Elemental Analysis Research Articles

Features of Carbon Forms Distribution in Peat Deposits of an Oligotrophic Bog in the Kondinsky Lakes Nature Park

Wetland ecosystems play a key role in the global carbon cycle, accumulating significant amounts of carbon and influencing climate processes. The study of the dynamics of carbon accumulation, dissolved organic carbon (DOC) and the stratigraphy of peat deposits allows us to assess the impact of climate change on wetlands. The results of the work are important for predicting the response of ecosystems to global warming and developing measures for their conservation. In this study, we examined three stratigraphic profiles and the composition of dissolved organic matter (DOM) of undisturbed areas of an oligotrophic bog in the Kondinskie Lakes Nature Park. The aim of this study was to assess the influence of the botanical composition and physicochemical parameters of the peat deposit on the amount and composition of dissolved organic carbon (DOC). To attain this aim, the following tasks were set: to determine the physicochemical characteristics of peat, study the stratigraphy of the peat deposit and determine the content of organic carbon, the concentration and composition of DOC in the peat deposit. Peat cores were collected in the spring (March 2023). The depth of the peat deposit varied within 3.5-4 m. In this paper, the following methods were used: stratigraphic method, peat moisture determination, elemental analysis of organic carbon, pH, determination of spectral characteristics, calculation of organic carbon reserves, moisture index (MI) and active soil richness and salinity (RS) indices according to the L.G. Ramensky scales. Peat moisture content was determined by the difference in the mass of the wet and dry sample. Total organic carbon content was determined by the EA-3000 elemental analyzer. Dissolved organic carbon was determined by a Flash-2000 elemental analyzer (Thermo Scientific, USA). A binocular microscope (10-40× magnification; Zeiss Axiostar, Jena, Germany) was used to determine plant residues and the degree of decomposition. The methodology was carried out in accordance with the protocols [Mauquoy, Van Geell, 2013] using a database of key samples, i.e. a collection of plant residues that were found in the region and used to determine the botanical composition of peat. The calculation was made in the integrated botanical information system IBIS 7.2. Measurements of spectral characteristics were made by a UV/Visible Spectrophotometer T8DCS (PERSEE, China) at wavelengths of 250, 254, 365, 400 and 600 nm. In the UV-Win program, a baseline determining zero light absorption was constructed in relation to deionized water. The pH of peat was measured potentiometrically (HANNA Instruments, Edge, USA) in a suspension of a peat sample. The data analysis was performed in R, utilizing cluster analysis and correlation testing. The average concentration of organic carbon in peat is 50%, and the average reserve of organic carbon in a peat deposit is 205 ± 21.73 kg/m2. In the stratigraphic profile of the peat deposit, a layer of eutrophic peat is identified and further replaced by mesotrophic, and then by oligotrophic peat, which is characterized by the predominance of sphagnum mosses (Sph. balticum, Sph. majus, Sph. divinum and Sph. fuscum). It was found that a high moisture index (MI) corresponds to a low value of the richness and salinity index (RS) according to the Ramenskii scale. DOC concentrations have a negative correlation coefficient with MI and a positive correlation coefficient with the content of cotton grass, Scheuchzeria and dwarf shrubs in the stratigraphic profile. A decrease in DOC concentrations is observed with the predominance of Sph. balticum and Sph. divinum. The average DOC concentration in the peat deposit is 241.27 ± 52.48 mg/l. The SUVA254 index has maximum values of 0.55 ± 0.5 on average at depths of 100-200 cm. With an increase in the content of Sph. fuscum and Sph. balticum, the SUVA254 index decreases to 0.36. The bottom layer of all profiles is characterized by minimum SUVA254 values due to the presence of mineral soil impurities. The coefficient of the average molecular weight of organic compounds over the entire depth has an average value of 4.8 ± 0.8, and the average values of the humic substance ratio coefficient are 7.13 ± 3.2.

Post‐Annealing Induced Interdiffusion Layer Enhancing the Stability and Electrochemical Properties of LiCoO2 Thin Film Battery

Recently, thin film battery without binder is important power supplier for many low power microelectronic devices due to their compact size, flexibility for integration. We investigated the significance of the post‐annealing process in enhancing the stability of the electrodes in “thin film battery”. The LCO film annealed at 600°C for 4h exhibited the higher first cycle charge (discharge) capacity of 102.5 mAhg‐1 (80 mAhg‐1), initial coulombic efficiency (ICE) of 78.04 % as well as capacity retention of 59.37% at 0.2 C over 100 cycles as compared to the as‐deposited LCO films. The enhanced battery performances were attributed to the enhanced physical and chemical stability of the annealed film to endure the structural and composition evolutions. Specifically, an interfacial layer of Li‐Co‐Al‐O compound formed upon annealing, verified by elemental analysis along with transmission electron microscopy, resulting from the interdiffusion of Co and Al. The Li‐Co‐Al‐O compound demonstrates higher chemical bonding capability leading to higher stability performance and longer battery lifetime even unfavorable for electronic conduction. Apparently, our work inspires the next‐generation high‐power battery systems to reflect the trade‐off study of electrochemical and stability of batteries.

Tuning 2,3-Bis(arylimino)butane-nickel Precatalysts for High-Molecular-Weight Polyethylene Elastomers

The catalytic performance of α-diiminonickel complexes is highly sensitive to structural modifications in their ligand frameworks. In this study, a series of unsymmetrical 2,3-bis(arylimino)butane-nickel complexes featuring ortho-2,6-dibenzhydryl groups as sterically demanding motifs and para-methyl groups as electron-donating enhancers were proposed and synthesized. These nickel complexes were thoroughly characterized using FTIR, elemental analysis, and single-crystal X-ray diffraction (for Ni4 and Ni5), revealing deviations from ideal tetrahedral geometry. Upon activation with Et2AlCl, these complexes demonstrated exceptional ethylene polymerization activity, achieving a remarkable value of 13.67 × 106 g PE mol−1 (Ni) h−1 at 20 °C. Notably, even at 80 °C, the nickel complexes maintained a high activity of 1.97 × 106 g PE mol−1 (Ni) h−1, showcasing superiority compared to previously reported unsymmetrical 2,3-bis(arylimino)butane-nickel complexes. The resulting polyethylenes exhibited ultra-high molecular weights (Mw: 3.33–19.47 × 105 g mol−1) and tunable branching densities (84–217/1000C), which were effectively controlled by polymerization temperature. Moreover, the mechanical properties of the polyethylenes, including tensile strength (σb = 0.74–16.83 MPa), elongation at break (εb = 271–475%), and elastic recovery (SR = 42–74%), were finely tailored by optimizing molecular weight, crystallinity, and branching degree. The prepared polyethylenes displayed outstanding elastic recovery, a hallmark of high-performance thermoplastic elastomers, making them promising candidates for advanced material applications.

Synthesis and Characterization of Octahedral Ni(II) and Cu(II) Complexes With Imidazole‐Based Ligands: Structural, DFT, and Molecular Docking, Enhanced Antimicrobial, and Anti‐Inflammatory Activity

ABSTRACTThis study presents the synthesis, characterization, and biological evaluation of novel Ni(II) and Cu(II) metal complexes formed with imidazoleacetic acid (IA) and an imidazole‐based ligand (IM). The novelty of this work lies in the development of these metal–ligand frameworks and their enhanced biological properties, which surpass those of their free ligands. A comprehensive suite of analytical techniques, including elemental analysis, IR spectroscopy, magnetic moment measurements, electronic spectra, mass spectrometry, thermal analysis, and DFT calculations, confirmed the successful formation of the NiIAIM and CuIAIM complexes with a 1:1:1 (M:IA:IM) stoichiometry and octahedral geometry. DFT calculations revealed that metal coordination effectively lowered the energy gap, increasing the complexes softness and reactivity, thereby enhancing their predicted biological activity. Antimicrobial studies demonstrated that both NiIAIM and CuIAIM complexes exhibited superior antibacterial potency against Gram‐positive and Gram‐negative bacteria compared to their free ligands, with activity comparable to the standard antibiotic Chloramphenicol. Furthermore, both complexes showed significant antifungal efficacy against Candida albicans and Aspergillus niger, again outperforming the uncoordinated ligands. Minimum inhibition concentration (MIC) values further validate their potent antimicrobial effects. Additionally, the complexes displayed promising anti‐inflammatory activity, with the CuIAIM complex demonstrating the highest potency, approaching the efficacy of standard drugs based on IC50 values. Molecular docking studies against DNA gyrase B confirmed the CuIAIM complex as the most potent candidate, showing strong binding affinity through multiple hydrogen bonds with key amino acid residues, highlighting its potential antibacterial mechanism. In conclusion, the synthesized NiIAIM and CuIAIM complexes represent promising new antimicrobial and anti‐inflammatory agents, with significantly enhanced biological activity compared to their free ligands. These findings pave the way for further exploration of metal‐based therapeutics in combating infectious diseases and inflammation.

Elemental and isotopic analyses of individual nanoparticles using singleparticle inductively coupled plasma mass spectrometry.

Sensitive and rapid technique for elemental analysis of individual nanoparticles is increasingly desired in various research fields such as geochemical, environmental, clinical, and biochemical sciences. Among the techniques, single particle inductively coupled plasma mass spectrometry (spICP-MS) becomes one of the principal choices for the analytical method because of both the simple sample preparation and high analytical throughput, realizing the statistical treatments of the resulting data obtained from large numbers of particles. The analytical capability of the spICP-MS is further improved by the combination of ICP ion source with various types of mass spectrometers including quadrupole-type instrument, multiple collector system setup equipped on magnetic sector, or superfast mass scanning data acquisition utilizing timeofflight-type mass spectrometers. In this article, both the principles and applications of size, elemental, and isotopic analysis of nanoparticles using spICP-MS are critically reviewed.

Silica-Immobilized Pd-Amine Catalysts for Suzuki-Miyaura Coupling with Catalytic Amounts of Base.

Suzuki-Miyaura coupling is a robust method for constructing C-C bonds. Typically, stoichiometric amounts of a base are required. However, high pH conditions can lead to the protodeboronation of several substrates and generate stoichiometric waste salt from the additive base. Here, we present a Pd-amine co-immobilized catalyst enabling SMC with a catalytic amount of base; the amount of cross-coupling product was 18 times higher than that of co-immobilized amines. Furthermore, the use of a co-immobilized amine with a hydrophobic alkyl chain and a water-based solvent effectively removed acid byproducts from the Pd active species on the support surface, resulting in a high coupling product yield. The immobilized catalyst was characterized by elemental analysis, solid-state NMR, and X-ray absorption fine structure spectroscopy. Additionally, X-ray photoelectron spectroscopy, powder X-ray diffractometry, and transmission electron microscopy measurements revealed the in situ formation of Pd nanoparticles as the active species. Crucially, this system facilitates reactions even in the presence of aryl halides with acidic substituents.

Advanced biopolymer films for sustainable applications: Integrating Fe₃O₄ and ZnO nanoparticles into pea protein isolate-alginate matrices.

Advanced biopolymer films for sustainable applications: Integrating Fe₃O₄ and ZnO nanoparticles into pea protein isolate-alginate matrices.

Synthesis, crystal structural description, DNA binding, molecular docking, and anticancer evaluation of the novel platinum(IV) supramolecular complex

A novel platinum(IV) supramolecular complex; [PtCl2(2,2′-bipy)2](PtCl6) was synthesized in aqueous acetonitrile solution at ambient temperature with constant stirring. The structure was confirmed by elemental analysis, FT-IR, UV–vis, NMR spectroscopy, and single-crystal X-ray diffraction, revealing a unique distorted octahedral geometry and a three-dimensional network stabilized by hydrogen bonding and π–π stacking. DNA binding studies, including electronic absorption titration and viscometry, indicated a groove binding mechanism with a binding constant (Kb) of 5.00 × 10⁶ M−1. Molecular docking with DNA (PDB ID: 1BNA) and cancer-related proteins (PDB codes: 3ig7, 3eqm, 4fm9) supports these interactions, while in vitro anticancer assays demonstrated potent cytotoxicity with IC₅₀ values of 41.37 μM for HepG2, 47.62 μM for HCT116, and 73.90 μM for MDA-MB-231 cells, outperforming cisplatin in selectivity. This study not only advances our understanding of structure–activity relationships in platinum-based complexes but also highlights the potential of this complex as a promising candidate for developing more effective and less toxic anticancer agents.

Operando Measurement of Transition Metal Deposition in a NMC Li-Ion Battery Using Laboratory Confocal Micro-X-ray Fluorescence Spectroscopy.

The degradation of batteries has very different causes depending on the material and operation modes. However, most of these causes are associated with changes in one or more interfaces, in particular through depositions and their potential chemical changes under operating conditions. Over the last decade operando investigations have therefore become increasingly state-of-the-art, elemental analysis of full cell systems, though, is still missing due to a lack of depth resolved methods. Using laboratory confocal micro-X-ray fluorescence spectroscopy the analysis of a Li-ion battery coin cell during 10600 cycles are presented. It is shown that the confocal setup enables to differentiate between the nickel-manganese-cobalt-oxide (NMC) cathode with high levels of transition metal concentration and a possible deposition of traces of Mn, Ni, Co in the underlying layers. This allows for spatially resolved insights in operando without changing the layer stack, nor electrode area. This paper is the first to demonstrate the non-destructive and quantitative elemental analysis of battery interfaces under operating conditions. This quantitative analysis is the prerequisite for the determination of absolute transport and conversion rates, without which the transition from empirical research to a focused development of batteries will not succeed.

Interplay between Structure and Conduction mechanism of Piperazinium Functionalized Poly[ethylene pyrrole/ethylene ketone/propylene ketone] Anion Conducting Membranes.

Anion exchange membranes (AEMs) have been proposed as potential alternatives to proton exchange membranes in electrochemical energy conversion and storage devices.Herein, we report the synthesis of a series of AEM based on random piperazinium-methyl N-substituted poly[ethylene pyrrole/ethylene ketone/propylene ketone] (P-FPKK) and their structural characterization together with the elucidation of the ion conduction mechanism. Differentcopolymers are prepared by a Paal-Knorr reaction of a poly(ethylene ketone/propylene ketone)copolymer precursor with 1-(2-aminoethyl) piperazine, modulating the molar ratios amine/(1,4-diketonic repeat units of copolymer) from ¼ to 3. The composition and structure of resulting membranes are investigated by elemental analysis, ATR-FTIR,NMR andXRD. The degree of functionalization,f, plays a crucial role in controlling the thermal, morphological, and electrochemical properties of the P-FPKKf(I)g and P-FPKKf(OH)gmembranes. The P-FPKK0.49(OH)g ionomer displays an ionic conductivity of 11.3 mScm-1at 60°C. After alkaline aging (1M KOH at 60°C for 336 hours), it retains its structural integrity and 25% of its initial ionic conductivity value, suggesting them as possible candidates for testing in alkaline energy conversion and storage devices. Furthermore, the Broadband Electrical Spectroscopy studiesreveal that the long-range charge migration processes are modulated by the segmental motion of the backbone chains of the copolymer matrix.

Design, spectroscopic analysis, DFT calculations, adsorption evaluation, molecular docking, comprehensive in silico and in vitro bioactivity studies of thiocarbohydrazide grafted dialdehyde cellulose nanobiosorbent

Heavy metals have attracted considerable attention lately because of their widespread occurrence in aquatic environments and potential biological toxicity to animals and human. The current investigation focused on synthesizing the DAC@TCH nanobiosorbent by coupling dialdehyde cellulose with thiocarbohydrazide ligand. Subsequent characterization of DAC@TCH was carried out utilizing various analytical methods such as elemental analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR), and thermogravimetric analysis (TGA and DTA). DFT calculations were utilized to verify the molecular structure, analysis of frontier molecular orbitals (FMOs), molecular electrostatic potential (MEP) and reactivity descriptor for all phases. In vitro experiments were conducted to evaluate the biological properties of the DAC@TCH nanobiosorbent. These findings revealed that the synthesized DAC@TCH nanobiosorbent has been observed to show effective antibacterial IZD value against E. Coli (28 mm) which is superior to the efficacy of standard drug amoxicillin used (5 mm). Furthermore, in silico antibacterial activities (molecular docking) of the DAC@TCH have indicated this to exhibit excellent efficacy with docking score of (−7.4237 kcal/mol) and (−7.1325 kcal/mol) for S. aureus and, E. coli, respectively. Meanwhile the binding energies (best docking scores) in kcal/mol for Amoxicillin are (−5.8090) and (−6.7442) for S. aureus and, E. coli, respectively. Drug-likeness rules like Lipinski’s, Veber’s and Egan’s were considered for a more comprehensive evaluation. The prepared DAC@TCH nanobiosorbent was investigated for its potential to adsorb metal ions (Ag+, Hg2+, and Cu2+) from diverse water samples. Optimal conditions including pH, temperature, DAC@TCH dosage, oscillation time, initial metal ion concentration, and interference from other ions were explored. The adsorption of Hg2+, Cu2+, and Ag+ ions by DAC@TCH followed pseudo-second-order kinetics and Langmuir isothermal model, achieving maximum adsorption capacities of 196 mg/g for Ag+, 190 mg/g for Hg2+, and 73 mg/g for Cu2+. The adsorption process was determined to be exothermic and spontaneous across varying temperatures. Additionally, over 95% of adsorbed metal ions were effectively desorbed using thiourea (5%) and 0.3 M HNO3 elution mixture. DAC@TCH nanobiosorbent demonstrated excellent reusability, retaining its adsorption capacity through five cycles without degradation. The study highlights the potential of DAC@TCH for efficient recovery of heavy metals from different water sources, considering its application versatility, reusability, and minimal interference. Furthermore, the plausible mechanism of Ag+, Hg2+, and Cu2+ adsorption onto DAC@TCH bionanosorbent is elucidated.

Characterization of Cupuaçu (Theobroma grandiflorum) Waste for Substrate in Seedling Production

Cupuaçu (Theobroma grandiflorum (Willd. ex Spreng.) K. Schum.), a fruit native to the Amazon, is widely used in the food industry. However, it generates large amounts of shell and seed residues after processing, which are generally discarded inappropriately. We characterized cupuaçu residues to determine their potential as substrates for seedling production. Shells and fruit seeds were collected from a rural community in the municipality of Belterra, Brazil. The residues were weighed, dried, and crushed for chemical (macro and micronutrients, elemental analysis, and ash content) and physical (density and porosity) analyses. Different proportions of each residue (9:1, 3:1, 2:1, 1:1, and 0:1) were used, and soil alone was used as the control. The chemical analysis of the plant material showed that cupuaçu seed residues had higher concentrations of macro- and micronutrients among the analyzed elements when compared to the fruit shell residues. The macronutrient concentrations (P, K, Ca, and Mg) were, respectively, 5, 1.3, 2.3, and 5.6 times higher than those in the shell residues. Compared with the soil sample, the concentrations of the macronutrients (P, K, Ca, and Mg) in the shell residues were, respectively, 600, 162, 1283, and 12.35 times higher. Analysis of variance and comparison of treatment means were performed using Tukey’s test (p ≤ 0.05). Chemical analysis showed that cupuaçu seed and shell residues had higher concentrations of macro- and micronutrients than soil. All proportions tested with residues had lower densities and greater porosities than soil. The cupuaçu residues showed desirable chemical and physical characteristics for their use as substrate in seedling production.

Particulate matter in ambient air (Krk island, Croatia): elemental analysis, sources and microplastics.

Particulate matter in ambient air (Krk island, Croatia): elemental analysis, sources and microplastics.

One Pot Multicomponent Synthesis of Amino Pyrazole Promoted by Imidazole and Bioevluation

In the present study and followed by conventional method, an efficient and design synthesis a novel series of 5-Amino-1,3-diphenyl-1H-pyrazole-4-carbonitrile derivatives. These derivatives can be obtained by Phenyl hydrazine, aromatic aldehydes, and malononitrile in presence of base catalyst Imidazole in ethanol as a solvent at reflux. All the newly obtained derivatives were evaluated by the advanced spectroscopic analysis such as 1HNMR, 13CNMR and LCMS and structural determination of titled analogous were calculated by elemental analysis. In addition to the newly synthesised compounds were examined by their anti-microbial activity KEYWORDS: Phenyl hydrazine, aromatic aldehydes, and malononitrile, 5-Amino-1,3-diphenyl-1H-pyrazole-4-carbonitrile , imidazole , anti-microbial activity

Fluorine-Substituted Rhenium(I) Metallocycle: A New Class of Potent Anticancer Agent.

Fluorine and nonfluorine substituted rhenium(I) metallocycles, fac-[{Re(CO)3}2(μ-SO4)(L1)2] (C1) and fac-[{Re(CO)3}2(μ-SO4)(L2)2] (C2), respectively, were synthesized using Re2(CO)10, sodium bisulfite, fluorobenzimidazolyl/benzimidazolyl-based ditopic nitrogen-donor ligands (L1/L2), and toluene-acetone via coordination-driven one-pot solvothermal approach. The metallocycles were characterized using elemental analysis, ESI-TOF-MS, ATR-IR, NMR, and PXRD methods. The molecular structures of C1·9(DMSO), C1·(toluene)(acetone), and C2·(toluene) were determined using SCXRD analysis. The in vitro cytotoxicity study of C1 and C2 was performed against cervical (HeLa) and skin (B16) cancer cells. Murine fibroblast (L929) and mouse myoblast (C2C12) cells were used as noncarcinogenic model cell lines for biocompatibility determination. The metallocycles exhibited potent anticancer activity against both cancer cell lines, showing greater efficacy than the commonly used cisplatin. Moreover, fluorine-substituted C1 metallocycle exhibited significantly higher anticancer activity than nonfluorinated C2 metallocycle, indicating a fluorine effect. Further, in-depth studies of C1 on HeLa cells showed elevated intracellular ROS generation, disruption of mitochondrial membrane potential, and antiproliferative properties. The in vitro studies also revealed its ability to bind with DNA and induce changes in cellular morphology, thus leading to DNA damage and cancer cell death by apoptosis. Molecular docking studies of the metallocycles with B-DNA macromolecule revealed the binding sites, binding affinity, and type of noncovalent interactions.

Understanding Oxygen Concentrator Failures in Low Resource Settings: The Role of Dust and Humidity

Oxygen concentrators (OCs) are essential medical devices providing oxygen in various settings, especially low-resource settings (LRSs). Despite their adaptability and cost-effectiveness, challenges arise in such environments due to factors like dust, temperature, and humidity, leading to premature OC failure. While efforts have been made to address these issues, understanding the primary contributing factor remains unclear. This study aims to shed light on this matter through the analysis of exhausted zeolite samples from Uganda, Ethiopia, and South Africa alongside a commercial virgin sample. The samples were comprehensively characterized through powder X-ray diffraction (PXRD) analysis, wavelength dispersive X-ray fluorescence (WDXRF) elemental analysis, Brunauer–Emmett–Teller (BET) surface analysis, and thermo-gravimetric analysis (TGA) coupled with mass spectrometry (MS). The characterization results confirmed a low silicon X-type framework (FAU-LSX) for all the samples. The maximum mass loss during TGA tests occurred at 130–160 °C, suggesting that water is the main component released from the zeolites. This was confirmed by MS analysis, which revealed the predominance of water in all the sample matrices. A correlation was found between OC efficiency and the amount of water adsorbed by the zeolites, proving that humidity has a key role in causing OC malfunctioning. No evidence for the presence of dust as a contaminant in the zeolites was found by the absence of the expected chemical elements in WDXRF. Since the outcomes of the study are independent of the geographical origin of the zeolites, its findings provide general guidance for engineers to modify OCs and prevent zeolite moisture poisoning.

The Significance of Herbicide–Humin Interactions in Sustainable Agroecosystems

Humin, as the most stable fraction in soil organic matter, determines possibility of sustainable environmental development by influencing, among other things, the binding and migration of different chemicals in soil. The aim of this paper was to determine changes in the properties of humins after interaction with three selected active substances of herbicides differing in structure and chemical properties (pendimethalin, metazachlor, and flufenacet) and two different commercial products. In accordance with OECD 106 guidelines, humins isolated from eight different soils were saturated with herbicide compounds under study. As humin is a non-hydrolyzable organic carbon fraction, solid state research techniques (elemental analysis, NMR, FTIR, EPR, and UV-Vis) were applied. The results clearly showed that the interaction between humin and herbicides increases the concentration of oxygen-containing groups and the internal oxidation (ω) in humin. For all investigated humins, a reduction in radical concentration was observed. Radicals in humins were not completely quenched; a certain concentration of radicals with unchanged structure always remained in the samples. Other spectroscopic analyses showed no significant changes in the structure of pesticide-saturated and non-saturated humins. This suggests that sorption of the studied compounds occurs on the humins only as a result of the interaction of physical forces on the surface of the studied organic matter fraction. Thus, interaction with the studied herbicides occurs as a surface phenomenon, and the inner core remains protected by the condensed structure and/or strong binding to the clay minerals.

Green Pseudo-seven Component Synthesis of Tris-cyclohexylamino-oxo-benzene- 1,3,5-tricarboxylates via Passerini Reaction under Aqueous Conditions

In this study, a simple, mild, and environmentally friendly process was used for the pseudo-seven component reaction between readily available benzene-1,3,5- tricarboxylic acid, isocyano-cyclohexane, and various aldehydes. This rapid method produced the tris-cyclohexylamino-oxo-benzene-1,3,5-tricarboxylates in relatively acceptable and more reasonable reaction times (10-15 min) and high achievable efficiencies (85-95%) by employing a Passerini reaction. Water was used as an eco-friendly and low-cost solvent for the green synthesis of benzene tris-carboxamides. The reactions were carried out via a Passerini approach at 50ºC for relatively shorter reaction times. The antibacterial action of the synthetic tris-carboxamides was investigated, and some of them gave satisfactory and promising antibacterial results. Target tris-Passerini molecules recrystallized from 96% EtOH. The structures of the resulting molecules were evaluated and confirmed with the help of spectral data and elemental analyses.

Synthesis and Structural Elucidation of a Novel Hetero-Dodecametallic Yttrium-Sodium Complex Based on EDTA: Insights into f/s-Block Coordination Chemistry

Heterometallic f/s-block complexes are not plentiful but play pivotal roles in understanding metal synergy in materials science and catalysis. Reaction of Y(NO3)3.6H2O with EDTANa2.2H2O (ethylenediaminetetraacetic acid, disodium salt dihydrate) gives the dodecanuclear {Y4Na8(L)4(OH)2(NO3)2(H2O)16} (1). Complex (1) is characterized by elemental analyses, IR and conductance measurement. The structure of (1) was elucidated by X-ray diffraction analysis. The compound crystallizes in the monoclinic space group P21/c with the following parameters: a = 24.81289 (15) Å, b = 15.63590 (8) Å, c = 19.68764 (14) Å, = 106.6623 (7)°, V = 7317.53 (8) Å3, Z= 4, R1 = 0.041, wR2 = 0.117. The asymmetric unit of the compound contains four tetradeprotonated (L4-) EDTA molecules, four octacoordinated yttrium ions, three pentacoordinated sodium ions, five hexacoordinated sodium ions, two chelating nitrate groups, two hydroxy groups acting in \(\mu\)2-mode, seven coordinated water molecules acting in \(\eta\)1-mode and nine coordinated water molecules acting in \(\mu\)2-mode. Each of the YIII cations is coordinated by one fully deprotonated EDTA which link also four NaI cations. Each of the NO3- anions bridge two YIII ions, while each of the two hydroxy groups bride one YIII cation and one NaI cation. The environment around the octacoordinated YIII cations are best described as a square antiprisms. The environments around the pentacoordinated NaI ions are best described as a square pyramidal geometries, while the hexacoordinated NaI ions exhibit octahedral environments. The molecule features a typical 3D hydrogen-bonded network with diverse coordination geometries (square antiprismatic Y³⁺, square pyramidal/octahedral Na⁺).

Molecular characteristics of emerging perfluoroalkyl and polyfluoroalkyl substances (PFAS) and dissolved organic matter (DOM) in surface waters around fluorine-related industries in a Chinese Megacity.

Molecular characteristics of emerging perfluoroalkyl and polyfluoroalkyl substances (PFAS) and dissolved organic matter (DOM) in surface waters around fluorine-related industries in a Chinese Megacity.