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991.
Colors from naturally dyed fabrics recently have attracted both consumers and manufacturers in fashion markets. Even though color attributes of the fabrics have been partially observed in some literature, a data base of colors for natural colorants in fabrics needs to be established and the colors to be characterized according to systematic color notations and tones in order to relate the traditional natural colors to contemporary color communication systems. Therefore, a study was performed to investigate color characteristics for a given large set of natural colorants‐dyed fabrics based on the Munsell color notations, to analyze their tones with relation to the notation such as hue, value, and chroma, and finally to identify the effects of mordanting, an important coloring auxiliary, on the colorimetric properties of the fabrics. As a result, the dominant hue for a total of 350 naturally dyed fabrics was yellowish families followed by reddish and purplish ones in the Munsell notation owing to the use of leaves and plant as usual natural dyestuff, which confirms the limit of color hues of the fabrics. Color value for most of naturally dyed fabrics was generally higher whereas the chroma was lower, which means that most of colors for naturally dyed fabrics tended to be bright and weak shaded. Grayish, light grayish, and soft tones were the main tones of natural colorant‐dyed fabrics. All of hue, value, and chroma were found as being influenced by mordanting in that more particularly; iron mordanting was likely to cause the decrease of both value and chroma for most of naturally dyed fabrics. These results could provide a systematic color data for naturally dyed fashion fabrics and suggest a future direction of color development for them. © 2008 Wiley Periodicals, Inc. Col Res Appl, 33, 148–157, 2008 相似文献
992.
BACKGROUND: A slight change of polymer structure leads to a significantly different solubility parameter (SP), which is related to incompatibility and interface anchoring energy between a polymer and a liquid crystal (LC). RESULTS: Holographic gratings in polymer‐dispersed liquid crystals have been fabricated based on various urethane acrylate oligomer sizes and type of reactive diluent at two LC loadings. A large SP gap, using N‐vinylpyrrolidone as reactive diluent, gave much faster saturation of diffraction efficiency at higher level, but the grating failed to operate. On the contrary, films having a small SP gap, using 2‐ethylhexyl acrylate, operated under 20 V with a response time of about 10 ms, although their saturation of diffraction efficiency was relatively low. The results were interpreted in terms of morphology (determined using scanning electron microscopy), anchoring energy and resin elasticity. CONCLUSION: Low driving voltage and high diffraction efficiency are obtained by controlling the SP gap between LC and polymer. Copyright © 2007 Society of Chemical Industry 相似文献
993.
我国沥青混凝土心墙摊铺机开发及工程应用 总被引:1,自引:0,他引:1
沥青混凝土心墙摊捕机是沥青混凝土心墙施工的关键设备。我国对沥青混凝土心墙摊捕机的研制做了大量的工作,其中联合式心墙摊捕机已完成设计,牵引式心墙摊捕机已成功用于洞塘和坎尔其水库沥青混凝土心墙的施工,检测结果表明,其施工质量良好。该机的成功应用为联合式心墙摊捕机的制造奠定了基础。 相似文献
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995.
针对射频识别(RFID)二进制搜索防碰撞算法搜索次数多、通信数据量大等问题,在后退式搜索树算法和时隙算法的基础上,提出一种新的计数型双时隙RFID防碰撞算法CBS。CBS算法根据标签中的时隙计数器和阅读器收到的碰撞位信息对标签进行逐级分类搜索,并将应答标签分为两组,分别在两个时隙向阅读器返回数据信息;且阅读器仅发送最高碰撞位位置信息,而标签仅返回最高碰撞位以后的数据位。理论分析和仿真结果表明:和传统的后退式二进制搜索(RBS)算法相比,CBS算法搜索次数减少了51%以上,数据通信量减少了65%以上。CBS算法性能优于其他常用防碰撞算法,能大幅度减少搜索次数和数据通信量,提高搜索效率。 相似文献
996.
在实际生产中,经常需要408 UL仪器与KZ-28可控震源ADVⅢ箱体配合施工,但由于这两种设备不兼容,导致了408 UL仪器记录系统产生的单炮文件号与KZ-28震源ADVⅢ箱体系统产生的该炮记录相应的振动编号匹配不上,影响了对单炮记录激发因素指标的分析,不利于后期施工方案的设计。本文介绍的软件可以准确地把单炮记录的文件号、炮点桩号等数据与震源激发产生该记录相应的振动编号、坐标等数据对应起来,最后生成Ex-cel表。该软件具有操作简单、实用性强、结果准确、便于统计等特点,文中主要对该软件的设计思路和编程原理进行了介绍。 相似文献
997.
998.
目前,炼钢厂对炼钢转炉的传动机构--耳轴轴承的监测手段比较落后,定期更换耳轴轴承的方式也有不少弊端;虚拟仪器(Virtual Instruments)是计算机系统与仪器系统技术相结合的产物,最常用的开发平台为美国国家仪器公司(Natinal Instruments)的LabVIEW;开发了一套基于LabVIEW 7.1的炼钢转炉传动机构在线监测与故障诊断系统,该监测系统能够获取和记录耳轴轴承振动信号和轴心位移信号,在时域和频域进行全面分析,具有显示、报警、诊断分析和历史数据查询等功能;系统已在某钢厂投入试运行,效果良好. 相似文献
999.
1000.
Xiao-Hua Che Wen-Xiao Qiao Xiao-Dong Ju Jun-Qiang Lu Jin-Ping Wu Ming Cai 《石油科学(英文版)》2016,13(1):52-63
Better well logging techniques for geologic investigations are urgently needed to identify and evaluate complex reservoirs.We describe a new type of 3D transmitter station with corresponding circuits and bodies.They can be used in a promising new technique of acoustic reflection well logging,that features better azimuthal detection capabilities,as well as better investigation depth.The transmitter stations consist of three-level subarrays that can radiate acoustic energy in any required azimuth of 3D space by circularly exciting various combinations at different levels.We tested the 3D acoustic transmitter stations and obtained laboratory directivity measurements with the3 D acoustic transmitter stations for the first time.The results show that the 3-d B beam width in the horizontal plane ranges from 59° to 67° as a result of phase-delayed excitation.The main beam is steered in the vertical plane at a deflection angle that ranges from 0° to 16° when the delay time of the excitation pulse between each pair of adjacent arc arrays is gradually adjusted.The 3-d B beam width is equal to 11°,whereas the deflection angle in the vertical plane is equal to 14°.Each of the four third-level subarrays in the same circumferential direction display consistent horizontal and vertical directivities,thus satisfying the requirements of azimuthal acoustic reflection logging. 相似文献