The effect of deformation-zone geometry on split-ends formation in plane-strain rolling

Mechanism and model is proposed for split-ends defects formation in plane-strain rolling. An upper bound method has been chosen for this analysis and a rigid body uni-triangular rotational velocity field was assumed for the deformation zone. Two solutions were obtained for rolling process; for sound flow and split-ends pattern. By comparing power requirements for these cases, the whole range of rolling parameters has been divided into safe and split-ends zone. Both perfectly plastic and strain-hardening materials are studied. It has been found that split-ends formation (crocodiling) is more likely to occur in thick plates and sheets when slight reduction is applied. Comparison of analytically developed criteria with data from experimental rolling of aluminium specimens shows generally good agreement.     

Mössbauer resonance studies on the Ca2Fe2O5-LaFeO3 system

Phases between Ca₂Fe₂O₅ and LaFeO₃ with La_1?2yCa_2yFe³⁺O_3?y formulation have been prepared in order to study the oxygen defects in perovskite-related ferrites. X-ray-diffraction analysis and magnetic measurements have confirmed the previous results i.e. the existence of a critical concentration of vacancies above which long range ordering appears. A detailed Mössbauer resonance study shows a continuous evolution of the iron environment, tetrahedra being formed even for low values of y. This result has been discussed and compared with previous ones for homologous CaTi_1?2yFe_2yO_?y phases.     

Excited triplet states in bituminous coal

The intensities of the broad and narrow lines constituting the e.p.r. spectrum of coal depend on the temperature of measurement. The system of paramagnetic centres related to the broad line does not obey the Curie law and consists of free radicals ($\text{S =}\text{1}\text{2}$) and of centres with singlet ground state (S = 0) and lowest-excited triplet state (S = 1). The singlet-triplet excitation energy, J, is comparable with thermal energy, kT, of lattice vibrations. The system of paramagnetic centres related to the narrow line obeys the Curie law ($\text{S =}\text{1}\text{2}$).     

Analytical function for lidar geometrical compression form-factor calculations

A simple model of image formation in a Newtonian telescope was used for calculating an analytical formula, that describes the geometric compression form factors of coaxial and biaxial lidars. Calculations were successfully validated by comparison with real measurements, confirming the accuracy of our approach. The need for different alignment of coaxial and biaxial systems to increase the overlap between the lidar emitter and receiver is also discussed.     

Cyclic voltammetric studies on a monocrystalline antimony electrode

Monocrystalline antimony electrodes have been studied by cyclic voltammetry in solutions containing sodium nitrate and one of the following complexing agents: TRIS [Tris (hydroxymethyl) amino methane], orthophosphate, EDTA (ethylenedinitrilo tetraacetic acid) or tartrate at an ionic strength of 0.16 The results have been compared to results obtained in a solution containing only sodium nitrate, which has been shown previously to have no effect on the Sb-electrode potential in the pH range 2–10 which was studied.The results indicate formation of soluble complexes with the ligands studied. Competing reactions seem to take place in the solutions containing orthophosphate (and presumably EDTA). The reactions between Sb(III) and TRIS or orthophosphate seem to be reversible for all practical purposes.The complex formation between Sb(III) and TRIS seems to be weak since the behaviour of the electrode is very similar in TRIS and in pure nitrate solution. TRIS is therefore suitable as a buffer for calibrating antimony electrodes.     

Über die eigenschaften von selbstverlöschenden polyarylestern aus aromatischen dicarbonsäuren und 2,2-bis(4-hydroxyphenyl)-1,1-dichloräthylen

The mechanical, thermomechanical, electrical and some other properties of polyarylates derived from chloro-bisphenol derivates of chloral and phenol, especially from 2,2-bis(4-hydroxyphenyl)-1,1-dichloroethylene and a mixture of tere- and isophthalic acid dichloride (2:1), were examined.     

Applicability and limitations in the use of national input-output tables for regional studies

Some Tentative Conclusions It appears that although national input-output tables cannot be used for purposes of regional studies without considerable adjustments, acceptable results can be achieved by the methods tried on the Washington State table.In order to obtain acceptable results it seems important (1) to exclude the tertiary sectors through aggregation, and (2) to use field surveys in order to obtain input-output coefficients for (a) primary industries and (b) industries in which the regional economy is specialized. Price adjustments and adjustments for domestic imports do not seem to add anything to the quality of results. Neither do successive iterations after the first one.Financial help for this research was provided by a Cornell Faculty Research Grant to the senior author and is acknowledged. The authors are deeply indebted to the late Professor Charles M. Tiebout, of the University of Washington, who provided the Washington State Input-Output Table used for the case study and who also assisted with helpful comments. Mrs. Katherine Drew and Mrs. Tessa Osborne gave programming assistance, and Barry Lawson acted as research assistant during part of the preparation.