Concerns regard watering crops with Hg contaminated waters have arisen worldwide recently. In these sense Hg uptake by Vitis vinifera L. cv. Malbec was evaluated under greenhouse conditions by the administration of Hg2+ for 4 days through irrigation water (short term administration). Vines uptake Hg translocating it from roots through stems to leaves. Roots accumulated the higher Hg concentration. Hg in stems and leaves was accumulated mostly as organic Hg, bind to different moieties. Size Exclusion Chromatography (SEC) and Ion Pair Chromatography (IPC) were employed to reach insights into these ligands. Hg is distributed mainly in high molecular weight fractions of 669 kDa in vine plants. In stems and leaves, Hg-S associations were found in 669 and 66 kDa fractions. Hg-S association at 66 kDa suggests a possible protein or peptide binding affecting vines normal physiology. Since Hg contamination through organomercurials is more harmful than Hg2+ itself, methyl mercury, dimethyl mercury and phenyl mercury, more toxic Hg species were evaluated with negative results.

Elsholtzia splendens is a copper-tolerant plant species growing on copper deposits in China. Spatially and spectrally resolved kinetics of in vivo absorbance and chlorophyll fluorescence in mesophyll of E. splendens were used to investigate the copper-induced stress from deficiency and toxicity as well as the acclimation to excess copper stress. The plants were cultivated in nutrient solutions containing either Fe(III)-EDTA or Fe(III)-EDDHA. Copper toxicity affected light-acclimated electron flow much stronger than non-photochemical quenching (NPQ) or dark-acclimated photochemical efficiency of PSIIRC (Fv/Fm). It also changed spectrally resolved Chl fluorescence kinetics, in particular by strengthening the short-wavelength (<700 nm) part of NPQ altering light harvesting complex II (LHCII) aggregation. Copper toxicity reduced iron accumulation, decreased Chls and carotenoids in leaves. During acclimation to copper toxicity, leaf copper decreased but leaf iron increased, with photosynthetic activity and pigments recovering to normal levels. Copper tolerance in E. splendens was inducible; acclimation seems be related to homeostasis of copper and iron in E. splendens. Copper deficiency appeared at 10 mg copper per kg leaf DW, leading to reduced growth and decreased photosynthetic parameters (F0, Fv/Fm, ΦPSII). The importance of these results for evaluating responses of phytoremediation plants to stress in their environment is discussed.

We consider the vulnerability of nuclear power plants to a disaster like the one that occurred at Fukushima Daiichi. Examination of Japanese nuclear plants affected by the earthquake and tsunami on March 11, 2011 shows that three variables were crucial at the early stages of the crisis: plant elevation, sea wall elevation, and location and status of backup generators. Higher elevations for these variables, or waterproof protection of backup generators, could have mitigated or prevented the disaster. We collected information on these variables, along with historical data on run-up heights, for 89 coastal nuclear power plants in the world. The data shows that: 1. Japanese plants were relatively unprotected against potential inundation in international comparison, but there was considerable variation for power plants within and outside of Japan; 2. Older power plants and plants owned by the largest utility companies appear to have been particularly unprotected.

Metal oxides such as ferric or aluminum oxides can play an important role in the retention of bacteria in granular aquatic environments; however, their role in bacterial inactivation is not well understood. Herein, we examined the role of water chemistry and surface chemistry on the short-term inactivation rates of three bacteria when adhered to surfaces. To evaluate the role of water chemistry on the inactivation of attached bacteria, the loss in membrane integrity of bacteria attached to an iron oxide (Fe2O3) surface was measured over a range of water ionic strengths of either monovalent or divalent salts in the absence of a growth substrate. The influence of surface chemistry on the inactivation of attached bacteria was examined by measuring the loss in membrane integrity of cells attached to three surfaces (SiO2, Fe2O3, and Al2O3) at a specific water chemistry (10 mM KCl). Bacteria were allowed to attach onto the SiO2 or metal oxide coated slides mounted in a parallel-plate flow cell, and their inactivation rate (loss in membrane integrity) was measured directly without removing the cells from the surface and without disturbing the system. X-ray photoelectron spectroscopy analysis revealed a high correlation between the amounts of C-metal or O-metal bonds and the corresponding bacterial inactivation rates for each surface. Finally, for all three surfaces, a consistent increase in inactivation rate was observed with the type of bacterium in the order: Enterococcus faecalis, Escherichia coli O157:H7, and Escherichia coli D21f2.

The advantage of circulating fluidized bed (CFB) boiler in China is the utilization of low rank coal with low cost emission control. However, the new National Emission Regulation (NER) issued in early 2012 brings much more stringent challenges on the CFB industries, which also causes much attention from other countries. Based on the principle of a CFB boiler and the previous operating experiences, it is possible for the CFB boilers to meet the new NER and maintain the advantage in low cost emission control, while, more influences should be considered in the design and operation of a CFB boiler. In order to meet the requirement of the new NER, the fly ash collector should adopt the bag house or combination of electrostatic precipitator and bag filter to ensure the dust emission of less than 30mg/Nm3. For the SO2 emission control, the bed temperature should be strictly lower than 900 oC to maintain high reactivity and pores. The limestone particle size distribution should be ranged within a special scope to optimize the residence time and gas-solid reaction. At the same time, the injecting point should be optimized to ensure fast contact of lime with oxygen. In such conditions, the desulphurization efficiency could be increased more than 90%. For lower sulphur content fuels (<1.5%, referred value based on the heating value of standard coal of China), increasing Ca/S enough could decrease SO2 emission lower than that of the new NER, 100mg/Nm3,while, for fuels with sulphur content higher than 1.5%, some simplified systems for flue gas desulphurization, such as flash dryer absorber (FDA), are needed necessarily. And the NOx emission of a CFB can be controlled less than 100mg/Nm3 without any equipment at the bed temperature lower than 900oC for fuels with low volatile (<12%), while for the fuels with high volatile, the Selective Non-Catalytic Reduction (SNCR) should be considered. Due to the unique temperature in CFB as well as the circulating ash, the efficiency of SNCR could reach as high as 70%. The Hg emission of CFB is very low for the new NER due to its innate property.

The destruction of ethylene in a dielectric barrier discharge plasma is investigated by the combination of kinetic modeling and experiments, as a case study for plasma-based gas purification. The influence of the specific energy deposition on the removal efficiency and the selectivity towards CO and CO2 is studied for different concentrations of ethylene. The model allows to identify the destruction pathway in dry and humid air. The latter is found to be mainly initiated by metastable N2 molecules, but the further destruction steps are dominated by O atoms and OH radicals. At increasing air humidity the removal efficiency drops by ±15% (from 85% to 70%), but the selectivity towards CO and CO2 stays more or less constant at 60% and 22%, respectively. Beside CO and CO2, we also identified acetylene, formaldehyde and water as by-products of the destruction process, with concentrations of 1606 ppm, 15033 ppm and 185 ppm in humid air (with 20% RH), respectively. Finally, we investigated the by-products generated by the humid air discharge itself, which are the greenhouse gases O3, N2O and the toxic gas NO2.

Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) have received high concerns due to their extreme persistence, and very few technologies have been reported for their complete destruction. For sound PFCs wastes disposal, mechanochemical method was employed using a planetary ball mill. Potassium hydroxide (KOH) was identified as the best co-milling reagents and nearly complete destruction of both PFOS and PFOA was realized. The measured water soluble fluoride accounted for most of the organic fluorine. The final products of PFOS after treatment were shown to be KF and K2SO4 by XRD analysis. The mass ratio between PFOS and KOH significantly affected the fluoride recovery, but not for PFOS destruction and the sulfate recovery. The gradual formation of sulfate and fluoride reveals that the degradation of PFOS is initiated with the dissociation of the sulfonate group. FTIR spectra further showed the disappearance of the -CF3 and -CF2- groups with the generation of sulfate. The cleavage of C-F bonds in PFOS and the formation of fluoride ion were also identified by XPS spectra. Based on these results, possible reaction pathways were proposed. The approach was also successfully applied for the destruction of PFOS and PFOA homologues with different chain length.

Our line of papers revealed that the common (great) cormorant (Phalacrocorax carbo) possesses two isoforms of the aryl hydrocarbon receptor (ccAHR1 and ccAHR2). This paper addresses in vitro tests of the ccAHR signaling pathways to solve two questions; 1) whether there are functional differences in the two ccAHR isoforms and 2) whether a molecular perturbation, cytochrome P450 1A (ccCYP1A) induction, in the population-level can be predicted from the in vitro tests. The transactivation potencies mediated by ccAHR1 and ccAHR2 were measured in COS-7 cells treated with 15 selected dioxins and related compounds (DRCs), where ccAHR1 or ccAHR2 expression plasmid and ccCYP1A5 promoter/enhancer-linked luciferase reporter plasmid were transfected. For congeners that exhibited dose-dependent luciferase activities, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) relative potencies (REPs) and induction equivalency factors (IEFs) were estimated. ccAHR1-IEF profile was similar to WHO avian TCDD toxic equivalency factor (TEF) profile except for dioxin-like polychlorinated biphenyls that showed lower IEFs in ccAHR1-driven reporter assay. ccAHR2-IEF profile was different from WHO TEFs and ccAHR1-IEFs. Notably, 2,3,4,7,8-PeCDF was more potent than TCDD for ccAHR2-mediated response. Using ccAHR1- and ccAHR2-IEFs and hepatic DRC concentrations in the Lake Biwa cormorant population, total TCDD induction equivalents (IEQs) were calculated for each ccAHR-mediated response. Non-linear regression analyses provided significant sigmoidal relationships of ccAHR1- and ccAHR2-derived IEQs with hepatic ccCYP1A5 mRNA levels, supporting the results of in vitro ccAHR-mediated TCDD dose-response curves. Collectively, our in vitro AHR reporter assay could potentially be an alternative to molecular epidemiology of the species of concern regarding CYP1A induction by AHR ligands.

Microbial electrosynthesis is the biocathode-driven production of chemicals from CO2 and has the promise to be a sustainable, carbon-consuming technology. To date, microbial electrosynthesis of acetate, the first step in order to generate liquid fuels from CO2, has been characterized by low rates and yields. To improve performance, a previously established acetogenic biocathode was operated in semi-batch mode at a poised potential of -590 mV vs SHE for over 150 days beyond its initial development. Rates of acetate production reached a maximum of 17.25 mM day(-1) (1.04 g L(-1) d(-1)) with accumulation to 175 mM (10.5 g L(-1)) over 20 days. Hydrogen was also produced at high rates by the biocathode, reaching 100 mM d(-1) (0.2 g L(-1) d(-1)) and a total accumulation of 1164 mM (2.4 g L(-1)) over 20 days. Phylogenetic analysis of the active electrosynthetic microbiome revealed a similar community structure to what was observed during an earlier stage of development of the electroacetogenic microbiome. Acetobacterium spp. dominated the active microbial population on the cathodes. Also prevalent were Sulfurospirillum spp. and an unclassified Rhodobacteraceae. Taken together, these results demonstrate the stability, resilience, and improved performance of electrosynthetic biocathodes following long-term operation. Furthermore, sustained product formation at faster rates by a carbon-capturing microbiome is a key milestone addressed in this study that advances microbial electrosynthesis systems toward commercialization.

Subsurface transport of plutonium (Pu) may be facilitated by the formation of intrinsic Pu colloids. While this colloid-facilitated transport is largely governed by the electrokinetic properties and dispersion stability (resistance to aggregation) of the colloids, reported experimental data is scarce. Here, we quantify the dependence of ζ-potential of intrinsic Pu(IV) colloids on pH and their aggregation rate on ionic strength. Results indicate an isoelectric point of pH 8.6 and a critical coagulation concentration of 0.1 M of 1:1 electrolyte at pH 11.4. The ζ-potential/pH dependence of the Pu(IV) colloids is similar to that of goethite and hematite colloids. Colloid interaction energy calculations using these values reveal an effective Hamaker constant of the intrinsic Pu(IV) colloids in water of 1.85 × 10(-19) J, corresponding to a relative permittivity of 6.21 and refractive index of 2.33, in agreement with first principles calculations. This relatively high Hamaker constant combined with the positive charge of Pu(IV) colloids under typical groundwater aquifer conditions led to two contradicting hypotheses: (a) the Pu(IV) colloids will exhibit significant aggregation and deposition, leading to a negligible subsurface transport or (b) the Pu(IV) colloids will associate with the relatively stable native groundwater colloids, leading to a considerable subsurface transport. Packed column transport experiments supported the second hypothesis.