Fiber-metal laminate composite is made by pasting metal layers and fiber-resin composite together. The metal used is often aluminum and the fiber is Aramid, Carbon or Glass depend on the application. In this study, we have used aluminum-fiber glass laminates (GLARE) due to its vast application because of its high mechanical resistance. At first, the effect of impact energy on fiber-metal composite in low velocity impact was analyzed experimentally. It was concluded that by increasing the primitive energy of the IMPACTOR, composite structure shows more toughness and energy attraction rate. Afterward, by modeling the performed tests in LS-DYNA software, a validation was conducted. Due to the subtle difference between numerical and experimental result, the validation of the modeling was accepted. In the last step, the effect of changing the thickness of layers on a generally fixed thickness composite structure was studied numerically. It was concluded that increasing the thickness of fiber layers and decreasing the thickness of aluminum layers lead to an increase of the collision time span and a decrease of the composite structure toughness.

Introduction: Evaluating the effectiveness of the treatment method is possible when the model has been closer to reality. In experiments that need fixation of the spinal cord, the conventional method is to suspend the rostral and caudal spine via clamps attached to spinous processes. However, the slip and displacement of the spinal cord were high, which can significantly influence the model's outcome. So, this study aims to introduce a new design to stabilize the vertebra completely for the rat spinal cord injury (SCI) model. Methods: Twenty-three female Sprague Dawley rats randomly were assigned to control (intact spinal cord), unstabilized-SCI, and stabilized-SCI groups. Functional recovery was assessed using the Basso Beattie Bresnahan (BBB) test for four weeks. The success rate of the moderate model was calculated based on BBB score in the 7-days post-injury. Then, the spinal cords were evaluated by Luxol Fast Blue and Hematoxylin-Eosin (LFB/HE) staining to show lesion morphology Results: The BBB score of the stabilized-SCI indicated moderate SCI that had a significant difference (P<0. 05) compared to the unstabilized-SCI which showed nonmoderate SCI. The success rate of the moderate model in stabilized-SCI was 80%, whereas in the unstabilized-SCI method was 30%. The LFB/HE staining in stabilized-SCI showed the epicenter's rostral and caudal lesions demyelination. In contrast, in the unstabilized-SCI, demyelination was only detected in the lesion site, and the rostral and caudal spinal columns were intact. Conclusion: The introduced device could make consistent functional deficits and was able to make an effective force to perform the spinal cord injury.

Introduction: The use of standard rodent model, allows for the understanding of neuronal injury physiopathology and helping development of therapeutic strategies. Because of eliminating technical problems, we designed a modified IMPACTOR device with ability to induce different degrees according to kilodyne from very mild to very severe of spinal cord injury (SCI) and traumatic brain injury (TBI) models in rat. Methods: For standardization and determining of optimal performance of the device to induce varying injuries, 47 adult male Wistar rats were used, and 8 different forces were applied in spinal cord and brain tissues. Results: The hematoxylin and eosin and 2, 3, 5-triphenyltetrazolium chloride (TTC) results demonstrated that by increasing the level of forces, histological changes in the spinal cord and brain were significantly enhanced. Different injuries had significant effect on the Basso-Beattie-Brenham and elevated body swing test outcomes, and there were significant differences between groups in comparison with control group. Conclusion: Our results showed that the modified device could be valid to produce precise SCI and TBI models, goal to replicate SCI and TBI in humans as much as possible. However, it might be considered that aspects of SCI and TBI models are complicate and more examination is necessary.

The deposition efficiency and pressure drop of inertial IMPACTOR with variable area has been studied numerically and experimentally. The effect of volumetric flow rate, vertical barrier, oblique barrier and flexible concave plate versus deposition and impaction efficiency and pressure drop is investigated. Numerical simulation is carried out with DPM (discrete phase method) and turbulent model of SST k-ω . To validate the numerical results a special test rig is designed to study the deposition efficiency of engine oil droplets (blow-by) with a diameter of 0. 1 to 6 μ m. Experimental Tests are done in 8, 12, 16 and 20 L/min. To ensure the accuracy of the experimental results, all the tests are repeated at least three times for each volumetric flow rate. Gravimetric method is implemented to calculate the deposition efficiency. According to the results, the deposition efficiency is obtained between 73 and 94 percent for different mentioned IMPACTORs and different volumetric flow rate. The numerical results are confirmed by experimental results. Using the barriers increase the efficiency maximum 6 percent in different volumetric flow rate. The results show that by reducing the distance between the vertical barrier and the outlet of nozzle, the deposition and impaction efficiency are increased. Also, the Concave flexible plate with vertical barrier located at 1 mm from the outlet of nozzle is the most efficient case.

In the process of quality control of pulmonary drug delivery products, aerosolization efficiency is mainly determined using IMPACTORs, e. g. next generation IMPACTOR (NGI). However, particle bounce may interfere with the validity and accuracy of results due to the overestimation of the respirable fraction. It is suggested that the coating of IMPACTOR’ s stages may prevent the particle bounce. Therefore, coating materials may influence the results of the aerosolization indexes of pulmonary dosage forms. The aim of this study was to investigate if the aerosolization indices are affected differently by using the different coating materials. In this study, the effects of using different materials including Span® 85, Tween® 80, silicon® oil, glycerin and Brij® 35/glycerin mixture recommended for the coating of NGI stages on the aerosolization indices such as fine particle fraction, fine particle dose, mass median aerodynamic diameter, and geometric standard deviation of salbutamol emitted from a commercial metered dose inhaler (MDI), were assessed. Three statistically different results were obtained on using Tween® 80, Span® 85 and silicon oil, and glycerin and Brij® 35/glycerin mixture. It can be concluded that the type of coating material influenced the aerosolization indices of the examined MDI in NGIs.

This study presents the response of twill glass fiber-epoxy laminates enhanced with different nanomaterials (0. 5 wt%) subjected to high-velocity ice impact. The mechanical properties and ice impact performance of specimens were evaluated on different nanomaterials. The effect of the amine-functionalized carbon nanotubes (AFCNTs) on the ice impact behaviour was studied. To investigate the effect of manufacturing method of nano-glass fiber-epoxy laminated plates, hand lay-up and vacuum infusion process (VIP) were employed, and ice impact resistance of the laminated plates was measured by high-velocity (138 m/s) ice impact tests. The VIP method resulted in inappropriate distribution of nanomaterial into epoxy resin, therefore hand lay-up method was selected for manufacturing of the laminated plates reinforced with nanomaterials. Moreover, 9. 2 g cylindrical ice IMPACTOR with flat, hemispherical and conical tips was manufactured to investigate the effect of ice IMPACTOR nose shapes in the same level of energy (96. 7 J). The failure modes and damage area were reported for all specimens. Scanning electron microscopy was utilized to describe morphology of nanomaterials on laminated plates. The results showed that the damage formation in specimens depends on the type of nanomaterial used. It was concluded that the multi-walled carbon nanotubes improved the ice impact response by restricting the damage area in laminated plates. A significant decrease in the absorbed energy capability of specimen with AFCNTs was observed under ice impact loading. The conical ice projectile provided a lower level of damage compared to the hemispherical and flat ice projectiles.