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71.
Summary Hardwood sawdust was derivatized either by carboxymethylation, glutaration, maleiation, phthallation, or succination in order to produce anionic materials suitable for complexation with soy protein isolate. Blending each derivative with soy protein isolate resulted in instant precipitation of gels. Infrared spectroscopy and differential scanning calorimetry suggested that each derivative formed a complex with protein. Reaction products could be dried into pellets exhibiting tensile strengths between 0.9–2.4 MPa, suggested that these materials could be promising candidates for biodegradable structural materials.  相似文献   
72.
73.
Introduction to the problem of environmental pollution caused by acid depositions. Presentation of principles of the six-year field experiment with simulated acid rain. Short characteristics of particular parts of the series of papers.  相似文献   
74.
The paper concerns a hydrometallurgical method for selective recovery of copper from low-grade electric and electronic wastes. The following consecutive stages were proposed: smelting of the scraps to produce Cu–Zn–Ag alloy, leaching of the alloy in ammoniacal solution, and selective copper electrowinning. Cu–Zn–Ag alloy was a polymetallic and five-phase system. It was leached in chloride, carbonate, sulfate and thiosulfate solutions. This resulted in the separation of the metals, wherein metallic tin and silver as well as lead salts remained in the slimes, while copper and zinc were transferred to the electrolyte. Copper was selectively recovered from the ammoniacal solutions by the electrolysis, leaving zinc ions in the electrolyte. The best conditions of the alloy treatment were obtained in the ammonia–carbonate system, where the final product was copper of high purity (99.9 %) at the current efficiency of 60 %. Thiosulfate solution was not applicable for the leaching of the copper alloy due to secondary reactions of the formation of copper(I) thiosulfate complexes and precipitation of copper(I) sulfide, both inhibiting dissolution of the metallic material.  相似文献   
75.
Located in a relatively dry region and characterized by mainly sandy soils, the German Federal State of Brandenburg (surrounding the capital city of Berlin) is especially vulnerable to climate change impacts (e.g., summer droughts) and cascading effects on ecological systems (e.g., decreasing ground water tables, water stress, fire risk, productivity losses) with socioeconomic implications. Furthermore, a complex interplay of unemployment, rural exodus, and an aging population challenges this structurally weak region. We discuss adaptation measures that are either implemented or planned, as well as research into adaptation strategies to climate change for the sectors forestry, agriculture, and water management as well as in nature conservation in light of socioeconomic and ecological challenges and benefits. In doing so, we adopt a systemic view of Brandenburg where the sectors discussed are seen as subsystems embedded in a larger regional system. This at least partially holarchical approach enables the identification of conflicts between adaptation measures, but also of synergies among the sectors that pertain to successful adaptation to climate change. The insights gained ultimately highlight the need for cross-sectoral, adaptive management practices that jointly target a sustainable regional development.  相似文献   
76.
Passive techniques are a constantly evolving approach to the long-term monitoring of micropollutants, including pharmaceuticals, in the aquatic environment. This paper presents, for the first time, the calibration results of a new CNTs-PSDs (carbon nanotubes used as a sorbent in passive sampling devices) with an examination of the effect of donor phase salinity, water pH and the concentration of dissolved humic acids (DHAs), using both ultrapure and environmental waters. Sampling rates (Rs) were determined for the developed kinetic samplers. It has been observed that the impact of the examined environmental factors on the Rs values strictly depends on the type of the analytes. In the case of β-blockers, the only environmental parameter affecting their uptake rate was the salinity of water. A certain relationship was noted, namely the higher the salt concentration in water, the lower the Rs values of β-blockers. In the case of sulfonamides, water salinity, water pH 7–9 and DHAs concentration decreased the uptake rate of these compounds by CNTs-PSDs. The determined Rs values differed in particular when the values obtained from the experiments carried out using ultrapure water and environmental waters were compared. The general conclusion is that the calibration of novel CNTs-PSDs should be carried out under physicochemical conditions of the aquatic phase that are similar to the environmental matrix.  相似文献   
77.
The content of arsenic (As) in mushrooms can vary depending on the concentration level of this metalloid in the soil/substrate. The present study evaluated the content of arsenic in Boletus badius fruiting bodies collected from polluted and non-polluted sites in relation to the content of this element in overgrown substrate. It was found that mushrooms from the arsenic-polluted sites contained mean concentrations from 49 to 450 mg As kg?1 dry matter (d.m.), with the greatest content found for specimens growing in close proximity of sludge deposits (490±20 mg As kg?1d.m.). The mean content of total arsenic in mushrooms from clean sites ranged from 0.03 to 0.37 mg kg?1 It was found that B. badius could tolerate arsenic in soil substrate at concentrations of up to 2500 mg kg?1, at least. In different years of investigation, shifts in particular arsenic forms, as well as a general increase in the accumulation of organic arsenic content, were observed. The results of this study clearly indicate that B. badius should not be collected for culinary purposes from any sites that may be affected by pollution.  相似文献   
78.
Investigations were carried out in the Department of Conservation of Painting and Polychrome Sculpture and in the Screen Printing Studio of the Faculty of Art at Nicolaus Copernicus University. Concentration of the vapours of organic solvents was measured in 2 workshops: the Art Conservation Studio and the Screen Printing Studio. This study attempts to evaluate the work environment in both studios by analysing the concentration of vapour solvents over 5 to 7 years of measurements. Volatile solvents--aliphatic and aromatic hydrocarbons, alcohols, esters and ketones--were detected in investigated workplaces. These compounds have a wide range of applications in cleaning and removing old varnishes, lacquers and paints; inhalation is the main route of exposure. Vapour was collected using an active sampling method.  相似文献   
79.
This paper shows the concept and preliminary test of the composting process control with fuzzy logic. The temperature in the compost heap during the process is greater than 80 °C. Because wastes of agricultural origin do not require hygienization, part of the heat can by retrieved, which lowers the temperature in the heap to 55 °C (this is also the optimum temperature for the composting process). The heat retrieved from a compost heap can be used in another place. Therefore, a composting system was developed in which the aeration rate and heat removal rate can be adjusted. There are two goals of this system: maximising the amount of the heat retrieved from the heap and minimising the duration of the composting process. In the preliminary experiments freshly mown grass with 50 % cabbage was used as the compost material. The results show that the fuzzy logic control system functions correctly with respect to calculations. During the study, a median 90 MJ of heat was produced by the bioreactor; the thermophilic phase was shortened to 12 days. There was also a reduction in the emission of ammonia.  相似文献   
80.
The aim of the study was to estimate copper (Cu) accumulation efficiency in whole-fruiting bodies of 18 edible and non-edible wild growing mushrooms collected from 27 places in the Wielkopolska Voivodeship. Mushrooms were collected each time from the same places to estimate the diversity in Cu accumulation between tested mushroom species within 3 consecutive years of study (2011–2013). The study results revealed various accumulation of Cu in the whole-tested mushroom fruiting bodies. The highest mean accumulation of Cu was observed in Macrolepiota procera (119.4 ± 20.0 mg kg?1 dm), while the lowest was in Suillus luteus and Russula fellea fruiting bodies (16.1 ± 3.0 and 18.8 ± 4.6 mg kg?1 dm, respectively). Significant differences in Cu accumulation between mushroom species collected in 2011 and in the two following years (2012 and 2013) were observed. The results indicated that sporadic consumption of these mushrooms was not related to excessive intake of Cu for the human body (no toxic influence on health).  相似文献   
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