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硬料螺纹孔铣削加工技术研究

模具工业 2024年第5期50卷 74-77页

作者：胡志涛冯亚坤陈果廖文佳珠海格力精密模具有限公司广东珠海519070

Cr12MoV材料经热处理后硬度达到56~62 HRC,切削性能差,切削难度大,以热处理后Cr12MoV材料的模具零件螺纹孔为例,传统的加工方式一般采用电火花机床进行螺纹孔加工,加工效率低,为提高加工效率采用铣刀铣削加工。经加工测试,得出铣削加工... 详细信息

Cr12MoV材料经热处理后硬度达到56~62 HRC,切削性能差,切削难度大,以热处理后Cr12MoV材料的模具零件螺纹孔为例,传统的加工方式一般采用电火花机床进行螺纹孔加工,加工效率低,为提高加工效率采用铣刀铣削加工。经加工测试,得出铣削加工硬料螺纹孔提升了加工效率,降低了加工成本,在加工过程中更加安全环保。

关键词：硬料螺纹孔加工电火花加工铣削加工刀具规格

2μm波段Ge-on-SOI光电探测器的TPA探测

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光通信研究 2024年第4期 68-72页

作者：胡志涛王柱天欧阳越华黄龙鑫庞拂飞叶楠宋英雄上海大学特种光纤与光接入网重点实验室上海200444

【目的】随着光通信技术的快速发展,工作在传统通信窗口的光通信系统未来可能会面临通信“波段紧缩”的状况。而在2μm波段,空芯光子带隙光纤的损耗可以低至0.2 dB/km,掺铥光纤放大器(型号为CTFA)在2μm波段的增益峰值可达30 dB,这些高... 详细信息

【目的】随着光通信技术的快速发展,工作在传统通信窗口的光通信系统未来可能会面临通信“波段紧缩”的状况。而在2μm波段,空芯光子带隙光纤的损耗可以低至0.2 dB/km,掺铥光纤放大器(型号为CTFA)在2μm波段的增益峰值可达30 dB,这些高性能器件的出现使得2μm波段有缓解通信“波段紧缩”的潜力,同时也对制作难度小且利于大规模生产的2μm波段硅基光电探测器提出了需求。硅基光电探测器的工作波段扩展主要方案有采用具有可调谐带隙的Ⅲ-Ⅴ族材料、引入低带隙宽度材料作为吸收区和利用吸收区材料在2μm波段新的光吸收机制等。而Ge具有非常高的双光子吸收(TPA)系数(1225 GW/cm@2μm),并且Ge-on-绝缘体上硅(SOI)光电探测器结构兼容标准硅光器件制作工艺,具有制作难度较低和成本较低的优势,是2μm光电探测器的一种较优方案。文章的研究目的是验证Ge-on-SOI光电探测器利用TPA这一特殊光吸收机制实现2μm波段光电探测的可行性。【方法】文章基于Ge材料在2μm波段较高的TPA效应产生电流的物理机制实现了2μm波段的光电探测。理论上,对Ge材料通过TPA效应产生的光生电流大小进行了分析与讨论;在实验上,基于片上硅基器件有源测试系统对商用波导型Ge-on-SOI光电探测器的光输入端(光栅耦合器)施加经过掺铥光纤放大器放大后的高功率2μm波段输入光,并调整光纤与光栅的对准以及输入光偏振态以尽可能减少输入光传输到Ge吸收层的损耗,最终通过探针获取探测器的TPA光生电流。【结果】在功率为21.9 dBm的2μm光信号输入下,该商用波导型Ge-on-SOI光电探测器在2μm波段产生了高至651 nA的TPA净光生电流,并近似获得了>10 mA/W的响应度。【结论】文章验证了通过Ge材料TPA效应实现2μm波段光电探测器的科学可行性,为基于TPA的2μm波段Ge-on-SOI光电探测器的设计提供了实验支撑。

关键词： 2μm波段双光子吸收 Ge-on-绝缘体上硅光电探测器

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Study on three-dimensional expansion characteristics of four wall combustion-gas jets in confined liquid space

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Acta Mechanica Sinica 2017年第2期33卷 341-355页

作者： zhitao hu Yonggang Yu School of Energy and Power Engineering Nanjing University of Science and Technology Nanjing 210094 China

To explore further the launch mechanism of the new underwater launching technology proposed in this paper, the expansion characteristics of four wall combustion-gas jets in confined liquid space must be studied firstly. The experimental device is designed, and the high-speed digital photographic system is adopted to obtain the expansion sequence processes of Taylor cavities formed by the four wall jets. Meanwhile, the influence of the injection pressure on the axial expansion property of the four wall jets is discussed. Based on the experiments, a three-dimensional unsteady mathematical model is established to simulate the turbulent flow process of the four wall jets expanding in liquid, and the temporal and spatial distribution laws of phase, pressure, temperature, and velocity and the evolution rules of vortices are illustrated in detail. Results show that, accompanied by the jets expanding downstream, the four wall combustion-gas jets get close to each other and achieve convergence eventually under induction of the interference effect between multiple jets. Meanwhile, the heads of the Taylor cavities separate from the observation chamber wall and offset to the central axis of the observation chamber with time going on. The numerical simulation results of the four wall combustion-gas jets coincide well with the experimental data.

关键词： Wall jet Taylor cavity Kelvin-Helmholtz instability Interference effect

α-LTX and α-LTX^(N4C) induce [Ca^(2+)]i elevation through different mechanisms in pancreatic β cells

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Chinese Science Bulletin 2006年第2期51卷 158-163页

作者： JIU Yaming hu zhitao LIU Jie WU Zhengxing XU Tao Institute of Biophysics and Biochemistry School of Life Science and Technology Huazhong University of Science and Technology Wuhan 430074 China National Laboratory of Biomacromolecules Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China

α-latrotoxin (α-LTX), a neurotoxin from black-widow spider, causes vesicles release in pre- synapse of nerve terminal after binding to specific membrane receptors. α-LTXN4C is an effective tool binding to calcium independent receptor for latrotoxin (CIRL), which is used to elucidate the mechanism of receptor-mediated signal pathway. In our study on the pancreatic β cells, we found that α-LTX inserts into the plasma membrane and forms stable non-selective cation channels. The influx of ex- tracellular Ca2+ through the channels causes massive Ca2+-dependent exocytosis of insulin-containing vesicles, whereas, α-LTXN4C, binding with its receptor CIRL in extracellular divalent cation-dependent way, increases [Ca2+]i by mobilization of the intracellular calcium stores.

关键词：胰腺β细胞 α-LTX α-LTX^N4C 神经毒素蜘蛛毒液钙离子毒性机制

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基于气象因素的机场进离港延误预测

系统工程与电子技术 2023年第6期45卷 1722-1731页

作者：姜雨袁琪胡志韬吴薇薇顾欣南京航空航天大学民航学院江苏南京211106 北京工业大学北京市交通工程重点实验室北京100124

针对机场延误预测过程中难以提取延误传播时空特征、预测结果受天气扰动大的问题,提出了基于气象因素的时空图卷积网络(meteorology-based spatio-temporal graph convolutional networks, MSTGCN)机场延误预测模型。该模型使用图卷积... 详细信息

针对机场延误预测过程中难以提取延误传播时空特征、预测结果受天气扰动大的问题,提出了基于气象因素的时空图卷积网络(meteorology-based spatio-temporal graph convolutional networks, MSTGCN)机场延误预测模型。该模型使用图卷积神经网络(graph convolutional neural network, GCNN)与门控卷积神经网络(gated convolutional neural network, Gated CNN)挖掘机场延误的时空特征,同时加入气象特征提取模块对机场延误时间进行预测。实验结果表明,该模型在中短时预测上的表现均优于其他对比模型;相较于不考虑气象因素的模型,MSTGCN对未来1 h、4 h和12 h预测的平均绝对误差分别降低了7.03%,7.93%,11.54%,对预测结果起到了极大的修正作用。

关键词：机场延误预测图卷积神经网络气象因素机场网络深度学习

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吸附法处理重金属废水污染的研究进展

当代化工研究 2023年第7期 21-23页

作者：胡智涛无棣宜能化工有限公司山东251900

重金属在环境中只能迁移和转化,不能够被降解,因此重金属被排入到环境中以后,会严重破坏生态环境,对动植物和人体健康造成威胁。目前,重金属废水处理已成为急需解决的问题之一,为此需要合理应用现代化技术手段使其能够做到无害化排放,... 详细信息

重金属在环境中只能迁移和转化,不能够被降解,因此重金属被排入到环境中以后,会严重破坏生态环境,对动植物和人体健康造成威胁。目前,重金属废水处理已成为急需解决的问题之一,为此需要合理应用现代化技术手段使其能够做到无害化排放,常见技术方法包括沉淀法、吸附法、电化学法、膜分离法等,其中吸附法因其耗资更少、操作简单,为此被广泛应用于重金属废水污染处理中,以此为后续领域发展提供帮助。通过吸附法处理重金属废水,最为关键的是得到高性能、低成本的吸附剂,本文对吸附法处理重金属废水的原理进行了分析,并且对吸附剂在处理重金属废水的研究进展进行了介绍,探讨吸附法处理重金属废水的机理,包括物理吸附、化学吸附和生物吸附三个部分,随后分析了重金属废水所用吸附剂,包括碳基吸附剂、纳米材料吸附剂、矿物吸附剂、高分子吸附剂以及生物吸附剂,切实提高重金属水污染的处理效果,以期能够为相关人员提供参考和借鉴。

关键词：重金属废水吸附法物理吸附化学吸附生物吸附

R-matrix for the 8-Dimensional Spin Representation of Uq(so7)

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Acta Mathematica Sinica,English Series 2024年第2期40卷 485-497页

作者： Hong Mei hu Nai Hong hu School of Mathematical Sciences Suzhou University of Science and TechnologySuzhou 215009P.R.China School of Mathematical Sciences MOE Key Laboratory of Mathematics and Engineering Applications&Shanghai Key Laboratory of PMMPEast China Normal UniversityShanghai 200241P.R.China

The purpose of the paper is to describe the solution to the quantum Yang-Baxter equation associated with the 8-dimensional spin representation Tsp of Uq(so7).The self-duality of Tsp and the symmetry of the corresponding braiding matrix are ***,the minimal polynomial of the braiding R-matrix of Tsp is presented explicitly in an ingenious method by taking advantage of nice features of the spin representation Tsp.

关键词： Braiding R-matrix spin module minimal polynomial

Mapping out the reaction network of humin formation at the initial stage of fructose dehydration in water

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Green Energy & Environment 2024年第6期9卷 1016-1026页

作者： Xing Fu Yexin hu Ping hu hui Li Shuguang Xu Liangfang Zhu Changwei hu Key Laboratory of Green Chemistry and Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengduSichuan610064China State Key Laboratory of Southwestern Chinese Medicine Resources Innovative Institute of Chinese Medicine and PharmacyChengdu University of Traditional Chinese MedicineChengduSichuan611137China

The formation of humins hampers the large-scale production of 5-hydroxymethylfurfural(HMF)in ***,a detailed reaction network of humin formation at the initial stage of fructose-to-HMF dehydration in water is delineated by combined experimental,spectroscopic,and theoretical *** bimolecular reaction pathways to build up soluble humins are *** is,the intermolecular etherification of β-furanose at room temperature initiates the C12 path,whereas the C-C cleavage of a-furanose at 130-150℃ leads to C11 path,and that of open-chain fructose at 180℃ to C11' *** successive intramolecular dehydrations and condensations of the as-formed bimolecular intermediates lead to three types of soluble *** show that the C12 path could be restrained by using HCl or AlCl_(3) catalyst,and both the C12 and C110 paths could be effectively inhibited by adding THF as a co-solvent or accelerating heating rate via microwave heating.

关键词： Carbohydrates 5-hydroxymethylfurfural Reaction network Soluble humins Tautomer

Investigation of mechanical and electrical characteristics of selfsensing pneumatic torsional actuators

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Science China(Technological Sciences) 2024年第1期67卷 130-142页

作者： XIAO Wei hu DeAn hu GuoLiang XIAO Yihua Key Laboratory of Conveyance and Equipment Ministry of EducationEast China Jiaotong UniversityNanchang 330013China Key Laboratory of Advanced Design and Simulation Techniques for Special Equipment Ministry of EducationHunan UniversityChangsha 410082China

Soft pneumatic actuators are one of the most promising actuation for soft robots,and great achievements have been *** it remains challenging to endow sensing capabilities to pneumatic actuators,especially for the sensing ability originating directly from the actuator ***,a self-sensing pneumatic torsional actuator(SPTA)is designed based on the electromagnetic induction effect and magnetically responsive *** SPTA can generate feedback voltage and current with the deformation,in which the sensing function comes from its inherent *** investigate the mechanical and electrical characteristics,an experimental platform and a finite element model are established,*** find that the torsion angle and output torque increase in nonlinear with the actuating *** maximum torsion angle is 66.35°,which is 84.34%of that for the actuator fabricated by pure *** maximum output torque(24.9 N mm)improves by 23.19%compared with the actuator made by pure *** regards the electrical characteristics,the maximum feedback voltage and current are 2.90μV and 29.50 nA when the SPTA is actuated by a pressure of−40 *** also demonstrate that the relationship between the torsion angle and the magnetic flux change is approximately ***,the number of turns of wires,magnetic powders contents,and magnetic direction on the feedback voltage and current are *** show that the feedback voltage and current can be enhanced by increasing the number of turns and magnetic powders *** envision that the SPTA would be promising for soft robots to realize their accuracy control and intelligentization.

关键词： pneumatic torsional actuators self-sensing feedback voltage finite element modeling soft robots