NATIONAL BUREAU OF STANDARDS REPORT

8098

STANDARDIZATION OF THERMAL EMITTANCE MEASUREMENTS

PROGRESS REPORT No. 19

April 1 - June 30, 1963

Contract No. DO (33-616)61-02

Task No. 73603

AERONAUTICAL SYSTEMS DIVISION

AIR FORCE SYSTEMS COMMAND

UNITED STATES AIR FORCE

WRIGHT-PATTERSON AIR FORCE BASE, OHIO

U. S. DEPARTMENT OF COMMERCE

NATIONAL BUREAU OF STANDARDS
THE NATIONAL BUREAU OF STANDARDS

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Printing Office, Washington, D.C., 20402.
NATIONAL BUREAU OF STANDARDS REPORT

NBS PROJECT NBS REPORT

1009-11-10491 8098

STANDARDIZATION OF THERMAL EMITTANCE MEASUREMENTS

PROGRESS REPORT No. 19

April 1 - June 30, 1963

Contract No. DO 33(616)61-02

Task No. 73603

to

AERONAUTICAL SYSTEMS DIVISION

AIR FORCE SYSTEMS COMMAND

UNITED STATES AIR FORCE

WRIGHT -PATTERSON AIR FORCE BASE, OHIO

IMPORTANT NOTICE NATIONAL BUREAU OF S’

for use within the Government, and review. For this reason, tt whole or in part, is not autha Bureau of Standards, Washingi

the Report has been specificall)

Approved for public release by the

Director of the National Institute of

Standards and Technology (NIST) on October 9, 2015.

jss accounting documents intended

i subjected to additional evaluation

5 listing of this Report, either in

le Office of the Director, National

1 the Government agency for which

copies for its own use.

U. S. DEPARTMENT OF COMMERCE

NATIONAL BUREAU OF STANDARDS

NOTICES

When Government drawings, specifications, or other data are used

for any purpose other than in connection with a definitely related

Government procurement operation, the United States Government thereby

incurs no responsibility nor any obligation whatsoever; and the fact

that the Government may have formulated, furnished, or in any way supplied the said drawings, specifications, or other data, is not to be

regarded by implication or otherwise as in any manner licensing the

holder or any other person or corporation, or conveying any rights or permission to manufacture, use, or sell any patented invention that

may in any way be related thereto.

This document may not be reproduced or published in any form in

whole or in part without prior approval of the Government. Since this

is a progress report, the information herein is tentative and subject

to changes, corrections, and modifications.

I. SUMMARY

Some progress has been made toward calibrating the wavelength drum

settings with the cesium bromide prism in the wavelength range of 15 to 40

microns. The 0.484-inch diameter working standards of platinum- 13% rhodium

alloy and oxidized sandblasted Inconel were calibrated over the wavelength

range of 1 to 15 microns, and transmitted to A.S.D.

II. INSTRUMENTATION

Air Purification System

Most of the components for the air purification system mentioned in

the report for January 1 through March 31, 1963, were received during this

report period, and installation was about 90% complete at the end of the

period

Filter Circuits

The filter circuits referred to in the preceding report were received

and installed.

Long-Wavelength Accessories

Preliminary tests of the spectrometer with the cesium bromide prism

and the Nernst glower source, indicated that scattered radiation is a problem at wavelengths beyond about 25 microns. Most of the scattering that causes trouble is believed to occur at wavelengths below 15 microns, and

much of it is in the visible portion of the spectrum. A special AgCl disc

filter, designed to pass the long-wavelength radiation up to 28[i and block

the short-wavelength radiation below 4.5p, a special CaF reststrahlen plate,

designed to scatter the short-wavelength radiation and to specularly re- flect the long-wavelength radiation from 1 5-40|_i, and a black polyethylene

film, which transmits only beyond 28p, were ordered for use with the equipment. The manufacturer states that use of these accessories should markedly reduce interference from scattered radiation within the monochromator.

III. DATA -PROCESSING ATTACHMENT

The data-processing attachment is now performing a substantial portion

of the operations it was designed to perform. The analog- to-digital con- verters on the wavelength drum shaft and the recording potentiometer operate satisfactorily. The pulses from the converters are correctly counted

on the counters in the data-processing attachment, and the correct counts are displayed on the digital register. The counts are correctly punched on paper tape at the proper preselected wavelength-drum-dial increments. The

paper tape reader correctly reads the prepunched numbers from the tape, and,

when controlled by the prepunched paper tape, the data-processing attachment

accumulates the emittance values at the preselected wavelength intervals for

computation of total emittance by the 100-selected-ordinate method.
2

The remaining functional difficulty is that the attachment does not

properly correct for "zero line" and "100% line" errors. The correction

process was designed to comprise the following operations. (1) The pulses

produced by the a-d converter on the potentiometer recorder are recorded on magnetic tape during the 100%- line and zero- line calibration runs, respectively. (2) The magnetic tape is played back synchronously with the speci- men run, and the pulses previously recorded are read from the tape. (3)

The pulses from the magnetic tape are amplified. (4) The amplified pulses

are used, by means of a monostable multivibrator circuit and ratchet motor,

to drive the 100% or zero potentiometer up or down scale as required to

correct the measured emittance of the specimen, prior to its recording.

Tests have shown that the pulses are correctly recorded on the magnetic tape, and are correctly read from the tape. The ratchet motors also appear to be operating satisfactorily. The trouble appears to be due to malfunctioning of either the power amplifier or the gating in the multivibrator

circuits. The work of correcting the remaining difficulties in the correction circuits is continuing.

IV. CALIBRATION OF WORKING STANDARDS

Calibration of two types of 0.484- inch diameter disc working standards

was completed, and the standards were transmitted to A. S. D.

Platinum- 13% Rhodium Working Standards

The platinum-13% rhodium specimens were received from the fabricator in

the form of 0.035-inch sheet, cut into two strip specimens 1/4 x 8 in. in

size, and five discs 0.484 inch in diameter. The original sheet of alloy

from which the specimens were cut was approximately 1 1/16 x 8 in. in size.

The 1/4 x 8 inch strips were cut from the two edges of the original sheet, and

the discs were cut from the central portion of the remaining strip.

Each specimen was washed in hot tap water to which a commercial detergent

had been added, rinsed in running hot tap water, then in distilled water, and

finally in ethyl alcohol. Rubber surgical gloves were worn at all times while

handling the specimens, and they were touched only at the ends or edges after

cleaning. The specimens were dried in air and placed in a closed container,

supported by the ends or edges only, for storage prior to annealing .

All specimens were annealed in an electric furnace with silicon car- bide heating elements. The strip specimens were hung by means of platinum

hooks, suspended from aluminum oxide rods in the furnace; the disc speci- mens were supported by the edges only on ceramic forms resting on a rigid

ceramic slab. All of the specimens were then enclosed in a ceramic muffle.

Starting with ambient conditions, the temperature of the furnace was raised

to 1523°K (1250°C) over a period of six hours, and held at that temperature

for one hour. The power was then turned off, and the specimens were allowed to cool in the furnace, which required two days.
3

The specimens were removed from the furnace by means of cleaned, platinym tipped tongs and were placed in individual plastic holders, in which

they were supported by the ends or edges only. Each plastic holder, con- taining a specimen, was then placed in an individual cardboard box, to protect the specimen from contamination.

The two 1/4 x 8-inch strips were prepared for measurement by welding a platinum-platinum 10% rhodium thermocouple to each specimen. A shallow

groove was scratched in each specimen, normal to its axis and located at the

midlength. The 10-mil thermocouple wires were separately welded to the

specimen by means of a condenser-discharge type of electronic spot welder.

Each wire was laid in the shallow groove to position it for welding, and the

welding operation was observed through a low-power microscope.

Three sets of curves were made for each strip specimen at each of three

temperatures, 800°, 1100° and 1300°K. Each set of curves consisted of (1) a 100% curve, obtained when the two blackbody furnaces at the test temperature

served as sources for the respective beams, (2) a zero curve, obtained with

the specimen beam blocked near the specimen furnace, and (3) a specimen

curve, obtained with the comparison blackbody at the test temperature as source for the comparison beam, and the hot specimen at the same temperature

serving as source for the specimen beam. The height of each curve was re- corded on punched paper tape at each 0.1 revolution of the wavelength dial

over the range corresponding to approximately 1 to 15 microns.

The punched paper tape containing the raw emittance data was fed into

an IBM 7090 computer, which then corrected the recorded emittance of the

specimen at each wavelength on the basis of the recorded 100% and zero

curves

The corrected emittance values for the six measurements, three each on two specimens, were then fed back into the computer, and the following

values were computed at each of the approximately 110 wavelengths. (1), E,

the average emittance, (2) r^, the standard deviation—^ due to error of

measurement, computed as the average standard deviation of the three measurements on each specimen about the mean for that specimen, and (3) ct s , the

standard deviation due to differences in specimens.

1/ All standard deviations in this study are precisely defined as "estimates

of the standard deviation of the parent population from which the measurements were drawn." Mathematically

where x is an individual measurement, x , is the average of n measurements on specimen one, and p is the number of specimens. (For data in this report, n = 3 In all cases, and p = 2 for platinum- 13% alloy and 6 for oxidized sandblasted Inconel.)

where x is the overall average of the n x p measurements, n each on p specm

(n-l)p

linens
4

The values obtained on the platinum- 13% rhodium specimens are tabulated

in Table I, and are shown in figures 1 through 6.

The spectral emittance curves for the platinum-13% rhodium alloy, shown

in figure 1 at 800°K, figure 2 at 1100°K and figure 3 at 1300°K, are quite

similar to the corresponding curves for platinum.

The principal differences are that (1) in general, the emittance of the

platinum-13% rhodium alloy is higher than that of platinum at the same temperature and at the same wavelength, (2) the maximum at about 1.4 micron at

800°K is lower for the platinum-13% rhodium alloy than for platinum, (3) the

maximum at about 1.36 micron for platinum and 1100°K has moved to about 1.12

microns for platinum-13% rhodium and (4) no evidence of a maximum at 15 microns or beyond is seen in the platinum-13% rhodium data.

The standard deviations rrs and am

are plotted as a function of wavelength

in figure 4 at 800°K, figure 5 at 1100°K and figure 6 at 1300°K. In general

the am

values show less variation with wavelength than the as values. The

average values of crm

were 0.23 at 800°K, 0.19 at 1100°K and 0.33 at 1300°K,

and the corresponding values of crg were 0.25 at 800°K, 0.57 at 1100°K and

0.91 at 1300°K. However, the <rs values are based on only two specimens, and

hence are not highly reliable.

The increase in precision (lower CTm

values) over what was obtained in

the tests on platinum reported in WADC TR 59-510 Pt IV can be ascribed in

part to the reduction in error due to direct recording of data by the dataprocessing attachment as compared to reading the curves with a variable

scale.

Oxidized Inconel Working Standards

Specimens were cut from 2x8 inch Inconel sheet. Six strips, 1/4 x 8

inches in size were cut from the two edges of the sheet, three from each

edge. Twelve discs, 0.484-inch in diameter, were cut from the center of the

sheet. All specimens were marked for identification, and the position and

orientation of each specimen in the original sheet was recorded. The speci- mens were sandblasted with 60-mesh fused alumina grit and an air pressure of

approximately 70 psi, care being taken to obtain a uniformly rough surface

on all specimens. The sandblasted specimens were cleaned ultrasonically in

acetone, passivated for one minute in 10%, nitric acid at 316°K (43°C),

rinsed in distilled water and then in freshly distilled acetone. The cleaned

specimens were subjected to a minimum of handling. When handling was un- avoidable, rubber surgical gloves were worn, and the specimens were touched

only by the ends or edges

The strip specimens were suspended from a metal rack by means of oxidation-resistant metal hooks, and the rack was inserted into a cold furnace.

The disc specimens were supported by the edges only on special ceramic supports placed on the hearth of the furnace, and enclosed in a ceramic muffle.

The furnace was

Qbrought to 1340°K (1067°C) and held for 24 hours, then

dropped to 1100°K (827°C) and held for an additional 24 hours, after which

the specimens were allowed to cool in the furnace.
5

The specimens were removed from the furnace by means of cleaned stainless steel tongs, and were placed in individual plastic holders, in which

they were supported by the ends or edges only. Each plastic holder, con- taining a specimen, was then placed in an individual cardboard box, to protect the specimen against contamination.

The six 1/4 x 8 inch strips were prepared for measurement by welding a platinum-platinum 10% rhodium thermocouple to each specimen. The oxide

coating was removed in narrow strips and a shallow groove was scratched in

each specimen near its mid length and normal to its axis. The oxide was also removed by grinding for a distance of approximately one inch from each

end. The thermocouples were welded by a procedure similar to that used for

the platinum- 13% rhodium specimens.

The normal spectral emittance of each of the six specimens was measured

three times at each of three temperatures, and the data were analyzed statistically, as in the case of the platinum- 137, rhodium specimens. The re- sults are shown in Table II and are plotted as a function of wavelength in

figures 7 through 12.

The general shape of the spectral emittance curves is similar to that

obtained on the previous standards, but the emittance at each wavelength is

somewhat higher. There was a slight increase in emittance with an increase

in temperature at each wavelength.

2 / 2 / O

The values of and crs — obtained at 800 K are plotted in figure 10,

at 1100°K in figure 11 and at 1300°K in figure 12.

In general the values of crs were somewhat larger than those of rfa, and

showed greater variation with wavelength. The average values of rrm were

0.70 at 800°K, 0.59 at 1100°K and 0.63 at 1300°K and the corresponding values

of cts were 0.82 at 800 'K, 1.04 at 1100°K and 1.00 at 1300°K. This is a con- siderable improvement in reproducibility of specimens over what was obtained

in the tests reported in WADC TR 59-510 Pt IV, and is part due to the fact

that the specimens were cut from adjacent portions of the original sheet.

There is also some improvement in precision over the corresponding data

reported in WADC TR 59-510 Pt IV, which can again be ascribed to a reduction

in the reading error due to use of the data-processing attachment.

2/ See footnote 1 on page 3.
- 6 -

V. EQUATIONS RELATING SPECTRAL EMISSIVITY

OF METALS TO OTHER PROPERTIES

In this phase of the work, a study is being directed toward explaining

the irregularities and inflections observed in experimental emissivity

(reflectivity) data. The mechanism of this phenomenon is thought to be

characterized by contribution of several types of free and bound electrons.

As stated in the previous report, no set of parameters has yet been determined for the metal rhodium that will produce a normal spectral reflectivity

curve which fits the observed data over a wide wavelength interval

(0.1 to 10[i), both generally and in detail.

The computer program used in the process of determining the best values

of the parameters is being modified to calculate the optical constants.

These values will be compared with experimental data available from the

literature. This comparison should give an indicfation of the physical creditability of this approach.

To date a small fraction of the total effort in this project has been

devoted to this phase of the work. In the following quarter, efforts will

be intensified to determine whether this approach merits a continued or en- hanced use in achieving a better understanding of the principles governing

spectral variation in the emissivity of metals.
- 7

-

TABLE I

NORMAL SPECTRAL EMITTANCE OF

PLATINUM RHODIUM WORKING STANDARDS AT 800 °K

Wavelength Emittance^ 2/

(7m~~ 2/

Microns X100 X100 X100

1.18 24.2 .16 .19

1.25 25.5 .49 .26

1.33 26.1 .29 .94

1.40 26.2 .30 .90

1.48 25.2 .15 1.06

1.58 23.7 .23 .97

1.68 22.1 .30 .78

1.81 20.6 .18 .73

1.98 19.2 .24 .64

2.23 17.7 .36 .42

2.51 16.5 .34 .33

2.73 15.4 .29 .26

2.92 14.7 .29 .07

3.14 13.8 .38 .05

3.35 13.2 .27 .07

3.56 12.6 .20 .14

3.77 12.2 .20 .26

3.98 11.7 .16 .19

4.20 11.3 .15 .38

4.41 11.0 .33 .14

4.58 10.8 .26 .19

4.76 10.5 .27 .19

4.91 10.2 .23 .31

5.07 10.1 .23 .35

5.21 9.9 .20 .21

5.34 9.7 .27 .31

5.47 9.7 .17 .42

5.60 9.5 .22 .40

5.76 9.3 .22 .40

5.90 9.1 .09 .45

6.04 8.9 .15 .40

6.16 8.7 .20 .35

6.28 8.7 .15 .28

6.41 8.6 .16 .31

6.53 8.6 .21 .24
- 8 -

TABLE I cont ' d

NORMAL SPECTRAL EMITTANCE OF

PLATINUM RHODIUM WORKING STANDARDS AT

Wavelength _ . 1/ Emittance— 2/

Microns X100 X100

6.64 8.5 .33

6.76 8.4 .22

6.87 8.4 .16

6.97 8.4 .21

7.07 8.4 .20

7.19 8.3 .21

7.32 8.2 .18

7.44 8.2 .15

7.56 8.1 .19

7.66 8.0 .12

7.77 8.0 .20

7.88 7.9 .21

7.98 7.9 .15

8.08 7.9 .23

8.18 7.8 .23

8.28 7.8 .24

8.38 7.9 .24

8.47 8.0 .31

8.57 8.0 .22

8.66 8.0 .23

8.75 8.1 .22

8.84 8.1 .26

8.93 8.1 .17

9.01 8.0 .13

9.10 8.0 .18

9.18 8.1 .23

9.26 8.1 .24

9.35 8.6 .25

9.43 9.1 .25

9.51 9.4 .13

9.67 9.3 .16

9.83 8.6 .31

10.00 8.1 .14

10.15 7.8 .24

10.30 7.6 .24

800°K

2 /

gs~ X100

.31

.33

.38

.42

.28

.40

.47

.40

.45

.49

.33

.35

.35

.33

.26

.28

.33

.12

.19

.26

.14

.16

.24

.12

.19

.33

.16

.02

.02

.05

.26

.21

.19

.19

.19
9

TABLE I cont'd.

NORMAL SPECTRAL EMITTANCE OF

PLATINUM RHODIUM WORKING STANDARDS AT 800 °K

Wavelength J 1/ Emittance - 2/

°m— 2/

Microns X100 X100 X100

10.46 7.3 .23 .07

10.61 7.2 .31 .14

10.76 7.1 .15 .09

10.91 7.0 .34 .14

11.05 7.0 .29 .16

11.19 6.9 .23 .24

11.32 6.8 .25 .16

11.45 6.8 .18 .05

11.58 6.6 .30 .16

11.72 6.6 .14 .14

11.84 6.5 .19 .09

11.97 6.6 .24 .26

12.09 6.4 .39 .21

12.22 6.5 .20 .12

12.35 6.4 .22 .12

12.48 6.4 .24 .12

12.60 6.2 .18 .12

12.72 6.2 .16 .09

12.85 6.2 .20 .16

12.98 6.2 .17 .19

13.10 6.2 .18 .09

13.22 6.2 .23 .05

13.34 6.0 .30 .09

13.46 6.0 .23 .05

13.58 6.0 .19 .09

13.69 5.9 .23 .09

13.81 5.9 .28 .12

13.93 5.8 .17 .07

14.03 5.8 .32 .26

14.14 5.8 .30 .24

14.25 5.7 .26 .21

14.36 5.7 .27 .19

14.47 5.7 .22 .14

14.58 5.6 .41 .09

14.68 5.5 .31 .09
- 10

TABLE 1 cont'd.

NORMAL SPECTRAL EMITTANCE OF

PLATINUM RHODIUM WORKING STANDARDS AT 800 °K

Wavelength Emittance—

„ f<3m 2

<T S - Microns X100 X100 X100

14.79 5.6 .27 .02

14.90 5.6 .33 .07

15.01 5.7 .22 .02

15.11 5.6 .26 .07

1/ Average of 6 measured values, three each on two specimens

2/ See footnote 1 on page 3 in the text.
11

TABLE I cont'd.

NORMAL SPECTRAL EMITTANCE OF

PLATINUM RHODIUM WORKING STANDARDS AT 1100°K

1 / 2 / 2 /

Wavelength Emittancd- Microns X100 X100 X100

1.07 23.1 .45 .14

1.12 23.3 .47 .24

1.18 23.1 .48 .02

1.25 22.5 .56 .14

1.33 22.3 .50 .24

1.40 21.8 .39 .09

1.48 21.3 .37 .02

1.58 20.7 .37

1.68 20.0 .34 .02

1.81 19.1 .29 .07

1.98 18.5 .26 .16

2.23 17.7 .29 .21

2.51 16.8 .24 .16

2.73 16.1 .17 .14

2.92 15.7 .22 .38

3.14 15.0 .27 .54

3.35 14.6 .34 .61

3.56 14.2 .38 .61

3.77 13.9 .34 .94

3.98 13.5 .35 1.11

4.20 13.1 .23 1.06

4.41 12.7 .16 1.15

4.58 12.5 .16 1.11

4.76 12.2 .21 1.13

4.91 12.0 .21 1.13

5.07 11.8 .10 1.13

5.21 11.6 .14 1.23

5.34 11.4 .20 1.15

5.47 11.2 .18 1.18

5.60 11.0 .24 1.30

5.76 10.9 .13 1.15

5.90 10.7 .12 1.06

6.04 10.5 .18 .97

6.16 10.5 .13 .94

6.28 10.4 .13 .94
12

TABLE I cont'd.

NORMAL SPECTRAL EMITTANCE OF

PLATINUM RHODIUM WORKING STANDARDS AT 1100°K

1 / 2 / 2 /

Wavelength Emittance as Microns X 100 X100 xioo

6.41 10.3 .18 .99

6.53 10.1 .12 .75

6.64 10.0 .17 .80

6.76 9.8 .18 .78

6.87 9.8 .08 .94

6.97 9.6 .14 .94

7.07 9.6 .13 1.08

7.19 9.5 .22 1.04

7.32 9.5 .17 .99

7.44 9.4 .18 1.01

7.56 9.4 .20 1.01

7.66 9.3 .15 .97

7.77 9.2 .15 .94

7.88 9.2 .09 .92

7.98 9.1 .13 .94

8.08 9.0 .19 .90

8.18 9.1 .19 .90

8.28 9.1 .15 .80

8.38 9.0 .09 .82

8.47 9.1 .08 .90

8.57 9.2 .12 .78

8.66 9.2 .11 .87

8.75 9.3 .08 .75

S .84 9.2 .15 .73

8.93 9.2 .06 .73

9.01 9.3 .11 .68

9.10 9.3 .08 .61

9.18 9.2 .12 .64

9.26 9.2 .16 .66

9.35 9.3 .15 .68

9.43 9.7 .11 .73

9.51 10.0 .18 .52

9.67 10,2 .07 .42

9.83 9.8 .12 .31

10.00 9.4 .19 .31
13 -

TABLE I cont 1 d

.

NORMAL SPECTRAL EMITTANCE OF

PLATINUM RHODIUM WORKING STANDARDS AT 1100°K

Wavelength „ J 1/ Emittance— 2/ 2/

<7S Microns X100 X100 X100

10.15 9.0 .31 .35

10.30 8.6 .20 .28

10.46 8.4 .24 .54

10.61 8.4 .20 .52

10.76 8.2 .10 .42

10.91 8.1 .19 .40

11.05 8.0 .19 .38

11.19 7.8 .14 .38

11.32 7.8 .15 .54

11.45 7.7 .11 .61

11.58 7.6 .14 .54

11.72 7.5 .21 .45

11.84 7.4 .16 .33

11.97 7.4 .15 .47

12.09 7.3 .06 .40

12.22 7.3 .08 .38

12.35 7.2 .15 .42

12.48 7.2 .10 .49

12.60 7.2 .08 .38

12.72 7.1 .08 .26

12.85 7.0 .17 .26

12.98 7.0 .11 .24

13.10 6.9 .11 .38

13.22 6.9 .04 .16

13.34 6.9 .17 .21

13.46 6.9 .13 .19

13.58 6.8 .08 .05

13.69 6.8 .09 .14

13.81 6.7 .13 .16

13.93 6.8 .11 .26

14.03 6.6 .22 .19

14.14 6.6 .14 .21

14.25 6.5 .22 .05

14.36 6.5 .20 .31

14.47 6.4 .19 .19
14 -

TABLE I cont'd.

NORMAL SPECTRAL EMITTANCE OF

PLATINUM RHODIUM WORKING STANDARDS AT 1100°K

Wavelength „ , 1/Emittance

2/

®tn 2/

0S

Microns X100 X100 xioo

14.58 6.5 .16 .12

14.68 6.5 .22 .28

14.79 6,5 .17 .19

14.90 6.4 .14 .19

15.01 6.4 .25 .21

15.11 6.4 .37 .31

1 / Average of 6 measured values, three each on two specimens

2/ See footnote 1 on page 3 in the text.
15

TABLE I cont ' d

.

NORMAL SPECTRAL EMITTANCE OF

PLATINUM RHODIUM WORKING STANDARDS AT 1300

Wavelength

1/

Emittance 2/

Microns X100 X100

1.07 25.4 1.07

1.12 25.2 .94

1.18 24.7 .87

1.25 24.3 .68

1.33 23.7 .43

1.40 23.1 .40

1.48 22.6 .30

1.58 22.0 .29

1.68 21.2 .24

1.81 20.4 .43

1.98 19.7 .29

2.23 18.7 .39

2.51 18.0 .41

2.73 17.3 .32

2.92 16.6 .23

3.14 16.2 .21

3.35 15.9 .16

3.56 15.3 .15

3.77 15,0 .23

3.98 14.6 .26

4.20 14.4 .25

4.41 14.0 .23

4.58 13.8 .26

4.76 13.7 .31

4.91 13.3 .23

5.07 13.2 .26

5.21 12.9 .27

5.34 12.8 .18

5.47 12.7 .18

5.60 12.5 .19

5.76 12.3 .25

5.90 12.1 .21

6.04 11.9 .25

6.16 11.6 .29

6.28 xx.s .31

K

2 /

X100

.28

.14

.02

.12

.02

.02

.19

.28

.19

.38

.40

.57

.57

.59

.75

.97

.87

1.06

1.11

1.18

1.30

1.53

1.65

1.72

1.81

1.77

1.74

1.74

1.65

1.70

1.60

1.63

1.60

1.65
- 16 -

TABLE I cont ' d .

NORMAL SPECTRAL EM1TTANGE OF

PLATINUM RHODIUM WORKING STANDARDS AT 1300°K

Wavelength Emittance

2/ 2 Og

Microns X10Q X100 X100

6.41 11.6 .36 1.86

6.53 11.3 .38 1.67

6.64 11.2 .29 1.63

6.76 11.1 .38 1.65

6.87 11.0 .27 1.65

6.97 10.9 .22 1.65

7,07 10.8 .20 1.56

7.19 10.8 .15 1.46

7.32 10.7 .13 1.60

7.44 10.7 .22 1.56

7.56 10.6 .18 1.58

7.66 10.4 .28 1.63

7.77 10.4 .24 1.53

7.88 10.4 .13 1,53

7.98 10.4 .25 1.63

8.08 10.4 .27 1.60

8.18 10.3 .29 1.44

8.28 10.3 .19 1.39

8.38 10.2 .19 1.48

8.47 10.2 .20 1.46

8.57 10.2 .15 1.34

8.66 10.2 .17 1.37

8.75 10.2 .17 1.41

8.84 10.3 .19 1.32

g .93 10.2 .17 1.34

9.01 10.3 .18 1.34

9.10 10.2 .22 1.23

9.18 10.2 .15 1.18

9.26 10.2 .15 1.18

9.35 10.2 .16 1.30

9.43 10.2 .13 1.25

9.51 10.5 .10 1.20

9.67 10.9 ,12 1.06

9.83 IX. 0 .10 .99

10.0© 10.5 .12 1,06
17

TABLE I cont'd.

NORMAL SPECTRAL EMITTANCE OF

PLATINUM RHODIUM WORKING STANDARDS AT 1300°K

Wavelength Emittance —

2/ 2/

<7 S Microns X100 X100 xioo

10.15 10.0 .27 1.04

10.30 9.7 .20 .92

10.46 9.5 .33 1.04

10.61 9.2 .15 .97

10.76 9.1 .15 .97

10.91 9.0 .08 .75

11.05 8.9 .12 .78

11.19 8.8 .16 .85

11.32 8.7 .25 .80

11.45 8.5 .09 .85

11.58 8.5 .09 .73

11.72 8.4 .17 .71

11.84 8.3 .14 .66

11.97 8.2 .19 .59

12.09 8.0 .20 .68

12.22 8.1 .09 .57

12.35 8.0 .15 .57

12.48 7.9 .13 .47

12.60 7.8 .20 .45

12.72 7.8 .16 .21

12.85 7.7 .15 .24

12.98 7.6 .14 .28

13.10 7.5 .11 .19

13.22 7.5 .17 .26

13.34 7.5 .28 .33

13.46 7.4 .19 .05

13.58 7.3 .17 .21

13.69 7.2 .12 .16

13.81 7.3 .15 .02

13.93 7.3 .15 .16

14.03 7.2 .18 .16

14.14 7.2 .16 .02

14.25 7.2 .13 .05

14.36 7.1 .11 .02

14.47 7.2 .16
18 -

TABLE I cont'd.

NORMAL SPECTRAL EMITTANCE OF

PLATINUM RHODIUM WORKING STANDARDS AT 1300°K

Wavelength Emittance °m

Microns X100 X100 X100

14.58 7.0 .16 .09

14.68 7.2 .21 .07

14.79 7.1 .16 .05

14.90 7.0 .23 .07

15.01 7.2 .19

15.11 7.2 .18 .05

1/ Average of 6 measured values, three each on two specimens

2/ See footnote 1 on page 3 in the text.
19

TABLE II

NORMAL SPECTRAL EMITTANCE OF

OXIDIZED INCONEL WORKING STANDARDS AT 800°K

Wavelength

1/

Emittance

2/

CTm

2 a ~

s Microns XI 00 X100 X100

1.18 82.0 .77 1.84

1.25 83.5 .88 1.19

1.33 84.5 .97 1.53

1.40 85.1 .70 1.67

1.48 85.1 .82 1.59

1.58 84.7 .85 1.50

1.68 84.2 .58 1.60

1.81 83.9 .66 1.55

1.98 83.5 1.07 1.66

2.23 84.5 .81 1.22

2.51 83.3 .81 .98

2.73 83.2 .85 .88

2.92 82.8 .83 .88

3.14 82.7 .66 .78

3.35 82.6 .56 .73

3.56 82.5 .56 .75

3.77 82.4 .63 .76

3.98 82.1 .70 .89

4.20 82.1 .58 .93

4.41 82.1 .66 .76

4.58 82.1 .68 .65

4.76 81.9 .50 .61

4.91 81.7 .67 .64

5.07 81.6 .80 .39

5.21 81.7 .77 .45

5.34 81.6 .93 .52

5.47 81.6 .85 .52

5.60 81.5 .87 .55

5.76 81.3 .72 .64

5.90 81.3 .66 .67

6.04 81.3 .81 .58

6.16 81.1 .65 .58

6.28 81.1 .83 .48

6.41 81.1 .66 .55

6.53 81.1 .63 .57
20 -

TABLE II cont'd.

NORMAL SPECTRAL EMITTANCE OF

OXIDIZED INCONEL WORKING STANDARDS AT 800*K

Wavelength Emittance —

m

Microns X100 X100 X100

6.64 81.1 .65 .49

6.76 81.3 .63 .47

6.87 81.5 .62 .47

6.97 81.8 .76 .55

7.07 82.1 .70 .49

7.19 82.8 1.40 • .80

7.32 82.8 .55 .59

7.44 83.1 .73 .60

7.56 83.3 .66 .61

7.66 83.6 .64 .56

7.77 83.9 .67 .60

7.88 84.2 .66 .61

7.98 85.0 .62 .66

8.08 85.9 .67 .60

8.18 86.5 .67 .62

8.28 87.1 .62 .64

8.38 87.5 .57 .65

8.47 87.5 .70 .75

8.57 87.7 .66 .80

8.66 87.9 .70 .84

8.75 88.1 .81 .95

8.84 88.2 .67 .88

8.93 88.4 .61 .92

9.01 88.4 1.60 1.15

9.10 88.9 1.04 .83

9.18 89.1 .73 .80

9.26 89.3 .78 .83

9.35 89.4 .72 .82

9.43 89.2 *68 .73

9.51 88.8 .73 .76

9.67 88.4 .68 .82

9.83 88.3 .67 .89

10.00 88.3 .68 .72

10.15 88.6 .60 .75

10.30 88.9 .50 .82
- 21

TABLE II cont'd.

NORMAL SPECTRAL EMITTANCE OF

OXIDIZED INCONEL WORKING STANDARDS AT 800°K

Wavelength Emittance—

in 2

Microns X100 X100 xioo

10.46 89.4 .56 .84

10.61 89.5 .78 .98

10.76 89.7 .74 .93

10.91 90.0 .57 .74

11.05 90.2 .73 .71

11.19 90.5 .57 .81

11.32 90.6 .64 .81

11.45 90.7 .79 .87

11.58 90.8 .67 .85

11.72 91.1 .67 .75

11.84 91.3 .65 .67

11.97 91.5 .57 .78

12.09 91.6 .68 .81

12.22 91.8 .77 .76

12.35 92.0 .70 .77

12.48 92.4 .64 .80

12.60 92.9 .60 .89

12.72 93.0 .65 .95

12.85 93.3 .68 .89

12.98 93.4 .55 .80

13.10 93.8 .52 .83

13.22 94.1 .53 .79

13.34 94.2 .59 .81

13.46 94.3 .59 .90

13.58 94.4 .59 .84

13.69 94.3 .61 .86

13.81 94.0 .61 .80

13.93 93.3 .53 .85

14.03 91.7 .59 .85

14.14 89.8 .67 .82

14.25 87.6 .69 .86

14.36 85.2 .79 .91

14.47 82.8 .79 .92

14.58 80.5 .74 .92

14.68 78.2 .70 .87
22

TABLE II cont'd.

NORMAL SPECTRAL EMITTANCE OF

OXIDIZED INCONEL WORKING STANDARDS AT 800°

Wavelength Emittance^ a ym

2/

CT s Microns X100 X100 XI 00

14.79 75.9 .72 .91

14.90 73.9 .61 .84

15.01 72.3 .79 .89

15.11 70.8 .57 .89

1/ Average of 18 measured values, three each on six specimens

2/ See footnote 1 on page 3 in the text.
23

TABLE II cont'd.

NORMAL SPECTRAL EMITTANCE OF

OXIDIZED INCONEL WORKING STANDARDS AT 1100°K

Wavelength Emittance—

2/

°m rr 2 /

CT S Microns X100 X100 X100

1.07 89.4 1.10 3.13

1.12 89.5 .80 3.28

1.18 89.4 .76 3.17

1.25 89.3 .59 3.17

1.33 89.1 .57 2.87

1.40 88.9 .55 2.75

1.48 88.6 .66 2.51

1.58 88.1 .70 2.31

1.68 87.7 .77 2.05

1.81 87.4 .59 1.69

1.98 86,9 .50 1.61

2.23 86.7 .52 1.43

2.51 86.3 .55 1.53

2.73 85.7 .59 1.44

2.92 85.5 .60 1.48

3.14 85.4 .52 1.41

3.35 85.2 .53 1.36

3.56 85.0 .53 1.36

3.77 84.9 .58 1.25

3.98 84.8 .59 1.19

4.20 84.6 .66 1.11

4.41 84.5 .52 .92

4.58 84.4 .55 1.01

4.76 84.4 .60 .97

4.91 84.2 .81 1.32

5.07 84.3 .60 1.22

5.21 84.4 .63 1.17

5.34 84.5 .56 1.10

5.47 84.6 .53 1.11

5.60 84.5 .54 .97

5.76 84.0 1.21 1.45

5.90 83.9 .97 1.12

6.04 84.0 .78 .97

6.16 83.8 .69 .87

6.28 83.9 .54 .90
- 24

TABLE II cont'd.

NORMAL SPECTRAL EMITTANCE OF

OXIDIZED INCONEL WORKING STANDARDS AT 1100°K

Wavelength Emittance—^ 2/ 2/

ffs -

Microns X100 X100 X100

6.41 84.0 .61 .93

6.53 83.9 .51 .95

6.64 84.0 .51 .99

6.76 84.2 .57 .99

6.87 84.6 .64 1.03

6.97 84.8 .52 .95

7.07 85.0 .55 .91

7.19 85.2 .53 .87

7.32 85.3 .47 .80

7.44 85.4 .46 .70

7.56 85.6 .44 .67

7.66 85.7 .50 .60

7.77 86.0 .50 .69

7.88 86.2 .57 .67

7.98 86.7 .51 .77

8.08 87.1 .49 .74

8.18 87.6 .51 .56

8.28 88.0 .62 .54

8.38 88.4 .49 .59

8.47 88.6 .53 .56

8.57 88.7 .62 .48

8.66 88.9 .50 .51

8.75 88.9 .57 .45

8.84 89.0 .64 .51

8.93 89.3 .46 .50

9.01 89.4 .42 .60

9.10 89.5 .43 .65

9.18 89.7 .38 .73

9.26 89.8 .44 .74

9.35 89.9 .47 .72

9.43 90.0 .49 .62

9.51 90.0 .62 .47

9.67 89.8 .58 .27

9.83 89.9 .50 .33

10.00 89.9 .53 .44
25 -

TABLE II cont'd.

NORMAL SPECTRAL EMITTANCE OF

OXIDIZED INCONEL WORKING STANDARDS AT 1100°K

Wavelength Emittance—

a

I-' 2 as"

Microns X100 X100 X100

10.15 90.0 .39 .48

10.30 90.1 .39 .49

10.46 90.2 .47 .45

10.61 90.4 .54 .48

10.76 90.7 .46 .65

10.91 90.9 .38 .71

11.05 91.2 .43 .60

11.19 91.4 .42 .45

11.32 91.6 .47 .33

11.45 91.6 .54 .37

11.58 91.9 .50 .42

11.72 92.1 .37 .53

11.84 92.2 .33 .53

11.97 92.3 .58 .47

12.09 92.5 .57 .41

12.22 92.7 .59 .45

12.35 93.0 .59 .43

12.48 93.2 .52 .53

12.60 93.5 .44 .65

12.72 93.7 .48 .62

12.85 93.8 .53 .57

12.98 94.0 .61 .55

13.10 94.4 .56 .52

13.22 94.9 .62 .71

13.34 95.1 .51 .77

13.46 95.3 .51 .70

13.58 95.4 .63 .64

13.69 95.4 .71 .67

13.81 95.4 .59 .62

13.93 95.4 .46 .71

14.03 95.3 .38 .94

14.14 94.8 .37 1.11

14.25 93.8 .42 1.16

14.36 92.4 .66 1.44

14.47 90.9 .70 1.52
26 -

TABLE II cont'd.

NORMAL SPECTRAL EMITTANCE OF

OXIDIZED INCONEL WORKING STANDARDS AT 1100°K

Wavelength _ , 1/ Emittance — 2/ am

“ 2/

®s~

Microns X100 X100 X100

14.58 89.1 .58 1.57

14.68 87.3 .53 1.65

14.79 85.4 .48 1.80

14.90 83.3 .49 1.89

15.01 81.3 .63 2.04

15.11 80.3 4.68 3.36

.1/ Average of 18 measured values, three each on six specimens.

2/ See footnote 1 on page 3 In the text.
27 -

TABLE II cont'd.

NORMAL SPECTRAL EMITTANCE OF

OXIDIZED INCONEL WORKING STANDARDS AT

Wavelength Emittance”^ 2/

CTm~

Microns

,

X100 X100

1.07 91.7 1*57

1.12 91.4 1.59

1.18 91.2 1.45

1.25 91.0 1.63

1.33 90.8 1.53

1.40 90.4 1.22

1.48 89.8 1.26

1.58 89.4 1.13

1.68 88.8 .96

1.81 88.3 .88

1.98 87.9 .72

2.23 87.4 .93

2.51 86.9 1.15

2.73 86.5 .83

2.92 86.3 .83

3.14 86.1 .84

3.35 86.0 .72

3.56 86.0 .71

3.77 86.0 .63

3.98 86.0 .66

4.20 85.8 .42

4.41 85.7 .67

4.58 85.7 .73

4.76 85.6 .54

4.91 85.6 .54

5.07 85.6 .49

5.21 85.6 .61

5.34 85.6 .61

5.47 85.6 .63

5.60 85.6 .65

5.76 85.5 .75

5.90 85.4 .49

6.04 85.5 .53

6.16 85.5 .56

6.28 85.6 .31

1300*K

X100

2.87

2.68

2.52

2.37

2.10

1.90

1.71

1.57

1.57

1.45

1.46

1.38

1.53

1.21

1.15

1.01

.94

.96

.94

.79

.84

.91

.85

.74

.74

.71

.77

.79

.83

.79

.86

.80

.79

.81

.81
28 -

TABLE II cont'd.

NORMAL SPECTRAL EMITTANCE OF

OXIDIZED INCONEL WORKING STANDARDS AT 1300*K

Wavelength Emittance^ O —

/

m

a 1/

s Microns X100 X100 X100

6.41 85.7 .38 .80

6.53 85.7 .63 .71

6.64 85.7 .51 .68

6.76 85.8 .56 .69

6.87 86.0 .52 .77

6.97 86.1 .60 .69

7.07 86.1 .59 .75

7.19 86.3 .70 .69

7.32 86.5 .71 .68

7.44 86.7 .65 .88

7.56 86.9 .58 .87

7.66 87.0 .61 .95

7.77 87.3 .45 .97

7.88 87.5 .42 .88

7.98 87.7 .37 .85

8.08 88.0 .40 .79

8.18 88.2 .54 .67

8.28 88.4 .42 .65

8.38 88.8 .36 .62

8.47 89.4 1.05 .66

8.57 89.4 .64 .55

8.66 89.5 .64 .55

8.75 89.6 .59 .61

8.84 89.7 .56 .66

8.93 89.8 .56 .67

9.01 90.0 .49 .82

9.10 90.1 .58 .76

9.18 89.9 .98 .98

9.26 90.2 .68 .76

9.35 90.3 .51 .77

9.43 90.3 .57 .80

9.51 90.4 .69 .79

9.67 90.6 .99 .72

9.83 90.4 .89 .71

10.00 90.3 .83 .72
29

TABLE II cont'd

NORMAL SPECTRAL EMITTANCE OF

OXIDIZED INCONEL WORKING STANDARDS AT 1300°K

Wavelength Emittance”/ a 3/

m s Microns X100 X100 X100

10.15 90.4 .72 .79

10.30 90.5 1.38 .93

10.46 90.8 .79 .79

10.61 90.9 1.36 .95

10.76 91.0 .54 .82

10.91 91.2 .55 .61

11.05 91.4 .59 .81

11.19 91.7 .50 .84

11.32 92.0 .54 .78

11.45 92.1 .58

v .71

11.58 92.2 .47 .66

11.72 92.3 .58 .83

11.84 92.6 .53 .80

11.97 92.9 .51 .72

12.09 93.0 .56 .72

12.22 93.2 .52 .62

12.35 93.3 .54 .69

12.48 93.6 .51 .76

12.60 93.9 .45 .70

12.72 94.3 .38 .72

12.85 94.4 .48 .72,

12.98 94.7 .74 .59

13.10 94.9 .60 .57

13.22 95.1 .52 .64

13.34 95.5 .67 .68

13.46 95.6 .40 .67

13.58 95.8 .50 .59

13.69 95.8 .57 .64

13.81 96.0 .85 .56

13.93 96.0 .50 .63

14.03 95.8 .46 .62

14.14 95.5 .53 .75

14.25 94.9 .62 .88

14.36 94.0 1.13 1.06

14.47 93.1 .79 1.40
30

TABLE II cont'd.

NORMAL SPECTRAL EMITTANCE OF

OXIDIZED INCONEL WORKING STANDARDS AT 1300°K

Wavelength Emittancer^

2/ am •, 2'

Microns X100 X100 XI 00

14.58 91.9 1.09 2.00

14.68 90.1 1.01 2.09

14.79 88.4 1.04 2.28

14.90 86.4 .99 2.51

15.01 84.5 1.07 2.57

15.il 82.7 1.05 2.73

1/ Average of 18 measured values, three each on six specimens.

2 / See footnote 1 on page 3 in the text.
NORMAL

SPECTRAL

EMITTANCE

31

Fig. 1. Normal spectral emittance of 0.484- inch disc wgrking

standards of platinum- 13% rhodium alloy at 800 K.

The plotted values are averages of six measured

values, three each on two specimens.
NORMAL

SPECTRAL

EMITTANCE

32

WAVELENGTH, MICRONS

Fig. 2. Normal spectral emittance of 0.484-inch disc working

standards of platinum- 13% rhodium alloy at 1100 K.

The plotted values are averages of six measured

values, three each on two specimens.
NORMAL

SPECTRAL

EMITTANCE

33

Fig. 3. Normal spectral emittance of 0.484-inch disc working

standards of platinum-13% rhodium alloy at 1300 K.

The plotted values are averages of six measured

values, three each on two specimens.
STANDARD

DEVIATION

OF

EMITTANCE

MEASUREMENTS

34

Fig. 4. Spectral distribution of two categories of standard

deviations, each computed from six measured emittance

values obtained at 800 K, three each on two specimens

of platinum- 13% rhodium alloy. The upper curve re- presents standard deviations due to differences in

emittance between specimens, identified as rrg in the

text. The lower curve represents standard deviations

due to random error, identified as CTm

in the text.

In both curves, each point represents the moving

average of five adjacent values.
STANDARD

DEVIATION

OF

EMITTANCE

MEASUREMENTS

35 -

Fig. 5. Spectral distribution of two categories of standard

deviations, each computed from six measured emittance

values obtained at 1100 K, three each on two specimens

of platinum- 13% rhodium alloy. The upper curve re- presents standard deviations due to differences in

emittance between specimens, identified as crs in the > text. The lower curve represents standard deviations

due to random error, identified as cTm

in the text.

In both curves, each point represents the moving

average of five adjacent values.
STANDARD

DEVIATION

OF

EMITTANCE

MEASUREMENTS

36

Fig. 6. Spectral distribution of two categories of standard

deviations, each computed from six measured emittance

values obtained at 1300°K, three each on two specimens

of platinum- 13% rhodium alloy. The upper curve re- presents standard deviations due to differences in

emittance between specimens, identified as rr s in the

text. The lower curve represents standard deviations

due to random error, identified as in the text.

In both curves, each point represents the moving

average of five adjacent values.
NORMAL

SPECTRAL

EMITTANCE

37

WAVELENGTH, MICRONS

Fig. 7. Normal spectral emittance of 0.484 -inch disc working

standards of oxidized sandblasted Inconel at 800 K.

The plotted values are averages of 18 measured values,

three each on six specimens.
NORMAL

SPECTRAL

EMITTANCE

38

Fig. 8. Normal spectral emittance of 0.484-inch disc working

standards of oxidized sandblasted Inconel at 1100 K.

The plotted values are averages of 18 measured values,

three each on six specimens.
NORMAL

SPECTRAL

EMITTAMCE

39

Fig. 9. Normal spectral emittance of 0.484 inch-disc working

standards of oxidized sandblasted Inconel at 1300 K

The plotted values are averages of 18 measured values,

three each on six specimens.
STANDARD

DEVIATION

OF

EMITTANCE

MEASUREMENTS

40

Fig. 10. Spectral distribution of two categories of standard

deviations, each computed from 18 measured emittance

values obtained at 800 K, three each on six specimens

of oxidized sandblasted Inconel. The upper curve re- presents standard deviations due to differences in

emittance between specimens, identified as rr s in the

text. The lower curve represents standard deviations

due to random error, identified as rrmin the text.

In both curves, each point represents the moving

average of five adjacent values.
STANDARD

DEVIATION

OF

EMITTANCE

MEASUREMENTS

41

Fig. 11. Spectral distribution of two categories of standard

deviations, each computed from 18 measured emittance

values obtained at 1100 K, three each on six specimens

of oxidized sandblasted Inconel. The upper curve re- presents standard deviations due to differences in

emittance between specimens, identified as as in the

text. The lower curve represents standard deviations

due to random error, identified as a in the text.

In both curves, each point represents the moving

average of five adjacent values.
STANDARD

DEVIATION

OF

EMITTANCE

MEASUREMENTS

- 42

Fig. 12. Spectral distribution of two categories of standard

deviations, each computed from 18 measured emittance

values obtained at 1300 K, three each on six specimens

of oxidized sandblasted Inconel. The upper curve re- presents standard deviations due to differences in

emittance between specimens, identified as rrs in the

text. The lower curve represents standard deviations

due to random error, identified as rr in the text.

In both curves, each point represents the moving

average of five adjacent values.
U. S. DEPARTMENT OF COMMERCE

Luther H. Hodges, Secretary

NATIONAL BUREAU OF STANDARDS

A. V. Astin, Director THE NATIONAL BUREAU OF STANDARDS

The scope of activities of the National Bureau of Standards at its major laboratories in Washington, D.C.,and

Boulder, Colorado, is suggested in the following listing of the divisions and sections engaged in technical work.

In general, each section carries out specialized research, development, and engineering in the field indicated by

its title. A brief description of the activities, and of the resultant publications, appears on the inside of the

front cover. WASHINGTON, D. C.

Electricity. Resistance and Reactance. Electrochemistry. Electrical Instruments. Magnetic Measurements.

Dielectrics. High Voltage. Absolute Electrical Measurements.

Metrology. Photometry and Colorimetry. Refractometrv. Photographic Research. Length. Engineering Metrology.

Mass and Volume.

Heat. Temperature Physics. Heat Measurements. Cryogenic Physics. Equation of State. Statistical Physics.

Radiation Physics. X-ray. Radioactivity. Radiation Theory. High Energy Radiation. Radiological Equipment.

Nucleonic Instrumentation. Neutron Physics.

Analytical and Inorganic Chemistry. Pure Substam es. Spectrochemistry. Solution Chemistry. Standard Refer- ence Materials. Applied Analytical Research. Crystal Chemistry.

Mechanics. Sound. Pressure and Vacuum. Fluid Mechanics. Engineering Mechanics. Rheology. Combustion

Controls. Polymers. Macromolecules: Synthesis and Structure. Polymer Chemistry. Polymer Physics. Polymer Characterization. Polymer Evaluation and Testing. Applied Polymer Standards and Research. Dental Research.

Metallurgy. Engineering Metallurgy. Metal Reactions. Metal Physics. Electrolysis and Metal Deposition.

Inorganic Solids. Engineering Ceramics. Glass. Solid State Chemistry. Crystal Growth. Physical Properties.

Crystallography.

Building Research. Structural Engineering. Fire Research. Mechanical Systems. Organic Building Materials. Codes and Safety Standards. Heat Transfer. Inorganic Building Materials. Metallic Building Materials. Applied Mathematics. Numerical Analysis. Computation. Statistical Engineering. Mathematical Physics. Operations Research. Data Processing Systems. Components and Techniques. Computer Technology. Measurements Automation.

Engineering Applications. Systems Analysis.

Atomic Physics. Spectroscopy. Infrared Spectroscopy. Far Ultraviolet Physics. Solid State Physics. Electron Physics. Atomic Physics. Plasma Spectroscopy.

Instrumentation. Engineering Electronics. Electron Devices. Electronic Instrumentation. Mechanical Instru- ments. Basic Instrumentation. Physical Chemistry. Thermochemistry. Surface Chemistry. Organic Chemistry. Molecular Spectroscopy. Ele- mentary Processes. Mass Spectrometry. Photochemistry and Radiation Chemistry.

Office of Weights and Measures. BOULDER, COLO.

CRYOGENIC ENGINEERING LABORATORY

Cryogenic Processes. Cryogenic Properties of Solids. Cryogenic Technical Services. Properties of Cryogenic

Fluids. CENTRAL RADIO PROPAGATION LABORATORY

Ionosphere Research and Propagation. Low Frequency and VeTM Low Frequency Research. Ionosphere Research. Prediction Services. Sun-Earth Relationships. Field Engineering. Radio Warning Services. Vertical Soundings Research. Troposphere and Space Telecommunications. Data Reduction Instrumentation. Radio Noise. Tropospheric Measurements. Tropospheric Analysis. Spectrum Utilization Research. Radio-Meteorology. Lower Atmosphere

Physics.

Radio Systems. Applied Electromagnetic Theory. High Frequency and Very High Frequency Research. Fre- quency Utilization. Modulation Research. Antenna Research. Radiodetermination.

Upper Atmosphere and Space Physics. Upper Atmosphere and Plasma Physics. High Latitude Ionosphere

Physics. Ionosphere and Exosphere Scatter. Airglow and Aurora. Ionospheric Radio Astronomy.

RADIO STANDARDS LABORATORY

Radio Standards'Physics. Frequency and Time Disseminations. Radio and Microwave Materials. Atomic Fre- quency and Time-Interval Standards. Radio Plasma. Microwave Physics.

Radio Standards Engineering. High Frequency Electrical Standards. High-Frequency Cal ibration Services. High

Frequency Impedance Standards. Microwave Calibration Services. Microwave Circuit Standards. Low Frequency

Calibration Services.

Joint Institute for Laboratory Astrophysics- NBS Group (Univ. of Colo.).