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11.
A new apparatus has been constructed in which ultrasonic velocity and attenuation coefficients can be measured under oscillatory deformation. Using this apparatus, dynamic ultrasonic parameters were obtained with sufficient accuracy to investigate plastic deformation directly. It is found that this method has potential as a new tool for the study of solid polymers during deformation. 相似文献
12.
Yuki Nitta Keishi Okamoto Tatsuyuki Nakatani Hideo Hoshi Akihiko Homma Eisuke Tatsumi Yoshiyuki Taenaka 《Diamond and Related Materials》2008,17(11):1972-1976
With the purpose of applying diamond-like carbon (DLC) thin films as a biocompatible material, we experimented with introducing functional groups such as amino and carboxyl groups to the surface of DLC thin films by plasma surface treatment. From the results, it was found that the contact angle values of the DLC thin films surface were decreased with increasing in the OCO bonded network on the surface. Measurement of the zeta potential when the amounts of the functional groups were varied showed that this successfully varied the zeta potential over the wide range of − 48 mV to + 12 mV. It was found that when carboxyl groups are introduced by O2 plasma modification of the DLC thin films surface, the zeta potential was lower than that of untreated DLC thin films sample. It was also found that amino groups can be introduced to the DLC thin films surface by NH3 plasma treatment, the zeta potential was higher than that of untreated DLC thin films sample. This means that zeta potential of the DLC thin films can also be controlled by controlling these two functional groups. Therefore, we have succeeded in developing a multifunctional DLC thin films that does not use polymers and is suitable as a biocompatible material. 相似文献
13.
Tanaka Takanori; Miwa Naofumi; Kawamura Satoru; Sohma Hitoshi; Nitta Katsutoshi; Matsushima Norio 《Protein engineering, design & selection : PEDS》1999,12(5):395-405
P26olf from olfactory tissue of frog, which may be involvedin olfactory transduction or adaptation, is a Ca2+-binding proteinwith 217 amino acids. The p26olf molecule contains two homologousparts consisting of the N-terminal half with amino acids 1109and the C-terminal half with amino acids 110217. Eachhalf resembles S100 protein with about 100 amino acids and containstwo helixloophelix Ca2+-binding structural motifsknown as EF-hands: a normal EF-hand at the C-terminus and apseudo EF-hand at the N-terminus. Multiple alignment of thetwo S100-like domains of p26olf with 18 S100 proteins indicatedthat the C-terminal putative EF-hand of each domain containsa four-residue insertion when compared with the typical EF-handmotifs in the S100 protein, while the N-terminal EF-hand ishomologous to its pseudo EF-hand. We constructed a three-dimensionalmodel of the p26olf molecule based on results of the multiplealignment and NMR structures of dimeric S100B(ßß)in the Ca2+-free state. The predicted structure of the p26olfsingle polypeptide chain satisfactorily adopts a folding patternremarkably similar to dimeric S100B(ßß). Each domainof p26olf consists of a unicornate-type four-helix bundle andthey interact with each other in an antiparallel manner formingan X-type four-helix bundle between the two domains. The twoS100-like domains of p26olf are linked by a loop with no sterichindrance, suggesting that this loop might play an importantrole in the function of p26olf. The circular dichroism spectraldata support the predicted structure of p26olf and indicatethat Ca2+-dependent conformational changes occur. Since theC-terminal putative EF-hand of each domain fully keeps the helixloophelixmotif having a longer Ca2+-binding loop, regardless of the four-residueinsertion, we propose that it is a new, novel EF-hand, althoughit is unclear whether this EF-hand binds Ca2+. P26olf is a newmember of the S100 protein family. 相似文献
14.
The effects of morphology on mechanism of plastic deformation are investigated for binary blends of isotactic polypropylene and rubbery ethylene-1-hexene copolymers. In this work, plastic deformation developed during elongation is investigated by measuring light transmittance, electron microscopy, and ultrasonic propagation in the temperature region between 298 K and 353 K. It is found that the compatible blends hardly show stress-whitening at any temperature, whereas the incompatible blends show distinct stress-whitening below 333 K. Furthermore, microscopic defects such as microvoids and crystalline defects are found to be precursors for crazing which are origin of the stress-whitening. 相似文献
15.
Ito M. Nitta K. Ohno K. Saigusa M. Nishida M. Yoshioka S. Irita T. Koike T. Kamei T. Komuro T. Hattori T. Arai Y. Kodama Y. 《Solid-State Circuits, IEEE Journal of》2009,44(1):83-89
Supporting both WCDMA with HSDPA and GSM/GPRS/EDGE, the 9.3 times 9.3 mm2 SoC fabricated in triple-Vth 65 nm CMOS, has three CPU cores and 20 separate power domains. Unused power domains can be powered down to reduce the leakage power. Partial clock activation scheme especially focused on music playback scene dynamically stops a PLL and clock trees when not necessary and reduces power consumption from 33.6 mW to 19.6 mW. IP-MMU translates virtual address to physical address for 18 hardware-IPs and virtual address space can be allocated when necessary and can be freed after its operation, reducing external memory by 43 MB. Video performance of D1 (720 times 520) size with 30 frames per second for MPEG/AVC decoding and encoding can be achieved under mixed virtual and physical address usage. 相似文献
16.
A dynamic optical neurochip with variable synaptic interconnection capability has been reported. A novel type of photodetector called a variable sensitivity photodetector has been developed for the synaptic interconnection of neural networks. It utilizes a metal-semiconductor-metal structure whose quantum efficiency can be modulated by an applied bias voltage. The fabricated dynamic optical neurochip consists of an 8×8 variable sensitivity photodetector (VSPD) array and an 8 line-shaped LED array. It is shown that this device is suitable for learning in neural networks. The application to pattern classification is demonstrated 相似文献
17.
The selective detection of CO gas by stannic oxide incorporated with ThO2(l − 10 wt%), in the presence of H2 and petroleum
gases such as C3H8 and iso-C4H2 has been studied. Materials mixed with 5 wt% ThO2 showed high selectivity to CO gas at a sample temperature of 200−250‡C. The effects of hydrophobic or hydrophilic silica
present in the samples on the detection sensitivity to CO gas have been investigated. From the results it is apparent that
the removal of the hy-droxyl radical from the surface of SnO2 enhances the sensitivity to CO gas. 相似文献
18.
We investigated the correlation between the Rashba spin–orbit coefficient and potential shape of the quantum wells (QW), where values are experimentally deduced from the weak antilocalization analysis. We studied the gate I–V properties of the QW samples and have obtained results consistent with the potential shapes predicted for these QWs. 相似文献
19.
Takashi Itoh Hitoe Habuchi Shoji Nitta Shuichi Nonomura 《Fullerenes, Nanotubes and Carbon Nanostructures》1994,2(2):181-187
Gas effusion spectra of fullerenes are studied. Three peaks of toluene are found in gas effusion spectra dp/dT-T. Two peaks of oxygen are found in gas effusion spectra dN/dt-T of samples kept in the air after annealing to avoid the toluene. These phenomena confirmed to be reversible are discussed by treating fullerenes as intercalated materials. 相似文献
20.
Takatoshi Ohara Yasuhiro Akiyama Koji Nagata Hiroyuki Nitta Yasuyuki Kudo 《Journal of the Society for Information Display》2011,19(1):116-122
Abstract— The plasma‐display panel (PDP) is a type of flat‐panel display that can display a high‐quality image. However, when moving images are displayed, annoying disturbances such as false contour noise occurs. This noise is called dynamic false contour (DFC). To achieve a higher‐quality image, DFC has to be reduced. Therefore, a new method to reduce DFC is proposed. To find a way to reduce DFC, a new evaluation value for it has been defined: the evaluation value of dynamic false contour (EVDFC). This value is defined on the basis of a person's subjective evaluation. By applying this value, the cause that generates DFC can be identified. On the basis of these studies, a new method for reducing DFC by applying frame‐rate control (FRC) with suppression of the side effect is proposed. This improved method can be used to provide high‐quality images. 相似文献