Biomaterial Database

Mass determination of thin biological specimens for use in quantitative electron probe X-ray microanalysis. 1982

P W Linders, and A L Stols, and R A van de Vorstenbosch, and A M Stadhouders

In the quantitative electron probe X-ray microanalysis of thin specimens the total mass thickness of a specimen is often required to express the elemental content as fractions of the total mass. In the present paper three methods for the measurement of mass thickness of thin specimens are reviewed and compared as to their applicability for use in quantitative X-ray microanalysis. The methods are based on the use of the continuum X-ray intensity, the backscattered electron intensity, and the transmitted electron intensity, respectively. From experimental results, it is concluded that the mass measurement method, based on the transmitted electron intensity, gives more accurate mass values than does the continuum X-ray method. The use of an independent mass measurement method is advantageous when low temperature oxygen plasma ashing is applied to lower X-ray analysis detection limits. In this way, elements present in ashed specimens can be expressed as fractions of the original specimen mass.

UI	MeSH Term	Description	Entries
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D008855	Microscopy, Electron, Scanning	Microscopy in which the object is examined directly by an electron beam scanning the specimen point-by-point. The image is constructed by detecting the products of specimen interactions that are projected above the plane of the sample, such as backscattered electrons. Although SCANNING TRANSMISSION ELECTRON MICROSCOPY also scans the specimen point by point with the electron beam, the image is constructed by detecting the electrons, or their interaction products that are transmitted through the sample plane, so that is a form of TRANSMISSION ELECTRON MICROSCOPY.	Scanning Electron Microscopy,Electron Scanning Microscopy,Electron Microscopies, Scanning,Electron Microscopy, Scanning,Electron Scanning Microscopies,Microscopies, Electron Scanning,Microscopies, Scanning Electron,Microscopy, Electron Scanning,Microscopy, Scanning Electron,Scanning Electron Microscopies,Scanning Microscopies, Electron,Scanning Microscopy, Electron
D002122	Calcium Chloride	A salt used to replenish calcium levels, as an acid-producing diuretic, and as an antidote for magnesium poisoning.	Calcium Chloride Dihydrate,Calcium Chloride, Anhydrous
D004577	Electron Probe Microanalysis	Identification and measurement of ELEMENTS and their location based on the fact that X-RAYS emitted by an element excited by an electron beam have a wavelength characteristic of that element and an intensity related to its concentration. It is performed with an electron microscope fitted with an x-ray spectrometer, in scanning or transmission mode.	Microscopy, Electron, X-Ray Microanalysis,Spectrometry, X-Ray Emission, Electron Microscopic,Spectrometry, X-Ray Emission, Electron Probe,X-Ray Emission Spectrometry, Electron Microscopic,X-Ray Emission Spectrometry, Electron Probe,X-Ray Microanalysis, Electron Microscopic,X-Ray Microanalysis, Electron Probe,Microanalysis, Electron Probe,Spectrometry, X Ray Emission, Electron Microscopic,Spectrometry, X Ray Emission, Electron Probe,X Ray Emission Spectrometry, Electron Microscopic,X Ray Emission Spectrometry, Electron Probe,X-Ray Microanalysis,Electron Probe Microanalyses,Microanalyses, Electron Probe,Microanalysis, X-Ray,Probe Microanalyses, Electron,Probe Microanalysis, Electron,X Ray Microanalysis,X Ray Microanalysis, Electron Microscopic,X Ray Microanalysis, Electron Probe
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D014961	X-Ray Diffraction	The scattering of x-rays by matter, especially crystals, with accompanying variation in intensity due to interference effects. Analysis of the crystal structure of materials is performed by passing x-rays through them and registering the diffraction image of the rays (CRYSTALLOGRAPHY, X-RAY). (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Xray Diffraction,Diffraction, X-Ray,Diffraction, Xray,Diffractions, X-Ray,Diffractions, Xray,X Ray Diffraction,X-Ray Diffractions,Xray Diffractions