Annotated record of the detailed examination of Mn deposits from DSDP Site 25, Leg 4 (Core 4-25A-1)

At the Leg 4 pre-cruise meeting in Miami, Florida, in January 1969, the Ridge site was proposed as an additional site to be investigated, if possible. Since the water depth and sediment thickness at this site were both minimal (2000 meters and less than 100 meters, respectively) and the location was not far from the track between initially planned sites, the shipboard party decided, upon completion of work at Site 24, to make a 24-hour drilling effort on the North Brazilian Ridge. The drilling objectives at this location were to sample and date the sediments atop the Ridge crest and to determine the nature, age and origin of the consolidated material beneath the thin mantle of sediment.

Annotated record of the detailed examination of Mn deposits from DSDP Site 26, Leg 4 (Core 4-26-1)

Site 26 was selected on the crest of the Mid-Atlantic Ridge between 15°N and 5°S is offset to the east nearly 4000 kilometers through a series of fracture zones. One of the most prominent of these is the Vema Fracture Zone, a narrow east-west trending trough which cuts through the Mid-Atlantic Ridge at latitude 11°N.

Annotated record of the detailed examination of Mn deposits from DSDP Site 29, Leg 4 (Hole 4-29B)

The southern Caribbean basins are thought to be part of a relatively old and geologically stable crustal plate. Although surrounded by belts of high earthquake activity, the central Caribbean is seismically quiet. The region also constitutes a quiet magnetic zone and appears to have resisted all of the surrounding forces related to ocean floor spreading. In addition to providing considerable information on the general geologic history of the Caribbean region, paleontologic studies on cores at Site 29 were expected to provide valuable data on phylogenetic trends within the planktonic foraminifera and calcareous nannoplankton, furnishing more accurate criteria for intercontinental stratigraphic correlation. The work reported here is a biostratigraphic summary of available samples. only the most important and biostratigraphically significant components of the faunas have been noted. No attempt has been made to give an exhaustive faunal analysis of the samples seen.

Chemical composition of manganese deposits (Birnessite) from Scotland

A manganese pan near Birness contains grains of an optically uniaxial negative mineral near (Na0.7Ca0.3)Mn7O14·2·8H2O, giving an X-ray powder pattern similar to that of synthetic materials described as 'manganous manganite' and delta-MnO2. Material giving a similar pattern has been described from a natural occurrence in Canada, but no mineral name was assigned; the name birnessite is now proposed. The mineral is probably formed by air-oxidation of manganous oxides under alkaline conditions.

Relations between A-type granites and copper mineralization as exemplified by the Machangqing Cu deposit

This paper deals with the relations between the Machangqing rockbody which corresponds to the A-type granites and porphyry copper mineralization in terms of petrochemistry, trace element geochemistry, fluid inclusion geochemistry and isotope geochemistry. The results show that the Machangqing porphyry copper deposit was formed from the fluid predominated by mag-matic fluid. This kind of ore-forming fluid was just differentiated from the magma responsible for the A-type granites. therefore,as viewed from whereer they contain water or not,the A-type granites can,at least,be divided into two types: water-bearing and water-free.The water-bearing A-type granites can serve as the host ofporphyry copper deposits under certain geological conditions.

Aluminum-assisted crystallization and p-type doping of polycrystalline Si

Aluminum-doped p-type polycrystalline silicon thin films have been synthesized on glass substrates using an aluminum target in a reactive SiH 4+Ar+H2 gas mixture at a low substrate temperature of 300∈°C through inductively coupled plasma-assisted RF magnetron sputtering. In this process, it is possible to simultaneously co-deposit Si-Al in one layer for crystallization of amorphous silicon, in contrast to the conventional techniques where alternating metal and amorphous Si layers are deposited. The effect of aluminum target power on the structural and electrical properties of polycrystalline Si films is analyzed by X-ray diffraction, Raman spectroscopy, scanning electron microscopy and Hall-effect analysis. It is shown that at an aluminum target power of 100 W, the polycrystalline Si film features a high crystalline fraction of 91%, a vertically aligned columnar structure, a sheet resistance of 20.2 kΩ/□ and a hole concentration of 6.3×1018 cm-3. The underlying mechanism for achieving the semiconductor-quality polycrystalline silicon thin films at a low substrate temperature of 300∈°C is proposed.

Low temperature (< 100 °c) deposited P-type cuprous oxide thin films: Importance of controlled oxygen and deposition energy

With the emergence of transparent electronics, there has been considerable advancement in n-type transparent semiconducting oxide (TSO) materials, such as ZnO, InGaZnO, and InSnO. Comparatively, the availability of p-type TSO materials is more scarce and the available materials are less mature. The development of p-type semiconductors is one of the key technologies needed to push transparent electronics and systems to the next frontier, particularly for implementing p-n junctions for solar cells and p-type transistors for complementary logic/circuits applications. Cuprous oxide (Cu2O) is one of the most promising candidates for p-type TSO materials. This paper reports the deposition of Cu2O thin films without substrate heating using a high deposition rate reactive sputtering technique, called high target utilisation sputtering (HiTUS). This technique allows independent control of the remote plasma density and the ion energy, thus providing finer control of the film properties and microstructure as well as reducing film stress. The effect of deposition parameters, including oxygen flow rate, plasma power and target power, on the properties of Cu2O films are reported. It is known from previously published work that the formation of pure Cu2O film is often difficult, due to the more ready formation or co-formation of cupric oxide (CuO). From our investigation, we established two key concurrent criteria needed for attaining Cu2O thin films (as opposed to CuO or mixed phase CuO/Cu2O films). First, the oxygen flow rate must be kept low to avoid over-oxidation of Cu2O to CuO and to ensure a non-oxidised/non-poisoned metallic copper target in the reactive sputtering environment. Secondly, the energy of the sputtered copper species must be kept low as higher reaction energy tends to favour the formation of CuO. The unique design of the HiTUS system enables the provision of a high density of low energy sputtered copper radicals/ions, and when combined with a controlled amount of oxygen, can produce good quality p-type transparent Cu2O films with electrical resistivity ranging from 102 to 104 Ω-cm, hole mobility of 1-10 cm2/V-s, and optical band-gap of 2.0-2.6 eV. These material properties make this low temperature deposited HiTUS Cu 2O film suitable for fabrication of p-type metal oxide thin film transistors. Furthermore, the capability to deposit Cu2O films with low film stress at low temperatures on plastic substrates renders this approach favourable for fabrication of flexible p-n junction solar cells. © 2011 Elsevier B.V. All rights reserved.