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e. The Oxford–AstraZeneca COVID‑19 vaccine, sold under the brand names Covishield [31] and Vaxzevria [1] [32] among others, is a viral vector vaccine for the prevention of COVID-19. It was developed in the United Kingdom by Oxford University and British-Swedish company AstraZeneca, [33] [34] [35] using as a vector the modified chimpanzee ...
Botulinum toxin, or botulinum neurotoxin (commonly called botox), is a highly potent neurotoxic protein produced by the bacterium Clostridium botulinum and related species.[23] It prevents the release of the neurotransmitter acetylcholine from axon endings at the neuromuscular junction, thus causing flaccid paralysis.[24] The toxin causes the ...
- Synthesis
- Structure
- Physical Properties
- Applications
- Further Reading
Na0.5Bi0.5TiO3 is not a naturally occurring mineral and several synthesis routes to obtain the compound have been developed. It can be easily prepared by solid state reaction between Na2CO3, Bi2O3 and TiO2at temperatures around 850 °C.
The exact room-temperature crystal structure of sodium bismuth titanate has been a matter of debate for several years. Early studies in the 1960s using X-ray diffraction suggested Na0.5Bi0.5TiO3 to adopt either a pseudo-cubic or a rhombohedral crystal structure. In 2010, based on the high-resolution single-crystal X-ray diffraction data, a monoclin...
Na0.5Bi0.5TiO3 is a relaxor ferroelectric. Its optical band gap was reported to be in the 3.0–3.5 eV.
Various solid solutions with tetragonal ferroelectric perovskites including BaTiO3, Bi0.5K0.5TiO3 have been developed to obtain morphotropic phase boundaries to enhance the piezoelectric properties of Na0.5Bi0.5TiO3. The extraordinarily large strain generated by a field-induced phase transition in sodium bismuth titanate-based solid solutions promp...
Lead-Free Piezoelectrics, Ed. Shashank Priya and Sahn Nahm,(2012), Springer-Verlag, New York. doi:10.1007/978-1-4419-9598-8.
according to International Monetary Fund estimates [n 1] [1] Countries by nominal GDP in 2019 [n 2] > $20 trillion. $10–20 trillion. $5–10 trillion. $1–5 trillion. $750 billion – $1 trillion. $500–750 billion. $250–500 billion.
en.wikipedia.org
The number π (/paɪ/; spelled out as "pi") is a mathematical constant that is the ratio of a circle's circumference to its diameter, approximately equal to 3.14159. The number π appears in many formulae across mathematics and physics. It is an irrational number, meaning that it cannot be expressed exactly as a ratio of two integers, although ...
Georges Creek. The Bicentennial National Trail (BNT), originally known as the National Horse Trail, [1] is one of the longest multi-use, non-motorised, self-reliant trails in the world, stretching 5,330 kilometres from Cooktown, Queensland, through New South Wales and the Australian Capital Territory to Healesville, 60 km north-east of Melbourne.
