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Detection of illicit chemicals by portable Raman spectrometer
PublikacjaThe Raman spectrometers can be built as the portable devices and can be used in various places to detect illicit chemicals. This method has become popular due to deficiency of other fast methods that could be applied against terrorist attacks or could help police at their work. The conception of a portable Raman spectrometer has been presented. The description enclosures presentation of the prepared device and its possible applications...
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Accurate modeling of layout parasitic to forecast EMI emitted from a DC-DC converter.
PublikacjaThis paper illustrates how to account for all parasitic due to the layout of a power converter (inductive and capacitive), in order to forecast electromagnetic interferences (EMI). The method is generic, and is validated here in the simple example of a DC-DC converter, realized on different technologies: insulated metal substrate (IMS), printed circuit board (PCB). In addition, several layouts aspects will be investigated. Conclusions...
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Research of Accuracy of RSSI Fingerprint-Based Indoor Positioning BLE System
PublikacjaRadio localization in indoor environment is still a challenging task due to environment volatility. In the paper are compared achieved localization accuracies for RSSI-Fingerprinting method utilizing Bluetooth Low Energy (BLE) for two different environments: large empty hall and narrow corridor. Measurements were done by 6 different smartphones of 3 different producers, which makes those measurements unique as accuracies achieved...
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Positive solutions for second order impulsive differential equations involving Stieltjes integral conditions
PublikacjaIn this paper we investigate integral boundary value problems for fourth order differentialequations with deviating arguments.Wediscuss our problem both for advanced or delayedarguments. We establish sufficient conditions under which such problems have positivesolutions. To obtain the existence of multiple (at least three) positive solutions, we use afixed point theorem due to Avery and Peterson. An example is also included to...
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Assessment of Technical Conditions in Adapting a Historic Warehouse's Space Functionality
PublikacjaThe paper is a case study in the assessment of the technical condition of a building that is an immovable monument located in a former shipyard area. Due to the change in the use of the industrial area and the intention to build a production hall, it was necessary to consider the demolition of the historic building, while preserving as many of its historical aspects as possible. The paper presents a detailed description of the...
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Research of Accuracy of RSSI Fingerprint-Based Indoor Positioning BLE System
PublikacjaRadio localization in indoor environment is still a challenging task due to environment volatility. In the paper are compared achieved localization accuracies for RSSI-Fingerprinting method utilizing Bluetooth Low Energy (BLE) for two different environments: large empty hall and narrow corridor. Measurements were done by 6 different smartphones of 3 different producers, which makes those measurements unique as accuracies achieved...
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Prediction of Weld Deformations by Numerical Methods - Review
PublikacjaThe welding process is the basic technique of joining in the shipbuilding industry. This method generates welding distortions that cause a lot of problems during the manufacturing process due to both the time and cost of straightening as well as their influence on later stages of production. Proper preparation of welding processes plays a growing role in the shipbuilding industry and the development of calculating tools is being...
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Distributed measurement system with data transmission secured using XXTEA algorithm
PublikacjaThe paper deals with wireless data transmission security in the distributed measurement and control system. An overview of cryptographic algorithms was presented paying special attention to the algorithm dedicated to units with low processing power, which is important due to minimization of energy consumption. Measurement modules equipped with simple microcontrollers send data wirelessly to the central unit. The transmission was...
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Low-cost Adsorbents Derived from Agricultural By-products/Wastes for Enhancing Contaminant Uptakes from Wastewater: A Review
PublikacjaA major threat to the comfort of human life has been imposed by increased industrialization and urbanization. The generation and disposal of huge amounts of toxic materials and pollutants have heavily contaminated our environment. Some Organics such as synthetic dyes (SD) and heavy metals (HM) are becoming increasingly prevalent as the most dangerous pollutants in soil and surface water environments. They are...
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FFT spectrum based matching algorithm for activedynamic thermography
PublikacjaIn Active Dynamic thermography (ADT) sequences of consecutive temperature distributions are analyzed. In biomedical applications of ADT, the problems of a patient's movements in front of a thermal camera should be eliminated before data analysis. Complete mechanical stabilization of the patients is impossible due to natural voluntary and involuntary moves caused by pulse breathing, etc. This paper presents a simple and efficient...
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Sztuczne sieci neuronowe oraz metoda wektorów wspierających w bankowych systemach informatycznych
PublikacjaW artykule zaprezentowano wybrane metod sztucznej inteligencji do zwiększania efektywności bankowych systemów informatycznych. Wykorzystanie metody wektorów wspierających czy sztucznych sieci neuronowych w połączeniu z nowoczesną technologią mikroprocesorową umożliwia znaczący wzrost konkurencyjności banku poprzez dodanie nowych funkcjonalności. W rezultacie możliwe jest także złagodzenie skutków kryzysu finansowego.
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Biophilic Design: A Trend Watch
PublikacjaDuring the 20th century, many people migrated to cities for employment and economic opportunities, abandoning farming and natural landscapes so their direct connection to the countryside and nature was lost. This process continues to this day with unprecedented urban growth, in fact, it’s estimated 68% of the world population will live in urban areas by 2050. Due to the evolutionary disposition of humans, when people live in an...
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Proposal of a System Loss Model for Body Area Network in Passenger Ferry Environment
PublikacjaIn the paper, proposal of an empirical off-body system loss model for Body Area Networks working in a passenger ferry environment at 2.45 GHz has been presented. The measurements were carried out for dynamic scenarios in the discotheque passenger ferry environment. The general model formula consists of three components: mean system loss, attenuation resulting from the variable antenna position on the human body, and attenuation...
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Multianalyte Calibration Methods for Potentiometric Integrated Sensors System for Determination of Ions Concentration in a Body Fluids
PublikacjaIn recent years, integration and miniaturization of ion-selective electrodes (ISEs) have brought many benefits resulting in the possibility of simultaneous determination of the ions concentration in a small sample volume. One of the key problems related to the preparation of integrated sensors systems (ISSs) is a calibration procedure due to the necessity to calibrate each particular sensor separately. The main aim of the research...
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Dynamics of changes in the concentration levels of organic pollutants in the proglacial waters of the Scott River (Spitsbergen, SW Svalbard)
PublikacjaThe study area covered the NW part of the Wedel Jarlsberg Land. The present study concerns participation of organic pollutants inflow from glacier and seaside plane of Calypsostranda to proglacial waters of the Scott River due to occurrence of precipitation. Concentration ranges for phenols and formaldehyde in water samples are respectively:
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Influence of Property Division on the Technical Condition of a Building
PublikacjaIn this article, the correlation between a technical condition of a building and property division is analyzed and assessed. In the course of the usage of a building, the process of its degradation and the increase in the demands of property occupants can be observed. There is a direct connection between the difficult technical condition of a building and the fragmentation of the ownership structure. Although not considered in...
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Analysis and characterization of coordination compounds by resonance Raman spectroscopy
PublikacjaResonance Raman spectroscopy has become a powerful tool to study excited-state geometries, excited-state charge distributions and photoinduced reaction dynamics in coordination compounds. Due to their rich photophysical properties coordination compounds are utilized for a variety of applications ranging from DNA sensing to photocatalysis. This review features recent applications of various resonance Raman scattering techniques...
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Automatic Threat Detection for Historic Buildings in Dark Places Based on the Modified OptD Method
PublikacjaHistoric buildings, due to their architectural, cultural, and historical value, are the subject of preservation and conservatory works. Such operations are preceded by an inventory of the object. One of the tools that can be applied for such purposes is Light Detection and Ranging (LiDAR). This technology provides information about the position, reflection, and intensity values of individual points; thus, it allows for the creation...
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ECHOES REDUCTION DURING DIGITAL DATA TRANSMISSION IN HYDROACOUSTIC CHANNEL – LABORATORY EXPERIMENT
PublikacjaThe possibility of using a hydroacoustic channel for digital data transmission is very limited. This is due to the effect of multipath propagation of the emitted acoustic wave and the damping of the mechanical wave in this medium, which increase with frequency. The first of these phenomena results in inter-symbol interference disturbances in data transmission systems, including even hundreds of symbols. Due to the number of reflections...
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Thermal and technological aspects of double face grinding of Al2O3 ceramic materials
PublikacjaDouble face grinding with planetary kinematics is a process to manufacture workpieces with plan parallel functional surfaces, such as bearing rings or sealing shims. In order to increase the economic efficiency of this process, it has to be advanced permanently. The temperature in the contact zone of most grinding processes has a huge influence on the process efficiency and the workpiece qualities. In contrast to most grinding...
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Application of GC-MS/MS technique for the determination of benzodiazepines in blood samples
PublikacjaAbstract Benzodiazepines (BZD) are widely used as pharmaceuticals in medicine. However, due to psychostimulatory effect of BZD, in the last decade, they are more and more often used as drugs of abuse. These compounds produce similar effects to classical illicit drugs and are sold as “legal” alternatives to them as new psychoactive substances (NPS). Currently new BZD, named designer benzodiazepines (DBZD), are synthesized each year...
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Rapid assessment of the authenticity of limequat fruit using the electronic nose and gas chromatography coupled with mass spectrometry
PublikacjaCitrus fruits are very popular food products. There are many species and varieties of them. There are also documented cases of some citrus fruits causing a severe allergic reaction. Some species of the citrus fruits, especially hybrid ones show a reduced allergenic effect due to the lack of seeds. There is a need for rapid methods for evaluation of citrus’ botanical origin. During research, the headspace of three citrus fruits...
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Determination of Metals Content in Wine Samples by Inductively Coupled Plasma-Mass Spectrometry
PublikacjaKnowledge about the metal content of wine is very important, for many reasons. Depending on the element, its quantity varies in wine from ng/L to mg/L. Despite the fact that metals are not directly connected to the taste and aroma of the wine, their content should be determined and controlled, because excess is undesirable, and in some cases prohibited, due to potential toxicity. Several analytical procedures for metal determination...
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Magnetic field effects in dye-sensitized and organic solar cells
PublikacjaThe charge recombination and exciton dissociation are generally recognized as the basic electronic processes limiting the efficiency of photovoltaic devices. The aim of this thesis is to understand the electronic processes limiting the operation of efficient solar cells with particular emphasis on the role of electronic states endowed with magnetic dipole moment. The research work is divided into two parts. The first part deals...
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Determinants of COVID-19 Impact on the Private Sector: A Multi-Country Analysis Based on Survey Data
PublikacjaOur paper aims to investigate the impact of COVID‐19 on private sector companies in terms of sales, production, finance and employment. We check whether the country and industry in which companies operate, government financial support and loan access matter to the behaviour and performances of companies during the pandemic. We use a microdata set from a worldwide survey of more than 15,729 companies conducted between April and...
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Innovative Turbine Intake Air Cooling Systems and Their Rational Designing
PublikacjaThe improved methodology of the engine intake air cooling system designing based on the annual effect due to cooling was developed. It involves determining the optimal value of cooling capacity, providing the minimum system sizes at maximum rate of annual effect increment, and its rational value, providing a close to maximum annual effect without system oversizing at the second maximum rate of annual effect increment within the...
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Polyurethanes modified with natural polymers for medical application. I. Polyurethanes/ Chitosan and polyurethane/collagen.
PublikacjaFor over three decades polyurethanes (PUR or PU) have been reported for application in a variety of medical devices. These polymers consist of hard and soft segments, which allow for more subtle control of their structure and properties. By varying the composition of the different segments, properties of PURcan be tuned up for use in many areas of medicine. Recently there is a great interest in modification of biomedical PUR with...
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Clays as Inhibitors of Polyurethane Foams’ Flammability
PublikacjaPolyurethanes are a very important group of polymers with an extensive range of applications in different branches of industry. In the form of foams, they are mainly used in bedding, furniture, building, construction, and automotive sectors. Due to human safety reasons, these applications require an appropriate level of flame retardance, often required by various law regulations. Nevertheless, without the proper modifications,...
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The Many Faces of Enterococcus spp.—Commensal, Probiotic and Opportunistic Pathogen
PublikacjaEnterococcus spp. are Gram-positive, facultative, anaerobic cocci, which are found in the intestinal flora and, less frequently, in the vagina or mouth. Enterococcus faecalis and Enterococcus faecium are the most common species found in humans. As commensals, enterococci colonize the digestive system and participate in the modulation of the immune system in humans and animals. For many years reference enterococcal strains have...
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Heat exchange enhancement of jet impingement cooling with the novel humped-cone heat sink
PublikacjaJet impingement cooling technology is applicable to control temperature of devices, where very high heat flux is generated within a small area. This paper is about the improvement of the jet impingement cooling efficiency by the heat sink geometry modification. Two reference cases were sourced from the literature – flat heat sink and modified one with cone in the jet stagnation region. Such a change improves cooling capability...
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Deep eutectic solvents – Ideal solution for clean air or hidden danger?
PublikacjaThe industrial sector is one of the fastest-growing sources of greenhouse gases, due to its excessive energy consumption to meet the rapidly growing demand for energy-intensive products. The use of deep eutectic solvents (DESs) has been studied extensively in order to cope with these harmful gases, but their usage can be an issue in respect to ecological reasons. Do deep eutectic solvents harm the atmosphere? Yes, these solvents...
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Biological processes modelling for MBR systems: A review of the state-of-the-art focusing on SMP and EPS
PublikacjaA mathematical correlation between biomass kinetic and membrane fouling can improve the understanding and spread of Membrane Bioreactor (MBR) technology, especially in solving the membrane fouling issues. On this behalf, this paper, produced by the International Water Association (IWA) Task Group on Membrane modelling and control, reviews the current state-of-the-art regarding the modelling of kinetic processes of biomass, focusing on...
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MXene-based composites for capacitive deionization – The advantages, progress, and their role in desalination - A review
PublikacjaMXenes, a novel large family of 2D transition metal carbides, carbonitrides and nitrides are currently a “hot topic” in science due to their several fascinating physical and chemical properties. It follows from a rich diversity of their elemental compositions and chemical functionalities. MXenes can form composites with many substances, including polymers or metal oxides, which allows to effective “tune” MXene characteristics to...
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Recent Advancements in Cyclodextrin-Based Adsorbents for the Removal of Hazardous Pollutants from Waters
PublikacjaWater is an essential substance for the survival on Earth of all living organisms. However, population growth has disturbed the natural phenomenon of living, due to industrial growth to meet ever expanding demands, and, hence, an exponential increase in environmental pollution has been reported in the last few decades. Moreover, water pollution has drawn major attention for its adverse effects on human health and the ecosystem....
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Design specification management with automated decision-making for reliable optimization of miniaturized microwave components
PublikacjaThe employment of numerical optimization techniques for parameter tuning of microwave components has nowadays become a commonplace. In pursuit of reliability, it is most often carried out at the level of full-wave electromagnetic (EM) simulation models, incurring considerable computational expenses. In the case of miniaturized microstrip circuits, densely arranged layouts with strong cross-coupling effects make EM-driven tuning...
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Partial inhibition of borohydride hydrolysis using porous activated carbon as an effective method to improve the electrocatalytic activity of the DBFC anode
PublikacjaCarbon materials are commonly used catalyst supports in various types of fuel cells. Due to the possibility of designing their properties, they seem to be attractive and functional additives. In Direct Borohydride Fuel Cells (DBFCs), the electrooxidation reaction of borohydride competes with the undesirable hydrolysis reaction, therefore our work aimed to modify anodes based on a multi-component hydrogen storage alloy with a small...
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Microextraction Techniques Used in the Procedures for Determining Organomercury and Organotin Compounds in Environmental Samples
PublikacjaDue to human activities, the concentrations of organometallic compounds in all parts of the environment have increased in recent decades. The toxicity and some biochemical properties of mercury and tin present in the environment depend on the concentration and chemical form of these two elements. The ever-increasing demand for determining compounds at very low concentration levels in samples with complex matrices requires...
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Ordered titanium templates functionalized by gold films for biosensing applications – Towards non-enzymatic glucose detection
PublikacjaRecently, metal nanostructures evoke much interest due to application potential in highly sensitive detectors in biochemistry and medical diagnostics. In this work we report on preparation and characteristics of thin (1–100 nm) Au films deposited onto highly ordered structured titanium templates for SERS (Surface Enhanced Raman Spectroscopy) and electrochemical sensing. The Ti templates are formed by selective removal of TiO2 nanotubes...
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Determination of Selected Metals in Fruit Wines by Spectroscopic Techniques
PublikacjaThe determination of metals in different types of food and beverages samples has drawn significant attention due to several reasons with the most important one being the nutritional and toxic effects of these elements or their compounds. The knowledge of certain elements content in wines/fruit wines is of special interest due to their toxicity in case of excessive intake and also the effect they seem to have on the organoleptic...
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Polymer journal bearings behaviour research under limited lubrication and cooling conditions conducted on high torque test rig
PublikacjaPolymer journal bearings are frequently used as a water-lubricated bearings of small marine units’ propeller shafts . Choice of these bearings is based on their simple construction and relatively low purchase and maintenance costs. Although properly designed and installed water lubricated bearings may well last for over a decade, rapid wear or failure of these bearings can be observed...
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NEW CONCEPT OF HYBRID PROPULSION WITH HYDROSTATIC GEAR FOR INLAND WATER TRANSPORT
PublikacjaThe article presents the development of author’s concept of a diesel/hydraulic propulsion system for inland watercraft. Due to specific nature of vessel navigation on rivers, classical propulsion systems with shaft lines can be effectively replaced by systems with hydraulic power transmission. A solution is also presented of a hybrid design with extra electric port having the form of a pumping system driven from a battery of accumulators....
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Stability of truss with side - supports. The case of linear and rotational elastic supports
PublikacjaThe research is devoted to study lateral buckling of truss with linear and rotational elastic side-supports. Geometrically nonlinear analysis of example truss with linear and rotational elastic sidesupports is carried out. The limit normal force in compressed chord of the truss due to stiffness of side supports is calculated. The elastic support reaction in relation to force in compressed chordand coefficient of buckling length...
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Perforating systems in shale gas recovery
PublikacjaHydraulic fracturing is common method of shale gas recovery. Due to environmental, economical and technological problems many alternative technologies have been developed. One of the most promising group of technologies is based on perforating systems. This paper describes theoretical and practical aspects of best known technologies used to create perforations. New perforating/fracturing technologies which can replace hydraulic fracturing...
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Compensation of Dead Time Effects for Shunt Active Power Filters
PublikacjaThe paper presents a comprehensive approach to the compensation of the grid current distortion for shunt active power filter systems. Four different sources of current distortion are addressed: imperfect grid synchronization caused by the distortion in the grid voltages, time delays in the estimation of compensating currents and grid voltages, fluctuations of the dc bus voltage, and the distortion of inverter output voltages due...
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Peculiarities associated with testing polyetheretherketone (PEEK) in a model rolling contact
PublikacjaPolyetheretherketone (PEEK) was investigated using a modified version of the four-ball tester in which the upper forth ball was replaced by a cone in such a way that kinematics of the four-ball configuration were fully preserved. Rotation of the cone enforced orbiting and rolling of the ceramic balls around the polymer cup. The results produced some unexpected peculiarities in the wear of ceramic balls which, in principle, should...
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Key activities to improve energy management in DC microgrids connected by urban traction
PublikacjaDC MicroGrids must have Energy Management Systems to guarantee efficient, dependable, and environmentally friendly electricity. The application of Model Predictive Control, proved to be helpful due to its adaptability and capacity to use non-linear models. This paper, based on an extensive literature review, identifies and discusses the three key activities to improve the characteristics of DC MicroGrids, i.e.: the use of Energy...
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DIFFRACTION PHASE MICROSCOPY FOR OBSERVATION ON RED BLOOD CELLS FLUCTUATION
PublikacjaNowadays there is quite huge need for more and more precise and effective fast diagnostics methods in hematology diseases. One of the most important blood components are erythrocytes – RBCs (Red Blood Cells). Due to their size they are easy to observe using microscopy. It is commonly known that the shape and lifetime of RBCs allows for early disease identification. Authors present special measurement system for RBCs fluctuations observation...
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Analiza numeryczna i analityczna przekrycia w kształcie powłoki synklastycznej o podstawie kwadratowej
PublikacjaW pracy poruszono problem obliczania przekrycia żelbetowego w kształcie powłoki synklastycznej ściętej o podstawie kwadratowej. Przedstawiono obliczenia analityczne i numeryczne sił w powłoce. Powłoka jest poddana działaniu głównie sił ściskających, co jest korzystne dla tego typu konstrukcji. W strefie brzegowej i podporowej konieczne jest wymiarowanie na mimośrodowe ściskanie i rozciąganie z uwagi na znaczący wzrost momentów...
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Induction of chirality in 4,4'-azopyridine by halogen-bonding interaction with optically active ditopic donors
PublikacjaOptically active ditopic halogen bond donors bearing two 4-iodotetrafluorophenyl groups were obtained by reaction of chiral diols with iodopentafluorobenzene. Co-crystallization of these donors with anti-4,4′-azopyridine afforded binary complexes containing infinite chains of the alternating component molecules connected by halogen bonds. The solid state CD measurements confirmed that complexation induces optical activity of the...
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Selected problems of sensitivity and reliability of a jack-up platform
PublikacjaThe paper deals with sensitivity and reliability applications to numerical studies of an off-shore platform model. Structural parameters and sea conditions are referred to the Baltic jack-up drilling platform. The study aims at the influence of particular basic variables on static and dynamic response as well as the probability of failure due to water waves and wind loads. The paper presents the sensitivity approach to a generalized...