نتایج جستجو برای: tantalum compounds

تعداد نتایج: 229110  

2001
George J. Simandl

Recent interest in tantalum is due to increases in spot prices for tantalum raw materials which during 2000 reached US$145 to 175/lb of contained Ta2O5 (Platt’s Metals Week) and as much as US$ 350 /lb which was the bid rate for the Oct 2000 Davis Langdon Australia (DLA) Tender. As a result, exploration companies targeted a variety of pegmatites, specialty granites, alkaline complexes and carbon...

2013
Hongbin Yu Suiyi Zhu Xia Yang Xinhong Wang Hongwei Sun Mingxin Huo

We report a simple method to fabricate nano-porous tantalum oxide films via anodization with Ta foils as the anode at room temperature. A mixture of ethylene glycol, phosphoric acid, NH4F and H2O was used as the electrolyte where the nano-porous tantalum oxide could be synthesized by anodizing a tantalum foil for 1 h at 20 V in a two-electrode configuration. The as-prepared porous film exhibite...

2017
Raymond A. Foos H. A. Wilhelm

The use of liquid-liquid extraction for the separation of tantalum from niobium was demonstrated. Tantalum and niobium spectrographically free of each other were prepared in quantity on a continuous basis.

2013
Iu. N. Maliutina V. I. Mali I. A. Bataev A. A. Bataev M. A. Esikov A. I. Smirnov K. A. Skorokhod

The structure and microhardness of Cu-Ta joints produced by explosive welding were studied. It was found that, during explosive welding, an intermediate layer 20⋯40  μ m thick with a finely dispersed heterophase structure, formed between the welded copper and tantalum plates. The structure of the layer was studied by scanning and transmission electron microscopy. Microvolumes with tantalum part...

2003
Kurt S. Rothenberger Bret H. Howard Richard P. Killmeyer Anthony V. Cugini Robert M. Enick Felipe Bustamante Michael V. Ciocco Bryan D. Morreale Robert E. Buxbaum

The hydrogen permeability of bulk tantalum and tantalum coated with thin films of palladium was measured at temperatures from 623 to 1173 K and hydrogen partial pressures from 0.1 to 2.6 MPa in a flowing gas system. Palladium coatings were deposited by both electroless plating (1–2 m thick Pd layer) and cold plasma-discharge sputtering with two different thicknesses, 0.04 or 1.2 m. All samples ...

2005

Solid-electrolyte tantalum capacitors were first developed and commercially produced in the 1950s. They represented a quantum leap forward in miniaturization and reliability over existing wound-foil wet electrolytic capacitors. While the solid tantalum capacitor has dramatically improved electrical performance versus wet-electrolyte capacitors, especially at low temperatures, today’s electronic...

Journal: :Nature communications 2016
Wei Yi Sergey E Savel'ev Gilberto Medeiros-Ribeiro Feng Miao M-X Zhang J Joshua Yang Alexander M Bratkovsky R Stanley Williams

Tantalum oxide memristors can switch continuously from a low-conductance semiconducting to a high-conductance metallic state. At the boundary between these two regimes are quantized conductance states, which indicate the formation of a point contact within the oxide characterized by multistable conductance fluctuations and enlarged electronic noise. Here, we observe diverse conductance-dependen...

Journal: :Nanoscale 2016
Alexey S Cherevan Spencer Robbins Dennis Dieterle Paul Gebhardt Ulrich Wiesner Dominik Eder

In this work we synthesized well-ordered, Ta2O5 films with a 3D-interconnected gyroid mesopore architecture with large pore sizes beyond 30 nm and extended crystalline domains through self-assembly of tailor-made triblock-terpolymers. This has effectively eliminated diffusion limitations inherent to previously reported mesoporous photocatalysts and resulted in superior hydrogen evolution with a...

2015
Christos G. Paganias George A. Tsakotos Stephanos D. Koutsostathis George A. Macheras

Porous tantalum is a biomaterial that was recently introduced in orthopaedics in order to overcome problems of the past related to implant loosening. Its use has led to very good results, especially in difficult cases where severe bone defect is present, as it is found to have osteoconductive and possibly, osteoinductive properties. So, it is of great interest to shed light to the mechanisms th...

Journal: :Izvestiya Vuzov. Poroshkovaya Metallurgiya i Funktsional’nye Pokrytiya (Proceedings of Higher Schools. Powder Metallurgy аnd Functional Coatings) 2015

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید