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101.
Temperature measurements have been performed in the process of electron‐beam curing of EB‐I and EB‐II epoxy resin systems. The influence of initiator content, resin type, and dose rate on the temperature of the systems was studied. Transverse and longitudinal temperatures of samples in the glass vessel were also analyzed. The nature of temperature curves varied with the different epoxy resin systems in the steel mold, but did not change with different contents of the initiator. At the same time, the heat had no effect on the gel fraction of epoxy resin systems. The temperature curve was greatly affected by the dose rate, and its peak value, peak width, and plateau value also increased with it. The transverse temperature of EB‐II glass vessel samples increased as the radiation dose increased and, in the same sample, the temperature reduced as the distance between the radiation center and the test point increased. The longitudinal temperature of EB‐I and EB‐II resin systems in a glass vessel decreased as the radiation depth increased. As the radiation dose increased, the temperature of the EB‐I resin system increased simultaneously, while that of the EB‐II resin system initially increased and then kept constant when the dose reached a certain value. The temperatures of these two resin systems decreased rapidly when the radiation process stopped. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2217–2222, 2004 相似文献
102.
用动态DSC研究了笼型γ-氨丙基倍半硅氧烷/环氧树脂纳米杂化复合体系的固化过程、最佳配比与热稳定性能,并用Ozawa和Kissinger—Akahira—Sunose等转化率法研究了固化反应动力学。结果表明,该体系固化峰值温度为85℃,终了温度为118℃,最佳NH2与环氧基摩尔比为0.75,热分解最高起始温度为336-356℃。Ozawa法更适合本体系的动力学分析,固化反应表观活化能为71.0765kJ/mol,反应级数为0.9855级。 相似文献
103.
研究试验温度和停放时间对胶料加工性能的影响。结果表明,试验温度对胶料的门尼粘度、门尼焦烧时间和硫化特性均有一定影响。门尼粘度测定的试验温度选择100℃;门尼焦烧时间测定的试验温度一般选120℃,SBR胶料可提高至130℃左右,以缩短试验时间;硫化特性测定的试验温度一般选185℃。试验前模腔达到规定温度后再保持15min,以使转子与模腔温度一致。胶料停放时间应控制在2h左右。 相似文献
104.
Ken Kihara Hirotaka Fujisaki Sakuichi Ohtsuka Masaru Miyao Jun Shimamura Hiroyuki Arai Yukinobu Taniguchi 《Journal of the Society for Information Display》2014,22(7):329-336
Some stereoblind observers do not perceive depth of 3D stimuli that depends on binocular disparity. These individuals, who have no disabilities, comprise over 5% of the general population. In addition, 17–30% of nonstereoblind young and young–middle people do not use disparity information in certain 3D environments, a phenomenon known as pseudo‐stereoblindness. This study aimed to investigate the relationship between aging and the proportion of pseudo‐stereoblindness in the general population. In an experiment, 134 nonstereoblind participants, ranging in age from 17 to 83 years, judged subjective depth of 3D stimuli containing binocular disparity and pictorial depth cues. Results showed that the proportion of pseudo‐stereoblindness among young (17–24 years old) and young–middle aged observers (25–39 years old) was 29%, in both cases. However, the proportion of pseudo‐stereoblind observers increased in older populations: 65% and 82% in the middle (40–54 years old) and senior (55–83 years old) age groups, respectively. These results suggest that a number of people, especially in elderly populations, have trouble perceiving depth from binocular disparity in 3D graphic contents despite their essential ability to use disparity information. 相似文献
105.
Qin Wang Qiong‐Hua Wang Jing‐Long Liang Chun‐Ling Liu 《Journal of the Society for Information Display》2014,22(10):493-498
In order to investigate visual experience for watching the autostereoscopic three‐dimensional (3D) projection display, we conduct a subjective evaluation experiment by a questionnaire when viewing video clips. Factor analysis is adopted to classify the evaluation items for the perpetual constructs of visual experience. Then a mixed design with repeated measurement analysis of variance with dimension and display duration as factors is carried out on the evaluation data to check the factorial effects and interactions for statistical significance. The results of factor analysis extract five factors including visual comfort, image quality, distortion, naturalness, and presence, which can be used as comprehensive indicators to evaluate the autostereoscopic 3D projection display. The results of analysis of variance indicate that image quality, which is used to assess two‐dimensional contents, is no longer applicable. It is necessary to give consideration to depth when evaluating 3D visual experience. Although 3D scenes enhance the overall subjective performance such as naturalness and presence, the health issues and stereoscopic distortion related to the introduction of depth cannot be ignored. 相似文献
106.
The effect of TiO2 nanoparticles for sun-weathering protection of UV-cured coatings is investigated. TiO2 is either introduced in the form of nanoparticles in the photocurable formulations or generated in situ via sol–gel process. Cured films containing comparable amounts of TiO2 were weathered for 800 h under UV irradiation and compared with free-TiO2 coating. The TiO2 presence induces a clear lower mass loss decrease during weathering as well as a lower gel content decrease. The TiO2 screen effect is also confirmed by a lower alkyl-band reduction monitored by FT-IR during weathering. The TiO2 generated in situ via sol–gel gives rise to transparent coatings without interfering with photopolymerization process and therefore without compromising UV-cured film properties. 相似文献
107.
Emulsion polymer isocyanate (
), polyvinyl acetate (
) and resorcinol-formaldehyde (
) adhesives were used to produce single lap shear specimens using resinous and non-resinous apitong (Dipterocarpus spp.) timbers. Tests showed that joints made with highly resinous apitong were about 40% weaker than similar joints made with non-resinous apitong. The resinous apitong was treated with different solvents to yield five different extractives which were characterized by infra-red analysis. Apitong extractives were then added to
and
adhesives and joints made with buna (Fagus crenata), a timber known to be low in extractives and easy to bond. Joints prepared using extractive-containing adhesives were generally weaker than those made with the unmodified adhesives. RF adhesives containing extractives cured more slowly than unmodified
. It is thought that the acidic nature of the extractives changes the pH of the system sufficiently to affect the curing mechanism 相似文献
108.
以无水三氯化铝为催化剂,用苯和1,3-口恶嗪-2-酮进行氨丙基化反应合成了二氨丙基苯。研究了物料物质的量比、反应时间、温度对反应的影响,确定了合成二氨丙基苯的较佳反应条件。通过DSC对环氧树脂中该固化剂的加入量和固化工艺条件进行了研究,对环氧树脂固化物的力学性能等指标进行了考察。 相似文献
109.
对强夯有效加固深度主要影响因素进行分析,考虑能量的转化,综合运用量纲守恒和最小二乘原理,结合一定量的湿陷性黄土地基强夯加固实例,推导了有效加固深度估算公式,并与其他公式进行比较;再结合另外两组湿陷性黄土地基实例,进一步探讨了本文公式的估算效果。新的公式反映了含水量与有效加固深度呈非线性相关,能使得计算效果更好,参数选用方便,对湿陷性黄土地基有一定参考价值。 相似文献
110.