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41.
Nanzai B Okitsu K Takenaka N Bandow H Tajima N Maeda Y 《Ultrasonics sonochemistry》2009,16(1):163-168
The influence of reaction vessel diameter on the sonochemical yield was investigated by using reaction vessels with five different diameters. It was revealed that the formation of H2O2 and chloride ion, from the sonolysis of pure water and 1,2,4-trichlorobenzene aqueous solution, was affected by the reaction vessel diameter. That is, these yields increased as the reaction vessel diameter increased up to ø 90 mm and then decreased over ø 90 mm. From the analyses of the measurement of sonochemiluminescence and the calorimetry, it was suggested that active cavitation bubbles were formed at certain zones. In the case of a larger diameter reaction vessel, it was suggested that bubble nuclei that have not grown up to the resonance size, escaped from the sonication zone to the non-sonication zone and dissolved away. As a result, the number of active cavitation bubbles and the yields of H2O2 and chloride ion would decrease in the case of a larger diameter reaction vessel. 相似文献
42.
Takashiro Akitsu Yasuaki Einaga 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(4):m183-m186
The crystal structures of the title compounds, [Cu(C15H11N2O2)2(C14H15N)2] and [Cu(C15H11N2O2)2(C14H15N)2]·2CHCl3, respectively, have been determined. The red disolvate complex affords a square‐planar CuN4 coordination environment in which the CuII atom lies on a centre of symmetry. The blue solvent‐free complex affords a distorted square‐pyramidal CuN4O coordination environment and adjacent molecules form centrosymmetric dimers. A comparison of the different crystal structures focuses on the role of the solvent molecules in supramolecular assemblies of the copper(II) complexes. 相似文献
43.
Takashiro Akitsu Yasuaki Einaga 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(4):m162-m164
The title compound, [Cu(C4H12N2)2(C3H6O)2](ClO4)2, is the first structurally characterized CuII complex having acetone as axial ligands. The complex adopts an elongated octahedral trans‐[CuN4O2] coordination geometry, with the Cu atom having 222 site symmetry. The axial Cu—O(acetone) and in‐plane Cu—N bond lengths are 2.507 (5) and 2.041 (3) Å, respectively. 相似文献
44.
Hiroaki Kitagishi Dr. Yasuaki Kakikura Hiroyasu Yamaguchi Dr. Koji Oohora Akira Harada Prof. Dr. Takashi Hayashi Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(7):1170-1170
Supramolecular protein polymers consisting of cytochrome b562 monomers with heme covalently attached to the protein surface are presented by T. Hayashi and co‐workers in their Communication on page 1271 ff. Not only one‐dimensional hemoprotein fibers with submicrometer lengths have been prepared, but when a heme triad was added as a pivot molecule, two‐dimensional protein assembly networks resulted, which cover over 100 square micrometers.
45.
The synergy between the electrical conductivity within the stacks of Ni(dmit)2 in the newly electrocrystallized [Fe(qsal)2][Ni(dmit)2]3.CH3CN.H2O and the spin conversion of Fe(qsal)2 is evidenced. In addition, the presence of a light-induced excited spin state trapping effect suggests that this complex is a prototypal photoswitchable spin-crossover molecular conductor. 相似文献
46.
Preechaworapun A Chuanuwatanakul S Einaga Y Grudpan K Motomizu S Chailapakul O 《Talanta》2006,68(5):1726-1731
Sulfonamides (SAs) were electrochemically investigated using cyclic voltammetry at a boron-doped diamond (BDD) electrode. Comparison experiments were carried out using a glassy carbon electrode. The BDD electrode provided well-resolved oxidation, irreversible cyclic voltammograms and higher current signals when compared to the glassy carbon electrode. Results obtained from using the BDD electrode in a flow injection system coupled with amperometric detection were illustrated. The optimum potential from a hydrodynamic voltammogram was found to be 1100 mV versus Ag/AgCl, which was chosen for the HPLC-amperometric system. Excellent results of linear range and detection limit were obtained. This method was also used for determination of sulfonamides in egg samples. The standard solutions of 5, 10, and 15 ppm were spiked in a real sample, and percentage of recoveries was found to be between 90.0 and 107.7. 相似文献
47.
Treetepvijit S Preechaworapun A Praphairaksit N Chuanuwatanakul S Einaga Y Chailapakul O 《Talanta》2006,68(4):1329-1335
The electrochemical analysis of tetracyclines was investigated using nickel-implanted boron-doped diamond thin film electrode (Ni-DIA) by cyclic voltammetry and high performance liquid chromatographic with amperometry. Cyclic voltammetry was used to study the electrochemical oxidation of tetracyclines. Comparison experiments were carried out utilizing as-deposited BDD and glassy carbon electrodes. Ni-DIA electrode provided well-resolved oxidative irreversible cyclic voltammograms and the highest current signals among the electrode studied. High performance liquid chromatography (HPLC) with amperometric detection was also studied. The chromatography was performed using a commercially available Inertsil C18 column, with the mobile phase being: 80% phosphate buffer (pH 2.5)-20% acetonitrile and detected at 1.55 V. The methods were validated over the concentration range 0.05-100 ppm with the overall average recoveries from 83.3 to 102.5% and R.S.D. of less than 10%. The proposed method was further applied to analyse shrimp samples. 相似文献
48.
Akihiko Okumura Yasuaki Takada Susumu Watanabe Hiroaki Hashimoto Naoya Ezawa Yasuo Seto Yasuo Takayama Ryoji Sekioka Shintaro Yamaguchi Shintaro Kishi Takafumi Satoh Tomohide Kondo Hisayuki Nagashima Tomoki Nagoya 《Journal of the American Society for Mass Spectrometry》2016,27(7):1219-1226
We propose detecting a fragment ion (Ph2As+) using counter-flow introduction atmospheric pressure chemical ionization ion trap mass spectrometry for sensitive air monitoring of chemical warfare vomiting agents diphenylchloroarsine (DA) and diphenylcyanoarsine (DC). The liquid sample containing of DA, DC, and bis(diphenylarsine)oxide (BDPAO) was heated in a dry air line, and the generated vapor was mixed into the humidified air flowing through the sampling line of a mass spectrometer. Humidity effect on the air monitoring was investigated by varying the humidity of the analyzed air sample. Evidence of the in-line conversion of DA and DC to diphenylarsine hydroxide (DPAH) and then BDPAO was obtained by comparing the chronograms of various ions from the beginning of heating. Multiple-stage mass spectrometry revealed that the protonated molecule (MH+) of DA, DC, DPAH, and BDPAO could produce Ph2As+ through their in-source fragmentation. Among the signals of the ions that were investigated, the Ph2As+ signal was the most intense and increased to reach a plateau with the increased air humidity, whereas the MH+ signal of DA decreased. It was suggested that DA and DC were converted in-line into BDPAO, which was a major source of Ph2As+. 相似文献
49.
Kazuki Matsumoto Jun Katsuyama Ryo Sugiyama Yasuaki Takizawa Seita Ishii Mitsuru Shinagawa Yuichi Kado 《Optical Review》2014,21(5):614-620
In this paper, we describe an induced signal measurement on the human body for developing a high-performance transceiver of an intra-body communication system. It is important to isolate awearable transceiver from an electrical instrument for precise measurement. We have developed a probe system using an optical isolation method including a laser diode, photo-diode, and optical fiber. The probe system can be successfully applied to the precise measurement of a receiving signal power at a wearable transceiver. We verify that the experimental results agree with the simulation results based on our previous channel model of intra-body communication. 相似文献
50.
With the aid of symbolic computation by Maple, a class of third-order nonlinear evolution equations admitting invariant subspaces generated by solutions of linear ordinary differential equations of order less than seven is analyzed. The presented equations are either solved exactly or reduced to finite-dimensional dynamical systems. A number of concrete examples admitting invariant subspaces generated by power, trigonometric and exponential functions are computed to illustrate the resulting theory. 相似文献