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Wyniki wyszukiwania dla: SOLUTION CHEMISTRY
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Enzyme-conjugated MXene nanocomposites for biosensing and biocatalysis acuities
PublikacjaEngineered two-dimensional (2-D) MXenes-based materials with tunable characteristics and multi-functionalities have brought up new paradigms in the biosensing and catalysis of chemical compounds. The profusion of electroactive functional moieties on the surface of few/multi-layer MXenes facilitates their ability to retain biomolecules such as enzymes resulting in unique dimensions for bioanalytical and biosensing applications....
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Rainwater chemistry composition in Bellsund: Sources of elements and deposition discrepancies in the coastal area (SW Spitsbergen, Svalbard)
PublikacjaDiscrepancies in rainfall chemistry in Bellsund were found to be influenced by the orographic barrier and related to the variability in the inflow of air masses as well as to the distance of sampling sites from the sea and thus the extent of sea spray impact. This study covers measurements of rainfall (P) and air temperature (T), physicochemical parameters (pH, specific electrolytic conductivity (SEC), major ions (Cl , NO3 , SO4...
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Application of modern sample-preparation techniques to the determination of chloropropanols in food samples
PublikacjaChloropropanols are heat-induced food toxicants that recently caused concern among industrial and scientific experts. World and European organizations related to food safety asked researchers to investigate mitigation strategies regarding these contaminants. The essential objective of this project was development of fast analytical methods enabling reliable determination and quantification of 3-monochloropropane-1,2-diol, 2-monochloropropane-1,3-diol...
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Developments in Green Chromatography
PublikacjaGreen analytical chemistry is a widely recognized concept that has led to the development of new analytical methods with reduced environmental impact and minimized analyst occupational exposure. Achievements include the development of microextraction, ultrasound-assisted extraction (UAE), and microwave-assisted extraction (MAE) techniques. Research towards greener separation processes focuses on the elimination of toxic solvents...
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Green aspects of techniques for the determination of currently used pesticides in environmental samples
PublikacjaPesticides are among the most dangerous environmental pollutants because of their stability, mobility and long-term effects on living organisms. Their presence in the environment is a particular danger. It is therefore crucial to monitor pesticide residues using all available analytical methods. The analysis of environmental samples for the presence of pesticides is very difficult: the processes involved in sample preparation are...
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Dynamic Headspace Sampling as an Initial Step for Sample Preparation in Chromatographic Analysis
PublikacjaThis work represents a brief summary of the use of dynamic headspace (DHS) as a technique for sample preparation in chromatographic analysis. Despite numerous developments in the area of analyte isolation and enrichment, DHS remains one of the fundamental methods used with GC. In our opinion, interest in this technique will not diminish significantly because it conforms to stipulations of green analytical chemistry. Moreover, DHS...
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Mid-infrared spectroscopy for characterization of Baltic amber (succinite)
PublikacjaNatural Baltic amber (succinite) is the most appreciated fossil resin of the rich cultural traditions dating back to prehistoric times. Its unequivocal identification is extremely important in many branches of science and trades including archeology, paleontology, chemistry and finally mineralogical and gemological societies. Current methods of modification of natural succinite are more and more sophisticated making the identification...
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Quantitative assessment
PublikacjaThe main trends in the development of analytical chemistry are the determination of increasingly lower concentrations of analytes in samples with complex matrix composition (trace analysis). While the obtained analytical results must be reliable, which means that they must accurately (truly and precisely) reflect the actual content of analytes in a representative sample of the material object under study. However, it is an extremely...
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Selected Methods for the Chemical Phosphorylation and Thiophosphorylation of Phenols
PublikacjaThis Focus Review gathers together a selection of methods for the chemical phosphorylation of phenols that employ three‐ and four‐coordinate phosphorus compounds. Phosphorylated scaffolds can exhibit enhanced properties compared to their non‐phosphorylated analogues, such as increased biological activity and increased/decreased solubility; as such, phosphorus compounds have gained more and more interest in organic and medicinal...
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Complexation of amino acids derivatives in water by calix[4]arene phosphonic acids
PublikacjaSeries of the calix[4]arene phosphonic acids with various substituents at the lower rim was synthesized. Complexing properties of these receptors towards methyl esters of six amino acids strongly depended on the calix[4]arene conformation flexibility. The complex formation processes were monitored using 1H NMR spectroscopy (deuterated phosphate buffer at pD 7.3, 22 oC) and association constant values were evaluated. Inherently...
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Plant-based meat substitute analysis using microextraction with deep eutectic solvent followed by LC-MS/MS to determine acrylamide, 5-hydroxymethylfurfural and furaneol
PublikacjaFor the analysis of plant-based meat substitutes and the determination of Maillard reaction products such as acrylamide, 5-hydroxymethylfurfural and furaneol, a novel and effective procedure based on hydrophobic natural deep eutectic solvent and liquid chromatography coupled with tandem mass spectrometry was developed for the first time. The 49 compositions of the deep eutectic solvents were designed and screened to select the...
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Remote Sensing Methods In the Study of the Impact of Long-Term Process of Sulphur Mining on Environmental Changes of the Carpathian Foreland
PublikacjaThe paper presents research on the extent of impact of sulphur mining process and post-mining activities upon properties of selected elements of the environment, as well as the assessment of the influence of indirect effects resulting from many years' process of exploitation of sulphur deposits in the areas of the Carpathian Foreland (south-east Poland). Within the scope of research conducted, the assessment of the extent of...
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Analysis of odor interactions in ternary gas mixtures using electronic nose
PublikacjaIn recent years there has been a noticeable increase in interest in the use of electronic noses in analytical chemistry. These devices perform a holistic analysis of the gas mixtures composition, without the separation and identification of its individual components. For this reason e-noses are increasingly replacing the conventional olfactometers, due to the significantly shorter analysis time and possible automation. In the work...
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Microwave treatment in waste rubber recycling – recent advances and limitations
PublikacjaEnvironmentally-friendly microwave heating is increasingly used in polymer chemistry and technology. The selectivity and highly efficiency in the heat transfer present a huge advantage in systems based on recycling, improving their productivity and economic competitiveness. In case of the industrial recycling of waste rubbers, especially end-of-life tires, microwave-induced devulcanization and pyrolysis are nowadays considered...
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Polyisocyanates from Sustainable Resources
PublikacjaIsocyanates, next to polyols, constitute the major components essential for polyurethane (PU) production. They have a significant impact on physicochemical, mechanical, and thermal properties of PU materials. They also have an impact on those materials’ purposes, forms, textures, and other features. The available and used isocyanates are of a petrochemical origin. With the development of a trend toward green chemistry in the science...
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Chemometrics approaches to green analytical chemistry procedure development
PublikacjaChemometric tools are widely used in analytical chemistry for the reduction of data dimensionality, grouping of variables and processing of analytical signals. They have also the potential to be applied in analytical procedure development with the aim of minimizing the procedure’s environmental impact. The design of experiment gives the possibility to obtain much better information on the system response than in case of “changing...
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Reemission of inorganic pollution from permafrost? A freshwater hydrochemistry study in the lower Kolyma basin (North-East Siberia)
PublikacjaPermafrost regions are under particular pressure from climate change resulting in widespread landscape changes, which impact also freshwater chemistry. We investi- gated a snapshot of hydrochemistry in various freshwater environments in the lower Kolyma river basin (North-East Siberia, continuous permafrost zone) to explore the mobility of metals, metalloids and non-metals resulting from permafrost thaw. Partic- ular attention...
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Fluorine ions in photocatalysts’ synthesis: an obstacle or an ally? The investigation of photocatalysts in Ti-O-F system
PublikacjaTitanium(IV) oxide (TiO2) is one of the most promising photocatalysts, which is expected to be applied in the photocatalytic degradation of xenobiotics. For sustainable development and green chemistry approach recently, much effort has been paid to enhance TiO2 photocatalytic activity in UV-vis light by modifying its structure. The photocatalytic process’s complexity cannot be simply described as electron-hole pairs generations...
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Local Structure and Stability of SEI in Graphite and ZFO Electrodes Probed by As K-edge Absorption Spectroscopy
PublikacjaThe evolution of the solid electrolyte interphase (SEI) during the first Li uptake in advanced Li-ion electrodes is studied by X-ray absorption spectroscopy (XAS). The As atoms present in the electrolyte solution were used as a local probe for monitoring the SEI growth on different electrodes. High-quality As K-edge spectra were collected in fluorescence mode for a set of graphite and carbon-coated ZnFe2O4 electrodes. XAS measurements...
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Modulated crystal structures - periodicity in more than three dimensions
PublikacjaThe initial definition of a crystal was that it is an object with flat faces. When diffraction studies were developed it turned out that crystal consists of a highly ordered particles and it is possible to isolate a small unique part of their structure - a unit cell - and the definition has been changed to rely on this fact. Nowadays by a crystal we mean any solid having an essentially discrete diffraction diagram. It is because...
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Green aspects of techniques for the determination of pesticides in fruits and vegetables
PublikacjaApplied all over the world, pesticides are some of the most dangerous pollutants of the environment because of their stability, mobility, their ability to accumulate in the environment and their consequent long-term adverse effects on living organisms in general and human health in particular. Their presence in the environment is a particular danger. It is therefore crucial to monitor pesticide residues using all available analytical...
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Oznaczanie śladowych ilości związków organicznych w próbkach o złożonych matrycach zgodne z regułami ''zielonej chemii analitycznej''. Krótkołańcuchowe kwasy karboksylowe = Increasingly green approaches to the determination of selected trace organic in complex matrices. Short chain carboxylic acids
PublikacjaNowadays the great stress is put on environment protection and the activities to minimize the effect of chemical analyses on the environment are discussed. When environmentally friendly methodologies of analytes determination are applied the term "green analytical chemistry" is used. In general, the determination of organic compounds in complex matrices, which is a frequent analytical task, requires separation of sample components...
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1,3-alternate calix[4]arene-bonded silica stationary phases. Effect of calixarene skeleton substituents on the retention mechanism and column selectivity
PublikacjaFour novel 1,3-alternate calix[4]arene-bonded silica gel stationary phases possessing different aromatic and aliphatic substituents at the upper rim (CalixNph, CalixBph, CalixHex and CalixDdc) were prepared and structurally characterized. The comparison and selectivity of these phases was done by using alkylbenzenes, fatty acid p-bromophenacyl esters, aromatic positional isomers and polynuclear aromatic hydrocarbons as analytes....
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Problematyka dotycząca zapewnienia fotostabilności substancji leczniczych w postaciach leku
PublikacjaUV and visible radiation may influence on the stability of some active pharmaceutical ingredients and in a consequence destabilizes such medicinal products, causes changesin its physicochemical properties also with negative pharmacological and sometimes even toxic effects. For this reason it is important to conduct the routine testing photostability. The knowledge of chemistry and technology as well as some methods of...
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Binder-induced surface structure evolution effects on Li-ion battery performance
PublikacjaA comparative investigation on binder induced chemical and morphological evolution of Li4Ti5O12 electrodes was performed via X-ray photoemission spectroscopy, scanning electron microscopy, and electrochemical measurements. Composite electrodes were obtained using three different binders (PAA, PVdF, and CMC) with 80:10:10 ratio of active material:carbon:binder. The electrochemical performances of the electrodes, were found to be...
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Application of deep eutectic solvents in bioanalysis
PublikacjaThe application of deep eutectic solvents (DESs) is sharply surging as a green alternative to conventional solvents due to their unique properties in terms of simplicity of preparation, designability and low cost. A great deal of attention has been paid to the application of these green solvents in analytical chemistry in recent years, and a lot of interesting work has been reported. This review summarizes the most relevant applications...
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What is in a name: Defining “high entropy” oxides
PublikacjaABSTRACT High entropy oxides are emerging as an exciting new avenue to design highly tailored functional behaviors that have no traditional counterparts. Study and application of these materials are bringing together scientists and engineers from physics, chemistry, and materials science. The diversity of each of these disciplines comes with perspectives and jargon that may be confusing to those outside of the individual fields,...
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Structural and Material Determinants Influencing the Behavior of Porous Ti and Its Alloys Made by Additive Manufacturing Techniques for Biomedical Applications
PublikacjaOne of the biggest challenges in tissue engineering is the manufacturing of porous structures that are customized in size and shape and that mimic natural bone structure. Additive manufacturing is known as a sufficient method to produce 3D porous structures used as bone substitutes in large segmental bone defects. The literature indicates that the mechanical and biological properties of scaffolds highly depend on geometrical features...
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Expectation-Maximization Model for Substitution of Missing Values Characterizing Greenness of Organic Solvents
PublikacjaOrganic 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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Beneficial effects and potential risks of tomato consumption for human health: An overview
PublikacjaTomato and its derived products have a very interesting nutritional value in addition to prominent antioxidant,anti-inflammatory, and anticancer activities. In terms of tomatoes are generally quite safe to eat. However,overall consumption varies from individual to individual. Indeed, either beneficial or harmful effects of plantsor their derived products are closely related to quality, including the presence of biologically active...
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Diethyl carbonate as a green extraction solvent for chlorophenol determination with dispersive liquid–liquid microextraction
PublikacjaThe principles of green analytical chemistry indicate that the search for greener organic solvents for extraction applications is crucial. In this study diethyl carbonate (DEC) is proved to be a green solvent, as it is relatively nontoxic, obtainable from renewable resources and biodegradable. Here it is applied as an extraction solvent for chlorophenol determination in water samples with dispersive liquid–liquid microextraction....
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Evaluation of polycaprolactone as a new sorbent coating for determination of polar organic compounds in water samples using membrane–SPME
PublikacjaCommercially available solid-phase microextraction fibers used for isolation of polar analytes are based on the adsorption phenomenon. In consequence, typical limitations bonded with analytes displacement and matrix effects are very frequent. In the present study, alternative solution is described. Polycaprolactone (PCL) was used for the first time as sorbent to isolate polar organic compounds from water samples using the membrane–solid-phase...
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Experimental and Quantum Chemical Evaluation of 8-Hydroxyquinoline as a Corrosion Inhibitor for Copper in 0.1 M HCl
PublikacjaThe corrosion inhibition properties of 8-hydroxyquinoline (8-HQ) in 0.1 M HCl for copper have been investigated by using experimental (electrochemical impedance spectroscopy (EIS), dynamic electrochemical impedance spectroscopy (DEIS), and potentiodynamic polarization) and theoretical methods complemented by surface morphological examination with the aid of scanning electron microscopy (SEM) and electron dispersive X-ray spectroscopy...
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Dew Formation and Chemistry Near a Motorway in Poland
PublikacjaIn this study, the influence of traffic intensity on dewformation efficiency and chemistry is presented. The measurementswere conducted near the A4 motorway in SW Poland in almost flatland relief with intense agricultural activity. The dew/hoarfrost wascollected by means of insulated plain passive radiative condensersat three sites: AN and AS located in the close vicinity of themotorway (30 m) on the opposite sides of the road,...
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Application of passive sampling techniques as a usable tool in the field of environmental quality monitoring
PublikacjaAnalysis of literature data published for the past 20 years leads to the conclusion, that passive sampling technique has been developing very quickly and is commonly used in the field of monitoring pollutants in air, water and soil environment. The popularity of application of passive sampling techniques in analytical and environmental chemistry results from its many advantages e.g.: Simplicity in use, low costs of exploitation,...
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Bibliometric analysis and literature review of ultrasound-assisted degradation of organic pollutants
PublikacjaUltrasound as a clean, efficient, and cheap technique gains special attention in wastewater treatment. Ultrasound alone or coupled with hybrid processes have been widely studied for the treatment of pollutants in wastewater. Thus, it is essential to conduct a review about the research development and trends on this emerging technique. This work presents a bibliometric analysis of the topic associated with multiple tools such as...
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Pharmaceutical and forensic drug applications of chiral supercritical fluid chromatography
PublikacjaTHE SUPERCRITICAL FLUID IS AN EXCELLENT CHOICE AS THE CHROMATOGRAPHIC MOBILE PHASE BECAUSE IT ALLOWS RAPID SEPARATION WITH HIGH EFFICIENCY AND APPLICATIONS INVOLVING ENANTIORESOLUTION ARE COMMON. SUPERCRITICAL FLUID CHROMATOGRAPHY (SFC) IS INCREASINGLY USED FOR ANALYTICAL, SEMI-PREPARATIVE AND PREPARATIVE PURIFICATION OF CHIRAL COMPOUNDS, INCLUDING PRODUCTION OF ENANTIOMERS THAT ARE MAINLY ENCOUNTERED DURING DRUG DEVELOPMENT. SFC...
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Application of magnetic nanoparticles for magnetic solid-phase extraction in preparing biological, environmental and food samples
PublikacjaThe need to obtain meaningful results as the basis for determining the content of trace amounts of analytes has become the driving force behind the development of modern analytical techniques, including sample-preparation techniques, such as solid-phase extraction (SPE). Recently, great interest was aroused in the use of magnetic nanoparticles (MNPs) in SPE. These materials exhibit high selectivity, and, in small amounts, can provide...
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A large family of filled skutterudites stabilized by electron count
PublikacjaThe Zintl concept is important in solid-state chemistry to explain how some compounds that combine electropositive and main group elements can be stable at formulas that at their simplest level do not make any sense. The electronegative elements in such compounds form a polyatomic electron-accepting molecule inside the solid, a ‘polyanion’, that fills its available energy states with electrons from the electropositive elements...
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Synthesis, Structure and Properties of Poly(ester-Urethane-Urea)s Synthesized Using Biobased Diamine
PublikacjaModern polymer science and technology is focused on the development of partial or fully green polymers. This focus is related to green chemistry trends, which propose using natural and renewable resources as monomers in the synthesis of polymers. In this study, biobased diamine was used as a chain extender of ester-urethane prepolymer. Obtained poly(ester-urethane-urea) contains 16 wt% of biobased diamine. There is mention of an...
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Indoor air quality in public utility environments-a review
PublikacjaIndoor air quality has been the object of interest for scientists and specialists from the fields of science such as chemistry, medicine and ventilation system design. This results from a considerable number of potential factors, which may influence the quality of the broadly understood indoor air in a negative way. Poor quality of indoor air in various types of public utility buildings may significantly affect an increase in the...
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Problems and chellenges to determine pesticide residues in bumblebees
PublikacjaBumblebees play an important role in t he pollination process of many crops and flowers. Therefore, taking action to protect and assess the impact of p esticides on these insects is fully justi fied. Pesticides may cause mortality and also sub-lethal effects that are not always directly visible. Bumblebees, like honeybees, can be used as indicators for environmental monitoring contamination. Two approaches are mainly used for the...
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The role of analytical chemistry in the study of the Anthropocene
PublikacjaThe term “Anthropocene” refers to not yet formalized epoch of geologic time during which geologic processes have been dominated by the human impact. This impact takes on many forms. Biological, physical and chemical changes to the Earth System caused by anthropogenic activity are recorded in natural archives either as new fossil assemblages (neobiota), anthropogenic deposits or a wide variety of pollutants emitted to the environment....
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Application of additional factors supporting the microextraction process
PublikacjaDue to the fact that green analytical chemistry is of high importance, the past two decades have witnessed a rapid growth in the sample preparation area with special emphasis on simplification, miniaturization and automation of extraction procedures. In addition, to accelerate the extraction processes and to improve the separation of analytes, several enhanced parameters are applied. These factors include, ultrasounds, microwaves,...
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Preparation and characterisation of iron substituted Mn1.7Cu1.3-xFexO4 spinel oxides (x = 0, 0.1, 0.3, 0.5)
PublikacjaSpinel oxides with the general formula Mn1.7Cu1.3-xFexO4 (x= 0, 0.1, 0.3, 0.5) were prepared and evaluated in this work for their properties at high temperatures. The effect of partially substituting Cu by Fe has not been studied so far for this group of materials and is thus evaluated in this work. Mn1.7Cu1.3-xFexO4 powders were synthesised by a soft chemistry process and studied in terms of crystallographic phase analysis, electrical...
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Surfactants application in sample preparation techniques: Insights, trends, and perspectives
PublikacjaSince the implementation of Green Chemistry into analytical practice, significant efforts have been made to improve the sustainability of chemical analysis. These include reducing the use of hazardous chemicals and solvents, minimizing waste, and improving energy efficiency. Surfactants can be applied in chemical analysis as an environmentally friendly alternative to conventional solvents and chemicals. The use of surfactants can...
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Calculation of Vibrational Resonance Raman Spectra of Molecules Using Quantum Chemistry Methods
PublikacjaThe understanding and interpretation of experimental resonance Raman (RR) spectra can strongly benefit from theoretical simulations. These can be achieved by combining quantum chemistry (QC) methods to calculate the electronic and vibrational molecular properties, together with appropriate models and approximations to compute the Raman intensities. This chapter presents the main and most commonly employed approaches to calculate...
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Liquid–phase microextraction: A review of reviews
PublikacjaSample preparation is an important step in chemical analysis. It is generally done to deal with problems associated with the nature of the matrix, low analyte concentrations in real samples or analyte features incompatible with the instrumentation. Classical methods of extraction consume large volumes of hazardous solvents and other reagents and are not in line with the recent emergence of green analytical chemistry. Liquid-phase...
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Electron interactions with Bis(pentamethylcyclopentadienyl) titanium(IV) dichloride and difluoride
PublikacjaWe present a combined experimental and theoretical study of the interaction of electrons with Bis(pentamethylcyclopentadienyl)titanium(IV) dichloride (Cp∗2TiCl2) and difluoride (Cp∗2TiF2). We report the experimental measurements of partial cross sections for the dissociative electron attachment (DEA) and the electron ionization (EI) mass spectra of isolated molecules. Estimates of the absolute cross sections are done on the basis...
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Reduced Graphene Oxide Joins Graphene Oxide To Teach Undergraduate Students Core Chemistry and Nanotechnology Concepts
PublikacjaNovel carbon nanomaterials such as reduced graphene oxide (rGO) and graphene oxide (GO) can be easily incorporated into the undergraduate curriculum to discuss basic chemistry and nanotechnology concepts. This paper describes a laboratory experiment designed to study the differences between GO and rGO regarding their physico-chemical properties (e.g. color, hydrophobicity, type of functional groups, electrical conductivity etc.)....