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Quasi-visualizable detection of deep sub-wavelength defects in patterned wafers by breaking the optical form birefringence 被引量:1
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作者 Jiamin Liu Jinlong Zhu +8 位作者 Zhe Yu Xianrui Feng Zedi Li Lei Zhong Jinsong Zhang Honggang Gu Xiuguo Chen Hao Jiang Shiyuan Liu 《International Journal of Extreme Manufacturing》 2025年第1期623-639,共17页
In integrated circuit(IC)manufacturing,fast,nondestructive,and precise detection of defects in patterned wafers,realized by bright-field microscopy,is one of the critical factors for ensuring the final performance and... In integrated circuit(IC)manufacturing,fast,nondestructive,and precise detection of defects in patterned wafers,realized by bright-field microscopy,is one of the critical factors for ensuring the final performance and yields of chips.With the critical dimensions of IC nanostructures continuing to shrink,directly imaging or classifying deep-subwavelength defects by bright-field microscopy is challenging due to the well-known diffraction barrier,the weak scattering effect,and the faint correlation between the scattering cross-section and the defect morphology.Herein,we propose an optical far-field inspection method based on the form-birefringence scattering imaging of the defective nanostructure,which can identify and classify various defects without requiring optical super-resolution.The technique is built upon the principle of breaking the optical form birefringence of the original periodic nanostructures by the defect perturbation under the anisotropic illumination modes,such as the orthogonally polarized plane waves,then combined with the high-order difference of far-field images.We validated the feasibility and effectiveness of the proposed method in detecting deep subwavelength defects through rigid vector imaging modeling and optical detection experiments of various defective nanostructures based on polarization microscopy.On this basis,an intelligent classification algorithm for typical patterned defects based on a dual-channel AlexNet neural network has been proposed,stabilizing the classification accuracy ofλ/16-sized defects with highly similar features at more than 90%.The strong classification capability of the two-channel network on typical patterned defects can be attributed to the high-order difference image and its transverse gradient being used as the network’s input,which highlights the polarization modulation difference between different patterned defects more significantly than conventional bright-field microscopy results.This work will provide a new but easy-to-operate method for detecting and classifying deep-subwavelength defects in patterned wafers or photomasks,which thus endows current online inspection equipment with more missions in advanced IC manufacturing. 展开更多
关键词 defect inspection form birefringence breaking high order difference anisotropic illumination modes deep-subwavelength sensitivity defect classification
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Breaking barriers: MS-BDF tools in the quality control of insect-derived traditional Chinese medicine 被引量:1
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作者 Caixia Yuan Dandan Zhang +2 位作者 Hairong Zhang Jiyang Dong Caisheng Wu 《Journal of Pharmaceutical Analysis》 2025年第6期1403-1405,共3页
Insect-derived traditional Chinese medicine(TCM)constitutes an essential component of TCM,with the earliest records found in“52 Bingfang”(Prescriptions of fifty-two diseases,which is one of the earliest Chinese medi... Insect-derived traditional Chinese medicine(TCM)constitutes an essential component of TCM,with the earliest records found in“52 Bingfang”(Prescriptions of fifty-two diseases,which is one of the earliest Chinese medical prescriptions). 展开更多
关键词 traditional chinese medicine tcm constitutes chinese medical prescriptions prescriptions fifty two diseases ms bdf tools insect derived traditional chinese medicine quality control breaking barriers TCM
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Interpretable machine learning for chiral induced symmetry breaking of spin density boosting hydrogen evolution
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作者 Xin Song Zhonghua Li +1 位作者 Li Sheng Yang Liu 《Journal of Energy Chemistry》 2025年第4期68-78,共11页
The integration of machine learning and electrocatalysis presents nota ble advancements in designing and predicting the performance of chiral materials for hydrogen evolution reactions(HER).This study utilizes theoret... The integration of machine learning and electrocatalysis presents nota ble advancements in designing and predicting the performance of chiral materials for hydrogen evolution reactions(HER).This study utilizes theoretical calculations and machine learning techniques to assess the HER performance of both chiral and achiral M-N-SWCNTs(M=In,Bi,and Sb)single-atom catalysts(SACs).The stability preferences of metal atoms are dependent on chirality when interacting with chiral SWCNTs.The HER activity of the right-handed In-N-SWCNT is 5.71 times greater than its achiral counterpart,whereas the left-handed In-N-SWCNT exhibits a 5.12-fold enhancement.The calculated hydrogen adsorption free energy for the right-handed In-N-SWCNT reaches as low as-0.02 eV.This enhancement is attributed to the symmetry breaking in spin density distribution,transitioning from C_(2V)in achiral SACs to C_(2)in chiral SACs,which facilitates active site transfer and enhances local spin density.Right-handed M-N-SWCNTs exhibit superiorα-electron separation and transport efficiency relative to left-handed variants,owing to the chiral induced spin selectivity(CISS)effect,with spin-upα-electron density reaching 3.43×10^(-3)e/Bohr^(3)at active sites.Machine learning provides deeper insights,revealing that the interplay of weak spatial electronic effects and appropriate curvature-chirality effects significantly enhances HER performance.A weaker spatial electronic effect correlates with higher HER activity,larger exchange current density,and higher turnover frequency.The curvature-chirality effect undersco res the influence of intrinsic structures on HER performance.These findings offer critical insights into the role of chirality in electrocatalysis and propose innovative approaches for optimizing HER through chirality. 展开更多
关键词 Symmetry breaking Machine learning Spin density CISS DFT Hydrogen evolution reaction
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Study on the Breaking Force and Efficacy Evaluation of Lipsticks Containing Carnauba Wax and Shea Butter
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作者 Zi Yusha Liu Jianwei +4 位作者 Jiang Xiuyu Hu Weiren Sheng Wenli Gui Yuhao Peng Xianwu 《China Detergent & Cosmetics》 2025年第2期56-61,共6页
Starting from the perspective of formula and efficacy,orthogonal experiments were first performed to explore the optimal ratio of three raw materials that potentially affect breaking force of lipsticks,verification ex... Starting from the perspective of formula and efficacy,orthogonal experiments were first performed to explore the optimal ratio of three raw materials that potentially affect breaking force of lipsticks,verification experiment on humans was then conducted to test the efficacy of the lipstick formula.Results showed that when the ratio of carnauba wax,shea butter and myristyl isopropyl ester was 3∶7∶3,the breaking force was optimal.After the subjects used the lipstick formula for 14 days,the moisture content of the lip stratum corneum significantly increased by 23.51% (P﹤0.05),the transepidermal water loss (TEWL) rate significantly decreased by 20.61%,the skin glossiness increased significantly by 9.88%,and the skin scale index decreased significantly by 55.76%. 展开更多
关键词 carnauba wax shea butter breaking strength lipsticks
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Impact rock-breaking mechanisms and energy transfer laws of conical tooth bits in hot dry rocks
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作者 LIU Qingyou HUANG Tao 《Petroleum Exploration and Development》 2025年第4期1053-1063,共11页
Based on the finite-discrete element method,a three-dimensional numerical model for axial impact rock breaking was established and validated.A computational method for energy conversion during impact rock breaking was... Based on the finite-discrete element method,a three-dimensional numerical model for axial impact rock breaking was established and validated.A computational method for energy conversion during impact rock breaking was proposed,and the effects of conical tooth forward rake angle,rock temperature,and impact velocity on rock breaking characteristics and energy transfer laws were analyzed.The results show that during single impact rock breaking with conical tooth bits,merely 7.52%to 12.51%of the energy is utilized for rock breaking,while a significant 57.26%to 78.10%is dissipated as frictional loss.An insufficient forward rake angle increases tooth penetration depth and frictional loss,whereas an excessive forward rake angle reduces penetration capability,causing bit rebound and greater energy absorption by the drill rod.Thus,an optimal forward rake angle exists.Regarding environmental factors,high temperatures significantly enhance impact-induced rock breaking.Thermal damage from high temperatures reduces rock strength and inhibits its energy absorption.Finally,higher impact velocities intensify rock damage,yet excessively high velocities increase frictional loss and reduce the proportion of energy absorbed by the rock,thereby failing to substantially improve rock breaking efficiency.An optimal impact velocity exists. 展开更多
关键词 hot dry rock finite-discrete element method conical tooth bit forward rake angle impact velocity rock temperature energy transfer rock breaking mechanism
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Universal Behavior in Entanglement Entropy Reveals Quantum Criticality and Underlying Symmetry Breaking
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作者 Zhe Wang Zehui Deng +5 位作者 Zenan Liu Zhiyan Wang Yi-Ming Ding Long Zhang Wenan Guo Zheng Yan 《Chinese Physics Letters》 2025年第11期341-353,共13页
Entanglement plays a key role in quantum physics, but how much information it can extract from many-body systems is still an open question, particularly regarding quantum criticalities and emergent symmetries. In this... Entanglement plays a key role in quantum physics, but how much information it can extract from many-body systems is still an open question, particularly regarding quantum criticalities and emergent symmetries. In this work, we systematically study the entanglement entropy(EE) and derivative entanglement entropy(DEE) near quantum phase transitions in various quantum many-body systems. A one-parameter scaling relation between the DEE and system size at the critical point has been derived for the first time, which successfully obtains the critical exponent via data collapse. Furthermore, we find that the EE peaks at the(emergent) symmetryenhanced first-order transition, reflecting higher symmetry breaking. This work provides a new paradigm for quantum many-body research from the perspective of EE and DEE. 展开更多
关键词 quantum criticalities derivative entanglement entropy dee entanglement entropy derivative entanglement entropy entanglement entropy ee symmetry breaking emergent symmetries quantum physics
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The flow field characteristics and rock breaking ability of cone-straight abrasive jet,rotary abrasive jet,and straight-rotating mixed abrasive jet
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作者 Jing-Bin Li Ergun Kuru +3 位作者 Wen-Bin Li Chen-Rui Guo Gen-Sheng Li Zhong-Wei Huang 《Petroleum Science》 2025年第6期2457-2464,共8页
Radial jet drilling(RJD)technology is expected to be a technology for the efficient exploitation of geothermal resources.However,the low rock-breaking efficiency is the major obstacle hindering the development of RJD ... Radial jet drilling(RJD)technology is expected to be a technology for the efficient exploitation of geothermal resources.However,the low rock-breaking efficiency is the major obstacle hindering the development of RJD technology.The flow field characteristics and rock breaking ability of cone-straight abrasive jet,rotary abrasive jet,and straight-rotating mixed abrasive jet are analyzed by numerical simulations and experiments.Results show that the axial velocity of the cone-straight abrasive jet is high,the tangential velocity is basically zero,the radial velocity is also small,and the jet impact area is concentrated in the center.A deep hole with a diameter of only 25 mm is formed when the cone-straight abrasive jet breaks the granite.Due to the presence of the guiding impeller,the rotary abrasive jet basically has no axial velocity and has the highest tangential and radial velocity,so it can break the granite to form a hole with a diameter of about 55 mm and a central bulge.The straight-rotating mixed abrasive jet has a large axial/tangential/radial velocity at the same time,so it can break the granite to form a hole with a diameter of about 52 mm with a low bulge.The results show that the straight-rotating mixed abrasive jet combines the advantages of the cone-straight jet and the rotary jet,and is more suitable for the RJD technology.The research results can provide reference for the development of efficient rock-breaking and hole-forming technology,and promote the development of RJD technology in the field of geothermal development. 展开更多
关键词 Geothermal resources Radial jet drilling Abrasive water jet Flow field simulation Rock breaking ability
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Magnetic resonance cholangiopancreatography and laparoscopic bile duct exploration should be standard procedures for patients with the ice-breaking sign?
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作者 Lucia Mejuto Maria Delgado Luis R Rabago 《World Journal of Gastrointestinal Surgery》 2025年第11期12-16,共5页
The authors introduce a new magnetic resonance cholangiopancreatography(MRCP)radiologic feature,the“ice-breaking sign”(IBS),and present a retrospective case-control study comparing patients with common bile duct sto... The authors introduce a new magnetic resonance cholangiopancreatography(MRCP)radiologic feature,the“ice-breaking sign”(IBS),and present a retrospective case-control study comparing patients with common bile duct stones who exhibit the IBS with a control group without this sign.The two groups were matched using a propensity score based on patient age and sex.However,the matching process did not account for the size of the choledocholithiasis,which may represent a significant confounding factor.Both groups were not homogeneous.The authors advocate for the use of MRCP as the primary diagnostic tool to guide the decision.However,in clinical practice,MRCP availability is often limited,particularly when compared to endoscopic ultrasound,which may be more available.The authors compared the clinical course and therapeutic responses to cholangiopancreatography(ERCP)and laparoscopic common bile duct exploration(LCBDE)between the two groups.The results demonstrated a markedly low ERCP success rate in both the study and control,falling below international standards,whereas the success rate of LCBDE was only slightly reduced.Despite the study’s li-mitations and potential biases,the authors conclude that IBS is a valuable predictor for treatment planning and suggest that LCBDE should be considered the first-line approach.Despite its growing acceptance,LCBDE remains infeasible in many hospitals due to the steep learning curve. 展开更多
关键词 Ice breaking sign Magnetic resonance cholangiopancreatography CHOLEDOCHOLITHIASIS Laparoscopic bile duct exploration Common bile duct stones treatment Endoscopic retrograde cholangiopancreatography
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Symmetry Breaking Dynamics in Quantum Many-Body Systems
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作者 Hui Yu Zi-Xiang Li Shi-Xin Zhang 《Chinese Physics Letters》 2025年第11期150-173,共24页
Entanglement asymmetry(EA) has emerged as a powerful tool for characterizing symmetry breaking in quantum many-body systems. In this Letter, we explore how symmetry is dynamically broken through the lens of EA in two ... Entanglement asymmetry(EA) has emerged as a powerful tool for characterizing symmetry breaking in quantum many-body systems. In this Letter, we explore how symmetry is dynamically broken through the lens of EA in two distinct scenarios: a non-symmetric Hamiltonian quench and a non-symmetric random quantum circuit, with a particular focus on U(1) symmetry. In the former case, symmetry remains broken in the subsystem at late times, whereas in the latter case, the symmetry is initially broken and subsequently restored, consistent with the principles of quantum thermalization. Notably, the growth of EA exhibits unexpected overshooting behavior at early times in both contexts, contrasting with the behavior of charge variance. We also consider dynamics of non-symmetric initial states under the symmetry-breaking evolution. Due to the competition of symmetry-breaking in both the initial state and Hamiltonian, the early-time EA can increase and decrease, while quantum Mpemba effects remain evident despite the weak symmetry-breaking in both settings. 展开更多
关键词 entanglement asymmetry quantum circuit symmetry breaking quantum many body systems non symmetric Hamiltonian quench quantum thermalization non symmetric random quantum circuit entanglement asymmetry ea
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A groundbreaking work bridging theory and practice:A review of Urbanization and Production of Space:A Multi-scalar Empirical Study Based on China's Cases
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作者 Uchendu Eugene Chigbu 《Journal of Geographical Sciences》 2025年第2期455-456,共2页
At its core,Urbanization and Production of Space provides a comprehensive analysis of the intricate relationship between urbanization and the production of space,particularly within the rapidly evolving context of Chi... At its core,Urbanization and Production of Space provides a comprehensive analysis of the intricate relationship between urbanization and the production of space,particularly within the rapidly evolving context of China's urban transformation.As one of the most populous and dynamically urbanizing nations,China serves as a compelling case for understanding the broader global implications of spatial restructuring. 展开更多
关键词 URBANIZATION transformation breaking
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Symmetry-Breaking Strain Drives Significant Reduction in Lattice Thermal Conductivity:A Case Study of Boron Arsenide
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作者 Kaile Chen Xin Jin Xiaolong Yang 《Chinese Physics Letters》 2025年第12期358-374,共17页
Recent research has revealed that cubic boron arsenide(BAs)exhibits a non-monotonic pressure dependence of lattice thermal conductivity(κ_(L))under isotropic strain.Here,through rigorous first-principles calculations... Recent research has revealed that cubic boron arsenide(BAs)exhibits a non-monotonic pressure dependence of lattice thermal conductivity(κ_(L))under isotropic strain.Here,through rigorous first-principles calculations,we unveil that anisotropic strain induces a monotonic reduction in the κ_(L) of BAs-a striking contrast to the isotropic scenario.The results show that applying uniaxial[100]strain leads to the lifting of phonon band degeneracy,accompanied by an overall softening of the phonon spectrum.These modifications significantly increase phonon-phonon scattering channels by facilitating the fulfillment of selection rules,resulting in a concurrent increase in both three-and four-phonon scattering rates.Consequently,κ_(L) exhibits a dramatic suppression of nearly 80%under large tension at room temperature.Meanwhile,we unexpectedly observe that the uniaxial strain suppresses κ_(L) much more strongly in the direction perpendicular to the strain than along the stretching direction.This work establishes the fundamental understanding of the thermal conductivity behavior of BAs under anisotropic strain and opens a promising avenue for manipulating solid-state heat transport by tuning lattice crystal symmetry. 展开更多
关键词 phonon band degeneracy lifting phonon band degeneracyaccompanied softening phonon spectrumthese boron arsenide boron arsenide bas exhibits lattice thermal conductivity symmetry breaking strain anisotropic strain
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Record-breaking bifunctional oxygen electrocatalyst accomplished by a data-driven approach for zinc-air batteries
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作者 Deviprasath Chinnadurai Zhi Wei Seh 《Journal of Energy Chemistry》 2025年第1期144-145,共2页
Rechargeable zinc-air batteries(ZABs) have recently drawn great attention in energy research due to their high theoretical capacity,low costs, and inherently safe nature [1–3]. However, the sluggish cathode reactions... Rechargeable zinc-air batteries(ZABs) have recently drawn great attention in energy research due to their high theoretical capacity,low costs, and inherently safe nature [1–3]. However, the sluggish cathode reactions necessitate the development of bifunctional oxygen electrocatalysts with lower ΔE indicator values. The ΔE indicator is commonly employed to quantitatively evaluate the electrocatalytic activity of a bifunctional oxygen electrocatalyst,representing the overall overpotential from oxygen reduction reaction(ORR) to oxygen evolution reaction(OER). 展开更多
关键词 breaking representing accomplished
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Scanning tunneling microscopy study on symmetry breaking of charge density wave in FeGe
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作者 Jiakang Zhang Ziyuan Chen +8 位作者 Xueliang Wu Mingzhe Li Yuanji Li Ruotong Yin Jiashuo Gong Shiyuan Wang Aifeng Wang Dong-Lai Feng Ya-Jun Yan 《Chinese Physics B》 2025年第4期55-61,共7页
The complex symmetry breaking states in AV3Sb5 family have attracted extreme research attention,but controversy still exists,especially in the question of time reversal symmetry breaking of the charge density wave(CDW... The complex symmetry breaking states in AV3Sb5 family have attracted extreme research attention,but controversy still exists,especially in the question of time reversal symmetry breaking of the charge density wave(CDW).Most recently,a chiral CDW has been suggested in kagome magnet FeGe,but the related study is very rare.Here,we use a scanning tunneling microscope to study the symmetry breaking behavior of both the short-and long-range CDWs in FeGe.Different from previous studies,our study reveals an isotropic long-range CDW without obvious symmetry breaking,while local rotational symmetry breaking appears in the short-range CDW,which may be related to the existence of strong structural disorders.Moreover,the charge distribution of the short-range CDW is inert to the applied external magnetic fields and the detailed spin arrangements of FeGe,inconsistent with the expectation of a chiral CDW associated with chiral flux.Our results rule out the existence of spontaneous chiral and rotational symmetry breaking in the CDW state of FeGe,putting strong constraints on the further understanding of CDW mechanism. 展开更多
关键词 symmetry breaking kagome magnet charge density wave
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On-Chip Degeneracy Breaking of Wood’s Anomaly for Vibrational Strong Coupling
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作者 Xing Liu Shu Chen +3 位作者 Hao Wang Chengxiao Song Tinghui Xiao Chongxin Shan 《Chinese Physics Letters》 2025年第9期34-49,共16页
Vibrational strong coupling(VSC)provides a promising way towards not only enhanced control of infrared light but also reshaping of molecular properties,which opens up unprecedented opportunities in ultrasensitive infr... Vibrational strong coupling(VSC)provides a promising way towards not only enhanced control of infrared light but also reshaping of molecular properties,which opens up unprecedented opportunities in ultrasensitive infrared spectroscopy,modification of chemical reactions,and exploration of nonlinear quantum effects.Surface plasmon resonance,excited on simple plasmonic resonators in the infrared,has been demonstrated as a means to realize VSC,but suffers from either limited quality factor for realizing large Rabi splitting or poor reconfigurability for precise detuning control.Here we propose and experimentally demonstrate,for the first time,an on-chip plasmonic resonator based on degeneracy breaking of Wood’s anomaly for VSC.Leveraging the low damping rate of the surface state induced by this degeneracy breaking,we achieve a plasmonic resonance with a high-Q factor exceeding~110,resulting in a Rabi splitting up to~112 cm^(-1) with a subwavelength molecular layer.Additionally,the dispersion of the surface state allows for precise control over VSC detuning by simply adjusting the incident angle of excitation light,even in the absence of photons,enabling a broad detuning range up to 300 cm^(-1).These experimental results align well with our analytical model and numerical simulation.This work provides a promising integrated platform for VSC,with various potential applications in on-chip spectroscopy,polariton chemistry,and polariton devices. 展开更多
关键词 plasmonic resonators exploration nonlinear quantum effectssurface plasmon resonanceexcited vibrational strong coupling vsc provides vibrational strong coupling ultrasensitive infrared spectroscopymodification chemical reactionsand chip degeneracy breaking reshaping molecular propertieswhich enhanced control infrared light
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Tunneling conductance in ferromagnet/superconductor junctions with time-reversal symmetry breaking
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作者 Li Hong Xin Jian Yang 《Communications in Theoretical Physics》 2025年第4期151-158,共8页
The tunneling conductance of two kinds of tunnel junctions with time-reversal symmetry breaking,normal metal/insulator/ferromagnetic metal/dx_(2-y2)+is-wave superconductor(NM/I/FM/dx_(2-y2)+is-wave SC)and NM/I/FM/dx_(... The tunneling conductance of two kinds of tunnel junctions with time-reversal symmetry breaking,normal metal/insulator/ferromagnetic metal/dx_(2-y2)+is-wave superconductor(NM/I/FM/dx_(2-y2)+is-wave SC)and NM/I/FM/dx_(2-y2)+idxy-wave SC,is calculated using the extended Blonder-Tinkham-Klapwijk theoretical method.The ratio of the subdominant s-wave and dxy-wave components to the dominant dx_(2-y2)-wave component is expressed byΔ_(s)/Δ_(D)andΔ_(d)/Δ_(D),respectively.Results show that for NM/I/FM/dx_(2-y2)+is-wave SC tunnel junctions,the splitting of the zero-bias conductance peak(ZBCP)is obtained and the splitting peaks appear at eV/Δ_(0)=±Δ_(s)/Δ_(D)with eV the applied bias voltage andΔ_(0)the zero temperature energy gap of SC.For NM/I/FM/dx_(2-y2)+idxy-wave SC tunnel junctions,there are also conductance peaks at eV/Δ_(0)=±Δ_(d)/Δ_(D)but the ZBCP does not split.For the two types of tunnel junctions,the completely reversed tunnel conductance spectrum indicates that when the exchange energy in FM is increased to a certain value,the proximity effect transforms the tunnel junctions from the'0 state'to the'πstate'.The shortening of the transport quasiparticle lifetime can weaken the proximity effect to smooth out the dips and peaks in the tunnel spectrum.This is considered a possible reason that the ZBCP splitting was not observed in some previous experiments.It is expected that these analysis results can serve as a guide for future experiments and the relevant conclusions can be confirmed. 展开更多
关键词 dx^(2)+y^(2)+is-wave dx^(2)+y^(2)+id_(ay)-wave time-reversal symmetry breaking quasiparticle lifetime effect proximity effect
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Factor analysis and numerical simulation of rock breaking efficiency of TBM deep rock mass based on orthogonal design 被引量:4
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作者 LI Xiao-jing ZHANG Hua-ken +1 位作者 BAI Yi-fan ZHANG Xiang-yang 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第4期1345-1362,共18页
This study investigates the factors affecting the rock-breaking efficiency of the TBM disc cutter in deep rock excavation,including confining pressure,penetration,cutter spacing,and revolution speed.The finite element... This study investigates the factors affecting the rock-breaking efficiency of the TBM disc cutter in deep rock excavation,including confining pressure,penetration,cutter spacing,and revolution speed.The finite element method is employed to formulate a rock-breaking model of the rotary disc cutters and a numerical simulation is also implemented.The rock breaking effect,rock breaking volume,and rock breaking specific energy consumption under different combinations of the factors are investigated.An orthogonal test of four factors at four levels was constructed.Based on the test results and range analysis in the process of deep rock mass breaking,the order of sensitivity of each influencing factor with respect to the rock breaking specific energy for the disc cutter is cutter spacing>revolution speed>penetration>confining pressure.By constructing a numerical simulation comparison scheme,the orthogonal test results are analyzed and corroborated,and the rock breaking law and rock breaking efficiency under different influencing factors are derived.Finally,the sensitivity of different influencing factors on the rock-breaking efficiency is verified. 展开更多
关键词 deep rock mass TBM rock breaking rock breaking specific energy rock breaking efficiency
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Intermittency of Wind Wave Group Breaking
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作者 类淑河 薛川 +1 位作者 田文婧 管长龙 《China Ocean Engineering》 SCIE EI CSCD 2013年第5期605-614,共10页
Knowledge on intermittency of wave breaking is so far limited to a few summary statistics, while the probability distribution of time interval between breaking events can provide a full view of intermittency. Based on... Knowledge on intermittency of wave breaking is so far limited to a few summary statistics, while the probability distribution of time interval between breaking events can provide a full view of intermittency. Based on a series of experiments on wind wave breaking, such probability distributions are investigated. Breaking waves within a wave group were taken as a single breaking event according to recent studies. Interval between successive wave groups with breaker is the focus of this paper. For intervals in our experiments with different fetch and wind conditions, their distributions are all skewed and weighted on small intervals. Results of Kolmogorov-Smirnov tests on time series of these intervals indicate that they all follow gamma distribution, and some are even exponential type. Average breaking-group-interval decreases with friction velocity and significant steepness until the wind is strong enough;most of them are more than 10 times the dominant wave period. Group breaking probability proposed by Babanin recently and the average number of breaking waves in wave groups are also discussed, and they are seemingly more reasonable and sensitive than traditional breaking probability defined in terms of single wave. 展开更多
关键词 wave breaking wave group group breaking probability breaking group interval gamma distribution
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Determining the Onset and Strength of Unforced Wave Breaking in A Numerical Wave Tank 被引量:2
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作者 何海伦 宋金宝 《China Ocean Engineering》 SCIE EI CSCD 2014年第4期501-509,共9页
A numerical wave tank is used to investigate the onset and strength of unforced wave breaking, and the waves have three types of initial spectra: constant amplitude spectrum, constant steepness spectrum and Pierson-M... A numerical wave tank is used to investigate the onset and strength of unforced wave breaking, and the waves have three types of initial spectra: constant amplitude spectrum, constant steepness spectrum and Pierson-Moscowitz spectrum. Numerical tests are performed to validate the model results. Then, the onset of wave breaking is discussed with geometric, kinematic, and dynamic breaking criteria. The strength of wave breaking, which is always characterized by the fractional energy loss and breaking strength coefficient, is studied for different spectra. The results show how the energy growth rate is better than the initial wave steepness on estimating the fractional energy losses as well as breaking strength coefficient. 展开更多
关键词 wave breaking numerical wave tank fractional energy loss breaking strength coefficient
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Probabilistic Models for the Probability of Wave Breaking and Whitecap Coverage Based on Kinematic Breaking Criterion 被引量:1
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作者 郑桂珍 徐德伦 《海洋工程:英文版》 EI 2004年第3期357-370,共14页
More and more researches show that neither the critical downward acceleration nor the critical slope of water waves is a universal constant. On the contrary, they vary with particular wave conditions. This fact render... More and more researches show that neither the critical downward acceleration nor the critical slope of water waves is a universal constant. On the contrary, they vary with particular wave conditions. This fact renders the models either for the probability of wave breaking B or for the whitecap coverage W based on these criteria difficult to apply. In this paper and the one which follows we seek to develop models for the prediction of both B and W based on the kinematical criterion. First, several joint probabilistic distribution functions (PDFs) of wave characteristics are derived, based on which the breaking properties B and W are estimated. The estimation is made on the assumption that a wave breaks if the horizontal velocity of water particles at its crest exceeds the local wave celerity, and whitecapping occurs in regions of fluid where water particles travel faster than the waves. The consequent B and W depend on wave spectral moments of orders 0 to 4. Then the JONSWAP spectrum is used to represent the fetch limited sea waves in deep water, so as to relate the probability of wave breaking and the whitecap coverage with wind parameters. To this end, the time averaging technique proposed by Glazman (1986) is applied to the estimation of the spectral moments involved, and furthermore, the theoretical models are compared with available observations collected from published literature. From the comparison, the averaging time scale is determined. The final models show that the probability of wave breaking as well as the whitecap coverage depends on the dimensionless fetch. The agreement between these models and the database is reasonable. 展开更多
关键词 wave statistics wave breaking probability of wave breaking whitecap coverage spectral moment
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Singularity and Breaking of the Third Order Stokes Waves 被引量:1
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作者 孙孚 高山 +1 位作者 王伟 钱成春 《海洋工程:英文版》 2003年第1期111-116,共6页
In this paper, the fact is revealed that the surface elevation of the third order Stokes waves in implicit form could have no solution or have simultaneously a trivial one and a singular one on certain conditions. Bas... In this paper, the fact is revealed that the surface elevation of the third order Stokes waves in implicit form could have no solution or have simultaneously a trivial one and a singular one on certain conditions. Based on this fact, the relative breaking width, a more reasonable quantity in agreement with the definition of whitecapping coverage rate, is obtained directly from the assumption that no solution means breaking. The implications of the singular solution existing in the third order stokes waves are also discussed briefly. 展开更多
关键词 Stokes waves breaking criterion breaking width SINGULARITY
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