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Pre-Devonian tectonic evolution of the eastern South China Block:Geochronological evidence from detrital zircons

Science China Earth Sciences 2010年第10期53卷 1427-1444页

作者： lei xiang LiangShu Shu Nanjing Univ Sch Earth Sci & Engn State Key Lab Mineral Deposits Res Nanjing 210093 Peoples R China

Using the U-Pb LA-ICP-MS analysis technique we analyzed geochronological features of detrital zircons from Devonian and Ordovician coarse sandstone in southern Jiangxi Province,northern Cathaysia *** ancient crustal information was *** 350 groups of U-Pb age center on five ranges:2600-2300 Ma(peak at 2470 Ma),1100-900 Ma(peak at 980 Ma),900-700 Ma(peak at 800 Ma),650-520 Ma(peak at 600 Ma) and 450-400 Ma(peak at 440 Ma).We also found a detrital zircon of ~3.5 *** is the oldest age in northern Cathaysia Block obtained so *** the analysis we concluded that:(1) the 2600-2300 Ma period,characterized by a global continent-building,records late Neoarchean magmatism that did not occur in the neighboring area of Cathaysia;(2) the marked peak at 1100-900 Ma corresponds with the assembly time of the Neoproterozoic supercontinent,Rodinia,suggesting that the Cathaysia Block was once a part of Rodinia,and numerous euhedral zircons with similar ages likely resulted from the Grenville event;(3) the peak at 900-700 Ma corresponds to the breakup of Rodinia,as evidenced by wide occurrence of Neoproterozoic granite,basic dyke swarms and continental rift-type deposition;(4) the 650-520 Ma period is the typical time of the Pan-African event,but as yet no associated magmatic rock has been reported in this area;and(5) the peak at 450-400 Ma,representing the early Paleozoic orogeny,was recorded in various igneous *** Silurian-Lower Devonian granitic plutons,orthogneisses and their zircon U-Pb dating ages(450-400 Ma) are important evidence of an early Paleozoic orogenic *** data support the interpretation of an Early Paleozoic tectonic heat event in Cathaysia,which was likely to be caused by intracontinental collision.

关键词： detrital zircon U-Pb dating tectonic evolution pre-Devonian South China

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Adaptive Simplified Chicken Swarm Optimization Based on Inverted S-Shaped Inertia Weight

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Chinese Journal of Electronics 2022年第2期31卷 367-386页

作者： GU Yanchun LU Haiyan xiang lei SHEN Wanqiang School of Science Jiangnan University Wuxi Engineering Technology Research Center for Biological Computing Jiangnan University

Considering the issues of premature convergence and low solution accuracy in solving high-dimensional problems with the basic chicken swarm optimization algorithm, an adaptive simplified chicken swarm optimization algorithm based on inverted S-shaped inertia weight(ASCSO-S) is proposed. Firstly, a simplified chicken swarm optimization algorithm is presented by removing all the chicks from the chicken swarm. Secondly, an inverted S-shaped inertia weight is designed and introduced into the updating process of the roosters and hens to dynamically adjust their moving step size and thus to improve the convergence speed and solution accuracy of the algorithm. Thirdly, in order to enhance the exploration ability of the algorithm, an adaptive updating strategy is added to the updating process of the *** experiments on 21 classical test functions show that ASCSO-S is superior to the other comparison algorithms in terms of convergence speed, solution accuracy, and solution stability. In addition, ASCSO-S is applied to the parameter estimation of Richards model, and the test results indicate that ASCSO-S has the best fitting results compared with other three algorithms.

关键词： particle swarm optimisation solution stability adaptive simplified chicken swarm optimization algorithm parameter estimation Richards model solution accuracy swarm intelligence inverted S-shaped inertia weight convergence speed adaptive updating strategy convergence updating process ASCSO-S

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Feature-Grounded Single-Stage Text-to-Image Generation

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Tsinghua Science and Technology 2024年第2期29卷 469-480页

作者： Yuan Zhou Peng Wang lei xiang Haofeng Zhang School of Artificial Intelligence Nanjing University of Information Science and TechnologyNanjing 210044China School of Computer Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China

Recently,Generative Adversarial Networks(GANs)have become the mainstream text-to-image(T2I)***,a standard normal distribution noise of inputs cannot provide sufficient information to synthesize an image that approaches the ground-truth image ***,the multistage generation strategy results in complex T2I ***,this study proposes a novel feature-grounded single-stage T2I model,which considers the“real”distribution learned from training images as one input and introduces a worst-case-optimized similarity measure into the loss function to enhance the model's generation *** results on two benchmark datasets demonstrate the competitive performance of the proposed model in terms of the Frechet inception distance and inception score compared to those of some classical and state-of-the-art models,showing the improved similarities among the generated image,text,and ground truth.

关键词： text-to-image(T2I) feature-grounded single-stage generation Generative Adversarial Network(GAN)

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Detection of spheriodal free oscillation excited by Peru 8.2 M_(s) earthquake with five international superconducting gravimeter data

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Science China Earth Sciences 2005年第1期48卷 123-133页

作者： lei xiang'e XU Houze SUN Heping Key Laboratory of Dynamic Geodesy Institute of Geodesy and Geophysics. Chinese Academy of Sciences Wuhan 430077 China Key Laboratory of Dynamic Geodesy Institute of Geodesy and Geophysics. Chinese Academy of Sciences Wuhan 430077 China Key Laboratory of Dynamic Geodesy Institute of Geodesy and Geophysics. Chinese Academy of Sciences Wuhan 430077 China

In this paper, authors obtain the spectral peaks of the earth free oscillation and check all normal modes from 0S0 to 0S48 accurately, with the Fourier analysis and the maximum entropy spectrum method dealing jointly with six groups of the observational residual data from five international superconducting gravimeter stations. By comparing the observational results in this paper with three former groups of observations or models, authors notice an extra discrepancy between two observational 0S2 modes excited separately by Peru earthquake and Alaska earthquake, which probably mirrors the anisotropy of the Earth's inner core. The analysis on the splitting 1S2 mode shows that the asymmetric factor of rotationwise spectral splitting is possible to be different from that of anti-rotationwise spectral splitting.

关键词： 8.2 Ms Peru earthquake, detection of Earth free oscillation, observation of superconducting gravimeter,anisotropy of earth's inner core.

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Advancements and challenges in bionic joint lubrication biomaterials for sports medicine

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Biosurface and Biotribology 2024年第3期10卷 89-105页

作者： lei xiang Zhen Wang Wenguo Cui Department of Orthopaedics Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint DiseasesShanghai Institute of Traumatology and OrthopaedicsRuijin HospitalShanghai Jiao Tong University School of MedicineShanghaiChina

Bionic lubricant materials are a class of materials inspired by natural organisms and offer excellent lubrication properties and *** the field of sports medicine,their application opens up new possibilities for the prevention and treatment of sports-related *** authors will introduce the existing theoretical models of friction in the locomotor system,the characteristics and advantages of biomimetic lubrication materials and discuss in depth their applications in the field of sports *** development of bionic lubrication materials opens up unprecedented opportunities for sports medicine to provide more effective and long-lasting treatment options for patients.

关键词： biointerface bio-lubricant biomaterials biomedical application medicine

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Pd-catalyzed ortho-olefination of aromatic acetyl esters

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Chinese Chemical Letters 2017年第3期28卷 517-520页

作者： lei xiang Kai Yang Qiu-Ling Song Institute of Next Generation Matter Transformation College of Chemical Engineering at Huaqiao University Institute of Pharmacy and Pharmacology Learning Key Laboratory for Pharmacoproteomics University of South China

A Pd（Ⅱ）-catalyzed ortho-olefination of aromatic acetic esters is described which features with an excellent funcitional group tolerance, good yields, mild reaction conditions, good scalability as well as high chemo... 详细信息

关键词： ortho-Olefination Aromatic acetyl ester Pd catalyst C–H activation Weak coordination

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Recent advances of allenes in the first-row transition metals catalyzed C-H activation reactions

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Chinese Chemical Letters 2019年第8期30卷 1495-1502页

作者： xiang-lei Han Peng-Peng Lin Qingjiang Li School of Pharmaceutical Sciences Sun Yat-sen UniversityGuangzhou 510006China State Key Laboratory of Natural and Biomimetic Drugs Peking UniversityBeijing 100191China

Transition-metal-catalyzed C–H activation reaction has proven to be a powerful and efficient tool for the formation of diverse C-C and C–X bond and construction of functional complex *** the viewpoint of sustainable chemistry,the first-row transition metals,such as Mn,Fe,Co,Ni and Cu,have been recognized as cheap,environmentally friendly and reactively effective catalysts for a number of C-H functionalization ***,compared with the commonly used alkenes and alkynes in the first-row transition-metal-catalyzed C–H activations,considerable achievements have just been made by the use of structurally unique and reactively rich allenes as coupling partners in recent *** review summarizes the recent progress of the first-row transition-metal-catalyzed C–H activations with allenes.

关键词： Allene C-H functionalization First-row transition metal Annulation Regioselectivity

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Fast and abundant in vitro spontaneous haustorium formation in root hemiparasitic plant Pedicularis kansuensis Maxim. (Orobanchaceae)

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Plant Diversity 2018年第5期40卷 226-231页

作者： lei xiang Yanmei Li Xiaolin Sui Airong Li Yunnan Key Laboratory for Wild Plant Resources Department of Economic Plants and Biotechnology Kunming Institute of Botany Chinese Academy of Sciences Kunming 650201 China University of Chinese Academy of Sciences 19A Yuquan Road Beijing 100049 China

Haustorium formation is the characteristic feature of all parasitic plants and a vital process for successful *** investigations on haustorium initiation and development are constricted to induced processes by host-derived signals or synthetic *** haustorium formation in the absence of host signals,a process representing an early stage in the evolution of parasitic plants,remains largely *** of fast and frequent formation of spontaneous haustoria greatly hinders full understanding of haustorium formation in root *** this study,seedlings of Pedicularis kansuensis Maxim.,a facultative root hemiparasitic species in Orobanchaceae observed to produce many spontaneous haustoria,were grown in autoclaved water agar in the absence of any known haustoriuminducing *** aimed to test the temporal and developmental pattern of spontaneous haustorium ***,effects of sucrose supply and root contact on spontaneous haustorium formation were *** haustoria were observed starting from six days after germination,much earlier than previously reported root hemiparasites.A majority of the spontaneous haustoria formed on lateral *** of seedlings with spontaneous haustoria was 28.8% when grown on water agar plates,with a mean of four haustoria per seedling two weeks after *** formation by seedlings grown in water agar amended with 2% sucrose was more than twice of those without sucrose *** grown seedlings were able to develop spontaneous haustoria at similar levels as those grown with another conspecific *** view of the fast and abundant formation of spontaneous haustoria,*** may be developed as an excellent experimental system in future investigations for unraveling endogenous regulation of haustorium initiation and development in root hemiparasitic plants.

关键词： Spontaneous haustoria Root hemiparasitic plants Orobanchaceae Pedicularis Sucrose amendment

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Structure of Pro_4H^＋ investigated by infrared photodissociation(IRPD) spectroscopy and theoretical calculations

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Chinese Chemical Letters 2016年第4期27卷 593-596页

作者： Ru-Xia Feng lei Mu Shu-Mei Yang xiang-lei Kong The State Key Laboratory of Elemento-organic Chemistry Nankai University Tianjin 300071 China Collaborative Innovation Center of Chemical Science and Engineering Nankai University Tianjin 300071 China

Combining with electrospray ionization（ESI）mass spectrometry,infrared photodissociation（IRPD）spectroscopy is a powerful method to study structures of cluster ions in the gas *** this paper,infrared photodissociation spectrum of Pro_4H~＋in the range of 2700–3600 cm 1was obtained *** theoretically predicted spectra of the two most stable isomers of Pro4^（-1） and Pro4^（-2） obtained at the level of M062X/6-31＋G（d,p）are in good consistent with the experimental *** two isomers have similar structures and close *** of them only consist of zwitterionic units,indicating the strong salt-bridged interactions inside the *** the calculated collision cross section（ccs）of Pro4-1 is found to be very close to the experimental result previously reported.

关键词： IRPD spectroscopy Proline tetramer Theoretical calculations Structure FT ICR MS

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Impacts of climate change on the potential forest productivity based on a climate-driven biophysical model in northeastern China

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Journal of Forestry Research 2020年第6期31卷 2273-2286页

作者： Wen-Qiang Gao xiang-Dong lei Li-Yong Fu Institute of Forest Resource Information Techniques Chinese Academy of ForestryKey Laboratory of Forest Management and Growth ModellingState Forestry and Grassland AdministrationBeijing 100091People’s Republic of China

Climate warming is expected to influence forest growth,composition and ***,accurately estimating and predicting forest biomass,potential productivity or forest growth is still a challenge for forest managers dealing with land-use at the stand to regional *** the present study,we predicted the potential productivity(PP)of forest under current and future climate scenarios(RCP2.6,RCP4.5,RCP6.0 and RCP8.5)in Jilin province,northeastern China by using Paterson’s Climate Vegetation and Productivity(CVP)index *** PP was validated by comparing it with the mean and maximum net primary production calculated from light energy utilization(GLM_PEM).Our results indicated that using the CVP index model is partially valid for predicting the potential forest productivity in northeastern *** exhibited obvious spatial heterogeneity varying from 4.6 to 8.9 m3 ha-1 year-1 with an increasing tendency from northwest to southeast driven by the precipitation across the *** number of vegetation-active months,precipitation and insolation coefficient were identified as the primary factors affecting PP,but no significant relationship was found for warmest temperature or temperature *** future climate scenarios,PP across the Jilin Province is expected to increase from 1.38%(RCP2.6 in 2050)to 15.30%(RCP8.5 in 2070),especially in the eastern Songnen Plain(SE)for the RCP8.5 scenarios.

关键词： Climate vegetation and productivity index Potential productivity Climate change

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