Parametric Control of Melting Gel Morphology and Chemistry via Electrospray Deposition

2021 ◽  
Author(s):  
Michael Grzenda ◽  
Arielle Gamboa ◽  
James Mercado ◽  
Lin Lei ◽  
Jennifer Guzman ◽  
...  
Keyword(s):  
Protective Coatings ◽  
Processing Technique ◽  
Inorganic Materials ◽  
Electrospray Deposition ◽  
Irreversible Reaction ◽  
Optical Images ◽  
Melting Gels ◽  
Highly Hydrophobic ◽  
Robust Processing ◽  
Processing Techniques

Abstract Melting gels are a class of hybrid organic-inorganic, silica-based sol-gels which are solid below their glass transition temperatures, near room temperature, but show thermoplastic behavior when heated. While this phase change can be repeated multiple times, heating the gel past its consolidation temperature, typically above 130 °C, initiates an irreversible reaction that produces highly crosslinked glassy organic/inorganic materials via hydrolysis and polycondensation. This ability makes melting gels uniquely compatible with processing techniques inaccessible to other sol-gels. By properly tuning their properties, it should be possible to create protective coatings for electronics and anti-corrosive coatings for metals that are highly hydrophobic and insulating. However, melting gel consolidation reactions are highly dependent on charge interactions, raising the question of how these materials will respond to a processing technique, like electrospray deposition (ESD), which is dependent on charge delivery. In this study, we focus on the role that substrate temperature and charge polarity play on film morphology, consolidation chemistry, and surface properties when processing via ESD. Optical images, film thickness measurements, and FTIR were used to characterize the sprayed melting gel with the goal of developing a robust processing space for producing highly cross linked, hydrophobic, dielectric coatings.

Robustness versus Performance Assessment for Different Gamma-TiAl Processing Routes

2011 ◽  
Vol 1295 ◽  
Author(s):  
Marc Thomas
Keyword(s):  
High Performance ◽  
Cost Effective ◽  
Processing Route ◽  
Transportation Industry ◽  
Tial Alloys ◽  
Alternative Processing ◽  
Aerospace Applications ◽  
Robust Processing ◽  
Processing Techniques ◽  
Robust Process

ABSTRACTOne of the main driving force for the development of advanced structural materials is weight saving especially in the transportation industry in order to reduce CO2 emission. The utilization of gamma aluminides, as good candidates for aerospace applications, is strongly related to the development of a cost-effective and robust processing route, as far as possible. It is well established that the processing route, i.e. cast, wrought or PM, has a dramatic effect on the microstructure and texture of gamma-TiAl alloys. Therefore, significant microstructural variations through post-heat treatments coupled with compositional modifications can only guarantee a proper balance of desired properties. However, a number of metallurgical factors during the processing steps can contribute to some scattering in properties. This review will highlight several critical process variables in terms of the resulting g-TiAl microstructures. Of primary importance is the as-cast texture which is difficult to control and may contribute to prefer some alternative processing routes to ensure a better repeatability in mechanical results. Some innovative processing techniques for controlling the structure will then be presented. The main point which will be discussed in this paper is whether an approach leading to a robust process would not be at the expense of the high performance of the structural material.

Processing Techniques of a Silicon Carbide Heat Exchanger and its Capable Properties – A Review

2015 ◽  
Vol 787 ◽  
pp. 513-517 ◽  
Author(s):  
R. Pachaiyappan ◽  
R. Gopinath ◽  
S. Gopalakannan
Keyword(s):  
Silicon Carbide ◽  
Heat Exchanger ◽  
Gas Turbines ◽  
Cooling System ◽  
Composite Ceramic ◽  
Processing Technique ◽  
Full Potential ◽  
Absorption Chillers ◽  
Evaporative Cooling System ◽  
Processing Techniques

Silicon carbides is a composite ceramic material produced from inorganic non-metallic substances, formed from the molten mass which solidifies on cooling and simultaneously matured by the action of heat. It is used in various applications such as grinding wheels, filtration of gases and water, absorption, catalyst supports, concentrated solar powers, thermoelectric conversion etc. The modern usage of silicon carbide is fabricated as a heat exchanger for high temperature applications. Leaving behind steel and aluminium, silicon carbide has an excellent temperature withstanding capability of 1425°C. It is resistant to corrosion and chemical erosion. Modern fusion reactors, Stirling cycle based gas turbines, evaporators in evaporative cooling system for air condition and generator in LiBr/H2O absorption chillers for air conditioning those systems heat transfer rate can be improved by replacing a present heat exchanger with silicon carbide heat exchanger. This review presents a detailed discussion about processing technique of such a silicon carbide. Modern known processing techniques are partial sintering, direct foaming, replica, sacrificial template and bonding techniques. The full potential of these materials can be achieved when properties are directed over specified application. While eyeing over full potential it is highly dependent on processing techniques.

scholarly journals Current understanding and applications of the cold sintering process

2019 ◽  
Vol 13 (4) ◽  
pp. 654-664 ◽  
Author(s):  
Tong Yu ◽  
Jiang Cheng ◽  
Lu Li ◽  
Benshuang Sun ◽  
Xujin Bao ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Sintering Temperature ◽  
Applied Pressure ◽  
Processing Technique ◽  
Rechargeable Batteries ◽  
Processing Conditions ◽  
Ceramic Processing ◽  
Sintering Process ◽  
Novel Processing ◽  
Processing Techniques

Abstract In traditional ceramic processing techniques, high sintering temperature is necessary to achieve fully dense microstructures. But it can cause various problems including warpage, overfiring, element evaporation, and polymorphic transformation. To overcome these drawbacks, a novel processing technique called “cold sintering process (CSP)” has been explored by Randall et al. CSP enables densification of ceramics at ultra-low temperature (⩽300°C) with the assistance of transient aqueous solution and applied pressure. In CSP, the processing conditions including aqueous solution, pressure, temperature, and sintering duration play critical roles in the densification and properties of ceramics, which will be reviewed. The review will also include the applications of CSP in solid-state rechargeable batteries. Finally, the perspectives about CSP is proposed.

scholarly journals Spatial Enhancement of AWiFS along Wider Swath using NSCT

2018 ◽  
Vol 7 (3.12) ◽  
pp. 474
Author(s):  
K S. R. Radhika ◽  
C V. Rao ◽  
V Kamakshi Prasad
Keyword(s):  
Temporal Resolution ◽  
Accuracy Assessment ◽  
Super Resolution ◽  
Computation Time ◽  
Processing Technique ◽  
Sensor Data ◽  
Liss Iii ◽  
Novel Processing ◽  
Single Image Super Resolution ◽  
Processing Techniques

Image acquisition in a wider swath, cannot assess the best spatial resolution (SR) and temporal resolution (TR) simultaneously, due to inherent limitations of space borne sensors. But any of the information extraction from remote sensed (RS) images demands the above characteristics. As this is not possible onboard, suitable ground processing techniques need to be evolved to realise the requirements through advanced image processing techniques. The proposed work deals with processing of two onboard sensor data viz., Resourcesat-1 (RS1): LISS-III, which has medium swath combined with AWiFS, which has wider swath data to provide high spatial and temporal resolution at the same instant. LISS-III at 23m and 24 days, AWiFS at 56m and 5 days spatial and temporal revisits acquire the data at different swaths. In the process of acquisition at the same time, the 140km swath of LISS-III coincides at the exact centre line 740km swath of AWiFS. If the non-overlapping area of AWiFS has same features of earth’s surface as of LISS-III overlapping area, it then provides a way to increase the SR of AWiFS to SR of LISS-III in the same non-overlapping area. Using this knowledge, a novel processing technique Fast One Pair Learning and Prediction (FOPLP) is developed in which time is optimized against the existing methods. FOPLP improves the SR of LISS-III in non-overlapping area using technique Single Image Super Resolution (SISR) with Non Sub sampled Contourlet Transforms (NSCT) method and is applied on different sets of images. The proposed technique resulting into an image having TR of 5 days, 740km swath at SR of 23m. Results have shown the strength of the proposed method in terms of computation time and prediction accuracy assessment.  

INTEX pour l’annotation semi-automatique d’un corpus d’anaphores

1999 ◽  
Vol 22 (1-2) ◽  
pp. 173-189
Author(s):  
Agnès Tutin
Keyword(s):  
Syntactic Processing ◽  
Text Generation ◽  
Grammatical Function ◽  
Linguistic Features ◽  
Processing Stage ◽  
Language Understanding ◽  
Anaphoric Pronouns ◽  
Robust Processing ◽  
Processing Techniques ◽  
Automatic Text

Anaphors constitute a well-known problem in automatic text generation and natural language understanding. Using corpora to deal with such phenomena could help to develop robust processing techniques. Building such resources is, though, a tedious and time-consuming task and could more easily be accomplished by partial automation. In this paper, we show how the intex system can be used for this task. We show that in a newspaper corpus (in this case, le Monde Diplomatique), discursive grammatical anaphors can easily be located via associated linguistic features. A series of transducers generating tags for categories and functions can thus be built, and constitutes an efficient pre-processing stage (though manual checking remains necessary). The heuristics, quickly and easily developed, are specific to the task. The study goes on to show, however, that discarding non-anaphoric pronouns is not straightforward in the case of non-referential personal pronouns or indefinite pronouns, and that the tagging of the grammatical function seems limited in the absence of real syntactic processing.

Solving Time Complexity Issue in Copy-Move Forgery Detection Thru Pre-processing Techniques

2018 ◽  
Vol 8 (3) ◽  
Author(s):  
Siti Fadzlun Md Salleh ◽  
Mohd Foad Rohani ◽  
Mohd Aizaini Maarof Maarof
Keyword(s):  
Time Complexity ◽  
Processing Technique ◽  
Experimental Result ◽  
Discrete Wavelet ◽  
Detection Accuracy ◽  
Forgery Detection ◽  
Complexity Issue ◽  
Processing Step ◽  
Copy Move Forgery Detection ◽  
Processing Techniques

Copy-move forgery detection (CMFD) has become a popular an important research focus in digital image forensic. Copy-move forgery happens when a region in an image is copied and paste into the same image. Apart from the main problem of detection robustness and accuracy, CMFD is struggle with time complexity issue. One of the options to resolve this problem was by including pre-processing step in CMFD pipeline. This paper reviews on the importance of pre-processing step, and available techniques in reducing time complexity of copy-move forgery detection. An experiment using discrete wavelet transform (DWT) as a pre-processing technique was carried out to evaluate the performance of adopting pre-processing technique in CMFD pipeline. The experimental result has shown a significant reduction in processing time with some trade off to detection accuracy.

The Data Processing Technique of Metallic Sheet Friction Coefficient Determination

2012 ◽  
Vol 184-185 ◽  
pp. 688-691
Author(s):  
Huan Xue ◽  
Rong Feng Li ◽  
Hong Chuan Zhu
Keyword(s):  
Data Processing ◽  
Coefficient Of Friction ◽  
Normal Pressure ◽  
Processing Technique ◽  
Test Results ◽  
Friction Zone ◽  
Data Processing Method ◽  
The Coefficient Of Friction ◽  
Processing Techniques ◽  
Metallic Sheet

The definition and research background of friction is introduced. The reason of generation of friction is analyzed, the importance of the coefficient of friction test in sheet metal forming field is indicated. The testing principle of coefficient of friction on metallic sheet is presented. The basic data processing method of the test is described. Two important data processing techniques which will obviously effects the test results, including effective friction zone and normal pressure have been carefully studied. The comparison result shows these techniques can effectively enhance the testing stability and precision.

The Application of Signal Processing Techniques in Improving Spectrometer Detection Limit

2011 ◽  
Vol 148-149 ◽  
pp. 1045-1050
Author(s):  
Zhi Ying Wu ◽  
Yi Zhang ◽  
Zuo Yuan Shen
Keyword(s):  
Signal Processing ◽  
Detection Limit ◽  
High Sensitivity ◽  
Processing Technique ◽  
Laser Source ◽  
Sampled Data ◽  
High Concentration ◽  
Signal Processing Technique ◽  
Processing Techniques ◽  
Lock In

Improving spectrometer detection limit using statistical principle and signal-processing technique are described simply in this work. In the detection of gas photoacoustic(PA) signal, accurate partitions of the sampled data affect on the detection limit to some extent although Lock-in amplification technique with high SNR and microphone sensor with high sensitivity have been used. A model and the resulting algorithm are proposed from PA-signal samples. The techniques are validated at ppb level on PA spectrometer for NH3 breath detection in high concentration of CO2 and H2O based on tunable erbium-doped fiber laser (TEDFL) or for multicomponent trace gas detection based on waveguide CO2 laser or on other laser source.

MATLAB Image Processing as a Viable Tool to Study Low Surface Roughness

2015 ◽  
Author(s):  
Wesley S. Hunko ◽  
Vishnuvardhan Chandrasekaran ◽  
Lewis N. Payton
Keyword(s):  
Image Processing ◽  
Surface Roughness ◽  
Standard Deviation ◽  
Data Acquisition ◽  
Processing Technique ◽  
Image Processing Technique ◽  
Polished Surface ◽  
Digital Microscope ◽  
A New Technique ◽  
Processing Techniques

The purpose of this paper is to present the results of a study comparing an old technique for measuring low surface roughness with a new technique of data acquisition and processing that is potentially cheaper, quicker and more automated. It offers the promise of in-process quality monitoring of surface finish. Since the late 1800s, researchers have investigated the light scattering effects of surface asperities and have developed many interferometry techniques to quantify this phenomenon. Through the use of interferometry, the surface roughness of objects can be very accurately measured and compared. Unlike contact measurement such as profilometers, interferometry is nonintrusive and can take surface measurements at very wide ranges of scale. The drawbacks to this method are the high costs and complexity of data acquisition and analysis equipment. This study attempts to eliminate these drawbacks by developing a single built-in MATLAB function, to simplify data analysis, and a very economically priced digital microscope (less than $200), for data acquisition. This is done by comparing the results of various polishing compounds on the basis of the polished surface results obtained from MATLAB’s IMHIST function to the results of stylus profilometry methods. The study with the MATLAB method is also to be compared to 3D microscopy with a Keyence microscope. With surface roughness being a key component in many manufacturing and tribology applications, the apparent need for accurate, reliable and economical measuring systems is prevalent. However, interferometry is not a cheap or simple process. “Over the last few years, advances in image processing techniques have provided a basis for developing image-based surface roughness measuring techniques” [1]. One popular image processing technique is through the use of MATLAB’s Image Processing Toolbox. This includes an array of functions that can be used to quantify and compare textures of a surface. Some of these include standard deviation, entropy, and histograms of images for further analysis. “These statistics can characterize the texture of an image because they provide information about the local variability of the intensity values of pixels in an image. For example, in areas with smooth texture, the range of values in the neighborhood around a pixel will be a small value; in areas of rough texture, the range will be larger. Similarly, calculating the standard deviation of pixels in a neighborhood can indicate the degree of variability of pixel values in that region” [2]. By combining the practices of interferometry with the processing techniques of MATLAB, this fairly new method of roughness measurement proved itself as a very viable and inexpensive technique. This technique should prove to be a very viable means of interferometry at an affordable cost.

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