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Cobalt ferrite is characterized by a partial inverse spinellic structure, which makes it a material with special magnetic properties that vary as a function of the cobalt concentration. The special magnetic properties represent one of the parameters due to which cobalt ferrite is of a great interest. In the present paper, we studied these properties from the perspective of the effect produced by the precursors of CoxFe3-xO4 nanomaterial synthesis on magnetic properties, shape, and morphology characteristics to these nanomaterials. Magnetic measurements were achieved with a SQUID magnetometer, while the structural and morphological characterization was achieved by X-ray diffraction (XRD), SEM- EDAX and AFM.

The aim of this paper was the syntheses and characterizations of functionalized zeolite materials with undoped and nitrogen-doped TiO2 nanocrystals. These materials were obtained by using alternative methods, namely sol-gel and hydrothermal, directly from precursors. The synthesis of TiO2 by sol-gel and hydrothermal methods was achieved in order to compare the crystalline structures and morphologies of TiO2 on the surface of the zeolite within the obtained hybrid materials. The obtained materials were characterized by X-ray diffraction (XRD), infrared spectroscopy (IR), and scanning electron microscopy (SEM) coupled with energy dispersive X-ray analysis (EDAX). The XRD results revealed that the natural zeolite used for the synthesis is mostly clinoptilolite and the anatase form of TiO2 for both applied methods. As it was desired, no the rutile phase of TiO2 was evidenced. The surface morphology observed by SEM analysis showed that TiO2 (spherical form) nanocrystals were attached on the zeolite surface. Therefore, the IR spectra confirmed the presence of TiO2 in to the zeolite lattice. The presence of the nitrogen ion in the materials obtained by both synthesis methods was also confirmed by EDAX spectra.

Zinc gallate (ZnGa2O4) is a normal spinel crystal structure (space group Fd3m). ZnGa2O4 has attracted much attention due its multitude of possible applications regarding field emission display, electroluminescent devices, and in the last decade mostly sensor domain. ZnGa2O4 nanoparticles were obtained by the hydrothermal method using Ga2O3 and Zn(NO3)2 x 6H2O precursors in basic medium using a Teflon-lined stainless steel autoclave tightly sealed. The synthesys was effectuated at 210°C for 4 h. The hydrothermal method is one of the most promising solution chemical methods. Thus, the size of particles and their distribution, phase homogeneity, and morphology could be well controlled. These powders were characterized by X-ray diffraction (XDR), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDAX), and atomic force microscopy (AFM). Photoluminescence (PL) measurements were obtained with a conventional lamp as an excitation source.

The document "Spectra Analysis and Plants Research 2.0" explores the significance of medicinal plants throughout history, their chemical compositions, and their applications in various industries. It highlights the importance of natural products in drug discovery and the use of advanced extraction and analytical techniques to study plant compounds. The research presented in the document covers a wide range of plant species and their metabolites, showcasing the potential of plants in pharmaceutical, nutraceutical, and cosmetic industries. The studies included in the document provide valuable insights into the therapeutic potential of plants and their bioactive components, emphasizing the importance of further research in this field. [Extracted from the article]

The development of cost-effective and high-performance technologies for wastewater treatment is essential for achieving a sustainable economy. Among the various methods available for water remediation, adsorption is widely recognized as an effective and straightforward approach for removing a range of pollutants. Gel materials, particularly hydrogels and aerogels, have attracted significant research interest due to their unique properties. Hydrogels, for instance, are noted for their ability to be regenerated and reused, ease of separation and handling, and suitability for large-scale applications. Additionally, their low cost, high water absorption capacity, and contribution to environmental protection are important advantages. Aerogels, on the other hand, are distinguished by their low thermal conductivity, transparency, flexibility, high porosity, mechanical strength, light weight, large surface area, and ultralow dielectric constant. This review provides a comprehensive analysis of the current literature, highlighting gaps in knowledge regarding the classification, preparation, characterization, and key properties of these materials. The potential application of hydrogels and aerogels in water remediation, particularly in removing contaminants such as dyes, heavy metals, and various organic and inorganic pollutants, is also discussed. [ABSTRACT FROM AUTHOR]

This paper presents results of the investigations regarding the obtaining and the characterization of the thermoelectric material Zn4Sb3 and (Zn1-xMx)4Sb3 where M = Ag and / or Sn. Obtaining of the materials was realized by melting high purity precursors into an oven where were kept isothermally for 12 hours at 1173 K. X-ray diffraction and scanning electron microscopy were used for structural and morphologic characterization. Optical band gap for each sample was determined from absorbance spectra recorded in the visible range 240-400 nm at room temperature. Electrical resistivity as function of temperature was measured and the electrical band gap was estimated for each of the obtained samples. The semiconducting behavior of the materials was reflected by these.

Globally, the human population steady increase, expansion of urban areas, excessive industrialization including in agriculture, caused not only decrease to depletion of non-renewable resources, a rapid deterioration of the environment with negative impact on water quality, soil productivity and of course quality of life in general. This paper aims to prepare size controlled nanoparticles of aluminum oxide using a simple synthesis method. The morphology and dimensions of nanomaterial was investigated using modern analytical techniques: SEM/EDAX and XRD spectroscopy. [ABSTRACT FROM AUTHOR]

The present paper is focused on studying the thermal behaviour of the Zn4Sb3 material. The thermal behavior of Zn4Sb3 was investigated using differential thermal analysis which was taken on the temperature range 300-1073K. The melting point and the solidification temperature of Zn4Sb3 were determined. Also, a characterization of the Zn4Sb3 material from an electrical point of view was done. It was shown the semiconducting behavior of the material as a function of temperature, and also as function of material electrical resistivity and electrical conductivity. Also, the optical and the electrical band gap were estimated. [ABSTRACT FROM AUTHOR]

Two samples of NaTaO3 perovskite materials were prepared by the standard hydrothermal method at the same reaction temperature (600 °C) but with different sintering times: 6 hours for sample S1 and 12 hours for sample S2. Using X-ray diffraction (XRD), it shows that samples S1 and S2 are mixtures of Na-Ta oxides (Ta2O5 and the prevailing phase NaTaO3). The scanning electron microscopy analysis (SEM), shows that the grains are connected each other in agglomerated clusters of size about few hundred nanometers. The frequency (f) dependencies of complex impedance, Z(f) = Z'(f) – i Z''(f) of the samples, over the frequency range 20 Hz – 2 MHz, at room temperature are presented. The real component Z' of the complex impedance decreases with increasing frequency and the imaginary component Z'' has two maximum corresponding to two relaxation processes. The results obtained from the complex impedance spectroscopy, Z''(Z') showed the appearance of two semicircles, corresponding to grain and grain boundary mechanism. Experimental results have been fitted with two parallel RC equivalent circuits connected in series and the parameters R and C have been evaluated. [ABSTRACT FROM AUTHOR]

Nanocrystalline powders of doped BiTe, with Ag (S1 sample), Sb (S2 sample), Sn (S3 sample) ions with different morphology and particle size 30-50 nm were prepared by a ultrasonically assisted hydrothermal method in alkaline aqueous solution with different concentration of NaBH as reducing agent at 200°C for 3 hours and 80% fill degree of autoclave. The influence of dopants and hydrothermal treatment conditions on the formation features, phase composition, particle size, morphology and properties of the products were investigated by X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, atomic force microscopy and electrical measurements. This paper reports a comparative study regarding the dopants influence to the shape and size of nano-structured thermoelectric materials. It was found that hydrothermal processing results in formation of low dimensional dispersion of doped BiTe nanostructures with desired shape and size and high degree of crystallinity with typical semiconductor behavior. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]