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11.
Ferrimagnetic order in the mixed rare-earth iron garnet (Y1??? x Gd x )3Fe5O12 system has been reinvestigated to cover the temperature range 5.0 to 700?K. The magnetization versus temperature exhibits a systematic variation with changing concentration x. The ferric-ion exchange coupling is strong enough to determine the Curie temperature ≈559?K for all the values x. The compensation temperature at which the magnetization crosses zero (shows the minimum) demonstrates the applicability of the three-sublattice model. The magnetic moment at 5.0?K indicates reasonable agreement with the relation n B?=?|21x???5.0|μB for the (Y1??? x Gd x )3Fe5O12 system. The compensation temperature decreases with decreasing x from 1.0 and reaches zero near x?=?0.24. An enlargement of coercive force in the hysteresis loop for the low-field M-H curve is clearly seen in near the compensation temperature, indicating that a single domain is formed and the rotation of this single domain occurs without building up a multidomain structure.  相似文献   
12.
Spectroscopic analysis of imidation of alkyl aryl sulfides with N-2,2,2-trichloro-1,1-dimethylethyloxycarbonyl azide 2 in the presence of (OC)Ru(salen) complex 1 strongly suggests that an addition compound of the azide 2 to 1 is the active species for the imidation, while the addition compound undergoes the undesired intramolecular CH insertion onto the salen ligand of the complex in the absence of sulfide, directly or via the corresponding nitrene-ruthenium species.  相似文献   
13.
Fourteen commercially available particle-packed columns and a monolithic column for hydrophilic interaction liquid chromatography (HILIC) were characterized in terms of the degree of hydrophilicity, the selectivity for hydrophilic-hydrophobic substituents, the selectivity for the regio and configurational differences in hydrophilic substituents, the selectivity for molecular shapes, the evaluation of electrostatic interactions, and the evaluation of the acidic-basic nature of the stationary phases using nucleoside derivatives, phenyl glucoside derivatives, xanthine derivatives, sodium p-toluenesulfonate, and trimethylphenylammonium chloride as a set of samples. Principal component analysis based on the data of retention factors could separate three clusters of the HILIC phases. The column efficiency and the peak asymmetry factors were also discussed. These data on the selectivity for partial structural differences were summarized as radar-shaped diagrams. This method of column characterization is helpful to classify HILIC stationary phases on the basis of their chromatographic properties, and to choose better columns for targets to be separated. Judging from the retention factor for uridine, these HILIC columns could be separated into two groups: strongly retentive and weakly retentive stationary phases. Among the strongly retentive stationary phases, zwitterionic and amide functionalities were found to be the most selective on the basis of partial structural differences. The hydroxyethyl-type stationary phase showed the highest retention factor, but with low separation efficiency. Weakly retentive stationary phases generally showed lower selectivity for partial structural differences.  相似文献   
14.
The following hydrogen and oxygen concentration cells using the oxide protonic conductors, \textCaZ\textr0.98\textI\textn0.02\textO3 - d {\text{CaZ}}{{\text{r}}_{0.98}}{\text{I}}{{\text{n}}_{0.02}}{{\text{O}}_{3 - \delta }} and \textCaZ\textr0.9\textI\textn0.1\textO3 - d {\text{CaZ}}{{\text{r}}_{0.{9}}}{\text{I}}{{\text{n}}_{0.{1}}}{{\text{O}}_{{3} - \delta }} , as the solid electrolyte were constructed, and their polarization behavior was studied,
( \textreversible: - )\text Pt,\textH2 + \textH2\textO/\textCaZ\textr1 - y\textI\textny\textO3 - d( y = 0.02\text or 0.1 )/\textAr( + \textH2 + \textO2 ),\text Pt( + :\textirreversible ) \left( {{\text{reversible}}: - } \right){\text{ Pt}},{{\text{H}}_2}{ + }{{\text{H}}_2}{\text{O}}/{\text{CaZ}}{{\text{r}}_{1 - y}}{\text{I}}{{\text{n}}_y}{{\text{O}}_{3 - \delta }}\left( {y = 0.02{\text{ or }}0.1} \right)/{\text{Ar}}\left( { + {{\text{H}}_2} + {{\text{O}}_2}} \right),{\text{ Pt}}\left( { + :{\text{irreversible}}} \right)  相似文献   
15.
Yano  Midori  Itoh  Takayuki  Tanaka  Yuusuke  Matsuoka  Daisuke  Araki  Fumiaki 《显形杂志》2020,23(2):313-329
Journal of Visualization - Ocean data have been improved with the enhancement of observed values and the evolution of computational technologies. It has also been verified based on the...  相似文献   
16.
We consider a model that is an extension of Krugman’s core–periphery model to the case of a bounded closed domain included in a Euclidean space. We can describe the relation of the density of workers, the density of nominal wages, and the density of real wages by the system of nonlinear integral equations of the model. If we obtain a solution of the system under the condition that the density of workers is given, then the solution is called a short-run equilibrium. In this paper we prove that this model has a short-run equilibrium, and we obtain a sufficient condition for its uniqueness. Moreover we obtain upper and lower estimates for short-run equilibria, and we construct a useful iteration scheme to numerically obtain short-run equilibria.  相似文献   
17.
Optical Review - The optical characteristics of a subwavelength grating (SWG) were examined as a means of achieving ultraviolet (UV) polarization control based on the interaction between a light...  相似文献   
18.
Menaquinone is biosynthesized from chorismate via a new pathway involving 1,4-dihydroxy-6-naphthoate in Streptomyces and presumably in pathogenic bacteria Helicobacter and Campylobacter.  相似文献   
19.
Summary: The oxidative polymerization of N‐glucosylaniline was carried out using ammonium persulfate as the oxidant in phosphate buffer. The structure of the isolated polymer was determined by 1H NMR, 13C NMR, and UV‐vis spectroscopy to be the polyaniline having glucose residues attached to the general polyaniline unit. Participation of the ortho‐position of the aromatic ring in the polymerization was also confirmed by the analyses.

The oxidative polymerization of N‐glucosylaniline.  相似文献   

20.
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