Unexpected Magnetic Moments in Manganese-Doped (CdSe) Nanoclusters: Role of Ligands.

This study explores the enhancement in magnetic and photoluminescence properties of Mn-doped (CdSe) nanoclusters, significantly influenced by the introduction of paramagnetic centers through doping, facilitated by optimized precursor chemistry and precisely controlled surface ligand interactions. Using a cost-effective and scalable synthesis approach with elemental Se and NaBH (Se-NaBH) in n-octylamine, we tailored bonding configurations (Cd-O, Cd-N, and Cd-Se) on the surface of nanoclusters, as confirmed by EXAFS analysis. These bonding configurations allowed for tunable Mn-doping with tetrahedral coordination, further stabilized by hydrogen-bonded acetate ligands, as evidenced by C NMR and IR spectroscopy.

Wastewater-based epidemiology to monitor 68 NPS/conventional drug use in Taipei metropolitan area in Taiwan during and after COVID-19 pandemic.

Amidst far-reaching COVID-19 effects and social constraints, this study leveraged wastewater-based epidemiology to track 38 conventional drugs and 30 new psychoactive substances (NPS) in northern Taiwan. Analyzing daily samples from four Taipei wastewater plants between September 2021 and January 2024-encompassing club reopenings, holidays, Lunar New Year, an outbreak, and regular periods-thirty-one drugs were detected, including 5 NPS. Tramadol, zolpidem tartrate, CMA, and MDPV were newly detected in Taiwanese sewage with frequency of 1.

Streamlining regular liquid chromatography with MALDI-TOF MS and NMR spectroscopy using automatic full-contact splitless spotting interface and flash-tap fractioning collection.

Background: High-resolution matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) and nuclear magnetic resonance (NMR) spectroscopy are powerful tools to identify unknown psychoactive substances. However, in complex matrices, trace levels of unknown substances usually require additional fractionation and concentration. Specialized liquid chromatography systems are necessary for both techniques.

Extended Magnetic Reconnection in Kinetic Plasma Turbulence.

Magnetic reconnection and plasma turbulence are ubiquitous processes important for laboratory, space, and astrophysical plasmas. Reconnection has been suggested to play an important role in the energetics and dynamics of turbulence by observations, simulations, and theory for two decades. The fundamental properties of reconnection at kinetic scales, essential to understanding the general problem of reconnection in magnetized turbulence, remain largely unknown at present.

Overexpression of OsHsp 18.0 in rice enhanced tolerance to heavy metal stress.

OsHsp18.0 plays a key role in cross-protection of rice seedlings from damages to photochemical systems and cellular membranes, caused by Cd and Cu stresses.

Rice OsHsp16.9A interacts with OsHsp101 to confer thermotolerance.

Class I small heat shock proteins (CI sHSPs), OsHsp16.9A and OsHsp18.0, share 74% identity in amino acid sequences and accumulate in response to heat shock treatments.

First-Principles Theory of the Relativistic Magnetic Reconnection Rate in Astrophysical Pair Plasmas.

We develop a first-principles model for the relativistic magnetic reconnection rate in strongly magnetized pair plasmas. By considering the energy budget and required current density near the x-line, we analytically show that in the magnetically dominated relativistic regime, the x-line thermal pressure is significantly lower than the upstream magnetic pressure due to the extreme energy needed to sustain the current density, consistent with kinetic simulations. This causes the upstream magnetic field lines to collapse in, producing the open outflow geometry which enables fast reconnection.

Separation of C1-C15 Alkanes with a Disk-Shaped Aluminum Column Employing Mesoporous AAO as the Stationary Phase.

A new type of gas chromatographic (GC) column employing a mesoporous anodic aluminum oxide (AAO) layer as the stationary phase was developed. The gas fluidic channels were fabricated on both sides of an aluminum disk via a mechanical stamping process. The tops of the gas fluidic channels were sealed with a thick aluminum foil and a thin glass liner.

Giant Zeeman Splitting for Monolayer Nanosheets at Room Temperature.

Giant Zeeman splitting and zero-field splitting (ZFS) are observed in 2D nanosheets that have monolayers of atomic thickness. In this study, single-crystalline CdSe(ethylenediamine) and Mn-doped nanosheets are synthesized via a solvothermal process. Tunable amounts of Mn(0.

Unique Growth Pathway in Solution-Solid-Solid Nanowires: Cubic to Hexagonal Phase Transformation.

Solution-solid-solid (SSS) nanowires can be catalyzed by superionic AgS ion diffusion. Here, we synthesize ZnS nanowires of the wurtzite crystal structure and heterostructures a low-temperature growth pathway. Single-crystalline ZnS nanowires were produced by varying reaction time and temperature (120-200 °C) thermal decomposition of a single-source precursor, Zn(DDTC).

Orientation and Stability of Asymmetric Magnetic Reconnection X Line.

The orientation and stability of the reconnection x line in asymmetric geometry is studied using three-dimensional (3-D) particle-in-cell simulations. We initiate reconnection at the center of a large simulation domain to minimize the boundary effect. The resulting x line has sufficient freedom to develop along an optimal orientation, and it remains laminar.

On the Collisionless Asymmetric Magnetic Reconnection Rate.

Unlabelled: A prediction of the steady state reconnection electric field in asymmetric reconnection is obtained by maximizing the reconnection rate as a function of the opening angle made by the upstream magnetic field on the weak magnetic field (magnetosheath) side. The prediction is within a factor of 2 of the widely examined asymmetric reconnection model (Cassak & Shay, 2007, https://doi.org/10.

Strongly localized magnetic reconnection by the super-Alfvénic shear flow.

We demonstrate that the dragging of the magnetic field by the super-Alfvénic shear flows out of the reconnection plane can strongly localize the reconnection x-line in collisionless pair plasmas, reversing the current direction at the x-line. Reconnection with this new morphology, which is impossible in resistive-magnetohydrodynamics, is enabled by the particle inertia. Surprisingly, the quasi-steady reconnection rate remains of order 0.

A Case Study of Connection Between Ground Magnetic Field Perturbations and Tail Current Sheet Bursty Flows at = -60 .

We report the first observations that connect a burst of fast flows and Pi2 fluctuations in the midtail current sheet at ~-60 with ground magnetic negative bays and Pi2 pulsations at high latitudes near 70°. Both the flow burst and negative bays occurred around midnight and were isolated and lasted for ~10 min. The flow burst had the characteristics of a low-density plasma bubble.

Why does Steady-State Magnetic Reconnection have a Maximum Local Rate of Order 0.1?

Simulations suggest collisionless steady-state magnetic reconnection of Harris-type current sheets proceeds with a rate of order 0.1, independent of dissipation mechanism. We argue this long-standing puzzle is a result of constraints at the magnetohydrodynamic (MHD) scale.

Cytotoxicity of Postmodified Zeolitic Imidazolate Framework-90 (ZIF-90) Nanocrystals: Correlation between Functionality and Toxicity.

Using a simple method, the aldehyde groups of zeolitic imidazolate framework-90 (ZIF-90) nanocrystals were converted into carboxyl, amino, and thiol groups, without affecting the integrity of the framework. Notably, for the first time, correlations between functionality and cytotoxicity are also demonstrated via in vitro cytotoxicity assays. The positive charged aminated-ZIF-90 presumably results in either perturbation of cell membrane, more efficient cell uptake, or both.

The Composition, Antioxidant and Antibacterial Activities of Cold-Pressed and Distilled Essential Oils of Citrus paradisi and Citrus grandis (L.) Osbeck.

The chemical composition and functional activities of cold-pressed and water distilled peel essential oils of Citrus paradisi (C. paradisi) and Citrus grandis (L.) Osbeck (C.

Formation of hollow silica nanospheres by reverse microemulsion.

Uniform hollow silica nanospheres (HSNs) synthesized with reverse microemulsion have great application potential as nanoreactors because enzymes or nanocatalysts can be easily encapsulated de novo in synthesis. Water-in-oil (w/o) reverse microemulsions comprising the polymeric surfactant polyoxyethylene (5) isooctylphenyl ether (Igepal CA-520), ammonia and water in a continuous oil phase (alkanes) coalesce into size-tunable silica nanoparticles via diffusion aggregation after the introduction of silica precursors. Here, we elucidate in detail the growth mechanism for silica nanoparticles via nucleation of ammonium-catalyzed silica oligomers from tetraethylorthosilicate (TEOS) and nanoporous aminopropyltrimethoxy silane (APTS) in the reverse microemulsion system.

Scaling of magnetic reconnection in relativistic collisionless pair plasmas.

Using fully kinetic simulations, we study the scaling of the inflow speed of collisionless magnetic reconnection in electron-positron plasmas from the nonrelativistic to ultrarelativistic limit. In the antiparallel configuration, the inflow speed increases with the upstream magnetization parameter σ and approaches the speed of light when σ>O(100), leading to an enhanced reconnection rate. In all regimes, the divergence of the pressure tensor is the dominant term responsible for breaking the frozen-in condition at the x line.

A general method for growing large area mesoporous silica thin films on flat substrates with perpendicular nanochannels.

Here we introduce a new synthetic approach to grow mesoporous silica thin films with vertical mesochannels on centimeter-sized substrates via an oil-induced co-assembly process. Adding an oil, i.e.

Two-dimensional semiconductor nanocrystals: properties, templated formation, and magic-size nanocluster intermediates.

CONSPECTUS: Semiconductor nanocrystals having an extended length dimension and capable of efficiently transporting energy and charge would have useful applications in solar-energy conversion and other emerging technologies. Pseudocylindrical semiconductor nanowires and quantum wires are available that could potentially serve in this role. Sadly, however, their defective surfaces contain significant populations of surface trap sites that preclude efficient transport.

Formation of hard power laws in the energetic particle spectra resulting from relativistic magnetic reconnection.

Using fully kinetic simulations, we demonstrate that magnetic reconnection in relativistic plasmas is highly efficient at accelerating particles through a first-order Fermi process resulting from the curvature drift of particles in the direction of the electric field induced by the relativistic flows. This mechanism gives rise to the formation of hard power-law spectra in parameter regimes where the energy density in the reconnecting field exceeds the rest mass energy density σ ≡ B(2)/(4πnm(e)c(2))>1 and when the system size is sufficiently large. In the limit σ ≫ 1, the spectral index approaches p = 1 and most of the available energy is converted into nonthermal particles.

Desolvation and dehydrogenation of solvated magnesium salts of dodecahydrododecaborate: relationship between structure and thermal decomposition.

Attempts to synthesize solvent-free MgB12H12 by heating various solvated forms (H2O, NH3, and CH3OH) of the salt failed because of the competition between desolvation and dehydrogenation. This competition has been studied by thermogravimetric analysis (TGA) and temperature-programmed desorption (TPD). Products were characterized by IR, solution- and solid-state NMR spectroscopy, elemental analysis, and single-crystal or powder X-ray diffraction analysis.