High Crystalline Content Research Articles

Glacial geology of Saalian relief around Midwolda, eastern Groningen, the Netherlands

AbstractDue to canal-digging activities in 2011 and 2014, two small and one large temporary exposure, all ranging from 4 to 5 m in depth, were studied with respect to the sedimentology and structural geology, in the glacial ridge of Midwolda, Groningen, the Netherlands. The lowermost unit consists of clay of Elsterian age and is composed of glaciolacustrine and turbiditic deposits (Peelo Formation). These show synsedimentary deformations due to loading, as well as post-sedimentary Saalian glaciotectonic deformations, consisting of folding, and faulting structures. The overlying Saalian till sequence consists of two main units. The lower unit, with clear features of a subglacial deformation zone (e.g. lateral heterogeneity), has a local origin and strongly resembles the underlying Elsterian clay. Glacial tectonic and morphological observations indicate a primary NE–SW ice-flow direction. The second till layer has a sandy texture and high crystalline gravel content, while glacial-tectonic indicators point to a NW–SE ice-flow direction. The deformation of the till layers has caused a repetition and mixing of till layers, due to the last ice movement. The NW–SE ice movement is supported by the morphology as well as data from erratic gravel counts. Correlation with geological cross-sections strongly suggests regional subsurface control on ice-sheet behaviour.

Insights into the effects of modifying factors on the solvent-free synthesis of FeAPO-5 catalysts towards phenol hydroxylation

A modified solvent-free method has been developed to synthesize FeAPO-5 zeolite catalysts with hierarchical porous structure as well as high crystallinity and iron content. The effects of mechanochemical and low-temperature pretreatment, as well as the addition of hydrogen peroxide and seed crystals on the synthesis of FeAPO-5 were studied in detail. The composition and structural features of relatively pure resultant products were deeply analyzed by XRD, SEM, ICP-AES, CHN analysis, TG–DTA, UV–Vis diffuse reflectance spectroscopy and N2 physisorption. Most importantly, low-temperature pretreatment towards H2O2-containing precursor mixtures can to a great degree improve the crystallinity of FeAPO-5 molecular sieve. Significantly, compared to the conventional micron-sized microporous FeAPO-5 zeolite, the hierarchical FeAPO-5 catalysts created by this modified solvent-free method show superior performance in phenol hydroxylation, in which the one with a high content of framework iron species exhibits the best catalytic performance, giving phenol conversion of about 40% and dihydroxybenzene selectivity of up to 80% at 50 °C within 3 h reaction time.

Morphology, Mechanical Properties and Dimensional Stability of Biomass Particles/High Density Polyethylene Composites: Effect of Species and Composition.

The utilization of four types of biomass particles, including hardwood (poplar), softwood (radiata pine), crop (wheat straw) and bamboo (moso bamboo), as reinforcing fillers in preparing high density polyethylene (HDPE) based composites was studied. To improve interfacial compatibility, maleic anhydride grafted polyethylene (MAPE) was applied as the coupling agent. The effects of the biomass species on the mechanical and water absorption properties of the resulting composites were evaluated based on chemical composition analysis. A creep-recovery test was conducted in single cantilever mode using a dynamic mechanical analyzer. Results show that the four types of biomass particles had similar chemical compositions but different composition contents. Poplar particles with high cellulose content loading in the HDPE matrix exhibited higher tensile and flexure properties and creep resistance. Fracture morphology analysis indicated a weak particle-matrix interface in wheat straw based composites. Given the high crystallinity and minimum hemicellulose content, the moso bamboo reinforced composite showed high impact strength and better water resistance.

Investigations into the structure of PEO-layers for understanding of layer formation

Plasma electrolytic oxidation (PEO) is a type of high-voltage anodic oxidation process capable of producing a thick oxide layer with a wide variety of structural and chemical properties influenced by the electrolytic system. This process enables the combined adjustment of various characteristics, i.e. the morphology and chemical composition. The procedure facilitates the possibility of generating an individual structure as well as forming a crystalline surface in a single step. A highly porous surface with a high crystalline content consisting of titanium dioxide phases is ensured through the process of plasma electrolytic oxidizing pure titanium. In the present study plasma electrolytic oxidized TiO2-layers were investigated regarding their crystallinity through the layer thickness. The layers were prepared with a high applied voltage of 280 V to obtain a PEO-layer with highly crystalline anatase and rutile amounts. Raman spectroscopy and electron backscatter diffraction (EBSD) were selected to clarify the structure of the oxide layer with regard to its crystallinity and phase composition. The composition of the TiO2-phases is more or less irregularly distributed as a result of the higher energy input on the uppermost side of the layer. Scanning transmission electron microscopy (STEM) provided a deeper understanding of the structure and the effects of plasma discharges on the layer. It was observed that the plasma discharges have a strong influence on crystallite formation on top of the oxide layer and also at the boundary layer to the titanium substrate. Therefore, small crystallites of TiO2 could be detected in these regions. In addition, it was shown that amorphous TiO2 phases are formed around the characteristic pore structures, which allows the conclusion to be drawn that a rapid cooling from the gas phase had to take place in these areas.

Exploring an oxidative bleaching treatment for Chilean bamboo: a source of cellulose for biofuel generation and the nanotech industry

Quila (Chusquea quila) is a very abundant native Chilean bamboo species. This work reports on a delignification process which can be applied to quila to produce crystalline cellulose, an important resource for obtaining cellulose nanofibres or nanocrystals. Alternatively, the crystalline cellulose can then be subjected to fermentation processes, making it a useful raw material for biofuel production. The treatment studied is an oxidative treatment at low concentration (15% v/v), for short time periods (10, 20 min) and at temperatures between 100 and 140 °C, which produces alpha-cellulose fibres with high crystallinity (over 70%) and low residual lignin content (< 2%). The morphology of the cellulose fibres was analysed by scanning electron microscope, revealing a smooth surface containing many fibrils. Infrared spectroscopy was used to identify functional groups, showing that almost 99% of the lignin was removed. The crystallinity index of the cellulose fibres after the reaction was up to 79%, making it an excellent raw material for processing cellulose nanofibres required by the emerging nanotech industry. Carbohydrate analysis revealed 86% glucose and 14% xylose, which makes quila a promising candidate as a precursor for biofuel generation.

Development of InAlAsSb growth by MOVPE

The growth of InAlAsSb by metal-organic vapor phase epitaxy has been demonstrated, with a controllable antimony fraction exceeding 6%. Calculations have shown that InAlAsSb with Sb contents greater than 5–7% in the quaternary are within the miscibility gap, however this work demonstrates specific growth conditions that allow compositions well within the miscibility gap. From a study of the growth of AlAsSb and an evaluation of two aluminum precursors (TMAl versus TTBAl), growth temperature, and V/III ratio, a foundation is developed to optimize the growth of InAlAsSb. By tailoring V/III ratio, growth conditions were found to achieve high crystalline content of both indium and antimony. InAlAsSb was grown on InP with antimony fractions from 32% to 48%, for which indium fraction varied from 10% to 19%, which provides an expected direct bandgap ranging from 1.75 to 1.98eV.

Tratamento de superfície para a cimentação adesiva de cerâmicas à base de zircônia: revisão de literatura

Objetivo: analisar, por meio de uma revisão da literatura, os diferentes métodos de tratamento de superfície de peças protéticas à base de zircônia e os seus efeitos sobre a cimentação adesiva. Material e Métodos: a seleção dos artigos foi realizada por meio de uma busca na base de dados PubMed/MEDLINE. A amostra final foi composta por 31 estudos publicados entre 2011-2016. Resultados: as cerâmicas à base de zircônia (ZrO2) têm propriedades importantes, como durabilidade química, alta tenacidade à fratura, módulo de elasticidade e dureza. Apesar da dificuldade de ligação da superfície da ZrO2 aos cimentos resinosos, estes são uma boa opção para unir as restaurações indiretas aos tecidos dentários. Entretanto, o condicionamento com ácido hidrofluorídrico e a silanização não melhoram a força de união entre o cimento resinoso convencional e cerâmica de alto conteúdo cristalino. Por esta razão, é necessário um modo de tratamento de superfície diferente para proporcionar uma força de ligação adequada. Conclusão: os estudos disponíveis sugerem que o jateamento com partículas de óxido de alumínio e a silicatização proporcionam rugosidade superficial e uma adequada resistência adesiva, no entanto, induzem à transformação de fase tetragonal em monoclínica. Por outro lado, a infiltração seletiva por vidro demonstra não gerar danos à superfície da ZrO2, porém, há a necessidade de mais pesquisas sobre esse recente método.

Electrochemical rutile and anatase formation on PEO surfaces

A highly porous surface with a high crystalline content and resultant photocatalytic activity is ensured through the process of plasma electrolytic oxidation on pure titanium. In the present study the morphology, crystallinity and photocatalytic activity of plasma electrolytic oxidized TiO2-surfaces were investigated. The surfaces were prepared in acidic and alkaline electrolytes over an applied voltage range between 50V and 300V to optimize the crystalline and photocatalytic properties. Scanning electron microscopy (SEM) and X-ray powder diffraction (XRD) were selected to determine the morphologies which differ according to the type of electrolyte as well as the crystal structures of anatase and rutile on the surface material, which increase with the applied voltage. The oxide surfaces did not show morphological differences compared to typical PEO surfaces with the exception of oxide films obtained in H2SO4-solution which also exhibited an astounding amount of rutile even with low applied voltages. The increased parts of anatase and rutile on the surfaces resulted in photocatalytic activity, which was investigated under UV-light using methylene blue, while the PEO surfaces showed degradation activity. There is an indication that a high proportion of anatase and small amounts of rutile in the PEO layers positively influence photocatalytic activity.

Deformation-induced crystalline structure evolutions of isotactic poly-1-butene

The deformation-induced crystalline structure evolutions of isotactic poly-1-butene (iP-1-B) during uniaxial stretching at different temperatures (45 and 75 °C) were investigated with in situ wide-angle X-ray scattering (WAXS) technology. The form I of iP-1-B was employed in this study. The obtained data on structure evolutions revealed that orientations would occur when the applied stress reached a critical value, while the orientation mechanisms are different at the two investigated temperatures. The crystallinity at 75 °C declines fast during deformation, and the orientation is caused by the melting disparity between the crystals parallel and perpendicular to the stretching direction. The high crystalline content during stretching at 45 °C maintains throughout the tensile process and the rotation of crystalline blocks results in the orientation. A brief schematic diagram was given to clarify the routes of orientation at the two temperatures.

Layer Protecting the Surface of Zirconium Used in Nuclear Reactors.

Zirconium alloys have very useful properties for nuclear facilities applications having low absorption cross-section of thermal electrons, high ductility, hardness and corrosion resistance. However, there is also a significant disadvantage: it reacts with water steam and during this (oxidative) reaction it releases hydrogen gas, which partly diffuses into the alloy forming zirconium hydrides. A new strategy for surface protection of zirconium alloys against undesirable oxidation in nuclear reactors by polycrystalline diamond film has been patented- Czech patent 305059: Layer protecting the surface of zirconium alloys used in nuclear reactors and PCT patent: Layer for protecting surface of zirconium alloys (Patent Number: WO2015039636-A1). The zirconium alloy surface was covered by polycrystalline diamond layer grown in plasma enhanced chemical vapor deposition apparatus with linear antenna delivery system. Substantial progress in the description and understanding of the polycrystalline diamond/ zirconium alloys interface and material properties under standard and nuclear reactors conditions (irradiation, hot steam oxidation experiments and heating-quenching cycles) was made. In addition, process technology for the deposition of protective polycrystalline diamond films onto the surface of zirconium alloys was optimized. Zircaloy2 nuclear fuel pins were covered by 300 nm thick protective polycrystalline diamond layer (PCD) using plasma enhanced chemical vapor deposition apparatus with linear antenna delivery system. The polycrystalline diamond layer protects the zirconium alloy surface against undesirable oxidation and consolidates its chemical stability while preserving its functionality. PCD covered Zircaloy2 and standard Zircaloy2 pins were for 30 min. oxidized in 1100°C hot steam. Under these conditions α phase of zirconium changes to β phase (more opened for oxygen/hydrogen diffusion). PCD anticorrosion protection of Zircaloy nuclear fuel assemblies can significantly prolong lifetime of Zirconium alloy in nuclear reactors even above Zirconium phase transition temperatures. Even after ion beam irradiation (10 dpa, 3 MeV Fe(2+)) the diamond film still shows satisfactory structural integrity with both sp(3) and sp(2) carbon phases. Zircaloy2 under the carbon-based protective layer after hot steam oxidation test differed from the original Zircaloy2 material composition only very slightly, proving that the diamond coating increases the material resistance to high temperature oxidation. Zirconium alloys nuclear fuel pins' surfaces were covered by compact and homogeneous polycrystalline diamond layers consisting of sp(3) and sp(2) carbon phases with a high crystalline diamond content and low roughness. Diamond withstands very high temperatures, has excellent thermal conductivity and low chemical reactivity, it does not degrade over time and (important for the nuclear fuel cladding) being pure carbon, it has perfect neutron cross-section properties. Moreover, polycrystalline diamond layers consisting of crystalline (sp(3)) and amorphous (sp(2)) carbon phases could have suitable thermal expansion. Zirconium alloys coated with polycrystalline diamond film are protected against undesirable changes and processes. Further, the polycrystalline diamond layer prevents the reaction between the alloy surface and water vapor. During such reaction, water molecules dissociate and initiate formation of zirconium dioxide and hydrogen, accompanied by the release of large amount of heat. Thus the protective layer prevents the formation of hydrogen and the release of reaction heat. Few relevant patents to the topic have been reviewed and cited.

Effect of F-S Mineralizer on the Calcination of Recycled Cement Clinker Produced from Waste Concrete

The recycled cement production, utilizing all components of the waste concrete without separation treatment as raw materials, provides an effective method for the high value-added resource recovery of waste concrete. However, as fine aggregate (sand) is the main siliceous component in the recycled cement raw materials prepared from waste concrete, its excessive high-crystalline silica content negatively impacts the burnability of raw meal and the property of clinker. By comparing and analyzing the results of burnability test, XRD patterns of clinker and compression strengths of cement paste, this paper attempts to explore the effect of F-S mineralizer on the calcination of recycled cement clinker produced from waste concrete. It could be concluded that F-S mineralizer has a significant improvement on the burnability of recycled cement raw meal, and the f-CaO content decreases with the mineralizer dosage rising. Moreover, in the case of calcination temperature at 1350°C, F-S mineralizer contributes to the enhancement of compression strength of recycled cement paste. Early high-strength minerals ( and C11A7⋅CaF2) are prime motivator to early strength increment, while long-term strength benefits from mineralizer’s improving on hydration activity of silicate mineral in clinker.

The global variability of diatomaceous earth toxicity: a physicochemical and in vitro investigation.

BackgroundDiatomaceous earth (DE) is mined globally and is potentially of occupational respiratory health concern due to the high crystalline silica content in processed material. DE toxicity, in terms of variability related to global source and processing technique, is poorly understood. This study addresses this variability using physicochemical characterisation and in vitro toxicology assays.MethodsNineteen DE samples sourced from around the world, comprising unprocessed, calcined and flux-calcined DE, were analysed for chemical and mineral composition, particle size and morphology, and surface area. The potential toxicity of DE was assessed by its haemolytic capacity, and its ability to induce cytotoxicity or cytokine release by J774 macrophages.ResultsThe potential toxicity of DE varied with source and processing technique, ranging from non-reactive to as cytotoxic and haemolytic as DQ12. Crystalline silica-rich, flux-calcined samples were all unreactive, regardless of source. The potential toxicity of unprocessed and calcined samples was variable, and did not correlate with crystalline silica content. Calcium-rich phases, iron content, amorphous material, particle size and morphology all appeared to play a role in sample reactivity. An increased surface area was linked to an increased reactivity in vitro for some sample types.ConclusionsOverall, no single property of DE could be linked to its potential toxicity, but crystalline silica content was not a dominant factor. Occlusion of the potentially toxic crystalline silica surface by an amorphous matrix or other minerals and impurities in the crystal structure are suggested to pacify toxicity in these samples. In vivo verification is required, but these data suggest that crystalline silica content alone is not a sufficient indicator of the potential DE hazard.Electronic supplementary materialThe online version of this article (doi:10.1186/s12995-015-0064-7) contains supplementary material, which is available to authorized users.

Adhesion to Dental Ceramics

All-ceramic restorations are attractive because of their long lasting esthetics and the ability to with- stand the oral conditions. However, bonding to ceramics has challenged the dental community for the last few decades. The clinical success of a ceramic restoration is strongly dependent on the quality and durability of the bond between the resin cement and the restoration. This study presents the bonding mechanisms and the me- chanical tests to evaluate the adhesive interfaces of resin-bonded ceramic restorations, mainly the zirconia- based restorations, which are the most popular. An adequate bond involves ceramic surface changes for mechanical retention, which can be achieved using primers, such as acids and airborne particle abrasion. Selective etching of high crystalline content ceramics mostly occurs within grain boundaries that offer little micromechanical retention and an insufficient bond to resin. The most popular surface treatment to improve adhesion to high crystalline content ceramics involves the treatment of surfaces with airborne particle abrasion and chemical bonding. Yet, there are reports on new methods to enhance the resin bond to zirconia that need further investigation. This study provides scientific evi- dences to guide the clinical procedures on bonding ceramic restorations.

Contemporary Ceramics and Cements

Contemporary Ceramics and Cements

Enhanced photocatalytic activity of TiO2/carbon@TiO2 core–shell nanocomposite prepared by two-step hydrothermal method

Abstract A unique TiO2/carbon@TiO2 core–shell nanocomposite was fabricated by a two-step hydrothermal method. High-resolution transmission electron microscopy images show the size of the nanocomposites is about 50–100 nm, which are composed of well-defined crystallized titania on the shell with the TiO2/carbon composite as the core. The existence of the amorphous carbon in the core can be proved by Raman spectra and thermogravimetric analysis. X-ray diffraction pattern and Raman spectra show that the crystalline of TiO2 is improved after the second hydrothermal treatment and the TiO2 are the pure anatase phase. Measurements of the photocatalytic degradation of rhodamine B show that the photocatalytic activity of TiO2/carbon@TiO2 core–shell nanocomposite is higher than that of the initial TiO2/C core and pure TiO2 because TiO2 on the shell has high crystallinity and high content of surface oxygen vacancies (SOVs) after the second hydrothermal treatment. Moreover, the synergistic catalytic effect of the carbon in the core can also enhance the photocatalytic activity of the nanocomposite, such as retarding the recombination of photo-generated electron–hole pairs and absorbing more light.

Artificial Stone Silicosis: Disease Resurgence Among Artificial Stone Workers

Silicosis is a progressive, fibrotic, occupational lung disease resulting from inhalation of respirable crystalline silica. This disease is preventable through appropriate workplace practices. We systematically assessed an outbreak of silicosis among patients referred to our center for lung transplant.This retrospective cohort analysis included all patients with a diagnosis of silicosis who were referred for evaluation to the National Lung Transplantation Program in Israel from January 1997 through December 2010. We also compared the incidence of lung transplantation (LTX) due to silicosis in Israel with that of the International Society for Heart and Lung Transplantation (ISHLT) registry.During the 14-year study period, 25 patients with silicosis were referred for evaluation, including 10 patients who went on to undergo LTX. All patients were exposed by dry cutting a relatively new, artificial, decorative stone product with high crystalline silica content used primarily for kitchen countertops and bathroom fixtures. The patients had moderate-to-severe restrictive lung disease. Two patients developed progressive massive fibrosis; none manifested acute silicosis (silicoproteinosis). Three patients died during follow-up, without LTX. Based on the ISHLT registry incidence, 0.68 silicosis cases would have been expected instead of the 10 observed (incidence ratio, 14.6; 95% CI, 7.02-26.8).This silicosis outbreak is important because of the worldwide use of this and similar high-silica-content, artificial stone products. Further cases are likely to occur unless effective preventive measures are undertaken and existing safety practices are enforced.

Effect of the microstructure on the lifetime of dental ceramics

Objectives To evaluate the effect of the microstructure on the Weibull and slow crack growth (SCG) parameters and on the lifetime of three ceramics used as framework materials for fixed partial dentures (FPDs) (YZ – Vita In-Ceram YZ; IZ – Vita In-Ceram Zirconia; AL – Vita In-Ceram AL) and of two veneering porcelains (VM7 and VM9). Methods Bar-shaped specimens were fabricated according to the manufacturer's instructions. Specimens were tested in three-point flexure in 37 °C artificial saliva. Weibull analysis ( n = 30) and a constant stress-rate test ( n = 10) were used to determine the Weibull modulus ( m) and SCG coefficient ( n), respectively. Microstructural and fractographic analyzes were performed using SEM. ANOVA and Tukey's test ( α = 0.05) were used to statistically analyze data obtained with both microstructural and fractographic analyzes. Results YZ and AL presented high crystalline content and low porosity (0.1–0.2%). YZ had the highest characteristic strength ( σ 0) value (911 MPa) followed by AL (488 MPa) and IZ (423 MPa). Lower σ 0 values were observed for the porcelains (68–75 MPa). Except for IZ and VM7, m values were similar among the ceramic materials. Higher n values were found for YZ (76) and AL (72), followed by IZ (54) and the veneering materials (36–44). Lifetime predictions showed that YZ was the material with the best mechanical performance. The size of the critical flaw was similar among the framework materials (34–48 μm) and among the porcelains (75–86 μm). Significance The microstructure influenced the mechanical and SCG behavior of the studied materials and, consequently, the lifetime predictions.

Insights on Ceramics as Dental Materials. Part II: Chemical Surface Treatments

The purpose of surface treatment (conditioning) methods on dental ceramics is to improve the retention and bonding between the enamel or the dentin and ceramic veneer, with the help of resin composite luting cements. These types of surface treatments include chemically altering the surface of ceramics with some specific acidic etchants followed by applying a silane coupling agent (silane). The silane currently used in dentistry is 3-methacryloxypropyltrimethoxysilane, a hybrid organic–inorganic trialkoxy ester monomer, which is diluted in an acidified water-ethanol solvent system. Such silane primers are said to be pre-hydrolyzed. Some oxide ceramics with high crystalline content, such as alumina and zirconia, cannot be easily etched with acid etchants. They should be silica-coated and silanized prior to bonding. A silane coupling agent should be applied after silica-coating to the ceramic surface to achieve chemical bonding and the optimal durable bond strength.

Bench-scale synthesis of zeolite A from subbituminous coal ashes with high crystalline silica content

In this present work, fly ash and bottom ash with high crystalline silica content were obtained from the coal-fired boilers within the paper industries in Thailand. These coal ashes were used as the basic raw materials for synthetic zeolite production. The crystal type and crystallinity, specific surface area and pore size, and textural properties of zeolite products were characterized by using X-ray diffraction spectroscopy (XRD), N 2 sorption analysis, and Scanning Electron Microscopy (SEM), respectively. It was found that sodalite octahydrate was selectively formed via the direct conventional (one-step) synthesis, whereas through a two-step, sodium silicate preparation and consecutive zeolite A synthesis process, 94 and 72 wt.% zeolite A products could be produced from the fly ash and bottom ash, respectively. The cation-exchange capacity (CEC) of fly ash and bottom ash-derived zeolite A products were closely similar to that of the commercial grade zeolite A.

Surface roughness of glazed feldspar, alumina, and zirconia-based ceramics

The aim of this study was to compare the mean surface roughness (Ra) of feldspar-, alumina-, and zirconia-based ceramics, testing the hypothesis that the feldspathic ceramics have lower average surface roughness (Ra) than the ceramics used for infrastructure. Eight disk specimens (5mm in diameter; 2mm in thickness) of each ceramic material were fabricated according to the manufacturer’s specifi cations: V7-feldspathic veneer ceramic (Vita VM7); VA-feldspathic veneer ceramic (Vitadur-α); IA-slip casted, glass-infi ltrated alumina-based ceramic (Vita In-Ceram Alumina); IZS-slip casted, glass-infi ltrated zirconia-reinforced alumina-based ceramic (Vita In-Ceram Zirconia); IZB-dry-pressed block ofglass-infi ltrated zirconia-reinforced alumina-based ceramic (Vita In-Ceram Zirconia 2000 for Cerec InLab). All materials were glazed as recommended by the manufacturer. Four Ra readings (Mitutoyo SJ 400) per specimen were performed, averaging the value per specimen (n=8). Ra values were statistically analyzed using one-way ANOVA and Tukey test (α=0.05). V7 showed the lowest mean Ra value (0.43±0.07 μm) compared to the other ceramics. There were no statistical differences between the mean Ra values of VA (0.94±0.2 μm), IA (0.7±0.13 μm), IZS (0.98±0.3 μm) and IZB (0.75±0.4 μm). The testing hypothesis was partially accepted. V7 showed a smoother ceramic surface than the VA. There were no statistically differences between the mean Ra value of the high crystalline content ceramics (IA, IZS, IZB).