发布求助
文献互助 智能选刊 最新文献

Journal of Scientific Instruments最新文献

筛选
英文 中文
A simple ionic flowmeter for measuring very small rates of flow of air. 一种简单的离子流量计，用于测量非常小的空气流速。
Journal of Scientific Instruments Pub Date : 1968-06-01 DOI: 10.1088/0022-3735/1/6/309
W M Jones, D Maidment, D V Morgan
{"title":"A simple ionic flowmeter for measuring very small rates of flow of air.","authors":"W M Jones, D Maidment, D V Morgan","doi":"10.1088/0022-3735/1/6/309","DOIUrl":"https://doi.org/10.1088/0022-3735/1/6/309","url":null,"abstract":"A prototype direct-reading ionic flowmeter to measure rates of flow of air as low as 0·37 μg S−1 has been constructed. The flowmeter functions best at a pressure of 15 torr. A discharge is struck in the air and the discharge current is fixed at about 50 μA. Two ionization chambers are placed symmetrically in a Perspex tube, one on either side of the discharge. Currents through the ionization chambers are arranged in opposition so that there is a null reading on a Vibron electrometer when there is no air flow. When flow of air does occur some ions are carried out of the upstream ionization chamber while some ions are carried into the downstream chamber; the consequent differential current in the electrometer is about 2 pA when the flow is 0·37 μg s−1. The differential current increases linearly with the rate of flow of air at 6 μA (g s−1)−1 up to rates of flow of about 10 μg s−1; thereafter the relationship between differential current and rate of flow departs from linearity, reaching a maximum at a rate of flow of around 0·1 mg s−1. The behaviour of the flowmeter may best be described by regarding the ions as diffusing from the discharge (without recombination) to the ionization chambers.","PeriodicalId":16983,"journal":{"name":"Journal of Scientific Instruments","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1968-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1088/0022-3735/1/6/309","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"16735647","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: 4
A high-power, untuned radio-frequency transmitter for pulsed nuclear magnetic resonance spectroscopy. 一种用于脉冲核磁共振光谱的大功率、非调谐射频发射机。
Journal of Scientific Instruments Pub Date : 1968-06-01 DOI: 10.1088/0022-3735/1/6/304
I J Lowe, C E Tarr
{"title":"A high-power, untuned radio-frequency transmitter for pulsed nuclear magnetic resonance spectroscopy.","authors":"I J Lowe, C E Tarr","doi":"10.1088/0022-3735/1/6/304","DOIUrl":"https://doi.org/10.1088/0022-3735/1/6/304","url":null,"abstract":"A gated radio-frequency transmitter suitable for pulsed nuclear magnetic resonance spectroscopy is described. It has a wide frequency response (3 dB from about 20-50 MHz) and can deliver pulses of greater than 900 v peak to peak into 180 Ω resistive loads with rise and fall times of less than 01 μs. The circuitry described includes a gated radio-frequency mixer-amplifier with two variable phase inputs, and a gated radio-frequency power amplifier. The gating circuits used are d.c. coupled throughout to prevent droop in long pulses and interaction between the pulses.","PeriodicalId":16983,"journal":{"name":"Journal of Scientific Instruments","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1968-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1088/0022-3735/1/6/304","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"16735979","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: 19
Performance of a high sensitivity liquid scintillation whole-body counter. 高灵敏度液体闪烁全身计数器的性能。
Journal of Scientific Instruments Pub Date : 1968-06-01
D H Pringle, C F Barnaby
{"title":"Performance of a high sensitivity liquid scintillation whole-body counter.","authors":"D H Pringle, C F Barnaby","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":16983,"journal":{"name":"Journal of Scientific Instruments","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1968-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"16735653","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: 0
An improved form of mercury manometer. 一种改进的水银压力计。
Journal of Scientific Instruments Pub Date : 1968-06-01 DOI: 10.1088/0022-3735/1/6/443
F Akerboom, H H Van Mal
{"title":"An improved form of mercury manometer.","authors":"F Akerboom, H H Van Mal","doi":"10.1088/0022-3735/1/6/443","DOIUrl":"https://doi.org/10.1088/0022-3735/1/6/443","url":null,"abstract":"A description is given of a form of mercury manometer which has the measurement arms in line with each other, has a very rigid construction and yet a loss in working range of only 3?5 cm. Where a cathetometer is used and where a large number of accurate readings must be made, such an instrument can save time and effort and can diminish sources of error.","PeriodicalId":16983,"journal":{"name":"Journal of Scientific Instruments","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1968-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1088/0022-3735/1/6/443","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"16735654","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: 5
A device for the control of particle size in the La Mer aerosol generator. La Mer气溶胶发生器中控制颗粒大小的装置。
Journal of Scientific Instruments Pub Date : 1968-06-01 DOI: 10.1088/0022-3735/1/6/312
J Edwards, B J Brinkworth
{"title":"A device for the control of particle size in the La Mer aerosol generator.","authors":"J Edwards, B J Brinkworth","doi":"10.1088/0022-3735/1/6/312","DOIUrl":"https://doi.org/10.1088/0022-3735/1/6/312","url":null,"abstract":"A description is given of a device which provides automatic long-term control of the size of aerosol particles produced by the La Mer generator. The control system input signal is derived from the light-scattering properties of the outgoing particles. Over periods of eight hours, variations in mean size are found to be typically less than 10% for aerosols with particle diameters of about 1 μm.","PeriodicalId":16983,"journal":{"name":"Journal of Scientific Instruments","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1968-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1088/0022-3735/1/6/312","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"16735649","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: 6
Spectrograph design, 1918-68. 摄谱仪设计，1918- 1968。
Journal of Scientific Instruments Pub Date : 1968-06-01 DOI: 10.1088/0022-3735/1/6/201
R C Learner
{"title":"Spectrograph design, 1918-68.","authors":"R C Learner","doi":"10.1088/0022-3735/1/6/201","DOIUrl":"https://doi.org/10.1088/0022-3735/1/6/201","url":null,"abstract":"This year, 1968, is the 50th anniversary of the formation of the Institute of Physics. (The Institute of Physics and The Physical Society was formed from the amalgamation of the two bodies.) In order to celebrate this Jubilee we are publishing a series of articles concerning various aspects of instrumentation over the last 50 years.","PeriodicalId":16983,"journal":{"name":"Journal of Scientific Instruments","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1968-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1088/0022-3735/1/6/201","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"15964297","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: 11
A laser technique for the measurement of aerosols. 一种测量气溶胶的激光技术。
Journal of Scientific Instruments Pub Date : 1968-06-01 DOI: 10.1088/0022-3735/1/6/311
T D Proctor
{"title":"A laser technique for the measurement of aerosols.","authors":"T D Proctor","doi":"10.1088/0022-3735/1/6/311","DOIUrl":"https://doi.org/10.1088/0022-3735/1/6/311","url":null,"abstract":"The paper describes the use of a continuous-wave helium-neon laser to measure the surface area of small concentrations (< 3000 particles per cm3) of dust particles, of size less than 5 μm, suspended in air. The suspension is passed through a size-selector to remove dust particles greater than 5 μm in size and then into a chamber between one of the laser mirrors and the end of the laser tube. Scattering and absorption of radiation from the cavity by the dust particles causes a change in the amount of radiation reflected back into the laser tube, which in turn produces a reduction in the intensity of the output beam. The relationship between the surface-area concentration of the airborne dust and the change in the output intensity is derived, and experiments with an instrument of this type are described and discussed.","PeriodicalId":16983,"journal":{"name":"Journal of Scientific Instruments","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1968-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1088/0022-3735/1/6/311","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"16735648","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: 9
Field ionization mass spectrometry with a modified MS9 spectrometer. 用改良的MS9谱仪进行场电离质谱分析。
Journal of Scientific Instruments Pub Date : 1968-06-01 DOI: 10.1088/0022-3735/1/6/306
J D Emmerson, B E Job
{"title":"Field ionization mass spectrometry with a modified MS9 spectrometer.","authors":"J D Emmerson,&nbsp;B E Job","doi":"10.1088/0022-3735/1/6/306","DOIUrl":"https://doi.org/10.1088/0022-3735/1/6/306","url":null,"abstract":"Simple mechanical and electrical modifications to the conventional ion source of an MS9 mass spectrometer have permitted its additional use as a field ionization mass spectrometer, while the original electron impact mode of operation is retained. The combined source may be used in either form without any dismantling of the source or the breaking of the vacuum seals.","PeriodicalId":16983,"journal":{"name":"Journal of Scientific Instruments","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1968-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1088/0022-3735/1/6/306","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"16735980","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: 1
An image intensifier for the electron microscope. 电子显微镜的图像增强器。
Journal of Scientific Instruments Pub Date : 1968-06-01 DOI: 10.1088/0022-3735/1/6/303
K Anderson
{"title":"An image intensifier for the electron microscope.","authors":"K Anderson","doi":"10.1088/0022-3735/1/6/303","DOIUrl":"https://doi.org/10.1088/0022-3735/1/6/303","url":null,"abstract":"An image intensifier system using a four-stage image intensifier optically coupled to a phosphor screen in the electron microscope is described. The system is shown to be limited by the quantum noise inherent in the electron image. The system can detect images down to 10 fA cm−2 which is at least an order of magnitude better than can be achieved by a fully dark adapted operator viewing the normal fluorescent screen of the microscope.","PeriodicalId":16983,"journal":{"name":"Journal of Scientific Instruments","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1968-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1088/0022-3735/1/6/303","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"16735978","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: 11
An oil manometer with continuous electrical readout. 具有连续电读数的油压力计。
Journal of Scientific Instruments Pub Date : 1968-06-01 DOI: 10.1088/0022-3735/1/6/319
G Sidenius
{"title":"An oil manometer with continuous electrical readout.","authors":"G Sidenius","doi":"10.1088/0022-3735/1/6/319","DOIUrl":"https://doi.org/10.1088/0022-3735/1/6/319","url":null,"abstract":"The development of an oil manometer with a precise continuous electrical readout of the oil height is described. The principle of measurement is by a hot thin wire partly immersed in the oil. The accuracy of the electrical reading is better than ?0?1 mm of oil, the resolution is better than 0?03 mm of oil and the pressure range can be from 1 mm of oil (about 0?06 torr) up to the practical limit of building oil manometers, about 1000 mm of oil (about 60 torr). It is possible to use the transducer electrode directly as a Pirani gauge with a pressure range from 10?4 to 1 torr. The use of the manometer in a pressure stabilizing system is described.","PeriodicalId":16983,"journal":{"name":"Journal of Scientific Instruments","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1968-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1088/0022-3735/1/6/319","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"16735651","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: 5
首页 上一页 下一页 尾页
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整，为了账户安全，请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
请完成安全验证×
相关产品
×
本文献相关产品
联系我们：info@booksci.cn Book学术提供免费学术资源搜索服务，方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号：481959085
Book学术官方微信