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Type Anderson, C. R.; Lee, R. N.
  Publication Accurate measurements of electron energies by field-emitter referencing Volume Journal Article
Pages 1984
  Abstract Journal of Electron Spectroscopy and Related Phenomena  
  Corporate Author J. Electron Spectrosc. Relat. Phenom.  
Publisher 34  
Editor (up) 2
  Summary Language 173-198 Series Editor  
Abbreviated Series Title A new technique of electron Spectroscopy is described in which a standard electron spectrometer is used to compare the electron energy to be measured with the energies of electrons from a field-emitter reference source. Since the reference electrons are emitted at the Fermi level of the emitter tip, their total energy can be accurately measured with a high precision digital voltmeter. The measurements are automatically referenced to the absolute scale of energies and the need for calibration standards is eliminated. The application of the technique to X-ray photoelectron Spectroscopy (XPS) is described. Detailed analysis shows that the uncertainty in the field-emitter referenced XPS measurements is ± 0.06 electron volts.
  Series Issue ISSN  
Medium
  Expedition Notes  
Call Number  
Contribution Id  
Serial URL ISBN  
no 8497
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Kang, M.-J.; Pyun, J.-C.; Lee, J.-C.; Choi, Y.-J.; Park, J.-H.; Park, J.-G.; Lee, J.-G.; Choi, H.-J. Nanowire-assisted laser desorption and ionization mass spectrometry for quantitative analysis of small molecules Journal Article 2005 Rapid Communications in Mass Spectrometry 19 21 3166-3170 1097-0231 no NU @ karnesky @ Kang2005 9529
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Lee, S.-W.; Yeh, J.-W. Superplasticity of 5083 alloys with Zr and Mn additions produced by reciprocating extrusion Journal Article 2007 Materials Science and Engineering: A 460-461 409-419 Aluminum alloys; Extrusion; Superplasticity In this study, 5083 aluminum alloys modified with grain refiner, 0.25% Zr and 0.46% Mn, were processed by reciprocating extrusion to yield high-strain-rate superplasticity above 400 [degree sign]C and superior room-temperature mechanical properties. Without any prior homogenization treatment, 10 extrusion passes could give the cast billets an equiaxed grain structure with a grain size of about 4.5 [mu]m and a subgrain size about 0.2 [mu]m, and a uniform distribution of fine inclusions and dispersoids in the matrix. The fine-grained structure was stable up to 525 [degree sign]C, giving the alloy a high-strain-rate and low-stress superplasticity over a wide operating temperature of 400-500 [degree sign]C. In the tensile test at 500 [degree sign]C, a maximum elongation of 1013% and a low flow stress of 7.7 MPa at 5 x 10-2 s-1 were achieved. The apparent and true activation energies for low temperatures (300-400 [degree sign]C) without high-strain-rate superplasticity were 220.6 and 208 kJ/mol, respectively, whereas those at high temperatures (400-500 [degree sign]C) were 88.4 and 98.7 kJ/mol, respectively. Further analysis confirms that grain boundary sliding is the dominant mechanism over the high-strain-rate region from 1 x 10-2 to 5 x 10-1 s-1 at 500 [degree sign]C, and power-law breakdown mechanism occurs over the strain rate from 5 x 10-4 to 1 x 10-2 s-1 at 300 [degree sign]C. The high-strain-rate superplasticity was more strongly enhanced by Zr addition than addition of Cr and Mn. Two enhancing mechanisms for the maximum superplastic elongation and the optimum strain rate are proposed. This study concludes that the effectiveness of Zr is caused by the fineness and the coherency of Zr-rich dispersoids in the matrix. no NU @ karnesky @ 9637
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Vaynman, S.; Fine, M.E.; Lee, S.; Espinosa, H.D. Effect of strain rate and temperature on mechanical properties and fracture mode of high strength precipitation hardened ferritic steels Journal Article 2006 Scripta Materialia 55 4 351-354 Steel; Fracture; Strain rate effect no NU @ p-kolli @ 9683
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Jiang, C.; Gleeson, B. Effects of Cr on the elastic properties of B2 NiAl: A first-principles study Journal Article 2006 Scripta Materialia 55 9 759-762 Chromium; Nickel aluminides; Point defects; First-principle electron theory We performed first-principles calculations based on the density functional theory to investigate the effects of Cr addition on the elastic properties of B2 NiAl. The Wagner-Schottky model was employed to correlate single-crystal elastic constants of ternary B2 NiAl-Cr alloys with point defect concentrations, in which the defect-formation parameters were obtained from first-principles supercell calculations. The present calculations clearly show that the effects of Cr addition on the elastic properties of B2 NiAl are strongly composition-dependent. no NU @ p-kolli @ 9710
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Jiang, C.; Sordelet, D.J.; Gleeson, B. Effects of Pt on the elastic properties of B2 NiAl: A combined first-principles and experimental study Journal Article 2006 Acta Materialia 54 9 2361-2369 Platinum; Nickel aluminides; Point defects; First-principles electron theory First-principles calculations were performed to investigate the effects of Pt addition on the elastic properties of B2 NiAl. By correlating single-crystal elastic constants with point defect concentrations in the context of the Wagner-Schottky model, a general equation is proposed to calculate elastic properties of ternary B2 NiAl-Pt alloys as a function of alloy composition, in which the defect formation parameters were obtained from first-principles supercell calculations. At constant Al content, the calculations showed that the addition of Pt to B2 NiAl will increase its bulk modulus B but decrease both its shear moduli C' and C44. Results from the model calculations were found to be in good agreement with experimental measurements on polycrystalline samples, as well as direct first-principles calculations on special quasirandom structures. no NU @ p-kolli @ 9711
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Tewari, S.N.; Vijayakumar, M.; Lee, J.E.; Curreri, P.A. Solutal partition coefficients in nickel-based superalloy PWA-1480 Journal Article 1991 Materials Science and Engineering A 141 1 97-102 Solutal profiles in dendritic single-crystal specimens of PWA-1480 nickel-base superalloy, which were directionally solidified and quenched, were examined on several transverse cross-sections to obtain the partition coefficients. Similar to their nickel-base binaries, the partition coefficients of tantalum, titanium, and aluminum were found to be less than unity; those of tungsten and cobalt were greater than unity. The partition coefficients were temperature independent in the range 1584-1608 K. The contribution of solid-state diffusion to microsegregation was observed to be negligible. no NU @ karnesky @ 9820
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Lee, W.-B.; Hong, S.-G.; Park, C.-G.; Park, S.-H. Carbide precipitation and high-temperature strength of hot-rolled high-strength, low-alloy steels containing Nb and Mo Journal Article 2002 Metallurgical and Materials Transactions A 33 6 1689-1698 Abstract  The effects of a Mo addition on both the precipitation kinetics and high-temperature strength of a Nb carbide have been investigated in the hot-rolled high-strength, low-alloy (HSLA) steels containing both Nb and Mo. These steels were fabricated by four-pass hot rolling and coiling at 650C, 600C, and 550C. Microstructural analysis of the carbides has been performed using field-emission gun transmission electron microscopy (TEM) employing energy-dispersive X-ray spectroscopy (EDS). The steels containing both Nb and Mo exhibited a higher strength at high temperatures (â¼600 C) in comparison to the steel containing only Nb. The addition of Mo increased the hardenability and led to the refinement of the bainitic microstructure. The proportion of the bainitic phase increased with the increase of Mo content. The TEM observations revealed that the steels containing both Nb and Mo exhibited fine (<10 nm) and uniformly distributed metal carbide (MC)-type carbides, while the carbides were coarse and sparsely distributed in the steels containing Nb only. The EDS analysis also indicated that the fine MC carbides contain both Nb and Mo, and the ratio of Mo/Nb was higher in the finer carbides. In addition, electron diffraction analysis revealed that most of the MC carbides had one variant of the B-N relationship ((100)MC//(100)ferrite, [011]MC//[010]ferrite) with the matrix, suggesting that they were formed in the ferrite region. That is, the addition of Mo increased the nucleation sites of MC carbides in addition to the bainitic transformation, which resulted in finer and denser MC carbides. It is, thus, believed that the enhanced high-temperature strength of the steels containing both Nb and Mo was attributed to both bainitic transformation hardening and the precipitation hardening caused by uniform distribution of fine MC particles. no NU @ p-kolli @ 9838
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Lee, B.C.; Park, J.K. Effect of the addition of Ag on the strengthening of Al3Li phase in Al-Li single crystals Journal Article 1998 Acta Materialia 46 12 4181-4187 The variation of the critical resolved shear stress as a function of aging condition has been measured in ternary Al-~(1.9-2.0) wt% Li-~0.4 wt% Ag single crystals and has been analyzed using the same version of order-hardening theory as in our previous work in binary single crystals. The result showed that the antiphase boundary energy of the Al3Li lattice on {111} definitively increases from about 0.118 J/m2 in binary crystals to 0.128+/-0.012 J/m2 in ternary crystals, in good agreement with the analysis of the transition behavior from shearing to looping and of the dislocation pair spacings. A strong segregation tendency of Ag into the Al3Li lattice is believed to be responsible for this increment. Our previous result of [gamma]apb (0.118+/-0.006 J/m2) in binary crystals is, although unlikely from the recent suggestion of Nembach, the best value one can obtain from the recent knowledge of order-hardening theory. This is slightly larger than that (about 0.100 J/m2) obtained from the analysis of the transition from shearing to looping and somewhat larger than the result (about 0.085 J/m2) of the first-principles calculation. Three factors are discussed as principal causes of a possibility of an overestimation of [gamma]apb on applying order-hardening theory. no NU @ karnesky @ 9941
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Kim, Y.-C.; Adusumilli, P.; Lauhon, L.J.; Seidman, D.N.; Jung, S.-Y.; Lee, H.-D.; Alvis, R.L.; Ulfig, R.M.; Olson, J.D. Three-dimensional atomic-scale mapping of Pd in Ni[sub:1 - x]Pd[sub:x]Si/Si(100) thin films Journal Article 2007 Applied Physics Letters Appl. Phys. Lett. 91 11 113106:1-3 annealing; interface roughness; nickel compounds; palladium compounds; rapid thermal processing; semiconductor-metal boundaries Atom-probe tomography was utilized to map the three-dimensional distribution of Pd atoms in nickel monosilicide thin films on Si(100). A solid-solution Ni0.95Pd0.05 film on a Si(100) substrate was subjected to rapid thermal processing plus steady-state annealing to simulate the thermal processing experienced by NiSi source and drain contacts in standard complementary metal-oxide-semiconductor processes. Pd is found to segregate at the (Ni0.95Pd0.05)Si/Si(100) heterophase interface, which may provide a previously unrecognized contribution to monosilicide stabilization. The silicide-Si heterophase interface was reconstructed in three dimensions on an atomic scale and its chemical roughness was evaluated. Aip no NU @ karnesky @ 9944
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