Assemblages of molluscs have been used for stratigraphy of Late Glacial and Holocene deposits in Poland. Changes of the climate as well as migration of species are main factors which control the recompositions of molluscan communities in this time. Thirteen malacostratigraphical zones have been definied. Eight of them corresponds with land environments, while the remaining ones (five) with water habitats. The succesions of these zones gives the malacostratigraphical subdivisions, which can be compared with similar schemes proposed in some other countries of Central Europe. They supplement palynostratigraphical zones or even can be used as main way of stratigraphical intrepretations.
One of the consequences of the dynamic technological development is the rapidly increasing amount of electro-waste (WEEE, e-waste). Because there are no uniform legal regulations regarding the ways of collecting such waste, the separate-collection systems used in various areas are not homogeneous, and they usually also differ in effectiveness. The aim of this study was to evaluate the electro-waste collection system implemented in Lublin (the largest city in Eastern Poland). Taking into account the fact that the reliability of a collection system depends on the degree of its adaptation to the functions it performs, the evaluation consisted in determining how big a problem improper electro-waste segregation was. The article presents the results of a study of the causes of citizens’ failure to properly manage e-waste and indicates what measures should be taken to amend the problem. During two research steps, 347 pieces of e-waste with a total weight of 77.218 kg were found in the analyzed waste samples (0.33% of all samples). This means that the mechanisms of selective e-waste collection still do not work correctly, despite the ten years of Poland’s membership in the EU and implementation of European legislation in this area. The fact that residents throw away electric waste into municipal mixed waste containers poses a serious problem for proper waste management – even if only a part of the e-waste is disposed in this illegal way. This indicates the necessity of improving waste collection (more frequent waste reception, convenient access to e-waste containers, raising public awareness, etc.).
Nanoparticles are very fascinating area of science not only due to their unique properties but also possibility of producing new more complex materials, which may find an application in modern chemistry, engineering and medicine. In process of nanoparticles formation very important aspect is a rate of individual stage i.e. reduction, nucleation and autocatalytic growth, because this knowledge allows for proper materials design, morphology manipulation, stability. The last one aspect can be realized using proper electrostatic, steric and electrosteric stabilization. However until now nobody reports and measures kinetic rates of all stages during process of particles formation in the presence of steric stabilizers. Thus, the main contribution of this paper is determination of individual rate constants for nanoparticles formation in the presence of steric stabilizers and their comparison to the system without stabilizer. For this purpose, an aqueous solution of Au(III) and Pt(IV) ions were mixed with steric stabilizers like PVA and PVP, and reduced using L-ascorbic acid as a mild and sodium borohydride as a strong reductant. As a results stable nanoparticles were formed and process of their formation was registered spectrophotometrically. From obtained kinetic curves the values of observed rate constants for reduction metal ions, slow nucleation and fast autocatalytic growth were determined using Watzky-Finke model. It was found that the addition of polymer affects the rate of the individual stages. The addition of steric stabilizers to gold ions reduced with L-ascorbic acid causes that the process of nucleation and autocatalytic growth slows down and the value of observed rate constants for nucleation changes from 3.79·10–3 (without polymer) to 7.15·10–5s–1 (with PVA) and for growth changes from 1.15·103 (without polymer) to 0.48·102s–1M–1 (with PVA). However, the rate of the reduction reaction of Au(III) ions is practically unchanged. In case of using strong reductant the addition of polymer effects on the shape of kinetic curve for reduction of Au(III) and it suggests that mechanism is changed. In case of Pt(IV) ions reduction with L-ascorbic acid, the process speeds up a little when PVA was added. Determined values of observed rate constants for nucleation and growth platinum nanoparticles decrease twice comparing to the system without polymer. The reduction of Pt(IV) ions with sodium borohydride accelerates when PVP was added and slows down when PVA was used. Moreover, the size of obtained colloidal gold and platinum was also analysed using DLS method. Obtained results (rate constants) may be useful in the process of nanomaterials synthesis, in particular in microflow.
The consciousness of a crisis of university inclines towards its reformation. In the thinking about its revival it is necessary to take into account the archetypical idea behind university, traditions to date, contemporary conditions and visions of the future. It is also getting indispensable to take into consideration such values that ought to steer the development of university in the framework of global civilization. The tasks of university are as follows: 1) to conduct research in striving for truth in the conditions of autonomy and freedom, as well as responsibility for the present day and the future of man; 2) to educate students, which introduces them in the world of science and life, as well as teaches them to be responsible; 3) to practice public science which is present in debates undertaking to solve vital social problems. The academic community and its elites should defend the conception of university against the dictate of their political and economic counterparts who attempt to impose the idea of an entrepreneurial university which produces a utilitarian knowledge and “human principles”.