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21.
复合吸附剂的吸附性能是吸附制冷循环过程中的一个重要参数,基于测试整体成型复合吸附剂吸附性能的需要,本文设计搭建了一种整体成型吸附剂性能测试装置,对复合吸附剂MgCl_2-13X进行了吸附性能测试实验。结果表明:该实验装置中吸附床外侧底部的温度变化速率较接近吸附床内部底部吸附剂的温度变化速率,二者温度变化速率相差0.01~1.9℃/min,整个吸附和脱附过程二者温度的平均值相差约3.24%,能够满足吸附剂性能测试实验的要求。吸附剂性能测试实验及电镜下吸附剂的微观结构表明:浸泡法制备的复合吸附剂的吸附性能与MgCl_2溶液的浓度有关,MgCl_2能够改善13X沸石分子筛的吸附性能,本实验测得当MgCl_2溶液的浓度为15%时所制得复合吸附剂MX3性能最优,其最大吸附量为0.32 g/g,最大吸附速率0.59 g/min,相比单一吸附剂13X沸石分子筛提高了20%。 相似文献
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The present investigation evaluated the effects of virtual reality (VR) training on the performance, perceived workload and stress response to a live training exercise in a sample of Soldiers. We also examined the relationship between the perceptions of that same VR as measured by engagement, immersion, presence, flow, perceived utility and ease of use with the performance, workload and stress reported on the live training task. To a degree, these latter relationships were moderated by task performance, as measured by binary (Go/No-Go) ratings. Participants who reported positive VR experiences also tended to experience lower stress and lower workload when performing the live version of the task. Thus, VR training regimens may be efficacious for mitigating the stress and workload associated with criterion tasks, thereby reducing the ultimate likelihood of real-world performance failure.
Practitioner Summary: VR provides opportunities for training in artificial worlds comprised of highly realistic features. Our virtual room clearing scenario facilitated the integration of Training and Readiness objectives and satisfied training doctrine obligations in a compelling engaging experience for both novice and experienced trainees. 相似文献
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产品的内涵能源不仅包括产品在生产过程中消耗的能源,还包括产品在加工、运输过程以及消耗原材料中内涵的能源。笔者基于中国2007年投入产出表,利用投入产出方法估算我国42部门内涵能源强度,并依据估算结果计算出我国2007年出口贸易中内涵能源承载量为11.78亿t标准煤,占我国2007年总能源消费的46.42%。 相似文献
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采用等离子体浸没式离子注入对45钢进行氮离子注入。对注入表层的成分、组织和性能进行了分析。研究结果表明:注入层的剖面氮浓度分布呈高斯分布特征,注入层中有大量氮化物相形成,注入层的显微硬度和摩擦性能有明显改善。 相似文献
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As the demand for large capacity storage drives has increased, the flying height of near-field recording (NFR) sliders becomes
as small as 100 nm for super high storage density. Accordingly contamination problems have been a concern of information storage
industry because it may cause a serious damage to solid immersion lens (SIL) of optical flying head. Sub-micro contaminants
in air bearing of the NFR slider may affect the flyability and stability of the optical slider. In addition, the cleaning
of small particles becomes more difficult as the contaminant particle size decreases because the adhesion force increases
very much as the particle size decreases. Recently developed high-frequency ultrasonic (megasonic) cleaning technique have
made it possible to remove sub-micron particles less than 100 nm without surface erosion and many remarkable results have
been reported. In this paper, the megasonic technique is applied and tested for the cleaning of the flying head of NFR drive.
1 MHz ultrasound with maximum 100 W was used to remove polystyrene latex (PSL) particles and alumina particles deposited on
the surface of the slider. Effective cleaning performance was observed without any damages on the slider surface using optical
microscope and AFM at different ultrasonic energy levels and cleaning times.
Received: 20 June 2002 / Accepted: 9 September 2002 相似文献
28.
简要地论述了少胶VPI整浸技术的优点,所采用的主要绝缘材料及其性能要求。重点论述了少胶VPI整浸工艺及定子样棒的实验结果分析。 相似文献
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采用一种新型的等离子体浸没式离子注入技术 (PIII)在渗硼后的 5 0Mn钢试样上制备出了厚度为 0 .15~ 0 .2mm的立方氮化硼 (c BN)表面硬化层。经X射线电子能谱 (XPS)和X射线衍射分析 (XRD) ,发现硬化层中的组织有立方氮化硼 (c BN)、六方氮化硼 (h BN)、B2 O3,FeB和Fe2 B。在表层 60nm的深度范围内 ,c BN的含量较高。采用球盘式无润滑滑动摩擦实验和维氏显微硬度实验分别对渗硼 PIII复合处理以及单独渗硼的 5 0Mn钢试样的性能进行了对比实验。结果表明 :与单独渗硼的试样相比 ,经渗硼 PIII复合处理的试样具有高得多的硬度 (高达HV0 .1N44GPa)和耐磨性 相似文献
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U. Kamachi Mudali H. S. Khatak Baldev Raj M. Uhlemann 《Materials and Manufacturing Processes》2004,19(1):61-73
It is well known that the addition of nitrogen to steels and stainless steels enhances the passivity and localized corrosion resistance, in addition to improving the mechanical properties. Selective alloying of surfaces of steels and stainless steels with nitrogen could also enhance the corrosion resistance and improve the mechanical properties without affecting the bulk properties. Techniques like ion implantation, laser alloying, nitriding, etc. can be effectively used to introduce very high levels of nitrogen. In addition, these techniques can also produce modified surfaces with novel microstructures to further improve the properties. The surface alloying methods also provide an opportunity to selectively nitrogenate the surface of finished components in order to obtain better properties. The review highlights the techniques, modifications and the properties obtained further. 相似文献