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Improved equation of state model for the phase behavior of CO_(2)-hydrocarbon coupling nanopore confinements 被引量:1
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作者 Yuan Zhang Zijing Niu +1 位作者 Fangfang Yang Zhanwei Ma 《Natural Gas Industry B》 2025年第3期316-327,共12页
In shale reservoirs,fluids are often confined within nanopores,leading to apparent effects on the properties and phase behavior of the fluid.However,previous studies have primarily focused on the effect of capillary p... In shale reservoirs,fluids are often confined within nanopores,leading to apparent effects on the properties and phase behavior of the fluid.However,previous studies have primarily focused on the effect of capillary pressure or adsorption on well performance,and only a very limited number of studies have researched the complex and coupled impact of confinement on capillarity,adsorption,and interactions between fluid molecules and pore walls.Therefore,in this study,an effective method is developed for evaluating the coupled effects of nanopore confinement on CO_(2) injection performance.First,a comprehensive thermodynamic model that incorporates adsorption,capillary pressure,and molecule-wall interaction in nanopores by modifying the Peng-Robinson equation of state(PR-EOS)is proposed.Subsequently,the calculated critical properties of different components are validated against experimental measured data,illustrating that the developed model can accurately predict the properties of the components of CO_(2)-hydrocarbon systems.Numerical simulations of field-scale case studies were then performed and calibrated using a modified phase equilibrium model.Typical fluid properties were inputted to investigate the effect of nanopore confinement on the CO_(2) injection performance.The results of this study show that the ultimate recovery factor increases by approximately 4.61%at a pore size of 10 nm,indicating that nanopore confinement is advantageous to well performance.Light hydrocarbons undergo more intense mass transfer than heavy hydrocarbons.Furthermore,as the pore radius decreased from 100 nm to 10 nm,the CO_(2) storage coefficient increased by 2.8%.The findings of this study deepen the collective understanding of the effect of nanopore confinement on CO_(2) displacement and storage,which has significant field-scale applications. 展开更多
关键词 Nanopore confinement Minimum miscibility pressure Shale formations CO_(2)injection
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Experimental investigations on mechanical performance of rocks under fatigue loads and biaxial confinements 被引量:12
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作者 DU Kun LI Xue-feng +3 位作者 YANG Cheng-zhi ZHOU Jian CHEN Shao-jie MANOJ Khandelwal 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第10期2985-2998,共14页
In this research,a series of biaxial compression and biaxial fatigue tests were conducted to investigate the mechanical behaviors of marble and sandstone under biaxial confinements.Experimental results demonstrate tha... In this research,a series of biaxial compression and biaxial fatigue tests were conducted to investigate the mechanical behaviors of marble and sandstone under biaxial confinements.Experimental results demonstrate that the biaxial compressive strength of rocks under biaxial compression increases firstly,and subsequently decreases with increase of the intermediate principal stress.The fatigue failure characteristics of the rocks in biaxial fatigue tests are functions of the peak value of fatigue loads,the intermediate principal stress and the rock lithology.With the increase of the peak values of fatigue loads,the fatigue lives of rocks decrease.The intermediate principal stress strengthens the resistance ability of rocks to fatigue loads except considering the strength increasing under biaxial confinements.The fatigue lives of rocks increase with the increase of the intermediate principal stress under the same ratio of the fatigue load and their biaxial compressive strength.The acoustic emission(AE)and fragments studies showed that the sandstone has higher ability to resist the fatigue loads compared to the marble,and the marble generated a greater number of smaller fragments after fatigue failure compared to the sandstone.So,it can be inferred that the rock breaking efficiency and rock burst is higher or severer induced by fatigue loading than that induced by monotonous quasi-static loading,especially for hard rocks. 展开更多
关键词 biaxial confinements fatigue loading acoustic emission FRAGMENTS intermediate principal stress
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SELF-ASSEMBLY OF LINEAR TRIBLOCK COPOLYMERS UNDER CYLINDRICAL NANOPORE CONFINEMENTS 被引量:2
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作者 Wen-juan Qiu 李士本 +1 位作者 Yong-yun Ji Lin Xi Zhang 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2013年第1期122-138,共17页
The self-assembly of linear ABC triblock copolymers under cylindrical confinements is investigated in two- dimensional space using the real-space self-consistent field theory. The effects of confinement degrees and pr... The self-assembly of linear ABC triblock copolymers under cylindrical confinements is investigated in two- dimensional space using the real-space self-consistent field theory. The effects of confinement degrees and preferential strengths on the triblock copolymer phase behaviors with special polymer parameters are first considered. On one hand, different confinement degrees cause different phase behaviors in nanopores with the neutral surfaces. Moreover, the strongly preferential surface fields can surpass the confinement degrees and volume fractions in determing the confined phase behaviors. On the other hand, in contrast, confined morphologies are more sensitive to the variations in the A-preferential surface field strength. Subsequently, the incompatibility degrees between different blocks are systematically varied under cylindrical nanopore confinements. Under cylindrical nanopore confinements, the morphologies are very sensitive to the variations in the incompatibility degrees. Meanwhile, nanopore confinements can affect order-disorder and order-order transition points in the bulk. The corresponding free, internal, and entropic energies as well as the order parameters are also quantificationally examined to deeply investigate the confined phase mechanisms, and a number of morphological transitions are confirmed to be of first-order. These findings may guide the design of novel nanostructures based on triblock copolymers by introducing confinements. 展开更多
关键词 Triblock copolymers Cylindrical confinements SELF-ASSEMBLY Self-consistent field theory.
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Analysis Scheme for Density Modulation Experiments to Study Particle Confinements 被引量:1
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作者 K. TANAKA C. MICHAEL +5 位作者 K. KAWANATA T. TOKUZAWAI M. SHOJI K. TOI 高翔 揭银先 《Plasma Science and Technology》 SCIE EI CAS CSCD 2006年第1期65-71,共7页
Density modulation experiments are powerful experimental schemes for the study of particle transport. The diffusion coefficients (D) and convection velocity (V), which cannot be evaluated from the particle balance... Density modulation experiments are powerful experimental schemes for the study of particle transport. The diffusion coefficients (D) and convection velocity (V), which cannot be evaluated from the particle balance in the equilibrium state, can be obtained separately. Further, the estimated values of D and V are determined independent of the absolute value of the particle source rate, which is difficult to obtain experimentally. However, the sensitivities and interpretation of D and V from the modulation experiments need to be considered. This paper describes numerical techniques for solving the particle balance equation of the modulation components. Examples of the analysis are shown regarding the data of LHD experiments, and the results of the modulation experiments are discussed. 展开更多
关键词 density modulation particle confinements diffusion coefficient convection velocity
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Sandwiching Sulfur into the Dents Between N,O Co-Doped Graphene Layered Blocks with Strong Physicochemical Confinements for Stable and High-Rate Li-S Batteries 被引量:6
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作者 Mengjiao Shi Su Zhang +5 位作者 Yuting Jiang Zimu Jiang Longhai Zhang Jin Chang Tong Wei Zhuangjun Fan 《Nano-Micro Letters》 SCIE EI CAS CSCD 2020年第11期13-24,共12页
The development of lithium-sulfur batteries(LSBs)is restricted by their poor cycle stability and rate performance due to the low conductivity of sulfur and severe shuttle effect.Herein,an N,O co-doped graphene layered... The development of lithium-sulfur batteries(LSBs)is restricted by their poor cycle stability and rate performance due to the low conductivity of sulfur and severe shuttle effect.Herein,an N,O co-doped graphene layered block(NOGB)with many dents on the graphene sheets is designed as effective sulfur host for high-performance LSB s.The sulfur platelets are physically confined into the dents and closely contacted with the graphene scaffold,ensuring structural stability and high conductivity.The highly doped N and O atoms can prevent the shuttle effect of sulfur species by strong chemical adsorption.Moreover,the micropores on the graphene sheets enable fast Li^+transport through the blocks.As a result,the obtained NOGB/S composite with 76 wt%sulfur content shows a high capacity of 1413 mAh g^-1 at 0.1 C,good rate performance of 433 mAh g^-1 at 10 C,and remarkable stability with 526 mAh g^-1 at after 1000 cycles at 1 C(average decay rate:0.038%per cycle).Our design provides a comprehensive route for simultaneously improving the conductivity,ion transport kinetics,and preventing the shuttle effect in LSBs. 展开更多
关键词 GRAPHENE Physicochemical confinement Cycle stability Shuttle effect Li-S batteries
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A novel spoof surface plasmon polariton structure to reach ultra-strong field confinements 被引量:4
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作者 Pei Hang He Hao Chi Zhang +5 位作者 Xinxin Gao Ling Yun Niu Wen Xuan Tang Jiayuan Lu Le Peng Zhang Tie Jun Cui 《Opto-Electronic Advances》 2019年第6期9-15,共7页
Ultrathin corrugated metallic structures have been proved to support spoof surface plasmon polariton (SPP) modes on two-dimension (2D) planar microwave circuits.However,to provide stronger field confinement,larger wid... Ultrathin corrugated metallic structures have been proved to support spoof surface plasmon polariton (SPP) modes on two-dimension (2D) planar microwave circuits.However,to provide stronger field confinement,larger width of strip is required to load deeper grooves,which is cumbersome in modern large-scale integrated circuits and chips.In this work,a new spoof SPP transmission line (TL) with zigzag grooves is proposed.This new structure can achieve stronger field confinement compared to conventional one with the same strip width.In other words,the proposed spoof SPP TL behaves equivalently to a conventional one with much larger size.Dispersion analysis theoretically indicates the negative correlation between the ability of field confinement and cutoff frequencies of spoof SPP TLs.Numerical simulations indicate that the cutoff frequency of the proposed TL is lower than the conventional one and can be easily modified with the fixed size.Furthermore,two samples of the new and conventional spoof SPP TLs are fabricated for experimental demonstration.Measured S-parameters and field distributions verify the ultra-strong ability of field confinement of the proposed spoof SPP TL.Hence,this novel spoof SPP structure with ultra-strong field confinement may find wide applications in microwave and terahertz engineering. 展开更多
关键词 ULTRATHIN corrugated metallic STRUCTURE surface PLASMON POLARITONS field confinement ZIGZAG GROOVES
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The Dendritic Cells’ Immunological Behaviors Modulated by the Spatial Confinements of Deposited Fibrin Matrix
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作者 Wenhui Hu Yun Wang +3 位作者 Jin Chen Yonggang Song Jinhua Long Zhu Zeng 《医用生物力学》 EI CAS CSCD 北大核心 2019年第A01期139-140,共2页
Implant materials,as foreign objects to host,can cause various degrees of inflammation in most cases.The inflammation is triggered by a series of immune responses and directly impacts the tissue regeneration process,w... Implant materials,as foreign objects to host,can cause various degrees of inflammation in most cases.The inflammation is triggered by a series of immune responses and directly impacts the tissue regeneration process,which determines the outcome of tissue repair.The immune responses are complex process involving numerous immune cells and can be divide into innate immune and adaptive immune responses.Once materials are implanted,innate immune responses are activated under the mediation of several immune cells(e.g.neutrophils and macrophages),meanwhile immature dendritic cells(imDCs)are recruited to the implant sites to recognize,internalize and process antigens.Upon antigen uptake,imDCs gradually differentiate into mature dendritic cells(mDCs)and migrate to secondary lymph nodes.In the lymph nodes,mDCs present processed antigen peptides to naive T lymphocytes and activate their antigen specific proliferation,resulting in initiation of adaptive immune responses.Due to their key position in the immune system,serving to bridge innate and adaptive immunity,DCs are crucial to guiding and modulating the immune responses caused by implanted materials.Therefore,figuring out the response of DCs to implanted materials and the exact role of DCs in tissue healing processes will provide deeper insight for the rational design of biomaterials.Previous studies on the effects of implants on immune functions of DCs are mainly focused on physical and chemical properties of the materials(e.g.released chemical composition,surface chemistry,substrate stiffness and surface topography).All these factors will change the microenvironment of the tissue around implant materials,which affect the immune functions of DCs.However,the change of microenvironment not only directly derives from the physical and chemical properties of the material(intrinsic),but also indirectly results from the remodeled extracellular matrix(ECM)caused by implanted materials.When blood or tissue fluid contact with materials after implantation,proteins(e.g.fibrin and collagen)will absorb and deposit on the surface of implants,leading to a provisionally stable matrix with microporous fibrous-liked network structure.It means that the remodeled ECM can provide adhesion sites for recruited DCs and form spatial confinement.DCs,as a kind of cells that are extremely sensitive to mechanical stimuli,theoretically,can response to the mechanical stimuli coming from spatial confinement of remodeled ECM,which may lead to a series of modulations in their cell morphologies and immune functions.Then,the remodeled ECM is a non-negligible mechanical cue.However,to the best of our knowledge,there is a lack of a simple and effective model to establish the relationship between the immune functions of DCs and remodeled ECM.Most studies on the responses of DCs to implanted materials are still based on suspension culture model,which is the normal status of DCs in vitro culture systems.In addition,the processes by which DC exerts immune functions(both endocytosis and antigen presentation)are dynamically physical interaction.It means that the changes of DCs’immune functions are highly correlated with the changes of their biomechanical characteristics caused by remodeled ECM.In this work,we have found that the ECM was remodeled by a large amount of fibrin matrix deposited on the surface of implants in the early stage of the inflammations following implantation.Thus,we used non-toxic salmon fibrin hydrogels with microporous fibrous-liked network structure to mimic the deposited fibrin matrix.Then,human monocyte-derived DCs were cultured on the surface and inside of the fibrin hydrogels to mimic the different spatial confinement states of fibrin matrix.Our results indicated that cell morphologies and cytoskeleton structures of DCs were regulated by the spatial confinement of fibrin hydrogels,resulting in generating mechanical stimuli for DCs.Furthermore,we have found that the biomechanical characteristics and the immune functions of both imDCs and mDC were also modulated.Considering the changes in surface markers,secreted cytokines and biomechanical characteristics of DCs,it indicates that the tendency and magnitude of modulations were highly associated with the spatial confinement of fibrin hydrogels.This model demonstrated that mechanical stimuli deriving from spatial confinement of deposited fibrin matrix is an important factor for regulating the biomechanical characteristics and immune functions of DCs. 展开更多
关键词 DENDRITIC cells FIBRIN matrix spatial CONFINEMENT mechanical stimuli IMMUNE functions
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Effects of electrostatic interactions and geometrical confinements on depletion interactions in charged colloidal system
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作者 黄立新 肖长明 +1 位作者 胡苹 高海峡 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第3期1287-1293,共7页
In a charged colloidal system, the influence on depletion interaction between two like-charged macro-ions is studied through Monte Carlo simulation in this paper. The numerical results show that this depletion force i... In a charged colloidal system, the influence on depletion interaction between two like-charged macro-ions is studied through Monte Carlo simulation in this paper. The numerical results show that this depletion force is affected by both the electrostatic interactions between charged spheres and charged plates and by the geometrical factor of the two charged plates, and they further indicate that the influence of geometrical confinement on the depletion interaction is larger than that of electrostatic potential. 展开更多
关键词 depletion interaction geometrical confinement
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Micro/Nano‑Reconfigurable Robots for Intelligent Carbon Management in Confined‑Space Life‑Support Systems
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作者 Wei Lu Rimei Chen +5 位作者 Lianlong Zhan Qin Xiang Renting Huang Lei Wang Shuangfei Wang Hui He 《Nano-Micro Letters》 2026年第3期210-226,共17页
Strategically coupling nanoparticle hybrids and internal thermosensitive molecular switches establishes an innovative paradigm for constructing micro/nanoscale-reconfigurable robots,facilitating energyefficient CO_(2)... Strategically coupling nanoparticle hybrids and internal thermosensitive molecular switches establishes an innovative paradigm for constructing micro/nanoscale-reconfigurable robots,facilitating energyefficient CO_(2) management in life-support systems of confined space.Here,a micro/nano-reconfigurable robot is constructed from the CO_(2) molecular hunters,temperature-sensitive molecular switch,solar photothermal conversion,and magnetically-driven function engines.The molecular hunters within the molecular extension state can capture 6.19 mmol g^(−1) of CO_(2) to form carbamic acid and ammonium bicarbonate.Interestingly,the molecular switch of the robot activates a molecular curling state that facilitates CO_(2) release through nano-reconfiguration,which is mediated by the temperature-sensitive curling of Pluronic F127 molecular chains during the photothermal desorption.Nano-reconfiguration of robot alters the amino microenvironment,including increasing surface electrostatic potential of the amino group and decreasing overall lowest unoccupied molecular orbital energy level.This weakened the nucleophilic attack ability of the amino group toward the adsorption product derivatives,thereby inhibiting the side reactions that generate hard-to-decompose urea structures,achieving the lowest regeneration temperature of 55℃ reported to date.The engine of the robot possesses non-contact magnetically-driven micro-reconfiguration capability to achieve efficient photothermal regeneration while avoiding local overheating.Notably,the robot successfully prolonged the survival time of mice in the sealed container by up to 54.61%,effectively addressing the issue of carbon suffocation in confined spaces.This work significantly enhances life-support systems for deep-space exploration,while stimulating innovations in sustainable carbon management technologies for terrestrial extreme environments. 展开更多
关键词 Micro/nano RECONFIGURABLE Robot Confined space CO_(2)management Efficient regeneration
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An Ultrasonic Microrobot Enabling Ultrafast Bidirectional Navigation in Confinned Tubular Environments
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作者 Meng Cui Liyun Zhen +5 位作者 Xingyu Bai Lihan Yu Xuhao Chen Jingquan Liu Qingkun Liu Bin Yang 《Nano-Micro Letters》 2026年第2期183-198,共16页
Pipelines are extensively used in environments such as nuclear power plants,chemical factories,and medical devices to transport gases and liquids.These tubular environments often feature complex geometries,confined sp... Pipelines are extensively used in environments such as nuclear power plants,chemical factories,and medical devices to transport gases and liquids.These tubular environments often feature complex geometries,confined spaces,and millimeter-scale height restrictions,presenting significant challenges to conventional inspection methods.Here,we present an ultrasonic microrobot(weight,80 mg;dimensions,24 mm×7 mm;thickness,210μm)to realize agile and bidirectional navigation in narrow pipelines.The ultrathin structural design of the robot is achieved through a high-performance piezoelectric composite film microstructure based on MEMS technology.The robot exhibits various vibration modes when driven by ultrasonic frequency signals,its motion speed reaches81 cm s-1 at 54.8 k Hz,exceeding that of the fastest piezoelectric microrobots,and its forward and backward motion direction is controllable through frequency modulation,while the minimum driving voltage for initial movement can be as low as 3 VP-P.Additionally,the robot can effortlessly climb slopes up to 24.25°and carry loads more than 36 times its weight.The robot is capable of agile navigation through curved L-shaped pipes,pipes made of various materials(acrylic,stainless steel,and polyvinyl chloride),and even over water.To further demonstrate its inspection capabilities,a micro-endoscope camera is integrated into the robot,enabling real-time image capture inside glass pipes. 展开更多
关键词 Ultrasonic microrobot Piezoelectric composite film microstructure MEMS fabrication Bidirectional locomotion Confined pipeline inspection
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Compact modeling of quantum confinements in nanoscale gate-all-around MOSFETs
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作者 Baokang Peng Yanxin Jiao +7 位作者 Haotian Zhong Zhao Rong Zirui Wang Ying Xiao Waisum Wong Lining Zhang Runsheng Wang Ru Huang 《Fundamental Research》 CAS CSCD 2024年第5期1306-1313,共8页
In this work,a surface-potential based compact model focusing on the quantum confinement effects of ultimately scaled gate-all-around(GAA)MOSFET is presented.Energy quantization with sub-band formation along the radiu... In this work,a surface-potential based compact model focusing on the quantum confinement effects of ultimately scaled gate-all-around(GAA)MOSFET is presented.Energy quantization with sub-band formation along the radius direction of cylindrical GAAs or thickness direction of nanosheet GAAs leads to significant quantization effects.An analytical model of surface potentials is developed by solving the Poisson equation with incorporating sub-band effects.In combination with the existing transport model framework,charge-voltage and current-voltage formulations are developed based on the surface potential.The model formulations are then extensively validated using TCAD numerical simulations as well as Si data of nanosheet GAA MOSFETs.Simulations of typical circuits verify the model robustness and convergence for its applications in GAA technology. 展开更多
关键词 Gate-all-around FET Compact model Quantum mechanical confinement Nanosheet FET Nanowire FET Sub-band energy
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Hybrid AlGaInAs/Si Fabry–Pérot lasers with near-total mode confinements
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作者 Yuede Yang Shaoshuai Sui +4 位作者 Mingying Tang Jinlong Xiao Yun Du Andrew W.Poon Yongzhen Huang 《Journal of Semiconductors》 EI CAS CSCD 2018年第8期41-46,共6页
We have proposed and demonstrated hybrid Al Ga In As/Si Fabry–Pérot(FP) lasers, with the FP cavity facet covered by the p-electrode metal for enhancing mode confinement. Continuous-wave lasing is obtained at roo... We have proposed and demonstrated hybrid Al Ga In As/Si Fabry–Pérot(FP) lasers, with the FP cavity facet covered by the p-electrode metal for enhancing mode confinement. Continuous-wave lasing is obtained at room temperature with a threshold current of 45 m A for the hybrid FP laser with a cavity length of 415 μm and a width of 7 μm. Near-field optical microscope images indicate an efficient output emission from the underneath evanescently-coupled silicon waveguide. Furthermore, single-mode lasing with a side-mode suppression-ratio of29 d B and a threshold current of 16 m A is realized for the 150 μm-long hybrid FP laser. 展开更多
关键词 hybrid AlGaInAs/Si laser Fabry–Pérot cavity mode Q factor metal confinement
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Advances in iron-based Fischer-Tropsch synthesis with high carbon efficiency 被引量:1
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作者 Xueqing Zhang Wusha Jiye +2 位作者 Yuhua Zhang Jinlin Li Li Wang 《Chinese Journal of Catalysis》 2025年第7期4-21,共18页
Fischer-Tropsch synthesis offers a promising route to convert carbon-rich resources such as coal,natural gas,and biomass into clean fuels and high-value chemicals via syngas.Catalyst development is crucial for optimiz... Fischer-Tropsch synthesis offers a promising route to convert carbon-rich resources such as coal,natural gas,and biomass into clean fuels and high-value chemicals via syngas.Catalyst development is crucial for optimizing the process,with cobalt-and iron-based catalysts being widely used in industrial applications.Iron-based catalysts,in particular,are favored due to their low cost,broad temperature range,and high water-gas shift reaction activity,making them ideal for syngas derived from coal and biomass with a low H_(2)/CO ratio.However,despite their long history of industrial use,iron-based catalysts face two significant challenges.First,the presence of multiple iron phases-metallic iron,iron oxides,and iron carbides-complicates the understanding of the reaction mechanism due to dynamic phase transformations.Second,the high water-gas shift activity of these catalysts leads to increased CO_(2) selectivity,thereby reducing overall carbon efficiency.In Fischer-Tropsch synthesis,CO_(2) can arise as primary CO_(2) from CO disproportionation(the Boudouard reaction)and as secondary CO_(2) from the water-gas shift reaction.The accumulation of CO_(2) formation further compromises overall carbon efficiency,which is particularly undesirable given the current focus on minimizing carbon emissions and achieving carbon neutrality.This review focus on the ongoing advancements of iron-based catalysts for Fischer-Tropsch synthesis,with particular emphasis on overcoming these two critical challenges for iron-based catalysts:regulating the active phases and minimizing CO_(2) selectivity.Addressing these challenges is essential for enhancing the overall catalytic efficiency and selectivity of iron-based catalysts.In this review,recent efforts to suppress CO_(2) selectivity of iron-based catalysts,including catalyst hydrophobic modification and graphene confinement,are explored for their potential to stabilize active phases and prevent unwanted side reactions.This innovative approach offers new opportunities for developing catalysts with high activity,low CO_(2) selectivity,and enhanced stability,which are key factors for enhancing both the efficiency and sustainability for Fischer-Tropsch synthesis.Such advancements are crucial for advancing more efficient and sustainable Fischer-Tropsch synthesis technologies,supporting the global push for net-zero emissions goals,and contributing to carbon reduction efforts worldwide. 展开更多
关键词 Fischer-Tropsch synthesis Syngas conversion Carbon dioxide Carbon efficiency Iron carbide Graphene layer confinement
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Size matters:quantum confinement-driven dynamics in CsPbI_(3)quantum dot light-emitting diodes 被引量:1
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作者 Shuo Li Wenxu Yin +1 位作者 Weitao Zheng Xiaoyu Zhang 《Journal of Semiconductors》 2025年第4期55-61,共7页
The quantum confinement effect fundamentally alters the optical and electronic properties of quantum dots(QDs),making them versatile building blocks for next-generation light-emitting diodes(LEDs).This study investiga... The quantum confinement effect fundamentally alters the optical and electronic properties of quantum dots(QDs),making them versatile building blocks for next-generation light-emitting diodes(LEDs).This study investigates how quantum confinement governs the charge transport,exciton dynamics,and emission efficiency in QD-LEDs,using CsPbI_(3) QDs as a model system.By systematically varying QD sizes,we reveal size-dependent trade-offs in LED performance,such as enhanced efficiency for smaller QDs but increased brightness and stability for larger QDs under high current densities.Our findings offer critical insights into the design of high-performance QD-LEDs,paving the way for scalable and energy-efficient optoelectronic devices. 展开更多
关键词 quantum confinement effect CsPbI_(3) quantum dot light-emitting diode
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Absorption frequency band switchable intelligent electromagnetic wave absorbing carbon composite by cobalt confined catalysis 被引量:1
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作者 Luo Kong Haodong Cui +3 位作者 Shuyu Zhang Guiqin Zhang Jun Yang Xiaomeng Fan 《Journal of Materials Science & Technology》 2025年第8期203-211,共9页
The dielectric loss of carbon materials is closely related to the microstructure and the degree of crystallization,and the microstructure modulation of electromagnetic wave absorbing carbon materials is the key to enh... The dielectric loss of carbon materials is closely related to the microstructure and the degree of crystallization,and the microstructure modulation of electromagnetic wave absorbing carbon materials is the key to enhancing absorption properties.In this work,a porous elastic Co@CNF-PDMS composite was prepared by freeze-drying and confined catalysis.The graphitization degree and conductivity loss of carbon nanofibers(CNFs)were regulated by heat treatment temperature and Co catalyst content.The construction of a heterointerface between Co and C enhances the interfacial polarization loss.The Co@CNF-PDMS composite with 4.5 mm achieves the minimum reflection loss(RLmin)of-81.0 dB at 9.9 GHz and RL no higher than-12.1 dB in the whole of the X-band.After applying a load of up to 40% strain and 100 cycles to Co@CNF-PDMS,the dielectric properties of the composite remain stable.With the increase of compression strain,the distribution density of the absorbent increases,and the CNF sheet layer extrusion contact forms a conductive path,which leads to the conductive loss increase,finally,the absorption band moves to a high frequency.The absorption band can be bi-directionally regulated by loading and strain with good stability,which provides a new strategy for the development of intelligent electromagnetic wave absorbing materials. 展开更多
关键词 Carbon nanofiber Confined catalysis Electromagnetic wave absorbing material
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Photothermal effects of multidimensional confined MMC/TMs-MDCS catalyst for ultra-high photocatalytic hydrogen evolution 被引量:1
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作者 Huihua Luo Haifeng Zhu +4 位作者 Kehui Xue Chong Liu Nannan Chen Yaping Zhang Lianqing Yu 《Journal of Energy Chemistry》 2025年第5期655-669,共15页
Multidimensional confined structure systems are proposed and demonstrated by using MoO_(2)@MO_(2)C(MMC)to enhance the photothermal catalytic performance of the metal sulfides-multidimensional confined structure(TMs-MD... Multidimensional confined structure systems are proposed and demonstrated by using MoO_(2)@MO_(2)C(MMC)to enhance the photothermal catalytic performance of the metal sulfides-multidimensional confined structure(TMs-MDCS).Specifically,the MMC nanoparticles confined to the surface of the ZnIn_(2)S_(4)hollow tube-shell(MMC/HT-ZIS)achieve a hydrogen evolution rate of 9.72 mmol g^(-1)h^(-1),which is 11.2 times higher than that of pure HT-ZIS.Meanwhile,the MnCdS(MCS)nanoparticles are encapsulated within the two-dimensional MMC(2D MMC/MCS)through precise regulation of size and morphology.The 10-MMC/MCS lamellar network demonstrates the highest hydrogen evolution rate of 8.19 mmol g^(-1)-h^(-1).The obtained MMC/TMs-MDCS catalysts exhibit an enhanced photocatalytic hydrogen evolution rate,which can be attributed to the strong synergistic interaction between the multidimensional confinement and the photothermal effects.The confinement space and the strong interfacial relationship within the MMC/TMs-MDCS create abundant channels and active sites that facilitate electron migration and transport.Furthermore,the construction of a confined environment positions these materials as promising candidates for achieving exceptional photothermal catalytic performance,as MMC/TMs-MDCS enhance light absorption through light scattering and reflecting effects.Additionally,the capacity of MMC/TMsMDCS to convert solar light into thermal energy significantly reduces the activation energy of the reaction,thereby facilitating reaction kinetics and accelerating the separation and transport of photogenerated carriers.This work provides valuable insights for the development of highly efficient photothermal catalytic water-splitting systems for hydrogen production using multidimensional confined catalysts. 展开更多
关键词 Multidimensional confined effect Photothermal effect Photothermal catalytic hydrogen production
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Infrared spectroscopic analysis of O-H bond dynamics in one-dimensional confined water and bulk water
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作者 ZHANG Lei WANG Tian-Qi FAN Yan-Ping 《红外与毫米波学报》 北大核心 2025年第1期78-85,共8页
In sub nanometer carbon nanotubes,water exhibits unique dynamic characteristics,and in the high-frequency region of the infrared spectrum,where the stretching vibrations of the internal oxygen-hydrogen(O-H)bonds are c... In sub nanometer carbon nanotubes,water exhibits unique dynamic characteristics,and in the high-frequency region of the infrared spectrum,where the stretching vibrations of the internal oxygen-hydrogen(O-H)bonds are closely related to the hydrogen bonds(H-bonds)network between water molecules.Therefore,it is crucial to analyze the relationship between these two aspects.In this paper,the infrared spectrum and motion characteristics of the stretching vibrations of the O-H bonds in one-dimensional confined water(1DCW)and bulk water(BW)in(6,6)single-walled carbon nanotubes(SWNT)are studied by molecular dynamics simulations.The results show that the stretching vibrations of the two O-H bonds in 1DCW exhibit different frequencies in the infrared spectrum,while the O-H bonds in BW display two identical main frequency peaks.Further analysis using the spring oscillator model reveals that the difference in the stretching amplitude of the O-H bonds is the main factor causing the change in vibration frequency,where an increase in stretching amplitude leads to a decrease in spring stiffness and,consequently,a lower vibration frequency.A more in-depth study found that the interaction of H-bonds between water molecules is the fundamental cause of the increased stretching amplitude and decreased vibration frequency of the O-H bonds.Finally,by analyzing the motion trajectory of the H atoms,the dynamic differences between 1DCW and BW are clearly revealed.These findings provide a new perspective for understanding the behavior of water molecules at the nanoscale and are of significant importance in advancing the development of infrared spectroscopy detection technology. 展开更多
关键词 one-dimensional confined water infrared spectroscopy hydrogen bonds
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Hot-electron generation in high-intensity laser-matter experiments with copper targets
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作者 O.Renner O.Klimo +4 位作者 M.Krus Ph.Nicolaï A.Poletaeva N.Bukharskii V.T.Tikhonchuk 《Matter and Radiation at Extremes》 2025年第3期75-88,共14页
We investigate the spatial and temporal correlations of hot-electron generation in high-intensity laser interaction with massive and thin copper targets under conditions relevant to inertial confinement fusion.Using K... We investigate the spatial and temporal correlations of hot-electron generation in high-intensity laser interaction with massive and thin copper targets under conditions relevant to inertial confinement fusion.Using Ka time-resolved imaging,it is found that in the case of massive targets,the hot-electron generation follows the laser pulse intensity with a short delay needed for favorable plasma formation.Conversely,a significant delay in the x-ray emission compared with the laser pulse intensity profile is observed in the case of thin targets.Theoretical analysis and numerical simulations suggest that this is related to radiation preheating of the foil and the increase in hot-electron lifetime in a hot expanding plasma. 展开更多
关键词 laser matter interaction massive targetsthe inertial confinement fusion massive targets massive thin copper targets inertial confinement fusionusing hot electrons k time resolved imaging
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Introducing a new geostatistical approach to classify groundwater samples based on Stiff diagram: Case study of Chahardoly aquifer, west of Iran
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作者 Sajjad Moradi Nazarpoor Mohsen Rezaei +2 位作者 Hadi Jafari Yazdan Mohebi Reza Mirbageri 《Journal of Groundwater Science and Engineering》 2025年第4期423-433,共11页
Groundwater quality is pivotal for sustainable resource management,necessitating comprehen-sive investigation to safeguard this critical resource.This study introduces a novel methodology that inte-grates stiff diagra... Groundwater quality is pivotal for sustainable resource management,necessitating comprehen-sive investigation to safeguard this critical resource.This study introduces a novel methodology that inte-grates stiff diagrams,geostatistical analysis,and geometric computation to delineate the extent of a confined aquifer within the Chahrdoly aquifer,located west of Hamadan,Iran.For the first time,this approach combines these tools to map the boundaries of a confined aquifer based on hydrochemical characteristics.Stiff diagrams were used to calculate geometric parameters from groundwater chemistry data,followed by simulation using a linear model incorporating the semivariogram parameterγ(h).The Root Mean Square Error(RMSE)of the linear model was used to differentiate confined from unconfined aquifers based on hydrochemical signatures.Validation was conducted by generating a cross-sectional hydrogeological layer from well logs,confirming the presence of aquitard layers.The results successufully delineated the confined aquifer's extent,showing strong agreement with hydrogeological log data.By integrating stiff diagrams with semivariogram analysis,this study enhances the understanding of hydrochemical processes,offering a robust framework for groundwater resource identification and management. 展开更多
关键词 GEOSTATISTICS Stiff diagram SEMIVARIOGRAM Confined aquifer Chahardoly Asadabad
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Hydrodynamic instability growth of the fuel-ablator interface induced by rippled rarefaction waves in inertial confinement fusion implosion experiments
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作者 Zheng Yan Zhu Chen +6 位作者 Jiwei Li Lifeng Wang Zhiyuan Li Chao Zhang Fengjun Ge Junfeng Wu Weiyan Zhang 《Matter and Radiation at Extremes》 2025年第5期84-93,共10页
Hydrodynamic instability growth at the deuterium-tritium(DT)fuel-ablator interface plays a critical role in determining the performance of inertial confinement fusion implosions.During the late stages of implosion,ins... Hydrodynamic instability growth at the deuterium-tritium(DT)fuel-ablator interface plays a critical role in determining the performance of inertial confinement fusion implosions.During the late stages of implosion,insufficient doping of the ablator material can result in highenergy X-ray preheat,which may trigger the development of a classical-like Rayleigh-Taylor instability(RTI)at the fuel-ablator interface.In implosion experiments at the Shenguang 100 kJ-level laser facility,the primary source of perturbation is the roughness of the inner DT ice interface.In this study,we propose an analytical model to describe the feed-out process of the initial roughness of the inner DT ice interface.The perturbation amplitude derived from this model serves as the initial seed for the late-time RTI during the acceleration phase.Our findings confirm the presence of classical-like RTI at the fuel-ablator interface.Numerical simulations conducted using a radiation hydrodynamic code validate the proposed analytical model and demonstrate the existence of a peak mode number in both the feed-out process and the classical-like RTI.It provides an alternative bridge between the current target fabrication limitations and the unexpected implosion performance. 展开更多
关键词 inertial confinement fusion fuel ablator interface Rayleigh Taylor instability hydrodynamic instability radiation hydrodynamic code numerical simulations rippled rarefaction waves performance inertial confinement fusion implosionsduring
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