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31.
J. Kuriplach L. Lešták M. Rotter B. Sedlák M. Trhlík M. Finger T. Lešner J. Dupák P. Novák M. Vobecký 《Hyperfine Interactions》1987,34(1-4):339-342
First experimental results of160Tb nuclear orientation in yttrium single crystal matrix are described. The influence of external magnetic field in combination with the crystal field interaction is discussed. 相似文献
32.
M. Rotter B. Sedlák J. Englich P. Čížek M. Finger P. Malinský 《Czechoslovak Journal of Physics》1986,36(11):1331-1335
The results of NMR/ON measurements on56,57,60Co isotopes in iron are presented in the paper. To avoid the uncertainties caused by local demagnetizing field inhomogeneities the measurements on two cobalt isotopes in one sample have been carried out. The values of nuclear-factors ratios
57/
60=1·805(20),
60/
56 = 0·761(20),
56/
57 = 0·726(20) and hyperfme anomalies56
60 = –0·036(10),60
57 = 0·017(10) and57
56 = 0·018(10) have been calculated from the experimental results.Dedicated to the 30th anniversary of the Joint Institute for Nuclear Research. 相似文献
33.
34.
35.
51V quadrupolar central transition NMR spectra of buffered (pH 7.6-8.0) solutions of bovine apo-transferrin (Tf) and bovine prostatic acid phosphatase (Pp) treated with vanadate show normal features (chemical shifts between -515 and -542 ppm) corresponding to the complexation of VO2+ to the Tf binding site and the Pp active centre, respectively. Addition of H2O2 leads to the temporary formation of complexed VO(O2)+ (delta approximately -595). Vanadate-dependent bromoperoxidase from the alga Ascophyllum nodosum exhibits an unusually high shielding both for the native (delta = -931) and the peroxo form (delta = -1135) of the enzyme. A resonance at -471 ppm is traced back to an inactive form with oxovanadium(V) in a trigonal-bipyramidal array. 相似文献
36.
Bimetallic ruthenium-tin catalysts were prepared using the sol-gel method and the method of carrier impregnation. Two different
procedures were used for their reduction — reduction in hydrogen atmosphere under an increased temperature, and reduction
using an aqueous solution of sodium borohydride. Hydrogenation of 3-phenylpropenal (cinnamaldehyde) in tetrahydrofuran at
433 K and the total pressure 7 MPa was used as the model reaction for comparing the catalytic properties of the prepared catalysts.
It was demonstrated that a tin addition notably affected catalytic properties of ruthenium in the sense of a selectivity increment
related to the production of an unsaturated alcohol. 相似文献
37.
The development of piezoelectric immunosensors for human serum albumin (HSA) is reported. The piezoelectric crystals were modified either with monoclonal antibody AL-01 (direct assay) or with HSA (competitive assay). Measurements were carried out in the flow-through mode. Affinity interaction between albumin and the antibody was characterised. With immobilised antibody and HSA in solution, the kinetic association rate constant k(a) was 18 100 l mol(-1) s(-1) and the dissociation constant k(d) was 0.00369 s(-1). For the opposite arrangement (immobilised HSA), a slower dissociation was observed, k(d) was 0.00085 s(-1). A competitive assay for HSA was developed with working range of 1-5 mug ml(-1) and a total time for one analysis equal to 17 min. Samples of urine were analysed after tenfold dilution. The developed system was successfully evaluated on real samples from diabetic patients and the obtained results correlated well with the standard reflectometric assay of proteins in urine. 相似文献
38.
E. Makrlík P. Vaňura P. Selucký 《Journal of Radioanalytical and Nuclear Chemistry》2006,267(3):533-535
Summary Extraction of microamounts of calcium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B-) in the presence of 18-crown-6 (18C6, L) has been investigated. The equilibrium data have been explained assuming that the
complexes HL+, CaL2+and CaL are extracted into the organic phase. The values of extraction and stability constants of the complex species in nitrobenzene
saturated with water have been determined. 相似文献
39.
40.
In this contribution, the on-line coupling of solid phase extraction (SPE), based on a restricted-access material (RAM), with sequential injection technique (SIA) for the analysis of biological samples, is described. The SIA-RAM system was tested with a new potential antileucotrienic drug (VUFB-19363 (Quinlukast)) for serum analysis. The method is based on SPE with the novel internal-surface reversed-phase column packing material-alkyl-diol silica (ADS). The supports tolerate direct and repetitive injection of proteinaceous fluids (plasma, serum) and allow reversed-phase partitioning at the internal surface. A column packed with a 25 microm C18 alkyl-diol support was used for direct serum injection. Using a 6-port selection valve and the system of three mobile phases, the polar matrix compounds and metabolites are removed by sequentially aspirated mobile phases with lower content of the organic part (methanol-water (2:98) and following acetonitrile-water (20:80)) to the waste, and then, the analyte enriched on the column is eluted by a strong mobile phase (acetonitrile-methanol-water (40:20:40)) to the UV detector without transfer loss. With the fully automated SIA system, a total analysis time of less than 10 min was achieved. The only off-line sample pre-treatment step required to remove particulate matter was centrifugation. The studies showed a range of linearity (2-40 microg ml(-1)) and a high recovery (93.6-96.8%) of drug from the biological matrix with coefficients of variation (RSD) less than 5.0% (n = 6). This paper introduces a new, simple and robust analytical technique suitable for screening determination and direct analysis of drugs in biological materials. 相似文献