scholarly journals Carbon-Based Materials for Humidity Sensing: A Short Review

Micromachines ◽  
2019 ◽  
Vol 10 (4) ◽  
pp. 232 ◽  
Author(s):  
Jean-Marc Tulliani ◽  
Barbara Inserra ◽  
Daniele Ziegler
Keyword(s):  
Water Content ◽  
Flexible Electronics ◽  
Short Review ◽  
Industrial Applications ◽  
Humidity Sensors ◽  
Humidity Sensing ◽  
Carbon Soot ◽  
Pros And Cons ◽  
Materials Used ◽  
Air Conditioning Systems

Humidity sensors are widespread in many industrial applications, ranging from environmental and meteorological monitoring, soil water content determination in agriculture, air conditioning systems, food quality monitoring, and medical equipment to many other fields. Thus, an accurate and reliable measurement of water content in different environments and materials is of paramount importance. Due to their rich surface chemistry and structure designability, carbon materials have become interesting in humidity sensing. In addition, they can be easily miniaturized and applied in flexible electronics. Therefore, this short review aims at providing a survey of recent research dealing with carbonaceous materials used as capacitive and resistive humidity sensors. This work collects some successful examples of devices based on carbon nanotubes, graphene, carbon black, carbon fibers, carbon soot, and more recently, biochar produced from agricultural wastes. The pros and cons of the different sensors are also discussed in the present review.

Development of Nanomaterials as Photo Catalysts for Environmental Applications

2020 ◽  
Vol 09 ◽  
Author(s):  
Ahmed M. Abu-Dief ◽  
W. S. Mohamed
Keyword(s):  
Water Purification ◽  
Smart Materials ◽  
Block Size ◽  
Industrial Applications ◽  
Vital Role ◽  
High Catalytic Activity ◽  
Chemical Contaminants ◽  
Environmental Threats ◽  
Photo Catalysis ◽  
Materials Used

Abstract:: Sustainability environmental lack is a growing and pivotal mater due to the issues: such as disturbances associated with biodiversity pollution, and climate change. Pollutants are the major cause of these environmental threats in the atmosphere. In recently, the nano-based photocatalyst is at the forefront of the author's interest because of its promising potential as a green chemical-based compound, high catalytic activity, the suitable and controllable surface area for wastewater treatment. Semiconductor materials in nanosized scale have electronic and optical properties depend on its building block size, which plays a vital role in developing smart materials that are well efficient for simultaneously destroying harmful chemical contaminants from our environment. This makes these materials used in many possible industrial applications such as water purification. In this Review, we report the most significant results contributing to progress in the area of environmental hazardous pollutant detection and removal focused on water purification especially through photo-catalysis to give readers an overview of the present research trends. Moreover, we analyze previous studies to indicate key principles of photo-catalysis and provide guidelines that can be used to fabricate more efficient photocatalysts.

scholarly journals Promising Immobilization of Industrial-Class Phospholipase A1 to Attain High-Yield Phospholipids Hydrolysis and Repeated Use with Optimal Water Content in Water-in-Oil Microemulsion Phase

2021 ◽  
Vol 11 (4) ◽  
pp. 1456
Author(s):  
Yusuke Hayakawa ◽  
Ryoichi Nakayama ◽  
Norikazu Namiki ◽  
Masanao Imai
Keyword(s):  
Water Content ◽  
Reaction Rate ◽  
Enzyme Reaction ◽  
Initial Reaction Rate ◽  
Industrial Applications ◽  
Molar Ratio ◽  
High Yield ◽  
Initial Reaction ◽  
Phospholipase A1 ◽  
Repeated Use

In this study, we maximized the reactivity of phospholipids hydrolysis with immobilized industrial-class phospholipase A1 (PLA1) at the desired water content in the water-in-oil (W/O) microemulsion phase. The optimal hydrophobic-hydrophilic condition of the reaction media in a hydrophobic enzyme reaction is critical to realize the maximum yields of enzyme activity of phospholipase A1. It was attributed to enzymes disliking hydrophobic surroundings as a special molecular structure for reactivity. Immobilization of PLA1 was successfully achieved with the aid of a hydrophobic carrier (Accurel MP100) combination with the treatment using glutaraldehyde. The immobilized yield was over 90% based on simple adsorption. The hydrolysis reaction was kinetically investigated through the effect of glutaraldehyde treatment of carrier and water content in the W/O microemulsion phase. The initial reaction rate increased linearly with an increasing glutaraldehyde concentration and then leveled off over a 6% glutaraldehyde concentration. The initial reaction rate, which was predominantly driven by the water content in the organic phase, changed according to a typical bell-shaped curve with respect to the molar ratio of water to phospholipid. It behaved in a similar way with different glutaraldehyde concentrations. After 10 cycles of repeated use, the reactivity was well sustained at 40% of the initial reaction rate and the creation of the final product. Accumulated yield after 10 times repetition was sufficient for industrial applications. Immobilized PLA1 has demonstrated potential as a biocatalyst for the production of phospholipid biochemicals.

Micro-Ribbons and Micro-Wires Silica Synthesis Using Bottom-Top Technique

2020 ◽  
Vol 1008 ◽  
pp. 33-38
Author(s):  
Marwa Nabil ◽  
Hussien A. Motaweh
Keyword(s):  
Selection Process ◽  
Chemical Properties ◽  
Industrial Applications ◽  
Preparation Process ◽  
Pure Silica ◽  
One Step ◽  
Materials Used ◽  
Sonication Technique ◽  
Silica Synthesis ◽  
Physical And Chemical

Silica is one of the most important materials used in many industries. The basic factor on which the selection process depends is the structural form, which is dependent on the various physical and chemical properties. One of the common methods in preparing pure silica is that it needs more than one stage to ensure the preparation process completion. The goal of this research is studying the nucleation technique (Bottom-top) for micro-wires and micro-ribbons silica synthesis. The silica nanoand microstructures are prepared using a duality (one step); a combination of alkali chemical etching process {potassium hydroxide (3 wt %) and n-propanol (30 Vol %)} and the ultra-sonication technique. In addition, the used materials in the preparation process are environmentally friendly materials that produce no harmful residues. The powder product is characterized using XRD, FTIR, Raman spectrum and SEM for determining the shape of architectures. The most significant factor of the nucleation mechanism is the sonication time of silica powder production during the dual technique. The product stages are as follows; silica nanoparticles (21-38 nm), nanoclusters silica (46 – 67 nm), micro-wires silica (1.17 – 6.29 μm), and micro-ribbons silica (19.4 – 54.1 μm). It's allowing for use in environmental applications (multiple wastewater purification, multiple uses in air filters, as well as many industrial applications).

Memory Devices Based on Solid Electrolytes

2007 ◽  
Vol 997 ◽  
Author(s):  
Michael N Kozicki
Keyword(s):  
Data Storage ◽  
Solid Electrolytes ◽  
Short Review ◽  
High Resistivity ◽  
Material System ◽  
Resistance Change ◽  
Technology Roadmap ◽  
Conducting Pathway ◽  
Significant Research ◽  
Materials Used

AbstractCurrent mainstream memory technologies are unlikely to completely fulfill the solid state data storage requirements that will be imposed beyond the 32 nm node of the International Technology Roadmap for Semiconductors. One potential replacement technology is resistance change memory based on solid electrolytes and a number of significant research and development efforts are already underway. The lowering of the resistance is attained by the reduction of ions in a relatively high resistivity electrolyte to form a conducting bridge between the electrodes. The resistance is returned to the high value via the application of a reverse bias that results in the breaking of the conducting pathway. Germanium chalcogenides and Ag-Ge-S ternaries in particular possess good thermal processing characteristics while maintaining the necessary high ion mobility for rapid switching. Thermally diffused copper in deposited SiO2 also is of interest, as thermal stability in excess of 600°C and commonly used constituents makes this material system compatible with the widest range of back-end-of-line processes. This paper details some of the developments in the understanding of the materials used in solid electrolyte resistance change devices and presents a short review of the electrical characteristics of devices based on Ag-Ge-S and Cu-Si-O electrolytes.

An investigation on the possibility to improve the corrosion and cavitation resistance of SS304 steel by NiTi coatings

2021 ◽  
Vol 35 (04) ◽  
pp. 2150057
Author(s):  
Qunfeng Zeng ◽  
Khashayar Khanlari ◽  
Naiming Lin
Keyword(s):  
Wear Resistance ◽  
Corrosion Resistance ◽  
Niti Alloy ◽  
Preliminary Investigation ◽  
Industrial Applications ◽  
Cavitation Resistance ◽  
Niti Alloys ◽  
Materials Used ◽  
Ss 304 ◽  
Increasing Load

Equiatomic and near equiatomic NiTi alloys, showing good mechanical and thermal shape memory properties, are widely exploited in different industrial applications. In addition, NiTi alloys have promising anti-cavitation and corrosion-resistance properties. These advantages have provided opportunities to exploit NiTi alloys as the coatings for protecting materials used in the industrial applications. This study is a preliminary investigation aiming to evaluate the feasibility to form NiTi alloy coatings on SS304 steel by tungsten inert argon arc welding (TIG) technology. The microstructure analysis shows that the crystalline phases in NiTi coatings on SS 304 steel are TiNi-B2, TiNi-B19’ and Ni3Ti. The potential of the NiTi coatings to enhance the corrosion resistance and cavitation resistance behaviors of steel exposed to seawater is studied. NiTi coatings, with two different thicknesses of about 1.2 and 2 mm, having homogenous microstructures were successfully deposited on SS304 steel using TIG technology. Results of tests, done in aqueous solutions simulating seawater, showed that the formation of the oxide films on the surface of NiTi coatings increased the corrosion resistance and wear resistance and decreased the damage caused by the cavitation. Moreover, it was understood that the NiTi coatings with 2 mm in thickness show the superior performances than those with 1.2 mm in thickness. The tribological mechanisms responsible for the unique properties of NiTi alloy coatings were investigated. The wear-resistance behaviors of NiTi alloy coatings are greatly influenced by the friction conditions. Increasing load decreased CoF and the wear rate of the coatings were almost constant, which was attributed to the pseudoelasticity of NiTi alloy. The attractive properties of NiTi alloys that makes it most influential materials for industrial applications have also been discussed.

Fabrication of bulk alumina structures with humidity sensing capabilities using direct ink write technique

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Anabel Renteria ◽  
Luisa F. Garcia ◽  
Jorge A. Diaz ◽  
Luis C. Delfin ◽  
Jaime E. Regis ◽  
...  
Keyword(s):  
Humidity Sensor ◽  
Post Processing ◽  
Humidity Sensors ◽  
Moisture Sensitivity ◽  
Humidity Sensing ◽  
Content Type ◽  
Lattice Design ◽  
Processing Treatment ◽  
Binder Ratio ◽  
Order Of Magnitude

Purpose The purpose of this study is to evaluate different 3D structures for humidity sensing that will enable the fabrication of complex geometries with high moisture sensitivity. Design/methodology/approach Humidity sensors based on alumina ceramics were fabricated using direct ink write (DIW) technique. Different engineered surface area, polymer binder ratio and post-processing treatment were considered to increase moisture sensitivity. Findings It was found that the binder ratio plays an important role in controlling the rheology of the paste during printing and determining the pore size after post-processing treatment. The sensibility of the fabricated humidity sensor was investigated by measuring its capacitance response toward relative humidity (RH) varying from 40% to 90% RH at 25°C. It is shown that using 3D lattice design, printed alumina humidity sensor could improve sensitivity up to 31.6 pF/RH%, over an order of magnitude higher than solid alumina. Originality/value Most of the alumina humidity sensors available are films in nature because of manufacturing difficulties, which limited its potential of higher sensitivity, and thus broader applications. In this paper, a novel 3D alumina humidity sensor was fabricated using DIW 3D printing technology.

scholarly journals Industrial applications of laser-induced breakdown spectroscopy: a review

2020 ◽  
Vol 12 (8) ◽  
pp. 1014-1029 ◽  
Author(s):  
S. Legnaioli ◽  
B. Campanella ◽  
F. Poggialini ◽  
S. Pagnotta ◽  
M. A. Harith ◽  
...  
Keyword(s):  
Short Review ◽  
Industrial Applications ◽  
Laser Induced Breakdown Spectroscopy ◽  
Breakdown Spectroscopy ◽  
Laser Induced Breakdown

A short review on LIBS industrial applications.

scholarly journals Colorectal cancer screening and prevention—pros and cons

2019 ◽  
Vol 12 (3) ◽  
pp. 239-243 ◽  
Author(s):  
Markus Niederreiter ◽  
Lukas Niederreiter ◽  
Andreas Schmiderer ◽  
Herbert Tilg ◽  
Angela Djanani
Keyword(s):  
Colorectal Cancer ◽  
Short Review ◽  
Premalignant Lesions ◽  
Screening Programs ◽  
Randomized Controlled ◽  
Randomized Controlled Studies ◽  
Incidence And Mortality ◽  
Screening Strategies ◽  
Pros And Cons ◽  
Screening Procedures

Summary Colorectal cancer (CRC) is one of the most frequent cancer entities worldwide and a leading cause of death. The disease is known to develop from potentially curable, premalignant lesions over several years and therefore is suitable for screening procedures and preventive measures. Several trials have demonstrated reduced incidence and mortality in screening cohorts. A multitude of different screening strategies for CRC have been implemented in different parts of the world. While randomized controlled studies directly comparing screening procedures are still ongoing, colonoscopy remains the gold standard for screening and the only procedure that allows to effectively prevent CRC by treating premalignant lesions. However, population-wide participation rates vary greatly but often only reach approximately 25%. Noninvasive screening strategies are indispensable to increase acceptance rates and for resource-limited regions with limited capacity for colonoscopy. Importantly, while incidence of CRC increases with age, lately we have seen a raise in incidence for CRC in the population below 50 years of age, potentially requiring to include younger adults (e.g., 45 years of age) into established screening programs. It remains important to continue to gather data and evidence regarding effectiveness of various screening strategies, preferably in randomized controlled trials. This short review will outline currently established screening procedures and will discuss the pros and cons for each individual approach.

scholarly journals Waste Electrical and Electronic Equipment: A Review on the Identification Methods for Polymeric Materials

Recycling ◽  
2019 ◽  
Vol 4 (3) ◽  
pp. 32 ◽  
Author(s):  
Grigorescu ◽  
Grigore ◽  
Iancu ◽  
Ghioca ◽  
Ion
Keyword(s):  
Polymeric Materials ◽  
Industrial Applications ◽  
Complete Characterization ◽  
Electronic Equipment ◽  
Raw Material ◽  
Identification Methods ◽  
Material Resources ◽  
Characteristic Values ◽  
Materials Used

Considering that the large quantity of waste electrical and electronic equipment plastics generated annually causes increasing environmental concerns for their recycling and also for preserving of raw material resources, decreasing of energy consumption, or saving the virgin materials used, the present challenge is considered to be the recovery of individual polymers from waste electrical and electronic equipment. This study aims to provide an update of the main identification methods of waste electrical and electronic equipment such as spectroscopic fingerprinting, thermal study, and sample techniques (like identification code and burning test), and the characteristic values in the case of the different analyses of the polymers commonly used in electrical and electronic equipment. Additionally, the quality of the identification is very important, as, depending on this, new materials with suitable properties can be obtained to be used in different industrial applications. The latest research in the field demonstrated that a complete characterization of individual WEEE (Waste Electric and Electronic Equipment) components is important to obtain information on the chemical and physical properties compared to the original polymers and their compounds. The future directions are heading towards reducing the costs by recycling single polymer plastic waste fractions that can replace virgin plastic at a ratio of almost 1:1.

scholarly journals Paper-Based ZnS:Cu Alternating Current Electroluminescent Devices for Current Humidity Sensors with High–Linearity and Flexibility

Sensors ◽  
2019 ◽  
Vol 19 (21) ◽  
pp. 4607 ◽  
Author(s):  
Yaqin He ◽  
Mengyao Zhang ◽  
Nan Zhang ◽  
Danrong Zhu ◽  
Chun Huang ◽  
...  
Keyword(s):  
Humidity Sensor ◽  
Silver Nanowires ◽  
Alternating Current ◽  
Sensor Technology ◽  
Sensing Element ◽  
Humidity Sensors ◽  
Phosphor Layer ◽  
Humidity Sensing ◽  
Electroluminescent Devices ◽  
Sensing Mechanism

Humidity sensors are indispensable for various electronic systems and instrumentations. To develop a new humidity sensing mechanism is the key for the next generation of sensor technology. In this work, a novel flexible paper-based current humidity sensor is proposed. The developed alternating current electroluminescent devices (ACEL) consist of the electroless plating Ni on filter paper and silver nanowires (AgNWs) as the bottom and upper electrodes, and ZnS:Cu as the phosphor layer, respectively. The proposed humidity sensor is based on ACEL with the paper substrate and the ZnS:Cu phosphor layer as the humidity sensing element. The moisture effect on the optical properties of ACELs has been studied firstly. Then, the processing parameters of the paper-based ACELs such as electroless plated bottom electrode and spin-coated phosphor layer as a function of the humidity-sensitive characteristics are investigated. The sensing mechanism of the proposed sensor has been elucidated based on the Q ~ V analysis. The sensor exhibits an excellent linearity ( R 2 = 0.99965 ) within the humidity range from 20% to 90% relative humidity (RH) and shows excellent flexibility. We also demonstrate its potential application in postharvest preservation where the EL light is used for preservation and the humidity can be monitored simultaneously through the current.

Sign in / Sign up

Export Citation Format

Share Document