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Artigo Revisado por pares

Leonid E. Popov, Lars E. Holmer,

... from Scandinavia, Kazakhstan, and South Ural Mountains LEONID POPOV, LEONID POPOVSearch for more papers by this authorLARS E. ... HOLMERSearch for more papers by this author LEONID POPOV, LEONID POPOVSearch for more papers by this authorLARS E. ...

Tópico(s): Geological Formations and Processes Exploration

1994 - Wiley | Lethaia

Artigo Acesso aberto Revisado por pares

Leonid E. Popov, Michael G. Bassett, Lars E. Holmer, Christian B. Skovsted, Michael Zuykov,

... Palaeozoic Craniiformea: implications for brachiopod phylogeny LEONID E. POPOV, LEONID E. POPOVSearch for more papers by this authorMICHAEL ... for more papers by this author LEONID E. POPOV, LEONID E. POPOVSearch for more papers by this authorMICHAEL ... 1111/j.1502-3931.2009.00197.xCitations: 8 Leonid E. Popov, [[email protected]] and Michael G. Bassett, [[email protected]], ...

Tópico(s): Paleontology and Evolutionary Biology

2009 - Wiley | Lethaia

Artigo Revisado por pares

Michael G. Bassett, Lars E. Holmer, Leonid E. Popov, John R. Laurie,

... SwedenSearch for more papers by this authorLEONID E. POPOV, LEONID E. POPOV All-Russia Geological Research Institute (VSEGEI), ... SwedenSearch for more papers by this authorLEONID E. POPOV, LEONID E. POPOV All-Russia Geological Research Institute (VSEGEI), Srednii prospekt ...

Tópico(s): Paleontology and Evolutionary Biology

1993 - Wiley | Lethaia

Artigo Revisado por pares

Mohammad Ghavidel‐Syooki, David H. Evans, Mansoureh Ghobadi Pour, Leonid E. Popov, J. Javier Álvaro, Utkyr Rakhmonov, Inna A. Klishevich, Mohammad H. Ehsani,

... of Sciences, Golestan University, Gorgan, Iran; Leonid E. Popov [leonid.popov@museumwales.ac.uk], Department of Geology, National Museum ...

Tópico(s): Geology and Paleoclimatology Research

2015 - Taylor & Francis | Alcheringa An Australasian Journal of Palaeontology

Artigo Revisado por pares

Leonid E. Popov, Robin Cocks,

... areas.Leonid E. Popov [lepbarry@yahoo.co.uk; leonid.popov@museumwales.ac.uk] Department of Geology, National Museum ...

Tópico(s): Marine Biology and Ecology Research

2013 - Taylor & Francis | Alcheringa An Australasian Journal of Palaeontology

Artigo Revisado por pares

V. A. Popov, Leonid A. Pautov, Е. Соколова, F. C. Hawthorne, C. McCammon, L. F. Bazhenova,

Polyakovite-(Ce), ideally REE 4 Mg Cr3+2 Ti2 Si4 O22, monoclinic, a 13.398(1), b 5.6974(5), c 11.042(1) A, β 100.539(2)°, V 828.6(2) A3, a:b:c = 2.3516:1:1.9381, space group C 2/ m , Z = 2, is a new mineral species from the Ilmen Mountains, southern Urals, Russia. It is of hydrothermal origin; associated minerals are calcite, dolomite, fluororichterite, phlogopite, forsterite, monazite-(Ce), clinohumite, chromite and davidite-(Ce). It occurs as irregular grains up to 3 cm in diameter and euhedral crystals ...

Tópico(s): Advanced Condensed Matter Physics

2001 - Mineralogical Association of Canada | The Canadian Mineralogist

Artigo Revisado por pares

Marjan Popov, Leonid Grčev, Hans Kr. Høidalen, Bjørn Gustavsen, Vladimir Terzija,

A large number of electromagnetic transient studies have so far reported findings related to the overvoltage behavior of systems within a broad frequency range. However, in most cases, actual grounding effects have been either not taken into account or have been just partially considered. Although an accurate methodology to study grounding effects exists, a detailed analysis of the grounding effects has not yet been fully performed. Moreover, many test applications are performed in laboratories ...

Tópico(s): Thermal Analysis in Power Transmission

2015 - Institute of Electrical and Electronics Engineers | IEEE Transactions on Industry Applications

Artigo Revisado por pares

D. D. Mysyk, Igor F. Perepichka, Dmitrii F. Perepichka, Martin R. Bryce, A. F. Popov, Leonid M. Goldenberg, Adrian J. Moore,

The synthesis and physical properties of four series of novel fluorene push−pull compounds (4−7) of the D−π−A type with intramolecular charge transfer (from 1,3- and 1,2-dithiole and 1,3-selenathiole donor (D) moieties) are described. The nature of the heteroatom (S or Se) in the donor fragment has no effect on the maxima of intramolecular absorption bands (λICT), whereas a change of position of the heteroatoms in the dithiole moiety from 1,3 to 1,2 leads to a substantial bathochromic shift in λICT. ...

Tópico(s): Photochemistry and Electron Transfer Studies

1999 - American Chemical Society | The Journal of Organic Chemistry

Artigo Revisado por pares

Leonid E. Popov, Mansoureh Ghobadi Pour, Mehri Hosseini,

... University) for constructive critical comments on the manuscript. Leonid Popov acknowledges support from the National Museum of Wales. ...

Tópico(s): Marine Biology and Ecology Research

2008 - Taylor & Francis | Alcheringa An Australasian Journal of Palaeontology

Artigo Revisado por pares

Sergey V. Popov, Leonid Margolis,

ABSTRACT Cell outgrowth formation by a force applied to the external membrane was investigated. This extrinsic force, which is generated in a special chamber by an alternating current (AC) electric field (EF) of high frequency, pulls the membrane outwards. The force arises due to the redistribution of ions beneath the cell surface and is applied to the thin (10–20 Å) undermembrane layer. This force is sufficient to generate cell-specific membrane protrusions of various types. The morphology of these ...

Tópico(s): 3D Printing in Biomedical Research

1988 - The Company of Biologists | Journal of Cell Science

Artigo Revisado por pares

Elizaveta A. Beletskaya, Ekaterina A. Lukina, Mikhail N. Uvarov, Alexander A. Popov, Leonid V. Kulik,

The key process in organic solar cell operation is charge separation under light illumination. Due to the low dielectric constant of organic materials, the Coulomb attraction energy within the interfacial charge-transfer state (CTS) is larger than the thermal energy. Understanding the mechanism of charge separation at the organic donor/acceptor interface still remains a challenge and requires knowledge of the CTS temporal evolution. To address this problem, the CTS in the benchmark photovoltaic blend ...

Tópico(s): Organic Light-Emitting Diodes Research

2020 - American Institute of Physics | The Journal of Chemical Physics

Artigo Revisado por pares

Adam S. Smith, Roger Benson,

... исследования для того, чтобы восстановить эволюцию ранних плезиозаврид. [Leonid Popov].

Tópico(s): Evolution and Paleontology Studies

2014 - Taylor & Francis | Monographs of the Palaeontographical Society

Artigo Revisado por pares

Mohibullah Mohibullah, Mark Williams, Jan Zalasiewicz,

... и роды, известные также и на Авалонском палеоконтиненте. [Leonid Popov].

Tópico(s): Geological Studies and Exploration

2013 - Taylor & Francis | Monographs of the Palaeontographical Society

Artigo Revisado por pares

Timothy P. Topper, David A. T. Harper, Per Ahlberg,

... herring. The manuscript benefited from constructive reviews of Leonid Popov and Michael Streng.

Tópico(s): Geochemistry and Elemental Analysis

2013 - Taylor & Francis | GFF

Artigo Acesso aberto Revisado por pares

Tatiana Ju. Tolmacheva, К. Е. Degtyarev, Joakim Samuelsson, Lars E. Holmer,

... authors gratefully acknowledge both reviewers Ian Percival and Leonid Popov for many constructive and helpful suggestions.

Tópico(s): Evolution and Paleontology Studies

2008 - Taylor & Francis | Alcheringa An Australasian Journal of Palaeontology

Artigo Acesso aberto Revisado por pares

Marjan Popov, Leonid Grčev, L. vanderSluis, Vladimir Terzija,

Ferromagnetic materials, such as steel, are used for shielding of power and telecommunication cables. These shields often provide path for currents during faults or lightning and are important for the integrity and safety of electrical systems and devices. Since such currents might be with low- or high-frequency content, and of low or high intensity, ferromagnetic shield behavior might be quite different due to hysteresis. This paper describes a method for analyzing the dynamic behavior of ferromagnetic ...

Tópico(s): Lightning and Electromagnetic Phenomena

2005 - Institute of Electrical and Electronics Engineers | IEEE Transactions on Power Delivery

Artigo

Lars E. Holmer, Leonid E. Popov,

Abstract Ceratreta tanneri is a widespread and biostratigraphically significant species within Baltoscandia. In northern Estonia and the Leningrad district (USSR) it is restricted to the Upper Cambrian quartzose Ülgase and Ladoga formations (lower Westergaardodina Biozone). In Sweden it has been found in the Upper Cambrian alum shales in Östergötland, where it is associated with trilobites of the Leptoplastus to lower Peltura biozones; in the Siljan district (Dalarna) the species has been isolated ...

Tópico(s): Geological formations and processes

1990 - Taylor & Francis | Geologiska Foereningan i Stockholm Foerhandlingar

Artigo Revisado por pares

Wladimir Ju. Gorjansky, Leonid E. Popov,

Available data on the anatomy, ontogeny embryology of Brachiopoda (sensu lato) suggest that this Phylum in the traditional view is in fact a clade of organization includes two stocks of lophophorate organisms of quite different origins. Their rank does not correspond to existing Class divisions. The phosphatic-shelled in articulates are regarded as a separate Class Lingulata. The Phylum Brachiopoda (sensu stricto) is restricted to the calcareous-shelled inarticulate articulate lineages. Ancestors ...

Tópico(s): Aquatic Invertebrate Ecology and Behavior

1986 - Wiley | Lethaia

Artigo Revisado por pares

Michael G. Bassett, Leonid E. Popov, Richard J. Aldridge, Sarah E. Gabbott, Johannes N. Theron,

Within the Soom Shale Lagerstätte of South Africa (Upper Ordovician, Hirnantian), two brachiopod taxa preserve traces of organic tissue. In Trematis , presumed bands of periostracum are preserved on the flanks of the pedicle notch, and clay mineral casts of the pedicle are preserved in many specimens of Kosoidea. Both these genera are organophosphatic-shelled Linguliformea, together with a third genus identified as Plectoglossa . A fourth brachiopod taxon in the fauna belongs within the calcitic-shelled ...

Tópico(s): Marine and environmental studies

2009 - Cambridge University Press | Journal of Paleontology

Artigo Acesso aberto Revisado por pares

Mansoureh Ghobadi Pour, Leonid E. Popov,

In the Derenjal Mountains of east Central Iran, the upper part of the Shirgesht Formation (uppermost Darriwilian) contains a distinct trilobite assemblage that includes Neseuretinus birmanicus and Ovalocephalus aff.obsoletus among others.Both genera were previously unknown in Iran.The occurrence of Ovalocephalus represents the earliest sign of westward taxon migration from China towards higher latitudes along the West Gondwanan margin, which may be related to global warming, after a short episode ...

Tópico(s): Geological and Geochemical Analysis

2009 - Institute of Paleobiology | Acta Palaeontologica Polonica

Artigo Revisado por pares

Leonid E. Popov, Michael G. Bassett, Lars E. Holmer, Mansoureh Ghobadi Pour,

New Late Cambrian (Furongian) to Early Ordovician (Tremadocian) assemblages of micromorphic organo-phosphatic (linguliformean) brachiopods from Iran are characterised by the presence of exceptionally well preserved material of the Order Siphonotretida, a small, phylogenetically important group with a very poorly documented Cambrian history. Unlike other known Cambrian siphonotretides, which generally lack true spines, the new Iranian taxa preserve the constant presence of hollow spines from as early ...

Tópico(s): Protist diversity and phylogeny

2009 - Elsevier BV | Gondwana Research

Artigo Revisado por pares

Leonid E. Popov, Michael G. Bassett, Vyacheslav G. Zhemchuzhnikov, Lars E. Holmer, Inna A. Klishevich,

Abstract Two separate tectonic blocks in the southwestern segment of the Kazakhstanian orogen, the Chu–Ili terrane and the Karatau–Naryn terrane (with particular attention to Malyi Karatau), are selected to illustrate their geological history and major biogeographical signatures from the Cambrian to the early Silurian. Mid- to Late Ordovician brachiopod and trilobite faunas of Chu–Ili show increased endemicity of shallow shelf assemblages, whereas distinct links to equatorial (‘east’) peri-Gondwanan ...

Tópico(s): Geochemistry and Geologic Mapping

2009 - Geological Society of London | Geological Society London Special Publications

Artigo Revisado por pares

Sergey V. Popov, T SVITKINA, Leonid Margolis, Tian Yow Tsong,

Tópico(s): Microbial Inactivation Methods

1991 - Elsevier BV | Biochimica et Biophysica Acta (BBA) - Biomembranes

Capítulo de livro Revisado por pares

Leonid E. Popov,

Traditionally, Brachiopoda (sensu lato) is regarded as a distinct phylum of lophophorate animals and is divided into two major taxa, Class Inarticulata (or Ecardines) and Class Articulata (or Testicardines). Both taxa are polythetic, but their diagnoses are based mainly on two features: the presence or absence of the articulation of the valves, and an open or blind digestive tract. The known differences between classes are possibly persistent from the beginning of the Ordovician. However, the earliest ...

Tópico(s): Astro and Planetary Science

1992 - Springer Nature | Topics in geobiology

Artigo Revisado por pares

Leonid E. Popov, Lars E. Holmer, James F. Miller,

Seven genera and eight species of lingulate brachiopods are described from the Cambrian-Ordovician boundary beds (Cambrooistodus minutus Conodont Subzone to Rossodus manitouensis Conodont Zone) at the Lawson Cove and Lava Dam North sections, Ibex area, Utah, USA. The fauna includes one new linguloid genus, Wahwahlingula, and four new species, Lingulella? incurvata, Zhanatella utahensis, Conotreta millardensis, and Quadrisonia? lavadamensis. Lingulate brachiopods from this interval are very poorly ...

Tópico(s): Marine Biology and Ecology Research

2002 - Cambridge University Press | Journal of Paleontology

Artigo Acesso aberto

Leonid E. Popov, L. R. M. Cocks, Igor F. Nikitin,

Synopsis 13Introduction 13Outline of geology and fossil localities 14Faunal Associations 22Overall palaeoecology 26Systematic palaeontology 27Linguloidea 28Discinoidea 28Siphonotretoidea 30Craniopsoidea 30Strophomenoidea 30Plectambonitoidea 38Chilidiopsoidea 53Triplesioidea 53Protorthoidea 58Orthoidea 58Plectorthoidea 61Enteletoidea 64Camarelloidea 64Rhynchotrematoidea 74Lissatrypoidea 76Meristelloidea 76Acknowledgments 77References 77The brachiopod fauna from the Anderken Formation (Lower to Middle ...

Tópico(s): Geology and Paleoclimatology Research

2002 - Cambridge University Press | Bulletin of the Natural History Museum Geology Series

Artigo Revisado por pares

Michael G. Bassett, Leonid E. Popov, Lars E. Holmer,

Abstract Brachiopod-dominated palaeocommunities incorporating a structure typical of faunal groups within the Palaeozoic Evolutionary Fauna were already present in North and East Gondwana and associated terranes as early as the mid-Cambrian, confined exclusively to shallow marine, inshore environments. The late Cambrian and Tremadoc record of these faunas is incomplete, because of pronounced global sea-level lowstand and subsequent break-up and destruction of the Cambrian Gondwanan margin. It is ...

Tópico(s): Geochemistry and Elemental Analysis

2002 - Geological Society of London | Geological Society London Special Publications

Artigo Revisado por pares

Taniel Danelian, Leonid E. Popov,

Abstract Since the 1970s Ordovician carbonate rocks from Kazakhstan have provided well-preserved radiolarian faunas and this country remains one of the most important areas in the world to learn about Lower Palaeozoic radiolarian taxonomy and biostratigraphy. Here we describe a new lower Arenigian radiolarian assemblage and discuss all currently available Ordovician radiolarian data from Kazakhstan. The newly discovered assemblage is curiously oligospecific, despite its good state of preservation. ...

Tópico(s): Methane Hydrates and Related Phenomena

2003 - EDP Sciences | BSGF – Earth Sciences Bulletin

Artigo Revisado por pares

Igor F. Nikitin, Leonid E. Popov, Michael G. Bassett,

A medium−diversity fauna of late Ordovician rhynchonelliformean brachiopods occurs in the Tauken Formation (upper Caradoc–lowermost Ashgill) of north Central Kazakhstan. It demonstrates close similarity to the approximately contem− poraneous faunas characteristic of shallow clastic shelves (BA 2–3) of the Chingiz and Chu−Ili ranges (both in Kazakhstan) and South China, but is characterized by a high proportion of endemic new species, including Tetra− phalerella bestiubensis sp. nov., Glyptomena kaskolica ...

Tópico(s): Geochemistry and Elemental Analysis

2003 - Institute of Paleobiology | Acta Palaeontologica Polonica

Artigo Revisado por pares

Lars E. Holmer, Leonid E. Popov,

The poorly known type species of Acrotreta, A. subconica Kutorga, 1848 [= Spondylotreta faceta Gorjansky, 1969], is redescribed and a neotype selected from the lower Arenig (Billingen Stage, Oeland Series) Päite beds in the environs of St. Petersburg (Tosna river), Russia. Acrotreta is also the type of the lingulate brachiopod family Acrotretidae Schuchert, 1893, and order Acrotretida Kuhn, 1949. Four new species are described: A. korynevskii from the upper Tremadoc–lower Arenig, South Ural Mountains; ...

Tópico(s): Geological Studies and Exploration

1994 - Cambridge University Press | Journal of Paleontology