Small motor firings

Although the program was primarily concerned with the synthesis and laboratory evaluation of these new propellant compositions, some practical confirmation of their theoretical performance was also desired. Consequently, a limited number of small motor firings were carried out. 

The temperature coefficient of motor chamber pressure, irK, has been reported (17) to be about 0.09%/°F. in the static firing of small motors loaded with 2-in. diameter tubular grains (inside-outside burning). Measured specific impulse was reported to be 90% of theoretical. Higher percentages of theoretical specific impulse are obtained in larger motors. 

For the actual compositions tested, the theoretical values were somewhat lower than optimum. In all, 18 acetylenic polyurethane propellant grains were test fired in small motors. These ranged in weight from 0.40 to 6 lb. and included both 3-inch and 6-inch diameter end-burning grains. Motor firings are reported in Table III for a 77.8% oxidizer-loaded composition having a theoretical hp of 249 seconds. These can be compared... 

The last unit in our design problem is the drive belt. If the cutter were electrically driven by a constant speed motor, the major function of the belt would be the uniform transmission of power to the cam and, subsequently, to the cutter head. In this design, the cutter is driven by a gasoline motor which has pulsations in power output particularly a small motor of the type used in hand held units. The amount of flywheel effect that can be built into such a unit is limited and the pulsations caused by the individual firings in the motor cylinders is transmitted to the output shaft. 

Exposure to toxic fire effluents can lead to a combination of physiological and behavioral effects of which physical incapacitation, loss of motor coordination, disorientation are only a few. Furthermore, survivors of a fire may experience postexposure effects, complications, and burn injuries, leading to death or long-term impairment. The major effects, such as incapacitation or death, may be predicted using existing rat lethality data, as described in ISO 1334431 or more recently, based on the best available estimates of human toxicity thresholds as described in ISO 13571,5 by quantifying the fire effluents in different fire conditions in small-scale tests, using only chemical analysis, without animal exposure. 

Photographic reducer and developer reagent for the determination of small quantities of phosphate, dye intermediate stabilizer in paints and varnishes motor fuels and oils antioxidant for fats and oils, and a polymerization inhibitor. Therapeutically used topically for depigmentation to treat skin blemishes, for example, hypermelanosis. Hydroquinone occurs naturally, as a conjugate with jS-o-glucopyranoside, in the leaves, bark, and fruit of a number of plants, and its presence may be an important factor in fire-blight resistance in the pear. It may also play an important part in the defense mechanisms of some insects. 

Slag barrel spilled causing a small fire. Repairs to Slag conveyor motor and electrical controls. 

The torque produced by the motor is therefore reduced in proportion to the square of the rms value of the applied voltage. Circuits are available for both star and delta connected motors. Closed loop feedback control may be used to adjust the firing of the thyristors, thereby making accurate speed regulation possible. These systems are only used for small machines, e.g. up to 20 kW because they tend to produce many harmonic currents and voltages in the supply. 

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