Search results for "nuclear chemistry"
showing 10 items of 1124 documents
pH-sensitive hydrogel based on a polyaspartamide derivative
2006
A pH-sensitive hydrogel was prepared by UV irradiation technique. Starting polymer was obtained from alpha,beta-poly (N-2-hydroxyethyl)-DL-aspartamide (PHEA) partially derivatized with glycidyl methacrylate (PHG). The PHG copolymer was cross-linked by UV irradiation in the presence of methacrylic acid (MA) to form a pH sensitive hydrogel. The cross-linked matrix shaped as microparticles was characterized by FT-IR spectrophotometry, XPS, X-ray diffraction, SEM and particle size distribution analyses. Moreover, to have information about water affinity of the prepared sample, swelling measurements were carried out in aqueous media mimicking some biological fluids. In order to employ the prepar…
Comparison of the interaction of cobalt bovine carbonic anhydrase II with acetazolamide and methazolamide and the reaction of apoenzyme with cobalt(I…
2003
The metalloenzyme carbonic anhydrase (CA) is an attractive choice for a research-based bioinorganic laboratory course. In this project the interaction of cobalt bovine carbonic anhydrase II (CoBCAII) with acetazolamide and methazolamide and the reaction of apoenzyme with cobalt(II) complexes of acetazolamide and methazolamide is studied by UV-visible spectroscopy. Prior to this spectroscopic study students are given native BCAII, and they prepare apoBCAII and CoBCAII. A major aim is to provide experience in handling metalloproteins and in the study of metal complexes-protein interactions.
Mimonoside D: a new triterpenoid saponin from Mimosa diplotricha Sauvalle (Fabaceae)
2021
A new triterpenoid saponin (Mimonoside D: 3-O-��-L-arabinopyranosyl-3��-hydroxyolean-12-en-28-oic acid 28-O-��-D-xylopyranosyl-(1���2)-��-D- glucopyranoside ester (1)) was isolated from the aerial parts of Mimosa diplotricha Sauvalle together with nine known compounds: 7,4���-dihydroxyflavone (2), kaempferol (3), lupeol (4), betulinic acid (5), ��-sitosterol (6), ��-sitosterol-3-O-��-D-glucopyranoside (7), lutein (8), 5,2���-dihydroxy-7,4���,5���-trimethoxyflavone (9) and vitexin (10). Their structures were elucidated on the basis of spectroscopic (1 D and 2 D nuclear magnetic resonance) and high-resolution mass spectrometric data as well as by comparison of their spectral data with those o…
Discelectrophoretischer Nachweis der Heterogenität der menschlichen sauren Spermaphosphatase
2009
Zusammenfassung Mit Hilfe der vertikalen Discelektrophorese in Polyacrylamid-Gel ist es moglich, zwei Enzymbanden der sauren Spermaphosphatase nachzuweisen. Eine optimale Trennung ergibt sich bei einer Wasserstoffionenkonzentration von pH 7,5 im Trenn-Gel und pH 5,5 im Sammel-Gel und 0,1 M Acetatpuffer. Der Vorteil dieser Methode liegt in dem relativ geringen apparativen Aufwand, der kurzen Trennzeit, der hohen Trennscharfe sowie der Moglichkeit, aserst geringe Substanzmengen aufzutrennen. Summary With the aid of disc-electrophoresis in poly acryl amide it is possible to proof the heterogeneity of acid phosphatase of human seminal fluid. In all samples could be detected. The best results we…
Effective Removal and Mineralization of 8-Hydroxyquinoline-5-sulfonic Acid through a Pressurized Electro-Fenton-like Process with Ni−Cu−Al Layered Do…
2020
Ni−Cu−Al layered double hydroxide (Ni−Cu−Al LDH) was proposed as an electro‐Fenton‐like catalyst for 8‐hydroxyquinoline‐5‐sulfonic acid (8‐HQS) removal in water. The properties of the prepared catalysts were characterized by using X‐ray, SEM and EDAX analyses. The effect of numerous operative parameters on the removal of 8‐HQS and total organic carbon (TOC) was studied. Very high level removal of both 8‐HQS and TOC (87 and 79 %, respectively) were obtained by using a pressurized electro‐Fenton‐like process (PrEFL‐LDH) at P=10 bars, using a Ti/IrO2‐Ta2O5 anode for 6 h. The process presented good performances in a large range of pH (3–10) and gave better removals of 8‐HQS and TOC with respect…
2017
The title compound, C12H14Br2, was prepared by bromination/dehydrobromination ofE,E,Z-cyclododecatriene. The crystal is composed ofC2-symmetrical molecules with anEconformation of the bromoalkene fragments and nearly linear alkyne units. The torsion angles in the ring suggest significant ring strain.
Crystal structures of isomeric 3,5-dichloro-N-(2,3-dimethylphenyl)benzenesulfonamide, 3,5-dichloro-N-(2,6-dimethylphenyl)benzenesulfonamide and 3,5-d…
2017
The crystal structures of three isomeric compounds of formula C14H13Cl2NO2S, namely 3,5-dichloro-N-(2,3-dimethylphenyl)-benzenesulfonamide (I), 3,5-dichloro-N-(2,6-dimethylphenyl)benzenesulfonamide (II) and 3,5-dichloro-N-(3,5-dimethylphenyl)benzenesulfonamide (III) are described. The molecules of all the three compounds are U-shaped with the two aromatic rings inclined at 41.3 (6)° in (I), 42.1 (2)° in (II) and 54.4 (3)° in (III). The molecular conformation of (II) is stabilized by intramolecular C—H...O hydrogen bonds and C—H...π interactions. The crystal structure of (I) features N—H...O hydrogen-bonded R 2 2(8) loops interconnected via C(7) chains of C—H...O interactions, forming a thre…
(E)-1-(1,3-Benzodioxol-5-yl)-3-(2,4,5-trimethoxyphenyl)prop-2-en-1-one
2017
The molecule of the title compound C19H18O6, adopts anEconformation about the C=C double bond and the C—C=C—C torsion angle is −179.30 (16)°. The molecule is nearly planar, as indicated by the dihedral angle of 6.99 (6)° between the benzene ring and the benzodioxalane ring. In the crystal, molecules are linkedviaweak C—H...O hydrogen bonds, forming zigzag chains propagating along thebaxis.
Phase selective synthesis of ZnS nanoparticles from structurally new dithiocarbamate precursor
2015
Abstract A phase selective solvothermal synthesis of ZnS (wurzite) nanoparticles with a flower-like morphology using a dithiocarbamate precursor, [Zn(4-dpmpzdtc)2(dpmpz)] (1) (where, dpmpz=(diphenylmethyl)piperazine), is described. The nanoparticles were identified as ZnS (wurzite) with the particle size of about 3 to 10 nm by scanning and transmission electron microscopy as well as powder X-ray diffraction (XRD). In addition, the precursor complex 1 was characterized using single crystal X-ray diffraction.
CMPO-substituted calix[6]- and calix[8]arene extractants for the separation of An3+/Ln3+ from radioactive waste
2006
Abstract Three calix[6]arene derivatives ( 1a – c ) and two calix[8]arene derivatives ( 2a , b ), with six and eight CMPO residues, respectively, attached to the narrow/lower rim via ether links, were synthesised. Preliminary liquid–liquid extraction studies for Eu(III) and Am(III) from aqueous nitric acid to o -nitrophenylhexyl ether reveal remarkable properties with respect to efficiency and selectivity, especially for the tert -butylcalix[6]arene derivative with a –(CH 2 ) 3 – spacer.