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基于气象相似日修正和IPO-DLinear的日前电力负荷预测
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作者 于惠钧 赵文川 +3 位作者 刘颉 徐银凤 邹海 辜海缤 《电力工程技术》 北大核心 2026年第2期121-130,共10页
现有电力负荷预测方法面临诸多挑战,尤其是在考虑气象因素对负荷波动的影响时,传统方法往往忽视气象特征与负荷之间复杂的非线性关系,导致预测精度不足。对此文中提出一种基于气象相似日修正(meteorological similar day correction,MS... 现有电力负荷预测方法面临诸多挑战,尤其是在考虑气象因素对负荷波动的影响时,传统方法往往忽视气象特征与负荷之间复杂的非线性关系,导致预测精度不足。对此文中提出一种基于气象相似日修正(meteorological similar day correction,MSDC)和改进鹦鹉优化(improved parrot optimizer,IPO)线性分解(decomposition-based linear,DLinear)的日前电力负荷预测模型。首先运用Logistic映射、自适应变异策略、螺旋波动搜索IPO对DLinear超参数进行优化,然后由DLinear提取数据的周期性和趋势性特征,最后通过比对气象特征欧氏距离修正负荷预测值,形成基于IPO-DLinear-MSDC的日前电力负荷预测模型。采用2024年6月至10月湖南株洲地区总电力负荷数据集进行仿真分析,IPO-DLinear-MSDC模型的输出平均绝对百分比误差(mean absolute percentage error,MAPE)、决定系数R2分别为4.67%、0.833,相较于IPO-DLinear与PO-DLinear模型,MAPE分别下降了0.83个百分点、1.43个百分点,R2分别提升了0.074、0.125。 展开更多
关键词 日前电力负荷预测 气象相似日修正(MSDC) 改进鹦鹉优化(IPO) 线性分解(Dlinear) LOGISTIC映射 欧氏距离
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Phase Transformation on Chemically Corroded Surface of a Single-Crystal Superalloy During In-Situ Tension at Elevated Temperatures
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作者 Wang Rui Li Jiarong +2 位作者 Yue Xiaodai Zhao Jinqian Yang Wanpeng 《稀有金属材料与工程》 北大核心 2026年第3期595-601,共7页
In-situ tensile tests were conducted on a chemically corroded third-generation single-crystal superalloy DD9 at 980 and 1100℃.The phase transformation in the surface areas during the tensile process was analyzed usin... In-situ tensile tests were conducted on a chemically corroded third-generation single-crystal superalloy DD9 at 980 and 1100℃.The phase transformation in the surface areas during the tensile process was analyzed using field emission scanning electron microscope,energy dispersive X-ray spectroscope,electron probe X-ray microanalysis,and transmission electron microscope.The phase transformation mechanism on the surface and the influence mechanism were studied through observation and dynamic calculation.During tensile tests at elevated temperatures,chemical corrosion promotes the precipitation of topologically close-packed(tcp)μphase andσphase on the alloy surface.Both the precipitation amount and size of these two phases on the surface at 1100℃are greater than those at 980℃.The precipitation of tcp phase on the alloy surface results in the formation of an influence layer on the surface area,and the distribution characteristics of alloying elements are significantly different from those of the substrate.The depth of the influence layer at 1100℃is greater than that at 980℃.The precipitation of tcp phase prompts the phase transition fromγphase toγ′phase around the tcp phase. 展开更多
关键词 single-crystal superalloy in-situ tension tcp phase phase transformation alloying element
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Peak current reduction in presence of RF phase modulationin the dual RF system
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作者 Jiang Bocheng Zhang Yao Tsai Cheng-Ying 《强激光与粒子束》 北大核心 2026年第1期160-165,共6页
[Background]High harmonic cavities are widely used in electron storage rings to lengthen thebunch,lower the bunch peak current,thereby reducing the IBS effect,enhancing the Touschek lifetime,as well asproviding Landau... [Background]High harmonic cavities are widely used in electron storage rings to lengthen thebunch,lower the bunch peak current,thereby reducing the IBS effect,enhancing the Touschek lifetime,as well asproviding Landau damping,which is particularly important for storage rings operating with ultra-low emittance or atlow beam energy.[Purpose]To further increase the bunch length without additional hardware costs,the phasemodulation in a dual-RF system is considered.[Methods]In this paper,turn-by-turn simulations incorporating randomsynchrotron radiation excitation are conducted,and a brief analysis is presented to explain the bunch lengtheningmechanism.[Results]Simulation results reveal that the peak current can be further reduced,thereby mitigating IBSeffects and enhancing the Touschek lifetime.Although the energy spread increases,which tends to reduce thebrightness of higher-harmonic radiation from the undulator,the brightness of the fundamental harmonic can,in fact,beimproved. 展开更多
关键词 dual high-frequency system phase modulation beam bunch stretching intra-beam scattering
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Effect of Addition of Er-TiB_(2)Dual-Phase Nanoparticles on Strength-Ductility of Al-Mn-Mg-Sc-Zr Alloy Prepared by Laser Powder Bed Fusion
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作者 Li Suli Zhang Yanze +5 位作者 Yang Mengjia Zhang Longbo Xie Qidong Yang Laixia MaoFeng Chen Zhen 《稀有金属材料与工程》 北大核心 2026年第1期9-17,共9页
A dual-phase synergistic enhancement method was adopted to strengthen the Al-Mn-Mg-Sc-Zr alloy fabricated by laser powder bed fusion(LPBF)by leveraging the unique advantages of Er and TiB_(2).Spherical powders of 0.5w... A dual-phase synergistic enhancement method was adopted to strengthen the Al-Mn-Mg-Sc-Zr alloy fabricated by laser powder bed fusion(LPBF)by leveraging the unique advantages of Er and TiB_(2).Spherical powders of 0.5wt%Er-1wt%TiB_(2)/Al-Mn-Mg-Sc-Zr nanocomposite were prepared using vacuum homogenization technique,and the density of samples prepared through the LPBF process reached 99.8%.The strengthening and toughening mechanisms of Er-TiB_(2)were investigated.The results show that Al_(3)Er diffraction peaks are detected by X-ray diffraction analysis,and texture strength decreases according to electron backscatter diffraction results.The added Er and TiB_(2)nano-reinforcing phases act as heterogeneous nucleation sites during the LPBF forming process,hindering grain growth and effectively refining the grains.After incorporating the Er-TiB_(2)dual-phase nano-reinforcing phases,the tensile strength and elongation at break of the LPBF-deposited samples reach 550 MPa and 18.7%,which are 13.4%and 26.4%higher than those of the matrix material,respectively. 展开更多
关键词 Al-Mn-Mg-Sc-Zr alloy laser powder bed fusion nano-reinforcing phase synergistic enhancement
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CTA联合PHASES评分对颅内动脉瘤破裂出血预后的价值分析
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作者 张杰 鲁东 吕维富 《影像研究与医学应用》 2026年第2期17-21,共5页
目的:探讨头颈部CT血管造影(CTA)联合PHASES评分对颅内动脉瘤破裂导致动脉瘤性蛛网膜下腔出血(aSAH)预后的价值。方法:回顾性分析2022年1月—2024年10月在亳州市中医院接受诊疗的67例aSAH患者病例资料。根据格拉斯哥预后评分,将患者分... 目的:探讨头颈部CT血管造影(CTA)联合PHASES评分对颅内动脉瘤破裂导致动脉瘤性蛛网膜下腔出血(aSAH)预后的价值。方法:回顾性分析2022年1月—2024年10月在亳州市中医院接受诊疗的67例aSAH患者病例资料。根据格拉斯哥预后评分,将患者分为预后良好组(n=37)和预后不良组(n=30)。采用单因素及多因素Logistic回归分析比较组间临床、影像及PHASES评分,筛选aSAH患者预后的独立预测因素并构建回归模型。绘制受试者工作特征(ROC)曲线,评估各单一独立预测因素及回归模型预测aSAH患者预后的效能。结果:预后不良组患者Hunt-Hess分级Ⅳ~Ⅴ级的占比、AR值、SR值、入射夹角和PHASES评分均高于预后良好组,发病至治疗时间>3 d的占比高于预后良好组,差异有统计学意义(P<0.05)。多因素Logistic回归分析结果显示,Hunt-Hess分级、入射夹角和PHASES评分为aSAH患者不良结局的影响因素(P<0.05),其曲线下面积(AUC)分别为0.613、0.658、0.761;以三者联合构建的回归模型预测患者预后的诊断灵敏度为0.733,特异度为0.919,AUC为0.898。结论:CTA联合PHASES评分能够有效提升对aSAH患者预后的预测效能,有助于临床进行预后判断。 展开更多
关键词 颅内动脉瘤 破裂出血 CT血管造影 phaseS评分 预后价值
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Skin-Inspired Ultra-Linear Flexible Iontronic Pressure Sensors for Wearable Musculoskeletal Monitoring
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作者 Pei Li Shipan Lang +6 位作者 Lei Xie Yong Zhang Xin Gou Chao Zhang Chenhui Dong Chunbao Li Jun Yang 《Nano-Micro Letters》 2026年第2期454-470,共17页
The growing prevalence of exercise-induced tibial stress fractures demands wearable sensors capable of monitoring dynamic musculoskeletal loads with medical-grade precision.While flexible pressure-sensing insoles show... The growing prevalence of exercise-induced tibial stress fractures demands wearable sensors capable of monitoring dynamic musculoskeletal loads with medical-grade precision.While flexible pressure-sensing insoles show clinical potential,their development has been hindered by the intrinsic trade-off between high sensitivity and full-range linearity(R^(2)>0.99 up to 1 MPa)in conventional designs.Inspired by the tactile sensing mechanism of human skin,where dermal stratification enables wide-range pressure adaptation and ion-channelregulated signaling maintains linear electrical responses,we developed a dual-mechanism flexible iontronic pressure sensor(FIPS).This innovative design synergistically combines two bioinspired components:interdigitated fabric microstructures enabling pressure-proportional contact area expansion(αP1/3)and iontronic film facilitating self-adaptive ion concentration modulation(αP^(2/3)),which together generate a linear capacitance-pressure response(CαP).The FIPS achieves breakthrough performance:242 kPa^(-1)sensitivity with 0.997linearity across 0-1 MPa,yielding a record linear sensing factor(LSF=242,000).The design is validated across various substrates and ionic materials,demonstrating its versatility.Finally,the FIPS-driven design enables a smart insole demonstrating 1.8%error in tibial load assessment during gait analysis,outperforming nonlinear counterparts(6.5%error)in early fracture-risk prediction.The biomimetic design framework establishes a universal approach for developing high-performance linear sensors,establishing generalized principles for medical-grade wearable devices. 展开更多
关键词 Iontronic sensor Skin-inspired design linear range linear sensing factor Biomechanical monitoring
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Global Optimization Algorithm for Minimizing Linear Fractional Programming
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作者 ZHAO Peng SHEN Pei-ping ZHONG Zhe-wei 《Chinese Quarterly Journal of Mathematics》 2026年第1期50-59,共10页
In this paper,we study a class of Linear Fractional Programming on a nonempty bounded set,called the Problem(LFP),and design a branch and bound algorithm to find the global optimal solution of the problem(LFP).First,w... In this paper,we study a class of Linear Fractional Programming on a nonempty bounded set,called the Problem(LFP),and design a branch and bound algorithm to find the global optimal solution of the problem(LFP).First,we convert the problem(LFP)to the equivalent problem(EP2).Secondly,by applying the linear relaxation technique to the problem(EP2),the linear relaxation programming problem(LRP2Y)was obtained.Then,the overall framework of the algorithm is given,and the convergence and complexity of the algorithm are analyzed.Finally,experimental results are listed to illustrate the effectiveness of the algorithm. 展开更多
关键词 Global optimization linear Fractional Programming Branch and bound algorithm linear relaxation
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Co-optimization of linear gain and dynamic range for atomic superheterodyne receivers based on homodyne readout
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作者 Chuan Qu Dongqin Guo Jian Zhang 《Chinese Physics B》 2026年第1期416-423,共8页
Rydberg-atom-based superheterodyne receivers integrate self-calibration,high sensitivity,a wide operational frequency range,and phase/frequency resolved detection capabilities,demonstrating broad application prospects... Rydberg-atom-based superheterodyne receivers integrate self-calibration,high sensitivity,a wide operational frequency range,and phase/frequency resolved detection capabilities,demonstrating broad application prospects as nextgeneration microwave receivers.Linear gain and linear dynamic range(LDR)are critical metrics for assessing receiver sensitivity and demodulation fidelity,respectively.We numerically solve the four-level master equation and then employ particle swarm optimization(PSO)algorithm to co-optimize linear gain and LDR in atomic superheterodyne receivers based on balanced homodyne detection.Further,we systematically account for dominant dephasing mechanisms in the simulation,encompassing spontaneous decay,transit dephasing,collision dephasing,laser linewidth dephasing,and Doppler averaging.Homodyne readout utilizes both the real and imaginary parts of polarizability for sensing.In the case of the photon shot noise limit,its signal-to-noise ratio(SNR)expression resembles that of direct optical-intensity readout.However,the inherent coherent subtraction operation in homodyne detection significantly suppresses common-mode noise,while appropriately increasing the reference beam power enhances the gain in practical experiments.Indeed,this co-optimization problem,characterized by a high-dimensional variable space,two objectives,and non-convexity,is well-suited for solution by PSO.In addition,probe and coupling detuning contribute equivalently to polarizability and compensate for each other owing to Doppler averaging,thereby reducing the optimization variable space by one.By adopting a product form of linear gain and LDR as the fitness function,the PSO achieves rapid convergence.Here,the effectiveness of the PSO results is verified via the total harmonic distortion(THD).The relative error-based LDR calculation method we proposed efficiently measures receiver response linearity with consuming fewer computational resources.This research is expected to offer valuable insights into enhancing the performance of Rydberg-atom-based superheterodyne receivers. 展开更多
关键词 atomic superheterodyne receivers linear gain linear dynamic range balanced homodyne readout
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Design of electrocaloric materials based on E–T phase diagrams
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作者 Fei Han Rongju Zhong +2 位作者 Jikun Yang Chuanbao Liu Yang Bai 《Chinese Physics B》 2026年第2期71-83,共13页
As electronic technology continues to evolve towards miniaturization and integration,the demand for micro-refrigeration technology in microelectronic systems is increasing.Ferroelectric(FE)refrigeration technology bas... As electronic technology continues to evolve towards miniaturization and integration,the demand for micro-refrigeration technology in microelectronic systems is increasing.Ferroelectric(FE)refrigeration technology based on the electrocaloric effect(ECE)has emerged as a highly promising candidate in this field,due to its advantages of high energy efficiency,simple structure,easy miniaturization,low cost,and environmental friendliness.The EC performance of FE materials essentially depends on the phase transition features under the coupled electric and thermal fields,making the E–T phase diagram a core tool for decoding the underlying mechanism of ECE.This paper reviews the development of EC materials,focusing on the comprehensive study of E–T phase diagrams.By correlating the microscopic phase structure of FE materials with the macroscopic physical properties,it clarifies the manipulation mechanism for enhanced ECE performance,providing theoretical support for the targeted design of high-performance EC materials.In the future,the introduction of data-driven methods is expected to enable the high-throughput construction of FE phase diagrams,thereby accelerating the optimization of high-performance EC materials and promoting the practical application of FE refrigeration technology. 展开更多
关键词 ferroelectric material electrocaloric effect phase diagram phase transition sold-state refrigeration
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Recent advances in the properties,synthesis,and applications of oriented composite phase change materials
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作者 Jun Tong Zui Tao +5 位作者 Wenjie Hou Chaoxing Yang Tiantian Yuan Huimin Liao Xiubing Huang Ge Wang 《Journal of Energy Chemistry》 2026年第1期902-944,I0020,共44页
In the context of the global energy low-carbon transition,phase change energy storage technology becomes a key technology to solve the problem of intermittent renewable energy.Oriented phase change composites(OCPCMs)r... In the context of the global energy low-carbon transition,phase change energy storage technology becomes a key technology to solve the problem of intermittent renewable energy.Oriented phase change composites(OCPCMs)receive widespread attention in practical energy storage applications due to their unique oriented thermally conductive structure,which achieves significant thermal conductivity enhancement in specific directions while retaining the high energy storage capacity of the phase change components.This review systematically summarizes the overall analysis of OCPCMs from synthesis and preparation to application scenarios in recent years.Herein,we introduce the analysis of the heat transfer mechanism of the materials and explore the advantages of the oriented structure in OCPCMs in the heat transfer behavior from a bionic perspective.We then focus on summarizing and generalizing the methods for preparing OCPCMs,giving suggestions for suitable methods according to different scenarios.Besides,we discuss the application of finite element simulation methods to the monitoring of the thermal management behavior of OCPCMs,and look into the potential future application areas of such materials.Finally,it is hoped that this review will provide guidance for the academic community in developing high-performance OCPCMs. 展开更多
关键词 phase change materials Oriented phase change composites Oriented thermal conduction Thermal conductivity enhancements
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Microstructure tailoring and enhanced fracture toughness in as-extruded Mg-9Gd-4Y-1Zn-0.5Zr alloy via lamellarγ’phase
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作者 Zhikang Ji Wanting Sun +6 位作者 Xiaoguang Qiao Lin Yuan Fuguan Cong Guojun Wang Zhuoran Zeng Mingyi Zheng Shiwei Xu 《Journal of Magnesium and Alloys》 2026年第1期396-409,共14页
In this study,by adjusting the homogenization process,numerous lamellar-shapedγ’phases are generated and uniformly distributed throughout the grain interior within as-extruded Mg-9Gd-4Y-1Zn-0.5Zr(wt.%)alloy,leading ... In this study,by adjusting the homogenization process,numerous lamellar-shapedγ’phases are generated and uniformly distributed throughout the grain interior within as-extruded Mg-9Gd-4Y-1Zn-0.5Zr(wt.%)alloy,leading to a remarkable increase enhancement in both tensile strength and fracture toughness.Notably,as compared to the alloy containing block-shaped long-period stacking-ordered(LPSO)phase,when the lamellar-shapedγ’phase is introduced within theα-Mg matrix,the fracture toughness of 29.7 MPa·m^(1/2)can be achieved with a 27%improvement.This superior fracture resistance is mainly attributed to the delamination toughening derived from the intensive micro-cracks occurring alongγ’phase interfaces oriented perpendicular to the primary fracture surface.Owing to the presence of lamellarshapedγ’phase,the fracture morphology can be significantly changed and characterized with deep dimples and pronounced deflection of main crack,which collectively contribute to the enhanced plastic energy dissipation and fracture toughness.The characteristics of deformed microstructure near the fracture surface demonstrate the activation of kinking and the inhibition of twin propagation due to the interactions with lamellarγ’phase.Such deformation behavior can effectively impede the crack propagation and contribute to the superior fracture resistance.Besides,the X-ray computed tomography analysis of the fractured alloy exhibits the distribution and size of voids,indicating that the prolate voids preferentially nucleate and propagate parallel to the lamellarγ’phase.Accordingly,the deformation mechanisms under a triaxial stress state involve the intricate interplay between lamellarγ’phase-induced delamination,crack deflection as well as void formation.Through the application of tailored pre-treatment heat treatment processes,the control of phase constituents within the microstructure can be achieved to improve the mechanical properties of Mg alloys.It is anticipated to provide a comprehensive understanding of the fracture behavior of Mg-Gd-Y-Zn-Zr,with particular emphasis on the synergistic effects of lamellarγ’phase and LPSO phase in the optimization of overall mechanical performance. 展开更多
关键词 Mg-Gd-Y-Zn-Zr alloy Long period stacking ordered phase γ’phase Fracture toughness Toughening mechanism
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Illusion Optics via Phase-Gradient Metasurfaces
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作者 Zhaoyao Pan Jinpeng Yang Yadong Xu 《Chinese Physics Letters》 2026年第1期31-36,共6页
Optical phase-gradient metasurfaces have garnered significant attention for enabling flexible light manipulation,with applications across diverse domains.In this work,we will demonstrate that the metasurfaces with pha... Optical phase-gradient metasurfaces have garnered significant attention for enabling flexible light manipulation,with applications across diverse domains.In this work,we will demonstrate that the metasurfaces with phase gradient modulation can be used to achieve illusion optics,featuring the advantages of simple geometric structure and feasible implementation compared with the well-known transformation optics method.The underlying mechanism is the anomalous diffraction law caused by the phase gradient,which provides a theoretical basis for freely manipulating the propagation path of light.By considering a specific example,we will demonstrate that the phase gradient can transform spatial coordinates in real space into illusion space,thereby converting a plane in real space into a curved surface structure in illusion space to achieve the illusion effect.This approach provides a viable alternative to transformation optics for designing illusion devices. 展开更多
关键词 transformation optics anomalous diffraction law illusion opticsfeaturing flexible light manipulationwith illusion optics anomalous diffraction phase gradient modulation phase gradient metasurfaces
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Thermodynamic insights and equilibrium phase diagrams of carbon deposition and carburization on iron surfaces in C-H-O system
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作者 Zeng Liang Ke-Jiang Li +6 位作者 Zong-Hao Yang Qing-Song Zou Chun-He Jiang Shan Ren Jian-Liang Zhang Alberto N.Conejo Marco Aurelio Ramirez Argaez 《Journal of Iron and Steel Research International》 2026年第1期53-65,共13页
The direct reduction process can reduce carbon emissions by over 50%compared to traditional blast furnace ironmaking.Carbon deposition and carburization are critical for ensuring process stability and economic viabili... The direct reduction process can reduce carbon emissions by over 50%compared to traditional blast furnace ironmaking.Carbon deposition and carburization are critical for ensuring process stability and economic viability.Thermodynamic phase diagrams were developed to intuitively represent carbon deposition and carburization preferences in CH4-CO-H_(2) ternary atmospheres.High carbon potential and low oxygen potential significantly enhance carbon deposition and carburization.Increasing temperature from 500 to 1000℃ shifts the dominant reactions from CO-based to CH_(4)-based,increasing maximum carbon deposition from 0.55 to 0.80 mol and carburization from 0.25 to 0.80 mol per mole of reducing gas.Increasing pressure suppresses CH4-based reactions while promoting CO-based reactions,reducing maximum carbon deposition from 0.8 to~0.7 mol and increasing maximum carburization from 0.80 to 0.85 mol per mole of reducing gas.Equilibrium phase diagrams for various carbides were also developed,revealing preferences for Fe_(3)C_(2),Fe_(7)C_(3),Fe_(5)C_(2),and Fe_(3)C as the Fe/C ratio increases.Higher temperatures and CH_(4) concentrations favor the formation of carbides with higher carbon content.Carburization preferences under typical Energiron ZR and Midrex atmospheres were highlighted,and the higher carbon content in direct reduction iron produced by the Energiron ZR process was thermodynamically confirmed. 展开更多
关键词 Carbon deposition CARBURIZATION THERMODYNAMICS phase diagram C-H-O system
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Linear relationship between reactivity and the reciprocal of uranium concentration in thermal‑spectrum molten salt reactors
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作者 Chang-Qing Yu Gui-Feng Zhu +7 位作者 Shu-Yang Jia Yang Zou Rui Yan Jian Guo Ya-Fen Liu Bo Zhou Xue-Chao Zhao Xiao-Han Yu 《Nuclear Science and Techniques》 2026年第2期208-222,共15页
Knowing the precise relationship between fuel loading and reactivity is essential for guiding reactor criticality extrapolation and online refueling in molten salt reactors(MSRs).This study aims to explore and explain... Knowing the precise relationship between fuel loading and reactivity is essential for guiding reactor criticality extrapolation and online refueling in molten salt reactors(MSRs).This study aims to explore and explain the linear relationship between reactivity and the reciprocal of uranium concentration in thermal-spectrum MSRs.By applying neutron balance theory,we analyzed the neutron absorption cross sections of various nuclides in single-lattice models with varying fuel concentrations.Our findings reveal a simple linear correlation between reactivity and the reciprocal of uranium concentration,which can be explained from the perspective of nuclear reaction cross sections that adhere to the 1/v law in the thermal neutron spectrum.Furthermore,we identified that the neutron absorption single-group cross sections of structural materials and carrier salts exhibit an approximately linear relationship with the fission single-group cross section of ^(235) U;similarly,the reciprocal of ^(235)U’s fission cross section exhibits an approximately linear relationship with uranium concentration.This linear relationship deviates as the volume fraction of molten salt increases,due to a greater proportion of neutrons being captured in the resonance energy spectrum.However,it remains valid for molten salt volume fractions up to 25%and demonstrates broad applicability in the physical design and operation of thermal molten salt reactors. 展开更多
关键词 Molten salt reactor REACTIVITY Uranium concentration Cross sections linear
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Review of heterogeneous nucleation to microstructure refinement in steel induced by second phase
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作者 Zi-Yi Ge Chuang Feng +4 位作者 Yong-Kun Yang Ji Zhou Guo-Xing Qiu Xiao-Ming Li Dong-Ping Zhan 《Journal of Iron and Steel Research International》 2026年第1期311-328,共18页
Heterogeneous nucleation,characterized by its low nucleation barrier and controllable nucleation sites,has been widely employed to manipulate the microstructures and properties of metallic materials.In recent years,th... Heterogeneous nucleation,characterized by its low nucleation barrier and controllable nucleation sites,has been widely employed to manipulate the microstructures and properties of metallic materials.In recent years,the dispersion of inclusions,carbides,and microstructure refinement in steel have emerged as one of the key research directions in the development of high-quality steel.The current research status regarding the regulation of inclusions,carbides,and microstructures in steel through heterogeneous nucleation are reviewed.The key points and challenges in refining the second phase and microstructure in steel using inclusion particles are highlighted,aiming to provide inspiration and references for future scholars.Deoxidized inclusions,when refined and dispersed,exhibit favorable lattice matching with second phases(e.g.,nitrides,sulfides,carbides)in steel.This characteristic serves as the fundamental mechanism for achieving refinement of the second phase.Concurrently,the solid-solution alloying effect from deoxidizing metals contributes to second-phase refinement,an aspect that requires prioritized investigation.In addition to the single heterogeneous nucleation refinement effect,the two-stage heterogeneous nucleation refinement of the second phase and microstructure offers a new approach for follow-up research.Notably,second-phase particles added as heterogeneous nucleation sites via external addition often require surface modification to ensure their stable retention in steel at high temperatures,which remains a major challenge restricting the widespread application of this method.Currently,the explanation of heterogeneous nucleation phenomena primarily relies on empirical calculations of lattice mismatch between the substrate and the nucleating phase,which cannot fully elucidate the quantitative relationship on the interface between the substrate and the nucleation phase.On this basis,quantifying the electronic structure and nucleation barrier at the interface between the substrate and the nucleation phase is a critical direction worthy of increased attention in the future. 展开更多
关键词 Heterogeneous nucleation Inclusion metallurgy INTERFACE Second phase MICROSTRUCTURE
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InSAR monitoring of large gradient deformation in coalfield and phase unwrapping research
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作者 Zihan Liu Junhuan Peng +3 位作者 Huiwei Su Xiang Li Chenyu Wang Yun Peng 《Geodesy and Geodynamics》 2026年第1期130-144,共15页
Small Baseline Subset Interferometric Synthetic Aperture Radar(SBAS-In SAR)is widely used for deformation monitoring in mining regions.However,phase unwrapping errors often limit its effectiveness in areas with large-... Small Baseline Subset Interferometric Synthetic Aperture Radar(SBAS-In SAR)is widely used for deformation monitoring in mining regions.However,phase unwrapping errors often limit its effectiveness in areas with large-gradient displacements.We propose a novel approach integrating spatiotemporal modeling to address this limitation and improve phase unwrapping.The Simplified Rectangular Dislocation Model(SRDM)simplifies the phase recovery process by reducing model parameters and improving efficiency in large-gradient deformation zones.Subsequently,the Power Exponential Knothe Model(PEKM)is applied to invert the deformation time series and restore the deformation phase from the time dimension.We validated this method using Sentinel-1 and Radarsat-2 data in the Majialiang Coalfield,China.The results demonstrate that the approach achieved 5%(Sentinel-1)and 14%(Radarsat-2)phase range extensions,elevating maximum detectable phase values from 120/100 rad to 160 rad for respective datasets,while the proportions of pixel points with restored phase exceeding 8 rad(-0.035 m)were 17.4%and 32.1%.The proposed method outperformed conventional techniques in resolving phase discontinuities,demonstrating strong adaptability.This approach significantly enhances subsidence monitoring accuracy and supports sustainable mining operations in coal-dependent regions. 展开更多
关键词 Mine subsidence SBAS-InSAR phase unwrapping Subsidence model
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Volume change and creep behaviors related to stress-phase transition path in methane hydrate-bearing silty sand
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作者 Jiazuo Zhou Qi Fan +1 位作者 Zhenyu Zhu Changfu Wei 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1526-1540,共15页
The volume change behavior of natural gas hydrate-bearing sediment is essential as it influences settlement,strength,and stiffness,which directly affect the stability of hydrate reservoirs during hydrate extraction or... The volume change behavior of natural gas hydrate-bearing sediment is essential as it influences settlement,strength,and stiffness,which directly affect the stability of hydrate reservoirs during hydrate extraction or in response to environmental changes.The volume change is influenced not only by stress but also by the formation and dissociation of hydrates.This study adopted a customized apparatus for one-dimensional compression tests,allowing independent control of gas pressure and effective stress.Tests were conducted on samples with different hydrate saturations along various temperature-gas pressure-effective stress paths,yielding some conclusions related to compressibility and creep.An unusual phenomenon was observed under low-stress conditions:hydrate formation led to shrinkage rather than expansion.Three potential mechanisms behind this occurrence were discussed.As hydrate saturation increases,the yield stress rises while the compression and swelling indexes remain minimally affected.After hydrate dissociation,the compression curve of hydrate-bearing sediment drops to that of hydrate-free sediment.Once hydrate is formed,the compression curve of hydrate-free sediment gradually approaches that of hydrate-bearing sediment during the subsequent loading.Under low-stress conditions,the creep of both hydrate-free and hydrate-bearing sediments is very weak.However,when stress increases,significantly beyond the yield stress,the creep of both sediments increases significantly,with hydrate-bearing sediment exhibiting much greater creep than hydrate-free sediment. 展开更多
关键词 Hydrate-bearing sediment phase transition Volume change Creep behavior
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Phase geometric propagation model of spherical projectile impacting thin plate based on shock wave propagation
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作者 Lvtan Chen Qiguang He +3 位作者 Chenyang Wu Ying Chen Qunyi Tang Xiaowei Chen 《Defence Technology(防务技术)》 2026年第2期14-31,共18页
Material phase-transition represents a significant phenomenon and mechanism in the context of hypervelocity protection.This study presents a thorough analysis of the phase-transition phenomena induced by shock pressur... Material phase-transition represents a significant phenomenon and mechanism in the context of hypervelocity protection.This study presents a thorough analysis of the phase-transition phenomena induced by shock pressure as the shock wave propagates initially to the rear of the projectile.The shock wave that induces a phase-transition is commonly referred to as a macroscopic phase-transition wave,whereas the interface that separates the distinct phases is referred to as macroscopic phase-boundary.The contact interface between the spherical projectile and the thin plate,characterized by its curved surface,plays a significant role in the nonlinear propagation and evolution of wave systems.The pressure distribution along the central axis of a spherical projectile is derived in accordance with the linear decay law observed for axial pressure.On this basis,a quadratic function is employed to characterize the trend of changes in wave front pressure,thereby facilitating the establishment of a model for wave front pressure distribution.Using the phase-transition pressure criterion for materials,the wave front phase evolution process is derived,and the macroscopic phase-boundary is determined.Based on the geometric propagation model(GPM)and the pressure distribution of the wave front,a phase geometric propagation model(PGPM)is proposed.The phase distribution of a spherical projectile impacting a thin plate is obtained by theoretical methods.The accuracy of the PGPM is subsequently validated through a comparison of its results with those obtained from numerical simulations. 展开更多
关键词 Hypervelocity impact Debris cloud phase-TRANSITION Pressure distribution phase distribution
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Integrating optical and radiofrequency interferometry for enhanced phase sensing
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作者 Ruimin Jie Zhaopeng Zhang +1 位作者 Chen Zhu Jie Huang 《Advanced Photonics Nexus》 2026年第1期111-121,共11页
Interferometry is a crucial investigative technique used across diverse fields to achieve highprecision measurements.It works by analyzing the phase difference between two interfering waves,which results from variatio... Interferometry is a crucial investigative technique used across diverse fields to achieve highprecision measurements.It works by analyzing the phase difference between two interfering waves,which results from variations in optical path lengths within an interferometer.We introduce a novel method for directly measuring changes in the phase difference within an optical interferometer,importantly,with the added advantage of a controllable enhancement factor.This approach is achieved through a two-step process:first,the optical phase difference is encoded into a sub-GHz radiofrequency(RF)signal using microwave-photonic manipulation;then,RF interferometry-assisted phase amplification is implemented at the destructive interference point.In our experiments,we demonstrate a phase sensitivity of 2.14 rad∕nm operating at 140 MHz using a miniature in-fiber Fabry-Pérot interferometer for sub-nanometer displacement sensing,which reveals a sensitivity magnification factor of 258.6.With further refinement,we anticipate that even higher enhancement factors can be achieved,paving the way for the development of cost-effective,ultrasensitive interferometry-based instruments for high-precision optical measurements. 展开更多
关键词 fiber-optic interferometer microwave photonics INTERFEROMETRY phase sensing radiofrequency interferometry
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Ultra-broadband acoustic logic gate based on passive phase manipulation
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作者 Yu-Han Xia Nai-Qi Pang +2 位作者 Yin Wang Long-Xu Wang Yong Ge 《Chinese Physics B》 2026年第1期514-520,共7页
In recent years,acoustic logic gates has attracted growing interest in acoustics due to their promising applications in acoustic communication and signal processing.For practical implementation,these logic gates must ... In recent years,acoustic logic gates has attracted growing interest in acoustics due to their promising applications in acoustic communication and signal processing.For practical implementation,these logic gates must operate over a certain bandwidth to ensure reliable performance.However,current experimental realizations have predominantly been confined to single-frequency or narrowband operation,leaving their broadband capabilities largely unverified.To address this gap,we present both numerical and experimental demonstrations of three basic acoustic logic gates(OR,NOT,and AND)using a phased unit cell composed of a central channel flanked by two arrays of semicircular cavities.By leveraging phase modulation of the unit cells and linear interference of sound,we achieve these logic operations with a uniform threshold of I_(t)=0.25.Remarkably,the measured fractional bandwidths(bandwidth relative to center frequency)reach approximately 111.5%(OR),37.2%(NOT),and 48.5%(AND),demonstrating ultra-broadband functionality.The proposed logic gates combine exceptional bandwidth with structural simplicity,offering significant potential for applications in acoustic computing,information processing,and integrated acoustic systems. 展开更多
关键词 acoustic logic gate ultra-broad band phased unit cell
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