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Testing conduct

Tests conducted on motors to verify the harmlessness and effectiveness of additives. [Pg.244]

This rule is justified by the need to limit the benzene emissions from evaporation (Tims, 1983) Figure 5.25 shows that emissions increase linearly with the benzene content of the fuel. It is noteworthy that current legislation limits the measured evaporation to 2 g per test conducted in accordance with a standard procedure (Sealed Housing for Evaporative Determination, or SHED). Yet for a fuel containing 5% benzene, an evaporation of 0.7 g benzene /test is observed. [Pg.258]

A specification or standard for product characteristics is valid only if it is matched with references to well defined and recognized test methods, such that quality control tests conducted by the parties involved —client and supplier, for example— are comparable even if they are performed at different locations. [Pg.445]

The radiation and temperature dependent mechanical properties of viscoelastic materials (modulus and loss) are of great interest throughout the plastics, polymer, and rubber from initial design to routine production. There are a number of laboratory research instruments are available to determine these properties. All these hardness tests conducted on polymeric materials involve the penetration of the sample under consideration by loaded spheres or other geometric shapes [1]. Most of these tests are to some extent arbitrary because the penetration of an indenter into viscoelastic material increases with time. For example, standard durometer test (the "Shore A") is widely used to measure the static "hardness" or resistance to indentation. However, it does not measure basic material properties, and its results depend on the specimen geometry (it is difficult to make available the identity of the initial position of the devices on cylinder or spherical surfaces while measuring) and test conditions, and some arbitrary time must be selected to compare different materials. [Pg.239]

A listing of compounds evaluated in the laboratory as cockroach repeUents summarizes 872 synthetic compounds out of 901 bioassayed from 1953 to 1974 (43). EenchoHc acid [512-77-6] (3-isopropyl-1-methylcyclopentanecarboxyHc acid) has been used as a standard repeUent in tests conducted by placing 20 cockroaches in a glass crystallizing dish without food and water and offering them a choice of two cardboard shelters, one of which was treated with 1 or 2 mL of a 1% solution of the candidate in acetone. Counts were made daily for seven days. [Pg.118]

Higher temperatures result in permanent degradation. The amount of this irreversible loss in mechanical properties depends upon moisture content, heating medium, temperature, exposure period, and, to some extent, species. The effects of these factors on modulus of mpture, modulus of elasticity, and work to maximum load are illustrated in Figures 6—9 (6). The effects may be less severe for commercial lumber than for clear wood heated in air (Fig. 10). The permanent property losses shown are based on tests conducted after specimens were cooled to - 24° C and conditioned to a moisture content of... [Pg.325]

This boron- and carbon-doped SiC exhibits excellent strength and stiffness, extreme hardness, and thermal and chemical resistance. The strength of this system is not affected by temperatures up to I650°C. Creep is virtually nonexistent up to I400°C. CycHc durabiUty testing conducted at I370°C in air showed no deterioration of strength after 3500 h (94). [Pg.466]

As commercially pure materials, the ethyleneamines exhibit good temperature stabiUty, but at elevated temperatures noticeable product breakdown may result in the formation of ammonia and lower and higher mol wt species. This degradation becomes mote pronounced at higher temperature and over longer time periods. Certain contaminants, such as mineral acids, can lower the onset temperature for rapid thermal decomposition. The manufacturer should be contacted and thermal stabiUty testing conducted whenever ethyleneamines ate mixed with other materials. [Pg.46]

Ethylene oxide has been shown to produce mutagenic and cytogenic effects in a variety of test systems (226). An increased frequency of chromosomal aberrations in peripheral lymphocytes of monkey exposed to ethylene oxide for 104 weeks has been reported (240). In mice, it is an effective inducer of chromosome breaks leading to dominant-lethal mutations. In addition, ethylene oxide has been shown to induce heritable effects in the heritable translocation test conducted in mice exposed to ethylene oxide by inhalation (241,242). In this study, male mice were exposed to ethylene oxide ranging from 165 to 300 ppm for 6 h per day 5 or 7 days/week for 8.5 weeks. Ethylene oxide has also been shown to bind to proteins (243) as well as to DNA (244). Several studies on ethylene oxide-exposed workers have demonstrated an increased incidence of chromosomal aberrations and sister chromatid exchanges the relevance of such effects to human health evaluation is currendy uncertain. [Pg.464]

Historically, the destmction efficiency for chlorinated hydrocarbons is quite low. In addition, tests conducted after the chlorinated hydrocarbon is treated show that the catalyst is partially deactivated. More recent advancements in catalyst technology have resulted in the development of a number of catalysts and catalytic systems capable of handling most chlorinated hydrocarbons under a variety of conditions (19). [Pg.505]

FIG. 26-30 Siipp ression of explosions, Pressures in an ethylene explosion and a sodium bicarbonate suppressed ethylene explosion, Tests conducted by Fike Corp, in a 1-m vessel. Ethylene concentration = 1,2 times stoichiometric concentration for combustion, (dp/dt)e = 169 bar/s (2451 psi/s), = reduced explosion pressure = 0,4 bar gauge (5,8 psig), (F/om Chatrathi, Explosion Testing, Safety and Technology News, vol. 3, issue 1, Pike Cotp., 1.98.9, hy permission. )... [Pg.2318]

ASTM G59, Standard Prac tice for Conducting Potentiodynamic Polarization Resistance Measurements, provides instructions for the graphical plotting of data (from tests conducted using the above-noted ASTM Standard G103) as the hnear potential versus current density, from which the polarization resistance can be found. [Pg.2441]

Tests conducted to operate centrifugal pumps as hydrauhc turbines throughout the head-capacity-speed range show that a good centrifugal pump generally makes an efficient hydraulic turbine. From theoretical considerations it is possible to state that at the same speed... [Pg.2525]

Preventive maintenance Inspection or testing conducted on equipment to detect impending or minor failures and restore the equipment to its proper condition. [Pg.215]

The declared efficiency and power factor of a motor are affected by its loading. Irrespective of the load, no-load losses as well as the reactive component of the motor remain constant. The useful stator current, i.e. the phase current minus the no-load current of a normal induction motor, has a power factor as high as 0.9-0.95. But because of the magnetizing current, the p.f. of the motor does not generally exceed 0.8-0.85 at full load. Thus, at loads lower than rated, the magnetizing current remaining the same, the power factor of the motor decreases sharply. The efficiency, however, remains practically constant for up to nearly 70% of load in view of the fact that maximum efficiency occurs at a load when copper losses (f R) are equal to the no-load losses. Table 1.9 shows an approximate variation in the power factor and efficiency with the load. From the various tests conducted on different types and sizes of motors, it has been established that the... [Pg.17]

This is the duration sufficient to simulate seismic conditions. It depends upon the algorithm used to find time history from the reqtiired response spectrum (RRS). The minimum duration of a strong movement, as recommended by IEEE 344, is 15 seconds as illustrated in Figure 14.24(b). This will require a total duration of the order of 20 seconds, including the movement s times of rise and time of decay. A duration of 20.48 seconds, as noted in the figure, is typical of a test conducted at University of Rorkee. The following tests may be conducted ... [Pg.448]

This is another name for a heat run test. A voltage sufficient to cause an output of the capacitor unit equal to 1.5 times the rated output is applied at the rated frequency and test conducted for at least 48 hours. During the last six hours of the test the temperature rise and tan 5 are measured at least four times. The temperature rise during the last six hours should not exceed 1 C, otherwise the test duration must be extended until the temperature stabilizes to a rise of only l°C. The final test results... [Pg.839]

Delta-connected units Test voltage 2V. Any two terminals of the unit should be shorted and the test conducted between the third and the shorted terminal. [Pg.840]

Tests conducted by the Eastman Kodak Company have shown that tert-butyl azidoformate [Formic acid, azido, -butyl ester], also known as iert-butoxy carbonyl azide and 1-BOC azide, is a thermally unstable, shock-sensitive compound (TNT equivalence 45%). [Pg.122]

Turbomachines can be compared with each other by dimensional analysis. This analysis produces various types of geometrically similar parameters. Dimensional analysis is a procedure where variables representing a physical situation are reduced into groups, which are dimensionless. These dimensionless groups can then be used to compare performance of various types of machines with each other. Dimensional analysis as used in turbomachines can be employed to (1) compare data from various types of machines—it is a useful technique in the development of blade passages and blade profiles, (2) select various types of units based on maximum efficiency and pressure head required, and (3) predict a prototype s performance from tests conducted on a smaller scale model or at lower speeds. [Pg.125]

As a part of the lubrication program, oil should be periodically tested. The testing requires drawing oil from the system for a laboratory analysis. The usual tests conducted to determine the condition of oils include viscosity, pH and neutralization number, precipitation, color and odor, and a check for foreign particles in the oil. The results should be reviewed and compared with new oil characteristics to determine the life characteristics of the oil. [Pg.556]

Tests conducted while the tower is upset can be relied upon only as a general indication of a problem. The data should be suspect and care should be used in its use. If at all possible, reduce rates in an attempt to eliminate the problem, then work up to higher rates. [Pg.298]

Adhesion of copper films to PMDA/ODA polyimide was determined by peel tests conducted on samples that were prepared by vapor-depositing a thin layer of copper onto the polyimide and then building the thickness of the metal layer to about 18 p,m by electrodeposition of copper. Results of the adhesion measurements correlated well with substrate pretreatment. When the substrate... [Pg.277]

This knowledge is also important in order to determine if air tests conducted by OSHA compliance officers are valid. For example, if threshold limit value in the health standard is an 8-hour time-weighted average, the air sample should be obtained by sampling over the entire shift in the employee s breathing zone. It cannot be measured by a few short term samples, even if spaced over the full shift unless the worker is in a relatively fixed location with no variation in his work procedure or in the process. Such an event is generally the exception rather than the rule. [Pg.261]

A different variety of copolymer has been prepared by Gramain and Frere who treated 1,10-diaza-l 8-crown-6 with the bisglycidyl ether of bisphenol A. The reaction was conducted at reflux in a mixture of THF and methanol. The polymer, illustrated in Eq. (6.24) was formed 83% yield. The polymer was appparently quite stable, surviving aging tests conducted over a two-year period. [Pg.278]


See other pages where Testing conduct is mentioned: [Pg.1064]    [Pg.437]    [Pg.491]    [Pg.200]    [Pg.45]    [Pg.188]    [Pg.272]    [Pg.369]    [Pg.432]    [Pg.172]    [Pg.458]    [Pg.474]    [Pg.505]    [Pg.199]    [Pg.290]    [Pg.557]    [Pg.136]    [Pg.488]    [Pg.2426]    [Pg.533]    [Pg.149]    [Pg.149]    [Pg.169]    [Pg.597]    [Pg.63]    [Pg.21]   
See also in sourсe #XX -- [ Pg.564 , Pg.565 ]




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Aqueous solution conductivity testing

Aqueous-extract conductivity test

Conducting polymer-based tests

Conducting your test

Conductivity testing

Criteria for the conduct of proficiency testing

Four-probe conductivity test

Hydraulic conductivity field testing

Hydraulic conductivity laboratory tests

Impact-Friction Pendulum Test as conducted

Impact-Friction Pendulum Test as conducted City, Mo A354 (Note

Impact-Friction Pendulum Test as conducted at the Spencer Chemical Co, Kansas

Test method thermal conductivity

Water testing conductivity

Wax-Gap Test as conducted at the Spencer

Wax-Gap Test as conducted at the Spencer Chemical Co, Kansas City

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