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Shadpour Mallakpour Fatemeh Zeraatpisheh Mohammad R. Sabzalian 《Journal of Polymers and the Environment》2012,20(1):117-123
In this paper we studied the synthesis of biodegradable optically active poly(ester-imide)s containing different amino acid
residues in the main chain. These pseudo-poly(amino acid)s were synthesized by polycondensation of N,N′-(pyromellitoyl)-bis-l-tyrosine dimethyl ester as a diphenolic monomer and two chiral trimellitic anhydride-derived diacid monomers containing s-valine and l-methionine. The direct polycondensation reaction of these diacids with aromatic diol was carried out in a system of tosyl
chloride (TsCl), pyridine (Py) and N,N′-dimethylformamide (DMF) as a condensing agent. The structures and morphology of these polymers were studied by FT-IR, 1H-NMR, powder X-ray diffraction, field emission scanning electron microscopy (FE-SEM), specific rotation, elemental and thermogravimetric
analysis (TGA) techniques. TGA profiles indicate that the resulting PEIs have a good thermal stability. Morphology probes
showed these polymers were noncrystalline and nanostructured polymers. The monomers and prepared polymers were buried under
the soil to study the sensitivity of the monomers and the obtained polymers to microbial degradation. The high microbial population
and prominent dehydrogenase activity in the soil containing polymers showed that the synthesized polymers are biologically
active and microbiologically biodegradable. Wheat seedling growth in the soil buried with synthetic polymers not only confirmed
non-toxicity of polymers but also showed possibility of phyto-remediation in polymer-contaminated soils. 相似文献
2.
ROUABHI Rachid DJEBAR-BERREBBAH H DJEBAR MR 《应用与环境生物学报》2006,12(4):514-517
Harmful bugs affect food production,directly by the qualitativeor quantitative reduction of the harvests,or indirectly while servinglike vectors of several illnesses of the plants and human[1].Many chemical products are used by human for a long time inthe… 相似文献
3.
Shadpour Mallakpour Farhang Tirgir Mohammad R. Sabzalian 《Journal of Polymers and the Environment》2010,18(4):685-695
Ionic liquids (ILs) have been accepted as ‘green’ alternatives to the organic solvents in a range of synthesis, catalysis
and electrochemistry, because of their distinctive chemical and physical properties. In this investigation, N,N′-(pyromellitoyl)-bis-l-tyrosine dimethyl ester as a chiral bioactive diphenolic monomer was prepared in three steps. The polycondensation of this
monomer with various aromatic and aliphatic diisocyanates such as 4,4′-methylene-bis-(4-phenylisocyanate) (6a), toluylene-2,4-diisocyanate (6b), isophorone diisocyanate (6c) and hexamethylene diisocyanate (6d) were carried out in the presence of tetrabutylammonium bromide as a molten IL under microwave irradiation conditions and
was compared with polymerization in traditional solvent like N-methyl-2-pyrrolidone. The results show that IL efficiently absorbs microwave energy, thus leading to a very high heating
rate. Thus IL method is safe and green since toxic and volatile organic solvents were eliminated. All of the novel poly(urethane-imides)
(PUIs) showed good solubility in various organic solvents. The obtained new polymers were characterized with FT-IR, 1H-NMR, elemental and thermogravimetric analysis techniques. Thermogravimetric analysis (TGA) of two representative PUIs demonstrated
that they are rather thermally stable. In vitro toxicity studies showed that the synthetic materials are biologically active
and they are nontoxic to microbial growth then could be classified as bioactive and biodegradable compounds. 相似文献
4.
The results of analyses for polychlorodibenzofuran (PCDF) content in two samples of polychlorobiphenyl (PCB) from used electrical transformers are presented and discussed. In neither sample was there evidence for enhanced PCDF concentrations even though one of them had been subjected to overheating while in service. 相似文献
5.
Results of analyses of eight samples of technical pentachlorophenol conducted by three different analytical methods are presented and discussed. 相似文献
6.
Phytoremediation of an aged petroleum contaminated soil using endophyte infected and non-infected grasses 总被引:2,自引:0,他引:2
Soleimani M Afyuni M Hajabbasi MA Nourbakhsh F Sabzalian MR Christensen JH 《Chemosphere》2010,81(9):1084-1090
Phytoremediation is a promising technique for cleaning petroleum contaminated soils. In this study, the effects of two grass species (Festuca arundinacea Schreb. and Festuca pratensis Huds.), infected (E(+)) and non-infected (E(-)) by endophytic fungi (Neotyphodium coenophialum and Neotyphodium uncinatum, respectively) on the degradation of petroleum hydrocarbons in an aged petroleum contaminated soil was investigated. Plants were grown in the soil for 7 months and unplanted soil considered as control. At the end of the experiment, total and oil-degrading bacteria, dehydrogenase activity, water-soluble phenols, total petroleum hydrocarbons (TPH) and polycyclic aromatic hydrocarbons (PAHs) contents were measured in the soil. The results demonstrated that E(+) plants contained more root and shoot biomass than E(-) plants and created higher levels of water-soluble phenols and dehydrogenase activity in the soil, while there was no significant difference in bacterial counts of planted soils. Planting stimulated total and oil-degrading bacterial numbers, dehydrogenase activity and the soil content of water-soluble phenols. Regardless of endophyte infection, PAH and TPH removal in the rhizosphere of plants were 80-84 and 64-72% respectively, whereas the removals in controls were 56 and 31%, respectively. It was revealed that TPHs in retention time range of n-alkanes with C(10)-C(25) chain lengths and TPH were more degraded in the rhizosphere of E(+) plants compared to E(-) ones. Thus, grasses infected with endophytic fungi could be more efficient for removal of TPH from oil-contaminated soils. 相似文献
7.
Shadpour Mallakpour Kazem Banihassan Mohammad R. Sabzalian 《Journal of Polymers and the Environment》2013,21(2):568-574
In this paper chiral bioactive poly(amide–imide)s (PAI)s were synthesized from four different diacids containing chiral amino acids with 4,4′-methylene bis(3-chloro 2,6-diethylaniline) as a diamine via direct polycondensation reaction in a system of tetra-n-butylammonium bromide and triphenyl phosphite as a condensing agent. The structures of these polymers were confirmed by FT-IR, 1H-NMR, specific rotation, elemental and thermogravimetric analysis (TGA) techniques. TGA showed that the 10 % weight loss temperature in a nitrogen atmosphere was more than 378 °C, which indicates that the resulting PAIs have a good thermal stability. The biodegradability of the monomers and prepared polymers was investigated in culture media and soil burial test for assessment of the susceptibility of these compounds to microbial degradation. The results showed that the synthesized monomers and theirs derived polymers are biologically active and nontoxic to microbial growth. 相似文献
8.
Wood samples treated with technical pentachlorophenol (PCP), technical sodium pentachlorophenoxide (NaPCP) and octachlorodibenzo-p-dioxin have been exposed outdoors for periods up to years. Analysis of extracts from the samples show that photolytic reductive dechlorination of highly chlorinated dibenzo-p-dioxins to less chlorinated isomers occurs. However there is no discernible increase in polychlorodibenzo-p-dioxin concentrations in the technical PCP treated wood presumably because further photolytic reactions and volatilisation compete effectively with the photolytic formation. There is no evidence for formation of octachlorodibenzo-p-dioxin (OCDD) in technical PCP treated wood in this study, probably because photolytic destruction and volatilisation compete effectively with formation reactions when the initial OCDD concentration is relatively high. 相似文献
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