Various CVD-grown ZnO nanostructures for nanodevices and interdisciplinary applications.

This work presents a simple chemical vapour deposition (CVD) method to grow ZnO nanostructures. By annealing Zn powder under atmospheric pressure conditions, we collected nanocrystals with various morphologies, including rods, pencils, sheets, combs, tetrapods, and multilegs. Raman scattering study reveals that the samples are monophasic with a hexagonal structure, and fall into the 6 space group.

High Pressure-Driven Magnetic Disorder and Structural Transformation in Fe GeTe : Emergence of a Magnetic Quantum Critical Point.

Among the recently discovered 2D intrinsic van der Waals (vdW) magnets, Fe GeTe (FGT) has emerged as a strong candidate for spintronics applications, due to its high Curie temperature (130 - 220 K) and magnetic tunability in response to external stimuli (electrical field, light, strain). Theory predicts that the magnetism of FGT can be significantly modulated by an external strain. However, experimental evidence is needed to validate this prediction and understand the underlying mechanism of strain-mediated vdW magnetism in this system.

Correction: Structural, magnetic and hyperthermia properties and their correlation in cobalt-doped magnetite nanoparticles.

[This corrects the article DOI: 10.1039/D1RA07407E.].

Structural, magnetic and hyperthermia properties and their correlation in cobalt-doped magnetite nanoparticles.

Cobalt doped magnetite nanoparticles (Co Fe O NPs) are investigated extensively because of their potential hyperthermia application. However, the complex interrelation among chemical compositions and particle size means their correlation with the magnetic and heating properties is not trivial to predict. Here, we prepared Co Fe O NPs (0 ≤ ≤ 1) to investigate the effects of cobalt content and particle size on their magnetic and heating properties.

Minor hysteresis patterns with a rounded/sharpened reversing behavior in ferromagnetic multilayer.

Hysteresis of ferromagnetic system exhibits a fundamental stimulus-response behavior, thereby casting all the important macromagnetic system parameters such as coercivity, nucleation field, saturation magnetization, and hysteresis loss. Recently, increasing attention has been paid to exploration of relatively less understood minor loop behavior, since faster operation of magnetic devices is inevitably accompanied by minor hysteresis behavior from cycling among unsaturated ferromagnetic states. Here, we report our microscopic investigation of unusual minor hysteresis loop behavior, represented by rounded or sharpened response of minor hysteresis loop of (CoFeB/Pd) multilayer film.

One-step synthesis of NaLuGdF:Yb/Er(Tm) upconversion nanoparticles for in vitro cell imaging.

Upconversion nanoparticles (UCNPs) possess a unique type of photoluminescence (PL) in which lower-energy excitation is converted into higher-energy emission via multi-photon absorption processes. In this work, we have used a facile one-step hydrothermal method promoted water solubility to synthesis NaLuGdF:Yb/Er(Tm) UCNPs coated with malonic acid (MA). Scanning electron microscopy images and X-ray diffraction patterns reveal sphere-shaped UCNPs with an average size of ~80nm crystallized in the cubic NaLuF structure.

Au-Coated Honeycomb Structure as an Efficient TCO-Free Counter-Electrode for Quantum-Dot-Sensitized Solar Cells.

This study reports the fabrication of a Petri dish patterned with cylindrical micro-cavities that are produced using a one-step solvent-immersion phase-separation process. The developed 3D honeycomb Petri dish is coated with a Au film through a sputtering method to be an efficient Au-coated FTO-free electrode for quantum-dot-sensitized solar cells. Due to the high specific active surface area of the electrode with the Au-coated honeycomb structure, the energy conversion efficiency of devices that use this electrode is 5.

Tunable luminescent emission characterization of type-I and type-II systems in CdS-ZnSe core-shell nanoparticles: Raman and photoluminescence study.

We used wet chemical methods to synthesize core-shell nanocrystalline samples CdS(d)/ZnSe N , where d = 3-6 nm and N = 1-5 are the size of CdS cores and the number of monolayers grown on the cores, respectively. By annealing typical CdS(d)/ZnSe N samples (with d = 3 and 6 nm and N = 2) at 300 °C for various times t an = 10-600 min, we created an intermediate layer composed of Zn1-x Cd x Se and Cd1-x Zn x S alloys with various thicknesses. The formation of core-shell structures and intermediate layers was monitored by Raman scattering and UV-vis absorption spectrometers.

Defect-induced ferromagnetism of mechanical-milled BaTi0.98Mn0.02O3 nanoparticles.

Room-temperature ferromagnetism was found in BaTi0.98Mn0.02O3 nanoparticles fabricated by solid-state reaction and mechanical-ball milling.

Theoretical model for optical properties of porphyrin.

We propose a simple model to interpret the optical absorption spectra of porphyrin in different solvents. Our model successfully explains the decrease in the intensity of optical absorption at maxima of increased wavelengths. We also prove the dependence of the intensity and peak positions in the absorption spectra on the environment.

Electric potential profile of a spherical soft particle with a charged core.

The electrostatic potential profile of a spherical soft particle is derived by solving the Poisson-Boltzmann equations on a spherical system both numerically and analytically. The soft particle is assumed to consist of an ion-permeable charged outer layer and a non-permeable charged core with constant charged density. The contribution of the core to the potential profile is calculated for different charges and dielectric constants.

Repulsive interactions of a lipid membrane with graphene in composite materials.

The van der Waals interaction between a lipid membrane and a substrate covered by a graphene sheet is investigated using the Lifshitz theory. The reflection coefficients are obtained for a layered planar system submerged in water. The dielectric response properties of the involved materials are also specified and discussed.

The incidence and aetiology of hospitalised community-acquired pneumonia among Vietnamese adults: a prospective surveillance in Central Vietnam.

Background: Lower respiratory tract infection (LRTI) including Community-acquired pneumonia (CAP) is a common infectious disease that is associated with significant morbidity and mortality. The patterns of aetiological pathogens differ by region and country. Special attention must be paid to CAP in Southeast Asia (SEA), a region facing rapid demographic transition.

Raman scattering in Me-doped ZnO nanorods (Me = Mn, Co, Cu and Ni) prepared by thermal diffusion.

We have investigated normal and resonant Raman scattering in Me-doped ZnO nanorods (Me = Mn, Co, Cu and Ni) prepared by thermal diffusion. Experimental results show that the normal Raman spectra consist of the conventional modes associated with wurtzite ZnO and impurity-related additional modes. Under resonant conditions, only longitudinal optical (LO) phonon scattering and its overtones are observed.