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Search results for: high performance liquid chromatography
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Na3PO4 assistant dispersion of nano-CaCO3 template to enhance electrochemical interface: N/O/P co-doped porous carbon hybrids towards high-performance flexible supercapacitors
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In-situ generation of Ag, Cd, Hg, In, Pb, Tl and Zn volatile species by flowing liquid anode atmospheric pressure glow discharge operated in gaseous jet mode – Evaluation of excitation processes and analytical performance
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Design, engineering, and performance of nanorod-Fe2O3@rGO@LaSrFe2-Co O6 (n = 0, 1) composite architectures: The role of double oxide perovskites in reaching high solar to hydrogen efficiency
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Expression of Deinococcus geothermalis Trehalose Synthase Gene in Escherichia coli and Its Enzymatic Properties
PublicationA novel trehalose synthase gene from Deinococcus geothermalis (DSMZ 11300) containing 1,692 bp reading-frame encoding 564 amino acids was amplified using PCR. The gene was ligated into pET30Ek/LIC vector and expressed after isopropyl alfa-D-thiogalactopyranoside induction in Escherichia coli BL21(DE3)pLysS. The recombinant trehalose synthase (DgeoTreS) containing a His6 tag at the C-terminus was purified by metal affinity chromatography...
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Copolymerization of Styrene and Pentadecylphenylmethacrylate (PDPMA): Synthesis, Characterization, Thermomechanical and Adhesion Properties
PublicationThe copolymerization of styrene (St) with a bioderived monomer, pentadecylphenylmethacrylate (PDPMA), via atom transfer radical polymerization (ATRP) was studied in this work.The copolymerization reactivity ratio was calculated using the composition data obtained from1HNMR spectroscopy, applying Kelen-Tudos and Finemann-Ross methods. The reactivity ratio of styrene (r1=0.93) and PDPMA (r2=0.05) suggested random copolymerization...
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Interaction of human serum albumin with volatiles and polyphenols from some berries
PublicationHeadspace solid-phase microextraction coupled with comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (HS-SPME/GC GCeTOFMS) identified 19 and quantified 6 monoterpenes in gooseberries, blueberries and cranberries. As a protein model human serum albumin (HSA) was used in interaction with terpenes. Specific binding of terpenes to HSA under the physiological conditions was a result of the formation...
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Determination of odour concentration by TD-GC×GC–TOF-MS and field olfactometry techniques
PublicationField olfactometry is one of the sensory techniques used to determine odour concentration, in atmospheric air, directly in emission sources. A two-dimensional gas chromatography with time of flight mass spectrometer (GC×GC–TOF-MS) allows performing the chemical characterization of various groups of chemical compounds, even in complex mixtures. Application of these techniques enabled determination of odour concentration level in...
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Degradation kinetics and mechanism of pentoxifylline by ultraviolet activated peroxydisulfate
PublicationDegradation of pentoxifylline (PTX) by sodium peroxydisulfate (SPDS) assisted by UV irradiation has been investigated in deionized water. The treatment was more favorable over direct photolysis or peroxydisulfate oxidation alone. The effects of various parameters, including different dosage of oxidant agent, PTX concentration, initial solution pH levels, and the presence of inorganic ions like chloride, nitrate and carbonate have...
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Chemical Composition of Atmospheric Air in Nemoral Scots Pine Forests and Submountainous Beech Forests: The Potential Region for the Introduction of Forest Therapy
PublicationStudies show that forests are one of the main recreational destinations. This can be explained by their beneficial effects on the health of their visitors, which can be attributed to compounds from the terpene group. The aim of this research was to determine the chemical composition of air in the interiors of Nemoral Scots pine forests and submountainous beech forests, with the determination of compounds of the terpene group. Samples...
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Multi-residue method for the determination of 16 recently used pesticides from various chemical groups in aqueous samples by using DI - SPME coupled with GC-MS
PublicationA simple and solvent-free multi-residue method has been optimized to determine 16 currently used pesticides from different chemical groups in aqueous samples. The extraction of analytes was carried out with direct immersion solid-phase microextraction (DI-SPME) and for the identification and quantitative determination gas chromatography coupled with mass spectrometry (GC-MS) was applied. Two commonly used adsorbent coatings have...
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Chemical composition of shells from red (Strongylocentrotus franciscanum) and green (Strongylocentrotus droeba-chiensis) sea urchin
PublicationThe shells from red and green sea urchins accounted for 47.9 and 40.7% of their body weights, respectively. The red and green sea urchin shells contained 91.08 and 90.77% minerals and 4.06 and 4.99% proteins, respectively. The shells did not contain any chitin. Sea urchin shells had a relatively large amount of naphthoquinone pigments, 121 mg per 100 g in red and 163 mg per 100 g in green species. The small quantities of glucosamine...
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Qualitative characteristics and comparison of volatile fraction of vodkas made from different botanical materials by comprehensive two-dimensional gas chromatography and the electronic nose based on the technology of ultra-fast gas chromatography
PublicationBACKGROUND Vodka is a spirit-based beverage made from ethyl alcohol of agricultural origin. At present, increasingly more vodka brands have labels that specify the botanical origin of the product. Until now, the techniques for distinguishing between vodkas of different botanical origin have been costly, time-consuming and insufficient for making a distinction between vodka produced from similar raw materials. Therefore, it is...
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International Conference on High Performance Scientific Computing
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ISC High Performance (was International Supercomputing Conference)
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International Symposium on High Performance Computer Architecture
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IEEE Workshop on High Performance Switching and Routing
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International Conference on High Performance Computing and Networking
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Technology of an adhesive silicone film as drug carrier in transdermal therapy I. Analytical methods used for characterization and design of the universal elastomer layers
PublicationSilicone polymers possess unique properties, which make them suitable for many different applications, for example in the pharmaceutical and medical industry. To create an adhesive silicone film, the appropriate silicone components have to be chosen first. From these components two layers were made: an adhesive elastomer applied on the skin, and a non-adhesive elastomer on the other side of the film. The aim of this study was...
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Matrix solid-phase dispersion (MSPD) as simple and useful sample preparation technique for determination of polybrominated diphenyl ethers (PBDEs) in dust
PublicationIn the present study a novel analytical procedure for the determination of polybrominated diphenylethers in dust samples was developed.The main aim of the research was the selection of the optimum conditions of the matrix solid-phasedispersion before thefinal determination of polybrominated diphenyl ethers in dust samples. In order toassess the best usefulness of this technique, a favourable ratio of sample amount to the mass ofdispersing...
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The influence of different glycerine purities on chemical recycling process of polyurethane waste and resulting semi‐products
PublicationChemical recycling is the most favourable recycling method due to the possibility of polyol recovery. This work is dedicatedto the utilisation of crude glycerine and polyurethane waste. It aims at determining the impact of the use of glycerine fromthe production of biodiesel with various degrees of purity as a cleavage agent on the decomposition process of polyurethanefoam. The influence of glycerine purit y on the chemical structure...
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Application of ion chromatography with pulsed amperometric detection for the determination of trace cyanide in biological samples, including breast milk
PublicationCyanide (CN) is the biomarker of exposure to the components of tobacco smoke, although its presence in biological samples is also due to the consumption of products containing cyanogenic glycosides. In this work, we determine the concentration of the free cyanide in urine, saliva and breast milk matrices, using ion chromatography with pulsed amperometric detection (IC-PAD). IC-PAD is an emerging method, with only few documented...
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Comparison of the Physical and Sensory Properties of Hybrid Citrus Fruit Jaffa® Sweetie in Relation to the Parent Fruits
PublicationIn the presented study, an overall Jaffa sweetie evaluation was made to find a correlation between Citrus grandis Osbeck × Citrus paradisi Macf. and its parent fruits’ (Citrus grandis Osbeck, Citrus paradisi Macf.) properties. Based on the sensory analysis, it was found that the taste and aroma of the new hybrid fruit are close to pummelo. By the use of chromatographic analysis, the selected monoterpenes present in the fruits were...
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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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The Verification of the Usefulness of Electronic Nose Based on Ultra-Fast Gas Chromatography and Four Different Chemometric Methods for Rapid Analysis of Spirit Beverages
PublicationSpirit beverages are a diverse group of foodstuffs. They are very often counterfeited which cause the appearance of low quality products or wrongly labelled products on the market. It is important to find a proper quality control and botanical origin method enabling the same time preliminary check of the composition of investigated samples, which was the main goal of this work. For this purpose, the usefulness of electronic nose...
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Optical properties of phenylene–thiophene-based polyazomethine thin films
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Process Control and Investigation of Oxidation Kinetics of Postoxidative Effluents Using Gas Chromatography with Pulsed Flame Photometric Detection (GC-PFPD)
PublicationThis article presents the results of investigations on the use of headspace analysis and gas chromatography with pulsed flame photometric detection (HSA-GC-PFPD) to evaluate the effectiveness of oxidation of postoxidative effluents from the production of bitumens. Samples of effluents from the bitumen oxidation unit were used in the experiments. In addition, the kinetics of effluent oxidation was also investigated. The content...
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In-tube extraction for the determination of the main volatile compounds in Physalis peruviana L
PublicationAn analytical procedure based on in-tube extraction followed by gas chromatography with mass spectrometry has been developed for the analysis of 24 main volatile components in cape gooseberry (Physalis peruviana L.) samples. According to their chemical structure, the compounds were organized into different groups: one hydrocarbon, one aldehyde, four alcohols, four esters, and 14 monoterpenes. By single-factor experiments, incubation...
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α-Pinene, 3-carene and d-limonene in indoor air of Polish apartments: The impact on air quality and human exposure
PublicationMonoterpenes are among most ubiquitous volatile organic compounds (VOCs) to be detected in indoor air. Since the quality of indoor air is considered important for inhabitants' well-being, the present study aimed at investigating impact of human activity on levels of selected monoterpenes applying passive sampling technique followed by thermal desorption and gas chromatography coupled mass spectrometry. One of the objectives of...
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Modern approach for determination of lactulose, mannitol and sucrose in human urine using HPLC-MS/MS for the studies of intestinal and upper digestive tract permeability
PublicationA new analytical procedure was described for the simultaneous determination of lactulose, mannitol and sucrose in urine, in which HILIC chromatography and tandem mass spectrometry detection are used. Sugars are orally administered for the estimation of intestinal permeability in children digestive tract. Samples were purified by dispersive solid phase extraction (d-SPE) using Amberlite MB150 resin. Raffinose was selected as an...
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Waterborne polyesters partially based on renewable resources
PublicationA new experimental approach for preparing biobased, water-soluble polyesters via titanium(IV) n-butoxide-catalyzed bulk polycondensation is presented. In the described method polymers were obtained from isosorbide, maleic anhydride and poly(ethylene glycol). The chemical structure of the synthesized polyesters was confirmed using 2D NMR spectroscopy and by titration methods. Careful analysis of 2D NMR spectra viz. Correlation Spectra...
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Highly effective asphaltene-derived adsorbents for gas phase removal of volatile organic compounds
PublicationA novel nitrated asphaltene-derived adsorbent (Asf-Nitro) was prepared using facile isolation and modification procedures. The successful modification was confirmed by Fourier-transform infrared spectroscopy (FTIR). The nitrated adsorbent was evaluated in terms of dispersive and specific interactions, Lewis acid-base properties and adsorption isotherms by means of inverse gas chromatography (IGC). Nitration was found to be extremely...
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Real-time monitoring of the emission of volatile organic compounds from polylactide 3D printing filaments
PublicationEstablishing the emission profile of volatile organic compounds generated during fused deposition modeling 3D printing using polymer filaments is important in terms of both understanding the processes taking place during thermal degradation of thermoplastics, and assessing the user's exposure to potentially harmful volatiles. However, obtaining detailed, real-time qualitative and quantitative results poses a challenge. In this...
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Composition of fatty acids in selected sorts of biscuits, offered for children
PublicationThe fatty acid (FA) composition, especially total trans-fatty acids (TFA) content in 12 assortments of biscuits offered for children, produced by four different companies, were determined by gas chromatography. Total fat content of the biscuit samples ranged from 2.2 to 22.8 g/100 g of product. The major FAs were palmitic C16:0, oleic C18:1, and linoleic C18:2 acids. Depending on the biscuit type, the total saturated fatty acids...
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Homoisocitrate dehydrogenase from Candida albicans: properties, inhibition, and targeting by an antifungal pro-drug
PublicationThe LYS12 gene from Candida albicans, coding for homoisocitrate dehydrogenase was cloned and expressed as a His-tagged protein in Escherichia coli. The purified gene product catalyzes the Mg2+- and K+-dependent oxidative decarboxylation of homoisocitrate to alpha-ketoadipate. The recombinant enzyme demonstrates strict specificity for homoisocitrate. SDS-PAGE of CaHIcDH revealed its molecular mass of 42.6±1 kDa, while in size-exclusion...
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Studies of the separation performance of silanized silica gel for simulated distillation
PublicationWe present the results of investigations of the chromatographic (sorptive) properties of silanized silica gel as a stationary phase for gas chromatography used for simulated distillation. Commercially available silanized sorbent (particle diameter range 63–200 m, average pore size 60 Å) was sieved to obtain the 80–100 mesh fraction (180–150 m). The obtained results revealed that silanized silica gel allows the complete separation...
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International Symposium on Computer Architecture and High Performance Computing
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IEEE International Conference on High Performance Computing and Simulation
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ACM International Symposium on High Performance Distributed Computing
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International Meeting on High Performance Computing for Computational Science
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IEEE International Conference on High Performance Computing and Communications
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Identification and properties of the psychrophilic bacterium Desulfolatea psychrophila single-stranded DNA binding proteins
PublicationTo study the biochemical properties of SSB from Desulfolatea psychrophila (DpsSSB), we have cloned the ssb genes obtained by PCR and have developed Escherichia coli overexpression systems. The gene consists of an open reading frame of 426 nucleotides encoding SSB protein of 142 amino acids with a calculated molecular mass of 15.6 kDa and it is the smallest known bacterial SSB protein indentified to date. The amino-acid sequence...
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Production of essential oils from in vitro cultures of Caryopteris species and comparison of their concentrations with in vivo plants
PublicationThe chemical composition of hydrodistilled essential oils obtained from aerial parts and roots of selected Caryopteris (‘bluebeard’) species (C. incana, C. mongolica, Caryopteris 9 clandonensis), as well as the newly established in vitro shoot and adventitious root cultures of the above plants, was analyzed by gas chromatography– mass spectrometry. Essential oil content and composition differed significantly depending on the type...
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Pesticides in rain and roof runoff waters from an urban region
PublicationThe levels of organonitrogen, organochlorine and organophosphorus pesticides were monitored in rain and roof runoff waters in Gdask (Poland) over a period of 6 months (October 2000 - March 2001). Buildings included in the study were of different ages, and covered with a variety of roofing materials. Samples were collected during the precipitation events. Pesticides were determined by gas chromatography combined with NPD and ECD...
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Ground Tire Rubber Modified by Elastomers via Low-Temperature Extrusion Process: Physico-Mechanical Properties and Volatile Organic Emission Assessment
PublicationIn this paper, low-temperature extrusion of ground tire rubber was performed as a proecological waste tires recycling method. During this process, ground tire rubber was modified with constant content of dicumyl peroxide and a variable amount of elastomer (in the range: 2.5–15 phr). During the studies, three types of elastomers were used: styrene-butadiene rubber, styreneethylene/butylene-styrene grafted with maleic anhydride and...
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Direct solid phase microextraction combined with gas chromatography – Mass spectrometry for the determination of biogenic amines in wine
PublicationA direct method based on immersion solid phase microextraction (DI-SPME) gas chromatography mass-spectrometry (GC-MS) was optimized and validated for the determination of 16 biogenic amines in Polish wines. In the analysis two internal standards were used: 1,7-diaminoheptane and bis-3-aminopropylamine. The method allows for simultaneous extraction and derivatization, providing a simple and fast mode of extraction and enrichment....
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Interrelationship between total volatile organic compounds emissions, structure and properties of natural rubber/polycaprolactone bio-blends cross-linked with peroxides
PublicationNatural rubber/polycaprolactone (NR/PCL) bio-based blends with different organic peroxides were prepared using an internal batch mixer and subsequently cross-linked at 170°C. Two types of commonly used organic peroxides, dicumyl peroxide and di(tert-butylperoxyisopropyl)benzene peroxide, were applied as free-radical initiator. Cross-linking efficiency of NR/PCL blends were investigated using oscillating disc rheometer measurements,...
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Key-Marker Volatile Compounds in Aromatic Rice (Oryza sativa) Grains: An HS-SPME Extraction Method Combined with GC×GC-TOFMS
PublicationThe aroma of rice essentially contributes to the quality of rice grains. For some varieties, their aroma properties really drive consumer preferences. In this paper, using a dynamic headspace solid-phase microextraction (HS-SPME) system coupled to a two-dimensional gas chromatography (GC×GC) using a time-of-flight mass spectrometric detector (TOFMS) and multivariate analysis, the volatile compounds of aromatic and non-aromatic...
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Polychlorinated biphenyls (PCBs) and polychlorodibenzo-p-dioxins (PCDDs) determination in disposable baby diapers with the application of natural deep eutectic solvent
PublicationIn this work a new method involving solvent extraction of porous membrane-packed solid samples (SE-PMSS) coupled to gas chromatography-mass spectrometry (GC–MS) has been developed for the determination of six polychlorinated biphenyls (PCBs) and five polychlorodibenzo-p-dioxines (PCDDs) in disposable baby diapers. In that aim, a terpenoid-based natural deep eutectic solvent (NADES) composed of carvone and camphor in a 1:1 M ratio...
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Thermo-oxidative exfoliation of carbon black from ground tire rubber as potential reinforcement in green tires
PublicationConsidering the balance between rapidly growing global tire demand and scarcity of natural resources, recycling and reclaiming techniques of tire rubber have become the state of the art. Herein, we set out to implement a self-designed thermo-oxidative reactor for the exfoliation of carbon black (CB) from ground tire rubber, which is efficiently functioned under a thermo-oxidative reclaiming condition without any additive. The exfoliation...
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Microbial and chemical quality assessment of the small rivers entering the South Baltic. Part II: Case study on the watercourses in the Puck Bay catchment area
PublicationDue to its location, Puck Bay is an area particularly vulnerable to pollution of anthropogenic origin. The aim of the study was to assess the water quality of small watercourses entering the inner part of Puck Bay. The paper presents the results of chemical and microbiological analyses of 10 rivers and canals at their estuaries located on the western shore of the internal Puck Bay. The following environmental parameters were analyzed:...