Preliminary investigations of deterioration on monument to fallen soldiers in the second world wаr in Stip, Republic of Macedonia

This paper gives an explanation of the origin and formation on the minerals which are formed as a consequence on deterioration. Several small marble samples were collected for research by Scanning electron microscopy (SEM), coupled with an energy dispersive X-ray spectrometer (EDS). SEM is especially useful because it gives elemental, mineralogical and morphological data at the same time. Loss of face characters and presence of black crusts are evident. The results show that the black crusts consisting of gypsum, calcite and elements such as Si, Al, Fe, Pb, Ti, Zn and Mn, were being formed from interaction between the marble surface and atmospheric pollutants. Dissolution of calcite from the surface by rain water, CO2 and SO2 enables the Fe compounds to become enriched and oxidized on the surface. Clay minerals are occur in the finishing layers covering the surface on the monument and they originated from atmospheric dust naturally deposited. Key words: мarble; deterioration; black crust; soil dust; environmental condition

Orthorhombic Crystal Structure of Grossular Garnet (Suva Česma, Western Serbia): Evidence from the Rietveld Refinement

The grossular garnet from rodingite-type rock from the Suva Česma area in western Serbia is characterized with its weak anisotropic nature. Because its anisotropy could indicate a non-cubic lower symmetry, SEM-EDS and Rietveld powder refinement methods were used. The SEM-EDS results have shown that the garnet has a (Ca3.00Mn0.01)3.01(Al1.82Fe0.15Ti0.02)1.99(Si2.97Al0.03)3.00O12 chemical composition (i.e., Grs91Adr08), which can be more specifically explained as ferric iron containing grossular. The next step further used Rietveld powder refinements of the various crystal structures in the Ia‾3d, R‾3c, R‾3, I41/a, Fddd, C2/c, and I‾1 space groups as well as a single mixture, which was followed by a comparative analysis of the R-values, site occupancy factors, and bond lengths and angles. The synthesis of these results showed both that the studied grossular garnet is not cubic and that it crystallized in the disordered Fddd space group with the final RB = 5.29% and RF = 1.75%. It was presumed that the grossular formed at temperatures between 150 and ~600 °C

Mineralogical and petrological characteristic of igneous rocks used for making polished stone tools from the Eneolithic archaeological site Masinske Njive (Serbia)

In this study we report results of mineralogical and petrological investigations of 12 samples, which represent raw material used for making polished stone tools from the Eneolithic archaeological site Masinske Njive (Serbia). It is located about 45 km southwest from Belgrade, within the largest Serbian coal mining field called “Kolubara”, in the close vicinity to the Starčevo and Eneolithic archaeological site Jaričište. The applied methods – optical transmitted light microscopy and SEM-EDS analyses – provided data about the composition and rock classification of the raw material and enabled important constraints on its possible origin

Multivariate analysis of the contents of metals in urban snow near traffic lanes in Novi Sad, Serbia

During December 2009, snow was collected at twenty two locations across the urban area of Novi Sad, directly from roads and from traffic islands near crossroads. The total metal concentration was determined for each of ten metals (Al, Ca, Cu, Fe, K, Mn, Na, Ni, Pb and Zn) using the ICP-OES analytical technique. Ni was found to have the lowest concentration (0.0265 mg dm(-3)). Na was the metal with the highest concentration (10786 mg dm(-3)), which was the consequence of sodium chloride being used as a de-icing salt on the roads. The metal with the second highest concentration at all locations was Ca; this was most likely the result of soil dust. The Spearman rank correlation coefficients between analyzed metals were calculated to determine how the concentrations of the metals were related. Cluster analysis was performed on the obtained data sets, using both the hierarchical and partitioning methods in order to identify associations among metals and/or locations. It was shown that traffic density was not the most important factor that caused the differences between the concentrations of the metals in the samples

Mineraloško-petrografska karakterizacija i moguće poreklo sirovina korišćenih za izradu abrazivnih i glačanih kamenih alatki na eneolitskom lokalitetu Masinske Njive

Mineraloško-petrografska analiza 12 uzoraka sa eneolitskog lokaliteta Masinske njive izvršena je na materijalu od kojeg su izrađene abrazivne i glačane alatke. Primenom optičkih ispitivanja i SEM-EDS metode izdvojeni su: hidrotermalno promenjeni vulkanoklastiti, koherentne facije kvarclatita i sericit-muskovit-kvarcni škriljac. Za hidrotermalno promenjene vulkanoklastite značajno je prisustvo plovućca, koje nedvosmisleno ukazuje da je postanak ovih stena vezan za eksplozivni vulkanizam. Ovakav vulkanizam nalazi se u širem području Masinskih njiva (vulkanska provincija severne Šumadije kojoj pripada Rudnik) i moguće je da materijal potiče odatle, ali je ovo neophodno potvrditi dodatnim analizama. Tri uzorka kvarclatita pokazuju, pored sitaste strukture plagioklasa, i tragove procesa flogopitizacije biotita (38,54–41.85 wt% SiO2, 16,80–20,35 wt% MgO i 9,41–12,36 wt% FeO(t), uz snižavanje sadržaja Al2O3 sa povećanjem sadržaja MgO), koji su tipični za stene kenozojskih vulkanskih kompleksa (Rudnik, Kopaonik, Golija i Rogozna). Nijedan od ovih kompleksa ne bi mogao da bude isključen kao potencijalno nalazište analiziranih kvarclatita, ali je prioritet dat Rudniku kao najbližoj lokaciji. Piroksenski varijetet kvarclatita ne pokazuje posledice procesa flogopitizacije i najverovatnije je drugačijeg porekla od ostala tri primerka kvarclatita. Poreklo sericit-muskovit-kvarcnog škriljca u ovom trenutku nije moguće odrediti zbog nedovoljnog broja uzoraka

Structural, morphological and electrical properties of multi-doped calcium phosphate materials as solid electrolytes for intermediate temperature solid oxide fuel cells

Modified solution precipitation method was used to prepare pure and doped Mg, Sr and Na hydroxyapatite type materials (CaP, CaMgP and CaSrNaP). Modification consisted of partial substitution of nitrates by acetate solution in order to achieve a more soluble and cost effective synthesis. The obtained samples were calcined at 400 degrees C (CaP400, CaMgP400 and CaSrNaP400). All powders were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). Calcined samples were densified at 1000 degrees C in an air for 3 h (CaP1000, CaMgP1000 and CaSrNaP1000). Sintered samples were characterized by XRPD, FTIR, SEM, EDS and complex impedance methods. The highest conductivity was found for the multi-doped phosphate sample (CaSrNaP1000) at 700 degrees C (1.90x10(-3)Omega(-1)cm(-1)). The corresponding activation energies of conductivity amounted to 0.31 eV in the temperature range 500-700 degrees C.Метода таложне титрације коришћена је за добијање чистог и допираног хидроксиапатита јонима Sr, Mg и Na (CaP, CaMgP and CaSrNaP). За синтезу супституисаних хидроксиапатитских материјала коришћена је модификована таложна метода у односу на досада познате методе. Због боље растворљивости и знатно веће исплативости коришћени су раствори ацетата уместо нитрата. Синтетисани материјали су калцинисани на 400 °C, а затим окарактерисани рендгенском дифракцијом, инфра црвеном спектроскопијом са Фуријеовом трансформацијом и скенирајућом електронском микроскопијом. Калцинисани узорци су синтеровани на 1000 °C са задржавањем од 3 сата у атмосфери ваздуха (CaP1000, CaMgP1000 and CaSrNaP1000). Синтеровани материјали окарактерисани су: рендгенском дифракцијом на поликристалном узорку, инфрацрвеном спекторскопијом са Фуријеовом трансформацијом и скенирајућом електронском микроскопијом са енергетско дисперзивном анализом као и методе комплексне импендансе. Највећа проводљивост добијена је на температури од 700 °C и износи 1.90×10-3 Ω-1cm-1 за мешовито допирани фосфатни материјал (CaSrNaP1000). Добијене активационе енергије проводљивости износе 0.31 eV у температурном опсегу од 500-700 ºC

Opeke VII Klaudijeve legije sa Lokaliteta Čair – Castrum (Viminacijum): preliminarna mineraloško-petrološka analiza

Izrada velike studije o opekarskoj proizvodnji VII Klaudijeve legije na teritoriji provincije Gornje Mezije započeta je pre desetak godina. Glavni logor legije i centar njene proizvodne delatnosti u periodu od kraja I do kraja IV veka nalazio se u Viminacijumu. Osim ostataka 16 peći za pečenje opeka, koji direktno svedoče o opekarskoj proizvodnji na prostoru Viminacijuma (Jevtović, Danković in press) (slika 1), do sada je prikupljena i kolekcija od oko 2000 opeka sa žigom VII Klaudijeve legije, različitih formata (imbrex, tegula, lydion, bessalis, pedalis, bipedalis)*, kao i ulomci opeka nedefinisane forme. Krajem 2019. godine započeta je i mineraloško-petrološka analiza opeka sa ciljem da se utvrde njihov sastav, karakteristike glinene paste, tehnologija proizvodnje, kao i poreklo sirovine. Prvobitna ispitivanja obuhvatila su uzorke pronađene tokom novih istraživanja legijskog utvrđenja koje se nalazi na lokalitetu Čair – Castrum**

Application of the final flotation waste for obtaining the glass-ceramic materials

This work describes the investigation of the final flotation waste (FFW), originating from the RTB Bor Company (Serbia), as the main component for the production of glass-ceramic materials. The glass-ceramics was synthesized by the sintering of FFW, mixtures of FFW with basalt (10%, 20%, and 40%), and mixtures of FFW with tuff (20% and 40%). The sintering was conducted at the different temperatures and with the different time duration in order to find the optimal composition and conditions for crystallization. The increase of temperature, from 1100 to 1480°C, and sintering time, from 4 to 6h resulted in a higher content of hematite crystal in the obtained glass-ceramic (up to 44%). The glass-ceramics sintered from pure FFW (1080°C/36h) has good mechanical properties, such as high propagation speed (4500 m/s) and hardness (10800 MPa), as well as very good thermal stability. The glass-ceramics obtained from mixtures shows weaker mechanical properties compared to that obtained from pure FFW. The mixtures of FFW with tuff have a significantly lower bulk density compared to other obtained glass-ceramics. Our results indicate that FFW can be applied as a basis for obtaining the construction materials

Non-functional Parathyroid Gland Carcinoma, a Rare Malignant Tumor of the Head and Neck

Carcinoma of the parathyroid gland is a very rare tumor of the head and neck. The largest number of carcinomas are discovered by chance.(intraoperatively, during surgery removal of the parathyroid gland are adenomas). Around 1% of the primary parathyreoidism is caused by the cancer of parathyroid glands. Only 10% of these rare tumors make up dysfunctional cancer of parathyroid glands. There have been 24 cases reported of this disease in the literature. The focus of our study is to present a case of this disease and to review the published literature to date

Distribution of major and trace elements in the Kovin lignite (Serbia)

A geochemical and mineralogical study was performed on lignite samples from the Upper Miocene Kovin deposit, hosting three coal seams. The Kovin lignite is characterized by high moisture content, medium to high ash yield, medium to high sulphur content and a relatively low gross and net calorific value. The mineralogical composition, and major and trace element contents were determined by X-ray diffraction, scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS) analyses, and inductively coupled plasma optical emission spectrometry (ICP-OES). The most abundant minerals in all lignite samples from the three coal seams are clays (illite/smectite), silicates (quartz, plagioclase), sulphates (gypsum/anhydrite) and carbonate (calcite). The other iron-rich minerals are sulphides, oxides and hydroxides (pyrite, mag-netite, haematite, and limonite). In general, mineral matter in the matrix coal consists of illite/ smectite and quartz, while xylite-rich coals, apart from illite/smectite, have a higher content of sulphates and Fe-oxide/hydroxide minerals. The lignite from the Kovin deposit is enriched in As, Cd, Co, Cr, Cu, Ga, Li, Mn, Mo, Ni, Pb, V, Zn, Gd, Tb, Er and Lu in comparison with the Clarke values for brown coals. The statistical analysis of bulk compositional data shows inorganic affinity for the majority of the major and trace elements and possible association with pyrite, illite/ smectite and calcite