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Topic Review
Types of Electrochemical Energy Storage Devices
Researchers are increasingly paying attention to sustainable methods for storing energy. Many researchers are now concentrating their efforts on the development and exploration of novel materials for use in energy storage devices due to the limited supply of existing energy sources such as oil, coal, and natural gas, and escalating regional tensions. Because of these issues, sustainable renewable energy sources have been touted as an alternative to nonrenewable fuels. Deployment of renewable energy sources requires efficient and reliable energy storage devices due to their intermittent nature. High-performance electrochemical energy storage technologies with high power and energy densities are heralded to be the next-generation storage devices. Transition metal chalcogenides (TMCs) have sparked interest among electrode materials because of their intriguing electrochemical properties.
  • 3.1K
  • 09 Jun 2022
Topic Review
Cotton Production in Pakistan
Cotton production in Pakistan is integral to the economic development of the country. The nation is largely dependent on the cotton industry and its related textile sector, and the crop has been given a principal status in the country. Cotton is grown as an industrial crop in 15% of the nation's land during the monsoon months of May to August, known as the kharif period, and is grown at a smaller scale between February and April. Record production of cotton was reported at 15 million bales of 470 pounds (210 kg) each in the form of phutti (seed cotton) during 2014–15, which was an 11% rise compared to the previous season (2013–14). Production-wise, as of 2012–13, Pakistan occupied the fourth position among the cotton growers of the world, the first three being China, India and the United States, in that order. In respect of exports of raw cotton, Pakistan holds third position, and is the fourth in consumption (about 30 and 40 per cent of its production). It is the largest exporter of cotton yarn.
  • 3.1K
  • 16 Nov 2022
Topic Review
Atropa Belladonna
Atropa belladonna, commonly known as belladonna or deadly nightshade, is a toxic perennial herbaceous plant in the nightshade family Solanaceae, which also includes tomatoes, potatoes, and eggplant (aubergine). It is native to Europe, North Africa, and Western Asia. Its distribution extends from Great Britain in the west to western Ukraine and the Iranian province of Gilan in the east. It is also naturalised or introduced in some parts of Canada and the United States. The foliage and berries are extremely toxic when ingested, containing tropane alkaloids. These toxins include atropine, scopolamine, and hyoscyamine, which cause delirium and hallucinations, and are also used as pharmaceutical anticholinergics. Tropane alkaloids are of common occurrence not only in the Old World tribes Hyoscyameae (to which the genus Atropa belongs) and Mandragoreae, but also in the New World tribe Datureae - all of which belong to the subfamily Solanoideae of the plant family Solanaceae. Atropa belladonna has unpredictable effects. The antidote for belladonna poisoning is physostigmine or pilocarpine, the same as for atropine.
  • 3.1K
  • 25 Nov 2022
Topic Review
Chinese Alchemy
Chinese alchemy is an ancient Chinese scientific and technological approach to alchemy, a part of the larger tradition of Taoist body-spirit cultivation developed from the traditional Chinese understanding of medicine and the body. According to original texts such as the Cantong qi, the body is understood as the focus of cosmological processes summarized in the five agents, or wu xing, the observation and cultivation of which leads the practitioner into greater alignment with the operation of the Tao, the great cosmological principle of everything. Therefore, the traditional view in China is that alchemy focuses mainly on the purification of one's spirit and body in the hopes of gaining immortality through the practice of Qigong and/or consumption and use of various concoctions known as alchemical medicines or elixirs, each of which having different purposes. Pao zhi (Pao chi) cites the pharmacological processing (of Chinese materia medica) as used in the practice of Traditional Chinese Medicine, such as honey or wine frying and roasting with toxic metals such as mercury, lead, and arsenic. According to J.C. Cooper's Chinese Alchemy: The Taoist Quest for Immortality, Taoism had two distinct parts, the classical Tao Chia, which was mystical and stemmed primarily from Laozi and Zhuangzi, and the more popular Tao Chiao, which was the popular, magical and alchemical side of Taoism. Cooper states that a common viewpoint is that "classical Taoism [Daoism] was the original but was too austere and rarefied for the general populace ... [but] Tao Chiao fulfilled the day-to-day needs of the people."
  • 3.0K
  • 16 Nov 2022
Topic Review
Xeno Nucleic Acid
Xeno nucleic acid (XNA) is a synthetic alternative to the natural nucleic acids DNA and RNA as information-storing biopolymers that differs in the sugar backbone. As of 2011, at least six types of synthetic sugars have been shown to form nucleic acid backbones that can store and retrieve genetic information. Research is now being done to create synthetic polymerases to transform XNA. The study of its production and application has created a field known as xenobiology. Although the genetic information is still stored in the four canonical base pairs (unlike other nucleic acid analogues), natural DNA polymerases cannot read and duplicate this information. Thus the genetic information stored in XNA is "invisible" and therefore useless to natural DNA-based organisms.
  • 3.0K
  • 01 Nov 2022
Topic Review
Shape-Memory Polymers in Dentistry
Objective: To perform a systematic review (SR) of existing literature and a patent landscape report (PLR) regarding the potential applications of shape-memory polymers (SMPs) in dentistry. Search strategy: Clinical and Biomedical online databases (Pubmed, Medline via Embase, Scopus, LILACS, Web of Science, Cochrane Library), Materials Science and Engineering databases (IEEE Explore, Compendex, Proquest), Material Science and Chemical database (Reaxys) so as Patents databases (Questel-Orbit, Espacenet, Patentscope) were consulted as recently as January 2019 to identify all papers and patents potentially relevant to the review. The reference lists of all eligible studies were hand searched for additional published work. Results: After duplicate selection and extraction procedures, 6 relevant full-text articles from the initial 302 and 45 relevant patents from 497 were selected. A modified Consolidated Standards of Reporting Trials (CONSORT) checklist of 14 items for reporting pre-clinical in-vitro studies was used to rate the methodological quality of the selected papers. The overall quality was judged low. Conclusions: Despite the great potential and versatility of SMPs, it was not possible to draw evidence-based conclusions supporting their immediate employment in clinical dentistry. This was due to the weak design and a limited number of studies included within this review and reflects the fact that additional research is mandatory to determine whether or not the use of SMPs in dentistry could be effective. Nevertheless, the qualitative analysis of selected papers and patents indicate that SMPs are promising materials in dentistry because of their programmable physical properties. These findings suggest the importance of furtherly pursuing this line of research.
  • 3.0K
  • 28 Oct 2020
Topic Review
Austenite Stability
The austenite stability represents the potential of metastable austenite grains in resisting the martensitic phase transformation under an applied either thermal or mechanical driving force. 
  • 3.0K
  • 18 Aug 2020
Topic Review
Ballast Contamination Mechanisms
Ballasted railway tracks constitute the major transportation grids in many countries across the globe; they convey commuters, as well as freight and bulk cargoes, between cities, mines, farmlands, and ports . The railtrack structure can be categorised into two groups: the substructure and the superstructure. The substructure comprises the subgrade, the sub-ballast, and the ballast, while the superstructure encompasses the sleepers (timber or concrete), the fastening mechanism, and the steel rails.
  • 3.0K
  • 14 Jan 2021
Topic Review
Green Tea
Green tea is a type of tea that is made from Camellia sinensis leaves that have not undergone the same withering and oxidation process used to make oolong teas and black teas. Green tea originated in China , but its production and manufacture has spread to many other countries in Asia. Several varieties of green tea exist, which differ substantially based on the variety of C. sinensis used, growing conditions, horticultural methods, production processing, and time of harvest. Although there has been considerable research on the possible health effects of consuming green tea regularly, there is little evidence that drinking green tea has any effects on health.
  • 3.0K
  • 08 Nov 2022
Topic Review
Biological Functions of Nitric Oxide
Nitric oxide (nitrogen monoxide) is a molecule and chemical compound with chemical formula of NO. In mammals including humans, nitric oxide is a signaling molecule involved in several physiological and pathological processes. It is a powerful vasodilator with a half-life of a few seconds in the blood. Standard pharmaceuticals such as nitroglycerine and amyl nitrite are precursors to nitric oxide. Low levels of nitric oxide production are typically due to ischemic damage in the liver. As a consequence of its importance in neuroscience, physiology, and immunology, nitric oxide was proclaimed "Molecule of the Year" in 1992. Research into its function led to the 1998 Nobel Prize for elucidating the role of nitric oxide as a cardiovascular signalling molecule.
  • 2.9K
  • 04 Nov 2022
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.
  • 2.9K
  • 24 Nov 2022
Topic Review
Hydrogen Evolution Reaction
In recent years, heteroatom doping has been found to be an effective strategy to improve the electrocatalytic hydrogen evolution reaction (HER) performances of nickel-based catalysts in acidic, neutral, and alkaline media. 
  • 2.9K
  • 26 Oct 2020
Topic Review
Backbone Chain
In polymer science, the backbone chain of a polymer is the longest series of covalently bonded atoms that together create the continuous chain of the molecule. This science is subdivided into the study of organic polymers, which consist of a carbon backbone, and inorganic polymers which have backbones containing only main group elements. In biochemistry, organic backbone chains make up the primary structure of macromolecules. The backbones of these biological macromolecules consist of central chains of covalently bonded atoms. The characteristics and order of the monomer residues in the backbone make a map for the complex structure of biological polymers (see Biomolecular structure). The backbone is, therefore, directly related to biological molecules’ function. The macromolecules within the body can be divided into four main subcategories, each of which are involved in very different and important biological processes: proteins, carbohydrates, lipids, and nucleic acids. Each of these molecules has a different backbone and consists of different monomers each with distinctive residues and functionalities. This is the driving factor of their different structures and functions in the body. Although lipids have a "backbone," they are not true biological polymers as their backbone is a three carbon molecule, glycerol, with longer substituent "side chains." For this reason, only proteins, carbohydrates, and nucleic acids should be considered as biological macromolecules with polymeric backbones.
  • 2.7K
  • 21 Nov 2022
Topic Review
Relaxor Ferroelectrics for Energy Storage
Ferroelectrics (FE) are polar materials with spontaneous polarization that can be reoriented by changing the direction of the external applied electric field.
  • 2.5K
  • 08 Feb 2021
Topic Review
Comparison of Chernobyl and Other Radioactivity Releases
This article compares the radioactivity release and decay from the Chernobyl disaster with various other events which involved a release of uncontrolled radioactivity.
  • 2.5K
  • 07 Oct 2022
Topic Review
Additively Manufactured Aluminium Alloys
Metal additive manufacturing (MAM), also known as metal 3D printing, is a rapidly growing industry based on the fabrication of complex metal parts with improved functionalities. During MAM, metal parts are produced in a layer by layer fashion using 3D computer–aided design models. The advantages of using this technology includes the reduction of materials waste, high efficiency for small production runs, near net shape manufacturing, ease of change or revision of versions of a product, support of lattice structures, and rapid prototyping. Numerous metals and alloys can nowadays be processed by additive manufacturing techniques. Among them, Al-based alloys are of great interest for the automotive and aeronautic industry due to their relatively high strength and stiffness to weight ratio, good wear and corrosion resistance, and recycling potential. The special conditions associated with the MAM processes are known to produce in these materials a very fine microstructure with unique directional growth features far from equilibrium. This distinctive microstructure, together with other special features and microstructural defects originating from the additive manufacturing process are known to greatly influence the corrosion behavior of these materials. Several works have already been conducted in this direction. However, a number of issues concerning the corrosion and corrosion protection of these materials are still not well understood. This work reviews the main studies to date investigating the corrosion aspects of additively manufactured aluminium alloys. It also provides a summary and outlook of relevant directions to be explored in future research.
  • 2.4K
  • 13 Jan 2021
Topic Review
N-Butanol
n-Butanol or n-butyl alcohol or normal butanol is a primary alcohol with a 4-carbon structure and the chemical formula C4H9OH. Its isomers include isobutanol, 2-butanol, and tert-butanol. Butanol is one of the group of "fusel alcohols" (from the German for "bad liquor"), which have more than two carbon atoms and have significant solubility in water. n-Butanol occurs naturally as a minor product of the fermentation of sugars and other carbohydrates, and is present in many foods and beverages. It is also a permitted artificial flavorant in the United States, used in butter, cream, fruit, rum, whiskey, ice cream and ices, candy, baked goods and cordials. It is also used in a wide range of consumer products. The largest use of n-butanol is as an industrial intermediate, particularly for the manufacture of butyl acetate (itself an artificial flavorant and industrial solvent). It is a petrochemical, manufactured from propylene and usually used close to the point of manufacture. Estimated production figures for 1997 are: United States 784,000 tonnes; Western Europe 575,000 tonnes; Japan 225,000 tonnes.
  • 2.4K
  • 26 Oct 2022
Topic Review
Coomassie Brilliant Blue
Coomassie Brilliant Blue is the name of two similar triphenylmethane dyes that were developed for use in the textile industry but are now commonly used for staining proteins in analytical biochemistry. Coomassie Brilliant Blue G-250 differs from Coomassie Brilliant Blue R-250 by the addition of two methyl groups. The name "Coomassie" is a registered trademark of Imperial Chemical Industries.
  • 2.4K
  • 08 Nov 2022
Topic Review
Flavor
A food flavoring or food flavouring, [lower-alpha 1] in short flavoring or flavouring, or alternatively aroma is a food additive used to improve the taste or smell of food. It changes the perceptual impression of food as determined primarily by the chemical senses of the gustatory and olfactory system. The trigeminal nerves, which detect chemical irritants in the mouth and throat, as well as temperature and texture, are also important to the overall perception of food. Of the three chemical senses, smell is the main determinant of a food item's flavor. Aromas are the volatile components of the food. The aroma of a food is determined by the aroma compounds it contains and the personal ability to detect them. While an aroma primarily acts through te olfactory system, it also affects the taste at the same time. Along with additives, other components like sugars determine the taste of food. Five basic tastes – sweet, sour, bitter, salty and umami (savory) are universally recognized, although some cultures also include pungency and oleogustus ("fattiness"). The number of food smells is unbounded; a food's flavor, therefore, can be easily altered by changing its smell while keeping its taste similar. This is exemplified in artificially flavored jellies, soft drinks and candies, which, while made of bases with a similar taste, have dramatically different flavors due to the use of different scents or fragrances. The flavorings of commercially produced food products are typically created by flavorists. A flavoring is defined as a substance that gives another substance taste, altering the characteristics of the solute, causing it to become sweet, sour, tangy, etc. Although the term, in common language, denotes the combined chemical sensations of taste and smell, the same term is used in the fragrance and flavors industry to refer to edible chemicals and extracts that alter the flavor of food and food products through the sense of smell. Owing to the high cost, or unavailability of natural flavor extracts, most commercial flavorants are "nature-identical", which means that they are the chemical equivalent of natural flavors, but chemically synthesized rather than being extracted from source materials. Identification of components of natural foods, for example a raspberry, may be done using technology such as headspace techniques, so the flavorist can imitate the flavor by using a few of the same chemicals present. In the EU legislation, the term "natural-identical flavouring" does not exist. The legislation is specified on what is a "flavouring" and a "natural flavouring". A flavor is a quality of something that affects the sense of taste.
  • 2.3K
  • 04 Nov 2022
Topic Review
Chlamydomonas Reinhardtii
Chlamydomonas reinhardtii is a single-cell green alga about 10 micrometres in diameter that swims with two flagella. It has a cell wall made of hydroxyproline-rich glycoproteins, a large cup-shaped chloroplast, a large pyrenoid, and an eyespot that senses light. Chlamydomonas species are widely distributed worldwide in soil and fresh water. Chlamydomonas reinhardtii is an especially well studied biological model organism, partly due to its ease of culturing and the ability to manipulate its genetics. When illuminated, C. reinhardtii can grow photoautotrophically, but it can also grow in the dark if supplied with organic carbon. Commercially, C. reinhardtii is of interest for producing biopharmaceuticals and biofuel, as well being a valuable research tool in making hydrogen.
  • 2.3K
  • 02 Nov 2022
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