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521.
S. Arumugam M. Kanagaraj N. R. Tamil Selvan S. Esakki Muthu J. Prakash G. S. Thakur A. K. Ganguli H. Yoshino K. Murata K. Matsubayashi Y. Uwatoko 《固体物理学:研究快报》2012,6(5):220-222
The Effect of pressure on the superconducting transition temperature of Yb doped Ce0.6Yb0.4FeAsO0.9F0.1 has been investigated for the first time using resistivity and magnetization studies. Increase in chemical pressure by substitution of smaller Yb3+ ions in place of Ce3+ ions results in a significant enhancement of Tc from 38 K (Yb free) to 47 K (40% Yb). Enhancement in Tc with external pressure has been observed for this compound up to a maximum value of Tc = 48.7 K at 1 GPa, beyond which Tc starts decreasing monotonously. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
522.
In order to obtain a better understanding of thermal substituent effects in 1,2,4-triazole-3-one (TO), the thermal behavior
of 1,2,4-triazole, TO, as well as urazole and the decomposition mechanism of TO were investigated. Thermal substituent effects
were considered using thermogravimetry/differential thermal analysis, sealed cell differential scanning calorimetry, and molecular
orbital calculations. The onset temperature of 1,2,4-triazole was higher than that of TO and urazole. Analyses of evolved
decomposition gases were carried out using thermogravimetry–infrared spectroscopy and thermogravimetry–mass spectrometry.
The gases evolved from TO were determined as HNCO, HCN, N2, NH3, CO2, and N2O. 相似文献
523.
Hisahiro Hagiwara Tomomi Nakamura Naotaro Okunaka Takashi Hoshi Toshio Suzuki 《Helvetica chimica acta》2010,93(1):175-182
Thirteen‐ to eighteen‐membered lactones were synthesized by ring‐closing olefin‐metathesis reactions of bis‐olefins with heterogeneous Grubbs‐supported ionic‐liquid catalysts (SILCs), in which homogeneous Grubbs catalysts were confined in pores of alumina with the aid of an ionic liquid. The Grubbs‐SILCs exhibited higher catalytic performance than their homogeneous counterparts and could be repeatedly recovered by simple filtration and re‐used several times. 相似文献
524.
Kimura T Kimura F Yoshino M 《Langmuir : the ACS journal of surfaces and colloids》2006,22(8):3464-3466
The powder crystallites of L-alanine, selected for demonstration purposes, suspended in a photocurable resin were subjected to a frequency-modulated rotating magnetic field, and the achieved three-dimensional alignment was fixed by photopolymerization of the resin. The obtained sample exhibited the X-ray diffraction pattern that was comparable to the pattern of an equivalent actual original single crystal. This was achieved for the first time by the simultaneous alignment of the two magnetic axes, i.e., the easy and hard magnetization axes with respect to the space coordinates. A theoretical estimation indicates that a better alignment of the sample can be obtained if the sample preparation conditions are improved. 相似文献
525.
Ito T Watanabe J Takai M Konno T Iwasaki Y Ishihara K 《Colloids and surfaces. B, Biointerfaces》2006,50(1):55-60
We investigated the preparation of polymer nanoparticles covered with phosphorylcholine (PC) groups and the immobilization of proteins in order to observe dual mode bioreactions on the nanoparticles. For the surface modification on the nanoparticles, a water-soluble amphiphilic phospholipid polymer with PC groups as a hydrophilic moiety was synthesized. In this polymer, an active ester group, which can immobilize proteins, was introduced. Using the phospholipid polymer as a solubilizer, poly(L-lactic acid) nanoparticles were prepared from its methylene chloride solution in an aqueous medium by the solvent evaporation method. The diameter of the nanoparticles was ca. 200 nm and the surface was covered with the PC groups and active ester groups. Proteins could immobilize on the nanoparticles under mild conditions by the reaction between the active ester group and amino group in the proteins. Both an antibody and enzyme were immobilized on the nanoparticles and bioreactions such as the antigen/antibody reaction and enzymatic reaction were observed. When an antigen was added to the suspension of the nanoparticles, aggregation of the nanoparticles occurred and then they precipitated. Also, the enzymatic reaction proceeded well when the enzyme substrate was added to the suspension. Based on these results, we provided polymer nanoparticles functionalized with both the antibody and enzyme, and the dual mode bioreactions could occur. We concluded that the novel polymer nanoparticles could be used for nano-/micro-scaled diagnostic and medical treatment systems. 相似文献
526.
Yoshino H Toda N Kobata M Ukai K Oshima K Utimoto K Matsubara S 《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(3):721-726
Bis(iodozincio)methane, prepared from diiodomethane and zinc, reacts with an organic halide in the presence of a transition-metal catalyst to give an iodozinciomethylenated compound; this then reacts with another organic halide to form a C--C bond. The overall process connects two electrophiles with one carbon atom. Bis(iodozincio)ethane can also undergo this transformation, yielding a new stereogenic center. The asymmetric induction of this stereogenic center was investigated by using a chiral palladium catalyst. 相似文献
527.
528.
529.
Yoshino H 《The Journal of chemical physics》2012,136(21):214108
We present a first principle scheme to compute the rigidity, i.e., the shear-modulus of structural glasses at finite temperatures using the cloned liquid theory, which combines the replica theory and the liquid theory. With the aid of the replica method which enables disentanglement of thermal fluctuations in liquids into intra-state and inter-state fluctuations, we extract the rigidity of metastable amorphous solid states in the supercooled liquid and glass phases. The result can be understood intuitively without replicas. As a test case, we apply the scheme to the supercooled and glassy state of a binary mixture of soft-spheres. The result compares well with the shear-modulus obtained by a previous molecular dynamic simulation. The rigidity of metastable states is significantly reduced with respect to the instantaneous rigidity, namely, the Born term, due to non-affine responses caused by displacements of particles inside cages at all temperatures down to T = 0. It becomes nearly independent of temperature below the Kauzmann temperature T(K). At higher temperatures in the supercooled liquid state, the non-affine correction to the rigidity becomes stronger suggesting melting of the metastable solid state. Inter-state part of the static response implies jerky, intermittent stress-strain curves with static analogue of yielding at mesoscopic scales. 相似文献
530.
Let R be a commutative Noetherian ring. We introduce the notion of colocalization functors with supports in arbitrary subsets W of Spec R. If W is a specialization-closed subset, then coincides with the right derived functor of the section functor with support in W. We prove that the local duality theorem and the vanishing theorem of Grothendieck type hold for with W being an arbitrary subset. 相似文献