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91.
He RH Fujita M Enoki M Hashimoto M Iikubo S Mo SK Yao H Adachi T Koike Y Hussain Z Shen ZX Yamada K 《Physical review letters》2011,107(12):127002
We demonstrated experimentally a direct way to probe a hidden propensity to the formation of a spin-density wave in a nonmagnetic metal with strong Fermi surface nesting. Substituting Fe for a tiny amount of Cu (1%) induced an incommensurate magnetic order below 20 K in heavily overdoped La(2-x)Sr(x)CuO(4). Elastic neutron scattering suggested that this order cannot be ascribed to the localized spins on Cu or doped Fe. Angle-resolved photoemission revealed a strong Fermi surface nesting inherent in the pristine La(2-x)Sr(x)CuO(4) that likely drives this order. Our finding presents the first example of the long-sought "itinerant-spin extreme" of cuprates, where the spins of itinerant doped holes define the magnetic ordering ground state; it complements the current picture of cuprate spin physics that highlights the predominant role of localized spins at lower dopings. 相似文献
92.
With an equiaffine immersion of codimension 1 into the affine space with the natural equiaffine structure, the conormal map is associated. In this paper, for an equiaffine immersion of general codimension into the space, we shall define the map corresponding to the conormal map, which is called the transversal volume element map. And we shall investigate if, an equiaffine immersion of general codimension into the space is determined by its affine fundamental form and its transversal volume element map. 相似文献
93.
Kazutoshi Koike 《代数通讯》2013,41(9):4303-4319
In this note, we use a universal algebraic argument to show that modules with 0-limits need not be equationally compact, thus providing a counter-example to an open problem of Jensen and Lenzing. 相似文献
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95.
While most other glasses exhibit non-exponential structural relaxation characteristics even when the change of fictive temperature is small, a high purity silica glass exhibited exponential structural relaxation. This was demonstrated by showing that the non-exponential exponent or β value of the KWW function of the high purity silica glass approaches unity when the change of the fictive temperature approaches zero both from higher and lower temperature sides of the heat-treatment temperature. The non-exponentiality of the structural relaxation of this glass when fictive temperature change is finite is due to the change of relaxation time during the structural relaxation. 相似文献
96.
D.C. Suministrado M. Koike T. Konaka S. Yuzawa I. Kuroishi 《Journal of Terramechanics》1990,27(4):307-320
Using mathematical models, approximate trajectories of soil furrow subslices were determined and the forces occurring on the moldboard surface were calculated. The various components of the normal force along the trajectory line of the middle section of the furrow slice were analysed in relation to the velocity of plowing operation and the curvature of the path. The soil reaction forces encountered by the share portion of the plow were also determined by a model which used the method of trial wedges to determine the angle of the failure surface with the horizontal. The sum of the calculated forces was compared with that obtained by actual plowing experiments performed in the laboratory. 相似文献
97.
98.
99.
In order to create a mathematical model of a soil-cutting blade, it is necessary to understand thoroughly the behavior of a soil slice and its interaction with the blade surface. The triaxial force transducer was developed to serve as one of the various tools to verify the proposed mathematical model. The prototype model transducer was fabricated, calibrated and tested with a soil slice on a flat cutting blade. The calibration results have indicated high sensitivity and the capability of simultaneous measurement in three directions. As a technological refinement, the detecting part of this triaxial force transducer was tapered to solve the problem of soil clogging in the opening clearance. Furthermore, the effects of the clearance configurations between the bore on the soil-cutting blade and the detecting part which is embedded in this bore were investigated to determine the most desirable configuration. The comparative results indicated that by tapering both the detecting part and the bore, the tangential stress measurement gained the highest value, and provided the most satisfactory condition for three-dimensional stress management. 相似文献
100.
Looking-glass synergistic pharmacological chaperones: DGJ and L-DGJ from the enantiomers of tagatose
Jenkinson SF Fleet GW Nash RJ Koike Y Adachi I Yoshihara A Morimoto K Izumori K Kato A 《Organic letters》2011,13(15):4064-4067
The enantiomers of tagatose are converted to L-DGJ [a noncompetitive inhibitor of human lysosome α-galactosidase A (α-Gal A), K(i) 38.5 μM] and DGJ [a competitive inhibitor of α-Gal A, K(i) 15.1 nM] in 66% yield. L-DGJ and DGJ provide the first examples of pharmacological chaperones that (a) are enantiomeric iminosugars and (b) have synergistic activity with implications for the treatment of lysosomal storage disorders and other protein deficiencies. 相似文献