14,663 research outputs found
Panus bambusinus N. Vinjusha & T. K. A. Kumar 2022, comb. nov.
No full textPanus bambusinus (T.K.A. Kumar & Manim.) N. Vinjusha & T.K.A. Kumar comb. nov. MycoBank No: MB 842791 Basionym:— Lentinus bambusinus T.K.A. Kumar & Manim., in Mycotaxon 92: 119 (2005) The species is characterized by graminicolous basidiomata, a dimitic hyphal system, with sparsely branched skeletal hyphae, presence of refractive gloeocystidia, ellipsoid to ovoid basidiospores, and absence of hyphal pegs and skeleto ligative hyphae (Kumar & Manimohan 2005; Vinjusha & Kumar 2021).Published as part of Kumar, T. K. Arun, 2022, Validation of Panus bambusinus and P. roseus (Panaceae, Polyporales), pp. 235-236 in Phytotaxa 533 (4) on page 235, DOI: 10.11646/phytotaxa.533.4.7, http://zenodo.org/record/609165
Natural Materials—Interesting Candidates for Carbon Nanomaterials
No full textThis review sums up the techniques used for the synthesis of carbon nanotubes (CNTs), carbon nanofibers (CNFs), and carbon nanospheres (CNSs) by employing catalysts of natural origin. Establishing large-scale production and commercial applications of CNTs for a sustainable society is still of high apprehension. In this regard, one of the major factors is the starting materials such as precursors and catalyst sources. However, natural materials contain a minor quantity of metals or metal oxides and could be employed as a catalyst source for the synthesis of CNTs, providing the possibility to replace expensive catalyst sources. A large number of successful studies have been completed so far and confirm that these developed methods for carbon nanomaterials synthesis exhibiting high quality from common natural materials are not only possible but, most importantly, promising and scalable. This review also highlights purification methods and recent promising applications of as-synthesized CNTs
Panus bambusinus N. Vinjusha & T. K. A. Kumar, comb. nov.
No full text<i>Panus bambusinus</i> (T.K.A. Kumar & Manim.) N. Vinjusha & T.K.A. Kumar <i>comb. nov.</i> <p> Basionym:— <i>Lentinus bambusinus</i> T.K.A. Kumar & Manim., Mycotaxon 92: 119 (2005) (Fig. 1)</p> <p> Description: <i>—Basidiomata</i> annual, small to large, solitary or caespitose, centrally stipitate. <i>Pileus</i> 15‒200 mm diam, weakly depressed in the centre or infundibuliform, concentric zone absent, squamulose when young, almost glabrous with age, wrinkled in dried specimens, yellowish brown to light brown, margin entire, dentate or irregularly lobed. <i>Hymenophore</i> lamellate. Lamellae close, decurrent, sometimes dichotomously branched, edge finely fimbriate under a 10×lens, lamellulae present in 3‒4 tiers, yellowish white. <i>Context</i> up to 6 mm thick, white. <i>Stipe</i> 40‒100 mm long, 5‒25 mm thick, central, cylindrical, even in younger specimens, tapering towards the base in older specimens, surface glabrous to matted fibrillose or strigose, sometimes with sparse and scattered squamules, yellowish white to brown, tissue solid, cream. <i>Odour</i> not distinct. <i>Spore print</i> not observed.</p> <p> <i>Basidiospores</i> 5–6.5 × 4–4.5 μm, Q=1.3–1.7, Q m =1.32, ellipsoid to ovoid, hyaline, smooth, thin-walled, with refractive guttules, inamyloid in Melzer’s reagent. <i>Basidia</i> 20‒37 × 5‒7 μm, clavate, 4 sterigmate. <i>Cheilocystidia</i> present, 22‒68 × 3‒5 μm, versiform, generally flexuose, branched towards apex, hyaline, smooth, thin-walled with obtuse tips. <i>Gloeocystidia</i> frequent on edges and sides of lamellae, 24‒48 × 6‒15 μm, mostly fusoid with acuminate tips, or narrowly clavate, hyaline, smooth, thin-walled. <i>Hyphal pegs</i> absent. <i>Hymenial trama</i> radially arranged, and dimitic. Generative hyphae 2‒6 μm wide, hyaline, smooth, thin to slightly thick-walled (up to 1 μm), branched, with clamp connections. Skeletal hyphae dominant, 2‒4 μm wide, hyaline, thick-walled (1 μm), mostly unbranched, rarely branched, septations not observed. Skeleto ligative hyphae not observed. <i>Pileal trama</i> radially arranged. Generative hyphae 2‒6 μm wide, rarely inflated up to 10 µm, hyaline, smooth, thin to slightly thick-walled (up to 1 μm), branched, with clamp connections. Skeletal hyphae dominant, 2‒6 μm wide, hyaline, thick-walled (1 μm), mostly unbranched, rarely branched, septations not observed. Skeleto ligative hyphae not observed. <i>Pileipellis</i> with scattered trichodermial patches, up to 100 μm long, made of hyphae that are 2‒4 μm wide, hyaline, thin to slightly thick-walled (up to 1 µm), with obtuse ends. <i>Stipe trama</i> interwoven. Generative hyphae 2‒5 μm wide, hyaline, smooth, thin to slightly thickwalled (up to 1 μm), branched, with clamp connections. Skeletal hyphae 2‒5 μm wide, hyaline, thick-walled (1 μm), mostly unbranched, rarely branched, septations not observed. <i>Stipitipellis</i> similar as pileipellis, made of hyphae that are 2‒4 μm wide, hyaline, mostly thin-walled, with obtuse ends.</p> <p> Specimens examined:— INDIA. Kerala State: Malappuram district, Thenjipalam, Calicut University Campus, Alt. 2 m, 1.1339° N, 75.8940° E, on dead roots and rhizomes of <i>Bambusa bambos</i>, 2 July 2004, <i>Arun Kumar AK61</i> <i>a;</i> 5 July 2004, <i>Arun Kumar AK61</i> <i>b</i> (part of the holotype deposited at L); 18 October 2004, <i>Arun Kumar AK61</i> <i>c</i>; 20 October 2004, <i>Arun Kumar AK61</i> <i>d</i>; 26 October 2004, <i>Arun Kumar AK61</i> <i>e</i>.</p>Published as part of <i>Arun Kumar, T. K., 2021, Two new combinations in the genus Panus (Panaceae, Polyporales) based on morphology and molecular phylogeny, pp. 287-294 in Phytotaxa 514 (3)</i> on page 289, DOI: 10.11646/phytotaxa.514.3.8, <a href="http://zenodo.org/record/5316276">http://zenodo.org/record/5316276</a>
Panus roseus N. Vinjusha & T. K. A. Kumar 2022, comb. nov.
No full textPanus roseus (Karun., K.D. Hyde & Zhu L. Yang) N. Vinjusha & T.K.A. Kumar comb. nov. MycoBank No: MB 842792 Basionym:— Lentinus roseus Karunarathna, K.D. Hyde & Zhu L. Yang, in Karunarathna, Yang, Zhao, Vellinga, Bahkali, Chukeatirote & Hyde, Mycol. Progr. 10 (4): 392 (2011) Panus roseus is characterized by a relatively small basidiome, with coriaceous, deeply cyathiform, pink-coloured pileus, dimitic hyphal system, with thick-walled unbranched skeletal hyphae, presence of clavate, cheilocystidia and metuloids, and ellipsoid to elongate basidiospores (Karunarathna et al. 2011).Published as part of Kumar, T. K. Arun, 2022, Validation of Panus bambusinus and P. roseus (Panaceae, Polyporales), pp. 235-236 in Phytotaxa 533 (4) on page 235, DOI: 10.11646/phytotaxa.533.4.7, http://zenodo.org/record/609165
Continuity and settlement structure--a study of tradiational and colonial spatial patterns in Benares, India
No full textThesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 1992.Includes bibliographical references (p. 92-100).by Arun Kumar Rewal.M.C.P
Feasbility study of implementation of auto storage & retrival system (AS/RS) in a manufacturing environment
No full textThis project studies the implementation of Auto Storage and Retrieval System (AS/RS) in the Printed Circuit Board Assembly (PCBA) by one of the leading computer manufacturing companies in Singapore. There are basically various phases involved in the entire ASRS system implementation and this project looks at the current trends and the future. (Dr. Arun Kumar)Master of Science (Logistics
Clavaria viriditincta Krishnapriya & T. K. A. Kumar 2023, sp. nov.
No full textClavaria viriditincta Krishnapriya & T.K.A. Kumar, sp. nov. (Fig. 1) MycoBank no:—MB846541 Type:— INDIA. Kerala State, University of Calicut campus (11.11 oN, 75.89 oE, altitude 32 m), 06 June 2022, Krishnapriya K., (holotype, ZGCKP247). Etymology:—‘ viriditincta’ refers to the green colour of the basidiomata. Diagnosis:— Clavaria viriditincta differs from other Clavaria species by its large, distinclty green basidiomata, ellipsoid basidiospores (6–7 × 4–5 µm), and inflated hyphae with ampulliform septal swellings. Description:— Basidiomata 30–80 × 3–5 mm, simple, unbranched, cylindrical, solid when young, becoming fistulose with age, terete in cross section, apex acute to subacute, glabrous, fertile throughout, deep green, darker at the extreme apex, no colour change on bruising, context fleshy, without any distinct odour, no colour reaction in Fe 3 Cl and KOH. Basidiospores 6–7 × 4–5 µm (Q =1.2–1.7 µm, Q m =1.4 µm), ellipsoid, smooth, thin-walled, hyaline, guttulate, apiculus prominent (up to 1 µm long), inamyloid, cyanophilic in cotton blue. Basidia 30–40 × 7–8 µm, agguttulate, clavate, without basal clamp-connection, sterigmata 4 (up to 5 µm long). Hymenium 20–30 µm wide. Subhymenium 40–50 µm wide. Context composed of generative hyphae, 4–10 µm wide, inflated up to 20 µm wide, interwoven, septate, with ampulliform septal swellings, hyaline, thick-walled (up to 1 µm, inamyloid, cyanophilic in cotton blue. Hyphal clamp-connections absent. Habitat and distribution:—on soil, among leaf litter, gregarious. This species was collected from an area dominated by Hevea brasiliensis. Additional specimens examined:— INDIA. Kerala State, Malappuram District, University of Calicut campus, alt. 32 m, 06 June 2022, Krishnapriya K., (ZGCKP247 A).Published as part of Kumar, T. K. Arun, 2023, A new species of Clavaria from India, pp. 197-202 in Phytotaxa 601 (2) on page 199, DOI: 10.11646/phytotaxa.601.2.6, http://zenodo.org/record/812963
Micro-Raman investigation of the nanostructure evolution of Boron-doped SiOC powders after pyrolysis at high temperature
No full textPolymer-derived ceramics, constitute a class of ceramic materials obtained through pyrolysis of pre-ceramic polymers. Initial examples of PDCs were the silicon carbide fibers for high temperature structural applications. Recently, boron doped silicon-based ceramics with enhanced high-temperature stability have attracted great attention [1]. SiOC:B samples, with different B content, were synthesized using the sol gel method at different B concentration and the synthesized samples underwent pyrolysis at 1200°C and 1400°C. Herein, we present the spectroscopic study of thermally treated SiOC:B samples doped with increasing amounts of boron. The study of has been done using micro Raman spectroscopy. In pure SiOC powders, treated at 1400°C , the two D and G bands which are barely visible in SiOC sample treated at 1200°C , turn out in the form of well resolved peaks at about 1332 cm-1 and 1609 cm-1. The temperature evaluation of these two fingerprints indicates that the graphitic component of SiOC powders undergoes an important structural rearrangement. In samples with higher concentration of B, treated at 1400°C, there is a clear evidence of the D’ at 1605 cm-1, G’(2D) at 2658 cm-1 and D+G at 2913 cm-1.The 2D band is sensitive to the stacking of graphene sheets, which becomes well defined at 1400°C
A Unified Shell model for Buoyancy-Driven Turbulence
No full textWe construct a unified shell model for stably stratified and convective turbulence. Shell model simulation of stably stratified flow in turbulent regime exhibit Bolgiano-Obukhbov (BO) scaling in which the kinetic energy spectrum varies as . However, simulation of convective turbulence shows Kolmogorov's spectrum. These results are consistent with the direct numerical simulations of Kumar {\em et al.} [Phys. Rev. E {\bf 90}, 023016 (2014)]. We also observe a dual scaling ( and ) for a limited range of parameters in stably stratified flow
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