Band Gap Formation and Tunability in Stretchable Serpentine Interconnects

Serpentine interconnects are highly stretchable and frequently used in flexible electronic systems. In this work, we show that the undulating geometry of the serpentine interconnects will generate phononic band gaps to manipulate elastic wave propagation. The interesting effect of `bands-sticking-together' is observed. We further illustrate that the band structures of the serpentine interconnects can be tuned by applying pre-stretch deformation. The discovery offers a way to design stretchable and tunable phononic crystals by using metallic interconnects instead of the conventional design with soft rubbers and unfavorable damping.Comment: 12 pages, 8 figure

Postglacial colonization and parallel evolution of metal tolerance in the polyploid Cerastium alpinum

The Fennoscandian flora is characterized by a high frequency of polyploids, probably because they were more successful than diploid plants in colonizing after the last Ice Age. The first postglacial colonizers were likely poor competitors and became displaced from the lowlands as forests advanced. Consequently, many of these pioneers are currently found only above tree line. However, some have persisted within the forests on open habitats such as naturally toxic serpentine soils where succession is arrested at the pioneer stage. These populations represent relicts of former widely distributed plants. The polyploid Cerastium alpinum L. (Caryophyllaceae) grows on serpentine soils throughout Fennoscandia. C. alpinum populations on different soil types provide a model system for the study of the early postglacial colonization history of Fennoscandia. Genetic markers showed that C. alpinum populations in western Fennoscandia differ genetically from eastern populations, suggesting a two-way colonization. The two lineages meet in a hybrid zone in Northern Scandinavia where a high degree of genetic variation was found. Plants from Fennoscandia and the Western Arctic (Canada, Greenland and Iceland) shared many AFLP fragments, which suggests they originate from common refugia. The Fennoscandian populations were more distantly related to the populations in potential refugia in southern Europe. In fact, the northern populations contained AFLP fragments not found in populations in the Pyrenees and the Alps. Lack of chloroplast DNA variation indicates fast postglacial range expansions and/or a recent origin of C. alpinum. Crosses were made to establish the inheritance of enzyme markers. The results strengthen the evidence for an allopolyploid origin of C. alpinum. Adjacent serpentine and non-serpentine populations of C. alpinum provide a model system of natural replicates to test whether adaptation to serpentine is constitutive (common for all populations) or locally evolved. A growth experiment with high concentrations of nickel and magnesium, two metals that limit the fertility of serpentine soils, showed that the degree of metal tolerance reflects site-specific soil conditions. Since local adaptation was found in both the eastern and the western immigration lineages, the postglacial colonization of Fennoscandia has involved parallel evolution of metal tolerance in C. alpinum

Serpentuator Patent

Internal and external serpentine devices for performing physical operations around orbital space station

The petrology of fine-grained micrometeorites: Evidence for the diversity of primitive asteroids

We report the discovery by analytical TEM of serpentine and phases interpreted as dehydroxylates of serpentine in ultramicrotomed sections of a number of fine-grained Antarctic micrometeorites

The Dale Oil Field, Caldwell County, Texas

Geological Science

Biogeochemical studies on some nickel accumulating plants from New Zealand and New Caledonian serpentine areas : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Chemistry at Massey University

Serpentine areas in New Zealand and New Caledonia are described. A study was made of soil factors controlling the distribution of five species from a serpentine flora in the Dun Mountain area, South Island, New Zealand. Samples of soil were taken from sites of each of the species, and each sample was analysed for calcium, chromium, cobalt, copper, magnesium, manganese, nickel, potassium and zinc. On the basis of the species growing on them, the soil samples were divided into five groups: group 1, Pimelea suteri; group 2, Myosotis monroi; group 3, Lebe odora; group 4, Cassinia vauvilliersii; group 5, Leptospermum scoparium. Discriminant analysis was used to characterise each group of soils on the basis of chemical composition. The results showed that the two endemic plants (P. suteri and M. monroi) were much more commonly found in localities of highest magnesium concentration. These two species were strongly differentiated by the potassium and copper levels in their soils. No strong elemental discrimination was found among the non-endemic species. Correlation coefficients were calculated for the relationships between pairs of elements and highly-significant correlations (P 0.001) are reported. A nickel accumulating species from New Caledonia, Homalium kanaliense is compared with the New Zealand nickel accumulator, Pimelea suteri. The very high accumulation of nickel in the New Caledonian species, presents interesting questions in plant physiology. Purification of nickel complexes from an aqueous extract of B. kanaliense leaves was achieved and preliminary identification methods employed. None of the nickel was associated with amino acids and the present evidence suggested possible complexing of the nickel to simple carboxyllic sugars

Scanning superconducting quantum interference device on a tip for magnetic imaging of nanoscale phenomena

We describe a new type of scanning probe microscope based on a superconducting quantum interference device (SQUID) that resides on the apex of a sharp tip. The SQUID-on-tip is glued to a quartz tuning fork which allows scanning at a tip-sample separation of a few nm. The magnetic flux sensitivity of the SQUID is 1.8 {\mu}_0/Hz^{1/2} and the spatial resolution is about 200 nm, which can be further improved. This combination of high sensitivity, spatial resolution, bandwidth, and the very close proximity to the sample provides a powerful tool for study of dynamic magnetic phenomena on the nanoscale. The potential of the SQUID-on-tip microscope is demonstrated by imaging of the vortex lattice and of the local AC magnetic response in superconductors.Comment: 10 figure

Design, fabrication, and testing of silicon microgimbals for super-compact rigid disk drives

This paper documents results related to design optimization, fabrication process refinement, and micron-level static/dynamic testing of silicon micromachined microgimbals that have applications in super-compact computer disk drives as well as many other engineering applications of microstructures and microactuators requiring significant out-of-plane motions. The objective of the optimization effort is to increase the in-plane to out-of-plane stiffness ratio in order to maximize compliance and servo bandwidth and to increase the displacement to strain ratio to maximize the shock resistance of the microgimbals, while that of the process modification effort is to simplify in order to reduce manufacturing cost. The testing effort is to characterize both the static and dynamic performance using precision instrumentation in order to compare various prototype designs