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11.
Poly(p-phenylene terephthalamide) (PPTA) was blended with poly(vinyl chloride) (PVC) by solution-blending method. PPTA was metalated for dissolving in dimethyl sulfoxide. Dimethyl sulfoxide was used as a common solvent. In PPTA/PVC composite, PPTA accelerated the thermal degradation of PVC. PPTA molecules are aggregated as microfibrillar form in PVC matrix. Such microfibrils are dispersed homogeneously in PVC matrix, according to polarizing microscopic observation. The average diameter of the microfibrils becomes smaller in the composite with lower content of PPTA. In the surface region of PPTA microfibrils the intermolecular hydrogen bonds between C? Cl of PVC and N? H of PPTA are formed. Young's modulus and the yield stress at room temperature were higher in the composites than those in PVC. The modulus of the composites was higher, especially at the high temperatures above their glass transition temperatures, than that in PVC. The temperature dependence of modulus can be calculated by using the mechanical model equivalent to the quasi-3-dimensional microfibrillar model which will be approximately applied to the composite structure. It becomes apparent that the modulus of the PPTA microfibrils evaluated by using the mechanical model is higher in the higher molecular weight PPTA. 相似文献
12.
Surface‐modified polypropylene (PP) films with thermally and photochemically sensitive copolymers consisting of N‐(2‐hydroxypropyl)methacrylamide (HPMA) and 4‐(4‐methoxyphenylazo)phenyl methacrylate (MPAP), poly(HPMA‐co‐MPAP)‐g‐PP (abbreviated g‐PP) film, were prepared by graft copolymerization with an Ar‐plasma postpolymerization technique. The surfaces of the g‐PP films were characterized by means of X‐ray photoelectron spectroscopy; the percentage grafting of poly(HPMA‐co‐MPAP) with a number‐average molecular weight of 3.28 × 104 was 7.12%, and the molar ratio of HPMA–MPAH in the copolymer was 0.75:0.25. The stimuli‐sensitive adsorption of albumin and polystyrene microspheres on the g‐PP film was also measured. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 143–148, 2003 相似文献
13.
Yasuhiro Jimbo Yuki Tamatsukuri Minato Ito Kohei Yokoyama Yoshiharu Hirakata Shunpei Yamazaki 《Journal of the Society for Information Display》2015,23(7):313-318
To improve the reliability and mechanical durability of a flexible organic light‐emitting diode display, the entire flexible display is coated with an aluminum oxide film by atomic layer deposition (ALD). Because the step coverage of ALD is excellent, the AlOx film was deposited not only on the front and back surfaces but also on the side surfaces of the display. A high‐temperature and high‐humidity preservation test, repetitive bending tests, and a pencil hardness test were conducted on the flexible display with ALD‐AlOx coating. The display survived 500 h of a 65°C, 95% preservation test, endured a 100,000‐time repetitive bending test with a curvature radius of 4 mm, and was found to have a pencil hardness of 4H. 相似文献
14.
Ryu Nakadate Yoshiki MatsunagaJorge Solis Atsuo Takanishi Eiichi MinagawaMotoaki Sugawara Kiyomi Niki 《Mechanism and Machine Theory》2011,46(8):1066-1083
The ultrasound diagnosis of the carotid artery is one of the most common non-invasive methods to detect early stage heart and cerebrovascular diseases. However, the precision and repetitiveness of the probe positioning depend exclusively on the operator's skills and dexterity. For this purpose, we propose the development of a robot assisted system to enhance the accuracy and repetitiveness of the probe positioning to measure the wave intensity (WI) index. In this paper, the Waseda-Tokyo Women's Medical-Aloka Blood Flow Measurement Robot System No. 2 Refined (WTA-2R) is presented. The WTA-2R consists of a conventional ultrasound diagnosis system, a 6-DOFs parallel link slave manipulator, a 6-DOFs serial link passive arm, and a master device. Experiments were carried out to verify its effectiveness in terms of accuracy and required time to perform the task. From the experimental results, the positioning accuracy and reduction of required time were confirmed. 相似文献
15.
Hiroki Kikuchi Shigeki Hashimoto Shinichiro Tajiri Tsuneo Hayashi Yutaka Sugawara Michio Oka Yoshiyuki Akiyama Akira Nakamura Naoya Eguchi 《Journal of the Society for Information Display》2009,17(3):263-269
Abstract— A high‐pixel‐rate, high‐contrast (30,000:1) wide‐color‐gamut grating‐light‐valve laser projector is reported. A new optical engine enabling high‐frame‐rate (240 Hz) scan projection is employed. Panoramic wide‐angle‐scan projection with a 64:9 aspect ratio was also developed. Speckle noise is eliminated using a simple but highly efficient technique. The optical throughput efficiency of the grating‐light‐valve laser projector is reviewed. 相似文献
16.
Artificial Life and Robotics - We propose a class of generalized multiplicative stochastic processes obtained by introducing an endo-perspective into one-dimensional maps with additive noise. We... 相似文献
17.
Nobuyuki?KobayashiEmail author Tsubasa?Wago Yoshiki?Sugawara 《Multibody System Dynamics》2011,26(3):265-281
A method of reducing the system matrices of a planar flexible beam described by an absolute nodal coordinate formulation (ANCF)
is presented. In this method, we focus that the bending stiffness matrix expressed by adopting a continuum mechanics approach
to the ANCF beam element is constant when the axial strain is not very large. This feature allows to apply the Craig–Bampton
method to the equation of motion that is composed of the independent coordinates when the constraint forces are eliminated.
Four numerical examples that compare the proposed method and the conventional ANCF are demonstrated to verify the performance
and accuracy of the proposed method. From these examples, it is verified that the proposed method can describe the large deformation
effects such as dynamic stiffening due to the centrifugal force, as well as the conventional ANCF does. The use of this method
also reduces the computing time, while maintaining an acceptable degree of accuracy for the expression characteristics of
the conventional ANCF when the modal truncation number is adequately employed. This reduction in CPU time particularly pronounced
in the case of a large element number and small modal truncation number; the reduction can be verified not only in the case
of small deformation but also in the case of a fair bit large deformation. 相似文献
18.
Levesque MJ Ichikawa K Date S Haga JH 《Computer methods and programs in biomedicine》2009,93(1):73-82
Grid computing offers the powerful alternative of sharing resources on a worldwide scale, across different institutions to run computationally intensive, scientific applications without the need for a centralized supercomputer. Much effort has been put into development of software that deploys legacy applications on a grid-based infrastructure and efficiently uses available resources. One field that can benefit greatly from the use of grid resources is that of drug discovery since molecular docking simulations are an integral part of the discovery process. In this paper, we present a scalable, reusable platform to choreograph large virtual screening experiments over a computational grid using the molecular docking simulation software DOCK. Software components are applied on multiple levels to create automated workflows consisting of input data delivery, job scheduling, status query, and collection of output to be displayed in a manageable fashion for further analysis. This was achieved using Opal OP to wrap the DOCK application as a grid service and PERL for data manipulation purposes, alleviating the requirement for extensive knowledge of grid infrastructure. With the platform in place, a screening of the ZINC 2,066,906 compound "drug-like" subset database against an enzyme's catalytic site was successfully performed using the MPI version of DOCK 5.4 on the PRAGMA grid testbed. The screening required 11.56 days laboratory time and utilized 200 processors over 7 clusters. 相似文献
19.
K. ôno S. Kobayasi M. Shinohara K. Asahi H. Ishimoto N. Nishida M. Imaizumi A. Nakaizumi J. Ray Y. Iseki S. Takayanagi K. Terui T. Sugawara 《Journal of Low Temperature Physics》1980,38(5-6):737-745
Two-stage nuclear demagnetization has been performed using PrCu6 and Cu as coolants. The Cu nuclear stage reached temperatures as low as 10 K with a rate of temperature rise of less than a few K/h. The corresponding conduction electron temperature is estimated to be less than 50 K. A nuclear orientation thermometer of Al
54Mn has been successfully used to measure temperatures down to 10 K.Supported by the Japan Society for the Promotion of Science. 相似文献
20.
We report the results of electron paramagnetic resonance studies of GdX (X=As, Sb, Bi, S, Se). The temperature dependence of the linewidth H and effective g-factorg
eff are discussed. Values for the Néel temperatureT
N are inferred from coincident anomalies in H andg
eff. In the cases of X=S and Se, our estimates ofT
N are significantly lower than theT
N inferred from static susceptibility measurements. A possible source of the discrepancy is discussed.Supported by the National Science Foundation Grant No. DMR-74-08033.Work performed under the auspices of the U.S. ERDA.Supported by the National Science Foundation. 相似文献