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1.
We describe a simple method for measuring cellulose in soil. We used this method to measure the recovery of shredded office
paper and pure medium fiber cellulose added to a Helvetia silt loam clay soil. This method consists of solvating cellulose
from soil with 77% H2SO4 and analysis of the cellulose recovered by the phenol-sulfuric acid carbohydrate assay. Unlike previous related methods the
modifications we propose allow good recovery of cellulose (~99%) and eliminate the need to autoclave the samples. We verified
this method on soil spiked with up to 12% cellulose and found a good linear relationship between the amounts of cellulose
added relative to that recovered. With proper fragmentation and dilution of the acid-treated soil samples, higher concentrations
can be easily measured. We propose this technique as a robust and high throughput means to monitor the degradation of cellulose
in paper spiked soil. 相似文献
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Ana-Maria Pană Liliana-Marinela Ştefan Geza Bandur Paula Sfîrloagă Vasile Gherman Mihaela Silion Marcel Popa Lucian-Mircea Rusnac 《Journal of Polymers and the Environment》2013,21(4):981-994
This paper presents the synthesis, thermal stability and biodegradability of new d-mannose glycopolymers. These glycopolymers have been obtained by free radical bulk copolymerization of d-mannose based glycomonomer, 1-O-(2′-hydroxy-3′-methacryloyloxypropyl)-2,3:5,6-di-O-isopropylidene-d-mannofuranose (Mm), and respectively d-mannose derived oligomer (Mo) with methyl methacrylate and respectively 2-hydroxypropyl methacrylate. The chemical structures of Mm and Mo have been confirmed via FTIR, 1H-NMR and HPLC–MS spectroscopy. The copolymerization process has been investigated using differential scanning calorimetry, which allowed calculating the activation energies by applying Kissinger–Akahira–Sunose method. The glycopolymers are thermally stable, fact assessed by TG analysis; their glass transition temperature exceeds 50 °C, so they are part of the glassy class of polymers. The biodegradability of these glycopolymers has been investigated in vitro, using pure cultures of Zymomonas mobilis and Trichoderma reesei. The glycopolymers lose up to 55 % weight in just 14 days of incubation as their surface and composition is altered by colonies of microorganisms that grow on/into them, fact demonstrated using SEM/EDX. 相似文献
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Gabriela Geanina Vasile Dana Elena Popa Mihaela Buleandră Iulia Gabriela David 《Environmental monitoring and assessment》2018,190(10):609
The evaluation of the cadmium and lead mobile forms from environmental solid samples provides information about their mobility and bioavailability. In the present study, the Cd and Pb mobile fractions were obtained by two modified extraction methods applied to industrial and acidic pH soils or to polluted sediments. In order to highlight that the extraction procedure does not significantly influence the quantitative atomic absorption spectrometric determination of cadmium and lead, the robustness of the extraction methods was evaluated and proven applying a Youden and Steiner factorial design. Within this experimental design, the shaking rate, the shaking time, and the solid/liquid extraction ratio were modified. The measurement uncertainty of the whole analytical procedure was assessed, the contribution of the factors involved in the extraction process being insignificant compared to the other uncertainty sources. The importance of the study is related to the fact that it proves the applicability in the routine laboratory practice of the modified extraction methods by increasing the extraction ratio following thorough optimization and robustness studies. 相似文献
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Mihaela Laura Vica Mirel Glevitzky Gabriela-Alina Dumitrel lia Monica Junie Maria Popa 《Journal of environmental science and health. Part. B》2013,48(3):176-181
Honey is used in food industry and medicine due to its nutritive, therapeutic and dietetic qualities. The microbiological characteristics of 10 unpasteurized honey samples of known origin, collected from Transylvania beekeepers (Romania) were determined. The antibacterial activity of these types of honey against Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis, Salmonella enteritidis, Salmonella anatum, Salmonella choleraesuis, Bacillus cereus, Bacillus subtilis subsp. spizizenii and Listeria monocytogenes strains was studied. The most sensitive to the antibacterial activity were the two staphylococus strains (the largest diameter of inhibition zone was 18 mm) and B. subtilis strains (13.5 mm). The strains of B. cereus, E. coli, L. monocytogenes and Salmonella spp. were found to present resistance to some of the honey samples. Manna, sunflower and polyfloral honeys presented high antibacterial activity while acacia and linden honeys had a lower activity in terms of the number of sensible strains. Statistical analysis shows that the type of strains and the type of honey have influence on the diameter of inhibition. 相似文献
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During recent years, strict environmental regulations have been implemented by governments for the steelmaking industry in order to reduce their environmental impact. In the frame of the ULCOS project, we have developed a new methodological framework which combines the process integrated modelling approach with Life Cycle Assessment (LCA) method in order to carry out the Life Cycle Inventory of steelmaking. In the current paper, this new concept has been applied to the sinter plant which is the most polluting steelmaking process. It has been shown that this approach is a powerful tool to make the collection of data easier, to save time and to provide reliable information concerning the environmental diagnostic of the steelmaking processes. 相似文献
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Cristina L. Popa Simona I. Dontu Erika A. Levei Cristian I. Ioja Ana-Maria Popa Mirela Miclean 《Journal of environmental science and health. Part. B》2020,55(4):329-341
AbstractClosed lakes located in urban parks act as sinks of organochlorine pesticides (OCPs), which have been used, for decades, as insecticides, herbicides and fungicides. The closed lakes from Bucharest, Romania, are periodically managed to prevent eutrophication and accumulation of pollutants. However, it is not known if these practices reduce or enhance the legacy pollution with OCPs. The aim of this study was to explore the spatial variation of OCPs in closed lakes. The total concentration of OCPs in water and sediments ranged between 0.0176 and 37.1?µg/L, and between 122 to 1,890?ng/g, respectively. The concentrations of OCPs were compared with the consensus-based sediment quality guidelines (SQGs) in order to evaluate the ecological risks of sediments. The highest potential adverse effects were associated with γ-HCH exposure. Periodical draining and dredging of lakes lead to the resuspension of contaminants, increasing pesticide bioavailability and accumulation in sediments. In addition, we observed that fluorescent dissolved organic matter (DOM) might influence the OCPs cycle. The quantity and character of fluorescent DOM can provide further insight into OCPs degradation. Also, this study may help urban planners to determine the state of urban waters and to find the best solution for water management. 相似文献
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Gabi Drochioiu Karin Popa Doina Humelnicu Manuela Murariu Ion Sandu Alexandru Cecal 《毒物与环境化学》2013,95(2):221-235
A simple approach was carried out to study the effects of various parameters on high performance liquid chromatography (HPLC) performance of microcystin-LR (MC-LR) analysis in samples from some reservoirs and rivers in Taiwan under simulation conditions. Nature of column and its packing affected the instrument sensitivity. Varied column length indicated the longer column enhanced (C18, 5 μm, 4.6 × 150 mm) HPLC performance. Studies on mobile phase found that ratio and concentration of the mobile phase gradient greatly influenced the peak shape, retention time, and optimal conditions of mobile phase were set at acetonitrile and 0.01M ammonium acetate (30:70). Different compounds were added to mobile phase and their contribution to HPLC spectra was reported. Detection limits were carefully measured and reported. These investigations provide simple and important information that may be applied to HPLC performance for microcystin analysis from natural water systems. 相似文献
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Grčić Ivana Marčec Jan Radetić Lucija Radovan Ana-Maria Melnjak Ivana Jajčinović Igor Brnardić Ivan 《Environmental science and pollution research international》2021,28(15):18354-18367
Environmental Science and Pollution Research - In this work, we present the application of solar photocatalysis for air purification including toxic substances such as ammonia and methane normally... 相似文献