Lightweight Nanocomposites Polymers for Shielding Application

2021 ◽  
pp. 554-575
Author(s):  
Mohamed Darwish
Keyword(s):  
Electromagnetic Waves ◽  
Low Cost ◽  
Radiation Shielding ◽  
Multiple Reflections ◽  
Absorption Frequency ◽  
Aerospace Applications ◽  
Absorber Material ◽  
Wide Range ◽  
Potential Applications ◽  
Conductive Fillers

Electromagnetic waves can have serious effects on human health by long-term exposure. Developing lightweight materials with good electromagnetic radiation shielding (EMS) that could prevent interference is a high desire for protection. Nanocomposites polymers have a wide range of potential applications and offers suggested solutions in environmental and aerospace applications. This chapter will cover the current challenge in the reduction of electromagnetic wave by developing lightweight absorber material with a wide absorption frequency. A wide range of different nanocomposites polymers contain conductive fillers such as metal or magnetic nanoparticles and carbon-based materials will be discussed. In addition, EMS mechanisms of reflection, absorption, and multiple reflections will be discussed. The unique of the chemical and physical properties of nanocomposites polymers are promising for shielding with low-cost environmentally friendly material.

Lightweight Nanocomposites Polymers for Shielding Application

2019 ◽  
pp. 206-233
Author(s):  
Mohamed Darwish
Keyword(s):  
Electromagnetic Waves ◽  
Low Cost ◽  
Radiation Shielding ◽  
Multiple Reflections ◽  
Absorption Frequency ◽  
Aerospace Applications ◽  
Absorber Material ◽  
Wide Range ◽  
Potential Applications ◽  
Conductive Fillers

Electromagnetic waves can have serious effects on human health by long-term exposure. Developing lightweight materials with good electromagnetic radiation shielding (EMS) that could prevent interference is a high desire for protection. Nanocomposites polymers have a wide range of potential applications and offers suggested solutions in environmental and aerospace applications. This chapter will cover the current challenge in the reduction of electromagnetic wave by developing lightweight absorber material with a wide absorption frequency. A wide range of different nanocomposites polymers contain conductive fillers such as metal or magnetic nanoparticles and carbon-based materials will be discussed. In addition, EMS mechanisms of reflection, absorption, and multiple reflections will be discussed. The unique of the chemical and physical properties of nanocomposites polymers are promising for shielding with low-cost environmentally friendly material.

Frequency Selective Surface for Infrared Transmission Suppression at Atmospheric Window

2018 ◽  
Vol 937 ◽  
pp. 89-95
Author(s):  
Xiao Li Chen ◽  
Chang Hui Tian ◽  
Zhi Xin Che
Keyword(s):  
Electromagnetic Waves ◽  
Far Infrared ◽  
Black Body ◽  
Frequency Selective Surface ◽  
Infrared Transmission ◽  
Infrared Band ◽  
Infrared Transmittance ◽  
Wide Range ◽  
Potential Applications ◽  
Frequency Selective

A double screen infrared frequency selective surface (FSS) with dual transmission stopbands was proposed and numerically investigated. Simulation results show that the infrared transmittance of the structure is lower than 10% in mid-infrared band (3~5 μm) and far-infrared band (8 ~14 μm).This structure is polarization insensitive to the incident electromagnetic waves. For a wide range of incident angles from 0° to 60°, the infrared transmittance of the structure is still lower than 25% in the band of interest. Compared with black body, the radiation ratio of structure is lower in the MWIR and LWIR ranges. The structure provide the potential applications for infrared stealth.

Insights into bio-synthesis of nanoparticles by Shewanella genus

2021 ◽  
Author(s):  
Vishnu D. Rajput ◽  
Tatiana Minkina ◽  
Richard Kimber ◽  
Vipin Kumar Singh ◽  
Sudhir Shende ◽  
...  
Keyword(s):  
Focal Point ◽  
Low Cost ◽  
Model Organism ◽  
Metal Species ◽  
Synthesis Methods ◽  
Influence Of Process Parameters ◽  
Synthesis Of Nanoparticles ◽  
Current State ◽  
Wide Range ◽  
Potential Applications

The exploitation of microorganisms for the fabrication of nanoparticles (NPs) has garnered considerable research interest globally. The microbiological transformation of metals and metal salts into respective NPs can be achieved under environmentally benign conditions, offering a more sustainable alternative to chemical synthesis methods. Species of the metal-reducing bacterial genus Shewanella are able to couple the oxidation of various electron donors including lactate, pyruvate and hydrogen, to the reduction of a wide range of metal species, resulting in biomineralization of a multitude of metal NPs. Single metal-based NPs as well as composite materials with properties equivalent or even superior to physically and chemically produced NPs have been synthesized by a number of Shewanella species. A mechanistic understanding of electron transfer mediated bioreduction of metals into respective NPs by Shewanella is crucial in maximizing NP yields and directing the synthesis to produce fine-tuned NPs with tailored properties. In addition, thorough investigations into the influence of process parameters controlling the biosynthesis is another focal point for optimizing the process of NP generation. Synthesis of metal-based NPs using Shewanella species offers a low-cost, eco-friendly alternative to current physiochemical methods. This article aims to shed light on the contribution of Shewanella as a model organism in the biosynthesis of a variety of NPs, and critically reviews the current state of knowledge on factors controlling their synthesis, characterization, potential applications in different sectors and future prospects.

scholarly journals A Low-Cost Terahertz Camera

2019 ◽  
Vol 9 (12) ◽  
pp. 2531 ◽  
Author(s):  
François Blanchard ◽  
Joel Edouard Nkeck ◽  
Dominique Matte ◽  
Riad Nechache ◽  
David G. Cooke
Keyword(s):  
Electromagnetic Waves ◽  
Low Cost ◽  
Rapid Development ◽  
Cost Effective ◽  
Night Vision ◽  
Thz Imaging ◽  
Dynamic Background ◽  
Imaging Device ◽  
Simple Modification ◽  
Wide Range

Cost effective imaging is required for a wide range of scientific and engineering applications. For electromagnetic waves in the terahertz (THz) frequency range, a key missing element that has prevented widespread applications in this spectral range is an inexpensive and efficient imaging device. In recent years, vanadium oxide based thermal sensors have rapidly entered the market for night vision capability. At the same time, sensors based on this technology have been applied to the THz domain, but with two orders of magnitude larger pricing range. Here we show that, with a simple modification, a commercially available thermal imaging camera can function as a THz imaging device. By comparing a commercially available THz camera and this low-cost device, we identify the main sensitivity difference is not attributed to anything intrinsic to the devices, but rather to the analog-to-digital converter and dynamic background subtraction capability. This demonstration of a low-cost THz camera may aid in the rapid development of affordable THz imaging solutions for industrial and scientific applications.

scholarly journals Recent Advances on Conducting Polymers Based Nanogenerators for Energy Harvesting

Micromachines ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1308
Author(s):  
Weichi Zhang ◽  
Liwen You ◽  
Xiao Meng ◽  
Bozhi Wang ◽  
Dabin Lin
Keyword(s):  
Energy Harvesting ◽  
Conducting Polymers ◽  
High Performance ◽  
Large Scale ◽  
Low Cost ◽  
Scale Production ◽  
Environmentally Sustainable ◽  
Recent Advances ◽  
Wide Range ◽  
Potential Applications

With the rapid growth of numerous portable electronics, it is critical to develop high-performance, lightweight, and environmentally sustainable energy generation and power supply systems. The flexible nanogenerators, including piezoelectric nanogenerators (PENG) and triboelectric nanogenerators (TENG), are currently viable candidates for combination with personal devices and wireless sensors to achieve sustained energy for long-term working circumstances due to their great mechanical qualities, superior environmental adaptability, and outstanding energy-harvesting performance. Conductive materials for electrode as the critical component in nanogenerators, have been intensively investigated to optimize their performance and avoid high-cost and time-consuming manufacture processing. Recently, because of their low cost, large-scale production, simple synthesis procedures, and controlled electrical conductivity, conducting polymers (CPs) have been utilized in a wide range of scientific domains. CPs have also become increasingly significant in nanogenerators. In this review, we summarize the recent advances on CP-based PENG and TENG for biomechanical energy harvesting. A thorough overview of recent advancements and development of CP-based nanogenerators with various configurations are presented and prospects of scientific and technological challenges from performance to potential applications are discussed.

Mechanical Properties of Epoxy Nanocomposites Using Alumina as Reinforcement - A Review

2015 ◽  
Vol 30 ◽  
pp. 9-38 ◽  
Author(s):  
Deesy Pinto ◽  
Luís Bernardo ◽  
Ana Amaro ◽  
Sérgio Lopes
Keyword(s):  
Low Cost ◽  
Chemical Properties ◽  
Alumina Nanoparticles ◽  
Future Directions ◽  
Aerospace Applications ◽  
Viable Solution ◽  
Wide Range ◽  
Alumina Particles ◽  
Ep Matrix ◽  
And Chemical Properties

Polymers and their composites find use in many engineering applications as alternative products to metal-based ones and, nowadays, have wide technical applications. One of the most used composite materials is the epoxy resins (EP), which is a thermoset polymer matrix. After cure, this material displays some excellent mechanical, thermal, electrical and chemical properties. For these reasons, it has been widely used for a wide range of automotive and aerospace applications, as well as for shipbuilding or electronic devices. However, EP has poor resistance to crack propagation and is brittle. So, in recent years, a considerable amount of research has been carried out to improve the performance of the toughness of EP. The most common studied technique consist to reinforce the EP matrix with rigid nanoparticle fillers, such as alumina, silica, mica, talc, organoclays, nanoclays, carbon nanotubes, TiO2, among others. Among these nanofillers type, nanosize alumina particles has not been widely studied. However, recent studies have reported that the use of functionalized nanosize alumina particles as nanofiller can significantly improve the properties of the nanocomposite, even with low contents. These results, combined with the low cost of the alumina, show that the reinforcement of EP with alumina nanoparticles is a viable solution. In this paper, an attempt is made to review and highlight some recent findings and also some trends to show future directions and opportunities for the development of polymer nanocomposites reinforced with alumina nanoparticles.

scholarly journals A Low Cost Inkjet-Printed Mass Sensor Using a Frequency Readout Strategy

Sensors ◽  
2021 ◽  
Vol 21 (14) ◽  
pp. 4878
Author(s):  
Bruno Andò ◽  
Salvatore Baglio ◽  
Vincenzo Marletta ◽  
Ruben Crispino
Keyword(s):  
Cantilever Beam ◽  
Low Cost ◽  
Strain Sensor ◽  
Mass Sensor ◽  
Mass Sensors ◽  
Target Mass ◽  
Wide Range ◽  
Planar Coil ◽  
Potential Applications ◽  
Actuation Mode

The development of low-cost mass sensors is of unique interest for the scientific community due to the wide range of fields requiring these kind of devices. In this paper, a full inkjet-printed mass sensor is proposed. The device is based on a PolyEthylene Terephthalate (PET) cantilever beam (operating in its first natural frequency) where a strain-sensor and a planar coil have been realized by a low-cost InkJet Printing technology to implement the sensing and actuation strategies, respectively. The frequency readout strategy of the sensor presents several advantages, such as the intrinsic robustness against instabilities of the strain sensor, the residual stress of the cantilever beam, the target mass material, and the distance between the permanent magnet and the actuation coil (which changes as a function of the target mass values). However, the frictionless actuation mode represents another shortcoming of the sensor. The paper describes the sensor design, realization, and characterization while investigating its expected behavior by exploiting dedicate models. The working span of the device is 0–0.36 g while its resolution is in the order of 0.001 g, thus addressing a wide range of potential applications requiring very accurate mass measurements within a narrow operating range.

TEM study of boron additions to cobalt aluminide

1988 ◽  
Vol 46 ◽  
pp. 546-547
Author(s):  
Gerald B. Feldewerth
Keyword(s):  
High Temperature ◽  
Turbine Engines ◽  
Major Drawback ◽  
University Of Missouri ◽  
Specific Strength ◽  
Aerospace Applications ◽  
Wide Range ◽  
Ordered Alloys ◽  
The University ◽  
Very High

In recent years an increasing emphasis has been placed on the study of high temperature intermetallic compounds for possible aerospace applications. One group of interest is the B2 aiuminides. This group of intermetaliics has a very high melting temperature, good high temperature, and excellent specific strength. These qualities make it a candidate for applications such as turbine engines. The B2 aiuminides exist over a wide range of compositions and also have a large solubility for third element substitutional additions, which may allow alloying additions to overcome their major drawback, their brittle nature.One B2 aluminide currently being studied is cobalt aluminide. Optical microscopy of CoAl alloys produced at the University of Missouri-Rolla showed a dramatic decrease in the grain size which affects the yield strength and flow stress of long range ordered alloys, and a change in the grain shape with the addition of 0.5 % boron.

Microwaves: Application in Electron Microscopy

1990 ◽  
Vol 48 (3) ◽  
pp. 140-141
Author(s):  
Anthony S-Y Leong ◽  
David W Gove
Keyword(s):  
Electron Microscopy ◽  
Light Microscopy ◽  
Chemical Reactions ◽  
Electromagnetic Waves ◽  
Tissue Fixation ◽  
Primary Method ◽  
Dipolar Molecules ◽  
Wide Range ◽  
Time Required ◽  
Cryostat Sections

Microwaves (MW) are electromagnetic waves which are commonly generated at a frequency of 2.45 GHz. When dipolar molecules such as water, the polar side chains of proteins and other molecules with an uneven distribution of electrical charge are exposed to such non-ionizing radiation, they oscillate through 180° at a rate of 2,450 million cycles/s. This rapid kinetic movement results in accelerated chemical reactions and produces instantaneous heat. MWs have recently been applied to a wide range of procedures for light microscopy. MWs generated by domestic ovens have been used as a primary method of tissue fixation, it has been applied to the various stages of tissue processing as well as to a wide variety of staining procedures. This use of MWs has not only resulted in drastic reductions in the time required for tissue fixation, processing and staining, but have also produced better cytologic images in cryostat sections, and more importantly, have resulted in better preservation of cellular antigens.

Development of a Capacitor Probe to Detect Subsurface Deterioration in Concrete

1997 ◽  
Vol 503 ◽  
Author(s):  
B. K. Diefenderfer ◽  
I. L. Al-Qadi ◽  
J. J. Yoho ◽  
S. M. Riad ◽  
A. Loulizi
Keyword(s):  
Dielectric Constant ◽  
Portland Cement ◽  
Electromagnetic Waves ◽  
Low Cost ◽  
Complex Dielectric Constant ◽  
Life Cycle Costs ◽  
Parallel Plates ◽  
Portland Cement Concrete ◽  
Cement Concrete ◽  
Set Up

ABSTRACTPortland cement concrete (PCC) structures deteriorate with age and need to be maintained or replaced. Early detection of deterioration in PCC (e.g., alkali-silica reaction, freeze/thaw damage, or chloride presence) can lead to significant reductions in maintenance costs. However, it is often too late to perform low-cost preventative maintenance by the time deterioration becomes evident. By developing techniques that would enable civil engineers to evaluate PCC structures and detect deterioration at early stages (without causing further damage), optimization of life-cycle costs of the constructed facility and minimization of disturbance to the facility users can be achieved.Nondestructive evaluation (NDE) methods are potentially one of the most useful techniques ever developed for assessing constructed facilities. They are noninvasive and can be performed rapidly. Portland cement concrete can be nondestructively evaluated by electrically characterizing its complex dielectric constant. The real part of the dielectric constant depicts the velocity of electromagnetic waves in PCC. The imaginary part, termed the “loss factor,” describes the conductivity of PCC and the attenuation of electromagnetic waves.Dielectric properties of PCC have been investigated in a laboratory setting using a parallel plate capacitor operating in the frequency range of 0.1 to 40.1MIHz. This capacitor set-up consists of two horizontal-parallel plates with an adjustable separation for insertion of a dielectric specimen (PCC). While useful in research, this approach is not practical for field implementation. A new capacitor probe has been developed which consists of two plates, located within the same horizontal plane, for placement upon the specimen to be tested. Preliminary results show that this technique is feasible and results are promising; further testing and evaluation is currently underway.

Sign in / Sign up

Export Citation Format

Share Document