British Journal of Applied Physics最新文献_第9页

The multiple emission of electrons in a secondary-electron particle counter 二次电子粒子计数器中电子的多次发射

British Journal of Applied Physics Pub Date : 1967-08-01 DOI: 10.1088/0508-3443/18/8/312

L. E. Collins, P. Stroud

引用次数: 12

The mechanism of the electrical breakdown of air in uniform fields at voltages up to 400 kv 电压达400千伏的均匀电场中空气电击穿的机理

British Journal of Applied Physics Pub Date : 1967-08-01 DOI: 10.1088/0508-3443/18/8/311

J. Dutton, W. T. Morris

{"title":"The mechanism of the electrical breakdown of air in uniform fields at voltages up to 400 kv","authors":"J. Dutton, W. T. Morris","doi":"10.1088/0508-3443/18/8/311","DOIUrl":"https://doi.org/10.1088/0508-3443/18/8/311","url":null,"abstract":"Measurements of pre-breakdown ionization currents in uniform fields in dry air at pressures of about 1600 torr were carried out over a range of voltages from 165 kv to over 400 kv, corresponding to a range of values of the parameter p20d (p20 is the pressure reduced to 20°c and d is the electrode separation) from 500 to 12 600 torr cm. Over the whole range investigated the spatial growth of ionization was found to be in accordance with the well-known generalized Townsend equation. Moreover, at a value of p20ds of 12 200 torr cm (ds is the sparking distance), the sparking potential of 408 ± 9 kv predicted by using the Townsend breakdown criterion was in good agreement with the experimentally measured value of 4034 ± 05 kv. In these experiments the gas pressure and electrode separation were chosen so that the maximum value of the field used was less than about 60 kv cm-1. At this value field emission was negligible compared with the externally generated initial current I0 (similar 10-12 A), and values of I0 of this magnitude were shown, experimentally, not to give rise to significant space-charge effects in the measurement of pre-breakdown ionization. The values of the secondary ionization coefficient ω/ά were found to be markedly dependent on the state of the cathode surface showing that, just as at lower pressures and voltages, the cathode plays an important role in the breakdown process. At higher pressures (similar 5000 torr) and higher pre-breakdown fields (similar 100 kv cm-1) field emission currents of about 10-10 A were observed, which can be accounted for on the basis of the Fowler-Nordheim equation modified to take account of the presence of a thin insulating surface film: this work is currently being extended to the investigation of breakdown in these conditions, when space-charge distortion of the applied field due to high field emission from small cathode areas may become important.","PeriodicalId":9350,"journal":{"name":"British Journal of Applied Physics","volume":"206 1","pages":"1115-1120"},"PeriodicalIF":0.0,"publicationDate":"1967-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89322396","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 20

The cold drawing of polyethylene terephthalate 聚对苯二甲酸乙二醇酯的冷拔

British Journal of Applied Physics Pub Date : 1967-08-01 DOI: 10.1088/0508-3443/18/8/316

S. W. Allison, I. Ward

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引用次数: 109

Theory of the wall effect in the viscosity of suspensions 悬浮液粘度的壁效应理论

British Journal of Applied Physics Pub Date : 1967-08-01 DOI: 10.1088/0508-3443/18/8/319

A. Maude

引用次数: 5

Some characteristics of the ammonia maser amplifier 氨激射放大器的一些特性

British Journal of Applied Physics Pub Date : 1967-08-01 DOI: 10.1088/0508-3443/18/8/303

R. Collier, T. Wilmshurst

引用次数: 2

The annealing of quenched-in vacancies in dilute aluminium alloys 稀铝合金中淬火空位的退火

British Journal of Applied Physics Pub Date : 1967-08-01 DOI: 10.1088/0508-3443/18/8/306

F. C. Dockworth, J. Burke

引用次数: 8

RESEARCH NOTES: Changes produced in thermoelectric materials by thermal-neutron irradiation 研究笔记:热中子辐照对热电材料产生的变化

British Journal of Applied Physics Pub Date : 1967-08-01 DOI: 10.1088/0508-3443/18/8/422

M. Idnurm, K. Landecker

引用次数: 9

The relationship between thermally stimulated luminescence and thermally stimulated conductivity 热激发光与热激电导率的关系

British Journal of Applied Physics Pub Date : 1967-08-01 DOI: 10.1088/0508-3443/18/8/127

I. Saunders

引用次数: 23

ELECTRON RECOMBINATION AND THERMIONIC EMISSION IN NEGATIVELY CHARGED SOLID PARTICLES. 负电荷固体粒子中的电子复合和热离子发射。

British Journal of Applied Physics Pub Date : 1967-08-01 DOI: 10.1088/0508-3443/18/8/313

M. Sodha, S. Sharma

引用次数: 9

Thermomagnetic figures of merit of bismuth at 77°K 铋在77°K时的热磁特性图

British Journal of Applied Physics Pub Date : 1967-08-01 DOI: 10.1088/0508-3443/18/8/305

D. Ballentyne, D. Lacklison

引用次数: 0