检索结果-南通市图书馆

Science China Chemistry 2025年

作者： haoyu zhang Yuhang Li Yu Nie Xinyu Dou Haodong Ji Xin Tan Jinhua Ye Tao Yu School of Chemical Engineering and Technology Tianjin University Eco-environment and Resource Efficiency Research Laboratory School of Environment and Energy Peking University Shenzhen Graduate School School of Environmental Science and Engineering Tianjin University Advanced Catalytic Materials Research Center School of Materials Science and Engineering Tianjin University Research Center for Solar Driven Carbon Neutrality Hebei University

Photothermal catalytic CO2hydrogenation is an effective means of utilizing carbon ***,it is severely limited in terms of kinetics and ***,it is necessary to meticulously design catalysts to solve this ***,a sandwich structured NiO@InNi/In2O3is designed to intrinsically regulate the direction of photogenerated carriers transfer,resulting in a CO yield of 42.97 mmol g-1h-1(1290.3μmol h-1) with a selectivity near to 100%.InNi alloy favors the collection of photogenerated carriers by the parallel way and enhancement of the adsorption and activation of *** grown on the surface of InNi alloy not only improves the adsorption of H2and provides sufficient H+for the reaction,but also makes InNi alloy more stable during the reaction *** photothermal effect caused by In2O3accelerates the transfer of photogenerated carriers and increases the surface temperature of the catalyst,thereby synergistically promoting the reaction from a kinetic *** work ameliorates the kinetic and thermodynamic limitations of the photothermal catalytic CO2hydrogenation process through rationally designing the electron transfer direction of the sandwich structured catalysts to parallel way.

关键词：

职业院校课程思政建设:价值内涵、现实困境与突破路径

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

职业技术教育 2025年第2期46卷 24-28页

作者：付国华张浩瑜吉林工程技术师范学院学生工作部长春130052 吉林建筑大学

全面推进课程思政建设是落实立德树人这一根本任务的重要举措,有利于促进学生全面发展、提升学生职业素养、培养学生技术精神、提升学生社会责任感。当前,职业院校课程思政建设存在教学资源不足与更新滞后、教师思政素养不高、学生参与... 详细信息

全面推进课程思政建设是落实立德树人这一根本任务的重要举措,有利于促进学生全面发展、提升学生职业素养、培养学生技术精神、提升学生社会责任感。当前,职业院校课程思政建设存在教学资源不足与更新滞后、教师思政素养不高、学生参与度较低、缺乏创新性和特色、机制不健全等困境。未来,职业院校需要通过优化资源配置、创新课程设计、激活内生动力、提升教师素养、健全评价机制来深化课程思政建设,提升人才培养成效。

关键词：职业院校课程思政思政课程立德树人

α相对亚稳β钛合金Ti-5.5Cr-5Al-4Mo-3Nb-2Zr在3.5%NaCl溶液中应力腐蚀行为的影响

在线全文

学校读者我要写书评

暂无评论

稀有金属材料与工程 2025年第1期54卷 209-217页

作者：刘璇张浩宇王圣元周舸程军陈立佳沈阳工业大学辽宁沈阳110870 西北有色金属研究院陕西西安710016

设计了一种亚稳β钛合金Ti-5.5Cr-5Al-4Mo-3Nb-2Zr,利用不同热处理方式获得3种具有不同α相的微观组织,利用SEM、TEM、电化学实验及慢应变速率拉伸实验研究α相对该合金应力腐蚀行为的影响,结果表明:经过650℃/6 h时效处理次生α_s相粗... 详细信息

设计了一种亚稳β钛合金Ti-5.5Cr-5Al-4Mo-3Nb-2Zr,利用不同热处理方式获得3种具有不同α相的微观组织,利用SEM、TEM、电化学实验及慢应变速率拉伸实验研究α相对该合金应力腐蚀行为的影响,结果表明:经过650℃/6 h时效处理次生α_s相粗化(组织编号:M1),经过两相区的790℃/0.5 h固溶处理形成粗大的初生α_p相(组织编号:M2),经过790℃/0.5 h固溶处理与650℃/6 h时效处理同时存在粗大的初生α_(p)相、细小的次生α_(s)相(组织编号:M3)。电化学实验结果表明M3的自腐蚀电流密度相对最低为1.10×10^(-8)A/cm^(2),极化电阻相对最高为2.30×10^(10)Ω·cm^(2),其耐腐蚀性能最好,其次为M2,M1最差。慢应变速率拉伸实验结果表明M3具有相对最低的应力腐蚀敏感性指数为5.0%,其应力腐蚀开裂敏感性相对最低。该合金的应力腐蚀开裂机制为氢吸附促进位错运动和氢促进局部塑性变形的相互作用。

关键词：亚稳β钛合金应力腐蚀 α相电化学实验慢应变速率拉伸实验

Neural Liénard system: learning periodic manipulation skills through dynamical systems

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2024年第12期67卷 256-271页

作者： haoyu zhang Long CHENG Yu zhang Yifan WANG School of Artificial Intelligence University of Chinese Academy of Sciences State Key Laboratory for Multi-modal Artificial Intelligence Systems Institute of AutomationChinese Academy of Sciences

Learning from demonstrations provides effective methods for teaching robot manipulation ***, capturing periodic manipulation skills remains challenging with the current techniques. To address this gap, we introduce the neural Liénard system(neural LS), a novel neural network framework that utilizes Liénard-type differential equations to create dynamical systems with stable and distinct limit cycles. We also introduce an innovative technique, which not only manages periodic trajectories across various dimensions but also handles trajectories with intersections, enhancing the capability of the robot for complex tasks. We provide a thorough theoretical analysis of neural LS, focusing on its stability and representational *** evaluations show that neural LS achieves superior performance in modeling complex limit cycles,surpassing the existing methods. We particularly emphasize its effectiveness in handling high-dimensional periodic motions and trajectories with intersections. In addition, we explore the adaptability and robustness of neural LS. A practical application involving the Franka Emika robot in a drawing task further demonstrates the real-world utility of neural LS, confirming its effectiveness and potential to equip robots with advanced periodic manipulation skills.

关键词： learning from demonstrations stable dynamical system periodic motions

同方期刊数据库

在线全文

学校读者我要写书评

暂无评论

某海岛地下水封洞库水封可靠性研究

科学技术创新 2025年第5期 134-137页

作者：张皓宇叶林米中国地质大学(北京)工程技术学院北京浙江省工程物探勘察设计院有限公司浙江杭州

面对国内日益严峻的能源安全形式,地下水封洞库以其诸多优点,成为目前大规模储油的首选方式,为提高我国石油储备量及海岛资源利用率,在海岛环境下建造地下水封油库成为一种新的思路。本文依托某海岛地下水封油库项目,基于流固耦合理论,... 详细信息

面对国内日益严峻的能源安全形式,地下水封洞库以其诸多优点,成为目前大规模储油的首选方式,为提高我国石油储备量及海岛资源利用率,在海岛环境下建造地下水封油库成为一种新的思路。本文依托某海岛地下水封油库项目,基于流固耦合理论,利用COMSOL Multiphysics有限元软件对海岛环境地下水封油库的水封性进行分析。研究表明:在海岛环境建造地下水封洞库如果不设置水幕系统,洞库上方地下水位线形成明显的降落漏斗,部分洞室的顶部会发生疏干现象,水封失效,无法满足水封可靠性要求;在设置水平水幕系统工况,水封洞库上方地下水可形成较厚的地下水覆盖层,满足洞库设计规范水封可靠性的要求。该成果为海岛环境下建造地下水封洞库水封安全评价提供了一定的理论参考。

关键词：地下水封洞库数值模拟水封可靠性

Physics-informed machine learning model for prediction of ground reflected wave peak overpressure

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第11期41卷 119-133页

作者： haoyu zhang Yuxin Xu Lihan Xiao Canjie Zhen State Key Lab of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China Chongqing Innovation Center Beijing Institute of TechnologyChongqing 404100China Tangshan Research Institute Beijing Institute of TechnologyTangshan 442000China Shandong Special Industry Group Co.Ltd. Zibo 255000China

The accurate prediction of peak overpressure of explosion shockwaves is significant in fields such as explosion hazard assessment and structural protection, where explosion shockwaves serve as typical destructive elements. Aiming at the problem of insufficient accuracy of the existing physical models for predicting the peak overpressure of ground reflected waves, two physics-informed machine learning models are constructed. The results demonstrate that the machine learning models, which incorporate physical information by predicting the deviation between the physical model and actual values and adding a physical loss term in the loss function, can accurately predict both the training and out-oftraining dataset. Compared to existing physical models, the average relative error in the predicted training domain is reduced from 17.459%-48.588% to 2%, and the proportion of average relative error less than 20% increased from 0% to 59.4% to more than 99%. In addition, the relative average error outside the prediction training set range is reduced from 14.496%-29.389% to 5%, and the proportion of relative average error less than 20% increased from 0% to 71.39% to more than 99%. The inclusion of a physical loss term enforcing monotonicity in the loss function effectively improves the extrapolation performance of machine learning. The findings of this study provide valuable reference for explosion hazard assessment and anti-explosion structural design in various fields.

关键词： Blast shock wave Peak overpressure Machine learning Physics-informed machine learning

Dihedral influence on lateral–directional dynamic stability on large aspect ratio tailless flying wing aircraft

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2014年第5期27卷 1149-1155页

作者： Song Lei Yang Hua zhang Yang zhang haoyu Huang Jun School of Aeronautic Science and Engineering Beihang University AVIC The First Aircraft Institute

The influence of dihedral layout on lateral–directional dynamic stability of the tailless flying wing aircraft is discussed in this paper. A tailless flying wing aircraft with a large aspect ratio is selected as the object of study, and the dihedral angle along the spanwise sections is divided into three segments. The influence of dihedral layouts is studied. Based on the stability derivatives calculated by the vortex lattice method code, the linearized small-disturbance equations of the lateral modes are used to determine the mode dynamic characteristics. By comparing 7056 configurations with different dihedral angle layouts, two groups of stability optimized dihedral layout concepts are created. Flight quality close to Level 2 requirements is achieved in these optimized concepts without any electric stability augmentation system.

关键词： Dihedral angle Flying wing Optimization Stability Tailless

Seismic damage to structures in the Ms6.5 Ludian earthquake

在线全文

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibration 2016年第1期15卷 173-186页

作者： Chen Hao Xie Quancai Dai Boyang zhang haoyu Chen Hongfu Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering Mechanics CEA Harbin 150080 China Earthquake Administration of Yunnan Province Kunming 650224 China

On 3 August 2014, the Ludian earthquake struck northwest Yunnan Province with a surface wave magnitude of 6.5. This moderate earthquake unexpectedly caused high fatalities and great economic loss. Four strong motion stations were located in the areas with intensity V, VI, VII and IX, near the epicentre. The characteristics of the ground motion are discussed herein, including 1） ground motion was strong at a period of less than 1.4 s, which covered the natural vibration period of a large number of structures; and 2） the release energy was concentrated geographically. Based on materials collected during emergency building inspections, the damage patterns of adobe, masonry, timber frame and reinforced concrete （RC） frame structures in areas with different intensities are summarised. Earthquake damage matrices of local buildings are also given for fragility evaluation and earthquake damage prediction. It is found that the collapse ratios of RC frame and confined masonry structures based on the new design code are significantly lower than non-seismic buildings. However, the RC frame structures still failed to achieve the ＇strong column, weak beam＇ design target. Traditional timber frame structures with a light infill wall showed good aseismic performance.

关键词： Ludian earthquake investigations of seismic damage masonry structure RC frame timber flame adobehouse

Field investigation on severely damaged aseismic buildings in 2014 Ludian earthquake

在线全文

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibration 2015年第1期14卷 169-176页

作者： Lin Xuchuan zhang haoyu Chen Hongfu Chen Hao Lin Junqi Institute of Engineering Mechanics China Earthquake Administration Key Laboratory of Earthquake Engineering and Engineering Vibration China Earthquake Administration

The 2014 magnitude 6.5 Ludian earthquake caused a death toll of 617, many landslides and tens of thousands of collapsed buildings. A field investigation to evaluate the damage to buildings was carried out immediately after the occurrence of the earthquake. Severely damaged aseismic buildings, which were basically observed in the downtown of Longtoushan Town, were carefully examined one by one with the aim to improve design codes. This paper summarizes the damage observed to the investigated aseismic buildings in both the structural and local levels. A common failure mode was observed that most of the aseismic buildings, such as RC frame structures and confined masonry structures, were similarly destroyed by severe damage or complete collapse of the first story. The related strong ground motion, which was recorded at the nearby station, had a short duration of less than 20 s but a very large PGA up to 1.0 g. The RC frames based on the new design codes still failed to achieve the design target for ＂strong column, weak beam＂. Typical local failure details, which were related to the interaction between RC columns and infill walls and between constructional columns and masonry walls, are summarized with preliminary analyses.

关键词： Ludian earthquake field investigation aseismic buildings structural collapse local failure

Highly selective photocatalytic CO_(2) reduction to ethylene in pure water by Nb_(2)O_(5) nanoparticles with enriched surface –OH groups under simulated solar illumination

在线全文

学校读者我要写书评

暂无评论

Journal of Advanced Ceramics 2023年第8期12卷 1641-1654页

作者： haoyu zhang Shuang Gao Haitao Guan Weiyi Yang Qi Li Key Laboratory of Advanced Technologies of Materials Ministry of EducationSchool of Materials Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031China

Photocatalytic CO_(2) reduction to valuable chemical compounds could be a promising approach for carbon-neutral *** this work,a simple and robust thermal decomposition process was developed with ammonium carbonate((NH4)2CO3)as both precipitation agent and sacrificial template to produce fine Nb_(2)O_(5) nanoparticles with the rich existence of surface hydroxyl(–OH)*** was found by density functional theory(DFT)calculations and experiments that the rich existence of the surface–OH groups enhanced the adsorption of both reactants(CO_(2) and H_(2)O molecules)for the photocatalytic CO_(2) reduction on these fine Nb_(2)O_(5) nanoparticles,and the highly selective conversion of CO_(2) to the high-value chemical compound of ethylene(C_(2)H_(4),~68μmol·g^(−1)·h^(−1) with~100%product selectivity)was achieved under simulated solar illumination without usage of any sacrificial agents or noble metal *** synthesis process may also be readily applied as a surface engineering method to enrich the existence of the surface–OH groups on various metal oxide-based photocatalysts for a broad range of technical applications.

关键词： photocatalytic CO_(2)reduction niobium oxide nanoparticles thermal decomposition surface hydroxyl(-OH)groups simulated solar illumination