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跨课程自循环工程实训模式的构建与实践——以钢筋混凝土单梁实验为例

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实验室研究与探索 2024年第9期43卷 177-181页

作者：路韡武红娟苗强强顾皓玮黄洪猛西北民族大学土木工程学院兰州730124

以钢筋混凝土单梁试件为聚焦点,对工程实训课程进行了建设。实训中以项目制布置实训任务,围绕单梁准备、单梁制作、单梁实验、能力拓展、成绩评定等环节进行设计和建设,要求大四学生跨课程应用所学专业知识撰写项目方案,制作、检测、验... 详细信息

以钢筋混凝土单梁试件为聚焦点,对工程实训课程进行了建设。实训中以项目制布置实训任务,围绕单梁准备、单梁制作、单梁实验、能力拓展、成绩评定等环节进行设计和建设,要求大四学生跨课程应用所学专业知识撰写项目方案,制作、检测、验收混凝土单梁,协助教师指导大二学生完成单梁破坏实验。实践证明,该实训模式串联了多门专业课程,使专业知识在实训课程中完成了循环;制作的单梁试件实现了专业内的自循环,节省了实验成本;学生实践能力、团队意识得到了锻炼,对工程流程和施工环境有了切身的体会。

关键词：工程实训课程建设单梁破坏实验跨课程

Observation and research of deep underground multi-physical fields—Huainan–848 m deep experiment

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Science China Earth Sciences 2023年第1期66卷 54-70页

作者： Yun WANG Yaxin YANG Heping SUN Chengliang XIE Qisheng ZHANG Xiaoming CUI Chang CHEN Yongsheng HE qiangqiang miao Chaomin MU Lianghui GUO Jiwen TENG School of Geophysics and Information Technology China University of GeosciencesBeijing 100083China School of Geophysics and Measurement-control Technology East China University of TechnologyNanchang 330013China Innovation Academy for Precision Measurement Science and Technology Chinese Academy of SciencesWuhan 430077China Institution of Engineering Protection IDEAMSPLALuoyang 471023China State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines Anhui University of Science and TechnologyHuainan 232001China Institute of Geochemistry Chinese Academy of SciencesGuiyang 550081China

Compared with the surface,the deep environment has the advantages of allowing“super-quiet and ultra-clean”-geophysical field observation with low vibration noise and little electromagnetic interference,which are conducive to the realization of long-term and high-precision observation of multi-physical fields,thus enabling the solution of a series of geoscience *** the Panyidong Coal Mine,where there are extensive underground tunnels at the depth of 848 m below sea level,we carried out the first deep-underground geophysical observations,including radioactivity,gravity,magnetic,magnetotelluric,background vibration and six-component seismic *** concluded from these measurements that(1)the background of deep subsurface gravity noise in the long-period frequency band less than 2 Hz is nearly two orders of magnitude weaker than that in the surface observation environment;(2)the underground electric field is obviously weaker than the surface electric field,and the relatively high frequency of the underground field,greater than 1 Hz,is more than two orders of magnitude weaker than that of the surface electric field;the east-west magnetic field underground is approximately the same as that at the surface;the relatively high-frequency north-south magnetic field underground,below 10 Hz,is at least one order of magnitude lower than that at the surface,showing that the underground has a clean electromagnetic environment;(3)in addition to the highfrequency and single-frequency noises introduced by underground human activities,the deep underground space has a significantly lower background vibration noise than the surface,which is very beneficial to the detection of weak earthquake and gravity signals;and(4)the underground roadway support system built with ferromagnetic material interferes the geomagnetic *** also found that for deep observation in the“ultra-quiet and ultra-clean”environment,the existing geophysical equipment and observation technology hav

关键词： Multi-physical fields Radioactivity Gravity Geomagnetic Electromagnetic Earthquake Observations deep underground

基于图像质量和注意力的宫腔镜视频关键帧提取

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激光与光电子学进展 2019年第6期56卷 122-128页

作者：苗强强武汉理工大学信息工程学院湖北武汉430070

为解决传统方法中由注意力曲线等长分段导致的精确率偏低的问题,提出了基于图像质量曲线提取关键视频段的方法,从各段内选取注意力值最高的帧作为关键帧。针对本地数据库进行视频关键帧提取,精确率为52.94%,F值为62.77%,分别比Muhammad... 详细信息

为解决传统方法中由注意力曲线等长分段导致的精确率偏低的问题,提出了基于图像质量曲线提取关键视频段的方法,从各段内选取注意力值最高的帧作为关键帧。针对本地数据库进行视频关键帧提取,精确率为52.94%,F值为62.77%,分别比Muhammad的方法提高了5.23%和2.65%。

关键词：图像处理宫腔镜视频摘要注意力模型图像质量评估图像锐利度

Effects of Co-Firing Biomass and Pulverized Coal on NO Reduction in Cement Precalciner

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Journal of Thermal Science 2024年第2期33卷 751-760页

作者： LI Pengpeng REN qiangqiang LYU Qinggang WANG Mingyue School of Energy Power and Mechanical Engineering North China Electric Power UniversityBeijing102206China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China

With increased awareness of the large-scale CO_(2) emissions from the cement industry,there has been growing focus on greenhouse gas reduction *** all these strategies,fuel substitution using biomass fuel is extensively used to achieve CO_(2) zero-emission in cement *** to the avoidable high-temperature-generated thermal nitrogen oxides during cement production,research on the impact of biomass application on nitrogen oxide emissions shall be carried *** types of biomass fuel and bituminous coal were used to investigate the NO reduction characteristics under different O_(2) concentrations on experimental *** was found that the change in oxygen concentration from 9% to 1% increased the reaction time in the reactor from 555 s to 1425 s,which means the increase in oxygen concentration can lead to shorter reaction time,and correspondingly,the existing time of nitric oxide in the flue gas is also shortened,but the peak value of nitric oxide rises,during the process of O_(2) concentration changing from 1% to 9%,the peak NO concentration in the flue gas increased from 5.4×10^(-5) to 1.05×10^(-4).An increase in O_(2) concentration greatly reduces the total reduction of NO and the minimum change in NO *** peak NO concentration during the combustion process of corn stalk is 4.56×10^(-4),which is approximately 7 times higher than that of coal,and it is caused by the high amount of N in corn *** addition of raw meal has an inhibitory effect on the reduction of NO:after adding raw meal,the effective reduction time of NO by fuel decreased by about 20%,but adding raw meal raises CO_(2) concentration of fuel gas in the early stage of reaction.

关键词： cement precalciner biomass fuel coal NO reduction co-firing

Numerical study on the use of soft material walls to enhance seismic performance of an existing tunnel

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Underground Space 2024年第2期15卷 90-112页

作者： qiangqiang Sun Menghao Hou Daniel Dias Institute of Geotechnical Engineering College of Civil Engineering and ArchitectureHebei UniversityBaoding 071002China Laboratory 3SR CNRS UMR 5521Grenoble Alpes UniversityGrenoble 38000France

Seismic risk is one of the biggest challenges for tunnel safety,and several mitigation techniques have been proposed to enhance the seismic performance of existing *** paper aims to investigate the effectiveness of an innovative approach for reducing the seismic risk of existing tunnels by using soft material walls(SMW)symmetrically installed in the surrounding *** investigation is performed with a two-dimensional numerical model and the effectiveness of SMW in mitigating the seismic-induced lining forces is quantitatively evaluated by reduction *** influences of nonlinear properties of soil,SMW and tunnel lining on the isolation effectiveness are also *** parametric studies show that the computed reduction ratio is strongly affected by the modulus ratio between the SMW and the soil,the wall geometric parameter,and the flexibility *** is more effective for the thick and soft isolation walls that are inserted near a stiff tunnel in the soft *** tunnel seismic response can be reduced by up to 50%for the scenarios ***,the parametric study identifies an optimum normalized depth of SMW and recommends a relation between the maximum isolation effect and the flexibility ***,simple charts are suggested in this work for estimating the isolation effect in specific conditions of the soil and the *** these lines,the results of this work may be used in the seismic retrofitting of an existing tunnel,aiding the preliminary design of the isolation walls.

关键词： Tunnels Earthquakes Seismic analysis Isolation walls Soft material

Modification of Melting Combustion Kinetic Model of Fine Ash from Entrained-Flow Gasifier

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Journal of Thermal Science 2024年第1期33卷 300-310页

作者： WANG Wenyu LI Wei LU Yu REN qiangqiang LYU Qinggang Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Dalian National Laboratory for Clean Energy Chinese Academy of SciencesDalian 116023China

Coal gasification technology is a prominent technology in the coal chemical industry and serves as the fundamental basis for various process industries,including coal-based chemicals,coal-based liquid fuels,Integrated Gasification Combined Cycle(IGCC) power generation,multi-generation systems,hydrogen production,and fuel *** gasification process generates significant quantities of ash residue,with annual emissions exceeding tens of millions of tons and accumulation reaching hundreds of millions of ***,there is an urgent need to investigate methods for its *** combustion of gasified fine ash(GFA) was conducted in a tube furnace,and the conventional shrinking core model was modified to accurately predict the combustion behaviors at different temperatures(900℃-1500℃).We divided the reaction temperatures into three ranges,which is defined as unmelted combustion(TFT) and mixed combustion(DTFT),the surface ash of GFA grains fell off,and the residual carbon and gas-phase reactants were nearly no longer affected by the diffusion resistance,thus significantly accelerated the reaction of internal residual *** order to predict the melt combustion process more accurately,the time term of the shrinkage core model(SCM) is modified,and the effective diffusion coefficient of T>FT is defined.

关键词： fine ash melting combustion kinetic model combustion characteristics

Evolution Mechanism of Carbon Covalent Bond during Coal Activation Using Mixed Atmosphere of H_(2)O and CO_(2)

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Journal of Thermal Science 2024年第5期33卷 1961-1973页

作者： WANG Mingyue ZHANG Siyuan HAN Shaobo ZHANG Chi REN qiangqiang Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Coal Conversion Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China

Adequate destruction of the aromatic structure in coal is key to further reducing the emission of *** this research,activation reactions of Shenmu coal powder were carried out in a vertical tube *** study investigated the evolution mechanism of carbon covalent bonds during the activation process by altering the ratio of H_(2)O to CO_(2)in the activation *** theoretical validation was conducted through density functional *** two gas molecules follow different pathways to increase the reactivity of ***_(2)mainly participates in the cross-linking reaction by intensifying branching,while H_(2)O and char have lower adsorption energy barriers and are more likely to generate oxygen-containing functional *** molecules partially compete for active sites in a mixed gas atmosphere,but there is a synergism between the two *** synergism can be attributed to two *** inclusion of H_(2)O mitigates the generation of five-membered rings to a limited extent,while concurrently enhances the development of oxygen-containing functional *** oxygen-containing functional groups can effectively diminish the adsorption energy barrier associated with the interaction between gas molecules and char,consequently leading to a reduction in the energy demand for subsequent bond cleavage.

关键词： activation reaction carbon structure char CO_(2)/H_(2)O atmosphere density functional theory

Steady-state Voltage Security-constrained Optimal Frequency Control for Weak HVDC Sending-end AC Power Systems

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 658-669页

作者： qiangqiang Wang Liangzhong Yao Jian Xu Yuping Zheng Wei Li Wei Wang School of Electrical Engineering and Automation Wuhan UniversityWuhan 430072China Hubei Engineering and Technology Research Center for AC/DC Intelligent Distribution Network(Wuhan University) Wuhan 430072China State Key Laboratory of Smart Grid Protection and Control NARI Group Corporation(State Grid Electric Power Research Institute)Nanjing 211106China

Due to the fact that a high share of renewable energy sources(RESs)are connected to high-voltage direct current(HVDC)sending-end AC power systems,the voltage and frequency regulation capabilities of HVDC sending-end AC power systems have *** has resulted in potential system operating problems such as overvoltage and overfrequency,which occur simultaneously when block faults exist in the HVDC *** this study,a steady-state voltage security-constrained optimal frequency control method for weak HVDC sending-end AC power systems is *** integrated virtual inertia control of RESs is employed for system frequency *** dynamic reactive power compensation devices are utilized to control the voltage of all nodes meet voltage security ***,an optimization model that simultaneously considers the frequency and steady-state voltage security constraints for weak HVDC sending-end AC power systems is *** optimal control scheme with the minimum total cost of generation tripping and additional dynamic reactive power compensation required is obtained through the optimization *** are conducted on a modified IEEE 9-bus test system and practical Qing-Yu line commutated converter based HVDC(LCC-HVDC)sending-end AC power system to verify the effectiveness of the proposed method.

关键词： Renewable energy source(RES) high-voltage direct current(HVDC) AC power system optimal frequency control steady-state voltage security dynamic reactive power compensation

Characterization of physicochemical and immunogenic properties of allergenic proteins altered by food processing:a review

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Food Science and Human Wellness 2024年第3期13卷 1135-1151页

作者： Enning Zhou qiangqiang Li Dan Zhu Gang Chen Liming Wu Institute of Apicultural Research Chinese Academy of Agricultural SciencesBeijing 100093China Department of Food Science University of OtagoDunedin 9016New Zealand School of Food and Health Beijing Technology and Business UniversityBeijing 100048China

Food allergens are mainly naturally-occurring proteins with immunoglobulin E(IgE)-binding *** the structural and immunogenic characteristics of allergenic proteins is essential in assessing whether and how food processing techniques reduce *** here discuss the impacts of food processing technologies on the modification of physicochemical,structural,and immunogenic properties of allergenic *** techniques for characterizing changes in these properties of food allergens are *** processing helps to reduce allergenicity by aggregating or denaturing proteins,which masks,modifies,or destroys antigenic epitopes,whereas,it cannot eliminate allergenicity completely,and sometimes even improves allergenicity by exposing new ***,most food processing techniques have been tested on purified food allergens rather than food products due to potential interference of other food *** provide guidance for further development of processing operations that can decrease the allergenicity of allergenic food proteins without negatively impacting the nutritional profile.

关键词： Food allergens Protein structural characterization Immunogenicity evaluation Food processing modification