Search results for "Plating"
showing 10 items of 65 documents
Delamination and recycling of Archaean crust caused by gravitational instabilities
2013
The volume of Archaean crust preserved at Earth’s surface today is low. Thermodynamic calculations and geodynamic modelling show that the thick, primary crust that would have formed on a much hotter Archaean Earth was denser than the underlying mantle, and would have therefore been recycled back into the mantle as drips.
SHRIMP ZIRCON AGES AND PETROLOGY OF LOWER CRUSTAL GRANULITE XENOLITHS FROM THE LETSENG-LA-TERAE KIMBERLITE, LESOTHO: FURTHER EVIDENCE FOR A NAMAQUA-N…
2013
Recrystallized zircons extracted from intermediate granulites of the Letseng-la-Terae Diamond Mine in northeastern Lesotho provide evidence that the Tugela Terrane of the Mesoproterozoic high-grade Namaqua-Natal mobile belt may extend ~200 km farther west than previously thought. The rock-forming minerals in the investigated lower crustal granulites contain garnet, clinopyroxene, plagioclase and quartz or garnet, wollastonite, plagioclase and quartz. Calculated values for peak granulite-facies metamorphism are ~13 kbar and ~850°C. Thermal overprint and therein granulite-facies metamorphism occurred during the late Mesoproterozoic and is documented by SHRIMP metamorphic zircon ages of 1018 ±…
Tethyan vs. Cordilleran ophiolites: a reappraisal of distintctive tectono-magmatic features of supra-subduction complexes in relation to the subducti…
2004
Abstract Supra-subduction zone (SSZ) ophiolites deserve special attention because they represent fundamental markers of intraoceanic convergence and generation of new lithosphere above subduction zones. Moreover, owing to their structural characteristics and location in the overriding plate, these complexes are far better represented and preserved than Mid-Ocean-Ridge-Basalt (MORB) ophiolites in orogenic belts. In terms of their structure, tectonics, and magmatic features, SSZ ophiolites may be classified in two main types: (1) “Tethyan complexes” (such as those of the Albanide-Hellenide belt), which mostly consist of complete and extensive volcanic, dyke, plutonic, and mantle sections with…
Reworking of the Tarim Craton by underplating of mantle plume-derived magmas: Evidence from Neoproterozoic granitoids in the Kuluketage area, NW China
2011
Abstract Most Neoproterozoic granitoids in the Kuluketage area, northern Tarim Craton are characterized by strongly depleted HREE abundances and high Sr/Y and (La/Yb) N ratios, showing typical geochemical features of adakitic rocks. Zircon U–Pb dating of three adakitic plutons yielded Neoproterozoic ages (754 ± 4, 790 ± 3 and 798 ± 3 Ma). The adakitic granitoids exhibit low MgO and TiO 2 contents. Their low Cr, Co and Ni abundances, low ɛ Hf ( t ) values (−21 to −11) and high FeO T /MgO ratios (mostly 2.2–2.9) preclude the possibility of being derived from partial melts of delaminated lower crust. The relatively low ɛ Hf ( t ) values and old Hf two-stage model ages ( T DM 2 = 2 . 42 – 3 .0 …
Electroplated Indium Bumps as Thermal and Electrical Connections of NTD-Ge Sensors for the Fabrication of Microcalorimeter Arrays
2012
We are developing a method to build arrays of Ge-based microcalorimeters for soft X-rays detection using micro-photolithographic techniques. A key element of the process is the electrical and thermal connection between the germanium sensors and the interconnection electrical tracks, that lay on a substrate acting as mechanical support and thermal sink. The geometry of the sensors, that have a square base truncated pyramid shape, makes feasible a connection through indium soldering. We describe a technique, based on microlithography and electroplating, adopted to grow indium bumps of a few tens of square microns of area and several microns high on top of the contact pads patterned on the sub…
Fabrication of Single Cylindrical Au-Coated Nanopores with Non-Homogeneous Fixed Charge Distribution Exhibiting High Current Rectifications
2014
We have designed and characterized a cylindrical nanopore that exhibits high electrochemical current rectification ratios at low and intermediate electrolyte concentrations. For this purpose, the track-etched single cylindrical nanopore in polymer membrane is coated with a gold (Au) layer via electroless plating technique. Then, a non-homogeneous fixed charge distribution inside the Au-coated nanopore is obtained by incorporating thiol-terminated uncharged poly(N-isopropylacrylamide) (PNIPAM) chains in series to poly(4-vinyl pyridine) (PVP) chains, which are positively charged at acidic pH values. The functionalization reaction is checked by measuring the current–voltage (I–V) curves prior …
Spermidine and morphogenesis in single cell cultures of Sideritis angustifolia lag.
1990
Abstract Single cells from hypocotyl-derived callus of Sideritis angustifolia were evaluated for morphogenesis when cultured in either solidifier or liquid Murashige and Skoog medium supplemented with various concentrations of spermidine, naphthaeneacetic acid (NAA), benzyladenine (BA) and dicyclohexylamine (DCHA). Spermidine (Spd) did not replace the hormonal requirements for cell division and callus formation, but affected growth induced by NAA or BA. This polyamine increased the plating efficiency of cells cultured in the presence of NAA (0.05, 0.54 and 5.40 μM) or BA (0.40, 4.40 and 8.80 μM). In contrast, Spd reduced growth induced by 10.80 μM NAA, optimal auxin concentration for callus…
Morphogenesis in callus and single-cell cultures ofLavandula latifoliaMedicus
1990
Procedures and factors promoting plant regeneration from callus and isolated cells were investigated in Lavandula latifolia Medicus. Callus was obtained from cotyledon explants cultured on MS medium supplemented with 0.34 (xM 2,4-D. These calli regenerated adventitious buds when transferred to MS medium containing either BA or several auxin (IAA or NAA)/BA combinations, best results being obtained in the presence of 8.80 (mi BA alone or in combination with 0.06 and 0.60 (xM IAA or NAA. Single cells from cotyledon-derived calli were able to proliferate as callus when plated in MS medium supplemented with IAA or several IAA/BA combinations. Best plating efficiency was achieved when cells were…
Excess volatiles supplied by mingling of mafic magma at an andesite arc volcano
2010
We present the results of a study of volcanic gases at Soufriere Hills Volcano, Montserrat, which includes the first spectroscopic measurements of the major gas species CO2 and H2S at this volcano using a Multisensor Gas Analyzer System (MultiGAS) sensor. The fluxes of CO2 and H2S were 640.2750 t/d and 84.266 t/d, respectively, during July 2008, during a prolonged eruptive pause. The flux of CO2 is similar to estimates for the entire arc from previous geochemical studies, while the measured H2S flux significantly alters our interpretation of the sulphur budget for this volcano. The fluxes of both sulphur and carbon show considerable excesses over that which can be supplied by degassing of e…
Thermo-mechanical role of a Cambro-Ordovician paleorift during the Variscan collision: the NE margin of the Bohemian Massif
2001
Abstract The Stare Město (SM) belt (NE margin of the Bohemian Massif) represents a preserved example of an intracontinental Cambro-Ordovician rift that has been shortened during the Variscan orogeny. The rifted sequence consists of gabbroic intrusions and a leptyno-amphibolite complex of Cambro-Ordovician protolith age. The latter suffered medium pressure, granulite facies, Cambro-Ordovician metamorphism associated with extension in a continental protorift. The Variscan tectonometamorphic event is manifested by convergent orogenesis with syn-convergent intrusion of a Carboniferous tonalitic sill, high temperature–medium pressure compressional deformation of gabbros and high temperature meta…