مطالعات نظری بر روی ماهیت پیوندهای C→E و E→M در کمپلکس های [NHC→E2H4→M(CO)5] (E=Ge, Sn, Pb, M=Cr, Mo, W)

Seebeck coefficient measurements on Li, Sn, Ta, Mo, and W

The thermopower of W, Mo, Ta, Li and Sn has been measured relative to stainless steel, and the Seebeck coefficient of each of these materials has then been calculated. These are materials that are currently relevant to fusion research and form the backbone for different possibl e liquid limiter concepts includ ing TEMHD concepts such as LiMIT. For molybdenum the Seebeck coefficient has a linear...

W. W. "Mo" Cleland: a catalytic life.

Professor W. Wallace Cleland, the architect of modern steady-state enzyme kinetics, died on March 6, 2013, from injuries sustained in a fall outside of his home. He will be most remembered for giving the enzyme community Ping-Pong kinetics and the invention of dithiothreitol (DTT). He pioneered the utilization of heavy atom isotope effects for the elucidation of the chemical mechanisms of enzym...

Ceria Reduction via Ce-Sn Bimetallic Bonding

Tin was deposited in the amount of 0.4 and 0.8 nm onto CeO2(111) surface by molecular beam deposition at the temperature of 520 K. The interaction of tin with cerium oxide was studied with use of XPS, UPS and RPES (Resonant Photoelectron Spectroscopy). The strong tin – ceria interaction led to the Ce(4-nx)+Snxn+O22compound formation. It was accompanied with partial reduction of CeO2 observed as...

The Kinetics of Formation of Ternary Intermetallic Alloys in Pb-Sn and Cu-Ag-Sn Pb-free Electronic Joints

A simple model of the formation of Au0.1Ni0.1Sn0.8 in Pb-Sn solder/Ni interconnects is examined by numerical simulation. Previous experimental observation has shown that after reflow the interface consists of the Ni3Sn4 alloy between Pb-Sn solder and Ni, with Au distributed through the PbSn solder ball. Au0.1Ni0.1Sn0.8 was observed to form at the Pb-Sn solder/Ni3Sn4 interface during annealing a...

Solder Joint Reliability of Pb-free Sn-Ag-Cu Ball Grid Array (BGA) Components in Sn-Pb Assembly Process

For companies that choose to take the Pb-free exemption under the European Union’s RoHS Directive and continue to manufacture tin-lead (Sn-Pb) electronic products, there is a growing concern about the lack of Sn-Pb ball grid array (BGA) components. Many companies are compelled to use the Pb-free Sn-Ag-Cu (SAC) BGA components in a Sn-Pb process, for which the assembly process and solder joint re...

پارادایم های روش شناسی در مطالعات نظری