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Search results for: PCBS
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Thermal properties of a cement composite containing phase change materials (PCMs) with post-pyrolytic char obtained from spent tyres as a carrier
PublicationThis work examines the possible use of post-pyrolysis char made from spent vehicle tyres as a carrier for phase change materials (PCM), which could be used as an additive to cement mortar. Because of the ability of PCM to accumulate heat, the cement composite obtained from it, apart from its structural and strength properties, will acquire an additional energy storage function, which can be very important for energy-saving construction. In...
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Genetic diversity of Legionella pcs and pmtA genes and the effect of utilization of choline by Legionella spp. on induction of proinflammatory cytokines
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Comparison of different extraction techniques of polychlorinated biphenyls from sediments samples.
PublicationIn this work, problems that may occur during determination of trace levels of polychlorinated biphenyls in sediment samples are described. Main error sources are connected with extraction of analytes prior to final determination. During model studies, polychlorinated biphenyls have been extracted from sedimentreference material (METRANAL 2) with the use of different solvents (dichloromethane, hexsane, and toluene); the process...
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Validation of high-resolution 3D patient QA for proton PBS and IMPT using laser CT of improved polymer gel dosimeters
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Ti/TiO2 nanotubes sensitized PbS quantum dots as photoelectrodes applied for decomposition of anticancer drugs under simulated solar energy
PublicationOne of the challenges in research into photoelectrocatalytic (PEC) degradation of pollutants is finding the appropriate photoanode material, which has a significant impact on the process efficiency. Among all others, photoelectrodes based on an ordered TiO2 nanotube arrays are a promising material due to well-developed surface area and efficient charge separation. To increase the PEC activity of this material, the SILAR method was...
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Oznaczanie analitów z grupy WWA i PCB w próbkach wody. Źródła błędów, identyfikacja i oszacowanie ich wielkości.
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Removal of persistant organic pollutants from landfill leachates treated in three constructed wetland systems
PublicationThe objective of the study was assessment of occurrence and removal of two groups of persistent organic pollutants: polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) in landfill leachate (LL) treated in three constructed wetland systems (CWs) of different construction and flow regime. Two subsurface flow systems (SSF) were analyzed: one with horizontal flow and the second one consisting of two vertical...
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Comparison of different techniques for extracting Polychlorinated Biphenyls from bottom sediment samples using Isotope Dilution Mass Spectrometry
PublicationIn this work, problems that may occur during determination of trace levels of polychlorinated biphenyls in sediment samples are described. The main error sources are connected with extraction of analytes prior to final determination. During model studies, polychlorinated biphenyls have been extracted from sediment reference material (METRANAL 2) with the use of different solvents (dichloromethane, hexane, and toluene); the process...
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Chemical composition of water from roof in Gdańsk, Poland
PublicationThis study deals with the assessment of roof runoff waters from the region of Gdansk collected during the winter season (2007/2008). The chemical analysis includes 16 chemical variables: major ions, PAHs and PCBs measured at 3 sampling sites for 6-14 rain events. Although the data set is of limited volume the statistical data treatment using self-organizing maps (SOM) reveals the main factors controlling roof runoff water quality...
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Expanded graphite assistant construction of gradient-structured char layer in PBS/Mg(OH)2 composites for improving flame retardancy, thermal stability and mechanical properties
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Interspecific and intraspecific variation in organochlorine pesticides and polychlorinated biphenyls using non-destructive samples from Pygoscelis penguins
PublicationAs humans are present in Antarctica only for scientific and tourism-related purposes, it is often described as a pristine region. However, studies have identified measurable levels of Persistent Organic Pollutants (POPs), such as organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs), in the Antarctic region. These are highly toxic anthropogenic compounds with tendency to travel long distances and reach remote environments, where...
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Porównanie technik oczyszczania ekstraktów z żywności zawierającej pestycydy chloroorganiczne oraz anality z grupy PCB = The comparison of techniques for the clean-up of food extracts containing organochlorine pesticides and polychlorinated biphenyls
PublicationW pracy przedstawiono wyniki badań dotyczących opracowania metody oczyszczania ekstraktów z żywności o zawartości tłuszczu od 10 do 13% opartej na technice ekstrakcji do fazy stałej przy jakościowym i ilościowym oznaczaniu związków chloroorganicznych. W tym celu porównano odzyski wybranych analitów chloroorganicznych w przypadku zastosowania różnych rozpuszczalników na etapie izolacji analitów z matrycy oraz w przypadku oczyszczania...
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A review of phase change materials and heat enhancement methodologies
PublicationPhase change materials (PCMs) are an efficient alternative to store and release heat at a specific range of temperature. Here PCMs and heat enhancement methodologies for PCM storage are reviewed. A short overview of PCMs and their applications is presented in addition to the progress during the last 10 years. Heat enhancement techniques, that is, extended surfaces, multiple and composite PCMs, and encapsulation techniques, are...
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Determination of POPs in environmental matrices - proficiency tests for Polish laboratories
PublicationKatedra Chemii Analitycznej Wydziału Chemicznego PG we współpracy ze Stowarzyszeniem RefMat oraz firmą LGC Promochem Sp. z o.o. prowadzi od 2003 roku wieloletni projekt badań biegłości laboratoriów. Celem badań jest określenie biegłości laboratoriów w zakresie oznaczania związków organicznych (anality z grupy PCB, WWA, pestycydy) w próbkach środowiskowych. W ramach projektu przeprowadzono dotychczas trzy badania biegłości dotyczące...
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Surface sediments pollution due to shipwreck s/s “Stuttgart”: a multidisciplinary approach
PublicationShipwrecks may pose a serious source of pollution for marine ecosystems. For this reason, it is of great importance to perform a marine ecosystem risk assessment due to plausible wreck presence. One of elements of such an assessment is determining the state of the environment in the vicinity of the wreck. In the work presented, the results of studies on surface sediments samples collected around the s/s Stuttgart ship sunk during...
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Bisphenol A analogues and metabolic syndrome in women with polycystic ovary syndrome
PublicationBisphenols (BPs) have become a chemical group of special interest due to their ability to interfere with the endocrine system and their ubiquitous presence in the environment. As some of them possess mild estrogenic and anti-androgenic effects, they might be associated with the diagnosis of polycystic ovary syndrome (PCOS). Acting on multiple tissues, BPs exposure may lead to metabolic derangements characteristic for metabolic...
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The potential role of bisphenol A in the pathogenesis of polycystic ovary syndrome
PublicationPolycystic ovary syndrome (PCOS) is the most common endocrinopathy in women of reproductive age, that lead to infertility, type 2 diabetes and coronary heart disease. Bisphenol A (BPA) is one of the most abundant chemicals produced worldwide and is used as a plasticizer in daily life. Nowadays it is also well know that it can interact with estrogen receptors, androgen receptors and peroxisome proliferatoractivated receptors g (PPARg)....
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Electrostatic interactions in finite systems treated with periodic boundary conditions: Application to linear-scaling density functional theory
PublicationWe present a comparison of methods for treating the electrostatic interactions of finite, isolated systems within periodic boundary conditions (PBCs), within density functional theory (DFT), with particular emphasis on linear-scaling (LS) DFT. Often, PBCs are not physically realistic but are an unavoidable consequence of the choice of basis set and the efficacy of using Fourier transforms to compute the Hartree potential. In such...
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Visualizing Carotid Bodies With Doppler Ultrasound Versus CT Angiography: Preliminary Study
PublicationOBJECTIVE. The purpose of this article is to evaluate the utility of ultrasound in identifying carotid bodies (CBs) in patients with drug-resistant arterial hypertension. SUBJECTS AND METHODS. We enrolled 13 patients with drug-resistant hypertension into a trial for surgical CB excision. CT angiography (CTA) and Doppler ultrasound (DUS) of the cervical arteries were performed before surgery. CBs were identified in a blind manner...
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Pressure-induced flow processing behind the superior mechanical properties and heat-resistance performance of poly(butylene succinate)
PublicationWe propose a pressure-induced flow (PIF) processing method for the simultaneous enhancement of strength, toughness, and heat resistance of biodegradable poly(butylene succinate) (PBS). The pressure and temperature were systematically adjusted to optimize the tensile strength of PBS. Under the optimized processing conditions, the structured PBS was characterized by relatively high strength of 89.5 MPa, toughness of 21.4 kJ·m−2 ,...
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Searching for the primary metabolic alterations of polycystic ovary syndrome by application of the untargeted metabolomics approach
PublicationDespite a large number of studies, the pathogenesis of polycystic ovary syndrome (PCOS) still remains unexplained. In light of ambiguous observations reported in metabolomics, there is a need to carry out studies focusing on confirming the discriminating power of the proposed metabolomics biomarkers. Our research aimed to perform a validation study of metabolites detected in our previous study from serum samples, on the new set...
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Procesy i efektywność usuwania zanieczyszczeń z odcieków ze składowisk odpadów komunalnych w oczyszczalniach hydrofitowych
PublicationOczyszczanie odcieków z SOK jest jednym z najbardziej istotnych problemów ekologicznych na świecie. Odprowadzenie odcieków do oczyszczalni ścieków komunalnych jest przeważnie niemożliwe, ze względu na ich zmienną ilość oraz skład, bardzo wysokie stężenia ChZT i azotu amonowego, a także obecność trwałych zanieczyszczeń organicznych (TZO) oraz metali ciężkich. Najlepszym rozwiązaniem jest oczyszczanie wód odciekowych na terenie składowiska....
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Phase Change Thermal Energy Storage – The Experience of the Materials Preparation for the Specific Applications.
PublicationThermal energy storage and temperature stabilization is very important in many engineering applications. There are three kinds of thermal energy storage: sensible heat storage, latent heat storage and reversible chemical reaction heat storage. Phase change materials (PCM) absorb, store and release large amounts of energy in the form of latent heat, at constant temperature, called the transition temperature. The amount of heat...
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Local variability in snow concentrations of chlorinated persistent organic pollutants as a source of large uncertainty in interpreting spatial patterns at all scales
PublicationSingle point sampling, a widespread practice in snow studies in remote areas, due to logistical constraints, can present an unquantified error to the final study results. The low concentrations of studied chemicals, such as chlorinated persistent organic pollutants, contribute to the uncertainty. We conducted a field experiment in the Arctic to estimate the error stemming from differences in the composition of snow at short distances...
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The Research of the Contamination Levels present in Samples of Precipitation and Surface Waters Collected from the Catchment Area Fuglebekken (Hornsund, Svalbard Archipelago)
PublicationPersistent organic pollutants (POPs) are contaminants that may appear in polar regions. In present work surface water was collected from the main stream water in the Fuglebekken basin. The precipitationsamples was collected from the near area by Polish Polar Station in Hornsund. The present investigationreveals the results of the analysis of these samples for their total phenols, formaldehyde, TOC, PAHs and PCBs content. The...
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Optymalizacja parametrów procesu izolacji trwałych zanieczyszczeń organicznych z osadów dennych z uwzględnieniem formy ich występowania w środowisku wodnym
PublicationW pracy przedstawiono wyniki badań dotyczących optymalizacji metodyki oznaczania związków z grupy PCB w próbkach osadów dennych wykorzystując 3 rozpuszczalniki różniące się siłą elucji, polarnością, temperaturą wrzenia oraz toksycznością: dichlorometan, toluen, heksan oraz 3 techniki ekstrakcji związków z grupy PCB z próbek osadów, różniące się m.in czasem ekstrakcji oraz "czynnikiem" wspomagającym ekstrakcję. W wyniku przeprowadzonych...
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A screening of select toxic and essential elements and persistent organic pollutants in the fur of Svalbard reindeer
PublicationReindeers play an important role in the polar ecosystem, being long-lived sole vegetarians feeding on local vegetation. They can be used as a valuable bioindicator, helping us to understand contaminants’ impact on the polar terrestrial ecosystem. Still, scarce data exist from research in which polar herbivores (especially those from the European parts of the Arctic) were a major study subject for trace elements and persistent organic...
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Beeswax And Palmitic Acid Utilization With Heat Pipes For Electronics Cooling
PublicationThis paper presents an experimental study of heat pipes supported by phase change materials (PCMs) coated at their adiabatic sections in application for electronics cooling. The PCMs investigated in this research were palmitic acid and beeswax, the latter being considered as a more cost-effective alternative. The study focused on three powers: 20W, 25W, and 30W. The experimental results revealed that the incorporation of palmitic...
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Serum bisphenol A concentrations correlate with serum testosterone levels in women with polycystic ovary syndrome
PublicationThe aim of this study was to determine serum bisphenol A (BPA) concentrations using high performance liquid chromatography with tandem mass spectrometry (HPLC–MS/MS) in women with polycystic ovary syndrome (PCOS) (n=106, age range 18–40 yrs) and to evaluate its potential impact on their hormonal and metabolic profile. The control group consisted of age- and BMI-matched 80 eumenorrheic women with no clinical or biochemical hyperandrogenism....
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New empirical correlations for the viscosity of selected organic phase change materials
PublicationAlthough there are many methods and instruments for measuring viscosity, it is still difficult to determine a reliable value of the dynamic viscosity of complex chemicals such as paraffins and fatty acids. This is due to the complex and heterogeneous structure of these compounds in the case of commercial products. On the other hand, the measuring instrument should be selected very carefully, including its measuring principle and...
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Influence of the addition of citric acid on the physico-chemical properties of poly(sorbitol sebacate-co- butylene sebacate)
PublicationThe article presents the results of the physicochemical properties of poly(sorbitol sebacate- co-butylene sebacate) (PSBS) obtained with 0.25; 0.5; 0.75; 1 mol of citric acid (KC). It was shown that PSBS obtained with 0.25 and 0.5 mol KC is characterized by the most optimal mechanical and thermal properties. As a result of the study, it was found that the use of sorbitol and citric acid allows obtaining ester materials with...
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Solar light driven degradation of textile dye contaminants for wastewater treatment – studies of novel polycationic selenide photocatalyst and process optimization by response surface methodology desirability factor
PublicationThe unplanned anthropogenic activities and raced industrial revolution detrimentally causes serious threat to terrestrial and aquatic life. A high discharge of wastewater from industries using dyes affects living organisms and the environment. This paper presents studies on polycationic selenides (PCS) synthesized by hydrothermal methods for photocatalytic degradation of dyes. The synthesized PCS were confirmed by various characterization...
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Identyfikacja nieparametryczna systemów farmakokinetycznych metodą funkcji korelacji.
PublicationW pracy omówiono metodę funkcji korelacji, przedstawiono jej ograniczenia numeryczne oraz pobudzenia zapewniające maksymalną dokładność estymat odpowiedzi impulsowej w tej metodzie: szum biały oraz pobudzenia PRBS.
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Opinia techniczna torów na bocznicy kolejowej ANWIL S.A. we Włocławku. Nawierzchnia kolejowa z szyn typu S42 na podkładach strunobetonowych typu PBS-1, INBK 3, INBK 4, INBK 7, INBK 9 i na podkładach drewnianych typu IIIB z przytwierdzeniem pośrednim typu K
PublicationOpinia techniczna torów na bocznicy kolejowej ANWIL S.A. we Włocławku dotycząca oceny nawierzchni kolejowej z szyn typu S42 na podkładach strunobetonowych typu PBS-1, INBK 3, INBK 4, INBK 7, INBK 9 i na podkładach drewnianych typu IIIB z przytwierdzeniem pośrednim typu K
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Opinia techniczna torów na bocznicy kolejowej ANWIL S.A. we Włocławku. Nawierzchnia kolejowa z szyn typu S49 na podkładach strunobetonowych typu PBS-1, INBK 3, INBK 4, INBK 7, INBK 9 i na podkładach drewnianych typu IIB z przytwierdzeniem pośrednim typu K
PublicationOpinia techniczna torów na bocznicy kolejowej ANWIL S.A. we Włocławku dotycząca nawierzchni kolejowa z szyn typu S49 na podkładach strunobetonowych typu PBS-1, INBK 3, INBK 4, INBK 7, INBK 9 i na podkładach drewnianych typu IIB z przytwierdzeniem pośrednim typu K
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Monitoring of organic pollutants in coastal waters of the Gulf of Gdańsk, Southern Baltic.
PublicationPrzedstawiono zmiany zawartości zanieczyszczeń organicznych (np. VOC, PAH, PCB, chlorofenoli) w wodach Zatoki Gdańskiej na przestrzeni 5-ciu lat. Zawartość VOX i VOC zmieniała się od kilku ngdm-3 do kilkuset ngdm-3, podczas gdy zawartość chlorofenoli fenoksykwasów była na poziomie kilku ngdm-3. W większości próbek nie wykryto PCB.
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Historical records of organic pollutants in sediment cores
PublicationAnalyses of sediment core samples are primary sources of historical pollution trends in aquatic systems. Determining organic compounds, such as POPs, in the dated sediments enables the estimation of their temporal concentration changes and the identification of the contaminant origin in local regions. Wars, large-scale fires, economical transitions, and bans on certain chemicals are reflected in the sediment organic compound concentrations....
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Advanced Hysteretic Model of a Prototype Seismic Isolation System Made of Polymeric Bearings
PublicationThe present paper reports the results of acomprehensive study designed to verify the effectiveness of an advanced mathematical model in simulating the complex mechanical behaviour of a prototype seismic isolation system made of polymeric bearings (PBs). Firstly, in order to construct the seismic bearings considered in this research, a specially prepared flexible polymeric material with increased damping properties was employed....
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Specjacja fizyczna i mobilność analitów z grupy wielopierścieniowychwęglowodorów aromatycznych i polichlorowanych bifenyli na granicy fazosad denny-woda
PublicationW pracy przedstawiono istotne zagadnienia związane z lokalizacją isposobami wiązania zanieczyszczeń w osadach dennych orazkonsekwencjami tego dla opracowywanych metodyk analitycznych orazstanu środowiska. Na podstawie przeprowadzonych badań własnych oraz studiów literaturowych uzyskano następujące efekty:• określono wpływ sposobu dodawania roztworu zawierającego wzorcewewnętrzne do próbek osadów oraz przebieg procesu ekstrakcji...
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Photovoltaic module temperature stabilization with the use of phase change materials
PublicationThe worldwide growth of photovoltaics (PVs) has formed an exponential curve for more than four decades. During this period of time, PVs have evolved from a pure niche market of small-scale applications towards becoming a mainstream electricity source. The influence of temperature on the electrical parameters of crystalline silicon solar cells and solar modules is well described in the literature. In order to diminish these effects,...
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Wideband Modeling of DC-DC Buck Converter with GaN Transistors
PublicationThe general wideband modeling method of the power converter is presented on the example of DC-DC buck converter with GaN High Electron Mobility Transistors (HEMT). The models of all basic and parasitic components are briefly described. The two methods of Printed Circuit Board (PCB) layout parameter extraction are presented. The results of simulation in Saber@Sketch simulation software and measurements are compared. Next, the model...
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Contaminants in airport runoff water
PublicationDespite the many positives ensuing from the rapid expansion of the air transport sector, airport operations as a whole are a substantial source of environmental pollution.Increases in aviation developments have serious consequences on the surrounding air, soil and water bodies like lakes, rivers and ground water. The present work deals with the determination of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls...
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Contaminants in airport runoff water in the Vicinities of Two International Airports in Poland
PublicationThe general aim of the study was to evaluate environmental quality associated with the operations (combustion of fuels, cleaning of aircraft and airport aprons, aircraft, ground vehicle maintenance and repairs, fuelling operations, de/anti-icing operations) of international airports located in central and northern of Poland. These two monitoring areas were set up to monitor PAHs, PCBs, formaldehydes, phenols, detergents (cationic,...
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Exploring the interfacial effects at the ETL/perovskite boundary in the semitransparent perovskite solar cells
PublicationThe recent focus has been made on the perovskite solar cells (PSCs) with an inverted configuration, where substantial improvements have been already achieved. However, the p–i–n structure needs a buffer layer for most of the configurations to modify the work-function of a deposited electrode. Additionally and very importantly, such a layer can also serve as a protective film that improves a stability of solar cells. Here, we study...
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Featuring Semitransparent p–i–n Perovskite Solar Cells for High-Efficiency Four-Terminal/Silicon Tandem Solar Cells
PublicationTwo issues need to be resolved when fabricating p–i–n semitransparent perovskite solar cells (ST-PVSCs) for four-terminal (4 T) perovskite/silicon tandem solar cells: 1) damage to the underlying absorber (MAPbI3), electron transporting layer ([6,6]-phenyl-C61-butyric acid methyl ester, PCBM), and work function (WF) modifier (polyethylenimine, PEI), resulting from the harsh sputtering conditions for the transparent electrodes (TEs)...
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Miniaturised analytical procedure of determining polycyclic aromatic hydrocarbons and polychlorinated biphenyls in bottom sediments
PublicationOpisano metodę oznaczania bardzo niskich stężeń polichlorowanych bifenyli w obecności wysokich zawartości wielopierścieniowych węglowodorów aromatycznych. Analizie techniką GC-MS poddawany jest ekstrakt z 1 g próbki osadu. Jako standardy wewnętrzne zastosowano Naftalen-d8, benzo[a]antracen-d12 i PCB 209. Średni odzysk standardów przedstawiał się następująco: 65, 55 i 60% odpowiednio. Do izolacji frakcji PCB stosowano niekomercyjne...
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Stanowisko do analizy sygnałów przesyłanych w kanale hydroakustycznym
PublicationOpisano stanowisko badawcze, za pomocą którego wyznaczano odpowiedzi kanału hydroakustycznego na pobudzenie sygnałem modulowanym ciągiem pseudoprzypadkowym PRBS (Pseudo Random Binary Sequence) oraz przeprowadzono eksperymenty z transmisją danych z rozpraszaniem widma metodą bezpośrednią. Omówiono wyniki badań w warunkach laboratoryjnych oraz w jeziorze i basenie portu morskiego. Badania wykonano w warunkach statycznych.
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Toczenie wykończeniowe powierzchni otworów w stanie utwardzonym
PublicationW pracy przedstawiono studium przypadku toczenia wykończeniowego powierzchni otworu w stanie utwardzonym (60+/-2HRC). Obróbka ta jest alternatywną technologią do obróbki wykończeniowej szlifowaniem otworów kół zębatych. Wyniki przeprowadzonych badań wykazały, że toczenie za pomocą narzędzi z ostrzami z PCBN (polikrystaliczny regularny azotek boru) zapewnia spełnienie wymagań konstrukcyjnych, co do jakości wytwarzanych wyrobów.
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Selected concentration techniques for gas chromatographic analysis of environmental samples
PublicationThe paper describes the role and tasks of environmental analysis and monitoring. It emphasises the leading role played by gas chromatography, especially when coupled with suitable sample preparation. This is demonstrated by some literature evidence and mainly by the author's original work on the design of sample preparation apparatus and development of GC-based methods of determination of a wide variety of organic pollutants in...
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A Numerical Model Study on Grasse River Ice Control Structures
PublicationIce jams in the Grasse River have caused the erosion of capping material designed to prevent the resurfacing of the bed sediment in the PCB-contaminated area. Two in-stream ice-control structures are proposed to avoid the jam-induced erosion of the capping material. These two ice-control options are a pier-type ice-control structure and a reconstruction of a small hydropower dam upstream of the capping site. A numerical model study...