CeCl3 Research Articles

Synthesis of 5H-Pyrrolo[3,4-b]Pyridin-5-Ones via a Cerium Chloride Catalyzed Multicomponent Cascade Process: A One-Pot Approach Incorporating Ugi-Zhu 3CR, Aza Diels–Alder, N-Acylation, and Aromatization Reactions

We have synthesized α-isocyano-β-phenylpropionamides 5 (a–c) using a two-step process and then created a new series of poly-substituted 5H-pyrrolo[3,4-b]pyridin-5-ones 12 (a–o) via a multi-component reaction. Most of the reported literature used scandium triflate and either benzene or toluene as solvents, which are not good for the environment. We have identified cerium(III) chloride as the catalyst and acetonitrile as the solvent for conversion, which is harmless to the environment. The synthetic strategy involved Ugi-Zhu 3CR (UZ-3CR), Aza Diels–Alder, N-acylation, and aromatization steps, yielding products in the range of 65–85%.

Computational Simulation and Biophysical Study on Cerium Chloride-Induced B-to-Z Transition in (CG) n DNA.

Rare earth elements have been shown to trigger the B-to-Z DNA transition in diverse self-assembled branched DNA architectures. Herein, we investigated the influence of cerium chloride on the conformational changes of DNA sequences containing repeated cytosine-guanine (CG)6-12 or guanine-cytosine (GC)6-12 sequences. The CD results show that (CG)6-12 repeats were susceptible to the formation of Z-DNA at low concentrations of CeCl3. On the other hand, (GC)6-12 is unable to undergo B-Z DNA transition and instead exhibits condensation with a similar amount of CeCl3. The CD signature was found to be different and unique in both alternate repeats during the interaction with CeCl3. The sequence-specific effects on the B-Z transition are based on the order of nucleotides in DNA. With the addition of EDTA, the Z-form of DNA is reverted to the native B-form. Further, we have reported the positive zeta potential of CeCl3-induced Z-DNA in contrast to the negative zeta potential of B-DNA. The differential zeta-potential value during the B-Z transition is complementary to the conformational changes of DNA. The molecular simulation study also supports the sequence-specific conformational change between the B- and Z-forms of DNA molecules. This newly described reversible topological and sequence-dependent transition is crucial for understanding the structural and biological roles of Z-DNA in response to CeCl3.

Dynamics of Hydrogen Peroxide Accumulation During Tip Growth of Infection Thread in Nodules and Cell Differentiation in Pea (Pisum sativum L.) Symbiotic Nodules.

Hydrogen peroxide (H2O2) in plants is produced in relatively large amounts and plays a universal role in plant defense and physiological responses, including the regulation of growth and development. In the Rhizobium-legume symbiosis, hydrogen peroxide plays an important signaling role throughout the development of this interaction. In the functioning nodule, H2O2 has been shown to be involved in bacterial differentiation into the symbiotic form and in nodule senescence. In this study, the pattern of H2O2 accumulation in pea (Pisum sativum L.) wild-type and mutant nodules blocked at different stages of the infection process was analyzed using a cytochemical reaction with cerium chloride. The observed dynamics of H2O2 deposition in the infection thread walls indicated that the distribution of H2O2 was apparently related to the stiffness of the infection thread wall. The dynamics of H2O2 accumulation was traced, and its patterns in different nodule zones were determined in order to investigate the relationship of H2O2 localization and distribution with the stages of symbiotic nodule development in P. sativum. The patterns of H2O2 localization in different zones of the indeterminate nodule have been partially confirmed by comparative analysis on mutant genotypes.

N-Halosuccinimide-CeCl3 Transient Charge-Transfer Complexes as Semi Heterogeneous Photocatalyst in Cyclization of N-Propargylamides.

In this work, we used photoinert anhydrous cerium(III) chloride, to form a transient charge-transfer (CT) complex with NXS (N-bromosuccinimide or NBS and N-iodosuccinimide or NIS) in acetonitrile. These transient CT complexes acted as a semi-heterogeneous photocatalyst. These complexes allowed the Ce(III) ions to absorb light, turning them into strong electron donors that transferred electrons to NXS. This created halide radicals from NXS radical anions, helping to turn N-propargylamides into oxazole aldehydes. Experiments with DMPO and spin-trapping showed that a radical-based mechanism followed a single electron transfer (SET) pathway. Notably, CeCl3 was reused after the reaction without much decomposition, as it was regenerated and separated through simple filtration.

ЕЛЕКТРОХІМІЧНЕ ОСАДЖЕННЯ НАНОКРИСТАЛІЧНОГО КОМПОЗИТУ НІКЕЛЬ–ЦЕРІЮ(IV) ОКСИД З НИЗЬКОТЕМПЕРАТУРНОГО ЕВТЕКТИЧНОГО РОЗЧИННИКА ДЛЯ ВИГОТОВЛЕННЯ ЕЛЕКТРОКАТАЛІЗАТОРІВ ДЛЯ ВОДНЕВОЇ ЕНЕРГЕТИКИ

This study reports the patterns of electroplating a composite coating containing phases of nanocrystalline metallic nickel and cerium dioxide from an electrolyte based on a new generation of ionic liquids, deep eutectic solvents (DESs). Currently, the use of DESs is an extremely promising direction for the electrochemical deposition of electrocatalytic coatings for electrochemical energy, particularly for "green" hydrogen energy. The electrolyte for deposition contained a liquid eutectic mixture of choline chloride and urea (the so-called "reline", a typical representative of DESs), in which nickel (II) chloride (0.1 mol/dm³) and cerium (III) chloride (0.2–0.4 mol/dm3) were dissolved. According to the results of energy-dispersive X-ray analysis and XRD investigations, the composite coating contains approximately 12–16 at.% cerium, presumably in the form of cerium dioxide. A reaction scheme for the formation of the composite nanocoating, which includes a combination of chemical and electrochemical stages, is proposed. It was found that the incorporation of cerium oxide leads to a significant increase in electrocatalytic activity (compared to nickel coating) in the cathodic hydrogen evolution reaction and anodic oxygen evolution and urea oxidation reactions. It is hypothesized that the observed enhancement in electrocatalytic effect is due to the formation of additional active catalytic sites on the surface containing cerium in different oxidation states (e.g., Ce(+4)/Ce(+3)), which can act as electron carriers in both cathodic and anodic reactions. A significant advantage of this composite is its bifunctionality as an electrocatalyst, meaning it can be used for both cathodic and anodic processes. The obtained results can be used in the development of new high-efficiency processes for the electrochemical synthesis of "green" hydrogen.

Synergistic effect of cerium chloride and calcium chloride alters calcium signaling in keratinocytes to promote epidermal differentiation.

Epidermal keratinocytes undergo morphological and functional changes during differentiation, eventually being enucleated to become corneocytes. Calcium has been shown to be involved in various cellular functions of epidermal cells, including proliferation, differentiation, and apoptosis. Cerium is a lanthanide-series element and rare earth metal. For skin, cerium oxide has been investigated for use in absorbing UV and promoting wound healing. However, the functions and physiological effects of inorganic cerium on the skin have rarely been investigated. Here, we focused on cerium's function in epidermal keratinocytes and its interaction with calcium by investigating their effects on cell differentiation and intracellular calcium concentration. This study showed that applying cerium chloride to epidermal keratinocytes altered calcium signaling. It also suggested that cerium and calcium induced an increase in intracellular calcium concentration and promoted keratinocyte differentiation.

Synthesis of amino juglone derivatives with adjuvant activity against clinical isolated methicillin-resistant staphylococcus aureus strains

1,4-naphthoquinones hydroxyderivatives belong to an important class of natural products and have been known as a favored scaffold in medicinal chemistry due to their multiple biological properties. Juglone is one of the most important 1,4-naphthoquinone extracted from juglandaceae family showing a good antibacterial activity. In this study, we report the synthesis of aminojuglone derivatives through Michael addition reaction using Cerium (III) chloride heptahydrate (CeCl3·7H2O) as catalyst. The synthesized aminojuglone derivatives were evaluated for their antibacterial properties against sensitive, clinical resistant Gram-positive and Gram-negative bacterial strains. Compound 3c showed a good antibacterial activity similar to cloxacillin (2 µg/mL) against the clinically resistant S.aureus. The antibiotic adjuvant activity of compounds was evaluated in combination with three clinically use antibiotics. The combination of compounds 3a, 3b, 3e, 3 h-3 l, 3n and 3o with cloxacillin showed remarkable adjuvant activity against clinically resistant S. aureus (66-fold potentiation of cloxacillin activity). 3e is the only compound consistent with the concept of antibiotic adjuvant, presenting insufficient antibacterial activity (MIC > 128 µg/mL) and potentiate the activity of cloxacillin (66-fold) with synergistic effect. A structural characterization of 3e was carried out for the first time using X-ray diffraction technic. Moreover, compound 3e did not show a cytotoxic activity on sheep red blood cells.

Mechanisms of biological effectiveness of ionic forms of metals of variable valence in respiratory medicine

Background: The task to develop new drugs containing metals of variable valence requires systematization of our knowledge, experimental and clinical studies. The aim of the study: To investigate the mechanisms of the effectiveness of the mineral complex containing metals of variable valence in the treatment of respiratory diseases, to conduct preclinical trials and clinical testing of a new inhalation mineral solution. Materials and methods: The ability of cerium (III) ions to exhibit reducing properties was demonstrated by carrying out chemical reactions of cerium (III) chloride and sulfate with potassium permanganate in the presence of sodium hydroxide or sulfuric acid (respectively). Preclinical studies of acute toxicity were carried out on laboratory mice and rats in accordance with the rules of bioethics and with generally accepted ethical standards for the treatment of animals, based on the standard operating procedures of the university, which comply with the rules adopted by the European Convention for the Protection of Vertebrate Animals used for research and other scientific purposes (Strasbourg, 1986). Clinical testing of two forms of the mineral complex for inhalation (1. Inhalation solution for nebulizer – Renerium; 2. intranasal spray) was carried out on 6 groups of volunteers in compliance with human rights and the principles of conducting medical research involving a person as a subject, declared on the 18th General Assembly of the World Medical Association (Helsinki, Finland), voluntary informed consent, approved by the local ethical committee. Results: Mineral preparation for inhalation therapy of patients with acute respiratory diseases does not show acute toxicity in preclinical studies on laboratory animals. The mechanism of action of the drug is most likely associated with the regulation of redox reactions at the level of the cell membrane, mitochondria and cell nucleus, which is manifested by anti-inflammatory and regenerative activity in the mucous membrane of the respiratory tract and alveolar apparatus. Both forms of the drug are well tolerated. A pronounced clinical efficacy of the drug Renerium in the form of inhalation through a compressor inhaler was noted in the case of a 5-day course of treatment, 5 ml once a day. Conclusion: Experimental and clinical data have demonstrated pronounced anti-inflammatory and regenerative properties of a new mineral complex based on cerium (III), the mechanism of which is due to the regulation of redox reactions.

Highly Emissive Lanthanide-Based 0D Metal Halide Nanocrystals for Efficient Ultraviolet Photodetector.

Recently, lanthanide-based 0D metal halides have attracted considerable attention for their applications in X-ray imaging, light-emitting diodes (LEDs), sensors, and photodetectors. Herein, lead-free 0D gadolinium-alloyed cesium cerium chloride (Gd3+-alloyed Cs3CeCl6) nanocrystals (NCs) are introduced as promising materials for optoelectronic application owing to their unique optical properties. The incorporation of Gd3+ in Cs3CeCl6 (CCC) NCs is proposed to increase the photoluminescence quantum yield (PLQY) from 57% to 96%, along with significantly enhanced phase and chemical stability. The structural analysis is performed by density functional theory (DFT) to confirm the effect of Gd3+ in Cs3Ce1- xGdxCl6 (CCGC) alloy system. Moreover, the CCGC NCs are applied as the active layer in UVPDs with different Gd3+ concentration. The excellent device performance is shown at 20% of Gd3+ in CCGC NCs with high detectivity (7.938 × 1011 Jones) and responsivity (0.195 A W-1) at -0.1V at 310nm. This study paves the way for the development of lanthanide-based metal halide NCs for next-generation UVPDs and other optoelectronic applications.

Numeral simulation of solution mixing effect and product preparation effect in the process of preparing cerium oxide by microwave heating

Microwave heating has the characteristics of simple control and high efficiency, in which electromagnetic force plays an important role. Using the UDF function and energy equation in FLUENT software, the electromagnetic force model in the tube is established. The mixing process of cerium chloride solution under different heating modes, the mixing effect of Lorentz force and the preparation process of cerium oxide under different inlet material velocities were numerically simulated. CFD-Post and MATLAB software are used to post-process the data of the whole fluid area. Through the above analysis, the best process conditions of numerical simulation and experiment are finally determined. The results show that microwave heating has better mixing effect and lower material loss compared with conventional heating, in which electromagnetic force plays a promoting role; Under the condition of microwave heating, the product conversion rate is high, and the concentration of cerium oxide is high and distributed evenly. The more appropriate mixing method of cerium chloride and preparation method of cerium oxide are microwave heating, and the more appropriate inlet velocity of materials is 0.15 m/s.

Improving uniformity and performance of electroformed copper using rare earth element additives

Electroforming can realize high precision and complex shape parts manufacturing, making it widely used in the field of micromachining and micromanufacturing. The drawback lies in the nonuniform thickness distribution, which can cause quality issues including voids, pitting, and particles. In order to enhance the microstructure uniformity and electroforming performance, lanthanum chloride and cerium chloride were employed as additives in the copper electroforming experiment. This study analyzes the effects of lanthanum chloride and cerium chloride on the surface morphology, microhardness, tensile strength, and uniformity of electroformed copper deposits. The results show that adding rare earth elements into the electrolyte solution can improve thickness uniformity, promote ion mass transfer, and refine the copper deposit’s grain. Compared to the microstructure without adding additives, the copper deposit’s nonuniformity prepared with 1.0 g/L lanthanum chloride is 76.9% lower, and with cerium chloride, it is 72% lower. Additionally, the copper deposit prepared with lanthanum chloride exhibits superior overall quality compared to that prepared with cerium chloride.

Recovery of Cerium Salts from Sewage Sludge Resulting from the Coagulation of Brewery Wastewater with Recycled Cerium Coagulant.

Due to the high cost and limited sources of cerium coagulants, it is extremely important to take measures to recycle this raw material. This paper presents the new possibility of recovering cerium(III) chloride, cerium(III) sulphate, cerium(IV) sulphate, and potentially phosphate from sewage sludge (101.5 g/kg Ce and 22.2 g/kg total P) through a brewery wastewater treatment process using recycled CeCl3 as a coagulant. In order to recover the Ce and P, the sludge was subjected to extraction using an HCl solution. Optimal process conditions were determined by means of central composite design and response surface methodology (CCD/RSM) for three input parameters (HCl mass, reaction time, and extractant volume). Under optimal conditions (0.35 g HCl per 1 g of sludge, 40 min reaction time, extractant volume of 25 mL per 1 g of sludge), the highest efficiency obtained was 99.6% and 97.5% for Ce and P, respectively. Cerium(III) oxalate as Ce2(C2O4)3∙10H2O was precipitated from the obtained solution using H2C2O4 (99.97%) and decomposed into CeO2 (at 350 °C), which was afterwards subjected to a reaction with HCl (30%, m/m) and H2O2 (30%, m/m), which led to the crystallisation of CeCl3∙7H2O with a purity of 98.6% and a yield of 97.0%. The obtained CeO2 was also subjected to a reaction with H2SO4 (96%, m/m) and H2O2 (30%, m/m), which produced Ce2(SO4)3 with a yield of 97.4%. The CeO2 was also subjected to a reaction with only H2SO4 (96%, m/m), which produced Ce(SO4)2 with a yield of 98.3%. The filtrate obtained after filtering the Ce2(C2O4)3∙10H2O contained 570 mg/L of P, which enabled its use as a source of phosphorus compounds. The presented processes of Ce and potentially P recovery from sewage sludge originating from brewery wastewater contribute to the idea of a circular economy.

A novel isatin Schiff based cerium complex: synthesis, characterization, antimicrobial activity and molecular docking studies

In this work, a novel isatin-Schiff base L2 had been synthesized through a simple reaction between isatin and 2-amino-5-methylthio-1,3,4-thiadiazole. The produced Schiff base L2 was then subjected to a hydrothermal reaction with cerium chloride to produce the cerium (III)-Schiff base complex C2. Several spectroscopic methods, including mass spectra, FT-IR, elemental analysis, UV–vis, 13C-NMR, 1H-NMR, Thermogravimetric Analysis, HR-TEM, and FE-SEM/EDX, were used to completely characterize the produced L2 and C2. A computer simulation was performed using the MOE software program to find out the probable biological resistance of studied compounds against the proteins in some types of bacteria or fungi. To investigate the interaction between the ligand and its complex, we conducted molecular docking simulations using the molecular operating environment (MOE). The docking simulation findings revealed that the complex displayed greater efficacy and demonstrated a stronger affinity for Avr2 effector protein from the fungal plant pathogen Fusarium oxysporum (code 5OD4) than the original ligand. The antibacterial activity of the ligand and its Ce3+ complex were applied in vitro tests against different microorganism. The study showed that the complex was found to be more effective than the ligand.

Mechanochemical synthesis of cerium chlorapatite from a mixture of cerium chloride heptahydrate, dicalcium phosphate dihydrate, and calcium hydroxide for biomedical application.

Cerium ions promote osteoclastogenesis and activate bone metabolism, while cerium oxide nanoparticles exhibit potent anti-inflammatory properties, making them promising for biomedical applications. The purpose of this study was to develop and evaluate a synthesis method for sustained-release cerium-ion bioceramics containing apatite. Substituted apatite was found to be an effective biomaterial. Cerium-containing chlorapatite was synthesized using a mechanochemical method employing dicalcium phosphate, cerium chloride heptahydrate, and calcium hydroxide as raw materials. The synthesized samples were characterized using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and Raman spectroscopy. Cerium chlorapatite was successfully synthesized in the 10.1% and 20.1% samples. However, at Ce concentrations higher than 30.2%, the samples consisted of three or more phases, indicating the instability of a single phase. The method used in this study was found to be more efficient and cost-effective than the precipitation method for producing substituted apatite and calcium phosphate-based biomaterials. This research contributes to the development of sustained-release cerium-ion bioceramics with potential applications in the field of biomedicine.

Surface Characterization Gel Grown Cerium Tartrate Crystals

Cerium tartrate crystals were grown from sodium metasilicate gel and water solutions of tartaric acid and cerium chloride as the reactants. Crystals grown were spherulitic in size. The principle objective of this investigation is to determine the surface area, pore volume and pore size of CeT sample. BET surface area was calculated from the BET plot; pore size distributions were calculated using BJH model. The pore volume was measured at the single point of p/p0 = 0.05. The Adsorption / Desorption Isotherm for cerium tartrate, Pore Size Distribution by BJH Method, Pore Size Distribution by DFT method and Volume Histogram By DFT Method was studied respectively for the CeT sample. The isotherm obtained for the sample demonstrates that it belongs to the type II isotherm.

Production of an eco-friendly, effective antimicrobial and antifungal from cerium/natural bio-hydroxyapatite coating for titanium plates suitable for bone augmentation

As a promising technique for rebuilding bone defects, materials having enhanced osteoductivity and antimicrobial and fungi effects have been used for bone replacement. Accordingly, the present study aims to develop a sintered titanium (Ti) plate prepared by the cold isostatic press (CIP) coated with nano bio-natural hydroxyapatite (n-HA) via freeze-drying technique for bone substitution. Moreover, the influence of cerium chloride heptahydrate doping with different concentrations of 0.5, 2, and 8 wt% was evaluated for enhancing the osteogeneration process and antibacterial activity on titanium (Ti) plates instead of antibiotic-loaded. Physical properties showed that the n-HA/2%CeCl3 coat is the most suitable concentration with an appropriate porosity of 73.43 ± 3.52 compared to porous n-HA coating Ti plate with a porosity of 90.38 ± 0.27. The biological activity (in-vitro) study in terms of following up the apatite nucleation on the blank Ti plate and Ti/n-HA/2 % CeCl3 surfaces after immersions in SBF for up to 28 days showed the formation of spherical clusters from carbonated apatite particles on the sample's surface, with a Ca/P ratio equal to 2.26. The cytotoxicity test was examined using a bone osteosarcoma cell line (HOS). The final results confirmed minimal cytotoxicity for the plate coated with n-HA/2 % CeCl3 (3.6 %). Cell attachment results indicate the potential of the cells to adhere and spread on the surface. In addition, the antimicrobial assessment of n-HA/2 % CeCl3 coated Ti plates showed broad-spectrum activity against not only the gram-positive or gram-negative but also fungal ones.

Effect of cerium chloride on electric crystallization behavior and grain refinement of electrodeposited copper

Effect of cerium chloride on electric crystallization behavior and grain refinement of electrodeposited copper

The use of a poly cerium chloride nanocomposite as a prospective material for the preparation of a 99Mo/99mTc generator

The use of a poly cerium chloride nanocomposite as a prospective material for the preparation of a 99Mo/99mTc generator

CORROSION BEHAVIOR OF 12Cr18Ni10Ti STEEL IN LiCl–KCl MELT CONTAINING ADDITIVES OF <i>f</i>-ELEMENT CHLORIDES

When reprocessing spent nuclear fuel, it is supposed to use LiCl–KCl melt (0.49:0.51) in an inert atmosphere, all metal materials in this salt melt are extremely susceptible to corrosion, besides, during the processing of spent fuel, both the liquid (melt) and the gas phase are saturated with decay products that can act as additional oxidizing agents, increasing the aggressiveness of the environment. The pyrochemical technology of SNF includes operations such as soft chlorination, electrofining and metallization, implying the presence in the melt of compounds of chlorides of rare earth metals lanthanum, cerium and neodymium, as well as uranium(III, IV) chlorides. In this work, the corrosion behavior of 12CR18NI10TI steel in LiCl–KCl melt containing NdCl3, CeCl3, LaCl3, UCl3 and UCl4 additives up to 2 wt % was investigated. Corrosion tests lasting 100 hours were performed at a temperature of 500°C in an inert argon atmosphere. It was found that the presence of REM chlorides significantly reduces the degradation of the steel under study. The addition of (REM)Cl3 leads to the formation of a compound (REM) on the surface of the samples OCl, the thickness and continuity of which increases in the following row: LaCl3 NdCl3 CeCl3. The formation of such a compound leads to the inhibition of the corrosion process of steel 12CR18NI10TI due to salt passivation of the surface. The addition of UF4 to the melt causes significant corrosion of 12CR18NI10TI intercrystalline steel. The introduction of UF3 into the melt leads to a decrease in the corrosion rate, which is associated with the predominant interaction of trivalent uranium chloride with dissolved molecular oxygen contained in the melt, and the formation of a non-stoichiometric compound with the crystal chemical formula U3O7 on the surface of samples according to microrentgenospectral analysis.

Prompt gamma rays from fast neutron induced reactions on cerium and chlorine

Prompt gamma rays of cerium and chlorine were investigated with the FaNGaS (Fast Neutron-induced Gamma-ray Spectrometry) instrument operated at the Heinz Maier-Leibnitz Zentrum (MLZ) in Garching. The gamma radiation was emitted from (n,n’), (n,p) and (n,α) reactions induced by the irradiation of a cerium(III) chloride (CeCl3) sample with a beam of fission neutrons. Additionally, a polyvinylchloride (PVC, (C2H3Cl)n) sample was irradiated to verify possible interferences between gamma lines of cerium and chlorine. We identified 87 prompt gamma lines of cerium and chlorine. From these, we assigned 58 lines to the (n,n’) reaction in cerium (one for 136Ce, 41 for 140Ce and 16 for 142Ce), 23 to the (n,n’) reaction in chlorine (15 for 35Cl and 8 for 37Cl), 5 lines to the 35Cl(n,p)35S reaction and 1 line to the 35Cl(n,α)32P reaction. We present relative intensities and fast-neutron spectrum-averaged partial cross sections of the aforementioned gamma lines and compare them with available literature data. Identification of new lines and discussion of possible errors adds important value to the literature data found to be consistent with our results. In addition, for a counting time of 12 h we estimate the detection limits for cerium and chlorine as 1 and 2 mg, respectively.