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981.
Szczygłowska M Piekarska A Konieczka P Namieśnik J 《International journal of molecular sciences》2011,12(11):7760-7771
In recent decades, serious contamination of soils by heavy metals has been reported. It is therefore a matter of urgency to develop a new and efficient technology for removing contaminants from soil. Another aspect to this problem is that environmental pollution decreases the biological quality of soil, which is why pesticides and fertilizers are being used in ever-larger quantities. The environmentally friendly solutions to these problems are phytoremediation, which is a technology that cleanses the soil of heavy metals, and biofumigation, a process that helps to protect crops using natural plant compounds. So far, these methods have only been used separately; however, research on a technology that combines them both using white cabbage has been carried out. 相似文献
982.
Stocka J Tankiewicz M Biziuk M Namieśnik J 《International journal of molecular sciences》2011,12(11):7785-7805
Pesticides are among the most dangerous environmental pollutants because of their stability, mobility and long-term effects on living organisms. Their presence in the environment is a particular danger. It is therefore crucial to monitor pesticide residues using all available analytical methods. The analysis of environmental samples for the presence of pesticides is very difficult: the processes involved in sample preparation are labor-intensive and time-consuming. To date, it has been standard practice to use large quantities of organic solvents in the sample preparation process; but as these solvents are themselves hazardous, solvent-less and solvent-minimized techniques are becoming popular. The application of Green Chemistry principles to sample preparation is primarily leading to the miniaturization of procedures and the use of solvent-less techniques, and these are discussed in the paper. 相似文献
983.
Jacek Andrzejewski Marek Szostak Mateusz Barczewski Janusz Krasucki Tomasz Sterzynski 《应用聚合物科学杂志》2014,131(23)
The results of this work relate to the use of co‐extrusion technology in the preparation of monocomposite pellets. The low‐melting polypropylene copolymer was used as a matrix material. The high strength polypropylene fibers were used as a fibrous reinforcement. Research confirms the possibility to produce the pellets with fibrous structure. The prepared composite material in the form of pellets was processed and shaped using the injection molding technology. Obtained samples were subjected to mechanical testing in the static tensile test and dynamic mechanical analysis. Research complements microscopic observation of scanning electron microscopy. The measurement results confirm the reinforcing effect of the fibers. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41180. 相似文献
984.
Robert Pietrzak Piotr Nowicki Justyna Kaźmierczak Izabela Kuszyńska Joanna Goscianska Jacek Przepiórski 《Chemical Engineering Research and Design》2014
A method for obtaining activated carbons from cherry stones by chemical activation with NaOH is described. Carbonaceous adsorbents were obtained by two methods of activation (physical mixing and impregnation) and two variants of thermal treatment (at a constant or increasing temperature). Cherry stones were proved to be effective cheap precursors of carbon adsorbents, characterised by large pore volume (ranging from 0.22 to 0.47 cm3/g) and good sorption abilities (iodine number from 343 to 996 mg/g). The activated carbons obtained usually have strongly microporous structure and acidic surface character. The best physicochemical properties and adsorption properties towards iodine were found to be shown by the carbon samples obtained by physical mixing of the precursor or char with the activating agent followed by activation at 600 °C. 相似文献
985.
The influence of three fire retardant agents: Polichron, Pyrolak W-10, and Pyrolak W-10 + Pyrolak W-1 on smoke density of pine wood, plywood, soft hardboard and tough hardboard was investigated. Surface samples of 25 cm2 (5 × 5 cm) were used and the heat flux was varied over the range of 1.0 to 4.0 W/cm2.
Reference: Tadeusz Cisek and Jacek Piechocki, Influence of Fire Retardants on Smoke Generation from Wood and Wood Derived Materials,Fire Technology, Vol. 21, No. 2, May 1985, p. 122. 相似文献
986.
Kapala J Karpińska M Mnich Z Szpak A Milewski R Citko D 《Radiation protection dosimetry》2008,130(2):178-185
The measurements of radioactive caesium contents in bottom sedimentswere carried out in four lakes. First samples (47) were takenin 1992–95. The repeat sampling (109) was performed fromthe same places in 2005. We examined eight chosen areas in theselakes. In six of them, we observed statistically significantdifferences in the level of radioactive caesium. It indicatesthe permanent decrease in the level of 137Cs. The mean annualdecrease in the level of radioactive caesium, taking into considerationthe radioactive decay, was from 4.2 to 7.8%. In two areas ofthe profundal zone, we did not observe statistically significantdifferences in the level of radioactive caesium (lakes Garbasand Rogale Wielkie). Taking into consideration the radioactivedecay of caesium, it means about the appearance of the processof accumulation of 137Cs in these areas. 相似文献
987.
Paczoska-Eliasiewicz HE Gertler A Proszkowiec M Proudman J Hrabia A Sechman A Mika M Jacek T Cassy S Raver N Rzasa J 《Reproduction (Cambridge, England)》2003,126(6):739-751
Thirty-four-week-old laying hens received injections of recombinant chicken leptin to assess the role of leptin in avian ovarian function. In the first experiment, the hens (n=60) were divided into three groups: (i). fed ad libitum; (ii). fasted; and (iii). fasted + leptin. Hens were fasted for 5 days and those treated with leptin received 250 microg leptin kg-1 body weight twice a day, i.p. In the second experiment, the hens (n=72) were divided into four groups: (i). fed ad libitum; (ii). fasted; (iii). fasted + leptin given only during fasting (5 days); or (iv). fasted and leptin given during both fasting and 5 days of re-feeding (10 days). LH was measured in blood plasma, and progesterone and oestradiol were measured in blood plasma and the ovary by radioimmunoassay. Apoptosis was examined in the walls of the three largest yellow hierarchical follicles (F3-F1; F38-12 mm), and the granulosa layer of F3 follicles. The expression of leptin receptor in the granulosa layer of F2 and F1 follicles was barely detectable. This was in contrast to a much higher expression of leptin receptor maintained in the theca layer of F3-F1 follicles. The present results indicate that in chickens leptin might be involved in the adaptation to starvation due to attenuation of follicular apoptosis. The presence of leptin receptors in the ovary indicates the possibility of a peripheral effect of the hormone. 相似文献
988.
Shela Gorinstein Sumitra PoovarodomHanna Leontowicz Maria LeontowiczJacek Namiesnik Suchada VearasilpRatiporn Haruenkit Pramoj RuamsukeElena Katrich Zev Tashma 《Food research international (Ottawa, Ont.)》2011,44(7):2222-2232
The aim of this research was to investigate the bioactivity of durian, snake fruit and mangosteen, rare exotic Thai fruits. These fruits were compared among them and with conventional fruits: durian with mango and avocado, and snake fruit with mangosteen and kiwifruit in order to find the preferable diet for human consumption. The contents of polyphenols, flavonoids, flavanols, tannins, anthocyanins, ascorbic acid and carotenoids, and the level of antioxidant potential by ABTS, DPPH, FRAP and CUPRAC in different extracts (methanol, water, acetone, and hexane) were determined. The presence of polyphenols (flavonoids and phenolic acids) in the investigated samples was characterized by Fourier transform infrared (FT-IR) spectroscopy and three-dimensional fluorimetry (3D-FL).The in vivo studies were carried out on 25 male Wistar rats, divided into 5 diet groups, each of 5. During 30 days of the experiment the rats of all 5 groups were fed basal diet (BD), which included wheat starch, casein, soybean oil, vitamin and mineral mixtures. The rats of the Control group were fed only the BD. The BD of the other 4 groups was supplemented with 1% of nonoxidized cholesterol (NOC) (Chol group), 1% of NOC in each group and 5% of lyophilized fruits: durian (Chol/Durian), snake fruit (Chol/Snake), mangosteen (Chol/Mangosteen). After the experiment diets supplemented with exotic fruits significantly hindered the rise in plasma lipids and hindered the decrease in the plasma antioxidant activity. In conclusion, the contents of bioactive compounds and the antioxidant potential are relatively high in the studied fruits and varied among them depending on the extraction procedure. FT-IR and 3D-FL can be used as additional tools for identification and comparison of bioactive compounds. Supplementation of diets with exotic fruits positively affects plasma lipid profile and antioxidant activity in rats fed cholesterol-containing diets. 相似文献
989.
Chicken-meat processing generates large quantities of by-products (backs, necks, etc.). Dark chicken-meat processing by-products present the lowest value and greatest challenge. Therefore, recovery of functional proteins from this source for inclusion in food products resembling those from light chicken-meat presents the greatest value addition and opportunity. Novel isoelectric solubilization/precipitation (ISP) was applied to model, dark chicken-meat processing by-products (skin-on bone-in chicken drumsticks) to recover muscle proteins. Thermal denaturation (endothermic transitions), gelation (elasticity, G′), and fundamental texture properties (shear stress and strain at mechanical fracture) of the ISP-recovered proteins were determined with differential scanning calorimetry (DSC), dynamic rheometer, and torsion test, respectively; and compared to boneless skinless chicken breast. Endothermic transition of myosin was not detected only when TiO2 was not added, while the ISP-recovered proteins with TiO2 showed small myosin peak and large actin peak. However, the level of TiO2 addition did not affect thermal transition/denaturation of the ISP-recovered proteins. The ISP-recovered proteins had a greater transition for actin compared to chicken breast, suggesting that ISP predisposes this protein to thermal denaturation. Similar to endothermic transitions, elasticity (G′) generally increased when TiO2 was added to the ISP-recovered proteins. Gels made of chicken breast had the highest (P < 0.05) shear stress (i.e., gel strength), but gels made of the ISP-recovered chicken proteins had greater (P < 0.05) shear strain (i.e., gel cohesiveness). Addition of TiO2 to the ISP-recovered proteins resulted in increased (P < 0.05) gel strength. Based on the present study, addition of TiO2 is suggested for the development of restructured food products based on proteins recovered from dark chicken-meat processing by-products using ISP. Although the results of this study point towards a novel food product, further studies are recommended. 相似文献
990.
Jacek J. Jasieniak Jason Seifter Jang Jo Tom Mates Alan J. Heeger 《Advanced functional materials》2012,22(12):2594-2605
A simple, solution‐processed route to the development of MoOx thin‐films using oxomolybdate precursors is presented. The chemical, structural, and electronic properties of these species are characterized in detail, within solution and thin‐films, using electrospray ionization mass spectrometry, grazing angle Fourier transform infrared spectroscopy, thermogravimetric analysis, atomic force microscopy, X‐ray photoelectron spectroscopy, and ultraviolet photoelectron spectroscopy. These analyses show that under suitable deposition conditions the resulting solution processed MoOx thin‐films possess the appropriate morphological and electronic properties to be suitable for use in organic electronics. This is exemplified through the fabrication of poly(3‐hexylthiophene):[6,6]‐phenyl C61 butyric acid methyl ester (P3HT:PC61BM) bulk heterojunction (BHJ) solar cells and comparisons to the traditionally used poly(3,4‐ethyldioxythiophene)/poly(styrenesulfonate) anode modifying layer. 相似文献