Topic Review
Applications of Liquid Crystals-Based Sensors
Liquid crystals are a class of chemical substances that exist in intermediate states between crystalline solids and liquids. They thus share the anisotropic properties of crystalline solids as well as fluid properties of isotropic liquids. 
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  • 23 Mar 2022
Topic Review
Applications of Luminescent Materials in Visible Light Communication
The growing demand for faster data transference and communication allowed the development of faster and more efficient communication network-based technologies, with wider bandwidth capability, high resilience to electromagnetic radiation, and low latency for information travelling. To provide a suitable alternative to satisfy data transmission and consumption demand, wireless systems were established after studies on this topic. Visible light communication (VLC) processes were incorporated as interesting wireless approaches that make use of a wide frequency communication spectrum to reach higher bandwidth values and accelerate the speed of data/information transmission. For this aim, light converters, such as phosphor materials, are reported to efficiently convert blue light into green, yellow, and red emissions; however, long carrier lifetimes are achieved to enlarge the frequency bandwidth, thereby delaying the data transference rate.
  • 284
  • 28 Jun 2023
Topic Review
Applications of Metal–Organic Frameworks
Metal–organic frameworks (MOFs) have been broadly applied to numerous domains with a substantial surface area, tunable pore size, and multiple unsaturated metal sites. Hollow MOFs and their composites as well as their applications can be used in organic catalysis, electrochemical sensing, and adsorption separation.
  • 377
  • 06 Jan 2023
Topic Review
Aptamer-Sensors for Quantification of AFB1
Aflatoxin B1 (AFB1) is one of the most frequently-found mycotoxins in contaminated food. As the content of mycotoxins is particularly low in food, the development of probes to detect AFB1 in foods with high sensitivity and selectivity is an urgent social need for the evaluation of food quality. Numerous techniques have been developed to monitor AFB1. Nevertheless, most of them require cumbersome, labor-consuming, and sophisticated instruments, which have limited their application. An aptamer is a single, short nucleic acid sequence that is capable of recognizing different targets. Owing to their unique properties, aptamers have been considered as alternatives to antibodies. Aptasensors are considered to be an emerging strategy for the quantification of aflatoxin B1 with high selectivity and sensitivity. 
  • 715
  • 19 Oct 2020
Topic Review
Aromatic Water Pollutants
In recent years, the intensification of human activities including rapid urbanization, industrialization, population, and economic growth, led to an increase in waste production and energy demand. Most importantly such activities pose concerns for health, energy security and climate changes. Hazardous volatile organic compounds, VOC, and aromatic organic compounds, AOC, are being generated from the activities of many vital industries like mining and petrochemicals. They are instrumental in the economic growth of many countries and their products are regarded as privileges to modern communities. Nevertheless, they are toxic and carcinogenic thus, these wastes have been classified as “hazardous”. The simultaneous treatment of organic pollutants and energy recovery is an attractive solution to reduce pollution in water, air, and soil as well as provide alternative clean energy sources. Hydrogen could be generated from organic pollutants in water through photocatalysis. Photocatalysis refers to the oxidation and reduction, redox, reactions on semiconductor surfaces, mediated by the valence band holes and conduction band electrons, which are generated by the absorption of ultraviolet or visible light radiation. Compared to traditional oxidation processes, photocatalytic redox reaction operates at ambient conditions without a high temperature or high pressure, and many recalcitrant organic contaminants can be degraded without the addition of chemical oxidants, hence it is fully green process. Among the various photocatalysts, TiO2, as the most widely employed “golden” photocatalyst, has been largely used in photocatalysis, due to its chemical stability, nontoxicity, and low cost. In the last two decades, TiO2 photocatalysis has expanded very quickly, having undergone various development‐related energy issues and environmental issues, such as direct solar H2O splitting into H2 and the decomposition of pollutants in air and H2O at low concentrations. Although great progress has been made in TiO2 photocatalysis, much remains unknown, which raises an interesting challenge not only for engineers but also for basic scientists. a typical photocatalytic reaction in TiO2 photocatalysis contains many fundamental processes, including charge carrier formation, separation, relaxation, trapping, transfer, recombination, and transportation.
  • 1.7K
  • 24 May 2021
Topic Review
Array-Based Cell Sensing for Chemical Screening
Synthetic chemicals are widely used in the daily life, making chemical safety assessments necessary for environmental exposure. Additionally, the rapid determination of chemical drug efficacy and safety is a key step in therapeutic discoveries. Cell-based screening methods are non-invasive, and cellular phenotypic changes can also provide more sensitive indicators of chemical effects than conventional cell viability. Array-based cell sensors can be engineered to maximize sensitivity to changes in cell phenotypes, lowering the threshold for detecting cellular responses under external stimuli. Therefore, array-based sensing can provide a robust strategy for both cell-based chemical risk assessments and therapeutics discovery.
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  • 06 Apr 2022
Topic Review
Atomic Layer Deposition on 2D Materials
Atomic layer deposition (ALD) of high-κ dielectrics on two-dimensional (2D) materials (including graphene and transition metal dichalcogenides) still represents a challenge due to the lack of out-of-plane bonds on the pristine surfaces of 2D materials, thus making the nucleation process highly disadvantaged. The typical methods to promote the nucleation (i.e., the predeposition of seed layers or the surface activation via chemical treatments) certainly improve the ALD growth but can affect, to some extent, the electronic properties of 2D materials and the interface with high-κ dielectrics. Hence, direct ALD on 2D materials without seed and functionalization layers remains highly desirable. In this context, a crucial role can be played by the interaction with the substrate supporting the 2D membrane. In particular, metallic substrates such as copper or gold have been found to enhance the ALD nucleation of Al2O3 and HfO2 both on monolayer (1 L) graphene and MoS2. Similarly, uniform ALD growth of Al2O3 on the surface of 1 L epitaxial graphene (EG) on SiC (0001) has been ascribed to the peculiar EG/SiC interface properties.
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  • 15 Dec 2021
Topic Review
Basic Principles of COF-Based Sensing
Covalent organic frameworks (COFs) are a class of crystalline porous organic polymers with polygonal porosity and highly ordered structures. The most prominent feature of the COFs is their excellent crystallinity and highly ordered modifiable one-dimensional pores. Since the first report of them in 2005, COFs with various structures were successfully synthesized and their applications in a wide range of fields including gas storage, pollution removal, catalysis, and optoelectronics explored. In the meantime, COFs also exhibited good performance in chemical and biological sensing, because their highly ordered modifiable pores allowed the selective adsorption of the analytes, and the interaction between the analytes and the COFs’ skeletons may lead to a detectable change in the optical or electrical properties of the COFs.
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  • 17 May 2022
Topic Review
Binders Used for the Manufacturing of Composite Materials
Binders, or tackifiers, have become widespread in the production of new composite materials by liquid composite molding (LCM) techniques due to their ability to stabilize preforms during laying-up and impregnation, as well as to improve fracture toughness of the obtained composites, which is very important in aviation, automotive, ship manufacturing, etc. Furthermore, they can be used in modern methods of automatic laying of dry fibers into preforms, which significantly reduces the labor cost of the manufacturing process.
  • 2.9K
  • 19 Jan 2022
Topic Review
Bio-Coatings Methods for Fruits and Vegetables Preservation
Consuming fresh food is undoubtedly the best way to enjoy various flavors and nutrients, but their preservation helps to enjoy all these even out of season. Bio-coating technologies hold great promise for the future of food preservation, offering a more sustainable and healthy way to keep fruits and vegetables fresh for more extended periods. The choice of a coating method may depend on the type of fresh fruits and vegetables, the coating material, and the desired coating thickness. The application method should be carried out under hygienic conditions to prevent contamination and ensure the effectiveness of the coating. It is also essential to apply the coating evenly and that it adheres properly to the surface of the produce, maximizing its effectiveness. The coating material can be applied in its pure form or mixed with other ingredients such as antioxidants, preservatives, or antimicrobial agents, thus enhancing its effectiveness.
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  • 16 Aug 2023
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