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11.
Ratto F Locatelli A Fontana S Kharrazi S Ashtaputre S Kulkarni SK Heun S Rosei F 《Physical review letters》2006,96(9):096103
We report a low energy electron microscopy study of the relation between self-organized Ge/Si(111)nanostructures and their local environment. By comparison with Monte Carlo simulations, three-dimensional islands are shown to display a substantial tendency towards self-ordering. This tendency may result from the diffusive nature of the nucleation processes. The size of individual nanostructures does not significantly correlate with the distance between neighboring islands. Thus energetic factors are thought to govern the competition among coexisting nanostructures to capture the deposited mass. 相似文献
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In this paper, we construct a new family of harmonic morphisms ${\varphi:V^5\to\mathbb{S}^2}In this paper, we construct a new family of harmonic morphisms
j:V5?\mathbbS2{\varphi:V^5\to\mathbb{S}^2}, where V
5 is a 5-dimensional open manifold contained in an ellipsoidal hypersurface of
\mathbbC4 = \mathbbR8{\mathbb{C}^4\,=\,\mathbb{R}^8}. These harmonic morphisms admit a continuous extension to the completion V*5{{V^{\ast}}^5}, which turns out to be an explicit real algebraic variety. We work in the context of a generalization of the Hopf construction
and equivariant theory. 相似文献
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The absolute absorption cross section and photodissociation quantum yield of NO2 were determined over the wavelength region 375 to 420 nm at a temperature of 296 K. The quantum yield measurements were made at 1 nm intervals over this frequency range with an accuracy of ± 7%. The data show a significant decrease in the quantum yield between 380 and 390 nm indicating the possibility of a non-dissociating NO2 excited state in this region. 相似文献
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Lucas Andreo Carla A. Soldera Beatriz Guimares Ribeiro Patrick Raoul Vicente de Matos Paola Bindes Sousa Weslley Wallace de Alcntara Araújo Amorim Anna Carolina Ratto Tempestini Horliana Sandra Kalil Bussadori Kristianne Porta Santos Fernandes Raquel Agnelli Mesquita‐Ferrari 《Photochemistry and photobiology》2019,95(3):879-885
A peripheral nerve injury (PNI) can result in motor or sensory disorders. Low‐level laser therapy (LLLT) has demonstrated positive results as a treatment option for PNI. Wistar rats were divided into five groups: Control, Injury, Injury + LLLTn (nerve), Injury + LLLTm (muscle) and Injury + LLLTn + m (nerve and muscle irradiation). The groups were analyzed after one, two, three and four weeks. PNI was achieved by crushing the sciatic nerve. Laser treatment (780 nm, 3.2 J) was realized over the nerve and/or tibialis anterior muscle. In gait analyses, the groups irradiated over the nerve demonstrated an improvement after two weeks. In the analysis of mechanical sensitivity, the Injury + LLLTn demonstrated a reduction after one week in comparison with Injury group; the Injury + LLLTn + m and Injury + LLLTm demonstrated an increase after two weeks in comparison with Injury group; and the irradiated groups demonstrated a reduction in nociception after four weeks in comparison with Injury group. In the analysis of muscle atrophy, the Injury + LLLTn demonstrated more muscle mass after two weeks. LLLT improves functional aspects related to gait, mechanical sensitivity and muscle mass, with better results regarding motor aspects and muscle mass when administered over the injured nerve and better results regarding sensory aspects when administered over the muscle. 相似文献
19.
D. B. Marshall R. E. DeWames P. E. D. Morgan J. J. Ratto 《Applied Physics A: Materials Science & Processing》1990,50(4):445-448
Hysteretic force-separation relations for Tl, Bi and Y based superconductors and a magnet are compared. The magnitudes of the forces, the hysteresis, and the magnetic stiffness were all largest in the three-layer Tl2Ba2Ca2Cu3Ox compound, indicating strong flux pinning. The hysteresis in both two and three layer thallium compounds was sufficient to generate attractive forces as the superconductor and magnet were moved apart. The use of remanent fields to improve stability of levitated and suspended magnets is described. 相似文献
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O'Neill BM Ratto JE Good KL Tahmassebi DC Helquist SA Morales JC Kool ET 《The Journal of organic chemistry》2002,67(17):5869-5875
We describe the preparation and structure of the deoxyribonucleoside of 4-fluoro-6-methylbenzimidazole, abbreviated dH (8), which acts as a close shape mimic of the nucleoside deoxyguanosine. The nucleoside is prepared from 2-fluoro-4-methylaniline in seven steps. The X-ray crystal structure reveals a (-sc) glycosidic orientation, an S conformation for the deoxyribose moiety, and quite close shape mimicry of guanine by the substituted benzimidazole. Conformational studies by (1)H NMR and (1)H-(1)H ROESY experiments reveal an S-type conformation and an anti glycosidic orientation in solution (D(2)O), essentially the same as that of deoxyguanosine. Base-stacking studies in a "dangling end" context reveal that the benzimidazole base mimic stacks more strongly than all four natural bases, and more strongly than its counterpart guanine by 1.1 kcal/mol. Base-pairing studies in a 12mer DNA duplex show that, like other nonpolar nucleoside isosteres, H is destabilizing and nonselective when paired opposite natural bases. However, when paired opposite another nonpolar isostere, difluorotoluene (F), a mimic of thymine, the pair exhibits stability approaching that of its natural analogue, a G-T (wobble) base pair. The nucleoside analogue dH will be useful in studies of protein-DNA interactions, and the H-F base pair will serve as a structurally and thermodynamically close mimic of G-T in studies of DNA mismatch repair enzymes. 相似文献