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Search results for: finite-gap potential
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Bee Bread Exhibits Higher Antimicrobial Potential Compared to Bee Pollen
PublicationThis study aimed at investigation of the antimicrobial potential of ethanolic extracts of bee bread (BB) and bee pollen (BP) and suspensions of these products in MHB (Mueller Hinton Broth). We covered 30 samples of BP and 19 samples of BB harvested in Polish apiaries. Slightly lower activity was observed against Gram-negative bacteria compared to Gram-positive staphylococci. BB extracts exhibited higher inhibitory potential with...
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Linear-scaling calculation of Hartree-Fock exchange energy with Non-orthogonal Generalised Wannier Functions
PublicationWe present a method for the calculation of four-centre two-electron repulsion integrals in terms of localised non-orthogonal generalised Wannier functions (NGWFs). Our method has been imple- mented in the ONETEP program and is used to compute the Hartree-Fock exchange energy component of Hartree-Fock and Density Functional Theory (DFT) calculations with hybrid exchange-correlation functionals. As the NGWFs are optimised in situ...
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Shape-dependent enhanced photocatalytic effect under visible light of Ag3PO4 particles
PublicationSilver phosphate (Ag3PO4) could be considered as visible light induced photocatalyst for pollutants degradation, due to its narrow band gap (∼2.4 eV). However, Ag3PO4 photoactivity depends on surface properties and synthesis route. In this study, differently shaped Ag3PO4 photocatalysts have been synthesized through the precipitation, ion exchange, soft-chemical or hydrothermal method. To correlate surface properties with photoactivity all...
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Networkig activities of general judiciary - from theory to practice
PublicationOver the last three decades, networks - as a field of research - have acquired a significant place among management sciences. Unfortunately, in the judiciary they have become a subject of more careful analyses only recently, which resulted in a large discrepancy of knowledge - both in theory and in its practical adaptation for the needs of the courts. In order to fill this cognitive gap, an attempt was made to identify levels of...
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Introducing concurrent engineering to space and satellite technology undergraduate course
PublicationIn recent decade concurrent engineering has become a de facto leading methodology of work in space, aeronautics and sometimes even automotive industry. It has been used in designing ESA space missions for 20 years now, with rst Concurrent Design Facility (CDF) built in ESTEC in 1998. Still, it has not become a universal standard in engineering, and universities are specically reluctant to adopt it into their curricula. As a result,...
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Exploring the preferences of Polish EFL teachers towards the accents of English
PublicationThis language attitudes study investigates the preferences of EFL (English as a foreign language) teachers from Poland towards the accents of English they speak and teach. Despite the substantial amount of research on EFL learners, little has been done to investigate the impact of preferences of Polish teachers for different variations of English language on their...
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Nonlinear control of five phase induction motor with synchronized third harmonic flux injection
PublicationThe paper deals with the novel control system for five phase induction motor (IM) that enables the injection of the rotor flux 3rd harmonic component. Two multiscalar models are transformed from the 1-1 and 2-2 vector models developed in the 1st and 3rd harmonic planes. Based on the obtained multiscalar models the synthesis of dual multiscalar control is established. The obtained two multiscalar control systems can independently...
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A novel hybrid adaptive framework for support vector machine-based reliability analysis: A comparative study
PublicationThis study presents an innovative hybrid Adaptive Support Vector Machine - Monte Carlo Simulation (ASVM-MCS) framework for reliability analysis in complex engineering structures. These structures often involve highly nonlinear implicit functions, making traditional gradient-based first or second order reliability algorithms and Monte Carlo Simulation (MCS) time-consuming. The application of surrogate models has proven effective...
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Flow Maps and Flow Patterns of R1233zd(E) in a Circular Minichannel at Low, Medium and High Values of Saturation Pressure
PublicationThere is a gap in knowledge regarding the flow pattern of low-boiling working fluids in the range of high saturation temperatures (above 120°C) and medium and high reduced pressures (0.5-0.9). Data are present in the literature for similar values of reduced pressures, but for lower values of saturation temperature. This is due to the existing refrigeration applications of these working fluids. At high values of reduced pressure,...
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Impressions about people with intellectual disability of Polish high school students who participated in a workshop led by self-advocates
PublicationThe research question is whether participation in a two-session workshop led by self-advocates with mild intellectual disability, supported by professional staff, affects high school students’ impression of people with intellectual disability, measured by a self-report questionnaire based on a semantic differential. The study was paper-pencil questionnaire-based and anonymous, conducted in Warsaw, Poland. Three measurements...
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Earthquake-induced pounding between equal height multi-storey buildings considering soil-structure interaction
PublicationThe present paper investigates the coupled effect of the supporting soil flexibility and pounding between neighbouring, insufficiently separated equal height buildings under earthquake excitation. Two adjacent three-storey structures, modelled as inelastic lumped mass systems with different structural characteristics, have been considered in the study. The models have been excited using a suit of ground motions with different peak...
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Photocatalytic degradation and pollutant-oriented structure-activity analysis of carbamazepine, ibuprofen and acetaminophen over faceted TiO2
PublicationPhotocatalytic degradation of carbamazepine, ibuprofen, acetaminophen and phenol was studied in the presence of anatase photocatalyst, exposing three different crystal facets in the majority of {0 0 1}, {1 0 0} or {1 0 1}. It was found that octahedral anatase particles exposing {1 0 1} facets allow to achieve the best degradation and mineralization of all persistent organic pollutants. This confirms that the previous findings,...
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Merton-type default risk and financial performance: the dynamic panel moderation of firm size
PublicationPurpose – The main purpose of this study is to evaluate the probability of default and examine the relationship between default risk and financial performance, with dynamic panel moderation of firm size. Design/methodology/approach – This study utilizes a total of 1,500 firm-year observations from 2013 to 2018 using dynamic panel data approach of generalized method of moments to test the relationship between default risk and financial...
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Shape-controllable synthesis of GdVO4 photocatalysts and their tunable properties in photocatalytic hydrogen generation
PublicationNovel visible light responsive materials for water splitting are essential for the efficient conversion of solar energy into hydrogen bond energy. Among other semiconductors, gadolinium orthovanadate has appropriate conduction and valence band edges positioned to split water molecules and a narrow band gap that allows the use of visible light for hydrogen generation. Thus, we present here that hydrogen evolution under visible light...
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The culture of excellence and its dimensions in higher education
PublicationPurpose To recognize the existing state of knowledge on a culture of excellence (CoE) in higher education institutions (HEIs) and to define the CoE in HEI and the dimensions that make up that culture. A subsidiary goal is to propose a qualitative tool to measure CoE maturity. Design/methodology/approach The study was based on the qualitative method, the preferred reporting system of systematic reviews and meta-analysis (PRISMA)....
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Hydrophobic and hydrophilic properties of pollutants as a factor influencing their redistribution during snowpack melt
PublicationGlaciers accumulate organic pollutants delivered by snow. However, our understanding of the exact dynamics of organic pollutants in the snowpack relies primarily on laboratory experiments and mathematical models. To fill the gap related to the detailed field data, we have conducted observations of melting snow profiles in two locations and three different stages of melting on one High Arctic glacier, as well as in superimposed...
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Effect of Polymerization Statistics on the Electronic Properties of Copolymers for Organic Photovoltaics
PublicationStatistical block copolymers, composed of donor (D) and acceptor (A) blocks, are a novel type of material for organic photovoltaics (OPVs) devices. In particular a new series of polymers based on PBTZT-stat-BDTT-8, recently developed by Merck, offers high solubility in different solvents, and a high power conversion efficiency (PCE) in different device architectures. Although it is known that the electronic properties of these...
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Highly Dissipative Materials for Damage Protection against Earthquake-Induced Structural Pounding
PublicationIt is a common situation that seismic excitations may lead to collisions between adjacent civil engineering structures. This phenomenon, called earthquake-induced structural pounding, may result in serious damage or even the total collapse of the colliding structures. Filling the gap between two buildings erected close to one another by using visco-elastic materials can be considered to be one of the most effective methods to avoid...
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Real-time monitoring of volatiles and particles emitted from thermoplastic filaments during 3D printing
PublicationThe proliferation of consumer-grade three-dimensional (3D) printers using fused deposition, also known as fused filament fabrication, has given rise to concerns over the exposure of users to potentially harmful substances. Thermoplastic filaments made of different polymers are extruded through a heated printer nozzle and deposited layer by layer on a build platform to form the printed object. This process leads to the emission...
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Insight into Potassium Vanadates as Visible-Light-Driven Photocatalysts: Synthesis of V(IV)-Rich Nano/Microstructures for the Photodegradation of Methylene Blue
PublicationPhotocatalysis is regarded as a promising tool for wastewater remediation. In recent years, many studies have focused on investigating novel photocatalysts driven by visible light. In this study, K2V6O16·nH2O nanobelts and KV3O8 microplatelets were synthesized and investigated as photocatalysts. Samples were obtained via the facile method based on liquid-phase exfoliation with ion exchange. By changing the synthesis temperature...
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Determination of Peak Impact Force for Buildings Exposed to Structural Pounding during Earthquakes
PublicationStructural pounding between adjacent, insufficiently separated buildings, or bridge segments, has been repeatedly observed during seismic excitations. Such earthquake-induced collisions may cause severe structural damage or even lead to the collapse of colliding structures. The aim of the present paper was to show the results of the study focused on determination of peak impact forces during collisions between buildings exposed...
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COVID-19 and digital deprivation in Poland
PublicationResearch background: The problem of digital deprivation is already known, but the COVID-19 pandemic has highlighted its negative consequences. A global change in the way of life, work and socialisation resulting from the epidemic has indicated that a basic level of digital integration is becoming necessary. During the lockdown, people were forced to use ICTs to adapt to a rapidly changing reality. Current experience with coronavirus...
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Urban Lighting Research Transdisciplinary Framework—A Collaborative Process with Lighting Professionals
PublicationOver the past decades, lighting professionals have influenced the experience of the night by brightly illuminating streets, buildings, skylines, and landscapes 24/7. When this became the accepted norm, a dual perspective on night-time was shaped and the visual enjoyment of visitors after dusk was prioritized over natural nightscapes (nocturnal landscapes). During this time, researchers of artificial light at night (ALAN) observed...
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Assessing Acute Toxicity and Endocrine Disruption Potential of Selected Packages Internal Layers Extracts
PublicationThe focus of the present study is migration of toxic substances from food contact materials and its actual influence on the health of the final consumer. Two food packagings (metal cans, TetraPack®) and five simulants medias (water, ethanol, acetic acid, DMSO, artificial saliva) were selected for simulation studies. For assessment of acute toxicity and endocrine disruption potential of extract samples, two biotests (Microtox® and...
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Investigating BiMeVOx compounds as potential photoelectrochemical and electrochemical materials for renewable hydrogen production
PublicationIn this study, BiMeVOx compounds (where Me: Co, Mo, Ce, Zr) were synthesized and characterized as potential photoelectrochemical materials for solar water splitting, the hydrogen evolution reaction (HER), and oxygen evolution reaction (OER). The analysis confirmed the successful formation of phase BiMeVOx compounds with the desired crystal structure. Among the tested materials, BiCoVOx(800) showed the highest photocurrent density...
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BIOGAS PRODUCTION FROM BAKERY WASTES -DYNAMICS, RETENTION TIME AND BIOGAS POTENTIAL
PublicationThis paper presents results of bakery-waste methane-fermentation. The scope of the study covers the determination of basic physicochemical parameters, process dynamics and retention time as well as biogas composition and biogas efficiency. Methane fermentation process was carried out in accordance with German Standard DIN 38414 S8 and under condition of 38°C. Conclusion: bakery wastes have big potential for biogas production.
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Potential Toxic Effects of Airport Runoff Water Samples on the Environment
PublicationDespite the positive aspects of the intensive development of aviation, airports are considered large-scale polluters. Pollution caused by runoff water (stormwater) is one of the major problems related to airport operations. The aim of this study was to characterize the potential toxic impact on aquatic life from runoff water discharges from four international airports in Europe. Samples of stormwater were collected at airports...
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The synthesis and structure of a potential immunosuppressant: N-mycophenoyl malonic acid dimethyl ester
PublicationThe synthesis of a potential immunosuppressant, i.e. dimethyl ester of N-mycophenoyl malonic acid was optimized in the reaction of mycophenolic acid (MPA) with amino malonic dimethyl ester in the presence of propanephosphonic anhydride (T3P) as a coupling reagent. The structural properties of the obtained MPA derivative were investigated by NMR, MS and single crystal X-ray diffraction methods. Theoretical considerations of conformational...
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An Efficient Framework For Fast Computer Aided Design of Microwave Circuits Based on the Higher-Order 3D Finite-Element Method
PublicationIn this paper, an efficient computational framework for the full-wave design by optimization of complex microwave passive devices, such as antennas, filters, and multiplexers, is described. The framework consists of a computational engine, a 3D object modeler, and a graphical user interface. The computational engine, which is based on a finite element method with curvilinear higher-order tetrahedral elements, is coupled with built-in...
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High-temperature heat pumps – potential technology for heat recovery and production of process heat
PublicationIn the paper, the high temperature vapour compressor based heat pump with a selection of working fluids, both perspective and ecological ones, is considered. Such system is not yet commercially available on the market and in author’s opinion it has significant potential for various applications. In the presented analysis it was assumed that the heat source has a temperature of 50oC and the temperature lift is 60, 80 and 100K respectively....
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Born–Oppenheimer potential energy curves of NaK from the optimised atomic basis sets
PublicationThe article presents adiabatic potential energy curves of the ground and excited electronic states for the diatomic NaK molecule. The calculations were made using the ab initio computational methods to include electron correlation. The studied molecule was calculated as the effective two-electron problem, in which only the valence electrons of the molecule are explicitly taken into account. The remaining electrons with atomic nuclei...
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Li nucleation on the graphite anode under potential control in Li-ion batteries
PublicationApplication of Li-ion batteries in electric vehicles requires improved safety, increased lifetime and high charging rates. One of the most commonly used intercalation anode material for Li-ion batteries, graphite, is vulnerable to Li nucleation, a side reaction which competes with the intercalation process and leads to loss of reversible capacity of the battery, ageing and short-circuits. In this study, we deploy a combined grand...
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ASSESSMENT OF TOXIC EFFECT AND ENDOCRINE POTENTIAL OF FOOD PACKAGES EXTRACTS
PublicationIn the scientific literature related to the widely understood issue of packaging materials designed to have contact with food there is much information on raw materials used for their production, their physiochemical properties, types and parameters. There is also a great number of publications on the management and disposal of used packaging. Unfortunately, not much attention is given to the matters concerning migration of toxic...
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Ground-State Entanglement Properties of Helium Atom in a Finite Spherical Cavity
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An Enhanced Reduced Basis Method for Wideband Finite Element Method Simulations
PublicationIn this paper, we present a novel strategy for selecting expansion points in the reduced basis method. A single computation of the error estimator is used to select a few expansion points in the multi-parameter space simultaneously. The number of selected points is determined adaptively, based on the accuracy of the current reduced model. The reliability and efficiency of this proposed approach are illustrated by numerical tests...
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Modal energy identification of large stucture idealised by the finite element method
PublicationPrzedstawiono metodę określania energii drgań układów dyskretnych otrzyma-nych w wyniku modelowania metodą elementów skończonych wybranych fragmentów konstrukcji samochodów. W odróżnieniu od poprzednio stosowanych podejść, ro-zważa się całkowite energie mechaniczne odpowiadające poszczególnym posta-ciom drgań własnych. Całkowitą energię mechaniczną oblicza się na podstawie parametrów modelu modalnego. Energię mechaniczną można...
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Modelling of the finite amplitude waves interaction problem inside truncated cone.
PublicationModel matematyczny zjawiska oddziaływania fal o dużej amplitudzie dla przetwornika kołowego zbudowanego w oparciu o równanie KZK. Rozwiązania zagadnienia poszukiwano wewnątrz stożka ściętego. Do rozwiązania zagadnienia zastosowano metodę różnic skończonych. Podano przykładowe wyniki badań numerycznych.
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Finite difference approximations for nonlinear first order partial differential equations
PublicationKlasyczne rozwiązania nieliniowych równań różniczkowych o pochodnych cząst-kowych pierwszego rzędu są aproksymowane za pomocą równań quasiliniowych uk-ładów równań różniczkowych. Dowód zbieżności wykorzystuje metody porównawcze
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Analysis of unsteady pipe flow using the modified finite element method
PublicationW pracy przedstawiono rozwiązanie równania przepływu nieustalonego zmodyfikowaną metodą elementów skończonych. Podejście to prowadzi do 6-punktowego schematu niejawnego z dwoma parametrami wagowymi. Analiza dokładności wykonana metodą równania zmodyfikowanego wykazała, że zaproponowany schemat zapewnia wyższą dokładność rozwiązania niż inne schematy. Porównanie wyników obliczeń z wynikami eksperymentu fizycznego wskazuje, że ich...
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Propagation of elastic waves in structural elements by spectral finite element methods
PublicationW pracy przedstawiono metodę elementów spektralnych w zastosowaniu do analizy propagacji fal sprężystych w elementach konstrukcyjnych.
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Assessment of rod behavior theories used in spectral finite element modeling
PublicationW pracy przedstawiono teorie prętów i przedstawiono ich przydatnośc w analizie propagacji fal sprężystych z wykorzystaniem metody spektralnych elementów skończonych.
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Wave propagation modelling in 1D structures using spectral finite elements
PublicationW artykule omówiono modele propagacji fal wzdłużnych i poprzecznych w prętach oparte na dwóch sformułowaniach (w dziedzinie częstości i w dziedzinie czasu) metody elemntów spektralnych. Porównano otrzymane wyniki z wynikami eksperymentu.
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Geometrically nonlinear finite element simulation of smart piezolaminated plates and shells
PublicationW pracy zaproponowano powłokowy element skończony pozwalający na uwzględnienie efektu piezoelektrycznego. Element został wykorzystany w podejściu Lagrange'a, które wymaga starannego dobrania definicji wielkości mechanicznych i elektrycznych. Zależności przemieszczenie-odkształcenie zbudowano na bazie teorii małych odkształceń i umiarkowanych obrotów. Założono liniowy rozkład pól odkształceń i pola elektrycznego po grubości powłoki....
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Review of constitutive models for technical woven fabrics in finite element analysis
PublicationArtykuł opisuje typy modeli konstytutywnych stosowanych do opisu zachowania się tkanin technicznych w analizie MES. Proponowany jest także warstwowy model sieci gęstej.
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Modeling of the finite amplitude plane wave propagation in non-dissipative medium
PublicationPraca prezentuje wyniki analizy teoretycznej zagadnienia propagacji fali płaskiej o skończonej amplitudzie w ośrodku wodnym bez dyssypacji. Przedstawiono model matematyczny i przykładowe wyniki obliczeń numerycznych. Model matematyczny zbudowano w oparciu o jednowymiarowe równania mechaniki płynów. Do rozwiązania zagadnienia zastosowano metodę różnic skończonych. Analizowano zmiany ciśnienia i zmiany widma. Badano zbieżność i dokładność...
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Quantum-correlation breaking channels, broadcasting scenarios, and finite Markov chains
PublicationOne of the classical results concerning quantum channels is the characterization of entanglementbreakingchannels [M. Horodecki et al., Rev. Math. Phys 15, 629 (2003)]. We address the questionwhether there exists a similar characterization on the level of quantum correlations which may gobeyond entanglement. The answer is fully affirmative in the case of breaking quantum correlationsdown to the, so called, QC (Quantum-Classical)...
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Finite element modeling of shear localization in granular bodies in hypoplasticity with enhancements
PublicationW pracy omówiono wyniki numeryczne lokalizacji okształceń stycznych w materiałach granulowanych. Obliczenia wykonano stosując prawo hipoplastyczne z rozszerzeniami w ramach mechaniki ośrodka gradientowego, nielokalnego i mikropolarnego. Obliczenia przeprowadzono dla różnych problemów brzegowych z uwzględnieniem lokalizacji. Wyniki analiz porównano z doświadczeniami.
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Analyzing Wind Energy Potential Using Efficient Global Optimization: A Case Study for the City Gdańsk in Poland
PublicationWind energy (WE), which is one of the renewable energy (RE) sources for generating electricity, has been making a significant contribution to obtaining clean and green energy in recent years. Fitting an appropriate statistical distribution to the wind speed (WS) data is crucial in analyzing and estimating WE potential. Once the best suitable statistical distribution for WS data is determined, WE potential and potential yield could...
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Therapeutic Potential of Carnosine and Its Derivatives in the Treatment of Human Diseases
PublicationDespite significant progress in the pathogenesis, diagnosis, treatment, and prevention of cancer and neurodegenerative diseases, their occurrence and mortality are still high around theworld. The resistance of cancer cells to the drugs remains a significant problem in oncology today,while in the case of neuro-degenerative diseases, therapies reversing the process are still yet to be found. Furthermore, it is important to seek new...
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Potential energy surfaces of the low-lying electronic states of the Li+LiCs system
Open Research DataThis data presents potential energy surfaces of Li atom interacting with LiCs dimer for the ground and first excited state. They were calculated using effective core potentials and MRCI method and include relativistic effects. The interatomic distance in the dimer is kept constant and equal to experimental value of 6.931704423 bohrs (3.6681 A). Energy...