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991.
Temperature Dependence of Electrical and Thermal Conductivities of an Epoxy-Based Isotropic Conductive Adhesive 总被引:1,自引:0,他引:1
Masahiro Inoue Hiroaki Muta Takuji Maekawa Shinsuke Yamanaka Katsuaki Suganuma 《Journal of Electronic Materials》2008,37(4):462-468
The temperature dependence of the transport properties, including electrical and thermal conductivities, of a practical isotropic
conductive adhesive (ICA) including an epoxy-based binder was investigated in order to comprehensively evaluate the physical
changes induced during exposure to elevated temperatures. The ICA specimens were cured and post-annealed under various conditions
in order to clarify the effect of curing state of the adhesive binder on the electrical resistivity. The electrical resistivity
at ambient temperature tends to decrease with increasing curing temperature, even if the samples exhibit full conversion.
In addition, an annealing effect, resulting in a deviation from a linear relationship in the temperature dependence of resistivity,
can be induced during the heating process experienced during resistivity measurements. However, the ICA specimens exhibited
similar values for the temperature coefficient of resistivity (TCR), regardless of the curing and post-annealing conditions
in the temperature range where the annealing effect is rarely induced, although the thermal history of the specimens significantly
influences the absolute values of electrical resistivity. The temperature dependence of the thermal conductivity is almost
accounted for by the decrease in the contribution of conducting electrons in the temperature range below the glass-transition
temperature, T
g. 相似文献
992.
Tomoya Inoue Yuta Nemoto Takako Nagase Yasuhisa Hasegawa Yoshimichi Kiyozumi Koichi Sato Masateru Nishioka Satoshi Hamakawa Toshikazu Nishide Fujio Mizukami 《Korean Journal of Chemical Engineering》2008,25(3):437-442
We successfully developed zeolite membranes with hydrophilic character, by choosing appropriate zeolites in terms of hydrophilicity
and high acid tolerance. We evaluated thus developed membranes by their pervaporation (PV) performance, dehydration from acidic
organic solvent. The zeolite membranes we developed, based on merlinoite (MER), chabazite (CHA) or phillipsite (PHI), are
shown to exhibit stable dehydration performance, respectively. We successfully applied the membranes to the selective removal
of water in an ester condensation reaction starting from a stoichiometric mixture of a carboxylic acid and an alcohol. The
availability of pervaporation-assisted ester condensation reaction was validated by various kinds of combinations of carboxylic
acid and alcohols, which implies the general availability of pervaporation-assisted process intensification by zeolite membranes.
This paper was presented at the 11th Korea-Japan Symposium on Catatysis held at Seoul, Korea, May 21–24, 2007. 相似文献
993.
Xianqing Piao Shinichiro Inoue Shiyoshi Yokoyama Hideki Miki Isao Aoki Akira Otomo Hidehisa Tazawa 《Thin solid films》2009,518(2):481-484
We prepared the side-chain electro-optic polymers by the active bonding of cyanate- and hydroxy-functional groups, and employed these side-chain polymers as hosts for the bi-chromophore system to enhance the electro-optic coefficient (r33). In singular chromophore polymer (in PMMA host), the dependence of EO response on loading concentration was examined, r33 about 26 pm/V was obtained. In order to further incorporate the chromophore, the loading behavior in binary chromphore systems was investigated. The optimal r33 more than 40 pm/V was achieved, which was almost the sum of two individual polymers. Furthermore, the temporal stability at room temperature and 85 °C, respectively, over 500 h was evaluated for the potential application on electro-optic devices. 相似文献
994.
Motomichi Inoue Sergio Cantua Felipe Medrano Koichi Asano Masanobu Nakamura 《Polymer Bulletin》1992,28(1):29-32
Summary Diphenylmethane underwent oxidative coupling in the presence of di-t-butyl peroxide and formed 1,1,2,2-tetraphenylethane. This coupling reaction resulted in the formation of a copolymer of diphenylmethane andp-xylene. The new copolymer was soluble in common organic solvents and had a molecular weight of 32,000 (polystyrene base).On leave from Cosmo Oil Co., Japan, under a contract with the Japan International Cooperation Agency 相似文献
995.
Y Uehara M Sasaguri A Kinoshita E Tsuji H Kiyose H Taniguchi K Noda M Ideishi J Inoue K Tomita K Arakawa 《Canadian Metallurgical Quarterly》1998,16(8):1131-1135
BACKGROUND: Liddle's syndrome is an autosomal inheritable disorder that causes hypertension due to excess function of sodium channel. OBJECTIVE: To analyze the DNA sequence of the amiloride-sensitive epithelial sodium channel (ENaC) in three patients who had low-renin hypertension with hypokalemia. The patients included a 24-year-old woman and her 20-year-old brother whose mother was hypertensive. The third patient was a 15-year-old girl with no family history of hypertension. METHODS: The DNA sequence of the ENaC was analyzed as follows. Venous blood samples were collected from the patients and total genomic DNA was prepared by standard methods. Specific primers were used for direct polymerase chain reaction; one set of primers for amplifying the C terminus (codon 523-638) of the , subunit of ENaC, and two sets of primers for amplifying the C terminus (codons 525-587 and 568-650) of the y subunit of ENaC. Polymerase chain reaction products were purified and subjected to direct DNA sequence analysis. RESULTS: Direct sequence analysis demonstrated the presence of a single-base substitution in one segment of the 0 subunit of ENaC, a C-T transition that changed the encoded Pro (CCC) at codon 616 to Ser (TCC) in the siblings (cases 1 and 2). In case 3, we found a missense mutation of Pro (CCC) to Leu (CTC) at codon 616. Case 3 is considered to be sporadic, since DNA sequencing of the PY motif of her parents gave normal results. CONCLUSIONS: The DNA sequences of the ENaC in three patients with Liddle's syndrome were analyzed. In one family case, we found a new missense mutation of Pro (CCC) to Ser (TCC) at codon 616 in the 0 subunit of ENaC. A genetic analysis of the amiloride-sensitive epithelial sodium channel is recommended in assessing patients with low-renin, salt-sensitive hypertension whose blood pressure is not responsive to spironolactone treatment. 相似文献
996.
Gallic acid (3,4,5-trihydroxybenzoic acid), a naturally occurring plant phenol, induces cell death in apparently different manners, depending on cell lines. Flow cytometric analysis and agarose gel electrophoresis indicated that internucleosomal breakdown of chromatin DNA was observed in HL-60RG cells but not in dRLh-84, HeLa, and PLC/PRF/5 cells, and that the action of gallic acid was independent of cell cycle. A detailed study of signal transduction revealed that the gallic acid-induced cell death of all cells tested in this study was prevented by treatment with the intracellular thiol antioxidant N-acetyl-L-cysteine, catalase, and the intracellular calcium chelator bis-(o-aminophenoxy)-N,N,N,N'-tetraacetic acid acetoxymethyl ester (BAPTA-AM). However, the effects of ascorbic acid, superoxide dismutase, EGTA, the endonuclease inhibitor zinc sulfate, the calmodulin inhibitor N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide (W-7), and the NADPH oxidase inhibitor diphenyleneiodonium chloride on cell death were different depending on the cell type, suggesting that the death signal induced by gallic acid was diverse among different cell types, although the production of reactive oxygen species, such as H2O2, and the elevation of intracellular calcium concentration were required as common signals. 相似文献
997.
998.
999.
1000.
K Kiyokawa Y Tai HY Tanabe Y Inoue T Yamauchi H Rikimaru K Mori T Nakashima 《Canadian Metallurgical Quarterly》1998,102(7):2336-2345
The present article describes a method that preserves circulation during the preparation of the pectoralis major myocutaneous flap used in head and neck reconstruction. The major disadvantage of this flap is its poor circulation and consequent partial necrosis. To solve this problem, we analyzed the circulation and hemodynamics of the pectoralis major myocutaneous flap (the perforator of the anterior intercostal branch located about 1 to 2 cm medial to the areola in the fourth intercostal space is important), evaluated the safe donor sites in the chest wall for a skin island (the perforator is included on the skin island's central axis), improved the surgical procedure for elevating flaps (for preventing perforator injuries), and devised a means to transfer flaps, thereby increasing the range of the flaps (the transfer route is under the clavicle). Using this technique, head and neck reconstruction was performed on 62 patients. The diagnosis included oral cancer (21), oropharyngeal carcinoma (10), parotid carcinoma (10), hypopharyngeal carcinoma (9), and other head and neck malignant tumors (12). Of these, partial or marginal necrosis of the flap caused by circulatory problems was detected in three patients (5 percent). Using our method, the problems associated with inadequate circulation in the pectoralis major myocutaneous flap were greatly alleviated, thus reconfirming the usefulness of this flap in head and neck reconstruction. 相似文献