|
Defatting (medical)
Defatting is the chemical dissolving of dermal lipids, from the skin, on contact with defatting agents. This can result in water loss from the affected area and cause the whitening and drying of the skin which may result in cracking, secondary infection and chemical irritant contact dermatitis. Cause Defatting is caused by the exposure of human skin to a chemical substance, including alcohols, detergents, chemical solvents and motor oil. Aliphatic compounds (commonly found in kerosene) cause defatting action, with lower-boiling point aliphatics having the greatest defatting action and therefore the most potential to cause dermatitis. Aromatic compounds, such as styrene, also have a defatting capacity. Prevention Defatting can be prevented by wearing appropriate protective clothing such as gloves, lab coats and aprons when working regularly with defatting agents. Prolonged skin contact or chronic defatting of the skin increases the possibility for developing irritant contact ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lipid
Lipids are a broad group of naturally-occurring molecules which includes fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E and K), monoglycerides, diglycerides, phospholipids, and others. The functions of lipids include storing energy, signaling, and acting as structural components of cell membranes. Lipids have applications in the cosmetic and food industries, and in nanotechnology. Lipids may be broadly defined as hydrophobic or amphiphilic small molecules; the amphiphilic nature of some lipids allows them to form structures such as vesicles, multilamellar/unilamellar liposomes, or membranes in an aqueous environment. Biological lipids originate entirely or in part from two distinct types of biochemical subunits or "building-blocks": ketoacyl and isoprene groups. Using this approach, lipids may be divided into eight categories: fatty acyls, glycerolipids, glycerophospholipids, sphingolipids, saccharolipids, and polyketides (derived from cond ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kerosene
Kerosene, paraffin, or lamp oil is a combustible hydrocarbon liquid which is derived from petroleum. It is widely used as a fuel in aviation as well as households. Its name derives from el, κηρός (''keros'') meaning "wax", and was registered as a trademark by Canadian geologist and inventor Abraham Gesner in 1854 before evolving into a generic trademark. It is sometimes spelled kerosine in scientific and industrial usage. The term kerosene is common in much of Argentina, Australia, Canada, India, New Zealand, Nigeria, and the United States, while the term paraffin (or a closely related variant) is used in Chile, eastern Africa, South Africa, Norway, and in the United Kingdom. The term lamp oil, or the equivalent in the local languages, is common in the majority of Asia and the Southeastern United States. Liquid paraffin (called mineral oil in the US) is a more viscous and highly refined product which is used as a laxative. Paraffin wax is a waxy solid extracted from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soap
Soap is a salt of a fatty acid used in a variety of cleansing and lubricating products. In a domestic setting, soaps are surfactants usually used for washing, bathing, and other types of housekeeping. In industrial settings, soaps are used as thickeners, components of some lubricants, and precursors to catalysts. When used for cleaning, soap solubilizes particles and grime, which can then be separated from the article being cleaned. In hand washing, as a surfactant, when lathered with a little water, soap kills microorganisms by disorganizing their membrane lipid bilayer and denaturing their proteins. It also emulsifies oils, enabling them to be carried away by running water. Soap is created by mixing fats and oils with a base. A similar process is used for making detergent which is also created by combining chemical compounds in a mixer. Humans have used soap for millennia. Evidence exists for the production of soap-like materials in ancient Babylon around 2800 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chronic Toxicity
Chronic toxicity, the development of adverse effects as a result of long term exposure to a contaminant or other stressor, is an important aspect of aquatic toxicology. Adverse effects associated with chronic toxicity can be directly lethal but are more commonly sublethal, including changes in growth, reproduction, or behavior. Chronic toxicity is in contrast to acute toxicity, which occurs over a shorter period of time to higher concentrations. Various toxicity tests can be performed to assess the chronic toxicity of different contaminants, and usually last at least 10% of an organism's lifespan. Results of aquatic chronic toxicity tests can be used to determine water quality guidelines and regulations for protection of aquatic organisms. Chronic toxicity definition Chronic toxicity is the development of adverse effects as the result of long term exposure to a toxicant or other stressor. It can manifest as direct lethality but more commonly refers to sublethal endpoints such as de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aprons
An apron is a garment that is worn over other clothing to cover the front of the body. The word comes from old French ''napron'' meaning a small piece of cloth, however over time "a napron" became "an apron", through a linguistics process called rebracketing. It may have several purposes, typically as a functional accessory that protects clothes and skin from stains and marks. However, other types of aprons may be worn as a decoration, for hygienic reasons, as part of a uniform, or as protection from certain dangers such as acid, allergens or excessive heat. It can also be used at work stations to hold extra tools and pieces or protect from dust and unwanted materials. As a top layer that covers the front body, the apron is also worn as a uniform, adornment, ceremonial garb (e.g. Masonic apron) or fashion statement. Apron styles can be practical, fashionable, and sentimental. Apron styles There are many different apron forms depending on the purpose of the apron. A basic dis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lab Coat
A white coat, also known as a laboratory coat or lab coat, is a knee-length overcoat or smock worn by professionals in the medical field or by those involved in laboratory work. The coat protects their street clothes and also serves as a simple uniform. The garment is made from white or light-colored cotton, linen, or cotton polyester blend, allowing it to be washed at high temperature and making it easy to see if it is clean. Similar coats are a symbol of learning in Argentina and Uruguay, where they are worn by both students and teachers in state schools. In Tunisia and Mozambique, teachers wear white coats to protect their street clothes from chalk. Like the word " suit", the phrase "white coat" is sometimes used as a metonym to denote the wearer, such as a scientist working in a high-tech company. Medicine White coats are sometimes seen as the distinctive dress of both physicians and surgeons, who have worn them for over 100 years. In the nineteenth century, respect for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gloves
A glove is a garment covering the hand. Gloves usually have separate sheaths or openings for each finger and the thumb. If there is an opening but no (or a short) covering sheath for each finger they are called fingerless gloves. Fingerless gloves having one small opening rather than individual openings for each finger are sometimes called gauntlets, though gauntlets are not necessarily fingerless. Gloves which cover the entire hand or fist but do not have separate finger openings or sheaths are called mittens. Mittens are warmer than other styles of gloves made of the same material because fingers maintain their warmth better when they are in contact with each other; reduced surface area reduces heat loss. A hybrid of glove and mitten contains open-ended sheaths for the four fingers (as in a fingerless glove, but not the thumb) and an additional compartment encapsulating the four fingers. This compartment can be lifted off the fingers and folded back to allow the individual f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Styrene
Styrene () is an organic compound with the chemical formula C6H5CH=CH2. This derivative of benzene is a colorless oily liquid, although aged samples can appear yellowish. The compound evaporates easily and has a sweet smell, although high concentrations have a less pleasant odor. Styrene is the precursor to polystyrene and several copolymers. Approximately 25 million tonnes of styrene were produced in 2010, increasing to around 35 million tonnes by 2018. Natural occurrence Styrene is named after storax balsam (often commercially sold as ''styrax''), the resin of Liquidambar trees of the Altingiaceae plant family. Styrene occurs naturally in small quantities in some plants and foods (cinnamon, coffee beans, balsam trees and peanuts) and is also found in coal tar. History In 1839, the German apothecary Eduard Simon isolated a volatile liquid from the resin (called ''storax'' or ''styrax'' (Latin)) of the American sweetgum tree (''Liquidambar styraciflua''). He called th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aliphatic Compound
In organic chemistry, hydrocarbons ( compounds composed solely of carbon and hydrogen) are divided into two classes: aromatic compounds and aliphatic compounds (; G. ''aleiphar'', fat, oil). Aliphatic compounds can be saturated, like hexane, or unsaturated, like hexene and hexyne. Open-chain compounds, whether straight or branched, and which contain no rings of any type, are always aliphatic. Cyclic compounds can be aliphatic if they are not aromatic. Structure Aliphatic compounds can be saturated, joined by single bonds (alkanes), or unsaturated, with double bonds (alkenes) or triple bonds ( alkynes). If other elements ( heteroatoms) are bound to the carbon chain, the most common being oxygen, nitrogen, sulfur, and chlorine, it is no longer a hydrocarbon, and therefore no longer an aliphatic compound. The least complex aliphatic compound is methane (CH4). Properties Most aliphatic compounds are flammable, allowing the use of hydrocarbons as fuel, such as metha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skin
Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation. Other animal coverings, such as the arthropod exoskeleton, have different developmental origin, structure and chemical composition. The adjective cutaneous means "of the skin" (from Latin ''cutis'' 'skin'). In mammals, the skin is an organ of the integumentary system made up of multiple layers of ectodermal tissue and guards the underlying muscles, bones, ligaments, and internal organs. Skin of a different nature exists in amphibians, reptiles, and birds. Skin (including cutaneous and subcutaneous tissues) plays crucial roles in formation, structure, and function of extraskeletal apparatus such as horns of bovids (e.g., cattle) and rhinos, cervids' antlers, giraffids' ossicones, armadillos' osteoderm, and os penis/ os clitoris. All mammals have some hair on their skin, even marine mammals like whales, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Motor Oil
Motor oil, engine oil, or engine lubricant is any one of various substances used for the lubrication of internal combustion engines. They typically consist of base oils enhanced with various additives, particularly antiwear additives, detergents, dispersants, and, for multi-grade oils, viscosity index improvers. The main function of motor oil is to reduce friction and wear on moving parts and to clean the engine from sludge (one of the functions of dispersants) and varnish (detergents). It also neutralizes acids that originate from fuel and from oxidation of the lubricant (detergents), improves sealing of piston rings, and cools the engine by carrying heat away from moving parts. In addition to the aforementioned basic constituents, almost all lubricating oils contain corrosion and oxidation inhibitors. Motor oil may be composed of only a lubricant base stock in the case of non-detergent oil, or a lubricant base stock plus additives to improve the oil's detergency, extreme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solvent
A solvent (s) (from the Latin '' solvō'', "loosen, untie, solve") is a substance that dissolves a solute, resulting in a solution. A solvent is usually a liquid but can also be a solid, a gas, or a supercritical fluid. Water is a solvent for polar molecules and the most common solvent used by living things; all the ions and proteins in a cell are dissolved in water within the cell. The quantity of solute that can dissolve in a specific volume of solvent varies with temperature. Major uses of solvents are in paints, paint removers, inks, and dry cleaning. Specific uses for organic solvents are in dry cleaning (e.g. tetrachloroethylene); as paint thinners ( toluene, turpentine); as nail polish removers and solvents of glue (acetone, methyl acetate, ethyl acetate); in spot removers ( hexane, petrol ether); in detergents ( citrus terpenes); and in perfumes (ethanol). Solvents find various applications in chemical, pharmaceutical, oil, and gas industries, including in chemic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> Aprons")
.jpg "Click for more on -> Gloves")
