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Late Paleozoic to early Mesozoic volcanic-sedimentary history of the southeastern margin of the Central Asian Orogenic Belt: Timing of uplift of the Inner Mongolia paleo-uplift

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Science China Earth Sciences 2025年第1期68卷 297-309页

作者： Wenxing HAO Jin-Hui YANG Guang ZHU State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences School of Resource and Environmental Engineering Hefei University of Technology

The Kulun region is located in the eastern Bainaimiao arc belt on the southeastern margin of the Central Asian Orogenic Belt(CAOB), adjacent to the North China Craton(NCC) to the south. This region records the closure of the PaleoAsian Ocean during the Paleozoic to early Mesozoic and is key to study the tectonic evolution of the northern margin of the *** conducted zircon U-Pb geochronology and Hf isotope analysis of volcanic-sedimentary and intrusive rocks in the Kulun region. The volcanic-sedimentary rocks were previously assigned an early Carboniferous age, but include volcanic rocks with ages of 267–266 Ma and sedimentary rocks with youngest detrital zircon age peaks of 265–244 Ma, which were intruded by a granite with an age of 242 Ma. This indicates that these rocks are actually middle Permian to Middle Triassic in age(267–242Ma) and correspond to the Qingfengshan and Liujiagou formations. Moreover, two volcanic rock samples have high εHf(t) values(+1.6 to +16.1) and relatively young two-stage Hf model ages(1095–327 Ma), indicating their sources associated with the CAOB. The age spectra and Hf isotopic characteristics of detrital zircons from the sedimentary rocks suggest that, during the middle Permian to Middle Triassic, the sedimentary provenance in the Kulun region was mainly the CAOB. However, by the Early Jurassic, the provenance changed to the NCC(i.e., the Inner Mongolia Paleo-uplift, IMPU). This result, combined with the development of a series of conglomerates on the northern margin of the NCC in the Late Triassic(i.e., Xingshikou, Xiaoyingzi,and Xiaohekou formations), indicates the Kulun region experienced an abrupt change in paleogeography during the Late Triassic, with the IMPU undergoing significant uplift and thus becoming the main sediment source in the Kulun region. Based on the Late Triassic alkaline igneous belt(235–215 Ma) in the IMPU, we speculate that this uplift was caused by detachment of the southward-subducting Paleo-Asian oceanic

关键词： Central Asian Orogenic Belt the North China Craton Zircon geochronology Hf isotopes Inner Mongolia Paleo-uplift

Advanced Functional Electromagnetic Shielding Materials:A Review Based on Micro‑Nano Structure Interface Control of Biomass Cell Walls

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Nano-Micro Letters 2025年第1期17卷 98-134页

作者： Yang Shi Mingjun Wu Shengbo Ge Jianzhang Li Anoud Saud Alshammari Jing Luo Mohammed A.Amin Hua Qiu Jinxuan Jiang Yazeed M.Asiri Runzhou Huang Hua Hou Zeinhom M.El‑Bahy Zhanhu Guo Chong Jia Kaimeng Xu Xiangmeng Chen Co‑Innovation Center of Efficient Processing and Utilization of Forest Resources College of Materials Science and EngineeringNanjing Forestry UniversityNanjing 210037People’s Republic of China State Key Laboratory of Efficient Production of Forest Resourced Beijing Forestry UniversityQinghua East Road 35Haidian DistrictBeijing 100083People’s Republic of China Department of Physics Faculty of Sciences‑ArarNorthern Border UniversityArar 91431Saudi Arabia Department of Chemistry College of ScienceTaif UniversityP.O.Box 1109921944 TaifSaudi Arabia Shaanxi Key Laboratory of Macromolecular Science and technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China Integrated Composites Lab Department of Mechanical and Construction EngineeringNorthumbria UniversityNewcastle Upon Tyne NE18STUK College of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024People’s Republic of China Department of Chemistry Faculty of ScienceAl-Azhar UniversityNasr CityCairo 11884Egypt Yunnan Provincial Key Laboratory of Wood Adhesives and Glued Products International Joint Research Center for Biomass MaterialsSouthwest Forestry UniversityKunming 650224People’s Republic of China School of Science Henan Agricultural UniversityZhengzhou 450002People’s Republic of China

Research efforts on electromagnetic interference(EMI)shielding materials have begun to converge on green and sustainable biomass *** materials offer numerous advantages such as being lightweight,porous,and *** to their porous nature,interfacial compatibility,and electrical conductivity,biomass materials hold significant potential as EMI shielding *** concerted efforts on the EMI shielding of biomass materials have been reported,this research area is still relatively new compared to traditional EMI shielding *** particular,a more comprehensive study and summary of the factors influencing biomass EMI shielding materials including the pore structure adjustment,preparation process,and micro-control would be *** preparation methods and characteristics of wood,bamboo,cellulose and lignin in EMI shielding field are critically discussed in this paper,and similar biomass EMI materials are summarized and *** composite methods and fillers of various biomass materials were *** paper also highlights the mechanism of EMI shielding as well as existing prospects and challenges for development trends in this field.

关键词： Biomass materials Electromagnetic interference shielding Micro-nano structure interface control Conductivity

Erbium Doped Fiber Amplifier Gain Flattening Using Long-Period Fiber Gratings

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Chinese Physics Letters 1999年第7期16卷 513-515页

作者： CHEN Gen-xiang JIAN Shui-sheng LI Tang-jun LIU Chun-ning XIE Zeng-hua Institute of Lightwave technology Northern Jiaotong UniversityBeijing 100044

Based on theoretical and experimental studies on the optical properties of long-period gratings(LPGs),an erbium doped fiber amplifier(EDFA)gain equalizer was fabricated by writing three long period gratings with designed properties in hydrogen-loaded standard single-mode *** LPGs were written by a KrF excimer laser at 248 nm with amplitude *** gain variation of±3dB in the EDFA is reduced to±0.3 dB with a bandwidth of 30 nm and the total insertion loss of the device is less than 0.3 dB.

关键词： amplifier Erbium KrF

Electron Aceleration Process in ZnS-Type Thin Film Electroluminescence Devices

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Chinese Physics Letters 1999年第3期16卷 217-219页

作者： ZHAO Hui WANG Yong-sheng XU Zheng XU Xu-rong Institute of Optoelectronic technology Northern Jiaotong UniversityBeijing 100044

Based on the calculations about scattering rates,the electron acceleration process of ZnS-type thin film electroluminescent devices is studied in detail through Monte Carlo *** acceleration time and drift length before the balance of acceleration and Scattering are about 200 fs and 30-40nm,*** steady average kinetic energy of electrons increases with electric *** emission process of electrons trapped at interface states only affects the acceleration process of electron transport and makes no influence on steady *** explanations about the“dead layer”phenomenon and the overshoot in the averge drift velocity are proposed based on the calculations.

关键词： method. field. state.

Transient transport of electrons in thin film electroluminescent devices

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Science China(Technological Sciences) 1999年第3期42卷 282-287页

作者：赵辉王永生徐征徐叙瑢 Institute of Optoelectronic technology Northern Jiaotong University Beijing China

Transient transport of electrons in ZnS-type thin film electroluminescent devices is studied with Monte Carlo method. The variation rule of electrons’ average kinetic energy, average drift velocity and intervalley transfer process are obtained. The transient time and drift length before the balance of acceleration and scattering are about 200 fs and 30-40 nm, respectively. Field emission process of electrons trapped at interface states only affects the transient process of electron transport and makes no influence on the steady state. The new explanations about the 'dead layer' phenomenon and the overshoot in the average drift velocity are proposed based on the calculation results.

关键词： electroluminescence electron transport transient process Monte Carlo method.

The role of Sm ions in optical storage of SrS: Eu,Sm

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Science China Mathematics 2001年第9期44卷 1189-1196页

作者：何志毅王永生孙力侯延冰徐叙■ Institute of Optoelectronic technology Northern Jiaotong University Beijing China

The optical absorption spectra of infrared stimulable phosphor SrS:Eu, Sm in the saturat-ed and bleached states of optical storage were investigated. The valence and number of Sm3+ ions were examined via the Sm3+ 4f-4f absorption in near-infrared region. It was found that the broad band absorption corresponding to the transition for electrons stimulated from the traps to the conduction band is decreased at the wavelengths of Sm3+ absorption lines. The dependence of optical storage on Sm concentration was measured. A new trapping mechanism in SrS: Eu, Sm was presented based on our experimental results and the role of Sm ions was identified.

关键词： electron capturing electron trap optical storage samarium.

Impacts of ice cover on local scour around semi-circular bridge abutment

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Journal of Hydrodynamics 2014年第1期26卷 10-18页

作者： WU Peng HIRSHFIELD Faye SUI Jueyi 王军陈胖胖 Environmental Engineering University of Northern British Columbia School of Civil Engineering Hefei University of Technology

The presence of ice cover in winter can significantly change the flow field around bridge abutments, which can also cause a different local scour pattern. To investigate the impacts of ice cover, results from a recent flume experiments were presented. Smooth and rough ice covers were created to investigate the impacts of ice cover roughness on the scour geometry around the semi-circular abutment. Three bed materials were used, with 50D s of 0.58 mm, 0.50 mm, 0.47 mm respectively. Scour volume and scour area were calculated. It was found that the maximum scour depth was located 75o inclined to the flume wall. Under rough ice cover, the scour area and scour depth were the largest. An empirical equation on the maximum scour depth was also developed.

关键词： ice cover local scour semi-circular abutment maximum scour depth scour pattern

The generation of group delay ripple of chirped fiber gratings

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Chinese Optics Letters 2004年第1期2卷 18-20页

作者：谭中伟刘艳宁提纲简水生 Institute of Lightwave technology Northern Jiaotong University Beijing 100044

The analysis of the group delay ripple (GDR) generated by chirped fiber gratings is developed based on the Fabry-Perot (F-P) resonator. It shows clearly how the GDR is generated and why the periods of GDR varies along the chirped fiber gratings. It could also explain why apodization could suppress the GDR and how apodization affects the chirp of the grating. The theory could be used to devise the apodization of fiber gratings.

关键词： GDR The generation of group delay ripple of chirped fiber gratings

All-Fiber Ring Resonator Gyroscope

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Chinese Physics Letters 1995年第4期12卷 213-216页

作者： YAO Yi SHI Kun LU Weidong JIAN Shuisheng Institute of Lightwave technology Northern Jiaotong UniversityBeijing 100044

An all-fiber resonator optic gyroscope employing a spliceless polarization maintaining fiber resonator with 90°polarization rotation in the lapped coupler is presented.A frequency-modulation spectroscopy technique using two piezoelectric transducer phase modulators has been theoretically analyzed and experiment ally demonstrated for rotation *** short term bias stability better than 16°/h with integration time of 10s has been *** main error sources of optical system are discussed and some reduction measures are suggested.

关键词： polarization resonator fiber