期刊文献+
共找到4篇文章
< 1 >
每页显示 20 50 100
碳纳米管和氧化铝颗粒协同增强铜基复合材料的制备与性能研究 被引量:6
1
作者 张政委 纪箴 +3 位作者 贾成厂 张一帆 唐怡 吕莹莹 《粉末冶金技术》 CAS CSCD 北大核心 2016年第5期356-360,共5页
本文首先利用碱式高锰酸钾对纯化后的CNTs进行改性处理,然后用分子水平法制得前驱体CNTs/Cu复合粉末,最后用内氧化方法,结合放电等离子烧结获得CNTs、Al_2O_3/Cu复合材料。结果表明:CNTs、Al_2O_3/Cu复合材料的维氏硬度(136)和抗拉强度(... 本文首先利用碱式高锰酸钾对纯化后的CNTs进行改性处理,然后用分子水平法制得前驱体CNTs/Cu复合粉末,最后用内氧化方法,结合放电等离子烧结获得CNTs、Al_2O_3/Cu复合材料。结果表明:CNTs、Al_2O_3/Cu复合材料的维氏硬度(136)和抗拉强度(226 MPa)均优于两个增强相单独作用的铜基材料;材料的断后伸长率超过纯铜(40.1%),达到43.6%,表现出非常好的塑性;CNTs和Al_2O_3两个增强相对铜基材料导电率起到了协同增强作用,达到了1+1>2的效果。 展开更多
关键词 铜基复合材料 协同增强 分子水平法 内氧化方 放电等离子烧结
下载PDF
Hydrocarbon Composition of Different VGO Feedstocks and Its Correlation with FCC Product Distribution
2
作者 Song Haitao Jiao Guofeng +3 位作者 Zhu Xinyi Zhou Xiang Zhu Yuxia Da Zhijian 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2013年第1期32-39,共8页
Three different types of VGO were selected and cut into various distillates by true boiling-point distillation (TBD), and the distillates were further separated into different components (saturates, aromatics and r... Three different types of VGO were selected and cut into various distillates by true boiling-point distillation (TBD), and the distillates were further separated into different components (saturates, aromatics and resins) via solid phase extrac- tion (SPE). The hydrocarbon components in saturates and aromatics were characterized on the quasi-molecular level by GC/ MS and CJC/TOF MS. Cracking reactions of VGO, their distillates, and hydrocarbon components (saturates and aromatics) were performed on an ACE (model AP) unit. Nine correlation parameters (mainly based on the previous assumption of basic structure Units, BSU) which could better reflect the structures and compositions of hydrocarbons were put forward based on the quasi-molecular level analysis data, and correlated with FCC product distribution by multi-regression method. A series of correlation formulas were obtained. The formulas were further verified by comparing experimental and calculated FCC yields emanated from two other VGO feedstocks. 展开更多
关键词 fluid catalytic cracking VGO product distribution hydrocarbon composition CORRELATION
下载PDF
免疫因子与人类生殖失败
3
作者 李海燕 许侠 《国外医学情报》 2002年第3期21-28,5,共9页
人类生殖失败可能是妊娠过程中免疫因子异常表达的结果。尽管免疫因子在人类生殖中的相对重要性仍是一个有争议的问题,但已有充分证据表明人类白细胞抗原(HLA)、抗精子抗体、整联蛋白、白细胞抑制因子(LIF)、细胞因子、抗磷脂抗体、子... 人类生殖失败可能是妊娠过程中免疫因子异常表达的结果。尽管免疫因子在人类生殖中的相对重要性仍是一个有争议的问题,但已有充分证据表明人类白细胞抗原(HLA)、抗精子抗体、整联蛋白、白细胞抑制因子(LIF)、细胞因子、抗磷脂抗体、子宫内膜粘附因子、粘蛋白(MUCI)和子宫自然杀伤细胞均与生殖失败有关。相反,几乎没有资料支持胚胎滋养层抗体、抗子宫内膜抗体、T细胞、外周自然杀伤细胞、抗HLA抗体、阻断性抗体和免疫抑制细胞在生殖失败中的作用。尽管传统上已采用抗体/抗原测定来研究与生殖失败有关的免疫因子,但在人体中对这些因子的进一步深入研究却得出了相互矛盾的结果。 展开更多
关键词 免疫因子 不育症 病理 分子水平测定 人类生殖失败 配子发育 胚胎发育
下载PDF
Updating of the hierarchical rock mass rating(HRMR) system and a new subsystem developed for weathered granite formations 被引量:1
4
作者 Miranda Tiago e Sousa L.Ribeiro Tinoco Joaquim 《International Journal of Mining Science and Technology》 SCIE EI 2014年第6期769-775,共7页
The RMR system is still very much applied in rock mechanics engineering context. It is based on the evaluation of six weights to obtain a final rating. To obtain the final rating a considerable amount of information i... The RMR system is still very much applied in rock mechanics engineering context. It is based on the evaluation of six weights to obtain a final rating. To obtain the final rating a considerable amount of information is needed concerning the rock mass which can be difficult to obtain in some projects or project stages at least with accuracy. In 2007 an alternative classification scheme based on the RMR, the Hierarchical Rock Mass Rating(HRMR) was presented. The main feature of this system was the adaptation to the level of knowledge existent about the rock mass to obtain the classification of the rock mass since it followed a decision tree approach. However, the HRMR was only valid for hard rock granites with low fracturing degrees. In this work, the database was enlarged with approximately 40% more cases considering other types of granite rock masses including weathered granites and based on this increased database the system was updated. Granite formations existent in the north of Portugal including Porto city are predominantly granites. Some years ago a light rail infrastructure was built in the city of Porto and surrounding municipalities which involved considerable challenges due to the high heterogeneity levels of the granite formations and the difficulties involved in their geomechanical characterization. In this work it is intended to provide also a contribution to improve the characterization of these formations with special emphasis to the weathered horizons. A specific subsystem applicable to the weathered formations was developed. The results of the validation of these systems are presented and show acceptable performances in identifying the correct class using less information than with the RMR system. 展开更多
关键词 Rock mass classification system Decision tree Weathered granite formations
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部