SVIBOR - Papers - project code: 2-15-124

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Published papers on project 2-15-124


Quoted papers: 3
Other papers: 46
Total: 49


  1. Type of paper: Paper in journal

    Title: Investigations of gibbsite and boehmite dehydroxylation process by means of dynamic thermogravimetry

    Authors:
    Perić, Jelena (36162)
    Krstulović, Ruža (36162)
    Ferić, Tereza (11612)
    Vučak, Marijan (181073)
    Journal: Travaux ICSOBA
    Number: 23
    ISSN: 0350-7548
    Volume: 20
    Year: 1991
    Pages: from 35 to 41
    Number of references: 5
    Language: engleski
    Summary: The process of dehydroxylation of gibbsite and boehmite has been examined by means of nonisothermal TG analysis. Examinations have shown that overall dehydroxylation reaction rate is determined by random formation of new phase centers, and mechanism can be best described by the function f(a)=(1-a)Čn. Influence of temperature is greater than that of process duration, which is characteric for reactions taking place in the kinetic stage, and which is confirmed by the values for the Ea. The average value for the Ea for the the gibbsite dehydroxylation amounts to 122,4 kJ/mol; for boemite dehydroxylation it amounts 216,7 kJ/mol.
    Keywords: Gibbsite, Boehmite, Dehydroxylation, Dinamic Thermogravimetry, Process Mechanism, Process Kinetics.

  2. Type of paper: Paper in journal

    Title: A conceptual design for the treatment of waste water from a printing house zincography

    Authors:
    Perić, Jelena (36162)
    Vučak, Marijan (181073)
    Journal: Kemija u industriji
    Number: 7
    ISSN: 0022-9830
    Volume: 41
    Year: 1992
    Pages: from 269 to 273
    Number of references: 8
    Language: hrvatski
    Summary: Waste water from the etching process was analyzed qualitatively and quantitatively, and the conceptual design for its processing was evaluated on the basis of laboratory tests. For a number of advantages, milk of lime was chosen as neutralization -sedimentation agent. Optimum pH-region was determined to be around 9. Based on the data obtained by laboratory measurementsand the material balance of the etching process, a batch processing plant is proposed, consisting of an oil separator and a neutralizer-settler.
    Keywords: Waste Water, Zincography, Treatment, Neutralization, Precipitation, Zinc.

  3. Type of paper: Paper in journal

    Title: Microcalorimetry in the cement hydration process

    Authors:
    Krstulović, Ruža (36162)
    Ferić, Tereza (11612)
    Krolo, Petar (23832)
    Journal: Periodica Polytechnica
    Number: 3
    ISSN: 0324-583
    Volume: 33
    Year: 1989
    Pages: from 315 to 321
    Number of references: 9
    Language: engleski
    Summary: The paper presents a differential laboratory made microcalorimetric system disigned to enable scientific research into cement hydration .The reproducibility and the statistical processing of the data on the hydration heat were calculated by a computer which provided a basis for calculation of same hydration kinetics parameters.
    Keywords: cement, microcalorimeter, calibration, heat of hydration, statistical processing

  4. Type of paper: Paper in proceedings

    Title: Preparation of calcium carbonate by carbonation of milk of lime

    Authors:
    Perić, Jelena (36162)
    Krstulović, Ruža (36162)
    Vučak, Marijan (181073)
    Ferić, Tereza (11612)
    Editors
    Žižić, Petar
    Proceedings title: Zbornik radova
    Language: hrvatski
    Place: Zagreb
    Year: 1992
    Pages: from 169 to 178
    Meeting: XV Savjetovanje o tehničkim dostignućima i ekološkim rješenjima u proizvodnji cementa i azbest-vlakno cementa
    Held: from 11/05/92 to 11/07/92
    Summary: A process of obtaining the precipitated CaCO3 was carried out by carbonation of suspension of technical lime with a gas mixture CO2 + air. Process took place at the constant gas flow, and stirring rate at different temperatures. Process was traced by measuring the pH of a suspension. Qualitative and quantitative phase analysis of obtained CaCO3 samples were carried out bymeans of Meigen asay, IR-spectroscopy, and X-ray diffraction.
    Keywords: Calcium Carbonate, Carbonation, Milk of Lime, Phase Analysis.

  5. Type of paper: Paper in proceedings

    Title: Precipitation of calcium carbonate from a suspension of lime by a electrical conductivity monitoring

    Authors:
    Perić, Jelena (36162)
    Vučak, Marijan (181073)
    Krstulović, Ruža (36162)
    Editors
    Rojkowski, Zbigniew
    Proceedings title: Proceedings in 2 volumes
    Language: engleski
    Place: Warsaw, Poland
    Year: 1993
    Pages: from 91 to 96
    Meeting: 12th Symposium on Industrial Crystallization
    Held: from 09/21/93 to 09/23/93
    Summary: This report descibes a process of obtaining PCC by means of carbonation of suspension of lime; purity and concentration of raw material was varied, as well as operation temperature at constant mixing rate. Process was monitored through changes in el. conductivity of the suspension. k-t curves have been qualitatively kinetcally interpreted, i.e. they were used to determine the effect of temperature, and gas composition and flow, on carbonation duration. Qualitative phase analysis was determined by means of Meigen assay and X-ray diffraction.
    Keywords: Calcium Carbonate, Carbonation, Suspension, Precipitation, Electrical Conductivity.

  6. Type of paper: Paper in proceedings

    Title: Deterination of kinetic parameters in cement hydration

    Authors:
    Krstulović, Ruža (36162)
    Krolo, Petar (23832)
    Editors
    Mullick, A. K.
    Proceedings title: 9-th International Congress of the Chemistry of Cement
    Language: engleski
    Place: New Delhi, India
    Year: 1992
    Pages: from 31 to 38
    Meeting: 9-th International Congres of the Chemistry of Cement
    Held: from 11/23/92 to 11/28/92
    Summary: The differential microcalorimetric technique was used to study cement hydration in the presence of a superplastificiser as admixtures. This paper introduces a systematic approch to calculation of the important kinetic parameter for the accelerated hydration period. Mathematical anlysis of the hydration kinetics models applied made it possible to get an insight into mechanism of the cement hydration process.
    Keywords: differential microcalorimeter, cement hydration, admixture, kinetic parameres, mechanism
    Other: Izdavač: National Council for Cement and Building Materials(NCB), New Delhi ,India, Vol.IV, Theme III-A

  7. Type of paper: Paper in proceedings

    Title: Tracing the interaction of KMS admixture with the ions from hydrated cement

    Authors:
    Žmikić, Anka (55784)
    Krstulović, Ruža (36162)
    Dabić, Pero
    Krolo, Petar (23832)
    Editors
    Žižić, Petar
    Proceedings title: XV Savjetovanje o tehničkim dostignućima i ekološkim riješenjima u proizvodnji
    Language: hrvatski
    Place: Zagreb
    Year: 1992
    Pages: from 7 to 16
    Meeting: XV Savjetovanje o tehničkim dostignućima i ekološkim rješenjima u proizvodnji cementa i vlakno-cementnih proizvoda
    Held: from 11/05/92 to 11/07/92
    Summary: Interaction of ion species from hydrated cement with theadixture, superplastifier, melamine sulphonic acid condesate withformaldehyde, KMS, was traced by means of conductometric methods. The conductograms of the extract of cement with the admixture indicate that along with adsorption another reaction takes place - that of association of individual species (Ca++, Al+++, Fe+++ ) with the admixture, forming precipitate or acomplex ion.
    Keywords: cement, hydration, conductometry, superplasifier
    Other: Znanstveno - stručni skup!

  8. Type of paper: Paper in proceedings

    Title: Properities and preparation of concrete with the optimum quantity of admixture and strength analysis by non-destructive methods

    Authors:
    Krstulović, Ruža (36162)
    Ferić, Tereza (11612)
    Dabić, Pero
    Žmikić, Anka (55784)
    Krolo, Petar (23832)
    Editors
    Žižić, Petar
    Proceedings title: XV savjetovanje o tehničkim dostignućima i ekološkim riješenjima
    Language: engleski
    Place: Zagreb
    Year: 1992
    Pages: from 302 to 309
    Meeting: XV Savjetovanje o tehničkim dostignućima i ekološkim rješenjima u proizvodnji cementa i vlakno-cementnih proizvoda
    Held: from 07/05/92 to 11/07/92
    Summary: Physical and mechanical properities of concrete, prepared out of PC-30T-45 cement with addition of Izola Be admixture were examined.The behaviour of cement was analyzed when adixture was added, and the optimum quantity to be used in preparation of concrete was determined. The strength of concrete prepared with the optimum quantity of admixture was measured both by means of the standard method - and by non-destructive methods such as ultrasound and sclerometers. The optimum addition of Izola Beadmixture ranges aroud 1.7 % mass, in wich case the strength wasthe highest for all examination times.
    Keywords: cement, admixture, concrete, strength, examination methods

  9. Type of paper: Paper in proceedings

    Title: Influece of Chrysotile asbestos on cement hydration

    Authors:
    Ferić, Tereza (11612)
    Krstulović, Ruža (36162)
    Perić, Jelena (36162)
    Editors
    Žižić, Petar
    Proceedings title: XV savjetovanje o tehničkim dostignućima i ekološkim rijećenjima
    Language: hrvatski
    Place: Zagreb
    Year: 1992
    Pages: from 25 to 33
    Meeting: XV Savjetovanje o tehničkim dostignućima i ekološkim rješenjima u proizvodnji cementa i azbest-vlakno cementa
    Held: from 11/05/92 to 11/07/92
    Summary: Cement hydration was traced by means of hydration heat andadsorption activities of asbestos.The asbestos samples used wereshortfibered,belonging the chrysotile asbestos by theirmineralogical composition.The heat released and the heatdevelopment rate were higher in all samples containig asbestosthan with pure cement paste samples.Examination of adsorption ofcalcium - hidroxide to asbestos fibers points to the asbestossurface activity,wich inproves cement hydration capabilities inthe presence of asbestos.
    Keywords: chrysotile asbestos,cement hydration,calorimetry,adsorption, surface activity
    Other: Znanstveno-stručni skup!

  10. Type of paper: Paper in proceedings

    Title: Precipitation of calcium carbonate by carbon dioxide method

    Authors:
    Perić, Jelena (36162)
    Vučak, Marijan (181073)
    Krstulović, Ruža (36162)
    Editors
    Vincenzini, P.
    Proceedings title: Ceramics: Charting the Future, Vol. B, Proceedings of the 8th CIMTEC
    Language: engleski
    Place: Faenza, Italija
    Year: 1995
    Pages: from 1245 to 1250
    Meeting: Eight Cimtec - World Ceramics Congress
    Held: from 06/28/94 to 07/04/94
    Summary: Milk of lime has been carbonated and CaCO3 precipitated by means of gas mixture, whose composition approximately corresponds to taht of gasses produced by lime kilns. Milk of lime was prepared by slaking quicklime which had been produced by calcination of limestone. The process development was traced by measuring pH values. The samples of PCC were examined for CaCO3 content, particle fineness, and phase composition.
    Keywords: Calcium Carbonate, Calcite, Aragonite, Milk of Lime, Carbonation, Phase Analysis.

  11. Type of paper: Paper in proceedings

    Title: A Study of Degradatin of Cement and Asbestos-Cement Materials

    Authors:
    Krstulović, Ruža (36162)
    Tončić, Damir
    Ferić, Tereza (11612)
    Krolo, Petar (23832)
    Editors
    Fischer, H. B.
    Proceedings title: 12 Internationale Baustofftagung (IBAUSIL), 22-24 Sept.,Weimar
    Language: engleski
    Place: Weimar, Njemačka
    Year: 1994
    Pages: from 328 to 338
    Meeting: 12 Internationale Baustofftagung (IBAUSIL)
    Held: from 09/22/94 to 09/24/94
    Summary: his paper presents a part of results obtained in a study undertaken to improve the quality of AC materials and their service life. Various parameters causing product degradation were examined from the initial stage of the production process up to the final treatment stage.It was concludet that along with attention paid to selection of raw materials and to stability of the production process, special attention should be turend to conditions and methods of post-production treatment of AC products.
    Keywords: Cement, Asbestoscement Materials, degradation, damages, examinations,post-production treatment

  12. Type of paper: Paper in proceedings

    Title: Determination of the C-S-H Phase formed by Pozzolana Reaction of Silica Fume in Hydrated Cement

    Authors:
    Krolo, Petar (23832)
    Krstulović, Ruža (36162)
    Zelić, Jelica (143203)
    Žmikić, Anka (55784)
    Editors
    Jungwirth, Noemi
    Stokić, Vladislav
    Kuzmanić, Ante
    Grisogono, Petar
    Žižić, Petar
    Proceedings title: XVI. savjetovanje o tehnološkim dostignućima i ekološkim rješenjima u proizvodnj
    Language: hrvatski
    Place: Split
    Year: 1995
    ISBN/ISSN: 953-9638-0-8
    Pages: from I-25 to I-33
    Meeting: XVI Savjetovanje o tehnološkim dostignućima i ekološkim rješenjima u proizvodnji cementa i vlakno-cementnih proizvoda
    Held: from 03/09/95 to 03/11/95
    Summary: The effect of the admixture of silica fume on the quantity of hydrates components of the C-S-H phase formed in the water -cement reaction system was examined. The Ca(OH)2 content, i.e. the quantity of water bound to Ca(OH)2 was used to determine the quantity of water bound to hydrates in the hydraulic ( C-S-H ) phase. The lowest values of the Ca(OH)2 content correspond to the highest content of the C-S-H phase formed during cement hydration and pozzolana reaction.
    Keywords: Silica Fume, PC pastes, CH, CSH phase, Thermogravimetry

  13. Type of paper: Paper in proceedings

    Title: Study of Interaction of KMS and KNS Admixtures with Ions from Hydrated Cement

    Authors:
    Žmikić, Anka (55784)
    Krstulović, Ruža (36162)
    Krolo, Petar (23832)
    Editors
    Jungwirth, Noemi
    Stokić, Vladislav
    Kuzmanić, Ante
    Grisogono, Petar
    Žižić, Petar
    Proceedings title: XVI. Savjetovanje o tehn. dostignućima i ekološkim rješenjima u priz. cementa i
    Language: hrvatski
    Place: Split
    Year: 1995
    Pages: from I-73 to I-80
    Meeting: XVI Savjetovanje o tehnološkim dostignućima i ekološkim rješenjima u proizvodnji cementa i vlakno-cementnih proizvoda
    Held: from 03/09/95 to 03/11/95
    Summary: Conductometrical and UV- spectrophotometrical methods were used to trace the interaction between the admixtures: KMS and KNS, respectively, and Ca2+, Al3+, Fe3+, AlO2-, H3O+ and OH- ions. The conductrograms and apsorption electron spectra provided a basis for a discussion of the interaction of hydrated or complex ions with the superplasticizers used.
    Keywords: Admixtures, Interaction, electrolytic solutions, Spectrophotometry, Conduction

  14. Type of paper: Summary in proceedings

    Title: A solution of treatment of waste water from a zincography of printer's

    Authors:
    Perić, Jelena (36162)
    Vučak, Marijan (181073)
    Proceedings title: Abstracts
    Language: engleski
    Place: Zagreb
    Year: 1991
    Pages: from 361 to 361
    Meeting: Symposium Ecologically Rational Development of Chemical Technologies
    Held: from 02/14/91 to 02/15/91
    Summary: Waste water from the etching process was analyzed qualitatively and quantitatively, and the conceptual design for its processing was evaluated on the basis of laboratory tests.
    Keywords: Waste Water, Zincography, Tretment, Neutralization, Precipitation, Zinc.

  15. Type of paper: Summary in proceedings

    Title: Kinetics of gibbsite dehydroxylation process in non-isothermal conditions

    Authors:
    Perić, Jelena (36162)
    Krstulović, Ruža (36162)
    Ferić, Tereza (11612)
    Dabić, Pero
    Proceedings title: Sinopsisi
    Language: hrvatski
    Place: Zagreb
    Year: 1991
    Pages: from 235 to 235
    Meeting: XII. Sastanak kemičara Hrvatske
    Held: from 02/11/91 to 02/13/91
    Summary: The process of dehydroxylation of gibbsite has been examined by means of nonisothermal TG analysis.
    Keywords: Gibbsite, Dehydroxylation, Nonisothermal TG, Process Mechanism, Process Kinetics.

  16. Type of paper: Summary in proceedings

    Title: Examination of phase transformation of aragonite into calcite by means of DSC analysis

    Authors:
    Perić, Jelena (36162)
    Krstulović, Ruža (36162)
    Ferić, Tereza (11612)
    Vučak, Marijan (181073)
    Dabić, Pero
    Proceedings title: Sinopsisi radova
    Language: hrvatski
    Place: Sarajevo, Jugoslavija
    Year: 1991
    ISBN/ISSN: 0367-4444
    Pages: from 133 to 133
    Meeting: Šesti jugoslavenski simpozijum analitičke hemije
    Held: from 09/30/91 to 10/02/91
    Summary: In examined samples of CaCO3, sinthesized in laboratory and industrial samples, Phase analysis of CaCO3 samples was carried out by means of X-ray diffraction. Transformation of the aragonite modification into the stable calcite structure was traced by means of DSC analysis. A mathematical analysis ofe xperimental DSC curves defined mechanism and the kinetics of the process.
    Keywords: Aragonite, Calcite, Calcium Carbonate, Phase Transition, DSC Analysis, Process Kinetics, Process Mechanism.

  17. Type of paper: Summary in proceedings

    Title: Examination of dehydroxylation process of gibbsite into boehmite by means of DSC anlysis

    Authors:
    Perić, Jelena (36162)
    Krstulović, Ruža (36162)
    Ferić, Tereza (11612)
    Vučak, Marijan (181073)
    Editors
    Bardossy, Gy.
    Proceedings title: Abstracts
    Language: engleski
    Place: Budapest, Hungary
    Year: 1992
    Pages: from 82 to 82
    Meeting: 7th International Congress of ICSOBA
    Held: from 06/22/92 to 06/26/92
    Summary: Dehydroxylation of gibbsite into boehmite was traced by means of DSC analysis. A mathematical analysis of experimental DSC curves defined the mechanism and the kinetics of gibbsite dehydroxylation process.
    Keywords: Gibbsite, Boehmite, Dehydroxylation, DSC Analysis, Process Mechanism, Process Kinetics.

  18. Type of paper: Summary in proceedings

    Title: Precipitation of calcium carbonate by carbonation of milk of lime

    Authors:
    Perić, Jelena (36162)
    Vučak, Marijan (181073)
    Krstulović, Ruža (36162)
    Ferić, Tereza (11612)
    Proceedings title: Sinopsisi
    Language: hrvatski
    Place: Zagreb
    Year: 1993
    Pages: from 359 to 359
    Meeting: XIII. Skup hrvatskih kemičara
    Held: from 02/08/93 to 02/10/93
    Summary: This report describes process of obtaining PCC by means of carbonation of suspension of lime; concentration and gas flow were varied as well as operation temperature. Process was monitored through changes in el. conductivity of the suspension. k-t have been qualitatively kinetically interpreted. The content of CaCO3 and the qualitative phase analysis of samples synthesized was determined.
    Keywords: Calcium Carbonate, Carbonation, Suspension, Precipitation, Electrical Conductivity.

  19. Type of paper: Summary in proceedings

    Title: Adsorption of calcium hydroxide on polyacrylnitrile, cellulose and chrysotile fibers

    Authors:
    Ferić, Tereza (11612)
    Krstulović, Ruža (36162)
    Perić, Jelena (36162)
    Vučak, Marijan (181073)
    Proceedings title: Sinopsisi
    Language: hrvatski
    Place: Zagreb
    Year: 1993
    Pages: from 345 to 345
    Meeting: XII. Skup hrvatskih kemičara
    Held: from 02/08/93 to 02/10/93
    Summary: This paper presents results obtained for surface activity in two types of polyacrylnitrile fibers and treated celluloze fibers as compared to chrysotile asbestos, by determination of adsorption of calcium hydroxide to the fibers. Fibers examined have a surface activity similar to that of asbestos fibers, and may be expected to have a similar effect on cement hydration.
    Keywords: Adsorption, Calcium Hydroxide, Asbestos, Polyacrylonitrile Fibers, Chrysotile.

  20. Type of paper: Summary in proceedings

    Title: Examination of interaction of different ions from synthetic solution with admixtures to cement

    Authors:
    Žmikić, Anka (55784)
    Krstulović, Ruža (36162)
    Dabić, Pero
    Krolo, Petar (23832)
    Proceedings title: Šesti jugoslovevenski simpozijum analitičke hemije
    Language: hrvatski
    Place: Sarajevo, Jugoslavija
    Year: 1991
    ISBN/ISSN: 0367-4444
    Pages: from 132 to 132
    Meeting: Šesti jugoslovenski simpozijum analitičke kemije
    Held: from 09/30/91 to 10/02/91
    Summary: The KMS and KNS admixtures adsorb on the particles of hydrated cement. Ionic species ineract in the solution with the admixtures. Conuctometrictal methods examined the interaction of the ionicspecies CaCl2, AlCl3, FeCl3, Ca(OH)2 and NaAlO2 with the admixtures. Conductograms obtained explain the interaction of various ionic species with the admixtures.
    Keywords: superplastificiser, KMS, KNS, electrolyte solution, conductometry, ionic reactions

  21. Type of paper: Summary in proceedings

    Title: Microclorimetry in study of the kinetic heterogenous cement - water reaction

    Authors:
    Krstulović, Ruža (36162)
    Ferić, Tereza (11612)
    Dabić, Pero
    Krolo, Petar (23832)
    Proceedings title: XII sastanak kemičara Hrvatske
    Language: hrvatski
    Place: Zagreb
    Year: 1991
    Pages: from 236 to 236
    Meeting: XII. Sastanak kemičara Hrvatske
    Held: from 02/11/91 to 02/13/91
    Summary: Differential microcalorimetry was used to monitor cement hydration in the presence of superplastificiser. The kinetic parameters examined were shown to depend on the quantity of admixture added which therefore affects the reaction rate.
    Keywords: differential microcalorimeter, cement, superplastifizer, hydration, kineticparameters

  22. Type of paper: Summary in proceedings

    Title: Conductometric tracing the interaction ions from hydrated cement with admixture KNS

    Authors:
    Žmikić, Anka (55784)
    Krstulović, Ruža (36162)
    Dabić, Pero
    Krolo, Petar (23832)
    Proceedings title: XIII skup hrvatskih kemičara
    Language: hrvatski
    Place: Zagreb
    Year: 1993
    Pages: from 361 to 361
    Meeting: XIII. Skup hrvatskih kemičara
    Held: from 02/08/93 to 02/10/93
    Summary: The effect of the KNS superplasticizer on cement hydration has been examined. The specific conductivity of the adixture in the cement extract, w(%) = 0.1 - 0.15 % was measured by conductomertrical methods before and after adsorption. It wasconcluded that ionic species of hydrated cement interacted with the adixture.
    Keywords: cement, KNS admixture, hydration, conductometry, interaction of ionic species

  23. Type of paper: Summary in proceedings

    Title: Superplasticiser activity of melamin-formaldehyde admixture in the cement-water reacting system

    Authors:
    Krstulović, Ruža (36162)
    Dabić, Pero
    Ferić, Tereza (11612)
    Žmikić, Anka (55784)
    Krolo, Petar (23832)
    Proceedings title: XIII Skup hrvatskih kemičara
    Language: hrvatski
    Place: Zagreb
    Year: 1993
    Pages: from 362 to 362
    Meeting: XIII. Skup hrvatskih kemičara
    Held: from 02/08/93 to 02/10/93
    Summary: Microcalorimetrical methods were used to examine the efffect of the "Melment" (KMS) superplastciser admixture. The effect of the KMS on induction duration was determined as well as its optimum quantity added to cement. The results were in accord with strenghts obtained in concrete and in comparison to non-destructive methods.
    Keywords: cement, "Melment" adixture, hydration,microcalorimetry, optimum admixture quantity, concrete strength

  24. Type of paper: Summary in proceedings

    Title: High Purity Precipitated Calcium Carbonate

    Authors:
    Perić, Jelena (36162)
    Vučak, Marijan (181073)
    Krstulović, Ruža (36162)
    Dabić, Pero
    Proceedings title: Sinopsisi
    Language: hrvatski
    Place: Zagreb
    Year: 1995
    Pages: from A62 to A62
    Meeting: XIV. Skup hrvatskih kemičara
    Held: from 02/06/95 to 02/08/95
    Summary: In this paper the influence of temperature on the carbonation process of calcium nitrate solution in monoethanolamine and product properties have been examined.
    Keywords: Precipitation, High purity Calcium Carbonate, Carbonation, Monoethanolamine.

  25. Type of paper: Summary in proceedings

    Title: Precipitation of Calcium Carbonate in Calcium Nitrate and Monoethanolamine Solution

    Authors:
    Vučak, Marijan (181073)
    Perić, Jelena (36162)
    Krstulović, Ruža (36162)
    Proceedings title: ICCGXI-Abstracts
    Language: engleski
    Place: The Hague, The Netherlands
    Year: 1995
    Pages: from 410 to 410
    Meeting: The Eleventh International Conference on Crystal Growth
    Held: from 06/18/95 to 06/23/95
    Summary: Extra pure precipitated calcium carbonate was obtained in laboratory by carbonation of calcium nitrate and monoethanolamine solution. Process parameters and product properties have been discussed.
    Keywords: Precipitation, Crystallization, Extra Pure Calcium Carbonate, Carbonation, Morphology.

  26. Type of paper: Summary in proceedings

    Title: Characterization of Crystal Morphology by Image Analysis: Application to Calcium Carbonate and Various Oxalates

    Authors:
    Vučak, Marijan (181073)
    Vivier, H.
    Pons, M.N.
    Proceedings title: Abstracts
    Language: engleski
    Place: Nancy, Francuska
    Year: 1995
    Pages: from 6 to 7
    Meeting: 26th Seminar: Nancy-Karlsruhe-Enschede
    Held: from 06/23/95 to 06/25/95
    Summary: Caracterization of crystal shapes has been carried out using image analysis of precipitated calcium carbonate and various Me oxalate crystals.
    Keywords: Calcium Carbonate, Me Oxalates, Crystal Shapes, Morphology, Image Analysis.

  27. Type of paper: Summary in proceedings

    Title: The effect of silica fume on formation of C-S-H phase by determination of hydrated water in portlad cement pastes

    Authors:
    Krolo, Petar (23832)
    Krstulović, Ruža (36162)
    Zelić, Jelica (143203)
    Žmikić, Anka (55784)
    Proceedings title: Sinopsisi
    Language: hrvatski
    Place: Zagreb
    Year: 1995
    Pages: from g361 to g361
    Meeting: XIV. Skup hrvatskih kemičara
    Held: from 02/06/95 to 02/08/95
    Summary: The TG analysis has been used to examine the effect of different amounts of silica fume admixtureon formati on ofrmation of CSH phases in the cement- water reaction system, through determinatin of the content of water bound during hydration. the silica fume has been proved to affect the content on non-bound Ca(OH)2 and thereby the content of CSH phases formed by the puzzolana reaction.
    Keywords: C-S-H phase, hydrated water, silica fume, pozzolana reaction

  28. Type of paper: Summary in proceedings

    Title: The determination of calcium hydroxide in cement pastes by means DTA

    Authors:
    Ferić, Tereza (11612)
    Krstulović, Ruža (36162)
    Perić, Jelena (36162)
    Krolo, Petar (23832)
    Proceedings title: Rinopsisi radova
    Language: hrvatski
    Place: Sarajevo, Jugoslavija
    Year: 1991
    ISBN/ISSN: ISSN0367-4444
    Pages: from 134 to 134
    Meeting: Šesti jugoslovenski simpozijum analitičke kemije
    Held: from 09/30/91 to 10/02/91
    Summary: samples has been prepared by mixing industrial cement and water at W/C00.476 and addition of 12.5% asbestos, with different hydration durations. The surface under the DTA curves was determined in order to calculate the quantity of Ca(OH)2 for the period up to five months. The results indicate that the DTA method is suitable for determinatin of Ca(OH)2 in the cement-water- admixtures system.
    Keywords: Hydration, thermal-analysis, calcium- hydroxide, cement paste

  29. Type of paper: Ph.D.

    Title: Phenomena in Cement Hydation in the Presence of Asbestos
    Faculty: Tehnološki fakultet Sveučilište u Splitu
    Author: FERIĆ TEREZA
    Date of defense: 06/13/91
    Language: hrvatski
    Number of pages: 225
    Summary: The influence of asbestos on hydration process was studied in the system cement-asbestos-water. The samples were prepared in proportions similar to those in industrial mixtures.The hydration was determined by mesuments of hydration heat (calorimetry) and development of Ca(OH)2. It was proved that hydration mechanism in asbestos cement is similar to that in pure cement regardless of asbestos sort and type and depends on adsorption capacity of asbestos, which has approx 10 EXP 18 active sites per sqm of surface, which explains the influence of asbestos on cement hydration intensity. The methodology used can be applied to other fiber materials and their effect on cement hydration.
    Keywords: Cement , Asbestos fibers , Hydration , calorimetry , TG , DTA , adsorption , mechanism


  30. Type of paper: M.A.

    Title: Process for obtaining precipitated calcium carbonate by carbonation of milk of lime
    Faculty: Fakultet kemijskog inženjerstva i tehnologije Sveučilište u Zagrebu
    Author: VUČAK MARIJAN
    Date of defense: 12/03/93
    Language: hrvatski
    Number of pages: 129
    Summary: Precipitated CaCO3 was obtained in laboratory by carbonation of milk of lime with CO2; purity and concentration of Ca(OH)2 were varied, as well as gas composition and flow, and temperature. The process took place at a constant mixing rate. El. conductivity has been used as a parameter for tracing the carbonation process. An analysis of the shape and the flow of k-t curves provided an insight into possibilities of formation of the precipitate and its phase transformations during carbonation, and process kinetics. The precipitated CaCO3 was examined for CaCO3 content, phase composition, apparent density in a condensed state, and for particle size.
    Keywords: Amorphous CaCO3, Aragonite, Calcite, Calcium Carbonate, Carbonation of Milk of Lime, Precipitation, Vaterite.


  31. Type of paper: M.A.

    Title: A MATHEMATICAL MODEL FOR DETERMINING THE OPTIMUM ASBESTOS MIXTURES FOR ASBESTOS-CEMENT MATERIALS
    Faculty: Tehnološki fakultet Sveučilište u Splitu
    Date of defense: 01/18/91
    Language: hrvatski
    Number of pages: 144
    Summary: The aim was to determine the optimum combination of mixtures to be used in asbestos industry, and satisfy the need for engine productivity, system economy, and the finished product quality. Each asbestos type was correlated to the referent one. A redefinid linear programming model was used to solve this system. It was proved that only the optimum asbestos content satisfies the aims set. Asbestos fibers surplus does not improve the quality of asbestos cement products.
    Keywords: Asbestos, optimum mixture, calculation, computer programming, correlations


  32. Type of paper: M.A.

    Title: Kinetic analysis of cement hydration
    Faculty: Tehnološki fakultet Sveučilište u Splitu
    Author: DABIĆ PERO
    Date of defense: 06/19/95
    Language: hrvatski
    Number of pages: 103
    Summary: This thesis the experimental and mathematical approach to solving the cement hydration kinetics with the main objective of development and application of such a mathematical model that would best describe individual stages of the process as a whole. The matherial used was the industrial Portland cement PC-55, alit, and the PC-30z-45s cement with addition of slag, to which four different types of commercial admixtures were added. the model assumed that all tree stages take place simultaneously; bat individual hydration stages are governed by the slowest process. when alfa was inserted in the appropriate kinetic equations for individual process stages, expression for nucleation and growth (NR) were obtained, as well phase-boundary (I) and the diffusion process (D).When adixtures were introduced into cement the changes in kinetic parameters were observed, in the process intesity relative to the admixture type. The mathematical model developed can be show the hydration kinetics events quantitatively and in greater detail, based on the data on heat development. It is necessary to link task solution in kinetic analysis by all groups with the computer by means of the program support, which has been done in this work.
    Keywords: Portland cement, admixture, hydration process,microcalorimeter, Hydration heat, kinetic anlysis, mathematical modelling, program pacages, Gwbasic, Qbasic, personal computer


  33. Type of paper: Mentorship

    Title: Process for obtaining precipitated calcium carbonate by carbonation of milk of lime
    Faculty: Fakultet kemijskog inženjerstva i tehnologije Sveučilište u Zagrebu
    Mentor: PERIĆ JELENA
    Date of defense: 12/03/93
    Number of pages: 129
    Author: Vučak Magistar znanosti, zn. novak Marijan
    Degree level: M.A.


  34. Type of paper: Mentorship

    Title: Phenomena in Cement Hydation in the Presence of Asbestos
    Faculty: Tehnološki fakultet Sveučilište u Splitu
    Mentor: KRSTULOVIĆ RUŽA
    Date of defense: 06/13/91
    Number of pages: 225
    Author: Ferić Doktor znanosti, ZA Tereza
    Degree level: Ph.D.


  35. Type of paper: Mentorship

    Title: A MATHEMATICAL MODEL FOR DETERMINING THE OPTIMUM ASBESTOS MIXTURES FOR ASBESTOS - CEMENT MATERIALS
    Faculty: Tehnološki fakultet Sveučilište u Splitu
    Mentor: KRSTULOVIĆ RUŽA
    Date of defense: 01/18/91
    Number of pages: 144
    Author: Milošević magistar Velimir
    Degree level: M.A.


  36. Type of paper: Mentorship

    Title: Kinetic analysis of cement hydration
    Faculty: Tehnološki fakultet Sveučilište u Splitu
    Mentor: KRSTULOVIĆ RUŽA
    Date of defense: 06/19/95
    Number of pages: 103
    Author: Dabić Zn. novak Pero
    Degree level: M.A.


  37. Type of paper: Survey/Study

    Title: Technical and technological Solution for Waste Water Treatment of the Zinc Plateing Plant of Poliscom Split

    Authors:
    Perić, Jelena (36162)
    Krolo, Petar (23832)
    Zelić, Jelica (143203)
    Vučak, Marijan (181073)
    Dabić, Pero
    Beroš, Ana
    Ordering party: Poliscom-Split
    Institution depot: Tehnološki fakultet Sveučilišta u Splitu
    Year: 1994
    Number of pages: 29
    Language: hrvatski
    Summary: The laboratory analysis of waste water from chemical treatment of metal objects prior to zinc-plateing in the Poliscom-Split firm helped determine the optimum conditions for carrying out oxidation, neutralization and precipitation of Fe(OH)3 and Zn(OH)2. Based on this examinations a technical and technological solution has been proposed for waste water treatment before its draining into the sewage system. The solution will provide for satisfactory degree of operation efficiency, as well as for lower costs of treatment with the existing equipment by means of energy-saving and by reducing the operating hours of the equipment.
    Keywords: Waste water, Zinc Plateing, Neutralization, Oxidation, Precipitation, Metal Hydroxides.

  38. Type of paper: Manuscript

    Title: Investigation of dehydroxylation process of gibbsite into boehmite by DSC analysis

    Authors:
    Perić, Jelena (36162)
    Krstulović, Ruža (36162)
    Vučak, Marijan (181073)
    Language: engleski
    Summary: Dehydroxylation of gibbsite into boehmite was traced by means of DSC analysis. Samples were analyzed by DSC under non isothermal conditions in the temperature range 453-673 K at heating rates from 2,5 to 20,0 K/min. A mathematical analysis of experimental DSC curves defined the mechanism and the kinetics of gibbsite dehydroxylation process. The values of Ea for the first stage of gibbsite dehydroxylation in temerature range 453-673 K amounts to 132,92 - 142,26 kJ/mol.
    Keywords: Dehydroxylation, Gibbsite, Boehmite, DSC Analysis, Process Kinetics, Activation Energy.
    Other: Rad je u tisku (Časopis: Journal of Thermal Analysis).

  39. Type of paper: Manuscript

    Title: Adsorption of calcium hydroxide on polyacrylonitrile, cellulose and chrysotile fibers

    Authors:
    Ferić, Tereza (11612)
    Krstulović, Ruža (36162)
    Perić, Jelena (36162)
    Vučak, Marijan (181073)
    Language: engleski
    Summary: This paper presents results obtained for surface activity in two types of polyacrylnitrile fibers and treated celluloze fibers as compared to chrysotile asbestos, by determination of adsorption of calcium hydroxide to the fibers. Fibers examined have surface activity similar to that of asbestos fibers, and may be expected to have a similar effect on cement hydration.
    Keywords: Adsorption, Calcium Hydroxide, Asbestos, Polyacrylonitrile Fibers, Chrysotile.
    Other: Rad je u tisku (Časopis: Cement-Kalk-Gips).

  40. Type of paper: Manuscript

    Title: Position of a young research worker at the university

    Authors:
    Vučak, Marijan (181073)
    Dabić, Pero
    Language: engleski
    Summary: In this report, problematics related to young research scientist position and their participating in the scientific project have been discussed.
    Keywords: Ceramic Engineering, Ceramic Technology.
    Other: Rad prezentiran na "Second European Conferenceof Higher Educational Institutions in Ceramics (EUROFORUM'94), 24.04.1994- do 26.04.1994., H‹hr-Grenzhausen (Njemačka).

  41. Type of paper: Manuscript

    Title: Effect of chrysotile asbestos on cement hydration

    Authors:
    Ferić, Tereza (11612)
    Krstulović, Ruža (36162)
    Perić, Jelena (36162)
    Krolo, Petar (23832)
    Language: engleski
    Summary: Hydration of cement in the presence of asbestos was traced by means of hydration heat and adsorption capabilities of asbestos. Hydration heat was determined calorimetrically by means of spherical thermos flasks; adsorption capability of asbestos fibers was determined relative to Ca(OH)2. Hydration heat development was intesified in the presence of asbestos. The results obtained for adsorption have showed that asbestos surface is active and the isotherms obtained are multistep ones and indicate formation of two layers of adsorbate. Adsorption capabilities of asbestos intensify cement hydration.
    Keywords: Cement, Asbestos, Hydration, Adsorption, Chrysotile, Hydration Heat.
    Other: Rad u tisku (časopis: "Cement and Concrete Composites").

  42. Type of paper: Manuscript

    Title: A mathematical model for determination of optimum asbestos mixers for asbestos-cement material

    Authors:
    Milošević, Velimir
    Tončić, Damir
    Krstulović, Ruža (36162)
    Language: engleski
    Summary: The optimum mixture of asbestos types for asbestos-cementproducts was mathematically modelled by redefined linearprogramming model ritten in Turbo Pascal 5.5 for an IBMcompatibile PC.Different mixtures were examined and used inindustrial experiments.Comparison of mathematically extimatedvalues for expected finished product strength with experimentalresults (7,28 days) showd very good correspondece and therebyconfirmen the validity of the method.
    Keywords: mathematical modelling,asbest mixture,program product,Turbo Pascal 5.5,industrial experiments,comparison of the method with experimental data
    Other: Predano za tiasak u časopis: Cement and Concrete Composites

  43. Type of paper: Manuscript

    Title: Phase Transformation of Calcium Carbonate Polymorphs

    Authors:
    Perić, Jelena (36162)
    Vučak, Marijan (181073)
    Krstulović, Ruža (36162)
    Brečević, Ljerka
    Kralj, Damir
    Language: engleski
    Summary: The phase composition of mineral aragonite ans sythetic vaterite samples was determined qualitatively by using IR-spectroscopy and XRD analysis. The transformation of aragonite and vaterite into the stable modification calcite, was folowed using DSC analysis. In order to determine the kinetics and mechanisms of these phase transformations, a number of experimental DSC curves were elaborated mathematicaly and the stationary point theory was applied. The activation energy, Ea, and the enthalpy, dH, were found to be, respectively, 234.5 +- 5.6 kJ/mol and 122 J/g for the phase transformation aragonite to calcite, and 252.8 +- 48.7 kJ/mol and -21.2 J/g for the vaterite to calcite transformation.
    Keywords: Phase Transformation, Calcium Carbonate, Vaterite, aragonite, Calcite, Kinetics, Stationary Point Theory.
    Other: Thermochimica Acta, u tisku.

  44. Type of paper: Manuscript

    Title: Precipitation of Calcium Carbonate in a Calcium Nitrate and Monoethanolamine Solution

    Authors:
    Vučak, Marijan (181073)
    Perić, Jelena (36162)
    Krstulović, Ruža (36162)
    Language: engleski
    Summary: High purity precipitated calcium carbonate has been produced in laboratory by carbonation of a solution of calcium nitrate and monoethanolamine. The process was traced by measurements of the change in Ca concentration and in el. conductivity of the solution. The k-t and cCa-t curves were analyzed to determine the effect of temperature and concentration of carbon(IV) oxide on the process of carbonation. The samples obtained were mainly of aragonite and vaterite crystal modifications with traces of calcite. The relationship between the mineralogical composition and particle size (morphology) and operating conditions was examined as well.
    Keywords: Precipitation, Crystallization, High Purity Calcium Carbonate, Carbonation, Morphology.

  45. Type of paper: Manuscript

    Title: studies of Cement - water- admixtures reaction system

    Authors:
    Krstulović, Ruža (36162)
    Language: engleski
    Summary: This report describes examinations carried out in our laboratory so far-which will be continued with the cement - water - admixture reaction system. The most important issues are discussed as well confirmations of results achieved over mani years of research into the effect of admixtures on the cement hydration process. The principles of research aimed at understandig hydration both qualitatively and quantitatively are listed.
    Keywords: Cement, admixture, hydration process, methodological - method examinations, kinetic analysis, interaction

  46. Type of paper: Other

    Title: On the mechamism of inhibitive action of Na-diethyldithio carbamate

    Authors:
    Aljinović, Ljiljana (362)
    Šmith, Mario (149441)
    Žmikić, Anka (55784)
    Type of work: Sažetak u zborniku (vezano za projekt 2-15-122)
    Language: hrvatski
    Summary: The inhibitive properties of Na-diethyldithiocarbamate (NaDDTC) for Cu Ni10 Fe alloy corrosion in sea water have been investigated by means of electrochemical methods and surface analytical technique (AES). The presence of all elements from organic molecule on the alloy surface has been estabilished after polarization in agresive media. Besides, the influence of NaDDTC on the shape and position of polarization curves has been estabilished. The various reaction posibilities of -DDTC anion as well as its parts of decomposition after polarization have been discussed.
    Keywords: Inhibitor, cunifer alloy, thiocarbamate
    Other: Rad je vezan uz projekt 2-15-122.


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