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21.
Taeko Izumi Yoshihiro Yagimuma Masanori Haga 《Journal of the American Oil Chemists' Society》1997,74(7):875-878
Enyzmatic amidation of the primary amines β-alanine ethyl ester and 3-aminopropionitrile with methyl laurate by means of immobilized
lipase (Candida antarctica lipase, CAL) resulted in the formation in good yield of N-lauroyl-β-alanine ethyl ester and 3-(N-lauroylamino)-propionitrile, respectively. When 3-amino-propionitrile was used as substrate, diisopropyl ether was a suitable
solvent. Changing the reaction temperature (12–80°C) did not affect the yields, and room temperature was a suitable temperature
for this reaction. In the investigation of reaction conditions, the use of equimolar amounts (5 mmol) of substrate and ester,
along with 0.5 g of CAL, in diisopropyl ether gave the best yield (99.3%) after 24 h of incubation at 24°C. The enzyme activity
in the amidation reaction did not decrease even after six uses. With β-alanine ethyl ester hydrochloride as substrate, diisopropyl
ether was unsuited as a solvent owing to the low solubility of the substrate in this solvent.
In this reaction, the best yield (82.0%) was attained by using dioxane as solvent. CAL achieved higher extents of amide synthesis
with long-chain than with short-chain ester substrates. The enzyme accepted only nonbulky primary amines as substrates. 相似文献
22.
Ryo Oono 《应用聚合物科学杂志》1977,21(7):1743-1749
The distribution of HAF carbon black in SBR was studied with the electron microscope and Fraunhofer diffraction. The interparticle distance between black aggregates is 8000 Å at 20 phr and 7000 Å at 40 phr, but above 60 phr it spreads broadly in the vicinity of 4000 Å. The size of black aggregates at 20 phr extends from 300 Å to 3000 Å, and the average diameter is 1200 Å. At 40 phr and 60 phr, black trends to aggregate more than at 20 phr and the average diameter is about 1500–1600 Å; the maximum diameter exceeds 5000 Å. In a black aggregate, there are about 40 spherical particles independently of filler concentration. From the relation between the size and interparticle distance, the connection of black aggregates initiates at 40 phr level and affects the physical properties of filled rubber. 相似文献
23.
α-Tocopherol was reacted with methyl linoleateperoxyl radicals at 37°C. The peroxyl radicals were generated by the reaction
of methyl linoleate with a free radical initiator, 2,2′-azobis(2,4-dimethylvaleronitrile). The primary products of α-tocopherol with methyl linoleate-peroxyl radicals were isolated by
reversephase and normal-phase high performance liquid chromatography (HPLC), and their structures were characterized by ultraviolet
(UV), infrared (IR),1H and13C nuclear magnetic resonance (NMR) and mass spectrometry (MS). There were four stereoisomers of methyl 13-(8a-peroxy-α-tocopherone)-9(Z),11(E)-octadecadienoate and four stereoisomers of methyl9-(8a-peroxy-α-tocopherone)-10(E),12(Z)-octadecadienoate. 相似文献
24.
Kosuke Aiuchi Ryo Moriyama Shohei Takeda Shunji Kitada Masaki Onozaki Yukuo Katayama 《Fuel Processing Technology》2007
A pre-heating vaporization technology of coal water slurry, CWS, was developed to increase the efficiency of coal gasification with the reduction of oxygen consumption. A CWS pre-heating experimental unit having a capacity of 2.0 tons-coal/day was manufactured. After the CWS was heated to 573 K at about 10 MPa, water in CWS was continuously vaporized in a tube of which the diameter increased gradually (2–10 mm I.D.), and dry coal particles with steam were atomized and fed to a vessel. No aggregation of coal particles was observed in the atomized samples. The temperature and the pressure distributions of the fluid were calculated with empirical heat transfer and pressure drop correlations. The calculated results well corresponded to the experimental data measured in some test points. Using the calculation model, a large scale apparatus of 100 tons-coal/day was designed using KNO3 + NaNO2 + NaNO3 molten salt as a heating medium. 相似文献
25.
Naoji Shiroma Ryo Miyauchi Akira Nagafusa Youhei Haga Fumitoshi Matsuno 《Advanced Robotics》2015,29(3):149-163
In robot teleoperation, a robot works as a physical agent at a remote site for a robot operator. There are mainly two tasks in robot teleoperation using camera images: environment recognition using visual information and robot control according to the recognition. In this paper, we propose a gaze direction based vehicle teleoperation method with an omnidirectional image stabilization and an automatic body rotation control. In the proposed method, we manage above two tasks in the same manner that are usually treated separately. This method is an intuitive vehicle teleoperation method where an operator do not need to have concern about vehicle body orientations and can absorb differences of vehicle driving mechanisms. That is, this method frees an operator from being bothered from controlling a vehicle and the operator can concentrate on where he/she intends to go. This method mainly consists of two technologies: an omnidirectional image stabilization technology and automatic body rotation control. The conducted experiments show effectiveness of the proposed method. 相似文献
26.
This paper proposes a synthesis method of gain‐scheduled control systems that switch linear time‐invariant controllers according to hysteresis of the scheduling parameter. Stability and L2‐gain analysis and synthesis methods for switched systems are applied to the switched gain‐scheduled control synthesis using reset of the controller state, where also the reset law is computed via linear matrix inequalities (LMIs). In addition to optimization of an upper bound of L2‐gain, we reduce jumps of control input via an auxiliary optimization. Numerical examples are presented to illustrate the switched gain‐scheduled controller. 相似文献
27.
Ryu Komatsu Ryo Nakazato Takeru Sasaki Akio Suzuki Naoyuki Senda Takuya Kawata Yasuhiro Jimbo Tomoya Aoyama Naoto Ohno Susumu Kawashima Hisao Ikeda Shingo Eguchi Yoshiharu Hirakata Shunpei Yamazaki Takashi Shiraishi Seiji Yasumoto Masataka Nakada Masataka Sato Chris Bower Darryl Cotton Andrew Matthews Piers Andrew Catalin Gheorghiu Johan Bergquist 《Journal of the Society for Information Display》2015,23(2):41-49
In this study, a 5.9‐inch foldable active‐matrix organic light emitting diode (AMOLED) display was developed. A folding test was performed repeatedly. The display survived the folding test (100,000 folds) with a curvature radius of 2 mm. To protect an organic light emitting diode (OLED) against moisture, inorganic passivation layers are provided on the upper and lower sides of the flexible display. Using our transfer technology, high density passivation layers can be obtained. The measured water vapor transmission rate of the layer is 7 × 10?6 g/m2?day or less, which improves OLED reliability. With these techniques, we have developed a book‐type display, which is repeatedly foldable like a book, and a tri‐fold display including a display area, which is foldable in three. 相似文献
28.
Nobuhiko Yabu Kouhei Nagano Nozomu Izumi 《Journal of the Society for Information Display》2015,23(6):246-252
Using shorter wavelength for exposure light is one way to achieve high resolution while keeping sufficient depth of focus. We show exposure results for high resolution to confirm the effect of deep UV exposure light. With deep UV light, 1.2‐µm line and space pattern and 1.8‐µm contact hole pattern are resolved while keeping sufficient depth of focus. 相似文献
29.
Bo Zheng Ryo Ishikawa Jun Takamatsu Takeshi Oishi Katsushi Ikeuchi 《Computer Vision and Image Understanding》2013,117(12):1647-1658
A fast registration making use of implicit polynomial (IP) models is helpful for the real-time pose estimation from single clinical free-hand Ultrasound (US) image, because it is superior in the areas such as robustness against image noise, fast registration without enquiring correspondences, and fast IP coefficient transformation. However it might lead to the lack of accuracy or failure registration.In this paper, we present a novel registration method based on a coarse-to-fine IP representation. The approach starts from a high-speed and reliable registration with a coarse (of low degree) IP model and stops when the desired accuracy is achieved by a fine (of high degree) IP model. Over the previous IP-to-point based methods our contributions are: (i) keeping the efficiency without requiring pair-wised correspondences, (ii) enhancing the robustness, and (iii) improving the accuracy. The experimental result demonstrates the good performance of our registration method and its capabilities of overcoming the limitations of unconstrained freehand ultrasound data, resulting in fast, robust and accurate registration. 相似文献
30.
In this paper, we propose a novel method to achieve both dense 3D reconstruction of the scene and estimation of the camera intrinsic parameters by using coplanarities and other constraints (e.g., orthogonalities or parallelisms) derived from relations between planes in the scene and reflected curves of line lasers captured by a single camera. In our study, we categorize coplanarities in the scene into two types: implicit coplanarities, which can be observed as reflected curves of line lasers, and explicit coplanarities, which are, for example, observed as walls of a building. By using both types of coplanarities, we can construct simultaneous equations and can solve them up to four degrees of freedom. To upgrade the solution to the Euclidean space and estimate the camera intrinsic parameters, we can use metric constraints such as orthogonalities of the planes. Such metric constraints are given by, for example, observing the corners of rectangular boxes in the scene, or using special laser projecting device composed of two line lasers whose laser planes are configured to be perpendicular. 相似文献