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Search results for: CONSTRUCTED WETLAND HORIZONTAL FLOW WASTEWATER TREATMENT BIOGENIC COMPOUNDS TECHNOLOGICAL RELIABILITY LONG-TERM OPERATION
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Experimental Investigations of Forced Convection of Nanofluids in Smooth, Horizontal, Round Tubes: A Review
PublicationA comprehensive review of published works dealing with experimental studies of forced convection heat transfer of nanofluids is presented. The survey is limited to straight, smooth, and round tubes. Moreover, only mono nanofluids exhibiting Newtonian behaviour are considered. Works on experimental research of forced convection in tubes are presented in a chronological order in the first part of the article. In this part, attention...
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OBTAINING FLUID FLOW PATTERN FOR TURBINE STAGE WITH NEURAL MODEL.
PublicationIn the paper possibility of applying neural model to obtaining patterns of proper operation for fluid flow in turbine stage for fluid-flow diagnostics is discussed. Main differences between Computational Fluid Dynamics (CFD) solvers and neural model is given, also limitations and advantages of both are considered. Time of calculations of both methods was given, also possibilities of shortening that time with preserving the accuracy...
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Practical aspects of design and operation of amphibious craft for rescue purposes
PublicationThe paper presents the selected problems of design and operation of amphibious craft for rescue purposes. The result of research on the amphibious rescue units allowed formulating the general conclusions with respect to the proper selection of the main design parameters, program of model tests and full scale trials for the amphibious craft. The most important design problems related to the water characteristics are presents and...
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Stabilization of Solid Residues Obtained During Sewage Sludge Thermal Treatment
PublicationCurrently wastewater treatment plants are still dealing with the problem of ecological management of sewage sludge. Nowadays, thermal utilization is considered the most eco-friendly way of processing excess sludge. However, during mentioned process, fractions of ashes and dusts are generated. Such wastes, especially dusts fraction, can be potentially harmful for the environment and wastes should be stabilized before further management....
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Subsoil degradation effect in reliability analysis of the jack-up platform structure
PublicationStructural reliability analysis is considered, by FORM and SORM applied to a certain idealized soil-platform structure interaction problem due to cyclic water wave and wind loads. Wave and wind loads are random variables, whereas dead load is deterministic. Load parameters are typical for storm conditions in the Baltic Sea. The soil-structure interaction is idealized as a set of linear translational and rotational springs. Due...
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Determination of biogenic amines in processed and unprocessed mushrooms from the Polish market
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REVIEW ON COMPETITION АОB AND NОВ AS AN IMPORTANT ELEMENT FOR COST EFFECTIVE METHODS OF REMOVING NITROGEN FROM WASTEWATER
PublicationThe aim of this paper is analysis of process principles and possible factors used to induce inhibition of nitrite oxidation by NOB (Nitrite Oxidizing Bacteria) which could be obtained during not very well understood processes: so called “shortcut” or “partial” nitrification as well deammonification, by qualitative/quantitative studies of AOB (Ammonium Oxidizing Bacteria) and NOB populations in activated...
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On a comparison principle and the uniqueness of spectral flow
PublicationThe spectral flow is a well-known quantity in spectral theory that measures the variation of spectra about 0 along paths of selfadjoint Fredholm operators. The aim of this work is twofold. Firstly, we consider homotopy invariance properties of the spectral flow and establish a simple formula which comprises its classical homotopy invariance and yields a comparison theorem for the spectral flow under compact perturbations. We apply...
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The role of colloidal and particulate organic compounds in idenitrification and EBPR occurring in a full-scale activatedsludge system
PublicationThe aim of this study was to determine the immediate effects of slowly biodegradable substrates on the denitrification capability andphosphate release/uptake interactions for a full-scale biomass process from the ''Wschod'' wastewater treatment plant (WWTP) in Gdansk (Poland). Since it is hard to distinguish the slowlybiodegradable substrate in a direct way, a novel procedure based on batch experiments was developed and implemented....
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Interaction Between Storm Water Conduit Flow and Overland Flow for Numerical Modelling of Urban Area Inundation
PublicationNowadays we can observe increasing frequency of inundations in cities. This makes accurate predicting of inundations more important than ever. Numerical modeling of this issue requires complex approach with simultaneous calculations of pipe flow and surface flow. In this paper, after a short review of known methods used for solving pipe and surface flow, we will try to answer the question if presented methods would be sufficiently...
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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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Diagnosing marine turbine engines through energy characteristics of their flow section
PublicationThe aim of the performed research was to develop of diagnostic method of the flow section of a marine turbine combustion engine based on the level of delamination of its energy characteristics. The here adopted diagnostic model provides for a formulation of the evaluation of the technical conditions based on the measurements of the parameters of the thermodynamic medium in the characteristic control cross-sections of the engine...
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Flow Maps and Flow Patterns of R1233zd(E) in a Circular Minichannel at Low, Medium and High Values of Saturation Pressure
PublicationThere is a gap in knowledge regarding the flow pattern of low-boiling working fluids in the range of high saturation temperatures (above 120°C) and medium and high reduced pressures (0.5-0.9). Data are present in the literature for similar values of reduced pressures, but for lower values of saturation temperature. This is due to the existing refrigeration applications of these working fluids. At high values of reduced pressure,...
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Simplified Numerical Model for Transient Flow of Slurries at Low Concentration
PublicationRapid transients are particularly dangerous in industrial hydro-transport systems, where solid-liquid mixtures are transported via long pressure pipelines. A mathematical description of such flow is difficult due to the complexity of phenomena and difficulties in determining parameters. The main aim of the study was to examine the influence of the simplified mixture density and wave celerity description on satisfactory reproduction...
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Implementation of the digital receiver in multibeam long-range sonar
PublicationThe article presents the implementation of a digital receiver in multibeam long - range sonar. Developed by the authors of the article, the implementation was part of sonar modernisation on large Polish Navy ships. The article explains the structure of the receiver, its design details and requirements affecting the architecture. The technical solutions regarding the equipment and signal processing algorithms for determining receiving...
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The effect of anionic surfactant concentration on activated sludge condition and phosphate release in biological treatment plant
PublicationThis paper discusses the influence of a wide range of anionic surfactant concentrations on activated sludge. Linear alkylbenzene sulphonate (LAS) was chosen as an example of a commonly used anionic surfactant. The fate of the surfactant during biological treatment of wastewater was tested. The effect of surfactant on glucose and starch removal was studied.
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Thermal and technological aspects of double face grinding of Al2O3 ceramic materials
PublicationDouble 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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Reliability of acicular grindable thermocouples for transient temperature measurements at sliding contacts
PublicationAcicular grindable thermocouples represent an interesting and prospective technique of temperature measurements at sliding contacts. This study aimed at the investigation of their reliability and accuracy as applied to the friction materials of various classes in contact with steel. The tests were conducted on a pin-on-disc tribometer under stationary and transient regimes. The experimental results were validated by comparing the...
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Technological progress and its contribution to economic development
PublicationArtykuł stanowi analizę zależności pomiędzy poziom rozwoju i wdrożenia technologii informacyjnych i komunikacyjnych w kraju z poziomem jego rozwoju gospodarczego.
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Heat Transfer During Pool Boiling of Water, Methanol and R141b on Porous Coated Horizontal Tube Bundles
PublicationThis paper presents the results of experimental investigation of water, methanol and R141b refrigerant boiling on horizontal porous coated tube bundles supposed to represent a flooded-type evaporator. Experiments were carried out for a bundle of 19 tubes in triangular layout for two pitch-to-diameter ratio values – 1.7 and 2.0 – in atmospheric and sub-atmospheric pressure conditions. Average heat transfer coefficients – both local,...
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Determination of short-chain monocarboksylic acids in cattle farm and dairy industry wastewater
PublicationThe paper describes application of various techniques to determine short-chain monocarboksylic acids (SCMAs) in samples from the successive steps from milk production: from wastewater from cattle farm to wastewater from dairy industry. Each technique of sample preparation is followed by gas chromatographic analysis.
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Numerical Simulations for Transonic Flow in Control Valve
PublicationResults of numerical simulations for transonic flow in control valve are presented. The valve is the main part of an adaptive pneumatic shock absorber. Flow structure in the valve domain and the influence of the flow non-uniformity in the valve on a mass flow rate is investigated. Numerical simulation results are compared with experimental data.
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Application of semi-Markov processes for evaluation of diesel engines reliability with regards to diagnostics
PublicationThe paper presents semi-Markov models of technical state transitions for diesel engines, useful for determination of their reliability, as a result of the conducted statistical empirical studies. Interpretation of technical states provided for this sort of engines refers to ship main engines, i.e. engines employed in propulsion systems of sea-going ships. The considerations recognize diesel engine as a diagnosed system (SDN), of...
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Trajectory planning for Service Ship during emergency STS transfer operation
PublicationIn this paper trajectory for approaching during emergency STS transfer operation with oil spill is considered as a sequence of navigation manoeuvres in specific navigational environment. The designed way points - ship positions and speed are determined as reference values to support navigator in decision making during steering and to mitigate the risk of collision which mostly results from exceeding the speed limit of approaching....
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Flow Analysis of a Kaplan Turbine
PublicationThis monograph is a guide to a method of experimental and numerical flow investigations for Kaplan - type turbines. The numerical calculations were compared with the test results of the model Kaplan turbine. The tests were carried out on the model test rig in the Gdańsk University of Technology. The turbine has been thoroughly experimentally investigated, resulting in the identification of optimum setting combination of the stator...
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Zastosowanie ultrafiltracji do dezynfekcji i doczyszczania ścieków oczyszczonych = Ultrafiltration process in disinfection and advanced treatment of tertiary treated wastewater
PublicationW pracy przedstawiono wyniki badań nad ultrafiltracją komunalnych ścieków oczyszczonych. Ustalono, że ultrafiltracja jest skuteczną metodą dezynfekcji. W permeacie obserwowano jedynie pojedyncze komórki bakterii wskaźnikowych. Proces ultrafiltracji umożliwia dalszą poprawę parametrów fizyczno-chemicznych ścieków oczyszczonych. Najlepiej usuwane były mętność oraz fosfor ogólny, dobre efekty uzyskano w usuwaniu ChZT oraz BZT5, w...
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Usuwanie struwitu z rurociągów w oczyszczalni ścieków komunalnych = Struvite removal from pipelines in municipal wastewater treatment plant
PublicationStruwit MgNH4PO4 .6H2O jest minerałem występującym w przyrodzie. Minerał ten może powstawać również w organizmie człowieka oraz zwierząt jako kamień nerkowy. W wielu oczyszczalniach ścieków struwit wytrąca się m.in. podczas odprowadzania cieczy nadosadowej z komór fermentacyjnych. Powoduje to szybkie zmniejszanie się przekroju czynnego rurociągów i konieczność ich wymiany lub usuwania powstałego osadu. Ponadto, powstający osad...
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EXHAUST TEMPERATURE MEASUREMENTS OF THE MARINE TURBOCHARGED DIESEL ENGINES IN OPERATION
PublicationThe article presents the selected metrology issues concerning the exhaust temperature of the turbocharged marine engines during operation. The special concern has been paid on existing disturbances as well as thermodynamical interpretation of the recorded measurement signal. A diagnostic informativeness of the standard exhaust temperature’s measurements has worked out while the engine runs in steady states has been also considered...
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Co-operation with local stakeholders: a crucial element of urban design
PublicationIn this article,the authors endeavour to illustratethe evolution of the role of local stakeholder in teaching urban planning by example of selected experiences in the Faculty of Architecture atGdańsk University of Technology(FA-GUT), Gdańsk, Poland. The timeframe covers the period from the political breakthrough in 1989 to the present. The background is composed of the social, economic and legal changes that have...
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DETERMINATION OF SURFACTANTS IN ENVIRONMENTAL SAMPLES. PART II. ANIONIC COMPOUNDS
PublicationSurfactants (SAA) with negative charge of polar group are named as anionic compounds. They are main constituent of most products containing synthetic surfactants. The linear alkylbenzene sulfonates (LAS), alkyl ethoxysulfates (AES) and alkyl sulfates (AS) are typically applied from this class of compounds. Those surfactants are ingredients of household detergents and cleaners, laundry detergents, cosmetic. Moreover they can be...
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Reliability assessment of truss towers using Monte Carlo Method, PEM and RSM
PublicationThe paper discusses the reliability assessment of simple random truss structures using three different probabilistic methodologies: the Monte Carlo method, the Point Estimate Method and the Response Surface Method. A benchmark truss structure example is analyzed. A set of numerical calculations of critical load is performed and the results are taken as the basis of advanced probabilistic calculations. Using the samples, numerical...
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ANALYSIS OF DIESEL OIL SPECIFIC HEAT IMPACT FOR OPERATION OF THE SUPPLY PUMP
PublicationThe article describes a test rig that allows the measurement of fuel oil specific heat changes based on the cooling time of liquids. After that, by analysing the test results, a research hypothesis was created and verified. The hypothesis is that the specific heat energy of fuel oil impact the operation of the circulation pump.
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A novel hybrid adaptive framework for support vector machine-based reliability analysis: A comparative study
PublicationThis study presents an innovative hybrid Adaptive Support Vector Machine - Monte Carlo Simulation (ASVM-MCS) framework for reliability analysis in complex engineering structures. These structures often involve highly nonlinear implicit functions, making traditional gradient-based first or second order reliability algorithms and Monte Carlo Simulation (MCS) time-consuming. The application of surrogate models has proven effective...
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Caveolin 2: a facultative marker of unfavourable prognosis in long-term patency rate of internal thoracic artery grafts used in coronary artery bypass grafting. Preliminary report
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Preexisting High Expression of Matrix Metalloproteinase-2 in Tunica Media of Saphenous Vein Conduits Is Associated with Unfavorable Long-Term Outcomes after Coronary Artery Bypass Grafting
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Importance of model tests in design and operation of watercraft for example CTO
PublicationShip Hydromechanics Division is a specialized research and development department of Ship Design and Research Centre conducting tests and research in the field of hydromechanics, connected with design and operation of ships and other floating structures, in scope of: predictions, numerical analyses, designs of - hull shape optimized with respect to the ship’s functions with the application of modern design tools, screw propellers...
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Application of BDD thin film electrode for electrochemical decomposition of heterogeneous aromatic compounds
PublicationThe aim of the presented study is to investigate the applicability of electrochemical oxidation of aromatic compounds containing heteroatoms, e.g. waste from production of pesticides or pharmaceutics, at a borondoped diamond (BDD) electrode. The BDD electrodes were synthesized by microwave plasma enhanced chemical vapour deposition (MW PE CVD). Investigation of the electrode surface by optical microscopy and scanning electron microscopy...
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Reliability assessment of truss towers using Monte Carlo Method, PEM and RSM
PublicationThe paper discusses reliability assessment of simple random truss structures using three different probabilistic methodologies: the Monte Carlo Method (MCM), the Point Estimate Method (PEM) and the Response Surface Method (RSM). A benchmark truss structure and a simplified full–size engineering tower are both analyzed. A set of ultimate load numerical calculations is performed and the results are taken as the basis of advanced...
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IDENTIFICATION OF ODOR OF VOLATILE ORGANIC COMPOUNDS USING CLASSICAL SENSORY ANALYSIS AND ELECTRONIC NOSE TECHNIQUE
PublicationThe paper compares two methods of analysis of odour of volatile organic compounds: classical sensory analysis and electronic nose technique. Eight volunteers participated in the classical sensory analysis investigations, which lasted two weeks. An instrumental odour analysis involved a prototype of 6-sensor electronic nose designed by the authors. The research performed with this device provided higher reproducibility and reliability...
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Influence of the particle size of carbonate-siliceous rock on the efficiency of phosphorous removal from domestic wastewater
PublicationtThe aim of the study was to determine the influence of the particle size of carbonate–silica rock (opoka)used in rock filters on the efficiency of phosphorus removal from domestic wastewater. The investigationswere carried out in a laboratory using a model consisting of three vertical flow filters with carbonate–silicarock of different particle sizes (G1= 1–2 mm; G2= 2–5 mm; G3= 5–10 mm). The tested rock was subjectedto decarbonising...
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Evaluation of Green Sample Preparation Techniques for Organic Compounds
PublicationNowadays, Green Analytical Chemistry (GAC) idea is of high importance, with impact on the rapid growth in the sample preparation area with special emphasis on sample preparation simplification, miniaturization and automation. Due to the fact that GAC is of high importance today, this study is focused on the evaluation of green sample preparation techniques for organic compounds. It is well known that sample preparation is considered...
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Numerical analysis of the flow rig for UWS spray examination in exhaust system-relevant conditions
PublicationIn the present study, a flow rig with optical access intended for spray investigations in exhaust system-relevant conditions was analysed in terms of flow and temperature in the spray area using numerical simulations. The operation of the rig was examined for a wide range of exhaust mass flow rates, temperatures and various forms of UWS (urea-water solution) spray plumes. The locations of the injector and thermocouple were verified....
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First evaluation of wastewater discharge influence on marine water contamination in the vicinity of Arctowski Station (Maritime Antarctica)
PublicationIn Antarctica,waste is generatedmainly during scientific research programmes and related logistics. In this study, the impact ofwastewater on the western shore of Admiralty Baywas investigated during austral summer in 2017 and 2019. A range of physicochemical parameters and the presence of selected trace metals, formaldehyde and different groups of surfactants were determined in wastewater coming from Arctowski Station and in nearby coastal...
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Sesonal changes of contamination removal in constructed wetlands system.
PublicationBadania prowadzona w dwch oczyszczalniach hydrofitowych zasilanych ściakami bytowo-gospodarczymi.Analizowany okres pomiarowy podzielono na sezon wegetacyjny (od kwietnia do października) oraz poza wegetacyjny (pozostałe miesiące).Uzyskane rezutlaty pozwoliły na oceną skuteczności usuwania zanieczyszczeń oraz wyznaczenie szybkości usuawania zanieczyszczeń w obu analizowanych okresach.
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Influence of oxygenation of constructed wetlands for effectiveness of contaminants removal
PublicationBadania prowadzono w trzech hybrydowych systemach hydrofitowych (HSH): Wiklinie, Wieszynie i Wiedersbergu. Obiekty charakteryzowały się różnym ładunkiem doprowadzanej SO. Określenie jakości SO w ściekach polegało na przeprowadzeniu analizy specjacji substancji organicznej zgodnie z metodyką podaną w niemieckich wytycznych ATV-131. Na podstawie analizy frakcji ChZT wykazano, że szybkość rozkładu SO (k) w złożach była determinowana...
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Fate and significance of phthalates and bisphenol A in liquid by-products generated during municipal solid waste mechanical-biological pre-treatment and disposal
PublicationSamples of liquid by-products generated by municipal solid waste plants (MSWPs) were tested for the presence of phthalates (PAEs) and bisphenol A (BPA). The results indicated that the wastewater generated during mechanical (sorting unit - SU) and biological (composting unit - CU) pre-treatment (MBT) of residual (mixed) solid waste is a significant source of these compounds. The concentrations of PAEs (up to 32222 lg/L) and BPA...
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Operational problems of large power diesel engines combusting biofuels, considered togetherwith assessment of their operation
PublicationWithin this article the issue of large power self ignition engines fed with biofuels has been undertaken. The analysis focused mainly on operation problems. There has been noticed some advantages and difficulties associated with the biofuel application to self ignition engines. The research problem has been characterised and the research purposes have been proposed enabling the most profitable formation of energetic features of...
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Comprehensive stabilization of all streams of solid residues formed during sewage sludge thermal treatment – Case study
PublicationModern wastewater treatment plants are currently struggling with the problem of processing and ecological management of sewage sludge. Thermal utilization is a frequently used practice of excess sludge utilization especially in large wastewater treatment plants, which seems to be a quite promising concept. However, during thermal treatment, fractions of ashes and dusts are generated. Such wastes, especially the dust fraction, can...
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Determinants of franchising operation development
PublicationRozdział w monografii opisujący uwarunkowania decydujące o rozwoju działalności franchisingowej na terenie danego kraju. Analiza prowadzona jest w odniesieniu do ogólnej sytuacji gospodarczej, sytuacji na rynku pracy, problematyki prawnej, promocji i edukacji franchisingowej oraz indywidualizmu ekonomicznego.
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Recent breakthroughs in the stability testing of pharmaceutical compounds
PublicationPharmaceutical development is mostly focused on the research leading to approval of a new and viable active substance. However, there is a number of old generation compounds that are still being used in contemporary medicinal practice. So that new analytical developments should cover not only the safety of newly developed drug substances, which is obvious, but should also be directed into the search of individual stability issues...