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High frequency S wave envelope synthesis using a multiple non-isotropic scattering model: application to aftershocks from the 2008 Wenchuan earthquake

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Earthquake Engineering and Engineering Vibration 2013年第2期12卷 185-194页

作者： Lin gao jing Yueling Li Jianbo The State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Earthquake Engineering Research Division Dalian University of Technology

Based on the formulation of a multiple non-isotropic scattering process, a characteristic source time is introduced to define the initial impulse width of energy density at the source. An analytical expression of the initial intensity spectral density of a seismic wave is incorporated into the integral equation of seismic wave energy density. And, a recursive formula of Green＇s function is derived to obtain the higher order Green＇s function, which is included to describe the stronger non-isotropic scattering process. Then, the effect of the scattering pattern on the energy density envelope is investigated by the modified scattering theory. Significant differences arc found in the decay of the energy density envelopes with distances using different scattering patterns. The envelope synthesized by the forward dominated scattering pattern is larger than the results obtained by the isotropic and backward dominated scattering pattern. Different scattering patterns are also used to fit the observation data from the aftershocks of the 2008 Wenchuan earthquake. It is concluded that the envelopes synthesized by the forward scattering pattern can match the data better than the isotropic and backward dominated scattering cases, and a new interpretation of the coda wave is given. Finally, using the forward dominated scattering pattern, the envelope broadening of the observed data is reproduced.

关键词： non-isotropic scattering coda wave envelope broadening energy transport theory (radiative transfer theory) directional scattering coefficient ground motion

One-pot synthesis of diarylimidazolium salts from 1H-imidazole

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Chinese Chemical Letters 2013年第9期24卷 773-776页

作者： Tai-Yong Lv lei Yang Yin-Song Zhao Fei-Jie Song jing-Bo Lan jing-Song You Ge gao Key Laboratory of Green Chemistry and Technology of Ministry of Education College of Chemistry

Diarylimidazolium salts （3） were directly synthesized starting from lH-imidazole （1） by a one-pot strategy using diaryliodonium salts as the arylating reagents, lH-Benzimidazole and 1H-1,2,4-triazole are suitable ... 详细信息

关键词： Diaryliodonium salt 1H-lmidazole Copper catalysis Diarylimidazolium saltNHC

Based on non-targeted metabolomics for differential components screening of Rosae Chinensis Flos and Rosae Rugosae Flos and their quality evaluation

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Traditional Medicine Research 2025年第2期10卷 1-15页

作者： Xu Liang Ni-Hui Zhang Zhi-Lai Zhan Guang-Lu Chang Yan gao Xia Li Wen-Yuan gao School of Pharmaceutical Science and Technology Faculty of MedicineTianjin UniversityTianjin 300193China State Key Laboratory for Quality Ensurance and Sustainable Use of Dao-di Herbs China Academy of Chinese Medical SciencesBeijing 100700China Key Laboratory of Modern Chinese Medicine Resources Research Enterprises Tianjin 300402China

Background:Rosa chinensis *** Rosa rugosa *** not only of ornamental value,but also edible flowers and the flower buds have been listed in the Chinese Pharmacopoeia as traditional *** two plants have some differences in efficacy,but the flower buds are easily confused for similar *** addition,large-scale cultivation of ornamental rose flowers may lead to a decrease in the effective components of medicinal ***,it is necessary to study the chemical composition and make quality evaluation of Rosae Chinensis Flos(Yueji)and Rosae Rugosae Flos(Meigui).Methods:In this study,40 batches of samples including Meigui and Yueji from different regions in China were collected to establish high-performance liquid chromatography ***,the fingerprints data was analyzed using principal component analysis,hierarchical cluster analysis,and partial least squares discriminant analysis analysis chemometrics to obtain information on intergroup differences,and non-targeted metabolomic techniques were applied to identify and compare chemical compositions of samples which were chosen from groups with large *** compounds were screened by orthogonal partial least-squares discriminant analysis and S-plot,and finally multi-component quantification was performed to comprehensively evaluate the quality of Yueji and ***:The similarity between the fingerprints of 40 batches roses and the reference print R was 0.73 to 0.93,indicating that there were similarities and differences between the *** principal component analysis and hierarchical cluster analysis of fingerprints data,the samples from different origins and varieties were intuitively divided into four *** least-squares discriminant analysis analysis showed that Meigui and Yueji cluster into two categories and the model was reliable.A total of 89 compounds were identified by high resolution mass spectrometry,mainly were flavonoids and flavon

关键词： Rosa chinensis Jacq. Rosa rugosa Thunb. metabolomics chemometrics multiple component quantification quality evaluation

海外学者视角下的中国乡村振兴战略:实施动因与成效

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西北农林科技大学学报（社会科学版） 2025年第1期25卷 44-52页

作者：高小升高嘉悦西北农林科技大学中国化马克思主义海外传播研究中心陕西杨凌712100

实施乡村振兴战略是党中央作出的重大决策部署,受到海外学界的持续关注和研究。海外学者的研究具有极强的实用主义目的,重在剖析中国实施乡村振兴战略的动因,评估乡村振兴战略的实施成效以及展望乡村振兴战略的未来前景。在海外学者看来... 详细信息

实施乡村振兴战略是党中央作出的重大决策部署,受到海外学界的持续关注和研究。海外学者的研究具有极强的实用主义目的,重在剖析中国实施乡村振兴战略的动因,评估乡村振兴战略的实施成效以及展望乡村振兴战略的未来前景。在海外学者看来,新时代中国共产党的使命担当、重塑中国城乡关系和应对复杂多变的国际形势是中国实施乡村振兴战略的主要原因。中国乡村振兴战略的实施不仅提振了新时代中国经济的发展,推动了新时代中国社会的伟大变革,而且极大地助推了新时代中国的文化传承。归因于世界农业发展的日益数字化趋势等因素,中国乡村振兴战略的未来发展有着前所未有的机遇,但也需要解决推进乡村振兴过程中产生的环境问题,需要平衡如土地用途调整与保障粮食安全的关系。总体来看,海外学者对中国乡村振兴战略的认知以肯定为主,并且从国内和国际两个层面提出了进一步推进乡村振兴战略的建议。然而受多种因素的影响,海外学者对乡村振兴战略实施过程中出台的部分政策的意图仍存在一定的误解和错误认知,需要在对外传播中主动予以回应、批驳和积极引导。

关键词：海外学者乡村振兴战略提出动因实施成效

Paleoclimate evolution and aridification mechanism of the eastern Tethys during the Callovian–Oxfordian: evidence from geochemical records of the Qiangtang Basin, Tibetan Plateau

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Acta Geochimica 2021年第2期40卷 199-211页

作者： Yongyao Zeng lei gao Wenqing Zhao Lanzhou Resources and Environment Voc-Tech College Lanzhou 730000China

Global climate during the Jurassic has been commonly described as a uniform greenhouse climate for a long ***,the climate scenario of a cool episode during the Callovian-Oxfordian transition following by a warming trend during the Oxfordian(163.53 to157.4 Ma)is documented in many localities of the western *** is still unclear if a correlatable climate scenario also occurred in the eastern Tethys during the same time *** this study,a detailed geochemical analysis on the 1060 m thick successions(the Xiali and Suowa formations)from the Yanshiping section of the Qiangtang Basin,located in the eastern Tethys margin during the Callovian-Oxfordian periods,was *** reveal the climate evolution of the basin,carbonate content and soluble salt concentrations(SO_(4)^(2-),Cl^(-))were chosen as climatic *** results show that the overall climate patterns during the deposition of the Xiali and Suowa formations can be divided into three stages:relatively humid(164.0 to 160.9 Ma),dry(160.9 to159.6 Ma),semi-dry(159.6 to 156.8 Ma).A similar warming climate scenario also occurred in eastern Tethys during the Callovian-Oxfordian transition(160.9 to159.6 Ma).Besides,we clarify that the Jurassic True polar wander(TPW),the motion of the lithosphere and mantle with respect to Earth’s spin axis,inducing climatic shifts were responsible for the aridification of the Qiangtang Basin during the Callovian-Oxfordian transition with a review of the paleolatitude of the Xiali formation(19.7+2.8/-2.6°N)and the Suowa formation(20.7+4.1/-3.7°N).It is because the TPW rotations shifted the East Asia blocks(the North and South China,Qiangtang,and Qaidam blocks)from the humid zone to the tropical/subtropical arid zone and triggered the remarkable aridification during the Middle-Late Jurassic(ca.165-155 Ma).

关键词： Qiangtang basin The Callovian–Oxfordian Geochemistry Paleolatitude Paleoclimate

An over review of desertification in Xinjiang,Northwest China

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Journal of Arid Land 2022年第11期14卷 1181-1195页

作者： YU Xiang lei Jiaqiang gao Xin State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China

Desertification research in arid and semi-arid regions has always been actively *** China,the problem of desertification in Xinjiang has also received extensive *** to its unique geography,many scholars have conducted corresponding research on the desertification status of *** this paper,we comprehensively reviewed desertification in Xinjiang,and compared the underlying mechanisms of desertification and the status of desertification conditions after the implementation of ecological control *** a larger scale,desertification in Xinjiang can be divided into soil salinization inside oases and sandy desertification on the edges of *** activities are considered the main cause of desertification,but natural factors also contribute to varying *** on the mechanisms of desertification has effectively curbed the development of desertification,but unreasonable use of land resources accelerates the risk of *** desertification control,there are several key ***,desertification monitoring and the early warning of desertification expansion should be ***,monitoring and reversing soil salinization also play an important role in the interruption of desertification *** is very effective to control soil salinization through biological and chemical ***,the management of water resources is also essential,because unreasonable utilization of water resources is one of the main reasons for the expansion of desertification in *** to the unreasonable utilization of water resources,the lower reaches of the Tarim River are cut off,which leads to a series of vicious cycles,such as the deterioration of ecological environment on both sides of the river and the worsening of ***,in recent years,various desertification control projects implemented in Xinjiang according to the conditions of different regions have achieved remarkable *** future studies,resea

关键词： desertification soil salinization sandy desertification desertification control soil wind erosion human activities Tarim Basin

Meningeal lymphatic vessel crosstalk with central nervous system immune cells in aging and neurodegenerative diseases

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Neural Regeneration Research 2025年第3期20卷 763-778页

作者： Minghuang gao Xinyue Wang Shijie Su Weicheng Feng Yaona Lai Kongli Huang Dandan Cao Qi Wang Science and Technology Innovation Center Guangzhou University of Chinese MedicineGuangzhouGuangdong ProvinceChina Institute of Clinical Pharmacology Guangzhou University of Chinese MedicineGuangzhouGuangdong ProvinceChina The Sixth Affiliated Hospital Sun Yat-sen UniversityGuangzhouGuangdong ProvinceChina

Meningeal lymphatic vessels form a relationship between the nervous system and periphery, which is relevant in both health and disease. Meningeal lymphatic vessels not only play a key role in the drainage of brain metabolites but also contribute to antigen delivery and immune cell activation. The advent of novel genomic technologies has enabled rapid progress in the characterization of myeloid and lymphoid cells and their interactions with meningeal lymphatic vessels within the central nervous system. In this review, we provide an overview of the multifaceted roles of meningeal lymphatic vessels within the context of the central nervous system immune network, highlighting recent discoveries on the immunological niche provided by meningeal lymphatic vessels. Furthermore, we delve into the mechanisms of crosstalk between meningeal lymphatic vessels and immune cells in the central nervous system under both homeostatic conditions and neurodegenerative diseases, discussing how these interactions shape the pathological outcomes. Regulation of meningeal lymphatic vessel function and structure can influence lymphatic drainage, cerebrospinal fluid-borne immune modulators, and immune cell populations in aging and neurodegenerative disorders, thereby playing a key role in shaping meningeal and brain parenchyma immunity.

关键词： central nervous system meningeal lymphatic vessels immunity myeloid cells lymphatic cells neurodegenerative disease

Magnetism engineering of nanographene:An enrichment strategy by co-depositing diverse precursors on Au(111)

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Chinese Chemical Letters 2023年第1期34卷 206-210页

作者： Hui Zhang Jianchen Lu Yong Zhang lei gao Xin-jing Zhao Yuan-Zhi Tan Jinming Cai School of Pharmacy China Pharmaceutical UniversityNanjing 211198China Jiangsu Aosaikang Pharmaceutical Co. Ltd.Nanjing 211112China Key Laboratory of Modern Preparation of TCM Ministry of EducationJiangxi University of Chinese MedicineNanchang 330004China

The magnetism of nanographene is dominated by the structure of its carbon ***,the magnetism engineering of nanographene is hindered due to finite ***,we demonstrate an ingenious synthetic strategy to engineer the magnetism of nanographene through hetero-coupling two precursors on Au(111)***-resolved scanning tunneling microscopy and spectroscopy results show that two homo-coupled products host a closed-shell structure,while the products with five membered ring defects perform as an open-shell one with the total spin number of 1/2,confirmed by spin-polarized density functional theory *** two hetero precursors on Au(111)substrate,the heterocoupled products both perform as the magnetic structure with total spin quantum numbers of 1/2 and 1,resulting from carbon skeleton *** work provides an effective way to engineer the magnetism of nanographene by enriching the magnetic products simultaneous,which could be extended into other controllable magnetic nanographene instruction.

关键词： Nanographene Magnetism enrichment Co-deposition Scanning tunneling microscope

Dirichlet characters, Gauss sums and arithmetic Fourier transforms

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Applied Mathematics(A Journal of Chinese Universities) 2014年第3期29卷 307-316页

作者： gao jing LIU Hua-ning School of Mathematics and Statistics Xi’an Jiaotong University School of Mathematics Northwest University

In this paper, a general algorithm for the computation of the Fourier coefficients of 2π-periodic （continuous） functions is developed based on Dirichlet characters, Gauss sums and the generalized MSbius transform. It permits the direct extraction of the Fourier cosine and sine coefficients. Three special cases of our algorithm are presented. A VLSI architecture is presented and the error estimates are given.

关键词： Dirichlet characters Gauss sums arithmetic Fourier transforms generalized MSbius transform