11,705 research outputs found
Liophloeothrips acaciae Tyagi & Kumar, 2011, sp. n.
No full textLiophloeothrips acaciae sp. n. (Figs. 1–7) Female (macroptera and brachyptera). Body including legs dark brown, fore tibia brownish yellow, tarsi yellow. Antennal segments I–II and VII–VIII dark brown, III yellow, IV–VI yellow basally and brown apically. Fore wing transparent. With character states indicated for genus. Body stout. Head longer than broad (Fig. 1); postocular setae shorter than eyes, expanded at apex; maxillary stylets not close together. Pronotal anteromarginals (am) longer than anteroangulars (aa), epimerals (ep) longer than posteroangulars (pa) (Fig. 1). Metanotum with longitudinal sculpture lines, median setae with apices expanded (Fig. 7). Mesopresternum with two lateral triangles (Fig. 2). Fore wing parallel sided, with 6–10 duplicated cilia; sub-basal wing setae arranged in a one row. Fore tarsus without tooth (Fig. 1). Pelta bell-shaped, broader than in male (Figs. 4, 6). Male (brachyptera). Colour similar to female. Fore tarsus with small tooth. Measurements (holotype female in microns): Total body length 2350. Head, length 220; width at cheeks 205; eye length 95; postocular seta length 70. Pronotum, length 153; width 300; length of major setae - aa 25, am 40, ml 25, pa 70–78, ep 63–87, coxal 25. Length of antenna 275; L(W) of antennal segments I 37 (37), II 55 –57(37), III 75 (35), IV 75 (37), V 65 –70(30–35), VI 63 –65(27–32), VII 48 –50(25), VIII 30–32 (12). Fore femur width 95. Fore wing basal setae, length S 1 35, S 2 50, S 3 55. Tergite IX, length 95; setae S 1 110–113, setae S 2 100–113. Tube, length 193; width at base 90, at apex 50. Paratype male (brachyptera): Body length 1900. Fore wing length 175; basal setae length S 1 37, S 2 42, S 3 42. Tergite IX setae, S 1 105, S 2 38. Material studied. Holotype female (macroptera), India: Karnataka (IIHR, Bangalore), on bark of Acacia auriculiformis, 10.iv. 2006 (Vikas Kumar), deposited in National Bureau of Agriculturallly Important Insects (NBAII), Bangalore. Paratypes: 10 females: 8 (macroptera), 2 (brachyptera), 10 males (brachyptera), 18 larvae collected with holotype (two females and two males deposited in NPC, New Delhi, rest at NBAII, Bangalore, Karnataka). Comments. This species is closely related to L. succinctus and L. pavettae. However, it can be differentiated from these by the shape of the pelta, the metanotal sculpture, and differences in length of the pronotal setae. In the holotype of L. succinctus the anteroangulars and anteromarginals are subequal, but in the holotype of L. pavettae the anteroangulars are longer than the anteromarginals. In L. acaciae the anteromarginals are longer than the anteroangulars. The metanotum has reticulate sculpture and pointed setae in L. succinctus and L. pavettae, but has longitudinal lines and expanded setae in L. acaciae.Published as part of Tyagi, Kaomud & Kumar, Vikas, 2011, The Indian species of Liophloeothrips Priesner (Thysanoptera, Phlaeothripidae) with one new species, pp. 21-31 in Zootaxa 2803 on pages 23-25, DOI: 10.5281/zenodo.20654
Manufacturing of aluminium metal matrix composites by high pressure torsion.
No full textAluminium (Al) and aluminium alloys (AA) are widely utilised in the industry because they are lightweight, inexpensive, ductile, thermally stable, and possess high electrical conductivity. However, poor stiffness, strength, and wear limit their use in aerospace, automobile, and transmission. Metal matrix composites (MMC) have shown the capability to make tailor-made materials to overcome the issues mentioned above. Moreover, nanomaterial-based MMC provides better mechanical properties and wear resistance. However, available methods of producing AA MMC have challenges such as porosity, brittle interfaces, and defects in nano-reinforcement. In the current study, a novel approach has been used to produce nanomaterial-based AA MMC to overcome these challenges. Graphene (Gr), Nanodiamond (ND), and Molybdenum disulfide (MoS2) have been added to CP Al and 7xxx alloys using severe plastic deformation (SPD). The current study provides deep insight into the nature of nanomaterials in metal nanomatrix and the resulting properties for industrial applications, particularly electrical transmission and self-lubrication in the automotive industry. The potential of graphene to improve the strength of aluminium alloy powder has been experimentally studied. Gr AA 7075 MMC is produced by high pressure torsion (HPT) at room temperature. Variations in the concentration of graphene nanosheets and HPT process parameters are applied to optimise the fabrication route. 0.5-1 wt.% Gr AA 7075 MMC were processed through 0.5 to 100 turns of HPT. Also, graphene-free AA 7075 samples were produced using the same process. The samples were studied by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and X-ray diffraction (XRD) line broadening analysis, which revealed the dislocation density and the crystallite size. XRD line broadening revealed a crystallite size of 28 nm for the 1 wt.% Gr AA 7075 MMC after 50 turns of HPT, which illustrates the capacity of HPT to produce a genuinely nanostructured material. Additionally, a comparison of the strength modelling of (1-5%) ND AA 7075 MMC and (1-10%) MoS2 AA 7075 MMC has been done using a similar methodology. The porosity evolution in the Al matrix during the early stages of HPT was analysed. The hardness of the material improved up to 300 % by HPT as compared to annealed bulk AA 7075 to reach a maximum hardness of 310 HV for the 0.5 wt.% Gr AA 7075 MMC processed by 20 turns of HPT. In contrast to cast and solution treated AA 7075, no consistent improvement in hardness is recorded in HPT processed AA 7075 due to artificial ageing. However, XRD results show that the microstructure changed after artificial ageing. In comparison, the addition of ND resulted in softening AA 7075. In contrast, MoS2 AA 7075 MMC have shown higher hardness than two predecessors AA 7075 MMC. A volume-averaged dislocation density model was applied for strength modelling of HPT processed samples. Considering future applications such as aerospace, and automobile parts, a focus on tribological applications of Gr AA 7075 MMC, ND AA 7075 MMC, and MoS2 AA 7075 MMC has been extensively studied. For comprehensive understanding, dry sliding ball on disc wear tests and post-wear analysis were done using tribometer, profilometry, and electron microscopy. Compared to currently available Al alloys, the HPT processed AA 7075 MMC demonstrated a 50% improvement in friction coefficient (0.2–0.3) and wear properties. Generally, Gr and MoS2 reduce the coefficient of friction (COF), whereas ND improves wear resistance in the coarse-grained AA MMC prepared by industrial methods. However, ND AA 7075 MMC shows better friction properties than Gr and MoS2-based AA 7075 MMC. Moreover, MoS2 AA 7075 MMC have a relatively poor wear rate. This study involves a descriptive analysis of the possible unusual role of nano-reinforcements in wear mechanisms. AA are used for electric transmission in many Asian countries, such as India, because of its low cost and good electrical conductivity. Earlier attempts to improve electrical conductivity included alloying and reinforcing with gold and silver. Moreover, considering the electrical properties of graphene, graphene nanosheets have been added to commercially pure Al to make 1% Gr AA 1050 MMC. However, the 4-point probe test shows a 40–60 % reduction in electrical conductivity (IACS). The current study involves the assessment of form factors for measuring the electrical conductivity of AA MMC. Overall, the current study shows the potential of HPT to create a new class of defect-free nanomaterials. Furthermore, experiments are conducted to examine the application-related roles of Gr, ND, and MoS2 in the AA MMC
COMMERCIAL 584\AA PHOTOELECTRON SPECTROMETER
No full textAuthor Institution: Perkin-Elmer LimitedThe design of a commercial 584\AA Photcelectron Spectrometer will be discussed together with some recent research problems investigated by this technique
Open Access to Peer-Reviewed Research through Author/Institution Self-Archiving: Maximizing Research Impact by Maximizing Online Access
No full textAll refereed journals will soon be available online; most of them already are. This means that anyone will be able to access them from any networked desk-top. The literature will all be interconnected by citation, author, and keyword/subject links, allowing for unheard-of power and ease of access and navigability. Successive drafts of pre-refereeing preprints will be linked to the official refereed draft, as well as to any subsequent corrections, revisions, updates, comments, responses, and underlying empirical databases, all enhancing the self-correctiveness, interactivity and productivity of scholarly and scientific research and communication in remarkable new ways. New scientometric indicators of digital impact are also emerging <http://opcit.eprints.org> to chart the online course of knowledge. But there is still one last frontier to cross before science reaches the optimal and the inevitable: Just as there is no longer any need for research or researchers to be constrained by the access-blocking restrictions of paper distribution, there is no longer any need to be constrained by the impact-blocking financial fire-walls of Subscription/Site-License/Pay-Per-View (S/L/P) tolls for this give-away literature. Its author/researchers have always donated their research reports for free (and its referee/researchers have refereed for free), with the sole goal of maximizing their impact on subsequent research (by accessing the eyes and minds of fellow-researchers, present and future) and hence on society. Generic (OAi-compliant) software is now available free so that institutions can immediately create Eprint Archives in which their authors can self-archive all their refereed papers for free for all forever <http://www.eprints.org/>. These interoperable Open Archives <http://www.openarchives.org> will then be harvested into global, jointly searchable "virtual archives" (e.g., <http://arc.cs.odu.edu/>). "Scholarly Skywriting" in this PostGutenberg Galaxy will be dramatically (and measurably) more interactive and productive, spawning its own new digital metrics of productivity and impact, allowing for an online "embryology of knowledge.
Author attribution using profile classifiers
No full textA atribuição autoral (AA) busca identificar um autor de texto a partir de um conjunto de autores conhecidos. Autores deixam rastros em seus textos e é possível identificar características sociolinguísticas baseadas no estilos de escrita refletidos no texto destes autores. A atribuição autoral está cada vez mais demonstrando importância para diversas atividades sociais, em especial para a análise forense. Os trabalhos envolvendo AA demonstram resultados modestos e motivam a exploração de diferentes técnicas para melhorar a acurácia dos modelos atuais. A partir desses pontos, o presente trabalho apresenta uma proposta de pesquisa em nível de mestrado no campo de processamento de língua natural (PLN), com ênfase em AA, com o objetivo geral de melhorar o desempenho de classificadores de atribuição autoral utilizando técnicas de caracterização autoral (CA)Author attribution (AA) seeks to identify a text author from a set of known authors. Authors leave traces in their texts and it is possible to identify sociolinguistic characteristics based on the writing styles reflected in the text of these authors. Author attribution is increasingly showing importance for various social activities, especially forensic analysis. Studies involving AA show modest results and motivate the exploration of different techniques to improve the accuracy of current models. From these perspective, this project presents a master\'s level research proposal in the field of natural language processing (NLP), with an emphasis in AA, with the general objective of improving the performance of AA classifiers using author profiling technique
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Observations of the 57Fe+23 hyperfine transition in clusters of galaxies
No full textWe present a search for the hyperfine transition of the 57Fe+23 ion at 3.071 mm in clusters of galaxies with the ATNF Mopra telescope. The results are compared with a realistic estimate of the peak brightness temperature of the line in a cooling flow cluster A85, using the available X-ray data
THE ANALYSIS OF FIVE ELECTRONIC EMISSION SYSTEMS OF NIOBIUM NITRIDE (NbN) IN THE REGION 5000{\AA} – 6200{\AA}
No full textK. H. Rao and T. M. Dunn, Nature 222, 266 (1969). J. L. Femenias, C. Athenour, and T. M. Dunn, J. Chem. Phys. 63, 2861 (1975).Author Institution:Niobium nitride emission systems have been found at 5l37{\AA}, 5582{\AA}, 5740{\AA}, 5840{\AA}, 5860{\AA}, in addition to the already systems with subbands at 5930{\AA}, 6043{\AA}, and 6192{\AA}. Most of These systems show marked nuclear hyperfine structure of the rotational lines add this has been of assistance in the analysis of all of the systems. Systems of triplet-triplet, singlet-singlet and singlet-triplet are all present and the hyperfine structure also allows assignment of the ground and excited state electron configuration to be made with some confidence
THE 4550 {\AA} BAND SYSTEM OF GLYOXAL
No full textAuthor Institution: Division of Pure Physics, National Research Council“Approximately 45 bands of glyoxal in the region 4000-4660 {\AA} have been photographed in absorption using a 30 ft. Ebert spectrograph with a resolving power of and a dispersion of 1.3 {\AA}/cm. The (0-0) baud near 4550 {\AA}, which WAS studied at a temperature of C, shows fairly well-resolved J- and K- structure characteristic of a perpendicular hand of a near symmetric top molecule. The rotational and vibrational analysis of the speetrum will be discussed.
THE ABSORPTION SPECTRUM OF SODIUM VAPOR FROM 1040{\AA} TO 3500 {\AA}
No full textR. W. Ditchburn and R. D. Hudson, Proc, Roy. SOC. A256, 53 (1960). R. W. Ditchburn, P. J. Jutsum and G. V. Marr, Proc. Roy. Soc. A219, 89 (1953).Author Institution: Space Physics Laboratory, Aerospace Corporation“The absorption of ultraviolet radiation by sodium vapor, and the associated ionization, has been investigated from 1040{\AA} to 3500{\AA} using a two-metre McPherson normal incidence spectrometer and an absorption chamfer of the type described by Ditchburn and The atomic cross section at the series limit (2412 {\AA}) was found to be , in good agreement with the previous result obtained by Ditchburn, Jutsum and The atomic cross section decreases to a minimum at 1900{\AA} and then increases again towards shorter wavelengths. Continuous molecular absorption was observed from 3500{\AA} to 1700{\AA} and ion chamber measurement indicate that this absorption is due to an ionization continuum. Ion current peaks were also seen between 2413{\AA} and 3500{\AA} at wavelengths corresponding to the series absorption lines of the sodium atom. Curves will be presented showing the variation with wavelength of both the atomic cross section and the relative molecular cross section.
ROTATIONAL ANALYSIS OF THE 6125 {\AA} REGION OF NITROGEN DIOXIDE
No full textAuthor Institution: Department of Chemistry, Columbia University; Laboratoire de Photophysique, Moleculaire C.N.R.S. University of Paris-Sud; Department of Chemistry, Columbia UniversityFrom an analysts of the rotationally resolved fluorescence of excited by a narrow band (0.03 {\AA}) tunable dye laser, quantum numbers have been assigned to 80 transitions in the 6l25 {\AA} region. Three band origins are observed in a 20 {\AA} interval, two of which have also been seen in a nozzle beam seeded with A rotational analysis of the 6125 {\AA} and 6127 {\AA} bands is reported, while the small number of transitions assigned to the 6117 {\AA} band presently prevents analysis. Under collision-free conditions ( mTorr) the ``average” radiative lifetimes of the 6117 {\AA} band and the 6125 {\AA} band are sec and sec, respectively. Comments are made concerning the vibrational overlap in this region
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