SnO2 microwires, nanowires and rice-shaped nanoparticles were synthesized by a thermal evaporation method. The diameters of microwire and nanowire were 2mand 50–100 nm, respectively, with approximately the same length (∼20m). The size of nanoparticles was about 100 nm. It was confirmed that the as-synthesized products have SnO2 crystalline rutile structure. The sensing ability of SnO2 particle and wire-like structure configured as gas sensors was measured. A comparison between the particle and wire-like structure sensors revealed that the latter have numerous advantages in terms of reliability and high sensitivity. Although its high surface-to-volume ratio, the nanoparticle sensor exhibited the lowest sensitivity. The high surface-to-volume ratio and low density of grain boundaries is the best way to improve the sensitivity of SnO2 gas sensors, as in case of nanowire sensor which exhibited a dramatic improvement in sensitivity to NO2 gas.

Different compositions of Bi5GexSe95
x (x ¼ 30, 35, 40 and 45 at %) thin films were deposited onto cleaned glass substrates by thermal evaporation method. The structural characterization revealed that, the as-prepared films of x ¼ 30, 35 and 40 at. % are in amorphous state but there are few tiny crystalline peaks of relatively low intensity for the film with x ¼ 45 at. %. The chemical composition of the asprepared Bi5GexSe65
x films has been checked using energy dispersive X-ray spectroscopy (EDX). The optical properties for the as-deposited Bi5GexSe65
x thin films have been studied. The additions of Ge content were found to affect the optical constants (refractive index, n and the extinction coefficient, k). Tauc’s relation for the allowed indirect transition is successfully describing the mechanism of the optical absorption. It was found that, the optical energy gap (Eg) decreases with the increase in Ge content. These obtained results were discussed in terms of the chemical bond approach proposed by Bicermo and Ovshinsky. The composition dependence of the refractive index was discussed in terms of the single oscillator model.

The effectofannealinginnitrogenatmosphereonstructuralandelectricalpropertiesofseleniumrich CdSe (SR-CdSe)thinfilmsdepositedbythermalevaporationontoglasssubstrateswerestudied.X-ray diffraction(XRD)patternsshowedthattheas-preparedfilmswereamorphous,whereastheannealed filmswerepolycrystalline.AnalyzingXRDpatternsrevealsthecoexistenceofbothSeandCdSe crystallinephaseswhichexhibitsahexagonalstructure.Themicrostructureparameters(crystallite size, microstrainanddislocationdensity)werecalculatedforannealedfilms. Temperaturedependence(300–500K)ofd.c.conductivitywasstudiedforas-preparedand annealedthinfilms.Theexperimentalresultsindicatethattheelectricalconductiontakingplace throughthermallyactivatedprocess.Athighertemperatures,electricalconductionforas-preparedfilm is takingplaceintheextendedstateswhilelocalizedstatesconductioninthebandtailsismostlikelyto take placeforannealedfilms.Regardingthelowertemperaturerange,conductionbyhoppinginthe localizedstatesneartheFermilevelisfoundtobedominant.Thus,conductivitydatainthisrangewas analyzedusingMott’svariablerangehoppingconduction,whereMott’sparameterswerecalculatedfor SR-CdSe thinfilms.

Structural and optical properties of selenium-rich CdSe (SR-CdSe) thin films prepared by thermal evaporation are studied as a function of annealing temperature. X-ray diffraction (XRD) patterns show that the as-prepared films were amorphous, whereas the annealed films are polycrystalline. Analyzing XRD patterns of the annealed films reveal the coexistence of both (hexagonal) Se and (hexagonal) CdSe crystalline phases. Surface roughness of SR-CdSe films is measured using atomic force microscope (AFM). Analyses of the absorption spectra in the wavelength range (200–2500 nm) of SR-CdSe thin films indicates the existence of direct and indirect optical transition mechanisms. The optical band gap (Eg) of as-prepared film is 1.92 and 2.14 eV for the indirect allowed and direct allowed transitions respectively. After annealing, the absorption coefficient and optical band gap were found to decrease, while the values of refractive index (n) and the extinction coefficient (kex) increase. The dispersion of the refractive index is described using the Wimple–Di Domenico (WDD) single oscillator model and the dispersion parameters are calculated as a function of annealing temperature. Besides, the high frequency dielectric constant (ε∞) and the ratios of the free carrier concentration to its effective mass (N/m*) are studied as a function of annealing temperature. The results are discussed and correlated in terms of amorphous-crystalline transformations.

Structural and optical properties of selenium-rich CdSe (SR-CdSe) thin films prepared by thermal evaporation are studied as a function of annealing temperature. X-ray diffraction (XRD) patterns show that the as-prepared films were amorphous, whereas the annealed films are polycrystalline. Analyzing XRD patterns of the annealed films reveal the coexistence of both (hexagonal) Se and (hexagonal) CdSe crystalline phases. Surface roughness of SR-CdSe films is measured using atomic force microscope (AFM). Analyses of the absorption spectra in the wavelength range (200–2500 nm) of SR-CdSe thin films indicates the existence of direct and indirect optical transition mechanisms. The optical band gap (Eg) of as-prepared film is 1.92 and 2.14 eV for the indirect allowed and direct allowed transitions respectively. After annealing, the absorption coefficient and optical band gap were found to decrease, while the values of refractive index (n) and the extinction coefficient (kex) increase. The dispersion of the refractive index is described using the Wimple–Di Domenico (WDD) single oscillator model and the dispersion parameters are calculated as a function of annealing temperature. Besides, the high frequency dielectric constant (ε∞) and the ratios of the free carrier concentration to its effective mass (N/m*) are studied as a function of annealing temperature. The results are discussed and correlated in terms of amorphous-crystalline transformations.

Structural and optical properties of selenium-rich CdSe (SR-CdSe) thin films prepared by thermal evaporation are studied as a function of annealing temperature. X-ray diffraction (XRD) patterns show that the as-prepared films were amorphous, whereas the annealed films are polycrystalline. Analyzing XRD patterns of the annealed films reveal the coexistence of both (hexagonal) Se and (hexagonal) CdSe crystalline phases. Surface roughness of SR-CdSe films is measured using atomic force microscope (AFM). Analyses of the absorption spectra in the wavelength range (200–2500 nm) of SR-CdSe thin films indicates the existence of direct and indirect optical transition mechanisms. The optical band gap (Eg) of as-prepared film is 1.92 and 2.14 eV for the indirect allowed and direct allowed transitions respectively. After annealing, the absorption coefficient and optical band gap were found to decrease, while the values of refractive index (n) and the extinction coefficient (kex) increase. The dispersion of the refractive index is described using the Wimple–Di Domenico (WDD) single oscillator model and the dispersion parameters are calculated as a function of annealing temperature. Besides, the high frequency dielectric constant (ε∞) and the ratios of the free carrier concentration to its effective mass (N/m*) are studied as a function of annealing temperature. The results are discussed and correlated in terms of amorphous-crystalline transformations.

Bi5GexSe95
x (30, 35, 40 and 45 at.%) thin films of thickness 200 nm were prepared on glass substrates by the thermal evaporation technique. The influence of composition and annealing temperature, on the structural and electrical properties of Bi5GexSe95
x films was investigated systematically using X-ray diffraction (XRD), energy dispersive X-ray analysis (EDX). The XRD patterns showed that the as-prepared films were amorphous in nature with few tiny crystalline peaks of relatively low intensity for 30 and 45 at.% and the Bi5Ge40Se55 annealed film was polycrystalline. The chemical composition of the Bi5Ge30Se65 film has been checked using energy dispersive X-ray spectroscopy (EDX). The electrical conductivity was measured in the temperature range 300e430 K for the studied compositions. The effect of composition on the activation energy (DE) and the density of localized states at the Fermi level N(EF) were studied, moreover the electrical conductivity was found to increase with increasing the annealing temperature and the activation energy was found to decrease with increasing the annealing temperature. The results were discussed on the basis of amorphous-crystalline transformations.

Theoretical calculations are described to investigate the behavior of solid explosive when heated by continuous and pulsed laser. A one-dimensional model is proposed and the numerical solutions have been obtained for the time-dependent nonlinear heat equation with the appropriate initial and boundary conditions. Relationships between various ignition parameters are analyzed and possible ignition mechanisms are discussed. Theoretical calculations are applied to the primary solid explosive b lead azide. It has been argued that the initiation of b lead azide with low energy laser is thermal in origin.

Theoretical calculations are described to investigate the behavior of solid explosive when heated by continuous and pulsed laser. A one-dimensional model is proposed and the numerical solutions have been obtained for the time-dependent nonlinear heat equation with the appropriate initial and boundary conditions. Relationships between various ignition parameters are analyzed and possible ignition mechanisms are discussed. Theoretical calculations are applied to the primary solid explosive b lead azide. It has been argued that the initiation of b lead azide with low energy laser is thermal in origin.

Oxidative stress is an imbalance between radical-generating and radicalscavenging activity, resulting in oxidation products and tissue damage. This study was aimed to evaluate the status of oxidative stress indices in blood of camels naturally infested with S. scabiei. Forty-seven male camels (Camelus dromedaries) were divided according to the extent of the infested area with Sarcoptes scabiei into four groups, mild (MID, n=12), moderate (MOD, n=10), severely infested (SEV, n=10) and healthy control group (n=15). Blood was used for determination of red cell count (RBC), hemoglobin (Hb), packed cell volume (PCV), serum nitric oxide (NO•, a free radical), ascorbate and albumin concentrations, and erythrocytic values of malondialdehyde (MDA, a marker of lipid peroxidation), protein carbonyls (PC, an indicator of protein oxidation), glutathione (GSH) superoxide dismutase (SOD) and catalase (CAT). Decreased levels (P0.05) of RBC, Hb, PCV, albumin and ascorbate were noticed in MOD and SEV compared to controls with the lowest values (P0.05) in SEV except for ascorbate, where MOD did not differ from SEV. Compared to controls, NO• gradually increased (P0.05) in MID followed by MOD and SEV, whereas MDA and PC were higher (P0.05) in MOD and SEV. PC was higher (P 0.05) in MOD than SEV. In addition, the antioxidants GSH, SOD and CAT were higher (P 0.05) in MID and lower (P0.05) in MOD and SEV compared to controls. GSH was lower (P0.05) in SEV compared to MOD. Besides, Hb was negatively correlated with NO• (r= −0.68, P0.001), MDA (r=−0.53, P0.001) and PC (r=−0.73, P0.001). In conclusion, dromedary sarcoptosis is accompanied by a state of oxidative stress process, which increased by increasing the area of infestation, and may contribute to the pathogenesis of the disease.