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  • Matematyczny świat wirusów i bakterii
    • Agnieszka Bartłomiejczyk
    2022

    Kiedyś, mówiąc o zastosowaniach matematyki, przychodziła nam na myśl głównie fizyka. Dziś wiemy, że matematyka ma ważne zastosowania również w biologii i medycynie. To, jak szybko rozwijają się bakterie i wirusy oraz jak szybko odpowiada na ich obecność nasz układ odpornościowy, można opisać językiem matematyki. Głównym narzędziem służącym do opisu tempa zmiany interesującej nas wielkości jest pochodna. Dzięki pochodnej możemy przewidzieć wzrost lub spadek liczby zachorowań, np. na grypę czy COVID-19, co pozwala nam na podjęcie skutecznych działań zapobiegających rozwojowi pandemii.

  • Mater-Bi/Brewers’ Spent Grain Biocomposites—Novel Approach to Plant-Based Waste Filler Treatment by Highly Efficient Thermomechanical and Chemical Methods
    • Aleksander Hejna
    • Mateusz Barczewski
    • Paulina Kosmela
    • Olga Mysiukiewicz
    • Paweł Sulima
    • Jerzy Andrzej Przyborowski
    • Daria Kowalkowska-Zedler
    2022 Pełny tekst Materials

    Thermoplastic starch (TPS) is a homogenous material prepared from native starch and water or other plasticizers subjected to mixing at a temperature exceeding starch gelatinization temperature. It shows major drawbacks like high moisture sensitivity, poor mechanical properties, and thermal stability. To overcome these drawbacks without significant cost increase, TPS could be blended with bio-based or biodegradable polymers and filled with plant-based fillers, beneficially waste-based, like brewers’ spent grain (BSG), the main brewing by-product. Filler modifications are often required to enhance the compatibility of such composites. Herein, we investigated the impact of BSG thermomechanical and chemical treatments on the structure, physical, thermal, and rheological performance of Mater-Bi-based composites. Thermomechanical modifications enhanced matrix thermal stability under oxidative conditions delaying degradation onset by 33 ◦C. Moreover, BSG enhanced the crystallization of the polybutylene adipate terephthalate (PBAT) fraction of Mater-Bi, potentially improving mechanical properties and shortening processing time. BSG chemical treatment with isophorone diisocyanate improved the processing properties of the composites, expressed by a 33% rise in melt flow index. Depending on the waste filler’s selected treatment, processing, and rheological performance, thermal stability or interfacial adhesion of composites could be enhanced. Moreover, the appearance of the final materials could be adjusted by filler selection.

  • Material characterisation of biaxial glass-fibre non-crimp fabrics as a function of ply orientation, stitch pattern, stitch length and stitch tension
    • Philipp Quenzel
    • Hauke Kröger
    • Boris Manin
    • Khiêm Ngoc Vu
    • Thang X. Duong
    • Thomas Gries
    • Mikhail Itskov
    • Roger Sauer
    2022 Pełny tekst JOURNAL OF COMPOSITE MATERIALS

    Due to their high density-specific stiffnesses and strength, fibre reinforced plastic (FRP) composites are particularly interesting for mobility and transport applications. Warp-knitted non-crimp fabrics (NCF) are one possible way to produce such FRP composites. They are advantageous because of their low production costs and the ability to tailor the properties of the textile to the reinforcement and drape requirements of the application. Based on their specific production parameters, their draping properties can vary significantly. Draping simulations are used to predict the forming behaviour without relying on costly and time consuming trial and error experiments. However, these simulations require a broad material dataset to make accurate predictions. Previous studies have investigated the relationships between production parameters and drape behaviour only in isolation for a limited number of material parameters at a time. In this study, a comprehensive material characterisation is carried out. The influence of ply orientation, stitch pattern, stitch length and stitch tension on the tensile and bending properties and the friction, shear and drape behaviour of NCFs are investigated on a meso and macro scale. Furthermore, the inter-ply sliding phenomena in bias extension tests are analysed and the results of bias extension and picture frame tests are compared.

  • Material Design and Optimisation of Electrochemical Li-Ion Storage Properties of Ternary Silicon Oxycarbide/Graphite/Tin Nanocomposites
    • Dominik Knozowski
    • Pradeep Vallachira Warriam Sasikumar
    • Piotr Madajski
    • Gurdial Blugan
    • Maria Gazda
    • Natalia Kovalska
    • Monika Wilamowska-Zawłocka
    2022 Pełny tekst Nanomaterials

    In this work, we present the characterization and electrochemical performance of various ternary silicon oxycarbide/graphite/tin (SiOC/C/Sn) nanocomposites as anodes for lithium-ion batteries. In binary SiOC/Sn composites, tin nanoparticles may be produced in situ via carbothermal reduction of SnO2 to metallic Sn, which consumes free carbon from the SiOC ceramic phase, thereby limiting the carbon content in the final ceramic nanocomposite. Therefore, to avoid drawbacks with carbon depletion, we used graphite as a substitute during the synthesis of precursors. The ternary composites were synthesized from liquid precursors and flake graphite using the ultrasound-assisted hydrosilylation method and pyrolysis at 1000 °C in an Ar atmosphere. The role of the graphitic component is to ensure good electric conductivity and the softness of the material, which are crucial for long term stability during alloying–dealloying processes. The presented approach allows us to increase the content of the tin precursor from 40 wt.% to 60 wt.% without losing the electrochemical stability of the final material. The charge/discharge capacity (at 372 mA g−1 current rate) of the tailored SiOC/C/Sn composite is about 100 mAh g−1 higher compared with that of the binary SiOC/Sn composite. The ternary composites, however, are more sensitive to high current rates (above 372 mA g−1) compared to the binary one because of the presence of graphitic carbon.

  • Mathematical Approach to Assess a Human Gait
    • Wiktoria Wojnicz
    • Bartłomiej Zagrodny
    • Michał Ludwicki
    • Jan Awrejcewicz
    2022

    A purpose of the paper was to create a mathematical approach to assess a human gait. The scope of the study was to model a normal gait in the sagittal plane and frontal plane of the body. Applying the Newton-Euler formulation, three multibody biomechanical models were derived to describe single support phase and double support phase of the gait. To model a gait in the sagittal plane the open-close sagittal 6DOF model and the open-close sagittal 7DOF model can be used. To model a gait in the frontal plane the open-close frontal 7DOF model can be applied. Presented multibody models can be used to solve a forward dynamic task or an inverse dynamic task.

  • Mathematical model to assess energy consumption using water inflow-drainage system of iron-ore mines in terms of a stochastic process
    • Oleg Sinchuk
    • Ryszard Strzelecki
    • Igor Sinchuk
    • Теtуаnа Веridzе
    • Vladyslav Fedotov
    • Vladyslav Baranovskyi
    • Kyrylo Budnikov
    2022 Pełny tekst Mining of Mineral Deposits

    Purpose is to develop a unified mathematical model to assess energy efficiency of a water inflow-drainage process as the real variant of stochastic method for water pumping from underground workings of iron-ore mines. Methods. The research process was based upon the methods of probability theory as well as stochastic modelling methods. The stochastic function integration has been reduced to summation of its ordinates and further transition to a proper boundary. Findings. A mathematical model of a water inflow-drainage system as a stochastic process has been developed in terms of input parameters of a standard operating iron-ore mine. The abovementioned has made it possible to assess realistically, substantiate, and obtain possibilities for a specific production facility as well as for generalization of the results involving determination of stochastic characteristics of drainage process. Originality. For the first time, a mathematical model of drainage from underground levels of iron-ore mines has been developed as a stochastic process. The process characteristics have been identified relying upon randomness of a water pumping technique. In contrast to the available settings, the new model parameters characterize their dispersion. Possibility to obtain complete characteristics of energy consumption has been obtained: for drainage; for water accumulation volume in underground water collectors; for water pumping from the specified mine depths over the specific period as random processes. A number of drainage features have been analyzed and differentiated being determined with the help of normal law of water accumulation velocity in the underground water collectors in iron-ore mines. Practical implications. In terms of operating iron-ore mine, a generalized drainage mathematical model has been developed as a stochastic process using statistical data concerning water accumulation velocity in the underground water collectors. It has been proved that if the ordinates of water accumulation velocity in the underground water collectors obey the normal distribution law then it is expedient to characterize drainage as a stochastic process. The developed methods, studying drainage as a stochastic process, help expand the research boundaries involving other auxiliary operations performed during underground mining of iron ore raw materials.

  • Mathematical modelling of gasification process of sewage sludge in reactor of negative CO2 emission power plant
    • Paweł Ziółkowski
    • Janusz Badur
    • Halina Pawlak-kruczek
    • Kamil Stasiak
    • Milad Amiri
    • Lukasz Niedzwiecki
    • Krystian Krochmalny
    • Jakub Mularski
    • Paweł Madejski
    • Dariusz Mikielewicz
    2022 Pełny tekst ENERGY

    Sewage sludge is a residue of wastewater processing that is biologically active and consists of water,organic matter, including dead and alive pathogens, as well as organic and inorganic contaminants suchas polycyclic aromatic hydrocarbons (PAHs) and heavy metals. Due to the nature of sewage sludge and itspossible influence on human health and wellbeing, it is a subject of various regulations. Currently,sewage sludge is considered as biomass, according to the new Polish act on renewable energy sources ofFebruary 20, 2015 and its novel version of July 19, 2019. This study presents a novel model, along with acomparison with experimental results. The model could be used for sewage sludge gasification modellingfor accurate assessment of the performance of novel concepts bioenergy with carbon capture and storage(BECCS) installations, using sewage sludge as a fuel. The composition of the dry produced gas, deter-mined experimentally, yields: XCO¼0.093, XCO2¼0.264, XCH4¼0.139, XCxHy¼0.035, and XH2¼0.468.Performed modifications to the original Deringer-with-Gumz-modification gasification model allowed toobtain good agreement with the experimental results, reaching XCO¼0.071, XCO2¼0.243, XCH4¼0.139,XC3H8¼0.035, and XH2¼0.512. The main novelty in the formulas of the internal model was due topropane inclusion, which was not found in the literature before. Additionally, sulphur dioxide wasapplied in exchange for other sulphur components presented in the original model. Equilibrium con-stants were adjusted to suit the experimental model. For ease of calculation, the own code was used toiterate multiple temperatures. Included was the energy balance equation that is essential for verification

  • Maxillary sinus aeration analysis using computational fluid dynamics
    • Dmitry Tretiakow
    • Krzysztof Tesch
    • Karolina Markiet
    • Andrzej Skorek
    2022 Pełny tekst Scientific Reports

    The maxillary sinus aeration using the computational fluid dynamics (CFD) method based on individual adult patients’ computed tomography (CT) scans were analyzed. The analysis was based on CT images of 4 patients: one with normal nose anatomy and three with nasal septal deviation (NSD) and concha bullosa (CB). The CFD simulation was performed using the Reynolds-Average Simulation approach and turbulence closure based on linear eddy viscosity supplemented with the two-equation k-\(\omega\) SST model. As a result, it was found that the lower part of NSD has the most significant impact on the airflow change within the maxillary sinuses compared to CB and the upper part of NSD. In a healthy nose, the airflow in the sinuses is continuous, while NSD and CB change this flow into pulsatile. Multiple changes in the direction of flow during one respiratory phase were observed. The flow intensity within the maxillary sinus opening is lower on the NSD side. The concept of vorticity measure is introduced to evaluate and compare various patients qualitatively. Typically, the lowest values of such measures are obtained for healthy airways and the highest for pathological changes in the nasal cavity.

  • May Staphylococcus lugdunensis Be an Etiological Factor of Chronic Maxillary Sinuses Infection?
    • Maja Kosecka-Strojek
    • Mariola Wolska-Gębarzewska
    • Adrianna Podbielska-Kubera
    • Alfred Samet
    • Beata Krawczyk
    • Jacek Międzobrodzki
    • Michał Michalik
    2022 Pełny tekst INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES

    Staphylococcus lugdunensis is an opportunistic pathogen found in the healthy human skin microbiome bacterial community that is able to cause infections of diverse localization, manifestation, and course, including laryngological infections, such as necrotizing sinusitis. Chronic maxillary sinusitis is a disease present in up to one third of European and American populations, and its etiology is not fully described. Within this study, we aimed to characterize 18 S. lugdunensis strains recovered from maxillary sinuses and evaluate them as etiological agents of chronic disease. We performed MLST analysis, the complex analysis of both phenotypic and genetic virulence factors, antibiotic susceptibility profiles, and biofilm formation assay for the detection of biofilm-associated genes. Altogether, S. lugdunensis strains were clustered into eight different STs, and we demonstrated several virulence factors associated with the chronic disease. All tested strains were able to produce biofilm in vitro with numerous strains with a very strong ability, and overall, they were mostly susceptible to antibiotics, although we found resistance to fosfomycin, erythromycin, and clindamycin in several strains. We believe that further in-depth analysis of S. lugdunensis strains from different niches, including the nasal one, should be performed in the future in order to reduce infection rate and broaden the knowledge about this opportunistic pathogen that is gaining attention.

  • Meandry życiowe Henryka Bajduszewskiego
    • Dariusz Świsulski
    2022 Pełny tekst Śląskie Wiadomości Elektryczne

    W artykule przedstawiono książkę Henryka Bajduszewskiego „Moje meandry życiowe”. Zawiera ona pamiętniki spisywane przez autora w czasie II wojny światowej w niemieckim wojsku we Francji oraz w wojsku polskim we Włoszech. Pamiętniki te zostały współcześnie uzupełnione o wspomnienia z czasów młodości, a także nauki i pracy po wojnie.

  • Measurement method for capacitive sensors for microcontrollers based on a phase shifter
    • Zbigniew Czaja
    2022 Pełny tekst MEASUREMENT

    A complete measurement method dedicated to capacitive sensors has been developed. It includes the development of hardware (an analogue interface circuit for microcontrollers with built-in times/counters and analogue comparators) and software (a measurement procedure and a systematic error calibration (correction) algorithm which is based on a calibration dictionary). The interface circuit consists of a low-pass filter and a phase shifter with a capacitive sensor. A prototype circuit based on a mid-range 8-bit microcontroller has been developed and investigated. We also analysed the relative inaccuracy of a measured capacitance of the sensor and performed experimental research. We obtained the relative errors of capacitance determination < 0.06%, which gives a measurement accuracy < 72 fF for the assumed range of the capacitance (100 pF – 300 pF).

  • Measurement of the Temporal and Spatial Temperature Distribution on the Surface of PVCP Tissue Phantom Illuminated by Laser Dataset
    • Anna Sękowska-Namiotko
    2022 Pełny tekst

    The dataset entitled Measurement of the temporal and spatial temperature distribution on the surface of PVCP tissue phantom illuminated by laser was obtained with a laboratory set-up for characterisation of the thermal properties of optical tissue phantoms during laser irradiation. The dataset contains a single image file representing the spatial temperature distribution on the surface of a PVCP tissue phantom. This thermal image was captured at the moment when the temperature reached its maximum value as a result of irradiation with a dermatological laser.

  • Measurements of Dispersed Phase Velocity in Two-Phase Flows in Pipelines Using Gamma-Absorption Technique and Phase of the Cross-Spectral Density Function
    • Robert Hanus
    • Marcin Zych
    • Anna Golijanek-Jędrzejczyk
    2022 Pełny tekst ENERGIES

    This paper concerns the application of the gamma radiation absorption method in the measurements of dispersed phase velocity in two-phase flows: liquid–gas flow in a horizontal pipe- line and liquid–solid particles in a vertical pipe. Radiometric sets containing two linear 241Am gamma radiation sources and two NaI(Tl) scintillation detectors were used in the research. Due to the stochastic nature of the signals obtained from the scintillation probes, statistical methods were used for their analysis. The linear average velocity of the dispersed phase transportation was calcu- lated using the phase of the cross-spectral density function of the signals registered by the scintilla- tion detectors. It is shown that in the presented cases, the phase method can be more accurate than the most commonly used classical cross-correlation one.

  • Measurements of Two-phase Flows in Pipelines Using Radioisotopes and Statistical Signal Processing
    • Robert Hanus
    • Marcin Zych
    • Anna Golijanek-Jędrzejczyk
    2022 Pełny tekst

    This paper presents an application of radiotracers and gamma absorption method in two-phase flow measurements in pipelines. Two different methods were implemented to analysis of acquired signals. Investigated methods are based on the cross-correlation function and the phase of the cross-spectral density distribution. The examples presented in the article illustrate the application of the radioisotopes to evaluation of liquid-gas flow in a horizontal pipe and liquid-solid particles flow in a vertical pipe.

  • Mechanical and physical assessment of epoxy, mineral, solvent-based, and water-soluble coating materials
    • Ginneth Millan Ramirez
    • Hubert Byliński
    • Maciej Niedostatkiewicz
    2022 Pełny tekst Scientific Reports

    This paper assesses the behavior of mineral, epoxy (EP), solvent, and water-soluble coatings when exposed to salt and regular water for 28 days. Also, it evaluates the pull-off adhesion strength of the same coating materials applied to concrete slabs saturated with oil and water and dried with two different processes: air-dried for 28 days and air-dried for 14 days plus 14 days in the oven at 70 °C. Properties such as carbonation, water absorption rate, pull-off adhesion strength were evaluated for all coatings, and tensile strength, Young’s modulus, and elongation percentage were calculated for mineral coatings. According to the results, the EP coating showed the best performance with the highest pull-off adhesion strength (2.55 MPa) and lowest absorption rate, about 0.02 ± 0.002 g/m2 day in saltwater and 0.03 ± 0.002 g/m2 day in regular water. In addition, EP coatings also presented the lowest carbonation rate and the highest suppress ratio. The excellent performance of epoxy coatings is mainly due to their low porosity and the ability to decrease chloride diffusion, making them better than other types of coatings investigated in this study.

  • Mechanical Behavior of Plastic Strips-Reinforced Expansive Soils Stabilized with Waste Marble Dust
    • Shelema Amena
    • Worku Firomsa Kabeta
    2022 Pełny tekst Advances in Civil Engineering

    Expansive 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 soil by adding 10, 15, and 20% of marble and 0.25, 0.5, and 0.75% of 5 × 8 mm² plastic strips. The laboratory test results showed that there are good enhancements on strength parameters due to the addition of marble dust and plastic strips. With an increase in percentages of marble dust and plastic strips, California Bearing Ratio (CBR) values rise. With the addition of marble dust, unconfined compressive strength (UCS) values increase linearly, while they increase only up to 0.5% with the addition of plastic strips. As the proportions of marble dust and plastic strips increase, the soil’s free swell and CBR swell are decreased significantly. This shows that environmental pollution waste marble dust and plastic strips can be utilized to strengthen the weak subgrade soil and minimize its swelling properties. Therefore, this study found out that the expansive soil treated with polyethylene terephthalate (PET) plastic and marble dust can be used as a subgrade material since it fulfills the minimum requirement needed by standards.

  • Mechanical Properties of Human Stomach Tissue
    • Szymon Grymek
    2022 Pełny tekst

    The dataset entitled Determination of mechanical properties of human stomach tissues subjected to uniaxial stretching contains: the length of the sample as a function of the corresponding load (tensile force) and the initial values of the average width and average thickness of the sample. All tests were conducted in a self-developed tensile test machine: PG TissueTester. The dataset allows the coefficients of various models of incompressible and nearly incompressible hyperelastic materials used to model human tissues to be determined.

  • Mechanism of hopping conduction in Be–Fe–Al–Te–O semiconducting glasses and glass–ceramics
    • Natalia Wójcik
    • Nagia S. Tagiara
    • Doris Möncke
    • Efstratios Kamitsos
    • Sharafat Ali
    • Jacek Ryl
    • Ryszard Barczyński
    2022 Pełny tekst JOURNAL OF MATERIALS SCIENCE

    Electrical properties of beryllium-alumino-tellurite glasses and glass–ceramics doped with iron ions were studied using impedance spectroscopy. The conductivity was measured over a wide frequency range from 10 mHz to 1 MHz and the temperature range from 213 to 473 K. The D.C. conductivity values showed a correlation with the Fe-ion concentration and ratio of iron ions on different valence states in the samples. On the basis of Jonscher universal dielectric response the temperature dependence of conductivity parameters were determined and compared to theoretical models collected by Elliott. In glasses, the conduction process was found to be due to the overlap polaron tunneling while in glass–ceramics the quantum mechanical tunneling between semiconducting crystallites of iron oxides is proposed. The D.C. conductivity was found not to follow Arrhenius relation. The Schnakenberg model was used to analyze the conductivity behavior and the polaron hopping energy and disorder energy were estimated. Additionally, the correlation between alumina dissolution and basicity of the melts was observed.

  • Mechanism of Osmolyte Stabilization–Destabilization of Proteins: Experimental Evidence
    • Marcin Stasiulewicz
    • Aneta Panuszko
    • Piotr Bruździak
    • Janusz Stangret
    2022 Pełny tekst JOURNAL OF PHYSICAL CHEMISTRY B

    In this work, we investigated the influence of stabilizing (N,N,N-trimethylglycine) and destabilizing (urea) osmolytes on the hydration spheres of biomacromolecules in folded forms (trpzip-1 peptide and hen egg white lysozyme─hewl) and unfolded protein models (glycine─GLY and N-methylglycine─NMG) by means of infrared spectroscopy. GLY and NMG were clearly limited as minimal models for unfolded proteins and should be treated with caution. We isolated the spectral share of water changed simultaneously by the biomacromolecule/model molecule and the osmolyte, which allowed us to provide unambiguous experimental arguments for the mechanism of stabilization/destabilization of proteins by osmolytes. In the case of both types of osmolytes, the decisive factor determining the equilibrium folded/unfolded state of protein was the enthalpy effect exerted on the hydration spheres of proteins in both forms. In the case of stabilizing osmolytes, enthalpy was also favored by entropy, as the unfolded state of a protein was more entropically destabilized than the folded state.

  • Mechanism of reaction of RNA-dependent RNA polymerase from SARS-CoV-2
    • Juan Aranda
    • Miłosz Wieczór
    • Montserrat Terrazas
    • Isabelle Brun-Heath
    • Modesto Orozco
    2022 Pełny tekst Chem Catalysis

    We combine molecular dynamics, statistical mechanics, and hybrid quantum mechanics/molecular mechanics simulations to describe mechanistically the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA-dependent RNA polymerase (RdRp). Our study analyzes the binding mode of both natural triphosphate substrates as well as remdesivir triphosphate (the active form of drug), which is bound preferentially over ATP by RdRp while being poorly recognized by human RNA polymerase II (RNA Pol II). A comparison of incorporation rates between natural and antiviral nucleotides shows that remdesivir is incorporated more slowly into the nascent RNA compared with ATP, leading to an RNA duplex that is structurally very similar to an unmodified one, arguing against the hypothesis that remdesivir is a competitive inhibitor of ATP. We characterize the entire mechanism of reaction, finding that viral RdRp is highly processive and displays a higher catalytic rate of incorporation than human RNA Pol II. Overall, our study provides the first detailed explanation of the replication mechanism of RdRp.

  • Medical Image Segmentation Using Deep Semantic-based Methods: A Review of Techniques, Applications and Emerging Trends
    • Imran Qureshi
    • Junhua Yan
    • Qaisar Abbas
    • Kashif Shaheed
    • Awais Bin Riaz
    • Abdul Wahid
    • Muhammad Waseem Jan Khan
    • Piotr Szczuko
    2022 Information Fusion

    Semantic-based segmentation (Semseg) methods play an essential part in medical imaging analysis to improve the diagnostic process. In Semseg technique, every pixel of an image is classified into an instance, where each class is corresponded by an instance. In particular, the semantic segmentation can be used by many medical experts in the domain of radiology, ophthalmologists, dermatologist, and image-guided radiotherapy. The authors present perspectives on the development of an architectural, and operational mechanism of each machine learning-based semantic segmentation approach with merits and demerits. In this regard, researchers have proposed different Semseg methods and examined their performance in a variety of applications such as medical image analysis (e.g., medical image classification and segmentation). A review of recent advances in Semseg techniques are presented in this paper by applying computational image processing and machine learning methods. This article is further presented a comprehensive investigation on how different architectures are helpful for medical image segmentation. Finally, advantages, open challenges, and possible future directions are elaborated in the discussion part, beneficial to the research community to understand the significance of the available medical imaging segmentation technology based on Semseg and thus deliver robust segmentation solutions.

  • MEMORY EFFECT ANALYSIS USING PIECEWISE CUBIC B-SPLINE OF TIME FRACTIONAL DIFFUSION EQUATION
    • Madiha Shafiq
    • Farah Aini Abdullah
    • Muhammad Abbas
    • Ahmed Sm Alzaidi
    • Muhammad Riaz
    2022 Pełny tekst FRACTALS-COMPLEX GEOMETRY PATTERNS AND SCALING IN NATURE AND SOCIETY

    The purpose of this work is to study the memory effect analysis of Caputo–Fabrizio time fractional diffusion equation by means of cubic B-spline functions. The Caputo–Fabrizio interpretation of fractional derivative involves a non-singular kernel that permits to describe some class of material heterogeneities and the effect of memory more effectively. The proposed numerical technique relies on finite difference approach and cubic B-spline functions for discretization along temporal and spatial grids, respectively. To ensure that the error does not amplify during computational process, stability analysis is performed. The described algorithm is second-order convergent along time and space directions. The computational competence of the scheme is tested through some numerical examples. The results reveal that the current scheme is reasonably efficient and reliable to be used for solving the subject problem.

  • Mercury content in beetroot and beetroot-based dietary supplements
    • Joanna Brzezińska-Rojek
    • Małgorzata Rutkowska
    • Justyna Ośko
    • Piotr Konieczka
    • Magdalena Prokopowicz
    • Małgorzata Grembecka
    2022 Pełny tekst JOURNAL OF FOOD COMPOSITION AND ANALYSIS

    Total mercury (THg) concentrations in fifty-four beetroot-based DSs and seven lots of conventional and organic beetroots (divided into unpeeled, peeled, and skins) were determined by direct thermal decomposition-gold amalgamation cold vapour atomic absorption spectrometry. The analytical procedure was optimised and validated. The recovery (%) for Hg was 101.9 and 92.73 in BCR-463 and DOLT 4, respectively. The intermediate precision value (4.7%) exceeded the repeatability value, which was as expected. The estimated LOD and LOQ values of the analytical procedure used were 0.096 and 0.29 [ng], respectively, and were converted to corresponding MDL and MQL values, which were 0.96 and 2.9 [ng/g], respectively. The highest contents of THg were found in conventional (28.03 ng/100 g w.w.) and organic (56.2 ng/100 g w.w.) beetroot or powder supplements (0.65 ng/g). Statistical analysis confirmed the differentiation of the analysed group of products at the level of significance 0.05 and 0.001. There were found statistically significant relationships in terms of: dietary supplement-beetroot (p < 0.001), beetroot-part of vegetable (p < 0.05) and dietary supplement-pharmaceutical form (p < 0.05). In conclusion, the analysed DSs did not pose a significant risk for a consumer in terms of permissible contamination limit, Provisional Tolerable Weekly Intake realisation, and the Target Hazard Quotient.

  • Metal nanoparticles-assisted early diagnosis of diseases
    • Maryam Jouyandeh
    • S. Mohammad Sajadi
    • Farzad Seidi
    • Sajjad Habibzadeh
    • Muhammad Tajammal Munir
    • Otman Abida
    • Sepideh Ahmadi
    • Daria Kowalkowska-Zedler
    • Navid Rabiee
    • Mohammad Rabiee
    • Golnaz Heidari
    • Mahnaz Hassanpour
    • Ehsan Nazarzadeh Zare
    • Mohammad Saeb
    2022 Pełny tekst OpenNano

    Early diagnosis is essential for the effective illness treatment, but traditional diagnostic approaches inevitably have major downsides. Recent advancements in nanoparticle-based biosensors have created new opportunities for accelerating diagnosis. High surface area, exceptional sensitivity, high specificity, and optical characteristics of metal and metal oxide nanoparticles have made it possible to detect a variety of health conditions and diseases immediately, including cancer, viral infection, biomarkers, and in-vivo imaging. Metal nanoparticles may be produced in a variety of ways, enabling the creation of innovative tools for chemical and biological sensing targets. The utilization of various metal nano-formulations, metal oxide nanoplatforms, and their composites in the early identification of illnesses is reported and summarized in this review. Additionally, the challenging corners in the use of metal oxide-based nano-scale diagnostic technologies in clinical applications are highlighted. The current work is believed to serve as a roadmap for in-depth research on inorganic nanomedicine, both in-vitro and in-vivo diagnosis of diseases and illnesses, especially pandemic infections like COVID-19.

  • Metal-organic frameworks (MOF) based heat transfer: A comprehensive review
    • Mehdi Moayed Mohseni
    • Maryam Jouyandeh
    • S. Mohammad Sajadi
    • Aleksander Hejna
    • Sajjad Habibzadeh
    • Ahmad Mohaddespour
    • Navid Rabiee
    • Hossein Daneshgar
    • Omid Akhavan
    • Mohsen Asadnia
    • Mohammad Rabiee
    • Seeram Ramakrishna
    • Rafael Luque
    • Mohammad Reza Saeb
    2022 CHEMICAL ENGINEERING JOURNAL

    Higher than a standard level, the humidity provides a suitable environment for the pathogenic microorganisms to grow and increases energy consumption for cooling, increasing greenhouse gas emissions. Desiccant air-conditioning (DAC) is an effective method to reduce humidity and energy simultaneously. Conventional desiccants are not suitable for use as a desiccant in building air conditioners, mainly because of high regeneration temperature and other issues such as limited equilibrium capacity and hydrothermal and cyclic instability. Metal-organic frameworks (MOFs) are a novel class of porous crystalline materials without the disadvantages of traditional desiccants. They benefit from a huge surface area and considerable pore-volume, very low framework density, and a high-water uptake capacity. In this review article, we have critically and comprehensively discussed the use of MOFs in heat transformation and air conditioning processes. The reasons for the superiority of MOFs over traditional desiccant materials are also discussed comprehensively. Moreover, since thermal conductivity is a key factor in the heat transfer process, an overview has been made on techniques of measuring the thermal conductivity of MOFs. Eventually, several state-of-the-art MOF-based heat transformation applications are reviewed, including heat storage, heat pumps and different desiccant dehumidifiers.

  • Metal-Organic Frameworks-Based Sensors for the Detection of Toxins in Food: A Critical Mini-Review on the Applications and Mechanisms
    • Xiaoxu Xuan
    • Mengjie Wang
    • Sivakumar Manickam
    • Grzegorz Boczkaj
    • Joon Yong Yoon
    • Xun Sun
    2022 Pełny tekst Frontiers in Bioengineering and Biotechnology

    Using scientific technologies to detect toxins in food is significant to prevent food safety problems and protect people’s health. Recently, the rise of sensors has made rapid, efficient, and safe detection of food toxins possible. One of the key factors impacting the sensor’s performance is the nanomaterials employed. Metal-organic frameworks (MOFs), with high specific surface area, tunable composition, porous structure, and flexible properties, have aroused the interest of researchers. The applications of MOFs in detecting food toxins have seen remarkable success in the past few years. In this critical mini-review, the impact of various synthesis methods on MOFs’ properties is first presented. Then, the applications and mechanisms of MOFs-based sensors in detecting various toxins are summarized and analyzed. Finally, future perspectives, potential opportunities, and challenges in this field are discussed.

  • Method of Monitoring of the Grinding Process with Lapping Kinematics Using Audible Sound Analysis
    • Mariusz Deja
    2022 Pełny tekst Journal of Machine Engineering

    Utilising microphones as audible sound sensors for monitoring a single-side grinding process with lapping kinematics is presented in the paper. The audible sound generated during grinding depended on the cutting properties of electroplated tools with D107 diamond grains and different thicknesses of the nickel bond. The tool wear affected the obtained technological effects such as material removal rate and the surface roughness of Al2O3 ceramic samples. The relationship between the quantities that characterise the sound signal and the surface roughness of machined surfaces was examined with the use of spectral analysis of the sound signal in the frequency domain with a focus on the Ra parameter. The decreasing amplitude indicated a better surface finish, down to Ra = 0.23 µm. The developed method and the obtained results will facilitate the practical use of the electroplated tools in the lap-grinding technology without interrupting the process before obtaining the required surface roughness.

  • Method of reconstructing two-dimensional velocity fields on the basis of temperature field values measured with a thermal imaging camera
    • Krzysztof Tesch
    • Michał Ryms
    • Witold Lewandowski
    2022 Pełny tekst INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER

    This paper describes a novel numerical reconstruction procedure (NRP) of the velocity field during natural convective heat transfer from a two-sided, isothermal, heated vertical plate based only on the known temperature field obtained, e.g. with a thermal imaging camera. It has been demonstrated that with a knowledge of temperature distributions, the NRP enables the reconstruction of velocity fields by solving the Navier-Stokes equation with an additional momentum source term that replaces the Fourier-Kirchhoff equation. This is because its role is played by the known temperature field, which is the equivalent of its solution. Experimental tests were performed in the air on a symmetrically heated, double-sided, isothermal vertical plate with dimensions of 150 x 75 x 2.1 mm. In this test we used a thermal imaging camera with a temperature field detector in the form of a mesh parallel to the gravity acceleration vector, perpendicular to the heating surface and adjacent to the plate in the middle of its width. It was demonstrated that with a temperature field in the form of a results matrix, such reconstruction was possible and that the results obtained were consistent with other experimental results reported elsewhere and with SNC. Along with recreating the velocity field using a standard numerical calculation (SNC), the temperature distributions and velocity fields of the plate under consideration were carried out in parallel and then compared with thermal imaging camera temperature measurements (CTM) and a reconstructed velocity field (NRP).

  • Methods for biomaterials printing: A short review and perspective
    • Hanieh Shokrani
    • Amirhossein Shokrani
    • Mohammad Saeb
    2022 Pełny tekst METHODS

    Printing technologies have opened larger windows of innovation and creativity to biomaterials engineers by providing them with the ability to fabricate complex shapes in a reasonable time, cost, and weight. However, there has always been a trouble with function adjusting in printing technologies in view of the multiplicity of materials and apparatus parameters. 3D printing, also known as additive manufacturing, revolutionized biomaterials engineering by the conversion of a digital subject into a printed object (implants, scaffolds, or diagnostics and drug delivery devices/systems). Inspired by the lessons learned from 3D printing, the concept of 4D printing (better called shape-morphing fabrication) was conceptualized and put into practice to reply on the need for responsiveness of the printed platforms to a stimulus (light, pH, temperature, voltage, humidity, etc.) in a programmable manner. Later, the next milestone in printing technology was reached by 5D printing, by which the desired objects could be printed from five axes compared to the upward one-point printing by 3D printers. 5D printers use ≈20-30% fewer materials comparatively, enabling the printing of curved surfaces. Nevertheless, all bioprinters need a bio-ink with qualified characteristics for the biomedical applications. Thus, we discussed briefly the cell viability, scaffold biomimicry, scaffold biodegradation and affordability.

  • Methods of deep modification of low-bearing soil for the foundation of new and spare air runways
    • Eligiusz Mieloszyk
    • Anita Milewska
    • Mariusz Wyroślak
    2022 Pełny tekst Przegląd Komunikacyjny

    After analyzing the impact of aircraft on the airport pavement (parking spaces, runways, startways), it was considered advisable to consider the problem of deep improvement or strengthening of its subsoil. This is especially true for low-bearing soil. The paper presents a quick and effective method of strengthening the subsoil intended for the construction of engineering structures used for civil or military air operations. It allows the use of wastelands, wetlands, swamps, etc. for the above-mentioned purposes, thus creating a dispersed network of landing sites increasing the security of the country and increasing the availability of air transport for large society groups.

  • Methylene Blue Near-Infrared Fluorescence Imaging in Breast Cancer Sentinel Node Biopsy
    • Oliver Budner
    • Tomasz Cwalinski
    • Jarosław Skokowski
    • Luigi Marano
    • Luca Resca
    • Natalia Cwalina
    • Leszek Kalinowski
    • Richelle Hoveling
    • Franco Roviello
    • Karol Polom
    2022 Pełny tekst Cancers

    Introduction: Fluorescence-based navigation for breast cancer sentinel node biopsy is a novel method that uses indocyanine green as a fluorophore. However, methylene blue (MB) also has some fluorescent properties. This study is the first in a clinical series presenting the possible use of MB as a fluorescent dye for the identification of sentinel nodes in breast sentinel node biopsy. Material and methods: Forty-nine patients with breast cancer who underwent sentinel node biopsy procedures were enrolled in the study. All patients underwent standard simultaneous injection of nanocolloid and MB. We visualized and assessed the sentinel nodes and the lymphatic channels transcutaneously, with and without fluorescence, and calculated the signal-to-background ratio (SBR). We also analyzed the corresponding fluorescence intensity of various dilutions of MB. Results: In twenty-three patients (46.9%), the location of the sentinel node, or the end of the lymphatic path, was visible transcutaneously. The median SBR for transcutaneous sentinel node location was 1.69 (range 1.66–4.35). Lymphatic channels were visible under fluorescence in 14 patients (28.6%) prior to visualization by the naked eye, with an average SBR of 2.01 (range 1.14–5.6). The sentinel node was visible under fluorescence in 25 patients (51%). The median SBR for sentinel node visualization with MB fluorescence was 2.54 (range 1.34–6.86). Sentinel nodes were visualized faster under fluorescence during sentinel node preparation. Factors associated with the rate of visualization included diabetes (p = 0.001), neoadjuvant chemotherapy (p = 0.003), and multifocality (p = 0.004). The best fluorescence was obtained using 40 M (0.0128 mg/mL) MB, but we also observed a clinically relevant dilution range between 20 M (0.0064 mg/mL) and 100 M (0.032 mg/mL). Conclusions: For the first time, we propose the clinical usage of MB as a fluorophore for fluorescence-guided sentinel node biopsy in breast cancer patients. The quenching effect of the dye may be the reason for its poor detection rate. Our analysis of different concentrations of MB suggests a need for a detailed clinical analysis to highlight the practical usefulness of the dye.

  • Metoda doboru sztywności zamocowania przedmiotu wielkogabarytowego w zastosowaniu do redukcji drgań podczas frezowania narzędziami wieloostrzowymi
    • Natalia Stawicka-Morawska
    2022

    Drgania, występujące podczas frezowania, wywierają negatywny wpływ na trwałość narzędzia i poszczególnych elementów obrabiarki oraz jakość obrabianej powierzchni. Jest to zjawisko niepożądane i pomimo wielu doniesień naukowych na temat dynamiki procesu frezowania, problem wciąż pozostaje nierozwiązany, szczególnie w odniesieniu do detali o dużych gabarytach. W pracy przedstawiono innowacyjną metodę redukcji drgań względnych narzędzie-przedmiot podczas frezowania podatnych przedmiotów wielkogabarytowych narzędziem wieloostrzowym. Opracowano dwa sposoby nadzorowania drgań względnych, tj. wykorzystujący wybrane techniki projektowania mechatronicznego oraz poprzez wykonanie obliczeń funkcji pracy sił skrawania na kierunku szerokości warstwy skrawanej. Potwierdzono poprawność zaproponowanego sposobu modelowania i nadzorowania poprzez przeprowadzenie symulacji komputerowych procesu frezowania dla wybranych parametrów obróbki za pomocą autorskiego oprogramowania, a także – poprzez obliczenia szacunkowe funkcji pracy sił skrawania. Otrzymane wyniki obliczeń zostały zweryfikowane podczas przemysłowych badań eksperymentalnych na portalowym centrum obróbkowym MIKROMAT 20V, w przedsiębiorstwie PHS HYDROTOR S.A. w Tucholi. Przedstawiona w pracy metoda istotnie różni się od powszechnie spotykanej w literaturze, gdyż przyjmuje się, że dominującym kierunkiem drgań jest kierunek szerokości warstw skrawanej.

  • Metoda neuronowego wyznaczania przestrzennych pól przepływów w przydźwiękowych i naddźwiękowych kanałach łopatkowych turbin parowych
    • Anna Milewska
    2022 Pełny tekst

    Niniejsza rozprawa doktorska została poświęcona opracowaniu metody neuronowego wyznaczania przestrzennych pól przepływów w okołodźwiękowych kanałach łopatkowych turbin parowych. Obiektem badań naukowych przedstawionych w kolejnych rozdziałach są dwa ostatnie stopnie części niskoprężnej turbozespołu 18K370 z wylotem ND-37. Pierwszym etapem badań była budowa numerycznego modelu przepływu pary mokrej przez analizowany układ łopatkowy. Warunki brzegowe zadano na podstawie wyników specjalistycznych pomiarów wewnątrz kadłuba turbiny przeprowadzonych przez Diagnostyka Maszyn Sp. z o.o. w jednej z polskich elektrowni, dzięki czemu wyniki obliczeń numerycznych można było potraktować jako specyficzne dane eksperymentalne do dalszych badań. Kolejnym krokiem było stworzenie bazy danych referencyjnych. W tym celu wykorzystano numeryczny model obliczeniowy bloku parowego o mocy 370 MW, utworzony w programie DIAGAR. Model został dostrojony do wyników pomiarów bloku energetycznego, dla pełnego pola pracy turbiny. Dalsze badania przeprowadzono przy użyciu języka programowania Python 3.7. Zbudowano szereg symulatorów przepływu pary na średnicy podziałowej analizowanego układu łopatkowego, bazując na powszechnie stosowanych modelach uczenia maszynowego. Kolejnym etapem była budowa neuronowego modelu przepływu dwuwymiarowego. Przyjęto strukturę sieci neuronowej w postaci perceptronu wielowarstwowego i przeanalizowano ją pod kątem liczby warstw ukrytych, liczby neuronów w poszczególnych warstwach, wielkości podzbioru danych treningowych wykorzystywanego do uczenia modelu neuronowego w pojedynczym kroku (ang. batch size) oraz liczby epok. Na bazie wybranej struktury neuronowego modelu przepływu na średnicy podziałowej stworzono symulator przestrzennego przepływu pary mokrej przez analizowany układ łopatkowy. Użyteczność zbudowanego symulatora neuronowego zobrazowano na przykładzie wybranego rzeczywistego kanału przepływowego turbiny parowej dużej mocy, przy uwzględnieniu dostępnych pomiarów obiegu oraz specjalistycznych pomiarów wewnętrznych turbiny.

  • Metoda oceny wiarygodności pomiarów wpływających na jakość diagnostyki cieplno-przepływowej w energetyce
    • Natalia Szewczuk-Krypa
    2022 Pełny tekst

    W rozprawie doktorskiej podjęto problem uwiarygodnienia pomiarów wpływających na jakość diagnostyki cieplno-przepływowej w energetyce. W pracy wykazano potrzebę rzetelnej informacji pozyskanej po przez pomiar parametrów, która jest niezbędna dla przeprowadzenia diagnozy badanego systemu. Jednocześnie zwrócono uwagę na zmienny charakter pracy systemów energetycznych, która wpływa na niestabilność pozyskanych danych, co prowadzi do zwiększenia niepewności pomiarowych badanych parametrów i może stać się źródłem potencjalnych błędów w ocenie systemu. W celu określenia rzetelności informacji pozyskanej z pomiarów cieplno-przepływowych zaproponowano metodę oceny wiarygodności wielkości parametrów mierzonych systemu przemian energetycznych elektrowni kondensacyjnej. W przedstawionej metodzie zastosowano rozmyty system wnioskujący, który stworzono w oparciu o klasyczne, statystyczne podejście do oceny jakości pomiaru. Poza algorytmami logiki rozmytej (ang. fuzzy logic) wykorzystano również algorytm k-średnich (ang. C-means), w celu zapewnienia uniwersalności zaproponowanego rozwiązani. Zastosowano także algorytm A priori aby wskazać zależności między parametrami badanego systemu, co pozwoliło na pełną ocenę rzetelności danych pomiarowych. W rozprawie doktorskiej wykazano, że zaproponowana metoda pozwala na efektywną, obiektywną oraz rzetelną ocenę danych pomiarowych badanego systemu. Wykazano również uniwersalność metody, która odpowiednio dostrojona może zostać wykorzystana do oceny wiarygodności pomiarów pozyskanych nie tylko z bloków energetycznych, ale także innych obiektów przemysłowych.

  • Metoda opracowania uniwersalnej osnowy na bazie krzemionki do unieruchomienia cieczy jonowych jako materiałów sorpcyjnych w technice mikroekstrakcji do fazy stacjonarnej
    • Karolina Delińska
    2022 Pełny tekst

    Rozprawa doktorska stanowi opis badań prowadzonych w trakcie czterech lat (2018-2022) studiów doktoranckich. Rezultaty prac badawczych zostały opublikowane w postaci pięciu oryginalnych artykułów, stanowiących podstawę tej rozprawy. Tematyka badań dotyczy wykorzystania cieczy jonowych w technice mikroekstrakcji do fazy stacjonarnej (ang. SPME). Głównym celem prowadzonych prac badawczych było: (a) otrzymanie nowej, porowatej sorpcyjnej powłoki włókna na bazie krzemionki, (b) unieruchomienie w porach otrzymanych materiałów cieczy jonowej oraz (c) wykorzystanie włókien w procesie ekstrakcji wybranych grup analitów z próbek wodnych oraz żywności. W toku prowadzonych prac opracowano nowy materiał sorpcyjny na bazie krzemionki, z odpowiednio dobranym prekursorem oraz substancją porotwórczą. Otrzymany materiał sorpcyjny charakteryzował się wysoką trwałością chemiczną, termiczną i mechaniczną. Włókna SPME na bazie opracowanych materiałów porowatych zostały z powodzeniem zastosowane w izolacji lotnych oraz średnio-lotnych związków organicznych. Anality, które zostały wykorzystane w przeprowadzonych badaniach obejmowały związki z grupy pochodnych benzenu oraz insektycydów organofosforowych. Z wykorzystaniem otrzymanych włókien przeprowadzono procedurę optymalizacji warunków prowadzenia ekstrakcji z fazy nadpowierzchniowej badanych próbek. Właściwości ekstrakcyjne opracowanych włókien porównano z właściwościami włókien komercyjnych. Analiza uzyskanych wyników wykazała, że opracowany materiał sorpcyjny, w przypadku wybranych analitów w próbkach wodnych żywnościowych oraz żywności, może stanowić rzeczywistą alternatywę wobec rozwiązań komercyjnych.

  • Metody analizy wytrzymałości konstrukcji wykonanych za pomocą technologii przyrostowej FDM i ich zastosowanie do warunków pracy przekładek okien podwodnych
    • Krzysztof Bobrowski
    2022 Pełny tekst

    Drukowanie 3D to technologia wytwarzania fizycznego obiektu poprzez nanoszenie kolejnych warstw materiału. W pracy zaprezentowano szereg badań eksperymentalnych i numerycznych, mających na celu zbadanie wpływu ułożenia włókien wydruku na jego własności mechaniczne. Analiza otrzymanych wyników prowadzi do wniosku, że wytrzymałość wydruku uzależniona jest od wielu parametrów druku, takich jak wysokość warstwy, kąt ułożenia włókien, orientacja wydruku w przestrzeni drukarki. Opracowano 3 modele numeryczne wydruków. Na szczególną uwagę zasługuje innowacyjny sposób budowy modelu belkowego bazującego na idei metody sztywnych elementów skończonych (SES). Przeprowadzona analiza g-codu oraz struktury wypełnienia wydruku 3D pozwala na jego bezpośrednią konwersję w liniowy model geometryczny. Poprawność modeli numerycznych została potwierdzona walidacją modeli numerycznych z badaniami eksperymentalnymi. W aspekcie aplikacyjnym, sprawdzono możliwość zastosowania metody FDM jako technologii do produkcji przekładek stosowanych w oknach podwodnych. Przeprowadzone w ramach pracy badania potwierdziły dużą zbieżność pomiędzy modelami numerycznymi i badaniami eksperymentalnymi przeprowadzonymi na obiektach materialnych. Przeprowadzona analiza numeryczna wykazała, że najlepszym materiałem na przekładki pod względem wytrzymałości doraźnej szkła są wydruki 3D.

  • Metody ekstrakcji ustrukturalizowanej treści z Wikipedii
    • Jarosław Kuchta
    2022

    Wikipedia jest od dawna przedmiotem zainteresowania badaczy. Jednym z obszarów zainteresowania jest pozyskiwanie wiedzy z treści Wikipedii a to wymaga parsowania tekstu artykułów. W tym rozdziale przedstawiono analizę porównawczą różnych możliwości parsowania treści Wikipedii, wskazując problemy, z jakimi muszą się mierzyć autorzy parserów. Dzięki temu można zrozumieć, dlaczego proces wydobywania wiedzy z Wikipedii jest trudny

  • Metody metagenomiczne w badaniu mikrobiomu jelitowego człowieka
    • Bartosz Ostrowski
    • Beata Krawczyk
    2022 Pełny tekst

    Mikroorganizmy zamieszkujące ciało człowieka to nie tylko komensale i groźne patogeny, ale także organizmy symbiotyczne pełniące kluczową rolę w zachowaniu homeostazy gospodarza. Badania metagenomiczne wykorzystujące techniki sekwen-cjonowania nowej generacji i metody bioinformatyczne pozwalają na dogłębne po-znanie mikrobiomu ludzkiego i poszukiwanie jego związku ze stanem zdrowia czło-wieka. Celem pracy jest omówienie różnych metodologii badawczych stosowanych w poznaniu mikrobiota jelitowej, począwszy od klasycznych metod hodowlanych, mikrobiologicznego profilowania opartego o analizę sekwencyjną zakonserwowanego ewolucyjnie genu markerowego (np. wysokoprzepustowe sekwencjonowanie oparte o gen 16S rDNA jest uważane jako złoty standard w badaniu mikrobiota), aż po właściwą analizę metagenomiczną typu shotgun, opartą o sekwencjonowanie nowej generacji (NGS – ang. next-generation sequencing).

  • Metody poprawy skuteczności oczyszczania powietrza zanieczyszczonego hydrofobowymi lotnymi związkami organicznymi w biofiltrach ze złożem zraszanym
    • Piotr Rybarczyk
    • Bartosz Szulczyński
    • Dominik Dobrzyniewski
    • Jacek Gębicki
    2022

    Zanieczyszczenie powietrza atmosferycznego lotnymi związkami organicznymi o charakterze odorowym stanowi uciążliwy problem środowiskowy oraz społeczny. Do oczyszczania dużych objętości tego typu gazów stosuje się m.in. biofiltrację. W niniejszej pracy przedyskutowano główne trudności związane z oczyszczaniem powietrza zanieczyszczonego hydrofobowymi lotnymi związkami organicznymi oraz podano aktualne trendy poprawy skuteczności oczyszczania ww. strumieni w procesach biofiltracji.

  • Metody wgłębnej mody$ kacji gruntu słabonośnego do posadowienia nowych i zapasowych lotniczych dróg startowych.
    • Eligiusz Mieloszyk
    • Anita Milewska
    • Mariusz Wyroślak
    2022 Pełny tekst Przegląd Komunikacyjny

    Po analizie oddziaływań statków powietrznych na nawierzchnię lotniska (miejsca postojowe, pasy startowe, drogi startowe) uznano za celowe rozważenie problemu wgłębnego ulepszania lub wzmacniania podłoża gruntowego. Dotyczy to szczególnie gruntu sła- bonośnego. Przedstawiono szybką i skuteczną metodę wzmacniania podłoża gruntowego przeznaczonego do budowy obiektów inżynier- skich wykorzystywanych do wykonywania cywilnych lub wojskowych operacji lotniczych. Pozwala ona wykorzystywać do wspomnianych celów nieużytki, tereny podmokłe, bagna itp. tworząc w ten sposób rozproszoną sieć lądowisk zwiększającą bezpieczeństwo kraju oraz zdynamizować dostępność do transportu lotniczego dużych grup społecznych.

  • Metodyka testowania paliw żeglugowych w rzeczywistych warunkach pracy silnika o zapłonie samoczynnym.
    • Zbigniew Korczewski
    2022

    W monografii zestawiono opracowane metody diagnozowania silnika o zapłonie samoczynnym dużej mocy, które umożliwiają dokonanie kompleksowej oceny jakości użytkowej zastosowanego paliwa zasilającego pod względem energetycznym, emisyjnym i strukturalnym (niezawodnościowym). Przybliżono wybrane aspekty organizacyjne i metrologiczne testowania standardowych i modyfikowanych paliw żeglugowych w warunkach laboratoryjnych. Tego typu badania realizowane na modelu fizycznym w małej skali bezpośrednio poprzedzają wdrożenie testowanego paliwa do zasilania pełnowymiarowych silników okrętowych w eksploatacji. W początkowej części opracowania przedstawiono obszerną charakterystykę zaprojektowanej i zbudowanej instalacji zasilania paliwem silnika badawczego, która odwzorowuje adekwatne cechy konstrukcyjne i procesowe (parametryczne) rzeczywistej instalacji okrętowej. Uwzględniono w niej – między innymi – konieczność oczyszczania i podgrzewania paliwa przed jego wprowadzeniem do komory spalania silnika. Zaprezentowano również schemat organizacji badań przy zastosowaniu odpowiednio skonfigurowanej aparatury pomiarowej (diagnostycznej). Kluczowe znaczenie ma rozdział 4 poświęcony metodzie tworzenia rankingu jakości użytkowej paliw żeglugowych, którą opracowano zgodnie z teorią badań operacyjnych. Przyjęta procedura testowania paliwa przewiduje sformułowanie wielokryterialnej oceny jego przydatności eksploatacyjnej na podstawie badań eksperymentalnych procesów energetycznych silnika o zapłonie samoczynnym w ściśle określonych stanach obciążenia – ustalonych i nieustalonych. Badaniu poddaje się również emisyjność chemiczną spalin wylotowych, a także zmiany stanu technicznego przestrzeni roboczej oraz aparatury 164 Streszczenie w języku polskim wtryskowej silnika spowodowane destrukcyjnym oddziaływaniem testowanego paliwa zasilającego. Rozdział 6, będąc integralną częścią monografii, stanowi jednocześnie jej największy walor utylitarny, gdyż w odróżnieniu od wcześniejszych treści, stricte laboratoryjnych, zawiera szczegółowe wskazówki metodyczne odnośnie do realizacji badań energetycznych i emisyjnych silnika okrętowego w eksploatacji, zasilanego jednym z paliw żeglugowych testowanych wcześniej na silniku badawczym w laboratorium. Wyniki systematycznie prowadzonych badań eksploatacyjnych silnika objętego nadzorem diagnostycznym potwierdziły wysoką jakość użytkową zastosowanego paliwa, dobrze prognozując trwałość i niezawodność zasilanych nim silników okrętowych.

  • MgPdSb─An Electron-Deficient Half-Heusler Phase
    • Michał Winiarski
    • Kamila Stolecka
    • Leszek Litzbarski
    • Thao Tran
    • Karolina Górnicka
    • Tomasz Klimczuk
    2022 Pełny tekst Journal of Physical Chemistry C

    The half-Heusler family consists of many semiconducting intermetallic compounds, virtually all of them having a valence electron count (VEC) of 18. We have studied an electron-deficient (VEC = 17) phase MgPdSb and its Pd-stuffed variant MgPd1.25Sb. The cubic F4̅3m crystal structure was confirmed by the Rietveld refinement of powder X-ray diffraction (XRD) data. The lattice parameter is a = 6.284 and 6.335 Å for MgPdSb and MgPd1.25Sb, respectively. The Debye temperature and Sommerfeld coefficient for MgPdSb are ΘD = 282 K and γ = 3.3 mJ mol–1 K–2, respectively, and are similar to those obtained for MgPd1.25Sb. There is neither phase transition nor superconductivity observed above 1.8 K. The differences between the electronic structures of Mg-based half-Heusler compounds make them robustly metallic, irrespective of the electron count and the introduction of interstitial transition metal (Pd) atoms.

  • Microbial and chemical quality assessment of the small rivers entering the South Baltic. Part II: Case study on the watercourses in the Puck Bay catchment area
    • Emilia Bączkowska
    • Agnieszka Kalinowska
    • Oskar Ronda
    • Katarzyna Jankowska
    • Rafał Bray
    • Bartosz Płóciennik
    • Żaneta Polkowska
    2022 Pełny tekst Archives of Environmental Protection

    Due to its location, Puck Bay is an area particularly vulnerable to pollution of anthropogenic origin. The aim of the study was to assess the water quality of small watercourses entering the inner part of Puck Bay. The paper presents the results of chemical and microbiological analyses of 10 rivers and canals at their estuaries located on the western shore of the internal Puck Bay. The following environmental parameters were analyzed: conductivity, pH, dissolved oxygen concentration (in situ measurements), COD (cuvette tests), concentrations of ions (ion chromatography). Microbiological analysis included assessment of sanitary condition based on the number of fecal coliforms by a cultivation method. The determination of basic microbiological parameters such as: prokaryotic cell abundance expressed as total cells number (TCN), prokaryotic cell biovolume expressed as average cell volume (ACV), the prokaryotic biomass (PB) and prokaryotic cell morphotype diversity were determined using epifluorescence microscopy method. Based on the obtained results, it was found that small watercourses may carry a notable load of anthropogenic pollution and thus affect the environment of Puck Bay. The results clearly indicate the need for quality monitoring in the rivers and canals in the Coastal Landscape Park, flowing into Puck Bay. The research showed that also smaller watercourses may have an impact on the coastal waters’ state, and thus on the Baltic Sea water quality.

  • Microbial fuel cell applications for removal of petroleum hydrocarbon pollutants: A review
    • Pegah Fatehbasharzad
    • Samira Aliasghari
    • Ipak Shaterzadeh Tabrizi
    • Javed Khan
    • Grzegorz Boczkaj
    2022 Pełny tekst Water Resources and Industry

    Bioelectrochemical systems (BESs) are considered as the potential approaches to remediate the environments contaminated by hydrocarbons. This review addresses the application of BESs particularly microbial fuel cells (MFCs) in degradation of petroleum hydrocarbons, including BTEXs, from soil, water, wastewater and sediments. Details on reactor design and critical issues are discussed. Aspects on electrodes, redox mediators and membranes are evaluated, including economic feasibility. The microbial community is considered in detail. It can be concluded, that comparing to classic configurations, single-chamber air-cathode reactors are more cost-effective. Secondly, systems based on small-scale units are recommended for future developments.

  • Microcrystalline diamond film evaluation by spectroscopic optical coherence tomography
    • Paulina Strąkowska
    • Marcin Strąkowski
    2022 Pełny tekst Photonics Letters of Poland

    This study has focused on the microcrystalline diamond film (MCD) thickness evaluation. For this purpose, optical coherence tomography (OCT) enhanced by spectroscopic analysis has been used as a method of choice. The average thickness of the tested layer was about 1.5 µm, which is below the standard 2-point OCT resolution. In this case, the usefulness of the spectroscopic analysis was confirmed for the evaluation of the thickness changes in the submicrometer range.

  • Microfluidic devices for photo-and spectroelectrochemical applications
    • Robert Bogdanowicz
    • Martin Jönsson-Niedziolka
    • Elizaveta Vereshchagina
    • Anna Dettlaff
    • Suchanat Boonkaew
    • Mattia Pierpaoli
    • Paul Wittendorp
    • Shruti Jain
    • Frode Tyholdt
    • Jacob Thomas
    • Pawel Wojcik
    2022 Pełny tekst Current Opinion in Electrochemistry

    The review presents recent developments in electrochemical devices for photo- and spectroelectrochemical investigations, with the emphasis on miniaturization (i.e., nanointerdigitated complementary metal-oxide-semiconductor devices, micro- and nano-porous silicon membranes or microoptoelectromechanical systems), silica glass/microreactors (i.e., plasmonic, Raman spectroscopy or optical microcavities) or polymer-based devices (i.e., 3D-printed, laser-engraved channels). Furthermore, we have evaluated inter alia the efficiency of various fabrication approaches for bioelectrochemical systems, biocatalysis, photochemical synthesis, or single nanoparticle spectroelectrochemistry. We envisioned the miniaturization of applied techniques such as cathodoluminescence, surface plasmon resonance, surface-enhanced Raman spectroscopy, voltametric and amperometric methods in the spectroelectrochemical microdevices. The research challenges and development perspectives of microfluidic, and spectroelectrochemical devices were also elaborated on.

  • Microporous N-Doped Carbon Obtained from Salt Melt Pyrolysis of Chitosan toward Supercapacitor and Oxygen Reduction Catalysts
    • Maria Rybarczyk
    • Karolina Cysewska
    • Recep Yuksel
    • Marek Lieder
    2022 Pełny tekst Nanomaterials

    The direct carbonization of low-cost and abundant chitosan biopolymer in the presencesalt eutectics leads to highly microporous, N-doped nanostructures. The microporous structureeasily manufactured using eutectic mixture (ZnCl2 -KCl) and chitosan. Potassium ions here can act as an intercalating agent, leading to the formation of lamellar carbon sheets, whereas zinc chloride generates significant porosity. Here, we present an efficient synthetic way for microporous carbon nanostructures production with a total nitrogen content of 8.7%. Preliminary studies were performed to show the possibility of the use of such material as a catalyst for supercapacitor and ORR. The textural properties enhanced capacitance, which stem from improved accessibility of previously blocked or inactive pores in the carbon structure, leading to the conclusion that porogen salts and molten salt strategies produce materials with tailor-made morphologies. The synergistic effectthe eutectic salt is seen in controlled porous structures and pore size, and the micropores boosting adsorption ability.

  • Microwave Alignment and Displacement Sensors in Groove Gap Waveguide Technology
    • Ali Karami Horestani
    • Zahra Shaterian
    • Michał Mrozowski
    2022

    This paper is aimed at presenting highly sensitive microwave displacement and alignment sensors. With this goal, the method of realizing mechanically tunable cavity resonators in groove gap waveguides technology is presented. The resonance frequency of the cavity is then used for displacement sensing. It is also demonstrated that the symmetry properties of a pair of groove gap waveguide cavities can be used to improve the robustness of the sensor to variations in ambient conditions. The proposed sensor also benefits from a reference zero, thus can be used as an alignment sensor. A very good sensitivity of S=1.25 GHz/mm is achieved, which can be easily improved by scaling the operating frequency.

  • Microwave Characterization of Dielectric Sheets in a Plano-Concave Fabry-Perot Open Resonator
    • Bartlomiej Salski
    • Tomasz Karpisz
    • Małgorzata Warecka
    • Piotr Kowalczyk
    • Piotr Czekala
    • Pawel Kopyt
    2022 IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES

    Despite its long history, a double-concave (DC) Fabry-Perot open resonator (FPOR) has recently gained popularity in the characterization of dielectrics in the 20–110 GHz range, mainly due to such novel accomplishments as full automation of the measurement process and the development of even ore accurate and computationally efficient electromagnetic model. However, it has been discovered that such a DC resonator suffers from unwanted mode coupling present for electrically thick samples. Such limitations are missing in a plano-concave (PC) FPOR. For those reasons, the aim in this article is to apply the newly proposed scattering matrix method in the study of major properties of that kind of a resonator and, subsequently, to propose a new tool dedicated to the measurement of dielectrics without the aforementioned limits. For the first time in the literature, major properties of the PC FPOR with and without the sample, such as resonance frequencies, geometric factors, energy filling factors, and the resulting quality factor, are rigorously computed. Moreover, their impact on the accuracy of the loss tangent extraction is investigated. Such a study, which opens the way for accurate microwave characterization of electrically thick dielectric sheets above 20 GHz, has never been performed before. The whole complex permittivity extraction algorithm presented in this article is validated experimentally by measuring wellknown materials, namely, C-plane sapphire, silicon, and Z-cut monocrystalline quartz.

  • Microwave Ring Resonator Based Pressure Sensor
    • Abhishek Kumar Jha
    • Michał Mrozowski
    2022

    This paper demonstrates a microwave pressure sensor, which is based on microstrip line-fed ring resonators. The first ring resonator is loaded with the concentric cylindrical shafts, while the same number of the hollow shanks as the shafts are mounted on the second ring resonator. The arrangement of the cylindrical shaft and hollow shank allows for mechanical movement between two substrates while maintaining electrical contact. The external pressure applied to the substrate translates the cylindrical shaft into the hollow shank, resulting in a change in the resonant frequency. The proposed sensor is found to measure an applied pressure up to 40.5 kPa with an average sensitivity of 9.62 kHz/Pa.