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In this study, the effects of adding Sn nanopowder (particle size < 150 nm) to three solder pastes SAC3-X(H)F3+, SCAN-Ge071-XF3+, and water washable WW50-SAC3 are evaluated regarding microstructure, morphology, joint strength, and electrical resistance. The nanopowder was added at a rate of 10% by weight and then mechanically mixed until homogenous solder paste was obtained. The results showed that the addition of Sn nanoparticles resulted in homogenous bond formation for SAC-3 and SCAN, while voids and bubbles formation slightly increased within the joint interface for the water washable solder paste. The SCAN + Sn nano reinforced solder paste showed increased variation of joint strength from 12.6 to 39.9 N, while the water washable + Sn nanopowder reinforced solder paste showed less variability in joint strength from 17.3 to 33.9 N. Both sets of solder paste with and without Sn nano reinforced solder paste showed a reliable quality joint under mechanical shock testing after six shocks in six milliseconds with an 87.1 ms pulse duration. The results showed that Sn nanoparticles resulted in a small resistance change, while RDC values (in mΩ) slightly decreased for SAC and increased for SCAN and further increases for water washable solder paste.

While the bonding of molecular adsorbates to graphene has so far been characterized as physisorption, our study of adsorbed ammonia and water using near-edge X-ray absorption spectroscopy provides unambiguous evidence for a chemical contribution to the adsorption bond. We use the situation, unique to graphene, to characterize the unoccupied valence band states of the partners in the bond on the basis of the complementary adsorbate and substrate X-ray absorption K edges. New adsorbate-induced features on the substrate (carbon) K edge are interpreted as hybrid states in terms of a simple model of chemical interaction.

We use in situ scanning tunneling microscopy (STM) to investigate intercalation of the ferromagnetic 3d metals Ni and Fe underneath a graphene monolayer on Rh(111). Upon thermal annealing of graphene/Rh(111) with the deposited metal on top, we observe the formation of epitaxial monatomic nanoislands grown pseudomorphically on Rh(111) and covered by graphene. The size and shape of intercalated nanoislands is strongly influenced by the local spatial variation of the graphene-Rh bonding strength. In particular, the side length of the intercalated nanoislands shows maxima around discrete values imposed by the periodicity of the graphene moiré. Intercalation can be performed efficiently and without any visible damage of the graphene overlayer in the studied temperature range between 670 and 870 K. We identify the main intercalation path to be via diffusion through pre-existing lattice defects in graphene, accompanied by the second mechanism which is based on the material diffusion via metal-generated defects followed by the defect healing of the graphene lattice. We deem these graphene-capped and sharply confined ferromagnetic nanoislands interesting in the fields of spintronics and nanomagnetism., (© 2012 American Chemical Society)

Words and famous faces were tachistoscopically presented in bilateral view to normal right-handed subjects. A left visual field advantage was obtained for famous faces whether naming or recognition from an array was required and a right visual field advantage was obtained for words. While the finding of a left visual field advantage for the recognition of famous faces is consistent with studies of face recognition deficits in brain-damaged patients, a right visual field advantage for the recognition of famous faces has recently been reported in normal subjects. Possible explanations for this discrepancy are discussed.

Stories were elicited from 29 epileptic patients with generalized, simple partial, and complex partial seizures with bilateral, right, or left foci, and from 32 persons in two control groups. Four older epileptic patients with long histories of left complex partial seizures were verbose. Their stories involved trivial and subjective details, consistent with circumstantiality and suggesting the substrate for a hallucinatory syndrome.

Face-recognition ability has been claimed to be qualitatively different from other pattern-recognition abilities. One argument for this claim is the finding of a significant right hemisphere advantage for the recognition of upright but not inverted faces. However, this argument is justified only if this orientation-sensitive pattern is unique to faces. In the present study, comparable patterns of orientation-sensitive involvement of the right hemisphere are found for the recognition of faces and houses. This finding is interpreted as evidence for a right hemisphere schema formation capacity that is applied not only to upright faces but also to other familiar classes of stimuli in their canonical upright orientation. It is suggested that any greater right hemisphere involvement in the recognition of upright faces is due to our greater expertise at recognizing faces than other stimulus types. We also find evidence that only a subset of right-handed adults show orientation-sensitive right hemisphere involvement in the recognition of faces and houses: in particular, those dextrals with a characteristic hemispheric arousal asymmetry in favor of the right hemisphere. In contrast, dextrals with a characteristic arousal asymmetry in favor of the left hemisphere do not show significant visual field asymmetries for faces or houses in either upright or inverted orientations.

Evidence supporting individual variations in patterns of hemispheric involvement in the recognition of visuo-spatial and verbal stimuli among dextrals is reported. In Experiment 1, subjects' asymmetry scores on a task that was nonlateralized for the group as a whole were significantly correlated with their asymmetry scores on right-hemisphere-specialized tasks, including face recognition. In Experiment 2, subjects' asymmetry scores on a task that was nonlateralized for the group as a whole were significantly correlated with their asymmetry scores on a left-hemisphere-specialized word recognition task. These results suggest that individual dextrals' asymmetry scores on lateralized tasks are a joint function of a subject's underlying hemispheric specialization for that task and stable individual variations in asymmetric hemispheric reliance.