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Benchmark experiment system for^(252)Cf spontaneous fission source usingγtagging
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作者 Yu-Ting Wei Chang-Lin Lan +11 位作者 Bo Gao Xian-Lin Yang Gong Jiang Jia-Hao Wang Bo Xie Yang-Bo Nie Yan-Liang Chang Ge Zhang Fan Wu Kuo-Zhi Xu Shi-Long Liu Xi-Chao Ruan 《Nuclear Science and Techniques》 2025年第11期221-231,共11页
Benchmark experiments are indispensable for the development of neutron nuclear data evaluation libraries.Given the lack of domestic benchmarking of nuclear data in the fission energy region,this study developed a neut... Benchmark experiments are indispensable for the development of neutron nuclear data evaluation libraries.Given the lack of domestic benchmarking of nuclear data in the fission energy region,this study developed a neutron leakage spectrum measurement system using a spherical sample based on the^(252)Cf spontaneous fission source.The EJ309 detector(for highenergy measurements)and CLYC detector(for low-energy measurements)were combined to measure the time-of-flight spectrum using theγtagging method.To assess the performance of the system,the time-of-flight spectrum without a sample was measured first.The experimental spectra were consistent with those simulated using the Monte Carlo method and the standard^(252)Cf spectrum from ISO:8529-1.This demonstrates that the system can effectively measure the neutron events in the 0.15-8.0 MeV range.Then,a spherical polyethylene sample was used as the standard to verify the accuracy of the system for the benchmark experiment.The simulation results were obtained using the Monte Carlo method with evaluated data from the ENDF/B-Ⅷ.0,CENDL-3.2,JEFF-3.3,and JENDL-5 libraries.The measured neutron leakage spectra were compared with the corresponding simulated results for the neutron spectrum shape and calculated C/E values.The results showed that the simulated spectra with different data libraries reproduced the experimental results well in the 0.15-8.0 MeV range.This study confirms that the leakage neutron spectrum measurement system based on the^(252)Cf source can perform benchmarking and provides a foundation for evaluating neutron nuclear data through benchmark experiments. 展开更多
关键词 ^(252)Cf Neutron leakage spectrum Benchmark experiment Time-of-flight technique Evaluated nuclear data Spherical samples
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Development of an Intelligent Vehicle Experiment System 被引量:5
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作者 YANG Xinhong GAO Feng +2 位作者 LIU Guoliang WANG Guofu XU Guoyan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2010年第6期684-689,共6页
Existing vehicle experiment systems tend to focus on the research of vehicle dynamics by conducting performance tests on every system or some parts of the vehicle so as to improve the entire performance of the vehicle... Existing vehicle experiment systems tend to focus on the research of vehicle dynamics by conducting performance tests on every system or some parts of the vehicle so as to improve the entire performance of the vehicle.Virtual technology is widely utilized in various vehicle test-beds.These test-beds are mainly used to simulate the driving training,conduct the research on drivers'behaviors,or give virtual demonstrations of the transportation environment.However,the study on the active safety of the running vehicle in the virtual environment is still insufficient.A virtual scene including roads and vehicles is developed by using the software Creator and Vega,and radars and cameras are also simulated in the scene.Based on dSPACE's rapid prototyping simulation and its single board DS1103,a simulation model including vehicle control signals is set up in MATLAB/Simulink,the model is then built into C code,and the system defined file(SDF)is downloaded to the DS1103 board through the experiment debug software ControlDesk and is kept running.Programming is made by mixing Visual C++6.0,MATLAB API and Vega API.Control signals are read out by invoking library function MLIB/MTRACE of dSPACE.All the input,output,and system state values are acquired by arithmetic and are dynamically associated with the running status of the virtual vehicle.An intelligent vehicle experiment system is thus developed by virtue of program and integration.The system has not only the demonstration function,such as general driving,cruise control,active avoiding collision,but also the function of virtual experiment.Parameters of the system can be set according to needs,and the virtual test results can be analyzed and studied and used for the comparison with the existing models.The system reflects the running of the intelligent vehicle in the virtual traffic environment,at the same time,the system is a new attempt performed on the intelligent vehicle travel research and provides also a new research method for the development of intelligent vehicles. 展开更多
关键词 intelligent vehicle signals integration mix programming virtual experiments
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The Design and Implementation of Virtual Physics Experiment System based on VB Programming
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作者 Qingfang Hu 《International Journal of Technology Management》 2015年第1期47-49,共3页
This paper used the virtual reality modeling language (VRML) to establish the 3D virtual experiment instrument model, and by using the visual programming language VB to design and develop a interactive virtual reali... This paper used the virtual reality modeling language (VRML) to establish the 3D virtual experiment instrument model, and by using the visual programming language VB to design and develop a interactive virtual realization experiment platform, the interface has friendly interface, stable operation, strong practicability like with the Windows style, is a kind of reform for the traditional physics experiment teaching mode. The system has practical use value, also has reference value for the reform and modernization of other experimental courses. 展开更多
关键词 Physics experiment Computer assisted Instruction CAI courseware VB VRML
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Divergence of mating systems in Primula oreodoxa:Insights from transplant experiments and mating portfolios
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作者 Gui Zeng Kai Zhang +1 位作者 Dianxiang Zhang Shuai Yuan 《Plant Diversity》 2026年第1期169-180,共12页
Transitioning from outcrossing to self-fertilization is a widespread reproductive strategy in plants,especially in environments where pollination is limited.Despite its prevalence,this transition has rarely been exami... Transitioning from outcrossing to self-fertilization is a widespread reproductive strategy in plants,especially in environments where pollination is limited.Despite its prevalence,this transition has rarely been examined using transplant experiments,and previous studies have overlooked the contribution of the male parent in elucidating mating diversity.In this study,six transplanted populations were generated to investigate the relationship of the pollination environment with plant mating patterns and fecundity in Primula oreodoxa,a species that exhibits both distyly(predominantly outcrossing)and homostyly(predominantly selfing),based on data from 3582 individuals and 11 SSR markers.Homostylous plants had fruit and seed sets comparable to those of distylous plants at lower elevations but exhibited a clear reproductive advantage at higher elevations,particularly compared with the S morph.As elevation increased,the populational selfing rates increased,and the genetic diversity among the progeny was reduced.Furthermore,the visitation frequency of long-tongued pollinators was negatively and positively correlated with the selfing rate and number of mates,respectively,in the L and S morphs.In contrast,short-tongued pollinator visitation showed opposite correlations with the selfing rate and number of mates in homostylous morphs.In most populations,individuals functioned consistently as both female and male,and mating occurred randomly,suggesting a breakdown of the distyly polymorphism.Overall,our results provide experimental validation of the reproductive advantages of homostyly at high elevations by revealing that pollinator visitation shapes the selfing rate and mating diversity within populations,potentially driving the divergence of mating systems along environmental gradients. 展开更多
关键词 DISTYLY Mating portfolios OUTCROSSING Pollinators SELFING Transplant experiments
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Dynamic characteristics analysis of rack railway track system under traction conditions by experimental test
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作者 Zhihui Chen Guojun Yang +3 位作者 Zaigang Chen Haitao Zhang Jizhong Yang Wanming Zhai 《Railway Engineering Science》 2026年第1期40-54,共15页
The dynamic characteristics of the track system can directly affect its service performance and failure process.To explore the load characteristics and dynamic response of the track system under the dynamic loads from... The dynamic characteristics of the track system can directly affect its service performance and failure process.To explore the load characteristics and dynamic response of the track system under the dynamic loads from the rack vehicle in traction conditions,a systematic test of the track subsystem was carried out on a large-slope test line.In the test,the bending stress of the rack teeth,the wheel-rail forces,and the acceleration of crucial components in the track system were measured.Subsequently,a detailed analysis was conducted on the tested signals of the rack railway track system in the time domain and the time-frequency domains.The test results indicate that the traction force significantly affects the rack tooth bending stress and the wheel-rail forces.The vibrations of the track system under the traction conditions are mainly caused by the impacts generated from the gear-rack engagement,which are then transferred to the sleepers,the rails,and the ballast beds.Furthermore,both the maximum stress on the racks and the wheel-rail forces measured on the rails remain below their allowable values.This experimental study evaluates the load characteristics and reveals the vibration characteristics of the rack railway track system under the vehicle’s ultimate load,which is very important for the load-strengthening design of the key components such as racks and the vibration and noise reduction of the track system. 展开更多
关键词 Rack railway Vehicle-track coupled dynamics Traction condition experimental test Gear-rack engagement
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Systematic experimental investigation on pressure build-up characteristics of water-jet injection into a molten LBE pool 被引量:1
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作者 Hao-Ran Huang Zi-Jian Deng +1 位作者 Song-Bai Cheng Jia-Yue Chen 《Nuclear Science and Techniques》 2025年第1期161-174,共14页
In the scenario of a steam generator tube rupture accident in a lead-cooled fast reactor,secondary circuit subcooled water under high pressure is injected into an ordinary-pressure primary vessel,where a molten lead-b... In the scenario of a steam generator tube rupture accident in a lead-cooled fast reactor,secondary circuit subcooled water under high pressure is injected into an ordinary-pressure primary vessel,where a molten lead-based alloy(typically pure lead or lead-bismuth eutectic(LBE))is used as the coolant.To clarify the pressure build-up characteristics under water-jet injection,this study conducted several experiments by injecting pressurized water into a molten LBE pool at Sun Yat-sen University.To obtain a further understanding,several new experimental parameters were adopted,including the melt temperature,water subcooling,injection pressure,injection duration,and nozzle diameter.Through detailed analyses,it was found that the pressure and temperature during the water-melt interaction exhibited a consistent variation trend with our previous water-droplet injection mode LBE experiment.Similarly,the existence of a steam explosion was confirmed,which typically results in a much stronger pressure build-up.For the non-explosion cases,increasing the injection pressure,melt-pool temperature,nozzle diameter,and water subcooling promoted pressure build-up in the melt pool.However,a limited enhancement effect was observed when increasing the injection duration,which may be owing to the continually rising pressure in the interaction vessel or the isolation effect of the generated steam cavity.Regardless of whether a steam explosion occurred,the calculated mechanical and kinetic energy conversion efficiencies of the melt were relatively small(not exceeding 4.1%and 0.7%,respectively).Moreover,the range of the conversion efficiency was similar to that of previous water-droplet experiments,although the upper limit of the jet mode was slightly lower. 展开更多
关键词 Lead-cooled fast reactor Steam generator tube rupture accident Pressure build-up characteristics experimental study Pressure water-jet injection
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Hybrid CO_(2) thermal system for post-steam heavy oil recovery:Insights from microscopic visualization experiments and molecular dynamics simulations
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作者 Ning Lu Xiaohu Dong +4 位作者 Haitao Wang Huiqing Liu Zhangxin Chen Yu Li Deshang Zeng 《Energy Geoscience》 2025年第2期233-248,共16页
The hybrid CO_(2) thermal technique has achieved considerable success globally in extracting residual heavy oil from reserves following a long-term steam stimulation process.Using microscopic visualization experiments... The hybrid CO_(2) thermal technique has achieved considerable success globally in extracting residual heavy oil from reserves following a long-term steam stimulation process.Using microscopic visualization experiments and molecular dynamics(MD)simulations,this study investigates the microscopic enhanced oil recovery(EOR)mechanisms underlying residual oil removal using hybrid CO_(2) thermal systems.Based on the experimental models for the occurrence of heavy oil,this study evaluates the performance of hybrid CO_(2) thermal systems under various conditions using MD simulations.The results demonstrate that introducing CO_(2) molecules into heavy oil can effectively penetrate and decompose dense aggregates that are originally formed on hydrophobic surfaces.A stable miscible hybrid CO_(2) thermal system,with a high effective distribution ratio of CO_(2),proficiently reduces the interaction energies between heavy oil and rock surfaces,as well as within heavy oil.A visualization analysis of the interactions reveals that strong van der Waals(vdW)attractions occur between CO_(2) and heavy oil molecules,effectively promoting the decomposition and swelling of heavy oil.This unlocks the residual oil on the hydrophobic surfaces.Considering the impacts of temperature and CO_(2) concentration,an optimal gas-to-steam injection ratio(here,the CO_(2):steam ratio)ranging between 1:6 and 1:9 is recommended.This study examines the microscopic mechanisms underlying the hybrid CO_(2) thermal technique at a molecular scale,providing a significant theoretical guide for its expanded application in EOR. 展开更多
关键词 Heavy oil Hybrid CO_(2)thermal system Microscopic visualization experiment Molecular dynamics simulation Microscopic mechanism
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A Laboratorial Testing Scheme for 5G System:Channel Model Principle and Field Experiment Validation
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作者 Zhang Yuxiang Zhang Jianhua +7 位作者 Kang Yanan Zhao Mengxuan Qi Pan Zhang Zhen Tang Pan Tian Lei Liu Guangyi Yao Yuan 《China Communications》 2025年第9期113-128,共16页
As the commercialization of the fifth gen-eration communication(5G)is sped up,its system testing scheme is vital for the successful deployment of 5G.Especially,5G relies on the scale-increased multiple-input-multiple ... As the commercialization of the fifth gen-eration communication(5G)is sped up,its system testing scheme is vital for the successful deployment of 5G.Especially,5G relies on the scale-increased multiple-input-multiple output(MIMO)technique to improve its capacity and coverage.Thus,testing new functions of the 5G MIMO system accurately and ef-ficiently,including beamforming(beam-tracking with movement)and multiple-user(MU)multiplexing,is a challenging task.This paper tries to construct a lab-oratorial hardware and conduct equipment-controlled field testing.Firstly,the testing scheme is presented,which is composed of the framework,the channel models and the validation methods.Then,the channel model principles are explained in detail due to its di-rect influence on the testing accuracy.Specifically,we utilize the spatial consistency and the multi-link cor-relation properties to emulate the high-speed dynamic time-varying(HDT)and the multiple-cell(MC)-MU-MIMO channels.Finally,the above testing scheme is verified in a Shanghai 5G field experiment with the practical commercial equipment and the channel em-ulator.The results show that the 5G new functions are tested accurately and efficiently by switching the channel emulation configurations. 展开更多
关键词 channel model field experiment high-speed dynamic time-varying(HDT) multiple-cell-multiple-user-multiple-input-multiple-output(MC-MU-MIMO) testing scheme the fifth generation communication(5G)
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Application of Motic Digital Microscope Mutual System in the Experimental Teaching of Medicinal Plants
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作者 Hailin LU Min GUO +3 位作者 Shenggao YIN Bin LI Yonghua LI Haicheng WEN 《Medicinal Plant》 2025年第2期88-90,共3页
In comparison with conventional experimental teaching methods,the implementation of the Motic digital microscope mutual system in the experimental teaching of medicinal botany has been demonstrated to be a highly effi... In comparison with conventional experimental teaching methods,the implementation of the Motic digital microscope mutual system in the experimental teaching of medicinal botany has been demonstrated to be a highly efficacious approach to enhance the teaching level of experimental courses in medicinal botany.The implementation of a digital microscope mutual system in experimental teaching not only enhances students practical skills in laboratory operations but also increases classroom efficiency.Furthermore,it supports personalized development among students while fostering innovative thinking,independent learning capabilities,and analysis and problem-solving skills.Additionally,this approach contributes to the enhancement of students scientific literacy. 展开更多
关键词 MICROSCOPE Medicinal plants Mutual system experimental teaching
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Systems pharmacology and experimental evaluation to investigate the therapeutic targets of Chinese medicine QiShenYiQi in the treatment of ischemic stroke
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作者 Min Bai Na Cui +4 位作者 Qian Meng Yi-Wen Wang Ai-Dong Wen Xiao-Ming Wang Yi Ding 《Traditional Medicine Research》 2025年第5期42-53,共12页
Background:QiShenYiQi(QSYQ)is commonly accepted to treat ischemic stroke(IS)in clinical settings,yet the underlying mechanism of action of QSYQ is largely unknown.Methods:By combining systems pharmacology with experim... Background:QiShenYiQi(QSYQ)is commonly accepted to treat ischemic stroke(IS)in clinical settings,yet the underlying mechanism of action of QSYQ is largely unknown.Methods:By combining systems pharmacology with experimental assessment,we examined the key targets,bioactive components,and mechanisms of QSYQ against IS.Results:Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform predicted a total number of 254 targets that were potentially related to QSYQ,whereas 699 targets associated with IS were gathered from Therapeutic Target Database,Comparative Toxicogenomics Database,Gene Cards,Online Mendelian Inheritance in Man,and National Center for Biotechnology Information databases,and 83 of these targets overlap with QSYQ-related targets.Importantly,through the analysis of Gene Ontology functional annotation,Kyoto Encyclopedia of Genes and Genomes pathway enrichment,and protein-protein interaction network,we identified 20 related signaling pathways along with 4 hub genes.Subsequently,our molecular docking results revealed that QSYQ might interact with PTGS2,PTGS1,SCN5A,and HSP90AB1.We observed dose-dependent beneficial effects of QSYQ in significantly improving neurological function and alleviating histopathological damage in middle cerebral artery occlusion model,while decreasing infarct volume.Notablely,QSYQ markedly downregulates tumor necrosis factor-α,interleukin-6,and interleukin-1 beta.Overall,this study demonstrates the synergetic effects of QSYQ on regulating multi-targets in IS through inhibiting inflammatory processes and neuronal apoptosis,these findings may expand the understanding of QSYQ and provide guidance for its clinical application in treating IS.Conclusion:Current study reveals the protective roles of QSYQ against IS through modulating PTGS2/PTGS1/SCN5A/HSP90AB1 and TNF signaling pathways. 展开更多
关键词 QiShenYiQi ischemic stroke systems pharmacology experimental assessment
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A Novel Transcatheter Suture Closure System for Patent Foramen Ovale:An Experimental Study in Swine
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作者 Su Ye Luxi Guan +7 位作者 Dong Luo Fengwen Zhang Jianhua Lv Qizong Xie Qiao Huang Haiming Wu Haibo Hu Xiangbing Pan 《Congenital Heart Disease》 2025年第2期181-193,共13页
This study aimed to evaluate the feasibility,safety,and efficacy of a noveltranscatheter suture closure system(HaloStitch^(®))for patent foramen ovale(PFO)closure in a swine model.Methods:Thirteen swine underwent... This study aimed to evaluate the feasibility,safety,and efficacy of a noveltranscatheter suture closure system(HaloStitch^(®))for patent foramen ovale(PFO)closure in a swine model.Methods:Thirteen swine underwentexperimental PF0 model creation.All animals received implantationof the transcatheter suture closure system to evaluate procedural success.Comprehensive follow-up over sixmonths included serial ultrasound imaging,histopathological analysis,and gross anatomical exaninationof cardiac specimens.Results:Successful HaloStitch^(®)device implantation was adhieved in 11 of 13 swine.Gross anatomical examination confirrned secure positioning of all sutures in the atrial septum,with noredundancy or thrombus formation.Postoperative ultrasound demonstrated stable suture and staplepositions throughout follow-up,with no evidence of suture breakage,displacement,or thrombus.Stapleswere clearly visualized under ultrasound imaging,Both the atrial septal defect orifice diameter and residualseptal shunt flow velocity decreased significantly during the observation period.Histopathological analysisrevealed partially organized thrombi at the implant head and fibrous connective tissue encapsulation withlocalized inflammatory cell infiltration surrounding the polymer material.Conclsions:The transcathetersuture closure system(HaloStitch^(®))demonstrated feasibility,safety,and biocompatib ility for PFO closure ina swine model,supporting its potential for clinical translation. 展开更多
关键词 Patent foramen ovale transcatheter suture closure system experimental study
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Particle size ratios and ice content effects on rock-ice avalanche propagation and deposition:Flume experiments and DEM simulations
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作者 LUO Xin YANG Qingqing +1 位作者 HUO Zihao QIN Yao 《Journal of Mountain Science》 2026年第1期221-236,共16页
Rock-ice avalanches in cold high-mountain regions pose severe hazards due to their high mobility,yet the quantitative controls of particle-size ratio and ice content remain insufficiently constrained.This study invest... Rock-ice avalanches in cold high-mountain regions pose severe hazards due to their high mobility,yet the quantitative controls of particle-size ratio and ice content remain insufficiently constrained.This study investigates their coupled effects using inclinedflume experiments and Discrete Element Method(DEM)simulations,covering three gravel sizes(2-5 mm,5-7 mm,7-10 mm)and four ice-content levels(0%,20%,40%,60%).Run-out distance,velocity,energy components,flow regime(Savage number),and segregation indexαwere quantified.Increasing ice content significantly enhances mobility,but with diminishing marginal effectiveness.From 0%to 40%ice content,run-out distance increases by 41%-86%,whereas the additional increase from 40%to 60%contributes only 12%-23%.Particle-size ratio strongly governs segregation intensity.Fine-gravel groups reach segregation indices ofα=0.92-0.98,indicating nearly complete upward migration of ice,whereas medium-gravel and coarse-gravel groups exhibit much weaker segregation,stabilizing atα=0.68-0.74 and 0.60-0.69.Savage number analyses reveal marked flow-regime transitions.At 0%ice content,Savage numbers reach 1.0-1.5,indicating a collisional regime.Increasing ice content suppresses collisionality,with Savage numbers decreasing to 0.03-0.07 at 60%ice content,consistent with dense-regime flow.DEM energy analyses confirm this regime shift:for finegravel mixtures,collision energy decreases by 14%,while sliding-friction energy increases by 33%as ice content increases from 0%to 60%,reflecting enhanced overburden effects imposed by upward-segregated ice layers.Medium and coarse mixtures exhibit weaker or opposite energy-shift patterns,demonstrating strong size dependence.Mechanistically,large particle-size contrasts promote strong segregation and form dense basal rock layers that increase basal friction and reduce mobility.When particle sizes are similar or ice content is high,segregation remains limited,allowing ice to mix into the basal layer,thereby reducing basal friction and enhancing mobility.This research quantitatively demonstrates how composition controls particle spatial distribution,flow regime,and energy dissipation,offering new mechanistic insights into the propagation and deposition behaviors of rock-ice avalanches and improving hazard assessment in vulnerable high-mountain regions. 展开更多
关键词 Rock-ice avalanche DEM Flume experiment Ice content Particle size ratio SEGREGATION
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Recent advances in animal models for pathological scar research:A comprehensive review of experimental approaches and translational relevance
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作者 Diana-Larisa Ancuța Mariana Văduva +1 位作者 Cristin Coman Iuliana Caraș 《Animal Models and Experimental Medicine》 2026年第1期59-71,共13页
Pathological scarring,manifested in the form of hypertrophic scars(HTS)and keloid scars(KS),represents a major clinical challenge due to its aesthetic and functional implications for patients.Understanding the molecul... Pathological scarring,manifested in the form of hypertrophic scars(HTS)and keloid scars(KS),represents a major clinical challenge due to its aesthetic and functional implications for patients.Understanding the molecular mechanisms involved in these types of scars and developing effective treatments requires the use of controlled ex-perimental models,especially animals,to overcome the limitations of clinical studies.The aim of this sistematic review is to critically analyze the animal models used in the last five years(2020-2025)for the study of pathological scars,highlighting their advantages,limitations and applicability in the development of new therapeutic strat-egies.Murine,rabbit and porcine models,as well as alternative models,offer varied perspectives on the formation and treatment of HTS and KS,with an emphasis on histological and molecular correlations with human pathology.By synthesizing recent data,the paper highlights the essential role of preclinical research in optimizing an-tifibrotic treatments and in advancing the translation of data into the clinical sphere.Overall,animal models remain essential for bridging mechanistic insights with clinical translation,supporting the development of more effective and personalized anti-scar therapies. 展开更多
关键词 animal model experiment hypertrophic scar keloid scar TRANSLATION
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IN-CLASS DEMONSTRATION OF THE ZEEMAN EFFECT:FROM QUALITATIVE OBSERVATION TO QUANTITATIVE EXPERIMENTS
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作者 QIN Shaohan MA Yuhan 《物理与工程》 2026年第1期21-27,共7页
The Zeeman effect,a fundamental quantum phenomenon,demonstrates the interaction between magnetic fields and atomic systems.While precise spectroscopic measurements of this effect have advanced significantly,there rema... The Zeeman effect,a fundamental quantum phenomenon,demonstrates the interaction between magnetic fields and atomic systems.While precise spectroscopic measurements of this effect have advanced significantly,there remains a lack of simple,visually accessible demonstration for educational purposes.Here,we present a low-cost experiment that allows for direct visual observation of the Zeeman effect.Our setup involves a flame containing sodium(from table salt)placed in front of a sodium vapor lamp.When a magnetic field is applied to the flame,the shadow cast by the flame noticeably lightens,providing a clear,naked-eye demonstration of the Zeeman effect.Furthermore,we conduct two quantitative experiments using this setup,examining the effects of varying magnetic field strength and sodium concentration.This innovative approach not only enriches the experimental demonstration for teaching atomic physics at undergraduate and high school levels but also provides an open platform for students to explore the Zeeman effect through hands-on experience. 展开更多
关键词 Zeeman effect demonstration experiment CANDLE sodium vapor SHADOW
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Feasibility Analysis of Hypergravity Experiment of Density-Driven Convection of Dissolved CO_(2)
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作者 Ruiqi Chen Wenjie Xu +3 位作者 Yingtao Hu Yunmin Chen Jinlong Li Duanyang Zhuang 《Journal of Earth Science》 2026年第1期125-136,共12页
Dissolution trapping is one of the most promising mechanisms for safe geological carbon storage.Density-driven convection substantially accelerates the conversion of free-phase CO_(2)to the dissolved state,enhancing t... Dissolution trapping is one of the most promising mechanisms for safe geological carbon storage.Density-driven convection substantially accelerates the conversion of free-phase CO_(2)to the dissolved state,enhancing the sequestration safety.Since this process occurs on time scales of hundreds to thousands of years,reproducing it through conventional laboratory physical model tests is challenging.The hypergravity experiment reduces the model size and shortens the experimental time,enabling the modeling of gravity-driven flow processes at the field scale.However,it is uncertain whether the preferential flow effect caused by fractures can be reproduced in a hypergravity experiment.In this study,a three-dimensional discrete fracture-matrix model(3D-DFM)was used to evaluate the feasibility of hypergravity experiment of the transport of dissolved CO_(2)in fractured reservoirs.Numerical hypergravity tests were performed to examine the feasibility of modeling density-driven convection in homogeneous and heterogeneous media at different centrifuge accelerations.The hypergravity experiment can be used to study density-driven convection of dissolved CO_(2)at the field scale in homogeneous system.The numerical results show that the hypergravity experiment enables a faster breakthrough of plume and overestimates CO_(2)migration in the matrix surrounding the fractures. 展开更多
关键词 carbon sequestration dissolution trapping density-driven convection hypergravity experiment scaling laws fracture
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Behavior of opaque minerals in the Jilin H5 chondrite experimentally shocked to 12–133 GPa pressures
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作者 Xiande Xie Jiarui Lin Haiyang Xian 《Acta Geochimica》 2026年第1期30-41,共12页
Recovered samples of Jilin H5 chondrite experimentally shocked to 12-133 GPa were studied to explore the behavior of opaque minerals under shock loading using SEM-EDS,Raman spectroscopy,and TIMA.The following results ... Recovered samples of Jilin H5 chondrite experimentally shocked to 12-133 GPa were studied to explore the behavior of opaque minerals under shock loading using SEM-EDS,Raman spectroscopy,and TIMA.The following results were obtained.Firstly,at pressures lower than 53GPa,the opaque minerals still keep the unmelted state,while at 78 GPa and higher,FeNi metal and troilite form eutectic intergrowths occurring as disorderly fine veinlets filling the shock-induced fractures in silicate minerals.Secondly,single kamacite grains still maintain their contour at 12 GPa,but a part of brittle troilite grains was fragmented and squeezed into the shock-induced fractures within kamacite grains.At53 and 133 GPa,many more troilite fragments are poured in the kamacite interior to form disordered hybrid aggregates or to form squiggly strips,respectively.Similar phenomena are observed within single troilite grains,but the mineral squeezed into troilite grains is kamacite.Thirdly,chromite is a hard and refractory oxide mineral.When the shock pressure rises step by step from 12 to 133 GPa,the shock effect of chromite is only fragmentation.Its grain size decreases from tens of um at 53 GPa to a few um at 133 GPa.And,fourthly,native copper exhibits distinct redistribution behavior at high temperature.In Jilin samples shock-loaded to 12 GPa,copper initially located at troilite-kamacite interfaces partially transferred into small troilite grains containing fine FeNi particles.At 53 and 133 GPa,native copper preferentially transferred into larger troilite grains containing more particles of eutectic FeNi metal. 展开更多
关键词 Jilin chondrite Shock-recovery experiment High-pressure Metallic minerals Shock effects
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Quantitative analysis of flow characteristics within tundishes using dye experiments and image processing techniques
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作者 Hao-Jian Duan Ding-Han Li Li-Feng Zhang 《Journal of Iron and Steel Research International》 2026年第2期178-192,共15页
Image processing techniques were employed to analyze the ink dispersion process in a tundish water model,providing quantitative parameters to evaluate fluid flow dynamics.Key parameters,including filling time,dead are... Image processing techniques were employed to analyze the ink dispersion process in a tundish water model,providing quantitative parameters to evaluate fluid flow dynamics.Key parameters,including filling time,dead area fraction,area emptying time,peak concentration time,dead concentration fraction,and concentration emptying time,were introduced.Orthogonal tests were conducted to investigate the effects of dam spacing,height,and openings on tundish flow behavior.Results revealed that the dam spacing of 3760 mm yielded the shortest filling and peak concentration time,while the 4760 mm spacing minimized dead area and concentration fractions.Taller dams(620 mm)reduced dead area fractions but extended peak concentration time.Dams with openings demonstrated improved flow dynamics,reducing both dead area and concentration fractions,as well as emptying time.The consistency between dye experiments and residence time distribution experiments highlights the reliability of these parameters for optimizing tundish design and operation. 展开更多
关键词 TUNDISH Dye experiment Image processing technique Orthogonal test DAM
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Reform and Practice of Bioinformatics Experimental Teaching Based on Project-based Learning:A Case Study of"Influenza Virus Analysis"
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作者 Shuying FU Linqi HUANG +2 位作者 Yu MEN Wenwu TANG Meiying FENG 《Agricultural Biotechnology》 2026年第1期5-8,12,共5页
To meet the need for cultivating application-oriented talents in local universities,this study introduced a project-based learning approach into the reform of bioinformatics experimental teaching.The course was struct... To meet the need for cultivating application-oriented talents in local universities,this study introduced a project-based learning approach into the reform of bioinformatics experimental teaching.The course was structured around a project titled"Influenza Virus Analysis",comprising four progressive modules:database utilization and information retrieval,sequence alignment and phylogenetic analysis,functional and structural prediction,and omics data analysis.These modules were integrated into a coherent research workflow that connected fragmented knowledge and technical skills.During implementation,flipped classroom and group collaboration methods were employed,alongside the establishment of a diversified assessment system emphasizing process evaluation.Teaching practice indicates that the reform effectively enhances students professional application skills,learning experience,and scientific literacy,facilitating a shift from"tool operation"to"problem-solving"capabilities.This study provides a reference model for the reform of bioinformatics experimental teaching in local universities. 展开更多
关键词 Bioinformatics experiment Project-based learning Teaching reform Teaching practice Influenza virus
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Software and layout optimization of HIRFL-CSR external-target experiment
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作者 Jian-Wang Hong Chen-Lu Hu +29 位作者 Yu-Hong Yu Nu Xu Zhi-Yu Sun Hao Qiu Zhi-Gang Xiao Ming Shao Li-Min Duan Xiong-Hong He Zhi-Hui Xu Yi Wang Dong Han Zi-Xuan Chen Feng-Yi Zhao He-Run Yang Xiang-Lun Wei Rong-Jiang Hu Feng Liu Hua Pei Ya-Ping Wang Ye Tian Zhi Qin Dong-Dong Hu Guo-Dong Shen Li-Jun Mao Wei Wu Wei You Yu-Quan Chen Peng Yang De-Qing Fang Ya-Peng Zhang 《Nuclear Science and Techniques》 2026年第5期289-297,共9页
Heavy-ion collisions(HICs)is a unique experimental tool for investigating the properties of nuclear matter under extreme conditions in the laboratory.At HIRFL-CSR energies,HICs can create nuclear matter with 2-3 times... Heavy-ion collisions(HICs)is a unique experimental tool for investigating the properties of nuclear matter under extreme conditions in the laboratory.At HIRFL-CSR energies,HICs can create nuclear matter with 2-3 times the saturation density(ρ_(0)).The HIRFL-CSR external-target experiment(CEE)is a large-acceptance spectrometer designed to explore frontier topics in high-energy nuclear physics,such as the QCD phase structure and nuclear matter equation of states.In this letter,we introduce simulation and analysis software for the CEE experiment(CeeROOT).Based on the CEE conceptual design and CeeROOT software,the configurations of its subdetectors were optimized by considering foreseeable physical constraints.The final detector layout of the CEE spectrometer and its acceptances were validated through simulations of U+U collisions at 500 MeV/u and pp collisions at 2.8 GeV,which demonstrated that the CEE experiment will serve as a detector with wide acceptance and multi-particle identification capabilities for studying high-energy nuclear physics topics at HIRFL-CSR energies with pp,pA,and A A collisions. 展开更多
关键词 CEE experiment Simulation software OPTIMIZATION HIRFL-CSR
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Automated measurement method of clay-metal shear adhesion strength using machine learning and augmented experimental data
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作者 Zixu Zhu Chenghua Shi +4 位作者 Yingjie Sun Zuxian Wang Tao Zhu Haiyong Chen Jianbing Shuai 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第3期1923-1936,共14页
The shear adhesive strength at the clay‒metal interfaces serves as a critical parameter for evaluating the soil adhesion and metal interface mudding phenomena.However,its rapid determination remains challenging becaus... The shear adhesive strength at the clay‒metal interfaces serves as a critical parameter for evaluating the soil adhesion and metal interface mudding phenomena.However,its rapid determination remains challenging because of the demanding requirements for high-precision instrumentation and complex calibration procedures.In this study,an integrated framework was presented that combined physical experiments,theoretical approaches,and machine learning to enable the autonomous determination of the shear adhesive strength of soil under multiple influencing factors.We developed an improved particle swarm optimization-optimized ordinary kriging(IPOK)surrogate testing method to enhance the limited experimental datasets,and a lightweight residual neural network(RLNet)was then used for effective intra-and extra-domain predictions.A comprehensive model discussion,comparison,and interpretability analysis were conducted.The results from 64 physical experiments considering the consistency index,normal stress,clay content,rotation rate,and disc material effectively characterized the shear adhesion behaviour of kaolin.The IPOK surrogate experiments successfully replicated the physical data points while enriching the dataset details.The RLNet model trained with IPOK data achieved superior prediction performance,with a root mean square error of 7.491 and a determination coefficient of 0.927 in 16 orthogonal validation tests,and high similarity was attained between the predicted and measured values.A detailed model discussion analysis confirmed the superiority of the IPOK-RLNet framework.This methodology provides a cost-effective rapid analysis technique for assessing clay‒metal interface shear adhesion,significantly reducing laboratory testing requirements and experimental costs while increasing engineering efficiency. 展开更多
关键词 Clay‒metal interface Soil adhesion Shear adhesion strength Surrogated physical experiment Ordinary kriging Machine learning
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