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Two fault tolerant toggle-hook release

A coupling device is disclosed which is mechanically two fault tolerant for release. The device comprises a fastener plate and fastener body, each of which is attachable to a different one of a pair of structures to be joined. The fastener plate and body are coupled by an elongate toggle mounted at one end in a socket on the fastener plate for universal pivotal movement thereon. The other end of the toggle is received in an opening in the fastener body and adapted for limited pivotal movement therein. The toggle is adapted to be restrained by three latch hooks arranged in symmetrical equiangular spacing about the axis of the toggle, each hook being mounted on the fastener body for pivotal movement between an unlatching non-contact position with respect to the toggle and a latching position in engagement with a latching surface of the toggle. The device includes releasable lock means for locking each latch hook in its latching position whereby the toggle couples the fastener plate to the fastener body and means for releasing the lock means to unlock each said latch hook from the latch position whereby the unlocking of at least one of the latch hooks from its latching position results in the decoupling of the fastener plate from the fastener body

Aberration Corrected Emittance Exchange

Full exploitation of emittance exchange (EEX) requires aberration-free performance of a complex imaging system including active radio-frequency (RF) elements which can add temporal distortions. We investigate the performance of an EEX line where the exchange occurs between two dimensions with normalized emittances which differ by multiple orders of magnitude. The transverse emittance is exchanged into the longitudinal dimension using a double dog-leg emittance exchange setup with a five cell RF deflector cavity. Aberration correction is performed on the four most dominant aberrations. These include temporal aberrations that are corrected with higher order magnetic optical elements located where longitudinal and transverse emittance are coupled. We demonstrate aberration-free performance of an EEX line with emittances differing by four orders of magnitude, \textit{i.e.} an initial transverse emittance of 1~pm-rad is exchanged with a longitudinal emittance of 10~nm-rad

Nano-modulated electron beams via electron diffraction and emittance exchange for coherent x-ray generation

We present a new method for generation of relativistic electron beams with current modulation on the nanometer scale and below. The current modulation is produced by diffracting relativistic electrons in single crystal Si, accelerating the diffracted beam and imaging the crystal structure, then transferring the image into the temporal dimension via emittance exchange. The modulation period can be tuned by adjusting electron optics after diffraction. This tunable longitudinal modulation can have a period as short as a few angstroms, enabling production of coherent hard x-rays from a source based on inverse Compton scattering with total accelerator length of approximately ten meters. Electron beam simulations from cathode emission through diffraction, acceleration and image formation with variable magnification are presented along with estimates of the coherent x-ray output properties

Differences in Shade Tolerance Help Explain Varying Success of Two Sympatric Alnus Species

Alnus maritima and Alnus serrulata are riparian shrubs that occur in similar habitats in the southern and eastern United States.Alnus serrulata is abundant throughout this range, but A. maritima is rare, occurring only in small populations in Oklahoma and Georgia and on the Delmarva Peninsula. Alnus maritima is more resistant than A. serrulata to water and temperature stresses, but the degree to which insolation influences the restricted distribution of A. maritima is unknown. Our goals were to characterize the shade tolerance of A. maritima and A. serrulata and determine whether differences in shade tolerance could help explain the differing ecological success of the two species. Measurements in nature showed that leaves of A. serrulatahave greater concentrations of chlorophyll than do leaves of A. maritima, and a greater percentage of A. serrulata inhabit shaded sites. Two experiments evaluating the resistance of seedlings to light‐deficit stress revealed that A. maritima had a greater photosynthetic capacity and grew more quickly than A. serrulata in full sunlight. In shade, survival of seedlings was lower and reductions in photosynthesis and growth were greater for A. maritima than for A. serrulata. We conclude that A. serrulata is tolerant and A. maritima is intolerant of shade. Moreover, we conclude that shade intolerance strongly restricts the potential niches of A. maritima within the region where the shade‐tolerant A. serrulata is comparatively abundant

Geology of Hood Spring quadrangle, Brewster County, Texas

Accompanied by 3 fold-outs. Plate I : Geologic map and structure sections of Hood Spring quadrangle, Texas. Plate VII : Geologic map and structure sections of Maravillas Creek area, Hood Spring quadrangle, Texas. Plate VIII : Geologic map and structure sections of Tinaja Range area, Hood Spring quadrangle, TexasUT Librarie

High Root-Zone Temperatures Inhibit Growth and Development of Fraga ria Species 1•

The influence of root-zone temperature on strawberry species has not been thoroughly studied. Two experiments were conducted to determine the effect of root-zone temperature on vegetative growth, runner number, runner plant development, and water relations in Fragaria chiloensis Duch., F. virginiana Ouch., and F. viridis Ouch. In Experiment I, clones of F. chiloensis \u27FRA 366\u27 that originated in California, F. chilaensis \u27FRA 606\u27 (Alaska), F. virginiana \u27FRA 67\u27 (Maryland), and F. virginiana \u27FRA 104\u27 (Wyoming) were grown hydroponically for 21 days with root zones at 23, 29, or 35°C. All clones with roots held at 35°C had less fresh mass gain over time, fewer runners, fewer runner plants, less leaf area on mother and runner plants, and less root dry mass than plants at 23 or 29°C. Plants at 29°C had less runner plant leaf area than plants at 23°C. F virginiana exhibited greater vegetative growth and produced more runners and runner plants than F. chiloensis, but there were no species-temferature interactions. In Experiment II, F. chiloensis \u27FRA 366\u27 (mother plants originating in California and F. viridis \u27FRA 333\u27 (Germany) were grown hydroponically for 56 aays with root zones at 23, 29, 35, 20/26 (night!dax). 26/32 , or 32!38°C. F. viridis was more sensitive to high root-zone temperature than F chiloensis, and most growth reductions were associated with reduced transpiration and leaf water potential. A low temperature (23°C) promoted maximum growth of F. viridis, whereas exposure to root-zone temperatures as high as 32°C fostered maximum growtli of F. chiloensis

Conodonts from the Marathon basin, Brewster County, Texas

Conodonts were discovered in the limestones of the Marathon region in the Big Bend country, Brewster County, Texas, as a result of field work during the summer of 1939. This was not the first known occurrence of these fossils from this region, however, as King earlier mentioned the occurrence of conodonts in siliceous shales of Devonian age. The discovery of conodonts in the Ordovician and Pennsylvanian limestones of the area had its inception in the attempt to determine whether the Dimple limestone (lower Pennsylvanian) or Maravillas limestone (upper Ordovician) was involved in a fault that was being mapped. These limestones are similar lithologically and the nature of the outcrop along the fault trace was such that the age relations of the limestone involved could not be determined...The stratigraphic distribution, systematic descriptions, and illustrations of conodonts of Ordovician and Pennsylvanian age from the Marathon region form the basis of this thesis. In some instances, such as the occurrence in the dimple formation, conodonts are the only positively identifiable fossils found in the rocks and, for this reason, have special significance in determining the age of these beds. The Ordovician conodont faunas are of importance because the occurrence in this region extends their known geographic and geologic range --Introduction, pages [1]-3