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71.
由于传统的KGLF 11型励磁装置存在不足,为了引导更多矿山企业在设备改造中使用性能更优的新型微机控制KGLF 2型励磁装置,简要介绍了该励磁装置的硬件组成、特点、控制原理以及常见故障的排除方法,以便使业界及时、全面地认识该装置。 相似文献
72.
本文采用二维特征模型模拟不同无燃料区厚度全陶瓷微封装弥散(FCM)燃料的热力学行为,在保证堆芯装载要求的条件下,研究不同结构FCM燃料SiC基体和包覆燃料颗粒SiC层的应力状态。通过优化无燃料区厚度,调整TRISO颗粒间的间距,保证无燃料区和SiC层同时具有较低的应力水平。分析了无燃料区厚度为100 ~ 500 μm时基体SiC、无燃料区以及SiC层的应力分布,结果表明,基体SiC和SiC层最大应力随无燃料区厚度增大而增大,而无燃料区的最大应力则随其厚度增大而降低。当无燃料区厚度为400 μm时,无燃料区和SiC层均处于较低的应力状态,无燃料区SiC基体应力约为400 MPa,而SiC层的最大环向应力约为200 MPa,其失效概率约为2.5×10-4。因此,当无燃料区厚度为400 μm时,FCM燃料既能维持芯块结构完整,又能保证SiC层具有较低的失效概率。结构优化为FCM燃料的应用提供了基础。 相似文献
73.
Liqiang Ren Shujie Yang Peiran Zhang Zhiguo Qu Zhangming Mao Po‐Hsun Huang Yuchao Chen Mengxi Wu Lin Wang Peng Li Tony Jun Huang 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(40)
Microfluidic fluorescence‐activated cell sorters (μFACS) have attracted considerable interest because of their ability to identify and separate cells in inexpensive and biosafe ways. Here a high‐performance μFACS is presented by integrating a standing surface acoustic wave (SSAW)‐based, 3D cell‐focusing unit, an in‐plane fluorescent detection unit, and an SSAW‐based cell‐deflection unit on a single chip. Without using sheath flow or precise flow rate control, the SSAW‐based cell‐focusing technique can focus cells into a single file at a designated position. The tight focusing of cells enables an in‐plane‐integrated optical detection system to accurately distinguish individual cells of interest. In the acoustic‐based cell‐deflection unit, a focused interdigital transducer design is utilized to deflect cells from the focused stream within a minimized area, resulting in a high‐throughput sorting ability. Each unit is experimentally characterized, respectively, and the integrated SSAW‐based FACS is used to sort mammalian cells (HeLa) at different throughputs. A sorting purity of greater than 90% is achieved at a throughput of 2500 events s?1. The SSAW‐based FACS is efficient, fast, biosafe, biocompatible and has a small footprint, making it a competitive alternative to more expensive, bulkier traditional FACS. 相似文献
74.
75.
BEPCⅡ加速器的束流位置测量系统(BPM)模拟电子学经过十余年的运行逐渐老化,故障率上升,亟需进行升级改造。本文根据该需求,自行设计了基于BEPCⅡ系统参数的数字BPM电子学系统,内容包括模拟信号处理电子学、数字信号处理电子学、BPM固件算法逻辑、数据获取软件以及系统测试等多个部分。设计的数字BPM电子学系统经实验板级性能测试、实验室系统测试以及在线束流测试,结果表明该系统能满足BEPCⅡ装置对束流位置测量的需求。 相似文献
76.
77.
Yuanming Wu Xiaohua Chen Li Wang Lunjie Wu Lu Lin Wenwu Ding Zhenming Che Jianfeng Wang Jianzhou Li Yi Liu Weifeng Sun 《International Journal of Food Science & Technology》2020,55(4):1825-1832
Preparation of flavour peptides with microorganisms is an attractive choice for its large-scale production. However, beefy meaty peptide (BMP), as a research hotspot in the field of umami peptide, has been studied in few microorganisms, and furthermore, the safe preparation of BMP has not yet been reported. In this study, multi-copy BMP (8BMP) was successfully expressed and produced in the ‘generally recognized as safe’ Bacillus subtilis (B. subtilis). Firstly, 8BMP with the potentially intense umami was screened out based on molecular docking analysis. Then, it was successfully expressed in the B. subtilis 168 and verified through sensory evaluation. Finally, the scaling capacity of 8BMP was evaluated in a 5-L fermenter, with the highest yield (0.84 g L−1) 6.4 times than that of shake flask, which is conductive for industrial production of BMP and other food peptides. 相似文献
78.
Jianjun Chen Min Jiang Wenxin Lin Lijuan Ding Lipeng Xin 《Journal of Materials Science》2018,53(5):3289-3295
Flexible papers constructed by one-dimensional nanowires have attracted much attention due to their various applications. Herein, a novel nonwoven fabric with paper-like qualities composed of zinc blende SiC (β-SiC) nanowires was fabricated by a scalable rolling process. The SiC nanowires were synthesized by the carbothermal reduction reaction of the carbon fiber and carbonaceous silica xerogel. The crystal phase, morphology and microscopic structure of the as-prepared SiC nanowires were characterized by field emission scanning electron microscope, X-ray diffraction and high-resolution transmission electron microscopy. The nanowire vapor–solid growth mechanism and preparation process for SiC nanowire nonwoven fabric were also discussed. The freestanding SiC nanowire nonwoven fabric exhibited high flexibility, high mechanical strength, excellent refractory performance and thermal stability. With high flexibility, high mechanical strength, superior nonflammability and thermal stability, the flexible paper-like 3C-SiC nanowire nonwoven fabric materials would be expected to have some potential applications, such as ceramic matrix composites, metal matrix composites, energy storage, catalyst supports, radiation-proof fabric, filtration and separation. 相似文献
79.
内蒙古某含银铅锌矿主要含有铅、锌、银、铜、硫等有价元素,对该矿进行系统的工艺矿物学研究,查明矿石的矿物组成、结构与构造,目的矿物的嵌布特征、嵌布粒度、赋存状态等,为制定选矿工艺流程提供矿物学依据。 相似文献
80.
热后硬孔攻丝螺纹变形量小、尺寸稳定、强度高。该工艺方法对刀具强度要求较高,使用普通高速钢丝锥和螺纹铣刀加工时,普通高速钢丝锥无法承受热后硬孔攻丝所产生的大扭矩而频繁折断,报废率较高,同时螺纹铣刀成本高,不适合大批量生产。针对热后硬孔攻丝工艺复杂、成本高的问题,专门设计了硬孔攻丝用高性能先端丝锥,解决硬孔攻丝难题,并与其他种类丝锥进行了切削力对比。 相似文献