A general extrudate bulk density model for both twin-screw and single-screw extruder extrusion cooking processes

Effects of extrusion parameters and raw materials on extrudate expansion are respectively investigated in a twin-screw extruder and a single-screw extruder extrusion cooking experiments for fish feed, wheat, and oat & wheat mixture processing. A new phenomenological model is proposed to correlated extrudate bulk density, extrusion parameters and raw material changes based on the experimental results. The average absolute deviation (AAD) of the correlation is 2.2% for fish feed extrusion in the twin-screw extrusion process. For the single-screw extrusion process, the correlation AAD is respectively 3.03%, 5.14% for wheat and oat & wheat mixture extrusion; and the correlation AAD is 6.6% for raw material change effects. The correlation results demonstrate that the proposed equation can be used to calculate extrudate bulk density for both the twin-screw extruder and the single-screw extruder extrusion cooking processes

The utilization of bridgehead intermediates in organic synthesis

Bridgehead intermediates have only recently been employed in organic synthesis. This study was undertaken to further explore and broaden their usefulness. Reaction of 9-oxabicyclo(3.3.1) octane mesylates with Lewis acids gave bridgehead oxonium ions which could be reacted with substituted benzenes. Bridgehead sulfoxides were reacted under a variety of conditions to provide bridgehead intermediates. Thermal conditions gave a bridgehead enone that underwent an interesting rearrangement. Reaction with trifluoroacetic anhydride provided the first example of a bridgehead Pummerer reaction. Base promoted elimination afforded a bridgehead enone which was trapped by ammonia

The application of alternating-direction implicit methods to the space-dependent kinetics equations

Cover title"MIT-3903-3."Originally presented as the first author's thesis (Ph. D.), M.I.T. Dept. of Nuclear Engineering, 1969Includes bibliographical references (leaves 54-55)Prepared under U.S. Atomic Energy Commission AT(30-1) 390

Together: Preparing Christian Educators for the Future

Since 1959, the Lutheran Church–Missouri Synod (LC-MS) has been training Christian educators entering the profession that eventually came to be called the Director of Christian Education (DCE). The chapters of this book compile topics of interest to both practicing Christian educators and those studying to become Christian educators. Some chapters summarize research about DCEs and the DCE experience while others share years of personal experience as a DCE within a congregation

Adventure or amusement? Image and identity challenges for the aerial adventure industry and implications for positioning and policy

This paper seeks to address the changing image and identity of the aerial adventure industry as it becomes increasingly commercialized, which has led to uncertainty over its positioning within either adventure tourism or amusement rides. Such a positioning is critical in order to mitigate the problems caused by an inappropriate identification and image that contributes to poor inspections, poor procedures and policies, and ultimately, poor perceived risks and safety. In an industry where one serious injury impacts all operators, it is essential for all stakeholders to have collective “buy in” to effective policies that are standardized across the entire industry. The current identity confusion has merely led to misconceptions from public stakeholders. Through a qualitative case-study, this paper finds that aerial adventure parks share characteristics with adventure tourism and amusement rides and so resembles a hybrid. This is largely due to the presence of inherent risk and the role of the participant, both of which are less present on amusement rides. The paper therefore calls for state agencies to identify the activity as a stand-alone activity and for the subsequent regulations and policies to reflect this hybrid status

Quantum Degenerate Mixture of Ytterbium and Lithium Atoms

We have produced a quantum degenerate mixture of fermionic alkali 6Li and bosonic spin-singlet 174Yb gases. This was achieved using sympathetic cooling of lithium atoms by evaporatively cooled ytterbium atoms in a far-off-resonant optical dipole trap. We observe co-existence of Bose condensed (T/T_c~0.8) 174Yb with 2.3*10^4 atoms and Fermi degenerate (T/T_F~0.3) 6Li with 1.2*10^4 atoms. Quasipure Bose-Einstein condensates of up to 3*10^4 174Yb atoms can be produced in single-species experiments. Our results mark a significant step toward studies of few and many-body physics with mixtures of alkali and alkaline-earth-like atoms, and for the production of paramagnetic polar molecules in the quantum regime. Our methods also establish a convenient scheme for producing quantum degenerate ytterbium atoms in a 1064nm optical dipole trap.Comment: 4 pages, 3 figure

Investigating the Social and Temporal Aspects of Children’s Physical Activity Games

There are a variety of fitness technologies such as activity trackers, exergames and mobile applications available to promote physical activity. Based on our previous research, we found that children prefer having social interaction, a narrative and flexibility while interacting with such technologies. Other research has shown that persuasive displays encouraged adults towards physical activity. In this research, we present the initial results from a user study conducted on 16 children (ages 6-11) who used the Kidfit suite, a collection of mobile applications that combine and utilize the elements found from previous research to promote activity in children

\u27Invisible Whispering\u27: Instant Messaging in Meetings

We use Goffman’s characterization of front and backstage interaction practices to analyze how the use of instant messaging in both face-to-face and technology-mediated meetings alters the spatial, temporal, and social configurations of meetings. In an interview study of workers in two organizations, we found that workers used instant messaging during face-to-face meetings and telephone conference calls (1) to participate concurrently in front and backstage interactions, (2) to participate in multiple, concurrent, backstage conversations, and (3) to manage and influence front stage activities through concurrent backstage conversations. These interactions would be either physically impossible or socially constrained without the use of instant messaging. We draw on psychology, GSS, and communication studies to consider the implications for group work

Sympathetic cooling in an optically trapped mixture of alkali and spin-singlet atoms

We report on the realization of a stable mixture of ultracold lithium and ytterbium atoms confined in a far-off-resonance optical dipole trap. We observe sympathetic cooling of 6Li by 174Yb and extract the s-wave scattering length magnitude |a6Li-174Yb| = (13 \pm 3)a0 from the rate of inter-species thermalization. Using forced evaporative cooling of 174Yb, we achieve reduction of the 6Li temperature to below the Fermi temperature, purely through inter-species sympathetic cooling.Comment: 4 pages, 3 figure