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The investigation of design parameters is very helpful for optimizing the capacity of an electrochemical cell, which can be done by both experimental and numerical methods. In this study, a lead-acid battery has been simulated numerically using the CFD commercial software package FLUENT. The governing equations, including conservation of charge in solid and liquid phases and conservation of species, are solved by developing several user defined functions (UDF). The effect of some basic parameters such as electrode porosity, discharge current density, and width of the electrodes and separator on the cell voltage behavior of a lead-acid battery is investigated. It has been shown that increasing the width and porosity of separator has both positive and negative effects on the performance parameters of battery. Furthermore, a thicker PbO 2 electrode has a more pronounced effect than a thicker Pb one.

Blanking is one of the high speed processes to produce flat products from sheets economically. In order to expand this process to new materials, the blanking of polyvinyl chloride (PVC)/fiberglass thermoplastic composite laminates and composite/aluminum hybrid laminates was investigated. The laminates were produced by the film stacking procedure and then blanked by circular die and punches. The blanking process was done in two levels of clearance including 4% and 8% of the laminates thickness, two levels of punch speed including 40 mm/min and 200 mm/min and at two levels of temperature (room temperature and 80 °C) for both composite and hybrid laminates. The effects of the parameters on the maximum blanking force, cutting energy, and quality and precision of sheared edges were studied. Cutting mechanism for blanking in different conditions was explained. It was concluded that at room temperature, blanked composite and hybrid laminates had a high quality of sheared edges but at elevated temperature, although the maximum blanking force was reduced, the quality of sheared edge was reduced significantly.

Background: Polycystic ovary syndrome (PCOS) is a heterogeneous medical condition with a cluster of metabolic and endocrine disorders including dyslipidemia, insulin resistance, and hyperandrogenism. Objective: The present study aimed to determine the effects of single-dose and cosupplementation of vitamin D (vit D) and omega-3 (O3) on anthropometric and several biochemical factors in women with PCOS. Materials and Methods: In this double-blind, randomized clinical trial, 80 PCOS women referred to Shahid Motahhari Clinic, Shiraz, Iran, from April to October 2017 were studied in 4 groups (n = 20/each) for 8 wk. The placebo group received the placebo capsule (paraffin oil); 1 weekly and 2/daily; the vit D group received vit D (50,000 IU/weekly) + 2 placebo capsules daily, O3 group, 2, O3 capsules daily + 1 placebo capsule weekly, and vit D + O3 (50000 IU/weekly vit D + 2, O3 capsules daily). Before and after 8 wk of intervention, height, weight, body mass index, waist circumference, triglycerides, total cholesterol (TC), high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, fasting blood sugar, homeostasis model of insulin resistance index, and sex hormone binding globulin were compared between groups. Results: The significant reduction was detected in serum triglyceride (p = 0.002), TC (p = 0.04), fasting blood sugar (p = 0.02), insulin (p = 0.001), and homeostasis model of insulin resistance index (p = 0.001) concentrations in all vit D, O3, and vit D + O3 supplemented groups compared to the placebo group. Furthermore, in comparison with the placebo group, a significant increase was observed in serum sex hormone binding globulin levels after vit D, O3, and vit D + O3 treatments. Nevertheless, no significant changes were observed in serum highdensity lipoprotein cholesterol, low-density lipoprotein cholesterol, and anthropometric indices in all treated participants. Conclusion: The current study indicated that single dose and co-supplementation of vit D and O3 for 8 wk was associated with beneficial effects on serum triglyceride, TC, insulin, and sex hormone binding globulin concentrations among women suffering from PCOS. Key words: Polycystic ovary syndrome, Vitamin D, Omega-3 fatty acid, Insulin, Sex hormone- binding globulin.

Semi-crystalline thermoplastic-based composite laminates and fiber metal laminates have a narrow forming temperature window, which limits formability of these products. The intention of this study was investigation of non-melting amorphous polyvinyl chloride as a proper matrix to increase the formability and forming temperature window of these products. For this, [45/−45] and [0/90] layups of polyvinyl chloride-based composite laminates and fiber metal laminates were produced using the film-stacking procedure and later press formed into channel sections at six temperatures in the range of 80 to 200 °C. The effects of the layups and forming temperatures on the forming loads and spring back of the formed profiles were measured, and their effects on the fiber buckling, wrinkling, and delamination of the profiles were evaluated using optical microscope images. The effects of layups and forming temperatures on the deformation mechanisms were also analyzed using the grid strain analysis method. Of the fiber metal laminates, 160 °C was found as the minimum forming temperature, and for the composite laminates, 120 and 160 °C were found as the minimum proper forming temperatures of [45/−45] and [0/90] layups, respectively. Finally, the forming temperature windows and formability of polyvinyl chloride matrix composite laminates and fiber metal laminates were found higher than semi-crystalline matrices.

A series of freeze-thawed, polyvinyl alcohol nanocomposite hydrogels were prepared using various loading levels (0-15 wt%) of hydrophilic natural Na-montmorillonite nanoclay. The morphology of nanocomposite hydrogels, their dehydration kinetics at different temperatures and the effect of Na-montmorillonite on the gelation process were investigated. The results showed a partially exfoliated morphology for the prepared nanocomposite hydrogels. Also by increasing the amount of nanoclay incorporated into the specimens, the gel fraction values of nanocomposite hydrogels were increased. According to the dehydration tests, the dehydration rates of nanocomposite hydrogels exhibited an inverse dependency on the nanoclay loading level and a direct dependency on the dehydration temperature. Finally, it was concluded that the dehydration mechanism of all specimens prepared is non-Fickian at 20 °C, while it is Fickian at 37 °C and 55 °C. [PUBLICATION ABSTRACT]