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Precipitation of multi-type nano-quasicrystals in a Mg-zn-Y alloy

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Journal of Magnesium and Alloys 2024年第3期12卷 997-1008页

作者： W.z.Wang X.z.zhou l.F.zhang H.Q.Ye z.Q.Yang Shenyang National laboratory for Materials Science Institute of Metal ResearchChinese Academy of ScienceShenyang 110016China Ji Hua laboratory Foshan 528251China Foshan University Foshan 528231China

Mg-6zn-1Y(at.%)ribbons with strengthening precipitates of multi-type nanoquasicrystals were prepared by melt-spinning followed by aging *** evolution of the rapidly solidified ribbons during isothermal aging was comprehensively studied using various electron microscopy *** new kinds of decagonal quasicrystals were formed in aged ribbons,in addition to precipitation of nanometer icosahedral ***-resolution observations reveal that both decagonal quasicrystals can be modeled by quasiperiodic tiling with decagonal clusters of 2.5 nm in diameter,but overlap of neighboring clusters in both decagonal quasicrystals is different from the Gummelt model observed in other quasicrystals.A shell composed of complex laves Mg-zn domains was formed surrounding each decagonal quasicrystal precipitate upon prolonged *** addition,all kinds of nanoprecipitates exhibit excellent structure and size stability at 573 *** findings may have implications for not only fundamental studies about quasicrystals,but also microstructural manipulation of high-performance Mg alloys.

关键词： Quasicrystal Mg alloys Rapid solidification Scanning-transmission electron microscopy.

Effects of Nb/Ti Ratio on the Microstructures of Two Experimental Ni-based Cast Superalloys

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Effects of Nb/Ti Ratio on the Microstructures of Two Experim...

Four late-type Galaxies with Double Radio lobes and Properties of Such Galaxies

中国材料大会2012

作者： W. Sun X.z. Qin W. Wang T.T. Wang Y.A Guo J.T. Guo l.H lou l.z. zhou Institute of Metal Research Chinese Academy of Sciences

ISBN: (纸本)9783037856086;3037856084

Effects of Nb/Ti ratio on the microstructures of two experimental Ni-based cast superalloys of the Nb/Ti ratio 0.46 and 0.03 were investigated. The Nb/Ti ratio had a significant effect on the dendritic microstructures, especially the γ′ precipitate, of the two alloys under the as-cast condition. The amount and composition of primary MC carbides were closely related to the Nb/Ti ratio for that the Nb atoms have a stronger tendency to form the MC carbides than the Ti atoms. During thermal exposure, the primary MC carbides gradually degraded through two reactions: firstly MC + γ→ M6C + γ′ and then MC + γ→ M23C6 + γ′. The Nb/Ti ratio had little influence on the reaction formation but obvious influence on the decomposition degree of the primary MC carbides decomposition. In addition, the second M6C and M23C6 carbides on the boundaries （GBs） gradually formed a continuous chain during thermal exposure. The γ′-free zones appeared along the GBs as the growth of the second carbides and γ′ precipitates on the GBs when thermal exposure time last up to 3000h.

关键词： Ni-based cast superalloy Thermal exposure Microstructural evolution Nb/Ti ratio

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Research in Astronomy and Astrophysics 2024年第4期24卷 84-90页

作者： z.S.Yuan X.Y.Gao z.l.Wen J.l.Han National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China CAS Key laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Sciences University of Chinese Academy of SciencesBeijing 100049China

The triggering mechanism for radio lobes from late-type galaxies is not fully *** samples are desired for a thorough investigation and *** util.z.ng the optical data from the newly released Dark Energy Spectroscopic Instrument imaging surveys and the radio sources from the NRAO VlA Sky Survey and the Faint Images of the Radio Sky at Twenty-centimeter,we identify four late-type Galaxies with double Radio lobes(la GRls):J0217-3645,J0947+6220,J1412+3723 and J1736+*** previously known la GRls,we confirm the correlation between radio power P_(1.4GHz)and stellar mass M_(*)of host ***(25/35)la GRls belong to the blue cloud galaxies,while the newly identified cases in this work are located within the region of the red *** find a clear correlation between the differential radio power,i.e.,the offset from the P_(1.4GHz)-M_(*)relation,and the galaxy color,indicating that bluer galaxies at a fixed M_(*)tend to host more powerful radio ***,the majority(31/36)of la GRls are either located in a galaxy group or displaying a disturbed *** suggest that all of the galaxy mass,color and surrounding environment could play important roles in triggering radio lobes in late-type galaxies.

关键词： galaxies:active galaxies:jets galaxies:spiral radio continuum:galaxies

Structural basis for polyuridine tract recognition by SARS-CoV-2 Nsp15

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Protein & Cell 2024年第7期15卷 547-552页

作者： Fumiaki Ito Hanjing Yang z.Hong zhou Xiaojiang S.Chen Molecular and Computational Biology Department of Biological SciencesUniversity of Southern CaliforniaLos AngelesCA 90089United States Department of Microbiology Immunology and Molecular GeneticsUniversity of CaliforniaLos AngelesCA 90095United States California NanoSystems Institute University of CaliforniaLos AngelesCA90095United States Genetic Molecular and Cellular Biology ProgramKeck School of MedicineUniversity of Southern CaliforniaLos AngelesCA 90089United States Norris Comprehensive Cancer Center University of Southern CaliforniaLos AngelesCA 90089United States Center of Excellence in NanoBiophysics University of Southern CaliforniaLos AngelesCA 90089United States

Dear Editor,Coronaviruses have evolved a wide array of tactics to evade host antiviral *** host cells detect invading foreign nucleic acids including viral genome and viral replication intermediates,they activate interferon(IFN)signaling via cytoplasmic pattern recognition receptors(Kang et al.,2002;Kato et al.,2006).Remarkable stealth activities exhibited by coronaviruses are facilitated by a series of non-structural proteins(Nsps),such as Nsp15(Deng and Baker,2018;Deng et al.,2019;Hackbart et al.,2020),which is a uridine-specific endoribonuclease that mediates evasion of host detection of viral double-stranded RNA(dsRNA)(Bhardwaj et al.,2004;Deng et al.,2017;Frazier et al.,2021;Ivanov et al.,2004).Nsp15 targets a polyuridine[poly(U)]tract on the coronavirus negative strand RNA(Hackbart et al.,2020).Nsp15 limits the abundance and length of poly(U)within the negative strand RNA 5ʹ-extension by trimming down the initially synthesized poly(U)lead sequence to the optimal length that can suppress dsRNA formation but still serves as a template for poly(A)tail of the positive strand genome of the coronaviruses(Hofmann and Brian,1991).

关键词： p15 interferon template

Rational design of AgGaS/znS/znS quantum dots with a near-unity photoluminescence quantum yield via double shelling scheme

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Journal of Materials Science & Technology 2024年第2期169卷 235-242页

作者： H.X.lu H.liu z.z.Fu Y.Y.Chen H.Q.Dai z.Hu W.l.z.ang R.Q.Guo Institute for Electric light Sources School of Information Science and TechnologyFudan UniversityShanghai 200433China Institute of Future lighting Academy for Engineering and TechnologyFudan UniversityShanghai 200433China Yiwu Research Institute of Fudan University YiwuZhejiang 322000China zhongshan-Fudan Joint Innovation Center Zhongshan 528437China

In this study,a two-step method was used to synthesize highly luminescent AgGaS/znS/znS quantum dots(QDs).In the first step,an inner znS shell was formed via a one-pot method,which resulted in a smaller lattice mismatch between the AgGaS core and the outer znS shell,thereby facilitating the formation of a thick outer *** the two-step shelling process,the synthesized AgGaS/znS/znS QDs showed an excellent photoluminescence quantum yield(PlQY)of 96.4%with a peak wavelength of 508 nm,repre-senting the highest PlQY reported thus far for AgGaS ***,the effect of halogen ions in zn precursors on the shelling process was *** was proposed that the capacity of halogen ions to coordinate with the QDs influenced the balance between zn cation diffusion and znS shelling ***,the znS shelling reaction was dominant when znCl_(2)was employed,while zn cation diffusion was the dominant process under the I^(−)-rich *** work provides insights into the interfacial restructuring during the znS shelling and offers a clear map for the tailored synthesis of core/shell QDs.

关键词： AgGaS Quantum dots Photoluminescence Core/shell Alloyed core/shell interface

A multi-sensor appiproach to calving detection

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Information Processing in Agriculture 2024年第1期11卷 45-64页

作者： Anita z.Chang David l.Swain Mark G.Trotter Institute for Future Farming Systems School of HealthMedicaland Applied SciencesCentral Queensland UniversityRockhamptonQueensland 4700Australia

The advent of remote livestock monitoring systems provides numerous possibilities for improving on-farm productivity,efficiency,and *** potential application for these systems is for the detection of calving *** study describes the integration of data from multiple sensor sources,including accelerometers,global navigation satellite systems(GNsS),an accelerometer-derived rumination algorithm,a walk-over-weigh unit,and a weather station for parturition detection using a support vector machine *** best performing model utilised data from GNsS,the ruminating algorithm,and weather stations to achieve 98.6%accuracy,with 88.5%sensitivity and 100%*** topranking features of this model were primarily GNSS *** study provides an overview as to how various sensor systems could be integrated on-farm to maximise calving detection for improved production and welfare outcomes.

关键词： Accelerometer GNSS GPS Rumination Sensor WOW

Prediction of the undrained shear strength of remolded soil with non-linear regression,fuzzy logic,and artificial neural network

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Journal of Mountain Science 2024年第9期21卷 3108-3122页

作者： YÜNKÜl Kaan KARAÇOR Fatih GÜRBÜz Ayhan BUDAK TahsinÖmür Department of Civil Engineering Faculty of Engineering and ArchitectureTokat Gaziosmanpaşa UniversityTokat 60100Türkiye Department of Civil Engineering Faculty of Engineering and ArchitectureKafkas UniversityKars 36000Türkiye Department of Civil Engineering Faculty of EngineeringGazi UniversityAnkara 06570Türkiye Ministry of Youth and Sports Ankara 06090Türkiye

This study aims to predict the undrained shear strength of remolded soil samples using non-linear regression analyses,fuzzy logic,and artificial neural network modeling.A total of 1306 undrained shear strength results from 230 different remolded soil test settings reported in 21 publications were collected,util.z.ng six different measurement *** water content,plastic limit,and liquid limit were used as input parameters for fuzzy logic and artificial neural network modeling,liquidity index or water content ratio was considered as an input parameter for non-linear regression *** non-linear regression analyses,12 different regression equations were derived for the prediction of undrained shear strength of remolded ***-Forward backpropagation and the TANSIG transfer function were used for artificial neural network modeling,while the Mamdani inference system was preferred with trapezoidal and triangular membership functions for fuzzy logic *** experimental results of 914 tests were used for training of the artificial neural network models,196 for validation and 196 for *** was observed that the accuracy of the artificial neural network and fuzzy logic modeling was higher than that of the non-linear regression ***,a simple and reliable regression equation was proposed for assessments of undrained shear strength values with higher coefficients of determination.

关键词： Undrained shear strength liquidity index Water content ratio Non-linear regression Artificial neural networks Fuzzy logic

Water-soluble brown carbon in atmospheric aerosols from the resource-dependent cities:Optical properties,chemical compositions and sources

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Journal of Environmental Sciences 2024年第4期138卷 74-87页

作者： Haoji Wang Yue Su Yangzheng liu Fei Xie Xingjun zhou Ruihong Yu Changwei lü Jiang He School of Ecology and Environment Inner Mongolia UniversityHohhot 010021China Institute of Environmental Geology Inner Mongolia UniversityHohhot 010021China Environmental Monitoring Center of Inner Mongolia Hohhot 010011China

As a vital type of light-absorbing aerosol,brown carbon(BrC)presents inherent associations with atmospheric photochemistry and climate ***,the understanding of the chemical and optical properties of BrC is limited,especially in some resource-dependent cities with long heating periods in northwest *** study showed that the annual average abundances of Water-soluble BrC(WS-BrC)were 9.33±7.42 and 8.69±6.29μg/m^(3)in Baotou and Wuhai and the concentrations,absorption coefficient(Abs_(365)),and mass absorption efficiency(MAE365)of WS-BrC presented significant seasonal patterns,with high values in the heating season and low values in the non-heating season;while showing opposite seasonal trends for the Absorption Angstr?m exponent(AAE_(300-400)).Comparatively,the levels of WS-BrC in developing regions(such as cities in Asia)were higher than those in developed regions(such as cities in Europe and Australia),indicating the significant differences in energy consumption in these *** combining fluorescence excitation-emission matrix(EEM)spectra with the parallel factor(PARAFAC)model,humic-like(C1 and C2)and proteinlike(C3)substances were identified,and accounted for 61.40%±4.66%and 38.6%±3.78%at Baotou,and 60.33%±6.29%and 39.67%±4.17%at Wuhai,*** results of source apportionment suggested that the potential source regions of WS-BrC varied in heating ***-heating seasons and that the properties of WS-BrC significantly depended on primary emissions(e.g.,combustion emissions)and secondary formation.

关键词： Water-soluble brown carbon Atmospheric aerosols Optical properties PARAFAC Source apportionment

Photo-responsive functional materials based on light-driven molecular motors

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light(Science & Applications) 2024年第3期13卷 407-420页

作者： Yanping Deng Guiying long Yang zhang Wei zhao Guofu zhou Ben l.Feringa Jiawen Chen SCNU-UG International Joint laboratory of Molecular Science and Displays National Center for International Research on Green OptoelectronicsSouth China Normal UniversityGuangzhou 510006China Stratingh Institute for Chemistry University of GroningenNijenborgh 49747AG GroningenThe Netherlands

In the past two decades,the research and development of light-triggered molecular machines have mainly focused on developing molecular devices at the nanoscale.A key scientific issue in the field is how to amplify the controlled motion of molecules at the nanoscale along multiple length scales,such as the mesoscopic or the macroscopic scale,or in a more practical perspective,how to convert molecular motion into changes of properties of a macroscopic ***-driven molecular motors are able to perform repetitive unidirectional rotation upon irradiation,which offers unique opportunities for responsive macroscopic *** several reviews that focus on the design,synthesis and operation of the motors at the nanoscale,photo-responsive macroscopic materials based on light-driven molecular motors have not been comprehensively *** the present review,we first discuss the strategy of confining absolute molecular rotation into relative rotation by grafting motors on ***,examples of self-assemble motors in supramolecular polymers with high internal order are ***,we will focus on building of motors in a covalently linked system such as polymeric gels and polymeric liquid crystals to generate complex responsive ***,a perspective toward future developments and opportunities is *** review helps us getting a more and more clear picture and understanding on how complex movement can be programmed in light-responsive systems and how man-made adaptive materials can be invented,which can serve as an important guideline for further design of complex and advanced responsive materials.

关键词： functions materials material