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Topic Review
Aromatic Hydrocarbon
An aromatic hydrocarbon or arene (or sometimes aryl hydrocarbon) is a hydrocarbon with sigma bonds and delocalized pi electrons between carbon atoms forming a circle. In contrast, aliphatic hydrocarbons lack this delocalization. The term "aromatic" was assigned before the physical mechanism determining aromaticity was discovered, and referred simply to the fact that many such compounds have a sweet or pleasant odour; however, not all aromatic compounds have a sweet odour, and not all compounds with a sweet odour are aromatic. The configuration of six carbon atoms in aromatic compounds is called a "benzene ring", after the simplest possible such hydrocarbon, benzene. Aromatic hydrocarbons can be monocyclic (MAH) or polycyclic (PAH). Not all aromatic compounds are benzene-based; aromaticity can also manifest in heteroarenes, which follow Hückel's rule (for monocyclic rings: when the number of its π electrons equals 4n + 2, where n = 0, 1, 2, 3, ...). In these compounds, at least one carbon atom is replaced by one of the heteroatoms oxygen, nitrogen, or sulfur. Examples of non-benzene compounds with aromatic properties are furan, a heterocyclic compound with a five-membered ring that includes a single oxygen atom, and pyridine, a heterocyclic compound with a six-membered ring containing one nitrogen atom.
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  • 25 Nov 2022
Topic Review
Compounds of Zinc
Compounds of zinc are chemical compounds containing the element zinc which is a member of the group 12 of the periodic table. The oxidation state of most compounds is the group oxidation state of +2. Zinc may be classified as a post-transition main group element with zinc(II). Zinc compounds are noteworthy for their nondescript behavior, they are generally colorless (unlike other elements with the oxidation number +2, which are usually white), do not readily engage in redox reactions, and generally adopt symmetrical structures.
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  • 25 Nov 2022
Topic Review
Robitussin
Cold medicines are a group of medications taken individually or in combination as a treatment for the symptoms of the common cold and similar conditions of the upper respiratory tract. The term encompasses a broad array of drugs, including analgesics, antihistamines and decongestants, among many others. It also includes drugs which are marketed as cough suppressants or antitussives, but their effectiveness in reducing cough symptoms is unclear or minimal. While they have been used by 10% of American children in any given week, they are not recommended in Canada or the United States in children six years or younger because of lack of evidence showing effect and concerns of harm. One version with codeine, guaifenesin, and pseudoephedrine was the 213th most commonly prescribed medication in 2017, in the United States, with more than two million prescriptions.
  • 535
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Topic Review
From Triboelectric Nanogenerator to Uninterrupted Power Supply System
Triboelectric nanogenerator (TENG) was invented in 2012 and is undergoing fast progress in tandem with the notion of switching to cleaner forms of energy, such as thermal, mechanical, biochemical, and solar, as well as any other forms of environmental energy. Based on the coupled effects of contact electrification and electrostatic induction, TENG represents a significant technological advance in converting various mechanical energies present in the ambient environment into electrical energy. Because of its benefits for environmental friendliness, low cost, sound efficiency, and a wide range of material alternatives, it has been extensively employed in several varieties of self-powered electronic gadgets, such as wireless sensors, implanted medical equipment, chemical sensors, electrochemical processes, household appliances, security detection systems, human-machine interfaces (HMIs), and artificial intelligence (AI).
  • 319
  • 25 Nov 2022
Topic Review
Skeletal Muscle Gene Delivery
Since Jon A. Wolff found skeletal muscle cells being able to express foreign genes and Russell J. Mumper increased the gene transfection efficiency into the myocytes by adding polymers, skeletal muscles have become a potential gene delivery and expression target. Different methods have been developing to deliver transgene into skeletal muscles. Among them, viral vectors may achieve potent gene delivery efficiency. Therefore, non-viral biomaterial-mediated methods with reliable biocompatibility are promising tools for intramuscular gene delivery in situ. A series of advanced non-viral gene delivery materials and related methods have been reported, such as polymers, liposomes, cell penetrating peptides, as well as physical delivery methods.
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  • 25 Nov 2022
Topic Review
Triboelectric Nanogenerators in Sustainable Chemical Sensors
The rapid development of sensing technology has created an urgent need for chemical sensor systems that can be rationally integrated into efficient, sustainable, and wearable electronic systems. In this case, the triboelectric nanogenerator (TENG) is expected to be a major impetus to such innovation because it can not only power the sensor by scavenging mechanical energies and transforming them into electricity but also act as the chemical sensor itself due to its intrinsic sensitivity towards the chemical reaction that occurs at the triboelectric interface.
  • 599
  • 24 Nov 2022
Topic Review
Self-Healable Lithium-Ion Batteries
The inner constituents of lithium-ion batteries (LIBs) are easy to deform during charging and discharging processes, and the accumulation of these deformations would result in physical fractures, poor safety performances, and short lifespan of LIBs. The introduction of self-healing (SH) materials into electrodes or electrolytes can bring about great enhancements in their mechanical strength, thus optimizing the cycle stability of the batteries. Due to the self-healing property of these special functional materials, the fractures/cracks generated during repeated cycles could be spontaneously cured. 
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  • 24 Nov 2022
Topic Review
Aqueous Zinc-Ion Batteries and Flexible Zinc-Ion Batteries
Lithium-ion batteries (LIBs) have been considered an easily accessible battery technology because of their low weight, cheapness, etc. Unfortunately, they have significant drawbacks, such as flammability and scarcity of lithium. Since the components of zinc-ion batteries are nonflammable, nontoxic, and cheap, aqueous zinc-Ion batteries (AZIBs) could be a suitable replacement for LIBs. 
  • 656
  • 24 Nov 2022
Topic Review
Westinghouse Lamp Plant
Coordinates: 40°46′53″N 74°11′45″W / 40.78137°N 74.19592°W / 40.78137; -74.19592 The Westinghouse Lamp Plant located in Bloomfield, New Jersey, was one of the lamp manufacturing plants of Westinghouse Electric Corporation. The plant had a major involvement in supplying uranium metal for the world's first self-sustaining chain reaction in Chicago (Chicago Pile-1) in the early phase of the Manhattan Project to create the first atomic bomb.
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Topic Review
Alchemy and Chemistry in Medieval Islam
Alchemy and chemistry in Islam refers to the study of both traditional alchemy and early practical chemistry (the early chemical investigation of nature in general) by scholars in the medieval Islamic world. The word alchemy was derived from the Arabic word كيمياء or kīmiyāʾ. and may ultimately derive from the ancient Egyptian word kemi, meaning black. After the fall of the Western Roman Empire, the focus of alchemical development moved to the Caliphate and the Islamic civilization. Much more is known about Islamic alchemy as it was better documented; most of the earlier writings that have come down through the years were preserved as Arabic translations.
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