bluuebunny/crossref_metadata_2025_split huggingface dataset:
Minimum-size detection limit for volcanic glass particles using automated scanning electron microscopy
Authors: Germani Mark S. 
Published: June 2020

Ice cores contain a detailed record of fallout from large volcanic eruptions. Identification of volcanic glass particles is used to aid in dating ice cores (tephrachronology). In addition, it should be possible to relate concentrations of volcanogenically-derived species; silicate glass particles, sulfate (from oxidation of SO2), chloride and fluoride to atmospheric levels which existed shortly after eruption. This information, coupled with proxy meteorological records from the core, can be used to assess the climatic impact from major volcanic eruptions.Automated scanning electron microscopy has been used to detect volcanic glass particles >1 μm in diameter in ice core meltwater samples filtered onto Nuclepore filters. It is important to be able to detect submicrometer volcanic glass particles because of their longer atmospheric residence time and the fact that they comprise a significant portion of the number of glass particles deposited in an ice core. Existing procedures for automated analysis of micrometer size particles need to be modified to efficiently analyze submicrometer particles.
Automated digital electron microscope used to establish cleanliness levels of disk drive components
Authors: Monson Gene 
Published: June 2020

Establishing a cleanliness level is a critical function that must be satisfied for quality manufacturing. It is used for bench marking and setting vendor qualifying specifications. The liquid particle counter (LPC) is used to quantify the particle count of a part that has been extracted with water and ultrasonic energy. Then the liquid is filtered into a small pore filter (0.4um). The filter can be analyzed with scanning electron microscopy (SEM). Additionally particles that are found can be analyzed with energy dispersive x ray spectroscopy (EDS). With the use of an automated digital SEM with image analyzer it is possible to analyze a statistically significant portion of the particles to have confidence in the resulting data.With a totally automated SEM parameters of operation such as beam accelerating voltage, current, emission, spot, filament temperature, gun bias, are stored to memory. Magnification, scan speed, stigmator, detector, and condenser settings, and stage geometry are also stored.
The characterization of lead smelter dusts by automated scanning electron microscopy
Authors: Vander Wood Tim B. 
Published: June 2020

The dust derived from smelting and other mining/metallurgical processes is increasingly viewed as a resource rather than a hazardous waste. In order to determine the most appropriate technologies for resource recovery from these dusts and other hazardous wastes, they must be examined in some detail for particle size, chemistry, phase composition, etc. Automated scanning electron microscopy combined with energy-dispersive x-ray spectrometry (ASEM-EDS) provides a tool for rapidly determining the particle size distribution and chemistry on a representative dust sample so that the most appropriate processing methods can be chosen.ASEM-EDS analyses were performed on five dust samples that had previously been examined by traditional techniques of ore microscopy. Each sample was from a distinct area of the Herculaneum Lead Smelter: 1) Blast Furnace Area, #2) Dross Furnace Area, #3) Refinery Area, 4) Sinter Plant near the scrubber and #5) Sinter Plant near the crusher. Approximately 200 mg of each dust were dispersed in 100 ml of 20 ppm methyl cellulose/water solution, and a droplet of each dispersion was placed on a polished carbon planchet.
Confocal Raman mapping
Authors: Barbillat J. , Delhaye M. , Dhamelincourt P. 
Published: June 2020

Raman mapping, with a spatial resolution close to the diffraction limit, can help to reveal the distribution of chemical species at the surface of an heterogeneous sample.As early as 1975,three methods of sample laser illumination and detector configuration have been proposed to perform Raman mapping at the microscopic level (Fig. 1),:- Point illumination:The basic design of the instrument is a classical Raman microprobe equipped with a PM tube or either a linear photodiode array or a two-dimensional CCD detector. A laser beam is focused on a very small area ,close to the diffraction limit.In order to explore the whole surface of the sample,the specimen is moved sequentially beneath the microscope by means of a motorized XY stage. For each point analyzed, a complete spectrum is obtained from which spectral information of interest is extracted for Raman image reconstruction.- Line illuminationA narrow laser line is focused onto the sample either by a cylindrical lens or by a scanning device and is optically conjugated with the entrance slit of the stigmatic spectrograph.
New frontiers in infrared microspectroscopy
Authors: Harthcock M. A. , McKelvy M. L. , Pell R. J. 
Published: June 2020

Infrared microspectroscopy has become a common technique for the microanalysis of material. Characterization of spatially specific areas using infrared spectroscopy has been applied to a wide range of materials/systems including, for example, multi-layer films, silicon wafer contamination and inclusions in a variety of systems, surface contamination, orientation in single fibers. In addition, infrared microspectroscopy mapping experiments have been used to obtain images of materials based on functional group absorptions that characterize system composition.The spatial resolution of the technique is limited to approximately 10-20 micrometers experimentally, due to diffraction limitations. Infrared ultra-microspectroscopy has been mentioned by Messerschmidt as a technique to achieve resolution below the diffraction limit of the radiation (e.g. 5 micrometers). However, in the absence of experimental technology to routinely increase the spatial resolution from which unique infrared spectra can be obtained, we have applied factor analysis techniques to effectively increase the spatial resolution from which an infrared spectrum could be obtained.
Near-IR imaging microscopy using an acousto-optic tunable filter (AOTF)
Authors: Treado Patrick J. , Levin Ira W. , Neil Lewis E. 
Published: June 2020

Near-infrared spectroscopy is a sensitive and non-invasive probe for chemical analyses. The integration of spectroscopic and imaging technologies is a potent tool for the study of a wide range of biological materials.Continuously tunable acousto-optic filters operable in the ultraviolet, visible and infrared are now widely available. These computer controlled notch filters provide random wavelength access, wide spectral coverage and moderate spectral resolution. AOTFs potentially have a wide range of spectroscopic applications. We employ AOTF technology for visible/NIR absorption microscopy between 600-2000 nm.The microscope is constructed around an acousto-optic device coupled to an infinity corrected microscope employing either silicon or indium antinomide focal-plane array detectors. In operation, the AOTF is used to spectrally filter a quartz halogen light source. Under computer control the AOTF is swept through a wavelength range and at predetermined intervals images are recorded. Hundreds of frames may be collected, and the spectral image data set can readily comprise many megabytes of data.
High-performance time - of - flight SIMS
Authors: Benninghoven A. 
Published: June 2020

Progress in many fields of science and technology strongly depends on the availability of appropriate analytical techniques. This becomes increasingly true for all surface related technologies. A most important analytical information concerns the chemical composition of the uppermost monolayers. This information should be supplied with high sensitivity and high resolution, not only for the elemental but also for the molecular surface composition.Time - of - Flight SIMS supplies this molecular information, which cannot be obtained by other surface analytical techniques as AES (Auger electron spectroscopy), XPS (photoelectron spectroscopy), electron microscopy or the electron microprobe. The extremely high transmission allows static SIMS surface analysis with high lateral and mass resolution. Depending on the primary ion source, lateral resolutions below 100 nm are achieved. The Time - of - Flight technique allows parallel acquisition of a large number of ion images. It features an unlimited mass range obtained with an ultimate sensitivity based upon the parallel mass registration and the high transmission.
Microanalysis of individual silver halide microcrystals
Authors: Wu S. , Van Daele A. , Jacob W. , Gijbels R. , Verbeeck A. , De Keyzer R. 
Published: June 2020

There is a considerable interest for the study of the elemental distribution and composition in silver halide photographic emulsions, particularly for the microanalysis of individual microcrystals. In this work, elemental distributions and contents of tabular and cubic silver halide microcrystals were obtained by backscattered electron imaging (BSEI), scanning transmission electron imaging (STEI), x-ray mapping and x-ray microanalysis in a scanning electron microscope (STEM) combined with energy-dispersive x-ray analysis (EDX).Several kinds of silver halide microcrystals were prepared, After removing the gelatin, repeated centrifugation and washing in distilled water, the grains were resuspended and dispersed onto carbon coated 50 mesh copper grids. All analyses were carried out on a JEOL 1200 EX electron microscope equipped with detectors for backscattered, secondary and transmitted electrons and an energy dispersive x-ray analysis system. An image processing system was used for acquiring and processing BSE images, STE images and x-ray maps. The role of the image processing computer system (IBAS Kontron) is twofold: it allows to optimize the acquisition conditions and to process the images afterwards.
Ziebold-ogilvie after 25 years: A new superior α-factor correction for the quantitative analysis of metal alloys and compounds
Authors: Armstrong John T. 
Published: June 2020

One of the first empirical correction procedures for quantitative electron microprobe analysis was the Ziebold-Ogilvie or so-called α-factor correction. This procedure assumed that in binary element systems (AB) there is a hyperbolic relation between relative emitted x-ray intensity (KA,AB) and relative concentration (CA,AB) such that:orwhere αA,AB is a constant for the binary AB. However, evidence developed that, for binary metal alloys when matrix corrections (particularly characteristic fluorescence) were high, the assumption that a is composition-independent was incorrect and the procedure produced significant systematic errors. Therefore, the α-factor procedure has never been widely-used for the analysis of metal alloys or similar samples. This paper proposes that if the constant α-factor in the Ziebold-Ogilvie procedure were replaced by a simple, composition-dependent polynomial expression, the resulting procedure were replaced by a simple, composition-dependent polynomial expression, the resulting correction procedure would be of equal accuracy to any of the currently-used correction methods.Armstrong proposed that the α-factor procedure could be made more accurate if the constant αA,AB is replace by a polynomial (composition dependent) expression:
Raman analysis of microcircuits with lead zirconate titanate (PZT) films
Authors: Tallant D. R. , Schwartz R. W. , Tuttle B. A. , Everist S. C. , Tafoya B. C. 
Published: June 2020

Certain compositions and structural forms of lead zirconate titanate (PZT) materials have potential applications in microelectronics because of their ferroelectric properties. One such application is in the development of new types of non-volatile memories. PZT films are integrated into microcircuit components using sol-gel deposition techniques. The solution chemistry effects attendant to different sol-gel preparation procedures have been investigated by several researchers.We have used Raman spectroscopy both to characterize the metallo-organic species initially laid down on macroscopic platinum substrates during sol-gel processing and to follow the evolution of Pb-Zr-Ti oxide species through high temperature processing. The high temperature processing removes residual organics and creates Pb-Zr-Ti oxide structures that have ferroelectric properties. Low temperature pyrochlore structures, which are not ferroelectric, can be distinguished by Raman spectroscopy from tetragonal and pseudo-cubic/rhombohedral perovskite structures, which are usefully ferroelectric (Top Figure). In addition Raman spectroscopy has identified lead and titanium oxides that form as intermediates in the high temperature crystallization of ferroelectric PZT structures.
Microchemistry of ZnO Varistors
Authors: Soni K. K. , Hwang J. , Dravid V. P. , Mason T. O. , Levi-Setti R. 
Published: June 2020

ZnO varistors are made by mixing semiconducting ZnO powder with powders of other metal oxides e.g. Bi2O3, Sb2O3, CoO, MnO2, NiO, Cr2O3, SiO2 etc., followed by conventional pressing and sintering. The non-linear I-V characteristics of ZnO varistors result from the unique properties that the grain boundaries acquire as a result of dopant distribution. Each dopant plays important and sometimes multiple roles in improving the properties. However, the chemical nature of interfaces in this material is formidable mainly because often trace amounts of dopants are involved. A knowledge of the interface microchemistry is an essential component in the ‘grain boundary engineering’ of materials. The most important ingredient in this varistor is Bi2O3 which envelopes the ZnO grains and imparts high resistance to the grain boundaries. The solubility of Bi in ZnO is very small but has not been experimentally determined as a function of temperature.In this study, the dopant distribution in a commercial ZnO varistor was characterized by a scanning ion microprobe (SIM) developed at The University of Chicago (UC) which offers adequate sensitivity and spatial resolution.
Analysis of philadelphia aerosol
Authors: Wight Scott 
Published: June 2020

Size distributions and compositions of atmospheric aerosol are important since they affect such processes as pollutant deposition, visibility reduction, human health, smog formation, and chemical reactions in the atmosphere. Natural and anthropogenic high-temperature combustion sources discharge an abundance of fine particulate material, often with the majority of the mass in the sub-micrometer sized particles. The sub-micrometer particle range is of special interest for source identification because the larger particles are efficiently trapped by the particulate control devices, and the sub-micrometer aerosol exhibits longer residence times in the atmosphere. Insight into the contributing sources to an aerosol population can be gained by investigating the morphology and elemental composition of particles as a function of size.The Philadelphia area is a highly industrialized urban airshed with many discrete sources of aerosol. Philadelphia atmospheric particulate material has been previously characterized with a dichotomous sampler, which produced only two size fractions with a size cutoff at 2.5 μm.
Development of a standard reference material for analysis of asbestos on filters by TEM
Authors: Turner S. , Steel E.B. , Phelps J.M. , Windsor E.S. , Doorn S.S. , Leigh S.D. 
Published: June 2020

Over one-hundred and fifty TEM laboratories in the U.S. are presently involved in the analysis of air, water or other fluids to determine the presence and concentration of asbestos. The analysis by transmission electron microscopy is not automated and requires an analyst to detect and identify particles. Evaluation of the analyst’s performance and assessment of the accuracy of the analyses are important objectives in quality assurance. One method of calibration is to analyze materials that have a known concentration of asbestos particles. The National Institute of Standards and Technology has provided Standard Reference Materials (SRMs) for such analyses. Previous SRMs for TEM analysis of asbestos on filters were comprised of chrysotile deposited from a liquid-based suspension. The development of a new SRM in which asbestos particles were deposited from air is described in the current work.Chrysotile asbestos fibers were deposited simultaneously onto an array of 320 mixed-cellulose-ester filters by use of an aerosol generator at the Stanford Research Institute.
The kumakhov lens: Prospects for x-ray microanalysis
Authors: Gibson Walter M. , Kumakhov Muridan A. 
Published: June 2020

A new optical system based on multiple reflection of X-rays and neutrons along specially shaped solid surfaces first proposed by Kumakhov has undergone intense and rapid development in the USSR and more recently in a joint development effort between the Institute for Roentgen Optical Systems (IROS) in Moscow, Russia, and the Center for X-Ray Optics (CXO) in Albany, NY. The most used X-ray Optical System (XOS) utilizes thin hollow microcapillary tubes arranged appropriately to capture X-rays from a divergent source to produce a quasiparallel beam or a focussed beam as shown schematically in Figure 1. Alternatively, a parallel beam of X-rays (or neutrons) can be deflected or focused. It is also possible to use such systems for energy filtering or energy selection.The first such systems were constructed from single hollow capillaries and showed that X-rays could indeed be captured and focussed as shown in Figure 2. These "first generation" Kumakhov optics are most efficient for relatively low energy X-rays (0.5-2 keV).
DXS: Differential absorption x-ray spectroscopy
Authors: Fisher Robert M. 
Published: June 2020

X-ray spectrochemical analysis, with either energy-dispersive (EDS) or wavelength-dispersive (WDS) systems, is is used extensively by electron microscopists to determine the chemical composition of selected features in a wide variety of specimens. Several decades of development have yielded efficient and rugged detector crystals and goniometer hardware as well as sophisticated, but user-friendly, software for quantitative chemical and image analysis. Nevertheless an alternative system, based on differential x-ray absorption with "balanced" transmission filters (DXS™) has attractive advantages as a simple, low cost, system for qualitative x-ray microanalysis which does not require liquid nitrogen. Computer processing of intensities obviates the former need for impossibly-precise adjustment of filter thickness. However the filter array must be preset for analysis of the elements that are believed to be present for routine work.DXS analysis is based on the abrupt change in x-ray absorption that occurs between particular elements. This is illustrated by the different mass absorption coefficients for Fe and Cr K radiation for a series of filters in increasing atomic number from Ti to Co as shown in Figure 1 (1,2).
Comprehensive multilayer film analysis with XPS, AES, and EDS
Authors: Miller N. C. 
Published: June 2020

Wavelength and energy dispersive x-ray spectroscopy (WDS and EDS) are routinely utilized to measure qualitatively and quantitatively the composition of microscopic features/phases of thickness 0.5 (μm or greater in solids. Surface spectroscopies, especially x-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES), are employed to determine surface chemistry and surface composition respectively of microscopic features 0.2-5 nm thick. The combined utilization of AES and EDS (or WDS) permits microanalysis of surface and subsurface features/phases. Two areas of improved analysis through combined utilization of AES and EDS are imaging/elemental mapping and measurement of vertical diffusion profiles. Strengths of XPS in complementing EDS/WDS will also be discussed.High resolution surface elemental or chemical mapping can be carried out with scanning Auger or secondary ion mass spectrometry (SIMS) microanalysis, respectively. In fact, both offer improved spacial resolution over WDS and EDS elemental x-ray dot mapping. Using sample rotation while removing material by ion beam sputter etching, three dimensional mapping can be carried out by either surface analysis technique, permitting microanalysis of buried features even in complex heterostructures.
Measurement of the Inelastic Mean Free Path by EELS Analyses of Submicron Spheres
Authors: Bonney Laura A. 
Published: June 2020

Accurate measurement of sample thickness is important for analytical electron microscopy (AEM) but is often difficult and tedious. Unlike other thickness measurement methods, with electron energy loss spectroscopy (EELS) thickness may be measured in both amorphous and crystalline specimens and at the same location and orientation at which other data is collected in the electron microscope. Thickness values may be obtained from convergent-beam electron diffraction (CBED) data only if the sample is crystalline with large grains of uniform thickness. Sample thickness may be measured from crystal defects projected through the entire foil, but such defects are not always conveniently located in the area of interest. The distance between contamination spots on the upper and lower surfaces of the specimen may be measured, but this is not considered accurate and contamination is not desirable in microanalysis.Sample thickness t may be determined with EELS by the relation:(1)where It is the total intensity in the EEL spectrum, Iz is the intensity in the zero loss peak, and λ is the inelastic mean free path for energy loss of an incident electron in the sample.
Parallel Detection of Electron Energy Loss Spectra in Direct Mode
Authors: Quandt Eckhard , laBarré Stephan , Hartmann Andreas , Niedrig Heinz 
Published: June 2020

Due to the development of semiconductor detectors with high spatial resolution -- e.g. charge coupled devices (CCDs) or photodiode arrays (PDAs) -- the parallel detection of electron energy loss spectra (EELS) has become an important alternative to serial registration. Using parallel detection for recording of energy spectroscopic large angle convergent beam patterns (LACBPs) special selected scattering vectors and small detection apertures lead to very low intensities. Therefore the very sensitive direct irradiation of a cooled linear PDA instead of the common combination of scintillator, fibre optic, and semiconductor has been investigated. In order to obtain a sufficient energy resolution the spectra are optionally magnified by a quadrupole-lens system.The detector used is a Hamamatsu S2304-512Q linear PDA with 512 diodes and removed quartz-glas window. The sensor size is 13 μm ∗ 2.5 mm with an element spacing of 25 μm. Along with the dispersion of 3.5 μm/eV at 40 keV the maximum energy resolution is limited to about 7 eV, so that a magnification system should be attached for experiments requiring a better resolution.