Measurement rounding

A = quantity in ml of potassium permanganate solution used by the test sample, B = quantity in ml of potassium permanganate solution used in the blank test, oxygen number = 80 x (A-B). Use the arithmetical mean of the two measurements, rounded to 0.1. 

The average of the two measurements, rounded up to the nearest 0.2°C for bituminous binders with a softening point up to 80°C or up to the 0.5°C for bituminous binders with a softening point >80°C, is defined as the softening temperature or softening point ( r b)-... 

For the repetitive inspections the required hydrotest can only be performed for a limited number of the small cylinders, and even then the drums have to be removed from the line and the cylinders will be supported in defined distances for the weight of the water and the pressurisation. For the new and long cylinders even this is impossible, because they loose due to the additional weight of the water and the over-pressurisation their roundness and balances. Therefore the law in the most countries within and outside of the EU accept as a replacement of the hydrotest an additional application of different NDT methods, which were often done by an ultrasonic measurement of the wall thickness of the cylindrical part and a MT of the flat covers. 

As a first step in the direction outlined here some manufacturers and BAM last year discussed the problems and the possible procedures of such a system of quality assurance. As a result of this meeting round robin tests for the harmonization of the measurements of film system parameters and a possible procedure of surveillance of the quality of film systems were proposed. Closely related to these the BAM offers to perform the classification of film systems. But as during the production of films variations of the properties of the different batches cannot be avoided, the results of measurements of films of a single batch will be restricted to this charge, while only the measurements and mean of several batches of a film type will give representative values of its properties. This fact is taken into account already in section 4 of the standard EN 584-1 which can be interpreted as a kind of continuous surveillance. In accordance with this standard a film system caimot be certified on the base of measurements of a single emulsion only. 

A first comprehensive round robin test described in 4.1 which is open to all interested parties will be followed periodically by round robin tests in a reduced extent to ensure the further harmonisation of measurement procedures. The check of measurering equipments and procedures is an inalienable requirement for the further steps for providing the users with constant film quality. Together with sample tests performed by BAM as indicated in section 4.2 and and the production control by the manufacturer it will be possible to survey the film systems whether they meet the requirements of one of the film classes of EN 584-1. 

In case of mixed systems the procedure must be varied and it would be restricted to the special film systems of interest, of course. Mixed systems would be used by inspection companies and industrial users who normally do not dispose of the equipment for measurements as mentioned above. In these cases instead of a round robin test only periodical measurements of the properties of these mixed film systems by an independent third party institution can be used for film classification and continuous surveillance. 

Round robin tests for the harmonization of the measurements of film system parameters according to EN 584-1... 

At the beginning of the supervision of films systems first of all the influences of the exposure-and processing installations of the project partners on the determination of the film system parameters shall be found out and subsequently the equipments for measurement shjdl be compared one with another. This round robin test comprises in detail ... 

Figure Bl.19.16. Schematic view of the force sensor for an AFM. The essential features are a tip, shown as a rounded cone, a spring, and some device to measure the deflection of the spring. (Taken from [74], figure 6.)...

One of the advantages of the Verlet integrator is that it is time reversible and symplectic[30, 31, 32]. Reversibility means that in the absence of numerical round off error, if the trajectory is run for many time steps, say nAt, and the velocities are then reversed, the trajectory will retrace its path and after nAt more time steps it will land back where it started. An integrator can be viewed as a mapping from one point in phase apace to another. If this mapping is applied to a measurable point set of states at on(> time, it will... 

Place 2 1 ml. (measured from a micro-burette) of nitro-benzene and 5 g. of granulated tin in a 150 ml. round-bottomed flask fitted with a small reflux water-condenser. (A large flask is employed because the mixture when subsequently boiled may bump violently.) Pour 10 ml. of cone. HCl down the condenser on this scale the reaction is not sufficiently vigorous to get out of control. Heat over a gauze for 15 minutes. Cool the flask and add a solution of 7 5 8- of NaOH in 10 ml. of water to redissolve the initial precipitate. Add about... 

Reduction of a nitro compound to a primary amine. In a 50 ml. round-bottomed or conical flask fitted with a reflux condenser, place 1 g. of the nitro compound and 2 g. of granulated tin. Measure out 10 ml. of concentrated hydrochloric acid and add it in three equal portions to the mixtiue shake thoroughly after each addition. When the vigorous reaction subsides, heat under reflux on a water bath until the nitro compound has completely reacted (20-30 minutes). Shake the reaction mixture from time to time if the nitro compound appears to be very insoluble, add 5 ml. of alcohol. Cool the reaction mixture, and add 20-40 per cent, sodium hydroxide solution imtil the precipitate of tin hydroxide dissolves. Extract the resulting amine from the cooled solution with ether, and remove the ether by distillation. Examine the residue with regard to its solubility in 5 per cent, hydrochloric acid and its reaction with acetyl chloride or benzene-sulphonyl chloride. 

Standard practice for Brinell testing is to measure the diameter of each indentation twice and average the measurement before entering the tables to determine HBN. The same averaging principle is appHed on nonflat (curved) surfaces which yield an ediptical, not a round, indentation. 

The sound absorption of materials is frequency dependent most materials absorb more or less sound at some frequencies than at others. Sound absorption is usually measured in laboratories in 18 one-third octave frequency bands with center frequencies ranging from 100 to 5000 H2, but it is common practice to pubflsh only the data for the six octave band center frequencies from 125 to 4000 H2. SuppHers of acoustical products frequently report the noise reduction coefficient (NRC) for their materials. The NRC is the arithmetic mean of the absorption coefficients in the 250, 500, 1000, and 2000 H2 bands, rounded to the nearest multiple of 0.05. 

Tables 4—6 Ust ASTM methods used for the characterization of PB and PMP. A number of specialized methods were developed for testing particular articles manufactured from polyolefins several of these determine the performance of PB and PMP film, including the measurement of the film s dart impact strength and tear strength. Dart impact strength is measured by dropping a heavy dart with a round tip on a stretched film. Tear resistance, which reflects the film s resistance to tear propagation, is measured with the Ehnendorf tear tester. Two values for the tear strength are usually reported, one in the machine dkection of the film and the other in the transverse dkection. Pipes manufactured from PB are tested by pressurizing them internally with water the time-to-burst failure is determined at various temperatures (46). The standard test method for haze and luminous transmittance (ASTM D1003) is used for the measurement of PMP optical characteristics.

Drape can be measured by placing a circular fabric specimen over a round table or pedestal and viewing from direcdy overhead. A drape coefficient is defined as the ratio of the area of the fabric s actual shadow to the area of the shadow if the fabric were rigid. Drape is closely related to stiffness the drape coefficient for a stiff fabric approaches a value of 1 a limp fabric has a drape coefficient near 0. The Cusick drape tester is an example of this type of measurement. Eor this method, the relative weights of paper rings representing tracings of the fabric s shadows are used to calculate drape coefficient. 

Roundwood equivalent is also sometimes used. It refers to the volume of logs or other round products required to produce a given quantity of lumber, plywood, wood pulp, and other wood products (2). Roundwood equivalents may be used ia assessiag the overall wood resource supply and demand or ia comparing wood products measured ia different units. 

The work index may be round experimentally from laboratoiy crushing and grinding tests or from commercial miU operations. Some rules of thumb for extrapolating the work index to conditions different from those measured are that for dry grinding the index must be increased by a factor of 1.34 over that measured in wet grinding for open-circuit operations another factor of 1.34 is required over that measured in closed circuit if the product size Xp is extrapolated below 70 [Lm, an additional correction factor is (10.3 + Xp)/l.l45X . Also for a jaw or gyratory crusher the work index may be estimated from... 

If the technical staff from the client company recognizes that a toller may be asked to perform new analyses and make operating decisions based upon the results, the client may help the toller develop the needed procedures and skills required to make these decisions. Typically a round robin laboratory qualification exercise will be performed. Samples of known standards and unknown concentrations of the materials to be analyzed for the toll will be prepared and sent to both laboratories. This can help ensure that equipment calibration is synchronized and that the toller is capable of performing accurate measurements. In some cases, the toller may be the party with the chemical, process, or synthesis specific expertise. 

The phenomenon uneven distribution of current within the same conductor due to the inductive effect is known as the skin effect and results in an increased effective resistance of the conductor. The ratio of a.c. to d.c. resistance, R JR. is the measure of the skin effect and is known as the skin effect ratio . Figure 28.13(a) illustrates the skin elTect for various types and sizes of aluminium in flat sections. For easy reference, the skin effects in isolated round (solid or hollow) and channel conductors (in box form) are also shown in Figures 28.13(b) and (c) respectively. 

A better way of measuring is to measure the natural frequency of vibration of a round rod of the material, simply supported at its ends (Fig. 3.4) and heavily loaded by... 

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