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The concrete slurry waste (CSW) produced by concrete mixing plants is a type of hazardous waste that is difficult to handle. To better recycle the CSW separated from the aggregates, this study uses a variety of wet-grinding processes to refine the solid in it, replaces some of the cement with the solid particles in wet grinding concrete slurry waste (WCSW), and investigates the properties of WCSW and its effect on the hydration and hardening properties of cement. The results show that a suitable wet-grinding process can ensure that the particle size in WCSW is less than 10 μm, the particle morphology is more flat, and the degree of hydration is higher. The WCSW particles can promote early cement hydration; after adding WCSW, the heat release peak of cement hydration appears earlier and more early hydration products are produced, and with the increase in the substitution amount, the promoting effect on early cement hydration will be more significant. The WCSW particles have a great effect on improving the strength of mortar, especially in the early stage. At 1 d, when the substitution amount is 7.5 wt.%, the compressive and flexural strength is increased by 43.67% and 45.04%; this is related to the filling of matrix pores and the improvement of the interface transition zone by micro- and nanoparticles. After the wet grinding of CSW, fine WCSW particles are obtained, which can improve the performance of cement-based materials by replacing cement. [ABSTRACT FROM AUTHOR]

This study was conducted to determine the correlation among serum biochemical indices, slaughter traits, texture characteristics and water-holding capacity in Tan sheep. Eighty Tan sheep aged 4–6 months were selected. Blood samples were collected from live animals to analyse serum biochemical indices. The slaughter traits, texture characteristics and water-holding capacity of meat were assessed after slaughter. There were highly significant correlations (p<.01) and high linear regression R values among serum biochemical indices, slaughter traits, meat texture characteristics and water-holding capacity in Tan sheep. Therefore, this study has demonstrated that the meat qualities of Tan mutton may be evaluated by the serum biochemical indices of live Tan sheep. This study was conducted to determine the correlation among serum biochemical indices, slaughter traits, texture characteristics and water-holding capacity in Tan sheep. This study has demonstrated that meat qualities of Tan mutton may be assessed by the serum biochemical indices of live Tan sheep. It is necessary to determine slaughter traits, meat texture characteristics and water-holding capacity of meat, which are major indicators for assessing meat and meat products by consumers. [ABSTRACT FROM AUTHOR]

A combined hydroxyl-functionalized and NH 4 Cl-assisted etching strategy is developed to effectively promote the yield of edge-hosted single-atomic Cu-N4 sites. The developed CuSAs@DCSs renders outstanding ORR activity (E onset =1.02 V, E 1/2 = 0.90 V), and excellent stability. CuSAs@DCSs-based Zn-air battery achieves ultralong cycle life and large power density. Rich edge-hosted active sites are responsible for the remarkable ORR performance. [Display omitted] • A hydroxyl-functionalized and NH 4 Cl-assisted etching strategy is developed to promote the yield of edge-hosted Cu-N4 sites. • Rich accessible edge-hosted Cu-N4 sites are responsible for the remarkable ORR performance. • CuSAs@DCSs exhibits extraordinarily ORR activity and excellent stability in both alkaline and acid solution. • CuSAs@DCSs exhibits superb performance when used as air cathode for Zn–air battery. • This strategy can be extended to fabricate other single atoms catalyst with controlled electronic structure. Single-atom electrocatalysts with metal-nitrogen-carbon (M N C SACs) moieties in carbon support display outstanding electrocatalytic performance towards oxygen reduction reaction (ORR) and have received widespread attentions. Only active sites on the edges of pores in carbon support are electrochemically accessible and contribute to ORR. Herein, we report a combined hydroxyl-functionalized and NH 4 Cl-assisted etching strategy to effectively promote the yield of edge-hosted Cu SAs. Thus, well-defined SAs with Cu-N 4 configuration are generated into the defect of carbonaceous nanospheres (CuSAs@DCSs). Impressively, the obtained SACs renders outstanding electrocatalytic ORR activity with onset, half-wave potentials of 1.02 V, 0.90 V, and extremely high stability, which transcends the noble-metals and most of the previously reported catalysts. When used in rechargeable Zn-air batteries, CuSAs@DCSs achieves ultralong cycle life at the large current density of 10 mA cm−2 (over 260 h) with low charge–discharge potential gap. Our study demonstrates that the creation of abundant micropores enriches the electrochemically accessible SAs, which locate at the edge-defects and are responsible for the remarkable ORR performance. This work sheds a facile strategy for designing and developing efficient electrocatalyst for various energy-related electrocatalytic reactions. [ABSTRACT FROM AUTHOR]

Using Cu-CoFe/Co/NC as trifunctional electrocatalysts in alkaline seawater, an overall hydrazine splitting (OHzS) unit is self-powered by a direct hydrazine fuel cell (DHzFC), demonstrating the great potential of Cu-CoFe/Co/NC as trifunctional electrocatalysts toward energy storage and conversion devices. [Display omitted] • Cu-doped CoFe/Co encapsulated by N -doped carbon (Cu-CoFe/Co/NC) is synthesized. • The electronic structure and d-band center of catalyst are regulated. • The catalyst show good ORR, HzOR and HER performance in alkaline seawater. • The catalyst is used into direct hydrazine fuel cell and overall hydrazine splitting. The development of high-performance and robust electrocatalyst suitable for oxygen reduction reaction (ORR), hydrazine oxidation reaction (HzOR), and hydrogen evolution reaction (HER) in seawater still faces huge challenges. In this study, Cu-doped CoFe/Co encapsulated by N -doped carbon (Cu-CoFe/Co/NC) is synthesized via chemical precipitation followed by carbonization method, in which the electronic structure and d-band center of Cu-CoFe/Co/NC are regulated by metal doping and hetero-engineering. The as-synthesized Cu-CoFe/Co/NC exhibit excellent electrocatalytic activity for ORR (E 1/2 = 0.87 V), HzOR (η 10 = 281 mV), and HER (η -10 = 217 mV) in alkaline seawater. Inspiringly, the self-assembled direct hydrazine fuel cell (DHzFC) are used to power overall hydrazine splitting (OHzS) for proof of concept, demonstrating the great potential of Cu-CoFe/Co/NC as trifunctional electrocatalyst toward energy storage and conversion devices. [ABSTRACT FROM AUTHOR]

As a novel visible-light-driven photocatalyst, Yb 3 + /Ho 3 + co-doped Bi 2 WO 6 (Yb 3 + /Ho 3 + -Bi 2 WO 6 ) was synthesized via a simple hydrothermal method and subsequent a calcination process. The as-synthesized Yb 3 + /Ho 3 + -Bi 2 WO 6 samples were characterized by various analytical methods. The BIW-5 (Yb 3 + /Ho 3 + molar ratios is 5) sample showed the highest photocatalytic activity. The RhB was degraded (99.8%) under visible light irradiation in 20 min. The improved photocatalytic activity could be attributed to the efficient energy transfer between Yb 3 + /Ho 3 + and Bi 2 WO 6 via infrared to visible upconversion and the reduced combination rate of photogenerated electron-hole pairs through doping Yb 3 + /Ho 3 + ions. Therefore, this study may provide a better method to obtain stable upconversion photocatalyst with greatly improved activity. [ABSTRACT FROM AUTHOR]

Yb 2 O 3 :Ho 3+ nanocrystalline powders were synthesized through a solid state reaction method. X-ray diffraction analysis and field emission scanning electron microscopy were used to analyze the phase composition and morphology of the powders. Then under the 980 nm excitation of laser diode, the fluorescence of the crystals was studied via a fluorescence spectrometer. The green and red emissions centered on 551 and 668 nm were observed, and the green band dominated the emission spectrum. The effect of the concentration of Ho 3+ on the upconversion luminescence intensity was discussed and the possible upconversion emission mechanism was explained. It indicates that like other metal oxide nanoparticles, Yb 2 O 3 could also be a potential host material for doping to prepare the upconversion phosphor. [ABSTRACT FROM AUTHOR]

The efficient biological treatment of saline wastewater has been limited by the low activities of microorganisms under saline conditions. High salinity poses unbalance osmotic stress across the cell wall and even leads to cell plasmolysis. In this work, we aim to isolate salt-tolerant bacterial strains from activated sludge, and apply them for degrading chemical oxygen demand (COD) of saline organic wastewater. Two salt-tolerant strains were screened and isolated from activated sludge, which was domesticated with salty water for over 300 days. The two strains were identified as Bacillus cereus (strain A) and Bacillus anthracis (strain B) through 16S rRNA sequencing. The degradation characteristics of strain A were explored. The results showed the relative membrane permeability of strain A remained stable under high salt stress, which glycine and proline play an important role to maintain cell osmotic. The protein and soluble sugar amounts of strain were increased by higher salt concentrations. In simulating saline wastewater, the optimum culture temperature, pH, salinity, influent COD concentration and inoculation amount of strain A were 35 °C, 9, 4%, 8000 mg L−1, 6%, respectively. Optimal conditions could provide guidance for the treatment of practical saline wastewater. The linear regression model of each impact factor built based on the result PB experiment revealed that cross-linking time has the most significant influence on COD removal for salt-tolerant strains. It will provide theoretical basis for biological treatment of saline organic wastewater. [ABSTRACT FROM AUTHOR]

A novel diatomite/oyster shell (DS) powder doped polyacrylonitrile composite fiber adsorbent was fabricated via electrospinning technology and anion functionalization (fun -PAN/DS) was carried out with sodium hydroxide and sodium bicarbonate. The influences of different parameters such as solution pH, contact time, temperature and initial concentration on the adsorption of methylene blue (MB) were investigated in batch mode. The adsorption data showed that the removal rate of MB increased from 10.96% to 96.45% with the increase of pH value. The Freundlich isotherm model was found to be best depicting the adsorption of MB on fun -PAN/DS submicron fiber with a maximum capacity of 243.44 mg/g. The pseudo second-order dynamics model (R2 > 0.99) was more suitable for experimental data than other kinetic models. In the summary, fun -PAN/DS fiber with good physicochemical stability is an excellent material to be a high-efficiency adsorbent for removing methylene blue from aqueous solution. Unlabelled Image • Diatomite/oyster shell powder was successfully incorporated into polyacrylonitrile fibers. • Simple functionalization successfully optimizes the adsorption capacity of composite fibers. • fun -PAN/DS composite fibers exhibit excellent adsorption capacity. • Diatomite/oyster shell powder conserve adsorption sites after incorporation into fun -PAN/DS fibers. • Composition of fun -PAN/DS fibers shows a synergistic increase in adsorption of MB from water. [ABSTRACT FROM AUTHOR]

• A series of Tm3+/Yb3+-Bi 2 WO 6 catalysts hydrothermally prepared and characterized. • Tm3+/Yb3+-Bi 2 WO 6 showed excellent optical properties. • Significantly enhanced photocatalytic activity is achieved when degrading RhB. • This study provides a great way to obtain stable photocatalyst. Tm3+ and Yb3+ co-doped Bi 2 WO 6 up-conversion photocatalysts (Tm3+/Yb3+:Bi 2 WO 6) were synthesized via co-precipitation route at different calcination temperatures. Doping Tm3+ and Yb3+ into Bi 2 WO 6 lattice and substituting for the fractional Bi3+ were successfully confirmed by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analysis. The morphology and optical property of the obtained samples were characterized by field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), UV–vis diffuse reflectance spectra (DRS) and up-conversion luminescence spectra (UC-PL). The photocatalytic results revealed that the Tm3+/Yb3+:Bi 2 WO 6 exhibited a much superior photocatalytic activity than the pure Bi 2 WO 6 and commercial Degussa P25 for the degradation of rhodamine B (RhB), and the degradation rate reached 97.6% in 25 min. The effects of Tm3+ and Yb3+ on the photocatalytic activity of Bi 2 WO 6 were studied in detail. The improved photocatalytic activity of Bi 2 WO 6 could be attributed to the efficient energy transfer between Tm3+/Yb3+ and Bi 2 WO 6 via infrared to visible up-conversion and the reduced recombination rate of photogenerated electron-hole pairs through co-doping of Tm3+/Yb3+ on Bi 2 WO 6 nanopaticles. [ABSTRACT FROM AUTHOR]