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Search results for: SUPRAMOLECULAR SOLVENT
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Sulfuric acid modified clinoptilolite as a solid green catalyst for solvent-free α-pinene isomerization process
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Towards azeotropic MeOH-MTBE separation using pervaporation chitosan-based deep eutectic solvent membranes
PublicationDeep eutectic solvents (DESs) are a new class of solvents that can offset some of the major drawbacks of common solvents and ionic liquids. When dealing with the preparation of dense membranes, the use of DESs is still challenging due to their low compatibility with the polymer phase. In this research, a novel L-proline:sulfolane (molar ratio 1:2) DES was synthesized and used for the preparation of more sustainable bio-based membranes...
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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...
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Large-scale DFT calculations in implicit solvent-A case study on the T4 lysozyme L99A/M102Q protein
PublicationW ostatnich latach zaproponowano szereg modeli typu implicit solvent, ktore bazują na bezpośrednim rozwiązaniu niejednorodnego równania Poissona w przestrzeni rzeczywistej. Modele te charakteryzują się elegancją, ponieważ wnęka, w której umieszczona jest molekuła substancji rozpuszczanej zdefiniowana jest bezpośrednio w funkcji gęstości elektronowej, a rozkład ładunku jest w sposób samouzgodniony polaryzowany dzięki reakcji dielektryka,...
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Merging Proline:Xylitol Eutectic Solvent in Crosslinked Chitosan Pervaporation Membranes for Enhanced Water Permeation in Dehydrating Ethanol
PublicationThe scope of this research aims at merging a new deep eutectic mixture (DES) into a biopolymer-based membrane for a pervaporation application in dehydrating ethanol. Herein, an L-proline:xylitol (at 5:1) eutectic mixture was successfully synthesized and blended with chitosan (CS). A complete characterization of the hybrid membranes, in terms of morphology, solvent uptake, and hydrophilicity, has been conducted. As part of their...
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Silent Sonar with matched filtration
PublicationRadars with continuous wave frequency (CW FM sonars) are used in radiolocation as 'silent sonars'. They determine the distance to target by measuring the difference between the frequency of the sounding signal and echo signal. The article presents the principle of operation and parameters of silent CW FM sonars. Target distance determined by these sonars is based on the signal at the output of the matched filter. The Doppler effect...
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Experimental Study of Silent Sonar
PublicationStealth is a frequent requirement in military applications and involves the use of devices whose signals are difficult to intercept or identify by the enemy. The silent sonar concept was studied and developed at the Department of Marine Electronic Systems of the Gdansk University of Technology. The work included a detailed theoretical analysis, computer simulations and some experimental research. The results of the theoretical...
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Comparative Analysis of Salient and Non-Salient Pole Brushless Synchronous Generator for Application in Autonomous Electric Power System
PublicationThis paper presents a comparative study of two types of brushless synchronous generator for application in autonomous electric power systems (e.g. airplane power grid). Commercially used salient pole and a prototype non-salient pole high speed multi-pole brushless synchronous generator (BSG) have been presented. Comparative analysis of both types of the generator has been performed. Chosen simulation (using FEM and circuit models)...
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Unique agreement of experimental and computational infrared spectroscopy: a case study of lithium bromide solvation in an important electrochemical solvent
PublicationInfrared (IR) spectroscopy is a widely used and invaluable tool in the studies of solvation phenomena in electrolyte solutions. Using state-of-the-art chemometric analysis of a spectral series measured in a concentration-dependent manner, the spectrum of the solute-affected solvent can be extracted, providing a detailed view of the structural and energetic states of the solvent molecules influenced by the solute. Concurrently,...
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Effect of Water Content in Ethylene Glycol Solvent on the Size of ZnO Nanoparticles Prepared Using Microwave Solvothermal Synthesis
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Epoxydibenzo[b,f][1,5]diazocines: From a Hidden Structural Motif to an Efficient Solvent-Free Synthetic Protocol
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Effectiveness of various solvent-produced thyme (Thymus vulgaris) extracts in inhibiting the growth of Listeria monocytogenes in frozen vegetables
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Deep Eutectic Solvent Stir Bar Sorptive Extraction: A Rapid Microextraction Technique for the Determination of Vitamin D3 by Spectrophotometry
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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...
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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...
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Fast, solvent-free synthesis of ferrocene-containing organic cages via dynamic covalent chemistry in the solid state
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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,...
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Deep eutectic solvent-based shaking-assisted extraction for determination of bioactive compounds from Norway spruce roots
PublicationPolyphenolic compounds play an essential role in plant growth, reproduction, and defense mechanisms against pathogens and environmental stresses. Extracting these compounds is the initial step in assessing phytochemical changes, where the choice of extraction method significantly influences the extracted analytes. However, due to environmental factors, analyzing numerous samples is necessary for statistically significant results,...
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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...
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Application of ultrasound-assisted solvent extraction of porous membrane packed liquid samples for polyphenols determination in wine samples
PublicationPolyphenols play a crucial role in a proper human health maintenance as well as their presence very often correspond to the quality assessment of producs like wine. Thus, their monitoring is of high interest. However, as they occur in a complex matrices their extraction is very often necessary prior the analysis. Herein, a new ultrasound-assisted solvent extraction of porous membrane packed liquid sample technique has been optimized...
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Morphology control via dual solvent crystallization for high-mobility functionalized pentacene-blend thin film transistors
PublicationWe present an approach to improving the performance of solution processed organic semiconductor transistors based on a dual solvent system. We here apply this to a blend containing the π-conjugated small molecule 6,13 bis(triisopropylsilylethynyl) pentacene (TIPS-pentacene) and polystyrene, which acts as an inert binder. Using a semiconductor-binder solution of two solvents, where the main solvent is a better solvent of the small...
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SOLVENT EXTRACTION AND ION EXCHANGE
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Fuzzy Divisive Hierarchical Clustering of Solvents According to Their Experimentally and Theoretically Predicted Descriptors
PublicationThe present study describes a simple procedure to separate into patterns of similarity a large group of solvents, 259 in total, presented by 15 specific descriptors (experimentally found and theoretically predicted physicochemical parameters). Solvent data is usually characterized by its high variability, dierent molecular symmetry, and spatial orientation. Methods of chemometrics can usefully be used to extract and explore accurately...
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Natural Deep Eutectic Solvents as Agents for Improving Solubility, Stability and Delivery of Curcumin
PublicationPurpose Study on curcumin dissolved in natural deep eutectic solvents (NADES) was aimed at exploiting their beneficial properties as drug carriers. Methods The concentration of dissolved curcumin in NADES was measured. Simulated gastrointestinal fluids were used to determine the concentration of curcumin and quantum chemistry computations were performed for clarifying the origin of curcumin solubility enhancement in NADES. Results NADES...
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Deep eutectic solvents – A new platform in membrane fabrication and membrane-assisted technologies
PublicationDeep eutectic solvents (DESs) are a new class of solvents that can offset some of the primary drawbacks of typical solvents and ionic liquids (ILs). Since DESs fall into the guidelines of “Twelve Principles of Green Chemistry”, their implementation in several types of applications has exponentially increased over the last years. The usage of DESs has been directed to the designing, manufacture and purification of new materials...
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Expectation-Maximization Model for Substitution of Missing Values Characterizing Greenness of Organic Solvents
PublicationOrganic solvents are ubiquitous in chemical laboratories and the Green Chemistry trend forces their detailed assessments in terms of greenness. Unfortunately, some of them are not fully characterized, especially in terms of toxicological endpoints that are time consuming and expensive to be determined. Missing values in the datasets are serious obstacles, as they prevent the full greenness characterization of chemicals. A featured...
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New Screening Protocol for Effective Green Solvents Selection of Benzamide, Salicylamide and Ethenzamide
PublicationNew protocol for screening efficient and environmentally friendly solvents was proposed and experimentally verified. The guidance for solvent selection comes from computed solubility via COSMO-RS approach. Furthermore, solute-solvent affinities computed using advanced quantum chemistry level were used as a rationale for observed solvents ranking. The screening protocol pointed out that 4-formylomorpholine (4FM) is an attractive...
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Evaluation of starch plasticization efficiency by deep eutectic solvents based on choline chloride
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Donor properties of water in organic solvents derived from infrared spectraof HDO
PublicationPrzedyskutowano niektóre ilościowe aspekty kooperatywności wiązań wodorowych wody. Zaproponowano skalę własności elektronodonorowych wody w środowisku aprotycznych rozpuszczalników organicznych, pochodną w stosunku do skali liczb donorowych Gutmanna.
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Catalysts for advanced oxidation processes: Deep eutectic solvents-assisted synthesis – A review
PublicationNew catalyst synthesis techniques, including green materials, are extensively studied for heterogeneous photocatalytic advanced oxidation processes (AOPs) on spotlight of sustainable development. Deep eutectic solvents (DESs) started to be used in this field as environmentally friendly alternative to ionic liquids (ILs). During the catalyst synthesis, DESs can act as stabilizers, capping agents, structure directing agents, templates,...
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Novel “acid tuned” deep eutectic solvents based on protonated L-proline
PublicationThe paper presents new types of deep eutectic solvents (DESs) based on L-proline protonated using three different acids (hydrochloric, sulfuric and phosphoric)and playing the role of a hydrogen bond acceptor(HBA). Glucose and xylitol were used as hydrogen bond donors (HBD). A series of deep eutectic solvents with various mole ratios were obtained for the systems L-proline: glucose and L-proline: xylitol. Density, melting point,...
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New Carvone-Based Deep Eutectic Solvents for Siloxanes Capture from Biogas
PublicationDuring biogas combustion, siloxanes form deposits of SiO2 on engine components, thus shortening the lifespan of the installation. Therefore, the development of new methods for the purification of biogas is receiving increasing attention. One of the most effective methods is physical absorption with the use of appropriate solvents. According to the principles of green engineering, solvents should be biodegradable, non-toxic, and...
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Application of deep eutectic solvents for separation and determination of bioactive compounds in medicinal plants
PublicationThe medicinal plants industry, particularly in regard to products rich in biologically active substances for maintaining health, has grown by leaps and bounds in the last decade, with sales of over-the-counter drugs containing these substances growing by billions of dollars. Attention has thus also been paid to the safety and effectiveness of these medicines. We are currently witnessing a rapid increase in the number of publications...
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Efficient Extraction of Fermentation Inhibitors by Means of Green Hydrophobic Deep Eutectic Solvents
PublicationThe methods for hydrogen yield efficiency improvements, the gaseous stream purification in gaseous biofuels generation, and the biomass pretreatment are considered as the main trends in research devoted to gaseous biofuel production. The environmental aspect related to the liquid stream purification arises. Moreover, the management of post-fermentation broth with the application of various biorefining techniques gains importance....
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Deep Eutectic Solvents as Agents for Improving the Solubility of Edaravone: Experimental and Theoretical Considerations
PublicationIn this study, both practical and theoretical aspects of the solubility of edaravone (EDA) in Deep Eutectic Solvents (DESs) were considered. The solubility of edaravone in some media, including water, can be limited, which creates the need for new efficient and environmentally safe solvents. The solubility of EDA was measured spectrophotometrically and the complex intermolecular interactions within the systems were studied with...
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Deep Eutectic Solvents as Agents for Improving the Solubility of Edaravone: Experimental and Theoretical Considerations
PublicationIn this study, both practical and theoretical aspects of the solubility of edaravone (EDA) in Deep Eutectic Solvents (DESs) were considered. The solubility of edaravone in some media, including water, can be limited, which creates the need for new efficient and environmentally safe solvents. The solubility of EDA was measured spectrophotometrically and the complex intermolecular interactions within the systems were studied with...
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Selected issues related to the toxicity of ionic liquids and deep eutectic solvents—a review
PublicationGreen Chemistry plays a more and more important role in implementing rules of sustainable development to prevent environmental pollution caused by technological processes, while simultaneously increasing the production yield. Ionic liquids (ILs) and deep eutectic solvents (DESs) constitute a very broad group of substances. Apart from many imperfections, ILs and DESs have been the most promising discoveries in the world of Green...
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Possible application of new class of solvents in the purification of water used in hydraulic fracturing
PublicationNowym źródłem energii niekonwencjonalnej w Polsce może być gaz, który jest uwięziony w łupkach. Podczas poszukiwań gazu łupkowego, duże ilości wody wykorzystywanej w procesie szczelinowania hydraulicznego powracają na powierzchnię zanieczyszczone. Istnieje wiele metod usuwania śladowych ilości węglowodorów tj. fizyczne czyli filtracja czy chemiczne czyli zakwaszanie, ale mogą one być nieskuteczne. Pożądana metoda to monitorowanie...
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Metrological parameters of sulphur dioxide amperometric sensor containing addition of aprotic solvents
PublicationW publikacji zaprezentowano wyniki badań nad dodatku rozpuszczalnika aprotycznego do roztworu elektrolitu wewnętrznego czujnika na parametry metrologiczne prototypowego czujnika ditlenku siarki z membraną nafionową. Porównywano właściwości pięciu czujników różniących się składem elektrolitu. W każdym przypadku elektroda pracująca wykonana była ze złota, próżniowo napylonego na powierzchnię membrany. Roztwory elektrolitów zawierały...
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VOCs absorption from gas streams using deep eutectic solvents – A review
PublicationVolatile organic compounds (VOCs) are one of the most severe atmospheric pollutants. They are mainly emitted into the atmosphere from anthropogenic sources such as automobile exhaust, incomplete fuel combustion, and various industrial processes. VOCs not only cause hazards to human health or the environment but also adversely affect industrial installation components due to their specific properties, i.e., corrosive and reactivity....
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Ewa Wagner-Wysiecka dr hab. inż.
PeopleEwa Wagner-Wysiecka is a graduate of the Faculty of Chemistry at Gdańsk University of Technology (specializing in Chemical Technology, with a focus on Inorganic Technology and a sub-specialty in Technical and Industrial Analytics). She completed her master's thesis, entitled "Identification of Contaminants in Pharmacopoeial Sulfaquinoxaline," under the supervision of Professor Jan F. Biernat. After completing her master's degree...
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JABAT Middleware as a Tool for Solving Optimization Problems
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Estimating Intercept Range of Silent Sonar
PublicationWhen used in military application, sonars should ensure secretiveness. There is some evidence suggesting that silent sonars have a significant advantage over pulse sonars in the respect. If improved, the secretiveness of silent sonar translates into the distance over witch its soundings signal are detected by intercept sonars. The article gives estimated distances for far, medium, and short range sonars operating in the oceans...
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Supramolecular structures formed by 2-aminopyridine derivatives. Part I. Hydrogenbonding networks via N-H...N interactions and the conformational polymorphism of N,N´-bis(2-piridyl)aryldiamines
PublicationOtrzymano serię N,N´-bis(2-pirydylo)arylodiamin w postaci monokryształów. Zgodnie z oczekiwaniami, powstawały dwie odmiany polimorficzne. Forma EE z układem wiązań R22(8) figuruje jako jednowymiarowe taśmy. Stwierdzono, że ugrupowanie 2-aminopirydylowe stanowi synton supramolekularny za pomocą którego można projektować struktury w ciele stałym. Właściwości tego syntonu były badane z wykorzystaniem metod dyfrakcyjnych oraz spektroskopii...
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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}]...
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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...
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Organic Acids and Polyphenols Determination in Polish Wines by Ultrasound-Assisted Solvent Extraction of Porous Membrane-Packed Liquid Samples
PublicationIn 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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Molecular Heteroconjugation Equilibria in (n-Butylamine + Acetic Acid) Systems in Binary (Dimethyl Sulfoxide + 1,4-Dioxane) Solvent Mixtures
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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)...
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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...