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Fischer projections are commonly constructed beginning with a sawhorse representation. To do so, all attachments to main chain carbons must be rotated such that resulting Newman projections show an eclipsed configuration. The carbon chain is then positioned vertically upward with all horizontal attachments pointing toward the viewer.
Fischer–Tropsch process. The Fischer–Tropsch process (FT) is a collection of chemical reactions that converts a mixture of carbon monoxide and hydrogen, known as syngas, into liquid hydrocarbons. These reactions occur in the presence of metal catalysts, typically at temperatures of 150–300 °C (302–572 °F) and pressures of one to ...
In mathematical statistics, the Fisher information (sometimes simply called information) is a way of measuring the amount of information that an observable random variable X carries about an unknown parameter θ of a distribution that models X. Formally, it is the variance of the score, or the expected value of the observed information.
Electrofishing is a common scientific survey method used to sample fish populations to determine abundance, density and species composition. When performed correctly, electrofishing results in no permanent harm to the fish, which return to their natural mobility state in as little as two minutes after being caught. [1]
Fischer's lovebird has a fast flight, and the sound of their wings as they fly can be heard. Like all Lovebirds, they are very vocal and when they do make noise they have a high-pitched chirp and can be very noisy. Food and feeding. Fischer's lovebirds eat a wide variety of foods, including seeds and fruit.
History of fishing. Fishing is a prehistoric practice dating back at least 70,000 years. Since the 16th century, fishing vessels have been able to cross oceans in pursuit of fish, and since the 19th century it has been possible to use larger vessels and in some cases process the fish on board.
Fishing down the food web. Fishing down the food web is the process whereby fisheries in a given ecosystem, "having depleted the large predatory fish on top of the food web, turn to increasingly smaller species, finally ending up with previously spurned small fish and invertebrates ". [1]
from Maharashtra, India . The common kingfisher ( Alcedo atthis ), also known as the Eurasian kingfisher and river kingfisher, is a small kingfisher with seven subspecies recognized within its wide distribution across Eurasia and North Africa. It is resident in much of its range, but migrates from areas where rivers freeze in winter.
The Kiliani–Fischer synthesis, named for German chemists Heinrich Kiliani and Emil Fischer, is a method for synthesizing monosaccharides. It proceeds via synthesis and hydrolysis of a cyanohydrin, followed by reduction of the intermediate acid to the aldehyde, thus elongating the carbon chain of an aldose by one carbon atom while preserving ...
Commercial fishing is the activity of catching fish and other seafood for commercial profit, mostly from wild fisheries. It provides a large quantity of food to many countries around the world, but those who practice it as an industry must often pursue fish far into the ocean under adverse conditions. Large-scale commercial fishing is called ...