Search Results (12,231)

This paper deals with the stability and decomposition of a recently predicted noble-gas compound, HXeNH₂. Despite natural progress and interest in noble-gas hydrides, little is known of their decomposition reaction. In this study, the dissociation reaction is explored by ab initio calculations and by Ab Initio Molecular Dynamics (AIMD) simulations. The results could be important for the future experimental search of the compound. It is found that the main decomposition channel is HXeNH₂ → H+Xe+NH₂. A key step in the reaction is found to be a rearrangement of the partial charges of the atoms involved. The results could be of significance also for reactions of other compounds with Xe-N chemical bond and other noble-gas hydrides. Full article

Advances in additive manufacturing have accelerated the development of 3D-printed dental resin composites. These materials contain a higher proportion of organic matrix and less filler than light-cured representatives, which may affect their behavior in the oral environment. This study aimed to evaluate the biological and chemical properties of 3D-printed dental resin composites before and after artificial aging, and to compare them with the light-cured representative. Specimens from a light-cured composite (Omnichroma—OMCR) and two 3D-printed composites (GT Temp PRINT—GTPR; SprintRay CROWN—SPRY) were subjected to aging treatments: unaged (T0) or thermocycled for 5000 (T1) and 10,000 cycles (T2). Biological evaluation was performed using MTT assay and Live/Dead cell fluorescence microscopy using human gingival fibroblasts, whereas Raman spectroscopy analysed materials’ structural changes. Materials exhibited good biocompatibility (>70% cell viability), with OMCR displaying greater variability. OMCR was more susceptible to chemical degradation under thermal stresses than both 3D-printed materials. Tested 3D-printed composites can provide comparable or even superior biological and chemical properties compared to light-cured representative, likely due to optimized resin formulations and post-curing protocols that improve polymer network organization and reduce residual monomer release. These findings support the potential of tested 3D-printed composites for manufacturing dental restorations. Full article

The operational stability of organic solar cells critically depends on the excited-state characteristics of electron acceptor materials. Through systematic quantum chemical calculations on four representative acceptors (PCBM, ITIC, Y6, and TBT-26), this study reveals fundamental spectra–stability relationships. Non-fullerene acceptors demonstrate superior light-harvesting with systematically tuned energy levels and significantly lower exciton binding energies (2.05–2.12 eV) compared to PCBM (2.97 eV), facilitating efficient charge separation. Structural dynamics analysis uncovers distinct stability mechanisms: ITIC maintains exceptional structural integrity (anionic RMSD = 0.023, S₁ RMSD = 0.134) with superior bond preservation, ensuring balanced performance–stability. Y6 exhibits substantial structural relaxation in excited states (S₁ RMSD = 0.307, T₁ RMSD = 0.262) despite its low exciton binding energy, indicating significant non-radiative losses. TBT-26 employs selective bond stabilization, preserving acceptor–proximal bonding despite considerable anionic flexibility. These findings establish that optimal molecular design requires both favorable electronic properties and structural preservation in photoactive states, providing crucial guidance for developing efficient and stable organic photovoltaics. Full article

Paraffin-based phase change materials (PCMs) have emerged as promising candidates for thermal energy storage (TES) applications due to their high latent heat, chemical stability, and low cost. However, their inherently low thermal conductivity and the risk of leakage during melting–solidification cycles significantly limit their practical performance. To address these limitations, numerous studies have investigated composite PCMs in which paraffin is incorporated into porous supporting matrices. Among these, diatomite has garnered particular attention due to its high porosity, large specific surface area, and chemical compatibility with organic materials. Serving as both a carrier and stabilizing shell, diatomite effectively suppresses leakage and enhances thermal conductivity, thereby improving the overall efficiency and reliability of the PCM. This review synthesizes recent research on paraffin–diatomite composites, with a focus on impregnation methods, surface modification techniques, and the influence of synthesis parameters on thermal performance and cyclic stability. The mechanisms of heat and mass transport within the composite structure are examined, alongside comparative analyses of paraffin–diatomite systems and other inorganic or polymeric supports. Particular emphasis is placed on applications in energy-efficient buildings, passive heating and cooling, and hybrid thermal storage systems. The review concludes that paraffin–diatomite composites present a promising avenue for stable, efficient, and sustainable phase change materials (PCMs). However, challenges such as the optimization of pore structure, long-term durability, and large-scale manufacturing must be addressed to facilitate their broader implementation in next-generation energy storage technologies. Full article

Conventional rubber-modified asphalt typically suffers from low rubber content and requires high construction temperatures. This study developed a warm-mix high-content crumb-rubber-modified asphalt (CRMA) with an increased rubber particle content of over 20%; moreover, the optimization of the warm-mixing agent was determined. Its rutting and cracking resistance performances were investigated using a dynamic shear rheometer (DSR) and a bending beam rheometer (BBR). Fourier Transform Infrared (FTIR) and Atomic Force Microscopy (AFM) were used to characterize the aging resistance and microstructural characteristics. The key findings revealed that the optimal dosage of the SDYK-type warm-mix additive (SDYK; a surfactant used to improve the high-temperature stability, low-temperature crack resistance, and anti-aging performance of asphalt) was 0.6% for high-rubber-content CRMA. The combination of warm-mix additives and rubber granules enhanced the aging resistance and elasticity of the asphalt while also contributing to an increase in chemical functional group indicators. The decrease in both the aliphatic chain index and branched alkane index of CRMA indicates that the warm-mix agent and the rubber additive enhanced the aging resistance of the asphalt. The warm-mix agent reduced the roughness of the asphalt, counteracting the roughness-enhancing effect of crumb rubber. This was attributed to the lubrication effect induced by the water film during the mixing process, which promotes a more uniform distribution of the rubber crumb network. This research established a theoretical and experimental basis for the application of high-rubber-content CRMA in large-temperature-difference regions. Full article

Spectral measurement technology has found extensive applications across a diverse range of fields, including chemical analysis, environmental monitoring, precise measurement, and laser frequency stabilization. However, the accuracy of spectral measurement results is often constrained by the power noise and frequency jitter inherent in the light source. In contrast to the traditional differential amplification method for acquiring spectral signals, our study introduces a novel approach. By employing a power correction quotient, we effectively suppress common-mode noise. Additionally, we introduce a novel composite differential method that, in theory, is capable of performing closed-loop processing on spectral signals to stabilize the laser frequency. This innovative method not only constructs a stable laser source but also yields high-quality spectral signals simultaneously. In an experiment involving iodine molecule absorption spectroscopy, the algorithm we propose demonstrated remarkable efficacy in mitigating distortions caused by modulated signals and significantly enhanced the signal-to-noise ratio. This algorithm is versatile and can be applied to the signal processing of any spectral signal sensor that employs dual-path light. Full article

To tackle the poor emulsibility of hydrophilic cellulose nanocrystals (CNCs), this study prepared octenyl succinic anhydride (OSA)-modified bamboo shoot CNC (OSNC) via acid hydrolysis and esterification, using microcrystalline cellulose (MCC) as a control. The degree of substitution (DS), chemical structure, crystalline structure, morphological characteristics, zeta potential, wettability, and thermal stability of OSNC and OSA-modified MCC (OSA-MCC) were characterized using multiple techniques. Results showed that at the optimal cellulose-to-OSA ratio (1:0.225), OSNC had a higher DS (0.029 ± 0.01) than OSA-MCC (0.024 ± 0.02). FTIR confirmed successful OSA grafting; XRD showed a preserved cellulose I crystal form with slightly reduced crystallinity; OSNC had improved dispersion stability (zeta potential: −44.0 mV), balanced amphiphilicity (contact angle: 61.8°), and enhanced thermal stability. This work enables high-value utilization of bamboo shoot by-products and supports developing green food-grade cellulose-based nanomaterials for food emulsions. Full article

In this study, we review the use of cyclodextrin-based formulations to develop oral tablets of cladribine by enhancing its bioavailability and to improve the solubility and stability of retrometabolic chemical delivery systems (CDSs) in general and estredox, a brain-targeting estradiol-CDS, in particular. Cyclodextrins (CDs), cyclic oligosaccharides that can form host–guest inclusion complexes with a variety of molecules, are widely utilized in pharmaceuticals to increase drug solubility, stability, bioavailability, etc. The stability of the complex depends on how well the guest fits within the cavity of the CD host; a model connecting this to the size of the guest molecules is briefly discussed. Modified CDs, and particularly 2-hydroxypropyl-β-cyclodextrin (HPβCD), provided dramatically increased water solubility and oxidative stability for estredox (estradiol-CDS, E₂-CDS), making its clinical development possible and highlighting the potential of our brain-targeted CDS approach for CNS-targeted delivery with minimal peripheral exposure. A unique HPβCD-based formulation also provided an innovative solution for the development of orally administrable cladribine. The corresponding complex dual CD-complex formed by an amorphous admixture of inclusion- and non-inclusion cladribine–HPβCD complexes led to the development of tablets that provide adequate oral bioavailability for cladribine, as demonstrated in both preclinical and clinical studies. Cladribine–HPβCD tablets (Mavenclad) offer a convenient, effective, and well-tolerated oral therapy for multiple sclerosis, achieving worldwide approval and significant clinical success. Overall, the developments summarized here underscore the importance of tailored cyclodextrin-based approaches for overcoming barriers in drug formulation for compounds with challenging physicochemical properties, and demonstrate the versatility and clinical impact of CD inclusion complexes in modern pharmaceutical development. Full article

The growing resistance of Tetranychus urticae to chemical pesticides highlights the need for alternative solutions for its sustainable control. To develop botanical acaricides and reduce the usage of chemical pesticides, this study assessed the acaricidal activity of AB extract and its combinations with four commercial insecticides: imidacloprid (IMI), acetamiprid (ACE), thiamethoxam (TMX), and bifenthrin (BF). Results showed that the AB extract suppressed detoxification enzymes and downregulated their corresponding genes in T. urticae. Bioassays identified hyoscyamine and genistein as key bioactive compounds. Field trials revealed that treatments with AB + IMI, AB + TMX, and AB + BF significantly enhanced the corrected efficacy against T. urticae compared with AB treatment, with the highest corrected efficacy observed for AB + BF. Notably, the AB + BF treatment did not influence the stability of the natural enemy community, as indicated by the characteristic indices of the natural enemy community, which suggests that the integration of AB extract with BF may represent a sustainable pest management strategy. Therefore, the AB extract represents an environmentally benign alternative to chemical pesticides for the sustainable control of T. urticae. Full article

Anthocyanins, a group of naturally occurring flavonoid compounds, have garnered increasing attention due to their wide-ranging biological activities that suggest their considerable potential to be utilized not only as natural food colorants but also as functional additives that can enhance food preservation and contribute to the development of health-promoting functional foods. Additionally, their sensitivity to environmental factors such as pH and temperature makes anthocyanins promising candidates for use in intelligent packaging systems, particularly as natural indicators for monitoring food freshness and quality throughout storage and distribution. Despite challenges related to their stability and regulatory acceptance, continued research into anthocyanins remains crucial for advancing sustainable, clean-label food technologies and reducing reliance on synthetic additives. To fully leverage their economic and health potential, it is essential to gain a comprehensive understanding of the various plant sources of anthocyanins, their chemical composition, extraction methods, and roles in different applications. Moreover, integrating anthocyanins into food and intelligent packaging systems presents various technical and regulatory challenges that are also summarized in this review. Full article

Andean berry (Vaccinium meridionale Swartz) is a species of berry mostly exclusive to the Andean ecosystems, mainly present in Colombia, Venezuela, Peru, and Jamaica, where it grows between 2000 and 3000 m.a.s.l. Although most of the fruit is harvested naturally, limited fruit production significantly restricts large-scale farming and sales. Most research on phytochemicals from this berry has focused on polyphenolic compounds, particularly anthocyanins such as cyanidin-3-O-galactoside and delphinidin-3-O-hexoside. These compounds have significant antioxidant potential and require appropriate post-harvest handling to preserve their stability and biological functionality. A systematic literature search was conducted covering studies from January 2000 to January 2025 across Scopus, PubMed, Web of Science, and Google Scholar. Evidence from original research includes chemical analyses, in vitro biological activity, in vivo effects in animal models, and clinical studies. Although findings suggest antiproliferative, chemoprotective, and cardioprotective properties, current evidence remains largely preclinical, and clinical validation is urgently needed. Despite its promise, challenges persist in standardizing cultivation, scaling production, and optimizing post-harvest. The berry has been incorporated into food products, but further research is essential to support its transition from experimental use to validated clinical applications. Full article

Antimicrobial peptides (AMPs), evolutionarily conserved components of the immune system, have attracted considerable attention as promising therapeutic candidates. Derived from diverse organisms, AMPs represent a heterogeneous class of molecules, typically cationic, which facilitates their initial electrostatic interaction with anionic microbial membranes. Unlike conventional single-target antibiotics, AMPs utilize rapid, multi-target mechanisms, primarily physical membrane disruption, which results in a significantly lower incidence of resistance emergence. Their broad-spectrum antimicrobial activity, capacity to modulate host immunity, and unique mechanisms of action make them inherently less susceptible to resistance compared with traditional antibiotics. Despite these advantages, the clinical translation of natural AMPs remains limited by several challenges, including poor in vivo stability, and potential cytotoxicity. Bioengineering technology offers innovative solutions to these limitations of AMPs. Two techniques have demonstrated promise: (i) a chimeric recombinant of AMPs with stable scaffold, such as human serum albumin and antibody Fc domain and (ii) chemical modification approaches, such as lipidation. This review provides a comprehensive overview of AMPs, highlighting their origins, structures, and mechanisms of antimicrobial activity, followed by recent advances in bioengineering platforms designed to overcome their therapeutic limitations. By integrating natural AMPs with bioengineering and nanotechnologies, AMPs may be developed into next-generation antibiotics. Full article

Organic field-effect transistors (OFETs) have emerged as a transformative platform for high-performance sensing technologies, yet their full potential can be realized only through coordinated performance optimization. This article provides a comprehensive review of recent strategies employed in polymer OFETs to enhance key parameters, including carrier mobility (μ), threshold voltage (Vth), on/off current ratio (I_on/I_off), and operational stability. These strategies encompass both physical and chemical approaches, such as annealing, self-assembled monolayers (SAMs), modification of main and side polymer chains, dielectric-layer engineering, buffer-layer insertion, and blending or doping techniques. The development of high-performance devices requires precise integration of physical processing and chemical design, alongside the anticipation of processing compatibility during the molecular design phase. This article further highlights the limitations of focusing solely on high mobility and advocates a balanced optimization across multiple dimensions—mobility, mechanical flexibility, environmental stability, and consistent functional performance. Adopting a multi-scale optimization framework spanning molecular, film, and device levels can substantially enhance the adaptability of OFETs for emerging applications such as flexible sensing, bioelectronic interfaces, and neuromorphic computing. Full article

Saturated and branched high molecular weight organic esters are highly valued as emollients in the cosmetic industry due to their superior properties. Their saturated character provides resistance to oxidation and rancidity. Additionally, their branched structure endows them with low melting temperatures, enabling them to remain liquid over a broad temperature range. These esters can be obtained from branched alcohols, branched fatty acids or both, using chemical or enzymatic processes. Among branched alcohols, Guerbet alcohols stand out. Due to their characteristic properties as branched, saturated alcohols with superior oxidative stability and extremely low volatility, they are proposed as excellent substrates for the enzymatic synthesis of these compounds. This study represents the first investigation into the biocatalytic synthesis of three specific esters: those formed between 2-octyl-1-dodecanol (C20 Guerbet alcohol) and the fatty acids myristic (MA), palmitic (PA), and stearic acid (SA). To achieve this, an environmentally sustainable biocatalytic process was developed. The synthesis involves a solvent-free esterification catalyzed by the commercial immobilized lipase, Lipozyme^® 435, conducted within a vertically stirred, thermostated batch tank reactor. Optimal conditions for lipase concentration and temperature were established, and the sustainability of the process was successfully quantified using various “green metrics”. Full article

Chlorobenzoic acids (CBAs) are a group of chlorinated persistent environmental pollutants with hard biodegradability, high water solubility, and well-documented carcinogenic and endocrine-disrupting properties. Electrocatalytic hydrodechlorination (ECH) is a highly efficient method under mild conditions without harmful by-products, but the ECH process commonly requires adding precious metal catalysts such as palladium (Pd). To address the economic constraints and more effective utilization of Pd, a palladium/manganese dioxide (Pd/MnO₂) composite catalyst was developed in this study by chemical deposition. This method utilized the excellent electrochemical activity of MnO₂ as a carrier as well as the hydrogen storage and activation capacity of Pd. The test showed the optimal Pd loading was 7.5%, and the removal percent of 2,4-dichlorobenzoic acid (2,4-DCBA), a typical CBA, reached 97.3% using 0.5 g/L of Pd/MnO₂ after 120 min of electrochemical reaction. Under these conditions, the dechlorination percent can also be as high as 89.6%. A higher current density enhanced the dechlorination efficiency but showed the lower current utilization efficiency. In practical applications, current density should be minimized on the premise of compliance with the water treatment requirement. Mechanistic studies showed that MnO₂ synergistically promoted hydrolysis dissociation and hydrogen spillover and facilitated Pd-mediated adsorption of atomic hydrogen (H*) for dehydrogenation of 2,4-DCBA. The presence of MnO₂ can effectively disperse the loaded Pd and reduce the amount of Pd via the above process. The catalyst exhibited excellent stability over multiple cycles, and the 2,4-DCBA removal could still reach more than 80% after the five cycles. This work establishes electrocatalytic strategies for effectively reducing Pd usage and maintaining high removal of typical CBAs to support CBA-related water treatment. Full article