IL23192A - Method of stabilization of thermionic sources and thermionic source obtained by application of said method or a like method - Google Patents

Method of stabilization of thermionic sources and thermionic source obtained by application of said method or a like method

Info

Publication number
IL23192A
IL23192A IL23192A IL2319265A IL23192A IL 23192 A IL23192 A IL 23192A IL 23192 A IL23192 A IL 23192A IL 2319265 A IL2319265 A IL 2319265A IL 23192 A IL23192 A IL 23192A
Authority
IL
Israel
Prior art keywords
filament
substance
thermionic
stabilization
layer
Prior art date
Application number
IL23192A
Other languages
Hebrew (he)
Original Assignee
Commissariat Energie Atomique
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Commissariat Energie Atomique filed Critical Commissariat Energie Atomique
Publication of IL23192A publication Critical patent/IL23192A/en

Links

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F1/00—Details of amplifiers with only discharge tubes, only semiconductor devices or only unspecified devices as amplifying elements
    • H03F1/52—Circuit arrangements for protecting such amplifiers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J27/00—Ion beam tubes
    • H01J27/02—Ion sources; Ion guns
    • H01J27/26—Ion sources; Ion guns using surface ionisation, e.g. field effect ion sources, thermionic ion sources
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J49/00—Particle spectrometers or separator tubes
    • H01J49/02—Details
    • H01J49/10—Ion sources; Ion guns
    • H01J49/16—Ion sources; Ion guns using surface ionisation, e.g. field-, thermionic- or photo-emission
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F3/00—Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements
    • H03F3/04—Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements with semiconductor devices only
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
    • Y10T428/2913—Rod, strand, filament or fiber
    • Y10T428/2933—Coated or with bond, impregnation or core
    • Y10T428/294—Coated or with bond, impregnation or core including metal or compound thereof [excluding glass, ceramic and asbestos]
    • Y10T428/2942—Plural coatings
    • Y10T428/2949—Glass, ceramic or metal oxide in coating

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Plasma & Fusion (AREA)
  • Analytical Chemistry (AREA)
  • Combustion & Propulsion (AREA)
  • Other Investigation Or Analysis Of Materials By Electrical Means (AREA)
  • Sampling And Sample Adjustment (AREA)

Description

τπηιι fro ΤΪΙΠΓ·Ί ·π PATENT ATTORNEYS · Q'QIQS 'DUD PATENTS AND DESIGNS ORDINANCE SPECIFICATION Method of stabilization of thermionic sources and thermionic source obtained by application of said method or a like method mm riB»©a ntt IT n©"»©a ©ia© »ny Vapnan I (we) COMMISSARIAT A I·EMERGES ATOHIQUE, of 29, rue de la Federation, Paris XV° - (Seine) France do hereby declare the nature of this invention and in what manner the same is to be performed, to be particularly described and ascertained in and by the following statement:- 231922 <* Shis invention la concerned with a method of stabilisation of a thermionic source designed for use in mass spectrometry.
When a solid thermionic source is employed for the purpose of performing an analysis by mass spectrometry* there always takes place a rapid decrease in the ion current as a result of the evaporation of the sample being studied. $hls decrease makes it more difficult to interpret the diagrams than in the case of utilisation of a gas source in which suc a phenomenon is not perceptible. For this reason, it has appeared advantageous to reduce this process of ion current decrease by means of an effect whic would prevent evaporation by overheating of the sample to be analysed.
To this end, the invention has for its object a method of stabilisation of a thermionic source which can be utilised in mass spectrometry and which makes it possible to obtain a constant thermionic emission. he method in accordance with the invention consists in depositing on a metallic filament which serves as a heating source a layer of substance which is capable of providing as a result of heating a uniform layer having a smooth surface and poor thermal conductivity, in effecting the slow calcination of the filament which is coated with said substance until there is ormed a layer which efectively adheres to the ilament, in charging the aggregate thus obtained with a mixture consisting of said substance and of the product to be analysed by mass spectrometry and in calcining the aggregate.
She thermionic source as thus prepared can be employed for the purpose of performing an analysis by mass spectrometry? said souroe consists of a heating filament which is coated with w is in turn coated with a layer of a mixture of the stabilizing substance and of the substance to be analyzed.
The, stabilizer must be refractory and have poor thermal conductivity in order to withstand without melting the high temperatures to which the filament is brought at the time of heating. The stabilizer must be such that, after it has been applied on the filament and after said filament has been heated, said stabilizer is present in s uniform layer having a smooth surface . The stabilizing substance thus prepared is essentially intended for temperature stabilization.
Among the products which meet the foregoing conditions, there can be mentioned by way of example the following substances which can be employed either separately or in combination : Titanium pyrophosphate Ti P2 Magnesium aluminate Mg AI2 O4.
Nickel oxide NiO A large number of other metal salts are also suitable for the practical application of the invention.
It is merely necessary to ensure that such salts meet the following conditions : they must be refractory, they must have poor thermal conductivity and they must provide, once they have been applied on the filament and heated, a uniform layer having a smooth surface . There can be mentioned by way of example the salts of calcium, strontium, barium, zirconium, thorium and hafnium.
One non-limitative example of application of the method in accordance with the invention to the preparation of a stabilized thermionic source will now be described.
The metallic heating filament consists of a metal which has platinum, rhenium or tungsten.
The stabilizer is prepared in the form of gel and is deposited on the filament by means of a platinum spatula; the aggregate is then subjected to a first calcining treatment by sending an electric current through the filament, thus increasing its temperature by Joule effect. The heating must be performed with care in such a manner as to ensure that the layer of stabilizing substance effectively adheres to the filament after calcination.
The filament which is thus covered with stabilizer is then charged with a layer of stabilizing substance which is mixed with the product to be analyzed.
The quantities employed must be small since it would prove undesirable, to overcharge the filament. The calcination is then performed under the same conditions as before . When these different operations have been completed, the filament appears in the form of a thin layer of stabilizer which adheres to the metal in a perfect manner and the thickness of which can vary between 0.2 and 1 mm but is preferably equal to 0.5 m . Under the microscope, the surface of said layer is of uniform appearance although not glass-like.
One preferred method of operation of the source in accordance with the invention will now be described in the case in which the said source as thus prepared is employed for the purpose of performing an isotopic analysis by mass spectrometry. The filament which is prepared in the manner which has been described above is fitted in the source of. the spectrometer, then heated very progressively until the vacuum of the source is restored. Rapid heating is harmful since it is liable to result in separation of filament .
As soon as the vacuum of the source has been brought to a correct value, the appearance of the mass spectrum is studied and there are first of all observed the impurities which are contained in the stabilizer and which can be rapidly caused to disappear by a slight increase in temperature. The masses corresponding to the elements of the product to be analyzed then appear and the emission can be very easily regulated.
The source then remains stable throughout the analysis (this latter canlast several hours) without any appreciable decrease in the ion current.
A thermionic source in accordance with the invention has the great advantage, in particular when performing an analysis by mass spectrometry, in that the product to be analyzed can be utilized in solid form, thus requiring only a minimum number of manipulations. Moreover, a source of this kind makes it possible to perform isotopic analyses of long duration without any fluctuations which are higher than those produced by a gas source. 23192/2

Claims (3)

1. Method of stabilization of a thermionic source designed for use in mass spectrometry, characterized in that it consists in depositing on a metallic filament a layer of refractory substance which is intended to provide as a result of heating a uniform coating having a smooth surface and poor thermal conductivity, in effecting the slow calcination of the filament which is coated with said substance until there is formed a layer which effectively adheres to the filament, in charging the aggregate thus obtained with a mixture consisting of said substance and of the product to be analysed by mass spectrometry and in calcining the aggregate*
2. · Method of stabilization of a thermionic source in accordance with Claim 1, characterized in that said substance can be chosen from the group consisting of titanium pyrophosphate, magnesium aluminate and nickel oxide.
3. thermionic source designed for use in mass spectrometry, characterized in that said source consists of a heating filament of a conductive substance having a high melting point, a layer of refractory substance having a uniform surface which covers the filament and which has poor thermal conductivity, and an outer layer containing a mixture of the product to be analyzed and of said substance. For the Applicants 3S
IL23192A 1964-03-27 1965-03-22 Method of stabilization of thermionic sources and thermionic source obtained by application of said method or a like method IL23192A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR968985A FR1398135A (en) 1964-03-27 1964-03-27 Process for stabilizing thermionic sources and thermionic source in accordance with those obtained by applying said process or a similar process

Publications (1)

Publication Number Publication Date
IL23192A true IL23192A (en) 1968-07-25

Family

ID=8826561

Family Applications (1)

Application Number Title Priority Date Filing Date
IL23192A IL23192A (en) 1964-03-27 1965-03-22 Method of stabilization of thermionic sources and thermionic source obtained by application of said method or a like method

Country Status (9)

Country Link
US (1) US3423583A (en)
BE (1) BE661230A (en)
CH (1) CH432054A (en)
DE (1) DE1297899B (en)
FR (1) FR1398135A (en)
GB (1) GB1088268A (en)
IL (1) IL23192A (en)
LU (1) LU48259A1 (en)
NL (1) NL6503985A (en)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2011063086A1 (en) 2009-11-19 2011-05-26 Halliburton Energy Services, Inc. Downhole optical radiometry tool
CN102334024A (en) 2009-12-23 2012-01-25 哈利伯顿能源服务公司 Interferometry-based downhole analysis tool
MY164684A (en) 2010-06-01 2018-01-30 Halliburton Energy Services Inc Spectroscopic nanosensor logging systems and methods
BR112012013906A2 (en) * 2010-06-16 2016-04-26 Halliburton Energy Services Inc light source
AU2019263158B2 (en) * 2018-04-30 2023-12-14 Leidos, Inc. An improved low-power mass interrogation system and assay for determining vitamin D levels

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2710354A (en) * 1952-08-28 1955-06-07 Mark G Inghram Ion source
US2756341A (en) * 1954-02-15 1956-07-24 Gen Electric Multiple cartridge source for mass spectrometer
NL268393A (en) * 1960-08-19

Also Published As

Publication number Publication date
US3423583A (en) 1969-01-21
CH432054A (en) 1967-03-15
FR1398135A (en) 1965-05-07
NL6503985A (en) 1965-09-28
BE661230A (en) 1965-07-16
DE1297899B (en) 1969-06-19
LU48259A1 (en) 1965-05-25
GB1088268A (en) 1967-10-25

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