Modifiable Silicones for Harsh Environments

2011 ◽  
Vol 2011 (1) ◽  
pp. 000090-000098 ◽  
Author(s):  
Michelle Velderrain ◽  
Matthew Lindberg
Keyword(s):  
Elevated Temperatures ◽  
Electronic Devices ◽  
Polymeric Materials ◽  
Harsh Environments ◽  
Electrically Conductive ◽  
Polymeric Systems ◽  
Low Modulus ◽  
Conductive Fillers ◽  
Processing Techniques

Silicones have been used for decades in aerospace and other harsh environments where temperature extremes are common. As the level of sophistication increases for electronic devices to serve these industries where failure is not an option, the material supplier has to also be able to meet these needs. Silicones are polymeric materials composed primarily of repeating silicon and oxygen bonds, known as siloxanes, which can be optimized for various chemical and physical properties by incorporating different organic groups onto the silicon atom. Employing advanced processing techniques to the siloxane system can also greatly reduce mobile siloxane molecules to reduce contamination that can cause electronic failures during assembly or operation. Siloxane based polymeric systems are also unique polymers compared to standard organic based materials in that they have a large free volume that imparts a low modulus which absorbs stresses during thermal cycling as well as not degrading at continuous operating temperatures up to 250 C. They are also slightly polar which allows the incorporation of fillers to impart a variety of unique properties. Filler technology is also a rapidly growing enterprise where fillers with various particle sizes and shapes can be added to silicones to impart key properties such as maintaining electric conductivity at elevated temperatures. This paper will explain fundamentals of silicone chemistry and processing related to getting the optimal performance in harsh environments. A case study comparing two different electrically conductive fillers and how they can influence the electrical conductivity at elevated temperatures will be presented.

Novel organic, polymeric materials for electronics applications

2002 ◽  
Vol 722 ◽  
Author(s):  
Ram W. Sabnis ◽  
Mary J. Spencer ◽  
Douglas J. Guerrero
Keyword(s):  
Optical Density ◽  
Chemical Vapor ◽  
Polymeric Materials ◽  
Substantial Improvement ◽  
Polymeric Systems ◽  
Patterned Wafers ◽  
Visible Spectra ◽  
Potential Applications ◽  
Deep Ultraviolet ◽  
Deposited Films

AbstractNovel organic, polymeric materials and processes of depositing thin films on electronics substrates by chemical vapor deposition (CVD) have been developed and the lithographic behavior of photoresist coated over these CVD films at deep ultraviolet (DUV) wavelength has been evaluated. The specific monomers synthesized for DUV applications include [2.2](1,4)- naphthalenophane, [2.2](9,10)-anthracenophane and their derivatives which showed remarkable film uniformity on flat wafers and conformality over structured topography wafers, upon polymerization by CVD. The chemical, physical and optical properties of the deposited films have been characterized by measuring parameters such as thickness uniformity, solubility, conformality, adhesion to semiconductor substrates, ultraviolet-visible spectra, optical density, optical constants, defectivity, and resist compatibility. Scanning electron microscope (SEM) photos of cross-sectioned patterned wafers showed verticle profiles with no footing, standing waves or undercut. Resist profiles down to 0.10 νm dense lines and 0.09 νm isolated lines were achieved in initial tests. CVD coatings generated 96-100% conformal films, which is a substantial improvement over commercial spin-on polymeric systems. The light absorbing layers have high optical density at 248 nm and are therefore capable materials for DUV lithography applications. CVD is a potentially useful technology to extend lithography for sub-0.15 νm devices. These films have potential applications in microelectronics, optoelectronics and photonics.

scholarly journals Simplification and Detection of Outlying Trajectories from Batch and Streaming Data Recorded in Harsh Environments

2019 ◽  
Vol 8 (6) ◽  
pp. 272 ◽  
Author(s):  
Iq Reviessay Pulshashi ◽  
Hyerim Bae ◽  
Hyunsuk Choi ◽  
Seunghwan Mun ◽  
Riska Asriana Sutrisnowati
Keyword(s):  
South Korea ◽  
Real World ◽  
Experimental Evaluation ◽  
Streaming Data ◽  
Harsh Environments ◽  
Noise Filtering ◽  
New Approach ◽  
Detection Algorithms ◽  
Outlying Point

Analysis of trajectory such as detection of an outlying trajectory can produce inaccurate results due to the existence of noise, an outlying point-locations that can change statistical properties of the trajectory. Some trajectories with noise are repairable by noise filtering or by trajectory-simplification. We herein propose the application of a trajectory-simplification approach in both batch and streaming environments, followed by benchmarking of various outlier-detection algorithms for detection of outlying trajectories from among simplified trajectories. Experimental evaluation in a case study using real-world trajectories from a shipyard in South Korea shows the benefit of the new approach.

scholarly journals Protein Nanowires: the Electrification of the Microbial World and Maybe Our Own

2020 ◽  
Vol 202 (20) ◽  
Author(s):  
Derek R. Lovley ◽  
Dawn E. Holmes
Keyword(s):  
Electron Transport ◽  
Long Range ◽  
Electronic Devices ◽  
Electricity Production ◽  
Microbial World ◽  
Electrically Conductive ◽  
Anaerobic Digesters ◽  
Content Type ◽  
Type Iv ◽  
Type Iv Pilin

ABSTRACT Electrically conductive protein nanowires appear to be widespread in the microbial world and are a revolutionary “green” material for the fabrication of electronic devices. Electrically conductive pili (e-pili) assembled from type IV pilin monomers have independently evolved multiple times in microbial history as have electrically conductive archaella (e-archaella) assembled from homologous archaellin monomers. A role for e-pili in long-range (micrometer) extracellular electron transport has been demonstrated in some microbes. The surprising finding of e-pili in syntrophic bacteria and the role of e-pili as conduits for direct interspecies electron transfer have necessitated a reassessment of routes for electron flux in important methanogenic environments, such as anaerobic digesters and terrestrial wetlands. Pilin monomers similar to those found in e-pili may also be a major building block of the conductive “cables” that transport electrons over centimeter distances through continuous filaments of cable bacteria consisting of a thousand cells or more. Protein nanowires harvested from microbes have many functional and sustainability advantages over traditional nanowire materials and have already yielded novel electronic devices for sustainable electricity production, neuromorphic memory, and sensing. e-pili can be mass produced with an Escherichia coli chassis, providing a ready source of material for electronics as well as for studies on the basic mechanisms for long-range electron transport along protein nanowires. Continued exploration is required to better understand the electrification of microbial communities with microbial nanowires and to expand the “green toolbox” of sustainable materials for wiring and powering the emerging “Internet of things.”

Rubber-like electrically conductive polymeric materials with shape memory

2013 ◽  
Vol 22 (5) ◽  
pp. 055024 ◽  
Author(s):  
H P Cui ◽  
C L Song ◽  
W M Huang ◽  
C C Wang ◽  
Y Zhao
Keyword(s):  
Shape Memory ◽  
Polymeric Materials ◽  
Electrically Conductive

Electronic, Ionic, and Mixed Conduction in Polymeric Systems

2021 ◽  
Vol 51 (1) ◽  
Author(s):  
Elayne M. Thomas ◽  
Phong H. Nguyen ◽  
Seamus D. Jones ◽  
Michael L. Chabinyc ◽  
Rachel A. Segalman
Keyword(s):  
Materials Science ◽  
Transport Coefficients ◽  
Polymeric Materials ◽  
Annual Review ◽  
Publication Date ◽  
Energy Storage Devices ◽  
Polymeric Systems ◽  
Storage Devices ◽  
Technological Advances ◽  
Performance Benchmark

Polymers that simultaneously transport electrons and ions are paramount to drive the technological advances necessary for next-generation electrochemical devices, including energy storage devices and bioelectronics. However, efforts to describe the motion of ions or electrons separately within polymeric systems become inaccurate when both species are present. Herein, we highlight the basic transport equations necessary to rationalize mixed transport and the multiscale materials properties that influence their transport coefficients. Potential figures of merit that enable a suitable performance benchmark in mixed conducting systems independent of end application are discussed. Practical design and implementation of mixed conducting polymers require an understanding of the evolving nature of structure and transport with ionic and electronic carrier density to capture the dynamic disorder inherent in polymeric materials. Expected final online publication date for the Annual Review of Materials Science, Volume 51 is July 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

scholarly journals The Effects of Preschoolers’ Media Usage Habits on Their Daily Life and Sustainability

2019 ◽  
Vol 10 (2) ◽  
pp. 112-128
Author(s):  
Begum Canaslan Akyar ◽  
Özkan Sapsaglam
Keyword(s):  
Home Environment ◽  
Negative Impact ◽  
Electronic Devices ◽  
Media Usage ◽  
Case Study Design ◽  
Digital World ◽  
Digital Contents ◽  
Reported Study ◽  
Different Levels

Abstract Today’s children are born into a digital world and are exposed to various electronic devices and digital contents both in the home environment and other environments since the first years of life. Children, who are a natural recipient of the environment in which they live, are exposed to the effects of the digital world at different levels and reflect these effects in different ways. The purpose of the reported study is to investigate if preschoolers’ daily media usage habits affects their drawings. This study is planned according to the case study design of qualitative research methods. The study was conducted with 15 preschoolers and their parents. There were nine boys and six girls in the study. The preschoolers’ drawings and their parents’ interview data were analyzed by using the descriptive analyzing method. The study result shows that there are differences between boys and girls media usage habits. Boys spend more time with media tools than girls. Additionally, boys are exposed to more inappropriate content because of their preferences. The analysis of their drawings revealed that boys are more affected than girls from media contents since boys’ drawings include more characters from media than girls. It can thus be suggested that media tools might be harmful when they are used in a developmentally inappropriate way, and excessive media tool usage has negative impact on children. Therefore, the reported study recommends that parents and caregivers take some precautions to limit preschoolers from spending time with media tools and to control content of children’s activity.

scholarly journals Biomedical applications of electrically conductive polymeric systems

e-Polymers ◽  
2012 ◽  
Vol 12 (1) ◽  
Author(s):  
Joseph Jagur-Grodzinski
Keyword(s):  
Biomedical Applications ◽  
Bone Cells ◽  
Clinical Analysis ◽  
Precise Determination ◽  
Electrically Conductive ◽  
Polymeric Systems ◽  
Neural Tissues ◽  
Novel Applications ◽  
Chemical Materials

AbstractProperties of the electrically conductive polymers (ECPs) enable introduction of several novel applications in various fields, among others, as biomedical materials. Their use as scaffolds for tissue engineering and recovery of damaged neural tissues is especially advantageous. They may also be used for the electrically induced drug release and delivery, and as very sensitive biosensors for clinical applications. Another use is the detection and precision of the biologically important chemical materials. They have been shown to modulate and accelerate activities of the nerve, skeletal, muscle, and bone cells. Cell growth, migration and adhesion, may be stimulated by applying electric potential. Synthesis of DNA, secretion of proteins, and transformations of stem cells may be enhanced. Clinical analysis using ECP-based biosensors make possible the precise determination of the exact composition of individual DNA molecules, and thus enable early detection and treatment of genetically related diseases. Electrochemical (EC) approach of ECP-sensors enables precise determination of concentrations of several biologically important chemicals.

scholarly journals Cryostructuring of Polymeric Systems. 50.† Cryogels and Cryotropic Gel-Formation: Terms and Definitions

Gels ◽  
2018 ◽  
Vol 4 (3) ◽  
pp. 77 ◽  
Author(s):  
Vladimir Lozinsky
Keyword(s):  
Polymeric Materials ◽  
Gel Formation ◽  
Polymeric Systems ◽  
The Past ◽  
Marked Variability ◽  
Conference Presentations

A variety of cryogenically-structured polymeric materials are of significant scientific and applied interest in various areas. However, in spite of considerable attention to these materials and intensive elaboration of their new examples, as well as the impressive growth in the number of the publications and patents on this topic over the past two decades, a marked variability of the used terminology and definitions is frequently met with in the papers, reviews, theses, patents, conference presentations, advertising materials and so forth. Therefore, the aim of this brief communication is to specify the basic terms and definitions in the particular field of macromolecular science.

Parallel Data Reduction Techniques for Big Datasets

2013 ◽  
pp. 72-93 ◽  
Author(s):  
Ahmet Artu Yıldırım ◽  
Cem Özdoğan ◽  
Dan Watson
Keyword(s):  
Big Data ◽  
Data Reduction ◽  
Memory Systems ◽  
Discrete Wavelet ◽  
Server Side ◽  
Advantages And Disadvantages ◽  
Reduction Techniques ◽  
Parallel Data ◽  
Processing Techniques

Data reduction is perhaps the most critical component in retrieving information from big data (i.e., petascale-sized data) in many data-mining processes. The central issue of these data reduction techniques is to save time and bandwidth in enabling the user to deal with larger datasets even in minimal resource environments, such as in desktop or small cluster systems. In this chapter, the authors examine the motivations behind why these reduction techniques are important in the analysis of big datasets. Then they present several basic reduction techniques in detail, stressing the advantages and disadvantages of each. The authors also consider signal processing techniques for mining big data by the use of discrete wavelet transformation and server-side data reduction techniques. Lastly, they include a general discussion on parallel algorithms for data reduction, with special emphasis given to parallel wavelet-based multi-resolution data reduction techniques on distributed memory systems using MPI and shared memory architectures on GPUs along with a demonstration of the improvement of performance and scalability for one case study.

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