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21.
A. A. Abd El Raheem Abdel Aziz Amin A. S. Moustafa 《Fresenius' Journal of Analytical Chemistry》1960,172(5):347-356
Summary Omega Chrome Fast Blue 2G has been found to be a suitable indicator for the detection of the equivalence point of calcium, magnesium and manganese in the presence of cadmium, nickel, and aluminium, when they are masked by the addition of cyanide or triethanolamine. It is also a suitable indicator for the back titration of aluminium using calcium or magnesium as a back titrant.This dye has also been found to be a suitable reagent for the colorimetric determination of calcium, magnesium, manganese and thorium. 相似文献
22.
Mohammed Ejaz 《Mikrochimica acta》1976,65(6):643-650
Summary Radiochemical procedures have been worked out to prepare234Th(UX1) with and without carrier from uranium using N-oxide of 4-(5-nonyl)pyridine in sulphuric acid media. This reagent has also been employed in the development of a combined solvent extraction-ion exchange-spectrophotometric method for the determination of thorium in various samples.
Zusammenfassung Radiochemische Methoden zur Herstellung von234Th(UX1) aus Uran mit und ohne Träger und unter Verwendung von 4-(5-Nonyl)pyridin-N-oxid in schwefelsaurer Lösung wurden ausgearbeitet. Dieses Reagens wurde auch für die Ausarbeitung einer Thoriumbestimmung in verschiedenartigen Proben auf der Grundlage von Extraktion, Ionenaustausch und Spektro-photometrie verwendet.相似文献
23.
The present work is dedicated to the XRD, ED and HREM characterization of a new bismuth copper oxyphosphate Bi∼6.2Cu∼6.2O8(PO4)5 (a=11.599(2)Å, , c=37.541(5)Å, R1=0.0755, Rw2=0.174, G.S Pn21a). The relatively long size of its c parameter is due to the arrangement along this direction of two kinds of ribbon-like polycations formed by edge sharing O(Bi, Cu)4 tetrahedra. The existence of such cations is characterized by the b∼5.2 Å value intrinsic to the ribbons structure and commonly found in bismuth oxyphosphate materials. In the title compound, 2-tetrahedra wide [Bi∼2.4Cu∼3.6O4]6.4+ and 3-tetrahedra wide [Bi∼5Cu∼3O6]9+ ribbons are isolated by phosphate groups and alternate along c. The interstitial site created between two different sizes ribbons is occupied by Cu2+ cations disordered over several close crystallographic sites. The mixed Bi3+/Cu2+ nature of certain edge-of-ribbons positions induces a disorder over several configurations of the phosphate groups. The concerned oxygen atoms form the environment of the disordered interstitial Cu2+ cations which occupy tunnels formed by the phosphate anions. The high-resolution electron microscope study enables a precise correlation between the observed images and the refined crystal structure, evidencing the polycations visualization. Furthermore, this material being the second example of partially disordered compound similar chemical system, some topological rules can be deduced. The b-axis doubling was observed by ED and HREM and is assigned to the ordering of interstitial Cu2+ within tunnels cations. A partial intra-tunnel ordering was also observed. 相似文献
24.
S. Allaoud H. Bitar M. El Mouhtadi B. Frange 《Journal of organometallic chemistry》1983,248(2):123-130
13C NMR spectra and complete assignment by means of coupled spectra and off resonance experiments, are reported for a new kind of organoboron heterocycle and the related borazine (o-CH3C6H4NBCH3)3; π-charge densities, obtained from LCAO-MO Hückel calculations, are in reasonable agreement with experimental chemical shifts for the former compound. 相似文献
25.
A fundamental study was made on the reduction of calcium phosphate by carbon. The mechanism of reduction was presented on applying different additions. Both silica and alumina increased the extent of reduction but with variable rates. The activation energies were calculated on the basis of first-order reactions. The phases formed during reduction were investigated by X-ray analysis. 相似文献
26.
Emulsion liquid membranes (ELM) with di-2-ethylhexylphosphoric acid in n-alkane, and dipicrylamine and cobalt(III) dicarbollide in nitrobenzene stabilized in double emulsions by SPAN 80/85 surfactant were used for preconcentration of radioactive fission products (137Cs,90Sr,139Ce, and152Eu) from slightly acidic nitrate solutions. The efficiency of sulfuric, phosphotungstic and silicotungstic acids as stripping agents, and picric acid as the bulky anion additive was investigated. A group separation of the fission products is possible by the ELM technique and can be considered for their removal from waste water solutions. 相似文献
27.
28.
Mohammed R. Arshadi 《Journal of mass spectrometry : JMS》1978,13(7):379-381
The 70 eV positive and negative ion mass spectra of the oxygen, sulphur and selenium 2,1,3-benzodiazoles have been studied. The influence of hetero atom on the fragmentation modes of the benzodiazole molecular ions has been discussed. 相似文献
29.
1-Phenyl-2-(benzenesulphonyl)-ethylene and 1-phenyl-2-(benzenesulphonyl)-prop-1-ene have been shown to undergo ,-photoisomerisation, whereas 2-benzenesulphonylindene readily forms [π2 + π2] photoadducts with 2,3-dimethylbut-2-ene, cyclopentene, and cyclohexene. 相似文献
30.
Ayoub Mourjane Hafida Hanine El Mustapha El Adnany Mourad Ouhammou Nadia Hidar Bouchra Nabil Ahcne Boumendjel Khalid Bitar Mostafa Mahrouz 《Molecules (Basel, Switzerland)》2022,27(10)
Argania spinosa L. Skeels is an emblematic tree in Morocco, known worldwide for its medicinal and nutritional value. Its fruits contain kernels used to prepare an edible oil, the leaves are used to feed livestock, and its wood is used as fuel. If the oil acquires high importance, the other components of the fruit of the argan are undervalued. Our objective is to invest the waste of the argan industry. Particularly, our study aimed to assess the effect of thermal activation of argan pulp on its therapeutic value, its phenolic profile and its functional and physicochemical properties. After heat treatment, the HPLC analysis for the average total phenolic content varied from 2% to 37%, depending on temperature. The antioxidant activity was increased with heat treatment. Higher values of antioxidant activity, polyphenol and pigment content were recorded at 70 °C. Functional properties analysis indicated that water solubility index and water absorption capacity were significantly affected by heat stress. Physicochemical analysis showed that moisture content, titratable acidity and soluble solids were affected. 相似文献