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1 – 8 of 8Qijing Lin, Zirong Wu, Na Zhao, Zhuangde Jiang, Qidong Zhang, Bian Tian and Peng Shi
The Fabry-Perot sapphire optical fiber sensor is an excellent choice for high-temperature sensing in civil and military fields, such as oil exploitation, engine and turbine. The…
Abstract
Purpose
The Fabry-Perot sapphire optical fiber sensor is an excellent choice for high-temperature sensing in civil and military fields, such as oil exploitation, engine and turbine. The purpose of this paper is to study the high-reflective film system withstanding high temperature in Fabry-Perot sapphire optical fiber high-temperature sensor. To improve the performance of the sensor and reduce the difficulty of signal acquisition, one of the key ways is to enhance the normalized light intensity of F-P sensor, which can be achieved by coating the high-reflective film system on the fiber end.
Design/methodology/approach
The high-reflective film system can be achieved by a multilayer film with alternating ZrO2 and Al2O3 film layers whose refractive indexes are different. In addition, the optimum film alternating sequences and the influence of the number of film layers, incident angle and temperature should be obtained by numerical analysis.
Findings
With the increase of the number of film layers, the reflectivity rises gradually and the change trend is more and more gentle. A minimum of the spectral reflectivity will occur at a certain incident angle depending on the design of the periodic multilayer system. Temperature affects the reflectivity of high-reflective film system. The normalized light intensity of the F-P sensor coated with high-reflective film system enhances greatly which is helpful to the signal demodulation. The temperature response of the F-P sensor is mainly determined by the characteristics of the F-P cavity.
Originality/value
Higher reflectivity, lower cost and easy signal acquisition are the most important features of the introduced high-reflective film system for the Fabry-Perot sapphire optical fiber high-temperature sensor.
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Z.H.Z. Abidin, N.S.A. Manah, A.N. Hadi, N.S. Saugi, F.A. Fuad, N.A. Mazni, H.C. Hassan, M.A. Careem and A.K. Arof
This paper aims to focus on a comparison study of the visible stability of natural blue dye consisting anthocyanin molecules extracted from Clitoria ternatea in coating films.
Abstract
Purpose
This paper aims to focus on a comparison study of the visible stability of natural blue dye consisting anthocyanin molecules extracted from Clitoria ternatea in coating films.
Design/methodology/approach
The coating films were prepared by mixing the blue dye with poly(acrylamide-co-acrylic acid) in three different weight ratios. Samples were coded as 10PBA, 15PBA and 20PBA, where PBA is the abbreviation for poly acrylamide-co-acrylic acid, blue dyes and anthocyanin. The number at the beginning of each code represents the weight percentage of poly(acrylamide-co-acrylic acid) to natural blue dye. The mixtures were applied on separate glass substrates to form coating films. Another set of samples were prepared for the comparison study with a commercial acrylic clear coat (cc) applied on the surface of the 10PBA, 15PBA and 20PBA coating films. These coating films were coded 10PBAcc, 15PBAcc and 20PBAcc. The purpose of the clear coat is to observe how it affects the colour stability of the blue coating films with respect to time. All samples were exposed to the ultraviolet (UV) source, an 18 W Philips TL-D 18w/830 UV fluorescent lamp. The UV lamp was placed 15 cm above the surface of the samples for 35 days. The colour of the coatings was measured using CIE L*a*b* colour space coordinate.
Findings
The results obtained show 10PBA and 10PBAcc have the highest colour stability after 35 days of exposure to UV light. The reflectivity of the coating films was also measured during exposure to UV lamp. Reflectivity measurements also showed that 10PBA and 10PBAcc coating films had the highest reflective stabilities.
Research limitations/implications
The potential of using natural blue dye consisting anthocyanin in coating film to obtain high colour stability.
Practical implications
The coating film developed in this work is suitable to be applied on glass substrates.
Originality/value
The application of anthocyanin dye extracted from the Clitoria ternatea L. as a colourant in coating films
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Porismita Borah and Kyle John Lorenzano
Purpose: The main purpose of the study is to understand the factors that facilitate correction behavior among individuals. In this study the authors examine the impact of…
Abstract
Purpose
Purpose: The main purpose of the study is to understand the factors that facilitate correction behavior among individuals. In this study the authors examine the impact of self-perceived media literacy (SPML) and reflection on participants’ correction behavior.
Design/methodology/approach
Methods: Data for the study were collected from Amazon's MTurk using an online survey. Data were collected after a certificate of exemption was received by the Institutional Review Board in a research university in the United States (US) Qualtrics software was used to collect data. The total number of participants was 797.
Findings
Findings: The findings show that although both SPML and reflection are positively associated with rumor refutation, higher SPML alone is not enough. Reflective judgment is critical for individuals to take part in this behavior online, such that individuals with higher reflective judgment indicated that they refute rumors online, irrespective of their SPML score.
Originality/value
Originality: The authors tested the relationship of multiple variables with participants correction behavior. Although research shows the importance of social correction, there is not much knowledge about what facilitates actual misinformation correction.
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Sebastian Löffler, Christopher Mauermann, Angela Rebs and Günter Reppe
The purpose of the paper is to show up the current possibilities by combination of classic thick-film technology with advanced processing. Thick-film hybrid ceramic substrates…
Abstract
Purpose
The purpose of the paper is to show up the current possibilities by combination of classic thick-film technology with advanced processing. Thick-film hybrid ceramic substrates have been a base for highly reliable devices for space, aerospace, medical and industrial applications since many years. The combination of classic thick-film printing with advanced technologies for fine line structuring provides substrates best suited for packaging solutions with challenging requirements, such as temperature stability and extended product lifetime. Combined with state of the art assembly technologies, thick-film substrates are used in highly demanding industries.
Design/methodology/approach
In recent years, several technologies for fine line structuring have been introduced, e.g. fine line printing, photo imaging, etching, laser structuring for local chip fan-out or fine line structuring on single layers. For further miniaturization of thick-film multilayers circuits, after solving the fine line resolution, the reduction of electrical connection of conductive layers through printed insulation/dielectric layer (via) diameters to connect the layers should be addressed.
Findings
The focus of this paper is to show the results of combining fine line structuring with laser microvias and to compare laser drilling in thick-films with different established via forming technologies.
Originality/value
The reduction of via size to 60 µm – smaller than 50% compared to using state-of-the-art printing technologies enables a solution for significant relaxation of current design possibilities.
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Owing to the technology growth, especially in Microsystems technology and Nanotechnology, new products will provide new ways to sense variables that are crucial for product…
Abstract
Purpose
Owing to the technology growth, especially in Microsystems technology and Nanotechnology, new products will provide new ways to sense variables that are crucial for product improvement and system reliability. A big concern of the scientific community is the measurement of low level flow measurements, especially for the biomedical and/or systems on a chip approaches.Design/methodology/approach – A new flow meter concept design consists of a surface micromachined sensor having an optical high reflective mirror made of gold, which is attached to unique cantilever designs that bend due to the drag force of mass flow. The bending of the cantilevers produces the mirror to approach/depart from an optical fiber end‐tip. The reflective light to fiber is modulated using a Fabry‐Perot interferometry technique to determine the mirror separation to the fiber, which corresponds to the mass flow.Findings – The new concept design shows a big potential approach to measure low flow measurements for air, gas and liquids of low viscosity. The results of this concept, through finite element analysis, show that the material used to build the sensor, makes them excellent candidates for fabrication. The stresses of the materials and allowable (readable) bending are among the tolerances of such materials/construction‐design. The sensor is not affected by electromagnetic interference and does not require electrical currents to sense, i.e. it is perfectly suited for biomedical and low mass‐flow sensing such as lab‐on‐chip applications.Originality/value – Among all approaches to sense low flow measurements, most of them need either “big” turbine approaches (dimensions over 1 cm diameter), or the need of an electrical approach needed in the end measurement sensor. This work proposes a non‐electrical approach.
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Amirul Syafiq, Lilik Jamilatul Awalin, Syukri Ali and Mohd Arif
The paper aims to design the optimum formulation of the nano-titanium dioxide (TiO2) hydrophilic coating system using the synthetic polypropylene glycol (PPG), which can create…
Abstract
Purpose
The paper aims to design the optimum formulation of the nano-titanium dioxide (TiO2) hydrophilic coating system using the synthetic polypropylene glycol (PPG), which can create the reflection and absorption property.
Design/methodology/approach
TiO2 nanoparticles are used as fillers, and PPG has been blended at the proper ratio of 1PPG: 0.2TiO2. The prepared resin has been applied onto the glass substrate at different numbers of glass immersions during the dip-coating fabrication process. One-time glass immersion is labeled as T1 coating, two-time glass immersion is labeled as T2 coating and three-time glass immersion is labeled as T3 coating. All the prepared coating systems were left dry at ambient temperature.
Findings
T3 coating showed the lowest reading of WCA value at 40.50°, due to higher surface energy at 61.73 mN/m. The T3 coating also shows the greatest absorbance property among the prepared coating systems among the prepared coating. In terms of reflectance property, the T2 coating system has great reflectance in UV region and near-infrared region, which is 16.47% and 2.77 and 2.73%, respectively. The T2 coating also has great optical transmission about 75.00% at the visible region.
Research limitations/implications
The development of thermal insulation coating by studying the relationship between convection heat and reflectance at different wavelengths of incident light.
Practical implications
The developed coating shows high potential for glass window application.
Originality/value
The application of the hydrophilic coating on light absorption, reflectance and transmission at different wavelengths.
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Qing Jiang, Yuhang Wan, Xiaoqian Li, Xueru Qu, Shengnan Ouyang, Yi Qin, Zhenyu Zhu, Yushu Wang, Hualing He and Zhicai Yu
This study aims to evaluate the thermal performance of sodium alginate (SA) aerogel attached to nano SiO2 and its radiative cooling effect on firefighting clothing without…
Abstract
Purpose
This study aims to evaluate the thermal performance of sodium alginate (SA) aerogel attached to nano SiO2 and its radiative cooling effect on firefighting clothing without environmental pollution.
Design/methodology/approach
SA/SiO2 aerogel with refractory heat insulation and enhanced radiative cooling performance was fabricated by freeze-drying method, which can be used in firefighting clothing. The microstructure, chemical composition, thermal stability, and thermal emissivity were analyzed using Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analyzer and infrared emissivity measurement instrument. The radiative cooling effect of aerogel was studied using thermal infrared imager and thermocouple.
Findings
When the addition of SiO2 is 25% of SA, the prepared aerogel has excellent heat insulation and a high radiative cooling effect. Under a clear sky, the temperature of SA/SiO2 aerogel is 9.4°C lower than that of pure SA aerogel and 22.1°C lower than that of the simulated environment. In addition, aerogel has more exceptional heat insulation effect than other common fabrics in the heat insulation performance test.
Research limitations/implications
SA/SiO2 aerogel has passive radiative cooling function, which can efficaciously economize global energy, and it is paramount to environment-friendly cooling.
Practical implications
This method could pave the way for high-performance cooling materials designed for firefighting clothing to keep maintain the wearing comfort of firefighters.
Originality/value
SA/SiO2 aerogel used in firefighting clothing can release heat to the low-temperature outer space in the form of thermal radiation to achieve its own cooling purpose, without additional energy supply.
Graphical abstract
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Syed Hammad Mian, Mohammed Abdul Mannan and Abdulrahman M. Al-Ahmari
The purpose of this paper is to investigate the influence of surface topology on the performance of laser line scanning probe and to suggest methodology for 3D digitization of…
Abstract
Purpose
The purpose of this paper is to investigate the influence of surface topology on the performance of laser line scanning probe and to suggest methodology for 3D digitization of specular surfaces.
Design/methodology/approach
Two different molds, one having milled surface and the other with polished surface, were used to identify effect of surface characteristics on the performance of laser line scanning probe mounted on bridge-type coordinate measuring machine. The point cloud data acquisition of two surfaces was carried out using different combinations of laser scanning parameters. The point cloud sets thus obtained were analyzed in terms of completeness, noise and accuracy. The polished mold which exhibited specular reflection was digitized at different scanning angles of laser line scanning probe using the best combination of scanning parameters.
Findings
Results confirmed that surface characteristics play important role to determine quality of the reverse engineering (RE) process. The results in terms of completeness, accuracy and noise for point cloud sets have successfully been obtained for milled and polished surfaces. Three-dimensional (3D) comparison analysis suggested larger deviation in cases of polished surface as compared to milled surface. The point cloud set acquired with proposed approach was better in terms of both completeness and noise reduction.
Originality/value
There has been an increased demand for measurement of metallic, polished and shiny surfaces in automotive, aerospace and medical industries. These surfaces are very difficult to scan because they exhibit specular reflection instead of diffuse reflection. Laser line scanning probe which is a non-contact method is in great demand for RE. This is due to the fact that it possesses very high data acquisition speed. However, laser scanning is hugely affected by surface characteristics which in turn govern specular reflection.In this paper, it has been shown that a surface that exhibits various degrees of specular reflection can be digitized efficiently if appropriate combination of scanning parameters and positions of laser line scanning probe are used. Also, this paper has attempted to offer a procedure to overcome incompleteness and noise in 3D data as obtained by the laser line scanning probe.
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