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701.
Graessley's entanglement theory of viscosity modified by a frictional viscosity parameter ηfric is applied to data on solutions of polystyrene in diethyl phthalate at various concentrations and different temperatures. All the data modified give a single master curve over the entire rates of shear, as obtained previously with polydimethyl-siloxanes of various molecular weights and their solutions of various concentrations. The zero-shear viscosity η0, the upper Newtonian viscosity η∞, and ηfric are compared. Three activation energies for flow are estimated from η0, η∞ and ηfric, and are compared. The result suggests that the flow behavior in the upper Newtonian region is much more dependent on ηfric than on the entanglement viscosity term ηent. The ratio of zero-shear entanglement viscosity ηent,0 to ηfric can be used as a measure of the non-Newtonian behavior of the present solutions. Non-Newtonian behavior of the investigated polymer solution becomes appreciable at about ηent,0/ηfric = 2.5. These results are in agreement with previous conclusions based on comparison between η0, η∞ and ηfric for polydimethyl-siloxanes and their solutions. 相似文献
702.
Y. Nojiri K. Matsuta T. Minamisono K. Sugimoto K. Takeyama H. Hamagaki S. Nagamiya K. Omata Y. Shida I. Tanihata T. Kobayashi S. Matsuki S. Shimoura J. R. Alonso G. Krebs T. J. M. Symons 《Hyperfine Interactions》1987,35(1-4):1019-1022
A new on-line isotope separator was constructed and used successfully for the study on short-lived isotopes at the Bevalac
at Lawrence Berkeley Laboratory. The isotopes were produced through projectile fragmentation processes of high energy heavy-ion
reactions. Various isotopes were rigidity-separated by use of a beam line and, finally, the desired single isotope was range
analyzed to stop in a catcher. A large number of β-emitting21F nuclei were successfully collected and the nuclear lifetime was determined by detecting β-rays. 相似文献
703.
Atsushi Okamoto Satoshi Honma Shunsuke Uemura Terumasa Ito 《Optics & Laser Technology》2007,39(4):881-884
This paper presents a new proposal for a mutually pumped phase conjugate mirror (MPPCM) using cross polarization. In the cross polarized MPPCM, two light beams, whose polarizations are orthogonal to each other, incident on a photorefractive crystal, causing photorefractive interaction to generate phase conjugate waves with an orthogonal polarization to an incident beam. The use of Ar+ laser and BaTiO3 crystal in an experiment for the cross polarized MPPCM found that diffraction efficiency for an extraordinary beam is about 20%. As opposed to a conventional parallel polarized MPPCM in which the use of a beam splitter is required to separate a diffraction beam, the cross polarized MPPCM can efficiently extract phase conjugate waves by means of a polarized beam splitter, demonstrating the advantage of substantially improved efficiency. 相似文献
704.
Ryoichi Nishimura Shunsuke Hayashi Masao Fukushima 《Computational Optimization and Applications》2013,55(1):21-47
In a real situation, optimization problems often involve uncertain parameters. Robust optimization is one of distribution-free methodologies based on worst-case analyses for handling such problems. In this paper, we first focus on a special class of uncertain linear programs (LPs). Applying the duality theory for nonconvex quadratic programs (QPs), we reformulate the robust counterpart as a semidefinite program (SDP) and show the equivalence property under mild assumptions. We also apply the same technique to the uncertain second-order cone programs (SOCPs) with “single” (not side-wise) ellipsoidal uncertainty. Then we derive similar results on the reformulation and the equivalence property. In the numerical experiments, we solve some test problems to demonstrate the efficiency of our reformulation approach. Especially, we compare our approach with another recent method based on Hildebrand’s Lorentz positivity. 相似文献
705.
Dongmei Zhou Yongnan Zheng K. Matsuta M. Mihara M. Fukuda D. Nishimura J. Komurasaki D. Ishikawa R. Matsumiya T. Nagatomo T. Izumikawa S. Takahashi H. Hirano T. Ohtsubo S. Momota Y. Nojiri A. Kitagawa M. Kanazawa M. Torikoshi S. Sato T. Minamisono J. R. Alonso G. F. Krebs T. J. M. Symons Daqing Yuan Yi Zuo Ping Fan T. Suzuki Xizhen Zhang Shengyun Zhu 《Hyperfine Interactions》2007,180(1-3):37-42
The magnetic moment of 28P (I π = 3?+?, T1/2 = 270.3 ms) in the ground state has been measured by the $\upbeta $ -nuclear magnetic resonance method for the first time. The measured magnetic moment of $\vert \upmu (^{28}$ P)∣ = 0.309(9) $\upmu _{{\rm N}}$ is well reproduced by the shell model value of +0.306 $\upmu _{{\rm N} }$ . The shell model calculation also yields a proton density distribution with a long tail. The present results provide a strong confirmation of the configuration of the 2s 1/2 proton which should lead to the proton halo. 相似文献
706.
Jia Hao Pang Bin Wang Kohei Watanabe Ryo Takita Shunsuke Chiba 《Helvetica chimica acta》2021,104(10):e2100120
A method for the synthesis of 1,3-diarylpropylamines through hydroalkylation of styrenes with benzylamines by potassium hydride has been developed. The protocol is initiated by solvothermal treatment of benzylamines with KH at 100 °C to generate deprotonated anionic species, which undergo selective C-alkylation with arylalkenes at 0 °C to ambient temperature to afford 1,3-diarylpropylamines as the major product. 相似文献
707.
Takatoshi Matsumoto Yoshio Kinoshita Yusuke Kasai Shunsuke Kuwahara Masataka Watanabe 《Tetrahedron》2007,63(3):615-624
(S)-2-Methoxy-2-(1-naphthyl)propionic acid (MαNP acid 1) is used for enantioseparation of many secondary alcohols and for determining the stereogenic centers. In the liquid state, based on the 1H NMR anisotropy effect and reported results, it was shown that the MαNP ester preferred a coplanar relation between the methyl and naphthyl groups and a synperiplanar relation between the Cα-OMe and CO groups. In the case of 1,2,3,4-tetrahydro-4-phenanthrenol, which is a secondary alcohol, the stereogenic center was determined by X-ray analysis. It was shown that MαNP ester adopted similar arrangements in the solid state. However, it was presumed that the strong repulsion between oxygen atoms may be disadvantageous in the solid state. Therefore, we carried out conformational analysis using the simplest MαNP methyl ester to clarify this unique relationship. From detailed results based on the energy surface determined using the RHF/STO-3G basis set, the synperiplanar positional relation was the most stable, and the calculated results agreed with many reported experimental results. At the same time, all conformational isomers of the MαNP methyl ester were used to clarify the internal conversion pathways. 相似文献
708.
709.
Sato S Sekine A Ohashi Y Ishitani O Blanco-Rodríguez AM Vlcek A Unno T Koike K 《Inorganic chemistry》2007,46(9):3531-3540
Excitation by high-energy light, such as that of 313 nm wavelength, induces a photochemical ligand substitution (PLS) reaction of fac-[Re(bpy)(CO)3Cl] (1a) to give the solvento complexes (OC-6-34)- and (OC-6-44)-[Re(bpy)(CO)2(MeCN)Cl] (2 and 3) in good yields. The disappearance quantum yield of 1a was 0.01+/-0.001 at 313 nm. The products were isolated, and X-ray crystallographic analysis was successfully performed for 2. Time-resolved IR measurements clearly indicated that the CO ligand dissociates with subpicosecond rates after excitation, leading to vibrationally hot photoproducts, which relax within 50-100 ps. Detailed studies of the reaction mechanism show that the PLS reaction of 1a does not proceed via the lowest vibrational level in the 3MLCT excited state. The PLS reaction gives 2 and (OC-6-24)-[Re(bpy)(CO)2(MeCN)Cl] (5) as primary products, and one of the products, 5, isomerizes to 3. This type of PLS reaction is more general, occurring in various fac-rhenium(I) diimine tricarbonyl complexes such as fac-[Re(X2bpy)(CO)3Cl] (X2bpy=4,4'-X2-bpy; X=MeO, NH2, CF3), fac-[Re(bpy)(CO)3(pyridine)]+, and fac-[Re(bpy)(CO)3(MeCN)]+. The stable photoproducts (OC-6-44)- and (OC-6-43)-[Re(bpy)(CO)2(MeCN)(pyridine)]+ and (OC-6-32)- and (OC-6-33)-[Re(bpy)(CO)2(MeCN)2]+ were isolated. The PLS reaction of rhenium tricarbonyl-diimine complexes is therefore applicable as a general synthetic method for novel dicarbonyls. 相似文献
710.
Shunsuke Yatabe 《Archive for Mathematical Logic》2007,46(3-4):281-287
In , a set theory with the comprehension principle within Łukasiewicz infinite-valued predicate logic, we prove that a statement
which can be interpreted as “there is an infinite descending sequence of initial segments of ω” is truth value 1 in any model of , and we prove an analogy of Hájek’s theorem with a very simple procedure.
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