Iron-peak elements Sc, V, Mn, Cu and Zn in Galactic bulge globular clusters

Globular clusters are tracers of the history of star formation and chemical enrichment in the early Galaxy. Their abundance pattern can help understanding their chemical enrichment processes. In particular, the iron-peak elements have been relatively little studied so far in the Galactic bulge. The abundances of iron-peak elements are derived for the sample clusters, and compared with bulge field, and thick disk stars. We derive abundances of the iron-peak elements Sc, V, Mn, Cu, and Zn in individual stars of five bulge globular clusters (NGC 6528, NGC 6553, NGC 6522, NGC 6558, HP1), and of the reference thick disk/inner halo cluster 47 Tucanae (NGC 104). High resolution spectra were obtained with the UVES spectrograph at the Very Large Telescope over the years. The sample globular clusters studied span metallicities in the range -1.2<Fe/H]<0.0. V and Sc appear to vary in lockstep with Fe, indicating that they are produced in the same supernovae as Fe. We find that Mn is deficient in metal-poor stars, confirming that it is underproduced in massive stars; Mn-over-Fe steadily increases at the higher metallicities due to a metallicity-dependent enrichment by supernovae of type Ia. Cu behaves as a secondary element, indicating its production in a weak-s process in massive stars. Zn has an alpha-like behaviour at low metallicities, which can be explained in terms of nucleosynthesis in hypernovae. At the metal-rich end, Zn decreases with increasing metallicity, similarly to the alpha-elements.Comment: article resubmitted to Astronomy & Astrophysics, taking into account referee's comment

High-resolution abundance analysis of red giants in the metal-poor bulge globular cluster HP~1

The globular cluster HP~1 is projected at only 3.33 degrees from the Galactic center. Together with its distance, this makes it one of the most central globular clusters in the Milky Way. It has a blue horizontal branch (BHB) and a metallicity of [Fe/H]~-1.0. This means that it probably is one of the oldest objects in the Galaxy. Abundance ratios can reveal the nucleosynthesis pattern of the first stars as well as the early chemical enrichment and early formation of stellar populations. High-resolution spectra obtained for six stars were analyzed to derive the abundances of the light elements C, N, O, Na, and Al, the alpha-elements Mg, Si, Ca, and Ti, and the heavy elements Sr, Y , Zr, Ba, La, and Eu.} High-resolution spectra of six red giants that are confirmed members of the bulge globular cluster HP~1 were obtained with the 8m VLT UT2-Kueyen telescope with the UVES spectrograph in FLAMES-UVES configuration. The spectroscopic parameter derivation was based on the excitation and ionization equilibrium of FeI and FeII. We confirm a mean metallicity of [Fe/H] = -1.06~0.10, by adding the two stars that were previously analyzed in HP~1. The alpha-elements O and Mg are enhanced by about +0.3<[O,Mg/Fe]<+0.5 dex, Si is moderately enhanced with +0.15<[Si/Fe]<+0.35dex, while Ca and Ti show lower values of -0.04<[Ca,Ti/Fe]<+0.28dex. The r-element Eu is also enhanced with [Eu/Fe]~+0.4, which together with O and Mg is indicative of early enrichment by type II supernovae. Na and Al are low, but it is unclear if Na-O are anticorrelated. The heavy elements are moderately enhanced, with -0.20<[La/Fe]<+0.43dex and 0.0<[Ba/Fe]<+0.75~dex, which is compatible with r-process formation. The spread in Y, Zr, Ba, and La abundances, on the other hand, appears to be compatible with the spinstar scenario or other additional mechanisms such as the weak r-process.Comment: 15 pages, 8 figures In press in Astronomy & Astrophysics (2016

Synthesis and Complexing Properties of p-Toluensulfonylamido and Phosphorylamido Derivatives of Second-Generation Hyperbranched Polyester

© 2018, Pleiades Publishing, Ltd. Hyperbranched polyesters containing terminal p-toluenesulfonylamido and diethoxyphosphorylamido groups have been synthesized, and their complexes with copper(II) and cobalt(II) ions have been prepared. The thermal stability of the ligands and their metal complexes has been studied by differential scanning calorimetry

Creation of composite bronze-maraging steel alloy

The possibility is demonstrated of creating alloys based on the system Cu-Fe-Ni-Al, within which the matrix is bronze BrNA 4-1, "reinforced" with dendrites containing, apart from Fe and Cu, about 15% Ni and 1% Al. This dendrite composition provides dispersion hardening. Favorable dendrite morphology provides high deformability of these bronzes, and makes it possible to control mechanical and service properties by heat treatment over a wide range. © 2013 Springer Science+Business Media New York

High levels effects of vitamins A , D3 , E and C upon semen quality of bulls

Os efeitos de super dosagem de vitaminas A, D3, E e C sobre a qualidade do sêmen de 20 touros, 10 de origem europeia (Grupo I) e 10 de origem indiana (Grupo II), foram estudados visando a evitar seu declínio no período da seca. O experimento constou de três períodos: Preliminar, com duração de 6 semanas, Experimental (9 semanas) e Pós-experimental (9 semanas) com colheitas de sêmen semanais, utilizando-se vagina artificial para o Grupo I e eletroejaculação para o Grupo II. Durante todo o experimento os animais receberam 40.000 UI de vitamina A, 4.000 UI de vitamina D3 e 40mg de vitamina E contidos em 4kg de ração concentrada, por animal e por dia, além da forragem verde. No período experimental, cada animal recebeu, adicionalmente, 15ml de um complexo vitamínico A, D3 E C, que continha 50.000 UI de vitamina A, 5.000 UI de vitamina D3, 30mg de vitamina E e 1OOmg de vitamina C por ml. No total foram realizadas 480 colheitas de sêmen com seus respectivos espermogramas, analisando-se particularmente o volume de sêmen, motilidade, concentração espermática e formas patológicas, incluindo anormalidades do acrossomo, cabeça, inserção, peça intermediária, gotas citológicas, distais e presença de formas plasmáticas. Análise estatística aplicada aos resultados obtidos não foi capaz de revelar diferenças significativas, quanto à qualidade do sêmen, que se manteve praticamente inalterada antes, durante e depois da ministração do choque vitamínico. Esta ocorrência leva a supor que a suplementação de vitaminas A, D3 E e C para reprodutores bovinos no período da seca é desnecessária à produção de sêmen de boa qualidade, desde que os animais contém com teores adequados de vitaminas A, D3, E, na ração.  The purpose of this study was to determine the effect of high levels of vitamins A, D3, E and C upon semen quality of 20 bulls, 10 of European origin (group I) and 20 zebu bulls (group II) mainly during dry season. The trial had a 6 weeks preliminary step, an experimental period and a post-experimental period of 9 weeks each. Semen collections were made once a week, group I being collected with artificial vagina and group II by electroejaculation. Over 480 semen samples were collected from the 20 bulls. The animals were fed daily 4kg of a concentrate ration containing 40000 IU of vitamin A, 4000 IU of vitamin D3 and 40mg of vitamin E, besides grass. During the experimental period each animal received additionally “per os” 15ml of a vitamin A, D3,C complex, containing 50000 IU of vitamin A, 5000 IU of vitamin D3 , 30mg of vitamin E and 100mg of vitamin C per ml. Differences between periods were not significant regarding semen quality. It appears that the feeding of 15ml vitamin A D3, E, C Complex daily in addition to the normal ration did not increase the volume of semen produced by the bulls or the spermatozoa concentration in the semen, as so it did not improve the motility of the spermatozoa and did not change the per cent of abnormal spermatozoa

Development, characterization, and stability of O/W pepper nanoemulsions produced by high-pressure homogenization

Interest in the utilization of bioactive plant compounds in foods has increased due to their biochemical activities (antioxidant, antimicrobial, etc.), and as alternatives in the reduction of the use of high concentrations of chemical substances. However, some of these additives are hydrophobic, thus being harder to disperse into the food matrix, which is generally water-based. A good alternative is the use of low concentrations of these compounds as nanoemulsions. The objective of the present study was to develop oil-in-water nanoemulsions containing dedo-de-moça pepper extract for food applications. Research in the development of these nanoemulsions was carried out using a high-speed homogenizer, followed by a high-pressure homogenizer. The influence of the following parameters was assessed: type and concentration of surfactants, hidrophilic-lipophilic balance, lipid/aqueous phase ratio, surfactant/oil ratio, pepper extract composition in nanoemulsion, and processing conditions. Nanoemulsions were evaluated by environmental (centrifugal and thermal) and storage stabilities, characterized by average droplet size and -potential measurements, color, interfacial tension, atomic force, and cryo-scanning electron microscopy. Those with average droplet size between 132 ± 2.0 and 145 ± 1.0 nm were developed depending on working pressure and number of cycles; -potential was around 36.71 ± 0.62 mV and the best nanoemulsion was stable to centrifugation and most of the thermal stresses. Droplets were characterized with cryo-scanning electron microscopy as being spherical, homogeneous, and stable, and remained stable when stored at 4 °C and room temperature for over 120 days. The pepper nanoemulsion, developed in the present study, has potential applications in the food industry.The first author gratefully acknowledges the CNPq and CAPES (National Council for Scientific and Technological Development, Program Science without Boarder) for the BSWE^ PhD (Process 236877/2012-1) fellowship, and CAPES for the national PhD fellowship. The last author acknowledges the São Paulo Research Foundation (FAPESP) Brazil, for the grant (CEPID-FoRC, 2013/07914-8).info:eu-repo/semantics/publishedVersio