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Tetrafluoroethylene (TFE) terpolymers have emerged as advantageous substitutes for polytetrafluoroethylene (PTFE). Therefore, they are being considered as alternatives to PTFE in many application areas. The advantages of TFE terpolymers include their facile processability at elevated temperatures, their solubility in some polar organic solvents, their inertness against aqueous acids, aqueous bases and a large number of mostly nonpolar organic solvents, their low dielectric constant, their low refractive index as well as useful electro‐ and thermochemical properties. This review on TFE terpolymers focuses on their processing including shaping and surface modification as well as on selected properties including wettability, dielectric properties, mechanical response behavior, chemical stability, and degradability. Applications including their use as elastomeric sealing material, liner and cladding layer as well as their use as material for membranes, microfluidic devices, photonics, photovoltaics, energy storage, energy harvesting, sensors, and nanothermitic composites will be discussed. The review concludes with a discussion of the future potential of TFE terpolymers and scientific challenges to be addressed by future research on TFE terpolymers. [ABSTRACT FROM AUTHOR]

Polytetrafluoroethylene (PTFE) exhibits outstanding properties such as high‐temperature stability, low surface tension, and chemical resistance against most solvents, strong acids, and bases. However, these traits make it challenging to subject PTFE to standard polymer processing procedures, such as thermoforming and hot incremental forming. While polymer processing at temperatures above the melting point of PTFE is already demanding, the typically large molar mass of PTFE results in extremely high melt viscosities, complicating the processing of PTFE. Also, PTFE tends to decompose at temperatures close to its melting point. Therefore, fluoropolymers obtained by copolymerizing tetrafluoroethylene (TFE) with various co‐monomers are studied as alternatives to PTFE (e.g., fluorinated ethylene‐propylene (FEP)), combining its advantages with better processability. TFE terpolymers have emerged as desirable PTFE alternatives. This review provides an overview of the synthesis with various comonomers and microstructural analysis of PTFE terpolymers and the relationships between the microstructures of TFE terpolymers and their properties. [ABSTRACT FROM AUTHOR]

Introduction: The human immunodeficiency virus (HIV) remains a significant global health concern, with a reported high infection rate of 38.4 million cases globally; an estimated 2 million new infections and approximately 700,000 HIV/ AIDS-related deaths were reported in 2021. Despite the advent of anti-retroviral therapy (ART), HIV/AIDS persists as a chronic disease. To combat this, several studies focus on developing inhibitors targeting various stages of the HIV infection cycle, including HIV-1 protease. This study aims to synthesize and characterize novel glyco diphenylphosphino metal complexes with potential HIV inhibitory properties. Method: A series of new gold(I) thiolate derivatives and three bimetallic complexes, incorporating amino phosphines and thiocarbohydrate as auxiliary ligands, were synthesized using procedures described by Jiang, et al. (2009) and Coetzee et al. (2007). Structural elucidation and purity assessment of the synthesized compounds (1-11) were conducted using micro-analysis, NMR, and infrared spectrometry. Results and Discussion: Using molecular modeling techniques, three of the metal complexes were identified as potential HIV protease inhibitors, exhibiting strong binding affinity interactions with binding pocket residues. These inhibitors demonstrated an ability to inhibit the flexibility of the flap regions of the HIV protease, similar to the known HIV protease inhibitor, darunavir. This study sheds light on the promising avenues for the development of novel therapeutic agents against HIV/AIDS. [ABSTRACT FROM AUTHOR]

Various aspects of electrospun fibers prepared from terpolymer of tetrafluoroethylene (TFE), hexafluoropropylene (HFP), and vinylidene fluoride (VDF) (THV)/acetone solutions at two applied voltages, THV/acetone solutions having Texas montmorillonite with two ratios, and THV/ethyl acetate solutions using two needle sizes are described. Fibers from THV/acetone and THV/ethyl acetate solutions showed shallow indentations and pores, respectively. The clay, functioning as electrospinning agent, did not influence the fiber morphology, but yielded narrower fiber diameter distribution and the thinnest fibers. Heterogeneous fiber diameter distribution and increase in the fiber diameters were observed by lowering the voltage for fibers of THV/acetone solutions. Fibers from THV/ethyl acetate solutions had the largest diameter and the broadest diameter distribution. Electrospun THV fibers having both hydrophobic characteristics with nearly 140° water contact angles and oleophilic properties with oil contact angles less than 45° might have applications in areas such as water/oil separation.

Aggregation of asphaltenes remains a scientific challenge. In the present contribution, at first, transverse magnetization relaxation (T2) data from low-field NMR measurements of the asphaltenes from heavy, medium-heavy, or light crude oil samples were recovered. Following this, diffusion ordered spectroscopy nuclear magnetic resonance (NMR) spectra of these asphaltenes were acquired to obtain average molecular weights (Mw) of asphaltene aggregates. Analyzing the relaxation and diffusion behavior of asphaltene aggregates as a function of solution percentage and hence molecular weights are utilized to explain the difference between light, medium-heavy and heavy crude oil asphaltenes in aggregate formation. The main results suggest that light crude oil asphaltenes form a small but significant number of aggregates. In contrast, heavy crude oil asphaltenes demonstrate a more complicated picture at high concentrations with small, medium, and large aggregates. The relaxation behavior of medium-heavy asphaltenes is similar to those of heavy crude oil asphaltenes in diluted solutions and similar to light crude oil asphaltenes in concentrated solutions. Diffusion NMR results showed that the light crude oil asphaltene samples have a relatively smaller aggregate size, higher diffusion coefficient, and hence a smaller molecular weight than the samples extracted from heavy crude oils. [ABSTRACT FROM AUTHOR]

Introduction: Pomegranate seed is rich in oil, and seed oil of pomegranate consists of conjugated fatty acids with different percentages. Objectives: The current contribution covers how to determine percentages of different isomeric conjugated fatty acids. Methods: The percentages of these isomers are analysed by quantitative nuclear magnetic resonance (qNMR) using benzoic acid as an internal reference chemical with a well‐defined amount. Linear mathematical equations are developed for the quantitative analysis of fatty acids found in pomegranate seed oil. Results: The developed approach is utilised for the pomegranate seed oils prepared in the laboratory and tested for commercial samples. Among the oils derived at the laboratory, the Yeni Hicaz pomegranate cultivar seeds yielded the highest fraction of punicic acid. Among the acids, punicic acid was the one with the highest fraction, while linolenic acid was the one with the lowest percentage. Conclusions: These results are important in identifying pomegranate seed oils. Among the commercial samples tested with the current approach, only one of them showed similar content analysis as in the laboratory‐derived oils. The previously established qNMR spectroscopy approach was extended by adding an internal certified reference chemical and applied on pomegranate seed oils (PSOs) to determine the valuable chemicals of PSO samples in the micro‐litre range. The approach uses linear mathematical equations. Only Company 2 sample showed similar fractions of valuable acids to those of laboratory derived PSO samples. Both private and governmental food testing laboratories could apply the presented qNMR approach for certifying and assessing the contents of other edible oils. [ABSTRACT FROM AUTHOR]

In the present report, we describe the biosynthesis of palladium nanoparticles (PdNPs) using nontoxic and renewable Punica granatum peel extract. Synthesis of PdNPs was monitored via color change and confirmed by Ultraviolet-visible (UV-vis) spectroscopy. Fourier-transform infrared spectroscopy (FT-IR) revealed the active role of phytochemicals derived from Punica granatum in reduction and stabilization of nanoparticles. X-ray diffraction (XRD) pattern showed that the synthesized PdNPs have face-centered cubic crystalline structure. The morphological characterizations carried out using scanning electron microscopy (SEM) equipped with energy dispersive X-ray and high-resolution transmission electron microscopy (HRTEM) revealed that PdNPs are spherical and well distributed and the average size of PdNPs is 22 ± 5 nm. Then, the catalytic activity of PdNPs was tested successfully in the reduction of 4-nitrophenol. Biosynthesis of PdNPs using pomegranate peel extracts was remarked as an alternative low-cost and eco-friendly green method alternative to the conventional chemical and physical methods. [ABSTRACT FROM AUTHOR]

In this contribution, the relaxation and diffusional behaviors of low viscous fluids, water and methanol confined into mesoporous silica and controlled size pore glass were investigated. The engineered porous systems are relevant to geologically important subsurface energy materials. The engineered porous proxies were characterized by Brunauer–Emmett–Teller (BET) surface analyzer, nuclear magnetic resonance (NMR) spectroscopy, and electron microscopy (EM) to determine surface area, pore-wall protonation and morphology of these materials, respectively. The confined behavior of the low viscous fluids was studied by varying pore diameter, fluid-to-solid ratio, temperature, and pressure, and then compared to bulk liquid state. Both relaxation and diffusion behaviors for the confined fluids showed increasing deviation from pure bulk fluids as the fluid-to-solid ratio was decreased, and surface-to-volume ratio (S/V) was varied. Variable pressure deuteron NMR relaxation of confined D2O and confined methanol, deuterated at the hydroxyl or methyl positions, were performed to exploit the sensitivity of the deuteron quadrupole moment to molecular rotation. The methanol results demonstrated greater pressure dependence than those for water only in bulk. The deviations from bulk liquid behavior arise from different reasons such as confinement and the interactions between confined fluid and the nano-pore wall. The results of the present report give insight into the behavior of low viscosity fluid in nano-confined geometries under different state conditions. [ABSTRACT FROM AUTHOR]

Olive oil is an important part of the human diet worldwide. Its production has increased every year. Adulteration detection and labeling olive oils with a declaration of geographical origin now is a new challenge for scientists. First, in this report, we summarize the contributions on quantitative analysis of fatty acids in Turkish olive oils. Then, we describe the reports of the minor constituents including phenols and aromatics of these olive oils, followed by less studied properties such as inorganic metal contents, bioactivity, and adulteration detection. While analyzing both the major and minor components of Turkish olive oils, we show also a comparison of their contents with other olive oils from Spain, Italy, Greece, and Tunisia. We conclude with lessons learned and aspects of scientific future work need to be done for the protection of the authenticity of olive oils. Abbreviations: EVOO: Extra Virgin Olive Oil; VOO: Virgin Olive Oil; OEVOO: Organic Extra Virgin Olive Oil; ROO: Refined Olive Oil; TG: Triglycerides; FA: Fatty Acid; PUFA: Polyunsaturated Fatty Acid; MUFA: Monounsaturated Fatty Acid; TPC: Total Phenolic Compounds; GA: Gallic Acid; PDO: Protected Designation of Origin; PGO: Protected Geographical Origin; EU: European Union; ISO: International Standardization of Organization; IOC: International Olive Council; NIR: Near Infrared; MIR: Mid Infrared; NMR: Nuclear Magnetic Resonance; GC: Gas Chromatography; MS/O: mass spectrometry-olfactometric; DOSY: Diffusion Ordered SpectrsocopY; HPLC: High-Pressure Liquid Chromatography; FID: Flame Ionization Detector; MVS: Machine Vision System; ETAAS: Electrothermal Atomic Absorption Spectrometry; FAAS: Flame Atomic Absorption Spectrometry; HS-SPME: Headspace solid-phase microextraction; E-nose: Electronic-nose; SDE: Simultaneous Distillation and Extraction; AEDA: Aroma Extract Dilution Analysis; PCA: Principle Component Analysis; ANOVA: Analysis of Variance; HCA: Hierarchical Cluster Analysis; LDA: Linear Discriminant Analysis; PLS-DA: Partial Least Squares-Discriminant Analysis; OPLS-DA: Orthogonal Partial Least Square-Discriminant Analysis; DFA: Discriminant Function Analysis; ABTS: 2,2ʹ-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) used as an antioxidant assay; SNP: Single Nucleotide Polymorphism. DPPH assay: (2,2-diphenyl-1-picryl-hydrazyl-hydrate) free radical method and an antioxidant assay; DNA: Deoxyribonucleic Acid; CAPS: Cleaved Amplified Polymorphic. [ABSTRACT FROM AUTHOR]