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Nanofibers of polyvinylidene fluoride (PVDF) were prepared using solutions of PVDF with acetone and dimethylacetamide. The solutions were prepared at different concentrations (18, 21.5, and 25% wt) of PVDF. The nanofiber membranes were produced by using the Forcespinning™ method. Parameters such as the orifice size and spinneret angular velocity were varied. The produced membranes were characterized using scanning electron microscopy, differential scanning calorimetry, and X‐ray diffraction to determine the effect of varying parameters in the Forcespinning™ process on fiber diameter, bead formation, thermal stability, polymorphism, and morphology of the fibers and overall structure of the membrane. It was observed that polymer concentration played a key role in fiber and bead formation; at higher concentrations (such as 25 wt%), the fiber diameter increased but the bead formation decreased. The prepared composite membranes have potential applications on separators for Li‐ion batteries, ultra filtration membranes, and proton conductivity membranes for fuel cells applications. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers

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Statics is one of the first fundamental engineering courses in almost all engineering fields; it is a challenging course prerequisite for several engineering mechanics and design courses. Students in Statics need to acquire a strong foundation of long-lasting knowledge and deep understanding of concepts, while mastering adequate techniques and procedures that are essential to analyze and solve engineering problems. However, many engineering programs are facing serious difficulties in promoting student academic success in Statics. In the Mechanical Engineering Department at the University of Texas-Pan American (UTPA), the average passing rate in Statics during the past ten regular semesters is 60.7%, with about 14.3% students dropping the course, and about 25.0% getting D or F grades. Students drop or quit the course due to different circumstances at several stages along the semester. Some common documented reasons for students to drop the course are: deficiency in math (algebra and trigonometry), poor study skills and habits, work to support themselves and their families, taking too many courses, and lack of commitment and discipline, among other. For students that stay in the course until the end of the semester, there is a strong correlation among exam and course grades and the quality time and work dedicated to complete and submit homework. Hence, online formative assessments were developed and implemented to promote student knowledge retention and integration. Online assessments motivate students to use what they learn in one part of the course in subsequent topics to reinforce and integrate knowledge. Furthermore, the formative assessments provide quick feedback to students in topics being studied and alert them about the need to seek additional assistance. In addition, the Mechanical Engineering department has recently implemented voluntary weekly recitation sessions for undergraduate courses having high failure rates. Recitation sessions in Statics are about 3 hours a week and they engage students to work in teams of two or three members to solve homework problems that are completed and submitted by the end of the recitation session. The recitation sessions are recommended to all students in the course; but, currently, they are not mandatory because of scheduling difficulties. They might become mandatory for students that are repeating the course, students that did not pass the course pretest at the beginning of the semester, and for students that fail course exams. A teaching assistant coordinates efforts with the course instructor to help students during the recitation sessions. It is argued that the described activities have increased and will continue to increase student engagement in learning and their persistence to pass the course. Preliminary assessment results show promising accomplishments in addressing knowledge and student retention and engagement in Statics.