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Setting times speed

The variable ERRORmj n represents the error in the position of the mandrel over an increment in TIME, in seconds. ERRORman is calculated by subtracting the actual pulses accumulated, PULSEman, from the desired number of pulses that would be generated under perfect control. The desired number of pulses for perfect control is determined by the set point speed, RPSman, revolutions per second and the mechanical gear reduction. The constant 15630 is the product of encoder counts per revolution and the thirty to one gear reduction of the mandrel. [Pg.541]

Crisp and coworkers found that the development of surface crystallinity was related to the speed of set. The faster the reaction, the shorter was the inhibition period before surface crystallization took place. When the setting time of a cement was between two and three minutes, surface crystallinity developed in a few minutes. When it was seven minutes, surface crystallinity was delayed by three hours. The reaction rate was affected by the chemical composition and physical state of the cement components. Well-ignited zinc oxide, the presence of magnesium in the... [Pg.210]

Setting times and hydrolytic stability of these cements are given in Table 8.3. In some cases the speed of reaction was very high, and practical cements could not be formed from ZnO or CaO even when these oxides were deactivated by heating. All the faster-setting cements exhibited good hydrolytic stability. The stability of the complexes between divalent cations and PVPA was found by a titrametric procedure to follow the order Mg Ca < Cu Zn (Ellis Wilson, 1991). This result was... [Pg.311]

The test piece is compressed at 23 °C and then held at the test temperature for a set time, commonly 24 h. For elevated temperatures the test piece is either immediately removed and allowed to recover at 23 °C for 30 min before measurement or allowed to cool whilst still compressed and measured after a further 30 min recovery. The first procedure has been standard for many years but is not a particularly logical sequence as it allows recovery at an undefined cooling rate, which must differ between the two sizes of test piece. A third alternative, not included, is to allow recovery at the test temperature. Recovery is speeded up at an elevated temperature and slowed down if cooling takes place under compression. [Pg.213]

Standard default settings v 2 times speed-up 3 times speed-up 7-8 times speed-up v library screening settings... [Pg.76]

The rapid diffusibUity of NO has critically important imphcations for its chemistry in the biological setting. The speed with which NO moves by random diffusion can be illustrated by consideration of its root mean square distance of displacement, which describes the distance a single NO molecule will move in any time interval based on its diffusion constant D (which is similar for aqueous solution and also tissue (brain) ) ... [Pg.2995]

A chute at an angle is mounted on a vertical shaft, which rotates to periodically move the chute through the stream of powder for a set time. By increasing the speed of rotation, an increase in the number of increments is taken, but this does not alter sample size. [Pg.2965]

Cup flow BS2782-86 Method 720 B Slow-curing thermosets Measure time to fill Set closing speed, force, amount of flash and temperature... [Pg.337]

Surface area is important in all applications where the process is surface-dependent like in mass and heat transfer, flow through packed beds or fluidization. Activity of drugs, setting time of cement and effectiveness of cracking catalysts are just three examples of direct dependence on specific surface. Some such materials, like fillers or catalysts, are often specified in units of specific surface rather than in particle size and its distribution. Specific surface also offers some practical advantages, in favourable cases, in the ease and speed of measurement and also in that it gives a... [Pg.23]

Figure A2.4 Comparison of the CPU time speed-up with the number of processors for three different basis sets of benchmark calculations on crambin (by courtesy of I. J. Figure A2.4 Comparison of the CPU time speed-up with the number of processors for three different basis sets of benchmark calculations on crambin (by courtesy of I. J.
Accessories which vendor should include in scope of supply for the DG Set Engine speed/generator tachometer, engine temperature, fuel oil tank level, lubrication pump pressure, kilowatts, voltage, ammeter, kilowatt-hour meter, frequency meter, engine running time totaliser, start-up batteries and battery charger. [Pg.190]

The setting times (initial and final set) are determined with Vicat s needle apparatus on a neat cement paste The cement is passed through a 1 mm test sieve and a quantity of 500g is mixed with 25—30% (by weight) of water - depending on the type of cement concerned - in a standard two-speed mixer for a total of... [Pg.94]

The CD model depends on the period Tcd (or, equivalently, on the frequency, CO ), its only adjustable parameter. This sets the speed of mixing. Through somewhat tedious calculations, it can be shown that the segregation index decreases exponentially with time. By introducing the nth order moments of the PDF ... [Pg.238]


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See also in sourсe #XX -- [ Pg.8 ]




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