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M. B. Freiler M. C. Shih S. Kim M. Levy I. P. Herman R. Scarmozzino R. M. Osgood Jr. 《Applied Physics A: Materials Science & Processing》1996,63(2):143-151
We present a study of pattern-transfer and etch-induced damage in photon-induced cryoetching. Features with effective radii as small as 100 nm have been formed in both bulk and layered GaAs/AlGaAs materials. A measurement of the photoluminescence of etch-defined deep- submicrometer structures material suggests that this form of etching results in minimal process-induced damage. Modeling of the luminescence vs feature size for these features shows that the luminescence is limited only by carrier diffusion and non-radiative surface recombination. 相似文献
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The rate of laser photochemical reactions on surfaces can be enhanced over their gas-phase values by the interplay of a number of surface phenomena. These effects include simple increases in molecular density due to physisorption, spectral shifts in the adsorbed phase, and enhancement in the optical electric field due to surface contouring. 相似文献
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W. F. Osgood 《Monatshefte für Mathematik》1896,7(1):90-92
Ohne ZusammenfassungAuszug aus einem Schreiben an Herrn O. Stolz. 相似文献
7.
Subbiah Meenakshisundaram RM. Sockalingam 《Journal of molecular catalysis. A, Chemical》2000,160(2):269-275
Catalytic activity of Os(VIII) in the oxidation of some twenty organic sulfides with sodium salt of N-chlorobenzenesulfonamide (CAB) has been investigated in alkaline (pH8.7) t-butanol–water (1:1 v/v) medium. Significant retarding influence of [OH−] on the reactivity is exhibited. The catalysed reaction is strongly accelerated in the presence of Hg(II). Imperfections are observed in the linear Hammett relationship in the case of –NO2 substituents. 相似文献
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Charles F. Osgood 《Monatshefte für Mathematik》1986,102(1):7-25
This paper obtains effective lower bounds on the absolute values of linear forms, over the integers, in power products of values of certain SiegelE-functions or SiegelG-functions. The bounds obtained are in terms of the product of the absolute values of the coefficients. ForE-functions the bound obtained is a best possible result, up to an arbitrarily small positive epsilon. ForG-functions the result is asymptotically best in the following sense: for each epsilon larger than zero there exists an integerN such that ifz, the point of evaluation, equalsM
–1 whereM is an integer with absolute value larger thanN, then the bound obtained is within epsilon of a best possible bound. (From the proof it is clear thatz need not be the inverse of an integer. What is necessary that the absolute value of its numerator must be much smaller than the absolute value of its denominator.)Results obtained recently by D. V. andG. V. Chudnovsky bounding the absolute values of similar forms give bounds in terms of the maximum of the absolute values of the coefficients; such lower bounds can be much smaller.Dedicated to Professor E. Hlawka on the occasion of his seventieth birthday 相似文献
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Nano titanium dioxide (nTiO2), generally considered to be toxicologically inert, is manufactured in large quantities and extensively applied in consumer products. The small size and large surface area endow them with an active group or intrinsic toxicity. Advances in instrumentation are making Raman spectroscopy the tool of choice for an increasing number of (bio) chemical applications. One of the great advantages of this technique is its ability to provide information on the concentration, structure and interaction of biochemical molecules in their microenvironments within intact cells and tissues, non-destructively. Zebrafish (Danio rerio), one of the most important vertebrate model organisms used in developmental biology, are increasingly used in biomedical research, particularly as a model of human disease. In the present work, an attempt is made to study the effect of titanium dioxide, both nano and bulk, on the microenvironment of the liver tissues of Zebrafish using FT-Raman spectroscopy. The results of the present study suggest that TiO2 exposure demonstrate a marked influence on the microenvironments of the liver tissues of Zebrafish. A shift to a higher wavenumber and an increase in the intensity of the band at ∼1087 cm−1 in the TiO2 exposed tissues suggest that some of the conformational changes resulting from the alkali recovery process takes place due to TiO2 exposure. The decreased intensity ratio (I3220/I3400) observed in the titanium-exposed tissues suggests a decreased water domain size, which could be interpreted in terms of weaker hydrogen-bonded molecular species of water in the TiO2 exposed tissues. The observed shift of COO− bands to higher frequencies shows the disruption of salt bridges as a result of a change in the oppositely charged partners and due to the enhanced random coil conformation. The variation in the intensity ratio of the tyrosyl doublet (I858/I825) indicates variation in the hydrogen bonding of the phenolic hydroxyl group due to TiO2 exposure. The results further suggest that the microenvironments are greatly altered due to titanium nano exposure when compared to titanium bulk. In conclusion, the results indicate that FT-Raman spectroscopy might be a useful tool for rapid assessment of nano particle biological interactions. 相似文献
10.
We have investigated the output behaviour of a low temperature HyBrID-type copper laser operating with a flowing Ne–HCl reactive
gas mixture. 15.5 W of average power was observed from a 19 mm bore device at 23 kHz PRF corresponding to a specific output
power of 78 mW/cm3. The output power was 20–30% lower than that of the same device operating with an Ne–HBr mixture; however,
it markedly exceeds the output of similar sized elemental copper vapour lasers (with or without hydrogen additive).
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献