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Wyniki wyszukiwania dla: high-pressure liquid chromatography
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Effects of osmotic and high pressure stress on expression of virulence factors among Enterococcus spp. isolated from food of animal origin
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Identification of novel psychoactive substances 25B-NBOMe and 4-CMC in biological material using HPLC-Q-TOF-MS and their quantification in blood using UPLC–MS/MS in case of severe intoxications
PublikacjaThis paper describes cases of poisoning caused by new psychoactive substances such as: 25BNBOMe (2-(4-bromo-2,5-dimethoxyphenyl)-N-[(2-methoxyphenyl)methyl]ethanamine) and 4-CMC (1-(4-chlorophenyl)-2-(methylamino)-1-propanone). The analytical procedure includes rapid and selective method for the extraction and determination of 4-CMC and 25B-NBOMe in blood samples using UPLC–MS/MS technique. To the best of our knowledge,this is...
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Analysis of volatile fraction selected hybrid fruits using chromatographic techniques
PublikacjaAt present, "healthy eating" is gaining in popularity. Many people associate this term with eating plenty of vegetables and fruits. The basic elements influencing the selection of fruit are their appearance and smell. Of course, their origin and impact on human health are also very important. In recent years, exotic fruits have become increasingly accessible, making them gaining popularity, even among Poles. You can also meet plants...
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A natural deep eutectic solvent - protonated L-proline-xylitol - based stationary phase for gas chromatography
PublikacjaThe paper presents a new kind of stationary phase for gas chromatography based on deep eutectic solvents (DES) in the form of a mixture of L-proline (protonated with hydrochloric acid) as a hydrogen bond acceptor (HBA) and xylitol as a hydrogen bond donor (HBD) in a molar ratio of HBA:HBD 5:1. DES immobilized on a silanized chromatographic support was tested by gas chromatography (GC) in order to determine its resolving power for...
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Method development and validation for optimized separation of quercetin derivatives in selected Potentilla species using high-performance thin-layer chromatography photodensitometry method
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Analysis of pesticide residue in tomato samples using analytical protocol based on application of QuEChERS technique and GC-ECD system
PublikacjaQuEChERS sample preparation method was used for the determination of 10 pesticides and their metabolites in tomato samples, coupled to gas chromatography with electron capture detector (GCECD). The experimental parameters including oven temperature program, amount of the sample and purifying agent were optimized. The GC-ECD method was validated in terms of linearity, selectivity and recovery. The limits of detection (LODs) of the...
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Funcionality assessment of Citrus Hysteria peel as a protective barrier using gas chromatography
PublikacjaThe aim of this study was to analyse the volatile fractions of fruit peel and pulp using two-dimensional gas chromatography technique coupled with mass spectrometry. The isolation of the compounds was achieved by microextraction to the stationary phase from the headspace of the sample (HS-SPME). Mass spectrometry with time-of-flight analyser (TOF-MS) was used to identify the chemical compounds. There are no reports in the literature...
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Determination of thiocyanate (biomarkers of ETS) and other inorganic ions in human nasal discharge samples using ion chromatography
PublikacjaEnvironmental tobacco smoke (ETS) is a mixture of air and tobacco smoke containing more than 4000 chemical substances. In view of the health risks of many of these substances, studies are needed to determine biomarkers of exposure to ETS constituents in people who actively or passively are exposed to the toxic compounds. The methodologies for determining most biomarkers from saliva, urine and blood samples are known, but methods...
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Separation of nitroaromatics and their transformation products in soil around ammunition plants: New high performance liquid chromatographic charge transfer stationary phases
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Antibiotic Resistance Carriage Causes a Lower Survivability Due to Stress Associated with High-Pressure Treatment among Strains from Starter Cultures
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Gaseous products from scrap tires pyrolisis
PublikacjaIn European Union 75% of used tires should be recycled. The most common method of used tires disposal, is burning in cement kilns, which does not solve the problem. Pyrolysis process can be an alternative way of utilization of tires. The aim of the researches was to check the influence of pyrolysis products (gas and oil fractions) on environment. Samples from pyrolysis process, like light oil fractions or pyrolysis gases were analyzed...
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An odor-sensing system - powerful technique for foodstuff studies
PublikacjaThis work examines gas sensor array technology combined with multivariate data processing methods and demonstrates a promising potential for rapid, non-destructive analysis of food. Main attention is focused on detailed description of sensor used in e-nose instruments, construction, and principle of operation of these systems. Moreover, this paper briefly reviews the progress in the field of artificial olfaction and future trends...
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Determination of Pesticide Residues in Honey using the GC×GC-TOFMS Technique
PublikacjaIn this study, a QuEChERS method and gas chromatography coupled with time-of-flight mass spectrometry (GCxGC-TOFMS) was developed for rapid extraction and simultaneous determination of 12 pesticide residues in honey. The GCxGC-TOFMS method was validated according to the SANCO guidance in terms of linearity, selectivity, reproducibility and recovery. Regarding the results, recovery rates ranged between 70-120% with relative standard...
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Alternative methods for dark fermentation course analysis
PublikacjaDark fermentation course analysis is crucial, as complexed matrix of gaseous components may be formed and revealed during the process. The paper considers key issues related to the microbiological process in which complex organic substances are transformed into hydrogen. For the purposes of hydrogen generation, the application of wastewater mixed sludge pre-treated according to Faloye method (Faloye et al. in Int J Hydrog Energy...
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Determination of the substances potentially allergenic in water
PublikacjaPersonal care chemicals are continuously released into environment through domestic and industrial wastewater, causing adverse effects on human health. Their presence can be detected in different environmental compartments. A group of chemicals included in most personal care products are the allergen fragrances. In the present work, simple and rapid methodology based on ultrasound-assisted emulsification-microextraction (USAEME)...
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High pressure and time resolved studies of optical properties of n-type doped GaN/AlN multi-quantum wells: Experimental and theoretical analysis
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Evaluation of the Construction and Investment Process of a High-Pressure Gas Pipeline with Use of the Trenchless Method and Open Excavation Method. Analytic Hierarchy Process (AHP)
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Impact of High Pressure on Metallophilic Interactions and Its Consequences for Spectroscopic Properties of a Model Tetranuclear Silver(I)–Copper(I) Complex in the Solid State
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The comparison of vodka, whisky and moonshine by using the electronic nose based on the technology of ultra-fast gas chromatography
PublikacjaVodka andwhisky are produced fromgrain distillates. Formerly these alcohols were very often counterfeited, by the made in home conditions spirit drink called moonshine, which is obtained by distilling a mash from the alcoholic fermentation. This study presents research aimed at checking the usefulness of the electronic nose using ultra-fast gas chromatography for the differentiation of whisky, vodka and moonshine. 12 samples of...
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The comparison of vodka, whisky and moonshine by using the electronic nose based on the technology of ultra-fast gas chromatography
PublikacjaVodka andwhisky are produced fromgrain distillates. Formerly these alcohols were very often counterfeited, by the made in home conditions spirit drink called moonshine, which is obtained by distilling a mash from the alcoholic fermentation. This study presents research aimed at checking the usefulness of the electronic nose using ultra-fast gas chromatography for the differentiation of whisky, vodka and moonshine. 12 samples of...
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Green thermoplastic poly(ether-urethane)s – synthesis, chemical structure and selected properties investigation
PublikacjaThis work aimed to characterize the effect of the monomers chemical structure on the selected properties of the green thermoplastic poly(ether-urethane)s. During synthesis two types of polyether biopolyols, 4,4′-diphenylmethane diisocyanate and bio-based 1,3-propanediol were employed. Materials were synthesized with the use of two step method and two different prepolymers, which were mixed together in equimolar quantities. Obtained...
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Validated GC–MS method for determination of bisphenol a and its five analogues in dietary and nutritional supplements
PublikacjaBisphenol A (BPA) and its analogues showing structural and functional similarity to BPA are commonly applied in various industrial applications and thus are becoming ubiquitous in the environment. At the same time there is increasing scientific evidence that exposure to these chemicals may lead to adverse health effects in human and wildlife. In recent years dietary and nutritional supplements dedicated for athletes have become...
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Methods of assaying volatile oxygenated organic compounds in effluent samples by gas chromatography—A review
PublikacjaThe paper is a review of the procedures for the determination of volatile and semivolatile oxygenated organic compounds (O-VOCs) in effluent samples by gas chromatography. Current trends and outlook for individual steps of the procedure for the determination of O-VOCs in effluents are discussed. The available sample preparation techniques and their limitations are described along with GC capillary columns used for O-VOCs separation...
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Improvement of the Water Resistance of a Narrow-Band Red-Emitting SrLiAl3N4:Eu2+Phosphor Synthesized under High Isostatic Pressure through Coating with an Organosilica Layer
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Poultry meat freshness evaluation using electronic nose technology and ultra-fast gas chromatography
PublikacjaTo ensure that chicken meat products are safe to consume, it is important to be able to reliably determine its shelf-life. To assess the applicability of ultra-fast gas chromatography and electronic nose technology in evaluation of poultry, an analysis of the headspace of ground chicken meat samples refrigerated over a period of 7 days was performed. Chemometric techniques were used to mine additional information from a multiparametric...
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Synergistic Effects of Bitumen Plasticization and Microwave Treatment on Short-Term Devulcanization of Ground Tire Rubber
PublikacjaGround tire rubber (GTR) was mechano-chemically modified with road bitumen 160/220 and subsequently treated using a microwave radiation. The combined impact of bitumen 160/220 content and microwave treatment on short-term devulcanization of GTR was studied by thermal camera, wavelength dispersive X-ray fluorescence spectrometry (WD-XRF), static headspace, and gas chromatography-mass spectrometry (SHS-GC-MS), thermogravimetric analysis...
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The difficulties in polybrominated diphenyl ethers identification by GC-EI-MS technique
PublikacjaAwareness about the harmful effects of brominated flame retardants on living organisms increases mainly due to link their presence in the human environment with health disorders. Therefore is a need to conduct research aimed at content control of these chemicals in the environment. Recent improvements in injection techniques and mass spectrometer ionization methods have led to a variety of options to determine PBDEs in environmental...
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A new cold-active β-galactosidase from Arthrobacter sp. S3* - gene cloning, overexpression, purification and properties
PublikacjaA psychrotrophic bacterium producing a cold-active β-galactosidase was isolated from Spitsbergen soil and classified as Arthrobacter sp. S3*. The gene encoding β-galactosidase was isolated from the genomic DNA library, sequenced, cloned, expressed in Escherichia coli, purified by ion exchange chromatography and characterized. The Arthrobaster sp. S3* β-galactosidase is a homotrimeric enzyme composed of 74,4 kDa subunits. It is...
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Monitoring of n-butanol vapors biofiltration process using an electronic nose combined with calibration models
PublikacjaMalodours, by definition, are generally unpleasant, nuisance smells that are a mixture of volatile chemical compounds which can be perceptible even at low concentrations. Due to the more frequent occurrence of odour nuisance associated with the odour sensations, and thus the need to remove them from the air, deodorization techniques are commonly used. Biofiltration is one of the methods of reducing odorants in the air stream. In...
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Preliminary Investigation on Auto-Thermal Extrusion of Ground Tire Rubber
PublikacjaGround tire rubber (GTR) was processed using an auto-thermal extrusion as a prerequisite to green reclaiming of waste rubbers. The reclaimed GTR underwent a series of tests: thermogravimetric analysis combined with Fourier-transform infrared spectroscopy (TGA-FTIR), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and static headspace and gas chromatography-mass spectrometry (SHS-GC-MS) in order...
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Quality of limes juices based on the aroma and antioxidant properties
PublikacjaKaffir (Citrus hystrix) and Key (Citrus aurantifolia) limes juices were investigated and compared. Two dimensional gas chromatography coupled with time-of-flight mass spectrometry (GC×GC-TOF-MS) was applied to assess the botanical origin of Kaffir and Key limes juices, based on volatile substances. The biggest differences in the contents of selected terpenes in Kaffir and Key limes occur in chemical compounds such as Limonene,...
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Dynamic Behavior of Aluminum Alloy Aw 5005 Undergoing Interfacial Friction and Specimen Configuration in Split Hopkinson Pressure Bar System at High Strain Rates and Temperatures
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High pressure processing, acidic and osmotic stress increased resistance to aminoglycosides and tetracyclines and the frequency of gene transfer among strains from commercial starter and protective cultures
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Determination of Terpene Profile in Cape gooseberry (Physalis peruviana L.) with Use of HS-SPME/GCxGC-TOFMS Method
PublikacjaFresh fruits and products made of them, especially fruit juice, provide the basic energetic substances (simple and complex sugars) and are a source of health beneficial vitamins, macro and microelements, antioxidants and compounds which are classified together with essential oils (for example terpenes), which positively affect human s health. The terpenes profile of cape gooseberry was determined by headspace solid--phase microextraction...
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Modern trends in solid phase extraction: New sorbent media
PublikacjaBased on the recently published literature, this review provides an update of the most important features and application of formats and devices employed in solid phase extraction (SPE). Special attention was paid on new trapping media proposed in SPE prior the chromatography analysis, based on the use of nanostructured materials, including carbon nanomaterials, electrospun nanofibers, dendrimes and magnetic nanoparticles, molecular...
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Determination of pharmaceuticals in fish: method optimization and occurrence in different species from Mediterranean rivers
PublikacjaThe multi-residue analytical method developed, based on accelerated solvent extraction, gel permeation chromatography purification and UPLC-MS/MS analysis allowed the simultaneous determination of 21 pharmaceuticals. Recoveries obtained for most of the target compounds were higher than 50%. The application of UPLC-MS/MS operating in the MRM mode, with two transitions monitored for each compound, provided good sensitivity and selectivity....
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Distillation cleanup preceded gc determination of short-chain monocarboxylic acids in aqueous and solid samples of wastewater origin = Oznaczanie krótkołańcuchowych kwasów monokarboksylowych w próbkach wodnych i stałych pochodzących z oczyszczalni ścieków z wykorzystaniem chromatografii gazowej poprzedzonej destylacją
PublikacjaShort-chain monocarboxylic acids (SCMAs) (C2-C5) formed in the process of aerobic biodegradation of larger organic molecules should often be monitored to optimize wastewater biological treatment and study the processes of converting organic waste matter into methane, etc. Gas chromatography (GC) seems a method of choice for such a task. Majority of samples require clean up before they can be injected into GC system. In this work...
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Determination of terpene profiles in potential superfruits
PublikacjaThe aim of this work was to characterize and compare the profiles of volatile terpenes in four potential superfruits. These profiles were determined using headspace solid-phase microextraction coupled with comprehensive two-dimensional gas chromatography linked to time-of-flight mass spectrometry. The proposed technique allowed the separation and identification of 79 terpenes present in cape gooseberry, crabapple, cherry silver...
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Determination of Biogenic Amines in Wine Using Micellar Electrokinetic Chromatography
PublikacjaProduction on a large-scale of fermented alcoholic drinks made from different kinds of fruits is carried out in homes. Although wine laws regulating home production exist, they do not include upper concentration limits of biogenic amines. Therefore, a quick and inexpensive way to determine BAs in wine is crucial. A new analytical method based on micellar electrokinetic chromatography has been developed for the separation of the...
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Application of gas chromatography to evaluate the quality of rapeseed oil
PublikacjaTwo-dimensional gas chromatography is an analytical technique, which is increasingly being used in food research. Through the analysis of volatile fraction, it is possible to determine the quality of food products. One of the reasons for the deterioration of food is thermal degradation. Products that are often subject to degradation reactions due to temperatures are edible oils. In the thesis, the results of edible oils with different...
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A headspace solid-phase microextraction method development and itsapplication in the determination of volatiles in honeys by gas chromatography
PublikacjaThe first part of the paper presents the detailed optimisation of all steps of the determination procedureof volatiles from Polish honeys by headspace solid-phase microextraction (HS-SPME) as the sample preparationmethod and gas chromatography/mass spectrometry (GC-MS) as the method of final determination.The methodology of semi-quantative analysis allowed the isolation and identification of volatile fractioncompounds from popular...
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Development of an Analytical Protocol for Determination of Cyanide in Human Biological Samples Based on Application of Ion Chromatography with Pulsed Amperometric Detection
PublikacjaA simple and accurate ion chromatography (IC) method with pulsed amperometric detection (PAD) was proposed for the determination of cyanide ion in urine, sweat, and saliva samples. The sample pretreatment relies on alkaline digestion and application of Dionex OnGuard II H cartridge. Under the optimized conditions, the method showed good linearity in the range of 1–100 μg/L for urine, 5–100 μg/L for saliva, and 3–100 μg/L for sweat...
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Construction of glucosamine-6-phosphate synthase with an internal hexahistydyl fragment
PublikacjaL-Glutamine: D-fructose-6-phosphate aminotransferase (EC 2.6.1.16), known also as glucosamine-6-phosphate (GlcN-6-P) syntase, catalyzes the first committed step in the amino sugar biosynthetic pathway in prokaryotic and eukaryotic organisms. The enzyme carries out a complex reaction involving ammonia transfer and sugar phosphate isomerization. GlcN-6-P syntase is an important point of metabolic control of amino sugar biosynthesis...
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Validation of atmospheric aerosols sampling in equivalent fractions
PublikacjaPhysical properties and chemical composition of atmospheric aerosols are of extreme importance, in many fields of interest, namely the Environment even with legal implications. Atmospheric sampling poses inherent problems with consequent demands on sampling optimisation, with sampling strategies requiring validation. In this work a study was conducted aiming at validating the collection of atmospheric aerosols in equivalent fractions....
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Properties of recombinant trehalose synthase from Deinococcus radiodurans expressed in Escherichia coli
PublikacjaA trehalose synthase gene from Deinococcus radiodurans(DSMZ 20539)containing 1659 bp reading frame encoding 552 amino acids was amplified using PCR. The gene was finally ligated into pET30Ek/LIC vector and expressed after isopropyl β-d-thiogalactopyranoside induction in Escherichia coli (DE3) Rosetta pLysS. The recombinanttrehalose synthase (DraTreS) containing a His6-tag at the C-terminus was purified by metal affinity chromatography...
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Role of distillation in determination of SCFAs in samples of different origin
PublikacjaShort-chain fatty acids (SCFAs) are very volatile compounds and choosing an appropriate isolation and enrichement technique is a key to their determination. Distillation is one of methods which can be applied. There are many types of distillation. The simplest ones are direct, steam and fractional distillation, but they are not used very often and have some drawbacks. However, many modifications of basic distillation have been...
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Thermal degradation assessment of canola and olive oil using ultra-fast gas chromatography coupled with chemometrics
PublikacjaOil blending is often used to enhance the properties of vegetable oils. The admixture of a more thermally stable oil makes the resulting blend more suitable for use in frying. A new method of quality assessment of vegetable oils used in frying is presented in this paper. In this method, ultra-fast gas chromatography coupled with flame ionization detector and chemometrics is employed. Principal component analysis was used for data...
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Detection of apple in orange juice using ultra-fast gas chromatography
PublikacjaThe determination of authenticity is an increasingly important issue for food quality and safety. The use of an electronic nose based on ultra-fast gas chromatography technique ensures rapid analysis of the volatile compounds from food products. Due to the fact that this technique enables chemical profiling of agricultural products, it can be an effective tool for authentication when combined with chemometrics. In this article...
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Elimination of excretion of ibuprofen and its metabolites in horses
PublikacjaAnalytical procedure based on application of gas chromatography-mass spectrometry (GC-MS) at the step of detection, identification and quantitation of ibuprofen (IBU) and detection of its metabolites – 1-hydroxyibuprofen (1-OH IBU) and carboxyibuprofen (CBX IBU) in horse urine by selected ion monitoring mode after sample preparation covering extraction at pH 3-4 and methylation has been used. The ions at m/z 161, 220 (methylated...
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Emission Profiles of Volatiles during 3D Printing with ABS, ASA, Nylon, and PETG Polymer Filaments
PublikacjaIn this short communication we characterize the emission of volatile organic compounds (VOCs) from fused filament fabrication (FFF) 3D printing using four polymer materials, namely polyethylene terephthalate glycol-modified (PETG), acrylonitrile styrene acrylate (ASA), Nylon, and acrylonitrile butadiene styrene (ABS). Detailed emission profiles are obtained during thermal degradation of the polymers as a function of temperature...