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齿轮机构精度分析中若干概念问题的研讨

光学技术 1989年第3期15卷 44-46页

作者：盛鸿亮北京理工大学工程光学系

本文讨论了齿轮机构传动误差与空程误差的确切涵义及其相互联系与分析计算单元。在此基础上提出了单个齿轮当量传动误差与当量空程误差的概念。

关键词：齿轮机构精度分析误差

Depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 335-345页

作者： Feng Zhang Chenyang Zhang Linlin Wu Wei Sun hongliang Zhang Jianhua Chen Yong Pei Songjiang Li Engineering Research Center of Ministry of Education for Carbon Emission Reduction in Metal Resource Exploitation and Utilization Hunan International Joint Research Center for Efficient and Clean Utilization of Critical Metal Mineral ResourcesSchool of Minerals Processing and BioengineeringCentral South UniversityChangsha 410083China State Key Laboratory of Mineral Processing Beijing General Research Institute of Mining&MetallurgyBeijing 100160China Hunan Provincial Key Laboratory of Micro&Nano Materials Interfaces Science College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China School of Resources Environment and MaterialsGuangxi UniversityNanning 530004China Department of Chemistry Xiangtan UniversityXiangtan 411105China China Railway Resource Group Co.Ltd Beijing 102300China

The depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite still lacked in-depth ***,the depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite was further systematically investigated with experiments and density functional theory(DFT)*** X-ray photoelectric spectroscopy(XPS)results,DFT calculation results,and frontier molecular orbital analysis indicated that sulfite ions were difficult to be adsorbed on sphalerite surface,suggesting that sulfite ions achieved depression effects on sphalerite through other non-adsorption ***,the oxygen content in the surface of sphalerite treated with sulfite ions in creased,which enhanced the hydrophilicity of the sphalerite and further increased the difference in hydrophilicity between sphalerite and ***,sulfite ions were chelated with lead ions to form PbSO_(3)in *** hydrophilic PbSO_(3)was more easily adsorbed on sphalerite than *** interaction between sulfite ions and lead ions could effectively inhibit the activation of *** addition the UV spectrum showed that after adding sulfite ions,the peak of perxanthate in the sphalerite treated xanthate solution was significantly stronger than that in the galena with xanthate solution,indicating that xanthate interacted more readily with sulfite ions and oxygen mo lecules within the sphalerite system,leading to the formation of ***,sulfite ions hardly depressed the flotation of ga lena and could promote the flotation of galena to some *** study deepened the understanding of the depression mechanism o sulfite ions on sphalerite and Pb^(2+)activated sphalerite.

关键词： sphalerite galena sulfite ion density functional theory depression mechanism

HTPB–异氰酸酯体系的固化反应机理研究进展

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化学推进剂与高分子材料 2012年第4期10卷 1-7,14页

作者：邱磊盛红亮詹国柱上海航天化工应用研究所浙江湖州313000

固体推进剂和衬层配方的固化体系对其本体性能以及两者界面的黏结性能具有非常重要的影响,端羟基聚丁二烯(HTPB)和异氰酸酯是丁羟固体推进剂和衬层固化体系中最主要的组分。综述了HTPB-异氰酸酯体系的固化反应机理以及催化剂、固化剂种... 详细信息

固体推进剂和衬层配方的固化体系对其本体性能以及两者界面的黏结性能具有非常重要的影响,端羟基聚丁二烯(HTPB)和异氰酸酯是丁羟固体推进剂和衬层固化体系中最主要的组分。综述了HTPB-异氰酸酯体系的固化反应机理以及催化剂、固化剂种类和固化参数等因素对固化反应的影响。

关键词： HTPB 异氰酸酯固化反应机理界面黏结

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端羟基聚丁二烯中羟基类型的NMR研究进展

化学推进剂与高分子材料 2012年第2期10卷 14-18,23页

作者：郝利峰孙庆锋盛红亮上海航天技术研究院第八〇六所浙江湖州313000

介绍了核磁共振(NMR)研究端羟基聚丁二烯(HTPB)中羟基类型的进展,给出了自由基聚合法合成HTPB中涉及的反应机理,总结了HTPB的羟基类型和力学性能的相互关系,并为解决HTPB指标相同、批次不同而性能有很大差异的问题提供了一个基本思路和... 详细信息

介绍了核磁共振(NMR)研究端羟基聚丁二烯(HTPB)中羟基类型的进展,给出了自由基聚合法合成HTPB中涉及的反应机理,总结了HTPB的羟基类型和力学性能的相互关系,并为解决HTPB指标相同、批次不同而性能有很大差异的问题提供了一个基本思路和方法。

关键词：端羟基聚丁二烯核磁共振 NMR 羟基

Impulse feature extraction method for machinery fault detection using fusion sparse coding and online dictionary learning

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Chinese Journal of Aeronautics 2015年第2期28卷 488-498页

作者： Deng Sen Jing Bo sheng sheng Huang Yifeng Zhou hongliang Aeronautics and Astronautics Engineering College Air Force Engineering University Unit 94371 of People's Liberation Army

Impulse components in vibration signals are important fault features of complex machines. Sparse coding （SC） algorithm has been introduced as an impulse feature extraction method, but it could not guarantee a satisfactory performance in processing vibration signals with heavy background noises. In this paper, a method based on fusion sparse coding （FSC） and online dictionary learning is proposed to extract impulses efficiently. Firstly, fusion scheme of different sparse coding algorithms is presented to ensure higher reconstruction accuracy. Then, an improved online dictionary learning method using FSC scheme is established to obtain redundant dictionary and it can capture specific features of training samples and reconstruct the sparse approximation of vibration signals. Simulation shows that this method has a good performance in solving sparse coefficients and training redundant dictionary compared with other methods. Lastly, the proposed method is further applied to processing aircraft engine rotor vibration signals. Compared with other feature extraction approaches, our method can extract impulse features accurately and efficiently from heavy noisy vibration signal, which has significant supports for machinery fault detection and diagnosis.

关键词： Dictionary learning Fault detection Impulse feature extraction Information fusion Sparse coding

Size-and temperature-dependent Young's modulus and size-dependent thermal expansion coefficient of nanowires

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Science China(Technological Sciences) 2018年第5期61卷 687-698页

作者： SUN hongliang CHEN LiuYan SUN sheng ZHANG Tong-Yi Materials Genome Institute Shanghai University and Shanghai Materials Genome Institute

Nanowires(NWs) exhibit size-dependent mechanical properties due to the high surface/volume ratio, in which temperature also plays an important role. The surface eigenstress model is further developed here to quantitatively predict the size-dependent mechanical properties of NWs and results in analytic formulas. Molecular dynamics(MD) simulations are conducted to study the size-dependent mechanical of [100], [110] and [111] Ni and Si nanowires within the temperature range of 100–400 K and the MD results verify perfectly the newly developed surface eigenstress model.

关键词： surface eigenstress model size-and temperature-dependent Young's modulus size-dependent thermal expansion coefficient nanowires molecular dynamics simulations

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厂房机器振动的砂袋垫层减振试验研究

水资源与水工程学报 2017年第6期28卷 190-193页

作者：金红亮盛涛王卫国肖畅宁波大学建筑工程与环境学院浙江宁波315211 浙江大学建筑工程学院浙江杭州310058 宁波建工工程集团有限公司浙江宁波315040

以某5层工业厂房为原型,建立其1/8缩尺模型,以砂袋作为机器设备的减振垫层,开展工业厂房结构机器竖向振动的减振试验,分析砂袋垫层对提高结构安全性和舒适度的有效性。激振试验的结果表明:砂袋垫层具有竖向宽频减振特性,对于机器所在楼... 详细信息

以某5层工业厂房为原型,建立其1/8缩尺模型,以砂袋作为机器设备的减振垫层,开展工业厂房结构机器竖向振动的减振试验,分析砂袋垫层对提高结构安全性和舒适度的有效性。激振试验的结果表明:砂袋垫层具有竖向宽频减振特性,对于机器所在楼层及相邻楼层的位移峰值均具有减振效果,有助于提高厂房结构的安全性;增加砂袋的叠放层数时,可提高竖向振动的减振效果;砂袋垫层有助于提高厂房结构的室内舒适度,使用砂袋垫层后楼板的竖向振动1/3倍频程分频振级最大可减小22 d B。

关键词：机器振动砂袋垫层减振厂房安全舒适度

Evaluation of a resoruf in-based fluorescent probe for tyrosinase detection in skin pigmentation disorders

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Bio-Design and Manufacturing 2021年第4期4卷 806-817页

作者： Yibo Hu hongliang Zeng Jiaxing Jiang sheng Yang Jinhua Huang Jing Chen Qinghai Zeng Department of Dermatology The Third Xiangya Hospital of Central South UniversityTongzipo Road No.138Yuelu DistrictChangsha 410013China Institute of Chinese Materia Medica Hunan Academy of Chinese MedicineChangsha 410006China School of Chemistry and Food Engineering Changsha University of Science and Technology(CSUST)Changsha 410114China

Purpose Skin pigmentation disorders,such as vitiligo and melasma,are difficult to diagnose in the early stages,but abnor-mal tyrosinase levels and tyrosinase activity are potential *** resorufin-based fluorescence probes(RBFPs)have been designed to detect tyrosinase in tumors,but they have not been used in skin pigmentation *** this study,one of these RBFPs(synthesized by resorufin salt coupled with 3-(bromomethyl)phenol)was evaluated *** The RBFP was tested in different kinds of mouse and human skin cells,as well as in in vivo models,including zebrafish,guinea pigs,and Sprague-Dawley *** addition,small interfering RNAs(siRNAs),kojic acid,and 1-phenyl-2-thiourea(PTU)were used to inhibit tyrosinase levels or tyrosinase *** This probe successfully detected tyrosinase and emitted red fluorescence in melanoma cells and *** was also observable in zebrafish and on the skin of guinea pigs when using the *** mouse and human cells,the RBFP showed good selectivity to ***,in the case of decreased tyrosinase levels or activity caused by siRNAs,kojic acid,or PTU,the probe was sensitive to these ***,the RBFP showed no toxic effects at concentrations of<20μmol/L,both in vitro and in *** Our findings indicate the value and limitations of the RBFP in tyrosinase detection,but suggest the need for further improvement of fluorescent probes in the diagnosis of skin pigmentation disorders.

关键词： Tyrosinase Pigmentation disorder Diagnosis Fluorescence probe

Steering structural mesoporosity and working microenvironment of Fe-N-C catalysts for boosting cathodic mass transport of zinc-air batteries

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Science China Chemistry 2022年第8期65卷 1670-1678页

作者： Hang Shen Yanyan Jia Yanbin Qi sheng Dai hongliang Jiang Yihua Zhu Chunzhong Li Shanghai Engineering Research Center of Hierarchical Nanomaterials School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China Key Laboratory for Ultrafine Materials of Ministry of Education School of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center Institute of Fine ChemicalsSchool of Chemistry&Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

Transition metal-N-C materials have considerably been demonstrated as promising catalysts for cathodic oxygen reduction reaction(ORR)in Zn-air *** efforts mainly focus on tailoring coordination structure and identifying active sites of metal-N-C materials for ORR,while the mass transport of metal-N-C employed in catalytic layers of working electrodes is seldom ***,a Fe-N-C single-atom catalyst featuring high mesoporosity and abundant electrochemically accessible active sites is developed through post-loading Fe species into defective N-doped carbon *** Fe-N-C single-atom catalyst serving as the air cathode of Zn-air battery delivers a peak power density of 189.9 mW cm^(−2),significantly larger than 114.2 mW cm^(−2) of commercial Pt/C and 162.9 mW cm^(−2) of the Fe-N-C contrast catalyst with low *** importantly,through adding hydrophobic polytetrafluoroethylene(PTFE)nanoparticles in the catalytic layer of air cathode,the peak power density of Fe-N-C single-atom catalyst is further increased to 212.3 mW cm^(−2).The increased peak power density is attributed to the enhancement of O_(2) mass transport,as evidenced by a substantially decreased diffusion layer thickness that is obtained from electrochemical impedance spectroscopy.

关键词： electrocatalysis oxygen reduction reaction single-atom catalyst mass transport Zn-air batteries