|
Philosopher's Wool
Zinc oxide is an inorganic compound with the formula . It is a white powder which is insoluble in water. ZnO is used as an additive in numerous materials and products including cosmetics, food supplements, rubbers, plastics, ceramics, glass, cement, lubricants, paints, sunscreens, ointments, adhesives, sealants, pigments, foods, batteries, ferrites, fire retardants, semi conductors, and first-aid tapes. Although it occurs naturally as the mineral zincite, most zinc oxide is produced synthetically. History Early humans probably used zinc compounds in processed and unprocessed forms, as paint or medicinal ointment; however, their composition is uncertain. The use of ''pushpanjan'', probably zinc oxide, as a salve for eyes and open wounds is mentioned in the Indian medical text the Charaka Samhita, thought to date from 500 BC or before. Zinc oxide ointment is also mentioned by the Greek physician Dioscorides (1st century AD). Galen suggested treating ulcerating cancers with zinc ox ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zinc
Zinc is a chemical element; it has symbol Zn and atomic number 30. It is a slightly brittle metal at room temperature and has a shiny-greyish appearance when oxidation is removed. It is the first element in group 12 (IIB) of the periodic table. In some respects, zinc is chemically similar to magnesium: both elements exhibit only one normal oxidation state (+2), and the Zn2+ and Mg2+ ions are of similar size. Zinc is the 24th most abundant element in Earth's crust and has five stable isotopes. The most common zinc ore is sphalerite (zinc blende), a zinc sulfide mineral. The largest workable lodes are in Australia, Asia, and the United States. Zinc is refined by froth flotation of the ore, roasting, and final extraction using electricity ( electrowinning). Zinc is an essential trace element for humans, animals, plants and for microorganisms and is necessary for prenatal and postnatal development. It is the second most abundant trace metal in humans after iron, an import ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Avicenna
Ibn Sina ( – 22 June 1037), commonly known in the West as Avicenna ( ), was a preeminent philosopher and physician of the Muslim world, flourishing during the Islamic Golden Age, serving in the courts of various Iranian peoples, Iranian rulers. He is often described as the father of early modern medicine. His philosophy was of the Peripatetic school derived from Aristotelianism. His most famous works are ''The Book of Healing'', a philosophical and scientific encyclopedia, and ''The Canon of Medicine'', a medical encyclopedia which became a standard medical text at many medieval European University, universities and remained in use as late as 1650. Besides philosophy and medicine, Avicenna's corpus includes writings on Astronomy in medieval Islam, astronomy, Alchemy and chemistry in medieval Islam, alchemy, Geography and cartography in medieval Islam, geography and geology, Psychology in medieval Islam, psychology, Islamic theology, Logic in Islamic philosophy, logic, Mat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lead White
Lead white is a thick, opaque, and heavy white pigment composed primarily of basic lead carbonate, , with a crystalline molecular structure. It was the most widely produced and used white pigment in different parts of the world from antiquity until the nineteenth century, when it was displaced by zinc white and later by titanium white. Lead white has maintained relatively consistent production methods across times and regions, yet it has a wide range of applications in different contexts, such as home decoration, art production, and cosmetics. Given its affordability and distinctive visual qualities, lead white was particularly favored and generously used by artists in their paintings. However, most art supply companies now explicitly advise against the use of lead white because of the risk that it poses of lead poisoning. Even after this drawback was known, it continued to be used in paintings and cosmetics. Production methods As one of the oldest synthetically produced pigmen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Louis-Bernard Guyton De Morveau
Louis-Bernard Guyton, Baron de Morveau (also Louis-Bernard Guyton-Morveau after the French Revolution; 4 January 1737 – 2 January 1816) was a French chemist, politician, and aeronaut. He is credited with producing the first systematic method of chemical nomenclature. Early career Guyton de Morveau was born in Dijon, where he served as a lawyer, then '' avocat général'', of the Dijon ''parlement''. In 1773, already interested in chemistry, he proposed use of "muriatic acid gas" for fumigation of buildings and as a result is sometimes given credit for having suggested chlorine in this use. However, chlorine was not well characterized at that time, and hydrogen chloride (made by reacting sodium chloride and sulfuric acid) was actually the active gaseous fumigation agent. He was criticized by Jean Pierre Chardenon who told him that he should rest in his literary achievements and stay way from chemistry. This challenge led to his resigning his post in 1782 to dedicate himself ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bristol
Bristol () is a City status in the United Kingdom, cathedral city, unitary authority area and ceremonial county in South West England, the most populous city in the region. Built around the River Avon, Bristol, River Avon, it is bordered by the ceremonial counties of Gloucestershire to the north and Somerset to the south. The county is in the West of England combined authority area, which includes the Greater Bristol area (List of urban areas in the United Kingdom, eleventh most populous urban area in the United Kingdom) and nearby places such as Bath, Somerset, Bath. Bristol is the second largest city in Southern England, after the capital London. Iron Age hillforts and Roman villas were built near the confluence of the rivers River Frome, Bristol, Frome and Avon. Bristol received a royal charter in 1155 and was historic counties of England, historically divided between Gloucestershire and Somerset until 1373 when it became a county corporate. From the 13th to the 18th centur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
India
India, officially the Republic of India, is a country in South Asia. It is the List of countries and dependencies by area, seventh-largest country by area; the List of countries by population (United Nations), most populous country since 2023; and, since its independence in 1947, the world's most populous democracy. Bounded by the Indian Ocean on the south, the Arabian Sea on the southwest, and the Bay of Bengal on the southeast, it shares land borders with Pakistan to the west; China, Nepal, and Bhutan to the north; and Bangladesh and Myanmar to the east. In the Indian Ocean, India is near Sri Lanka and the Maldives; its Andaman and Nicobar Islands share a maritime border with Thailand, Myanmar, and Indonesia. Modern humans arrived on the Indian subcontinent from Africa no later than 55,000 years ago., "Y-Chromosome and Mt-DNA data support the colonization of South Asia by modern humans originating in Africa. ... Coalescence dates for most non-European populations averag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper
Copper is a chemical element; it has symbol Cu (from Latin ) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish-orange color. Copper is used as a conductor of heat and electricity, as a building material, and as a constituent of various metal alloys, such as sterling silver used in jewelry, cupronickel used to make marine hardware and coins, and constantan used in strain gauges and thermocouples for temperature measurement. Copper is one of the few metals that can occur in nature in a directly usable, unalloyed metallic form. This means that copper is a native metal. This led to very early human use in several regions, from . Thousands of years later, it was the first metal to be smelted from sulfide ores, ; the first metal to be cast into a shape in a mold, ; and the first metal to be purposely alloyed with another metal, tin, to create bronze, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brass
Brass is an alloy of copper and zinc, in proportions which can be varied to achieve different colours and mechanical, electrical, acoustic and chemical properties, but copper typically has the larger proportion, generally copper and zinc. In use since prehistoric times, it is a substitutional alloy: atoms of the two constituents may replace each other within the same crystal structure. Brass is similar to bronze, a copper alloy that contains tin instead of zinc. Both bronze and brass may include small proportions of a range of other Chemical element, elements including arsenic, lead, phosphorus, aluminium, manganese and silicon. Historically, the distinction between the two alloys has been less consistent and clear, and increasingly museums use the more general term "list of copper alloys, copper alloy". Brass has long been a popular material for its bright gold-like appearance and is still used for drawer pulls and door handle, doorknobs. It has also been widely used to ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antiseptic
An antiseptic ( and ) is an antimicrobial substance or compound that is applied to living tissue to reduce the possibility of sepsis, infection, or putrefaction. Antiseptics are generally distinguished from ''antibiotics'' by the latter's ability to safely destroy bacteria within the body, and from ''disinfectants'', which destroy microorganisms found on non-living objects. Antibacterials include antiseptics that have the proven ability to act against bacteria. Microbicides which destroy virus particles are called viricides or antivirals. Antifungals, also known as antimycotics, are pharmaceutical fungicides used to treat and prevent mycosis (fungal infection). Surgery Antiseptic practices evolved in the 19th century through multiple individuals. Ignaz Semmelweis showed already in 1847-1848 that hand washing prior to delivery reduced puerperal fever. Despite this, many hospitals continued to practice surgery in unsanitary conditions, with some surgeons taking pride in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shampoo
Shampoo () is a hair care product, typically in the form of a viscous liquid, that is formulated to be used for cleaning (scalp) hair. Less commonly, it is available in solid bar format. (" Dry shampoo" is a separate product.) Shampoo is used by applying it to wet hair, massaging the product in the hair, roots and scalp, and then rinsing it out. Some users may follow a shampooing with the use of hair conditioner. Shampoo is typically used to remove the unwanted build-up of sebum (natural oils) in the hair without stripping out so much as to make hair unmanageable. Shampoo is generally made by combining a surfactant, most often sodium lauryl sulfate or sodium laureth sulfate, with a co-surfactant, most often cocamidopropyl betaine in water. The sulfate ingredient acts as a surfactant, trapping oils and other contaminants, similarly to soap. Shampoos are marketed to people with hair. There are also shampoos intended for animals that may contain insecticides or other medica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dandruff
Dandruff is a skin condition of the scalp. Symptoms include flaking and sometimes mild itchiness. It can result in social or self-esteem problems. A more severe form of the condition, which includes inflammation of the skin, is known as seborrhoeic dermatitis. The cause is unclear, but believed to involve a number of genetic and environmental factors; the condition may worsen in the winter. It is not due to poor hygiene, and the underlying mechanism involves the excessive growth of skin cells. Diagnosis is based on symptoms. There is no known cure for dandruff. Antifungal cream, such as ketoconazole, or the keratolytic agent salicylic acid may be used to try to improve the condition. Dandruff affects about half of adults, with males more often affected than females. In addition, people in all areas of the world are affected. Onset is usually at puberty, and it becomes less common after the age of 50. Etymology According to the ''Oxford English Dictionary'', the wo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calamine
Calamine, also known as calamine lotion, is a medication made from powdered calamine (mineral), calamine mineral that is used to treat mild itchiness. Conditions treated include sunburn, insect bites, Toxicodendron radicans, poison ivy, poison oak, and other mild skin conditions. It may also help dry out secretions resulting from skin irritation. It is applied on the skin as a cream (pharmaceutical), cream or lotion. Side effects may include skin irritation. It is considered to be safe in pregnancy. Calamine is a combination of zinc oxide and 0.5% iron(III) oxide, ferric oxide (Fe2O3). The lotion is produced with additional ingredients such as phenol and calcium hydroxide. The use of calamine lotion dates back as far as 1500 BC. It is on the WHO Model List of Essential Medicines, World Health Organization's List of Essential Medicines. Calamine is available over-the-counter as a generic medication. Medical uses Calamine is used to treat itchiness. This includes sunburn, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
