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5. TITLES AND ABSTRACTS OF NBS PUBLICATIONS, 19791

5.1. PAPERS FROM THE JOURNAL OF RESEARCH OF THE NATIONAL BUREAU OF STANDARDS, VOLUME 84, JANUARY-DECEMBER 1979

January-February 1979

Diffusion coefficients of the 45S and 50S states of the large ribosomal subunit of E. coli by quasielastic light scattering, C. C. Han, I. N. Serdyuk, and H. Yu, J. Res. Nat. Bur. Stand. (U.S.), 84, No. 1, 1-8 (Jan.-Feb. 1979).

Key words: diffusion coefficient; E. coli ribosomal subunit; quasielastic light scattering; 45S and 50S.

The transitional diffusion coefficients of the 45S and 50S states of the large ribosomal subunit of E. coli were determined from the spectral distributions of quasielastically scattered light with a 5 mW He-Ne laser as the source. The spectral analysis was performed by directly Fourier transforming the photocurrent and fitting to double-Lorentzian profile via a non-linear regression routine. A small amount (about 1%) of strongly scattering contaminants required the double-Lorentzian profile in order to extract the diffusion coefficients of the principal components. The results are: D20°, w(45S) = (1.79 ± 0.12) × 10:" cm3/sec, and D20°, w(50S) = (1.91 ± 0.06) × 10 cm3/sec, the latter being in accord with those reported in the literature. The transition from the 50S state to the 45S state is not attended by a change in its molecular weight if the partial specific volumes are assumed to be the same.

System for assessing eye injury potential of propelled objects, R. E. Berger, J. Res. Nat. Bur. Stand. (U.S.), 84, No. 1, 9-19 (Jan.-Feb. 1979).

Key words: eye injury; impact; ocular contusion; projectiles; propelled objects; test methods; toy safety.

A test system is proposed to evaluate the ocular injury potential of propelled objects. The object in question is fired into a thin rubber pad, and the force of impact and the rise time are measured. For a set of test projectiles, the response of the system was shown to correlate with the likelihood of injury, as predicted by a mathematical model. The response was further related to ocular injury tolerance curves which were generated by the math model using data from impact injuries to real eyes. Enhancing Fortran to aid manipulation of large structured matrices, H. J. Greenberg and J. E. Kalan, J. Res. Nat. Bur. Stand. (U.S.), 84, No. 1, 21-47 (Jan.-Feb. 1979).

Key words: data pooling; data structures; mathematical programming; matrices; name generation; operations research; programming languages; sparse matrices.

This paper presents, for wider discussion by the technical community, suggested means for enhancing (ANS) FORTRAN in order to accommodate the needs of operations research analysts in programming tasks involving large, structured or sparse matrices. Such needs frequently arise in connection with large-scale optimization problems. Most of the text deals with fundamental concepts and descriptions of syntax, but related data structures are also treated. Proposed new capabilities include exploitation of repeated values among matrix entries,

'The various NBS publications series are grouped under subheadings within this section. If a particular publications series is sought, consult the table of contents or the edge index on the back cover.

space-saving "quasi-dynamic storage allocation," and easy setup for construction of large matrices from smaller ones (with the actual construction deferable until and if the need arises). Cutting the d-cube, J. Lawrence, J. Res. Nat. Bur. Stand. (U.S.), 84, No. 1, 49-53 (Jan.-Feb. 1979).

Key words: cube; geometry; hyperplane.

Some problems concerned with cutting faces of the cube with affine or linear spaces are considered. It is shown that through any d-3 points of Rd there passes a hyperplane which cuts all the facets of the d-cube. Furthermore, it is shown that if m <d-1 and ď' <d-[(m + 1)/3], then no m-dimensional affine subspace of Rd cut all the d'-dimensional faces of the cube.

March-April 1979

A novel method for analyzing silver sediment with high precision, R. S. Davis and V. E. Bower, J. Res. Nat. Bur. Stand. (U.S.), 84, No. 2, 157-160 (Mar.-Apr. 1979).

Key words: controlled potential; coulometry; electrochemical equivalent of silver; electrochemistry; Faraday; potentiostat; silver; silver analysis.

A technique has been devised which is sufficiently accurate to aid in an electrochemical determination of the Faraday constant using the silver coulometer. The technique is used to recover the silver residue which falls from the anode during operation of the silver coulometer. In contrast to previous efforts at recovery, which involved weighing of the silver residue, the method here described is to convert the silver atoms to ions and then to plate the silver onto a cathode held at constant potential with respect to a reference electrode. The current involved in the electrolysis is integrated electronically. An overall standard deviation of 5 μg is achieved for samples ranging in size from 400 μg to 1.8 mg.

Psychrometric wet elements as a basis for precise physico-chemical measurements, R. G. Wylie, J. Res. Nat. Bur. Stand. (U.S.), 84, No. 2, 161-177 (Mar.-Apr. 1979).

Key words: convective heat transfer; convective mass transfer; emissivity of water; evaporation coefficient; humidity measurement; monomolecular film; psychrometer; psychrometry; radiative heat transfer; temperature depression; water vapor measurement; wet bulb; wet element. Under appropriate conditions, psychrometric wet elements of simple design can be highly reproducible in behavior. A temperature depression of 10 K can be reproducible from element to element within 2 mK. The properties of a wet element can be determined very accurately by direct comparisons with other wet elements in a common airstream. Comparisons with one specially developed type show the effects of practical waterretaining coverings. Comparisons with another type, which simulates the fully calculable flat-plate system, then give the behavior in absolute terms.

A cotton-yarn covering increases the psychrometer coefficient A by only 0.2 percent. The departure of the flow around a cylinder from laminar boundary-layer flow increases it by 0.7 percent.

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Enthalpies of solution of the nucleic acid bases. 5. Adenine in aqueous hydrochloric acid, aqueous sodium hydroxide, methanol, and ethanol, M. V. Kilday, J. Res. Nat. Bur. Stand. (U.S.), 84, No. 3, 231-240 (May-June 1979).

Key words: adenine; enthalpy of dissociation; enthalpy of protonation; enthalpy of reaction; enthalpy of solution; nucleic acid bases; solution calorimetry; thermochemistry. The two preceding papers in this series described the results of measurements of the enthalpies of solution in water for some of the bases of the nucleic acids. In this work the enthalpies of solution or reaction of adenine (Ade), C ̧H ̧N, or 6-amino purine, in other solvents are reported.

Sample preparation in ion-chromatography, W. F. Koch, J. Res. Nat. Bur. Stand. (U.S.), 84, No. 3, 241-246 (May-June 1979).

ion

Key words: conductivity; ion-chromatography; exchange; liquid chromatography; oil; oyster. Ion-chromatography, a relatively new technique in analytical chemistry, has already shown great promise toward solving complex trace analysis problems, in particular the speciation and quantitation of anions. It is especially attractive to the field of microanalysis. The method of sample preparation, however, is crucial in order to realize this capacity. Existing microanalytical methods nearly always must be modified to be compatible with ion-chromatography, and often, more extensive sample cleanup is required than is needed for "single species" methods. These considerations have been applied to the determination of chloride and bromide in waste oil, and to the analysis of oyster tissue. Pretreatment with polystyrene resin and ion-exchange resin is discussed.

Miniaturization of normal-state and superconducting striplines, R. L. Kautz, J. Res. Nat. Bur. Stand. (U.S.), 84, No. 3, 247259 (May-June 1979).

Key words: copper; niobium; stripline; superconductivity; surface impedance.

The properties of normal-state and superconducting striplines are calculated as a function of miniaturization. For normal conductors the Reuter-Sondheimer theory is applied in order to account for the effects of finite film thickness and mean free path. For superconductors the Mattis-Bardeen theory is used in order to include effects due to the energy gap. Calculations for three example conductors, copper at 295 K and 4.2 K and niobium at 4.2 K, examine the attenuation, dispersion, and

characteristic impedance of striplines as a function of frequency and dielectric thickness. Simulations of pulse transmission are used to evaluate the utility of the example striplines for high-speed digital applications.

July-August 1979

Enthalpies of solution of KBг, KI, KIO,, and KIO, in H2O, M. E. Efimov, G. N. Klevaichuk, V. A. Medvedev, and M. V. Kilday, J. Res. Nat. Bur. Stand. (U.S.), 84, No. 4, 273-286 (July-Aug. 1979).

Key words: endothermic solution reactions; enthalpy of solution; KBr, KI, KIO, KIO; solution calorimetry; thermochemistry; tris(hydroxymethyl)aminomethane.

Enthalpy of solution measurements of four potassium salts in H2O were made in either an adiabatic or an isoperibol calorimeter or both (see p. 273 for table summarizing the measured and recommended values).

The value for KIO, has been corrected for the hydrolysis of the periodate ion. The AC, = −(82.5 ± 4.3)J·mol-1·K-1 for the unhydrolysed reaction. For the reaction of KBr in H2O, AC, was measured as −(166.6 ± 7.2)J·mol−1·K-1 in the temperature range 298 K to 319 K.

ported

Measurements with the isoperibol calorimeter are also refor the endothermic reaction of tris(hydroxymethyl)aminomethane, SRM 724a, in aqueous NaOH(0.05 mol·L-1).

Comparisons of measurements by different calorimeters on the same samples reveal unidentified calorimetric errors for endothermic reactions which are greater than the imprecision of the measurements.

A preliminary study of the fluid mechanics of liquid penetrant testing, S. Deutsch, J. Res. Nat. Bur. Stand. (U.S.), 84, No. 4, 287-292 (July-Aug. 1979).

Key words: defect geometry; fluid elasticity; liquid penetrant testing; Rideal-Washburn equation; surface tension.

Some aspects of the fluid mechanics of liquid penetrant testing are considered. Penetration is represented by surface tension driven flow into defects of small defect width to depth ratio. Defect width is chosen so that both gravitational and non-continuum effects may be ignored. Penetration time is found to follow a Rideal-Washburn relation, in which:

1 ~ (Pμ)/(yR cos 0)

where is time, I defect depth, μ the dynamic viscosity, y the surface tension, R the defect width and the contact angle. The proportionality constant, however, is shown to be strongly dependent on defect geometry and penetrant application procedure. The effect of slight fluid elasticity is shown to be negligible.

Exact coefficients of the limit cycle in Van der Pol's equation, A. Deprit and D. S. Schmidt, J. Res. Nat. Bur. Stand. (U.S.), 84, No. 4, 293-297 (July-Aug. 1979).

Key words: algebra by computer; differential equations; mathematical software; non-linear oscillations.

A program generator to manipulate automatically Poisson series over the field of rational numbers is applied to develop the limit cycle of Van der Pol's equation in the powers of the small parameter. The results indicate that the recurrence relations in what Melvin calls the algorithm of the shifted phase are stable.

Tensile behavior of some mathematical models of paper networks, J. C. Smith, J. Res. Nat. Bur. Stand. (U.S.), 84, No. 4, 299-318 (July-Aug. 1979).

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