Design, fabrication, and testing of microelectromechanical system spark gap switch based on streamer theory

In order to realize that the fuze micro system has both high security and miniaturization characteristics, the spark gap research of Micro-Electro-Mechanical System safety system is carried out. So that to solve the safe and reliable function of the spark gap switch under the low power supply voltage (35 V) of the fuze micro system, the gas gap size and electrode radius are shown to significantly affect the gas breakdown voltage using streamer theory. Based on these results, a spark gap switch with triggering electrodes is designed. The triggering electrode gap is 2 μm and the main electrode gap is 10 μm. A spark gap switch test circuit is designed based on the RLC circuit. Through finite element simulation, it is verified that the gas breakdown voltage increases nonlinearly with increasing gap size. Pre-breakdown spark gap switches were fabricated based on the surface silicon process and tested. The test results show that the conduction voltage values of the triggering electrode and the main electrode are basically consistent with the simulation and calculation results. The breakdown voltage of the main electrode can be greatly reduced by applying a certain voltage to the triggering electrode, realize the reliable function in the micro fuze system.

The Surge of Metal–Organic-Framework (MOFs)-Based Electrodes as Key Elements in Electrochemically Driven Processes for the Environment

Metal–organic-frameworks (MOFs) are emerging materials used in the environmental electrochemistry community for Faradaic and non-Faradaic water remediation technologies. It has been concluded that MOF-based materials show improvement in performance compared to traditional (non-)faradaic materials. In particular, this review outlines MOF synthesis and their application in the fields of electron- and photoelectron-Fenton degradation reactions, photoelectrocatalytic degradations, and capacitive deionization physical separations. This work overviews the main electrode materials used for the different environmental remediation processes, discusses the main performance enhancements achieved via the utilization of MOFs compared to traditional materials, and provides perspective and insights for the further development of the utilization of MOF-derived materials in electrified water treatment.

Comparative Study on Electrochemical Treatment of Cyanide Wastewater

The electrochemical treatment of wastewater is widely used for cleaning due to its efficiency. In this paper, two-dimensional (2D) and three-dimensional (3D) electrochemical systems were used to treat cyanide wastewater. The effect of the applied voltage and the material of the main electrode on the removal of various ions and the characteristics of chemical reactions were mainly studied. The results show that the applied voltage was the key effect of the electrochemical treatment process. The removal of ions from the wastewater at 2 V is mainly due to the effect of electro adsorption and enrichment precipitation, while at 4 V, it is mainly due to anodization and cathodic deposition. The treatment effect of the 3D electrode system was significantly better than the 2D system. The 3D electrode system by used granular activated carbon as the particle electrode, with the carbon filled stainless mesh (CM) and coal based electrode (CB) as the main electrode, the treatment effect were better than main electrode of stainless steel mesh (M). The 3D system with CB as the main electrode had an applied voltage of 4 V, a treatment time of 5 h, plate spacing of 10 mm, and the dosage of activated carbon particles was 2 g. The removal rates of CNT, Cu, Zn, CN−, and SCN− were 94.14, 94.53, 98.14, 98.55, and 93.13%, respectively. The main reaction in anode was the electroly oxidation of CN− and SCN−, while the electrolytic deposition of Cu, Zn, and other metal ions in the cathode surface. There were not only adsorption and electric adsorption of various ions, but also an electrolytic deposition reaction of Cu, Zn, and other metal ions on the surface of the activated carbon particle electrode. During the electrochemical reaction, the concentration of hydrogen ions near the anode increases locally, which produces the precipitation of CuSCN, Cu2Fe(CN)6, and Zn2Fe(CN)6, etc. in the solution, which are helpful for the removal of cyanide and heavy metal ions in cyanide wastewater.

Densities and electrochemical potential window of the BaCl2-NaCl-NaF-AlF3 electrolyte

The effect of melt composition (BaCl2-NaCl-NaF-AlF3) on its density, resistivity and redox potentials of the main electrode processes is reported. A three-factor two-level experimental design was used to study the effects of cryolite ratio (1.1-1.6) and BaCl2 (0-60wt%) or NaCl (0-10wt%) content on the melt density. The obtained equation satisfactorily describes the measured melt densities. The observed non-linear behavior of melt density with BaCl2 additions is assigned to the formation of BaClF complex. Unlike BaCl2, additions of 0-10 wt% NaCl have little effect on the melt density, however, affect the melt conductivity significantly.

Review of Microelectrode Fabrication

With the development of electrode technology and deepening research on bio-medical discovery, various micro-neuron probes have been designed and manufactured. Electrodes, a carrier of stimulating and recording neuron signals consists of the main part of probe. In the last ten years, as the micro-manufacturing technology constantly develops and creates, the electrode structure has been integrated onto a new level. The article will give a compound conclusion on the manufacture methods of the main electrode types in the course of development.

Vitrification Technology Development Plan in Tokai Reprocessing Plant

The Tokai Vitrification Facility (TVF) is the only operating vitrification plant in Japan, constructed and operated by JAEA, to vitrify concentrated high radioactive liquid waste (HALW) in the Tokai Reprocessing Plant (TRP). JAEA started TVF hot operation in 1995 and produced 218 canisters as of March, 2006. An existing melter is the second melter, which was installed from 2002 to 2004 in place of the first melter stopped its operation by damage of a main electrode. JAEA has estimated that the damage was caused by accumulation of noble metal. Therefore, melter bottom structure was improved to get better drain ability of glass containing noble metal. Completing the melter replacement, vitrification operation was restarted in October 2004 and produced 88 canisters successfully until the end of March 2006. Through these experiences, JAEA made basic strategy to achieve stable TVF operation: keeping stable operation of the existing melter preventing adverse effect by noble metal accumulation and developing a new advanced melter with long lifetime preparing for future exchange as the third melter. Based on the basic strategy, JAEA made a decade development plan of necessary key technologies and has started the development since 2005.