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The discovery of Late Triassic hypabyssal mafic dykes in the Huozhou complex and their geological significance:Evidence from petrology,geochemistry,and geochronology

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Acta Geochimica 2024年第6期43卷 1013-1036页

作者： Haiyan liu chong Peng College of Geographical Sciences Shanxi Normal UniversityTaiyuan 030031China Key Laboratory of Deep-Earth Dynamics of Ministry of Natural Resources Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China School of GeoSciences University of EdinburghEdinburgh EH93JWUK

The Huozhou complex in the Trans-North China Orogen exhibits two events of mafic magmatism(separated by ca.700 Ma):Neoproterozoic(920±15 Ma)Shimenyu diabase and Late Triassic(217±2.5 Ma)Xingtangsi *** have focused on systematic petrology,zircon U-Pb dating,Lu-Hf isotopes,and *** research findings indicate that the Late Triassic Xingtangsi diabase of the Huozhou complex can be classified as a transitional type between intermediate and mafic rocks based on their SiO_(2)*** classification is supported by an average SiO_(2)content of 53.94%,ranging from 53.33%to 54.28%.In the Zr/TiO_(2)*** diagram,all samples lie within the range of *** zircons from the Late Triassic Xingtangsi diabase have lowε_(Hf)(t)values ranging from-12.7 to-8.7,with an average ***,the single-stage model age T_(DM1)is estimated to be between 1207 and 1701 *** findings suggest that the magma responsible for the dyke originated from either partial melting or an enriched mantle source inside the Meso-Proterozoic lithospheric *** elevated concentrations of Th(thorium)and LREEs(light rare earth elements),as well as the Th/Yb and Th/Nb ratios,suggest the potential incorporation of subducted sediments within the magma source *** rock displays negative Nb,Ta,Zr,Hf,and Ti *** geochemical attributes align with the distinctive traits observed in volcanic rocks found within island *** formation of the Late Triassic Xingtangsi diabase is likely associated with the geological context of an arc setting,which arises from the collision between the Yangtze plate and the North China Craton.

关键词： Trans-North China Orogen Huozhou complex Geochemistry Hf isotope North China Craton

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基于自适应续流比的混合式步进电机转矩脉动抑制方法

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陕西科技大学学报 2025年第1期43卷 142-151,202页

作者：王焜刘宝泉刘艺张浩铭刘俊陕西科技大学电气与控制工程学院陕西西安710021 西安西电高压开关有限责任公司陕西西安710018

混合式步进电机细分驱动存在较大的电流纹波,导致转矩脉动明显.通过分析H桥驱动电路的续流过程,提出一种基于自适应续流比的混合式步进电机转矩脉动抑制方法.该方法利用环型分配器产生的细分指令电流i ref与实际电流i相比较,以区分当前... 详细信息

混合式步进电机细分驱动存在较大的电流纹波,导致转矩脉动明显.通过分析H桥驱动电路的续流过程,提出一种基于自适应续流比的混合式步进电机转矩脉动抑制方法.该方法利用环型分配器产生的细分指令电流i ref与实际电流i相比较,以区分当前时刻所需的续流模式.在快速续流模式下,实时监测电流指令与实际电流的差值Δi ref,通过自适应系数k动态调节续流时间,直至电机相电流快速下降至给定电流i ref后切换至缓慢续流模式.对续流时长与快速续流占总续流时间的比例自适应调节以适应不同工况下步进电机的平稳运行,有效降低了转矩脉动.最后,搭建MATLAB/Simulink仿真平台并进行实验验证,结果表明,与传统混合续流控制相比,所提方法能够有效减小步进电机的转矩脉动.

关键词：混合式步进电机自适应续流比电流纹波转矩脉动

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5G Ultra-Dense Network Fingerprint Positioning Method Based on Matrix Completion

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China Communications 2023年第3期20卷 105-118页

作者： Yuexia Zhang chong liu Key Laboratory of Information and Communication Systems Ministry of Information IndustryBeijing Information Science and Technology UniversityBeijing 100101China Key Laboratory of Modern Measurement and Control Technology Ministry of EducationBeijing Information Science and Technology UniversityBeijing 100101China

The problem of high-precision indoor positioning in the 5G era has attracted more and more attention.A fingerprint location method based on matrix completion(MC-FPL)is proposed for 5G ultradense networks to overcome the high costs of traditional fingerprint database construction and matching ***,a partial fingerprint database constructed and the accelerated proximal gradient algorithm is used to fill the partial fingerprint database to construct a full fingerprint ***,a fingerprint database division method based on the strongest received signal strength indicator is proposed,which divides the original fingerprint database into several sub-fingerprint ***,a classification weighted K-nearest neighbor fingerprint matching algorithm is *** estimated coordinates of the point to be located can be obtained by fingerprint matching in a sub-fingerprint *** simulation results show that the MC-FPL algorithm can reduce the complexity of database construction and fingerprint matching and has higher positioning accuracy compared with the traditional fingerprint algorithm.

关键词： indoor positioning fingerprint matching matrix completion 5G UDN RSSI

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2.7-Ga-old mafic dike in the Trans-North China Orogen of the North China Craton and its tectonic significance

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Acta Geochimica 2023年第6期42卷 1124-1129页

We studied an Archean mafic dike in the TransNorth China Orogen of the North China Craton, which has a magmatic age of 2701 ± 83 Ma and is currently the oldest mafic dike in the North China Craton. Such an old dike is extremely rare in the world. The presence of mafic dikes indicates that the North China Craton was in a tensional tectonic environment at 2.7 Ga. Geochemical characteristics reveal that this mafic dike belongs to continental tholeiitic basalt. Results from Hf isotope analysis reveal that the mafic dike originates from a depleted mantle. The plate assembly in the North China landmass was realized during the Archean era(2.7 Ga), and a thick and stable continental crust was formed. Therefore, the first cratonization of the North China Craton was completed before 2.7 Ga. The intrusion of the 2.7-Ga-old mafic dike from the deep lithospheric mantle of the continent indicates that the North China Craton has undergone a period of extensional tectonic activity. This event marks a significant extensional event that occurred after the cratonization of the North China Craton.

关键词： Archean Mafic dike Trans-North China Orogen North China Craton Hf Cratonization

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Computational protein design and structure prediction—the 2024Nobel prize in chemistry

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Science China Chemistry 2025年

作者： Peilong Lu Lei liu School of Life Sciences and Research Center for Industries of the Future Westlake University Tsinghua-Peking Joint Center for Life Sciences Ministry of Education Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology Center for Synthetic and Systems Biology Department of Chemistry Tsinghua University

The 2024 Nobel prize in chemistry recognizes groundbreaking advancements in protein science, highlighting the power of artificial intelligence (AI) to decipher and design the molecular machinery of life. Half of the prize was awarded to David Baker for the computational design of proteins; the other to Demis Hassabis and John Jumper for their AI-driven predictions of protein structures. This article briefly reviews their achievements, and discusses the opportunities and directions that their work has enabled (Figure1).

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Evolutionary investment network and the emerging energy power in Central Asia:From the perspective of cross-border mergers and acquisitions

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Journal of Geographical Sciences 2020年第11期30卷 1849-1870页

作者： HE Ze chong Zhaohui YANG Yu ZHOU Yannan liu yi Key Laboratory of Regional Sustainable Development Modeling/lnstitute of Geographic Sciences and Natural Resources Research CASBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China Institute of Strategy Research of Guangdong-Hong Kong-Macao Greater Bay Area Guangzhou 510070China Department of Human Geography and Spatial Planning Utrecht UniversityUtrecht 3584CBNetherlands Shantou University Business School Shantou 515063GuangdongChina

Central Asia is emerging as an important pole of global economic and political power,thanks to its unique location at the heart of Eurasia and its abundance in energy *** study explores the social power change in Central Asia from the perspective of cross-border mergers and acquisitions(M&A)by using the social network *** main results are as follows:(1)The complexity of the energy M&A network has significantly decreased after the financial crisis in *** the meantime,energy M&A became an important way to enhance energy power for buyer *** centrality is becoming the most significant factor affecting energy power,yet the effect of out-degree is weakening.(2)The community underwent multifaceted restructuring,which reflected the shift of energy power in Central *** is the most powerful country in the energy sector in Central *** addition,East Asian countries/regions,represented by China,are actively enhancing their energy power.(3)Different M&A modes reflect various M&A motivations of countries in the energy *** the future,more efforts should be made to promote the establishment of a pragmatic and efficient multilateral energy cooperation mechanism and strength the cooperation of the economy and energy finance when China participates in the energy market in Central Asia.

关键词： energy power mergers and acquisitions evolutionary characteristic dynamic bargaining Central Asia

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Microalloying Al alloys with Sc:a review

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Rare Metals 2020年第6期39卷 636-650页

作者： Jin-Yu Zhang yi-Han Gao chong Yang Peng Zhang Jie Kuang Gang liu Jun Sun State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049China

As a kind of important light alloys,the Al alloys exhibit mechanical properties that are closely related to the *** the main alloying elements and adjusting heat treatments are usually approaches to tune the microstructure and hence artificially control the mechanical ***,the windows for the two approaches have become quite narrow,after extensive studies in the last half of *** has become the most promising strategy to further modify the microstructure and improve the mechanical properties of Al alloys,among which the element of scandium(Sc)is especially *** this paper,the recent progresses in Al alloys microalloyed with Sc are briefly reviewed,focusing on the microstructural characterization,strengthening response,and underlying *** possible key research points are also proposed for the further development of Al alloys microalloyed with Sc and other rare earth elements.

关键词： Al alloys Microalloying effect Scandium Mechanical properties

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Multi-receptive field interaction network for shape from polarization

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Science China(Information Sciences) 2025年第1期68卷 394-395页

作者： yini PENG Rui liu Zhiyuan ZHANG Zhongyuan WANG Jiayi MA Xin TIAN Electronic Information School Wuhan University Computer Science School Wuhan University Wuhan Institute of Quantum Technology

Shape from polarization (SfP) method can use the polarization information in reflected light to estimate the surface normal of the target,which can further reconstruct the shape of the *** a simple image capture process,it can use low-cost equipment to meet a high precision imaging requirement,which can be used in remote scenes and other applications.

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The effects of exercise interventions on brain-derived neurotrophic factor levels in children and adolescents:a meta-analysis

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Neural Regeneration Research 2025年第5期20卷 1513-1520页

作者： Xueyun Shao Longfei He Yangyang liu Physical Education School Shenzhen UniversityShenzhenGuangdong ProvinceChina Shenzhen Institute of Neuroscience ShenzhenGuangdong ProvinceChina

Brain-derived neurotrophic factor is a crucial neurotrophic factor that plays a significant role in brain health. Although the vast majority of meta-analyses have confirmed that exercise interventions can increase brain-derived neurotrophic factor levels in children and adolescents, the effects of specific types of exercise on brain-derived neurotrophic factor levels are still controversial. To address this issue, we used meta-analytic methods to quantitatively evaluate, analyze, and integrate relevant studies. Our goals were to formulate general conclusions regarding the use of exercise interventions, explore the physiological mechanisms by which exercise improves brain health and cognitive ability in children and adolescents, and provide a reliable foundation for follow-up research. We used the Pub Med, Web of Science, Science Direct, Springer, Wiley Online Library, Weipu, Wanfang, and China National Knowledge Infrastructure databases to search for randomized controlled trials examining the influences of exercise interventions on brain-derived neurotrophic factor levels in children and adolescents. The extracted data were analyzed using Review Manager 5.3. According to the inclusion criteria, we assessed randomized controlled trials in which the samples were mainly children and adolescents, and the outcome indicators were measured before and after the intervention. We excluded animal experiments, studies that lacked a control group, and those that did not report quantitative results. The mean difference(MD;before versus after intervention) was used to evaluate the effect of exercise on brain-derived neurotrophic factor levels in children and adolescents. Overall, 531 participants(60 children and 471 adolescents, 10.9–16.1 years) were included from 13 randomized controlled trials. Heterogeneity was evaluated using the Q statistic and I^(2) test provided by Review Manager software. The meta-analysis showed that there was no heterogeneity among the studies(P = 0.67,

关键词： adolescents brain-derived neurotrophic factor children exercise meta-analysis randomized controlled trials

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Deep eutectic solvents for separation and purification applications in critical metal metallurgy:Recent advances and perspectives

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 1-19页

作者： Shuo Chen Shengpeng Su Yanfang Huang Bingbing liu Hu Sun Shuzhen Yang Guihong Han School of Chemical Engineering Zhengzhou UniversityZhengzhou 450001China Zhongyuan Critical Metals Laboratory Henan ProvinceZhengzhou 450001China

Solvent extraction,a separation and purification technology,is crucial in critical metal *** solvents commonly used in solvent extraction exhibit disadvantages,such as high volatility,high toxicity,and flammability,causing a spectrum of hazards to human health and environmental *** solvents have been recognized as potential alternatives to these harmful organic *** the past two decades,several neoteric solvents have been proposed,including ionic liquids(ILs)and deep eutectic solvents(DESs).DESs have gradually become the focus of green solvents owing to several advantages,namely,low toxicity,degradability,and low *** this critical review,their classification,formation mechanisms,preparation methods,characterization technologies,and special physicochemical properties based on the most recent advancements in research have been systematically ***,the major separation and purification applications of DESs in critical metal metallurgy were comprehensively ***,future opportunities and challenges of DESs were explored in the current research *** conclusion,this review provides valuable insights for improving our overall understanding of DESs,and it holds important potential for expanding separation and purification applications in critical metal metallurgy.

关键词： deep eutectic solvents preparations properties separation and purification critical metal metallurgy

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