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3D morphological characteristics of shrinkage porosities and their relationship with microstructures in Mg−12Al magnesium alloy
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作者 Chuang-ming LI Ang ZHANG +6 位作者 Yong-feng LI Heng-rui HU He LIU Yu-yang GAO Zhi-hua DONG Bin JIANG Fu-sheng PAN 《Transactions of Nonferrous Metals Society of China》 2026年第1期96-111,共16页
The dependence of shrinkage porosities on microstructure characteristics of Mg−12Al alloy was investigated.The distribution,morphology,size,and number density of shrinkage porosities were analyzed under different cool... The dependence of shrinkage porosities on microstructure characteristics of Mg−12Al alloy was investigated.The distribution,morphology,size,and number density of shrinkage porosities were analyzed under different cooling rates.The relationship between shrinkage porosities and microstructure characteristics was discussed in terms of temperature conditions,feeding channel characteristics,and feeding capacity.Further,the feeding behavior of the residual liquid phase in the solid skeleton was quantified by introducing permeability.Results show a strong correlation between the solid microstructure skeleton and shrinkage porosity characteristics.An increase in permeability corresponds to a declining number density of shrinkage porosities.This study aims to provide a more complete understanding how to reduce shrinkage porosities by controlling microstructure characteristics. 展开更多
关键词 Mg−12Al alloy shrinkage porosity SOLIDIFICATION microstructure characteristics morphological characteristics
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Sociodemographic characteristics of suicide attempters treated in the emergency department and the effect of psychological care
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作者 En-Sheng Tang Wan-Li Ren Hua Zou 《World Journal of Psychiatry》 2026年第1期116-124,共9页
BACKGROUND Appropriate care for individuals who attempt suicide and are admitted to the emergency department(ED)can prevent future suicidal behavior.It is vital to understand their sociodemographic characteristics and... BACKGROUND Appropriate care for individuals who attempt suicide and are admitted to the emergency department(ED)can prevent future suicidal behavior.It is vital to understand their sociodemographic characteristics and the effects of targeted psychological care.AIM To analyze sociodemographic characteristics of suicide attempters treated in the ED and evaluate the efficacy of psychological care.METHODS Data from 239 suicide attempters treated in the ED of the Central Hospital of Enshi Tujia and Miao Autonomous Prefecture(Hubei Province,China)between January 2021 and February 2025 were divided into 2:Control(n=108)and psychological care(n=131).The demographic characteristics and effects of the psychological care were analyzed.RESULTS The mean(±SD)age of the 239 patients[114 male(47.7%),125 female(52.3%)]was 26.25±9.3 years,of whom 122(45.2%)were single,117(48.9%)were married,and 106(44.4%)had secondary education.Thirty-eight(15.9%)patients had suicidal intent,with a mean of 1.26±0.59 suicide attempts each.Twenty-two(9.21%)patients had a family history of suicide,while 8(3.34%)had a family history of suicide attempt(s).Before intervention,mean Suicidal Intent Scale scores in the psychological nursing and control groups were 21.57±5.28 and 19.86±5.92,respectively(P>0.05).After 1 month of nursing intervention,the respective scores were 10.09±1.11 and 16.48±0.87(P<0.001);and the re-suicide rates were 11.45%(15/131)and 24.07%(26/108)(P<0.001).CONCLUSION Psychological care significantly reduces suicide risk;EDs should provide comprehensive mental health care. 展开更多
关键词 Emergency department Suicide attempts SUICIDE Psychological nursing Demographic characteristics
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Morphological characteristics and corresponding functional properties of homeostatic human microglia
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作者 Pariya Khodabakhsh Olga Garaschuk 《Neural Regeneration Research》 2026年第3期1112-1113,共2页
Microglia,the resident immune cells of the central nervous system,exhibit a wide array of functional states,even in their so-called“homeostatic”condition,when they are not actively responding to overt pathological s... Microglia,the resident immune cells of the central nervous system,exhibit a wide array of functional states,even in their so-called“homeostatic”condition,when they are not actively responding to overt pathological stimuli.These functional states can be visualized using a combination of multi-omics techniques(e.g.,gene and protein expression,posttranslational modifications,mRNA profiling,and metabolomics),and,in the case of homeostatic microglia,are largely defined by the global(e.g.,genetic variations,organism’s age,sex,circadian rhythms,and gut microbiota)as well as local(specific area of the brain,immediate microglial surrounding,neuron-glia interactions and synaptic density/activity)signals(Paolicelli et al.,2022).While phenomics(i.e.,ultrastructural microglial morphology and motility)is also one of the key microglial state-defining parameters,it is known that cells with similar morphology can belong to different functional states. 展开更多
关键词 functional properties multi omics techniques protein expressionposttranslational modificationsmrna profilingand homeostatic human microglia morphological characteristics resident immune cells homeostatic microgliaare protein expression
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Method for Detecting Multi-Modal Vibration Characteristics of Landmines 被引量:5
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作者 WANG Chi DUAN Naiyuan +2 位作者 WU Zhiqiang MA Hui ZHU Jun 《Instrumentation》 2018年第4期39-45,共7页
The acoustic vibration characteristics of landmines are investigated by means of modal analysis. According to the mechanical structure of landmines, a certain number of points are marked on the landmine shell to analy... The acoustic vibration characteristics of landmines are investigated by means of modal analysis. According to the mechanical structure of landmines, a certain number of points are marked on the landmine shell to analyze its multi-modal vibration characteristics, based on laser self-mixing interferometer and taking 69 plastic landmine as an example, the vibration detection experiment system is built to show the results of analytical method of multi-modal testing. The first and second order natural frequencies of the bricks are 38 HZ and 106 HZ, 112 HZ and 232 HZ for plastic landmines, and 74 HZ and 290 HZ for metal landmines. The first and second order natural frequencies of the bricks are far smaller than those of plastic landmines and metal landmines. This indicates that landmines show multi-modal vibration characteristics under external excitation, which are significantly different from those of bricks. The findings can be used for further research on acoustic landmines detection technology. 展开更多
关键词 multi-modal VIBRATION NATURAL Frequency VIBRATION MODE ACOUSTIC LANDMINES Detection
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深度翻译视角下的Chinese Characteristics汉译研究——以刘文飞、刘晓旸合译本为例
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作者 江治刚 李妙妙 《宜春学院学报》 2025年第7期96-103,共8页
民族志书写与翻译实践具有的天然相似性造就了民族志翻译鲜明的跨学科属性。本文以深度翻译为分析视角,选取刘文飞、刘晓旸父女合译的美国作家明恩溥民族志作品Chinese Characteristics的汉译本,通过考察该合译本为更好回归中文语境而... 民族志书写与翻译实践具有的天然相似性造就了民族志翻译鲜明的跨学科属性。本文以深度翻译为分析视角,选取刘文飞、刘晓旸父女合译的美国作家明恩溥民族志作品Chinese Characteristics的汉译本,通过考察该合译本为更好回归中文语境而采用的深度翻译策略的具体表现形式,旨在拓展深度翻译理论的应用领域,以期为民族志作品的无本回译实践提供有益借鉴。 展开更多
关键词 Chinese characteristics 深度翻译 刘文飞、刘晓旸合译本 民族志翻译 无本回译
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Construction and evaluation of a predictive model for the degree of coronary artery occlusion based on adaptive weighted multi-modal fusion of traditional Chinese and western medicine data 被引量:2
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作者 Jiyu ZHANG Jiatuo XU +1 位作者 Liping TU Hongyuan FU 《Digital Chinese Medicine》 2025年第2期163-173,共11页
Objective To develop a non-invasive predictive model for coronary artery stenosis severity based on adaptive multi-modal integration of traditional Chinese and western medicine data.Methods Clinical indicators,echocar... Objective To develop a non-invasive predictive model for coronary artery stenosis severity based on adaptive multi-modal integration of traditional Chinese and western medicine data.Methods Clinical indicators,echocardiographic data,traditional Chinese medicine(TCM)tongue manifestations,and facial features were collected from patients who underwent coro-nary computed tomography angiography(CTA)in the Cardiac Care Unit(CCU)of Shanghai Tenth People's Hospital between May 1,2023 and May 1,2024.An adaptive weighted multi-modal data fusion(AWMDF)model based on deep learning was constructed to predict the severity of coronary artery stenosis.The model was evaluated using metrics including accura-cy,precision,recall,F1 score,and the area under the receiver operating characteristic(ROC)curve(AUC).Further performance assessment was conducted through comparisons with six ensemble machine learning methods,data ablation,model component ablation,and various decision-level fusion strategies.Results A total of 158 patients were included in the study.The AWMDF model achieved ex-cellent predictive performance(AUC=0.973,accuracy=0.937,precision=0.937,recall=0.929,and F1 score=0.933).Compared with model ablation,data ablation experiments,and various traditional machine learning models,the AWMDF model demonstrated superior per-formance.Moreover,the adaptive weighting strategy outperformed alternative approaches,including simple weighting,averaging,voting,and fixed-weight schemes.Conclusion The AWMDF model demonstrates potential clinical value in the non-invasive prediction of coronary artery disease and could serve as a tool for clinical decision support. 展开更多
关键词 Coronary artery disease Deep learning multi-modal Clinical prediction Traditional Chinese medicine diagnosis
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TCM network pharmacology:new perspective integrating network target with artificial intelligence and multi-modal multi-omics technologies 被引量:1
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作者 Ziyi Wang Tingyu Zhang +1 位作者 Boyang Wang Shao Li 《Chinese Journal of Natural Medicines》 2025年第11期1425-1434,共10页
Traditional Chinese medicine(TCM)demonstrates distinctive advantages in disease prevention and treatment.However,analyzing its biological mechanisms through the modern medical research paradigm of“single drug,single ... Traditional Chinese medicine(TCM)demonstrates distinctive advantages in disease prevention and treatment.However,analyzing its biological mechanisms through the modern medical research paradigm of“single drug,single target”presents significant challenges due to its holistic approach.Network pharmacology and its core theory of network targets connect drugs and diseases from a holistic and systematic perspective based on biological networks,overcoming the limitations of reductionist research models and showing considerable value in TCM research.Recent integration of network target computational and experimental methods with artificial intelligence(AI)and multi-modal multi-omics technologies has substantially enhanced network pharmacology methodology.The advancement in computational and experimental techniques provides complementary support for network target theory in decoding TCM principles.This review,centered on network targets,examines the progress of network target methods combined with AI in predicting disease molecular mechanisms and drug-target relationships,alongside the application of multi-modal multi-omics technologies in analyzing TCM formulae,syndromes,and toxicity.Looking forward,network target theory is expected to incorporate emerging technologies while developing novel approaches aligned with its unique characteristics,potentially leading to significant breakthroughs in TCM research and advancing scientific understanding and innovation in TCM. 展开更多
关键词 Network pharmacology Traditional Chinese medicine Network target Artificial intelligence multi-modal Multi-omics
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Multi-modal intelligent situation awareness in real-time air traffic control: Control intent understanding and flight trajectory prediction 被引量:1
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作者 Dongyue GUO Jianwei ZHANG +1 位作者 Bo YANG Yi LIN 《Chinese Journal of Aeronautics》 2025年第6期41-57,共17页
With the advent of the next-generation Air Traffic Control(ATC)system,there is growing interest in using Artificial Intelligence(AI)techniques to enhance Situation Awareness(SA)for ATC Controllers(ATCOs),i.e.,Intellig... With the advent of the next-generation Air Traffic Control(ATC)system,there is growing interest in using Artificial Intelligence(AI)techniques to enhance Situation Awareness(SA)for ATC Controllers(ATCOs),i.e.,Intelligent SA(ISA).However,the existing AI-based SA approaches often rely on unimodal data and lack a comprehensive description and benchmark of the ISA tasks utilizing multi-modal data for real-time ATC environments.To address this gap,by analyzing the situation awareness procedure of the ATCOs,the ISA task is refined to the processing of the two primary elements,i.e.,spoken instructions and flight trajectories.Subsequently,the ISA is further formulated into Controlling Intent Understanding(CIU)and Flight Trajectory Prediction(FTP)tasks.For the CIU task,an innovative automatic speech recognition and understanding framework is designed to extract the controlling intent from unstructured and continuous ATC communications.For the FTP task,the single-and multi-horizon FTP approaches are investigated to support the high-precision prediction of the situation evolution.A total of 32 unimodal/multi-modal advanced methods with extensive evaluation metrics are introduced to conduct the benchmarks on the real-world multi-modal ATC situation dataset.Experimental results demonstrate the effectiveness of AI-based techniques in enhancing ISA for the ATC environment. 展开更多
关键词 Airtraffic control Automatic speechrecognition and understanding Flight trajectory prediction multi-modal Situationawareness
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Fabrication and Mechano-sensing Characteristics of Bending Polypyrrole Actuator
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作者 CHEN Jinyou HU Wei 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2025年第1期240-245,共6页
To prepare a conductive polymer actuator with decent performance,a self-built experimental platform for the preparation of polypyrrole film is employed.One of the essential goals is to examine the mechanical character... To prepare a conductive polymer actuator with decent performance,a self-built experimental platform for the preparation of polypyrrole film is employed.One of the essential goals is to examine the mechanical characteristics of the actuator in the presence of various combinations of process parameters,combined with the orthogonal test method of"four factors and three levels".The bending and sensing characteristics of actuators of various sizes are methodically examined using a self-made bending polypyrrole actuator.The functional relationship between the bending displacement and the output voltage signal is established by studying the characteristics of the actuator sensor subjected to various degrees of bending.The experimental results reveal that the bending displacement of the actuator tip almost exhibits a linear variation as a function of length and width.When the voltage reaches 0.8 V,the bending speed of the actuator tends to be stable.Finally,the mechanical properties of the self-assembled polypyrrole actuator are verified by the design and fabrication of the microgripper. 展开更多
关键词 conductive polymer POLYPYRROLE mechanical characteristics actuators sensing characteristics
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Dynamic deformation characteristics and microscopic analysis of xanthan gum-treated silty soil during wetting process 被引量:1
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作者 Junran Zhang Mengyi Jia +4 位作者 Tong Jiang Shoji Kato De'an Sun You Gao Zheng Yang 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第2期1149-1162,共14页
The deformation characteristics of silty soils under vibrational loads can easily change due to the wetting process,leading to the failure of roadbed structures.Commonly used methods for improving silty soils in engin... The deformation characteristics of silty soils under vibrational loads can easily change due to the wetting process,leading to the failure of roadbed structures.Commonly used methods for improving silty soils in engineering often yield unsatisfactory economic and ecological outcomes.As an environment-friendly soil improvement material,Xanthan gum has broad application prospects and is therefore considered a solidifying agent for enhancing silty soil properties in the Yellow River Basin.In this study,a series of tests is conducted using a scanning electron microscope and a dynamic triaxial testing apparatus to investigate the microstructure and dynamic deformation characteristics of unsaturated silty soil with varying xanthan gum contents during the wetting process.The results show that xanthan gum effectively fills voids between soil particles and adheres to their surfaces,forming fibrous and network structures.This modification enhances the inherent properties of the silty soil and significantly improves its stability under dynamic loading.Specifically,with increasing xanthan gum content,the dynamic shear modulus increases while the damping ratio decreases.During the wetting process,as suction decreases,the dynamic shear modulus decreases while the damping ratio increases.Xanthan gum reduces the sensitivity of the dynamic deformation characteristics of the treated silty soil to changes in suction levels.Finally,based on the modified Hardin-Drnevich hyperbolic model,a predictive model for the dynamic shear modulus and damping ratio of treated silty soil is proposed,considering the xanthan gum content.These research findings provide a theoretical basis for the construction and maintenance of water conservancy,slope stabilization,and roadbed projects in the Yellow River Basin. 展开更多
关键词 Xanthan gum Unsaturated silty soil dynamic deformation characteristics Scanning electron microscope Water retention characteristics
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Spatiotemporal characteristics and influencing factors of vegetation water use efficiency on the Tibetan Plateau in 2001-2020 被引量:2
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作者 HE Chenyang WANG Yanjiao +1 位作者 YAN Feng LU Qi 《Journal of Geographical Sciences》 2025年第1期39-64,共26页
Water use efficiency(WUE),as a pivotal indicator of the coupling degree within the carbon–water cycle of ecosystems,holds considerable importance in assessment of the carbon–water balance within terrestrial ecosyste... Water use efficiency(WUE),as a pivotal indicator of the coupling degree within the carbon–water cycle of ecosystems,holds considerable importance in assessment of the carbon–water balance within terrestrial ecosystems.However,in the context of global warming,WUE evolution and its primary drivers on the Tibetan Plateau remain unclear.This study employed the ensemble empirical mode decomposition method and the random forest algorithm to decipher the nonlinear trends and drivers of WUE on the Tibetan Plateau in 2001–2020.Results indicated an annual mean WUE of 0.8088 gC/mm·m^(2)across the plateau,with a spatial gradient reflecting decrease from the southeast toward the northwest.Areas manifesting monotonous trends of increase or decrease in WUE accounted for 23.64%and 9.69%of the total,respectively.Remarkably,66.67%of the region exhibited trend reversals,i.e.,39.94%of the area of the Tibetan Plateau showed transition from a trend of increase to a trend of decrease,and 26.73%of the area demonstrated a shift from a trend of decrease to a trend of increase.Environmental factors accounted for 70.79%of the variability in WUE.The leaf area index and temperature served as the major driving forces of WUE variation. 展开更多
关键词 water use efficiency spatiotemporal characteristic influencing factor Tibetan Plateau
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Source Characteristics and Induced Hazards of the 2025 M6.8 Dingri Earthquake,Xizang,China,Revealed by Imaging Geodesy 被引量:2
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作者 Chen Yu Zhenhong Li +11 位作者 Xiaoning Hu Chuang Song Suju Li Haihui Liu Jie Li Bingquan Han Zhenjiang Liu Ming Liu Shuang Zhu Xiaoye Hao Zhiyuan Li Jianbing Peng 《Journal of Earth Science》 2025年第2期847-851,共5页
0 INTRODUCTION.According to the China Earthquake Networks Center,an M6.8 earthquake struck Dingri County,Xizang Autonomous Region,China,on 7 January 2025 at 9:05 a.m.local time.The epicenter is located at 28.5°N,... 0 INTRODUCTION.According to the China Earthquake Networks Center,an M6.8 earthquake struck Dingri County,Xizang Autonomous Region,China,on 7 January 2025 at 9:05 a.m.local time.The epicenter is located at 28.5°N,87.45°E,with a depth of~10 km. 展开更多
关键词 source characteristics M earthquake Xizang imaging geodesy induced hazards Dingri China
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Personal Style Guided Outfit Recommendation with Multi-Modal Fashion Compatibility Modeling 被引量:1
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作者 WANG Kexin ZHANG Jie +3 位作者 ZHANG Peng SUN Kexin ZHAN Jiamei WEI Meng 《Journal of Donghua University(English Edition)》 2025年第2期156-167,共12页
A personalized outfit recommendation has emerged as a hot research topic in the fashion domain.However,existing recommendations do not fully exploit user style preferences.Typically,users prefer particular styles such... A personalized outfit recommendation has emerged as a hot research topic in the fashion domain.However,existing recommendations do not fully exploit user style preferences.Typically,users prefer particular styles such as casual and athletic styles,and consider attributes like color and texture when selecting outfits.To achieve personalized outfit recommendations in line with user style preferences,this paper proposes a personal style guided outfit recommendation with multi-modal fashion compatibility modeling,termed as PSGNet.Firstly,a style classifier is designed to categorize fashion images of various clothing types and attributes into distinct style categories.Secondly,a personal style prediction module extracts user style preferences by analyzing historical data.Then,to address the limitations of single-modal representations and enhance fashion compatibility,both fashion images and text data are leveraged to extract multi-modal features.Finally,PSGNet integrates these components through Bayesian personalized ranking(BPR)to unify the personal style and fashion compatibility,where the former is used as personal style features and guides the output of the personalized outfit recommendation tailored to the target user.Extensive experiments on large-scale datasets demonstrate that the proposed model is efficient on the personalized outfit recommendation. 展开更多
关键词 personalized outfit recommendation fashion compatibility modeling style preference multi-modal representation Bayesian personalized ranking(BPR) style classifier
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Relationship between dietary fiber physicochemical properties and feedstuff fermentation characteristics and their effects on nutrient utilization,energy metabolism,and gut microbiota in growing pigs 被引量:2
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作者 Feng Yong Bo Liu +6 位作者 Huijuan Li Houxu Hao Yueli Fan Osmond Datsomor Rui Han Hailong Jiang Dongsheng Che 《Journal of Animal Science and Biotechnology》 2025年第3期1269-1295,共27页
Background There is a growing focus on using various plant-derived agricultural by-products to increase the benefits of pig farming,but these feedstuffs are fibrous in nature.This study investigated the relationship b... Background There is a growing focus on using various plant-derived agricultural by-products to increase the benefits of pig farming,but these feedstuffs are fibrous in nature.This study investigated the relationship between dietary fiber physicochemical properties and feedstuff fermentation characteristics and their effects on nutrient utilization,energy metabolism,and gut microbiota in growing pigs.Methods Thirty-six growing barrows(47.2±1.5 kg)were randomly allotted to 6 dietary treatments with 2 apparent viscosity levels and 3β-glucan-to-arabinoxylan ratios.In the experiment,nutrient utilization,energy metabolism,fecal microbial community,and production and absorption of short-chain fatty acid(SCFA)of pigs were investigated.In vitro digestion and fermentation models were used to compare the fermentation characteristics of feedstuffs and ileal digesta in the pig’s hindgut.Results The production dynamics of SCFA and dry matter corrected gas production of different feedstuffs during in vitro fermentation were different and closely related to the physical properties and chemical structure of the fiber.In animal experiments,increasing the dietary apparent viscosity and theβ-glucan-to-arabinoxylan ratios both increased the apparent ileal digestibility(AID),apparent total tract digestibility(ATTD),and hindgut digestibility of fiber components while decreasing the AID and ATTD of dry matter and organic matter(P<0.05).In addition,increasing dietary apparent viscosity andβ-glucan-to-arabinoxylan ratios both increased gas exchange,heat production,and protein oxidation,and decreased energy deposition(P<0.05).The dietary apparent viscosity andβ-glucanto-arabinoxylan ratios had linear interaction effects on the digestible energy,metabolizable energy,retained energy(RE),and net energy(NE)of the diets(P<0.05).At the same time,the increase of dietary apparent viscosity andβ-glucan-to-arabinoxylan ratios both increased SCFA production and absorption(P<0.05).Increasing the dietary apparent viscosity andβ-glucan-to-arabinoxylan ratios increased the diversity and abundance of bacteria(P<0.05)and the relative abundance of beneficial bacteria.Furthermore,increasing the dietaryβ-glucan-to-arabinoxylan ratios led to a linear increase in SCFA production during the in vitro fermentation of ileal digesta(P<0.001).Finally,the prediction equations for RE and NE were established.Conclusion Dietary fiber physicochemical properties alter dietary fermentation patterns and regulate nutrient utilization,energy metabolism,and pig gut microbiota composition and metabolites. 展开更多
关键词 Dietary fiber Energy metabolism Fermentation characteristics Growing pigs Gut microbiota Nutrient utilization Physicochemical properties
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Hydraulic characteristics of a large rotation-angle baffle-drop shaft through synergetic discharge from dry and wet sides 被引量:1
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作者 Pei-de Liang Jun Chen +1 位作者 Teng Wu Jing Yan 《Water Science and Engineering》 2025年第1期115-124,共10页
To enhance the operational capacity and space utilization of baffle-drop shafts,this study improved the traditional baffle-drop shaft by expanding the wet-side space,incorporating large rotation-angle baffles,and inst... To enhance the operational capacity and space utilization of baffle-drop shafts,this study improved the traditional baffle-drop shaft by expanding the wet-side space,incorporating large rotation-angle baffles,and installing overflow holes in the dividing wall.A three-dimensional turbulent model was developed using ANSYS Fluent to simulate the hydraulic characteristics of both traditional and new baffle-drop shafts across various flow rates.The simulation results demonstrated that the new shaft design allowed for discharge from both the wet and dry sides,significantly improving operational capacity,with the dry side capable of handling 40%of the inlet flow.Compared to the traditional shaft,the new design reduced shaft wall pressures and decreased the mean and standard deviation of pressure on typical baffles by 21%and 63%,respectively,therefore enhancing structural safety.Additionally,the new shaft achieved a 2%-12%higher energy dissipation rate than the traditional shaft across different flow rates.This study offers valuable insights for the design and optimization of drop shafts in deep tunnel drainage systems. 展开更多
关键词 Baffle-drop shaft Synergetic discharge Fluent Numerical simulation Hydraulic characteristics
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Macro-and Microphysical Characteristics of Freezing Rain and Their Impacts on Wire Icing Mechanisms in the Southwestern Mountainous Areas of China 被引量:1
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作者 Yue ZHOU Chunsong LU +3 位作者 Jingjing Lü Xiaoyun SUN Lingli ZHOU Hui XIAO 《Advances in Atmospheric Sciences》 2025年第8期1620-1635,共16页
Based on comprehensive observations of 20 wire icing events during winter from 2019 to 2021,we investigated the characteristics of the icing properties,the atmospheric boundary layer structure,the raindrop size distri... Based on comprehensive observations of 20 wire icing events during winter from 2019 to 2021,we investigated the characteristics of the icing properties,the atmospheric boundary layer structure,the raindrop size distribution,and their associated effects on the ice accretion mechanism in the mountainous region of Southwest China.The maximum ice weight was positively correlated with the duration of ice accretion in the mountainous area.The duration of precipitation accounted for less than 20%of the icing period in the mountainous area,with solid-phase hydrometeors being predominant.Icing events,dominated by freezing rain(FR)and mixed rain–graupel(more than 70%),were characterized by glaze or highdensity mixed icing.The relationship between the melting energy and refreezing energy reflected the distribution characteristics of the proportion of FR under mixed-phase precipitation.The intensity of the warm layer and the dominant precipitation phase significantly affected the variations in the microphysical properties of FR.The melting of large dry snowflakes significantly contributed to FR in the mountainous areas,resulting in smaller generalized intercepts and larger mass-weighted mean diameters in the presence of a stronger warm layer.Under a weaker warm layer,the value of the massweighted mean diameter was significantly smaller because of the inability of large solid particles to melt.Finally,FR in the mountainous area dominated the ice weight during the rapid ice accumulation period.A numerical simulation of FR icing on wires effectively revealed the evolution of disaster-causing icing in mountainous areas. 展开更多
关键词 freezing rain wire icing macro-and microphysical characteristics mountainous area
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Study on the formation characteristics of underwater hemispherical shaped charge jet and its penetration performance into concrete 被引量:1
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作者 Chao Cao Jinxiang Wang +5 位作者 Lingquan Kong Kui Tang Yujie Xiao Yangchen Gu Ming Yang Jian Wang 《Defence Technology(防务技术)》 2025年第5期180-196,共17页
Shaped charge has been widely used for penetrating concrete.However,due to the obvious difference between the propagation of shock waves and explosion products in water and air,the theory governing the formation of sh... Shaped charge has been widely used for penetrating concrete.However,due to the obvious difference between the propagation of shock waves and explosion products in water and air,the theory governing the formation of shaped charge jets in water as well as the underwater penetration effect of concrete need to be studied.In this paper,we introduced a modified forming theory of an underwater hemispherical shaped charge,and investigated the behavior of jet formation and concrete penetration in both air and water experimentally and numerically.The results show that the modified jet forming theory predicts the jet velocity of the hemispherical liner with an error of less than 10%.The underwater jets exhibit at least 3%faster and 11%longer than those in air.Concrete shows different failure modes after penetration in air and water.The depth of penetration deepens at least 18.75%after underwater penetration,accompanied by deeper crater with 65%smaller radius.Moreover,cracks throughout the entire target are formed,whereas cracks exist only near the penetration hole in air.This comprehensive study provides guidance for optimizing the structure of shaped charge and improves the understanding of the permeability effect of concrete in water. 展开更多
关键词 Shaped charge jet Underwater penetration Formation characteristic Concrete failure
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Chemical characteristics and sources apportionment of volatile organic compounds in the primary urban area of Shijiazhuang,North China Plain 被引量:2
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作者 Xiao Zhang Junfeng Wang +8 位作者 Jiangwei Zhao Junliang He Yali Lei Kai Meng RuiWei Xue Zhang Miaomiao Zhang Shuangying Ni Eleonora Aruffo 《Journal of Environmental Sciences》 2025年第3期465-475,共11页
VOCs(Volatile organic compounds)exert a vital role in ozone and secondary organic aerosol production,necessitating investigations into their concentration,chemical characteristics,and source apportionment for the effe... VOCs(Volatile organic compounds)exert a vital role in ozone and secondary organic aerosol production,necessitating investigations into their concentration,chemical characteristics,and source apportionment for the effective implementation of measures aimed at preventing and controlling atmospheric pollution.FromJuly to October 2020,onlinemonitoringwas conducted in the main urban area of Shijiazhuang to collect data on VOCs and analyze their concentrations and reactivity.Additionally,the PMF(positive matrix factorization)method was utilized to identify the VOCs sources.Results indicated that the TVOCs(total VOCs)concentration was(96.7±63.4μg/m^3),with alkanes exhibiting the highest concentration of(36.1±26.4μg/m^3),followed by OVOCs(16.4±14.4μg/m^3).The key active components were alkenes and aromatics,among which xylene,propylene,toluene,propionaldehyde,acetaldehyde,ethylene,and styrene played crucial roles as reactive species.The sources derived from PMF analysis encompassed vehicle emissions,solvent and coating sources,combustion sources,industrial emissions sources,as well as plant sources,the contribution of which were 37.80%,27.93%,16.57%,15.24%,and 2.46%,respectively.Hence,reducing vehicular exhaust emissions and encouraging neighboring industries to adopt low-volatile organic solvents and coatings should be prioritized to mitigate VOCs levels. 展开更多
关键词 Volatile organic compounds Pollution characteristics Ozone formation potential OH radical loss rate Source apportionment
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Fluid evolution and fragmentation characteristics under high pressure water jet impact on thermal rock 被引量:1
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作者 Jianming Shangguan Zhaolong Ge +2 位作者 Qinglin Deng Yuhuai Cui Zhi Yao 《International Journal of Mining Science and Technology》 2025年第3期483-497,共15页
In the application of high-pressure water jet assisted breaking of deep underground rock engineering,the influence mechanism of rock temperature on the rock fragmentation process under jet action is still unclear.Ther... In the application of high-pressure water jet assisted breaking of deep underground rock engineering,the influence mechanism of rock temperature on the rock fragmentation process under jet action is still unclear.Therefore,the fluid evolution characteristics and rock fracture behavior during jet impingement were studied.The results indicate that the breaking process of high-temperature rock by jet impact can be divided into four stages:initial fluid-solid contact stage,intense thermal exchange stage,perforation and fracturing stage,and crack propagation and penetration stage.With the increase of rock temperature,the jet reflection angles and the time required for complete cooling of the impact surface significantly decrease,while the number of cracks and crack propagation rate significantly increase,and the rock breaking critical time is shortened by up to 34.5%.Based on numerical simulation results,it was found that the center temperature of granite at 400℃ rapidly decreased from 390 to 260℃ within 0.7 s under jet impact.In addition,a critical temperature and critical heat flux prediction model considering the staged breaking of hot rocks was established.These findings provide valuable insights to guide the water jet technology assisted deep ground hot rock excavation project. 展开更多
关键词 Fluid evolution Fragmentation characteristics Fracture process Water jet Thermal rock
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Electromechanical coupling vibration characteristics of high-speed train transmission system considering gear eccentricity and running resistance 被引量:1
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作者 Yeping Yuan Junguo Wang 《Acta Mechanica Sinica》 2025年第5期219-241,共23页
The gear transmission system directly affects the operational performance of high-speed trains(HST).However,current research on gear transmission systems of HST often overlooks the effects of gear eccentricity and run... The gear transmission system directly affects the operational performance of high-speed trains(HST).However,current research on gear transmission systems of HST often overlooks the effects of gear eccentricity and running resistance,and the dynamic models of gear transmission system are not sufficiently comprehensive.This paper aims to establish an electromechanical coupling dynamic model of HST traction transmission system and study its electromechanical coupling vibration characteristics,in which the internal excitation factors such as gear eccentricity,time-varying meshing stiffness,backlash,meshing error,and external excitation factors such as electromagnetic torque and running resistance are stressed.The research results indicate that gear eccentricity and running resistance have a significant impact on the stability of the system,and gear eccentricity leads to intensified system vibration and decreased anti-interference ability.In addition,the characteristic frequency of gear eccentricity can be extracted from mechanical signals and current signals as a preliminary basis for eccentricity detection,and electrical signals can also be used to monitor changes in train running resistance in real time.The results of this study provide some useful insights into designing dynamic performance parameters for HST transmission systems and monitoring train operational states. 展开更多
关键词 Gear eccentricity Electromechanical coupling Running resistance System stability Vibration characteristics
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