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Volumetric Flask
A volumetric flask (measuring flask or graduated flask) is a piece of laboratory apparatus, a type of laboratory flask, calibrated to contain a precise volume at a certain temperature. Volumetric flasks are used for precise dilutions and preparation of standard solutions. These flasks are usually pear-shaped, with a flat bottom, and made of glass or plastic. The flask's mouth is either furnished with a plastic snap/screw cap or fitted with a joint to accommodate a PTFE or glass stopper. The neck of volumetric flasks is elongated and narrow with an etched ring graduation marking. The marking indicates the volume of liquid contained when filled up to that point. The marking is typically calibrated "to contain" (marked "TC" or "IN") at 20 °C and indicated correspondingly on a label. The flask's label also indicates the nominal volume, tolerance, precision class, relevant manufacturing standard and the manufacturer's logo. Volumetric flasks are of various sizes, containing fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brand Volumetric Flask 100ml
A brand is a name, term, design, symbol or any other feature that distinguishes one seller's goods or service from those of other sellers. Brands are used in business, marketing, and advertising for recognition and, importantly, to create and store value as brand equity for the object identified, to the benefit of the brand's customers, its owners and shareholders. Brand names are sometimes distinguished from Generic brand, generic or store brands. The practice of branding—in the original literal sense of marking by burning—is thought to have begun with the ancient Egyptians, who are known to have engaged in livestock branding and branded slaves as early as 2,700 BCE. Branding was used to differentiate one person's cattle from another's by means of a distinctive symbol burned into the animal's skin with a hot branding iron. If a person stole any of the cattle, anyone else who saw the symbol could deduce the actual owner. The term has been extended to mean a strategic person ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GOST
GOST () refers to a set of international technical standards maintained by the Euro-Asian Council for Standardization, Metrology and Certification (EASC), a regional standards organization operating under the auspices of the Commonwealth of Independent States (CIS). All sorts of regulated standards are included, with examples ranging from charting rules for design documentation to recipes and nutritional facts of Soviet-era brand names. The latter have become generic, but may only be sold under the label if the technical standard is followed, or renamed if they are reformulated. History GOST standards were originally developed by the government of the Soviet Union as part of its national standardization strategy. The word GOST ( Russian: ) is an acronym for ''gosudarstvennyy standart'' (Russian: '), which means ''government standard''. The history of national standards in the USSR can be traced back to 1925, when a government agency, later named Gosstandart, was establi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Burette
A burette (also spelled buret) is a graduated glass tube with a tap at one end, for delivering known volumes of a liquid, especially in titrations. It is a long, graduated glass tube, with a stopcock at its lower end and a tapered capillary tube at the stopcock's outlet. The flow of liquid from the tube to the burette tip is controlled by the stopcock valve. There are two main types of burette; the volumetric burette and the piston burette. A volumetric burette delivers measured volumes of liquid. Piston burettes are similar to syringes, but with a precision bore and a plunger. Piston burettes may be manually operated or may be motorized. A weight burette delivers measured weights of a liquid. Overview A burette is a volumetric measuring glassware which is used in analytical chemistry for the accurate dispensing of a liquid, especially of one of the reagents in a titration. The burette tube carries graduated marks from which the dispensed volume of the liquid can be determi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Babcock Bottle
A Babcock bottle is a clear glass flask with a long graduated neck, used in the Babcock test to evaluate the cream contents of milk. It is also called a Babcock milk test bottle, milk test bottle, cream test bottle, and other similar names.Babcock milk testing bottle . Item 2014.0223.06, Online catalog, Smithsonian Institution. Accessed on 2019-03-04.(2019): Babcock cream testing bottle . Item 2014.0223.05, online catalog, National Museum of American History. Accessed on 2019-03-05.Ernest O. Herreid (1942): "The Babcock Test; A Review of the Literature". ''Journal of Dairy Science'', volume 25, issue 4, pages 342–343. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Graduated Cylinder
A graduated cylinder, also known as a measuring cylinder or mixing cylinder, is a common piece of laboratory equipment used to measure the volume of a liquid. It has a narrow cylindrical shape. Each marked line on the graduated cylinder represents the amount of liquid that has been measured. Materials and structure Large graduated cylinders are usually made of polypropylene for its excellent chemical resistance or polymethylpentene for its transparency, making them lighter and less fragile than glass. Polypropylene (PP) is easy to repeatedly autoclave; however, autoclaving in excess of about (depending on the chemical formulation: typical commercial grade polypropylene melts in excess of ), can warp or damage polypropylene graduated cylinders, affecting accuracy. A traditional graduated cylinder is usually narrow and tall so as to increase the accuracy and precision of volume measurement. It has a plastic or glass base (stand, foot, support) and a "spout" for easy pouring o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Specific Gravity
Relative density, also called specific gravity, is a dimensionless quantity defined as the ratio of the density (mass of a unit volume) of a substance to the density of a given reference material. Specific gravity for solids and liquids is nearly always measured with respect to water at its densest (at ); for gases, the reference is air at room temperature (). The term "relative density" (abbreviated r.d. or RD) is preferred in SI, whereas the term "specific gravity" is gradually being abandoned. If a substance's relative density is less than 1 then it is less dense than the reference; if greater than 1 then it is denser than the reference. If the relative density is exactly 1 then the densities are equal; that is, equal volumes of the two substances have the same mass. If the reference material is water, then a substance with a relative density (or specific gravity) less than 1 will float in water. For example, an ice cube, with a relative density of about 0.91, will float. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Food Chemistry
Food chemistry is the study of chemical processes and interactions of all biological and non-biological components of foods. The biological substances include such items as meat, poultry, lettuce, beer, milk as examples. It is similar to biochemistry in its main components such as carbohydrates, lipids, and protein, but it also includes areas such as water, vitamins, minerals, enzymes, food additives, flavors, and colors. This discipline also encompasses how products change under certain food processing techniques and ways either to enhance or to prevent them from happening. An example of enhancing a process would be to encourage fermentation of dairy products with microorganisms that convert lactose to lactic acid; an example of preventing a process would be stopping the browning on the surface of freshly cut apples using lemon juice or other acidulated water. History of food chemistry The scientific approach to food and nutrition arose with attention to agricultural chemistry ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Analytical Chemistry
Analytical skill, Analytical chemistry studies and uses instruments and methods to Separation process, separate, identify, and Quantification (science), quantify matter. In practice, separation, identification or quantification may constitute the entire analysis or be combined with another method. Separation isolates analytes. Qualitative inorganic analysis, Qualitative analysis identifies analytes, while Quantitative analysis (chemistry), quantitative analysis determines the numerical amount or concentration. Analytical chemistry consists of classical, wet chemistry, wet chemical methods and modern analytical techniques. Classical qualitative methods use separations such as Precipitation (chemistry), precipitation, Extraction (chemistry), extraction, and distillation. Identification may be based on differences in color, odor, melting point, boiling point, solubility, radioactivity or reactivity. Classical quantitative analysis uses mass or volume changes to quantify amount. Ins ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sugar Beet
A sugar beet is a plant whose root contains a high concentration of sucrose and that is grown commercially for sugar production. In plant breeding, it is known as the Altissima cultivar group of the common beet (''Beta vulgaris''). Together with other beet cultivars, such as beetroot and chard, it belongs to the subspecies ''Beta vulgaris'' subsp. ''vulgaris'' but classified as ''var. saccharifera''. Its closest wild relative is the sea beet (''Beta vulgaris'' subsp. ''maritima''). Sugar beets are grown in climates that are too cold for sugarcane. In 2020, Russia, the United States, Germany, France and Turkey were the world's five largest sugar beet producers. In 2010–2011, Europe, and North America except Arctic territories failed to supply the overall domestic demand for sugar and were all net importers of sugar. The US harvested of sugar beets in 2008. In 2009, sugar beets accounted for 20% of the world's sugar production and nearly 30% by 2013. Sugarcane accounts for most ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitamin A
Vitamin A is a fat-soluble vitamin that is an essential nutrient. The term "vitamin A" encompasses a group of chemically related organic compounds that includes retinol, retinyl esters, and several provitamin (precursor) carotenoids, most notably Β-Carotene, β-carotene (''beta''-carotene). Vitamin A has multiple functions: growth during embryo development, maintaining the immune system, and healthy vision. For aiding vision specifically, it combines with the protein opsin to form rhodopsin, the light-absorbing molecule necessary for both low-light (scotopic vision) and color vision. Vitamin A occurs as two principal forms in foods: A) retinoids, found in Animal source foods, animal-sourced foods, either as retinol or bound to a fatty acid to become a retinyl ester, and B) the carotenoids Α-Carotene, α-carotene (''alpha''-carotene), β-carotene, Γ-Carotene, γ-carotene (''gamma''-carotene), and the xanthophyll beta-cryptoxanthin (all of which contain β-ionone rings) that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silver Nitrate
Silver nitrate is an inorganic compound with chemical formula . It is a versatile precursor to many other silver compounds, such as those used in photography. It is far less sensitive to light than the halides. It was once called ''lunar caustic'' because silver was called ''luna'' by ancient alchemists who associated silver with the moon. In solid silver nitrate, the silver ions are three- coordinated in a trigonal planar arrangement. Synthesis and structure Albertus Magnus, in the 13th century, documented the ability of nitric acid to separate gold and silver by dissolving the silver. Indeed silver nitrate can be prepared by dissolving silver in nitric acid followed by evaporation of the solution. The stoichiometry of the reaction depends upon the concentration of nitric acid used. :3 Ag + 4 HNO3 (cold and diluted) → 3 AgNO3 + 2 H2O + NO :Ag + 2 HNO3 (hot and concentrated) → AgNO3 + H2O + NO2 The structure of silver nitrate has been examined by X-ray crystallography se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Pharmacopeia
The ''United States Pharmacopeia'' (''USP'') is a pharmacopeia (compendium of drug information) for the United States published annually by the over 200-year old United States Pharmacopeial Convention (usually also called the USP), a nonprofit organization that owns the trademark and also owns the copyright on the pharmacopeia itself. The ''USP'' is published in a combined volume with the ''National Formulary'' (a formulary) as the USP-NF. If a drug ingredient or drug product has an applicable ''USP'' quality standard (in the form of a ''USP-NF'' monograph), it must conform in order to use the designation "USP" or "NF". Drugs subject to ''USP'' standards include both human drugs ( prescription, over-the-counter, or otherwise) and animal drugs. ''USP-NF'' standards also have a role in US federal law; a drug or drug ingredient with a name recognized in ''USP-NF'' is considered adulterated if it does not satisfy compendial standards for strength, quality, or purity. USP also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
