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At the intersection of multipolar, multi-scalar sites of mutual exchange and tension, Afghanistan and Iraq conjure imaginaries of shadowy and risky geographies wired up to dispersed terrorist cells around the globe. These spaces constitute the sites where the “civilizing process” of the “War on Terror” takes place, “laboratories of globalization” where global hegemonic neoliberal projects of free market democratization and development get stranded. At the same time, they are spaces where global interconnections are accelerated, and where multiple mobilities, often contingent upon expectations about the successes and failures of reconstruction, are interwoven, producing networks that extend well beyond national borders.

Alkaline-earth phosphates efficient in the dehydration of lactic acid to acrylic acid were previously shown to contain a surface mono/dihydrogen phosphate amorphous layer composed of M2+cations and both P═O and POH groups. In this work, acidic properties of such a layer were determined combining Fourier transform infrared (FTIR) spectra achieved at the dehydrated state and under water vapor and density functional theory (DFT) simulations of nondefective and defective MPOH structure. The FTIR spectra of adsorbed pyridine and lutidine revealed the presence of moderate Lewis acid sites (LAS) and of POH groups interacting by H-bonding without significant protonation. DFT calculations were key to interpret FTIR spectra after adsorption of NH3: when solely adsorbed, NH3interacts with the LAS on both the nondefective surface and the defective surface, whereas the POH for which H points up toward the gas phase are reoriented downward. Brønsted acid sites (BAS) were shown to form under water vapor. This phenomenon was shown by DFT to arise from a more acidic character of HPO42–species for the nondefective surface and casual formation of nondefective surface leading to higher amount of H2PO4–species, which are more acidic BAS.

The course of the conversion reaction during the electrochemical insertion/deinsertion of lithium in CuO thin film electrodes was surveyed by cyclic voltammetry (CV) and X-ray photoelectron spectroscopy (XPS). The electrochemical processes were studied through the comprehensive acquisition and interpretation of XPS and Auger spectra (Cu 2p, O 1s, Cu LMM) recorded at different stages of the first cycle of a Li/CuO cell. The reduction process consisting of three main steps leads successively to Cu+and Cu0and involves a Li2O2peroxide type phase as an intermediate, whereas Li2O is the main lithiated oxide at the end of the discharge. Only the two last steps appear reversible in charge. No evidence of Cu2+was found at the end of the charge at 3.5 V/Li+/Li, showing the irreversibility of the first step in our experimental conditions. Complementary XPS depth profile analyses were performed to check the evolution of the active material composition over the thickness of the electrode.

This study was performed to estimate the pool of SCFA produced in the digestive tract of growing pigs after the consumption of diets containing dif-ferent sources of resistant starch (RS) (15 g per meal) (potato starch (PoS), high amylose maize starch (HS) and retrograded extruded HS (RHS)). SCFA production in vitro was respectively 19, 23 and 21 mmol g^-1 of fermented PoS, HS and RHS. The highest butyric acid production was observed with PoS. Fifty six, 36 and 19% respectively of ingested PoS, HS and RHS escaped digestion in the small intestine, whereas residual starch was completely fermented in the large bowel. Luminal total SCFA in the caeco-colon 7 h after the experimental meal were respectively 33, 78 and 105 mmol for PoS, HS and RHS, with PoS providing the highest production of butyric acid. Theoretical in vivo SCFA production, calculated on the basis of results for in vitro fermentation and ileal digestibility, differed from in vivo results for PoS (+65%) and HS (-13%), but not for RHS. This study reveals different rates of disappearance of RS both in vitro and in vivo. © 1998 SCI.