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A key limitation for the use of aluminum alloys in multi-material structural components is effective surface cleaning and texturing techniques to improve the quality of structural joints. In this study, the surface and sub-surface chemistries are investigated for a novel surface treatment method using laser interferometry produced by two beams of a pulsed Nd:YAG laser. Surfaces of AA 5128 aluminum alloy were treated using a two-beam laser interference setup, enabling the structuring of the surface at length scales much less than that of the laser beam. Periodic and patterned surface structures were created by the interference power profile through ablation of deposits and debris and melting and re-solidification of the near-surface region during laser-treatment. Chemical changes to the Al alloy surface induced by laser treatment were examined in detail in this study using both x-ray photoelectron spectroscopy (XPS) and scanning Auger microanalysis (SAM) as a function of number of interfering laser shots. XPS surface analysis indicates that this laser technique is effective at cleaning aluminum surfaces. Moreover, SAM data indicated that there is a compositional-induced variation of Mg due to laser-interference as Mg-rich areas were found in periodic interference-structured ridges. Notice: The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. The Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan (http://energy.gov/downloads/doe-public-access-plan). Unlabelled Image • Surface chemistry of aluminum alloy after two-beam laser interference processing • Compositional-induced variation of Mg due to laser-interference processing • Resolidification after laser interference processing enhances oxide growth. • Laser processing in air formed of an oxide layer different from the native oxide • Most adsorbed carbonaceous surface contaminants were removed, cleaning the surface. [ABSTRACT FROM AUTHOR]

Magnéli phases TinO2n−1 (3

Graphical abstract Highlights • Anatase N- and B- codoped TiO 2 with visible light activity was hydrothermally synthesized. • N and B atoms were introduced onto TiO 2 lattice via substitution and interstitial mechanisms. • Bisphenol A was successfully removed by simulated solar light/2.0NBT-350 in wastewater. • Six degradation byproducts, including two new compounds, were identified by LC/Q-TOF-ESI-MS. • Oxidation routes included hydroxylation, ring elimination, and opening. Abstract Hydrothermal technique was employed for the synthesis of N- and B-codoped TiO 2 at different atomic percentages and calcination temperatures (350 and 400 °C). Borane tert -butylamine complex was used as a novel precursor for the dopant atoms. The photocatalytic activities of catalysts were evaluated for destruction of bisphenol A (BPA) spiked in clean water and in secondary treated wastewater influent (SWI) collected from the Groundwater Replenishment System GWRS (Orange County, CA, USA), the world's largest water purification system for indirect potable reuse. Results of X-ray photoelectron spectroscopy (XPS) revealed the incorporation of N and B atoms onto TiO 2 lattice via substitution of O and/or Ti, and interstitial incorporation mechanisms. Carbon doping (graphite-like carbon; O-C = O) was also evidenced from XPS spectra. X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HR-TEM) revealed pristine TiO 2 and all doped TiO 2 existed in anatase structure. The anatase phase of catalysts was further confirmed by simulation of selected area electron diffraction (SAED) of the catalysts and reported anatase TiO 2 using the simulation software CrysTBox (v 1.10). Among all prepared catalysts, 2.0NBT-350 (N + B = 2.0%, calcination = 350 °C) possessed the smallest particle size (12.9 nm), largest BET surface area (108.5 m2/g) and highest visible-light absorption (i.e., λ > 400 nm). Simulated solar light/2.0NBT-350 system exhibited the maximum removal of BPA (0.1 μM) at the optimum catalyst dose of 0.8 g/L in clean water, over three consecutive degradation reuse cycles without any noticeable decrease in its photocatalytic activity. BPA was also successfully removed in SWI water, however with slower kinetics due to hydroxyl radical quenching effect of dissolved organic and inorganic species present in the SWI matrix. Degradation byproducts were identified by LC/Q-TOF-ESI-MS analysis. Six byproducts were found in the reaction mixture, with two compounds were newly identified in the current study. BPA oxidation routes comprised successive BPA hydroxylation, elimination of aromatic ring, ring opening, and cyclization of aliphatic compounds. This study is a promising demonstration for controlled design and synthesis of photocatalysts useful for environmental applications, especially for the treatment of BPA in wastewater effluents. [ABSTRACT FROM AUTHOR]

We have employed hard x-ray photoemission (HAXPES) to study a delta-doped SrTiO3 layer that consisted of a 3-nm thickness of La-doped SrTiO3 with 6% La embedded in a SrTiO3 film. Results are compared to a thick, uniformily doped La:SrTiO3 layer. We find no indication of a band offset for the delta-doped layer, but evidence of the presence of Ti3+ in both the thick sample and the delta-layer, and indications of a density of states increase near the Fermi energy in the delta-doped layer. These results further demonstrate that HAXPES is a powerful tool for the non-destructive investigation of deeply buried doped layers. [ABSTRACT FROM AUTHOR]

The article presents a study about the influence of pigment blends on the surface structure and surface chemistry of pigmented latex coatings in the U.S. The study uses coating that were prepared with different amounts of binder and were applied over two substrates with different absorption properties. In addition, an X-ray photoelectron spectroscopy was used to characterize the elemental composition of the surface layer. The study reveals that the latex retention mechanism of the pigmented coating increases the movement of latex particles towards the surface.

The article presents information about the Cornell High Energy Synchrotron Source (CHESS) User Meeting held on June 14 and 15, 2005 at the Cornell University, New York. Sol Gruner, CHESS director, gave an overview of the achievements of the most recent running period and the status of the Energy Recovery Linac, Cornell's next-generation X-ray photon source project. A structure-based design of drugs to treat AIDS, in particular inhibitors of HIV reverse transcriptase, was spoken about by Eddy Arnold, researcher at Rutgers University, New Jersey. Robert Thorne, Physicist at Cornell University discussed sample handling and cooling of macro-molecular crystals for data collection.

Fabric and foam samples from popular children car seats marketed in the United States during 2018 were tested for fluorine content by particle-included gamma ray emission spectroscopy (PIGE, n = 93) and X-ray photoelectron spectroscopy (XPS, n = 36), as well as for per- and polyfluoroalkyl substances (PFAS) by liquid and gas chromatography mass spectrometry (LC/MS and GC/MS, n = 36). PFAS were detected in 97% of the car seat samples analyzed with MS, with total concentrations of 43 PFAS (∑PFAS) up to 268 ng/g. Fabric samples generally had greater ∑PFAS levels than foam and laminated composites of foam and fabric. The three fabric samples with the highest total fluorine content as represented by the highest PIGE signal were also subjected to ultraviolet (UV) irradiation and the total oxidizable precursor (TOP) assay. Results from these treatments, as well as the much higher organofluorine levels measured by PIGE compared to LC/MS and GC/MS, suggested the presence of side-chain fluorotelomer-based polymers (FTPs), which have the potential to readily degrade into perfluoroalkyl acids (PFAAs) under UV light. Furthermore, fluorotelomer (meth)acrylates were found to be indicators for the presence of (meth)acrylate-linked FTPs in consumer products, and thus confirmed that at least half of the tested car seats had FTP-treated fabrics. Finally, extraction of selected samples with synthetic sweat showed that ionic PFAS, particularly those with fluorinated carbons ≤8, can migrate from fabric to sweat, suggesting a potential dermal route of exposure. Image 1 • 42 per- and polyfluoroalkyl substances (PFASs) were analyzed in children car seats. • Fabric samples generally had greater ∑PFASs levels than foam and composites. • Data suggest the presence of side-chain fluorotelomer-based polymers (FTPs), which can readily degrade. • PFASs of emerging concern significantly contributed to children exposure. Data suggest the presence of side-chain fluorotelomer-based polymers (FTPs), which can readily degrade. PFAS of emerging concern in car seats contribute to children exposure. [ABSTRACT FROM AUTHOR]