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Full-Text Articles in Engineering
Potential High Resolution Dosimeters For Mrt, E. Brauer-Krisch, Anatoly B. Rosenfeld, Michael L. Lerch, Marco Petasecca, M. Akselrod, J. Sykora, J. Bartz, M. Ptaszkiewicz, P. Olko, A. Berg, M. Wieland, S. Doran, T. Brochard, A. Kamlowski, G. Cellere, A. Paccagnella, Erik A. Siegbahn, Y. Prezado, I. Martinez-Rovira, A. Bravin, Laurent Dusseau, P. Berkvens
Potential High Resolution Dosimeters For Mrt, E. Brauer-Krisch, Anatoly B. Rosenfeld, Michael L. Lerch, Marco Petasecca, M. Akselrod, J. Sykora, J. Bartz, M. Ptaszkiewicz, P. Olko, A. Berg, M. Wieland, S. Doran, T. Brochard, A. Kamlowski, G. Cellere, A. Paccagnella, Erik A. Siegbahn, Y. Prezado, I. Martinez-Rovira, A. Bravin, Laurent Dusseau, P. Berkvens
Faculty of Engineering - Papers (Archive)
Microbeam Radiation Therapy (MRT) uses highly collimated, quasi-parallel arrays of X-ray microbeams of 50-600 keV, produced by 2nd and 3rd generation synchrotron sources, such as the National Synchrotron Light Source (NSLS) in the U.S., and the European Synchrotron Radiation Facility (ESRF) in France, respectively. High dose rates are necessary to deliver therapeutic doses in microscopic volumes, to avoid spreading of the microbeams by cardiosynchronous movement of the tissues. A small beam divergence and a filtered white beam spectrum in the energy range between 30 and 250 keV results in the advantage of steep dose gradients with a sharper penumbra than …
High-Energy, Picosecond, Cryogenic Yb:Yag Chirped-Pulse Amplifier At Khz Repetition Rates For Opcpa Pumping, Kyung-Han Hong, Juliet Gopinath, Darren Rand, Aleem M. Siddiqui, Shu-Wei Huang, Enbang Li, Benjamin J. Eggleton, John D. Hybl, Tso Yee Fan, Franz X. Kartner
High-Energy, Picosecond, Cryogenic Yb:Yag Chirped-Pulse Amplifier At Khz Repetition Rates For Opcpa Pumping, Kyung-Han Hong, Juliet Gopinath, Darren Rand, Aleem M. Siddiqui, Shu-Wei Huang, Enbang Li, Benjamin J. Eggleton, John D. Hybl, Tso Yee Fan, Franz X. Kartner
Faculty of Engineering and Information Sciences - Papers: Part A
We report on the development of a 50-mJ-class ~10-ps chirped-pulse amplifier at kHz repetition rates using cryogenic Yb:YAG regenerative and multi-pass amplifiers. The system is well suited as pump laser for kHz high-average-power ultra-broadband OPCPAs. '2010 Optical Society of America
High-Energy, Khz-Repetition-Rate, Ps Cryogenic Yb:Yag Chirped-Pulse Amplifier, Kyung-Han Hong, Juliet Gopinath, Darren Rand, Aleem M. Siddiqui, Shu-Wei Huang, Enbang Li, Benjamin J. Eggleton, John D. Hybl, Tso Yee Fan, Franz X. Kartner
High-Energy, Khz-Repetition-Rate, Ps Cryogenic Yb:Yag Chirped-Pulse Amplifier, Kyung-Han Hong, Juliet Gopinath, Darren Rand, Aleem M. Siddiqui, Shu-Wei Huang, Enbang Li, Benjamin J. Eggleton, John D. Hybl, Tso Yee Fan, Franz X. Kartner
Faculty of Engineering and Information Sciences - Papers: Part A
We demonstrate amplification of picosecond laser pulses to 40 mJ at a 2 kHz pulse repetition frequency (PRF) from a two-stage cryogenic chirped-pulse Yb:YAG amplifier, composed of a regenerative amplifier (RGA) and a two-pass booster amplifier. The RGA produces 8.2 mJ of energy at 2 kHz PRF and 13.2 mJ at 1 kHz PRF with excellent energy stability (~0.3% rms) and beam quality ( M2<1.1 ). Pulse stretching and compression are achieved by using a chirped fiber Bragg grating and a multilayer dielectric grating pair, respectively. Compressed 15 ps pulses from the RGA are obtained with a throughput efficiency of ~80% (~6.5 mJ for 2 kHz ). The booster amplifier further amplifies the pulses to 40 mJ at 2 kHz PRF, and ~32 mJ, ~15 ps pulses are expected after compression. The amplifier chain seeded from a femtosecond Yb-fiber laser enables the optical self-synchronization between signal and pump in optical parametric chirped-pulse amplifier applications.
Investigation Of High Resolution Compact Gamma Camera Module Based On A Continuous Scintillation Crystal Using A Novel Charge Division Readout Method, Qiu-Sheng Dai, Cui-Lan Zhao, Hualin Zhang, Yujin Qi
Investigation Of High Resolution Compact Gamma Camera Module Based On A Continuous Scintillation Crystal Using A Novel Charge Division Readout Method, Qiu-Sheng Dai, Cui-Lan Zhao, Hualin Zhang, Yujin Qi
Faculty of Engineering and Information Sciences - Papers: Part A
The objective of this study is to investigate a high performance and lower cost compact gamma camera module for a multi-head small animal SPECT system. A compact camera module was developed using a thin Lutetium Oxyorthosilicate (LSO) scintillation crystal slice coupled to a Hamamatsu H8500 position sensitive photomultiplier tube (PSPMT). A two-stage charge division readout board based on a novel sub-tractive resistive readout with a truncated center-of-gravity (TCOG) positioning method was developed for the camera. The performance of the camera was evaluated using a flood 99mTc source with a four-quadrant bar-mask phantom. The preliminary experimental results show that the image …
Evaluation Of High Temperature Fatigue Behaviour Of P22 By Miniature Specimen Testing, M D. Callaghan, S. R Humphries, M Law, H Li, W.Y Yeung
Evaluation Of High Temperature Fatigue Behaviour Of P22 By Miniature Specimen Testing, M D. Callaghan, S. R Humphries, M Law, H Li, W.Y Yeung
Faculty of Engineering - Papers (Archive)
Miniature specimen testing to evaluate mechanical properties, presents a novel opportunity to undertake structural integrity assessments of in-service power generation components, by removing only a very small volume of material. In this study, high temperature fatigue testing of P22 steel was undertaken and a number of fatigue properties determined using a miniature specimen testing methodology. Good comparisons were observed between fatigue properties determined by miniature specimens and the more established standard-sized specimen testing reported in literature.
A Study Of The Continous Cooling Behaviour And Effect Of Preheat And Interpass Temperature On The Haz Of High Strength Quenched And Tempered Steel, Lenka Kuzmikova, Mark Callaghan, Nathan Larkin, Robert Scott, Robert De Jong, Huijun Li, John Norrish
A Study Of The Continous Cooling Behaviour And Effect Of Preheat And Interpass Temperature On The Haz Of High Strength Quenched And Tempered Steel, Lenka Kuzmikova, Mark Callaghan, Nathan Larkin, Robert Scott, Robert De Jong, Huijun Li, John Norrish
Faculty of Engineering - Papers (Archive)
In this study, the continuous cooling phase transformation behaviour of a quenched and tempered armour steel was investigated. A continuous cooling transformation diagram was constructed providing valuable information for predicting microstructural evolution and mechanical properties at different cooling rates during actual welding fabrication. Welding trials were carried out utilising flux-cored arc welding technique in combination with an austenitic stainless steel consumable. The effect of various preheat and interpass temperatures on cooling rate and consequently on the heat affected zone microstructure and mechanical properties of multipass welds were investigated.
High-Surface-Area -Fe2o3/Carbon Nanocomposite: One-Step Synthesis And Its Highly Reversible And Enhanced High-Rate Lithium Storage Properties, S X. Dou, David Wexler, Jiazhao Wang, Hua-Kun Liu, Konstantin K. Konstantinov, Chao Zhong, Shulei Chou
High-Surface-Area -Fe2o3/Carbon Nanocomposite: One-Step Synthesis And Its Highly Reversible And Enhanced High-Rate Lithium Storage Properties, S X. Dou, David Wexler, Jiazhao Wang, Hua-Kun Liu, Konstantin K. Konstantinov, Chao Zhong, Shulei Chou
Faculty of Engineering - Papers (Archive)
Hollow-structured α-Fe2O3/carbon (HIOC) nanocomposite with a high surface area of around 260 m2 g−1 was synthesized by a one-step, in situ, and industrially-oriented spray pyrolysis method using iron lactate and sucrose solution as the precursors. The small α-Fe2O3 nanocrystals were highly dispersed inside amorphous carbon to form a carbon nanocomposite. Electrochemical measurements showed that the carbon played an important role in affecting both the cycle life and the rate capability of the electrode. The HIOC composites showed the best electrochemical performance in terms of high capacity (1210 mAh g−1 …
Anisotrophic Currents And Flux Jumps In High-Tc Superconducting Films With Self-Organized Arrays Of Planar Defects, V Yurchenko, A.J Qviller, P.B Mozhaeva, J.E Mozhaeva, J.B Hansen, C Jacobsen, I.M Kotelyanskii, Alexey V. Pan, T H. Johansen
Anisotrophic Currents And Flux Jumps In High-Tc Superconducting Films With Self-Organized Arrays Of Planar Defects, V Yurchenko, A.J Qviller, P.B Mozhaeva, J.E Mozhaeva, J.B Hansen, C Jacobsen, I.M Kotelyanskii, Alexey V. Pan, T H. Johansen
Faculty of Engineering - Papers (Archive)
Regular arrays of planar defects with a period of a few nanometers can be introduced in superconducting YBa2Cu3O7-δ (YBCO) thin films by depositing them on vicinal (also called miscut or tilted) substrates. This results in the anisotropy of critical currents flowing in the plane of the film. We present results of real-time magneto-optical imaging (MOI) of magnetic flux distribution and dynamics in a series of YBCO thin films deposited on NdGaO3 substrates with different miscut angles θ. MOI allows reconstructing the current flow profiles. From the angle formed between domains with different …
Sno2-Nio-C Nanocomposite As A High Capacity Anode Material For Lithium-Ion Batteries, Mohd Faiz Hassan, Md Mokhlesur Rahman, Zaiping Guo, Zhixin Chen, Hua-Kun Liu
Sno2-Nio-C Nanocomposite As A High Capacity Anode Material For Lithium-Ion Batteries, Mohd Faiz Hassan, Md Mokhlesur Rahman, Zaiping Guo, Zhixin Chen, Hua-Kun Liu
Faculty of Engineering - Papers (Archive)
Carbon-coated SnO2–NiO nanocomposite was successfully synthesized via the molten salt route, using SnCl2·H2O and NiCl2·6H2O as the starting materials, with a molten salt composition of H2O2:LiOH·H2O:LiNO3 as a solvent at 300 °C. The synthesis was followed by a carbon layering process. The phases and morphology of the as-prepared samples were examined by X-ray diffraction and transmission electron microscopy. Electrochemical investigation was carried out by using a series of complementary techniques, including galvanostatic charge–discharge, cyclic voltammetry, and impedance spectroscopy. The results confirmed that the …
High-Strength Ultrafine-Grained Ti-Fe-Sn Alloys With A Bimodal Structure, Lei C. Zhang, H B. Lu, M Calin, E V. Pereloma, J Eckert
High-Strength Ultrafine-Grained Ti-Fe-Sn Alloys With A Bimodal Structure, Lei C. Zhang, H B. Lu, M Calin, E V. Pereloma, J Eckert
Faculty of Engineering - Papers (Archive)
The microstructure-mechanical properties relationship in ultrafine-grained Ti-Fe-Sn alloys with high strength and large plasticity was investigated. The alloys are mainly composed of a hypereutectic microstructure with micrometer-sized primary dendrites embedded in an ultrafine-grained eutectic matrix. The bimodal composites exhibit a fracture strength higher than 2350 MPa and an enhanced plasticity larger than 7%. The excellent mechanical properties are critically related to the microstructure features of the phase constituents in the alloys.
Direct Scattered Growth Of Mwnt On Si For High Performance Anode Material In Li-Ion Batteries, Pengfei Gao, Yanna Nuli, Yu-Shi He, Andrew I. Minett, Jiazhao Wang, Jun Yang, Jun Chen
Direct Scattered Growth Of Mwnt On Si For High Performance Anode Material In Li-Ion Batteries, Pengfei Gao, Yanna Nuli, Yu-Shi He, Andrew I. Minett, Jiazhao Wang, Jun Yang, Jun Chen
Faculty of Engineering - Papers (Archive)
A novel Si-MWNT nanocomposite synthesized via a CVD process shows a high reversible capacity of over 1500 mAh g−1 and stable cycling performance, which can be ascribed to the maintenance of a good conductive network by means of the direct scattered growth and pinning of MWNTs on Si particles.
Development Of A Family Of High Strength Low Carbon Microalloyed Ultra-Thin Cast Strip Products Produced By The Castrip® Process, Chris R. Killmore, Kristin R. Carpenter, Harold R. Kaul, James G. Williams, Daniel G. Edelman, Peter C. Campbell, Walter N. Blejde
Development Of A Family Of High Strength Low Carbon Microalloyed Ultra-Thin Cast Strip Products Produced By The Castrip® Process, Chris R. Killmore, Kristin R. Carpenter, Harold R. Kaul, James G. Williams, Daniel G. Edelman, Peter C. Campbell, Walter N. Blejde
Faculty of Engineering and Information Sciences - Papers: Part B
The manufacture of high strength strip products in strip thicknesses less than 1.5mm is very challenging for the conventional hot and cold rolled processing routes. A range of Nb and Nb/V microalloyed steels have been successfully strip cast by the CASTRIP process enabling the development of a range of high strength Ultra-Thin Cast Strip (UCS) products. It was found that the CASTRIP process fully exploits the strengthening potential of the low C-Mn-Nb-(V) alloy design system. Substantial strengthening by microstructural hardening was provided by Nb. Retention of Nb and V in solid solution in hot rolled coils enabled further strengthening by …
"Organic" Mgb2-Xcx Superconductor With High Performance Enabled By Liquid Mixing Approach, Olga V. Shcherbakova, Alexey V. Pan, Emil Babic, S. X. Dou
"Organic" Mgb2-Xcx Superconductor With High Performance Enabled By Liquid Mixing Approach, Olga V. Shcherbakova, Alexey V. Pan, Emil Babic, S. X. Dou
Faculty of Engineering - Papers (Archive)
Comparative analysis of structural and electromagnetic characteristics have been performed on nano SiC- and polycarbosilane-doped MgB2 samples prepared by the dry and liquid mixing approaches. The total benefit of liquid mixing approach for fabrication of "organic" MgB2 superconductor with excellent electromagnetic performance has been demonstrated