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101.
水环境的恶化,使水工钢闸门腐蚀加重,传统的防腐工艺保护效果下降。聚酯玻璃钢复合防腐层的水工钢闸门防腐工艺具有使用设备少,工艺简单、防腐效果好、成本低等优点,适用于在各种水环境中作各种形式的水工钢闸门防腐,效果良好。该文结合江苏省淮海农场工程施工经验,提出了水工钢闸门聚酯玻璃钢复合防腐层结构设计、施工工艺及质量标难,为今后的推广应用提供了一定的参考依据。 相似文献
102.
103.
Donghua Zhang 《应用聚合物科学杂志》2006,101(6):4372-4377
Polyaniline (PANI) was synthesized by chemical oxidative polymerization of aniline (ANI) in the presence of alumina (Al2O3) particles. The polymerization of ANI occurred preferentially on the surfaces of the particles, resulting core–shell structured alumina–polyaniline (Al2O3‐PANI) particles. Morphology examination showed that with decreasing of the weight ratio of Al2O3/ANI in the reactants, the thickness of the PANI layer increased and changed from an even surface morphology to a particulate morphology. UV–vis and Fourier transformed infrared (FTIR) spectra indicated that there is no chemical interaction between the PANI layer and the Al2O3 surfaces. The PANI layer adhered well to the particles and can be used as anticorrosive fillers for polymer coatings. Enhanced corrosion protection performance was achieved for the emeraldine base (EB) form of PANI deposited Al2O3 particles (Al2O3‐EB) filled epoxy coating on carbon steel in 3.0 wt % aqueous NaCl solution. The particles demonstrate both excellent corrosion protection performance and lower cost, which will be of great importance in practical applications. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 4372–4377, 2006 相似文献
104.
Yang Lüyun 《中国稀土学报(英文版)》2006,24(Z2)
The fabrication of one kind of large core area Nd3 doped silicate glass photonic crystal fiber, and demonstration of the fiber's waveguidence properties were reported. This fiber owns a random air hole distribution in the cladding. The measured minimum loss of this kind of fiber is 10 dB·m-1 at 660 nm. These fibers can sustain only a single mode at least over wavelength ranging from 660 nm to 980 nm. 相似文献
105.
Hemanshu Bhatt Kimberly Y. Donaldson D. P. H. Hasselman Kenneth Chyung Mark P. Taylor 《Journal of the American Ceramic Society》1991,74(6):1463-1465
A study concerning the effect of fiber orientation on the thermal conductivity of a uniaxial carbon-fiber-reinforced borosilicate glass was conducted. For thin specimens, and thick specimens with specimen sides cut parallel to the fiber direction, the dependence of thermal conductivity on fiber orientation showed excellent agreement with theoretical behavior predicted for a composite infinite in extent. In contrast, the thermal conductivity data for rectangular thick specimens fell well below the data for the thin and angled specimens. For fiber orientation of 45° and higher, at which the heat was directed toward the side of the specimen rather than across, the thermal conductivity values showed excellent agreement with theoretical behavior predicted for a finite composite strip with insulated sides. 相似文献
106.
用差热、热重法对原丝的热性能及由不同预处理方法所引起的PVA纤维的热行为变化进行了研究;并通过模拟脱水条件,用不同升温速率,求出了经不同预处理纤维的脱水反应活化能。结果表明,PVA原丝在230℃有一软化点,三种预处理都不同程度地影响了原丝的热效应变化;纤维在180~340℃主要为脱水反应;原丝及经脱水剂、O_3和O_3综合脱水剂处理的纤维,其脱水反应的表观活化能分别为:164.3kJ/mol,92.9kJ/mol,130.5kJ/mol和117.6kJ/mol。 相似文献
107.
介绍了Delta4型压力筛生产全漂白硫酸盐法马尾松浆的运行情况,对存在的问题进行分析探讨,并对比了技改重新选型后的生产情况。 相似文献
108.
Jun Rong Li Jun Wang Jia Rui Xu Ming Qiu Zhang Min Zhi Rong Qiang Zheng 《Composites Science and Technology》2006,66(16):3126-3131
The authors of this paper synthesized a series of amphiphilic triblock copolymers of polystyrene-b-poly(ethylene glycol)-b-polystyrene (PS-PEG-PS) having different PEG/PS ratios with nearly identical molecular weights of the entire copolymers. The interfacial interactions in the composites consisting of carbon black and the copolymers can thus be tailored. When these conducting composites are exposed to certain solvent vapors, their electrical resistances greatly increase, showing the gas sensitivity. The present work indicated that this switching behavior is controlled by the structural relaxation of the composites because matrix swelling acts as the main mechanism. The response time has been correlated with absolute temperature by Arrhenius equation, and the estimated activation energy reflects mobility of the fillers involved in the solvent induced expansion of the surrounding polymer. Therefore, by using the gas sensibility of the conductive composites, the structure evolution of the composite materials in solid state and the effect of filler/matrix interfacial interaction on the relaxation property of the matrix polymer has been inspected. It was found that lower activation energy represents stronger interfacial interaction in case good solvent of the matrix was used for the test. 相似文献
109.
Jiang-Li Chen Zhuo Xu Shao-Bo Qu Xiao-Yong Wei Xiao-Hui Liu 《Ceramics International》2008,34(4):803-807
The NiFe2O4 and Pb(Zr0.52Ti0.48)O3 ceramic composites are prepared by conventional solid state reaction method. The microstructural and morphological properties of the composites are studied by X-ray diffraction analysis and scanning electron microscopy. Results indicate that the ferrite and piezoelectric phases can co-exist in the composites. The relationship between the dielectric constant and frequency (40 Hz–40 MHz) as well as temperature is also investigated. It is noted that the transition temperature of the composites is about 380 °C. A double electric hysteresis loop is observed in our composites. The magnetic properties are relatively weak according to the magnetic hysteresis loop. With increase in the content of the ferrite phase, the permeability increases. The electromagnetic properties of the as-prepared composites are tunable according to the content of the NiFe2O4 phase. 相似文献
110.