共查询到20条相似文献,搜索用时 171 毫秒
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激光是20世纪以来人类的一项重大发明,表面清洗工艺又是工业生产中的重要环节,激光清洗技术近年来成为了国内外研究的热点问题,工业清洗工艺离不开对其机理和清洗后基材表面性能的研究,脉冲激光清洗难以定性定量描述的作用机理成为制约其应用推广的关键问题之一,主要表现在激光清洗过程中产生的光、声、热、等离子体等多场耦合作用和清洗过程中产生的复杂键合、界面破坏规律。本文中分析了在不同条件下脉冲激光清洗的作用机理,列举了国内外激光清洗的最新解决方案,并结合脉冲激光清洗的实验数据,提出了脉冲激光清洗表面性能提升的规律。 相似文献
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常压冷等离子体清洗技术在微电子工业中的应用 总被引:1,自引:0,他引:1
介绍常压射频冷等离子体清洗设备工作原理以及在微电子工业中的应用,给出用常压冷等离子体清洗设备去除光刻胶的实验结果,简单阐述该技术将对微电子工业工艺过程带来的影响。 相似文献
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溶液共混法制备聚氨酯/碳纳米管复合材料及其性能 总被引:3,自引:1,他引:2
通过强酸处理方法对碳纳米管进行改性处理并对其结构和分散稳定性进行分析。采用溶液共混法制备了聚氨
酯/碳纳米管复合材料,利用FTIR对其结构进行了分析,探讨了碳纳米管对复合材料力学性能、热稳定性能以及弹
性回复率的影响。结果表明,碳纳米管经酸处理后添加了羧酸活性基团,提高了其在溶剂中的分散性|在复合材料
中,碳纳米管以较强氢键与大分子连接,复合材料的力学性能和热稳定性能都有所提高,而弹性回复率没有受到很
大影响。 相似文献
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对PVC冲击改性剂——MBS、CPE和ACR的分子组成和分子结构进行了分析,研究了其抗冲改性机理及对PVC制品低温冲击强度、耐候性、维卡软化点、韧性的影响。从高分子热力学的角度分析了CPE和ACR在PVC中分散所形成的制品结构。指明了传统ACR和CPE在PVC改性中所存在的优缺点。在此基础上分析了理想冲击改性剂ACR应具有的结构特点,并设计和开发了新型冲击改性剂ACRHL-56和HL-58,通过试验对其性能与传统冲击改性剂ACR和CPE进行了比较,发现其性能远优于后者。 相似文献
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聚氨酯/碳纳米管复合材料的制备及其性能研究 总被引:2,自引:0,他引:2
通过强碱球磨方法对多壁碳纳米管(MWCNTs)进行了改性处理,并对其化学结构和微观形态进行了分析.采用溶液共混法制备了聚氨酯(PUR)/MWCNTs复合材料.利用扫描电子显微镜、傅立叶变换红外光谱仪对其进行了表征.探讨了MWCNTs对PUR/MWCNTs复合材料力学性能、热稳定性以及电导率的影响.结果表明,MWCNTs... 相似文献
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Lisia Lorea Valente Isabella Schönhofen Manso Eliseu Aldrighi Münchow 《Journal of Adhesion Science and Technology》2013,27(7):806-815
The aim of this study was to prepare experimental resin-based primers with varied components (silane – S, polyacrylic acid – PA, or methacrylic acid – MA) and evaluate their repair bonding ability to resin composite. Primers were prepared containing methacrylate monomers, acidic monomer, ethanol, photoinitiators and 0, 10, or 20 wt% of S, PA, or MA. Degree of C=C conversion and pH were measured. Composite blocks (Opallis, FGM) were aged by 5000 thermal cycles and composite cylinders (repairs) were built up on their surfaces. The cylinders were tested under shear stress after 24 h. Failure modes were classified under magnification. Data were statistically analyzed at α = 0.05. Primers containing MA were the most acidic compositions, whereas S-containing primers were less acidic. Incorporation of 20 wt% of the varied components decreased C=C conversion. PA-based primers had higher C=C conversion than MA-based materials. Repair bond strength results were dependent on the component added and its concentration. MA-based primers presented higher bond strength than primers containing PA. Cohesive failures within composite were predominant for S-based primers, whereas mixed failures were more prevalent for PA-based primers. In conclusion, the overall best repair abilities were observed for primers containing 10 wt% of the components tested. 相似文献
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我国微生物法水处理技术的研究进展 总被引:1,自引:0,他引:1
介绍了微生物絮凝剂的基本研究方法,综述了4种絮凝机理,对其絮凝效果的因素进行了探讨,阐述了微生物絮凝剂在众多领域的应用情况,指出了微生物絮凝剂在生产过程中的现存问题和解决措施,微生物絮凝剂具有高效、无毒,无二次污染、成本低等优点,为水处理技术的研究和发展提供了一个新的方向. 相似文献
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采用嵌入式CFPR筋和外贴碳/玄武岩纤维混杂布加固混凝土梁,设计比较了对加固材料施加预应力后的增强效果,共进行了6根梁的4点弯曲试验,并就计算结果和试验结果进行了验证,提出了设计方法.结果表明:相比于无预应力加固,施加预应力后能够进一步提升梁的开裂荷载和屈服荷载,并提高梁的服役性能.计算结果和试验结果比较吻合. 相似文献
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水稻抽穗前后施用农药情况对稻米中农药残留量的影响研究 总被引:2,自引:0,他引:2
水稻抽穗前、后施药的时期,农药种类,施药剂量与次数和稻米的安全性密切相关。供试的有机磷农药除敌敌畏未检出外,其余农药都在稻米中残留,残留量三唑磷〉乙酰甲胺磷〉甲胺磷〉毒死蜱〉吡虫啉〉敌敌畏。水稻抽穗前用药2次,甲胺磷、三唑磷均超标;用药3次,毒死蜱残留量与国家标准相当,乙酰甲胺磷未达标。上述农药剂量提高1倍,残留量提高30%~50%,用药2次除毒死蜱外,残留量均超过国家标准。水稻抽穗后用药,农药残留量明显提高,甲胺磷、乙酰甲胺磷、三唑磷、毒死蜱常规剂量用药2次,除乙酰甲胺磷未超标外,其余残留量都高于国家标准。吡虫啉抽穗前后使用,其残留量均低于食品中最高允许标准。农药残留量与糙米贮存期有关,一般贮存90d后,农药残量即低于允许残留标准。降低农药施用次数,适当降低用药量,尽量选择抽穗前用药,选用高效、安全、低残留农药,是无公害水稻生产中的重要措施。 相似文献
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Performance of Dowel-Welded L-joints for Wood Furniture 总被引:1,自引:0,他引:1
《Journal of Adhesion Science and Technology》2013,27(15):1829-1837
Rotationally welded wood dowels were used to hold together step butt and mortise and tenon L-joints and these joints were tested against European Norms for these types of joints. A factorial experiment was carried out in which (1) these two types of joints were tested, (2) 4 or 6 dowels per joint were used, (3) dowels were inserted at either 45° or 90° to the surface of the wood, (4) two types of wood were used, beech and European ash, and (5) two types of tests were carried out, namely compression and tension tests. The strength results were used to find out which of these were the most important individual parameters and their interactions, namely type of joint, number of dowels, and type of test. The strength results were well in excess of the relevant L-joints standard specifications for wooden windows. 相似文献