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101.
102.
Summary Boric and germanic acids were detected by a conductivity detector after ion-exclusion Chromatographic separation on a cation-exchange resin. Neither acid could be directly measured by a conductivity detector because they were very weak. However, use of eluents of polyol compounds permitted their determination by a conductivity detector. With 0.1 M of fructose as eluent, it was possible to detect 0.5 ppb of boric acid (as B) and 1.5 ppb of germanic acid (as Ge).
HPLC-Bestimmung von Borsäure und Germaniumsäure mit konduktometrischer Detection
Zusammenfassung Beide Säuren wurden mit Hilfe eines Leitfähigkeitsdetektors nach Trennung durch Ionenausschluß-Chromatographie an einem Kationenaustauscher analysiert. Eine direkte Messung war wegen der Schwäche der Säuren nicht möglich; daher wurde eine Elution mit Polyolen durchgeführt. Mit 0,1 M Fructoselösung als Eluens konnten noch 0,5 ppb Borsäure (als B) und 1,5 ppb Germaniumsäure (als Ge) nachgewiesen werden.相似文献
103.
Ryoichi Suzuki Yoshinori Kobayashi Tomohisa Mikado Hideaki Ohgaki Mitsukuni Chiwaki Tetsuo Yamazaki 《Hyperfine Interactions》1994,84(1):345-353
A positron pulsing system for an intense positron beam generated by an electron linac is reported. The pulsing system generates an intense pulsed positron beam of variable energy and variable pulse period. The pulsed positron beam is used as a non-destructive probe for various material research. In this paper, we also discuss applications of the pulsed positron beam: positron lifetime spectroscopy, age-momentum correlation spectroscopy, positronium time-of-flight measurement, and positron annihilation-induced Auger electron spectroscopy with a time-of-flight technique. 相似文献
104.
105.
Tetsuo Hatsuda 《The European Physical Journal C - Particles and Fields》2005,43(1-4):45-49
Hadronic modes in the quark-gluon plasma and their spectral properties are discussed on the basis of the lattice QCD data analyzed by the maximum entropy method.Arrival of the final proofs: 25 March 2005PACS:
12.38.Mh, 12.38.Gc 相似文献
106.
Spontaneous Formation of Microgroove Arrays on the Surface of p‐Type Porous Silicon Induced by a Turing Instability in Electrochemical Dissolution 下载免费PDF全文
Prof. Dr. Kazuhiro Fukami Tomoko Urata Prof. Dr. Katharina Krischer Prof. Dr. Naoya Nishi Prof. Dr. Tetsuo Sakka Dr. Atsushi Kitada Prof. Dr. Kuniaki Murase 《Chemphyschem》2015,16(8):1613-1618
Self‐organization plays an imperative role in recent materials science. Highly tunable, periodic structures based on dynamic self‐organization at micrometer scales have proven difficult to design, but are desired for the further development of micropatterning. In the present study, we report a microgroove array that spontaneously forms on a p‐type silicon surface during its electrodissolution. Our detailed experimental results suggest that the instability can be classified as Turing instability. The characteristic scale of the Turing‐type pattern is small compared to self‐organized patterns caused by the Turing instabilities reported so far. The mechanism for the miniaturization of self‐organized patterns is strongly related to the semiconducting property of silicon electrodes as well as the dynamics of their surface chemistry. 相似文献
107.
Inside Cover: Spontaneous Formation of Microgroove Arrays on the Surface of p‐Type Porous Silicon Induced by a Turing Instability in Electrochemical Dissolution (ChemPhysChem 8/2015) 下载免费PDF全文
108.
Tetsuo Okada 《Chemical record (New York, N.Y.)》2017,17(4):415-428
Ice has a variety of scientifically interesting features, some of which have not been reasonably interpreted despite substantial efforts by researchers. Most chemical studies of ice have focused on the elucidation of its physicochemical nature and its roles in the natural environment. Ice often contains impurities, such as salts, and in such cases, a liquid phase coexists with solid ice over a wide temperature range. This impure ice also acts as a cryoreactor, governing the circulation of chemical species of environmental importance. Reactions and phenomena occurring in this liquid phase show features different from those seen in normal bulk aqueous solutions. In the present account, we discuss the chemical characteristics of the liquid phase that develops in a frozen aqueous phase and show how novel analytical systems can be designed based on he features of the liquid phase which are predictable in some cases but unpredictable in others. 相似文献
109.
Phase-separation and distribution of phenyl groups for PhTES-TEOS coatings prepared on polycarbonate substrate 总被引:1,自引:0,他引:1
Yutaka Mizuta Yusuke Daiko Atsushi Mineshige Masafumi Kobune Tetsuo Yazawa 《Journal of Sol-Gel Science and Technology》2011,58(1):80-84
Phenyltriethoxysilane (PhTES) and tetraethoxysilane (TEOS) coatings [xPhTES·(100 − x)TEOS (mol%)] (x = 0 − 80) were prepared on polycarbonate (PC) substrate, and adhesion, surface hardness and distribution of phenyl groups
were studied. The coatings with more than 60 mol% of PhTES showed good adhesion (≈ 100%), and the pencil hardness of PC substrate
(4B) improved to 2B or B after the coatings. Bulk gels with the same compositions were also prepared, and distribution of
phenyl groups were estimated using fourier transform infrared (FT-IR) spectroscopy (KBr method for bulk gels and attenuated
total reflection (ATR) method for coatings). A significant difference for the distribution of phenyl groups was clearly observed
between bulk gels and coatings, suggesting PC substrate affects the distribution of phenyl groups in coatings. The adhesion
and FTIR results revealed that there is an interaction caused by π-electrons between benzene rings on PC substrate and phenyl
groups of PhTES-TEOS coatings. It was found that the adhesion was strongly correlated with the phenylsilsesquioxane networks
formed around PC substrate side. 相似文献
110.
Shoji T Higashi J Ito S Okujima T Yasunami M Morita N 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(18):5116-5129
Ethynylated 2H-cyclohepta[b]furan-2-ones 5-15 have been prepared by Pd-catalyzed alkynylation of 3-iodo-5-isopropyl-2H-cyclohepta[b]furan-2-one (2) with the corresponding ethynylarenes or the reaction of 2-iodothiophene with 3-ethynyl-5-isopropyl-2H-cyclohepta[b]furan-2-one (4) under Sonogashira-Hagihara conditions. Compounds 5-15 reacted with tetracyanoethylene in a formal [2+2] cycloaddition reaction, followed by ring opening of the initially formed [2+2] cycloadducts, cyclobutenes, to afford the corresponding 1,1,4,4-tetracyanobutadienyl (TCBD) chromophores 16-26 in excellent yields. The intramolecular charge-transfer interactions between the 2H-cyclohepta[b]furan-2-one ring and TCBD acceptor moiety were investigated by UV/Vis spectroscopy and theoretical calculations. The redox behavior of the novel TCBD derivatives 16-26 was examined by cyclic voltammetry and differential pulse voltammetry, which revealed multistep electrochemical reduction properties, depending on the number of TCBD units in the molecule. Moreover, a significant color change was observed by UV/Vis spectroscopy under electrochemical reduction conditions. 相似文献