Recent advancements in electrochemical sensors for the detection of vitamins, particularly vitamin D, have drawn a lot of attention due to their outstanding advantages of simplicity and high sensitivity. For the purpose of detecting vitamin D in this circumstance, recent research has focused on developing electrochemical sensors. Although there is always space for improvement, electrochemical sensors for vitamin D detection and its transformation into point‐of‐care devices have made great strides lately. For example, the development of innovative electrode materials that can increase sensitivity and selectivity continues to garner a lot of interest. New suggestions on adsorptive detections using vitamin D carriers like nanoclays or hydroxyapatite‐clay composites are being developed. These biosensors hold huge potential for the detection of cheap, disposable, and biodegradable solutions. Also, the biosensor could monitor the depletion of vitamin levels, providing a real‐time platform for the Internet of Medical Things, fifth‐generation wireless communications, and smartphone‐based electrochemical sensors. Currently, electrochemical sensors based on smartphones have been proposed to detect using various biomarkers for monitoring several changes in glucose, etc. We believe smartphone‐based electrochemical sensors and adsorptive sensing platforms provides a novel way toward point‐of‐care tests for identifying especially vitamin D deficiency and real‐time monitoring

In this study, solvent extraction is applied for extracting nickel from sulfate solutions containing iron and cobalt ions. This process can also be applied for the cleaning of waste solutions and for increasing solution concentrations after the leaching of low-grade nickel ores. Di-2-Ethylhexyl phosphoric acid (D2EHPA) was used as an extractant for this purpose. Effects of pH, aqueous/organic (A/O) phase ratio, iron, and cobalt ion contents of the solution on nickel extraction efficiency were investigated. The McCabe-Thiele diagrams for extraction and stripping steps were developed to determine the number of stages required. A total of two stages were required for 96.3% of Ni extraction and a total of two stages to strip nickel with 98% efficiency.

Interaction and adhesion forces between polymer and mineral fillers are key factors in controlling their affinity during the preparation of high-quality nanobiocomposites. In this work, the compatibility between polymer (alginate) and mineral filler (mica, borax or bentonite) surfaces was characterized by direct force measurements using atomic force microscopy (AFM). Direct force measurements, using a single spherical alginate particle prepared by the spinning disc atomization method and attached to a cantilever, have been employed to characterize adhesion forces between alginate and several mineral filler surfaces in air. The free energies of adhesion for alginate–mica, alginate–bentonite and alginate–borax systems were compared. The experimental adhesion forces for these systems were compared with those predicted using the Johnson– Kendall–Roberts (JKR) approximation and the Liftshitz–van der Waals and Lewis acid–base interaction theory. The discrepancies between the experimental values and theoretical predictions were discussed on the basis of the surface roughness effect on the measured adhesion forces.

The hydrometallurgical route of zinc hydroxide and synthesis of nanocrystalline ZnO is a particularly attractive method to recover oxidized lead and zinc from lead-zinc flotation tailings. In Turkey, lead-zinc complex/mixed ores along with high iron content are not suitable for conventional mineral processing methods and need hydrometallurgical treatments. Therefore, the control of iron during zinc processes is really important. In this study, hydrometallurgical process route for zinc recovery from Pb-Zn flotation tailings was investigated by considering the effects of H2SO4 concentration, leaching and roasting temperatures on the zinc dissolution considering the Eh-pH variations. The iron and zinc products were also individually examined by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) images in order to compare before and after leaching, precipitation and roasting steps. 83.1% Zn and 91.6% Cd leaching efficiencies were obtained from Pb-Zn flotation tailing particles with the size range of 50-110 nm from AFM image cross-sections, while lead and iron were not dissolved. Elemental sulfur started to form and produce a layer around the particles or a partially agglomerated particle in the size of 170 nm during the sulphuric acid leaching. However, majority of the particles was determined to be less than 20 microns, and AFM images showed that the size reduction between the leached and unleached particles was over 50%. Selective precipitations of iron and zinc in the form of hydroxide were performed in high recovery efficiencies of 90.1% and 99%, respectively. After the heat treatment, nanocrystalline zincite clusters of 96.6% purity were produced in the ZnO mineral form and nearly 13 nm in size. Zinc can be successfully recovered and a flotation tailings ore can be a good candidate for the production of high technology needs of nanocrystalline ZnO nanoparticles.