[en] The problem of the origin of organic matter in carbonic chondrites is discussed. It is noted that organic matter of carbonic chondrites is the product of nonbiological processes of organic synthesis in space.It is supposed that all the matter of carbonic chondrites should be considered as a complex of various initial formations of a photoplanetary cloud

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[en] Highlights: • The benthic community was affected by the growth and decline of Bo. proboscidea populations. • The boom-bust of Bo. proboscidea invasion was mediated by sewage. • In the boom of Bo. proboscidea was observed the species loss. • Bo. proboscidea and Br. rodriguezii coexist when decreased Bo. proboscidea population. • Community parameters decrease during the boom phase of Bo. proboscidea invasion. Biological invasions produce an invader population boom but are often followed by an invader population bust. The decrease of the invader abundance ends with the coexistence of native species and the invader or with repeated boom and bust events. In the southwest Atlantic, the polychaete Boccardia proboscidea invaded the coasts influenced by sewage discharge. We studied the change in the intertidal benthic community during the boom-bust dynamic of the Bo. proboscidea invasion. During the boom, the invader polychaete was dominant forming monoculture reefs. Species richness, diversity, and evenness indices decrease in the boom phase. During the bust of the Bo.proboscidea invasion, the decrease of organic matter allowed Br. rodriguezii to coexist with Bo. proboscidea. Beta diversity comparing boom with the bust phase showed a greater nesting (nestedness component); reflecting a process of species loss. We found that both boom and bust phases of the polychaete Bo. proboscidea invasion were mediated by sewage.

[en] We have developed a method for quantitative luminescent analysis of multicomponent media. To carry out this method, we need to use a standard luminescent probe and have overlap between the luminescence excitation spectra of the probe and the analyte substance. We have shown that the method is applicable for analysis of scattering media with different absorption optical densities, including optically dense media. We have demonstrated that it is invariant relative to changes in the experimental geometry and the parameters of the medium. A broad range of measurable values is characteristic of the method. Its sensitivity is determined by the sensitivity of the luminescence intensity measurements. We have determined concentrations of organic substances in the range ∼10-10 to 10-11 g/cm³. (authors)

[en] The present state of knowledge of the significance, with respect to dose, or organically-bound tritium (OBT) in diet items has been reviewed. Ratios of the specific activity of the OBT to that of the free water (HTO) in foodstuffs have been commonly reported in the range of 1 to 4. A metabolism model of Etnier, Travis and Hetrick that takes direct assimilation of food OBT into account indicates that such levels result in a dose two to three times greater than that calculated solely on the basis of body water tritium content. Very high OBT/HTO values reported by Italian studies on food items are discounted. It is recommended that OBT/HTO measurements be done on Canadian diet items and that tritium metabolism models be more thoroughly evaluated. 71 refs

[en] Dried, sized, and homogenized peat that contained 5980 ± 307 ppm U was subjected to a variety of leaching conditions to determine the nature and strength of U-organic bonding in recently accumulated organic matter. The fraction of U leached in 24 h experiments at 25⁰C ranged from 0 to 95%. The most effective leach solutions included H₂SO₄ and concentrated (>0.01 M) solutions of sodium bicarbonate-carbonate, or sodium pyrophosphate. Effective leaching by carbonate and pyrophosphate in the absence of added oxidant, and the insignificant effect of added oxidant (as pressurized O₂) strongly suggest that U is initially fixed on organic matter as an oxidized U(VI) species. Uranium is more strongly bound than some other polyvalent cations, based on its resistance to exchange in the presence of large excesses of dissolved Ca²⁺ and Cu²⁺. Measurements of the rate of U leaching indicate faster rates in acid solution compared to carbonate solution, and are consistent with simultaneous attack of sites with different affinities for U. Sulfuric acid appears a good choice for commercial extraction of U from mined peat. In situ disturbances such as overliming of peat soils, addition of fertilizers containing pyrophosphate, or incursions of natural carbonate-rich waters could produce significant remobilization of U, and possibly compromise the quality of local domestic water supplies. (author)

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[en] Nonylphenol (NP), ubiquitously detected as the degradation product of nonionic surfactants nonylphenol polyethoxylates, has been reported as an endocrine disrupter. However, most pure microorganisms can degrade only limited species of NP with low degradation efficiencies. To establish a microbial consortium that can effectively degrade different forms of NP, in this study, we isolated a facultative microbial consortium NP-M2 and characterized the biodegradation of NP by it. NP-M2 could degrade 75.61% and 89.75% of 1000 mg/L NP within 48 h and 8 days, respectively; an efficiency higher than that of any other consortium or pure microorganism reported so far. The addition of yeast extract promoted the biodegradation more significantly than that of glucose. Moreover, surface-active compounds secreted into the extracellular environment were hypothesized to promote high-efficiency metabolism of NP. The detoxification of NP by this consortium was determined. The degradation pathway was hypothesized to be initiated by oxidization of the benzene ring, followed by step-wise side-chain biodegradation. The bacterial composition of NP-M2 was determined using 16S rDNA library, and the consortium was found to mainly comprise members of the Sphingomonas, Pseudomonas, Alicycliphilus, and Acidovorax genera, with the former two accounting for 86.86% of the consortium. The high degradation efficiency of NP-M2 indicated that it could be a promising candidate for NP bioremediation in situ. - Highlights: • Consortium NP-M2 could degrade and detoxify nonylphenol effectively. • The addition of organic matter promoted biodegradation. • Secreted surface-active compounds might facilitate biodegradation. • The degradation pathway for NP by NP-M2 was proposed. • Bacterial composition was analyzed using the 16S rDNA library. - Isolation and characterization analysis of an efficient nonylphenol-degrading bacterial consortium with an efficiency higher than that of other reported microorganisms.

No abstract available

[en] Highlights: ► Increases in acidity, washing frequency, and operational temperature enhance the Cd removal. ► Approximately 80% of Cd can be removed from the soil by dissolved organic matter (DOM) washing. ► The DOM washing can moderate the loss of soil fertility. ► The DOM washing will have a great improvement if we employ NaOH, KOH, Ca(OH)₂, and Mg(OH)₂ to prepare the DOM solution together. -- Abstract: Soil washing using an acid solution is a common practice for removing heavy metals from contaminated soil in Taiwan. However, serious loss of nutrients from soil is a major drawback of the washing. Distillery sludge can be used to prepare a dissolved organic matter (DOM) solution by extracting its organic constituents with alkaline solutions. This study employed DOM solutions to remediate Cd-contaminated soil (with concentrations up to 21.5 mg kg⁻¹) and determine the factors affecting removal of Cd, such as pH, initial concentration of DOM solution, temperature, and washing frequency. When washing with pH 3.0 and 1250 mg L⁻¹ DOM solution, about 80% and 81% of Cd were removed from the topsoil at 27 °C and subsoil at 40 °C, respectively. To summarize the changes in fertility during DOM washing with various pH solutions: the increase in organic matter content ranged from 7.7% to 23.7%; cation exchange capacity (CEC) ranged from 4.6% to 13.9%; available ammonium (N-NH₄) content ranged from 39.4% to 2175%; and available phosphorus content ranged from 34.5% to 182%. Exchangeable K, Ca, and Mg remained in the topsoil after DOM washing, with concentrations of 1.1, 2.4, and 1.5 times higher than those treated with HCl solution at the same pH, respectively