Dehydration, definition

The American Spice Trade Association (ASTA) (4) accepts spice as any dried plant product used primarily for seasoning purposes. This broad definition was designed so that items labeled only as spice could give adequate protection to proprietary formulas for spice mixtures. However, ASTA recommends that the dehydrated vegetables and the color spices be listed separately by name on all labels. ASTA also has recommended that the capsicums, no matter the species, be delisted as spices and labeled separately. 

For iridium the position is reversed. This time it is the black dioxide, Ir02, with the rutile structure (p. 961), which is the only definitely established oxide. It is obtained by heating the metal in oxygen or by dehydrating the precipitate produced when alkali is added to an aqueous solution of [IrCl6] . Contamination either by unreacted metal or by alkali is, however, difficult to avoid. The other oxide, Ir203, is said to be... 

The name, maleic anhydride, came about in the same fashion. as any number of compounds early in the petrochemical Business Many organic acids and their derivatives were given common names based on some early observations, their special source in nature, or on some special feature of their structure. MA was first isolated in the 1850—75 era by dehydration of malic acid, a sugar acid found in apple juice. The Latin word for apple is malum. Hence, malum, malic, maleic. The suffix, anhydride, which follows each alias of MA, has a simple definition a compound derived by the loss of a molecule of water from two carboxyl groups (-COOH). 

Often, it is difficult to distinguish definitely between inner sphere and outer sphere complexes in the same system. Based on the preceding discussion of the thermodynamic parameters, AH and AS values can be used, with cation, to obtain insight into the outer vs. inner sphere nature of metal complexes. For inner sphere complexation, the hydration sphere is disrupted more extensively and the net entropy and enthalpy changes are usually positive. In outer sphere complexes, the dehydration sphere is less disrupted. The net enthalpy and entropy changes are negative due to the complexation with its decrease in randomness without a compensatory disruption of the hydration spheres. 

Intravenous route is the most rapidly effective and the desired blood concentration can be obtained with a definite dose but at the same time it is the most dangerous route of administration. For once the drug is injected there is no retreat. So, intravenous injection must usually be performed slowly and with constant monitoring of the patient. This route is usually reserved for emergencies when a rapid action is required and infusion of large amounts of fluids to overcome dehydration or to supply nutrition to patients who can not take food/fluids orally. 

The nitrocellulose is then centrifuged to a definite alcohol content. The dehydration of one batch of nitrocellulose requires approximately 1 hr. 

Early History.—Although the destructive distillation of partially dehydrated sulphate such as alum was undoubtedly practised very early, even perhaps in the tenth century, the first definite details of the process emanated from Basil Valentine towards the end of the fifteenth century, who described the distillation of green vitriol with silica the name oil of vitriol is derived from this process. Basil Valentine also obtained an acid product by the combustion of a mixture of sulphur and saltpetre, the identity of this sulphuric add with oil of vitriol being first proved by A. Libavius in 1595. 

This latter reaction is very slow as written and is of more importance in the reverse, dehydration reaction.) The characterization of these metal and nonmetal oxides as acids and bases is of help in rationalizing the workings, for example, of a basic Bessemer converter in steetmatcing. The identification of these acidic and basic species will also prove useful in develop r a general definition of acid-base behavior. 

It is also of interest to use MAS NMR for the study of the thermal treatment of zeolites which are not in the ammonium-exchanged form. In an X-ray study, Pluth and Smith (179) found electron density at the center of the sodalite cages in dehydrated zeolites Ca-A and Sr-A and attributed this to a partial occupancy of these sites by a four-coordinated aluminous species. No such effect was found in zeolite A exchanged with monovalent cations. Corbin et al. (180) used 27A1 MAS NMR to examine commercial samples of K-A, Na-A and (Ca,Na)-A, as received (see Fig. 41). For K-A and Na-A, only framework tetrahedral Al species were observed, with chemical shifts of 57 and 52 ppm respectively. However, in (Ca,Na)-A an additional intense resonance at 78 ppm, typical of AlfOH) but definitely not due to framework aluminum, was also found (see Fig. 41). A much weaker signal, also at 78 ppm, was detected in zeolite Sr-A its intensity increased greatly on heating the sample to 550°C. Freude et al. (183) came to very similar conclusions in their NMR study of heat-treated zeolite Ca-A. They found that maximum framework dealumination occurs at 500°C and corresponds to ac. 17% of total Al. 

See under Siloxanes in article on Silanes in this Vol for the definition and a brief description of the basic molecular structure. The name silicone was created by F.S, Kipping as an analogy to ketones. However, his silicane-diols , (Aryl)2Si(OH)2 could not be dehydrated to silicones but always condensed to higher mw Si—0—Si compds. These structures were then (early 1900s) referred to as silicones. In time the name has come to represent any organo-silicon oxide polymer, such as polydimethy-siloxane (see below) ... 

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