19 research outputs found

    COMPLEXATION IN THE SYSTEM ZINC (II)-CHROME (III)-NICKEL (II)-GLYCINE-WATER

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    The relevance of studying complexation in the system under consideration is associated with the development of the role of heteronuclearcompounds in the processes of electrochemical production of alloys. According to the known concepts, in heteronuclear compounds, the more electronegative atom makes a greater contribution to the bonding orbital, and the orbital of the less electronegative atom, to the antibonding one. This contributes to the convergence of the reduction potentials of metal ions present in such a compound and the production of an electrochemical alloy. In addition, it is known that an increase in the effective radius of complex ions, which is characteristic of heteronuclear compounds, decreases the activation energy of their electrochemical reduction. The aim of this work is to obtain data on complexation in the system Zn (II)-Cr (III)-Ni (II)-glycine-water, composition and stability of heteronuclear compounds. The establishment of the composition of the complexes formed in the system under study was preceded by the acquisition of data on the complexation of each of the indicated elements in individual solutions. It was previously established that in the Zn(II)-Cr (III)-glycine-water system in the pH range 1.0-3.5, heteronuclear forms [CrZn(HGly)4Gly4]+ and [CrZn(HGly)2Gly6]− prevail, at pH 2.2 - 4.0, the share of [CrZnGly8]3− accumulation increases. To establish the composition of the resulting complexes, we used pH metric titration and the method of nuclear magnetic relaxation (NMR) of protons in combination with mathematical processing of the results (CPESSP program). The formation of heteronuclear complexes [CrNiZn(HGly)4Gly4]3+, [CrNiZn(HGly)2Gly6]+ was established, their formation constants and the fraction of accumulation (HGly - glycine) were calculated. The results of the work were used in the development of electrolytes for the process of electrochemical alloying of zinc coatings simultaneously with chromium and nickel

    GRANDMA Observations of ZTF/Fink Transients during Summer 2021

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    We present our follow-up observations with GRANDMA of transient sources revealed by the Zwicky Transient Facility (ZTF). Over a period of six months, all ZTF triggers were examined in real time by a dedicated science module implemented in the Fink broker, which will be used for the data processing of the Vera C. Rubin Observatory. In this article, we present three selection methods to identify kilonova candidates. Out of more than 35 million candidates, a hundred sources have passed our selection criteria. Six were then followed-up by GRANDMA (by both professional and amateur astronomers). The majority were finally classified either as asteroids or as supernovae events. We mobilized 37 telescopes, bringing together a large sample of images, taken under various conditions and quality. To complement the orphan kilonova candidates (those without associated gamma-ray bursts, which were all), we included three additional supernovae alerts to conduct further observations of during summer 2021. We demonstrate the importance of the amateur astronomer community that contributed images for scientific analyzes of new sources discovered in a magnitude range r'=17-19 mag. We based our rapid kilonova classification on the decay rate of the optical source that should exceed 0.3 mag/day. GRANDMA's follow-up determined the fading rate within 1.5+/-1.2 days post-discovery, without waiting for further observations from ZTF. No confirmed kilonovae were discovered during our observing campaign. This work will be continued in the coming months in the view of preparing for kilonova searches in the next gravitational-wave observing run O4

    GRANDMA Observations of ZTF/Fink Transients during Summer 2021

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    We present our follow-up observations with GRANDMA of transient sources revealed by the Zwicky Transient Facility (ZTF). Over a period of six months, all ZTF triggers were examined in real time by a dedicated science module implemented in the Fink broker, which will be used for the data processing of the Vera C. Rubin Observatory. In this article, we present three selection methods to identify kilonova candidates. Out of more than 35 million candidates, a hundred sources have passed our selection criteria. Six were then followed-up by GRANDMA (by both professional and amateur astronomers). The majority were finally classified either as asteroids or as supernovae events. We mobilized 37 telescopes, bringing together a large sample of images, taken under various conditions and quality. To complement the orphan kilonova candidates (those without associated gamma-ray bursts, which were all), we included three additional supernovae alerts to conduct further observations of during summer 2021. We demonstrate the importance of the amateur astronomer community that contributed images for scientific analyzes of new sources discovered in a magnitude range r'=17-19 mag. We based our rapid kilonova classification on the decay rate of the optical source that should exceed 0.3 mag/day. GRANDMA's follow-up determined the fading rate within 1.5+/-1.2 days post-discovery, without waiting for further observations from ZTF. No confirmed kilonovae were discovered during our observing campaign. This work will be continued in the coming months in the view of preparing for kilonova searches in the next gravitational-wave observing run O4

    GRANDMA Observations of ZTF/Fink Transients during Summer 2021

    No full text
    We present our follow-up observations with GRANDMA of transient sources revealed by the Zwicky Transient Facility (ZTF). Over a period of six months, all ZTF triggers were examined in real time by a dedicated science module implemented in the Fink broker, which will be used for the data processing of the Vera C. Rubin Observatory. In this article, we present three selection methods to identify kilonova candidates. Out of more than 35 million candidates, a hundred sources have passed our selection criteria. Six were then followed-up by GRANDMA (by both professional and amateur astronomers). The majority were finally classified either as asteroids or as supernovae events. We mobilized 37 telescopes, bringing together a large sample of images, taken under various conditions and quality. To complement the orphan kilonova candidates (those without associated gamma-ray bursts, which were all), we included three additional supernovae alerts to conduct further observations of during summer 2021. We demonstrate the importance of the amateur astronomer community that contributed images for scientific analyzes of new sources discovered in a magnitude range r'=17-19 mag. We based our rapid kilonova classification on the decay rate of the optical source that should exceed 0.3 mag/day. GRANDMA's follow-up determined the fading rate within 1.5+/-1.2 days post-discovery, without waiting for further observations from ZTF. No confirmed kilonovae were discovered during our observing campaign. This work will be continued in the coming months in the view of preparing for kilonova searches in the next gravitational-wave observing run O4

    GRANDMA observations of ZTF/Fink transients during summer 2021

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    International audienceWe present our follow-up observations with GRANDMA of transient sources revealed by the Zwicky Transient Facility (ZTF). Over a period of six months, all ZTF alerts were examined in real time by a dedicated science module implemented in the Fink broker, which will be used in filtering of transients discovered by the Vera C. Rubin Observatory. In this article, we present three selection methods to identify kilonova candidates. Out of more than 35 million alerts, a hundred sources have passed our selection criteria. Six were then followed-up by GRANDMA (by both professional and amateur astronomers). The majority were finally classified either as asteroids or as supernovae events. We mobilized 37 telescopes, bringing together a large sample of images, taken under various conditions and quality. To complement the orphan kilonova candidates, we included three additional supernovae alerts to conduct further observations during summer 2021. We demonstrate the importance of the amateur astronomer community that contributed images for scientific analyses of new sources discovered in a magnitude range râ€Č = 17 − 19 mag. We based our rapid kilonova classification on the decay rate of the optical source that should exceed 0.3 mag d^−1. GRANDMA’s follow-up determined the fading rate within 1.5 ± 1.2 d post-discovery, without waiting for further observations from ZTF. No confirmed kilonovae were discovered during our observing campaign. This work will be continued in the coming months in the view of preparing for kilonova searches in the next gravitational-wave observing run O4
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