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The study uses the Fourier transform infrared spectroscopy method to evaluate the influence of phosphogypsum from the soil on the growth and accumulation of nutrients in Spinacia oleracea. Attenuated total reflectance spectra of Spinacia oleracea roots and stems originated from plants cultivated on 28% to 52% phosphogypsum enriched soil have been studied in the 4000–600 cm?1 area. The structure of the infrared absorption bands for spinach roots and stems and for the soil where plants were grown was analyzed. Thus, it was observed that phosphorus–oxygen bonds contribution can be identified both in roots and stems absorption spectra. The significance of the research is the possibility to use the infrared investigation as rapid technique, particularly useful for agriculture, to study the extraction and assimilation process of the compounds containing phosphorus and nitrogen from the soil in which the spinach seedlings grew. In the case of this study, it was observed that the absorption of phosphorus in the spinach roots and stems has not the same effect. The analysis of obtained data indicated that the assimilation of phosphorus from phosphogypsum enriched soil induces changes in spinach roots structure that are most likely due to an increase synthesis of proteins, rather than to a decrease in carbohydrates quantity. 相似文献
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ABSTRACT Revealing molecular alterations induced on kiwifruit under UV-Vis irradiation requires a discussion of biochemical-cell infrared (IR) fingerprint (900 cm?1–1800 cm?1) bands characteristic of nucleic acids. FTIR-ATR spectroscopy and statistics and nondestructive methods for screening exposure effects induced by irradiation were used. There the irradiation influence on the main molecular bonds (i.e., ν(C-C), νs(PO2?) and νas(PO2?)) can be observed. Regression methods were used for statistical investigations. Two categories of variables were used: the absorbance measured at fixed wavenumber variables and the exposure dose. The bivariate correlations, partial correlations, and polynomial regression methods from SPSS were used for statistical investigations. The obtained results show that FTIR-ATR, in correlation with statistics techniques, might be useful to assess immediate radiation and oxidative-induced damage to nucleic acids. In this case IR spectroscopy can be used successfully to study conformational changes during DNA reversible denaturation especially on the sugar-phosphate vibrations domain. 相似文献
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Stan Stelian Chisamera Mihai Riposan Iulian Stefan Eduard Neacsu Loredana Cojocaru Ana Maria Stan Iuliana 《Journal of Thermal Analysis and Calorimetry》2019,138(4):2529-2540
Journal of Thermal Analysis and Calorimetry - Simultaneous thermal and contraction/expansion analysis of hypoeutectic grey (lamellar graphite) and ductile (nodular graphite) cast irons... 相似文献
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Two triphenylamine-based polymers were successfully prepared by the interfacial and microemulsion oxidative polymerization of triphenylamine and 4-(diphenylamino)benzyl 2-bromo-2-methylpropanoate. Ammonium peroxodisulfate ((NH4)2S2O8) was used as a chemical oxidant and dichloromethane/water was used as a solvent. Sodium dodecyl benzene sulfonate was employed as a surfactant in the microemulsion system. Polytriphenylamines were characterized via Fourier transform infrared (FTIR) spectra and 1H-NMR and UV–vis absorption spectroscopy. Molecular weights were determined by gel permeation chromatography and redox properties were studied by cyclic voltammetry. The surface morphology of thin polymer films was determined by atomic force microscopy. 相似文献
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Lagrost C Alcaraz G Bergamini JF Fabre B Serbanescu I 《Chemical communications (Cambridge, England)》2007,(10):1050-1052
Vinyl-terminated heptapodyl beta-cyclodextrins react with hydrogenated silicon surfaces to generate covalently-bound molecular recognition devices. 相似文献
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Loredana-Mihaela Dobre Anicuţa Stoica-Guzun Marta Stroescu Iuliana Mihaela Jipa Tǎnase Dobre Mariana Ferdeş Ştefana Ciumpiliac 《Chemical Papers》2012,66(2):144-151
Antimicrobial packaging protects the product from the external environment and microbial contamination, conferring numerous
advantages on human health. Interest in biopolymers as packaging materials has considerably increased recently. Bacterial
cellulose is an interesting biomaterial produced as nanofibrils by Acetobacter xylinium and is a promising candidate due to its remarkable properties. New composite materials with antimicrobial properties were
developed in this work, containing poly(vinyl alcohol) (PVA) as polymer matrix and ground bacterial cellulose (BC) as reinforcing
fibres. Sorbic acid was used as an antimicrobial agent because it is a preservative recognised in the food industry. The materials
obtained were studied using Fourier-transformed infrared spectroscopy (FTIR). The swelling rate of the composites was also
measured. Release experiments of sorbic acid from the composite films into water were performed and the mass transfer phenomena
were investigated using Fick’s law of diffusion. The antimicrobial effect was tested against Escherichia coli K12-MG1655. The results obtained indicated that the new biocomposite films could be promising antimicrobial food packaging
materials. 相似文献
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Anicuta Stoica-Guzun Marta Stroescu Iuliana Jipa Loredana Dobre Sorin Jinga Traian Zaharescu 《Macromolecular Symposia》2012,315(1):198-204
The development of biodegradable packaging materials, especially from renewable resources is a constant preoccupation of nowadays, because of the environmental problems caused by synthetic polymers. The combination of cellulose with other polymeric materials could be an ecologic alternative and a way to use renewable resources for food packaging. Bacterial cellulose which is produced by microbial fermentation is also a promising material which can be used not only in biomedical application, but also as food packaging material. In this research different composite films between poly(vinyl alcohol)-bacterial cellulose (PVA-BC) were obtained by casting method. The obtained films were UV irradiated for different periods of times from 1 to 10 hours, using a mercury lamp, Philips TUV-30, emitting light mainly at 254 nm. Changes in FT-IR spectra before and after UV irradiation and the modification of transparency and of the swelling characteristics of the films were observed. As it was expected the composites materials are sensitive at UV exposure. 相似文献