Aplicação Da Espectroscopia Raman Na Caracterização De Minerais Pertencentes a Uma Geocoleção

Abstract

RAMAN SPECTROSCOPY APPLICATION IN THE CHARACTERIZATION OF PERTAINING MINERALS OF A GEOCOLLECTION. Lots of Educational Institutions hold their own geocollection due to its utility and versatileness in the practical formation of new generations of skillful professionals in many areas of Science and Technology. The Geoscience laboratory of the Federal University of São Carlos has a collection of minerals used in engineering, mineralogy and other technological courses ministered to undergraduates of different programs. Three samples of this collection were identified using Raman spectroscopy. The analysis carried out in this work enabled the characterization of the major mineral components in the samples as well as the identification of other minor crystalline phases present in the sample. It is important to notice that this information could not be obtained using the regular analyses of mineral properties, such as density, streak, hardness, brightness, cleavage, among others. As a result, the samples A170801 and A170802 were characterized as being mainly calcite (CaCO 3) and spodumene (LiAlSi 2 O 6), respectively. On the other hand, sample A170803 show the presence of three different minerals: graphite (C), quartz (SiO 2) and muscovite [KAl 2 (Si 3 Al)O 10 (OH,F) 2 ].

Investigação Do Solvatocromismo E Ionocromismo Do Corante Azul Do Nilo Através Das Espectroscopias Raman, Infravermelho E Uv-Vis

“…A aplicação de técnicas espectroscópicas vibracionais na investigação de diferentes espécies químicas de relevância ambiental, biológica, na construção civil e em patrimônio histórico-cultural tem crescido significantemente nos últimos anos, pois são técnicas que apresentam elevada sensibilidade e não necessitam de grande quantidade amostra. Como exemplos recentes, o emprego da microscopia Raman na identificação de minerais em rochas, 18 na análise de pele humana associada à quimiometria para estudo da ação de produtos de cuidados pessoais, 19 na caracterização de cimento preparado a partir do reuso de escória de alto forno, 20 na identificação de microplásticos poluentes de ambientes aquáticos e águas minerais, 21 na determinação da penetração de corantes em camadas protetoras de óxido de alumínio poroso, 22 etc. As análises empregando a espectroscopia Raman são rápidas, não necessitam de preparação de amostra e apresentam um espectro característico para cada substância, sendo chamada de impressão digital da molécula.…”

Raman spectroscopy in the quality analysis of dairy products: A literature review

“…Depending on the region of the electromagnetic spectrum in which the incident energy is found, different types of transition occur, such as the electronic transitions that occur in the ultraviolet or visible region of the electromagnetic spectrum, the rotational transitions defined in the microwave region, and the molecular translational and vibrational transitions that are located in the infrared region. [ 9 ]…”

“…Depending on the region of the electromagnetic spectrum in which the incident energy is found, different types of transition occur, such as the electronic transitions that occur in the ultraviolet or visible region of the electromagnetic spectrum, the rotational transitions defined in the microwave region, and the molecular translational and vibrational transitions that are located in the infrared region. [9] The main techniques of vibrational spectroscopy are infrared absorption and Raman scattering; the first occurs in the middle and far infrared region of the electromagnetic spectrum, and the second comprises the elastic and inelastic scattering resulting from the incidence of light in the near or visible infrared. These spectroscopic methods investigate the transitions that occur in the sample molecules due to the interaction of an oscillating electric field from the incident electromagnetic radiation.…”

Tangerine peel ashes applied as green catalyst: a biorefinery‐based approach for biodiesel production

“…In the region between 400 and 700 cm −1 , it was possible to see peaks normally attributed to external vibrations of the C━O bond of the CO 3 2− (CaCO 3 ), and vibrations of the Si━O━Si bond. 38,39 At 1099.70 cm −1 , there is a peak assigned to the stretching of the Si━O bond for non-bridged oxygen and Table 2. Data of basicity, specific surface area (S BET ) and pore volume of tangerine 'Ponkan' (TPC) catalysts.…”

“…S BET (m 2 g −1 ) Pore volumes (cm 3 g −1 ) TPC7 (CaCO 3 ). 39 At 976.58, 1055.73 and 1138.58 cm −1 , there are peaks that could be due to antisymmetric stretching of the Si━O bond, with bridged and non-bridged oxygen. 40 The peak at 1044.19 cm −1 is attributed to the vibration of the C━O bond of the CO 3 2− of the K 2 CO 3 group.…”