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Early Triassic Silicic Volcanics of South china:Petrogenesis and Constraints on the Geodynamic Evolution of the Paleo-Tethys Ocean Region

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 617-629页

作者： WANG Yabo LIU Lei ZHAO Zengxia LIU Xijun HUANG wenmin Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration College of Earth SciencesGuilin University of TechnologyGuilinGuangxi 541004China Collaborative Innovation center for Exploration of Nonferrous Metal Deposits and Efficient Utilization of Resources Guilin University of TechnologyGuilinGuangxi 541004China

The only occurrence of Lower Triassic silicic volcanic rocks within the South china Block is in the Qinzhou Bay area of Guangxi ***-ICP-MS zircon U-Pb dating reveals that volcanic rocks of the Beisi and Banba formations formed between 248.8±1.6 and 246.5±1.3 Ma,coeval with peraluminous granites of the Qinzhou Bay Granitic *** studied rhyolites and dacites are characterized by high SiO_(2),K_(2)O,and Al_(2)O_(3),and low MgO,CaO,and P_(2)O_(5) contents and are classified as high-K calc-alkaline S-type rocks,with A/CNK=*** volcanic rocks are depleted in high field strength elements,e.g.,Nb,Ta,Ti,and P,and enriched in large ion lithophile elements,e.g.,Rb,K,Sr,and *** the analyzed volcanic rocks have extremely enriched zircon Hf isotopic compositions(ε_(Hf)(t)=-29.1 to-6.9),source discrimination indicators and high calculated Ti-in-zircon temperatures(798-835℃)reveal that magma derived from enriched lithospheric mantle not only provided a heat source for anatectic melting of the metasedimentary protoliths but was also an endmember component of the S-type silicic *** studied early Triassic volcanics are inferred to have formed immediately before closure of the Paleo-Tethys Ocean in this region,as the associated subduction would have generated an extensional setting in which the mantle-derived upwelling and volcanic activity occurred.

关键词： geochemistry silicic volcanic rocks mantle contribution Olenekian-Anisian Paleo-Tethys oceanic plate subduction

Near-field wideband beam training for ELAA with uniform circular array

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science china(Information sciences) 2024年第6期67卷 370-383页

作者： Yuhao CHEN Linglong dai Department of Electronic Engineering Tsinghua UniversityBeijing National Research Center for Information Science and Technology (BNRist)

Extremely large-scale antenna array(ELAA) at millimeter wave(mmWave) and Terahertz(THz)band has been considered a key technology for combating high attenuation in high-frequency bands in future6G communications. Uniform circular arrays(UCAs) have attracted much attention because of their ability to provide flat beamforming gain at all angles. To realize efficient beamforming, beam training is widely used to acquire channel state information. However, with a large antenna number, the beam training overhead in ELAA systems becomes overwhelming. Moreover, with a large bandwidth, the beam defocus effect severely degrades beam training accuracy. To address these issues, this paper proposes a frequency-dependent focusing(FDF)-based beam training scheme to realize effective beam training in near-field wideband ELAA systems with UCA. Specifically, we first analyze the FDF property of UCA, where signals at different subcarriers can simultaneously focus on different distances. Then, by exploiting the FDF property to search different distances using different subcarriers simultaneously, we design a hierarchical codebook and propose an FDFbased beam training scheme. To reveal the effectiveness of the proposed scheme, we compare its necessary beam training overhead with that of existing schemes. Finally, the simulation results demonstrate that the proposed scheme can achieve accurate beam training in near-field wideband UCA systems with a low beam training overhead.

关键词： extremely large-scale antenna array (ELAA) uniform circular array (UCA) near-field wideband beam training

Impacts of external forcing and internal variability on the North Atlantic multidecadal variations since 1950

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science china Earth sciences 2024年第8期67卷 2699-2701页

作者： Wenjian HUA Aiguo dai Key Laboratory of Meteorological Disaster Ministry of Education/Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science and TechnologyNanjing 210044China Department of Atmospheric and Environmental sciences University at AlbanyState University of New YorkAlbany 12222USA

The physical formation mechanisms of the Atlantic Multidecadal Variability(AMV)in the context of global warming have been a key research topic(Vecchi et al.,2017).The conventional view is that the AMV is mainly driven by internal dynamics within the climate system,especially in the Atlantic Ocean(Zhang et al.,2019).However,some studies suggest that decadal to multidecadal variations in North Atlantic sea surface temperature(SST)since around 1950 are related to anthropogenic and natural aerosol emissions(Otter?et al.,2010;Booth et al.,2012;Hua et al.,2019).

关键词： Atlantic decadal forcing

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Resistance index and browning mechanism of apple peel under high temperature stress

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Horticultural Plant Journal 2024年第2期10卷 305-317页

作者： Hui Wang Shuhui Zhang Zidun Wang Dongmei Li Leiyu Yan Yifeng Feng Xiaojie Liu Rongxin Chen wenmin Fan Lulong Sun Zhengyang Zhao College of Horticulture Northwest A&F UniversityYanglingShaanxi 712100China College of Horticultural science and Engineering Shandong Agricultural University State Key Laboratory of Crop BiologyTai'anShandong 271018China

Apples are one of the most important economic crops *** of global warming and an aggravation of environmental,abnormally high temperatures occur frequently in fruit-growing season and seriously affect normal fruit growth and reduce fruit quality and *** took five-year-old Ruixue’(Qinfu 1×Pink Lady;CNA20151469.1) fruits as test materials,and the ambient temperature during fruit development was *** results showed that during the fruit-growing season,especially during the rapid growth stage (July to August),the maximum daily temperature exceeded 30℃ and lasted for more than 40 *** determine the effects of high temperature stress on the apple fruit resistance,we treated expanding,veraison,and maturity-period fruits at different *** was found that the fruits of the expanding period showed strong resistance to high temperature stress,whereas during veraison and maturity,fruit resistance to high temperature stress decreased,and the fruit peel browning phenotype ***,the content of malonaldehyde (MDA),hydrogen peroxide (H_(2)O_(2)),and superoxide anion (O._(2)^(-)) in the peel gradually increased with increasing *** content of total phenols,flavanol,and flavonoids in the peel decreased substantially at 45℃.Moreover,it was found that polyphenol oxidase gene (MdPPO1) was most sensitive to high temperature stress in ***,transient and stable MdPPO1 overexpression significantly promoted peel *** transgenic materials were more sensitive to high temperatures,and browning was more severe compared to non-genetically modified organism (WT).Stable MdPPO1 knockout calli obtained via clustered regularly interspersed short palindromic repeats (CRISPR/Cas9) gene knockout technology reduced the browning phenotype,and the resultant fruits were not sensitive to the effects of high temperature ***,MdPPO1 expression may be a key factor of high temperature-related changes observed in the browni

关键词： Malus domestica Borkh High temperature stress Peel Browning MdPPO1

Exploration of Strong Metal-Support Interaction in Heterogeneous Catalysts by in situ Transmission Electron Microscopy

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Chinese Journal of Chemistry 2024年第9期42卷 1004-1008页

作者： Yongjun Jiang Sheng dai Key Laboratoryfor advanced Materials and Feringa Nobel Prize Scientist Joint Research center Institute of Fine ChemicalsSchool of Chemistry&Molecular EngineeringEast China Universityof Science and TechnologyShanghai 200237China

The phenomenon of strong metal-support interaction(SMSI)observed in supported metal catalysts,usually accompanied by the formation of the encapsulation layer on metal nanoparticles,has attracted extensive research attention due to its significance in heterogeneous ***,great progress has been made in recent years in investigating SMSI by in situ transmission electron microscopy(TEM),along with an enhanced comprehension of the underlying mechanisms governing SMSI *** emerging topic summarizes recent progress utilizing in situ TEM to study the interaction between metal and support and the relationship between the structure and performance of the supported catalyst under reaction conditions.A brief perspective about the use of in situ TEM for further study of SMSI is also presented,showing prospects in this field that will stimulate further upsurging research in promoting the catalytic efficiency of supported catalysts.

关键词： Heterogeneous catalysis In situ TEM Strong metal-support interaction Structure changes Interfaces Structural evolution

How plants sense and respond to osmotic stress

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Journal of Integrative Plant Biology 2024年第3期66卷 394-423页

作者： Bo Yu dai-Yin Chao Yang Zhao Shanghai center for Plant Stress Biology CAS Center for Excellence in Molecular Plant SciencesThe Chinese Academy of SciencesShanghai 200032China Key Laboratory of Plant Carbon Capture The Chinese Academy of SciencesShanghai 200032China National Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant SciencesInstitute of Plant Physiology and EcologyThe Chinese Academy of SciencesShanghai 200032China University of Chinese Academy of sciences Beijing 100049China

Drought is one of the most serious abiotic stresses to land *** sense and respond to drought stress to survive under water *** have studied how plants sense drought stress,or osmotic stress caused by drought,ever since Charles Darwin,and gradually obtained clues about osmotic stress sensing and signaling in *** stress is a physical stimulus that triggers many physiological changes at the cellular level,including changes in turgor,cell wall stiffness and integrity,membrane tension,and cell fluid volume,and plants may sense some of these stimuli and trigger downstream *** this review,we emphasized water potential and movements in organisms,compared putative signal inputs in cell wall-containing and cell wall-free organisms,prospected how plants sense changes in turgor,membrane tension,and cell fluid volume under osmotic stress according to advances in plants,animals,yeasts,and bacteria,summarized multilevel biochemical and physiological signal outputs,such as plasma membrane nanodomain formation,membrane water permeability,root hydrotropism,root halotropism,Casparian strip and suberin lamellae,and finally proposed a hypothesis that osmotic stress responses are likely to be a cocktail of signaling mediated by multiple *** also discussed the core scientific questions,provided perspective about the future directions in this field,and highlighted the importance of robust and smart root systems and efficient source-sink allocations for generating future high-yield stress-resistant crops and plants.

关键词： cell volume drought membrane tension osmotic stress turgor

Nb_(2)O_(5) nanocrystals decorated graphene composites as anode materials for high-performance dual-ion batteries

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Nano Research 2024年第3期17卷 1535-1541页

作者： Lei Wang Fei Huang Guoyin Zhu Zhihui dai Jiangsu Collaborative Innovation center of Biomedical Functional Materials Jiangsu Key Laboratory of Biofunctional MaterialsSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China Institute of advanced Materials and Flexible Electronics(IAMFE) School of Chemistry and Materials ScienceNanjing University of Information Science&TechnologyNanjing 210044China School of Chemistry and Molecular Engineering Nanjing Tech UniversityNanjing 211816China

Niobium oxide(Nb_(2)O_(5))is a promising material in photocatalytic,solar cell,electronic like electron field emitters,and especially lithium-ion batteries(LIBs)because of its adjustable morphologies,controllable crystal type,stable structure,and environmental ***,its low electrical conductivity lowers the rate performance and limits the practical applications in ***,we present a one-step solid-state synthesis of orthogonal Nb_(2)O_(5) nanocrystals/graphene composites(Nb_(2)O_(5)/G)as high-performance anode materials in *** from the nanoscale crystalline structure Nb_(2)O_(5) and highly-conductive graphene substrate,the as-prepared Nb_(2)O_(5)/G exhibits excellent electrochemical ***,a reversible structural phase transition between orthogonal Nb_(2)O_(5) and tetragonal Li1-xNbO_(2)(0advanced transition metal oxide/graphene composite anode and a comprehension of its electrochemical reaction mechanism.

关键词： niobium oxide graphene anode dual-ion batteries graphite intercalation

Influence of Current Density on the Photocatalytic Activity of Nd:TiO_(2) Coatings

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Journal of Wuhan University of technology(Materials science) 2024年第1期39卷 32-38页

作者：施渊吉 ZHANG Zhen dai Yunzhong LI Jingxiao CHEN Zeyu School of Mechanical Engineering Nanjing Vocational University of Industry TechnologyNanjing 210046China College of Material science and technology Nanjing University of Aeronautics and AstronauticsNanjing 210016China School of Materials science and Engineering Nanjing Institute of TechnologyNanjing 211167China Key Laboratory of Modern Agricultural Equipment and technology Jiangsu UniversityZhenjiang 212013China

The Nd:TiO_(2 )PEO coatings were formed in a phosphate-based electrolyte with the addition of Nd_(2)O_(3 )under the current density of 150,200,250 and 300 m A/cm^(2).SEM results showed that the micropores decreased on quantity and increased on scale with the increasing current *** results revealed that the roughness of the coatings increased with the increasing current *** and composition analysis showed that the Nd:TiO_(2) coatings were mainly composed of anatase and rutile *** the anatase phase content has reached the maximum value at the current density of 250 m A/cm^(2).XPS results indicated that Ti2p spin-orbit components of the Nd:TiO_(2) coatings are shifted towards higher binding energy,compared with the pure TiO_(2) coating,suggesting that some of the Nd^(3+)ions are combined with TiO_(2) lattice and led to *** test showed that the photocatalytic activity of Nd:TiO_(2) coatings varied in the same pattern with the anatase content variation in Nd:TiO_(2) *** photocatalytic experiment results show that the photocatalytic activity of Nd:TiO_(2) coatings can be greatly enhanced with moderate amount of Nd^(3+).However,excessive amount of Nd^(3+)does not have an effective impact on the photoctalytic activity improvement.

关键词： PEO current density AFM XPS Nd:TiO_(2) photocatalytic

The tail risk safe haven property of china's energy futures against US market implied volatility

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Journal of Management science and Engineering 2024年第2期9卷 271-291页

作者： Xingyu dai Peng-Fei dai Qunwei Wang Zhi-Yi Ouyang College of Economics and Management Nanjing University of Aeronautics and AstronauticsNanjing211106China Research center for Soft Energy science Nanjing University of Aeronautics and AstronauticsNanjing211106China School of Management Wuhan University of TechnologyWuhan430070China Research Institute of Digital Governance and Management Decision Innovation Wuhan University of TechnologyWuhan430070China Huafu Fund Management Co. Ltd.ShanghaiChina

This paper analyses the tail risk contagion of US market implied volatility(USIV)on china's energy futures(CEF)markets,exploring how to utilize operations in the CEF to achieve a safe *** CEF characteristics to simultaneously take both long-/short-positions and engage in long-/short-run investment horizons,this paper defines eight different CEF safe haven attributes to counteract the tail risk of extreme increases in *** trading data from March 27,2018,to October 30,2023,the empirical results show that,first,in the analysis of the entire sample period,china's coking coal futures can serve as a weak safe haven,aiding long-position investors in mitigating the tail risks associated with US gold and stock market implied *** coal futures also assist short-position investors in countering US stock market implied volatility tail ***,in the sub-period analysis,the safe haven attributes of CEF exhibit strong heterogeneity and asymmetry across different ***,the time span during which CEF exhibits a particular safe haven attribute does not persist for an extended period.

关键词： china's energy futures Safe havenImplied volatility Multi-timescale analysis Cross-quantilogram model