Karbidausscheidungen beim Anlassen eines gehärteten Wälzlagerstahles mit rd. 1% C und 1,5 % Cr

Elektronenmikroskopische Auflicht-, Durchstrahlungs- und Feinbereichsbeugungsuntersuchungen an kompakten oder folienförmigen Proben aus einem Stahl mit rd. 1% C und 1,5% Cr nach unterschiedlichem Härten und nach darauffolgendem Anlassen bis auf rd. 300 °C bei unterschiedlicher Anlaßdauer. Folgerungen besonders über die bei den jeweiligen Bedingungen der Wärmebehandlung auftretenden Karbidausscheidungen.     

The Shift of the Arterial Pulse-Wave Foot on Recordings With a Rising or Falling Baseline

Recordings of arterial pulse waves often appear on a rising or falling baseline. This causes a shift in the position of the pulse-wave foot as compared to its position on the horizontal base-line. The magnitude of this shift is unknown. Workers therefore tend to disregard pulse-wave recordings with sloping baselines when measuring foot-to-foot pulse-wave velocities. A formula was derived that allows an estimation of the upper limit of the shift in the position of the pulse-wave foot to be tm = l000n/157 ms, where n = b/A, b is the slope of the baseline, and A is one-half the arterial pulse-wave amplitude. In the majority of recordings with sloping baselines, n < 0.5 and tm does therefore not exceed 3 ms. Compared to the measured foot-to-foot time intervals, tm is usually small enough to be disregarded. In cases where n is larger, the formula can be used to estimate the upper limit of the error caused by the sloping base-line.     

On procedures as open subroutines. I

Summary An ALGOL program with open subroutines or macro program is a program whose procedures may be implemented as open subroutines. A macro program may be considered to be an abbreviated notation of a program without procedures. It is proved that the so called macro program problem is algorithmically unsolvable for ALGOL 60 and other ALGOL-like languages : There does not exist any algorithm which decides for any given program whether it is a macro program or not (Theorem 4.3 and 4.4 in part II). Sublanguages of ALGOL-like languages for which the macro program problem is solvable are furtheron investigated (Theorem 4.1, 5.2–5.5 in part II). For this purpose macro grammars theory is applied.The methods of the paper are developped in part I and the key lies in a generalized langugage ALGOL 60-P-G which has the so called modularity property : There is an effective process which constructs for every original ALGOL 60-P-G program a formally equivalent one without procedure nesting (Theorem 3.3). The process mainly works by eliminating global procedure parameters (Theorem 3.1). ALGOL 60 and other known ALGOL-like languages do not have the modularity property (Theorem 3.4). Elimination of global procedure parameters is successful only for sublanguages of ALGOL 60 (Theorem 2.3–2.7).     

Theoretical atomic inner-shell energy levels, 70 ≤ Z ≤ 106

Theoretical 1s, 2s, $\text{2p}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}$, and $\text{2p}{}_{\mathrm{<mtext>3</mtext><mtext>2</mtext>}}$ energy levels in neutral atoms with 70 ≤ Z ≤ 106 are listed. The computations are relativistic and include complete relaxation. The electric energies are based on Dirac-Hartree-Slater wave functions; a first-order correction to the local approximation is made. The Breit-interaction energy and vacuum-polarization energy are listed separately, and a self-energy correction is included. These calculations differ from earlier work by the authors in that a more accurate, frequency-dependent expression for the Breit energy is employed, a Fermi (rather than uniform) distribution of the nuclear charge is assumed, and a screened self-energy correction is applied to the 1s, 2s, $\text{2p}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}$, and $\text{2p}{}_{\mathrm{<mtext>3</mtext><mtext>2</mtext>}}$ levels. Comparison of results with 1967 experimental values adopted by Bearden and new work of Borchert shows better agreement than is provided by earlier calculations with frequency-independent Breit interaction and a uniform nuclear charge distribution.     

Vergleich zwischen strengen und elementaren Lösungen der Plastizitätstheorie für ebene Umformung

Grundgleichungen der elementaren Plastizitätstheorie (EPT) bei beliebiger Randkontur. Grundgleichungen einer erweiterten elementaren Plastizitätstheorie (EEPT) bei beliebiger Randkontur. Vergleich von elementaren Lösungen mit strengen Lösungen. Vergleich von erweiterten elementaren Lösungen mit strengen Lösungen. Vergleich von elementaren Lösungen mit strengen Lösungen bei Anisotropie.     

Influence of Metallurgical Conditions on the Lining Wear in the Kaldo Process

The influence of different metallurgical conditions on the lining wear in the Kaldo process when refining high phosphorus iron has been systematically investigated revealing the following main featuresThe lining is protected by a lime-saturated layer of slag during the main part of the first blowing period.The lining wear starts in connection with the melting of this protective layer which occurs at the end of the first period. After that, the wear rate increases rapidly.The rapid increase of the lining wear is caused by direct combustion in a strongly oxidizing atmosphere of liquid iron which has been dragged up on the lining surface.By decreasing the oxygen activity in the furnace atmosphere at the end of the oxygen-blowing period the wear can be decreased considerably. In practice this has been solved by directing the oxygen jet with high impulse steeply into the bath during this period of the blowing. In this way the lining life in Domnarvet’s 30 ton Kaldo furnace has been increased by about 75% without reducing the steel yield. Blowing time and consumption of oxygen have at the same time decreased by about 10%.     

Der Einfluß der Keimbildung auf die irreversiblen Dimensionsänderungen von Reinsteisen bei zyklischen α/γ/α-Umwandlungen

Versuchsanordnung mit symmetrischem Temperaturprofil. Messung der relativen differentiellen Längenänderung nach α/γ-, γ/α- und α/γ/α-Umwandlungen. Einfluβ der Aufheiz- und Abkühlungsgeschwindigkeit und der Vorverformung der Probe auf die irreversible Längenänderung. Beobachtung der Struktur durch thermische Ätzung. Untersuchung der Substruktur durch chemische Ätzung, Laue-Aufnahmen und elekironenoptische Aufnahmen. Zusammenhang zwischen irreversibler Längenänderung und Keimbildung im flachen Teil des Temperaturprofils.     

''I Shot An Arrow in the Air…'' The Performing Arts As Weapons of Social Change

Application of the performing arts as social change agents is illustrated and discussed. Motivations and effectiveness of various groups are exposed and challenged. A review of communication goals and results of the “problem-solving theater” is drawn from recent studies sponsored by the National Council on Crime and Delinquency. Based upon this review, the author poses some characteristics of those enterprises with the greatest promise of effectiveness in the area of resocialization: (1) clients become involved in creative artistic achievement, (2) there are exercises in cooperation and communal activity, (3) there are opportunities for public view and criticism of artistic products, and (4) activities center around adult leadership of stature. The author conclitdes that application of available communication theory calls for programs which change members of “andiences” into participants in meaningful experience.     

Recording human evoked potentials that follow the pitch contour of a natural vowel

We investigated whether pitch-synchronous neural activity could be recorded in humans, with a natural vowel and a vowel in which the fundamental frequency was suppressed. Small variations of speech periodicity were detected in the evoked responses using a fine structure spectrograph (FSS). A significant response (P < 0.001) was measured in all seven normal subjects even when the fundamental frequency was suppressed, and it very accurately tracked the acoustic pitch contour (normalized mean absolute error < 0.57%). Small variations in speech periodicity, which humans can detect, are therefore available to the perceptual system as pitch-synchronous neural firing. These findings suggest that the measurement of pitch-evoked responses may be a viable tool for objective speech audiometry.