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941.
Akira Satoh 《Molecular physics》2013,111(8):1042-1052
We have shown the basic equation of the orientational distribution function of prolate spheroidal haematite particles with rotational Brownian motion in a simple shear flow under an applied magnetic field. The equation has been solved numerically in order to investigate the influence of the spin Brownian motion on the orientational distribution, the negative magneto-rheological effect and the characteristics of magnetisation. With respect to the orientational distribution, the present results are in good agreement with those of the theory without that motion, which shows that the spin Brownian motion does not significantly influence the orientational distribution. In contrast, the influence of the spin Brownian motion appears more significantly in the negative viscosity: the negative viscosity effect decreases in comparison with that of the previous theory without the spin Brownian motion. Moreover, a more significant negative magneto-rheological effect is obtained for a larger particle aspect ratio. Since the magnetisation has a strong relationship with the orientation of the magnetic moment, the effect of the spin Brownian motion appears more significantly in this characteristic. 相似文献
942.
Yuta Matsuura Masanori Kaku Shoichi Kubodera 《Applied physics. B, Lasers and optics》2013,110(3):397-400
Continuous extreme ultraviolet (EUV) emission intensity from a laser-produced plasma in the wavelength between 40 and 200 nm for a copper–tungsten alloy target was observed to be 1.3 times higher than that for a tungsten target. Using the alloy target, low-opacity regions of one material were filled with high-opacity regions of another material. This opacity effect resulted in the increase of a calculated Rosseland mean opacity compared with either of the constituents, which may explain the increase of the EUV emission intensity. 相似文献
943.
Qian Duan Yutaka Miura Atsushi Narumi Xiande Shen Shin‐Ichiro Sato Toshifumi Satoh Toyoji Kakuchi 《Journal of polymer science. Part A, Polymer chemistry》2006,44(3):1117-1124
N–Isopropylacrylamide (NIPAM) was polymerized using 1‐pyrenyl 2‐chloropropionate (PyCP) as the initiator and CuCl/tris[2‐(dimethylamino)ethyl]amine (Me6TREN) as the catalyst system. The polymerizations were performed using the feed ratio of [NIPAM]0/[PyCP]0/[CuCl]0/[Me6TREN]0 = 50/1/1/1 in DMF/water of 13/2 at 20 °C to afford an end‐functionalized poly(N‐isopropylacrylamide) with the pyrenyl group (Py–PNIPAM). The characterization of the Py–PNIPAM using matrix‐assisted laser desorption ionization time‐of‐flight mass spectrometry provided the number–average molecular weight (Mn,MS). The lower critical solution temperature (LCST) for the liquid–solid phase transition was 21.7, 24.8, 26.5, and 29.3 °C for the Py–PNIPAMs with the Mn,MS's of 3000, 3400, 4200, and 5000, respectively; hence, the LCST was dramatically lowered with the decreasing Mn,MS. The aqueous Py–PNIPAM solution below the LCST was characterized using a static laser light scattering (SLS) measurement to determine its molar mass, Mw,SLS. The aqueous solutions of the Py–PNIPAMs with the Mn,MS's of 3000, 3400, 4200, and 5000 showed the Mw,SLS of 586,000, 386,000, 223,000, and 170,000, respectively. Thus, lowering the LCST for Py–PNIPAM should be attributable to the formation of the PNIPAM aggregates. The LCST of 21.7 °C for Py–PNIPAM with the Mn,MS of 3000 was effectively raised by adding β‐cyclodextrin (β‐CD) and reached the constant value of ~26 °C above the molar ratio of [β‐CD]/[Py–PNIPAM] = 2/1, suggesting that β‐CD formed an inclusion complex with pyrene in the chain‐end to disturb the formation of PNIPAM aggregates, thus raising the LCST. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1117–1124, 2006 相似文献
944.
945.
Kenzo KitayamaHiroyuki Ohno Yusuke IdeKeisuke Satoh Saori Murakami 《Journal of solid state chemistry》2002,166(2):285-291
Phase equilibrium in the system Gd-Mn-O has been established at 1100°C while varying the partial pressure of oxygen between 0 and 13.00 in −log (PO2/atm), and a phase diagram at 1100°C is presented as a Gd2O3-MnO-MnO2 system. Under the experimental conditions, Gd2O3, MnO, Mn3O4, GdMnO3, and GdMn2O5 phases are present at 1100°C, but Gd2MnO4, Mn2O3, and MnO2 are not stable in the system. The substantial difference from the previously studied La-Mn-O and Nd-Mn-O systems lies in the fact that the LnMn2O5-type phase is stable under the present experimental conditions. A wide range of nonstoichiometry has been found in the GdMnO3 phase coexisting with Gd2O3. X in GdMnO3+X ranges from −0.03 at log PO2=−9.47 to 0.05 at log PO2=0. Nonstoichiometry is represented by an equation, NO/NGdMnO3=3.00×10−4(log PO2)3+5.80×10−3(log PO2)2+3.52×10−2(log PO2)+0.0464, and the activities of components in solid solution are calculated from the equation. Similar to the case of LaMnO3, GdMnO3 seems to vary in composition between the Gd2O3-rich and Gd2O3-poor sides. Lattice constants of GdMnO3 produced under different oxygen partial pressures and those of GdMn2O5 prepared in air were determined, along with spacings and relative intensities of GdMn2O5. Standard Gibbs energies of reactions shown in the system were calculated and compared with previously reported values. 相似文献
946.
Norifusa Satoh Takeshi Watanabe Yoshinori Iketaki Takashige Omatsu Masaaki Fujii Kimihisa Yamamoto 《先进技术聚合物》2004,15(4):159-163
The phenylazomethine dendrimer (DPA) is associated with Rhodamine 6G in chloroform, which results in the chemical shift attributed to the aromatic protons of phenylazomethine being moved upfield in the 1H‐NMR spectrum by increasing the Rhodamine 6G. The shift is saturated at the ratio of 1 : 1. On the basis of the NMR analysis, the association constant K of phenylazomethine with Rhodamine 6G was determined to be 1.4 × 104 (l/mol) in CDCl3 at 20°C. The association is also confirmed by UV‐vis spectroscopy, in which the absorption around 450 and 527 nm changes during the addition of Rhodamine 6G. The fluorescence intensity of the 1 : 1 complex of Rhodamine 6G and DPA G4 is stronger than that of the solution dissolved only in Rhodamine 6G at greater than 1 mM though it is generally known that the intermolecular interaction quenches the dye fluorescence in a concentrated solution. The association of DPA G4 with Rhodamine 6G suppresses the quenching at higher concentrations. Homogenous nano‐dots were observed on mica by casting the DPA G4 complex with Rhodamine 6G, in which the height and average area were 1.5–3 nm and 1.6 × 103 nm2 (the standard deviation σ = 3.7 nm2), respectively. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
947.
948.
Nobukatsu Nemoto Hisamitsu Kameshima Yuta Okano Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2003,41(10):1521-1526
Novel π‐conjugating polymers based on dibenzothiophene were synthesized with a novel dibenzothiophene derivative, 2,8‐bis(4,4,5,5‐tetramethyl‐1,3,2‐dioxaborolan‐2‐yl)dibenzothiophene ( 1 ), prepared from dibenzothiophene. The Suzuki coupling polycondensation of 1 with 2,7‐dibromo‐9,9‐dioctylfluorene, 3,6‐dibromo‐9‐octylcarbazole, or 1,4‐dibromo‐2,5‐dioctyloxybenzene afforded the corresponding dibenzothiophene‐based polymers. The measurements of photoluminescence indicated that all these polymers exhibited blue emission in solution. The copolymer containing dibenzothiophene and 9,9‐dioctylfluorene units exhibited higher thermal stability than poly[(9,9‐dioctylfluorene‐2,7‐diyl)], although the quantum yield of copolymer was lower than that of poly[(9,9‐dioctylfluorene‐2,7‐diyl)]. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1521–1526, 2003 相似文献
949.
950.
Annals of Global Analysis and Geometry - Isothermic surfaces are surfaces which allow a conformal curvature line parametrisation. They form an integrable system, and Darboux transforms of... 相似文献