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Erlenmeyer flask

An Erlenmeyer flask known as a conical flask or a titration flask, is a type of laboratory flask which features a flat bottom, a conical body, a cylindrical neck. It is named after the German chemist Emil Erlenmeyer, who created it in 1860. Erlenmeyer flasks have wide bases, with sides, they may be graduated, spots of ground glass or enamel are used where they can be labeled with a pencil. It differs from the beaker in narrow neck. Depending on the application, they may be constructed from glass or plastic, in a wide range of volumes; the mouth of the Erlenmeyer flask may have a beaded lip that can be covered. Alternatively, the neck may be fitted with ground glass or other connector for use with more specialized stoppers or attachment to other apparatus. A Büchner flask is a common design modification used for filtration under vacuum; the slanted sides and narrow neck of this flask allow the contents of the flask to be mixed by swirling, without risk of spillage, making them suitable for titrations by placing it under the buret and adding solvent and the indicator in Erlenmeyer flask.

Such features make the flask suitable for boiling liquids. Hot vapor condenses on the upper section of the Erlenmeyer flask, reducing solvent loss. Erlenmeyer flasks' narrow necks can support filter funnels; the final two attributes of Erlenmeyer flasks make them appropriate for recrystallization. The sample to be purified is heated to a boil, sufficient solvent is added for complete dissolution; the receiving flask is filled with a small amount of solvent, heated to a boil. The hot solution is filtered through a fluted filter paper into the receiving flask. Hot vapors from the boiling solvent keep the filter funnel warm, avoiding the premature crystallization. Like beakers, Erlenmeyer flasks are not suitable for accurate volumetric measurements, their stamped volumes are approximate within about 5% accuracy. Erlenmeyer flasks are used in microbiology for the preparation of microbial cultures. Erlenmeyer flasks used in cell culture are sterilized and may feature vented closures to enhance gas exchange during incubation and shaking.

The use of minimal liquid volumes no more than one fifth of the total flask volume, baffles molded into the flask's internal surface both serve to maximize gas transfer and promote chaotic mixing when the flasks are orbitally shaken. The oxygen transfer rate in Erlenmeyer flasks depends on the agitation speed, the liquid volume, the shake-flask design; the shaking frequency has the most significant impact on oxygen transfer. Oxygenation and mixing of liquid cultures further depend on rotation of the liquid "in-phase", meaning the synchronous movement of the liquid with the shaker table. Under certain conditions the shaking process leads to a breakdown of liquid motion – called "out-of-phase phenomenon"; this phenomenon has been intensively characterized for shake flask bioreactors. Out-of-phase conditions are associated with a strong decrease in mixing performance, oxygen transfer, power input. Main factor for out-of-phase operation is the viscosity of the culture medium, but the vessel diameter, low filling levels and/or a high number of baffles.

To impede illicit drug manufacturers, the state of Texas restricted the sale of Erlenmeyer flasks to those who have the requisite permits. On September 1, 2019, SB 616 amended the law so that permits are no longer required, but accurate inventory of this and certain other pieces of lab equipment must still be maintained, loss or theft must still be reported, the owner must still allow audits of their records and equipment to be made. Fleaker Florence flask

You're My Best Friend (Don Williams album)

You're My Best Friend is the fourth LP by American country singer and songwriter Don Williams. Released in April 1975 on the ABC-Dot label, the album reached number five on the US Country Albums chart. "You're My Best Friend" and " Love Me Tonight" were released as singles in 1975, both reaching number one on the Billboard country singles chart. The previous year, Don Williams achieved his first number-one single with the song "I Wouldn't Want to Live If You Didn't Love Me", he teamed up again with regular collaborators, including Bob McDill, Allen Reynolds, Dickey Lee and Wayland Holyfield to craft another chart success. From the original vinyl Side A "You're My Best Friend" - 2:43 "Help Yourselves to Each Other" - 2:29 "I Don't Wanna Let Go" - 3:12 "Sweet Fever" - 2:17 "Someone Like You" - 3:02Side B " Love Me Tonight" - 2:18 "Where Are You" - 2:51 "Tempted" - 3:27 "You're the Only One" - 2:44 "Reason to Be" - 3:02

Society to Save Rocks

Society to Save Rocks is a not-for-profit entity established in 1996 in Hyderabad, India by rocks enthusiasts with preservation motif those rock formations abutting the twin cities of Hyderabad and Secunderabad amidst the Deccan Plateau. Frauke Quader, Laxma Goud and others have been credited with the formation of the Society way back in the 1990s; as a Hyderabadi interested in preservation of the rocks, Frauke Quader has much to share about the importance of the rocks, Rock walks and Hyderabad Rockathon are two focal activities of the Society that add visibility to its initiative to create interest. Since the past couple of years', the Society has been associating itself with the Hyderabad Literary Festival as a partner and exhibiting rock photos and conducting rock walks on the sidelines of the festival on the precincts of the Hyderabad Public School, Begumpet. In order to create a public awareness, rock walks are held on every third Sunday of the month to various rock formations around the twin cities of Hyderabad and Secunderabad as well as to the adjoining districts in Telangana.

A schedule of the rock walks are announced in advance each quarter and available on the web site of the Society. The society in association with Greater Hyderabad Adventure Club has been conducting Rockathon with the first one being held in the premises of the Hyderabad Central University way back in 2012. Syeda Imam. "The Untold Charminar: Writings on Hyderabad". ISBN -978-0143103707. M. Sarada. "Enrich your Grammar Word to Paragraph". ISBN 978-81-207-2365-8. Narendra Luther. "The Rockitecture of Andhra Pradesh"