Rotation and activity in the solar-type stars of NGC 2547

We present high resolution spectroscopy of a sample of 24 solar-type stars in the young (15-40 Myr), open cluster, NGC 2547. We use our spectra to confirm cluster membership in 23 of these stars, determine projected equatorial velocities and chromospheric activity, and to search for the presence of accretion discs. We have found examples of both fast (vsini>50kms) and slow (vsini<10kms) rotators, but find no evidence for active accretion in any of the sample. The distribution of projected rotation velocities is indistinguishable from the slightly older IC 2391 and IC 2602 clusters, implying similar initial angular momentum distributions and circumstellar disc lifetimes. The presence of very slow rotators indicates that either long (10-40 Myr) disc lifetimes or internal differential rotation are needed, or that NGC 2547 (and IC 2391/2602) were born with more slowly rotating stars than are presently seen in even younger clusters and associations. The solar-type stars in NGC 2547 follow a similar rotation-activity relationship to that seen in older clusters. X-ray activity increases until a saturation level is reached for vsini>15-20kms. We are unable to explain why this saturation level, of log (L_x/L_bol)~-3.3, is a factor of two lower than in other clusters, but rule out anomalously slow rotation rates or uncertainties in X-ray flux calculations.Comment: Accepted by MNRA

Theoretical Investigation of Internal Rotation Barriers of 4-(Dimethylaminocinnamaldehyde)

Theoretical study on 4-dimethylaminocinnamaldehyde was done analyzing the barriers of rotation and interpretation of its Raman spectrum. B3LYP Density functional with basis sets up to 6-31G ** with additional f and d functions on C, N, O, and H respectively, calculations were performed. Results indicate trans conformation of the molecule had the lowest energy. Vibrational modes of interest were noted around 500, 1192, 1263, 1316, 1547, and 1608 cm-1. Observed strong enhancement at noted frequencies can be further studied in determining the molecule with other subatomic particles (Ag colloids)

Page turning system

A device for holding reading materials for use by readers without arm mobility is presented. The device is adapted to hold the reading materials in position for reading with the pages displayed to enable turning by use of a rubber tipped stick that is held in the mouth and has a pair of rectangular frames. The frames are for holding and positioning the reading materials opened in reading posture with the pages displayed at a substantially unobstructed sighting position for reading. The pair of rectangular frames are connected to one another by a hinge so the angle between the frames may be varied thereby varying the inclination of the reading material. A pair of bent spring mounted wires for holding opposing pages of the reading material open for reading without substantial visual interference of the pages is mounted to the base. The wires are also adjustable to the thickness of the reading material and have a variable friction adjustment. This enables the force of the wires against the pages to be varied and permits the reader to manipulate the pages with the stick

Compliant joint

A compliant joint is provided for prosthetic and robotic devices which permits rotation in three different planes. The joint provides for the controlled use of cable under motion. Perpendicular outer mounting frames are joined by swaged cables that interlock at a center block. Ball bearings allow for the free rotation of the second mounting frame relative to the first mounting frame within a predetermined angular rotation that is controlled by two stop devices. The cables allow for compliance at the stops and the cables allow for compliance in six degrees of freedom enabling the duplication or simulation of the rotational movement and flexibility of a natural hip or knee joint, as well as the simulation of a joint designed for a specific robotic component for predetermined design parameters

User friendly joystick

A joystick control device having a lower U-shaped bracket, an upper U-shaped bracket, a handle attached to the upper U-shaped bracket, with the upper U-shaped bracket connected to the lower U-shaped bracket by a compliant joint allowing six degrees of freedom for the joystick. The compliant joint consists of at least one cable segment affixed between the lower U-shaped bracket and the upper U-shaped bracket. At least one input device is located between the lower U-shaped bracket and the upper U-shaped bracket