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Wyniki wyszukiwania dla: BIODEGRADABLE METALLIC IMPLANT
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Conducting polymers for biodegradable metallic implants
PublikacjaNowadays permanent metallic cardiovascular stents are long-term implants. The long-time presence of such an implant in human body can cause overgrowth of tissue within the treated portion of the vessel, blockage of the circulatory system and many other clinical complications, such as thrombosis, prolonged physical irritations or chronic inflammation. Therefore, in recent years, there is an interest to create biodegradable metallic...
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Conducting polymer films for biodegradable metallic cardiovascular stents
PublikacjaIn recent years, there is increasing interest to create biodegradable metallic cardiovascular stents instead of using their permanent form. The most interesting materials for this purpose are iron and its alloys. However, in order to use it in clinical application, their degradation rate and biological performance need to be optimized. One promising solution is coating the metal with conducting polymer films. In this work, short...
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Electrophoretic deposition and characterization of composite chitosan/Eudragit E 100 or poly(4-vinylpyridine)/mesoporous bioactive glass nanoparticles coatings on pre-treated titanium for implant applications
PublikacjaTitanium implants are surface-modified to achieve bioactivity and often antibacterial properties. Such surface coatings may increase corrosion degradation and be weakly attached to the substrate. In the present research, biodegradable composite coatings, investigated so far as smart environment-sensitive, slowly releasing silver to the implant neighborhood, were produced as a combination of chitosan (CS) with Eudragit E 100 (EE100)...
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Formation of Porous Structure of the Metallic Materials Used on Bone Implants
PublikacjaResearch on improvement of structure and fabrication methods of the bone implants are carried out for many years. Research are aimed to shape the structures, that will have a Young's modulus value similar to the value of the human bones Young's modulus. Depending on theporosity, Young's moduli can even be tailored to match the modulus of bone closer than solid metals can, thus reducing the problems associated with stress shielding...
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Structural changes of bacterial cellulose due to incubation in conditions simulating human plasma in the presence of selected pathogens
PublikacjaBacterial nanocellulose (BNC) is a natural biomaterial with a wide range of medical applications. However, it cannot be used as a biological implant of the circulatory system without checking whether it is biodegradable under human plasma conditions. This work aimed to investigate the BNC biodegradation by selected pathogens under conditions simulating human plasma. The BNC was incubated in simulated biological fluids with or...
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Biocompatibility and bioactivity of load-bearing metallic implants
PublikacjaThe main objective of here presented research is to develop the titanium (Ti) alloy base composite materials possessing better biocompatibility, longer lifetime and bioactivity behaviour for load-bearing implants, e.g. hip joint and knee joint endoprosthesis. The development of such materials is performed through: modeling the material behaviour in biological environment in long time and developing of new procedures for such evaluation;...
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Investigations of Titanium Implants Covered with Hydroxyapatite Layer
PublikacjaTo reduce unfavorable phenomena occurring after introducing an implant into human body various modifications of the surface are suggested. Such modifications may have significant impact on biocompatibility of metallic materials. The titanium and it's alloys are commonly used for joint and dental implants due to their high endurance, low plasticity modulus, good corrosion resistance as well as biocompatibility. Special attention...
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Electrophoretic Deposition of Chitosan/Eudragit E 100/AgNPs Coatings for Controlled Release of Antibacterial Substance
PublikacjaThe development of bacterial infection of the tissues surrounding an implant is one of the leading causes of implant surgery failure. In order to prevent the deposition of bacteria on the implant surface and the formation of biofilm, coatings that exhibit antibacterial properties are manufactured. However, the problem is the controlled release of the therapeutic substance from the coating over the extended life of the implant [1],...
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Allergic reactions as a defense of the organism to the influence of implants components made of stainless steel
PublikacjaDue to the increasing number of cases of hypersensitivity caused by direct contact with metals, as well as the increasing demand for implants in humans all ages numerous studies on the effects of the impact of implant components are being carried out. The paper presents the phenomenon of etiology of allergy in general terms and in relation to the biomaterials used in medicine. There have been characterized in terms of impact on...
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Allergic Reactions as a Defense of the Organism to the Influence of Implants Components Made of Stainless Steel
PublikacjaDue to the increasing number of cases of hypersensitivity caused by direct contact with metals, as well as the increasing demand for implants in humans all ages numerous studies on the effects of the impact of implant components are being carried out. The paper presents the phenomenon of etiology of allergy in general terms and in relation to the biomaterials used in medicine. There have been characterized in terms of impact on...
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Influence of Surface Modification of Titanium and Its Alloys for Medical Implants on Their Corrosion Behavior
PublikacjaTitanium and its alloys are often used for long-term implants after their surface treatment. Such surface modification is usually performed to improve biological properties but seldom to increase corrosion resistance. This paper presents research results performed on such metallic materials modified by a variety of techniques: direct voltage anodic oxidation in the presence of fluorides, micro-arc oxidation (MAO), pulse laser treatment,...
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Bioactive core material for porous load-bearing implants
PublikacjaSo far state of knowledge on biodegradable materials is reviewed. Among a variety of investigated materials, those composed of polymers and ceramics may be considered as only candidates for a core material in porous titanium alloy. The collagen and chitosan among natural polymers, polyhydroxy acids among synthetic polymers, and hydroxyapatite and tricalcium phosphate among ceramics are proposed for further research. Three essential...
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The biological reactions on the implant-organism border
PublikacjaMateriał przeznaczony do implantacji w tkanki żywego organizmu powinien być biozgodny i biofunkcjonalny. Jeśli tak nie jest, ciało reaguje stanem zapalnym. Reakcje zapalne mogą się objawiać np. odrywaniem się cząstek materiału z powierzchni implantu na skutek tarcia lub nacisku, lub wytworzeniem biofilmu na jego powierzchni.
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Degradation of implantable materials – in vivo and in vitro research
PublikacjaThe article concerns the biological and electrochemical degradation of metallic implants in vivo and in vitro studies. The in vivo research dealt with degradation of plates used to join bones, as well as endoprostheses. The most common damages were: metalosis, breaking in the microstructure changes, breaking in area of holes, as well as plastic deformation throughout the length of an implant. The material used for the research...
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Surgical implant used in ventral hernia repair subjected to physiological pressure - computer simulation
PublikacjaW streszczeniu przedstawiono matemayczny model implantu wszczepionego pacjentowi podczas laparoskopowej naprawy przepukliny brzusznej. Wykonano go z użyciem metody elementów skończonych. Przyjęto ortotropowy model materiałowy implantu.
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Degradation of metallic implants
PublikacjaPresence of metallic implants made of stainless steels, Co and Ti alloys is sometimes followed by some undesired allergic reactions and inflammatory processes and consequently the necessity of reimplantation.
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Developing Materials for Biodegradable Otolaryngological Stents
PublikacjaMaterials for otolaryngological stents have to be characterized by good tensile strength, wear resistance, biocompatibility, and specific degradation time. This work aimed to synthesize polyurethanes based on various biodegradable polyol blends. Their biodegradability and mechanical properties were tested and compared to commercial BIOFLEX material.
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Biodegradable Polymer Packaging Materials in Seawater Environment
PublikacjaIn this chapter, our interest is directed into dea/ocean/lakes biodegradable environment for polymer packaging materials from two different points of view.
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Biodegradable polymer packaging materials - influence on environment
PublikacjaAwareness of the waste problem and its impact on the environment has awakened new interest in the area of biodegradable polymers. Biodegradation of various polymers have been studied under diverse environments like in soil, in sewage sludge, in compost conditions and in sea water by different research groups. The aim of this paper is to present the research methods on the biodegradation of the commercially available biodegradable...
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Allergy to implant components: chromium, nickiel, cobalt and titanium
PublikacjaImplant jest kompozycja roznych pierwiastkow: niklu, chromu, kobaltu, tytanu, molibdenu i wanadu. Pierwiastki te moga doprowadzic do alergii, egzemy i obluzowania implantu.
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Mathematical modelling of implant in an operated hernia for estimation of the repair persistence
PublikacjaThis paper presents mathematical modelling of an implanted surgical mesh used in the repair process of the abdominal hernia. The synthetic implant is simulated by a membrane structure. The author provides a material modelling of the implant based on the dense net model appropriate for technical fabrics. The accuracy of the proposed solution is evaluated by comparing the simulations of the dynamic behaviour of the system with the...
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Nanotubular Ti Oxide Layers for Enhancement of Bone-Implant Bonding and Bioactivity
PublikacjaAbstrakt artykułu pt. ''Nanotubular Ti Oxide Layers for Enhancement of Bone-Implant Bonding and Bioactivity''. The paper describes techniques to improve the bioactivity of titanium and ehnahnce the bone-implant bonding ability by the electrochemical anodization to fabricate titania nanotubular oxide layer.
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Tailoring the electrochemical degradation of iron protected with polypyrrole films for biodegradable cardiovascular stents
PublikacjaThe degradation of polypyrrole (PPy) coated iron is studied in phosphate buffer saline solution at 37 °C by odd random phase multisine electrochemical impedance spectroscopy (ORP-EIS). PPy is electropolymerized with anti-inflammatory salicylates incorporated in the film, as a drug release system. The modelling of EIS over time provides the quantitative description of the corrosion behaviour of the material. Thus, the reliable...
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Zastosowanie próby implant do oceny spawalności stali
PublikacjaPraca dotyczy oceny spawalności stali o podwyższonej i wysokiej wytrzymałości w aspekcie eksperymentalnego określania skłonności do tworzenia pęknięć zimnych. W artykule opisano metodykę określania wrażliwości na pękanie próbą implant. Przedstawiono również proponowane w literaturze i autorskie sposoby opracowywania i przedstawiania wyników badań rozpatrywaną metodą i ich interpretacji.
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Trudności podczas modelowania próby implant w programie Ansys.
PublikacjaW artykule przedstawiono trudności związane ze stworzeniem modelu próby implant w programie Ansys. Określono również trudności związane z przypisaniem odpowiednim strefom połączenia spawanego własności mechanicznych.
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IMPLANT USED IN HERNIA REPAIR UNDER PHYSIOLOGICAL MOVEMENTS OF HUMAN ABDOMEN
PublikacjaThe study deals with the mechanical behaviour of implant used in repair of abdominal hernia. The influence of orientation of the orthotropic implants in different areas of abdominal wall is studied.
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Nanotubular Titanium Oxide Layers for Enhancement of Bone-Implant Bonding and Bioactivity
PublikacjaThe present paper describes the techniques to improve the bioactivity of titanium and enhance the bone-implant bonding ability by the electrochemical anodization to fabricate titania nanotube arrays (TiO2).
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A PRELIMINARY STUDY ON THE OPTIMAL CHOICE OF AN IMPLANT AND ITS ORIENTATION IN VENTRAL HERNIA REPAIR
PublikacjaThis paper addresses the problem of ventral hernia repair. The main goals are to find an optimal surgical mesh for hernia repair and to define its optimal orientation in the abdominal wall to minimise the maximum force at the tissue-implant juncture. The optimal mesh is chosen from a set of orthotropic meshes with different stiffness ratios for typical hernia placement in the abdominal area. The implant is subjected to an anisotropic...
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Orthotropic membrane as a mechanical model of surgical implant in abdominal hernia repair
PublikacjaEven though the incisional hernia repair surgery is a well known procedure, mechanical properties of the tissue-implant system are unknown so the implantation of the repairing mesh is quite intuitive and, recurrences of the illness still take place. The main objective of the study is to define an operated hernia model that can be used for surgery planning and the assessment of the repair persistence. The load applied to the structure...
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The Hydrolysis of Slowly Biodegradable Substrate in Activated Sludge
PublikacjaIn a present work a novel procedure, based on the standard batch tests and pretreatment of wastewater sample with coagulation-flocculation method, was proposed to evaluate the effects of hydrolysis of slowly biodegradable substrate (Xs) on biological nutrient removal (BNR) processes in activated sludge systems. The study was conducted at two large BNR wastewater treatment plants (WWTPs) in northern Poland: "Wschod" in Gdansk and...
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Behaviour of orthotropic surgical implant in hernia repair due to the material orientation and abdomen surface deformation
Publikacjarelation to the different range of typical deformations observed in different directions and zones of abdomen surface due to the patients’ life activities, has a significant influence on the extreme junction forces in the mesh–tissue connections and hence the repair persistence. The finite element model of the orthotropic implant was developed, and the junction forces in the connections of tissue and mesh were studied. The kinematical...
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Mathematical study of a tissue-implant connection in a ventral herniarepair in a context of the system's parameters
PublikacjaW pracy przedstawiono problem operowania przepuklin brzusznych u ludzi. Zaproponowano jednowymiarowy model układu powieź-implant. Na podstawie analizy wrażliwości zidentyfikowano najważniejsze parametry problemu.
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Biodegradable polymers for food packaging - factors influencing their degradation and certification types - a comprehensive review
PublikacjaIn the paper an overview of novel biodegradable polymers for food packaging can be found. The aim was to present factors influencing polymer degradation and biodegradation in various environments. It was noted that biodegradable polymers are imperfect alternative for classical polymers and its decomposition strongly depends on degradation environment.
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Biocompatibility and Bioactivity of Load-Bearing Metallic Implants
PublikacjaThe main objective of here presented research is to develop the titanium (Ti) alloy base composite materials possessing better biocompatibility, longer lifetime and bioactivity behaviour for load-bearing implants, e.g. hip joint and knee joint endoprosthesis. The development of such materials is performed through: modeling the material behaviour in biological environment in long time and developing of new procedures for such evaluation;...
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Reactive extrusion of biodegradable aliphatic polyesters in the presence of free-radical-initiators: A review
PublikacjaNowadays, growing attention is being paid to the environment and sustainability, what fully justified research works focused on modification of biodegradable polymers and their composites. In this field of research reactive extrusion seems to be the most promising approach, which fits well to sustainable development strategy. In In the present work, the in-situ modification of biodegradable aliphatic polyesters and the compatibilization...
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Mechanical behaviour of the implant used in human hernia repair under physiological loads
PublikacjaIn laparoscopic operations of abdominal hernias some recurrences still take place, even when applying a surgical mesh. This is usually caused by a failure of the connection between the tissue and the implant. The study deals with the influence of an implant’s orientation on forces in joints, which connect the mesh to human tissues. In the paper, the implant is modelled as a membrane structure within framework of the Finite Element...
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The impact of slowly biodegradable organic compounds on the oxygen uptake rate in activated sludge systems
PublikacjaThe hydrolysis process of slowly biodegradable substrate (Xs) have impact on the efficiencies of nutrient removal in activated sludge systems. Measurement of OUR and corresponding COD is accepted as a very useful tool to reflect the consumption of biodegradable substrates. The influence of the readily biodegradable substrate (Ss) in biological wastewater treatment systems has been extensively investigated, but little is known about...
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The impact of slowly biodegradable organic compounds on the oxygen uptake rate in activated sludge systems
PublikacjaThe hydrolysis process of slowly biodegradable substrate (Xs) have impact on the efficiencies of nutrient removal in activated sludge systems. Measurement of OUR and corresponding COD is accepted as a very useful tool to reflect the consumption of biodegradable substrates. The influence of the readily biodegradable substrate (Ss) in biological wastewater treatment systems has been extensively investigated, but little is known about...
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Low-Profile Interdigitated UHF RFID Tag Antenna for Metallic Objects
PublikacjaThis article presents a novel miniature interdigitated ultra-high frequency (UHF) radio frequency identification (RFID) tag antenna that can be placed on metallic objects. The tag structure comprises two horizontal strip lines, each loaded with seven identical open stubs, and an integrated circuit (IC) chip connected directly to the feed lines in the middle of the structure. The perfect match to the IC chip’s impedance is realized...
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Physical and mathematical modelling of implant-fascia system in order to improve laparoscopic repair of ventral hernia
PublikacjaThis paper describes an investigation of biomechanical behaviour of hernia repair, which is focused on the selection of safe linking of certain type of implant with fascia in laparoscopic operation. The strength of various fixations of the implant to the fascia is analysed. Methods: The research is based on experimental observations of operated hernia model behaviour during a dynamic impulse load corresponding to post-operative...
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Dynamics of mechanical model of implant-tissue system in ventral hernia repair
PublikacjaThe paper deals with a finite element modelling of implants in the problem of ventral hernia repair. The synthetic mesh implanted in the abdomen during surgery is here modelled as a membrane structure. Thesystem undergoes the internal abdominal pressure that occurs during the postoperative cough, the load identified in the literature as the main cause of the connection failure and hernia recurrence. The model can be used to estimate...
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A FEM membrane model of human fascia-synthetic implant system in a case of a stiff ventral hernia orifice
PublikacjaPraca prezdstawia model matematyczny układu tkanka ludzka - implant syntetyczny w postaci tzw. siatki w leczeniu przepuklin brzusznych. Implant jest tu moelowany jako struktura membranowa. Ocena wpływu danych materiałowych oraz wstępnego napięcia na zachowanie pracującej membrany po implantacji została przedstawiona na podstawie analizy wrażliwości. Pracę podsumowują pewne wskazówki dla chirurgów implantujących siatki.
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Investigation on Filaments for 3D Printing of Nasal Septum Cartilage Implant
PublikacjaSeptoplasty is a widely used method in treating deviated septum. Although it is successfully implemented, there are problems with excessive bleeding, septal perforation, or infections. The use of anatomically shaped implants could help overcome these problems. This paper focuses on assessing the possibility of the usage of a nasal septum cartilage implant 3D printed from various market-available filaments. Five different types...
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Influence of the electrosynthesis conditions on the spontaneous release of anti-inflammatory salicylate during degradation of polypyrrole coated iron for biodegradable cardiovascular stent
PublikacjaIn this work, the spontaneous release of anti-inflammatory salicylate from polypyrrole (PPy) coated iron has been studied during degradation of the material in phosphate buffer saline at 37 C. The sodium salicylate was incorporated into PPy in a one-step electropolymerization process. The influence of the synthesis conditions such as sodium salicylate concentration, pyrrole concentration and deposition charge on drug release profile...
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Bandwidth Dependence of the Propagation Channel in Circular Metallic BAN Environments
PublikacjaIn this paper, the bandwidth dependence of the propagation channel for Body Area Networks (BANs) in circular metallic environments is addressed and models are proposed to evaluate the appropriate short-term fading margins that should be considered as a function of the system bandwidth. The deployment of BANs in metallic indoor environments, such as ships, factories, warehouses and other similar environments, involves additional...
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Fast Fading Characterization for Body Area Networks in Circular Metallic Indoor Environments
PublikacjaWith the increasing development of 5G and Body Area Network based systems being implemented in unusual environments, propagation inside metallic structures is a key aspect to characterize propagation effects inside ships and other similar environments, mostly composed of metallic walls. In this paper, indoor propagation inside circular metallic structures is addressed and fast fading statistical distributions parameters are obtained...
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Estimation and modeling hydrolysis of slowly biodegradable substrate based on the batch respirometric tests in activated sludge systems
PublikacjaNowadays, appropriate determination of chemical oxygen demand (COD) fractionation together with degradation kinetics of organic compounds have a prime importance on the design and operation of activated sludge systems. Batch respirometric tests based on the oxygen uptake rates (OUR) and corresponding COD is accepted method to reflect the consumption of biodegradable substrates. The influence of the readily biodegradable (Ss) fraction...
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Preparation and characterization of biodegradable and compostable PLA/TPS/ESO compositions
PublikacjaIn this study, biodegradable and compostable compositions, derived from totally natural feedstock/raw materials, namely polylactide (PLA), potato thermoplastic starch (TPS) and plant glycerin have been made by melt extrusion with epoxydized soybean oil (ESO) as reactive modifier in order to improve PLAs ductility and reduce the products cost without compromising biodegradation. The obtained PLA/mTPS(0,5ESO)[75/25] and PLA/ mTPS(2ESO)[75/25]...
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Comparison of experimental and numerical results on metallic plates subjected to explosions
PublikacjaA comparative study of dynamic response including damage and rupture processes of thin metallic plates subjected to shockwave impulses - explosions is presented. The results of the finite element numerical analysis are related to experiments. Due to high strain rate during explosions the elasto-viscoplastic Chaboches constitutive law including damage effects has been applied. For the assumed model proper material parameters identification...
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Modeling the Effects of Slowly Biodegradable Substrate at Large WWTP in Northern Poland
PublikacjaThe essential study was divided into two parts: experimental investigation and mathematical modeling using special platform to computer simulations. In the first part of research an innovative measurement procedure for an indirect determination of the effect of biodegradable particulate and colloidal Xs substrate was developed and implemented. The results of laboratory tests were used futher to verify the mechanism of the hydrolysis...