摘要:
To improve the compatibility between Portland cement and bamboo fibre, bamboo fibres were modified by acetic acid and fermentation treatment and the modified bamboo fibres/Porland cement composites were prepared. The hydration curves of the bamboo fibres/Porland cement composites were measured and the area ratio under the cement hydration heat curve was used as the compatibility coefficient to evaluate the compatibility of bamboo fiber and cement. The hydration products at different hydration times were characterized by XRD, FTIR, and SEM. Moreover, the mechanical strengths of standard test blocks of Portland cement/bamboo fibre composites were tested to further verify the improved compatibility of bamboo fiber and Portland cement. The study shows that the compatibility between bamboo fibre and Portland cement was improved from 9% to 87%, the bending strength of Portland cement/bamboo fibre composite was increased from 638 N to 3678 N, and the compressive strength was increased from 1.5 MPa to 34.35 MPa.
作者机构:
[夏琪琪; 朱凌波; 李新功; 郑霞] College of Material Science and Engineering, Central South University of Forestry & Technology, Changsha;410000, China;[夏琪琪; 朱凌波; 李新功; 郑霞] 410000, China
通讯机构:
[Li, X.] C;College of Material Science and Engineering, Central South University of Forestry & Technology, Changsha, China
作者机构:
[郑霞; 黄清华; 贺正国; 李新功; 高歌] Academy of Materials Science and Engineering, Central South University of Forestry and Technology, Changsha, 410000, China;[谢向荣] Green Construction Technology Group New Building Materials High-Tech Co., Ltd, Changsha, 410000, China
通讯机构:
[Li, X.] A;Academy of Materials Science and Engineering, Central South University of Forestry and Technology, Changsha, China
关键词:
Co4N;d band center;heterogeneous catalysis;hydrogen evolution reaction;transition metals
摘要:
Endowing materials with specific functions that are not readily available is always of great importance, but extremely challenging. Co4N, with its beneficial metallic characteristics, has been proved to be highly active for the oxidation of water, while it is notoriously poor for catalyzing the hydrogen evolution reaction (HER), because of its unfavorable d-band energy level. Herein, we successfully endow Co4N with prominent HER catalytic capability by tailoring the positions of the d-band center through transition-metal doping. The V-doped Co4N nanosheets display an overpotential of 37 mV at 10 mA cm−2, which is substantially better than Co4N and even close to the benchmark Pt/C catalysts. XANES, UPS, and DFT calculations consistently reveal the enhanced performance is attributed to the downshift of the d-band center, which helps facilitate the H desorption. This concept could provide valuable insights into the design of other catalysts for HER and beyond.
作者机构:
[唐钱; 黄清华; 郑霞; 卢立; 潘亚鸽; 朱凌波] School of Materials Science and Engineering, Central South University of Forestry and Technology, Changsha, 410004, China
通讯机构:
[Zheng, X.] S;School of Materials Science and Engineering, Central South University of Forestry and Technology, Changsha, China
作者机构:
[唐钱; 朱凌波; 潘亚鸽; 郑霞; 李新功; 黄清华; 卢立] School of Materials Science and Engineering, Central South University of Forestry and Technology, Changsha, 410004, China
通讯机构:
[Zheng, X.] S;School of Materials Science and Engineering, Central South University of Forestry and Technology, Changsha, China
摘要:
将竹纤维(BF)与聚己内酯(PCL)、聚乳酸(PLA)熔融共混,通过模压工艺制备了PCL/PLA/BF增强复合材料。研究了BF质量分数对该复合材料力学性能、热稳定性以及熔融结晶行为的影响。结果表明:随着BF质量分数的增加,PCL/PLA/BF复合材料的冲击强度、拉伸强度和断裂伸长率均先增大后减小,并均在BF质量分数为40%时达到最大值,分别为11.26 k J/m2、12.68 MPa和5.2%;BF质量分数对PCL/PLA/BF复合材料的热稳定性无明显影响;BF的加入使得复合材料中PCL、PLA共混物的玻璃化转变温度降低,但不同BF质量分数的复合材料玻璃化转变温度变化不大;BF的加入使得复合材料结晶温度小幅提升,但结晶峰强度随着BF质量分数的增加而逐渐减弱。
作者机构:
[Zheng, Xia; Li, Xingong; Pan, Yage; Fu, Bin; Wu, Yiqiang] Cent South Univ Forestry & Technol, Coll Mat Sci & Engn, Changsha, Hunan, Peoples R China.
会议名称:
International Conference on Education and Management with Information Technology (EMIT)
会议时间:
APR 25-26, 2015
会议地点:
Wuhan, PEOPLES R CHINA
摘要:
In this paper, the connotation of innovation education is discussed, the necessity of innovative education in our country and the existing problems in innovative education are analyzed, three necessary factors for cultivation of innovative talents: innovation of education form, innovation of education method and curriculum innovation are introduced, and the connotation and implementation strategy of innovation of education form, innovation of education method and curriculum innovation are expounded, in order to provide certain theoretical support for cultivation of innovative talents in higher education in our country.