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  • NSOM
  • Previously, IR-NSOM was realized by applying a solid immersion lens with a refractive index of n, which shortens wavelength (λ) to (λ/n), compared to FTIR-based IR microscopy. (wikipedia.org)
  • probe
  • cells immobilized in polyacrylamide gel (FAG) were analyzed using scanning transmission electronmicroscopy with electron probe X-ray microanalysis (EPXMA) and proton-induced X-ray emissionanalysis(PIXE). (diva-portal.org)
  • spectroscopy
  • 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)
  • Electron microscopic observation in liquid has been combined with other analytical methods such as electrochemical measurements and energy-dispersive X-ray spectroscopy (EDX). (wikipedia.org)
  • This technique is used to form spectra in Electron energy loss spectroscopy (EELS), but it is also possible to place an adjustable slit to allow only electrons with a certain range of energies through, and reform an image using these electrons on a detector. (wikipedia.org)
  • Ultramicroscopy
  • CS1 maint: Extra text: authors list (link) F. Hofer, P. Warbichler and W. Grogger, Imaging of nanometer-sized precipitates in solids by electron spectroscopic imaging, Ultramicroscopy, Volume 59, Issues 1-4, July 1995, Pages 15-31. (wikipedia.org)
  • LEED
  • Imaging of the back focal plane of the objective lens into the object plane of the projector lens (using an intermediate lens) produces a diffraction pattern (low-energy electron diffraction, LEED) at the imaging plane and recorded in a number of different ways. (wikipedia.org)
  • crystallography
  • Bridget Carragher and colleagues at the Scripps National Resource for Automated Molecular Microscopy used techniques she and Clint Potter developed to create the first cryo-electron microscopy structural biology image with a resolution finer than 3 Ångströms, thereby elevating cryo-EM as a tool comparable to and potentially superior to traditional x-ray crystallography techniques. (wikipedia.org)
  • This technique is called electron crystallography. (wikipedia.org)
  • The technique can be used to aid chemical analysis of the sample in conjunction with complementary techniques such as electron crystallography. (wikipedia.org)
  • generate
  • PEEM utilizes local variations in electron emission to generate image contrast. (wikipedia.org)
  • The research team worked on lens design and CRO column placement, to optimize parameters to construct better CROs, and make electron optical components to generate low magnification (nearly 1:1) images. (wikipedia.org)
  • detector
  • EsB detector with filtering grid for the detection of energy selective backscattered electrons. (weizmann.ac.il)
  • 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)
  • 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)
  • electrostatic
  • In that same year, Reinhold Rudenberg, the scientific director of the Siemens company, patented an electrostatic lens electron microscope. (wikipedia.org)
  • An electrostatic immersion objective lens brings the sample close to that of the gun, slowing down the high energy electrons to a desired energy only just before interacting with the sample surface. (wikipedia.org)
  • Once sufficient thermal vibrational energy is attained electrons may overcome this electrostatic energy barrier, allowing them to travel into vacuum and accelerate down the lens column to the gun potential (because the lenses are at ground). (wikipedia.org)
  • Nano
  • This technique is used in order to obtain information at different length scales: the electron microscope provides high-resolution information down to the nano-scale, while the fluorescence microscope highlights the regions of interest. (wikipedia.org)
  • The electron microscope is used to obtain structural information at the nano-scale. (wikipedia.org)
  • Graphene liquid cells facilitate electron microscopy studies of nano crystal formation. (wikipedia.org)
  • Theory
  • In 1926 Hans Busch published work extending this theory and showed that the lens maker's equation could, with appropriate assumptions, be applied to electrons. (wikipedia.org)
  • 2016
  • Using advanced correlative microscopy to study complex biological samples in Encyclopedia of Analytical Chemistry", eds R.A. Meyers, John Wiley: Chichester, a9473 (2016) Voorneveld, Philip W., et al. (wikipedia.org)
  • structural
  • A significant improvement in structural features was achieved in 2012 by the introduction of direct electron detectors and better computational algorithms. (wikipedia.org)
  • sample
  • 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)
  • The surface of the block of resin-embedded sample is imaged by detection of back-scattered electrons. (wikipedia.org)
  • Some electrons penetrate the sample surface and escape into vacuum. (wikipedia.org)
  • A wide spectrum of electrons is emitted with energies between the energy of the illumination and the work function of the sample. (wikipedia.org)
  • Play media Cryo-electron microscopy (cryo-EM), or electron cryomicroscopy, is a form of transmission electron microscopy (TEM) where the sample is studied at cryogenic temperatures (generally liquid-nitrogen temperatures). (wikipedia.org)
  • A version of electron cryomicroscopy is cryo-electron tomography (CET), where a 3D reconstruction of a sample is created from tilted 2D images. (wikipedia.org)
  • In addition, the high vacuum required on the column of an electron microscope makes the environment for the sample quite harsh. (wikipedia.org)
  • Alternate modes of use allow for the TEM to observe modulations in chemical identity, crystal orientation, electronic structure and sample induced electron phase shift as well as the regular absorption based imaging. (wikipedia.org)
  • Traditionally, samples would be imaged using two separate microscopy modalities, potentially at different facilities and using different sample preparation methods. (wikipedia.org)
  • Early experiments mostly used TEMs, because the image is captured in a single frame, whereas the Scanning Electron Microscope must move or scan across the sample while the stimuli is being applied, altering the sample. (wikipedia.org)
  • The "fast" electrons travel through an objective lens and begin decelerating to low energies (1-100 eV) near the sample surface because the sample is held at a potential near that of the gun. (wikipedia.org)
  • The low-energy electrons are now termed "surface-sensitive" and the near-surface sampling depth can be varied by tuning the energy of the incident electrons (difference between the sample and gun potentials minus the work functions of the sample and system). (wikipedia.org)
  • The intensity distribution of the diffraction pattern will depend on the periodicity at the sample surface and is a direct result of the wave nature of the electrons. (wikipedia.org)
  • High-resolution transmission electron microscopy (HRTEM) (or HREM) is an imaging mode of the transmission electron microscope (TEM) that allows for direct imaging of the atomic structure of the sample. (wikipedia.org)
  • However, a large part of the structure information of the sample is contained in the phase of the electron wave. (wikipedia.org)
  • The interaction of the electron wave with the crystallographic structure of the sample is complex, but a qualitative idea of the interaction can readily be obtained. (wikipedia.org)
  • Each imaging electron interacts independently with the sample. (wikipedia.org)
  • Above the sample, the wave of an electron can be approximated as a plane wave incident on the sample surface. (wikipedia.org)
  • The exact description of dynamical scattering of electrons in a sample not satisfying the weak phase object approximation (WPOA), which is almost all real samples, still remains the holy grail of electron microscopy. (wikipedia.org)
  • As a result of the interaction with a crystalline sample, the electron exit wave right below the sample φe(x,u) as a function of the spatial coordinate x is a superposition of a plane wave and a multitude of diffracted beams with different in plane spatial frequencies u (spatial frequencies correspond to scattering angles, or distances of rays from the optical axis in a diffraction plane). (wikipedia.org)
  • magnetic
  • In 1858 Plücker observed the deflection of "cathode rays" (electrons) with the use of magnetic fields. (wikipedia.org)
  • The device used two magnetic lenses to achieve higher magnifications, arguably creating the first electron microscope. (wikipedia.org)
  • differential
  • At lower magnifications TEM image contrast is due to differential absorption of electrons by the material due to differences in composition or thickness of the material. (wikipedia.org)
  • Therefore, electron microscopy in conjunction with differential heavy atom DNA labeling could be used to directly image the DNA in order to determine its sequence. (wikipedia.org)
  • dense
  • The ultrathin sections are collected on 3mm copper (mesh) grids and stained with uranyl acetate and lead citrate to make the contents of the tissue electron dense (and thus visible in the electron microscope). (wikipedia.org)
  • energy
  • The energy imparted on the traveling slow electrons by the external electrode field is sufficient to ionize the gas molecules through successive (cascade) collisions. (wikipedia.org)
  • Schulten classified electrons into covalent and non-covalent states, and determined that electrons that acted in a coordinated (covalent) manner used less energy than those which were independent (non-covalent). (wikipedia.org)