High-resolution scanning tunneling microscopy (STM) images at 5 K, simultaneously resolving the molecular adsorbate and the honeycomb structure of the well-defined Ag[111]-p(4 x 4)+Ag(1.83)O substrate, assign the adsorption site for ethene on the silver oxide surface. Ethene molecules are exclusively adsorbed above a particular subset of Ag(delta)(+) sites in the hexagonal rings of the oxide. Extensive density functional theory (DFT) slab calculations confirm that this is the most stable site, with an adsorption energy of 0.4 eV (39 kJ mol(-1)). Adsorption is accompanied by a large deformation of the hexagonal oxide ring and a significant increase in the C-C bond length. STM image simulations provide qualitative agreement with the experimental images, and the molecular orientation is discussed with the help of simple molecular orbital arguments.

A simple and effective stepwise-method has been developed to remove defects from the top graphene layers of highly orientated pyrolytic graphite. Using a combination of ozone exposure and moderately high temperature we have shown that a defect-rich graphite surface can be modified to generate a graphene-like surface containing a negligible amount of oxygen, hydrogen and sp 3 carbon. We report definitive x-ray photoelectron and x-ray absorption spectroscopy analysis after each stage of the process, suggest a mechanism by which the modification occurs and propose it as a route towards the preparation or manipulation of pristine graphene samples.

High-pressure photoelectron spectroscopy is a rapidly developing technique with applications in a wide range of fields ranging from fundamental surface science and catalysis to energy materials, environmental science, and biology. At present the majority of the high-pressure photoelectron spectrometers are situated at synchrotron end stations, but recently a small number of laboratory-based setups have also emerged. In this paper we discuss the design and performance of a new laboratory based high pressure photoelectron spectrometer equipped with an Al Kα X-ray anode and a hemispherical electron energy analyzer combined with a differentially pumped electrostatic lens. The instrument is demonstrated to be capable of measuring core level spectra at pressures up to 30 mbar. Moreover, valence band spectra of a silver sample as well as a carbon-coated surface (graphene) recorded under a 2 mbar nitrogen atmosphere are presented, demonstrating the versatility of this laboratory-based spectrometer. © 2014 AIP Publishing LLC.[http://dx

The interaction of acetaldehyde with the Ag{111}-(4 × 4)-Ag1.83O surface oxide structure at temperatures between 77 and 200 K has been studied with scanning tunneling microscopy at 5 K. The bonding sites, relative to the oxide structure, of acetaldehyde at 77 K, and of acetate and ethane-1,1-dioxy formed after annealing to 170 K are discussed. Helical polyacetaldehyde chains formed at 140 K, previously proposed on the basis of RAIRS data, have been observed directly, coexisting with the oxide surface.

This report examines the dynamics and the complexation behaviour of 'acid porphyrin' systems in solution and provides a valuable insight into the mechanisms for both porphyrin protonation and metallation. The synthesis of mono-and bis-substituted porphyrins appended with long alkyl chain fluorinated acids permitted intramolecular proton transfer to be observed and macrocyclic conformational control to be achieved. Furthermore, acid-porphyrin complexation is shown to be compatible with established metal-ligand interactions in the generation of novel supramolecular assemblies in solution.

A distinctive strain of tobacco necrosis virus (TNV) of unknown source was repeatedly isolated from water of the River Avon (Warwickshire) and two of its tributaries (R. Swift and R. Alne) using a technique developed for the concentration and isolation of water-borne bacteriophages. The same strain was isolated from the rivers Cam and Thames and from Lake Esthwaite (Cumbria) together with tomato bushy stunt virus.The TNV strain, designated Chenopodium necrosis (TNV-CN) was mechanically transmissible to C. amaranticolor and C. quinoa in both of which it caused local lesions and systemic infection. TNV-CN caused no infection when inoculated to tobacco (Nicotiana tabacum cv. White Burley) plants.The virus was not adsorbed to soil, could be isolated from leachate of soil in which systemically infected C. quinoa were grown and C. quinoa plants became infected when grown in soil watered with suspensions of the virus.The virus was not transmitted by Myzus persicae but was vectored by the zoospores of a lettuce isolate of Olpidium brassicae.TNV-CN was infective after 10 min at 85 "C, 3 wk at 20 OC and when diluted to lov8 but not Purified virus preparations contained c. 26 nm isometric virus particles.TNV-CN contained single-stranded RNA (mol. wt 1.5 x lo6) and one protein (mol. wt c. 26-4 x lo3) which co-electrophoresed in polyacrylamide gels with the protein of the D strain of TNV (TNV-D). Analytical centrifugation of TNV-CN indicated a single component virus with the same sedimentation coefficient = 115s) and buoyant density (1.385) in a CsCl gradient as those of TNV-D.TNV-CN and TNV-D were indistinguishable serologically.

In this paper, we employ a VAR analysis to examine the nexus between military spending and economic growth in Sri Lanka which, due to the civil war there, has witnessed a significant increase in military spending over the last three decades while also recording healthy economic growth. The study finds that, compared with non-military spending, military spending exerts only a minimal positive impact on real GDP. Over a 10-year period, a 1% increase in non-military spending increases GDP by 1.6%. In contrast, military spending only increases GDP by 0.05%, suggesting that the economic benefits for Sri Lanka from a sustained peace may be considerable.Military spending, Sri Lanka, Economic growth, VAR analysis,

No abstract