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ABSTRACTThe Nickel ferrite (NiFe2O4) nanoparticle size was successfully prepared using the sol-gel method, while, the conducting polymer (PANI-PTSA) the chemical oxidative method was used. The nanocomposite {NiFe2O4/PANI-PTSA} is an excellent shielding material that reduces the cross-sectional area by absorbing radar waves at X-band, then offers protection from risky microwave radiation. The specimens NF, PNF1, PNF2 and PNF3 were characterised using some techniques, for instance, X-ray diffraction (XRD), Fourier transforms infrared (FTIR) and vector network analyser (VNA). Results showedthat the specimen PNF3, which mixed by ratio (3:1) and 2.1 mm thickness, got better reflection loss (R.L); { – 19.5, – 25.19, – 59.08} dB, at frequency band {8.3, 9.5, 10.7} GHz, respectively, while the power absorption was (99 %), (>99.68%), (99.99 %) in that order. Here the nanocomposite {NiFe2O4/PANI-PTSA} adds new outcomes to the electromagnetic interference (EMI) for shielding and microwave absorption in various advanced military applications at frequency band (8–12 GHz).

AbstractA solvent free in situmicrowave hydro-distillation method for extraction of essential oil from fresh ginger root it presented. Extraction was conducted in a TE10nsingle-mode microwave cavity and variable power 2 kW generator operating at 2.45GHz. The main extracted components identified by gas chromatography (GC) were Zingiberene, α-Curcumene, β-Sesquiphellandrene and α-Selinene. At energy inputs of 0.40 kWh/kg higher powers and shorter exposure times, crucially did not degrade the highly volatile components (α-Pinene and Camphene) despite providing the highest essential oil yields. Optimum processing conditions were found to be 1000W (0.40kWh/kg) for 5 min, for whole ginger root, where 0.35g oil/100g plant was obtained. This was compared to a yield of 0.2g/100g plant in 150 in using conventional hydro-distillation and 0.3g/100g plant in 90 min using a multi-mode microwave cavity-based hydro-distillation.

In this study, twenty-four amperometric dot microsensors based on carbon materials, (e.g., graphite (G) and graphene (GR) and carbon nanopowder (CN)), unmodified and modified with TiO2, and phthalocyanines: basic phtalocyanine (Pc), FeIIIphthalocyanine (FeIIIPc) and FeIIphthalocyanine (FeIIPc) are evaluated and tested for their ability for the analysis of serotonin (5-HT) in biological fluids (e.g. urine samples), using differential pulse voltammetry (DPV). Cyclic voltammetry (CV) was used to optimize the working conditions, e.g., pH, and electrolyte for the amperometric dot microsensors revealing (0.1 mol L[?]1) KCl and pH = 3.0 phosphate buffer as the optimum electrolyte and pH conditions for the assay of serotonin. The selected amperometric dot microsensors with preference to the G-FeIIIPc followed by the GR-FeIIIPc modified microsensors were used for the reliable analysis of serotonin in urine samples, with recoveries higher than 94.00%.

In this study, new amperometric dot microsensors based on graphene and phthalocyanines: basic phtalocyanine, FeIIIphthalocyanine and CoIIphthalocyanine are proposed for the assay of adenine, guanine and epinephrine in real biological fluids (e.g. urine samples), using differential pulse voltammetry (DPV). Cyclic voltammetry (CV) was used to optimize the working conditions, e.g., pH, and electrolyte for the proposed dot microsensors obtaining an optimum of 0.1 mol L[?]1 KCl or 0.1 mol L[?]1 KNO3 in a phosphate buffer solution at a pH = 4.0. The lowest limits of detection obtained for adenine (2.5 x 10[?]6 mol L[?]1), guanine (1.4 x 10[?]5 mol L[?]1), and epinephrine (1 x 10[?]6 mol L[?]1), as well as the selectivity coefficients made possible their assay in urine samples with high reliability (RSD < 1.0%). Adenine, guanine and epinephrine were recovered reliably from urine samples in percentages higher than 90.00%.

This work presents a hybrid technology and two hybrid installations (HI-1 and HI-2) for volatile organic compounds (VOCs) removal using successive or simultaneous microwave (MW) irradiation, electron beam (EB) irradiation, and catalytic oxidation. HI-1 is designed for successive EB and MW irradiation with two distinct reactors, both containing a catalyst inside. HI-2 is designed for simultaneous EB and MW irradiation in the same reactor containing a catalyst. Real synergistic effects between non-thermal plasma (NTP) and catalysis were obtained by introducing the catalyst into the irradiation zone, i.e. into the MW reactor, EB reactor or into a reactor in which both EB and MW are injected.

In this study, twenty-four amperometric dot microsensors based on carbon materials, (e.g., graphite (G) and graphene (GR) and carbon nanopowder (CN)), unmodified and modified with TiO2, and phthalocyanines: basic phtalocyanine (Pc), FeIIIphthalocyanine (FeIIIPc) and FeIIphthalocyanine (FeIIPc) are evaluated and tested for their ability for the analysis of serotonin (5-HT) in biological fluids (e.g. urine samples), using differential pulse voltammetry (DPV). Cyclic voltammetry (CV) was used to optimize the working conditions, e.g., pH, and electrolyte for the amperometric dot microsensors revealing (0.1 mol L−1) KCl and pH = 3.0 phosphate buffer as the optimum electrolyte and pH conditions for the assay of serotonin. The selected amperometric dot microsensors with preference to the G-FeIIIPc followed by the GR-FeIIIPc modified microsensors were used for the reliable analysis of serotonin in urine samples, with recoveries higher than 94.00%.

In this study, new amperometric dot microsensors based on graphene and phthalocyanines: basic phtalocyanine, FeIIIphthalocyanine and CoIIphthalocyanine are proposed for the assay of adenine, guanine and epinephrine in real biological fluids (e.g. urine samples), using differential pulse voltammetry (DPV). Cyclic voltammetry (CV) was used to optimize the working conditions, e.g., pH, and electrolyte for the proposed dot microsensors obtaining an optimum of 0.1 mol L−1KCl or 0.1 mol L−1KNO3in a phosphate buffer solution at a pH = 4.0. The lowest limits of detection obtained for adenine (2.5 × 10−6mol L−1), guanine (1.4 × 10−5mol L−1), and epinephrine (1 × 10−6mol L−1), as well as the selectivity coefficients made possible their assay in urine samples with high reliability (RSD < 1.0%). Adenine, guanine and epinephrine were recovered reliably from urine samples in percentages higher than 90.00%.