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CR 200J用树脂基摩擦材料的正交试验及多指标加权优选

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润滑与密封 2024年第3期49卷 175-182页

作者：孙辉王秀飞陈少华尹彩流蒙洁丽广西民族大学材料与环境学院广西先进结构材料与碳中和重点实验室广西南宁530105 广西民族大学材料与环境学院广西高校环境友好材料及碳中和新技术重点实验室广西南宁530105 北京优材百慕航空器材有限公司北京100095

为制备CR 200J用高耐磨树脂基摩擦材料,采用正交试验法设计不同含量的减摩组分(鳞片石墨、石油焦)与增摩组分(NFJ高温黏结剂、腰果壳油摩擦粉)的树脂基摩擦材料配方。通过热压成型法制备出样品,在制动压力0.8 MPa和转速3300、4200、5400... 详细信息

为制备CR 200J用高耐磨树脂基摩擦材料,采用正交试验法设计不同含量的减摩组分(鳞片石墨、石油焦)与增摩组分(NFJ高温黏结剂、腰果壳油摩擦粉)的树脂基摩擦材料配方。通过热压成型法制备出样品,在制动压力0.8 MPa和转速3300、4200、5400 r/min下测试试样的平均摩擦因数,并计算试样的体积磨损率、热衰退性能及对偶质量磨损。对试样的平均摩擦因数、体积磨损率、热衰退性能及对偶质量磨损进行极差分析及均一化处理,使用多指标权重优选了综合性能优异的配方。结果表明:鳞片石墨在高转速下对材料的平均摩擦因数起稳定作用及降低材料的热衰退性能,而石油焦在低速制动过程中可稳定材料的平均摩擦因数;NFJ高温黏结剂对材料的各项性能影响不显著,而腰果壳油摩擦粉在高转速下表现出优异的黏弹性,有利于提高材料的平均摩擦因数,降低材料的体积磨损率及对偶质量磨损。使用多指标权重优选得到较好的配方,其中鳞片石墨、石油焦、NFJ高温黏结剂、腰果壳油摩擦粉的质量分数分别为1%、4%、3%、6%。

关键词：树脂基摩擦材料摩擦磨损性能正交试验法多指标权重优选热衰退性能

Interfacial behavior of a thermoelectric film bonded to a graded substrate

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Applied Mathematics and Mechanics(English Edition) 2023年第11期44卷 1853-1870页

作者： Juan PENG Dengke LI Zaixing HUANG Guangjian PENG Peijian chen shaohua chen School of Materials Science and Physics State Key Laboratory for Geomechanics and Deep Underground EngineeringSchool of Mechanics and Civil EngineeringChina University of Mining and TechnologyXuzhou 221116Jiangsu ProvinceChina State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310014China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Institute of Advanced Structure Technology Beijing Institute of TechnologyBeijing 100081China Beijing Key Laboratory of Lightweight Multi-functional Composite Materials and Structures Beijing Institute of TechnologyBeijing 100081China Collaborative Innovation Center of Electric Vehicles in Beijing Beijing Institute of TechnologyBeijing 100081China

To improve the thermoelectric converting performance in applications such as power generation,reutilization of heat energy,refrigeration,and ultrasensitive sensors in scramjet engines,a thermoelectric film/substrate system is widely designed and applied,whose interfacial behavior dominates the strength and service life of thermoelectric ***,a theoretical model of a thermoelectric film bonded to a graded substrate is *** interfacial shear stress,the normal stress in the thermoelectric film,and the stress intensity factors affected by various material and geometric parameters are comprehensively *** is found that adjusting the inhomogeneity parameter of the graded substrate,thermal conductivity,and current density of the thermoelectric film can reduce the risk of interfacial failure of the thermoelectric film/graded substrate *** a stiffer and thicker thermoelectric film is advantageous to the reliability of the thermoelectric film/graded substrate *** results should be of great guiding significance for the present and upcoming applications of thermoelectric materials in various fields.

关键词： thermoelectric film graded substrate interfacial behavior singular integral equation shear stress intensity factor

Dispersive behavior of high frequency Rayleigh waves propagating on an elastic half space

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Acta Mechanica Sinica 2021年第4期37卷 562-569,I0001页

作者： Ning Jia Zhilong Peng Jianjun Li Yin Yao shaohua chen Institute of Advanced Structure Technology Beijing Institute of TechnologyBeijing 100081China Beijing Key Laboratory of Lightweight Multi-Functional Composite Materials and Structures Beijing Institute of TechnologyBeijing 100081China School of Mechanical and Electrical Engineering Central South UniversityChangsha 410083China

When the wavelength of Rayleigh wave is comparable with nanometers,Rayleigh wave will become *** an interesting phenomenon cannot be predicted by the classical theory of *** order to reveal the internal mechanism and influencing factors of the dispersion,a model of Rayleigh wave propagating on an elastic half space is established and analyzed by a new theory of surface elastodynamics,in which the surface effect characterized by both the surface energy density and surface inertia is *** intrinsic nano-length scales,including the ratio of bulk surface energy density to bulk shear modulus and the ratio of surface mass density to bulk mass density,are *** is found that when the wavelength of Rayleigh wave is comparable with the two intrinsic nano-lengths,the surface effect becomes *** a result,dispersion of Rayleigh wave happens and even two Rayleigh waves with different wave speeds may ***,it is found that the effect of surface energy density would enhance the wave speed,while that of surface inertia would reduce *** the increase of wavelength,both effects gradually disappear and the Rayleigh wave speed degenerates to the classical *** results of this paper are not only helpful to understand the dispersive mechanism of elastic waves,but also helpful for the fine design and measurement of nanowave devices.

关键词： Rayleigh wave High frequency Dispersion Elastodynamics Surface effect

Hierarchically porous zeolites synthesized with carbon materials as templates

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Frontiers of Chemical Science and Engineering 2021年第6期15卷 1444-1461页

作者： Huan Wang Guo Du Jiaqing Jia shaohua chen Zhipeng Su Rui chen Tiehong chen Institute of New Catalytic Materials Science School of Materials Science and EngineeringKey Laboratory of Advanced Energy Materials Chemistry(MOE)Nankai UniversityTianjin300350China

Hierarchically porous zeolites are promising candidates in catalytic conversion of relatively bulky molecules,and their syntheses have attracted significant *** both industrial and scientific perspectives,different carbon materials have been widely employed as hard templates for the preparation of hierarchically porous zeolites during the past two *** this review,the progress in synthetic strategies using carbon materials as templates is comprehensively *** on the affinity between the carbon templates and zeolite precursors,the substantial strategies for synthesizing hierarchical zeolites are introduced in direct templates and indirect *** templates methods,by which the carbon materials are directly mixed with precursors gel as hard templates,are first ***,we discuss the indirect templates method(crystallization of carbon-silica composites),by which the carbon is produced by in situ pyrolysis of organic-inorganic *** addition,the technique of encapsulating metal species into zeolites crystals with the assistance of carbon templates is also *** the conclusion part,the factors affecting the synthesis of carbon-templated hierarchically porous zeolites are *** review is expected to attract interest in the synthesis strategies of hierarchically porous zeolites,especially cost-effective and large-scale production methodologies,which are essential to the industrial application of hierarchical zeolites.

关键词： hierarchical zeolites carbon materials direct templates indirect templates carbon-silica composites

甲强龙与阿奇霉素联合用药在小儿重症肺炎支原体肺炎中的应用及对机体炎症的影响分析

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中外医疗 2024年第20期43卷 116-119页

作者：傅敏张光林陈少华福建省三明市第二医院儿科福建三明366000

目的研讨甲强龙与阿奇霉素联合用药在小儿重症肺炎支原体肺炎(Mycoplasma Pneumoniae Pneumonia,MPP)中的应用及对机体炎症的影响。方法简单随机选取2021年2月—2024年2月三明市第二医院收治的50例小儿重症MPP患儿作为研究对象,结合随... 详细信息

目的研讨甲强龙与阿奇霉素联合用药在小儿重症肺炎支原体肺炎(Mycoplasma Pneumoniae Pneumonia,MPP)中的应用及对机体炎症的影响。方法简单随机选取2021年2月—2024年2月三明市第二医院收治的50例小儿重症MPP患儿作为研究对象,结合随机数字表法进行分组,各25例。对照组患儿单纯予以阿奇霉素用药,观察组患儿在对照组用药基础上施加甲强龙静脉滴注,对比两组患儿的用药效果、肺炎症状控制时间、机体炎症状况以及用药不良反应发生情况。结果观察组患儿总有效率(100.00%)高于对照组(76.00%),差异有统计学意义(χ^(2)=4.734,P=0.029)。观察组患儿肺炎症状(发热、咳嗽与肺部啰音)控制时间均短于对照组,差异有统计学意义(P均0.05)。结论甲强龙及阿奇霉素联合用药可提升对小儿重症MPP的治疗效果,加快缓解肺炎症状,减轻机体炎症反应,同时保障用药安全。

关键词：小儿重症肺炎支原体肺炎甲强龙阿奇霉素机体炎症

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一种气体电化学传感器补偿电路的研究与应用

中国仪器仪表 2024年第4期 66-70页

作者：陈正达付聪陈少华宫睿陈登举杭州泽天春来科技股份有限公司浙江杭州310053

为了改善电化学传感器在测量高精度场合存在的误差,本文提出了一种基于差分检测的补偿测量方式,利用电流偏置电路、流压转换电路,调零电路,消除运放本身所产生的失调误差。利用增加补偿零点电流电化学传感器与传统地电极电化学传感器进... 详细信息

为了改善电化学传感器在测量高精度场合存在的误差,本文提出了一种基于差分检测的补偿测量方式,利用电流偏置电路、流压转换电路,调零电路,消除运放本身所产生的失调误差。利用增加补偿零点电流电化学传感器与传统地电极电化学传感器进行对比实验,实验表明通过补偿电路也可以有效地解决了电路本身所产生的偏差,保证电化学传感器能正常且迅速地工作,保证信号检测的稳定性。

关键词：电化学传感器高精度补偿电路

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基于扩展有限元、内聚力单元和单元失效的受弯钢筋混凝土梁数值模拟分析

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常州工学院学报 2024年第3期37卷 31-38页

作者：陈少华齐益李双江苏州科技大学土木工程学院江苏苏州215011

利用Abaqus中扩展有限元法、内聚力单元和显示动力分析模块下单元失效分析钢筋混凝土梁的受弯响应,对比混凝土4点受弯梁试验和有限元分析的整体性能、损伤与失效,提出混凝土的精细化建模方法。根据模拟结果可知:扩展有限元法和内置内聚... 详细信息

利用Abaqus中扩展有限元法、内聚力单元和显示动力分析模块下单元失效分析钢筋混凝土梁的受弯响应,对比混凝土4点受弯梁试验和有限元分析的整体性能、损伤与失效,提出混凝土的精细化建模方法。根据模拟结果可知:扩展有限元法和内置内聚力单元模拟混凝土整体性能和拉裂行为精度较高;扩展有限元法模拟的混凝土裂纹扩展路径自由,适合对受力或相互作用复杂的混凝土进行精细化建模与损伤分析;内置内聚力单元的裂纹形成与扩展依赖单元网格密度与形状,适合在相关理论成熟或试验数据全面的基础上做影响参数分析;设置单元失效准则可同时模拟混凝土的压溃和拉裂行为,但损伤发展较快,精度偏低。

关键词：混凝土损伤扩展有限元内聚力单元单元失效钢筋混凝土梁

基于腔减相移光谱技术低浓度NO_(2)监测的研究

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中国仪器仪表 2024年第6期 35-39页

作者：陈少华陈正达郭杰陈登举张腾杭州泽天春来科技股份有限公司浙江杭州310053

空气中NO_(2)浓度比较低,监测方法分辨率需要低至十亿分之一水平。因此,对监测设备检测的下限、线性度及稳定性都有更高有要求。为了解决低浓度NO_(2)测量方法存在的不足,本文研究基于腔减相移光谱(CAPS)技术在低浓度NO_(2)的测量应用... 详细信息

空气中NO_(2)浓度比较低,监测方法分辨率需要低至十亿分之一水平。因此,对监测设备检测的下限、线性度及稳定性都有更高有要求。为了解决低浓度NO_(2)测量方法存在的不足,本文研究基于腔减相移光谱(CAPS)技术在低浓度NO_(2)的测量应用。为有效评估检测能力和综合应用情况,研究中搭建了一套基于CAPS技术的大气NO_(2)浓度测量的CPAS系统,同时选用基于国家标准方法(化学发光法)的澳大利亚ECOTECH的Serinus 40型分析仪作为参比设备,在相同的自然环对空气中NO_(2)进行连续7天的实时测量,并将测量结果和国控点数据进行比较分析。经过测量,CPAS系统检测下限0.025ppb,低于Serinus 40的0.4ppb;7天测量的线性度达到了99.99%。证明CAPS技术满足在低浓度NO_(2)监测需求。

关键词：环境气体监测二氧化氮光腔衰减相移法化学发光法

Occurrence of veterinary antibiotics in struvite recovery from swine wastewater by using a fluidized bed

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Frontiers of Environmental Science & Engineering 2018年第3期12卷 99-105页

作者： Zhi-Long Ye Yujun Deng Yaoyin Lou Xin Ye shaohua chen Key Laboratory of Urban Pollutant Conversion Institute of Urban Environment Chinese Academy of Sciences Xiarnen 361021 China

Recovering phosphorus from livestock wastewater has gained extensive attention. The residue of veterinary antibiotics in the wastewater may be present in the recovered products, thereby posing pharmacological threats to the agricultural planting and human health. This study investigated antibiotic occurrence in the struvite particles recovered from swine wastewater by using a fluidized bed. Results revealed that tetracyclines possessed significant residues in the struvite granules, with the values ranging from 195.2μ***^-1 to 1995.0 μ***^-1. As for fluoroquinolones, their concentrations varied from 0.4μg·kg^-1 to 1104.0 μg·kg^-1. Struvite particles were of various sizes and. shapes and displayed different antibiotic adsorption capacities. The data also showed that the smaller granules contained much more antibiotics than the larger ones, indicating that the fluidized granulation process of struvite crystals plays an important role on the accumulation of antibiotics. For tetracyclines, organic matters and struvite adsorption exerted significant impacts on tetracyclines migration. The outcomes underscore the need to consider the residues of antibiotics in resource recovery from wastewater because they exert pharmacological impacts on the utilization of recovered products.

关键词： Antibiotic Struvite Phosphorus recovery Swine wastewater Fluidized bed