Novel Mixed-Matrix Pervaporation Membrane Based on Polyether Block Amide Modified with Ho-Based Metal-Organic Framework.

Segmented polymers, such as polyether block amide (PEBA), exhibit unique properties due to the combination of different segments. PEBA consists of soft polyester and rigid polyamide blocks, enabling its use in various industrial applications, including membrane technologies. In this study, PEBA membranes modified with a holmium-based metal-organic framework (Ho-1,3,5-Hbtc) were developed for enhanced pervaporation separation of water/isopropanol and water/phenol mixtures.

Structure and Electrocatalytic Properties of Sulfur-Containing Multi-Walled Carbon Nanotubes on a Titanium Substrate Modified by a Helium Ion Beam.

In this work, a set of analytical techniques, including scanning electron microscopy (SEM), Raman scattering spectroscopy, X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray microanalysis (EDX) and cyclic voltammetry (CV), were used to study the impact of high-energy He ion irradiation on the structural and electrochemical characteristics of sulfur-containing multi-walled carbon nanotubes (S-MWCNTs) placed on a titanium substrate. The results indicate that the ion beam treatment of the S-MWCNT system led to an increase in the level of imperfections on the surface structures of the nanotubes due to the formation of point defects on their outer walls and the appearance of oxygen-containing functional groups, including SO groups, near these defects. At the same time, a significant increase in the sulfur concentration (by 6.

Impact of Metal Source Structure on the Electrocatalytic Properties of Polyacrylonitrile-Derived Co-N-Doped Oxygen Reduction Reaction Catalysts.

The oxygen reduction reaction (ORR) plays a central role in energy conversion and storage technologies. A promising alternative to precious metal catalysts are non-precious metal doped carbons. Considerable efforts have been devoted to cobalt-doped carbonized polyacrylonitrile catalysts, but the optimization of their catalytic performance remains a key challenge.

Evolution of Water State in the "Ionic Liquid EAN/Al(NO)/HO" System Depending on Temperature and Aluminum Salt Concentration.

Although lithium salts are the most successful materials for electrochemical devices so far, there is growing interest in electrolytes containing divalent and trivalent salts, which are characterized by a much higher energy density than lithium systems. For this purpose, the physical and chemical properties of solutions of aluminum nitrate in ethylammonium nitrate (EAN) were studied in a number of works. However, it was demonstrated by the H NMR method that solutions contain water (from aluminum crystallohydrates) in the first solvated shell of the Al cation even after usual drying procedures, and this solvated water cannot be directly detected by the standard Karl Fischer analysis.

Polymer Electrolytes for Supercapacitors.

Because of safety concerns associated with the use of liquid electrolytes and electrolyte solutions, options for non-liquid materials like gels and polymers to be used as ion-conducting electrolytes have been explored intensely, and they attract steadily growing interest from researchers. The low ionic conductivity of most hard and soft solid materials was initially too low for practical applications in supercapacitors, which require low internal resistance of a device and, consequently, highly conducting materials. Even if an additional separator may not be needed when the solid electrolyte already ensures reliable separation of the electrodes, the electrolytes prepared as films or membranes as thin as practically acceptable, resistance may still be too high even today.

NMR Relaxation to Probe Zeolites: Mobility of Adsorbed Molecules, Surface Acidity, Pore Size Distribution and Connectivity.

Unique structural and chemical properties, such as ion exchange, developed inner surface, etc., as well as the wide possibilities and flexibility of regulating these properties, cause a keen interest in zeolites. They are widely used in industry as molecular sieves, ion exchangers and catalysts.

Deep eutectic solvent as stationary phase for flow analysis: Automated trace metal determination in food products.

Background: Deep eutectic solvents (DES) have emerged as effective solvents that address many challenges in analytical chemistry, particularly in microextraction. However, until now, their use has been primarily focused on extraction processes. This has significantly limited their application in analytical chemistry, especially in flow analysis, where the high viscosity of DES has made their use difficult.

SAXS, DLS, and MD studies of the Rg/Rh ratio for swollen and collapsed dendrimers.

The radius of gyration, Rg, and the hydrodynamic radius, Rh, are the main experimental parameters that characterize the size of linear and branched macromolecules. In the case of dendrimers in solution, the ratio Rg/Rh, depending on the global conformation, varies from 1 (for a Gaussian soft sphere) to 3/5 (for a hard sphere). However, for high-generation dendrimers, this ratio may be less than the limiting value for a hard sphere.

[Early measurement of digoxin concentration in blood serum to predict adverse events in older age groups with chronic heart failure and atrial fibrillation.].

To evaluate the effect of early measurement of serum digoxin concentration (SDC) on therapeutical safety and efficacy in patients with recent-onset atrial fibrillation and heart failure. De novo ventricular arrhythmias, high-grade AV node or sinus node blocks were noted in 22%, this risk was positively associated with endpoint SDC (mean SDC 0,88±0,78 ng/mL vs 0,45±0,71 ng/mL, p=0,039) irrespective of baseline characteristics. Empiric calculators for long-term digoxin monitoring correlated with both SDC (r=0,54.

Modulation of Albumin Esterase Activity by Warfarin and Diazepam.

Data are accumulating on the hydrolytic activity of serum albumin towards esters and organophosphates. Previously, with the help of the technology of proton nuclear magnetic resonance (H NMR) spectroscopy, we observed the yield of acetate in the solution of bovine serum albumin and -nitrophenyl acetate (NPA). Thus, we showed that albumin possesses true esterase activity towards NPA.

When a Side Reaction Is a Benefit: A Catalyst-Free Route to Obtain High-Molecular Cobaltocenium-Functionalized Polysiloxanes by Hydroamination.

Cobaltocenium-containing (co)polysiloxanes (Cc-PDMSs) with terminal and side groups were synthesized by the reaction of catalyst-free hydroamination between ethynylcobaltocenium hexafluorophosphate and polysiloxanes comprising amino moieties as terminal and side groups. The conversion of NH groups in the polymers reaches 85%. The obtained (co)polysiloxanes "gelate" due to an increase in their molecular weight by approx.

1-(o-Tolyl)thiourea-based deep eutectic solvent as a stationary phase in flow injection analysis system for mercury and copper determination in edible oils.

In this work, a novel deep eutectic solvent (DES) composed of thymol and 1-(o Tolyl)thiourea 9/1 (mol) is presented for the first time. This DES has not been described in the literature. This DES was first used as a stationary phase in an extraction column integrated into a flow injection analysis system for the simultaneous determination of mercury and copper in edible oils.

Automated liquid-liquid deep eutectic solvents based microextraction procedure for determination of acrylamide in foodstuffs by high-performance liquid chromatography with ultraviolet detection.

Unlabelled: For the rapid and efficient determination of acrylamide in food products by HPLC-UV, an environmentally friendly analytical approach has been developed, including liquid-phase extraction and subsequent liquid-liquid microextraction using a deep eutectic solvent. To automate the procedure, the flow-through "lab in a syringe" method was used. Acrylamide is considered a potential endocrine disrupting chemical and its main source is fried foods, which are widely consumed by both children and adults.

Palladium-Functionalized Polysiloxane Drop-Casted on Carbon Paper as a Heterogeneous Catalyst for the Suzuki-Miyaura Reaction.

In this work, a Pd(II)--cyclometalated complex was grafted to polysiloxanes via azide-alkyne cycloaddition. The obtained polymer-metal complex (Pd-PDMS) acts as a catalyst in the Suzuki-Miyaura reaction. Pd-PDMS was drop-casted onto a carbon fiber support, and the resulting membrane demonstrated catalytic activity in the cross-coupling reaction without yield loss after several catalytic cycles.

Digital color analysis and machine learning for ballpoint pen ink clustering and aging investigation.

Fraudulent activities often involve document manipulation, which poses a significant challenge to forensic science. To address this issue, a novel method was developed that combines intended artificial UV pre-degradation, digital color analysis (DCA) of stroke images, and various machine learning (ML) models. This method can cluster blue ballpoint pen inks and predict their photodegradation time.

The influence of the bounding surface on the structural ordering of short chains of oligoetherimides.

In this study, we have conducted a comparative analysis of the structural ordering of short oligoetherimide chains (dimers) near the bounding surface, depending on the structure of that surface. In order to clarify the possibility of oligoetherimide ordering along the symmetry axes of graphene, two types of bounding surfaces were considered: graphene, with a regular discrete position of interaction centers (carbon atoms), and a smooth, structureless impermeable wall. The chemical structures of the considered dimers consist of two repeating units of BPDA-P3, ODPA-P3, or aBPDA-P3 thermoplastic polyetherimides.

UV-A Flexible LEDs Based on Core-Shell GaN/AlGaN Quantum Well Microwires.

Nanostructured ultraviolet (UV) light sources represent a growing research field in view of their potential applications in wearable optoelectronics or medical treatment devices. In this work, we report the demonstration of the first flexible UV-A light emitting diode (LED) based on AlGaN/GaN core-shell microwires. The device is based on a composite microwire/poly(dimethylsiloxane) (PDMS) membrane with flexible transparent electrodes.

Green-Light Hydrosilylation Photocatalysis with Platinum(II)Metalla-N-Heterocyclic Carbene Complexes.

Platinum(II) metalla-N-heterocyclic carbene complexes featuring pyridyl heterocyclic moiety demonstrate remarkable catalytic efficiency in alkyne hydrosilylation under green light irradiation. The photocatalytic properties of complexes are rationalised by the photo-induced charge transfer occurring in extended condensed system identified with the help of various experimental (UV/vis and emission spectroscopy, cyclic voltammetry) and theoretical methods (DFT/TD-DFT, IFCT analysis).

Advancements in effervescent-assisted dispersive micro-solid phase extraction for the analysis of emerging pollutants.

Emerging pollutants pose an increasing threat to the environment and human well-being, requiring substantial progress in analytical methodologies. Dispersive micro-solid phase extraction (μ-dSPE) has proven successful in detecting and measuring these contaminants, particularly in trace quantities. However, challenges persist in achieving a uniform sorbent distribution and efficient separation from the sample matrix.

Primary alcohol-induced coacervation in alkyl polyglucoside micellar solution for supramolecular solvent-based microextraction and chromatographic determination of phthalates in baby food.

This study reports for the first time the phenomenon of supramolecular solvent formation based on alkyl polyglucoside as an amphiphile and primary alcohol as a coacervation agent. The physical properties (density, kinematic viscosity, phase diagram for ternary system) of the supramolecular solvent were investigated, and a mechanism for its formation was proposed. A green and simple microextraction procedure for preconcentration and determination of phthalates in baby foods packaged in plastic packaging was developed as proof-of-concept example.

Natural deep eutectic solvent for the simultaneous derivatization and microextraction of isoniazid from human plasma.

Background: Personalized medicine is a rapidly revolving field that offers new opportunities for tailoring disease treatment to individual patients. The main idea behind this approach is to carefully select safe and effective medications and treatment plant based on each patient's unique pharmacokinetic profile. Isoniazid is a first-line anti-tuberculosis drug that has interindividual variability in its metabolic processing, leading to significant differences in plasma concentrations among patients receiving equivalent doses.

Supramolecular solvents based on hydrophobic natural deep eutectic solvents and primary amines for preconcentration and determination of enrofloxacin in milk.

In this work, coacervation in primary amines solutions with hydrophobic natural deep eutectic solvents based on terpenoids and carboxylic acids was demonstrated for the first time. A liquid-phase microextraction approach was developed based on supramolecular solvent formation with primary amine acting as amphiphile and hydrophobic deep eutectic solvent making up mixed vesicles and serving as coacervation agent. Such supramolecular solvents could be used to separate wide range of substances from different aqueous media, such as food products, biological liquids and wastewaters.

Iridium(III)-Incorporating Self-Healing Polysiloxanes as Materials for Light-Emitting Oxygen Sensors.

Polymer-metal complexes (PMCs) based on poly(2,2'-bipyridine-4,4'-dicarboxamide-co-polydimethylsiloxanes) with cyclometalated di(2-phenylpyridinato-C,N')iridium(III) fragments and cross-linked by Zn (Zn[Ir]-BipyPDMSs) or Ir (Ir[Ir]-BipyPDMSs) represent flexible, stretchable, phosphorescent, and self-healing molecular oxygen sensors. PMCs provide strong phosphorescence at λ = 595-605 nm. Zn[Ir]-BipyPDMS with PDMS chain length of M = 5000 has the highest quantum yield of 9.

Progress and Challenges of Vanadium Oxide Cathodes for Rechargeable Magnesium Batteries.

Among the challenges related to rechargeable magnesium batteries (RMBs) still not resolved are positive electrode materials with sufficient charge storage and rate capability as well as stability and raw material resources. Out of the materials proposed and studied so far, vanadium oxides stand out for these requirements, but significant further improvements are expected and required. They will be based on new materials and an improved understanding of their mode of operation.

Metabolite responses of cucumber on copper toxicity in presence of fullerene C derivatives.

Copper (Cu) toxicity in crops is a result of excessive release of Cu into environment. Little is known about mitigation of Cu toxicity through the application of carbon-based nanomaterials including water-soluble fullerene C derivatives. Two derivatives of fullerene were examined: polyhydroxylated C (fullerenol) and arginine C derivative.