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排序方式: 共有893条查询结果,搜索用时 15 毫秒
81.
Shunsuke Yamamoto Ryusei Miyako Ryota Maeda Yuya Ishizaki Masaya Mitsuishi 《大分子材料与工程》2023,308(10):2300247
Water-resistant poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) films are valuable in biomedical applications; however, they typically require crosslinkers to stabilize the films, which can introduce undesired aggregation or phase separation reactions. Herein, a dipping-based process to prepare PEDOT:PSS films on nonplanar surfaces without crosslinker is developed. Sequential soaking of a dip-coated PEDOT:PSS film in ethanol and water imparts water resistance to the film. Microscopic and spectroscopic techniques are used to monitor the process and confirm that the ethanol soaking elutes the excess PSS from the film bulk, which stabilizes the film prior to the water-soaking process. The obtained films act as conductors and semiconductors on curved surfaces, including 3D-printed objects. A film deposited on a curved surface is successfully applied as the channel layer in a neuromorphic organic electrochemical transistor. This approach can enable integrated bioelectronic and neuromorphic applications that can be readily deployed for facile prototyping. 相似文献
82.
83.
Yuji Fukaishi Yoshihiro Ohta Kohji Higuchi Eiji Takegami Satoshi Tomioka Kosin Chamnongthai 《Artificial Life and Robotics》2012,17(1):1-6
A robust DC?CDC converter which can covers extensive load change and also input voltage changes with one controller is needed. Then the demand to suppress output voltage change becomes still severer. We propose an approximate 2-degree-of-freedom (2DOF) digital controller which realized start-up response and dynamic load response independently. The controller makes a control bandwidth wider, and at the same time makes variations of the output voltage small at sudden changes of a load and an input voltage. In this paper, a new approximate 2DOF digital control system with additional zeros is proposed. Using the additional zeros, the second-order differential transfer characteristics between equivalent disturbances and a output voltage are realized. Therefore, the new controller makes variations of the output voltage smaller and the sudden changes of the load and the input voltage. This controller is actually implement on a DSP and is connected to the DC?CDC converter. Experimental results demonstrate that this type of digital controller can satisfy given severe specifications with low frequency sampling. 相似文献
84.
Biocatalytic Synthesis of Nitriles through Dehydration of Aldoximes: The Substrate Scope of Aldoxime Dehydratases 下载免费PDF全文
Tobias Betke Jun Higuchi Philipp Rommelmann Keiko Oike Dr. Taiji Nomura Prof.Dr. Yasuo Kato Prof.Dr. Yasuhisa Asano Prof.Dr. Harald Gröger 《Chembiochem : a European journal of chemical biology》2018,19(8):768-779
Nitriles, which are mostly needed and produced by the chemical industry, play a major role in various industry segments, ranging from high‐volume, low‐price sectors, such as polymers, to low‐volume, high‐price sectors, such as chiral pharma drugs. A common industrial technology for nitrile production is ammoxidation as a gas‐phase reaction at high temperature. Further popular approaches are substitution or addition reactions with hydrogen cyanide or derivatives thereof. A major drawback, however, is the very high toxicity of cyanide. Recently, as a synthetic alternative, a novel enzymatic approach towards nitriles has been developed with aldoxime dehydratases, which are capable of converting an aldoxime in one step through dehydration into nitriles. Because the aldoxime substrates are easily accessible, this route is of high interest for synthetic purposes. However, whenever a novel method is developed for organic synthesis, it raises the question of substrate scope as one of the key criteria for application as a “synthetic platform technology”. Thus, the scope of this review is to give an overview of the current state of the substrate scope of this enzymatic method for synthesizing nitriles with aldoxime dehydratases. As a recently emerging enzyme class, a range of substrates has already been studied so far, comprising nonchiral and chiral aldoximes. This enzyme class of aldoxime dehydratases shows a broad substrate tolerance and accepts aliphatic and aromatic aldoximes, as well as arylaliphatic aldoximes. Furthermore, aldoximes with a stereogenic center are also recognized and high enantioselectivities are found for 2‐arylpropylaldoximes, in particular. It is further noteworthy that the enantiopreference depends on the E and Z isomers. Thus, opposite enantiomers are accessible from the same racemic aldehyde and the same enzyme. 相似文献
85.
Dr. Ryota Hidese Dr. Kenichi Ataka Dr. Eckhard Bill Dr. Seigo Shima 《Chembiochem : a European journal of chemical biology》2015,16(13):1861-1865
[Fe]‐Hydrogenase (Hmd) catalyzes reversible hydride transfer from H2. It harbors an iron‐guanylylpyridinol as a cofactor with an FeII that is ligated to one thiolate, two COs, one acyl‐C, one pyridinol‐N, and solvent. Here, we report that CuI and H2O2 inactivate Hmd (half‐maximal rates at 1 μM CuI and 20 μM H2O2) and that FeII inhibits the enzyme with very high affinity (Ki=40 nM ). Infrared and EPR studies together with competitive inhibition studies with isocyanide indicated that CuI exerts its inhibitory effect most probably by binding to the active site iron‐thiolate ligand. Using the same methods, it was found that H2O2 binds to the active‐site iron at the solvent‐binding site and oxidizes FeII to FeIII. Also it was shown that FeII reversibly binds away from the active site iron, with binding being competitive to the organic hydride acceptor; this inhibition is specific for FeII and is reminiscent of that for the [FeFe]‐hydrogenase second iron, which specifically interacts with H2. 相似文献
86.
Iwao Matsuya Ryota Tomishi Maya Sato Kiyoshi Kanekawa Yoshihiro Nitta Motoichi Takahashi Satoru Miura Yasutsugu Suzuki Tomohiko Hatada Ryuta Katamura Takashi Tanii Shuichi Shoji Akira Nishitani Iwao Ohdomari 《IEEJ Transactions on Electrical and Electronic Engineering》2011,6(3):266-272
We have developed a novel sensor that enables us to measure the relative story displacement of a building structure in real time. This lateral displacement sensor (LDS) is composed of a light‐emitting diode (LED) array, which is fixed on the ceiling, and a position‐sensitive detector (PSD) unit, which is placed on the floor. We optimized the LDS to achieve high accuracy in lateral displacement measurement. The accuracy was evaluated to be 60 µm by conducting shaking table tests. Two LDSs were implemented in an actual building equipped with an active variable stiffness (AVS) system, and the building was vibrated with seismic waveforms by an exciter placed on the rooftop. The seismic displacement of the second floor relative to the first floor was measured using the LDS. Furthermore, the inclination angle of the second floor could be measured using the LDS during the seismic vibration. Using the AVS system, we realized the residual displacement of the second floor without inducing damage to the building, and succeeded in real‐time residual displacement measurement for the first time. These results indicate that the LDS is useful for the health diagnosis of a building structure. © 2011 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
87.
Nicola Manca Luca Pellegrino Teruo Kanki Warner J. Venstra Giordano Mattoni Yoshiyuki Higuchi Hidekazu Tanaka Andrea D. Caviglia Daniele Marré 《Advanced materials (Deerfield Beach, Fla.)》2017,29(35)
Relaxation oscillators consist of periodic variations of a physical quantity triggered by a static excitation. They are a typical consequence of nonlinear dynamics and can be observed in a variety of systems. VO2 is a correlated oxide with a solid‐state phase transition above room temperature, where both electrical resistance and lattice parameters undergo a drastic change in a narrow temperature range. This strong nonlinear response allows to realize spontaneous electrical oscillations in the megahertz range under a DC voltage bias. These electrical oscillations are employed to set into mechanical resonance a microstructure without the need of any active electronics, with small power consumption and with the possibility to selectively excite specific flexural modes by tuning the value of the DC electrical bias in a range of few hundreds of millivolts. This actuation method is robust and flexible and can be implemented in a variety of autonomous DC‐powered devices. 相似文献
88.
Yu Matsuda Toru Uchida Suguru Suzuki Ryota Misaki Hiroki Yamaguchi Tomohide Niimi 《Microfluidics and nanofluidics》2011,10(1):165-171
For the development of micro- and nano-technology, it has been strongly desired to understand thermo-fluid phenomena inside
or around micro- and nano-devices. An optical measurement technique based on the absorption and the emission of photons by
molecules is useful for experimental analyses of thermo-fluid phenomena of micro and nanoflows. The pressure-sensitive paint
(PSP) technique is a potential diagnostic tool for pressure measurements of micro/nano gas flows because it works as a so-called
“molecular sensor”. However, the micro-scale measurement of PSP has been limited by the aggregation of the luminescent molecules
and their thick film due to the use of a polymer binder. In our previous work, we adopted the Langmuir–Blodgett (LB) technique
to fabricate pressure-sensitive molecular film (PSMF) with ordered molecular assemblies, and investigated properties of PSMF.
In this study, a novel approach to enhance the luminescent intensity of PSMF is proposed, and the pressure distribution in
a micro-nozzle is successfully measured by using PSMF. Moreover, we compared the pressure distribution measured by PSMF with
that numerically analyzed by the direct simulation monte carlo (DSMC) method, showing good agreement with each other. 相似文献
89.
Laboratory and field experiment results for a two-step cell search algorithm using scramble code masking for intercell asynchronous W-CDMA mobile radio are presented. The scramble code is masked at different time positions during each scramble period in the forward link common control channel (CCH) for scramble code timing detection at the mobile receiver. 16 scramble codes are used. The cell search time achievable with the authors' recently proposed three-step cell search algorithm is estimated from the experimental results; cell search can be accomplished within ~960 ms at a probability of 93% in the case of 512 scramble codes and 16 scramble code groups 相似文献
90.
Ryota Kato Yasunari Yoshitomi Taro Asada Masayoshi Tabuse 《Artificial Life and Robotics》2010,15(1):10-16
The purpose of this study was to develop a system for communication between a human and a computer generated (CG) character
to make him or her more peaceful and cheerful. Nonverbal communication using such things as facial expression, a nod, or a
hand gesture is very important for reciprocal communication between humans. In this study, an image registered by infrared
rays which describes the thermal distribution of the face and neck has been used to develop a system for communication between
a human and a CG character. The CG character can synchronize its nod with a person’s nod by predicting his or her nod angle.
The measured feature parameter is input to a fuzzy algorithm system to obtain the nod angle of a person in front of an infrared
camera, and then a moving-average model is used to predict the nod angle of the person. The average error of the nod angle
obtained by the system has been estimated as about 5°. The CG character nods its head, not only when the human nods his or
her head, but also when the human shakes his or her head to the left or right. 相似文献