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  • optics
  • The electron optics of an SEM or EPMA allow much higher resolution images to be obtained than can be seen using visible-light optics, so features that are irresolvable under a light microscope can be readily imaged to study detailed microtextures or provide the fine-scale context of an individual spot analysis. (carleton.edu)
  • this comprises the electron optics and operates in an analogous way to light optics. (carleton.edu)
  • Samples
  • An electron probe micro-analyzer is a microbeam instrument used primarily for the in situ non-destructive chemical analysis of minute solid samples. (carleton.edu)
  • vacuum
  • A typical arrangement in a probe lab is a vertical electron-beam column, an array of detectors placed around the sample chamber block, a sample entry vacuum lock, a console to control operating conditions, screens to view control interfaces and sample output, and a computer for control of data acquisition. (carleton.edu)
  • orbit
  • when an inner-shell electron is ejected from its orbit, leaving a vacancy, a higher-shell electron falls into this vacancy and must shed some energy (as an X-ray) to do so. (carleton.edu)
  • sample
  • A variety of detectors arranged around the sample chamber that are used to collect x-rays and electrons emitted from the sample. (carleton.edu)
  • beam
  • Bremsstrahlung (continuum) radiation is a continuous spectrum of X-rays from zero to the energy of the electron beam, and forms a background in which characteristic X-ray must be considered. (carleton.edu)
  • Where an electron beam impinges on a sample, electron scattering and photon- and X-ray-production develops in a volume (the electron interaction volume) that is dependent on several factors (Figure 2). (carleton.edu)
  • Each of the electron, X-ray and light emissions generated after the impingement of a high-energy electron beam, develops at different depths (volumes) within the sample. (carleton.edu)
  • Smaller and more asymmetric interaction volumes develop in samples tilted relative to the impinging electron beam. (carleton.edu)
  • the E-T detector collects SE2 electrons and provide topographical information, the in-lens detector collects SE1 electrons and provide high resolution surface information, the EsB detector (which is an in lens detector) collects BS electrons at low voltages thus provide composition contrast for all samples including nonconductive or beam sensitive samples, the STEM detector collects transmitted electrons of thin samples (up to 100nm) at 30kV. (weizmann.ac.il)
  • Because of stringent beam requirement single-shot, 100 fs electron microscopy is completely impossible. (tue.nl)
  • Electron diffraction, however, is much less demanding, requiring much less charge for recording a high-quality diffraction patter and only a modest beam quality. (tue.nl)
  • The ultracold electron source should enable a dramatic increase in beam brightness, which possibly may lead to single-shot, femtosecond diffractive imaging, which up to now is the exclusive domain of the X-ray Free Electron Laser. (tue.nl)
  • The intense electron beam of the microscope will cause radiation damage to the sample, and the miscroscopist must take great care not to fry the sample to death before collecting the desired images. (everything2.com)
  • The resolution depends on the density of the electron beam, the number of images averaged in the reconstruction and sample quality. (everything2.com)
  • Electron microscopy is a technique that uses a beam of accelerated electrons to illuminate and produce images of specimens. (news-medical.net)
  • A transmission electron microscope produces an image by passing a high voltage electron beam through a very thin specimen that is semi-transparent to electrons. (news-medical.net)
  • Similarly to transmission electron microscopy, samples need to be very thin as the technique mainly involves looking at the electron beam transmitted through and emerging from the specimen. (news-medical.net)
  • Information on Electron Beam CT Scanning that can detect coronary artery disease in its earliest, most treatable stages. (dmoztools.net)
  • Particle
  • Due to the nature of the transmission electron microscope, information about internal structure of the particle is contained in the projection. (everything2.com)
  • The electron is a subatomic particle, symbol e− or β− , whose electric charge is negative one elementary charge. (wikipedia.org)
  • Electrons belong to the first generation of the lepton particle family, and are generally thought to be elementary particles because they have no known components or substructure. (wikipedia.org)
  • Irish physicist George Johnstone Stoney named this charge 'electron' in 1891, and J. J. Thomson and his team of British physicists identified it as a particle in 1897. (wikipedia.org)
  • photons
  • the E-T detector collects SE2 electrons and provide topographical information, the in-lens detector collects SE1 electrons and provide high resolution surface information, the AsB detector collects BS electrons at voltages higher than 5kV and provide composition and channeling contrast, the CL detector collects photons that can be emitted as a result of electron-hole recombination in semiconductor samples, the EDS collects x-ray signals and provide elemental analysis. (weizmann.ac.il)
  • Electrons radiate or absorb energy in the form of photons when they are accelerated. (wikipedia.org)
  • When an electron collides with a positron, both particles can be totally annihilated, producing gamma ray photons. (wikipedia.org)
  • metals
  • Samples are prepared by methods similar to that in transmission electron microscopy ( TEM ), typically by fixing the sample with aldehyde, staining with heavy metals such as osmium and uranium then embedding in an epoxy resin. (wikipedia.org)
  • Delocalized electrons also exist in the structure of solid metals. (wikipedia.org)
  • Polyhedral skeletal electron pair theory for cluster compounds , including transition metals and main group elements such as boron including Wade's rules for polyhedral cluster compounds, including transition metals and main group elements and mixtures thereof. (princeton.edu)
  • biological
  • More recently, the application of scanning electron microscopy in the biological sciences has enjoyed something of a renaissance, in part because of recent advances in EM technology. (sciencemag.org)
  • mainly
  • the new generation E-T detector can filter out SE3 electrons, thus it collects mainly SE2 electrons and provide topographical information, the in-lens Duo detector collects SE1 and BS electrons and provide high resolution surface information together with material information, the HD-AsB provides material and orientational information. (weizmann.ac.il)
  • energy
  • There are countless specialized techniques in the field of electron and light microscopy that require the acquisition of specialized knowledge, particularly for interpretation of results (electron tomography and energy dispersive spectroscopy immediately come to mind), but most laboratories possessing the equipment to effect these approaches have specialists to help the casual user. (springer.com)
  • Electrons can be created through beta decay of radioactive isotopes and in high-energy collisions, for instance when cosmic rays enter the atmosphere. (wikipedia.org)
  • transmission
  • Our approach employs standard transmission electron microscopy , rapid automated data collection, and s. (neatorama.com)
  • An electron microscopy technique, where the sample is rapidly cooled to a cryogenic temperature before imaging using a transmission electron microscope . (everything2.com)
  • Scanning transmission electron microscopy combines the technology of both the scanning electron microscope and the transmission electron microscope and can be performed using either piece of equipment. (news-medical.net)
  • generation
  • Each of the signals used for imaging or X-ray generation is generated from different electron interaction volumes and, in turn, each of the signals has different imaging or analytical resolution. (carleton.edu)
  • structure
  • Metallic structure consists of aligned positive ions ( cations ) in a "sea" of delocalized electrons. (wikipedia.org)
  • This means that the electrons are free to move throughout the structure, and gives rise to properties such as conductivity . (wikipedia.org)