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Full-Text Articles in Nanoscience and Nanotechnology

Study On The Use Of Mgal Hydrotalcites As Solid Heterogeneous Catalysts For Biodiesel Production, João F. Gomes Dec 2011

Study On The Use Of Mgal Hydrotalcites As Solid Heterogeneous Catalysts For Biodiesel Production, João F. Gomes

João F Gomes

This paper, reports experimental work on the use of new heterogeneous solid basic catalysts for biodiesel production: double oxides of Mg and Al, produced by calcination, at high temperature, of MgAl lamellar structures, the hydrotalcites (HT). The most suitable catalyst system studied are hydrotalcite Mg:Al 2:1 calcinated at 507 ºC and 700 ºC, leading to higher values of FAME also in the second reaction stage. One of the prepared catalysts resulted in 97.1 % Fatty acids methyl esters (FAME) in the 1st reaction step, 92.2 % FAME in the 2nd reaction step and 34 % FAME in the 3rd ...


Technical Note: Friction Factor Diagrams For Pipe Flow, Jim Mcgovern Oct 2011

Technical Note: Friction Factor Diagrams For Pipe Flow, Jim Mcgovern

Articles

This technical note describes diagrams of friction factor for pipe flow that have been prepared using, mainly, the equations that Lewis Moody used to prepare his famous diagram in 1944. The preparation of the new diagrams was prompted by the need for vector graphics versions that could be used for teaching purposes and that could be distributed freely to students and others under a Creative Commons Attribution-Share-Alike license. Using a structure very similar to that of Moody's diagram, variants with the Darcy friction factor and the Fanning friction factor have been prepared. In addition, variants have been prepared that ...


Notice On A Case Study On The Utilization Of Wind Energy Potential On A Remote And Isolated Small Wastewater Treatment Plant, João F. Gomes Aug 2011

Notice On A Case Study On The Utilization Of Wind Energy Potential On A Remote And Isolated Small Wastewater Treatment Plant, João F. Gomes

João F Gomes

Small wastewater treatment plants (WWTP) are frequently located, by necessity, in remote and isolated sites, which increases the difficulty of its energy supply. Some of them are located near the seaside, in environmental sensible zones, and due to tourism activity of these sites, seasonal effects related with population size fluctuation can occur, which can originate certain inefficiencies concerning WWTP design and energy supply. The objective of this paper is to describe a step by step procedure for evaluation of the wind potential of sites that are dependent of in-situ energy generation, as well as, a case study on the utilization ...


Seismic Characterization Of Select Engineered Nanoparticles In Essentially Saturated Glass Beads, Mohamed Nihad Rajabdeen Aug 2011

Seismic Characterization Of Select Engineered Nanoparticles In Essentially Saturated Glass Beads, Mohamed Nihad Rajabdeen

UNLV Theses, Dissertations, Professional Papers, and Capstones

A laboratory testing apparatus was developed for the study of seismic body wave propagation through nanoparticles dispersed in pore fluid that is essentially saturating glass beads. First, the responses of water-saturated glass bead specimens were studied to establish baseline signatures. Then the seismic responses in the presence of engineered nanoparticles of various concentrations dispersed in the pore fluid of the specimen chamber were studied to observe variances from baseline.

The testing apparatus incorporates piezoceramic bender elements to actuate and receive seismic body waves through a cylindrical column filled with glass beads and back-saturated at ambient pressure with liquid. The system ...


Study On The Glycerolysis Reaction Of High Free Fatty Acid Oils For Use As Biodiesel Feedstock, João F. Gomes Jan 2011

Study On The Glycerolysis Reaction Of High Free Fatty Acid Oils For Use As Biodiesel Feedstock, João F. Gomes

João F Gomes

Biodiesel is the main alternative to fossil diesel and it may be produced from different feedstocks such as semi-refined vegetable oils, waste frying oils or animal fats. However, these feedstocks usually contain significant amounts of free fatty acids (FFA) that make them inadequate for the direct base catalyzed transesterification reaction (where the FFA content should be lower than 4%). The present work describes a possible method for the pre-treatment of oils with high content of FFA (20 to 50%) by esterification with glycerol. In order to reduce the FFA content, the reaction between these FFA and an esterification agent is ...


Design Of A New Test Chamber For Evaluation Of The Toxicity Of Rubber Infill, João F. Gomes Jan 2011

Design Of A New Test Chamber For Evaluation Of The Toxicity Of Rubber Infill, João F. Gomes

João F Gomes

A test chamber was projected and built (according to ISO 16000-9 Standard) to simulate atmospheric conditions experienced by rubber infill (when applied in synthetic turf pitches) and measure accurately the airborne emissions of pollutants such as dusts and volatile organic compounds (VOC), as well as pollutants present in leacheates. It should be pointed out that standard ISO 16000-9 is only concerned with the determination of the emission of VOC from building products and furnishing (not specific of synthetic turf materials), while other standards are concerned with the emission of leacheates only. This procedure is to be considered as a technical ...


What Is A Chemical Engineer ?, João F. Gomes Jan 2011

What Is A Chemical Engineer ?, João F. Gomes

João F Gomes

No abstract provided.


On The Toxicological Effects Of Airborne Nanoparticles From Welding Processes, João F. Gomes Jan 2011

On The Toxicological Effects Of Airborne Nanoparticles From Welding Processes, João F. Gomes

João F Gomes

No abstract provided.