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41.
E. Cohen J. W. Commelin Pfeffer van 't Hoff Ladenburg Adie Tammann Raoult Naccari Ponsot H. N. Morse D. W. Horn J. C. W. Frazer B. S. Hopkins E. J. Hoffmann W. L. Kennon L. F. Lovelace W. W. Holland F. M. Rogers P. B. Dunbar B. Mears B. F. Lovelace Berkeley Hartley Barlow und L. Kahlenberg 《Fresenius' Journal of Analytical Chemistry》1909,48(4-5):273-278
Ohne Zusammenfassung 相似文献
42.
Letm(t)dt be a positive measure onR
+. We investigate the relations among the growth ofm, the growth of its moment sequence {yn}, the growth of its Bergman kernel functionk
x=Σγ{n/-1}x
n, and the growth of the kernel function associated to the measureK(t)
−1m(t) dt. For a large class of measures, we find that these quantities satisfy asymptotic relations similar to the simple exact
relations which hold in the model casem(t)=e
−1.
Supported in part by a grant from the National Science Foundation. 相似文献
43.
An investigation on thin Ta2O5 films patterning using argon ion beam etching (IBE) is presented. The etch rates are characterised by varying the angle of incidence of the beam onto the substrate. Ta2O5 gratings with a period of 2.2 μm (1.1 μm linewidth) and 0.25 μm thickness are fabricated using an angle of incidence of 0°. The resulting Ta2O5 grating cross sectional profiles are analysed using AFM and SEM imaging. A fabrication method is thus demonstrated which could be used to implement wavelength selective gratings in applications such as grating-assisted directional couplers (GADCs). 相似文献
44.
Herbert L. Holland Peter R. Andreana Reza Salehzadeh-Asl Aaron van Vliet Nancy J. Ihasz Frances M. Brown 《Monatshefte für Chemie / Chemical Monthly》2000,40(5):667-672
Biotransformation of a series of racemic N-benzoyl α-amino acids by the fungus Beauveria bassiana ATCC 7159 results in isolation of the corresponding D-amino acid benzamides in high enantiomeric purity and yield. 相似文献
45.
46.
Jagdeep S. Sagu K.G. Upul Wijayantha Paul Holland Mallika Bohm Siva Bohm Tapan Kumar Rout Hemaka Bandulasena 《Crystal Research and Technology》2016,51(8):466-474
Carbon emissions from industrial sources are of major global concern, especially contributions from the steel manufacturing process which accounts for the majority of emissions. Typical blast furnace gases consist of CO2 (20‐25%), CO (20‐25%), H2 (3‐5%) and N2 (40‐50%) and trace amounts of other gases. It is demonstrated that gas mixtures with these compositions can be used at atmospheric pressure to grow carbon nanotubes (CNTs) by chemical vapor deposition (CVD) on to steel substrates, which act as catalysts for CNT growth. Computational modelling was used to investigate the CNT growth conditions inside the CVD chamber. The results show that industrial waste pollutant gases can be used to manufacture materials with significant commercial value, in this case CNTs. 相似文献
47.
The new ligand cis,cis-1,3,5-tris-(E)-(tolylideneimino)cyclohexane (TACH-o-tolyl) forms a 1:1 complex with iron(II). Addition of substituted phenolates forms 1:1:1 ligand:iron:phenolate complexes, which have been characterized both in the solid state and in solution. There is complete binding of the phenolate to the complex only when there are ortho-halogens on the phenolate. The tertiary complexes with ortho-halo-substituted phenolates exhibit short Fe-halogen distances, and the complex containing a non-coordinating but similarly sized ortho-methyl phenolate has a significantly different conformation and coordination geometry. Therefore, it is likely that the metal-halogen interaction stabilizes the complexes. The iron(II)-halogen interaction in these complexes may explain the substrate specificity of PcpA and LinE, enzymes that preferentially bind phenols and hydroquinones containing halogen substituents in ortho positions. 相似文献
48.
Clemens JB Chagarov EA Holland M Droopad R Shen J Kummel AC 《The Journal of chemical physics》2010,133(15):154704
The reaction of trimethyl aluminum on the group III rich reconstructions of InAs(0 0 1) and In(0.53)Ga(0.47)As(0?0?1) is observed with scanning tunneling microscopy/spectroscopy. At high coverage, a self-terminated ordered overlayer is observed that provides the monolayer nucleation density required for subnanometer thick transistor gate oxide scaling and removes the surface Fermi level pinning that is present on the clean InGaAs surface. Density functional theory simulations confirm that an adsorbate-induced reconstruction is the basis of the monolayer nucleation density and passivation. 相似文献
49.
Tayler AB Holland DJ Sederman AJ Gladden LF 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2011,212(1):1-10
Although biomolecular dynamics has been investigated using NMR for at least 40 years, only in the past 20 years have internal motions been characterized at atomic resolution throughout proteins and nucleic acids. This development was made possible by multidimensional heteronuclear NMR approaches that provide near complete sequential signal assignments of uniformly labeled biomolecules. Recent methodological advances have enabled characterization of internal dynamics on timescales ranging from picoseconds to seconds, both in solution and in the solid state. The size, complexity and functional significance of biomolecules investigated by NMR continue to grow, as do the insights that have been obtained about function. In this article I review a number of recent advances that have made such studies possible, and provide a few examples of where NMR either by itself or in combination with other approaches has paved the way to a better understanding of the complex relationship between dynamics and biomolecular function. Finally, I discuss prospects for further advances in this field. 相似文献
50.
Thermographic signal reconstruction for vibrothermography 总被引:1,自引:0,他引:1
Stephen D. Holland 《Infrared Physics & Technology》2011,54(6):503-511
Vibrothermography, also known as thermosonics or sonic infrared, is a method of nondestructive evaluation that finds cracks or delaminations from the heat given off in response to vibration. In vibrothermography, finding cracks requires identifying and localizing pulsed surface and subsurface heat sources from a time sequence of infrared images. Traditionally this identification involves manually stepping through and studying the images. Careful observation of the heating and subsequent cooling is needed to distinguish cracks from false indications. In this paper, we present an algorithm that reduces the entire time sequence to a single static plot. The plot uses only a few coefficients per pixel to reconstruct the original sequence; this is possible because the reduction is based on a physical model. As an added bonus, the algorithm reduces noise and improves sensitivity. A single false-color image summarizes all the information from the entire sequence, simplifying the task of identifying cracks. 相似文献