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The article presents the results of qualitative and quantitative microstructural analysis, and the basic properties of clay soils subjected to long-term contamination by liquid petroleum fuels (LPF). Comparative study of undisturbed, contaminated in situ clay soil (CS) and reference uncontaminated soil (US) was performed. Soil contamination by these compounds causes transformation of microstructure and changes of geotechnical parameters. Microstructure is a key factor in the interpretation of soil properties. Microstructural analyses were performed with application of scanning electron microscope (SEM) and STIMAN software. It was estimated that contaminated soil is characterised by lower moisture content, plasticity, pH and zeta potential, and by higher bulk density and consistency index. Due to hydrocarbon contamination, soil microstructure changed from highly anisotropic mixed laminar-turbulent into uniform matrix type. Comparative quantitative analysis of the microstructure indicated redistribution of the pore space expressed by changes in porosity, pore number and shape, decrease of microporosity, and increase of elongated mesopores number.

The performed investigations were focused on analysing the variability of geological-engineering properties in clay soils from central-eastern Europe with regard to microstructures. Thirty-nine soils differing in origin, lithology and microstructure type were selected for analysis. Results of studies on lithological and physical and mechanical parameters were analysed, coupled with quantitative microstructural parameters based on microstructure images. The relationships between lithological, physical and mechanical and pore space parameters were determined with regard to microstructure types. Sediment origin and diagenesis, and soil microstructure and pore space parameters had influence on the geological-engineering properties. Such approach allows for predicting engineering parameters based on soil microstructure types and their pore space parameters.

The paper presents the basic problem related with practical application of carbonate rocks in construction: are carbonate aggregates produced from such rocks favorable for building engineering, particularly for road design and construction? To resolve this problem, (1) the geological-engineering properties of aggregates are presented, (2) the correlation between petrographic and engineering parameters is shown, and (3) a strict correlation between the geological-engineering properties and the freezing-thawing and crushing resistance is recognized. This knowledge has allowed to assess the usefulness of asphalt concrete (AC) made from dolomite and limestone aggregates in the design and construction of road surface structures. The petrography was characterized using optical microscopy and scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscope (EDS). Engineering properties were determined in accordance with European and Polish norms and guidelines. Statistical and design calculations were performed using dedicated software. The petrographic properties, and selected physical and mechanical parameters of the aggregates, were tested to show their influence on the freezing–thawing and crushing resistance. Strong functional relationships between the water adsorption, and the freezing–thawing and crushing resistance have been observed. Aggregate strength decreased after saturation with increasing concentrations of salt solutions. Calculations of AC fatigue durability and deformation allow for reducing the thickness of the road surface structure by about 20% in comparison to normative solutions. This conclusion has impact on the economy of road design and construction, and allows for a rational utilization of rock resources, which contributes to sustainable development of the construction industry.

In this paper, nano-hybrid particles of Ag@Fe2O3 based on O-carboxymethylchitosan were successfully synthesized using different reducing agents (NaBH4, sucrose) and without reducing agent. The smallest silver nanoparticles were those prepared without reducing agent (∼5±3nm). The average size of silver particles prepared with NaBH4 is around 5-15nm, and for samples prepared with sucrose, the average particle size is 10-25nm. The magnetization curves are roughly reversible, indicating that γ-Fe2O3 nanoparticles transit to a superparamagnetic state. Nanocomposites subjected to antimicrobial tests showed great antimicrobial activity against gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria, and good activity against the yeast Candida albicans and resistant strains of Staphylococcus aureus. The antibacterial behavior as a function of time was investigated in microbial growth kinetics, and the best nanocomposite was the one without reducing agent, which completely inhibited microbial growth for 48h.

The Tell el-Retaba archaeological site is located in the middle part of Wadi Tumilat, which extends along the north-eastern margin of the Nile Delta. It contains fragments of fortified and domestic objects of the ancient fortress and other constructions built of mud bricks. The establishment and functioning of the fortress is dated at the times of the reign of two great pharaohs, Ramesses II and Ramesses III (13th and 12th centuries BC). The grain size composition of the sediments used for mud brick production had significant influence on their physical and mechanical properties, which was used by the ancient Egyptians for the improvement of bricks. The finest fractions, clay and silt, which generally comprise clay minerals and organic matter played a significant role. These components significantly influenced the mud brick properties and resulted in a structural cohesion of the material. The second important component of mud bricks were coarse fractions – sand and gravel. The source of material used for brick production were the natural sediments located in the vicinity of the fortress, i.e. the Holocene lake clay and the Pleistocene gravel and sand of the gezira formation, deposited by a braided river. Clay sediments have a variable lithology as can be deduced from grain size composition of mud bricks and their properties. This variability was caused by a variable regime of the Nile, which supplied material to the lake basin. Geological studies were used to recognize ancient environment and morphology of the area, and to find clay, sand and gravel open-pits that existed in the area. The fortress site was selected optimally in relation to the landscape morphology and close vicinity of the source of basic material and water used for mud brick production. The area around the fortress was substantially transformed by humans due to settlement.

Closed depressions are reported in loess landscapes in various parts of Europe. The anthropogenic and natural origin of closed depressions is highly debated in literature. Closed depressions are an important component of the landscape in loess areas of the Lublin Upland. Furthermore, they perform the role of local closed sediment basins, creating unique conditions for the preservation of soils and colluvial sediments, along with the record of the evolution of the Holocene landscape, occurring under the influence of climate changes and human activity. The study objective was to evaluate the contribution of natural and anthropogenic processes influencing the origin and evolution of closed depressions. The Naleczow Plateau is composed of loess, whose thickness varies from a few meters to > 30 m. 1761 closed depressions have been documented within the Naleczow Plateau (493 km 2 ). A detailed investigation was conducted within selected closed depression, dissected by a deep and long road trench. The studied form was 40 m long, 26 m wide and 0.7 m deep. The analyzed exposure; 20 m long and 7 m high, presents a cross-section of the closed depression. Fieldwork and subsequent laboratory analyses were conducted: morphological, micromorphological, microstructural, geochemical, physico-chemical, OSL and 14 C dating. Archaeological and historical correlations were also performed. The primary bottom and slopes of the studied depression are composed of loess in situ, overlain by Late Glacial-Holocene fossil soil. Periglacial structures, such as deformed ice-wedge pseudomorphs, cracks and lenses macro-structures were documented in the loess and palaeosol at the bottom of the closed depression. The depression is filled with Neoholocene soil-sediment sequences consisting of 2 layers of colluvial sediments, separated by Neoholocene subfossil soil. They constitute a record of the two stages of CD infillings in the Holocene, connected with human agricultural activity, lasting from the Neolithic up to modern times. A detailed analysis of the loess, Late Glacial-Holocene fossil soil and Holocene colluvial sediments made it possible to distinguish the stages of evolution of closed depression influenced by changing environmental conditions and human activity, during the Late Glacial and Holocene.

The selected parameters of the Wartanian and Odranian tills, with relation to their spatial occurrence, grain size distribution, mineralogical composition, matric suction and other physical characteristics, are presented. The assessment of the lithogenesis and stress history on the microstructure is attempted. The comparison of the compression and permeability characteristics from field and laboratory tests has been performed. Laboratory consolidation tests carried out with up to 20MPa vertical stress, revealed two yield stress values, one in the range of a couple hundreds kPa, the other in the range of a couple thousands kPa. Based on those results, the reliability of the soil preconsolidation assessment, with the use of the two different methods is discussed. The aspect of the triaxial strength reduction under the dynamic loading of diverse frequency and amplitude is raised. The research results depict a variety of possible geological-engineering characteristics, under the divergent constraints scenarios, of compression or strength weakening origin. The effects of the specialized research program will widen the possibilities of physio-mechanical and structural characterization of soils for geological-engineering purposes.

The archaeological site Tell el-Retaba in north-eastern Egypt, about 35 km to the west of Ismailia city, is located in the middle of Wadi Tumilat, a shallow valley running from the Nile Delta to the Bitter Lakes, along which flows the Suez Canal. In ancient times the valley was a route between Egypt and Syro-Palestine, strongly fortified in the New Kingdom times (16th–11th century BC). Mud bricks were analyzed from two parts of the Wall 1 (core of grey-brown bricks and inner extension of green bricks) in a fortress which existed during the Ramesses II times. Grain-size composition of the studied bricks was almost identical in both parts of the wall, suggesting the same source material for a production of brick. However, significant differences were observed in physical and mechanical properties (uni-axial compressive strength) in both types of bricks. Bricks from the core had lower bulk density, higher porosity and soak faster, whereas their resistance parameters were much lower than those of the bricks from the inner extension. The reason for such large differences in brick properties was a technology of their production, particularly proportion of components, water volume added during brick formation or density degree. Brick preparation and in consequence, physical-mechanical properties had direct influence on preservation of defensive structures during environmental changes related to changes of groundwater and surface water levels or of precipitation. Ancient Egyptians responsible for construction works in mud brick structures of the fortress must have had good knowledge and experience. This could be observed particularly for the heaviest and most important construction element that is the defensive wall, founded on well-densified deposits. It was also testified by higher resistance of green bricks from the inner extensions, which probably originated slightly later and were intended to reinforce a weaker core built of grey-brown bricks.

Faience objects produced from the fourth millennium BC in ancient Egypt are considered as the first high-tech ceramics in human history. Despite extensive studies on manufacturing technology, many aspects of this complex technology remain a mystery and there is no methodology in place to unravel the techniques of Egyptian faience object production. Detailed studies presented herein fill the gaps, verifying standing opinions and allowing certain aspects of faience manufacturing technology to be reconstructed. The object of this innovative investigation is a hemispherical faience bowl discovered by archaeologists excavating a Ptolemaic workshop district at the site of Tell Atrib in the southern Nile Delta. The multiproxy analysis included the application of specialised software and preparation techniques coupled with complementary methods of light and digital microscopy, SEM with EDS, XRD, STA with EGA, as well as image analysis. Sources of raw and accessory materials (mineral and organic binders, fluxes, colourants) used for preparing the silica paste and glaze slurry were determined. The results helped to reconstruct how the raw material was prepared and how faience vessels were made. The bowl was moulded by compression using a two-part mould. The moulded and dried bowl was then covered by glaze slurry using the application method. A synthetic colourant, Egyptian Blue, was probably used to colour the glaze. The item was fired once at a temperature of 1050&ndash, 1150 &deg, C. Oxidised conditions were maintained in the kiln during the firing process and firing at the maximal temperature was relatively short. Application of the multiproxy approach has shed light on the technological aspects of faience bowl manufacturing. The obtained results have confirmed the usefulness of the comprehensive methodology that was applied for the reconstruction of particular manufacturing stages of faience objects.

Fly ash and bottom ash from thermal power stations are industrial wastes which are susceptible to weathering in the environment. First manifestations of transformations occur immediately after deposition of ashes in a disposal site and they continue in technogenic soils (Technosols) developing from the ashes on surfaces of such sites. Technosols developed from bituminous coal and lignite ashes in Poland were studied in order (a) to identify the most important mineral transformations during the first several decades of soil development, and (b) to discuss the evolution of these soils. Mineral transformations can serve as good indicators of pedogenesis in the studied Technosols. Quantitative X-ray diffraction analyses, Fourier transform infrared spectroscopy, optical microscopy, and scanning electron microscope-energy dispersive spectroscopy studies showed that the mineral transformations proceeded more dynamically in Technosols developed from lignite ashes, whereas they were less expressed in soils formed from bituminous coal ashes. Technosols developed from bituminous coal ashes contained mineral phases inherited from ashes (aluminosilicate glass, mullite, quartz, magnetite, hematite, and traces of maghemite and barite) as predominating constituents. Small contents of pedogenic calcite, iron oxyhydroxides, and most likely short-range order Si- and Al-containing phases originated within ~ 60 years of pedogenesis. Technosols developed from lignite ashes contained aluminosilicate glass, quartz, hematite inherited from fly ash, as well as a variety of secondary minerals (vaterite, calcite, bassanite, gypsum, ettringite, hydrotalcite, and brucite) which were formed as an effect of rapid mineral transformations after ash deposition. After about 40 years, pedogenesis (accelerated by reclamation and a few years of intense cultivation) led to the formation of a new mineral assemblage with the predomination of calcite, gypsum, and hydrotalcite. A concept of evolution of the studied Technosols comprising four stages of evolution was proposed: I – formation of ash during combustion of fuel (coal or lignite) in a thermal power station, II – transport and deposition of ash in a disposal site accompanied by the first weathering alterations, III – early pedogenesis, and IV – further (predicted) evolution.

Particle shape raises more interest among geologists than among engineering geotechnical staff. It is commonly accepted that particle shape is the result of geological processes, such as transportation and sedimentation, and depends on many factors, such as mineral composition or structure and texture of the host rock. The influence of particle shape on the geotechnical properties of soil has been widely discussed in literature from the early 1900-ties, e.g. by Wadell [3], Riley [16], Pentland [6] and other scientists, who proposed their own definitions and methods of determining particle roundness and angularity. Finally, it has been decided that particle shape should be defined by three independent parameters [2]: roundness, reflecting the general shape of the particle in comparison to a sphere; angularity, describing changes in roundness in the corners of the studied particle; and microtexture, reflecting the complexity of the particle surface in micro scale; this parameter is also referred to as micromorphology. These three parameters describe particle shape at various magnifications and allow obtaining all important data on this feature. This report is focused on a review and analysis of the analytical methods determining particle angularity, and is an attempt to establish an optimal definition of determining particle angularity in road aggregates. We present selected definitions used to determine angularity, worked out by different authors over the years as an attempt to find the best analytical method of describing angularity.

The shape of particles building the solid phase of soils is an important factor influencing soil behaviour. Three parameters defining the characteristics of particle shape: roundness, angularity and texture are the most commonly analyzed. The most difficult issue is texture determination due to its complex nature. Quantitative evaluation of this parameter creates serious problems, however, is not impossible. A new mathematical tool, such as fractal geometry, may be helpful. Through the use of power law, fractal analysis allows to designate fractal dimension that specifies the complexity of the tested object.

Definition and studies on the shape of various bodies are an interdisciplinary issue, raising wide interest among scientists. In geology and geotechnics the studies refer to features related to the shape of soil and rock particles, especially of those used for practical purposes. Due to the complex shape of particles, its three components have been distinguished: sphericity, angularity and surface microtexture. Sphericity usually determines the degree of similarity of a given particle to a sphere, whereas defined as a form refers to the general shape of the particle [3]. Particle shape and parameters that characterise it have not been unequivocally defined and normalised, resulting in a large number of definitions and ways of their determination. An extensive paper presenting the definitions used to describe shape parameters has been presented by Szerakowska [13]. This paper is focused on the comparison of analytical methods and an attempt to select the most optimal method for determining sphericity of particles in construction and road aggregates.

Microstructural (fabric, forces and composition) differences due to hydrocarbon contamination in a clayey soil (glacial till) were studied using scanning electron microscopy (microfabric analysis) and sedimentation bench test (PSD). Uncontaminated and contaminated glacial till from NE Poland (in the area of a fuel terminal) were used for the study. Because the contaminated samples exhibited lower electric charge, the electrostatic repulsive forces in the contaminated samples were much lower than in uncontaminated samples. All sedimentary-based particle size test results gave similar results and were inconclusive to find difference between contaminated and uncontaminated samples. Mastersizer PSD data show smaller aggregates in contaminated in comparison to the uncontaminated sample. The present test's finding may support earlier microstructure investigation results, where diesel-contaminated clay soil shows more open porosity, consisting consequently of looser aggregates, which were easier dispersed in water during Mastersizer measurements than the more coherent uncontaminated clay sample. This in effect increased the percentage of finer than 0.1 mm grain fraction within the broad diameter range in contaminated samples results, in comparison with the uncontaminated sample results.

The Dry Moat is one of the most impressive and at the same time puzzling architectonic structure preserved within the famous royal necropolis at Saqqara, Egypt. It is a rock-hewn ditch about 40 m wide and of variable depth, which surrounds the Step Pyramid complex built by Pharaoh Djoser from the Third Dynasty which was the first monumental structure totally built of stone blocks in human history. The function and intention of the Dry Moat remained unknown prior to this study and was unique in the Old Kingdom (ca. 4600–4200 BP). The main focus of the ground-penetrating radar (GPR) survey conducted in 2012 was recognizing the course of the western section of the Dry Moat and determining the geometry of this structure. The GPR survey confirmed the effectiveness of the GPR method and determined that this vast architectural structure is a ditch surrounding the Step Pyramid. The western section of the Dry Moat was found to have a different geometry than previously thought. The stratigraphy of the infilling beds suggests that it is deeper in the western part than in the eastern one. In the light of conducted GPR prospection it seems likely that the Dry Moat served originally as the huge quarry for material used for construction of the Step Pyramid. It may have also had a secondary function that was purely religious in nature, as has been suggested by some scholars. The Dry Moat seems to be a unique stone work without any known analogies from ancient Egypt. Copyright © 2015 John Wiley & Sons, Ltd.

This paper presents the preliminary results of ground penetrating radar sounding applied at the desert archaeological site in Saqqara (Egypt). The survey was carried out in 2012 within a project realized by Institute of Archaeology, Cardinal Stefan Wyszyński University in Warsaw and the Faculty of Geology, University of Warsaw. One of the key aims of the research was testing the application of ground penetrating radar to non-invasive surveys of desert archaeological sites. Radargrams obtained for area of so called the Dry Moat channel surrounding the Step Pyramid complex have shown the geological structure of its filling. It comprises among others debris-sand conglomerate of diluval origin characterized by a significant content of the clay fraction and clay minerals. Such lithological content strongly attenuate the propagation of EM waves, restricting the depth range of the GPR survey. The conducted geophysical prospection west to the Step Pyramid in Saqqara has confirmed the high applicability of the GPR method in non-invasive studies of vast architectural structures, such as the monumental ditch surrounding the Step Pyramid known as the Dry Moat. It should summarised that high horizontal resolution obtained during GPR survey is a result of local geological structure of the searched area, i.e. strong lithological contrast of the sediments filling the Dry Moat, which, depending on their mineralogical composition

In this paper, nano-hybrid particles of Ag@Fe

Echinoderms are characterized by a calcite endoskeleton with a unique microstructure, which is optimized for multiple functions. For instance, some light-sensitive ophiuroids (Ophiuroidea) and asteroids (Asteroidea) possess skeletal plates with multi-lens arrays that are thought to act as photosensory organs. The origins of these lens-like microstructures have long been unclear. It was recently proposed that the complex photosensory systems in certain modern ophiuroids and asteroids could be traced back to at least the Late Cretaceous (ca. 79 Ma). Here, we document similar structures in ophiuroids and asteroids from the Early Cretaceous of Poland (ca. 136 Ma) that are approximately 57 million years older than the oldest asterozoans with lens-like microstructures described thus far. We use scanning electron microscopy, synchrotron tomography, and electron backscatter diffraction combined with focused ion beam microscopy to describe the morphology and crystallography of these structures in exceptional detail. The results indicate that, similar to Recent light-sensitive ophiuroids, putative microlenses in Cretaceous ophiuroids and asteroids exhibit a shape and crystal orientation that would have minimized spherical aberration and birefringence. We suggest that these lens-like microstructures evolved by secondary deposition of calcite on pre-existing porous tubercles that were already present in ancestral Jurassic forms., Institute of Paleobiology, Polish Academy of Sciences, Polonia, Oxford University Museum of Natural History, Reino Unido, Unidad de Zaragoza, Instituto Geológico y Minero de España, España, Unidad Asociada en Ciencias de la Tierra, Universidad de Zaragoza, España, Institute of Geochemistry, Mineralogy and Petrology, University of Warsaw, Polonia, Institute of Hydrogeology and Engineering Geology, University of Warsaw, Polonia, Department of Palaeontology and Stratigraphy, University of Silesia, Polonia

The use of mechanical sieves has a great impact on measurement results because occurrence of anisometric particles causes undercounting the average size. Such errors can be avoided by using opto-electronic measuring devices that enable measurement of particles from 10 μm up to a few dozen millimetres in size. The results of measurement of each particle size fraction are summed up proportionally to its weight with the use of Elsieve software system and for every type of material particle-size distribution can be obtained. The software allows further statistical interpretation of the results. Beam of infrared radiation identifies size of particles and counts them precisely. Every particle is represented by an electronic impulse proportional to its size. Measurement of particles in aqueous suspension that replaces the hydrometer method can be carried out by using the IPS L analyser (range from 0.2 to 600 μm). The IPS UA analyser (range from 0.5 to 2000 μm) is designed for measurement in the air. An ultrasonic adapter enables performing measurements of moist and aggregated particles from 0.5 to 1000 μm. The construction and software system allow to determine second dimension of the particle, its shape coefficient and specific surface area. The AWK 3D analyser (range from 0.2 to 31.5 mm) is devoted to measurement of various powdery materials with subsequent determination of particle shape. The AWK B analyser (range from 1 to 130 mm) measures materials of thick granulation and shape of the grains. The presented method of measurement repeatedly accelerates and facilitates study of granulometric composition.

The paper presents a case study of sediment, termed soft lodgement till (a product of subglacial deposition by active ice), described previously on the basis of macro-evidence from Poland and Canada but not yet studied in detail in one particular site. The till at Anielinek (about 7 m thick) was examined by macroscopic observation, thin section description, and qualitative and quantitative scanning electron microscopy (SEM) analyses. It shows a macroscopic massive structure and overlies a flat top of glaciolacustrine sediments. These sediments form upward intrusions within the till—owing to the existence of reversed density gradients among the deposits—and the upper parts of the intrusions are tilted in consistent directions within the successive parts of the till. Moreover, SEM images also record uniformly oriented microintrusions within this diamictic material. The occurrence of these macro- and microstructures within the successive parts of the till point to an almost continuous process of intrusion during ongoing deposition of the till and to water saturation of the subglacial environment. Such conditions reduced friction of the glacier bed against its substratum, and glacial debris must have been mainly melt-released from the moving glacier base. This process was responsible for deposition of sediment (soft lodgement till) that was immediately and continuously deformed by glacial stress during the ongoing accretion of debris from the glacier base.

Macroscopic observation, thin-section analysis and electron microscope study were used in a detailed examination of till exposed in a valley escarpment. The till displays two kinds of bedding: (1) beds of different colour (lithology) that are not separated from one another by distinct boundaries, and (2) beds that are separated by distinct subhorizontal planes of discontinuity, commonly consisting of several beds of the first type. Beds showing no clear separation are interpreted as having been deposited through continuous lodgement, while the distinct discontinuities most probably record sliding planes of the glacier sole during breaks in till deposition. These features, along with the qualitative and quantitative microscopic evidence, indicate that the lower and middle parts of the till were deposited by hard lodgement. The process of deposition was interrupted several times by episodes of non-deposition, some of them accompanied by glacial erosion. The upper part of the till was deposited by continuous lodgement that was transitional between hard and soft lodgement processes. Such a succession indicates the prevalence of a cooler subglacial thermal regime which changed upwards into a milder one. The till examined displays mainly brittle deformation – namely Riedel shears that are primarily concentrated between the subhorizontal discontinuities characteristic of the lower and middle parts of the section. A dense set of Riedel shears also cuts thicker portions of the upper part of the till and, in some places, such shears combine along additional subhorizontal (discrete) shear planes. The direction of the fractures, as well as the strong fabric orientation of stone a-axes within the till, indicate an ice flow in the studied area from NW to SE.

The Tell el-Retaba archaeological site is located at Wadi Tumilat, a shallow valley running from the Nile Delta to the Bitter Lakes. In ancient times, a route connecting Egypt with Syria-Palestine ran across the site. In the 13th century BC, during the rule of Ramesses II, a fortress surrounded by “Wall 1” was erected and in times of Ramesses III in the 12th century BC, a larger fortress surrounded by “Wall 2” and “Wall 3” was constructed. Using the finite element method (FEM) and ZSoil 2D&3D software, the wall heights were modelled and their soil-structure interaction was analysed. Strength of the wall depended on size and strength of bricks and mortar, brickwork, wall shape and foundation. Ancient builders using mud bricks must have known from practical experience the essentials of a wall construction, in which the height to width ratio was at 1.75 to 1.85. Moreover, they must have related the engineering properties of the material with the height of the construction and its purpose. The width to height ratio must have been used and related by ancient Egyptians to the ground resistance. Modelling has shown that, at wall width of 5 m, the foundation would have lost its stability at wall height of 13–14 m and bricks from the lower part of the wall would be destroyed. According to the undertaken assumptions, in order to retain stability, the wall height must have been limited to about 8–9 m.