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排序方式: 共有529条查询结果,搜索用时 31 毫秒
521.
纳米结构自组装和分子自组装体系 总被引:16,自引:0,他引:16
系统地总结并评述了纳主结构和自组装体系和分子自组装体系的最新进展,介绍了纳米结构自组装和分子自组装的基本概念,总结了几类自组和分子自组装体系的合成方法,例举了这类自组装体系的新特性及与下一代纳米结构器件之间的联系。 相似文献
522.
《Physics letters. [Part B]》1997,415(2):170-174
We present a twisted commutator deformation for N = 1,2 super Virasoro algebras based on GLq(1,1) covariant noncommutative superspace. 相似文献
523.
A generalized F-expansion method is introduced and applied to (3 1)-dimensional Kadomstev-Petviashvili(KP) equation. As a result, some new Jacobi elliptic function solutions of the equation are found, from which the trigonometric function solutions and the solitary wave solutions can be obtained. The method can also be extended to other types of nonlinear evolution equations in mathematical physics. 相似文献
524.
Liqiong Xu 《Journal of Graph Theory》2024,105(3):403-412
Let be a positive integer. A graph is said to be uniformly -connected if between any pair of vertices the maximum number of independent paths is exactly . Dawes showed that all minimally 3-connected graphs can be constructed from such that every graph in each intermediate step is also minimally 3-connected. In this paper, we generalize Dawes' result to uniformly 3-connected graphs. We give a constructive characterization of the class of uniformly 3-connected graphs which differs from the characterization provided by Göring et al., where their characterization requires the set of all 3-connected and 3-regular graphs as a starting set, the new characterization requires only the graph . Eventually, we obtain a tight bound on the number of edges in uniformly 3-connected graphs. 相似文献
525.
The current work combines headspace solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC/MS) with multivariate analysis fusion metabonomics for examining metabolite profile changes. The correlation with metabolic pathways during the fermentation of kombucha tea were comprehensively explored. For optimizing the fermentation process, ultrasound-assisted factors were explored. A total of 132 metabolites released by fermented kombucha were detected by HS-SPME-GC/MS. We employed the principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA) to present the relationship between aroma components and fermentation time, of which the first two principal components respectively accounted for 60.3% and 6.5% of the total variance. Multivariate statistical analysis showed that during the fermentation of kombucha tea, there were significant differences in the phenotypes of metabolites in the samples, and 25 characteristic metabolites were selected as biomarkers. Leaf alcohol was first proposed as the characteristic volatile in the fermentation process of kombucha. Furthermore, we addressed the generation pathways of characteristic volatiles, their formation mechanisms, and the transformational correlation among them. Our findings provide a roadmap for future kombucha fermentation processing to enhance kombucha flavor and aroma. 相似文献
526.
Hao Wang Xianhui Zhang Yonghua Tang Weifeng Rong Jiachen Zhao Chaoyu Fan Zhisen Zhang Zhijun Sun Yun Yang Youhui Lin 《中国化学快报》2023,34(9):108084-346
Functional carbon nanomaterials have become the stars of many active research fields, such as electronics, energy, catalysis, imaging, sensing and biomedicine. Herein, a facile and one-pot strategy for generating ferromagnetic nanoparticles loaded on N-doped carbon nanosheets(Fe-N-CNS) is presented by salt-assisted high-temperature carbonization of natural silk proteins. Due to their graphitic structures,N-doping and ferromagnetic nanoparticles(FeNx, FeOy, FeCz),... 相似文献
527.
528.
Chongxing Li Renbo Liu Shuxian Zhang Qingyu Li Cong Wang Zhiwei Zhang Chengxiang Wang Longwei Yin Rutao Wang 《中国化学快报》2023,34(9):108083-311
Selenium, an element belonging to the same group in the periodic table as sulfur, has a high electronic conductivity(1 × 10-5S/cm) and a high volumetric energy density(3253 mA h/cm3), which is a prospective cathode material for high-energy all-solid-state rechargeable batteries. However, its wide use is hindered by large volume expansion and low utilization rate. In this work, Se-infused nitrogen-doped hierarchical meso-microporous carbon composites(Se/NHPC) are prepared by... 相似文献
529.