Bourdeau PL Articles | Environmental XPRT

Optical properties of normal and 'giant' multishell CdSe quantum dots for potential application in material science

The results on the optical properties of the normal and 'giant' multi-shell nanocrystal quantum dots (QDs) as CdSe/ZnS, CdSe/ZnSe/ZnS and CdSe/CdS/ZnS are presented for further improvement of the QDs quality as quantum yields (QY), photobleaching and blinking. The photoluminescence (PL) of CdSe core, monoshell and multishell QDs was studied to understand the radiative and non-radiative relaxation ...

Jan. 24, 2011

By Inderscience Publishers

Characterisation of self–ordered porous anodic alumina by X–ray diffraction line profile analysis

We report on the structural properties of porous anodic alumina (PAA) film produced by the anodisation technique under different annealing temperatures. X–ray diffraction (XRD) and photoluminescence (PL) measurements were performed. For the samples annealed in oxygen, decreases in the PL intensity and blueshift of the PL peak energy are observed with increasing annealing temperatures. The ...

Oct. 16, 2014

By Inderscience Publishers

InAs nanostructures on polar GaAs surfaces

InAs nanostructures were grown by molecular beam epitaxy on GaAs (111)B and (211)B substrates at various growth temperatures between 450°C and 530°C. Their structural properties were studied by atomic force microscopy. For the (111)B grown nanostructures, the formation of self-aligned InAs quantum dashes was revealed, which in some cases took the form of nanowires. In the (211)B case, the shape ...

Dec. 1, 2008

By Inderscience Publishers

Photoluminescence spectroscopy study of excited states in In x Ga 1–x As-capped InAs quantum dots

This study reports on photoluminescence (PL) and PL excitation (PLE) spectroscopy studies of excited state transitions in In x Ga 1–x As-capped InAs quantum dots (QDs). InAs self-assembled QDs were grown on GaAs (001) wafers using 2.5 mono layer (ML) InAs deposition via molecular beam epitaxy. GaAs-capped QDs showed PL peak position at 1.182 μm at 78 K with a narrow full width at half ...

Jun. 3, 2013

By Inderscience Publishers

Simultaneous UV-Vis spectrophotometric quantification of ternary basic dye mixtures by partial least squares and artificial neural networks

One of the main difficulties in quantification of dyes in industrial wastewaters is the fact that dyes are usually in complex mixtures rather than being pure. Here we report the development of two rapid and powerful methods, partial least squares (PLS-1) and artificial neural network (ANN), for spectral resolution of a highly overlapping ternary dye system in the presence of interferences. To ...

Sep. 13, 2016

By IWA Publishing

Formation of photoluminescent properties inherent to silicon quantum dots

The analysis of original works devoted to preparation and investigation of nanocrystalline silicon (nc-Si) films containing Si quantum dots (QDs) that exhibit photoluminescence (PL) within the range 1.4 – 3.2 eV at room temperature is presented. Thin films were prepared by pulse laser deposition (PLD). Offered by authors doping these nc-Si films with gold in the growing process provided ...

Jan. 19, 2006

By Inderscience Publishers

Determination of water supply sources in the Barcelona distribution system by UV spectrophotometry and PLS

A new method for the water source apportionment of the Barcelona (Spain) water distribution system is proposed. The method is based on the combined use of UV spectrophotometric measurements in the wavelength from 190–230 nm, and multivariate data analysis using the Partial Least Squares (PLS) chemometric method. From the differences in the organic matter content of the different water sources and ...

Mar. 1, 2011

By IWA Publishing

Near-infrared spectroscopic assessment of contamination level of sewage

We examined the use of near infrared (NIR) spectroscopy as a rapid technique for the evaluation of sewage quality. Influent water samples, primary sedimentation tank water samples, and final effluent water samples were collected from sewage treatment facilities in Nagoya, Japan and their NIR spectra obtained. Partial least squares (PLS) models for total phosphate (TP), total nitrogen (TN), ...

Apr. 1, 2010

By IWA Publishing

Application of multivariate methods in the monitoring of marine environment: simultaneous determination of bromide, bicarbonate, nitrate and sulphide in seawater by ultraviolet spectroscopy

In this paper we present a new ultraviolet (UV) spectroscopic method for the simultaneous and reagentless determination of bromide, bicarbonate, nitrate and sulphide ions in artificial seawater solutions, applicable to the monitoring of the marine environment. We collected the UV spectra of artificial seawater samples with salinity between 8 and 45 psu, having known concentrations of these ...

May 22, 2013

By Inderscience Publishers

Optical properties of LiF:Mg,Cu,P nanorods

Nanorods of LiF:Mg,Cu,P synthesized by the chemical co-precipitation technique have been investigated for their optical properties. Photoluminescence (PL) emission and excitation spectra and UV-visible absorption spectrum have been investigated in this paper. PL emission spectrum shows a wide emission band located at the range 350 nm-450 nm along with emerging of a sharp intense band at 376 nm. ...

Aug. 10, 2009

By Inderscience Publishers

Predicting influent PO4 using a multivariate soft sensor. Proceedings ICA2017

Abstract: A method for implementing a multivariate Partial Least Squares (PLS) soft sensor is discussed with a focus on sensor robustness. Practical aspects of implementation are examined including handling of missing or poor input data, sensor and data diagnostics, automated soft sensor calibration, and on-line sensor operation. Proof-of-concept examples are drawn using data from a simulated ...

Jan. 1, 2017

By inCTRL Solutions Inc.

Modelling of Human Acute Toxicity from Physicochemical Properties and Non-Vertebrate Acute Toxicity of the 38 Organic Chemicals of the MEIC Priority List by PLS Regression and Neural Network

Abstract :Linear and non-linear modelling of human acute toxicity (as human lethal concentrations; HLCs) of the 38 organic chemicals from the 50 priority compounds of the Multicentre Evaluation ofIn VitroCytotoxicity (MEIC) programme was investigated. The models obtained were derived either from a set of 23 physicochemicals properties of the compounds of from their acute toxicities to five ...

Jan. 8, 2020

By Microbiotests Inc.

Impact of gypsum applied to grass buffer strips on reducing soluble p in surface water runoff

The threat of P transport from land applied manure has resulted in water quality concerns. Research was conducted to evaluate gypsum as a soil amendment applied to grass buffer strips for reducing soluble P in surface runoff. A simulated concentrated flow was created in an established tall fescue (Festuca arundinacea Schreb.) pasture. Poultry litter (PL) was applied at a rate of 250 kg N ha–1 to ...

Aug. 20, 2008

By Soil Science Society of America (SSSA)

Field study on N2O emission from subsurface wastewater infiltration system under variable loading rates and drying-wetting cycles

In this field study, the impacts of influent loadings and drying-wetting cycles on N2O emission in a subsurface wastewater infiltration (SWI) system were investigated. N2O emitted under different operation conditions were quantified using static chamber and gas chromatograph techniques. N2O conversion rate decreased from 6.6 ± 0.1% to 2.7 ± 0.1% with an increase in hydraulic loading (HL) from ...

Jul. 3, 2017

By IWA Publishing

Well monitoring for a water supplier - Case study

The municipality company, in city of Luebek, Germany, provides potable water for approximately 120,000 households, all pumped from more than 30 wells. These wells have water levels as deep as 160 meters. The water levels of these groundwater wells must be measured with the highest possible accuracy. Previously, the pressure probe's analogue output signals (4…20mA) that had been used ...

Jan. 18, 2017

By OTT HydroMet

Use of multivariate calibration models based on UV-Vis spectra for seawater quality monitoring in Tianjin Bohai Bay, China

A series of ultraviolet-visible (UV-Vis) spectra from seawater samples collected from sites along the coastline of Tianjin Bohai Bay in China were subjected to multivariate partial least squares (PLS) regression analysis. Calibration models were developed for monitoring chemical oxygen demand (COD) and concentrations of total organic carbon (TOC). Three different PLS models were developed using ...

May 18, 2015

By IWA Publishing

Intellectual capital and business performance in the Portuguese banking industry

Previous empirical studies confirm that intellectual capital has a significant and substantive impact on performance. The purpose of this research is to examine the inter-relationships and interactions among intellectual capital components and business performance in the Portuguese banking industry. The concept of relational capital was extended to include 'stakeholder orientation' items. Model ...

Jul. 14, 2008

By Inderscience Publishers

Negotiated Agreements as a vehicle for Policy Learning

The paper evaluates to which extent that different designs of Voluntary Agreements (VAs) can work as catalysts for Policy Learning (PL) and thus contribute to improved policy design and management processes. Through a literature study, it is found that VAs in the form of Negotiated Agreements (NAs) are more successful in promoting PL than other types of VAs that have less focus on the ...

Jun. 30, 2010

By Inderscience Publishers

Study of photoluminescence quenching and DC conductivity measurements in polymer-SWNT composite films for various SWNT concentrations

Conducting polymer-SWNT composite films have a high potential in the area of photovoltaic devices and light emitting diodes (LEDs). SWNTs have high electron affinity and high mobility for electrons. As a result of this, the separation of photoinduced charges in the solar cell is very fast and efficient. For LEDs, the polymer-SWNT composite films act as efficient electron transporting layer (ETL). ...

May 20, 2009

By Inderscience Publishers

Elaboration and characterisation of (Al, V) co-doped nanosized zinc oxide aerogel

In this study, we report the elaboration of vanadium-aluminium co-doped ZnO nanoparticles prepared by a sol-gel processing technique. Aluminium and vanadium doping concentrations of 1 at% and 10 at% respectively have been investigated. The obtained nanopowder was characterised by various techniques such as transmission electron microscopy (TEM), X-ray diffraction (XRD) and photoluminescence (PL) ...

Aug. 10, 2009

By Inderscience Publishers