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51.
Marcin Wysokowski ?ukasz Klapiszewski Dariusz Moszyński Przemys?aw Bartczak Tomasz Szatkowski Izabela Majchrzak Katarzyna Siwińska-Stefańska Vasilii V. Bazhenov Teofil Jesionowski 《Marine drugs》2014,12(4):2245-2268
Novel, functional materials based on chitin of marine origin and lignin were prepared. The synthesized materials were subjected to physicochemical, dispersive-morphological and electrokinetic analysis. The results confirm the effectiveness of the proposed method of synthesis of functional chitin/lignin materials. Mechanism of chitin modification by lignin is based on formation of hydrogen bonds between chitin and lignin. Additionally, the chitin/lignin materials were studied from the perspective of waste water treatment. The synthetic method presented in this work shows an attractive and facile route for producing low-cost chitin/lignin biosorbents with high efficiency of nickel and cadmium adsorption (88.0% and 98.4%, respectively). The discovery of this facile method of synthesis of functional chitin/lignin materials will also have a significant impact on the problematic issue of the utilization of chitinous waste from the seafood industry, as well as lignin by-products from the pulp and paper industry. 相似文献
52.
Masternak Katarzyna Oko Sylwia Kamola Marek Ociepa Tomasz Nucia Aleksandra Kowalczyk Krzysztof 《European Journal of Forest Research》2022,141(4):617-628
European Journal of Forest Research - Increasing areas of gradation, making it difficult or impossible to perform restorations and forestations, and as causing tree crown damage, result in the need... 相似文献
53.
Foss Kamil Przybyłowicz Katarzyna E. Sawicki Tomasz 《Plant foods for human nutrition (Dordrecht, Netherlands)》2022,77(3):383-389
Plant Foods for Human Nutrition - Herbs are characterized by a high content of biologically active substances that positively affect human health. Phenolic compounds are one of the main bioactive... 相似文献
54.
Aki Sinkkonen Sari Kauppi Veera Pukkila Hui Nan Tomasz Płociniczak Merja Kontro Rauni Strömmer Martin Romantschuk 《Journal of Soils and Sediments》2013,13(8):1430-1438
Purpose
Previous investigations—field samplings and laboratory experiments—support the hypothesis that the degradation of s-triazines is enhanced in previously exposed as compared to pristine soils in terrestrial environments. Despite this, bottlenecks of soil sampling and various soil modification practices in microcosm studies have made it difficult to guarantee that previous contamination history enhances contaminant degradation regardless of soil origin in terrestrial ecosystems. We test the hypothesis that the degradation of simazine (2-chloro-4,6-bis(ethylamino)-s-triazine) is enhanced in previously exposed soils as compared to pristine soils in 10 l buckets at the mesocosm scale.Materials and methods
We collected soil at three separate sites consisting of a previously exposed and a pristine field. At every field, soil was collected at three separate plots and simazine degradation (days 0 and 65) and the response to atzB degrader gene primers (days 0 and 110) were followed. We analyzed the results using analysis of covariance (ANCOVA). Previous exposure and field site were assessed as fixed factors and initial simazine concentration and abiotic soil conditions as covariates.Results and discussion
After the 65-day exposure, remaining simazine concentrations depended on previous exposure but not on collection site. The response to atzB gene primers was positive in all mesocosms where simazine degradation had been rapid. Soil moisture, pH, and organic matter content were insignificant. If soil moisture was not included in the ANCOVA model, previous exposure did not appear as a significant factor.Conclusions
The results support the hypothesis that simazine is degraded more rapidly in previously exposed soils as compared to pristine environments, provided that degradation genes are available. Previously exposed soil might be used to enhance the degradation of simazine in recently contaminated terrestrial soils, supposing that the central requirements for microbial growth are adequate. 相似文献55.
Kazimierz A. Orlowski Tomasz Ochrymiuk Anthony Atkins Daniel Chuchala 《Wood Science and Technology》2013,47(5):949-963
In the classical approach, energetic effects (cutting forces and cutting power) of wood sawing process are generally calculated on the basis of the specific cutting resistance, which is in the case of wood cutting the function of more or less important factors. On the other hand, cutting forces (or power—more interesting from energetic point of view) could be considered from a point of view of modern fracture mechanics. Cutting forces may be employed to determine not only toughness but also shear yield strength, which are then applied in the models. Furthermore, forecasting of the shear plane angle for the cutting models, which include fracture toughness in addition to plasticity and friction, broadens possibilities of energetic effects modelling of the sawing process even for small values of the uncut chip. Mentioned models are useful for estimation of energetic effects of sawing of every kinematics. However, for band saws and circular sawing machines, the chip acceleration power variation as a function of mass flow and tool velocity ought to be included in analysis of sawing at larger cutting speeds. 相似文献
56.
Müller-Graf C Berthe F Grudnik T Peeler E Afonso A 《Fish physiology and biochemistry》2012,38(1):231-241
The Treaty of Amsterdam, in force since 1 May 1999, has established new ground rules for the actions of the European Union
(EU) on animal welfare. It recognizes that animals are sentient beings and obliges the European Institutions to pay full regard
to the welfare requirements of animals when formulating and implementing Community legislation. In order to properly address
welfare issues, these need to be assessed in a scientific and transparent way. The principles of risk assessment in terms
of transparency and use of available scientific data are probably well suited for this area. The application of risk assessment
for terrestrial and aquatic animal welfare is a relatively new area. This paper describes the work developed in the context
of the European Food Safety Authority (EFSA) opinions on the application of a risk assessment methodology to fish welfare.
Risk assessment is a scientifically based process that seeks to determine the likelihood and consequences of an adverse event,
which is referred to as a hazard. It generally consists of the following steps: (i) hazard identification, (ii) hazard characterisation,
(iii) exposure assessment and (iv) risk characterisation. Different approaches can be used for risk assessments, such as qualitative,
semi-quantitative and quantitative approaches. These are discussed in the context of fish welfare, using examples from assessments
done to aquaculture husbandry systems and stunning/killing methods for farmed fish. A critical review of the applications
and limitations of the risk methodology in fish welfare is given. There is a need to develop appropriate indicators of fish
welfare. Yet, risk assessment methodology provides a transparent approach to identify significant hazards and support recommendations
for improved welfare. 相似文献
57.
Jarosław Król Wojciech Pobłocki Tomasz Bockenheimer Piotr Hliwa 《Aquaculture International》2014,22(1):53-62
The effect of supplemented commercial diets with diethylstilbestrol (DES—15, 30 and 60 mg kg?1) and 17 β-estradiol (E2—30 and 60 mg kg?1), two chemicals commonly used in sex reversal procedure in fish, on survival and growth parameters of juvenile European catfish (Silurus glanis) was evaluated. During the two experiments, lasting 28 days each, fish were kept at temperature 25.2–26.5 °C, pH 7.4–9.3 and oxygen concentration 5.0–7.3 mg O2 dm?3. DES supplementation resulted in depressed growth rate of catfish. In experimental groups fed with E2, no negative effect on growth parameters was found. Both chemicals did not result in observed mortality. In all of the experimental DES groups, hepatosomatic index increased significantly, which suggests negative influence on physiological condition of catfish. DES supplementation significantly changed cytological factors of liver cells and caused hepatic alterations in parenchyma, such as vacuolization and blood congestion. Similarly, supplementation of E2 in food resulted in changes in cytological parameters of hepatocytes. However, E2 did not cause pathological changes within the liver tissue. Histological examination of the catfish gonads showed 19 and 38 % of sterile fish after treatment with 30 and 60 mg kg?1 of DES, respectively. The results suggest that DES served in food could be ineffective in hormonal feminization process of European catfish. No disturbances of sex differentiation process after E2 treatment were observed. However, slight feminization effect in the highest level of E2 treatment group was recorded. 相似文献
58.
Journal of Plant Diseases and Protection - The assessment of the effectiveness of resistance sources to fungal diseases is a very important issue allowing to determine the possibilities of... 相似文献
59.
A vegetation survey of semi-permanent plots was conducted between years 1955–1962 and 2005–2009, and aimed to determine floristic changes occurring in beech forests located on a scarcely populated, dense forest area. The survey encompassed all natural beech forest types within the Polish part of the “Eastern Carpathians” International Reserve of Biosphere. A comparison of trends in changes between unmanaged (Bieszczady National Park) and managed (the remaining part of the Biosphere Reserve) forests was attempted. DCA analysis was used for the determination of changes on the community level. The density of vegetation, species richness, frequency of occurrence and cover, and functional groups of species were determined. Much more profound community changes were determined to have occurred in managed beech forests. However, a similar direction in vegetation changes within both managed and unmanaged forests verifies the existence of a regional pattern of changes in beech forests. This regional pattern involves (1) a decrease in the shares of arborescent species within the shrub layer, (2) disturbance of the canopy layer, (3) acidification of the top layer of the soil, (4) change of light conditions, (5) increase in shares of generalist species and decrease in shares of specialist species. A decreasing anthropogenic pressure, aging of forest stands, functioning of large, dense forest areas and sustainable forest management strategies forestry management system mimicking natural deciduous forest disturbance regime constitute factors shaping the regional changes of the forest vegetation. The undergoing changes can lead to biotic and spatial homogenization of the Eastern Carpathian beech forests. 相似文献
60.
Wojciech Mrozik Christian Jungnickel Tomasz Ciborowski William Robert Pitner Jolanta Kumirska Zbigniew Kaczyński Piotr Stepnowski 《Journal of Soils and Sediments》2009,9(3):237-245
Background, aim, and scope Ionic liquids (ILs) are a new class of alternative solvents that make ideal non-volatile media for a variety of industrial
processes such as organic synthesis and biocatalysis, as alternative electrolytes, as phases and phase modifications in separation
techniques, and as alternative lubricants. Once the large-scale implementation of ILs begins, the industrial application will
follow. In view of their great stability, they could slip through classical treatment systems to become persistent components
of the environment, where the long-term consequences of their presence are still unknown. Sorption on soils has a critical
effect on the transport, reactivity, and bioavailability of organic compounds in the environment. So far, the IL sorption
mechanism was investigated solely on the basis of batch experiments, which precluded any assessment of the dynamics of the
process. An understanding of the mobility of ILs in soil columns is crucial for an accurate prediction of their fate in the
soil. The aim of this study therefore was to investigate in detail the mobility of selected imidazolium ILs on three soil
types. Moreover, it was decided to study these processes in soils from the coastal region (Gdańsk, Poland), which usually
constitute a very important geochemical compartment, participating in the transport of contaminants on their way to the sea.
Materials and methods The mobility of alkylimidazolium ILs was investigated in columns containing soils from the coastal area. In addition, the
sorption processes in all the soil systems studied were described isothermally and the equilibrium sorption coefficient was
evaluated. The sorption capacities were determined according to OECD guidelines. Sorption dynamics was studied with use of
polypropylene columns (diameter—10 mm, height—100 mm) packed with 10 g of soil. The ionic liquid solution was then injected
into the soil column and left for 24 h to equilibrate. After this, a solution of 0.01 mM CaCl2 was pumped through the column at a rate of 0.3 ml min–1. Effluents were collected from the bottom of the column and analyzed by HPLC.
Results Sorption was strongest on the Miocene silt and the alluvial agricultural soil and weakest on the podsolic soil and Warthanian
glacial till. The K
d value of long-chain ILs was far higher than that of the short-chain ones. Among the substances tested, hydroxylated ILs were
usually more weakly sorbed. Desorption of ILs is inversely correlated with sorption intensity. The experimental results of
the column tests correlate well with those from batch experiments. In the cases of weakly binding soils, ILs were detected
almost immediately in the eluent. The elution profiles of long-chain ILs indicate that these compounds are very strongly sorbed
onto most soils, although certain amounts were transported through the soil. ILs exhibit a certain mobility in soils: in particular,
salts with short and/or hydroxylated side chains are extremely mobile.
Discussion The results indicate a stronger binding of ILs in the first sorption layer; once the first layer is saturated, there are no
more active sites on the soil surface (no free charged groups); hence, there are no more strong electrostatic binding sites,
and dispersive interaction becomes the dominant interaction potential. The influence of the structure of the ILs, especially
the side-chain length was also confirmed: The K
d value of long-chain ILs was far higher than that of the short-chain ones. The long alkyl side chain facilitates dispersive
interactions with soil organic matter and intermolecular binding, and the build-up of a second layer becomes possible. Among
the substances tested, hydroxylated ILs were usually more weakly sorbed. The hydroxyl group in the side chain can alter the
polarity of the compound so strongly that interaction with organic matter hardly occurs; these salts then remain in the aqueous
phase. The experimental results from the column tests correlate well with those from batch tests. In the weakly binding soils
(with low organic matter), the only binding to the soil surface must be via electrostatic interactions, although intermolecular
van der Waals (ionic liquid–ionic liquid) interactions could also be taking place. The elution profile maxima for organic
rich soils are far smaller than for the other soils. In the former, hydrogen bonding, dispersive and π…π interactions play
a more important part than electrostatic interactions. The rapidly “disappearing” maxima of the elution peaks may indicate
that, after elution of ILs from the second layer, it is difficult to extract further sorbed ILs. In the first layer, the ILs
are bound by much stronger electrostatic interactions. To break these bonds, a greater energy is required than that sufficient
to extract ILs from double sorption layers. Results indicate, moreover, that hydrophobic ILs will be sorbed in the first few
centimeters of the soil; migration into the soil will therefore be almost negligible.
Conclusions Sorption of ILs was the strongest in soils with the highest cation exchange capacities and a high organic content. ILs were
also more strongly bound to the first sorption layer. The sorption coefficients of long-chain ILs were far higher than those
of short-chain ones; usually, hydroxylated derivatives were the least strongly sorbed. Results of soil column experiments
to investigate the mobility of ILs in soils correlated well with those from batch tests, and the elution profiles were also
well correlated with organic matter content. The observed rapidly disappearing elution peak maxima probably indicate that,
after elution of the ILs from the second layer, it is difficult to extract further sorbed compounds.
Recommendations and perspectives Obtained results gave an interesting insight into mobility of ionic liquids in soil columns. However, several questions are
now opened. It is therefore necessary to undertake further studies focused on total cycle of ionic liquids in the soil environment.
This should include their evapotrasporation (lysimeter test), bioaccumulation by plants as well as degradation and transformation
processes (chemical, biological, and physical) typically occurring in soils. Moreover, a further risk assessment of ILs is
desirable since this study has indicated that these compounds, especially those with low lipophilicities, are generally mobile
in the soil matrix. It is already known that short-chain ILs are characterized by low toxicities; should they enter the environment,
they will probably migrate within the soil and pose a risk of contamination of surface and ground waters. This topic is relevant
to the audience. Environmental threat of short-chain ionic liquids is currently unknown. From the predictive point of view,
judging on known low acute toxic effects or high polarities of these compounds seems to be not enough to confirm their “environmental
friendliness”. If we are to fully understand the potential environmental effects, one should also have an insight into long-term
biological consequences of these ionic liquids, including chronic toxicity tests, bioaccumulation, and biotransformation rates
as well as stability against natural elimination mechanisms. 相似文献