Relevant bibliographies by topics / Metal-induced gap states

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  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers

Academic literature on the topic 'Metal-induced gap states'

Author: Grafiati
Published: 4 June 2021
Last updated: 2 February 2022

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Journal articles on the topic "Metal-induced gap states"

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Kiguchi, Manabu, and Koichiro Saiki. "Metal-induced gap states at insulator/metal interfaces." e-Journal of Surface Science and Nanotechnology 2 (2004): 191–99. http://dx.doi.org/10.1380/ejssnt.2004.191.

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Sajjad, Muhammad, Xinbo Yang, Pietro Altermatt, Nirpendra Singh, Udo Schwingenschlögl, and Stefaan De Wolf. "Metal-induced gap states in passivating metal/silicon contacts." Applied Physics Letters 114, no. 7 (February 18, 2019): 071601. http://dx.doi.org/10.1063/1.5066423.

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Kiguchi, Manabu, Genki Yoshikawa, Susumu Ikeda, and Koichiro Saiki. "Metal induced gap states at alkali halide/metal interface." Applied Surface Science 237, no. 1-4 (October 2004): 495–98. http://dx.doi.org/10.1016/j.apsusc.2004.06.127.

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Betti, M. G., G. Bertoni, V. Corradini, V. De Renzi, and C. Mariani. "Metal-induced gap states at InAs(110) surface." Surface Science 454-456 (May 2000): 539–42. http://dx.doi.org/10.1016/s0039-6028(00)00065-0.

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Railkar, T. A., and S. V. Bhoraskar. "Detection of metal induced gap states in silicon." Applied Physics Letters 66, no. 8 (February 20, 1995): 974–75. http://dx.doi.org/10.1063/1.113816.

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Kiguchi, M., G. Yoshikawa, K. Saiki, R. Arita, and H. Aoki. "Metal induced gap states at tetratetracontane/Cu interface." Journal de Physique IV (Proceedings) 132 (March 2006): 199–203. http://dx.doi.org/10.1051/jp4:2006132038.

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Oncel, N., W. J. van Beek, B. Poelsema, and H. J. W. Zandvliet. "Metal induced gap states on Pt-modified Ge(001) surfaces." New Journal of Physics 9, no. 12 (December 20, 2007): 449. http://dx.doi.org/10.1088/1367-2630/9/12/449.

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Stiles, K., A. Kahn, D. Kilday, and G. Margaritondo. "Metal‐induced gap states at the Ag and Au/GaAs interfaces." Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films 6, no. 3 (May 1988): 1511–14. http://dx.doi.org/10.1116/1.575351.

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Gao, Zhengning, Mallik M. R. Hussain, Domenico de Ceglia, Maria A. Vincenti, Andrew Sarangan, Imad Agha, Michael Scalora, Joseph W. Haus, and Parag Banerjee. "Unraveling delocalized electrons in metal induced gap states from second harmonics." Applied Physics Letters 111, no. 16 (October 16, 2017): 161601. http://dx.doi.org/10.1063/1.4996893.

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Fung, M. K., S. L. Lai, S. W. Tong, S. N. Bao, C. S. Lee, and S. T. Lee. "Interface gap states of 8-hydroxyquinoline aluminum induced by cesium metal." Chemical Physics Letters 392, no. 1-3 (July 2004): 40–43. http://dx.doi.org/10.1016/j.cplett.2004.05.047.

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Dissertations / Theses on the topic "Metal-induced gap states"

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Hohenecker, Stefan. "Chalcogen modification of GaAs(100) surfaces and metal/GaAs(100) contacts." Doctoral thesis, Universitätsbibliothek Chemnitz, 2002. http://nbn-resolving.de/urn:nbn:de:swb:ch1-200200268.

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Der Einfluss der Modifikation der technologisch relevanten GaAs(100) Oberfläche durch Chalkogene, i.e. Selen, Schwefel und Tellur, wird in dieser Arbeit untersucht. Es wird ein Modell vorgestellt, das die Eigenschaften der modifizierten Oberfläche beschreibt. In einem zweiten Schritt werden die so modifizierten Oberflächen mit Metallen unterschiedlicher Reaktivität und verschiedenen Elektronegativitäten bedampft. Die Bandbreite dieser Eigenschaften wird durch die Metalle Indium und Silber, das Alkalimetall Natrium, das Erdalkalimetall Magnesium und das Halbmetall Antimon abgebildet. Die Untersuchung des Einflusses der Chalkogene auf die chemischen Eigenschaften und die Barrierenhöhe der Metall/GaAs(100) Grenzfläche bilden einen weiteren Schwerpunkt. Die Änderung der Barrierenhöhe wird dabei mit Hilfe des Modells metallinduzierter Bandlückenzustände (metal induced gap states) erklärt. Als experimentelle Techniken werden Photoemissionsspektroskopie, Raman Spektroskopie und Strom-Spannungsmessungen verwendet
The influence of a modification of the technological relevant GaAs(100) surface by chalcogens, i.e. selenium, sulphur and tellurium, is evaluated in this work. A model is proposed, which describes the properties of the modified surface. In a second step metals of different reactivity and electronegativity have been evaporated onto these modified surfaces. Among these materials were the metals indium and silver, the alkali metal sodium, the earth alkali metal magnesium and the half metal antimony. The investigation of the influence of chalcogens on the chemical properties and the barrier height of the metal/GaAs(100) interface is another point of interest. The change in barrier height is explained by the model of metal induced gap states (MIGS). Photoemission spectroscopy, Raman spectroscopy and current-voltage-measurement have been used as experimental techniques
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Hohenecker, Stefan. "Chalcogen modification of GaAs(100) surfaces and metal/GaAs(100) contacts." Doctoral thesis, ISBN 3-8265-9907-1, 2001. https://monarch.qucosa.de/id/qucosa%3A17805.

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Der Einfluss der Modifikation der technologisch relevanten GaAs(100) Oberfläche durch Chalkogene, i.e. Selen, Schwefel und Tellur, wird in dieser Arbeit untersucht. Es wird ein Modell vorgestellt, das die Eigenschaften der modifizierten Oberfläche beschreibt. In einem zweiten Schritt werden die so modifizierten Oberflächen mit Metallen unterschiedlicher Reaktivität und verschiedenen Elektronegativitäten bedampft. Die Bandbreite dieser Eigenschaften wird durch die Metalle Indium und Silber, das Alkalimetall Natrium, das Erdalkalimetall Magnesium und das Halbmetall Antimon abgebildet. Die Untersuchung des Einflusses der Chalkogene auf die chemischen Eigenschaften und die Barrierenhöhe der Metall/GaAs(100) Grenzfläche bilden einen weiteren Schwerpunkt. Die Änderung der Barrierenhöhe wird dabei mit Hilfe des Modells metallinduzierter Bandlückenzustände (metal induced gap states) erklärt. Als experimentelle Techniken werden Photoemissionsspektroskopie, Raman Spektroskopie und Strom-Spannungsmessungen verwendet.
The influence of a modification of the technological relevant GaAs(100) surface by chalcogens, i.e. selenium, sulphur and tellurium, is evaluated in this work. A model is proposed, which describes the properties of the modified surface. In a second step metals of different reactivity and electronegativity have been evaporated onto these modified surfaces. Among these materials were the metals indium and silver, the alkali metal sodium, the earth alkali metal magnesium and the half metal antimony. The investigation of the influence of chalcogens on the chemical properties and the barrier height of the metal/GaAs(100) interface is another point of interest. The change in barrier height is explained by the model of metal induced gap states (MIGS). Photoemission spectroscopy, Raman spectroscopy and current-voltage-measurement have been used as experimental techniques.
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Iffländer, Tim. "Electronic and Magnetic Properties of the Fe/GaAs(110) Interface." Doctoral thesis, 2015. http://hdl.handle.net/11858/00-1735-0000-0028-86DE-A.

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Books on the topic "Metal-induced gap states"

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Nitta, J. Spin generation and manipulation based on spin-orbit interaction in semiconductors. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198787075.003.0013.

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This chapter focuses on the electron spin degree of freedom in semiconductor spintronics. In particular, the electrostatic control of the spin degree of freedom is an advantageous technology over metal-based spintronics. Spin–orbit interaction (SOI), which gives rise to an effective magnetic field. The essence of SOI is that the moving electrons in an electric field feel an effective magnetic field even without any external magnetic field. Rashba spin–orbit interaction is important since the strength is controlled by the gate voltage on top of the semiconductor’s two-dimensional electron gas. By utilizing the effective magnetic field induced by the SOI, spin generation and manipulation are possible by electrostatic ways. The origin of spin-orbit interactions in semiconductors and the electrical generation and manipulation of spins by electrical means are discussed. Long spin coherence is achieved by special spin helix state where both strengths of Rashba and Dresselhaus SOI are equal.
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Book chapters on the topic "Metal-induced gap states"

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Kahn, A., K. Stiles, D. Mao, S. F. Horng, K. Young, J. McKinley, D. G. Kilday, and G. Margaritondo. "Metal-GaAs(110) Interfaces Formed at Low Temperature: From Adsorbate- to Metal-Induced Gap States." In NATO ASI Series, 163–78. Boston, MA: Springer US, 1989. http://dx.doi.org/10.1007/978-1-4613-0795-2_10.

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Tiwari, Sandip. "Semiconductor interfaces and junctions." In Semiconductor Physics, 228–47. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780198759867.003.0006.

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This chapter discusses understanding interfaces, how bulk state reasoning needs to evolve under the constraints of the surface and how these changes relate to interfaces. Interfaces and junctions connect semiconductors to the world and introduce perturbations of their own. Starting with a discussion of the SiO­­­2-Si interface—an amorphous-crystalline interface—with its local evolution, more general conditions—of metals, insulators and semiconductors—with defect states, induced gap states and Fermi pinning are discussed. Next, neutrality level as a defining idea for the establishment of the electronic behavior of metal-semiconductor and semiconductor-semiconductor interfaces is examined. Crystalline continuity leading to heterostructures with conduction band and valence band discontinuities are developed and related to bulk bandstructure. This allows one to analytically describe and show the junction band diagrams of abrupt and graded junctions. Nitride systems often have a polarized junction, that is, have large polarization—spontaneous and often piezoelectric—whose origin is explored.
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Conference papers on the topic "Metal-induced gap states"

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Nakaoka, T., K. Shiraishi, Y. Akasaka, T. Chikyow, K. Yamada, and Y. Nara. "First-principles studies on metal induced gap states (MIGS) at metal/high-k HfO2 interfaces." In 2005 International Conference on Solid State Devices and Materials. The Japan Society of Applied Physics, 2005. http://dx.doi.org/10.7567/ssdm.2005.a-9-3.

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Nishimura, T., T. Yajima, and A. Toriumi. "Control of Fermi Level Pinning at Metal/Ge Interface Based on a Reconsideration of Metal-induced Gap States Model." In 2016 International Conference on Solid State Devices and Materials. The Japan Society of Applied Physics, 2016. http://dx.doi.org/10.7567/ssdm.2016.o-6-02.

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Hussain, Mallik M. R., Zhengning Gao, Domenico de Ceglia, Maria A. Vincenti, Andrew Sarangan, Imad Agha, Michael Scalora, Parag Banerjee, and Joseph W. Haus. "A Second Harmonic Technique to Determine Metal-Induced-Gap-State Density." In Frontiers in Optics. Washington, D.C.: OSA, 2017. http://dx.doi.org/10.1364/fio.2017.jtu3a.93.

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Kammerer, Matthias C., Xaver Schuler, Stefan Weihe, Michael Seidenfuß, Mi Zhou, Eckart Laurien, and Rudi Kulenovic. "Thermo-Mechanical Loading of Full-Scale Welded Piping Components in High Temperature Water Environment." In ASME 2017 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/pvp2017-65606.

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The effect of high-temperature water environment on the fatigue life of steels used for pressure retaining components has been discussed controversially for the last 20 to 30 years. Fatigue testing of laboratory specimens for typical steels showed significant drops in fatigue life when tested in high temperature water environment compared to air environment. Based on these findings the applicability of fatigue design curves such as those enclosed to ASME code Section III NB are questionable concerning their degree of conservatism. Nevertheless, experience from components experiencing power plant operation does not match up with laboratory fatigue testing of small uniaxial specimens. Fatigue life estimations based on models representing laboratory tests do highly overestimate the fatigue life reduction resulting from high temperature water environments compared to the analyses of components having reached their postulated fatigue life. To overcome this disagreement component testing under defined laboratory conditions is highly desired to achieve “gap closure”. At MPA University of Stuttgart a test facility was set up where environmental fatigue testing on component level can be realized within a hot water test loop. Within the framework of a research project sponsored by the German Federal Ministry of Education and Research (BMBF) piping modules containing a dissimilar metal weld are exposed to water environments with alternating temperature conditions. At specific locations water at about room temperature is injected to a hot pipe segment which results in thermal induced loading situations. Consequently thermal stratification and shocks cause localized stresses and strains in the tested modules. Within this paper an overview of the testing procedure, the tested materials and results from both experimental measurements and fractographic analyses are presented and discussed. In addition to experimental investigations the results drawn from a coupled computational fluid dynamics (CFD) and structural mechanics finite-element-analysis (FEA) including a fatigue life assessment are shown. Finally, this work states on the applicability of common fatigue assessment procedures including the fatigue life reducing factors based on the results from realistic fatigue testing on component level. Within low cycle fatigue tests a nickel-base weld material was characterized regarding its fatigue life in air and high temperature water environment in comparison. It was found that the effect of environmentally assisted fatigue is in good agreement with what is known from literature for smooth specimens made from austenitic steels. Results from tests using notched specimens showed a significant change in the environmental effect compared to tests using smooth specimens. During component testing within a hot water loop modules which contain a dissimilar metal weld were exposed to alternating water temperature conditions between 20 °C and 65 °C. At the end of the component test cracks were found in the regions where the highest temperature changes were measured and calculated. The numerical analysis of the fluid-structure-interaction pointed out that the transition region between the austenitic steel and the nickel base weld material is the highest loaded section within the module. Finally the fatigue assessment of the pipe sections containing cracks showed that based on common fatigue hypothesis the loading state is regarded to be subcritical.
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Moore, Karen A., Robert Carrington, John Richardson, and Ray A. Zatorski. "Application of Data Transmission Capability on Natural Gas Transmission Pipelines." In 2002 4th International Pipeline Conference. ASMEDC, 2002. http://dx.doi.org/10.1115/ipc2002-27074.

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Third party damage is as a significant factor in natural gas pipeline failures. 75% of pipeline failures induced by a third party occur immediately following impact. Current inspection techniques are both labor intensive and expensive to implement and they represent only a point in time status. The objective is for a near real time detection and communication system that utilizes the pipe itself, i.e., a “smart pipe”. The industry is calling for an inexpensive rugged process that transmits the state of the pipe. The INEEL is developing a near real time damage detection and location system that utilizes resistive traces applied to the wall of the pipe, which detects damage by measuring the strain state of the pipeline. This data will also allow for efficient repairs and emergency response. The technique employed is a network of thermally sprayed resistive traces deposited on either the interior or exterior wall of the pipeline. The ability of a thermally sprayed resistive trace to detect damage is due to the unique manner in which a porous metal changes resistivity when placed under strain.
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Honjo, Yoshio, Masahiro Furuya, Tomoji Takamasa, and Koji Okamoto. "Interfacial Phenomena of Radiation-Induced and Photo-Induced." In 16th International Conference on Nuclear Engineering. ASMEDC, 2008. http://dx.doi.org/10.1115/icone16-48320.

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When a metal oxide is irradiated by gamma rays, the irradiated surface becomes hydrophilic. This surface phenomenon is called as radiation induced surface activation (RISA). In order to investigate radiation-induced and photo-induced hydrophilicity, the contact angles of water droplets on a titanium dioxide surface were measured in terms of irradiation intensity and time for gamma rays of cobalt-60 and for ultraviolet rays. Reciprocals of the contact angles increased in proportion to irradiation time before the contact angles reached their super-hydrophilicity state. The reciprocals of contact angles correlate well with integrated intensity by a straight line, regardless of the irradiation intensity and time. Radiation-induced and photo-induced hydrophilicity phenomena are identical to each other in this regard. In addition, an effect of ambient gas was investigated. In pure argon gas, the contact angle remains the same against the irradiation time. This clearly shows that a certain humidity in ambient gas is required to take the place of RISA hydrophilicity. A single crystal titanium dioxide (100) surface was analyzed by X-ray photoelectron spectrometry (XPS). After irradiation with gamma rays, a peak was found in the O 1s spectrum, indicating the adsorption of dissociative water to a surface 5-fold coordinate titanium site, and the formation of a surface hydroxyl group. We conclude that the RISA hydrophilicity is caused by chemisorption of the hydroxyl group on the surface.
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Pierce, James V., and Lawrence F. Shuniak. "Reduced Device Life Caused by Flux Entrapment During the Construction Process." In ISTFA 1998. ASM International, 1998. http://dx.doi.org/10.31399/asm.cp.istfa1998p0347.

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Abstract Devices that are sealed with a process using flux (all solder seals, some brazed seals some weld seals, etc.) will have residual flux entrapped. Devices with an internal construction such that areas exist where solvents can not completely clean surfaces exposed to flux vapor will also have residual flux entrapped. This entrapped flux will cause these devices to be susceptible to electromigration induced failure prior to the normal end-of-life of the device. If solder flux is trapped within a device, elevated temperature operation will shorten the life of the device. At elevated temperature, the activators in the flux will become a vapor and act as a catalyst for electromigration. Metal will be distributed across the surface between the "anode" and the "cathode" of the applied potential. The metal will be pulled from the "anode" to the "cathode". The electromigration can be stopped (or slowed) by reducing the maximum temperature the device will be exposed to when a potential is applied. If the amount of entrapped flux is not sufficient to bridge the gap between the "anode" and the "cathode" of the potential when in a non-vapor state (liquid or solid), the electromigration will be stopped when the temperature is below that needed for the flux activators to be in a vapor state. This paper contains details of this failure mode in hermetically sealed EMI filters and includes life test data (insulation resistance at elevated temperature), life reduction calculations, and photographs of the electromigration.
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Zhuang, Chuanjing. "Safety Requirements for the Second High-Pressure and Large-Diameter West-East Gas Pipeline." In ASME 2007 Pressure Vessels and Piping Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/pvp2007-26823.

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The Second West-East Gas Pipeline (WEGP) is planed be constructed trans-China within recent years. The Pipeline is about 7,000 kilometers with outside diameter 1219mm, operation pressure 12MPa, and steel grade API-X80 [1], all of which is the first time in China. Both safety and reliability of the Pipeline are the most important issues which should be thought over by the gas company. In this paper, the method of limit state analysis is used to study the effect of strength, toughness and allowable flaw size on the safety and reliability of the Pipeline. The calculation results suggest that the overmatched weld has the advantages of improving limit load and maximum allowable defect sizes of the pipelines. When Ms (Ms is the ratio of yield strength of weld σSW over that of base metal σSB, i.e. MS = σSW / σSB) is lower than 0.9, there is much possibility for the happening of fracture initiation in the weld zone. When Ms is higher than 1.2, the limit load will not increase with the increase of weld strength. Although the Second WEGP will transmit sweet gas, there is still possibility that sour gas releases to the Pipeline in case of operation accident. As to the high-grade pipeline, in order to reduce the sensitivity of cold crack, hydrogen induced crack (HIC) and stress induced corrosion crack (SCC), etc., However, chemical composition and hardness of both base and weld metal can influence the resistance to HIC and SCC. It can be concluded that the best range of strength mismatched ratios Ms is 0.9 ∼ 1.2 for the Second WEGP. The critical defect sizes proposal is 10.0mm of maximum allowable defect length and 0.95mm of maximum allowable defect depth at the weld mismatch.
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El-Jummah, Abubakar M., Gordon E. Andrews, and John E. J. Staggs. "Conjugate Heat Transfer CFD Predictions of Impingement Jet Array Flat Wall Cooling Aerodynamics With Single Sided Flow Exit." In ASME Turbo Expo 2013: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/gt2013-95343.

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Conjugate heat transfer CFD studies were undertaken on impingement square jet arrays with self induced crossflow in the impingement gap with a single sided exit. The aim was to understand the aerodynamic interactions that result in the deterioration of heat transfer with axial distance, whereas the addition of duct flow heat transfer would be expected to lead to an increase in heat transfer with axial distance. A square array of impingement holes was investigated for a common geometry investigated experimentally, pitch to diameter ratio X/D of 5 and impingement gap to diameter ratio Z/D of 3.3 for 11 rows of holes in the crossflow direction. A metal duct wall was used as the impingement surface with an applied heat flux of 100kW/m2, which for a gas turbine combustor cooling application operating at steady state with a temperature difference of ∼450K corresponds to a convective heat transfer coefficient of ∼200 W/m2K. A key feature of the predicted aerodynamics was recirculation in the plane of the impingement jets normal to the cross-flow, which produced heating of the impingement jet wall. This reverse flow jet was deflected by the cross flow which had its peak velocity in the plane between the high velocity impingement jets. The cross-flow interaction with the impingement jets reduced the interaction between the jets on the surface, with lower surface turbulence as a result and this reduced the surface convective heat transfer. A significant feature of the predictions was the interaction of the cross-flow aerodynamics with the impingement jet wall and associated heat transfer to that wall. The results showed that the deterioration in heat transfer with axial distance was well predicted, together with predictions of the impingement wall surface temperature gradients.
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Yang, Shanglu, Wei Huang, Dechao Lin, Fanrong Kong, and Radovan Kovacevic. "Monitoring of the Spatter Formation in Laser Welding of Galvanized Steels in Lap Joint Configuration by the Measurement of the Acoustic Emission." In ASME 2008 International Manufacturing Science and Engineering Conference collocated with the 3rd JSME/ASME International Conference on Materials and Processing. ASMEDC, 2008. http://dx.doi.org/10.1115/msec_icmp2008-72224.

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Galvanized steels have been widely used in the different industries such as automotive, aerospace and marine industry, due to their high corrosion resistance and excellent mechanical properties. However, the zinc coating on the metal sheet offers a big challenge to the welding operation, specifically in the high-power laser welding process of the lap joint if the metal sheets are installed in a gap-free configuration. Spatters, one of the critical problems for the weld quality, is readily generated by the high-pressurized zinc vapor developed at the interface of two metal sheets. It takes extra procedures to clean the weld surface or repair the blowholes generated by the spatters. The on-line process monitoring is critical to assure the achievement of the high quality welds. Therefore, it is necessary to develop an on-line efficient monitoring system for the welding of galvanized steels. In the past few years, acoustic emission (AE) technique has been applied to monitor different manufacturing processes. This paper will highlight its application in the laser welding of galvanized steels. An AE signal acquisition system is used to real-time monitor the welding process. The results of the investigation show that the amplitude of AE signals varies with the welding process status. When the welding process is stable, the amplitudes of AE signals are almost constant and with the low intensity compared to the AE emission signals when the weld defects are presented. When the spatter is formed, a sharp spike with the high amplitude is shown in the collected acoustic emission signal. In order to extract the features of the AE signals in frequency domain, the acquired signal in time domain is further processed using Short-time Fourier Transformation (STFT). The STFT processed results indicated that the spatter-induced AE signals cover a wide range of frequencies and the background noise is mainly presented in the range below 100 Hz.
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