NQR/NMR and Mössbauer spectroscopy of sulfides: Potential and versatility

Nuclear quadrupole resonance (NQR), nuclear magnetic resonance (NMR) and nuclear gamma-resonance (NGR or Mössbauer Effect) methods are generally described as highly sensitive tools in studies of local electronic structure and symmetry in solid-state materials. This is due to high informativity in electronic structure investigations, high resolution in phase-structural diagnostics (down to nano-scale), possibility to study polycrystalline and complex compounds, and to the non-destructive character of these methods. As applied to Earth sciences, both NQR/NMR and Mössbauer spectroscopy methods contribute to mineralogical material science and mineral physics. Another important aspect is the fact that these methods, as demonstrated recently, belong to unique techniques suitable for on-line bulk mineralogical analysis. This includes remotely operated sensors used with conveyor systems in mining/materials handling and similar applications where real-time data collection/processing provides significant commercial benefits. These developments open new pathways for NQR/NMR and Mössbauer spectroscopy applications. Notably, NQR/NMR and Mössbauer effects are observed primarily on different nuclei-probes but provide similar information about the local properties of materials (hyperfine fields, electric field gradients and relaxation effects). This makes NQR/NMR and Mössbauer methods mutually complementary despite their significant technical differences. This paper includes examples of recent applications of NQR, NMR and Mössbauer spectroscopic tools to studies of copper-, antimony- and iron-containing sulfides, demonstrating how these methods can contribute to an improved understanding of geochemical problems. © 2013 E. Schweizerbart'sche Verlagsbuchhandlung, D-70176 Stuttgart

Phase transition and anomalous electronic behavior in layered dichalcogenide CuS (covellite) probed by NQR

Nuclear quadrupole resonance (NQR) on copper nuclei has been applied for studies of the electronic properties of quasi-two-dimensional low-temperature superconductor CuS (covellite) in the temperature region between 1.47 and 290 K. Two NQR signals corresponding to two non-equivalent sites of copper in the structure, Cu(1) and Cu(2), has been found. The temperature dependences of copper quadrupole frequencies, line-widths and spin-lattice relaxation rates, which so far had never been investigated so precisely for this material, altogether demonstrate the structural phase transition near 55 K, which accompanies transformations of electronic spectrum not typical for simple metals. The analysis of NQR results and their comparison with literature data show that the valence of copper ions at both sites is intermediate in character between monovalent and divalent states with the dominant of the former. It has been found that there is a strong hybridization of Cu(1) and Cu(2) conduction bands at low temperatures, indicating that the charge delocalization between these ions takes place even in 2D regime. Based on our data, the occurrence of energy gap, charge fluctuations and charge-density waves, as well as the nature of phase transition in CuS are discussed. It is concluded that some physical properties of CuS are similar to those of high-temperature superconductors (HTSC) in normal state.Comment: to be publishe

Geochemistry of abyssal peridotites (Mid-Atlantic Ridge, 15°20′N, ODP Leg 209) : implications for fluid/rock interaction in slow spreading environments

Author Posting. © Elsevier B.V., 2006. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Chemical Geology 234 (2006): 179-210, doi:10.1016/j.chemgeo.2006.04.011.Abyssal peridotite from the 15°20’N area of the Mid-Atlantic Ridge show complex geochemical variations among the different sites drilled during ODP Leg 209. Major element compositions indicate variable degrees of melt depletion and refertilization as well as local hydrothermal metasomatism. Strongest evidence for melt-rock interactions are correlated Light Rare Earth Element (LREE) and High Field Strength Element (HFSE) additions at sites 1270 and 1271. In contrast, hydrothermal alteration at Sites 1274, 1272, and 1268 causes LREE mobility associated with minor HFSE variability, reflecting the low solubility of HFSE in aqueous solutions. Site 1274 contains the least-altered, highly refractory, peridotite with strong depletion in LREE and shows a gradual increase in the intensity of isochemical serpentinization; except for the addition of H2O which causes a mass gain of up to 20 g/100 g. The formation of magnetite is reflected in decreasing Fe2+/Fe3+ ratios. This style of alteration is referred to as rock-dominated serpentinization. In contrast, fluid-dominated serpentinization at Site 1268 is characterized by gains in sulfur and development of U-shaped REE pattern with strong positive Eu anomalies which are also characteristic for hot (350 to 400°C) vent-type fluids discharging from black smoker fields. Serpentinites at Site 1268 were overprinted by talc alteration under static conditions due to interaction with high aSiO2 fluids causing the development of smooth, LREE-enriched patterns with pronounced negative Eu anomalies. These results show that hydrothermal fluid-peridotite and fluid-serpentinite interaction processes are an important factor regarding the budget of exchange processes between the lithosphere and the hydrosphere in slow spreading environments.ODP is sponsored by the U.S. National Science Foundation (NSF) and participating countries under management of Joint Oceanographic Institutions (JOI), Inc

РОЛЬ ГЕНОВ RLM И AVRLM В РЕАЛИЗАЦИИ СПЕЦИФИЧЕСКОЙ УСТОЙЧИВОСТИ К ФОМОЗУ У РАПСА

As part of the study, DNA markers for local races L. maculans were identified and found that the AvrLm4-7 sequence in the selected fungus population is specifically recognized by the resistance Rlm4 and Rlm7 genes. The SCAR marker BN204 was identified, which allows us to identify homozygous and heterozygous plants carrying the Rlm4 gene. The work collection, including 22 varieties and 39 hybrids of rape, was analyzed using the DNA marker BN204. PCR results allowed us to establish that the number of individual plants with the resistance Rlm4 gene was higher than the number of stable forms characterized by the infection of leaf explants with pathogen races carrying the AvrLm4-7 sequence. It is supposed that these individual plants contain the Rlm4 gene, but they lack the Rlm7 gene.В ходе исследования выявлены ДНК-маркеры к местным расам L. maculans и установлено, что в популяции отобранного гриба присутствует последовательность AvrLm4-7, которая специфично распознается генами устойчивости Rlm4 и Rlm7. Выявлен SCAR-маркер BN204, позволяющий идентифицировать гомозиготные и гетерозиготные растения, несущие ген Rlm4. С использованием ДНК-маркера BN204 была проанализирована рабочая коллекция, включающая 22 сорта и 39 сортообразцов рапса. Результаты ПЦР позволили установить, что количество индивидуальных растений с геном устойчивости Rlm4 было выше, чем количество устойчивых форм, охарактеризованных путем заражения листовых эксплантов расами патогена, несущими последовательность AvrLm4-7. Предполагается, что данные индивидуальные растения содержат ген Rlm4, однако у них отсутствует ген Rlm7.

Business analytics in industry 4.0: a systematic review

Recently, the term “Industry 4.0” has emerged to characterize several Information Technology and Communication (ICT) adoptions in production processes (e.g., Internet-of-Things, implementation of digital production support information technologies). Business Analytics is often used within the Industry 4.0, thus incorporating its data intelligence (e.g., statistical analysis, predictive modelling, optimization) expert system component. In this paper, we perform a Systematic Literature Review (SLR) on the usage of Business Analytics within the Industry 4.0 concept, covering a selection of 169 papers obtained from six major scientific publication sources from 2010 to March 2020. The selected papers were first classified in three major types, namely, Practical Application, Reviews and Framework Proposal. Then, we analysed with more detail the practical application studies which were further divided into three main categories of the Gartner analytical maturity model, Descriptive Analytics, Predictive Analytics and Prescriptive Analytics. In particular, we characterized the distinct analytics studies in terms of the industry application and data context used, impact (in terms of their Technology Readiness Level) and selected data modelling method. Our SLR analysis provides a mapping of how data-based Industry 4.0 expert systems are currently used, disclosing also research gaps and future research opportunities.The work of P. Cortez was supported by FCT - Fundação para a Ciência e Tecnologia within the R&D Units Project Scope: UIDB/00319/2020. We would like to thank to the three anonymous reviewers for their helpful suggestions

Метафізика духовної впливовості Київської духовної академії (на прикладі сім'ї Булгакових)

Сiм’я Булгакових суттєво вплинула на розвиток свiтової культури, вона являється частиною культурної спадщини Києва i новi знання про творчiсть представникiв цiєї сiм’ї являють собою величезний iсторичний та науковий iнтерес, а також доповнюють нашi знан- ня про епоху релiгiйно-фiлософського ренесансу кiнця ХIХ - початку ХХ столiття. Великий вплив на формування свiтогляду Афанасiя Iвановича Булгакова (батька Михайла Булгакова) i Миколи Iвановича Булгакова (дядька знаменитого письменника) мала Київська духовна академiя. У данiй публiкацiї особлива увага придiляється дослiдженню маловивченої бiографiї Миколи Iвановича Булгакова, випускника КДА, викладача Тифлiської православної семiнарiї, в якiй навчався Йосип Сталiн. Подiї, якi вiдбулися в цiй семiнарiї та роль в цих подiях М. I. Булгакова, знайшли своє вiдображення в останнiй  п’єсi Михайла Булгакова «Батум»