Electric Field in Terms of Charge Density
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Mixed Protonic-Electronic Conductors for Hydrogen Separation Membranes
MIXED PROTONIC-ELECTRONIC CONDUCTORS FOR HYDROGEN SEPARATION MEMBRANES By SUN-JU SONG A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY UNIVERSITY OF FLORIDA 2003 To my parents in heaven. ACKNOWLEDGMENTS I would like to thank my advisor, Prof. Eric D. Wachsman, for his guidance, support, and encouragement while I have trodden the path of learning under his tutelage. I will always remember this valuable and rewarding graduate school experience over the years that I have worked with him. I am grateful to Dr. U. Balachandran for his support and careful instruction. I would also like to thank Dr. D. Butt, Dr. W. Sigmund, Dr. D. Norton, and Dr. M. Orazem for kindly participating as part of my dissertation committee. I would like to acknowledge my group members for helping a friend in need, Keith, Suman, Jamie, Jun-young, Matt, Guoging, Abishek, Ruchita, Briggs, Neil, and Eric. Special thanks are given to Keith for helpful discussions and to Jamie for helping with hydrogen permeation measurements. They all are greatly appreciated. I wish them all the best of luck in their endeavors. I would like to thank my three sisters, one brother, and their families from the bottom of my heart. I am sure that they know how deeply I value them. I would also like to thank my wife’s parents for welcoming me into their family, entrusting their precious daughter to me. I acknowledge my beautiful wife, Haemin, who is my support from the moment I wake up until the time I go to bed. -
Electrostatic Separation of Carbon Dioxide by Ionization in Bifurcation Flow
Ito et al., Aerosol and Air Quality Research, Vol. 4, No. 1, pp. 91-104, 2004 Electrostatic Separation of Carbon Dioxide by Ionization in Bifurcation Flow Takao Ito∗, Yoshio Otani and Norikazu Namiki Graduate School of Natural Science & Technology, Kanazawa University, 2-40-20 Kodatsuno, Kanazawa 920-8667, Japan. Abstract Carbon dioxide is one of the major green house gases as well as impurities in process gases used for various manufacturing industries. In the present work, our recently developed ionization separator (Ito et al., Ind. & Eng. Chem. Res., 42, 5617-5621, 2003) was applied to the separation of carbon dioxide from inert gases. As a result, it was found that carbon dioxide can be separated mostly in the form of anion although some fraction of carbon dioxide decomposes by the soft X-ray irradiation. The maximum efficiency of electrostatic separation of carbon dioxide was 14% when helium stream contains 2.4 ppm of carbon dioxide at the applied voltage of 600V and the separation efficiency was decreased with increase in the inlet concentration. The dependency of separation efficiency on the applied voltage was qualitatively explained by the separation model that accounted for the electrical migration, the generation and the neutralization of anions and cations formed from carbon dioxide. Keywords: ionization, soft X-ray, electrical migration, carbon dioxide, separation. 1. Introduction Reduction of carbon dioxide (CO2) concentration in air and other gases has been of great concern in various fields; e.g., control of indoor air quality by ventilation (Nabinger et al., 1994, Persily, 1997), green house effect (Hansen et al., 1981), contamination control of process gases for semiconductor manufacturing (Briesacher et al., 1991). -
Twenty Three-Twenty Seven Weeks Material Structure
Twenty three-twenty seven weeks Material structure To understand the fundamental concepts of semiconductors, one must know material structure. There are two type of the material according to the doping with impurities or not. Material doped with material (donor) that has negative charge called N- type and material doped with material (acceptor) that has positive charge called P- type. It could change from intrinsic to extrinsic and vise verse by introduction impurity, temperature, light and magnetic field Some term in material structure Order: it is concept that used to distinguish the regularity or other atomic packing. Phase: a volume of the material which contain no discontinuity in either composition or structure. Grain: a single crystal in polycrystalline aggregate. Crystal: a substance that has definite solidified geometrical form. Amorphous: non-crystalline has no definite form or shape Single crystal: a monolithic material grown and has a regular molecules pattern in repetitive 3- D. Polycrystalline: a monolithic material contain more than one crystal oriented in random and separated by boundaries. factors specify the crystal structure are 1- Geometric framework 2- Atom arrangement 3- Distribution in that framework Typical semiconductor Two properties of crystals are of particular interest, since they are needed to calculate the current in a semiconductor. First, we need to know how many fixed and mobile charges are present in the material. Second, we need to understand the transport of the mobile carriers through the semiconductor Semiconductors and Insulators have totally full valence bands and empty conduction bands with a band gap between them. When carriers transfer valence band to conduction band that lead to conduct the material. -
Pdf 1011.2 K
Journal of Chemical Reviews, 2020, Volume 2, Issue 3, Pages 182-188 Short Review Article Estimation of the Diffusion Coefficient and Hydrodynamic Radius (Stokes Radius) for Inorganic Ions in Solution Depending on Molar Conductivity as Electro-Analytical Technique-A Review Muhammed J. Kadhim *, Maher Ibraheem Gamaj * Department of Power Mechanical Techniques, Institute of Technology-Baghdad, Middle Technical University, Baghdad, Iraq Receive Date: 18 January 2020, Revise Date: 04 March 2020, Accept Date: 07 April 2020 Abstract: Diffusion coefficient (D) and radiuses of inorganic charge ions (R) in different environments is of importance in scientific fields, explaining certain features of ions. D values were obtained using the Einstein- Smoluchowski equation depending on limiting molar conductivity (λo) of inorganic charge ions. Inorganic ions have D values at the range of 1−3×10−9 m2.s-1, except hydroxyl and hydrogen ion (5.2×10−9 and 9.1×10−9 m2.s-1, respectively). The hydrodynamic radius R for diffusing ions was calculated using the Stokes–Einstein equation based on D values. Inorganic ions have R, values at the range of 1−3×10−10 m, except hydroxyl and hydrogen ion (R=0.47×10−10 and 0.27×10−10 m, respectively). DOI: 10.33945/SAMI/JCR.2020.3.5 Keywords: Diffusion coefficient; Hydrated radius; Molar conductance; Movement of ions Graphical Abstract: Graphical abstract illustration the conductance of ions (A), and the diffusion of ions (B), in solution. Biography: Muhammed J. Kadhim Assistant lecturer obtained B.Sc. in chemistry in 1997 and M.Sc. in 2001 from Chemistry Department, Science College, Baghdad University, Iraq.