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Distribution natural

Gypsum is widely distributed naturally as calcium sulfate dihydrate [101012-1-4], CaS04-2H2 0. When partially calcined, the hemihydrate, CaS04 H2 0, is formed (see Calciumcompounds-calciumsulfates). Gypsum has been used in one form since 1756 for making dental casts, and in another form since 1844 for dental impressions (101). [Pg.475]

Flavones. These compounds are the most widely distributed natural coloring matter formerly used as dyestuffs. The term flavone was first suggested in 1895 (69), and is indicative of their yellow color ijlavus, Latin for yellow). They have lost their commercial value as dyes since the advent of synthetic dyes in 1856. [Pg.398]

We need this speeial algebra to operate on the engineering equations as part of probabilistie design, for example the bending stress equation, beeause the parameters are random variables of a distributional nature rather than unique values. When these random variables are mathematieally manipulated, the result of the operation is another random variable. The algebra has been almost entirely developed with the applieation of the Normal distribution, beeause numerous funetions of random variables are normally distributed or are approximately normally distributed in engineering (Haugen, 1980). [Pg.149]

A possible layered precursor to the layered nanoproduct conversion mechanism is thus proposed. The silver clusters formed at the initial heating stage by the partial decomposition of AgSR serve as nuclei at further reaction stages, and their distribution naturally inherits the layered pattern of the precursor. The following growth is mainly controlled by the atom concentration and atom diffusion path, which are both constrained by the crystal structure of the precursor [9]. [Pg.302]

In the practice of solid-state bioEPR, a Lorentzian line shape will be observed at relatively high temperatures and its width as a function of temperature can be used to deduce relaxation rates, while a Gaussian line will be observed at relatively low temperatures and its linewidth contains information on the distributed nature of the system. What exactly is high and low temperature, of course, depends on the system for the example of low-spin cytochrome a in Figure 4.2, a Lorentzian line will be observed at T = 80°C, and a Gaussian line will be found at T 20°C, while at T 50°C a mixture (a convolution) of the two distributions will be detected. [Pg.60]

Pieroni, J., Miller, D., Premont, R. T. and Lyengar, R. Type-5 adenylyl cyclase distribution. Nature 363 679, 1993. [Pg.376]

Many studies have been performed in laboratory animals to better characterize the distribution, nature, regulation, kinetic properties, and substrate specificity of aspirin hydrolases, as they are sometimes designated (e.g., [41] [84-86]). [Pg.405]

Macromolecular engineering is the ultimate goal of the polymer chemist when he has a monomer or a family of monomers at his disposal. Once each step of the polymerization process is carefully controlled, every molecular parameter of the polymer is predictable molecular weight, tacticity, molecular weight distribution, nature of the end groups, microstructure, and composition, and block... [Pg.21]

M9. Martin, B. K., Potential effect of the plasma proteins on drug distribution. Nature (London) 207, 274-276 (1965). [Pg.103]

Cresols are widely distributed natural compounds. As discussed above, they are formed as metabolites of microbial activity and are excreted in the urine of mammals (Fiege and Bayer 1987) and humans (Needham et al. 1984). Cresols from human urine are probably biodegraded at municipal sewage treatment facilities prior to release to ambient waters. However, for combined septic and storm sewage systems, cresols may be released to surface waters during periods of precipitation when influent volumes exceed treatment plant capacities. Also, in rural and suburban areas where septic tanks are used (o- and m-cresols can resist anaerobic digestion), human excrement may be a nonpoint source release of cresols to groundwater. [Pg.96]

As discussed above, cresols are widely distributed natural compounds. They are formed as metabolites of microbial activity and are excreted in the urine of mammals. Various plant lipid constituents, including many oils, contain cresols. Cresols have also been detected in certain foods and beverages such as tomatoes, tomato ketchup, cooked asparagus, various cheeses, butter, oil, red wine, distilled spirits, raw and roasted coffee, black tea, smoked foods, tobacco, and tobacco smoke (Fiege and Bayer 1987). However, very few monitoring data for cresols in food were found in the literature. [Pg.126]

Chlorinated aliphatic compounds are globally distributed. Natural product organohalides such as chloromethane and chloramphenicol are probably produced in diverse soil environments. Many halogenated organic compounds are biosynthesized by marine organisms (Neidleman Geigert, 1986), so the oceans area source as well. [Pg.301]

Cellulose is one of the most widely distributed natural polymers, since it is one of the principal components of vegetable tissue. It always occurs in nature in the form of fibres varying from the knap-like fibres covering cotton seeds, to the woody substance of trees. The name cellulose is used both for cellulose isolated from the plant, and thus a chemical compound, and for cellulose in situ in the form normally occurring in the plant. In the second case cellulose together with hemicelluloses and lignin form the main constituents of the plant. [Pg.215]

In the next two chapters of this book we turn to the chemical reactor that is probably the most challenging the tubular or plug flow reactor. The inherent distributed nature of the unit (variables change with axial and radial position) gives rise to complex behavior, which is often counterintuitive and difficult to explain. The increase in the number of independent variables makes the development and solution of mathematical models more complex compared to the perfectly mixed CSTR and batch reactor. [Pg.251]

The distributed nature of the tubular plug flow reactor means that variables change with both axial position and time. Therefore the mathematical models consist of several simultaneous nonlinear partial differential equations in time t and axial position z. There are several numerical integration methods for solving these equations. The method of lines is used in this chapter.1... [Pg.287]

The parison is inflated fast, within seconds or less, at a predetermined rate such that it does not burst while expanding. It is a complex process that involves expansion of a nonuniform membrane-like element. Because the extension ratio is high (above 10), it is difficult to calculate the final thickness distribution. Naturally, much of the recent theoretical research on parison stretching and inflation (as in the case with thermoforming) focuses on FEM methods and the selection of the appropriate rheological constitutive models to predict parison shape, thickness, and temperature distribution during the inflation. [Pg.853]

Chlorine, bromine and iodine are elements that are widely distributed naturally and form part of a range of processes, everything from biological through industrial. Each has at least one isotope that is nuclear magnetic resonance (NMR) active, and hence there is the opportunity to... [Pg.64]

The trade-offs among process design, optimization and control must be considered. The hierarchical or distributed nature of the plant or process may need to be exploited in an advanced control scheme. The operation of energy-integrated plants requires design of control systems which are decentralized (such as with microprocessors) but which respond to overall plant objectives via a communication link to a larger computer. [Pg.96]

Amino sugars are widely distributed naturally. Generally, they are sugars in which a hydroxyl group has been replaced by an amino group. [Pg.42]


See other pages where Distribution natural is mentioned: [Pg.31]    [Pg.172]    [Pg.542]    [Pg.26]    [Pg.277]    [Pg.278]    [Pg.10]    [Pg.300]    [Pg.2]    [Pg.18]    [Pg.198]    [Pg.628]    [Pg.40]    [Pg.40]    [Pg.128]    [Pg.95]    [Pg.7]    [Pg.272]    [Pg.1601]    [Pg.73]    [Pg.708]    [Pg.834]    [Pg.369]    [Pg.332]    [Pg.66]    [Pg.346]    [Pg.23]    [Pg.435]    [Pg.212]    [Pg.67]   
See also in sourсe #XX -- [ Pg.36 ]




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Deconvolution of Natural Isotope Distributions

Distributed in nature

Distribution natural, packed columns

Distribution of Unconventional Natural Shale Gas

Electronic distribution atomic natural charges

Natural abundance distribution

Natural gas distribution

Natural gas distribution system

Natural gas, transportation, distribution

Natural organic carbon-water distribution

Natural organic carbon-water distribution ratio

Natural rubber crosslink distribution

Pipes for natural gas distribution

Residence time distribution nature

Solute distribution, natural water freezing

Sources of natural hydrocarbons in the marine environment some processes controlling their distribution

The Nature and Size Distribution of Milk Fat Globules

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