ABSTRACT A series of light emitting devices (LEDs) that consisted of a conjugated polymer poly [2‐methoxy‐5‐(2‐ethylhexyloxy)‐1,4‐phenylenevinylene] (MEH‐PPV) or blend of MEH‐PPV and CdSe/ZnS quantum dot (QD) emitting layer (EML), an electron‐transporting tris‐(8‐hydro‐xyquinoline)aluminum (Alq 3 ) layer and with/without a hole‐transporting poly( N , N ′‐bis(4‐butylphenyl)‐ N , N ′‐bis(phenyl)benzidine) (poly‐TPD) layer were fabricated and their operation characteristics were investigated. All the fabricated devices showed unnoticeably effect of QDs on electroluminescence spectra that originated from MEH‐PPV. However, the operation currents of LED devices that involved QDs in MEH‐PPV EML were significantly suppressed. This can be attributed to a large amount of charge confinement in QDs which limits current flow through the devices.
ABSTRACT Skin protection from ultraviolet (UV) radiation is a contemporary process that requires constant updates and development. Although conventional UV filters are effective and widely used, there are still many shortcomings that need to be thoroughly overcome. The usage of nature‐derived UV filters, in particular natural extracts, is promised to be a safe and environmentally friendly solution to tackle these shortcomings. The role of natural extracts in absorbing UV and neutralizing free radicals to protect the skin from UV radiation is discussed in this review. In addition, the combination of traditional UV filters and natural extracts is considered. Overall, using natural UV filters is expected to not only provide skin protection but also bring long‐term benefits to the health and beauty of the skin.
Capsicum has been commonly employed for numerous therapeutic purposes besides its use as a food additive. The alkaloids called capsaicinoids are recognized as being responsible for medical applications. In this study, the effects of drying methods and extraction conditions for capsaicin were investigated on commercial Capsicum annuum L. cultivated in An Giang, Dong Thap, and Vinh Long provinces. The qualitative analysis was carried out using thin-layer chromatography and high-performance liquid chromatography for the detection of capsaicin. The obtained extract showed inhibition activity against Staphylococcus aureus, while the massage products inherited the beautiful natural orange color from red peppers: the massage gel had a thin and light texture that feels cool and did not cause stickiness to the skin, was transparent with the scent of lemongrass essential oil; the cool thick massage cream that did not cause oily or sticky skin with the scent of cinnamon essential oil; the massage gel-cream had a thin, light texture and was cool when applied to the skin with the scent of peppermint essential oil. These products were evaluated to meet quality standards of sensory, pH, consistency, functionality, microorganisms, and durability.
ABSTRACT Nanomaterials have demonstrated significant potential in the coating industry, particularly for enhancing polyurethane (PU) coatings used in the automotive, aerospace, marine, and construction sectors. Despite their versatility, PU coatings frequently struggle to maintain corrosion and UV radiation resistance, leading to premature deterioration and reduced longevity. The integration of nanoparticles into the PU matrix can enhance performance, improving corrosion resistance, UV absorption, and overall durability. Nanoparticles such as ZnO, TiO 2 , SiO 2 , carbon nanotubes, and nanoclay form compact networks that effectively withstand corrosive substances and UV radiation. Furthermore, these additives improve mechanical properties, such as hardness and adhesion, and can be tailored to specific applications. This review focuses on the application of cerium‐based nanomaterials, highlighting their superior UV‐blocking capabilities and active stabilization mechanisms compared to traditional metal oxides. Utilizing these nanomaterials offers the dual advantage of minimizing maintenance requirements and decreasing waste production, thereby benefiting the environment.
ABSTRACT Schiff bases, particularly those containing sulfonamide (─SO 2 NH─) groups, have gained attention for their diverse applications in coordination chemistry and pharmaceuticals. This study presents the synthesis and crystallographic characterization of a novel Schiff base, 4‐((2‐hydroxy‐3‐methoxybenzylidene)amino)‐ N ‐(pyridin‐2‐yl)benzenesulfonamide. The compound was synthesized through a condensation reaction and crystallized into high‐quality single crystals, enabling precise structural determination via single‐crystal X‐ray diffraction (SC‐XRD). The compound adopts a monoclinic P 2 1 / n space group, stabilized by extensive hydrogen bonding (N─H···O and O─H···N) and π‐π stacking interactions, which contribute to its molecular stability and potential coordination properties. Spectroscopic techniques, including FT‐IR, UV–vis, and NMR, confirmed the molecular structure, while density functional theory calculations provided insights into its electronic properties, revealing a narrow HOMO–LUMO energy gap indicative of charge‐transfer capabilities. Additionally, Hirshfeld surface analysis highlighted the role of hydrogen bonding and van der Waals forces in crystal stabilization. The findings underscore the significance of Schiff base compounds in the design of advanced materials and pharmaceuticals, with potential applications in coordination chemistry and drug development.
Chitin is a valuable bioresource, a sustainable biomaterial that is obtained from marine shell wastes. Chitin has been utilized in various diverse applications, cutting edges across human, societal, and environmental benefits. From chitin, numerous other derivatives have been derived, extrapolating the utility of this sustainable material. Voluminous research publications exist concerning chitosan and its derivatives, but very few are available that exclusively deal with chitin and its applications. Chitin nanocomposites helped overcome the inherent limitations of chitin, predominantly its bioavailability. The present review specifically reviews the contributions of chitin nanocomposites/metal nanocomposites for biomedical applications. With chitosan and the other derivatives being projected predominantly for drug delivery applications, this review presents a streamlined targeted survey on the milestones achieved by chitin nanocomposites and metal nanocomposites. A comparison between chitin and chitosan metal nanocomposites in drug delivery applications has also been presented and inferences discussed. The dearth in availability of prominent research studies for chitin nanocomposites as well as their corresponding metal nanocomposites, has been highlighted. The fact that the potential of chitin, nanoforms, and nano‐metal composites are being undermined, because of inadequate research evidence, which has led to preliminary conclusions, has also been discussed.
This review provides an overview of the fundamental characteristics of Ti 3 C 2 T x MXene and its applications in energy storage and conversion technologies. Initially investigated in 2011, Ti 3 C 2 T x MXene has garnered attention due to its distinctive properties, which render it particularly advantageous for a range of electrochemical applications. Notably, Ti 3 C 2 T x MXene has exhibited considerable efficacy in corrosion‐resistant coatings, offering substantial protection in various toxic environments. Its exceptional attributes, including high electrical conductivity and tunability, establish Ti 3 C 2 T x MXene as a promising candidate for use as an electrocatalyst in lithium‐ion, sodium‐ion, and potassium batteries. This review aims to present the most recent findings, advancements, and future perspectives regarding the role of Ti 3 C 2 T x ‐based composites in energy storage applications.
In this study, a simple method involving immersion and heat treatment was used to modify graphite felt, enabling the attachment of Co 3 O 4 and altering its morphology. The etching process created nanorod structures, which significantly increased the surface area and improved wettability. A Co(NO 3 ) 2 concentration of 4 m m demonstrated optimal electrochemical activity compared to pristine graphite felt. Following the modification, the electrochemically active surface area reached a high value of 131.71 cm 2 , the charge transfer resistance decreased to 12.27 Ω, and the exchange current density increased to 25.02 mA/cm 2 . Cyclic voltammetry measurements revealed that GF4 exhibited reversible redox activity across various scan rates and maintained stability over 50 cycles at a scan rate of 1.0 mV/s, with I pa / I pc = 1.18 and ∆ E p = 220 mV. These findings indicate that the modification method improves the performance of graphite felt cathodes in vanadium redox flow batteries, emphasizing its potential for energy storage.
Environment‐friendly reactions in organic synthesis have a special and inimitable position. Regarding more ecological and sustainable methods for different organic transformations, there has been notable advancement in the past. In this regard, magnetic nanoparticles draw a lot of interest within the framework of green synthesis. MNPs have been applied as a green catalyst in green synthesis to produce several heterocycles. Oxazole is regarded as a popular and quite useful motif among aza‐heterocycles. It offered various lead structures for the development of drug candidates. Using MNPs as a green catalyst increases the demand for the development of oxazole based molecular architectures. Therefore, it is indeed a future demand to develop more and more derivatives of oxazole via green synthetic methodology. Thus, this work provides a first report (from 2015 to present) on the function of green catalysts as MNPs in producing a wide range of privileged oxazole derivatives.
In this study, cuminaldehyde and chitosan coating were used to inhibit melanosis formation and prolong the shelf life of black tiger shrimp stored at 0 degrees C. Four treatments including the control, 0.5% cuminaldehyde solution, 2% chitosan, and the combination of 0.5% cuminaldehyde and 2% chitosan solution were performed. Sensory, chemical, and microbiological analyses were used to evaluate the effectiveness of treatments during 17 days of storage. Melanosis scores, histamine, TMA-N, TVB-N indexes, and total visible count (TVC) were also measured. The results show that there is a correlation between TVC and melanosis score. Melanosis scores in treated samples were lower than those in control during storage. Melanosis score was approximately 6 on day 8 for control samples, day 13 for cuminaldehyde group, day 11 for chitosan samples, and day 15 for cuminaldehyde/chitosan samples. This is also the time when the TVC value of samples reached the log cfu/g threshold approximately 6, except for the cuminaldehyde samples with TVC value = 6.37. The concentration of TVB-N, TMA-N, and histamine gradually increased for all samples, while shrimp quality decreased with storage time. The regression equation between chemical indices and melanosis score was built on each sample group (R 2 = 0.990). The combination of 0.5% cuminaldehyde and 2% chitosan treatment showed the high effectiveness in inhibiting melanosis formation and extending shelf life of shrimp compared to other treatments. The cuminaldehyde and chitosan combined treatment maintained the shrimp quality till 15 days, beyond the shelf life achieved with other evaluated applications.
The study aimed to investigate the potential of cashew (Anacardium occidentale L.) flesh as a tannin-based mordant for cellulosic dyeing. Herein, cotton was dyed with turmeric ethanol extracts in combination with cashew apple juice. The highest curcumin exhaustion (approximate to 87%) was obtained after 60 min of dyeing at 70 degrees C, with a liquor ratio of 1:50 and 30 g/L of Na2SO4. The incorporation of cashew juice was proven to enhance fixation and improve the washing fastness of the dyed fabric from grade 2-3 to 3. The product, after being treated with eco-friendly KAl(SO4)2 mordant, exhibited high washing fastness, with a rating of 4-5, comparable to that of synthetic dyes. Additionally, the strong antimicrobial capacity of cashew juice against Staphylococcus aureus and Escherichia coli enhanced the fabric's antibacterial potential, boosting the product's functional attributes. A quantitative test (AATCC 100) showed a significant reduction in bacterial count after 18 h: 73.68% for S. aureus and 85.71% for E. coli. Unfortunately, the lightfastness assessment of the fabric only reached grade 1, indicating that the combination of tannin and metal ions could not help improve curcumin's intrinsically high sensitivity to light. Overall, this study suggests that cashew apples could serve as an effective green mordant for natural dyeing, showcasing the prospect to utilize this valuable agri-food waste.
Peptidomimetics incorporating rigid scaffolds represent a promising strategy for enhancing the metabolic stability and receptor selectivity of neuropeptide analogs. This study describes the synthesis and receptor activation assay of five helicokinin analogs (4, 9, 12, 24, and 28) containing a spiro-oxindole piperidine (SIP) scaffold. Replacement of the Pro-Trp dipeptide in analog 4 led to a complete loss of activity (EC50 > 100 & micro;m), highlighting its essential role in receptor recognition. In contrast, substitution of the Tyr residue with the SIP scaffold in analog 28 retained full activity (EC50 = 0.003 & micro;m), indicating that the Tyr residue is not essential for receptor binding in this analog series. Other analogs (9, 12, and 24) exhibited intermediate activity, reflecting position-dependent effects of backbone rigidification. Density functional theory (DFT) calculations at the B3LYP/6-31G(d,p) level, combined with non-covalent interaction analysis, revealed that peptide 28 adopts a favorable turn-like geometry, stabilizing hydrogen bonds and van der Waals interactions, whereas inactive analogs displayed disrupted electronic delocalization and larger HOMO-LUMO energy gaps, as inferred from DFT analysis. These findings demonstrate the utility of spirocyclic scaffold for fine-tuning bioactive conformations in insect neuropeptide mimetics.
Schiff bases, particularly those containing sulfonamide (& horbar;SO2NH & horbar;) groups, have gained attention for their diverse applications in coordination chemistry and pharmaceuticals. This study presents the synthesis and crystallographic characterization of a novel Schiff base, 4-((2-hydroxy-3-methoxybenzylidene)amino)-N-(pyridin-2-yl)benzenesulfonamide. The compound was synthesized through a condensation reaction and crystallized into high-quality single crystals, enabling precise structural determination via single-crystal X-ray diffraction (SC-XRD). The compound adopts a monoclinic P21/n space group, stabilized by extensive hydrogen bonding (N & horbar;H & centerdot;& centerdot;& centerdot;O and O & horbar;H & centerdot;& centerdot;& centerdot;N) and pi-pi stacking interactions, which contribute to its molecular stability and potential coordination properties. Spectroscopic techniques, including FT-IR, UV-vis, and NMR, confirmed the molecular structure, while density functional theory calculations provided insights into its electronic properties, revealing a narrow HOMO-LUMO energy gap indicative of charge-transfer capabilities. Additionally, Hirshfeld surface analysis highlighted the role of hydrogen bonding and van der Waals forces in crystal stabilization. The findings underscore the significance of Schiff base compounds in the design of advanced materials and pharmaceuticals, with potential applications in coordination chemistry and drug development.
In this study, a series of novel bis-1,2,3-triazole-linked pyrimidinone hybrids were rationally designed and synthesized via tosylation reaction, Hantzsch reaction, and nucleophilic substitution, followed by Copper-catalyzed azide-alkyne cycloaddition (CuAAC) reactions, highlighting an environmentally sustainable and cost-effective approach. The synthesized compounds were characterized through comprehensive analytical techniques, including nuclear magnetic resonance spectroscopy (1H/13C) and high-resolution mass spectrometry analysis. The compounds were assessed for anticancer activity using the MTT assay against the human lung (NCI-H69, A549), colon (HCT116), and breast cancer cell lines (T47D and MCF7). Key derivatives (8g and 8i) showed significant activity on the NCI-H69 and MCF7 cell lines with IC50 values of 5.14 +/- 0.76, 4.63 +/- 0.64, 5.50 +/- 0.73, and 6.09 +/- 0.99 & micro;M, respectively, comparable to the standard drug, and are nontoxic at their effective concentration as anticancer agents. Molecular docking studies were also conducted to assess the interaction profile of the active synthesized triazole hybrids with the human lung cytochrome P450 2A13 target receptor (PDB: 2P85). It was found through docking studies that the synthesized bis-triazole hybrids (8c, 8f, 8g, and 8i) might interact with several amino acids, with binding energies of -6.25, -5.83, -6.80, and -6.40 kcal mol-1, respectively. Drug likeness of the leading compounds was also evaluated through absorption, distribution, metabolism, excretion, and toxicity analysis.
This study delves into the intricate design and functionality of xylan/cellulose (X/C) nanocomposites enhanced with glutaraldehyde and Tween-80, uncovering the critical relationships between their composition, structure, and multifaceted properties. By systematically varying the proportions of xylan, cellulose, glutaraldehyde, and Tween-80, we observed significant impacts on the composites' physical, chemical, and biological attributes. Fourier transform infrared (FTIR) spectroscopy highlighted esterification (1740-1750 cm-1) and ether (1100-1200 cm-1) peaks in Tween-80 modified samples, with Schiff base formation (C & boxH;N stretching at similar to 1620-1650 cm-1) in glutaraldehyde-rich nanocomposites. X-ray diffraction (XRD) analysis revealed the highest crystallinity index (48.2%) in X/C-3, attributed to balanced xylan-cellulose proportions, and the lowest (36.4%) in X/C-2 due to xylan induced amorphization. Corrosponding d-values ranged from 3.31296 & Aring; (X/C-1) to 4.16839 & Aring; (X/C-2). Scanning electron microscopy (SEM) provided a window into anatomy of surfaces, showcasing influence of component ratios and additives on composite homogeneity. Electro-kinetic potential measurements underscored the colloidal stability in X/C-2 (-17.06 mV) and the lowest in X/C-5 (-12.61 mV) due to glutaraldehyde crosslinking. Particle size distribution (D50) ranged from 162.5 nm (X/C-5) to 304.2 nm (X/C-4), correlating with composition and crosslinking density. Antioxidant activity ranged from 68.5% to 84.7%, while antibacterial assays confirmed potency in favor of both Gram-positive as well as Gram-negative bacteria. This research highlights the pivotal role of composition in fine-tuning the physical, chemical, and biological properties of X/C nanocomposites, offering avenues for their application in biomedical, pharmaceutical, and environmental contexts.
Phosphogypsum (PG), a byproduct of fertilizer production in Vietnam, is predominantly landfilled, posing significant environmental challenges. This study investigates PG as a reinforcing filler for epoxy resin composites with contents of 0, 3, 6, and 9 wt%. Comprehensive characterization using infrared spectroscopy (IR), thermogravimetric analysis (TGA), mechanical testing, and scanning electron microscopy (SEM) was conducted. Results confirmed that PG did not chemically react with the epoxy matrix but contributed to enhanced thermal stability. Mechanical properties showed slight reductions in tensile and izod impact strength, whereas flexural strength and fracture toughness improved considerably. The optimal performance was observed at 6 wt% PG, where flexural strength increased from 79.5 to 118.2 MPa and fracture toughness from 1.8 to 2.0 MPa m(1/2). SEM analysis revealed porous PG particles (< 39.5 & micro;m) dispersed in an epoxy matrix and rougher, zigzag fracture surfaces, indicating resistance to crack propagation pathways. Overall, PG demonstrates promise as a sustainable, low-cost filler for epoxy composites, offering both performance enhancement and an effective approach to reduce industrial waste disposal.
A concise microwave-assisted protocol has been established for the efficient synthesis of novel alpha,beta-unsaturated ketones bearing a pyrano[2,3-f]chromene-4,8-dione core. The pivotal intermediate, 3-acetyl-2,10-dimethyl-4H,8H-pyrano[2,3-f]chromene-4,8-dione, was obtained in 78% yield via a Kostanecki-Robinson reaction and subsequently transformed into a series of thirteen derivatives (5a-5m) through Claisen-Schmidt condensations with aromatic aldehydes, providing the target compounds in high isolated yields (74%-94%) within 10 min under optimized microwave conditions. Structural identities of all compounds were unambiguously confirmed by comprehensive spectroscopic analyses. Preliminary antioxidant evaluation employing the DPPH radical scavenging assay indicated that phenolic substitution plays a critical role in activity. Among the series, the vanillin-derived analogue 5e exhibited the highest inhibition (88.4% at 50 & micro;M), approaching the potency of ascorbic acid (97.6%). Collectively, these results establish a rapid and sustainable synthetic methodology and underscore the potential of this scaffold as a promising antioxidant chemotype. Nevertheless, the biological findings should be regarded as preliminary, warranting further systematic investigation.
This study investigates the feasibility of valorizing spent coffee grounds (SCG) as a sustainable bio-adsorbent for the removal of hexavalent chromium (Cr(VI)) from aqueous solutions through a simple Ca(OH)2-assisted modification. Unlike conventional adsorbents that often require high-temperature carbonization or aggressive chemical activation, the proposed approach employs a low-cost, low-temperature, and environmentally benign treatment to enhance the adsorption performance of SCG. The modified materials were prepared via washing, drying, sieving, and Ca(OH)2 treatment at different concentrations, followed by systematic adsorption experiments under various conditions of contact time, pH, adsorbent dosage, temperature, and initial Cr(VI) concentration. The results indicate that Ca(OH)2 treatment effectively improves the physicochemical properties of SCG by increasing surface reactivity and the availability of active adsorption sites. Under optimal conditions (contact time 180 min, pH 3, adsorbent dosage 1 g, and temperature of 313K), the modified SCG achieved a maximum adsorption capacity of 19.84 mg g-1. Regeneration studies showed that HNO3 was the most effective desorbing agent, with a desorption efficiency of 91.60%, although a gradual decline in adsorption efficiency was observed over successive reuse cycles. Overall, this work demonstrates a practical and sustainable strategy for converting waste coffee grounds into functional adsorbents, highlighting the potential of Ca(OH)2-assisted modification as a scalable and eco-friendly route for Cr(VI) removal and wastewater remediation.
Numerous methods involving reducing and stabilizing agents were applied in the past to produce silver nanoparticles (AgNPs) rapidly. However, these reducing agents are unsafe thus using a green approach over chemical techniques is a need for today as they are ecofriendly, low-cost, sustainable, and biocompatible. Therefore, the AgNPs were produced using Aspergillus fumigatus BTCC10 (KY486782) by addition of various reducing and capping agents like ethylene diamine tetra acetic acid, glucose, polyethylene glycol, ammonium sulfate, glycine, and cellulase. These common agents were added to the extract and their effects were examined on the morphology of the nanoparticles (NPs). AgNPs with varying shapes and sizes were formed from spherical to irregular shape which were later confirmed by atomic force microscopy; whereas the size of NPs produced fluctuated from 33.45 to 255.7 nm. The absorption peaks were detected between 398 and 465 nm for these added reducing and enhancing agents verifying the establishment of NPs. The results showed that AgNPs by the supplementation of cellulase (5%) developed the smallest sized nanoparticles (33.45 +/- 0.08 nm) without aggregation with zeta potential of -7.40 mV along with X-ray diffraction studies authenticating its crystalline characteristics that is significant. Henceforth its antibacterial activity was analyzed against Pseudomonas aeruginosa (BTCB01), Staphylococcus aureus (BTCB02), and Escherichia coli (BTCB03) through disc diffusion method. Later, zone of inhibition was evaluated against E. coli at 24 +/- 0.30 mm which is noteworthy. The NPs demonstrated effective antibacterial activity with microbes that can benefit many sectors like pharmaceutical, textile, food and cosmetics in future. In the end, the yield (%) of the generated AgNPs was also calculated and the sample with addition of cellulase contributed towards a maximum yield of 52.6 +/- 1.08% that is unique.
This study thoroughly investigated the electronic structure properties and topological analysis of the triphenylamine-substituted dithienopyrrole oligomer DTP-TPA, which shows great promise for organic photovoltaic devices. The molecule's structure and attributes were accurately predicted through density functional theory calculations using the B3LYP functional and cc-pVDZ basis set. This molecule exhibits a large dipole moment of 4.291711 Debye and a high polarizability value of 1087.331000 a.u. These characteristics indicate that it can efficiently transport charges and undergo significant deformation of the electron cloud when exposed to external electric fields. As a result, DTP-TPA is well-suited for applications in optoelectronics and nonlinear optics. The molecule's charge transfer resistance, polarizability, and electron-accepting or -donating tendencies were elucidated by computing global reactivity descriptors such as hardness, softness, chemical potential, electronegativity, and electrophilicity/nucleophilicity indices. The electrostatic potential maps show areas of positive charge around the sulfur atoms in the dithieno[3,2-b;2,3-d] pyrrole core, while the nitrogen atoms in the N,N-diphenylamino substituents exhibit areas of negative charge. The electron localization function and localized orbital locator maps offer valuable insights into the electronic structure and bonding characteristics. Additionally, the average localized ionization energy map sheds light on the electron-donating nature of the substituents and the impact of the conjugated backbone on ionization energies. The analysis of noncovalent interactions revealed the existence of van der Waals and steric interactions within the molecule, indicating the possibility of organized structures and sleek surface morphologies, as confirmed by atomic force microscopy analysis.
