This paper reveals how varying degrees of nanoparticle aggregation influence SERS enhancement, demonstrating the creation of economical and highly efficient SERS substrates using ADP, opening up significant application opportunities.
An erbium-doped fiber saturable absorber (SA), utilizing niobium aluminium carbide (Nb2AlC) nanomaterial, is reported to facilitate the generation of dissipative soliton mode-locked pulses. With the combination of polyvinyl alcohol (PVA) and Nb2AlC nanomaterial, stable mode-locked pulses, operating at 1530 nm with a repetition rate of 1 MHz and 6375 ps pulse widths, were created. The pump power of 17587 milliwatts yielded a measured peak pulse energy of 743 nanojoules. Besides offering beneficial design considerations for manufacturing SAs from MAX phase materials, this work exemplifies the significant potential of MAX phase materials for generating ultra-short laser pulses.
Bismuth selenide (Bi2Se3) nanoparticles, which are topological insulators, exhibit a photo-thermal effect due to the localized surface plasmon resonance (LSPR). Due to its peculiar topological surface state (TSS), the material exhibits plasmonic properties that make it suitable for use in medical diagnosis and therapy. The nanoparticles' application relies on a protective surface coating, a crucial step in preventing aggregation and dissolution within the physiological medium. The current study investigated the use of silica as a biocompatible coating for Bi2Se3 nanoparticles, a different approach from the common ethylene glycol method. This study demonstrates that ethylene glycol, as presented herein, is not biocompatible and alters the optical properties of TI. Employing a diverse range of silica layer thicknesses, the preparation of Bi2Se3 nanoparticles was successfully accomplished. In contrast to nanoparticles coated with a thick layer of 200 nanometers of silica, the optical characteristics of all other nanoparticles remained unchanged. RP-102124 In the context of photo-thermal conversion, silica-coated nanoparticles outperformed ethylene-glycol-coated nanoparticles, this improvement becoming more pronounced as the silica layer's thickness increased. A concentration of photo-thermal nanoparticles, 10 to 100 times lower, was crucial in reaching the desired temperatures. In vitro experiments on erythrocytes and HeLa cells found that silica-coated nanoparticles, in contrast to ethylene glycol-coated nanoparticles, are biocompatible.
By employing a radiator, a part of the heat produced by a car engine is taken away. Keeping pace with the ongoing advancements in engine technology proves challenging for both internal and external automotive cooling systems, requiring substantial effort to maintain efficient heat transfer. This work examined the heat transfer attributes of a novel hybrid nanofluid. A 40/60 blend of distilled water and ethylene glycol served as the suspending medium for the graphene nanoplatelets (GnP) and cellulose nanocrystals (CNC) nanoparticles, the primary constituents of the hybrid nanofluid. A counterflow radiator, in conjunction with a test rig configuration, was utilized to determine the thermal performance of the hybrid nanofluid. Based on the research findings, the GNP/CNC hybrid nanofluid proves more effective in improving the thermal efficiency of a vehicle's radiator. The suggested hybrid nanofluid led to a 5191% increase in convective heat transfer coefficient, a 4672% rise in overall heat transfer coefficient, and a 3406% enhancement in pressure drop, as compared to the distilled water base fluid. The radiator's potential for a better CHTC is achievable by using a 0.01% hybrid nanofluid within the optimized radiator tubes, this is determined through size reduction assessments, using computational fluid analysis. The radiator, equipped with a smaller tube and greater cooling capacity compared to typical coolants, results in a vehicle engine that occupies less space and weighs less. The graphene nanoplatelet/cellulose nanocrystal-based nanofluids, as hypothesized, exhibit enhanced heat transfer efficiency in automobiles.
Using a one-step polyol process, three types of hydrophilic and biocompatible polymers, namely poly(acrylic acid), poly(acrylic acid-co-maleic acid), and poly(methyl vinyl ether-alt-maleic acid), were attached to ultramicroscopic platinum nanoparticles (Pt-NPs). A study of their physicochemical properties and their X-ray attenuation characteristics was conducted. Platinum nanoparticles (Pt-NPs) coated with polymers displayed a consistent average particle diameter (davg) of 20 nanometers. Colloidal stability of polymers grafted onto Pt-NP surfaces remained exceptional (no precipitation observed for more than fifteen years after synthesis), and low cellular toxicity was consistently observed. At identical atomic concentrations and markedly higher number densities in aqueous media, polymer-coated platinum nanoparticles (Pt-NPs) displayed stronger X-ray attenuation than the commercial iodine contrast agent Ultravist, thus validating their potential as computed tomography contrast agents.
The application of slippery liquid-infused porous surfaces (SLIPS) to commercial materials yields a diverse array of functionalities, including the resistance to corrosion, improved heat transfer during condensation, anti-fouling properties, de/anti-icing characteristics, and inherent self-cleaning abilities. Pefluorinated lubricants, infused within fluorocarbon-coated porous structures, exhibited outstanding performance and remarkable durability; however, their inherent difficulty in degradation and the risk of bioaccumulation caused several safety concerns. Here we describe a new method for developing a lubricant-impregnated surface, utilizing edible oils and fatty acids. These compounds are safe for human use and readily break down in nature. RP-102124 Surface characteristics of anodized nanoporous stainless steel, enhanced by edible oil, reveal a substantially lower contact angle hysteresis and sliding angle, mirroring those of standard fluorocarbon lubricant-infused surfaces. Impregnation of the hydrophobic nanoporous oxide surface with edible oil blocks direct contact of the solid surface structure with external aqueous solutions. Stainless steel surfaces immersed in edible oils exhibit improved corrosion resistance, anti-biofouling properties, and condensation heat transfer due to the lubricating effect of the oils which causes de-wetting, and reduced ice adhesion is also a consequence.
Optoelectronic devices spanning the near to far infrared spectrum exhibit enhanced performance when ultrathin III-Sb layers are implemented as quantum wells or superlattices. In spite of this, these metal alloys experience significant surface segregation difficulties, thus creating major variations between their real forms and their theoretical models. By precisely inserting AlAs markers into the structure, ultrathin GaAsSb films (1 to 20 monolayers, MLs) were subjected to state-of-the-art transmission electron microscopy to meticulously observe the incorporation and segregation of Sb. Our detailed investigation empowers us to adopt the most effective model for portraying the segregation of III-Sb alloys (a three-layered kinetic model), reducing the number of adjustable parameters to a minimum. RP-102124 Analysis of the simulation results reveals a non-uniform segregation energy during growth, characterized by an exponential decay from 0.18 eV to asymptotically approach 0.05 eV; this dynamic is not considered in any of the existing segregation models. The phenomenon of Sb profiles following a sigmoidal growth model, with an initial lag of 5 ML in Sb incorporation, can be understood in light of a continuous change in surface reconstruction as the floating layer becomes richer.
Graphene-based materials' high light-to-heat conversion efficiency has made them a focal point in photothermal therapy research. Graphene quantum dots (GQDs), based on recent research, are predicted to possess advantageous photothermal properties, allowing for the facilitation of fluorescence image tracking across visible and near-infrared (NIR) wavelengths, outperforming other graphene-based materials in their biocompatibility metrics. Employing GQD structures, such as reduced graphene quantum dots (RGQDs), derived from reduced graphene oxide via top-down oxidation, and hyaluronic acid graphene quantum dots (HGQDs), hydrothermally synthesized from molecular hyaluronic acid, this study investigated these capabilities. GQDs' substantial near-infrared absorption and fluorescence throughout the visible and near-infrared spectral regions make them suitable for in vivo imaging, remaining biocompatible even at concentrations reaching 17 mg/mL. Low-power (0.9 W/cm2) 808 nm near-infrared laser irradiation of RGQDs and HGQDs in aqueous suspensions leads to a temperature elevation sufficient for cancer tumor ablation, reaching up to 47°C. Automated in vitro photothermal experiments, performed across multiple conditions in a 96-well plate, employed a simultaneous irradiation/measurement system. This system was custom-designed and constructed using 3D printing technology. Through the use of HGQDs and RGQDs, HeLa cancer cells were heated to 545°C, causing a substantial suppression of cell viability, from over 80% down to 229%. Fluorescence of GQD within the visible and near-infrared spectrum, indicative of its successful HeLa cell internalization, maximized at 20 hours, suggesting both extracellular and intracellular photothermal treatment capabilities. Photothermal and imaging modalities, when tested in vitro, demonstrate the prospective nature of the developed GQDs for cancer theragnostic applications.
The 1H-NMR relaxation properties of ultra-small iron-oxide-based magnetic nanoparticles were analyzed in relation to the application of various organic coatings. A first set of nanoparticles, with a magnetic core diameter ds1 of 44 07 nanometers, was coated with a mixture of polyacrylic acid (PAA) and dimercaptosuccinic acid (DMSA). The second set, exhibiting a larger core diameter, ds2, of 89 09 nanometers, received a coating of aminopropylphosphonic acid (APPA) and DMSA. Maintaining consistent core diameters, magnetization measurements revealed a comparable trend with temperature and field, regardless of the coating differences.