Lindhardtrohde1600

475, illustrating that spread and proliferation of land-based ARGs in marine sediments might be mainly affected by anthropogenic and microbial factors. These findings provided new information on fate and drivers of ARGs in marginal sea.The ability of submerged aquatic plants (Elodea canadensis, Myriophyllum spicatum, Ceratophyllum demersum) and a natant plant (Eichhornia crassipes) to bioaccumulate mercury was evaluated in a laboratory experiment as well as in a real aquatic ecosystem situated in the vicinity of a cinnabar mine. Moreover, the ability of the diffusive gradients in the thin films technique (DGT) to predict mercury bioavailability for selected aquatic plants was tested. The submerged plants had sufficient bioaccumulation capacity for long-term phytoaccumulation of mercury in a real aquatic ecosystem. The determined bioaccumulation factor was greater than 1000. On average, the submerged plant leaves accumulated 13 times more mercury than the leaves of the natant aquatic plants. Chlorides at concentrations up to 200 mg/L had no statistically significant effect on mercury accumulation, nevertheless, the presence of humic acid in the water environment resulted in its significant (p 0.66) was determined between mercury concentration in the input parts (leaves and/or roots) of the aquatic plants and the flow of mercury into DGT units.Cellulose is the main polysaccharide present abundantly in the earth, an important substrate for the cellulase enzyme. Cellulases have attracted considerable attention due to its diverse application in different textile, detergent, leather, food, feed and paper industries. Among the cellulase producing microbes, bacteria have a faster growth compared to other microbes. The present study focuses on isolating bacterial strains (Bacillus pacificus and Pseudomonas mucidolens) from vermicompost. The study focused on extracting cellulase enzyme and its molecular weight using SDS-PAGE, which was determined to be 32Kda. The maximum enzyme activity resulted to be 0.12 U/mL and 0.17 U/mL after dialysis. The LDPE degradation was reported up to 30 days. Further, the growth conditions of the bacterial strains were optimised at different pH and temperature. The degradation of LDPE was determined using FTIR analysis, resulting in the peak changes (formation and shifts). The bacterial strains were morphologically characterized using Scanning Electron Microscopy. The bacterial strains Bacillus pacificus and Pseudomonas mucidolens were identified using 16 S rRNA sequencing.Vanillin and vanillic acid are two kinds of lignin pyrolysis products that are generated by biomass combustion. The gas-phase oxidation mechanisms of vanillin and vanillic acid initiated by OH/NO3 radicals were investigated by using density functional theory (DFT) at M06-2X/6-311+G(3df,2p)//M06-2X/6-311+G(d,p) level. The initial reactions of vanillin and vanillic acid with OH/NO3 radicals can be divided into two patterns OH/NO3 addition and H-atom abstraction. For vanillin reacted with OH radical, the OH addition mainly occurs at C2-position to produce highly chemically activated intermediate (IM2). The oxidation products 3,4-dihydroxy benzaldehyde, malealdehyde, methyl hydrogen oxalate, methylenemalonaldehyde, carbonyl and carbonyl compounds are formed by the subsequent reactions of IM2. H-atom abstracting from aldehyde group occurs more easily than from the other positions. In addition, vanillin reacting with NO3 radicals principally proceeds via NO3-addition at C1 sites and H-atom abstracting from OH group (C1) to generate HNO3. The primary reaction mechanisms of vanillic acid with OH/NO3 radicals were similar to vanillin. The Rice-Ramsperger-Kassel-Marcus (RRKM) theory was performed to calculate the rate constants of the significant elementary reactions. The total rate constants for OH-initiated oxidation of vanillin and vanillic acid are 5.72 × 10-12 and 5.40 × 10-12 cm3 molecule-1 s-1 at 298 K and 1 atm. The atmospheric lifetimes were predicted to be 48.56 h and 51.44 h, respectively. selleck As a supplement, the kinetic calculations of NO3 radicals with two reactants were also discussed. This work investigates the atmospheric oxidation processes of vanillin and vanillic acid, and hopes to provide useful information for further experimental research.Seven biochars (BCs) obtained from pyrolysis or gasification of different vegetal feedstocks were thoroughly characterized in comparison with three commercial activated carbons (ACs) routinely used in drinking water treatment plants. BCs and ACs characterization included the determinations of ash, iodine and methylene blue adsorption indexes, and the release of metals and polycyclic aromatic hydrocarbons, which were performed according to international standards applied for adsorption media to be used in drinking waters. Total specific surface area, micropore and mesopore specific surface area, pH of the point of zero charge, and the release of polychlorinated biphenyls were also determined in all chars. Principal component analysis and cluster analysis were performed in order to summarize the complex set of information deriving from the aforementioned characterizations, highlighting the BC most similar (BC6 from high temperature gasification of woody biomass) and most different (BC7 from low-temperature pyrolysis of corn cob) from ACs. These BCs were studied for their adsorption in ultrapure water towards diiodoacetic acid (an emergent disinfection by-product), benzene, and 1.2-dichlorobenzene, in comparison with ACs, and results obtained were fitted by linearized Freundlich equation. Overall, BC6 showed higher sorption performances compared to BC7, even though both BCs were less performing sorbents than ACs. However, the sorption properties of BCs were maintained also in real water samples collected from drinking water treatment plants.Uranium and vanadium commonly co-exist in groundwater aquifer where uranium was smelted from vanadium tailings. However, little is known about interrelationships of U(VI) and V(V) during their bio-reduction processes. In this work, 92.7 ± 1.52% U(VI) and 100% V(V) were simultaneously removed with sodium acetate as the sole exogenous electron donor and carbon source under anaerobic condition. Various conditions (i.e., increased uranium, reduced hydraulic retention time and acetate) were observed to affect removal efficiencies. Characterization of column fillings indicated that U(VI) was precipitated to U(IV) and V(V) was reduced to insoluble V(IV). Microbial community structure was observed to change, where Aquabacterium and Hydrogenophaga promoted bioreductions of U(VI) and V(V). Enriched Novosphingobium and Rhodobacter also played a vital role in reducing U(VI) and V(V). These findings could be used to study the biogeochemical fates of U(VI) and V(V) in the aquifer and to remediate groundwater co-contaminated by U(VI) and V(V).The present investigation has been carried out to utilize waste animal (Ox) bone for the progress of an innovative, low-budget, pollution free, and extremely resourceful heterogeneous catalyst synthesis for Jatropha curcas oil (JCO) conversion into biodiesel. The heterogeneous catalyst synthesized was characterized by its basic strength and subjected to spectroscopic (Fourier TransformInfrared and X-Ray Diffraction) and thermogravimetric analyses. Also, the physical properties of produced biodiesel were studied. The calcined Ox bone catalyst characterization distinctly showed that there was a tremendous catalytic activity for biodiesel synthesis. The kinetic study was accomplished employing a tri-necked RB flask furnished with a condenser and agitator. At the agitation speed of 500 rpm, 5% catalyst loading rate (w/w) of oil and 121 methanol-oil ratio (molar), biodiesel yields were tracked based on reaction time (1-4 h) and temperature (313-338 K). The temperature at 338 K was found to be optimal to obtain maximum (96.82%) biodiesel yield. Pseudo-first order kinetics was followed in the reaction. The energy required for the activation (Ea) was 38.55 kJ mol-1 with a frequency factor (ko) of 7.03 × 106 h-1. The reusability studies demonstrated that the calcined animal bone catalyst was much stable up to three cycles with >90% FAME yield, which was reduced significantly (P less then 0.05) to 61% in the fourth cycle. The outcome of this investigation brought to light the possibilities of utilizing calcined Ox bone catalyst and JCO as low-cost and frequently obtainable discarded waste materials that can be used as feedstock for the commercial-scale generation of biodiesel to fulfill the prospective community demands.Nanoplastics and carbon nanotubes (CNTs) is one of the emerging environmental contaminants and a widely used engineering nanomaterial, and their biological toxicity has been frequently studied. However, there has been no research on the combined exposure of these two totally different shape nanoparticles. To explore their potential threat to freshwater ecosystems, Microcystis aeruginosa (M. aeruginosa) was exposed to concentration gradients of polystyrene nanoplastics (Nano-PS) and multi-walled carbon nanotubes (MWCNTs). The physiological analysis and whole-transcriptome sequencing were integrated to certify the cytotoxicity. As the physiological results showed, the low concentration (5 mg/L) of these two nanoparticles showed a stimulation on the growth (6.49%-12.2%) and photosynthesis (0-7.6%), and the coexposure was slightly higher than individuals. However, other concentrations showed inhibitory effect, especially at high concentration (50 mg/L), and all physical signs and electron microscope images showed obvious cytotoxicity. Compared with the individuals, the coexposure showed an antagonistic effect induced by the heterogeneous agglomeration which decreased the surface toxicity and the contact with algae of nanomaterials. Transcriptome results showed that coexposure treatment had the fewest differential genes, and the primary effects embodied in the disturbances of cellular and metabolic processes which were superior to the individuals. In the 50 mg/L Nano-PS, the translation process was significantly disordered, and MWCNTs could disrupted the photosynthesis, multiple metabolism processes, membrane transport, and translation. These findings demonstrated the aquatic toxic mechanism from cellular and metabolic processes of Nano-PS and MWCNTs for M. aeruginosa and provided valuable data for environmental risk assessment of them.The aim of this study was to determine the kynurenine (KYN) to tryptophan (TRP) ratio (KTR) in fish tissue to assess its usefulness as a biomarker of acute stress. Laboratory held rainbow trout (Oncorhynchus mykiss) were subjected to an acute stressor and KYN, TRP and cortisol were measured in liver and brain tissues at 4- and 48-h post-stress. The analytical method used to determine our analytes was based on lyophilization, and liquid-solid extraction followed by isotope dilution high-performance liquid chromatography positive ion electrospray tandem mass spectrometry. The [KYN]/[TRP] ratio (KTR) was greater in fish liver and brain in the 48-h post-stress exposure group (n = 8) relative to controls (n = 8, p less then 0.05); a similar increase was not observed in fish in the 4-h post-stress exposure group. Hepatic and brain cortisol levels were also elevated in fish from both stress-induced groups relative to their respective controls implying that cortisol responded more quickly to the stressful stimulus than KYN and TRP.