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Nonlinear mechanical analysis of load-bearing characteristics of coal-support-backfill system crossing abandoned roadways
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作者 Jun Guo Zi Wang +8 位作者 Guorui Feng Jinwen Bai Xiaoze Wen Wenbo Huang Jie Zhang Wenming Feng Quan Liu Jiahao Zhang Longlong Yang 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期246-264,共19页
Roof pre-fracture poses a considerable risk during the re-mining of residual coal above abandoned roadways,threatening the safety of the mining faces.This study employs a Winkler foundation beam model for mechanical a... Roof pre-fracture poses a considerable risk during the re-mining of residual coal above abandoned roadways,threatening the safety of the mining faces.This study employs a Winkler foundation beam model for mechanical analysis of roof structures and adopts a multivariate nonlinear analysis approach to explore the synergistic load-bearing effects within the'coal pillar-support-backfill body'system during the fill and re-mining processes above these roadways.The findings demonstrate that backfill mining significantly reduces stress concentrations in coal pillars and reduces excessive bending moments in roofs near abandoned roadways.The roof deflection equation incorporates three critical factors affecting stability during backfill mining:the width of the coal pillar(L_(3)),the working resistance of the support(q_(z)),and the elastic foundation coefficient of the backfill material(kcÞ.Under single-factor conditions,the impact sequence on roof stability in the coal pillar zone is·k_(c)>L_(3)>q_(z).Further,multivariate nonlinear analysis reveals the interactions within the'coal-support-backfill'structure,indicating that in terms of roof control,the interaction terms are ordered as L_(3)·k_(c)>q_(z)·k_(c)>L_(3)q_(z).Therefore,priority should be given to adjusting the coal pillar width and backfill strength,followed by modifications to the support resistance and backfill strength during the recovery of abandoned roadways.An improved understanding of these interactions will help optimize strategies for the recovery of residual coal through abandoned roadways,thereby enhancing the stability and safety of mining operations under complex geological conditions. 展开更多
关键词 Filling re-mining Coal pillar instability Abandoned roadway crossing Similar simulation Synergistic load-bearing
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The Crossing Number of Two Classes of Join Graphs
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作者 LU Shengxiang WANG Shu WANG Jing 《数学进展》 北大核心 2025年第5期983-991,共9页
Determining the crossing number of a given graph is NP-complete. The cycle of length m is denoted by Cm = v1v2…vmv1. G^((1))_(m) (m ≥ 5) is the graph obtained from Cm by adding two edges v1v3 and vlvl+2 (3 ≤ l ≤ m... Determining the crossing number of a given graph is NP-complete. The cycle of length m is denoted by Cm = v1v2…vmv1. G^((1))_(m) (m ≥ 5) is the graph obtained from Cm by adding two edges v1v3 and vlvl+2 (3 ≤ l ≤ m−2), G^((2))m (m ≥ 4) is the graph obtained from Cm by adding two edges v1v3 and v2v4. The famous Zarankiewicz’s conjecture on the crossing number of the complete bipartite graph Km,n states that cr(Km,n)=Z(m,n)=[m/2][m-1/2][n/2[n-1/2].Based on Zarankiewicz’s conjecture, a natural problem is to study the change in the crossingnumber of the graphs obtained from the complete bipartite graph by adding certain edge sets.If Zarankiewicz’s conjecture is true, this paper proves that cr(G^((1))_(m)+Kn)=Z(m,n)+2[n/2] and cr(G^((2))_(m)+Kn)=Z(m,n)+n. 展开更多
关键词 crossing number DRAWING join graph
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Dynamic response and wear analysis of a swing nose crossing in heavy haul railways
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作者 Enhui Zhang Chung Lun Pun +1 位作者 Alvin Hiew Wenyi Yan 《Railway Engineering Science》 2025年第2期192-215,共24页
Swing nose crossings(SNXs)have been widely used in heavy haul railways to create a smoother load transfer and hence reduced impact load.However,the current design of SNXs hasn’t been fully examined under heavy haul o... Swing nose crossings(SNXs)have been widely used in heavy haul railways to create a smoother load transfer and hence reduced impact load.However,the current design of SNXs hasn’t been fully examined under heavy haul operating conditions.Additionally,maintenance guidelines for SNX wear-related issues in Australian heavy haul railways are relatively lacking.As such,this study aims to investigate the dynamic response of the wheel-rail contact and analyse the wear performance of an SNX currently used in Australian heavy haul railways.Dynamic implicit-explicit finite element analysis was conducted to simulate the wheel-rail contact along the SNX.The distribution of the wear intensity over the SNX was identified by using a local contact-based wear model.The influence of various scenarios on wear was also explored.The results verify the improved dynamic performance of the SNX,as the increased contact force after load transfer remains below 1.2 times the static load.The findings also indicate that the decrease in relative height and increase in nose rail inclination result in greater wear on the nose rail.Notably,the SNX considered in the current study exhibits better wear performance when used with moderately worn wheels. 展开更多
关键词 WEAR Heavy haul railways Swing nose crossing Finite element method Wheel-rail contact
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Face-to-face π-π interactions and electron communication boosting efficient reverse intersystem crossing in through-space charge transfer molecules
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作者 Manlin Lu Sheng Liao +6 位作者 Jiayu Li Zidong Yu Ningjiu Zhao Zuoti Xie Shunli Chen Li Dang Ming-De Li 《Chinese Chemical Letters》 2025年第6期764-771,共8页
The excited state dynamics and critically regulated factors of reverse intersystem crossing(RISC)in through-space charge transfer(TSCT)molecules have received insufficient attention.Here,five molecules of through spac... The excited state dynamics and critically regulated factors of reverse intersystem crossing(RISC)in through-space charge transfer(TSCT)molecules have received insufficient attention.Here,five molecules of through space/bond charge transfer inducing thermally activated delayed fluorescence(TADF)are prepared,and their excited state charge transfer processes are studied by ultrafast transient absorption and theoretical calculations.DM-Z has a largerΔEST,leading to a longer lifetime of intersystem crossing(ISC),resulting in the lowest photoluminescence quantum yield(PLQY).Oppositely,ISC and RISC are demonstrated to take place with shorter lifetimes for TSCT molecules.The face-to-faceπ-πstacking interactions and electron communication enable DM-B and DM-BX to have an efficient RISC,increasing the weight coefficient of RISC from 1.7%(DM-X)to close to 50%(DM-B and DM-BX)in the solvents,which make DM-BX and DM-B to have a high PLQY.However,partial local excitation in the donor center is observed and the charge transfer is decreased for DM-G and DM-X.The triplet excited state(DM-G)or singlet excited state(DM-X)mainly undergoes inactivation through a non-radiative relaxation process,resulting in less RISC and low PLQY.This work provides theoretical hints to enhance the RISC process in the TADF materials. 展开更多
关键词 Through-space charge transfer Reverse intersystem crossing Thermally activated delayed fluorescence Transient absorption Through-bond charge transfer
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Enhancing faba bean breeding efficiency through insect pollination and smart crossing schemes
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作者 Rica-Hanna Schlichtermann Charlotte Häuser +6 位作者 Sven EWeber Lennart Scheer Hanna Tietgen Gregor Welna Sarah V.Schiessl Benjamin Wittkop Rod J.Snowdon 《The Crop Journal》 2025年第6期1816-1826,共11页
Faba bean,with its high protein yield and low nitrogen inputs,is a promising crop,but it suffers from low yield stability due to poor heat and drought adaptation.To improve yield performance,faba beans can be produced... Faba bean,with its high protein yield and low nitrogen inputs,is a promising crop,but it suffers from low yield stability due to poor heat and drought adaptation.To improve yield performance,faba beans can be produced as synthetic cultivars,where multiple lines are advanced through open pollination resulting in offsprings,which are a mixture of F_(1)-hybrids and self-pollinated offsprings.This leads to an enhanced performance due to per se performance of the components and heterotic effects of F_(1)-hybrids.While distinct genetic pools have shown high heterotic effects in hybrid breeding programs,they have not been systematically established in faba bean breeding.To promote establishment of heterotic pools,we employed a cost-effective chain-crossing scheme accompanied with only 58 genome-wide KASP-markers and generated diverse genetically distinct pools within one generation.However,artificial crossing methods in faba bean result in low crossing efficiency and seed set.To overcome this,we introduced bumblebee-assisted intercrossing in greenhouse chambers,achieving an increased seed set and further enhancing genetic distance between gene pools.Genotyping was conducted with an Illumina 10K SNP-chip,which enabled the identification of F_(1)×F_(1) double-cross combinations and F2 self-pollinated offsprings from open pollinated offsprings with a custom pipeline.In contrast to standard crossing and recombinant inbred line(RIL)production in faba bean,which results in small families with limited recombination,the chain-crossing scheme and within-pool open pollination allows us to rapidly generate large and diverse base populations for future breeding,genetic studies and with that to increase genetic gain in faba bean. 展开更多
关键词 Vicia faba Heterotic groups Hybrid breeding Population development Cross efficiency Open pollination
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Electrospinning of FeNiCo/carbon nanofibers:a new paradigm for lightweight microwave absorbers
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作者 Yuan Wenpei Qu Lin +3 位作者 Wang Yajing Liu Pengyu Zhang Yanlan Wang Yongzhen 《新型炭材料(中英文)》 北大核心 2026年第1期234-252,共19页
With the rapid development of modern electronic technology,the demand for high-performance microwave absorption materials has increased dramatically.In order to meet this demand,the electrospinning of FeNiCo/carbon na... With the rapid development of modern electronic technology,the demand for high-performance microwave absorption materials has increased dramatically.In order to meet this demand,the electrospinning of FeNiCo/carbon nanofiber(FeNiCo/CNF)composites with excellent microwave absorption properties was developed,and their potential as high frequency microwave absorption materials was evaluated.Experiment showed that FeNiCo/CNFs achieve a minimum reflection loss(RL_(min))of−55.5 dB with a matching thickness of only 1.6 mm.Microstructure analysis and electromagnetic parameter testing showed that the excellent microwave absorbing properties were mainly due to the combined effect of the network structure of carbon nanofibers and the FeNiCo alloy.This interaction promotes multiple reflections and the efficient absorption of microwaves.Computer simulation also showed that the FeNiCo/CNF composites produce an excellent radar cross-section reduction in typical radar operating frequency bands,which validates their potential application in stealth technology.This is a new concept in the development of high-performance microwave absorption materials. 展开更多
关键词 ELECTROSPINNING ALLOY Composite nanofibers Radar cross section Microwave absorption
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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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Exploring the industrial potential of Moroccan oat varieties for functional food applications
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作者 Salma Touil Aouatif Benali +2 位作者 Ahmed Douaik Nadia Belahbib Nezha Saidi 《Grain & Oil Science and Technology》 2026年第1期42-52,共11页
Morocco's oat sector is shifting from forage to food,creating demand for varieties with proven processing performance.We profiled nine Moroccan oats(four parental lines,four interspecific derivatives,and one hull-... Morocco's oat sector is shifting from forage to food,creating demand for varieties with proven processing performance.We profiled nine Moroccan oats(four parental lines,four interspecific derivatives,and one hull-less diploid check)against the key drivers of functionality:β-glucan,hydration metrics(WAI,WSI,swelling power),interfacial metrics(foam capacity/stability,emulsion capacity/stability),and kernel geometry(thousand-kernel weight/width),using SEM to interpret microstructure.Varietal differences were pronounced and actionable.The A.sativa×A.magna derivative Hamdali showed fast wetting(low WAI),strong foaming(highest FS),and high emulsion capacity.These traits make it suitable for oat drinks and large,crack-free flakes.The A.sativa×A.murphyi descendants Al Fawze and Abtah exhibited restrained swelling(lower SP)and moderate WAI/WSI,favoring crisp snacks,biscuits,and pasta;Abtah additionally delivered high emulsion stability suitable for shelf-stable beverages.Amlal and Nezha offered balanced,steerable profiles.Linkingβ-glucan,hydration,and interfacial behavior to kernel traits provides a variety-to-application map for Moroccan oats.We recommend Hamdali/Niema for foamed beverages/flakes;Tissir/Soualem for porridges and thick beverages;Abtah for pasta and stable emulsions;Al Fawze for crisp snacks/biscuits. 展开更多
关键词 Moroccan oat cultivars Techno-functional traits Functional food applications Grain microstructure Interspecific crosses
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Radiative Features of Darcy Forchheimer Flow of Entropy-Optimized Cross Flow Conveying Ternary Hybrid Nanofluid Past a Stretching Cylinder
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作者 M.Faizan Syed Sohaib Zafar +3 位作者 Farhan Ali Umair Khan Aurang Zaib Najiyah Safwa Khashi’ie 《Frontiers in Heat and Mass Transfer》 2026年第1期97-119,共23页
The purpose of the present investigation is to explore the implications of Cross fluid in a Darcy-Forchheimer porousmediumdue to the tri-hybrid nanofluid past a porous cylinder.Thermal radiation,heat generation,therma... The purpose of the present investigation is to explore the implications of Cross fluid in a Darcy-Forchheimer porousmediumdue to the tri-hybrid nanofluid past a porous cylinder.Thermal radiation,heat generation,thermal convection,solutal convective and chemical reaction have been encountered in this analysis.Entropy generation has been accounted for under the fluidic friction,heat rate analysis,and porosity analysis.Three different nanoparticles of multiwall carbon nanotube(MWCNT),aluminum oxide(Al_(2)O_(3)),and silver(Ag)are utilized to illustrate the tri-hybrid nanofluid flow with Ethlene Glycol(EG)as the base fluid.The governance model,consisting of linked inadequate differential conditions,is transformed into an ordinary configuration of nonlinear coupled differential conditions by acceptable adjustments.The obtained outcomes in combination with the bvp4c approach are then used to resolve the generated ODEs.For discussion purposes,the impacts of the physical limitations on temperature profile,velocity,and concentration have also been illustrated.Numerical results have been obtained for the diffusion rate,heat transfer rate,drag force,and other factors.While the Forchheimer parameter and the inclination angle reduce the fluid flow’s velocity,the Biot number of heat and mass transfer influences the fluid’s temperature.According to the findings,hybrid nanofluid is the most effective way to improve heat transmission and may also be utilized for cooling.Three different kinds of nanofluids were used in a comparative examination to clarify the study’s conclusions.Changes in viscosity and porousness caused the nanofluids’velocity to drop by 13.12%and 15.8%,respectively;however,trihybrid nanofluids with improved convection showed a 13.12%rise. 展开更多
关键词 Stretching cylinder tri-hybrid nanofluid thermal radiation cross fluid heat source/sink
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Texture traits and mechanical anisotropy of AZ31 magnesium alloy sheet by hard plate cross rolling
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作者 Jia Yang Zhang Feng Li +2 位作者 Lu Sun Wen Tao Niu Mu Zi Cao 《Journal of Magnesium and Alloys》 2026年第1期550-564,共15页
Conventional cross rolling is influenced by the force couple effect of symmetrical rollers,resulting in the c-axis of the plate grains being oriented perpendicular to the rolling surface.This orientation contributes t... Conventional cross rolling is influenced by the force couple effect of symmetrical rollers,resulting in the c-axis of the plate grains being oriented perpendicular to the rolling surface.This orientation contributes to a high degree of work hardening and mechanical anisotropy,thereby complicating subsequent processing.In this study,the hard plate cross rolling(HP-CR)process is put forward for the first time,and the microstructure evolution and mechanical properties of rolled AZ31 Magnesium plate were analyzed.The results indicate that,in comparison to traditional cross rolling(CR),the average grain size of the HP-CR is refined to 5.33µm.Additionally,the average yield strength and elongation of the sheet are enhanced by 15.2%and 35.2%,respectively,while the average tensile strength is 283 MPa,and the r value decreases by 39.8%.These changes are attributed to the combined effects of grain refinement,microstructural homogenization,and basal texture weakening.On the one hand,the substantial energy stored in the original lattice distortion serves as a driving force for the dynamic recrystallization process,facilitating the elimination of the deformed grain structure.This process increases the proportion of recrystallized grains from 5%to 82%,reduces the degree of work hardening,and correspondingly decreases the density of geometrically necessary dislocations(ρ^(GND))by 70.8%,accompanied by the formation of high-angle grain boundaries(HAGB).On the other hand,dynamic recrystallization promotes grain rearrangement,resulting in an increased number of grains oriented in the transverse direction(TD),which diminishes the texture strength of the basal plane.Concurrently,the activation of non-basal slip systems reduces the resistance to dislocation sliding in various directions,significantly reduces the degree of mechanical anisotropy and enhancing the plastic deformation capacity of the plate.This research provides valuable scientific insights and technical foundations for the large-scale manufacturing of high-performance AZ31 magnesium alloy sheets. 展开更多
关键词 Hard plate cross rolling Magnesium alloy sheet Texture evolution Mechanical anisotropy
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Investigation of the production of ^(152)Tb and ^(155)Tb terbium radioisotopes with europium targets
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作者 C.Yalçın 《Nuclear Science and Techniques》 2026年第2期183-193,共11页
In recent years,terbium radioisotopes have been investigated for their potential therapeutic and diagnostic applications in nuclear medicine.This study aimed to investigate the production of ^(152) Tb and ^(155) Tb by... In recent years,terbium radioisotopes have been investigated for their potential therapeutic and diagnostic applications in nuclear medicine.This study aimed to investigate the production of ^(152) Tb and ^(155) Tb by alpha-induced reactions in detail,with a specific focus on determining the optimum production parameters and testing existing nuclear models.Given the limited number of experiments conducted on reactions related to terbium isotope production,it is necessary to perform theoretical calculations of cross sections over a wide energy range to gain a detailed understanding of terbium isotope production.To achieve this objective,the cross sections of the ^(151)Eu(α,n)^(154) Tb reactions were calculated up to 60 MeV using the TALYS computer code with 432 different combinations of optical model parameters,level density,and strength function models.The theoretical reaction cross-section results were compared with the experimental results in the literature.The best input parameters were determined using the Threshold Logic Unit method,and these parameters were used in all isotope production calculations.Once the optimal model combination was determined,the total activity production and isotopic fraction of ^(152) Tb and ^(155) Tb isotopes were calculated in detail for beam energies of 17–50 MeV,different irradiation times,and varying ^(151) Eu and ^(153) Eu target thicknesses. 展开更多
关键词 Terbium radioisotopes Medical isotope production Alpha-induced reactions Cross section Threshold logic unit method
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CDA-Net:Cross dimensional attention network for wetland bird detection
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作者 Jia'nan Lv Changchun Zhang +1 位作者 Jiangjian Xie Junguo Zhang 《Avian Research》 2026年第1期216-227,共12页
Monitoring waterbirds is vital for evaluating the ecological health of wetlands,and object detection offers an automated solution for identifying birds in monitoring imagery.However,conventional detection methods ofte... Monitoring waterbirds is vital for evaluating the ecological health of wetlands,and object detection offers an automated solution for identifying birds in monitoring imagery.However,conventional detection methods often overlook the multi-scale nature of bird targets,limiting their ability to capture rich contextual information across different scales.To address this,we propose a cross-dimensional attention network(CDA-Net)for bird detection that integrates spatial and channel information to improve species recognition.The proposed CDA-Net partitions feature maps into multiple channel wise sub-features.Spatial and channel attention are applied to each subfeature,and the resulting features are fused using the Hadamard product.The fused features are then forwarded to the detection head to generate the final detection results.This approach effectively captures and integrates information across spatial and channel dimensions.Experiments on our self-constructed Nanhai Wetland Waterbird Dataset and the public CUB-200-2011 dataset yield precision scores of 91.32%and 81.99%,respectively,outperforming existing methods.Our approach effectively handles scale variation in bird detection and provides a valuable tool for advancing automated wetland waterbird monitoring. 展开更多
关键词 Bird detection Channel and spatial attention Cross dimensional network Feature integration Multi sizes object
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Production of proton-rich isotopes of Pu,Cm,Bk,Ds,Cn,Fl by fusion evaporation reactions with^(40)Ar projectile
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作者 Qing-Qing Yao Tian-Liang Zhao Xiao-Jun Bao 《Nuclear Science and Techniques》 2026年第3期119-131,共13页
The evaporation residual cross sections(ERCSs)of these reactions were calculated by using^(144)Sm,^(160,164)Dy,^(165)Ho,^(166)Er,^(169)Tm,^(171,174)Yb,^(175)Lu,^(176-180)Hf,^(181)Ta,^(180,182)W and^(187)Re targets wit... The evaporation residual cross sections(ERCSs)of these reactions were calculated by using^(144)Sm,^(160,164)Dy,^(165)Ho,^(166)Er,^(169)Tm,^(171,174)Yb,^(175)Lu,^(176-180)Hf,^(181)Ta,^(180,182)W and^(187)Re targets with^(40)Ar projectiles in the theoretical framework of the dinuclear system(DNS)model.The de-excitation process of the compound nucleus was theoretically calculated using two different statistical models,namely the statistical model 1 and statistical model 2(GEMINI++model).The calculated ERCSs were also compared with the experimental data.The ERCSs of synthesizing new proton-rich nuclides were investigated based on the fusion evaporation reaction.Predictions were made for the ERCSs of new isotopes of Pu,Cm and Bk in the heavy nuclei region,while the new isotopes of Ds,Cn and Fl are predicted in the superheavy nuclei region of Z≥104. 展开更多
关键词 Dinuclear system model Evaporation residue cross section Proton-rich nuclides
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Generalized reduced R-matrix theoretical analysis of the^(5)He system
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作者 Xu Han Tao Ye +4 位作者 Zhen-Peng Chen Hai-Rui Guo Wei-Li Sun Zhi-Hao Sun Hao-Yang Fan 《Nuclear Science and Techniques》 2026年第4期188-201,共14页
Based on the generalized reduced R-matrix theory,the R-matrix analysis code(RAC program)was used to analyze the experimental data of all the nuclear reaction channels related to the 5 He system.The current calculation... Based on the generalized reduced R-matrix theory,the R-matrix analysis code(RAC program)was used to analyze the experimental data of all the nuclear reaction channels related to the 5 He system.The current calculations provide accurate and reliable evaluation data and are in good agreement with the experimental data.In this study,self-consistent evaluation data for each reaction were obtained using multi-channel and multi-energy fitting.In particular,the error propagation theory of generalized least squares was used to determine the error of the evaluation data and the covariance matrix of the integral cross section.This R-matrix analysis for the 5 He system has three features.First,for the first time,the error in the evaluation data of the T(d,n)^(4)He reaction cross section and the covariance matrix of the integral cross section are provided.Second,we used only one set of R-matrix parameters to depict the reaction cross section of each reaction channel of the 5 He system for the entire energy region in our work.Third,in this evaluation,we considered some of the latest measured experimental data,especially after 2000.The T(d,n)^(4)He reaction cross section at 0.1 MeV and below was carefully studied.The effect of different energy levels in T(d,n)^(4)He was analyzed,with the energy levels 3/2^(+)making a major contribution to the cross section,and the role of the S-wave and P-wave from 3/2~-determines the lean forward trend of the angular distributions at 0.01–0.1 MeV. 展开更多
关键词 R-matrix theory Nuclear reaction cross section Evaluation of data Generalized least squares ^(5)He system
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Effect of different artificial aging treatments on tensile creep behavior of extruded lean Mg−Al−Ca−Mn alloy
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作者 Ming-yu LI Zhi-ping GUAN +6 位作者 Jia-wang SONG Hong-jie JIA Pin-kui MA Gang WANG Wei YAN Ming-hui WANG Zhi-gang LI 《Transactions of Nonferrous Metals Society of China》 2026年第1期112-123,共12页
The effects of artificial aging(T6)on the creep resistance with tensile stresses in the range of 50−80 MPa at 175℃were investigated for an extruded Mg−1.22Al−0.31Ca−0.44Mn(wt.%)alloy.The Guinier-Preston(G.P.)zones pr... The effects of artificial aging(T6)on the creep resistance with tensile stresses in the range of 50−80 MPa at 175℃were investigated for an extruded Mg−1.22Al−0.31Ca−0.44Mn(wt.%)alloy.The Guinier-Preston(G.P.)zones primarily precipitate in the sample aged at 200℃for 1 h(T6-200℃/1h),while the Al_(2)Ca phases mainly precipitate in the sample aged at 275℃for 8 h(T6-275℃/8h).The T6-200℃/1h sample exhibits excellent creep resistance,with a steady-state creep rate one order of magnitude lower than that of the T6-275℃/8h sample.The abnormally high stress exponent(~8.2)observed in the T6-200℃/1h sample is associated with the power-law breakdown mechanism.TEM analysis illuminates that the creep mechanism for the T6-200℃/1h sample is cross-slip between basal and prismatic dislocations,while the T6-275℃/8h sample exhibits a mixed mechanism of dislocation cross-slip and climb.Compared with the Al_(2)Ca phase,the dense G.P.zones effectively impede dislocation climb and glide during the creep process,demonstrating superior creep resistance of the T6-200℃/1h sample. 展开更多
关键词 Mg−Al−Ca−Mn alloy tensile creep artificial aging cross slip
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IL-17 as a New Player in Neuroimmune Cross-Talk:Rewiring Behaviors Through Cytokine-Receptor Cartography
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作者 Jinmei Ye Lan Yan +4 位作者 Zhibo Tang Jiashuo Xu Jie Weng Tifei Yuan Daihui Peng 《Neuroscience Bulletin》 2026年第2期476-480,共5页
In recent years,the field of neuroimmunology has witnessed a profound paradigm shift.Research has expanded beyond the traditional focus on the central nervous system to unravel the dynamic interplay between peripheral... In recent years,the field of neuroimmunology has witnessed a profound paradigm shift.Research has expanded beyond the traditional focus on the central nervous system to unravel the dynamic interplay between peripheral immunity and neural networks.Cutting-edge methodologies have unmasked a tripartite communication axis enabling peripheral immune signals to mediate the CNS:(1)neural communication via vagal afferents,(2)humoral signaling through circumventricular organ cytokine diffusion,and(3)cellular interactions involving bone marrow-derived macrophages[1]. 展开更多
关键词 NEUROIMMUNOLOGY IL vagal afferents circumventricular organ cytokine diffusionand cellular interacti cytokine receptor cartography neuroimmune cross talk vagal afferents humoral central nervous system
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KPA-ViT:Key Part-Level Attention Vision Transformer for Foreign Body Classification on Coal Conveyor Belt
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作者 Haoxuanye Ji Zhiliang Chen +3 位作者 Pengfei Jiang Ziyue Wang Ting Yu Wei Zhang 《Computers, Materials & Continua》 2026年第3期656-671,共16页
Foreign body classification on coal conveyor belts is a critical component of intelligent coal mining systems.Previous approaches have primarily utilized convolutional neural networks(CNNs)to effectively integrate spa... Foreign body classification on coal conveyor belts is a critical component of intelligent coal mining systems.Previous approaches have primarily utilized convolutional neural networks(CNNs)to effectively integrate spatial and semantic information.However,the performance of CNN-based methods remains limited in classification accuracy,primarily due to insufficient exploration of local image characteristics.Unlike CNNs,Vision Transformer(ViT)captures discriminative features by modeling relationships between local image patches.However,such methods typically require a large number of training samples to perform effectively.In the context of foreign body classification on coal conveyor belts,the limited availability of training samples hinders the full exploitation of Vision Transformer’s(ViT)capabilities.To address this issue,we propose an efficient approach,termed Key Part-level Attention Vision Transformer(KPA-ViT),which incorporates key local information into the transformer architecture to enrich the training information.It comprises three main components:a key-point detection module,a key local mining module,and an attention module.To extract key local regions,a key-point detection strategy is first employed to identify the positions of key points.Subsequently,the key local mining module extracts the relevant local features based on these detected points.Finally,an attention module composed of self-attention and cross-attention blocks is introduced to integrate global and key part-level information,thereby enhancing the model’s ability to learn discriminative features.Compared to recent transformer-based frameworks—such as ViT,Swin-Transformer,and EfficientViT—the proposed KPA-ViT achieves performance improvements of 9.3%,6.6%,and 2.8%,respectively,on the CUMT-BelT dataset,demonstrating its effectiveness. 展开更多
关键词 Foreign body classification global and part-level key information coal conveyor belt vision transformer(ViT) self and cross attention
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Single electron capture in low-and intermediate-energy collisions of Si^(3,4+)with He
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作者 Yingzhou Li Yadong Liu +3 位作者 Yueying Qi Ling Liu Yizhi Qu Jianguo Wang 《Chinese Physics B》 2026年第1期150-157,共8页
The single electron capture processes in Si^(3,4+)+He collisions have been investigated theoretically employing the two-center atomic orbital close-coupling method in the energy range 0.01-100 keV/u.Total and state-se... The single electron capture processes in Si^(3,4+)+He collisions have been investigated theoretically employing the two-center atomic orbital close-coupling method in the energy range 0.01-100 keV/u.Total and state-selective electron capture cross sections for the dominant and subdominant reaction channels are calculated and compared with the available experimental and theoretical data.For the total charge transfer cross sections,the present results show better agreements with the available experimental data than the other theoretical ones in the overlapping energy region for both collision systems.For the state-selective cross sections,the present results for 3s and 3p states are in general agreement with the previous MOCC results in the low energy region for both collision systems.Furthermore,the cross sections for electron captured to the 3d,4l and 5l(l=0,1,...,n-1)states of Si^(2+)and Si^(3+)ions are first provided in a broad energy region in our work.These results are useful for the investigations in astrophysics.The datasets presented in this paper,including the total and state-selective electron capture cross sections of Si^(3,4+)+He collisions in 0.01-100 ke V/u,are openly available at https://doi.org/10.57760/sciencedb.j00113.00257. 展开更多
关键词 atomic orbital close-coupling single electron capture cross section
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A Cross-Band Quantum Light Source Based on Spontaneous Four-Wave Mixing in a Shallow-Ridge Silicon Waveguide
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作者 Yijia Wang Qirui Ren +2 位作者 Zhanping Jin Yidong Huang Wei Zhang 《Chinese Physics Letters》 2026年第1期64-70,共7页
To fully utilize the resources provided by optical fiber networks,a cross-band quantum light source generating photon pairs,where one photon in a pair is at C band and the other is at O band,is proposed in this work.T... To fully utilize the resources provided by optical fiber networks,a cross-band quantum light source generating photon pairs,where one photon in a pair is at C band and the other is at O band,is proposed in this work.This source is based on spontaneous four-wave mixing(SFWM)in a piece of shallow-ridge silicon waveguide.Theoretical analysis shows that the waveguide dispersion could be tailored by adjusting the ridge width,enabling broadband photon pair generation by SFWM across C band and O band.The spontaneous Raman scattering(SpRS)in silicon waveguides is also investigated experimentally.It shows that there are two regions in the spectrum of generated photons from SpRS,which could be used to achieve cross-band photon pair generation.A chip of shallow-ridge silicon waveguide samples with different ridge widths has been fabricated,through which cross-band photon pair generation is demonstrated experimentally.The experimental results show that the source can be achieved using dispersion-optimized shallow-ridge silicon waveguides.This cross-band quantum light source provides a way to develop new fiber-based quantum communication functions utilizing both C band and O band and extends applications of quantum networks. 展开更多
关键词 photon pair generation shallow ridge silicon waveguide spontaneous four wave mixing optical fiber networks adjusting ridge widthenabling cross band quantum light source broadband photon pair generation waveguide dispersion
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Neo-translation,Appreciation and Analysis of Tennyson's Crossing the Bar
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作者 李绍青 《海外英语》 2011年第9X期223-224,共2页
As a world-widely popular poem,Tennyson's Crossing the Bar attracts more and more people to cherish it.And this paper aims at translating it in a new way,and analyzing it in a fully scientific way.
关键词 TENNYSON crossing the BAR new TRANSLATION APPRECIATION ANALYSIS
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