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81.
Toishiyuki Uryu Haruki Ohkawa Ryuichi Oshima 《Journal of Polymer Science.Polymer Physics》1988,26(6):1227-1236
(N-Ethylcarbazol-3-yl)methyl acrylate and methacrylate were polymerized anionically and radically. Anionically-polymerized polyacrylate using ethylmagnesium chloride-benzalacetophenone as catalyst is an isotactic rich polymer with 85% isotactic dyad. All polymers except anionically polymerized polymethacrylate showed good film forming property. Hole drift mobilities measured by the time-of-flight method at room temperature and at 5 × 105 V/cm are in the following order: isotactic polyacrylate (1.0 × 10-5 cm2/V s) > atactic polyacrylate (1.8 × 10-6 cm2/V s) > atactic polymethacrylate (1.2 × 10-6 cm2/V s) at 5 × 105 V/cm. These results are discussed in terms of the hopping model between localized sites. 相似文献
82.
83.
Kanehiro Nakamura Ryuichi Endo Masatami Takeda 《Journal of Polymer Science.Polymer Physics》1976,14(7):1287-1295
Hydrophobic–hydrophilic block copolymers were prepared by “living” anionic polymerization. They consist of polystyrene and poly(ethylene oxide) blocks, and are soluble in water. Their interfacial properties were investigated, employing aqueous solutions. The block copolymers lowered the surface tension of water in analogy with the low molecular weight surfactants such as sodium lauryl sulfate and heptaethylene oxide n-dodecyl ether. Their aqueous solutions exhibited solubilization properties differing from those of polyethylene glycol. Therefore, it is thought that the polystyrene blocks produce solubilization phenomena. In samples of the same styrene content, the precipitation temperature of a high molecular weight copolymer in water was lower than that of a low molecular weight copolymer at the same concentration in the same solvent. The surface tension and precipitation temperature of aqueous solutions seem to be influenced by molecular weight and composition. 相似文献
84.
Yasuhiro Sanada Tatsuo Akiyama Yusuke Ujihira Eiji Niki 《Fresenius' Journal of Analytical Chemistry》1982,312(6):526-529
Summary Sodium ion-selective electrodes (Na+-ISE) were prepared by implanting Si+ and Li+ into alumina wafers and their characteristics were investigated. The alumina wafer had a thickness of 100 m and a diameter of 1.40 cm. The ionselective membrane was produced by ion-implanting of Li+ and Si+ on both sides of a single-crystal alumina wafer. The total doses of Li+ and Si+ were controlled to be the same, viz. 1013–1015 ions/cm2. The ion-implanted alumina wafer with 1014 or 4×1014 ions/cm2 of Li+ and Si+ showed better characteristics than the others.The response curves of the 1014 ions/cm2 implanted alumina wafer had a slope of 42 mV/pNa in a concentration range from 1–10–4mol/l. The full response achieved after about 1 min was reproducible. The proposed idea of producing Na+-ISE by ion-implantation technique was applied to functuate the gate surface of the field effect transitor to sodium ion. The sodium ion-sensitive FET (Na+-ISFET) prepared by implanting Li+ and Al+ at a dose of 5×1014 ions/cm2 showed a slope of 30 mV/pNa in a concentration range from 1–10–4mol/l.
Herstellung Na+-ionenselektiver Elektroden durch Einbau von Lithium und Silicium in Einkristall-Alumniumoxidblättchen und Anwendung zur Erzeugung von ISFET
Zusammenfassung Na+-selektive Elektroden wurden durch Einbau von Si+ und Li+ in Aluminiumoxidblättchen hergestellt und ihre Charakteristiken untersucht. Die Blättchen hatten eine Dicke von 100 m und einen Durchmesser von 1,40 cm. Ebenso wurde die Membran für einen ISFET hergestellt. Die Gesamtmenge von Li+ und Si+ wurde auf 1013–1015 Ionen/cm2 eingestellt, wobei sich bei 1014 oder 4×1014 Ionen/cm2 die beste Charakteristik ergab.Die Responsekurven der mit 1014 Ionen/cm2 versehenen Aluminiumoxidplättchen hatten eine Neigung von 42 mV/pNa in einem Konzentrationsbereich von 1–10–4mol/l. Der nach 1 min erhaltene volle Response war reproduzierbar. Die vorgeschlagene Technik wurde zur Einstellung der Gate-Oberfläche des Feldeffekt-Transistors auf Natriumion benutzt. Der Na+-sensitive FET (Na+-ISFET), der durch Einbau von Li+ und Al+ mit 5×1014 Ionen/cm2 hergestellt wurde, zeigte eine Neigung der Signalkurve von 30 mV/pNa in einem Bereich von 1–10–4mol/l.相似文献
85.
86.
We have measured the nuclear susceptibility of 3He in Grafoil filled with pure liquid 3He over the pressure region between 0.6 and 31.38 bars and at temperatures down to 0.5 mK with a cw NMR method. The nuclear magnetization corresponding to the adsorbed 3He layers on the Grafoil surface shows a strong ferromagnetic tendency with a periodic behavior as a function of liquid pressure. This observation is attributable to the growth of third and fourth solid 3He layers with the liquid pressure increase. The pressure dependence of the Weiss temperature indicates the third layer is completed at 19 bars and the fourth probably at 28 bars. The number of localized spins estimated from the solid magnetization is almost doubled from 0 to 28 bars, being consistent with this scenario. 相似文献
87.
Direct demagnetization has been made for two-dimensional solid 3He in both the paramagnetic and the antiferromagnetic phases. The lowest temperature is about 10 microK, judging from the observed magnetization for the paramagnetic solid 3He. The magnetization of the antiferromagnetic solid 3He shows a gradual increase to about 10 microK for the 4/7 phase adsorbed on both one layer of 4He and two layers of HD preplated graphite. This strongly suggests that the triangular antiferromagnet with the higher order multiple exchange has a quantum spin liquid ground state with nearly zero or extremely small spin gap less than 10 microK. 相似文献
88.
Ito F Ikoma T Akiyama K Kobori Y Tero-Kubota S 《Journal of the American Chemical Society》2003,125(16):4722-4723
Magnetic field effects on the charge-transfer (CT) fluorescence of a 1,2,4,5-tetracyanobenzene-doped poly(N-vinylcarbazole) thin film were investigated to clarify the primary process in photoconductive organic amorphous solid. The CT fluorescence increased with increasing magnetic field until 10 mT, and then it showed the dip around 40-50 mT. The hyperfine coupling mechanism observed in the low field and the level-crossing mechanism observed around 46 mT clearly indicate that the spin-conservative stepwise hole hops take place in the films. The boundary distance determined from the simulation based on the stepwise hopping model almost agreed with the interionic separation estimated within the Onsager analysis. 相似文献
89.
Tetsuji Sugata Yoko Kan Yoshiteru Nagaregawa Tomofumi Miyamoto Ryuichi Higuchi 《Journal of carbohydrate chemistry》2013,32(6):917-925
Abstract The hematoside analog 1 [NeuGcα(2→3)Galβ(1→4)Glcβ(1→1)Cer], which contains a phytosphingosine as a sphingoid base and an α-hydroxyfatty acid, has been synthesized. Coupling of the methyl (methyl 5-benzyloxyacetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-2-thio-D-glycero-α- and -β-D-galacto-2-nonulopyranosid)onate 5, prepared from the corresponding 5-acetamido derivative 2, with a lactose derivative 6 afforded sialolactoside 7, which was converted to the corresponding trichloroacetimidate 10. Glycosylation of 10 with the ceramide tribenzoate 12 gave the protected hematoside analog 13, which was deprotected to the hematoside analog 1. 相似文献
90.
H. Nakahara K. Sueki W. Sato K. Akiyama 《Journal of Radioanalytical and Nuclear Chemistry》2000,243(1):169-179
Radiochemical techniques have been applied in various ways to the study of fullerenes and metallofullerenes for the past several years, and they have provided invaluable information pertaining to the stability, structures, and formation of the novel carbon material. This paper reviews those experimental results that have fully shown the usefulness and uniqueness of radionuclides demonstrated in the field of fullerene science. 相似文献