This paper presents an idea of using carbonized electrospun Polyacrylonitrile (PAN) fibers as a sensor material in a structural health monitoring (SHM) system. The electrospun PAN fibers are lightweight, less costly and do not interfere with the functioning of infrastructure. This study deals with the fabrication of PAN-based nanofibers via electrospinning followed by stabilization and carbonization in order to remove all non-carbonaceous material and ensure pure carbon fibers as the resulting material. Electrochemical impedance spectroscopy was used to determine the ionic conductivity of PAN fibers. The X-ray diffraction study showed that the repeated peaks near 42° on the activated nanofiber film were α and β phases, respectively, with crystalline forms. Contact angle, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR) were also employed to examine the surface, thermal and chemical properties of the carbonized electrospun PAN fibers. The test results indicated that the carbonized PAN nanofibers have superior physical properties, which may be useful for structural health monitoring (SHM) applications in different industries.

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Quantity and quality of irrigation water are considered the most imperative limiting factors for plant production in arid environment. Adoptions of strategies can minimize crop water consumption while nonexistent yield reduction is considered challenge for scholars especially in arid environment. Grafting is regarded as a promising tool to avoid or reduce yield loss caused by abiotic stresses. Tomato ( Mill.), commercial cultivar Faridah was grafted on Unifort rootstock and grown under regulated deficit irrigation (RDI) (100%, 80% and 60% ETc), using two types of irrigation water, fresh (EC = 0.86 dS/m) and brackish (EC = 3.52 dS/m). The effects of grafting and RDI on water use efficiency, vegetative growth, yield, fruit quality were investigated. Plant vegetative growth was reduced under water and salinity stresses. Grafting the plant significantly improves the vegetative growth under both conditions. The results showed that crop yield, Ca and K were considerably increased in grafted tomato compared to non-grafted plants under water and salinity stresses. Grafted tomato plants accumulated less Na and Cl, especially under high levels of salinity compared to non-grafted plants. Grafting tomato plants showed a slight decrease on the fruit quality traits such as vitamin C, titratable acidity (TA) and total soluble solids (TSS). This study confirmed that grafted tomato plants can mitigate undesirable impact of salt stress on growth and fruit quality.

Summary The recent attention in the applications of the fiber reinforced thermoplastic composite have raised some concerns because of the ability and performance of the fiber reinforced thermoplastic composite after long‐term exposures to environmental weathering (e.g., UV radiation, moisture, and oxygen). This weathering can be very destructive to the thermoplastic polymers; hence, a systematic study of the UV radiation effects on the properties of fiber‐reinforced thermoplastic composite is crucial for industrial applications. The major objective of the project was to study the correlation between thermoplastic fabrication parameters and the final properties of composites. In this study, carbon fiber (CF) reinforced polyphenylene sulfide (PPS) thermoplastic composites were manufactured using high temperature press after optimizing the parameters. Subsequently, the effects of long‐term UV exposures on the thermal and mechanical properties of CF/PPS thermoplastic composites were investigated in detail. The test results showed that the correlation between the processing parameters and the physical properties of the laminate composites were in all good agreements. The test results also revealed a significant decrease in the glass transition temperature, as well as storage modulus, and tensile strengths. Furthermore, short (200 hrs) and long (300 hrs) term UV exposures changed various thermal and mechanical properties of the thermoplastic PPS composites. This study can provide some preliminary knowledge to engineers and scientists in the field and develop new set of structural composites.

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The effect of a hydrophilic polymer (Broadleaf P4®; HP) on growth of cucumber seedlings (Cucumis sativus L.) was investigated. Furthermore, the efficiency of HP to absorb water over a period of time was studied. Predetermined amounts of HP (0.0%, 0.1%, 0.2%, 0.3%, and 0.4% dry-weight basis) were mixed with moderately calcareous sandy loam soil in pots. At the end of the first experiment (42 days), the growth of the seedlings was recorded, as well as the maximum soil water-holding capacity (WHC). The same pots were left for a drying period ranging from 2 to 5 months and then used for another four successive experiments. Soil WHC increased significantly with increasing level of HP, but decreased after each experiment. After five experiments, the WHC had decreased 17.3% and 27.8% where HP was added at the rate of 0.1% and 0.4%, respectively. The bulk density of soils decreased significantly with addition of HP and had increased after five growing experiments at each HP rate. Cucumber seedling growth was stimulated by addition of the polymer. The greatest vegetative growth, expressed as leaf area and shoot fresh and dry weights, was observed at 0.3% HP in the first and second experiment, but at 0.4% in the third and fourth.