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The objective of this research was to investigate and compare the effects of various protein or protein-based powders (WPC, SPI, BSA and hemoglobin) addition on transform of texture properties in egg white (EW)/egg yolk (EY) gels. Results showed that the highest hardness value (38.5 N) was detected in BSA-treated EW gels, while the lowest values (46.6 N) were obtained in hemoglobin-treated EY gels. Additionally, significantly increased value of free –SH groups was obtained in SPI/BSA/hemoglobin-treated EW/EY solutions, and increased value of protein solubility was obtained in EY solutions treated by WPC/SPI/BSA/hemoglobin relative to those of the control. The EW solutions treated by BSA/hemoglobin reached significantly higher H0 values than those of other groups. SDS-PAGE analysis showed that the hemoglobin-treated EW solution had slightly intense bands of ovoinhibitor, ovotransferrin and ovalbumin, and the EY solutions treated by WPC/SPI/BSA had higher level of covalent crosslinking. The EW gels treated by WPC/hemoglobin exhibited relatively more ordered protein secondary structures (α-helix and β-sheet) than those of the SPI group. SEM results suggested that WPC/BSA-treated EW gels developed uniform, porous and fiber-like structure, while SPI/BSA-treated EY gels developed rougher structure.

Recent trends in semiconductor process engineering have resulted in significant adoption of new materials and processes to enable new paradigms in device manufacturing. One such emerging process is area selective deposition where a material can be selectively deposited on an area of interest. In this work, we have demonstrated selective deposition of ruthenium (Ru) on amorphous (a-Si) and polycrystallized silicon (p-Si) to silicon dioxide (SiO2) on both 2D blanket films as well as 3D annealed SiO2–Si multilayer stacks. Amorphous Si once crystallized using high temperature annealing exhibits reduced surface hydrogen content (–Si–H), yet we observed Ru growth on p-Si films that were annealed under multiple conditions (800, 900, and 1000 °C). We have used a combination of Fourier transform-infrared spectroscopy and x-ray photoelectron spectroscopy (XPS) to show that both –Si–H and film crystallinity impact the selective growth of Ru. We have also demonstrated selective deposition of ∼10 nm Ru on p-Si layers and ∼0 nm Ru on SiO2 layers of the annealed 3D SiO2–Si multilayer stack. Additionally, by using a combination of XPS and transmission electron microscopy, we have demonstrated that Ru growth is higher on nongrowth surfaces in 2D substrates than on 3D stacks. Finally, we have shown that this process technology can be further advanced using a combination of selective and nonselective conformal atomic layer deposition processes to develop a novel 3D annealed SiO2–Si multilayer stack, thereby demonstrating a 3D device with low –H content p-Si films. This study can help us to realize new integration schemes for innovative 3D device structures. [ABSTRACT FROM AUTHOR]

In an earlier report, flyability failures due to siloxanes were investigated comparing disks with either Z-Dol or X-1P lubricant. On the Z-Dol disk, the head-disk interface failed at 47 h (h) and the slider accumulated silicon oxide smears, whereas the X-1P disk did not fail (truncated at 300 h) and the slider remained clean. The contrasting performance was rationalized by an assumed mechanism in which degraded lubricant was essential. In this paper, we demonstrate that siloxanes can be tribochemically converted into silicon oxides without any lubricant on the disk or slider. Lubricant degradation is, therefore, not needed for the formation of silicon oxides from siloxanes. We find that siloxane oligomers on Z-Dol disks form micrometer-sized droplets 100 nm in height, whereas on X-1P disks, siloxanes spread out as a very thin film. The siloxane droplets on Z-Dol disks may lead to flyability failure because they exceed the fly height. The presence or absence of siloxane droplets on disk surfaces may be explained in terms of surface wetting properties characterized by contact angle measurements. Index Terms--Hard disk drive, head-disk interface, head smear, lubricant, silicon oxide, siloxane.

On Cu(110)-p(2×1)-O at 300 K SO[sub 2](g) reacts stoichiometrically with O(a) to form a surface covered with both c(4×2)-SO[sub 3] and p(2×2)-SO[sub 3] structures. With heating SO[sub 2](g) evolves from the surface in distinct reaction-limited states at 384 K, 425 K, and 470 K, and the surface reverts to its initially oxidized state. On Cu(110), SO[sub 2](g) adsorbs molecularly below 300 K; upon annealing to 300 K, the sulfur dioxide disproportionates according to 3SO[sub 2](a)→S(a)+2SO[sub 3](a) with concomitant desorption of excess SO[sub 2](a). The surface formed in this manner exhibits large c(2×2)-S domains which encompass scattered c(4×2)-SO[sub 3] and p(2×2)-SO[sub 3] structures in a 1:2 coverage ratio. After being annealed to 400 K, the surface exhibits large p(2×2)-SO[sub 3] domains surrounding smaller c(4×2)-SO[sub 3] and c(2×2)-S islands. Continued heating past 400 K results in decomposition of sulfite according to SO[sub 3](a)→SO[sub 2](g)+O(a), evolving sulfur dioxide at 470 K and leaving the surface covered with atomic sulfur and oxygen. Real-time STM images show the mobility of oxygen at island boundaries and the mobility of sulfite amid the p(2×1)-O structures. STM measurements suggest that the sulfite occupy four-fold hollow sites. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The CO-induced hex→(1×1) surface phase transition on Pt{100} is driven by the higher adsorption heat of CO on the (1×1) phase than on the hex phase and occurs by the sequential steps of CO adsorption on the hex phase and growth of islands of CO trapped on the (1×1) phase. We have investigated the dynamics of CO chemisorption on both the rotated hex (hex-R) and (1×1) surfaces by measuring the sticking probability as a function of surface temperature, beam energy, and beam incidence angle using the King and Wells beam reflectivity method. For both clean surfaces, the adsorption is nonactivated and there is no evidence for adsorption via an intrinsic precursor. However, at finite CO coverages, there is an additional adsorption pathway involving an extrinsic physisorbed precursor. At surface temperatures above 350 K, the net sticking probability on the initial hex-R surface at finite CO coverages is less than below 350 K due to CO desorption, primarily from the hex-R phase, competing with island growth. We have developed a technique to measure the local CO coverage on the hex-R phase during the CO-induced hex-R→(1×1) phase transformation. The island growth rate has a power law dependence on the local CO coverage on the hex-R phase with an apparent reaction order of 4.5±0.4. These kinetics manifest themselves as a strongly flux-dependent net sticking probability. The absence of a decrease in the local CO coverage on the hex-R phase after the onset of island growth is unexpected considering the nucleation-and-growth process, and two possible microscopic mechanisms for the surface phase transition are proposed. [ABSTRACT FROM AUTHOR]