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The adsorption of thiophene and 2,2′-bithiophene on Ag(111) was studied using temperature programmed desorption and near-edge X-ray-absorption fine-structure (NEXAFS). The assignment of the NEXAFS resonances is supported by Xα scattered-wave calculations. For thiophene we identify a compressed and a relaxed monolayer species. Whereas the molecules in the latter state are adsorbed parallel to the s

We report on C 1s and N 1s near-edge X-ray absorption (NEXAFS) investigations of highly oriented ultrathin films of 2,5-dimethyl-N,N′-dicyanoquinonediimine (DMe-DCNQI), tetracyano-quinonedimethane (TCNQ), and 2,5-dimethyl-1,4-benzoquinone (DMe-BQ) adsorbed on Ag(111). Several sharp resonances are resolved in the spectra indicating the localized electronic structure of these quinoide molecules. The

DMe-DCNQI forms highly-ordered ultrathin films on various single crystal surfaces. NEXAFS reveals flat lying molecules for all investigated film thicknesses (up to 40 layers) on nearly all substrates under investigation (Ag(111), Ag(100), Cu(100), Cu(111)). The C1s and N1s NEXAFS spectra of these condensed layers show several very sharp resonances. The comparison with the quinoide molecules TCNQ a

A workshop entitled "Stem Cells, Cell Therapies and Bioengineering in Lung Biology and Diseases" was hosted by the University of Vermont Larner College of Medicine in collaboration with the National Heart, Lung and Blood Institute, the Alpha-1 Foundation, the Cystic Fibrosis Foundation, the International Society for Cell and Gene Therapy and the Pulmonary Fibrosis Foundation. The event was held fr

Interesting optical properties are obtained if highly ordered interfaces and thin films of large organic molecules are prepared on an atomically flat and clean substrate. Then the optical spectra are very different from those of conventional films and reveal a variety of finestructures. On the basis of one example, quaterthiophene on Ag(111), it is demonstrated that long-range ordered monolayers w

On the basis of the example of quaterthiophene (4T) on a Ag(111) surface, we demonstrate that epitaxial thin films can be prepared on a single crystalline substrate under suitable conditions. Optical spectra of such 4T films exhibit a highly resolved fine structure similar to that of isolated molecules. The detailed spectroscopic information thus obtained yields new insight into questions such as

Thin films (less than 40 Å) of quaterthiophene (4T) were vapour deposited onto a Ag(111) surface under ultrahigh vacuum (UHV) and were investigated concerning their geometrical structure and photoluminescence (PL) properties by low-energy electron diffraction (LEED) and optical spectroscopy, respectively. Two different structural phases (α and β) were observed, which exhibit high structural order,

Ultrathin layers of 2,5-dimethyl-N,N′-dicyanoquinonediimine (DMe-DCNQI) have been grown on a Ag (111) surface by vapour deposition in ultrahigh vacuum. The films have been characterized by near-edge X-ray absorption fine structure (NEXAFS), low-energy electron diffraction (LEED), Thermal desorption measurements and X-ray photoelectron spectroscopy to study orientation, lateral order, interface bon

A monolayer of N2O/Ni(111), a submonolayer species, and a monolayer of N2O/Ni\(111\)+O p[2×2] were studied using near-edge x-ray absorption fine-structure spectroscopy. From the polarization dependence we derive bent N2O molecules for the monolayer species whereas the two other species remain linear upon adsorption. Using the Xα-scattered-wave method the polarization dependence of the three π* res

The orientation of molecular (Formula presented)O in a bilayer on defect-free NaCl(100) and of chemisorbed OH adsorbed at F centers on the (100) surface of NaCl was investigated using angle-resolved O K edge near-edge x-ray-absorption fine-structure spectroscopy (NEXAFS). High-quality single crystalline thin films of NaCl(100) of about four monolayers thickness were grown on Ge(100). These films w

The armed conflict shaped and determined land-uses, water access and social and environmental norms in highlands regions in Colombia for several decades. The withdrawal of the Revolutionary Armed Forces of Colombia (FARC) after the Peace Agreement with the government of Colombia in 2016, has brought new dynamics in access and uses of land leading to increasingly visible social-environmental impact

The Amazon rainforests and their biological diversity are being lost rapidly by the onslaught of extractive industries, large-scale agriculture and infrastructure development, which also undermines the integrity of indigenous territories and ethnicities, threatening the tremendous cultural diversity of the Amazon. The loss of forest, the disintegration of local communities and the increase of the

Planet formation processes or evolution mechanisms are surmised to be at the origin of the hot Neptune desert. Studying exoplanets currently living within or at the edge of this desert could allow disentangling the respective roles of formation and evolution. We present the High Accuracy Radial velocity Planet Searcher (HARPS) transmission spectrum of the bloated super-Neptune WASP-166b, located a

Introduction Osteoarthritis (OA) of the first carpometacarpal (CMC-1) joint is a common hand disorder with symptoms including pain and weakness of the thumb. Previous studies have associated high BMI with OA of weight-bearing joints, whereas studies regarding non-weight-bearing joints have shown conflicting results. Thus, the aim of this study was to investigate the influence of overweight and obe

Rapporten analyserar inkomstskillnader mellan land och stad för perioden 1990-2017. Vi börjar med att rangordna hela Sverige utifrån en land-stad dimension. Rangordningen delar in befolkningen i olika grupper där befolkningen i de mest glesa områdena i Sverige och befolkningen i de mest urbana områdena utgör ytterligheterna. Med hjälp av rangordningen undersöker vi sedan inkomster i de olika grupp

The dynamical stability of tightly packed exoplanetary systems remains poorly understood. While a sharp stability boundary exists for a two-planet system, numerical simulations of three-planet systems and higher show that they can experience instability on timescales up to billions of years. Moreover, an exponential trend between the planet orbital separation measured in units of Hill radii and th

Background The obesity epidemic has influenced pain rehabilitation clinics. To date, little is known about baseline level of physical activity (PA) in patients referred to pain rehabilitation clinics. We aimed to investigate the PA levels of patients referred to pain rehabilitation clinics and to evaluate the effect of excess weight on PA level. Methods and findings Data were obtained from the Swe