Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "shell microstructure" wg kryterium: Temat

  Lista filtrów
Wyrównaj
    Wyświetlanie 1-6 z 6
    Tytuł:
    New Barremian rhynchonellide brachiopod genus from Serbia and the shell microstructure of Tetrarhynchiidae
    Autorzy:
    Radulovic, B.
    Motchurova-Dekova, N.
    Radulovic, V.
    Powiązania:
    https://bibliotekanauki.pl/articles/20693.pdf
    Data publikacji:
    2007
    Wydawca:
    Polska Akademia Nauk. Instytut Paleobiologii PAN
    Tematy:
    Barremian
    Brachiopoda
    Cretaceous
    paleobiogeography
    Rhynchonellid
    Serbia
    Tetrarhynchiidae
    paleontology
    phylogenetic implication
    rhynchonellid brachiopod
    shell microstructure
    systematics
    taxonomy
    Opis:
    A new rhynchonellide brachiopod genus Antulanella is erected based on the examination of the external and internal morphologies and shell microstructure of “Rhynchonella pancici”, a common species in the Barremian shallow−water limestones of the Carpatho−Balkanides of eastern Serbia. The new genus is assigned to the subfamily Viarhynchiinae, family Tetrarhynchiidae. The shell of Antulanella is small to rarely medium−sized, subglobose, subcircular, fully costate, with hypothyrid rimmed foramen. The dorsal euseptoidum is much reduced. The dental plates are thin, ventrally divergent. The hinge plates are straight to ventrally convex. The crura possess widened distal ends, rarely raduliform or canaliform. The shell is composed of two calcitic layers. The secondary layer is fine fibrous, homogeneous built up of predominantly anisometric anvil−like fibres. Although data on the shell microstructure of post−Palaeozoic rhynchonellides are still incomplete, it is possible to distinguish two types of secondary layer: (i) fine fibrous typical of the superfamilies Rhynchonelloidea and Hemithiridoidea and (ii) coarse fibrous typical of the superfamilies Pugnacoidea, Wellerelloidea, and Norelloidea. The new genus Antulanella has a fine fibrous microstructure of the secondary layer, which is consistent with its allocation in the Hemithiridoidea. Antulanella pancici occurs in association with other brachiopods showing strong Peritethyan affinity and close resemblance to the Jura fauna (= Subtethyan fauna).
    Źródło:
    Acta Palaeontologica Polonica; 2007, 52, 4
    0567-7920
    Pojawia się w:
    Acta Palaeontologica Polonica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Phosphate replicated and replaced microstructure of molluscan shells from the earliest Cambrian of China
    Autorzy:
    Feng, W
    Sun, W.
    Powiązania:
    https://bibliotekanauki.pl/articles/21263.pdf
    Data publikacji:
    2003
    Wydawca:
    Polska Akademia Nauk. Instytut Paleobiologii PAN
    Tematy:
    microstructure
    fossil
    shell
    biomineralization
    Mollusca
    China
    mollusc
    Cambrian
    paleontology
    Opis:
    The earliest Cambrian Meishucunian phosphoritic succession in eastern Yunnan,China,contains well−preserved molluscan shells that offer insights into the early evolution of skeletonization. Phosphate internal moulds,phosphate replaced originally carbonate shells,and phosphate coatings show lamello−fibrillar structure,prismatic structure,and regularly foliated structure. The lamello−fibrillar structure appears earlier in the fossil record than laminar structures such as nacreous or foliated structures. It has been identified in fossil mollusks,which occur in China as early as the lower phosphate layer of the Zhongyicun Member of the Meishucunian. Therefore,the lamello−fibrillar structure appears to be primitive in mollusks. The lamello−fibrillar and prismatic aragonite is the most common shell material of molluscan skeletons in the Early Cambrian Meishucunian and equivalents around the world. Although the early molluscan microstructure is not so diverse as that of extant mollusks,it may be of use in high rank taxonomic classification as shown by the early conchiferan mollusks discussed here. These mollusks are characterized by the horizontal fibrillae that are layered and parallel,and thereby differ from hyoliths,in which the horizontal fibrillae appear to be in the form of the bundles of fibres that can branch or anastomose.
    Źródło:
    Acta Palaeontologica Polonica; 2003, 48, 1
    0567-7920
    Pojawia się w:
    Acta Palaeontologica Polonica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Microstructural Characterization and Mechanical Behavior of Copper Matrix Composites Reinforced by B4C and Sea Shell Powder
    Autorzy:
    Sankar, M.
    Pradeep Devaneyan, S.
    Peter Pushpanathan, D.
    Myszka, D.
    Powiązania:
    https://bibliotekanauki.pl/articles/106969.pdf
    Data publikacji:
    2018
    Wydawca:
    Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
    Tematy:
    Cu-base MMC
    Sea Shell Powder-B4C Reinforcement
    wear properties
    microstructure
    Opis:
    This paper investigates the microstructural and mechanical properties of copper metal matrix composites reinforced with B4C and crushed sea shell particles (fabricated using powder metallurgy). In powder form, copper is widely used in structural applications. Copper also possesses very good electrical and thermal conductivity, ductility, and corrosion resistance. B4C is the third-hardest-known material that also possesses excellent toughness and wear resistance. Sea shells are readily available along coastal areas. Therefore, an attempt has been made in this work to investigate the feasibility of its utilization in powder metallurgy. Two batches of samples were prepared. In the first batch, the percentage of boron carbide and copper powder were varied, and seashell powder was not included. In the second batch, the percentages of B4C, copper, and sea shell powder were varied in order to assess the change effected by the sea shell material. The sintered samples of both batches were subjected to microstructural characterization to ascertain the homogeneous distribution of the reinforcements. The microhardness and wear resistance of all of the fabricated samples were assessed. The results confirmed that the inclusion of 2% sea shell powder (by weight) with 10% boron carbide improved the wear resistance and hardness of the composite.
    Źródło:
    Journal of Casting & Materials Engineering; 2018, 2, 1; 24-29
    2543-9901
    Pojawia się w:
    Journal of Casting & Materials Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Shell microstructures in Early Cambrian molluscs
    Autorzy:
    Kouchinsky, A
    Powiązania:
    https://bibliotekanauki.pl/articles/23294.pdf
    Data publikacji:
    2000
    Wydawca:
    Polska Akademia Nauk. Instytut Paleobiologii PAN
    Tematy:
    skeletal fossil
    microstructure
    shell
    biomineralization
    mollusc
    Early Cambrian
    mollusc-like organism
    taxonomy
    Cambrian
    paleontology
    Opis:
    The affinities of a considerable part of the earliest skeletal fossils are problematical, but investigation of their microstructures may be useful for understanding biomineralization mechanisms in early metazoans and helpful for their taxonomy. The skeletons of Early Cambrian mollusc-like organisms increased by marginal secretion of new growth lamellae or sclerites, the recognized basal elements of which were fibers of apparently aragonite. The juvenile part of some composite shells consisted of needle-like sclerites; the adult part was built of hollow leaf-like sclerites. A layer of mineralized prism-like units (low aragonitic prisms or flattened spherulites) surrounded by an organic matrix possibly existed in most of the shells with continuous walls. The distribution of initial points of the prism-like units on a periostracurn-like sheet and their growth rate were mostly regular. The units may be replicated on the surface of internal molds as shallow concave polygons, which may contain a more or less well-expressed tubercle in their center. Tubercles are often not enclosed in concave polygons and may co-occur with other types of textures. Convex polygons seem to have resulted from decalcification of prism-like units. They do not co-occur with tubercles. The latter are interpreted as casts of pore channels in the wall possibly playing a role in biomineralization or pits serving as attachment sites of groups of mantle cells. Casts of fibers and/or lamellar units may overlap a polygonal texture or occur without it. They may reflect an inner layer consisting of aragonitic fibers fused into more or less well-developed lamellar units. It seems that nacreous and crossed-lamellar aragonitic microstructures evolved in the Cambrian from such lamellar aragonitic microstructures independently in different groups of molluscs.
    Źródło:
    Acta Palaeontologica Polonica; 2000, 45, 2
    0567-7920
    Pojawia się w:
    Acta Palaeontologica Polonica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Thermal analysis of epoxy based coconut fiber-almond shell particle reinforced biocomposites
    Analiza cieplna biokompozytów epoksydowych umacnianych łuskami migdałowca i włóknami kokosowymi
    Autorzy:
    Chaudhary, A. K.
    Gope, P. C.
    Singh, V. K.
    Suman, A. R.
    Verma, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/175615.pdf
    Data publikacji:
    2014
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    biocomposites
    almond shell
    coconut fiber
    microstructure
    thermal analysis
    biokompozyt
    łuski migdałowca
    włókno kokosowe
    mikrostruktura
    analiza cieplna
    Opis:
    In this research, the suitability of almond shell and coconut fiber as a renewable agricultural residue for manufacturing of biocomposite to be used as a replacement of wood was investigated. The use of agriculture waste as a reinforcement in composite may result in several environmental and socioeconomic benefits. Biocomposite containing different weight percentage of almond shell particle (10, 20, 30, 40 and 50 wt%) and coconut fiber (2, 4 and 6 wt%) mixed with 20 wt% of almond shell particles were made using epoxy resin and 0.5 wt% of Tricresyl Phosphate. Thermal stability test and morphology (SEM) of the biocomposite were determined.
    W artykule przedstawiono analizę wyników badań trwałości materiałów biokompozytowych umacnianych łuskami migdałowca i włóknami kokosowymi, używanych jako zamienniki drewna. Zastosowanie odpadów rolniczych jako elementów umacniających materiały kompozytowe pozytywnie oddziałuje zarówno na środowisko naturalne, jak i kryteria ekonomiczne ich producentów. W badaniach stosowano materiały biokompozytowe o zawartości cząstek łusek migdałowca od 10 do 50% mas. oraz włókien kokosowych 2, 4 i 6% mas. Osnową wytworzonych kompozytów była żywica epoksydowa z dodatkiem fosforanu trikrezylowego 0,5% mas. Wykonano badania stabilności cieplnej wytworzonych biokompozytów oraz ich mikrostruktury przy zastosowaniu mikroskopu skaningowego SEM.
    Źródło:
    Advances in Manufacturing Science and Technology; 2014, 38, 2; 37-50
    0137-4478
    Pojawia się w:
    Advances in Manufacturing Science and Technology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The oldest brachiopods from the lower Cambrian of South Australia
    Autorzy:
    Topper, T.P.
    Holmer, L.E.
    Skovsted, C.B.
    Brock, G.A.
    Balthasar, U.
    Larsson, C.M.
    Stolk, S.P.
    Harper, D.A.T.
    Powiązania:
    https://bibliotekanauki.pl/articles/22055.pdf
    Data publikacji:
    2013
    Wydawca:
    Polska Akademia Nauk. Instytut Paleobiologii PAN
    Tematy:
    brachiopod
    Cambrian
    South Australia
    Brachiopoda
    Tommotiida
    Paterinida
    Askepasma
    microstructure
    morphology
    shell
    Arrowie Basin
    Lower Cambrian
    Australia
    paleontology
    Opis:
    The morphology and organophosphatic shell structure of the paterinate brachiopod Askepasma is documented using new and previously collected specimens from the lower Cambrian of South Australia. Lack of adequately preserved material has seen the majority of paterinate specimens previously reported from South Australia referred to the genus Askepasma and treated under open nomenclature. Large collections of paterinates from the lower Cambrian Wilkawillina, Ajax, and Wirrapowie limestones in the Arrowie Basin, South Australia have prompted redescription of the type species Askepasma toddense and the erection of a new species, Askepasma saproconcha sp. nov. Askepasma saproconcha sp. nov. currently represents the oldest known brachiopod from the lower Cambrian successions in South Australia with a FAD in pre−trilo− bitic (Terreneuvian, Cambrian Stage 2, lower Atdabanian) strata in the basal part of the Wilkawillina and Wirrapowie limestones. Askepasma toddense predominantly occurs in Abadiella huoi Zone equivalent strata (Unnamed Cambrian Se− ries 2, Stage 3, middle–upper Atdabanian) in the upper part of the lower Wilkawillina, Wirrapowie, and Ajax limestones. The shell microstructure of Askepasma suggests a proximal stem group position within the Brachiopoda and similarities with tommotiid taxa provides further evidence that the ancestry of crown group brachiopods is firmly entrenched within the Tommotiida.
    Źródło:
    Acta Palaeontologica Polonica; 2013, 58, 1
    0567-7920
    Pojawia się w:
    Acta Palaeontologica Polonica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-6 z 6

      Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies