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Review of small aspheric glass lens molding technologies

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Frontiers of Mechanical Engineering 2017年第1期12卷 66-76页

作者： shaohui yin Hongpeng JIA Guanhua ZHANG Fengjun CHEN Kejun ZHU National Engineering Research Center for High Efficiency Grinding Hunan University Changsha 410082 China School of Mechanical Engineering Xiangtan University Xiangtan411105 China

Aspheric lens can eliminate spherical aberra- tions, coma, astigmatism, field distortions, and other adverse factors. This type of lens can also reduce the loss of light energy and obtain high-quality images and optical characteristics. The demand for aspheric lens has increased in recent years because of its advantageous use in the electronics industry, particularly for compact, portable devices and high-performance products. As an advanced manufacturing technology, the glass lens molding process has been recognized as a low-cost and high-efficiency manufacturing technology for machining small-diameter aspheric lens for industrial production. However, the residual stress and profile deviation of the glass lens are greatly affected by various key technologies for glass lens molding, including glass and mold-die material forming, mold-die machining, and lens molding. These key technical factors, which affect the quality of the glass lens molding process, are systematically discussed and reviewed to solve the existing technical bottlenecks and problems, as well as to predict the potential applicability of glass lens molding in the future.

关键词： aspheric glass lens mold-die manufacturing,lens molding molding process simulation

Fabrication of extreme wettability surface for controllable droplet manipulation over a wide temperature range

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International Journal of Extreme Manufacturing 2022年第4期4卷 246-259页

作者： Chengsong Shu Qitong Su Minghao Li Zhenbin Wang shaohui yin Shuai Huang College of Mechanical and Vehicle Engineering Hunan UniversityChangsha 410082People’s Republic of China National Engineering Research Center for High Efficiency Grinding Hunan UniversityChangsha 410082People’s Republic of China

Droplet controllable manipulation over a wide temperature range has promising applications in microelectronic heat dissipation, inkjet printing, and high temperature microfluidic system. However, the fabrication of a platform for controllable droplet manipulation using the methods commonly used in industry remains a tremendously challenge. The popular method of controlling droplets is highly dependent on external energy input and has relatively poor controllability in terms of droplet motion behaviors and manipulation environment, such as distance, velocity, direction and a wide temperature range. Here, we report a facile and industrially applicable method for preparing Al superhydrophobic (S-phobic) surfaces, which enables controlled droplet bouncing, evaporation, and transport over a wide temperature range. Systematic mechanistic studies are also investigated. Extreme wettability surfaces were prepared on Al substrate by a composite process of electrochemical mask etching and micro-milling. To investigate the evaporation process and thermal coupling characteristics, controlled evaporation and controlled bouncing of droplet in a wide temperature range were conducted. Based on the evaporation regulation and bouncing mechanism of droplets on an extreme wettability surface, by using Laplace pressure gradients and temperature gradients, we realized controlled transport of droplets with confluence, split-flow, and gravity-resistant transport over a wide temperature range, offering a potential platform for a series of applications, such as new drug candidates and water collection.

关键词： extreme wettability surface superhydrophobic controlled evaporation controlled bouncing controlled transport

Halbach阵列与不同励磁方式的磁流变抛光特性及机理研究

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机械工程学报 2023年第15期59卷 341-353页

作者：郭源帆尹韶辉黄帅湖南大学国家高效磨削工程技术中心长沙410082 湖南大学机械与运载工程学院长沙410082

为提高平面磁流变抛光效率,首次提出了一种海尔贝克阵列励磁的平面磁流变抛光方法,并对比研究了不同励磁方式磁流变抛光系统的二维、三维磁场分布、磁性颗粒受力分布特性及其抛光性能,证明了海尔贝克阵列具有优良的励磁性能,可以实现高... 详细信息

为提高平面磁流变抛光效率,首次提出了一种海尔贝克阵列励磁的平面磁流变抛光方法,并对比研究了不同励磁方式磁流变抛光系统的二维、三维磁场分布、磁性颗粒受力分布特性及其抛光性能,证明了海尔贝克阵列具有优良的励磁性能,可以实现高效平面磁流变抛光。对比试验描述了不同装置励磁下,磁流变抛光模形貌特征、抛光压力与痕迹分布、磁流变抛光性能、表面粗糙度与形貌随时间演变的规律,揭示了海尔贝克阵列励磁实现高效平面磁流变抛光的机理。抛光性能试验结果指出,使用N35牌号的钕铁硼永磁材料制造的海尔贝克阵列抛光K9光学玻璃,去除率可达到1.38 mm^(3)/min,是直线气隙磁轭的4.4倍,是N-S极交替阵列的6.9倍。仅需30 min抛光,即可获得表面粗糙度小于Ra 1 nm的超光滑表面。海尔贝克阵列性能优异,配置灵活,大大提高了磁流变抛光的效率,对其他磁流变加工工艺和磁场辅助加工工艺具有借鉴意义。

关键词：磁流变抛光液磁流变抛光海尔贝克阵列磁场 K9光学玻璃

A projected Newton algorithm based on chemically allowed interval for chemical equilibrium computations

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Frontiers of Chemical Science and Engineering 2024年第3期18卷 25-37页

作者： Hongbin Lu shaohui Tao Xiaoyan Sun Li Xia Shuguang Xiang Institute of Process Systems Engineering College of Chemical EngineeringQingdao University of Science and TechnologyQingdao266042China

The chemical equilibrium equations utilized in reactive transport modeling are complex and nonlinear,and are typically solved using the Newton-Raphson *** this algorithm is known for its quadratic convergence near the solution,it is less effective far from the solution,especially for ill-conditioned *** such cases,the algorithm may fail to converge or require excessive *** address these limitations,a projected Newton method is introduced to incorporate the concept of *** method constrains the Newton step by utilizing a chemically allowed interval that generates feasible descending ***,we utilize the positive continuous fraction method as a preconditioning technique,providing reliable initial values for solving the *** numerical results are compared with those derived using the regular Newton-Raphson method,the Newton-Raphson method based on chemically allowed interval updating rules,and the bounded variable least squares method in six different test *** numerical results highlight the robustness and efficacy of the proposed algorithm.

关键词： chemical equilibrium reactive transport modeling numerical methods projected Newton method

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微小非球面光学模具单点斜轴误差补偿磨削

机械工程学报 2013年第17期49卷 59-64页

作者：陈逢军尹韶辉胡天余剑武湖南大学国家高效磨削工程技术研究中心长沙410082

针对微小非球面光学透镜模具的纳米单点斜轴误差补偿磨削进行研究。通过分析比较传统的直交轴磨削法,提出微小非曲面光学模具的单点斜轴磨削方式,有效避免微细砂轮在加工微小非球面时发生干涉情况;采用单点恒定磨削方式提高微小非球面... 详细信息

针对微小非球面光学透镜模具的纳米单点斜轴误差补偿磨削进行研究。通过分析比较传统的直交轴磨削法,提出微小非曲面光学模具的单点斜轴磨削方式,有效避免微细砂轮在加工微小非球面时发生干涉情况;采用单点恒定磨削方式提高微小非球面磨削的稳定性及精度。通过分析磨削区域内微细砂轮与微小非球面的干涉情况,从而合理计算并选用较高强度的微细砂轮。提出微小非球面误差补偿磨削策略,分析砂轮的对心误差(x轴向和y轴向)对形状精度的影响,采用法向残余误差补偿的方法对加工后的形状误差进行超精密补偿磨削。利用超精密磨床对口径为2 mm的超硬热压模具碳化钨材料的微小非球面进行纳米单点斜轴误差补偿磨削试验,经过三次超精密磨削及误差补偿循环,其形状精度PV从1 034 nm改善至146 nm,表面粗糙度达到Ra2.19 nm。

关键词：单点斜轴磨削误差补偿光学模具微小非球面碳化钨

Two-Dimensional Metallophthalocyanine Nanomaterials for Electrocatalytic Energy Conversion

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Energy & Environmental Materials 2024年第4期7卷 364-385页

作者： Xinqi Wang shaohui Sun Jiahao Yao Hao Wan Renzhi Ma Wei Ma School of Chemical Engineering and Zhongyuan Critical Metals Laboratory Zhengzhou University Research Center for Materials Nanoarchitectonics (MANA) National Institute for Materials Science (NIMS)

Crowing energy demand drives the rapid development of clean and reliable energy *** the past years,the exploration of novel materials with considerable efficiency and durability has drawn attention in the area of elec... 详细信息

关键词： conjugated nanostructure electrocatalysis 2D metallophthalocyanines

Chemical Scissors Tailored Nano‑Tellurium with High‑Entropy Morphology for Efficient Foam‑Hydrogel‑Based Solar Photothermal Evaporators

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Nano-Micro Letters 2024年第3期16卷 149-168页

作者： Chenyang Xing Zihao Li Ziao Wang shaohui Zhang Zhongjian Xie Xi Zhu Zhengchun Peng State Key Laboratory of Radio FrequencyHeterogeneous Integration Shenzhen UniversityShenzhen 518060People’s Republic of China Center for Stretchable Electronics and NanoSensors College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060People’s Republic of China School of Science and Engineering The Chinese University of Hong KongShenzhenShenzhen 518172People’s Republic of China Institute of Pediatrics Shenzhen Children’s HospitalShenzhen 518038GuangdongPeople’s Republic of China International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education Institute of Microscale OptoelectronicsShenzhen UniversityShenzhen 518060People’s Republic of China

The development of tellurium(Te)-based semiconductor nanomaterials for efficient light-to-heat conversion may offer an effective means of harvesting sunlight to address global energy ***,the nanosized Te(nano-Te)materials reported to date suffer from a series of drawbacks,including limited light absorption and a lack of surface ***,we report the preparation of nano-Te by electrochemical exfoliation using an electrolyzable room-temperature ionic ***,cations,and their corresponding electrolytic products acting as chemical scissors can precisely intercalate and functionalize bulk *** resulting nano-Te has high morphological entropy,rich surface functional groups,and broad light *** also constructed foam hydrogels based on poly(vinyl alcohol)/nano-Te,which achieved an evaporation rate and energy efficiency of 4.11 kg m^(−2)h^(−1)and 128%,respectively,under 1 sun ***,the evaporation rate was maintained in the range 2.5-3.0 kg m^(−2)h^(−1)outdoors under 0.5-1.0 sun,providing highly efficient evaporation under low light conditions.

关键词： Tellurium High entropy Electrochemical modification Solar absorption Evaporation rate

Experimental study on the influences of cutter geometry and material on scraper wear during shield TBM tunnelling in abrasive sandy ground

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 410-425页

作者： shaohui Tang Xiaoping Zhang Quansheng Liu Qi Zhang Xinfang Li Haojie Wang Key Laboratory of Safety for Geotechnical and Structural Engineering of Hubei Province School of Civil EngineeringWuhan UniversityWuhan430072China State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan430072China

When shield TBM tunnelling in abrasive sandy ground,the rational design of cutter parameters is critical to reduce tool wear and improve tunnelling ***,the influence mechanism of cutter parameters on scraper wear remains unclear due to the lack of a reliable test *** and material optimisation are often based on subjective experience,which is unfavourable for improving scraper geological *** the present study,the newly developed WHU-SAT soil abrasion test was used to evaluate the variation in scraper wear with cutter geometry,material and *** influence mechanism of cutter parameters on scraper wear has been revealed according to the scratch characteristics of the scraper *** geometry and material parameters have been optimised to reduce scraper *** results indicate that the variation in scraper wear with cutter geometry is related to the cutting resistance,frictional resistance and stress *** appropriate increase in the front angle(or back angle)reduces the cutting resistance(or frictional resistance),while an excessive increase in the front angle(or back angle)reduces the edge angle and causes stress *** optimal front angle,back angle and edge angle for quartz sand samples areα=25°,β=10°andγ=55°,*** wear resistance of the modelled scrapers made of different metal materials is related to the chemical elements and *** wear resistances of the modelled scrapers made of 45#,06Cr19Ni10,42CrMo4 and 40CrNiMoA are 0.569,0.661,0.691 and 0.728 times those made of WC-Co,*** the alloy hardness is less than 47 HRC(or greater than 58 HRC),scraper wear decreases slowly with increasing alloy hardness as the scratch depth of the particle asperity on the metal surface stabilizes at a high(or low)***,when the alloy hardness is between 47 HRC and 58 HRC,scraper wear decreases rapidly with increasing alloy hardness as the scratch depth transitions

关键词： Shield TBM Scraper wear Cutter shape Metal material Alloy hardness

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小型高速精密气浮气动主轴的研制

机械科学与技术 2015年第10期34卷 1526-1529页

作者：蒋雷尹韶辉陈逢军湖南大学国家高效磨削工程技术研究中心长沙410082

针对微结构的超精密磨削要求,设计了一种涡轮驱动的小型气浮主轴。采用了涡轮叶片作为动力结构部分,由压力气体驱动,带动主轴高速旋转;同时也采用了空气静压轴承作为支撑;建立了气动涡轮的设计模型,分析了气体静压支承轴承的结构参数,... 详细信息

针对微结构的超精密磨削要求,设计了一种涡轮驱动的小型气浮主轴。采用了涡轮叶片作为动力结构部分,由压力气体驱动,带动主轴高速旋转;同时也采用了空气静压轴承作为支撑;建立了气动涡轮的设计模型,分析了气体静压支承轴承的结构参数,仿真研究了各设计参数对轴承承载力的影响,得出了最佳的设计尺寸和主轴工作参数,对涡轮与转轴组成的整体转子进行了模态分析,计算出了主轴的临界转速,研究了主轴的加工工艺。试验结果表明:该设计合理,达到了设计要求。

关键词：主轴气体轴承涡轮驱动微结构