Polycrystalline Plates Research Articles

Optical materials for IR fiber optics based on solid solutions of AgCl0.25Br0.75 – TlCl0.74Br0.26, AgCl0.25Br0.75 – TlBr0.46I0.54 systems

The development of optical materials, that are transparent from the visible to the far IR without absorption windows, including fiber optics materials, continues to be an urgent scientific problem, which is associated with high prospects for their application in wide-spectrum systems, IR and THz technology. This article is devoted to the development of materials based on the AgCl0.25Br0.75 – TlCl0.74Br0.26 and AgCl0.25Br0.75 – TlBr0.46I0.54 systems from constructing phase diagrams to synthesis of single crystals and optical ceramics and their transmission properties investigation. According to the results of studying the phase diagram of the AgCl0.25Br0.75 – TlCl0.74Br0.26 system, homogeneity regions of 0–7 mol. % and 95–100 mol. % TlCl0.74Br0.26 in AgCl0.25Br0.75, in which there are single-phase solid solutions with the structure Fm3m and Pm3 m, respectively, were obtained. In this diagram, regions of heterogeneity with a composition of 7–79 mol. % and 79–95 mol. % TlCl0.74Br0.26 in AgCl0.25Br0.75 and a mixture of two phases in the first region Fm3m and R-3, and in the second region Pm3 m and R-3 were found. Within the AgCl0.25Br0.75 – TlBr0.46I0.54 system's phase diagram, homogeneity regions with compositions of 0–15 mol. % and 92–100 mol. % TlBr0.46I0.54 in AgCl0.25Br0.75 and similar structures Fm3m and Pm3 m, respectively, were determined. This system also contains regions of heterogeneity with compositions of 15–36 mol. %. and 69–92 mol. % TlBr0.46I0.54 in AgCl0.25Br0.75 with phase composition Fm3m and R-3, and Pm3 m and R-3. In each system, compositions were selected from the homogeneity and heterogeneity regions, and samples of single crystals and two-phase ceramics were synthesized. For the AgCl0.25Br0.75 – TlCl0.74Br0.26 system, a single crystal with a composition of 3 mol. % TlCl0.74Br0.26 in AgCl0.25Br0.75 and two-phase ceramics of 7, 31, 86, 92 mol. % TlCl0.74Br0.26 in AgCl0.25Br0.75 were obtained. Single crystals 3, 6, 9, 92 mol. % TlBr0.46I0.54 in AgCl0.25Br0.75 and ceramics 32, 76 mol. % TlBr0.46I0.54 in AgCl0.25Br0.75 were synthesized in AgCl0.25Br0.75 – TlBr0.46I0.54 system. The samples are 35 ± 5 mm high and 10 ± 0.1 mm in diameter, and their color varies from yellow to orange depending on the composition. The transmittance ranges of all synthesized samples were investigated. The study was carried out on polycrystalline plates with a diameter of 15 ± 5 mm, thickness of 400 ± 5 μm, and surface roughness Ra = 0.2 μm. The crystallite size of the alloying phase R-3 in the optical ceramics was less than 100 nm. For AgCl0.25Br0.75 – TlCl0.74Br0.26 system materials, the transmission spectra covered the region from 0.4 to 55.0 μm. Materials based on the AgCl0.25Br0.75 – TlBr0.46I0.54 system showed transmission in the wavelength range of 0.49–60.0 μm. All materials are transparent in the wide region without absorption windows with a transparency level up to 79%. Thus, new optical materials based on the AgCl0.25Br0.75 – TlCl0.74Br0.26 and AgCl0.25Br0.75 – TlBr0.46I0.54 systems have been developed, which have a wide transmission range from the visible to the IR. This opens broad prospects for their use as an optical material for wide-spectrum devices, as well as IR fiber optics.

On the mechanism of rock fracture with tools made of hard alloys and polycrystalline superhard materials

When studying the process of rock fracture with tools equipped with polycrystalline superhard materials (PSHM) and hard alloys, the main regularities of the fracture mechanism, despite the significant differences in physical and mechanical properties of the used tool materials, are assumed to be identical. This approach not only reduces the efficiency of using the created rock-destroying tools, but also limits the scope of application of polycrystalline superhard materials. Experimental studies using various methods of obtaining information shown significant differences in the mechanism of rock fracture by hard alloys and polycrystalline superhard materials. The study of the zone of the pre-destroyed surface showed that when cutting rocks with PSTM, the process of destruction is carried out not only by the entire polycrystalline plate, but also by ridged diamond formed on the cutting edge and rear surface of the tool. At the same time ridged diamonds, when embedded in the rock, create high contact stresses and an additional network of microcracks interacting with microcracks formed due to the embedding of the entire cutting edge of the plate. The impact of two independent indenters simultaneously increases the zone of the pre-destruction layer in the rock mass, which leads to a more significant decrease in its strength and, as a consequence, to the intensification of the process of rock destruction by the PSTM tool. In case of wrong choice of PSTM application area and operation modes, errors in tool design and insufficient cooling, ridges are not formed on the cutting edge and back surface of the polycrystal. As a result, the polycrystalline insert works as a carbide insert and the efficiency of the PSHM tool is sharply reduced. The use of knowledge obtained as a result of the conducted research makes it possible to create tools equipped with diamond-hard-alloyed inserts, the wear resistance of which is dozens of times higher than that of similar tools made of hard alloy. For example, effective tools equipped with diamond-hard-alloyed inserts have been created and widely introduced into practice for rotary drilling of boreholes, degassing wells, anchoring of mine workings, saw stone cutting, drilling of abrasive permafrost soils and others. Keywords: polycrystalline diamonds cutters (PDC), hard alloys, pre-destruction zone, rock breaking tools, rock destruction.

Ferroelectric Ionic Molecular Crystals with Significant Plasticity and a Low Melting Point: High Performance in Hot‐Pressed Polycrystalline Plates and Melt‐Grown Crystalline Sheets

AbstractAmong ferroelectric crystals based on small molecules, plastic/ferroelectric crystals are currently receiving particular attention because they can be used as bulk polycrystals. Herein, we show that an ionic molecular ferroelectric crystal, guanidinium tetrafluoroborate, exhibits significant malleability and multiaxial ferroelectricity despite the absence of a plastic crystal phase. Powder samples of this crystal can be processed into transparent bulk crystalline plates either by press‐forming or by melt‐growing. The plates show high ferroelectric performance and related properties, demonstrating the largest hitherto reported spontaneous polarization for bulk polycrystals of small‐molecule‐based ferroelectrics. Owing to the ready availability of large‐scale materials and processability into various bulk crystalline forms, this ferroelectric crystal represents a highly promising functional material that will boost research on diverse applications as bulk crystals.

Ferroelectric Ionic Molecular Crystals with Significant Plasticity and a Low Melting Point: High Performance in Hot-Pressed Polycrystalline Plates and Melt-Grown Crystalline Sheets.

Among ferroelectric crystals based on small molecules, plastic/ferroelectric crystals are currently receiving particular attention because they can be used as bulk polycrystals. Herein, we show that an ionic molecular ferroelectric crystal, guanidinium tetrafluoroborate, exhibits significant malleability and multiaxial ferroelectricity despite the absence of a plastic crystal phase. Powder samples of this crystal can be processed into transparent bulk crystalline plates either by press-forming or by melt-growing. The plates show high ferroelectric performance and related properties, demonstrating the largest hitherto reported spontaneous polarization for bulk polycrystals of small-molecule-based ferroelectrics. Owing to the ready availability of large-scale materials and processability into various bulk crystalline forms, this ferroelectric crystal represents a highly promising functional material that will boost research on diverse applications as bulk crystals.

Optical properties of the AgBr – AgI system crystals

The article is devoted to the study of the AgBr – AgI system crystals optical properties in the composition range from 0 to 36 mol. % AgI in AgBr. The study was carried out on polycrystalline plates obtained from single crystals. The refractive index at the crystal' intrinsic absorption edge, the dependence in the refractive index change on the composition and wavelength (from 3.0 to 14.0 μm), the refractive indices' imaginary parts characterizing the attenuation of light in the material and the photostability were determined. All parameters are of key importance for fiber optic products modeling and design over a wide spectral range.

Advances in strain engineering on oxide heteroepitaxy

Advances in strain engineering on oxide heteroepitaxy

Time Transient of Calcium and Phosphate Ion Adsorption by Rutile Crystal Facets in Hanks' Solution Characterized by XPS.

For the elucidation of the mechanism of calcium phosphate formation on commercially pure titanium (CP Ti) in the human body, rutile TiO2 single crystal plates with (001), (110), and (111) facets, namely, TiO2(001), TiO2(110), and TiO2(111), and polycrystalline plates (TiO2(poly)) were immersed in a simulated body fluid, Hanks' solution (Hanks), for 100-105 s, and the adsorption of calcium and phosphate ions was precisely characterized employing X-ray photoelectron spectroscopy (XPS). Previously published CP Ti data were used for comparison. Prior to immersion in Hanks, oxygen content was more than twice as high as that of titanium due to the existence of hydroxyl groups and water on the oxides. After immersion in Hanks, the composition and chemical state of the TiO2 substrates remained unchanged. Among the electrolytes contained in Hanks, only calcium and phosphate ions were adsorbed by and incorporated onto TiO2 surfaces. Adsorption of calcium ions onto rutile did not exhibit any systematic increase of calcium with immersion time except TiO2(poly). Adsorption of phosphate ions was initially constant, followed by an increase with the logarithm of immersion time. The adsorption rate of phosphate ions decreased in the following order: TiO2(001), TiO2(poly), TiO2(111), CP Ti, and TiO2(110). The coordination number and band gap of each crystal facet of rutile is important for the adsorption and incorporation of phosphate ions. Regular calcium phosphate formation on CP Ti is possibly enabled by the surface oxide film, which consists chiefly of amorphous TiO2. However, calcium phosphate formation kinetics on CP Ti differed from those on the TiO2 crystalline phase. These findings may further the understanding of CP Ti hard tissue compatibility.

The optical transparency investigation of crystals based on the AgHal – TlHal solid solutions systems in the terahertz range

Abstract This article examines the transmission spectra of crystals based on the AgCl − AgBr, AgBr − TlI, AgBr − TlBr0.46I0.54 (KRS-5), AgBr − AgI systems in the visible, infrared, and terahertz ranges. We've determined the optical characteristics in the terahertz range for polycrystalline plates obtained by hot embossing based on silver and thallium halides' solid solutions. As a study result, silver and thallium (I) halides have demonstrated competitive transmission characteristics both in the visible and infrared spectra also in the THz frequency range. The transmission range for crystals of the AgCl − AgBr system was 0.45–30.0 μm (9.9–666.2 THz) and 250–6000 μm (0.05–1.19 THz) with optical transparency reaching 78%, for crystals of the AgBr − AgI, AgBr − TlI, AgBr − TlBr0.46I0.54 systems, 47.0–60.0 μm (4.9–6.3 THz) and 250–6000 μm (0.05–1.19 THz) with optical transparency reaching 76%. At the same time, in the long-wavelength infrared region from 800 to 6000 μm (0.05–0.37 THz) the absorption coefficient’ value hasn't exceeded 0.1 cm−1 for the AgCl − AgBr crystal system, also lied within 0.1–0.005 cm−1 for the AgBr − AgI, AgBr − TlI, AgBr − TlBr0.46I0.54 crystals systems.

Development and characterization of polycrystalline transparent CsI plate for X-ray radiography applications

In this paper we report a novel way of processing CsI powder into poly-crystalline transparent plate by vacuum hot pressing technique. The fabricated CsI plate is investigated for its microstructure and phase purity. Further we have measured the luminescence and scintillation characteristics of this plate. These measurements establish that the polycrystalline plate can have application in radiation detection. Further the efficacy of the transparent CsI plate is shown for industrial X-ray radiography applications. Our results show that this kind of CsI plate can be economically fabricated and can replace the use of CsI single crystals and thin films in specific applications like radiation detection and industrial radiography.

Evolution of layered yttrium hydroxide nitrate particles during controlled double-jet precipitation

Layered yttrium hydroxide nitrate particles Y2(OH)5(NO3)·xH2O (LYH) were synthesized by controlled double-jet precipitation (CDJP) in the pH range of 7–9.5. The pH value and the duration of precipitation, have a significant effect on the morphology and growth behavior of LYH particles. Spheroidal particles with a radial arrangement of straight polycrystalline plates were prepared at pH 7. The alignment and ordering of crystallites decreases at pH 8, which leads to the growth of many branching sheets that form huge spheroidal networks of LYH particles. During precipitation at pH > 8, irregularly shaped LYH agglomerates continuously form with a wide range of sizes. An assumption has been put forward about the decisive role of the two-step mechanism of nucleation/crystallization of LYH. The results of the study provide a simple way to prepare uniform spheroidal LYH particles promising for the production of functional oxide powders and ceramics.

Mechanism of Incongruent Reactions Between Zr-Cu Melts and Solid Tungsten Carbide

The incongruent reactions between Zr-Cu melts and WC solid were studied. Mo was used as a tracer to track the movement of “heavy” W atoms during the incongruent reaction. In separate experiments, dense polycrystalline plates and porous preforms of W0.9Mo0.1C were reacted with Zr2Cu and Zr14Cu51 melts at 1200 °C, 1300 °C and 1600 °C for 15 minutes. The microstructure of the reactive interfaces was studied using scanning electron microscopy, transmission electron microscopy and energy-dispersive X-ray spectroscopy. The change of microstructure and chemical composition at the reactive interface was observed as a function of temperature, Zr content in the melt and radius of the W0.9Mo0.1C solid. When the Zr-Cu melts contact the W0.9Mo0.1C solid, W, Mo and C all dissolve in the melt. The precipitation of W and W2Zr is based on Zr activity in the Zr-Cu melt after a quick formation of ZrCx. Both the dissolution rate and the amount of WC solid increase with decreasing radius of the WC particles, increasing Zr content in the Zr-Cu melts, and increasing reaction temperature. If the dissolution rate of WC is fast enough and the WC particles are in small sizes, the dissolution-precipitation is the main aspect. If a continuous ZrC layer quickly forms to separate the WC solid from Zr-Cu melts. The reaction is, therefore, controlled by the diffusion of carbon through the W and/or ZrC layers.

On the Reflection of Hydrogen and Deuterium Atoms from a Tungsten Crystal in the Surface Channeling Mode

The reflection coefficients and angular distributions of scattered particles under the bombardment of amorphous and crystalline tungsten targets by hydrogen and deuterium atoms are calculated. A reflection coefficient that is close to 100% is observed in the case of grazing angles of incidence on the crystalline targets. It is planned that tungsten in the form of polycrystalline plates will be used as the material for the ITER tokamak divertor. This phenomenon should be taken into account when calculating the energy input into the divertor.

Optical breakdown threshold of silver halide polycrystalline structures acted on by the pulsed radiation of a Ho:YAG laser

The optical breakdown thresholds are determined for 100-μm-thick polycrystalline plates made from AgBr0.99I0.01, Ag0.95Tl0.05Br0.95I0.05, and AgBr0.75Cl0.25 when they are irradiated by a Ho:YAG laser at 2.096 μm (pulse-repetition rate 10 kHz and pulse width 25 ns). The dependences of the transmittances of these samples on the mean power of the laser radiation are obtained. It is shown that the optical breakdown threshold depends on the transmittance of the material. The mean optical breakdown threshold of the samples lies in the region from 0.89±0.09 to 1.13±0.09 J/cm2.

Growing optical Ge plates with an improved high-yield method of horizontal directed crystallization

This paper aims to disseminate an improved technique of horizontal directed crystallization (HDC) which allows several polycrystalline or single-crystalline plates to grow in each growth process.

ВПЛИВ ОБРОБКИ ПОВЕРХНІ ЗА ТЕХНОЛОГІЄЮ SMAT НА МЕХАНІЧНІ ВЛАСТИВОСТІ ПОВЕРХНЕВИХ ШАРІВ МІДІ

Nanostructured materials are characterized by a specific structure compared to polycrystalline materials. Nanostructured materials are created in way of strong deformations. SMAT (surface mechanical attrition treatment) technology consists in the treatment of the surface of a material with steel balls accelerated by a generator of high-frequency oscillations (about 20 kHz). This changes the mechanical properties of the materials. The size of graines in such materials decreases in the direction from the volume of the crystal to the surface. As a result of SMAT processing, graines become nanosized near the surface of the samples. Such materials have a large number of subsurface defects formed as a result of intense plastic deformation, which determines their thermodynamic and diffusion characteristics. The purpose of this work is to develop the device of high-frequency (20 kHz) surface machining by attrition using SMAT technology and its application to the treatment of surfaces, both polished copper plates and electrodeposited in a stationary mode to copper plates with copper layers. In this work, the device is developed and the technology of high-frequency mechanical surface treatment of SMAT is described. The design features and technical characteristics of the experimental plant are presented. In the work, the surfaces of copper substrates were processed by different methods: grinding and polishing of copper polycrystalline plates, electrolytic deposition of copper surface layers on these plates, processing of prototypes by SMAT technology. The microhardness was measured in the surface layers of the linings made using different technologies and their comparative characteristics were performed. It is established that high-frequency surface treatment of plates by SMAT technology increases the microhardness of the surface of copper plates of different types, both polished and with electrolytically deposited copper. The results of the research showed that the sample, which was subjected to electrolytic deposition of copper, has a high defectiveness of the surface and reduced microhardness. After processing such a sample using SMAT technology, it is obtained a hardness higher than the reference polycrystalline copper sample.

Nanocarbon colloid produced by electro-spark discharge in ethanol for seeding the substrates in MPACVD synthesis of polycrystalline diamond films

We produced a nanocarbon colloid by electro-spark discharge as substrate seeding for microwave plasma-assisted chemical vapor deposition (MPACVD) synthesis of micro- and nano-crystalline diamond films and solid free-standing microcrystalline diamond plates. The colloid was produced by a specially designed device via a pulse electro-spark discharge in ethanol. The nanocrystalline diamond films and polycrystalline plates that were grown were examined by optical, SEM and TEMmicroscopies and Raman spectroscopy.

Ultrastructure of Bone: Hierarchical Features from Nanometer to Micrometer Scale Revealed in Focused Ion Beam Sections in the TEM.

The ultrastructure of bone has been widely debated, in part due to limitations in visualizing nanostructural features over relevant micrometer length scales. Here, we employ the high resolving power and compositional contrast of high-angle annular dark-field scanning transmission electron microscopy (HAADF STEM) to investigate new features in human bone with nanometer resolution over microscale areas. Using focused ion beam (FIB)-milled sections that span an area of 50μm2, we have shown how most of the mineral of cortical human osteonal bone occurs in the form of long, thin polycrystalline plates (mineral lamellae, MLs) which are either flat or curved to wrap closely around collagen fibrils. Close to the collagen fibril (< 20nm), the radius of curvature matches that of the fibril diameter, while at greater distances, MLs form arcs with much larger radii of curvature. In addition, stacks of closely packed planar (uncurved) MLs occur between fibrils. The curving of mineral lamellae both around and between the fibrils would contribute to the strength of bone. At a larger scale, rosette-like clusters of fibrils are noted for the first time, arranged in quasi-circular arrays that define tube-like structures in alternating osteonal lamellae. At the boundary between adjacent osteonal lamellae, the orientation of fibrils and surrounding mineral lamellae changes abruptly, resembling the "orthogonal" patterns identified by others (Reznikov et al. in Acta Biomater 10:3815-3826, 2014). These features spanning nanometer to micrometer scale have implications for our understanding of bone structure and mechanical integrity.

Measuring spectral transmission and refractive index of AgCl1−xBrx (0 ⩽ x ⩽ 1) and Ag1−xTlxBr1−xIx (0 ⩽ x ⩽ 0.05) at the wavelength of 10.6 μm

We measured the complex refractive index at the wavelength of 10.6μm with the help of Fourier transform infrared spectroscopy for polycrystalline plates of the following compositions AgCl1−xBrx (0⩽x⩽1) and Ag1−xTlxBr1−xIx, where x varied from 0 to 0.05. In order to do it we chose a segment of the spectrum, which was recorded with a high resolution (0.5cm−1) using the HgCdTe detector and which had a set of 10 identical peaks. It is shown that the real part of the refractive index rises along with increasing the substituting component fraction in the solid solution from 1.99 to 2.17 for AgCl1−xBrx and from 2.17 to 2.24 within the range of TlI mole fraction up to 0.05 for Ag1−xTlxBr1−xIx. We considered errors introduced by the spectrometer resolution and the accuracy rating of the micrometer, which was used to measure sample thickness. It is seen in the spectra, recorded for the second system with a lower resolution and using a deuterated and l-alanine doped triglycine sulfate detector, that increasing the thallium monoiodide fraction results in widening the transmission range towards bigger wavelengths. We also plan to use the obtained refractive index values for simulating mid-infrared optical fibers, the polycrystalline structure of which is close to the structure of the plates under investigation.

Microtribological modification of silicon carbide surface by laser irradiation

AbstractThis study aims to form lubricative carbon layers on the surfaces of sintered plates and thin films of silicon carbide (SiC) by local laser irradiation. This technique is suitable for use with micro-device applications on which it is difficult to add a lubricative agent. The proposed method is based on silicon elimination from SiC, which is referred to as the carbide derived carbon process. The local modification is performed on sintered polycrystalline plates and amorphous thin films using an infrared laser with/without pre-heating, and it is found that modified layers can be obtained on both specimens. Elemental, molecular structural, and frictional analyses of the layers are then conducted, demonstrating that the layer on the sintered plate primarily consists of sp2-bonded carbon with some defects and remaining silicon. The chemical bonding continuity, purity, and thickness of the layers depend on the laser irradiation conditions. On the amorphous thin film, the modified layer is composed of amorphous carbon with a depth of several nanometers. The friction coefficients are measured using a scanning probe microscope under micro-order loads. The modified layers of both the sintered plates and thin films exhibit low friction coefficients. The friction coefficient of the modified layer is approximately half that of the as-prepared or deposited SiC.

Platinum Dissolution from Carbon Supported Nanoparticles

Platinum (Pt) dissolution concerns the instability of Pt-based cathode catalysts for polymer electrolyte fuel cells (PEFCs). Studies on unsupported Pt, polycrystalline plates or electroplated films, suggest that Pt dissolution relates to Pt oxide formation and reduction. Pt dissolution from the carbon supported nanoparticles, however, is rarely discussed. In this study, we investigated Pt dissolution using commercial carbon supported nanoparticles (Pt/C). We prepared Nafion-free inks by mixing Pt/C samples with H2O and isopropyl alcohol (IPA). We evaluated the amount of Pt dissolution over potential cycling tests using inductively-coupled plasma-mass spectrometry (ICP-MS). We also scrutinized the Pt dissolution behaviors from the Pt/C in a single cycle using a channel flow double electrode (CFDE)1. The Pt/C samples we used were produced by Tanaka Kikinzoku Kogyo (TKK); the Pt particle size distributions before test were characterized by TEM. For each Pt/C sample, we mixed about 10 ~ 15 mg Pt/C with 3.8 ml H2O and 1.2 ml IPA, and sonicated the mixture in an ice bath for 60 mins. We loaded an appropriate amount of ink on a glassy carbon (GC) substrate. The Pt/C electrode was then dried under an ambient atmosphere for 120 mins. The Pt/C electrode was cycled 30 or more times between 0.05 and 1.4 V (vs. SHE) in 0.5 M H2SO4 to remove organic adsorbents and to obtain a reproducible electrochemical surface area (ECSA). The ECSA was used for normalization of Pt dissolution. First, we conducted 300 cycles of potentials cycling in 0.5 M H2SO4 in a stationary cell. The geometric surface area of the GC was ca. 0.25 cm2 and we loaded about 2 µl ink on it. Two upper potential limits (E U) of 1.0 and 1.4 V were used with a same lower potential limit (EL ) of 0.4 V. The testing solutions were analyzed by ICP-MS. Second, we tested Pt dissolution from the Pt/Cs using a CFDE in argon-deaerated 0.5 M H2SO4. The CFDE consisted of a GC working electrode (WE) and a gold (Au) collector electrode (CE). The geometric surface area of the GC was ca. 0.05 cm2 and we loaded about 0.6 µl ink on it. The CV of a 46wt% Pt/C obtained in the CFDE at 25oC shows that the Pt/C is relatively stable without Nafion. Pt dissolution from the Pt/C-WE was monitored by the CE. The CE collected 30% of dissolved Ptn+. We set the CE at 1.4 V for detecting Pt2+, and at 0.7 V for Pt4+. We also set the CE at 0.3 V for collection of both Pt species. The ICP-MS data evaluate the overall amount of Pt dissolution and CFDE data provide details of the dissolution behaviors against potential. Using both data, we discuss the mechanism of Pt dissolutions from the Pt/Cs with respect to temperature, E U, and Pt particle size. Reference 1. Z. Wang, E. Tada, and A. Nishikata, J. Electrochem. Soc., 161 (4), F380 (2014). Figure 1