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Methanation catalysts were prepared by flame-spraying aluminum onto a nickel surface followed by heating to form a Raney-type alloy and then activating with a caustic leach. Different alloying temperatures from 400 to 950 °C were employed. A maximum in methanation activity occurred for a sample alloyed at 725 °C. Little alloying occurred for catalysts preheated at 400 °C whether for 1 h or for 910 h and low activities were obtained. This indicates that active catalysts were not formed by a slow diffusion process at a temperature that might be used for methanation. It was shown that alloying takes place very quickly near or above the melting point of aluminum and that no more than 10 min is required for the heating process. Methanation activity and product selectivity were determined using a pulse microreactor by passing 3:1 synthesis gas over each sample at temperatures ranging from 300 to 400 °C. For all catalysts, the conversion of CO increased with increasing reactor temperature. The selectivity to methane was high (>88%) regardless of reactor temperature, but the selectivity to C02 increased, while that to C2H6 decreased as the temperature was raised from 300 to 400°C. A thermally deactivated sample was completely reactivated by repeating three steps used in the original preparation. X-Ray diffraction and microscopic analyses data show a correlation between the NiAI3 content in the unleached alloy and the methanation activity of the leached catalyst.

F or the past two years, the Eoundations in Physics and Mathematics (FPM) summer program has been held at Indiana University in order to fulfill two goals: provide additional physics and mathematics instruction at the high school level, and provide physics graduate students with experience and autonomy in designing curricula and teaching courses. In this paper we will detail changes made to the program for its second year and the motivation for these changes, as well as implications for future iterations of the program. We gauge the impact of the changes on student performance using pre-/post-test scores, student evaluations, and anecdotal evidence. These data show that the program has a positive impact on student knowledge and this impact was greater in magnitude in the second year of the program. We attribute this improvement primarily to the inclusion of more inquirydriven activities. All activities, worksheets, and lesson plans used in the program are available online.D espite the increased availability of math and physics resources at the secondary level via the Internet, face-to-face interactions with qualified math and physics instructors beyond the allotted class time can be difficult to find. Educational opportunities outside the classroom, such as tutoring, are not available in all areas and the costs of these services are prohibitively high for many students. Similarly, quality teaching and curriculum development experiences for graduate students are lacking in many graduate programs. In an attempt to address these deficiencies, we created and implemented a summer math and physics program for local high school students in the summer of 2010.We were unable to find a description in the literature of a short summer program (-12 hours) that emphasized preparation for upcoming high school courses. Other summer programs reviewed in the literature appear to fall into two distinct types. The first type is the so-called "Scientist in the Classroom" program in which scientists or graduate students conduct activities and demonstrations during a short (~1 to 3 day) outreach program in high school classrooms.^ A similar program also involved graduate students participating in high school classroom activities, but involved a longer duration of approximately one semester.^ The other type of summer program lasted for several weeks and involved students traveling to a university where they took part in early research experiences within research laboratories.^'^ It appears that our combination of a university setting, an emphasis on preparation for high school courses, and a relatively short time frame (12 hours) is unique in the literature.

Course outline and suggested topics for research papers.