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  • Brief Literature Review and Classification System of Reliability Methods for Evaluating the Stability of Earth Slopes
    • Jarosław Przewłócki
    2021 Pełny tekst Sustainability

    The issue of slope stability is one of the most important and yet most difficult geotechnical problems. Assessing slope stability is particularly difficult because of the many uncertainties involved in the process. To take these uncertainties into account, probabilistic methods are used, and the reliability approach is adopted. There are many methods for reliability assessment of earth slope stability. However, there is no system that would organize all of these methods in an unambiguous way. In fact, these methods can be classified in different ways: by assignment to a deterministic classification of methods, by description of uncertainties of soil parameters, by level of reliability according to the theory of reliability, etc. The huge number of articles summarizing the research in this field, but in various “disordered” directions, certainly do not facilitate the understanding or ultimately the practical application of the reliability approach by the engineer. The paper proposes a universal classification system of reliability methods for evaluating the stability of earth slopes. This proposal is preceded by a brief literature review of both historical background and contemporary research on reliability analysis of earth slope stability.

  • Budowanie strategii edukacyjnej uczelni z uwzględnieniem wykorzystania e-technologii – wnioski z analizy doświadczeń uczelni technicznej
    • Anita Dąbrowicz-Tlałka
    • Magdalena Musielak
    2021 Pełny tekst Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej

    Artykuł zawiera wnioski z podsumowania działań koncepcyjnych i organizacyjnych jakie zostały przeprowadzone w toku rozbudowy uczelnianej platformy edukacyjnej i jej integracji z systemami uczelni. Autorki podjęły starania, aby na podstawie analizowanego przypadku uczelni technicznej, przedstawić rekomendacje związane z tworzeniem edukacyjnej strategii uczelni w zakresie zdalnej edukacji. W artykule przedstawiono dane z ankiet oraz dane dotyczące systemów edukacyjnych Politechniki Gdańskiej, które uzyskano w okresie zawieszenia kształcenia na uczelniach.

  • Burnout Investigation of Small Diameter Tubes Immersed in Nanofluids
    • Janusz Cieśliński
    • Katarzyna Ronewicz
    2021 Pełny tekst ENERGIES

    This paper deals with research into pool boiling critical heat flux (CHF) of water–Al2O3, water–TiO2 and water–Cu nanofluids on horizontal stainless steel tubes. The experiments were conducted under atmospheric pressure. Nanoparticles were tested at concentrations of 0.001%, 0.01%, 0.1% and 1% by weight. Ultrasonic vibration was used in order to stabilize the dispersion of the nanoparticles. Although dispersants were not used to stabilize the suspension, the solutions tested showed satisfactory stability. Experimental measurements were performed with stainless steel tubes of three outside diameters: 1.6, 3 and 5 mm. Enhancement of CHF was observed to be independent of the concentration and material of the nanoparticles and tube diameter, with simultaneous heat transfer degradation. Built up during the boiling process, nanolayers improve substantially the heating surface wettability. A correlation is suggested for the CHF prediction during pool boiling of nanofluids.

  • Business continuity management framework for Industry 4.0 companies regarding dependability and security of the ICT and ICS/SCADA system
    • Kazimierz Kosmowski
    2021 Pełny tekst

    This chapter addresses a business continuity management (BCM) framework for the Industry 4.0 companies including the organizational and technical solutions, regarding the dependability and security of the information and telecommunication technology (ICT), and the industrial control system (ICS) / supervisory control and data acquisition (SCADA) system. These technologies and systems play nowadays important roles in modern advanced manufacturing systems and process plants due to their openness to external systems and networks using various communication channels. It gives on the one hand, some advantages in effective realization of technological and business processes, logistics and distribution of goods, but, on the other hand, makes the company assets and resources potentially vulnerable to some threats with relevant risks. The chapter outlines some ideas related to designing a business continuity management system (BCMS) based on defined processes and procedures. Such system includes planning of changes in organization / industrial company, nonconformity issues, and planning corrective actions. In a final part of this chapter the leadership importance, and staff awareness and responsibility are emphasized to create a robust and healthy corporate culture based on accepted values, properly spread among the employees. It is beneficial for shaping good organizational culture, and then safety and security culture. The BCM approach outlined in this chapter distinguishes both preventive and recovery activities regarding suggestions in selected international standards and domain publications.

  • Buzz-based honeybee colony fingerprint
    • Tymoteusz Cejrowski
    • Julian Szymański
    2021 Pełny tekst COMPUTERS AND ELECTRONICS IN AGRICULTURE

    Non-intrusive remote monitoring has its applications in a variety of areas. For industrial surveillance case, devices are capable of detecting anomalies that may threaten machine operation. Similarly, agricultural monitoring devices are used to supervise livestock or provide higher yields. Modern IoT devices are often coupled with Machine Learning models, which provide valuable insights into device operation. However, the data preparation step for ML models has to be addressed differently for industrial and agriculture cases. Animals are characterized by their circadian rhythms and seasonal dependence, which can bias the accuracy of classifiers. In the presented work, a Design-of-Experiment (DoA) approach for extracting valuable bee colony audio data is described. With the presented methods, it is possible to precisely define the most distinctive bee hours where unique colony sounds are emitted. The first step of the data filtering process is based on identifying the ambient temperatures that are conducive to its operation. The second step provides the unique hours specification based on the hives’ characteristics comparison where dissimilar time periods are being marked. For this comparison, the most noticeable difference between the colonies is calculated with MSE integral and thus the trend’s joint component is removed. A new concept of a bees’ fingerprint was introduced for the identification of the particular bee colony.

  • Bypass kolejowy dla wiaduktu łukowego i kratownicowego w ciągu modernizowanej linii kolejowej E59 na odcinku Wronki – Dobiegniew
    • Agnieszka Makowska
    • Cezary Najda
    • Anna Banaś
    2021 Mosty

    W artykule przedstawiono realizacje bypassu kolejowego, zlokalizowanego nieopodal miejscowości Krzyż Wielkopolski w ciągu linii kolejowej E59 na skrzyżowaniu z linią kolejową 203. Wariantowa analiza kilku zaproponowanych rozwiązań wykazała, ze wykonstruowanie bypassu na czas prowadzenia prac modernizacyjnych pozwoli na utrzymanie ciągłości ruchu kolejowego, nie stworzy nadmiernych problemów podróżnym, a jednocześnie pozwoli na obniżenie kosztów inwestycji w stosunku do wdrożenia komunikacji zastępczej.

  • By-Products from Food Industry as a Promising Alternative for the Conventional Fillers for Wood–Polymer Composites
    • Aleksander Hejna
    • Jerzy Korol
    • Paulina Kosmela
    • Anton Kuzmin
    • Adam Piasecki
    • Arkadiusz Kulawik
    • Błażej Chmielnicki
    2021 Pełny tekst Polymers

    The present paper describes the application of two types of food-industry by-products, brewers’ spent grain (BSG), and coffee silverskin (ŁK) as promising alternatives for the conventional beech wood flour (WF) for wood–polymer composites. The main goal was to investigate the impact of partial and complete WF substitution by BSG and ŁK on the processing, structure, physicochemical, mechanical, and thermal properties of resulting composites. Such modifications enabled significant enhancement of the melt flowability, which could noticeably increase the processing throughput. Replacement of WF with BSG and ŁK improved the ductility of composites, which affected their strength however. Such an effect was attributed to the differences in chemical composition of fillers, particularly the presence of proteins and lipids, which acted as plasticizers. Composites containing food-industry by-products were also characterized by the lower thermal stability compared to conventional WF. Nevertheless, the onset of decomposition exceeding 215 ◦C guarantees a safe processing window for polyethylene-based materials.

  • Cable-stayed bridges. Basic static schemes
    • Krzysztof Żółtowski
    2021 Pełny tekst Archives of Civil Engineering

    The paper presents an overview of shaping of cable-stayed bridges. Historical background, basic static sketches and overview of selected bridges are included. Selected natural solutions and interesting unrealized projects were presented. Basic ideas and most important principals are discussed. The examples and sketches were given an author's comment. Static diagrams of two pylon structures with three variants of the arrangement of cables are presented. The details important for the structure were discussed and the consequences of choosing the variant were indicated. Mono-pylon structures in asymmetric and symmetrical arrangements are shown. the solutions are discussed and the details important for the structure are indicated. An overview of multi-pylon structures is also presented, paying attention to important details. All the discussed static diagrams were enriched with realized examples. The advantages and disadvantages of individual structural solutions are presented. The main ideas allowing to achieve the goal in the implementation of non-standard suspended structures were also indicated.

  • Calibration-Free Single-Anchor Indoor Localization Using an ESPAR Antenna
    • Mateusz Groth
    • Krzysztof Nyka
    • Łukasz Kulas
    2021 Pełny tekst SENSORS

    In this paper, we present a novel, low-cost approach to indoor localization that is capable of performing localization processes in real indoor environments and does not require calibration or recalibration procedures. To this end, we propose a single-anchor architecture and design based on an electronically steerable parasitic array radiator (ESPAR) antenna and Nordic Semiconductor nRF52840 utilizing Bluetooth Low Energy (BLE) protocol. The proposed algorithm relies on received signal strength (RSS) values measured by the receiver equipped with the ESPAR antenna for every considered antenna radiation pattern. The calibration-free concept is achieved by using inexpensive BLE nodes installed in known positions on the walls of the test room and acting as reference nodes for the positioning algorithm. Measurements performed in the indoor environment show that the proposed approach can successfully provide positioning results better than those previously reported for single-anchor ESPAR antenna localization systems employing the classical fingerprinting method and relying on time-consuming calibration procedures.

  • Can bottom sediments be a prospective fertilizing material? A chemical composition analysis for potential reuse in agriculture.
    • Karolina Matej-Łukowicz
    • Ewa Wojciechowska
    • Joanna Strycharz
    • Marta Szubska
    • Karol Kuliński
    • Jacek Bełdowski
    • Aleksandra Winogradow
    2021 Pełny tekst Materials

    Every year huge amounts of bottom sediments are extracted worldwide, which need to be dis-posed. The recycling of bottom sediments for soil fertilization is in line with the long-promoted circular economy policy and enables the use of micro and macronutrients accumulated in sedi-ments for soil fertilization. When considering potential agricultural reuse of the dredge sediments, the first necessary step should be to analyze whether the heavy metal content meets the obligatory criteria. Then, the contents of valuable elements required for plant growth and their ratios should be assessed. In this study, the content of nitrogen, organic carbon, phosphorus and potassium was tested and iron, sulfur, calcium and magnesium were also analysed along vertical profiles of sed-iments extracted from 4 urban retention tanks in Gdańsk (Poland). The sediments were indicated to have a low content of nutrients (Ntot 0.01-0.52%, Corg 0.1-8.4%, P₂O₅ 0.00-0.65%, K 0.0-1.0%) while being quite rich in Fe and S (0.2-3.3%, 0.0-2.5% respectively). The C/N ratio changed in the range of 17.4-28.4, which proved good nitrogen availability for plants. The mean values of the Fe/P ratio were above 2.0, which confirms that phosphorus in the sediments would be available to the plants in the form of iron phosphate. To sum up, the bottom sediments from municipal reten-tion reservoirs are not a perfect material for soil fertilization, but they are a free waste material which, when enriched with little cost, can become a good fertilizer. Future research should focus on cultivation experiments with the use of sediments enriched with N, P, Corg.

  • Can the Pandemic Be a Catalyst of Spatial Changes Leading Towards the Smart City?
    • Barbara Zgórska
    • Dorota Kamrowska-Załuska
    • Piotr Lorens
    2021 Pełny tekst Urban Planning

    The worldwide spread of Covid‐19 infections has had a pervasive influence on cities and the lives of their residents. The current crisis has highlighted many urban problems, including those related to the functionality of urban structures, which directly affect the quality of life. Concurrently, the notion of “smart cities” is becoming a dominant trend in the discourse on urban development. At the intersection of these two phenomena, questions about the effects of Covid‐19 on the future of cities arise. These are concerned with the possible roles of the pandemic in the process of urban regeneration and the development of smart solutions. The article aims to create a conceptual framework that will allow researchers to assess the influence of Covid‐19‐related changes on urban structures and their functionality in the following areas: city structure, connectivity and mobility, public spaces, access to green areas, and digital transformation. In the empirical part of the article, the influence of pandemic‐caused changes on the development of various aspects of smart cities is discussed. The article concludes with an analysis of the effects the pandemic might have on digital urban regeneration

  • Can Web Search Queries Predict Prices Change on the Real Estate Market?
    • Nina Rizun
    • Anna Baj-Rogowska
    2021 Pełny tekst IEEE Access

    This study aims to explore whether the intensity of internet searches, according to the Google Trends search volume index (SVI), is a predictor of changes in real estate prices. The motivation of this study is the possibility to extend the understanding of the extra predictive power of Google search engine query volume of future housing price change (shift direction) by (i) the introduction of a research approach that combines the advantages of the complementary use of cross-correlation analysis and machine learning classification algorithms; (ii) applying the multi-class HPI values classifier which allows predicting the housing price increase, decrease or relative stability; (iii) exploiting the SVI that relates to interests in both ‘real estate’ and ‘credit to buy real estate’; (iv) evaluation of the introduced approach in the context of the Polish real estate market. The main theoretical contribution of our work is a confirmation that the freely available information regarding Google user searches can provide an in-depth insight into enriching the generally accepted statistics on supply and demand in the real estate market. From the practical perspective, this research confirms that SVI can be associated as a sole determinant to anticipate the housing price change with time-lag sufficient for making decisions regarding the purchase (sale) of individual property or the real estate market control. Such findings can be also helpful for researchers who intend to use Google Trends data as an extra variable from demand side to improve the prediction accuracy if it is included in the model which is based on the existing housing prices determinants.

  • CaO-based high temperature CO2 sorbents – Literature review
    • Donata Konopacka-Łyskawa
    • Natalia Czaplicka
    • Andrzej Szefer
    2021 Pełny tekst Chemical and Process Engineering : New Frontiers

    The use of CaO-based adsorbents has a high potential to capture CO2 from various systems due to its high reactivity with CO2, high capacity, and low cost of naturally derived CaO. The application of CaO-based sorbents to remove carbon dioxide is based on a reversible reaction between CaO and CO2. However, multiple carbonation/calcination cycles lead to a rapid reduction in the sorption capacity of natural CaO, and therefore efforts are made to reduce this disadvantage by doping, regenerating, or producing synthetic CaO with stable sorption properties. In this review, the synthesis methods used to obtain CaO-based sorbents were collected, and the latest research on improving their sorption properties was presented. The most commonly used models to describe the CO2 sorption kinetics on CaO-based sorbents were also introduced. The methods of sorbent regeneration and their effectiveness were summarized. In the last part of this review, the current state of advancement of work on the larger scale, possible problems, and opportunities during scale-up of the calcium looping process were presented. Concluding (i) the presented methods of adsorbent synthesis allow for the production of doped CaO adsorbents on a laboratory scale, characterized by high CO2 capture efficiency and good cyclic stability, (ii) the most commonly used in practice models describing CO2 chemisorption are empirical models and the shrinking core model, (iii) the use of sorbent regeneration allows for a significant improvement in sorption capacity, (iv) the scale-up of both the production of new CaO adsorbents and the CO2 capture technology with their use requires further development.

  • Carbon nanoarchitectures as high-performance electrodes for the electrochemical oxidation of landfill leachate
    • Mattia Pierpaoli
    • Paweł Jakóbczyk
    • Mirosław Sawczak
    • Aneta Łuczkiewicz
    • Sylwia Fudala-Książek
    • Robert Bogdanowicz
    2021 Pełny tekst JOURNAL OF HAZARDOUS MATERIALS

    Nanomaterials and assemblies of the aforementioned into complex architectures constitute an opportunity to design efficient and selective solutions to wide spread and emerging environmental issues. The limited disposal of organic matter in modern landfills generates extremely concentrated leachates characterised by high concentrations of refractory compounds. Conventional biochemical treatment methods are unsuitable, while advanced treatment, such coagulation, reverse osmosis and ultrafiltration can be very costly and generate additional waste. Electrochemical oxidation is an established technique to efficiently mineralise a plethora of recalcitrant pollutants, however the selectivity and efficiency of the process are strongly related to the anode material. For this reason, a nanoarchitectured carbon material has been designed and synthesised to improve the capability of the anode towards the adsorption and decomposition of pollutants. Instead of simple nanostructures, intelligently engineered nanomaterials can come in handy for more efficient advanced treatment techniques. In this study, a carbon nanoarchitecture comprising boron-doped vertically aligned graphene walls (BCNWs) were grown on a boron-doped diamond (BDD) interfacial layer. The results show how the peculiar maze-like morphology and the concurrence of different carbon hybridisations resulted in a higher current exchange density. The BDD performed better for the removal of NH4+ while the BCNW-only sample exhibited a faster deactivation. The BDD/BCNW nanoarchitecture resulted in an enhanced COD removal and a NH4+ removal similar to that of BDD, without the intermediate production of NO2− and NO3−.

  • Cascade Object Detection and Remote Sensing Object Detection Method Based on Trainable Activation Function
    • S. N. Shivappriya
    • M. Jasmine Pemeena Priyadarsini
    • Andrzej Stateczny
    • C. Puttamadappa
    • B. D. Parameshachari
    2021 Pełny tekst Remote Sensing

    Object detection is an important process in surveillance system to locate objects and it is considered as major application in computer vision. The Convolution Neural Network (CNN) based models have been developed by many researchers for object detection to achieve higher performance. However, existing models have some limitations such as overfitting problem and lower efficiency in small object detection. Object detection in remote sensing hasthe limitations of low efficiency in detecting small object and the existing methods have poor localization. Cascade Object Detection methods have been applied to increase the learning process of the detection model. In this research, the Additive Activation Function (AAF) is applied in a Faster Region based CNN (RCNN) for object detection. The proposed AAF-Faster RCNN method has the advantage of better convergence and clear bounding variance. The Fourier Series and Linear Combination of activation function are used to update the loss function. The Microsoft (MS) COCO datasets and Pascal VOC 2007/2012 are used to evaluate the performance of the AAF-Faster RCNN model. The proposed AAF-Faster RCNN is also analyzed for small object detection in the benchmark dataset. The analysis shows that the proposed AAF-Faster RCNN model has higher efficiency than state-of-art Pay Attention to Them (PAT) model in object detection. To evaluate the performance of AAF-Faster RCNN method of object detection in remote sensing, the NWPU VHR-10 remote sensing data set is used to test the proposed method. The AAF-Faster RCNN model has mean Average Precision (mAP) of 83.1% and existing PAT-SSD512 method has the 81.7%mAP in Pascal VOC 2007 dataset.

  • Case study of water vapour transmission properties of EPDM façade membranes
    • Andrzej Ambroziak
    • Sławomir Dobrowolski
    2021 Pełny tekst Archives of Civil Engineering

    This research aimed to investigate the water vapour transmission properties of chosen EPDM membranes applied in façade and window systems under laboratory tests. The applied procedure included in national and international standards utilized for the laboratory tests of water vapour transmission properties of EPDM membrane is described. Two main types (outside and inside types) of EPDM membranes are laboratory tested. The authors indicated that the EPDM membranes should differ in surface factures. Nevertheless, some manufacturers mark EPDM membranes on each roll (on the package only) without different permanent denotations on the EPDM membranes surfaces. This form of denotations can cause using problems-using the wrong types of the EPDM aprons in building partitions, because when the package is removed there is impossible to visually identify the type of EPDM membrane (outside or inside type) from the texture of the membrane surface. The experimental results of laboratory tests indicated using the wrong type of EPDM membrane in the inside aprons in building partitions in the investigated façade window system. The designed proportion of the sd values (the resistance to movement of water vapour) of inside and outside EPDM façade membranes should be designed equally to about 3.0 (recommended value 4) to provide proper diffusion properties of partitions around windows in façade systems. The paper can provide scientists, engineers, and designers an experimental basis in the field of the EPDM membranes water vapour transmission properties applied to façades and windows systems.

  • Cassirer E. Język i mit. Przyczynek do zagadnienia imion bogów.Przekład, wstęp i opracowanie: Przemysław Parszutowicz.. Wydaw. Marek Drzewiecki,2021
    • Przemysław Parszutowicz
    2021

    Rozprawa Cassirera pochodzi z najważniejszego bodaj okresu jego twórczości – okresu współpracy z Biblioteką Warburga – i mimo niewielkich rozmiarów jest w dużej mierze reprezentatywna, tak gdy idzie o wykorzystywaną przez niego metodę, jak i o główny obszar jego zainteresowań badawczych. Stanowi bezpośrednie nawiązanie do rozprawy Hermanna Usenera Götternamen. Versuch einer Lehre von der religiösen Begriffsbildung. Pod względem swojej treści książka przedstawia silną korelację języka i mitu, słowa i magii, biorąc za punkt wyjścia twierdzenie o zasadniczej zgodności istoty bóstwa z jego imieniem. Opisuje przykłady sprawczej siły słowa w świecie opanowanym przez myślenie mityczne i przez to wskazuje na zasady i swoistą „logikę” mitu. Język przedstawia tutaj to, co myślenie mityczne bezpośrednio wyraża: odzwierciedlenie całości w każdym szczególe, przyczynowość opartą na celowym działaniu jakiegoś podmiotu, a zatem uduchowienie i personifikację przyrody, oparcie na zmysłowym, bezpośrednim oglądzie, na bezpośredniej zmysłowej obecności.

  • CEL FUNKCJONOWANIA, ZADANIA I OBSZARY BADAWCZE CENTRUM MORSKIEJ ENERGETYKI WIATROWEJ POLITECHNIKI GDAŃSKIEJ
    • Zbigniew Korczewski
    2021 Pełny tekst Journal of Polish CIMEEAC

    W artykule przybliżono wybrane aspekty funkcjonowania Centrum Morskiej Energetyki Wiatrowej w Politechnice Gdańskiej. Scharakteryzowano główne zadania Centrum oraz wstępnie zdefiniowane obszary badawcze, w których specjalizują się naukowcy reprezentujący niemal wszystkie wydziały akademickie Uczelni (oprócz Wydziału Architektury). Przedstawiono kierunki działania Centrum w perspektywie kilku najbliższych lat, w wyniku których nastąpi weryfikacja i konieczne doprecyzowanie obszarów badawczych, zgodnie z oczekiwaniami inwestorów morskich farm wiatrowych budowanych w polskiej wyłącznie strefie ekonomicznej Morza Bałtyckiego.

  • Cellulosic bionanocomposites based on acrylonitrile butadiene rubber and Cuscuta reflexa: adjusting structure-properties balance for higher performance
    • Midhun Dominic C.D.
    • Rani Joseph
    • P.M. Sabura Begum
    • Athira S Kumar
    • P. A. Jeemol
    • Thomasukutty Jose
    • Dileep Padmanabhan
    • Krzysztof Formela
    • Suchart Siengchin
    • Jyotishkumar Parameswaranpillai
    • Mohammad Saeb
    2021 CELLULOSE

    Design and manufacture of cellulosic nanocomposites with acceptable performance is in the period of a transition from fantasy to reality. Typically, cellulosic nanofillers reveal poor compatibility with polymer matrices. Thus, adjusting the balance between structure and properties of cellulosic bionanocomposites by careful selection of parent ingredients is the first priority. Herein, we incorporated Cuscuta reflexa derived cellulose nanofibers (CNFs) into acrylonitrile-butadiene rubber (NBR) for high-performance elastomeric applications. Tensile and tear strength of NBR improved by ~ 125 and ~ 105 %, respectively at a very low loading of 4 phr CNFs, as a result of interfacial bonding, as evidenced by fractographic analysis. In parallel, the temperature at which maximum degradation occurs (Tmax) of NBR rose by 14 °C. The swelling index and molar uptake of toluene were also lowered. The Wolff-activity coefficient, hardness, abrasion resistance, and cross-link density were all improved correspondingly. The positive shift in glass transition temperature and the fall in the loss tangent peak height for bionanocomposites proved the effective immobilization of NBR chains by well-dispersed CNFs. The hydrogen bonding interaction between –OH groups of CNFs and –CN groups of NBR might be responsible for the superior performance of NBR/CNF composites, which is confirmed by Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction analysis (XRD).

  • Cement kiln dust
    • Hakim S. Abdelgader
    • Mugahed Amran
    • Marzena Kurpińska
    • Mohammad Mosaberpanah
    • Gunasekaran Murali
    • Roman Fediuk
    2021

    The volume of cement production in the world has remained at the level of approxi mately 4.1 billion tons/year. The cement production process is energy intensive and is the world’s leading emitter of carbon dioxide. Therefore, the main activities cement plants are aimed at introducing technologies changes in production of clinkier.The construction industry is responsible for the majority of CO2 emissions to the atmosphere: the industry emits 30% of total CO2, building emits 28%, transportation is responsible for 22% of CO2, the production of building materials causes 11% of CO2 emissions, including the cement industry is responsible for around 7% of emissions CO2. Other industries are responsible for around 9% of CO2 emissions to the atmosphere. The process of burning raw materials for the production of clinker is the most important stage of the entire cement production process. Cement kiln dust (CKD) is waste generated during the production of clinker. The dust collected in the dust collectors is partly reused in the production process and some is stored. The storage method is not preferred due to its operations negative en vironmental impact. If the dust contains alkalis, chlorides, sulphates, or heavy metals, they cannot be recycled. Generally cement plants strive to reduce the formation of dust. About 1.5 tons of raw materials are used to produce 1 ton of clinker. After the extraction, grinding, and homogenization of raw materials, the process of calcination of calcium carbonate takes place. The source of calcium carbonate is naturally occurring limestone deposits, namely limestone, marl, or chalk. Then, to obtain clinker, calcium oxide is sintered with silica, aluminum oxide, and iron oxide at a temperature of 1450°C. Most often, clinker is fired using the dry or wet method in a long rotary kiln. After firing, the clinker is ground together with the binding regulator - gypsum and additives. To generate the heat needed to burn the clinker, fossil fuels such as petcoke, hard coal, lignite, and fuel oil or natural gas are used. Due to proecological activities, secondary solid fuels are used as alternative fuels as substitutes for fossil fuels. The amount of thermal energy obtained from their combustion currently accounts for about 85% of the total amount of thermal energy used in the clinker burning process. These changes lead to effective energy management through the efficient use of natural and alternative fuels.

  • Cerclage cable augmentation does not increase stability of the fixation of intertrochanteric fractures. A biomechanical study
    • Marcin Ceynowa
    • Krzysztof Żerdzicki
    • Paweł Kłosowski
    • Rafał Pankowski
    • Marek Rocławski
    • Tomasz Mazurek
    2021 Orthopaedics & Traumatology-Surgery & Research

    Background: Intertrochanteric fractures with a posteromedial intermediate fragment are unstable because of the loss of medial support. Additional fixation with a cerclage is used in subtrochanteric fractures, but not in intertrochanteric fractures. The aim of this biomechanical study is to evaluate whether cerclage fixation improves stability of intertrochanteric fractures. Hypothesis: Our hypothesis is that the cerclage fixation of the intermediate fragment increases fixation stability of intertrochanteric fractures.Materials and methods: Synthetic femora with intertrochanteric fractures (AO 31.A1.3) with a posteromedial fragment were fixed with a long gamma nail. The intermediate fragment was fixed with a cerclage cable. Four groups were compared: 1: no cable fixation; 2: anatomic reduction and cable fixation; 3:anatomic reduction and fixation of a fragment where its proximal part was removed simulating comminution; 4: non-anatomic reduction and cable fixation. The specimens were loaded axially in a testing machine. The preload was 100 N, followed by ten conditioning cycles from 100 N to 500 N. The test phase consisted of the cyclic loading between 100 N and the maximum force that increased at a rate of 50 N at each cycle until failure. The stiffness was calculated from the load/displacement curve of the last three conditioning cycles.Results: There were no statistically significant differences between force to failure (group 1: 681 N; group2: 846 N; group 3: 699 N; group 4: 806 N; ANOVA p = 0.23) and stiffness (group 1: 769 N/mm; group2: 819 N/mm; group 3: 815 N/mm; group 4: 810 N/mm; ANOVA p = 0.84) between groups. There were significant differences in the widening of the lag screw canal (group 1: 2.16 mm; group 2: 4.5 mm; group3: 3 mm; group 4: 2.5 mm; ANOVA p = 0.017). In individual comparison, the differences were significant only between the anatomical reduction group and the non-anatomical reduction (p = 0.04) and the no cable group (p = 0.02).Discussion: There is a controversy in clinical literature whether cable fixation improves treatment outcome of proximal femoral fractures. This study suggests that medial wall reconstruction with a cerclage cable does not improve axial stability of the fixation. Level of evidence: Not applicable; a biomechanical study.

  • CFD Simulations and Tests of a Prototype Flow Control Valve
    • Marta Zaleska-Patrosz
    • Piotr Patrosz
    • Paweł Śliwiński
    2021 Pełny tekst

    In this paper a prototype of a flow control valve is described and numerically simulated. The flow control valve is used in hydraulic systems to maintain constant fluid flow despite changing loads of a receiver. The standard construction of this type of valves is modified mainly by eliminating the spring. The prototype consists the hydrostatically unloaded throttle valve and pressure ratio valve substituting pressure difference valve. The article concentrates on numerical simulation conducted for different positions of pressure ratio valve’s spool and various throttle valve settings. Additionally the rotation of the spool is included in simulation and its influence on valve’s characteristics is evaluated. The article also describes the methodology of determining flow characteristics of control valve. Results from numerical simulation are compared to results of experimental research.

  • CFFT columns in road through railroad crossings
    • Eligiusz Mieloszyk
    • Anita Milewska
    • Marcin Abramski
    2021

    There were 12801 road through railroad one-level crossings in Poland in 2018. 215 accidents happened at them in 2018. In order to increase safety in rail and road traffic two-level crossings should be used. They are definitely safer and make the traffic more smooth. In the design and construction of two-level intersections of railway and road or path columns of circular cross-section are often used. They can be successfully replaced by CFFT columns (Concrete-Filled (Fibre-Reinforced Polymer) Tube). The advantage of CFFT columns is the possibility of their widespread use. As the research of these columns shows, including those conducted at the Gdansk University of Technology, they can carry significant compressive loads by their relatively small cross-section. They are resistant to corrosion and protect against corrosion concrete and its reinforcement (if used). In addition, it is worth adding that the electrical resistance of FRP composite is greater than 1GΩ, which is particularly important in the case of electrified railway lines or tram lines.

  • Chain Action - How Do Countries Add Value Through Digital Government?
    • Jaromir Durkiewicz
    • Tomasz Janowski
    2021 Pełny tekst

    This study examineshow countries develop and benefit from Digital Government(DG).The literature proposes various conceptualizations of the value-adding logic of DG, but the benchmarking practice is not respondingto such proposals.For instance, the United Nations’E-Government Surveycombines the readiness and uptake indicatorsand failsto cover any impactindicators;thus,its diagnostic valueis limited. To overcome this limitation, weintroduce a new assessment schemebased on the DG value chain conceptand pursue the question: how do the world countries add value in this chain?Reassembling the UN’s e-Government Survey indicatorsand the World Bank’s Worldwide Governance Indicators,we examine how the 191 UN Member States converted their readiness into uptakeanduptake into impactover the 2014-2018 period. The results rank the countries concerning their performance alongthe DG value chain, identify hotspots, and calculatethe value chain performance of regional and economic groups.

  • Challenges and opportunities related to the use of sewage sludge ash in cement-based building materials – A review
    • Lesław Świerczek
    • Bartłomiej Cieślik
    • Piotr Konieczka
    2021 Pełny tekst JOURNAL OF CLEANER PRODUCTION

    Due to the increasingly demanding legal regulations, regarding both sewage sludge (SS) and solid residues obtained during its thermal utilization processes, new solutions to limit their negative impact on the environment are sought. One approach that eliminates the risk of sewage sludge ash (SSA) is its use in cement building materials. The article contains a detailed literature review regarding the use of SSA in mortars and concretes, where it is defined as the addition or substitute of the main binder. The issues of the impact of SSA quality (CaO content, the share of pozzolanic oxides, their ratio) on cement products are discussed in details. In addition to the description of the mechanical properties of building materials, the SSA impact on parameters such as workability, shrinkage of products and setting time is also described. It can be stated that using SSA in building industry is one of the most ecological approaches of SSA managing. Due to the toxic nature of SSA, data on the leaching of heavy metals from hardened mortar or concrete samples are presented to emphasize the contaminants immobilization effectiveness by cement products. Based on the analysis of the data presented in the article, solutions that can reduce the negative consequences of including SSA in building materials have been identified. However, due to the significant differences in SS thermal utilization technologic and SS characteristics, every SSA should be thoroughly characterized before implementing the most suitable stabilization/solidification methods

  • Challenges associated with development of AUV - unmanned autonomous underwater vehicles to be operated using the AI-based control systems
    • Mirosław Gerigk
    • Mateusz Gerigk
    2021 Per mare ad astra

    The last decade has been devoted towards further development of the UUV unmanned underwater vehicles which may be of two types. There are the USV unmanned surface vehicles and UUV unmanned underwater vehicles. There is a growing interest to work out and implement the fully advanced AUV autonomous underwater vehicles. The main drivers towards development of such the vehicles are the technologies of autonomous systems, sensors and effectors, innovative materials including the nano-materials and "intelligent" materials, innovative energy supply sources, innovative propulsion systems combining the efficient and silent both the engines and propellers, innovative IT technologies including the double mode air-underwater control, navigation and communication systems. The additional set of features the AUV vehicles may possess are the stealth-based and bio-technology-based solutions. The commercial applications of AUV vehicles may perform the conventional patrol and reconnaissance tasks. The navy devoted AUV vehicles may enable to perform the reconnaissance and combat missions. Despite of applications it is necessary to implement the advanced on-board hardware and software solutions to provide the high level of autonomy to the AUV vehicles. The general requirements to obtain an autonomous AUV vehicle are concentrated on the autonomy from the energy supply, self-control and self-navigation point of view. It may be associated with using no-communication with the centre of mission. Such the level of autonomy requires the innovative solutions concerning the vehicle's sensors, effectors and control. The biggest challenge associated with the AUV vehicles development is to work out and implement a kind of an intelligent AUV vehicle. A major difficulty to obtain such the vehicle is to acquire the precise data from the surrounding environment, to process these data and to use them to perform all the tasks and mission in real time domain. The AUV-AI-based vehicle should be equipped with a kind a mini-brain to compare the on-board simulated virtual reality with the reality outside the vehicle due to activity of sensors, mini-brain control system and effectors. Such the on-line comparison may enable to obtain the expected functionality, performance and safety of the AUV-AI-based vehicle for the benefit of mission.

  • Changes in Epigenetic Patterns Related to DNA Replication in Vicia faba Root Meristem Cells under Cadmium-Induced Stress Conditions
    • Aneta Żabka
    • Natalia Gocek
    • Konrad Winnicki
    • Paweł Szczeblewski
    • Tomasz Laskowski
    • Justyna Polit
    2021 Pełny tekst Cells

    Experiments on Vicia faba root meristem cells exposed to 150 µM cadmium chloride (CdCl2) were undertaken to analyse epigenetic changes, mainly with respect to DNA replication stress. Histone modifications examined by means of immunofluorescence labeling included: (1) acetylation of histone H3 on lysine 56 (H3K56Ac), involved in transcription, S phase, and response to DNA damage during DNA biosynthesis; (2) dimethylation of histone H3 on lysine 79 (H3K79Me2), correlated with the replication initiation; (3) phosphorylation of histone H3 on threonine 45 (H3T45Ph), engaged in DNA synthesis and apoptosis. Moreover, immunostaining using specific antibodies against 5-MetC-modified DNA was used to determine the level of DNA methylation. A significant decrease in the level of H3K79Me2, noted in all phases of the CdCl2-treated interphase cell nuclei, was found to correspond with: (1) an increase in the mean number of intranuclear foci of H3K56Ac histones (observed mainly in S-phase), (2) a plethora of nuclear and nucleolar labeling patterns (combined with a general decrease in H3T45Ph), and (3) a decrease in DNA methylation. All these changes correlate well with a general viewpoint that DNA modifications and post-translational histone modifications play an important role in gene expression and plant development under cadmium-induced stress conditions.

  • Changes on the Surface of the SiO2/C Composite, Leading to the Formation of Conductive Carbon Structures with Complex Nature of DC Conductivity
    • Piotr Okoczuk
    • Marcin Łapiński
    • Tadeusz Miruszewski
    • Piotr Kupracz
    • Leszek Wicikowski
    2021 Pełny tekst Materials

    Sol–gel layers have been the subject of many studies in recent decades. However, very little information exists about layers in which carbon structures are developed in situ. Using the spin-coating method, we obtained thin iron-doped SiO2/C composite films. The results of Raman spectroscopy showed that our samples consisted of graphitic forms and polymers. The latter’s contribution decreases with rising temperature. FTIR and EDS studies show changes in carbon distribution on top of the layer, depending on the sintering temperature. The samples sintered at 800 C showed a significant increase in the contribution of carbon forms to the layer’s surface. Therefore, high conductivity can be observed in this sample. The results of XPS spectroscopy showed that the contribution of sp3 hybridized carbon increases after etching. The total electrical conductivity, studied by a DC four-wire technique, increased with the temperature and showed almost linear characteristics with significant changes below 150 K. The reduced activation energy plot has a positive temperature coefficient, which is a characteristic property of the conductive polymers in a metallic regime of conductivity.

  • Channel State Estimation in LTE-Based Heterogenous Networks Using Deep Learning
    • Krzysztof Cwalina
    • Piotr Rajchowski
    • Alicja Olejniczak
    • Olga Błaszkiewicz
    • Robert Burczyk
    2021 Pełny tekst SENSORS

    Following the continuous development of the information technology, the concept of dense urban networks has evolved as well. The powerful tools, like machine learning, break new ground in smart network and interface design. In this paper the concept of using deep learning for estimating the radio channel parameters of the LTE (Long Term Evolution) radio interface is presented. It was proved that the deep learning approach provides a significant gain (almost 40%) with 10.7% compared to the linear model with the lowest RMSE (Root Mean Squared Error) 17.01%. The solution can be adopted as a part of the data allocation algorithm implemented in the telemetry devices equipped with the 4G radio interface, or, after the adjustment, the NB-IoT (Narrowband Internet of Things), to maximize the reliability of the services in harsh indoor or urban environments. Presented results also prove the existence of the inverse proportional dependence between the number of hidden layers and the number of historical samples in terms of the obtained RMSE. The increase of the historical data memory allows using models with fewer hidden layers while maintaining a comparable RMSE value for each scenario, which reduces the total computational cost.

  • Characterization and Filtration Efficiency of Sustainable PLA Fibers Obtained via a Hybrid 3D-Printed/Electrospinning Technique
    • Mattia Pierpaoli
    • Chiara Giosuè
    • Natalia Czerwińska
    • Michał Rycewicz
    • Aleksandra Wieloszyńska
    • Robert Bogdanowicz
    • Maria Letizia Ruello
    2021 Pełny tekst Materials

    The enormous world demand for personal protective equipment to face the current SARS-CoV-2 epidemic has revealed two main weaknesses. On one hand, centralized production led to an initial shortage of respirators; on the other hand, the world demand for single-use equipment has had a direct and inevitable effect on the environment. Polylactide (PLA) is a biodegradable, biocompatible, and renewable thermoplastic polyester, mainly derived from corn starch. Electrospinning is an established and reproducible method to obtain nano- and microfibrous materials with a simple apparatus, characterized by high air filtration efficiencies. In the present work, we designed and optimized an open-source electrospinning setup, easily realizable with a 3D printer and using components widely available, for the delocalized production of an efficient and sustainable particulate matter filter. Filters were realized on 3D-printed PLA support, on which PLA fibers were subsequently electrospun. NaCl aerosol filtration tests exhibited an efficiency greater than 95% for aerosol having an equivalent diameter greater than 0.3 μm and a fiber diameter comparable to the commercially available FFP2 melt-blown face mask. The particulate entrapped by the filters when operating in real environments (indoors, outdoors, and working scenario) was also investigated, as well as the amount of heavy metals potentially released into the environment after filtration activity

  • Characterization of Arctic Driftwood as Naturally Modified Material. Part 1: Machinability
    • Daniel Chuchała
    • Anna Sandak
    • Kazimierz Orłowski
    • Jakub Sandak
    • Olafur Eggertsson
    • Michał Landowski
    2021 Pełny tekst Coatings

    Arctic driftwood has reached the coast of Iceland for centuries. This material was used by the inhabitants of the island as a building material for houses, boats, churches and pasture fences. Nowadays, the driftwood is used in the furniture industry, for the finishing of internal and external walls of buildings and also by artists. The properties of driftwood differ to that of original resource due the long-term effects of exposure to Arctic Sea water and ice. This process can be considered as a natural modification, even if its effect on various wood properties and the potential use of driftwood are not yet fully understand. This research is focused on the comparison of cutting forces measured for Siberian larch (Larix sibirica L.) from Siberia provenance and driftwood found on the coast of Iceland. The cutting forces were determined directly from the cutting power signal that was recorded during the frame sawing process. A new procedure for compensation of the late/early wood ratio variation within annual rings is proposed to homogenize mechanical properties of wood. It allows a direct comparison of machinability for both types of larch wood investigated (driftwood and natural). Noticeable differences of normalized cutting force values were noticed for both wood types, which were statistically significant for two set values of feed per tooth. These results provide a new understanding of the effect of the drifting process in the Arctic Sea (natural modification) on mechanical and physical properties of wood. Such a natural modification may influence transformation processes of driftwood as well as performance of the coating systems applied on its surface.

  • Characterization of d-xylose reductase, XyrB, from Aspergillus niger
    • Agata Terebieniec
    • Tania Chroumpi
    • Adiphol Dilokpimol
    • Maria Victoria Aguilar-Pontes
    • Miia R. Mäkelä
    • Ronald de Vries
    2021 Pełny tekst Biotechnology Reports

    D-xylose reductase is a member of the aldo-keto reductase family, and is involved in D-xylose and L-arabinose conversion through the Pentose Catabolic Pathway (PCP) in fungi. In this study, we biochemically characterized a newly identified second D-xylose reductase (XyrB) from Aspergillus niger. This NADPH-dependent reductase is able to efficiently convert D-xylose and L-arabinose, and it has the highest affinity for these sugars of all currently known fungal pentose reductases. A combination of biochemical data, transcriptomics and phylogenetic analysis further illustrated the role of XyrB in the PCP.

  • Characterization of fracture process in polyolefin fibre-reinforced concrete using ultrasonic waves and digital image correlation
    • Magdalena Rucka
    • Erwin Wojtczak
    • Magdalena Knak
    • Marzena Kurpińska
    2021 Pełny tekst CONSTRUCTION AND BUILDING MATERIALS

    This study explores the monitoring of the fracture process in concrete beams and aims to characterize the evolution of damage in polyolefin fibre-reinforced concrete beams by utilizing the integrated application of two measurement techniques, digital image correlation and ultrasonic testing. The interpretation of registered wave time histories data was provided by the calculation of the magnitude-phase-composite metrics. An efficient procedure for the determination of strain field and the identification of crack height was subsequently developed. The results of the study show that the energy and phase shifts of ultrasonic waves can be used as autonomous damage indicators in a system for the real-time monitoring of a fracture process.

  • Characterization of herbal teas containing lime flowers – Tiliae flos by HPTLC method with chemometric analysis
    • Natalia Melnyk
    • Karolina A. Pawłowska
    • Maria Ziaja
    • Wojciech Wojnowski
    • Oleh Koshovyi
    • Sebastian Granica
    • Agnieszka Bazylko
    2021 FOOD CHEMISTRY

    Linden trees are a source of food products called lime flowers (Tiliae flos), traditionally used in the form of infusion for the treatment of feverish colds and coughs. Lime flowers should include flowers of Tilia cordata Mill, T.x europaea L., and T. platyphyllos Scop. or a mixture of these. The aim of current research was to establish a fast, sensitive HPTLC (high-performance thin-layer chromatography) method that would allow the differentiation of material obtained from five species of lime occurring in Europe. The fingerprints for distinguishing these species were established, as well as a key for identification based on a visual evaluation of chromatograms. The results obtained were also subjected to chemometric analyses. It was shown that each species contains characteristic compounds i.e. linarin that can be used for their identification. The method developed can, in theory, be introduced for the quality control or authentication of linden flowers on the European market.

  • Characterization of Highly Filled Glass Fiber/Carbon Fiber Polyurethane Composites with the Addition of Bio-Polyol Obtained through Biomass Liquefaction
    • Adam Olszewski
    • Paweł Nowak
    • Paulina Kosmela
    • Łukasz Piszczyk
    2021 Pełny tekst Materials

    This work aims to investigate the process of obtaining highly filled glass and carbon fiber composites. Composites were manufactured using previously obtained cellulose derived polyol, polymeric methylene diphenyl diisocyanate (pMDI). As a catalyst, dibutyltin dilaurate 95% and Dabco® 33-LV were used. It was found that the addition of carbon and glass fibers into the polymer matrix causes an increase in the mechanical properties such as impact and flexural strength, Young’s modulus, and hardness of the material. Moreover, the dynamic mechanical analysis (DMA) showed a significant increase in the material’s storage modulus and rigidity in a wide range of temperatures. The increase in glass transition of soft segments can be noticed due to the limitation of macromolecules mobility in the material. The thermogravimetric analysis showed a four step decomposition, with maximal degradation rate at TmaxII = 320–330 °C and TmaxIII = 395–405 °C, as well as a significant improvement of thermal stability. Analysis of the material structure using a scanning electron microscope showed the presence of material defects such as voids, fiber pull-outs, and agglomerates of both fibers.

  • Characterization of PVDF/Graphene Nanocomposite Membranes for Water Desalination with Enhanced Antifungal Activity
    • Emilia Gontarek-Castro
    • Maria Rybarczyk
    • Roberto Castro-Muñoz
    • Monica Morales-Jiménez
    • Blanca Barragán-Huerta
    • Marek Lieder
    2021 Pełny tekst Water

    Seawater desalination is a worldwide concern for the sustainable production of drinking water. In this regard, membrane distillation (MD) has shown the potential for effective brine treatment. However, the lack of appropriate MD membranes limits its industrial expansion since they experience fouling and wetting issues. Therefore, hydrophobic membranes are promising candidates to successfully deal with such phenomena that are typical for commercially available membranes. Here, several graphene/polyvinylidene (PVDF_G) membranes with different graphene loading (0–10 wt%) were prepared through a phase inversion method. After full characterization of the resulting membranes, the surface revealed that the well-dispersed graphene in the polymer matrix (0.33 and 0.5 wt% graphene loading) led to excellent water repellence together with a rough structure, and a large effective surface area. Importantly, antifungal activity tests of films indicated an increase in the inhibition percentage for PVDF_G membranes against the Curvularia sp. fungal strain. However, the antifungal surface properties were found to be the synergistic result of graphene toxicity and surface topography.

  • Charakterystyka genetyczna szczepów Klebsiella pneumoniae izolowanych od pacjentów po przeszczepieniu nerki oraz badanie wpływu leków immunosupresyjnych na ekspresję genów bakteryjnych
    • Magdalena Wysocka
    2021 Pełny tekst

    Bakterie z gatunku Klebsiella pneumoniae należą do oportunistycznych patogenów odpowiedzialnych za zakażenia szpitalne. Drobnoustroje te wykazują skłonność do oporności wielolekowej i wysokiej wirulencji, co stanowi poważne zagrożenie dla pacjentów nieimmunokompetentnych. Wśród pacjentów po transplantacji nerki zakażenia układu moczowego (ZUM) stanowią najczęstszą przyczynę powikłań infekcyjnych. Mechanizmy molekularne leżące u podstaw patogenezy K. pneumoniae nie są w pełni poznane. Celem pracy doktorskiej była charakterystyka genetyczna szczepów K. pneumoniae wyizolowanych od biorców nerki z ZUM lub bezobjawową bakteriurią. Zbadano wpływ leków immunosupresyjnych (tacrolimusu, cyklosporyny) na wzrost bakterii i ekspresję genów bakteryjnych istotnych w kolonizacji dróg moczowych w tej grupie chorych. Określono profile wirulencji i antybiotykooporności. Zidentyfikowano nietypowy dla ZUM fenotyp hipermukoidalny, oporność na antybiotyki β-laktamowe o rozszerzonym spektrum działania (ESBL) oraz w przypadku niektórych szczepów produkcję metalo-β-laktamazy (typ NDM-1), nadającą oporność na karbapenemy. Poprzez sekwencjonowanie (WGS) wybranych genomów wykazano obecność ruchomych elementów genetycznych istotnych w horyzontalnym transferze genów i nadających nowe cechy bakterii. Drugim z aspektów naukowych pracy było zbadanie wpływu wybranych leków immunosupresyjnych na ekspresję fimbrii typu 1. Wykazano, że rodzaj zastosowanej terapii immunosupresyjnej może mieć wpływ na rozwój infekcji dróg moczowych.

  • Charakterystyka materiałowo-technologiczna oraz proces degradacji posadzek betonowych typu lastrico
    • Sylwia Świątek-Żołyńska
    • Maciej Niedostatkiewicz
    • Władysław Ryżyński
    2021 Pełny tekst Izolacje

    W artykule przedstawiono wybrane zagadnienia materiałowe i technologiczne dotyczące posadzek typu lastrico. Opisany został proces degradacji warstwy wierzchniej posadzki lastrico. Szczególną uwagę zwrócono na wpływ specyfiki tego rodzaju posadzki na sposób oceny ich stanu technicznego.

  • Chemical hazard in glacial melt? The glacial system as a secondary source of POPs (in the Northern Hemisphere). A systematic review
    • Filip Pawlak
    • Krystyna Kozioł
    • Żaneta Polkowska
    2021 Pełny tekst SCIENCE OF THE TOTAL ENVIRONMENT

    Toxicity of compounds belonging to persistent organic pollutants (POPs) iswidely known, and their re-emission from glaciers has been conclusively demonstrated. However, the harmful effects associated with such secondary emissions have yet to be thoroughly understood, especially in the spatial and temporal context, as the existing literature has a clear sampling biaswith the best recognition of sites in the European Alps. In this review, we elaborated on the hazards associated with the rapid melting of glaciers releasing organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and polycyclic aromatic hydrocarbons (PAHs). To this end,we collated knowledge on: (1) the varying glacier melt rate across the Northern Hemisphere, (2) the content of POPs in the glacial system components, including the less represented areas, (3) the mechanisms of POPs transfer through the glacial system, including the importance of immediate emission fromsnowmelt, (4) risk assessment associatedwith POPs re-emission. Based on the limited existing information, the health risk of drinking glacial water can be considered negligible, but consuming aquatic organisms from these waters may increase the risk of cancer. Remoteness from emission sources is a leading factor in the presence of such risk, yet the Arctic is likely to be more exposed to it in the future due to large-scale processes shifting atmospheric pollution and the continuous supply of snow. For future risk monitoring,we recommend to explore the synergistic toxic effects of multiple contaminants and fill the gaps in the spatial distribution of data.

  • Chemical, Physical, and Mechanical Properties of 95-Year-Old Concrete Built-In Arch Bridge
    • Andrzej Ambroziak
    • Elżbieta Haustein
    • Maciej Niedostatkiewicz
    2021 Pełny tekst Materials

    This research aimed to determine the durability and strength of an old concrete built-in arch bridge based on selected mechanical, physical, and chemical properties of the concrete. The bridge was erected in 1925 and is located in Jagodnik (northern Poland). Cylindrical specimens were taken from the side ribs connected to the top plate using a concrete core borehole diamond drill machine. The properties of the old concrete were compared with the present and previous standard requirements and guidelines. The laboratory testing program consisted of the following set of tests: measurements of the depth of carbonated zone and dry density, water absorption tests, determination of concrete compressive strength and frost resistance, determination of modulus of elasticity, measurement of the pH value, determination of water-soluble chloride salt and sulfate ion content, and X-ray diffraction analyses. Large variations in the cylindrical compressive strength (14.9 to 22.0 MPa), modulus of elasticity (17,900 to 26,483 MPa), density (2064 to 2231 kg/m3), and water absorption (3.88 to 6.58%) were observed. In addition to the experiments, a brief literature survey relating to old concrete properties was also conducted. This paper can provide scientists, engineers, and designers an experimental basis in the field of old concrete built-in bridge construction.

  • Chemical surface etching methods for ground tire rubber as sustainable approach for environmentally-friendly composites development– a review
    • Mapoloko Mpho Phiri
    • Mohau Justice Phiri
    • Krzysztof Formela
    • Shanganyane Percy Hlangothi
    2021 Pełny tekst COMPOSITES PART B-ENGINEERING

    Ground tire rubber (GTR) has been used as a sustainable low-cost modifier in various composites. However, due to the hydrophobic nature of GTR, it is in compatible with most matrices and results in deterioration in both mechanical and physical properties of composites. This necessitates pre-modification of the powdered rubber to improve the interfacial bonding at the rubber-matric interface. The most common GTR modification research relies on surface etching via use of various techniques. The current review aims to give a detailed overview of the surface etching chemical modification methods for GTR for incorporation into various matrices such as concrete, bitumen and polymers. The review will serve as a guide for engineers, chemists and manufactures with interest of including GTR in any type of composite for achieving compatibility with the main matrix. The surface chemical etching treatment methods such as acid etching, hydroxylation, oxidation, and radiation methods are discussed in this work. The characterization methods to confirm the functional groups on the modified GTR and the effect of the treatment on the resultant GTR composites are also highlighted. Finally, this review highlights the advantages and limitations of the chemical surface etching processes for GTR.

  • Chemical Vapor Transport Route toward Black Phosphorus Nanobelts and Nanoribbons
    • Łukasz Macewicz
    • Krzysztof Pyrchla
    • Robert Bogdanowicz
    • Gamini Sumanasekera
    • Jacek B. Jasinski
    2021 Pełny tekst Journal of Physical Chemistry Letters

    Chemical vapor transport (CVT) method is widely used for bulk black phosphorus (BP) fabrication. In this work, we demonstrate that CVT provides a route for the fabrication of BP nanoribbons and nanobelts. This method consists of a two-step procedure, including initial BP column growth using the CVT technique, followed by ultrasonic treatment and centrifugation. The obtained nanostructures preserve BP column dimensions, forming ultralong ribbon-like structures with the length to the width aspect ratio of up to 500. Computational modeling of the growth mechanism of a BP flake is also presented in support of the observed columnar growth. Calculation of the average energy of the molecule in the asymmetric flakes shows that the growth of the structure in the zigzag direction is more energetically favorable than in the armchair direction.

  • Chemometrics approaches to green analytical chemistry procedure development
    • Kaja Kalinowska
    • Marta Bystrzanowska
    • Marek Tobiszewski
    2021 Pełny tekst Current Opinion in Green and Sustainable Chemistry

    Chemometric tools are widely used in analytical chemistry for the reduction of data dimensionality, grouping of variables and processing of analytical signals. They have also the potential to be applied in analytical procedure development with the aim of minimizing the procedure’s environmental impact. The design of experiment gives the possibility to obtain much better information on the system response than in case of “changing one variable at a time” approach. This results in savings of materials and energy. Desirability functions applied together with the design of experiment, create a possibility to include in procedure development the variables that directly refer to the procedure’s greenness. In this way analysis time, consumption of solvents or reagents and, mobile phase (in the case of liquid chromatography) can be minimized. Cluster analysis and principal component analysis are successfully applied to find greener solvent alternatives.

  • Chip suction system in circular sawing machine: empirical research and computational fluid dynamics numerical simulations
    • Jacek Barański
    • Przemysław Dudek
    2021 Pełny tekst ACTA FACULTATIS XYLOLOGIAE ZVOLEN

    The experimental analysis of the wood chip removing system during its redesigning in the existing sliding table circular saw and computational fluid dynamic (CFD) numerical simulations of the air flow process is presented in the paper. The attention was focused on the extraction hood and the bottom shelter of the actual existing system. The main aim was to perform experimental research on the pressure distribution inside the hood and at the exit of the bottom shelter and the air flow distribution during operation of wood chip removal system. In the work a systematic experimental study of pressure and numerical modelling of the air flow distribution in the upper cover and bottom shelter during operation for the selected rotational speed of saw blade of 3 500 and 6 000 min-1 with a diameter of  300 mm and  450 mm were carried out. The analyses of results obtained from the experimental measurements and numerical simulations allowed the estimation of the areas with improper air flow hindering the controlled transport of wood chips and to optimize the shape of extraction hood and the bottom shelter. As the result, a new design of the chip suction system was obtained, noticeably improving the chips extraction from the tool operation space.

  • Chiral Pyrazolo[4,3-e][1,2,4]triazine Sulfonamides—Their Biological Activity, Lipophilicity, Protein Affinity, and Metabolic Transformations
    • Zofia Bernat
    • Anna Mieszkowska
    • Zofia Mazerska
    • Joanna Matysiak
    • Zbigniew Karczmarzyk
    • Katarzyna Kotwica-Mojzych
    • Mariusz Mojzych
    2021 Pełny tekst Applied Sciences-Basel

    Referring to our previous laboratory results related to the tyrosinase and urease inhibition by pyrazolo[4,3-e][1,2,4]triazine sulfonamides, we examined here in silico the mechanism of action at the molecular level of the investigated pyrazolotriazine sulfonamides by the molecular docking method. The studied compounds being evaluated for their cytotoxic effect against cancer cell lines (MCF-7, K-562) and for recombinant Abl and CDK2/E kinase inhibitory potency turned out to be inactive in these tests. The pyrazolotriazines were also investigated with respect to their lipophilicity and plasma protein binding using HPLC chromatography in isocratic conditions. The observed small affinity for plasma proteins could be advantageous in the potential in vivo studies. Moreover, the compounds were sensitive to metabolic transformations with phase I enzymes, which led to the hydroxylation and dealkylation products, whereas phase II transformations did not occur.

  • Chracteristics of anaerobic ammonium oxidation initated by anaerobic granular sludge
    • Mao Hong-yu
    • Xie Li
    • Lu Xi
    • Yin Zi
    • Jakub Drewnowski
    2021 Chinese Journal of Environmental Engineering

    Two different mixed sludge, anaerobic granular sludge(Ｒ1) and anaerobic granular sludge with mature anaerobic ammonium oxidation (ANAMMOX) sludge (Ｒ2 )were used as the inocula in two up-flow reactors to enrich anaerobic ammonia-oxidizing bacteria (AnAOB)，respectively．The total nitrogen removal rate of Ｒ1 reached 74% in 99 days, while Ｒ2 remained above 70% in only 48 days．The content of extracellular polymeric substance (EPS) in the sludge was found to increase with the increase of the influent nitrogen loading，which might attribute to the sludge granulation．It was interesting to notice that the dominant AnAOB genera in two systems were different，i．e．Candidatus Kuenenia (7.92%) inＲ1，and Candidatus Brocadia (15.64%) inＲ2．Candidatus Kuenenia also existed in Ｒ2，accounting for 3.02%．Ｒ1 maintained considerable denitrification efficiency in the case of lower anaerobic ammonium oxidizing bacteria abundance and might have more potential for long-term culture．

  • Chromium‑based metal organic framework for pipette tip micro‑solid phase extraction: an effective approach for determination of methyl and propyl parabens in wastewater and shampoo samples
    • Massoud Kaykhaii
    • Sayyed Hossein Hashemi
    • Fariba Andarz
    • Amin Piri
    • Ghasem Sargazi
    2021 Pełny tekst BMC Chemistry

    Abstract Background A chromium-based metal organic framework was synthesized and employed as an efficient sorbent for pipette tip micro-solid phase extraction and preconcentration of parabens from wastewater and shampoo samples up to sub-ppb level before their spectrophotometric analysis. Results Factors affecting preconcentration including volume and type of solvent, amount of sorbent, number of extraction, and volume and pH of samples were optimized employing one-variable-at-a-time and response surface methodology. Obtained analytical characteristics of the method proves its usefulness for analysis of real samples. Linear range of the method for parabens was 1.0–200.0 μg/L. Detection limit of the protocol was 0.24 µg/L for propyl paraben and 0.25 µg/L for methyl paraben. Reproducibility of the protocol defined as % RSD was better than 5.78%. Synthesized adsorbent can be re-used for at least 20 extractions. Conclusion The method showed a good detection limit and precision for determination of methyl- and propyl-paraben in wastewater and shampoo samples.

  • Cień malarza
    • Krzysztof Wróblewski
    2021

    Obraz prezentowany na wystawie "Zbyszkowi" zorganizowanej w rocznicę śmierci artysty Zbigniewa Kosowskiego. Artyści biorący udział w wystawie: ZBIGNIEW KOSOWSKI; Jarosław Bartołowicz; Jan Buczkowski; Jarosław Ćwiek; Łukasz Głowacki; Laura Gutowska; Krzysztof Hejke; Piotr Kmieć; Mariusz Kozik; Waldemar Mazurek; Jolanta Męderowicz; Andrzej Oboz; Małgorzata Oboz; Anna Panek; Marek Rogulski; Rafał Roskowiński; Adam Skóra; Zbigniew Strzyżyński; Urszula Ślusarczyk; Henryk Widelski; Krzysztof Wróbelewski.

  • City scan as a tool to assess resilience challenges and vulnerabilities at the community level
    • Dominika Wróblewska
    • Rick Heikoop
    • Tanja Hess
    • Floris Boogaard
    • Joep Jansen
    2021

    The majority of the world’s population lives in cities and cities are the key to achieving resilience. Local governments own only part of the land and can only partially decide about measures that should be taken ‘on the ground’. Local governments are therefore highly dependent on individuals, communities, and businesses to adapt and transform and take action in their own backyards or neighbourhoods. Since, for many people, climate change is an abstract concept, it is often dependent on a rational understanding of statistical risk as provided by experts. Involving individuals, communities, and businesses in the process is a huge challenge. The City Resiliency Framework was developed by the 100 Resilient Cities initiative. The framework identified seven characteristics that various city systems need. Two characteristics, reflectiveness and inclusiveness, specifically relate to the importance of community involvement. Reflectiveness is the ability to learn from the past and act in times of crisis. Inclusiveness relates to the processes of good governance and effective leadership that ensure investments and actions are appropriate, address the needs of the most vulnerable, and collectively create a resilient city. This article explores the use of urban sketching and storytelling as methods for capturing the voices and experiences of the community. Narratives arguing for action have often disengaged their audiences from the problem, allowing them to believe that climate change is someone else’s problem, that it is not important for them, or that they are not in a position to make a difference. In urban sketching, vulnerabilities and possible solutions are sketched and shared with the communities as a means to start the resilience discussion. The storytelling method captures stories and past experiences from community members during chronic stress and acute shocks and can help policy makers to better understand the resilience challenges faced by specific communities.

  • Classification of Landscape Physiognomies in Rural Poland: The Case of the Municipality of Cekcyn
    • Anna Górka
    • Kazimierz Niecikowski
    2021 Pełny tekst Urban Planning

    This article presents a methodology and the results of the classification of the rural landscapes physiognomies conducted on the study area located in the municipality of Cekcyn, Poland. The study aimed to develop a landscape identification method that would combine natural, cultural, and visual criteria with which to implement the provisions of the European Landscape Convention. The realization of the European Landscape Convention in Poland is incomplete due to the lack of practical application of landscape assessment in land management and spatial planning at the commune level. The research was intended at helping to fill this void. The study develops a method using which it will be possible to protect the diversity and beauty of Europe’s rural landscapes more effectively. The goal has so far been of little scientific interest in Poland. The physiognomy of the studied area was analyzed with the use of commonly available spatial data and by means of field studies. Physical‐geographical units and cultural characteristics have been designated based on spatial databases. Landscape patterns were identified by analyzing visual fields with the use of both GIS applications and field studies. This practice made it possible to determine physiognomic units of the landscape which are internally coherent and relatively homogeneous in terms of physical‐geographical, cultural, and visual features. Identifying the landscape physiognomy within the designated landscape physiognomic units serves to harmonize spatial alterations in the area of rural communes in processes of land management and planning.