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1.
In order to protect the system of fiber Bragg grating (FBG) and keep its sensing performance on a high score, an adhesive-free bond which is considered as the alternative for epoxy adhesive technology is demanded. An electroless Ni-P plating process without coarsing for fiber Bragg grating was presented. With this plating method, the FBG was coated with a metal clad of Ni-P. By Scanning Electron Microscope (SEM), Energy Dispersive Spectrometer (EDS), X-ray diffraction (XRD) and Temperature vibration tests, the composition, structure and adhesion force of the plating coatings were analyzed. And the results indicate that the coating is smooth, flat and compact. The solder ability of Ni-P clad was tested by welding the FBG into metal components, and the results reveal that the coating films can meet the requirements of an adhesive-free bond.  相似文献   

2.
For the transmission pressure 27.5 kV of the railroad AC contact network, and the non parallel (on earth) arbitrary plane for the wire wearing surface, the optic fiber was used to isolate the high voltage and to transmit the measurement signal. A remote grating type adaptive automatic machinery transducer was used to detect the AC contact network wire wearing surface with about seven meters from the ground. Based on this method, a system was designed and calibrated, achieving measurement of wire rubbing with high voltage. The actual measurements indicate that the method and the system satisfy the demand of the measurement of contact network wire wearing. The method is significant to the geometric sense measurement of the high voltage charged body.  相似文献   

3.
Based on the principle of double frequency laser interference measurement ofhigh accuracy linear grating. This technique is discussed in detail from two aspots:totol lenth cumu-lative error measurement and Morie fringe signal quality analysis of linear grating.It includes lasersignal processing tochnique, signal sampling,computer interface circuit and related algorithm. withthis methed, we can not only get its accuracy parameter of a linear grating, but aiso analyze the er-ror factors which would affect the accuracy of a linear grating in graving process. In addition,it cancny out dynamic measuremtns for other length metrological elements.  相似文献   

4.
The relationship between grating parameters and wavelet spectrum values was deduced. Firstly, the vector diffraction theory and scalar quantity diffraction theory were used to calculate the diffraction efficiency. The approximately equal conditions were analyzed next. Finally, the relationship was obtained. The gap width of the plane transmission grating was calculated with the Mexico hat wavelet. The relationship among the parameters of the plane transmission grating, diffraction efficiency and Mexico hat wavelet values was obtained.  相似文献   

5.
Since D. Post promoted the holographic moire' interferometric techniques. It has been developed in all kinds of aspects. It is applied in measuring mechanical parameters in the fields of fracture mechanics, composite material mechanics, biomcchanics etc. Howerver, some problems in the development of the holographic grating and holographic moire' techniques theory are still existed. This paper deducted the frequency of holographic grating and the equation of moire/ method's displacement with Fourier opticsal, and improved the holographic moire' technologic theory. It provides a theoretic foundation for extensive applying of the holographic moire' techniques.  相似文献   

6.
A new grating tiling device with 2×2 gratings is developed to obtain a large aperture grating. For the stability of the device impacted by the HVAC vibration, a dynamic finite element analysis model is established. The random vibration response of the model under the measured power spectral density as stimulus has been carried out by the ANSYS software, and the data has been compared to the experimental data. The results show that the device can meet the stability requirements in the work environment.  相似文献   

7.
棉花纤维发育的分子机理及品质改良研究进展   总被引:9,自引:3,他引:6  
 棉花纤维细胞的分化与发育是一个复杂有序的过程,在不同的发育时期均有大量的基因表达,参与纤维细胞发育的调控。转录因子和植物激素在棉纤维细胞分化起始过程中起重要的作用。纤维细胞壁结构、细胞骨架和糖类、脂类代谢相关的基因以及激素信号分子与纤维细胞的伸长密切相关。棉纤维次生壁合成时期主要是纤维素的合成及沉积过程,蔗糖合成酶和纤维素合成酶等基因在这一时期起关键的调节作用。在棉纤维发育分子生物学研究的基础上,利用基因工程改良棉花纤维品质也取得了一些研究进展。  相似文献   

8.
棉纤维发育突变体是克隆棉纤维发育关键基因和阐明其发育分子机理的优异资源。陆地棉李氏超短纤维突变体(Li1li1)是显性单基因突变体,表现为显性纯合体(Li1Li1)致死,显性杂合时(Li1li1)表型为茎秆扭曲、叶片卷曲和纤维短至6 mm,而隐性纯合体(li1li1)则表现为株型和纤维发育都正常。本文对开花后10 d的李氏纤维发育正常材料(li1li1)和超短纤维突变体(Li1li1)胚珠纤维混合体进行mRNA差异显示反转录PCR(DDRT-PCR)分析,获得2条在李氏纤维发育正常材料中上调表达的差异片段。测序及DNA序列的生物信息学分析表明该差异片段分别与编码谷氨酸脱羧酶和质子焦磷酸酶的基因有较高同源性。通过电子拼接,5¢RACE和全长cDNA序列验证,克隆了棉花的谷氨酸脱羧酶(GhGAD)和质子焦磷酸酶(GhVP1)基因全长cDNA, 进一步对其功能和染色体定位进行了初步分析。转录水平分析表明,这两个基因在棉花根、茎、叶和纤维中组成性表达,在棉纤维中优势表达。利用本实验室陆地棉遗传标准系TM-1和海岛棉海7124培育的含140个单株的BC1作图群体,将GhGAD和 GhVP1分别定位在第12条染色体和第8条染色体。  相似文献   

9.
苹果肉渣膳食纤维丰富,加入蛋糕中能明显提高其中的膳食纤维含量。将苹果肉渣膳食纤维粉分别以0%,5%,10%,15%的量加入面粉而混合制得苹果肉渣膳食纤维蛋糕,通过测定其比容、保水性、质构等指标,分析影响其品质的主要因素,确定苹果肉渣膳食纤维的最适添加量。结果表明,随着苹果肉渣膳食纤维粉添加量的增加,蛋糕物理性质变化不大,其中当苹果肉渣膳食纤维粉添加量为5%时,蛋糕品质最好。  相似文献   

10.
棉花纤维品质分子育种的现状及展望   总被引:18,自引:4,他引:14  
张天真 《棉花学报》2000,12(6):321-326
棉纤维是重要的纺织工业原料。随着人民群众对衣着要求的普遍提高,纺工部门引入高效快速的纺纱技术,对棉花品种的总体纤维品质,提出了更高的要求。目前国内外棉花育种家除了利用常规技术外,还大规模开展了棉纤维品质改良的分子育种研究。本文综述了国内外利用克隆出的棉纤维发育基因以及外源基因开展棉纤维品质改良的转基因育种和棉纤维优质基因的分子标记筛选和辅助选择育种的研究进展。同时,根据我国目前棉花品种品质水平、生产状况,提出了棉花品质育种策略。  相似文献   

11.
Cotton is one of the most important economic crops in the world,and it provides natural fiber for the textile industry.With the advancement of the textile technology and increased consumption demands on cotton fiber,both cotton yield and quality should be enhanced.However,cotton yield and fiber quality are complex quantitative traits and are usually negatively associated that hampers the simultaneous improvement of lint yield and fiber quality by traditional breeding.  相似文献   

12.
The shear tests were conducted on 18 different groups of deep beams with steel fiber and polypropylene fiber and two groups high performance concrete deep beams without fiber according to the orthogonal experimental design. By a definition of shear ductility index shear ductility of deep beams was analyzed quantitatively. The influence of six factors on improving shear ductility of deep beams was compared by direct-viewing analysis of the orthogonal experiment. The contributory factors such as the species of steel fiber, the volume fraction of steel fiber, the length/diameter aspect ratio of steel fiber, the volume fraction of polypropylene fiber, the ratio of web horizontal reinforcement and the ratio of web vertical reinforcement were analyzed. Results show that the volume fraction of steel fiber plays the most important role in improving shear ductility of deep beams exceeding the ratio of web horizontal reinforcement and the ratio of web vertical reinforcement, whereas species of steel fiber has minimum effect. Hybrid fiber can be used to greatly increase shear ductility of deep beams and shear ductility is at the most increased by 40.7% although it can not change the brittleness of shear damage. The full-range shear behaviors of deep beams through ABAQUS are analyzed and the calculated results are in good agreement with test results.  相似文献   

13.
棉花4个栽培种纤维初始发育的比较研究   总被引:3,自引:1,他引:2  
李成奇  郭旺珍  张天真 《作物学报》2007,33(8):1346-1351
利用扫描电镜技术,对棉花4个栽培种陆地棉(泗棉3号)、海岛棉(海7124)、亚洲棉(定远小花)以及非洲棉(A1-50)开花前后的胚珠进行比较观察,并探讨延迟授粉对各棉种纤维初始发育的影响。结果表明,在南京大田气候条件下,除亚洲棉外其他3个棉种均在开花前1 d出现纤维细胞突起。在开花当天和开花后1 d,所有棉种的纤维突起(或伸长)密度均在珠柄顶部的脊突处最大,合点端和胚珠中部其次,珠孔附近最小。除陆地棉外,其他棉种在开花后1 d的纤维伸长密度均低于开花当天的纤维突起密度。说明随着棉胚珠体积的膨大,其他3个棉种胚珠表面的纤维细胞“稀释”程度大于陆地棉。在棉纤维初始发育阶段,纤维密度不仅受气象因子如温度的影响,而且与授粉时柱头的生活力密切相关;延迟授粉对纤维初始发育的影响以非洲棉较大,海岛棉较小,亚洲棉和陆地棉最小。本研究为理解棉纤维的分化和发育机理, 探讨4个栽培棉种纤维发育的亲缘关系,及人工授粉棉纤维的杂种优势利用提供了一定的理论依据。  相似文献   

14.
为了研究亚麻纤维作为可再生增强复合材料在生产中的应用,笔者综述了近年来亚麻纤维的组成结构与机械性能及亚麻纤维在增强复合材料中的应用,并介绍了目前亚麻纤维复合材料的生产工艺。发现新型界面相容剂的开发对于提高亚麻纤维增强复合材料的高耐久性具有重要作用,探讨了亚麻纤维增强复合材料的应用前景和发展趋势,以及生物复合材料开发的可行性。  相似文献   

15.
选择天然棕色棉品种湘彩棉2号和绿色棉品种皖棉39,研究其纤维品质性状形成特点及激素调节作用。结果表明与常规白色陆地棉苏棉9号(对照)相比,2个彩色棉品种的纤维长度均较低,尤其皖棉39显著低于对照,主要是花后10~30 d伸长速率明显下降。两个不同彩色棉品种的纤维比强度、马克隆值和成熟度值均显著低于对照,且主要与各个品质指标形成关键期的增长率较慢有关。两个彩色棉品种10 DPA (days post anthesis)和20 DPA纤维中IAA含量,30 DPA和40 DPA ABA含量均显著低于各自对照。应用20 mg L-1 GA3处理棉铃后,湘彩棉2号、皖棉39 20 DPA纤维中IAA含量分别比各自对照提高51.07%、64.33%;吐絮时纤维长度分别比各自对照增加8.13%、13.96%;应用20 mg L-1 ABA处理棉铃,40 DPA纤维中ABA含量分别比各自对照提高38.96%、24.40%,纤维比强度、马克隆值和成熟度也显著增加,其中又以皖棉39增加幅度较大。说明天然彩色棉纤维内源激素IAA和ABA含量不足影响纤维品质性状的形成,而通过植物生长调节剂应用可调节内源激素含量,改善纤维品质,且调节效应因植物生长调节剂和品种不同而异。  相似文献   

16.
棉纤维主要品质性状的气象生态模型研究   总被引:2,自引:1,他引:1  
 通过分析1994—1995年在陕西杨陵和山东的鄄城、泰安、东营以及2001—2002年在长江流域棉花品种试验区域进行的试验资料,在不考虑土壤、栽培调控等因素的前提下,确定棉花铃期日均最低温、日均最高温和相对湿度、夜均温和日均降水量分别是影响棉纤维长度、比强度、麦克隆值的关键气象因子,并建立了基于铃期关键气象因子对棉纤维长度、比强度和麦克隆值的气象生态模型。上述模型既强调了遗传性对棉纤维品质性状的决定作用,也体现了气象生态因子的作用。棉纤维长度、比强度和麦克隆值气象生态模型RMSE分别为0.985 mm、1.003 cN·tex-1和0.233,模拟值与观测值1:1直方图吻合度好,模型具有较好的预\{测性。  相似文献   

17.
To prevent asphalt pavement from cracking under low temperatures and prolong its fatigue life, we tested the properties of a new type of steel fiber asphalt pavement. The tests evaluated Marshall stability, dynamic ruts, and cleavage strength under both low and normal temperature conditions. We also analyzed the anti-corrosion property of steel fiber and the factors affecting the properties of the steel fiber asphalt mixture. The steel fiber asphalt pavement was installed on a highway in Chongqing, P. R. China to investigate the construction art of the steel fiber asphalt mixture and examine its effect in field use. The test results and concrete use in the field show that the cleavage strength and flexibility of steel fiber asphalt concrete increase due to the action of steel fiber. We conclude that the anti-cracking capacity of asphalt pavement under low temperature conditions can be improved by steel fiber. The construction art of steel fiber asphalt pavement is the same as common asphalt pavement without the necessity of anti-corrosion processing for steel fiber. The research results are useful for pavement material selection in low temperature regions and heavy traffic road pavement designs.  相似文献   

18.
选择棉纤维比强度差异明显的2个品种,研究了棉纤维发育关键酶(蔗糖合成酶和β-1,3-葡聚糖酶)活性的变化特征及其与纤维比强度的关系。结果表明,棉纤维发育过程中蔗糖合酶、β-1,3-葡聚糖酶活性变化特征在生化和mRNA转录水平上均存在明显的差异,影响纤维素的沉积特性及纤维比强度。高强纤维品种(科棉1号,平均比强度为35 cN·tex-1)的蔗糖合酶和β-1,3-葡聚糖酶活性及其基因表达量和维持高表达时间均高于低强纤维品种(德夏棉1号,平均比强度为26 cN·tex-1)。其中,高强纤维品种蔗糖合酶的基因表达量铃龄25 d时明显高于低强纤维品种,而β-1,3-葡聚糖酶的基因表达量则在铃龄10~25 d高于低强纤维品种。在纤维素形成过程中,高强纤维品种的纤维素累积平缓且纤维素累积持续期长于低强纤维品种,品种间差异程度受棉株果枝部位影响。在棉纤维发育过程中,Expansin、β-1,4-葡聚糖酶的基因表达量随铃龄的增加呈下降趋势(铃龄20 d时表达量显著下降),这与棉纤维形成过程(铃龄25 d前伸长较快,随后趋于停止)一致,且高强纤维品种维持高表达时间长与其纤维伸长期较长相吻合。  相似文献   

19.
随着人们生活水平的不断提高,饮食日趋精细,缺乏膳食纤维的情况也日趋严重,膳食纤维资源的开发和应用成为研究热点。从化学构成、提取工艺、改性应用等方面综述了苹果膳食纤维,论述了提取中各工艺的特点,并介绍了不同提取方法的最佳工艺。  相似文献   

20.
Corn fiber is a concept proposed in 1948,which involves in the polymeric fiber that made from corn as the raw material, and it was turned to lactic acid, transformed into lactide, and polymerized to polylactide or polylactic acid. Since that, some progresses have been made. However, the feature of corn fiber is determined by the molecular weight of polylactide. In general, corn fiber is formed by means of the melt-textile or no-hydrous textile. The situations, technologies, properties of the corn fibers are reviewed, as well as the processing about lactide synthesis, lactide condensation polymerization. It has some professional properties, such as high transparency, well-heat-resistant stability, well-colors, and full biodegradability, as well as the feature in ecological recycle. These means the corn fibers are new-typical and green, full-environmental fibers, especially for China as the second great number of the products of corn. Research and development of corn fibers are launched off in the world. Some problems existes in the corn fiber manufactured field are to be evolved, which are small scale, high cast, little of end-products enrolled in the market. So is down the cast of corn fiber manufactured as the very important works. This means that systemic studies of the fiberous polymerization and processing are crucial and highlighted to in this field.  相似文献   

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