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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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Effects of intermediate principal stress on strainburst in granite:Insights from true-triaxial unloading experiments and PFC3D-GBM simulations
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作者 Hongru Li Manchao He +4 位作者 Tai Cheng Yafei Qiao Dongqiao Liu Jie Hu Yingming Xiao 《International Journal of Mining Science and Technology》 2026年第2期295-311,共17页
To improve the accuracy of rockburst risk evaluation in mining and tunnelling engineering,the influence of intermediate principal stress σ_(2) deserves further consideration,which has been neglected in general predic... To improve the accuracy of rockburst risk evaluation in mining and tunnelling engineering,the influence of intermediate principal stress σ_(2) deserves further consideration,which has been neglected in general prediction frameworks.This study employs an integrated approach that combines true-triaxial unloading experiments with three-dimensional grain-based discrete element modeling(PFC3D-GBM)to examine the effects of σ_(2) on strain systematically burst and elucidate the underlying mechanisms.Through this dual experimental–numerical methodology,the strainburst characteristics under varying σ_(2) are analyzed in detail regarding mechanical responses,failure evolution and patterns,microscope fracture mechanisms,and energy partitioning.The results indicate that elevated σ_(2) can enhance the bearing capacity of rock,thereby necessitating a higher stress condition required for strainburst.However,it also enlarges the potential strainburst intensity,manifesting as deeper rockburst pits and more violent ejection of rock fragments.An increasing σ_(2) facilitates the microscope transgranular fractures,inhibits intergranular tensile fractures,and raises the kinetic energy conversion ratio slightly.It affects the intensity of strainburst through the following mechanisms,including the increase of energy storage limit,the intensification of Poisson effect for lateral expansion,and the enhancement of the transgranular fracturing mechanism.In practical engineering,the depth and range of support needs to be ensured under high σ_(2) conditions,and it is recommended to use prestressing techniques to control the development of significant slabbing. 展开更多
关键词 ROCKBURST Intermediate principal stress True-triaxial experiment 3D grain-based model
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Selected Highlights from STAR Experiment
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作者 Jinhui Chen Zhenyu Chen +13 位作者 Maowu Nie Hao Qiu Shusu Shi Zebo Tang Qinghua Xu Chi Yang Shuai Yang Zaochen Ye Li Yi Wangmei Zha Chunjian Zhang Jinlong Zhang Yifei Zhang Xianglei Zhu 《Chinese Physics Letters》 2026年第3期10-26,共17页
In this paper,we review recent highlights in heavy-ion collisions and proton–proton collisions at top energies from STAR experiment at the Relativistic Heavy Ion Collider(RHIC) with key contributions from Chinese gro... In this paper,we review recent highlights in heavy-ion collisions and proton–proton collisions at top energies from STAR experiment at the Relativistic Heavy Ion Collider(RHIC) with key contributions from Chinese groups,including the quark–gluon plasma bulk properties,electromagnetic probes,heavy flavor and jets,antimatter hyper-nucleus,nuclear structure,global polarization,and nucleon spin structure.These data serve as important ingredients in the physics of quantum chromodynamics. 展开更多
关键词 electromagnetic probes quark gluon plasma heavy ion collisions star experiment proton proton collisions physics quantum chromodynamics relativistic heavy ion collider rhic
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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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Right patient approach to experimental stromal cell therapies for gastrointestinal tumors
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作者 Francesca Vescio Silvia Curcio +2 位作者 Isabella Aquila Michele Ammendola Alessandro Pasquale Tarallo 《World Journal of Gastrointestinal Oncology》 2026年第1期282-286,共5页
Experimental therapies targeting immune and stromal cells,such as mast cells,cancer-associated fibroblasts,dendritic cells,and tumor endothelial cells,in the treatment of gastrointestinal solid tumors pose new and com... Experimental therapies targeting immune and stromal cells,such as mast cells,cancer-associated fibroblasts,dendritic cells,and tumor endothelial cells,in the treatment of gastrointestinal solid tumors pose new and complex surgical and medico-legal challenges.These innovative treatments require that informed consent not be limited to simple acceptance of the medical procedure,but instead reflect a true relational and cognitive process grounded in understanding,free choice,and the ability to revoke consent at any time.In particular,it is essential that the patient understands the experimental nature of the therapy,its development stage,potential benefits and risks,as well as the implications for their health and personal dignity.In the case of stromal cell-based treatments,which may exert complex immunomodulatory effects or activate angiogenic pathways that are not yet fully understood,patients must be made fully aware that they are participating in a non-standardized therapy whose outcomes,whether beneficial or harmful,cannot yet be predicted with certainty.This requires particularly careful medical communication,using simple yet scientifically accurate explanations delivered in appropriate language,along with a final verification of the patient’s actual understanding. 展开更多
关键词 experimental therapies SURGERY Non-standardized treatment Gastrointestinal tumor Informed consent
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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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Cocrystal engineering for efficient separation of 4-bromo-3-methylphenol:Design of experiments,characterization,crystal structure and calculation
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作者 Chunxiao Wang Shuai Wang +2 位作者 Hongsen Zhang Chao Li Renzhong Qiao 《Chinese Journal of Chemical Engineering》 2026年第1期83-92,共10页
4-Bromo-3-methylphenol(BMP)is an important chemical intermediate with wide applications in the fields of medicine and pesticides.The synthesis of BMP from m-cresol via bromination is easy to carry out on an industrial... 4-Bromo-3-methylphenol(BMP)is an important chemical intermediate with wide applications in the fields of medicine and pesticides.The synthesis of BMP from m-cresol via bromination is easy to carry out on an industrial scale.However,due to the formation of regioisomeric impurities during bromination and the low melting point of BMP,the separation process is prone to the formation of oily substances,resulting in low yield and purity.In this work,a new cocrystallization engineering approach was proposed to separate and purify BMP.Through design of experiments,the cocrystallization process of BMP and triethylenediamine(DABCO)was optimized using a minimum-run resolution IV screening design combined with response surface methodology.In addition,the obtained 2BMP-DABCO powder was characterized by thermal analysis,powder X-ray diffraction,infrared spectroscopy,and scanning electron microscopy.Single crystals of 2BMP-DABCO were grown from acetone by slow evaporation,and detailed structural information was obtained through single-crystal X-ray diffraction.The self-assembly mechanism was further clarified by density functional theory calculations.This study provides a simple,robust,and scalable method for the production of BMP and offers a reference for the separation and purification of phenolic substances. 展开更多
关键词 4-Bromo-3-methylphenol TRIETHYLENEDIAMINE Cocrystallization engineering Design of experiments Crystal structure CALCULATIONS
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Optimal orthogonal block designs for threecomponent symmetric general blending models in mixture experiment
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作者 Jiawei Bao Yu Tang 《Statistical Theory and Related Fields》 2026年第1期117-134,共18页
In mixture experiments,the observed response is determined by the relative proportions of the components,consequently rendering the experimental region a simplex.This paper focuses primarily on the optimal designs of ... In mixture experiments,the observed response is determined by the relative proportions of the components,consequently rendering the experimental region a simplex.This paper focuses primarily on the optimal designs of mixture experiments that involve process variables.Prior research has extensively delved into optimal orthogonal block designs for some classic mixture models with process variables.Based on the framework of general blending models,this paper proposes a class of symmetric linear mixture models,which can be regarded as a generalization of many existing ones.Under the orthogonal blocking conditions,orthogonal block designs are devised through Latin squares in the presence of process variables.TheD-,A-,and E-optimality criteria are utilized to obtain optimal designs at the boundary of the simplex in the case of 3 components.As the values of the exponents change,numerically derived optimal design points are presented to illustrate the pattern of their variations,and to verify the consistency of the results with previous research on some specific symmetric general blending models. 展开更多
关键词 Mixture experiments general blending models optimal designs orthogonal Latin squares block designs
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Vibrations induced by time-delayed double blastholes in underground rocks:Experimental study and theoretical analysis
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作者 Yonggang Gou Gui Yang +2 位作者 Xianyang Qiu Kun Ji Yumin Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1108-1125,共18页
Time-delayed blasting is widely utilized in engineering to mitigate induced vibration hazards and enhance fragmentation.The underlying vibration reduction principle is the decrease of the charge weight per delay,while... Time-delayed blasting is widely utilized in engineering to mitigate induced vibration hazards and enhance fragmentation.The underlying vibration reduction principle is the decrease of the charge weight per delay,while the potential for further vibration reduction remains debated,largely due to unclear underlying mechanisms.In light of the popularization of electronic detonators and the representativeness of double-hole configurationsfor multiple blastholes,it is essential to investigate the vibration characteristics induced by time-delayed double blastholes.Therefore,a series of doubleborehole experimental blasts was conducted in an underground roadway to clarify the variation in vibration from single-hole to dual-hole conditions.Based on the experimental data and inherent limitations,an exact full-fieldtheoretical model was further employed to systematically analyze the effects of delay time,charge length,and borehole inclination angle on vibrations induced by various doublehole configurations.The experimental data and theoretical analysis reveal that the general scaled distance effectively predicts vibrations in delayed blasting but does not reflectvibration reduction.Increasing delay time causes fluctuatingPPVs,which stabilize slightly above single-hole PPVs as delay times exceed a certain value.The delayed blasting primarily reduces near-fieldfrequencies.Longer charge lengths in double boreholes increase PPV levels and attenuation rates within a certain length,and the vibration behavior of combined long and short charge lengths is governed by the long blasthole.Larger blasthole inclination angles enhance vibration amplitude and reduce PPV attenuation rates.Optimizing inclination angles is more critical than adjusting delay times,and parallel boreholes offer the best vibration control. 展开更多
关键词 Vibration of double blastholes experimental data Theoretical model Delay time Wave superposition
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Heat exchange during fluid seepage and heat transfer in EGS heat extraction:Insights from laboratory experiments
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作者 Peng Zhao Haiyan Zhu +4 位作者 Fengshou Zhang Xuanhe Tang Shijie Chen Lei Tao John D.McLennan 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第3期1954-1965,共12页
Fluid seepage and associated heat transfer within the enhanced geothermal system(EGS)regulate the extraction of heat from hot,low-water-saturation thermal reservoirs,sometimes referred to as hot dry rock(HDR).To under... Fluid seepage and associated heat transfer within the enhanced geothermal system(EGS)regulate the extraction of heat from hot,low-water-saturation thermal reservoirs,sometimes referred to as hot dry rock(HDR).To understand these complex heat recovery processes,we simulated long-term heat extraction in a surrogate HDR using a true triaxial apparatus.A circulation test was first implemented to analyze the connectivity between different wells.Suitable injection and production wells were then selected for the laboratory heat extraction tests in granite,which lasted 14.5 h.Under variable injection rate conditions,we systematically analyzed the time-varying curves of temperature and flow rate in the production wells and pressure in the injection wells.Our findings showed that the advantage channel was dominant in the flow distribution when several paths existed in EGS.Changes in fracture conductivity are attributed to injection pressure.These included an increase in fracture width and activation of a localized closed area of fracture.These two mechanisms influenced the production temperature,and this is consistent with the field data monitored at the Fenton Hill and Hijiori projects.Fluid leak-off was an important factor affecting the production flow rate.For a fracture with low hydraulic conductivity,a lower injection rate could effectively prevent excessive fluid leak-off.In addition,by comparing injection rates and fluid recovery rates,production wells in different phases or injection modes had different fluid recovery rates even when the injection rates were the same. 展开更多
关键词 Hot dry rock geothermal exploitation Laboratory experiments Fluid leak-off Mechanism of fluid seepage Heat exchange performance
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Innovative Experiments on Ship Resistance Performance in Managed Ice Floe Fields
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作者 LIU Ren-wei LUO Xu-cheng +3 位作者 BAI Xiao-long D.A.Semenov ZHANG Jian ZHANGLi-xuan 《China Ocean Engineering》 2025年第1期58-72,共15页
In this work,the selected icebreaker model experiment is performed in a towing tank.We focus on the influence of seawater salinity on ship ice resistance in the ice floe field and the innovative ice model and ship mod... In this work,the selected icebreaker model experiment is performed in a towing tank.We focus on the influence of seawater salinity on ship ice resistance in the ice floe field and the innovative ice model and ship model test technology,including the similitude rule of ship model tests,test principles,and validation with full-scale ship data.A formula for calculating the relationship between the temperature and salinity of the water is constructed,which can be used to simulate the role of seawater in freshwater ice pools.On this basis,the effect of salinity on the resistance of ships sailing in broken ice fields is studied.A technique in which artificial ice made of polyethylene spheres is used to simulate ice resistance is proposed.With a series of ship model experiments in spherical and triangular ice fields,the effects of salinity and velocity on the ice resistance test of the ship model are analyzed.A relationship of the ice resistance of the ship model to the spherical ice field and the triangular ice field is proposed.The conversion results are consistent with onsite data of the full-size ship,which verifies the method of converting the test results of the ship model to the prototype. 展开更多
关键词 ice resistance ice load ship-ice interaction ship-ice experiment model ice experiment artificial ice
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Screening of TiB2-based ternary composites for X-ray transparent heaters in high-pressure and high-temperature experiments
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作者 Yutian Zhang Guoliang Niu +4 位作者 Pengfei Tan Chuanhui Zhu Huiyang Gou David Walker Man-Rong Li 《Matter and Radiation at Extremes》 2025年第6期122-130,共9页
High-pressure and high-temperature(HPHT)experiments in large-volume presses(LVPs)benefit from reliable,available,and affordable heaters to achieve stable and homogeneous heating and,in some circumstances,X-ray transpa... High-pressure and high-temperature(HPHT)experiments in large-volume presses(LVPs)benefit from reliable,available,and affordable heaters to achieve stable and homogeneous heating and,in some circumstances,X-ray transparency for monitoring of properties of an in situ experiment using X-ray diffraction and contrast imaging techniques.We have developed heaters meeting the above requirements,and we screen the ternary system TiB2–SiC–hexagonal(h)BN(denoted as TSB)to enable manufacture of X-ray transparent heaters for HPHT runs.Heaters fabricated using optimized TSB-631(60%TiB2–30%SiC–10%hBN by weight)have been tested in modified truncated assemblies,showing excellent performance up to 22 GPa and 2395 K in HPHT runs.TSB-631 has good ceramic machinability,outstanding reproducibility,high stability,and negligible temperature gradient for runs at 3–7 GPa with cell assemblies with truncated edge lengths of 8–12 mm.The fabricated heaters not only show excellent performance in HPHT runs,but also demonstrate high X-ray transparency over a wide X-ray wavelength region,indicating potential applications for in situ X-ray diffraction/imaging under HPHT conditions in LVPs and other high-pressure apparatus. 展开更多
关键词 TIB monitoring properties Hexagonal boron nitride X ray transparent heaters large volume presses Ternary composites situ experiment high pressure high temperature experiments
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