Column
Mostrando 25-36 de 4309 artigos, teses e dissertações.
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25. Dimensional design of the barometric leg of a flotation column: a key to operational stability
Abstract The inefficiency in controlling the slurry/froth interface level of a scavenger column flotation stage was severely impairing the process performance of an iron mining company, increasing the iron content in the tailings to levels above 20% and, consequently, not meeting the company's iron recovery and pellet feed production targets. Based on mass b
REM, Int. Eng. J.. Publicado em: 2020-03
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26. CONSTRUÇÃO DE MINI FORNO PARA FUNCIONALIZAÇÃO TÉRMICA DE FASES ESTACIONÁRIAS MONOLÍTICAS
The present work describes a mini oven built to be applied in the preparation of monolithic stationary phase through the thermal polymerization approach. The developed device was successfully tested for functionalization of monolithic stationary phase in the internal surface of the silica capillary column fused with gold nanoparticles.
Quím. Nova. Publicado em: 2020-03
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27. A Selective Gas Chromatography-Selected Ion Monitoring Mass Spectrometry (GC-MS/SIM) Method to Determine Polychlorinated Biphenyls in Fuller’s Earth
Polychlorinated biphenyls (PCBs) are carcinogenic to humans and can be found in Fuller’s earth used for the regeneration of used transformer oil. This work describes a highly selective gas chromatographic-selected ion monitoring mass spectrometric method (GC-MS/SIM) for the simultaneous determination of three Aroclor PCB congener mixtures (1242, 1254, and
J. Braz. Chem. Soc.. Publicado em: 2020-03
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28. CHEMICAL REGENERATION OF BONE CHAR ASSOCIATED WITH A CONTINUOUS SYSTEM FOR DEFLUORIDATION OF WATER
Abstract Sources of fluoride contaminated water are found around the world and their treatment is required before human consumption. This paper contributes to advances in the use of bone-char as an adsorbent for fluoride, associating steps of chemical regeneration and fluoride adsorption in continuous systems, thereby making feasible the multiple use of the
Braz. J. Chem. Eng.. Publicado em: 13/01/2020
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29. Performance of Avocado Seed Activated Carbon as Adsorbent for Highly Sensitive Determination of Cd Using a Flow Injection System Online Coupled to TS-FF-AAS
A flow-injection preconcentration system using detection by the thermospray flame furnace atomic absorption spectrometry (FIA-TS-FF-AAS) is proposed. Cd2+ are adsorbed on avocado seed activated carbon (ASAC) packed into a cylindrical mini-column and eluted using HCl solutions for the detection system. A 25–1 fractional factorial and Doehlert matrix design
J. Braz. Chem. Soc.. Publicado em: 2020-01
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30. Simultaneous determination of anti-diabetic drugs
A novel reverse phase, isocratic HPLC method is described to separate five anti-diabetic drugs i.e., glimepiride, metformin, sitagliptin, rosiglitazone and pioglitazone. Nucleosil C18 analytical column was used as stationary phase, while mobile phase consisted of acetonitrile:phosphate buffer: methanol (40/40/20, v/v) pH 2.0. Effluent was monitored at a flow
Braz. J. Pharm. Sci.. Publicado em: 20/12/2019
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31. IS THERE A RELATION BETWEEN HELYBACTER PYLORI AND INTESTINAL METAPLASIA IN SHORT COLUMN EPITELIZATION UP TO 10 MM IN THE DISTAL ESOPHAGUS?
RESUMO Racional: A presença de metaplasia intestinal no esôfago distal (esôfago de Barrett) é importante doença precursora do adenocarcinoma. O conhecimento sobre os fatores de risco e o processo pelo qual ela se desenvolve é importante e o Helicobacter pylori (HP) pode contribuir para esse desenvolvimento. Objetivo: Analisar o impacto do HP na mucos
ABCD, arq. bras. cir. dig.. Publicado em: 20/12/2019
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32. SEPARATION OF SULFUR-CONTAINING COMPOUNDS FROM DIESEL BY OXIDATION FOLLOWED BY SOLVENT EXTRACTION IN A SINGLE DROP COLUMN
Abstract Oxidative desulfurization (ODS) is an attractive complementary or alternative process for the hydrodesulfurization (HDS) process due to advantages such as mild operating conditions. In the ODS process, the sulfur-containing compounds are oxidized first to polar sulfoxide and sulfone products and then these polar compounds are separated using solvent
Braz. J. Chem. Eng.. Publicado em: 09/12/2019
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33. ENERGY AND EXERGETIC EVALUATION OF THE MULTICOMPONENT SEPARATION OF PETROCHEMICAL NAPHTHA IN FALLING FILM DISTILLATION COLUMNS
Abstract Multicomponent separation of synthetic petrochemical naphtha (hexane, cyclohexane, toluene and xylene) was carried out in a falling film distillation sequence with heat supply using a vapor chamber (thermosyphon). Tests were carried out by varying feed flow rate and temperatures of the feed and the vapor chamber in two ways of heat supply: isotherma
Braz. J. Chem. Eng.. Publicado em: 09/12/2019
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34. ESTIMATION OF PARAMETERS AND STATES USING A BAYESIAN PARTICLE FILTER FOR THE SULFATE ION ADSORPTION PROCESS IN A FIXED BED COLUMN
Abstract Ensuring that industrial effluents meet quality standards to be released into water bodies is still one of the major environmental concerns. Liquid phase adsoption in fixed bed collumns is one of the most known treatments. Measurements are needed to monitor the process. However, as they are often corrupted by noise from the measuring equipment, perf
Braz. J. Chem. Eng.. Publicado em: 09/12/2019
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35. 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
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36. Index of severity of musculoskeletal symptoms in keyboardists
Resumo Introdução: Os profissionais da música podem apresentar desconforto musculoesquelético como dor, fraqueza, dormência e formigamento devido à realização de movimentos repetitivos. Objetivo: Avaliar a frequência e o índice de severidade dos sintomas musculoesqueléticos (SM) em músicos tecladistas. Método: Trabalho do tipo transversal, co
Fisioter. mov.. Publicado em: 09/12/2019