Dials

Dirac showed in 1928 dial a fourth quantum number associated with intrinsic angidar momentum appears in a relativistic treatment of the free electron, it is customary to treat spin heiiristically. In general, the wavefimction of an electron is written as the product of the usual spatial part (which corresponds to a solution of the non-relativistic Sclnodinger equation and involves oidy the Cartesian coordinates of the particle) and a spin part a, where a is either a or p. A connnon shorthand notation is often used, whereby... 

Fig. 7.15 The variation in torsion angles can be effectively represented as a series of dials, where the time corresponds to the distance from the centre of the dial. Data from a molecular dynamics simulation of an intermolecular complex between the enzyme dihydrofolate reductase and a triazine inhibitor [Leach and Klein 1995].

Zinc sulfide is used in making luminous dials. X-ray and TV screens, and fluorescent lights. 

Amiao2 Oiethyl-l,3-prQpaDe-dial [4-d],- 2-AiBiiK>-2 chyl-1.3-propaoediol (Ij... 

The e ending of an alkane name is dropped before a suffix beginning with a vowel ( a/) and retained before one beginning with a consonant ( dial)... 

Aldehydes. When the group —C(=0)H, usually written —CHO, is attached to carbon at one (or both) end(s) of a linear acyclic chain the name is formed by adding the suffix -al (or -dial) to the name of the hydrocarbon containing the same number of carbon atoms. Examples are butanal for CHjCHjCHjCHO and propanedial for, OHCCH CHO. 

When using the DIAL method to measure the concentration of a molecule with discrete absorption the wavelengths of the two laser beams, on and off a narrow absorption line, must be very similar (less than 1 nm separation) so that the background absorption and backscatter is the same for both. 

Measurements of ozone concentration in the ozone layer in the stratosphere are made in the less intense Huggins band to avoid complete absorption of the laser radiation. Again, the two or three wavelength DIAL method is used to make allowance for background aerosol scattering. A suitable laser for these measurements is the XeCl pulsed excimer laser (see Section 9.2.8) with a wavelength of 308 nm, close to the peak absorption of the Huggins... 

Figure 9.35 Illustration of the two or three wavelength DIAL technique...

Diagem Diagnostics Diaion Diaion ITP Diaion ITP-20SS Dial... 

Rockwell. The invention of the Rockwed hardness tester in 1919 was an advance over previous indentation tests requiring accurate indentation measurement and tabular reduction to derive a hardness number. In the Rockwed test the hardness number is read direcdy from the instmment dial (1,3). 

The Rockwed testing machine is thus a framework permitting stable support of the workpiece on one side and means to impress the indenter under specified load on the other. A dial indicator attached to the indenter spindle is used to read directly the depth of indentation in hardness numbers. 

Most laboratory and shop-use Rockwell hardness testers are nonportable, lever operated, deadweight machines. Newer versions have digital readouts rather than the traditional analogue dial. Some designs of Rockwell testers employ a spring-loading system instead of deadweights. 

Barcol Indenter. The Barcol hardness tester is a hand-held, spring-loaded instmment with a steel indenter developed for use on hard plastics and soft metals (ASTM D2583) (2). In use the indenter is forced into the sample surface and a hardness number is read direcdy off the integral dial indicator caUbrated on a 0 to 100 scale. Barcol hardness numbers do not relate to nor can they be converted to other hardness scales. The Barcol instmment is caUbrated at each use by indenting an aluminum ahoy standard disk suppHed with it. The Barcol test is relatively insensitive to surface condition but may be affected by test sample size and thickness. 

Armour-Dial Consumer Renu2it aerosol, soHd, electric... 

Solvent system CMC concentration, g/350 cm Minimum viscometer dial reading at 600 rpm Maximum filtrate volume, 3 cm... 

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