eta and eta' mesons and dimension 2 gluon condensate <A^2>

The study of light pseudoscalar quark-antiquark bound states in the Dyson-Schwinger approach with the effective QCD coupling enhanced by the interplay of the dimension 2 gluon condensate and dimension 4 gluon condensate , is extended to the eta-eta' complex. We include the effects of the gluon axial anomaly into the Dyson-Schwinger approach to mesons. The calculated masses, mixing and two-photon decay widths of eta and eta' mesons are in agreement with experiment. Also, in a model-independent way, we give the modification of the Gell-Mann--Okubo and Schwinger nonet relations due to the interplay of the gluon anomaly and SU(3) flavor symmetry breaking.Comment: 15 pages, 2 tables, 1 eps figure, revtex

First Report of Peyronellaea lethalis Associated With Ascochyta Blight Complex of Field Pea in Serbia

Ascochyta blight complex is a significant and widespread disease of field pea (Pisum sativum L.) caused by Peyronellaea pinodes, P. pinodella, and Ascochyta pisi. During the 2015 growing season, screening of isolates revealed a previously unknown member of this complex. Thirteen single-conidial isolates were obtained using standard phytopathological protocols. To our knowledge, this is the first report of P. lethalis associated with Ascochyta blight complex of field pea in Serbia

Method of forming electronically conducting polymers on conducting and nonconducting substrates

The present invention provides electronically conducting polymer films formed from photosensitive formulations of pyrrole and an electron acceptor that have been selectively exposed to UV light, laser light, or electron beams. The formulations may include photoinitiators, flexibilizers, solvents and the like. These solutions can be used in applications including printed circuit boards and through-hole plating and enable direct metallization processes on non-conducting substrates. After forming the conductive polymer patterns, a printed wiring board can be formed by sensitizing the polymer with palladium and electrolytically depositing copper

Isolated oxygen defects in 3C- and 4H-SiC: A theoretical study

Ab initio calculations in the local-density approximation have been carried out in SiC to determine the possible configurations of the isolated oxygen impurity. Equilibrium geometry and occupation levels were calculated. Substitutional oxygen in 3C-SiC is a relatively shallow effective mass like double donor on the carbon site (O-C) and a hyperdeep double donor on the Si site (O-Si). In 4H-SiC O-C is still a double donor but with a more localized electron state. In 3C-SiC O-C is substantially more stable under any condition than O-Si or interstitial oxygen (O-i). In 4H-SiC O-C is also the most stable one except for heavy n-type doping. We propose that O-C is at the core of the electrically active oxygen-related defect family found by deep level transient spectroscopy in 4H-SiC. The consequences of the site preference of oxygen on the SiC/SiO2 interface are discussed

Supplementary material for the article: Jevtić, S.; Stefanović, A.; Stanković, D. M.; Pergal, M. V.; Ivanović, A. T.; Jokić, A.; Petković, B. B. Boron-Doped Diamond Electrode — A Prestigious Unmodified Carbon Electrode for Simple and Fast Determination of Bentazone in River Water Samples. Diamond and Related Materials 2018, 81, 133–137. https://doi.org/10.1016/j.diamond.2017.12.009

Supplementary material for: [https://doi.org/10.1016/j.diamond.2017.12.009]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2081]Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/3177

Supplementary material for the article: Jevtić, S.; Stefanović, A.; Stanković, D. M.; Pergal, M. V.; Ivanović, A. T.; Jokić, A.; Petković, B. B. Boron-Doped Diamond Electrode — A Prestigious Unmodified Carbon Electrode for Simple and Fast Determination of Bentazone in River Water Samples. Diamond and Related Materials 2018, 81, 133–137. https://doi.org/10.1016/j.diamond.2017.12.009

Supplementary material for: [https://doi.org/10.1016/j.diamond.2017.12.009]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2081]Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/3177

Effect of C∕Si ratio on deep levels in epitaxial 4H–SiC

Changing the ratio of carbon to silicon during the epitaxial 4H–SiC growth is expected to alter the dominant deep level trap, which has been attributed to a native defect. The C∕Si ratio was changed from one to six during epitaxialgrowth of SiC. Diodes fabricated on the epitaxial layer were then characterized using current-voltage and deep level transient spectroscopy. The single peak at 340K (Z1/Z2 peak), was deconvolved into two traps, closely spaced in energy. The concentration of one of the Z1/Z2 traps decreased with increasing C∕Si ratio. This result opposes theoretical predictions of carboninterstitial components, and supports assignment to a silicon antisite or carbonvacancy relationship. The concentration of the second component of the peak at 340K did not depend on the C∕Si ratio, which would indicate an impurity in an interstitial site

Evolution of ore-forming fluids in the Bukovik-Kadiica porphyry Cu deposit, Republic of Macedonia

The Bukovik-Kadiica mineralized system is hosted by Tertiary dacitic and andesitic volcanic rocks which have intruded the basement of Palaeozoic schists in the Serbo-Macedonian Massif of eastern Macedonia. The latest geological exploration has confirmed that this porphyry copper mineralizationis characterized by a dominance of chalcocite and covellite with associated chalcopyrite, emplectite, and bornite, with the highest grades in a zone of supergene enrichment. Silicification is the dominant alteration within the mineralized system, whilst zones of potassic, phyllic, argillic, propylitic, and advanced argillic alteration are also present. Silicification and sulphide mineralization are located in stockworks in altered dacite and andesite breccia. Dissolution of primary sulphides and chemical leaching are evident in the zones of oxidation, dominated by limonite breccia.The main copper mineralization has a vertical extent between 90 and 220 m. Fluid inclusion studies of mineralized quartz veins have identified three separate groups of fluids: saline inclusions which homogenize at 326-501 °C and have a salinity of 32-45 wt% NaCl equiv., vapour-dominated inclusions which homogenize at 438-497 °C and have a salinity of 6–16 wt% NaCl equiv., and more dilute, two-phase vapour–liquid inclusions that homogenize at 360-627 °C and have a salinity of 3-24 wt% NaCl equiv

Infrared renormalization of two-loop integrals and the chiral expansion of the nucleon mass

We describe details of the renormalization of two-loop integrals relevant to the calculation of the nucleon mass in the framework of manifestly Lorentz-invariant chiral perturbation theory using infrared renormalization. It is shown that the renormalization can be performed while preserving all relevant symmetries, in particular chiral symmetry, and that renormalized diagrams respect the standard power counting rules. As an application we calculate the chiral expansion of the nucleon mass to order O(q^6).Comment: Version accepted for publication in Nucl. Phys. A, missing one-loop diagram added, minor changes in notation, discussion of results improve

Application of Jain and Munczek's bound-state approach to gamma gamma-processes of pi0, eta_c and eta_b

We point out the problems affecting most quark--antiquark bound state approaches when they are faced with the electromagnetic processes dominated by Abelian axial anomaly. However, these problems are resolved in the consistently coupled Schwinger-Dyson and Bethe-Salpeter approach. Using one of the most successful variants of this approach, we find the dynamically dressed propagators of the light u and d quarks, as well as the heavy c and b quarks, and find the Bethe-Salpeter amplitudes for their bound states pi0, eta_c and \eta_b. Thanks to incorporating the dynamical chiral symmetry breaking, the pion simultaneously appears as the (pseudo)Goldstone boson. We give the theoretical predictions for the gamma-gamma decay widths of pi0, eta_c and eta_b, and for the pi0 gamma* -> gamma transition form factor, and compare them with experiment. In the chiral limit, the axial-anomaly result for pi0->gamma-gamma is reproduced analytically in the consistently coupled Schwinger-Dyson and Bethe-Salpeter approach, provided that the quark-photon vertex is dressed consistently with the quark propagator, so that the vector Ward-Takahashi identity of QED is obeyed. On the other hand, the present approach is also capable of quantitatively describing systems of heavy quarks, concretely eta_c and possibly eta_b, and their gamma-gamma decays. We discuss the reasons for the broad phenomenological success of the bound-state approach of Jain and Munczek.Comment: RevTeX, 37 pages, 7 eps figures, submitted to Int. J. Mod. Phys.