Search results for "Direct analysi"

Room temperature acid sonication ICP-MS multielemental analysis of milk

2005

Abstract Room temperature acid sonication of milk samples is proposed as a fast alternative methodology for the determination of the total content of 45 elements (Li, Al, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Rb, Sr, Y, Mo, Ag, Cd, In, Sn, U, Sb, Te, Cs, Ba, Hg, Pb, Bi, Th, La, Ce, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, Lu, Hf and Ta) in milk by inductively coupled plasma mass spectrometry (ICP-MS). The aforementioned procedure involves a 10 min sample pre-treatment. Measurements were made in quantitative and semiquantitative (Totalquant ® ) modes of analysis using Rh as internal standard and Be, Ge, Tb and Re for internal calibration of the equipment in the semiquantitative mode. The…

Conjugation reactions of polyaromatic quinones to mono- and bisglutathionyl adducts: Direct analysis by fast atom bombardment mass spectrometry

1988

The conjugation products of several reactive quinones with glutathione have been identified by fast atom bombardment mass spectrometry. Appropriate conditions have been developed which enabled the direct, dynamic mass spectral analysis of spontaneous, as well as glutathione transferase catalysed conjugation reactions. Applications to a series of quinones provided the direct detection and differentiation of the formation of mono- and bisglutathionyl adducts between regioisomeric quinone substrates in that only 1,4-quinones yielded bisglutathionyl adducts, which were not observed for the 1,2-isomers.

Flow Injection Analysis– F ourier Transform Infrared Spectrometry ( FIA / FT ‐ IR )

2001

The sections in this article are Advantages and Historical Perspective of the Use of FIA in FT-IR Direct Analysis of Samples by FIA/FT-IR FIA/FT-IR Determinations after Liquid Extraction FIA/FT-IR Determinations after Solid-Phase Extraction Enzymatic Analysis by FIA/FT-IR Vapor Generation FT-IR New Developments

Direct Analysis of Samples

2012

La cattedrale di Troina: prima sperimentazione architettonica Normanna in Sicilia

2019

International audience; At the time of the conquest of Sicily, ruled by Arabs for two centuries, Roger de Hauteville placed in Troina his first capital (1062), made the town becoming episcopal see. For this purpose, he founded in the town a cathedral church, too. However, the original aspect of the building changed deeply because of earthquakes: collapse and significant alterations occurred between the 15th and 18th centuries, causing the current architectural form. In this paper, thanks to the study of sources, the direct analysis of the building and the interpretation of the new acquired informations, some aspects of building's architectural history are clarified; in addition, a new hypot…

Green extraction techniques in green analytical chemistry

2019

Abstract Green analytical chemistry concept, involving the development of analytical methodologies with an environmental concern, encourages the use of direct analysis to avoid any sample treatment that involves energy and reagent consumption and generation of wastes. However, the determination of target analytes at trace concentration levels or in complex matrices frequently requires previous extraction, pre-concentration, or clean-up steps offering thus, additional possibilities for greening classical methods. So, a green evaluation of alternative extraction techniques to currently used ones for the extraction of solid, liquid, and gaseous samples has been carried out in this study. Moreo…

The Use of Amberlite Adsorbents for Green Chromatography Determination of Volatile Organic Compounds in Air

2012

Passive samplers have been widely used for volatile organic compounds determination. Following the green chemistry tendency of the direct determination of adsorbed compounds in membrane-based devices through using head space direct chromatography analysis, this work has evaluated the use of Amberlite XAD-2, XAD-4, and XAD-16 adsorbents as a filling material for passive samplers. Direct analysis of the membranes by HS-GC-MS involves a solvent-free method avoiding any sample treatment. For exposed membranes, recoveries ranged from 10% to 203%, depending on the compound and adsorbent used. The limit of the detection values ranged from 1 to 140 ng per sampler. Acceptable precision and sensitivi…

The Determination of Carbohydrates by High-Performance Anion-Exchange Chromatography Coupled with Pulsed Amperometric Detection (HPAEC-PAD)

2021

Chromatography techniques are widely used to separate, identify, and quantify molecules depending on their physicochemical properties. Standard methods range from simple size exclusion to separation based on affinity or ion exchange. Here, we present a method for the direct analysis of carbohydrates in Magnaporthe oryzae using high-performance anion-exchange chromatography (HPAEC) coupled with pulsed amperometric detection (PAD). The combination of HPAEC with PAD provides the highest selectivity and sensitivity with minimal sample preparation and cleanup time. Utilizing our HPAEC-PAD approach, we obtain reliable and highly reproducible determination of carbohydrates produced as osmotic stre…

Direct analysis of power-split CVTs: A unified method

2018

Abstract This paper provides a fast kinematic analysis method for compound power-split CVTs, which consents to identify their functional parameters. Such parameters permit the assessment of power flows, torques and efficiency, and the design of equivalent transmissions by the use of a recently published mathematical model. The same method can easily address either simpler or more complex transmissions by mean of kinematic equivalent parameters, without the need to arrange separate systems of equations. As a case study, we performed the kinematic analysis of the “Voltec” multi-mode GM transmission.

Effects of mechanical deformation on electronic transport through multiwall carbon nanotubes

2017

Abstract The effects of mechanical deformation on the electron transport behavior of carbon nanotubes (CNTs) are of primary interest due to the enormous potential of nanotubes in making electronic devices and nanoelectromechanical systems (NEMS). Moreover it could help to evaluate the presence of defects or to assess the type of CNTs that were produced. Conventional atomistic simulations have a high computational expense that limits the size of the CNTs that can be studied with this technique and a direct analysis of CNTs of the dimension used in nano-electronic devices seems prohibitive at the present. Here a novel approach was designed to realize orders-of-magnitude savings in computation…