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A resonant high-pressure microsensor based on a composite pressure-sensitive mechanism of diaphragm bending and volume compression

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Microsystems & Nanoengineering 2024年第2期10卷 57-66页

作者： Pan Qian Zongze Yu Jie Yu Yulan Lu Bo Xie jian Chen Deyong Chen Junbo Wang The State Key Laboratory of Transducer Technology Aerospace Information Research InstituteChinese Academy of SciencesBeijing100190China The School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijing100049China

In this paper,a composite pressure-sensitive mechanism combining diaphragm bending and volume compression was developed for resonant pressure microsensors to achieve high-pressure measurements with excellent *** composite mechanism was explained,and the sensor structure was designed based on theoretical analysis and finite element *** all-silicon resonant high-pressure microsensor with multiple miniaturized cavities and dual resonators was developed,where dual resonators positioned in two resonant cavities with suitably different widths are used to perform opposite characteristics in pressure and the same characteristics at different temperatures,which can improve pressure sensitivities and realize temperature self-compensation by differential frequency *** microsensor was fabricated by microfabrication,and the experimental results showed that the sensor had an accuracy of±0.015%full scale(FS)in a pressure range of 0.1~100 MPa and a temperature range of−10~50℃.The pressure sensitivity of the differential frequency was 261.10 Hz/MPa(~2523 ppm/MPa)at a temperature of 20℃,and the temperature sensitivities of the dual resonators were−1.54 Hz/℃(~−14.5 ppm/℃)and−1.57 Hz/℃(~−15.6 ppm/℃)at a pressure of 2 *** differential output had an outstanding stability within±0.02 Hz under constant temperature and ***,this research provides a convenient solution for high-pressure measurements because of its advantages,namely,large range,excellent accuracy and stability.

关键词： stability resonant bending

航空发动机轴承腔油气两相流流动数值研究及验证

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航空动力学报 2014年第11期29卷 2751-2757页

作者：吕亚国张美华刘振侠胡剑平西北工业大学动力与能源学院西安710072

为检验传统的单向耦合模型是否适用于轴承腔油气两相流流场计算,建立了双向耦合模型.对比分析不同转速喷油后,两种模型腔内空气速度和湍动能的分布.并将双向耦合模型计算的数据与文献中实验数据对比.结果表明：喷油后空气速度分布总体... 详细信息

为检验传统的单向耦合模型是否适用于轴承腔油气两相流流场计算,建立了双向耦合模型.对比分析不同转速喷油后,两种模型腔内空气速度和湍动能的分布.并将双向耦合模型计算的数据与文献中实验数据对比.结果表明：喷油后空气速度分布总体变化规律与单相空气流动相似,但各点处空气速度均明显下降,平均空气速度在转速为8 000r/min时变化最快;油滴的运动与蒸发对空气速度和湍动能影响较大,尤其是腔室主流区域空气速度由于油滴的耦合作用将会下降10%~15%,所以油滴对空气场的作用不能忽略.

关键词：航空发动机轴承腔双向耦合空气速度湍动能

An Underwater Biomimetic Robot that can Swim,Bipedal Walk and Grasp

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Journal of Bionic Engineering 2024年第3期21卷 1223-1237页

作者： Qiuxuan Wu Liwei Pan FuLin Du ZhaoSheng Wu XiaoNi Chi FaRong Gao jian Wang Anton A.Zhilenkov School of Automation Hangzhou Dianzi UniversityHangzhou310018China International Joint Research Laboratory for Autonomous Robotic Systems Hangzhou310018China GEELY Automotive Institute Hangzhou Vocational and Technical CollegeHangzhou310018China Institute of Hydrodynamics and Control Processes Sankt-Petersburg Saint Petersburg State Marine Technical UniversitySankt-PetersburgRussia

In developing and exploring extreme and harsh underwater environments,underwater robots can effectively replace humans to complete *** meet the requirements of underwater flexible motion and comprehensive subsea operation,a novel octopus-inspired robot with eight soft limbs was designed and *** robot possesses the capabilities of underwater bipedal walking,multi-arm swimming,and grasping *** closely interact with the underwater seabed environment and minimize disturbance,the robot employs a cable-driven flexible arm for its walking in underwater floor through a bipedal walking *** multi-arm swimming offers a means of three-dimensional spatial movement,allowing the robot to swiftly explore and navigate over large areas,thereby enhancing its ***,the robot’s walking arm enables it to grasp and transport objects underwater,thereby enhancing its practicality in underwater environments.A simplified motion models and gait generation strategies were proposed for two modes of robot locomotion:swimming and walking,inspired by the movement characteristics of octopus-inspired multi-arm swimming and bipedal *** experimental verification,the robot’s average speed of underwater bipedal walking reaches 7.26 cm/s,while the horizontal movement speed for multi-arm swimming is 8.6 cm/s.

关键词： Underwater soft robots Underwater bipedal walking Multi-arm swimming Cable drive

Solidification crack characteristics and sensitivity of peritectic steel

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Journal of Iron and Steel Research International 2024年第7期31卷 1668-1679页

作者： Ya-qiang Li jian-hua Liu Zi-ming Wang Ying-ying Li Yang He Xiao-wei Li Department of Automotive Engineering Hebei Vocational University of Technology and EngineeringXingtai 054000HebeiChina Hebei Special Vehicle Modification Technology Innovation Center Hebei Vocational University of Technology and EngineeringXingtai 054000HebeiChina Institute of Engineering Technology University of Science and Technology BeijingBeijing 100083China School of Petroleum and Natural Gas Engineering Changzhou UniversityChangzhou 213164JiangsuChina

The characteristics and sensitivity of solidification cracks in peritectic steels were investigated using directional solidifi-cation *** cracks were observed in both hypoperitectic steels(12CrlMoV,15CrMo)and hyper-peritectic steel(20CrMo)during solidification at growth velocities of 15,50,and 80 pm/*** the dendritic boundaries,sulphide precipitates were found,promoting crack *** on the statistical analysis of interdendritic cracks in peritectic steels,the area ratio(RA)of interdendritic cracks in a directional solidification structure was proposed to evaluate the crack sensitivity of peritectic ***,the crack sensitivities of peritectic steels(12CrlMoV,15CrMo,and 20CrMo)were tested,evaluated,and compared with the surface crack rates of three types of steels produced from a steel *** results demonstrated that RA was in good agreement with that of the steel plant,and the crack sensitivity of 12CrlMoV steel was the strongest,followed by that of 15CrMo and 20CrMo ***,RA can be used to evaluate the crack sensitivity of peritectic steel.

关键词： Peritectic steel-Directional solidification Growth velocity Dendritic structure Solidification crack Crack sensitivity

基于Simufact的外拘束对焊接热循环参数的影响

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金华职业技术学院学报 2014年第3期14卷 59-63页

作者：张建黄明胡忠建毕节市工业学校贵州毕节551700

焊条电弧焊焊接时由于热源在移动,母材金属各点经历着热循环的历程,这种历程不仅会使焊接母材的组织和性能产生不均匀变化,同时还会使焊接区域产生扭转、残余应力和变形。为了提高焊接的质量,简化焊条电弧焊焊接的实验过程,运用Simufact... 详细信息

焊条电弧焊焊接时由于热源在移动,母材金属各点经历着热循环的历程,这种历程不仅会使焊接母材的组织和性能产生不均匀变化,同时还会使焊接区域产生扭转、残余应力和变形。为了提高焊接的质量,简化焊条电弧焊焊接的实验过程,运用Simufact-Welding软件对Q345钢进行T形焊接仿真,对比分析焊件不完全约束和完全约束两种方法下在焊条电弧焊焊接过程中熔合线处的加热速度、加热最高温度、高温持续时间和t8/5时间。结果表明:该仿真过程中,其它参数相同的情况下,不同的焊件装夹方法得到不同结果的热循环参数,不完全约束下的加热速度比完全约束方法下的加热速度快且平稳,加热最高温度高,高温持续时间平稳,不预热t8/5时间长。

关键词： Simufact 焊条电弧焊热循环外拘束

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沙棘籽中原花色素的提取工艺研究

食品科学 2005年第3期26卷 165-169页

作者：徐晓云潘思轶胡建中华中农业大学食品科学技术学院湖北武汉430070

本文以脱脂沙棘籽为原料,乙醇为提取液,通过提取温度、提取时间、脱脂时间、料液比、酒精浓度、pH值6个单因素实验,在中心组合实验基础上,采用响应面分析法,确定沙棘籽中原花色素的最优提取条件。研究结果表明,在提取温度21℃、pH5.1、... 详细信息

本文以脱脂沙棘籽为原料,乙醇为提取液,通过提取温度、提取时间、脱脂时间、料液比、酒精浓度、pH值6个单因素实验,在中心组合实验基础上,采用响应面分析法,确定沙棘籽中原花色素的最优提取条件。研究结果表明,在提取温度21℃、pH5.1、酒精浓度65%时,沙棘籽中原花色素的提取率达5.84%(以脱脂沙棘干重计),粗品纯度达39.18%。

关键词：沙棘原花色素提取响应面分析

A reverse particle grading strategy for design and fabrication of porous SiC ceramic supports with improved strength

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Journal of Advanced Ceramics 2024年第7期13卷 1011-1022页

作者： Zheng Liang Han Zhang Yichuan Li Wenkang Zhang jian Zhou Qilin Gu Zhaoxiang Zhong Weihong Xing State Key Laboratory of Materials-Oriented Chemical Engineering National Engineering Research Center for Special Separation MembraneNanjing Tech UniversityNanjing 211816China Nanjing Membrane Application Institute Co. Ltd.Nanjing 210009China

Porous ceramics usually require high mechanical strength and maximized porosity simultaneously,while for conventional particle grading strategies,it is highly challenging to meet both *** this end,a reverse particle grading strategy was developed based on the linear packing model by unusually introducing coarse particles(d_(50)=16μm)into a fine particle(d50=5μm)*** the extrusion and sintering process,tubular porous SiC ceramic supports with improved mechanical strength were successfully *** effects of coarse particles on the rheological properties of the ceramic paste and the macroscopic properties and microstructure of the SiC supports were systematically *** an increase in the content of coarse SiC particles to 30 wt%,the pressure generated during extrusion decreased from 5.5±0.2 to 1.3±0.1 ***,the bending strength of the tubular supports increased from 36.6±5.6 to 49.1±4.5 MPa when 20 wt%coarse powder was *** notably improved mechanical strength was attributed to the distribution of coarse particles that prolonged the route of crack ***,the optimized tubular supports had an average pore size of 1.2±0.1μm,an open porosity of 45.1%±1.6%,and a water permeability of 7163±150 L/(m^(2)·h·bar)as well as good alkali and acid corrosion ***,the strategy was proven to be feasible for the scale-up fabrication of 19-channel SiC tubular porous ceramic supports.

关键词： porous SiC ceramic tubular ceramic support reverse particle grading reaction bonding chemical stability

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溶剂法制备PPTA纸结构与性能的研究

中国造纸学报 2007年第2期22卷 72-74页

作者：黄一磊刘焕彬王宜胡健华南理工大学制浆造纸工程国家重点实验室广东广州510641

提出了一种溶剂法增强、制备全PPTA(聚对苯二甲酰对苯二胺)纸的思路,采用扫描电子显微镜研究了溶剂法制PPTA纸的纸页结构。研究表明,溶剂法制备的PPTA纸的抗张指数、撕裂指数和耐破指数分别达到72．6N．m/g、43．1mN·m^2/g和5．86kPa·... 详细信息

提出了一种溶剂法增强、制备全PPTA(聚对苯二甲酰对苯二胺)纸的思路,采用扫描电子显微镜研究了溶剂法制PPTA纸的纸页结构。研究表明,溶剂法制备的PPTA纸的抗张指数、撕裂指数和耐破指数分别达到72．6N．m/g、43．1mN·m^2/g和5．86kPa·m^2/g。而且5%热失重温度为518．7℃,具有良好的热性能。

关键词：溶剂法 PPTA纸制备

Highly crystallization-induced emissive luminophores with mechanoluminescent features for two-photon harvesting fluorescence imaging and latent fingerprint identification

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Nano Research 2024年第7期17卷 6475-6482页

作者： jian Lu Juan Gao Rui-Xuan Qian Shuai-hua Wang Fa-Kun Zheng Guo-Cong Guo Fujian Science and Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Fluorescence imaging can be employed in fields of medical treatment,astronomical exploration,and national defense *** fluorescence imaging often takes the single-photon techniques,which is vulnerable to background interference and ***,two-photon fluorescence imaging can achieve much higher-resolution fluorescence imaging for reducing scattering and deeper ***,by assembling the tetraphenylethylene backbones with nontoxic and non-noble K^(+)ions,compound 1([(Hdma)K(H_(2)ettc)]_(n),H_(4)ettc=4',4''',4''''',4'''''''-(ethene-1,1,2,2-tetrayl)tetrakis(([1,1'-biphenyl]-4-carboxylic acid)))with the crystallization-induced emissions exhibited charming fluorescence imaging under two-photon excitation microscopy(TPEM).Besides,luminescent powders based on compound 1 can achieve high-resolution fingerprint recognition,providing secure access control and identification for a novel authentication *** with the commercial fluorescent dyes coumarin-6,the as-synthesized compound 1 showed great solvent stability,indicating its durability against harsh ***,compound 1 shows mechanoluminescent properties for the perturbation of weak supramolecular interactions within ordered arrangements of the H_(2)ettc^(2−)*** novel compound has provided an important insight to the development of twophoton fluorescence imaging and advanced external-stimuli responsive materials.

关键词： crystallization-induced emission fluorescence imaging two-photon absorption fingerprint recognition mechanoluminescence