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101.
Akira Wada Katsuaki Koshimura Masahito Niibe Hidetoshi Saitoh Kazuhiro Kanda Haruhiko Ito 《Journal of Non》2012,358(1):124-128
Amorphous carbon nitride (a-CNx) films were formed from the decomposition of BrCN in the electron cyclotron resonance plasmas of He, Ne, and Ar. The local structures of these films were investigated by the carbon-K near edge X-ray absorption fine structure. It was found that the density of C=C bond in the film prepared with Ar plasma was 7–9 times larger than that with He or Ne plasmas. The [N]/([C] + [N]) ratios of films were estimated from the X-ray photoelectron spectra as 0.34 ± 0.05, 0.35 ± 0.04, and 0.28 ± 0.05 for the He, Ne, and Ar plasmas, respectively. It was found that C atoms in the sp2-hybridized state were incorporated into the two-dimensional and/or one-dimensional conjugated structures composed of ? C=N? in the cases of the He and Ne plasmas and of ? C=C? in the case of the Ar plasma. The compositions and the local structures of films can be explained in terms of a model based on the cyclazine-like network structures. 相似文献
102.
Midori Kanda Ko Urushibara Soyoung Park Shinya Fujii Hyuma Masu Kosuke Katagiri Isao Azumaya Hiroyuki Kagechika Aya Tanatani 《Tetrahedron》2019,75(19):2771-2777
N,N′-Bis(ortho-substituted phenyl)squaramides afforded chiral crystals, in which squaramide molecules are arranged in one-handed helical networks, upon simple recrystallization. Three types of crystals with different helices were obtained, depending on the substituents or recrystallization solvent. Folded-type intermolecular hydrogen-bonding interactions of squaramides play a key role in forming the helical networks. 相似文献
103.
H. Sawamura K. Kanda R. Yamazaki K. Toyoda S. Urabe 《Applied physics. B, Lasers and optics》2008,93(2-3):381-388
Optimum conditions for sideband cooling of 40Ca+ are numerically analyzed and appropriate parameters are evaluated. The dependence of optimum parameters for sideband cooling on the realistic experimental conditions, such as laser linewidth or heating rate, is investigated. For experimental verification of the analysis, a single 40Ca+ is sideband-cooled using parameters based on the analysis, and the achieved average oscillation quantum numbers are evaluated. As a result, a good agreement between the experimental value and numerical analysis is obtained. 相似文献
104.
105.
Kha Tram Pushpinder Kanda Bruno J. Salena Shuangyan Huan Yingfu Li 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(47):13013-13016
Microbial pathogens pose serious threats to public health and safety, and results in millions of illnesses and deaths as well as huge economic losses annually. Laborious and expensive pathogen tests often represent a significant hindrance to implementing effective front‐line preventative care, particularly in resource‐limited regions. Thus, there is a significant need to develop low‐cost and easy‐to‐use methods for pathogen detection. Herein, we present a simple and inexpensive litmus test for bacterial detection. The method takes advantage of a bacteria‐specific RNA‐cleaving DNAzyme probe as the molecular recognition element and the ability of urease to hydrolyze urea and elevate the pH value of the test solution. By coupling urease to the DNAzyme on magnetic beads, the detection of bacteria is translated into a pH increase, which can be readily detected using a litmus dye or pH paper. The simplicity, low cost, and broad adaptability make this litmus test attractive for field applications, particularly in the developing world. 相似文献
106.
107.
The oxo-steroids corticosterone, testosterone and progresterone were converted with 5-N,N-dimethylaminonaphthalene- 1 -sulphonohydrazide (DNS-hydrazine) into DNS-hydrazones, which were separated by reversed-phase liquid chromatography and detected fluorimetrically. The anti and syn conformers of the hydrazones were recognized on a C18 column with eluents consisting of imidazole buffer (nitrate, pH 6.0) containing acetonitrile, methanol, acetone or dioxane, and thus two peaks were observed for each oxo-steroid derivative. On the other hand, a single peak was obtained when an eluent containing tetrahydrofuran was used, affording highly sensitive detection of oxo-steroids. A further improvement in the detection of oxo-steroids down to subpicomole level was achieved by adding a gel permeation chromatographic clean-up procedure to remove the excess reagent before the analysis by reversed-phase liquid chromatography. 相似文献
108.
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110.
H. Nakatsuji M. Hada K. Kanda T. Yonezawa 《International journal of quantum chemistry》1983,23(2):387-397
Accurate Hellmann–Feynman force method for the first and second derivatives of energy has been applied to the studies of the chemical reaction systems. We have studied (1) the electronic origins of the structure-reactivity correlations in the reactions CH3 + H → CH4 and CH3 + CH3 → C2H6 and (2) the geometries and force constants in the reaction intermediate and the transition state of the reactions F? + HF → [FHF]? → FH + F? and H? + CH4 → CH4 + H?, respectively. An intuitive simplicity of the underlying concepts of the first and second derivatives of the present approach is shown in the analysis. 相似文献