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1.
D. De Salvador A. Coati E. Napolitani M. Berti A.V. Drigo M.S. Carroll J.C. Sturm J. Stangl G. Bauer L. Lazzarini 《Applied Physics A: Materials Science & Processing》2002,75(6):667-672
In this work we investigate the diffusion and precipitation of supersaturated substitutional carbon in 200-nm-thick SiGeC
layers buried under a silicon cap layer of 40 nm. The samples were annealed in either inert (N2) or oxidizing (O2) ambient at 850 °C for times ranging from 2 to 10 h. The silicon self-interstitial (I) flux coming from the surface under
oxidation enhances the C diffusion with respect to the N2-annealed samples. In the early stages of the oxidation process, the loss of C from the SiGeC layer by diffusion across the
layer/cap interface dominates. This phenomenon saturates after an initial period (2–4 h), which depends on the C concentration.
This saturation is due to the formation and growth of C-containing precipitates that are promoted by the I injection and act
as a sink for mobile C atoms. The influence of carbon concentration on the competition between precipitation and diffusion
is discussed.
Received: 19 October 2001 / Accepted: 19 December 2001 / Published online: 20 March 2002 / Published online: 20 March 2002 相似文献
2.
R. Sturm 《Mathematische Annalen》1873,6(3):241-263
Ohne Zusammenfassung 相似文献
3.
Rudolf Sturm 《Mathematische Annalen》1882,19(4):461-486
Ohne Zusammenfassung 相似文献
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6.
Reaction of Metal and Metalloid Compounds with Polyfunctional Molecules. XIX. Synthesis of Amidoborazines By reaction of 2-chloro-1,3,4,5,6-pentamethylborazin with silylated carbonic acid amides and thioamides resp. the corresponding amidoborazines are obtained. By reaction of lithiated hexamethyldisilazane with 2-chloro-1,3,4,5,6-pentamethylborazine, the 2-hexamethyldisilazanyl-1,3,4,5,6-pentamethylborazine is formed. 1H, 11B, and 19F n.m.r. spectra, mass spectra and characteristic i.r. group frequencies are reported. 相似文献
7.
A simple semiconductor gas sensor (TGS 812) is used for the on-line measurement and control of indole during the production of l-tryptophan from indole and l-serine with immobilized E. coli cells. Indole is estimated in the reactor gas space. In combination with an automatic indole supply system, a feed-batch process became possible. The indole concentration was monitored and kept within the optimal range (300–600 mg l?1). A simple gas-sensing electrode dipped in the reaction medium provides direct measurement of organic solvents and gases in the liquid. Such a system is suitable for on-line determination of ethanol (10–70 g l?1) during continuous production of ethanol with immobilized yeast cells. 相似文献
8.
Reaction of N-Alkyl-bis(difluorophosphoryl)amides, RN(POF2)2, with Silylated Nucleophiles and Et2NSF3 N-Alkyl-bis(difluorophosphoryl)amides, RN(POF2)2 (R = Me, Et), react in any case with silylated nucleophiles such as Me3SiOMe and Me3SiNEt2 under cleavage of the PNP bridge forming derivatives of di- and monofluorophosphoric acid. In their reaction with Et2NSF3 (RNPF3)2 and OPF3 or PF5, resp., are obtained. The compounds F2P(O)? NR? PF4 and RN(PF4)2 postulated as intermediates are not stable. 相似文献
9.
Leuenberger M Nyfeler P Moret HP Sturm P Indermuhle A Schwander J 《Rapid communications in mass spectrometry : RCM》2000,14(16):1552-1557
A new technique for measuring CO(2) concentration in air samples, based on mass spectrometry, is described as an alternative to the common gas chromatographic method. Using a dual inlet isotope ratio mass spectrometer (IRMS), the ratio of the abundances of the m/z peaks 44 and 28 is determined. The precision of measurements (standard deviation <3 ppmv) is generally as good as the analysis with gas chromatography for small air samples (<1 ml STP of air). A major advantage of this new method is the possibility of parallel elemental and isotopic measurements of many air components. The technique is further improved by new wide mass range mass spectrometers allowing simultaneous intensity measurements of several m/z values between 28 and 44, resulting in an uncertainty of <0.5 ppm. The precision is somewhat limited by the production of N(2)O and NO(2) from N(2) and O(2) in the ion source, which accounts for about half of the signal strength at m/z 44. Copyright 2000 John Wiley & Sons, Ltd. 相似文献
10.
In this paper, we introduce a potential reduction method for harmonically convex programming. We show that, if the objective function and them constraint functions are allk-harmonically convex in the feasible set, then the number of iterations needed to find an -optimal solution is bounded by a polynomial inm, k, and log(1/). The method requires either the optimal objective value of the problem or an upper bound of the harmonic constantk as a working parameter. Moreover, we discuss the relation between the harmonic convexity condition used in this paper and some other convexity and smoothness conditions used in the literature.The authors like to thank Dr. Hans Nieuwenhuis for carefully reading this paper and the anonymous referees for the worthy suggestions. 相似文献