摘要:

Cu‐30 Vol % Fe multifilamentary composites were producedinsitu. Magnetic hysteresis loops of wire and tape composites were obtained at room temperature as a function of both cross‐sectional area reduction, up to 99.9996%, and annealing conditions.Hciand (BH)maxincrease with cross‐sectional area reduction, reaching 250 Oe and 0.46 MG Oe, respectively, in the most heavily deformed unannealed samples. On proper annealing,Hciand (BH)maxincrease dramatically, up to 590 Oe and 1.35 MG Oe, respectively. Considering the simple preparation technique and inexpensive constituent elements, theinsituformed Cu‐Fe composites appear to have the potential for permanent magnet applications.

ISSN:0003-6951    

DOI:10.1063/1.92810

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

Recombination luminescence has been observed in particle dispersions of an organic photoconductor (x‐H2Pc) by a new electro‐optical technique that eliminates the need for double injection electrodes. The method permits independent investigations to be made of the charge carrier photogeneration and recombination processes in a single sample of photoconducting material.

ISSN:0003-6951    

DOI:10.1063/1.92811

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

The reduction of V ions in FeV3O8from V5+(3d0) and V4+(3d1) to V4+(3d1) and V3+(3d2) by lithiation withn‐BuLi has been inferred by57Fe Mo¨ssbauer effect. The Fe is localized and in the Fe3+state for allx.

ISSN:0003-6951    

DOI:10.1063/1.92812

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

A small concentration of thin plate‐like insulating material in a conducting host can give rise to anomalously high values of dielectric constant. For a small concentration &eegr; of oblate spheroidal grains (a ≪ b=c) with depolarization factor along symmetry (a) axisLs= 1−&dgr;,&dgr; = &pgr;a/2b, the static value of the dielectric constant of rock &egr;sand dc conductivity &sgr;(0) are given for (a) &dgr;<&eegr; as &sgr;(0) = &dgr;&sgr;R/&eegr;, &egr;s≅&egr;m/&eegr;, and for (b) &dgr;≳&eegr; as &sgr;(0)≅&sgr;R(1−&eegr;/&dgr;), &egr;s≅&eegr;&egr;m/&dgr;2. Case (a) corresponds to the well‐known Maxwell–Wagner effect with &egr;sdiverging as &eegr;→0, and &sgr;(0)→0. Case (b) gives a novel result that &egr;smay diverge for &dgr;≳&eegr;≫&dgr;2, with a nonvanishing &sgr;(0). Case (b) is applied to explain frequency and salinity dependences and the large values (∼103, observed at MHz frequencies) of the dielectric constant of conducting sedimentary rocks. Possible reasons for the larger values (∼106) observed experimentally at lower (khz) frequencies are discussed.

ISSN:0003-6951    

DOI:10.1063/1.92813

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

The interdiffusion mechanism governing the leaching (or hydration) of glasses is studied using the19F resonant nuclear reaction. By measuring the number of hydrogen ions in the surface layers of leached glasses, we have identified that a hydronium‐sodium ion exchange process is in operation in leached commercial glasses while it is less conclusive as to the exact mechanism responsible for the leaching of simple laboratory binary and ternary glasses.

ISSN:0003-6951    

DOI:10.1063/1.92814

出版商:AIP    

年代:1981

数据来源: AIP

ISSN:0003-6951    

DOI:10.1063/1.92888

出版商:AIP    

年代:1981

数据来源: AIP

ISSN:0003-6951    

DOI:10.1063/1.92890

出版商:AIP    

年代:1981

数据来源: AIP