Solid Complexes Research Articles

Synthesis and Characteristics of Cu/N-Codoped Ti3C2T x MXene Using Copper-Aniline Solid Complex and Application to Simultaneous Electrochemical Sensing of Adenine and Guanine in Artificial Sweat

This work evaluates the electrochemical performance of copper and nitrogen codoped Ti3C2T x MXene (or Cu@N − Ti3C2T x ) for purine sensing. Aniline/cupric ion solid complex was synthesized by reaction of aniline with CuCl2 (Cu(aniline)2Cl2). Subsequently, the obtained CuCl2-aniline coordination complex was mixed with Ti3C2T x MXene and carbonized in an autoclave. Subsequently, a new electrochemical sensor was designed based on a hybrid of Cu/N-codoped Ti3C2T x MXene on a glassy carbon electrode modified to be a Cu@N − Ti3C2T x electrode. The nanomaterials were characterized using Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy techniques. The analytes were determined using differential pulse voltammetry. The detection limits were 0.01 for adenine and 0.02 μM for guanine, while the linear response ranges of both analytes were from 0.1 to 10 μM. This sensing device has been further employed in the individual and simultaneous detection of adenine and guanine in artificial sweat with 98–102% recoveries.

Faithfully Flat Descent of Quasi-Coherent Complexes on Rigid Analytic Varieties via Condensed Mathematics

Abstract Faithfully flat descent of pseudo-coherent complexes in rigid geometry was proved by Mathew. In this paper, we generalize the result of Mathew to solid quasi-coherent complexes on rigid analytic varieties, which have been introduced by Clausen and Scholze by means of condensed mathematics.

Reversible solid bromine complexation into Ti3C2Tx MXene carriers: a highly active electrode for bromine-based flow batteries with ultralow self-discharge

The robust and reversible solid bromine complexation effect was incorporated into electrodes, endowing bromine-based flow batteries with ultralow self-discharge.

Harnessing reductive BF2-complexation via Ru(II)-catalyzed N-O cleavage of isoxazoles.

Developed here is a highly fluorescent organic N,O bidentate BF2 complex from isoxazole in the presence of a Ru(II) catalyst. Herein, the complexation proceeds via a selective N-O cleavage of the isoxazole ring. The complex shows absorption (λmax,abs) in the range of 352-363 nm with an extinction coefficient (ε) in the range of 8000-64 000 M-1 cm-1, and fluorescence emission (λmax,em) in the range of 413-485 nm with a Stokes shift of 61-125 nm having quantum yield up to 33%. Apart from the solution state, the solid BF2 complex 2u exhibits absorption at 405 nm and strong fluorescence emission at 550 nm with a quantum yield of 26.9%.

A novel cationic β-cyclodextrin decorated with a choline-like pendant exhibits Iodophor, Mucoadhesive and bactericidal properties

Iodine is a vital microelement and a powerful antiseptic with a rapid and broad spectrum of action. The development of iodophor compounds to improve the solubility and stability of iodine is still challenging. Here, we report the synthesis of a novel cationic β-cyclodextrin bearing a choline-like pendant (β-CD-Chol) designed to complex and deliver iodine to bacterial cells. The characterization of β-CD-Chol and the investigation of the inclusion complex with iodine were performed by NMR spectroscopy, mass spectrometry, UV–vis spectrophotometry, isothermal titration calorimetry, and dynamic light scattering. The functionalization with the positively charged unit conferred improved water-solubility, mucoadhesivity, and iodine complexation efficiency to the β-CD scaffold. The water-soluble β-CD-Chol/iodine complex efficiently formed both in solution and by solid-vapor reaction. The solid complex exhibited a significant stability for months. Iodine release from the inclusion complex was satisfactory and the bactericidal activity was proved against a Staphylococcus epidermidis strain. The absence of cytotoxicity tested on human keratinocytes and the improved mucoadhesivity make β-CD-Chol a promising drug delivery system and an appealing iodophor candidate for iodine-based antisepsis including mucosa disinfection.

Applications of Fenton Coagulation for wastewater treatment: a review

The most diverse forms of pollution and contamination, especially from the industrial sector, reinforce the need to optimize industrial processes in the search for reducing waste generated or even creating and improving appropriate techniques for removing organic compounds in solid waste and effluents. Wastewater resulting from chemical processes, in general, has a complex composition and causes environmental problems when not treated appropriately. An efficient proposal for the treatment of effluents of high chemical complexity and high concentration of suspended solids is Fenton Coagulation. This process reconciles the coagulation process with iron ions and reuses the residual iron concentration to apply a subsequent treatment, the Fenton process. Therefore, the objective of this work is to address the hybrid Fenton coagulation process and discuss important aspects of its use for the treatment of effluents.

The reaction characteristics and mechanism of polymer non-catalytic reduction (PNCR) for NOx removal

To overcome the defects of the traditional selective non-catalytic reduction (SNCR) process (e.g., low efficiency, narrow temperature range), a new modified SNCR technology based on the solid complex polymer reducing agents, also called polymer non-catalytic reduction (PNCR), was investigated both in the laboratory and pilot scale to reveal its reaction characteristics and mechanism. The PNCR process demonstrates excellent removal efficiency (about 90%) of NO in furnace in the wide temperature range (850–1150 °C), and possesses promising application feasibility with an average NOx emission concentration of 68.72 mg·m−3 even on unstable industrial operating conditions. The NO removal behaviors influenced by O2, temperature, or water steam illuminate the unique O2-independent and H2O-promoted reaction characteristics of PNCR in the wide temperature range. The thermogravimetric infrared spectra/mass spectrometry (TG-IR/MS) results further reveal a pyrolysis-assisted formation mechanism of active NH2/NH free radicals without the requirement of O2 and high temperature, which avoids the overoxidation of active radicals and accounts for the wide denitrification temperature window, low oxygen compliance and high denitrification efficiency of PNCR process. The excellent NO removal performance as well as the unique reaction characteristics/mechanism of PNCR forebode its broad industrial application prospect in the field of flue gas cleaning.

SYNTHESIS AND CHARACTERIZATION OF NEW METAL COMPLEXES WITH TRIDENTATE HYDRAZONE LIGAND

Considering necessity of application of Schiff base ligands, containing hydrazone moiety, there were synthesized 2-hydroxy-1-naphtaldehyde acetylhydrazone and its metal complexes. A tridentate ligand with hydrazone moiety was synthesized on the basis of acetylhydrazine and 2-hydroxy-1-naphthoic aldehyde. The characterization and structure of it was identified by IR, UV- and NMR-spectroscopy. The electronic absorption spectrum of the ligand shows absorption bands in the range of max 237–320 nm. 1H NMR (300 MHz, CD4O):  6.90–8.21, 9.31, 10.52. Recrystallization occured from an ethanol. Mel¬ting point of the ligand was 21530C. Yield was 80%. There were acquired complexes of the Schiff base ligand with zinc and manganese. Colored solid complexes of zinc and manganese (II), respectively, yellow and brown colors with the obtained ligand were synthesized in ethanol medium. Yield for complexes was 75 and 73 %, respectively for zinc and manganese complex. The molar ratio of ligand and me¬tal in the complex was 2:1. The structure of the complexes was confirmed by elemental analysis, IR-, UV-, and thermogravimetric analysis

Synthesis and Spectral identifications of new azo – Schiff base ligand(4Cl-2DIBP) derived from (para-aminobenzylamine) with its some metallic complexes

The New Heterocyclic ligand 4-chloro-2-(((4-((4,5-diphenyl-1H-imidazol-2-yl) diazenyl ) benzyl)imino)methyl) phenol (4Cl-2DIBP) was prepared from the condensation of para-aminobenzylamine with 4,5-diphenyl imidazole, followed by the condensation of the resulting compound with 5- chloro-2- hydroxy benzaldehyde. Different analytical and characterization techniques including (Mass,1HNMR, FT-IR and UV-Vis. spectroscopy and C.H.N elemental analysis) in the investigation of Newly prepared ligand. A series of Novel solid metal complexes of this ligand with Co (II), Ni (II), Cu (II), Zn ((II), Cd (II), and Hg (II) were prepared and all complexes were characterization by techniques above, excluding the Mass and the 1H-NMR spectroscopy of some prepared solid metal complexes and the use of flame atomic absorption spectroscopy to determine the percentages of metal ions in the prepared complexes also studied the magnetic susceptibility and molar conductivity of the metal complexes dissolved in DMSO at 1 × 10-3 M concentration laboratory temperature. The results of this studies showed that the coordination sites for the new Azo-Schiff base ligand with Co (II), Ni (II), Cu (II), Zn ((II) , Cd (II) and Hg(II) were to be through nitrogen of the imidazole ring, and the nitrogen of azo group,. The Electronic spectral and magnetic measurement data predict octahedral structure of the complexes. All complexes showed that Non-electrolytes properties.

Solid dispersion complex triclabendazole preparations with succinic acid and their fasciolocidal activity

The purpose of the research is to test the efficacy of triclafascid and two solid dispersion complex preparations based on the triclabendazole substance against fasciolosis in cattle and sheep. Materials and methods. Complex preparations of triclabendazole (TCB) formulations: Succinic Acid (SA): Polyvinylpyrrolidone (PVP) (1: 1 : 8) and TCB: SA: Arabinogalactan (AG) (1: 1 : 8) were obtained by combined solid-stategrinding of the components in a fiber drum on an LE-101 ball mill at a roll rotation speed of 60 rpm with a process module of 1: 17 for 1 to 6 hours with sampling for analysis (HPLC) for changes in the TCB solubility. A comparative test of the efficacy of triclafascid and new solid dispersions (SD) of TCB complexes with SA against fascioliasis of sheep and cattle was conducted in the North-Eastern Federal District of the Caucasus in March-April 2023. To determine the Fasciola infection rate in animals, fecal samples were individually taken and examined by the Fülleborn methods using saturated aqueous NaCL solution and sequential washing. The drug efficacy was recorded at 25-30 days after deworming in analogy with "critical test". The results were statistically processed by the Student-Fisher method using Microsoft Excel 2007. Results and discussion. The resulting TCB and SA complexes with polymers had an increased solubility (up to 59–70 times) that depended on the polymer nature. The efficacy of new TCB dosage forms against fascioliasis in sheep at a dose of 1.5 mg/kg, i.e. 0.5 mg/kg less than the therapeutic dose as compared with oral triclafascid was 90.0 and 100%, respectively, and 85.7% in cattle at a dose of 2.0 mg/kg for the active substance.

Recovery of high‐purity‐4‐chloroguaiacol from bleaching wastewater by a heterogeneous extraction method

AbstractBACKGROUNDDuring the pulping and bleaching processes, 4‐chloroguaiacol accounts for a large proportion of chlorine containing pollutants. In this study, a heterogeneous extraction method for extracting 4‐chloroguaiacol from the bleaching wastewater by using the intermediate as the solid phase extraction agent is proposed.RESULTSThe solid intermediate with the molar ratio of 4‐chloroguaiacol to calcium 2:1 is firstly prepared. It is used for reacting with the crude 4‐chloroguaiacol in the bleaching wastewater to generate the end solid complex with the molar ratio of 4‐chloroguaiacol to calcium 4:1. It is verified to be that the high‐purity 4‐chloroguaiacol can be released from the simple thermal decomposition of the end solid complex.CONCLUSIONAt an optimum extraction condition including 30 °C reaction temperature, the pH value of 7, using the deionized water as the solvent, the extraction yield and the purity of 4‐chloroguaiacol reached 89.2% and 97.8%. Furthermore, after 15 cycle extraction times, the extraction rate of 4‐chloroguaiacol can still reach 86.3%. The extraction yield and the purity of 4‐chloroguaiacol reached 68.15% and 99.56% when the guaiacol content was lower than 25 mg/L at the bleaching wastewater. © 2023 Society of Chemical Industry (SCI).

Synthesis of (R)-(6-Methoxyquinolin-4-yl)[(1S,2S,4S,5R)-5-vinylquinuclidin-2-yl]methanol Tetraphenylborate Ion-Pair Complex: Characterization, Antimicrobial, and Computational Study.

The (R)-(6-Methoxyquinolin-4-yl)[(1S,2S,4S,5R)-5-vinylquinuclidin-2-yl]methanol (quinine)-tetraphenylborate complex was synthesized by reacting sodium tetraphenyl borate with quinine in deionized water at room temperature through an ion-pair reaction (green chemistry) at room temperature. The solid complex was characterized by several physicochemical methods. The formation of ion-pair complex between bio-active molecules and/or organic molecules is crucial to comprehending the relationships between bioactive molecules and receptor interactions. The complex under study was examined for antimicrobial activity. All theoretical calculations were carried out in vacuum and water using the B3LYP level 6-311G(d,p) levels of theory. The theoretical computation allowed for the prediction and visualization of ionic interactions, which explained the complex's stability. The results of energy optimization showed that the Q-TPB complex is stable with a negative complexation energy. The obtained geometries showed that the boron (B-) and nitrogen (N+) in piperidine of the two molecules tetraphenylborate and quinine are close to each other, which makes it possible for ions to interact. The modest energy gap between HOMO and LUMO showed that the compound was stable. The computation of the electron transitions of the two models by density functional theory (TD-DFT) in the solvent at the theoretical level B3LYP/6-311G(d,p) allowed for the detection of three UV/visible absorption bands for both models and the discovery of a charge transfer between the host and the guest. The UV absorption, infrared, and H NMR are comparable with the experimental part.

Investigation of Physicochemical Properties of Tapioca Starch–Methyl Myristate Complexes

AbstractComplexation can be utilized to modify starch properties. In this study, tapioca starch–methyl myristate (SM) complexes are prepared by mixing tapioca starch and methyl myristate (MM) in water at 90 °C. The MM amount is varied at 1%–10% w/w to study its effects on the complexes’ physicochemical properties, which are characterized using spectroscopic, thermal, crystallinity, particle size, and microscopic analyses. The complexes are stable crystalline materials, as iodine cannot replace complexed MM. In water, these complexes aggregate to form two different sizes of 29.5–162.7 nm (23%–58% population) and 711.2–7086.7 nm (42%–77% population), which melt at 90–95 °C. Solid complexes form porous morphologies, which start degrading at 260.3–263.4 °C, indicating high thermal stability. An in vitro digestibility study using α‐amylase shows that the higher the MM amount is, the slower the starch degradation. At 120 min digestion time, the complexes produce 11%–16% lower reducing sugar than native starch (S). This shows that starch complexation with MM complexes can produce starch materials with slower digestibility. For the kinetic analysis, the Weibull model fits better than the exponential model for analyzing the digestion kinetics of SM complexes by the α‐amylase enzyme.

Study on the structural and photophysical properties of N-acyl amino acid europium complexes

In this paper, a series of acyl amino acid europium complexes (Eu[CH3(CH2CH2)nCONHCH(CH3)COO]3, n = 0 ∼ 5) were synthesized using N-acyl amido alanine as ligands, and their structures and photophysical properties were studied.The structural and functional group information of europium complexes was obtained by elemental analysis, as well as infrared and hydrogen nuclear magnetic spectral analysis (1H NMR). The theoretical structure of the complexes was obtained by density functional theory (DFT) calculations; the theoretical structure of the complex was shown to be reliable by the comparison of theoretical and experimental vibrational and 1H NMR spectra. Additionally, the photophysical properties of the solid complexes at room temperature were determined by analysis of Ultraviolet–visible spectroscopy(UV–vis) and luminescence spectra. From the test results, it can be seen that the complex had good light absorption capacity in the range of 200–––300 nm; By comparison of the luminescence intensities of the complexes and EuCl3 proved that acyl amino acid ligands played a role in sensitizing Eu3+ characteristic luminescence. In addition, the effect of solution concentration on fluorescence performance has been studied. It can be inferred that complexes with longer carbon chains are less prone to aggregation in solution (increasing repulsive forces with increasing hydrophobicity), and the concentration, where fluorescence quenching occurs, is higher. Moreover, the solvent effect on the luminescence performance of the complexes was investigated by testing the luminescence spectrum of the complexes with different carbon chain lengths in a methanol solution(0.01 mol/L). Finally, the variable temperature spectral analysis provided information on the temperature-dependent variation of the luminescence properties of the complexes. The fluorescence performance of complexes with different carbon chain lengths that having different changing trends with temperature, with long carbon chain complexes exhibiting better high-temperature fluorescence stability.

Synthesis, spectroscopic, molecular docking, theoretical calculations, DNA‐binding, and anticancer activity studies of gold (III), platinum (II), palladium (II), and ruthenium (III) complexes with Girard‐T reagent

This article details the synthesis of new Girard‐T reagent ligands. Condensation of 2‐hydroxyacetophenone or 2‐acetyl‐thiophene with Girard‐T reagent results in new hydrazone ligands. The interaction of these Girard‐T hydrazones with transition metal chlorides, like Au (III), Ru (III), Pd (II), and Pt (II), produces different complexes. Elements and spectrum analyses (IR, UV–Vis, EI‐mass, and 1H NMR) were used to characterize the isolated solid complexes, as well as conductimetric and magneto‐chemical studies. Metal complexes can have different geometrical configurations, including square planar and octahedral coordination. The DMOL3 method, which is a part of the Material Studio package, was also utilized for structure optimization. Horowitz–Metzger and Coats–Redfern methods were utilized to calculate the various thermodynamic and kinetic parameters. The ligands and the complexes of their metal were evaluated for anticancer activity against carcinoma cervix (Prostate) and the mammary gland female breast (MCF‐7) cell line having cancer, with promising results. Among these compounds, the Ru (III) and Pt (II) complexes' anticancer activity against (MCF‐7) cell lines, comparable with that of 5‐fluorouracil were carried out and their interactions were performed by molecular docking simulations against MCF‐7 (PDB ID: 3W2S) receptor.

Preparation and characterization of the Br-HPI complex of Fe(III) and their applications for dye solar cell by synthesized α-Fe2O3 nanoparticles in a novel method

The derivative of five member heterocyclic ligand containing imidazole rings 4-bromo-2-(4,5-diphenyl-1H-imidazol-2-yl) phenol [Br-HPI] and their complex with Fe(III) are reported. This ligand was characterized by elemental analysis, FT-IR and 1H NMR spectroscopy. The solid complex was characterized by IR spectra, molar conductivity and magnetic moment. The results suggest that the metal is bonded to the ligand through the phenolic oxygen and the pyridine nitrogen forming chelates with (1:2) (metal: ligand) stoichiometry, and the octahedral geometry for the complex. The complex has photolysis by novel method that using UV. cell to synthesis α-Fe2O3 nanoparticles. The nanoparticles have been indicate by transmission electron microscopy (TEM), X-ray diffraction (XRD), scanning electron microscopy (SEM), with average particles size in the range 11 to 25 nm. The α-Fe2O3 nanoparticles have been applied a photo anode to fabrication dye solar cell (ITO\α-Fe2O3 Nps\rodamine 6G dye\Ag nanofilme\ITO) with energy efficiency conversion about 2.5 %.

Encapsulation of hyperoside with acyclic cucurbiturils: Supramolecular binding behavior, water solubility and in vitro antioxidant activity

Hyperoside (Hyp) is a natural flavonol glycoside widely present in plants, which possesses important pharmacological activities including anti-inflammatory, anti-viral, organ-protection, antioxidant, and anti-tumor, etc. However, its poor water solubility and low oral bioavailability severely limit its further development for pharmaceutical uses. In this work, solid inclusion complexes of Hyp with two acyclic cucurbiturils (ACBs, M1 and M2) were prepared by the method of suspension. The formation of inclusion complexes was confirmed by Fourier transform infrared (FT-IR), powder X-ray diffraction (PXRD) and nuclear magnetic resonance (NMR) analyses. Based on Job's plot, proton nuclear magnetic resonance (1H NMR) spectroscopy, two-dimensional diffusion ordered spectroscopy (2D-DOSY), two-dimensional rotating-frame Overhauser enhancement spectroscopy (2D-ROESY) and molecular docking experiments, a 1:1 inclusion mode was rationally proposed. The binding stability constants (Ks) were determined by fluorescence titration, up to 4.22 × 104 and 6.97 × 104 L·mol-1 for Hyp/M1 and Hyp/M2, respectively. After inclusion complexation with ACDs, the water solubility of Hyp was elevated by more than 300-fold, which was much superior to that with cyclodextrins. Furthermore, in vitro antioxidant activity of Hyp was significantly promoted by formation of inclusion complexes. These results would inspire new strategies for further developments of Hyp for pharmaceutical uses.

Electroplating wastewater treatment by in-situ formation of organic anions and inorganic anions intercalated layered double hydroxides

The electroplating wastewater containing various metal ions was treated by adding sodium dodecyl benzene sulfonate (SDBS) and regulating pH value, and the resulting precipitates were characterized by X-ray diffraction (XRD). The results showed that organic anions intercalated layered double hydroxides (OLDHs) and inorganic anions intercalated layered double hydroxides (ILDHs) were in-situ formed to remove heavy metals during the treatment process. In order to reveal the formation mechanism of the precipitates, SDB− intercalated Ni–Fe OLDHs, NO3− intercalated Ni–Fe ILDHs and Fe3+-DBS complexes were synthsized by co-precipitation at various pH values for comparison. These samples were characterized by XRD, Fourier Transform infrared (FTIR), element analysis as well as the aqueous residual concentrations of Ni2+ and Fe3+ were detected. The results showed that OLDHs with good crystal structures can be formed as pH≤7, while ILDHs began to form at pH = 8. When pH < 7, complexes of Fe3+ and organic anions with the ordered layered structure were formed firstly, and then with increase in pH value, Ni2+ inserted into the solid complex and the OLDHs began to form. However, Ni–Fe ILDHs were not formed when pH ≤ 7. The Ksp (Solubility Product Constant) of OLDHs was calculated to be 3.24 × 10−19 and that of ILDHs was 2.98 × 10−18 at pH = 8, which suggested that OLDHs might be easier to form than ILDHs. The formation process of ILDHs and OLDHs were also simulated through MINTEQ software, and the simulation output verified that OLDHs could be easier to form than ILDHs at pH ≤ 7. Information from this study provides a theoretical basis for effective in-situ formation of OLDHs in wastewater treatment.

Encapsulation through concern of inter and intramolecular hydrogen bonding of 2-hydroxybenzoic acid with C-alkyl calix[4]resorcinarenes

The host-guest complexation of 2-hydroxybenzoic acid (compound 4) with four C-alkyl calix[4]resorcinarenes (compounds 3a-3d) were investigated in aqueous, solid state and gas phase. The solid inclusion complexes were prepared by solvent evaporation method. The solubility of compound 4, compounds 3a-3d and inclusion complexes were analyzed in different polar, non-polar and dipolar solvents. The binding stoichiometric ratio of inclusion complexes was analyzed by phase solubility and jobs plot method. UV–Visible and fluorescence spectral studies were provided the information about binding constant, stoichiometric ratio and Gibb's free energy values. The solid inclusion complexes were characterized by FTIR, 1HNMR , 13CNMR and powder X-ray diffraction studies to determine the interactions between the compound 4 and compounds 3a-3d. The surface morphology of all were characterized by scanning electron microscopic imagining analysis. The biological activity of all were done by phosphomolybdate antioxidant assay and kirby-bauer antibacterial studies. The proposed structure of inclusion complexes were optimized for the two orientations using DFT B3LYP 3–21 G method in the gas phase. The more stable orientations of inclusion complexes were predicted from energy and band gap energy values

Particularities of the formation of the air masses structure in the tunnel during the train movement

The effect of aerodynamic factors on the rolling stock and railway infrastructure has been analysed. The formation of air mass structure in tunnel structures during the movement of high-speed rolling stock has been investigated. The processes of aeroelastic interaction of rolling stock with tunnel portal structures are analysed by means of numerical simulation. The description of mathematical models and the ways of their three-dimensional realization in the Solid Works Flow Simulation software complex are presented. Methods of finite elements and volumes for the solution of the set tasks are used. The results of the numerical research of velocity fields near the tunnel portal area obtained with the help of the developed mathematical models for the cases of entry and exit of the rolling-stock into the tunnel are given. The complex structure of air masses formation in the gap between the train body and tunnel lining which leads to increased resistance to the train movement in the tunnel is revealed. The patterns in the changes of pressure dynamics on the surface of the head fairing when the train enters the tunnel are found. The fact of negative effect of high and low pressure zones, as well as their abrupt difference, on the locomotive crew and passengers has been established.