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JPCRD has also published about 100 articles with thermochemical data and a similar number with atomic energy levels (and related data). JPCRD is a joint effort between the National Institute of Standards and Technology (NIST, which prior to 1988 was the National Bureau of Standards, NBS) and the American Institute of Physics (AIP). We hope JPCRD can continue to be a place where scientists and engineers can turn to be guided to data that are well-documented and of the best available quality - in other words, reference data. [Extracted from the article]

X-ray fluorescence (XRF) spectroscopy is a frequently used technique for the chemical analysis of materials due to several advantages such as its almost nondestructive character. Subjects of this report are investigations of the pyroelectric effect with regard to its application for the generation and acceleration of x-rays and a successive usage of radiation for XRF in materials science. In order to answer questions concerning the intensity of primary radiation and of fluorescence radiation, this paper contains several experimental investigations. Different setups and measurements have been used to increase intensity. Emission behavior of electrons has been characterized using measurements of electron current in a target positioned in front of a pyroelectric crystal as a function of the temperature of the crystal and time. Radiation has been coupled out, and its dose equivalent rate has been measured. This allowed the optimization of the working pressure of the residual gas surrounding the crystal in an evacuated atmosphere (rarefied air). It has been shown that a vacuum pressure of approximately 5 × 10−1 Pa allows the generation of radiation with high intensities. Different target materials have been compared due to the intensity of excited fluorescence radiation of a sample by using an energy dispersive radiation detector. A qualitative and quantitative analysis of elements contained in the sample has been proven to be feasible. A possible application of the radiation for imaging has been investigated. [ABSTRACT FROM AUTHOR]

The theoretical (ideal) strength is the upper strength limit that any solid can withstand. Estimation of the theoretical strength of materials is vital for their applications. In the materials science field, the Griffith theory is the most widely used criterion for estimating the theoretical strength of materials, which sets an upper bound strength of ∼E/9. In addition, Frenkel and Orowan–Polanyi's derivation from the force–displacement relationship using the sinusoidal correlation also gives a similar value of ∼E/10. Recently, with the improved quality of fabricated samples, people have reported the possibility of reaching or exceeding the theoretical strength. In this work, first-principles calculations based on density functional theory (DFT) are used to study the theoretical strength of four representative materials (diamond, c-BN, Cu, and CeO2) under uniaxial tensile loading along the low-index crystallographic directions. The results demonstrate that the theoretical strength of materials exhibits strong anisotropy. It is found that the ideal strength calculated by DFT is larger than the ideal strength predicted by Griffith theory or the approximate value of E/10 in all the four materials along some specific directions. This discrepancy is explained by the analysis of the fracture mechanism. In addition, based on the stability analysis of thermodynamical systems, the strength criterion based on the energy–strain relation was established, which is verified by the DFT results. [ABSTRACT FROM AUTHOR]

Spreitzer I et al. i [96] provide a research update on the growth of ferroelectric oxide thin films on silicon, with a particular view toward their applications in piezoelectric micro electromechanical systems (MEMS), electro-optic devices for communications applications, and catalysis and a consideration of the complexities of the silicon-ferroelectric interface. The favored theory for oxide ferroelectrics is the soft-mode theory, and here, we have a perspective by Kamba[79] discussing the results of broadband dielectric, THz, and IR spectroscopic investigations of soft-mode phenomena in H-bonded ferroelectrics, BaTiO SB 3 sb , relaxors, and multiferroics. Domains are also of considerable interest in antiferroelectric materials, and An I et al. i [118] discuss the hierarchical nature of domains in PZT crystals with only 2 at. % Ti, close to the antiferroelectric PbZrO SB 3 sb composition, showing how this forms in the intermediate ferroelectric state and have a significant impact on the materials' physical properties. Subsequently, there has been shown to be a wide range of metal organic complex ferroelectrics, as reviewed by Hang I et al. i [123] In this collection, we have an overview by Yao I et al. i [124] of the potential for bandgap engineering in hybrid organic-inorganic perovskite (HOIP) ferroelectrics such as (MDABCO)(NH SB 4 sb )I SB 3 sb [MDABCO = I N i -methyl I N i '-diazabicyclo(2.2.2)octonium], with the potential for linking the excellent characteristics of the new perovskite materials for solar cells, such as methylammonium lead iodide (MAPbI SB 3 sb ),[125] with the photovoltaic effects seen in ferroelectrics. [Extracted from the article]

GHz phonons have a significant contribution to thermal transport at sub-Kelvin temperatures, and the authors, thus, probe the thermal conductance of the proposed PnC at low temperatures. At the small scale, thermocrystals promise the control of thermal conductance via coherent phonon and heat transport engineering. Over the past three decades, phononic crystals (PnCs) have attracted scientific interest by demonstrating a variety of unique manipulations of sound and elastic wave propagation through control of wave dispersion by Bragg scattering. [Extracted from the article]

The carbon 1s photoelectron spectrum is the most widely fit and analyzed narrow scan in the x-ray photoelectron spectroscopy (XPS) literature. It is, therefore, critically important to adopt well-established protocols based on best practices for its analysis, since results of these efforts affect research outcomes in a wide range of different application areas across materials science. Unfortunately, much XPS peak fitting in the scientific literature is inaccurate. In this guide, we describe and explain the most common problems associated with C 1s narrow scan analysis in the XPS literature. We then provide an overview of rules, principles, and considerations that, taken together, should guide the approach to the analysis of C 1s spectra. We propose that following this approach should result in (1) the avoidance of common problems and (2) the extraction of reliable, reproducible, and meaningful information from experimental data. [ABSTRACT FROM AUTHOR]

Microfluidics is a relatively novel interdisciplinary research area with broad applications in chemistry, physics, material science, and biology. Despite the rapid growth of the field, students' exposure to microfluidic technologies is still limited and often insufficient to appreciate the advantages over other commonly used technologies. To this end, we designed a five-day course, "Microfluidics for microbial ecology," in which students with very different backgrounds learn the basics of microfluidic technologies and sample a range of applications in microbial ecology. The course was created for Master and Ph.D. students interested in applying microfluidics to their research and, therefore, followed an application-oriented approach. The presentation of critical aspects of fluid flow phenomena at the microscale and an outline of the advantages and constraints of the technology provide students with the background to design and perform microfluidics-based experiments. In order to improve the effectiveness of learning in a class with diverse interests and backgrounds, two active learning exercises were implemented. The first comprised the design of an individualized microfluidics experiment in parallel with the lectures: students were guided to apply each module to their personalized application and discuss it in groups. The second was a group experimental activity, in which students jointly set up, performed, analyzed, and presented a microfluidics-based experiment. Given the multidisciplinary teaching context, the course was able to foster common conceptual ground and promote discussion among students. This application-oriented approach built upon experimental activities and in-class discussion is well suited to promote learning in a technology-related subject such as microfluidics. [ABSTRACT FROM AUTHOR]

The theoretical analysis and the experiment of perturbation techniques to the quantitative measurement of electric field characteristics in a 94 GHz extended interaction resonant cavity (EIRC) are described. Parameters such as the observed reflection coefficient (S11) and resonant frequency at the disturbance point can be adopted to determine the Q-factor, relative electric field intensity, and distribution of the EIRC. In the experiment stage, the frequency deviation characteristics of the tested EIRC under the influence of the metallic sphere are consistent with the simulation results, and the relative error of the frequency deviation is 4.40%. This provides an effective solution for studies of the performance monitoring of millimeter–submillimeter-wave electronic devices and the exploration of high-frequency material science. [ABSTRACT FROM AUTHOR]

Structure–property relationships play a central role in condensed matter physics, chemistry, and materials science. However, the problem of predicting the structure of a material, given its chemical composition, remains immensely challenging. Here, we review some of the progress that has been made in this area for both crystalline materials and atomic clusters. Early work consisted of heuristic rules-of-thumb or structure maps using descriptors that were obtained largely by inspection. Increasingly, these approaches are being expanded to use descriptors that have been obtained by applying machine learning techniques to big data containing information from the experiment and/or first principles calculations. Improved techniques for global optimization in the multi-dimensional coordinate space have also led to major advances in the field. [ABSTRACT FROM AUTHOR]

We introduce a wide field hyperspectral microscope using the Fourier-transform approach. The interferometer is based on the translating-wedge-based identical pulses encoding system, a common-path birefringent interferometer which combines compactness, intrinsic interferometric delay precision, long-term stability, and insensitivity to vibrations. We describe two different implementations of our system, which maximize fringe visibility and phase invariance over the field of view, respectively. We also demonstrate that our system can be installed as an add-on in a commercial microscope. We show high-quality hyperspectral fluorescence microscopy from stained cells and powders of inorganic pigments in the spectral range from 400 to 1100 nm, proving that our device is suited to biology and materials science. We also introduce an acquisition method that synthesizes a tunable spectral filter, providing band-passed images with the measurement of only two maps. [ABSTRACT FROM AUTHOR]

The mask shadowing effect is a unique phenomenon caused by a mirror-based mask structure and an oblique incident angle of light in the extreme ultraviolet lithography process. This results in a horizontal-vertical (H-V) bias, an ellipticity in the contact hole pattern and, eventually, a patterning limit and critical dimension (CD) nonuniformity. Reducing the absorber thickness is the most effective method to minimize the mask shadowing effect, but this can deteriorate the mask image contrast. In this paper, an attenuated phase shift mask (PSM) is proposed as a potential method for extending the patterning limit to below 16 nm. By applying Mo as a phase shift layer, which has a refractive index (n) similar to that of the TaN absorber but with a lower absorption value, thin attenuated PSMs with various reflectivity values were obtained by controlling the Mo thickness. The proposed PSM consists of a 16.5-nm-thick TaN absorber layer and a 24-nm-thick Mo phase shifter on 2-nm-thick Ru-capped Mo/Si multilayers. This attenuated PSM results in 17.98% and 27.52% reductions in the mask error enhancement factor as well as 3.65 and 1.84 nm reductions in the H-V CD bias compared with the conventional binary intensity mask with a 70-nm-thick TaN absorber for the 22 nm line and space 1:1 vertical dense pattern under 0.25 and 0.33 numerical aperture illumination conditions, respectively. Moreover, a 10%-12% improved image contrast was obtained with 11%-17% reflectivity on the absorber stack, which corresponds to a 24-29 nm Mo thickness under 0.25 NA illumination conditions. [ABSTRACT FROM AUTHOR]

The authors have found that patterning polyimide coatings containing organosilane adhesion promoter using pure oxygen plasma resulted in a thin silicon-rich residue layer. They show in this paper that adding small amounts of fluorine-containing gas to the etching gas mixture is necessary in order to achieve residue-free polyimide plasma etching. They report residue-free plasma etching of polyimide coatings with both isotropic and anisotropic profiles, using either metal or oxide hard masks. These etching methods are however not sufficient for the fabrication of high density metal filled vias in 10 μm thick polyimide coatings. In order to improve the metal step coverage over the vias while keeping the pitch as small as possible, the authors have developed a two-step etching recipe combining both isotropic and anisotropic profiles, resulting in wine-glass shaped vias. [ABSTRACT FROM AUTHOR]

This paper investigates the negative bias instability (NBS) and positive bias instability (PBS) of titanium oxide (TiOx) thin-film transistors (TFTs) with different annealing temperatures. Structural analyses suggested that TiOx films annealed at 450 and 550 °C had average grain sizes of 200 and 400 nm, respectively. A TiOx TFT annealed at 550 °C exhibited respective threshold voltage (Vth) shifts of only -1.4 and 10.2 V under NBS and PBS conditions. The origin of the instability was found to be a charge trapping mechanism caused by different grain sizes, boundaries, and changes in band edge states below the conduction band, which acted as electron and hole trap sites. [ABSTRACT FROM AUTHOR]

Diffusion, transport of mass in response to concentration and thermal energy gradient, is an important transport property, vital in material science and life science. In the present work, we have studied about the diffusion of zwitterion glycine, zwitterion diglycine and zwitterion triglycine in SPC/E model of water using classical molecular dynamics. Self and binary diffusion coefficients of aqueous solution of these molecules have been estimated using Einstein's method. Our results agree with experimental data reported in literatures. Temperature dependency of diffusion of glycine in water has been explored using estimated values of self and binary diffusion coefficients at four different temperature. Effects of peptide bond formation in diffusion has been studied using peptide chain composed of up to three monomers of glycine. The system-size dependence of diffusion coefficient has been studied and the shear viscosity of solvent and system has been calculated. Also, the diffusion coefficient of zwitterion glycine in other water model TIP4P/2005 has been estimated. The structure of the system has been analyzed using radial distribution function of different atoms. [ABSTRACT FROM AUTHOR]

Actively controllable material properties are desirable for applications in materials science and microwave engineering. We design and fabricate a magnetically-coupled metamolecule with ferrite for X-band microwave frequencies that shows tunable responses to external magnetic fields. When compared with the metamolecule's magnetic Mie resonance, superior field sensitivity is observed in the vicinity of the Fano resonance through analysis of the transmission spectra. The mechanism is investigated by emulating the field distributions, and the phenomenon is attributed to specially coupled magnetic dipoles. The simulation results are verified experimentally. This work substantiates the metamaterial's enhanced electromagnetic properties for potential application to tunable microwave devices. [ABSTRACT FROM AUTHOR]

In 1997, Nobel Laureate John B. Goodenough and his team reported lithium iron phosphate (LiFePO SB 4 sb ) as a promising cathode for lithium-ion batteries (LIBs) with abundant raw materials, low cost, and environmental friendliness.[1] In particular, with the widespread use of energy storage devices in electric vehicles, portable devices, and home and electric grid-scale battery storage, there is an urgent call for abundant and non-toxic materials. 34, 2110109 (2022).10.1002/adma.202110109 5 R. C. Massé, E. Uchaker, and G. Cao, "Beyond Li-ion: Electrode materials for sodium- and magnesium-ion batteries", Sci. Mg-Sn alloys suffer a large volume change during cycling as an anode for rechargeable magnesium batteries (RMBs), causing poor Coulombic efficiency and rapid capacity fading. [Extracted from the article]

These are exciting times formaterials science--a field which is growingmore rapidly than any other physical science discipline. More than ever, the field is providing the vital link between science and engineering, between pure and applied. But what is the subject's definition and why is the field ballooning? I address these questions in the context of how APL Materials intends to play a role in advancing this important field. My introspective focus arises as we approach the first year anniversary of APL Materials. [ABSTRACT FROM AUTHOR]

Our ability to collect "big data" has greatly surpassed our capability to analyze it, underscoring the emergence of the fourth paradigm of science, which is datadriven discovery. The need for data informatics is also emphasized by the Materials Genome Initiative (MGI), further boosting the emerging field of materials informatics. In this article, we look at how data-driven techniques are playing a big role in deciphering processing-structure-property-performance relationships in materials, with illustrative examples of both forward models (property prediction) and inverse models (materials discovery). Such analytics can significantly reduce time-to-insight and accelerate cost-effective materials discovery, which is the goal of MGI. [ABSTRACT FROM AUTHOR]

San Roman I et al. i [4] review the use of graphene nanostructures and discuss the fundamental relationships between device geometries, materials properties, and performance of the next generation bioelectronic devices. Jia I et al. i [5] demonstrate an electrochemical device that uses Ag/AgCl contacts to achieve precise spatiotemporal control of chloride ion concentration in solution and review their recent progress on using bioelectronics to control pH. Modern electronics and materials science are bringing revolutionary advances to biointerface design and are shattering the limits of what is possible in the areas of biomedical diagnostics and sensing, neuroscience, and prosthetics. [Extracted from the article]

First principles calculations have been performed to study the mono-vacancy formation energies and electronic properties of M2AlC (M = V and Nb) compound. The results show that the M mono-vacancy has a maximum formation energy. While the C mono-vacancy has a minimum formation energy, which means that the C mono-vacancy is the energetically most favorable in M2AlC. The d-electrons of M element contribute most to the DOS of M2AlC around the Fermi level, it implies that the conductivity of M2AlC comes from the transition metal M. The M-C bond is stronger than the M-Al bond, which is caused by the strong hybridization energy peak between M and C atom. In addition, the M-C bond is weaken in the presence of the M or C mono-vacancy. The cell volumes are reduced when the mono-vacancy is formed. These results help us to understand the origin of the defect-related properties and phase stability of V2AlC and Nb2AlC under extreme environment. [ABSTRACT FROM AUTHOR]

Bioinspired poly(catecholamine) based coatings, mostly "polydopamine," were conceived based on the chemistry used by mussels to adhere strongly to the surface of stones and wood in water and to remain attached to their substrates even under conditions of strong shear stresses. These kinds of films can in turn be easily modified with a plethora of molecules and inorganic (nano)materials. This review shows that poly(catecholamine) based coatings are an ideal film forming method for applications in the field of biomaterials. It is written from a physicochemical and a materials science perspective and discusses optical, chemical, electrochemical, and mechanical properties of polydopamine films. It further demonstrates that a better understanding of the polydopamine film deposition mechanism is warranted to improve the properties of these coatings even further. [ABSTRACT FROM AUTHOR]

Single-molecule-sensitive microscopy and spectroscopy are transforming biophysics and materials science laboratories. Techniques such as fluorescence correlation spectroscopy (FCS) and single-molecule sensitive fluorescence resonance energy transfer (FRET) are now commonly available in research laboratories but are as yet infrequently available in teaching laboratories. We describe inexpensive electronics and open-source software that bridges this gap, making state-of-the-art research capabilities accessible to undergraduates interested in biophysics. We include a discussion of the intensity correlation function relevant to FCS and how it can be determined from photon arrival times. We demonstrate the system with a measurement of the hydrodynamic radius of a protein using FCS that is suitable for the undergraduate teaching laboratory. The FPGA-based electronics, which are easy to construct, are suitable for more advanced measurements as well, and several applications are described. As implemented, the system has 8 ns timing resolution, can control up to four laser sources, and can collect information from as many as four photon-counting detectors. [ABSTRACT FROM AUTHOR]

We study numerically absorption optical spectra of n-doped InAs/In015Ga085As/ GaAs quantum dot-in-a-well systems. The absorption spectra are mainly determined by the size of a quantum dot and have weak dependence on the thickness of quantum well and position of the dot in a well. The dot-in-a-well system is sensitive to both in-plane and out-of-plane polarizations of the incident light with much stronger absorption intensities for the in-plane-polarized light. The absorption spectrum of in-plane-polarized light has also a multi-peak structure with two or three peaks of comparable intensities, while the absorption spectrum of out-of-plane polarized light has a singlewell-pronounced peak. [ABSTRACT FROM AUTHOR]

Density functional-pseudopotential calculations were performed to study the effects of hydrogen doping and oxygen vacancy, both individually and together, on the electronic structure and stability of (001) surface of TiO2 in the anatase phase. Based on our calculations, O/Ti termination is the most stable one, and it appears that pstates of deep and surface O atoms and d-orbitals of surface Ti atoms have roles in the valence band and, the conduction band comes from the d-orbitals of deep Ti atoms. Although, no considerable change was seen during H doping, a mid-gap state appeared below the conduction band in the O vacancy configuration. In the framework of ab-initio atomistic thermodynamics, we argue that the anatase TiO2 prefers a defected O layer termination in the [001] direction. The obtained electronic structures indicate thatHdoping in the bulk creates the empty mid-gap state belowthe conduction band and hence decreases the band gap of the system. This phenomenon may explain the enhanced photocatalytic activity of the anatase TiO2 (001) surface after hydrogenation. [ABSTRACT FROM AUTHOR]

Self-assembly SiO2 nanosphere monolayer template is utilized to fabricate nanopatterned sapphire substrates (NPSSs) with 0-nm, 50-nm, and 120-nm spacing, receptively. The GaN growth on top of NPSS with 0-nm spacing has the best crystal quality because of laterally epitaxial overgrowth. However, GaN growth from pattern top is more difficult to get smooth surface than from pattern bottom. The rougher surface may result in a higher work voltage. The stimulation results of finite-difference timedomain (FDTD) display that too large or too small spacing lead to the reduced light extracted efficiency (LEE) of LEDs. Under a driving current 350 mA, the external quantum efficiencies (EQE) of GaN-based LEDs grown on NPSSs with 0-nm, 50-nm, and 120-nm spacing increase by 43.3%, 50.6%, and 39.1%, respectively, compared to that on flat sapphire substrate (FSS). The optimized pattern spacing is 50 nm for the NPSS with 600-nm pattern period. [ABSTRACT FROM AUTHOR]

We measure the transverse velocity distribution in a thermal Sr atomic beam precisely by velocity-selective saturated fluorescence spectroscopy. The use of an ultrastable laser system and the narrow intercombination transition line of Sr atoms mean that the resolution of the measured velocity can reach 0.13 m/s, corresponding to 90 μK in energy units. The experimental results are in very good agreement with the results of theoretical calculations. Based on the spectroscopic techniques used here, the absolute frequency of the intercombination transition of 88Sr is measured using an optical-frequency comb generator referenced to the SI second through an H maser, and is given as 434 829 121 318(10) kHz. [ABSTRACT FROM AUTHOR]

We estimate the thickness and ordering temperature of an antiferromagnetic and passivation surface oxide through exchange bias coupling. The surface NiO, which is generated through the exposure of a Ni/Cu(001) surface to oxygen, is taken as a model system on which to perform the estimation. Since no exchange bias is found in the surface NiO/Ni/Cu(001), we have built a sandwich structure of NiO/n ML Ni/10 ML Co/Cu(001) to measure the n dependence of exchange bias. With n ≤ 2, a large exchange bias field is found above 300 K, which could be due to the direct contact between the oxides and the Co layer. With 3 ≤ n ≤ 6, a smaller exchange bias field is found with a blocking temperature of 190 K. This implies that the thickness of NiO is, at most, 3 ML. Discovering the thickness and ordering temperature of the surface NiO provides us to explore the potential applications by using surface NiO. [ABSTRACT FROM AUTHOR]

We report a formalism for the study of quasibound states, defined here broadly as those states having a connectedness to true bound states through the variation of some physical parameter. The theory admits quasibound states with real energies (stationary quasibound states) and quantum resonances within the same framework, and makes a clean distinction between these states and those of the associated continuum. The approach taken here builds on our earlier work by clarifying several crucial points and extending the formalism to encompass a variety of continuous spectra, including those with degeneracies. The theory is illustrated by examining several cases pertinent to applications widely discussed in the literature. The related issue of observing stationary quasibound states also is addressed. We argue that the Adiabatic Theorem of quantum mechanics not only establishes the criteria necessary for their detection, but also engenders a method for assigning to them a level width that is sufficiently distinct from that of quantum resonances so as to allow the two to be differentiated experimentally. [ABSTRACT FROM AUTHOR]

Effect of substrate rotation on anisotropy and domain structure for a thin ferromagnetic film has been investigated in this work. For this purpose Co films with 10 nm thickness have been prepared by sputtering with oblique angle of incidence for various substrate rotations. This method of preparation induces a uniaxial anisotropy due to shadow deposition effect. The magnetization reversal is studied by magneto-optic Kerr effect (MOKE) based microscope in the longitudinal geometry. The Co films prepared by rotating the substrate with 10 and 20 rpm weakens the anisotropy but does not completely give isotropic films. But this leads to high dispersion in local grain anisotropy resulting in ripple and labyrinth domains. It is observed that the substrate rotation has moderate effect on uniaxial anisotropy but has significant effect on the magnetization reversal process and the domain structure. [ABSTRACT FROM AUTHOR]

A novel gallium arsenide (GaAs) based micro-cooler design, previously analysed both experimentally and by an analytical Heat Transfer (HT) model, has been simulated using a self-consistent Ensemble Monte Carlo (EMC)model for a more in depth analysis of the thermionic cooling in the device. The best fit to the experimental data was found and was used in conjunction with the HT model to estimate the coolercontact resistance. The cooling results from EMC indicated that the cooling power of the device is highly dependent on the charge distribution across the leading interface. Alteration of this charge distribution via interface extensions on the nanometre scale has shown to produce significant changes in cooler performance. [ABSTRACT FROM AUTHOR]

Sagdeev's pseudo potential method is employed to study dust acoustic solitary waves in an unmagnetized plasma containing negatively charged dusts with non-thermal electron and ion. The range of parameters for the existence of solitary waves using the analytical expression of the Sagdeev potential has been found. It is observed that, depending on the values of the plasma parameters like ion to electron temperature ratio σ, non-thermal parameters β and γ , electron to ion density ratio μ, and the value of the Mach number M, both rarefactive and compressive solitary waves may exist. [ABSTRACT FROM AUTHOR]