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Research progress in CALPHAD assisted metal additive manufacturing

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China Foundry 2024年第4期21卷 295-310页

作者： Ya-qing Hou Xiao-qun Li Wei-dong cai qing chen Wei-ce Gao Du-peng He Xue-hui chen Hang Su China Iron&Steel Research Institute Group Beijing 100081China Thermo-Calc Software AB SolnaSE-169Sweden KTH Royal Institute of Technology StockholmSE-100Sweden Central Iron and Steel Research Institute Beijing 100081China

Metal additive manufacturing(MAM)technology has experienced rapid development in recent *** both equipment and materials progress towards increased maturity and commercialization,material metallurgy technology based on high energy sources has become a key factor influencing the future development of *** calculation of phase diagrams(CALPHAD)is an essential method and tool for constructing multi-component phase diagrams by employing experimental phase diagrams and Gibbs free energy models of simple *** combining with the element mobility data and non-equilibrium phase transition model,it has been widely used in the analysis of traditional metal *** development of CALPHAD application technology for MAM is focused on the compositional design of printable materials,the reduction of metallurgical imperfections,and the control of microstructural *** endeavor carries considerable theoretical and practical *** paper summarizes the important achievements of CALPHAD in additive manufacturing(AM)technology in recent years,including material design,process parameter optimization,microstructure evolution simulation,and properties ***,the limitations of applying CALPHAD technology to MAM technology are discussed,along with prospective research directions.

关键词： metal additive manufacturing CALPHAD integrated computational material engineering powder bed fusion material design microstructure simulation

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BIM模型数据轻量化方法研究

建筑技术 2019年第4期50卷 455-457页

作者：陈庆财冯蕾梁建斌于跃牛彦涛北京未来科学城科技发展有限公司北京102200 中新城镇化(北京)科技有限责任公司北京100037

设计一种轻量化的建筑信息模型(BIM)的文件结构(LBSF),该文件结构能与地理信息系统(GIS)有效集成,流畅展示复杂的BIM几何对象。近年来,基于GIS的城市设施管理研究增多,需使用GIS在园区甚至城市层面有效地可视化展示BIM几何对象,为此设... 详细信息

设计一种轻量化的建筑信息模型(BIM)的文件结构(LBSF),该文件结构能与地理信息系统(GIS)有效集成,流畅展示复杂的BIM几何对象。近年来,基于GIS的城市设施管理研究增多,需使用GIS在园区甚至城市层面有效地可视化展示BIM几何对象,为此设计一种轻量级BIM数据结构并实现了原型系统。LBSF文件开发后,对数据量和加载性能进行比较,取得了较好效果。

关键词：建筑信息模型(BIM) 多细节层次(LOD) 轻量化文件结构(LBSF)

Systematic diesel molecular performance evaluation based on quantitative structure-property relationship model

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Petroleum Science 2022年第2期19卷 809-818页

作者： Guang-qing cai Lin-Zhou Zhang State Key Laboratory of Heavy Oil Processing Petroleum Molecular Engineering Center(PMEC)China University of PetroleumBeijing 102249China

The production and separation of optimal molecules in diesel fuels require a systematic property evaluation for the containing *** paper evaluates the diesel molecules based on four key quality indicators:low-temperature fluidity,cleanliness,ignition,and power *** established the corresponding quantitative structure-property relationship models for corresponding properties,which are freezing point,yield sooting index,cetane number,and combustion *** models were applied for the screening of the high-performance molecules that is suitable for *** molecular performance distribution of the conventional diesel and biodiesel were also ***,we analyzed the effect of different transformation paths on molecular properties,giving guidance on the conversion process design.

关键词： Diesel Optimal molecules QSPR Molecular screening

Study on Dragline-Bulldozer Operation with Variations in Coal Seam Thickness

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Journal of China University of Mining and Technology 2007年第4期17卷 464-466页

作者： ZHOU Wei cai qing-xiang chen Shu-zhao School of Mining and Safety Engineering China University of Mining ＆Technology Xuzhou Jiangsu 221008 China

The dragline is one of the most promising surface mining machines in China. This paper studies the interac-tion between the working bench advancing speed and the stripping volume with variation in coal seam thickness. Ad-justing the bulldozing volume (depth) and/or changing the dragline bench height are proposed as means to ensure a smooth and economical mining operation. When the coal seam is getting thicker it is recommended to reduce the bull-dozing volume (depth) for a higher dragline efficiency. When the coal seam is getting thinner it is recommended to in-crease the bulldozing volume (depth) to ensure the dragline can work at the proper bench height.

关键词： open pit coal thickness variation dragline adaptability bulldozer

Bifurcation and catastrophe of seepage flow system in broken rock

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Mining Science and Technology 2009年第1期19卷 1-7页

作者： MIAO Xie-xing LI Shun-cai chen Zhan-qing School of Sciences China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China School of Mechanical and Electrical Engineering Xuzhou Normal University Xuzhou Jiangsu 221116 China

The study of dynamical behavior of water or gas flows in broken rock is a basic research topic among a series of key projects about stability control of the surrounding rocks in mines and the prevention of some disasters such as water inrush or gas outburst and the protection of the groundwater resource. It is of great theoretical and engineering importance in respect of promo- tion of security in mine production and sustainable development of the coal industry. According to the non-Darcy property of seepage flow in broken rock dynamic equations of non-Darcy and non-steady flows in broken rock are established. By dimensionless transformation, the solution diagram of steady-states satisfying the given boundary conditions is obtained. By numerical analysis of low relaxation iteration, the dynamic responses corresponding to the different flow parameters have been obtained. The stability analysis of the steady-states indicate that a saddle-node bifurcaton exists in the seepage flow system of broken rock. Consequently, using catastrophe theory, the fold catastrophe model of seepage flow instability has been obtained. As a result, the bifurcation curves of the seepage flow systems with different control parameters are presented and the standard potential function is also given with respect to the generalized state variable for the fold catastrophe of a dynamic system of seepage flow in broken rock.

关键词： broken rock non-Darcy flow stability saddle-node bifurcation fold catastrophe

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主路式水肥一体机施肥系统的设计与试验

农机化研究 2025年第2期47卷 68-74页

作者：李擎李家春熊贤沙蔡家斌贵州大学机械工程学院贵阳550025

针对现阶段水肥一体化设备存在施肥不均、自动化程度不高及滞后性严重的问题,根据现代化农业节水省肥和减少环境污染的灌溉要求,设计了一款可实现自动混肥、施肥、节水灌溉的主路式水肥一体化施肥机。根据液肥的EC和pH值调节过程的特点... 详细信息

针对现阶段水肥一体化设备存在施肥不均、自动化程度不高及滞后性严重的问题,根据现代化农业节水省肥和减少环境污染的灌溉要求,设计了一款可实现自动混肥、施肥、节水灌溉的主路式水肥一体化施肥机。根据液肥的EC和pH值调节过程的特点,开发了以SIEMENS S7-1200为核心的液肥控制系统硬件,并结合MatLab设计了以模糊PID为控制器的液肥EC和pH值控制系统。为验证施肥机在实际应用中的精确性和鲁棒性,设计了施肥系统动态调节性能试验,结果表明:在施肥阶段,模糊PID控制系统具有较短的稳态时间和较小的超调量,相比于PID控制系统,对EC和pH值进行调节的稳态时间分别减少了37.7%和52.1%,稳态超调量分别降低了1.2%和2.2%,可实现对混肥溶液进行迅速有效的调节,满足现代农业实际生产需要。

关键词：水肥一体化施肥机模糊PID 过程控制

Moisture transport and sources of an extreme rainfall event of June 2021 in southern Xinjiang, China

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Advances in Climate Change Research 2022年第6期13卷 843-850页

作者： Yang-Ruixue chen Bo LIU Xin cai Tian-Jun ZHOU qing HE Plateau Atmosphere and Environment Key Laboratory of Sichuan Province School of Atmospheric SciencesChengdu University of Information TechnologyChengdu 610225China Department of Atmospheric Science School of Environmental StudiesChina University of GeosciencesWuhan 430074China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100029China Institute of Desert Meteorology China Meteorology AdministrationUrumqi 830013China Center of Central Asia Atmospheric Science Research China Meteorology AdministrationUrumqi 830013China

A highly extreme rainfall event occurred during June 15-17,2021(21·6 event)over southern Xinjiang(SXJ)of China,with daily rainfall overwhelming the climatological annual total at three national stations along the north of Kunlun *** this event,the SXJ is situated upstream of the 500 hPa trough line and close to the 200 hPa upper jet stream entrance,favouring the upper(lower)level divergence(convergence)with intensified ascending motions and prominent moisture *** examined the moisture paths and sources for this significant rainfall event using the Hybrid Single-Particle Lagrangian Integrated Trajectory(HYSPLT)*** findings indicate that the majority of the moisture sources are located in areas west of the SXJ,extending from central Asia to the North Atlantic,whereas only a small number of trajectories originate from areas south or east of the *** relevant moisture sources for the rainfall event have been *** 80.0%of the total moisture is contributed by central Asia,which ranks top in terms of moisture contribution(∼33.2%),north Eurasia(∼25.7%),and water areas(∼17.7%),including the Mediterranean,Black and Caspian Sea region,while fractional moisture contributions among the other four regions are all below 8.0%.When compared to other parts of China(such as South China and East China),where southerly and/or easterly trajectories are the predominant moisture channels,the distribution patterns of moisture trajectories during this event are noticeably different.

关键词： Extreme precipitation Lagrangian model Southern Xinjiang Moisture sources Moisture pathways

不同内固定系统治疗股骨转子间骨折的力学稳定性

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中国组织工程研究 2025年第9期29卷 1783-1788页

作者：陈曦汤涛陈铜兵李青张文常州市第一人民医院江苏省常州市213003 苏州大学附属第三医院江苏省常州市213003 苏州大学苏州医学院骨科研究所江苏省苏州市215006

背景:股骨转子间骨折的骨折类型和固定方式多样,各固定系统间的力学稳定性相差较大。使用有限元分析方法对各固定系统开展生物力学研究具有科学的临床意义。目的:通过有限元方法对比分析多种内固定应用于股骨A031-A2.1型转子间骨折的力... 详细信息

背景:股骨转子间骨折的骨折类型和固定方式多样,各固定系统间的力学稳定性相差较大。使用有限元分析方法对各固定系统开展生物力学研究具有科学的临床意义。目的:通过有限元方法对比分析多种内固定应用于股骨A031-A2.1型转子间骨折的力学稳定性。方法:在已验证有效性的股骨有限元模型基础上,对模型进行必要的切割,造模成股骨A031-A2.1型转子间骨折,模拟临床手术方法置入不同的内固定系统,分别建立股骨近端防旋髓内钉、动力髋螺钉、经皮加压钢板和股骨近端锁定钢板固定模型。约束4组模型股骨远端下所有节点,在股骨头上施加700,1400和2100N的压缩载荷,通过计算分析,观察各组模型的等效应力分布和压缩刚度,比较各组模型之间的力学稳定性。结果与结论:①通过计算分析,对比各组模型的变形量计算压缩刚度后,在各级载荷作用下,各组模型上压缩刚度呈现的趋势:生理组>股骨近端防旋髓内钉组>股骨近端锁定钢板组>经皮加压钢板组>动力髋螺钉组;完整的生理组模型的压缩刚度明显高于所有的手术组模型;②观察应力指标,因存在应力遮挡效应,致使各固定组的应力峰值均高于生理组,最大峰值均集中分布于各内固定上;其中股骨近端防旋髓内钉固定组应力峰值最小,动力髋螺钉固定组应力最高,应力分布趋势呈现:生理组<股骨近端防旋髓内钉固定组<经皮加压钢板固定组<股骨近端锁定钢板固定组<动力髋螺钉固定组;③分布于骨质模型的应力,因内固定置入位置不同呈现不同的分布结果;④提示对于股骨转子间骨折,各种内固定均能起到有效的固定,结合有限元分析结果得出股骨近端防旋髓内钉组是较好的一种内固定选择,呈现变形量小、应力峰值低,应力分布均匀的特性;经皮加压钢板组和股骨近端锁定钢板组的力学效果优良,固定效果接近股骨近端防旋髓内钉固定;动力髋螺钉固定效果欠佳,同比于其他内固定,其力学稳定性较差。

关键词：股骨转子间骨折内固定系统力学稳定性有限元分析等效应力压缩刚度

Suppressing Effects of Ag Wetting Layer on Surface Conduction of Er Silicide/Si(001) Nanocontacts

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Chinese Physics Letters 2018年第8期35卷 74-78页

作者： qing Han Qun cai State Key Laboratory of Surface Physics and Department of Physics Fudan University Shanghai 200433 Collaborative Innovation Center of Advanced Microstructures Nanjing 210093

Current-voltage electrical characteristics of Er silicide/Si（001） nanocontacts are measured in situ in a scanning tunneling microscopy system. Introduced as a new technique to suppress surface leakage conduction on Si（001）,a silver wetting layer is evaporated onto the substrate surface kept at room temperature with Er Si2 nanoislands already existing. The effects of the silver layer on the current-voltage characteristics of nanocontacts are *** experimental results reveal that the silver layer at coverage of 0.4–0.7 monolayer can suppress effectively the current contribution from the surface conduction path. After the surface leakage path of nanocontacts is obstructed, the ideality factor and the Schottky barrier height are determined using the thermionic emission theory, about 2 and 0.5 eV, respectively. The approach adopted here could shed light on the intrinsic transport properties of metal-semiconductor nanocontacts.

关键词： Ag Suppressing Effects of Ag Wetting Layer on Surface Conduction of Er Silicide/Si Nanocontacts