International kilogram

Variations in the Force Due to Gravity. The mass of an object is the quantity of matter ia the object. It is a fundamental quantity that is fixed, and does not change with time, temperature, location, etc. The standard for mass is a platinum—iridium cylinder, called the International Kilogram, maintained at the International Bureau of Weights and Measures, ia Snvres, France. The mass of this cylinder is 1 kg by definition (9). AH national mass standards are traceable to this artifact standard. 

International Isocyanate Institute, 25 480 International Jamaica Agreement, 12 695 International kilogram, 26 239 International Lubricant Standardization and Approval Committee (ILSAC), 15 228-230... 

The standard of mass is the kilogram (kg), defined as the mass of the international kilogram, a platinum cylinder preserved at Sevres, France. 

Figure 1-1 Of the fundamental SI units in Table 1-1, only the kilogram is defined by an artifact, rather than by a reprodudble physical measurement. The international kilogram in France, made from a Pt-lr alloy in 1885, has been removed from its protective enclosure to be weighed against working copies only in 1890,1948, and 1992. Its mass could change from reaction with the atmosphere or from wear, so there is ongoing research to define a standard for mass based on measurements that should not change over time. [Bureau International des Folds et Mesures.]...

As an example, the base unit of measurement for mass is defined as the mass of the international kilogram prototype kg is used as symbol for the base imit kilogram. As symbol for the base quantity mass, the dimension M is used. 

Analytical chemists make a distinction between calibration and standardization. Calibration ensures that the equipment or instrument used to measure the signal is operating correctly by using a standard known to produce an exact signal. Balances, for example, are calibrated using a standard weight whose mass can be traced to the internationally accepted platinum-iridium prototype kilogram. 

Mass. The unit of mass is the kilogram and is the mass of a particular cylinder of Pt—Ir alloy which is preserved in France by the International Bureau of Weights and Measures. 

Drum Drying. The dmm or roHer dryers used for milk operate on the same principles as for other products. A thin layer or film of product is dried over an internally steam-heated dmm with steam pressures up to 620 kPa (90 psi) and 149°C. Approximately 1.2—1.3 kg of steam ate requited per kilogram of water evaporated. The dry film produced on the roHer is scraped from the surface, moved from the dryer by conveyor, and pulverized, sized, cooled, and put iato a container. 

Kilogram. The kilogram is the unit of mass it is equal to the mass of the international prototype of the kilogram. 

Feeco International, Inc. To convert pounds per ciihic foot to kilograms per ciihic meter, multiply hy 16 to convert tons per hour to megagrams per hour, multiply hy 0.907 to convert feet to centimeters, multiply hy 30.5 to convert inches to centimeters, multiply hy 2.54 and to convert horsepower to kilowatts, multiply hy 0.746. 

It is usual these days to express all physical quantities in the system of units referred to as the Systeme International, SI for short. The International Unions of Pure and Applied Physics, and of Pure and Applied Chemistry both recommend SI units. The units are based on the metre, kilogram, second and the ampere as the fundamental units of length, mass, time and electric current. (There are three other fundamental units in SI, the kelvin, mole and candela which are the units of thermodynamic temperature, amount of substance and luminous intensity, respectively.)... 

Current research on fuel cells is directed toward the replacement of the internal combustion engine. To do this, hydrogen must be stored in the vehicle and replenished from time to time at filling stations. Three kilograms of hydrogen should be enough to drive a small car 500 km (300 miles) between fill-ups. 

For scientific work the fundamental standard of mass is the international prototype kilogram, which is a mass of platinum-iridium alloy made in 1887 and deposited in the International Bureau of Weights and Measures near Paris. Authentic copies of the standard are kept by the appropriate responsible authorities in the various countries of the world these copies are employed for the comparison of secondary standards, which are used in the calibration of weights for scientific work. The unit of mass that is almost universally employed in laboratory work, however, is the gram, which may be defined as the one-thousandth part of the mass of the international prototype kilogram. 

The metre-kilogram-second (mks system and the Systeme International d Unites (SI)... 

In this expression consistent units must be used. In the SI system each of the terms in equation 2.1 is expressed in Joules per kilogram (J/kg). In other systems either heat units (e g. cal/g) or mechanical energy units (e.g. erg/g) may be used, dU is a small change in the internal energy which is a property of the system it is therefore a perfect differential. On the other hand, Sq and SW are small quantities of heat and work they are not properties of the system and their values depend on the manner in which the change is effected they are, therefore, not perfect differentials. For a reversible process, however, both Sq and SW can be expressed in terms of properties of the system. For convenience, reference will be made to systems of unit mass and the effects on the surroundings will be disregarded. 

International System (SI) in terms of which all other units are defined. Examples kilogram for mass meter for length second for time kelvin for temperature ampere for electric current, basic ion An ion that acts as a Bronsted base. 

Let s use the international metric system units for this calculation. In this system, the energy ( ) is given in joules (7). A Joule is the amount of work done that will produce the power of one watt continuously for one second. It is roughly the amount of energy required to lift one kilogram 10 centimeters. Mass (m) in the equation is in kilograms, and the speed of light (c) is in meters per second. 

SI Units—The International System of Units as defined by the General Conference of Weights and Measures in 1960. These units are generally based on the meter/kilogram/second units, with special quantities for radiation including the becquerel, gray, and sievert. 

The ICRU (1980), ICRP (1984), and NCRP (1985) now recommend that the rad, roentgen, curie, and rem be replaced by the SI units gray (Gy), Coulomb per kilogram (C/kg), Becquerel (Bq), and sievert (Sv), respectively. The relationship between the customary units and the international system of units (SI) for radiological quantities is shown in Table D-5. 

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