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Wyniki wyszukiwania dla: VOLATILE FATTY ACIDS
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Accumulation of volatile constituents in agar and bioreactor shoot cultures of Verbena officinalis L.
PublikacjaIn vitro shoot cultures of common vervain (Verbena officinalis L., Verbenaceae) were established and evaluated for essential oil content. The shoots were maintained as stationary microshoot culture, grown on Schenk–Hildebrandt medium supplemented with 9.84 µM of 2-isopentenyladenine and 1.0 µM of thidiazuron. The shoots were further adapted to grow in two temporary immersion bioreactors (RITA and Plantform), using Schenk–Hildebrandt...
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PTR-MS and electronic nose application for volatile fraction analysis of cigar tobacco
PublikacjaCigar consumers attach great importance to the quality of these products. At the same time, cigars are often expensive, so destructive analytical methods of quality control are not being desired. However, it has been found that there are many volatile organic compounds in their headspace. Because of that, proton transfer reaction–mass spectrometry and electronic nose were used to analyse it. The obtained results were used to distinguish...
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New procedure for the control of the treatment of industrial effluents to remove volatile organosulfur compounds
PublikacjaWe present a new procedure for the determination of volatile organosulfur compounds in samples of industrial effluents using dispersive liquid–liquid microextraction and gas chromatography with flame photometric detection. Initially, the extraction parameters were optimized. These included: type and volume of extraction solvent, volume of disperser solvent, salting out effect, pH, time and speed of centrifugation as well as extraction...
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Utilization of rapeseed pellet from fatty acid methyl esters production as an energy source
PublikacjaRapeseed pellet – crushed seed residue from oil extraction is a by-product of fatty acid methyl esters production process. As other types of biomass, it can either be burned directly in furnaces or processed to increase its energetic value. Biomass is renewable, abundant and has domestic usage; the sources of biomass can help the world reduce its dependence on petroleum products, fossil coal and natural gas. Energetically effective...
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New procedure for the examination of the degradation of volatile organonitrogen compounds during the treatment of industrial effluents
PublikacjaWe present a new procedure for the determination of 32 volatile organonitrogen compounds in samples of industrial effluents with a complex matrix. The procedure, based on dispersive liquid–liquid microex-traction followed by gas chromatography with nitrogen-phosphorus and mass spectrometric detection, wasoptimized and validated. Optimization of the extraction included the type of extraction and disperser sol-vent, disperser solvent...
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Photocatalytic degradation of volatile and non volatile organics on titanium dioxyde particles in fluidized bed.
PublikacjaPrzeprowadzono degradację metyloetyloketonu w obecności dwutlenku tytanu jako fotokatalizatora. Badano wpływ początkowego stężenia substancji i stężenia fotokatalizatora na szybkość fotokatalitycznego rozkładu.
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An attempt to identify volatile and semi-volatile organic compounds present in the Odra river waters.
PublikacjaCelem pracy była identyfikacja związków z grup lotnych i średniolotnych związkó organicznych. W badaniach wykorzystano technikę Pt-TD-GC-MS. Komputerowa analiza widm masowych wykazała obecność wielu związków organicznych pochodxenia naturalnego i antropogenicznego. W powłokach wód pobranych w okolicy Brzegu Dolnego oznaczono stężenia związków chloroorganicznych na poziomie pojedynczych prób. Nieco wyższe spektrum związków chloroorganicznych,...
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Investigation of volatile low molecular weight compounds formed during continuous reclaiming of ground tire rubber
PublikacjaGround tire rubber was thermo-mechanically reclaimed at different temperature conditions (80, 120, 160 °C) using a co-rotating twin screw extruder. The progress of ground tire rubber reclaiming was evaluated with specific mechanical energy, sol fraction and thermogravimetric analysis. Volatile organic compounds (VOCs) including volatile sulfur compounds (VCSs) released from ground tire rubber and ground tire rubber after reclaiming...
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Ab initio and density functional theory calculations of proton affinities for volatile organic compounds
PublikacjaThe Hatree-Fock method with 6-311G** split-valence molecular orbitals basis sets and the density function theory-B3LYP have been applied to geometrical optimizations and calculations of total electronic, zero point vibrational energies and proton affinities at 298 K for volatile organic compounds. Calculated values of proton affinities are compared with experimental data.
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Prototype of electrochemical sensor for measurements of volatile organic compounds in gases
PublikacjaThe paper presents a laboratory prototype of an electrochemical sensor for measurements of volatile organic compounds (VOCs) in gases, utilizing ionic liquids and commercial screen printed electrodes by DropSens. The following ionic liquids have been tested as the electrolyte and redox reaction environment: 1-butyl, 3-methylimidazolium dicyanoamide ([BMIM][N(CN)2]), 1-octyl, 3-methylimidazolium tetrafluoroborate ([OMIM][BF4]),...
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The use of fungi in biofiltration to remove hydrophobic volatile organic compounds
PublikacjaThe growing importance placed on air quality by environmental regulations and public opinion necessitate the minimization and removal of volatile organic compound emissions (VOCs), including odours. The removal of hydrophobic VOCs from the air by biological methods remains a major technical challenge (despite its importance in the shift to green engineering). A potential solution to this challenge is the use of fungi in biofiltration....
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Microstructural behavior of water-in-oil emulsions stabilized by fatty acid esters of propylene glycol and zinc fatty acid salts
PublikacjaZbadano wpływ składu emulgatorów acylopropylenoglikolowych, modyfikowanych mydłami cynku, na charakter przemian strukturalnych jakim ulegają emulsje W/O stabilizowane przez takie emulgatory. Badano zarówno etap emulgowania jak i mikrostrukturę oraz właściwości reologiczne otrzymanych emulsji.
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Differences between selected volatile aromatic compound concentrations in sludge samples in various steps of wastewater treatment plant operations
PublikacjaSewage sludge, one of the main wastes generated during wastewater treatment, constitutes an important source of emissions of volatile chemical compounds such as volatile aromatic compounds These substances may undergo various changes as a result of operations and unit processes, which affects their concentrations in sewage sludge. An important factor determining the potential hazardousness of volatile organic compounds is the quality...
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Revealing dynamic changes of the volatile profile of food samples using PTR–MS
PublikacjaVolatile compounds carry valuable information regarding the properties of foodstuffs. Volatiles emitted from food can be used as, for example, indicators of quality, shelf-life, or authenticity. A better understanding of the multitude of transformations which occur during food processing could facilitate the optimisation of production, increase the desirability of food products, and also their wholesomeness. However, as some of...
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Bioreactor shoot cultures of Rhododendron tomentosum (Ledum palustre) for a large-scale production of bioactive volatile compounds
PublikacjaRhododendron tomentosum Harmaja (Ledum palustre), a peat bog plant from Ericaceae family, has been used in traditional medicine as the anti-arthritis agent. Although modern researches confirm its anti-inflammatory properties, it remains threatened by habitat degradation and possibilities to collect this endangered species from its natural environment for further biological activity studies are limited. Therefore, R. tomentosum...
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A state of the art review on the use of fungi in biofiltration to remove volatile hydrophobic pollutants
PublikacjaThe physical/chemical abatement of gas pollutants creates many technical problems, is costly and entails significant environmental impacts. Biological purification of off-gases is a cheap and ecologically safe way of neutralization of gas pollutants. Despite the recent advances, the main technological challenge nowadays is the purification of volatile organic compounds (VOCs) of hydrophobic character due to their low solubility...
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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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Online Volatile Compound Emissions Analysis Using a Microchamber/Thermal Extractor Coupled to Proton Transfer Reaction-Mass Spectrometry
PublikacjaIndoor air is a complex and dynamic mixture comprising manifold volatile organic compounds (VOCs) that may cause physiological and/or psychological discomfort, depending on the nature of exposure. This technical note presents a novel approach to analyze VOC emissions by coupling a microchamber/thermal extractor (μ-CTE) system to a proton transfer reaction-mass spectrometer (PTR-MS). This configuration provides an alternative to...
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Chlorogenic acids – their properties, occurrence and analysis
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Study on the concentration of acids by membrane distillation
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Chirality Measures of α-Amino Acids
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ASSESSMENT OF VOLATILE ORGANIC COMPOUNDS EMISSIONS FROM RECYCLED LOW-DENSITY POLYETHYLENE STREAMS
PublikacjaThe recycling of plastics is currently one of the most significant industrial challenges. Due to the enormous amounts of plastic wastes generated by various industry branches, it is essential to look for the potential methods of their utilization. Nevertheless, it should not be forgotten that recycled plastics are not pure materials, and they still may show an unfavorable environmental impact. They may contain different contaminants...
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TMSCL as a rate accelerating additive in acylations of amines with 5-(α- amino-α'-hydroxy)methylene meldrum's acids
PublikacjaAspects are presented of the acylation of amines, alcohols and thiols with 5-(α-amino- α'-hydroxy)methylene Meldrum's acids. We placed special emphasis on the acylation reaction of secondary amines with 5-(α-amino- α'-hydroxy)methylene Meldrum's acids, which, due to their basicity, caused problems concerning salt formation with a Meldrum acid derivative. We found that secondary amines, which react at the slowest rate and with a...
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Tmscl as a rate accelerating additive in acylations of amines with 5-(α-amino- α'-hydroxy)methylene meldrum's acids
PublikacjaAspects are presented of the acylation of amines, alcohols and thiols with 5-(α-amino- α'-hydroxy)methylene Meldrum's acids. We placed special emphasis on the acylation reaction of secondary amines with 5-(α-amino- α'-hydroxy)methylene Meldrum's acids, which, due to their basicity, caused problems concerning salt formation with a Meldrum acid derivative. We found that secondary amines, which react at the slowest rate and with a...
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Multivariate Statistical Analysis for Mutual Dependence Assessment of Selected Polyphenols, Organic Acids and Metals in Cool-Climate Wines
PublikacjaPolyphenols, organic acids and metal ions are an important group of compounds that affect the human health and quality of food and beverage products, including wines. It is known that a specific correlation between these groups exist. While wines coming from the New World and the Old World countries are extensively studied, wines coming from cool-climate countries are rarely discussed in the literature. One of the goals of this...
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Sweet surfactants I: Fatty acid esters of sucralose
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Serum fatty acid profile in psoriasis and its comorbidity
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Removal of Volatile Organic Compounds (VOCs) from Air: Focus on Biotrickling Filtration and Process Modeling
PublikacjaBiotrickling filtration is a well-established technology for the treatment of air polluted with odorous and volatile organic compounds (VOCs). Besides dozens of successful industrial applications of this technology, there are still gaps in a full understanding and description of the mechanisms of biotrickling filtration. This review focuses on recent research results on biotrickling filtration of air polluted with single and multiple...
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Investigations on the removal of hydrophobic odorous volatile organic compounds by biotrickling filtration monitored with electronic nose
PublikacjaThe presented paper presents the results of research on the removal of selected hydrophobic volatile organic compounds (VOCs) from their mixture with air by means of a trickled-bed biofiltration. The efficiency of the removal of toluene and α-pinene, as model VOCs, in a three-section biotrickling filter is evaluated using GCFID and additionally monitored with an electronic nose. The results show that the removal of the model mixture...
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Determination of volatile organic compounds using solventless sample preparation techniques and gas chromatography
PublikacjaIn this paper the latest advances in the determination of volatile organic compounds using solvent-free extraction techniques in the sample preparation step are presented. A paper is focus mainly on one of the most popular sample preparation technique: solid-phase microextraction technique (SPME) combined with different detection systems and its applications to sampling of VOCs from the samples with different matrices. This paper...
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Utilization of oriented crystal growth for screening of aromatic carboxylic acids cocrystallization with urea
PublikacjaThe possibility of molecular complex formation in the solid state of urea with benzoic acid analogues was measured directly on the crystallite films deposited on the glass surface using powder X-ray diffractometry (PXRD). Obtained solid mixtures were also analyzed using Fourier transform infrared spectroscopy (FTIR). The simple droplet evaporation method was found to be efficient, robust, fast and cost-preserving approach for first...
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Monitoring of volatile organic compounds (VOCs) in atmospheric air. Part I. On-line gas analyzers
PublikacjaThe paper reviews the subject literature concerning the analytical instruments routinely used for monitoring volatile organic compounds in atmospheric air. The analyzers are classified as stationary or mobile according to their ease of transport. Stationary DOAS (Differential Optical Absorption Spectroscopy) analyzer is characterized, as are MIMS (Membrane Introduction Mass Spectrometry), MESI (Membrane Extraction with Sorbent...
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Method for the determination of carboxylic acids in industrial effluents using dispersive liquid-liquid microextraction with injection port derivatization gas chromatography–mass spectrometry
PublikacjaThe paper presents a new method for the determination of 15 carboxylic acids in samples of postoxidative effluents from the production of petroleum bitumens using ion-pair dispersive liquid-liquid microextraction and gas chromatography coupled to mass spectrometry with injection port derivatization. Several parameters related to the extraction and derivatization efficiency were optimized. Under optimized experimental conditions,the...
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Organic Acids and Polyphenols Determination in Polish Wines by Ultrasound-Assisted Solvent Extraction of Porous Membrane-Packed Liquid Samples
PublikacjaIn the near future, Poland is going to have more and more favorable conditions for viticulture. Organic acids and polyphenols are among the most commonly analyzed compounds due to their beneficial properties for human health and their importance in the winemaking process. In this work, a new technique involving ultrasound-assisted solvent extraction of porous membrane-packed liquid samples (UASE-PMLS) was for the first time described...
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Key-Marker Volatile Compounds in Aromatic Rice (Oryza sativa) Grains: An HS-SPME Extraction Method Combined with GC×GC-TOFMS
PublikacjaThe 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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Currently Commercially Available Chemical Sensors Employed for Detection of Volatile Organic Compounds in Outdoor and Indoor Air
PublikacjaThe paper presents principle of operation and design of the most popular chemical sensors for measurement of volatile organic compounds (VOCs) in outdoor and indoor air. It describes the sensors for evaluation of explosion risk including pellistors and IR-absorption sensors as well as the sensors for detection of toxic compounds such as electrochemical (amperometric), photoionization and semiconductor with solid electrolyte ones....
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Application of dispersive liquid-liquid microextraction and gas chromatography with mass spectrometry for the determination of oxygenated volatile organic compounds in effluents from the production of petroleum bitumen
PublikacjaWepresent a new procedure for the determination of oxygenated volatile organic compounds in samples of postoxidative effluents from the production of petroleum bitumens using dispersive liquid–liquid microextraction and gas chromatography with mass spectrometry. The eight extraction parameters were optimized for 43 oxygenated volatile organic compounds. The detection limits obtained ranged from 0.07 to 0.82 g/mL for most of the...
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Separation of Volatile Oxygen-containing Organic Compounds by Gas Chromatography - selectivity comparison of different polarity stationary phases
PublikacjaThis paper present a results of the separation of 36 reference compounds belonging to the group of Volatile Oxygen-Containing Organic Compounds (OVOCs) using capillary gas chromatography with flame ionization detector (GC-FID) and three stationary phases of different polarity. A selectivity has been studied regarding to OVOCs and n -alkanes. The most useful for the separation of the group OVOCs is a polar ionic liquid stationary...
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Microscopic Imaging to Visualize the Distribution of Dietary Nucleic Acids in Food Products of Various Origins
PublikacjaDietary nucleic acids (dietNAs) are being increasingly recognized as important food components with nutritional value. However, the precise dietary recommendations for dietNAs are limited, because established methods for determining the quantity and nutritional role of dietNAs are still lacking. One of the tools to narrow this gap could be microscopic imaging, as a convenient approach to visualize the abundance and distribution...
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Analysis of volatile oxidation products in rapeseed oil
PublikacjaCelem pracy było opracowanie metody umożliwiającej określenie stabilności oksydatywnej oleju rzepakowego na podstawie analizy lotnych produktów utleniania lipidów. Na etapie opracowywania metody dobrano optymalne parametry ekstrakcji lotnych analitów techniką SPME. Przeprowadzono również elementy walidacji tej procedury. Zaproponowano też substancje markerowe mogące posłużyć za wyróżniki procesu utleniania lipidów.
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Pervaporation of volatile organohalogen compounds throughpolydimethylsiloxane membrane
PublikacjaThe objective of this work was to apply dense polymeric membranes for pervaporation of tetrachloroethene from aqueous solution. Three membranes were evaluated: polydimethylsiloxane (PDMS-PV1 and PDMSPV2) membranes, and a PDMS with ZSM-5 zeolite filled (PERVAP-1070) membrane. The effect of feed composition on flux and selectivity was also investigated. Tested membranes showed good properties in the separation of tetrachloroethylene,...
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Volatile Compound Emissions from Stereolithography Three-Dimensional Printed Cured Resin Models for Biomedical Applications
PublikacjaStereolithography three-dimensional printing is used increasingly in biomedical applications to create components for use in healthcare and therapy. The exposure of patients to volatile organic compounds (VOCs) emitted from cured resins represents an element of concern in such applications. Here, we investigate the biocompatibility in relation to inhalation exposure of volatile emissions of three different cured commercial resins...
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Novel DNA-binding protein from Nanoarchaeum equitans Kin4-M binds all kinds of nucleic acids
PublikacjaNanoarchaeum equitans is the only known representative of Archaea phylum Nanoarchaeota and stands out as one of the tiniest known living organism. What is more it has smallest genome, which is only 490.885 base pairs long. It is also one of the most compact genomes. According to predictions about 95% of the DNA encodes proteins or stable RNA. Nanoarchaeum equitans lacks genes for most vital metabolic pathways including lipid, cofactor,...
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IDENTIFICATION OF ODOR OF VOLATILE ORGANIC COMPOUNDS USING CLASSICAL SENSORY ANALYSIS AND ELECTRONIC NOSE TECHNIQUE
PublikacjaThe paper compares two methods of analysis of odour of volatile organic compounds: classical sensory analysis and electronic nose technique. Eight volunteers participated in the classical sensory analysis investigations, which lasted two weeks. An instrumental odour analysis involved a prototype of 6-sensor electronic nose designed by the authors. The research performed with this device provided higher reproducibility and reliability...
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Applications of Unnatural Amino Acids in Protease Probes
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Solid-State Modification of Poly(butylene terephthalate) with a Bio-Based Fatty Acid Dimer Diol Furnishing Copolyesters with Unique Morphologies
PublikacjaCopolyesters based on poly(butylene terephthalate) (PBT) and a bio-based fatty acid dimer diol (FADD) were prepared by solid-state modification (SSM). The chemical incorporation of the FADD into the backbone of the PBT was proven using various techniques. It was clear that the incorporation rate was diffusion-limited rather than reaction-limited. From quantitative 13C NMR a nonrandom chemical microstructure was obtained at all...
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The estimation of total volatile organic compounds emissions generated from peroxide cured natural rubber/polycaprolactone blends
PublikacjaNatural rubber (NR)/polycaprolactone (PCL) blends at the ratio of 90/10% wt. (NR/PCL90/10) and 70/30% wt. (NR/PCL70/30), with a constant amount of dicumyl peroxide, were prepared by compounding in an internal mixer. Obtained NR/PCL bio-based blends were cured at three different temperatures (150 °C, 160 °C and 170 °C). The total content of volatile organic compounds (TVOC) as a function of the NR/PCL blends ratio, and their curing...
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Synthesis of polyglycerol esters of fatty acid with defined hydrophilic properties
PublikacjaOtrzymane w odrębnej reakcji mieszaniny poligliceroli poddano estryfikacji kwasami tłuszczowymi oktadekanowym i izooktadekanowym, w obecności odpowiednich mydeł sodu powstających in situ. Zaobserwowano wpływ stężenia karboksylanów sodu oraz budowy kwasu tłuszczowego na przebieg estryfikacji mieszaniny polioli. Stwierdzono, że zastosowany sposób prowadzenia reakcji pozwala zsyntetyzować efektywne emulgatory emulsji O/W, o wartościach...
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TMSCl Promoted Acylation of Amines with 5-(α-amino- α'-hydroxy)methylene Meldrum's Acids - Elucidation of Mechanism.
PublikacjaRecently we have observed accelerating influence of trimethyl silyl chloride addition on the rate of the reactions of 5-(α-amino- α'-hydroxy)methylene Meldrum's Acids with amines, particularly in the case of highly basic amines. However the nature of the aforementioned process remain unexplained. In proposed communication we wish to report insightful elucidation of this mechanism. The reaction under investigation involves simply...
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Impedimetric sensing of α-amino acids driven by micro-patterned 1,8-Diazafluoren-9-one into titania- boron- doped maze-like nanocarbons
PublikacjaThe development of impedimetric, non-faradaic label-free sensors for the detection of α-amino acids constitutes a trailblazing technology for the fast and inexpensive quantification of such biomarkers. Since α-amino acids, such as glycine and sarcosine, are basic constituents in biological processes, a variation in their concentration may be an indicator of cardiovascular diseases and metabolic disorders or neurological conditions....