Search results for: spin glass
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1238

Search results for: spin glass

1028 Optimum Design of Attenuator of Spun-Bond Production System

Authors: Nasser Ghassembaglou, Abdullah Bolek, Oktay Yilmaz, Ertan Oznergiz, Hikmet Kocabas, Safak Yilmaz

Abstract:

Nanofibers are effective material which have frequently been investigated to produce high quality air filters. As an environmental approach our aim is to achieve nanofibers by melting. In spun-bond systems extruder, spin-pump, nozzle package and attenuator are used. Molten polymer which flows from extruder is made steady by spin-pump. Regular melt passes through nozzle holes and forms fibers under high pressure. The fibers pulled from nozzle are shrunk to micron size by an attenuator, after solidification they are collected on a conveyor. In this research different designs of attenuator system have been studied and also CFD analysis have been done on them. Afterwards, one of these designs tested and finally some optimizations have been done to reduce pressure loss and increase air velocity.

Keywords: attenuator, nanofiber, spun-bond, extruder

Procedia PDF Downloads 386
1027 Stern-Gerlach Force in Quantum Magnetic Field and Schrodinger's Cat

Authors: Mandip Singh

Abstract:

Quantum entanglement plays a fundamental role in our understanding of counter-intuitive aspects of quantum reality. If classical physics is an approximation of quantum physics, then quantum entanglement should persist at a macroscopic scale. In this paper, a thought experiment is presented where a free falling spin polarized Bose-Einstein condensate interacts with a quantum superimposed magnetic field of nonzero gradient. In contrast to the semiclassical Stern-Gerlach experiment, the magnetic field and the spin degrees of freedom both are considered to be quantum mechanical in a generalized scenario. As a consequence, a Bose-Einstein condensate can be prepared at distinct locations in space in a sense of quantum superposition. In addition, the generation of Schrodinger-cat like quantum states shall be presented.

Keywords: Schrodinger-cat quantum states, macroscopic entanglement, macroscopic quantum fields, foundations of quantum physics

Procedia PDF Downloads 157
1026 Scientific and Technical Basis for the Application of Textile Structures in Glass Using Pate De Verre Technique

Authors: Walaa Hamed Mohamed Hamza

Abstract:

Textile structures are the way in which the threading process of both thread and loom is done together to form the woven. Different methods of attaching the clothing and the flesh produce different textile structures, which differ in their surface appearance from each other, including so-called simple textile structures. Textile compositions are the basis of woven fabric, through which aesthetic values can be achieved in the textile industry by weaving threads of yarn with the weft at varying degrees that may reach the total control of one of the two groups on the other. Hence the idea of how art and design can be used using different textile structures under the modern techniques of pate de verre. In the creation of designs suitable for glass products employed in the interior architecture. The problem of research: The textile structures, in general, have a significant impact on the appearance of the fabrics in terms of form and aesthetic. How can we benefit from the characteristics of different textile compositions in different glass designs with different artistic values. The research achieves its goal by the investment of simple textile structures in innovative artistic designs using the pate de verre technique, as well as the use of designs resulting from the textile structures in the external architecture to add various aesthetic values. The importance of research in the revival of heritage using ancient techniques, as well as synergy between different fields of applied arts such as glass and textile, and also study the different and diverse effects resulting from each fabric composition and the possibility of use in various designs in the interior architecture. The research will be achieved that by investing in simple textile compositions, innovative artistic designs produced using pate de verre technology can be used in interior architecture.

Keywords: glass, interior architecture, pate de verre, textile structures

Procedia PDF Downloads 257
1025 Theoretical Study of Electronic Structure of Erbium (Er), Fermium (Fm), and Nobelium (No)

Authors: Saleh O. Allehabi, V. A. Dzubaa, V. V. Flambaum, Jiguang Li, A. V. Afanasjev, S. E. Agbemava

Abstract:

Recently developed versions of the configuration method for open shells, configuration interaction with perturbation theory (CIPT), and configuration interaction with many-body perturbation theory (CI+MBPT) techniques are used to study the electronic structure of Er, Fm, and No atoms. Excitation energies of odd states connected to the even ground state by electric dipole transitions, the corresponding transition rates, isotope shift, hyperfine structure, ionization potentials, and static scalar polarizabilities are calculated. The way of extracting parameters of nuclear charge distribution beyond nuclear root mean square (RMS) radius, e.g., a parameter of quadrupole deformation β, is demonstrated. In nuclei with spin > 1/2, parameter β is extracted from the quadrupole hyperfine structure. With zero nuclear spin or spin 1/2, it is impossible since quadrupole zero, so a different method was developed. The measurements of at least two atomic transitions are needed to disentangle the contributions of the changes in deformation and nuclear RMS radius into field isotopic shift. This is important for testing nuclear theory and for searching for the hypothetical island of stability. Fm and No are heavy elements approaching the superheavy region, for which the experimental data are very poor, only seven lines for the Fm element and one line for the No element. Since Er and Fm have similar electronic structures, calculations for Er serve as a guide to the accuracy of the calculations. Twenty-eight new levels of Fm atom are reported.

Keywords: atomic spectra, electronic transitions, isotope effect, electron correlation calculations for atoms

Procedia PDF Downloads 129
1024 Development of a Microfluidic Device for Low-Volume Sample Lysis

Authors: Abbas Ali Husseini, Ali Mohammad Yazdani, Fatemeh Ghadiri, Alper Şişman

Abstract:

We developed a microchip device that uses surface acoustic waves for rapid lysis of low level of cell samples. The device incorporates sharp-edge glass microparticles for improved performance. We optimized the lysis conditions for high efficiency and evaluated the device's feasibility for point-of-care applications. The microchip contains a 13-finger pair interdigital transducer with a 30-degree focused angle. It generates high-intensity acoustic beams that converge 6 mm away. The microchip operates at a frequency of 16 MHz, exciting Rayleigh waves with a 250 µm wavelength on the LiNbO3 substrate. Cell lysis occurs when Candida albicans cells and glass particles are placed within the focal area. The high-intensity surface acoustic waves induce centrifugal forces on the cells and glass particles, resulting in cell lysis through lateral forces from the sharp-edge glass particles. We conducted 42 pilot cell lysis experiments to optimize the surface acoustic wave-induced streaming. We varied electrical power, droplet volume, glass particle size, concentration, and lysis time. A regression machine-learning model determined the impact of each parameter on lysis efficiency. Based on these findings, we predicted optimal conditions: electrical signal of 2.5 W, sample volume of 20 µl, glass particle size below 10 µm, concentration of 0.2 µg, and a 5-minute lysis period. Downstream analysis successfully amplified a DNA target fragment directly from the lysate. The study presents an efficient microchip-based cell lysis method employing acoustic streaming and microparticle collisions within microdroplets. Integration of a surface acoustic wave-based lysis chip with an isothermal amplification method enables swift point-of-care applications.

Keywords: cell lysis, surface acoustic wave, micro-glass particle, droplet

Procedia PDF Downloads 52
1023 Effects of CFRP Confinement on PCC and Glass Fiber Reinforced Concrete

Authors: Muhammad Jahangeer Munir, Liaqat Ali Qureshi, Junaid Ahmed

Abstract:

This paper presents the investigation regarding use of glass fibers in structural concrete members and determining the behavior of normal PCC, GFRC and retrofitted GFRC under different tests performed in the laboratory. Effect of retrofitting on the GFRC & PCC was investigated by using three patterns of CFRP wrapping. Properties like compressive, split tensile and flexural strength of normal GFRC and retrofitted GFRC were investigated and compared with their PCC counterparts. It was found that GFRC has more compressive strength as compared to PCC. At lower confinement pressures PCC behaves better than GFRC. Confinement efficiency was lower in GFRC as compared to PCC in terms of Split tensile strength. In case of GFRC all the patterns of wrapped CFRP strips showed more strength than their PCC counterparts.

Keywords: carbon fiber reinforced polymers, confinement, glass fibers, retrofitting

Procedia PDF Downloads 568
1022 Complete Enumeration Approach for Calculation of Residual Entropy for Diluted Spin Ice

Authors: Yuriy A. Shevchenko, Konstantin V. Nefedev

Abstract:

We consider the antiferromagnetic systems of Ising spins located at the sites of the hexagonal, triangular and pyrochlore lattices. Such systems can be diluted to a certain concentration level by randomly replacing the magnetic spins with nonmagnetic ones. Quite recently we studied density of states (DOS) was calculated by the Wang-Landau method. Based on the obtained data, we calculated the dependence of the residual entropy (entropy at a temperature tending to zero) on the dilution concentration for quite large systems (more than 2000 spins). In the current study, we obtained the same data for small systems (less than 20 spins) by a complete search of all possible magnetic configurations and compared the result with the result for large systems. The shape of the curve remains unchanged in both cases, but the specific values of the residual entropy are different because of the finite size effect.

Keywords: entropy, pyrochlore, spin ice, Wang-Landau algorithm

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1021 Experimental and Numerical Investigations of Impact Response on High-Speed Train Windshield

Authors: Wen Ma, Yong Peng, Zhixiang Li

Abstract:

Security journey is a vital focus on the field of Rail Transportation. Accidents caused by the damage of the high-speed train windshield have occurred many times and have given rise to terrible consequences. Train windshield consists of tempered glass and polyvinyl butyral (PVB) film. In this work, the quasi-static tests and the split Hopkinson pressure bar (SHPB) tests were carried out first to obtain the mechanical properties and constitutive model for the tempered glass and PVB film. These tests results revealed that stress and Young’s modulus of tempered glass were wake-sensitive to strain rate, but stress and Young’s modulus of PVB film were strong-sensitive to strain rate. Then impact experiment of the windshield was carried out to investigate dynamic response and failure characteristics of train windshield. In addition, a finite element model based on the combined finite element method was proposed to investigate fracture and fragmentation responses of train windshield under different-velocity impact. The results can be used for further design and optimization of the windshield for high-speed train application.

Keywords: constitutive model, impact response, mechanism properties, PVB film, tempered glass

Procedia PDF Downloads 122
1020 A Simple Chemical Approach to Regenerating Strength of Thermally Recycled Glass Fibre

Authors: Sairah Bashir, Liu Yang, John Liggat, James Thomason

Abstract:

Glass fibre is currently used as reinforcement in over 90% of all fibre-reinforced composites produced. The high rigidity and chemical resistance of these composites are required for optimum performance but unfortunately results in poor recyclability; when such materials are no longer fit for purpose, they are frequently deposited in landfill sites. Recycling technologies, for example, thermal treatment, can be employed to address this issue; temperatures typically between 450 and 600 °C are required to allow degradation of the rigid polymeric matrix and subsequent extraction of fibrous reinforcement. However, due to the severe thermal conditions utilised in the recycling procedure, glass fibres become too weak for reprocessing in second-life composite materials. In addition, more stringent legislation is being put in place regarding disposal of composite waste, and so it is becoming increasingly important to develop long-term recycling solutions for such materials. In particular, the development of a cost-effective method to regenerate strength of thermally recycled glass fibres will have a positive environmental effect as a reduced volume of composite material will be destined for landfill. This research study has demonstrated the positive impact of sodium hydroxide (NaOH) and potassium hydroxide (KOH) solution, prepared at relatively mild temperatures and at concentrations of 1.5 M and above, on the strength of heat-treated glass fibres. As a result, alkaline treatments can potentially be implemented to glass fibres that are recycled from composite waste to allow their reuse in second-life materials. The optimisation of the strength recovery process is being conducted by varying certain reaction parameters such as molarity of alkaline solution and treatment time. It is believed that deep V-shaped surface flaws exist commonly on severely damaged fibre surfaces and are effectively removed to form smooth, U-shaped structures following alkaline treatment. Although these surface flaws are believed to be present on glass fibres they have not in fact been observed, however, they have recently been discovered in this research investigation through analytical techniques such as AFM (atomic force microscopy) and SEM (scanning electron microscopy). Reaction conditions such as molarity of alkaline solution affect the degree of etching of the glass fibre surface, and therefore the extent to which fibre strength is recovered. A novel method in determining the etching rate of glass fibres after alkaline treatment has been developed, and the data acquired can be correlated with strength. By varying reaction conditions such as alkaline solution temperature and molarity, the activation energy of the glass etching process and the reaction order can be calculated respectively. The promising results obtained from NaOH and KOH treatments have opened an exciting route to strength regeneration of thermally recycled glass fibres, and the optimisation of the alkaline treatment process is being continued in order to produce recycled fibres with properties that match original glass fibre products. The reuse of such glass filaments indicates that closed-loop recycling of glass fibre reinforced composite (GFRC) waste can be achieved. In fact, the development of a closed-loop recycling process for GFRC waste is already underway in this research study.

Keywords: glass fibers, glass strengthening, glass structure and properties, surface reactions and corrosion

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1019 Study of The Ballistic Impact at Low Speed on Angle-Ply Fibrous Structures

Authors: Daniel Barros, Carlos Mota, Raul Fangueiro, Pedro Rosa, Gonçalo Domingos, Alfredo Passanha, Norberto Almeida

Abstract:

The main aim of the work was to compare the ballistic performance of developed composites using different types of fiber woven fabrics [0,90] and different layers orientation (Angle-ply). The ballistic laminate composites were developed using E-glass, S-glass and aramid fabrics impregnated with thermosetting epoxy resin and using different layers orientation (0,0)º and (0,15)º. The idea of the study is to compare the ballistic performance of each laminate produced by studying the velocity loss of the fragment fired into the laminate surface. There are present some mechanical properties for laminates produced using the different types of fiber, where tensile, flexural and impact Charpy properties were studied. Overall, the angle-ply laminates produced using orientations of (0,15)º, despite the slight loss of mechanical properties compared to the (0,0)º orientation, presents better ballistic resistance and dissipation of energy, for lower ballistic impact velocities (under 290 m/s-1). After treatment of ballistic impact results, the S-Glass with (0,15)º laminate presents better ballistic perforce compared to the other combinations studied.

Keywords: ballistic impact, angle-ply, ballistic composite, s-glass fiber, aramid fiber, fabric fiber, energy dissipation, mechanical performance

Procedia PDF Downloads 178
1018 Comparison of Surface Hardness of Filling Material Glass Ionomer Cement Which Soaked in Alcohol Containing Mouthwash and Alcohol-Free Mouthwash

Authors: Farid Yuristiawan, Aulina R. Rahmi, Detty Iryani, Gunawan

Abstract:

Glass ionomer cement is one of the filling material that often used in the field of dentistry because it is relatively less expensive and mostly available. Surface hardness is one of the most important properties of restoration material; it is the ability of material to stand against indentation, which is directly connected to the material compressive strength and its ability to withstand abrasion. The higher surface hardness of a material means it is better to withstand abrasion. The existence of glass ionomer cement in the mouth makes it susceptible to any substance that comes into mouth, one of them is mouthwash which is a solution that used for many purposes such as antiseptic, astringent, to prevent caries, and bad breath. The presence of alcohol in mouthwash could affect the properties of glass ionomer cement, surface hardness. Objective: To determine the comparison of surface hardness of glass ionomer cement which soaked in alcohol containing mouthwash and alcohol-free mouthwash. Methods: This research is a laboratory experimental type study. There were 30 samples made from GC FUJI IX GP EXTRA and then soaked in artificial saliva for the first 24 hours inside incubator which temperature and humidity were controlled. Samples then divided into three groups. The first group will be soaked in alcohol-containing mouthwash; second group will be soaked alcohol-free mouthwash and control group will be soaked in artificial saliva for 6 hours inside incubator. Listerine is the mouthwash that was used on this research and surface hardness was examined using Vickers Hardness Tester. The result of this research shows mean value for surface hardness of the first group is 16.36 VHN, 24.04 VHN for second group, and 43.60 VHN for control group. The result one way ANOVA with post hoc Bonferroni comparing test show significant results p = 0.00. Conclusions: The data showed there were statistically significant differences of surface hardness between each group, which surface hardness of the first group is lower than the second group, and both surface hardness of the first (alcohol mouthwash) and second group (alcohol-free mouthwash) are lowered than control group (p = 0.00).

Keywords: glass ionomer cement, mouthwash, surface hardness, Vickers hardness tester

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1017 Exploring Spin Reorientation Transition and Berry Curvature Driven Anomalous Hall Effect in Quasi-2D vdW Ferromagnet Fe4GeTe2

Authors: Satyabrata Bera, Mintu Mondal

Abstract:

Two-dimensional (2D) ferromagnetic materials have garnered significant attention due to their potential to host intriguing scientific phenomena such as the anomalous Hall effect, anomalous Nernst effect, and high transport spin polarization. This study focuses on the investigation of air-stable van der Waals(vdW) ferromagnets, FeGeTe₂ (FₙGT with n = 3, 4, and 5). Particular emphasis is placed on the Fe4GeTe2 (F4GT) compound, which exhibits a complex and fascinating magnetic behavior characterized by two distinct transitions: (i) paramagnetic (PM) to ferromagnetic (FM) around T C ∼ 270 K, and (ii) another spins reorientation transition (SRT) at T SRT ∼ 100 K . Scaling analysis of magnetocaloric effect confirms the second-order character of the ferromagnetic transition, while the same analysis at T SRT suggests that SRT is first-order phase transition. Moreover, the F4GT exhibits a large anomalous Hall conductivity (AHC), ∼ 490 S/cm at 2 K . The near-quadratic behavior of the anomalous Hall resistivity with the longitudinal resistivity suggests that a dominant AHC contribution arises from an intrinsic Berry curvature (BC) mechanism. Electronic structure calculations reveal a significant BC resulting from SOC-induced gapped nodal lines around the Fermi level, thereby giving rise to large AHC. Additionally, we reported exceptionally large anomalous Hall angle (≃ 10.6%) and Hall factor (≃ 0.22 V −1 ) values, the largest observed within this vdW family. The findings presented here, provide valuable insights into the fascinating magnetic and transport properties of 2D ferromagnetic materials, in particular, FₙGT family.

Keywords: 2D vdW ferromagnet, spin reorientation transition, anomalous hall effect, berry curvature

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1016 Behaviour of Non-local Correlations and Quantum Information Theoretic Measures in Frustrated Molecular Wheels

Authors: Amit Tribedi

Abstract:

Genuine Quantumness present in Quantum Systems is the resource for implementing Quantum Information and Computation Protocols which can outperform the classical counterparts. These Quantumness measures encompass non-local ones known as quantum entanglement (QE) and quantum information theoretic (QIT) ones, e.g. Quantum Discord (QD). In this paper, some well-known measures of QE and QD in some wheel-like frustrated molecular magnetic systems have been studied. One of the systems has already been synthesized using coordination chemistry, and the other is hypothetical, where the dominant interaction is the spin-spin exchange interaction. Exact analytical methods and exact numerical diagonalization methods have been used. Some counter-intuitive non-trivial features, like non-monotonicity of quantum correlations with temperature, persistence of multipartite entanglement over bipartite ones etc. indicated by the behaviour of the correlations and the QIT measures have been found. The measures, being operational ones, can be used to realize the resource of Quantumness in experiments.

Keywords: 0D Magnets, discord, entanglement, frustration

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1015 Investigation Particle Behavior in Gas-Solid Filtration with Electrostatic Discharge in a Hybrid System

Authors: Flávia M. Oliveira, Marcos V. Rodrigues, Mônica L. Aguiar

Abstract:

Synthetic fibers are widely used in gas filtration. Previous attempts to optimize the filtration process have employed mixed fibers as the filter medium in gas-solid separation. Some of the materials most frequently used this purpose are composed of polyester, polypropylene, and glass fibers. In order to improve the retention of cement particles in bag filters, the present study investigates the use of synthetic glass fiber filters and polypropylene fiber for particle filtration, with electrostatic discharge of 0 to -2 kV in cement particles. The filtration curves obtained showed that charging increased the particle collection efficiency and lowered the pressure drop. Particle diameter had a direct influence on the formation of the dust cake, and the application of electrostatic discharge to the particles resulted in the retention of more particles, hence increasing the lifetime of fabric filters.

Keywords: glass fiber filter, particle, electrostatic discharge, cement

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1014 Analysis of Stress Concentration of a Hybrid Composite Material with Centre Circular Hole Subjected to Tensile Loading

Authors: C. Shalini Devi

Abstract:

This work describes the stress concentration in a rectangular specimen with a circular hole made up of hybrid composite material with the combination of glass/carbon with epoxy. The arrangements of cross ply lamina in the sequence of alternative carbon and glass, using carbon fiber in panel, gives more strength to the structure as the carbon properties are higher when compared to glass. Typical aircraft and automobile components are with cut-outs, and such cut-outs reduce the weight of the aircraft according to the weight reduction law and also they reduce the bulking load carrying capacity. Experimental investigations were carried out using three specimens as per ASTM D5766 and three specimens as per ASTM D3039 in the Universal Testing Machine. Stress concentration in the rectangular specimen with a hole is also analysed using FEA and comparing the results.

Keywords: composite, stress concentration, finite element analysis, tensile strength

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1013 Research on Ice Fixed-Abrasive Polishing Mechanism and Technology for High-Definition Display Panel Glass

Authors: Y. L. Sun, L. Shao, Y. Zhao, H. X. Zhou, W. Z. Lu, J. Li, D. W. Zuo

Abstract:

This study introduces an ice fixed-abrasive polishing (IFAP) technology. Using silica solution IFAP pad and Al2O3 IFAP pad, orthogonal tests were performed on polishing high-definition display panel glass, respectively. The results show that the polishing efficiency and effect polished with silica solution IFAP pad are better than those polished with Al2O3 IFAP pad. The optimized silica solution IFAP parameters are: polishing pressure 0.1MPa, polishing time 40min, table velocity 80r/min, and the ratio of accelerator and slurry 1:10. Finally, the IFAP mechanism was studied and it suggests by complicated analysis that IFAP is comprehensive effect of mechanical removal and microchemical reaction, combined with fixed abrasive polishing and free abrasive polishing.

Keywords: ice fixed-abrasive polishing, high-definition display panel glass, material removal rate, surface roughness

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1012 Room Temperature Electron Spin Resonance and Raman Study of Nanocrystalline Zn(1-x)Cu(x)O (0.005 < x < 0.05) Synthesized by Pyrophoric Method

Authors: Jayashree Das, V. V. Srinivasu , D. K. Mishra, A. Maity

Abstract:

Owing to the important potential applications over decades, transition metal (TM: Mn, Fe, Ni, Cu, Cr, V etc.) doped ZnO-based diluted magnetic semiconductors (DMS) always attract research attention for more and newer investigations. One of the interesting aspects of these materials is to study and understand the magnetic property at room temperature properly, which is very crucial to select a material for any related application. In this regard, Electron spin resonance (ESR) study has been proven to be a powerful technique to investigate the spin dynamics of electrons inside the system, which are responsible for the magnetic behaviour of any system. ESR as well as the Raman and Photoluminescence spectroscopy studies are also helpful to study the defects present or created inside the system in the form of oxygen vacancy or cluster instrumental in determining the room temperature ferromagnetic property of transition metal doped ZnO system, which can be controlled through varying dopant concentration, appropriate synthesis technique and sintering of the samples. For our investigation, we synthesised Cu-doped ZnO nanocrystalline samples with composition Zn1-xCux ( 0.005< x < 0.05) by pyrophoric method and sintered at a low temperature of 650 0C. The microwave absorption is studied by the Electron Spin Resonance (ESR) of X-band (9.46 GHz) at room temperature. Systematic analysis of the obtained ESR spectra reveals that all the compositions of Cu-doped ZnO samples exhibit resonance signals of appreciable line widths and g value ~ 2.2, typical characteristic of ferromagnetism in the sample. Raman scattering and the photoluminescence study performed on the samples clearly indicated the presence of pronounced defect related peaks in the respective spectra. Cu doping in ZnO with varying concentration also observed to affect the optical band gap and the respective absorption edges in the UV-Vis spectra. FTIR spectroscopy reveals the Cu doping effect on the stretching bonds of ZnO. To probe into the structural and morphological changes incurred by Cu doping, we have performed XRD, SEM and EDX study, which confirms adequate Cu substitution without any significant impurity phase formation or lattice disorder. With proper explanation, we attempt to correlate the results observed for the structural optical and magnetic behaviour of the Cu-doped ZnO samples. We also claim that our result can be instrumental for appropriate applications of transition metal doped ZnO based DMS in the field of optoelectronics and Spintronics.

Keywords: diluted magnetic semiconductors, electron spin resonance, raman scattering, spintronics.

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1011 Ordinary and Triplet Superconducting Spin Valve Effect in Fe/Pb Based Heterostructures

Authors: P. V. Leksin, A. A. Kamashev, N. N. Garifyanov, I. A. Garifullin, Ya. V. Fominov, J. Schumann, Y. Krupskaya, V. Kataev, O. G. Schmidt, B. Büchner

Abstract:

We report on experimental evidence for the occurrence of the long range triplet correlations (LRTC) of the superconducting (SC) condensate in the spin-valve heterostructures CoOx/Fe1/Cu/Fe2/Pb. The LRTC generation in this layer sequence is accompanied by a Tc suppression near the orthogonal mutual orientation of the Fe1 and Fe2 layers’ magnetization. This Tc drop reaches its maximum of 60mK at the Fe2 layer thickness dFe2 = 0.6 nm and falls down when dFe2 is increased. The modification of the Fe/Pb interface by using a thin Cu intermediate layer between Fe and Pb layers reduces the SC transition width without preventing the interaction between Pb and Fe2 layers. The dependence of the SSVE magnitude on Fe1 layer thickness dFe1 reveals maximum of the effect when dFe1 and dFe2 are equal and the dFe2 value is minimal. Using the optimal Fe layers thicknesses and the intermediate Cu layer between Pb and Fe2 layer we realized almost full switching from normal to superconducting state due to SSVE.

Keywords: superconductivity, ferromagnetism, heterostructures, proximity effect

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1010 Death Due to Ulnar Artery Injury by Glassdoor: A Case Report

Authors: Ashok Kumar Rastogi

Abstract:

Glass is a material commonly used for Glassdoor, glass bottles, cookware, and containers. It can be harmful, as it is a hard and blunt object. Glass has been associated with severe injury and is a common cause of injuries warranting hospital visits to the emergency department (ED). These injuries can be accidental or intentionally inflicted. Broken glass injuries can be severe, even deadly. If broken glass shards fall out on your arm, it may cause fatal injuries. Case history: A 20-year-old male dead body was found aside the road, police informed, and a video recording ceased during an investigation. In the video recording, the person was in a drunken state (unable to walk and disoriented), wandering in the residential area road. He saw a barber shop, the shop door made of Glass. Suddenly, he hit the Glassdoor with his right hand forcefully. The Glassdoor broke into multiple pieces, and multiple injuries were seen over the right hand. Observations: Multiple small and large lacerations were seen over the right anterior part of the elbow. The main injury looked like an incised wound caused by a hard and sharp object. The main injury was noted as a laceration of size 13 x 06 cm bone deep, placed obliquely over the anteromedial aspect of the right elbow joint, its medial end at medial end of elbow joint while its anterior end was 04 cm below the elbow joint with laceration of underline brachialis muscles and complete transaction of ulnar artery and vein, skin margins looking sharply cut with irregular margins with tiny cuts at the medial lower border of laceration. Injuries were antemortem and fresh in nature, caused by hard and blunt objects but looking like hard and sharp objects. All organs were found pale, and the cause of death was shock and hemorrhage because of ulnar vessel injury. Conclusion: The findings of this case report highlight the potentially lethal consequences of glass injuries, especially those involving Glassdoors. The study underscores the importance of accurate interpretation and identification of wounds caused by Glass, as they may resemble injuries caused by other objects. It emphasizes the challenges faced by autopsy surgeons when determining the cause and manner of death in cases where visual evidence of injury is absent or when the weapon is not recovered. Ultimately, this case report serves as a reminder of the potential dangers posed by Glass and the importance of comprehensive forensic examinations.

Keywords: glassdoor, incised, wound, laceration, autopsy

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1009 Anti-Reflective Nanostructured TiO2/SiO2 Multilayer Coatings

Authors: Najme lari, Shahrokh Ahangarani, Ali Shanaghi

Abstract:

Multilayer structure of thin films by the sol–gel process attracts great attention for antireflection applications. In this paper, antireflective nanometric multilayer SiO2-TiO2 films are formed on both sides of the glass substrates by combining the sol–gel method and the dip-coating technique. SiO2 and TiO2 sols were prepared using tetraethylorthosilicate (TEOS) and tetrabutylorthotitanate (TBOT) as precursors and also nitric acid as catalyst. Prepared coatings were investigated by Field-emission scanning electron microscope (FE-SEM), Fourier-transformed infrared spectrophotometer (FT-IR) and UV–visible spectrophotometer. After evaluation, all of SiO2 top layer coatings showed excellent antireflection in the wavelength range of 400-800 nm where the transmittance of glass substrate is significantly lower. By increasing the number of double TiO2-SiO2 layers, the transmission of the coated glass increases due to applied multilayer coating properties. 6-layer sol–gel TiO2-SiO2 shows the highest visible transmittance about 99.25% at the band of 550-650 nm.

Keywords: thin films, optical properties, sol-gel, multilayer

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1008 Static Relaxation of Glass Fiber Reinforced Pipes

Authors: Mohammed Y. Abdellah, Mohamed K. Hassan, A. F. Mohamed, Shadi M. Munshi, A. M. Hashem

Abstract:

Pips made from glass fiber reinforced polymer has competitive role in petroleum industry. The need of evaluating the mechanical behavior of (GRP) pipes is essential objects. Stress relaxation illustrates how polymers relieve stress under constant strain. Static relaxation test is carried out at room temperature. The material gives poor static relaxation strength, two loading cycles have been observed for the tested specimen.

Keywords: GRP, sandwich composite material, static relaxation, stress relief

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1007 Sol-Gel SiO2-TiO2 Multilayer Coatings for Anti-Reflective Applications

Authors: Najme Lari, Shahrokh Ahangarani, Ali Shanaghi

Abstract:

Multilayer structure of thin films by the sol–gel process attracts great attention for antireflection applications. In this paper, antireflective nanometric multilayer SiO2-TiO2 films are formed on both sides of the glass substrates by combining the sol–gel method and the dip-coating technique. SiO2 and TiO2 sols were prepared using tetraethylorthosilicate (TEOS) and tetrabutylorthotitanate (TBOT) as precursors and nitric acid as catalyst. Prepared coatings were investigated by Field-emission scanning electron microscope (FE-SEM), Fourier-transformed infrared spectrophotometer (FT-IR) and UV–visible spectrophotometer. After evaluation, all of SiO2 top layer coatings showed excellent antireflection in the wavelength range of 400-800 nm where the transmittance of glass substrate is significantly lower. By increasing the number of double TiO2-SiO2 layers, the transmission of the coated glass increases due to applied multilayer coating properties. 6-layer sol–gel TiO2-SiO2 shows the highest visible transmittance about 99.25% at the band of 550-650 nm.

Keywords: thin films, optical properties, sol-gel, multilayer

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1006 An Investigation into Sealing Materials for Vacuum Glazing

Authors: Paul Onyegbule, Harjit Singh

Abstract:

Vacuum glazing is an innovative transparent thermal insulator that has application in high performance window, especially in renewable energy. Different materials as well as sealing methods have been adopted to seal windows with different temperatures. The impact of temperatures on sealing layers has been found to have significant effects on the microstructure of the seal. This paper seeks to investigate the effects of sealing materials specifically glass powder and flux compound (borax) for vacuum glazing. The findings of the experiment conducted show that the sealing material was rigid with some leakage around the edge, and we found that this could be stopped by enhancing the uniformity of the seal within the periphery. Also, we found that due to the intense tensile stress from the oven surface temperature of the seal at 200 0C, a crack was observed at the side of the glass. Based on the above findings, this study concludes that a glass powder with a lower melting temperature of below 250 0C with the addition of an adhesive (borax flux) should be used for future vacuum seals.

Keywords: double glazed windows, U-value, heat loss, borax powder, edge seal

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1005 Improving Productivity in a Glass Production Line through Applying Principles of Total Productive Maintenance (TPM)

Authors: Omar Bataineh

Abstract:

Total productive maintenance (TPM) is a principle-based method that aims to get a high-level production with no breakdowns, no slow running and no defects. Key principles of TPM were applied in this work to improve the performance of the glass production line at United Beverage Company in Kuwait, which is producing bottles of soft drinks. Principles such as 5S as a foundation for TPM implementation, developing a program for equipment management, Cause and Effect Analysis (CEA), quality improvement, training and education of employees were employed. After the completion of TPM implementation, it was possible to increase the Overall Equipment Effectiveness (OEE) from 23% to 40%.

Keywords: OEE, TPM, FMEA, CEA

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1004 Silicon-To-Silicon Anodic Bonding via Intermediate Borosilicate Layer for Passive Flow Control Valves

Authors: Luc Conti, Dimitry Dumont-Fillon, Harald van Lintel, Eric Chappel

Abstract:

Flow control valves comprise a silicon flexible membrane that deflects against a substrate, usually made of glass, containing pillars, an outlet hole, and anti-stiction features. However, there is a strong interest in using silicon instead of glass as substrate material, as it would simplify the process flow by allowing the use of well controlled anisotropic etching. Moreover, specific devices demanding a bending of the substrate would also benefit from the inherent outstanding mechanical strength of monocrystalline silicon. Unfortunately, direct Si-Si bonding is not easily achieved with highly structured wafers since residual stress may prevent the good adhesion between wafers. Using a thermoplastic polymer, such as parylene, as intermediate layer is not well adapted to this design as the wafer-to-wafer alignment is critical. An alternative anodic bonding method using an intermediate borosilicate layer has been successfully tested. This layer has been deposited onto the silicon substrate. The bonding recipe has been adapted to account for the presence of the SOI buried oxide and intermediate glass layer in order not to exceed the breakdown voltage. Flow control valves dedicated to infusion of viscous fluids at very high pressure have been made and characterized. The results are compared to previous data obtained using the standard anodic bonding method.

Keywords: anodic bonding, evaporated glass, flow control valve, drug delivery

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1003 Symmetry-Protected Dirac Semi-Metallic Phases in Transition Metal Dichalcogenides

Authors: Mohammad Saeed Bahramy

Abstract:

Transition metal dichalcogenides have experienced a resurgence of interest in the past few years owing to their rich properties, ranging from metals and superconductors to strongly spin-orbit-coupled semiconductors and charge-density-wave systems. In all these cases, the transition metal d-electrons mainly determine the ground state properties. This presentation focuses on the chalcogen-derived states. Combining density-functional theory calculations with spin- and angle-resolved photoemission, it is shown that these states generically host a coexistence of type I and type II three-dimensional bulk Dirac fermions as well as ladders of topological surface states and surface resonances. It will be discussed how these naturally arise within a single p-orbital manifold as a general consequence of a trigonal crystal field, and as such can be expected across many compounds. Our finding opens a new route to design topological materials with advanced functionalities.

Keywords: topology, electronic structure, Dirac semimetals, transition metal dichalcogenides

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1002 Production of Composite Materials by Mixing Chromium-Rich Ash and Soda-Lime Glass Powder: Mechanical Properties and Microstructure

Authors: Savvas Varitis, Panagiotis Kavouras, George Vourlias, Eleni Pavlidou, Theodoros Karakostas, Philomela Komninou

Abstract:

A chromium-loaded ash originating from incineration of tannery sludge under anoxic conditions was mixed with low grade soda-lime glass powder coming from commercial glass bottles. The relative weight proportions of ash over glass powder tested were 30/70, 40/60 and 50/50. The solid mixtures, formed in green state compacts, were sintered at the temperature range of 800oC up to 1200oC. The resulting products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDXS) and micro-indentation. The above methods were employed to characterize the various phases, microstructure and hardness of the produced materials. Thermal treatment at 800oC and 1000oC produced opaque ceramic products composed of a variety of chromium-containing and chromium-free crystalline phases. Thermal treatment at 1200oC gave rise to composite products, where only chromium-containing crystalline phases were detected. Hardness results suggest that specific products are serious candidates for structural applications. Acknowledgement: This research has been co-financed by the European Union (European Social Fund – ESF) and Greek national funds through the Operational Program “Education and Lifelong Learning” of the National Strategic Reference Framework (NSRF) – Research Funding Program: THALES “WasteVal”: Reinforcement of the interdisciplinary and/or inter-institutional research and innovation.

Keywords: chromium-rich tannery residues, glass-ceramic materials, mechanical properties, microstructure

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1001 Effect of Non-Crimp Fabric Structure on Mechanical Properties of Laminates

Authors: Hireni R. Mankodi, D. J. Chudasama

Abstract:

The textile preforms play a key role in providing the mechanical properties and gives the idea about selection parameter of preforms to improve the quality and performance of laminates. The main objectives of this work are to study the effect of non-crimp fabric preform structure in final properties of laminates. It has been observed that the multi-axial preform give better mechanical properties of laminates as compared to woven and biaxial fabrics. This study investigated the effect of different non-crimp glass preform structure on tensile strength, bending and compression properties of glass laminates. The different woven, bi-axial and multi-axial fabrics with similar GSM used to manufacture the laminates using polyester resin. The structural and mechanical properties of preform and laminates were studied using standard methods. It has been observed that the glass fabric geometry, including type of weaves, warps and filling density and number of layer plays significant role in deciding mechanical properties of laminates.

Keywords: preform, non-crimp structure, laminates, bi-axial, multiaxial

Procedia PDF Downloads 465
1000 Mechanical Tests and Analyzes of Behaviors of High-Performance of Polyester Resins Reinforced With Unifilo Fiberglass

Authors: Băilă Diana Irinel, Păcurar Răzvan, Păcurar Ancuța

Abstract:

In the last years, composite materials are increasingly used in automotive, aeronautic, aerospace, construction applications. Composite materials have been used in aerospace in applications such as engine blades, brackets, interiors, nacelles, propellers/rotors, single aisle wings, wide body wings. The fields of use of composite materials have multiplied with the improvement of material properties, such as stability and adaptation to the environment, mechanical tests, wear resistance, moisture resistance, etc. The composite materials are classified concerning type of matrix materials, as metallic, polymeric and ceramic based composites and are grouped according to the reinforcement type as fibre, obtaining particulate and laminate composites. Production of a better material is made more likely by combining two or more materials with complementary properties. The best combination of strength and ductility may be accomplished in solids that consist of fibres embedded in a host material. Polyester is a suitable component for composite materials, as it adheres so readily to the particles, sheets, or fibres of the other components. The important properties of the reinforcing fibres are their high strength and high modulus of elasticity. For applications, as in automotive or in aeronautical domain, in which a high strength-to-weight ratio is important, non-metallic fibres such as fiberglass have a distinct advantage because of their low density. In general, the glass fibres content varied between 9 to 33% wt. in the composites. In this article, high-performance types of composite materials glass-epoxy and glass-polyester used in automotive domain will be analyzed, performing tensile and flexural tests and SEM analyzes.

Keywords: glass-polyester composite, glass fibre, traction and flexion tests, SEM analyzes

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999 Photoluminescence of Barium and Lithium Silicate Glasses and Glass Ceramics Doped with Rare Earth Ions

Authors: Augustas Vaitkevicius, Mikhail Korjik, Eugene Tretyak, Ekaterina Trusova, Gintautas Tamulaitis

Abstract:

Silicate materials are widely used as luminescent materials in amorphous and crystalline phase. Lithium silicate glass is popular for making neutron sensitive scintillation glasses. Cerium-doped single crystalline silicates of rare earth elements and yttrium have been demonstrated to be good scintillation materials. Due to their high thermal and photo-stability, silicate glass ceramics are supposed to be suitable materials for producing light converters for high power white light emitting diodes. In this report, the influence of glass composition and crystallization on photoluminescence (PL) of different silicate glasses was studied. Barium (BaO-2SiO₂) and lithium (Li₂O-2SiO₂) glasses were under study. Cerium, dysprosium, erbium and europium ions as well as their combinations were used for doping. The influence of crystallization was studied after transforming the doped glasses into glass ceramics by heat treatment in the temperature range of 550-850 degrees Celsius for 1 hour. The study was carried out by comparing the photoluminescence (PL) spectra, spatial distributions of PL parameters and quantum efficiency in the samples under study. The PL spectra and spatial distributions of their parameters were obtained by using confocal PL microscopy. A WITec Alpha300 S confocal microscope coupled with an air cooled CCD camera was used. A CW laser diode emitting at 405 nm was exploited for excitation. The spatial resolution was in sub-micrometer domain in plane and ~1 micrometer perpendicularly to the sample surface. An integrating sphere with a xenon lamp coupled with a monochromator was used to measure the external quantum efficiency. All measurements were performed at room temperature. Chromatic properties of the light emission from the glasses and glass ceramics have been evaluated. We observed that the quantum efficiency of the glass ceramics is higher than that of the corresponding glass. The investigation of spatial distributions of PL parameters revealed that heat treatment of the glasses leads to a decrease in sample homogeneity. In the case of BaO-2SiO₂: Eu, 10 micrometer long needle-like objects are formed, when transforming the glass into glass ceramics. The comparison of PL spectra from within and outside the needle-like structure reveals that the ratio between intensities of PL bands associated with Eu²⁺ and Eu³⁺ ions is larger in the bright needle-like structures. This indicates a higher degree of crystallinity in the needle-like objects. We observed that the spectral positions of the PL bands are the same in the background and the needle-like areas, indicating that heat treatment imposes no significant change to the valence state of the europium ions. The evaluation of chromatic properties confirms applicability of the glasses under study for fabrication of white light sources with high thermal stability. The ability to combine barium and lithium glass matrixes and doping by Eu, Ce, Dy, and Tb enables optimization of chromatic properties.

Keywords: glass ceramics, luminescence, phosphor, silicate

Procedia PDF Downloads 283