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Zhongshan Daxue xuebao. Yixue kexue ban, 2006 [目的]探讨光学相干断层扫描仪（OCT）、超声波角膜测厚仪及OrbscanⅡ角膜地形图/角膜测厚系统（OrbscanⅡ系统）测量中央角膜厚度（CCT）的差异及测量的可重复性.[方法]分别用OCT、超声波角膜测厚仪和OrbscanⅡ系统测量近视患者34例（68只眼）的CCT并对测量值进行比较,用相关分析方法分析不同仪器间测量值的相关性;随机选择15例（30只眼）用三种仪器依次重复测量中央角膜厚度3次,采用方差分析方法分析3种仪器重复测量值的方差.[结果]OCT、超声波角膜测厚仪 ...
曾阳发 +6 more
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Effect of Ultrasonic Treatment on Structure and Antioxidant Activity of Channa argus Short Peptide-Zinc(超声波对乌鳢短肽-锌结构及抗氧化性的影响) [PDF]
Shipin kexue jishu xuebao, 2020 In order to shorten the reaction time and improve the stability of Channa argus short peptide-zinc (CASP-Zn), the ultrasonic technology was employed to analyze the effects of different time (0,5, 10,5, 30,5, 60,5, 90,0min) and different ultrasonic power (
WANG Jingyu(汪婧瑜) +7 more
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Design and Research of Production Line of Continuous Cyclic Ultrasonic Extraction(连续循环超声波提取生产线的设计和研究) [PDF]
Shipin kexue jishu xuebao, 2014 The equipment structure and characteristics of ultrasonic extraction circulation were intro-duced based on the advantages and disadvantages of domestic ultrasonic extraction equipment.
LIU Yude(刘玉德) +4 more
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Zhongguo youzhi, 2023 为提高茶皂苷的提取率，扩大茶皂苷的应用范围，以脱脂油茶籽饼为原料，采用超声-微波辅助法提取茶皂苷。以油茶皂苷提取率为考察指标，在单因素试验的基础上，采用Plackett-Burman试验设计筛选出具有显著影响的试验因素，再通过响应面法对茶皂苷提取工艺进行优化。另外，将超声-微波辅助法提取茶皂苷的工艺与超声辅助法和微波辅助法提取工艺进行了对比。结果表明：超声-微波辅助法提取茶皂苷的最佳工艺条件为乙醇体积分数59%、料液比1∶ 12、提取液pH 7、超声功率475 W、超声时间4 min、超声工作2 ...
司喜艳，王香玉，皇甫新燕，王琦，赵仁勇SI Xiyan, WANG Xiangyu, HUANGFU Xinyan, WANG Qi, ZHAO Renyong
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Study on Water Evaporation of Ultrasonic Vacuum Freeze Drying Yogurt(超声波强化真空冷冻干燥酸奶中水分蒸发的研究) [PDF]
Shipin kexue jishu xuebao, 2014 In this study, ultrasonic and vacuum freeze drying were combined to dry yogurt. Compared with the vacuum freeze drying, the effects of ultrasonic time, power, and pulse on water evaporation and drying time of yogurt were determined. Meanwhile, the drying
YANG Ju-fang(杨菊芳) +4 more
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Analysis on flow characteristics and aerodynamic-force-induced vibration of supersonic rocket-sled
Xibei Gongye Daxue Xuebao, 2022 目前, 火箭橇试验是飞行器空气动力学重要试验手段, 然而强烈的地面与轨道干扰会影响试验的精度, 甚至导致试验失败。采用尺度自适应SAS方法和基于铺层算法的动网格技术对不同马赫数下的超声速火箭橇滑行过程进行数值模拟, 探究了超声速火箭橇的气动力致振机理。采用了数值风洞模拟方法对超声速火箭橇无限空间绕流和仅包含地面的橇体绕流进行仿真, 分析了不同环境条件下的激波特征。结果表明: 超声速火箭橇的头激波传播至轨道和地面时会发生激波反射, 反射激波的存在会导致超声速火箭橇产生升力, 并带来阻力的略微增加 ...
YU Yuanyuan +5 more
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Research on Preparation of Resistant Starch from Lotus Seed by Ultrasonic-Autoclaving(超声波-压热法制备莲子抗性淀粉工艺研究) [PDF]
Shipin kexue jishu xuebao, 2014 Lotus seed native starch was obtained by the wet milling method, and the ultrasonic pretreatment combining autoclaving method was applied to prepare resistant starch.
WU Xiaoting(吴小婷) +4 more
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Gaoya dianqi, 2022 近年来波纹铝护套结构高压电缆中出现的缓冲层烧蚀缺陷造成巨额经济损失和不良社会影响，然而该缺陷产生及发展机理尚不明确，检测技术仍处于探索阶段。文中基于缓冲层间隙放电导致烧蚀缺陷的理论，开展高压电缆缓冲层烧蚀缺陷产生超声信号特征研究，探索超声检测技术在缓冲层烧蚀缺陷检测领域的可行性。文中首先基于高压电缆结构特征以及缓冲层多孔介质特性，建立缓冲层多孔介质波模型以及缓冲层放电产生超声波模型。随后通过数值模型得到缓冲层放电产生超声波声压等效波形以及不同层数缓冲层在不同频率下的吸声系数 ...
何维晟 +6 more
doaj
Optimization of Ultrasonic Assisted Extraction of Pigment from Citrus Peels by Response Surface Methodology(响应面优化柑橘皮色素超声波辅助提取工艺) [PDF]
Shipin kexue jishu xuebao, 2014 Pigment was extracted from citrus peels with the method of ultrasonic extraction. The single-factor experiments were applied to investigate the effects of the particle size, solid-liquid ratio, ultrasonic output power, ultrasonic extraction time, and ...
DENG Tao(邓 涛) +2 more
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Development of New Ultrasonic Flow Meter [PDF]
, 2015 过去，机械流量计和电磁流量计占据了国内流量计市场的绝大多数份额。但是，二者都存在着致命的缺陷，比如寿命短、流体质量要求高等，这些缺陷阻碍了流量计性能的进一步提升。近些年，超声波流量计在流量测量仪器领域所发挥的作用越发重要。相比于其它流量计，超声波流量计维护方便、寿命长等特点使其更能满足市场需求。最重要的是，它更容易获得高精度的测量结果。 随着超声波流量计在工业和商业领域得到越来越广泛的应用，也就越来越迫切地需要提高其测量性能。为了改进超声波流量计的测量稳定性，本文设计了一种圆管和方管相结合的新型流量管 ...
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