Iron- and manganese-porphyrin catalysed aziridination of alkenes by tosyl- and acyl-iminoiodobenzene

In soil science the fraction of colloids in soils is understood as particles with diameters smaller than 2μm. Clay minerals, aquoxides of iron and manganese, humic substances, and other polymeric materials are found in this fraction. The spatial arrangement (microstructure) is controlled by the substantial structure of the colloids, by the chemical composition of the soil solution, and by thesoil biota. This microstructure determines among other things the diffusive mass flow within the soils and as a result the availability of substances for chemical and microbiological reactions. The turnover of nutrients, the adsorption of toxicants and the weathering of soil clay minerals are examples of these surface mediated reactions. Due to their high specific surface area, the soil colloids are the most reactive species in this respect. Under the chemical conditions in soils, these minerals are associated in larger aggregates. The accessibility of reactive sites for these reactions on the surface of the colloids is reduced by this aggregation. To determine the turnover rates of chemicals within these aggregates it is highly desirable to visualize directly these aggregation phenomena.

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The content of copper, zinc, iron and manganese in honey

Annales UMCS Pharmacia ◽

10.2478/v10080-008-0010-4 ◽

2008 ◽

Vol 21 (1) ◽

pp. 77-80

Author(s):

Andrzej Kot ◽

Stanisław Zaręba

Keyword(s):

Copper Zinc ◽

Iron And Manganese

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Iron and Manganese -- Preliminary report on the red iron ores of east Tennessee, northeast Alabama, and northwest Georgia

10.3133/b540g ◽

1914 ◽

Keyword(s):

Preliminary Report ◽

Iron Ores ◽

East Tennessee ◽

Iron And Manganese

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Best Practice Guide on the Control of Iron and Manganese in Water Supply

Water Intelligence Online ◽

10.2166/9781780400747 ◽

2013 ◽

Vol 12 ◽

Cited By ~ 8

Author(s):

Adam Postawa

Keyword(s):

Water Supply ◽

Best Practice ◽

Practice Guide ◽

Iron And Manganese

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Chemical effects on UV irradiation absorption of fouled quartz sleeves in ultraviolet disinfection

Water Science & Technology Water Supply ◽

10.2166/ws.2008.064 ◽

2008 ◽

Vol 8 (2) ◽

pp. 217-222 ◽

Cited By ~ 1

Author(s):

Beibei Zhu Sun ◽

Ernest Blatchley ◽

Mike Oliver ◽

Cheng Zheng ◽

Kristofer Jennings

Keyword(s):

Statistical Analysis ◽

Uv Disinfection ◽

Uv Absorbance ◽

Ultraviolet Disinfection ◽

High Chemical ◽

Chemical Surface ◽

Chemical Effects ◽

Uv Transmittance ◽

Main Effects ◽

Iron And Manganese

The effects of foulant chemical composition on ultraviolet (UV) absorbance of fouled quartz sleeves in UV disinfection systems were studied. Statistical analysis was conducted to examine the effects of nine fouling chemicals on the UV transmittance changes of fouled quartz lamp sleeves. The results demonstrated that the main effects were attributable to surface concentrations of iron and manganese. The surface concentrations of calcium and copper had no significant effects on the UV absorbance of fouled sleeves. The interaction effects of copper with iron and magnesium with manganese were also revealed from the statistical analysis. The model is able to give reasonable predictions of the UV absorbance characteristics of foulants from other UV systems. However, several limitations of this model were identified. First, the model does not accurately predict the absorbance at relatively high chemical surface concentrations. Second, the model does not account for the possible effects of anions and organics on UV absorption of fouled quartz sleeves.

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Investigation into Mechanisms of Microbial Effects on Iron and Manganese Transformations in Artificially Recharged Groundwater

Water Science & Technology ◽

10.2166/wst.1988.0080 ◽

1988 ◽

Vol 20 (3) ◽

pp. 47-53 ◽

Cited By ~ 1

Author(s):

Yan Bao-rui

Keyword(s):

Groundwater Quality ◽

Biochemical Reaction ◽

Reaction Products ◽

Injection Wells ◽

Iron Bacteria ◽

Sulphate Reducing Bacteria ◽

Prevention And Treatment ◽

Reducing Bacteria ◽

Iron And Manganese ◽

Microbial Effects

After artificial recharging of groundwater some problems occurred, such as changes in groundwater quality, the silting up of recharge (injection) wells, etc. Therefore, the mechanisms of microbial effects on groundwater quality after artificial recharging were studied in Shanghai and the district of Changzhou. These problems were approached on the basis of the amounts of biochemical reaction products generated by the metabolism of iron bacteria, sulphate-reducing bacteria, Thiobacillusthioparus, and Thiobacillusdenitrificans. The experiments showed that in the transformations occurring and the siltation of recharge wells, microorganisms play an important role, due to the various chemical and biochemical activities. A water-rock-microorganisms system is proposed, and some methods for the prevention and treatment of these effects are given.

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