Double Resonance
Mostrando 1-12 de 197 artigos, teses e dissertações.
-
1. Evaluation of pulmonary nodules by magnetic resonance imaging sequences: which sequence will replace computed tomography?
SUMMARY OBJECTIVE: This study aimed to determine the role of magnetic resonance imaging in minimizing radiation exposure, especially in the follow-up of pulmonary nodules. METHODS: Patients who applied to our hospital between April 2013 and August 2018 for various reasons and had lung-mediastinal dynamic magnetic resonance imaging and thoracic computed tom
Revista da Associação Médica Brasileira. Publicado em: 2022
-
2. Aqueous Extract of Cumaru (Dipteryx odorata) Seeds as Corrosion Inhibitor for Mild Steel in Hydrochloric Acid Solution
The corrosion inhibition of mild steel by aqueous extract of cumaru (Dipteryx odorata) seeds and its high molecular weight fraction (HMWF) was investigated in 1 mol L-1 HCl solution. The study was carried out through gravimetric essays, open circuit potential measurements, anodic and cathodic polarization curves and electrochemical impedance analyses, as wel
J. Braz. Chem. Soc.. Publicado em: 2021-02
-
3. Metamaterial-Fractal-Defected Ground Structure Concepts Combining for Highly Miniaturized Triple-Band Antenna Design
Abstract In this paper, a novel method is proposed to increase the gain and radiation efficiency of a compact patch antenna. By employing a combination of three efficient techniques, we have developed a multi-resonance L-DGS antenna with a high gain of 5 dB and an efficiency of 99.6%. Furthermore, a novel compact Double Negative metamaterial unit cell and it
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2020-12
-
4. Intercalation of Apocarotenoids from Annatto (Bixa orellana L.) into Layered Double Hydroxides
Synthetic conditions were evaluated to intercalate norbixin into layered double hydroxides (LDH). Norbixin was isolated from a hydrosoluble commercial annatto extract. LDH samples comprising M2+/Al3+ (M = Mg, Zn) were synthesized by coprecipitation and characterized by X-ray diffraction, thermal analysis coupled to mass spectrometry, vibrational spectroscopi
J. Braz. Chem. Soc.. Publicado em: 2020-11
-
5. APCI(+)FT-ICR MS Analysis of Hydrocarbons Using Isooctane as Ionizing Reagent - A Comparison with HTGC-FID, GC×GC-MS and NMR
Hydrocarbons present in saturated fractions of crude oils can be assessed by atmospheric pressure chemical ionization (APCI) using small hydrocarbons as ionizing reagents in a Fourier transform ion cyclotron resonance mass spectrometer (FT-ICR MS). In this work, five paraffin standards of different average molar mass distributions (Mw) were easily ionized by
J. Braz. Chem. Soc.. Publicado em: 08/04/2019
-
6. Synthesis of Spiro-Pyrrolidinyloxindoles by Oxidative Rearrangement of N-Acyltetrahydro-β-carbolines Using an Oxone/Aqueous Acetone Mixture
Spiro-pyrrolidinyl-2-oxindoles were prepared by the oxidative rearrangement of Na-acetyl-1,2,3,4-tetrahydro-β-carbolines (THBC) using dimethyldioxirane generated in situ. The Na-acetyl THBC substrates were obtained by Pictet-Spengler and acyl-Pictet-Spengler reactions of L-tryptophan methyl ester, followed by Na-acetylation. The stereoselectivity of the oxi
J. Braz. Chem. Soc.. Publicado em: 2019-01
-
7. Novos surfactantes alquil poliglicosídicos à base de amilose extraída da batata inglesa (Solanum tuberosum L.)
Alkyl polyglycosides (APGs) are new biodegradable surfactants, non-toxic, synthesized from abundant renewable sources, potentially more appropriate than anionic surfactants. A range of glycosides denoted APG-Cy was synthesized by the Köenig-Knorr reaction using C10, C16 and C18 alcohols and derived from the degradation of amylose from English potato. The mo
Quím. Nova. Publicado em: 2017-04
-
8. Transverse Motions of Rectangular Plates Resting on Elastic Foundation and Under Concentrated Masses Moving at Varying Velocities
AbstractThis study concerns the dynamic characteristics of a prestressed isotropic, rectangular plate continuously supported by an elastic foundation and carrying accelerating mass M. Closed form solutions of the governing fourth order partial differential equations with variable and singular coefficients are presented. For the two-dimensional plate problem,
Lat. Am. j. solids struct.. Publicado em: 2015-07
-
9. Injeção roncoplástica: comparação entre etanol 50% e oleato de etanolamina 5% no tratamento do ronco / Injection snoreplasty: comparison between ethanol and ethanolamine oleate in snoring treatment
BACKGROUND: Snoring affects a significant portion of the population and the treatment is a challenge, because there are many options and the choice should be individualized. Among various palatal procedures for the treatment of snoring and sleep apnea, the injection snoreplasty (IS) has emerged as an economic alternative for selected cases. OBJECTIVES: To ev
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 20/04/2011
-
10. Petroleômica por espectrometria de massas de altíssima resolução e exatidão : informação química precisa e seletiva através de novas estratégias de processamento e visualização de dados / Petroleomics by ultra-high resolving power and accuracy mass spectrometry : selective and accurate chemical information by new procedures of data processing
Amostras de petróleos bruto e derivados podem ser caracterizadas com altíssima rapidez e eficiência através da técnica denominada petroleômica por espectrometria de massas por ressonância ciclotrônica de íons e transformada de Fourier (FT-ICR MS). Milhares de marcadores polares são resolvidos e identificados em questão de 6 ~ 7 minutos com muita a
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 17/02/2011
-
11. Desenvolvimento de bobinas de RF transmissoras e receptoras do tipo phased arrays para experimentos de imagens por ressonância magnética em ratos / Development of RF transmitter coils and receivers NMR phased arrays for magnetic resonance imaging experiments on rats
Experimentos de Imagens por Ressonância Magnética (IRM) em pequenos animais, assim como em humanos, exigem um conjunto especifico de bobinas de Radiofrequência (RF) para maximizar ambos a homogeneidade de campo durante a transmissão e a Relação Sinal Ruído (RSR) durante a recepção. As geometrias mais comuns de bobinas transmissoras utilizadas em sis
Publicado em: 2011
-
12. Caracterização de óleos vegetais e petróleo por espectrometria de massas em condições ambiente e com alta exatidão e resolução / Characterization of vegetable oils and petroleum by mass spectrometry in ambient conditions and with high-accuracy and resolution
A caracterização química de óleos de forma rápida, eficiente e com mínimo preparo de amostras é um desafio para a química analítica moderna. Este estudo abrangeu a caracterização química de 15 amostras de óleos vegetais e 6 amostras de petróleo, e demonstrou a versatilidade da técnica de espectrometria de massas (MS) nesta área. A caracteriza
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 30/09/2010