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61.
62.
Magnetic properties and diffusion of adatoms on a graphene sheet 总被引:1,自引:0,他引:1
Lehtinen PO Foster AS Ayuela A Krasheninnikov A Nordlund K Nieminen RM 《Physical review letters》2003,91(1):017202
63.
The synthesis of the first mesogenic hexaalkoxybenzo[b]triphenylene derivative is reported; this compound exhibits a broad columnar liquid crystal phase at temperatures only slightly above room temperature. 相似文献
64.
Ohne Zusammenfassung 相似文献
65.
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Ohne Zusammenfassung 相似文献
67.
A. Sulfrian M. Kapp Margaret D. Foster und E. V. Mills 《Fresenius' Journal of Analytical Chemistry》1933,95(1-3):105-107
Ohne Zusammenfassung 相似文献
68.
In situ ion beam sputter deposition and X‐ray photoelectron spectroscopy (XPS) of multiple thin layers under computer control for combinatorial materials synthesis
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Thomas A. Wilson Anders J. Barlow Michael L. Foster Mariela Bravo Sanchez Jose F. Portoles Naoko Sano Peter J. Cumpson Ian W. Fletcher 《Surface and interface analysis : SIA》2017,49(1):18-24
Deposition of ultra‐thin layers under computer control is a frequent requirement in studies of novel sensors, materials screening, heterogeneous catalysis, the probing of band offsets near semiconductor junctions and many other applications. Often large‐area samples are produced by magnetron sputtering from multiple targets or by atomic layer deposition (ALD). Samples can then be transferred to an analytical chamber for checking by X‐ray photoelectron spectroscopy (XPS) or other surface‐sensitive spectroscopies. The ‘wafer‐scale’ nature of these tools is often greater than is required in combinatorial studies, where a few square centimetres or even millimetres of sample is sufficient for each composition to be tested. The large size leads to increased capital cost, problems of registration as samples are transferred between deposition and analysis, and often makes the use of precious metals as sputter targets prohibitively expensive. Instead we have modified a commercial sample block designed to perform angle‐resolved XPS in a commercial XPS instrument. This now allows ion‐beam sputter deposition from up to six different targets under complete computer control. Ion beam deposition is an attractive technology for depositing ultra‐thin layers of great purity under ultra‐high vacuum conditions, but is generally a very expensive technology. Our new sample block allows ion beam sputtering using the ion gun normally used for sputter depth‐profiling of samples, greatly reducing the cost and allowing deposition to be done (and checked by XPS) in situ in a single instrument. Precious metals are deposited cheaply and efficiently by ion‐beam sputtering from thin metal foils. Samples can then be removed, studied and exposed to reactants or surface treatments before being returned to the XPS to examine and quantify the effects. Copyright © 2016 The Authors Surface and Interface Analysis Published by John Wiley & Sons Ltd. 相似文献
69.
Lau RK Ménard M Okawachi Y Foster MA Turner-Foster AC Salem R Lipson M Gaeta AL 《Optics letters》2011,36(7):1263-1265
We report the first demonstration of cw wavelength conversion from the telecommunications band to the mid-IR (MIR) region via four-wave mixing in silicon nanowaveguides. We measure a parametric bandwidth of 748 nm by converting a 1636 nm signal to produce a 2384 nm idler and show continuously tunable wavelength conversion from 1792 to 2116 nm. This report indicates that the advantages of silicon photonics may be leveraged to create devices for a large range of MIR applications that require cw operation. 相似文献
70.
Enzymatic hydrolysis of ammonia-treated sugar beet pulp 总被引:2,自引:0,他引:2
Foster Brian L. Dale Bruce E. Doran-Peterson Joy B. 《Applied biochemistry and biotechnology》2001,91(1-9):269-282
Sugar beet pulp is a carbohydrate-rich coproduct generated by the table sugar industry. Beet pulp has shown promise as a feedstock
for ethanol production using enzymesto hydroly zepolymeric carbohydrates and engineered bacteria to ferment sugars to ethanol.
In this study, sugar beet pulp underwent an ammonia pressurization depressurization (APD) pretreatment in which the pulp was
exploded by the sudden evaporation of ammonia in a reactor vessel. APD was found to substantially increase hydrolysis efficiency
of the cellulose component, but when hemicellulose- and pectindegrading enzymes wereadded, treated pulp hydrolysis was no
better than the untreated control. 相似文献