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[Display omitted] • A direct-to-metal (DTM) coating was prepared with long-lasting anti-corrosion performance. • The synergistic effect of dopamine methacrylate and fluorine compounds on corrosion protection was studied. • PUA coatings had great water-repellency, anti-contamination, and transparency properties based on NP-GLIDE structures. Aluminum and its alloys have been widely used in our lives. However, Aluminum and its alloys is prone to corrosion, especially in harsh environment. In recent years, hydrophobic coatings were used in the corrosion protection of metal. But, the low surface tension of resins made them have a worse wettability on metal which had high surface tension, resulting in a worse adhesion of these coatings. Herein, we developed a long-lasting anti-corrosion direct-to-metal polyurethane NP-Glide coating based on the coordination effect of polyphenol and dual cross-linking. In comparative evaluation, the corrosion protection and anti-contamination performances of direct-to-metal polyurethane NP-Glide coating are significantly improved by the introduction of functional monomer dopamine methacrylamide (DMA) and TEMAc-8. The PU coatings with 10 wt% TEMAc-8 possesses high impedance value (|Z| 0.01Hz > 109 Ω•cm2) after 40 days of immersion in 3.5 wt% NaCl solution, exhibiting a great pull-off adhesion both in dry and wet coating, and a long-term anti-corrosion performance for aluminum alloy protection. [ABSTRACT FROM AUTHOR]

Background: Oral health represents a public health problem due to its remarkable social impact and medical costs. Crenotherapy with sulfur water is shown to be a complementary, less toxic, and traumatizing therapy, but the number of studies that evaluate the effect of natural mineral waters effect on oral health are scarce. The aim of this pilot study is to evaluate the impact of thermal water therapy on the oral health of the participants, assessing parameters such as plaque index, gingival bleeding index and periodontal probing depth as well on the perception of symptoms of oral mucosa diseases (OMD). Methods: An observational, longitudinal and comparative study was designed, and 90 thermalists were randomly allocated to two treatment groups for 14 days: Thermal sulfuric natural mineral water of the Amarante Thermal baths group (TW_TA group) (n = 45) or saline solution (control group) (n = 45), in May 2022. The study was based on clinical observation and application of a self-response questionnaire involving sociodemographic data and quality of life assessment. The evaluation was carried out in 2 different moments: before and at the end of treatment (14 days). Results: The study involved 90 thermal practitioners, evenly split between the TW_TA group and a control group. Most participants were women (70%), with a similar average age in both groups. Oral examination showed a high prevalence of filled and missing teeth, and around 25% of participants used removable prostheses, predominantly in the control group. Thermal treatment had a positive impact on oral health. In the TW_TA group, gingival bleeding significantly decreased from 68.9% to 40%, while it remained unchanged in the control group. Periodontal health improved, with no participants in the TW_TA group having pockets deeper than 5 mm by the end of the study, indicating reduced periodontal pathology. Also, plaque levels dropped in both groups after treatment, as assessed by the O'Leary index. Additionally, quality of life related to OMD improved, particularly in the TW_TA group. The overall reduction in symptoms was significant, although the differences between groups were not statistically significant. Conclusions: This study demonstrates the positive effects of thermal water treatment on oral health, including reduced gingival bleeding and plaque levels, along with improved quality of life related to OMD. Further targeted research is needed to explore the benefits of thermal water effects and optimize oral health practices in Portugal using thermal waters. [ABSTRACT FROM AUTHOR]

To enhance the energy release of Al powder in solid propellant, ploy (difluoroaminomethyl-3-methylethoxybutane) (PDF), which has difluoroamino (NF2), was utilized to improve energy and promote combustion efficiency. In this study, Al with three distinct powder sizes (29 μm, 13 μm, and 1~3 μm) was coated with PDF using the solvent/non-solvent method, leading to the formation of Al/PDF composites. The morphology and characteristics of Al/PDF were then characterized. The results demonstrated that all powder sizes of Al/PDF had core-shell structures, and NF2 of the PDF layer on the Al surface maintained the original structure. The TG curves indicated the amount of the PDF layer related to the powder sizes. Furthermore, Al/PDF exhibited greater hydrophobicity. NF2 prompted Al/PDF, with better catalysis on ammonium perchlorate (AP) decomposition. Compared to Al powder, the ignition delay of Al/PDF was significantly shortened. For mixed samples of Al/PDF and AP, NF2 shorted the ignition delay, improving combustion stability, extending the combustion duration, and forming volatile fluorine compounds. These findings underscore the effects of NF2 in Al/PDF composites, which enhances the energy release of Al and holds promising potential applications. [ABSTRACT FROM AUTHOR]

Experimental evidence for hypervalent compounds of second‐row elements is still scarce in literature. Here, we present the first report of the long‐sought binary, hypervalent trifluorooxygenate anion [OF3]−. It was isolated in solid Ne matrices under cryogenic conditions after reacting oxygen difluoride with free fluoride ions from laser ablation of alkali metal fluorides MF (M=Li−Cs). VSEPR theory and calculations at the CCSD(T) level predict a C2v‐symmetric T‐shape structure with one short and two long O−F bond lengths in [OF3]−. This is confirmed experimentally by FTIR spectroscopy in combination with isotopic labeling. Analysis of the natural local molecular orbitals shows the presence of one 2c–2e and one 3c–4e bond each. Natural resonance theory indicates the importance of the stability of [OF2]⋅− for the stability of [OF3]−. Although free [OF2]⋅− was not detected, the species MOF2 (M=Na−Cs) could be observed in the same experiments, which are best described as contact ion pairs of M+[OF2]⋅−. [ABSTRACT FROM AUTHOR]

To enhance the ignition and combustion characteristics of boron (B), in this study, a suitable, energetic fluorinated group (NF2) that can improve energy and promote combustion efficiency was utilized and B/NF2 composites (B/PDB) with three different particle sizes (10–20 μm, <5 μm, and 0.5–2 μm) were prepared through energetic fluorinated surface modifications with a PDB layer, a copolymer of difluoroaminomethyl-3-methylethoxybutane and 3,3′-bis(azidomethyl)oxetane, coated on the surface of B. The morphology and structure of B/PDB were characterized via the FTIR, SEM, TEM, and XPS techniques. The results indicate that all B/PDB particle sizes were successfully coated by NF2 on the surfaces of B particles through the PDB layer. The TG curves in the thermal analyses were used to determine the amount of the PDB layer of B/PDB with different particle sizes. Based on the DSC curves, NF2 of composites with better catalysis during ammonium perchlorate (AP) decomposition. Additionally, the effects of NF2 on both B/PDB and B/PDB with AP were investigated through PY-GC/MS, ignition, and combustion. Compared with pure B, NF2 significantly improved the thermal conductivity, thereby decreasing the ignition delay of B/PDB, and the ignition delay of B/PDB with AP. The combustion of B/PDB and AP was more intense, extending the combustion duration, forming volatile fluorine compounds, and increasing combustion reaction efficiency. In general, this energetic fluorinated-centred surface modification has potential applications to enhance the ignition and combustion characteristics in B. [ABSTRACT FROM AUTHOR]

The 2,2‐difluoroethyl group is an important lipophilic hydrogen bond donor in medicinal chemistry, but its incorporation into small molecules is often challenging. Herein, we demonstrate electrophilic 2,2‐difluoroethylation of thiol, amine and alcohol nucleophiles with a hypervalent iodine reagent, (2,2‐difluoro‐ethyl)(aryl)iodonium triflate, via a proposed ligand coupling mechanism. This transformation offers a complementary strategy to existing 2,2‐difluoroethylation methods and allows access to a wide range of 2,2‐difluoroethylated nucleophiles, including the drugs Captopril, Normorphine and Mefloquine. [ABSTRACT FROM AUTHOR]

Per- and polyfluoroalkyl substances (PFAS) are a group of fluorinated synthetic chemicals that are highly recalcitrant, toxic, and bio-accumulative and have been detected in biosolids worldwide, posing potential risks to humans and the environment. Recent studies suggest that the organic C-F bond in PFAS can be destructed and potentially mineralised into inorganic fluorides during thermal treatment. This study focuses on thermodynamic equilibrium investigations and the fate of fluorine compounds post-PFAS destruction during biosolid thermal treatment. The results indicate that gas-phase fluorine compounds are mainly hydrogen fluoride (HF) and alkali fluorides, whereas solid-phase fluorine compounds include alkaline earth fluorides and their spinels. High moisture and oxygen content in the volatiles increased the concentration of HF in the gas phase. However, adding minerals reduced the emission of HF in the gas phase significantly and enhanced the capture of fluorine as CaF2 spinel in the solid phase. This study also investigates the effect of feedstock composition on the fate of fluorine. High ash content and low volatile matter in the feedstock reduced HF gas emissions and increased fluorine capture in the solid product. The findings of this work are useful in designing thermal systems with optimised operating conditions for minimising the release of fluorinated species during the thermal treatment of PFAS-containing biosolids. [ABSTRACT FROM AUTHOR]

This review comprehensively explores fluoride removal from phosphogypsum, focusing on its composition, fluorine-containing compounds, characterization methods, and defluorination techniques. It initially outlines the elemental composition of phosphogypsum prevalent in major production regions and infers the presence of fluorine compounds based on these constituents. The study highlights X-ray photoelectron spectroscopy (XPS) as a pivotal method for characterizing fluorine compounds, emphasizing its capability to determine precise binding energies essential for identifying various fluorine species. Additionally, the first-principle density functional theory (DFT) is employed to estimate binding energies of different fluorine-containing compounds. Significant correlations are observed between the total atomic energy of binary fluorides (e.g., of alkali metals, earth metals, and boron group metals) and XPS binding energies. However, for complex compounds like calcium fluorophosphate, correlations with the calculated average atomic total energy are less direct. The review categorizes defluorination methods applied to phosphogypsum as physical, chemical, thermal, and thermal-combined processes, respectively. It introduces neural network machine learning (ML) technology to quantitatively analyze and optimize reported defluorination strategies. Simulation results indicate potential optimizations based on quantitative analyses of process conditions reported in the literature. This review provides a systematic approach to understanding the phosphogypsum composition, fluorine speciation, analytical methodologies, and effective defluorination strategies. The attempts of adopting DFT simulation and quantitative analysis using ML in optimization underscore its potential and feasibility in advancing the industrial phosphogypsum defluorination process. [ABSTRACT FROM AUTHOR]

This study investigated the effect of fluoride and boron compound additives on the synthesis and hydration process of calcium aluminate (CA2). The analysis showed that the temperature of the full synthesis of CA2 without mineralizing additives was 1500 °C. However, the addition of fluorine and boron compounds at 1% and 3% significantly reduced the synthesis temperature to a range of 1100–1300 °C. The addition of fluoride compounds did not result in the formation of fluoride compounds from CaO and Al2O3, except for the calcium borate phase (Ca3(BO3)2) under certain conditions. In addition, the cellular parameters of the synthesized calcium aluminate phases were not affected by the use of these additives. Hydration studies showed that fluoride additives accelerate the hydration process, potentially improving mechanical properties, while boron additives slow down the reaction with water. These results highlight the relevance of fluoride and boron additives to the synthesis process and hydration kinetics of calcium aluminate, suggesting the need for further research to optimize their application in practice. TG studies confirmed the presence of convergence with respect to X-ray determinations made. SEM, EDS and elemental concentration maps confirmed the presence of a higher Al/Ca ratio in the samples and also showed the presence of hexagonal and regular hydration products. [ABSTRACT FROM AUTHOR]

This document is an editorial from the International Journal of Molecular Sciences titled "Recent Advances on Fluorine Chemistry." The purpose of the document is to showcase the latest findings in fluorine chemistry. It discusses the unique properties of fluorine and how they affect the reactivity of molecules. The document also explores various aspects of lanthanide fluoride research, the development of innovative fluorination methods, and the selective addition of fluorine to multiple bonds. Additionally, it highlights the promising areas of aminofluorination reactions, classical methods of functionalization and heterocyclization, and the field of fluoroalkylation. The document concludes by mentioning the use of biocatalysis in fluorination reactions and the formation of the tetrafluoroisopropyl group. [Extracted from the article]

The pilot-scale fluoropolymer incineration study conducted by the Karlsruhe Institute of Technology (KIT) represents a significant stride in understanding the environmental impact of fluoropolymer disposal. Fluoropolymers' End-of-Life Fluoropolymers, high-performance plastics [...]

Background and Aims: Using fissure sealant is one of the most effective methods of preventing pit and fissure decay. Fluoride has been added to various materials as a known anti-caries agent. Fluorinated graphene (FG) has gained attention due to its unique properties. The specific structural characteristics of graphene fillers, besides having antibacterial properties by increasing the rate of fluoride release and charge and neutralizing the acidic pH of the environment, is a suitable option in many treatments. This study investigated the effect of addition of fluorinated graphene nanoparticles on the fluoride release in Fissurit®, a commercial fissure sealant. Materials and Methods: In this in vitro study, fluorinated graphene oxide (FGO) with bright white color was prepared. After synthesis, 0, 1, 2 and 4 by weight percent were added to the fissure sealant (Fissurit®). Then, the release of fluoride in this material was measured and compared with the commercial fissure sealant containing fluoride (Fissurit®). Results: According to the obtained results, the amount of fluoride released from groups with different percentages of FGO had a direct relationship with the percentage of FGO addition. Also, at different times, there was a significant difference between the groups with FGO and the control group without FGO (P<0.001). Conclusion: Addition of FGO to the fluorinated fissure sealant caused the release of fluoride and the possibility of recharging it. The power of releasing fluoride and its recharging in fissure sealant with FGO was higher than the fluorinated fissure sealant, but its fluoride was discharged at a faster rate. [ABSTRACT FROM AUTHOR]

Due to the specific properties provided by fluorine atoms to biomolecules, amino acids with fluorinated side chains are of great interest for medicinal chemistry and chemical biology. Among them, α-fluoroalkyl-α-amino acids constitute a unique class of compounds. In this review, we outline the strategies adopted for their syntheses in enantiopure or enantioenriched forms and their incorporation into peptides. We then describe the consequences of the introduction of fluorine atoms in these compounds for the modulation of their hydrophobicity and the control of their conformation. Emerging applications are presented in the areas of enzyme inhibition, medicinal chemistry, hydrolytic stability of peptides, antimicrobial peptides, PET, and 19F NMR probes. [ABSTRACT FROM AUTHOR]

This review is devoted to the synthesis and application of fluoro‐substituted 1,2,3‐triazoles. The analysis of the available studies of fluorinated triazoles indicates exceptional value properties especially for biomedical research, despite the significant limitations of synthetic methods of their preparation. In general, it can be noted that today there are only two strategic approaches to obtaining fluorinated triazoles. First, Huisgen 1,3‐dipolar cycloaddition, which is significantly limited by stability problems of fluorine‐unsaturated dipolarophiles, regioselectivity and low conversion problems. This approach allows preferentially obtaining 4‐fluoro‐1‐substituted triazoles. Second, nucleophilic substitution, which allows obtaining 5‐fluoro‐1,4‐disubstitution, but under rather hard conditions and is also limited by the nature of the substituent. Finally, there are practically no protocols for the preparation difluorotriazoles, and, also, the use of fluoro‐substituted 1,2,3‐triazoles as regents for further transformations is not enough studied. [ABSTRACT FROM AUTHOR]

This review mainly focused on the synthesis of 3(5)-trifluoromethylpyrazoles via condensation of trifluoromethyl-β-diketones with hydrazines. Also, a special emphasis is led on the biological potential of fluorine containing compounds and pyrazoles in introduction section. We have covered all the literature reported condensation reactions of trifluoromethyl-β-diketones with hydrazines. [ABSTRACT FROM AUTHOR]

To provide a more straightforward protocol, we envisioned that a boron-catalyzed carboxylic acid enolate formation approach, previously developed by some of us, [28] would enable direct -trifluoromethylthiolation of carboxylic acids (Scheme 1c). Direct -Trifluoromethylthiolation of Carboxylic Acids Enabled by Boron Catalysis Carboxylic acid, boron catalyst, trifluoromethylthiolation, data science, drug modification, fluorine compounds Keywords: carboxylic acid; boron catalyst; trifluoromethylthiolation; data science; drug modification; fluorine compounds EN carboxylic acid boron catalyst trifluoromethylthiolation data science drug modification fluorine compounds 2210 2214 5 10/31/23 20231127 NES 231127 Graph Incorporation of fluorine atoms and fluoro-functional groups in a molecule has been essential for the development of pharmaceuticals and agrochemicals. [Extracted from the article]

The anticarcinogenic potential of a series of 1,5-disubstituted tetrazole-1,2,3-triazole hybrids (T-THs) was evaluated in the breast cancer (BC)-derived cell lines MCF-7 (ER+, PR+, and HER2−), CAMA-1 (ER+, PR+/−, and HER2−), SKBR-3 (ER+, PR+, and HER2+), and HCC1954 (ER+, PR+, and HER2+). The T-THs 7f, 7l, and 7g inhibited the proliferation of MCF-7 and CAMA-1, HCC1954, and SKBR-3 cells, respectively. The compounds with stronger effect in terms of migration and invasion inhibition were 7o, 7b, 7n, and 7k for the CAMA-1, MCF-7, HCC1954, and SKBR-3 cells respectively. Interestingly, these T-THs were the compounds with a fluorine present in their structures. To discover a possible target protein, a molecular docking analysis was performed for p53, p38, p58, and JNK1. The T-THs presented a higher affinity for p53, followed by JNK1, p58, and lastly p38. The best-predicted affinity for p53 showed interactions between the T-THs and both the DNA fragment and the protein. These results provide an opportunity for these compounds to be studied as potential drug candidates for breast cancer treatment. [ABSTRACT FROM AUTHOR]

The aim of this review was to provide dentists with comprehensive information regarding dentin hypersensitivity. This includes presenting its etiology, outlining the process of diagnosis, discussing clinical management strategies, and exploring technical approaches aimed at alleviating sensitivity. Dentin hypersensitivity is characterized by distinctive short, sharp pain arising from exposed cervical dentin in response to various external stimuli. The etiological factors cause two specific changes in teeth. First, the dentin surface must be exposed and denuded, which requires the loss of enamel or gingival recession combined with the loss of cementum. The second condition is the opening of the dentin tubules to allow the sensory mechanisms in the pulpal area following stimulation of the dentin surface. The accurate diagnosis of dentin hypersensitivity before receiving therapies is critical for successful treatment. The diagnosis of the disease starts through investigating the medical history of the patient and examination. In the examination, some techniques such as air stream and water rinsing are used in order to simulate the stimulating factors and to determine the degree of pain of the patient. Numerous materials and methods have been proposed to reduce or alleviate sensitivity. These materials typically exert their effects by either sealing dentin tubules or disrupting the transmission of nerve impulses. Generally, the primary approach in addressing dentin hypersensitivity involves the utilization of toothpaste containing potassium salts and fluoride. Newly introduced materials and in-office methods for treating dentin hypersensitivity include bioactive glasses, iontophoresis, CPP-ACP, and lasers. [ABSTRACT FROM AUTHOR]

Proton-Exchange Membrane Fuel Cells have emerged as a game-changer in the automotive sector due to their operational efficiency and eco-friendly nature. The impact of NAFION and the Proton-Exchange Membrane Fuel [...]

Objectives: To compare the microhardness and ion content of three glass-ionomer cements (GICs) during setting and up to 15 days, to composite resin-based material in vitro, and after 5 to 10 years in vivo. Method and materials: Disks of three GICs, EQUIA Fil, Riva Self Cure, and Ketac Molar were examined in vitro for microhardness using Vickers indentations after 15 to 60 minutes, 24 hours, and 8 and 15 days, and compared to composite material, Spectrum. The ion content of the GIC and composite was analyzed using the energy dispersive spectroscopy program of a scanning electron microscope. A primary second molar restored with GIC normally exfoliated after 5 years, and a third molar restored with GIC extracted due to periodontitis after 10 years, were sliced through the restoration buccolingually, and the microhardness of the restoration and of the dentin was measured. Results: In comparison to composite material, the Vickers value for the GICs were similar or better after 24 hours to 15 days. The amount of fluorine was three times higher in EQUIA Fil and Riva Self Cure in comparison with Ketac Molar, after 20 days. After 5 years in vivo, the microhardness of GICs was similar to dentin and after 10 years it was significantly higher than that of the dentin. Conclusion: The microhardness of GICs was comparable to composite material after only 24 hours. In vivo the microhardness of GICs increased and after 10 years in vivo it was higher than that of the dentin. After 20 days the amount of fluorine was still high in Riva Self Cure and EQUIA Fil. [ABSTRACT FROM AUTHOR]

Background & Aim: Enterococcus faecalis, play a significant role in plaque formation and tooth decay. Mouthwashes are one of the tools used to reduce decay..the aim of study was comparision of fluorine total with chlorhexidine on Enterococcus faecalis. Material and Methods: In this in-vitro study a total of 24 samples (18 samples in each groups and 6 control samples) were examined, the diameter of the growth inhibition zone of Enterococcus faecalis was compared between two mouthwashes of fluorine total and chlorhexidine 0.2% Enterococcus faecalis was first cultured on a blood agar plate and incubated for 24 hours at 37 °C. The bacteria were then cultured on 18 plates of blood agar (9 plates for chlorhexidine mouthwash and 9 plates for fluorine total mouthwash). To evaluate the absence of bacterial inside the mouthwashes, 2 plates containing fluorine total and chlorhexidine mouthwash were cultured separately. The plates were prepared by well method, then the growth inhibition zone in the two study groups was measured and analyzed by Repeated Measure ANOVA test of 25th version of SPSS software. Results: The growth inhibition zone in the chlorhexidine and fluorine total group was 15/94±0.8 mm and 18/61±1.4 mm, respectively, which was in the chlorhexidine group, which is statistically significant (P<0/0001). Conclusion: Fluorine total mouthwash is more effective than chlorhexidine mouthwash on enterococcus faecalis. [ABSTRACT FROM AUTHOR]

The use of 'forever chemicals' in the European Union would be largely banned under a proposal issued by the European Chemicals Agency. At the same time, more US states continue [...]