bluuebunny/crossref_metadata_2025_split huggingface dataset:
Robust Fiber-Optic Coupled Confocal Raman Microscopy for Research and Quality Control Applications
Authors: Pelletier MJ , Slater J , Davis KL , Kowalchyk WK , Lewis IR 
Published: July 2020

Abstract
In this paper we report the continuing development of a novel fiber-optic coupled confocal Raman microscope which can offer spectral resolutions up to 0.6 cm−1 per pixel, spatial resolutions of 1 micron or less with axial resolutions of 2-3 microns. The system is based around a compact base unit which comprises a compact solid-state laser, a proprietary f/1.8 imaging spectrograph, and a TE-cooled CCD detector operating at −70°C.
In Figure 1 a schematic of the fiber coupled microscope is shown. The microscope includes a integrated holographic filter module to prevent silica Raman generated in the excitation fiber from reaching the sample and to reject radiation at the excitation wavelength from being returned to the spectrograph via the collection fiber(s). The architecture has been designed to allow both fluorescence imaging and Raman microspectroscopy to be accomplished without removing the sample. The figure also depicts the positions of linear polarizers which can be used to collect polarized Raman spectra from small particles or thin polymer laminate samples.
Different Mapping Algorithms for the Analysis of Exfoliated Cervical Cells by Infrared Microscopy
Authors: Lowry SR , Smith MJ , Leimer BA 
Published: July 2020

Abstract
The Papanicolaou (Pap) smear is the technique used to screen for abnormalities in cervical cells that may be related to cervical cancer and other problems. A number of research groups have reported results that indicate the infrared or NIR spectroscopy can be used to differentiate between samples of normal cervical cells and abnormal cells.
In this paper we will describe studies performed on cervical cell samples with an infrared microscope and a motorized x-y stage. This configuration allowed us to “Map” the sample in 100 micron increments, where an infrared spectrum is acquired at each point. This integrated system also allowed chemometric algorithms developed with the Nicolet TQ Analyst software to be automatically applied to the spectral data. Samples of cervical cells were obtained from patients using the standard procedure. Part of the sample was used to prepare the Pap smear slide and the remainder was placed in a saline solution and centrifuged for several minutes. The cell suspension was then applied to a Barium Fluoride 5mm X 5mm window and dried.
Near-infrared Imaging in Stroke Research
Authors: Dempsey RJ , Buice RG , Symons WC , Lodder RA 
Published: July 2020

Abstract
Accurate and nondestructive measurement of different lipoproteins simultaneously in carotid plaque in stroke patients using near-infrared (IR) imaging spectrometry seems possible for research. The lipoprotein composition of the plaque appears to have an impact on the outcome of the disease process. Carotid atherosclerosis without associated thrombosis is frequently a benign disease that is asymptomatic, although TIAs may be present in other cases. Many patients with carotid atherosclerosis can be treated surgically by endarterectomy with high initial success and favorable long-term prognosis. The acute manifestation of carotid atherosclerosis - stroke - arises when thrombus or ulceration develop. This potentially life-threatening complication probably develops at the site of plaque fissure or rupture. Recent research by others indicates that it is not the severity of stenosis (plaque volume) that determines the outcome: it is the type of stenosis (plaque chemical composition) and the extent of collateral growth.
Characterization of Keratin Pearls in Oral Squamous Cell Carcinoma Using FT-IR Microspectroscopy
Authors: Schultz CP , Liu K-Z , Kerr PD , Mantsch HH 
Published: July 2020

Abstract
Oral squamous cell carcinoma (SCC) positive biopsies from patients who underwent excision procedures by micrographical surgery were analyzed by FT-IR microspectroscopy in order to examine a specific fine structure of abnormal epithelial growth - the so-called keratin pearls. Taken from the oral cavity of 15 SCC positive patients, all biopsies indicated poorly or well-differentiated cancer containing smaller and larger pearls. In some cases only a few pearls were present; in others many of various sizes.
After surgery the biopsies were rapidly frozen in liquid nitrogen and stored at -80°C before thin sectioning the tissue for infrared measurements. The frozen tissue was then sliced into 8 μm thin sections and dried on an infrared-transparent Bal2window. For comparison one slice of tissue was always used for hematoxylin and eosin staining by drying it on a standard microscope slide. This procedure creates a series of thin sections on BaF2 and glass following an alternate pattern of one 8 μm section for IR microspectroscopy and the next 8 μm one for microscopy.
Infrared Microscopic Imaging of the Diffusion of Liquid Crystals into Thermoplastics
Authors: Wall Bentley G , Snively Chris M , Koenig Jack L 
Published: July 2020

Abstract
Thermoplastic polymer/liquid crystal systems have found application in the generation of display devices known as thermoplastic, polymer dispersed liquid crystals (PDLCs). These systems take advantage of the beneficial properties of both components to generate a device that has unique optical properties. The liquid crystal is dielectric and responds to an electric field. The polymer confines the liquid crystal so that the cells are closed. The two components are melted together until they are miscible. At lower temperatures, the two components phase separate. The liquid crystal component is the minor phase and takes the form of many tiny droplets contained within the major-phase, polymer matrix. An application of an electric field across these systems causes the liquid crystal within the droplets to align with the field. The systems are engineered such that when this alignment occurs there is no refractive index difference between the liquid crystal in the droplets and the polymer matrix, thus, the cells appear optically transparent. When there is no field applied, the liquid crystals in each droplet are aligned without respect to a general direction according to the surface energetics of each droplet/polymer interface. When this is the case, there is a refractive index mismatch between the droplets and the polymer and the cells are opaque. Research of these systems is aimed at improving the optical properties in order to facilitate the manufacturing of improved devices utilizing this technology. Because these systems are generated by a diffusion-controlled, phase separation process, understanding the relevant parameters, particularly the diffusion coefficients, should enable the manufacturing processes of these systems to be controlled more efficiently, generating improved optical properties.
Micro-Raman Spectroscopy for the Characterization of Materials in Electronic and Photonic Devices
Authors: D.Tuschel David 
Published: July 2020

Abstract
Materials characterization is the primary application of macro- and micro-Raman spectroscopy in our laboratory. Specifically, we wish to correlate chemical bonding and short to long range translational symmetry (including amorphous, highly oriented, polycrystalline, and single crystal materials) to physical, optical and electronic properties of materials and devices. Raman spectroscopy is particularly useful in this capacity because of its origin in the vibrational motions of chemically bonded atoms and its dependence upon crystal symmetry through the polarization selection rules. Furthermore, the high spatial resolution and non-destructive nature of micro-Raman spectroscopy make it ideal for in situcharacterization of electronic and photonic devices. We will present results of materials characterization studies, performed using macro- and micro-Raman spectroscopy, of electronic and photonic devices. In addition, we will discuss how the Raman polarization selection rules can be advantageously applied to device characterization.
A primary area of investigation involves the study of ion-implanted and annealed Si by Raman spectroscopy.
“Mute Witnesses, Sure and Faithful”: Microscopic Analysis of Textile Fibers in Criminal Cases
Authors: Houck MM 
Published: July 2020

Abstract
Placing the suspect at the crime scene is an important element in the solution of a crime. A way to do this is to find textile fibers like those from the victim’s environment or the crime scene on the clothing of the suspect. Another way would be to discover fibers like the suspect’s clothing or environment on the victim or at the crime scene. When fibers exhibiting the same microscopic characteristics and optical properties are found in common between a known source and the suspect or victim, an evidentiary value is placed on that association. This value is dependent on many factors that include the type(s) of fibers found (natural or synthetic), the color (s) of the fibers, number of fibers found, the location of fibers on a victim, suspect and/or crime scene and the number of different fibers that “match,” especially if different fibers from the same item of clothing or fibers from more than one item of clothing are found.
Visualizing Molecular Species Within Inorganics: Raman Chemical Imaging of Minerals, Meteorites and Actinides
Authors: Kline Nicole J , Sparrow Mark C , Treado Patrick J 
Published: July 2020

Abstract
Raman chemical imaging microscopy is a powerful technique for the characterization of a wide host of materials, including inorganic species. The technique makes use of a liquid crystal tunable filter (LCTF) imaging spectrometer that is integrated within an infinity-corrected optical microscope. The imaging system provides the performance of a dispersive Raman spectrometer at every pixel of the charge-coupled device (CCD) detector used to capture the Raman image.
We are currently applying Raman microscopy to the chemical imaging analysis of mineral composition and phase chemistry found in meteorites and terrestrial minerals. Determination of the chemical composition and structure of mineral components is often useful in developing an understanding of the petrologic process that formed the minerals, including those minerals that have been exposed to water. This is of particular interest in light of recent promising evidence of past life in Martian meteorites.
FT-IR Spectroscopic Imaging in the Infrared “Fingerprint”Region Using an Mct Array Detector
Authors: Crocombe R A , Wright N , Drapcho DL , McCarthy WJ , Bhandare P , Jiang EJ 
Published: July 2020

Abstract
A new infrared spectroscopic imaging technique has been described, combining step-scan Fourier transform (FT) Michelson interferometry with indium antimonide (InSb) focal-plane array (FPA) image detection [1-3], for use in the range 3950-1975 cm−1. The coupling of such detector to an interferometer provides an optimized method for infrared spectroscopic imaging by simultaneously realizing both a multiplex and multichannel advantage. Specifically, the multiple detector elements enable spectra at all pixels to be collected simultaneously, while the interferometer allows all the spectral frequencies to be measured concurrently. This technique can rapidly generate very high quality, chemically specific images from a wide variety of samples. Preliminary results from the use of a mid-infrared liquid-helium-cooled arsenic-doped-silicon array have also been reported recently [4]. Focal-plane arrays using mercury-cadmium-telluride (MCT) are now commercially available, giving access to the range 3950-800 cm−1, and greatly broadening the applicability of this technique [5].
FT-IR microscopy does not require exotic sample preparation -- samples can be examined in transmission and reflectance, do not need to be stained or coated, and a vacuum is not required.
Multivariate Visualiztion and Analysis Tools for Segmentation and Classification of Vibrational Spectroscopic Images
Authors: Delaglio F , Kidder LH , Levin IW , Lewis EN 
Published: July 2020

Abstract
Vibrational spectroscopic imaging has already demonstrated enormous potential for studying a variety of chemical and biological systems at both the microscopic and macroscopic level. However, these spectral images are large and complicated, typically consisting of tens of thousands of pixels, each with an associated high-resolution vibrational spectrum, leading to data sizes upwards of 64 megabytes. In order to realize the full potential of these spectral images, we must find ways to query the data so that specific questions can be answered.
We illustrate a multivariate approach to this challenge, where each pixel is considered to be a single point in a multivariate (N-dimensional) space. The variables (coordinates) of the point in N dimensions are simply the intensities of the N-point spectrum associated with the pixel. In this representation, pixels with similar spectra will tend to cluster together in the multivariate space, since they will have similar coordinates.
Limitations of Sem Characterization of Semiconductors
Authors: Joy David C 
Published: July 2020

Abstract
The field of semiconductor materials and devices represents a unique challenge to microscopy and microanalysis because the standard of excellence is constantly changing. Driven by the imperative of Moore's law (illustrated in figure 1) - which predicts that the density of devices in a chip doubles every three years - the spatial resolution that must be achieved increases by a factor of two every five years. The problem of meeting this demand is further enhanced by the widespread sentiment that all e-beam tools used on semiconductors should operate at low beam energies (typically below lkeV). Finally, the increase in device packing density and the expected move to 30cm. diameter wafers as substrates for fabrication also means that the microscopist will be faced with the challenge of rapidly and reliably finding a given device or feature among the 108 or so similar features which are present.
The first need is to be able to monitor the basic steps of the fabrication process. Given the assumption that by the year 2001 devices will be built on 0.18μm design rules, it will then be necessary to perform critical dimension metrology with a precision of 2 to 3nm (see figure 2).
Electron Backscatter Diffraction In The Sem: Is Electron Diffraction In The Tem Obsolete?
Authors: Michael J R , Schlienger M E , Goehner R P 
Published: July 2020

Abstract
The technique of electron backscatter diffraction (EBSD) in the scanning electron microscope is currently finding a large number of important applications in materials science. The patterns formed through EBSD were first studied over 40 years ago. It has only been in the last 10 years that the technique has really begun to have an impact on the study of materials. The introduction of automatic pattern indexing software has enabled the technique to be used for mapping the orientation of a polycrystalline sample. The more exciting and universally interesting application of the technique has been the identification of micron and sub-micron sized crystalline phases based on their chemistry and crystallography determined by EBSD.
EBSD is obtained by illuminating a highly tilted sample (&gt;45° from horizontal) with a stationary electron beam. Electrons backscattered from the sample may satisfy the condition for channeling and will produce images that contain bands of increased and decreased intensity that are equivalent to electron channeling patterns.
Low Beam Energy X-Ray Micro Analysis: How Useful Is It?
Authors: Newbury Dale E 
Published: July 2020

Abstract
Throughout the history of electron-beam X-ray microanalysis, analysts have made good use of the strong dependence of electron range on incident energy (R ≈ E1,7) to optimize the analytical volume when attacking certain types of problems, such as inclusions in a matrix or layered specimens. The “conventional” energy range for quantitative electron beam X-ray microanalysis can be thought of as beginning at 10 keV and extending to the upper limit of the accelerating potential, typically 30 - 50 keV depending on the instrument. The lower limit of 10 keV is selected because this is the lowest incident beam energy for which there is a satisfactory analytical X-ray peak excited from the K-, L-, or M- shells (in a few cases, two shells are simultaneously excited, e.g., Fe-K and Fe-L) for every element in the Periodic Table that is accessible to X-ray spectrometry, beginning with Be (Ek =116 eV) and extending to the transuranic elements. This criterion is based upon establishing a minimum overvoltage U = E0/Ec &gt; 1.25, which is the practical minimum for useful excitation.
X-Ray Emission of Porous Materials In The Scanning Electron Microscope Computed Using Monte Carlo Simulations
Authors: Gauvin Raynald 
Published: July 2020

Abstract
Conventional quantitative X-ray microanalysis in the scanning electron microscope or in the electron microprobe is valid for specimens of bulk homogeneous composition and with flat and polished surfaces. Quantitative methods, using X-ray microanalysis and Monte Carlo simulations of electron trajectories in solids, have been developed for the chemical analysis of spherical inclusions embedded in a matrix and for multilayered specimens. In this paper, the effect of porosity and of the size of the pores are investigated concerning their effect on X-ray emission using Monte Carlo simulation of electron trajectories in solids since porous materials are of great technological importance.
This new Monte Carlo program uses elastic Mott cross-sections to compute electron trajectories and the Joy & Luo modification of the continuous Bethe law of energy loss and the details are given elsewhere. This program assumes that all the pores are spherical and have the same size.
Parametrization of The Range of Electron At Low Energy (Eo &lt; 10 Kev) Using The Casino Monte Carlo Program
Authors: Hovington Pierre , Drouin Dominique , Gauvin Raynald , Joy David C 
Published: July 2020

Abstract
The range of electrons for a given beam energy and atomic number is one of the most valuable piece of information a microscopist must know before carrying out qualitative and quantitative analysis of heterogeneous samples in a scanning electron microscope (SEM). The frequently used parametrization of Kanaya & Okayama is only « valid » at high energy (EO &gt; 10 keV). However, with the advent of Field Emission Gun SEM (FEGSEM) most of the effort has been toward low energy analysis where no parametrization is available yet. In this paper, the parametrization of the range of electrons at low energy as a function of atomic number and beam energy will be presented for both the backscattered and the internal electrons.
The distribution of the maximum depth reached by 250 k electrons generated by the CASINO Monte Carlo program2 was used to compute the range for 10 elements at 20 energies.
High Precision Multiple Kev X-Ray Analysis: Tests of Ionization Cross Sections and Monte Carlo Algorithms
Authors: Armstrong John T , Newbury D E , Carpenter P K 
Published: July 2020

Abstract
Determination of the variation of absolute and relative electron-excited x-ray production rates as a function of electron beam energy and sample atomic number is necessary for calculation of the "stopping power" atomic number correction and the relative amount of characteristic fluorescence and for development of “standardless” and Monte Carlo algorithms for quantitative x-ray analysis. Critical to the calculation of x-ray production rates is an accurate expression for the inner shell electron ionization cross section. A large number of expressions have been proposed for the relative x-ray production rates (used in the fluorescence correction)1 and for the ionization cross section used in the atomic number correction, and these yield quite different results. In order to evaluate which expressions gave the most accurate results when applied to quantitative x-ray emission measurements, we performed a series of high precision measurements of x-ray intensities as a function of electron beam accelerating potential for a series of pure element and simple oxide, phosphide, sulfide, and chloride standards for 65 elements ranging in Z from C to U
The Use of Collimating X-Ray Optics For Wavelength Dispersive Spectroscopy
Authors: Agnello R , Howard J , McCarthy J , OHara D 
Published: July 2020

Abstract
There has been much interest in the last few years in the technique for focusing x-rays into high intensity spots using tapered glass capillaries or other forms of grazing incident x-ray reflectors. The resulting microbeams have been used in applications that include microfluorescence, microdiffraction, tomography and lithography. Instead of focusing x-rays to a spot, a collimating optic can be used to capture x-rays from a point source and turn them into a collimated parallel beam at the exit aperture to the optic. Kirkland et. al. have pointed out that the use of such an optic could provide enhanced detection sensitivity in wavelength dispersive spectroscopy.
We have developed a grazing incidence collimating x-ray optic that can be coupled to a simple wavelength dispersive spectrometer (WDS). This combined instrument was designed to enhance the intensity of x-rays from a sample by an order of magnitude or more in the energy range of 0 to 1 keV compared to a conventional WDS.
Standardless Quantification of Conductive Oxides In The Sem
Authors: Dijkstra JM , Shen RB 
Published: July 2020

Abstract
In the last 10 years the development of new polymer type detector window materials has dramatically increased the opportunities for light element analysis with Energy Dispersive Spectrometers (EDS). With the introduction of light-element analysis the need also arises to accurately quantify X-ray spectra. Traditional quantification techniques, using a probe current measuring device and pure elemental standards, have been introduced into the field of EDS, but these techniques prevented much of the conveniences of the EDS techniques with respect to speed and ease of use. Many users are therefore willing to sacrifice part of the maximum achievable accuracy in return for a method that is more convenient: standardless analysis.
With EDS analysis the widely published ZAF and φ(ρz) models can be used to convert relative intensities into weight percentages, but for standardless analysis the inaccuracy of the result is mainly caused by the reference intensities.
Trace Element Detection In Particle X-Ray Spectrum
Authors: Small John A 
Published: July 2020

Abstract
One of the main goals of automated scanning electron microscopy analysis (ASEM) of particles is to provide macroscopic phase and compositional information on particle populations based on the energy dispersive x-ray spectrometry, EDS, analysis of several hundred to several thousand individual particles from the sample. The selection and identification of the various elemental groupings is often accomplished by applying techniques for grouping data, such as multivariate or cluster analysis methods, to characteristic x-ray intensities or normalized elemental concentrations. Particle groupings are often based on major and minor elements with concentrations greater than about 1-2 wt. percent. At these concentration levels, the peak-to-background ratios for the characteristic x-ray peaks are sufficiently large that in the absence of severe peak overlaps the elements can be easily identified even in spectra with poor counting statistics. Additional refinement in particle groupings may be possible if reliable information can be obtained on the trace elements present in particles at less than about 1-2 wt.%.