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Showing 1 to 20 of 107 for “"Microextraction"”.
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DEVELOPMENT OF ELECTRO-ENHANCED MICROEXTRACTION TECHNIQUES
ELECTRO-ENHANCED MICRO EXTRACTIONS ARE SAMPLE PREPARATION TECHNIQUES WHICH ARE BASED ON THE USE OF AN ELECTRICAL POTENTIAL APPLIED DURING THE EXTRACTION PROCESS TO ENHANCE ITS EXTRACTION EFFICIENCY. THE DRIVING FORCE AFFECTED BY ELECTRICAL POTENTIAL FOR ANALYTES EXTRACTION IN DIFFERENT SAMPLE …
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Extending the Limits of Solid Phase Microextraction
<p>Solid phase microextraction (SPME) is a solventless extraction technique that combines sample preparation and sample introduction into a gas chromatograph into a single step. For the past 20 years, solid-phase micro-extraction (SPME) has been used in numerous fields such as: food analysis, …
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Microextraction and gas chromatographic determination of organotin compounds /
… was to examine possibilities of liquid-liquid microextraction methods for fast and efficient extraction of organotin compounds (OTC) and to prepare and apply the most appropriate technique for the analysis of aqueous samples. In real samples OTC exist in cationic form, are non-volatile and …
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Solid phase microextraction of amino-dinitrotoluenes in tissue.
… environmental matrixes and tissues. Solid phase microextraction (SPME) was used to extract ADNTs (amino-dinitrotoluenes) from tissue as a potential method to investigate the recalcitrance of metabolically-generated ADNTs versus absorbed ADNTs. Tubifex tubifex was allowed to metabolize TNT into …
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Extraction of alcohols from gasoline using solid phase microextraction (SPME)
… of EtOH in gasoline by solid phase microextraction (SPME). The major problem in quantifying EtOH in gasoline is the coelution of hydrocarbons with EtOH. There have been several approaches to solve this problem; among the chromatographic ones, three major types have been proposed: (1) …
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Hollow fibre liquid phase microextraction of pharmaceuticals in water and Eichhornia crassipes
Submitted in fulfilment of the requirements for the Degree of Master of Applied Sciences in Chemistry, Durban University of Technology, Durban, South Africa, 2019.
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Forensic sample analysis using supercritical fluid extraction coupled with solid phase microextraction
A third of adults in the UK admit to using controlled substances at least once hi their lives and the most commonly abused drug was found to be cannabis, followed by the opiates and ecognine derivatives. Forensic laboratories are continually trying to reduce the turnaround time for samples …
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Use of solid-phase microextraction to detect semiochemicals in synthetic and biological samples
… to determine the effectiveness of solid-phase microextraction (SPME) at identifying semiochemicals (chemical messengers) in both synthetic and biological samples. Solid-phase microextraction, an alternative to traditional sample fractionation, employs specialized polymer fibers to detect …
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Detection of Illicit Drugs in Various Matrices Via Total Vaporization Solid-Phase Microextraction
In Headspace Solid-Phase Microextraction (Headspace SPME), a sample is heated to encourage a portion of the analyte into the headspace of a vial. A coated fiber is introduced into the sample headspace and the analyte is adsorbed onto the fiber coating. Total Vaporization Solid-Phase Microextraction …
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Development, investigation and application of new microextraction systems for determination of volatile aromatic hydrocarbons /
A new solid phase microextraction system composed of nanotubes coating fixed on a stainless steel support is suggested. Thermal stability and selectivity of the system was examined. It was determined that the system can be used for direct and headspace extraction of volatile aromatic hydrocarbons. …
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Development of Total Vaporization Solid Phase Microextraction and Its Application to Explosives and Automotive Racing
Pipe bombs are a common form of improvised explosive device, due in part to their ease of construction. Despite their simplistic nature, the lethality of pipe bombs should not be dismissed. Due to the risk of harm and their commonality, research into the pipe bomb deflagration process and …
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Predicting the bioavailability and toxicity of hydrophobic pesticides using bioassays and a solid phase microextraction approach
… important factor in risk assessment. Solid phase microextraction (SPME) is an equilibrium partitioning technique that has been successfully used to estimate body residues by measuring the freely dissolved chemical concentration and assessing chemical bioavailability in exposure media. The …
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Profile of Missouri Norton wine aroma using solid phase microextraction of headspace, gas chromatography-olfactometry, mass spectrometry
… was performed using headspace solid-phase microextraction (HS-SPME) and identified by a trained panel. The samples were then diluted to determine the most important odor active compounds, resulting in thirty one compounds responsible for the nine most common descriptors of diluted Norton …
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Naujų mikroekstrakcijos sistemų kūrimas, tyrimas ir taikymas lakių aromatinių angliavandenilių nustatymui /
A new solid phase microextraction system composed of nanotubes coating fixed on a stainless steel support is suggested. Thermal stability and selectivity of the system was examined. It was determined that the system can be used for direct and headspace extraction of volatile aromatic hydrocarbons. …
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Advances in solid phase microextraction for the analysis of volatile compounds in explosives, tire treatments, and entomological specimens
<p>Solid phase microextraction is a powerful and versatile technique, well-suited to the analysis of numerous samples of forensic interest. The exceptional sensitivity of the SPME platform, combined with its adaptability to traditional GC-MS systems and its ability to extract samples with minimal …
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Advances in Solid Phase Microextraction for the Analysis of Volatile Compounds in Explosives, Tire Treatments, and Entomological Specimens
Solid phase micro-extraction is a powerful and versatile technique, well-suited to the analysis of numerous samples of forensic interest. The exceptional sensitivity of the SPME platform, combined with its adaptability to traditional GC-MS systems and its ability to extract samples with minimal …
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Sample Preparation/Concentration for Trace Analysis in GC/MS (A study of solid phase microextraction and headspace sampling)
Solid Phase Microextraction (SPME) associated with Microwave Assisted Extraction (MAE)<sup>(1-3)</sup> , on-line headspace derivatization <sup>(4-6)</sup> and the selectivity of different SPME coatings <sup>(7)</sup> were studied. Trace amounts of Veltol ®, Veltol Plus® and short chain fatty acids …
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The Effect of Wine Matrix Ingredients on 3-Alkyl-2-methoxypyrazines Measurements by Headspace Solid-Phase Microextraction (HS-SPME)
… was investigated with solid-phase microextraction (SPME) and capillary gas chromatography, using a nitrogen phosphorus detector. Changes in the recovery of 3-ethyl-, isopropyl-, sec-butyl-, and isobutyl-2-methoxypyrazines from the static headspace of synthetic wine matrices spiked …
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Characterization of human expired breath by solid phase microextraction and analysis using gas chromatography-mass spectrometry and differential mobility spectrometry
… to this problem. Tedlar bags and solid-phase microextraction were used for breath sampling and concentration prior to analysis. Four fiber coatings were evaluated with respect to selectivity and sensitivity; extraction time, gas chromatography temperature programming, and sample storage …
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