *** with control,contents of plasma,jejunum endotoxin and jejunum pro-inflammatory factors IL-1β,IL-6 and TNF-αwere significantly increased in DSS group,and were significantly decreased by 170 mg/kg Zn *** Zn significantly increased the contents of anti-inflammatory factors IL-10,IL-22 and sIgA and IgG in ***-time PCR and Western blot results showed that 170 mg/kg Zn supplementation significantly increased mRNA expression levels of CLDN-1 and expression of OCLN protein in jejunum,and decreased gene and protein expression of CLDN-2 compared with DSS *** 120 mg/kg Zn significantly promoted the expressions of IL-22 and *** Zn-Gly supplementation sign

关键词： Cherry Valley ducks Growth performance Gut inflammation Intestinal barrier Zn-Gly

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Ceramic-based meta-material absorber with high-temperature stability

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Rare Metals 2024年第9期43卷 4433-4440页

作者： Xing-Cong chen Wei-jia Luo Run-Ni Zhao Yong-Zheng Wen ji Zhou State key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

With the continuous exploration of uncharted and extreme environments,enhanced temperature robustness of passive devices has become particularly *** this study,a ceramic-based meta-material absorber with exceptional temperature stability is developed using a fusion design approach that combines rare metal-based tungsten bronze structural ceramics and ***,the absorbance of the meta-material array based on Mie resonance exceeds 49.0%in both waveguides and free space,approaching the theoretical *** to impedance analysis,the absorption performance can be distinctly correlated with the dielectric loss(Q_(f)).Notably,the high-temperature robustness is verified to still be effective at 400℃.These advancements in our design allow for the use of monolithic materials in fabricating temperature-stable perfect absorbers,providing greater freedom in the dielectric performance and expanding their potential applications,including in space exploration and 5G millimeter-wave scenarios.

关键词： Temperature robustness Meta-material absorber Microwave absorption Rare metal-based ceramics Miniaturization

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Retrieval of Antarctic sea ice freeboard and thickness from HY-2B satellite altimeter data

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Acta Oceanologica Sinica 2024年第3期43卷 87-101页

作者： Yizhuo chen Xiaoping Pang Qing ji Zhongnan Yan Zeyu Liang chenlei Zhang Chinese Antarctic Center of Surveying and Mapping Wuhan UniversityWuhan 430079China key Laboratory of Polar Surveying and Mapping Science Ministry of Natural ResourcesWuhan 430079China key Laboratory of Polar Environment Monitoring and Public Governance Ministry of EducationWuhan 430079China 4 School of Geography and Tourism Anhui Normal UniversityWuhu 241002China

Antarctic sea ice is an important part of the Earth’s atmospheric system,and satellite remote sensing is an important technology for observing Antarctic sea *** Chinese Haiyang-2B(HY-2B)satellite altimeter data could be used to estimate sea ice freeboard and provide alternative Antarctic sea ice thickness information with a high precision and long time series,as other radar altimetry satellites can,needs further *** paper proposed an algorithm to discriminate leads and then retrieve sea ice freeboard and thickness from HY-2B radar altimeter *** first collected the Moderate-resolution Imaging Spectroradiometer ice surface temperature(IST)product from the National Aeronautics and Space Administration to extract leads from the Antarctic waters and verified their accuracy through Sentinel-1 Synthetic Aperture Radar ***,a surface classification decision tree was generated for HY-2B satellite altimeter measurements of the Antarctic waters to extract leads and calculate local sea surface *** then estimated the Antarctic sea ice freeboard and thickness based on local sea surface heights and the static equilibrium ***,the retrieved HY-2B Antarctic sea ice thickness was compared with the CryoSat-2 sea ice thickness and the Antarctic Sea Ice Processes and Climate(ASPeCt)ship-based observed sea ice *** results indicate that our classification decision tree constructed for HY-2B satellite altimeter measurements was reasonable,and the root mean square error of the obtained sea ice thickness compared to the ship measurements was 0.62 *** proposed sea ice thickness algorithm for the HY-2B radar satellite fills a gap in this application domain for the HY-series satellites and can be a complement to existing Antarctic sea ice thickness products;this algorithm could provide long-time-series and large-scale sea ice thickness data that contribute to research on global climate change.

关键词： HY-2B satellite altimeter classification decision tree sea ice freeboard and thickness Antarctic waters

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Development review and the prospect of oil shale in-situ catalysis conversion technology

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Petroleum Science 2024年第2期21卷 1385-1395页

作者： Li Wang chen-Hao Gao Rui-Ying Xiong Xiao-Jun Zhang ji-Xiang Guo The Unconventional Oil and Gas Institute China University of Petroleum-BeijingBeijing102200China

As an unconventional resource, oil shale possesses abundant reserves and significant potential for industrial applications. The rational and efficient development of oil shale resources holds immense importance in reducing national energy demand. In-situ catalytic technology, characterized by its high efficiency, low pollution, and minimal energy consumption, represents a key direction for future oil shale development. This paper provides a comprehensive review of research progress in in-situ oil shale mining technology, oil shale pyrolysis catalysts, the pyrolysis mechanism of kerogen, and the compatibility of different heating processes and catalysts. Furthermore, the paper proposes future research directions and prospects for oil shale in-situ catalytic technology, including reservoir modification, highefficiency catalyst synthesis, injection processes, and high-efficiency heating technology. These insights serve as valuable technical references for the advancement of oil shale in-situ catalytic technology.

关键词： Oil shale In-situ catalytic technology Pyrolysis catalyst kerogen pyrolysis mechanism

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Fast X-ray imaging beamline at SSRF

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Nuclear Science and Techniques 2024年第9期35卷 68-81页

作者： ke Li Hong-Lan Xie Ya-Nan Fu Fei-Xiang Wang Guo-Hao Du jian-Feng ji Biao Deng Ti-Qiao Xiao Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China

The fast X-ray imaging beamline(BL16U2)at Shanghai Synchrotron Radiation Facility(SSRF)is a new beamline that provides X-ray micro-imaging capabilities across a wide range of time scales,spanning from 100 ps toμs and *** beamline has been specifically designed to facilitate the investigation of a wide range of rapid phenomena,such as the deformation and failure of materials subjected to intense dynamic *** addition,it enables the study of high-pressure and high-speed fuel spray processes in automotive *** light source of this beamline is a cryogenic permanent magnet undulator(CPMU)that is cooled by liquid *** CPMU can generate X-ray photons within an energy range of 8.7-30 *** beamline offers two modes of operation:monochromatic beam mode with a liquid nitrogen-cooled double-crystal monochromator(DCM)and pink beam mode with the first crystal of the DCM out of the beam *** X-ray imaging methods were implemented in BL16U2:single-pulse ultrafast X-ray imaging,microsecond-resolved X-ray dynamic imaging,millisecond-resolved X-ray dynamic micro-CT,and high-resolution quantitative ***,BL16U2 is equipped with various in situ impact loading systems,such as a split Hopkinson bar system,light gas gun,and fuel spray *** the completion of the final commissioning in 2021 and subsequent trial operations in 2022,the beamline has been officially available to users from 2023.

关键词： Multiple time-scale X ray imaging Single-pulse X ray imaging Dynamic 2D imaging Dynamic micro-CT

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Semantic segmentation-based semantic communication system for image transmission

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Digital Communications and Networks 2024年第3期10卷 519-527页

作者： jiale Wu Celimuge Wu Yangfei Lin Tsutomu Yoshinaga Lei Zhong Xianfu chen Yusheng ji The University of Electro-Communication Tokyo182-8585Japan Toyota Motor Corporation Tokyo112-8701Japan VTT Technical Research Centre of Finland OuluFinland National Institute of Informatics(NII) Tokyo101-8430Japan

With the rapid development of artificial intelligence and the widespread use of the Internet of Things, semantic communication, as an emerging communication paradigm, has been attracting great interest. Taking image transmission as an example, from the semantic communication's view, not all pixels in the images are equally important for certain receivers. The existing semantic communication systems directly perform semantic encoding and decoding on the whole image, in which the region of interest cannot be identified. In this paper, we propose a novel semantic communication system for image transmission that can distinguish between Regions Of Interest (ROI) and Regions Of Non-Interest (RONI) based on semantic segmentation, where a semantic segmentation algorithm is used to classify each pixel of the image and distinguish ROI and RONI. The system also enables high-quality transmission of ROI with lower communication overheads by transmissions through different semantic communication networks with different bandwidth requirements. An improved metric θPSNR is proposed to evaluate the transmission accuracy of the novel semantic transmission network. Experimental results show that our proposed system achieves a significant performance improvement compared with existing approaches, namely, existing semantic communication approaches and the conventional approach without semantics.

关键词： Semantic Communication Semantic segmentation Image transmission Image compression Deep learning

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Secreted Frizzled-Related Protein 5 Mediates Wnt5a Expression in Microcystin-Leucine-Arginine-Induced Liver Lipid Metabolism Disorder in Mice

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Biomedical and Environmental Sciences 2024年第8期37卷 850-864页

作者： Meiyan Yang Furong Yu Qianqian ji Huiying Zhang jiaxiang Zhang Daojun chen Department of Occupational Health and Environmental Health School of Public HealthAnhui Medical UniversityHefei 230032AnhuiChina School of Medical Technology Anhui Medical CollegeHefei 230601AnhuiChina

Objective Microcystin-leucine-arginine(MC-LR)exposure induces lipid metabolism disorders in the *** frizzled-related protein 5(SFRP5)is a natural antagonist of winglesstype MMTV integration site family,member 5A(Wnt5a)and an anti-inflammatory *** this study,we aimed to investigate whether MC-LR can induce lipid metabolism disorders in hepatocytes and whether SFRP5,which has anti-inflammatory effects,can alleviate the effects of hepatic lipid metabolism by inhibiting the Wnt5a/Jun N-terminal kinase(JNK)*** We exposed mice to MC-LR in vivo to induce liver lipid metabolism ***,mouse hepatocytes that overexpressed SFRP5 or did not express SFRP5 were exposed to MC-LR,and the effects of SFRP5 overexpression on inflammation and Wnt5a/JNK activation by MC-LR were *** MC-LR exposure induced liver lipid metabolism disorders in mice and significantly decreased SFRP5 mRNA and protein levels in a concentration-dependent ***5 overexpression in AML12cells suppressed MC-LR-induced *** of SFRP5 also inhibited Wnt5a and phosphorylation of *** MC-LR can induce lipid metabolism disorders in mice,and SFRP5 can attenuate lipid metabolism disorders in the mouse liver by inhibiting Wnt5a/JNK signaling.

关键词： Jun N-terminal kinase Secreted frizzled-related protein 5 Wnt5a Hepatic lipid metabolism disorder

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Palladium-catalyzed stereoselective decarboxylative[4+2]cyclization of 2-methylidenetrimethylene carbonates with pyrrolidone-derived enones:Straightforward access to chiral tetrahydropyran-fused spiro-pyrrolidine-2,3-diones

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Chinese Chemical Letters 2024年第6期35卷 279-282页

作者： ke Zhang Sheng Zuo Pengyuan You Tong Ru Fen-Er chen key Laboratory of Natural Medicines of the Changbai Mountain Ministry of EducationCollege of PharmacyYanbian UniversityYanji 133002China College of Chemistry and Chemical Engineering Jiangxi Normal UniversityNanchang 330022China Engineering Center of Catalysis and Synthesis for Chiral Molecules Fudan UniversityShanghai 200433China Shanghai Engineering Center of Industrial Catalysis for Chiral Drugs Shanghai 200433China

A novel asymmetric[4+2]cycloaddition of 2-methylidenetrimethylene carbonate with pyrrolidonederived enones has been achieved to produce the functionalized tetrahydropyran-fused spirocyclic scaffolds via *** array of enantioenriched spiro-pyrrolidine-2,3-diones bearing adjacent quaternary and tertiary stereocenters are obtained in high yields with excellent enantioselectivities(up to 96% yield and 99% ee).The further transformation of the product has been accomplished for the construction of medical interesting β^(2,2)-amino acids and β-*** mechanistic research was well conducted.

关键词： Pyrrolidine-2,3-diones 2-Methylidenetrimethylene carbonate Asymmetric annulation Spiroheterocycles Allylic 1,3-strain

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A novel method for calculating broadband electrical performance of high-speed aircraft radome under thermo-mechanical-electrical coupling

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Chinese Journal of Aeronautics 2024年第9期37卷 463-474页

作者： jianmin ji jianhua REN Xunya jiANG Wei WANG Huilong YU Kai YIN Bo chen Beijing Institute of Remote Sensing Equipment Beijing 100854China Shanghai Dong Jun Information and Technology Co.Ltd Shanghai 200050China

The electrical performance of radomes on high-speed aircraft can be influenced by the thermal and mechanical loads produced during high-speed flight,which can affect the detection dis-tance and accuracy of the guidance *** paper presents a new method that uses the Finite Difference Time Domain(FDTD)method to calculate the electrical performance of radomes under Thermo-Mechanical-Electrical(TME)*** method can accurately characterize the effects of material dielectric temperature drift and structural deformation on the electrical performance of the radome under flight conditions,enabling high-precision full-wave calculations of the broadband electrical performance of the *** method initiates by utilizing a Finite Element Grid Model(FE-GM)of the radome to sequentially acquire the radome's response temperature field and structural deformation field through thermal and mechanical ***,spatial mapping techniques are developed to accurately incorporate the dielectric temperature drift and structural deformation of the radome into its Yee grid Electromagnetic(EM)simulation model.A verification case was designed to test the proposed method,and the results confirmed its high computational ***,the effectiveness and necessity of the method were further demonstrated by analyzing the electrical performance of a fused silica ceramic radome used on a high-speed aircraft.

关键词： High-speed aircraft Radomes Thermo-Mechanical-Electrical(TME)coupling Finite Difference Time Domain(FDTD)method Spatial mapping

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