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581.
In order to investigate the surface heterogeneity of silicon oxynitride films, we observed the nanoscale variation of the surface potential by Kelvin probe force microscopy (KFM), the molecular bonding characteristics by Fourier transform infrared spectrometry (FTIR), and the wetting behavior by contact angle measurement. Nitrogen incorporation into silicon oxynitride films influenced the decrease in the surface potential and the polar component of the surface free energy. We present the first correlation between the nanoscale measurement of the surface potential and the macroscopic measurement of the surface free energy in silicon oxynitride films grown by a standard plasma‐enhanced chemical vapor deposition (PECVD) technique. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
582.
E. Bauer A. Galatanu H. Michor G. Hilscher P. Rogl P. Boulet H. Noël 《The European Physical Journal B - Condensed Matter and Complex Systems》2000,14(3):483-493
A series of compounds , , were synthesised by reaction sintering. From Rietveld refinements isotypism was determined in all cases with the -(skutterudite)-type, space group - No. 204. These refinements also served to derive the Yb-content in the samples. There is a systematic trend for the Yb-occupancy
in the parent lattice , revealing a gradual decrease of the Yb-content from x
=0.8 (), x
=0.5 (FeCo), x
=0.2 (Co), x
=0.1 (Rh) to (Ir). This dependency seems to correlate with the thermal stability of the ternary compounds: a true ternary compound forms
for , whilst for stable binary skutterudite compounds already exist. Measurements of various bulk properties revealed the absence of any long range magnetic order in this series
of compounds. While the samples rich in Yb behave metallic like, the Rh and Ir based skutterudites show a semiconducting-like
resistivity which at lower temperatures is characterised by variable range hopping in the presence of strong Coulomb interaction.
Although exhibits a Seebeck coefficient up to about 150 μV/K, figures of merit ZT generally are below 0.1 near room temperature, primarily due to the large resistivities of the sintered material.
Received 15 July 1999 相似文献
583.
McCuen HB Noé MS Sierzchala AB Higson AP Caruthers MH 《Journal of the American Chemical Society》2006,128(25):8138-8139
A novel solid-phase phosphoramidite-based method has been developed for the synthesis of borane phosphonate DNA. Keys to this new approach are replacement of the common 5'-dimethoxytrityl blocking group with a 5'-silyl ether and the use of new protecting groups on the bases (adenine, N6-dimethoxytrityl; cytosine, N4-trimethoxytrityl; guanine, N2-[9-fluorenylmethoxycarbonyl]; thymine, N3-anisoyl). Because of these developments, it is now possible for the first time to synthesize oligodeoxynucleotides having any combination of the four 2'-deoxynucleosides and both phosphate and borane phosphonate internucleotide linkages (including oligomers having exclusively borane phosphonate linkages). 相似文献
584.
I. Brivio M. B. Gavela L. Merlo K. Mimasu J. M. No R. del Rey V. Sanz 《The European Physical Journal C - Particles and Fields》2017,77(8):572
We study the leading effective interactions between the Standard Model fields and a generic singlet CP-odd (pseudo-) Goldstone boson. Two possible frameworks for electroweak symmetry breaking are considered: linear and non-linear. For the latter case, the basis of leading effective operators is determined and compared with that for the linear expansion. Associated phenomenological signals at colliders are explored for both scenarios, deriving new bounds and analyzing future prospects, including LHC and High Luminosity LHC sensitivities. Mono-Z, mono-W, W-photon plus missing energy and on-shell top final states are most promising signals expected in both frameworks. In addition, non-standard Higgs decays and mono-Higgs signatures are especially prominent and expected to be dominant in non-linear realisations. 相似文献
585.
586.
Development and calibration of a WDXRF routine applied to provenance studies on archaeological ceramics
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Elemental analysis of ancient ceramics is primarily used in provenance research, where defined compositional groups are attributed to particular raw materials sources or production locations. Requirements in data quality and analytical performance are high, as is the need for clear and reproducible methodologies and the availability of information on the above to ensure interlaboratory comparability and long‐term data validity. This paper outlines the measurement parameters of a dedicated calibration set‐up for the analysis of ancient ceramics using wavelength‐dispersive X‐ray fluorescence spectrometry. The specimens are prepared as concentrated glass beads, allowing the measurement of 26 elements from a single sample, thus minimising sample size requirements. Certified and non‐commercial standards are used to evaluate the performance of the method in terms of detection limits, precision, repeatability and accuracy. The materials used cover a range of compositions in line with the matrix variability encountered in archaeological ceramics. The data confirm the high standard of the method and highlight specific limitations. An initial assessment of comparability with other set‐ups used in ceramic analyses, primarily neutron activation analysis, is given through a discussion of performance on commonly analysed materials. The advantages of the proposed method include excellent analytical performance, analysis of a large suite of elements including all major, minor and a good range of traces, relatively small sample sizes and preparation of samples that can be stored and reanalysed. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
587.
Noël R Vanucci-Bacqué C Fargeau-Bellassoued MC Lhommet G 《The Journal of organic chemistry》2005,70(22):9044-9047
[reaction: see text] The preparation of new chiral 6-carbonyl 2,3,8,8a-tetrahydro-7H-oxazolo[3,2-a]pyridines by an efficient two-step procedure is described. 相似文献
588.
彭苏文 《光谱学与光谱分析》1993,13(3):45-50
本文研究了柱芯电极测定西藏斑岩铜矿中8个主次要元素,并与用其他电极测定的结果进行了对比实验。本文还讨论了组分影响及消除方法。对铜矿区样品测定,其RSD(n=15)为Cu±3.3%,Mo±4.1%,Ag±3.7%,Pb±6.5%。Zn±6.5%,As±7.3%,W±6.9%以及Bi±6.9%。用化学分析,外检和标样验证了方法的可靠性。 相似文献
589.
Irène Gijbels Paul Janssen Noël Veraverbeke 《Probability Theory and Related Fields》1988,77(2):179-194
Summary Weak and strong representations are proved for two classes of trimmed U-statistics, generalizing the trimmed mean. Applications of the strong representation theorems include laws of iterated logarithm and invariance principles for trimmed U-statistics. 相似文献
590.
用于激光等离子体诊断的硬X光能谱仪 总被引:1,自引:1,他引:0
介绍了利用滤片和探测器阵列组合的硬X光能谱仪(简称FFS)的工作原理,结构性能和数据处理。文章最后给出了FFS在惯性约束聚变(ICF)实验中测到的硬X光谱的典型结果。 相似文献