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YMNU—8型saw固定延迟线的研制

压电与声光 1990年第2期12卷 1-5页

作者：张晖程国辉四川压电与声光技术研究所

YMNU—8型saw固定延迟线为中心频率60MHz,延迟时间50μs的折叠式延迟线.它利用通道变换器将延时通道折叠,实现了在有限尺寸的基片上制作长延迟线.本文详细的介绍了YMNU—8型saw固定延迟线的结构设计与原理,以及参数计算和器件性能等.

关键词：固态延时线 saw YMNU-8型

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255位saw匹配滤波器

压电与声光 1989年第4期11卷 1-7页

作者：廖代材四川压电与声光技术研究所

saw抽头延迟线匹配滤波器是现代战术扩频系统关键的信号处理器件,已广泛地应用于先进的扩频通信系统,本文介绍255位saw石英抽头延迟线双相编码匹配滤波器的工作原理,设计方法和实验结果。匹配滤波器的中心频率为65.2MHz,编码速率为8.2Mb... 详细信息

saw抽头延迟线匹配滤波器是现代战术扩频系统关键的信号处理器件,已广泛地应用于先进的扩频通信系统,本文介绍255位saw石英抽头延迟线双相编码匹配滤波器的工作原理,设计方法和实验结果。匹配滤波器的中心频率为65.2MHz,编码速率为8.2Mbit/s(抽头间隔约0.123/μs),持续时间为31.25/μs,自相关峰值与最大旁瓣比为20dB。测试结果表明,采用适宜的设计方法和工艺技术可获得预期的性能。255位saw匹配滤波器的研究成功将对我国某些先进的电子系统产生深远的影响。

关键词：滤波器声表面波匹配 saw 255位

Definition of Increasing the Fibre Capturing Surface of saw Teeth of Cotton Ginning Machine through Mathematic Modelling

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World Journal of Mechanics 2011年第3期1卷 122-126页

作者： Azizov Shuhrat Mamatovich Karimov Abdusamat 不详

Theoretical and the experimental researches executed in Uzbekistan and abroad explored some ways of a substantiation of a rational profile of a tooth of a saw and its fibre capturing ability. Despite that, untill now, optimum parameters of a saw gin which provides high quality ginning without harming the quality of cotton fibre have not been found. Considering the stated above in the given job the influence of the changed form of saw teeth on fibre-capturing area is examined. The analytical formulas for the additional area promoting to double the fibre capture quantity by saw teeth are received.

关键词： Factor of Proportionality Radius of a saw Fibre Gin Teeth Linear Speed New Profile

Influence on the propagation velocity of saw by a force applied on surface

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Chinese Journal of Acoustics 2009年第4期28卷 322-331页

作者： ZHENG Min WEN Yumei LI Ping College of Opto-electronic Engineering The Key Laboratory for Opto-electronic Technology & SystemsMinistry of Education Chongqing University Chongqing 400030

When a force is directly applied to the propagation surface of surface acoustic wave （saw）, the velocity of saw is varied. Then the loading force can be introduced by effective material coefficients and the velocity of saw is calculated via the general Green＇s Function. The experimental results accord with the above numerical calculation very well. It also shows that the propagation loss will increase with the force load, and the velocity variation of saw is proportional to the force loaded to the surfaces of saw resonators, which has a high sensitivity about 5.97 m/s·N.

关键词： saw

Performance analysis of the saw joint of duplex stainless steel clad plate

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Baosteel Technical Research 2018年第3期12卷 25-30页

作者： QIAN Weifang Research Institute Baoshan Iron & Steel Co.Ltd.

Duplex stainless steel clad plate exhibits good performance and is relatively inexpensive,however,some difficulties must be overcome when welding different materials. In this study,submerged arc welding（ saw） was used to weld Baosteel ship clad plates（ 2205 ＋ DH36）,and the performance of the welded joints was tested. The results indicate that the mechanical properties and the corrosion resistance of the welded joints meet the required specifications. The distribution of the main anti-corrosive elements and the phase ratio of the welded joint are analyzed,thereby indicating excellent uniformity and confirming that the welded joint is corrosion resistant.

关键词： duplex stainless steel clad plate saw welded joint corrosion resistance

saw Palmetto-Based Nutritional Supplement Prostataplex Relieves Symptoms of Benign Prostatic Hyperplasia (BPH) in Patients with Mild to Moderate BPH

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Open Journal of Urology 2012年第3期2卷 104-108页

作者： Qingwen Xie Jing Leng Jianwei Lv Allan Pantuck Lawrence Yen Mina Shariff Kenneth Kami Jianyu Rao Rong Shi Department of Pathology and Laboratory Medicine David Geffen School of Medicine University of California Los Angeles USA Department of Preventive Medicine School of Public Health Shanghai Jiao Tong University School of Medicine Shanghai China Department of Research DRM Resources Costa Mesa USA Department of Urology David Geffen School of Medicine University of California Los Angeles USA Department of Urology Shanghai Renji Hospital Shanghai Jiao Tong University School of Medicine Shanghai China

The goal of this study was to assess the efficacy of the saw palmetto-based nutritional supplement, Prostataplex, for relieving the symptoms associated with benign prostatic hyperplasia (BPH) in men with mild to moderate degrees of BPH. A randomized, double-blind, placebo-controlled trial was performed in Shanghai, China. Eighty patients with BPH were randomly assigned to either the intervention group (39 cases) or control group (41 cases). Patients in the intervention group were administered Prostataplex orally and placebos were given to patients in the control group. The duration of treatment was 12 weeks in both groups. Following the intervention of Prostataplex, the maximum urinary flow rates (MFR), total scores of International Prostate Symptom Score (IPSS) and quality of life indicators were significantly better among the patients in the intervention group than those in the control group (P < 0.01 for all variables). Significant improvement of symptoms including dysuria, reducing nocturnal polyuria and increasing urinary flow rate was seen after two months of intervention, especially for the improvement of incomplete bladder emptying. Prostataplex has positive effects on improving symptoms as well as quality of life in men with mild to moderate BPH.

关键词： saw Palmetto Prostataplex Benign Prostatic Hyperplasia Intervention

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IDT镜象连接式saw低插损滤波器

压电与声光 1990年第3期12卷 1-4页

作者：钟宁武以立四川大学无线电系

本文以saw叉指换能器的等效电路模型作为物理模型,分析研究了镜象连接式的两种典型结构,介绍了基本镜象连接单元的形成原因和它的各种用途.实验结果表明,基本镜象连接单元的插损为6.2dB,十换能器结构滤波器的插损为4.0dB.

关键词： saw 滤波器镜象连接 IDT

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用saw延迟线振荡器探测微量化学气体

压电与声光 1989年第2期11卷 52-58页

作者： H.Wohltjen 姚学良美.电子与电气工程师协会

证明了saw延迟线振荡器的谐振频率对淀积在延迟线表面上的有机薄膜很敏感。理论指出saw器件对质量负载的灵敏度取决于谐振频率的平方。用谐振频率为31,51和112MHz涂有严格控制成分及厚度的有机膜的器件对这个关系进行了实验研究。若器... 详细信息

证明了saw延迟线振荡器的谐振频率对淀积在延迟线表面上的有机薄膜很敏感。理论指出saw器件对质量负载的灵敏度取决于谐振频率的平方。用谐振频率为31,51和112MHz涂有严格控制成分及厚度的有机膜的器件对这个关系进行了实验研究。若器件用上合适的吸附性涂层,可将saw振荡器的质量灵敏度用于制造非常灵敏的化学传感器。从工作频率为290MHz的saw延迟线振荡器(是迄今所报道过的最高频率的saw化学传感器)得到的结果表明,要对浓度大体低于1×10^(-4)(以体积计)的有机气体进行快速探测是容易办到的。

关键词： saw 延迟线振荡器探测气体

改进低损耗saw滤波器用换能器的几种新结构

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压电与声光 1990年第1期12卷 1-10页

作者：刘一声四川压电与声光技术研究所

最近,报道了多种改进低损耗saw滤波器用换能器的新结构.改进的换能器包括单相单向换能器(SPUDT)、群型单向换能器(GTUDT)、群型单相单向换能器,(GSPUDT)、新型单相单向换能器(MEMUDT、SUDT、RSUDT)以及低损耗saw-TV-IF滤波器用的故意不... 详细信息

最近,报道了多种改进低损耗saw滤波器用换能器的新结构.改进的换能器包括单相单向换能器(SPUDT)、群型单向换能器(GTUDT)、群型单相单向换能器,(GSPUDT)、新型单相单向换能器(MEMUDT、SUDT、RSUDT)以及低损耗saw-TV-IF滤波器用的故意不完全的(intentionally inperfeet)单向换能器(HUT)等.本文叙述上述各种换能器结构的工作原理和结构设计.并介绍了几种实验性的低损耗saw滤波器的主要性能.

关键词： saw 滤波器换能器低损耕结构