Gathering and sensing of nitrate ions in the environment due to the abundant use in industry and agriculture have become an important problem, which needs to be overcome. On the other hand, new materials such as carbon-based materials with unique properties have become an ideal choice in sensing technology. In this research, the high-density polyethylene (HDPE) polymer as a carbon source in the melted form was used and carbon nanoparticles in the form of a strand between two electrodes were analyzed. It was fabricated between copper electrodes by the pulsed arc discharge method. Subsequently, the constructed metal–nanoparticle–metal (MNM) contact was employed to recognize the nitrate ions. Therefore, NaNO3, Pb(NO3)2, Zn(NO3)2, and NH4NO3 samples as a usual pollutant of industrial and agricultural wastewater were examined. All nitrate compounds in ten different densities were tested and sensor I-V characteristic was investigated, which showed that all the aforesaid compounds were recognizable by the graphene nano-strand. Additionally, the proposed structure in the presence of ions was simulated and acceptable agreement between them was reported. Additionally, the proposed structure analytically was investigated, and a comparison study between the proposed model and measured results was carried out and realistic agreement reported.

Considering the importance of single-electron transistors (SETs), many studies have been done over the past decade to develop the use of SETs and improve their efficiency in both the experimental and theoretical fields. One of the most important challenges in SETs study is their optimization for use in humancompatible Nanobots for purposes such as drug delivery and destruction of cancer cells. Therefore, the use of human-compatible molecules as an island in these transistors is very significant. In this work, the density functional theory (DFT) & non-equilibrium Green's function (NEGF) methods have been used for SETs modeling study of the first principle computations in the coulomb barricade system of SETs based upon the metal-organic complex of ascorbic acid (vitamin C), thiamine (vitamin B1), riboflavin (vitamin B2), nicotinic acid (vitamin B3), pantothenic acid (vitamin B5), pyridoxine (vitamin B6), biotin (vitamin B7) and folic acid (vitamin B9). The isolated molecules and SET structures are analyzed based upon premises of overall energies, ionization energies, affection energies, addition energies, charging energies, gate coupling constant, density of states (DOS) plot, and charge stability diagrams (CSDs). It's established that riboflavin (vitamin B2) in the habitat of SET a decline in the additional energy and has the lowest addition energy and lowest charging energy at the neutral charge in the SET environment along with higher conductivity as evident from the CSD comparison has been revealed. Summing up the results and analyses indicate that a riboflavin molecule is a suitable option for SETs with a molecular island compatible with the human body.

The present study evaluates the contents in bioactive compounds, antioxidant activity, oil content and fatty acid composition of Capparis spinosa seeds. Samples were collected from 5 different habitats (AH: Ahar; KU: Kurdistan; U1, U2 and U3: Urmia) in Iran. The oil content in the seeds ranged from 16 to 27%. The predominant fatty acid was linoleic acid (45-50%) followed by oleic acid (30-39%), palmitic acid (2-8%) and stearic acid (2-3%). Total phenolic content (TPC) varied from 16.3 to 24.2 mg GAE/ g DW; total flavonoid content (TFC) ranged from 1.48 to 3.05 mg QE/g DW; and the antioxidant activity (DPPH assay) of the seeds was between 35 and 63%. The compounds obtained from different genotypes of C. spinosa seeds had different compositions, great antioxidant capacity and unsaturated fatty acids, and therefore could be a prospective source of natural bioactive molecules for the food and health industry.