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131.
132.
A thermodynamic calculation of the Al-Mn binary system that takes into account recent experimental results and includes five intermetallic compounds and all the solid-solution phases is presented. The Gibbs energy of the body-centered cubic (bcc) phase has been described on the basis of the two-sublattice model that includes the second-order A2/B2 ordering reaction as well. A consistent set of optimized thermodynamic parameters has been arrived at for describing the Gibbs energy of each phase in this system leading to a better fit between calculation and experiments. 相似文献
133.
Yamaguchi K. Ohnuma S. Imagawa T. Toriu J. Matsuki H. Murakami K. 《IEEE transactions on magnetics》1993,29(5):2232-2237
A thin-film 3.14-mm×3.88-mm microtransformer has been fabricated, using photolithography technology, to support high-frequency switching regulators. The microtransformer is composed of sputtered amorphous magnetic layers, electroplated copper windings with 20-μm width, and insulator layers. The coupling factor between the primary and secondary windings of the microtransformer is 0.97 for f =3 MHz. An input-output voltage ratio of 0.95 at 15 MHz is obtained at no-load. Observation of the domain images under high-frequency excitation indicates that the magnetic anisotropy of the microtransformer films is induced by rotating magnetic field annealing so as to increase the output voltage 相似文献
134.
Ikuo Taniguchi William A Kuhlman Anne M Mayes Linda G Griffith 《Polymer International》2006,55(12):1385-1397
This paper presents an overview of functional modifications of synthetic aliphatic polyesters and a new synthetic route to graft functional moieties onto the polyester backbone by a chemoselective approach. Aminooxy groups react efficiently and selectively with ketones or aldehydes to form oxime linkages under mild reaction conditions without catalysts, even in the presence of other functional groups. Chemoselective coupling of aminooxy‐terminated poly(ethylene oxide) (PEO) onto ketone‐bearing poly(ε‐caprolactone) (PCL) was exploited to prepare comb‐shaped copolymers that exhibit cell resistance when the PEO content is above 30 wt%. The free hydroxyl groups of PEO chain ends allowed further incorporation of cell signaling peptides including the sequence RGD. The results show chemoselective coupling to be a promising general route for introducing functional pendant groups onto most polyesters obtained by ring‐opening polymerization without backbone degradation. Copyright © 2006 Society of Chemical Industry 相似文献
135.
The ductile instability characterization of medium density polyethylene (MDPE) has been studied with theJ integralR curve method. The loading of variously notched samples in three-point bending using a compliant test fixture showed that
sudden unstable cracking occurred after the commencement of stable ductile cracking. The tearing modulus which is obtained
from theR curve can describe the transition from stable to unstable crack. Instability occurs when an applied situation depending on
loading system and/or sample geometry exceeds the tearing modulus of MDPE. 相似文献
136.
Creep properties of Sn-8Mass%Zn-3Mass%Bi lead-free alloy 总被引:3,自引:0,他引:3
The creep properties of Sn-8mass%Zn-3mass%Bi were investigated and compared with those of other lead-free solders and a Sn-Pb
eutectic solder. The creep rupture time decreases with increasing the initial stress and the temperature. For high stresses,
the linear relationships between the minimum strain rate and the applied stress were observed. The stress exponents were examined
to be 9.3, 7, and 4 at 298 K, 348 K, and 398 K, respectively. For low stresses, the minimum creep rate becomes relatively
fast, and the creep resistance diminishes. In this range, secondary creep reduces, and the tertiary creep predominates. The
creep properties of Sn-8Zn-3Bi are similar to those of Sn-Ag alloys at high stresses and those of Sn-0.5Cu at low stresses. 相似文献
137.
Yoshikazu Takaku Ikuo Ohnuma Ryosuke Kainuma Yasushi Yamada Yuji Yagi Yuji Nishibe Kiyohito Ishida 《Journal of Electronic Materials》2006,35(11):1926-1932
Bismuth and its alloys are candidates for Pb-free high-temperature solders that can be substituted for conventional Pb-rich
Pb−Sn solders (melting point (mp) = 573 – 583 K). However, inferior properties such as brittleness and weak bonding strength
should be improved for practical use. To that end, BiCu−X (X=Sb, Sn, and Zn) Pb-free high-temperature solders are proposed.
Miscibility gaps in liquid BiCu−X alloys were surveyed using the thermodynamic database ADAMIS (alloy database for micro-solders),
and compositions of the BiCu−X solders were designed on the basis of calculation. In-situ composite solders that consist of
a Bi-base matrix with fine intermetallic compound (IMC) particles were produced by gas-atomizing and melt-spinning methods.
The interfacial reaction between in-situ composite solders and Cu or Ni substrates was investigated. The IMCs at the interface
formed a thin, uniform layer, which is an appropriate morphology for a reliable solder joint. 相似文献
138.
139.
140.
Hanxi?ZhuEmail author Ikuo?Yoshihara Kunihito?Yamamori Moritoshi?Yasunaga 《Artificial Life and Robotics》2004,8(2):168-173
Prediction of protein secondary structure is considered to be an important step toward elucidating the three-dimensional structure
and function of proteins. We have developed a multimodal neural network (MNN) to predict protein secondary structure. The
MNN is composed of several subclassifiers for single-state predictions using neural networks and a decision neural network
(DNN). Each subclassifier employs a number of subnetworks to predict the single-state of the secondary structure individually
and produces the final results by majority decision. The DNN uses a three-layer neural network to produce the final overall
prediction from the outputs of the single-state predictions. The MNN gives an overall accuracy of 71.1% with corresponding
Matthews correlation coefficients of CH = 0.62 and CE = 0.53. The prediction test is based on a database of 126 nonhomologous protein sequences.
This work was presented, in part, at the 8th International Symposium on Artificial Life and Robotics, Oita, Japan, January
24#x2013;26, 2003. 相似文献