Structural and dynamical properties of 13-atom Cu–Co mixed clusters

In this paper, the geometric structures and the melting-like processes of the 13-atom pure copper, pure cobalt cluster and their 13-atom mixed clusters are investigated and compared by the molecular dynamics method. The calculation shows that the pure copper and cobalt clusters have the standard icosahedral structures and the mixed clusters take on the deformed icosahedral structures. The quantitative analysis shows that the deformations are slight. Moreover, an element similarity function is introduced by which the contribution of the compositions of the clusters to the deformation of the mixed clusters is analyzed and discussed. With the increase of the temperature, the migrating and recombination of the atoms on the surface of the clusters are observed, indicating the starting of the transition from solid-like to liquid-like state for the clusters. Through the calculating of the relative root-mean-squared pair separation fluctuation and monitoring the dynamical structures of the clusters, it is found that the mixed clusters experience a multi-step process in the transition.

Development of Graphene Based Cobalt-Ferrites Nanocomposites for Microwave Shielding

The study is related to cobalt ferrites nanocomposites embedded with graphene nanosheets, prepared by co-precipitation method. Various doping of graphene from 0.1% up to 1% were applied within the cobalt ferrite structure to study its microwave and mechanical effects on the nanocomposites. Microstructural analysis confirms the homogeneous dispersion and successful adhesion of graphene nanosheets within the cobalt ferrite matrix. Microwave absorbing capacity of these samples was studied by Agilent network analyzer in low frequency band of microwave (1MHz to 2 GHz), Results reveals that graphene incorporation not only improved the absorption capacity of cobalt ferrites (13dB-17d), but also widened its maximum absorption peak. This change was supposed to be due to inhomogeneity and combine effects of electric (graphene), and magnetic dielectric nature (cobalt ferrites). Further mechanical characterizations reveal that our composites samples have higher flexural strength (19.92 MPa for 1% loading) and improved toughness (>6000 J/mm2) compare to pure cobalt ferrites (10.28 MPa, 1000 J/mm2).

Production, Purification, and Applications of a Potential Theranostic Pair: Cobalt-55 and Cobalt-58m

The emerging success of [68Ga/177Lu]Ga/Lu-DOTATATE as a theranostic pair has spurred interest in other isotopes as potential theranostic combinations. Here, we review cobalt-55 and cobalt-58m as a potential theranostic pair. Radionuclidically pure cobalt-55 and cobalt-58m have been produced on small cyclotrons with high molar activity. In vitro, DOTATOC labeled with cobalt has shown greater affinity for SSTR2 than DOTATOC labeled with gallium and yttrium. Similarly, [58mCo]Co-DOTATATE has shown improved cell-killing capabilities as compared to DOTATATE labeled with either indium-111 or lutetium-177. Finally, PET imaging with an isotope such as cobalt-55 allows for image acquisition at much later timepoints than gallium, allowing for an increased degree of biological clearance of non-bound radiotracer. We discuss the accelerator targetry and radiochemistry used to produce cobalt-55,58m, emphasizing the implications of these techniques to downstream radiotracers being developed for imaging and therapy.

Preparation of Nano Ink Using Cobalt Ferrite and Barium Titanate for Printed Electronic Devices

Lead in our body is toxic and hazardous. Here leadfree Cobalt ferrite and Barium Titanate inks have been prepared and fabricated. The prepared inks remained stable without agglomeration or condensation during preservation. Cobalt Ferrite and Barium Titanate Nano inks have been characterized using X-ray diffraction method and UV Visible Spectroscopy. By the analysis of X-ray diffraction (XRD), the resultant inks were confirmed to be of pure Cobalt Ferrite and Barium Titanate powders with cubic structure and tetragonal structure respectively. Lattice parameters and grain size have been determined by X-ray diffraction method. UV Visible Spectroscopy analysis has been done to obtain the band gap energy of the prepared inks. The preparation and characterization of Cobalt Ferrite and Barium Titanate Nano inks are comprehensively demonstrated in this paper.

Role of edta capped cobalt oxide nanomaterial in photocatalytic degradation of dyes

Dyes released from textile, paint, and various other industries in wastewater have posed long term environmental damage. Functional nano-materials provide a hope and opportunities to treat these effluent wastes in a rapid and efficient way due to their large surface area to volume ratios. Synthesis of 2,2',2'',2'''-(Ethane-1,2-diyldinitrilo)tetraacetic acid (EDTA) cap-ped cobalt oxide nanomaterial as a photocatalyst has been investigated and utilized for the rapid and efficient removal of malachite green (MG) and crystal violet (CV) dyes. The morphological, structural, optical, chemical and thermal properties of the synthesized nanomaterial were investigated using different characterization tools such as Scanning electron microscopy(SEM), Transmis-sion electron microscopy (TEM), X-ray diffraction (XRD), Ultra violet visible (UV-Vis), Fourier transform infrared (FT-IR) spectroscopy and Thermogra-vimetric analysis (TGA) etc. The prepared EDTA capped Cobalt oxide nanomaterials display better photocatalytic degradation, 56.3 % for MG and 37.9 % for CV in comparison to the pure Cobalt oxide, 47.7 and 27.6 %, respectively under visible light illumination. The kinetics study followed the pseudo-first order kinetic model and Freundlich adsorption isotherm model. The incremental photodegradation of these two dyes was attributed by mor-phology of the nanomaterial which favour effective electron/hole separation.

Synthesis and Characterization of Pure Cobalt Ferrite for DC Electrical

Ferrite Cobalt (CoFe2O4) is a distinguished magnetic material with average enforcement and average magnitude of magnetization. It has a distinct chemical stability and mechanized hardness. It is an expectant advocate for the procedure of sensory devices and actuators, as a definitive sealing, magnetic drug target, and electrical devices and has an extensive range of research in material technology/science for technological uses/applications. The naoparticles of cobalt ferrite on an entangled effectively processed at ambient temperature through a simple co-precipitation process. The crystal structure & morphology of symbol was determined by XRD and SEM. The XRD spectrum confirms that the composite nanoparticles are formed by the perfect spinel structure. The average rate of crystals was determined by means of Modified Scherer (54nm) and Williamson-Hall (49nm) methods. A SEM view showed the nanoparticles CoFe2O4 being grouped in nearby structures. The bond and visual features were described by FTIR and UV-Vis Spectrum. Compared with other absorbing bands informed in literature, this material shows a very large intake band between 350 and 600 cm-1 in the FTIR test. More than one pitch in UVVis spectrum is seen with a direct straight band gap identified of 4.1 eV and 4.9 eV. This is again in contrast to other reports in literature. These irregular outcomes express that although a very good spinel structure is in place, coordination of the symbols in the cells of the unit is different here. An electronic DC training for the temperatures cobalt ferrite was tested for temperature, which again showed some interesting results from those reported in literature. This combination of irregular buildings in considerable degree of the ferrite needs to demonstrate a deeper analysis of the overall structure and characteristics of cobalt ferrite in comparison to these methods.

Study of Heating and Cooling Rate of Cobalt Oxide-Based TCES System Using Experimental Redox Kinetics Analysis

Cost-effective solar power generation in CSP plants requires the challenging integration of high energy density and high-temperature thermal energy storage with the solar collection equipment and the power plant. Thermochemical energy storage (TCES) is currently a very good option for thermal energy storage, which can meet the industry requirement of large energy density and high storage temperature. TCES specifically exploits reversible chemical reactions wherein heat is absorbed during the forward endothermic reaction and released during the reverse exothermic reaction. The associated enthalpic storage of energy (i.e., the heat of reaction) offers higher density and enhanced stability compared to sensible and latent heat storage. Metal oxide redox reactions are particularly well-suited for TCES given their characteristically high enthalpy of reaction and high reaction temperature. In addition, the air is suitable as both a heat transfer fluid (HTF) and reactant; thus, simplifying process design and eliminating the need for indirect HTF storage and any intermediate heat exchanger. Among the palette of available metal oxides, cobalt oxide is one of the most promising candidates for TCES given its high enthalpy of reaction with high reaction temperature. One of the critical design parameters for TCES reactors is the optimal heating and cooling rates during respective charging and discharging modes of operation. In order to study the effect of heating/cooling rate on cobalt oxide TCES performance, a constant 10°C/min rate was selected for both storage cycle heating and cooling. Considering the intrinsic redox kinetics of cobalt oxide at considered constant heating/cooling rate, we studied milligram scale quantities of cobalt oxide (99.9% purity, 40 μm average particle size) using a dual-mode thermogravimetric (TGA)/differential scanning calorimetry (DSC) system, which simultaneously measures weight change (TGA) and differential heat flow (DSC) as a function of TCES cycling under continuous air purge. In addition, we investigated the cyclic stability of cobalt oxide in the context of the redox kinetics and particle coarsening behavior, employing scanning electron microscopy (SEM). TGA/DSC tests were conducted for 30 successive cycles using pure cobalt oxide. It was shown that pure cobalt oxide in powder form (38μ particle size) could complete both forward and reverse reaction at the selected heating rate with little degradation between cycles. In parallel, SEM was used to examine morphology and particle size changes before and after heating cycles. SEM results proved grain growth occurs even after only five initial cycles.