Effect Of Organic Materials Research Articles

Effect of Organic Materials on Partitioning, Extractability and Plant Uptake of Metals in an Alum Shale Soil

Soils developed on sulphide-bearing shale (alum shale) in Norway contain naturally high amount of heavy metals. We conducted a greenhouse pot experiment to study the effect of four rates (0, 2, 4, and 8%) and three sources (cow manure, pig manure and peat soil) of organic matter in partitioning and distribution, extractability and plant uptake of Cd, Cu, Ni and Zn in an alum shale soil. Sequential extraction scheme was used to determine the distribution patterns of metals in the soil. DTPA was used for extracting the metals from the soil. Wheat (Triticum aestivum) was used as a test crop to study the plant uptake of metals. The highest amount of Cd was present in the exchangeable fraction, irrespective of the rate and source of organic matter applied. Copper, Ni, and Zn, on the other hand, were present only in small quantities in this fraction. The largest fraction of Cu was associated with organic matter and the amounts present in the oxide, carbonate and exchangeable fractions were very small. Nickel and Zn were found mainly in the residual fraction. Increasing rates of cow and pig manure decreased the amounts of Cd and Ni associated with the exchangeable fraction whereas, the addition of peat soil at the same rate increased the amounts of these metals associated with this fraction. This effect of organic matter was primarily associated with the change in soil pH caused by different organic matter sources. The DTPA-extractable metals were decreased with increasing rates of organic matter application, irrespective of its source. Grain and straw yields of wheat were decreased with increasing rates of organic matter. The application of organic matter increased the Cu and Zn concentrations in both grain and straw. The concentration of all metals was lower in plants grown in the cow manure amended soil as compared to those grown in the soil amended with either pig manure or peat soil. These results sugggest that the source of organic matter was a determining factor for metal distribution in the soil and for metal uptake by plants. In this study cow manure slightly increased the soil pH and thus was more effective than either pig manure or peat soil in reducing the plant uptake of metals but in general the efficiency of the organic material in reducing heavy metal uptake was small.

Microstructural analysis of OPC/silica fume/Na‐bentonite interactions in cement based solidification of organic‐contaminated hazardous waste

As one of major deficiencies in cement‐based waste stabilization/solidification (S/S) processes is their difficulty in treating inorganic wastes containing organic material, silica‐fume and Na‐bentonite are studied as potential pozzolanic reagent and pre‐solidification adsorbent of organic components. This paper presents microstructural studies of interactions between silica fume, Na‐bentonite, containing adsorbed organically contaminated harzardous wastes, and a cement matrix. The scanning electron microscopy/ energy dispersive spectroscopy (SEM/EDS) analysis of the waste/OPC mix showed that the ettringite crystals were in needle shape deposited in the voids or on the surface of hydration material. Microstructural studies of solidified wastes with silica fume and/or Na‐bentonite showed that their presence caused an inhibition to the ettringite formation. The results indicated that the incorporation of silica fume and/or Na‐bentonite into the cement matrix minimized the detrimental effects of organic materials on the cement hydration reaction.

PHREEQEV: The incorporation of a version of Model V for organic complexation in aqueous solutions into the speciation code phreeqe

Organic-inorganic phase interactions and the effect of organic material in solution on the transport properties of metal contaminants are of considerable interest to the waste disposal industry. However, the inclusion of organic material in inorganic aqueous speciation calculations is problematic because large organic molecules, such as fulvic and humic acids, contain a large number and range of potential binding sites, and it is difficult to define discrete equilibrium constants for each binding reaction that is taking place. In addition, any such equilibrium constant defined will differ with factors such as the electrostatic charge related to the degree of dissociation of the molecule and interference between sites. Modern approaches for modeling such organic molecules generally are combinations of either a discrete ligand or continuous distribution representation of the binding sites combined with electrostatic theory. A sophisticated, discrete-site electrostatic organic binding model, Model V, developed by Tipping and coworkers at the Institute of Freshwater Ecology (IFE) at Windermere, UK, has been implemented into the established inorganic speciation code, PHREEQE. The cross-verification of the new code, PHREEQEV, with a code developed independently at IFE is presented.

Nitrogen removal from wastewaters by a bio-reactor with partially and fully submerged rotating biofilms

This paper concerns simultaneous nitrification and denitrification in a completely mixed bio-reactor with partially and fully submerged rotating biological contactors. The bio-reactor is designed to cause the nitrification and denitrification in partially and fully submerged biofilms, respectively. An experimental investigation was made into the effect of organic material and ratio of influent organic carbon to ammonia nitrogen concentrations(C/N ratio) on the efficiency of simultaneous nitrification and denitrification in the bio-reactor. Settled municipal wastewater and synthetic wastewater containing ammonia nitrogen and organic material such as acetate, ethylene-glycol, phenol and poly-vinyl-alcohol(PVA) were fed into the experimental units. A biofilm dominated by nitrifiers developed on the partially submerged contactors, while a biofilm dominated by heterotrophs developed on the fully submerged contactors. A micro-aerobic environment was formed and biological denitrification occurred in the submerged biofilm. In the municipal wastewater treatment where the influent C/N ratio was around 3.5, the maximum nitrogen removal efficiency was about 60 %. Acetate and ethlene-glycol were effectively used as the organic source of the denitrification. The ability to aerobically degrade PVA was induced by phenol. Once the bacteria inhibiting the biofilm gained the ability to degrade PVA, PVA became an effective organic source of the denitrification.

Design and Evaluation of Organic Nonlinear Optical Materials with a Large Pockels Effect

Abstract This paper reviews a method of examining the Pockels effect in small and thin flakes of organic material, and discusses the possibility of further improving the Pockels effect in organic materials in terms of the molecular orbital method. The electro-optic coefficient r33 of the styrylpyridinium cyanine dye (SPCD) crystal was estimated from the AC modulation method to be about 430 pm/V at a wavelength λ of 633 nm, 6 times larger than the r11 of 2-methyl-4-nitroaniline (MNA). To improve the Pockels effect further, artificial molecules with a polydiacetylene structure were designed. By adjusting conjugated lengths and donor- and acceptor-substitution sites in the molecules, a large second-order hyperpolarizability was obtained, corresponding to an electro-optic coefficient about 10 times larger than r11 of MNA at a detuning energy of 0.2 eV.

The effect of organic materials and their humified fractions on the formation and stabilization of soil aggregates

The effect of various organic materials on soil aggregation has been studied on a clay soil, and the results obtained were compared with those from a sandy-loam soil. The soil samples were incubated with two different rates of organic materials from peat or manure during periods of 2 and 17 weeks. It was observed that the original materials did not produce a favourable effect on the formation of new aggregates or on their stability, and the soil became unstabilized with time as a consequence of their application. The humic+fulviv acid fraction was the most efficient one, and the relative increase in the stability was four times greater in a sandy-loam than in a clay soil.

The influences of organic residues on utilization of urea N by rice

The organic materials of vetch straw, isotopically labeled with15N and unlabeled, rice straw and15N-enriched urea were applied to rice in a greenhouse experiment to evaluate the release of available N during the decomposition of vetch material and its uptake by rice, and to measure the effect of organic materials on the efficiency of urea-N utilization by rice. Measurements were made at three sampling stages during the growth period. As expected, vetch material decomposed readily and furnished a continuous supply of N for the growth of rice, although only 18.1% of vetch-N was utilized by the rice crop. However, this was not sufficient to support the survival of all tillers until harvest. After harvest, 70% of vetch-N still remained in paddy soil. The influence of organic materials on urea-N absorption by rice became apparent at about the stage of panicle initiation. The highest urea-N uptake by rice was 42.2% in vetch straw-mixed soil. Otherwise, rice straw retarded urea-N uptake by rice. Nitrogen distribution data indicated that the vetch material would stimulate urea-N uptake by rice plants.

Review of stopping powers in organic materials

A survey of tests concerning Bragg's rule of stopping power additivity is updated, summarising recent evidence on chemical binding and physical state effects on stopping power in organic and related materials. A general failure of simple additivity is well-established, but magnitudes of effects are still subject to uncertainty. Phase effects in organic materials are ~ 5–10% at stopping power maximum for H and He ions, decreasing as energy increases. The stopping cross-sections of gases are greater than those of the equivalent condensed phase. Accuracy of stopping power measurements in organic compounds is often insufficient to unambiguously detect and quantify such effects. However sensitive tests of additivity can be obtained where uniform series of measurements have been carried out by one group with one method in a range of materials.

底泥中の銅の再溶出に及ぼす水中有機物の影響の銅（ＩＩ）錯化容量による推定

底泥中の銅の再溶出に及ぼす水中有機物の影響の銅（ＩＩ）錯化容量による推定

Ion bombardment effects in polymers

Abstract Ion bombardment of organic materials produces dramatic changes in their properties associated with disruption and rearrangement of the original chemical bonding and formation of new molecular products. In polymers, bombardment results in cross linking and/or chain scission, gas evolution and eventual carbonization. In films of relatively non-volatile organic molecules ion bombardment can result in polymerization or in decomposition with metallic residue film formation. Intense laser radiation in polymers can lead to material ablation through explosive ejection processes. Similar explosive effects are implied by the results of ion beam irradiation of nitrocellulose. The status of the field of ion bombardment effects in organic materials is still in its infancy from the point of view of detailed understanding of the mechanisms involved. This article is a brief review of the diversity of effects being studied.

The effect of organic materials and solids in water on the persistence of Bacillus thuringiensis var. israelensis Serotype H‐141

AbstractSome factors which inactivate Bacillus thuringiensis var. israelensis (B.t.i.) in the water were investigated. Efficacy of B.t.i. against 2nd stage larvae of Culex pipiens and of Aedes aegypti decreased when organic matter was present in the water, or when sterilised silt was added as compared to nonsterilised one. Sludge from Loess soil decreased the efficacy of B.t.i. more than did decomposing organic matter, or inorganic mud, or silica gel, respectively. The smaller the silt particle, the greater was the decrease in B.t.i. efficacy. LC100 concentration of B.t.i. lost 50% of its larvicidal activity after 6 days, whereas 100 × LC100 remained effective for about 11 days.ZusammenfassungZur Wirkung organischer Materialien und Lösungen in Wasser auf die Wirkung von Bacillus thuringiensis var. israelensis, Serotype H‐14Einige Faktoren, die B.t.i. im Wasser inaktivieren, wurden untersucht. Die Wirksamkeit von B.t.i. gegen die L2 von Culex pipiens und Aedes aegypti sank, wenn organisches Material im Wasser vorhanden war oder wenn sterilisierter Schlamm im Vergleich zu unsterilisiertem hinzugefügt wurde. Schlamm aus Lößboden verringerte die Wirkung von B.t.i. stärker als dies in Zersetzung befindliches organisches Material ‐ oder anorganischer Schlamm ‐ oder Kieselgel taten. Je kleiner die Schlammpartikel waren, desto größer war die Abnahme der Bacillus‐Wirkung. Bei der LC100‐Konzentration verlor B.t.i. 50% seiner larvaziden Wirkung nach 6 Tagen, bei einer Konzentration von 100 × LC100 nach 11 Tagen.

Incorporation of fluoride ions into calcite. Effect of organic materials and magnesium ions in a parent solution.

The effect of citrate, malate, lactate and acetate ions in a parent solution on the incorporation of fluoride ions into formed calcite has been studied experimentally. Citrate ions in a parent solution containing no magnesium ions increase intensively the amount of fluoride ions incorporated into magnesium-free calcite, and malate ions do so but moderately, while lactate and acetate ions have little effect on the incorporation of fluoride ions into calcite. The amount of fluoride ions incorporated into low Mg-calcite (smaller than 4% magnesium carbonate) formed from a parent solution containing magnesium ions but no citrate ions remarkably increases with increasing magnesium carbonate content of the formed low Mg-calcite. This trend is in agreement with that observed in marine calcareous skeletons (OHDE and KITANO, 1980). The amount of fluoride ions incorporated into high Mg-calcite formed from a parent solution containing both magnesium and citrate ions is large. The fluoride amount slightly increases with increasing magnesium carbonate content of the formed high Mg-calcite.

The effect of organic material and inorganic ions on the photosynthetic rate of the red alga Bostrychia binderi from a Florida estuary

Various constituents of spring water (calcium, bicarbonate, nitrate, phosphate, total organic material) influence the response of photosynthetic rate of Bostrychia binderi Harvey to changes in salinity. The rate of photosynthesis increased with a decrease in salinity. The rate of photosynthesis in low salinities was greater in seawater diluted with spring water than in sewater diluted with distilled water. Elevation of photosynthetic rates in the lower salinities (0 and 5 ppt) was partially due to increased levels of bicarbonate and various nutrients present in natural spring water. The higher calcium levels in spring water resulted in higher photosynthetic rates in plants held for 3 to 7 d in the lower salinities (0 to 5 ppt). Increased levels of calcium in salinities of 5 ppt or higher increased the photosynthetic rate only during the first 7 d of exposure, since acclimation occurred equally in individuals held for 2 to 8 wk in sewater diluted with distilled or spring water. This study suggests that the diverse algal floras, characteristic of estuaries on the west coast of Florida are in part the result of natural spring water mixing with seawater, sustaining the algae over short periods of low salinities.

都市域における大気中のエアロゾル粒子の凝結核としての不活性度

In order to make clear how much extent urban aerosol particles are inactivated as con-densation nuclei, possibly by the effect of organic materials, an experimental study was made using a vertical thermal diffusion chamber and an impactor. Inactive particles, which grew slowly or not at all under the supersaturation less than about 1%, were collected separated from active particles, and the concentration of inactive particles was compared with that of atmospheric aerosol particles by means of a transmission electron microscope. It was found that inactive particles scarcely existed. This result indicates that most of the atmospheric aerosol particles are not greatly inactivated as condensation nuclei even in the possible pres-ence of organic materials in the urban area.

Selective flame emission detection of phosphorus and sulfur in high-performance liquid chromatography

A selective detector for phosphorus and sulfur based on flame emission has been developed for use with high-performance liquid chromatography. Up to 5 ml/min of the total column effluent is nebulized and directed into a cool hydrogen-nitrogen flame. In this flame, phosphorus- and sulfur-containing compounds emit characteristic emissions at 526 and 383 nm, respectively, which are measured by a simple band-pass filter/photomultiplier system. In favorable situations, the apparatus permits the detection of about 2 · 10 −8 and 2 · 10 −7 g/ml of phosphorus and sulfur, respectively, in the column effluent. However, with optimization of the system, sensitivity may be increased by an order of magnitude. The flame emission detector can be used for compounds containing phosphorus and sulfur in different forms. Excellent short- and long-term quantitation has been experienced in trace analysis. To date, application of the detector has been limited to systems with aqueous mobile phases since significant concentrations of organic materials affect detector sensitivity. Factors influencing the signal-to-noise response of the detector have been studied. These include: mobile phase nebulization rate, hydrogen, nitrogen and air flow-rates, and the effect of organic materials and salts.

Observations on the effect of organic materila upon aggregation and nitrate-nitrogen content of soil

In the experiments reported above the effect of organic material upon the aggregation of soil particles and the simultaneous immobilization of mineral nitrogen by microorganisms were studied. The relative amount of water-stable aggregates larger than 0.5 mm in diameter was considered to indicate the aggregation state of the soil samples. Probably, somewhat different results were obtained if the crumb formation had been determined by some other method, but it is not sure that these would have been more reliable. Since the incubation of soil samples were performed under aerobic conditions, and all the samples were mineral soils, it seemed justifiable to take the nitrate-nitrogen content of the soil samples to characterize the amount of mineral nitrogen in them. On the basis of the results the general conclusion may be drawn that the more favourable the conditions are for the development of an active and large microflora in the soil, the more intensively the crumb formation and the immobilization of nitrogen takes place, but also the destruction of aggregates begins the more rapidlv. This appeared to be true with regard to the indigenous fertility of soil as well as to the fertilization. Liming, however, did not improve the conditions in these experiment, probably due to the rather slight acidity of the soil samples used. Under otherwise similar conditions the larger amount of straw produced larger amount of aggregates, but the differences in the nitrate-nitrogen content of soil in the presence of various amounts of straw were neglibigle. Generally, the degree of immobilization of soil nitrogen seemed largely to depend on the properties of soil and on other environmental conditions, and nitrogen applications, theoretically enough for the needs of microorganisms that decomposed the straw, could not always prevent an intensive absorption of soil nitrogen. The crumb formation appeared to need mere energy-yielding material than the immobilization of nitrogen, or the destruction of crumbs occurred more rapidly than the nitrification of microbiologically bound nitrogen.