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Topic Review
Industrial Effluent and Sludge Toxicity
Industrial effluents and sludges are among the most critical sources of highly polluted and contaminated residues and can cause many environmental and ecological issues upon discharge to the environment. A comprehensive scientometric analysis has been carried out in this study to provide a clear understanding of the scientific efforts regarding the analysis of industrial effluents’ toxicity assessment. India and the USA accounted as the leading countries contributing the most in this regard by evaluating and analyzing the industrial effluent to avoid environmental contamination.
  • 1.8K
  • 06 Sep 2021
Topic Review
Discovery and Development of Non-nucleoside Reverse-transcriptase Inhibitors
Non-nucleoside reverse-transcriptase inhibitors (NNRTIs) are antiretroviral drugs used in the treatment of human immunodeficiency virus (HIV). NNRTIs inhibit reverse transcriptase (RT), an enzyme that controls the replication of the genetic material of HIV. RT is one of the most popular targets in the field of antiretroviral drug development. Discovery and development of NNRTIs began in the late 1980s and in the end of 2009 four NNRTI had been approved by regulatory authorities and several others were undergoing clinical development. Drug resistance develops quickly if NNRTIs are administered as monotherapy and therefore NNRTIs are always given as part of combination therapy, the highly active antiretroviral therapy (HAART).
  • 1.8K
  • 09 Nov 2022
Topic Review
TiO2-Based Nanostructures for Microbial Inactivation
Pathogenic microorganisms can spread throughout the world population, as the current COVID-19 pandemic has dramatically demonstrated. In this scenario, a protection against pathogens and other microorganisms can come from the use of photoactive materials as antimicrobial agents able to hinder, or at least limit, their spreading by means of photocatalytically assisted processes activated by light—possibly sunlight—promoting the formation of reactive oxygen species (ROS) that can kill microorganisms in different matrices such as water or different surfaces without affecting human health. Here, we focus the attention on TiO2 nanoparticle-based antimicrobial materials, intending to provide an overview of the most promising synthetic techniques, toward possible large-scale production, critically review the capability of such materials to promote pathogen (i.e., bacteria, virus, and fungi) inactivation, and, finally, take a look at selected technological applications.
  • 1.7K
  • 08 Dec 2020
Topic Review
Carbon Nanotubes
Carbon nanotubes are a quasi-one-dimensional nanomaterial having excellent compatibility with cementitious material. Recently several research carried out utilising different types of Carbon nanotubes (Single wall carbon nanotube, multiwall carbon nanotube, -COOH and -OH functionalised carbon nanotube etc.) to investigate its influences in terms of flowability, microstructure, mechanical, and durability properties. CNT is chemically inert material but addition of small doses of CNTs can significantly improve the mechanical and microstructural properties of concrete/cementitious composites. CNT act as nucleating agents and promote the higher growth of C-S-H. However, improvement of mechanical, microstructural  and durability properties depends on CNTs concentration, physical properties and type of CNTs. 
  • 1.7K
  • 27 Oct 2020
Topic Review
Review of Ionic Liquids Toxicity
Ionic liquids (more accurately room-temperature ionic liquids (RTILs)) can be defined as materials composed of organic or inorganic cations (like imidazolium or pyridinium) and anions (e.g., nitrate, acetate, tetrafluoroborate, dicyanamide, bis(trifluoromethylsulfonyl)imide and lactate) that are liquid at or below 100 °C. The number of possible combinations of a cation and anion is estimated to reach 106, making it theoretically possible to synthesize an IL targeted for a specific application or property.
  • 1.7K
  • 29 Jun 2021
Topic Review
InN SAs for Ultrafast Lasers
New fabrication methods are strongly demanded for the development of thin-film saturable absorbers with improved optical properties (absorption band, modulation depth, nonlinear optical response). In this sense, we investigate the performance of indium nitride (InN) epitaxial layers with low residual carrier concentration (<1018 cm^-3), which results in improved performance at telecom wavelengths (1560 nm). These materials have demonstrated a huge modulation depth of 23% and a saturation fluence of 830 uJ/cm2, and a large saturable absorption around -3 x10^4 cm/GW has been observed, attaining an enhanced, nonlinear change in transmittance. We have studied the use of such InN layers as semiconductor saturable absorber mirrors (SESAMs) for an erbium (Er)-doped fiber laser to perform mode-locking generation at 1560 nm. We demonstrate highly stable, ultrashort (134 fs) pulses with an energy of up to 5.6 nJ.a
  • 1.7K
  • 01 Dec 2020
Topic Review
Interaction of Water and Solutes
Water plays an important role in chemical and biological processes. The interaction of water and solutes is of great significance for understanding the properties of aqueous solutions or bio-systems.
  • 1.7K
  • 08 Feb 2022
Topic Review
Optimizing Sustainability Opportunities for Biochar
Biochar is most commonly considered for its use as a soil amendment, where it has gained attention for its potential to improve agricultural production and soil health. Twenty years of near exponential growth in investigation has demonstrated that biochar does not consistently deliver these benefits, due to variables in biochar, soil, climate, and cropping systems. While biochar can provide agronomic improvements in marginal soils, it is less likely to do so in temperate climates and fertile soils. Here, biochar and its coproducts may be better utilized for contaminant remediation or the substitution of nonrenewable or mining-intensive materials. 
  • 1.7K
  • 18 Oct 2021
Topic Review
High-Entropy Alloys
Microstructural phase evolution during melting and casting depends on the rate of cooling, the collective mobility of constituent elements, and binary constituent pairs. Parameters used in mechanical alloying and spark plasma sintering, the initial structure of binary alloy pairs, are some of the factors that influence phase evolution in powder-metallurgy-produced HEAs. Factors such as powder flowability, laser power, powder thickness and shape, scan spacing, and volumetric energy density (VED) all play important roles in determining the resulting microstructure in additive manufacturing technology. Large lattice distortion could hinder dislocation motion in HEAs, and this could influence the microstructure, especially at high temperatures, leading to improved mechanical properties in some HEAs. Mechanical properties of some HEAs can be influenced through solid solution hardening, precipitation hardening, grain boundary strengthening, and dislocation hardening. Despite the HEA system showing reliable potential engineering properties if commercialized, there is a need to examine the effects that processing routes have on the microstructure in relation to mechanical properties. 
  • 1.7K
  • 09 Jun 2021
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.
  • 1.7K
  • 27 Aug 2020
Topic Review
3D Printing to Produce BioComposite
Current environmental concerns have led to a search of more environmentally friendly manufacturing methods, thus, natural fibers have gained attention in the 3D printing industry to be used as biofilters along with thermoplastics. The utilization of natural fibers is very convenient as they are easily available, cost-effective, eco-friendly, and biodegradable. Using natural fibers rather than synthetic fibers in the production of the 3D printing filaments will reduces gas emissions associated with the production of the synthetic fibers that would add to the current pollution problem. As a matter of fact, natural fibers have a reinforcing effect on plastics. This review analyzes how the properties of the different types of polymers vary when natural fibers processed to produce filaments for 3D Printing are added. The results of using natural fibers for 3D Printing are presented in this study and appeared to be satisfactory, while a limited number of studies have reported some issues.
  • 1.7K
  • 13 May 2021
Topic Review
Strain Gradient Plasticity Theories (SGPT)
SGTs are featured with the introduction of one or more scale lengths in the model used to describe the medium behavior.  Among all the SGTs, those that make use of the gradient of the plastic part of the strain are called Strain Gradient Plasticity Theories (SGPT).
  • 1.7K
  • 23 Sep 2020
Topic Review
Chemical Explosive
The vast majority of explosives are chemical explosives. Explosives usually have less potential energy than fuels, but their high rate of energy release produces a great blast pressure. TNT has a detonation velocity of 6,940 m/s compared to 1,680 m/s for the detonation of a pentane-air mixture, and the 0.34-m/s stoichiometric flame speed of gasoline combustion in air. The properties of the explosive indicate the class into which it falls. In some cases explosives can be made to fall into either class by the conditions under which they are initiated. In sufficiently large quantities, almost all low explosives can undergo a Deflagration to Detonation Transition (DDT). For convenience, low and high explosives may be differentiated by the shipping and storage classes.
  • 1.7K
  • 01 Nov 2022
Topic Review
Extended Characteristic Polynomial
In the context of molecular topology it is well known the Characteristic Polynomial (ChP) for its important uses in relating the structure with molecular properties of hydrocarbons, as well as a high resolution discriminant for chemical structures. Also it is well known that, as any other topological based descriptor/function, the ChP is blind to the nature of the chemical element and of the chemical bond, both being treated as indistinguishable in the context of the chemical graphs theory. An extension of the Characteristic Polynomial (EChP) is proposed by relaxing the identity matrix and adjacency matrix to contain non-binary based values, by in the same time keeping the meaning of those matrices (identity as collecting information regarding the identity of the atoms in the molecule and adjacency as collecting information regarding the connectivity or bonds in the molecule) and their feature (of being symmetrical).
  • 1.6K
  • 29 Oct 2020
Topic Review
Zn-Pb Metallurgical Slags as Source of Metal Recovery
The mineralogical and chemical characteristics of zinc and lead smelting slags are presented, with particular reference to the slags formed during the simultaneous production of Zn and Pb by the Imperial Smelting Process. These slags, because of the presence of many metals in their composition, mainly in the form of crystalline phases, are a valuable source for their extraction. Slags from Zn-Pb metallurgy are processed on an industrial scale using pyrometallurgical and hydrometallurgical methods, alongside which a number of experiments conducted to recover metals as efficiently as possible, including bioleaching experiments.
  • 1.6K
  • 03 Jan 2024
Topic Review
Magnetic Materials for Electrical Machines
Additive manufacturing has many advantages over traditional manufacturing methods and has been increasingly used in medical, aerospace, and automotive applications. The flexibility of additive manufacturing technologies to fabricate complex geometries from copper, polymer, and ferrous materials presents unique opportunities for new design concepts and improved machine power density without significantly increasing production and prototyping cost. Topology optimization investigates the optimal distribution of single or multiple materials within a defined design space, and can lead to unique geometries not realizable with conventional optimization techniques. As an enabling technology, additive manufacturing provides an opportunity for machine designers to overcome the current manufacturing limitation that inhibit adoption of topology optimization. Successful integration of additive manufacturing and topology optimization for fabricating magnetic components for electrical machines can enable new tools for electrical machine designers. This article presents a comprehensive review of the latest achievements in the application of additive manufacturing, topology optimization, and their integration for electrical machines and their magnetic components.
  • 1.6K
  • 25 Feb 2021
Topic Review
Precipitation
In an aqueous solution, precipitation is the process of transforming a dissolved substance into an insoluble solid from a super-saturated solution. The solid formed is called the precipitate. In case of an inorganic chemical reaction leading to precipitation, the chemical reagent causing the solid to form is called the precipitant. The clear liquid remaining above the precipitated or the centrifuged solid phase is also called the 'supernate' or 'supernatant'. The notion of precipitation can also be extended to other domains of chemistry (organic chemistry and biochemistry) and even be applied to the solid phases (e.g., metallurgy and alloys) when solid impurities segregate from a solid phase.
  • 1.6K
  • 07 Nov 2022
Topic Review
SPE influence on GTEs coatings
Solid particles erosion (SPE) has and is still one of the main challenges that faces the gas turbine engines (GTE) industry, especially when such systems are utilized in harsh environments. This is because the impingement mechanism of the particles on the blades surface causes them to structurally deform, and hence the system performance gets degraded continuously with the operational lifetime. In order to reduce the impact caused by SPE on gas turbines, it is crucial to know before hands the surrounding environment in which the system will be operating, clearly understand how SPE mechanism behaves with different surface materials, select the appropriate blade material that can balance between the performance of the GTE and SPE resistance, and more advance cases use surface coatings.
  • 1.6K
  • 27 Oct 2020
Topic Review
Cyclodextrins
Cyclodextrins (CDs) are a family of cyclic oligosaccharides artificially obtained from the union of glucose monomers linked by α-1,4 glycosidic bonds. They are shaped as truncated cones due to the constitutional asymmetry of the glucopyranose rings. Their central cavity of the cone is lined with the skeletal carbons and ethereal oxygen of the glucose residues, which produce a hydrophobic zone that is capable of forming inclusion complexes with a variety of molecules. For this reason, a number of CDs have become everyday commodities in separation sciences, and so chemical aspects such as their structures or their intercalation mode have been more profoundly studied. The structural aspects of CDs can enable the improvement of different chromatographic separations, the enhancement of sensitivity, and the accuracy of analytical methods. 
  • 1.6K
  • 08 Jan 2021
Topic Review
Date Rape Drug
A date rape drug is any drug that incapacitates another person and renders that person vulnerable to sexual assault, including rape. The substances are associated with date rape because of reported incidents of their use in the context of two people dating, during which the victim is sexually assaulted or raped or suffers other harm. The substances are not exclusively used to perpetrate sexual assault or rape, but are the properties or side-effects of substances normally used for legitimate medical purposes. One of the most common incapacitating agents for date rape is alcohol, administered either surreptitiously or consumed voluntarily, rendering the victim unable to make informed decisions or give consent.
  • 1.6K
  • 04 Nov 2022
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