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The influence of lithium chloride (LiCl) on the hydration structure of anionic micelles of sodium dodecyl sulfate (SDS) in water was studied using the contrast-variation small-angle neutron scattering (SANS) technique. In the past, extensive computational studies have shown that the distribution of invasive water plays a critical role in the self-organization of SDS molecules and the stability of the assemblies. However, in past scattering studies the degree of the hydration level was not examined explicitly. Here, a series of contrast-variation SANS data was analyzed to extract the intramicellar radial distributions of invasive water and SDS molecules from the evolving spectral lineshapes caused by the varying isotopic ratios of water. By addressing the intramicellar inhomogeneous distributions of water and SDS molecules, a detailed description of how the counterion association influences the micellization behavior of SDS molecules is provided. The extension of our method can be used to provide an in-depth insight into the micellization phenomenon, which is commonly found in many soft matter systems.

TiO2 nanotube-based heterostructures grafted with ZnO nanorods, Ag nanoparticles, or Pd nanodendrites were synthesized for photocatalytic H2O/CH3OH splitting and H2 generation. Compared with P25 TiO2 nanoparticles and bare TiO2 nanotubes, these heterostructures, in particular, the one grafted with Pd nanodendrites, were found to present a markedly enhanced photocatalytic H2 generation efficiency (net H2 generation rate ∼143 μmol/h). Rather than the surface area of the photocatalysts, the lifetime (separation) of photogenerated carriers and, in particular, the surface plasmon resonance-stimulated carrier excitation dominated the number of total effective carriers. A power relationship with an exponent of 0.2 between the H2 generation rate and the number of total photogenerated carriers was determined, which suggests that the number of effective carriers or the efficiency in H2O/CH3OH splitting might decay in an exponential way.

Herein, we adopted alloying and rapid-dendrite-growth methods to improve the mechanical properties of Fe-based alloys. Three molten alloys including Fe-5Ni-5Mo-5Ge, Fe-5Ni-5Mo-5Ge-5Co, and Fe-5Ni-5Mo-5Ge-5Co-5Si were undercooled, during which (αFe) dendrites grew rapidly with the decrease of temperature (i.e., increase of undercooling). The rapid growth of (αFe) dendrites in the Fe-5Ni-5Mo-5Ge-5Co alloy at a high rate of 31.8 ms–1 caused by a large undercooling more effectively enhanced the microhardness than a Co addition did. In comparison, because of the great disparity of atom size and valence electron number between Fe and Si, a further Si addition suppressed the (αFe) dendrite growth while dramatically increasing the Vickers microhardness of the Fe-5Ni-5Mo-5Ge-5Co-5Si alloy to HV 622.

In situ nanoscopic observations of healthy and osteoporotic bone nanopillars under compression were performed. The structural-mechanical property relationship at the atomic scale suggests that cortical bone performance is correlated to the feature, arrangement, movement, distortion, and fracture of hydroxyapatite nanocrystals. Healthy bone comprising tightly bound mineral nanocrystals shows high structural stability with nanoscopic lattice distortions and dislocation activities. On the other hand, osteoporotic bone exhibits brittleness owing to the movements of dispersed minerals in and intergranular fracture along a weak organic matrix.

In this study, TiO2/SnO2−Pd heterostructures with enhan-ced photocatalytic activity were synthesized by the sensitization and activation of TiO2 nanotubes with SnO2−Pd nanoparticles. The growth of the SnO2−Pd nanoparticles was dominated by the crystal structures of the TiO2 nanotubes and the sensitization time. On 450 °C annealed anatase TiO2 nanotubes, grown SnO2−Pd nanoparticles were uniformly stacked in a layer with specific structural orientations of Pd(111)∥anatase TiO2(200) and SnO2(110)∥anatase TiO2(101). In contrast, on as-anodized amorphous TiO2 nanotubes, SnO2−Pd nanoparticles were randomly packed. The deposited rutile SnO2 nanoparticles induced the crystallization of amorphous TiO2 into a rutile phase with specific lattice correlations of Pd(111)∥rutile TiO2(101) and SnO2(110)∥rutile TiO2(110) during late-stage annealing at 450 °C. The rutile TiO2∥SnO2−Pd heterostructures had a lower photocatalytic efficiency in the degradation of methylene blue than did the anatase heterostructures but had a h...