bluuebunny/crossref_metadata_2025_split huggingface dataset:
Industrial Applications of Near-Infrared Chemical Imaging Microscopy
Authors: Lewis EN , Kidder LH , Haber KS 
Published: July 2020

Abstract
Single point near-infrared (NIR) spectroscopy is used extensively for characterizing raw materials and finished products in a wide variety of industries: polymers, paper, film, pharmaceuticals, paintings and coatings, food and beverages, agricultural products. As advanced industrial materials become more complex, their functionality is often determined by the spatial distribution of their discrete sample constituents. However, conventional single point NIR spectroscopy cannot adequately probe the interrelationship between the spatial distribution of sample components with the physical properties of the sample. to fully characterize these samples, it is necessary to probe simultaneously spatial and chemical heterogeneity and correlate these properties with sample characteristics.
Recently, we have developed a novel NIR imaging spectrometer that can deliver spatially resolved chemical information very rapidly. in contrast to conventional, single point NIR spectrometers, the imaging system uses an infrared focal-plane array (FPA) to collect up to 76,800 complete spectra, one for each pixel on the array, in approximately one minute.
How Quantitative are Measurements in the Stem?
Authors: Silcox John 
Published: July 2020

Abstract
The typical electron micrograph is often rich in detail, sometimes too rich, and it can overwhelm the casual observer. The obvious interpretation may be quickly drawn and the next sample brought under study. Yet the electron interaction with the sample is rarely fully exploited. This may be the reason that electron microscopy may sometimes be dismissed as “just pretty pictures”. While in practice “pretty pictures” are not that easy to record or find, it is still true that the interaction of electrons with the sample is complex and therefore able to give the observer much more understanding than is normally found, provided only that the observer is able to unravel the observations. It is the rapid change in this situation that has been fascinating to watch unfurl during the past decades.
In the Scanning Transmission Electron Microscope (STEM) electrons are focused into a tiny spot that is scanned over a thin film specimen.
Electronic Properties of Carbon Nanotubes via Aloof Experiments Using Transmission-EELS
Authors: Reed Bryan W , Sarikaya Mehme 
Published: July 2020

Abstract
Carbon nanotubes (CNT) have great potential as one-dimensional quantum conductors in future molecular electronic applications. Local electronic property determinations at low energies in CNT have been confined to those made by scanning probe microscopy techniques (SPM). Although SPM measurements provide unprecedented electronic property information, they suffer from substrate coupling and a limited ability to measure structural characteristics of nanotubes. A high-resolution transmission electron microscope (TEM) coupled with an electron energy loss spectrometer (EELS) offers electronic property determination as well as structural (imaging and diffraction) and spectroscopic analysis of truly isolated nanotubes. Here we report measurements of EEL spectra of single-walled CNT, both singly and in bundles. The experiments were performed in a VG HB501 STEM at Cornell University, operating at 100 kV. CNT samples chosen for analysis include isolated single-walled tubes with diameters 1.2-1.3 nm and bundles of ∼3-150 single-walled tubes. Many of the spectra were obtained in the aloof mode, i. e. with the beam not penetrating the material.
HREM and LORENTZ Microscopy Studies on Sm(Co,Cu,Fe,Zr)z High Temperature Permanent Magnets
Authors: Zhang Y , Tang W , Hadjipanayis GC , Chen C , Liu JF , Nelson C , Krishnan K , Luo ZP , Miller DJ 
Published: July 2020

Abstract
Sm(Co,Cu,Fe,Zr)z 2:17 based permanent magnets have the highest Curie temperature and the most excellent temperature stability among the current rare-earth permanent magnets. in recent years, the Sm(Co,Cu,Fe,Zr)z magnets have attracted again considerable attention due to the demand of the Department of Defense for high temperature applications such as aircraft, spacecraft and ship systems. Our recent studies have led to the development of new precipitation hardened Sm(Co,Fe,Cu,Zr)z magnets with operating temperatures above 400°C and with coercivities as high as 10 kOe at 500°C. The microstructure of the Sm(Co,Cu,Fe,Zr)z high temperature magnets consists of a cellular structure (2:17 rhomobohedral cells surrounded by 1:5 hexagonal cell walls) superimposed on a lamella phase (2:17 hexagonal). This microstructure is sensitive to processing and to the alloy chemical composition. Magnetic domain structure studies play a critical role in understanding the magnetic hardening behavior of the magnets. in this paper, HREM and magnetic domain structure were studied in these Sm(Co,Cu,Fe,Zr) high temperature permanent magnets.
Future Direction of High-Resolution X-Ray Microanalysis in the AEM
Authors: Watanabe M , Williams DB 
Published: July 2020

Abstract
Current commercial analytical electron microscopes (AEMs) including scanning transmission electron microscopes (STEMs) are a compromise design between the highest spatial, analytical and energy resolutions. in contrast, a VG HB603 STEM at Lehigh University has been designed with a 300 kV cold field-emission gun and twin X-ray detectors to maximize X-ray generation and collection efficiencies [1]. in addition, instrumental features of almost no stray radiation, ultra-high vacuum (&lt;10−7 Pa in the stage and &lt;10−7 Pa in the gun), beam blanking and direct probe-current measurement in the HB 603 have transformed the approaches to quantitative analysis. By using such modern AEMs, it is now possible to perform X-ray microanalysis with the spatial resolution as low as 1.5 nm and the detectability limits of∽2 atoms in the analyzed volume [2]. Furthermore, even quantitative X-ray mapping becomes achievable, while maintaining, high spatial resolution (the original aim of such instruments) [3].
Atomic Scale Characterization of Oxygen Vacancy Ordering in Oxygen Conducting Membranes By Z-Contrast IMAGING and EELS
Authors: Klie RF , Browning ND 
Published: July 2020

Abstract
Mixed conductors have been the focus of many studies in the last decade, leading to a detailed understanding of many of the macroscopic bulk properties of these materials. in particular, although the reduced low temperature phase in rare earth perovskite oxides is commonly explained in terms of ordered brownmillerite structured micro domains, its transition to the high temperature phase remains elusive. in this presentation an investigation of (La, Sr)FeO3, prepared under different reducing conditions through correlated atomic resolution annular dark field imaging and electron energy loss spectroscopy will be shown.
We investigate the (La, Sr)FeO3 material by atomic resolution Z-contrast imaging and EELS using a 200 keV STEM/TEM JEOL2010F with a post column GIF. The combination of these techniques allows us to obtain direct images from the atomic structure of the bulk sample and to correlate this with the atomically resolved EELS information. In-situ heating of the material in a heating double tilt holder in the microscope columns allows us to simulate the highly reducing operating conditions for this oxygen conducting membrane material.
Determination of the Width of the GaN/AlxGa1-xN Heterointerface Using EELS
Authors: Mkhoyan KA , Alldredge ES , Silcox J , Ashcroft NW 
Published: July 2020

Abstract
It is known that wurtzite III-V nitrides are highly polarized in the c-direction, which is usually the growth direction. This polarization (spontaneous and piezoelectric) in GaN/AlxGa1-xN heterostructure field effect transistors (HFET) results in high carrier concentrations at the interfaces, in addition to the large conduction band offset. This high-density 2D electron gas formed at a GaN/AlxGa1-xN heterointerface in its turn increases the mobility of the heterostructure. Therefore, questions about the measurement of the physical width of a GaN/AlxGa1-xN interface and the calculation of its effects on the physical characteristics of devices naturally arise. Since the electrical field distribution, as well as the location and density of the 2D electron gas, depends on the width of the GaN/AlxGa1-xN heterointerface, accurate determination of the width is critical.
Measurements with high spatial resolution EELS using transmission electron spectroscopy with a ∽2Å focused electron beam permits atomic-level studies of such specimens.
Quantitative Measurement of Compositional Enrichment in Strained Alloy Quantum Dots
Authors: Crozier PA , Catalano M 
Published: July 2020

Abstract
High spatial resolution information on the structure and composition of semiconductor quantum dots is necessary to relate microstructure to macroscopic electron-optical properties [1]. Scanning transmission electron microscopy (STEM) combined with electron energy-loss spectroscopy (EELS) can be used to determine the elemental composition of nanometer-sized particles. Applying these techniques to quantum dots is challenging because the dot nucleates on a very thin wetting layer of similar composition and is embedded in a matrix. Here we present a strategy to extract absolute compositional information on InGaAs dots. The method relies on modeling both the dot shape and the electron probe profile.
Samples were prepared by depositing four monolayers of In0.5Ga0.5As onto a GaAs substrate giving a nominal wetting layer thickness of 1.2 nm [2]. STEM was performed on a Vacuum Generator's HB501 equipped with a GATAN parallel electron energy-loss spectrometer. An ES Vision system was used to acquire spatially resolved electron energy-loss spectra from the wetting layer and the quantum dots.
Extraction of Quantitative Magnetic Data Using Transmission Lorentz Microscopy
Authors: Chapman J N 
Published: July 2020

Abstract
The study of magnetic thin films by Lorentz microscopy in the transmission electron microscope (TEM) is a well-established technique. However, in many instances, images are recorded with the specimen in its as-grown state or in a single remanent state following application of a magnetic field outside the microscope. Although such images can provide valuable information, they rarely produce insight into the mechanism by which the magnetic material reverses nor do they show the magnetic structures that form during the reversal process. Furthermore, it is not possible to determine, for example, the field range over which a reversal takes place. Given the importance of such elements for magnetic sensing and storage applications, there is considerable incentive to develop techniques which not only yield the magnetisation loop for an individual element but which reveal how the spatial distribution of magnetisation evolves as a function of field.
Fluctuation Microscopy in the STEM
Authors: Voyles P M , Muller D A 
Published: July 2020

Abstract
Fluctuation microscopy is an electron microscopy technique sensitive to medium-range order (MRO) in disordered materials. It has been applied to study amorphous germanium and silicon, leading to the conclusion that these materials exhibit more MRO than the conventional continuous random network model for their structure.
As originally proposed by Treacy and Gibson, fluctuation microscopy utilizes mesoscopicresolution (1.5 nm) hollow-cone dark field (HCDF) imaging in a TEM. The normalized variance of such images,

is a measure of the magnitude of fluctuations in the diffracted intensity from mesoscopic volumes of the sample and is sensitive to MRO via the three- and four-body atom distribution functions. Studying V as a function of the diffraction vector magnitude k gives information about the degree of MRO and the internal structure of ordered regions. V as a function of the inverse resolution Q gives information about the characteristic MRO length scale.
A 2-2-2 200kv Field Emission STEM/TEM System
Authors: Boyes E D , Ringnalda J , Stam M A J van der , Fliervoet T F , Cappellen E Van 
Published: July 2020

Abstract
In many new application areas it is necessary to combine atomic resolution imaging with atomic level chemical and crystallographic analysis. The new applications include microbiology, nanotubes, smart materials and sensor initiatives, and the myriad semiconductor fields. Along with these there are many other valuable applications in older and more established technologies such as chemicals, catalysis, pigments and construction materials for chemical plants, airplanes, pipelines, power generation, and other aspects of societal infrastructure. Analysis down to the atomic level will help to solve recalcitrant problems and open up some reluctant opportunities in these fields. They can be very effective in resolving important and long standing issues with huge potential monetary and societal costs and benefits. Key aspects of environmentally sensitive corrosion and pollution control may also require the support of similarly sophisticated imaging and microanalysis.
We think the capabilities of a new generation high performance instrument should include atomic resolution coherent TEM imaging and also incoherent atomic number (Z) contrast high angle annular dark field (HAADF) STEM imaging.
Quantitative Characterization of Internal Boundaries — What Can Be Achieved with Electron Microscopy?
Authors: Elsasser Christian , Rühle Manfred 
Published: July 2020

Abstract
Internal boundaries in crystalline microstructures, like polycrystals, thin-film or multi-layer composites, essentially control many important material properties and physical phenomena, such as mechanical deformation and fracture, transport processes or phase transformations. This influence is originating from the local atomistic and electronic structures at the boundaries. Hence, for a. science-based technological design and optimisation of structural and functional materials it is of paramount importance to characterize and understand the structure, chemistry and bonding at interfaces.
Transmission electron microscopy (TEM) has matured to one of the most successful experimental approaches for the analysis of extended structural defects like dislocations and interfaces. This presentation discusses scientific and technological ingredients of TEM for quantitative characterisations on the microscopic level. For selected model cases of internal interfaces it illustrates recent achievements of both experiment and theory. A variety of interface properties and corresponding TEM techniques for their characterisation are summarized in TABLE 1.
The Use of Moiré Patterns in TEM Images to Measure Precipitate Composition in Al-Si-Ge Alloys
Authors: Radmilovic V , Mitlin D , Hinderberger S , Dahmen U 
Published: July 2020

Abstract
Moiré patterns are commonly formed in multiphase system when diffracting planes of similar spacing and orientation lead to interference effects. They can be used experimentally to evaluate the stress distribution in materials [1], to analyze orientation relationships and latttice strain in diffraction contrast microscopy, or, combined with the related geometrical phase technique, to analyze displacements in high resolution lattice images [2,3]. The interpretation of moiré fringes is often not straightforward due to the elastic interaction between the crystals at the interface and the dynamical nature of electron diffraction [4]. However, if the two lattices are fully relaxed, or if a small precipitate crystal is embedded in a large matrix, moiré patterns can give a simple and direct measure of orientation and lattice constants. in the present work, the moiré technique has been applied to the quantitative analysis of lath-shaped Ge or Ge-Si precipitates in Al with the aim to determine the composition (the Si:Ge ratio) from the lattice parameter indicated by the moiré fringes.
Quantitative Analysis of Interface Structure by HRTEM
Authors: Ernst Frank 
Published: July 2020

Abstract
The development of ‘quantitative’ high-resolution transmission electron microscopy (QHRTEM) has led to considerable progress in analyzing and understanding the atomistic structure of grain boundaries and heterointerfaces, which often control relevant macroscopic properties of materials. The following results of recent experimental studies and the comparison of these results with atomistic modeling demonstrate the strength of QHRTEM:
1.Grain Boundaries in SrTiO3. Some technical applications of SrTiO3 ceramics rely on special electric properties of this material, which originate from segregation of electrically active point defects to grain boundaries. QHRTEM can substantially contribute to understanding the correlation between the atomistic structure of grain boundaries and the segregation of point defects to these interfaces. As an example for a grain boundary structure solved by QHRTEM, FIGs. la and b present an experimental HRTEM image of the Σ= 3, (111) grain boundary in SrTiO3 and the corresponding atomistic structure as obtained by QHRTEM.
Optical Proprties of Tin Thin Film Obtained by Applying a Near Free Elctron Aproximation Using The Eels in Transmission Mode
Authors: González-Valenzuela C , González R , Espinosa-Magaña F , Martínez-Sanchez R , Duarte-Möller A 
Published: July 2020

Abstract
A TiN thin film was grown by the DC-Sputtering technique was characterized by EELS spectroscopy in order to obtain the optical quantities, ε1,ε2 and the refractive index η. Optical properties were obtained analyzing the low loss window located at an energy less to 50 eV respect to the elastic peak. A primary energy of 200 keV and a spot size of 440 nm with an average acquisition time of 5 min were used. The optical properties were calculated using the Kramers - Kronig relations.
Figure 1 shows the PEELS spectra in the low loss region for TiN thin film. As we can see, the most prominent plasmon loss peak characterizing TiN appears at an energy loss of 24 eV. The origin of the loss peak located at 17 eV is interpreted as surface plasmon. in order to obtain a better approximation, we use a near-free electron model and we have compared with the respective optical quantities calculated with the conventional formalism.
Quantitative Evaluation of The Chemical Composition of γ-γ’Interfaces in Ni Superalloys
Authors: Calderon H A , Benyoucef M , Clement N 
Published: July 2020

Abstract
The excellent mechanical properties of Ni based superalloys depend upon the presence of γ’ particles (LI2 structure). Their volume fraction, spatial distribution and size determine the mechanical strength of these alloys. Ni alloys for technological applications make use of large volume fractions of precipitates where processes of coarsening and coalescence take place during service leading in some cases to deterioration of properties. Addition of different alloying elements prevents accelerated coalescence by retarding diffusion and thus improving the mechanical properties of such alloys. Coalescence can also take place under the influence of an applied stress leading to the formation of rafts of the y' phase. For example the microstructure changes during creep deformation, depending on the alloy composition, with the corresponding formation of dislocation networks and rafts of different morphologies [1]. The γ-γ’ interfaces are also different depending on the alloy composition and most likely to the local distribution of alloying elements and their strain fields.
Grain Boundary Structure Analysis of Covalent Bonding Materials by Atomic Resolution Transmission Electron Microscopy
Authors: Ichinose Hideki , Sawada Hidetaka , Takuma Eriko , Saito Hideo 
Published: July 2020

Abstract
Grain boundaries of covalent bonding materials such as silicon, germanium and SiC require rather physical consideration than that of geometry to discuss the result of their electron microscopic observation. Dangling bond, for example, is expected least in number in the stable boundary (least dangling bond rule). [1][2] in practice, further precise consideration must be done both in geometry and in physics in the covalent bonding materials boundary. in the present study, geometrical discussion is combined together with that of the atomic bonding about diamond, SiC and ZnO grain boundaries. Chemical structure image of the modern high-voltage transmission electron microscope enabled to do it. An asymmetrical Σ3 boundary of diamond and a 6H-SiC boundary with 70.5 degree rotation are mainly observed.
The sliced specimen, 0.3mm in thickness, was mechanically thinned down to 0.02 mm and was finally polished using an argon ion milling. Final thickness of the specimen was estimated to be 3 nm in the region close to the edge of the small hole.
Hrem Observation of the Relaxation of Grain Boundaries in Au At Their Intersection with Free Surfaces
Authors: Radetic T , Dahmen U 
Published: July 2020

Abstract
Grain boundaries in fee metals with low stacking fault energy are known to undergo extended relaxations that can at times lead to a thin layer of a different structure. in Cu, for example, it has been found that Σ3{112}} boundaries relax into a 9R phase or even a bec phase. in this work, we have used high resolution electron microscopy to investigate the atomic structure of Σ99 grain boundaries in mazed bicrystal films of Au. On {001} Ge single crystal substrates, Au bicrystals can be grown in two equivalent {110} orientation variants, related to each other by a 90° rotation about the surface normal. There is equal probability to nucleate either orientation variant in early stages of film formation and since there is no reason for preferential growth, the morphology of the bicrystal film consists of many grains in only two orientations. All grain boundaries are of the type Σ99 and display tilt character.
Thin films 10-200nm thick were grown by physical vapor deposition on {001} Ge substrate at 280°C and followed by annealing at 200°C to relieve stresses.
Quantitative Electron Holography - From The Basis of Dynamical Interaction to Holographic Materials Analysis
Authors: Brand Karin , Guo Chengshan , Lehmann Michael , Lichte Hannes 
Published: July 2020

Abstract
Quantitative analysis of a structure means to determine which atoms are where. The where is restricted by the lateral resolution, and the which is related to the sensitivity against differences of the atomic species. Electron holography is on the move to tackle both questions.
• where - Lateral Resolution Electron holography has surmounted conventional electron microscopy in that it has reached atomic resolution both in the amplitude and phase images: with our CM30FEG/UT Special Tuebingen electron microscope, the information limit of 0.09nm and the pixel number of the 2048_ - CCD camera allow to take holograms with image details smaller than 0.095nm; the quality of correction of the aberrations allows an interpretable resolution approaching 0. lnm both in amplitude and phase [1].
• which - Phase Detection Limit (PDL) The phase detection limit describes the minimum phase difference detectable well above a given noise level.