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Growth mechanisms and environmental implications of carbonate concretions from the ～ 1.4Ga Xiamaling Formation, North China

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Journal of Palaeogeography 2019年第3期8卷 285-300页

作者： An-Qi Liu Dong-Jie Tang Xiao-Ying Shi Li-Min Zhou Xi-Qiang Zhou Mo-Han Shang Yang Li Hu-yue song State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences (Beijing) Beijing 100083 China lnstitute of Earth Sciences China University of Geosciences (Beijing) Beijing 100083 China School of Earth Sciences and Resources China University of Geosciences (Beijing) Beijing 100083 China National Research Center for Geoanalysis Beijing 100037 China Key Lab of Petroleum Resources Research Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China State Key Laboratory of Biogeology and Environ mental Geology China University of Geosciences (Wuhan) Wuhan 430074 China

Carbonate concretions provide unique records of ancient biogeochemical processes in marine sediments, and have the potential to reflect seawater chemistry indirectly. In fine-siliciclastic settings, they preferentially form in organicrich mudstones, owing to a significant fraction of the bicarbonate required for carbonate precipitation resulted from the decomposition of organic matter in sediments. In the Member IV of the Xiamaling Formation(ca. 1.40–1.35 Ga), North China, however, carbonate concretions occur in organic-poor green silty shales(avg. TOC = ~ 0.1 wt%).In order to elucidate the mechanism of the concretion formation and their environmental implications, a thorough study on the petrographic and geochemical compositions of the concretions and their host rocks was ***-to microscopic fabrics, including deformed shale laminae surrounding the concretions, "cardhouse"structures of clay minerals and calcite geodes in the concretions, indicate that these concretions are of early diagenetic origin prior to the significant compaction of clay minerals. The carbon isotope compositions of the concretions(-1.7‰ to + 1.5‰) are stable and close to or slightly lower than that of the contemporaneous seawater, indicating that the bicarbonates required for the concretion formation were mainly sourced from seawater by diffusion rather than produced by methanogenesis or anoxic oxidation of methane(AOM); the rare occurrence of authigenic pyrite grains in the concretions likely indicates that bacterial sulfate reduction(BSR) did not play a significant role in their formation either. Almost all the calcite in the concretions has low Mn–Fe in nuclei but high Mn–Fe in rims with average Mn/Fe ratio close to 3.3. The calcite shows positive Ce anomalies(avg. 1.43)and low Y/Ho ratios(avg. 31). This evidence suggests that Mn reduction is the dominant process responsible for the formation of calcite rims while nitrate reduction probably triggered the precipitation of calcite

关键词： Mid-Proterozoic Carbonate concretion Early diagenesis Manganese reduction Bicarbonate

ICESat-2激光雷达海面信号提取和海浪要素计算

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红外与激光工程 2023年第2期52卷 204-212页

作者：周智标周辉马跃宋越李松武汉大学电子信息学院湖北武汉430072

美国NASA于2018年发射的ICESat-2 (The Ice, Cloud, and land Elevation Satellite-2)卫星上搭载的ATLAS (Advanced Topographic Laser Altimeter System)是目前为止全球唯一一个对地观测的星载光子计数激光雷达,具有较高的轨向空间采样率,为用遥感的方法探测海浪要素提供了可能。光子计数激光雷达用于海浪探测的前提是能够准确地提取来自海面的信号光子,并确定瞬时的海面廓线。迄今为止,用星载光子计数激光雷达探测海面形态和海浪要素的研究鲜见报道,也缺少专门针对海面信号光子的提取方法。基于海面信号光子的分布特点,文中提出了一种新的信号提取算法:首先通过直方图统计及自适应的阈值选取完成对海面回波光子的粗去噪;然后基于激光雷达光斑尺寸和海面波动特点,选取合适的搜索邻域计算信号点和噪声点密度,根据两者点密度差异对信号光子和噪声光子分类;最后用高斯函数拟合的方法进一步去除密度较大的后向散射噪声光子,最终得到来自海面反射的信号光子。利用上述算法提取了太平洋7个不同海况区域的海面信号光子和瞬时海面廓线并进一步计算出当地海浪的峰值波长和周期。将计算结果与同期欧洲中期天气预报中心(European Centre for Medium-Range Weather Forecasts, ECMWF)的全球大气再分析ERA5(ECMWF Re-Analysis5)数据作对比,在不同风速、水深的海域都获得了基本一致的结果,超过半数区域的海浪周期误差在5%以内,初步证明了星载光子计数激光雷达观测成果用于海浪要素计算的可行性。

关键词：激光雷达遥感 ICESat-2/ATLAS 海面信号去噪海浪要素计算

Polarized Spatial Splitting of Four-Wave Mixing Signal in Multi-Level Atomic Systems

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Chinese Physics Letters 2011年第4期28卷 118-121页

作者： FU Yu-Xin ZHAO Jin-Yan song yue DAI Guo-Xian HUO Shu-Li ZHANG Yan-Peng Key Laboratory for Physical Electronics and Devices of the Ministry of Education and Shaanxi Key Lab of Information Photonic Technique Xi’an Jiaotong UniversityXi’an 710049

We illustrate our experimental observation of the periodic changes of spatial splitting of the generated four-wave mixing(FWM)signal induced by different polarization states of one of the dressing *** is pointed out that the changes of intensity of the dressing beam and the FWM signal have influences on the spatial splitting and their influences compete with each *** differences between p-and s-polarized FWM beams are *** influences of the dressing beams,which lead to the larger spatial splitting with different polarization states or frequency detuning,are observed as well.

关键词： splitting mixing polarized

管状阳极氧化铝模板的表面氧化应力分析及其应用研究

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功能材料 2013年第12期44卷 1690-1693,1698页

作者：乐松章园暨南大学物理系广东广州510632 暨南大学思源实验室广东广州510632

通过对高纯铝片预制铝管分别进行"外表面阳极氧化"(外氧化)和"内表面阳极氧化"(内氧化)制备了管状多孔氧化铝模板(AAO),考察了氧化过程中Al/Al2O3界面的应力影响。实验直观表明,"外氧化"过程中Al/Al2O3界面产生拉伸应力易导致管状模板... 详细信息

通过对高纯铝片预制铝管分别进行"外表面阳极氧化"(外氧化)和"内表面阳极氧化"(内氧化)制备了管状多孔氧化铝模板(AAO),考察了氧化过程中Al/Al2O3界面的应力影响。实验直观表明,"外氧化"过程中Al/Al2O3界面产生拉伸应力易导致管状模板产生轴向裂纹;而"内氧化"过程中Al/Al2O3界面产生压缩应力使管状模板更加紧密而不易破裂。研究结果表明,Al/Al2O3界面上拉伸应力的有效释放是获得无裂纹管状阳极氧化铝模板的关键。最后,利用管状氧化铝模板制备了放射状Cu纳米线阵列,并对其在膜渗透方面的应用进行了初步尝试。

关键词：阳极氧化铝管状模板微孔材料纳米线滤透

Interplay of Coexisting Odd-Order Wave Mixings in a Five-Level Atomic System

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Chinese Physics Letters 2011年第2期28卷 101-104页

作者： song yue HUO Shu-Li LI Pei-Ying SANG Su-Ling WANG Zhi-Guo ZHANG Yan-Peng Key Laboratory for Physical Electronics and Devices of the Ministry of Education&Shaanxi Key Lab of Information Photonic Technique Xi’an Jiaotong UniversityXi’an 710049

We experimentally investigate the interplay between two coexisting six-wave mixing(SWM)signals and the interference between coexisting four-wave mixing(FWM)and SWM signals in a five-level atomic system of85 *** two electromagnetically induced transparency windows gradually overlap in frequency,the competition between these two SWM signals ***,we report the experimental result which shows that the temporal interference with femtosecond time scales between FWM and SWM signals.

关键词： mixing transparency overlap

CdS/Si nanofilm heterojunctions based on amorphous silicon films:Fabrication,structures,and electrical properties

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Chinese Physics B 2021年第2期30卷 385-389页

作者： Yong Li Peng-Fei Ji yue-Li song Feng-Qun Zhou Hong-Chun Huang Shu-Qing Yuan Laboratory of Nano Optoelectronic Materials and Insulation Materials Pingdingshan UniversityPingdingshan 467000China

Shortening the distance between the depletion region and the electrodes to reduce the trapped probability of carriers is a useful approach for improving the performance of *** CdS/Si nanofilm heterojunctions are fabricated by using the radio frequency magnetron sputtering method to deposit the amorphous silicon nanofilms and Cd S nanofilms on the ITO glass in *** relation of current density to applied voltage(I-V)shows the obvious rectification *** the analysis of the double logarithm I-V curve it follows that below~2.73 V the electron behaviors obey the Ohmic mechanism and above~2.73 V the electron behaviors conform to the space charge limited current(SCLC)*** the SCLC region part of the traps between the Fermi level and conduction band are occupied,and with the increase of voltage most of the traps are *** is believed that Cd S/Si nanofilm heterojunction is a potential candidate in the field of nano electronic and optoelectronic devices by optimizing its fabricating procedure.

关键词： magnetron sputtering CdS/Si nanofilm heterojunctions electron behaviors SCLC mechanisms

Measurements of the Cross-sections of Produced Short-Lived Nuclei Induced by Neutrons around 14 MeV on Isotopes of Tungsten

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Chinese Physics Letters 2019年第11期36卷 10-13页

作者： Xiao-Jun Sun Feng-Qun Zhou yue-Li song Yong Li Peng-Fei Ji Xin-Yi Chang Henan Key Laboratory of Research for Central Plains Ancient Ceramics Pingdingshan UniversityPingdingshan 467000 School of Electrical and Mechanical Engineering Pingdingshan UniversityPingdingshan 467000

New experimental cross-section data for the^180 W(n,2 n)^179 mW,^186 W(n,2 n)185 mW and186 W(n,p)186 Ta reactions at the neutron energies of 13.5 and 14.4 MeV are obtained by the activation technique. The neutron beams are produced by means of the3 H(d,n)4 He reaction. The gamma activities of the product nuclei are measured by a high-resolution gamma-ray spectrometer with a coaxial high-purity germanium detector. The neutron fluence is determined using the monitor reaction^93 Nb(n,2 n)^92 mNb. The results in the current work are discussed and compared with the measurement results found in the literature. It is shown that these higher accuracy experimental cross-section data around the neutron energy of 14 MeV agree with some previous experimental values from the literature within experimental uncertainties.

关键词： technique. reaction. purity

Bending Loss Calculation of a Dielectric-Loaded Surface Plasmon Polariton Waveguide Structure

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Chinese Physics Letters 2010年第2期27卷 263-266页

作者：岳嵩李智陈建军龚旗煌 State Key Laboratory for Mesoscopic Physics and Department of Physics Peking University Beijing 100871

Based on full 3D finite element method simulations, the transmission of a dielectric-loaded surface plasmon polariton waveguide （DLSPPW） based 1/4 circle is calculated for a 90° bend model and a 270° bend model, respectively. It is found that the 270° bend model gives almost pure bending loss while the 90° bend model contains additional coupling loss. The models are applied to deduce the loss and unloaded quality factor of DLSPPW based waveguide ring resonators （WRRs） and the results of the 270° bend model agree well with direct simulating results of the WRRs. Thus the 270° bend model gives a fast and simple way to calculate bending loss and it is helpful for WRR design because no wavelength scan is needed.

关键词： Condensed matter: electrical magnetic and optical Surfaces interfaces and thin films Optics quantum optics and lasers

High-Performance Liquid Chromatography Fingerprint of Marine Traditional Chinese Medicine Haliotidis

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World Journal of Traditional Chinese Medicine 2022年第3期8卷 446-452页

作者： Qing Zhao Shu-yue song Meng-Qi Zhang Xin Li Yang Liu Chang-Yun Wang Key Laboratory of Marine Drugs The Ministry of Education of ChinaSchool of Medicine and PharmacyOcean University of ChinaLaboratory for Marine Drugs and BioproductsQingdao National Laboratory for Marine Science and TechnologyQingdaoChina Insect Biotechnology Justus Liebig University GiessenGiessenGermany

Objective: Haliotidis, the dried muscle of abalone, has long been used as a marine traditional Chinese medicine(TCM) due to its high medicinal and nutritive values, whereas few reports contributed to its quality control. This study aimed to establish the high-performance liquid chromatography(HPLC) fingerprints of Haliotidis. Materials and Methods: The HPLC fingerprints of Haliotidis, the manufacturing products of dried muscle of abalone, were analyzed by reverse-phase HPLC, using a YMC HPLC C18 column(250 mm × 4.6 mm, 5 μm).The gradient elution mode was applied with mobile phase starting from 5% acetonitrile and 0.1% phosphoric acid aqueous solution to 100%acetonitrile in 70 min at a flow rate of 1.0 mL/min. The detection wavelength was set at 190 nm. Results: Through compared the HPLC fingerprint chromatograms of 14 batches of Haliotidis, 25 peaks were assigned as the characteristic common peaks, of which one index component L-phenylalanine was identified by comparison with its standard substance. The established HPLC fingerprint analysis method of Haliotidis was validated with good precision, repeatability, and stability. Based on the above study, a reference HPLC fingerprint chromatogram of Haliotidis was proposed. Conclusions: It is the first time to establish the HPLC fingerprint chromatogram of TCM Haliotidis, which could contribute to the establishment of its quality control system.

关键词： Marine traditional Chinese medicine Haliotidis HPLC fingerprint quality control