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Fe-Cu-Co is a structural component used in applications requiring both high strength and high hardness. A diamond cutting tool with iron -based (Fe -53%, Cu – 28%, Co -17%, P– 1% & Ni -1%) pre-alloyed powders was prepared in the laboratory using powder metallurgy technique. Commercially available pure powders were combined to create the alloys, which were then roll compacted into bars and right away hot processed into fully dense alloy bars. Solid state sintering technique is used to manufacture composite material as it gives less defectives, more accurate than casting and excellent dimensional control. During sintering process metal powders are blended in ball milling and are compacted on hot press machine by applying heat and pressure simultaneously at different elevated temperatures. The sintered specimens are subjected to hardness, impact, density and porosity tests along with fractography study. From experimental observations it is found that material has high hardness than the steel, which can withstand mechanical vibrations, high impact strength and high toughness. According to experimental results it is most suitable for cutting applications, and there is a possibility to add diamond crystals in this tool, to strengthen hardness helping to cut the rocks.

The mechanical behaviour of fibre-reinforced sands (FRS) has been thoroughly explored with a laboratory study, firstly investigating the influence of relevant parameters such as grading index, soil density, amount, diameter, and length of fibres then focusing on their orientation with respect to the principal stress directions. This aspect has been deeply investigated performing parallel tests on samples of pure sand and on samples with randomly and uniformly oriented fibres compacted at a similarly high relative density (Dr≈1). Direct and triaxial shear tests have been performed, the former enforcing deformation on a predetermined shear plane. The results show that reinforcement with oriented fibres provides a higher strength and ductility to the sand. The grain scale investigation of the materials’ response to direct shearing has been carried out performing X-ray tomography post-mortem (i.e., after the test). The evolution of porosity in several samples prepared with the same procedure and sheared under the same conditions has been studied freezing the material fabric with nanosilica grout injected at different displacement levels. On the contrary, X-ray tomography performed along with miniature triaxial tests (operando method) enabled the analysis of the spatial distribution of deviatoric strain too. In both cases, maps show the relevant role of fibres orientation with reference to the shear band. If adequately activated, fibres tension modifies the strain field in the samples, preventing the fragile rupture along a shear plane and transferring the stresses to the outer soil portions, in this way providing a more dilatant and ductile overall response of the reinforced material.

The article analyzes the methods for substantiating the final oil recovery factor in various regions of the world. The advantages of methods for determining recoverable oil reserves according to the development of objects are shown, but the use of determining the oil recovery factor by extrapolation and hydrodynamic methods at an early stage of field exploration is practically impossible due to the lack of information about the necessary geological and field parameters.

Over the years, Oil spillage has been drastically affecting our ecosystem. It is quiet unfortunate that Settlers in these places always live an unhealthy lifestyle especially during the raining season. There is no other reason for this than the poor spatial data to support and guide safe exploration. To spatially provide solution to this problem using GIS and remote sensing techniques, constitute the major drive for this research. The objective of this work was to determine the geographical extent of bitumen locations as well as to assess its hazard vulnerability in the study area. Differential Global Position System was used to acquire the coordinates of bitumen location and subsequently, the coordinates was used to download SRTM Digital Elevation Model from USGS which was used for the assessment of the hazardous effects of bitumen in the study area through hydrological analytical method. It was discovered that the total area occupied by land use was 875.50 km2 and out of which 88.08km2 (10.15%) was affected by bitumen. The result of physical property test conducted were adjudged good when compared to the established standard while the chemical property test revealed high concentrations of Silicon Oxide which is injurious to health despite its suitability for construction industries. The study recommends that this research should serve as a guide in finding lasting solution to communities already affected and also settlements that are prone to bitumen hazard before it escalates further so as to protect lives, properties, and natural habitats in the study area.

Understanding subsurface flow, especially in partly karstified rock formations mainly housing water through a few preferential pathways, is still challenging. This point is the consequence of the poor accessibility of the subsurface and lack of accurate depictions of water bearing bodies and distributions. This notwithstanding, highly-resolved geophysical investigations bring new images of the subsurface.A 3-D seismic survey with shots and wave monitoring at the surface is carried out over a subsurface karstified reservoir located at the Hydrogeological Experimental Site (HES) of the University of Poitiers (France). Processing the 3-D data, in association with wave velocity calibration from vertical seismic profiles (VSP) recorded via geophones in wells, renders a 3-D velocity block. The velocity block is then converted into pseudo-porosity values revealing three high-porosity, presumably water-productive, layers, at depths of 35–40, 85–87, and 110–115 m.In addition, full wave acoustic logging (FWAL) can detect, close to wells, porous or open bodies that are too small for being captured by the spatial resolution of 3-D seismic images. A FWAL can also confirm or invalidate data from VSP recorded via hydrophones.The block of pseudo-porosities is compared to a different representation of the subsurface in the form of hydraulic conductivity distributions (or hydraulic diffusion) obtained by slug tests or by inversion of transient interference testing between wells. The inverted hydraulic conductivity maps do not match up the distribution of porous bodies identified by seismic data. This poses the question of guiding conventional inversions on the basis of a prior guess as the subsurface structure obtained via geophysical investigations.

Sports have received great attention in the Kingdom of Saudi Arabia’s vision 2030, as it was stated that the government will support sports of all kinds, and expand opportunities associated with this trend. As a result, Saudi women have increased their interest in outdoor sports activities, which has led to a growth in the production of the sports abaya. A sports abaya is worn over daily clothes while outdoor-exercising. The presence of multi-layers of clothing negatively affects the fabric’s air permeability. Therefore, fabrics used in sports abaya must be highly air permeable, to allow the transference of heat and moisture from the skin surface to the environment. The present study aims to investigate the effect of structural properties and porosity on the air permeability of the sports abaya fabrics. Two variable samples of fabrics (100% knitted cotton -white, 100% woven polyester -white) and two fixed samples (100% knitted cotton -black, 100% knitted polyester -orange) were used in producing and testing two models of sports abayas, with solo variable between the models. It was found from the results that, through a comparison between the variable samples, 100% woven polyester-white recorded a better air permeability value of 44.9 ml/cm2/s, and porosity of 109.23 pixels / mµ2, than 100% knitted cotton-white. This is due to the fact that the 100% woven polyester fabric has a higher porosity, and is made of fine polyester yarn. The results confirm that the use of 100% woven polyester-white fabric in producing sports abaya will provide greater comfort for the wearer for his ability to transfer heat and moisture well in terms of air permeability. Therefore, sports abaya model, which contained a 100% woven polyester fabric sample, was superior to the sport abaya model that contained 100% knitted cotton fabric in the level of air permeability. The results of the current study confirmed the existence of a direct-proportion relationship between the fabric’s air permeability and its porosity, and an inverse relationship with some structural properties. The study also found out that the use of net fabric in the production of the sports abaya will greatly improve comfort in wearing, due to its high air permeability.Keywords: Thermal comfort, Air permeability, Physical properties, Porosity.

This study was conducted to identify the extent of the possibility of using clays in southern Libya (north and south of the Ashkeda region, which were coded in the research (A1, B2), and the Tarout region symbolized (C3), for various industrial ceramic uses, through the identification of the physical and chemical properties where it was conducted Laboratory tests (plasticity modulus analysis, water additive analysis of the used slurries, granular gradient analysis using laser, XRF LAB chemical analysis, TDA, DTA, X-ray analysis X-RAY, XRD), to identify the specifications of the clays used. Clays at different temperatures (950 ° C, 1000 ° C, 1050 ° C, 1100 ° C, 1150 ° C) to identify the appropriate degree of maturity by measuring the degree of (density, porosity and water absorption, total shrinkage, color gamut) by reaching the highest density ratio, the lowest porosity, absorption and the highest hardness strength .It is evident through the laboratory tests and analyzes that were conducted for the three clays (A1, B2, C3), which showed that the regions of southern Libya had a variety of deposition environments, and thus the diversity of the mineral deposits present in them, which resulted in the difference in the type of clays obtained, which is that of the Tarout region (Kaolin type) It is considered one of the remaining primary clays (primary / residual), meaning that it was formed and settled in its original place, and it is due to the type of WSCH according to the Libyan specifications. It is classified from clays with medium thermal resistance and the temperature does not exceed (1400 ° C) and according to the optical parameter it is white in color) Tine of the Ashkeda region (a type of earth mud, which is mostly sedimentary mudflats formed in different geological eras, so that it became easy to classify it according to the geological components, and it is a non-thermal clay located between the thermal limits of (950 CO – 1000 CO).

Over the years, Oil spillage has been drastically affecting our ecosystem. It is quiet unfortunate that Settlers in these places always live an unhealthy lifestyle especially during the raining season. There is no other reason for this than the poor spatial data to support and guide safe exploration. To spatially provide solution to this problem using GIS and remote sensing techniques, constitute the major drive for this research. The objective of this work was to determine the geographical extent of bitumen locations as well as to assess its hazard vulnerability in the study area. Differential Global Position System was used to acquire the coordinates of bitumen location and subsequently, the coordinates was used to download SRTM Digital Elevation Model from USGS which was used for the assessment of the hazardous effects of bitumen in the study area through hydrological analytical method. It was discovered that the total area occupied by land use was 875.50 km2 and out of which 88.08km2 (10.15%) was affected by bitumen. The result of physical property test conducted were adjudged good when compared to the established standard while the chemical property test revealed high concentrations of Silicon Oxide which is injurious to health despite its suitability for construction industries. The study recommends that this research should serve as a guide in finding lasting solution to communities already affected and also settlements that are prone to bitumen hazard before it escalates further so as to protect lives, properties, and natural habitats in the study area.

This article uses adhesives or what I am calling here ‘sticky matter,’ to illustrate multispecies relationships in Macao, a subtropical coastal region in South China. It focuses primarily on a traditional rammed earth material known as chunambo in Macao and other former Portuguese colonies. Composed of oyster shell, straw, rice, local soils and sand chemically bounded together by slacked lime, this precursor to modern day concrete has a unique combination of porosity and structural integrity that makes it particularly adaptable to tropical climates and a contrast to contemporary building practices which are often designed to create sealed interior environments. Discussions of porosity within New Materialism, Urban Studies and Chinese aesthetics will be used to think stickiness alongside questions of material integrity in the face of sea level rise, erosion and anthropogenic forces. Much like limestone sediments formed over the course of thousands of years at the bottom of ancient tropical sea beds, chunambo invites speculation about material permanence in the face of climate futures and a changing urban environment.

The filtration properties in solid–liquid separation mainly depend upon the filter cake properties, for instance, cake resistance. However, particle size distribution, particle shape, and their arrangements significantly impact cake filtration. This paper aims to review the work done so far and collate both fundamental and applied work with regard to the quantification of cake properties. The cake resistance and cake porosity in terms of shape, as well as varying particle size distribution width, are discussed here. This work summarizes the current state of the technology and recommends advancements and improvements for future research.

Chemistry of porous organic cages has developed in the past decade as an alternative to the wellknown nanoporous materials based on extended networks, such as metal organic frameworks (MOFs) or covalent organic frameworks (COFs). Unlike these extended polymeric materials, the molecular nature of organic cages offers important advantages, such as solubility of the material in common organic solvents. However, a simultaneous combination of porosity and additional optoelectronic properties, common in MOFs and COFs, is still quite rare. Therefore, porous organic cages are relatively underdeveloped when compared to MOFs and COFs. Here, we highlight the rich possibilities the porous organic cages offer and discuss the recent development where interesting photophysical properties augment the porosity, including our own work.

The limited deposits of natural wollastonite in our country and the labor intensity of its extraction and processing, make promising the development of methods of its synthesis based on various types of domestic plant and fossil raw materials, especially industrial waste. The use of rice husk ash and calcium oxide in the solid-phase synthesis of calcium silicates ensures the content of β-wollastonite in their composition at the level of naturally-occurring Miwoll10-97. The obtained results indicate greater efficiency of amorphous silicon dioxide for the synthesis in the solid phase of calcium silicates. Synthetic calcium silicates, like naturally occurring wollastonite, have a pronounced alkaline surface nature, with the acid-base characteristics not influenced significantly by the sintering temperature, as well as the type and ratio of initial components. Calcium silicate produced from zeolite-siliceous rock has the smallest particle size and the narrowest particle size distribution, i.e. the most homogeneous structure. All investigated calcium silicates increase the wear resistance of epoxy materials, and low-porous silica sand-based fillers are more effective, providing high resistance of filled epoxy materials to climatic factors as well.

This article examines the use of waste rice processing as a promising fillers for PVC finishing materials. Due to the presence of amorphous silicon dioxide these fillers improve the performance properties of filled PVC, while lignin and cellulose in their composition accelerate biodegradation when buried in the soil. The use of these wastes allows solving the problems of “green” chemistry and closed-cycle economy and reducing the cost of finished polymer products. The paper studies the effect of ash of rice husk and synthetic wollastonite on its basis on the diffusion processes occurring during mixing of PVC and plasticizer. Activation of the RHA surface by CATAPAV significantly affects its elemental and particle size distribution and structure porosity, leading to a decrease in the porosity of the filler, reducing its particle size and narrowing the distribution of particles and pores in size. At use of silicate fillers of optimum composition growth of tensile strength, thermal stability and decrease of plasticizer migration from PVC compositions, owing to plasticizer retention in pores of these fillers is reached.

It has been shown that the addition of hydrophilic polyarylatepolyalkylene oxide and polyethersulfone-polyalkylene oxide block copolymers to polyethersulfone can control the porosity of the selective layer of hollow fiber ultrafiltration membranes. The selection of the optimal amount of the additive makes it possible to increase the performance of membranes in the purification of drinking water from microalgae, large mineral particles, bacteria and viruses.

A continuum model of fracture that describes, in principle, the propagation and interaction of arbitrary distributions of cracks and voids with evolving topology without a “fracture criterion” is developed. It involves a “law of motion” for crack tips, primarily as a kinematical consequence coupled with thermodynamics. Fundamental kinematics endow the crack tip with a topological charge. This allows the association of a kinematical conservation law for the charge, resulting in a fundamental evolution equation for the crack-tip field and, in turn, the crack field. The vectorial crack field degrades the elastic modulus in a physically justified anisotropic manner. The mathematical structure of this conservation law allows an additive “free” gradient of a scalar field in the evolution of the crack field. We associate this naturally emerging scalar field with the porosity that arises in the modeling of ductile failure. Thus, porosity-rate gradients affect the evolution of the crack field, which then naturally degrades the elastic modulus, and it is through this fundamental mechanism that spatial gradients in porosity growth affect the strain energy density and the stress-carrying capacity of the material and, as a dimensional consequence related to fundamental kinematics, introduce a length scale in the model. A key result of this work is that brittle fracture is energy-driven while ductile fracture is stress-driven. Under overall shear loadings where the mean stress vanishes or is compressive, the shear strain energy can still drive shear fracture in ductile materials.

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Copyright of Écrans is the property of Classiques Garnier and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The textile industry uses large amount of water and organic dyes to tint their products. These synthetic dyes are toxic and cause water coloring. This results in colored wastewater that must be treated before being discharged. In addition, most dyes are not biodegradable, and once released they alter the aquatic environment. Among the processes for treating these effluents, adsorption is an easy and a costeffective process to implement. The objective of this study is the preparation of biochars from common reed applicable for the discoloration of effluents used in the textile industry. Common reed (Phragmites australis) has been collected from the Sed-Ksob river of M'sila (Algeria) and used as precursor for the production of biochars activated by phosphoric acid. The surface chemistry of the prepared materials has been characterized using selective titration (Boehm assay), TGA analysis and pH of point zero charge (pHpzc) measurements. The porous texture has been investigated by using methylene blue adsorption and iodine number measurements. The results of the TGA analysis and the Boehm assay show the presence of many superficial functional groups on the surface of the biochars. The amount of oxygenated functional groups on all the prepared biochars depends on the impregnation ratio of phosphoric acid, except for the one obtained at 150% impregnation ratio. The adsorption of methylene blue and the iodine test indicate an increase in the specific surface area with an increase in the impregnation ratio due to the development of the microporosity and the mesoporosity. The adsorption properties of methyl orange, an anionic dye, were studied on the prepared biochars as function of concentration, contact time, and temperature. The Langmuir model describes well the equilibrium adsorption of methyl orange on the prepared biochars. The adsorption kinetics are described by the pseudo-second order and the liquid film diffusion models. An endothermic physical adsorption of methyl orange on the prepared biochars has been highlighted. [ABSTRACT FROM AUTHOR]

Copyright of Synergies Mexique is the property of GERFLINT (Groupe d'Etudes et de Recherches pour le Francais Langue Internationale) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Présence Francophone is the property of College of Holy Cross, Department of Modern Languages & Literatures and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Certaines stratégies langagières mises en reuvre par André Bucher sont aptes à suggérer la per- méabilité du réel, vu que l’homme, l’animal et les forces naturelles sont des actants interdépen- dants dans sa fiction. Des configurations de style tentent de suggérer les enjeux de cette interver¬sion environnementale : la personnification des éléments naturels à l’aide de métaphores filées ou de la catachrèse tente de restituteur un vocabulaire propre à l’animal. Néanmoins, en estompant un lyrisme excessif, Bucher insiste sur le fait que le plan de l’homme est incommensurable à celui de la nature.

Cement-concrete pavements of roads and airfields are the most durable type of pavement. The design service life of cement-concrete pavements is 40-50 years, in Russia this period is 20-25 years, and for asphalt-concrete pavements is 10-15 years. The real, actual overhaul period of asphalt concrete pavements, is much lower than the design one (according to the Federal Road Agency of Russia «Rosavtodor», on average, 3-5 years or even less), therefore, work aimed at increasing the durability of cementconcrete pavements is of particular relevance. The main technical parameters of road concrete that characterize its durability are compressive strength, flexural tensile strength, water absorption and others. The most important parameter is the frost resistance of concrete, which is primarily influenced by the structure of the pore space. This paper shows the way of obtaining concretes based on aggregates, the frost resistance of which is lower than the frost resistance of the resulting concrete.

In this article the issue is to analyze the impact of media intervention in socio-political crises. The article postulates that in crisis situation, the act as catalyst worsing the atmosphere or function as regulator by contributing to peace and social cohesion consolidation. As far as this article is concerned, the lack to deontology and professional ethics in Togo media and the porosity of their limit with politicians compel to identify them as catalysts socio-political crises in Togo. [ABSTRACT FROM AUTHOR]

Copyright of Matériaux et Techniques is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A Re-containing single-crystal superalloy was used to research the high temperature low stress creep behavior. Transmission electron microscope, scanning electron microscope and some other research methods are employed. The results and analysis are summarized below: Two mechanisms for the steady creep are found in this experiment. The volume fraction of pores after creep test at 1100°C increased more than 2 times compared with that before test, but the increasing at 1000°C is relatively small, which reveals that temperature has an great influence on the formation of pore during creep; There are two types of pores associated with fracture during the creep process. One is the casting shrinkage located between the interdentritic, which is formed in the solidification of the alloy. Another type of pore is nucleated and growing during the creep deformation.

The present work aims to study the potential valorization of composts exhausted cunicoles for aboveground vegetable plants. In a device complete random block with three repetitions, five composts in a pure state or in mixture and a witness are tested under tomato in seedbed except ground. They got results enable us to confirm that the composts are mature. As a whole, they have availability out of high water and a content of relatively weak air, whereas the substrates containing the peat-compost mixtures have physical properties close to the standards retained in Tunisia. The vegetative behavior of these plants with respect to the variation of the composition and the average size of the particles of the substrates shows a sensitivity of the seedlings to these parameters to the beginning of their growth. Majority of the mixtures containing peat-compost gave seedlings of quality, healthy, and homogeneous. The composts prepare well with a partial use in except ground.

Copyright of Matériaux et Techniques is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The laser filament winding of preimpregnated thermoplastic tapes requires a multiphysical analysis, leading to the control of transformation parameters. Such an analysis is generally carried out by considering the raw material, the tape, as a "standard material". Consequently, conclusions can be biased due to the material variability, which presents at least a natural variability, at worst local or repeated defects. Therefore, in the present work, the subject under study is the thermal behavior of the tape, independently of the manufacturing conditions. The detected thermal irregularities are then put into perspective with the irregularities of the material, such as thickness variations or porosities. [ABSTRACT FROM AUTHOR]

The paper considers interaction between gas-kinetic and physicochemical parameters in coal seams, which conditions coal and gas outbursts. The laboratory and field test data on interaction between geomechanical and physicochemical processes in coal seams are presented for various rank of coals from Kuzbass. The areas of higher coal and methane outburst hazard feature bifurcation in porosity, moisture content and methane absorption of coal from different operating mines in the Kuznetsk, Donets and Lvov–Volyn Basins. Bifurcation consists in the alteration of gradients of these values. At the bifurcation point of these parameters, a coal-and-methane seam can generate a disturbing gas-dynamic impulse sufficient for coal self-destruction. This property explains unexpected nature of coal and gas outbursts.

In this paper, we elaborated the nickel-based alloy type Hastelloy G30 and we analyzed it by techniques of characterization in order to interpret the results obtained through a computer simulation. The calculation of the thermo-physical properties of the alloy and the simulation of filling and solidification of the casting was performed by the software ProCAST. The validation of the numerical results was done by the following experimental techniques: optical microscopy and hardness test. In the center of the elaborate piece, the experimental results showed the appearance of porosity and leading to embrittlement of the alloy. According to the numerical simulation, this is caused by a fraction of the liquid that remains trapped in this area.

It has done a study of porosity prediction by using neural network. The study uses 2D seismic data post-stack time migration (PSTM) and 2 well data at field “T”. The objective is determining distribution of porosity. Porosity in carbonate reservoir is actually heterogeneous, complex and random. To face the complexity the neural network method has been implemented. The neural network algorithm uses probabilistic neural network based on best seismic attributes. It has been selected by using multi-attribute method with has high correlation. The best attributes which have been selected are amplitude envelope, average frequency, amplitude weighted phase, integrated absolute amplitude, acoustic impedance, and dominant frequency. The attribute is used as input to probabilistic neural network method process. The result porosity prediction based on probabilistic neural network use non-linear equation obtained high correlation coefficient 0.86 and approach actual log. The result has a better correlation than using multi-attribute method with correlation 0.58. The value of distribution porosity is 0.05–0.3 and it indicates the heterogeneous porosity distribution generally from the bottom to up are decreasing value.

In the present study, the simulation of the direct carbon fuel cell (DCFC) using a hybrid Lattice Boltzmann and finite volume approach is performed. The numerical model was first validated against available experimental data. Parametric studies were carried out to investigate the effect of the microstructure of the carbon fuel on the DCFC performance. The increase of the specific surface area (SSA) or porosity was found to minimize the voltage drop in the cell and ameliorate its output power density. In contrary, the increase of the tortuosity was found to inversely affect these results.

In this paper, an analytical solution is presented for vibration behaviour analysis of functionally graded materials plates (FGM). During manufacture of these plates, defects such as porosities can appear. Those can change the entire behaviour of these plates. A method based on a higher shear deformation theory will be presented to study the free vibration of FGM plates resting on elastic foundation. Two different porosity distributions through thickness direction of plate will be retained. The elasticity moduli and mass density of these plates are assumed to be graded in the thickness direction according two distribution patterns. The governing equations are obtained through the Hamilton's principal and the closed form solutions in terms of natural frequencies are obtained by using Navier technique. The numerical results obtained through the present analysis are compared with the ones available in the literature, and a parametric study is carried out to investigate the influence of the varying porosity distributions on the vibration response of FGM plates resting on elastic foundation. [ABSTRACT FROM AUTHOR]

Boñar Formation (Upper Cretaceous) is a mainly carbonate succession, which outcrops in the North of Duero Basin (Spain). According to the existing data, the Dolomitic Member of this formation appears to be the most suitable for geological storage of CO2. The main objective of this study is to find evidence to support, clarify and specify –at an initial level– the potential of the Dolomitic Member of the Boñar Formation as a geological reservoir. The study covers density, porosity and permeability tests on samples obtained from the outcrop of the succession near the village of Boñar (León). According to the analysis and interpretation of the mentioned petrophysical properties, the porosity of the Dolomitic Member is within the acceptable range for CO2 geological storage, but the permeability values are far too low. This minimizes the possibilities of the Dolomitic Member –and probably of the whole Boñar Formation– to become an appropriate CO2 reservoir.

This work aims to valorize a mineral and natural resources such as the Limestone Fillers (F-Lime) and the Natural Pozzolan (PN) by incorporating them into the formulation matrix of cement or concrete. In order to minimize the CO2 emissions into the atmosphere, to reduce the energy and raw materials consumption and as well as, to improve the physical and mechanical properties in fresh cement paste and of mortar or concrete in the hardened state. In this present manuscript, we substituted the clinker by the combination between the F-Lime and NP at 40% by weight of cement with steps of 5% with the admixture of superplasticizers. The influences of the incorporation of these additions on physical and mechanical properties of mortar or concrete in the fresh cement paste and hardened state were evaluated. The obtained results by different formulations elaborated to show that the replacement a part of clinker by the mixing of F-Lime and PN has produced a new hydraulic binder eco-friendly and durable with improved physicochemical, physical and mechanical properties. These results show that we have succeeded to manufacture, characteristic and formulated of new ecofriendly hydraulic binder and sustainable with improved physical, chemical, and mechanical properties while minimizing greenhouse gas emissions on one hand and the reducing the energy raw materials consumption on the other hand.

This paper presents a method for determining the interfacial stresses in an adhesive joint between a strengthening plate and a functionally graded beam. The beam is assumed to be isotropic with a constant poisson’s ratio. The present method is based on the deformation compatibility principle taking into account the neutral axis position of the FG beam. A power law for the distribution of the mechanical characteristic with a uniform and non-uniform porosity distribution is presented. A parametric study is presented to show the effect of some parameters on the distribution of stresses in the adhesive joint between the plat and the beam.

More than 70 rock samples from so-called sweet spots, i.e. the Ordovician Sa Formation and Silurian Ja Member of Pa Formation from the Baltic Basin (North Poland) were examined in the laboratory to determine bulk and grain density, total and effective/dynamic porosity, absolute permeability, pore diameters size, total surface area, and natural radioactivity. Results of the pyrolysis, i.e., TOC (Total Organic Carbon) together with S1 and S2 – parameters used to determine the hydrocarbon generation potential of rocks, were also considered. Elemental composition from chemical analyses and mineral composition from XRD measurements were also included. SCAL analysis, NMR experiments, Pressure Decay Permeability measurements together with water immersion porosimetry and adsorption/ desorption of nitrogen vapors method were carried out along with the comprehensive interpretation of the outcomes. Simple and multiple linear statistical regressions were used to recognize mutual relationships between parameters. Observed correlations and in some cases big dispersion of data and discrepancies in the property values obtained from different methods were the basis for building shale gas rock model for well logging interpretation. The model was verified by the result of the Monte Carlo modelling of spectral neutron-gamma log response in comparison with GEM log results.

Submitted article focuses on possibilities of increasing internal quality of flap casting of turbine engine produced by investment casting technology. Material porosity will be eliminated by altering the gate system. ProCast software has been used to evaluate and analyse the design of the flap. The aim of the research was to evaluate the porosity of the cast after its solidification, the flow velocity of the melted material and visualise the turbulence of the flow during casting. Main aim will be to observe and analyse velocity, flow, turbulences, solidification and internal porosity for nickel based alloy.

Solid Oxide Fuel Cell (SOFC) is an electrochemical equipment that converts gas into electricity directly. The waste products resulting from SOFC are water vapor and heat when using hydrogen gas. The electrode of the SOFC is the anode, electrolyte and cathode. The performance of SOFC is influenced porosity of the electrode. This study explained the relationship between porosity of the anode and temperature distribution using computational fluid dynamics modeling approach (CFD). In this study, CFD modeling was done by using Fluent software. The geometry model of computational modeling is a planar radial-type SOFC. The assumptions of some boundary conditions used from the study of literature and the object of study. The standard deviation and the different of temperature of the anode-electrolyte surface used to analyse the result. Non-homogenous temperature distribution rise if the anode porosity and gas flow rate is increasing. This indicates the gradient of temperature is bigger in the higher porosity, which may cause thermal stress and degrades the materials of electrode.

Self-compacting concretes (SCC), are hyper-fluid concretes, placed without vibration and are considered as one of the most important innovations of the last decade in construction. SCCs offer many advantages, due to their exceptional characteristics of flow and filling of formwork. Their compositions require a large quantity of fines in order to limit bleeding and segregation. Hence, the use of crushed sand (SC), rich in limestone fines (CF) in the manufacture of self-placing concretes (SCC), can be considered as an alternative source of fillers. These sands reduce the cost of SCC by reducing the high demand for fillers on the one hand and on the other hand, obtaining SCC with good physical and mechanical properties. The main purpose of this paper is to examine the effect of different percentages (0, 5, 10, 15, and 20%) of (CF) in crushed sand on SCC performance. The evolution of the compressive strength, the porosity accessible to water and the migration coefficient of the chloride ions were evaluated. The Okamura method was used for the formulation of all SCC mixtures. Sand/mortar (S/M), water/cement (W / C) ratios and superplasticizer content were kept constant. The results show that (CF) reduce the compressive strength but contribute to the reduction of porosity and migration of chloride ions.

Cathodoluminescence analyses on samples from Middle Jurassic oolitic limestones allow us to reconstruct the diagenetic history of these oil and gas reservoirs: a succession of events starting with the early, synsedimentary phases of marine cementation and ending with the addition of hydrocarbons to the reservoir. Constraints on the timing of events are derived from their calibration with the chronology of the well-known regional tectonic calendar. Fracturing, due first to the post-Pyrenean extension and then to the Alpine compression, led respectively in Oligocene times to a recharge of the aquifer and a correlative change in cementation, and in Miocene times to the addition of hydrocarbons into the same flow units, this last event blocking diagenesis, at least in the zone above the oil-water contact. Distributions of cements and residual porosity within sedimentary units without stratigraphic significance, called here "pseudo-parasequences", were for the most part inherited from the original depositional facies.