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Structural Engineering of Hierarchical Magnetic/Carbon Nanocomposites via In Situ Growth for High-Efficient Electromagnetic Wave Absorption 被引量:1
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作者 Xianyuan Liu Jinman Zhou +1 位作者 Ying Xue Xianyong Lu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期262-278,共17页
Materials exhibiting high-performance electromagnetic wave absorption have garnered considerable scientific and technological attention,yet encounter significant challenges.Developing new materials and innovative stru... Materials exhibiting high-performance electromagnetic wave absorption have garnered considerable scientific and technological attention,yet encounter significant challenges.Developing new materials and innovative structural design concepts is crucial for expanding the application field of electromagnetic wave absorption.Particularly,hierarchical structure engineering has emerged as a promising approach to enhance the physical and chemical properties of materials,providing immense potential for creating versatile electromagnetic wave absorption materials.Herein,an exceptional multi-dimensional hierarchical structure was meticulously devised,unleashing the full microwave attenuation capabilities through in situ growth,selfreduction,and multi-heterogeneous interface integration.The hierarchical structure features a three-dimensional carbon framework,where magnetic nanoparticles grow in situ on the carbon skeleton,creating a necklace-like structure.Furthermore,magnetic nanosheets assemble within this framework.Enhanced impedance matching was achieved by precisely adjusting component proportions,and intelligent integration of diverse interfaces bolstered dielectric polarization.The obtain Fe_(3)O_(4)-Fe nanoparticles/carbon nanofibers/Al-Fe_(3)O_(4)-Fe nanosheets composites demonstrated outstanding performance with a minimum reflection loss(RLmin)value of−59.3 dB and an effective absorption bandwidth(RL≤−10 dB)extending up to 5.6 GHz at 2.2 mm.These notable accomplishments offer fresh insights into the precision design of high-efficient electromagnetic wave absorption materials. 展开更多
关键词 Electromagnetic wave absorption Hierarchical structure In situ growth Self-reduction
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Injectable and in situ foaming shape-adaptive porous Bio-based polyurethane scaffold used for cartilage regeneration 被引量:1
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作者 Abudureheman Bahatibieke Shuai Wei +9 位作者 Han Feng Jianming Zhao Mengjiao Ma Junfei Li Yajie Xie Kun Qiao Yanseng Wang Jiang Peng Haoye Meng Yudong Zheng 《Bioactive Materials》 SCIE CSCD 2024年第9期1-13,共13页
Irregular articular cartilage injury is a common type of joint trauma,often resulting from intense impacts and other factors that lead to irregularly shaped wounds,the limited regenerative capacity of cartilage and th... Irregular articular cartilage injury is a common type of joint trauma,often resulting from intense impacts and other factors that lead to irregularly shaped wounds,the limited regenerative capacity of cartilage and the mismatched shape of the scaffods have contributed to unsatisfactory therapeutic outcomes.While injectable materials are a traditional solution to adapt to irregular cartilage defects,they have limitations,and injectable materials often lack the porous microstructures favorable for the rapid proliferation of cartilage cells.In this study,an injectable porous polyurethane scaffold named PU-BDO-Gelatin-Foam(PUBGF)was prepared.After injection into cartilage defects,PUBGF forms in situ at the site of the defect and exhibits a dynamic microstructure during the initial two weeks.This dynamic microstructure endows the scaffold with the ability to retain substances within its interior,thereby enhancing its capacity to promote chondrogenesis.Furthermore,the chondral repair efficacy of PUBGF was validated by directly injecting it into rat articular cartilage injury sites.The injectable PUBGF scaffold demonstrates a superior potential for promoting the repair of cartilage defects when compared to traditional porous polyurethane scaffolds.The substance retention ability of this injectable porous scaffold makes it a promising option for clinical applications. 展开更多
关键词 INJECTABLE In situ forming POLYURETHANE Cartilage repair Tissue engineering
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Optimizing 3d spin polarization of CoOOH by in situ Mo doping for efficient oxygen evolution reaction 被引量:1
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作者 Zhichao Jia Yang Yuan +6 位作者 Yanxing Zhang Xiang Lyu Chenhong Liu Xiaoli Yang Zhengyu Bai Haijiang Wang Lin Yang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第1期236-244,共9页
Transition-metal oxyhydroxides are attractive catalysts for oxygen evolution reactions(OERs).Further studies for developing transition-metal oxyhydroxide catalysts and understanding their catalytic mechanisms will ben... Transition-metal oxyhydroxides are attractive catalysts for oxygen evolution reactions(OERs).Further studies for developing transition-metal oxyhydroxide catalysts and understanding their catalytic mechanisms will benefit their quick transition to the next catalysts.Herein,Mo-doped CoOOH was designed as a high-performance model electrocatalyst with durability for 20 h at 10 mAcm−2.Additionally,it had an overpotential of 260 mV(glassy carbon)or 215 mV(nickel foam),which was 78 mV lower than that of IrO_(2)(338 mV).In situ,Raman spectroscopy revealed the transformation process of CoOOH.Calculations using the density functional theory showed that during OER,doped Mo increased the spin-up density of states and shrank the spin-down bandgap of the 3d orbits in the reconstructed CoOOH under the electrochemical activation process,which simultaneously optimized the adsorption and electron conduction of oxygen-related intermediates on Co sites and lowered the OER overpotentials.Our research provides new insights into the methodical planning of the creation of transition-metal oxyhydroxide OER catalysts. 展开更多
关键词 ELECTROCATALYST in situ Raman Mo-doped CoOOH oxygen evolution reaction
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Genesis of the Nuri Cu-W-Mo Deposit,Tibet,China:Constraints from in situ Trace Elements and Sr Isotopic Analysis of Scheelite 被引量:1
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作者 WANG Yiyun WU Zhishan +8 位作者 CHEN Wenqing DU Qing’an TANG Liwei SHI Hongzhao MA Guotao ZHANG Zhi LIANG Wei WU Bo MIAO Hengyi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第1期117-131,共15页
The Nuri deposit is the only Cu-W-Mo polymetallic deposit with large-scale WO3 resources in the eastern section of the Gangdese metallogenic belt,Tibet,China.However,the genetic type of this deposit has been controver... The Nuri deposit is the only Cu-W-Mo polymetallic deposit with large-scale WO3 resources in the eastern section of the Gangdese metallogenic belt,Tibet,China.However,the genetic type of this deposit has been controversial since its discovery.Based on a study of the geological characteristics of the deposit,this study presents mineralization stages,focusing on the oxide stage and the quartz-sulfide stage where scheelite is mainly formed,referred to as Sch-A and Sch-B,respectively.Through LA-ICP-MS trace element and Sr isotope analyses,the origin,evolutionary process of the oreforming fluid and genesis of the ore deposit are investigated.Scanning Electron Microscope-Cathodoluminescence(SEMCL)observations reveal that Sch-A consists of three generations,with dark gray homogenous Sch-A1 being replaced by relatively lighter and homogeneous Sch-A2 and Sch-A3,with Sch-A2 displaying a gray CL image color with vague and uneven growth bands and Sch-A3 has a light gray CL image color with hardly any growth band.In contrast,Sch-B exhibits a‘core-rim’structure,with the core part(Sch-B1)being dark gray and displaying a uniform growth band,while the rim part(Sch-B2)is light gray and homogeneous.The normalized distribution pattern of rare earth elements in scheelite and Sr isotope data suggest that the early ore-forming fluid in the Nuri deposit originated from granodiorite porphyry and,later on,some country rock material was mixed in,due to strong water-rock interaction.Combining the O-H isotope data further indicates that the ore-forming fluid in the Nuri deposit originated from magmatic-hydrothermal sources,with contributions from metamorphic water caused by water-rock interaction during the mineralization process,as well as later meteoric water.The intense water-rock interaction likely played a crucial role in the precipitation of scheelite,leading to varying Eu anomalies in different generations of scheelite from the oxide stage to the quartz-sulfide stage,while also causing a gradual decrease in oxygen fugacity(fO2)and a slow rise in pH value.Additionally,the high Mo and low Sr contents in the scheelite are consistent with typical characteristics of magmatic-hydrothermal scheelite.Therefore,considering the geological features of the deposit,the geochemical characteristics of scheelite and the O-H isotope data published previously,it can be concluded that the genesis of the Nuri deposit belongs to porphyry-skarn deposit. 展开更多
关键词 trace elements in situ Sr isotopes tungsten mineralization Gangdese metallogenic belt TIBET
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Development of in situ characterization techniques in molecular beam epitaxy 被引量:1
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作者 Chao Shen Wenkang Zhan +7 位作者 Manyang Li Zhenyu Sun Jian Tang Zhaofeng Wu Chi Xu Bo Xu Chao Zhao Zhanguo Wang 《Journal of Semiconductors》 EI CAS CSCD 2024年第3期9-32,共24页
Ex situ characterization techniques in molecular beam epitaxy(MBE)have inherent limitations,such as being prone to sample contamination and unstable surfaces during sample transfer from the MBE chamber.In recent years... Ex situ characterization techniques in molecular beam epitaxy(MBE)have inherent limitations,such as being prone to sample contamination and unstable surfaces during sample transfer from the MBE chamber.In recent years,the need for improved accuracy and reliability in measurement has driven the increasing adoption of in situ characterization techniques.These techniques,such as reflection high-energy electron diffraction,scanning tunneling microscopy,and X-ray photoelectron spectroscopy,allow direct observation of film growth processes in real time without exposing the sample to air,hence offering insights into the growth mechanisms of epitaxial films with controlled properties.By combining multiple in situ characterization techniques with MBE,researchers can better understand film growth processes,realizing novel materials with customized properties and extensive applications.This review aims to overview the benefits and achievements of in situ characterization techniques in MBE and their applications for material science research.In addition,through further analysis of these techniques regarding their challenges and potential solutions,particularly highlighting the assistance of machine learning to correlate in situ characterization with other material information,we hope to provide a guideline for future efforts in the development of novel monitoring and control schemes for MBE growth processes with improved material properties. 展开更多
关键词 epitaxial growth thin film in situ characterization molecular beam epitaxy(MBE)
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Suppressed Internal Intrinsic Stress Engineering in High-Performance Ni-Rich Cathode Via Multi layered In Situ Coating Structure 被引量:1
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作者 Jiachao Yang Yunjiao Li +3 位作者 Xiaoming Xi Junchao Zheng Jian Yu Zhenjiang He 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期58-66,共9页
LiNi_(x)Co_(y)Al_(z)O_(2)(NCA)cathode materials are drawing widespread attention,but the huge gap between the ideal and present cyclic stability still hinders their further commercial application,especially for the Ni... LiNi_(x)Co_(y)Al_(z)O_(2)(NCA)cathode materials are drawing widespread attention,but the huge gap between the ideal and present cyclic stability still hinders their further commercial application,especially for the Ni-rich LiNi_(x)Co_(y)Al_(z)O_(2)(x>0.8,x+y+z=1)cathode material,which is owing to the structural degradation and particles'intrinsic fracture.To tackle the problems,Li_(0.5)La_(2)Al_(0.5)O_(4)in situ coated and Mn compensating doped multilayer LiNi_(0.82)Co_(0.14)Al_(0.04)O_(2)was prepared.XRD refinement indicates that La-Mn co-modifying could realize appropriate Li/Ni disorder degree.Calculated results and in situ XRD patterns reveal that the LLAO coating layer could effectively restrain crack in secondary particles benefited from the suppressed internal strain.AFM further improves as NCA-LM2 has superior mechanical property.The SEM,TEM,XPS tests indicate that the cycled cathode with LLAO-Mn modification displays a more complete morphology and less side reaction with electrolyte.DEMS was used to further investigate cathode-electrolyte interface which was reflected by gas evolution.NCA-LM2 releases less CO_(2)than NCA-P indexing on a more stable surface.The modified material presents outstanding capacity retention of 96.2%after 100 cycles in the voltage range of 3.0-4.4 V at 1C,13%higher than that of the pristine and 80.8%at 1 C after 300 cycles.This excellent electrochemical performance could be attributed to the fact that the high chemically stable coating layer of Li_(0.5)La_(2)Al_(0.5)O_(4)(LLAO)could enhance the interface and the Mn doping layer could suppress the influence of the lattice mismatch and distortion.We believe that it can be a useful strategy for the modification of Ni-rich cathode material and other advanced functional material. 展开更多
关键词 compensating doped in situ coating multilayer material Ni-rich cathode materials suppressed internal strain
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Numerical study of plasmas start-up by electron cyclotron waves in NCST spherical tokamak and CN-H1 stellarator
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作者 刘亿卓行 郑平卫 +4 位作者 龚学余 尹岚 陈小昌 钟翊君 杨文军 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第7期12-22,共11页
According to the physics of tokamak start-up,this study constructs a zero-dimensional(0D)model applicable to electron cyclotron(EC)wave assisted start-up in NCST spherical torus(spherical tokamak)and CN-H1 stellarator... According to the physics of tokamak start-up,this study constructs a zero-dimensional(0D)model applicable to electron cyclotron(EC)wave assisted start-up in NCST spherical torus(spherical tokamak)and CN-H1 stellarators.Using the constructed 0D model,the results obtained in this study under the same conditions are compared and validated against reference results for pure hydrogen plasma start-up in tokamak.The results are in good agreement,especially regarding electron temperature,ion temperature and plasma current.In the presence of finite Ohmic electric field in the spherical tokamak,a study on the EC wave assisted start-up of the NCST plasma at frequency of 28 GHz is conducted.The impact of the vertical magnetic field B_(v)on EC wave assisted start-up,the relationship between EC wave injection power P_(inj),Ohmic electric field E,and initial hydrogen atom density n_(H0)are explored separately.It is found that under conditions of Ohmic electric field lower than ITER(~0.3 V m^(-1)),EC wave can expand the operational space to achieve better plasma parameters.Simulating the process of28 GHz EC wave start-up in the CN-H1 stellarator plasma,the plasma current in the zerodimensional model is replaced with the current in the poloidal coil of the stellarator.Plasma startup can be successfully achieved at injection powers in the hundreds of kilowatts range,resulting in electron densities on the order of 10^(17)-10^(18)m^(-3). 展开更多
关键词 spherical torus STELLARATOR electron cyclotron wave start-up 0D model
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Lunar In Situ Large-Scale Construction:Quantitative Evaluation of Regolith Solidification Techniques
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作者 Charun Bao Daobo Zhang +2 位作者 Qinyu Wang Yifei Cui Peng Feng 《Engineering》 SCIE EI CAS CSCD 2024年第8期204-221,共18页
Lunar habitat construction is crucial for successful lunar exploration missions.Due to the limitations of transportation conditions,extensive global research has been conducted on lunar in situ material processing tec... Lunar habitat construction is crucial for successful lunar exploration missions.Due to the limitations of transportation conditions,extensive global research has been conducted on lunar in situ material processing techniques in recent years.The aim of this paper is to provide a comprehensive review,precise classification,and quantitative evaluation of these approaches,focusing specifically on four main approaches:reaction solidification(RS),sintering/melting(SM),bonding solidification(BS),and confinement formation(CF).Eight key indicators have been identified for the construction of low-cost and highperformance systems to assess the feasibility of these methods:in situ material ratio,curing temperature,curing time,implementation conditions,compressive strength,tensile strength,curing dimensions,and environmental adaptability.The scoring thresholds are determined by comparing the construction requirements with the actual capabilities.Among the evaluated methods,regolith bagging has emerged as a promising option due to its high in situ material ratio,low time requirement,lack of hightemperature requirements,and minimal shortcomings,with only the compressive strength falling below the neutral score.The compressive strength still maintains a value of 2–3 MPa.The proposed construction scheme utilizing regolith bags offers numerous advantages,including rapid and large-scale construction,ensured tensile strength,and reduced reliance on equipment and energy.In this study,guidelines for evaluating regolith solidification techniques are provided,and directions for improvement are offered.The proposed lunar habitat design based on regolith bags is a practical reference for future research. 展开更多
关键词 Lunar habitats Lunar in situ construction Regolith bag Solidification and formation In situ materials Evaluation method
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Analytical investigations of in situ stress inversion from borehole breakout geometries
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作者 Zizhuo Xiang Taehyun Moon +2 位作者 Joung Oh Guangyao Si Ismet Canbulat 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第7期2375-2387,共13页
This study aims to investigate the feasibility of deriving in situ horizontal stresses from the breakout width and depth using the analytical method.Twenty-three breakout data with different borehole sizes were collec... This study aims to investigate the feasibility of deriving in situ horizontal stresses from the breakout width and depth using the analytical method.Twenty-three breakout data with different borehole sizes were collected and three failure criteria were studied.Based on the Kirsch equations,relatively accurate major horizontal stress(sH)estimations from known minor horizontal stress(sh)were achieved with percentage errors ranging from 0.33%to 44.08%using the breakout width.The Mogi-Coulomb failure criterion(average error:13.1%)outperformed modified Wiebols-Cook(average error:19.09%)and modified Lade(average error:18.09%)failure criteria.However,none of the tested constitutive models could yield reasonable sh predictions from known sH using the same approach due to the analytical expression of the redistributed stress and the nature of the constitutive models.In consideration of this issue,the horizontal stress ratio(sH/sh)is suggested as an alternative input,which could estimate both sH and sh with the same level of accuracy.Moreover,the estimation accuracies for both large-scale and laboratory-scale breakouts are comparable,suggesting the applicability of this approach across different breakout sizes.For breakout depth,conformal mapping and complex variable method were used to calculate the stress concentration around the breakout tip,allowing the expression of redistributed stresses using binomials composed of sH and sh.Nevertheless,analysis of the breakout depth stabilisation mechanism indicates that additional parameters are required to utilise normalised breakout depth for stress estimation compared to breakout width.These parameters are challenging to obtain,especially under field conditions,meaning utilising normalised breakout depth analytically in practical applications faces significant challenges and remains infeasible at this stage.Nonetheless,the normalised breakout depth should still be considered a critical input for any empirical and statistical stress estimation method given its significant correlation with horizontal stresses.The outcome of this paper is expected to contribute valuable insights into the breakout stabilisation mechanisms and estimation of in situ stress magnitudes based on borehole breakout geometries. 展开更多
关键词 Borehole failure In situ stress estimation In situ horizontal stress ratio Conformal mapping Complex variable method Breakout stabilisation
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In situ formation of an intimate solid-solid interface by reaction between MgH_(2) and Ti to stabilize metal hydride anode with high active material content
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作者 Yixin Chen Atsushi Inoishi +2 位作者 Shigeto Okada Hikari Sakaebe Ken Albrecht 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第8期3193-3203,共11页
MgH_(2) and TiH_(2) have been extensively studied as potential anode materials due to their high theoretical specific capacities of 2036 and 1024 mAh/g,respectively.However,the large volume changes that these compound... MgH_(2) and TiH_(2) have been extensively studied as potential anode materials due to their high theoretical specific capacities of 2036 and 1024 mAh/g,respectively.However,the large volume changes that these compounds undergo during cycling affects their performance and limits practical applications.The present work demonstrates a novel approach to limiting the volume changes of active materials.This effect is based on mechanical support from an intimate interface generated in situ via the reaction between MgH_(2) and Ti within the electrode prior to lithiation to form Mg and TiH_(2).The resulting Mg can be transformed back to MgH_(2) by reaction with LiH during delithiation.In addition,the TiH_(2) improves the reaction kinetics of MgH_(2) and enhances electrochemical performance.The intimate interface produced in this manner is found to improve the electrochemical properties of a MgH_(2)-Ti-LiH electrode.An exceptional reversible capacity of 800 mAh/g is observed even after 200 cycles with a high current density of 1 mA/cm^(2) and a high proportion of active material(90 wt.%)at an operation temperature of 120℃.This study therefore showcases a new means of improving the performance of electrodes by limiting the volume changes of active materials. 展开更多
关键词 All-solid-state battery In situ formation of solid electrolyte In situ formed intimate interface MgH_(2)anode
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From small to large-The application of in situ polymerization within tumor cells
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作者 Mingjie Jia Yonghang Liu +1 位作者 Peng Wei Tao Yi 《Aggregate》 EI CAS 2024年第4期33-53,共21页
The“laboratory”of cells has the capacity to polymerize monosaccharides,amino acids,and nucleotides.Tumor cells,characterized by the overexpression of multi-ple enzymes and existing in a slightly acidic and highly re... The“laboratory”of cells has the capacity to polymerize monosaccharides,amino acids,and nucleotides.Tumor cells,characterized by the overexpression of multi-ple enzymes and existing in a slightly acidic and highly redox-potent environment,have attracted the attention of chemists aiming to transfer chemical reactions from the traditional laboratoryflask to this“cellular laboratory”.Polymers,resulting from the repetitive linkage of monomers,have garnered extensive utility in the biomed-icalfield due to their diverse structural and physicochemical properties.When the polymerization reaction proceeds in situ within the tumor cells,this in situ trans-formation from small-to-large combines the rapid uptake of monomeric molecules with the strong retention ability of polymers,exerting a profound impact on drug delivery within tumors.Moreover,it shows promising applications in the regulation of cell behavior,imaging,therapy,and theranostics.Given the diverse functions of in situ polymerization in relation to tumor cells,this review focuses on a comprehen-sive examination of various strategies for in situ polymerization within tumor cells,categorizing these strategies based on the formation mechanisms of polymers.The applications in this domain concerning in situ polymerization within tumor cells are also explored.Moreover,a discussion of specific limitations in current research and insights into potential future directions from the authors’perspective are provided. 展开更多
关键词 in situ POLYMERIZATION tumor cell
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Exploring the Cation Regulation Mechanism for Interfacial Water Involved in the Hydrogen Evolution Reaction by In Situ Raman Spectroscopy
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作者 Xueqiu You Dongao Zhang +4 位作者 Xia‑Guang Zhang Xiangyu Li Jing‑Hua Tian Yao‑Hui Wang Jian‑Feng Li 《Nano-Micro Letters》 SCIE EI CSCD 2024年第3期303-312,共10页
Interfacial water molecules are the most important participants in the hydrogen evolution reaction(HER).Hence,understanding the behavior and role that interfacial water plays will ultimately reveal the HER mechanism.U... Interfacial water molecules are the most important participants in the hydrogen evolution reaction(HER).Hence,understanding the behavior and role that interfacial water plays will ultimately reveal the HER mechanism.Unfortunately,investigating interfacial water is extremely challenging owing to the interference caused by bulk water molecules and complexity of the interfacial environment.Here,the behaviors of interfacial water in different cationic electrolytes on Pd surfaces were investigated by the electrochemistry,in situ core-shell nanostructure enhanced Raman spectroscopy and theoretical simulation techniques.Direct spectral evidence reveals a red shift in the frequency and a decrease in the intensity of interfacial water as the potential is shifted in the positively direction.When comparing the different cation electrolyte systems at a given potential,the frequency of the interfacial water peak increases in the specified order:Li+<Na^(+)<K^(+)<Ca^(2+)<Sr^(2+).The structure of interfacial water was optimized by adjusting the radius,valence,and concentration of cation to form the two-H down structure.This unique interfacial water structure will improve the charge transfer efficiency between the water and electrode further enhancing the HER performance.Therefore,local cation tuning strategies can be used to improve the HER performance by optimizing the interfacial water structure. 展开更多
关键词 In situ Raman Interfacial water Hydrogen evolution reaction CATIONS
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Direct observation of shock-induced phase transformation in polycrystalline iron via in situ x-ray diffraction
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作者 Fan Zhang Jia-Qin Dong +11 位作者 Zhi-Yong Xie Zhi-Yu He Hua Shu Rui-Rong Wang Jun Xiong Guo Jia Zhi-Heng Fang Wei Wang Da-Wu Xiao An-Le Lei Jie Chen Xiu-Guang Huang 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期337-342,共6页
Phase transition of polycrystalline iron compressed along the Hugoniot is studied by combining laser-driven shock with in situ x-ray diffraction technique.It is suggested that polycrystalline iron changes from an init... Phase transition of polycrystalline iron compressed along the Hugoniot is studied by combining laser-driven shock with in situ x-ray diffraction technique.It is suggested that polycrystalline iron changes from an initial body-centered cubic structure to a hexagonal close-packed structure with increasing pressure(i.e.,a phase transition fromαtoε).The relationship between density and pressure for polycrystalline iron obtained from the present experiments is found to be in good agreement with the gas-gun Hugoniot data.Our results show that experiments with samples at lower temperatures under static loading,such as in a diamond anvil cell,lead to higher densities measured than those found under dynamic loading.This means that extrapolating results of static experiments may not predict the dynamic responses of materials accurately.In addition,neither the face-centered cubic structure seen in previous molecular-dynamics simulations or twophase coexistence are found within our experimental pressure range. 展开更多
关键词 in situ x-ray diffraction phase transition polycrystalline iron
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Investigation of an electrode-driven hydrogen plasma method for in situ cleaning of tin-based contamination
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作者 彭怡超 叶宗标 +7 位作者 王思蜀 蒲国 刘显洋 苑聪聪 廖加术 韦建军 余新刚 芶富均 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第8期73-83,共11页
To prolong the service life of optics,the feasibility of in situ cleaning of the multilayer mirror(MLM)of tin and its oxidized contamination was investigated using hydrogen plasma at different power levels.Granular ti... To prolong the service life of optics,the feasibility of in situ cleaning of the multilayer mirror(MLM)of tin and its oxidized contamination was investigated using hydrogen plasma at different power levels.Granular tin-based contamination consisting of micro-and macroparticles was deposited on silicon via physical vapor deposition(PVD).The electrodedriven hydrogen plasma at different power levels was systematically diagnosed using a Langmuir probe and a retarding field ion energy analyzer(RFEA).Moreover,the magnitude of the self-biasing voltage was measured at different power levels,and the peak ion energy was corrected for the difference between the RFEA measurements and the self-biasing voltage(E_(RFEA)-eV_(self)).XPS analysis of O 1s and Sn 3d peaks demonstrated the chemical reduction process after 1 W cleaning.Analysis of surface and cross-section morphology revealed that holes emerged on the upper part of the macroparticles while its bottom remained smooth.Hills and folds appeared on the upper part of the microparticles,confirming the top-down cleaning mode with hydrogen plasma.This study provides an in situ electrode-driven hydrogen plasma etching process for tin-based contamination and will provide meaningful guidance for understanding the chemical mechanism of reduction and etching. 展开更多
关键词 tin-based contamination hydrogen plasma in situ cleaning ion energy
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In Situ Raman Monitoring of Trace Antibiotics in Different Harsh Water Environments
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作者 Chundong Liu Fengcai Lei +6 位作者 Maogang Gong Xiaoming Zhou Xiaofei Zhao Zhen Li Chao Zhang Baoyuan Man Jing Yu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第1期284-293,共10页
In situ surface-enhanced Raman scattering(SERS)is a widely used operando analytical technique,while facing numerous complex factors in applications under aqueous environment,such as low detection sensitivity,poor anti... In situ surface-enhanced Raman scattering(SERS)is a widely used operando analytical technique,while facing numerous complex factors in applications under aqueous environment,such as low detection sensitivity,poor anti-interference capability,etc.,resulting in unreliable detectability.To address these issues,herein a new hydrophobic SERS strategy has been attempted.By comprehensively designing and researching a SERS-active structure of superhydrophobic ZnO/Ag nanowires,we demonstrate that hydrophobicity can not only draw analytes from water onto substrate,but also adjust"hottest spot"from the bottom of the nanowires to the top.As a result,the structure can simultaneously concentrate the dispersed molecules in water and the enhanced electric field in structure into a same zone,while perfecting its own anti-interference ability.The underwater in situ analytical enhancement factor of this platform is as high as 1.67×10^(11),and the operando limited of detection for metronidazole(MNZ)reaches to 10^(-9)M.Most importantly,we also successfully generalized this structure to various real in situ detection scenarios,including on-site detection of MNZ in corrosive urine,real-time warning of wrong dose of MNZ during intravenous therapy,in situ monitoring of MNZ in flowing wastewater with particulate interference,etc.,demonstrating the great application potential of this hydrophobic platform.This work realizes a synergistic promotion for in situ SERS performance under aqueous environment,and also provides a novel view for improving other in situ analytical techniques. 展开更多
关键词 antibiotic detection hydrophobic structure In situ Raman METRONIDAZOLE WETTABILITY
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In situ forming injectable MSC-loaded GelMA hydrogels combined with PD for vascularized sweat gland regeneration
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作者 Enhe Jirigala Bin Yao +11 位作者 Zhao Li Yi-Jie Zhang Chao Zhang Li-Ting Liang Fan-Liang Zhang Xing-Yu Yuan Xian-Lan Duan Wei Song Meng-De Zhang Yi Kong Xiao-Bing Fu Sha Huang 《Military Medical Research》 SCIE CAS CSCD 2024年第1期152-155,共4页
Dear Editor,Three dimensional(3D)bioprinted extracellular matrix(ECM)can be used to provide both biochemical and biophysical cues to direct mesenchymal stem cells(MSCs)differentiation,and then differentiated cells wer... Dear Editor,Three dimensional(3D)bioprinted extracellular matrix(ECM)can be used to provide both biochemical and biophysical cues to direct mesenchymal stem cells(MSCs)differentiation,and then differentiated cells were isolated for implantation in vivo using surgical procedures.However,the reduced cell activity after cell isolation from 3D constructs and low cell retention in injured sites limit its application[1].Methacrylated gelatin(GelMA)hydrogel has the advantage of fast crosslinking,which could resemble complex architectures of tissue construct in vivo[2].Here,we adopted a noninvasive bioprinting procedure to imitate the regenerative microenvironment that could simultaneously direct the sweat gland(SG)and vascular differentiation from MSCs and ultimately promote the replacement of glandular tissue in situ(Fig.1a). 展开更多
关键词 Sweat gland GelMA In situ niche Cell differentiation Tissue incorporation VASCULARIZATION
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Zn Dissolution-Passivation Behavior with ZnO Formation via In Situ Characterizations
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作者 Tanyanyu Wang Masahiro Kunimoto +3 位作者 Masahiro Yanagisawa Masayuki Morita Takeshi Abe Takayuki Homma 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第1期193-200,共8页
In this study,ZnO formation during the dissolution-passivation process of Zn anodes is observed via in situ Raman and optical characterization.The Zn passivation during galvanostatic anodization merely follows the dis... In this study,ZnO formation during the dissolution-passivation process of Zn anodes is observed via in situ Raman and optical characterization.The Zn passivation during galvanostatic anodization merely follows the dissolution-precipitation model,whereas that of potentiodynamic polarization exhibits different behaviors in different potential ranges.Initially,the Zn electrode is gradually covered by a ZnO precipitation film and then undergoes solid-state oxidation at~255 mV.The starting point of solid-state oxidation is well indicated by the abrupt current drop and yellow coloration of the electrode surface.During the pseudo passivation,an intense current oscillation is observed.Further,blink-like color changes between yellow and dark blue are revealed for the first time,implying that the oscillation is caused by the dynamic adsorption and desorption of OH groups.The as-formed ZnOs then experience a dissolution-reformation evolution,during which the crystallinity of the primary ZnO film is improved but the solid-state-formed ZnO layer becomes rich in oxygen vacancies.Eventually,oxide densification is realized,contributing to the Zn passivation.This study provides new insights into the Zn dissolution-passivation behavior,which is critical for the future optimization of Zn batteries. 展开更多
关键词 in situ characterization Zn dissolution and passivation ZnO formation
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Dynamic in situ reconstruction of NiSe_(2) promoted by interfacial Ce_(2)(CO_(3))_(2)O for enhanced water oxidation
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作者 Fengli Wei Jinghao Shen +6 位作者 Jiayin Xie Zuyang Luo Luyan Shi Tayirjan Taylor Isimjan Xiulin Yang Jieshan Qiu Bin Wu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第11期472-480,共9页
Understanding and manipulating the structural evolution of water oxidation electrocatalysts lays the foundation to finetune their catalytic activity.Herein,we present a synthesis of NiSe_(2)-Ce_(2)(CO_(3))_(2)O hetero... Understanding and manipulating the structural evolution of water oxidation electrocatalysts lays the foundation to finetune their catalytic activity.Herein,we present a synthesis of NiSe_(2)-Ce_(2)(CO_(3))_(2)O heterostructure and demonstrate the efficacy of interfacial Ce_(2)(CO_(3))2O in promoting the formation of catalytically active centers to improve oxygen evolution activity.In-situ Raman spectroscopy shows that incorporation of Ce_(2)(CO_(3))2O into NiSe_(2) causes a cathodic shift of the Ni^(2+)→Ni~(3+) transition potential.Operando electrochemical impedance spectroscopy reveals that strong electronic coupling at heterogeneous interface accelerates charge transfer process.Furthermore,density functional theory calculations suggest that actual catalytic active species of NiOOH transformed from NiSe_(2),which is coupled with Ce_(2)(CO_(3))_(2)O,can optimize electronic structure and decrease the free energy barriers toward fast oxygen evolution reaction(OER) kinetics.Consequently,the resultant NiSe_(2)-Ce_(2)(CO_(3))_(2)O electrode exhibits remarkable electrocatalytic performance with low overpotentials(268/304 mV@50/100 mA cm^(-2)) and excellent stability(50 mA cm^(-2) for 120 h) in the alkaline electrolyte.This work emphasizes the significance of modulating the dynamic changes in developing efficient electrocatalyst. 展开更多
关键词 Dynamic reconstruction Oxygen evolution reaction HETEROSTRUCTURE In situ characterization Density functional theory
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Application of multidisciplinary in situ simulation training in the treatment of acute ischemic stroke: a quality improvement project
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作者 Ganying Huang Huijie Yang +5 位作者 Huan Yao Xinxin Fan Wenqin Xia Yuansheng Xu Xiaoling Shen Xue Zhao 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2024年第1期41-46,共6页
BACKGROUND:Ischemic stroke refers to a disorder in the blood supply to a local area of brain tissue for various reasons and is characterized by high morbidity,mortality,and disability.Early reperfusion of brain tissue... BACKGROUND:Ischemic stroke refers to a disorder in the blood supply to a local area of brain tissue for various reasons and is characterized by high morbidity,mortality,and disability.Early reperfusion of brain tissue at risk of injury is crucial for the treatment of acute ischemic stroke.The purpose of this study was to evaluate comfort levels in managing acute stroke patients with hypoxemia who required endotracheal intubation after multidisciplinary in situ simulation training and to shorten the door-to-image time.METHODS:This quality improvement project utilized a comprehensive multidisciplinary in situ simulation exercise.A total of 53 participants completed the two-day in situ simulation training.The main outcome was the self-reported comfort levels of participants in managing acute stroke patients with hypoxemia requiring endotracheal intubation before and after simulation training.A 5-point Likert scale was used to measure participant comfort.A paired-sample t-test was used to compare the mean self-reported comfort scores of participants,as well as the endotracheal intubation time and door-to-image time on the fi rst and second days of in situ simulation training.The door-to-image time before and after the training was also recorded.RESULTS:The findings indicated that in situ simulation training could enhance participant comfort when managing acute stroke patients with hypoxemia who required endotracheal intubation and shorten door-to-image time.For the emergency management of hypoxemia or tracheal intubation,the mean post-training self-reported comfort score was signifi cantly higher than the mean pre-training comfort score(hypoxemia:4.53±0.64 vs.3.62±0.69,t=-11.046,P<0.001;tracheal intubation:3.98±0.72 vs.3.43±0.72,t=-6.940,P<0.001).We also observed a decrease in the tracheal intubation and door-to-image time and a decreasing trend in the door-to-image time,which continued after the training.CONCLUSION:Our study demonstrates that the implementation of in situ simulation training in a clinical environment with a multidisciplinary approach may improve the ability and confi dence of stroke team members,optimize the fi rst-aid process,and eff ectively shorten the door-to-image time of stroke patients with emergency complications. 展开更多
关键词 Ischemic stroke Endotracheal intubation Door-to-image time In situ simulation Multidisciplinary approach
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Preliminary research and scheme design of deep underground in situ geo-information detection experiment for Geology in Time
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作者 Heping Xie Ru Zhang +13 位作者 Zetian Zhang Yinshuang Ai Jianhui Deng Yun Chen Yong Zhou Mingchuan Li Liqiang Liu Mingzhong Gao Zeqian Yang Weiqiang Ling Heng Gao Qijun Hao Kun Xiao Chendi Lou 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第1期1-13,共13页
The deep earth,deep sea,and deep space are the main parts of the national“three deep”strategy,which is in the forefront of the strategic deployment clearly defined in China’s 14th Five-Year Plan(2021-2025)and the L... The deep earth,deep sea,and deep space are the main parts of the national“three deep”strategy,which is in the forefront of the strategic deployment clearly defined in China’s 14th Five-Year Plan(2021-2025)and the Long-Range Objectives Through the Year 2035.It is important to reveal the evolutionary process and mechanism of deep tectonics to understand the earth’s past,present and future.The academic con-notation of Geology in Time has been given for the first time,which refers to the multi-field evolution response process of geological bodies at different time and spatial scales caused by geological processes inside and outside the Earth.Based on the deep in situ detection space and the unique geological envi-ronment of China Jinping Underground Laboratory,the scientific issue of the correlation mechanism and law between deep internal time-varying and shallow geological response is given attention.Innovative research and frontier exploration on deep underground in situ geo-information detection experiments for Geology in Time are designed to be carried out,which will have the potential to explore the driving force of Geology in Time,reveal essential laws of deep earth science,and explore innovative technologies in deep underground engineering. 展开更多
关键词 Deep underground Geology in Time China Jinping Underground Laboratory In situ detection
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