- Type of paper
: Paper in book
Title: Biosurfactants in Food Applications
- Authors:
- Velikonja, Joran (69734)
- Košarić, Naim
- Editors
- Košarić, Naim
Publisher: M. Dekker
ISBN: TP24.B57B58
Year: 1993
Pages: from 419 to 446
Language: engleski
Summary: Biosurfactats of the importance for food industries are
described. Technological processes of their productions are explained. The
most important properties of this group of very interesting compounds are
given. The most important applications of biosurfactants in the field of
food industry is also presented.
Keywords: biosurfactants, production of, properties of, applcation of, food industry
Other: UDC No.: 888'.14--dc20
CIP No.: 92-40312
- Type of paper
: Paper in journal
Title: Spectrophotometric investigation of
2-(2-pyridilmethyleneamino)phenol complexes with cobalt(II) and nickel(II)
in methanol/water solutions
- Authors:
- Grabarić, Zorana
- Grabarić, Božidar (14042)
- Koprivanac, Natalija
- Eškinja, Ivan
Journal: Chemical Papers
Number: 5
Volume: 47
Year: 1993
Pages: from 282 to 287
Number of references: 17
Language: engleski
Summary: The complexes of 2-(2-pyridylmethyleneamino)phenol with
Co(II) and Ni(II) ions were investigated by spectrometric methods. UV/VIS
measurements have been done using a computerized system. Stability
constants of the complexes have been determined. Possible application of
the investigated ligand for analytical determination of Co(II) and Ni(II)
ions have also been investigated and discussed.
Keywords: 2-(2-pyridylmethyleneamino)phenol, cobalt complexes of, nickel complexes of, spectrometric measurements
- Type of paper
: Paper in journal
Title: Electrochemical investigation of dopamine and pyrocatechol
with unmodified and banana tissue modified carbon paste electrode (in
press)
- Authors:
- Grabarić, Božidar (14042)
- Kruhak, Ivan (24133)
- Velikonja, Joran (69734)
- Tkalčec, Mihael (49616)
Journal: Prehrambeno-tehnološka i biotehnološka revija
Number: 4
ISSN: 0352-9193
Volume: 31
Year: 1993
Pages: from 131 to 135
Number of references: 16
Language: engleski
Summary: The electrochemical investigations of a neurotransmitter
and drug, dopamine and an air pollutant, pyrocatechol, with unmodified and
banana tissue modified carbon paste electrode were performed with cyclic
voltammetry and differential pulse voltammetry in batch mode and with
chronoamperometry in flow injection mode.
Keywords: dopamine, pyrocatechol, electrochemical biosensor, carbon paste electrode modified with banana tissue, cyclic voltammetry, chronoamperometry, flow injection analysis
- Type of paper
: Paper in journal
Title: Low-cost computerized enhancement of an analogue
densitometer performance (professional paper)
- Authors:
- Milardović, Stjepan (154444)
- Tkalčec, Mihael (49616)
- Grabarić, Božidar (14042)
Journal: Kemija u industriji
Number: 7
ISSN: 0022-9830
Volume: 43
Year: 1994
Pages: from 309 to 313
Number of references: 17
Language: engleski
Summary: On-line interfacing of an analogue densitometer and the
possibility of imediate calculation of the parameters charecterizing the
quality of photomaterial improved significantly the performance of the
analogue instrument, which is of high importance for product quality
control.
Keywords: computerized measurement, densitometer, photomaterial
- Type of paper
: Paper in journal
Title: Conditions for glukose determination bz amperometric
enzyme sensors based on glucose oxidase immobilized in an
electropolymerized film
- Authors:
- Iveković, Damir
- Rumenjak, V
- Kruhak, Ivan (24133)
- Milardović, Stjepan (154444)
- Tkalčec, Mihael (49616)
- Grabarić, Božidar (14042)
Journal: Biochemia Medica
Number: 1
ISSN: 1330-0962
Year: 1995
Pages: from 3 to 10
Number of references: 8
Language: hrvatski
Summary: Electrochemically polymerized films of phenol or pyrrole
were used for glucose oxidase immobilization on a graphite electrode. The
immobilized enzyme activity toward glucose oxidation was maintained and
hydrogen peroxide generated by the enzyme catalyzed reaction of glucose
with oxygen was detected at 0.9 V vs. saturated calomel electrode. The
sensors showed a fast response (< 5 s), good sensitivity and linear range
up to 4.5 mM. Dependence of the sensor response on film thikness is
discussed. Electrode fouling by proteins in blood serum was investigated
and a method for electrode cleaning is proposed.
Keywords: electrochemical biosensor, glucose, electropolymerized film
- Type of paper
: Paper in journal
Title: Presentation of physical quantities in chemistry and
biochemistry (professional paper)
- Authors:
- Grabarić, Božidar (14042)
Journal: Prehrambeno-tehnološka i biotehnološka revija
Number: 1
ISSN: 0352-9193
Volume: 31
Year: 1993
Pages: from 19 to 33
Number of references: 24
Language: hrvatski
Summary: The IUPAC recommendation on presenting the experimental
results in the field of chemistry and biochemistry are given. The most
often encountred errors in the manuscripts, as well as, those in some
books, are outlined.
Keywords: IUPAC recommendations, physical quantities, physical units
- Type of paper
: Paper in proceedings
Title: Molecular and ionic recognition in (bio)chemical sensors
- Authors:
- Grabarić, Božidar (14042)
- Editors
- Bogunović, Nikola
- Jović, Franjo
Proceedings title: Umjetna inteligencija pri mjerenju i vođenju
Language: hrvatski
Place: Zagreb
Year: 1992
ISBN/ISSN: 920731032
Pages: from 25 to 30
Meeting: Umjetna inteligencija pri mjerenju i vođenju
Held: from 06/10/92 to 06/11/92
Summary: An overview of the principles of molecular and ionic
regnitions are given. New compounds selective towards specific compounds
have been presented. Several important systems which are successfully
applied in (bio)chemical sensors are demonstrated.
Keywords: chemical sensors, biosensors
- Type of paper
: Summary in proceedings
Title: Electrochemical investigaton of dopamine and pyrocatechol
with banana tissue modified carbon paste electrode
- Authors:
- Grabarić, Božidar (14042)
- Kruhak, Ivan (24133)
- Velikonja, Joran (69734)
Proceedings title: Abstract Book, V Italo-Hung. Symp. on Spectrochem. Qual. Control and Assur. in
Language: engleski
Place: Rim, Italija
Year: 1991
Pages: from 130 to 130
Meeting: Fifth Italo-Hungarian Symposium on Spectrochemistry Quality Control and Assurance in Life Sciences
Held: from 09/09/91 to 09/13/91
Summary: Investigation of the banana tissue modified carbon
pasteelectrode as a new sensor for dopamine and pyrocatechol has
beenperformed. Cyclic and differential pulse voltammetricmeasurements have
been done and chronoamperometric detection inflow injection mode has also
been shown together with aconstruction of new FIA cell. Literature data
about sensitivityand selectivity of dopamine detection have been confirmed
but forpyrocatechole it was found, contrary to the literature findings,that
unmodified and electrochemically activated carbon pasteelectrode is giving
better response than banana tissue modifiedone.
Keywords: bosensor, carbon paste electrode, dopamine determination, pyrocatechol determination, voltammetry, chronoamperometry, FIA cell
- Type of paper
: Summary in proceedings
Title: Purified adn fractionated poly(vinylchloride) as a
membrane material for ion selective electrodes
- Authors:
- Borovnjak-Zlatarić, Biserka (4673)
- Grabarić, Božidar (14042)
- Mencer, Helena Jasna
- Marinić, Ljiljana
Proceedings title: Zbornik sinopsisa XIII. skupa hrvatskih kemičara
Language: hrvatski
Place: Zagreb
Year: 1993
Pages: from 212 to 212
Meeting: XIII. sastanak hrvatskih kemičara
Held: from 02/08/93 to 02/10/94
Summary: PVC of high molar mass is purified and fractionated on
three fractions. Membranes were prepared from original, purified and
fractionated PVC using dioctylphtalate as plasticizer and
dibenzo-18-crown-6 as ionophore for Na+ and K+ ions. The structure of the
membranes was investigated using electronic microscope. Selectivity
coefficients were determined. The best results were obtained using original
unpurified and nonfractionated PVC, probably due to the influence of
impurities, usuallz the remains of emulgator, on ion-selective properties.
Keywords: ion selective electrodes, PVC membranes, dibenzo-18-crown-6, Na+, K+
- Type of paper
: Summary in proceedings
Title: Electrochemical and spectrophotometric investigation of
Ta6Br12 8H2O cluster complex in aqueous solutions
- Authors:
- Murković, Ivana (178963)
- Tkalčec, Mihael (49616)
- Grabarić, Božidar (14042)
- Brničević, Nevenka
Proceedings title: Zbornik sinopsisa XIII. skupa hrvatskih kemičara
Language: hrvatski
Place: Zagreb
Year: 1993
Pages: from 184 to 184
Meeting: XIII. sastanak hrvatskih kemičara
Held: from 02/08/93 to 02/10/93
Summary: Electrochemical properties of (Ta6Br12)2+ cluster complex
ion in aqueous solutions of 0.1 M HClO4 were investigating using cyclic
voltammetry. It was possible to oxidize chemically and electrochemically
this cluster ion into (Ta6Br12)3+ and (Ta6Br12)4+ cluster ions, each of
which shows it own UV/VIS spectrum.
Spectrophotometric investigation has also been done together with
preliminary investigation of chemical and electrochemical kinetics.
Keywords: cluster complexes, (Ta6Br12)2+, (Ta6Br12)3+, (Ta6Br12)4+, cyclic voltammetry, UV/VIS spectrophotometry
- Type of paper
: Summary in proceedings
Title: Influence of the composition of mixed solvent
methanol/water on the stability of metal ion complexes with propanoates and
2-hydroxypropanoates
- Authors:
- Kruhak, Ivan (24133)
- Grabarić, Božidar (14042)
Proceedings title: Zbornik sinopsisa XIII. skupa hrvatskih kemičara
Language: hrvatski
Place: Zagreb
Year: 1993
Pages: from 183 to 183
Meeting: XIII. sastanak hrvatskih kemičara
Held: from 02/08/93 to 02/10/93
Summary: Stability constants of successive metal ion complexes with
propanoate and 2-hydroxypropanoate have been determined in aqueous and
mixed methanol/water solutions with different volume fractions at constant
temperature, 25.0 +- 0.1 oC, and at constant ionic strength, 0.1 M
(NaClO4). Potentiometric method was applied using glass electrode and
stability constants at different volume fraction of methanol were obtained
using nonlinear method of least squares. On the basis of this constants
using linear extrapolation the values of stabilitz constants which are
independent on composition of the mixed solvent have been calculated.
Keywords: stability constants, Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Pb(II), propanoate complexes of, 2-hydroxypropanoate complexes of, methanol/water mixed solvent
- Type of paper
: Summary in proceedings
Title: Design of the spectrophotometric system co9nstructed by
interfacing the computer to the UV/VIS spectrophotometer Varian DMS-80
- Authors:
- Premec, Goran
- Grabarić, Božidar (14042)
- Tkalčec, Mihael (49616)
Proceedings title: Zabornik sinopsisa XIII. skupa hrvatskih kemičara
Language: hrvatski
Place: Zagreb
Year: 1993
Pages: from 182 to 182
Meeting: XIII. sastanak hrvatskih kemičara
Held: from 02/08/93 to 02/10/93
Summary: Computerized system for UV/VIS spectrophotometry is
designed and built by interfacing a commercial spectrophotometer Varian
DMS-80 with computer. Hardware and software has been developed for
instrument control and measurement and storage of spectrophotometric data
(lambda and A) in data files accesible to own programs or to commercial
software packages.
Classical and computerized (normal and derivative spectrophotometry)
measurements were compared and discussed on selected examples.
Keywords: UV/VIS spectrophotometry, computerized measurements
- Type of paper
: Summary in proceedings
Title: Computerized enhancement of measurement performance and
data evaluation of an analogue densitometer
- Authors:
- Milardović, Stjepan (154444)
- Tkalčec, Mihael (49616)
- Grabarić, Božidar (14042)
Proceedings title: Zbornik sinopsisa XIII. skupa hrvatskih kemičara
Language: hrvatski
Place: Zagreb
Year: 1993
Pages: from 181 to 181
Meeting: XIII. sastanak hrvatskih kemičara
Held: from 02/08/93 to 02/10/93
Summary: Design, construction and application of three on-line
systems for computerized analogue densitometer measurement and data
evaluation are described. The systems are valuable for quality control of
x-ray photographic materials, one of them in "Fotokemika" factory in
Zagreb.
Numerical and statistical determination of characteristic parameters of
photographic material is performed. The results obtained in conventional
way and those using computerized system are compared. Samples of x-ray
photographic materials have been analysed.
Keywords: photometry, computerized densitometry, computerized sensitometry, medical x-ray film
- Type of paper
: Summary in proceedings
Title: Construction of the microelectrochemical cell with carbon
paste electrode as a sensor for electrochemical detection in FIA and LC
- Authors:
- Kruhak, Ivan (24133)
- Grabarić, Božidar (14042)
Proceedings title: Zbornik sinopsisa XIII. skupa hrvatskih kemičara
Language: hrvatski
Place: Zagreb
Year: 1993
Pages: from 185 to 185
Meeting: XIII. sastanak hrvatskih kemičara
Held: from 02/08/93 to 02/10/93
Summary: Microelectrochemical cell of 1.5 microliter volume and
working electrode of carbon paste is designed and constructed for FIA and
LC analysis. Modifying carbone paste with living cell tissue a selective
biosensor can be obtained.
The advantage of this cell, beside its small volume, is that it can be
easily dismounted for regeneration of the surface of carbon paste. It is
made of polyethylene and silicone rubber, while input tube can be either of
stainless steel or glass.
The results of cell application for dopamine and pyrocatechol determination
using banana tissue modified carbon paste electrode using FIA is presented.
Keywords: microelectrochemical cell, carbon paste electrode, carbon paste electrode modified with banana tissue, biosensor, dopamine, pzrocatechol, flow injection analysis, liquid chromatography
- Type of paper
: Summary in proceedings
Title: Application of MATHCAD in education - Digital filtering
and deconvolution with FFT
- Authors:
- Ferber, Tomislav
- Grabarić, Božidar (14042)
Proceedings title: Zbornik sinopsisa XIII. skupa hrvatskih kemičara
Language: hrvatski
Place: Zagreb
Year: 1993
Pages: from 376 to 376
Meeting: XIII. sastanak hrvatskih kemičara
Held: from 02/08/93 to 02/10/93
Summary: The possibility of using commercial software package
MATHCAD for digital filtering and deconvolution using FFT of multianalyte
sensor signals were investigated.
Keywords: digital filtering, deconvolution, fast Fourier transforms, global multianalyte signals
- Type of paper
: Summary in proceedings
Title: Influence of the blood proteins on the properties of
chloride and potassium ISE during blood analsis
- Authors:
- Kruhak, Ivan (24133)
- Milardović, Stjepan (154444)
- Borovnjak-Zlatarić, Biserka (4673)
- Iveković, Damir
- Rumenjak, V
Proceedings title: Sinopsisi XIV. skupa hrvatskih kemičara
Language: hrvatski
Place: Zagreb
Year: 1995
Pages: from 286 to 286
Meeting: XIV. skup hrvatskih kemičara i IV. hrvatski simpoyij o kemiji i tehnologiji makromolekula
Held: from 02/06/95 to 02/08/95
Summary: Using computerized electrochemical system and
electrochemical sensors, measurements of potassium and chloride were made
in blood samples. The influence of proteins in blood on reproducibility and
response time of the sensors were investigated. All measurements were made
in the cell of approx. volume of 30 microliters using 90 microliters of
samples. Commercial rinsing solutions were used between the measurements.
Electrochemical sensors previously developed in the Laboratory of General
and Inorganic Chemistry of the Faculty of Chemical Engineering and
Technology were used. Aqueous solutions and blood serum with known
potassium and chloride concentration were used as standard solutions.
Keywords: senzors for potassium, sensors for chlorides, ion selective electrodes, measurements in blood
- Type of paper
: Summary in proceedings
Title: Amperometric glucose biosensor based on glucose oxidase
immobilized in electropolzmerized film
- Authors:
- Iveković, Damir
- Milardović, Stjepan (154444)
- Kruhak, Ivan (24133)
- Rumenjak, V
Proceedings title: Sinopsisi XIV. skupa hrvatskih kemičara
Language: hrvatski
Place: Zagreb
Year: 1995
Pages: from 287 to 287
Meeting: XIV. skup hrvatskih kemičara i IV. hrvatski simpoyij o kemiji i tehnologiji makromolekula
Held: from 02/06/95 to 02/08/95
Summary: Amperometric enzymatic sensor for glucose determination was
developed. Glucose oxidase was immobilized in the film using
electropolymerization of pyrol, phenol and N,N-diethylaniline. The
influence of the film thickness and consequently the amount of enzyme on
sensors characteristics was investigated.
Characteristics of individual sensor were investigated using automatic
analyser for glucose determination in blood. Aqueous solutions of glucose
and blood serum with known glucose concentration were used as standard
solutions. Upper linear limit of response was between 20 and 50 mM of
glucose, depending of the sensor used.
Keywords: biosensor for glucose, measurement in blood, immobilization of enzymes using electropolymerization
- Type of paper
: Summary in proceedings
Title: Optical sensor fro continuous monitoring of silver ion
- Authors:
- Murković, Ivana (178963)
- Oehme, Ines
- Ferber, Tomislav
- Mohr, G.J.
- Wolfbeis, Otto S.
Proceedings title: XIV. skup hrvatskih kemičara
Language: engleski
Place: Zagreb
Year: 1995
Pages: from 288 to 288
Meeting: XIV. skup hrvatskih kemičara i IV. hrvatski simpoyij o kemiji i tehnologiji makromolekula
Held: from 02/06/95 to 02/08/95
Summary: A lipophilic dye is used as a silver-sensitive
chromo-ionophore within plasticized PVC membrane. The sensing scheme is
based on a cation-exchange mechanism; silver ions from the aqueous phase
are extracted into the organic phase and complexed by the acridine dye. As
a result of complexation, a proton of the dye molecule is released from
the membrane into the aqueous phase, in order to maintain
electroneutrality. The protonated form of the dye and the silver complex
show different absorbance maxima which are at 680 and 520 nm, respectively.
The signal is detected as a change in absorbance at 680 nm. The response is
fully reversible and, due to high lipophilicity of the dye, very stable.
The measured absorbance response shows a good correlation with
theoretically derived model based on an ion-exchange mechanism. Dynamic
range, detection limits, selectivity, response time, short-term
repeatability, as well as liftime, are presented in details.
Keywords: optical sensor for silver ions, acridine dye, PVC membrane
- Type of paper
: Summary in proceedings
Title: Resolution of global signals using the method of
ratio-pseudo DP polarograms: Determination of p-nitrotoluene and
p-nitroaniline in mixture
- Authors:
- Grabarić, Zorana
- Grabarić, Božidar (14042)
- Esteban, Miquel
- Casassas, Enric
Proceedings title: Sinopsisi XIV. skupa hrvatskih kemičara
Language: engleski
Place: Zagreb
Year: 1995
Pages: from 274 to 274
Meeting: XIV. skup hrvatskih kemičara i IV. hrvatski simpoyij o kemiji i tehnologiji makromolekula
Held: from 02/06/95 to 02/08/95
Summary: Mathematical method for simultaneous polarographic
determination of two components from their mixture is presented. As a model
system p-nitrotoluene and p-nitroaniline is selected. According to Colour
Index both intermediates are used in the production of several hudreds of
dyes, and therefore, their process monitoring is important for quality
assurance of the products. Differential pulse polarograms (DPP) of
individual components, recorded in dimethylformamide using
tetrabuthylammonium iodide as supporting electrolyte, overlap for approx.
80 mV, and, therefore, the simple mathematical method fro resolution of the
global signal is proposed. The method is based on global signal division
with individual signal in time domain. Using the same procedure for sample
and calibration diagrams, well resolved pseudo-DPP are obtained from which
the quantitation of the components in the mixture is obtained. The
influence of different resolution functions on the efficencz of the
resolution of signals obtained
from mixtures having different concentration ratio of p-nitrotoluene and
p-nitroaniline is investigated.
Keywords: resolution of global signals, polarographic determination, p-nitrotoluene, p-nitroaniline, dye intermediates
- Type of paper
: Summary in proceedings
Title: Voltammetric determination of tin in waste waters
- Authors:
- Filipović-Kovačević, Željka
- Sipos, Laszlo (43303)
Proceedings title: Sinopsisi XIV. skupa hrvatskih kemičara
Language: hrvatski
Place: Zagreb
Year: 1995
Pages: from 278 to 278
Meeting: XIV. skup hrvatskih kemičara i IV. hrvatski simpoyij o kemiji i tehnologiji makromolekula
Held: from 02/06/95 to 02/08/95
Summary: Organotin compounds like trimethyltin, tetramethyltin, etc.
are toxic, and therefore they are of special interest in ecology,
especially because tin is used in insecticide production. For classical
electroanalytical determination of small concentrations of tin in samples
of water lead interferes. However, the use of tropolone as complexing agent
and adsorptive cathodic stripping voltammetry give satisfactory results.
Very sensitive electroanalytical method for tin determination in waste
water is developed. Prior to the analytical determination of tin, samples
of waste water are first mineralized. Subsequently using hanging mercury
drop electrode adsorptive accumulation is performed at -0.8 V vs. S.C.E.
during 5-10 min, and finally cathodic stripping voltammograms are recorded
in the potential region between -0.1 and -0.5 V.
Keywords: adsorptive cathodic stripping voltammetry, tin determination, waste water
- Type of paper
: Summary in proceedings
Title: Resolution of global signals using the method of ratio
pseudo-DP polarograms
- Authors:
- Grabarić, Zorana
- Grabarić, Božidar (14042)
- Esteban, Miquel
- Casassas, Enric
Proceedings title: Libro de resumenes, 7.as Jornadas de Analisis Instrumental
Language: engleski
Place: Madrid, Španjolska
Year: 1995
Pages: from ADV06 to ADV06
Meeting: 7.as Jornadas de Analisis Instrumental
Held: from 04/03/95 to 04/06/95
Summary: An efficient and simple resolution method based on signals
ratio in time domain is proposed for differential pulse polarography (DPP)
and related techniques. The ratio pseudo-DPP are obtained dividing the
multianalyte DP polarogram with individual DPP of a single analyte. Using
the same procedure for DPP recorded for calibration diagrams and for DPP of
unknown binarz mixtures, well resolved ratio pseudo-DPP are obtained. The
method is applied to the binary szstem of lead and thallium, having
approximately 70 mV of DPP peaks separation showing considerable
overlapping depending of the medium used and on concentratio ratio od the
two components. The method proposed is able to resolve lead from at least
40-fold excess of thallium, and thallium from at least 20-fold excess of
lead at micromolar concentration range with reproducibilitz betttter than
5%.
Keywords: resolution of global signals, deifferential pulse polarography, lead, thallium, signals ratio method
- Type of paper
: Summary in proceedings
Title: Global electrochemical sensing - An approach to
intelligent chemical sensors
- Authors:
- Grabarić, Božidar (14042)
- Diaz-Cruz, Silvia
- Tauler, Roma
- Esteban, Miquel
- Casassas, Enric
Proceedings title: Book of Abstracts, ESEAC'94, 5th European Conference on Electroanalysis
Language: engleski
Place: Venecija, Italija
Year: 1994
Pages: from 151 to 151
Meeting: ESEAC'94, 5th European Conference on Electroanalysis
Held: from 05/22/94 to 05/26/94
Summary: Carbon fiber ultramicroelectrodes (2r=7 micrometers) with
unmodified and modified surfaces have been used as a global electrochemical
sensors for simultaneous determination of total metal ions (Cu, Pb, Cd, Zn,
Tl, etc.) by different voltammetric perturbation signal programs.
Problems associated with analyte and nonanalyte interferences producing
overlapping or "spoiled" composite signals, have been resolved by
computerized measurement and data acquisition, which, in turn, enabled the
use of powerful chemometric techniques like fast Fourier transform
deconvolution, deconvolution using the family of factor analysis
techniques, etc. Using these techniques a good estimate of individual
analyte concentration or fraction in composite samples has been obtained,
opening, in the near future, the possibility to develop a new generation of
intelligent single chip electrochemical sensors and measuring systems for
global multianalyte detection.
Keywords: ultramicroelectrodes, carbon fiber, resolution of global multianalyte signal, global sensor for metal ions
- Type of paper
: Summary in proceedings
Title: Application of evolving factor analysis to the study by
voltammetric means of complexation equilibria with polyelectrolytes
- Authors:
- Diaz-Cruz, Jose Manuel
- Tauler, Roma
- Grabarić, Božidar (14042)
- Esteban, Miquel
- Casassas, Enric
Proceedings title: Book of Abstracts, 3o Colloquium Chimometricum Mediterraneum
Language: engleski
Place: Bastia, Francuska
Year: 1994
Meeting: 3o Colloquimum Chimometricum Mediterraneum
Held: from 06/07/94 to 06/09/94
Summary: The interaction of trace metals with homofunctional
polyelectrolytes have been studied by voltammetric techniques, and models
have been recently proposed taking into account electrodic adsorption
phenomena or neglecting them. In all cases, rather complicated "hard
modelling" is required where some hypothesis on electrochemical and
chemical model are to be postulated in advance.
The application of "soft modelling" that does not need the initial proposal
of a chemical model is a valuable alternative, mainly in those cases where
the hypothesis are very restrictive or far to be achieved during the
experimental work. So far the application of "soft modelling" on
electrochemical data has not been widespread.
In the present work evolving factor analysis is applied to voltammetric
data of Zn(II) in the presence of polyacrylate and polymethacrylate in
order to provide initial estimation of concentration profiles of species in
equilibrium. These initial estimations are subsequently refined using
recently developed self-modelling curve resolution method. DPP, NPP, RPP
and ASV were used in order to obtain information of the investigated
systems at different metal ion concentration levels.
The species detected bz applying the proposed method are in agreementwith
those assumed in the "hard modelling" and the agreement between the
formation constants evaluated using both approaches is very satisfactory.
Keywords: polyelectrolytes, equilibrium, polyacrylic acid, polymethaacrylic acid, zinc(II) ion, voltammetry, hard modelling, soft modelling, techniques of factor analyisis
- Type of paper
: Summary in proceedings
Title: Silver sensitive optrode membrane based on a lipophilic
acridine dye
- Authors:
- Murković, Ivana (178963)
- Wolfbeis, Otto S.
Proceedings title: Abstracts, 8. Oesterreichische Chemietage
Language: engleski
Place: Graz, Austrija
Year: 1994
Pages: from P114 to P114
Meeting: 8. Oesterreichische Chemietage
Held: from 09/28/94 to 09/30/94
Summary: A lipophilic dye is used as a silver-sensitive
chromo-ionophore within plasticized PVC membrane. The sensing scheme is
based on a cation-exchange mechanism; silver ions from the aqueous phase
are extracted into the organic phase and complexed by the acridine dye. As
a result of complexation, a proton of the dye molecule is released from
the membrane into the aqueous phase, in order to maintain
electroneutrality. The protonated form of the dye and the silver complex
show different absorbance maxima which are at 680 and 520 nm, respectively.
The signal is detected as a change in absorbance at 680 nm. The response is
fully reversible and, due to high lipophilicity of the dye, very stable.
The measured absorbance response shows a good correlation with
theoretically derived model based on an ion-exchange mechanism. Dynamic
range, detection limits, selectivity, response time, short-term
repeatability, as well as liftime, are presented in details.
Keywords: optical sensor for silver ions, acridine dye, PVC membrane
- Type of paper
: Summary in proceedings
Title: Optical sensor for continuous monitoring of silver ion
- Authors:
- Murković, Ivana (178963)
- Oehme, Ines
- Ferber, Tomislav
- Mohr, G.J.
- Wolfbeis, Otto S.
Proceedings title: Symposium Abstracts, 3rd Symposium on Instrumental Analysis
Language: engleski
Place: Pecs, Mađarska
Year: 1995
Pages: from P 26 to P 26
Meeting: 3rd Symposium on Instrumental Analysis
Held: from 05/02/55 to 05/05/55
Summary: A lipophilic dye is used as a silver-sensitive
chromo-ionophore within plasticized PVC membrane. The sensing scheme is
based on a cation-exchange mechanism; silver ions from the aqueous phase
are extracted into the organic phase and complexed by the acridine dye. As
a result of complexation, a proton of the dye molecule is released from
the membrane into the aqueous phase, in order to maintain
electroneutrality. The protonated form of the dye and the silver complex
show different absorbance maxima which are at 680 and 520 nm, respectively.
The signal is detected as a change in absorbance at 680 nm. The response is
fully reversible and, due to high lipophilicity of the dye, very stable.
The measured absorbance response shows a good correlation with
theoretically derived model based on an ion-exchange mechanism. Dynamic
range, detection limits, selectivity, response time, short-term
repeatability, as well as liftime, are presented in details.
Keywords: optical sensor for silver ions, acridine dye, PVC membrane
- Type of paper
: Ph.D.
Title: Study of Ionic Interactions of Metallic Ions with
Substituted Monocarboxylates in Water and Mixed Water/Methanol Solvent
Faculty: Fakultet kemijskog inženjerstva i tehnologije Sveučilište u Zagrebu
Author: KRUHAK IVAN
Date of defense: 06/28/93
Language: hrvatski
Number of pages: 152
Summary: The equilibrium between Co(II), Ni(II), Cu(II), Zn(II),
Cd(II) and Pb(II) ions with propanoate- and hydroxypropanoate have been
investigated in water and water/methanol solutions of volume concentrations
0.40, 0.64, 0.80, 0.89 and 0.98 using constant ionic strength 0.1 M (2 M
for oxopropanoate complexes in water solutions) maintained with addition of
sodium perchlorate. All systems have been investigated using potentiometric
method with glass electrode at 25 oC at different acid-to-salt ratios and
at different metal ion concentrations. Stability constants have been
determined by non-linear least squares fitting and equilibrium constants
independent of the mixed solvent composition have beendetermined. Improved
design of the salt bridge has been proposed, which is very suitable for
potentiometric masurements in small volumes and nonaqueous solvents. Using
this salt bridge superior reproducibility is obtained than by using
conventional salt bridges.
Keywords: stability constants, 2-hydroxypropanoate, 2-oxopropanoate, propanoate, potentiometric method, salt bridge, cobalt, nickel, copper, zinc, cadmium, lead
- Type of paper
: M.A.
Title: Computerized device for measurement of photographic
material density and determination of its properties
Faculty: Fakultet kemijskog inženjerstva i tehnologije Sveučilište u Zagrebu
Author: MILARDOVIĆ STJEPAN
Date of defense: 07/10/91
Language: hrvatski
Number of pages: 109
Summary: Design, construction and application of an on-line
computerized analogue densitometer is described. Numerical and statistical
determination of characteristic parameters of photographic material is
performed. The results obtained in conventional way and those using
computerized system are compared. Samples of x-ray photographic materials
have been analysed.
Keywords: photometry, computerized densitometry, computerized sensitometry, medical x-ray film
- Type of paper
: Mentorship
Title: Study of Ionic Interactions of Metallic Ions with
Substituted Monocarboxylates in Water and Mixed Water/Methanol Solvent
Faculty: Fakultet kemijskog inženjerstva i tehnologije Sveučilište u Zagrebu
Mentor: GRABARIĆ BOŽIDAR
Date of defense: 06/28/93
Number of pages: 152
Author: Kruhak Ivan
Degree level: Ph.D.
- Type of paper
: Mentorship
Title: Computerized Device for Measurement of Photographic
Material Density and Determination of its Properties
Faculty: Fakultet kemijskog inženjerstva i tehnologije Sveučilište u Zagrebu
Mentor: TKALČEC MIHAEL
Date of defense: 07/10/91
Number of pages: 109
Author: Milardović Stjepan
Degree level: M.A.
- Type of paper
: Manuscript
Title: Remediation and Bioremediation of Contaminated Soil. Part
1. Contaminated Sites and Their Remediation
- Authors:
- Košarić, Naim
- Velikonja, Joran (69734)
Language: engleski
Summary: Contamination of the soil as one of the most acute problem
oftoday's live is described. Sources of soil contamination aregiven and the
methods of the analysis of soil are given withspecial attention on sensing
different analytes in contaminatedsoil. Important processes of
bioremediation of contaminated soilare also given.
Keywords: soil contamination, montoring of, boremediation
Other: Rukopis knjige predan izdavaču Springer Verlag,
Berlin-Heildelberg-New York.
- Type of paper
: Manuscript
Title: Remediation and Bioremediation of Contaminated Soil. Part
3. Biological Processes
- Authors:
- Velikonja, Joran (69734)
- Košarić, Naim
Language: engleski
Summary: Principles of bological processes important for monitoring
andbioremediation of contaminated soil are described. Some of
thisprinciples can be used for biosensors development for soilcontamination
monitoring.
Keywords: soil contamination, monitorinh of, biological processes, biosensors
Other: Rukopis knjige predan izdavaču Springer Verlag,
Berlin-Heidelberg-New York
- Type of paper
: Manuscript
Title: Chemical sensing
- Authors:
- Casassas, Enric
- Grabarić, Božidar (14042)
Summary: Chemical sensing monograph. Introduction. General
consideration (Homo sapisens and his environment; analytical proces and
chemical sensing; computers, instruments and sensors). Principles of
chemical sensing (chemical systems; biochemical systems; membranes and
their role in chemical sensing; termodynamical considerations, models and
simulation). Chemical sensors (definitions and classifications;
electrochemical senosrs; optochemical sensors sensors based on other
transducers; technologies for chemical sensors fabrications). Chemometrical
techniques in chemical sensing. Applications of chemical sensors. Future
trends.
Keywords: chemical sensors
- Type of paper
: Invited lecture
Title: Electrochemical sensors and computerized instrumentation
(Božidar Grabarić)
Institution: Karl Franzens University
Year: 1993
- Type of paper
: Invited lecture
Title: Electrochemical sensors and their role in analytical
chemistry (Božidar Grabarić)
Institution: University of Barcelona
Year: 1994
- Type of paper
: Invited lecture
Title: Computerized measurements with electrochemical sensors
(Božidar Grabarić)
Institution: University "Rovira i Virgili"
Year: 1994
- Type of paper
: Invited lecture
Title: Data manipulation incomputerized electrochemical sensoring
(Božidar Grabarić)
Institution: Autonomus University of Barcelona
Year: 1994
- Type of paper
: Invited lecture
Title: Electrochemical biosensors (Božidar Grabarić)
Institution: University of Lleida
Year: 1995
