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Synthesis and properties of AxV2Al20 (A = Th, U, Np, Pu) ternary actinide aluminides
PublikacjaPolycrystalline samples of AxV2Al20 (A = Ce, Th, U, Np, Pu; 0.7 ≤ x ≤ 1.0) actinide intermetallics were synthesized using the arc-melting method. Crystal structure studies were performed by means of powder x-ray diffraction and the Rietveld refinement method. All studied compounds crystallize in the CeCr2Al20-type structure (space group Fd-3m, no. 227) with the actinoid and Ce atom located in the oversized icosahedral cage formed...
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Materials Design for the Titanium Scaffold Based Implant
PublikacjaThe main objective of here presented research is a design the scaffold/porous titanium(Ti) alloy based composite material demonstrating better biocompatibility, longer lifetime andbioactivity behaviour for load-bearing implants. The development of such material is proposed bymaking a number of consecutive tasks. Modelling the mechanical, biomechanical and biologicalbehavior of porous titanium structure and an elaboration of results...
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Materials Design for the Titanium Scaffold Based Implant
PublikacjaThe main objective of here presented research is a design the scaffold/porous titanium(Ti) alloy based composite material demonstrating better biocompatibility, longer lifetime andbioactivity behaviour for load-bearing implants. The development of such material is proposed bymaking a number of consecutive tasks. Modelling the mechanical, biomechanical and biologicalbehavior of porous titanium structure and an elaboration of results...
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Tetrahydroquinolinone derivatives exert antiproliferative effect on lung cancer cells through apoptosis induction
PublikacjaThe anticancer properties of quinolones is a topic of interest among researchers in the scientific world. Because these compounds do not cause side effects, unlike the commonly used cytostatics, they are considered a promising source of new anticancer drugs. In this work, we designed a brief synthetic pathway and obtained a series of novel 8-phenyltetrahydroquinolinone derivatives functionalized with benzyl-type moieties at position...
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Phosphinophosphoranes: Mixed-Valent Phosphorus Compounds with Ambiphilic Properties
PublikacjaHerein, we present a simple synthesis of mixed-valent phosphinophosphoranes bearing three- and five-coordinate phosphorus centers. Compounds with phosphorus–phosphorus bonds were synthesized via a reaction of lithium phosphides RR′PLi with cat2PCl (cat = catecholate), whereas derivatives with methylene-linked phosphorus centers were obtained via a reaction of phosphanylmethanides RR′CH2Li with cat2PCl. The presence of accessible...
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A Proposed Machine Learning Model for Forecasting Impact of Traffic-Induced Vibrations on Buildings
PublikacjaTraffic-induced vibrations may cause various damages to buildings located near the road, including cracking of plaster, cracks in load-bearing elements or even collapse of the whole structure. Measurements of vibrations of real buildings are costly and laborious. Therefore the aim of the research is to propose the original numerical algorithm which allows us to predict, with high probability, the nega-tive dynamic impact of traffic-induced...
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Tacit Knowledge Sharing and Project Performance. Does the Knowledge Workers' Personal Branding Matter?
PublikacjaTacit knowledge sharing is the real challenge for knowledge management today. Network economy has completely changed the role of knowledge workers who now become independent tacit knowledge producers. Bearing this fact in mind, the author studied how tacit knowledge sharing affects the process of building a personal brand and project performance. For this purpose, the authors conducted a study among Polish professionals with different...
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Assessment and design of greener deep eutectic solvents – A multicriteria decision analysis
PublikacjaDeep eutectic solvents (DES) are often considered as green solvents because of their properties, such as negligible vapor pressure, biodegradability, low toxicity or natural origin of their components. Due to the fact that DES are cheaper than ionic liquids, they have gained many applications in a short period of time. However, claims about their greenness sometimes seem to be exaggerated. Especially, bearing in mind lots of data...
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Tacit Knowledge Sharing and Creativity. How to Derive Innovation from Project Teams?
PublikacjaModern companies are increasingly likely to work in a project management environment, which ensures their success in the implementation of innovation. The aim of the study is to prove that tacit knowledge is a mediator for creativity and project performance. Creativity as one of the crucial sources of innovation is stimulated by tacit knowledge. Bearing this fact in mind, the authors studied relations between tacit knowledge, creativity...
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Operational problems of large power diesel engines combusting biofuels, considered togetherwith assessment of their operation
PublikacjaWithin this article the issue of large power self ignition engines fed with biofuels has been undertaken. The analysis focused mainly on operation problems. There has been noticed some advantages and difficulties associated with the biofuel application to self ignition engines. The research problem has been characterised and the research purposes have been proposed enabling the most profitable formation of energetic features of...
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Selected elements of the methodology and method of designing amphibious flood rescue vehicles
PublikacjaThe methodology of designing amphibious flood rescue vehicles at the preliminary stage of the design process has been presented. The study has been focused on the properties of such vehicles when afloat, with their on-land behaviour and performance characteristics having been left aside. In the study, a general assumption has been made that the amphibious flood rescue vehicles should be designed as, above all, watercraft that additionally...
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Groundwater Quality in the Gdansk Aquifer System
PublikacjaThe Gdańsk hydrogeological system consists of three main aquifers: Cretaceous, Paleogene-Neogene and Pleistocene. Chemical composition of groundwater varies between water-bearing beds, although water from Pleistocene and Paleogene-Neogene aquifers shows much similarities. The dominant hydrochemical groundwater types is HCO3-Ca. This type is characteristic for Pleistocene deposits in the Kashubian Lake District where natural chemical...
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Novel condition monitoring of induction motor bearings via motor current signature analysis
PublikacjaThe paper authors are researching the assessment of bearing conditions in induction motors. The methods developed by the authors are based on measurements and analysis of the motor supply current, which is particularly attractive in the absence of access to the engine. The article provides an overview of selected methods of induction motor bearings diagnostic based on Motor Current Signature Analysis (MCSA). However, there is no...
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Effects of electrophoretic deposition times and nanotubular oxide surfaces on properties of the nanohydroxyapatite/nanocopper coating on the Ti13Zr13Nb alloy
PublikacjaLoad-bearing implants are developed with a particular emphasis placed on an application of ceramic hydroxyapatite coatings in order, to enhance the bioactivity of titanium implants and to shorten the healing time. Therefore, thin, fully crystalline coatings that are, highly adhesive, hydrophilic and demonstrating antibacterial properties are ly looked for. The aim of this research was to develop and characterize the properties...
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Load-carrying capacity of axially loaded concrete-filled steel tubular columns made of thin tubes
PublikacjaAn experimental investigation was conducted on 30 CFST columns. An influence of the following factors on load-carrying capacity of the investigated columns was analyzed: the column slenderness (l1 = 42, l2 = 27 and l3 = 15), the tube thickness (the reinforcement ratio was equal to 4% or 6%), the way of applying the load to CFST columns (through the concrete core or through the entire cross-section), the bond strength between a...
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Application of twin-plane ECT sensor for identification of the internal imperfections inside concrete beams
PublikacjaThe main purpose of this paper is to investigate application of special construction of Electrical Capacitance Tomography (ECT) sensor to concrete beams internal homogeneity tests. Identification of internal imperfection inside the concrete beams is one of the main problems related to analysis of the construction structure bearing capacity. Therefore, this paper shows attempts to study the measurement prospects for this non-invasive,...
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Results of the “DPDT-Auger” Research Project on Screw Displacement Piles
PublikacjaThe main objective of the “DPDT-Auger” research project was to test the prototype DPDT auger for forming screw displacement piles in the ground (patented in Poland in 2020). An additional aim was to develop design methods and rules for the making of such piles. The augers and piles were first tested on a model scale, and then more extensively in the real scale on experimental field plots. The results found the overall functionality...
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Synthesis and Characterization of Poly(zwitterionic) Structures for Energy Conversion and Storage
PublikacjaZwitterions are unique class of molecules that possess two functional groups bearing electric charges, one positive and second negative. This setup results in peculiar properties such as high water retention and anti-fouling capability. Therefore, zwitterionic coatings and gels are commonly applied in e.g. biosensing and bioelectronic devices. Despite those applications, there are other perspectives for zwitterionic materials....
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Digital Gaps and Economic Inequalities in MENA Countries: An Empirical Investigation
PublikacjaThis research contributes to the present state of the art by examining changes in cross-country inequalities in digital technologies deployment and economic performance. Our empirical target builds on the hypothesis that rapid global diffusion of digital technologies unequivocally leads to gradual eradication of cross-country digital gaps and cross-country inequalities in terms of deployment of ICT; the technology convergence occurs....
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Yerba Mate - A Long but Current History
PublikacjaBearing in mind the growing interest in Yerba Mate, a comprehensive study has been prepared containing the most important aspects and possibilities of its use. The introduction of the work contains the species characteristics of Yerba Mate, as well as information about the origin and places of cultivation. The next part focuses on the analysis of the composition, pointing to purine alkaloids, polyphenols, saponins, and minerals...
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Supply current signal and artificial neural networks in the induction motor bearings diagnostics
PublikacjaThis paper contains research results of the diagnostics of induction motor bearings based on measurement of the supply current with usage of artificial neural networks. Bearing failure amount is greater than 40% of all engine failures, which makes their damage-free operation crucial. Tests were performed on motors with intentionally made bearings defects. Chapter 2 introduces the concept of artificial neural networks. It presents...
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Palindromic carbazole derivatives: unveiling their antiproliferative effect via topoisomerase II catalytic inhibition and apoptosis induction
PublikacjaHuman DNA topoisomerases are essential for crucial cellular processes, including DNA replication, transcription, chromatin condensation, and maintenance of its structure. One of the significant strategies employed in cancer treatment involves the inhibition of a specific type of topoisomerase, known as topoisomerase II (Topo II). Carbazole derivatives, recognised for their varied biological activities, have recently become a significant...
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The influence oil additives on spread cracks in silicon nitride
PublikacjaThe paper presents an experimental study of the influence of oil additives (Cl, S, P, cerium dioxide (CeO2)) on spread cracks in silicon nitride. The additives Cl, S, P are bound in molecules in liquid form soluble in the base oil. The CeO2 is purely in powder form in suspension. The use of CeO2 powder was made based on the good results of polishing of silicon nitride. A ceramic angular contact ball bearing was modelled using a...
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Powder metallurgy of the porous Ti-13Nb-13Zr alloy of different powder grain size
PublikacjaThe objective of the present project was to determine the effects of powder granulation (fraction of grain size) for the Ti-13Nb-13Zr alloy, produced by powder metallurgy, on its porosity, grain cohesion, compressive strength, and Young`s modulus. Two powder fractions, 45–105 µm, and 106–250 µm were applied. The 50 mass pct of NH4HCO3 was added as a space holder. The specimens were in compaction stage uniaxially pressed at pressure...
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Thermal and technological aspects of double face grinding of Al2O3 ceramic materials
PublikacjaDouble face grinding with planetary kinematics is a process to manufacture workpieces with plan parallel functional surfaces, such as bearing rings or sealing shims. In order to increase the economic efficiency of this process, it has to be advanced permanently. The temperature in the contact zone of most grinding processes has a huge influence on the process efficiency and the workpiece qualities. In contrast to most grinding...
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Synthesis, Molecular Structure, Anticancer Activity, and QSAR Study of N-(aryl/heteroaryl)-4-(1H-pyrrol-1-yl)Benzenesulfonamide Derivatives
PublikacjaA series of N-(aryl/heteroaryl)-4-(1H-pyrrol-1-yl)benzenesulfonamides were synthesized from 4-amino-N-(aryl/heteroaryl)benzenesulfonamides and 2,5-dimethoxytetrahydrofuran. All the synthesized compounds were evaluated for their anticancer activity on HeLa, HCT-116, and MCF-7 human tumor cell lines. Compound 28, bearing 8-quinolinyl moiety, exhibited the most potent anticancer activity against the HCT-116, MCF-7, and HeLa cell lines,...
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Laboratory fatigue assessment of large geocomposite-reinforced double-layered asphalt concrete beams
PublikacjaGeosynthetic reinforcement of asphalt layers has been used for several decades. Evaluation of the influence of these materials on pavement fatigue life is still ongoing, especially for new types of geocomposites. This paper presents the evaluation of fatigue performance of large asphalt concrete beams reinforced with a new type of composite in which square or hexagonal polypropylene stiff monolithic paving grid with integral junctions...
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Experimental investigation of joint with positive eccentricity in CFS truss
PublikacjaDue to technological restrictions, in the case of trusses made of CFS open cross-sections, positive eccentricities in the truss joints have become very frequent. Therefore studies concerning the load-bearing capacity of truss joints with positive eccentricity were undertaken. It was assumed that the resistance of cold-formed steel (CFS) open cross-section truss joints located on compression chords and with positive eccentricity...
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Study on some of the strength properties of soft clay stabilized with plastic waste strips
PublikacjaIt is well known that if plastic wastes are not well managed, it has a negative impact on the environment as well as on human health. In this study, recycling plastic waste in form of strips for stabilizing weak subgrade soil is proposed. For this purpose, a weak clay soil sample was mixed with 0.2%, 0.3%, and 0.4% of plastic strips by weight of soil, and the experimental results were compared to the control soil sample with 0%...
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Laboratory fatigue assessment of large geocomposite-reinforced double-layered asphalt concrete beams
PublikacjaGeosynthetic reinforcement of asphalt layers has been used for several decades. Evaluation of the influence of these materials on pavement fatigue life is still ongoing, especially for new types of geocomposites. This paper presents the evaluation of fatigue performance of large asphalt concrete beams reinforced with a new type of composite in which square or hexagonal polypropylene stiff monolithic paving grid with integral junctions...
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The Idea of Using Adhesive Bonds in Shaping of Cold-formed Thin-walled Beam-columns
PublikacjaThe chapter concerns the idea of using adhesive bonds in the shaping of cold-formed thin-walled beam-columns. The idea of adhesive-bonded connections is not new but is unlikely to have been used in the design and shaping of thin-walled beam-columns in civil engineering up to date. Metal bar structures, including (due to economic reasons) thin-walled structures, are the most common and effective means to build engineering superstructures/loadbearing...
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Axial-Flux Permanent-Magnet Dual-Rotor Generator for a Counter-Rotating Wind Turbine
PublikacjaCoaxial counter-rotating propellers have been widely applied in ships and helicopters for improving the propulsion efficiency and offsetting system reactive torques. Lately, the counter-rotating concept has been introduced into the wind turbine design. Distributed wind power generation systems often require a novel approach in generator design. In this paper, prototype development of axial-flux generator with a counter-rotating...
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The Experimental Determination of Bearings Dynamic Coefficients in a Wide Range of Rotational Speeds, Taking into Account the Resonance and Hydrodynamic Instability
PublikacjaMethods for the experimental determination of dynamic coefficients are commonly used for the analysis of various types of bearings, including hydrodynamic, aerodynamic and foil bearings. There are currently several algorithms that allow estimating bearing dynamic coefficients. Such algorithms usually use various excitation techniques applied to rotor–bearings systems. So far only a small number of scientific publications show how...
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Reactivity of Diimido Complexes of Molybdenum and Tungsten towards Lithium Derivatives of Diphosphanes and Triphosphanes
PublikacjaThe reaction of R2P–P(SiMe3)Li (R = tBu, iPr) with the diimido molybdenum complex [(ArN)2MoCl2·dme] (Ar = 2,6-iPr2C6H3; dme = 1,2-dimethoxyethane) yielded the side-oncoordinated phosphanylphosphinidene anionic complexes [(2,6-iPr2C6H3N)2Mo(Cl)(η2-P=PR2)]– (7Mo, 8Mo). The thermal decomposition of [(2,6-iPr2C6H3N)2M(Cl)(η2-P=PR2)]–[M = Mo (7Mo), W (8W)] to [(2,6-iPr2C6H3N)2M(Cl)(1,2-η-tBu2P=P–PtBu2)] [M = Mo (3Mo), W (3W)] was investigated...
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Mechanical Behavior of Plastic Strips-Reinforced Expansive Soils Stabilized with Waste Marble Dust
PublikacjaExpansive soil needs to undergo treatment to be used as safe foundation soil for roads and buildings. From an environmental conservation and economical point of view, the usage of agricultural and industrial wastes is the best option. In this study, the effects of utilizing plastic waste and marble waste dust on the engineering properties of expansive soils were examined. Various laboratory tests were carried out on sampled expansive...
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The influence of magnetic particle incorporation on bisphenol A removal by β-cyclodextrin-derived sorbent
PublikacjaA novel, biomass-derived hybrid sorbent Ban-CD-EPI-Fe was successfully synthesized in a coprecipitation method, in which β-cyclodextrin copolymerized with banana peel extract and epichlorohydrin was grafted onto an iron oxide surface. The composition, presence of functional groups, morphology, thermal stability, and magnetic properties of the obtained material were characterized by Powder X-Ray Diffraction (XRD), X-Ray Photoelectron...
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Multifaceted Analyses of Four Different Prototype Lightweight Photovoltaic Modules of Novel Structure
PublikacjaDynamic growth of photovoltaic capacity in Poland encourages many entities to invest in photovoltaic systems. However, in the case of buildings with low roof-bearing capacity it can be problematic or even impossible to mount conventional PV modules due to their relatively high weight. Hence, the use of lightweight PV modules is a potential solution. In this paper four different prototype silicon lightweight modules of novel structure...
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A High-Arctic flow-through lake system hydrochemical changes: Revvatnet, southwestern Svalbard (years 2010–2018)
PublikacjaLake ecosystems are strongly coupled to features of their surrounding landscapes such as geomorphology, lithology, vegetation and hydrological characteristics. In the 2010–2018 summer seasons, we investigated an Arctic flow-through lake system Revvatnet, located in the vicinity of the coastal zone of Hornsund fjord in Svalbard, characterising its hydrological properties and the chemical composition of its waters. The lake system...
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The Idea of Using Bayesian Networks in Forecasting Impact of Traffic-Induced Vibrations Transmitted through the Ground on Residential Buildings
PublikacjaTraffic–induced vibrations may constitute a considerable load to buildings. In this paper, vibrations transmitted through the ground caused by wheeled vehicles are considered. This phenomenon may cause cracking of plaster, cracks in load-bearing elements or even, in extreme cases, collapse of the whole structure. Measurements of vibrations of real structures are costly and laborious. Therefore, the aim of the present paper is to...
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Syntheses and Structures of Transition Metal Complexes with Phosphanylphosphinidene Chalcogenide Ligands
PublikacjaThe reactivity of the phosphanylphosphinidene complex [(DippN)2W(Cl)(η2-P-PtBu2)]− (1) toward chalcogens (Ch = Se, S) was studied. Reactions of stoichiometric amounts of 1 with chalcogens in DME yielded monomeric tungsten complexes with phosphanylphosphinidene chalcogenide ligands of the formula tBu2P−P−Ch (Ch = Se (in 2) and S (in 5)), which can be regarded as products of the addition of a chalcogen atom to a P=W bond in starting...
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Mechanical Behavior of Plastic Strips-Reinforced Expansive Soils Stabilized with Waste Marble Dust
PublikacjaExpansive soil needs to undergo treatment to be used as safe foundation soil for roads and buildings. From environmental conservation and economical point of view, the usage of agricultural and industrial wastes is the best option. In this study, the effects of utilizing plastic waste and marble waste dust on the engineering properties of expansive soils were examined. Various laboratory tests were carried out on sampled expansive...
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(R,R)-1-Acetyl-1'-(2,4,6-trinitrophenyl)-2,2'-bipyrrolidine
Publikacja(R,R)-1-Acetyl-1'-(2,4,6-trinitrophenyl)-2,2'-bipyrrolidine has been synthesized and its rentgenostructure has been determined. The structure of the title molecule, C16H19N5O7, is mainly determined by the steric effect of a bulky 2,4,6-trinitrophenyl group attached to the N atom of a pyrrolidine ring. Both pyrrolidine rings adopt an envelope conformation, with one of the methylene C atoms as the flap in each case, and the N-C-C-N...
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Determination of long-chain aldehydes using a novel quartz crystal microbalance sensor based on a biomimetic peptide
PublikacjaThere is an increasingly popular trend aimed at improvement of fundamental metrological parameters of sensors via implementation of materials mimicking biological olfactory systems. This study presents investigation on usefulness of the peptide mimicking HarmOBP7 region as a receptor element of the piezoelectric sensor for selective analysis of long-chain aldehydes. Identification of odorant binding proteins creates new possibilities...
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Effects of full displacement pile installation on the stress and deformation state of surrounding soil: review
PublikacjaSeveral field and model tests have been conducted to investigate the impact of pile installation on bearing capacity. However, little is known about how piles behave during installation, how they interact with the surrounding soil, and how this affects sandy soil properties. This review paper investigates the effect of pile driving on surrounding sandy soil as it compacts sandy soil near to the pile. For this purpose, various related...
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Modeling the application of steel slag in stabilizing expansive soil
PublikacjaThe objective of this study was to evaluate the suitability of steel slag as an additive to the engineering properties of weak clay soil. Different geotechnical laboratory tests were conducted on both stabilized and natural soils. Steel slag (SS) was added at a rate of 0, 5, 10, 15, 20, and 25% to the soil. Specific gravity, grain size analysis, Atterberg limit test, compaction test, free swell, California bearing ratio (CBR),...
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Dependence between Ionic Liquid Structure and Mechanism of Visible-Light-Induced Activity of TiO2 Obtained by Ionic-Liquid-Assisted Solvothermal Synthesis
PublikacjaBecause of the tremendous structural diversityof ionic liquids (ILs), simple transfer of observations performed for one IL used for IL-TiO2 preparation on different samples is not possible. Therefore, four ionic liquids, all containing distinct nitrogen-bearing organic cations (pyridinium, pyrrolidinium, ammonium, imidazolium), were used for the first time for the preparation of IL-TiO2 composites. The role of the individual IL...
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Analysis of the Heating Process of Hydraulic Motors during Start-Up in Thermal Shock Conditions
PublikacjaConditions that prevail during harsh winters and hot summers pose a serious challenge for machine designers building devices suitable for operation in extreme weather. It is essential for the designers and the users to define the principles and conditions for the safe operation of machines and devices with hydraulic drive in low ambient temperatures. Bearing in mind the above, the author tested the hydraulic motors in thermal shock...
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Automatic Identification System (AIS) Dynamic Data Integrity Monitoring and Trajectory Tracking Based on the Simultaneous Localization and Mapping (SLAM) Process Model
PublikacjaTo enhance the safety of marine navigation, one needs to consider the involvement of the automatic identification system (AIS), an existing system designed for ship-to-ship and shipto- shore communication. Previous research on the quality of AIS parameters revealed problems that the system experiences with sensor data exchange. In coastal areas, littoral AIS does not meet the expectations of operational continuity and system availability,...
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Green products from herbal medicine wastes by subcritical water treatment
PublikacjaHerbal medicine wastes (HMWs) are byproducts of medicine factories, which are mainly landfilled for their environmental problems. Only bearing in mind the contamination and concerns caused by the COVID-19 pandemic and environmental emissions, the worth of herbal medicine wastes management and conversion to green products can be understood. In this work, subcritical water treatment was carried out batch-wise in a stainless tube...
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How thermal stability of ionic liquids leads to more efficient TiO2-based nanophotocatalysts: Theoretical and experimental studies
PublikacjaIonic liquids (ILs) containing distinct nitrogen-bearing organic cations (pyridinium, pyrrolidinium, imidazolium, ammonium, morpholinium) were first used for the preparation of 23 IL-TiO2 types of composites by ionic liquid assisted solvothermal synthesis. These 23 optimal ILs structures (i.e. compounds exhibiting an optimal combination of specific properties, functionality, and safety) for synthesis and experimental validation...