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431.
The half-life of 207Bi was obtained from the genetic relation between 207Po and 207Bi, and between 211At and 207Bi. The half-life was found to be 33.4 ± 0.8 y. The half-life of 207Po was determined to be 5.81 ± 0.04 h by following the decay of the characteristic γ-rays from 207Po. The half-life of 211 At was determined tobe 7.23 ± 0.02 h by following the decay of γ-rays and α-particles from 211At and 211Po. The half-lives determined in the present work for 207Po and 211At agree with the literature although the half-life of 207Bi differs considerably from the currently accepted value of 38 y. The branching ratio of 211 At decaying through EC and α-decay modes was determined together with the branching ratios of the three α-particles emitted from 211Po. 相似文献
432.
Ban T Ohwaki T Ohya Y Takahashi Y 《Angewandte Chemie (International ed. in English)》1999,38(22):3324-3326
Growth of oriented seed crystals on a substrate led to a completely oriented and continuous membrane of LTA-type zeolite. The seed crystals of cubic morphology were dip-coated onto a tilted substrate (see schematic diagram) with the zeolite channels normal to the surface. The substrate was hydrothermally treated in a reaction mixture containing the organic ligand 2,2-bis(hydroxymethyl)-2,2',2"-nitrilotriethanol, which lowers the degree of supersaturation of [Al(OH)(4)](-) ions and preferentially facilitates the intergrowth of the seed crystals. 相似文献
433.
Yasufumi Takahashi Yu Kobayashi Ziqian Wang Yoshikazu Ito Masato Ota Hiroki Ida Akichika Kumatani Keisuke Miyazawa Takeshi Fujita Hitoshi Shiku Yuri E. Korchev Yasumitsu Miyata Takeshi Fukuma Mingwei Chen Tomokazu Matsue 《Angewandte Chemie (International ed. in English)》2020,59(9):3601-3608
High‐resolution scanning electrochemical cell microscopy (SECCM) is used to image and quantitatively analyze the hydrogen evolution reaction (HER) catalytically active sites of 1H‐MoS2 nanosheets, MoS2, and WS2 heteronanosheets. Using a 20 nm radius nanopipette and hopping mode scanning, the resolution of SECCM was beyond the optical microscopy limit and visualized a small triangular MoS2 nanosheet with a side length of ca. 130 nm. The electrochemical cell provides local cyclic voltammograms with a nanoscale spatial resolution for visualizing HER active sites as electrochemical images. The HER activity difference of edge, terrace, and heterojunction of MoS2 and WS2 were revealed. The SECCM imaging directly visualized the relationship of HER activity and number of MoS2 nanosheet layers and unveiled the heterogeneous aging state of MoS2 nanosheets. SECCM can be used for improving local HER activities by producing sulfur vacancies using electrochemical reaction at the selected region. 相似文献
434.
In experiments of games, players frequently make choices which are regarded as irrational in game theory. In papers of Khrennikov
(Information Dynamics in Cognitive, Psychological and Anomalous Phenomena. Fundamental Theories of Physics, Kluwer Academic,
Norwell, 2004; Fuzzy Sets Syst. 155:4–17, 2005; Biosystems 84:225–241, 2006; Found. Phys. 35(10):1655–1693, 2005; in QP-PQ Quantum Probability and White Noise Analysis, vol. XXIV, pp. 105–117, 2009), it was pointed out that statistics collected in such the experiments have “quantum-like” properties, which can not be explained
in classical probability theory. In this paper, we design a simple quantum-like model describing a decision-making process
in a two-players game and try to explain a mechanism of the irrational behavior of players. Finally we discuss a mathematical
frame of non-Kolmogorovian system in terms of liftings (Accardi and Ohya, in Appl. Math. Optim. 39:33–59, 1999). 相似文献
435.
Saito T Fukushima T Yui Y Miyazaki S Nakamoto A Namera A Inokuchi S 《Analytical and bioanalytical chemistry》2011,400(1):25-31
We present a method based on monolitic spin column extraction and gas chromatography–mass spectrometry as an analytical method
for screening diquat (DQ), paraquat (PQ), and fenitrothion in serum and urine. This method is useful for clinical and forensic
toxicological analyses. Recovery of DQ, PQ, and fenitrothion from serum and urine, spiked at concentrations between 0.1, 2.5,
20, and 45 μg/ml, ranged from 51.3% to 106.1%. Relative standard deviation percentages were between 3.3% and 14.8%. Detection
and quantitation limits for serum and urine were 0.025 and 0.05 μg/ml, respectively, for DQ, 0.1 and 0.1 μg/ml, respectively,
for PQ, and 0.025 and 0.05 μg/ml, respectively, for fenitrothion. Therefore, these compounds can be detected and quantified
in the case of acute poisoning. 相似文献
436.
Yoshiaki Matsuo Yosohiro Sugie Kouta Sakamoto Tomokazu Fukutsuka 《Journal of Solid State Electrochemistry》2011,15(3):503-510
LiMn2O4 thin-film electrodes were prepared by the sol?Cgel method combined with oxygen-plasma irradiation. Oxygen plasma with a power of 10 or 90?W was irradiated to the precursor thin film prepared from lithium acetate, manganese acetate tetrahydrate and polyvinylpyrrolidone on a Pt plate, and then it was fired at 723 or 973?K. X-ray diffraction and Raman measurements indicated that oxygen-plasma irradiation was effective to increase the crystallinity of the resulting LiMn2O4. Atomic force microscope observation showed that the particle size of LiMn2O4 in the resulting thin-film electrode was decreased and homogeneous distribution of LiMn2O4 particles was achieved. Oxidation of the electrolyte at higher potentials was suppressed and capacity retention at 328?K was dramatically improved for the LiMn2O4 thin-film electrode obtained at 973?K. The improved electrochemical stability is ascribed to the elimination of organic materials from precursor by oxygen-plasma irradiation. 相似文献
437.
438.
Himeno H Miyajima K Yasuike T Mafuné F 《The journal of physical chemistry. A》2011,115(42):11479-11485
Titanium oxide clusters were formed in the gas phase by the laser ablation of a Ti rod in the presence of oxygen in a He gas. Not only stoichiometric but also nonstoichiometric titanium oxide clusters, Ti(n)O(2n+x)(+) (n = 1-22 and x = -1-3), were formed. The content of oxygen atoms depends strongly on a partial pressure of oxygen. Gold clusters, Au(m) (m = 1-4), were generated by the laser ablation, which were then deposited on Ti(n)O(2n+x) clusters. The formation of Au(m)Ti(n)O(2n+x)(+) follows electron transfer from Au(m) to Ti(n)O(2n+x)(+). The reactivity of Au(m)Ti(n)O(2n+x)(+) cluster ions with CO was examined for different m, n, and x by the mass spectrometry. It was found that Au(m) on Ti(n)O(2n-1)(+) are less reactive than those on the other Ti(n)O(2n+x)(+) (x = 0 and 1). In addition, the reactivity is highest when Au(m) (m = 1 and 3) is on the stoichiometric titanium oxide (x = 0), whereas the reactivity is also high when Au(2) is on the oxygen-rich titanium oxide (x = 1). The reactivity was found to relate to geometrical structures of Au(m)Ti(n)O(2n+x)(+), which were studied by density functional calculations. 相似文献
439.
Hitoshi Okubo Fei Feng Daisuke Nakano Tomokazu Hirata Masahiko Yamaguchi Tokuji Miyashita 《Tetrahedron》1999,55(52):116-14864
We previously reported that an optically active cyclic amide consisting of a helical chiral 1,12-dimethylbenzo[c]phenanthrene-5, 8-dicarboxylic acid forms a stable monolayer on the water surface, and that the monolayer can be transferred on a solid support giving optically active Langmuir-Blodgett (LB) films. In this study, several related amides were synthesized, and their monolayer behaviors were investigated with expectation to prepare optically active LB films possessing functional groups. The result indicates that the cyclic amide structure and cyclohexyl moiety are essential for the formation of stable monolayer on the water surface. N-Alkylation of the secondary amide does not seriously affect the formation of monolayer, and chiral LB films are obtained by N,N-bis(3-meroaptopropyl) derivative of the cyclic amide. 相似文献
440.
Novel type of monolayer and multilayer of normally aligned,π-conjugated system with no alkyl chain was realized consisting of oligo-acene molecules by Langmuir-Blodgett technique. 相似文献