scholarly journals Analytical approaches for the characterization of early synthetic organic pigments for artists’ paints

2021 ◽  
pp. 106708
Author(s):  
B.N. Sundberg ◽  
R. Pause ◽  
I.D. van der Werf ◽  
A. Astefanei ◽  
K.J. van den Berg ◽  
...  
Keyword(s):  
Organic Pigments ◽  
Analytical Approaches

Monitoring of Petroleum-Related Environmental Contamination Using Fluorescence Fingerprinting

2006 ◽  
Vol 1 (2) ◽  
Author(s):  
P. Literathy ◽  
M. Quinn
Keyword(s):  
Environmental Contamination ◽  
Statistical Evaluation ◽  
Oil Pollution ◽  
Emission Spectra ◽  
Cost Effective ◽  
Petroleum Products ◽  
Danube River ◽  
Aromatic Components ◽  
Analytical Approaches

Petroleum and its refined products are considered the most complex contaminants frequently impacting the environment in significant quantities. They have heterogeneous chemical composition and alterations occur during environmental weathering. No single analytical method exists to characterize the petroleum-related environmental contamination. For monitoring, the analytical approaches include gravimetric, spectrometric and chromatographic methods having significant differences in their selectivity, sensitivity and cost-effectiveness. Recording fluorescence fingerprints of the cyclohexane extracts of the water, suspended solids, sediment or soil samples and applying appropriate statistical evaluation (e.g. by correlating the concatenated emission spectra of the fingerprints of the samples with arbitrary standards (e.g. petroleum products)), provides a powerful, cost-effective analytical tool for characterization of the type of oil pollution and detecting the most harmful aromatic components of the petroleum contaminated matrix. For monitoring purposes, the level of the contamination can be expressed as the equivalent concentration of an appropriate characteristic standard, based on the fluorescence intensities at the relevant characteristic wavelengths. These procedures are demonstrated in the monitoring of petroleum-related pollution in the water and suspended sediment in the Danube river basin

scholarly journals Numerical Modal Analysis of Vibrations in a Three-Phase Linear Switched Reluctance Actuator

2017 ◽  
Vol 2017 ◽  
pp. 1-18
Author(s):  
José Salvado ◽  
Maria do Rosário Calado ◽  
António Espírito Santo ◽  
Anna Guerman
Keyword(s):  
Control Strategies ◽  
Mode Shapes ◽  
Audio Signals ◽  
Structural Vibrations ◽  
Significant Information ◽  
Switched Reluctance ◽  
Three Phase ◽  
Linear Configuration ◽  
Analytical Approaches

This paper addresses the problem of vibrations produced by switched reluctance actuators, focusing on the linear configuration of this type of machines, aiming at its characterization regarding the structural vibrations. The complexity of the mechanical system and the number of parts used put serious restrictions on the effectiveness of analytical approaches. We build the 3D model of the actuator and use finite element method (FEM) to find its natural frequencies. The focus is on frequencies within the range up to nearly 1.2 kHz which is considered relevant, based on preliminary simulations and experiments. Spectral analysis results of audio signals from experimental modal excitation are also shown and discussed. The obtained data support the characterization of the linear actuator regarding the excited modes, its vibration frequencies, and mode shapes, with high potential of excitation due to the regular operation regimes of the machine. The results reveal abundant modes and harmonics and the symmetry characteristics of the actuator, showing that the vibration modes can be excited for different configurations of the actuator. The identification of the most critical modes is of great significance for the actuator’s control strategies. This analysis also provides significant information to adopt solutions to reduce the vibrations at the design.

scholarly journals General Analytical Schemes for the Characterization of Pectin-Based Edible Gelled Systems

2012 ◽  
Vol 2012 ◽  
pp. 1-12 ◽  
Author(s):  
Maryam Haghighi ◽  
Karamatollah Rezaei
Keyword(s):  
Image Analysis ◽  
Three Dimensional ◽  
Analytical Techniques ◽  
Physicochemical Analysis ◽  
Visual Observation ◽  
Scientific Data ◽  
Rheological Measurement ◽  
Rheological Measurements ◽  
Analytical Approaches

Pectin-based gelled systems have gained increasing attention for the design of newly developed food products. For this reason, the characterization of such formulas is a necessity in order to present scientific data and to introduce an appropriate finished product to the industry. Various analytical techniques are available for the evaluation of the systems formulated on the basis of pectin and the designed gel. In this paper, general analytical approaches for the characterization of pectin-based gelled systems were categorized into several subsections including physicochemical analysis, visual observation, textural/rheological measurement, microstructural image characterization, and psychorheological evaluation. Three-dimensional trials to assess correlations among microstructure, texture, and taste were also discussed. Practical examples of advanced objective techniques including experimental setups for small and large deformation rheological measurements and microstructural image analysis were presented in more details.

How well can we characterize human serum transformations of magnetic nanoparticles?

The Analyst ◽  
2020 ◽  
Vol 145 (4) ◽  
pp. 1103-1109 ◽  
Author(s):  
Andrei R. Timerbaev
Keyword(s):  
Magnetic Nanoparticles ◽  
Human Serum ◽  
Human Blood ◽  
Analytical Approaches

Analytical approaches emerging to fill up the gaps in the characterization of magnetic nanoparticles in human blood are critically discussed.

Simulating the climatic effects on vegetation: approaches, issues and challenges

2008 ◽  
Vol 32 (5) ◽  
pp. 543-556 ◽  
Author(s):  
Guoping Tang ◽  
Patrick J. Bartlein
Keyword(s):  
Analytical Data ◽  
Terrestrial Vegetation ◽  
Climatic Effects ◽  
Model Based ◽  
Vegetation Modelling ◽  
Vegetation Models ◽  
Data Improvement ◽  
Analytical Approaches

Vegetation modelling has been viewed as a major approach for examining the dynamics of vegetation under climatic change. However, the characterization of uncertainty of model results is still a key issue. In order to improve future model-based research, it is important to synthesize the current approaches and the issues that arise in vegetation modelling and to propose potential strategies for improving model-based research. This study first reviews the progress of vegetation models from static-equilibrium to transient-dynamic and to current coupled multi-objective vegetation models. Then, the four main sources leading to the uncertainty of model results are described, including (1) factors related to vegetation models (their structure, assumption and parameterization), (2) the data used to run a model, (3) the approaches used to validate model results, and (4) the spatiotemporal scaling issues involved in vegetation modelling. Finally, four strategies are proposed for improving future model-based research. These include improvements in the model structure and parameterization, enhancement of the quality of analytical data, improvement of the analytical approaches, and continued development of coupled dynamic vegetation models. Using a literature synthesis, this study provides researchers with a general guidance on applying vegetation models for simulating the effects of climatic variations on terrestrial vegetation.

Analytical approaches for the characterization of nickel proteome

Metallomics ◽  
2017 ◽  
Vol 9 (8) ◽  
pp. 1014-1027 ◽  
Author(s):  
Javier Jiménez-Lamana ◽  
Joanna Szpunar
Keyword(s):  
Analytical Strategies ◽  
Analytical Approaches

Analytical strategies to study the nickel proteome and their advantages and limitations.

Beyond the characterization of wine aroma compounds: looking for analytical approaches in trying to understand aroma perception during wine consumption

2011 ◽  
Vol 401 (5) ◽  
pp. 1497-1512 ◽  
Author(s):  
Carolina Muñoz-González ◽  
Juan J. Rodríguez-Bencomo ◽  
M. Victoria Moreno-Arribas ◽  
M. Ángeles Pozo-Bayón
Keyword(s):  
Aroma Compounds ◽  
Wine Aroma ◽  
Wine Consumption ◽  
Analytical Approaches

Analytical Approaches for Characterization of Teeth Whitening Gels Based on Natural Extracts

2017 ◽  
Vol 752 ◽  
pp. 24-28
Author(s):  
Miuţa Filip ◽  
Laura Silaghi-Dumitrescu ◽  
Doina Prodan ◽  
Codruța Sarosi ◽  
Marioara Moldovan ◽  
...  
Keyword(s):  
Medicinal Plant ◽  
Organic Acids ◽  
Phenolic Acids ◽  
Vanillic Acid ◽  
Mobile Phase ◽  
Coumaric Acid ◽  
Natural Extracts ◽  
Analytical Approaches ◽  
Rutin And Quercetin

The present study reports the analytical approaches for characterization of teeth whitening gels based on natural extracts of fruits and medicinal plant. High performance liquid chromatography (HPLC) with UV detection were used for identification and quantification of (oxalic, citric, tartaric, malic, succinic and fumaric acids), flavonoids (catechin, epicatechin, rutin and quercetin) and phenolic acids (vanillic acid, p-coumaric acid, ferullic acid) from studied gels samples used for teeth whitening. The organic acids were used as active agent with action in tooth discoloration and stain removal. Organic acids were separated through a Carbosep Coregel 87H3 column at 35°C and detection at 214 nm. The mobile phase was the sulphuric acid 0.005 M solution. The total quantity of organic acids of these gel samples was determined. The action of flavonoids have controlled dental caries and inhibited plaque formation. Separation of flavonoids and phenolic acids was carried out on Lichrosorb RP-C18 column at 40 oC and detection at 290 nm. The mobile phase was a mixture of methanol and solution 0.1% formic acid in a gradient elution. The flavonoids, catechin, epicatechin, rutin and quercetin and phenolic acids, vanillic acid, p-coumaric acid, ferullic acid, were determined quantitative in the teeth whitening gels on natural extracts of fruits and medicinal plant.

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