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Toroidal Protein Adaptor Assembles Ferrimagnetic Nanoparticle Fibers with Constructive Magnetic Coupling 下载免费PDF全文
Tuan Anh Pham Andreas Schreiber Stefan M. Schiller Helmut Cölfen 《Advanced functional materials》2017,27(7)
Inspired by nature, the synthesis of biohybrid nanocomposites containing inorganic nanoparticles (NPs) and biopolymers such as DNA and peptides as templates offers great potential for a wide range of applications. Using selective recognition schemes of 3D protein spaces for the assembly of magnetic nanocrystals is a challenge with great promise in the field of biomedicine and magnetic data storage. Here we apply the toroidal protein Hcp1 as an interparticle connector for the directed molecular assembly and ferrimagnetic coupling of biohybrid cobalt ferrite NP wires. The resulting biohybrid NP composites show bundles of nanofibers ranging from nano‐ to the microscale in length verified by TEM, EDX analysis and focused ion beam cut. Their magnetic characterization reveals an increase of the coercive field (+12%) reaching values of high‐end Nd2Fe14B bulk magnets, enhanced saturation (+28%) and remanence magnetization (+38%) at 2 K compared to NPs lacking the protein connector. Thus, the combination of the nanoscale alignment of magnetic NPs with the molecular precision of the protein connectors leads to constructive addition of the magnetization reversal energy. This approach can be used to control magnetic properties for the design of materials with enhanced coercivity applicable for magnetic data storage, hyperthermia and theranostics. 相似文献
74.
The commenter makes several critical comments concerning the above-named work of B.S. Duran and J.M. Booker (see ibid., vol.37, p.239-47, June 1988). Duran and Booker present a detailed reply, pointing out, among other things, that the commenter is assuming a much more well-defined problem than theirs 相似文献
75.
Hara T. Fukuda K. Kanazawa K. Shibata N. Hosono K. Maejima H. Nakagawa M. Abe T. Kojima M. Fujiu M. Takeuchi Y. Amemiya K. Morooka M. Kamei T. Nasu H. Chi-Ming Wang Sakurai K. Tokiwa N. Waki H. Maruyama T. Yoshikawa S. Higashitani M. Pham T.D. Yupin Fong Watanabe T. 《Solid-State Circuits, IEEE Journal of》2006,41(1):161-169
An 8-Gb multi-level NAND Flash memory with 4-level programmed cells has been developed successfully. The cost-effective small chip has been fabricated in 70-nm CMOS technology. To decrease the chip size, a one-sided pad arrangement with compacted core architecture and a block address expansion scheme without block redundancy replacement have been introduced. With these methods, the chip size has been reduced to 146 mm/sup 2/, which is 4.9% smaller than the conventional chip. In terms of performance, the program throughput reaches 6 MB/s at 4-KB page operation, which is significantly faster than previously reported and very competitive with binary Flash memories. This high performance has been achieved by the combination of the multi-level cell (MLC) programming with write caches and with the program voltage compensation technique for neighboring select transistors. The read throughput reaches 60 MB/s using 16I/O configuration. 相似文献
76.
Mai Lu 《Journal of Infrared, Millimeter and Terahertz Waves》2011,32(1):16-25
This paper presents a numerical study of the electromagnetic wave propagation in a double ridge waveguide, loaded with left-handed
materials (LHM). The LHM is defined phenomenologically by assigning to it a negative permittivity and negative permeability
simultaneously. Transmission characteristics such as cutoff wavelength, single-mode bandwidth, dispersion and field patterns
have been investigated by edge-based finite element method. The results are compared to those with air- and dielectric-loaded
ridge waveguide. It was found that the LHM-loaded ridge waveguide can greatly increase the cutoff wavelength with the disadvantage
of a dramatic reduction in the single-mode bandwidth. The behavior of the dispersion curve of LHM-loaded ridge waveguide is
similar to the cases of waveguide loaded with air or dielectric, except for a significant improvement of the propagation constant.
The boundary conditions at the interface between the air and the LHM have been well illustrated and the antiparallel wave
vector in LHM were obtained by considering the field patterns. The unusual behaviors of the LHM-loaded ridge waveguide provides
the potential opportunities to design novel microwave and millimeter devices. 相似文献
77.
Mai Lu Paul J. Leonard Duo-Wang Fan Fu-Yong Xu 《Journal of Infrared, Millimeter and Terahertz Waves》2004,25(10):1469-1479
In this paper, the cutoff characteristic of rectangular-shaped microshield transmission line has been analysed by edge element method. Dependence of cutoff wavelengths on the thickness of metallic signal strip, dielectric constant of dielectric substrate and the width of the rectangular-shaped ground conductor are presented in tabular form. Numerical results in this paper have important values in design of rectangular-shaped microshield lines in microwave and millimeter wave integrated circuits. 相似文献
78.
Wireless Personal Communications - Cognitive radio networks (CRNs) have a shortcoming in that attackers can increase their ability to disturb secondary users (SUs). This paper focuses on jamming... 相似文献
79.
Hien Thi Thu Pham Yeongsu Kim Young‐Jun Kim Jong‐Won Lee Min‐Sik Park 《Advanced functional materials》2019,29(31)
Given that the performance of a lithium–oxygen battery (LOB) is determined by the electrochemical reactions occurring on the cathode, the development of advanced cathode nanoarchitectures is of great importance for the realization of high‐energy‐density, reversible LOBs. Herein, a robust cathode design is proposed for LOBs based on a dual‐phasic carbon nanoarchitecture. The cathode is composed of an interwoven network of porous metal–organic framework (MOF) derived carbon (MOF‐C) and conductive carbon nanotubes (CNTs). The dual‐phasic nanoarchitecture incorporates the advantages of both components: MOF‐C provides a large surface area for the oxygen reactions and a large pore volume for Li2O2 storage, and CNTs provide facile pathways for electron and O2 transport as well as additional void spaces for Li2O2 accommodation. It is demonstrated that the synergistic nanoarchitecturing of the dual‐phasic MOF‐C/CNT material results in promising electrochemical performance of LOBs, as evidenced by a high discharge capacity of ≈10 050 mAh g?1 and a stable cycling performance over 75 cycles. 相似文献
80.
2020年上半年广东广播电视台新播控中心建设完成,并在下半年投入使用,实现了全台网架构下的制作、新闻与播出一体化,以及全台频道高清化播出、网络化送播和频道一体化编播管理的流程改革。本文主要阐述了全台网架构下,播出整备系统在广东广播电视台的构成与运用。 相似文献