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Local Rotational Jamming and Multi-Stage Hyperuniformities in an Active Spinner System 被引量:1
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作者 刘锐 巩建晓 +1 位作者 杨明成 陈科 《Chinese Physics Letters》 SCIE EI CAS CSCD 2023年第12期104-108,共5页
An active system consisting of many self-spinning dimers is simulated, and a distinct local rotational jamming transition is observed as the density increases. In the low density regime, the system stays in an absorbi... An active system consisting of many self-spinning dimers is simulated, and a distinct local rotational jamming transition is observed as the density increases. In the low density regime, the system stays in an absorbing state,in which each dimer rotates independently subject to the applied torque;while in the high density regime,a fraction of the dimers become rotationally jammed into local clusters, and the system exhibits microphaseseparation like two-phase morphologies. For high enough densities, the system becomes completely jammed in both rotational and translational degrees of freedom. Such a simple system is found to exhibit rich and multiscale disordered hyperuniformities among the above phases: the absorbing state shows a critical hyperuniformity of the strongest class and subcritically preserves the vanishing density fluctuation scaling up to some length scale;the locally jammed state shows a two-phase hyperuniformity conversely beyond some length scale with respect to the phase cluster sizes;the totally jammed state appears to be a monomer crystal, but intrinsically loses large-scale hyperuniformity. These results are inspiring for designing novel phase-separation and disordered hyperuniform systems through dynamical organization. 展开更多
关键词 UNIFORM SYSTEM ROTATIONAL
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Enhanced Convective Heat Transfer in Pyrolysis Furnaces via Impeller-Induced Stirring
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作者 Hongyun Bai Jianxin Xu +4 位作者 Wenbo Shi Xiaowei Ma Jun Ma Shaoyin Zhu Hua Wang 《Fluid Dynamics & Materials Processing》 2026年第2期179-204,共26页
Optimizing pyrolysis processes is critical for improving the efficiency of pyrolysis furnaces.This study presents a strategy to enhance heat transfer through agitation,employing Fluent for detailed numerical simulatio... Optimizing pyrolysis processes is critical for improving the efficiency of pyrolysis furnaces.This study presents a strategy to enhance heat transfer through agitation,employing Fluent for detailed numerical simulation of the thermal behavior.The simulation results show strong agreement with experimental measurements of localized fluid temperature rise.Forced convection induced by impeller rotation significantly improves heat transfer between the fluid and the furnace walls,effectively reducing thermal stratification.At an impeller speed of 240 RPM,the axial temperature difference decreases from 200 K to 50 K compared with stationary conditions,while the average heat transfer coefficient increases by approximately 50%throughout the heating process.The swirl flow generated by impeller motion disrupts the thermal boundary layer,achieving a more uniform temperature distribution and faster thermal response. 展开更多
关键词 Furnace temperature control natural convection numerical simulation STIRRING temperature uniformity
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Stress Uniformity and Dynamic Mechanical Properties of Cubic Concretes in SHPB Tests
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作者 LI Mei CUI Jian +1 位作者 SHI Yanchao TANG Baijian 《Journal of Wuhan University of Technology(Materials Science)》 2026年第1期162-170,共9页
Based on the split hopkinson pressure bar(SHPB)tests results,the cubic specimens have been numerically modeled in this paper to investigate the impact of key factors,such as the rise time,duration,and incident pulse s... Based on the split hopkinson pressure bar(SHPB)tests results,the cubic specimens have been numerically modeled in this paper to investigate the impact of key factors,such as the rise time,duration,and incident pulse shape,on achieving stress uniformity.After analysis,the paper provides actionable methods aimed at optimizing the conditions for stress uniformity within the cubic specimen.Finally,the lateral inertia effect of cubic specimen has been scrutinized to address the existing gap in this academic area. 展开更多
关键词 concrete cubic specimen stress uniformity impact loads lateral inertia effect
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Uniform Attractors for the Kirchhoff Type Suspension Bridge Equation with Nonlinear Damping and Memory Term
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作者 Ling XU Yanni WANG 《Journal of Mathematical Research with Applications》 2026年第1期71-86,共16页
The goal of this paper is to investigate the long-time dynamics of solutions to a Kirchhoff type suspension bridge equation with nonlinear damping and memory term.For this problem we establish the well-posedness and e... The goal of this paper is to investigate the long-time dynamics of solutions to a Kirchhoff type suspension bridge equation with nonlinear damping and memory term.For this problem we establish the well-posedness and existence of uniform attractor under some suitable assumptions on the nonlinear term g(u),the nonlinear damping f(u_(t))and the external force h(x,t).Specifically,the asymptotic compactness of the semigroup is verified by the energy reconstruction method. 展开更多
关键词 uniform attractor Kirchhoff type suspension bridge equation nonlinear damping memory term
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Effects of coil structure and electromagnetic shielding on plasma distribution and uniformity in large-area radio-frequency inductively coupled plasmas
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作者 Cheng Xin Xiang-Yun Lyu +5 位作者 Si-Yu Xing Yu-Ru Zhang Tao Liu Wei-Ping Le Fei Gao You-Nian Wang 《Chinese Physics B》 2026年第2期233-246,共14页
Improving plasma uniformity is a critical issue in the development of large-area radio-frequency(RF)inductively coupled plasma(ICP)sources.In this work,the effects of coil structure and electromagnetic shielding on th... Improving plasma uniformity is a critical issue in the development of large-area radio-frequency(RF)inductively coupled plasma(ICP)sources.In this work,the effects of coil structure and electromagnetic shielding on the spatial distribution and uniformity of the plasma are systematically investigated using a three-dimensional fluid model.The model integrates plasma and electromagnetic field modules to simulate the discharge characteristics of a large-area RF ICP source with dimensions of 100 cm×50 cm.The results reveal that the electron density distribution varies significantly with the coil structure.For the rotating and translating coil structures,the electron density is high at off-axis positions and low at the center.In contrast,the mirror coil structure exhibits a significantly higher electron density at the chamber center,resulting in a high-center and low-edge density distribution.Among the three configurations,the rotating coil structure provides the best plasma uniformity.The incorporation of electromagnetic shielding further improves plasma uniformity,particularly for the mirror coil structure.For the rotating and translating coil structures,the electron density exhibits a saddle-shaped distribution regardless of electromagnetic shielding.However,introducing electromagnetic shielding into the mirror coil structure reduces the electron density at the chamber center and decreases the non-uniformity degree by 18.4%.Overall,the mirror coil structure with electromagnetic shielding achieves the highest uniformity,with an exceptional plasma uniformity of 94%.This work offers valuable insights for the design of large-area ICP sources in advanced plasma processing systems. 展开更多
关键词 large-area radio-frequency inductively coupled plasma three-dimensional fluid model plasma uniformity
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Suppression of ablative Rayleigh–Taylor instability by spatially modulated laser in inertial confinement fusion
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作者 Zhantao Lu Xinglong Xie +10 位作者 Xiao Liang Meizhi Sun Ping Zhu Xuejie Zhang Chunqing Xing Linjun Li Hao Xue Guoli Zhang Rashid Ul Haq Dongjun Zhang Jianqiang Zhu 《Matter and Radiation at Extremes》 2026年第1期29-38,共10页
The suppression of ablative Rayleigh–Taylor instability(ARTI)by a spatially modulated laser in inertial confinement fusion(ICF)is studied through numerical simulations.The results show that in the acceleration phase ... The suppression of ablative Rayleigh–Taylor instability(ARTI)by a spatially modulated laser in inertial confinement fusion(ICF)is studied through numerical simulations.The results show that in the acceleration phase of ICF implosion,the growth of ARTI can be suppressed by using a short-wavelength spatially modulated laser.The ARTI growth rate decreases as the wavelength of the spatially modulated laser decreases,and ARTI is completely suppressed after a certain wavelength has been reached.A spatially uniform laser is introduced to keep the state of motion of the implosion fluid consistent,and it is found that the proportion of the spatially modulated laser required for complete suppression of ARTI decreases as the wavelength continues to decrease.We also optimize the spatial intensity distribution of the spatially modulated laser.In addition,as the duration of the spatially modulated laser decreases,the proportion required for completely suppressing ARTI increases,but the required energy decreases.When the perturbation wavenumber decreases,the wavelength of the spatially modulated laser required for complete suppression of ARTI becomes longer.In the case of multimode perturbation,ARTI can also be significantly suppressed by a spatially modulated laser,and the perturbation amplitude can be reduced to less than 10% of that without a spatially modulated laser.We believe that the conclusions drawn from our simulations can provide the basis for new approaches to control ARTI in ICF. 展开更多
关键词 ablative Rayleigh Taylor instability ablative rayleigh taylor instability arti numerical simulationsthe spatially modulated laser inertial confinement fusion icf spatially modulated laserthe acceleration phase spatially uniform
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Pointwise uniformities and pointwise metrics on fuzzy lattices 被引量:5
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作者 SHI FuguiDepartment of Mathematics, Yantai Teachers College, Yantai 264025, China 《Chinese Science Bulletin》 SCIE EI CAS 1997年第9期718-720,共3页
UP till now there has been much spectacular and creative work about the theories of uniformi-ties and metrics in topological lattice.But this is mostly generalizations and developmentsof Hutton’s and Erceg’s pointle... UP till now there has been much spectacular and creative work about the theories of uniformi-ties and metrics in topological lattice.But this is mostly generalizations and developmentsof Hutton’s and Erceg’s pointless work.They cannot directly reflect the characteristics ofpointwise topology.In this note we shall set up a theory of pointwise uniformity and a theoryof pointwise metric on fuzzy lattices. 展开更多
关键词 fuzzy LATTICE POINTWISE UNIFORMITY POINTWISE metric COMPLETE REGULARITY remote-neighborhood mapping.
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On the differential uniformities of functions over finite fields 被引量:4
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作者 QU LongJiang LI Chao +1 位作者 DAI QingPing KONG ZhiYin 《Science China Mathematics》 SCIE 2013年第7期1477-1484,共8页
In this paper, the possible value of the differential uniformity of a function over finite fields is discussed. It is proved that, the differential uniformity of a function over Fq can be any even integer between 2 an... In this paper, the possible value of the differential uniformity of a function over finite fields is discussed. It is proved that, the differential uniformity of a function over Fq can be any even integer between 2 and q when q is even; and it can be any integer between 1 and q except q-1 when q is odd. Moreover, for any possible differential uniformity t, an explicit construction of a differentially t-uniform function is given. 展开更多
关键词 differential uniformity FUNCTIONS finite field explicit construction
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UNIFORMITIES ON COMPLETELY DISTRIBUTIVE LATTICES
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作者 梁基华 《Chinese Science Bulletin》 SCIE EI CAS 1990年第14期1162-1164,共3页
In order to study fuzzy topology and general topology in view of topological lattice, many researches have been carried out. Because of the lack of reverse order involution, there are some fundamental works, such as t... In order to study fuzzy topology and general topology in view of topological lattice, many researches have been carried out. Because of the lack of reverse order involution, there are some fundamental works, such as the theory of uniformity and metrization to be considered. In this note, we introduce the notion of uniformity on completely distributive lattice in terms of cover systems, and show that it is a good extension, we obtain some properties and prove that the equivalence of complete regularity and uniformizability on completely distributive lattices. 展开更多
关键词 TOPOLOGICAL MOLECULE LATTICE UNIFORMITY COMPLETE regularity.
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One-dimensional wave theory analysis of factors and characteristics influencing errors in two-wave method data processing in SHPB 被引量:1
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作者 Minghui Ma Guangfa Gao 《Acta Mechanica Sinica》 2025年第1期128-140,共13页
A simplified calculation of the specimen’s stress-strain curve is generally conducted using the two-wave method by the split Hopkinson pressure bar(SHPB),which aligns the onset of the transmitted and reflected waves.... A simplified calculation of the specimen’s stress-strain curve is generally conducted using the two-wave method by the split Hopkinson pressure bar(SHPB),which aligns the onset of the transmitted and reflected waves.However,this approach neglects the travel time of elastic waves within the specimen.Considering the travel time of elastic waves,this study quantitatively investigates the error characteristics and patterns of stress,strain,and strain rate in the specimen under different conditions using the theoretical two-wave method,and compares the results with those obtained using the onset-aligned twowave method.The study reveals that the stress-time curves derived from the theoretical two-wave method are lower than the actual stress curves,whereas those obtained from the onset-aligned two-wave method are consistently higher than the actual stress curves,with the stress deviation approximating a constant value when the dimensionless time exceeds 2.0.The starting point of the stress-strain curves obtained by the theoretical two-wave method is not zero but a point on the strain axis,whereas the onset-aligned two-wave method always starts at zero.However,the slopes of the stress-strain curves obtained by both methods differ from the actual Young’s modulus of the material,and functional relationships between the slopes and the actual Young’s modulus are provided.This research offers theoretical guidance for the refined design of SHPB experiments and the accurate processing of data. 展开更多
关键词 SHPB Stress wave effect Assumption of stress uniformity Dynamic stress-strain curve
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Cubature Kalman Fusion Filtering Under Amplify-and-Forward Relays With Randomly Varying Channel Parameters 被引量:1
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作者 Jiaxing Li Zidong Wang +2 位作者 Jun Hu Hongli Dong Hongjian Liu 《IEEE/CAA Journal of Automatica Sinica》 2025年第2期356-368,共13页
In this paper, the problem of cubature Kalman fusion filtering(CKFF) is addressed for multi-sensor systems under amplify-and-forward(AaF) relays. For the purpose of facilitating data transmission, AaF relays are utili... In this paper, the problem of cubature Kalman fusion filtering(CKFF) is addressed for multi-sensor systems under amplify-and-forward(AaF) relays. For the purpose of facilitating data transmission, AaF relays are utilized to regulate signal communication between sensors and filters. Here, the randomly varying channel parameters are represented by a set of stochastic variables whose occurring probabilities are permitted to exhibit bounded uncertainty. Employing the spherical-radial cubature principle, a local filter under AaF relays is initially constructed. This construction ensures and minimizes an upper bound of the filtering error covariance by designing an appropriate filter gain. Subsequently, the local filters are fused through the application of the covariance intersection fusion rule. Furthermore, the uniform boundedness of the filtering error covariance's upper bound is investigated through establishing certain sufficient conditions. The effectiveness of the proposed CKFF scheme is ultimately validated via a simulation experiment concentrating on a three-phase induction machine. 展开更多
关键词 Amplify-and-forward(AaF)relays covariance intersection fusion cubature Kalman filtering multi-sensor systems uniform boundedness
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THE SPECTRAL RADIUS OF UNIFORM HYPERGRAPH DETERMINED BY THE SIGNLESS LAPLACIAN MATRIX
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作者 HE Fang-guo 《数学杂志》 2025年第1期1-12,共12页
This paper studies the problem of the spectral radius of the uniform hypergraph determined by the signless Laplacian matrix.The upper bound of the spectral radius of a uniform hypergraph is obtained by using Rayleigh ... This paper studies the problem of the spectral radius of the uniform hypergraph determined by the signless Laplacian matrix.The upper bound of the spectral radius of a uniform hypergraph is obtained by using Rayleigh principle and the perturbation of the spectral radius under moving the edge operation,and the extremal hypergraphs are characterized for both supertree and unicyclic hypergraphs.The spectral radius of the graph is generalized. 展开更多
关键词 spectral radius uniform hypergraph Signless Laplasian matrix
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Optimizing neon-based gas mixtures for two-stage amplification fast-timing Micromegas detectors
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作者 Yue Meng Xu Wang +3 位作者 Jianbei Liu Ming Shao Zhiyong Zhang Yi Zhou 《中国科学技术大学学报》 北大核心 2025年第4期59-66,58,I0002,共10页
The PICOSEC Micromegas(MM)is a precise timing gaseous detector based on a Cherenkov radiator coupled with a semi-transparent photocathode and an MM amplifying structure.It features a two-stage amplification process th... The PICOSEC Micromegas(MM)is a precise timing gaseous detector based on a Cherenkov radiator coupled with a semi-transparent photocathode and an MM amplifying structure.It features a two-stage amplification process that leads to a significant deterioration of non-uniformity when scaling up to larger areas.Since the performance of gaseous detectors is highly dependent on the choice of working gas,optimizing the gas mixture offers a promising solution to improve the uniformity performance.This paper addresses these challenges through a combined approach of simulation based on Garfield++and experimental studies.The simulation investigates the properties of different mixing fractions of gas mixtures and their impact on detector performance,including gain uniformity and time resolution.To verify the simulation results,experimental tests were conducted using a multi-channel PICOSEC MM prototype with different gas mixtures.The experimental results are consistent with the findings of the simulation,indicating that a higher concentration of neon significantly improves the detector’s gain uniformity.Furthermore,the influence of gas mixtures on time resolution was explored as a critical performance indicator.The study presented in this paper offers valuable insights for improving uniformity in large-area PICOSEC MM detectors and optimizing overall performance. 展开更多
关键词 gaseous detectors MICROMEGAS timing detectors fast-timing Micromegas Monte Carlo simulation gain uniformity
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Research on the distance diversity of forest ecosystems based on the uniformity theory
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作者 Yeqiong Shi Chunling Lang Haifeng Qian 《Journal of Forestry Research》 2025年第6期147-156,共10页
Biodiversity has always been valued by ecology,Diversity is generally believed to lead to stability,and biodiversity is an important condition for ecosystems to maintain health.So what factors are related to forest ec... Biodiversity has always been valued by ecology,Diversity is generally believed to lead to stability,and biodiversity is an important condition for ecosystems to maintain health.So what factors are related to forest ecosystem biodiversity,and what kind of forest structure affects and determines the size of biodiversity.This study proposes the concept of contained uniformity based on the theory of uniformity,and uses the convergence of contained uniformity to obtain the judgment model of the forest station pattern type.At the same time,it proposes the concept of forest ecosystem distance diversity,and uses the judgment model of the stand pattern type to derive the mathematical definition of forest ecosystem distance diversity.Combining the ecological characteristics of different stand patterns and measurement indicators of forest ecosystem biodiversity,the connection between forest ecosystem distance diversity and biodiversity is derived,and this is used as an indicator to evaluate forest ecosystem biodiversity.Forest ecosystem distance diversity,as an indicator of biodiversity,can not only conduct early assessment and prediction of the biodiversity of immature forests(forests in the early succession or recovery stage),but also provide a quantitative basis for forest structure optimization.Ultimately realize the sustainable development of forestry production and operation and biodiversity protection. 展开更多
关键词 BIODIVERSITY UNIFORMITY Contained uniformity Distance diversity
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Polymer-assisted soybean crude urease carbonate precipitation technique for soil improvement
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作者 Zalfa Maulida Ihsani Naoki Kinoshita +1 位作者 Hideaki Yasuhara Heriansyah Putra 《Biogeotechnics》 2025年第4期27-42,共16页
This study presents a sustainable approach to soil improvement by integrating polyvinyl alcohol(PVA)into the Soybean Crude Urease Carbonate Precipitation(SCU-CP)technique.The research aims to enhance SCU-CP,which util... This study presents a sustainable approach to soil improvement by integrating polyvinyl alcohol(PVA)into the Soybean Crude Urease Carbonate Precipitation(SCU-CP)technique.The research aims to enhance SCU-CP,which utilizes soybean-derived urease to precipitate calcium carbonate,bonding soil particles and increasing strength.Challenges such as low solution viscosity and inconsistent carbonate precipitation are addressed by incorporating PVA,a biodegradable polymer that improves viscosity and retention.Comprehensive evaluations reveal significant findings:increasing PVA concentration enhances solution viscosity and results in higher calcium carbonate precipitation.Water retention assessments show that the PCP-1%treatment increases saturation water content(w_(s))to 0.263 compared to 0.217 for untreated soil,while also reduces the air-entry value(α).Unconfined Compressive Strength(UCS)tests indicate substantial improvement for PCP-1%,achieving approximately 140 kPa,with values reaching 179 kPa after 28 days.Calcium carbonate content measurements reveal that SCU-CP exhibits a variable distribution(standard deviation of 1.13),while PCP-1%demonstrates a more uniform distribution(standard deviation of 0.60),indicating improved effectiveness.Durability assessments through wet-dry cycling show that SCU-CP experiences a mass loss of 36.5%,while PCP-1%retains only 5%mass loss and maintains a UCS values.SEM images indicate that SCU-CP forms spherical structures,whereas PCP-1%produces a more diverse and crystalline morphology,suggesting better nucleation and distribution.Overall,the polymer-assisted SCU-CP technique(PCP)demonstrates significant potential for effective soil improvement. 展开更多
关键词 CARBONATES POLYMER Soil improvement UNIFORMITY
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My Views on School Uniforms
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作者 徐迪迪 《中学生英语》 2025年第18期6-6,共1页
At our school,we have to wear uniforms every day.The problem is that all my classmates think the uniforms are ugly.We think young people should look smart,because①we would like to wear our own clothes.Our teachers th... At our school,we have to wear uniforms every day.The problem is that all my classmates think the uniforms are ugly.We think young people should look smart,because①we would like to wear our own clothes.Our teachers think that if we do that,we will concentrate much②on our clothes than our studies.We don't agree. 展开更多
关键词 STUDIES school uniforms CLOTHING APPEARANCE
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Magnetron sputter and phase change optimization of waferlevel GeTe films for RF switch
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作者 Shihang Liu Hanxiang Jia +2 位作者 Shuangzan Lu Changyu Hu Jun Liu 《Journal of Semiconductors》 2025年第7期108-114,共7页
With the rapid advancement of 5G communication technology,increasingly stringent demands are placed on the performance and functionality of phase change switches.Given that RF and microwave signals exhibit characteris... With the rapid advancement of 5G communication technology,increasingly stringent demands are placed on the performance and functionality of phase change switches.Given that RF and microwave signals exhibit characteristics of high frequency,high speed,and high precision,it is imperative for phase change switches to possess fast,accurate,and reliable switching capabilities.Moreover,wafer-level compositional homogeneity and resistivity uniformity during semiconductor manufacturing are crucial for ensuring the yield and reliability of RF switches.By controlling magnetron sputter of GeTe through from four key parameters(pressure,power,Ar flow,and post-annealing)and incorporating elemental proportional compensation in the target,we achieved effective modulation over GeTe uniformity.Finally,we successfully demonstrated the process integration of GeTe phase-change RF switches on 6-inch scaled wafers. 展开更多
关键词 GETE magnetron sputter phase change in-wafer uniformity RF switch
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Impact of free electron laser coherence on imaging quality
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作者 Shuang Wei Shuang Gong +1 位作者 Yang Bu Zi-Jian Song 《Chinese Physics B》 2025年第5期385-397,共13页
The high temporal and spatial coherence of free electron lasers(FELs)reduces the uniformity of the illumination field,leading to scattering effects that blur the edges of patterns,resulting in diminished accuracy and ... The high temporal and spatial coherence of free electron lasers(FELs)reduces the uniformity of the illumination field,leading to scattering effects that blur the edges of patterns,resulting in diminished accuracy and clarity.Traditional imaging models regard the light source as fully incoherent,making it difficult to assess the impact of partially coherent light fields on imaging.If FELs are used in imaging systems,their coherence must be considered.To address this issue,this study explores the relationship between coherence,imaging quality and speckle contrast through a simulation method based on random phases.The method divides the light beam into temporal and spatial coherence cells,analyzes their interactions,and simulates imaging results under different coherence conditions.Additionally,speckle patterns for various illumination modes are calculated to evaluate their effects on speckle contrast and illumination uniformity.The results indicate that under different illumination modes,illumination uniformity decreases as coherence increases,while speckle contrast increases with higher coherence.In terms of imaging quality,higher coherence leads to an increase in both line edge roughness(LER)and line width roughness(LWR),thereby reducing the imaging quality.Additionally,the narrower the line width,the greater the impact of coherence on the imaging quality,resulting in poorer imaging performance. 展开更多
关键词 free electron laser COHERENCE IMAGING speckle contrast field uniformity
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Impacts of non-starch polysaccharide sources with enzymes influencing intestinal mucosa-associated microbiota and mucosal immunity of nursery pigs on growth and carcass traits at market weight
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作者 Jonathan T.Baker Zixiao Deng +1 位作者 Alexa R.Gormley Sung Woo Kim 《Journal of Animal Science and Biotechnology》 2025年第4期1595-1611,共17页
Background This study investigated the effects of different non-starch polysaccharide(NSP)sources with NSP degrading enzymes(NSPases)and the influence on the mucosa-associated microbiota and intestinal immunity of nur... Background This study investigated the effects of different non-starch polysaccharide(NSP)sources with NSP degrading enzymes(NSPases)and the influence on the mucosa-associated microbiota and intestinal immunity of nursery pigs,on growth performance and carcass traits at market weight.Methods One hundred and sixty newly weaned pigs at 7.0±0.3 kg body weight(BW)were allotted in a 2×2 factorial with NSP sources and NSPases serving as factors.The 4 dietary treatments were:DDGS,corn distillers'dried grains with solubles as source of NSP;DDGS+NSPases(DDGS+),DDGS with xylanase at 0.01%,3,000 U/kg of feed andβ-mannanase at 0.05%,400 U/kg of feed;SHWB,soybean hulls and wheat bran replacing corn DDGS as the source of NSP;SHWB with NSPases(SHWB+),SHWB with xylanase at 0.01%,3,000 U/kg of feed andβ-mannanase at 0.05%,400 U/kg of feed.Pigs were fed for 37 d and housed in groups of 4 pigs per pen.At d 37,the median body weight pig in each pen was euthanized for sampling to analyze intestinal health parameters.Remaining pigs were fed a common diet for subsequent phases to evaluate the carryover effect on growth and carcass traits.Results The SHWB decreased(P<0.05)the relative abundance of Helicobacter,tended to increase(P=0.074)the relative abundance of Lactobacillus,increased(P<0.05)immunoglobulin G(IgG)in the jejunal mucosa,tended to increase(P=0.096)the villus height(VH)in the jejunum,and tended to improve ADG(P=0.099)and feed efficiency(P=0.068)during phase 1 compared to DDGS treatment.Supplementation of NSPases increased(P<0.05)Shannon index of diversity,increased the relative abundance of Streptococcus and Acinetobacter,and tended to increase(P=0.082)dry matter digestibility.The BW of pigs fed SHWB was more uniform(P<0.05)at the end of the 120 d study.Additionally,hot carcass weight of pigs fed SHWB tended to be more uniform(P=0.089)than DDGS treatment.Conclusion Soybean hulls and wheat bran replacing DDGS in nursery diets improved uniformity of pigs at market weight,which might be attributed to beneficial modulation of the mucosa-associated microbiota and enhanced intestinal morphology during the nursery phase.Supplementation of NSPases had beneficial effects on the intestinal mucosa-associated microbiota,digestibility,and intestinal immunity in SHWB treatment,whereas no carryover effects were overserved at market weight. 展开更多
关键词 Intestinal health Mucosa-associated microbiota Non-starch polysaccharides Nursery pigs UNIFORMITY
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