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124.
Keiji Nishioka 《manuscripta mathematica》1990,66(1):341-349
It is proved that a certain type of third order algebraic differential equations defined over ℂ which are satisfied by Schwarz
triangle functions, cannot be reduced to first order. 相似文献
125.
Hiroaki Yamamoto Youji Kanie Masakazu Arakawa Keiji Taniguchi 《Applied Physics A: Materials Science & Processing》1990,50(6):577-581
The transmission coefficient and the resonance condition in the one-dimensional rectangular double-, triple-, quadruple-, and quintuple-barrier structures are derived theoretically under the assumption of the constant tunneling effective mass. It is found that the resonance energies are different from the eigenvalues in the quantum well due to coupling between wells in the multiple-barrier (much more than triple-barrier) structures. It is confirmed that the transmission spectrum is a Lorentzian near to energies of resonance. 相似文献
126.
The relationship between contact pressure and sinkage must be represented by a mathematical model to estimate the sinkage and the motion resistance due to a vehicle. In this study an approximate and simple pressure-sinkage model is proposed. This model takes into account the effect of the size of the penetration plate on soil response, and includes two soil values that can be obtained by a single plate penetration test. It is submitted that the sinkage and the motion resistance of a tracked vehicle can be estimated by means of the proposed model. 相似文献
127.
Versatile In Situ Generated N‐Boc‐Imines: Application to Phase‐Transfer‐Catalyzed Asymmetric Mannich‐Type Reactions
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Dr. Taichi Kano Ryohei Kobayashi Prof. Keiji Maruoka 《Angewandte Chemie (International ed. in English)》2015,54(29):8471-8474
The efficient construction of nitrogen‐containing organic compounds is a major challenge in chemical synthesis. Imines are one of the most important classes of electrophiles for this transformation. However, both the available imines and applicable nucleophiles for them are quite limited given the existing preparative methods. Described herein are imine precursors which generate reactive imines with a wide variety of substituents under mild basic conditions. This approach enables the construction of various nitrogen‐containing molecules which cannot be accessed by the traditional approach. The utility of the novel imine precursor was demonstrated in the asymmetric Mannich‐type reaction under phase‐transfer conditions. 相似文献
128.
Hiroshi Kimura Koichiro Aikawa Yuichi Masubuchi Jun-ichi Takimoto K. Koyama Keiji Minagawa 《Rheologica Acta》1998,37(1):54-60
The mechanism of the electrorheological (ER) effect in two types of liquid crystalline polymer (LCP)/dimethylsiloxane (DMS)
blends was investigated by rheological measurements and by structure observation under electric field and shear flow. The
results show that the phase structures of these immiscible blends can be categorized into slipping (low viscosity) and non-slipping
(high viscosity) states. In the non-slipping state, higher viscosity LCP domains connect the electrodes. In the slipping state,
on the other hand, LCP domains do not connect the electrodes and the shear is mainly confined in the lower viscosity DMS domains.
The ER effect (electrically induced viscosity increase) originates from the electrically induced slipping to non-slipping
transition. In one of the blends, the ER effect occurs only at high shear rate, since this blend is in non-slipping state
even under no field if the shear rate is low.
Received: 29 April 1997 Accepted: 3 November 1997 相似文献
129.
Koichiro DotaTadashi Shimizu Shoji HasegawaMasaaki Miyashita Keiji Tanino 《Tetrahedron letters》2011,52(8):910-912
An efficient method for constructing a 10-membered carbocycle with an oxygen bridge has been developed on the basis of a formal [6+4] cycloaddition reaction. Under the influence of EtAlCl2, a dicobalt hexacarbonyl acetylene complex possessing a benzoyloxy group and an allylsilane moiety reacted with furan to give a 11-oxabicyclo[6.2.1]undec-9-ene derivative. On treatment with iodine, the cycloadduct underwent decomplexation followed by rearrangement of the oxygen bridge to afford a 11-oxabicyclo[5.3.1]undeca-1,5-diene derivative. 相似文献
130.
Hirota K Hasegawa T Nakajima T Makino K Terada H 《Colloids and surfaces. B, Biointerfaces》2011,87(2):293-298
In this work we obtain the thermodynamic properties of mixed (1-stearoyl-2-oleoyl-sn-glycero-3-phosphocholine) PC and (1-stearoyl-2-oleoyl-sn-glycero-3-phospho-l-serine (sodium salt)) PS monolayers. Measurements of compressibility (isotherms, bulk modulus, and excess area per molecule) and surface potential show that the properties of monolayers at the air–water interface depend on the concentration of ions (Na+ and K+) and the proportion of PS in the mixture. The dependence on PS arises because the molecule is originally bound to a Na+ counterion; by increasing the concentration of ions the entropy changes, creating a favorable system for the bound counterions of PS to join the bulk, leaving a negatively charged molecule. This change leads to an increase in electrostatic repulsions which is reflected by the increase in area per molecule versus surface pressure and a higher surface potential. The results lead to the conclusion that this mixture of phospholipids follows a non ideal behavior and can help to understand the thermodynamic behavior of membranes made of binary mixtures of a zwitterionic and an anionic phospholipid with a bound counterion. 相似文献