Topic Review
Ultrasonic dynamic mechanical analysis (UDMA) for polymer characterization
Ultrasonic wave propagation has been used for the high frequency dynamic mechanical analysis of polymers with the aim to monitor the changes of viscoelastic properties in polymers associated with glass transition, crystallization, physical or chemical gelation, crosslinking, and curing reactions.
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  • 11 Jun 2020
Topic Review
Printed Electronics
Printed electronics are manufactured in a process of registering thin functional material (ink) layer combinations on a low-cost substrate that may be recycled and/or naturally degraded in nature. Correspondingly, the manufacturing process is composed of three complementary stages: material selection, printing and post-printing. The materials for the printed electronics are principally inks of conducting, semiconducting or dielectric characteristics and substrates, which are derived from synthetic or natural polymers.  The inks are transferred with a master through direct contact to the substrate in case of contact printing, while they are deposited onto the substrate typically through nozzles in case of non-contact printing. Posterior to the printing process, it is often necessary to conduct sintering/curing in order to reach the desired functional ink and substrate characteristics. The inks, substrate and the printing technology along with the post printing requirements must be carefully evaluated for quality, repeatability and life-time aspects of the yield.
  • 1.1K
  • 23 Aug 2021
Topic Review
1,3-Butadiene
1,3-Butadiene is the organic compound with the formula (CH2=CH)2. It is a colorless gas that is easily condensed to a liquid. It is important industrially as a monomer in the production of synthetic rubber. The molecule can be viewed as the union of two vinyl groups. It is the simplest conjugated diene. Although butadiene breaks down quickly in the atmosphere, it is nevertheless found in ambient air in urban and suburban areas as a consequence of its constant emission from motor vehicles. The name butadiene can also refer to the isomer, 1,2-butadiene, which is a cumulated diene with structure H2C=C=CH−CH3. This allene has no industrial significance.
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  • 17 Oct 2022
Topic Review
Application of Laser-Induced Periodic Surface Structures (LIPSS)
As a laser technology, the femtosecond laser is used in biomedical fields due to its excellent performance—its ultrashort pulses, high instantaneous power, and high precision. As a surface treatment process, the femtosecond laser can prepare different shapes on metal surfaces to enhance the material’s properties, such as its wear resistance, wetting, biocompatibility, etc. Laser-induced periodic surface structures (LIPSSs) are a common phenomenon that can be observed on almost any material after irradiation by a linearly polarized laser. Surface texturing by laser irradiation can change various materials’ properties and create multifunctional surfaces. Materials can be better applied by customizing functional surfaces.
  • 1.1K
  • 04 Nov 2022
Topic Review
The Medicinal Chemistry of Artificial Nucleic Acids
Nucleic acids play a central role in human biology, making them suitable and attractive tools for therapeutic applications. While conventional drugs generally target proteins and induce transient therapeutic effects, nucleic acid medicines can achieve long-lasting or curative effects by targeting the genetic bases of diseases.
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  • 05 Aug 2022
Topic Review
MOF-based adsorbents for atmospheric emission
This topic focuses on the use of metal–organic frameworks (MOFs) for adsorbing gas species that are known to weaken the thermal self-regulation capacities of Earth’s atmosphere. A large section is dedicated to the adsorption of carbon dioxide, while another section is dedicated to the adsorption of other different gas typologies, whose emissions, for various reasons, represent a “wound” for Earth’s atmosphere. High emphasis is given to MOFs that have moved enough ahead in their development process to be currently considered as potentially usable in “real-world” (i.e., out-of-lab) adsorption processes. As a result, there is strong evidence of a wide gap between laboratory results and the industrial implementation of MOF-based adsorbents. Indeed, when a MOF that performs well in a specific process is commercially available in large quantities, economic observations still make designers tend toward more traditional adsorbents. Moreover, there are cases in which a specific MOF remarkably outperforms the currently employed adsorbents, but it is not industrially produced, thus strongly limiting its possibilities in large-scale use. To overcome such limitations, it is hoped that the chemical industry will be able to provide more and more mass-produced MOFs at increasingly competitive costs in the future.
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  • 27 Aug 2020
Topic Review
Mushroom Poisoning
Mushroom poisoning is poisoning resulting from the ingestion of mushrooms that contain toxic substances. Its symptoms can vary from slight gastrointestinal discomfort to death in about 10 days. Mushroom toxins are secondary metabolites produced by the fungus. Mushroom poisoning is usually the result of ingestion of wild mushrooms after misidentification of a toxic mushroom as an edible species. The most common reason for this misidentification is a close resemblance in terms of color and general morphology of the toxic mushrooms species with edible species. To prevent mushroom poisoning, mushroom gatherers familiarize themselves with the mushrooms they intend to collect, as well as with any similar-looking toxic species. The safety of eating wild mushrooms may depend on methods of preparation for cooking.
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  • 19 Oct 2022
Topic Review
Concrete Incorporated with Recycled HDPE
Incorporating recycled plastic waste in concrete manufacturing is one of the most ecologically and economically sustainable solutions for the rapid trends of annual plastic disposal and natural resource depletion worldwide. This paper comprehensively reviews the literature on engineering performance of recycled high-density polyethylene (HDPE) incorporated in concrete in the forms of aggregates or fiber or cementitious material. Optimum 28-days’ compressive and flexural strength of HDPE fine aggregate concrete is observed at HDPE-10 and splitting tensile strength at HDPE-5 whereas for HDPE coarse aggregate concrete, within the range of 10% to 15% of HDPE incorporation and at HDPE-15, respectively. Similarly, 28-days’ flexural and splitting tensile strength of HDPE fiber reinforced concrete is increased to an optimum of 4.9 MPa at HDPE-3 and 4.4 MPa at HDPE-3.5, respectively, and higher than the standard/plain concrete matrix (HDPE-0) in all HDPE inclusion levels. Hydrophobicity, smooth surface texture and non-reactivity of HDPE has resulted in weaker bonds between concrete matrix and HDPE and thereby reducing both mechanical and durability performances of HDPE concrete with the increase of HDPE.
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  • 07 Jun 2021
Topic Review
Agouti (Gene)
The agouti gene encodes the agouti-signaling protein (ASIP), responsible for the distribution of melanin pigment in mammals. Agouti interacts with the melanocortin 1 receptor to determine whether the melanocyte (pigment cell) produces phaeomelanin (a red to yellow pigment), or eumelanin (a brown to black pigment). This interaction is responsible for making distinct light and dark bands in the hairs of animals such as the agouti. In other species such as horses, the agouti gene is responsible for determining which parts of the body will be black. Horses can either have black distributed across its body or can have black only in certain locations such as the tail, ears, mane, and the lower legs. In mice, the agouti gene determines whether the animal will be yellow or grey and brown. The agouti-signaling protein (ASIP) is a competitive antagonist with alpha-Melanocyte-stimulating hormone (α-MSH) to bind with melanocortin 1 receptor (MC1R) proteins. Activation by α-MSH causes production of the darker eumelanin, while activation by ASIP causes production of the redder phaeomelanin. This means that if agouti is expressed then the phenotype will be yellow and if it's not expressed then the phenotype would be grey.
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  • 08 Nov 2022
Topic Review
Metallophthalocyanines
Since the serendipitous discovery of phthalocyanines (Pcs), at the beginning of the 20th century, growing attention has been devoted to the ubiquitous catalytic properties and applications of Pcs and Pcs coordinated with metal ions, Metallophthalocyanines (MPcs). In fact, these old synthetic dyes have been very attractive in the view of academic research, but mainly for catalytic industrial purposes as these dyes are easily accessible on a large scale, are robust under harsh reaction conditions, show high activity, and can be recovered and recycled. The success and diversity of MPcs as catalysts over different substrates are mostly attributed to their high structural flexibility in terms of metals and electronic properties of the phthalocyanine ligands.
  • 1.1K
  • 20 Feb 2021
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