Synthesis and characterization of europium(II)-holoborates,Eu2B5O9Cl and Eu2B5O9Br

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), $\text{c}\text{=6.500(4)}\text{A}\text{?}$ and Z=4, and Eu₂B₅O₉Br in the orthorhombic system, C¹⁰_2v-Pnn2 or D¹²_2h-Pnnm, with cell dimensions: a=11.503(3), b=11.382(3), $\text{c}\text{=6.484(2)}\text{A}\text{?}$ 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.     

Preparation of polyacrylic dyes

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.     

Dietary supplement of isohumulones inhibits the formation of aberrant crypt foci with a concomitant decrease in prostaglandin E2 level in rat colon

Male Fischer 344 rats were subcutaneously injected with azoxymethane (AOM) twice weekly at a dose of 15 mg/kg and were fed with freeze-dried (FD) samples of beer brewed without hops (non-hops beer), beer with hops at 4 times the amount of regular lager beer (x 4-hops beer), and isomerized hop extract (IHE) for the whole experimental period (I/PI) or for the post-initiation period (PI) only. Feeding FD beer samples at a dose of 1% significantly decreased the number of aberrant cryp foci (ACF) in the PI protocol over five weeks.x4-hops beer showed stronger inhibitory effects on the development of the numbers of aberrant crypts per focus and large ACF with four or more crypts than non-hops beer. Feeding IHE to rats at a dose of 0.01% or 0.05% in either the I/PI or PI experiment significantly reduced the numbers of ACF. Prostaglandin E2 (PGE2) levels in colonic mucosa of AOM-treated rats were significantly reduced by feeding of IHE. PGE2 production induced by lipopolysaccharide/interferon-gamma (LPS/IFN-gamma) in RAW264.7 cells was also reduced by treatment with IHE and isohumulone in a dose-dependent manner. These observations suggest that isohumulones show chemopreventive effects on ACF formation in rat colon by inhibiting the production of PGE2.     

Development of a non-contact micro-liquid mixing method and application to chemical auto-analyzers

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.     

Theory of magnetically polarizable superconductors

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 X_f due to the polarizable medium and is greatly reduced as X_f 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.