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Prikaz rezultata 301-310 od 318
Study of the structure of phenol-formaldehyde novolac resins by NMR spectroscopy and gel-permeation chromatography
(Serbian Chemical Society, Belgrade, 1999)
C-13-NMR spectroscopy and gel-permeation chromatography studies were carried out on different samples of typical commercial phenol-formaldehyde novolac resins. Six random novolac resins (NLO 1-6), with decreasing ratios ...
C-13 NMR spectra of pyridine chalcone analogs
(Elsevier, Amsterdam, 1999)
C-13 NMR spectra of two series of pyridine chalcone analogs were determined in deuterated dimethylsulphoxide (DMSO-d(6)). It was established that these compounds were in more stable E-configurations except for the ...
Simultaneous presentation of VLE, H-E and c(p)(E) by the PRSV equation of state with the modified van der Waals one-fluid and Huron-Vidal-Orbey-Sandler mixing rules
(Elsevier, Amsterdam, 1999)
The Stryjek-Vera modification of the Peng-Robinson equation of state with two parameter van der Waals one-fluid mixing rule suggested by Schwartzentruber and Renon (SR) and the Orbey-Sandler modification of the Huron-Vidal ...
Reactivity of beta-aroylacrylic acids with diazodiphenylmethane (vol 63, pg 359, 1998)
(Srpsko hemijsko društvo, Beograd, 1999)
Cobalt(II)-exchange in Zeolite A
(Akadémiai Kiadó, 1995)
The influence of the initial Co(2+) and Na(+) concentrations (Co(Co) and Co(Na), respectively) upon the exchange degree (y) of Na(+) by Co(2+) ions in Zeolite A at 20 oC has been studied. The observed increase of y with ...
Glycidyl esters synthesis catalysed by ion-exchange resins
(Serbian Chemical Society, Belgrade, 1996)
Ion-exchange resins not previously used for this purpose were employed to study the synthesis of glycidyl esters. The reaction was carried out both with free acids and their sodium salts. The model reaction was the synthesis ...
RTD analysis of a novel Taylor-Couette flow device for blood detoxification
(Amer Inst Chemical Engineers, New York, 1999)
Heparin is an anticoagulant used in extracorporeal procedures such as hemodialysis and open heart surgery. Unfortunately: heparin may induce potentially fatal complications in patients at high risk of bleeding. The use of ...
A study of the tetrahallogenonickel(II) complexes by the Fenske-Hall molecular orbital method
(Society of Chemists and Technologists of Macedonia, 1995)
The coordination geometry and electronic structure of the NiX4(2-) complex ions (X=Cl, Br, I) have been studied by the Fenske-Hall SCF method. The calculation confirm the presence of tetrahedral over square-planar geometry. ...
(31)P NMR investigation of some microporous zincophosphates
(Serbian Chemical Society, 1996)
High field magic-angle spinning (MAS) (31)P-NMR investigations of novel porous zincophosphates and their cobalt-containing derivatives confirm the framework structure of alternating Zn(Co)O4 and PO4 tetrahedra. The MAS NMR ...
On the possibility of the direct preparation of the sodium salt of copper phthalocyanine-4-sulfonic acid
(Serbian Chemical Society, 1994)
The reaction of a 1:3 molar mixture of the monosodium salt of 4-sulfophthalic acid and phthalic acod, carried out in the presence of NH4Cl, urea, CuSO4 5H2O, and (NH4)2MoO4, does not yield the mono-substituted derivative, ...