Crabs

Central Interim Storage Facilityfor NuclearFuel—CRAB, Swedish Nuclear Fuel and Waste Management Company (SKB), Stockholm, Sweden, 1986. 

Fig. 6. Approaches to minimising entrapment and impingement of fish and large aquatic invertebrates, eg, blue crabs, on trash screens at intakes, (a) An inlet pump house with vertical traveling screens mounted flush with a river shoreline to minimise obstmctions to animal movements (b) parallel flow to direct fish to a recovery chamber that returns to the water body (c) a velocity cap atop a vertical, offshore inlet induces a horizontal flow which fish avoid...

In one biosensor design, the chem preceptive nerve fibers of the anteimules of the blue crab Callinectes sapidus are coimected to a micropipet electrode. This assembly has been termed a receptrode (2). The receptrode created from Callinectes sapidus responds to the presence of amino acids (1) (qv) in concentrations as low as 10 M. 

It has been shown by IR-spectroscopic investigations which evidence on the appearance of new absorption bands after chitosan introducing, elementary analyses data. (N, occurrence in the samples, which quantity depends on chitosan nature and isolation conditions) It leads to significant increase of sorption capacity and specific surface of sorbents, which contain chitosan from silk waren chrysalises. Where as these parameters decrease for sorbents with chitosan from crabs. Evidently it is connected to more dense structure of the last one. It has been shown, that yield of sorbent on the base of PES and chitosan obtained by sol-gel method has depended significantly on such factors as components ratio, temperature, catalyst quantity etc. 

Last years the concern of the scientists and contributors to chitin, chitosan and chitincontaining connections has increased. It is connected to their widespread occurrence in the nature, paiticulai properties, and also feasibility in many areas of a national economy. The raw sources for obtaining chitincontaining of products are the testas of crabs, lobsters, shrimps, and also cabbage-weeds, funguses. 

The effects of cadmium may be modulated by environmental factors, including salinity and the presence of other compounds. The synergistic inhibition of limb regeneration in the hermit crab Uca pugilator caused by combinations of cadmium and methylmerciiry is only evident in water of high salinity. ... 

Two hundred grams of eleaned and dried crab shells (Note 1) ground to a fine powder is placed in a 2-1. beaker, and an excess of dilute (approximately 6 N) commercial hydrochloric acid is added slowly to the powdered material until no further action is evident. Much frothing occurs during the addition of the acid, and care must be exercised to avoid loss of material due to foaming over the sides of the beaker. After the reaction has subsided, the reaction mixture is allowed to stand from 4 to 6 hours to ensure complete removal of calcium carbonate. The residue is then filtered, washed with water until neutral to litmus, and dried in an oven at 50-60°. The weight of dried chitin is usually about 70 g., but with some lots of crab shells it may be as low as 40 g. 

The cleaned and dried crab shells were obtained from Carter and Lanhardt Company, Eleventh and Main Avenue, S.W., Washington, D. C. 

The preparation of glucosamine hydrochloride from lobster shells and crab shells by essentially this method has been reported by Irvine, McNicoll, and Hynd and Hudson and Dale. Other methods involving the use of cicad larvae shells and shrimp shells ls also have been reported. 

The crown esters are actually macrocyclic lactones, the bulk of which rings are ethyl-eneoxy units. By far, the largest number of such compounds have been prepared by Bradshaw and his co-workers. Representative examples of such compounds are shown below. The name crab ethers has occasionally been applied to such structures, but as with the aquatic species noted above, this name has not found wide acceptance. 

Couvert, n. envelope cover, crabbecht, a. Textiles) fast to crabbing. Crackbenzin, n. benzine or gasoline produced by cracking. 

Holz, n. wood timber forest thicket, -abfall, m., -abfdlle, rn.pl. wood waste, holzahnlich, a. wood-like, ligneous. Holz-alkohol, m. wood alcohol, -amiant, m ligneous asbestos, -apfel, m. crab apple, -apfelwein, m. crab cider, -art, /. kind or species of wood. 

Krabbe,/. crab shrimp, krabbecht, a. fast to crabbing, krahbeln, v.t. tickle. — v.i. itch crawl, krabben, v.t. (Textiles) crab. 

Erebs, m. cancer crayfish grain, hard particle (in clay, etc.) knot (in ore, etc.) wart canker crab crustacean. 

Taschen-ausgabe, /. pocket edition, -buch, n. pocket book, -filter, n. bag filter, -format, n. pocket size, -krebs, m. common crab, -lampe, /. pocket lamp, (pocket) flashlight, -lupe, /, pocket lens, -spiel, n. jugglery, -tuch, n. pocket handkerchief, -uhr, /. watch. 

Some ligands have more than one atom with an unshared pair of electrons and hence can form more than one bond with a central metal atom. Ligands of this type are referred to as chelating agents the complexes formed are referred to as chelates (from the Greek chela, crab s claw). Two of the most common chelating agents are the oxalate anion (abbreviated ox) and the ethylenediamine molecule (abbreviated en), whose Lewis structures are... 

Zn2+ 3000 mg 15 mg Component of many enzymes, hormones Oysters, crab, meat nuts... 

Chelant from Chela, the claw of a crab, lobster, or scorpion, and, in this context, meaning to hold apart). 

Tetrasodium pyrophosphate is used as a pH buffer (a substance that maintains a particular acidity level), and as a dough conditioner in soy-based meat alternatives. It promotes binding of proteins to water, binding the soy particles together, and is used for the same purpose in chicken nuggets and imitation crab and lobster products. 

The word chelating comes from the Latin word for claws, chelae, like the claws of a crab. A chelating agent grabs on to another molecule, like a crab s claw, and prevents it from reacting with other molecules. 

In spite of the alteration due to deacetylation, chitosan from crab tendon possesses a crystal structure showing an orthorhombic unit cell with dimensions a = 0.828, b = 0.862 and c = 1.043 nm (fiber axis). The unit cell comprises four glucosamine units two chains pass through the unit cell with an antiparallel packing arrangement. The main hydrogen bonds are 03 05 (intramolecular) and N2 06 (intermolecular) [82]. This material has also found medical uses (below). 

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