Crystal Field
Mostrando 1-12 de 156 artigos, teses e dissertações.
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1. Linking gemology and spectral geology: a case study of elbaites from Seridó Pegmatite Province, Northeastern Brazil
Abstract reflectance spectroscopy is a fast tool for mineral identification and classification. We conducted spectral characterization of elbaite samples (n = 30) from Seridó Pegmatite Province, Borborema Province, NE Brazil, using a FieldSpec portable instrument and geochemical data from electron probe microanalysis. Visual interpretation of reflectance sp
Braz. J. Geol.. Publicado em: 13/05/2019
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2. FOTOCATÁLISE MEDIADA POR TiO2 NO ESTADO NANOPARTICULADO: REVISÃO DA REATIVIDADE PELO CONCEITO DE TRAPS E ALGUMAS APLICAÇÕES EM QUÍMICA ANALÍTICA
TiO2 has been used as a white pigment and studied since the first decades of the XX century for the undesirable chalking of outdoor paintings exposed to sunlight. Since the first report of Honda and Fujishima (1972) of the water splitting by the harvesting of sunlight on a n-type single crystal TiO2 electrode, the engagement of researchers with the field has
Quím. Nova. Publicado em: 02/05/2019
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3. Synthesis and Characterization of Non-Linear Optical Crystal of Manganese Mercury Thiocyanate Glycol Monomethyl Ether
The design and synthesis of organic nonlinear optical (NLO) crystals are a promising area of current research in materials science. Organic materials are found to possess better non linear optical properties when compared to inorganic materials. Recently, there has been a widespread interest in the metal-organic coordination compounds, which are a combinatio
Mat. Res.. Publicado em: 30/11/2017
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4. Protein-species quantitative venomics: looking through a crystal ball
Abstract In this paper we discuss recent significant developments in the field of venom research, specifically the emergence of top-down proteomic applications that allow achieving compositional resolution at the level of the protein species present in the venom, and the absolute quantification of the venom proteins (the term “protein species” is used he
J. Venom. Anim. Toxins incl. Trop. Dis. Publicado em: 06/07/2017
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5. Sodium Chloride Crystallization by Electric Discharge in Brine
Electrical discharges in liquids are currently used to synthesize nanoparticles. The plasma-liquid interaction is complex, where parameters such as electric field, ion charges and other species present are important. In order to understand the mechanism of crystallization, mother liquor (saturated solution of NaCl, MgCl2 and KCl) was used to study the effect
Mat. Res.. Publicado em: 06/07/2017
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6. Anatomy and histochemistry of leaves and stems of Sapium glandulosum
Abstract Sapium belongs to Euphorbiaceae family and comprises 23 species. Sapium glandulosum (L.) Morong is popularly known in Brazil as "pau-leiteiro" and "leitosinha" and it is used in traditional medicine to cicatrisation. Its leaf extracts have shown analgesic, anti-inflammatory and antibacterial activities. The preliminary set of pharmacognostic tools u
Rev. bras. farmacogn.. Publicado em: 2017-06
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7. Evaluation of a Thermochromic Liquid Crystal for Use as a Temperature Sensor for Components of Electrical Systems
Connectors used in electrical power distribution systems should allow the passage of electricity continuously and without interruption. However, this does not always occur due to failure caused by improper assembly and/or corrosion of the materials employed, which reflects the quality of service. Notable among the new detection technologies that have been st
Mat. Res.. Publicado em: 22/05/2017
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8. Self-Organization in Ionic Liquids: From Bulk to Interfaces and Films
In this contribution we present an overview on the relation between the complex structure of ionic liquids (ILs) and its impact in the field of surface science. The results herein described result mainly from modeling and simulation work carried out at Centro de Química Estrutural, Universidade de Lisboa, complemented in some cases by experimental results o
J. Braz. Chem. Soc.. Publicado em: 2016-02
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9. Estudio de estructuras de cis- y trans-estilbeno mediante microscopiade fuerza atómica
ABSTRACTNanotechnology is a multidisciplinary field that emerged in recent years due to the development of tools to "see", study and manipulate matter at atomic and molecular levels. Stilbene and some of its derivatives are organic molecules found in nature, which have chemical structures of interest in nano-fabrication of molecular machine building blocks (
Matéria (Rio J.). Publicado em: 2015-09
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10. Dimensions and refractive index estimates of deeply buried optical waveguides in Lithium Fluoride
A recursive procedure is applied to the measured near-field profiles of buried optical waveguides recorded in a lithium fluoride (LiF) crystal by femtosecond laser pulses in order to estimate the core dimensions and the refractive index increase. Albeit the waveguides transversal section geometry is quite complex it is possible to obtain the horizontal and v
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2014-06
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11. CONTRIBUIÇÃO AO ESTUDO DE CAMPO CRISTALINO E TRANSIÇÕES 4f-4f EM SISTEMAS CONTENDO LANTANÍDEOS. / CONTRIBUTION TO THE STUDY OF CRYSTAL AND FIELD 4F-4F TRANSITIONS IN SYSTEMS CONTAINING LANTHANIDES.
A theoretical study of the interactions between the 4f electrons in lanthanide ions (Ln3 +) with the chemical environment was made using crystal field theory. The main effects were studied: change in position of the berycentre of the energy levels of the free ion, maximum splitting of the J level and contribution to 5D0-7F0 transition of Eu3+ ion. Use of sec
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 18/09/2012
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12. SYSTEMATIC STUDY OF CRYSTAL FIELD PARAMETERS IN COMPLEX ION EU3 +. / ESTUDO SISTEMÁTICO DE PARÂMETROS DE CAMPO CRISTALINO EM COMPLEXOS DE ÍONS EU3+.
Neste trabalho foram utilizados e comparados dois modelos e um método, a fim de estipular a melhor maneira de descrever as propriedades espectroscópicas dos complexos contendo íons Ln3+, a saber, o modelo eletrostático de cargas pontuais (PCEM), o modelo de recobrimento simples (SOM) e o método dos vizinhos equivalentes (MENN). Foram previstos parâmetr
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 19/07/2012