Filters
total: 1366
filtered: 1055
displaying 1000 best results Help
Search results for: SOLVENT-ASSISTED EXTRACTED
-
Sulfuric acid modified clinoptilolite as a solid green catalyst for solvent-free α-pinene isomerization process
Publication -
The application of single drop extraction technique for chromatographic determination of solvent residues in edible oils and pharmaceutical products
PublicationW pracy przedstawiono zalety i wady techniki ekstrakcji do pojedynczej kropli, będącą prostą i tanią alternatywą dla mikroekstrakcji do fazy stacjonarnej. Ponadto opisano dwie analityczne procedury do chromatograficznego oznaczania wybranych rozpuszczalników organicznych (heksanu, benzenu, toluenu oraz trichlorometanu, 1,1,1-trichloroetanu, tetrachlorometanu, trichloroetylenu, tetrachloroetenu)w olejach jadalnych i próbkach farmaceutycznych....
-
Validation of SPME-GC and HS-GC procedures for the determination of selected solvent residues in edible oil matrices
PublicationW pracy przedstawiono przebieg procesu walidacji, przeprowadzonej zgodnie ze wskazaniami ICH (International Conference on Harmonization), procedur wykorzystywanych do oznaczania pozostałości wybranych rozpuszczalników w olejach jadalnych i preparatach farmaceutycznych. W celu izolacji i wzbogacania analitów wykorzystano dwie bezrozpuszczalnikowe techniki ekstrakcyjne: ekstrakcję do fazy nadpowierzchniowej (HS) i mikroekstrakcję...
-
Antioxidant potential of various solvent extract from Morus alba fruits and its major polyphenols composition
Publication -
A concerted evolution of supramolecular interactions in a {cation; metal complex; π-acid; solvent} anion-π system
Publication -
Base-Catalyzed, Solvent-Free Synthesis of Rigid V-Shaped Epoxydibenzo[b,f][1,5]diazocines
Publication -
Vibrational spectroscopic studies of N,N'-dimethylpropyleneurea-water system: Affected solvent spectra and factor analysis
PublicationZmierzono widma FT-IR układu N,N'-dimetylopropylenomocznik (DMPU) - woda w całym zakresie składów w zakresie 4000-500 cm-1 przy użyciu techniki całkowitego wewnętrznego odbicia (ATR). Hydratacja DMPU została dodatkowo zbadana przy pomocy transmisyjnej spektroskopii FT-IR izotopowo rozcieńczonej HDO w H2O. Widma zanalizowano przy użyciu ilościowej wersji metody widm różnicowych, prowadzącej do wyizolowania widma rozpuszczalnika...
-
Emissions and toxic units of solvent, monomer and additive residues released to gaseous phase from latex balloons
PublicationThis study describes the VOCs emissions from commercially available latex balloons. Nine compounds are determined to be emitted from 13 types of balloons of different colors and imprints in 30 and 60°C. The average values of total volatile organic compounds (TVOCs) emitted from studied samples ranged from 0.054 up to 7.18 μg∙g-1 and from 0.27 up to 36.13 μg∙g-1 for 30oC and 60oC, respectively. The dataset is treated with principal...
-
A natural deep eutectic solvent - protonated L-proline-xylitol - based stationary phase for gas chromatography
PublicationThe 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...
-
Green, simple analytical method for biogenic amines determination in fruit juice samples using salting-out assisted liquid-liquid microextraction and gas chromatography-mass spectrometry
PublicationSalting-out assisted liquid-liquid microextraction (SALLME) was integrated with the derivatization procedure to establish a one-step sample pre-treatment approach for rapid analysis of 14 biogenic amines (BAs) in fruit juices. The methodology consists of salting-out of analytes, derivatization with ethyl chloroformate (ECF), extraction with ethyl acetate (EtAc), and the analysis of the derivatized BAs using gas chromatography-mass...
-
Investigation of use of hydrophilic/hydrophobic NADESs for selective extraction of As(III) and Sb(III) ions in vegetable samples: Air assisted liquid phase microextraction and chemometric optimization
PublicationIn this paper, a green, cost-effective sample preparation method based on air assisted liquid phase microextraction (AA-LPME) was developed for the simultaneous extraction of As(III) and Sb(III) ions from vegetable samples using hydrophilic/hydrophobic natural deep eutectic solvents (NADESs). Central composite design was used for the optimization of extraction factors including NADES volume, extraction cycle, pH, and curcumin concentration....
-
Combination of homogeneous liquid–liquid extraction and vortex assisted dispersive liquid–liquid microextraction for the extraction and analysis of ochratoxin A in dried fruit samples: Central composite design optimization
PublicationThis paper presents a new analytical procedure based on combination of homogeneous liquid–liquid extraction (HLLE) and vortex-assisted dispersive liquid–liquid microextraction (VA-DLLME) for the accurate and reliable determination of ochratoxin A (OTA) in dried fruit samples. To enable selective extraction of the OTA, six hydrophobic deep eutectic solvents (hDESs) were prepared and tested as extraction solvents. Optimization of...
-
Rotating Magnetic Field-Assisted Reactor Enhances Mechanisms of Phage Adsorption on Bacterial Cell Surface
Publication -
Decisive role of vacuum-assisted carbonization in valorization of lignin-enriched (Juglans regia-shell) biowaste
Publication -
Formation of surface layer in metal matrix composite A359/20SiCP during laser assisted turning
Publication -
Development of New UV–vis Spectroscopic Microwave-Assisted Method for Determination of Glucose in Pharmaceutical Samples
Publication -
Electric field-assisted dissociation of singlet excitons in tris-(8-hydro-xyquinolinato)aluminium (III)
PublicationW pracy podano szczegółowemu badaniu kompleks organo-metaliczny 8-hydroksy-chinoliny i aluminium (ALq3) metodą pomiaru fotopądów i elektromodulacji luminescencji. Stwierdzono, że w obszarze wysokich pól elektrycznych (F>105 V/cm) ładunek wytwarzany jest w procesie dysocjacji wzbudzonych stanów single-towych. Wyjaśnienie przebiegów prądowych w zakresie niskich pól elektrycznych (F<105 V/cm) wymagało włączenia zjawiska rekombinacji...
-
Laser-assisted modification of titanium dioxide nanotubes in a tilted mode as surface modification and patterning strategy
PublicationElectrochemical anodization is regarded as a facile and easily scalable fabrication method of titania nanotubes (TiO2NTs). However, due to the extended duration of calcination and further modifications, much faster alternatives are highly required. As a response to growing interest in laser modification of nanotube arrays, a comprehensive investigation of pulsed-laser irradiation and its effect onto TiO2NT properties has been carried out....
-
Fabrication of ILs-Assisted AgTaO3 Nanoparticles for the Water Splitting Reaction: The Effect of ILs on Morphology and Photoactivity
PublicationThe design of an active, stable and ecient photocatalyst that is able to be used for hydrogen production is of great interest nowadays. Therefore, four methods of AgTaO3 perovskite synthesis, such as hydrothermal, solvothermal, sol-gel and solid state reactions, were proposed in this study to identify the one with the highest hydrogen generation eciency by the water splitting reaction. The comprehensive results clearly show that...
-
Structure-property relationships in peroxide-assisted blends of poly(ε-caprolactone) and poly(3-hydroxybutyrate)
PublicationPoly(ε-caprolactone) and poly(3-hydroxybutyrate) (PCL/PHB) blends in two weight ratios (75/25 and 50/50) were reactively compatibilized in the presence of di-(2-tert-butyl-peroxyisopropyl)-benzene and dicumyl peroxide as free radical initiators. Rheological, mechanical, thermal properties and morphological features, as well as the chemical structure of PCL/PHB blends were investigated. It was found that regardless of PCL/PHB blend...
-
Model Correction and Optimization Framework for Expedited EM-Driven Surrogate-Assisted Design of Compact Antennas
PublicationDesign of compact antennas is a numerically challenging process that heavily relies on electromagnetic (EM) simulations and numerical optimization algorithms. For reliability of simulation results, EM models of small radiators often include connectors which—despite being components with fixed dimensions—significantly contribute to evaluation cost. In this letter, a response correction method for antenna models without connector,...
-
Charge-assisted N(+)–H···(−)S hydrogen bonds in the crystal structure of selected diammonium thiophenolates.
PublicationNew salts of thiophenol with three flexible aliphatic diamines H2N(CH2)nNH2 (n = 2, 4 and 6) have been synthesized and characterized by elemental analyses, IR spectroscopy and X-ray crystallography in order to analyze their supramolecular architecture. Structural analyses indicate that in the crystals, proton transfer has occurred, with the –SH group giving (+)N–H···S(−) hydrogen bonding interaction. The structure of compound 1...
-
Buried Object Characterization Using Ground Penetrating Radar Assisted by Data-Driven Surrogate-Models
PublicationThis work addresses artificial-intelligence-based buried object characterization using 3-D full-wave electromagnetic simulations of a ground penetrating radar (GPR). The task is to characterize cylindrical shape, perfectly electric conductor (PEC) object buried in various dispersive soil media, and in different positions. The main contributions of this work are (i) development of a fast and accurate data driven surrogate modeling...
-
Fast, solvent-free synthesis of ferrocene-containing organic cages via dynamic covalent chemistry in the solid state
Publication -
Solvation of cobalt(II) ion in N,N-dimethylformamide-methanol mixed solvent: calorimetry and VIS spectroscopy studies
PublicationZmierzono entalpie rozpuszczania trifluorometanosulfonianów Co(II) i Na(I) w mieszaninie N,N-dimetyloformamid(DMF)-metanol(MeOH) w całym zakresie jej składu. Z danych tych wyznaczono entalpie przeniesienia jonu Co(II) i jonu trifluorometanosulfonowego. Wyniki zanalizowano za pomocą teorii solwatacji preferencyjnej. Zmierzono również widma w zakresie widzialnym roztworów jonu Co(II) w mieszaninie DMF-MeOH i zanalizowano je, stosując...
-
Effect of Water Content in Ethylene Glycol Solvent on the Size of ZnO Nanoparticles Prepared Using Microwave Solvothermal Synthesis
Publication -
Epoxydibenzo[b,f][1,5]diazocines: From a Hidden Structural Motif to an Efficient Solvent-Free Synthetic Protocol
Publication -
Effectiveness of various solvent-produced thyme (Thymus vulgaris) extracts in inhibiting the growth of Listeria monocytogenes in frozen vegetables
Publication -
Deep Eutectic Solvent Stir Bar Sorptive Extraction: A Rapid Microextraction Technique for the Determination of Vitamin D3 by Spectrophotometry
Publication -
Chemometric determination of solute-affected solvent vibrational spectra as a superior way of information extraction on solute solvation phenomena
PublicationW pracy zaprezentowano dwie chemometryczne metody wyznaczania widm zaburzonych rozpuszczalnika oraz liczby cząsteczek zaburzonych, na podstawie zmierzonych serii wibracyjnych widm FT-IR roztworów substancji. Pierwsza z metod została stworzona na podstawie Namiarowej Analizy Faktorowej (ang. Target Factor Analysis). Druga z nich wykorzystuje algorytm izolacji widm czystych składników z serii widm mieszanin. Działanie obu metod zostało...
-
Development of headspace solid-phase microextraction-gas chromatography method for the determination of solvent residues in edible oils and pharmaceuticals
PublicationW pracy przedstawiono wyniki opracowania procedury oznaczania pozostałości rozpuszczalników organicznych w olejach jadalnych z wykorzystaniem techniki HS-SPME na etapie izolacji i wzbogacania analitów. Przedstawiono proces optymalizacji etapu izolacji i rozdzielenia związków. Dla każdego z analitów wyznaczono parametry walidacyjne charakteryzujące procedurę tj. granice wykrywalności, granicę oznaczalności, liniowość, zakres pomiarowy,...
-
Deep eutectic solvent based method for analysis of Niclosamide in pharmaceutical and wastewater samples – A green analytical chemistry approach
PublicationThe paper presents a simple, but very effective and sensitive spectrophotometric method for trace analysis of Niclosamide based on liquid–liquid microextraction using deep eutectic solvents (DESs) prior to its quantification. Here, different DES systems, such as Choline chloride (ChCl) + Urea, ChCl + Citric acid, ChCl + Ethylene glycol and ChCl + Phenol, were synthesized and evaluated at different molar ratios, selecting ChCl + Phenol...
-
Ocena zasobów eksploatacyjnych w warunkach intensywnego współdziałania ujęć w rejonie Trójmiasta = The admissible volume of extracted groundwater under conditions of intensive interaction between groundwater intakes in Tricity region
PublicationAglomeracja Trójmiejska położona jest na bardzo zróżnicowanym geomorfologicznie obszarze. Wody podziemne ujmowane są zarówno na obszarze wysoczyzny - w strefie zasilania i przepływu wód podziemnych, jak i na obszarze nizin nadmorskich - w strefie ich drenażu. W artykule przestawiono wyniki badań modelowych prowadzonych w celu ustalenia zasobów eksploatacyjnych wód z utworów czwartorzędowych na jednym z ujęć zlokalizowanych w...
-
Efficient optimization approaches for microwave assisted extraction of high-quality antioxidant compounds from Salvia officinalis L.: UHPLC-HRMS differential analysis of phenolic profiles obtained by ultrasound and microwave extraction
PublicationThe study aims to optimize MAE of total phenolic compounds (TPC) and antioxidant capacity from Salvia officinalis L. leaves using a definitive screening design (DSD) and I-optimal design. UHPLC-HRMS analysis was used to identify and compare the composition of MAE and UAE optimal extracts. The results showed that DSD and I-optimal design were successfully applied for the optimization of MAE targeting phenolics and other antioxidants...
-
Molecular Heteroconjugation Equilibria in (n-Butylamine + Acetic Acid) Systems in Binary (Dimethyl Sulfoxide + 1,4-Dioxane) Solvent Mixtures
Publication -
Three-step stacking by field-enhanced sample injection, sweeping, and micelle to solvent stacking in capillary electrophoresis: Anionic analytes
Publication -
Three-step stacking of cationic analytes by field-enhanced sample injection, sweeping, and micelle to solvent stacking in capillary electrophoresis
Publication -
Solvent effects for proton transfer reaction from dimethyl(4-nitrophenyl)malonate to cis 1,2-bis(diethylaminomethyl)cyclohexane
Publication -
Removal of phenolic inhibitor compounds from hydrolysates and post-fermentation broths by using a Hydrophobic Magnetic Deep Eutectic Solvent
Publication -
Deep eutectic solvent (DES) with silver nanoparticles (Ag-NPs) based assay for analysis of lead (II) in edible oils
PublicationThis paper presents an application of silver nanoparticles impregnated by Deep Eutectic Solvents (DES) as ultrasonication aided microextraction system for lead (II) determination in edible oils. The paper presents a systematic optimization of method parameters and examples of its application for analysis of real samples. Maximum recovery for lead (II) extraction was obtained for choline chloride and phenol with a 1:2 molar ratio....
-
Solvent Impact on the Diversity of Products in the Reaction of Lithium Diphenylphosphide and a Ti(III) Complex Supported by a tBu2P–P(SiMe3) Ligand
PublicationWe present two important trends in the reactivity ofthe titanium complex [MeNacNacTi(Cl){η2-P(SiMe3)-PtBu2}](MeNacNac− = [Ar]NC(Me)CHC(Me)N[Ar]; Ar = 2,6-iPr2Ph)with nucleophilic reagents RLi (R = Ph2P,tBuO, (Me3Si)2N, andtBu2N) depending on the reaction medium. Reaction in nonpolarsolvent (toluene) leads to three main products: via an autoredoxprocess and nucleophilic substitution at the Ti-atom to afford theTi(IV) complex [MeNacNacTi(R){η2-P-PtBu2}]...
-
Molecular heteroconjugation equilibria in (n-butylamine + acetic acid) systems in binary (dimethyl sulfoxide + 1,4-dioxane) solvent mixtures
PublicationWyznaczono stałe kwasowe Ka(HA), Ka(BH+) oraz stałe równowagi KAHA-, KBHE+ i KAHB, w układach (n-butyloamina + kwas octowy) bez przeniesienia protonu w binarnych mieszaninach rozpuszczalników (DMSO + 1,4-dioksan). Wartości stałych wyznaczono z wykorzystaniem metody miareczkowania potencjometrycznego przy stałej sile jonowej. Stwierdzono, iż stałe heterokoniugacji molekularnej w badanych mieszaninach rozpuszczalników są liniowo...
-
Electrochemical synthesis of 2D copper coordination-polymers: Layer-stacking deviation induced by the solvent and its effect on the adsorptive properties
PublicationA 2D Cu-based Metal-Organic Framework (MOF), namely copper-terephthalate (Cu(1,4-BDC)), was successfully synthesized by electrochemical method for effective methylene blue (MB) sorption from aqueous solutions. The composition, morphology, and the presence of functional groups in the obtained material were verified by Fourier Transform Infrared spectroscopy (FTIR), Powder X-Ray Diffraction (PXRD), Thermal (TGA), and Elemental (EA)...
-
A Cu/Zn heterometallic complex with solvent-binding cavity, catalytic activity for the oxidation of 1-phenylethanol and unusual magnetic properties
PublicationMononuclear and polymeric complexes of zinc(II) and copper(II) have been synthesized using two isomers of the hemi-salen ligand with a different mutual orientation of donor atoms. The heterometallic Cu/Zn metallocycle features a catalytic niche filled with the molecule of water and molecules of methanol. This unusual compound exhibits both pronounced catalytic activity in the reaction of oxidation of a secondary alcohol to ketone...
-
Improved Consensus-Fragment Selection in Template-Assisted Prediction of Protein Structures with the UNRES Force Field in CASP13
Publication -
Low-energy (0.1 eV) electron attachment S?S bond cleavage assisted by Coulomb stabilization
Publication -
An Assessment of RASSCF and TDDFT Energies and Gradients on an Organic Donor−Acceptor Dye Assisted by Resonance Raman Spectroscopy
PublicationThe excitation energies and gradients in the ground and the first excited state of a novel donor−(π- bridge)−acceptor 4-methoxy-1,3-thiazole-based chromophore were investigated by means of MS-RASPT2/RASSCF and TDDFT in solution. Within both methods, the excitation energies strongly depend on the employed equilibrium structures, whose differences can be rationalized in terms of bond length alternation indexes. It is shown that functionals with...
-
On Decomposition-Based Surrogate-Assisted Optimization of Leaky Wave Antenna Input Characteristics for Beam Scanning Applications
PublicationRecent years have witnessed a growing interest in reconfigurable antenna systems. Travelling wave antennas (TWAs) and leaky wave antennas (LWAs) are representative examples of structures featuring a great level of flexibility (e.g., straightforward implementation of beam scanning), relatively simple geometrical structure, low profile, and low fabrication cost. Notwithstanding, the design process of TWAs/LWAs is a challenging endeavor...
-
Multifunctional catalyst-assisted sustainable reformation of lignocellulosic biomass into environmentally friendly biofuel and value-added chemicals
PublicationRapid urbanization is increasing the world's energy demand, making it necessary to develop alternative energy sources. These growing energy needs can be met by the efficient energy conversion of biomass, which can be done by various means. The use of effective catalysts to transform different types of biomasses will be a paradigm change on the road to the worldwide goal of economic sustainability and environmental protection. The...
-
Solvation of cobalt(II) and trifluoromethanesulfonate ions in N,N-dimethylformamide-methanol mixed solvent studied by means of FT-IR spectroscopy
PublicationWidma FT-IR roztworów Co(CF3SO3)2-N,N-dimetyloformamid-metanol były analizowane w zakresie pasm CO i OH za pomocą metody widm różnicowych. Wyznaczono liczbę cząsteczek DMF i MeOH w pierwszej sferze solwatacji jonu Co(II) w zależności od składu rozpuszczalnika. Stwierdzono także obecność drugiej sfery solwatacji jonu Co(II) i scharakteryzowano ją ilościowo. Zbadano również solwatację jonu tifluorometanosulfonowego oraz asocjację...