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Search results for: Environmental analysis
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The influence of humic substances in treated sewage on the quality of surface waters
PublicationAt present the evaluation of WWTP effectiveness is based upon organic matter and nutrients removal. Recently it was found out that sewage treatment leads to formation of resistant to biochemical degradation organic compounds, similar to humic acids. The humic acids formed during sewage treatment process play diversified functions when discharged to surface waters - for instance they can act as carriers of hydrophobic organic pollutants...
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Model-Based Evaluation of N2O Production Pathways in the Anammox-Enriched Granular Sludge Cultivated in a Sequencing Batch Reactor
PublicationA mechanistic model was developed as an extension of the Activated Sludge Model No. 1 to describe three nitrous oxide (N2O) production pathways in a laboratory-scale anammox-enriched granular sequencing batch reactor. Heterotrophic denitrification and two processes mediated by ammonia oxidizing bacteria (AOB), that is, ammonia (NH4+) oxidation via hydroxylamine (NH2OH) and autotrophic denitrification, were considered. A systematic...
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Roofing Materials as Pollution Emiters - Concentration Changes During Runoff
PublicationThe influence of roofing material on concentration of pollutants in roof runoff waters and changes of pollution concentration in time were investigated. In field studies four roofing material types were taken into consideration - ceramic tile, bituminous membrane, asbestos tile and zinc sheeting. Samples were collected since November 2007 to March 2008, anions, cations, metals, PAHs, pesticides and PCB were determined. The existence...
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Technologies for deodorization of malodorous gases
PublicationThere is an increasing number of citizens’complaints about odor nuisance due to production or service activity. High socialawareness imposes pressure on entrepreneurs and service providers forcing them to undertake effective steps aimed at minimi-zation of the effects of their activity, also with respect to emission of malodorous substances. The article presents informationabout various technologies used for gas deodorization....
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An improvement of body surface area formulas using the 3D scanning technique
PublicationObjectives: Body surface area (BSA) is one of the major parameters used in several medical fields. However, there are concerns raised about its usefulness, mostly due to the ambiguity of its estimation. Material and Methods: Authors have conducted a voluntary study to investigate BSA distribution and estimation in a group of 179 adult people of various sex, age, and physique. Here, there is provided an extended analysis of the...
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Multiresidue Methods for Determination of Currently Used Pesticides in Fruits and Vegetables Using QuECHERS Technique
PublicationApplied all over the world, pesticides are some of the most common pollutants of the environment because of their stability, mobility, their consequent long-term adverse effects on living organisms in general and human health in particular. For these reasons it is essential to monitor and analyse pesticide residues in the fruits and vegetables. The analysis of food samples for the presence of pesticides causes a lot of difficulties...
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Indoor air quality in public utility environments-a review
PublicationIndoor air quality has been the object of interest for scientists and specialists from the fields of science such as chemistry, medicine and ventilation system design. This results from a considerable number of potential factors, which may influence the quality of the broadly understood indoor air in a negative way. Poor quality of indoor air in various types of public utility buildings may significantly affect an increase in the...
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Application of the Mathar method to identify internal stress variation in steel as a welding process result
PublicationThe paper deals with the method to identify internal stresses in two-dimensional steel members. Steel members were investigated in the delivery stage and after assembly, by means of electric-arc welding. In order to perform the member assessment two methods to identify the stress variation were applied. The first is a non-destructive measurement method employing local external magnetic field and to detecting the induced voltage,...
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Chemical composition of lipids isolated from selected organs and tissues of the raccoon dog (Nyctereutes procyonoides)
PublicationOur paper presents a qualitative analysis of particular lipid classes (phospholipids, triacylglycerols, cholesterol, free fatty acids) isolated from the tissues of raccoon dogs harvested in northeastern Poland. In all examined tissues (except for the liver) the dominant group of lipids were triacylglycerols. The amounts of lipids representing the other classes depended on the kind of tissue from which the fat was isolated. The...
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The interplay between dopant and a surface structure of the photocatalyst – The case study of Nb-doped faceted TiO2
PublicationAnatase nanoparticles, exposing the majority of the {0 0 1}, {1 0 0} and {1 0 1} facets were synthesized and doped with different niobium amount to investigate the self-trapping of the excess electrons and resulting photocatalytic activity. Photocatalyst structure and presence of excess electrons inside the obtained Nb-doped anatase samples was confirmed by the combination of structural and spectroscopic analyses. Only for the...
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Experimental Testing of Innovative Cold-Formed "GEB" Section / Badania Eksperymentalne Innowacyjnego Kształtownika Giętego Na Zimno Typu „Geb“
PublicationOne of the major advantages of light gauge steel structures made of cold-formed steel sections is their low weight, so manufacturers are increasingly using the possibilities of those sections for the production of typical single-storey steel structures systems. Well known profiles, such as Z, C and the so called hat sections that have been studied and described in the literature, are used mainly as purlins or truss components....
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Spetiation of organic matter in Vertical Flow Constructed Wetlands
PublicationThe object of the research were VFCWs which are a component of biological treatment of two hybrid hydrophyte systems located in Wieszyno and Wiklino, close to Słupsk, Poland. The facilities that are subject to analyses are unified in terms of structure (filtration material, depth of the bed and time of operation), but they differ in organic matter load, amounting respectively to: 8.0 gCOD/m2day and 31.0 gCOD/m2day.The intensity...
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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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A new strategy for PET depolymerization: Application of bimetallic MOF-74 as a selective catalyst
PublicationLarge-volume production of poly(ethylene terephthalate) (PET), especially in the form of bottles and food packaging containers, causes problems with polymer waste management. Waste PET could be recycled thermally, mechanically or chemically and the last method allows to obtain individual monomers, but most often it is carried out in the presence of homogeneous catalysts, that are difficult to separate and reuse. In view of this,...
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Synthesis, characterization, and application of 2D/2D TiO2-GO-ZnFe2O4 obtained by the fluorine-free lyophilization method for solar light-driven photocatalytic degradation of ibuprofen
PublicationIn this study, we report the potential of 2D/2D TiO2- GO-ZnFe2O4 photocatalyst obtained using the fluorine-free lyophilization technique for the degradation of ibuprofen belonging to the group of active pharmaceutical ingredients (API). The improved ibuprofen degradation under simulated solar light was achieved in the presence of a composite of 2D TiO2 combined with GO and embedded ZnFe2O4, which additionally provides superparamagnetic...
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Optimization of the Aeration Strategies in a Deammonification Sequencing Batch Reactor for Efficient Nitrogen Removal and Mitigation of N2O Production
PublicationIn deammonification systems, nitrite-oxidizing bacteria (NOB) suppression and nitrous oxide (N2O) mitigation are two important operational objectives. To carry out this multivariable analysis of response, a comprehensive model for the N cycle was developed and evaluated against experimental data from a laboratory-scale deammonification granular sludge sequencing batch reactor. Different aeration strategies were tested, and the manipulated...
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Incorporation of the complete ammonia oxidation (comammox) process for modeling nitrification in suspended growth wastewater treatment systems
PublicationThe newly discovered process complete ammonia oxidation (comammox) has changed the traditional under-standing of nitrification. In this study, three possible concepts of comammox were developed and incorporated as part of an extended two-step nitrification model. For model calibration and validation, two series of long-term biomass washout experiments were carried out at 12 ◦C and 20 ◦C in a laboratory sequencing batch reactor....
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Flood Routing by the Non-Linear Muskingum Model: Conservation of Mass and Momentum
PublicationIn this paper, the conservative properties of the Muskingum equation, commonly applied to solve river flood routing, are analysed. The aim of this analysis is to explain the causes ofthe mass balance error, which is observed in the numerical solutions of its non-linear form. The linear Muskingum model has been considered as a semi-discrete form of the kinematic wave equation and therefore it was possible to derive its two non-linear...
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Multi-objective optimization of water quality, pumps operation, and storage sizing of water distribution systems
PublicationA multi-objective methodology utilizing the Strength Pareto Evolutionary Algorithm (SPEA2) linked to EPANET for trading-off pumping costs, water quality, and tanks sizing of water distribution systems is developed and demonstrated. The model integrates variable speed pumps for modeling the pumps operation, two water quality objectives (one based on chlorine disinfectant concentrations and one on water age), and tanks sizing cost...
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Annual variability of heavy metal content in Svalbard reindeer faeces as a result of dietary preferences
PublicationDuring both winter and summer, Svalbard reindeer selectively feed on different types of vegetation that are not only a source of nutritional value, but also a place of heavy metal accumulation. In the present study, the content of cadmium, chromium, copper, iron, lead, nickel, manganese, and zinc in reindeer excrement was measured. The main aims were to determine the seasonal content of several heavy metals in Svalbard reindeer...
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Preparation and characterization of monometallic (Au) and bimetallic (Ag/Au) modified-titania photocatalysts activated by visible light
PublicationThe Au-TiO2 and Ag/Au-TiO2 nanoparticles have been prepared using a water-in-oil microemulsion system of water/AOT/cyclohexane and water/Triton X-100/cyclohexane. The obtained photocatalysts were subsequently characterized by a BET method, DRS spectroscopy, X-ray photoelectron emission spectroscopy (XPS), scanning transmission electron microscopy (STEM) and X-ray powder diffraction analysis (XRD). For gold-doped titanium (IV) oxide...
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Application of passive sampling technique in monitoring research on quality of atmospheric air in the area of Tczew, Poland.
PublicationThis paper presents the results of atmospheric air quality research in Tczew (adjacent to the Vistula River) on the content of BTEX compounds. Analytical procedure applied during the sampling of the analytes from the air used the passive sampling technique (diffusive passive sampler, Radiello®). For determination of BTEX compounds in atmospheric air, two-stage thermal desorption technique combined with gas chromatography (TD-GC-FID)...
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Landscape protection in environmental impact assessment in Poland. The exa- mple of a Gdańsk fortification system which is threatened by transport in- vestments. J. Transdiscipl. Environ. Stud. [online]**2002 vol. 1 nr 2 [dos- tęp: 2002.12.20] s. 1-18, 3 rys. bibliogr. 11 poz. Dostępny w Internecie: http://www.journal-tes.dk/. ISSN 1602-2297 Ochrona krajobrazu w Ocenach Oddziaływania na Środowisko w Polsce -na przy- kładzie fortyfikacji gdańskich zagrożonych inwestycjami komunikacyjnymi.
PublicationSpecyficzny przypadek potencjalnego zagrożenia dla fortyfikacji nowożytnych Gdańska, spowodowanego nowymi, planowanymi inwestycjami komunikacyjnymi jesttłem dla ukazania możliwości wykorzystania procedury Oceny Oddziaływania na Środowisko dla ochrony i kształtowania krajobrazu.
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cDNA fingerprint from the hepatopancreatic glands of pond snails (Lymnaea stagnalis) exposed to benzo[a]pyrene
PublicationIdentification of differentially expressed genes that could be potentially used as biomarkers of PAH exposure of common invertebrate animal (like freshwater snail) would be a valuable resource for investigators interested in toxicology and biomonitoring of aquatic environments. Therefore, the aim of this research was to investigate effects of waterborne benzo[a]pyrene (B[a]P) exposure on mRNA expression in the pond snail’s (Lymnaea...
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Impact of influent wastewater quality on nitrogen removal rates in multistage treatment wetlands
PublicationNitrogen removal in treatment wetlands is influenced by many factors, and the presence of electron donors (biodegradable organic matter) and electron acceptors (nitrate ions) is the main limiting one; for obtaining these conditions, multistage treatment wetlands (MTWs) are required, where an extensive nitrification can be obtained in the first stages under aerobic conditions leaving then to the following anoxic/anaerobic stages...
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Methods of Assessment of Metal Contamination in Bottom Sediments (Case Study: Straszyn Lake, Poland)
PublicationThe concentrations of six metals (Zn, Cu, Pb, Ni, Cr, and Cd) were investigated in bottom sediments of Straszyn Lake (North Poland). This study was designed to determine a total content of metals and to assess their mobility and bioavailability. The sequential extraction was used to fractionate metals into five fractions: exchangeable, bound to carbonates, bound to Fe–Mn oxides, bound to organic matter, and residual. The evaluation...
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An optimal designed experiment for the alkaline hydrolysis of feather keratin
PublicationFeathers, burdensome waste from the poultry industry, can be a cheap source of keratin, a protein with excellent physico- chemical, biological, and mechanical properties. Acid and alkaline hydrolyses are usually adopted for isolation of keratin from its natural resources. This study aimed at assessing the statistically significant effect of input variables in the alkaline hydrolysis of keratin from chicken feathers on the process...
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A risk analysis of winter navigation in Finnish sea areas
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Reactive deposition of TiNx layers in a DC-magnetron discharge
PublicationTiNx layers have been deposited in 'balanced mode' and 'unbalanced mode' of a reactive DC-magnetron plasma (carrier gas argon, reactive gas nitrogen) under different conditions. Discharge power and reactive gas flow have been varied. The layers have been examined by X-ray photoelectron spectroscopy (XPS), X-ray reflectometry (XR), and spectroscopic ellipsometry (SE). The results of the layer analyses were combined with plasma investigations...
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Post-failure fracture surface analysis of notched steel specimens after bending-torsion fatigue
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Effect of multiaxial bending-torsion loading on fracture surface parameters in high-strength steels processed by conventional and additive manufacturing
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Fractal analysis of the bending-torsion fatigue fracture of aluminium alloy
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Thermal subjective sensations of motorcyclists
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A PAIR OF PERFECTLY CONDUCTING DISKS IN AN EXTERNAL FIELD
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Bisquare robust polynomial fitting method for dimple distortion minimization in surface quality analysis
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Proposal of frequency‐based decomposition approach for minimization of errors in surface texture parameter calculation
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Threat/risk assessment tool to assess vulnerability of Polish cities to Russian attacks
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Non-destructive testing of industrial structures with the use of multi-camera Digital Image Correlation method
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Thermal properties of poly(vinyl chloride)/polyurethane blends
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Application of the DSC analysis of thermoplastic polyurethane elastomers to a comparative study of their technological properties
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Primary and secondary crystallization of poly(ethylene adipate)
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Dynamic mechanical thermal analysis of polyamide 6/thermoplastic polyurethane blends
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Thermal properties of polyamide 6/polyurethane blends
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Glass transition temperatures of polyurethane-urea elastomers based on N, N′-ethylenethiourea and N, N′-ethyleneurea as chain extenders
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Crystallization kinetics of poly(ethylene adipate) investigated by differential scanning calorimetry
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First-order impulsive functional differential equations
PublicationPraca dotyczy problemów istnienia rozwiązań i kwazi-rozwiązań dla równań różniczkowych rzędu pierwszego z impulsami i nieliniowymi warunkami brzegowymi. Operator występujący w zagadnieniu jest typu opóźnionego. Badano również nierówności różniczkowe z impulsami związane z zagadnieniem wyjściowym. Otrzymane wyniki zilustrowano na przykładach.
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Stable and unstable bifurcation in the von Karman problem for a circular plate
PublicationW niniejszej pracy badamy równania von Karmana dla cienkiej, sprężystej, kołowej płyty, która znajduje się na sprężystym podłożu, pod działaniem sił ściskających wzdłuż swojego brzegu.Stosując metody analizy nieliniowej, dowodzimy istnienia stabilnychi niestabilnych punktów bifurkacji w zbiorze rozwiązań badanych równań.
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Systems of differential equations with a singular matrix
PublicationPraca dotyczy układów równań różniczkowych z macierzą osobliwą. Szczególnymi przypadkami takich układów są równania różniczkowo-algebraiczne. Korzystając z odpowiedniej nierówności różniczkowej dla układów równań i metody quasi linearyzacji pokazano, iż odpowiednie monotoniczne ciągi są zbieżne do rozwiązania naszego problemu i jest to zbieżność kwadratowa. O funkcji f występującej po prawej stronie zagadnienia zakładano...
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Differential inequalities with initial time difference.
PublicationUzyskano pewne wyniki porównawcze pomiędzy rozwiązaniami nierówności różniczkowych startujących z różnych punktów początkowych. O nieliniowej funkcji f (związanej z zagadnieniem) zakładano jednostronny warunek Lipschitza. Podano pewne zastosowanie otrzymanych wyników. Sformułowano też pewne warunki dotyczące stabilności.
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Analysis of Interspike-Intervals for the General Class of Integrate-and-Fire Models with Periodic Drive
PublicationWe study one-dimensional integrate-and-fire models of the general type x˙=F (t, x) and analyze properties of the firing map which iterations recover consecutive spike timings. We impose very week constraints for the regularity of the function F (t, x), e.g. often it suffices to assume that F is continuous. If additionally F is periodic in t, using mathematical study of the displacement sequence of an orientation preserving circle...