scholarly journals Possible route to efficient thermoelectric applications in a driven fractal network

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kallol Mondal ◽  
Sudin Ganguly ◽  
Santanu K. Maiti

AbstractAn essential attribute of many fractal structures is self-similarity. A Sierpinski gasket (SPG) triangle is a promising example of a fractal lattice that exhibits localized energy eigenstates. In the present work, for the first time we establish that a mixture of both extended and localized energy eigenstates can be generated yeilding mobility edges at multiple energies in presence of a time-periodic driving field. We obtain several compelling features by studying the transmission and energy eigenvalue spectra. As a possible application of our new findings, different thermoelectric properties are discussed, such as electrical conductance, thermopower, thermal conductance due to electrons and phonons. We show that our proposed method indeed exhibits highly favorable thermoelectric performance. The time-periodic driving field is assumed through an arbitrarily polarized light, and its effect is incorporated via Floquet-Bloch ansatz. All transport phenomena are worked out using Green’s function formalism following the Landauer–Büttiker prescription.

2018 ◽  
Vol 52 (2) ◽  
pp. 397-406
Author(s):  
A. B. Ismailov ◽  
G. P. Urbanavichus

The lichens and lichenicolous fungi of high mountainous landscapes of Samurskiy Ridge were studied in altitudinal range 2400–3770 m a. s. l. for the first time and 112 species are recorded. Among them 33 species, 10 genera (Arthrorhaphis, Baeomyces, Calvitimela, Epilichen, Lambiella, Psorinia, Rufoplaca, Sagedia, Sporastatia, Tremolecia) and 4 families (Anamylopsoraceae, Arthrorhaphidaceae, Baeomycetaceae, Hymeneliaceae) are new for Dagestan, six species (Buellia uberior, Carbonea atronivea, Lecanora atrosulphurea, Lecidea fuliginosa, L. swartzioidea, Rhizoplaca subdiscrepans) are reported for the first time for the Greater Caucasus and two species (Acarospora subpruinata and Rhizocarpon postumum) — for the North Caucasus. Most of the new findings were collected from 3500–3770 m a. s. l.


2020 ◽  
Vol 147 (2) ◽  
pp. 153-163
Author(s):  
Kirsten Dzwiza

SummaryThere are only a few sequences of ancient magic signs known to us today that have been preserved on multiple artefacts. A previously unnoticed sequence of 17 signs on a gem in the Museum of Fine Arts in Vienna occurs with minor but significant variations on two other gems in the State Museum of Egyptian Art in Munich. The Viennese gem is dated to the 16th century and is documented as a drawing in a 17th century publication. The first Munich gem has been assigned to the Graeco-Roman period. The second gem, which, according to the inventory card of the museum, also belongs to the Graeco-Roman period, is published here for the first time. A comparative study of the three gems and the drawing has lead to a number of new findings, including the re-dating of the Munich gems.


Foods ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 410
Author(s):  
Irene Sánchez-Gavilán ◽  
Esteban Ramírez ◽  
Vicenta de la Fuente

Many halophytes have great nutritional and functional potential, providing chemical compounds with biological properties. Salicornia patula Duval-Jouve is a common euhalophyte from saline Mediterranean territories (Spain, Portugal, France, and Italy). In the present work we quantified for the first time the bioactive compounds in S. patula (total phenolic compounds and fatty acids), from Iberian Peninsula localities: littoral-coastal Tinto River basin areas (southwest Spain, the Huelva province), and mainland continental territories (northwest and central Spain, the Valladolid and Madrid provinces). Five phenolic acids including caffeic, coumaric, veratric, salicylic, and transcinnamic have been found with differences between mainland and coastal saltmarshes. S. patula contain four flavonoids: quercetin-3-O-rutinoside, kaempferol/luteolin, apigenin 7-glucoside, and pelargonidin-3-O-rutinoside. These last two glycosylated compounds are described for the first time in this genus of Chenopodiaceae. The fatty acid profile described in S. patula stems contains palmitic, oleic, and linoleic acids in high concentrations, while stearic and long-chain fatty acids were detected in low amounts. These new findings confirm that S. patula is a valuable source of bioactive compounds from Mediterranean area.


2021 ◽  
Vol 53 (1) ◽  
pp. 81-94
Author(s):  
Annina Kantelinen ◽  
Marko-Tapio Hyvärinen ◽  
Paul M. Kirika ◽  
Leena Myllys

AbstractThe genus Micarea was studied for the first time in the Taita Hills, Kenya. Based on new collections and existing data, we reconstructed a phylogeny using ITS, mtSSU and Mcm7 regions, and generated a total of 27 new sequences. Data were analyzed using maximum likelihood and maximum parsimony methods. Based mainly on new collections, we discovered four undescribed well-supported lineages, characterized by molecular and phenotypic features. These lineages are described here as Micarea pumila, M. stellaris, M. taitensis and M. versicolor. Micarea pumila is characterized by a minutely granular thallus, small cream-white or pale brownish apothecia, small ascospores and the production of prasinic acid. Micarea stellaris has a warted-areolate thallus, cream-white apothecia usually darker at the centre, a hymenium of light grey or brownish pigment that dissolves in K, and intense crystalline granules that appear as a belt-like continuum across the lower hymenium when studied in polarized light. Micarea taitensis is characterized by a warted-areolate thallus and cream-white or yellowish apothecia that sometimes produce the Sedifolia-grey pigment. Micarea versicolor is characterized by a warted-areolate, sometimes partly granular thallus and apothecia varying from cream-white to light grey to blackish in colour. This considerable variation in the coloration of its apothecia is caused by an occasional mixture of the Sedifolia-grey pigment in the epihymenium and another purplish brown pigment in the hymenium. Micarea stellaris, M. taitensis and M. versicolor produce methoxymicareic acid. The main distinguishing characters are presented in a species synopsis. Three of the new species are nested in the M. prasina group, and the fourth one (M. taitensis) resolves as a basal taxon to the M. prasina group. The new species inhabit montane cloud forests, which have fragmented dramatically throughout the Eastern Arc Mountains in recent decades.


Author(s):  
ÖMER FARUK ELMAS ◽  
NECMETTİN AKDENİZ

Background and Aim: Verrucous epidermal nevi are cutaneous hamartomas having many clinical variants. Dermoscopic features of verrucous epidermal nevus have rarely been investigated. We aimed to identify dermoscopic findings of the entity which will facilitate the diagnostic process by reducing the use of invasive diagnostic methods. Material and Methods: The study included the patients with histopathologically approved verrucous epidermal nevus. Clinical, dermoscopic and histopathological features of the patients were retrospectively reviewed and the findings identified were recorded. Dermoscopic examination was performed with a polarized-light handheld dermoscope with 10-fold magnification. Results: The most common dermoscopic features were thick brown circles, thick brown branched lines and terminal hairs. The most common vessel pattern was dotted vessels. Branched thick brown lines, brown globules, brown dots forming lines, serpiginous brown dots, white and brown exophytic papillary structures, fine scale, thick adherent scale and cerebriform structures were the other findings. Conclusion: We observed many vascular and non-vascular dermoscopic findings which have not been described previously for the entity. Dermoscopic examination of the verrucous epidermal nevi may lead more reliable clinical interpretation and thus it may reduce the need for histopathological investigation. Keywords: dermoscopy, large brown circles, verrucous epidermal nevus


1999 ◽  
Vol 588 ◽  
Author(s):  
Y. Ohno ◽  
S. Takeda

AbstractWe have developed an apparatus for polarized cathodoluminescence (CL) spectroscopy combined with transmission electron microscopy (TEM), that enables us to obtain simultaneously structural data in higher spatial resolution by TEM and polarized luminescence spectra by CL of the same microscopic area. The polarized-CL/TEM method is very useful to study the optical properties of low-dimensional microstructures in semiconducting materials. We have applied the method to examine the optical property of antiphase boundaries in CuPt-ordered GaInP2 and found, for the first time, the polarized light emission from the APBs whose habit planes are parallel to the (T11) and (1T0) atomic planes.


2020 ◽  
Vol 41 (2) ◽  
pp. 213-220
Author(s):  
Fermín Del Egido ◽  
Patricio Bariego ◽  
Alberto Rodríguez ◽  
María Santos Vicente

We provide new records and notes on 25 protected and/or threatened vascular plant species in Castilla y León. Some of them illustrate not only new findings but also an interesting expansion of their geographic range. Eight taxa are reported for the first time in some provinces, while eleven of them were two or three times previously reported.


2019 ◽  
Vol 85 (1II)) ◽  
pp. 73-76 ◽  
Author(s):  
V. I. Otmakhov ◽  
Yu. S. Sarkisov ◽  
A. N. Pavlova ◽  
A. V. Obukhova

150 years ago D. I. Mendeleev revealed the Periodic law to the world and since that time periodic dependencies have been increasingly used in various fields of basic and applied sciences. For the first time we consider the regularities of periodic dependences of the concentration of chemical elements in the ash residue of human hair on the number of the element. Such dependencies for various regions of Russia reveal strictly individual character. It is shown that distributions of the chemical elements for men and women also differ, as well as the distributions determined for the same groups in inhabitants of different regions of residence and depend to a significant extent on the genetic and physiological characteristics of human organism, variability of environmental conditions, earlier diseases and other impacts. This means that population of different urban regions (e.g., Siberian region) is characterized by a strictly individual distribution of biogenic elements. A hypothesis has been put forward that extrema observed on the studied dependences can be a kind of code for a given locality, reflecting correlation with various factors of genetic and ecological nature.


Zootaxa ◽  
2021 ◽  
Vol 4949 (2) ◽  
pp. 381-397
Author(s):  
S. PRASANTH NARAYANAN ◽  
S. SATHRUMITHRA ◽  
R. ANUJA ◽  
G. CHRISTOPHER ◽  
A.P. THOMAS ◽  
...  

Three new species of Moniligaster Perrier, 1872, namely M. bahli Narayanan & Julka, sp. nov., M. blakemorei Narayanan & Julka, sp. nov. and M. keralensis Narayanan & Julka, sp. nov. are described from materials collected from the Indian state of Kerala. Moniligaster cernosvitovi Gates, 1962, Moniligaster horsti Gates, 1940, Moniligaster michaelseni Gates, 1940 and Moniligaster stephensoni Gates, 1940 are recorded for the first time from the state. With the new findings, a total of 10 Moniligaster species are known from Kerala. Moniligaster species are restricted to southern peninsular India, except Moniligaster ivaniosi Manazhy, 2011, decribed from the Andaman Islands, outside the currently known distributional range of the genus. Hence we critically reviewed the original description and reinvestigated the holotype. As a result, Moniligaster ivaniosi is considered a junior synonym of Drawida nepalensis Michaelsen, 1907. 


2020 ◽  
Vol 22 (28) ◽  
pp. 16165-16173
Author(s):  
Hangbo Zhou ◽  
Gang Zhang ◽  
Yong-Wei Zhang

We perform quantum master equation calculations and machine learning to investigate the thermoelectric properties of multiple interacting quantum dots, including electrical conductance, Seebeck coefficient, thermal conductance and ZT.


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