Search results for "010401 analytical chemistry"
showing 10 items of 1284 documents
A Low-Cost Multi-Modal Auditory-Visual-Tactile Framework for Remote Touch
2020
International audience; Haptic technology for human augmentation provides gains in ability for different applications, whether the aim is to enhance "disabilities" to "abilities", or "abilities" to "super-abilities". Commercially-available devices are generally expensive and tailored to specific applications and hardware. To give researchers a haptic feedback system that is economical, customisable, and fast to fabricate, our group developed a low-cost immersive haptic, audio, and visual experience built by using off-the-shelf (COTS) components. It is composed of a vibrotactile glove, a Leap Motion sensor, and an head-mounted display, integrated together to provide compelling immersive sens…
Efficient Hybrid Emergency Aware MAC Protocol for Wireless Body Sensor Networks
2018
International audience; In Body Sensor Networks (BSNs), two types of events should be addressed: periodic and emergency events. Traffic rate is usually low during periodic observation, and becomes very high upon emergency. One of the main and challenging requirements of BSNs is to design Medium Access Control (MAC) protocols that guarantee immediate and reliable transmission of data in emergency situations, while maintaining high energy efficiency in non-emergency conditions. In this paper, we propose a new emergency aware hybrid DTDMA/DS-CDMA protocol that can accommodate BSN traffic variations by addressing emergency and periodic traffic requirements. It takes advantage of the high delay …
Managing sensor data streams in a smart home application
2020
A challenge in developing an ambient activity recognition system for use in elder care is finding a balance between the sophistication of the system and a cost structure that fits within the budgets of public and private sector healthcare organisations. Much activity recognition research in the context of elder care is based on dense networks of sensors and advanced methods, such as supervised machine learning algorithms. This paper presents the data processing aspects of an activity recognition system based on a simpler, knowledge-based unsupervised approach, designed for a sparse network of sensors. By structuring sensor data management as a streaming system, we provide a simple programmi…
Sample Preparation to Determine Pharmaceutical and Personal Care Products in an All-Water Matrix: Solid Phase Extraction
2020
© 2020 by the authors.
Evaluating the protecting effects of two consolidants applied on Pietra di Lecce limestone: A neutronographic study
2020
Abstract In this work a combined laboratory-based and neutronographic investigation was carried out on a type of limestone, known as Pietra di Lecce stone, widely used in Italian Baroque as construction material. The limestone was treated with two different commercially-available coatings, namely nanosilica and nanolime, and artificially weathered by salt crystallization and temperature/relative humidity jumps. The aim was to provide an experimental evidence of the protective and consolidating effectiveness of the two treatments by looking at the water absorption process occurring inside the pore network of the analyzed stones. The analysis of the wetting front position revealed significant…
Ethyl Hexanoate Transfer Modeling in Carrageenan Matrices for Determination of Diffusion and Partition Properties.
2007
; Aroma compound properties in food matrices, such as volatility and diffusivity, have to be determined to understand the effect of composition and structure on aroma release and perception. This work illustrates the use of mass transfer modeling to identify diffusion and partition properties of ethyl hexanoate in water and in carrageenan matrices with various degrees of structure. The comparison of results obtained with a diffusive model to those obtained with a convective model highlights the importance of considering the appropriate transfer mechanism. Modeling of the preliminary experimental steps ensures correct estimation of the conditions for the main aroma release step. The obtaine…
Magnetic particle mixing with magnetic micro-convection for microfluidics
2015
International audience; In this paper we discuss the magnetic micro-convection phenomenon as a tool for mixing enhancement in microfluidics systems in cases when one of the mis-cible fluids is a magnetic particle colloid. A system of a water-based magnetic fluid and water is investigated experimentally under homogeneous magnetic field in a Hele-Shaw cell. Subsequent image analysis both qualitatively and quan-titatively reveals the high enhancement of mixing efficiency provided by this method. The mixing efficiency dependence on the magnetic field and the phys-ical limits is discussed. A suitable model for a continuous-flow microfluidics setup for mixing with magnetic micro-convection is als…
Climate signals in δ13C of wood lignin methoxyl groups from high-elevation larch trees
2016
Abstract In this study, a barely used method to measure δ13C values from lignin methoxyl groups (δ13Cmethoxyl) of tree‐rings is applied to high alpine larch trees to test their potential as a climate proxy. Thirty-seven larch trees (Larix decidua Mill.) were sampled at a tree line site near Simplon Village in the Valais/Switzerland. Samples were used to measure tree-ring width, and from five individuals, δ13Cmethoxyl was determined at annual resolution from 1971 to 2009, and at pentadal resolution from 1747 to 2009. The physiological tree responses to increasing atmospheric CO2 concentration since 1850 and the corresponding decrease in δ13C (Suess effect) were corrected using a range of pub…
Complete1H,13C{1H}, and31P NMR spectral parameters of some pyrophosphates
2017
The 1 H, 13 C{1 H}, and 31 P NMR spectral parameters of some pyrophosphates were determined in CDCl3 . The most complicated 1 H spectrum can be solved fully only as (A3 MN)R6 XX'R6 '(MNA3 )', where R6 (= -N(CH3 )2 ) is coupled only to phosphorus (X). Second-order coupling between phosphorus was found and solved with iterative analysis. A signal shape of one of the carbon resonance cannot be explained only with couplings. Explanation for exceptional shape was searched from molecular modeling results. Copyright © 2017 John Wiley & Sons, Ltd.
Portable microwave assisted extraction: An original concept for green analytical chemistry.
2013
International audience; This paper describes a portable microwave assisted extraction apparatus (PMAE) for extraction of bioac-tive compounds especially essential oils and aromas directly in a crop or in a forest. The developed procedure, based on the concept of green analytical chemistry, is appropriate to obtain direct in-field information about the level of essential oils in natural samples and to illustrate green chemical lesson and research. The efficiency of this experiment was validated for the extraction of essential oil of rosemary directly in a crop and allows obtaining a quantitative information on the content of essential oil, which was similar to that obtained by conventional m…