"Stilbite" Natural Recordings by Native Speakers
Stilbite is a methyl-aluminosilicate mineral with the chemical formula NaCa4Si7Al9O24·12H2O. It is a rare mineral, typically found in hydrothermal veins and cavities in basalts. Stilbite has a clear or white color and a vitreous to glassy luster. It is relatively soft, with a Mohs hardness of about 4.5-5. It is often found in association with other zeolites.
Stilbite is named after the Scottish mineralogist James Douglas Stilbok, who discovered the mineral in 1822. It has a molecular structure composed of tetrahedron units of silicon, aluminum, and oxygen atoms. Stilbite is often used as a mineral specimen for educational purposes due to its attractive crystal formation.
The name "Stihl" refers to a German brand of chainsaws and outdoor power equipment. The name "Stihl" is derived from the founder's name, Andreas Stihl, who started the company in 1926.
Stilbenes are a class of organic compounds consisting of 1,2-diphenylethene (or ethane-1,2-diylidene) structure, which consists of two benzene rings linked by a three-carbon chain. Stilbenes typically have conjugated double bonds and often exhibit electronic and optical properties valuable for various applications.<br><br>Examples of stilbene compounds include:<br><br>1. Stilbene itself (C6H5CHCHC6H5)<br>2. Resveratrol (3,5,4'-trihydroxystilbene), a compound found in red wine, is said to have potential health benefits.<br>3. Prenyloxystilbene, a stilbene analog used as a colorant in certain food products.<br><br>Stilbenes can be categorized into different types based on their molecular structure, such as:<br><br>1. cis-stilbene and trans-stilbene (with the two benzene rings in the same or opposite positions, respectively)<br>2. angular stilbene (with the two benzene rings connected by a homocyclic joint<br>3. spirostilbene<br>4. other bridged stilbenes<br><br>Stilbenes find application in diverse fields, including:<br><br>1. Chemical synthesis<br>2. Organic chemistry research<br>3. Polymer science<br>4. Materials science<br>5. Photophysics and photochemistry<br>6. Pharmaceutical research<br><br>Their pharmacological and biological effects attract considerable research and attention, influencing various fields like nutraceuticals, ceramics, colorants, and polymer science. Stilbenes serve as relies for addressing numerous industrial, clinical, and environmental challenges and opportunities.
A woman's shoe with a long, thin heel and a pointed toe, often worn for formal occasions. It is often associated with glamour and sophistication.