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金刚石复合片合成材料和工艺研究进展 被引量:4
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作者 杨雄文 冯枭 +4 位作者 王旭 ChrisCheng JiaqingYu 彭齐 柯晓华 《超硬材料工程》 CAS 2021年第6期34-41,共8页
催化剂/粘合剂在金刚石复合片压制过程中用来催化聚晶金刚石颗粒间形成金刚石键,并将聚晶金刚石与碳化钨基体粘结在一起,是金刚石复合片合成的重要材料。传统的钴催化剂/粘合剂在高温钻井作业中不仅会与金刚石热膨胀不匹配从而产生残余... 催化剂/粘合剂在金刚石复合片压制过程中用来催化聚晶金刚石颗粒间形成金刚石键,并将聚晶金刚石与碳化钨基体粘结在一起,是金刚石复合片合成的重要材料。传统的钴催化剂/粘合剂在高温钻井作业中不仅会与金刚石热膨胀不匹配从而产生残余应力,还会催化金刚石发生热降解,影响了金刚石复合片的性能。论文阐述了钴催化剂/粘合剂对金刚石复合片合成的影响机理,并总结了前人在改进金刚石复合片合成用催化剂/粘合剂以及合成工艺方面的尝试。研究表明,含碳或硅元素的合金、镍基合金、铌等金属催化剂/粘合剂替代材料以及碳化硅、六方氮化硼、碳酸镁等非金属催化剂/粘合剂替代材料能够通过增强金刚石—基体以及金刚石之间的连结、减少热膨胀不匹配、抑制金刚石石墨化、延缓金刚石氧化等不同方式提高金刚石复合片的耐磨性、抗冲击性和热稳定性。“三层法”、减少碳/钨比、包裹金刚石颗粒等新合成工艺亦能提高金刚石复合片的使用寿命。通过提高金刚石复合片合成的温度和压力、拓宽石墨—金刚石转化条件能够在无催化剂条件下压制金刚石复合片,大幅提升金刚石复合片的硬度、断裂韧性和耐磨性。建立标准化度量指标和测试程序、建立材料数据库和金刚石复合片性能预测模型以及深入探索无催化金刚石复合片合成是金刚石复合片合成未来发展方向。 展开更多
关键词 金刚石复合片 催化剂粘合剂 热膨胀不匹配 金刚石石墨化 无催化合成
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水相中无催化剂合成四氢苯并吡喃衍生物(英文) 被引量:2
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作者 包志坚 纪顺俊 陆军 《合成化学》 CAS CSCD 2007年第5期630-633,共4页
水相中无催化剂合成了2-氨基-7,7-二甲基-5-氧代-4-芳基-4H-苯并吡喃-3-氰基-5,6,7,8-四氢苯并[b]吡喃,其结构经1H NMR,IR和元素分析表征。
关键词 苯并[b]吡喃 环境友好 无催化剂合成
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Nitrogen-doped graphene approach to enhance the performance of a membraneless enzymatic biofuel cell
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作者 Alireza AHMADIAN YAZDI Jie XU 《Frontiers in Energy》 SCIE CSCD 2018年第2期233-238,共6页
Heteroatom-doping of pristine graphene is an effective route for tailoring new characteristics in terms of catalytic performance which opens up potentials for new applications in energy conversion and storage devices.... Heteroatom-doping of pristine graphene is an effective route for tailoring new characteristics in terms of catalytic performance which opens up potentials for new applications in energy conversion and storage devices. Nitrogen-doped graphene (N-graphene), for instance, has shown excellent performance in many electrochemical systems involving oxygen reduction reaction (ORR), and more recently glucose oxidation. Owing to the excellent H2O2 sensitivity of N-graphene, the development of highly sensitive and fast-response enzymatic biosensors is made possible. However, a question that needs to be addressed is whether or not improving the anodic response to glucose detection leads to a higher overall performance of enzymatic biofuel cell (eBFC). Thus, here we first synthesized N-graphene via a catalyst-free single-step thermal process, and made use of it as the biocatalyst support in a membraneless eBFC to identify its role in altering the performance characteristics. Our findings demonstrate that the electron accepting nitrogen sites in the graphene structure enhances the electron transfer efficiency between the mediator (redox polymer), redox active site of the enzymes, and electrode surface. Moreover, the best performance in terms of power output and current density of eBFCs was observed when the bioanode was modified with highly doped N-graphene. 展开更多
关键词 enzymatic fuel cell nitrogen-doped graphene reduced graphene oxide catalyst-free synthesis
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