• Sigmon Soelberg posted an update 1 week, 3 days ago

    Comparative studies of some major basalt watersheds in the world show that temperature, runoff and elevation differences significantly affect the chemical weathering rates and thus the accumulation of heavy metals.Magnetite nanoparticles (Fe3O4 NPs) was firstly used to enhance pollutants removal during coal gasification wastewater (CGW) treatment in anaerobic digestion (AD) system. Bench-scale results revealed that 200 mg/L and 20-40 nm of Fe3O4 NPs addition resulted in a maximum removal capacity of total phenol (TPh) at a temperature of 36 °C and hydraulic retention time (HRT) of 36 h. Meanwhile, Fe3O4 NPs addition reduced the oxidation reduction potential (ORP) values and biological toxicity, and enhanced the stability of AD system. Pilot-scale results showed that the TPh and chemical oxygen demand (COD) removal efficiency (53% and 49%) were obtained with the optimal dosage of Fe3O4 NPs. Moreover, electron nanowires may be established with Fe3O4 NPs assisted to perform direct interspecies electron transfer (DIET) among Geobacter, Pseudomonas and Methanosaeta species, and finally enhanced the pollutants removal efficiency.Chromium is a toxic heavy metal. Plants, animals and human metabolic processes are disturbed due to higher levels of chromium. PGPR are involved in seed germination, growth improvement, metabolic process and in most of the physiological processes of plants. Press mud in soil provides substrate to the microbes. PGPR can convert the more toxic form of Cr (VI) into less toxic form Cr (III). This study was conducted to find out the reduction potential of pre-isolated rhizobacteria and their role in strengthening of plant growth and physiological attributes. Soil collected from the research area was spiked with 20 mg kg-1 of Cr (VI) by using potassium dichromate (K2Cr2O7) salt before sowing. Results revealed that Cr (VI) significantly suppressed the shoot length, root length and photosynthetic rate of okra up to 19, 37 and 31%, respectively. However, inoculation decreases the uptake of Cr (VI) in root and shoot up to 37 and 31% and by press mud 33 and 20%, respectively. Combined application of inoculation and press mud significantly recovered the negative impact of chromium and plant growth was almost at par compared with contaminated treatment without inoculation.In this study, goethiete (α-FeOOH) -biochar (BC) composites were successfully developed from a co-precipitation reaction under alkaline conditions (pH = 11.93) and used as the adsorbent for phosphate recovery from urine. The morphology and crystallinity of α-FeOOH-BC composites were characterized by scanning electron microscopy and X-ray diffraction. α-FeOOH loaded BC was found to be amorphous. This may be caused by the Si residue in BC. The Elovich model and the Langmuir model fit better to the kinetic and isotherm results of α-FeOOH-600BC, respectively, indicating that phosphate adsorption is mainly a chemisorption and monolayer adsorption process. The α-FeOOH-600BC with amorphous structure showed higher adsorption capacity than crystalline α-FeOOH, and the maximum phosphate sorption capacity reached 57.39 mg g-1. Additionally, the extractable phosphate of this material was approximately 967.5 mg P·kg-1 suggesting the α-FeOOH-600BC after adsorption could be a promising alternative as a slow-phosphate-release fertilizer. Fourier-transform infrared and X-ray induced photoelectron spectroscopy results showed that the active sites of the adsorption of phosphate were the Fe-OH bonds that formed inner-sphere complexes (Fe-O-P).The study was conducted to investigate the influence of the culture pattern on plant uptake and translocation of an organic chemical and the resultant acute response of plants, and to further reveal the interconnection. Plant exposure experiments were performed using a conventional rice seedling (Oryza sativa L. subsp. indica) under two kinds of culture patterns (viz., hydroponics and soil-based culture) with various culture matrices for a period of 7 days. The exposure concentration of lindane was ∼450 μg L-1 in the aqueous-phase matrices, and 200.1-756.0 μg kg-1 in the solid matrices. Lindane accumulation and its distribution in plant tissues were quantified, as well as the tissue biomass. The results showed the accumulation of lindane in all exposure groups were comparatively close over the period, confirming that the soil-bound lindane was scarcely available to plants. Similar trend of lindane uptake and translocation in seedlings was found among the groups under the same kind of cultivation pattern. In the hydroponic groups, lindane was mostly distributed in roots (about 60% at the end of exposure), whereas more lindane was translocated to shoots (approximate 70%) under the soil-based culture pattern. Allometric analysis demonstrated that the tissue part (root or shoot) with more lindane accumulation had a relatively higher growth rate over 7 days. Correspondingly, biomass allocation presented a slight trend of mutual proximity to lindane distribution. It was inferred that plants altered their allometric growth pattern to realize biomass re-allocation in response to the short-term lindane exposure, which could be considered as a plant defense strategy.In this study, cost-effective cellulosic biomass based activated wood charcoal was developed from Japanese Sugi tree (Cryptomeria japonica) by concentrated nitric acid modification for adsorption of Cs from contaminated water. The physicochemical properties of specimens were investigated using N2 adsorption-desorption isotherms (BET method), FESEM, FTIR, and XPS spectra analysis. The experimental results revealed that the surface area of the raw wood charcoal was significantly decreased after boiling nitric acid modification. However, several oxygen-containing acidic function groups (-COOH, -CO) were introduced on the surface. The adsorption study confirmed that the equilibrium contact time was 1 h, the optimum adsorption pH was neutral to alkaline and the suitable adsorbent dose was 1100 (solid liquid). The maximum Cs was removed when the concentration of Na and K were lower (5.0 mM) with Cs in solution. Bomedemstat The Cs adsorption processes well approved by the Langmuir isotherm and pseudo-second-order kinetic models and the maximum adsorption capacity was 35.