排序方式: 共有97条查询结果,搜索用时 484 毫秒
1.
2.
Ke Li Yingfeng Li Xinyu Wang Mengkui Cui Bolin An Jiahua Pu Jintao Liu Boyang Zhang Guijun Ma Chao Zhong 《国家科学评论(英文版)》2021,8(8)
Marine diatoms construct their hierarchically ordered, three-dimensional (3D) external structures called frustules through precise biomineralization processes. Recapitulating the remarkable architectures and functions of diatom frustules in artificial materials is a major challenge that has important technological implications for hierarchically ordered composites. Here, we report the construction of highly ordered, mineralized composites based on fabrication of complex self-supporting porous structures—made of genetically engineered amyloid fusion proteins and the natural polysaccharide chitin—and performing in situ multiscale protein-mediated mineralization with diverse inorganic materials, including SiO2, TiO2 and Ga2O3. Subsequently, using sugar cubes as templates, we demonstrate that 3D fabricated porous structures can become colonized by engineered bacteria and can be functionalized with highly photoreactive minerals, thereby enabling co-localization of the photocatalytic units with a bacteria-based hydrogenase reaction for a successful semi-solid artificial photosynthesis system for hydrogen evolution. Our study thus highlights the power of coupling genetically engineered proteins and polysaccharides with biofabrication techniques to generate hierarchically organized mineralized porous structures inspired by nature. 相似文献
3.
考虑不可压渗流方程,利用半群e^-t(-d)n算子的性质,研究当初值充分小时,方程的解在空间PM^n+1-2a(Rn)中的整体衰减速率。 相似文献
4.
在室温下,用六水合硝酸锌和对苯二甲酸为原料,通过扩散三乙胺制备了金属有机框架结构(MOF-5)的纳/微米颗粒.通过控制反应体系中水的含量,得到了不同形貌的纳/微米颗粒.通过扫描电子显微镜观察样品MNMOF-6的形貌为纳米颗粒的聚集体,每个纳米颗粒的直径为50-100纳米,样品MNMOF-7,MNMOF-8和MNMOF-9的形貌分别为棒状、针状和带状,我们对不同形貌的MOF-5纳微米颗粒的氮气吸附性能进行了表征. 相似文献
5.
6.
多孔Ni-Ti形状记忆合金在医学和减震方面的应用研究 总被引:2,自引:1,他引:1
在对多孔Ni-Ti形状记忆合金的特点及工程应用须解决的关键问题进行分析的基础上,介绍了该材料的最新研究进展。对多孔Ni-Ti形状记忆合金优良的力学性能、形状记忆效应、超弹性、阻尼特性和生物相容性等特点进行了综述,并对其在医学和减震方面的应用前景和发展趋势进行展望。 相似文献
7.
8.
Al2O3纳米多孔粉体的制备及表征 总被引:1,自引:0,他引:1
邵国强 《浙江教育学院学报》2008,(6):57-61
以异丙醇铝为原料,经过水解、酸解胶、煅烧等过程制得纳米多孔氧化铝,用XRD、SEM、TG/DTA和BET等分析测试技术对产品进行了表征.结果表明,在不使用模板剂的情况下,能够成功制备比表面积较大(124cm^2/g)、孔分布(10~50nm)较集中的纳米多孔氧化铝粉体. 相似文献
9.
Nonlinear bending of cantilever incompressible poroelastic beams subjected to a uniform load is investigated with the constraint that fluid flow is only in the axial direction. The governing equations for large deflection of the poroelastic beam are derived from theory of incompressible saturated porous media. Then, nonlinear responses of a cantilever beam with impermeable fixed end and permeable free end are examined with the Galerkin truncation method. The deflections and bending moments of the poroelastie beam and the equivalent couples of the pore fluid pressures are shown in figures. The differences of the results between the large deflection and the small deflection theories are analyzed. It is shown that the results of the large deflection theory are smaller than those of the small deflection theory, and the time needed to approach their stationary states for the large deflection theory is shorter than that for the small deflection theory. 相似文献
10.
本文分析了开放创新实验——多孔陶瓷实验的教学现状和不足,并根据开放创新实验对学生能力培养、兴趣培养的教育宗旨,提出通过加强学生实验设计自主性、调整实验方法以激发学生参与兴趣、加强小组成员之间的合作、合理评价学生成绩等教改措施,促进多孔陶瓷实验的教学改革与发展。 相似文献