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Highlights • Some flexible and waterproof polymeric sheets are developed for EM wave absorption. • Novel polymeric matrix promotes the mechanical and EM wave absorbing properties. • Because of the novel matrix, the amount of fillers is reduced, significantly. • The thickness and density of the sheets are 1 mm and ≈2 gr/cm3, respectively. • The sheets show a remarkable thermal stability and the elongation. Abstract In this work, electromagnetic (EM) wave absorbing properties of polypyrrole/silicone rubber (PP-SI) filled nano-carbon and carbonyl iron (CI) nanocomposites have been investigated in the X-band. The PP-SR matrix was provided by the incorporation of polypyrrole and liquid silicone rubber in the ratio of 10:90. The PP-SR serves not only as a matrix but also promotes the flexibility and EM wave absorption of the nanocomposite sheets. In the present research, the chemical, morphology, thermal, wetting, absorption, and mechanical properties of the EM wave absorber sheets are investigated. The EM wave absorber sheet with 3 wt% nano-carbon and 37 wt% CI and a thickness of 1 mm, exhibits a minimum reflection loss around −13 dB at 10.27 GHz. The absorber sheet with an elongation of 520% could be qualified as a superior elastic sheet. The specimen represents higher thermal stability compared with pure SR, and the contact angle of the sheet proved that their surface should be hydrophobic. [ABSTRACT FROM AUTHOR]

The semi real-time observations of oil-in-water emulsification process in a Kenics static mixer were performed using a novel in situ visualization system. The homogenization processes and emulsion characteristics were analyzed using images taken periodically in fixed time intervals during the emulsification process. Morphological evolution of droplets was monitored and the mechanism of droplet formation was studied, both experimentally and theoretically. A wide range of dispersed phase concentration as well as surfactant concentration were used in the experiments and their impacts on emulsion characteristics were determined. Different droplet formation mechanisms occurred during the experimental results are presented. The relationship between droplet sizes, flow rate, surfactant concentration, and other impact factors was visually shown, and their role in controlling the emulsification process was revealed. The minimum droplet size obtained from the dispersed phase in emulsions was shown to be perfectly monitored and controlled by this technique. [ABSTRACT FROM PUBLISHER]

Our investigation was designed to assess the saccular function of the vestibular system upon postural control dysfunction amongst children with spastic cerebral palsy (CP) using recording of cervical vestibular evoked myogenic potentials (cVEMPs), as well as to compare such findings with those in healthy subjects. Sixty two-children (aged 7-12 years) were enrolled and assigned to two groups. There were 31 cases of spastic CP with the functional levels of I or II according to the Gross Motor Function Classification System in the patient group and 31 aged-matched healthy children as controls. The examined parameters were the latencies of the P and N waves, P-N peak-to-peak amplitude, amplitude asymmetry ratio (AAR), and the cVEMP threshold. The cVEMP responses were recorded in 93.5% of cases in the CP group and in all healthy subjects. Only 51.6% of the CP-group cases were within the normal AAR spectrum range. There were significant differences between the two groups with regard to the N wave latency ( P < 0.001), P-N wave amplitude ( P < 0.001), and cVEMP threshold ( P<0.05). The significant difference in the cVEMP measured values between the CP cases and healthy controls may be attributed to a motor development delay and deficits in the vestibulo-collic reflex pathway. Our findings suggest that cVEMP recording may be considered an auxiliary tool for the assessment of the vestibular system in children with spastic CP. Such a test is expected to help more adequate planning for interventions. [ABSTRACT FROM AUTHOR]