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991.
Rhombic‐Shaped Nanostructures and Mechanical Properties of 2D DNA Origami Constructed with Different Crossover/Nick Designs 下载免费PDF全文
Zhipeng Ma Yunfei Huang Seongsu Park Kentaro Kawai Do‐Nyun Kim Yoshikazu Hirai Toshiyuki Tsuchiya Hirofumi Yamada Osamu Tabata 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(1)
DNA origami methods enable the fabrication of various nanostructures and nanodevices, but their effective use depends on an understanding of their structural and mechanical properties and the effects of basic structural features. Frequency‐modulation atomic force microscopy is introduced to directly characterize, in aqueous solution, the crossover regions of sets of 2D DNA origami based on different crossover/nick designs. Rhombic‐shaped nanostructures formed under the influence of flexible crossovers placed between DNA helices are observed in DNA origami incorporating crossovers every 3, 4, or 6 DNA turns. The bending rigidity of crossovers is determined to be only one‐third of that of the DNA helix, based on interhelical electrostatic forces reported elsewhere, and the measured pitches of the 3‐turn crossover design rhombic‐shaped nanostructures undergoing negligible bending. To evaluate the robustness of their structural integrity, they are intentionally and simultaneously stressed using force‐controlled atomic force microscopy. DNA crossovers are verified to have a stabilizing effect on the structural robustness, while the nicks have an opposite effect. The structural and mechanical properties of DNA origami and the effects of crossovers and nicks revealed in this paper can provide information essential for the design of versatile DNA origami structures that exhibit specified and desirable properties. 相似文献
992.
Two-dimensional compressible momentum and energy equations are solved on gaseous flows around a micro-scaled gas turbine blade (GE-E3) for which the axial chord length ranges from 86.1 μ m to 86.1 mm to obtain the scale effect. The numerical methodology is based on Arbitrary-Lagrangian-Eulerian (ALE) method. The flow is assumed to be “no heat conduction” flow. The computations were performed for gaseous flow around a single blade with periodical conditions imposed along the boundaries in the pitch directions. The study is focused on the effect of the scale of the turbine blade on the performance. The predicted pressure distribution on both the pressure and suction sides of the conventional sized blade and both the inlet and outlet Mach numbers were compared with available experimental data to verify the code, and the scale effect was discussed. 相似文献
993.
Y Kakihana M Kessler A Krug H Yamada T Oda N Yoshimura 《Canadian Metallurgical Quarterly》1998,56(2):104-112
Modulation of Fas expression and function by CD40 ligation was investigated in the Fas-sensitive human Hodgkin's disease cell line HDLM2. The recombinant human trimeric soluble CD40L (sCD40L) protected this cell line from apoptosis induced by an agonistic Fas antibody at all concentrations tested. sCD40L also protected HDLM2 when added up to 2 h after Fas ligation. Apoptosis induced by a cell-permeable synthetic ceramide could not be prevented by sCD40L. Thus, CD40 ligation is likely to intervene in the early phases of the Fas signal transduction pathway. When CD40 ligation preceded Fas ligation, it rendered the cells refractory to Fas-induced apoptosis. sCD40L-mediated protection could not be attributed to reduction in surface Fas expression, increase in Bcl-2 levels or to increase in the levels of soluble Fas isoforms. 相似文献
994.
Y Oyama KS Hirata T Kajita T Kifune K Kihara M Nakahata K Nakamura S Ohara N Sato M Takita Y Totsuka Y Yaginuma M Mori A Suzuki K Takahashi T Tanimori M Yamada M Koshiba T Suda K Miyano H Miyata H Takei K Kaneyuki Y Nagashima Y Suzuki EW Beier LR Feldscher ED Frank W Frati SB Kim AK Mann FM Newcomer Van Berg R W Zhang 《Canadian Metallurgical Quarterly》1989,39(6):1481-1491
995.
Soliton data signals at 20 Gbit/s have been successfully transmitted over 3000 km with the use of soliton control by synchronous modulation and optical filters. The installation of only one simple modulator makes it possible to extend the maximum transmission distance from 2300 km (without soliton control) to 3000 km which is clearly beyond the Gordon-Haus limit 相似文献
996.
Karasawa Y. Yasukawa K. Yamada M. 《Antennas and Propagation, IEEE Transactions on》1988,36(4):563-569
Radio waves with frequencies above 10 GHz at low-elevation-angle paths are significantly affected not only by rain but also by atmospheric irregularities in the troposphere. The tropospheric scintillation due to irregularities of the refractive index in the troposphere is investigated using 14/11-GHz low-elevation measurements made during 1983 at Yamaguchi, Japan. The diurnal and seasonal variations, frequency dependence derived from a comparison of the 11- and 14-GHz signals, and elevation-angle dependence of the scintillation data are presented. A comparison between the propagation data and ground-level meteorological measurements indicated a high correlation between the scintillation characteristics and the water vapor contribution to the radio refractive index inferred from local humidity and temperature data. This suggests a method for predicting the severity of scintillation fading using local measurements of meteorological parameters 相似文献
997.
A nitrogen (N)-doped diamond-based electron emitter has been fabricated by the sintering technique prior to the chemical vapor deposition process in order to improve the uniformity. There are no spatial differences in reflective electron energy loss spectra (REELS) from the diamond-based electron emitter, suggesting that uniform surface conditions are obtained. The uniform electron emission from the obtained electron emitter is confirmed through emission current vs anode voltage characteristics measurements. It seems that the uniformity of the emitter surface results in uniform electron emission from the diamond electron emitter 相似文献
998.
Hayamizu Y Yamada T Mizuno K Davis RC Futaba DN Yumura M Hata K 《Nature nanotechnology》2008,3(5):289-294
In order to be useful as microelectromechanical devices, carbon nanotubes with well-controlled properties and orientations should be made at high density and be placed at predefined locations. We address this challenge by hierarchically assembling carbon nanotubes into closely packed and highly aligned three-dimensional wafer films from which a wide range of complex and three-dimensional nanotube structures were lithographically fabricated. These include carbon nanotube islands on substrates, suspended sheets and beams, and three-dimensional cantilevers, all of which exist as single cohesive units with useful mechanical and electrical properties. Every fabrication step is both parallel and scalable, which makes it easy to further integrate these structures into functional three-dimensional nanodevice systems. Our approach opens up new ways to make economical and scalable devices with unprecedented structural complexity and functionality. 相似文献
999.
Yoshikazu Takaku Komei Makino Keita Watanabe Ikuo Ohnuma Ryosuke Kainuma Yasushi Yamada Yuji Yagi Ikuo Nakagawa Takashi Atsumi Kiyohito Ishida 《Journal of Electronic Materials》2009,38(1):54-60
The Zn-Al(-Cu) eutectic alloys (melting point 381°C) are candidates for use as Pb-free high-temperature solders as a substitute
for Pb-based solders, which are suitable for severe working environments such as the engine room of hybrid vehicles equipped
with an inverter system as well as a heat engine. In this study, the interfacial reaction between Zn-Al(-Cu) alloys and the
Ni substrate during soldering, aging, and thermal cycling was investigated. Semiconductor chips and Ni substrates were soldered
with Zn-Al(-Cu) alloys at various temperatures under a nitrogen atmosphere. The soldered assemblies were then heat-treated
at 200°C and 300°C to examine the microstructural evolution at the soldered interface. The effect of severe thermal cycles
between −40°C and 250°C in air on the microstructure and fracture behavior at the solder joint was investigated. Even after
a 1000-cycle test, the thickness of the Al3Ni2 layer formed at the interface between the Zn-Al-based solder and the Ni substrate, which is responsible for the damage of
the soldered assemblies, was quite small. 相似文献
1000.
Fukuda M. Ichikawa F. Shuto Y. Sato H. Yamada Y. Kato K. Tohno S. Toba H. Sugie T. Yoshida J. Suzuki K. Suzuki O. Kondo S. 《Lightwave Technology, Journal of》1999,17(9):1585-1592
Low-cost plastic packaging of laser diodes and photodiodes mounted on planar lightwave circuit (PLC) platform are developed and its reliability is confirmed under various environmental and endurance tests. The high performance of the module is maintained under reliability tests, such as high-humidity high-temperature tests (85°C, 85%RH) and temperature cycling tests (-40°C/85°C). No laser diodes show any device characteristics change during environmental tests and their stability has very little dependence on current bias. Although the photodiodes show an increase in leakage current under high-temperature high-humidity tests and the rate of leakage current increase is proportional to the square root of bias voltage, the increase is negligible for system use. These plastic modules can be applied to actual access networks and other fiber-optic networks 相似文献