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Public memorialisation in Bosnia and Herzegovina today is an act of remembering not just those who died in the conflict but also the multi-ethnic reality of earlier times. Articulation of this, however, is being obstructed in cities like Prijedor.

The objective of this paper was to evaluate the 5-year incidence of obesity on a sample of 3229 adults and investigate the potential effect of several sociodemographic and lifestyle habits on weight change and obesity incidence in these individuals. The average annual rate of increase in the prevalence of obese adults between 2003 and 2008 was 10.60% for men and 11.08% for women. Analysis showed that development of obesity in 5-year period in women in Croatia is significantly positively associated with frequent consumption of "hidden" fats of animal origin and significantly negative with each higher education level. No significant predictor of obesity has been found in men. Obesity remains a serious health problem for the Croatian population; the alarming rates of excess body weight continue to increase. Preventive measures should urgently be undertaken.

The effect of small amounts of ruthenium on the formation of magnetite in highly alkaline media was investigated using X-ray powder diffraction (XRD), Mossbauer and FT-IR spectroscopies, field emission scanning electron microscopy (FE-SEM) and energy dispersive X-ray spectroscopy (EDS). Acicular alpha-FeOOH particles precipitated in a highly alkaline medium with the addition of tetramethylammonium hydroxide (TMAH) were used as a reference material. Initial addition of small amounts of Ru(NO)(NO3)(3) to that precipitation system had a drastic effect on the formation of iron oxide phases and their properties. The addition of Ru(NO)(NO3)3 favoured the formation of stoichiometric Fe3O4. With an increase of the initial Ru(NO)(NO3)3 concentration in the precipitation systems less time was needed for the formation of Fe3O4 as a single Fe-bearing phase in the precipitates. Ruthenium ions made solid solutions alpha-(Fe,Ru)OOH; however, there was no indication of the formation of solid solutions with alpha-Fe2O3 and Fe3O4, Mossbauer and FT-IR spectroscopies supported the conclusion on the formation of solid solutions a-(Fe,Ru)OOH. FE-SEM showed the formation of octahedral Fe3O4 Particles of a mu m range size. Ruthenium particles (approximate to 20 nm in size) were deposited onto the surfaces of Fe3O4 particles. They were also present in the form of clusters containing octahedral Fe3O4 particles in the nanosize range (approximate to 100 nm or less). The formation of Fe3O4 was interpreted as a combining effect of the thermal decomposition products of TMAH under autoclaving conditions and the catalytic action of ruthenium. In such a way strong reductive conditions in the investigated precipitation system were created.

The effect of bicarbonate/carbonate ions on the formation of iron rust in an aqueous medium has been investigated using XRD, Mossbauer and FT-IR spectroscopies. Corrosion of carbon steel in doubly distilled water was monitored as a reference process. Lepidocrocite as the dominant phase and magnetite were detected in rust generated in doubly distilled water in a period from three weeks to one year at room temperature. At 90 degreesC, magnetite and small amounts of hematite/goethite were formed in a period from one day to three weeks. In these rust samples, FT-IR spectroscopy detected a very small amount of lepidocrocite, which dissolves and thus occurs in overall phase transformations in rust. On the other hand, goethite was found as the dominant phase in rust formed in natural water containing a significant amount of bicarbonate ions, whereas magnetite and lepidocrocite were minor phases. In 0.005 M Na2CO3, goethite and magnetite were generated at room temperature, and after one month of corrosion, magnetite was present only in traces. Corrosion in 0.005 M Na2CO3 at 90 degreesC generated Fe-2(OH)(2)CO3 and magnetite. A certain analogy between the precipitation of Fe-III-oxyhydroxides from iron-salt solutions containing carbonates and the formation of goethite and lepidocrocite in rust was shown. Mossbauer spectroscopy showed that microstructural properties of the oxide phases also varied. Magnetite showed substoichiometry (Fe3-xO4) and in some cases it was difficult to distinguish between Fe3-xO4 and maghemite (gamma-Fe2O3). Mossbauer spectra, recorded as a function of temperature, showed poor crystallinity and/or superparamagnetic behavior of goethite particles. Also, the Mossbauer spectra of the rust formed in carbonate solutions provided evidence of the amorphous fraction, which is in agreement with XRD. The difference between the results of the present investigation and those obtained by other researchers can be attributed to the electrochemical stimulation of steel (iron) surfaces in bicarbonate/carbonate aqueous media and the shorter corrosion times used in their experiments.

U zadnje dvije dekade postoji snažan interes znanstvene zajednice kao i visoko-tehnološke industrije za materijalima koji u svojem nazivu imaju prefiks "nano", npr. nanoˇcesticama, nanokristalima, nanostrukturama. Nano ˇcestiˇcni materijali pokazuju veliko bogatstvo novih temeljnih fiziˇckih fenomena koji se gotovo u potpunosti razlikuju od onih u makroskopskim sistemima. Ciljana nanostrukturna istraživanja u Laboratoriju za molekulsku fiziku IRB-a poˇcinju vec poˇcetkom devedesetih godina istraživanjem nanostrukturnih defekata u amorfnom siliciju i galijevom arsenidu u suradnji s grupom T. E. Haynesa, SAD. Sredinom devedesetih istraživanja se proširuju na oksidne nanoˇcestice dobivene sol-gel metodom u suradnji s grupom Dr. S. Musi´ca i na nanoˇcestice CdxSe1-x u staklenoj matrici u suradnji s grupom Prof. W. Kiefera, Njemaˇcka. Trenutna istraživanja se još odvijaju u suradnji s talijanskim znanstvenicima na TiO2 nanoˇcesticama u kvarcnoj matrici dobivenih sol-gel metodom u suradnji s grupom prof. M. Montagne, Si - nanoˇcesticama u kvarcnoj matrici u suradnji s prof. L. Pavesijem i helijem induciranim nanostrukturama u siliciju u suradnji s prof. G. Mariottom. U okviru ovog rada biti ´ce prikazane osnove teorije Ramanovog raspršenja na nanoˇcesticama kao i zanimljiviji primjeri primjene Ramanove spektroskopije na nanostrukturama.

Titania, TiO2, is a technologically interesting material because of its catalytic and electronic properties. Its properties, however, change when it is doped with metal atoms or when prepared to have a very small crystallite size [R. J. H. Clarc, The Chemistry of Titanium and Vanadium, Elsevier Publ. Co., New York, 1968]. In this work we examined the influence of iron doping on structural properties of titania. Polycrystalline titania and Fe-doped titania samples containing 0.5, 1.1, 2.6, 8.1 and 18 at% Fe were prepared by a sol-gel technique. Ti(IV)-isopropoxide and Fe(III)-nitrate were used as precursors of titanium and iron. Synthesis was performed in a nitrogen inert atmosphere under alkaline conditions, which was accomplished by addition of NH3. As-synthesized samples were annealed at 500 °C for 2 hours. The samples were examined by X-ray powder diffraction at room temperature. Sample of pure titania was anatase (tetragonal, S. G. I41/amd). Sample with 0.5 at% Fe was an anatase-type solid solution. For Fe doping level higher than 0.5 at% Fe the samples contained two phases, that of anatase-type and of rutile-type (tetragonal, S. G. P42/mnm), respectively. Anatase phase was dominant for all the doped samples. The sample with 18 at% Fe contained impurity, namely ~5% Fe2TiO5. All the samples were nanocrystalline, with crystallite sizes in the range 10-20 nm. Diffraction line broadening increased with Fe doping level. Unit-cell parameters were determined using Si as an internal standard, and refined by the whole powder pattern fitting [WPPF program, H. Toraya, J. Appl. Cryst. 19 (1986) 440]. Iron doping increased slightly unit-cell parameters of both anatase- and rutile-type phases. The Rietveld method [H. M. Rietveld, J. Appl. Cryst. 2 (1969) 65] was performed to refine the crystal structure of obtained phases, and the real incorporation level of Fe into the anatase and rutile lattices was determined.

The effects of urotropin on the hydrolysis of Fe3+ ions in NH4Fe(SO4)2 solutions at 90°C were investigated using X-ray powder diffraction, 57Fe Mössbauer spectroscopy and Fourier transform infrared spectroscopy and transmission electron microscopy. Three concentrations of NH4Fe(SO4)2 solutions, 0.03, 0.1 and 0.5 M, with varying initial amounts of urotropin were used in the experiments. Chemical and structural properties of the precipitates strongly depended on the concentrations of the reactants and the time of hydrolysis. In the early stages of Fe3+ hydrolysis, samples were dominantly amorphous. α -FeOOH, α -Fe2O3 and NH4Fe3(OH)6(SO4)2 were crystalline phases detected in the precipitates; however, the specific phase composition of each precipitate depended on the experimental conditions. The possible formation of schwertmannite was not proved in the precipitates. It was suggested that the particles of amorphous fraction, as well as α-FeOOH particles, contained significant amounts of sulphates on external and internal surfaces due to the specific adsorption. Regularity in the phase composition of the precipitates, as a function of the experimental conditions, was found. Crystallite sizes of oxides were estimated on the basis of the broadening of diffraction lines. Mössbauer spectroscopy indicated superparamagnetic behavior of a-FeOOH particles. Formation of a-FeOOH particles of colloidal dimensions was proved by transmission electron microscopy. Utjecaj urotropina na hidrolizu iona Fe3+ u vodenim otopinama NH4Fe(SO4)2 pri 90 °C istraživan je primjenom rentgenske difrakcije u prahu, Mössbauerove spektroskopije i FT-IR spektroskopije. U eksperimentima su korištene otopine NH4Fe(SO4)2 (0.03, 0.1 i 0.5 mol dm–3) koje su sadržavale i različite količine urotropina. Kemijska i strukturna svojstva taloga jako su ovisila o koncentracijama reaktanata i trajanju hidrolize. U početku hidrolize iona Fe3+ uzorci su bili pretežno amorfni. U talozima su na|ene najviše tri kristalne faze: α-FeOOH, α-Fe2O3 i NH4Fe3(OH)6(SO4)2, a fazni sastav taloga ovisio je o eksperimentalnim uvjetima. Faznom analizom taloga nije dokazano nastajanje švertmanita. Čestice amorfne frakcije taloga, ali i čestice α FeOOH, sadržavale su znatne količine sulfata što je objašnjeno specifičnom adsorpcijom tog aniona. Nađena je zakonitost ovisnosti faznog sastava taloga o eksperimentalnim uvjetima. Veličine malih kristala nastalih oksidnih faza dobivene su na temelju proširenja difrakcijskih linija i primjenom Scherrerove jednadžbe. Superparamagnetsko ponašanje čestica -FeOOH utvrđeno je Mössbauerovom spektroskopijom.

The chemical and microstructural properties of oxide phases obtained by forced hydrolysis of Fe ions at 90°C, were investigated using X-ray powder diffraction, Fourier transform infrared spectroscopy, 57Fe Mössbauer spectroscopy and transmission electron microscopy. Urotropin (hexamethylenetetramine) was used as a generator of OH ions. After 5 hours of the hydrolysis of 0.1 M Fe(NO3)3 solution in an acidic medium the RT Mössbauer spectrum showed a broad size distribution of a-FeOOH particles, while XRD showed the presence of an amorphous fraction and a-FeOOH. With a prolonged heating time a-FeOOH was transformed to a-Fe2O3 by a dissolution/reprecipitation mechanism. At the beginning of precipitation process the amorphous fraction increased with an increase of urotropin concentration and for 0.25 M urotropin the sample was completely amorphous, as shown by XRD. For the same sample RT Mössbauer spectrum showed a quadrupole doublet. After 3 and 5 hours of aging of the precipitation system in the presence of 0.1 M urotropin, traces of a-FeOOH were observed in the FT-IR spectra, while for 0.25 M urotropin FT- IR spectroscopy did not show any a-FeOOH content. For longer ageing times (7 and 21 days) of the precipitation systems mixtures of a-Fe2O3 and a- FeOOH were found and tendency of the a-FeOOH fraction to increase with an increase in the urotropin concentration was observed. A possible mechanism of crystallization of a-Fe2O3 and a- FeOOH from an amorphous phase in the near neutral pH region is discussed. The size and morphology of oxide particles depended strongly on the experimental conditions of their formation.

Precipitations of iron oxides from FeCl3 solutions in the presence of urotropin at 90 degrees C were monitored using the Fourier transform infrared spectroscopy, Mossbauer spectroscopy, X-ray diffraction and transmission electron microscopy. Urotropin was used as a generator of OH- ions. The precipitation processes depended on the concentrations of FeCl3 and urotropin and the time of aging. After 1 day of aging the precipitation systems up to pH approximate to 2, the beta-FeOOH phase was precipitated, while in the region of 5 < pH < 6 the mixtures of beta-FeOOH, alpha-Fe2O3 and alpha-FeOOH were precipitated, and at pH > 6 the mixtures of alpha-Fe2O3 and alpha-FeOOH were observed. The beta-FeOOH phase precipitated at 2.16 < pH < 5.55 dissolved after 7 days, yielding soluble iron for the alpha-FeOOH growth on account of alpha-Fe2O3. At pH approximate to 1.5 and less, beta-FeOOH was present as a single phase up to 7 days of aging the precipitation systems. The mechanisms of iron oxide precipitation in dependence on pH were discussed. The size and morphology of oxide particles were strongly influenced by experimental conditions of the precipitation process as shown by transmission electron microscopy.

Two different ingots of leucite-type glass-ceramics were studied by integral and by partial thermally stimulated depolarization current (TSDC) in the range from 173 to 370 K. Partial measurements showed distributed dipolar relaxation (P-1) with a maximum at 256 K, caused by the interaction between alkali ions and nonbridging oxygen atoms. The following relaxation, observed at a higher temperature (P-2), was attributed to the decay of the space charge dipoles. Only the beginning of P-2 was studied because the development of the process was overlapped by the conductivity current. Addition of different oxides to the original material decreased the P-1 and increased the P-2 relaxation, due to the increase of the interface area.

Bacterial biofilms are involved in many human bacterial infectious processes and in chronic rhinosinusitis as well. The aim of this study was to determine whether biofilm exists in nasal polyps, both in diffuse nasal polyposis (DNP) and antrochoanal polyps (ACP). Method: Tissue samples were taken front seven patients suffering from DNP and three patients suffering from ACP, based on the defined patient inclusion and exclusion criteria. After the preparation, the tissue samples were analyzed by means of scanning electron microscopy (SEM) for signs of biofilm formation. Results: Signs of biofilm presence were found in all DNP patients. In ACP cases, biofilm was found in the stalk and nasal, polypoid part of the ACP, whereas there were no signs of biofilm on diseased mucosa of the posterior wall of the maxillary sinus. Conclusions: Our preliminary study showed a possible role of bacterial biofilm in pathogenesis and maintenance of both DNP and ACP. There are no obvious differences in the SEM appearance of biofilms in DNP and ACP Future research is needed to explain why biofilm is present in cases of diffuse nasal polyposis and at the nasal part of ACP, but not on the maxillary sinus part of ACP.

Microstructure of leucite-type dental glass-ceramics was investigated using X-ray diffraction, Fourier transform infrared spectroscopy, laser Raman spectroscopy, scanning electron microscopy and energy dispersive X-ray spectrometry. The main features of the FT-IR and laser Raman spectra were similar to those of silicate glasses containing Al3+ or other M3+ (M = metal) as network forming ions. Two weak IR bands at 640 and 543 cm(-1) were typical of all leucite glass-ceramics. These IR bands disappeared with the conversion of leucite glass-ceramics to the glass state. The laser Raman spectrum of leucite-type glass exhibited one unusual band centred approximately at 4600 cm(-1) possessing the fluorescence/luminescence spectral feature together with two luminescence sharp peaks at 5037 and 5007 cm(-1). The effects of quenching (cooling) on the morphological and chemical properties of leucite-type dental glass-ceramics were monitored. [References: 20]

Commercially available silicon-on-insulator (SOI) wafers, consisting of 45  m tick p-type (111) epitaxial layer grown on a thin 100 nm SiO2 layer on n-type silicon substrate were electrochemical etched to produce porous silicon (PSi) samples. At 50% concentration of 48% hydrofluoric acid (HF) in ethanol solution the micro- and nano-sized pores were obtained. The structural and the optical properties of prepared sample were investigated by Raman spectroscopy, Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). SEM images showed high density of micrometer sized pores. Nanometer sized structures were observed by the phonon confinement effects of the optical and acoustic phonon bands in the Raman spectra. The broadening of crystal silicon (c-Si) transversal optical TO( ) band at 520 cm-1, was observed in substrate sample. At the same time the wide transversal acoustical (TA)-like phonon band at 150 cm-1, that characterizes the short range confinement, also appeared in the same sample. FT-IR spectra exhibited numerous bands from Si-Hx and H-Si(Si3-nOn) groups. The sample also showed photoluminescence (PL) peak in the visible spectral range. The change in the intensity, width and the position of the PL peak showed strong sensitivity to the influence of different environment conditions such as air, vacuum and acetone.

The silicon rich oxide (SiOx) thin films were prepared in the LPCVD reactor, by thermal oxidation of silane in oxygen atmosphere and in nitrous oxide atmosphere. The stechiometry coefficient x was controlled by the substrate temperature and the ratio of the partial pressures of silane and oxidants O2 and N2O. The structural and optical properties of prepared SiOx films were analyzed by infrared spectroscopy, Raman spectroscopy and scanning electron microscopy.

Siloxane structures developed under low pressure were examined with raman spectroscopy and monitored under mid-magnification microscope. The accelerated decrease of water contents hinders the formation of siloxane ladder structures.

The synthesis of alpha-aminophosphonate derivatives has attracted current interest in the organic and medicinal chemistry due to important biological and pharmacological properties of these organophosphorus compounds.[1] Another interesting aspect regarding this kind of compounds arises from their ability of forming various types of transition metal complexes, which might also be of interest owing to their biological activity.[2] The classical Kabachnik-Fields reaction, a three-component one-pot reaction of amine, carbonyl compound (aldehyde or ketone) and hydrophosphoryl compound, has proven its great synthetic potential and significance as one of the simplest approaches to alpha-aminophosphonates.[3] We have directed out attention to investigations on the course of microwave-assisted one-pot three-component reaction of quinoline-3-carboxaldehyde and aniline (Scheme 1) as well as 3-aminoquinoline and benzaldehyde (Scheme 2), respectively, with diethyl phosphite. Here, we present 1H and 31P NMR, MS and IR spectroscopic characterization of unusual monoester phosphonate derivatives (2, 3, 5) isolated along with diethyl phosphonates (1, 4).

The structure and vibrational spectra of hybrid polymers based on 3-glicidoxypropyltrimethoxysilane was investiganted by vibrational spectroscopy and DFT calculations.