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Variable elevations

A sulfidic halo is characterized mostly by elevated S, Au, As and Sb. It extends further than suggested by previous alteration studies, and is defined by the development of disseminated hydrothermal pyrite and, to a lesser extent, arsenopyrite. Gold deposits of the Costerfield stibnite domain (i.e., Fosterville and Costerfield) can be differentiated from Au-As orogenic deposits by a greater primary dispersion of anomalous As and higher threshold values for Sb, as well as by the presence of slightly elevated concentrations of Hg (>0.01 ppm). Other chalcophile elements at variably elevated levels within the sulfidic alteration halo include Mo, Se, Bi, Pb and Cu. [Pg.274]

Type IV—A common disorder characterized by variable elevations of plasma triglycerides contained predominantly in VLDL. This leads to a possible predisposition to atherosclerosis and often has a familial distribution. [Pg.277]

The most commonly used indicators of hepatotoxicity (i.e., liver injury) are increased levels of the liver transaminases, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) (88,89). Drug-induced hepatotoxicity can develop rapidly, often before abnormal laboratory tests are noticed, which are characterized by rapid elevations in ALT and AST of 8 to 500 times the upper normal limit, with variable elevations in bilirubin. Drugs causing acute liver injury (hepatocellular necrosis) exhibit elevations in hepatic transaminases ranging from 50 to 100 times higher than the normal level. On the other hand, the elevations of ALT and AST in alcoholic liver disease are two- to three times higher than normal. Some hepatotoxins, however, do not elevate transaminases, whereas nonhepatic toxins can elevate ALT. [Pg.483]

Higher, Lower More, Less Process variable Elevation... [Pg.1431]

Serum creatine kinase (CK) levels variable elevated (less than 10 times normal), but may be normal cardiac troponin (cTn) is often elevated... [Pg.163]

The more noble metals (for example copper, mercury and silver) can form oxides, and exhibit variable oxidation state in such compounds (for example CU2O, CuO), but it is not easy to prepare such oxides by direct action of oxygen on the metal, and elevated temperatures are necessary. Moreover, in the case of silver and mercury, loss of oxygen from the oxide by heating is easy. The oxidesare, however, basic (for example Ag20 - Ag, CuO - Cu in acids). [Pg.286]

Note that this expression is equivalent to the barometric formula which gives the variation of atmospheric pressure ( c) with elevation (oc r). A first-order dependence on the distance variable holds in the barometric equation, since the acceleration is constant in this case. [Pg.639]

Variable-Area Flow Meters. In variable-head flow meters, the pressure differential varies with flow rate across a constant restriction. In variable-area meters, the differential is maintained constant and the restriction area allowed to change in proportion to the flow rate. A variable-area meter is thus essentially a form of variable orifice. In its most common form, a variable-area meter consists of a tapered tube mounted vertically and containing a float that is free to move in the tube. When flow is introduced into the small diameter bottom end, the float rises to a point of dynamic equiHbrium at which the pressure differential across the float balances the weight of the float less its buoyancy. The shape and weight of the float, the relative diameters of tube and float, and the variation of the tube diameter with elevation all determine the performance characteristics of the meter for a specific set of fluid conditions. A ball float in a conical constant-taper glass tube is the most common design it is widely used in the measurement of low flow rates at essentially constant viscosity. The flow rate is normally deterrnined visually by float position relative to an etched scale on the side of the tube. Such a meter is simple and inexpensive but, with care in manufacture and caHbration, can provide rea dings accurate to within several percent of full-scale flow for either Hquid or gas. [Pg.61]

Thickness. The traditional definition of thermal conductivity as an intrinsic property of a material where conduction is the only mode of heat transmission is not appHcable to low density materials. Although radiation between parallel surfaces is independent of distance, the measurement of X where radiation is significant requires the introduction of an additional variable, thickness. The thickness effect is observed in materials of low density at ambient temperatures and in materials of higher density at elevated temperatures. It depends on the radiation permeance of the materials, which in turn is influenced by the absorption coefficient and the density. For a cellular plastic material having a density on the order of 10 kg/m, the difference between a 25 and 100 mm thick specimen ranges from 12—15%. This reduces to less than 4% for a density of 48 kg/m. References 23—27 discuss the issue of thickness in more detail. [Pg.334]

In reeent years, tire use of elevated temperatures has been reeognised as a potential variable in method development. Witlr inereased temperature, aqueous-organie mobile phases separations ean improve, viseosity deereases and diffusion inereases so baek pressures are redueed. At higher temperatures (usually with superheated water > 100 °C under modest pressures) water alone ean be used as the mobile phase and eair provide unique separation opportunities. The absenee of an organie solvent enables the use in HPLC of alternative deteetors sueh as FID or on-line LC-NMR using deuterium oxide as the eluent. [Pg.16]

FOC drives are capable of providing precise speed control and are used for applications calling for high performance and precision (e.g. machine tools, high-speed elevators, mine winders, rolling mills, etc.). These drives are capable of regulating a number of variables at the same instant such as speed, position, acceleration and torque. [Pg.108]

Model IV Regenerator and reactor at approximately equal elevation and pressure. Catalyst circulates through U-bends, controlled by pressure balance and variable dense-phase riser. [Pg.21]

Simple examples of diazoalkylideneamine-l,2,3-triazole equilibria have been demonstrated for a series of l,2,3-triazolo[l,5-a]pyrimidines by variable-temperature NMR [74JCS(CC)671]. Tautomers A, B, and C interconvert rapidly at elevated temperatures the energy barrier for these ring-opening-ring closure processes was found to be AG = 76 kJ mol (for = H, Me R = CONH2) (Scheme 111). [Pg.261]

Leptin has been shown to markedly reduce appetite and weight in the extremely rare individuals who lack leptin. In contrast, in the first clinical study of patients with polygenic obesity and elevated leptin levels, weight loss was variable and relatively small. This disappointing result may be explained by the leptin resistance consistently observed in obese humans and rodents. However, it cannot be excluded that a small... [Pg.211]

Electron-donating groups strongly activate sulfonylation at ortho or para positions, with para sulfonylation more favored due to less steric hindrance. Variables, such as highly reactive monomers, elevated reaction temperatures, and high... [Pg.331]


See other pages where Variable elevations is mentioned: [Pg.110]    [Pg.371]    [Pg.2]    [Pg.91]    [Pg.392]    [Pg.110]    [Pg.371]    [Pg.2]    [Pg.91]    [Pg.392]    [Pg.2913]    [Pg.331]    [Pg.99]    [Pg.2]    [Pg.59]    [Pg.133]    [Pg.113]    [Pg.213]    [Pg.196]    [Pg.20]    [Pg.530]    [Pg.120]    [Pg.362]    [Pg.906]    [Pg.292]    [Pg.121]    [Pg.134]    [Pg.146]    [Pg.308]    [Pg.561]    [Pg.300]    [Pg.1037]    [Pg.855]    [Pg.7]    [Pg.272]    [Pg.319]    [Pg.383]    [Pg.126]   
See also in sourсe #XX -- [ Pg.110 ]




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