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Search results for: aggregate level
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Impact performance of novel multi-layered prepacked aggregate fibrous composites under compression and bending
PublicationMulti-layered Prepacked aggregate fibrous composite (MLPAFC) is a new type of concrete, which is prepared in two subsequent stages of aggregate-fibre skeleton prepacking and cementitious grouting. In this study, ten MLPAFC mixtures were prepared in three subsequent layers incorporating different contents of four different types of steel fibres. Long and short hooked-end and crimped steel fibers were adopted with 3.0 and 1.5% dosages...
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Study of the Resistance to Influence of Aggressive Liquids on Concrete with Lightweight Aggregate
PublicationThe corrosion of the structure of concrete caused by the aggressive external environment is one of the main problems that can reduce the durability of buildings. The paper analyzes the influence of the type of component on selected properties of lightweight concrete (LWC) exposed to aggressive liquids. When lightweight concrete containing porous aggregates is used, the influence of an aggressive environment may be of particular...
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Price convergence in the European Union and in the new member states
PublicationThis paper examines price dispersion in the European Union (EU15) and in three New Member States (Poland, Hungary and the Czech Republic) between 1995 and 2006. The analysis utilizes both disaggregate and aggregate price data, including the prices of 157 products and two indices constructed using two different weighting procedures. For each category of goods the price dispersion is lower in EU15 than EU15 plus 3 NMS. Sigma convergence...
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A material model of asphalt mixtures based on Monte Carlo simulations
PublicationThe paper aims to numerically reflect mineral-asphalt mixture structure by a standard FEM software. Laboratory test results are presented due to bending tests of circular notched elements. The result scatter is relatively high. An attempt was made to form a random aggregate distribution in order to obtain various results corresponding to laboratory tests. The material structure calibration, its homogenization and finite element...
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Euro 2012 in Gdańsk, Poland. Is it worth using public funds?
PublicationThe aim of this study is to estimate the willingness - to - pay (WTP) among the community of the Pomeranian region, Poland in connection with intangible benefits and costs st emming from hosting the Euro 2012 in Gdansk. A survey conducted among 407 respondents was the source of information. The results of the study show that the average value of WTP benefit for the whole sample was 45,72 PLN2012 and WTP cost...
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Attitudes to tree removal on private property in rural and urban Polish municipalities.
Open Research DataThe urban-rural divide is an important factor known to affect public opinion on issues related to environmental protection and management. The present data set allows for a deeper understanding of this issue with respect to policies dealing with tree removal on private property in two municipalities located in southern Poland: Racibórz (an urban municipality)...
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How Chain Transfer Leads to a Uniform Polymer Particle Morphology and Prevents Reactor Fouling
PublicationABSTRACT: The effect of adding diethyl zinc as a chain transfer agent during the polymerization of propylene in heptane performed at 80 °C was studied. Although it was expected that the chain transfer would stop after precipitation of the polymer, the polymer molecular weight continued to increase throughout the whole of the polymerization. The presence of diethyl zinc had an additional effect that the polymerizations were devoid...
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Thermal stabilization and permanent deformation resistance of LWA/PCM-modified asphalt road surfaces
PublicationThis paper presents the results of attempts at reducing the problem of solar overheating of asphalt road pavement surfaces, resulting in weakening and accelerated destruction of the aforementioned structures. To protect pavement surfaces against periodic overheating, standard asphalt mixture AC 16 W 35/50, used for binder course, has been modified by replacing one of the aggregate fractions from the mineral mixture with lightweight...
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Attitudes to tree removal on private properties in two Polish cities.
Open Research DataLarge cities are increasingly faced with declining urban tree cover and related problems, such as increased urban heat islands and flash floods. Reducing these phenomena increasingly has to rely on trees located on private property. However, to effectively engage private landowners on these issues, more attention must be paid to understanding their...
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A study on microcrack monitoring in concrete: discrete element method simulations of acoustic emission for non-destructive diagnostics
PublicationThe research is focused on the monitoring of fracture evolution in concrete beams under three-point bending using the acoustic emission technique and the discrete element method. The main objective of the study was to numerically and experimentally investigate the mechanism behind the generation of elastic waves during acoustic emission events and their interaction with micro- and macro-cracking in concrete beams under monotonic...
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Open Innovation Competence for a Future-Proof Workforce: A Comparative Study from Four European Universities
PublicationDigital transformation is a key driving force of open innovation to capture and transfer knowledge inside and outside of a company’s bounds. New challenges in organizing multiple knowledge flows imply the need for increased competences related to this paradigm of future employees. In this article, we organize and aggregate the competencies required for open innovation collaboration and develop a competence profile that organizes...
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The Method of Multi-criteria Analysis to Support the Decision on Load or Micro-generation Connection to a Low- or Medium-voltage Power Grid
PublicationThis paper presents a method that supports the decision in terms on selecting the best option of a load connection to a low- or medium-voltage power distribution grid, and of a micro-generation source connection to a low-voltage grid. The method is based on the search for the option with the lowest aggregate assessment measure, which is the weighted average of partial assessment measures determined for each of eight considered...
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Butyrylcholinesterase signal sequence self-aggregates and enhances amyloid fibril formation in vitro
PublicationAlzheimer’s disease (AD) pathogenesis has been attributed to extracellular aggregates of amyloid β (Aβ) plaques and neurofibrillary tangles in the human brain. It has been reported that butyrylcholinesterase (BChE) also accumulates in the brain Aβ plaques in AD. We have previously found that the BChE substitution in 5′UTR caused an in-frame N-terminal extension of 41 amino acids of the BChE signal peptide. The resultant variant...
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Size effect in concrete under splitting tension
PublicationThe size effect is a fundamental phenomenon in concrete materials. It denotes that both the nominal structural strength and material ductility always decrease with increasing element size under tension. In the paper splitting tensile tests on cylindrical concrete specimens with the different diameter were carried out. Two types of the loading strip (plywood board and steel cylinder) were used. The concrete strength and ductility...
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Evaluation of the potential of Microwave Plasma–Atomic Emission Spectrometry for trace elements leaching assessment from the concrete matrix with sewage sludge ash additives
PublicationThe management of ash generated during the thermal utilization of sewage sludge is a significant environmental problem requiring an effective technological solution. One alternative way to dispose of sewage sludge is to bind it in concrete as a substitute for part of the aggregate. The properties of the C-S-H phase enable effective immobilization of harmful substances that sewage sludge contains. The amount of individual compounds...
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DMSO and TMAO—Differences in Interactions in Aqueous Solutions of the K-Peptide
PublicationInteractions between a solvent and their co-solute molecules in solutions of peptides are crucial for their stability and structure. The K-peptide is a synthetic fragment of a larger hen egg white lysozyme protein that is believed to be able to aggregate into amyloid structures. In this study, a complex experimental and theoretical approach is applied to study systems comprising the peptide, water, and two co-solutes: trimethylamide...
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Low Noise Poroelastic Road Pavements Based On Bituminous Binder
PublicationTire/road noise is the dominant source of traffic noise. It depends both on the tire design and on the characteristics of road pavements as well as on the vehicles’ operating conditions. Due to the fact that conventional (pneumatic) car tires have almost reached the limits of their ability to further reduce their noisiness, it is widely believed that the additional reduction of tire noise will be possible mainly through modifications...
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Preparation of DNA films for studies under vacuum conditions
PublicationExperiments were carried out to determine the optimum conditions required for the preparation of uniform films of supercoiled plasmid DNA to be used in irradiation experiments under high vacuum conditions. Investigations reveal that significant damage to the DNA molecules occurs due to the evacuation process when films were formed from DNA samples in ultra high purity water only. A variety of bases were tested for their possible...
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Structural Assessment of Reinforced Concrete Beams Incorporating Waste Plastic Straws
PublicationThe behavior of reinforced concrete beams containing fibers made of waste plastic straws (WPSs) under the three point bending test is examined. The effect of WPS fiber addition on the compressive and split tensile strength is reported. Four concrete mixes were prepared. The control mix PS-0 had a proportion of 1 cement: 1 sand: 2 coarse aggregate and a water cement ratio of 0.4. In the other three mixes PS-0.5, PS-1.5 and PS-3,...
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Shear fracture of longitudinally reinforced concrete beams under bending using Digital Image Correlation and FE simulations with concrete micro-structure based on X-ray micro-computed tomography images
PublicationThe paper presents experimental and numerical investigations of the shear fracture in rectangular concrete beams longitudinally reinforced with steel or basalt bar under quasi-static three point bending. Shear fracture process zone formation and development on the surface of beams was investigated by Digital Image Correlation (DIC) whereas thorough analyses of 3D material micro-structure, air voids, width and curvature of shear...
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The use of a two-phase Monte Carlo material model to reflect the dispersion of asphalt concrete fracture parameters
PublicationThe work covers comprehensive laboratory tests of semi-circular bending (SCB) of asphalt concrete samples. The results of two test series, including four and 32 SCB specimens, indicate a substantial scatter of force–deflection (F-d) histories. The numerical analysis is aimed to reflect the maximum breaking load and fracture energy of the samples, pointing out their random character. The original simulation-based fictitious Monte...
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Influence of Rock Dust Additives as Fine Aggregate Replacement on Properties of Cement Composites—A Review
PublicationConcrete production consumes enormous amounts of fossil fuels, raw materials, and is energy intensive. Therefore, scientific research is being conducted worldwide regarding the possibility of using by-products in the production of concrete. The objective is not only to identify substitutes for cement clinker, but also to identify materials that can be used as aggregate in mortar and concrete productions. Among the potential alternative...
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Interfacial water controls the process of adsorption of hyperactive antifreeze proteins onto the ice surface
PublicationA mechanism of interactions between the ice-binding surface of a hyperactive antifreeze protein molecule and the ice surface is proposed, involving the influence of water present between the two surfaces on the behavior of the approaching molecule. It is demonstrated that the interfacial water, even before its full solidification, can act as a factor that pushes away or pulls nearer the protein molecule to ensure its proper positioning....
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Bees Detection on Images: Study of Different Color Models for Neural Networks
PublicationThis paper presents an approach to bee detection in video streams using a neural network classifier. We describe the motivation for our research and the methodology of data acquisition. The main contribution to this work is a comparison of different color models used as an input format for a feedforward convolutional architecture applied to bee detection. The detection process has is based on a neural binary classifier that classifies...
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Polish experience with cold in-place recycling
PublicationDeep cold in-place recycling using cement and asphalt emulsion has been used for reconstruction of existing roads since the beginning of the 1990s. This paper describes the first Polish requirements for mineral-cement-emulsion mixtures. As requirements stated for the strength of the mineral-cement-emulsion mixtures were quite high, most of the mixtures were designed using high amount of cement and aggregate added for the improvement...
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Effect of interlayer bonding quality of asphalt layers on pavement performance
PublicationThe quality of interlayer bonding at the interfaces between the asphalt layers in flexible pavements affects the overall pavement performance. Lack or partial lack of interlayer bonding between asphalt layers can cause pavement's premature failures such as rutting, slippage of the wearing course, cracking or simply a reduction in the calculated fatigue life of the pavement structure. This paper shows the case studies of investigation...
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Gender approaches to evolutionary multi-objective optimization using pre-selection of criteria
PublicationA novel idea to perform evolutionary computations (ECs) for solving highly dimensional multi-objective optimization (MOO) problems is proposed. Following the general idea of evolution, it is proposed that information about gender is used to distinguish between various groups of objectives and identify the (aggregate) nature of optimality of individuals (solutions). This identification is drawn out of the fitness of individuals...
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Are the short cationic lipopeptides bacterial membrane disruptors? Structure-Activity Relationship and molecular dynamic evaluation
PublicationShort cationic lipopeptides are amphiphilic molecules that exhibit antimicrobial activity mainly against Grampositives. These compounds bind to bacterial membranes and disrupt their integrity. Here we examine the structure-activity relation (SAR) of lysine-based lipopeptides, with a prospect to rationally design more active compounds. The presented study aims to explain how antimicrobial activity of lipopeptides is affected by...
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Further development of the poroelastic road surface within the new Polish project SEPOR
PublicationRoad surfaces have a direct impact on noise generated by rolling tyres, the main and dominant source of noise of moving vehicles. Road surface texture, porosity and stiffness/elasticity govern the pavement contribution to tyre/road noise the most. An experimental PoroElastic Road Surface (PERS) is a wearing course with a high content of interconnected voids (pores) and with an elastic behavior due to the use of small particles...
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Flexible Knowledge–Vision–Integration Platform for Personal Protective Equipment Detection and Classification Using Hierarchical Convolutional Neural Networks and Active Leaning
PublicationThis work is part of an effort to develop of a Knowledge-Vision Integration Platform for Hazard Control (KVIP-HC) in industrial workplaces, adaptable to a wide range of industrial environments. The paper focuses on hazards resulted from the non-use of personal protective equipment (PPE). The objective is to test the capability of the platform to adapt to different industrial environments by simulating the process of randomly selecting...
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Poroelastic Road Surface – a Promising Road Traffic Noise Abatement Solution
PublicationRoad surfaces have a direct impact on the generation of noise by rolling tyres, the main and dominant source of noise of moving vehicles, as well as may affect propagation of noise emitted by all noise sources of a vehicle. Thus there is no doubt that pavement should be considered as one of the major potential road traffic noise abatement measure. Low noise pavements of existing types may in new conditions provide up to 8 dB of...
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Noise measurements on low noise pavements - problems with inhomogeneity of wearing course
PublicationDuring the last several years, when performing numerous CPX noise measurements on low noise pavements,significant inhomogeneity of the wearing course was observed in numerous cases. Similar problems were almost not existing regarding to the dense pavements.In general three main reasons of inhomogeneity can be defined. The first one are imperfections in technology of production of a asphalt mix or/and errors made already during...
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Unraveling the role of boron dimers in the electrical anisotropy and superconductivity in boron-doped diamond
PublicationWe use quantum mechanics (QM) to determine the states formed by B dopants in diamond. We find that isolated B sites prefer to form BB dimers and that the dimers pair up to form tetramers (BBCBB) that prefer to aggregate parallel to the (111) surface in the <110> direction, one double layer below the H-terminated surface double layer. These tetramers lead to metallic character (Mott metal Insulator Transition) with holes in the...
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Initial Field Validation of Poroelastic Pavement Made with Crumb Rubber, Mineral Aggregate and Highly Polymer-Modified Bitumen
PublicationTire/road noise in most driving conditions dominates other sources of traffic noise. One of the most efficient ways of reducing tire/road noise is to use the so-called “low noise pavement”. According to numerous studies, at present, poroelastic road pavement that is composed of rubber and mineral aggregate and polyurethane or bituminous binder gives the best noise reduction up to 12 dB. Unfortunately, there are many problems with...
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Entrained Flow Plasma Gasification of Sewage Sludge–Proof-of-Concept and Fate of Inorganics
PublicationSewage sludge is a residue of wastewater processing that is biologically active and consists of water, organic matter, including dead and living pathogens, polycyclic aromatic hydrocarbons, and heavy metals, as well as organic and inorganic pollutants. Landfilling is on the decline, giving way to more environmentally friendly utilisation routes. This paper presents the results of a two-stage gasification–vitrification system, using...
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Cooperativity of Halogen- and Chalcogen-Bonding Interactions in the Self-Assembly of 4‑Iodoethynyl- and 4,7-Bis(iodoethynyl)benzo-2,1,3-chalcogenadiazoles: Crystal Structures, Hirshfeld Surface Analyses, and Crystal Lattice Energy Calculations
PublicationSeveral new 4-iodoethynyl- and 4,7-bis- (iodoethynyl)benzo-2,1,3-chalcogenadiazoles were prepared, and a comprehensive analysis of the most prominent secondary bonding interactions responsible for the crystal self-assembly was performed using X-ray diffraction. The presence of both the iodoethynyl and chalcogenadiazole moieties allows an evaluation of the preference of these molecules to aggregate through either chalcogen- or halogen-bonding...
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Evaluation of Asphalt Mixture Low-Temperature Performance in Bending Beam Creep Test
PublicationLow-temperature cracking is one of the most common road pavement distress types in Poland. While bitumen performance can be evaluated in detail using bending beam rheometer (BBR) or dynamic shear rheometer (DSR) tests, none of the normalized test methods gives a comprehensive representation of low-temperature performance of the asphalt mixtures. This article presents the Bending Beam Creep test performed at temperatures from −20...
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PERS - QUIET ROAD SURFACE FOR URBAN AREAS
PublicationTraffic noise is one of the most important environmental problems in densely populated urban areas. At low speeds the tyre/road interaction dominates all other sources. It is anticipated that when electric and hybrid vehicles gain dominance in city traffic, the importance of tyre/road noise will still increase as electric engines are much less noisy than combustion engines. On the other hand, electric and hybrid urban vehicles...
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Bitumen-Based Poroelastic Pavements: Successful Improvements and Remaining Issues
PublicationThis article presents the development process of designing and testing poroelastic pavement based on highly polymer-modified bitumen. Poroelastic wearing course was composed of mineral and rubber aggregate mixed with highly polymer-modified bitumen, in contrast to previous trials, during which polyurethane resins were mainly used as binder, which led to several serious technological problems concerning difficult production, insufficient...
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Simple empirical formula to estimate the main geomechanical parameters of preplaced aggregate concrete and conventional concrete
PublicationPreplaced aggregate concrete (PAC) or two-stage concrete is a specific type of concrete successfully employed in many projects including underwater concrete structures, massive concrete structures, structures made of reinforced concrete, and improvement of concrete structures. PAC is significantly different than the conventional concrete. In this type of concrete, aggregates are initially poured into the mold, the voids between...
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Towards bees detection on images: study of different color models for neural networks
PublicationThis paper presents an approach to bee detection in videostreams using a neural network classifier. We describe the motivationfor our research and the methodology of data acquisition. The maincontribution to this work is a comparison of different color models usedas an input format for a feedforward convolutional architecture appliedto bee detection. The detection process has is based on a neural...
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Identification of Substrates of Cytoplasmic Peptidyl-Prolyl Cis/Trans Isomerases and Their Collective Essentiality in Escherichia Coli
PublicationProtein folding often requires molecular chaperones and folding catalysts, such as peptidyl-prolyl cis/trans isomerases (PPIs). The Escherichia coli cytoplasm contains six well-known PPIs, although a requirement of their PPIase activity, the identity of their substrates and relative enzymatic contribution is unknown. Thus, strains lacking all periplasmic and one of the cytoplasmic PPIs were constructed. Measurement of their PPIase...
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Broken rotor symptoms in the sensorless control of induction machine
PublicationThe purpose of this paper is to investigate the need for a universal method for sensorless controlled induction motor drive diagnosis. The increasing number of sensorless control systems in industrial applications require a universal method for the drive diagnosis, which provides reliable diagnostic reasoning independent of control system structure and state variables measurement or estimation method.Simulations and experimental...
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The long-term properties of mineral-cement-emulsion mixtures
PublicationThis publication presents evaluation of long-term behavior of mineral-cement-emulsion (MCE) mixtures. MCE mixtures are among the major products of cold recycling of old asphalt pavements. They are composed by binding of the old materials reclaimed from the pavement and new mineral aggregate using two different binding agents – cement and bituminous emulsion. While bituminous emulsion dissolutes and binds materials quite fast, it...
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Social Convergence in Nordic NUTS-3 Regions
PublicationGeographical proximity, common historical roots and collaboration within the Nordic Council make the Nordic countries, often wrongly treated as monoliths. However, in reality, Nordic regions differ in terms of broadly defined social and economic development. Issues concerning the standard of living are one of the priorities of the Helsinki Treaty signed by Nordic countries. The main goal of this paper is to analyze the existence...
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Tyre/road noise reduction by a poroelastic road surface
PublicationLow noise road surfaces of existing types may in favourable cases and in new conditions provide up to 7 dB of noise reduction. For higher noise reductions, innovative solutions must be sought. Poroelastic road surfaces (PERS) may be such a solution, which currently is studied in the EU project PERSUADE. This paper presents results of trials with a PERS version prefabricated by one of the project partners. Tests were made in a laboratory...
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Advanced fatigue and rutting characterisation of Polish asphalt mixtures based on the VECD model and viscoplastic shift model
PublicationThe advanced asphalt mixture performance-related specifications (AM-PRS) recently developed in USA can allow an optimisation of the design process of asphalt pavements thanks to the possibility to fully take into account the intrinsic material properties. In this study, four typical Polish mixtures, i.e. a Stone Mastic Asphalt (SMA) for wearing course, two mixtures for binder course with neat bitumen or Polymer modified Bitumen...
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Overcoming carboxylic acid inhibition by granular consortia in high-load liquefied food waste fermentation for efficient lactate accumulation
PublicationGranular sludge, a self-aggregating spherical biofilm, possesses better stability compared to flocculent sludge under extreme conditions. This study compared the ability of anaerobic granular sludge (AnGS) and flocculent waste activated sludge (WAS) to convert food waste (FW) into highly-valuable optically active lactic acid (LA), a central and versatile intermediate platform molecule. Different loadings (30–60 g volatile suspended...
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Mechanical properties of two-stage concrete modified by silica fume
PublicationAbstract. Two-stage concretes, despite the fact that they have proven themselves in various types of construction, have not been studied to the same extent as traditional heavy concretes. Therefore, the article developed the composition of frame concrete with various additives in the composition of the cement-sand mortar. A comparison of the mechanical characteristics of the developed compositions with the addition of silica fume...
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Utilization of shale cuttings in production of lightweight aggregates
PublicationThe development of technologies for unconventional hydrocarbon exploration requires designing procedures to manage drilling waste that are consistent with the waste management hierarchy. In view of this, the possibility to apply shale drill cuttings as a prospective additive (replacing bentonite) to fly ash used for the production of lightweight aggregates (LWAs) was investigated. Moreover, a facile, waste-free method of LWAs production...