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山东水利 2024年第2期 17-19页

作者：公衍华邓海瑜高培礼沂水县水利工程保障中心山东沂水276400 沂水县教育与体育局山东沂水276400

为贯彻落实山东省水利厅水利绿化样板创建工作,沂水县通过开展工程绿化、管理管护、宣传示范等措施,打造了“水清、河畅、岸绿、景美”的姚店子河水利绿化样板,取得良好成效,展现了水利绿化风采风貌,为类似工程提供借鉴。

关键词：沂水县姚店子河水利绿化

Excellent tribological properties of epoxy-Ti3C2 with three-dimensional nanosheets composites

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Friction 2021年第4期9卷 734-746页

作者： Fanning MENG Zhenyu ZHANG peili gao Ruiyang KANG Yash BOYJOO Jinhong YU Tingting LIU Key Laboratory for Precision and Non-Traditional Machining Technology of Ministry of Education Dalian University of TechnologyDalian 116024China Key Laboratory of Marine Materials and Related Technologies Zhejiang Key Laboratory of Marine Materials and Protective TechnologiesNingbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

As a widely used engineering polymer,epoxy resin has been successfully employed in high-performance components and ***,the poor thermal and friction properties of traditional epoxy resin greatly limit its application in many extreme *** this work,a new kind of epoxy-Ti3C2 with three-dimensional nanosheets(3DNS)composite which was designed by freeze-drying method showed up excellent thermal and friction *** a result,the coefficient of thermal expansion(CTE)of epoxy-Ti3C23DNS 3.0 composites was 41.9 ppm/K at 40℃,which was lower than that of the traditional epoxy resin(46.7 ppm/K),and the thermal conductivity(TC)was also improved from 0.176 to 0.262 W/(m-K).Meanwhile,epoxy-Ti3C23DNS 1.0 composites showed up the best friction property,with wear rate 76.3%lower than that of epoxy *** work is significant for the research of high-performance composite materials.

关键词： epoxy-Ti3C23DNS composite three-dimensional nanosheets thermal performances friction properties

Non-spherical abrasives with ordered mesoporous structures for chemical mechanical polishing

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Science China Materials 2021年第11期64卷 2747-2763页

作者： peili gao Tingting Liu Zhenyu Zhang Fanning Meng Run-Ping Ye Jian Liu Key Laboratory for Precision and Non-Traditional Machining Technology of Ministry of Education Dalian University of TechnologyDalian 116024China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China DICP-Surrey Joint Centre for Future Materials Department of Chemical and Process Engineeringand Advanced Technology InstituteUniversity of SurreySurrey GU27XHUnited Kingdom

The chemical mechanical polishing(CMP)technology has been widely used for surface modification of critical materials and components with high quality and *** a typical CMP process,the mechanical properties of abrasives play a vital role in obtaining the ultra-precision and damage-free surface of wafers for improvement of their *** this work,a series of fine structured rod-shaped silica(RmSiO2)-based abrasives with controllable sizes and diverse ordered mesoporous structures were synthesized via a soft template approach,and successfully applied in the sustainable polishing slurry for improving the surface quality of cadmium zinc telluride(CZT)*** with commercial silica gel,solid and mesoporous silica spheres,the RmSiO2 abrasives present superior elastic deformation capacity and surface precision machinability on account of their mesoporous structures and rod ***,ultra-precision surface roughness and relatively effective material removal speed were achieved by the CMP process using the RmSiO2 abrasives with a length/diameter(L/d)ratio of *** addition,a potential CMP mechanism of the developed polishing slurry to CZT wafer was elucidated by analyzing X-ray photoelectron spectra and other *** proposed interfacial chemical and mechanical effects will provide a new strategy for improving abrasives’machinability and precision manufacture of hard-to-machine materials.

关键词： non-spherical abrasives mesoporous structure chemical mechanical polishing interfacial mechanochemistry

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面光源矩形匀光照明反射器数学建模分析

应用光学 2016年第1期37卷 136-141页

作者：高培丽李潇黄逸峰钱维莹刘诚高淑梅江南大学理学院江苏省轻工光电工程技术研究中心江苏无锡214000

通常反射器照明器件结构对面光源出射光线难以有效控制,用透镜又存在不可避免的色散问题。采用面光源置于反射器杯口,出光面背对目标面的结构,提出一种分点、分区控制光线的自由曲面反射器的设计方法。利用有限元法划分面光源,将微面光... 详细信息

通常反射器照明器件结构对面光源出射光线难以有效控制,用透镜又存在不可避免的色散问题。采用面光源置于反射器杯口,出光面背对目标面的结构,提出一种分点、分区控制光线的自由曲面反射器的设计方法。利用有限元法划分面光源,将微面光源视为点光源,根据矩形匀光照明配光条件,建立面光源与目标面的能量对应关系。根据微分几何理论和Snell定律,建立反射器的数学模型,只要给定参数,无需进行反馈优化,即可用Matlab软件给出自由曲面反射器的数值解。以台灯照明为例,用光学设计软件对其性能进行了模拟应用分析,结果表明,在有效照明区域内均匀度可达到80%以上,光能利用率达到90%。

关键词：光学设计自由曲面反射器有限元法矩形均匀照明 LED面光源

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大面型LED紧凑型匀透镜优化设计

激光与光电子学进展 2015年第4期52卷 148-154页

作者：徐超高淑梅钱维莹刘诚高培丽江南大学理学院江苏无锡214000

通常的商用和民用LED照明都期望照明器件小型化,同时具有高光通量和照明均匀度。近年市场出现的板上芯片(COB)-LED可以具有较高的光通量,但在有限的区域实现特定的照度分布就需要通过二次光学设计来实现。针对大面型COB-LED加紧凑型自... 详细信息

通常的商用和民用LED照明都期望照明器件小型化,同时具有高光通量和照明均匀度。近年市场出现的板上芯片(COB)-LED可以具有较高的光通量,但在有限的区域实现特定的照度分布就需要通过二次光学设计来实现。针对大面型COB-LED加紧凑型自由曲面透镜的小型照明器件,提出了一种在圆形照明区域内实现均匀照明的快速优化设计方法。优化设计时,以等弧长方法有效减少优化点的选取,提高优化效率。结合三次样条插值理论和自定义优化函数,在Trace Pro软件二次开发环境中实现了目标区域的均匀照明,照明均匀性和光能利用率分别达到90%和95%以上。该方法还适用于COB-LED芯片一次封装匀透镜的设计。

关键词：光学设计板上芯片自由曲面紧凑型透镜优化设计均匀照明

Record-high efficiency perovskite LEDs achieved by accelerating radiative recombination

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Science China Materials 2024年第9期67卷 3039-3040页

作者： Feng gao Department of Physics Chemistry and BiologyLinköping UniversityLinköping58183Sweden

Light-emitting diodes(LEDs)have revolutionized the lighting and displays due to their superior energy *** increasing demand for more efficient and brighter thin-film LEDs in flat-panel displays and solid-state lighting applications has driven extensive research into perovskite materials,which show great promise for high brightness and efficiency.

关键词： lighting radiative high

股骨颈系统与空心拉力螺钉治疗股骨颈骨折近期临床疗效比较

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重庆医科大学学报 2022年第4期47卷 427-432页

作者：高培栗罗刚倪卫东重庆医科大学附属第一医院骨科重庆400016

目的:探讨股骨颈系统(femoral neck system,FNS)治疗股骨颈骨折的近期临床疗效。方法:采用回顾性病例对照研究分析2019年1月至2020年12月收治的45例股骨颈骨折患者临床资料,其中男性23例,女性22例,年龄28~68岁,平均年龄(52.3±11.2)岁... 详细信息

目的:探讨股骨颈系统(femoral neck system,FNS)治疗股骨颈骨折的近期临床疗效。方法:采用回顾性病例对照研究分析2019年1月至2020年12月收治的45例股骨颈骨折患者临床资料,其中男性23例,女性22例,年龄28~68岁,平均年龄(52.3±11.2)岁。根据Pauwels分型,Ⅰ型6例,Ⅱ型23例,Ⅲ型16例。24例采用空心拉力螺钉固定设为A组;21例采用FNS固定设为B组。比较2组患者手术时间、术中出血量、复位质量、完全负重时间、骨折愈合时间、股骨头坏死、骨折不愈合、股骨颈短缩、内固定物退钉等情况以及末次随访患髋功能评分。结果:患者均获随访6~29个月,A组手术时间为(65.2±21.5)min,B组为(58.4±14.5)min(P>0.05)。A组术中出血量为(35.6±51.2)m L,B组出血量为(72.1±62.1)mL(P0.05)。A组完全负重时间为(2.9±1.3)个月,B组为(3.1±1.5)个月(P>0.05)。A组骨折愈合时间为(4.4±1.4)个月,B组为(4.5±1.5)个月(P>0.05)。A组股骨头坏死2例,骨折不愈合4例,股骨颈短缩7例;B组股骨头坏死1例,骨折不愈合3例,股骨颈短缩6例(P>0.05)。A组退钉4例(17.67%),B组无退钉情况(P=0.05)。A组患者末次随访Harris评分(91.2±6.9)分;B组(92.0±7.5)分(P>0.05)。在PauwelsⅢ型患者中,A组患者末次随访Harris评分(89.7±4.8)分;B组(93.4±6.3)分(P>0.05),A组骨不连及股骨头坏死的总体发生率为33.33%,B组无骨不连及坏死发生(P>0.05)。结论:运用FNS治疗股骨颈骨折可以取得与空心拉力螺钉治疗相当的临床疗效,FNS可成为治疗股骨颈骨折的新选择。

关键词：股骨颈骨折空心拉力螺钉股骨颈系统内固定

Stress tensor determination by modified hydraulic tests on pre-existing fractures:Method and stress constraints

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1637-1648页

作者： Guiyun gao Chenghu Wang Ke gao National Institute of Natural Hazards Ministry of Emergency Management of ChinaBeijing100085China Beijing Engineering Research Center of Earthquake Observation Beijing100085China Key Laboratory of Compound and Chained Natural Hazards Dynamics Ministry of Emergency Management of ChinaBeijing100085China Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen518055China

The hydraulic testing of pre-existing fractures(HTPF)is one of the most promising in situ stress measurement methods,particularly for three-dimensional stress tensor ***,the stress tensor determination based on the HTPF method requires at least six tests or a minimum of 14-15 tests(under different conditions)for reliable *** this study,we modified the HTPF method by considering the shear stress on each pre-existing fracture,which increased the number of equations for the stress tensor determination and decreased the number of tests *** shear stresses were attributed to different fractures by random sampling;therefore,the stress tensors were obtained by searching for the optimal solution using the least squares criterion based on the Monte Carlo ***,we constrained the stress tensor based on the tensile strength criterion,compressive strength criterion,and vertical stress *** inverted stress tensors were presented and analyzed based on the tensorial nature of the stress using the Euclidean mean stress *** stress-measurement campaigns in Weifang(Shandong Province,China)and Mercantour road tunnel(France)were implemented to highlight the validity and efficiency of the modified HTPF(M-HTPF)*** results showed that the M-HTPF method can be applied for stress tensor inversion using only three to four tests on pre-existing fractures,neglecting the stress *** inversion results were confined to relatively small distribution dispersions and were significantly reliable and stable due to the shear stresses on the fractures and the stress constraints *** M-HTPF method is highly feasible and efficient for complete stress tensor determination in a single borehole.

关键词： Stress tensor Hydraulic tests on pre-existing fractures Mean stress Stress constraint Hydraulic fracturing

Thermal and mechanical behavior of casting copper alloy wheel during wheel and belt continuous casting process

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China Foundry 2024年第1期21卷 82-90页

作者： Kun gao Yan Peng School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina

To investigate the thermal and mechanical behavior of casting wheel,a two-dimensional thermoelastic-plastic finite element model was used to predict the temperature,stress and distortion distribution of the casting wheel during the wheel and belt continuous casting *** effects of grinding thickness and casting speed on the thermal and mechanical behaviors of the center of the hot face of the casting wheel were discussed in *** each rotation,the casting wheel passes through four different spray *** results show that the temperature distribution of the casting wheel in different spray zones is similar,the temperature of the hot face is the highest and the temperature reaches the peak in the spray zoneⅢ.The stress and distortion depend on the temperature distribution,and the maximum stress and distortion of the hot face are 358.2 MPa and 1.82 mm,*** temperature at the center of the hot face decreases with increasing grinding thickness and increases with increasing casting speed.

关键词： casting wheel finite element model grinding thickness casting speed hot face spray zones

Numerical simulation of fluid flow and free surface fluctuations during wheel and belt casting process

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Journal of Iron and Steel Research International 2024年第5期31卷 1117-1126页

作者： Kun gao Yan Peng National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao066004HebeiChina

The unstable fluid flow and severe free surface fluctuations in the wheel and belt caster can affect the quality of the cast *** lower level height tends to entrap inclusions in the molten *** the other hand,the higher level height makes the production process more dangerous due to the overflow of high temperature fluid from the mold.A computational model of the molten metal pouring process was *** transient fluid flow and free surface fluctuations behavior were calculated using the three-dimensional large eddy simulation model and the volume of fluid *** results show that the flow velocity of the main jet gradually decreases under the influence of the low kinetic energy fluid in the *** is an obvious oscillation in the tail of the jet,while the flow field is asymmetric in *** jet is closer to the inside radius side due to the Coanda effect,and there is a recirculation zone on the inside radius and the outside radius respectively,according to the 10 s time-averaged *** with the industrial observation and simulation results,the shape of the free surface is a wave that varies with *** addition,the free surface height is lowest and the flow velocity is highest in the region near the jet.

关键词： Fluid flow Free surface Wheel and belt caster Large eddy simulation Volume of fluid method