| 1. |
- Alagumalai, Vasudevan, et al.
(author)
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Impact response and damage tolerance of hybrid glass/kevlar-fibre epoxy structural composites
- 2021
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In: Polymers. - : MDPI. - 2073-4360. ; 13:16
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Journal article (peer-reviewed)abstract
- The present study is aimed at investigating the effect of hybridisation on Kevlar/E-Glass based epoxy composite laminate structures. Composites with 4 mm thickness and 16 layers of fibre (14 layers of E-glass centred and 2 outer layers of Kevlar) were fabricated using compression moulding technique. The fibre orientation of the Kevlar layers had 3 variations (0, 45 and 60°), whereas the E-glass fibre layers were maintained at 0° orientation. Tensile, flexural, impact (Charpy and Izod), interlaminar shear strength and ballistic impact tests were conducted. The ballistic test was performed using a gas gun with spherical hard body projectiles at the projectile velocity of 170 m/s. The pre-and post-impact velocities of the projectiles were measured using a high-speed camera. The energy absorbed by the composite laminates was further reported during the ballistic test, and a computerised tomographic scan was used to analyse the impact damage. The composites with 45° fibre orientation of Kevlar fibres showed better tensile strength, flexural strength, Charpy impact strength, and energy absorption. The energy absorbed by the composites with 45° fibre orientation was 58.68 J, which was 14% and 22% higher than the 0° and 60° oriented composites. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
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| 2. |
- Coronel, Edvin, et al.
(author)
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Evaluation of Pearson correlation coefficient and Parisi parameter of replica symmetry breaking in a hybrid electronically addressable random fiber laser
- 2021
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In: Optics Express. - : The Optical Society. - 1094-4087. ; 29:15, s. 24422-24433
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Journal article (peer-reviewed)abstract
- The hybrid electronically addressable random (HEAR) laser is a novel type of random fiber laser that presents the remarkable property of selection of the fiber section with lasing emission. Here we present a joint analysis of the correlations between intensity fluctuations at distinct wavelengths and replica symmetry breaking (RSB) behavior of the HEAR laser. We introduce a modified Pearson coefficient that simultaneously comprises both the Parisi overlap parameter and standard Pearson correlation coefficient. Our results highlight the contrast between the correlations and presence or not of RSB phenomenon in the spontaneous emission behavior well below threshold, replica-symmetric ASE regime slightly below threshold, and RSB phase with random lasing emission above threshold. In particular, in the latter we find that the onset of RSB behavior is accompanied by a stochastic dynamics of the lasing modes, leading to competition for gain intertwined with correlation and anti-correlation between modes in this complex photonic phase.
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| 3. |
- Margulis, Walter, et al.
(author)
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Hybrid electronically addressable random fiber laser
- 2020
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In: Optics Express. - : OSA - The Optical Society. - 1094-4087. ; 28:16, s. 23388-23396
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Journal article (peer-reviewed)abstract
- We report here a novel architecture for a random fiber laser exploiting the combination of a semiconductor optical amplifier (SOA) and an erbium doped fiber (EDF). The EDF was optically biased by a continuous wave pump laser, whereas the SOA was arranged in a fiber loop-mirror and driven by nanosecond duration current pulses. Laser pulses were obtained by synchronizing the SOA driver to the returning amplified Rayleigh back-scattered light from a selected short section of the EDF. By tuning the SOA pulse rate, random lasing was achieved by addressing selected meter-long sections of the 81-m long EDF, which was open-ended. Laser oscillation can be potentially obtained with SOA modulation frequencies from several kHz to the MHz regime. We discuss the mechanism leading to the hybrid random laser emission, connecting with phase sensitive optical time domain reflectometry and envision potential applications of this electronically addressable random laser.
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| 4. |
- Shanmugam, Vigneshwaran, et al.
(author)
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A Review of the Synthesis, Properties, and Applications of 2D Materials
- 2022
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In: Particle & particle systems characterization. - : John Wiley & Sons. - 0934-0866 .- 1521-4117. ; 39:6
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Research review (peer-reviewed)abstract
- In the modern age of nanotechnology, the discovery of graphene has opened up the way to study and develop of several novel 2D materials. The unique physical and chemical properties of 2D materials have enhanced their research, making them superior to the commercial bulk materials used in various applications. Efforts have been made in the current study to present an overview of the intrinsic properties of these materials. Furthermore, synthesis and applications are also reviewed and discussed. Finally, the future outlook of 2D materials is discussed to enhance the research and performance of these materials, which can result in broader applications benefitting the electrical and electronics industries and society. Intensive research into 2D materials is expected to lead to the discovery of new materials with enhanced properties that will benefit the industry and society at large.
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