Reply to: Preston, C.M. (2000): Comment on: "Application of 13C CPMAS NMR techniques in 'Petroleum residues as water-repellent substances in weathered nonwettable oil-contaminated soils' (Roy et al. 1999) and recent related studies"

2000 ◽  
Vol 80 (1) ◽  
pp. 231-234 ◽  
Author(s):  
W. B. McGill ◽  
J. L. Roy
Keyword(s):  
Contaminated Soils ◽  
Water Repellent ◽  
13C Cpmas Nmr ◽  
Petroleum Residues ◽  
Nmr Techniques

not available

Petroleum residues as water-repellent substances in weathered nonwettable oil-contaminated soils

1999 ◽  
Vol 79 (2) ◽  
pp. 367-380 ◽  
Author(s):  
Julie L. Roy ◽  
William B. McGill ◽  
Marvin D. Rawluk
Keyword(s):  
Soil Water ◽  
Contaminated Soils ◽  
Impact Ionization ◽  
Water Repellency ◽  
Solvent Mixture ◽  
Water Repellent ◽  
Soil Water Repellency ◽  
Petroleum Origin ◽  
Soil Hydrophobicity ◽  
Gas Chromatography Mass Spectroscopy

Some soils develop severe water repellency several years or decades following oil contamination. We previously reported on the characteristics of three such soils. Here we report on the characteristics of putative water-repellent substances in them. We examined the effectiveness of various polar, nonpolar and amphiphilic solvents for removal of water-repellent substances in three nonwettable soils. Only the amphiphilic solvent mixture isopropanol/14.8 M ammonia (7:3, vol/vol) (IPA/NH4OH) completely eliminated soil water repellency in all three soils. We thus define putative water-repellent substances as those substances whose removal from soil by IPA/NH4OH removes water repellency. High-resolution CPMAS 13C-NMR spectroscopy and thermal desorption followed by conventional gas chromatography/mass spectroscopy with electron impact ionization (GC/EI/MS) and GC/MS with chemical ionization (GC/CI/MS) were used to characterize extracted putative water-repellent substances. We conclude that: (i) the identified representatives of these substances consist mostly of homologous series of long-chain and polycyclic aliphatic organic compounds; namely, n-fatty acids, n-alkanes, and cycloalkanes, and that (ii) they are of petroleum origin rather than plant or microbial origin. Key words: Soil hydrophobicity, petroleum hydrocarbons, soil water repellency, amphiphilic solvents, crude oil, nonwettable soil

Sorption of a Xenobiotic Contaminant in Clean and Petroleum-Contaminated Soil: Roles of Water and Xenobiotic Size

2006 ◽  
Vol 3 (2) ◽  
pp. 124
Author(s):  
Tiona R. Todoruk ◽  
Cooper H. Langford
Keyword(s):  
Contaminated Soils ◽  
Model Compound ◽  
Water Repellent ◽  
Sorption Behavior ◽  
Complex Phenomenon ◽  
Soil Composition ◽  
Term Retention ◽  
Petroleum Contaminated Soil ◽  
Labile Component ◽  
Sorption Phenomenon

Environmental Context.Soil uptake of xenobiotics (e.g. pesticides) can be a complex phenomenon where it is useful to distinguish readily reversible sorption from longer-term retention. A scheme for doing this using fluorescence detection is presented here, along with application to uptake of a model compound in clean and oil-contaminated soils. Both the wetting of the soil and the size of the xenobiotic seem to be important. The present data concern uptake. Desorption is expected to exhibit dependencies on similar factors. The data have implications for understanding persistence. Abstract.Description of sorption of xenobiotics (e.g. pesticides) into soils requires identification of at least two kinetic components. In the present work, the distinction between ‘labile’ (readily reversible) and ‘non-labile’ (not reversible) uptake was extended, introducing a fluorescence-based method using 9-anthracenepropionic acid as a probe molecule. Study of clean, oil-contaminated wettable, and water-repellent oil-contaminated soils has given new perspectives into the role that water plays in xenobiotic uptake. Non-labile uptake is unimportant in the water-repellent soils; however, non-labile components are observed in both clean and wettable oil-contaminated samples, supporting earlier suggestions that water plays a role in non-labile uptake processes. A soil pre-exposed to water exhibited different labile sorption behavior from one where xenobiotic was added simultaneously with water to an air-dried soil. The comparatively rapid non-labile component of uptake (3 days) of 9-anthracenepropanoic acid by a clean soil contrasted with much longer times in earlier studies of 2,4-D and atrazine. This pointed to another factor influencing the sorption phenomenon. Literature data supports a suggestion that the non-labile component of xenobiotic sorption may be more strongly influenced by the size of the xenobiotic than by the structure (e.g. polarity) of the xenobiotic or soil composition.

Mitochondrial matrix calcium ions regulate energy production in myocardium: A cytochemical study

1990 ◽  
Vol 48 (2) ◽  
pp. 166-167
Author(s):  
W.A. Jacob ◽  
R. Hertsens ◽  
A. Van Bogaert ◽  
M. De Smet
Keyword(s):  
Energy Metabolism ◽  
Calcium Ions ◽  
Energy Production ◽  
Regulation Of Respiration ◽  
Free Calcium ◽  
Mitochondrial Matrix ◽  
Cytochemical Study ◽  
Nmr Techniques

In the past most studies of the control of energy metabolism focus on the role of the phosphorylation potential ATP/ADP.Pi on the regulation of respiration. Studies using NMR techniques have demonstrated that the concentrations of these compounds for oxidation phosphorylation do not change appreciably throughout the cardiac cycle and during increases in cardiac work. Hence regulation of energy production by calcium ions, present in the mitochondrial matrix, has been the object of a number of recent studies.Three exclusively intramitochondnal dehydrogenases are key enzymes for the regulation of oxidative metabolism. They are activated by calcium ions in the low micromolar range. Since, however, earlier estimates of the intramitochondnal calcium, based on equilibrium thermodynamic considerations, were in the millimolar range, a physiological correlation was not evident. The introduction of calcium-sensitive probes fura-2 and indo-1 made monitoring of free calcium during changing energy metabolism possible. These studies were performed on isolated mitochondria and extrapolation to the in vivo situation is more or less speculative.

Water-repellent coatings could make de-icing a breeze

Nature ◽  
2017 ◽  
Author(s):  
Mark Zastrow
Keyword(s):  
Water Repellent

Water repellent also absorbs

Nature ◽  
2003 ◽  
Author(s):  
Philip Ball
Keyword(s):  
Water Repellent

Isolation of isoflavonoids from Amphimas pterocarpoides and structure elucidation using LC-HRMSn and NMR techniques

Planta Medica ◽  
2010 ◽  
Vol 76 (12) ◽  
Author(s):  
J Tchoumtchoua ◽  
M Halabalaki ◽  
D Njamen ◽  
J Mbanya ◽  
L Skaltsounis
Keyword(s):  
Structure Elucidation ◽  
Nmr Techniques

Effect of chelants on the lead and copper uptake of maize from contaminated soils

2013 ◽  
Vol 62 (2) ◽  
pp. 373-386 ◽  
Author(s):  
György Czira ◽  
László Simon ◽  
György Vincze ◽  
József Koncz ◽  
Gyula Lakatos
Keyword(s):  
Contaminated Soils ◽  
Copper Uptake

Magyarországon a robbanóanyaggal és lőszerszármazékokkal szennyezett területek kármentesítése környezetvédelmi és nemzetgazdasági érdek. Egy hazai lőtérről, illetve lőszer-megsemmisítő telepről vett talajban 900 mg·kg−1 ólom- és 133 mg·kg−1 rézszennyeződést mértünk. A fitoextrakció célja, hogy a növényi szervekbe helyezzük át a nehézfémeket, lecsökkentve ezzel a mobilis, toxikus elemkészletet a szennyezett talajokban. Megvizsgáltuk, hogy egy lőszerszármazékokkal szennyezett talajba, illetve ólommal mesterségesen elszennyezett talajba kijuttatott kelátképzőszerekkel (EDTA, EGTA, citromsav) indukálható-e, megnövelhető-e a növényi szervek Pb- és Cu-akkumulációja?Tenyészedény-kísérletünkben kukoricát neveltünk a fenti ólommal és rézzel elszennyezett lőtéri talajon, illetve a közelben gyűjtött szennyezetlen talajt mesterségesen szennyeztük el 100 mg·kg-1 ólommal. Míg a kontroll (kelátképzővel nem kezelt) szennyezett talajon fejlődő kukorica gyökerében 554 μg·g−1 ólom volt mérhető, addig az EDTA hatására a gyökerekben 4611 μg·g−1-ra (több mint nyolcszorosára), a hajtásokban pedig 158-ról 302 μg·g−1-ra (91%-kal) nőtt az ólomkoncentráció. Mindkét változás statisztikailag szignifikánsnak bizonyult. Az EGTA a Cufelvételt serkentette; a kontrollkultúrák gyökerében 516 μg·g−1, a kezelt kultúrákban viszont 1063 μg·g−1 értéket mértünk (ez kétszeres szignifikáns növekmény). A hajtásokban 69%-kal, 29,9-ról 50,7 μg·g−1-ra emelkedett a réztartalom, ez azonban nem bizonyult statisztikailag szignifikánsnak. A citromsav az ólom hajtásokba történő áthelyeződését nem indukálta, rézfelvétel-serkentő hatása csak a gyökerekben volt szignifikáns.Tenyészedény-kísérleteink alapján kijelenthető, hogy elsősorban az EDTA, illetve részben az EGTA a talajba kijuttatva mobilisabbá, könnyebben felvehetővé teszi az ólmot és a rezet, elősegítve ezzel e két toxikus elem növényekben történő akkumulációját. Szabadföldi körülmények között is feltételezhető, hogy a növények betakarításával a toxikus elemek egy része eltávolítható a szennyezett talajból.

Creation and application of biofertilizers based on the effective consortium destructor microorganisms for remediation of contaminated soils of the Republic of Tatarstan

2017 ◽  
pp. 100-103
Author(s):  
I.A. Degtyareva ◽  
◽  
I.A. Yapparov ◽  
A.Kh. Yapparov ◽  
A.M. Ezhkova ◽  
...  
Keyword(s):  
Contaminated Soils ◽  
The Republic

Methods of oil-contaminated soils diagnostic

2018 ◽  
pp. 106-109
Author(s):  
I.А. Degtyareva ◽  
◽  
I.А. Shaydullina ◽  
А.Ya. Davletshina ◽  
T.Yu. Motina ◽  
...  
Keyword(s):  
Contaminated Soils
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