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Papers quoted in Current Contents on project 1-07-190

Quoted papers: 53
Other papers: 78
Total: 131

Title:

Authors:: Čižmek, Ankica (42414); Komunjer, Ljepša (21916); Subotić, Boris (45364); Široki, Marija (47105); Rončević, Sanda (164890)

Journal: Zeolites
Number: 3
ISSN: 0144-2449
Volume: 11
Year: 1991
Pages: from 258 to 264
Number of references: 47
Language: engleski
Summary: Kinetics of dissolution of zeolite A in 1 and 2 M NaOH solutions,at 338, 343, 348 and 353 K, were studied by different methodssuch as chemical analysis, phase analysis, particle sizedistribution analysis and determination of the stage ofpolycondensation of silicate anions in the liquid phase. Theresults obtained were analyzed and discussed in accordance with known theories of dissolution, taking into account thechemical and structural characteristics of zeolites.
Keywords: zeolite A, dissolution, mechanism, kinetics

Title:

Authors:: Aiello, Rosario; Crea, Fortunato; Nastro, Alfonso; Subotić, Boris (45364); Testa, Flaviano

Journal: Zeolites
Number: 8
ISSN: 0144-2449
Volume: 11
Year: 1991
Pages: from 767 to 775
Number of references: 41
Language: engleski
Summary: The influence of type of alkali cations (Li, Na, K) on theproperties of aluminosilicate gels were studied by chemical andthermal analysis. Analysis of kinetic of dehydration of gels aswell as hydrothremal reatment of the gels confirmed the role ofsodium ion as a "structure-forming" cation and revealed thatsodium ions cause the formation of structural subunits inside thegel matrix.
Keywords: Alumosilicate gel, chemical properties, thermal properties, structure

Title:

Authors:: Goleme, Gianni; Nastro, Alfonso; Nagy, Janos Bela; Subotić, Boris (45364); Crea, Fortunato; Aiello, Rosario

Journal: Zeolites
Number: 8
ISSN: 0144-2449
Volume: 11
Year: 1991
Pages: from 776 to 783
Number of references: 33
Language: engleski
Summary: The autocatalytic model of nucleation is used to study thecrystallization of ZSM-5 in five systems differing in the Alcontent of the starting gel. The crystallization kinetics and thenucleation kinetics are examined by SEM and x-ray diffraction.Experimental evidence is presented for the validity of theautocalytic nucleation model. The two kinds of nucleation (heterogeneous and autocatalytic) processes adequately explainall the crystallization curves.
Keywords: Zeolite ZSM-5, autocatalytic nucleation, crystal growth, nucleation kinetics

Title:

Authors:: Čižmek, Ankica (42414); Komunjer, Ljepša (21916); Subotić, Boris (45364); Široki, Marija (47105); Rončević, Sanda (164890)

Journal: Zeolites
Number: 8
ISSN: 0141-2449
Volume: 11
Year: 1991
Pages: from 810 to 815
Number of references: 11
Language: engleski
Summary: Kinetics of dissolution of zeolite X in 2 M NaOH solutions, at338, 343, 348 and 353 K, were studied by different methods suchas chemical analysis, phase analysis, particle size distributionanalysis and the determine of the stage of polycondensation ofsilicate anions in the liquid phase. The results obtained wereanalyzed and discussed in accordance with the model of growth anddissolution proposed by Davies and Jones, taking into account thechemical and structural characteristics of zeolites.
Keywords: Zeolite X, dissolution, mechanism, kinetics

Title:

Authors:: Bronić, Josip (117985); Subotić, Boris (45364)

Journal: Journal of Radioanalitical and Nuclear Chemistry
Number: 2
ISSN: 0263-5731
Volume: 152
Year: 1991
Pages: from 359 to 371
Number of references: 35
Language: engleski
Summary: The analysis of the change in the concentration of cesium ions inthe solution and distribution of cesium ions in the columnfillings (granulated zeolites), after passing (with differentflow rates) 0.1, 0.05 and 0.01 M solutions of cesium nitratethrough the columns filled with various granulated zeolites (A,X, synthetic mordenite) was performed. On the basis of thisstudy, the conditions for the most efficient removal of cesium ions from solutions have been discussed.
Keywords: Cesium radioisotopes, removal, ionic excange radioactive liquids, granulated zeolites

Title:

Authors:: Čižmek, Ankica (42414); Komunjer, Ljepša (21916); Subotić, Boris (45364); Široki, Marija (47105); Rončević, Sanda (164890)

Journal: Zeolites
Number: 2
ISSN: 0144-2449
Volume: 12
Year: 1992
Pages: from 190 to 196
Number of references: 13
Language: engleski
Summary: Kinetics of dissolution of synthetic mordenite in 1 M NaOHsolutions, at 338, 343, 348 and 353 K, were studied by variousexperimental techniques such as ICP spectroscopy, FTIRspectroscopy, x-ray diffractometry and particle size distributionmeasurements. The results obtained were analyzed and discussed inaccordance with the model of growth and dissolution proposed byDavies and Jones, taking into account the chemical and structuralcharacteristics of synthetic mordenite.
Keywords: Synthetic mordenite, dissolution, mechanism, kinetics

Title:

Authors:: Kolar, Zvonko; Binsma, Johanus Jordanus Maria; Subotić, Boris (45364)

Journal: Journal of Crystal Growth
ISSN: 0022-0248
Volume: 116
Year: 1992
Pages: from 473 to 482
Number of references: 28
Language: engleski
Summary: The transformation of orthorhombic barium fluoride into cubicbarium fluoride was studied by x-ray diffraction analysis,scanning electron microscopy and particulate analysis of thesolid pahse and chemical analysis of the liquid phase during thetransformation. The transformation was found to take place bydissolution of the unstable orthorhombic modification and growthof the stable cubic modification at constant supersaturation.
Keywords: Barium fluoride, transformation, kinetics, mechanism, crystal growth

Title:

Authors:: Bronić, Josip (117985); Subotić, Boris (45364)

Journal: Journal of Radioanalitical and Nuclear Chemistry
Number: 2
ISSN: 0263-5731
Volume: 152
Year: 1991
Pages: from 339 to 350
Number of references: 24
Language: engleski
Summary: The influence of zeolite type, concentration of strontium ions insolution, temperature and flow rate on the kinetics ofion-excahnge process was studied by measuring concentration ofstrontium ions in solution before and after passing through acolumn filled with warious granulated zeolites (A, X, SM). Fromthe results obtained, the optimal conditions for the mostefficient removal of strontium ions from solutions usinggranulated zeolites can be defined.
Keywords: Strontium ions, removal, ionic excahnge, radioactive solutions, granulated zeolites

Title:

Authors:: Kosanović, Cleo (180432); Bronić, Josip (117985); Subotić, Boris (45364); Šmit, Ivan (47636); Stubičar, Mirko (45316); Tonejc, Anton (52132); Yamamoto, Tatsuya

Journal: Zeolites
Number: 4
ISSN: 0144-2449
Volume: 13
Year: 1993
Pages: from 261 to 268
Number of references: 44
Language: engleski
Summary: X-ray diffractometry, FTIR analysis, cation-exchange capacity andsolubility were used to characterize the effect of ball millingon zeolitea A, X and synthetic mordenite. Changes of IR spectraduring the ball milling show that a loss of crystallinity, adecrease of cation-excahnge capacity and an increase ofsolubility were caused by breaking of Si-O-Si and Si-O-Al bondsin the zeolite structure. Based on such a conclusion, the kineticequation of the amorphization process was derived and evaluated.
Keywords: Zeolites, amorphization, ball milling, x-ray diffraction, IR spectroscopy, cation-excahnge capacity, solubility

Title:

Authors:: Musić, Svetozar (32832); Dragčević, Đurđica (10431); Popović, Stanko

Journal: Croatica Chemica Acta
Number: 3-4
ISSN: 0011-1643
Volume: 66
Year: 1993
Pages: from 469 to 4780
Number of references: 20
Language: engleski
Summary: Four oxide phases, lepidocrocite, goethite, magnetite were found inthe corrosion products.The strong influence of (NH$)SO4 electrolyte on the phase compontion of the rust was explained by the cumulative effect of two aggresive ions, NH4+ and SO42-.Possible pathways for the formation of iron oxide phases in the rust were discused.
Keywords: STeel, corrosion, alpha-FeOOH, gamma-FeOOH, alpha-Fe2O3, Fe3O4

Title:

Authors:: Tonejc, Anton (52132); Kosanović, Cleo (180432); Stubičar, Mirko (45316); Subotić, Boris (45364); Tonejc, Anđelka; Šmit, Ivan (47636)

Journal: Journal of Material Science Letters
Volume: 13
Year: 1994
Pages: from 519 to 0
Language: engleski
Summary: It was discovered via x-ray diffraction that that the structural transformation of g-AlOOH (boehmite) and Al(OH)(gibbsite) into a-Al O (corundum) was occuring at the roomtemperature in the course of high-energy ball-mill processing ofpure powders. Thus, this new route probably offere the cheapestway of masive production of corundum powder.
Keywords: Gamma-AlOOH (bemit), Al(OH)3 (gibbsite), alpha-Al2O3 (corundum), effect of high-energy ball milling, x-ray diffraction

Title:

Authors:: Tonejc, Anton (52132); Kosanović, Cleo (180432); Tonejc, Anđelka; Stubičar, Mirko (45316); Subotić, Boris (45364); Šmit, Ivan (47636); Bronić, Josip (117985)

Journal: Journal of Alloys and Components
ISSN: 0925-8388
Volume: 204
Year: 1994
Pages: from L1 to L3
Number of references: 24
Language: engleski
Summary: It was discovered by x-ray diffraction that in the course of high-energy ball milling of pure powders of gama-Al2O3 andgama-AlOOH the structural changes occured so that the end phase in the both cases were alpha-Al2O3 (corundum). Moreover,the sequence of structural changes observed during milling wasequivalent to that which was observed in the course ofprogressive annealing of the both starting materials.
Keywords: Gamma-Al2O3 i gamma-AlOOH (boehmite), alpha-Al2O3 (corundum), transition phases, sequence of phase changes, high-energy ball milling, progressive annealing, X-ray diffraction

Title:

Authors:: Čižmek, Ankica (42414); Komunjer, Ljepša (21916); Subotić, Boris (45364); Aiello, Rosario; Crea, Fortunato; Nastro, Alfonso

Journal: Zeolites
ISSN: 0144-2449
Volume: 14
Year: 1994
Pages: from 182 to 189
Number of references: 24
Language: hrvatski
Summary: Influence of initial concentration of dissolved silica on the kinetics of dissolution of (Na, TPA)-ZSM-5 was studied by thechemical analysis of the liquid phase and phase and particulateanalysis of the dissolving solid during the dissolution. Theincrease of dissolution rate with increasing concentration ofsilicon in the liquid phase was explained in realation to different reactions which occur in the system during thedissolution.
Keywords: (Na, TPA)-ZSM-5, dissolution, kinetics, mechanism

Title:

Authors:: Musić, Svetozar (32832); Popović, Stanko; Ristić, Mira (85111)

Journal: Materials Letters
Number: 4
ISSN: 0167-577x
Volume: 23
Year: 1995
Pages: from 139 to 142
Number of references: 13
Language: engleski
Summary: Formation of solid solution in the system alpha-(AlxFe1-x)2O3, 0 Keywords: solid solution, iron(III) oxide, aluminijum(III) oxide

Title:

Authors:: Musić, Svetozar (32832); Popović, Stanko; Ristić, Mira (85111); Sepiol, B.

Journal: Journal of Material Science
Number: 7
ISSN: 0022-2461
Volume: 29
Year: 1994
Pages: from 1717 to 1718
Number of references: 16
Language: engleski
Summary: Chemical and structual properties of the system (1-x)Fe2O3+xNd2O3, 0 Keywords: Fe(III)-oxide, Nd(III)-oxide, Moessbauer, FT-IR, XRD, mathematical deconvolution

Title:

Authors:: Musić, Svetozar (32832); Gotić, Marijan (126904); Popović, Stanko; Czako-Nagy, Ilona

Journal: Materials Letters
Number: 7
ISSN: 0167-577x
Volume: 20
Year: 1994
Pages: from 143 to 148
Number of references: 16
Language: engleski
Summary: The formation of gamma-Fe2O3 by thermal decomposition of a mixture of Fe(II)- and Fe(III)-oxalate salts was investigated. It was found that the ball-milling of the starting chemicals, at the concentration ratio for the Fe3O4 formation, suppressed the formation of alpha-Fe2O3 as the phase associated with Fe2O3 during the thermal decomposition process. The correlation of the results obtained by X-ray diffraction, 57Fe Moessbauer spectroscopy and FT IR spectroscopy was shown.
Keywords: gamma-Fe2O3, magnetic material, Moessbauer, XRD, FT-IR

Title:

Authors:: Gotić, Marijan (126904); Popović, Stanko; Musić, Svetozar (32832)

Journal: Materials Letters
Number: 11
ISSN: 0167-577x
Volume: 21
Year: 1994
Pages: from 289-2 to 295
Number of references: 23
Language: engleski
Summary: Formation of delta-FeOOH was investigated by varyng the experimental conditions of its synthesis. Strong alkalina mother liquor was an important factor for delta-FeOOO formation via the Fe(OH)2 precursor. A small amount of Fe3+ ions in the Fe(OH)2 precursor before the rapid oxidation of Fe2+ ions with H2O2 solution, was not critical for the formation of FeOOH as a singe phase. The best crystallinity of delta-FeOOH was obtained when the syntesis was performed in an inert atmosphere. Transmision electron microscopy showed that delta-Feooh particles were present in the form of thin plates. FTIR spectra of the samples prepared are discussed.
Keywords: delta-FeOOH, crystallinity, XRD, FT-IR

Title:

Authors:: Musić, Svetozar (32832); Dragčević, Đurđica (10431); Popović, Stanko

Journal: Materials Letters
Number: 6
ISSN: 0167-577x
Volume: 24
Year: 1995
Pages: from 59 to 64
Number of references: 19
Language: engleski
Summary: Colloidal particles of boehmite, formed by precipitation from AlCl3 solutions, have been investigated using X-ray diffraction, Fourier transform infrared spectroscopy and transmision electron microscopy. Strongeffects of the pH of precipitatuin of aluminium hydroxide and the mode of its drying on the phase composition of the precipitate were observed. The experimental conditions for the preparation of boehmite films, without use of Al-organic precursor or organic peptiying aents, were determined. It was found that the crystallite siye in the boehmite films was of the order of 2 or 3 nm.
Keywords: Boehmite, gibbsite, bauerite, particle size

Title:

Authors:: Musić, Svetozar (32832); Popović, Stanko; Czako-Nagy, Ilona; Dalipi, S.

Journal: Croatica Chemica Acta
Number: 3
ISSN: 0011-1643
Volume: 67
Year: 1994
Pages: from 337 to 346
Number of references: 16
Language: engleski
Summary: Oxide phases generated during the syntesis of NiFe2O4 from aqueous Ni(NO3)2/Fe(NO3)3 solution were characterized by X-ray diffraction, Fourier transform IR spectroscopy, and 57Fe Moessbauer spectroscopy. Nitrate salts and alpha-Fe2O3 were observed in the samples prepared at temperatures up to 300-degrees-C. The formation of nickel ferrite was observed at temperatures of 500-degrees-C and higher. Stoichiomertic NiFe2O4 was obtained at 1350-degrees-C. NiO and alpha-Fe2O3 were intermediate phases in the process of nickal ferrite formation. Decomposition of nitrate groups was followed by Fourier transform IR spectroscopy.
Keywords: Nickel ferrite, Moessbauer, FT-IR, XRD

Title:

Authors:: Ristić, Mira (85111); Popović, Stanko; Czako-Nagy, Ilona; Musić, Svetozar (32832)

Journal: Croatica Chemica Acta
Number: 3
ISSN: 0011-1643
Volume: 67
Year: 1994
Pages: from 337 to 346
Number of references: 26
Language: engleski
Summary: Formation of oxide phases in the system Fe2O3-Sm2O3 was investigated. The samples were prepared by the solid state reactions at two molar ration of Fe2O3 and Sm2O3. The following oxide phases were detected by X-ray diffraction: C-Sm2O3, B-Sm2O3, alpha-Fe2O3, SmFeO3 and Sm3Fe5O12. For the molar ratio Fe2O3:Sm2O3 = 1:1, SmFeO3 was detected as one of the oxide phases at temperatures up to 800-degrees-C and as a single phase at 1000-degrees-C and higher temperatures. For the molar ratio Fe2O3:Sm2O3 = 5:3, Sm3Fe5O12 was found as a single phase at 1300-degrees-C.
Keywords: hematite, garnet, perovskite, phase composition

Title:

Authors:: Musić, Svetozar (32832); Dragčević, Đurđica (10431); Popović, Stanko; Czako-Nagy, Ilona

Journal: Croatica Chemica Acta
Number: 2
ISSN: 0011-1643
Volume: 68
Year: 1995
Pages: from 315 to 323
Number of references: 15
Language: engleski
Summary: Chemical and structual properties of rust formed by corrosion of steel in water and (NH4)2SO4 solution at 20-degrees-C for time periods up to 6 months were investigated. Three oxide phases, gamma-FeOOH (lepidocrocite), Fe3O4 (magnetite) and alpha-FeOOH (geothite) were detected in the rust samples. The distribution of these phases in the rust was depended on the time of corrosion and contretation of (NH4)2SO4. Magnetit was not observed in the rust generated in 2M (NH4)2SO4 solution. The strong influence of (NH4)2SO4 electrolyte on the corrosion of steel in aqueous medium was explained as a cumulative effect of two aggresive ions, NH4+ and SO4 2-.
Keywords: Water medium, steel, corrosion, rust, (NH4)2SO4

Title:

Authors:: Musić, Svetozar (32832); Gotić, Marijan (126904); Popović, Stanko; Furić, Krešo; Mohaček, Vlasta

Journal: Journal of Material Science
ISSN: 0022-2462
Volume: 29
Year: 1994
Pages: from 1227 to 1232
Number of references: 26
Language: engleski
Summary: Structual properties of lead vanadate glasses containing La3+ or Fe3+ ions were investigated. Crystalline Pb2V5O7 was formed for the molar composition 66.7PbO-33.3V2O5. Incorporation of greater quantities of La3+ into lead metavanadate glass caused the crystallization of Pb2V2O7. Fourier transform infrared and Raman spectra also suggested the presence of LaVO4. Incorporation of Fe3+ ions into lead metavanadate glass, up to 20 wt% Fe2O3, did not cause crystallization inside the glass matrix.
Keywords: lead, vanadates, glass, lanthanum(III), iron(III)

Title:

Authors:: Musić, Svetozar (32832); Orehovec, Zvonko; Popović, Stanko; Czako-Nagy, Ilona

Journal: Journal of Material Science
ISSN: 0022-2461
Volume: 29
Year: 1994
Pages: from 1991 to 1998
Number of references: 32
Language: engleski
Summary: The structural properties of the solid phase, formed by the hydrolysis of Fe3+ ions in Fe2(SO4)4 solutions at 90 or 120-degrees-C, were investigated. The concentation regions of Fe2(SO4)3 were determined for the precipitation of goethite, alpha-FeOOH, orhydronium jarosite, H3OFe3(OH)6(SO4)2, as a single phase. Superparamagnetic behaviour of alpha-FeOOH particles was observed. Hyzdrolysis of Fe3+ ions in 0.1 M Fe2(SO4)3 solutions at 120-dergees-C produced H3OFe3(OH)6(SO4) and basic sulphate, Fe4(OH)10SO4. The interpretation of 57Fe Moessbauer and FT-IR spectra is given.
Keywords: Iron(III) hydrolysis, basic sulphates, jarosite, goethite

Title:

Authors:: Musić, Svetozar (32832); Dragčević, Đurđica (10431); Popović, Stanko; Turković, Aleksandra

Journal: Materials Letters
Number: 2
ISSN: 0167-577x
Volume: 18
Year: 1994
Pages: from 309 to 312
Number of references: 14
Language: engleski
Summary: Experimental conditions for the preparation of transparent gamma-AlOOH (boehmite) films were investigated. TEM releaved a fibrous morphology of gamma-AlOOH particles. Transparencz of the films for visible light was preserved up to 900-degrees-C, while after heating up to 1050-degrees-C the film became white. X-ray powder diffraction showed the transition from gamma-AlOOH (90-degrees-C) to gamma Al2O3 (500 to 900-degrees-C) and finaly to alpha-Al2O3 and tetha-Al2O3(1050-degrees-C). Electrical conductivity of the films was measured.
Keywords: gamma-AlOOH, transparent film, elecrical conductivity

Title:

Authors:: Langlet, M; Hochu, F.; Musić, Svetozar (32832)

Journal: Solid State Comunications
Number: 3
ISSN: 0038-1098
Volume: 94
Year: 1995
Pages: from 211 to 215
Number of references: 20
Language: engleski
Summary: Diffuse reflactance spectra of octahedral iron(III) in YnFexGa2-xO4 and alpha-FexGa2-xO3 systems in the range 4000-50000 cm-1 are presented. Bands assignments and optical parameters are in agreement with the results of SCF-Xalpha-SW molecular orbital calculations of (FeO69-) coordination. The 135-dergees-C Fe3+-O-Cr3+ antiferromagnetic interactions in the corundum structure and the 125-degrees-C Fe3+tetra-O-Cr3+octa interactions in the spinel structure induca the growth of a large electronic transition at 1.70 eV assigned to an intervalence chenge transfer.
Keywords: optical spectra, corundum structure, spinel strukture, molecular orbitals

Title:

Authors:: Gotić, Marijan (126904); Popović, Stanko; Ljubešić, N.; Musić, Svetozar (32832)

Journal: Journal of Material Science
ISSN: 0022-2461
Volume: 29
Year: 1994
Pages: from 2474 to 2480
Number of references: 21
Language: engleski
Summary: The structural properties of precipitates formed by hydrolysis of Fe3+ ions in aqueous solutions, containing NO3- and Cl- ions, were investigated. X-ray diffraction showed thet alpha-FeOOH and alpha-Fe2O3 were present in hydrolytical products formed in solution containing NO3- ions, while betha-FeOOH and alpha-Fe2O3 were typical products in solution containing Cl-ions. In the mixed Fe(NO3)3 + FeCl3 solutions, the phase composition of the hzdrolytical products was determined by the concentration of dominant Fe(III) - salt

Title:

Authors:: Kamnev, Alexander A.; Ristić, Mira (85111); Angelov, Venelin

Journal: Journal of Molekular Structure
Number: 4
ISSN: 0400-020
Volume: 349
Year: 1995
Pages: from 77 to 80
Number of references: 13
Language: engleski
Summary: Transmission Moessbauer and Fourier transform infrared spectroscopic data obtained for binary nickel(II)-iron(III) hydroxide systems in a broad range of compositions (3 to 60 at % Fe/(Ni+Fe) are compared. The formation of a nickel ferrite precursor is shown to be promoted in the crystallites surfaces layers even at mutch lower gross Fe-to-Ni ratios than in NiFe2O4 owing to surface enrichement with iron, as confirmed by Auger electron spectroscopic analyses
Keywords: Oxygen evolution reaction, nickel(II) hydroxide

Title:

Authors:: Tonejc, Anton (52132); Stubičar, Mirko (45316); Tonejc, Anđelka; Kosanović, Cleo (180432); Subotić, Boris (45364); Šmit, Ivan (47636)

Journal: Journal of Material Science Letters
ISSN: 0261-8028
Volume: 13
Year: 1994
Pages: from 519 to 520
Number of references: 10
Language: engleski
Summary: Phase transition in boehmite and giggsite during their high-energy ball-milling were followed by X -ray diffractometry. The results of analyses showed that boht boehmite and gibbsite can be transformed to corundum during the milling. The obtained results indicate the equivalence of milling and heat treatment for transition of boehmite and gibbsite to corundum.
Keywords: Transformation, hight-energy ball-milling boehmite, gibbsite, corundum

Title:

Authors:: Kosanović, Cleo (180432); Čižmek, Ankica (42414); Subotić, Boris (45364); Šmit, Ivan (47636); Stubičar, Mirko (45316); Tonejc, Anton (52132)

Journal: Zeolites
ISSN: 0144-2449
Volume: 15
Year: 1995
Pages: from 632 to 636
Number of references: 19
Language: engleski
Summary: The influence of the partial exchange of sodium ions from zeolite A by other cations (Li+, Na+,K+,Cs+ and NH4+) on the kinetics of amorphisation was investigated by X-ray diffractometry and FTIR spectroscopy. Analysis of the experimental results has shown that the partial exchange does not affect the basic mechanism of the amorphization process, but only the rate of amorphization. The rate of amorphization is related to the volume occuped in a unit cell of zeolite A by the cations.
Keywords: Zeolite A, cation exchange, rate of amorphisation, ball milling, X-ray difractometry, FTIT-analysis

Title:

Authors:: Kosanović, Cleo (180432); Čižmek, Ankica (42414); Subotić, Boris (45364); Šmit, Ivan (47636); Stubičar, Mirko (45316); Tonejc, Anton (52132)

Journal: Zeolites
Number: 1
ISSN: 0144-2449
Volume: 15
Year: 1995
Pages: from 51 to 57
Number of references: 28
Language: engleski
Summary: The samples obtained during ball milling of zeolite ZSM-5 were characterized by different methods such as X-ray diffractomertry, scanning-electron microscopy, FTIR spectroscopy, and simultaneous thermal analysis. Very slow rate of amorphization of "as-synthesized" zeolite as compared with the rate of amorphization of its "activated" form is explained by the stabilizing effect of TPA+ ions present on the strukture of the as-synthesized zeolite.
Keywords: Mechanochemistrz, amorphisation, zeolite ZSM-5

Title:

Authors:: Kosanović, Cleo (180432); Bronić, Josip (117985); Čižmek, Ankica (42414); Subotić, Boris (45364); Šmit, Ivan (47636); Stubičar, Mirko (45316); Tonejc, Anton (52132)

Journal: Zeolites
Number: 3
ISSN: 0144-2449
Volume: 15
Year: 1995
Pages: from 247 to 252
Number of references: 9
Language: engleski
Summary: Change in partculate and morphological properties of the samples obtained during the high-energy ball-milling of zeolite A and X were studied by scanning-electron microscopy, X-ray diffraction and determination of particle size distribution. It was found that decrease of crystallinity is followed by considerable change of particulate properties during the milling, but that the change of particulate properties and amorphization are two independent processes.
Keywords: Zeolites, amorphization, ball milling particulate processes

Title:

Authors:: Dutta, Prabir K.; Bronić, Josip (117985)

Journal: Zeolites
ISSN: 0141-2449
Volume: 14
Year: 1994
Pages: from 250 to 255
Number of references: 22
Language: engleski
Summary: The mutual interactions between zeolite Y seed crystals and amorphous aluminosilicate gels has been examined in a reactor system in witch seed crystals and gel are separated by a 0.2 um membrane. The results indicate that the seed crystals modify the crystallization process if they are in physical contact with the gel, but do no influence it if they are kept separated via the membrane, suggesting that solution species, but not nuclei travel freely accros the membrane.
Keywords: Zeolite nucleation, membrane reactor system, tanjasite zeolite Y, zeolite P

Title:

Authors:: Antonić, Tatjana; Čižmek, Ankica (42414); Subotić, Boris (45364)

Journal: Journal of Chemical Society Faraday Transactions
Number: 13
ISSN: 0956-5000
Volume: 90
Year: 1994
Pages: from 1973 to 1977
Number of references: 22
Language: engleski
Summary: The influence of the initial mass of the solid phase and concentration of NaOH on the kinetics of dissolution of an amorphous alumosilicate precursor hes been studies by measuring the aluminium and silicon concentration in the liquid phase during dissolution at 80-degree-C. The proces of dissolution is controlled by two reactions: a forward one, whose rate is proportional to the outher surface area, S, of the solid phase a backward one, whose rate is proportional to the concentration of reactive silicate and aliminate species from the liquid phase.
Keywords: Dissolution,amorphous zeolite precursor, alkaline solution, mechanism of dissolution

Title:

Authors:: Antonić, Tatjana; Čižmek, Ankica (42414); Subotić, Boris (45364)

Journal: Journal of Chemical Society Faraday Transactions
ISSN: 0956-5000
Volume: 90
Year: 1994
Pages: from 3725 to 3728
Number of references: 14
Language: engleski
Summary: The influence of temperature on the kinetics of dissolution of the amorphooooooooooooooous aliminosilicate precursor has been studied by measuring the change in the Al and Si concentrations in the liquid phase during the dissolution in 0.2 mol l-1 NaOH solution. The change in the dissolution temperature does not affect the mechanism of the dissolution, only the rate of the foward and beck reactions.
Keywords: Dissolution, amorphous zeolite precursor, alkaline solutions temperature

Title:

Authors:: Bronić, Josip (117985); Subotić, Boris (45364)

Journal: Microporous Material
Number: 2-3
ISSN: 0927-6513
Volume: 4
Year: 1995
Pages: from 239 to 242
Number of references: 30
Language: engleski
Summary: Different mechanism of nucleation in the liquid phase were assumed in the literature as the dominant processes of the formation of primary zeolite particles. Analysis of three different crystalizing systems show that the rate of homogeneous nucleation is extremly low under the given synthesis conditions, so the other nucleations processes must be considered relevant for the formation of primary zeolite particles.
Keywords: Zeolites, homogeneous nuleation, heterogeneous nucleation, rate of nucleation, crystallization

Title:

Authors:: Čižmek, Ankica (42414); Subotić, Boris (45364); Aiello, Rosario; Crea, Fortunato; Nastro, Alfonso; Tuoto, Claudia

Journal: Microporous Material
Number: 2-3
ISSN: 0927-6513
Volume: 4
Year: 1995
Pages: from 159 to 168
Language: engleski
Summary: Dissolution of high-silica pentasils (silicalite-1, ZSM-5) with different Al content in 5 M NaOH solution at 60-degree-C was investigated with differnt methods. Analysis of the experimental results showed that the initial rate of dissolution is directly proportional to tha surface area of the dissolving solids and that the rate constant is linear function of the silica-to-alumina ratio of the dissolving solids.
Keywords: ZeoliteZSM-5, silicalite-1, aluminium content, dissolution, kinetics


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