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991.
Corrigendum: Electronic Transitions in Conformationally Controlled Tetrasilanes with a Wide Range of SiSiSiSi Dihedral Angles
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992.
Ono Kiminori Watanabe Aki Dewa Kazuki Matsukawa Yoshiya Saito Yasuhiro Matsushita Yohsuke Aoki Hideyuki Fukuda Okiteru Aoki Takayuki Yamaguchi Togo 《Journal of nanoparticle research》2014,16(7):1-11
Journal of Nanoparticle Research - Dextrans are widely used as additives in food, pharmaceutical, and cosmetics because of their hydrophilicity, biocompatibility, and low toxicity. These features... 相似文献
993.
994.
Rational Synthesis of Antiaromatic 5,15‐Dioxaporphyrin and Oxidation into β,β‐Linked Dimers
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Akihide Nishiyama Masaya Fukuda Dr. Shigeki Mori Prof. Dr. Ko Furukawa Dr. Heike Fliegl Prof. Dr. Hiroyuki Furuta Prof. Dr. Soji Shimizu 《Angewandte Chemie (International ed. in English)》2018,57(31):9728-9733
5,15‐Dioxaporphyrin was synthesized for the first time by a nucleophilic aromatic substitution reaction of a nickel bis(α,α′‐dibromodipyrrin) complex with benzaldoxime, followed by an intramolecular annulation of the α‐hydroxy‐substituted intermediate. This unprecedented molecule is a 20π‐electron antiaromatic system, in terms of Hückel's rule of aromaticity, because lone pair electrons of oxygen atoms are incorporated into the 18π‐electron conjugated system of the porphyrin. A theoretical analysis based on the gauge‐including magnetically induced current method confirmed its antiaromaticity and a dominant inner ring pathway for the ring current. The unique reactivity of 5,15‐dioxaporphyrin forming a β,β‐linked dimer upon oxidation was also revealed. 相似文献
995.
Wen-Jun Li Er-Wei Shi Jung-Min Ko Zhi-zhan Chen H. Ogino Tsuguo Fukuda 《Journal of Crystal Growth》2003,250(3-4):418-422
The MoS2 nanowires with diameters of 4 nm and lengths of 50 nm were synthesized by a hydrothermal method using 0.36 g MoO3 and 1.8 g Na2S as precursors in 0.4 mol/l HCl solution at 260°C. The products are characterized by XRD, XPS, TEM, HTEM and BET. Results show that the as-prepared MoS2 nanowires consist of 1–10 sulfide layers with BET surface areas of 107 m2/g. The possible reaction route and the formation mechanism of the MoS2 nanowires are discussed. The effects of exterior conditions such as pH value, temperature, concentration of precursors and additives on the particle size and morphology of MoS2 crystallites were investigated. 相似文献
996.
Junyong Kang Yasunori Okano Keigo Hoshikawa Tsuguo Fukuda 《Journal of Crystal Growth》1994,140(3-4):435-438
A vertical gradient freeze apparatus was set up to investigate the influence of a vertical magnetc field on Te dopant segregation in InSb. Te-doped InSb crystals were grown in the presence and absence of an 80.0 kG magnetic field. The axial profile of the Te concentration in the crystal grown in the magnetic field was observed to be more uniform than that grown without magnetic field, which was attributed to the influence of the high magnetic field on Te dopant segregation by reducing convection in the melt. 相似文献
997.
A. Yoshikawa T. Satonaga K. Kamada H. Sato M. Nikl N. Solovieva T. Fukuda 《Journal of Crystal Growth》2004,270(3-4):427-432
Micro-pulling-down (μ-PD) growth apparatus was modified for fluoride crystals. PrF3 was grown with various concentrations of Ce3+ from 0–100%. The crystals were transparent and colorless (CeF3) or greenish and 3 mm in diameter and 15–50 mm in length. Neither visible inclusions nor cracks were observed. Radioluminescence spectra and decay kinetics were measured for the sample set at room temperature. In comparison to the Czochralski or Bridgman method, the μ-PD method allows to produce single crystalline material in a faster thus more economic way. Once it is established for the fluoride crystals, it is an efficient tool for exploring the field of new functional fluorides. 相似文献
998.
Azuma Godai Fukuda Mituhiro Kim Sunyoung Yamashita Makoto 《Journal of Global Optimization》2022,82(2):243-262
Journal of Global Optimization - We study the exactness of the semidefinite programming (SDP) relaxation of quadratically constrained quadratic programs (QCQPs). With the aggregate sparsity matrix... 相似文献
999.
1000.
Transient heat transfer coefficients for helium gas flowing over a horizontal plate (ribbon) were measured under wide experimental conditions. The platinum plate with a thickness of 0.1 mm was used as the test heater and heated by electric current. The heat generation rate was exponentially increased with a function of Q0 exp(t/τ). The gas flow velocities ranged from 4 to 10 m/s, the gas temperatures ranged from 290 to 353 K, and the periods of heat generation rate, τ, ranged from 50 ms to 17 s. The surface superheat and heat flux increase exponentially as the heat generation rate increases with the exponential function. It was clarified that the heat transfer coefficient approaches the quasi-steady-state one for the period τ longer than about 1 s, and it becomes higher for the period shorter than around 1 s. Empirical correlation for transient heat transfer was also obtained based on the experimental data. 相似文献