Guided flows in coronal magnetic flux tubes

There is evidence for coronal plasma flows to break down into fragments and to be laminar. We investigate this effect by modeling flows confined along magnetic channels. We consider a full MHD model of a solar atmosphere box with a dipole magnetic field. We compare the propagation of a cylindrical flow perfectly aligned to the field to that of another one with a slight misalignment. We assume a flow speed of 200 km/s, and an ambient magnetic field of 30 G. We find that while the aligned flow maintains its cylindrical symmetry while it travels along the magnetic tube, the misaligned one is rapidly squashed on one side, becoming laminar and eventually fragmented because of the interaction and backreaction of the magnetic field. This model could explain an observation of erupted fragments that fall back as thin and elongated strands and end up onto the solar surface in a hedge-like configuration, made by the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory. The initial alignment of plasma flow plays an important role in determining the possible laminar structure and fragmentation of flows while they travel along magnetic channels.Comment: 11 pages, 8 figures, accepted for publication, movies available upon request to the first autho

Magnetically Mediated Vortexlike Assembly of Gold Nanoshells

Gold nanoshells currently attract increasing research interests due to the important role in many subjects. For practical applications, random arrangement of the nanoparticles is often unfavored so that the assembly of gold nanoshells is becoming a central issue. We here proposed to utilize time-variant magnetic field to direct the assembly of gold nanoshells. It was discovered that the alternating magnetic field can mediate the vortex-like assembly of gold nanoshells. The mechanism was explored and thought to be relative with the electric field of induction which caused the thermal gradient on the substrate and the electric force. The vortexlike structure as well as the assembly mechanism will play an important role in research and application of gold nanomaterials

Magnetically Mediated Vortexlike Assembly of Gold Nanoshells

Gold nanoshells currently attract increasing research interests due to the important role in many subjects. For practical applications, random arrangement of the nanoparticles is often unfavored so that the assembly of gold nanoshells is becoming a central issue. We here proposed to utilize time-variant magnetic field to direct the assembly of gold nanoshells. It was discovered that the alternating magnetic field can mediate the vortex-like assembly of gold nanoshells. The mechanism was explored and thought to be relative with the electric field of induction which caused the thermal gradient on the substrate and the electric force. The vortexlike structure as well as the assembly mechanism will play an important role in research and application of gold nanomaterials

Integrated Hierarchical Inorganic Support Ionic Liquid Membrane for Scalable Utilization of CO₂

Developing a scalable and modular combination of known technologies to construct defect-free ionic liquid membranes for CO2 capture and utilization is a sustainable chemical process requirement, instead of traditional membranes with a trade-off between permeability and selectivity. Herein, we report Bmim Cl supported on surface nanochannel tubular ceramic tubes by rapid thermal deposition and vacuum suction and fabricated high specific surface area membranes enabling thermocatalytic CO2 cycloaddition reaction with propylene oxide in a membrane reactor. The Bmim Cl membrane infiltrated the confined pores at a depth of about 85.58 μm and precisely accommodated a sufficient amount of active sites combined with the porous overcoating, which helps to mediate the reaction. Also, the optimization of different feeding modes was carried out by a quantitative comparison of continuous membrane catalysis and identification of surmountable obstacles, such as possible accumulation of high-boiling products and membrane stability, and different test conditions were evaluated to determine the critical influencing factors. This work may stimulate innovative energy-efficient integration techniques and design paradigms for advanced membranes

Controllable Preparation of Core–Shell Au–Ag Nanoshuttles with Improved Refractive Index Sensitivity and SERS Activity

Recent studies have conclusively shown that the plasmonic performance of Au nanostructures can be enhanced by incorporating Ag. Here, we developed a simple and robust approach for preparing core–shell Au–Ag nanoshuttles (NSs) using single-crystal Au nanorods (NRs) as cores. Upon tailoring the temperature of the reaction system containing alkaline glycine buffer (pH 8.5), exceptionally monodisperse Au–Ag NSs with sharp tips and tunable shell thickness could be routinely achieved in high yield through an epitaxial growth process. In particular, high-resolution transmission electron microscopy and nitric acid corrosive experiments revealed that the shells of these NSs consisted of a homogeneous Au–Ag alloy, rather than pure Ag or Au as previously reported. It was found that glycine played an important role in determining the final metal contents of the shell by regulating the reduction kinetics. In addition, the obatined Au–Ag NSs with sharp tips were shown to have significantly improved refractive index sensitivity and surface-enhanced Raman scattering activity relative to the original Au NRs, making these materials promising for biomedical applications, such as biosensing and biolabeling

DataSheet1_Endowing improved osteogenic activities with collagen membrane by incorporating biocompatible iron oxide nanoparticles.docx

Introduction: Collagen-based scaffolds, renowned for their exceptional biocompatibility, have garnered attention as promising scaffolds for advancing bone tissue regeneration. Nevertheless, these scaffolds possess inherent limitations, such as notably compromised osteo-conductivity and osteo-inductivity.Methods: Our study focused on enhancing the mechanical properties and osteogenic bioactivities of bovine-derived collagen membranes (CMs) from the Achilles tendon by incorporating FDA-approved iron oxide nanoparticles (IONPs), termed as IONP-CM. Three types of IONP-CMs (IONP-CM-0.5, IONP-CM-1, and IONPCM-1.5) were constructed by altering the amounts of feeding IONPs.Results: Surface topography analysis demonstrated comparable characteristics between the IONP-CM and neat CM, with the former exhibiting augmented mechanical properties. In vitro evaluations revealed the remarkable biocompatibility of IONP-CMs toward mouse calvarial pre-osteoblast MC3T3-E1 cells, concurrently stimulating osteogenic differentiation. Mechanistic investigations unveiled that the osteogenic differentiation induced by IONP-CMs stemmed from the activation of the Wnt/β-catenin signaling pathway. Furthermore, in vivo bone regeneration assessment was performed by implanting IONP-CMs into the radial defect in rabbits. Results derived from micro-computed tomography and histological analyses unequivocally substantiated the capacity of IONP-CMs to expedite bone repair processes.Discussion: IONP-CMs emerged as scaffolds boasting exceptional biocompatibility and enhanced osteogenic properties, positioning them as promising candidates for facilitating bone tissue regeneration.</p

Microstructure and Flight Behaviors of Droplet and its Solidification in Twin-Wire Arc Sprayed Ni-Al Composite Coatings

<div><p>Droplet flight and solidification behaviors during twin-wire arc sprayed (TWAS) composite coatings were systematically investigated. Both theoretical model and numerical method were established for calculating the droplet deformation, breakup and solidification process in air flow based on the volume of fluid (VOF) dual-phase flow model jointed with the standard k-ε model. The experimental simulation results indicate that TWAS droplet is broken through explosion or two steps breaking process. The calculation of TWAS gas flight dynamics demonstrates that the TWAS particles are accelerated at first and then slowed down. Microstructure of the TWAS prepared Ni-5wt.%Al and Ni-20wt.%Al composite coating was accordingly characterized by XRD, SEM and TEM, so the phase compositions of the Ni-Al composite coatings were obtained. TEM analysis also showed that an amorphous phase was formed according to the characteristic of diffraction ring in Ni matrix solid solution at an original state.</p></div

Variations of precipitation and soil temperature (5 cm depth) in the study area during the sampling periods.

<p>Variations of precipitation and soil temperature (5 cm depth) in the study area during the sampling periods.</p

Pearson's correlation coefficients between N₂O fluxes and soil characteristics.

<p>WFPS: water-filled pore space. T: temperature. M: moisture. * represents significant correlation at p = 0.05.</p

Fabrication of Hydrogel with Cell Adhesive Micropatterns for Mimicking the Oriented Tumor-Associated Extracellular Matrix

For mimicking the fibrous extracellular matrix (ECM), a facile method for patterning anticell adhesive substrate was novelly applied on agarose hydrogel. Without using masks or templates for etching, we applied the magnetic field-induced colloidal assembly of magnetic nanoparticles on the flat agarose hydrogel to form cell-adhesive micropatterns. Meanwhile, tuning the hydrogel substrate’s modulus to fit real tissue was experimentally demonstrated. Magnetic nanobeads were also assembled on this hydrogel surface and formed more complete and regular patterns. The patterned hydrogel substrate could actually influence behaviors of different cancer cells, including adhesion, growth, and migration