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Chromatic dispersion and thermal coefficients of 6 hygroscopic liquids: ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol (propane-1, 2-diol), and glycerol were measured in the range from 390 to 1070 nm for temperatures from 1 to 45 °C. A modified Abbe refractometer was utilised. Special care was taken to avoid contaminating the liquids under the test with water and solid particles. The measurement uncertainties were analysed. It was noticed that (in the given range and within the available measurement accuracy) the dependence of the refractive indices on the wavelength and temperature could be considered independently. Thus, thermal coefficients were found for each wavelength used, and their weak dependence on the wavelength was recognised. Then the Sellmeier equation was fitted to the experimental results for each temperature. [ABSTRACT FROM AUTHOR]

This document is a correction notice for an article titled "Chromatic dispersion and thermal coefficients of hygroscopic liquids: 5 glycols and glycerol" published in Scientific Data. The correction addresses errors in Figure 2 and Table 2 of the original article, which were inconsistent with other figures and had incorrect calculations. The corrected versions of Figure 2 and Table 2 have been updated in the PDF and HTML versions of the paper. The corrected values for the Sellmeier equation coefficients of the hygroscopic liquids are provided in the new Table 2. The authors of the article are Daniel Jakubczyk, Gennadiy Derkachov, Kwasi Nyandey, Sima Alikhanzadeh-Arani, and Anastasiya Derkachova. [Extracted from the article]

Three EM wave absorbing (FeNi, CoNi, and FeCo)/ZnS nanocomposites were synthesized by simple and successful process. By comparison, it was demonstrated that the maximum attenuation constant as well as magnetic loss parameter corresponds to the prepared FeNi/ZnS nanocomposite. It resulted in an optimum reflection loss of − 26.5 dB at about 12.2 GHz with a thickness of 5.9 mm. Based on the experimental results, the electromagnetic wave absorbing in this synthesized nanocomposite was attributed to the eddy current loss factor. [ABSTRACT FROM AUTHOR]

Nanomaterials are attracting increasing interest in many biomedical fields, including the fight against cancer. In this context, we successfully synthesized CoNi alloy nanoparticles (NPs) by a simple polyol process. The magnetic characteristics of the products were measured by vibration sample magnometry, which revealed that the samples have soft ferromagnetic behavior. The microstructure and morphology were inspected by X-ray diffraction and scanning electron microscopy, respectively. Human cancer cells derived from the breast (MCF7) and oral cavity (C152) and normal cells derived from human umbilical vein endothelial cells (HUVECs) were treated with increasing concentrations of CoNi NPs, and their cytotoxic effect was measured via MTT and lactate dehydrogenase (LDH) leakage assays. We found that treatments by using 12.5 to 400 µg/mL of Co0.5Ni0.5, Co0.6Ni0.4, and Co0.4Ni0.6 NPs were associated with significant concentration-dependent toxicity toward such cell lines and profoundly enhanced LDH leakage following 48 h of exposure (P < 0.05 compared with untreated cells). Besides, a NP dose of 6.25 µg/mL did not affect the survival of HUVECs while leading to marked cell death in MCF7 and C152 cells. In vivo experiments in rats were done to investigate the biochemical and histopathological changes over three weeks, following intraperitoneal administration of Co0.5Ni0.5, Co0.6Ni0.4, and Co0.4Ni0.6 NPs (100 mg/kg). As compared with the controls, the exposure to NPs caused significant elevations in aspartate aminotransferase, alanine aminotransferase, blood urea nitrogen, serum creatinine, serum catalase activity, serum superoxide dismutase, and liver malondialdehyde levels. Also, rats treated with Co0.6Ni0.4 NPs showed more severe histopathological changes of the liver and kidney. Our findings represent an essential step toward developing theranostic nanoplatforms for selective cancer treatment. [ABSTRACT FROM AUTHOR]

The polyol method has been used to synthesize CoNiFe and CoNiZn alloy nanoparticles (NPs). The magnetic characteristics of the products have been measured by vibration sample magnetometry (VSM) analysis. At the same time, the microstructure and morphology were inspected by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. Magnetic measurement of samples by the VSM indicated that samples have soft ferromagnetic behavior. Spherical-shaped grains for samples were confirmed by the SEM. MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and lactate dehydrogenase (LDH) assays were used to determine the cytotoxic effects of the synthesized NPs. Cytotoxic evaluations showed that treatment with 25 to 400 µg/mL of CoNiZn and CoNiFe NPs exerted a significant time- and concentration-dependent toxicity in MCF7 and HUVEC cells and markedly enhanced the LDH leakage after 48 h of exposure (p < 0.05 compared with untreated cells). Furthermore, NPs with concentrations higher than 12.5 µg/mL induced evident morphological changes in the studied cell lines. Treatment with 12.5 µg/mL of CoNiZn and CoNiFe NPs was safe and did not affect normal human cell survival. The results of in vitro cytotoxicity assessments show promise in supporting the suitability of the synthesized NPs to build high-performance theranostic nanoplatforms for simultaneous cancer imaging and therapy without affecting normal human cells. [ABSTRACT FROM AUTHOR]

One-pot polyol processing was successfully used for the preparation of FeNi nanoparticles. By increasing Ni concentration in FeNi alloy, the phase transition from bcc to fcc crystalline structure was clearly indicated by the XRD data as well as the measured hysteresis loops. FORC diagrams demonstrated that the prepared samples consist of single-domain magnetic particles with a uniform particle size. By changing the molar ratio of the precursors, different compositions of FeNi alloy were obtained. The influence of the temperature, solvent, surfactant, and amount of NaOH was also studied on the particle size, structure, and magnetic properties of the products. [ABSTRACT FROM AUTHOR]

Half-Heusler nanostructures of CoFeAl alloys, synthesized via coprecipitation route, were found to contain both hard- and soft-phases magnetic grains, mapped using first-order reversal curves (FORCs) diagrams. The obtained results confirmed that these powders are highly interacting as a single-domain magnetizing system. A significant dependence of the morphology and particle size on the annealing rate was represented by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and high-resolution TEM images. The presence of the strong magnetizing interaction between the nanoparticles led to the formation of chain-like structure stabilized by PVP polymer. By increasing the annealing rate from 278.15 K/min to 288.15 K/min (5 °C/min to 15 °C/min), the grain shape changed from long nanochain to nonuniform agglomerated grains. Additionally, the magnetic characteristics of the prepared alloys were found to be affected by tuning the annealing rate. [ABSTRACT FROM AUTHOR]

Magnetic hollow nanoparticles (HNPs) are of particular interest owing to their broad applications including targeted drug delivery and magnetic resonance imaging. Here, hollow Co2FeAl full-Heusler NPs were successfully synthesized using the polyethylene glycol polymer as a capping agent, followed by thermal annealing at 700 °C with heating rates ranging between 5 and 15 °C min−1. Increasing the heating rate up to 15 °C min−1 decreased the mean particle size, as characterized by scanning and transmission electron microscopy (TEM). High resolution TEM images revealed the highly crystalline nature of the HNPs with different grain size. A maximum saturation magnetization of 95 emu g−1 and coercivity of 730 Oe were obtained using heating rates of 5 and 10 °C min−1, respectively. Alternatively, first-order reversal curve (FORC) measurements at room temperature revealed the formation of a mixture of single-domain and superparamagnetic (SP) grains due to the presence of a wide range of particle sizes. With the increase in the heating rate, the SP contribution increased, which resulted in a decrease in the inter-particle magnetostatic interactions. Thereby, the average coercivity obtained from hysteresis curve was approached to FORC coercivity. [ABSTRACT FROM AUTHOR]

Nanoparticles of CoFeAl magnetic alloy was successfully fabricated in the presence of a well-known capping agent, polyvinyl alcohol, as a polymer template. The magnetic properties were studied using hysteresis curve and first-order reversal curve (FORC) measurements at room temperature. FORC diagrams demonstrated a wide distribution of the coercive field owing to the presence of different particle sizes in products. TEM image also showed that the synthesized samples are composed of some large clusters containing a few smaller particles. The maximum value of magnetization (~76 emu/g) and coercivity (573 Oe) were obtained in the annealed sample with 5 °C/min. A wider distribution of grain size with a smaller average of 20.5 nm as well as lower-degree of crystallinity was observed in the sample annealed with higher rate of 10 °C/min. [ABSTRACT FROM AUTHOR]

A systematic study of the size effect on the structural and magnetic properties of CoFeAl ternary alloys with different particle sizes has been performed in this work. The average particle size was controlled in a range from a few nanometers to micrometers by tuning the annealing rate. Upon annealing process at 700 °C in the presence of the surfactant matrix of CTAB, the B2-ordered structures with an average particle size of 35 nm were obtained under heating rate of 15 °C/min. Decreasing the reaction rate provided a well-arranged crystallization, leading to an enhanced saturation magnetization as well. For studying the effect of surfactant, samples were also synthesized in the absence of CTAB. A higher agglomeration is clearly observed in these samples compared to the previous ones, and the particle size was found to be significantly affected by the presence of surfactant, in spite of the magnetization. First-order reversal curve analysis revealed the presence of low- and high-coercive field particles in both samples, indicating that the products were composed of an assembly of particles with different sizes. By isolating the reversible and irreversible components of the magnetization, it was found that the behavior of the prepared samples is reversible (more than 59 %) as the percentage of the reversibility increased with decreasing the average particle size. [ABSTRACT FROM AUTHOR]

Superconducting nanoparticles, HoBaCuO, was successfully synthesized by protecting in a biopolymeric ethyl cellulose template. The embedded nanoparticles in the amorphous matrix of ethyl cellulose form the isolated site for outgrowth of Ho123 nanoparticles assemblies after breakdown of the polymer at temperatures above 500 C, according to Fourier transform infrared (FT-IR) spectra. Transmission electron microscope (TEM) and scanning electron microscopy (SEM) showed that the nanoparticles with uniform size less than 40 nm in the form of thin sheets with diameters in the range of 80 to 100 nm can be readily formed by controlling the concentration of the biopolymer. Structural analysis confirmed a pure and single phase of orthorhombic structure. By comparing to bulk materials, it was found that decreasing the particle size had no significant effect on the onset of superconductivity in the nanoparticles. [ABSTRACT FROM AUTHOR]

Clusters of DyBaCuO high T type II nanosuperconductor were prepared by sol-gel method in the presence of biopolymer chitosan. At the first step, the precursor and biopolymer were aggregated into amorphous matrix and then hydrogels were formed by thermogelling. Nucleation and growth of discrete nanoparticles is controlled by the biopolymer gel owing to retention of the fibrous nature of the chitosan at high temperatures up to 500 °C. After heating to 900 °C and complete decomposition of BaCO, nanoparticles of DyBaCuO superconductor with diameter of 10-20 nm in the form of nanoclusters are prepared. Critical temperature (T) of the nanoparticles was found to be above 83 K. Characterizations of specimens were performed using scanning electron microscopy and transmission electron microscopy, supported by other techniques including XRD diffraction, energy dispersive X-ray, FT-IR spectrum and magnetic susceptibility measurements. [ABSTRACT FROM AUTHOR]