Configuration X
Mostrando 1-12 de 240 artigos, teses e dissertações.
-
1. Prospects for Developing Low-Cost Optical Fiber Sensors for Liquid-Liquid Interface Detection
Abstract This work examines the prospects of a low-cost retroreflection optical sensor system for detection of the interface between two immiscible liquids, for applications in oil separation tanks. The sensor in its simplest configuration comprises a bare fiber optic tip, cleaved at an angle of 90º relative to the longitudinal fiber axis. The device tested
Journal of Microwaves, Optoelectronics and Electromagnetic Applications. Publicado em: 2022
-
2. Percutaneous and endoscopic combined treatment of bladder and renal lithiasis in mitrofanoff conduit
ABSTRACT Introduction and Objectives: Treatment of bulky lithiasis in continent and non-continent urine storage reservoirs has been widely described and debated (1). Less is known about the optimal treatment in patients with a Mitrofanoff conduit. If voiding in these patients is incomplete, leading to recurrent symptomatic bacteriuria, formation of large li
International braz j urol. Publicado em: 2022
-
3. Absolute Configuration Reassignment of Natural Products: An Overview of the Last Decade
The assignment of absolute configuration (AC) is a crucial step in the structural characterization of natural products, especially for those subjected to biological assays. Methods such as X-ray crystallography, stereocontrolled organic synthesis, nuclear magnetic resonance (NMR), and chiroptical spectroscopies are commonly used to determine the AC of chiral
J. Braz. Chem. Soc.. Publicado em: 2021-08
-
4. Absolute Configuration of (−)-Cubebin, a Classical Lignan with Pharmacological Potential, Defined by Means of Chiroptical Spectroscopy
This work describes the first determination of the absolute configuration (AC) of (−)-cubebin by means of electronic circular dichroism (ECD), supported by quantum chemical calculations. The comparison of experimental ECD with the corresponding quantum chemical prediction for the proper diastereoisomer resulted in the definitive assignment of the AC of the
J. Braz. Chem. Soc.. Publicado em: 2020-10
-
5. New Allyldithiocarbimates: Synthesis, Structure and Antifungal Activity against Phakopsora pachyrhizi and Hemileia vastatrix
Twelve tetraphenylphosphonium allyldithiocarbimates were synthesized and fully characterized by high-resolution electrospray ionization mass spectrometry (HR-ESI-MS), infrared and nuclear magnetic resonance (NMR) spectroscopies. The spectroscopic data indicated that the allyldithiocarbimate anions present Z configuration, as confirmed by X-ray crystallograph
J. Braz. Chem. Soc.. Publicado em: 2020-04
-
6. Dimensionalidade fractal e invariância de escala em circuitos elétricos AC e linhas de transmissão
Resumo A geometria fractal fascina pela capacidade de descrever formas geométricas complexas e que usualmente estão presentes no mundo real . A dimensão fractal ou de Hausdorff d é utilizada para descrever leis de invariância de escala, em que as funções autossimilares seguem uma lei da forma f ( s x ) = s d f ( x ), sendo s o fator de escala. Intim
Rev. Bras. Ensino Fís.. Publicado em: 10/01/2020
-
7. Acid-Catalyzed Z-E Isomerization of γ-Alkylidenebutenolides: An Experimental and DFT Study
The Z-E isomerization of γ-alkylidenebutenolide analogues to natural nostoclides and other natural butenolides was investigated using 1H nuclear magnetic resonance (NMR) and high performance liquid chromatography (HPLC) data as well as density functional theory (DFT) calculations at the wB97x-D/6-31G(d,p) level, including solvent effects with the polarizabl
J. Braz. Chem. Soc.. Publicado em: 2020-01
-
8. SYNTHESIS, CHARACTERIZATION, ADSORPTION AND THERMODYNAMIC STUDIES OF PURE AND BINARY CO2-N2 MIXTURES ON OXYGEN ENRICHED NANOSTRUCTURED CARBON ADSORBENTS
Abstract Oxygen enriched porous carbons have been synthesized by a nanocasting technique using mesoporous zeolite as template and epoxy resin as precursor. Characterization results show the effect of the nanocasting technique on the development of heterogeneous surface, high basicity, and high surface area of 686.37 m2g-1, beneficial for CO2 adsorption. Pure
Braz. J. Chem. Eng.. Publicado em: 09/12/2019
-
9. Mechanical and bioactivity assessment of wollastonite/PVA composite synthesized from bentonite clay
Resumo Os compósitos de vidro/polímero podem imitar a estrutura natural do osso possuindo uma configuração fibra-matriz que proporciona propriedades físicas e biológicas apropriadas. As cerâmicas de wollastonita são conhecidas por suas bioatividade e biocompatibilidade promissoras quando aplicadas na regeneração óssea. O álcool polivinílico (PVA
Cerâmica. Publicado em: 06/06/2019
-
10. Development and Characterization of PbI2 Nanoparticles for all Solid-State Flexible Supercapacitor Purposes
The development and utilization of new energy sources has been extensively studied in the world. Here, we report the development of flexible self-supported metal-free electrodes based on non-oxidized graphene multilayer (MLG) paper containing the lead iodide nanoparticles (PbI2-NPs). The PbI2-NPs was obtained and characterized by X-ray diffraction (XDR) and
Mat. Res.. Publicado em: 20/05/2019
-
11. Obtenção de austenita expandida (fase S): Nitretação por plasma em baixa temperatura x SHTPN – Parte 3
RESUMO Corpos de prova de aço inoxidável austenítico ISO 5832-1(similar ao AISI 316L, para aplicações biomédicas) apresentando camada superficial enrriquecida em nitrogênio (fase S), obtidos pelos processos de nitretação por plasma em baixa temperatura e SHTPN (Solution Heat Treatment after Plasma Nitriding -Tratamento de solubilização após nitre
Matéria (Rio J.). Publicado em: 20/05/2019
-
12. Sharp Rejection and Wide Stopband Microstrip Lowpass Filters using Complementary Split Ring Resonators
Abstract Chebyshev microstrip lowpass filters with improved performance, achieved by means of circular complementary split ring resonators (CSRR), are presented. CSRR particles exhibit frequency rejection bandwidths in the vicinity of their resonant frequencies that can be used to meliorate both selectivity and stopband in microstrip lowpass filters. Two con
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2018-03