Hollow core photonic bandgap fibers provide a new geometry for the realization and enhancement of many nonlinear optical effects. Such fibers offer novel guidance and dispersion properties that provide an advantage over conventional fibers for various applications. Dispersion, which expresses the variation with wavelength of the guided-mode group velocity, is one of the most important properties of optical fibers. Photonic crystal fibers (PCFs) offer much larger flexibility than conventional fibers with respect to tailoring of the dispersion curve. This is partly due to the large refractive-index contrast available in the silica/air microstructures, and partly due to the possibility of making complex refractive-index structure over the fiber cross section. In this paper the fundamental physical mechanism has been discussed determining the dispersion properties of PCFs, and the dispersion in a gas filled hollow core photonic crystal fiber has been calculated. We calculate the dispersion of air filled hollow core photonic crystal fiber, also calculate the dispersion of N2 gas filled hollow core photonic crystal fiber and finally we calculate the dispersion of He gas filled hollow core photonic crystal fiber.
A robust and sensitive analytical method is presented for the extraction and determination of six pharmaceuticals in freshwater sediments.
This study explored the use of industrial acidic crude palm oil (ACPO) for biodiesel production, facing a significant obstacle due to its high free fatty acid (FFA) content, which complicates the biodiesel production process. Typically, esterification is employed to convert FFAs into fatty acid methyl ester (FAME). Herein, the effectiveness of tungstosilicic acid hydrate (TSAH) as an unsupported heteropoly acid (HPA) catalyst for FFA esterification in ACPO was investigated. The FFA content was reduced from 8.43% to 0.95% under optimum conditions (4 wt% catalyst dosage, a methanol to oil molar ratio of 10:1, 150 min and a temperature of 60°C). Noteworthy, the TSAH catalyst showed stability over 7
Background/objectives: Inflammatory mediators such as prostaglandin E2 (PGE2) and nitric oxide (NO) are key indicators of pulp response to mechanical trauma. However, the influence of cavity depth on their release dynamics remains unclear. This study aimed to evaluate the effects of different cavity depths—moderate (without pulp exposure) and deep (with pulp exposure)—on the release of PGE2 and NO in the pulp tissue of rat mandibular incisors at two time intervals (3 and 9 h).Methods: In total, 40 male Wistar rats were divided into two main groups (n = 20) based on cavity depth. A split-mouth design was used, with cavities of different depths prepared on the left mandibular incisors, leaving the right incisors without cavities as
... Show MoreLiterary works include, for the most part, text thresholds, which are the first entry into reading them and understanding their connotations, and (literary works) vary according to text thresholds, some of which are limited to the title and on the cover page only, and others, in addition to these two thresholds, are based on the dedication threshold too, and others ...
This study takes the story of "Mamo Zain" of the poet Ahmed Al-Khani and his translator Sheikh Muhammad Ramadan Al-Bouti as the field of study, as it is a unique literary work, which included a number of textual thresholds which supported each other and cooperated with the content of the work.
The threshold of dedication in the story of "Mamo Zain" was a spee
... Show MoreThe exercise of activities and sports are of great importance to public health and to maintain the ideal health weight as well as the psychological and mental comfort of humans. The aim of this study is to determine the contribution and participation of educated females in physical activities at the University of Baghdad hall for the years 2011-2016, and to show the factors that influence women's contribution to physical activities at the university by selecting 100 students of males and 100 females' students randomly. During the questioning questions and statistical analysis of the questioning to find out the reasons for the discouraging contribution of the women to the various physical activities and try to find solutions and r
... Show MoreMixed ligand of Co and Ni (II) complexes were prepared from [5-(p-nitrophenyl)-4/-phenyl-1,2,4-triazole-3-dithiocarbamato hydrazide](TRZ.DTC) as primary ligand and 2,2'-bipyridyl (bipy) as a co-ligand with metal salts. These complexes were analytically and spectroscopically characterized in solid state by elemental analyses, flame atomic absorption, magnetic susceptibility and molar conductance measurements, as well as by UV–Vis and FTIR spectroscopy. Infrared, ultra violet spectra reveal a bidentate coordination of the two ligands with metal ions 1:1:1 mole ratio. Room temperature magnetic moments and solid reflectance spectra data indicate paramagnetic complexes with five-coordinate square pyramidal geometry for nickel (II) comple
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