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Europium(II)-haloborates, Eu2B5O9Cl and Eu2B5O9Br, were synthesized and characterized by X-ray analysis, magnetic susceptibility and luminescent spectral measurements. The chloroborate Eu2B5O9Cl crystallizes in the tetragonal system, D64-P42212, with cell dimensions: a=11.349(4), and Z=4, and Eu2B5O9Br in the orthorhombic system, C102v-Pnn2 or D122h-Pnnm, with cell dimensions: a=11.503(3), b=11.382(3), and Z=4. Both of them were paramagnets with paramagnetic Curie temperature at about ?1 K, and band emissions peaking at about 430 and 435 nm which were based on a 4f7-4f65d transition of Eu2+ ion were observed on Eu2B5O9Cl and Eu2B5O9Br, respectively. 相似文献
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Polyacrylic chloride was reacted with aminonaphthol sulfonic acid to give a polymeric intermediate, from which the corresponding dyestuff was prepared by coupling with an aromatic diazonium salt. The water-solubility of the polymeric azo dye was found to depend mainly on the number of sulfonic groups in the molecular chain, and the colouring of dye was comparatively rich in variety. A copolymer of acrylic chloride with methyl methacrylate was directly reacted with a dyestuff containing amino groups to give a polymeric dye. In the molecular chain of those polymeric dyes, the functional structure of the dyestuff was kept by its incorporation to the acrylic polymer chain. 相似文献
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A new mixing method, which can mix some hundred microliters of liquid in a vessel without any physical contact, was developed. This mixing method used free surface waves in a vessel generated by ultrasound irradiation from outside the vessel. First, feasibility of circulation flow induced by waves was discussed with a numerical simulation. The mixing mechanism was then experimentally verified by flow visualization using a dye. Next, the method was applied to mixing serums and reagents. The serum-reagent mixture was visualized by using the Schlieren method, and the mixing performance was quantified from the visualized images. The experimental results show that the new mixing method is suitable for volumes of serum-reagent mixtures ranging up to . Finally, by implementing the new mixing method in a standard chemical auto-analyzer, a new kind of chemical auto-analyzer that does not suffer cross-contamination between samples was produced. 相似文献
128.
Kazushige Machida 《Journal of Low Temperature Physics》1983,53(3-4):405-417
Superconductors containing a magnetically polarizable medium under an applied magnetic field are discussed theoretically. It is shown that instead of the Pauli limiting field found by Chandrasekhar and Clogston for nonmagnetic superconductors, the maximum critical field is limited by the effect of the susceptibility Xf due to the polarizable medium and is greatly reduced as Xf increases, indicating the appearance of the first-order phase transition from the superconducting to the normal state. The magnetic behavior of the ferromagnet superconductor ErRh4B4 under applied fields is analyzed in terms of this idea. 相似文献
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130.
Heishiciro Takahama Hitoshi Kawamura Seizo Kato Hajime Yokosawa 《International Journal of Engineering Science》1979,17(6):735-744
Energy separation performance of a steam-operated vortex tube is experimentally investigated, and some reasonable criteria and expressions to estimate the energy separation performance are also introduced. The performance characteristics defined by the above expressions are the same as those of ideal gas in the high superheated region, and are well expressed independently of the degree of superheat, total mass flow rate and discharge resistance. When steam is in the wet region at the nozzle outlet, the performance considerably decreases because of the energy waste from moisture vaporization. And no energy is separated when the dryness fraction is less than approximately 0.98. Some technical data including the optimum operating conditions are also offered. 相似文献