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1.
以17CrNiMo6钢渗碳齿轮为例,首先制备了不同程度的磨削烧伤试样,并依据酸洗法和金相法对其进行磨削烧伤级别分类;然后通过建立不同磨削烧伤级别齿面磁弹法所测特征值MP与其表层显微硬度、残余应力的对应关系曲线,验证了磁弹法能够对渗碳齿轮的磨削烧伤做出准确评价,并使用该方法对不同磨削烧伤等级进行了量化表征。在此基础上,将磁弹法检测纳入实际生产检验流程中,实现了渗碳齿轮磨削烧伤的在线检测。  相似文献   

2.
综述了齿轮磨削烧伤的各种检测方法及应用特点,主要包括观色法、酸蚀法、表层显微硬度试验法、残余应力测定法、金相检测法和磁弹法。通过比较得出:传统的磨削烧伤检测方法存在对工件造成破坏、检测效率低等弊端,无法满足快速、高效的现代检测要求;而磁弹法具有操作简单、方便、高效且无损等优点,在齿轮产品表面磨削烧伤检测中具有广阔的应用前景。  相似文献   

3.
电容位移法精确测量磁性薄膜的磁致伸缩系数   总被引:8,自引:1,他引:7  
万红  邱佚  谢海涛  斯永敏  扬德明 《功能材料》2002,33(3):262-263,266
介绍了一种精确测量磁性薄膜磁致伸缩系数方法-电容位移法,并自行研制组装了一套测量装置,通过误差分析,仪器的精确标定,对稀土-铁超磁致伸缩薄膜的磁致伸缩系数进行了测量,获得满意的结果。  相似文献   

4.
本文针对太原大唐第二热电厂3台机纽末级再热器炉顶穿墙管爆漏的严重情况,应用金属磁记忆无损捡测技术对爆管原因进行分析,为此,介绍了金属磁记忆无损检测技术的原理,检测仪器、检测方法;比较分析了金属磁记忆无损检测技术和传统无损检测技术的根本区别,指出磁记忆检验是这类爆漏管子事故早期诊断并实现状态检修的有效手段。  相似文献   

5.
本文主要介绍了对EXCELL2000套管接箍磁定位测井仪进行的功能扩展,通过增加转换短衿等方法,束替换国产HH2530数控测井系统仪器串中磁定位的位置。通过改进延伸了EXCELL2000磁定位测井仪的工作范围,满足了两种测井标准要求,提高了EXCE1.L2000磁定位测井仪的利用率和价值。  相似文献   

6.
基于激光位移法建立了一套大磁致伸缩材料测量装置,可以实现磁致伸缩系数的无接触、整体、准确测量。仪器测量磁致伸缩系数的复现性可达到2%。使用该装置测量不具有磁致伸缩性能的材料,结果显示仪器系统误差仅为3×10~(-6);装置测量纯镍样品饱和磁致伸缩系数的结果与理论值吻合良好。  相似文献   

7.
动态磁性能测试仪的研究   总被引:3,自引:0,他引:3  
研制出频率范围50Hz~50kHz的动态磁性能测量仪样机,该仪器是基于16位微处理器的便携式仪器,包含信号源、功率放大器、电压表、电流表和功率表。采用准同步采样方法和数值积分算法,计算磁滞回线和损耗、磁导率等参数  相似文献   

8.
本文主要论述了我国磁参量计量标准的发展现状,磁量具和磁测仪器的检定条件,并且介绍了二等磁参量计量标准的组成和技术指标。  相似文献   

9.
本文主要论述了我国磁参量计量标准的发展现状,磁量具和磁测仪器的检定条件,并且介绍了二等磁参量计量标准的组成和技术指标。  相似文献   

10.
本文主要论述了目前我国磁参量计量标准装置及技术标准的发展现状,磁量具和磁测仪器的检定条件以及二等磁参量计量标准装置的组成和技术指标。  相似文献   

11.
Bleeding complications arising from trauma, surgery, and as congenital, disease‐associated, or drug‐induced blood disorders can cause significant morbidities and mortalities in civilian and military populations. Therefore, stoppage of bleeding (hemostasis) is of paramount clinical significance in prophylactic, surgical, and emergency scenarios. For externally accessible injuries, a variety of natural and synthetic biomaterials have undergone robust research, leading to hemostatic technologies including glues, bandages, tamponades, tourniquets, dressings, and procoagulant powders. In contrast, treatment of internal noncompressible hemorrhage still heavily depends on transfusion of whole blood or blood's hemostatic components (platelets, fibrinogen, and coagulation factors). Transfusion of platelets poses significant challenges of limited availability, high cost, contamination risks, short shelf‐life, low portability, performance variability, and immunological side effects, while use of fibrinogen or coagulation factors provides only partial mechanisms for hemostasis. With such considerations, significant interdisciplinary research endeavors have been focused on developing materials and technologies that can be manufactured conveniently, sterilized to minimize contamination and enhance shelf‐life, and administered intravenously to mimic, leverage, and amplify physiological hemostatic mechanisms. Here, a comprehensive review regarding the various topical, intracavitary, and intravenous hemostatic technologies in terms of materials, mechanisms, and state‐of‐art is provided, and challenges and opportunities to help advancement of the field are discussed.  相似文献   

12.
《工程(英文)》2018,4(4):574-580
Organic solid and liquid wastes contain large amounts of energy, nutrients, and water, and should not be perceived as merely waste. Recycling, composting, and combustion of non-recyclables have been practiced for decades to capture the energy and values from municipal solid wastes. Treatment and disposal have been the primary management strategy for wastewater. As new technologies are emerging, alternative options for the utilization of both solid wastes and wastewater have become available. Considering the complexity of the chemical, physical, and biological properties of these wastes, multiple technologies may be required to maximize the energy and value recovery from the wastes. For this purpose, biorefining tends to be an appropriate approach to completely utilize the energy and value available in wastes. Research has demonstrated that non-recyclable waste materials and bio-solids can be converted into usable heat, electricity, fuel, and chemicals through a variety of processes, and the liquid waste streams have the potential to support crop and algae growth and provide other energy recovery and food production options. In this paper, we propose new biorefining schemes aimed at organic solid and liquid wastes from municipal sources, food and biological processing plants, and animal production facilities. Four new breakthrough technologies—namely, vacuum-assisted thermophilic anaerobic digestion, extended aquaponics, oily wastes to biodiesel via glycerolysis, and microwave-assisted thermochemical conversion—can be incorporated into the biorefining schemes, thereby enabling the complete utilization of those wastes for the production of chemicals, fertilizer, energy (biogas, syngas, biodiesel, and bio-oil), foods, and feeds, and resulting in clean water and a significant reduction in pollutant emissions.  相似文献   

13.
MXene, an important and increasingly popular category of postgraphene 2D nanomaterials, has been rigorously investigated since early 2011 because of advantages including flexible tunability in element composition, hydrophobicity, metallic nature, unique in‐plane anisotropic structure, high charge‐carrier mobility, tunable band gap, and favorable optical and mechanical properties. To fully exploit these potentials and further expand beyond the existing boundaries, novel functional nanostructures spanning monolayer, multilayer, nanoparticles, and composites have been developed by means of intercalation, delamination, functionalization, hybridization, among others. Undeniably, the cutting‐edge developments and applications of clay‐inspired 2D MXene platform as electrochemical electrode or photo‐electrocatalyst have conferred superior performance and have made significant impact in the field of energy and advanced catalysis. This review provides an overview of the fundamental properties and synthesis routes of pure MXene, functionalized MXene and their hybrids, highlights the state‐of‐the‐art progresses of MXene‐based applications with respect to supercapacitors, batteries, electrocatalysis and photocatalysis, and presents the challenges and prospects in the burgeoning field.  相似文献   

14.
Two‐dimensional materials are responsible for changing research in materials science. After graphene and its counterparts, graphane, fluorographene, and others were introduced, waves of renewed interest in 2D binary compounds occurred, such as in metal oxides, transition‐metal dichalcogenides (most often represented by MoS2), metal oxy/hydroxide borides, and MXenes, to name the most prominent. Recently, interest has turned to two‐dimensional monoelemental structures, such as monolayer black phosphorus and, very recently, to monolayer arsenic, antimony, and bismuth. Here, a short overview is provided of the area of exponentially increasing research in arsenene, antimonene, and bismuthene, which belong to the fifth main group of elements, the so‐called pnictogens. A short review of historical work is provided, the properties of bulk allotropes of As, Sb, and Bi discussed, and then theoretical and experimental research on mono‐ and few‐layered arsenene, antimonene, and bismuthene addressed, discussing their structures and properties.  相似文献   

15.
In 1985, the CODATA Bulletin published a Report of its Task Group on Thermophysical Properties of Solids which analyzed available data on, and gave recommended values for, the heat capacity of Cu, Fe, W, and Al2O3, the thermal expansion of Cu, Si, W, and Al2O3, the electrical resistivity of Cu, Fe, Pt, and W, the thermal conductivity of Al, Cu, Fe, and W, and the absolute thermopower of Pb, Cu, Pt, and W. The analysts for the different properties were R. B. Castanet, S. J. Collocott, P. D. Desai, C. Y. Ho, J. G. Hust, R. B. Roberts, C. A. Swenson, and G. K. White. The present paper is an updated version of the earlier report and includes more recent data which change some of the recommended values. notably the heat capacity of Cu and W and the thermal expansion of Si and W.  相似文献   

16.
Neurotechnology applies methods and devices to mitigate the burden of neurological and mental disorders. In particular, neural interfaces establish a long-term, seamless, symbiotic integration between implants and neural tissue. Materials play a pivotal role in neurotechnology. Advanced materials and materials engineering are crucial to achieving the desired function and outcome. Recently, neural interfaces extended their range of applications with the emergence of flexible, conformable, stretchable, injectable, and transient electronics. However, despite this enormous advancement in materials science and engineering, clinical devices still rely on old-fashioned but reliable materials and processes. The gap between research development and industry adoption has recently gained high interest. This article analyzes recent developments, discusses roadblocks, and provides a roadmap for materials engineering applied to neurotechnology.  相似文献   

17.
The evolution of approaches to the solution of machine dynamics and strength problems on the basis of determining static and dynamic nominal and local stresses of the operating load is discussed. It is shown how the material strength and plasticity characteristics, the cyclic strength characteristics in the high-cycle and low-cycle fatigue regions, the high-temperature long-term strength and creep characteristics, and the linear and nonlinear characteristics of fracture mechanics were sequentially used as the basic criterial parameters of the deformability and strength of structural materials. Particular emphasis was given to the results of studies on machine safety and catastrophe mechanics. Integrated approaches to the solution of strength and safety problems of potentially dangerous facilities (nuclear power stations, spacecraft complexes, aircraft, chemical plants, etc.) by analysis of all stages of their life cycle, including design, manufacture, testing, and operation, are discussed.  相似文献   

18.
黄慧  陈雨 《无机材料学报》2022,37(11):1151-1169
临床医学和生物材料的蓬勃发展, 促进了多种疾病的诊断成像、有效治疗和精准诊疗。材料与医学交叉学科(简称“材料医学”)的发展旨在克服传统临床医学面临的主要障碍和挑战, 如系统性毒性、生物利用度差、靶向部位特异性低、诊断/治疗效果不理想等。本文系统地阐述了近年来各种医学材料在疾病诊断、治疗和诊疗方面的应用进展, 特别是纳米医学材料的研究进展。首先, 重点讨论癌症治疗领域的生物医学成像(如光学成像、磁共振成像、超声成像、计算机断层成像等)和治疗策略(如光热治疗、动力学治疗、免疫治疗、协同治疗等)。此外, 我们还重点介绍了医学材料对骨组织工程、呼吸系统、中枢神经系统等疾病的诊断和治疗的最新进展, 并重点阐述了用于生物传感和抗微生物等其他代表性生物医学领域的医学材料。最后, 我们讨论了这些独特的医学材料在实际临床转化和应用中所面临的挑战和未来的机遇, 以促进其早日实现临床转化, 推动医学进步和造福患者。  相似文献   

19.
In response to the marked increase in research activity and publications in multifunctional materials and structures in the last few years, this article is an attempt to identify the topics that are most relevant to multifunctional composite materials and structures and review representative journal publications that are related to those topics. Articles covering developments in both multiple structural functions and integrated structural and non-structural functions since 2000 are emphasized. Structural functions include mechanical properties like strength, stiffness, fracture toughness, and damping, while non-structural functions include electrical and/or thermal conductivity, sensing and actuation, energy harvesting/storage, self-healing capability, electromagnetic interference (EMI) shielding, recyclability and biodegradability. Many of these recent developments are associated with polymeric composite materials and corresponding advances in nanomaterials and nanostructures, as are many of the articles reviewed. The article concludes with a discussion of recent applications of multifunctional materials and structures, such as morphing aircraft wings, structurally integrated electronic components, biomedical nanoparticles for dispensing drugs and diagnostics, and optically transparent impact absorbing structures. Several suggestions regarding future research needs are also presented.  相似文献   

20.
本文是作者再次对标准和标准化的概念进行讨论。首先讨论的是标准化的目的、主体和对象。作者认为标准化的目的是控制、有序化和统一化;标准化的主体是人/机构;标准化对象可以是具体的或抽象的事物,也可以是它们的组合;任何事物都可以抽象地表达为实体(entity)。第二,作者讨论了标准和标准化的本质以及它们的作用;认为从内容角度看,标准是匹配问题解决方案,也是为标准化对象规定需要满足的要求;从实施角度看,标准是规则;标准化则是制定、实施、传播标准的过程;标准的作用是能够创建并组织现实世界,并能够为相关方建立互相交流和共同理解的基础;标准化的作用是对创新方案进行选择和简化,阻止现实世界过度无序化发展,形成复杂化和简化之间的平衡。第三,作者讨论了标准的记录形式、自愿/强制属性和时空范围,认为标准的记录形式有文件、样品、图形符号、物理表达等多种形式;标准具有选择的自愿性和实施的强制性;标准在时空范围内是有限的。文章的结尾给出了理解标准化概念的框架。  相似文献   

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