Deep investigations were performed for further understanding of the nanostructure of sputtered WO3 ˆlms. The as-deposited ˆlms consisted of ˆne crystallites of several nm. As the pressure increased, the ˆlm density decreased and the surface area increased owing to open pores between grains. When ˆlms were annealed at 400°C or above, they were well crystallized to form monoclinic and randomly-shaped grains. Upon this crystallization, the ˆlm shrank and its density increased slightly, while the relative surface area substantially decreased.

Tungsten oxide nanowires were prepared by a vapor transport method using WO3 powder as a raw material. The crystal structure and morphology of WO3 nanowires were investigated by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The obtained nanowires were hexagonal WO3. The major factors that influenced the morphology were the furnace temperature and the substrate position. The diameter of the nanowires decreased as the distance of the substrate from the raw material increased. Sensors were fabricated by pouring a few drops of nanowire-suspended ethanol onto oxidized Silicon substrates equipped with a pair of interdigitated Pt electrodes. The sensor made of the nanowires as thin as 50 nm showed the highest response to NO2 at a low operating temperature of 100 ◦C. The temperature dependence of the response was discussed in relation to the formation of NO2 − and NO3 − ions on the surface of WO3. The response slightly increased with decreasing diameter if the nanowires are regional depleted in NO2, while it largely increased if the nanowires are in volume depletion. A theoretical calculations based on assumptions were proposed in order to clarify the correlation between the nanowire response and their diameter.

Tin dioxide nanowires were formed by using thermal evaporation and functionalized by Pd nanodots for investigating the effect of nano-additives on NO2 sensing properties. SnO2 nanowires are uniformly functionalized with Pd nanodots by plain micro-drop process of PdCl2. The NO2 sensing characteristics of the Pd-functionalized SnO2 nanowires are compared with those of bare SnO2 nanowires. The results indicate that the concentration of catalytic Pd nanodots plays an important role in the enhancement of NO2 sensing properties. The low concentration of Pd nanodots greatly enhances the sensor response and response time in SnO2 nanowire-based gas sensors. However, extensive addition of Pd into the sensing layer resulted in the degradation of sensing characteristics. Moreover, the SnO2 nanowires functionalized with excessively high concentration of Pd nanodots shows an anomalous behavior in its output.

Since isolates recovered on medium containing-Ficus elastica latex showed good growth on the respective natural rubber than those recovered on Euphorbia pulcherrima or Ficus nitida, 16 of these isolates were selected for further growth experiments on natural rubber to determine their protein content as well as rubber viscosity. Of these, the mesophilic strains Aspergillus terreus AUMC 4682, Aspergillus flavus AUMC 4795 and the thermophilic strain Myceliophthora thermophila AUMC 4653 showed low rubber viscosity and high mycelia protein content indicating high biodegradation ability of rubber. The strains were subjected for further analysis. They showed high ability to degrade poly (cis-1, 4-isoprene) rubber fig. The ability was also determined by measuring the increase in protein content of each fungus (mg g−1 dry wt), reduction in molecular weight (g mol−1) and inherent viscosity (dl g−1). Moreover the degradation was characterized by determining aldehyde or keto group by Schiff reagent and observing the growth using scanning electron microscopy (SEM).

Since isolates recovered on medium containing-Ficus elastica latex showed good growth on the respective natural rubber than those recovered on Euphorbia pulcherrima or Ficus nitida, 16 of these isolates were selected for further growth experiments on natural rubber to determine their protein content as well as rubber viscosity. Of these, the mesophilic strains Aspergillus terreus AUMC 4682, Aspergillus flavus AUMC 4795 and the thermophilic strain Myceliophthora thermophila AUMC 4653 showed low rubber viscosity and high mycelia protein content indicating high biodegradation ability of rubber. The strains were subjected for further analysis. They showed high ability to degrade poly (cis-1, 4-isoprene) rubber fig. The ability was also determined by measuring the increase in protein content of each fungus (mg g−1 dry wt), reduction in molecular weight (g mol−1) and inherent viscosity (dl g−1). Moreover the degradation was characterized by determining aldehyde or keto group by Schiff reagent and observing the growth using scanning electron microscopy (SEM).

The addition of 0.5 mM ascorbic acid (AsA) to the hydroponic growth solution of young soybean cultivars, cvs (Glycine max Exford, high sensitive and G. max Giza 21, low sensitive) under normal growth, conditions provided protection against subsequent salinity stress. This observation was confirmed by fresh and dry matter contents, dose of response, total water content photosynthetic pigments, transpiration rate, AsA contents, membrane stability index, K+ leakage and minerals (Na+, K+ content, translocation, uptake and K+/Na+ ratio). In addition, analysis of antioxidant enzymes showed that AsA pretreatment causes an increase in catalase (EC 1.11.1.6), ascorbate peroxidase (APX) (EC 1.11.1.11) and guaiacol peroxidase (EC 1.11.1.7) activities under salinity stress. The seedlings of two soybean cultivars differing in salt sensitivity were treated with 0.1, 0.2 and 0.4 M NaCl for 3 days.

The presence of the genetic toxic chemicals in the aquatic environment increased. This study aimed using the random amplified polymorphic DNA (RAPD-PCR) assay to investigate the genotoxic effects of 4-nonylphenol in adults and embryos of African catfish Clarias gariepinus. After exposure of adults and embryos to sublethel concentrations of 4-nonylphenol (0, 0.05, 0.08, and 0.1 mg/l) for 15 days, DNA was extracted for RAPD assay. The RAPD pattern from catfish exposed to 4-nonylphenol displayed some changes in polymorphism band patterns including disappearance and appearance of bands. Cluster method was used to indicate the distinct distance between the band patterns of exposed fish and the control. In conclusion, the RAPD-PCR is method can be used as an investigation tools for the evaluation of the genetic damage of the catfish induced by the exposure to 4-nonylphenol.