TiN films were prepared by the Cathodic arc evaporation deposition method under different negative substrate bias. AFM image analyses show that the growth mode of biased coatings changes from 3D island to lateral when the negative bias potential is increased. Nanohardness of the thin films was measured by nanoindentation, and residual stress was determined using Grazing incidence X ray diffraction. The maximum value of residual stress is reached at −100 V substrate bias coinciding with the biggest values of adhesion and nanohardness. Nanoindentation measurement proves that the force-depth curve shifts due to residual stress. The experimental results demonstrate that nanohardness is seriously affected by the residual stress.

Huanglongbing (HLB) is the most destructive disease of citrus worldwide. The disease is caused by the proto-bacteria Candidatus Liberibacter asiaticus and transmitted by the Asian citrus psyllid Diaphorina citri. HLB symptoms are slow to appear while the tree continues to be a source of inoculum. Monitoring tree health and rapid detection of HLB is critical for sustainable citrus production. Currently, scientists are working on developing new techniques for pre-symptomatic detection of HLB, as there is no available method for real-time assessment of tree health. In this study, we demonstrate the rapid and efficient discrimination between healthy and HLB-affected citrus by laser-induced breakdown spectroscopy combined with chemometric analysis. Healthy and HLB-affected trees were differentiated with a high degree of precision. The novelty of this method lies in the fingerprinting of healthy and diseased plants based on their organic and inorganic constituents, and the use of a multi-pulse laser coupled with a microscope to take spectra of the plant phloem.

Size-selected TiN nanoclusters in the range of 4 to 20 nm have been produced by an ionized cluster beam, which combines a glow-discharge sputtering with an inert gas condensation technique. With this method, by controlling the experimental conditions, it was possible to produce nanoparticles with a high control in size. The size distribution of TiN nanoparticles was determined before deposition by mass spectroscopy and confirmed by atomic force microscopy. The size distribution was also analyzed using a high-resolution transmission electron micrograph. The photoluminescence [PL] spectra of TiN nanoparticles at different sizes were also experimentally investigated. We reported, for the first time, the strong visible luminescence of TiN nanoparticles on Si (111) wafer due to the reduced size. We also discussed the PL intensity as a function of the nanoparticle size distribution.

Tobacco is an agricultural product originating in America that is obtained by processing the leaves of various plants of the genus Nicotiana tabacum. It is the inedible product occupying the most plantings in the world, according to a recent report from the United Nations Food and Agriculture Organization. It is consumed in various ways, but the most popular form of consumption is, undoubtedly, by smoking cigarettes. A particular segment of the tobacco industry is the manufacturing of handmade cigars, which for some third-world countries is an important source of income. There are different qualities of cigars, and a major problem is the adulteration that occurs, for example, when authentic high-quality leaves are replaced by lower quality leaves. A factor that influences the quality of the cigars is the smoke combustion process, which depends on several factors, particularly the composition of the leaves. We present a simple and quick technique for the quality control and origin identification of handmade cigars that measures the Mg/Ca ratios in the tobacco leaves and wrappers of the cigars using laser-induced breakdown spectroscopy.

We show a new laser-induced breakdown spectroscopy (LIBS) setup based on a small, ultracompact, and low-cost excitation source developed by the authors. The laser is a compact Nd:YAG laser emitting in the multipulse $Q$-switch regime and is capable of delivering a bunch of pulses with a total energy up to 300 mJ. The developed system is applied to the analysis of Pb and Cu contaminants on fish. LIBS spectra were obtained from scales, muscle, and skin of fresh and frozen samples. The developed excitation source is able to detect 0.25 mg/Kg and 0.20 mg/Kg of Pb and Cu, respectively. In this way, the equipment seems to be adequate to achieve a screening analysis of those contaminants.