Recent developments in Korea’s Framework Act on Resource Circulation: toward a resource-circulating society

Korea is moving toward a sustainable resource-circulating society to fight climate change and resource scarcity. To achieve this goal, the Framework Act on Resource Circulation (FRC) was enacted on May 29, 2016 and came into effect on January 1, 2018. This act not only acknowledges the importance of resource efficiency and the transition to a resource-circulating society, but also plays a significant role in the progress of important and relevant market and industry developments. This study primarily focuses on an analysis of the FRC. It aims to evaluate key concepts such as a resource-circulating society, circular resources, important provisions including major principles and allocation of responsibilities, and measures to be taken to promote resource circulation. In addition, it explores whether the FRC is sufficiently comprehensive and ambitious to contribute to the transition to a more resource-circulating society.     

Factors inhibiting bioremediation of soil contaminated with weathered oils and drill cuttings

Oily drill cuttings and a soil contaminated with weathered crude oils were treated by enhanced biodegradation under tropical conditions in industrial scaled experiments. Oil contaminants were characterized by gas chromatography and mass spectrometry. This allowed for the identification of a mixture of two crude oils in the contaminated soil. After 12 months of bioremediation process, the removal of hydrocarbons reached by biodegradation an extent of 60% although nutrient amendment with elevated concentration of N-urea had highly detrimental effects on the hydrocarbon degrading fungal populations due to the production of toxic concentration of ammonia gas by nitrification. The saturated hydrocarbons were extensively assimilated, though n-alkanes were not completely removed. Aromatic hydrocarbons were less degraded than saturated whereas resin and asphaltene fractions were, surprisingly, partly assimilated. In laboratory conditions, the residual hydrocarbons in the field-treated materials were 15-20% further degraded when metabolic byproducts resulting from biodegradation were diluted or removed.     

Humidity- and Age-Tolerant Starch-Based Sponge for Loose-Fill Packaging

Loose-fill packaging sponges were extruded from mixtures of 54–62% hydroxypropylated (HP 5%) amylomaize V (50% amylose) and wheat starches, 17–24% synthetic polymer, 13% water, 7% blowing agent(s), and 0.5% nucleating agent. One product made from 28% HP wheat starch, 28% HP amylomaize V starch, 12% ethylene vinyl alcohol (EVOH) copolymer, 8% polystyrene (PS), and 3% polystyrene maleic anhydride (PSMA) copolymer, plus the other raw materials, had a compressibility and resilience that matched those of expanded polystyrene (EPS), although its bulk density was four times higher. The starchy sponge showed 16% shrinkage in volume at 90% relative humidity and was 2% soluble in excess water, both at 25°C. After aging for 18 months near 25°C, the HP starchy sponge gave only a trace of fines in a simulated shipping test, compared to 20% fines from a biodegradable, starch-based, loose-fill sponge of commerce.     

Echocardiographic diagnosis of fetal marfan syndrome at 34 weeks' gestation

Fetal echocardiography was performed during the third trimester in a normal primigravida. The fetal heart was severely affected with the typical cardiac manifestations of Marfan syndrome. The medical history of the father was investigated and a mild form of the syndrome was diagnosed. The neonate died at 2 months of age of congestive heart failure.     

Microbial reduction of nitrate in the presence of nanoscale zero-valent iron

Microbial reduction of nitrate in the presence of nanoscale zero-valent iron (NZVI) was evaluated to assess the feasibility of employing NZVI in the biological nitrate treatment. Nitrate was completely reduced within 3 d in a nanoscale Fe(0)-cell reactor, while only 50% of the nitrate was abiotically reduced over 7 d at 25 °C. The removal rate of nitrate in the integrated NZVI-cell system was unaffected by the presence of high amounts of sulfate. Efficient removal of nitrate by Fe(II)-supported anaerobic culture in 14 d indicated that Fe(II), which is produced during anaerobic iron corrosion in the Fe(0)-cell system, might act as an electron donor for nitrate. Unlike abiotic reduction, microbial reduction of nitrate was not significantly affected by low temperature conditions. This study demonstrated the potential applicability of employing NZVI iron as a source of electrons for biological nitrate reduction. Use of NZVI for microbial nitrate reduction can obviate the disadvantages associated with traditional biological denitrification, that relies on the use of organic substrates or explosive hydrogen gas, and maintain the advantages offered by nano-particle technology such as higher surface reactivity and functionality in suspensions.     

长江上游和中下游地区空中水汽资源气候特征对比分析

利用ERA 40再分析资料通过多种统计诊断方法对比分析了长江流域上、中下游空中水汽资源的气候变化特征。研究表明：1958～2001年以来长江流域上游以及中下游地区年平均大气可降水量均呈显著减少趋势,减少率分别为025和026 kg/(m2·10 a);年平均状态下,长江流域上中下游地区均为水汽汇,上游地区年平均收入水汽226×105 kg/s,中下游地区收入124×105 kg/s;1958～2001年长江上游地区的年平均总水汽收入呈显著减少趋势,每10 a减少98×105 kg/s;中下游地区则呈显著增加趋势,每10 a增加115×105 kg/s。夏季水汽收入变化是影响长江流域水汽收支的重要因素,44 a来,长江上游地区水汽总收入减少和该区域夏季南边界上输入的水汽减少密切相关;而中下游地区水汽总收入的增加则主要是由夏季北边界上输出的水汽显著减少所导致;1958～2001年长江流域上、中下游地区水汽收支的变化和该时期夏季风北扩强度的变化有密切关系,其携带的南来水汽扩展变化则是最直接的影响因子。     

Anaerobic biotransformation of dinitrotoluene isomers by Lactococcus lactis subsp. lactis strain 27 isolated from earthworm intestine

Dinitrotoluenes are widely used as solvents and are intermediates in the synthesis of dyes, explosives, and pesticides. Environmental concerns regarding DNTs have increased due to their widespread use and their discharge into the environment. In this study, the anaerobic biodegradation of four dinitrotoluene isomers, 2,3-, 2,4-, 2,6- and 3,4-DNT, was investigated using Lactococcus lactis subsp. lactis strain 27, which was isolated from the intestines of earthworms. Liquid chromatography/mass spectrometry and NMR spectroscopy showed that L. lactis strain 27 non-specifically reduced the nitro groups on the tested dinitrotoluenes to their corresponding aminonitrotoluenes. L. lactis strain 27, however, did not reduce either sequentially or simultaneously two nitro groups of the dinitrotoluenes, resulting in the formation of the corresponding diaminotoluenes. In vitro formation of dinitroazoxytoluenes suggested the presence of oxygen-sensitive hydroxylaminonitrotoluenes. L. lactis strain 27 was capable of reducing 2,4-, 2,6-, 2,3-, and 3,4-dinitrotoluenes up to 173.6, 66.6, 287.1, and 355 microM, respectively in 12 h incubation. A relatively rapid reduction was observed in the case of the 2,3-, and 3,4-dinitrotoluenes, which have vicinal nitro groups on their arene structure. Non-specific anaerobic reduction of dinitrotoluenes by the intestinal bacterium L. lactis strain 27 differentiated the extent of reduction of DNTs according to the substitutional position of the nitro groups and produced in vitro more toxic dinitroazoxytoluenes, suggesting that anaerobic biotransformation of dinitrotoluenes could increase environmental risk.     

Phenanthrene degradation in soils co-inoculated with phenanthrene-degrading and biosurfactant-producing bacteria

Contaminant sorption within the soil matrix frequently limits biodegradation. However, contaminant bioavailability can be species-specific. This study investigated bioavailability of phenanthrene (PHE) to two PHE-degrading bacteria (Pseudomonas strain R and isolate P5-2) in the presence of rhamnolipid biosurfactant and/or a biosurfactant-producing bacterium, Pseudomonas aeruginosa ATCC 9027. Pseudomonas strain R mineralized more soil-sorbed PHE than strain P5-2, but in aqueous cultures the rate and extent of PHE mineralization by P5-2 exceeded that by P. strain R. In Fallsington sandy loam (fine-loamy, mixed, active, mesic Typic Endoaquult) (high PHE-sorption capacity) the addition of rhamnolipid increased PHE mineralization by P. strain R. Phenanthrene mineralization in soils inoculated with P5-2 was minimal and no enhancement in PHE degradation was observed when biosurfactant was added. Co-inoculation of Fallsington sandy loam with the biosurfactant producer did not affect PHE mineralization by isolate P5-2, but significantly enhanced PHE mineralization by P. strain R. The enhancement of PHE mineralization could not be explained by P. aeruginosa-mediated PHE degradation. The addition of rhamnolipid at concentrations above the critical micelle concentration (CMC) resulted in enhanced PHE release from test soils. These results suggest that the PHE-degrading strains were able to access different pools of PHE and that the biosurfactant-enhanced release of PHE from soils did not result in enhanced biodegradation. The results also demonstrated that bacteria with the catabolic potential to degrade sorbed hydrophobic contaminants could interact commensally with surfactant-producing strains by an unknown mechanism to hasten the biodegradation of aromatic hydrocarbons. Thus, understanding interactions among microbes may provide opportunities to further enhance biodegradation of soil-bound organic contaminants.     

准噶尔盆地西北缘地层水化学特征与油气关系研究

准噶尔盆地西北缘分为超覆尖灭带、断阶带、斜坡区。本文讨论了不同区带地层水化学特征及其与油气运移聚集的关系。研究结果表明 ,高、过成熟阶段烃源岩生成的轻质油气在其运移聚集过程中 ,伴生的CO2 进入地层水中 ,在一定条件下会形成高矿化度NaHCO3 型地层水 ,而以高矿化度NaHCO3 型地层水为底水的油藏 ,原油密度较轻 ,为轻质原油。在近断层处 ,中、高矿化度的MgCl2 、Ns2 SO4 型地层水 ,可作为油气水沿断裂运移的证据。