X-ray Powder Diffraction Analysis Research Articles

{SeO2(OH)} Bridging Lanthanide-Containing Antimono-Seleno-Tungstates.

A series of new trigonal pyramidal {SeO2(OH)} bridging lanthanide-containing antimono-seleno-tungstates [H2N(CH3)2]8Na8Cs4H9[Ln2SeW4O11(OH)(H2O)4(SbW9O33)(SeW9O33)(Se1/2Sb1/2W9O33)]2·32H2O [Ln = Tb (1), Dy (2), Ho (3), Er (4)] have been prepared by the synthetic strategy of simultaneously using the antimonotungstate precursor and simple material in an acidic aqueous solution and structurally characterized by single-crystal X-ray diffraction, powder X-ray diffraction, IR spectrometry, and thermogravimetric analysis. Their molecular structures contain an unprecedented hexameric polyoxoanion [Ln2SeW4O11(OH)(H2O)4(SbW9O33)(SeW9O33)(Se1/2Sb1/2W9O33)]229- constituted by two equivalent trimeric subunits Ln2W4O9(H2O)4(SbW9O33)(SeW9O33)(Se1/2Sb1/2W9O33) bridged via two μ2-{SeO2(OH)} linkers. Furthermore, the catalytic oxidation of various aromatic sulfides and sulfur mustard simulant 2-chloroethyl ethyl sulfide (CEES) by compound 3 as the heterogeneous catalyst has been investigated, exhibiting high conversion and selectivity as well as good stability and recyclability.

CO2-Based Stable Porous Metal-Organic Frameworks for CO2 Utilization.

The transformation of carbon dioxide (CO2) into functional materials has garnered considerable worldwide interest. Metal-organic frameworks (MOFs), as a distinctive class of materials, have made great contributions to CO2 capture and conversion. However, facile conversion of CO2 to stable porous MOFs for CO2 utilization remains unexplored. Herein, we present a facile methodology of using CO2 to synthesize stable zirconium-based MOFs. Two zirconium-based MOFs CO2-Zr-DEP and CO2-Zr-DEDP with face-centered cubic topology were obtained via a sequential desilylation-carboxylation-coordination reaction. The MOFs exhibit excellent crystallinity, as verified through powder X-ray diffraction and high-resolution transmission electron microscopy analyses. They also have notable porosity with high surface area (SBET up to 3688 m2 g-1) and good CO2 adsorption capacity (up to 12.5 wt %). The resulting MOFs have abundant alkyne functional moieties, confirmed through 13C cross-polarization/magic angle spinning nuclear magnetic resonance and Fourier transform infrared spectra. Leveraging the catalytic prowess of Ag(I) in diverse CO2-involved reactions, we incorporated Ag(I) into zirconium-based MOFs, capitalizing on their interactions with carbon-carbon π-bonds of alkynes, thereby forming a heterogeneous catalyst. This catalyst demonstrates outstanding efficiency in catalyzing the conversion of CO2 and propargylic alcohols into cyclic carbonates, achieving >99% yield at room temperature and atmospheric pressure conditions. Thus, this work provides a dual CO2 utilization strategy, encompassing the synthesis of CO2-based MOFs (20-24 wt % from CO2) and their subsequent application in CO2 capture and conversion processes. This approach significantly enhances overall CO2 utilization.

Preparation of single crystals of palmatine-sulfophenyl acids pharmaceutical salts by substituting Cl− in palmatine chloride to improve hygroscopic stability and antibacterial activity of palmatine and to preserve its solubility

To enhance the hygroscopic stability of palmatine chloride (PMTCl) while maintaining its solubility, several unexplored pharmaceutical salts of palmatine (PMT) were synthesised using benzenesulfonic acid (PMT-BSA), p-toluenesulfonic acid (PMT-PTSA), and aminobenzenesulfonic acid (PMT-SUL). These novel salts were thoroughly characterized using techniques such as single-crystal X-ray diffraction, powder X-ray diffraction (PXRD), infrared spectroscopy (IR), and Hirshfeld surface analysis to determine their structural properties. Surprisingly, it was discovered that these salts exhibited improved antibacterial activity in addition to their enhanced hygroscopic stability. As anticipated, all three pharmaceutical salts demonstrated improved hygroscopic stability. This improvement might be attributed, to some extent, to the introduction of safe, stable, and less electronegative anions (BSA, PTSA, and SUL) to replace the more electronegative chloride (Cl−) in PMTCl. The replacement of Cl− hindered the binding of the pharmaceutical with external water molecules, thus increasing its resistance to moisture. Moreover, the interaction between PMT and the anions from the benzenesulfonic acid group via hydrogen bonding might have played a role in the improved hygroscopic stability. The crystal structure formed by the PMT molecules exhibited long-range order, while the benzenesulfonic acid anions cleverly avoided potential binding sites for water molecules. Additionally, the antibacterial activities of all three pharmaceutical salts were enhanced. This improvement can be attributed to the alteration of electron cloud density (ρe) in the isoquinoline group of PMT upon the introduction of benzenesulfonate anions to form the pharmaceutical salts. This hypothesis was supported by analyzing the molecular electrostatic potential, electron cloud density, and Hirshfeld surface. The successful outcome of this study suggests that modifying the ρe of the isoquinoline group in protoberberines through the introduction of benzenesulfonic acid anions to form pharmaceutical salts can potentially alter their physicochemical properties and biological activities. This finding paves the way for future research on improving the physicochemical properties of protoberberines-based pharmaceuticals.

Coordination Polymer Based on a Triangular Carboxylate Core {Fe(μ3-O)(μ-O2CR)6} and an Aliphatic Diamine.

Interaction of the pre-organized complex of iron(II) trimethylacetate and 1,10-phenanthroline (phen) [Fe2(piv)4(phen)2] (1) (piv = (Me)3CCO2-)) with 1,6-diaminohexane (dahx) in anhydrous acetonitrile yielded a 1D coordination polymer [Fe3O(piv)6(dahx)1.5]n (2) and an organic salt of pivalic acid (H2dahx)(piv)2 (3). The structure of the obtained compounds was determined by single-crystal X-ray diffraction analysis. The phase purity of the complexes was determined by powder X-ray diffraction analysis. According to the single-crystal X-ray analysis, coordination polymer 2 is formed due to the binding of a triangular carboxylate core {Fe3(μ3-O)(μ-piv)6} with an aliphatic diamine ligand. Thermal behavior was investigated for compounds 1 and 2 in an argon atmosphere.

Investigations on Growth, Characterization, NCI-RDG, AIM, Molecular Docking and In-Silico ADME Properties of 1,2-Benzene Dicarboxylic Acid Anhydride

Superior single crystal of 1,2-benzene dicarboxylic acid anhydride additionally called Phthalic anhydride (PAN) was developed via solution growth at low temperatures. Single crystal X-ray diffraction investigation revealed the crystal system and unit cell characteristics. The phase stability and crystalline nature were uncovered by powder X-ray diffraction analysis. FT-IR examination was done for the titular material so as to survey the various functional groups. With the use of the VEDA program's relevant resources, vibrational assignments have been made on the concept of Potential Energy Distribution (PED). Density Functional Theory (DFT) was employed to smooth out the molecular structure of PAN and was additionally utilized to consider FT-IR spectrum at molecular level.  Non covalent interactions reduced density gradient (NCI-RDG) analysis has been used for the prediction of the weak interaction in the actual space in terms of the electron density along with its derivatives for PAN. Atoms in Molecules (AIM) analysis was carried for out for PAN. The docking research of the small molecule (PAN) with target protein confirmed that this is a great molecule which docks nicely with numerous targets associated with Hypoxia Inducible Factor 1-α. The absorption, distribution, metabolism, excretion (ADME) characteristics have been calculated with the assist of online server preADMET.

Solid state synthesis, structural, DFT and spectroscopic analysis of EuAl3(BO3)4

Huntite-like borates are versatile and promising materials with wide range of applications in frequency conversion, UV light generation, lighting, displays, quantum information storage, and more, demonstrated by their various properties and uses in scientific research. In this work, EuAl3(BO3)4 powder was prepared through multi-stage solid-state reaction method using high-purity starting reagents: Eu2O3, Al2O3 and H3BO3, considering a 20 wt% excess of H3BO3 to compensate for B2O3 volatilization. Obtained samples undergo several treatments at varying temperatures and their phase purity is subsequently verified through powder X-ray diffraction analysis. The scanning electron microscopy reveals that resulting EuAl3(BO3)4 powder consists of granules exhibiting irregular morphologies with dimensions of 0.5–8 μm. The electronic band structure of EuAl3(BO3)4, calculated using the GGA PBE method, reveals f-states of Eu near 4 eV. These states do not produce emphasized peaks on simulated absorbance spectra. Using of DFT + U for the f-states of Eu pushed up f-bands above 6 eV and the charge transfer from p-O to d-Eu was obtained (Egdirect = 5.63 eV, Egindirect = 5.37 eV using Ueff = 4 eV). The variation of Ueff has a weak influence on the position of the bottom of the conduction band. The experimental bandgaps of EuAl3(BO3)4 crystalline powder, both direct and indirect, are found to be 3.96 and 3.67 eV, correspondingly. These values are lower than theoretical values what is associated with limitations of DFT calculations involving f electrons. The Raman spectrum of EuAl3(BO3)4 powder is discussed, detailing the contributions of different ions to specific spectral bands. Investigation of high-resolution luminescence spectra shows the possibility to estimate the content of defects by the testing the violation of the prohibition of ultranarrow 5D0 → 7F0 line that is forbidden in the ideal crystalline structure of trigonal EuAl3(BO3)4.

Effect of Processing Routes on Physical and Mechanical Properties of Advanced Cermet System

The present research focuses on the effects of different processing routes on the physical and mechanical properties of nano Ti(CN)-based cermets with metallic binders. Tungsten carbide (WC) is added as a secondary carbide and Ni-Co is added as a metallic binder to nano Ti(CN)-based cermet processed via conventional and spark plasma sintering (SPS). A systematic comparison of the composition and sintering conditions for different cermets’ systems was carried out to design novel composition and sintering conditions. Nano TiCN powder was prepared by 30 h of ball milling. The highest density of >98.5% was achieved for the SPS-processed cermets sintered at 1200 °C and 1250 °C for 3 min at 60 MPa of pressure in comparison to the conventionally sintered cermets at 1400 °C for 1 h with a two-stage compaction process—uniaxially at 150 MPa and isostatically at 300 MPa of pressure. Comparative X-ray diffraction (XRD) analysis of the milled powders at different time intervals was performed to understand the characteristics of the as-received and milled powders. Peak broadening was observed after 5 h of ball milling, and it increased to 30 hr. Also, peak broadening and a refined carbide size was observed in the XRD and scanning electron microscope (SEM) micrographs of the SPS-processed cermet. Transmission electron microscope (TEM) analysis of the milled powder showed that its internal structure had a regular periodic arrangement of planes. SEM base scattered electron (BSE) images of all the cermets primarily showed three major microstructural phases of the core–rim–binder with black, grey, and white contrast, respectively. With the present sintering conditions, a high hardness of ~16 GPa and a fracture toughness of ~9 MPa m1/2 were obtained for SPS-processed cermets sintered at higher temperatures.

Surface oxygen vacancy vs oxygen storage capacity in cubic ceria based nanocatalysts for low temperature catalytic combustion of fuels

A series of praseodymium (Pr) doped cubic ceria nanoparticles (CeO2 NPs) with different ratio of cerium (Ce) and ‘Pr’ was synthesized by hydrothermal method. Manganese (‘Mn’) doped cubic CeO2 NPs with 10:90 ratio of Mn:Ce and undoped cubic CeO2 NPs have also been synthesized. The crystalline structure of the synthesized nanomaterials has been studied by powder X-Ray diffraction (XRD) and Rietveld analysis. In the Raman spectrum, the intensity of F2g signal at 450–460 cm−1 decreased while the intensity of extrinsic vacancy at 570–580cm−1 increased by doping with ‘Pr’ or ‘Mn’ in cubic CeO2 nanocrystals. X-ray photoelectron spectroscopy (XPS) results showed that surface oxygen vacancy of cubic CeO2 NPs increased by doping with 25 % of ‘Pr’. The ‘Pr’ doped CeO2 NPs (Pr:Ce = 25:75) exhibited higher surface adsorption dynamic oxygen storage capacity (OSCDyn), while the ‘Mn’ doped cubic CeO2 NPs (Mn:Ce = 10:90) showed increased bulk lattice OSCDyn. The ‘Pr’ doped cubic CeO2 NPs (Pr:Ce = 25:75) exhibited better low temperature catalytic combustion activity, and their nanodispersion in mineral turpentine oil (MTO) added liquefied petroleum gas (LPG) exhibited better fuel efficiency with a flame temperature of 912 °C.

Transport properties of mechanochemically synthesized copper (I) selenide for potential applications in energy conversion and storage

This work studied the thermal stability, electrical, and thermoelectrical properties of copper(I) selenide, Cu2Se synthesized by high-energy milling in a planetary ball mill. The phase composition was investigated by X-ray powder diffraction analysis and scanning electron microscopy. The conversion of the precursors during mechanochemical synthesis and the stability of the product was monitored by thermal analysis. The dependence of electrical properties on the product porosity was observed. For the densification of Cu2Se, the method of spark plasma sintering was applied to prepare suitable samples for thermoelectric characterization. High-temperature thermoelectric properties of synthetic Cu2Se were compared to its natural analogue-mineral berzelianite in terms of its potential application in energy conversion. Based on the results a relatively high figure-of-merit, ZT parameter (~ 1.15, T = 770 K) was obtained for undoped Cu2Se, prepared by rapid mechanochemical reaction (5 min). Cyclic voltammetry measurements of Na/NaClO4/Cu2Se cell implied that mechanochemically synthesized Cu2Se could be used as a promising intercalation electrode for sodium-ion batteries.

Determination of solubility of sildenafil citrate in propylene glycol + 2-propanol and N-methyl pyrrolidone + water: Comparing solubilization power of aqueous or non-aqueous mixtures

For identifying the solubilization power of aqueous and non-aqueous solvent mixtures for sildenafil citrate (SLC), its solubility was determined in four mono-solvents of propylene glycol, 2-propanol, N-methyl pyrrolidone and water along with the binary solvent mixtures of propylene glycol + 2-propanol and N-methyl pyrrolidone + water at 293.2 to 313.2 K and at pressure of 85 kPa. Among the neat organic solvents and also water, N-methyl pyrrolidone presented a high solubilization power for SLC (8.66 × 10-2 at 313.2 K) and its aqueous binary mixtures had also a more ability to solubilize the drug in compared with the binary (propylene glycol + 2-propanol) mixtures (with the highest value of 4.96 × 10–4 at 313.2 K). Besides, increasing the solubility of SLC with raising temperature illustrated that its dissolution in the aforementioned mixtures was endothermic. The equilibrium solid phase crystal of SLC was also characterized with X-ray powder diffraction analysis to identify no polymorphic transformation, solvate formation or crystal transition during the whole solvent crystallization process. Moreover, the experimental mole fractions were modelled by used commonly cosolvency models and regressed the model parameters. The back-calculated mole fractions of SLC by cosolvency models shown a better agreement with the experimental data (overall mean percentage deviation (OMPD) ≤ 7.6 %) and Jouyban-Acree model as a function of temperature and solvent compositions had the best performance (MPD of 3.2 %). Furthermore, the solubility data sets of SLC in 7 binary solvent mixtures were collected from the literature and correlated with the Jouyban-Acree model and its derivates, the OMPDs for the back-computed solubility indicating the generally trained models, especially Jouyban-Acree-Abraham model (MPD of 24.2 %), had an acceptable ability in the prediction of SLC solubility and can be useful in the pharmaceutical industry. Finally, apparent thermodynamic properties of Gibbs free energy, standard enthalpy and entropy of the dissolution processes were also investigated.

Synthesis and growth of organic 2-ethylimidazolium hydrogen diglycolate single crystal for nonlinear optical applications

A single crystal of 2-Ethylimidazolium hydrogen diglycolate (DAEI) has been grown by slow evaporation solution (SEST) technique at 35 °C. The DAEI crystal belongs to a monoclinic crystal system with a P21/c space group. The Hirshfeld surface analysis determined the grown crystal has the highest intermolecular contribution for O..H interaction. The phase purity and various planes (hkl) of the DAEI crystal system were determined by powder X-ray diffraction analysis (PXRD). The functional groups and their different vibrations of DAEI crystal were identified by Fourier transform infrared analysis. The band gap energy value of the DAEI crystal is found to be 5.32 eV. Photoluminescence measurement reveals that the DAEI crystal has green emission. The material shows major weight losses of around 82.45 % in the temperature between 140 °C and 300 °C. The dielectric analyses were carried out for different frequencies (1Hz–1MHz) and different temperatures. The third-order nonlinear optical properties such as refractive index (n2), absorption coefficient (β) and susceptibility (χ(3)) were determined using the Z-scan technique using a He–Ne laser (λ = 632.8 nm).

CO2 Promoting Polymorphic Transformation of Clarithromycin: Polymorph Characterization, Pathway Design, and Mechanism Study

Carbon dioxide (CO2) has a wide range of uses such as food additives and raw materials for synthetic chemicals, while its application in the solid-state transformation of pharmaceutical crystals is rare. In this work, we report a case of using 1 atm CO2 as an accelerator to promote the polymorphic transformation of clarithromycin (CLA). Initially, crystal structures of Form 0′ and three solvates were successfully determined by single crystal X-ray diffraction (SCXRD) analysis for the first time and found to be isomorphous. Powder X-ray diffraction (PXRD) and thermal analysis indicated that the solvate desolvates and transforms into the structurally similar non-solvated Form 0′ at room temperature to ~50 °C. Form 0′ and Form II are monotropically related polymorphs with Form II being the most stable. Subsequently, the effect of CO2 on the transformation of CLA solvates to Form II was studied. The results show that CO2 can significantly facilitate the transformation of Form 0′ to Form II, despite no significant effect on the desolvation process. Finally, the molecular mechanism of CO2 promoting the polymorphic transformation was revealed by the combination of the measurement of adsorption capacity, theoretical calculations as well as crystal structure analysis. Based on the above results, a new pathway of preparing CLA Form II was designed: transform CLA solvates into Form 0′ in 1 atm air at 50 °C followed by the transformation of Form 0′ to Form II in 1 atm CO2 at 50 °C. This work provides a new idea for promoting the phase transformation of pharmaceutical crystals as well as a new scenario for the utilization of CO2.

Agate Mineralization in Paleoproterozoic Organic Carbon-Rich Sedimentary Rocks of the Onega Basin (NW Russia): Insights into Genesis

In this contribution, we present the results of mineralogical investigation of the agates in Paleoproterozoic organic carbon-rich sedimentary rocks within the Onega Basin (Fennoscandian shield, Russia) aimed at reconstructing the agate-forming processes. Optical and scanning electron microscopy, EDS microanalysis, thermal analysis, X-ray powder diffraction, Raman spectroscopy, and carbon isotope analysis were used for the study. Three main varieties of agates differing in morphology and texture were identified, including concentrically zoned nodules, fine-banded, and carbon-rich moss agates. Mineralogical evidence indicates the participation of hydrothermal fluids in agate formation. Concentrically zoned nodules could be formed due to the dissolution of carbonate concretions in the organic carbon-rich siltstones and their silicification as a result of late hydrothermal processes. Fine-banded vein agates occur in stockworks crosscutting organic carbon-rich rocks and are widely accompanied by sulfides, selenides, carbonates, sulfates, and iron oxides. Carbonaceous matter in moss agates is present as poorly ordered carbon and is characterized by a low δ13Corg value (−25.64‰), suggesting a biogenic origin. Raman spectroscopy data showed an elevated amount of moganite besides alpha quartz in the concentrically zoned nodules compared to other agate varieties, indicating different ages of the mineralization processes. We suggest that the revealed varieties of agates were formed at different stages of long-term hydrothermal processes occurring in the Onega Basin.

Structural, optical and theoretical studies of 2,4-dichlorobenzoic acid benzamide in nonlinear optical applications using Z-scan technique

New organic 2,4-dichlorobenzoic acid benzamide co-crystal (DCBB) was successfully grown using slow evaporation solution growth technique. The formation of new DCBBco-crystals was taken and their structure and crystallinity were analyzed by single crystal and powder X-ray diffraction analyses. It shows that DCBB material in monoclinic structure with centrosymmetric space group of P21/c. The different vibrations, chemical bonding and chemical configuration of the co-crystal was studied through FTIR, Raman and 1H NMR spectroscopy. Optical transmittance is the basic requirement for the nonlinear optical application with a lower cutoff wavelength of about 320 nm as well as optical band gap value Eg is 3.84 eV. Photoluminescence spectrum showing two emission peaks of 403 and 550 nm by means of an excitation wavelength of 290 nm. The compound's thermal stability was up to 125 °C was analyzed by the thermal analysis. Vickers's micro hardness test was used for evaluating mechanical properties of DCBB, and the results showed that the material was classified as soft category (n = 2.54). Nonlinear optical characteristics of the sample under pulsed laser stimulation by Q-switched Nd:YAG laser with 532 nm wavelength. The presence of reverse saturable absorption peak exhibits 2-photon absorption process was confirmed by varying its intensity shows saturation intensity IS), nonlinear absorption coefficient (β) under pulse laser excitation. The optical limiting threshold determined by three different intensities were found to be 3.02×1012 (W/m2), 2.85×1012 (W/m2) and 1.44×1012 (W/m2) respectively. Theoretical investigations like density functional theory using B3LYP to calculate as well as determining non-linear optical characteristics of the DCBB complex.

Molecularly Imprinted Drug Carrier for Lamotrigine-Design, Synthesis, and Characterization of Physicochemical Parameters.

This study presents the initial attempt at introducing a magnetic molecularly imprinted polymer (MIP) designed specifically for lamotrigine with the purpose of functioning as a drug carrier. First, the composition of the magnetic polymer underwent optimization based on bulk polymer adsorption studies and theoretical analyses. The magnetic MIP was synthesized from itaconic acid and ethylene glycol dimethacrylate exhibiting a drug loading capacity of 3.4 ± 0.9 μg g-1. Structural characterization was performed using powder X-ray diffraction analysis, vibrating sample magnetometry, and Fourier transform infrared spectroscopy. The resulting MIP demonstrated controlled drug released characteristics without a burst effect in the phospahe buffer saline at pH 5 and 8. These findings hold promise for the potential nasal administration of lamotrigine in future applications.

Tau-borides (Mnx{Ru,Os,Ir}1-x)23B6: X-ray single crystal and TEM data, physical properties

Investigation (electron microprobe and X-ray powder and single crystal diffraction analyses) of the phase relations in the Mn-rich corner (> 45 at% Mn) of the systems Mn-{Ru,Os,Ir}-B, prompted in all three systems a ternary compound with formula (Mnx{Ru,Os,Ir}1-x)23B6. For the systems Mn-Ru-B, Mn-Ir-B phase equilibria have been determined at 950°C (Ru), 900°C (Ir) revealing in both cases a small homogeneity region at constant B-content (Mn1-xRux)23B6 (0.29 < x < 0.37); (Mn1-xOsx)23B6 (0.33 < x < 0.37), as well as (Mn1-xIrx)23B6 (0.29 < x < 0.34). The crystal structure of the three compounds was determined from single crystal and X-ray powder intensity data analyses to be isotypic with the Cr23B6-type (so-called tau-phase, space group Fm3¯m, No. 225). In all cases Mn atoms fully occupy the 4a site (0,0,0) at the origin of the unit cell. For the 8c site (¼,¼,¼) we observed a random distribution of Mn1-x(PM)x with decreasing PM content (PM stands for a platinum group metal atom) going from Ru to Os and Ir, where Mn atoms fully occupy 8c. Whereas the remaining sites (48h, 32f) show various ratios of the two metal species, boron atoms fully occupy the centers (24e site) of the Archimedean metal atom antiprisms. A transmission electron microscopic study confirms the absence of superstructures related to these metal atom disorder, thus Mn and PM atoms randomly share their sites. The latter is well reflected in the behavior of the electrical resistivity of these compounds, which is dominated by disorder scattering. For (Mn0.6{Ru,Os}0.4)23B6, temperature dependent dc magnetization studies reveal distinct antiferromagnetic-like anomalies at TN ≅ 72 K and 114 K, respectively. Low field dc and ac magnetic susceptibility data of (Mn0.7Ir0.3)23B6 display a distinct ferromagnetic-like transition at TC = 280 K, consistent with a pronounced specific heat anomaly and a rather continuous temperature dependent evolution of magnetic anisotropy effects. Mechanical properties (hardness) characterize the tau phases among rather hard and brittle intermetallics (about 5–6 GPa).

Multi-responsive luminescent complex for Fe3+, Cr2O72− and CrO42− species in aqueous solution based on aromatic polycarboxylic acid and imidazole-containing ligand: synthesis, crystal structure and selective detection

One Cadmium(II)-based complex, [Cd(LBIX)(HEA)]n (1), was synthesized using 4,4′-bis((1H-imidazol-1-yl)methyl)-1,1′-biphenyl (LBIX) and 1,2-phenylenediacetic acid (H2HEA) as ligands. The analysis of the single crystal structure reveals that 1 possesses a ladder-like chain structure, which extends into a 3D architecture through π···π interactions. 1 was identified through powder X-ray diffraction analysis (PXRD), elemental analysis (EA), infrared spectroscopy (IR) and thermogravimetric analysis (TGA). It can be seen from the luminescence experiment that 1 has high Ksv value (Cr2O72−: 1.51 × 104 M−1, CrO42−: 1.16 × 104 M−1 and Fe3+: 1.26 × 104 M−1) and lower detection limit (Cr2O72−: 1.14 μM, CrO42−: 1.88 μM and Fe3+: 1.14 μM), it is utilized as a multi-response sensor to recognition Fe3+, CrO42− and Cr2O72− in an aqueous solution. Mechanisms in which fluorescence quenching occurs have been examined using techniques such as PXRD, UV–vis absorption spectra, scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Due to its excellent selectivity, high sensitivity and strong stability, it is suitable for detecting Fe3+, CrO42− and Cr2O72− ions as a fluorescent probe.

Synthesis of novel conducting triblock copolymer poly(thiophene-co-pyrrole-co-aniline) by chemical oxidative polymerization method for gas sensor application

The conducting triblock copolymer P(Th-co-Py-co-Ani) of thiophene (Th), pyrrole (Py), and aniline (Ani) has been synthesized by chemical oxidative polymerization method using anhydrous iron (III) chloride (FeCl3) as an oxidizing agent in presence of acetonitrile solvent at 0–8°C. Characterizations of the synthesized copolymer were performed by Attenuated total reflection (ATR)-Fourier transform infrared (FTIR) spectroscopy, powder X-ray diffraction analysis (PXRD), UV-Vis spectroscopy, elemental analysis (CHNS), Thermogravimetric analysis (TGA) and Scanning electron microscopy (SEM). Notably, UV-Vis spectroscopy revealed that triblock copolymers exhibit highly conjugated conducting polymer backbone, essential for its electrical conductivity and suitability for various applications. The prepared P(Th-co-Py-co-Ani) material was investigated for the gas sensing property of several gases such as ammonia, acetone, carbon monoxide, ethanol and methane. The gas sensing study revealed that P(Th-co-Py-co-Ani) demonstrates promising gas sensing capabilities, particularly at room temperature.

Production technique and multi-analytical characterization of a paint-plastered ceiling from the Late Antique villa of Negrar (Verona, Italy)

The research focuses on analyzing the production techniques and materials of a Roman paint-plastered ceiling from a Late Antique Roman villa near Negrar (Verona, Italy), recently uncovered. Stylistic features of the decoration, found in reworked collapse debris during the villa’s excavation, date the ceiling to the original construction phase in the 4th century CE. The paper presents the protocol we adopted for recovering and analyzing the painted decoration of the villa, which was in-laboratory recomposed in its original layout after a meticulous and systematic retrieval of fragmented materials. Microsamples of mortar and pigment were then taken to fully reconstruct the execution technique and raw materials used in the paint-plastered ceiling, detailing the application of the tectorium and pigment preparation. Mortar samples were analyzed to define preparatory layer properties, using various analytical techniques including Transmitted-Light Polarized Optical Microscopy (TL-OM) and Scanning Electron Microscopy with Energy Dispersive X-Ray Analysis (SEM-EDS). Optical reflected-light microscopy detected guide incisions on the preparatory mortar, while Reflected-Light Optical Microscopy (RL-OM) revealed the microstratigraphy of pictorial micro-layers. Micro-samplings of painted decorations were conducted to define pigment palettes, determining their mineralogical composition through X-Ray Powder Diffraction (XRPD) analysis coupled with micro-Raman analyses for the determination of carbon-based compounds. The research aims to establish a comprehensive protocol for future endeavors, integrating archaeological reassembly with precise micro-analyses of pigments and mortars, deciphering the intricate layout of ancient, fragmented decorations. This study is the first of its kind in Northern Italy, overcoming challenges posed by fragmented and reworked artifacts in previous research, enabling detailed analytical studies like those conducted here. Moreover, this study of the paint-plastered ceiling of the Late Roman villa of Negrar aims to provide a new impulse for the knowledge of Late Antique painting techniques and materials, which were only marginally considered within Roman painting tradition so far.

Hydrazine metal complexes as a single source in the mechanochemical preparation of metallic magnetic nanoparticles and investigation of their magnetic hyperthermia properties

Ferromagnetic metallic cobalt and nickel nanoparticles were synthesized by intramolecular metal-hydrazine ligand oxidation reduction reaction in basic media and the solid state. Nickel nanoparticles Ni1 and Ni2 are obtained from two complexes, Ni(N2H4)2(C2O4) and Ni(N2H4)2(HCO2)2, respectively. X-ray powder diffraction (XRD) and energy-dispersive X-ray (EDX) data show pure fcc crystal structures of nanoparticles. Scanning electron microscopy (SEM) images revealed both Ni1 and Ni2 nanoparticles have agglomerated sphere morphologies. The crystallite size estimated by using the Scherer method for Ni1 and Ni2 were 18.7 and 6.2 nm. Vibrating sample magnetometer (VSM) data show the coercivity of metallic nickel samples Ni1 and Ni2 are 50 and 153 Oe, respectively. Both nanoparticles cause an increase in the temperature of water under applied alternative magnetic field and showed specific loss power (SLP) of 70 W/g and 104.8 W/g, respectively. The same method is used in preparation of cobalt nanoparticles from two complexes, Co(N2H4)2(C2O4) and Co(N2H4)2(HCO2)2. XRD analysis data show both nanoparticles have hcp crystal structure. SEM images show nanosheet structure with sheet thickness of 10 to 30 nm. Coercivity of Co1 and Co2 nanoparticles obtained by VSM and Hc are 182 and 171 Oe, respectively. In spite of high coercivity in both Co1 and Co2 nanoparticles, the magnetic hyperthermia heating effects are not observed in practice and specific loss power (SLP) is zero.