142,819 research outputs found
Limonius (Pheletes) californicus
No full textWithin the framework of this work, the type material (two syntypes) of Cardiophorus californicus Mannerheim, 1843 was studied in detail; it was photographed. The author of the original description did not identify the holotype, which, in accordance with the provisions of the International Code of Zoological Nomenclature, entails the need to distinguish the lectotype and paralectotype for the subsequent supposed redescription of the species
Colloidal CdSe Quantum Wells with Graded Shell Composition for Low-Threshold Amplified Spontaneous Emission and Highly Efficient Electroluminescence
No full textSemiconductor nanoplatelets (NPLs) have emerged as a very promising class of colloidal nanocrystals for light-emitting devices owing to their quantum-well-like electronic and optical characteristics. However, their lower photoluminescence quantum yield (PLQY) and limited stability have hampered the realization of their outstanding luminescent properties in device applications. Here, to address these deficiencies, we present a two-step synthetic approach that enables the synthesis of core/shell NPLs with precisely controlled shell composition for engineering their excitonic properties. The proposed CdSe colloidal quantum wells possess a graded shell, which is composed of a CdS buffer layer and a CdxZn1-xS gradient layer, and exhibit bright emission (PLQY 75-89%) in the red spectral region (634-648 nm) with a narrow emission line width (21 nm). These enhanced optical properties allowed us to attain low thresholds for amplified spontaneous emission (down to ∼40 μJ/cm2) under nanosecond laser excitation. We also studied the electroluminescent performance of these NPLs by fabricating solution-processed light-emitting diodes (LEDs). In comparison to NPL-LEDs with CdSe/CdS core/shell NPLs, which exhibit an external quantum efficiency (EQE) value of only 1.80%, a significantly improved EQE value of 9.92% was obtained using graded-shell NPLs, the highest value for colloidal NPL-based-LEDs. In addition, the low efficiency roll-off characteristics of NPL-LEDs enabled a high brightness of up to ∼46 000 cd/m2 with an electroluminescence peak centered at 650 nm. These findings demonstrate the paramount role that heterostructure engineering occupies in enhancing the optoelectronic characteristics of semiconductor NPLs toward practically relevant levels
Ya.N. Kovalenko, S.A. Kurbatov, M.G. Kovalenko. Geographical distribution and biological features of the Cynaeus angustus (LeConte) as an element of native ecosystems, as well as during synanthropization of larger black flour beetle.
No full textGeographical distribution and biological features of the Cynaeus angustus (LeConte) as an element of native ecosystems, as well as during synanthropization of larger black flour beetle.THIS DATASET IS ARCHIVED AT DANS/EASY, BUT NOT ACCESSIBLE HERE. TO VIEW A LIST OF FILES AND ACCESS THE FILES IN THIS DATASET CLICK ON THE DOI-LINK ABOV
Spatially-localized time dependent solutions including turbulence and their interactions in 2D Kolmogorov flow
No full textIn 2D Kolmogorov flow in small aspect ratio domains, spatially-localized solutions such as kink, traveling or time-dependent kink-antikink pars coexist. However, the conservation of the flow rate in the y direction strongly restrict combination of localized solutions and their positioning. We find that by adding a homogeneous flow U y their positioning is controlled and each of localized solutions including a spatially-localized chaos is isolated. Numerical results suggest that these isolated solutions can be elements constructing a whole flow
Finance functions
No full textBykova Y. O. Finance functions / Y. O. Bykova, A. Kovalenko // Тиждень науки-2019. Електротехнічний факультет. Тези доповідей науково-практичної конференції, Запоріжжя, 15-19 квітня 2019 р. / Редкол. : В. В. Наумик (відпов. ред.) Електрон. дані. – Запоріжжя : НУ «Запорізька політехніка», 2019. – С. 25
Characteristics of overlap region in high-Reynolds number turbulent channel flow
No full textDirect numerical simulation of the fully developed turbulent channel flows have been carried out at the Reynolds number based on the friction velocity and the channel half width, 2000, 4000 and 8000. A hybrid 10th order accurate finite difference scheme in the stream and spanwise directions, and a second-order scheme in the wall-normal direction is adapted as the spatial discretization method. We observed the plateau profiles in the indicator function corresponded to the von Karman constant. Furthermore, second peak of streamwise pre-multiplied spectra were appeared in the same wall normal height, 300 < y+ < 600, in case of Re = 4000. Nevertheless, the effects of the lager than the channel half height scale on the streamwise turbulent intensity are fixed contributions without dependence on Reynolds number. These results suggested that the new streamwise vortexes are formed between buffer layer and outer layer with increasing of Reynolds number
La 'circunstancia' de 'Herederos y Pretendientes
No full textIn June 2010, the Ortega y Gasset Foundation hosted a Conference about the “Spanish Philosophical Transition” in order to debate the book of Francisco Vázquez, La filosofía española. Herederos y Pretendientes. Una lectura sociológica (1963-1990), recently published. This paper is the author’s response to criticism raised in the Conference and to published reviews received by this book. First, the author summarized the argument of Herederos y pretendientes. Secondly he responds and takes into account the most important objections against the book’s hypothesis and methodology. Finally the author evaluates the favorable judgments received by the book and suggests the limits of the historian’s task.Fundación Ortega y Gasset-Marañó
Concepto y características generales del precedente judicial como fuente de derecho.
No full textIn the domestic legal system, the role of the judiciary in the field of lawmaking is growing, which, along with the legislative and executive authorities, supplement the existing legal regulation, filling in the gaps and eliminating situations of legal uncertainty. For many years, judicial precedent has been denied in the Soviet theory of law, although there have been attempts to theoretically justify the creation and application of judicial precedent (judicial practice) by higher judicial bodies. This question remains poorly understood and applied to the legal system of modern Russia.En el sistema legal interno, el papel del poder judicial en el campo de la legislación está creciendo, lo que junto con las autoridades legislativas y ejecutivas, complementan la regulación legal existente, llenando los vacíos y eliminando situaciones de inseguridad jurídica. Durante muchos años, el precedente judicial ha sido negado en la teoría del derecho soviético, aunque ha habido intentos de justificar teóricamente la creación y aplicación de precedentes judiciales (práctica judicial) por parte de los órganos judiciales superiores. Esta pregunta sigue siendo insuficientemente estudiada y aplicada al sistema legal de la Rusia moderna
Types of communication barriers
No full textIn this article the author considers communication. Also the author presents the different types of barriers in communication with the practical examples concerning intercultural distinction
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