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基于能量法的混凝土损伤断裂耦合分析

浙江水利水电学院学报 2018年第4期30卷 46-50页

作者：何晓壮邓爱民杨建凤上海千年城市规划工程设计股份有限公司上海201108 河海大学工程力学系江苏南京210098 嘉兴市财政局浙江嘉兴314000

混凝土结构的破坏过程,实际上是损伤和断裂交织发展的耦合过程,其实质是材料的逐渐弱化,并伴随着能量的耗散,从能量平衡的角度判定混凝土裂缝的稳定性是一个常用的方法.结合断裂力学和损伤力学,针对I型张开型裂缝,推导了裂缝尖端附近损... 详细信息

混凝土结构的破坏过程,实际上是损伤和断裂交织发展的耦合过程,其实质是材料的逐渐弱化,并伴随着能量的耗散,从能量平衡的角度判定混凝土裂缝的稳定性是一个常用的方法.结合断裂力学和损伤力学,针对I型张开型裂缝,推导了裂缝尖端附近损伤断裂耦合参数——损伤型能量释放率计算公式.基于线性渐进叠加假定,采用数值计算的方法模拟了4种不同尺寸三点弯曲梁试件的断裂破坏过程,并通过计算得到了断裂能量释放率、损伤能量释放率和损伤断裂能量释放率.通过对断裂能量释放率、损伤能量释放率和损伤断裂能量释放率随裂缝扩展变化规律的对比分析,给出了裂缝失稳扩展时对应的损伤断裂能量释放率.

关键词：能量法损伤断裂耦合损伤断裂能量释放率

Effect of Polyacrylamide Application on Runoff,Erosion,and Soil Nutrient Loss Under Simulated Rainfall

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Pedosphere 2011年第5期21卷 628-638页

作者： WANG ai-Ping LI Fa-Hu yang Sheng-min Inner Mongolia Coal mine Design and Research Institute No. 55 Xinhua Road Hohhot 010010 (China) College of Water Conservancy and Civil Engineering China Agricultural University No. 17 Qinghua East Avenue Haidian District Beijing 100083 (China) State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau No. 26 Xinong Road Yangling 712100 (China) Beijing Vocational College of Agriculture No. 5 Daotiannanli Changyang Town Beijing 102442(China)

Soil erosion affects soil productivity and environmental quality.A laboratory research experiment under simulated heavy rainfall with tap water was conducted to investigate the effects of anionic polyacrylamide(PAM) application rates(0,0.5,1.0,and 2.0 g m-2) and molecular weights(12 and 18 Mg mol-1) on runoff,soil erosion,and soil nutrient loss at a slope of 5°.The results showed the two lower rates of PAM application decreased runoff while the highest rate increased runoff as compared with the *** concentration and soil mass loss increased significantly with the increasing PAM application *** with the control,PAM application decreased K+,NH4+,and NO3-concentrations in sediment and K+ and NH+4 concentrations in runoff,but significantly increased the mass losses of K+,NH4+,and NO-3 over soil surface except for the NH4+ at PAM application rate lower than 1.0 g *** application decreased the proportion of K+ loss with runoff to its total mass loss over soil surface from 60.1% to 16.4%.However,it did not affect the NH4+ and NO3-losses with runoff,and more than 86% of them were lost with runoff.A higher PAM molecular weight resulted in less soil erosion and K+ mass loss but had little effect on runoff and NH+4 and *** application did not prevent soil erosion and the mass losses of K+ and NO3-under experimental conditions.

关键词： application rate mass loss molecular weight nutrient concentration sediment concentration

A graph autoencoder network to measure the geometric similarity of drainage networks in scaling transformation

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International Journal of Digital Earth 2023年第1期16卷 1828-1852页

作者： Huafei Yu Tinghua ai min yang Weiming Huang Lars Harrie School of Resource and Environmental Sciences Wuhan UniversityWuhanPeople’s Republic of China Department of Physical Geography and Ecosystem Science Lund UniversityLundSweden School of Computer Science and Engineering Nanyang Technological UniversitySingaporeSingapore

Similarity measurement has been a prevailing research topic geographic information *** similarity measurement inin scaling transformation(GSM_ST)is critical to ensure spatial data quality while balancing detailed information with distinctive ***,GSM_ST is an uncertain problem due to subjective spatial cognition,global and local concerns,and geometric *** rule-based methods considering multiple consistent conditions require subjective adjustments to characteristics and weights,leading to poor robustness in addressing GSM_*** study proposes an unsupervised representation learning framework for automated GSM_ST,using a Graph Autoencoder Network(GAE)and drainage networks as an *** framework involves constructing a drainage graph,designing the GAE architecture for GSM_ST,and using Cosine similarity to measure similarity based on the GAE-derived drainage embeddings in different *** perform extensive experiments and compare methods across 71 drainage networks duringfive scaling *** results show that the proposed GAE method outperforms other methods with a satisfaction ratio of around 88%and has strong ***,our proposed method also can be applied to other scenarios,such as measuring similarity between geographical entities at different times and data from different datasets.

关键词： Geometric similarity measurement drainage network scaling transformation graph autoencoder network

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高温环境对激光火工品发火性能的影响

火工品 2025年第1期 32-36页

作者：鱼小港贺爱锋陈建华郑薇杨安民祝捷李敏杰陕西应用物理化学研究所瞬态化学效应与控制全国重点实验室陕西西安710061 中北大学环境与安全工程学院山西太原030051

为了研究高温环境对激光火工品发火性能的影响,建立了激光火工品的热力场仿真模型,并搭建光学测试系统,探究了激光火工品自聚焦透镜在100℃高温下的激光光斑尺寸变化。仿真结果表明:高温环境下自聚焦透镜长度产生92.4μm的变形量,导致... 详细信息

为了研究高温环境对激光火工品发火性能的影响,建立了激光火工品的热力场仿真模型,并搭建光学测试系统,探究了激光火工品自聚焦透镜在100℃高温下的激光光斑尺寸变化。仿真结果表明:高温环境下自聚焦透镜长度产生92.4μm的变形量,导致激光光斑尺寸从94μm增大至150μm;试验结果表明:高温环境下激光火工品输出光斑在243~272μm之间变化,自聚焦透镜变形量的增大导致激光火工品的刺激功率密度降低、作用时间超差。研究表明自聚焦透镜变形降低了激光火工品的发火可靠性。

关键词：激光火工品自聚焦透镜激光光斑发火可靠性高温环境

Molybdenum alloying in high-performance flat-rolled steel grades

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Advances in Manufacturing 2020年第1期8卷 15-34页

作者： Pello Uranga Cheng-Jia Shang Takehide Senuma Jer-Ren yang ai-min Guo Hardy Mohrbacher CEIT and TECNUN University of NavarraSan SebastianSpain Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083People's Republic of China Graduate School for Nature Science Okayama UniversityOkayamaJapan Institute of Materials Science and Engineering Taiwan UniversityTaipeiTaiwanPeople's Republic of China CITIC Metal Beijing 100027People's Republic of China Department of Materials Engineering KU LeuvenLeuven 3001Belgium NiobelCon bvba Schilde 2970Belgium

Considerable progress in developing flat-rolled steel grades has been made by the Chinese steel industry over the recent two *** increasing demand for high-performance products to be used in infrastructural projects as well as in production of consumer and capital goods has been driving this development until *** installation of state-of-the-art steel making and rolling facilities has provided the possibility of processing the most advanced steel *** production of high-performance steel grades relies on specific alloying elements of which molybdenum is one of the most *** is nearly self-sufficient in molybdenum *** paper highlights the potential and advantages of molybdenum alloying over the entire range of flat-rolled steel *** aspects of steel property improvement with respect to particular applications are indicated.

关键词： HSLA steel Quench&tempering Direct quenching Press hardening Quenching&partitioning Precipitation

Contribution of Quark Structure Term in Nucleon Electric and Magnetic Form Factors

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Communications in Theoretical Physics 2004年第5X期42卷 735-738页

作者： WANGHong-min ZHANGBen-ai GraduateSchool theChineseAcademyofEngineeringPhysicsBeijing100088China

The constituent quarks in the nucleon have always been considered as a point-like particle in the relativistic constituent quark model. However its calculation results of GnE agree poorly with the new experimental data. The electromagnetic structure of light front constituent quarks is considered in this paper. We find that the calculation results have good agreement with the new experimental data of GnE after considering the contribution of the quark structure term. This treatment seems to be able to improve the fit to experimental data of Gep/GMp, /Q2F2p/kpF1p,and Gen/GMn as well.

关键词：波形因数相对论夸克模型辐射方程夸克结构核子弹性电磁学

Electric and Magnetic Form Factors of Proton in Relativistic Constituent QuarkModel

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Communications in Theoretical Physics 2004年第3期41卷 425-428页

作者： WANGHong-min ZHANGBen-ai GraduateSchool theChineseAcademyofEngineeringPhysicsBeijing100088China

Based on relativistic constituent quark (RCQ) model, the electric and magnetic form factors are analyzed. The ratio of the two form factors for the proton , which is an image of its charge and magnetization distributions, is calculated in the light-front formulism of RCQ model. Recently, this ratio was measured at the Thomas Jefferson National Accelerator Facility (JLab) using the polarization technique. The new data presented span the range and are well described by a linear Q2 fit. Also, the ratio reaches a constant value while Q2 becomes larger than 2 (GeV)2. Our calculation results are presented and appear to be consistent with the experimental ones.

关键词： form factors relativistic constituent quark model radial function

Simulation and Prediction of Alkalinity in Sintering Process Based on Grey Least Squares Support Vector Machine

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Journal of Iron and Steel Research International 2009年第5期16卷 1-6页

作者： SONG Qiang WANG ai-min Mechanical Engineering Department Anyang Institute of Technology Anyang 455000 Henan China Computer and Information Engineering College Anyang Normal University Anyang 455000 Henan China

The prediction of the alkalinity is difficult during the sintering process. Whether or not the level of the alkalinity of sintering process is successful is directly related to the quality of sinter. There is no very good method for predicting the alkalinity by now owing to the high complexity, high nonlinearity, strong coupling, high time delay, and etc. Therefore, a new technique, the grey squares support machine, was introduced. The grey support vector machine model of the alkalinity enabled the development of new equation and algorithm to predict the alkalinity. During modelling, the fluctuation of data sequence was weakened by the grey theory and the support vector machine was capable of processing nonlinear adaptable information, and the grey support vector machine has a combination of those advantages. The results revealed that the alkalinity of sinter could be accurately predicted using this model by reference to small sample and information. The experimental results showed that the grey support vector machine model was effective and practical owing to the advantages of high precision, less samples required, and simple calculation.

关键词： alkalinity sinter grey least squares support vector machine prediction sintering process grey model

EFFECT OF HYPERCROSSLINKED RESINS SURFACE CHEMISTRY ON THE ADSORPTION OF PHENOL FROM AQUEOUS SOLUTION

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Chinese Journal of Polymer Science 2006年第6期24卷 585-591页

作者： Guan-hua Meng ai-min Li Wei-ben yang Fu-qiang Liu Quan-xing Zhang State Key Laboratory of Pollution Control and Resources Reuse School of the Environment Nanjing University Nanjing 210093 China Engineering Technology Research Center of Organic Toxie Substance Control and Resource Reuse of Jiangsu Province Nanjing 210038 China

Two hypercrosslinked resins with similar physical characters but different surface chemistry were synthesized and used to remove phenol from aqueous solutions. The FTIR spectra, elemental analysis and the Boehm titration were used to characterize the chemical properties of the resins. The adsorption experiments were carried out using the bottle-point technique, and the effects of the surface chemistry on the adsorption were discussed. The adsorption data fit well with the Freundlich model, indicating the heterogeneity of the resins surface. It could be seen from the experimental results that the adsorption capacity increased with the increase in the total surface concentration of oxygen-containing groups. The pH dependence and the effects of ionic strength were also discussed. The kinetic adsorption data fit well with the pseudo-second order model, and the results showed that the surface oxygen-containing groups have little effect on the adsorption rate.

关键词： Hypercrosslinked resin Phenol Surface chemistry Adsorption isotherm Kinetic study.