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Topic Review
Neutralization
In chemistry, neutralization or neutralisation (see spelling differences) is a chemical reaction in which acid and a base react quantitatively with each other. In a reaction in water, neutralization results in there being no excess of hydrogen or hydroxide ions present in the solution. The pH of the neutralized solution depends on the acid strength of the reactants.
  • 3.5K
  • 22 Nov 2022
Topic Review
Glycerol
Glycerol (1,2,3-propanetriol) is a viscous odorless and colorless liquid, with a syrupy sweet flavor that may derive from both renewable and fossil sources
  • 3.5K
  • 06 Jan 2021
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.
  • 3.5K
  • 04 Nov 2022
Topic Review
Biofilm and Pathogen Inhibition in Cooling Towers Using Natural Chemistry
Industrial comfort cooling and process cooling typically employ water evaporative cooling towers (CTs) to dissipate reject heat.  This warm water, enriched with nutrient materials scrubbed from the air or in source water, provides a nurturing environment for a wide variety of neutrophilic microorganisms, some of which are human pathogens.  For example, cases of Legionella pneumophila infection have been traced to CT Systems that have become pubic hazards in recent years.  Typically, one or more toxic microbicides are applied to control the problem.  This article highlights two case studies that utilize ultra-softened (<0.3 mg/L total hardness), highly-concentrated chemical components, naturally present in almost all makeup water sources used by CT Systems, that can generate high-pH, high-TDS cooling water.  At sufficient concentrations, these two natural parameters are hostile to microorganisms, including protozoa and slime-forming (biofilm) bacteria that harbor pathogens.  Field testing for Adenosine Tri-Phosphate (ATP), reported in Relative Light Units (RLU), provides a quick, sensitive method to detect all water-borne microbiological activity present in CT Systems and verifies the effectiveness of the anti-microbial program by quantifiable data, reported as ATP-RLU.
  • 3.5K
  • 28 Oct 2020
Topic Review
Duckweed
Duckweed is the smallest and fastest-growing aquatic plant, and has advantages including simple processing and the ability to grow high biomass in smaller areas.
  • 3.5K
  • 20 Feb 2021
Topic Review
Muscle
Muscle is a soft tissue found in most animals, and is one of the four basic animal tissues, along with nervous tissue, epithelium, and connective tissue. Muscle cells contain protein filaments called myofilaments of actin and myosin that slide past one another, producing a contraction that changes both the length and the shape of the cell. Muscles function to produce force and motion. They are primarily responsible for maintaining and changing posture, locomotion, as well as movement of internal organs, such as the contraction of the heart and the movement of food through the digestive system via peristalsis. Muscle tissue is derived from the embryonic mesodermal germ layer in a process known as myogenesis. There are three types of muscle, of which skeletal and cardiac muscle are striated and smooth muscle is not. Muscle action can be classified as being either voluntary or involuntary. Cardiac and smooth muscles contract without conscious thought and are termed involuntary, whereas the skeletal muscles contract upon command. Skeletal muscles in turn can be divided into fast and slow twitch fibers. Muscles are predominantly powered by the oxidation of fats and carbohydrates, but anaerobic chemical reactions are also used, particularly by fast twitch fibers. These chemical reactions produce adenosine triphosphate (ATP) molecules that are used to power the movement of the myosin heads. The term muscle is derived from the Latin musculus meaning "little mouse" perhaps because of the shape of certain skeletal muscles or because contracting muscles look like mice moving under the skin.
  • 3.5K
  • 22 Oct 2022
Topic Review
Polycom
Polycom, now a part of Plantronics, was an American multinational corporation that develops video, voice and content collaboration and communication technology. Polycom was co-founded in 1990 by Brian L Hinman and Jeffrey Rodman. In 2018 Polycom was acquired by Plantronics and in 2019 the name of the combined entity was changed to Poly. On March 28, 2022 HP Inc. announced it would be acquiring Poly (company) in a deal totaling $1.7 billion USD.
  • 3.5K
  • 09 Nov 2022
Topic Review
Solvent-Free Synthesis of Zeolites
The traditional hydrothermal method to prepare zeolite will inevitably use a large amount of water as a solvent, which will lead to higher autogenous pressure, low efficiency, and wastewater pollution. The solvent-free method can be used to synthesize various types of zeolites by mechanical mixing, grinding, and heating of solid raw materials, which exhibits the apparent advantages of high yield, low pollution, and high efficiency. This review mainly introduces the development process of solvent-free synthesis, preparation of hierarchical zeolite, morphology control, synthesis mechanism and applications of solvent-free methods. It can be believed that solvent-free methods will become a research focus and have enormous industrial application potential.
  • 3.5K
  • 25 Mar 2021
Topic Review
Astronomy
Astronomy (from grc ἀστρονομία (Script error: No such module "Ancient Greek".) 'science that studies the laws of the stars') is a natural science that studies celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and evolution. Objects of interest include planets, moons, stars, nebulae, galaxies, and comets. Relevant phenomena include supernova explosions, gamma ray bursts, quasars, blazars, pulsars, and cosmic microwave background radiation. More generally, astronomy studies everything that originates beyond Earth's atmosphere. Cosmology is a branch of astronomy that studies the universe as a whole. Astronomy is one of the oldest natural sciences. The early civilizations in recorded history made methodical observations of the night sky. These include the Babylonians, Greeks, Indians, Egyptians, Chinese, Maya, and many ancient indigenous peoples of the Americas. In the past, astronomy included disciplines as diverse as astrometry, celestial navigation, observational astronomy, and the making of calendars. Nowadays, professional astronomy is often said to be the same as astrophysics. Professional astronomy is split into observational and theoretical branches. Observational astronomy is focused on acquiring data from observations of astronomical objects. This data is then analyzed using basic principles of physics. Theoretical astronomy is oriented toward the development of computer or analytical models to describe astronomical objects and phenomena. These two fields complement each other. Theoretical astronomy seeks to explain observational results and observations are used to confirm theoretical results. Astronomy is one of the few sciences in which amateurs play an active role. This is especially true for the discovery and observation of transient events. Amateur astronomers have helped with many important discoveries, such as finding new comets.
  • 3.5K
  • 05 Dec 2022
Topic Review Peer Reviewed
COVID-19 in the Construction Sector
This section analyzes the influence of COVID-19 in the construction sector. Construction workers’ high vulnerability to the spread of the virus motivated this entry. The construction sector’s peculiarities and some work procedure characteristics in this sector make telecommuting impossible in most activities. In addition, most of the states and national governments declared the construction sector essential activity due to its high economic impact. The working conditions in this sector are very special: constant trips to work in groups, work group execution with little interpersonal distance, group travel, stays and accommodations away from home, meals in restaurants or work canteens, lunch in restaurants or work canteens, etc. Due to all of this, the contagion rate was very high during the pandemic months. Even today, it is still considered one of the most dangerous sectors for these purposes. With all this in mind, here we discuss why it is difficult to minimize the spread of the virus for construction workers, summarize how to assess exposure risk grades for construction job tasks, and provide possible protection requirements for the different exposure risk grades. 
  • 3.5K
  • 14 Apr 2022
Topic Review
Failure Modes of the Electric Motors
The reliability assessment of electric machines plays a very critical role in today’s engineering world. The reliability assessment requires a good understanding of electric motors and their root causes. Electric machines mostly fail due to mechanical problems and bearing damage is the main source of this. The bearings can be damaged by mechanical, electrical, and thermal stresses. Among all stresses, the researcher should give special attention to the electrical one, which is bearing current and shaft voltage.
  • 3.5K
  • 21 Jun 2023
Topic Review
Addiction Psychology
Professionals view addiction as a disease or a choice. One model is referred to as the disease model of addiction. The second model is the choice model of addiction. Researchers argue that the addiction process is like the disease model with a target organ being the brain, some type of defect, and symptoms of the disease. Addiction is like the choice model with a disorder of genes, a reward, memory, stress, and choice. Both models result in compulsive behavior. Substance addictions relate to drugs, alcohol, and smoking. Process addictions relate to non-substance-related behaviors such as gambling, spending, sexual activity, gaming, the internet, and food. Psychologists' oldest definition of addiction is that the addict has a lack of self-control from something that has an awarding effect that keeps you coming back . The addicted party wants to abstain, but they can't resist the temptation. Addicts lose control over their actions. It is viewed that an addict battles with their addiction and wanting abstinence and gain control over their actions.
  • 3.5K
  • 03 Nov 2022
Topic Review
Opuntia ficus-indica (L.) Mill Species
Opuntia ficus-indica (L.) Mill. (OFI) belongs to the Cactaceae family, which contains about 130 genera and nearly 1600 species. This plant is originally from South America, namely Mexico, and can be found in the Middle East, South Africa, India, Australia, and some Mediterranean countries.
  • 3.5K
  • 26 Apr 2023
Topic Review
Cinnamon (Desktop Environment)
Cinnamon is a free and open-source desktop environment for the X Window System that derives from GNOME 3 but follows traditional desktop metaphor conventions. Cinnamon is the principal desktop environment of the Linux Mint distribution and is available as an optional desktop for other Linux distributions and other Unix-like operating systems as well. The development of Cinnamon began as a reaction to the April 2011 release of GNOME 3 in which the conventional desktop metaphor of GNOME 2 was abandoned in favor of GNOME Shell. Following several attempts to extend GNOME 3 such that it would suit the Linux Mint design goals, the Mint developers forked several GNOME 3 components to build an independent desktop environment. Separation from GNOME was completed in Cinnamon 2.0, which was released in October 2013. Applets and desklets are no longer compatible with GNOME 3. As the distinguishing factor of Linux Mint, Cinnamon has generally received favorable coverage by the press, in particular for its ease-of-use and gentle learning curve. With respect to its conservative design model, Cinnamon is similar to the Xfce and GNOME 2 (MATE and GNOME Flashback/Classic) desktop environments.
  • 3.5K
  • 07 Nov 2022
Biography
Hermann Oberth
Hermann Julius Oberth (German: [ˈhɛrman ˈjuːli̯ʊs ˈoːbɛrt]; 25 June 1894 – 28 December 1989) was an Austro-Hungarian-born German physicist and engineer. He is considered one of the founding fathers of rocketry and astronautics, along with the French Robert Esnault-Pelterie, the Russian Konstantin Tsiolkovsky, and the American Robert Goddard.[1][2] Hermann Oberth as a young boy,
  • 3.5K
  • 05 Dec 2022
Topic Review
Beer Brewed from Sorghum
Beer is a complex beverage system despite being made up of only four ingredients: yeast, water, hops, and malted grain. Typically, malted barley is used as the primary grain source for brewing, however alternative grains/pseudo-grains like sorghum are gaining popularity. However, the use of sorghum in beer manufacturing does have its issues, which are largely due to its low amylolytic activity (which is insufficient for complete saccharification), high gelatinization temperature, and low free amino content. Sorghum malt has a higher concentration of alpha-amylase and a lower concentration of beta-amylase compared to malted barley. Due to the reduced enzymatic activity of sorghum this deficiency can lead to insufficient production of fermentable sugars, high dextrin content, and increased viscosity. Due to sorghum’s higher gelatinization temperature, the hydrolysis of sugars into fermentable sugars is only partially completed. Thus, resulting in fewer fermentable sugars for the yeast to metabolize for the production of ethanol, and volatile and semi-volatile compounds.
  • 3.5K
  • 17 Aug 2021
Topic Review
Fashion Recommendation Systems
Image-based fashion recommendation systems (FRSs) have attracted a huge amount of attention from fast fashion retailers as they provide a personalized shopping experience to consumers. With the technological advancements, this branch of artificial intelligence exhibits a tremendous amount of potential in image processing, parsing, classification, and segmentation.
  • 3.5K
  • 12 Aug 2021
Topic Review
Thallium
Thallium, as a pharmaceutical cosmetic product, is applied for facial hair removal and fungal infections of the scalp. Thallium acetate is currently used as a catalyst in organic synthesis in the oxidation of olefins and hydrocarbons, and in epoxidation and polymerization reactions. Detection of Tl is a challenging task because its concentration in environmental samples may be at a nanogram per gram level or lower.
  • 3.5K
  • 23 Nov 2021
Topic Review
List of Minerals H (Complete)
This list includes those recognised minerals beginning with the letter H. The International Mineralogical Association is the international group that recognises new minerals and new mineral names, however minerals discovered before 1959 did not go through the official naming procedure, although some minerals published previously have been either confirmed or discredited since that date. This list contains a mixture of mineral names that have been approved since 1959 and those mineral names believed to still refer to valid mineral species (these are called "grandfathered" species). The data was exported from mindat.org on 29 April 2005; updated up to 'IMA2018'. The minerals are sorted by name, followed by the structural group (rruff.info/ima and ima-cnmnc by mineralienatlas.de, mainly) or chemical class (mindat.org and basics), the year of publication (if it's before of an IMA approval procedure), the IMA approval and the Nickel–Strunz code. The first link is to mindat.org, the second link is to webmineral.com, and the third is to the Handbook of Mineralogy (Mineralogical Society of America).
  • 3.5K
  • 27 Nov 2022
Topic Review
Animal Jam
Animal Jam is an online virtual world developed by WildWorks. It was originally launched in 2010, in collaboration with the National Geographic Society. With about 160 million registered players, Animal Jam is one of the many fastest-growing online children's properties in the world. In Animal Jam, players discover and learn various facts about zoology using the game's numerous features, including mini-games, adventures, parties, and social interactions. Due to its growing popularity, Animal Jam has spawned different types of merchandise, including figurine toys, children's books, and a subscription box. Although Animal Jam is primarily played online, the Animal Jam universe has been expanded to incorporate mobile devices such as smartphones, tablets, and iOS devices. The most popular Animal Jam mobile app is Play Wild which is a 3D version of the Animal Jam world. WildWorks has also developed other apps that are based on the Animal Jam game including Tunnel Town, AJ Jump, and Dash Tag.
  • 3.5K
  • 24 Nov 2022
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