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Of humic substances

N. Masque R. M. Marce and E. Boirull, Chemical removal of humic substances interfering with the on-line solid-phase exti action-liquid chi omatographic determination of polar water pollutants , Chromatographia 4 231-236 (1998). [Pg.375]

The problems involved in the study of humic substances are, as expected, also encountered in the case of fossil fuels. Most C-13 CP/MAS spectra of solid fossil fuels (coals, oil shales) do not exhibit a high level of spectral resolution50,51). They consist essentially of two broad bands — one in the aromatic/olefinic region from about 170 ppm to 95 ppm and one in the aliphatic region from about 90 to —5 ppm relative to TMS. On the other hand, lignite, an imperfectly formed coal, shows a considerable amount of fine structure. [Pg.18]

Perdue EM, NL Wolfe (1982) Modification of pollutant hydrolysis kinetics in the presence of humic substances. Environ Sci Technol 16 847-852. [Pg.45]

Zepp RG, PF Schlotzhauer, RM Sink (1985) Photosensitized transformations involving energy transfer in natural waters role of humic substances. Environ Sci Technol 19 74-81. [Pg.49]

Scott DT, DM McKnight, EL Blunt-Harris, SE Kolesar, DR Lovley (1998) Quinone moieties act as electron acceptors in the reduction of humic substances by humics-reducing microorganisms. Environ Sci Tech-nol 32 2984-2989. [Pg.293]

Mierle G, Ingram R. 1991. The role of humic substances in the mobilization of mercury from watersheds. Water Air Soil Pollut 56 349-357. [Pg.85]

S. Nardi, M. R. Panuccio, M. R. Abenavoli, and A. Muscolo, Auxin-like effect of humic substances extracted from faeces oi Allolohophora Caliginosa and A. rosea. Soil Biol. Biochem. 26 1341 (1994). [Pg.14]

A. Albuzio, and G. Ferrari. Modulation of the molecular size of humic substances by organic acids of the root exudates. Plant Soil 773 237 (1989). [Pg.14]

This chapter focuses on the effects of humic substances present at the rhizo-sphere on plant growth and nutrient uptake. The main structural features of humic substances, their nutritional function, and the capacity to interact with plant metabolism are also presented. [Pg.142]

Humic substances can form complexes with metals, including cationic micronutrients (36), thanks to the presence of electron-donor functional groups in these molecules. It therefore appears evident that due to these properties, humic substances can contribute to the regulation of the chemical balances of metals, thus influencing their solubility (5). With regard to plant availability, the molecular dimension and solubility of humic substances are very important. [Pg.145]

Figure 1 Proposed role of humic substances on iron nutrition of plants possessing dif fereni strategies for iron acquisition. WEHS, water-extractable humic substances, as described in the text. Figure 1 Proposed role of humic substances on iron nutrition of plants possessing dif fereni strategies for iron acquisition. WEHS, water-extractable humic substances, as described in the text.
D. Vaughan and R. E. Malcolm, Influence of humic substances on growth and physiological processes. Soil Organic Matter and Biological Activity (D. Vaughan and... [Pg.153]

M. Schnitzer, Recent findings on the characterization of humic substances extracted from soils from widely differing climatic zones. Proceedings of Symposium on Soil Organic Matter Studies, Braun.schweig, RFG, 1977, pp. 117-131. [Pg.153]

A. Piccolo, S. Nardi, and G. Concheri, Micelle-like conformation of humic substances as revealed by size exclusion chromatography. Chemosphere 33 595 (1996). [Pg.153]

M. De Nobili and Y. Chen, Size exclusion chromatography of humic substances limits, perspectives and prospectives. Soil Sci. 764 825 (1999). [Pg.153]

A. I. Popov and O. G. Chertov, On humic substances as a direct nutritive component of plant-soil trophic system. The Role of Humic Substances in the Ecosystems and in Environmental Protection ( J. Drozd, S. S. Gonet, N. Senesi, and J. Weber, eds.), Polish Society of Humic Substances, Wroclaw, 1997, p. 993. [Pg.154]

Y. Chen and T. Aviad, Effects of humic substances on plant growth. Humic Substances in Soil and Crop Sciences Selected Readings (P. Mac Carthy, C. E. Clapp, R. L. Malcolm, and P. R. Bloom, eds.), American Society of Agronomy and Soil Science Society of America, Madison, Wisconsin, 1990, p. 161. [Pg.155]

G. Concheri, S. Nardi, F. Reniero, and G. Dell Agnola, The effects of humic substances within the Ah horizon of a calcic luvisol on morphological changes related to invertase and peroxidase activities in wheat roots. Plant Soil 179 65 (1996). [Pg.156]

Artinger R, Kienzler B, Schii(31er W, et al. 1998. Effects of humic substances on the 241 Am migration in a sandy aquifer Column experiments with Gorleben groundwater/sediment systems. J Contain Hydrol 35 261-275. [Pg.226]

Stenson, A. C. Landing, W. M. Marshall, A. G. Cooper, W. T. Ionization and fragmentation of humic substances in electrospray ionization Fourier transform-ion cyclotron resonance mass spectrometry. Anal. Chem. 2002, 74, 4397-4409. [Pg.297]

Chemat F, Teunissen PGM, Chemat S, Bartels PV (2001) Sono-oxidation treatment of humic substances in drinking water. Ultrason Sonochem 8 247-250... [Pg.66]

Bailey G.W., Akim L.G., Shevchenko S.M. Predicting chemical reactivity of humic substances for minerals and xenobiotics use of computational chemistry, scanning probe microscopy, and virtual reality. In Humic Substances and Chemical Contaminants, C.E. Clapp, M.H.B. Hayes, N. Senesi, P.R. Bloom, P.M. Jardine, eds. Madison, WI Soil Science Society of America, Inc., 2001. [Pg.330]

Soil Mineral Catalysis and the Formation of Humic Substances...10... [Pg.4]

Malcolm RE, Vaughan D (1979) Effects of humic acid fraction on invertase activities in plant tissues. Soil Biol Biochem 11 65-72 Malcolm RL (1989) Application of solid-state 13C NMR spectroscopy to geochemical studies of humic substances. In Hayes MHB, MacCarthy P, Malcolm RL, Swift RS (eds) Humic substances II. In search of structure. Wiley, Chichester, UK, pp 339-372... [Pg.34]

Shindo H, Huang PM (1982) Role of Mn(IV) oxide in abiotic formation of humic substances in the environment. Nature (London) 298 363-365... [Pg.36]

Perminova I, Grechishcheva N, Peterosyan V (1999) Relationships between structure and binding affinity of humic substances for polycyclic aromatic hydrocarbons relevance of molecular descriptors. Environ Sci Technol 33 3781-3787... [Pg.141]

Tanaka F, Fukushima M, Kikuchi A, Yabuta H, Ichikawa H, Tatsumi K (2005) Influence of chemical characteristics of humic substances on the partition coefficient of a chlorinated dioxin. Chemosphere 58 1319-1326... [Pg.142]

Humic acids (HA) and fulvic acids (FA) are the main components of humic substances (HS), which are the most chemically and biochemically active and widely spread fractions of nonliving natural organic matter in all terrestrial and aquatic environments. They comprise a chemically and physically heterogeneous group of substances with colloidal, polydis-persed, polyelectrolyte characteristics and mixed aliphatic and aromatic nature (Senesi and Loffredo 1999). [Pg.282]

Table 1. Origin and nature of humic substances used with corresponding codes, abbreviations and concentrations... Table 1. Origin and nature of humic substances used with corresponding codes, abbreviations and concentrations...
Origin and nature of humic substances IHSS Code Abbreviation Concentrations used (mgL-1)... [Pg.284]

See other pages where Of humic substances is mentioned: [Pg.502]    [Pg.170]    [Pg.142]    [Pg.143]    [Pg.146]    [Pg.148]    [Pg.149]    [Pg.150]    [Pg.152]    [Pg.341]    [Pg.157]    [Pg.132]    [Pg.11]    [Pg.196]    [Pg.203]    [Pg.299]    [Pg.300]   


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