Hrgc High Resolution Gas Chromatography
Mostrando 1-9 de 9 artigos, teses e dissertações.
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1. Diterpenes from marine brown alga Dictyota guineensis (Dictyotaceae, Phaeophyceae)
The crude extract of the marine brown alga Dictyota guineensis was analyzed by high-resolution gas chromatography-mass spectrometry (HRGC-MS). Five diterpenes were identified: dictyol E (the most abundant diterpene), dictyotadiol, dictyoxide, isopachydictyol A and pachydictyol A, all diterpenes from the chemical group I, i.e., mainly prenylated derivatives o
Revista Brasileira de Farmacognosia. Publicado em: 29/05/2012
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2. Hidrólise do óleo de Azadirachta indica em água subcrítica e determinação da composição dos triacilglicerídeos e ácidos graxos por cromatografia gasosa de alta resolução a alta temperatura e cromatografia gasosa de alta resolução acoplada à espectrometria de massas
The development of modern analytical tools plays an important role in quality control. The main purpose of this study was to explore the use of subcritical water as a versatile analytical tool, employed simultaneously as a reagent and solvent, as well as the application of high temperature-high resolution gas chromatography (HT-HRGC) to develop a procedure f
Química Nova. Publicado em: 2010
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3. Analysis of direct mono, di, triacylglyceride into biodiesel by high resolution gas chromatography: the resolution ANP 42 and its extensions / Análise direta de mono, di e triacilglicerídeos em biodiesel por cromatografia gasosa de alta resolução: resolução ANP 42 e suas extensões
Biodiesel is chemically defined as fatty acid mono-alkyl esters derived of vegetable oils, animal fats or discarded greases. The process more commonly employed for biodiesel production is transesterification catalyzed by base. The quality control of the produced biodiesel is essential for its use as fuel. The National Agency of Petroleum (ANP) establishes di
Publicado em: 2008
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4. Análise por cromatografia gasosa de BTEX nas emissões de motor de combustão interna alimentado com diesel e mistura diesel-biodiesel (B10)
This paper describes the procedures for analysing pollutant gases emitted by engines, such as volatile organic compounds (benzene, toluene, ethylbenzene, o-xylene, m-xylene and p-xylene) by using high resolution gas chromatography (HRGC). For IC engine burning, in a broad sense, the use of the B10 mixture reduces drastically the emissions of aromatic compoun
Química Nova. Publicado em: 2008
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5. Simulação numérica da migração de elementos metálicos e do monômero -caprolactama de embalagens poliméricas irradiadas para simulantes de alimentos / SIMULATION STUDY OF -CAPROLACTAM MONOMER AND METALLIC ELEMENTS MIGRATION FROM IRRADIATED POLYMERIC PACKAGING INTO FOOD SIMULANTS
For decades migration study of chemical compounds from packaging into food, such as metals, residual monomers and additives, is a very important issue, concerning public health and minimize chemical contamination. In this work, it was done irradiations of packagings taken in contact with food simulant, and it was studied this migration through a mathematical
Publicado em: 2008
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6. SÃntese de biodiesel de Ãleo de nabo forrageiro empregando metanol supercrÃtico
The biodiesel produced in this experiment was obtained from radish oil. We used two methods, one with catalyst-free supercritical methanol and the other with 5% zeolite heterogeneous catalyst (based on its total mass). To obtain biodiesel purification we used column adsorption chromatography (AOCS Cd 11c-93) from which was observed that the catalyst-free sup
Publicado em: 2007
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7. CGAR E CGAR-EM na análise dos constituintes químicos isolados do extrato hexanico de Sebastiania argutidens (Euphorbiaceae)
The fractionation column with SiO2 of the hexane extract of Sebastiania argutidens (Euphorbiaceae) yielded fractions containing hydrocarbons, carboxylic acids, sterols and pentacyclic triterpenes. Besides, one fraction showed the presence of several methyl esters, including four uncommon long chain palmitate esthers as minor components. The characterization
Química Nova. Publicado em: 2002-02
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8. Estado da arte da cromatografia gasosa de alta resolução e alta temperatura
The developments in stationary phase synthesis and capillary column technology, have opened new perspectives in analysis of high molecular mass compounds (³600 daltons) and thermolabile organic compounds by High Temperature High Resolution Gas Chromatography (HT-HRGC). HT-HRGC is a new analytical borderline and its application to
Química Nova. Publicado em: 2000-06
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9. Occupational exposure to polychlorinated dibenzo-p-dioxins and dibenzofurans in a magnesium production plant.
OBJECTIVES--The production of magnesium is a well known source of both aliphatic and aromatic chlorinated compounds, among others the polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). The aim of this study was to establish whether increased concentrations of PCDDs and PCDFs could be found in the blood of workers in a magnes