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Topic Review
Classification of the Approved EGFR-TKIs
Targeting EGFR with small-molecule inhibitors is a valid strategy in cancer therapy. Since the approval of the first EGFR-TKI in 2003, a huge number of EGFR inhibitors were reported. Classification of these inhibitors could help the researchers to understand their structure-activity relationship. Herein, we introduce different types of classifications of the EGFR-TKIs, which received global approval for clinical use. In the following, the EGFR-targeting drugs are classified based on their chemistry, clinical use, target kinases, and the type of inhibition/interaction with EGFR. 
  • 3.7K
  • 25 Nov 2021
Topic Review
Nanocellulose
Nanocellulose can be used to improve the mechanical properties of cementitious materials if a proper dosage is used. Nanocellulose can be used as a type of viscosity-modifying agent (VMA) in cementitious materials. Nanocellulose with a proper dosage can reduce the shrinkage of cementitious materials, especially with a low water-to-cement (w/c) ratio. Four types of nanocelluloses, including cellulose nanocrystal, cellulose nanofibril, bacterial cellulose, and cellulose filament, have been used in cementitious materials.
  • 3.7K
  • 25 Dec 2020
Topic Review
Petroleum
Petroleum, also known as crude oil, or simply oil, is a naturally occurring yellowish-black liquid mixture of mainly hydrocarbons, and is found in geological formations. The name petroleum covers both naturally occurring unprocessed crude oil and petroleum products that consist of refined crude oil. A fossil fuel, petroleum is formed when large quantities of dead organisms, mostly zooplankton and algae, are buried underneath sedimentary rock and subjected to both prolonged heat and pressure. Petroleum has mostly been recovered by oil drilling. Drilling is carried out after studies of structural geology, sedimentary basin analysis, and reservoir characterisation. Recent developments in technologies have also led to exploitation of other unconventional reserves such as oil sands and oil shale. Once extracted, oil is refined and separated, most easily by distillation, into numerous products for direct use or use in manufacturing, such as gasoline (petrol), diesel and kerosene to asphalt and chemical reagents used to make plastics, pesticides and pharmaceuticals. Petroleum is used in manufacturing a wide variety of materials, and it is estimated that the world consumes about 100 million barrels (16 million cubic metres) each day. Petroleum production can be extremely profitable and was important for economic development in the 20th century, with some countries, so called "oil states", gaining significant economic and international power because of their control of oil production. Petroleum exploitation has significant negative environmental and social consequences. Most significantly, extraction, refining and burning of petroleum fuels all release large quantities of greenhouse gases, so petroleum is one of the major contributors to climate change. Furthermore, parts of the petroleum industry actively suppressed science and policy that aimed to prevent the climate crisis. Other negative environmental effects include the environmental impacts of exploration and exploitation of petroleum reserves, such as oil spills, and air and water pollution at the sites of utilization. All of these environmental impacts have direct health consequences for humans. Additionally, oil has also been a source of conflict leading to both state-led-wars and other kinds of conflicts (for example, oil revenue funded the Islamic State). Production of petroleum is expected to reach peak oil before 2035 as global economies lower dependencies on petroleum as part of climate change mitigation and a transition towards renewable energy and electrification. This is expected to have significant economic impacts that stakeholders argue need to be anticipated by a just transition and addressing the stranded assets of the petroleum industry.
  • 3.7K
  • 21 Oct 2022
Topic Review
Catalyst Design via Colloidal Synthesis
Supported nanoparticles are commonly applied in heterogeneous catalysis. The catalytic performance of these solid catalysts is, for a given support, dependent on the nanoparticle size, shape, and composition, thus necessitating synthesis techniques that allow for preparing these materials with fine control over those properties. Such control can be exploited to deconvolute their effects on the catalyst’s performance, which is the basis for knowledge-driven catalyst design. In this regard, bottom-up synthesis procedures based on colloidal chemistry have proven successful in achieving the desired level of control for a variety of fundamental studies. This article aims to give an overview of recent progress made in this synthesis technique for the application of controlled catalytic materials in gas-phase catalysis. The focus goes to mono- and bimetallic materials, as well as to recent efforts in enhancing their performance by embedding colloidal templates in porous oxide phases.
  • 3.6K
  • 12 May 2021
Topic Review
Overview of Polylactic Acid
Poly(lactic acid) (PLA) is an important polymer that is based on renewable biomass resources. Because of environmental issues, more renewable sources for polymers synthesis have been sought for industrial purposes.
  • 3.6K
  • 20 Jul 2022
Topic Review
Carbon Dots: Synthesis and Properties
Carbon dots (CDs) are zero-dimensional optically active carbon-based nanomaterials with a size of less than 10 nm. The material property of the CD is largely linked to the various bottom-up & top-down synthesis approaches, including surface passivation and functionalization, and the carbon precursors. The CDs can be engineered to enhance the chemical and physical functional properties by doping with heteroatom such as nitrogen, phosphorus, sulfur, fluorine, and boron. Because of its various advantageous properties, CDs are utilized in the field of chemical/biological sensing, bioimaging, and drug delivery. These nanosized CDs can change their light emission properties in response to various external stimuli such as pH, temperature, pressure, and light. The CD’s remarkable stimuli-responsive smart material properties have recently stimulated massive research interest for their exploitation to develop various sensor platforms. 
  • 3.6K
  • 16 Mar 2021
Topic Review
Nanodiamonds Synthesis Techniques
The "state-of-the-art" of the nanodiamonds synthesis techniques is reviewed with emphasis on the more recent one involving pulsed laser ablation. Production of NV centers inside the nanodiamonds and  post-production cleaning processes to remove residual graphite layers are also described.
  • 3.6K
  • 27 Oct 2020
Topic Review
Keto–Enol Tautomerism
In organic chemistry, keto–enol tautomerism refers to a chemical equilibrium between a keto form (a ketone or an aldehyde) and an enol (an alcohol). The keto and enol forms are said to be tautomers of each other. The interconversion of the two forms involves the movement of an alpha hydrogen atom and the reorganisation of bonding electrons; hence, the isomerism qualifies as tautomerism. A compound containing a carbonyl group (C=O) is normally in rapid equilibrium with an enol tautomer, which contains a pair of doubly bonded carbon atoms adjacent to a hydroxyl (−OH) group, C=C-OH. The keto form predominates at equilibrium for most ketones. Nonetheless, the enol form is important for some reactions. The deprotonated intermediate in the interconversion of the two forms, referred to as an enolate anion, is important in carbonyl chemistry, in large part because it is a strong nucleophile. Normally, the keto–enol tautomerization chemical equilibrium is highly thermodynamically driven, and at room temperature the equilibrium heavily favors the formation of the keto form. A classic example for favoring the keto form can be seen in the equilibrium between vinyl alcohol and acetaldehyde (K = [enol]/[keto] ≈ 3 × 10−7). However, it is reported that in the case of vinyl alcohol, formation of a stabilized enol form can be accomplished by controlling the water concentration in the system and utilizing the kinetic favorability of the deuterium-produced kinetic isotope effect (kH+/kD+ = 4.75, kH2O/kD2O = 12). Deuterium stabilization can be accomplished through hydrolysis of a ketene precursor in the presence of a slight stoichiometric excess of heavy water (D2O). Studies show that the tautomerization process is significantly inhibited at ambient temperatures ( kt ≈ 10−6 M/s), and the half-life of the enol form can easily be increased to t1/2 = 42 minutes for first-order hydrolysis kinetics. Another exception is the 1,3-diketones, such as acetylacetone (2,4-pentanedione), which favor the enol form.
  • 3.5K
  • 24 Oct 2022
Topic Review
Coumarin
Coumarin (2H-1-benzopyran-2-one) is an oxygen containing heterocycle and belongs to the subcategory of lactones.
  • 3.5K
  • 06 Jan 2021
Topic Review
Weave Structure and Fabric Properties
Fabric structures are created by interlacing yarns or intermeshing loops to create two-dimensional (2D) flexible materials. The most prevalent structure is woven fabrics, which are made up of two sets of perpendicular yarns that are crossed and interwoven to form a coherent and stable structure.
  • 3.5K
  • 16 Sep 2022
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