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41.
Hiroyuki Sasaki Akinori Tanaka Tazumi Nagasawa Shoji Suzuki Toshiro Nagase 《Solid State Communications》2004,129(2):91-95
We have carried out an angle-resolved photoemission study for CoSi2 nanofilms grown on the Si(111)-7×7 substrates. The surface of CoSi2(111) nanofilm changes from the bulk-truncated surface to the surface with additional Si-bilayer by annealing at higher temperature above 825 K. The angle-resolved photoemission spectra of the CoSi2 nanofilm annealed at 853 K show the spectral features originated from the surface resonance state on the CoSi2 surface terminated by Si-bilayer. From the detailed photoemission study, we discuss the surface electronic structure in CoSi2(111) nanofilms grown on Si(111) substrates. 相似文献
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The potassium-selective PVC membrane electrodes based on naphtho-15-crown-5 have rapid, stable and Nernstian response in the range 10-1–10-5 M. The selectivity coefficient for potassium over sodium is 4 × 10-4. 相似文献
44.
The equilibrium geometry of disilyne is not linear, but is twisted. The potential surfaces of acetylene and disilyne have a critical internuclear distance between the central atoms, where the stable geometry changes from linear to twisted forms the R-dependence of the valence-shell electron energy causes the difference in the structure of the molecules. 相似文献
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47.
Susumu Nakashima Masakazu Yagi Michio Zenki Akinori Takahashi Kyoji Tôei 《Fresenius' Journal of Analytical Chemistry》1984,319(5):506-509
Summary Nitrate was determined in natural water samples by flow-injection spectrophotometry. It was reduced to nitrite with copperized cadmium and the nitrite thus produced reacted with p-aminoacetophenone and m-phenylenediamine. The limit of detection was about 1.5 g l–1 for sample injections of 650 l. The sampling rate was about 40 samples h–1 and the relative standard deviation was above 1% for 0.1–0.3 mg l–1 nitratenitrogen. Nitrite present in the sample was determined separately and subtracted.
Nitratbestimmung in natürlichen Wässern mit Hilfe der Fließinjektions-Analyse
Zusammenfassung Nitrat wird bei dieser Methode mit Hilfe einer Cu/Cd-Reduktionssäule zu Nitrit reduziert, das mit p-Aminoacetophenon und m-Phenylendiamin zur Reaktion gebracht wird. Die gebildete Verbindung wird spektral-photometrisch gemessen. Die Nachweisgrenze beträgt etwa 1,5 g/l bei injizierten Probevolumina von 650 l. Der Probendurchsatz beträgt 40/h. Die relative Standardabweichung liegt über 1% bei 0,1–0,3 mg/l Nitrat-Stickstoff. Vorhandenes Nitrit wird gesondert bestimmt und abgezogen.相似文献
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49.
Yoshikawa M Kawamura K Ejima A Aoki T Sakurai S Hayashi K Watanabe K 《Macromolecular bioscience》2006,6(3):210-215
Novel molecular recognition materials were prepared from water soluble proteins from thermophile G. thermodenitrificans DSM465 by an alternative molecular imprinting method. Water soluble proteins from G. thermodenitrificans DSM465 were converted into the molecularly imprinted materials by adopting 9-EA as a print molecule. The molecularly imprinted protein membranes recognized As in preference to Gs. The adsorption isotherms led to the conclusion that molecular recognition sites toward As were constructed by the presence of 9-EA during the membrane preparation process. The affinity constant between As and the molecular recognition site thus constructed was determined to be 1.75 x 10(5) mol(-1) dm(3). The results obtained in the present study suggest that water soluble proteins from G. thermodenitrificans DSM465 is one of environmentally-friendly 'green' polymers to be converted into molecular recognition materials by applying an alternative molecular imprinting method. 相似文献
50.
Hisashi Yoshida Akinori Okamoto Seigi Mizuno Hiroshi Tochihara 《Surface science》2010,604(5-6):535-540
Low-energy electron diffraction (LEED) have been used to determine the Cu(0 0 1)–c(4 × 4)-Sn structure formed at 300 K. It is demonstrated that a structural model suggested by scanning tunneling microscopy observations is correct: The model consists of one substitutional Sn atom and four Sn adatoms in the unit cell. Optimum parameters of the determined c(4 × 4) structure reveal that Sn adatoms laterally are displaced by 0.30 Å away from ideal fourfold-hollow sites along the 〈100〉 directions. It is proposed that such displacements of the Sn adatoms cause the formation of a network of octagonal rings on Cu(0 0 1). The substitutional Sn atom is located at each center of the octagonal rings. The formation conditions of the network are discussed. 相似文献