Helium
Mostrando 1-12 de 215 artigos, teses e dissertações.
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1. A Physical Study to Explain Response Differences between the BID and FID Detectors for PAHs and Pesticides
The dielectric barrier discharge ionization detector (BID) is one of the most modern detectors commercially available for gas chromatography (GC). Its technology based on the sample ionization through the energy released from the helium plasma generation process gives it the ability to act as a universal detector and a greater response to various types of co
Journal of the Brazilian Chemical Society. Publicado em: 2022
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2. Verification of atmospheric plasma irradiation as an alternative control method for Tribolium castaneum (Herbst)
Resumo Plasma de radiofrequência, plasma de RF, tem sido empregado em diversas aplicações industriais. Experimentos de laboratório foram conduzidos para determinar o potencial de plasma de RF no controle de Tribolium castaneum (Herbst). Foram examinados nesse estudo três variáveis de tratamento: (1) plasma de hélio ou argônio; (2) dois níveis de pot
Braz. J. Biol.. Publicado em: 21/10/2019
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3. Reduction of Aqueous Ag+ Steered by Electrochemical Plasma: Connecting the Bulk pH Variation with the Reaction Pathways for Hydrated Electrons
Reduction of silver cations followed by nanoparticle (Ag-NPs) synthesis is a model process to understand the reduction mechanism induced by a discharge over an aqueous surface, termed electrochemical plasma. This work aims at studying the silver reduction reaction steered by electrochemical plasma in the presence of other chemically active plasma-related int
J. Braz. Chem. Soc.. Publicado em: 23/05/2019
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4. The performance of the (U+Th)/He thermochronology laboratory at UNESP Rio Claro, Brazil
We have developed the first laboratory for (U-Th-Sm)/He thermochronology measurements in South America. Helium is measured using a high-sensitivity magnetic sector mass spectrometer (GVI-Helix-SFT) and a double focusing single collector inductively coupled plasma mass spectrometer (Thermo Scientific ELEMENT2) is used for U, Th and Sm determinations. Repeated
An. Acad. Bras. Ciênc.. Publicado em: 21/03/2019
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5. Influence of sintering temperature on the development of alumina membrane shaped by centrifugal casting for gas separation
Abstract The development of ceramic membranes for the most diverse separation processes has gained high visibility, mainly due to their better performance in harsh environments in comparison to polymeric materials. Among the different techniques used to prepare tubular ceramic membranes, the centrifugal casting (CC) is interesting for obtaining highly homoge
Cerâmica. Publicado em: 2019-01
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6. Comparison of Methods for Determining the Water Absorption of Glazed Porcelain Stoneware Ceramic Tiles
This work evaluated the water absorption of glazed porcelain stoneware ceramic tiles using three different methods. Two methods were based on a procedure of boiling in water, specified by standards ISO 10545 and ASTM C373, and the third was the vacuum method proposed by the standard ISO 10545. The three products produced under the three different firing cond
Mat. Res.. Publicado em: 17/11/2017
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7. Focal cryotherapy: step by step technique description
ABSTRACT Introduction and objective: Focal cryotherapy emerged as an efficient option to treat favorable and localized prostate cancer (PCa). The purpose of this video is to describe the procedure step by step. Materials and methods: We present the case of a 68 year-old man with localized PCa in the anterior aspect of the prostate. Results: The procedure
Int. braz j urol.. Publicado em: 2017-10
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8. EFFECTS OF SINTERING TEMPERATURE ON THE PERFORMANCE OF SrSc0.1Co0.9O3-δOXYGEN SEMIPERMEABLE MEMBRANE
Abstract Our study investigates the influence of sintering temperature on the microstructure (grain size distribution, grain boundary length), electrical conductivity, and oxygen permeation properties of permeation membranes. For this purpose, SrSc0.1Co0.9O3-δ samples with different microstructures were prepared by varying the sintering temperature from 110
Braz. J. Chem. Eng.. Publicado em: 2015-09
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9. Efeito da ativação mecânica de uma formulação de talco/caulim/alumina sobre o mecanismo e a cinética de formação de cordierita
In this study, the influence of mechanical activation by intensive ball milling of a stoichiometric mixture of talc, kaolin, and alumina on the mechanism and kinetics of cordierite (2MgO·2Al2O3·5SiO2) formation was evaluated. The raw materials were characterized by chemical analysis, X-ray diffraction (XRD), laser diffraction, and helium pycnometry. The ki
Quím. Nova. Publicado em: 2014-04
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10. Effects of pneumoperitoneum with carbon dioxide and helium on renal function and morphology in rats
PURPOSE: To evaluate the effects of pneumoperitoneum with carbon dioxide and helium on renal function and morphology in a rat model. METHODS: Twenty four rats were randomized into three groups (n=8): gasless insufflation ('open', Pressure=0 mmHg), carbon dioxide pneumoperitoneum at 12 mmHg, and helium pneumoperitoneum at 12 mmHg; all lasting 90 minutes.. A c
Acta Cir. Bras.. Publicado em: 2013-07
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11. Correlation between bursting pressure and breaking strength in colonic anastomosis
PURPOSE: To investigate the correlation between bursting pressure and breaking strength on the 7th postoperative day following left colonic anastomosis in rats. METHODS: Seventy rats were randomly divided into seven groups of ten animals each. All of the animals underwent segmental resection of the left colon and end-to-end anastomosis. The animals in groups
Acta Cir. Bras.. Publicado em: 2013-06
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12. Removal of Cadmium(II) and Lead(II) ions from aqueous phase on sodic bentonite
This paper describes the adsorption of Cd2+and Pb2+ions using sodic bentonite clay type Fluidgel modified. The Fluidgelbefore and after chemical modification and thermal activation was characterized by different techniques including X-ray diffraction, thermal analysis, Fourier transform infrared, surface area, helium pycnometry, cation exchange capacity and
Mat. Res.. Publicado em: 28/01/2013