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Innowacyjny moduł ultradźwiękowy systemu monitoringu technicznego mostu podwieszonego w Rzeszowie
PublicationW artykule przedstawiono system monitoringu technicznego konstrukcji mostu podwieszonego nad rzeką Wisłok. System będzie wyposażony w dodatkowy moduł ultradźwiękowy umożliwiający śledzenie degradacji mechanicznej betonu w pylonie mostu. Wczesne wykrywanie stref mikropęknięć, przed pojawieniem się widocznych rys, umożliwia monitorowanie amplitud propagującej fali ultradźwiękowej oraz analizę sygnałów w dziedzinie częstotliwości.
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Wpływ mikrosfer-frakcji odpadów paleniskowych na mikrostrukturę i wybrane właściwości uzytkowe
PublicationIn this study, the microspheres samples were collected from national power station „Dolna Odra”. In this study, the following materials were used: Portland cement class 32,5R and aggregates of 2-8 and 8-16 fractions and natural sand with a maximum grain size of 2 mm and water. Concrete mixtures were made with microspheres additions of 15%, 25% and 40%. A constant water to binder ratio (w/b) of 0,52 was used throughout the investigation....
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Comparison of Different Measurement Techniques as Methodology for Surveying and Monitoring Stainless Steel Chimneys
PublicationThe measurement of a chimney axis is an engineering geodesy task. These measurements allow to assess the technical condition of chimneys and are usually carried out for reinforced concrete chimneys. When measuring high chimneys, the main problem may be the need to go a long distance to take a measurement. The surface of the chimney can also be problematic because it can absorb so much light from the range finder that total station...
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Analysis of compressive forces in CFGFT cylindrical pillars and their coatings using laboratory tests and metric spaces
PublicationThe article discusses compressive forces tests in composite-concrete pillars with the use of laboratory active experiment including the factors and properties of materials which have a significant impact on the test results and their repeatability. A polymer composite based on glass fiber reinforced resin with different fiber beam angles (20, 55 and 85) was used as a buffer/coat of the pole. Due to the problems with direct comparison...
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Diagnostics of thermal processes in antenna systems of broadcast stations
PublicationDiagnostics is an important element associated with the operation of a radio antenna systems, allowing earlier detection of potential damage. Thermography is one of the diagnostic tools, which allows for non-invasive assessment of technical condition. It brings together both financial savings associated with the removal of the damage and the potential effects caused by it. The article presents an example of using a thermal imaging...
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The Influence of Shear Deformation in analysis of plane frames
PublicationThe focus of the paper is to investigate the influence of shear deformation effect on the distribution of internal forces and frame deformation. To estimate shear deformation effect, the Timoshenko beam theory and the concept of shear deformation coefficients are used. Analysis of example frames gives the possibility to evaluate what have the most impact on size of shear deformation and in which type of frames the shear deformation...
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Badania eksperymentalne słupów CFST z betonem zwykłym i ekspansywnym
PublicationPraca przedstawia badania eksperymentalne ponad 40 słupów CFST. Analizie poddano wyniki siły niszczącej słupy w aspekcie grubości stalowego płaszcza, smukłości słupa, rodzaju betonu wypełniającego stalową rurę (zwykły i ekspansywny) i jego wytrzymałości a także sposobu obciążania słupa (przez rdzeń lub przez cały przekrój). Sprawdzono efektywność słupów CFST z użyciem betonu ekspansywnego i zwykłego rozumianą jako stosunek nośności...
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Wpływ ukształtowania zbrojenia na zarysowanie i nośność żelbetowego węzła tarczowego ze wspornikiem
PublicationPraca ma charakter eksperymentalno-teoretyczny i dotyczy zagadnień związanych z żelbetowymi tarczami pracującymi w przestrzennym układzie konstrukcji budynków. Celem niniejszej dysertacji było określenie wpływu głównych parametrów jakimi są sposób ukształtowania zbrojenia i smukłość ścinania na zarysowanie i nośność żelbetowego przestrzennego węzła tarczowego ze wspornikiem. Na podstawie aktualnego stanu wiedzy, opracowano program...
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Multifrequency Wideband Sonar Array
PublicationThis paper describes of new approach to Multifrequency Wideband Arrays (MWA),applied piezocomposite technologies of the array elements. MWA operating in transmitting(Tx) and receiving (Rx) mode on two or three bands, requires state-of-the-art technology andefficient array designing than conventional array in which separate arrays for every band oreven separate Tx and Rx transducers/arrays are used. The new piezocomposite elements...
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Identification of the Agile Mindset and Its Comparison to the Competencies of Selected Agile Roles
PublicationIn this paper we present the results of the identification and evalua-tion of the elements of an agile mindset as well as its comparison to the compe-tence models for the roles of Scrum Master, Product Owner and agile analyst. We have identified 70 unique agile mindset elements from literature and 5 in-terviews with experts. Based on an opinion survey among 52 agile practitioners we evaluated the importance of 26 selected elements...
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The central server of the Border Guard's distributed multimedia system for monitoring and visualisation of ongoing and archival events
PublicationThe paper presents the architecture and functionalities of the central server (CENTER) of the distributed system for the Polish Border Guard (BG) for monitoring maritime areas. The overall system has been extended to incorporate, apart from map data, also different multimedia elements such as video from cameras or audio from telephone connections operated by BG units. This requires new system elements: Archive Servers for storing...
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Empirically adjusted and consistent set of EHT valence orbital parametersfor all elements of the periodic table. Modelling Simul. Mater. Sci. Eng. [online]. 2004 vol. 12 [dostęp..] s. 21-32, 3 rys. 3 tab. bibliogr. 35 poz. Dostępny w Internecie stacks.iop.org/MSMSE/12/21.ISSN 0965-0393 Jednorodny skorygowany empirycznie zbiór parametrów EHT dla orbitali walen- cyjnych pierwiastków.
PublicationModel atomu HFS został zmodyfikowany poprzez przypisanie każdemu z atomówindywidualnego parametru ŕ. Wartości ŕ dobrano w oparciu o pierwszy poten-cjał jonizacji atomu. Parametry EHT wyznaczono w oparciu o tak zmodyfikowa-ny model HFS.
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The influence of the grid density of measurement points on damage detection in an isotropic plate by the use of elastic waves and laser scanning Doppler vibrometry
PublicationDamage detection in structural components, especially in mechanical engineering, is an 2 important element of engineering practice. There are many methods of damage detection, in which 3 changes in various parameters caused by the presence of damage are analysed. Recently, methods 4 based on the analysis of changes in dynamic parameters of structures, i.e. frequencies or mode shapes 5 of natural vibrations, as well as changes in...
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Receptor for advanced glycation end‐products: Biological significance and imaging applications
PublicationThe receptor for advanced glycation end-products (RAGE or AGER) is a transmembrane, immunoglobulin-like receptor that, due to its multiple isoform structures, binds to a diverse range of endo- and exogenous ligands. RAGE activation caused by the ligand binding initiates a cascade of complex pathways associated with producing free radicals, such as reactive nitric oxide and oxygen species, cell proliferation, and immunoinflammatory...
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Monitoring Regenerative Heat Exchanger in Steam Power Plant by Making Use of the Recurrent Neural Network
PublicationArtificial Intelligence algorithms are being increasingly used in industrial applications. Their important function is to support operation of diagnostic systems. This paper pesents a new approach to the monitoring of a regenerative heat exchanger in a steam power plant, which is based on a specific use of the Recurrent Neural Network (RNN). The proposed approach was tested using real data. This approach can be easily adapted to...
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Monitoring of a historic sacral building on an example Basilica St. Nicholas in Gdańsk
Publicationhe paper describes the case of monitoring the technical condition of a historic sacral building after a failure and during renovation works. In order to monitor the condition of the building, safely conduct diagnostic work, identify the causes of failures andsafely carry out renovation works, a detailed Facility Monitoring Program has been developed, which has been implemented, is operational and is a source of valuable data used...
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Analiza nośności zabytkowych fundamentów w kontekście jakości użytych zapraw Analysis of the Load-Bearing Capacity of Historical Foundations in the Context of the Quality of Mortar Used
PublicationStructures of historical buildings usually have the form of masonry elements. The weakest component of such elements is mortar, especially in stone foundations, which were often used in the with a focus on the modeling of mortar as a joint connecting stones in a characteristic medieval foundation. Different types of mortar: cement, cement-lime, lime and gypsum mortars, were examined. A numerical analysis was carried out on the...
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CAUSALITY IN MODELS OF THERMAL PROCESSES IN SHIP ENGINE ROOMS WITH THE USE OF BOND GRAPH (BG) METHOD
PublicationWith a single approach to modeling elements of different physical nature, the method of Bond Graph (BG) is particularly well suited for modeling energy systems consisting of mechanical, thermal, electrical and hydraulic elements that operate in the power system engine room. The paper refers to the earlier presented new concept of thermal process modeling using the BG method. The authors own suggestions for determining causality...
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Implementing decisional trust: a first approach for smart reliable systems
PublicationIn this article, we introduce the necessary elements that must be integrated in order to achieve a decisional technology that is trustworthy. Thus, we refer to such technology as decisional trust. For us, decisional trust can be achieved through the use of elements such as the decisional DNA, reflexive ontologies, and security models; and therefore, we present in this article a framework that was used for the implementation of...
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The structure of the data flow in integrated urban traffic management systems – the case of TRISTAR system
PublicationThe purpose of the article is to offer some insight into the data flow architecture in the Tri-City’s integrated traffic management system called TRISTAR. To that end selected elements of TRISTAR are identified and described as well as the structure for collecting and exchanging data within different sub-systems. Finally, the article highlights how the TRISTAR system can be extended by adding new elements and modules.
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Rheological, Mechanical, Microstructural and Radiation Shielding Properties of Cement Pastes Containing Magnetite (Fe3O4) Nanoparticles
PublicationThis work examines the influence of iron oxide nanoparticles (Fe3O4 NPs) on neutron and gamma-ray radiation shielding characteristics of Portland cement paste. Experimental evaluations were supplemented with theoretical studies using NXCom program. Portland cement pastes with 5, 10, 15, 20, and 30 wt% of nanomagnetite cement replacement were produced. Moreover, rheological, early strength development, compressive strength, and...
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The effect of an active force while slide diamond burnishing of wooden shafts upon process quality
PublicationThe quality of the surface of wooden elements that have been turned and burnished has got a crucial meaning in the whole production process flow, since the obtained effects affect the quality of the wooden surface after finishing (coating, painting). In the paper, selected results of the investigation of the effect of the burnishing process on the surface quality of the elements after turning are presented. Research experiments...
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The aluminium and polycarbonate covering to the roof over the stadium in Gdańsk
PublicationThis paper presents information about structural elements of the roof covering to the stadium in Gdansk built for the 2012 European Football Championship in Poland and the Ukraine. The paper discusses elements of the polycarbonate covering, the supporting structure and the drainage system. It also provides information about tests and research performed prior to construction, which determined the solutions adopted as well as...
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Problems of modelling toxic compounds emitted by a marine internal combustion engine for the evaluation of its structure parameters
PublicationThe paper presents the possibility of using an analytical study of the engine exhaust ignition to evaluate the technical condition of the selected components. Software tools available for the analysis of experimental data commonly use multiple regression model that allows the study of the effects and iterations between model input quantities and one output variable. The use of multi-equation models gives a lot of freedom in the...
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Linear Micropolar Elasticity Analysis of Stresses in Bones Under Static Loads
PublicationWe discuss the finite element modeling of porous materials such as bones using the linear micropolar elasticity. In order to solve static boundary-value problems, we developed new finite elements, which capture the micropolar behavior of the material. Developed elements were implemented in the commercial software ABAQUS. The modeling of a femur bone with and without implant under various stages of healing is discussed in details
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AN ATTEMPT AT IDENTIFYING THE INFLUENCE OF TEST HEAD ASSEMBLY STIFFNESS ON THE RESULTS OF A TRIBOLOGICAL EXPERIMENT CONDUCTED UNDER MICRO-OSCILLATION CONDITIONS
PublicationThe outcome of experimental research on a group of dry bearing materials carried out under small oscillation conditi ons and using a test rig designed and made at Gdansk University of Technology inspired the decision to find out if the stiffness of test head elements in fluenced the generated results. Therefore, a computer model utilising finite elements was devised and used to simulate the workings of the test head. The mode l...
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Determining the leakage current resistive component by the orthogonal vector method
PublicationThe measurement of the metal – oxide surge arresters (MOSA) leakage current and the analysis of its components is a key diagnostic criterion according to technical standards. During on site MOSA condition assessment, the easy way is based on the measurement only leakage current, without the inconvenient live working measurements of supply voltage. Orthogonal vectors method of determination the resistive leakage current is presented....
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Uncertainty analysis of measuring system for instantaneous power research
PublicationThe paper presents a metrological analysis of the measurement system used for diagnosis of induction motor bearings, based on the analysis of the instantaneous power. This system was implemented as a set of devices with dedicated software installed on a PC. A number of measurements for uncertainty estimation was carried out. The results of the measurements are presented in the paper. The results of the aforementioned analysis helped...
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Dome over the Gdynia seaport building
PublicationThe paper presents the description of structure and the selected problems of the technical condition, as well as the strength analysis of the thin-walled reinforced concrete shell which has been making a covering of the main hall of the Gdynia Seaport Building through the last 80 years. The rectangle projection of four single curvature shells of the dome was shaped out of mutual perpendicular intersection of two cylindrical shells. The...
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Przyczyny uszkodzeń i sposób naprawy posadzki ze styrobetonu
PublicationW artykule opisano uszkodzenia, badania i sposób naprawy posadzki wykonanej na istniejącym stropie żelbetowym o powierzchni ok. 1050 m2 i podłożu ze styrobetonu. W posadzce stwierdzono znaczne uszkodzenia w postaci zarysowań, odspojeń i nierówności. W celu określenia ich przyczyn wykonano badania in situ oraz badania laboratoryjne. Stwierdzono, że przyczyną powstania uszkodzeń są błędy wykonawcze. Wykonano próbną naprawę uszkodzeń...
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Decision-Making Models of the Human-Operator as an Element of the Socio-Technical Systems
PublicationThe authors of the chapter proved that the fundamental intellectual processes, which lie on the basis of decision-making behavior of the human-operator, could be identified on the bases on the analogies with the devices (elements). The basic intellectual processes of the Rational decision-making models can be adequately identified by the transient processes of the PID-controller; the intellectual processes of the Bounded Rationality...
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Non-destructive Diagnostics of the Floor in the Gdańsk Crane Using Ground Penetrating Radar = Diagnostyka nieniszcząca posadzki w gdańskim Żurawiu z zastosowaniem metody georadarowej
PublicationThis paper presents the results of a ground penetrating radar (GPR) survey carried out at the Crane in Gdańsk. The measurements were conducted on the floor of the southern and northern towers. The aim of the experiment is to assess the possibility of detecting anomalies beneath the floor. The surveys were carried out in a non-destructive manner, using a georadar unit with 2 GHz and 400/900 MHz antennas. This paper compares the...
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Do You Know What You Drink? Comparative Research on the Contents of Radioisotopes and Heavy Metals in Different Types of Tea from Various Parts of the World
PublicationThe aim of this study was to assess the potential health risks of radioactive elements and heavy metals ingested through the consumption of various types of tea imported to the Polish market (black, green, red, oolong and white). The concentrations [Bq/kg] of radionuclides (40K, 137Cs, 226Ra, 210Pb and 228Th) in tea leaves before and after brewing were measured using γ-ray spectrometry with high-purity germanium (HPGe). The concentrations...
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Experimental study on plate modal parameters
PublicationTest doświadczalny jest częścią systemu diagnostycznego. Autorzy badają wpływ dodatkowej masy na parametry modalne wolno popartej stalowej płytyi. Artykół przedstawia technikę wyznaczania parametrów modalnych dla systemów monitorowania konstrukcji.The experimental test introduced in the paper is the part of the diagnostic system. The authors investigate the influence of the additional mass on modal parameters of simply supported...
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Influence of separation gap on the structural response of colliding structures under earthquake excitation
PublicationThe high level of urbanization in the XXIst century forces the designers to design closely-separated structures and to take into account many factors influencing their response during seismic excitation, which are the most unpredictable loads which can affect civil engineering structures. Interactions between insufficiently adjacent buildings, known as the earthquake-induced structural pounding, may cause serious damage to the structures,...
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Comparison of Absorbed and Intercepted Fractions of PAR for Individual Trees Based on Radiative Transfer Model Simulations
PublicationThe fraction of absorbed photosynthetically active radiation (fAPAR) is a key parameter for estimating the gross primary production (GPP) of trees. For continuous, dense forest canopies, fAPAR, is often equated with the intercepted fraction, fIPAR. This assumption is not valid for individual trees in urban environments or parkland settings where the canopy is sparse and there are well-defined tree crown boundaries. Here, the distinction...
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Seismic damage diagnosis in adjacent steel and RC MRFs considering pounding effects through improved wavelet-based damage-sensitive feature
PublicationThis paper aims to propose complex Morlet (cmorfb-fc) wavelet-based refined damage-sensitive feature (rDSF) as a new and more precise damage indicator to diagnose seismic damages in adjacent steel and Reinforced Concrete (RC) Moment Resisting Frames (MRFs) assuming pounding conditions using acceleration responses. The considered structures include 6- and 9-story steel and 4- and 8-story RC benchmark...
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Estakada E2 - kluczowy obiekt Obwodnicy Wałcza
PublicationW artykule przedstawiono uwarunkowania i przebieg projektowania estakady E2 z betonu sprężonego w ciągu Obwodnicy Wałcza. Pokazano efekt procesu optymalizacji projektu pierwotnego. Opisano przeprowadzone analizy wynikające z przyjętej technologii nasuwania podłużnego oraz istotne aspekty, które należy poruszyć przy wyborze tej technologii. Zaprezentowano modele numeryczne konstrukcji przęseł i metodę analizy z uwzględnieniem pracy...
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Wybrane metody diagnostyki łożysk silników indukcyjnych oparte o pomiar prądu
PublicationW artykule zawarto przegląd wybranych metod diagnostyki łożysk silnika indukcyjnego, bazujących na pomiarach prądu zasilającego. Jedno z nowych rozwiązań przetwarzania sygnałów zostało zaadaptowane przez autorów do stosowanego przez nich systemu diagnostycznego. Wyniki wstępnych badań symulacyjnych zweryfikowanych badaniami na rzeczywistym obiekcie wskazują, że rozwiązanie to ułatwia diagnozowanie. Autorzy zamierzają prowadzić...
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A System for Heart Sounds Classification
PublicationThe future of quick and efficient disease diagnosis lays in the development of reliable non-invasive methods. As for the cardiac diseases – one of the major causes of death around the globe – a concept of an electronic stethoscope equipped with an automatic heart tone identification system appears to be the best solution. Thanks to the advancement in technology, the quality of phonocardiography signals is no longer an issue. However,...
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Technical State Assessment of Charge Exchange System of Self-Ignition Engine, Based On the Exhaust Gas Composition Testing
PublicationThis paper presents possible use of results of exhaust gas composition testing of self - ignition engine for technical state assessment of its charge exchange system under assumption that there is strong correlation between considered structure parameters and output signals in the form of concentration of toxic compounds (ZT) as well as unambiguous character of their changes. Concentration of the analyzed ZT may be hence considered...
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The protocol for using elastic wall model in modeling blood flow within human artery
PublicationMedical diagnostic tools will play a major role in the future for an effective patient treatment and reduction their mortality, related to the cardiovascular system diseases (CVDs). There is an urgent need for developing diagnostic procedure to be robust, reliable, accurate and efficient, in the framework of a paradigm shift. Application of numerical techniques is seen as a perspective tool for such purpose. Nevertheless, existing...
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Stanowisko do diagnostyki i regulacji wyzwalaczy przekaźników w obwodach lokomotyw elektrycznych
PublicationFast circuit breaker and protective relays play an important role of protecting locomotive’s electrical circuits from damage caused by short circuit or overload. Undisturbed operation and proper circuit protection depends on the technical condition and fine calibration of the over-current trips. Therefore the relays should be subject to periodic inspection and adjustment due to locomotive maintenance schedule. A test stand for...
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Poroelastic Low Noise Road Surfaces
PublicationNoise is one of the most important problems related to road traffic. During the last decades, noise emitted by engine and powertrain of vehicles was greatly reduced and tyres became a clearly dominant noise source. The paper describes the concept of low noise poroelastic road surfaces that are composed with mineral and rubber aggregate bound by polyurethane resin. Those surfaces have a porous structure and are much more flexible...
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Ultra Low Noise Poroelastic Road Surfaces
PublicationNoise is one of the most important environmental problems related to road traffic. During the last decades, the noise emitted by the engines and powertrains of vehicles was greatly reduced and tires became a clearly dominant noise source. The article describes the concept of low noise poroelastic road surfaces that are composed of mineral and rubber aggregate bound by polyurethane resin. Those surfaces have a porous structure and...
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The bridge over Regalia River in Szczecin - design and construction.
PublicationNowoclowa Route is the largest projekt in Szczecin, that consists of 11 km of roads 3,3 km bridges and viaducts, including three parallel bridges across Regalica River (the east arm of Odra River), 535 m long, with the spans: 59+90+90+116+116+64m. The bridge structure consist of two steel plate girders composite with reinforced concrete deck slab. The design and the construction of the bridge are described in the paper.
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N-(diphenoxyphosphoryl)succinimide:synthesis and reaction with alkoxides
PublicationReakcja sukcynoimidu z chlorkiem difenylofosforowym w obecności lda a prowadzi do powstania amidofosforanu. ta sama reakcja prowadzona w obecności wodorku sodu pozwala na otrzymanie fosforylowanego sukcynoimidu, który w reakcji z alkoholanami w nasteptwie otwarcia pierścienia, prowadzi do do analogów amidofosforanu z dobrymi wydajnościami.
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Simple method for preparation of Dialkyl (2,3-dihydro-1,3-thiazol-2-yl)-phosphonates
PublicationAbstract A simple synthesis of dialkyl (2,3-dihydro-1,3-thiazol-2-yl)-phosphonates from thiazoliumsalts and trialkyl phosphites is described. The series of dialkyl (2,3-dihydro-1,3-thiazol-2-yl)-phosphonates with various substituents in positions 3, 4, and 5 of the thiazole ring wereprepared. However, only phosphonates with an aryl on the nitrogen atom were stable enoughfor chromatographic purification, although all the new phosphonates...
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Synthesis and Properties of Di-isopropylamino Derivatives of Diphosphanes and Triphosphanes: The X-Ray Structure of (iPr2N)2P-P(SiMe3)2
PublicationPrzeprowadzono reakcję (iPr2N)2PCl z P(SiMe3)2Li w wyniku której otrzymano difosfan (iPr2N)2P-P(SiMe3)2. Strukturę związku określono przy pomocy rentgenowskiej analizy strukturalnej. Otrzymano także pochodną litową (iPr2N)2P-P(SiMe3)Li w rekcji z nBuLi. W reakcji (iPr2N)2PCl z (iPr2N)2P-P(SiMe3)Li otrzymano trifosfan (iPr2N)2P-P(SiMe3)-P(NiPr2)2 z dużą wydajnością. Próby otrzymania pochodnej litowej (iPr2N)2P-PLi-P(NiPr2)2 zakończyły...
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Potassium Tri-tert-butoxysilanethiolates: Synthesis, Properties, and Crystal and Molecular Structures of [(tBuO)3SiSK]6[THF]2·2THF, {[(tBuO)3SiS]2K2}n, and [(tBuO)3SiSK]4[H2O]4·C6H6
PublicationW reakcji tri-tert-butoksysilanotiolu z potasem otrzymano trzy nowe związki:[(tBuO)3SiSK]6[THF]2·2THF, {[(tBuO)3SiS]2K2}n, i[(tBuO)3SiSK]4[H2O]4·C6H6. Stanowią one dogodne substraty w syntezach kompleksów silanotiolanowych metali przejściowych. Charakteryzują się one również różnorodnością tworzonych układów. Rentgenowska analiza strukturalna wykazała, iż tworzą one trzy typy makrocząsteczkowych układów, w których...