Natural Tiling Research Articles

A Sodium Germanosilicide with Unusual Network Topology.

The germanosilicide Na4-xGeySi16-y (0.4 ≤ x ≤ 1.1, 4.7 ≤ y ≤ 9.3) was synthesized under high-pressure, high-temperature conditions. The novel guest-host compound comprises a unique tetrel framework with dual channels housing sodium and smaller, empty (Si,Ge)9 units. The arrangement represents a new structure type with an overall structural topology that is closely related to a hypothetical carbon allotrope. Topological analysis of the structure revealed that the guest environment space cannot be tiled with singular polyhedra as in cage compounds (e.g., clathrates). The analysis of natural tilings provides a convenient method to unambiguously compare related tetrel-rich structures and can help elucidate new possible structural arrangements of intermetallic compounds.

Growing bio-tiles using microbially induced calcium carbonate precipitation

Using the biomimetic process known as microbially induced calcium carbonate precipitation (MICP), the growth of bio-tiles was investigated as an alternative to conventionally fired ceramic tiles which require operating temperatures above 1000 °C, therefore adding to global carbon emissions. The ureolytic activity of Sporosarcina pasteurii was controlled by centrifuging and dilution with fresh yeast extract media. The bio-tiles were grown using a novel submersion method in which custom moulds were placed in exact positions within the bio-reactor and each was mixed individually from beneath. Five parameters were optimised to achieve bio-tiles (dimensions of 100 × 100 × 10 mm) of breaking strength comparable to conventional tiles of equivalent thickness. By optimising ureolytic activity (4.0 mmol/L·min), the cementation solution concentration (0.3 M), the particle size distribution (D10 = 312 μm; D50 = 469 μm), the volume of cementation solution, as well as the addition of supplemental magnesium (0.3 M), bio-tiles with a breaking strength 637 N ± 60 N and a modulus of rupture of 13.0 N/mm2 ± 2.3 N were produced. These parameters exceed the conventional standards of breaking strength and modulus of rupture of 600 N and 8 N/mm2, respectively, the standards set for tiles with a water absorption above 10 %. This is also the first time that an optimum CaCO3 precipitation rate constant has been identified (0.11–0.18 day−1) for producing bio-tiles that meet the strength properties of conventional extruded ceramic tiles. The tile manufacturing technique described in this study is easy to operate and scale since multiple bio-tiles can be produced in larger cementation tanks. This natural tile making process also benefits the environment by operating at room temperature.

Quantitative Structural Description of Zeolites by Machine Learning Analysis of Infrared Spectra

Application of machine learning (ML) algorithms to spectroscopic data has a great potential for obtaining hidden correlations between structural information and spectral features. Here, we apply ML algorithms to theoretically simulated infrared (IR) spectra to establish the structure-spectrum correlations in zeolites. Two hundred thirty different types of zeolite frameworks were considered in the study whose theoretical IR spectra were used as the training ML set. A classification problem was solved to predict the presence or absence of possible tilings and secondary building units (SBUs). Several natural tilings and SBUs were also predicted with an accuracy above 89%. The set of continuous descriptors was also suggested, and the regression problem was also solved using the ExtraTrees algorithm. For the latter problem, additional IR spectra were computed for the structures with artificially modified cell parameters, expanding the database to 470 different spectra of zeolites. The resulting prediction quality above or close to 90% was obtained for the average Si-O distances, Si-O-Si angles, and volume of TO4 tetrahedra. The obtained results provide new possibilities for utilization of infrared spectra as a quantitative tool for characterization of zeolites.

Boron Substructures in Inorganic Borides: Network Topology and Free Space

We have analyzed polymeric boron substructures in all 1154 robust inorganic borides from the Inorganic Crystal Structure Database using topological and geometrical models as implemented in the ToposPro program package. We have classified all boron substructures into 63 topological types of atomic networks depending on the method of connection and discriminated them by periodicity into molecular, chain, layer, or framework motifs. We have revealed topological relations between boron motifs of different topologies and periodicities and found the boron substructures that can serve as templates for assembling motifs of a more complicated topology and/or a higher periodicity. We have applied the natural tiling approach to find all cages in a particular boron substructure and estimated the size of these cages with Voronoi polyhedra. The sizes of all metal atoms, which occur in the inorganic borides, have also been calculated in the same way. As a result, we have explained the composition of some borides and showed that the combined geometrical–topological approach helps one to estimate the feasibility of possible new boride structures and to refine the conditions for the synthesis or to prepare initial structural data for the subsequent predictive modeling.

Three-periodic nets, tilings and surfaces. A short review and new results.

A brief introductory review is provided of the theory of tilings of 3-periodic nets and related periodic surfaces. Tilings have a transitivity [p q r s] indicating the vertex, edge, face and tile transitivity. Proper, natural and minimal-transitivity tilings of nets are described. Essential rings are used for finding the minimal-transitivity tiling for a given net. Tiling theory is used to find all edge- and face-transitive tilings (q = r = 1) and to find seven, one, one and 12 examples of tilings with transitivity [1 1 1 1], [1 1 1 2], [2 1 1 1] and [2 1 1 2], respectively. These are all minimal-transitivity tilings. This work identifies the 3-periodic surfaces defined by the nets of the tiling and its dual and indicates how 3-periodic nets arise from tilings of those surfaces.

Generating triply periodic surfaces from crystal structures: the tiling approach and its application to zeolites.

Physical properties of objects depend on topological features of the corresponding triply periodic surfaces; thus topological exploration and classification of the surfaces has practical relevance. A general method is developed for generating triply periodic surfaces from triply periodic crystal structures. A triply periodic surface is derived from the natural tiling of a crystal network by an appropriate removal of some tile faces and subsequent smoothing of the resulting facet surface. The labyrinth nets of a generated triply periodic surface are built from the natural tiling, and in turn the topological parameters of the labyrinth nets are used to determine if the surface is isomorphic to a minimal surface. This method has been applied to all known 253 zeolite frameworks and 98 triply periodic surfaces were obtained, which belong to 55 topological types. Twelve surfaces were found to be isomorphic to already known triply periodic minimal surfaces (TPMSs), while four surfaces can be treated as isomorphic to new TPMSs. A procedure has also been developed for transferring the generated surfaces to a 3D-printer-readable format.

High-temperature behavior and structural studies on Ca14Al10Zn6O35

Abstract Single-crystals of Ca14Al10Zn6O35 suitable for structural investigations were grown from slow cooling of a melt with the same chemical composition in the range between 1300 and 1000 °C. Diffraction experiments performed at ambient temperature yielded the following crystallographic data: space group F23, a = 14.8468 (6) Å, V = 3272.6 (2) Å3, Z = 4. Structure determination and subsequent least‐squares refinements resulted in a residual of R(|F|) = 1.49% for 753 independent observed reflections and 55 parameters. The chiral structure is based on a tetrahedral framework of corner sharing (Zn,Al)O4-tetrahedra. Zn–Al-distributions among the four crystallographically independent T-sites have been studied. A detailed topological analysis based on natural tiles is presented. Actually, the net can be constructed from a total of four different cages (tiles). The largest cavities (face symbol: [316. 616]) have volumes of about 680 Å3 and host [AlO6][Ca14O36] heteropolyhedral clusters consisting of a central [AlO6] – octahedron surrounded by [CaO6]- and [CaO7]-groups. The calcium cations provide linkage to the tetrahedral framework, in other words, the [AlO6]-unit in the barycenter of the cluster is not directly connected to the framework. Furthermore, thermal expansion has been studied in the interval between 25 and 790 °C using in-situ high‐temperature single‐crystal diffraction. No indications for a structural phase transition were observed. From the evolution of the lattice parameters the thermal expansion tensor has been obtained. The response of the structure to variable temperature has been discussed.

Agricultural Waste Materials Applications in Building Industry – An Overview

Agricultural wastes have become a growing concern in recent years as the world's population has grown. Agricultural solid wastes are irresponsibly dumped or burned in public areas in several countries worldwide, resulting in air pollution, soil contamination, and smoke. The residue could end up in a water supply, polluting the water and aquatic ecology. Agricultural waste is crushed and turned into fine and coarse aggregates, or it is burned into ash, which is used in the making of concrete. Agricultural solid waste is a lightweight aggregate used in the production of masonry blocks [1]. Green concrete's thermal insulation, sound absorption, water stability, fire resistance, and mechanical properties will all be improved as a result [2]. The present paper explores the various structural components prepared by using agricultural waste materials, such as bio-bricks, natural fiber components, lightweight concrete, green concrete, concrete roofing, and tile components.

The role of local heteropolyhedral substitutions in the stoichiometry, topological characteristics and ion-migration paths in the eudialyte-related structures: a quantitative analysis.

Topological analysis of the heteropolyhedral MT framework (where M and T are octahedral and tetrahedral cations, respectively) in the eudialyte-type structure and its derivatives was performed based on a natural tiling analysis of the 3D cation. To analyze the migration paths of sodium cations in these structures, the Voronoi method was used. The parental eudialyte-type MT framework is formed by isolated ZO6 octahedra, six-membered [M(1)6O24] rings of edge-sharing M(1)O6 octahedra, and two kinds of rings of tetrahedra, [Si3O9] and [Si9O27]. Different occupancies of M(2), M(3) and M(4) sites with variable coordination numbers by the additional Q, T* and M* cations, respectively, result in 12 different types of the MT framework. Based on the results of natural tilings calculations as well as theoretical analysis of migration paths, it is found that Na+ ions can migrate through six- and seven-membered rings, while all other rings are too small for the migration. In eight types of MT frameworks, Na+-ion migration and diffusion is possible at ambient temperature and pressure, while in four other types cages are connected by narrow windows and, as a result, the Na+ diffusion in them is complicated at ambient conditions because of the window diameter, but may be possible either at higher temperatures or under mild geological conditions for long periods of time.

Soil-development differentiation across a glacial–interglacial cycle, Saalian upland, E Poland

Three soil profiles at the Koczery site (E Poland), studied through soil and sediment evaluation, reveal a polygenetic development of soils in areas unglaciated during the Weichselian glaciation (MIS 2) period. Pedogenesis had developed on glacial till (till) in period from the Saalian glaciation (MIS 6) to the Holocene (MIS 1). Wide-spectrum analyses demonstrate that the profiles represent a Planosol. Four stages (I–IV) of soil formation were distinguished in the study area. Stage I, comprising of a nutrient- and element-rich material, correlates to the accumulation of Saalian glacial till (MIS 6). Stage II, that took place during the Eemian Interglacial (MIS 5e), corresponds to the initial development of Cambisol as a result of carbonate leaching process. This was followed by the development of a Luvisol through the processes of illuviation of clay minerals and iron components. Stage III bears evidence of intensive frost weathering processes along with a development of sand-wedge cast that occurred under permafrost conditions of Weichselian glaciation (MIS 2). Further, the formation of an aeolian pavement along with erosion and removal of upper portions of the Eemian soil took place. An accumulation of coeval-age coversand led to a restart of the pedological clock, which resulted in the development of cryogenically-altered soils. Stage IV ushered the Holocene (MIS 1) delivering a progressive development of pedogenesis together with plant-succession modifications under temperate-climate conditions. Brunic or luvic horizons are formed within the coversand deposits. Pseudogleyic conditions developed along the lithological discontinuities. Of note, sand-wedge casts (SWCs) occupy specific locations in the profiles that provide the vertical migration of water, base components and iron. Reducing conditions that occurred along the bottom of ice-wedge casts favour the formation of gleyic horizon. SWCs that have been ultimately modified into ice-wedge and acted as sand-wedge-affiliated geochemical corridors (SWGC) for shallow groundwater forming natural tile drains.

Perceiving zeolite self-assembly within the natural tiling model

Perceiving zeolite self-assembly within the natural tiling model

Polytypism of Compounds with the General Formula Cs{Al2[TP6O20]} (T = B, Al): OD (Order-Disorder) Description, Topological Features, and DFT-Calculations

The crystal structures of compounds with the general formula Cs{[6]Al2[[4]TP6O20]} (where T = Al, B) display order-disorder (OD) character and can be described using the same OD groupoid family. Their structures are built up by two kinds of nonpolar layers, with the layer symmetries Pc(n)2 (L2n+1-type) and Pc(a)m (L2n-type) (category IV). Layers of both types (L2n and L2n+1) alternate along the b direction and have common translation vectors a and c (a ~ 10.0 Å, c ~ 12.0 Å). All ordered polytypes as well as disordered structures can be obtained using the following partial symmetry operators that may be active in the L2n type layer: the 21 screw axis parallel to c [– – 21] or inversion centers and the 21 screw axis parallel to a [21 – –]. Different sequences of operators active in the L2n type layer ([– – 21] screw axes or inversion centers and [21 – –] screw axes) define the formation of multilayered structures with the increased b parameter, which are considered as non-MDO polytypes. The microporous heteropolyhedral MT-frameworks are suitable for the migration of small cations such as Li+, Na+ Ag+. Compounds with the general formula Rb{[6]M3+[[4]T3+P6O20]} (M = Al, Ga; T = Al, Ga) are based on heteropolyhedral MT-frameworks with the same stoichiometry as in Cs{[6]Al2[[4]TP6O20]} (where T = Al, B). It was found that all the frameworks have common natural tilings, which indicate the close relationships of the two families of compounds. The conclusions are supported by the DFT calculation data.

Topological Features of the Alluaudite-Type Framework and Its Derivatives: Synthesis and Crystal Structure of NaMnNi2(H2/3PO4)3

A new sodium manganese-nickel phosphate of alluaudite supergroup with the general formula NaMnNi2(H2/3PO4)3 was synthesized by a hydrothermal method. The synthesis was carried out in the temperature range from 540 to 660 K and at the general pressure of 80 atm from the oxides mixture in the molar ratio MnCl2: 2NiCl2: 2Na3PO4: H3BO3: 10H2O. The crystal structure was studied by a single-crystal X-ray diffraction analysis: space group C2/c (No. 15), a = 16.8913(4), b = 5.6406(1), c = 8.3591(3) Å, β = 93.919(3), V = 794.57(4) Å3. The compound belongs to the alluaudite structure type based upon a mixed hetero-polyhedral framework formed by MX6-octahedra and TX4-tetrahedra. The characteristic feature of the title compound is the absence of cations or H2O molecules in channel II, while the negative charge of the framework is balanced by the partial protonation of PO4 tetrahedra. The presence of the transition metals at the A-type sites results in the changes of stoichiometry and the local topological features. Topological analysis of the hetero-polyhedral alluaudite-type frameworks and its derivatives (johillerite-, KCd4(VO4)3-, and keyite-type) and quantitative characterization of their differences was performed by means of natural tilings.

Preferensi Penggunaan Material pada Atap Rumah Tinggal

Roof material preferences for housing can be influenced from the location of the respondents, local climate, culture, knowledge and comfortable condition of the occupants. The aim of this research is to get the reasons behind the selection of roof material for housing. Quantitative method is used in this research by collecting data of online questionnaire. This online questionnaire is distributed using convenient sampling method (snowball-non-random-sampling). It was found the tendency of respondents who choose clay tile because of the comfort and affordability of the price. The tendency of respondents who choose ceramic tile and natural wood tile because of their beauty and sustaniability materials. Concrete is selected by respondents because of their durability and strength. Respondents who have tendency in Zinc, asbestos are selected because zinc and asbestos are easy to apply and commonly materials in their areas. Asphalt, metal, and PVC / galvalum / fiber are chosen by respondents for being lightweight materials.

Dense as diamond: Pn-C10, a superhard sp3 carbon allotrope

We introduce a carbon allotrope with rhombic symmetry and a high crystal density reached 3.56 g/cm3, named Pn-C10, which was found using an unbiased particle-swarm structural-searching technique. This fully sp3-bonded carbon phase is dynamically and mechanically stable in its ground state. Results from our calculations reveal the excellent mechanical nature of Pn-C10 with a claimed shear modulus and Vickers hardness of 484 GPa and 88.45 GPa, respectively, which also suggested its slight anisotropy in elasticity. The predicted electronic band structure indicates that Pn-C10 is an indirect-bandgap material with a bandgap of 5.05 eV. Natural tiling analysis and simulations of x-ray diffraction and Raman spectra were performed to provide insights for further studies into Pn-C10 and other carbon phases.

Aplikasi Desain Faktorial 23 pada Kadar CO2 Proses Purifikasi Bio-gas dengan Adsorben Genteng - Zeolite

The CO2 content in biogas is an impurity, so it needs to be reduced. One way to reduce the levels of CO2 in biogas is by purification with tile-zeolite adsorbents. The purpose of this study was to determine the use of tile - zeolite as an adsorbent in the purification process to reduce CO2 levels using a 23 factorial design. The use of tile powder adsorbents (25% and 75%) - Zeolite (75% and 25%), biogas flow rates of 1 and 6 liters/minute, which were investigated at intervals of 5 and 20 minutes, to collect CO2 content data. Gas Chromatography-Mass Spectrometry (GCMS) is used to test the adsorption gas content. The results are shown by the Pareto curve resulting from biogas purification of CO2 levels, each of which has a magnitude of response to CO2 levels. Increased levels of tile-zeolite as an adsorbent and the rate of biogas flow in the purification process had an effect of reducing CO2 levels by 44.214%. Conversely, an increase in tile-zeolite levels as an adsorbent increases CO2 levels in the biogas purification process. Natural tile is a porous material that can adsorb and has ions that can be exchanged with ions from the outside.

Feasibility of using cigarette butts waste in eco-friendly ceramic roofing tile

Cigarette butt is a hazardous solid waste produced in large amounts worldwide, and its improper disposal has been becoming a critical and urgent issue. This work investigates the incorporation of cigarette butt waste as an alternative raw material into an industrial roofing tile body, in replacement to natural roofing tile body by up to 5 wt.%. Roofing tile formulations containing cigarette butt waste were pressed and sintered at 1100 °C. The technical properties of the ceramic roofing tile pieces, including linear shrinkage, apparent density, weight loss, water absorption, and flexural strength, were investigated. The microstructural evolution was accompanied by scanning electron microscopy. The test results showed that cigarette butt waste could be used in eco-friendly ceramic roofing tile with good technical properties, in the range up to 5 wt.%, as a partial replacement for traditional roofing tile body, thus giving rise to a new feasible alternative for the sustainable application of cigarette butt waste.

On the complexity of fire dinamics at the wildland-urban interface

Complexity is the main feature of many fire-prone environments, in which the fire regime is driven by climate and socio-economic development on short and long timescales. In this study, the interaction between social and forest environments is modelled for the first time by assimilating socio-economic assets to a new flammable species with its own dynamics. This is a completely new approach that offers a new perspective to interpret shifts in fire regimes. The ten-years fire regime trend observed in Italy between 1970 and 2018, according to the model results, may be attributed to a progressive change of land use and inhabited development. The introduction of a new species adds complexity to fire dynamics and modifies the self-regulating Mediterranean forest fire regime. The results evidence that the evolution of a mosaic of natural and man-managed tiles of land may erase the “natural” chaotic fire regime, exacerbate fire frequency and increase fire risk in inhabited areas.

Flexural and Abrasion Behaviour of Flooring Tile with Roselle Fiber

In the world-wide research is being conducted concerning the use of fibers. This research aims to analyze the strength and behavior of natural fiber tiles relative to the conventional tiles. The researchers are exploring new materials that expand choices of flooring tiles. In this researcher produces tiles using Roselle fibers. India is the country having largest producer of roselle fiber. In this study Roselle fiber is used in two techniques, one in the form of mesh and another is mixing it with mortar. For both techniques the percentage of natural fiber was different. Because of increasing environmental problems, scientists and researchers are using natural fiber instead of synthetic fiber as the main component in composites. Cement mortar has very low tensile strength, limited ductility and little resistance to cracking. This study aims to compare flexural strength and abrasion of tiles by using natural fiber tile and conventional tile.

Perceiving Zeolite Self-Assembly: A Combined Top-Down and Bottom-Up Approach within the Tiling Model

We present an extended tiling model of the assembly of the zeolite frameworks, where the building units can be natural tiles (minimal cages of the framework) as well as parts of the tiles. We have enumerated all possible methods of splitting each of the 400 natural tiles found in 248 known zeolite frameworks into halves and revealed 199 half-units that can play a role of building units in the zeolite assembly. We have showed that the observed intimate or epitaxial intergrowth of zeolite minerals can be perceived as a result of several possible ways of crystal growth with different methods of connection of the half-units from the same set. We have considered many zeolite pairs, for which the intergrowth was either observed or not revealed yet, and demonstrated that our model properly predicts and interprets the intergrowth phenomena.