Microbial etch: A novel construction method of functionalized biochar for enhanced uranium extraction in radioactive wastewater.

Nuclear energy is playing an increasingly important role on the earth, but the nuclear plants leaves a legacy of radioactive waste pollution, especially uranium-containing pollution. Straw biochar with wide sources, large output, low cost, and easy availability, has emerged as a promising material for uranium extraction from radioactive wastewater, but the natural biomass with suboptimal structure and low content of functional groups limits the efficiency. In this work, microbial etch was first came up to regulate the biochar's structure and function. The surface of the biochar becomes rougher and more microporous, and the mineral contents (Ca, P) indirectly increased by microbial etch. The biochar was modified by calcium phosphate and exhibited a remarkable uranium extraction capacity of 590.8 mg g-1 (fitted value). This work provides a cost-effective and sustainable method for preparing functionalized biochar via microbial etch, which has potential for application to uranium extraction from radioactive wastewater.

Output characteristics of series-parallel triboelectric nanogenerators.

To tackle the problem of the low output power of triboelectric nanogenerators (TENGs), the output characteristics of multiple TENGs in series and parallel were explored. An experimental device for multilayer TENGs was developed. Through the method of experimental modeling, the equivalent circuits and mathematical models in series and parallel are established respectively, and the working principle is expounded. The experiment found that when multiple TENGs are connected in parallel, the voltage, current, and output power can be regularly increased. When the TENGs are connected in series, the output power is only related to the performance of the first and last two triboelectric generators and has nothing to do with the number of series-connected TENGs. This finding has a certain reference value for the design of high-efficiency triboelectric nanogenerators.

Wulingshen, the massive Xylaria sclerotia used as traditional Chinese medicine, is produced by multiple species.

Wulingshen, massive Xylaria sclerotia, was originally reported from Chengdu Plain in western Sichuan of China for medicinal application. Xylaria nigripes is commonly connected to these massive sclerotia produced within abandoned underground macrotermitine termite nests. We sequenced 54 Wulingshen samples procured from traditional Chinese medicine markets in Chengdu Plain and connected them to six different Xylaria species: X. nigripes, X. subescharoidea, two species newly described herein-X. neonigripes and X. rogersionigripes, and two species that are known only as sclerotia thus far. Only teleomorphs of X. subescharoidea and X. rogersionigripes have been collected in Chengdu Plain thus far. In Taiwan, teleomorphs of four of the six species, except for the two only known in sclerotial form, have been collected, and their cultures were obtained; we thus designate the holotypes of X. neonigripes and X. rogersionigripes on the basis of Taiwan specimens. During the collecting activities carried out in Chengdu Plain, a Xylaria species, which is newly described as X. mianyangensis herein, was also collected from termite nests but lacks a known connection to Wulingshen.

Electromagnetic Wave Absorption and Mechanical Properties of CNTs@GN@Fe3O4/PU Multilayer Composite Foam.

With the development of intelligent communications and stealth technology in the military field, electromagnetic wave pollution cannot be ignored, and absorbing materials have entered people's field of vision and gradually become a research hotspot. The ideal absorbing material should have the characteristics of "strong, wide, thin, and light", but a single absorbing material often cannot meet the above conditions. At present, absorbing metal powder combined with two-dimensional carbon nanomaterials (such as carbon nanotubes, graphene, etc.) has became a trend. This article focus on a three-layer composite of Fe3O4, Carbon nanotubes@ Fe3O4, Carbon nanotubes@Graphene nano-platelets@ Fe3O4, which was synthesized by solvothermal method. The results show that the electromagnetic wave absorption performance of the three-layer foam at a thickness of 3.0 mm is more excellent. The minimum of RL can reach -67.0 dB, and the effective bandwidth is above 5.0 GHz. All this is due to the synergy of dielectric and magnetic loss between Fe3O4, CNTs, and GN, the increase of interface polarization and the path of electromagnetic wave reflection and scattering by three-layer foam.

Heavy metal fixation of lead-contaminated soil using Morchella mycelium.

With the exploitation of lead-zinc deposits, lead content around mining areas has seriously exceeded the recommended level. The most challenging problem is how to reduce lead contamination in soil efficiently. In this study, we developed a method to remediate lead-contaminated soil by adding Morchella mycelium. First, we compared the repair effects of mycelium and hyperaccumulator by conducting pot experiments. Then, we investigated the mechanism through which mycelium repairs lead-contaminated soil by conducting simulation experiments. Results showed that using mycelium was a more efficient way to repair soil than using hyperaccumulator. Compared with the untreated group, mycelium reduced the lead content of crops by 34.83 % and raised dry biomass by 134.05 % when lead addition was 800 mg/kg. After mycelium fixation, soil catalase, urease, cellulase, and sucrase activities were significantly enhanced, and the bioavailability of lead decreased significantly. The lead solution exposure simulation test showed that Morchella mycelium immobilized lead due to its extracellular secretions. That is, mycelium secreted metabolites and lead to form salt crystals, reducing bioavailable lead content. In addition, Morchella mycelium restoration may effectively improve soil fertility and increase crop yields. Thus, mycelium may be used successfully in alternative green repair methods for environmental heavy metal remediation.

Highly stretchable and self-foaming polyurethane composite skeleton with thermally tunable microwave absorption properties.

Stretchable and lightweight polymer composite material possessing tunable microwave absorption (MA) properties under thermal radiations remain a significant challenge. Here, we proposed a facile strategy to fabricate stretchable, magnetic composite skeletons by incorporating the tadpole-like CNTs@Fe3O4nanoparticles into self-foaming polyurethane (PU) matrix and the electromagnetic responsive of CNTs@Fe3O4/PU composite foams with different CNTs contents under heating-cooling cycle in a temperature range of 253 -333 K were carefully investigated. Enhanced complex permittivity and shifting peak frequency were observed at elevated temperatures. For instance, the 70-CNTs@Fe3O4/PU sample with 15 wt% loading content at 333 K exhibits excellent MA properties including a minimum reflection loss (RLm) of -66.9 dB and ultrabroad effective frequency bandwidth (RL ≤ -20 dB) of 9.98 GHz at the thickness of 1.58-3.37 mm. Meanwhile, great recoverability in terms of RL-fprofile was achieved in the process of thermal cooling back to 253 K. Such adjustable MA property was attributed to the well-matched impedance and dramatic attenuation ability, benefiting from the temperature-dependant electrical conductivity, abundant interfacial polarization and interior microcellular structures. Besides, the rising temperature increased the sample elongation and electrical conductivity with a slight sacrifice of maximum tensile strength. This stretchable PU skeleton with a unique assembly of CNTs and Fe3O4nanoparticles are expected to be promising candidates as smart absorbers for application in the harsh environments.

A novel effect of combining microorganisms and graphene oxide for solidifying simulated nuclides strontium.

Inspired by microbial diagenesis and mounding, microbial mineralization technology has been widely used in the treatment of heavy metal and radionuclide contamination. S. pasteurii can decompose urea as a source of energy to produce CO32- in the microbial mineralization system. Therefore, strontium-contaminated radioactive wastewater can be effectively treated by combining CO32- with surrounding strontium ions (Sr2+) to form strontium carbonate (SrCO3). Herein, we investigated how the concentration of graphene oxide (GO) and mineralization time influence the morphology of SrCO3 and the mineralization efficiency. GO was used as a crystal regulator to solidify the radionuclide strontium in the microbial mineralization system to obtain large-scale rock-like SrCO3 minerals. The results showed that GO can adsorb the surrounding Sr2+ with oxygen-containing functional groups on its surface to form SrCO3 complexes, directly influencing the morphology and consolidation percentage of SrCO3. Considering the leaching behaviour of nuclides, we further studied the stability of consolidated SrCO3 minerals. The results indicated that the presence of GO improved the stability of the mineralized samples obtained in the microbial mineralization system.

Formation of N-nitrosodimethylamine precursors through the microbiological metabolism of nitrogenous substrates in water.

N-nitrosodimethylamine (NDMA) as one emerging disinfection by-product has been investigated globally since 1990s. However, its main precursors are still unclear. We found that NDMA formation potential (NDMAFP) of various water samples increased firstly and then decreased gradually during incubation with microorganism. We hypothesized that NDMA precursors could be produced through metabolism of nitrogenous components and then gradually be biodegraded. To verify this hypothesis, six amino acids (AAs), peptone and ammonium were separately incubated with microorganism and NDMAFP was measured regularly. The average molar yield of the substrates to NDMAFP were 60-200 × 10-6 for the AAs, 350 × 10-6 for peptone under aerobic condition. The extracellular fraction with molecular weight (MW) less than 1 k Dalton contributed the majority to NDMAFP in the peptone experiment, followed by that with MW between 10 k and 0.22 µm and the intracellular materials. Dimethylamine and methylamine were detected during the experiments but their contribution to NDMAFP is quite limited. The results indicate that the nitrosamine precursors may not be the direct metabolite of AAs or peptones but the excretion of living bacteria or the components in dead bacteria body. Our results inferred that AA metabolism may give an NDMAFP of 0.12 nmol/L (maximum) or 0.09 nmol/L (average) in water under aerobic condition. This estimation of NDMAFP from AA metabolism can account for 38% (maximum) or 27% (average) of the median NDMAFP in waters of China (0.32 nmol/L) reported before.

Xylastriasan A, a new cytochalasan from the fungus Xylaria striata.

Xylastriasan A (1), a new cytochalasan alkaloid with a rare 5/6/6/5/6 pentacyclic skeleton, and ergosterol (2) were isolated from the ethanol extract of fruiting bodies of the fungus Xylaria striata. Their structures were determined by analysis of their spectroscopic data. Compound 1 exhibited weak cytotoxic activity against HEPG2, B16 and A549 cell lines with IC50 values of 93.61, 85.61 and 91.58 µM, respectively. Ergosterol (2) potentiated pentobarbital-induced sleep by not only increasing the number of falling asleep and prolonging sleeping time but also reducing sleep latency at a dosage of 5 mg/kg.

[Optimization of submerged culture conditions for Xylaria striata mycelium].

OBJECTIVE: To establish the optimum submerged culture condition of Xylaria striata mycelium. METHODS: One-factor-at-a-time method and orthogonal experiment design were applied and the dry weight of mycelium was tested for evaluation the biomass of the growth of Xylaria striata mycelium. RESULTS: The results from one-factor-at-a-time experiments showed that maltose, glucose or corn powder could be used as the best carbon source and the optimum nitrogen source was soybean powder. The best ratio of carbon source to nitrogen source was 5:1. In addition, the higher dry weight of mycelium was found at pH 6 when 2 mycelial discs were inoculated and fermented for 7 days. Otherwise, the growth of mycelium was observed to be promoted significantly by addition with K,Mg,P and VB1. The consequence of orthogonal experiment showed that the optimum carbon source and nitrogen source were maltose 4% and soybean powder 0.8%, respectively,and the highest mycelium biomass could be obtained at pH 7 and 25 °C shaking for 13 days. CONCLUSION: A large amount of mycelium will be obtained under the optimum condition of liquid culture for Xylaria striata.

Xylaria coprinicola, a new species that antagonizes cultivation of Coprinus comatus in China.

The species known in China as the chicken-claw fungus is described as a new species, Xylaria coprinicola. This species is known as an antagonist of cultivation of the edible mushroom Coprinus comatus. Stromata of X. coprinicola are cylindrical, terminate in a sterile apex and arise in fascicles from a relative large submerged base; perithecia are immersed and have conspicuously conical ostiolar openings; ascospores are minute. Phylogenetic analyses based on combined partial sequences of rpb2, ß-tub and α-act genes showed that X. coprinicola is closely related to those Xylaria species exclusively associated with termite nests.

[Kinetic model for exopolysaccharides (EPS) of Ganoderma lucidum in batch fermentation].

The synthetic characteristic of extracellular polysaccharide (EPS) of Ganoderma lucidum performed in batch fermentation was studied. The result showed that the production EPS was partially growth-associated. The cell dry weight (CDW) and EPS reached 15.56 g x L(-1), 3.02 g x L(-1) respectively. The yield of EPS to cell dry weight ( Y(p/x)) was 0.19. Based on the test result of batch fermentation, a kinetic model was proposed by using the Logistic equation for cell growth, the Luedeking Piret equation for EPS production and the Luedeking-piret-like equation for consumption of glucose as substrate. The calculated results of models were compared satisfactorily with experimental data under various glucose concentrations, the average relative error was no more than 5%. The kinetic model had practically guiding producing PES in fermentation of Ganoderma lucidum.

[The expression of migration inhibitory factor in peripheral blood mononuclear cell and its correlation with disease activity in systemic lupus erythematosus].

OBJECTIVE: To investigate the change of macrophage migration inhibitory factor (MIF) mRNA expression in peripheral blood mononuclear cell (PBMC) and serum MIF and its correlation with disease active index in patients with systemic lupus erythematosus (SLE). METHODS: MIF mRNA expression of PBMC and serum MIF in patients with active and inactive SLE was measured by reverse transcriptase-polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. The correlations of serum MIF with SLE disease active index, serum ds-DNA antibody, ANA, C3, C4 and IgG were examined. RESULTS: There was marked increase in MIF mRNA expression of PBMC and serum MIF in patients with SLE than that in normal volunteers (P < 0.01). Level of MIF in patients with active SLE was higher than that with inactive SLE (P < 0.01). There were significant correlation between the blood MIF concentration, MIF mRNA expression and SLE disease active index, ds-DNA antibody, C3, C4 and IgG, but no significant different was observed between the blood MIF and antinuclear antibody. CONCLUSIONS: MIF mRNA expression in PBMC and serum MIF concentration is significantly increased in patients with SLE and correlates with SLE disease activity. Serum MIF levels may be a useful parameter for monitoring disease active in patients with SLE.