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Search results for: CHIRAL CHROMATOGRAPHY
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An evaluation of sucrose as a possible contaminant in e-liquids for electronic cigarettes by hydrophilic interaction liquid chromatography–tandem mass spectrometry
PublicationThe influence of sucrose combustion products on smoking and nicotine addiction is still controversial because the presence of the sucrose may be treated as a source of aldehydes and organic acids. In e-liquids used as refills for electronic cigarettes, which are made primarily of poly(propylene glycol), glycerine and ethanol, sucrose may be present at trace levels, and its impact on mainstream smoke formation, and hence on human...
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Determination of Pesticide Residues in Honeybees using Modified QUEChERS Sample Work-Up and Liquid Chromatography-Tandem Mass Spectrometry
PublicationIncreasing emissions of chemical compounds to the environment, especially of pesticides, is one of factors that may explain present honeybee colony losses. In this work, an analytical method employing liquid chromatography-tandem mass spectrometry (LC-MS/MS) was optimized for the simultaneous screening of 19 pesticides which have not been yet determined in honeybee samples from northern Poland (Pomerania). The sample preparation,...
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An evaluation of sucrose as a possible contaminant in e-liquids for electronic cigarettes by hydrophilic interaction liquid chromatography–tandem mass spectrometry
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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
PublicationA 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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In-Syringe Dispersive Liquid-Liquid Microextraction Coupled with High- Performance Liquid Chromatography for Trace Analysis of Naphthalene Sulfonates in Seawater
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Determination of volatile aliphatic amines in air by solid phase microex traction coupled with gas chromatography with flame ionization detection.
PublicationOpisano nową metodę oznaczania lotnych amin alifatycznych w powietrzu. Metodyka oparta jest na zastosowaniu techniki mikroekstrakcji do fazy stacjonarnej na etapie pobierania próbek oraz zestawu GC-FID do rozdzielania i oznaczania poszczególnych analitów.Badaniom poddano nowe typy faz stacjonarnych.Zbadano wpływ wilgotności powietrza na proces pobierania próbek analitów z powietrza.
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Partition coefficients of selected environmentally important volatile organic compounds determined by gas - liquid chromatography with polydimethylsiloxane stationary phase
PublicationPrzedstawiono wartości współczynników podziału (stałych podziału) 14 lotnych związków organicznych istotnych dla stanu środowiska (często oznaczanych w powietrzu w pomieszczeniach zamkniętych) między fazą gazową (N2) a ciekłą (PDMS). Wyznaczano je dwiema technikami (izotermiczną i z liniowo programowanym wzrostem temperatury). Dowiedziono, że istnieje możliwość wyznaczania współczynników podziału techniką LTPRI w oparciu o skalę...
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Determination of nonsteroidal antiinflammatory drugs in water samples using liquid chromatography coupled with diode-array detector and mass spectrometry
PublicationOpracowano i zwalidowano metodykę do oznaczania śladowych ilości sześciu różnych związków z grupy niesteroidowych leków przeciwzapalnych w próbkach wodnych. Anality zostały wybrane spośród najczęsciej sprzedawanych leków w Polsce. Sprawdzono kilka różnych kolumienek ekstrakcyjnych i wybrano RP-18 jako najlepsze wypełnienie do wzbogacania oznaczanych związków. Opracowaną metodykę z powodzeniem zastosowano do analizy próbek rzeczywistych.
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The quantification of bisphenols and their analogues in wastewaters and surface water by an improved solid-phase extraction gas chromatography/mass spectrometry method
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Direct injection liquid chromatography-mass spectrometry (DI-LC-MS) analysis for rapid lipidomic profiling of extracellular vesicles
PublicationExtracellular vesicles (EVs) are small, spherical particles produced by eukaryotic and prokaryotic cells, surrounded by a bilayer membrane and carrying various bioactive molecules, such as proteins, surface receptors, membrane and soluble proteins, lipids, and nucleic acids. EVs are of substantial interest because of their important roles in cell communication, epigenetic regulation and possible application in disease diagnosis...
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Determination of Nine Intense Sweeteners in Foodstuffs by High-Performance Liquid Chromatography and Evaporative Light-Scattering Detection: Interlaboratory Study
PublicationW pracy przedstawiono wyniki badań międzylaboratoryjnych, opracowanej wcześniej metody jednoczesnego oznaczania dziewięciu słodzików o wysokiej mocy w produktach żywnościowych. W badaniach wzięło udział siedem laboratoriów (Belgia, Niemcy, Portugalia). W rezultacie dowiedziono, iż opracowana metoda umożliwia uzyskanie dokładnych, powtarzalnych i odtwarzalnych wyników analiz dla wszystkich badanych słodzików i typów żywności.
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Quantitative structure—retention relationship modeling of the retention behavior of selected antipsychotic drugs in normal-phase thin-layer chromatography
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Membrane extraction with sorbent interface-gas chromatography as an effective and fast means for continuous monitoring of thermal degradation products of polyacrylonitrile
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A Fast and Validated Method for the Determination of Malondialdehyde in Fish Liver Using High-Performance Liquid Chromatography with a Photodiode Array Detector
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Development and Validation of a Gas Chromatography Method for the Trace Level Determination of Allylamine in Sevelamer Hydrochloride and Sevelamer Carbonate Drug Substances
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Analysis of pesticide residues in fruits and vegetables using QuEChERS sample preparation method and gas chromatography with electron capture detection
PublicationPesticides are a numerous and diverse group of chemical compounds. They are some of the most toxic substances contaminating the environment, which are used to eliminate pests in agriculture and the household. Despite considerable progress in the development of methods for preparing samples for analysis and for the final determination of analytes, the analysis of pesticides in biological samples continues to present challenges to...
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Monolithic capsule phase microextraction prior to gas chromatography-mass spectrometry for the determination of organochlorine pesticides in environmental water samples
PublicationIn this study, a capsule phase microextraction (CPME) protocol followed by gas chromatography-mass spectrometry is proposed for the accurate and sensitive monitoring of organochlorine pesticides (OCPs) in environmental water samples. Different monolithic sol–gel encapsulated sorbents were compared and monolithic sol–gel poly(ethylene glycol)-based sorbent incorporated into porous microextraction capsules resulted in the highest...
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Determination of fuel combustion product in airport runoff water samples using liquid–liquid extraction with gas chromatography–spectrometry
PublicationDetermination of xenobiotics in samples of airport runoff water is both a complex and indispensable task due to an increasing threat resulting from the activities of numerous airports. The aim of this study was to develop, optimize, and validate a procedure based on liquid–liquid extraction (LLE) coupled with gas chromatography–mass spectrometry (GC–MS) for the determination of polycyclic aromatic hydrocarbons (PAHs). So far, no...
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Evaluation of Gas Chromatography Stationary Phases Based on Morpholinium Ionic Liquids by McReynolds Constants and Activity Coefficients at Infinite Dilution
PublicationIn this work, four ionic liquids (ILs) based on the N-alkyl-N-methylmorpholinium cation ([Mor1,R], in which R = 2, 4, 8, or 10) and bis (trifluoromethanesulfonyl)imide anion were synthesized. Using GLC, a number of parameters describing the sorption properties of the investigated ILs were determined. The values of Kovats indices, McReynolds constants, and activity coefficients at infinite dilution were the basis for the evaluation...
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Rapid determination of multiple aminoglycoside antibiotics in veterinary formulations by ion-pair chromatography coupled with evaporative light scattering detection
PublicationA fast and simple method for simultaneous determination of eight aminoglycoside antibiotics using ion-pairing liquid chromatography (IPLC) coupled with evaporative light scattering detection (ELSD) has been developed and validated. Separation of amikacin, apramycin, gentamicin (as a sum of gentamicin C1, C2 and C1A), kanamycin A, neomycin B, paromomycin, streptomycin and tobramycin was achieved using C18 column with H2O and MeOH/acetone,...
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Chiralne i achiralne struktury supramolekularne z udziałem oksamidów i ich pochodnych tiokarbonylowych
PublicationCelem pracy była synteza serii oksamidów oraz ich analogów tio- i ditiokarbonylowych, a następnie zbadanie zdolności tych związków do samoorganizacji w kryształach oraz kokryształach z innymi substancjami. Istotnym elementem tych badań było ustalenie wpływu chiralności cząsteczek na sposób ich upakowania w sieci krystalicznej. Ponadto długofalowa absorpcja tiopochodnych umożliwiła przeprowadzenie studiów spektroskopowych otrzymanych...
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The chromatographic analysis of extracts from poplar (Populus sp.) - Laying program GC-MS
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How Much Can We Learn from a Single Chromatographic Experiment? A Bayesian Perspective
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Development of chromatographic and mass spectrometry conditions for untargeted lipidomic analysis of human breast milk
PublicationHuman breast milk (HBM) is a complex biofluid containing components which are essential for the proper growth of the newborn (for example nutrients such as carbohydrates, proteins, lipids) and also bioactive substances. According to the literature, most of studies involving HBM nutrients investigations focused essentially on the determination of proteins. The molecular composition of lipids in HBM is not well known as the protein...
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Mesophilic and thermophilic dark fermentation course analysis using sensor matrices and chromatographic techniques
PublicationProduction of biofuels from biomass is expected to benefit the society and the environment. At present, bio waste residues processing includes hydrolysis, dark fermentation, photofermentation, pyrolysis, gasification, and chemical synthesis. As the composition and the chemical structure of organic substances affect the efficiency of mentioned processes, it is believed that the glucose concentration is a crucial parameter for the...
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Milky Sap of Greater Celandine (Chelidonium majus L.) and Anti-Viral Properties
PublicationThe milky juice of the greater celandine herb has been used in folk medicine and in homeopathy for treatment of viral warts for years. However, classical medicine fails to use properties of celandine herbs in treatment of diseases induced by papilloma viruses. Nevertheless, dermatological outpatient clinics are regularly visited by patients reporting efficacy of milky sap isolated from celandine herb in treatment of their own...
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Free Energies of the Disassembly of Viral Capsids from a Multiscale Molecular Simulation Approach
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The Mechanisms of Changes in the Infrastructure of the Payment Card Market—A Comparative Analysis of Poland and China
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Evolutionary Game Analysis of the Partners’ Behavior in the Rural E-Payment Market of China
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Global value chains, wages, employment and labour production in China: A regional approach
PublicationIn this study we analyse the relationship of trade and global value chains (GVCs) to the labour market in 31 Chinese provinces for 25 sectors, by means of a system of structural equations. We firstly distinguish between provincial value chains (PVCs) and interprovincial value chains (PRVCs) in order to outline their distribution and evolution over time. Then, we investigate to what extent participation in GVCs, PVCs and PRVCs –...
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Investment strategy of sovereign wealth funds from emerging markets: the case of China
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Determination of trace levels of eleven bisphenol A analogues in human blood serum by high performance liquid chromatography–tandem mass spectrometry
PublicationChemicals showing structural or functional similarity to bisphenol A (BPA), commonly called BPA analogues, have recently drawn scientific attention due to their common industrial and commercial application as a substitute for BPA. In the European Union, the use of BPA has been severely restricted by law due to its endocrine disrupting properties. Unfortunately, it seems that all BPA analogues show comparable biological activity,...
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A rapid and sensitive method for the quantitative analysis of ibuprofen and its metabolites in equine urine samples by gas chromatography-tandem mass spectrometry
PublicationIbuprofen is widely used in human and veterinary medicine for the treatment of chronic pain as well as rheumatic and musculoskeletal disorders. However, t he anal- gesic and anti-inflammatory properties of Ibuprofen have contributed to frequent drug abuse in equestr ian s ports. A sensitive and rapid gas chromatography with tandem mass spectrometry based method with a simple liquid-liquid extraction and deriva- tization requiring...
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Fingerprint comparison of low-volatile petroleum products by means of Thin Layer Chromatography (TLC) for identification of process leakages and environmental pollution
PublicationW pracy zbadano możliwość zastosowania stosunkowo prostej i szybkiej procedury przygotowania próbki, rozdzielania grup składników techniką cienkowarstwowej chromatografii cieczowej (TLC), wizualizacji w świetle UV 254 oraz 360 nm i analizy porównawczej cech plamek na płytkach TLC do określenia rodzaju niskolotnego materiału ropopochodnego stanowiącego zanieczyszczenie wód procesowych, lub wyciek z instalacji w rafinerii ropy naftowej....
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Capillary gas chromatography using a -cyclodextrin forenantiomeric separation of methylamphetamine, its precursors andchloro intermediates after optimization of the derivatization reaction
PublicationtThe enantiomeric ratio of methylamphetamine (MAMP) is closely related to the optical activity of precur-sors and reagents used for the synthesis and this knowledge can provide useful information concerningthe origins and synthetic methods used for illicit manufacture. The information can be utilized for reg-ulation of the precursors and investigation of the manufacturing sources but this requires analyticalprocedures to determine...
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Complementary Use of Multi-dimensional Gas Chromatography and Proton Transfer Reaction Mass Spectrometry for Identification of Rapeseed Oil Quality Indicators
PublicationThe change of concentration of various volatiles generated during frying may be an indicator of oil quality. Chemical compounds such as aldehydes, ketones, alcohols and carboxyl acids are the products of oxidation during thermal degradation of edible oils. Shown in this work is a complementary use of GC×GC-TOFMS and PTR-MS for the detection and determination of quality indicators of rapeseed oil. The former technique was used for...
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Rapid Characterization of the Human Breast Milk Lipidome Using a Solid-Phase Microextraction and Liquid Chromatography-Mass Spectrometry-Based Approach.
PublicationHuman breast milk (HBM) is a biofluid consisting of various biomolecules such as proteins, lipids, carbohydrates, minerals and bioactive substances. Due to its unique and complex composition, HBM provides not only nutritional components required for the growth of the infant, but also additional protection against infections. Global insight into the composition of HBM is crucial to understanding the health benefits infants receive...
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Thermal decomposition of surface compounds for the generation of small quantities of acetaldehyde. Calibration of a thermal desorption gas chromatography flame ionization detection.
PublicationW pracy opisano sposób wytwarzania niewielkich ilości acetaldehydu w procesie termicznego rozkładu związku powierzchniowego uzyskanego w wyniku chemicznej modyfikacji żelu krzemionkowego.Proces rozkładu prowadzony jest w temperaturze 130-190 stopni Celsjusza.Przedstawiono również sposób syntezy prowadzący do uzyskania odpowiedniego związku powierzchniowego.
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Application of gas chromatography to the study of the kinetics of reactionsin solution. Ring opening reactions for á-lactams studied using internal standard
PublicationW pracy przedstawiono metodę badania kinetyki reakcji otwarcia pierścienia á-laktamu, wykorzystującą technikę chromatografii gazowej. Na podstawie badań kinetyki reakcji w różnych temperaturach wyznaczono wartości energii aktywacji dwóch badanych reakcji. Podstawowym celem pracy było pokazanie możliwości wykorzystania GC w badaniach kinetyki reakcji prowadzonych w mikroskali.
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Determination of robenidine in animal feeds by liquid chromatography coupled with diode-array detection and mass spectrometry after accelerated solvent extraction
PublicationRobenidyna (chlorowodorek 1,3-bis[(4-chlorobenzylideno)amino]guanidyny) jest stosowana w celu zapobiegania i leczenia kokcydiozy - pasożytniczej choroby układu pokarmowego wielu zwierząt hodowlanych (kozy, owce, króliki, drób) wywoływanej przez pierwotniaki należące do rzędu Eimeria tenella, E. Necatrix, E. Acervulina, E. Maxima, E. Brunetti, and E. Mivati. Robenidyna wykazuje stosunkowo wysoką skuteczność terapeutyczną, przy niewielkiej...
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Separation of Monovinyl and Divinyl Protochlorophyllides Using C30 Reverse Phase High Performance Liquid Chromatography Column: Analytical and Preparative Applications
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Quantification of DNA Modifications Using Two-Dimensional Ultraperformance Liquid Chromatography Tandem Mass Spectrometry (2D-UPLC-MS/MS)
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Analysis of serum homocysteine in the laboratory practice - comparison of the direct chemiluminescence immunoassay and high performance liquid chromatography coupled with fluorescent detection
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THE USE OF ULTRAFAST GAS CHROMATOGRAPHY FOR CLASSIFICATION OF PLUM SPIRITS = SPOSÓB WYKORZYSTANIA ULTRASZYBKIEJ CHROMATOGRAFII GAZOWEJ DO KLASYFIKACJI OKOWIT ŚLIWKOWYCH
PublicationStan środowiska ma znaczny wpływ na jakość upraw. W konsekwencji występowanie zanieczyszczeń w powietrzu ma istotny wpływ na jakość żywności. W skutek złego stanu powietrza zewnętrznego i wewnętrznego zmieniają się m.in. walory sensoryczne i zdrowotne niektórych produktów spożywczych. Z tego powodu należy nieustannie monitorować stan środowiska za pomocą m.in. nowoczesnej aparatury analitycznej jakim jest elektroniczny nos. W...
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Identification and characterization of the Indian Yellow dyestuff and its degradation products in historical oil paint tube by liquid chromatography mass spectrometry
PublicationAn analytical protocol for identification of dyes using reversed phase liquid chromatography-mass spectrometry with atmospheric pressure electrospray ionization (LC-ESI/MS) is presented. The developed method has been successfully applied in identification of euxanthic acid and euxanthone, the main components of the Indian Yellow dye in a historical oil paint tube produced by Richard Ain`es, a recognizable French company supplying...
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Simultaneous Determination of Indolic Compounds in Plant Extracts by Solid-Phase Extraction and High-Performance Liquid Chromatography with UV and Fluorescence Detection
PublicationA high-performance liquid chromatographic method with UV and fluorescence detection (HPLC-DAD-FLD) was developed for simultaneous determination of indolic compounds in plant material. Indole-3-carbinol (I3C), indole-3-acetic acid (I3AA), indole-3-acetonitrile (I3ACN), and 3,3′-diindolylmethane (DIM) were used as representative compounds that cover a wide spectrum of indole structures occurring in nature. For concentration and purification...
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Sensitive simultaneous determination of 19 fluorobenzoic acids in saline waters by solid-phase extraction and liquid chromatography–tandem mass spectrometry
PublicationA solid-phase extraction (SPE) procedure using C18 stationary phase was optimized for the preconcentration of 19 fluorinated derivatives of benzoic acid (FBA): mono-, di-, tri-, and tetrafluorosubstituted in the ring, trifluoromethylbenzoic acid and 3,5-bistrifluoromethyl benzoic acid from undiluted salt-rich (>20%) reservoir waters. Quantitative (>90%) retention/elution of 16 out of 19 analyte compounds was achieved allowing a...
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The efficiency comparison of ramentaceone isolation from Drosera aliciae plants using normal and reversed phase preparative liquid chromatography technique
PublicationW pracy zaprezentowano optymalne warunki otrzymywania ramentaceonu z chloroformowego ekstraktu z rośliny D. muscipula. Opracowano i przedstawiono dwie procedury otrzymywania ramantaceonu z wykorzystaniem NP-PLC i RP-PLC. Dla produktu o określonej czystości, porównano maksymalny stopień przeładowania kolumny, efektywność procesu wyrażoną jako ilość substancji otrzymanej w jednostce czasu oraz produktywność kolumny, wyrażoną jako...
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Zastosowanie chromatografii jonowej w analityce opadów i osadów atmosferycznych = Application of ion chromatography in atmospheric precipitation and deposit analysis
PublicationNajwiększy udział w dostawie zanieczyszczeń z atmosfery do powierzchni ziemi w regionach położonych w znacznych odległościach od źródeł emisji ma depozycja mokra (opady i osady atmosferyczne). Wody opadowe i wody spływne (również powstające z osadów atmosferycznych) dostają się wraz z zawartymi w nich związkami toksycznymi do wód powierzchniowych i gruntowych, które stanowią źródło wody pitnej. Pojawiła się więc konieczność stałego...
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Development of headspace-gas chromatography-flame ionization detection procedure to determine volatile fatty acids in zoo organic waste leachate
PublicationNadrzędnym celem pracy było opracowanie metodyki oznaczania lotnych kwasów tłuszczowych z fazy nadpowierzchniowej opartej na chromatografii gazowej z detektorem płomieniowo-jonizacyjnym oraz sprawdzenie jej przydatności w analizie próbek odcieku ze składowiska odpadów ogrodu zoologicznego. Na podstawie przeprowadzonych badań określono warunki, w jakich przebiegać powinna izolacja lotnych kwasów tłuszczowych, a także określono najlepsze...