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Elastic wave propagation and scattering in prestressed porous rocks

Science China Earth Sciences 2020年第9期63卷 1309-1329页

作者： Li-Yun fu bo-ye fu Weijia SUN Tongcheng HAN Jianlin LIU Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao 266580China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Institutions of Earth Science Chinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

Poro-acoustoelastic theory has made a great progress in both theoretical and experimental aspects,but with no publications on the joint research from theoretical analyses,experimental measurements,and numerical *** key issues challenge the joint research with comparisons of experimental and numerical results,such as digital imaging of heterogeneous poroelastic properties,estimation of acoustoelastic constants,numerical dispersion at high frequencies and strong heterogeneities,elastic nonlinearity due to compliant pores,and contamination by boundary *** poroacoustoelastic theory,valid for the linear elastic deformation of rock grains and stiff pores,is modified by incorporating a dualporosity model to account for elastic nonlinearity due to compliant pores subject to high-magnitude loading stresses.A modified finite-element method is employed to simulate the subtle effect of microstructures on wave propagation in prestressed digital *** measure the heterogeneity of samples by extracting the autocorrelation length of digital cores for a rough estimation of scattering *** conductexperimental measurements with a fluid-saturated sandstone sample under a constant confining pressure of 65 MPa and increasing pore pressures from 5 to 60 *** simulations for ultrasound propagation in the prestressed fluid-saturated digital core of the sample are followed based on the proposed poro-acoustoelastic model with compliant *** results demonstrate a general agreement between experimental and numerical waveforms for different stresses,validating the performance of the presented modeling *** excellent agreement between experimental and numerical coda quality factors demonstrates the applicability for the numerical investigation of the stress-associated scattering attenuation in prestressed porous rocks.

关键词： Poro-acoustoelasticity with compliant pores Elastic waves Prestressed porous rocks Numerical modeling Stressinduced scattering attenuation

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High-dense nanocrystalline W-based alloy prepared by hot isostatic pressing with uniform microstructure, ultrahigh hardness and good thermal stability

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Tungsten 2025年第1期7卷 120-136页

作者： Zao-Ming Wu Lin He Lin-Sen ye Xiao-Feng Yang Jia-Jia Zhang Hong-bo Lei Institute of Materials China Academy of Engineering Physics

High-density uniform microstructure nanocrystalline W-10wt.% Cr-5wt.% Y（W-10Cr-5Y） alloy with an average grain size of 85 nm and a relative density of 99.8% was successfully prepared.W-Cr-Y alloys with different amounts of second-phase particles were prepared by high-energy ball milling and hot isostatic pressing *** effects of composition design,ball milling parameters,and sintering parameters on the microstructure of W-Cr-Y alloys were studied.A feasible technology for controlling the synthesis of high-density nanocrystalline W-based alloys has been *** microstructure analysis of nanocrystalline W-10Cr-5Y alloy shows that there are two types of doping in the second phase:intergranular doping and intragranular *** "uniform distribution YOx-rich particles" effectively suppresses the grain growth of W and leads to the formation of nanocrystalline W-10Cr-5Y alloy.W-10Cr-5Y has an ultra-high hardness,with a Vickers hardness of 1312±12 kgf·***-temperature annealing treatment shows that W-10Cr-5Y has good thermal stability at 1000 and1100℃,as demonstrated by the comparison of Vickers hardness and grain size between annealed and unannealed alloys.

关键词： Hot isostatic pressing Microstructure Nanocrystalline tungsten Thermal stability Vickers hardness

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LAMOST二维光纤光谱抽谱方法的研究

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天文学报 2008年第3期49卷 327-338页

作者：崔波叶中付白仲瑞中国科学技术大学信号统计处理研究室合肥230027

对LAMOST二维光纤光谱数据处理系统中的抽谱方法进行了阐述,分析了抽谱中关键参数采样点选取对结果的影响,并根据高斯分布函数的特性以及实验情况确定了采样点的选取范围,解决了抽谱结果出现负值的问题.进一步针对大噪声背景下抽谱存在... 详细信息

对LAMOST二维光纤光谱数据处理系统中的抽谱方法进行了阐述,分析了抽谱中关键参数采样点选取对结果的影响,并根据高斯分布函数的特性以及实验情况确定了采样点的选取范围,解决了抽谱结果出现负值的问题.进一步针对大噪声背景下抽谱存在误差较大的问题,提出了基于频域滤波思想的改进抽谱方法.首先利用快速傅立叶变换和低通滤波器将影响光纤实际轮廓的尖锐噪声滤除,然后再进行正常的抽谱.利用LAMOST二维光纤光谱数据处理系统提供的模拟数据进行了实验测试,结果表明改进抽谱方法的可行性与有效性.

关键词：望远镜技术频谱仪

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ICA-Net: improving class activation for weakly supervised semantic segmentation via joint contrastive and simulation learning

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Optoelectronics Letters 2025年第3期21卷 188-192页

作者： ye Zhuang LIU Ruyu SUN bo School of Information Engineering Chengdu Aviation Vocational and Technical College School of Computer Science and Engineering Hangzhou Normal University Quanzhou Institute of Equipment Manufacturing Haixi Institutes Chinese Academy of Sciences

In the field of optoelectronics, certain types of data may be difficult to accurately annotate, such as high-resolution optoelectronic imaging or imaging in certain special spectral ranges. Weakly supervised learning can provide a more reliable approach in these situations. Current popular approaches mainly adopt the classification-based class activation maps (CAM) as initial pseudo labels to solve the task.

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Graphene oxide wrapped-silica microspheres humidity sensor with fast response/recovery, high sensitivity, and selectivity for pig respiratory rate monitoring

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Science China Technological Sciences 2025年

作者： Jing LI bo LI Ziqi LIAO Yunhui DUAN Xinglan fu Yuehua HUANG Guanglin LI College of Engineering and Technology Southwest University Modern Agricultural Equipment Research Institute Xihua University

Respiratory rate monitoring is of great significance in pig healthy breeding for the early detection and timely prevention of respiratory diseases. Humidity sensing is an important noncontact method to monitor pig respiration, which does not cause direct harm to pigs and meets the requirements of animal welfare. This paper proposes a humidity sensor based on graphene oxide wrapped-silica microspheres （GO@SiO2）. First, the sensor shows fast response/recovery performances of0.24/0.73 s. Experiments demonstrate that the wrapped microsphere structure can inhibit water aggregation. It is speculated that the wrapped microsphere structure can inhibit the stacking of GO, and its curved surface can promote the evaporation of water molecules. Second, the sensor shows a high sensitivity of 1.2%/%RH–4.2%/%RH in 11%–95%RH range. This can be attributed to different sensing mechanisms, from hopping transport to increasing ion transport, leading to a significant change in the sensor’s resistance. Third, the sensor shows selectivity to water molecules due to the hydrophilic characteristic of GO and the significant increase in conductivity by ion transport. Finally, the sensor is applied to realize the respiratory rate monitoring of adult pigs and piglets.

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Synthesis of chiral phosphine derivatives through a copper（I）-catalyzed desymmetric SNAr reaction

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Science China Chemistry 2025年

作者： Shuai Zhang Pei-Zhi Liu Yan-bo Li Qi Zhang Jun-Zhao Xiao Yi-Fan Wang Tian-Yu Wei Jia-Wei Jiang ye Wang Qian Peng Liang Yin Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences State Key Laboratory of Elemento-Organic Chemistry and Tianjin Key Laboratory of Biosensing and Molecular Recognition College of Chemistry Frontiers Science Center for New Organic Matter Nankai University Haihe Laboratory of Sustainable Chemical Transformations

Axially chiral phosphines are a class of extremely important ligands in asymmetric catalysis. Herein, an unprecedented copper（I）-catalyzed asymmetric SNAr reaction with HP（S）R2is uncovered, which delivers a series of axially chiral phosphine derivatives in high yields with excellent enantioselectivity. furthermore, the diastereoselective reaction with the kinetic resolution of racemic HP（S）ArR proceeds smoothly, providing the products with moderate diastereoselectivity and excellent enantioselectivity. Control experiments indicate that HP（S）Ph2is much more active than HPPh2and HP（O）Ph2as the pronucleophile in the present reaction. It is found that the SNAr reaction （the first SNAr） proceeds in a desymmetric manner, providing the desired chiral products while a continued SNAr reaction （the second SNAr） slightly occurs in a kinetic resolution manner in the present catalytic system, which enhances the ee of the desired chiral products. DFTcalculations support a concerted reaction pathway rather than a step-wise mechanism. Finally, axially chiral olefin-phosphines produced by the present method work as suitable ligands in Pdcatalyzed asymmetric allylic substitution with C-, N-, and O-nucleophiles and Rh-catalyzed asymmetric addition of arylboronic acid to benzil.

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On the Hosoya index of graphs

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Applied Mathematics(A Journal of Chinese Universities) 2010年第2期25卷 155-161页

作者： WANG bo ye Cheng-fu YAN Li-ying Department of Mathematics Qinghai Normal University Xining 810008 China Qinghai Communications Technical College Xining 810003 China.

Let G be a （molecular） graph. The Hosoya index Z（G） of G is defined as the number of subsets of the edge set E（G） in which no two edges are adjacent in G, i.e., Z（G） is the total number of matchings of G. In this paper, we determine all the connected graphs G with n ＋ 1 ≤ Z（G） ≤5n - 17 for n ≥ 19. As a byproduct, the graphs of n vertices with Hosoya index from the second smallest value to the twenty first smallest value are obtained for n ≥ 19.

关键词： Graph Hosoya index matching

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Advances and applications in single-cell and spatial genomics

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Science China Life Sciences 2025年

作者： Jingjing Wang Fang ye Haoxi Chai Yujia Jiang Teng Wang Xia Ran Qimin Xia Ziye Xu Yuting fu Guodong Zhang Hanyu Wu Guoji Guo Hongshan Guo Yijun Ruan Yongcheng Wang Dong Xing Xun Xu Zemin Zhang Beijing Advanced Innovation Center for Genomics (ICG) Peking University Guangdong Provincial Key Laboratory of Genome Read and Write BGI Research bone Marrow Transplantation Center of the First Affiliated Hospital & Liangzhu Laboratory Zhejiang University School of Medicine Life Sciences Institute and The Second Affiliated Hospital Zhejiang University BGI Research Biomedical Pioneering Innovation Center (BIOPIC) and School of Life Sciences Peking University Academy for Advanced Interdisciplinary Studies Peking University Institute of Hematology Zhejiang University Department of Laboratory Medicine of The First Affiliated Hospital & Liangzhu Laboratory Zhejiang University School of Medicine Center for Stem Cell and Regenerative Medicine Zhejiang University School of Medicine Zhejiang Provincial Key Lab for Tissue Engineering and Regenerative Medicine Dr.Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine

The applications of single-cell and spatial technologies in recent times have revolutionized the present understanding of cellular states and the cellular heterogeneity inherent in complex biological systems. These advancements offer unprecedented resolution in the examination of the functional genomics of individual cells and their spatial context within tissues. In this review, we have comprehensively discussed the historical development and recent progress in the field of single-cell and spatial genomics. We have reviewed the breakthroughs in single-cell multi-omics technologies, spatial genomics methods, and the computational strategies employed toward the analyses of singlecell atlas data. furthermore, we have highlighted the advances made in constructing cellular atlases and their clinical applications,particularly in the context of disease. Finally, we have discussed the emerging trends, challenges, and opportunities in this rapidly evolving field.

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生物处理改善大米和大米粉特性的研究进展

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食品与发酵工业 2025年第1期51卷 345-353页

作者：王钵柴宝玉叶发银雷琳赵国华西南大学食品科学学院重庆400715 川渝共建特色食品重庆市实验室重庆400715

大米和大米粉是主食及无麸质食品生产的主要原料,其特性对最终产品的品质有重要影响。研究表明,对大米和大米粉进行适当的改性处理,可改善其特性并提升其所生产产品的质量。该文在查阅相关文献的基础上,概括了3类生物处理方法(微生物发... 详细信息

大米和大米粉是主食及无麸质食品生产的主要原料,其特性对最终产品的品质有重要影响。研究表明,对大米和大米粉进行适当的改性处理,可改善其特性并提升其所生产产品的质量。该文在查阅相关文献的基础上,概括了3类生物处理方法(微生物发酵、发芽、酶处理)对大米和大米粉主要成分、淀粉的糊化特性和热特性、营养安全特性以及加工特性影响的研究进展,并对利用生物处理方法改善大米和大米粉特性的研究进行了展望。该文对从原料学角度开发安全、可靠的大米和大米粉特性生物调控技术,推动大米制品品质提升有较好的参考价值。

关键词：大米淀粉发酵发芽酶处理

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Zircon SHRIMP U–Pb geochronology,geochemistry,and geological significance of dacite in the Zhesang gold district,southeast Yunnan Province,China

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Acta Geochimica 2023年第2期42卷 290-308页

作者： bo Wang Jiasheng Wang Jinlong Li Hao fu Yuehua Ma Bin ye Earth Science Department of Land Resources College Kunming University of Science and TechnologyKunming 650093China Yunnan Bureau of Coalfield Geology Kunming 650034China

The Late Paleozoic and Mesozoic tectonic framework of the Nanpanjiang Basin has much been ***,the middle-acid volcanic rock,dacite,exposed to the Zhesang gold district,southeast Yunnan Province,has been *** results show that the dacite belongs to a calc-alkaline series,SiO_(2)contents range from 62.79 to 76.66 wt%.Zircon SHRIMP U–Pb dating of dacite demonstrates that they were formed in the Early Triassic(247.8±1.7 Ma,MSWD=1.2).All samples exhibit enrichment in LILE(***,K,Th,and U),and depletion in HFSE(***,Ta,and Ti),which has the geochemical affinity of I-type ***–La/Sm and La–La/Yb discrimination diagrams show that the partial melting,mainly of the mafic lower crust,of rocks,plays a major role in the formation *** dacite has low initial ^(87)Sr/^(86)Sr ratios(0.706954 to 0.708589)and negative ε_(Nd)(t)values(-11.77 to-10.88).Zircons in dacite have ε_(Hf)(t)values of-16.2 to-8.3,and the two-stage Hf model ages are 1799–2301 Ma,mostly concentrated between 1800 and 1900 Ma,indicating that the magma source area is the reconstructed ancient lower crust mixed with some mantle materials,and crystal fractionation process underwent in the late stage of magma *** study reveals that the arc-volcanic rocks of the Early Triassic in the southern margin of the Nanpanjiang Basin were formed by the subduction of the Late Paleozoic ocean basin within the border region between China and Vietnam.

关键词： Dacite Zircon SHRIMP U–Pb geochronology Sr–Nd–Hf isotope Geochemistry Arcvolcanic rock Late Paleozoic ocean basin

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