Latent hydraulic

Bo = q/Gh] Q, where t is the period between successive events, U is the mean velocity of single-phase flow in the micro-channel, Jh is the hydraulic diameter of the channel, q is heat flux, m is mass flux, /zlg is the latent heat of vaporization). The dependence t on Bo can be approximated, with a standard deviation of 16%, by... 

Mineral additions may be broadly categorized as pozzolanic materials or latent hydraulic cements. Neither type reacts significantly with water at ordinary temperatures in the absence of other substances. Pozzolanic materials are high in Si02 and often also in AI2O3, and low in CaO they are sufficiently reactive that mixtures of them with water and CaO produce C-S-H at ordinary temperatures and thereby act as hydraulic cements. If they contain AI2O3, calcium aluminate or aluminate silicate hydrates are also formed. Because they are low in CaO, this component must be supplied in stoichiometric quantity. In a composite cement, it is provided by the Portland cement through decreased formation of CH and decreased Ca/Si... 

Composite cements may contain mineral additions other than, or as well as, ones with pozzolanic or latent hydraulic properties. Regourd (R34) reviewed the use of ground limestone, which is widely used in France in proportions of up to 27%. The limestones used consist substantially of calcite, with smaller proportions of quartz or amorphous silica and sometimes of dolomite. They must be low in clay minerals and organic matter because of the effects these have on water demand and setting, respectively. The XRD peaks of the calcite are somewhat broadened, indicating either small crystallite size or disorder or both IR spectra confirm the occurrence of disorder. 

Activation of the latent hydraulic properties of foundry sand can also be achieved with gypsum (sulfate activation). Mixtures of foundry sand with a high aluminum oxide and lime content with ca. 15% calcium sulfate (as raw gypsum or natural anhydrite) are known as supersulfated cement. 

Uses Synthetic flavor and fragrance In foods and pharmaceuticals fragrance In cosmetics organic synthesis latent solvent Intermediate solvent for paints, lacquers, paint removers, cleaners, hydraulic fluids, pharmaceuticals fluorometric determinations llq. chromatography mfg. of Isobutyl esters for use In solvents, plasticizers, flavors, and perfumes extraction agent for phosphoric acid purification In food-pkg. adhesives defoamer In food-contact coatings and paper/paperboard In food-contact textiles Features Fruity flavor... 

Latently hydraulic materials are also able to react hydraulically, but only in the... 

Binders that contain latently hydraulic or pozzolanic or non-reactive constituents in combination with Portland clinker (and usually also with calcium sulfate) are called composite or blended cements. 

Latent hydraulic materials are also able to react hydrauhcally, but only in the presence of at least small amounts of a snitable activator. They are usually glassy or amorphous, and contain CaO, Si02, and AI2O3 as their main oxide constituents. Granulated blast furnace slag is the most widely used latent hydrauhc material. 

Activator—a substance that has to be added in small amounts to a latently hydraulic material to make it hydrate. 

Latently hydraulic material—material which—if ground to a powder—reacts in the presence of small amonnts of a suitable activator at ambient or moderately elevated temperatnres with water, to yield a hydrate (or hydrates) causing setting and hardening. 

The design of a steam condensate collection system is a complex task. It cannot be approached just as a problem in hydraulics, because it is also a problem in vapor-liquid equilibrium and in the conversion of sensible heat to latent heat. Considering these three factors together requires quite complex calculations, for which I have had to rely on the use of a computer model. These same sorts of considerations apply to multicomponent hydrocarbon systems, such as propane-butane refrigeration loops, but then the calculation complexity increases by an order of magnitude. 

An SCA is an analysis technique for discovering unplanned modes of operations or latent conditions that cause unexplained problems, cause unwanted functions to occur, or inhibit a desired function without regard to component failure or cause unrepeatable or intermittent glitches or anomalies, in electrical and electronic hardware and software systems, and other systems that transfer energy such as hydraulic and pneumatic systems. 

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