scholarly journals A Study on the Techniques of Composite Mold Structure for Hovercraft Using New Material System

2008 ◽  
Vol 32 (9) ◽  
pp. 699-703
Author(s):  
Yun-Hae Kim ◽  
Chang-Won Bae ◽  
Keun-Sil Park ◽  
Sung-Youl Bae ◽  
Kyung-Man Moon ◽  
...  
Keyword(s):  
Material System ◽  
New Material

Cross-sectional TEM specimen preparation from magneto-optical disk by ultramicrotomy

1993 ◽  
Vol 51 ◽  
pp. 236-237
Author(s):  
F. Shaapur ◽  
M.J. Kim ◽  
Seh Kwang Lee ◽  
Soon Gwang Kim
Keyword(s):  
System Development ◽  
Thin Foil ◽  
Specimen Preparation ◽  
Material System ◽  
Cross Sectional ◽  
Protective Layers ◽  
New Material ◽  
Diamond Saw ◽  
Original Production ◽  
Thick Medium

TEM characterization and microanalysis of the recording media is crucial and complementary to new material system development as well as quality control applications. Due to the type of material generally used for supporting the medium, i.e., a polymer, conventional macro- and microthinning procedures for thin foil preparation are not applicable. Ultramicrotorny (UM) is a viable option and has been employed in previous similar studies. In this work UM has been used for preparation of XTEM samples from a magneto-optical (MO) recording medium in its original production format.The as-received material system consisted of a 4-layer, 2100 Å thick medium including a 300 Å TbFeCo layer enveloped by silicon nitride protective layers supported on a 1.2 mm thick × 135 mm (5.25 in.) diameter polycarbonate disk. Recording tracks had an approximate pitch of 1.6 μm separated by 800 Å deep peripheral grooves. Using a Buehler Isomet low-speed diamond saw, 1 mm wide and 20 mm long strips were cut out of the disk along the recording tracks.

Attribute Based Selection of Thermoplastic Resin for Vacuum Infusion Process

2011 ◽  
Vol 1 (3) ◽  
pp. 31-52 ◽  
Author(s):  
R. T. Durai Prabhakaran ◽  
Aage Lystrup ◽  
Tom Løgstrup Andersen
Keyword(s):  
Material System ◽  
Mathematical Tool ◽  
Thermoplastic Resin ◽  
Thermoplastic Polymers ◽  
Vacuum Infusion ◽  
Thermosetting Polymers ◽  
Current Scenario ◽  
New Material ◽  
Selection Of ◽  
Vacuum Infusion Process

The composite industry looks toward a new material system (resins) based on thermoplastic polymers for the vacuum infusion process, similar to the infusion process using thermosetting polymers. A large number of thermoplastics are available in the market with a variety of properties suitable for different engineering applications, and few of those are available in a not yet polymerised form suitable for resin infusion. The proper selection of a new resin system among these thermoplastic polymers is a concern for manufactures in the current scenario and a special mathematical tool would be beneficial. In this paper, the authors introduce a new decision making tool for resin selection based on significant attributes. This article provides a broad overview of suitable thermoplastic material systems for vacuum infusion process available in today’s market. An illustrative example—resin selection for vacuum infused of a wind turbine blade—is shown to demonstrate the intricacies involved in the proposed methodology for resin selection.

Attribute Based Selection of Thermoplastic Resin for Vacuum Infusion Process

2012 ◽  
pp. 267-288
Author(s):  
R. T. Durai Prabhakaran ◽  
Aage Lystrup ◽  
Tom Løgstrup Andersen
Keyword(s):  
Material System ◽  
Mathematical Tool ◽  
Thermoplastic Resin ◽  
Thermoplastic Polymers ◽  
Vacuum Infusion ◽  
Thermosetting Polymers ◽  
Current Scenario ◽  
New Material ◽  
Selection Of ◽  
Vacuum Infusion Process

The composite industry looks toward a new material system (resins) based on thermoplastic polymers for the vacuum infusion process, similar to the infusion process using thermosetting polymers. A large number of thermoplastics are available in the market with a variety of properties suitable for different engineering applications, and few of those are available in a not yet polymerised form suitable for resin infusion. The proper selection of a new resin system among these thermoplastic polymers is a concern for manufactures in the current scenario and a special mathematical tool would be beneficial. In this paper, the authors introduce a new decision making tool for resin selection based on significant attributes. This article provides a broad overview of suitable thermoplastic material systems for vacuum infusion process available in today’s market. An illustrative example—resin selection for vacuum infused of a wind turbine blade—is shown to demonstrate the intricacies involved in the proposed methodology for resin selection.

Integrated Photonic Circuits in Gallium Nitride and Aluminum Nitride

2014 ◽  
Vol 23 (01n02) ◽  
pp. 1450001 ◽  
Author(s):  
Chi Xiong ◽  
Wolfram Pernice ◽  
Carsten Schuck ◽  
Hong X. Tang
Keyword(s):  
High Speed ◽  
Optical Signal ◽  
Silicon Substrates ◽  
Material System ◽  
Group Iii ◽  
Electro Optic ◽  
New Material ◽  
Nanophotonic Circuits ◽  
Group Iii Nitride ◽  
On Chip

Integrated optics is a promising optical platform both for its enabling role in optical interconnects and applications in on-chip optical signal processing. In this paper, we discuss the use of group III-nitride (GaN, AlN) as a new material system for integrated photonics compatible with silicon substrates. Exploiting their inherent second-order nonlinearity we demonstrate and second, third harmonic generation in GaN nanophotonic circuits and high-speed electro-optic modulation in AlN nanophotonic circuits.

scholarly journals Experimental and Numerical Studies on Ballistic Laminates on the Polyethylene and Polypropylene Matrix

2017 ◽  
Vol 35 (02) ◽  
pp. 187-197 ◽  
Author(s):  
P. Mayer ◽  
D. Pyka ◽  
K. Jamroziak ◽  
J. Pach ◽  
M. Bocian
Keyword(s):  
Hybrid Composite ◽  
Material System ◽  
Aramid Fibers ◽  
Advantages And Disadvantages ◽  
Numerical Studies ◽  
Thermoplastic Matrix ◽  
Material Systems ◽  
New Material ◽  
Innovative Material ◽  
Polypropylene Matrix

ABSTRACTThe paper analyzes the issues relating to the applicability of innovative material systems for flexible composite armors. The authors made several samplings of aramid fibers (Kevlar 49) by replacing the epoxy resin base, which is often described in the literature, with the thermoplastic matrix - polyethylene (HDPE) and polypropylene (PP). The samples were fired with .38 Special Full Metal Jacketed (FMJ) ammunition produced by the S&B Company, and then the process of firing was modeled in the ABAQUS program. The advantages and disadvantages of the new material system including the possibility of its use in the construction of hybrid composite armors have been presented on the basis of the results of numerical analyses and ballistic tests.

Growth and Characterization of Inas Quantum Dots on Silicon

1999 ◽  
Vol 583 ◽  
Author(s):  
L. Hansen ◽  
A. Ankudinov ◽  
F. Bensing ◽  
J. Wagner ◽  
G. Ade ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Molecular Beam Epitaxy ◽  
Molecular Beam ◽  
The Other ◽  
Material System ◽  
Inas Quantum Dots ◽  
New Material ◽  
The One ◽  
Insight Into

AbstractUp to 1011 cm−2 InAs quantum dots (QD) can be grown on Silicon(001) by molecular beam epitaxy. This very new material system is on the one hand interesting with regard to the integration of optoelectronics with silicon technology on the other hand it offers new insight into the formation of QDs. We report on RHEED, TEM and Raman studies about (in-) coherence of the QDs and on an according to our knowledge so far unknown dewetting transition in this material system. The results are being discussed on the basis of a thermodynamic model, assuming a liquid-like behavior of a strained adlayer.

scholarly journals Efficient Distortion Prediction of Additively Manufactured Parts Using Bayesian Model Transfer Between Material Systems

2020 ◽  
Vol 142 (5) ◽  
Author(s):  
Jack Francis ◽  
Arman Sabbaghi ◽  
M. Ravi Shankar ◽  
Morteza Ghasri-Khouzani ◽  
Linkan Bian
Keyword(s):  
Bayesian Model ◽  
Computation Time ◽  
Critical Issue ◽  
Material System ◽  
Element Analysis ◽  
Distortion Model ◽  
Material Systems ◽  
New Material ◽  
Model Transfer

Abstract Distortion in laser-based additive manufacturing (LBAM) is a critical issue that adversely affects the geometric integrity of additively manufactured parts and generally exhibits a complicated dependence on the underlying material. The differences in properties between distinct materials prevent the immediate application of a distortion model learned for one material to another, which introduces the challenge in LBAM of learning a distortion model for a new material system given past experiments. Current methods for investigating the distortion of different material systems typically involve finite element analysis or a large number of experiments in an empirical study. However, these methods do not learn from previous experiments and can incur significant costs in terms of computation, time, or resources. We propose a Bayesian model transfer methodology that is both physics-based and data-driven to leverage past experiments on previously studied material systems for more efficient distortion modeling of new systems. This method transfers distortion models across distinct materials based on the statistical effect equivalence framework by formulating the differences between two materials as a lurking variable. Our method reduces the experimentation and effort needed for specifying distortion models for new material systems. We validate our methodology in a case study of distortion model transfer from Ti–6Al–4V disks to 316L stainless steel disks. This case study is the first instance of model transfer between material systems and illustrates the ability of the Bayesian model transfer methodology to address the issue of comprehensive distortion modeling across varying material systems in LBAM.

scholarly journals Order parameters, broken symmetry, and topology

2021 ◽  
pp. 253-286
Author(s):  
James P. Sethna
Keyword(s):  
Liquid Crystals ◽  
Landau Theory ◽  
Local Equilibrium ◽  
Topological Defects ◽  
Order Parameters ◽  
Material System ◽  
Broken Symmetries ◽  
Gauge Symmetries ◽  
Quantum Particles ◽  
New Material

This chapter introduces order parameters -- the reduction of a complex system of interacting particles into a few fields that describe the local equilibrium behavior at each point in the system. It introduces an organized approach to studying a new material system -- identify the broken symmetries, define the order parameter, examine the elementary excitations, and classify the topological defects. It uses order parameters to describe crystals and liquid crystals, superfluids and magnets. It touches upon broken gauge symmetries and the Anderson/Higgs mechanism and an analogue to braiding of non-abelian quantum particles. Exercises explore sound, second sound, and Goldstone’s theorem; fingerprints and soccer balls; Landau theory and other methods for generating emergent theories from symmetries and commutation relations; topological defects in magnets, liquid crystals, and superfluids, and defect entanglement.

scholarly journals Electro-Optical Properties of a Polymer Dispersed and Stabilized Cholesteric Liquid Crystals System Constructed by a Stepwise UV-Initiated Radical/Cationic Polymerization

Crystals ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 282 ◽  
Author(s):  
Chen-Yue Li ◽  
Xiao Wang ◽  
Xiao Liang ◽  
Jian Sun ◽  
Chun-Xin Li ◽  
...  
Keyword(s):  
Liquid Crystal ◽  
Cationic Polymerization ◽  
Uv Light ◽  
Polymer Network ◽  
Reaction Rates ◽  
Driving Voltage ◽  
Material System ◽  
Short Period ◽  
Polymer Dispersed ◽  
New Material

Polymer-dispersed liquid crystal (PDLC) and polymer-stabilized liquid crystal (PSLC) are two typical liquid crystal (LC)/polymer composites. PDLCs are usually prepared by dispersing LC droplets in a polymer matrix, while PSLC is a system in which the alignment of LC molecules is stabilized by interactions between the polymer network and the LC molecules. In this study, a new material system is promoted to construct a coexistence system of PDLC and PSLC, namely PD&SChLC. In this new material system, a liquid-crystalline vinyl-ether monomer (LVM) was introduced to a mixture containing cholesteric liquid crystal (ChLC) and isotropic acrylate monomer (IAM). Based on the different reaction rates between LVM and IAM, the PD&SChLC architecture was built using a stepwise UV-initiated polymerization. During the preparation of the PDS&ChLC films, first, the mixture was irradiated with UV light for a short period of time to induce the free radical polymerization of IAMs, forming a phase-separated microstructure, PDLC. Subsequently, an electric filed was applied to the sample for long enough to induce the cationic polymerization of LVMs, forming the homeotropically-aligned polymer fibers within the ChLC domains, which are similar to those in a PSLC. Based on this stepwise UV-initiated radical/cationic polymerization, a PD&SChLC film with the advantages of a relatively low driving voltage, a fast response time, and a large-area processability is successful prepared. The film can be widely used in flexible displays, smart windows, and other optical devices.

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