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Wyniki wyszukiwania dla: lcap
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Monitoring of single-side lap grinding with electroplated tools
PublikacjaThe results presented in the paper show that utilising microphones as audible sound sensors is a suitable approach for monitoring a single-side lap grinding process due to the low levels of noise generated by the drives of a machine tool. The results confirm that sound signal analysis is a feasible and relatively simple method to monitor a lap grinding process with the use of an audible sound sensor. Proposed method can be used...
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Lamb wave propagation in a single lap adhesive joint
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Lamb wave propagation in a single lap adhesive joint
PublikacjaThe aim of the paper is the analysis of Lamb wave propagation in adhesive joints. The research was performed on a single lap adhesive joint of two steel plates. Two types of joints, namely an intact and with defect were considered. In experimental investigations the condition assessment of the joint was performed with the use of antisymmetric Lamb waves excited by a plate piezo actuators and measured by a laser vibrometer. Numeri-cal...
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Influence on micrograins size on the distance between the workpiece and the lap.
PublikacjaNa kształtowanie powierzchni docieranej główny wpływ ma błąd kształtu zastosowanego narzędzia. Intensywność docierania zależy od wielkości zastosowanych ziaren ściernych, które również wpływają na błędy kształtu przedmiotu. W referacie przedstawiono wyniki obliczeń odległości przedmiotu od powierzchni narzędzia w funkcji wielkości ziaren ściernych.
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Diagnostics of bolted lap joint using guided wave propagation
PublikacjaThe paper presents numerical and experimental analyses of elastic waves propagation in a bolted lap joint. In experimental investigations condition assessment of the joint was performed with the use of symmetric waves excited by a piezoactuator. Numerical calculations were conducted in commercial finite element method software Abaqus. The influence of number of bolts and the value of the initial stress on recorded signals was examined....
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Damage detection in a bolted lap joint using guided waves
PublikacjaThe paper presents the experimental investigation of guided waves application to the condition assessment of prestressed bolted connections and a concept of new quantitative indicator. The main goal of the research was the analysis of the influence of the contact conditions changes to the characteristics of a propagating disturbance. The experimental tests were carried out for a single bolted lap joint. The excitation and acquisition...
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Verification of punching shear outside the shear cap by the direct method
PublikacjaThe proposition of a method to verify the punching resistance for very large supports based on the EN 1992-1-1 standard is described in this paper. The present standard guidelines for the calculation of the punching resistance for large supports are also summarised. The proposed direct method is compared with other standard methods using an example taken from design practice. This method consists of a direct check of the shear...
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Lamb wave-based monitoring of shear failure of an adhesive lap joint
PublikacjaThe paper presents a study on the elastic wave propagation in adhesive joints of steel plates subjected to tensile loading. A single lap joint was chosen for analysis because of its simplicity and plurality of applications. Experimental investigations consisted of the uniaxial extension of prepared specimens. Force and displacement values were recorded by a testing machine. Simultaneously, guided Lamb waves were excited and signals...
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New kinematic systems in single-sided lapping and their influence on lap wear
PublikacjaPrevious studies on one-sided lapping allow to state that not only parameters of lapping elements (i.e. properties of workpiece, abrasive grains and lapping plate) impact on a lapping efficiency. Influential are also kinematics and dynamics of the process. It is crucial to control an average velocity of lapping (v), a distribution of tangential acceleration (at), a nominal pressure (p), a lapping time (t) and disposal of workpiece...
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Analysis of the Environmental Impact of the Hull Construction of a Small Vessel Based on LCA
PublikacjaIn recent years, issues related to the impact of human activity on the natural environment have become pressing, and the challenge of global warming necessitates immediate action. To support environmental protection efforts, it has become imperative to adopt a broader perspective when evaluating various products and systems. A valuable tool for such assessments is a life cycle assessment (LCA), which enables a comprehensive analysis...
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Wear of electroplated diamond tools in lap-grinding of Al2O3 ceramic materials
PublikacjaCurrent development of modern products, together with ever-increasing demands for their operation and usage, necessitate the search for new processing methods. Abrasive machining is widely used in many industrial areas, especially for processing difficult-to-machine materials such as advanced ceramics. Grinding with lapping kinematics, also called lap-grinding, is still one of the innovative methods of abrasive processing being...
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Application of the Chimney Cap as a Method of Improving the Effectiveness of Natural Ventilation in Buildings
PublikacjaAdequately designed natural ventilation is the cheapest and easiest way to effectively remove indoor pollutants and keep the air inside a building fresh. A prediction of the performance and effectiveness of ventilation in order to determine the design of a ventilation system can provide real and long-term cost savings. The worst time in terms of the efficiency of natural ventilation is the spring-autumn transition period [7]. In...
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Photophysical properties and photocytotoxicity of free and liposome-entrapped diazepinoporphyrazines on LNCaP cells under normoxic and hypoxic conditions
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Density functional LCAO calculations of vibrational modes and phonon density of states in the strained single-layer phosphorene
PublikacjaThe paper presents an investigation of phosphorene under axial strain on the phonon density of states and vibrational modes. The studies were performed by means of density functional theory (DFT) within the linear combination of atomic orbitals (LCAO). The strained models were constructed using optimised supercell techniques. The vibrational mode spectra were estimated for strains applied for both the zigzag and armchair directions...
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Influence of the Shear Cap Size and Stiffness on the Distribution of Shear Forces in Flat Slabs
PublikacjaThe scope of this paper is to investigate analytically and numerically the influence of shear cap size and stiffness on the distribution of shear forces in flat slabs in a slab–column-connections-reinforced concrete structure. The effect of support (shear cap) stiffness on the calculation of the length of the shear control perimeter according to the available methods is presented. Based on the analysis, the authors indicate in...
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Assessment of the Environmental Impact of a Car Tire throughout Its Lifecycle Using the LCA Method
PublikacjaThere are numerous threats to the natural environment that pose a significant risk both to the environment and to human health, including car tires. Thus, there is a need to determine the impact of the life cycle of car tires on the environment, starting with the processes of raw materials acquisition, production, and ending with end-of-life management. Therefore, the authors of this study chose to do research on passenger car...
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The use of Preston equation to determine material removal during lap-grinding with electroplated CBN tools
PublikacjaGrinding executed in a lapping configuration is an alternative finishing process benefiting from both grinding and free-abrasive machining, while minimizing the heat effect impact. Electroplated tools can be effectively used in different abrasive processes, including high-speed grinding, however, the assessment of machining performance over time is a key factor in their correct use to achieve satisfactory technological results....
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Environmental impacts of food waste management technologies: A critical review of life cycle assessment (LCA) studies
PublikacjaFood waste is a serious global problem. Therefore, it is essential to reduce food waste and adopt recycling strategies to minimize its environmental impacts. However, conventional waste disposal methods emit harmful gases such as dioxin, CH4, N2O, and NH3, which contaminate the air and water resources. This work reviews the environmental consequences of food waste based on lifecycle assessment (LCA) techniques using methods such...
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Influence of Ultrasound on the Characteristics of CaP Coatings Generated Via the Micro-arc Oxidation Process in Relation to Biomedical Engineering
PublikacjaOver the past decade, bone tissue engineering has been at the core of attention because of an increasing number of implant surgeries. The purpose of this study was to obtain coatings on titanium (Ti) implants with improved properties in terms of biomedical applications and to investigate the effect of ultrasound (US) on these properties during the micro-arc oxidation (MAO) process. The influence of various process parameters, such...
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Shear Cap Size Selection Method Based on Parametric Analysis of ACI-318 Code and Eurocode 2 Standard
PublikacjaThe scope of the paper is to propose a method for determining the size of shear caps in a slab–column-connections-reinforced concrete structure. Usually, shear heads are used to enhance slab–column connection, especially when the transverse reinforcement does not give the required punching shear load capacity. The dimensions of the shear head should provide the punching shear resistance of the connection inside and outside the...
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Ion Chromatography in Environmental Analysis of Selected Organic Acids
PublikacjaLow molecular mass carboxylic acids (LCAs) occur in many environmental compartments dueto natural processes and human activity. When volatile and nonvolatile acids are to be monitored then liquidchromatography, including ion chromatography seems a method of choice. At high pH the acids are inionized form and can be separated as carboxylats by means of anion exchange chromatography. LCAs canalso be separated at low pH by ion exclusion...
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Determination of Selected Organic Acids in Animal Farm Water Samples by Ion Chromatography
PublikacjaLow molecular mass carboxylic acids (LCAs) occur in many environmental compartments due to natural processes and human activity. They are an important group of organic pollutants of waste water that mainly includes, volatile fatty acids, and also dicarboxylic, aromatic, hydroxy- and ketoacids. LCAs are present in the environment at concentrations between 1 to 5000 ppm and different methods have been reported for their determination...
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The idea of a robotic single-sided lapping system
PublikacjaThis paper reviews the idea of a robotic lapping system. Robot’s assistance automates the lap-ping process and supports the development of a flexible lapping system. However, the main aim behind the idea of a robotic lapping system is to provide improved means for controlling the posi-tion of conditioning rings on a lapping plate. Due to the kinematics of lapping process, the profile wear of the tool is not constant along the radius....
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Wpływ kierunku rozchodzenia się fali detonacyjnej oraz współczynnika asymetrii na rozkład prędkości odkształceń w kotlinie walcowniczej podczas asymetrycznego walcowania pasma Al-Cu. The influences of the direction of explosion wave and asymetrical coefficient at the distribution of strain rate in the roll cap of bimetallic plate Al-Cu of rolling process.
PublikacjaPrzedstawiono symulacje komputerowe walcowania blach Al-Cu łączonych wybuchowo. Symulacje przeprowadzono dla procesu walcowania w walcarce o średnicy walców D=150 mm z indywidualnym napędem walców roboczych. W ramach badań numerycznych określony został wpływ kierunku rozchodzenia się fali detonacyjnej na rozkład prędkości odkształcenia w kotlinie walcowniczej asymetrycznie walcowanej blachy bimetalowej Al-Cu.
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Shaping of the workpiece surface in single-disc lapping
PublikacjaShape errors of the tool exert a dominant influence on the shape accuracy of the workpiece. The correlation between flatness errors of the lap and flatness errors of the workpieces was checked experimentally and determined analytically. Computer model of the workpiece shaping by lapping was developed. Evaluation method of the workpiece orientation as well as some simulation results for a lap with shape errors of convexity and cincavity...
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Ocena cyklu życia - wieloaspektowa analiza oddziaływania produktu na środowisko
PublikacjaPrzedstawiono zasady oceny wpływu na środowisko techniką LCA zgodnie z normami Międzynarodowej Organizacji Standaryzacji. Technika LCA jest ekologicznym wskaźnikiem stanowiącym podstawę dokonania wyboru w kwestiach środowiskowych towarzyszących procesom produkcyjnym i usługowym, lub innej działalności człowieka. Zaletą tej techniki jest porównywanie wielkości oddziaływania na środowisko przez dwa lub większą liczbę produktów, różne...
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Pre-clinical evaluation of 1-nitroacridine derived chemotherapeutic agent that has preferential cytotoxic activity towards prostate cancer
PublikacjaPraca zawiera wyniki badań przedklinicznych pochodnej 1-nitroakrydyny C-1748 wobec komórek ludzkiego raka prostaty CaP in vitro, jak i przeszczepialnego na zwierzęta. W oparciu o fosforylację histonu H2AX jako markera podwójnych cięć DNA wykazano, że C-1748 jest bardziej aktywny w komórkach CaP niż HL60. Zidentyfikowano poza tym receptor androgenny (AR) jako cel molekularny badanego związku. W doświadczeniach na zwierzętach stwierdzono...
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Wzory kreatywności. Koncepcja modelu prawdopodobieństwa działania kreatywnego jako narzędzie badania procesu twórczego w środowisku miejskim
PublikacjaWspółczesne koncepcje kształtowania miast, takie jak zrównoważony rozwój, miasto odporne, inteligentne miasto, miasto kreatywne, tworzą obecnie ramy urbanistyki o charakterze jednej uogólnionej idei kształtującej środowisko społeczno-materialne. Kontekstualne ujęcie badań kreatywności opisuje zależności między środowiskiem miejskim a twórczością w mieście kreatywnym. Ujęcie procesualne kreatywności stanowi hic et nunc urbanizmu,...
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Analiza cyklu życia
PublikacjaAnaliza cyklu życia (LCA, ang. Life Cycle Analysis) z założenia obejmuje podejście „od kołyski aż po grób” w ocenie procesów przemysłowych i produktów. Ta wizja zaczyna się już w momencie wydobycia surowców pierwotnych w celu przetworzenia i wytworzenia produktu, a kończy, gdy wszystkie materiały zostają poddane utylizacji, recyklingowi lub składowaniu. LCA ocenia wszystkie etapy życia produktu z założeniem, że są od siebie współzależne,...
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The Life Cycle Assessment and Life Cycle Cost in public works contracts
PublikacjaAn important goal, implemented by EU countries under the Europe 2020 strategy, is sustainable development, which includes supporting economy that effectively uses natural and environmentally friendly resources. Solutions in this area are also promoted in tender proceedings in the area of public procurement. The LCA (Life Cycle Assessment) and LCC (Life Cycle Cost) analysis are indicated as the basis for decision-making by awarding...
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Manufacturing and Recycling Impact on Environmental Life Cycle Assessment of Innovative Wind Power Plant Part 1/2
PublikacjaWind power plants are considered as ecologically-clean source of energy. However, manufacturing processes cannot be treated that way. Manufacturing processes consume huge amount of electrical and thermal energy and significant amount of materials, e.g. steel, polymers, oils and lubricants. All of the above could be potentially harmful for environment. There are not many works and publications regarding life-cycle analysis of wind...
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Administrowanie systemami internetowymi
PublikacjaPrzedstawiono problematykę administrowania systemami internetowymi. Omówiono zasady konfguracji połączeń, integracji oraz konfguracji serwisów internetowych. Ponadto praca przedstawia zasady uwierzy-telniania użytkowników w rozproszonym systemach z wykorzystaniem mechanizmów usług katalogowych takich jak LDAP. Uwzględniono również problematykę bezpieczeństwa systemów internetowych ze szczególnym zwróceniem uwagi na najczęstsze...
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Analiza porównawcza kosztów środowiskowych budowy i eksploatacji drogi ekspresowej w technologii asfaltowej i betonowej, CZĘŚĆ 1
PublikacjaW artykule przedstawiono opis analizy porównawczej kosztów środowiskowych budowy i eksploatacji drogi ekspresowej w technologii asfaltowej i betonowej. Do przeprowadzenia badania wykorzystano analizę LCA (ang. Life Cycle Assessment). Jako założenia przyjęto warianty konstrukcji nawierzchni opracowane dla planowanej drogi ekspresowej S6 na odcinku Lębork (wraz z obwodnicą Lęborka) –obwodnica Trójmiasta, a także trzy scenariusze...
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Strontium-based nanosized phosphates as anticorrosive fi llers of epoxy and polyurethane coating compositions
PublikacjaAnticorrosive epoxy and polyurethane coatings were compounded using zinc-free nanosized phosphates of strontium (SP) or strontium and aluminum (SAP). For comparison, a nanosized calcium aluminum ammonium phosphate (CAP) and a microsized zinc phosphate (ZP) were tested. Results of salts spray and cyclic corrosion tests revealed better anticorrosive properties of the SAP-based coatings...
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Wpływ produkcji butelek z tworzyw sztucznych na środowisko naturalne. Cz. I. Zastosowanie metody oceny ReCiPe 2016 w celu identyfikacji problemów środowiskowych
PublikacjaDokonano oceny wpływu opakowań na środowisko naturalne. Głównym celem było przeprowadzenie analizy cyklu życia (LCA) butelki do napojów wykonanej z poli(tereftalanu etylenu) (PET). Za jednostkę funkcjonalną przyjęto łącznie 1000 szt. butelek PET o pojemności 1 L. Granica przyjętego systemu obejmowała kroki od momentu dostarczenia preform do zakładu produkcyjnego aż do ich prawidłowego ukształtowania w procesie produkcyjnym. Z systemu...
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A universal method for the identification of genes encoding amatoxins and phallotoxins in poisonous mushrooms
PublikacjaABSTRACT Background. As the currently known diagnostic DNA targets amplified in the PCR assays for detection of poisonous mushrooms have their counterparts in edible species, there is a need to design PCR primers specific to the genes encoding amanitins and phallotoxins, which occur only in poisonous mushrooms. Objective. The aim of the study was testing of PCR-based method for detection of all genes encoding hepatotoxic cyclic...
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Performance and Energy Aware Training of a Deep Neural Network in a Multi-GPU Environment with Power Capping
PublikacjaIn this paper we demonstrate that it is possible to obtain considerable improvement of performance and energy aware metrics for training of deep neural networks using a modern parallel multi-GPU system, by enforcing selected, non-default power caps on the GPUs. We measure the power and energy consumption of the whole node using a professional, certified hardware power meter. For a high performance workstation with 8 GPUs, we were...
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Regularity of weak solutions for aclass of elliptic PDEs in Orlicz-Sobolev spaces
PublikacjaWe consider the elliptic partial differential equation in the divergence form $$-\div(\nabla G(\nabla u(x))) t + F_u (x, u(x)) = 0,$$ where $G$ is a convex, anisotropic function satisfying certain growth and ellipticity conditions We prove that weak solutions in $W^{1,G}$ are in fact of class $W^{2,2}_{loc}\cap W^{1,\infty}_{loc}$.
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Corporate social responsibility and forward default risk under firm and industry heterogeneity
PublikacjaObjective: This study aims to evaluate the impact of corporate social responsibility on forward default risk (FDR) under the setting of firm and industry heterogeneity. Research Design & Methods: This study evaluated the impact of corporate social responsibility (CSR) on FDR using the data of 497 companies from 2007-2021 in the S&P 500 index, taking into account firm and industry heterogeneity aspects. This study utilized instrumental...
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Mountain pass solutions to Euler-Lagrange equations with general anisotropic operator
PublikacjaUsing the Mountain Pass Theorem we show that the problem \begin{equation*} \begin{cases} \frac{d}{dt}\Lcal_v(t,u(t),\dot u(t))=\Lcal_x(t,u(t),\dot u(t))\quad \text{ for a.e. }t\in[a,b]\\ u(a)=u(b)=0 \end{cases} \end{equation*} has a solution in anisotropic Orlicz-Sobolev space. We consider Lagrangian $\Lcal=F(t,x,v)+V(t,x)+\langle f(t), x\rangle$ with growth conditions determined by anisotropic G-function and some geometric conditions...
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Environmental impact of construction. Methods of conscious shaping architecture in terms of ecological solutions
PublikacjaShaping an ecologically conscious society is a process that also affects architecture. Currently, designers are eagerly looking for solutions that are beneficial in terms of carbon footprint. For the proper multi-criteria assessment and selection of adequate solutions, it is necessary to use appropriate tools such as, for example, the Life Cycle Assessment (LCA) method or the rules of ecological certification (BREEAM and LEED)....
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Cykl życia wyrobu a ochrona środowiska
PublikacjaW nienijszym rozdziale poruszono zagadnienia zwiazane z ochrona srodowiska- przedsatwiono genezę i rozwój koncepcji zarządzania środowiskiem. Przedstawiona została rózwnież problematyka wzajemnych oddziaływań przedsiebiorstwa i jego produktów na środowisko naturalne w aspekcie zarządzania środowiskowego i metody LCA(Life Cycle Assessment). Omówiono również zagadnienie związane z Zadsadą Przedłuzonej odpowiedzialności Producenta...
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Cryptocurrencies as a speculative asset. How much uncertainty is included in cryptocurrency price?
PublikacjaThe aim of this paper is to examine the relationship between uncertainty indices (Geopolitical Uncertainty Index and Global Economic Policy Uncertainty Index) and cryptocurrencies. In order to conduct research, the authors collected the data on the major cryptocurrencies (Bitcoin, Ethereum, Tether, Dogecoin and USD coin) which account for 78% of the total market cap. Using panel OLS regression, this study finds that Bitcoin...
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Rheology of liquid crystalline polymers
PublikacjaLiquid crystallinity was invented in the 19th century. It was sometimes called the fourth state of matter because of the ability of macromolecules to generate liquid crystal phases. The main classification divided liquid crystalline polymers (LCPs) into lyotropic and thermotropic types. Interpretation of the rheological behavior of LCP is more complicated than for other polymers. Ordinary polymers are characterized by a normal...
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Research on assessment of bolted joint state using elastic wave propagation
PublikacjaThe work contains results of experimental investigation of elastic wave propagation in a bolted single-lap joint. Tests were carried out for the excitation perpendicular to the connection plane. In experimental studies, PZT transducers were used for both excitation and registration of ultrasonic waves. The analyses took into account varying contact conditions between the elements of the connection depending on the value of the...
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Ranking of Heterogeneous Catalysts Metals by Their Greenness
PublikacjaCatalysis is very important process in industry and laboratory practice, especially from the point of green chemistry principles. However, eco-friendly character of heterogeneous catalysts, containing transition metal components has not been evaluated, yet. Therefore, we perform a comprehensive assessment of 18 heterogeneous metal catalysts (Pd, Pt, V, Co, Ni, Mo, Ru, Mn, Au, Cu, Cd, Zr, Fe, Rh, Ir, Sn, Zn, Ag) using multicriteria...
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Experimentation, material modelling and simulation of bonded joints with a flexible adhesive
PublikacjaThe paper deals with material parameters identification of a flexible adhesive and the numerical simulation of its behaviour in a single lap bonded joint. The material modelling was based on the simple shear and tensile-shear laboratory tests of the bonded joints made of thin aluminium and polyurethane plates with the flexible adhesive Terostat MS 9360 manufactured by Henkel AG & Co. The adhesive was considered as a hyperelastic...
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Artificial Neural Network based fatigue life assessment of riveted joints in AA2024 aluminum alloy plates and optimization of riveted joints parameters
PublikacjaThe objective of this paper is to provide the fatigue life of riveted joints in AA2024 aluminum alloy plates and optimization of riveted joints parameters. At first, the fatigue life of the riveted joints in AA2024 aluminum alloy plates is obtained by experimental tests. Then, an artificial neural network is applied to estimate the fatigue life of riveted lap joints based on the number of lateral and longitudinal holes, punch pressure,...
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Research on Tool Temperature Dependence on Lapping Grains Size
PublikacjaCommonly used as a finishing operation, lapping has been used for achieving ultra-high finishes and close tolerances between mating pieces. Its carried out by applying loose abrasive grains between work and lap surfaces, and causing a relative motion between them resulting in a finish of multi-directional lay. The grains activity (sliding and rolling) in the working gap causes not only the material removal but also the temperature...
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Sewage sludge co-pyrolysis with agricultural/forest residues: A comparative life-cycle assessment
PublikacjaThis study aims to determine the sustainability and energy efficiency of co-pyrolysis scenarios as treatment processes for municipal sewage sludge through a life cycle assessment (LCA). In addition, sensitivity and energy recovery analyses are conducted to determine the possible methods for optimizing the co-pyrolysis process from a circular bioeconomy perspective. Corncob and wood residue have been selected as potential co-feed...