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Viscosity and structure relationship with equimolar substitution of CaO with MgO in the CaO–MgO–Al_(2)O_(3)–SiO_(2)slag melts
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作者 Yong Hou Shuo Zhang +3 位作者 Jie Dang Jia Guo Hanghang Zhou Xuewei Lü 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期70-79,共10页
Currently,the Al_(2)O_(3)content in the high-alumina slag systems within blast furnaces is generally limited to 16wt%–18.5wt%,making it challenging to overcome this limitation.Unlike most studies that concentrated on... Currently,the Al_(2)O_(3)content in the high-alumina slag systems within blast furnaces is generally limited to 16wt%–18.5wt%,making it challenging to overcome this limitation.Unlike most studies that concentrated on managing the MgO/Al_(2)O_(3)ratio or basicity,this paper explored the effect of equimolar substitution of MgO for CaO on the viscosity and structure of a high-alumina CaO-MgO-Al_(2)O_(3)-SiO_(2)slag system,providing theoretical guidance and data to facilitate the application of high-alumina ores.The results revealed that the viscosity first decreased and then increased with higher MgO substitution,reaching a minimum at 15mol%MgO concentration.Fourier transform infrared spectroscopy(FTIR)results found that the depths of the troughs representing[SiO_(4)]tetrahedra,[AlO_(4)]tetrahedra,and Si-O-Al bending became progressively deeper with increased MgO substitution.Deconvolution of the Raman spectra showed that the average number of bridging oxygens per Si atom and the X_(Q^(3))/X_(Q^(2))(X_(Q^(i))is the molar fraction of Q^(i) unit,and i is the number of bridging oxygens in a[SiO_(4)]tetrahedral unit)ratio increased from 2.30 and 1.02 to 2.52 and 2.14,respectively,indicating a progressive polymerization of the silicate structure.X-ray photoelectron spectroscopy(XPS)results highlighted that non-bridging oxygen content decreased from 77.97mol% to 63.41mol% with increasing MgO concentration,whereas bridging oxygen and free oxygen contents increased.Structural analysis demonstrated a gradual increase in the polymerization degree of the tetrahedral structure with the increase in MgO substitution.However,bond strength is another important factor affecting the slag viscosity.The occurrence of a viscosity minimum can be attributed to the complex evolution of bond strengths of non-bridging oxygens generated during depolymerization of the[SiO_(4)]and[AlO_(4)]tetrahedral structures by CaO and MgO. 展开更多
关键词 ALUMINOSILICATE VISCOSITY structure spectroscopy
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A comparison study on structure-function relationship of polysaccharides obtained from sea buckthorn berries using different methods:antioxidant and bile acid-binding capacity 被引量:5
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作者 Qiaoyun Li Zuman Dou +5 位作者 Qingfei Duan Chun Chen Ruihai Liu Yueming Jiang Bao Yang Xiong Fu 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期494-505,共12页
In this study,the structural characters,antioxidant activities and bile acid-binding ability of sea buckthorn polysaccharides(HRPs)obtained by the commonly used hot water(HRP-W),pressurized hot water(HRP-H),ultrasonic... In this study,the structural characters,antioxidant activities and bile acid-binding ability of sea buckthorn polysaccharides(HRPs)obtained by the commonly used hot water(HRP-W),pressurized hot water(HRP-H),ultrasonic(HRP-U),acid(HRP-C)and alkali(HRP-A)assisted extraction methods were investigated.The results demonstrated that extraction methods had significant effects on extraction yield,monosaccharide composition,molecular weight,particle size,triple-helical structure,and surface morphology of HRPs except for the major linkage bands.Thermogravimetric analysis showed that HRP-U with filamentous reticular microstructure exhibited better thermal stability.The HRP-A with the lowest molecular weight and highest arabinose content possessed the best antioxidant activities.Moreover,the rheological analysis indicated that HRPs with higher galacturonic acid content and molecular weight showed higher viscosity and stronger crosslinking network(HRP-C,HRP-W and HRP-U),which exhibited stronger bile acid binding capacity.The present findings provide scientific evidence in the preparation technology of sea buckthorn polysaccharides with good antioxidant and bile acid binding capacity which are related to the structure affected by the extraction methods. 展开更多
关键词 Sea buckthorn Extraction method structure Rheological properties Antioxidant activity Bile acid binding capacity
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Advanced Functional Electromagnetic Shielding Materials:A Review Based on Micro‑Nano Structure Interface Control of Biomass Cell Walls
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作者 Yang Shi Mingjun Wu +14 位作者 Shengbo Ge Jianzhang Li Anoud Saud Alshammari Jing Luo Mohammed A.Amin Hua Qiu Jinxuan Jiang Yazeed M.Asiri Runzhou Huang Hua Hou Zeinhom M.El‑Bahy Zhanhu Guo Chong Jia Kaimeng Xu Xiangmeng Chen 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期98-134,共37页
Research efforts on electromagnetic interference(EMI)shielding materials have begun to converge on green and sustainable biomass materials.These materials offer numerous advantages such as being lightweight,porous,and... Research efforts on electromagnetic interference(EMI)shielding materials have begun to converge on green and sustainable biomass materials.These materials offer numerous advantages such as being lightweight,porous,and hierarchical.Due to their porous nature,interfacial compatibility,and electrical conductivity,biomass materials hold significant potential as EMI shielding materials.Despite concerted efforts on the EMI shielding of biomass materials have been reported,this research area is still relatively new compared to traditional EMI shielding materials.In particular,a more comprehensive study and summary of the factors influencing biomass EMI shielding materials including the pore structure adjustment,preparation process,and micro-control would be valuable.The preparation methods and characteristics of wood,bamboo,cellulose and lignin in EMI shielding field are critically discussed in this paper,and similar biomass EMI materials are summarized and analyzed.The composite methods and fillers of various biomass materials were reviewed.this paper also highlights the mechanism of EMI shielding as well as existing prospects and challenges for development trends in this field. 展开更多
关键词 Biomass materials Electromagnetic interference shielding Micro-nano structure interface control CONDUCTIVITY
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Mechanical responses of anchoring structure under triaxial cyclic loading 被引量:2
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作者 Peng Wang Nong Zhang +5 位作者 Qun Wei Xingliang Xu Guangzhen Cui Aoran Li Sen Yang Jiaguang Kan 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期545-560,共16页
Dynamic load on anchoring structures(AS)within deep roadways can result in cumulative damage and failure.This study develops an experimental device designed to test AS under triaxial loads.The device enables the inves... Dynamic load on anchoring structures(AS)within deep roadways can result in cumulative damage and failure.This study develops an experimental device designed to test AS under triaxial loads.The device enables the investigation of the mechanical response,failure mode,instability assessment criteria,and anchorage effect of AS subjected to combined cyclic dynamic-static triaxial stress paths.The results show that the peak bearing strength is positively correlated with the anchoring matrix strength,anchorage length,and edgewise compressive strength.The bearing capacity decreases significantly when the anchorage direction is severely inclined.The free face failure modes are typically transverse cracking,concave fracturing,V-shaped slipping and detachment,and spallation detachment.Besides,when the anchoring matrix strength and the anchorage length decrease while the edgewise compressive strength,loading rate,and anchorage inclination angle increase,the failure intensity rises.Instability is determined by a negative tangent modulus of the displacement-strength curve or the continued deformation increase against the general downward trend.Under cyclic loads,the driving force that breaks the rock mass along the normal vector and the rigidity of the AS are the two factors that determine roadway stability.Finally,a control measure for surrounding rock stability is proposed to reduce the internal driving force via a pressure relief method and improve the rigidity of the AS by full-length anchorage and grouting modification. 展开更多
关键词 Triaxial stress Dynamic-static combination load Cyclic loading Anchoring structure(AS) Cumulative damage
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Emerging structures and dynamic mechanisms ofγ-secretase for Alzheimer’s disease
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作者 Yinglong Miao Michael S.Wolfe 《Neural Regeneration Research》 SCIE CAS 2025年第1期174-180,共7页
γ-Secretase,called“the proteasome of the membrane,”is a membrane-embedded protease complex that cleaves 150+peptide substrates with central roles in biology and medicine,including amyloid precursor protein and the ... γ-Secretase,called“the proteasome of the membrane,”is a membrane-embedded protease complex that cleaves 150+peptide substrates with central roles in biology and medicine,including amyloid precursor protein and the Notch family of cell-surface receptors.Mutations inγ-secretase and amyloid precursor protein lead to early-onset familial Alzheimer’s disease.γ-Secretase has thus served as a critical drug target for treating familial Alzheimer’s disease and the more common late-onset Alzheimer’s disease as well.However,critical gaps remain in understanding the mechanisms of processive proteolysis of substrates,the effects of familial Alzheimer’s disease mutations,and allosteric modulation of substrate cleavage byγ-secretase.In this review,we focus on recent studies of structural dynamic mechanisms ofγ-secretase.Different mechanisms,including the“Fit-Stay-Trim,”“Sliding-Unwinding,”and“Tilting-Unwinding,”have been proposed for substrate proteolysis of amyloid precursor protein byγ-secretase based on all-atom molecular dynamics simulations.While an incorrect registry of the Notch1 substrate was identified in the cryo-electron microscopy structure of Notch1-boundγ-secretase,molecular dynamics simulations on a resolved model of Notch1-boundγ-secretase that was reconstructed using the amyloid precursor protein-boundγ-secretase as a template successfully capturedγ-secretase activation for proper cleavages of both wildtype and mutant Notch,being consistent with biochemical experimental findings.The approach could be potentially applied to decipher the processing mechanisms of various substrates byγ-secretase.In addition,controversy over the effects of familial Alzheimer’s disease mutations,particularly the issue of whether they stabilize or destabilizeγ-secretase-substrate complexes,is discussed.Finally,an outlook is provided for future studies ofγ-secretase,including pathways of substrate binding and product release,effects of modulators on familial Alzheimer’s disease mutations of theγ-secretase-substrate complexes.Comprehensive understanding of the functional mechanisms ofγ-secretase will greatly facilitate the rational design of effective drug molecules for treating familial Alzheimer’s disease and perhaps Alzheimer’s disease in general. 展开更多
关键词 Alzheimer’s disease amyloid precursor protein cryo-EM structures drug design intramembrane proteolysis molecular dynamics NOTCH
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Tuning electronic structure of RuO_(2)by single atom Zn and oxygen vacancies to boost oxygen evolution reaction in acidic medium 被引量:1
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作者 Qing Qin Tiantian Wang +7 位作者 Zijian Li Guolin Zhang Haeseong Jang Liqiang Hou Yu Wang Min Gyu Kim Shangguo Liu Xien Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期94-102,I0003,共10页
The poor stability of RuO_(2)electrocatalysts has been the primary obstacles for their practical application in polymer electrolyte membrane electrolyzers.To dramatically enhance the durability of RuO_(2)to construct ... The poor stability of RuO_(2)electrocatalysts has been the primary obstacles for their practical application in polymer electrolyte membrane electrolyzers.To dramatically enhance the durability of RuO_(2)to construct activity-stability trade-off model is full of significance but challenging.Herein,a single atom Zn stabilized RuO_(2)with enriched oxygen vacancies(SA Zn-RuO_(2))is developed as a promising alternative to iridium oxide for acidic oxygen evolution reaction(OER).Compared with commercial RuO_(2),the enhanced Ru–O bond strength of SA Zn-RuO_(2)by forming Zn-O-Ru local structure motif is favorable to stabilize surface Ru,while the electrons transferred from Zn single atoms to adjacent Ru atoms protects the Ru active sites from overoxidation.Simultaneously,the optimized surrounding electronic structure of Ru sites in SA ZnRuO_(2)decreases the adsorption energies of OER intermediates to reduce the reaction barrier.As a result,the representative SA Zn-RuO_(2)exhibits a low overpotential of 210 mV to achieve 10 mA cm^(-2)and a greatly enhanced durability than commercial RuO_(2).This work provides a promising dual-engineering strategy by coupling single atom doping and vacancy for the tradeoff of high activity and catalytic stability toward acidic OER. 展开更多
关键词 ELECTROCATALYST Acidic oxygen evolution reaction Electronic structure engineering DURABILITY Reaction barrier
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Designing Electronic Structures of Multiscale Helical Converters for Tailored Ultrabroad Electromagnetic Absorption
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作者 Zhaobo Feng Chongbo Liu +7 位作者 Xin Li Guangsheng Luo Naixin Zhai Ruizhe Hu Jing Lin Jinbin Peng Yuhui Peng Renchao Che 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期439-455,共17页
Atomic-scale doping strategies and structure design play pivotal roles in tailoring the electronic structure and physicochemical property of electromagnetic wave absorption(EMWA)materials.However,the relationship betw... Atomic-scale doping strategies and structure design play pivotal roles in tailoring the electronic structure and physicochemical property of electromagnetic wave absorption(EMWA)materials.However,the relationship between configuration and electromagnetic(EM)loss mechanism has remained elusive.Herein,drawing inspiration from the DNA transcription process,we report the successful synthesis of novel in situ Mn/N co-doped helical carbon nanotubes with ultrabroad EMWA capability.Theoretical calculation and EM simulation confirm that the orbital coupling and spin polarization of the Mn–N4–C configuration,along with cross polarization generated by the helical structure,endow the helical converters with enhanced EM loss.As a result,HMC-8 demonstrates outstanding EMWA performance,achieving a minimum reflection loss of−63.13 dB at an ultralow thickness of 1.29 mm.Through precise tuning of the graphite domain size,HMC-7 achieves an effective absorption bandwidth(EAB)of 6.08 GHz at 2.02 mm thickness.Furthermore,constructing macroscale gradient metamaterials enables an ultrabroadband EAB of 12.16 GHz at a thickness of only 5.00 mm,with the maximum radar cross section reduction value reaching 36.4 dB m2.This innovative approach not only advances the understanding of metal–nonmetal co-doping but also realizes broadband EMWA,thus contributing to the development of EMWA mechanisms and applications. 展开更多
关键词 Metal-nonmetal co-doping 3d-2p orbital coupling Spin polarization Helical structure Broadband EM wave absorption
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Structural Modal Parameter Recognition and Related Damage Identification Methods under Environmental Excitations: A Review
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作者 Chao Zhang Shang-Xi Lai Hua-Ping Wang 《Structural Durability & Health Monitoring》 EI 2025年第1期25-54,共30页
Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the structure.Therefore,it is particularly significant to identify the structural modal parameters accordi... Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the structure.Therefore,it is particularly significant to identify the structural modal parameters according to the monitoring data information in the structural health monitoring(SHM)system,so as to provide a scientific basis for structural damage identification and dynamic model modification.In view of this,this paper reviews methods for identifying structural modal parameters under environmental excitation and briefly describes how to identify structural damages based on the derived modal parameters.The paper primarily introduces data-driven modal parameter recognition methods(e.g.,time-domain,frequency-domain,and time-frequency-domain methods,etc.),briefly describes damage identification methods based on the variations of modal parameters(e.g.,natural frequency,modal shapes,and curvature modal shapes,etc.)and modal validation methods(e.g.,Stability Diagram and Modal Assurance Criterion,etc.).The current status of the application of artificial intelligence(AI)methods in the direction of modal parameter recognition and damage identification is further discussed.Based on the pre-vious analysis,the main development trends of structural modal parameter recognition and damage identification methods are given to provide scientific references for the optimized design and functional upgrading of SHM systems. 展开更多
关键词 structural health monitoring data information modal parameters damage identification AI method
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Resistive switching behavior and mechanism of HfO_(x) films with large on/off ratio by structure design
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作者 黄香林 王英 +2 位作者 黄慧香 段理 郭婷婷 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期660-665,共6页
Different bilayer structures of HfO_(x)/Ti(TiO_(x)) are designed for hafnium-based memory to investigate the switching characteristics. The chemical states in the films and near the interface are characterized by x-ra... Different bilayer structures of HfO_(x)/Ti(TiO_(x)) are designed for hafnium-based memory to investigate the switching characteristics. The chemical states in the films and near the interface are characterized by x-ray photoelectron spectroscopy,and the oxygen vacancies are analyzed. Highly improved on/off ratio(~104) and much uniform switching parameters are observed for bilayer structures compared to single layer HfO_(x) sample, which can be attributed to the modulation of oxygen vacancies at the interface and better control of the growth of filaments. Furthermore, the reliability of the prepared samples is investigated. The carrier conduction behaviors of HfO_(x)-based samples can be attributed to the trapping and de-trapping process of oxygen vacancies and a filamentary model is proposed. In addition, the rupture of filaments during the reset process for the bilayer structures occur at the weak points near the interface by the recovery of oxygen vacancies accompanied by the variation of barrier height. The re-formation of fixed filaments due to the residual filaments as lightning rods results in the better switching performance of the bilayer structure. 展开更多
关键词 HfO_(x)film resistive switching structure design interface modulation
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Structure and superconducting properties of Ru_(1-x)Mo_(x)(x=0.1-0.9)alloys
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作者 付阳 龚春生 +3 位作者 涂志俊 田尚杰 王守国 雷和畅 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期173-179,共7页
We report the detailed crystal structures and physical properties of Ru_(1-x)Mo_(x)alloys in the solid solution range of x=0.1-0.9.Structure characterizations indicate that the crystal structure changes from the hcp-M... We report the detailed crystal structures and physical properties of Ru_(1-x)Mo_(x)alloys in the solid solution range of x=0.1-0.9.Structure characterizations indicate that the crystal structure changes from the hcp-Mg-type,toβ-CrFe-type,and then bcc-W-type.The measurements of physical properties show that the Ru_(1-x)Mo_(x)samples with x≥0.2are superconductors and the superconducting transition temperature T_c as a function of Mo content exhibits a dome-like behavior. 展开更多
关键词 SUPERCONDUCTIVITY alloy crystal structures Ru_(1-x)Mo_(x)
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Enhancing electromagnetic wave absorption with core‐shell structured SiO_(2)@MXene@MoS_(2) nanospheres 被引量:1
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作者 Xuewen Jiang Qian Wang +7 位作者 Limeng Song Hongxia Lu Hongliang Xu Gang Shao Hailong Wang Rui Zhang Changan Wang Bingbing Fan 《Carbon Energy》 SCIE EI CAS CSCD 2024年第8期90-104,共15页
Material composition and structural design are important factors influencing the electromagnetic wave(EMW)absorption performance of materials.To alleviate the impedance mismatch attributed to the high dielectric const... Material composition and structural design are important factors influencing the electromagnetic wave(EMW)absorption performance of materials.To alleviate the impedance mismatch attributed to the high dielectric constant of Ti_(3)C_(2)T_(x)MXene,we have successfully synthesized core‐shell structured SiO_(2)@MXene@MoS_(2)nanospheres.This architecture,comprising SiO_(2) as the core,MXene as the intermediate layer,and MoS_(2) as the outer shell,is achieved through an electrostatic self‐assembly method combined with a hydrothermal process.This complex core‐shell structure not only provides a variety of loss mechanisms that effectively dissipate electromagnetic energy but also prevents self‐aggregation of MXene and MoS_(2) nanosheets.Notably,the synergistic combination of SiO_(2) and MoS_(2) with highly conductive MXene enables the suitable dielectric constant of the composites,ensuring optimal impedance matching.Therefore,the core‐shell structured SiO_(2)@MXene@MoS_(2) nanospheres exhibit excellent EMW absorption performance,featuring a remarkable minimum reflection loss(RL_(min))of−52.11 dB(2.4 mm).It is noteworthy that these nanospheres achieve an ultra‐wide effective absorption bandwidth(EAB)of 6.72 GHz.This work provides a novel approach for designing and synthesizing high‐performance EMW absorbers characterized by“wide bandwidth and strong reflection loss.” 展开更多
关键词 core‐shell structure electromagnetic wave absorption multiloss mechanism SiO_(2)@Mxene@MoS_(2)
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Temperature and structure measurements of heavy-ion-heated diamond using in situ X-ray diagnostics
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作者 J.Lutgert P.Hesselbach +20 位作者 M.Schorner V.Bagnoud R.Belikov P.Drechsel B.Heuser O.SHumphries P.Katrik B.Lindqvist C.Qu R.Redmer D.Riley G.Schaumann S.Schumacher A.Tauschwitz D.Varentsov K.Weyrich X.Yu B.Zielbauer Zs.Major P.Neumayer D.Kraus 《Matter and Radiation at Extremes》 SCIE EI CSCD 2024年第4期80-89,共10页
We present in situ measurements of spectrally resolved X-ray scattering and X-ray diffraction from monocrystalline diamond samples heatedwith an intense pulse of heavy ions.In this way,we determine the samples’heatin... We present in situ measurements of spectrally resolved X-ray scattering and X-ray diffraction from monocrystalline diamond samples heatedwith an intense pulse of heavy ions.In this way,we determine the samples’heating dynamics and their microscopic and macroscopic structuralintegrity over a timespan of several microseconds.Connecting the ratio of elastic to inelastic scattering with state-of-the-art density functionaltheory molecular dynamics simulations allows the inference of average temperatures around 1300 K,in agreement with predictions fromstopping power calculations.The simultaneous diffraction measurements show no hints of any volumetric graphitization of the material,butdo indicate the onset of fracture in the diamond sample.Our experiments pave the way for future studies at the Facility for Antiproton andIon Research,where a substantially increased intensity of the heavy ion beam will be available. 展开更多
关键词 HEATED INTENSE structure
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The Clumpy Structure of Five Star-bursting Dwarf Galaxies in the MaNGA Survey
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作者 Mengting Ju Jun Yin +6 位作者 Lei Hao Chenxu Liu Chao-Wei Tsai Junfeng Wang Zhengyi Shao Shuai Feng Yu Rong 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第2期83-103,共21页
The star-forming clumps in star-bursting dwarf galaxies provide valuable insights into understanding the evolution of dwarf galaxies.In this paper,we focus on five star-bursting dwarf galaxies featuring off-centered c... The star-forming clumps in star-bursting dwarf galaxies provide valuable insights into understanding the evolution of dwarf galaxies.In this paper,we focus on five star-bursting dwarf galaxies featuring off-centered clumps in the Mapping Nearby Galaxies at Apache Point Observatory survey.Using the stellar population synthesis software Fitting Analysis using Differential evolution Optimization,we obtain the spatially resolved distribution of the star formation history,which allows us to construct the g-band images of the five galaxies at different ages.These images can help us to probe the evolution of the morphological structures of these galaxies.While images of a stellar population older than 1 Gyr are typically smooth,images of a stellar population younger than 1 Gyr reveal significant clumps,including multiple clumps which appear at different locations and even different ages.To study the evolutionary connections of these five galaxies to other dwarf galaxies before their star-forming clumps appear,we construct the images of the stellar populations older than three age nodes,and define them to be the images of the"host"galaxies.We find that the properties such as the central surface brightness and the effective radii of the hosts of the five galaxies are in between those of dwarf ellipticals(dEs)and dwarf irregulars(dIrrs),with two clearly more similar to dEs and one more similar to dIrrs.Among the five galaxies,8257-3704 is particularly interesting,as it shows a previous starburst event that is not quite visible from its gri image,but only visible from images of the stellar population at a few hundred million years.The star-forming clump associated with this event may have appeared at around 600 Myr ago and disappeared at around 40 Myr ago. 展开更多
关键词 GALAxIES dwarf-galaxies evolution-galaxies formation-Galaxy structure
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Deformation,structure and potential hazard of a landslide based on InSAR in Banbar county,Xizang(Tibet) 被引量:1
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作者 Guan-hua Zhao Heng-xing Lan +4 位作者 Hui-yong Yin Lang-ping Li Alexander Strom Wei-feng Sun Chao-yang Tian 《China Geology》 CAS CSCD 2024年第2期203-221,共19页
The Tibetan Plateau is characterized by complex geological conditions and a relatively fragile ecological environment.In recent years,there has been continuous development and increased human activity in the Tibetan P... The Tibetan Plateau is characterized by complex geological conditions and a relatively fragile ecological environment.In recent years,there has been continuous development and increased human activity in the Tibetan Plateau region,leading to a rising risk of landslides.The landslide in Banbar County,Xizang(Tibet),have been perturbed by ongoing disturbances from human engineering activities,making it susceptible to instability and displaying distinct features.In this study,small baseline subset synthetic aperture radar interferometry(SBAS-InSAR)technology is used to obtain the Line of Sight(LOS)deformation velocity field in the study area,and then the slope-orientation deformation field of the landslide is obtained according to the spatial geometric relationship between the satellite’s LOS direction and the landslide.Subsequently,the landslide thickness is inverted by applying the mass conservation criterion.The results show that the movement area of the landslide is about 6.57×10^(4)m^(2),and the landslide volume is about 1.45×10^(6)m^(3).The maximum estimated thickness and average thickness of the landslide are 39 m and 22 m,respectively.The thickness estimation results align with the findings from on-site investigation,indicating the applicability of this method to large-scale earth slides.The deformation rate of the landslide exhibits a notable correlation with temperature variations,with rainfall playing a supportive role in the deformation process and displaying a certain lag.Human activities exert the most substantial influence on the spatial heterogeneity of landslide deformation,leading to the direct impact of several prominent deformation areas due to human interventions.Simultaneously,utilizing the long short-term memory(LSTM)model to predict landslide displacement,and the forecast results demonstrate the effectiveness of the LSTM model in predicting landslides that are in a continuous development and movement phase.The landslide is still active,and based on the spatial heterogeneity of landslide deformation,new recommendations have been proposed for the future management of the landslide in order to mitigate potential hazards associated with landslide instability. 展开更多
关键词 LANDSLIDE INSAR Human activity DEFORMATION structure LSTM model Engineering construction Thickness Neural network Machine learning Prediction and prevention Tibetan Plateau Geological hazards survey engineering
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Mechanical responses of underground carriageway structures due to construction of metro tunnels beneath the existing structure:A case study
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作者 Xin Han Fei Ye +3 位作者 Xingbo Han Chao Ren Jing Song Ruliang Zhao 《Deep Underground Science and Engineering》 2024年第2期231-246,共16页
To understand the mechanical response pattern of the existing structure and ground due to the construction of metro tunnels underneath,the finite difference method is adopted to study the torsional deformation and str... To understand the mechanical response pattern of the existing structure and ground due to the construction of metro tunnels underneath,the finite difference method is adopted to study the torsional deformation and stress variation of the existing structure and the effect of underground carriageway structures on the surface subsidence.The curves of the maximum differential subsidence,torsion angle,and distortion of the cross-section of the existing structure show two peaks in succession during traversing of two metro tunnels beneath it.The torsion angle of the existing structure changes when the two tunnels traverse beneath it in opposite directions.The first traversing of the shield tunnel mainly induces the magnitude variation in torsional deformation of the existing structure,but the second traversing of the subsurface tunnel may cause a dynamic change in the magnitude and form of torsional deformation in the existing structure.The shielding effect can reduce the surface subsidence caused by metro tunnel excavation to a certain extent,and the development trend of subsidence becomes slower as the excavation continues. 展开更多
关键词 metro tunnel numerical simulation structural deformation surface subsidence underground carriageway structure
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Ingenious liquid-observed vapor exchange (LOVE) NMR method revealing how sugars protect dry protein structure
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作者 Geying Ru Conggang Li 《Magnetic Resonance Letters》 2024年第2期75-76,共2页
Recently,Gary et al.published an article elucidating how sugars contribute to the protection of dry protein structure.They utilized an ingenious liquid-observed vapor exchange(LOVE)nuclear magnetic resonance(NMR)metho... Recently,Gary et al.published an article elucidating how sugars contribute to the protection of dry protein structure.They utilized an ingenious liquid-observed vapor exchange(LOVE)nuclear magnetic resonance(NMR)method,providing valuable insights into the protection mechanism of sugars during the drying process.The details of their study can be found in the article available at https://doi.org/10.1021/acs.biochem.2c00692. 展开更多
关键词 structure SUGAR REVEALING
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Structural identification and antioxidative activity evaluation of flaxseed lignan macromolecules: structure-activity correlation
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作者 Chen Cheng Lei Wang +7 位作者 Xiao Yu Fenghong Huang Jing Yang Fang Geng Xiaoyang Xia Xia Xiang Shufang Xu Qianchun Deng 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第6期3224-3235,共12页
Flaxseed lignan macromolecules(FLM)are a class of important secondary metabolites in fl axseed,which have been widely concerned due to their biological and pharmacological properties,especially for their antioxidative... Flaxseed lignan macromolecules(FLM)are a class of important secondary metabolites in fl axseed,which have been widely concerned due to their biological and pharmacological properties,especially for their antioxidative activity.For the composition and structure of FLM,our results confirmed that ferulic acid glycoside(FerAG)was directly ester-linked with herbacetin diglucoside(HDG)or pinoresinol diglucoside(PDG),which might determine the beginning of FLM biosynthesis.Additionally,p-coumaric acid glycoside(CouAG)might determine the end of chain extension during FLM synthesis in fl axseed.FLM exhibited higher antioxidative activity in polar systems,as shown by its superior 1,1-diphenyl-2-picrylhydrazyl(DPPH)free radical scavenging capacity compared to the 2,2’-azinobis(3-ehtylbenzothiazolin-6-sulfnic acid)(ABTS)cation free radical scavenging capacity in non-polar systems.Moreover,the antioxidative activity of FLM was found to be highly dependent on its composition and structure.In particular,it was positively correlated with the number of phenolic hydroxyl groups(longer FLM chains)and inversely related to the steric hindrance at the ends(lower levels of FerAG and CouAG).These fi ndings verifi ed the potential application of FLM in nonpolar systems,particularly in functional food emulsions。 展开更多
关键词 Flaxseed lignan macromolecules Composition structure Antioxidative activity structure-ACTIVITY Correlation Flaxseed lignan macromolecules Composition structure Antioxidative activity structure-ACTIVITY CORRELATION
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Influence of Al_(2)O_(3)/SiO_(2) Ratio on the Structure and Properties of Na^(+)/K^(+)Ion Exchange Na_(2)O-MgO-Al_(2)O_(3)-SiO_(2) Glasses
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作者 吴建磊 CHEN Junzhu +4 位作者 TIAN Xiaokun LI Jiahao GAO Wenkai YUE Yunlong 康俊峰 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第3期606-612,共7页
In this work,the structure,viscosity and ion-exchange process of Na_(2)O-MgO-Al_(2)O_(3)-SiO_(2) glasses with different Al_(2)O_(3)/SiO_(2) molar ratios were investigated.The results showed that,with increasing Al_(2)... In this work,the structure,viscosity and ion-exchange process of Na_(2)O-MgO-Al_(2)O_(3)-SiO_(2) glasses with different Al_(2)O_(3)/SiO_(2) molar ratios were investigated.The results showed that,with increasing Al_(2)O_(3)/SiO_(2) ratio,the simple structural units Q_(1) and Q_(2) transformed into highly aggregated structural units Q_(3) and Q_(4),indicating the increase of polymerization degree of glass network.Meanwhile,the coefficient of thermal expansion decreased from 9.23×10^(-6)℃^(-1) to 8.88×10^(-6)℃^(-1).The characteristic temperatures such as melting,forming,softening and glass transition temperatures increased with the increase of Al_(2)O_(3)/SiO_(2) ratio,while the glasses working temperature range became narrow.The increasing Al_(2)O_(3)/SiO_(2) ratio and prolonging ion-exchange time enhanced the surface compressive stress(CS)and depth of stress layer(DOL).However,the increase of ion exchange temperature increased the DOL and decreased the CS affected by stress relaxation.There was a good linear relationship between stress relaxation and surface compressive stress.Chemical strengthening significantly improved the hardness of glasses,which reached the maximum value of(622.1±10)MPa for sample with Al_(2)O_(3)/SiO_(2) ratio of 0.27 after heat treated at 410℃for 2 h. 展开更多
关键词 network structure viscosity ion exchange aluminosilicate glass
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Experimental research on the launching system of auxiliary charge with filter cartridge structure
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作者 Zi-Jun Chen Ze He +2 位作者 Hong-Hao Ma Lu-Qing Wang Zhao-Wu Shen 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期41-48,共8页
A launching system with a filter cartridge structure was proposed to improve the muzzle velocity of the projectile.The combustion chamber of the launching system is divided into two fixed chambers,one is located in th... A launching system with a filter cartridge structure was proposed to improve the muzzle velocity of the projectile.The combustion chamber of the launching system is divided into two fixed chambers,one is located in the breech chamber,and the other is arranged in the barrel.The breech chamber charge was ignited first,and the charges in the auxiliary chambers were ignited by the high-temperature,highpressure combustible gas trailing the projectile.In this way,the combustible gas in the auxiliary chambers could compensate for the pressure drop caused by the movement of the projectile.The proposed device features the advantage of launching a projectile with high muzzle velocity without exceeding the maximum pressure in the chamber.In order to obtain some internal ballistic characteristics of the launch system,some critical structure,such as the length of the filter cartridge auxiliary charge,the combustion degree of the propellant in the chamber,and the length of the barrel,are discussed.The experimental results show that with the increased auxiliary charge length,a pressure plateau or even a secondary peak pressure can be formed,which is less than the peak pressure.The projectile velocity increased by 23.57%,14.64%,and 7.65%when the diaphragm thickness was 0 mm,1 mm,and2 mm,respectively.The muzzle velocity of the projectile can be increased by 13.42%by increasing the length of the barrel.Under the same charge condition,with the increase of barrel length,the energy utilization rate of propellant increases by 28.64%. 展开更多
关键词 Interior ballistics Charge structures Launch system Charge design
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Spatiotemporal dynamics of the social structure of Indo-Pacific humpback dolphins(Sousa chinensis)in Xiamen waters from 2007 to 2019
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作者 Yi Lu Xin-Rong Xu +3 位作者 Bing-Yao Chen Thomas A Jefferson Holly Fearnbach Guang Yang 《Zoological Research》 SCIE CSCD 2024年第2期439-450,共12页
As highly social animals,Indo-Pacific humpback dolphins(Sousa chinensis)exhibit community differentiation.Nevertheless,our understanding of the external and internal factors influencing these dynamics,as well as their... As highly social animals,Indo-Pacific humpback dolphins(Sousa chinensis)exhibit community differentiation.Nevertheless,our understanding of the external and internal factors influencing these dynamics,as well as their spatiotemporal variations,is still limited.In the present study,variations in the social structure of an endangered Indo-Pacific humpback dolphin population in Xiamen Bay,China,were monitored over two distinct periods(2007–2010 and 2017–2019)to analyze the effects of habitat utilization and the composition of individuals within the population.In both periods,the population demonstrated a strikingly similar pattern of social differentiation,characterized by the division of individuals into two main clusters and one small cluster.Spatially,the two primary clusters occupied the eastern and western waters,respectively,although the core distribution area of the eastern cluster shifted further eastward between the two periods.Despite this distribution shift,the temporal stability of the social structure and inter-associations within the eastern cluster remained unaffected.A subset of 16individuals observed in both periods,comprising 51.6%and 43.2%of the population in each respective period,emerged as a foundational element of the social structure and may be responsible for sustaining social structure stability,especially during the 2007–2010 period.These observations suggest that the composition of dominant individuals,an internal factor,had a more substantial influence on the formation of the social network than changes in habitat use,an external factor.Consequently,the study proposes distinct conservation measures tailored to each of the two main clusters. 展开更多
关键词 Social differentiation Social structure Sousa chinensis DYNAMICS CONSERVATION
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