J. Serb. Chem. Soc. 63(6) 395 (1998)
IN
MEMORIAM
Hans-Joachim
Neumann
On March 5th,
1997, Prof. Dr. habit. H. J. Neumann died in Clausthal at the age of 66.
H. J.
Neumann studied chemistry at the TH Braunschweig. At the same university he
received his doctorate in 1959. In 1969 he qualified as University Teacher for
Chemical Engineering. In his 35 years of scientific research work he worked on
many aspects of chemistry, mainly petroleum chemistry. Since 1976 H.-J. Neumann
was an honorary professor at the Technical University, Clausthal. He
distinguished himself especially in the field of the composition of bitumens.
His research work on bitumen began in 1970 with the results of correlations
between chemical composition and practical relevant properties such as
rheology, aging and adhesion.
For the
bitumen industry Prof. Dr. Neumann was an important consultant and partner in
handling research work. His knowledge not only dissipated in the form of
lectures, but also in 100 publications now available to the scientific
community.
Besides
his research and education work he was further engaged in the education of
chemists and engineers. He authored the book "Bitumen and Its
Application". He has dedicated his knowledge and experience to the
education of young scientists in all parts of the world. More than 45
dissertations were completed under his guidance. Most of these were done at the
German Petroleum Institute (Institut f?r Erd”l - und Erdgasforschung, IFE). His
efforts, outstanding research work, and knowledge led to the national and
international fame of the IFE.
Prof. H.
J. Neumann was the principal investigator of the joint research project
"Synthetic Oil and Petrochemicals from Oil Shale and Polymer-Modified
Bitumens", which was carried out by the Faculty of Technology and
Metallurgy, Belgrade, the Highway Institute, Belgrade and the German Petroleum
Institute, Clausthal-Zellerfeld. He was a co-mentor of two Ph. D. dissertations
at the University of Belgrade and helped more than ten students of the Faculty
of Technology and Metallurgy, University of Belgrade, to do important
experimental measurements in his Institute. In 1990 H. J. Neumann, as the first
German scientist, was elected an honorary member from abroad of the Serbian
Chemical Society and for many years he was a member of the Editorial Board from
abroad of the Journal of the Serbian Chemical Society.
We mourn
an outstanding scientists and friend. We will miss his scientific experience
and help.
Iradj Rahiman and Jovan Jovanovic
J. Serb. Chem. Soc. 63(6) 397-418 (1998)
UDC 622.24/497.1/:665.51
JSCS-2544
Review paper
REVIEW
Organic
geochemical investigation of crude oils. The southeastern part of the Pannonian
Basin in Yugoslavia
BRANIMIR
S. JOVANCICEVIC*,**, PREDRAG S. POLIC*,** and DRAGOMIR K.
VITOROVIC**
*Faculty of Chemistry, University of Belgrade,
P. O. Box 158, YU-11001 Belgrade and
**Centre
of Chemistry ICTM, Njegoseva 12, Belgrade, Yugoslavia
(Received
13 January 1998)
1.
Introduction
2. Organic
geochemical characterisation of crude oils
3. Choice
of parameters
4. Crude
oils from the southeastern part of the Pannonian Basin
4.1.
General characteristics
4.2.
Biodegradation
4.3.
Origin
4.4.
Maturity
5.
Conclusions
Key words: organic
geochemistry, crude oils, correlation parameters, Pannonian Basin.
J. Serb. Chem. Soc. 63(6) 419-431 (1998)
UDC 665.45.002:66.094.3
JSCS-2515
Original scientific paper
Kerogen diversity demonstrated by oxidation.
III. Type
I-II kerogens
DRAGOMIR
VITOROVIC, ANDRE AMBLES*, SNEZANA BAJC, OLGA CVETKOVIC and
PREDRAG POLIC**
Centre of Chemistry, Institute of Chemistry,
Technology and Metallurgy,
Njegoseva
12, YU-11000 Belgrade, Yugoslavia,
*Department
of Chemistry, Faculty of Science, University of Poitiers, France, and
**Faculty
of Chemistry, University of Belgrade, P.O.Box 158, YU-11001 Belgrade,
Yugoslavia
(Received 9
February 1998)
A parallel
study of intermediate type I-II kerogens from shales of various geographic
origin (Timahdit and S. Pyongan shales and Estonian Kukersite) is described in
this paper. An optimised multistep alkaline permanganate degradation method was
used for their structural characterisation and differentiation. In addition to
the proportions of the three main types of acidic oxidation products, as the
basis for classification and characterisation, experimentally based
supplementary fourth parameters were also introduced, aimed at improving the
kerogen structural interpretations. Striking differences in the distribution of
various kinds of aliphatic and aromatic acids enabled the advanced structural
differentiation of seemingly similar kerogens.
Key words: kerogen,
type I-II; structural characterisation; alkaline permanganate degradation;
oxidation products.
J. Serb. Chem. Soc. 63(6) 433-437 (1998)
UDC 547.387:66.094.1:66.097.3
JSCS-2546
Original scientific paper
Reduction of some rigid ketones with thermally
activated Al(OH)3 and 2-propanol as
hydrogen donor
JOZE
FORSEK
Faculty of Chemistry, University of Belgrade,
Studentski trg 12-16, P. O. Box 158, and
Center
for Chemistry, ICTM, Njegoseva 12, YU-11000 Belgrade, Yugoslavia
(Received
30 December 1997)
The
reduction of some rigid ketones, 5a-cholestan-3-one (1), 4-tert-butylcyclohexanone
(4), 5a-cholestane-3,6-dione (7) and 5a-androstane-3,17-dione (10),
with thermally activated Al(OH)3 in refluxing 2-propanol as the hydrogen donor
has been investigated. The reduction afforded predominantly alcohols 3
and 6, as the result of a stereoselective reduction of ketones 1
and 4, and alcohols 9 and 12, as the result of both a
stereoselective and regioselective reduction of ketones 7 and 10.
Key words: reduction,
rigid ketones, activated Al(OH)3, 2-propanol.
J. Serb. Chem. Soc. 63(6) 439-443 (1998)
UDC 547.857.1:547.455.562.7:542.9
JSCS-2547
Original scientific paper
Stereoselective reduction of the C4 carbonyl group of methyl 2,3,6-tri-O-methyl-a-D-xylo-hexopyranosid-4-ulose.
Synthesis
of methyl 2,3,6-tri-O-methyl-a-D-galactopyranoside
DAVID
YEAGLEY and MOMCILO MILJKOVIC
Department
of Biochemistry and Molecular Biology, The M. S. Hershey Medical Center,
The
Pennsylvania State University, Hershey, PA 17033, USA
(Received
17 February 1998)
Reduction
of methyl 2,3,6-tri-O-methyl-a-D-xylo-hexopyranosid-4-ulose with
lithium tri-sec-butylborohydride gave methyl 2,3,6-tri-O-methyl-a-D-galactopyranoside
as the only detectable product. Reduciton of 1 by lithium aluminum
hydride gave a mixture of corresponding D-gluco- and D-galacto-derivatives in
3:4 ratio.
Key words: synthesis,
stereoselective reduction, methyl 2,3,6-tri-O-methyl-a-D-galactopyranoside.
J. Serb. Chem .Soc. 63(6) 445-453 (1998)
UDC 547.424.1:547.51
JSCS-2548
Original scientific paper
Substituted oxetanes in polymer synthesis.
III.
Polyesters based on 3,3-bis(chloromethyl)oxetane and various
dicarboxylates.
The
influence of the chemical structure upon thermal behaviour
VICTOR
BULACOVSCHI and VIOLETA TOADER
Technical University "Gh. Asachi"
Iasi, Macromolecular Department,
Bd.
Copou 11A, Iasi, RO-6600, Romania
(Received
26 November 1997, revised 23 February 1998)
This paper
presents some aspects regarding the synthesis and thermal behaviour of
polyesters, based on 3,3-bis(chloromethyl)oxetane (BCMO) and various
dicarboxylates. In order to explain the different behaviour of the reaction
systems, the reactivity of the dicarboxylate anions in the nucleophilic
replacement of the chlorine atom was estimated using an AM1 programme. The
polymers were characterized by 1H-NMR and DSC. Almost all the studied
polyesters show good thermal stability. The lop-sides connection of the
structural units to the main chain lowers the transition temperatures.
Key words: polymer
synthesis, polyesters, oxetanes, thermal behaviour.
J. Serb. Chem. Soc. 63(6) 455-466 (1998)
UDC 678.742:543.4
JSCS-2549
Original scientific paper
Optical microscopy analysis of the morphology
of isotactic polypropylene
ANITA
GROZDANOV and GORDANA BOGOEVA-GACEVA
University "St. Cyril and Methodius",
Faculty of Technology and Metallurgy,
Rugjer
Boskovic 16, Skopje, Macedonia
(Received
16 July 1997, revised 16 February 1998)
The melt
nucleation and crystallization, as well as the morphology of isotactic
polypropylene, i-PP, used as a matrix in long fibre reinforced composites, were
analysed by polarizing optical microscopy (POM). The investigations were
carried out dynamically and isothermally in the temperature regime (Tc =
116-136°C) with a cooling rate of 5 K min-1. It was found that the nucleation
density of i-PP decreases with increasing Tc, and, for the studied range of
crystallization temperatures, an induction period ranging from 3 s to 25 min
was determined. The growth rate of the spherulities was determined (4.7 - 0.14
µm/min) at different Tc values (119 - 136°C), and the crystallization energy
parameters were calculated. The value for the fold surface free energy, se, was
0.64×10-5 J cm-2, and the lamellae
thickness changed in the range from 436 to 642 nm, depending on the Tc.
Key words: i-PP,
crystallization, morphology, nucleation, polarizing optical microscopy.
J. Serb. Chem. Soc. 63 (6) 467-474 (1998)
UDC 546.562/547.962.3:541.573
JSCS-2550
Original scientific paper
Application of differential pulse polarography
to the study of the binding of Cu(II)-ions to albumin
JASMINA
VIDIC, DESANKA SUZNJEVIC and DUSAN VUCELIC*
Institute of General and Physical Chemistry,
Studentski trg 12-16/V, YU-11001 Belgrade and
*Faculty
of Physical Chemistry, Studentski trg 12-16, YU-11001 Belgrade, Yugoslavia
(Received 6
October 1997, revised 23 January 1998)
The
formation of the complex between copper(II)-ions and serum albumin has been
studied by differential pulse polarography (d.p.p.) using 100 mM KCl/10 mM
NaHCO3 solution, pH 7.8 and
50 mM citrate buffer/100 mM KCl/10 mM NaHCO3, pH 6.0, as the supporting
electrolytes. It was found that the presence of citrate, as a strong chelator
of copper, causes a decrease in the number of Cu(II)-ions bound to albumin.
Unspecifically bound Cu(II)-ions could be removed during the time of incubation
from both buffers studied. It has been demonstrated that d.p.p., with a working
dropping mercury electrode, can be a useful technique for studying protein-metal
interactions directly in solution.
Key words: bovine
serum albumin, copper(II) complex, differential pulse polarography.
J. Serb. Chem. Soc. 63(6) 475-480 (1998)
UDC 577.18:543.544.2/.8
JSCS-2551
Original scientific paper
Determination of sodium fusidate in dosage
forms by high performance liquid chromatography
SOTE
VLADIMIROV, LJILJANA IVANISEVIC*, DANICA AGBABA, JASMINA BRBORIC and
DOBRILA ZIVANOV-STAKIC
Department of Pharmaceutical Chemistry and Drug
Analysis, Faculty of Pharmacy, P. O. Box 146, 11152 Belgrade, and
*Department
of Pharmacy, Vojvode Stepe 458, Belgrade, Yugoslavia
(Received
20 November 1997, revised 6 January 1998)
A simple
HPLC procedure, suitable for the determination of sodium fusidate (SF) in
dosage forms, was developed. The method involves using a UV detector (208 nm)
in the presence of basic buffered media (pH 7.25) under reversed-phase
conditions (Supelcosil® LC18TM, 3 mm particles). The linear regression
between the concentration of SF and the peak area, y = -4.4566 + 8.9238 x
with a coefficient of correlation r = 0.9985, was confirmed for SF in
the concentration range from 25 µg ml-1 to 150 µg ml-1. The detection limit
of SF was 12.5 µg ml-1. The HPLC method was
applied for the determination of SF in dosage forms: Stanicid®
coated tablets, Stanicid® ointment and Stanicid® sterile
gauze dressing. The concentrations and statistical parameters of sodium
fusidate for all the investigated dosage forms were satisfactory and ranged
from 100.41 to 105.39% (the R. S. D. ranged from 1.51 to 2.75%).
Key words: Rp-HPLC,
UV-detection, sodium fusidate, raw material, dosage forms.
J. Serb. Chem. Soc. 63(6)481-487(1998)
UDC 577.164.1:543.2
JSCS-2552
Original scientific paper
Kinetic determination of pyridoxine
hydrochloride in pharmaceutical samples
S.
S. MITIC, G. Z. MILETIC, S. M.MILETIC and D. A. KOSTIC
Department of Chemistry, Faculty of Philosophy,
University of Nis, YU-18000 Nis, Yugoslavia
(Received
22 November 1997, revised 23 January 1998)
A kinetic
method is described for the determination of pyridoxine hydrochloride based on
its inhibiting effect on the Mn(II) catalysis of the oxidation of malachite
green with potassium periodate. The sensitivity of the method is 0.2 mg cm-3. The relative error
ranges between 3.5 and 11.0% for the concentration interval 2.0 to 0.2 mg cm-3. Kinetic equations are
proposed for the investigated process .The effects of certain foreign ions upon
the reaction rate were determined for the assessment of the selectivity of the
method. The method was applied to determine pyridoxine hydrochloride in
pharmaceutical samples.
Key words: kinetic
method, pyridoxine hydrochloride determination, malachite green oxidation,
pharmaceutical samples.
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