Development of a method using QuEChERS and LC-MS/MS for analysis of per- and polyfluoroalkyl substances in rice matrix.

Detection of per- and polyfluoroalkyl substances (PFAS) in food is crucial for ensuring food safety. Therefore, we combined a quick, easy, cheap, rugged, and safe (QuEChERS) extraction method with liquid chromatography-triple-quadrupole mass spectrometry (LC-MS/MS) to detect 35 PFAS in rice. The solvents (water and acetonitrile) were adjusted to pH 2.

Profile change of the volatile and non-volatile compounds in dried or baked laver by photooxidation.

Effects of light or dark storage condition on the profile changes of volatile and non-volatile compounds were evaluated in dried and baked laver for 60 days. Volatile and non-volatile compounds were analyzed using gas chromatography-mass selective detection and high-performance liquid chromatography-quadrupole-time of flight-mass spectrometry, respectively. Baked laver stored in light conditions for 60 days produced the most volatile compounds, whereas dried laver stored in the dark produced the least volatile compounds.

Changes in physicochemical properties and bacterial communities in aged Korean native cattle beef during cold storage.

During refrigerated storage, aged beef is liable to undergo alterations in its physicochemical properties. This study aimed to evaluate changes in the community of microorganisms, volatile compounds, and amino acids in aged beef under cold storage conditions. In addition, volatile basic nitrogen (VBN) values were measured to determine the putrefaction degree.

Evaluation of various clean-up sorbents in kale followed by LC-MS/MS analysis of pesticides.

Unlabelled: Chlorophyll-rich samples, such as kale, interfere with the analysis of residual pesticides and adversely affect the integrity of tandem mass spectrometers. Dispersed solid-phase (d-SPE) extraction using graphitized carbon black effectively removes pigments from kale extracts; however, it also reduces the recoveries of 30 pesticides. To overcome this, alternative sorbents, including ENVI-Carb, ChloroFiltr, and Z-Sep+, were evaluated in this study.

Toxin gene profiles, genetic diversity, antimicrobial resistance, and coagulase type of from cream-filled bakery products.

We determined the toxin gene profile, toxin production, antibiotic resistance coagulase serotype, and genetic diversity of 42 coagulase-positive (CPS) isolates collected from 1,464 cream-filled bakery products in Korea. Among the CPS isolates, 37 (88.1%) produced enterotoxin genes in combination with another toxin; 26 (61.

Solvent diffusion in polymer-embedded hollow nanoparticles studied by in situ small angle X-ray scattering.

In situ time-resolved small-angle X-ray scattering is introduced as a method to monitor the diffusion of a solvent in ceramic hollow nanoparticles (HNPs) supported by a polymer gel scaffold. Changes in the form factor were matched to discrete scattering models. A consecutive reaction kinetic model is used to analyze different stages of solvent diffusion.

Enhanced Electroresponsive Performance of Double-Shell SiO2/TiO2 Hollow Nanoparticles.

The double-shell SiO2/TiO2 hollow nanoparticles (DS HNPs) are successfully fabricated and adopted as dispersing materials for electrorheological (ER) fluids to investigate an influence of shell structure on ER properties. The DS HNPs-based ER fluid exhibits outstanding ER performance which is 4.1-fold higher compared to that of single shell SiO2/TiO2 hollow nanoparticles (SS HNPs)-based ER fluid.

Fabrication of Au@Ag core/shell nanoparticles decorated TiO2 hollow structure for efficient light-harvesting in dye-sensitized solar cells.

Improving the light-harvesting properties of photoanodes is promising way to enhance the power conversion efficiency (PCE) of dye-sensitized solar cells (DSSCs). We synthesized Au@Ag core/shell nanoparticles decorated TiO2 hollow nanoparticles (Au@Ag/TiO2 HNPs) via sol-gel reaction and chemical deposition. The Au@Ag/TiO2 HNPs exhibited multifunctions from Au@Ag core/shell NPs (Au@Ag CSNPs) and TiO2 hollow nanoparticles (TiO2 HNPs).

Dual-functional CeO2:Eu3+ nanocrystals for performance-enhanced dye-sensitized solar cells.

Single-crystalline, octahedral CeO2:Eu3+ nanocrystals, successfully prepared using a simple hydrothermal method, were investigated to determine their photovoltaic properties in an effort to enhance the light-harvesting efficiency of dye-sensitized solar cells (DSSCs). The size of the CeO2:Eu3+ nanocrystals (300-400 nm), as well as their mirrorlike facets, significantly improved the diffuse reflectance of visible light. Excitation of the CeO2:Eu3+ nanocrystal with 330 nm ultraviolet light was re-emitted via downconversion photoluminescence (PL) from 570 to 672 nm, corresponding to the 5D0→7FJ transition in the Eu3+ ions.

Fabrication of SiO2/TiO2 double-shelled hollow nanospheres with controllable size via sol-gel reaction and sonication-mediated etching.

Size-controllable double-shell SiO2/TiO2 hollow nanoparticles (DS HNPs) were fabricated using a simple sol-gel reaction and sonication-mediated etching. The size of the DS HNPs was controlled using SiO2 core templates of various sizes. Moreover, monodisperse DS HNPs were produced on a large scale (10 g per 1 batch) using the sol-gel method.

Multifunctional Ag-decorated porous TiO2 nanofibers in dye-sensitized solar cells: efficient light harvesting, light scattering, and electrolyte contact.

Designing the photoanode structure in dye-sensitized solar cells (DSSCs) is vital to realizing enhanced power conversion efficiency (PCE). Herein, novel multifunctional silver-decorated porous titanium dioxide nanofibers (Ag/pTiO2 NFs) made by simple electrospinning, etching, and chemical reduction processes are introduced. The Ag/pTiO2 NFs with a high surface area of 163 m(2)  g(-1) provided sufficient dye adsorption for light harvesting.

SiO(2) /TiO(2) hollow nanoparticles decorated with Ag nanoparticles: enhanced visible light absorption and improved light scattering in dye-sensitized solar cells.

Hollow SiO2 /TiO2 nanoparticles decorated with Ag nanoparticles (NPs) of controlled size (Ag@HNPs) were fabricated in order to enhance visible-light absorption and improve light scattering in dye-sensitized solar cells (DSSCs). They exhibited localized surface plasmon resonance (LSPR) and the LSPR effects were significantly influenced by the size of the Ag NPs. The absorption peak of the LSPR band dramatically increased with increasing Ag NP size.

Nanosilver-decorated TiO2 nanofibers coated with a SiO2 layer for enhanced light scattering and localized surface plasmons in dye-sensitized solar cells.

Enhanced harvesting of visible light is vital to the development of highly efficient dye-sensitized solar cells (DSSCs). Nanosilver-decorated TiO2 nanofibers (Ag@TiO2 NFs) were synthesized by depositing chemically reduced Ag ions onto the surface of electrospun TiO2 nanofibers (TiO2 NFs). The prepared Ag@TiO2 NFs were coated with SiO2 (SiO2@Ag@TiO2 NFs) by using PVP as coupling agent for protecting corrosion of Ag nanoparticle by I(-)/I3(-) solution.

Designed synthesis of SiO2/TiO2 core/shell structure as light scattering material for highly efficient dye-sensitized solar cells.

SiO2/TiO2 core/shell nanoparticles (STCS-NPs) with diameters of 110, 240, and 530 nm were fabricated to investigate the influence of the size and refractive index of light-scattering particles on light-scattering properties. The optical properties of STCS-NPs were evaluated and compared with SiO2-NPs and TiO2-NPs. The structure of STCS-NPs, consisting of a low refractive index core and high refractive index shell, provides efficient light scattering.

Characterizing size and porosity of hollow nanoparticles: SAXS, SANS, TEM, DLS, and adsorption isotherms compared.

A combination of experimental methods, including transmission and grazing incidence small-angle X-ray scattering (SAXS and GISAXS), small-angle neutron scattering (SANS), transmission electron microscopy (TEM), dynamic light scattering (DLS), and N(2) adsorption-desorption isotherms, was used to characterize SiO(2)/TiO(2) hollow nanoparticles (HNPs) of sizes between 25 and 100 nm. In the analysis of SAXS, SANS, and GISAXS data, the decoupling approximation and the Percus-Yevick structure factor approximation were used. Brunauer-Emmett-Teller, t-plot, and a spherical pore model based on Kelvin equation were applied in the treatment of N(2) isotherms.

Designed architecture of multiscale porous TiO2 nanofibers for dye-sensitized solar cells photoanode.

Multiscale porous (MSP) TiO(2) nanofibers (NFs) were fabricated using a simple electrospinning and etching process with TiO(2)/SiO(2) composite NFs for high-efficiency dye-sensitized solar cells (DSSCs). TiO(2) NFs with different pore sizes (small, large, and multiscale) were prepared using SiO(2) nanoparticles of various sizes. The surface area of the MSP TiO(2) NFs was nine times higher than that of pristine TiO(2) NFs, providing sufficient dye adsorption for light harvesting as well as efficient paths for electrolyte contact.

Aqueous synthesis of silver nanoparticle embedded cationic polymer nanofibers and their antibacterial activity.

This paper describes the one-pot, aqueous synthesis of cationic polymer nanofibers with embedded silver nanoparticles. Poly[2-(tert-butylaminoethyl) methacrylate] (PTBAM) was used as a cationic polymer substrate to reinforce the antimicrobial activity of the embedded silver nanoparticles. Electron microscope analyses revealed that the as-synthesized nanofibers had diameters of approximately 40 nm and lengths up to about 10 μm.

Electrospun ZnO/TiO2 composite nanofibers as a bactericidal agent.

Novel ZnO/TiO(2) composite nanofibers were fabricated by an electrospinning method and showed excellent antimicrobial activity against gram-negative Escherichia coli and gram-positive Staphylococcus aureus under UV irradiation and in the absence of light.