A Novel Laboratory Course on Advanced Chemical Engineering Experiments

The chemical engineering curriculum in the United States has trained generations of technical experts who have successfully optimized chemical processes and products once they entered the chemical industry. The U.S. chemical industry, however, has entered a critical stage in which it must be able to create new and differentiated value through technical innovations that arc essential for long-term survival. This innovation process will require new skills that go far beyond the traditional expertise for the optimization of tasks possessed by young chemical engineers. The innovators must be able to identify new opportunities, explore the boundaries of technology, evaluate critical issues, develop and implement technologies, and communicate effectively with scientists and engineers from other disciplines. Therefore, one of the most important educational tasks of a modern university, in combination with a strong theoretical foundation, is to challenge students in laboratory courses to think, explore, hypothesize, plan, solve, and evaluate. The typical sequence of laboratory skills development stops short of introducing young engineers to the most critical aspects of experimental work. Chemical engineers usually begin developing their laboratory skills in chemistry courses, where experiments are closely managed. At this early stage in their development, students follow detailed instructions and learn basic principles by observing the results. In the undergraduate engineering laboratory course (the unit operations lab ), students have more freedom in experimental design but still have well-defined objectives and manipulate equipment someone else has set up. It is rare, however, for undergraduate students to be taught how to create new experiments. It is also rare for undergraduate students, and hence beginning graduate students, to have an appreciation for the care, planning, design, and testing required to produce equipment that will give reliable and useful results. Even such simple issues as leak testing or adapting analytical devices to new tasks are outside most students* experience. Even more important is an absence of opportunities to learn how the lessons learned from the failure of an approach can be fed back into the empirical process to seed the finally successful idea. All these skills require more creative freedom than is usually allowed in a well-structured laboratory course. In the novel laboratory teaching approach described here, we try to provide students with a learning environment that allows them to develop advanced experimental skills that are necessary for success in research and development environments

The effect of force-field parameters on properties of liquids:Parametrization of a simple three-site model for methanol

A simple rigid three-site model for methanol compatible with the simple point charge (SPC) water and the GROMOS96 force field is parametrized and tested. The influence of different force-field parameters, such as the methanol geometry and the charge distribution on several properties calculated by molecular dynamics is investigated. In particular an attempt was made to obtain good agreement with experimental data for the static dielectric constant and the mixing enthalpy with water. The model is compared to other methanol models from the literature in terms of the ability to reproduce a range of experimental properties.<br/

МНОГОФАЗНО-ОДНОФАЗНыЕ РЕВЕРСИВНыЕ ЭЛЕКТРОМАШИННО-ВЕНТИЛЬНыЕ ПРЕОБРАЗОВАТЕЛИ БЕСКОНТАКТНыХ МАШИН ДВОЙНОГО ПИТАНИЯ

Розглянуто процеси в багатофазно-однофазних реверсивних електромашинно-вентильних перетворю- вачах безконтактних машин подвійного живлення. Рассмотрены процессы в многофазно-однофазных реверсивных электромашинно-вентильных преобра- зователях бесконтактных машин двойного питания

Book Reviews

Book Review 1Book Title: Modern Coloproctology: Surgical Grand Rounds from St Mark's HospitalBook Authors: Robin Phillips &amp; John Northover (Eds.)pp. 195. illustrated. London: Edward Arnold. 1993. ISBN 0-340-55258-1Book Review 2Book Title: Diagnostic Molecular Pathology: A Practical Approach. Vol. I &amp; IIBook Authors: C.S. Herringron &amp; J.O'D. McGee (Eds.)Pp. Vol. I xviii + 270; Vol. II xvi + 217. Cape Town: Oxford University Press. 1992. ISBN Vol. I 0-19-963236-7, Vol. II 0-19-963238-3.Book Review 3Book Title: Training Therapy: Prophylaxis and RehabilitationBook Authors: Rolf Gustavsen &amp; Renate Streeck2nd revised ed. Pp. viii + 230. Illustrated. Stuttgart: George Thieme Verlag. 1993. ISBN 3-13-672502-6.Book Review 4Book Title: Handbook of Bereavement: Theory, Research and InterventionBook Authors: Margaret S. Stroebe, Wolfgang Stroebe &amp; Robert O. Hansson (Eds.)Pp. xii + 546. Cambridge: Cambridge University Press. 1993. ISBN 0-521-39315-9 hardback, ISBN 0-52144853-0 paperback.Book Review 5Book Title: Atlas of Gynecologic PathologyBook Authors: J. Donald Woodruff, Teresita L. Angruaco &amp; Tim H. Pannley (Eds.)pp.321. New York: Raven Press. 1993. ISBN 0-7817-0056-6.Book Review 6Book Title: Our Planet, Our Health: Report of the WHO Commission on Health and EnvironmentBook Author: World Health OrganisationPp. 282. Geneva. 1992. ISBN 92-4-156148-3.Book Review 7Book Title: Neonatal Tetanus Elimination Field Guide. Technical Paper No 35Book Author: Pan American Health OrganisationPp. v +37. Washington: Pan American Health Organisation. 1993. ISBN 92-75-13035-3

20 K Helium Refrigeration System for NASA-JSC Chamber-A

A new 20 K helium refrigerator installed at NASA Johnson Space Center's Space Environment Simulation Laboratory (SESL) was successfully commissioned and tested in 2012. The refrigerator is used to create a deep space environment within SESL s Chamber A to perform ground testing of the James Webb Space Telescope. The chamber previously and currently still has helium cryopumping panels (CPP) and LN2 shrouds used to create Low Earth Orbit environments. Now with the new refrigerator and new helium shrouds (45 x 65 ) the chamber can create a deep space environment. The process design, system analysis, specification development, and commissioning oversight were performed by the cryogenics department at Jefferson Labs, while the contracts and system installation was performed by the ESC group at JSC. Commissioning data indicate a inverse coefficient of performance better than 70 W/W for a 18 KW load at 20 K (accounting for liquid nitrogen precooling power) that remains essentially constant down to 1/3 of this load. Even at 10 percent of the maximum capacity, the performance is better than 140 W/W at 20K. The refrigerator exceeded all design goals and demonstrated the ability to support a wide load range from 10kW at 15 K to 100 kW at 100K. The refrigerator is capable of operating at any load temperature from 15K to ambient with tight temperature stability. The new shroud (36 tons of aluminum) can be cooled from room temperature to 20 K in 24 hours. This paper will outline the process design and commissioning results

CO adsorption on neutral iridium clusters

The adsorption of carbon monoxide on neutral iridium clusters in the size range of n = 3 to 21 atoms is investigated with infrared multiple photon dissociation spectroscopy. For each cluster size only a single v(CO) band is present with frequencies in the range between 1962 cm-1 (n = 8) and 1985 cm-1 (n = 18) which can be attributed to an atop binding geometry. This behaviour is compared to the CO binding geometries on clusters of other group 9 and 10 transition metals as well as to that on extended surfaces. The preference of Ir for atop binding is rationalized by relativistic effects on the electronic structure of the later 5d metals

Commissioning of a 20 K Helium Refrigeration System for NASA-JSC Chamber A

A new 20 K helium refrigerator installed at NASA Johnson Space Center s Space Environment Simulation Laboratory (SESL) was successfully commissioned and tested in 2012. The refrigerator is used to create a deep space environment within SESL s Chamber A to perform ground testing of the James Webb Space Telescope (JWST). The chamber previously and currently still has helium cryo-pumping panels (CPP) and liquid nitrogen shrouds used to create low earth orbit environments. Now with the new refrigerator and new helium shrouds the chamber can create a deep space environment. The process design, system analysis, specification development, and commissioning oversight were performed by the cryogenics department at Jefferson Lab, while the contracts and system installation was performed by the ESC group at JSC. Commissioning data indicate an inverse coefficient of performance better than 70 W/W for a 18 kW load at 20 K (accounting for liquid nitrogen pre-cooling power) that remains essentially constant down to one third of this load. Even at 10 percent of the maximum capacity, the performance is better than 150 W/W at 20 K. The refrigerator exceeded all design goals and demonstrated the ability to support a wide load range from 10 kW at 15 K to 100 kW at 100 K. The refrigerator is capable of operating at any load temperature from 15 K to ambient with tight temperature stability. The new shroud (36 tons of aluminum) can be cooled from room temperature to 20 K in 24 hours. This paper will outline the process design and commissioning results