23 documents found, page 1 of 3
Investigating mechanical properties of hot mix asphalt containing iron ore flot...
Soncim, Sérgio Pacífico; Oliveira, Jonas Henrique de Carvalho; Almeida, Marconi Oliveira de; Oliveira, Carlos Augusto de Souza; Belotti, Fernanda MariaStudies involving the use of iron ore tailings from the beneficiation process in different market niches are increasingly necessary due to the large environmental damage caused by their disposal in dams, since they are waste generated in high volumes and which have low economic value for mining companies The main purpose of this study was to investigate mechanical properties of hot mix asphalt mixture containin...
A vibrational spectroscopic study of the phosphate mineral vantasselite Al4(PO4...
Frost, Ray Leslie; Cipriano, Ricardo Augusto Scholz; Belotti, Fernanda Maria; López, Andrés; Theiss, Frederick L.We have studied the phosphate mineral vantasselite Al4(PO4)3(OH)3 9H2O using a combination of SEM with EDX and Raman and infrared spectroscopy. Qualitative chemical analysis shows Al, Fe and P. Raman bands at 1013 and 1027 cm 1 are assigned to the PO43 m1 symmetric stretching mode. The observation of two bands suggests the non-equivalence of the phosphate units in the vantasselite structure. Raman bands at 1051...
A vibrational spectroscopic study of the anhydrous phosphate mineral sidorenkit...
Frost, Ray Leslie; López, Andrés; Cipriano, Ricardo Augusto Scholz; Belotti, Fernanda Maria; Xi, YunfeiSidorenkite is a very rare low-temperature hydrothermal mineral, formed very late in the crystallization of hyperagpaitic pegmatites in a differentiated alkalic massif (Mt. Alluaiv, Kola Peninsula, Russia). Sidorenkite Na3Mn(PO4)(CO3) is a phosphate–carbonate of sodium and manganese. Such a formula with two oxyanions lends itself to vibrational spectroscopy. The sharp Raman band at 959 cm 1 and 1012 cm 1 are as...
SEM, EDX and vibrational spectroscopic study of the phosphate mineral ushkovite...
López, Andrés; Cipriano, Ricardo Augusto Scholz; Frost, Ray Leslie; Belotti, Fernanda MariaThe mineral ushkovite has been analyzed using a combination of electron microscopy with EDX and vibrational spectroscopy. Chemical analysis shows the mineral contains P, Mg with very minor Fe. Thus, the formula of the studied ushkovite is Mg3 2+(PO4)2 8H2O. The Raman spectrum shows an intense band at 953 cm 1 assigned to the m1 symmetric stretching mode. In the infrared spectra complexity exists with multiple a...
The molecular structure of the borate mineral szaibelyite MgBO2(OH) : a vibrati...
Frost, Ray Leslie; Cipriano, Ricardo Augusto Scholz; López, Andrés; Belotti, Fernanda MariaWe have studied the borate mineral szaibelyite MgBO2(OH) using electron microscopy and vibrational spectroscopy. EDS spectra show a phase composed of Mg with minor amounts of Fe. Both tetrahedral and trigonal boron units are observed. The nominal resolution of the Raman spectrometer is of the order of 2 cm 1 and as such is sufficient enough to identify separate bands for the stretching bands of the two boron is...
Vibrational spectroscopic characterization of the phosphate mineral ludlamite (...
Frost, Ray Leslie; Xi, Yunfei; Cipriano, Ricardo Augusto Scholz; Belotti, Fernanda MariaThe objective of this work is to analyze ludlamite (Fe,Mn,Mg)3(PO4)2_4H2O from Boa Vista mine, Galiléia, Brazil and to assess the molecular structure of the mineral. The phosphate mineral ludlamite has been characterized by EMP-WDS, Raman and infrared spectroscopic measurements. The mineral is shown to be a ferrous phosphate with some minor substitution of Mg and Mn. Raman bands at 917 and 950 cm_1 are assigned...
Infrared and Raman spectroscopic characterization of the carbonate mineral huan...
Frost, Ray Leslie; López, Andrés; Cipriano, Ricardo Augusto Scholz; Xi, Yunfei; Belotti, Fernanda MariaRaman spectroscopy complimented with infrared spectroscopy has been used to study the rare earth based mineral huanghoite with possible formula given as BaCe(CO3)2F and compared with the Raman spectra of a series of selected natural halogenated carbonates from different origins including bastnasite, parisite and northupite. The Raman spectrum of huanghoite displays three bands are at 1072, 1084 and 1091 cm^-1 a...
Vibrational spectroscopy of the mineral meyerhofferite CaB3O3(OH)5 H2O - an ass...
Frost, Ray Leslie; López, Andrés; Xi, Yunfei; Cipriano, Ricardo Augusto Scholz; Costa, Geraldo Magela da; Belotti, Fernanda MariaMeyerhofferite is a calcium hydrated borate mineral with ideal formula: CaB3O3(OH)5_H2O and occurs as white complex acicular to crude crystals with length up to _4 cm, in fibrous divergent, radiating aggregates or reticulated and is often found in sedimentary or lake-bed borate deposits. The Raman spectrum of meyerhofferite is dominated by intense sharp band at 880 cm_1 assigned to the symmetric stretching mode...
Raman, infrared and near-infrared spectroscopic characterization of the herderi...
Frost, Ray Leslie; Cipriano, Ricardo Augusto Scholz; López, Andrés; Xi, Yunfei; Queiroz, Camila de Siqueira; Belotti, Fernanda MariaNatural single-crystal specimens of the herderite–hydroxylherderite series from Brazil, with general formula CaBePO4(F,OH), were investigated by electron microprobe, Raman, infrared and near-infrared spectroscopies. The minerals occur as secondary products in granitic pegmatites. Herderite and hydroxylherderite minerals show extensive solid solution formation. The Raman spectra of hydroxylherderite are characte...
A vibrational spectroscopic study of the phosphate mineral lulzacite Sr2Fe2+(Fe...
Frost, Ray Leslie; López, Andrés; Belotti, Fernanda Maria; Xi, Yunfei; Cipriano, Ricardo Augusto ScholzThe mineral lulzacite from Saint-Aubin des Chateaux mine, France, with theoretical formula Sr2Fe2+(Fe2+,Mg)2Al4(PO4)4(OH)10 has been studied using a combination of electron microscopy with EDX and vibrational spectroscopic techniques. Chemical analysis shows a Sr, Fe, Al phosphate with minor amounts of Ga, Ba and Mg. Raman spectroscopy identifies an intense band at 990 cm_1 with an additional band at 1011 cm_1....