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311.
Changsheng Ding Hongfei Lin Kazuhisa Sato Yoshifumi Tsutai Hiromichi Ohtaki Mabito Iguchi 《Journal of Dispersion Science and Technology》2013,34(2):241-245
Spray coating method is a cost-effective technique suitable for the preparation of uniform and large-area thin films. This article presents findings on the preparation of dense electrolyte thin films by spray coating method. Dense, crack-free Gd-doped CeO2 (GDC) thin films with a thickness of approximately 2 µm were successfully prepared on porous NiO-GDC substrates. The influence of the dispersion of GDC nanopowders in susupension on the microstructure of the thin films was investigated. Results show that agglomeration of GDC nanopowders in suspension resulted in a porous microstructure and a densely packed microstructure was obtained for the film prepared from a well-dispersed suspension. 相似文献
312.
Nishino MN Fujimoto M Phan TD Mukai T Saito Y Kuznetsova MM Rastätter L 《Physical review letters》2008,101(6):065003
Earth's magnetosphere is an obstacle to the supersonic solar wind and the bow shock is formed in the front side of it. In ordinary hydrodynamics, the flow decelerated at the shock is diverted around the obstacle symmetrically about the Earth-Sun line, which is indeed observed in the magnetosheath most of the time. Here we show a case under a very low-density solar wind in which duskward flow was observed in the dawnside magnetosheath. A Rankine-Hugoniot test shows that the magnetic effect is crucial for this "wrong flow" to appear. A full three-dimensional magnetohydrodynamics (MHD) simulation of the situation confirming this interpretation and earlier simulations is also performed. It is illustrated that in addition to the "wrong flow" feature, various peculiar characteristics appear in the global picture of the MHD flow interaction with the obstacle. 相似文献
313.
314.
The V(acac)3 (acac = acetylacetonato)/AlEt2Cl catalyst is known to promote the living polymerization of propylene at low temperature. In the present study, the catalyst was modified by contacting with α,ω-unconjugated diene compounds, and the resulting catalyst was applied to propylene polymerization. The polymer produced shows a bimodal molar mass distribution, where the molecular weight of the higher molecular weight portion is twice that of the lower molecular weight portion. By using the CO quenching technique, it was found that the polymer with the higher molecular weight has a telechelic structure. 相似文献
315.
Dr. Yoshifumi Hashikawa Shumpei Sadai Shu Okamoto Prof. Dr. Yasujiro Murata 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2023,135(2):e202215380
Though [60]fullerene is an achiral molecular nanocarbon with Ih symmetry, it could attain an inherent chirality depending upon a functionalization pattern. The conventional chiral induction of C60 relies mainly upon a multiple addition affording a mixture of achiral and chiral isomers while their chiral function would be largely offset by the existence of pseudo-mirror plane(s). These are major obstacles to proceed further study on fullerene chirality and yet leave its understanding elusive. Herein, we showcase a carbene-mediated synthesis of C1-symmetric chiral open [60]fullerenes showing an intense far-red to near-infrared absorption. The large dissymmetry factor of |gabs|=0.12 was achieved at λ=820 nm for circular dichroism in benzonitrile. This is, in general, unachievable by other small chiral organic molecules, demonstrating the potential usage of open [60]fullerenes as novel types of chiral chromophores. 相似文献
316.
To check the possibility of living polymerization with a biscyclopentadienyl metallocene, propylene polymerization was conducted by Cp2ZrMe2 at –78°C or Cp2HfMe2 at –50°C using B(C6F5)3 and AlOct3 as a cocatalyst. The polymer yield increased linearly with polymerization time. The polypropylene obtained showed narrow molecular weight distribution (Mw/Mn 1.04–1.15). In addition, the number-average molecular weight increased in proportion to the polymerization time. It was, thus, found that living polymerization of propylene proceeds with the catalyst systems at a very low temperature. Isospecific living polymerization of 1-hexene also proceeded with the rac-(et)Ind2ZrMe2 catalyst at –78°C. 相似文献
317.
Alberto F. Garrido-Castro Yuta Hioki Yoshifumi Kusumoto Kyohei Hayashi Jeremy Griffin Kaid C. Harper Yu Kawamata Phil S. Baran 《Angewandte Chemie (International ed. in English)》2023,62(42):e202309157
A mild, scalable (kg) metal-free electrochemical decarboxylation of alkyl carboxylic acids to olefins is disclosed. Numerous applications are presented wherein this transformation can simplify alkene synthesis and provide alternative synthetic access to valuable olefins from simple carboxylic acid feedstocks. This robust method relies on alternating polarity to maintain the quality of the electrode surface and local pH, providing a deeper understanding of the Hofer-Moest process with unprecedented chemoselectivity. 相似文献