34,283 research outputs found
Zero gravity liquid transfer screen
A liquid transfer device for use in a zero gravity environment, for transferring liquid from one container to another is described. The device includes a spiral shaped screen type member which is carried in the container for collecting the randomly dispersed liquid and transferring such to an exit port
Floating baffle to improve efficiency of liquid transfer from tanks
When liquid tank is full, baffle is held up against a stop on top of shaft to prevent restriction of flow from outlet. As tank is being emptied, baffle, floating on top of liquid surface, descends with liquid level toward outlet until it reaches its bottom stop. Baffle prevents gas pull-through until practically all liquid is emptied from tank
Geysering inhibitor pipe
Smaller concentric pipe is welded to main pipe beginning above bottom of isolation valve and terminating in storage tank at top. There is continuous circulation of fluid which maintains fluid temperature below boiling temperature of liquid oxygen
Strengthening Trade Adjustment Assistance
More than 40 years ago, Congress established the Trade Adjustment Assistance (TAA) program to provide assistance to workers and firms adversely affected by import competition. The program provides extended income maintenance and training to workers and technical assistance to firms. TAA was expanded in the 1970s and cut back during the 1980s. Provisions included in the Trade Act of 2002 breathed new life into the program. Eligibility criteria were extended to include secondary workers and workers who lose their jobs due to offshore shifts in production. A health insurance tax credit and wage insurance were added to the package of assistance for workers. TAA for Farmers and Fishermen was also created. Congress is currently considering further changes to the program, including covering service workers and expanding the health insurance tax credit and wage insurance. Many believe that expanding TAA is critical to winning congressional support for further trade liberalization.
Phonons in potassium doped graphene: the effects of electron-phonon interactions, dimensionality and ad-atom ordering
Graphene phonons are measured as a function of electron doping via the
addition of potassium adatoms. In the low doping regime, the in-plane carbon
G-peak hardens and narrows with increasing doping, analogous to the trend seen
in graphene doped via the field-effect. At high dopings, beyond those
accessible by the field-effect, the G-peak strongly softens and broadens. This
is interpreted as a dynamic, non-adiabatic renormalization of the phonon
self-energy. At dopings between the light and heavily doped regimes, we find a
robust inhomogeneous phase where the potassium coverage is segregated into
regions of high and low density. The phonon energies, linewidths and tunability
are remarkably similar for 1-4 layer graphene, but significantly different to
doped bulk graphite.Comment: Accepted in Phys. Rev. B as a Rapid Communication. 5 pages, 3
figures, revised text with additional dat
Motor regulation results in distal forces that bend partially disintegrated Chlamydomonas axonemes into circular arcs
The bending of cilia and flagella is driven by forces generated by dynein
motor proteins. These forces slide adjacent microtubule doublets within the
axoneme, the motile cytoskeletal structure. To create regular, oscilla- tory
beating patterns, the activities of the axonemal dyneins must be coordinated
both spatially and temporally. It is thought that coordination is mediated by
stresses or strains, which build up within the moving axoneme, and somehow
regulate dynein activity. While experimenting with axonemes subjected to mild
proteolysis, we observed pairs of doublets associate with each other and form
bends with almost constant curvature. By model- ing the statics of a pair of
filaments, we show that the activity of the motors concentrates at the distal
tips of the doublets. Furthermore, we show that this distribution of motor
activity accords with models in which curvature, or curvature-induced normal
forces, regulates the activity of the motors. These observations, together with
our theoretical analysis, provide evidence that dynein activity can be
regulated by curvature or normal forces, which may, therefore, play a role in
coordinating the beating of cilia and flagella
The Lewis Strain Gauge Laboratory: Status and plans
An in-house lab was established for developing, testing, and evaluating high-temperature strain gauges and to aid in in-house applications of high-temperature strain instrumentation. The lab is automated to provide computer control of oven temperatures, imposed strain, and data sampling
- …