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The presence of pharmaceuticals or their active metabolites in receiving waters is a sign of the inefficient removal of bioactive substrates from wastewater. Adsorption seems to be the most effective and inexpensive method of their removal. Waste management aimed at sorbents is a promising way to sustain several sustainable development goals. In the presented paper, the removal of the two most widely used drugs in the wastewater was examined. Diclofenac and carbamazepine were removed from water and wastewater using textile waste-derived sorbents. Their removal efficiency was verified by testing several process parameters such as the time of the sorption, the presence of interfering inorganic ions, the presence of dissolved organic matter, the initial pH and ionic strength of the solution, and various water matrices. The adsorption capacity was noted for diclofenac (57.1 mg/g) and carbamazepine (21.25 mg/g). The tested process parameters (pH, presence of inorganic ions, dissolved organic matter, ionic strength, water matrix) confirmed that the presented waste materials possessed a great potential for pharmaceutical removal from water matrices. [ABSTRACT FROM AUTHOR]

The techniques used to detect and quantify cyanocobalamin (vitamin B12) vary considerably in terms of detection sensitivity, from the most sensitive, based on radioisotopes and mass spectrometry (MS) with limits of detection (LOD) in fg mL−1, to fluorescence (FL) and surface plasmon resonance (SPR) biosensors with LOD values in the range of a few µg mL−1. For accurate quantification of an analyte present at trace levels in complex biological matrices, a selective separation and enrichment step is required to overcome matrix interferences and ensure sufficient detection sensitivity. In this study, iron oxide magnetic nanoparticles (IONPs) were used for the extraction and initial preconcentration of cyanocobalamin (vitamin B12). In the dependence of the magnetization on the H-field (hysteresis loop), no coercivity and remanence values were found at 300 K, indicating the superparamagnetic properties of the tested IONPs. Perfluorinated acids were used as amphiphilic agents to allow the sorption of cyanocobalamin onto the IONPs. FT-IR/ATR spectroscopy was used to confirm the sorption of cyanocobalamin on the IONPs. The influence of the addition of a homologous series of perfluorinated acids such as trifluoroacetic acid (TFAA), heptafluorobutyric acid (HFBA), and trichloroacetic acid (TCAA) to the extraction mixture was tested considering their type, mass, and time required for effective sorption. The adsorption kinetics and isotherm, described by the Freundlich and Langmuir equations, were analyzed. The maximum adsorption capacity (qm) exceeded 6 mg g−1 and was 8.9 mg g−1 and 7.7 mg g−1 for HFBA and TCAA, respectively, as the most efficient additives. After the desorption process using aqueous KH2PO4 solution, the sample was finally analyzed spectrophotometrically and chromatographically. The IONP-based method was successfully applied for the isolation of cyanocobalamin from human urine samples. The results showed that the developed approach is simple, cheap, accurate, and efficient for the determination of traces of cyanocobalamin in biological matrices. [ABSTRACT FROM AUTHOR]

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents a rage of variable machining factors which influence substantially friction directly or by the abrasive media wear developed in the cutting zone. Abrasive flow machining is method of machining surfaces of complex holes and curved surface. In the case of traditional stream treatment methods abrasive (AFM) it is difficult to obtain a uniform roughness radial decomposition during polishing complicated openings, which results from uneven distribution of abrasive forces. The group of direct factors include the work piece materials and abrasive media, changes in the fluid pressure, number of flow cycles, the medium flow frequency. In addition, it was proposed modifications in the amount and size of grains abrasives filling the abrasive medium to increase the value of the grain pressure force on the surface to be processed and obtained an even surface of complex holes in the process AFM processing. Special attention was paid to the abrasive media wear evolution and its pronounced effect on changes of the contact conditions. The experiment results also confirm that the rise in the medium flow frequency during the process will not affect the roughness changes work piece surface.

This paper contains a description of tests including the simulation of the injection moulding of thin-walled products. The simulation was designed to analyse the potential impact of processing conditions and cooling conditions on the defects of thin-walled products of the body of the syringe. In order to obtain the correct results, the analysis was based on a simulation comparison with the data obtained after the injection mouldings were produced. Four cases were considered - parameters with reduced injection pressure and absence of pressure push, with a reduced temperature of the injection mould. The test results were analysed in conditions compliant with the recommendations of the production card and with the parameters optimised by computational algorithms of the computer programme. Simulations were carried out using the Simcon CadMould 3D-F programme. The paper describes the construction of a thin-walled body, which is the main segment of a medical instrument - a medical syringe. Also described in the paper are the process of injection of polymer materials and the characteristics of the production of medical syringes. In addition the computer programme software for the simulation of production processes was presented.

The article presents the results of the investigation of a rotor assembly of a wind turbine with a horizontal axis of rotation. The rotor is equipped with a diffuser which is an integral part of the power generating unit. The research was carried out by means of the ANSYS Fluent software. The geometry used for the tests is a development version of the construction shown in patent application PL 412553 and is characterised by an adjustable angle setting of the rotor blades. The geometric model was obtained by 3D scanning of the actual rotor using the ZScaner scanner ®700. The calculations were carried out for the selected blade angle of attack from 0° to 90° separately for the version with and without the diffuser. The results from the conducted tests were used to determine the characteristics of the power generated by the turbine as a function of rotor speed. The secondary objective of the tests was to analyse the effect of the diffuser on the power generated by the entire rotor assembly.

Complex composite materials are used in many areas of dentistry. Initially, chemically hardened materials were also used, and in this group nanohybrid composites are highly valued. They are often used today, mainly for the direct reconstruction of damaged hard tooth tissue materials for rebuilding damaged tissues using indirect adhesive techniques. The research was conducted to determine the mechanical properties of materials with nanofillers. The article focuses on methods of important test methods for dental prosthetics: resilience, abrasion, wear test, impact strength, hardness, SEM, and chemical analysis. As part of this work, five different series of hybrid composites with nano-fillers were tested. The mechanical properties of composites, such as compressive strength, microhardness, flexural strength, and modulus of elasticity, depend mainly on the type, particle size, and amount of filler introduced. The obtained test results showed that the type and amount of nanofiller have a significant influence on the mechanical and tribological properties. The introduction of nanofillers allowed us to obtain higher mechanical properties compared to classic materials discussed by other researchers. The study observed a change in vibrations in the IR spectrum, which allowed a comparison of the organic structures of the studied preparations. [ABSTRACT FROM AUTHOR]

The research was intended to develop a biocomposite as an alternative biodegradable material, for the production of, e.g., disposable utensils. The author’s tested thermoplastic maize starch, both without additives and with the addition of crumbled flax fiber in the share of 10, 20 and 30 wt%. The plasticizer added was technical glycerin and the samples were produced by a single-screw extruder. The mechanical strength tests were performed, including the impact tensile test and three-point bending flexural test. Afterwards, the samples were tested for biodegradability under anaerobic conditions. The methane fermentation process was carried in a laboratory bioreactor under thermophilic conditions with constant mixing of the batch. All samples proved to be highly susceptible to biodegradation during the experiment, regardless of the flax fiber share. The biogas potential was about 600 ml·g-1, and the methane concentration in biogas ranged from 66.8 to 69.6%. It was found, that the biocomposites can be almost completely utilized in bioreactors during the biodegradation process. The energy recovery in the decomposition process with the generation of significant amount of methane constitutes an additional benefit. [ABSTRACT FROM AUTHOR]

This study presents research concerning the development of an organosilicon polymer medium (polymethylhydroborosiloxane), that allows for the optimal selection of viscosity in the medium, for use as an admixture abrasive paste for abrasive flow machining. Based on the results of actual dynamic viscosity medium measurements, the influence of changes in temperature (25 °C, 50 °C and 75 °C) and in the concentration of the crosslinking solution (anhydrite boric acid - 2 wt.%, 4 wt.% and 6 wt.%) were studied. A number of crosslinking medium experiments were carried out, in which the characteristics of storage modulus G' and loss modulus G" of the medium containing different concentrations of crosslinking solutions at different temperature were determined. Due to the results obtained, it was possible to select the parameters of the crosslinking solution optimally both in terms of the temperature (50 °C) as well as its concentration (4 wt.%). [ABSTRACT FROM AUTHOR]

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)