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Topic Review
Cement Asphalt Emulsion Mortar Composites
CA mortar (sometimes abbreviated to CAM) is one of the major construction materials for slab ballastless track in high-speed railways; it is an intermediate layer flung within the space between the track slab and the trackbed (as depicted in) of CRTS I and CRTS II. Cement and asphalt mortar is an organic–inorganic composite material primarily composed of asphalt emulsion, cement, sand, water, and other chemical admixtures. This composite material possesses fascinating properties that are different from both concrete and asphalt material alone because it couples the strength of cement as well as the flexibility of asphalt material.
  • 1.1K
  • 03 Nov 2021
Topic Review
Cross-Coupling-Reaction of Copper Carbene Intermediate with Terminal Alkyne
Copper-catalyzed cross-coupling reaction of a copper carbene intermediate with terminal alkynes was one of the most powerful protocols for the construction of C–C bonds. However, in early works, a mixture of alkynoates and allenoates was generated in combined moderate yields under harsh reaction conditions. Until 2004, Fu reported the first example of the copper-catalyzed coupling reaction of terminal alkynes with diazo esters or diazo amides to yield 3-alkynoate or 3-butynamide products selectively with minimal amount of allene byproducts under no-basic conditions. Consequently, a variety of copper-catalyzed coupling reactions of terminal alkynes with various carbene precursors have been developed independently.
  • 1.1K
  • 30 May 2022
Topic Review
Thia-Michael Reaction
While the Michael addition has been employed for more than 130 years for the synthesis of a vast diversity of compounds, the reversibility of this reaction when heteronucleophiles are involved has been generally less considered. First applied to medicinal chemistry, the reversible character of the hetero-Michael reactions has been explored for the synthesis of Covalent Adaptable Networks (CANs), in particular the thia-Michael reaction and more recently the aza-Michael reaction. In these cross-linked networks, exchange reactions take place between two Michael adducts by successive dissociation and association steps. In order to understand and precisely control the exchange in these CANs, it is necessary to get an insight into the critical parameters influencing the Michael addition and the dissociation rates of Michael adducts by reconsidering previous studies on these matters. 
  • 1.1K
  • 28 Nov 2022
Topic Review
Strychnine Poisoning
Strychnine poisoning can be fatal to humans and other animals and can occur by inhalation, swallowing or absorption through eyes or mouth. It produces some of the most dramatic and painful symptoms of any known toxic reaction, making it quite noticeable and a common choice for assassinations and poison attacks. For this reason, strychnine poisoning is often portrayed in literature and film, such as the murder mysteries written by Agatha Christie. The probable lethal oral dose in humans is 1.5 to 2 mg/kg. Similarly, the median lethal dose for dogs, cats, and rats ranges from 0.5 to 2.35 mg/kg.
  • 1.1K
  • 01 Dec 2022
Topic Review
Reactions of Nitrile Anions
Nitrile anions are the conjugate bases of alkyl nitriles. They undergo nucleophilic addition and substitution reactions with various electrophiles.
  • 1.1K
  • 24 Oct 2022
Topic Review
Application of Two-Dimensional Materials towards CMOS-Integrated Gas Sensors
The semiconductor metal oxide (SMO)-based gas sensor, considered the current workhorse of semiconductor-based chemiresistive gas sensor technologies, requires high temperatures to initiate the surface reactions which result in the sensing response, making it difficult to fabricate and prone to high mechanical instability. Therefore, alternatives at lower temperatures are desired, where 2D materials seem to hold the most promise. Even at ambient temperature, their sensitivity is extraordinarily large due to their extremely high surface-to-volume ratio. However, some ongoing issues still need to be resolved before gas sensors based on 2D materials can be widely used and commercialized. The alternative room temperature solutions involve optical signals, either by designing an nondispersive infrared (NDIR) sensor based on the Beer-Lambert law or by introducing an additional UV illumination to SMO sensors. In both cases, complementary metal oxide semiconductor (CMOS) integration is not feasible, which is why continued interest in 2D-material-based gas sensors persists.
  • 1.1K
  • 02 Dec 2022
Topic Review
Iron Oxide Nanoparticles
Iron oxide nanoparticles (IONs) have shown promising potential as delivery vehicles and cellular markers for theranostic applications. Their high biocompatibility, superparamagnetic properties and exceptional surface-coating versatility have facilitated the development of IONs that adequately interact with biological environments. The strategical modification of ION architectures towards performing highly specialized functions has allowed the rational design of next-generation nanoparticles for biomedical applications.
  • 1.1K
  • 07 Jan 2021
Topic Review
Waste Derivatives in Drilling Fluids
The increased production of waste materials is a significant concern due to their effect on public health and the environment. Mismanagement of food waste, in particular, has become a major global issue, thus prompting the need for better solutions that use these materials in different applications. Among various applications, food waste can be considered to be a sustainable alternative for additives in drilling fluids used in the oil and gas drilling industry. Chemical additives to drilling fluids are necessary components to facilitate drilling operations by enhancing the fluids’ properties, including rheology and filtrate loss. Studies have demonstrated that waste-derived materials, including food waste, have the potential to provide an environmentally safe alternative to toxic conventional chemical additives used in water-based drilling fluids. 
  • 1.1K
  • 17 Aug 2021
Topic Review
PbS Quantum Dot Solar Cells
PbS (lead sulfide) colloidal quantum dots consist of crystallites with diameters in the nanometer range with organic molecules on their surfaces, partly with additional metal complexes as ligands. These surface molecules are responsible for solubility and prevent aggregation, but the interface between semiconductor quantum dots and ligands also influences the electronic structure. PbS quantum dots are especially interesting for optoelectronic applications and spectroscopic techniques, including photoluminescence, photodiodes and solar cells.
  • 1.1K
  • 12 Sep 2020
Topic Review
Microbially-Induced Desaturation and Carbonate Precipitation
Microbially induced carbonate precipitation (MICP) has been proposed as a sustainable approach to solve various environmental, structural, geotechnical and architectural issues. In the last decade, a ubiquitous microbial metabolism, nitrate reduction (also known as denitrification) got attention in MICP research due to its unique added benefits such as simultaneous corrosion inhibition in concrete and desaturation of porous media. The latter even upgraded MICP into a more advanced concept called microbially induced desaturation and precipitation (MIDP) which is being investigated for liquefaction mitigation.
  • 1.1K
  • 01 Sep 2021
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