A straw tube chamber is a low-cost version of a proportional counter. These devices consist of a pair of coaxial conducting cylinders with the region between the cylinders filled with a gas such as argon. The inner cylinder of radius a is the anode, and is held at potential V ; the outer cylinder of radius b is the cathode, and is grounded. If a penetrating charged particle passes through the c...

Using flawless components are important for a proper material selection and best working conditions to achieve the best performance of solid oxide fuel cells (SOFCs). Tape casting is the most used process for the fabrication of SOFC parts, especially anode and electrolyte due to its advantages regarding the other processes. In this study, the effect of slurry composition and milling time were s...

In this paper, we investigate the optimization of tensile strain caused by thermal oxidation in a doubly-clamped silicon nanowire FET to enhance the mobility of its carriers. Spacer technology combined with sacrificial oxidations was used to fabricate ≈ 100 nm wide nanowires. The temperature and the duration of sacrificial wet oxidation are the main parameters that determine the induced strain....

A novel Silicon Sacrificial Layer Dry Etching (SSLDE) technique using sputtered amorphous or LPCVD polycrystalline silicon as sacrificial layers and a dry fluorine-based (SF6) plasma chemistry as releasing process is reported with a detailed experimental study of the release etching step. The process is capable of various applications in surface micromachining process, and can be applied in fab...

A hypothesis of the beam auto–focusing in the relativistic vacuum diode with a needle anode is proposed. A physical model of the effect is elaborated. As is shown, auto –focusing of high current beam can be caused by ions emitting from the anode. Initial (pre focusing) stage of focusing is provided with ionization of the gas molecules absorbed in the anode surface. Then (at quasi–steady stage),...

The fabrication of SiC MEMS pressure sensor based on novel vacuum-sealed method is presented in this paper. The sensor was fabricated using surface micromachining. Due to its excellent mechanical properties and high chemical resistance, PECVD (Plasma Enhanced Chemical Vapor Deposition) SiC was chosen as structural material. Polyimide is the sacrificial layer which solve stiction problem in proc...

however, the conventional gold recovery process is cyanidation, due to the recent environmental laws; researchers are looking for alternative methods for the recovery of gold. furthermore, the copper anode slime is one of the most important secondary sources of gold (about 1200 ppm). so, the main objective of the current work is gold separation from copper anode slime as a rich secondary source...

We investigate the entropic force-elongation behavior of a polymer chain in the presence of the sacrificial bond and hidden length (SBHL) system observed experimentally in many biomaterials. We show that in most cases the SBHL system leads to a significant increase in toughness. However, the presence of a large number of bonds or relatively strong bonds in the SBHL system can reduce the net gai...

Cycling tests under various conditions have been performed for lithium ion battery anodes made from free-standing silicon microwires embedded at one end in a copper current collector. Optimum charging/discharging conditions have been found for which the anode shows negligible fading (< 0.001%) over 80 cycles; an outstanding result for this kind of anodes. Several performance parameters of the a...

In this study, a whole-cell 3D multiphase non-isothermal model is developed for hydrogen alkaline anion exchange membrane (AAEM) fuel cell, and the interfacial effect on the two-phase transport in porous electrode is also considered in the model. The results show that the insertion of anode MPL, slight anode pressurization and reduction of membrane thickness generally improve the cell performan...