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31.
Improvement in impact strength of modified cardanol‐bonded cellulose thermoplastic resin by adding modified silicones
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The impact strength of cellulose diacetate (CDA) bonded with a modified cardanol (3‐pentadecylphenoxy acetic acid: PAA) was greatly improved up to 9 kJ/m2 by adding a relatively small amount of modified silicones while suppressing a decrease in bending strength. In our recent research, this thermoplastic resin (PAA‐bonded CDA) exhibited high rigidity, glass transition temperature, and water resistance. However, its impact strength was insufficient for use in durable products. Therefore, silicones modified with polyether, amino, and epoxy groups were investigated as possible ways to improve the impact strength. The results show that adding polyether‐modified silicone (polyether silicone) with moderate polarity relative to PAA‐bonded CDA resulted in shearing deformation greatly enhances its impact strength while maintaining other properties, including glass transition temperature (Tg), water resistance, and thermoplasticity. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40366. 相似文献
32.
The diffusion coefficient (D) values of tert‐butyloxycarbonyl‐glycine, tert‐butyloxycarbonyl‐L ‐tryptophan, tert‐butyloxycarbonyl‐L ‐phenylalanine (Boc‐Phe), and 9‐fluorenylmethoxycarbonyl‐L ‐phenylalanine in Merrifield polystyrene (MPS) gels, poly(ethylene glycol)‐grafted polystyrene (PEG–PS) gels, and crosslinked ethoxylate acrylate (CLEAR) gels, as used in solid‐phase peptide synthesis, were determined by the pulsed‐field‐gradient spin‐echo 1H‐NMR method. From these experimental results, it was found that the amino acids in MPS gels, PEG–PS gels, and CLEAR gels with N,N‐dimethylformamide‐d7 (DMF‐d7) as a solvent had multidiffusion components within a measurement timescale of 10 ms. The D value of Boc‐Phe in polystyrene gels (1% divinylbenzene crosslinked) with tetrahydrofuran‐d8 was much larger than that in the same gels with DMF‐d7. Furthermore, the required time in which an amino acid transferred from a reactive site to a reactive site was estimated, within which the solvents and amino acids in the polymer supports diffused in the swollen beads.© 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 413–421, 2003 相似文献
33.
Yoshihiro Ichikawa Shigeki Obote Kenichi Kagoshima 《Wireless Personal Communications》2005,35(4):353-364
A tapped delayed line adaptive array antenna (TDL-AAA) and a space-temporal simultaneous processing equalizer (ST-SPE) are
proposed as simple space-temporal equalizers based on minimum mean square error (MMSE) criterion. The ST-SPE has a compact
hardware with a small number of taps compared to that of the TDL-AAA. The ST-SPE can reduce the computational complexity of
the space-temporal joint equalization and it works effectively under the minimum phase condition such as appeared at line-of-sight
(LOS) propagation environments at a high antenna height base station. However the ST-SPE cannot work under a non-minimum phase
condition caused under N-LOS (non-line-of-sight). On the other hand, the TDL-AAA whose reference signal is synchronized at
the center tap (TDL-AAAC) can work even in the non-minimum phase condition. In this paper, we propose a dual-mode space-temporal simultaneous processing
equalizer (Dual-mode ST-SPE) which has a simple configuration and also works in non-minimum phase condition. The Dual-mode
ST-SPE can reduce the computational complexity compared to the TDL-AAAC.
Yoshihiro Ichikawa received the B.E. degree in department of communication engineering, in National Defense Academy in 1995, and M.E. and D.E.
degree from Ibaraki University in 2001 and 2004, respectively. He joined the Japan Air Self Defense Force in 1995. His research
interests are an adaptive algorithm, an antenna design, and an adaptive array antenna.
Shigeki Obote received his B.E., M.E. and D.E. degrees in electrical and electronic engineering from Tottori University, Tottori, Japan,
in 1996, 1998 and 2000, respectively. Since 2000, he has been with department of media and telecommunications engineering,
faculty of engineering, Ibaraki University, Ibaraki, Japan, where he is currently a associate professor. His research interests
are in adaptive array antenna and wireless communications systems.
Kenichi Kagoshima received the B.E., M.E. and D.E. degrees in electronics engineering from the Tokyo Institute of Technology, Tokyo, Japan,
in 1969, 1971, and 1974, respectively. He joined the Nippon Telegraph and Telephone Corporation (NTT) Laboratory in 1974 and
researched and developed many kinds of radio communication antennas. Since 1997, he has been a professor at Ibaraki University,
Ibaraki, Japan. Dr. Kagoshima was a Secretary and Treasure, Vice Chairman, and Chairman of the IEEE AP-S Tokyo Chapter in
1992, 1993, and 1994, respectively. He was a chair of antennas and propagation professional group of IEICE in 1999 and 2000.
In 1973, he received the Yonezawa Prize for Young Engineers and 1998, best paper award from IEICE, respectively. 相似文献
34.
C. Alcoholado M. Nussbaum A. Tagle F. Gomez F. Denardin H. Susaeta M. Villalta K. Toyama 《Journal of Computer Assisted Learning》2012,28(4):295-309
Single Display Groupware (SDG) allows multiple people in the same physical space to interact simultaneously over a single communal display through individual input devices that work on the same machine. The aim of this paper is to show how SDG can be used to improve the way resources are used in schools, allowing students to work simultaneously on individual problems at a shared display, and achieve personalized learning with individual feedback within different cultural contexts. We used computational fluency to apply our concept of ‘One Mouse per Child’. It consists of a participatory approach that makes use of personal feedback on an interpersonal computer for the whole classroom. This allows for N simultaneous intelligent tutoring systems, where each child advances at his or her own pace, both within a lecture and throughout the curricular units. Each student must solve a series of mathematical exercises, generated according to his or her performance through a set of pedagogical rules incorporated into the system. In this process, the teacher has an active mediating role, intervening when students require attention. Two exploratory studies were performed. The first study was a multicultural experience between two such distanced socio‐economic realities as Chile and India. It showed us that even in different environmental conditions, it is possible to implement this technology with minimal equipment (i.e. a computer, a projector, and one mouse per child). The second study was carried out in a third grade class in a low‐income school in Santiago de Chile. The students were asked to solve mainly addition exercises. We established statistically relevant results and observed that the software proved most beneficial for the students with the lowest initial results. This happens because the system adapts to the students' needs, reinforcing the content they most need to work on, thus generating a personalized learning process. 相似文献
35.
Yannhui Lou Yuta Okawa Zhaokui Wang Shigeki Naka Hiroyuki Okada 《Organic Electronics》2013,14(3):1015-1020
The electron transport capability of 4,4′-bis[N-(1-napthyl)-N-phenyl-amino] biphenyl (α-NPD) was investigated by fundamental physical measurements named as current–voltage (I–V) electrical property evaluation and displacement current measurement (DCM). In electron-dominated devices, the I–V characteristics of α-NPD were similar as that of (8-hydroxyquinolino) aluminum (Alq3) owing to their same order of electron mobilities. The interface of Al/LiF and α-NPD was proven to be an Ohmic contact through the evaluation of I–V characteristics at low bias regime (<3 V). And an electron injection barrier, 0.21 eV, at Al/LiF/α-NPD was obtained by extrapolating the temperature dependent I–V curves. The electron transport behavior in α-NPD film was further confirmed by DCM evaluations. Furthermore, an efficient white organic light emission device was successfully fabricated by using α-NPD as hole transport layer and electron transport layer, respectively. 相似文献
36.
Paule Njiwa Clotilde Minfray Thierry Le Mogne Béatrice Vacher Jean-Michel Martin Shigeki Matsui Masaru Mishina 《Tribology Letters》2011,44(1):19-30
In this study, we are interested in the anti-wear properties of zinc dialkyl phosphate additive (ZP) in comparison with ‘classical’ zinc dialkyldithiophosphate (ZDDP). Friction tests were performed on a reciprocating tribometer using both ball-on-flat and cylinder-on-flat configurations
under a Hertzian contact pressure of 0.9 GPa. Experiments were carried out as a function of temperature (25 and 100 °C), sliding
speed (25, 50 and 100 mm/s) and additives concentrations. Ball wear scar diameters as well as friction coefficient were measured.
In order to better understand the anti-wear mechanisms of these additives, friction tests were followed by surface analyses
such as AES (Auger Electron Spectroscopy) and XPS (X-Ray Photoelectron Spectroscopy). Transmission Electron Microscopy (TEM)
observations of the ZDDP and ZP tribofilms were also carried out to visualise the generated layers. The anti-wear capability of ZP molecule is discussed. 相似文献
37.
The objective of this article is to present an efficient extension ofRosenthal's order-n algorithm to multibody systems containing closedloops. The equations of motion are created by using relative coordinatesand partial velocity theory. Closed topological loops are handled by cutjoint technique. The set of constraint equations of cut joints isadjoined to the system's equation of motion by using Lagrangemultipliers. This results in the equation of motion as adifferential-algebraic equation (DAE) rather than an ordinarydifferential equation. This DAE is then solved by applying the extendedRosenthal's order-n algorithm proposed in this article. While solvingDAE, violation of the kinematic constraint equations of cut joints iscorrected by coordinate projection method. Some numerical simulationsare carried out to demonstrate efficiency of the proposed method. 相似文献
38.
Today, firms are facing many contradictions: efficiency versuscreativity; exploitation versus exploration; speed versus time-consumingresource building. This paper argues that a firm's capabilityto synthesize such contradictions is the key to understandingwhy a firm can be more efficient at producing knowledge thanmarket. A firm can create new knowledge and capability thatgo beyond the balancing point in the existing frontier withits synthesizing capability, which is embedded in its knowledgevision, its ba, its creative routines, its incentive systemsand its distributed leadership. 相似文献
39.
Shigeki Harada Akihiko Iwata Heiju Uchiike 《Journal of the Society for Information Display》2005,13(6):537-543
Abstract— In order to lower development costs and to shorten development time, small panels, under 10‐in on the diagonal, are used for the experiments to improve the luminous efficiency of plasma‐display panels. However, it is difficult to show the same results as those of large panels, over 40 in. on the diagonal. In this paper, first, we show that the luminous efficiency and the voltage margin of mini‐panels are not obtained with large panels by using an actual 46‐in. PDP. The reason is that the resistance in the large panels is larger than that in the mini panels and the voltage drop in the large panels are larger than in mini‐panels. Therefore, we conclude that the bus electrode width and the transparent electrode width are important factors in the design of large PDPs. Next, we show the technique of designing large panels by using a database obtained from mini‐panels. The estimated cell‐design results show good agreement with an actual 46‐in. PDP in luminous efficiency and minimum sustain voltage. We show that a desired large PDP can be obtained by using the cell design proposed in the present paper. 相似文献
40.
Shigeki Akiyama Frdrique Bassino Christiane Frougny 《Information and Computation》2005,201(2):199-215
Non-standard number representation has proved to be useful in the speed-up of some algorithms, and in the modelization of solids called quasicrystals. Using tools from automata theory we study the set of β-integers, that is, the set of real numbers which have a zero fractional part when expanded in a real base β, for a given β > 1. In particular, when β is a Pisot number — like the golden mean —, the set is a Meyer set, which implies that there exists a finite set F (which depends only on β) such that . Such a finite set F, even of minimal size, is not uniquely determined.In this paper we give a method to construct the sets F and an algorithm, whose complexity is exponential in time and space, to minimize their size. We also give a finite transducer that performs the decomposition of the elements of as a sum belonging to . 相似文献