25 research outputs found

    DDF Construction and D-Brane Boundary States in Pure Spinor Formalism

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    Open string boundary conditions for non-BPS D-branes in type II string theories discussed in hep-th/0505157 give rise to two sectors with integer (R sector) and half-integer (NS sector) modes for the combined fermionic matter and bosonic ghost variables in pure spinor formalism. Exploiting the manifest supersymmetry of the formalism we explicitly construct the DDF (Del Giudice, Di Vecchia, Fubini) states in both the sectors which are in one-to-one correspondence with the states in light-cone Green-Schwarz formalism. We also give a proof of validity of this construction. A similar construction in the closed string sector enables us to define a physical Hilbert space in pure spinor formalism which is used to project the covariant boundary states of both the BPS and non-BPS instantonic D-branes. These projected boundary states take exactly the same form as those found in light-cone Green-Schwarz formalism and are suitable for computing the cylinder diagram with manifest open-closed duality.Comment: 37 pages, typos corrected, some organisational changes mad

    Is Urban Economic Growth Inclusive in India?

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    This paper measures the overall inclusive growth of a city by considering changing trends in the key economic variables based on ‘Borda ranking’ and establishes a relationship between city economic growth and overall city inclusive growth. By using data of 52 large cities in India, this paper finds that higher urban economic growth is associated with an increase in urban inequality, a reduction in urban poverty, and a lower level of overall inclusive growth of a city

    Study on the role of stearic acid and ethylene-bis-stearamide on the mechanical alloying of a biomedical titanium based alloy

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    The present study examines the influence of different contents and types of process control agent (PCA), i.e., stearic acid (SA) and ethylene-bis-stearamide (EBS), on the microstructural evolution and characteristics of Ti-16Sn-4Nb (wt pct) alloy powders and bulk samples. The characterization of the powders and bulk samples was carried out by using chemical analysis, optical microscopy, scanning electron microscopy (SEM) combined with energy-dispersive spectrometry (EDS), and X-ray diffractometry. Results indicated that the powder recovered from the ball milling containers increased with increasing amounts of SA and EBS. Furthermore, adding more SA or EBS to the powder mixture resulted in a considerably smaller particle size, with a flaky-shaped morphology for the given ball milling time. Also, a slightly higher effectiveness was found for EBS when compared to SA. Meanwhile, the addition of both SA and EBS led to a delay in the alloy formation during mechanical alloying (MA) and caused contamination of the material with mainly carbon (C) and oxygen (O). An optimum amount of 1 wt pct PCA led to a good balance between cold welding and fracturing, and thus favored the formation of the titanium alloy. The microstructural observation of the bulk alloy showed a homogeneous distribution of fine Nb-rich &szlig;-phase colonies within the &alpha;-Ti matrix with the addition of PCA less than 1 wt pct.<br /

    Cryomilling for the fabrication of a particulate B4C reinforced Al nanocomposite: Part II. Mechanisms for microstructural evolution

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    Cryomilling was successfully employed to fabricate particulate B4C-reinforced Al matrix nanocomposite powders. In order to investigate the microstructural evolution during cryomilling, composite powders were milled for different times. These powders were collected from the milling chamber and the microstructures were characterized to reveal the formation mechanism for this nanocomposite. The microstructural evolution, including the morphology and size of the milled composite powders, the size and distribution of the B4C, and the dimension of the Al grains, is discussed on the basis of the experimental results.close151

    Efeitos de reguladores vegetais no desenvolvimento e na produtividade do amendoinzeiro (Arachis hypogaea L.) Effects of growth regulators on groundnut development (Arachis hypogaea L.)

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    O trabalho foi realizado com o objetivo de determinar a ação de substâncias de crescimento no desenvolvimento e produtividade do amendoinzeiro, sob condições de casa de vegetação. Plantas de Arachis hypogaea cv. Tatu-53, providas de 4 folhas definitivas, foram pulverizadas com chlormequat 2000 ppm, daminozide 4000 ppm, ácido giberélico 100 ppm, ácido indolilacético 100 ppm, além do controle. Foram determinados: altura das plantas, número de hastes, número de entrenós, comprimento do segundo e quarto entrenós, e o número de folhas. Também foram verificados os números de flores, de frutos e de sementes; peso dos frutos, das sementes, da matéria seca da parte aérea e da matéria seca das raízes do amendoinzeiro. Os resultados obtidos revelaram que daminozide 4000 ppm reduziu a altura, o número de entrenós na haste principal e o comprimento do quarto entrenó. Este produto também aumentou o número de folhas, atrasou a florescência, aumentou o número de flores e tendeu a aumentar o peso seco da parte aérea do amendoinzeiro. Pulverização com chlormequat 2000 ppm e ácido indolilacético 100 ppm, diminuiu a altura da planta e o comprimento do quarto entrenó da haste principal do amendoinzeiro.<br>This research deals with the effects of plant growth regulators on groundnut growth (Arachis hypogaea L. cv. Tatu-53). Plants of groundnut with four leaves grown in pots under greenhouse conditions, were sprayed with chlormequat 2000 ppm, daminozide 4000 ppm, gibberellic acid 100 ppm, indolylacetic acid 100 ppm, mid check treatment. Daminozide 4000 ppm reduced plant height, internode number and the length of the fourth internode. Daminozide increased the number of leaves, retarded flowering, increased the number of flowers and presented a tendency to increase the dry weight of stems. Chlormequat 2000 ppm and indolylacetic acid 100 ppm reduced plant height and the lenght of the fourth internode of the groundnut plant stem
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