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TheScientificWorldJournal 2024The purpose of this review was to investigate the application of metal nanoparticles in fruit shelf life extension. Despite growing interest in nanoparticles and their... (Review)
Review
The purpose of this review was to investigate the application of metal nanoparticles in fruit shelf life extension. Despite growing interest in nanoparticles and their potential applications, there are currently few effective methods for prolonging the shelf life of fruits. The study concentrated on the principles underlying the shelf life extension of metallic nanoparticles, including copper oxide, zinc oxide, silver, and titanium oxide. The biological properties of nanoparticles, especially those with antibacterial qualities, have drawn interest as possible fruit preservation solutions. Many conventional preservation methods have drawbacks, including expensive production costs, short shelf lives, undesirable residues, and the incapacity to properly keep perishable fruits in their natural environments. Techniques for extending shelf life based on nanotechnology have the potential to get around these problems. The review focused on the effective use of environmentally benign, green synthesis-produced nanoparticles to extend the fruit shelf life. The ability of these nanoparticles to successfully preserve fresh fruits was established. The results imply that fruit preservation by the use of nanoparticle synthesis techniques may be a viable strategy, offering a more effective and sustainable substitute for traditional procedures.
Topics: Metal Nanoparticles; Mangifera; Fruit; Food Preservation; Food Storage
PubMed: 38957455
DOI: 10.1155/2024/4782328 -
Open Research Europe 2024This article introduces an innovative classification methodology to identify nanowires within scanning electron microscope images.
BACKGROUND
This article introduces an innovative classification methodology to identify nanowires within scanning electron microscope images.
METHODS
Our approach employs advanced image manipulation techniques in conjunction with machine learning-based recognition algorithms. The effectiveness of our proposed method is demonstrated through its application to the categorization of scanning electron microscopy images depicting nanowires arrays.
RESULTS
The method's capability to isolate and distinguish individual nanowires within an array is the primary factor in the observed accuracy. The foundational data set for model training comprises scanning electron microscopy images featuring 240 III-V nanowire arrays grown with metal organic chemical vapor deposition on silicon substrates. Each of these arrays consists of 66 nanowires. The results underscore the model's proficiency in discerning distinct wire configurations and detecting parasitic crystals. Our approach yields an average F1 score of 0.91, indicating high precision and recall.
CONCLUSIONS
Such a high level of performance and accuracy of ML methods demonstrate the viability of our technique not only for academic but also for practical commercial implementation and usage.
PubMed: 38957297
DOI: 10.12688/openreseurope.16696.2 -
Journal of the American Chemical Society Jul 2024Metal radicals have shown versatile reactivity in modern synthetic chemistry. However, the use of zinc radicals for molecular synthesis has been barely explored. Here,...
Metal radicals have shown versatile reactivity in modern synthetic chemistry. However, the use of zinc radicals for molecular synthesis has been barely explored. Here, we show that a transient zinc radical can be formed through photoactivation of a zinc-zinc bonded compound, which is able to mediate the selective dimerization of alkenes and allenes. Treatment of dizinc compounds [Zn] [ = CHC(2,6-PrCHN)CHC(CH)(NCHCHPR); R = Ph () or Pr ()] with a diverse array of aromatic alkenes under UV irradiation (365 nm) facilely afforded the head-to-head coupling products, i.e., 1,4-dizinciobutanes in high yields. In addition, arylallenes could also be selectively dimerized by the dizinc compound to give 2,5-dizincyl-functionalized 1,5-hexadienes under the same conditions. Control reactions of [Zn] in the presence of UV irradiation isolated a zinc phenyl complex and a trimeric zinc phosphide complex resulting from C-P bond cleavage at the tridentate ligand. Reactions of photoactivated dizinc compounds with organic spin traps, i.e., 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) and 2,2'-bipyridine (2,2'-bpy), successfully isolated zinc radical trapping products [ZnOTEMP] and [Zn(2,2'-bpy)], respectively. The profile of alkene dimerization was elucidated by density functional theory calculations, which confirmed that a transient zinc radical [Zn·] was initially generated through homolytic Zn-Zn bond cleavage via photoactivation followed by single-electron transfer and radical dimerization. The unique selectivity of the current reaction was also studied computationally.
PubMed: 38957130
DOI: 10.1021/jacs.4c07390 -
Physical Chemistry Chemical Physics :... Jul 2024Ru is a metal of interest in catalysis. Monodisperse Ru clusters as catalytic sites are relevant for the development of catalysts because clusters use significantly...
Ru is a metal of interest in catalysis. Monodisperse Ru clusters as catalytic sites are relevant for the development of catalysts because clusters use significantly lower amounts of precious materials for forming active sites due to the small size of the cluster. However, retaining the mono-dispersity of the cluster size after deposition is a challenge because surface energy could drive both agglomeration and encapsulation of the clusters. In the present work Ru clusters are deposited by chemical vapor deposition (CVD) of Ru(CO) and cluster source depositions of bare Ru onto radio frequency sputter-deposited TiO (RF-TiO) substrates, TiO(100), and SiO. When supported on RF-TiO, bare Ru is encapsulated by a layer of titania substrate material during deposition with a cluster source. Ligated Ru(CO) is also encapsulated by a layer of titania when deposited onto sputter-treated RF-TiO, but only through heat treatment which is required to remove most of the ligands. The titania overlayer thickness was determined to be 1-2 monolayers for Ru(CO) clusters on RF-TiO, which is thin enough for catalytic or photocatalytic reactions to potentially occur even without clusters being part of the very outermost layer. The implication for catalysis of the encapsulation of Ru into the RF-TiO is discussed. Temperature-dependent X-ray photoelectron spectroscopy (XPS), angle-resolved XPS, and temperature-dependent low energy ion scattering (TD-LEIS) are used to probe how the cluster-surface interaction changes due to heat treatment and scanning transmission electron microscopy (STEM) was used to image the depth of the surface from side-on.
PubMed: 38957118
DOI: 10.1039/d4cp00263f -
ChemSusChem Jul 2024Catalytic C-H functionalization has provided new opportunities to access novel organic molecules more sustainably and efficiently. However, these procedures typically...
Catalytic C-H functionalization has provided new opportunities to access novel organic molecules more sustainably and efficiently. However, these procedures typically rely on precious metals or complex organic catalysts as well as on hazardous solvents or reaction conditions. Herein, a pioneering methodology for direct C-C bond formation enabled by Ligand-to-Metal Charge Transfer (LMCT) and mediated by UV irradiation has been developed using Deep Eutectic Solvents (DESs) as sustainable reaction media. This direct C-H bond functionalization via a radical addition to electrophiles was successfully confirmed over a broad scope of substrates. More importantly, this is the first example of photocatalytic C-C bond formation in DESs. An inexpensive and abundant iron catalyst (FeCl3) was used under air and mild conditions. Different functional groups were well tolerated obtaining promising results that were comparable to those reported in the literature. Additionally, the reaction medium along with the catalyst could be reused for up to 5 consecutive cycles without a significant loss in the reaction outcome. Several green metrics were calculated and compared to those of conventional procedures, revealing the advantages of using DESs.
PubMed: 38957114
DOI: 10.1002/cssc.202400911 -
Angewandte Chemie (International Ed. in... Jul 2024The alkylation of nucleophiles is among the most fundamental and well-developed transformations in chemistry. However, to achieve selective alkylation of complex...
The alkylation of nucleophiles is among the most fundamental and well-developed transformations in chemistry. However, to achieve selective alkylation of complex substrates remains a nontrivial task. We report herein a general and selective alkylation method without using strong acids, bases, or metals. In this method, the readily available phosphinites/phosphites, in combination with ethyl acrylate, function as effective alkylating agents. Various nucleophilic groups, including alcohols, phenols, carboxylic acids, imides, and thiols can be alkylated. This method can be applied in the late-stage alkylation of natural products and pharmaceutical agents, achieving chemo- and site-selective modification of complex substrates. Experimental studies indicate the relative reactivity of a nucleophile depends on its acidity and its steric environment. Mechanistic studies suggest the reaction pathway resembles that of the Arbuzov-Michalis reaction.
PubMed: 38957113
DOI: 10.1002/anie.202409931 -
Physical Chemistry Chemical Physics :... Jul 2024The discovery of novel two-dimensional (2D) half-metallic materials with a robust ferromagnetic (FM) order and a high Curie temperature () is attractive for the...
The discovery of novel two-dimensional (2D) half-metallic materials with a robust ferromagnetic (FM) order and a high Curie temperature () is attractive for the advancement of next-generation spintronic devices. Here, we propose a monolayer with stable 2D intrinsic FM half-metallicity, , the CrScTe monolayer, which was constructed by intercalating a monolayer of 1T-CrTe-type sandwiched between two layers of 2H-ScTe monolayers. Our calculations reveal that it exhibits exceptional dynamical, thermal, and mechanical stabilities accompanied by a robust half-metallicity characterized by a wide bandgap of 1.02 eV and FM ordering with a high of 326 K. Notably, these properties remain intact in almost the entire range of the biaxial strain from -5% to 5%. Furthermore, our investigations demonstrate excellent spin transport capabilities, including an outstanding spin-filtering effect, and a remarkably high tunneling magnetoresistance ratio peaking at 6087.07%. The remarkable magnetic features of the 2D CrScTe monolayer with room temperature FM, intrinsic half-metallicity, and 100% spin-polarization make it a promising candidate for the next-generation high-performance spintronic nanodevices as well as high-density magnetic recording and sensors.
PubMed: 38957083
DOI: 10.1039/d4cp01660b -
Journal of Cellular and Molecular... Jul 2024Pruritus is often accompanied with bacterial infections, but the underlying mechanism is not fully understood. Although previous studies revealed that...
Pruritus is often accompanied with bacterial infections, but the underlying mechanism is not fully understood. Although previous studies revealed that lipopolysaccharides (LPS) could directly activate TRPV4 channel and TRPV4 is involved in the generation of both acute itch and chronic itch, whether and how LPS affects TRPV4-mediated itch sensation remains unclear. Here, we showed that LPS-mediated TRPV4 sensitization exacerbated GSK101-induced scratching behaviour in mice. Moreover, this effect was compromised in TLR4-knockout mice, suggesting LPS acted through a TLR4-dependent mechanism. Mechanistically, LPS enhanced GSK101-evoked calcium influx in mouse ear skin cells and HEK293T cells transfected with TRPV4. Further, LPS sensitized TRPV4 channel through the intracellular TLR4-PI3K-AKT signalling. In summary, our study found a modulatory role of LPS in TRPV4 function and highlighted the TLR4-TRPV4 interaction in itch signal amplification.
Topics: TRPV Cation Channels; Animals; Toll-Like Receptor 4; Pruritus; Lipopolysaccharides; Humans; Signal Transduction; Mice; HEK293 Cells; Phosphatidylinositol 3-Kinases; Mice, Knockout; Mice, Inbred C57BL; Male; Calcium; Proto-Oncogene Proteins c-akt
PubMed: 38957035
DOI: 10.1111/jcmm.18509 -
Chemical Communications (Cambridge,... Jul 2024A mild and efficient electrochemical method for radical addition, cyclization, and migration reaction was described in this work. A difluoromethyl radical was produced...
A mild and efficient electrochemical method for radical addition, cyclization, and migration reaction was described in this work. A difluoromethyl radical was produced by anodizing CFHSONa. The resulting product was then added to olefin, underwent Smiles cyclization, and migrated to form β-difluoromethamide compounds after the release of SO. The process was free from metals and catalysts, gram-grade, and resistant to a variety of electron-rich substrates.
PubMed: 38957034
DOI: 10.1039/d4cc02543a -
Chemical Research in Toxicology Jul 2024Electronic cigarettes (ECs) emit many toxic substances, including metals, that can pose a threat to users and the environment. The toxicity of the emitted metals depends...
Electronic cigarettes (ECs) emit many toxic substances, including metals, that can pose a threat to users and the environment. The toxicity of the emitted metals depends on their oxidation states. Hence, this study examines the oxidation states of metals observed in EC aerosols. X-ray photoelectron spectroscopy analysis of the filters that collected EC aerosols identified the oxidation states of five primary metals (based on surface sample analysis), including chromium(III) (close to 100%) under low power setting while a noticeable amount of chromium(VI) (15%) at higher power settings of the EC, and copper(II) (100%), zinc(II) (100%), nickel(II) (100%), lead(II) (65%), and lead(IV) (35%) regardless of power settings. This observation indicates that the increased temperature due to higher power settings could alter the oxidation states of certain metals. We noted that many metals were in their lesser toxic states; however, inhaling these metals may still pose health risks.
PubMed: 38957009
DOI: 10.1021/acs.chemrestox.4c00033