检索结果-内蒙古大学图书馆

Study on Cyclic Mechanical Behavior and Damage Constitutive of PVA Fiber Recycled Aggregate Concrete

Iranian Journal of Science and Technology - Transactions of Civil engineering 2024年第6期48卷 4113-4130页

作者： Liu, Kang Lin, Guiwu Chen, Yuliang Li, Hao Department of Civil Engineering Guangxi University of Science and Technology Liuzhou 545006 China Guangxi Engineering Research Center for Safety Prevention and Control of Assembly Structure Liuzhou 545006 China Key Laboratory of Disaster Prevention & amp

The cyclic mechanical properties and damage evolution of polyvinyl alcohol fiber recycled aggregate concrete (PVA-FRAC) play an important role in predicting the response of recycled aggregate concrete structures under earthquake. Therefore, 32 cylindrical specimens were designed and fabricated with different PVA fiber volume content (0.05%, 0.1%, and 0.15%), recycled aggregate replacement rates (0%, 30%, 50%, 70%, and 100%), and loading rates (0.002 and 0.005 mm/s). Monotonic and cyclic compressive loading tests were carried out, and the failure process and morphology of the specimens were observed. The failure mechanism of PVA-FRAC was analyzed from macro and micro-perspectives. The experimental results show that oblique splitting failure mainly occurs in PVA fiber recycled concrete under cyclic loading. With the increase in the replacement rate of recycled aggregate, the main crack is prominent and the crack width is increasing. PVA fiber and appropriate replacement ratio of recycled aggregate can effectively improve the ductility and energy dissipation capacity of concrete. However, the larger content of PVA fiber will lead to the decrease in the performance of concrete. The energy dissipation capacity is the best when the volume content of PVA fiber is 0.10%, the increase is 26.19%, and the overall modification is the best. With the help of scanning electron microscope (SEM), it is found that PVA fiber can effectively inhibit the development of cracks perpendicular to the fiber direction and improve the energy dissipation capacity of concrete. In addition, a PVA-FRAC damage constitutive model is proposed based on the damage evolution law. It can better reflect the stress–strain relationship and damage evolution process of PVA-FRAC under cyclic loading. It can provide reference for the engineering application of PVA-FRAC and the revision of related regulations. © The Author(s), under exclusive licence to Shiraz University 2024.

关键词： Cyclic compression Failure mechanism Mechanical properties Polyvinyl alcohol fiber Recycled aggregate concrete

来源：评论

学校读者我要写书评

暂无评论

Layered metastructure containing freely-designed local resonators for wave attenuation

引用

Defence Technology（防务技术） 2024年第2期32卷 23-31页

作者： Yu Li Huguang He Jiang Feng Hailong Chen Fengnian Jin Hualin Fan State Key Laboratory for Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of PLANanjing 210007China Rocket Force University of Engineering Xi'an 710025China Henan International Joint Laboratory of Dynamics of Impact and Disaster of Engineering Structures Department of Civil EngineeringNanyang Institute of TechnologyNanyang 473004China Guangxi Key Laboratory of Disaster Prevention and Engineering Safety and Key Laboratory of Disaster Prevention and Structural Safety of Ministry of EducationCollege of Civil Engineering and ArchitectureGuangxi UniversityNanning 530004China Research Center of Lightweight Structures and Intelligent Manufacturing State Key Laboratory of Mechanics and Control of Mechanical StructuresNanjing University of Aeronautics and AstronauticsNanjing 210016China

Combining periodic layered structure with three-dimensional cylindrical local resonators,a hybrid metastructure with improved wave isolation ability was designed and investigated through theoretical and numerical *** metastructure is composed of periodic rubber layers and concrete layers embedded with three-dimensional resonators,which can be freely designed with multi local resonant frequencies to attenuate vibrations at required frequencies and widen the attenuation *** metastructure can also effectively attenuate seismic *** with layered rubber-based structures,the metastructure has more excellent wave attenuation effects with greater attenuation and wider bandgap.

关键词： Layered metastructure Local resonator Wave attenuation

来源：评论

学校读者我要写书评

暂无评论

A review of underground transport infrastructure monitoring in CCS: Technology and engineering Practice

引用

Process Safety and Environmental Protection 2024年 190卷 726-745页

作者： Peng, Haoyan Xu, Zhao-Dong Lu, Hongfang Xi, Dongmin Xia, Zhiheng Yang, Cen Wang, Bohong China-Pakistan Belt and Road Joint Laboratory on Smart Disaster Prevention of Major Infrastructures Southeast University Nanjing 210096 China National & Local Joint Engineering Research Center of Harbor Oil & Gas Storage and Transportation Technology/Zhejiang Key Laboratory of Petrochemical Environmental Pollution Control Zhejiang Ocean University Zhoushan 316022 China

Carbon capture and storage (CCS) plays a vital transitional role in carbon sinks, which is an international research hotspot. CO2 pipelines and injection wells are the most common transport methods for transporting CO... 详细信息

Carbon capture and storage (CCS) plays a vital transitional role in carbon sinks, which is an international research hotspot. CO₂ pipelines and injection wells are the most common transport methods for transporting CO₂ from the capture site to the storage space, which are underground transport infrastructure. Despite the global significance of underground transport infrastructure of CCS, research on its monitoring remains limited, and there is a scarcity of relevant engineering specifications due to the under development of CCS. This paper proposes a three-level monitoring framework based on the characteristics of the monitoring sensing technology, and summarizes various monitoring methods, engineering practice of monitoring, current challenges and future development trends of underground transport infrastructure of CCS based on the structural characteristics, failure characteristics of underground transport infrastructure of CCS. Through the summary of existing engineering projects and academic research, there is a more comprehensive and in-depth understanding of the current and future monitoring technologies of underground transport infrastructure of CCS, which will contribute to enhancing process safety and disaster prevention and control in CCS operations. © 2024

关键词： CO2 injection well CO2 pipeline engineering practice Monitoring technology

来源：评论

学校读者我要写书评

暂无评论

Single-atom Pd anchored in the porphyrin-center of ultrathin 2D-MOFs as the active center to enhance photocatalytic hydrogen-evolution and NO-removal

引用

Chinese Chemical Letters 2024年第9期35卷 364-368页

作者： Xingyan Liu Chaogang Jia Guangmei Jiang Chenghua Zhang Mingzuo Chen Xiaofei Zhao Xiaocheng Zhang Min Fu Siqi Li Jie Wu Yiming Jia Youzhou He Chongqing Key Laboratory of Catalysis and New Environmental Materials College of Environment and ResourcesChongqing Technology and Business UniversityChongqing 400067China School of Pharmacy North Sichuan Medical CollegeNanchong 637100China Carbon Neutrality Technology Application Research Center College of River and Ocean EngineeringChongqing Jiaotong UniversityChongqing 400074China State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China National Local Joint Engineering Research Center for Road Engineering and Disaster Prevention and Reduction Technology in Mountainous Areas China Merchants Chongqing Communications Technology Research and Design Institute Co.Ltd.Chongqing 400067China Chongqing Culture Relics and Archaeology Research Institute Chongqing 400013China

Single-atom catalysts were widely used to treat atmospheric pollution and alleviate energy crises through ***,how to prevent the aggregation of single atoms during the preparation and catalytic processes remained a great ***,a novel ultrathin two-dimensional porphyrin-based single-atom photocatalyst Ti-MOF(abbreviated as TMPd)obtained through a simple hydrothermal synthesis strategy was used for photocatalytic hydrogen evolution and NO removal,in which the singleatom Pd tightly anchored in the center of porphyrin to ensure single-atom Pd stable *** with most reported MOFs-based photocatalysts,the TMPd showed an excellent hydrogen evolution rate(1.32 mmol g^(-1)h^(-1))and the NO removal efficiency(62%)under visible light *** high-angle annular dark-field scanning transmission electron microscope(HAADF-STEM)and synchrotron-radiation-based X-ray absorption fine-structure spectroscopy(XAFS)proved that pd in TMPd existed in an isolated state,and the atomic force microscope(AFM)proved the ultrathin morphology of *** calculations had demonstrated that single-atom Pd could serve as the active center and more effectively achieve electron transfer,indicating that single-atom Pd played a vital role in photocatalytic hydrogen *** addition,a possible photocatalytic pathway of NO removal was proposed based on ESR and in-situ infrared spectra,in which the catalysts anchored with single-atom Pd could produce more active substances and more effectively oxidize NO to NO_(2)^(-)or NO_(3)^(-).The results suggested that coordinating single-atom metal species as the active site in the center of porphyrin could be a feasible strategy to obtain various ultrathin porphyrin-based single-atom photocatalysts to acquire excellent photocatalytic performance further.

关键词： Porphyrin-based MOFs Single-atom Pd Ultrathin 2D nanosheets Hydrogen evolution NO removal

来源：评论

学校读者我要写书评

暂无评论

Seismic behaviors of utility tunnel-soil system: With and without joint connections

引用

Underground Space 2022年第5期7卷 798-811页

作者： Liang Han Hanlong Liu Wengang Zhang Xuanming Ding Zhixiong Chen Li Feng Zhenyu Wang School of Civil Engineering Chongqing UniversityChongqing 400044China Key Laboratory of New Technology for Construction of Cities in Mountain Area Chongqing UniversityChongqing 400044China National Joint Engineering Research Center of Geohazards Prevention in the Reservoir Areas Chongqing UniversityChongqing 400044China Key Laboratory of Mining Disaster Prevention and Control Shandong University of Science and TechnologyQingdao 266590China

Seismic responses of utility tunnel-soil system were studied via shaking table model tests with considerations of two kinds of double box utility tunnels:with and without joint *** two testing utility tunnel models were made of galvanized iron wire and micro-concrete,and the ground was simulated by the dry standard sand through layered tamping *** utility tunnel-soil system was subjected to horizontal vibration in uniaxial direction perpendicular to the longitudinal direction of tunnel *** instrumentations of earth pressure gauges,accelerometers and strain gauges,the earth pressure response,acceleration response and bending moment response were *** testing results show that the joint connections in the utility tunnel along the longitudinal direction play an important role in determining the characteristic of earth pressure response and bending moment response,whereas the effect of joint connections on acceleration response is less *** addition,the partition wall exhibits the consistent acceleration response with the side-wall of double box utility tunnel model under seismic *** on the testing results,it is suggested that the joint connection should be taken reasonably into consideration during design and construction for engineering practice.

关键词： Utility tunnel joint connections Seismic behaviors Shaking table Model test

来源：评论

学校读者我要写书评

暂无评论

The lackage in the research of parallel tunnels interaction with a supporting structure in a huge slope: a review

引用

Discover Civil engineering 2025年第1期2卷 1-27页

作者： Suliman, Lojain Liu, Xinrong Zhou, Xiaohan National Joint Engineering Research Center of Geohazards Prevention in the Reservoir Areas (Chongqing) Chongqing China State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing China College of Civil Engineering Chongqing University Chongqing China State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing University Chongqing China

Due to urbanization and land constraints in metropolitan areas, there has been an increase in demand for underground construction in recent years. Settlement is always induced by tunneling. Ground settlement as a result of digging shallow tunnels is therefore a frequent occurrence. In order to maintain control over the settlement, it should be able to predict it and take the appropriate safety measures. Even the settlement characteristics due to the excavation of twin the tunnel have been studied extensively. However, the parallel tunnel interaction with other structures in a huge slope has not been studied. This paper aims to review the previous settlement characteristics due to tunneling when parallel tunnels have an interaction process during the excavation. The specific objective of this study is to expand the understanding of settlement behavior in tunneling under large slopes with focusing on the interaction mechanism, which is underexplored in comparison to flat terrains. The capabilities and limitations in the settlement characteristics during the tunneling process have been revised. Furthermore, the gapes in describing the settlement and the lack of studies that accompany the phenomena has been revealed.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Advanced modeling of the absorption enhancement of black carbon particles in chamber experiments by considering the morphology and coating thickness

引用

Frontiers of Environmental Science & engineering 2024年第9期18卷 129-142页

作者： Xiaodong Wei Jianlin Hu Chao Liu Xiaodong Xie Junjie Yin Song Guo Min Hu Jianfei Peng Huijun Wang Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and EngineeringNanjing University of Information Science&TechnologyNanjing 210044China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Key Laboratory of Meteorological Disaster(Ministry of Education)Nanjing University of Information Science and TechnologyNanjing 210044China Nansen−Zhu International Research Centre Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China East China Air Traffic Management Bureau CAAC Shanghai 200335China State Key Joint Laboratory of Environmental Simulation and Pollution Control International Joint Laboratory for Regional Pollution Control(IJRC)(Ministry of Education)College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China Tianjin Key Laboratory of Urban Transport Emission Research&State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control College of Environmental Science and EngineeringNankai UniversityTianjin 300071China

Measurements studies have shown that the absorption of radiation by black carbon(BC)increases as the particles ***,there are significant discrepancies between the measured and modeled absorption enhancement(E_(abs)),largely due to the simplifications used in modeling the mixing states and shape *** took advantage of chamber experiments on BC aging and developed an efficient method to resolve the particle shape based on the relationship between the coating fraction(ΔD_(ve)/D_(ve),0)and fractal dimension(D_(f)),which can also reflect the variations of D_(f)during the whole BC aging *** with externally and partly mixed states(0≤ΔD_(ve)/D_(ve),0≤0.5)can be considered to be uniformly distributed with the D_(f)values of 1.8–2.1,whereas the Df values are constrained in the range 2.2–2.8 for fully mixed states(ΔD_(ve)/D_(ve),0>0.5).The morphological parameters(i.e.,the effective density and the dynamic shape factor)were compared with the measured values to verify the simulated *** simulated mean deviations of morphological parameters were smaller than 8%for the method resolving the particle *** applying a realistic shape and refractive index,the mass absorption cross for fully mixed states can be improved by 11%compared with a simplified core–shell *** on our understanding of the influence of D_(f)andΔD_(ve)/D_(ve),0 on E_(abs),we propose a two-stage calibration equation to correct the E_(abs)values estimated by the core–shell model,which reduces the simulation error in the Mie calculation by 6%–14%.

关键词： Black carbon Mixing states Fractal dimension Dynamic shape factor Absorption enhancement

来源：评论

学校读者我要写书评

暂无评论

Predicting Treatment Response of Repetitive Transcranial Magnetic Stimulation in Major Depressive Disorder Using an Explainable Machine Learning Model Based on Electroencephalography and Clinical Features

引用

Biological Psychiatry: Cognitive Neuroscience and Neuroimaging 2025年第6期10卷 656-665页

作者： Zhao, Zongya Ran, Xiangying Niu, Yanxiang Qiu, Mengyue Lv, Shiyang Zhu, Mingjie Wang, Junming Li, Mingcai Gao, Zhixian Wang, Chang Xu, Yongtao Ren, Wu Zhou, Xuezhi Fan, Xiaofeng Song, Jinggui Qi, Mingchao Yu, Yi School of Medical Engineering School of Mathematical Medicine Xinxiang Medical University Xinxiang China Second Affiliated Hospital of Xinxiang Medical University Henan Collaborative Innovation Center of Prevention and Treatment of Mental Disorder Xinxiang China Henan International Joint Laboratory of Neural Information Analysis and Drug Intelligent Design Xinxiang China Henan Engineering Research Center of Medical Virtual Reality Intelligent Sensing Feedback Xinxiang China Henan Engineering Research Center of Physical Diagnostics and Treatment Technology for Mental and Neurological Diseases Henan China Engineering Technology Research Center of Neurosense and Control of Henan Province Xinxiang China Institute of Disaster and Emergency Medicine Tianjin University Tianjin China

Major depressive disorder (MDD) is highly heterogeneous in response to repetitive transcranial magnetic stimulation (rTMS), and identifying predictive biomarkers is essential for personalized treatment. However, most prior research studies have used either electroencephalography (EEG) or clinical features, lack interpretability, or have small sample sizes. This study included 74 patients with MDD who responded (responders) and 43 patients with MDD who did not respond (nonresponders) to rTMS. Eight baseline EEG metrics and clinical features were sent to 7 machine learning models to classify responders and nonresponders. Shapley additive explanations (SHAP) was used to interpret feature contributions. Combining phase locking value and clinical features with support vector machine achieved optimal classification performance (accuracy = 97.33%). SHAP revealed that delta and beta band functional connectivity (F3-P7, F3-P4, P3-P8, T7-Cz) significantly influenced predictions and differed between groups. This study developed an explainable predictive framework to predict rTMS response in MDD, enhancing the accuracy of rTMS response prediction and supporting personalized treatment in MDD. © 2025 Society of Biological Psychiatry

关键词： Biomarkers Machine learning Major depressive disorder Predicting treatment response rTMS

来源：评论

学校读者我要写书评

暂无评论

Experimental analysis on mechanical properties of sea sand geopolymer recycled aggregate concrete

引用

Construction and Building Materials 2024年 457卷

作者： Chen, Yuliang Zhang, Zihong Liu, Zhihua Ye, Peihuan School of Civil Engineering and Architecture Guangxi University of Science and Technology Liuzhou545006 China Guangxi Engineering Research Center for Safety Prevention and Control of Assembly Structure Guangxi University of Science and Technology Liuzhou545006 China Key Laboratory of Disaster prevention & Mitigation and Prestress Technology of Guangxi Colleges and Universities Liuzhou545006 China

Traditional silicate concrete has the problem of high CO2 emissions, in the context of the large-scale use of portland concrete, aggregate resources are increasingly scarce, which poses a non-negligible threat to the natural environment. Therefore, to cope with the influence of traditional silicate concrete on the natural environment, a new type of sea sand geopolymer recycle aggregate concrete (SGRAC) was prepared by replacing river sand with sea sand and using recycled aggregate instead of natural aggregate. In this study, a total of 120 test blocks were designed. Firstly, the mechanical properties of geoplymer recycle aggregate concrete (GRAC) and SGRAC under different slag substitution rates were analyzed from the perspective of compressive strength and microstructure. In addition, the mechanical properties of SGRAC under different slag substitution rates and NaOH solution concentrations were further studied. Finally, the strength conversion formula of SGRAC is *** results show that the compressive strength of SGRAC is 7.24 % higher than that of GRAC, and the activation degree of the two is consistent under different dosage. The influence of slag substitution rate and NaOH solution concentration on the mechanical properties of SGRAC is different. The correlation coefficient of slag substitution rate is lower, and its comprehensive mechanical properties are the best at 10 mol/L-60 %. This study lays a theoretical foundation and experimental basis for the subsequent research and application of SGRAC, and the technology helps to reduce CO2 emissions during construction engineering and promotes the sustainable development of the natural environment on which human beings depend. © 2024 Elsevier Ltd

关键词： Fly ash

来源：评论

学校读者我要写书评

暂无评论

Viability And Experimental Study Of Sustainable Steel-Concrete Composite Beams With Novel Demountable Shear Connections Under Positive Bending Moments

SSRN

引用

SSRN 2024年

作者： Xiong, Liquan Liu, Yuguo Chen, Xiaojian Pan, Xingyue Wang, Xinyong Luo, Qiang Department of Civil Engineering Chongqing Three Gorges University Wanzhou Chongqing 404120 China Chongqing Three Gorges Reservoir Bank Slope and Engineering Structure Disaster Prevention and Control ngineering Technology Research Center Wanzhou Chongqing 404120 China

The sustainable steel-concrete composite beams can solve the problem of construction and demolition waste and also hence the reuse or recycling of structural components at the end of its service life to realize the sustainability of a building. Three steel–concrete composite beams with or without demountable shear connectors were constructed and tested to evaluate their flexural and demountable behavior under two-point loading. This paper first presents the structural configuration and mechanical properties of sustainable steel-concrete composite beams with novel demountable shear connections and then nonlinear analysis of this proposed composite beams using the Abaqus software was validated. The effect of different types of demountable connectors for the composite beams on the flexural behavior and deconstructability was performed. Results from this research showed that these composite beams exhibit a flexure-shear or flexural behavior, presenting the typical failure modes of yielding of steel beam, slab concrete split or concrete crushing of plug. Compared to that of traditional composite beam with embedded welded bolts, specimens with demountable shear bolts and demountable shear connections experienced reduced initial flexural stiffness (about 29.8% and 37.2%), yield strength (by about 18.3% and 32.1%) and ultimate strength (about 12.9% and 24.9%) due to the relative slip between the steel beam and precast slab, respectively. Whereas the demountable composite beams developed a better deformation capacity and ductility coefficient. Additionally, the composite beams with demountable shear connections can easily allow for easy installing and disassembling at the end of the service life for a building to achieve the reuse or recycle of these structural members and also replacing with new plugs to permit a quick seismic rehabilitation after earthquake. Finally, some suggestions of the sustainable composite beams and demountable shear connections were proposed to prov

关键词： Sustainable development

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：