Polymeric Complexes from Casein and Starch Phosphate: Characteristics and Enzyme Susceptibility

Novel biodegradable materials were prepared from potato starch enriched in phosphato moieties (DS 0.018 and 0.033) and casein in defatted milk. The components were blended in proportions providing starch: casein ratios of 2:1, 1:1, and 1:2 and were then precipitated with hydrochloric acid. Aqueous solubility, water-binding capacity, infrared spectra, and thermal analysis (thermogravimetry[7] and differential thermogravimetry of the precipitates revealed that they were not simple physical mixtures of the components. The components interacted with one another electrostatically with involvement of the phosphate groups of starch and the peptide bond of casein, as documented by infrared spectra. Because of insolubility in 7 M aqueous urea solution, they might also be considered as complexes in which the components were chemically bound.     

Radon concentrations in groundwaters of the Polish part of the Sudety Mountains (SW Poland)

In the course of researches into radon occurrence in the groundwaters of the Polish part of the Sudety Mountains, conducted in various research centres in Poland, almost 1000 radon concentration determinations have been collected. These results have given the basis for an attempt to characterise the groundwaters of this region with respect to radon content. Radon concentrations oscillated within the range of 0.2-1645 Bq/dm3, with the arithmetic mean at 240.0 Bq/dm3 and the geometric mean at 106.7 Bq/dm3. The largest number of radon concentrations found in the Sudetic groundwaters ranged between ca. 3-6 and 1000 Bq/dm3. The values over 1000 Bq/dm3 can be considered anomalously high. They constitute 3.9% of all the results and occur around six localities within different geological units of the Sudety Mountains. These are shallow circulation, low mineralised groundwaters, which outflow from gneisses and granites. In the face of the fact that from 12.8% to 72.7% (depending on the adopted norm of maximum radon concentration for drinking waters) of the examined waters cannot be drunk directly without removing at least part of the radon, and in the face of the possibility of recognizing as many as 63.5% of the waters as potentially medicinal, extensive research of radon geochemistry in the Sudety Mountains area should be urgently undertaken.     

Ammonium removal from waste solutions by precipitation of MgNH4PO4 I. Ammonium removal with use of commercial reagents

The method of ammonium ion removal from industrial waste solutions was investigated and parameters for MgNH₄PO₄ precipitation were determined. A solution laden with NH₄⁺ ions was brought to pH 1–2 by the use of H₃PO₄; MgO was then added and the pH adjusted to 9–10 with the use of NaOH solution. Stirring of the suspension was carried out during a prolonged period of time ( 3 hours), with final filtration or sedimentation. By this method the ammonium ion content in the filtrate may be reduced to concentrations below 1 mg/l. The MgNH₄PO₄·6H₂O sediment produced is considered to be a long-term fertilizer, suitable for agricultural use.     

Relationship between volatile organohalogen compounds in drinking water and human urine in Poland

Selected volatile organohalogen compounds (VOX) were investigated in urine samples from people living in different areas of the Gdańsk-Sopot-Gdynia TriCity (Poland). The analytes were isolated and preconcentrated using the so-called thin layer headspace technique with autogenous generation of the liquid sorbent. Final gas chromatographic determination was carried out by direct aqueous injection with electron capture detection. Analyte concentrations in drinking water ranged from not detected to approximately 8 microg/l (chloroform), depending on the source of drinking water in a given part of the TriCity (underground, surface or mixed). The corresponding urine levels were typically lower by about an order of magnitude. VOX levels in urine of people living in the parts of the TriCity supplied with drinking water containing elevated levels of the analytes were higher than the levels in urine of people whose drinking water originated from deep underground wells. The linear correlation coefficients for the relationships between total VOX and chloroform levels in drinking water and in urine were r2=0.65 and 0.88, respectively. The fraction of VOX excreted with urine in unchanged form did not exceed 20%.     

Extensions to minimum relative entropy inversion for noisy data

Minimum relative entropy (MRE) and Tikhonov regularization (TR) were compared by Neupauer et al. [Water Resour. Res. 36 (2000) 2469] on the basis of an example plume source reconstruction problem originally proposed by Skaggs and Kabala [Water Resour. Res. 30 (1994) 71] and a boxcar-like function. Although Neupauer et al. [Water Resour. Res. 36 (2000) 2469] were careful in their conclusions to note the basis of these comparisons, we show that TR does not perform well on problems in which delta-like sources are convolved with diffuse-groundwater contamination response functions, particularly in the presence of noise. We also show that it is relatively easy to estimate an appropriate value for epsilon, the hyperparameter needed in the minimum relative entropy solution for the inverse problem in the presence of noise. This can be estimated in a variety of ways, including estimation from the data themselves, analysis of data residuals, and a rigorous approach using the real cepstrum and the Akaike Information Criterion (AIC). Regardless of the approach chosen, for the sample problem reported herein, excellent resolution of multiple delta-like spikes is produced from MRE from noisy, diffuse data. The usefulness of MRE for noisy inverse problems has been demonstrated.     

Uptake of cadmium by Stichococcus bacillaris

The uptake of cadmium by the green alga $\text{Stichococcus bacillaris}$ was studied. It was found that about 80% of the uptake was due to adsorption, and about 20% to energy-dependent transport. Investigations on the relationship between the sorption of cadmium and the equilibrium concentration (Ce) revealed that the alga cells are saturated at Ce20mg Cd/1.     

Impact assessment of climate policy on Poland's power sector

This article addresses the impact of the European Union Emissions Trading System (EU ETS) on Poland’s conventional energy sector in 2008–2020 and further till 2050. Poland is a country with over 80% dependence on coal in the power sector being under political pressure of the European Union’s (EU) ambitious climate policy. The impact of the increase of the European Emission Allowance (EUA) price on fossil fuel power sector has been modelled for different scenarios. The innovation of this article consists in proposing a methodology of estimation actual costs and benefits of power stations in a country with a heavily coal-dependent power sector in the process of transition to a low-carbon economy. Strong political and economic interdependence of coal and power sector has been demonstrated as well as the impact caused by the EU ETS participation in different technology groups of power plants. It has been shown that gas-fuelled combined heat and power units are less vulnerable to the EU ETS-related costs, whereas the hard coal-fired plants may lose their profitability soon after 2020. Lignite power plants, despite their high emissivity, may longer remain in operation owing to low operational costs. Additionally, the results of long-term, up to 2050, modelling of Poland’s energy sector supported an unavoidable need of deep decarbonisation of the power sector to meet the post-Paris climate objectives. It has been concluded that investing in coal-based power capacity may lead to a carbon lock-in of the power sector. Finally, the overall costs of such a transformation have been discussed and confronted with the financial support offered by the EU. The whole consideration has been made in a wide context of changes ongoing globally in energy markets and compared with some other countries seeking transformation paths from coal. Poland’s case can serve as a lesson for all countries trying to reduce coal dependence in power generation. Reforms in the energy sector shall from the very beginning be an essential part of a sustainable transition of the whole nation’s economy. They must scale the power capacity to the future demand avoiding stranded costs. The reforms must be wide-ranging, based on a wide political consensus and not biased against the coal sector. Future energy mix and corresponding technologies shall be carefully designed, matched and should remain stable in the long-term perspective. Coal-based power capacity being near the end of its lifetime provides an economically viable option to commence a fuel switch and the following technology replacement. Real benefits and costs of the energy transition shall be fairly allocated to all stakeholders and communicated to the society. The social costs and implications in coal-dependent regions may be high, especially in the short-term perspective, but then the transformation will bring profits to the whole society.