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1.
A single-component conducting molecular crystal composed of paramagnetic copper complexes, [Cu(dmdt)2]0+, was prepared. The crystal has an unprecedented three-dimensionally packed molecular arrangement and exhibits a fairly high conductivity (1 S cm-1 at room temperature). The magnetic susceptibility measurements revealed that [Cu(dmdt)2]0+ molecule keeps most of S = 1/2 spin moments. The difference of the bond lengths between [Cu(dmdt)2]0+ and [Cu(dmdt)2]2- is consistent with the result of the molecular orbital calculation.  相似文献   
2.
A simple method for quantitating proteins in the spots on two-dimensional polyacrylamide gel electropherograms is described. The system consists in three steps: (1) O'Farrell's two-dimensional gel electrophoresis of the proteins to be analysed; (2) staining of the gels with Coomassie brilliant blue; and (3) determination of the area and integrated density of the stained spots by the Joyce Loebl Magiscan-1 image analysis system. The method can be used for the determination of proteins in the range 0.5-100 micrograms/cm2; the amount of protein involved in most spots detected by the staining method actually falls within this range. As the minimum spot diameter that can easily be handled by the method is about 2 mm, as much as 30 ng of protein in such a spot can be determined. The method can also be applied to autoradiograms.  相似文献   
3.
Hybrid systems consisting of the conducting layers of organic donor molecules and the magnetic layers of inorganic anions have been focused on as possible bifunctional materials, whose conducting properties can be tuned by controlling the magnetic state of the anion layers on an application of magnetic field. Here we report the magnetoresistance of the antiferromagnetic organic superconductor, kappa-(BETS)2FeBr4 [BETS = bis(ethylenedithio)tetraselenafulvalene], consisting of the two-dimensional superconducting layers of the BETS semications and the insulating layers of the FeBr4- anions. Due to the metamagnetic nature of the Fe3+ spin system, characteristic resistivity decrease was observed just below the antiferromagnetic superconductor-to-ferromagnetic metal transition at 1.6 T. Furthermore, an indication of the onsets of the magnetic-field-induced superconductivity was discovered around 12.5 T.  相似文献   
4.
Guest water molecules confined in channels of porous coordination polymer crystals [Ln(2)Cu(3)(IDA)(6)]·nH(2)O (Ln = La, Nd, Sm, Gd, Ho, Er; IDA = [NH(CH(2)COO)(2)](2-); n ≈ 9) exhibited large dielectric constants (ε) and antiferroelectric behaviors at high temperatures (e.g., ε(Sm) ≈ 1300 at 400 K). In addition, plots of the temperature dependence of ε showed broad peaks at ~170 K, below which ε became very small. These puzzling temperature dependences of ε are consistent with the results of molecular dynamics simulations, suggesting the "freezing of thermal motion" of water molecules at ~170 K.  相似文献   
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6.
Reversible formation of F+-centers was observed over platinum promoted sulfated zirconia in the presence and absence of hydrogen. The intensity of ESR signal of F+-centers was increased by treatment in He stream and it was decreased rapidly by supply of hydrogen in gas phase. This behavior seems to be related to proton spillover.  相似文献   
7.
In the crystals of the cation radical salts based on the organic donor BMDT-TTF, the charge separation is observed. This comes from (1) nonequivalency of the site potential and (2) the long range electron-electron interaction, which are related to the two-dimensional nature of the molecular arrangement. The effects of the charge separation on the elctronic structure are discussed.  相似文献   
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9.
Bis(2,4-diaryl-3-thienyl) disulfide was isolated in the thermal decomposition of 2,5-diaryl-1,4-dithiin. The formation of the rearranged product as well as the kinetic data suggest strongly the valence isomerization of 2,5-diaryl-1,4-dithiin in the course of the decomposition.  相似文献   
10.
The radionuclide 67Cu was produced via the 68Zn(p,2p)67Cu reaction by irradiating enriched 68Zn targets with 70 MeV proton beam. Copper-67 was chemically separated from the zinc target by ion-exchange chromatography using Chelex-100 chelating ion-exchange resin. Procedure for recovery of the enriched 68Zn was developed. The target recovery yield of this method was evaluated to be more than 97%.  相似文献   
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