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Absract:After analyzed and tested the composition, microstructure and the mechanical property for the forging timber of the titanium alloy Ti-Al-V, Processed it into lash test samples , and made the samples having different hydrgen-content by the way of artificial hydrogen-absorption. Next, measured the impact strength vaules(ak ) of the titanium alloy in different hydrogen-content, and drawn the relation curve between the impact strength and the hydrogen-content. Afertwards,four samples and themselves impact fractographies whose hydrogen-contents are 48ppm,137ppm, 361ppm and 666ppm have been used for phases and the sweep electorn microscopes,Known microstructures and shapes of the hydrogenate of the different hydrogen-content tianium alloy and that the hydrogenate is sheet and its distribution in the titanium alloy. 相似文献
84.
The chaotic sequences generated by logistic map are used as the carrier, and the image secure communication scheme is proposed based on that the sequences possess a good correlation property. Promising results are obtained on Lenna image by computer simulation. The obtained results indicate that the transmitted source image can be correctly recovered and the proposed scheme is reliable when transmitter and receiver using identical initial value even under the situations of a noisy channel. However, the tiny difference of initial value between transmitter and receiver will result in failure to communication. Finally, the quality of recovered source image is assessed, and the approximate formula of bit-error rate in term of code length is also obtained. 相似文献
85.
Master towns of Chongqing includes Wanzhou, Fuling, Jiangjin, Huochuan and Yongchuan. According to the stratage of developing Western China and urbanization, this article discusses tendency of sustainable development in towns of Chongqing. Applying `evaluation method of arrangement model' and `analyze method of equal difference ', the authors find the short wming of the quality of urbanization and the sustainable development in five towns. So the article takes center city and towns construction and set up cooperation mechanism between the five cities that will be sure to increase momentum and ability of Chongqing for Sustainable development object. 相似文献
86.
A two dimension opto electronic test method has been developed to determine the distribution characteristics of cancellous bone porosity. The fresh pig tibiae concellous bone in behind leg was sectioned. A total of 36 cancellous bone sections were divided two groups. The first group consisted of 18 transversal sections along the axial direction, and the second group consisted of 18 axial sections along the transversal direction of the tibiae. Their images were examined microscopically and processed quantitatively. The total area, solid matrix area and pore area of each specimen and its porosity were determined, too. The cancellous bone porosity is gradually decreased along the axial direction of tibiae and approaching to the compact bone, but almost constant along the transversal direction. Cancellous bone is modeled as a transversely isotropic, liquid saturated porous solid. The two dimension opto electronic test method can be used to relatively accurately determine the distribution characteristics of the cancellous bone porosity from different directions if the cancellous bone sections are enough. 相似文献
87.
Visual Electroencephalograph (VEEG) is a new type of digital, information electroencephalograph. As an important part of Visual Electroencephalograph, Health Record Management System(HRMS)is integrant to store electroencephalographic data plentifully, show and edit their waveforms, analyze the data on line or off line. By the most popular and steady Relational-Database technology, ADO Application Programming Interface (API) and Visual C++ programming tool, the system has the friendly interactive interface and the functions of adding, updating, deleting, recalling, counting health record information, etc. Integrated with other parts of VEEG, HRMS ameliorates traditional EEG and overcomes some disadvantages of it such as discommodious to record, difficult to read and hard to get useful information. This paper introduces main functions, structure design and components of Health Record Management System. 相似文献
88.
为探索有效的杀灭蜱方法,减少蜱虫危害,选择新疆阿勒泰地区青河县查干郭勒乡蜱虫流行较严重的一家农户,开展了杀虫油剂和伊维菌素联合应用防控家畜蜱虫试验。试验分为杀虫油剂组、伊维菌素注射液组、杀虫油剂和伊维菌素注射液联合使用组和不用药的对照组。每组有50只不同年龄的牛、羊、马等家畜,其饲养管理、放牧条件、圈室条件都基本相同。杀虫油剂组、伊维菌素注射液组间隔1个月,同法同量进行2次用药;杀虫油剂和伊维菌素注射液联合使用组先使用杀虫油剂,1个月后注射伊维菌素注射液。用药后观察无蜱的维持时间和第1次用药90 d后仍发现蜱的试验动物数量,计算不同试验组的杀虫效果。结果显示,杀虫油剂组、伊维菌素注射液组、杀虫油剂和伊维菌素注射液联合使用组用药后的无蜱维持时间分别为70、60、90 d,预防效率分别为90%、86%、100%。结果表明,杀虫油剂和伊维菌素注射液联合使用,可起到最佳的蜱虫预防效果。 相似文献
89.
西伯利亚鲟隶属辐鳍亚纲(Actinopterygii)、软骨硬鳞总目(Chondrostei)、鲟形目(Acipenseriformes)、鲟科(Acipenseridae)、鲟属(Acipenser),主要分布于俄罗斯西部的鄂毕河至东部的科雷马河之间的西伯利亚各河流中,是极具经济价值的鱼类,其肉食用价值高、其皮可做成优质皮革,特别是由其卵加工成的鱼子酱在国际上享有"黑色黄金"、"黑珍珠"之称.随着我国成功引进欧洲西伯利亚鲟和孵化育苗设备,在我国取得了优于其它种类的养殖效果,成为近年鲟鱼养殖的重要种类之一.然而随着养殖规模不断扩大,养殖环境也发生了巨大变化,高密度养殖使养殖水体恶化,病害频发,症状多样,病因复杂,病原种类多,已成为制约西伯利亚鲟健康养殖的重要因素之一. 相似文献
90.
近年来,我国羊毛产量及质量均有所提升,但是因外毛纺织品逐渐向着高档、柔软、轻薄的方向发展,人们对羊毛品质提出了更高要求.本文就细毛羊改良及饲养管理技术介绍如下,以期为提高我国细毛羊产量及质量提供参考.
1 杂交改良
1.1 种公羊选择
细毛羊种公羊需体质结实,同时被毛品质良好.通常在剪毛前1个月挑选,标准公羊需满足以下要求:第一,头型整齐、鼻梁挺直、背部宽直、精神振奋、双眼明亮;第二,头毛长势良好,可延伸至双眼连线位置;第三,颈部褶皱明显;第四,体型匀称、四肢结实;第五,羊毛密度佳、无浮毛;第六,腹毛长势良好;第七,睾丸发育良好. 相似文献