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CVD molybdenum disulfide (MoS2) is shown to chemically oxidize rapidly after pure oxygen plasma bombardment. Atomic force microscopy (AFM), photoluminescence spectrum (PL), Raman spectrum and X-ray photoelectron spectroscopy (XPS) are employed to characterize the physical and chemical properties and indicate that MoO3 is easily formed from MoS2. The result of AFM shows that thickness of the film increases from 0.9 to 1.79 nm after oxygen plasma treatment, which is mainly due to the difference in lattice structure between pristine MoS2 and generated MoO3. XPS analysis shows that the intensity of the S2s peak is reduced to 0 after oxygen plasma treatment. Also, the intensities of Mo4+ peaks disappear at 233.2 eV and 230 eV, leaving only the Mo6+ peaks at 232.5 eV and 235.65 eV, which strongly proves the transformation of MoS2 to MoO3. Further, we use oxygen plasma to treat few-layer MoS2, and find that the top oxidized layer can protect the lower MoS2 from further oxidation. Finally, we obtain p-type doped transistors with this method. [ABSTRACT FROM AUTHOR]

BACKGROUND Tetracycline (TC) residues in water and soil have received wide attention due to their adverse effects on human health and ecosystem. Layer‐structured biogenic manganese oxides (BMOs) could be obtained from fungi Pleosporales sp. Y‐5 culture. Cobalt doping into BMOs (Co‐BMOs) was conducted by a facile impregnation‐calcination method to eliminate TC residues through activation of peroxymonosulfate (PMS). RESULTS: The TC in aqueous solution could be nearly completely removed in about 10 minutes under the optimal condition ([TC] = 50 mg L−1, [catalyst] = 0.2 g L−1, [PMS] = 0.4 g L−1, 25°C). The electron paramagnetic resonance (EPR) identified the coexistence of SO4−• and OH• during PMS activation. The Co‐BMOs catalyst remained great catalytic activity after five runs. Possible mechanism of PMS activation and TC degradation pathway were proposed. Preliminary biological toxicity test using green algae Chlorella vulgaris (FACHB‐8) as ecological indicator confirmed that TC degradation solution was less toxic than the original solution. CONCLUSION: This study demonstrated high catalytic activity and stability of Co‐BMOs for degradation of TC by PMS activation. The Co‐BMOs/PMS system is helpful in new efforts for TC degradation without generation of more toxic intermediates. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

In this study, jarosite waste was adopted as feed material for micaceous iron oxide (MIO) pigment preparation by a one-pot hydrothermal reaction. The formation of MIO started from jarosite decomposition into akaganeite (β-FeOOH) nanoparticles in alkali solution, which then recrystallized and transformed into MIO crystals under high temperature and OH− concentration. The influences of NaOH concentration and reaction temperature on MIO formation were investigated. It was found that MIO formed when NaOH concentration and reaction temperature were equal to or higher than 2 M and 180°C, respectively. With an increase of NaOH concentration or reaction temperature, the particle size of MIO increased, leading to darkened color of the product. Moreover, quality evaluation indicated that the synthesized MIO fulfilled the required characteristics of micaceous iron oxide pigments for paints and the international standard of ISO 10601-2007 MIO-A1. [ABSTRACT FROM AUTHOR]

CuFeMnO spinel oxide was synthesized by co-precipitation method through calcination of the precipitate precursor at 500-900 °C. The reaction process was investigated by thermogravimetric analysis (TG), differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The structure, valence state and magnetic properties of the powders obtained were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and vibrating sample magnetometer (VSM) further. The results revealed that the precipitate is composed of amorphous metal hydroxides and oxides, after which the spinel structure and several phases, such as CuO, FeO and MnO, turned up in the calcined powders. As the calcining temperature raising, these phases began to transform into a single phase of CuFeMnO. However, CuO phase segregated from the spinel structure with further calcining. The valence state of Mn ions in octahedral sites and Cu ions in tetrahedral sites were ascertained by XPS, which showed the reduction of Mn and Cu during the calcining procedure. Besides, the magnetization of the samples increased obviously with the calcining temperature. [ABSTRACT FROM AUTHOR]

Metal-free carbon catalysts perform well in peroxymonosulfate-based advanced oxidation process for the treatment of organic pollutant-containing wastewater. Herein, a natural biomolecule of adenosine triphosphate (ATP), containing abundant N and P elements, served as sole precursor to prepare N,P-co-doped carbon through one-step anoxic pyrolysis, which was applied as peroxymonosulfate activator to treat bisphenol-contaminated water. Owing to the endogenous N and P elements in ATP, in-situ doping was achieved for the prepared carbon material with excellent doping effect, such as high doping amount and numerous defects. During pyrolysis process, the generated gases facilitated the exfoliation of carbon structure, resulting in a nanosheet-like morphology with large specific surface area, e.g., 852.75 m2 g−1 for NPCN-900 sample obtained at 900 °C. Benefiting from the structural modulation brought by N,P co-doping, typical sample of NPCN-900 presented excellent catalytic performance towards bisphenol AF (BPAF) degradation through PMS activation. An apparent reaction rate constant of 0.4115 min−1 was calculated under the investigated reaction conditions. Further studies indicated that 1O 2 , surface-bound •OH and SO 4 −• worked together in NPCN-900/PMS system for BPAF degradation. Graphitic N, pyrrolic N, C O groups, defect structure and the doped P atoms in NPCN-900 contributed to PMS activation. It was also important that the toxicity of BPAF solution could be preliminarily eliminated after treatment by NPCN-900/PMS system, which was verified by ecotoxicity assessments through ECOSAR program and green algae growth experiments. [Display omitted] • N,P-co-doped carbon (NPCN) was obtained using ATP as sole precursor. • NPCN possessed nanosheet-like structure with surprisingly high specific surface area. • NPCN could efficiently activate PMS, resulting in fast degradation of bisphenol pollutant. • Reactive sites on NPCN and reactive oxygen species generation process were investigated. • Preliminary detoxification of BPAF was realized by NPCN-900/PMS catalytic system. [ABSTRACT FROM AUTHOR]

Peroxymonosulfate (PMS) activation technology represents an efficient approach to generate reactive oxygen species for treating pharmaceutical pollutants, and the fabrication of effective catalysts is of great significance for PMS activation technology. In this study, iron-manganese (Fe-Mn) layered double oxides (LDO) with flaky structure formed by metal oxide nanoparticles were synthesized by coprecipitation-calcination method and used to activate oxidant PMS to generate reactive oxygen species so as to realize the degradation of sulfathiazole (STZ). Benefiting from the well-dispersed structure and synergistic effect between bimetallic oxides, about 90% of STZ (20 mg L−1) could be removed with the dosage of catalyst (LDO-400, 0.4 g L−1) and PMS (0.4 g L−1) in 40 min catalysis process. Quenching experiments and in-situ electron paramagnetic resonance (EPR) analysis revealed that radical pathways dominated by surface-bound SO 4 −• and •OH were involved in the removal of STZ in LDO-400/PMS system. Besides, EPR and linear sweep voltammetry (LSV) analysis indicated the non-radical pathways containing 1O 2 and electron transfer also contributed to STZ degradation. Five consecutive cycles were conducted to prove the stability and reusability of LDO-400. The intermediates in the STZ degradation process were identified to propose the STZ degradation pathways. Particularly, ecological structure-activity relationship (ECOSAR) predicted the relatively low ecological risk of LDO-400/PMS system for STZ degradation. This study not only proves the advantages of synergistic effect between bimetallic oxides, but also enriches the design strategy of environmental remediation. [Display omitted] • Fe-Mn layered double oxides were obtained by a coprecipitation-calcination method. • Fe-Mn layered double oxides effectively activated peroxymonosulfate for sulfathiazole removal. • SO 4 −•, •OH, 1O 2 and electron transfer contribute to sulfathiazole removal. • The redox cycles of well-dispersed Fe and Mn were crucial for peroxymonosulfate activation. • The degradation intermediates exhibited relatively low ecotoxicity compared with sulfathiazole. [ABSTRACT FROM AUTHOR]

Kitchen waste (KW) is a worldwide issue, which can lead to environment pollution. Nevertheless, it is also a low-cost and sustainable resource for bio-production. Meanwhile, welan gum (WG) is one kind of the most important exopolysaccharide but with high material cost. The aim of this study was to adopt two-step enzymatic hydrolysis to improve the release and recovery of both sugar and protein in KW for subsequent WG production. As the results, the recovery rates of sugar and protein reached 81.07 and 77.38%, which were both satisfactory. After the conditions optimized in flasks, the welan fermentation was conducted in a 5-L fermentor, and the WG yield, utilization rates of reducing sugar and KDN, respectively, reached 5.57 g L, 94.25% and 61.96%. Moreover, the kinetic analyses demonstrated that the WG fermentation in KWH was a partly growth-associated process. The KW was successfully treated by fermentation for the bioconversion to WG. [ABSTRACT FROM AUTHOR]

Octyl gallate (OG) is an internationally recognized antioxidant that demonstrates selective and sensitive fluorescent property. The fluorescence of OG can be selectively enhanced in the presence of human serum albumin (HSA) and bovine serum albumin (BSA). The specific structures of HSA and BSA provided the basic conditions for fluorescence enhancement. OG yielded approximately 49- and 11-fold increments in emission intensity in the presence of HSA and BSA at a molar ratio of 1:1, respectively. The lifetimes of HSA and BSA correspondingly decreased. A Förster resonance energy transfer phenomenon occurred during interaction between OG and HSA or BSA. Our in-depth investigation of OG–HSA interaction showed that formation of a stable complex was an important prerequisite to efficiently enhance the fluorescence of OG. The selective and sensitive fluorescent property of OG can possibly be used to determine OG concentration via the standard addition method, which must be performed under certain conditions. [ABSTRACT FROM AUTHOR]

BACKGROUND Food waste has great potential for biotech processing but most waste is subject to traditional disposal methods, losing its value. To alleviate economic and environmental concerns, the hydrolysate of food waste could be utilized for biolipid and protein production by Rhodosporidium toruloides Y2. RESULTS The biomass, lipid production and protein production reached 32.1 g L−1, 7.3 g L−1 and 7.0 g L−1, respectively. The composition of fatty acids and amino acids indicated that R. toruloides Y2 grown in food waste hydrolysate had the potential to be feedstock for biolipid and microbial protein production. Model prediction using the Logistic, Luedeking-Piret equation and modified Luedeking-Piret equation could estimate the growth, lipid production and reducing sugar utilization of R. toruloides Y2 in food waste hydrolysate. CONCLUSION The alternative proposed for converting food waste into microbial biomass is applicable. Food waste hydrolysate is suitable for lipid and protein production by R. toruloides Y2, without any additional nutrition or detoxification procedure. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

• Achyranthoside D is effective in relieving ACLT-MMx-induced osteoarthritis in rats. • Achyranthoside D inhibits NLRP3 inflammasome-triggered inflammation in rats. • Achyranthoside D attenuates IL-1β-induced chondrocyte loss in vitro. • Achyranthoside D inhibits NLRP3 inflammasome-triggered inflammation in vitro. • Achyranthoside D exerts anti-osteoarthritis effects via targeting Wnt3a. Achyranthes bidentata Blume (A. bidentata) is a common Chinese herb used to treat osteoarthritis (OA). Achyranthoside D (Ach-D) is a glucuronide saponin isolated from A. bidentata. To assess the mechanisms of action of Ach-D and its effects on OA. The effects of Ach-D were evaluated in rats underwent anterior cruciate ligament transection (ACLT) with medial meniscectomy (MMx) and in interleukin (IL)-1β-induced chondrocytes. Histological changes in rat cartilage tissues were detected using Safranin O-Fast green and haematoxylin-eosin staining. Immunohistochemical staining, qRT-PCR, ELISA, immunoblotting, and immunofluorescence were conducted to examine cartilage degeneration-related and inflammation-related factor expression. CCK-8, LDH assay, and EdU staining were performed to detect chondrocyte death. Ach-D dose-dependently reduced the Osteoarthritis Research Society International (OARSI) scores, alleviated cartilage injury, and decreased the serum concentrations of CTX-II and COMP in ACLT-MMx models. Ach-D increased the expression levels of collagen II and aggrecan and decreased the levels of cartilage degeneration-related proteins, ADAMTS-5, MMP13, and MMP3, in rat cartilage tissues. Additionally, nod-like receptor protein 3 (NLRP3)-related inflammation was reduced by Ach-D, as shown by the significantly inhibited expression levels of NLRP3, ASC, GSDMD, IL-6, TNF-α, IL-1β, and IL-18 in rat cartilage tissues. In primary rat chondrocytes, Ach-D protected against IL-1β-induced viability loss and LDH release. Wnt3a is the target protein of Ach-D. Mechanistically, Ach-D alleviated OA by inhibiting Wnt signalling. ACH-D may reduce inflammation and cartilage degeneration by inhibiting the Wnt signalling pathway, thereby reducing OA. [Display omitted] [ABSTRACT FROM AUTHOR]

ABSTRACT BACKGROUND To compete with chemical hydrogenation, xylitol production by a biotechnological method has to decrease production cost by improving the performance of the strain, using low-cost substrate and developing a simple and efficient bioprocess. This study attempted to reach high-efficient xylitol production using cheap substrate. RESULTS A new evolved strain, Candida maltosa CHH65 showed improved cell growth in corncob hemicellulosic hydrolyzate ( CHH) and similar product performance using xylose and CHH as substrate, was developed by serial culture transfer for adapting to CHH and solving the problem of inhibition of CHH. The new strain was recycled at least four times and still produced xylitol. In the test conditions, xylitol concentration reached more than 100 g L−1 within 48 h, with yield > 0.73 g g−1, and productivity > 2 g L−1 h−1 when using CHH as substrate. CONCLUSION The capability of the xylose-fermenting C. maltosa to convert CHH to xylitol was greatly enhanced so that the newly developed bioprocess for xylitol production from low-cost substrate with multiple recycled C. maltosa could be suitable for industrial application and reduce the production cost. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

In this work, microorganism of Phanerochaete chrysosporium with iron-tolerating and accumulating abilities was cultivated and harvested as mycelial pellets, which could serve as a sustainable and environmental-friendly precursor for iron phosphide/N-doped biocarbon composite preparation. Through one-step pyrolysis process, the inherent Fe and P elements in mycelial pellet enabled the formation of well crystallized Fe 2 P particles, loading on N-doped biocarbon matrix. Benefiting from the porous structure, high specific surface area, N doping-induced defects and C O groups of biocarbon, as well as the good electron-donating property of Fe 2 P, the as-obtained Fe 2 P/BC composite performed well for bisphenol pollutant (e.g., BPAF) removal through peroxymonosulfate (PMS) activation. Specifically, almost complete BPAF removal was achieved within 30 min adsorption and 10 min catalysis process with an apparent reaction rate constant of 0.486 min−1. The good crystallinity and protective carbon layer wrapping on Fe 2 P enabled the wide pH adaptability and low iron leaching of Fe 2 P/BC in catalytic reaction. Inorganic anions and humic acid brought only slight inhibition for BPAF removal, which could be overcome by prolonging reaction time to 30 min. Further mechanism studies indicated that reactive oxygen species, e.g., SO 4 -•, •OH and 1O 2 were generated through both radical and non-radical pathways and contributed to BPAF degradation. After treatment by Fe 2 P/BC-PMS system, the total organic carbon (TOC) of original BPAF solution (20 mg L−1) was reduced by 51.6%. Fortunately, the residual degradation intermediate products showed much reduced ecotoxicity in both predicted (ECOSAR program) and experimental results (growth inhibition test using Raphidocelis subcapitata as ecological indicator). [Display omitted] • Fe-containing mycelial pellet served as sole precursor for Fe 2 P/BC composite preparation. • Both Fe 2 P particles and biocarbon matrix contributed to PMS activation. • Low iron leaching was observed in Fe 2 P/BC-PMS catalytic system. • BPAF degradation was dominated by 1O 2 , surface-bound SO 4 -• and •OH. • ECOSAR and growth inhibition test implied the detoxification of BPAF by Fe 2 P/BC-PMS system. [ABSTRACT FROM AUTHOR]

Cassava bioethanol wastewater treatment using low-grade pyrolusite as oxidant in sulfuric acid solution was investigated. In order to obtain the optimal level and optimal combination of factors for high COD (chemical oxygen demand) removal rate of cassava bioethanol wastewater, orthogonal experiment was employed. The results indicated that the COD removal rate which depended more on the H2SO4concentration, could reach 94.56% under the conditions of H2SO4concentration of 2.5 mol/L, temperature of 90°C, reaction time of 90 min, and liquid-to-solid ratio of 2 mL/g. A shrinking core model was applied to describe the treating process, and the results revealed that the leaching rate increased with the increase in temperature, concentration of cassava bioethanol wastewater and sulfuric acid. Apparent activation energy for this model was calculated to be 33.05 kJ/mol, the reaction order of H2SO4concentration was 1.12 and cassava bioethanol wastewater concentration was 0.73. And the kinetics analysis showed that the reaction was controlled by the diffusion through the product layer composed of the associated minerals. [ABSTRACT FROM PUBLISHER]