This study investigated the mechanical characteristics of components produced from composite Polylactic Acid reinforced with Carbon Fibers (PLA-CF). PLA and PLA-CF were produced with strict rules regarding layer thickness, nozzle diameter, printing speed, and orientation. PLA-CF exhibited superior tensile characteristics, Izod impact test values, and higher crystalline degree than PLA. Samples with density values of 20%, 40%, 60%, 80%, and 100% were tested for ultimate tensile strength. It was shown that the PLA-CF UTS samples at 100% infill density (45.292 MPa) surpassed the PLA samples (42.235 MPa). As the strength values increased, the Izod impact strength followed the same pattern with infill density. The Grey Relational Analysis (GRA) approach was employed to optimize the infill density in order to enhance the dimensional accuracy. The aforementioned parameter was found to have a more significant influence on product quality and time reduction in the Fused Filament Fabrication (FFF) process.

Electronic sensors for volatile organic compounds have been prepared by drop-casting dispersions of multi-wall carbon nanotubes (MWCNTs) in aqueous solutions of λ-DNA onto Pt microband electrodes. The MWCNTs themselves show a metal-like temperature dependence of the conductance, but the conductance of DNA/MWCNT composites has an activated component that corresponds to inter-tube tunneling. The resistance of the composite was modelled by a series combination of a term linear in temperature for the nanotubes and a stretched exponential form for the inter-tube junctions. The resistance may increase or decrease with temperature according to the composition and may be tuned to be almost temperature-independent at 67% by mass of DNA. Upon exposure to organic vapours, the resistance of the composites increases and the time-dependence of this signal is consistent with diffusion of the vapour into the composite. The fractional change in resistance at steady-state provides an analytical signal with a linear calibration and the presence of DNA enhances the signal and adjusts the selectivity in favour of polar analytes. The temperature dependence of the signal is determined by the enthalpy of adsorption of the analyte in the inter-tube junctions and may be satisfactorily modelled using the Langmuir isotherm. Temperature and pressure-dependent studies indicate that neither charge injection by oxidation/reduction of the analyte nor condensation of analyte on the device is responsible for the signal. We suggest that the origin of the sensing response is an adsorption of the analyte in the inter-tube regions that modulates the tunneling barriers. This suggests a general route to tuning the selectivity of MWCNT gas sensors using non-conductive polymers of varying chemical functionality.

A novel screen-printed electrode (SPE) modified by CoMoO4 nanosheets (CoMoO4 NSs) was designed to analyse hydrochlorothiazide. Cyclic voltammetry, chronoamprometry and differential pulse voltammetry using the developed electrode were performed to evaluate its electrochemical behaviour. Further, the anodic peak currents for hydrochlorothiazide at CoMoO4 NSs modified SPE were almost 4 times higher than for the untreated SPE. Between the concentration range of 0.1 to 400.0 μM, the modified electrode's response was directly proportional to the concentration, and it could detect hydrochlorothiazide at a very low level of 0.05 μM (S/N = 3). Hydrochlorothiazide was also measured using the modified electrode when methyldopa was present. The sensor offers various advantages for the analysis of hydrochlorothiazide detection, including moderate cost, ease of preparation and consi­derable sensitivity.

Nano-crystalline CdTe films were coated on glass and silicon substrates using the vacuum evaporation (PVD) technique, with annealing temperatures of 25, 100, 150, and 200 °C. This study aims to create a simple photoelectric cell using the effective light-absorbing layer CdTe as a thin film and Si as an n-type semiconductor. Additionally, it investigates the properties of CdTe thin films annealed at various temperatures. The following equipment was used: XRD, UV-visible spectrophotometer, SEM, and AFM. Moreover, the electrical characteristics of the fully designed devices were tested using I-V measurements and the Hall effect. Thin-film photovoltaics could become the primary source of global electricity. The CdTe thin films were coated using thermal evaporation. The best efficiency was 0.99% for the CdTe/Si structure with Voc = 5.0 x 10-1 V, Jsc = 51.0 x 10-2 mA/cm2, FF = 0.39, at 25 °C, and the efficiency decreased with increasing temperature. It has been found that annealing temperatures have an impact on the size of crystallites, the values of energy gaps, and the electrical properties of CdTe thin films.

This work fabricated a NO2 gas sensor by depositing Fe3O4 on a quartz substrate using a pulsed laser deposition method with energies of (700 and 900) mJ. The XR