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101.
M. Taniguchi S. Suga S. Shin K. Inoue M. Seki H. Kanzaki H. Nakashima Y. Shiraki 《Solid State Communications》1982,44(7):1079-1082
Core-exciton spectra of AlxGa1?xAs have been measured in the photon-energy region from 19 to 27 eV by use of synchrotron radiation. The core-excitons associated with the Ga 3d core-hole and the conduction electron around the lowest L6 and X6 symmetry points are found to be coupled with each other through intervalley electron-hole interactions. Quantitative analyses have elucidated that intervalley Coulomb term is playing a dominant role for this coupling. Another higher energy doublet structure is interpreted as due to the transition from the Ga 3d core-levels to the rather flat region in the second lowest conduction band around the L6 and L4, 5 symmetry points. 相似文献
102.
103.
Takasuke Matsuo Yoshio Kume Hiroshi Suga SyûzÔ Seki 《Journal of Physics and Chemistry of Solids》1976,37(5):499-506
The heat capacities of copper(II) formate tetrahydrate and tetradeuterate have been measured from 12 to 300 K with an adiabatic calorimeter. They have sigmoidal temperature dependence except near the antiferroelectric-paraelectric transition temperatures, 235.78 ± 0.05 K and 245.64 ± 0.05 K, respectively. The corresponding enthalpy changes are 836.0 ± 1.0 J mol?1 and 936.9 ± 0.5 J mor?1. The entropy changes are 3.546 ± 0.005 JK?1mol?1 and 3.814 ± 0.002 JK?1 mol?1. The heat capacities are larger in the high temperature phase than in the low temperature phase, the difference amounting to 5.74 JK?1 mol?1 and 7.15 JK?1 mol?1 for the hydrate and the deuterate, respectively. The heat capacity anomaly is compared with those in tin(II) chloride dihydrate and potassium hexacyanoferrate trihydrate and discussed in relation to the structure of the hydrogen bond networks in these substances. The discussion is extended to include possible properties of the hydrogen bond frameworks in ices Ih and II. 相似文献
104.
Summary A combined cation-exchange separation — atomic absorption spectrophotometric method is described for the determination of cobalt in silicate rocks. Silicate is decomposed with a mixture of perchloric acid — hydrofluoric acid. The residue is fed on a Bio-Rad AG 50W, X-8 resin (hydrogen form) column from 0.5 M hydrochloric acid — 0.05 M oxalic acid — 1.5% hydrogen peroxide solution. Polyvalent ions including ferric ions are not adsorbed on the column, while cobalt is retained together with alkaline earths and aluminium. Then, cobalt can be stripped selectively by elution with 1 M hydrochloric acid in 84% acetone solution and can subsequently be determined by AAS. The single column ion-exchange method described allows cobalt to be isolated from complicated matrices with good selectivity, sufficient enough to permit the final determination spectrophotometrically. Quantitative results are presented for the determination of cobalt in international rock standards and iron metal.
Genaue Bestimmung von Cobalt in silicatischen Gesteinen mit Hilfe einer Kombination von Kationenaustauschtrennung und Atomabsorptions-Spektralphotometrie
Zusammenfassung Bei dem beschriebenen kombinierten Verfahren wird die Probe mit Perchlorsäure/Flußsäure aufgeschlossen und der Rückstand in einer Lösung von 0,5 M Salzsäure, 0,05 M Oxalsäure und 1,5% Wasserstoffperoxid auf die Austauschersäule gegeben (Bio-Rad AG 50W, X-8, H-Form). Mehrwertige Ionen einschließlich Eisen werden nicht absorbiert, während Cobalt zusammen mit Erdalkalien und Aluminium zurückgehalten wird. Cobalt kann dann selektiv mit 1 M Salzsäure in 84% Aceton eluiert und anschließend mit AAS bestimmt werden. Das beschriebene Verfahren gestattet die Abtrennung von Cobalt aus komplizierten Matrices mit für die AAS-Bestimmung ausreichender Selektivität. Belegwerte für internationale Standardgesteine und metallisches Eisen werden angegeben.相似文献
105.
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108.
Kazuki Aita Takashi Temma Yoichi Shimizu Yuji Kuge Koh-ichi Seki Hideo Saji 《Journal of fluorescence》2010,20(1):225-234
Fluorescent analysis has been widely used in biological, chemical and analytical research. A useful fluorescent labeling agent
should include NIR emission, a large Stoke’s shift, and good labeling ability without interfering with the pharmacological
profile of the labeled compound. Thus, we planned to develop an M-AMF-DOTA(Nd) derivative composed of an NIR fluorescent moiety
and a maleimide conjugating moiety as a new NIR fluorescent labeling agent which fulfills these requirements. M-AMF-DOTA(Nd)
was synthesized from 4-amino-fluorescein and was conjugated with an avidin molecule (Avidin-AMF-DOTA(Nd)) through Lys-side
chains by reaction with 2-iminothiolane. The fluorescent features of M-AMF-DOTA(Nd) and Avidin-AMF-DOTA(Nd) were comparatively
evaluated. A binding assay of Avidin-AMF-DOTA(Nd) with D-biotin and a tumor cell-uptake study were performed to estimate the
effects of conjugation on the biological and physicochemical features of the protein. M-AMF-DOTA(Nd) was obtained in 22% overall
yield. M-AMF-DOTA(Nd) had a typical NIR fluorescence from the Nd ion (880 nm and 900 nm from 488 nm excitation). Avidin-AMF-DOTA(Nd)
was easily synthesized and also had typical NIR fluorescence from the Nd ion without loss of fluorescent intensity. The binding
affinity of Avidin-AMF-DOTA(Nd) to D-biotin was equivalent to naive avidin. Avidin-AMF-DOTA(Nd) was taken up by tumor cells
in the same manner as avidin conjugated with fluorescein isothiocyanate, an established, widely used fluorescent avidin. Results
from this study indicate that M-AMF-DOTA(Nd) is a potential labeling agent for routine NIR fluorescent analysis. 相似文献
109.
Tomoya Ito Koji Suda Takuya Kumamoto Waka Nakanishi Toshiko Watanabe Tsutomu Ishikawa Hiroko Seki Masatoshi Kawahata Kentaro Yamaguchi Yasumitsu Ogura Kazuo T. Suzuki 《Molecular diversity》2010,14(1):131-145
The role of o-bisguanidinobenzenes (BGBs) as new Brønsted base ligands for arsenic and phosphoric acids was examined. In solution state, complexation was evaluated by Job’s plot in 1H NMR experiment, indicating a 1:1 complex formation, whereas in solid state crystalline structures of complexes obtained were addressed by X-ray crystallographic analysis and/or solid state 13C NMR experiment, in which 1:2 complexes between the BGB and the acid components were normally formed. Based on these results, Merrifield and Hypogel® resin-anchored BGBs were designed and prepared as the corresponding polymer-supported host ligands. Evaluation of their coordination ability with metal salts (ZnCl2 and CoCl2) and arsenic acid in aqueous media by ICP-MS showed that the latter Hypogel® resin-anchored BGBs acted as effective immobilized base ligands. 相似文献
110.
Seki S Kobayashi Y Miyashiro H Ohno Y Usami A Mita Y Kihira N Watanabe M Terada N 《The journal of physical chemistry. B》2006,110(21):10228-10230
Highly reversible, safe lithium secondary batteries that use imidazolium-cation-based room-temperature ionic liquid as an electrolyte and lithium metal as an anode material were realized by the molecular design. To achieve higher reduction stability, an electron-donating substituent was introduced to promote charge delocalization in the imidazolium cation of room-temperature ionic liquids. 相似文献