This study presents the synthesis and characterisation of KH550-modified cardanol-based phenolic hybrid resins. The hybrid resins were prepared via a two-step process: (1) synthesis of cardanol-based phenolic resin (CPR) through the condensation of cardanol and paraformaldehyde (1:1.3 molar ratio of phenolic hydroxyl groups to aldehyde groups), followed by (2) ultrasound-assisted grafting of γ-aminopropyltriethoxy silane (KH550) at varying mass ratios (5 and 15 wt%, denoted as CPR-K5 and CPR-K15, respectively). Hydrolysis of KH550 generated silanol (Si–OH) groups, which underwent covalent grafting and condensation reactions with the phenolic hydroxyl groups (–OH) and hydroxymethyl groups (–CH2OH) of CPR to form Si–O–C crosslinked networks, as confirmed by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). Scanning electron microscopy (SEM) revealed the homogeneous dispersion of the organosilicon phase within the resin matrix. Thermogravimetric analysis (TGA) demonstrated a significant enhancement in thermal stability, with the char yield at 800°C increasing from 7.8% (neat CPR) to 22.1% (CPR-K15). Stress-strain tests verified the enhanced mechanical performance, with the Young’s modulus of CPR-K5 reaching 104.7 MPa (representing a ~512% increase compared to neat CPR, 17.1 MPa) and that of CPR-K15 being 52.2 MPa (~205% increase vs neat CPR). This work provides a facile strategy for preparing sustainable hybrid resins with tailored thermomechanical properties, addressing the inherent brittleness and a low char yield of conventional cardanol-based phenolic resins. The resulting materials show potential for high-temperature structural applications and flame-retardant composites.

This study compares the FT-IR and Raman spectra of amber and other fossil resins from different world regions. The spectra of those resins were analysed based on absorption bands related to the vibrational frequencies of various functional groups present in these compounds. Both spectroscopic methods, FT-IR and Raman, are well-suited for the non-destructive identification of various fossil resins. It was found that FT-IR spectroscopy is particularly suitable for identifying Baltic amber due to its characteristic peak in the 1250–1175 cm–1 wavelength region. Raman spectroscopy can provide helpful information regarding the degree of maturation of resins. The presence of specific Raman bands, such as 1771–1543 and 1510–1400 cm–1, as well as 745 and 696 cm–1, can help determine not only the resin’s maturity but also any structural changes that occurred during burial over the geological time of different lengths.

A new strategy for the preparation of imidazolidine derivatives from reaction of different aromatic ketones with 1,2-ethane diamine in the presence of LiClO4 under the solution phase conditions is described. The products have been obtained in high to excellent yields and appropriate reaction times. The structure of resulting heterocycles has been determined by physical and spectroscopic data.

A new series of 6-(4-fluorophenyl)-2-(substitutedbenzylthio)-4-(furan-2-yl)-1,6-dihydropyrimidine derivatives have been synthesized from 2-acetyl furan through a multi-step reaction sequence. The key intermediate on reacted with various substituted benzyl halides in the presence of K2CO3 afforded a series of title compounds. The structures of all newly synthesized compounds were characterized by IR, 1H NMR, LCMS mass and C, H, N analyses.

A matrix solid-phase dispersion (MSPD) extraction method was applied for three flavones in cranberry (Vaccinium macrocarpon Ait.) matrix for the first time. The optimized MSPD procedure required a small amount of the sample (0.25 g), C18 bonded silica gel (1.0 g) as a dispersant solid-phase sorbent and small volumes of methanol using its aqueous solutions (10 mL) as eluting solvents. Identification and quantification of myricetin, quercetin and kaempferol were performed by HPLC-DAD-MS. The limit of detection varies from 0.04 μg/g to 0.08 μg/g with linear regression coefficients (r2 > 0.999) for each compound. The recoveries of the analytes ranging from 59% to 111% with relative standard deviations less than 9.5% were checked using spiked freezedried cranberry samples. The MSPD method is simple, rapid and efficient for the extraction of flavones from cranberry samples.

In this study, the phosphogypsum waste taken from various places in the factory dump located in Kėdainiai (Lithuania) was reinspected and characterised by different physico-chemical characterisation methods. The results of X-ray diffraction analysis, thermogravimetric analysis and differential scanning calorimetry, Fourier transform infrared spectroscopy, energy-dispersive X-ray analysis, elemental analysis using inductively coupled plasma optical emission and X-ray fluorescence spectroscopy confirmed that the main crystalline phase of the phosphogypsum waste is gypsum (CaSO4·2H2O). The surface morphology of the investigated materials was analysed using scanning electron microscopy. The specific surface area was determined by the Brunauer–Emmet–Teller method. The pore size distribution of the material produced was obtained using the Barrett–Joyner–Halenda method. This study also demonstrated that the phosphogypsum waste could be successfully used as a precursor for the dissolution-precipitation synthesis of high quality bioceramic calcium hydroxyapatite.


 
 
 
 This work demonstrates that an aqueous two-phase system (ATPS) is formed when a small amount of acetonitrile (ACN) is added to the aqueous hexafluoroisopropanol (HFIP) solution. The effect of ACN amount on the volume of the formed HFIP/ACN phase was investigated. It was also shown that relatively hydrophilic methylene blue was completely extracted into the HFIP/ACN phase whereas its extractability with conventional solvents (hexane, CH2Cl2 and CHCl3) was significantly lower. The obtained results suggest that the HFIP/ACN phase exhibits a relatively high polarity and should be a good choice for the extraction of moderately or even highly polar compounds from aqueous samples. Finally, the developed ATPS was applied for the homogeneous liquidliquid microextraction of four cationic dyes from river water samples prior to HPLC analysis. Under optimised extraction conditions, the enrichment factors were around 150. Calibration curves were linear (R2 ≥ 0.9959) for the concentration level between 0.2–0.5 and 50.0 μg/L and the detection limits were in the range 0.05–0.18 μg/L. The recoveries of the dyes for the spiked water samples were 88.6–98.5%, with the relative standard deviation values less than 9.6%.
 
 
 


 
 
 
 The efficient synthesis of 4-alkyl-6-(5-aryl-1,2,3-thiadiazol-4-yl)benzene-1,3-diols as potential isoform-specific Hsp90 inhibitors was developed. The synthetic pathway starts from the commercially available 1,3-benzenediol and employs well-known reactions. The Friedel–Crafts acylation and carbonyl group reduction to the methylene group gave 1-(5-alkyl-2,4-dihydroxyphenyl)-2-arylethan-1-ones. The subsequently carried out condensation with ethyl carbazate and Hurd–Mori cyclisation gave title compounds.
 
 
 

Aqueous tartaric acid-assisted sol–gel preparation technique was successfully applied to synthesise lithium aluminium molybdate with the initial composition of LiAl(MoO4)2. From the results of the thermal analysis and Xray diffraction measurement, the effect of tartaric acid as a ligand on the formation of homogeneous gel precursor was discussed. Besides, X-ray diffraction also revealed the crystallisation of the final LiAlMo2O8 ceramic below the temperature of 400°C. It was found that the initial composition of obtained ceramic significantly affected the formation of the impurity phase defined as AlMo2O12. The Rietveld refinement of the crystalline samples showed the tendency of crystallites growing with the increase of heat-treatment temperature. Similar trends of particle growing were also observed in the images of scanning electron microscopy (SEM) for the corresponding samples heat-treated at different temperatures. Finally, the Fourier-transform infrared spectroscopy (FT-IR) revealed the effect of both the surface morphology and the crystallite size on the intensity of characteristic vibration of the corresponding chemical bonds.

The aim of this study was to show how volatile organic compounds (VOCs) profiling can be used as a method to identify different environments across a city. To achieve that, we employed several methods. First, we carried out the profiling of VOCs in several different locations. Then we identified the marker compounds and their sources. Air samples were collected from 6 different locations within the Vilnius City centre using thermal desorption (TD) tubes. Samples were analysed using thermal desorption coupled with gas chromatography mass spectroscopy (TD/GC-MS) methodology. Compound identification was performed by the library match using the NIST MS Search 2.0 (2005) mass spectral library. The results show how variation in the levels of different VOCs can distinguish between locations within a relatively small area of 2 km2 depending on different emission sources.