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Geodesy and Geodynamics 2024年第2期15卷 189-199页

作者： Juan A.García-Armenteros center for advanced studies in Earth Sciences Energy and Environment(CEACTEMA)University of Jaén23071 JaenSpain

This paper analyzed GPS data from the Topo-Iberia network spanning almost 12 years(2008-2020).The data quality information for all 26 Topo-Iberia stations is provided for the first time,complementing the Spanish Geological Survey’s storage *** analyses based on quality indicators obtained using TEQC have been carried *** guidelines and data quality information from the IGS stations have been considered as the quality references,with the stations ALJI,EPCU,and TIOU standing out as the worst stations,while on the contrary,FUEN,PALM,PILA,and TRIA meet the quality requirements to become an IGS *** relationship between the GPS data quality and their GAMIT-and Gipsy X-derived postfit ionosphere-free phase residuals has also been investigated,and the results reveal an inversely proportional *** has been found that the stations showing an increase in elevation of the horizon line,also show an increase in cycle slips and multipath,are among the poorest quality stations,and among those with the highest postfit RMS of phase ***,the evolution of the vegetation around the antenna should be considered as it could cause a progressive loss of quality,which is not complying with the IGS *** quality assessment shows that the Topo-Iberia stations are appropriate for geodetic purposes,but permanent monitoring would be necessary to avoid the least possible loss of data and *** addition,a method to characterize the GNSS data quality is proposed.

关键词： GPS dataquality's effects IGS quality standard Postfit LC phase residual Qualityassessment Topo-Iberia CGPS network

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Toward a comprehensive hypothesis of oxygen-evolution reaction in the presence of iron and gold

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Journal of Energy Chemistry 2024年第2期89卷 172-183,I0005页

作者： Negah Hashemi Jafar Hussain Shah Cejun Hu Subhajit Nandy Pavlo Aleshkevych Sumbal Farid Keun Hwa Chae Wei Xie Taifeng Liu Junhu Wang Mohammad Mahdi Najafpour Department of Chemistry Institute for Advanced Studies in Basic Sciences(IASBS)Zanjan 45137-66731Iran center for advanced Mössbauer Spectroscopy Mössbauer Effect Data CenterDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina Key Lab of advanced Energy Materials Chemistry(Ministry of Education) Renewable Energy Conversion and Storage CenterCollege of ChemistryNankai UniversityTianjin 300071China advanced Analysis center Korea Institute of Science and TechnologySeoul 02792Republic of Korea Institute of Physics Polish Academy of SciencesWarsaw 02-668Poland National and Local Joint Engineering Research center for Applied Technology of Hybrid Nanomaterials Henan UniversityKaifeng 475004HenanChina center of Climate Change and Global Warming Institute for Advanced Studies in Basic Sciences(IASBS)Zanjan 45137-66731Iran Research center for Basic Sciences&Modern Technologies(RBST) Institute for Advanced Studies in Basic Sciences(IASBS)Zanjan 45137-66731Iran

This study investigates the effects of Fe on the oxygen-evolution reaction(OER)in the presence of *** distinct areas of OER were identified:the first associated with Fe sites at low overpotential(~330 mV),and the second with Au sites at high overpotential(~870 mV).Various factors such as surface Fe concentration,electrochemical method,scan rate,potential range,concentration,method of adding K_(2)Fe O_(4),nature of Fe,and temperature were varied to observe diverse behaviors during OER for Fe O_(x)H_(y)/*** amounts of Fe ions had a significant impact on OER,reaching a saturation point where the activity did not increase *** electronic interaction between Fe and Au ions was indicated by X-ray photoelectron spectroscopy(XPS)and electron paramagnetic resonance(EPR)*** situ visible spectroscopy confirmed the formation of Fe O_(4)^(2-)during *** situ Mossbauer and surfaceenhanced Raman spectroscopy(SERS)analyses suggest the involvement of Fe-based species as intermediates during the rate-determining step of OER.A lattice OER mechanism based on Fe O_(x)H_(y)was proposed for operation at low *** functional theory(DFT)calculations revealed that Fe oxide,Fe-oxide clusters,and Fe doping on the Au foil exhibited different activities and stabilities during *** study provides insights into the interplay between Fe and Au in OER,advancing the understanding of OER mechanisms and offering implications for the design of efficient electrocatalytic systems.

关键词： DFT calculation Fe/Au electrocatalysis Mechanism Oxygen evolution Water oxidation

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AI enhances drug discovery and development

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National Science Review 2024年第3期11卷 52-54页

作者： Fang Bai Shiliang Li Honglin Li Shanghai Institute for advanced Immunochemical studies and School of Life Science and Technology ShanghaiTech University Lingang Laboratory Innovation center for AI and Drug Discovery East China Normal University

The advent of the third wave of artificial intelligence(AI) heralds a new era in drug discovery. AI-powered techniques can be characteristic of identifying features that are difficult for humans to interpret from big ...

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Realizing quantum imaginary time evolution in experiment

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 167-168页

作者： Xiao Yuan center on Frontiers of Computing studies Peking UniversityBeijing 100871China School of computer Science Peking UniversityBeijing 100871China

NISQ,or Noisy Intermediate-Scale Quantum computing,represents a pivotal and the state-of-the-art quantum technology[1].Characterized by intermediate-scale quantum devices that are beyond classical computational capabilities yet fall short of the error-correction thresholds required for fault-tolerant quantum computing,NISQ devices exhibit both promise and *** devices hold immense potential in solving certain computational problems that surpass classical capabilities,with wide applications in optimization,machine learning,and quantum chemistry.

关键词： quantum imaginary correction

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Synthesis of Organofluorine Compounds with Acylsilanes

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Chinese Journal of Chemistry 2024年第8期42卷 887-902页

作者： Youyuan Guo Gang Zhou Xiao Shen The Institute for advanced studies Engineering Research Center of Organosilicon Compounds&MaterialsMinistry of EducationWuhan University299 Bayi RoadWuhanHubei430072 China

Comprehensive Summary,Organofluorine compounds are central in synthetic chemistry,medicinal chemistry and material *** this review,we summarize the investigations on the synthesis of organofluorine compounds with *** the non-fluorinated acylsilanes,the in situ generation of difluoroenoxysilanes from the reactions of the acylsilanes with trifluoromethylation reagents is the major pathway,leading to the facile preparation of variousα,α-*** the fluoroalkylacylsilanes,apart from the in situ generation of difluoroenoxysilanes through anion Brook rearrangement,radical Brook rearrangement of the photoexcited acylsilanes and the selective control of reactivities of the biradicals pave the way for the synthesis of a variety of organofluorine *** general,most of these reactions gave racemic products,and the asymmetric synthesis of organofluorine compounds with acylsilanes is still rare,which would be a future.

关键词： Acylsilanes Organofluorine compounds Brook rearrangement Radical rearrangement β-Fluoride elimination Asymmetric catalysis Photocatalysis Defluoroalkylation

Reproductive patterns in Araucaria araucana forests in the Andean range, Chile

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Ecological Processes 2024年第01期13卷 252-261页

作者： Sergio Donoso Karen Pe?a-Rojas Claudia Espinoza Carolain Badaracco Rómulo Santelices-Moya Antonio Cabrera-Ariza Mediterranean Forests Laboratory Faculty of Forestry and Nature Conservation Centro Secano Faculty of Agricultural and Forestry Sciences Universidad Católica del Maule Maule advanced studies Research center Vice-Rector's Office for Research and Postgraduate Studies Catholic University of Maule

Background Araucaria araucana is a mast species that presents a high variability in annual cone production. Researchers have recorded synchronization events in cone production in different populations, which allows the seed production to be concentrated, reducing the percentage of seeds consumed by different animal *** We sampled three populations located in the Andes Mountains, Araucanía Region, Chile. In 2004 we began the collection of data on cone production, for which we installed permanent plots（1200 m2each） at each location. We identified and labeled each female tree in each plot to monitor its cone production. In 2012 we selected a total of 30 trees near the plots to evaluate the number of seeds per cone. In each February from 2012 to 2014 we selected two mature cones and covered them with a porous mesh for subsequent collection and storage in March. At the beginning of June, we counted and weighed the seeds, determining the average weight, the number of seeds per cone, the germination capacity（GC）, and the germination speed（GS）.Results Cone production was synchronous across the three locations. We observed significant differences among the locations and years evaluated. The cones had fewer seeds in 2013（high production） compared to those in 2012（low production）, but their weights were similar. In 2014 the cones produced smaller seeds in fewer quantities. The difference between the years 2013 and 2014 resulted from the high-energy expenditure in 2013. Regarding GC and GS, there were significant differences among the three locations（GC: F = 45.41, p < 0.01; GS: F = 96.08, p < 0.01）, where the highest values were observed in *** Both GC and GS are related to seed weight but not to the number of cones produced in a given year. These annual fluctuations in seed production are determining factors in the population dynamics of forest species. Our results allow a better understanding of the reproductive phenology of A. araucana and could hel

关键词： Seed weight Germination potential Masting species Sustainable use Dioecious species

Cryptanalysis of DBST, a lightweight block cipher

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Frontiers of computer Science 2024年第4期18卷 219-221页

作者： Sadegh SADEGHI Nasour BAGHERI Department of Mathematics Institute for Advanced Studies in Basic Sciences(IASBS)Zanjan 45137-66731Iran Research center for Basic Sciences and Modern Technologies(RBST) Institute for Advanced Studies in Basic Sciences(IASBS)Zanjan 45137-66731Iran Electrical Engineering Department Shahid Rajaee Teacher Training UniversityTehran 16788-15811Iran School of computer Science(SCS) Institute for Research in Fundamental Sciences(IPM)Tehran 19395-5531Iran

1 Introduction Conventional cryptographic primitives are not suitable for resource-constrained ***,numerous lightweight primitives have been proposed over the past decade,specifically tailored for such ***,such ciphers would not be used in a real-world application unless they were thoroughly tested for security against existing *** this direction,DBST[1]cipher has been recently proposed by Yan et *** balance security,cost,and efficiency,DBST has implemented a novel 4-branch generalized Feistel variant *** this structure,a 2-branch XOR operation has been incorporated in the middle section,establishing interconnections between all *** the other hand,by leveraging the bit-slice technique and subkeys,the algorithm introduces an innovative approach to constructing a dynamic S-box *** designers of DBST cipher have extensively investigated its resistance to known attacks such as linear and differential cryptanalysis,as well as impossible differential cryptanalysis,among *** them,the objective of differential cryptanalysis[2]is to identify high-probability characteristics in the plaintext that are transmitted to the ciphertext,known as distinguishers.

关键词： structure. primitive branch

Tuning the ferroelectricity of Hf0.5Zr0.5O2 with alloy electrodes

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Science China(Information Sciences) 2024年第8期67卷 321-330页

作者： Keqin LIU Bingjie DANG Zhiyu YANG Teng ZHANG Zhen YANG Jinxuan BAI Zelun PAN Ru HUANG Yuchao YANG Beijing advanced Innovation center for Integrated Circuits School of Integrated Circuits Peking University School of Electronic and computer Engineering Peking University center for Brain Inspired Chips Institute for Artificial Intelligence Peking University center for Brain Inspired Intelligence Chinese Institute for Brain ResearchBeijing

Tuning ferroelectricity of Hf0.5Zr0.5O2is crucial for facilitating its practical applications in various fields, including in-memory and neuromorphic computing. Previous studies have revealed that the electrodes have a significant influence on ferroelectricity, and changing electrode materials can realize different but discrete ferroelectric polarization values. Here, we introduce an alloy-electrode method, in order to achieve gradual and accurate modulation of ferroelectric polarization, especially useful for matching the polarization charges at the interface of ferroelectric insulators and ferroelectric semiconductors. Au and W electrodes are chosen as baselines for realizing weak and strong ferroelectric polarization, where the intermediate states can be achieved by adjusting the ratio of metals in the Au-W alloy. To demonstrate the generality of this approach, the Cu-W alloy electrode is also realized for tuning ferroelectric polarization. The effect of alloy electrodes on device leakage current, endurance, and retention is evaluated. In addition, the temperature stability of ferroelectric capacitors is tested, where limited changes in both remnant polarization and coercive voltages are observed, showing the great potential of the ferroelectric hafnium oxide. Such gradual modulation of ferroelectric polarization could facilitate the application of Hf0.5Zr0.5O2in in-memory and neuromorphic computing.

关键词： ferroelectric hafnium oxide alloy electrode gradual modulation temperature stability

A head-mounted photoacoustic fiberscope for hemodynamic imaging in mobile mice

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Light(Science & Applications) 2024年第6期13卷 1012-1014页

作者： Xiaoyan Zheng Shuai Na National Biomedical Imaging center College of Future TechnologyPeking UniversityBeijing100871China Academy for advanced Interdisciplinary studies Peking UniversityBeijing100871China

A miniaturized photoacoustic fiberscope has been developed, featuring a lateral resolution of 9 microns and a lightweight design at 4.5 grams. Engineered to capture hemodynamic processes at single-blood-vessel resolution at a rate of 0.2 Hz, this device represents an advancement in head-mounted tools for exploring intricate brain activities in mobile animals.

关键词： fiber mobile Engine

Investigation of operation and degradation mechanisms in ZnTeSe blue quantum-dot light-emitting diodes by identifying recombination zone

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Nano Research 2024年第7期17卷 6527-6533页

作者： Oul Cho Sujin Park Hogeun Chang Jiwhan Kim Jaekwon Kim Sungwoo Kim Taehyung Kim Jeonghun Kwak Department of Electrical and computer Engineering Inter-university Semiconductor Research Centerand Soft Foundry InstituteSeoul National UniversitySeoul 08826Republic of Korea Material Research center Samsung Advanced Institute of TechnologySuwonGyeonggi-do 16419Republic of Korea

ZnTeSe quantum dots(QDs),recognized as promising eco-friendly blue electroluminescent emitters,remain under-explored in light-emitting diode(LED)***,to elucidate the operation and degradation mechanisms of ZnTeSe blue QD-LEDs,stacked ZnTeSe QD layers with discernable luminescence are designed by varying Te doping concentrations,and the recombination zones(RZs)of the blue QD-LEDs are *** RZs are identified near the hole-transport layer(HTL),confirmed by angular-dependent electroluminescence measurements and optical *** addition,in order to investigate carrier dynamics in the process of recombination,the transient electroluminescence(tr-EL)signals of the dichromatic QD-LEDs are *** a result,it is inferred that the RZ initially formed near the electron-transport layer(ETL)due to the high injection barriers of ***,due to the fast electron mobility,the RZ shifts toward the HTL as the operating current *** the device lifetime tests,the RZ remains stationary while the photoluminescence(PL)corresponding to the RZ undergoes a substantial decrease,indicating that the degradation is accelerated by the concentrated *** this study contributes to a deeper understanding of the operational mechanisms of ZnTeSe blue QD-LEDs.

关键词： quantum dots light-emitting diodes degradation recombination zones carrier dynamics