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In this work, a vibration was applied in the preparation of the Mg/Al bimetal by a novel compound casting in order to improve the mechanical properties of the Mg/Al bimetal, and the effect of the vibration on the interfacial microstructure and mechanical properties of the Mg/Al bimetal was investigated. The results indicated that the vibration had a significant effect on the interfacial microstructure and mechanical properties of the Mg/Al bimetal, but it did not change the phase compositions of the interface, which was composed of layer I (Al 3 Mg 2 +Mg 2 Si), layer II (Al 12 Mg 17 +Mg 2 Si) and layer III (Al 12 Mg 17 /δ-Mg). Without vibration, the Mg 2 Si phase with a needle-like morphology mainly aggregated in the layer II of the interface. After the application of the vibration, the SEM and EBSD analysis results showed that the Mg 2 Si and Al 3 Mg 2 phases in the interface were obviously refined, and the distribution of the Mg 2 Si became more uniform, due to the strong forced convection of the molten metal resulting from the vibration. The TEM analysis indicated that the interface between the Al 3 Mg 2 and Mg 2 Si phases was non-coherent, suggesting the Mg 2 Si particles cannot act as a heterogeneous nucleation base during the solidification process of the interface. Compared to the Mg/Al bimetal without vibration, the shear strength of the Mg/Al bimetal with vibration increased by about 50% from 31.7 MPa on average to 47.5 MPa, and the hardness of the layer I of the interface increased, and the hardness of the layer III decreased. The fracture surface transformed from a flat fracture morphology without vibration to an irregular zigzag fracture morphology. [ABSTRACT FROM AUTHOR]

In this paper, a Ni coating was deposited on the surface of the A356 aluminum alloy by high velocity oxygen fuel spraying to improve the performance of the AZ91D magnesium/A356 aluminum bimetal prepared by a compound casting. The effects of the Ni coating as well as its thickness on microstructure and mechanical properties of the AZ91D/A356 bimetal were systematically researched for the first time. Results demonstrated that the Ni coating and its thickness had a significant effect on the interfacial phase compositions and mechanical properties of the AZ91D/A356 bimetal. The 10µm's Ni coating cannot prevent the generation of the Al-Mg intermetallic compounds (IMCs) at the interface zone of the AZ91D/A356 bimetal, while the Ni coating with the thickness of 45 µm and 190 µm can avoid the formation of the Al-Mg IMCs. When the Ni coating was 45 µm, the Ni coating disappeared and transformed into Mg-Mg 2 Ni eutectic structures+Ni 2 Mg 3 Al particles at the interface zone. With a thickness of 190µm's Ni coating, part of the Ni coating remained and the interface layer was composed of the Mg-Mg 2 Ni eutectic structures+ Ni 2 Mg 3 Al particles, Mg 2 Ni layer, Ni solid solution (SS) layer, Al 3 Ni 2 layer, Al 3 Ni layer and sporadic Al 3 Ni+Al-Al 3 Ni eutectic structures from AZ91D side to A356 side in sequence. The interface layer consisting of the Mg-Ni and Al-Ni IMCs obtained with the Ni coating had an obvious lower hardness than the Al-Mg IMCs. The shear strength of the AZ91D/A356 bimetal with a Ni coating of 45 µm thickness enhanced 41.4% in comparison with that of the bimetal without Ni coating, and the fracture of the bimetal with 45µm's Ni coating occurred between the Mg matrix and the interface layer with a mixture of brittle fracture and ductile fracture. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pseudomonas sp. G16 was isolated with nitrification-denitrification ability. • Efficient removal of inorganic nitrogen at 15℃-30℃ under aerobic conditions. • No accumulation of NO 2 –-N was detected during nitrogen removal. • The nitrogen removal rate of immobilized pellets was increased by about 20%. From the aerobic pond of the farm, the Pseudomonas sp. G16 was screened and isolated, which was confirmed to exhibit heterotrophic nitrification and aerobic denitrification. The removal rates of Ammonia (100 mg/L), nitrate (120 mg/L), and nitrite (100 mg/L) by the strain were 94.13%, 92.62%, and 85.67%, and the nitrogen metabolism pathway of strain G16 was analyzed by whole genome sequencing combined with its nitrification-denitrification intermediate products, it was found that the strain had independent nitrification-denitrification ability and no nitrite accumulation. Under the conditions of carbon source of sodium succinate hexahydrate, C/N ratio of 15, pH of 7.5, temperature of 15 °C, and DO of 210 rpm, strain G16 showed excellent denitrification performance. Strain G16 was prepared into biochar-based immobilized bacterial particles, which successfully improved its nitrogen removal efficiency and stability. Therefore, the application of strain G16 in the field of real wastewater treatment has very necessary research value. [ABSTRACT FROM AUTHOR]

Designing a highly-active electro-Fenton (EF) catalytic membrane without the additional chemicals and iron sludge formation was a challenge for antibiotics treatment. In this study, we constructed Fe/N co-doping biochar (Fe-g-C 3 N 4 /biochar) based ultrafiltration membranes for degradation of tetracycline (a common antibiotic) and membrane fouling control under electro-assistance. The results showed that membranes presented high electro-Fenton catalytic activity because the presence of rich oxygen functional groups (high C–O/C O ratio) and nitrogen species (pyridinic N and pyrrolic N) promoted H 2 O 2 generation and accelerated Fe(III)/Fe(II) cycle. Moreover, H 3 PO 4 activation of biochar endowed the EF catalytic membrane with higher electrocatalytic activity, while it was opposite using biochar with higher pyrolysis temperature (600–700 °C). In particular, owing to the oxidative degradation by electro-generated •OH and •O 2 −, Fe-g-C 3 N 4 /ABC-600/Graphite/PVDF (600 represented the pyrolysis temperature) membrane presented 100% tetracycline removal within 0.749 min of residence time, excellent self-cleaning performance (flux recovery = 100%) at neutral pH and low energy consumption (0.199 W h/L) for the reclamation of synthetic municipal wastewater effluent. In addition, membrane self-cleaning mechanism was closely related to the synergy between partial mineralization and reduced fouling potential of foulants. Besides, the EF membrane also exhibited good reusability and stability, which was promising to apply in antibiotics removal. [Display omitted] • High-active electro-Fenton membrane was prepared with Fe/N co-doping biochar. • The electro-Fenton membrane can quickly remove antibiotics in water at neutral pH. • Membrane performance can be easily modulated by controlling the biochar structure. • The electro-Fenton membrane enabled excellent self-cleaning ability and stability. [ABSTRACT FROM AUTHOR]

• Defective UiO-66 based UF anodic membrane was fabricated for water reclamation. • The fabricated membrane has superior antibiotic removal and self-cleaning property. • New insights into the self-cleaning mechanism of anodic membrane were proposed. • The excellent electrochemical stability ensured the long-term membrane operation. In order to resolve the poor antibiotics rejection and serious fouling of ultrafiltration (UF) membrane during municipal wastewater reclamation, a novel anodic membrane (defective UiO-66 (D-UiO-66)/Graphite/Polyvinylidene fluoride (PVDF)) with high pure water flux (596.1 L• h −1• m −2•bar−1) was fabricated by incorporating defective zirconium based metal-organic framework (D-UiO-66) and conductive graphite particles into PVDF matrix and applied in the coupling of electro-oxidation and membrane filtration process. Compared to the other anodic membranes (i.e., Graphite/PVDF and UiO-66/Graphite/PVDF), D-UiO-66/Graphite/PVDF possesses superior anti-fouling and self-cleaning abilities (flux recovery=100%, model foulant: bovine serum albumin) in both intermittent and continuous supply of electric field under current density of 0.01 mA/cm2; moreover, efficient antibiotics (tetracycline, norfloxacin, tylosin and sulfamethoxazole) removal (> 96.6%) and bactericidal efficiency against E. coli and S. aureus (100%) were achieved simultaneously without the addition of chemical reagents due to the higher electrocatalytic activity of anodic membrane for oxidation of pollutants by •OH and •O 2 – free radicals. Three degradation pathways of antibiotics were proposed and the self-cleaning mechanism of membrane was dominated by the synergy of the partial mineralization and the reduced fouling potential of foulants after oxidation as revealed by the increase in hydrophilicity, and decrease in negative charge and molecular weight. The fabricated membrane also presents excellent electrochemical stability, separation and self-cleaning performance for treatment of municipal secondary effluent during long-term filtration with low electric energy consumption, which is promising in wastewater reclamation. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: As an important part of economical society, colleges and universities have been shouldering the important task of education, science research and social service. In this paper, a detailed investigation in the form of questionnaire was carried out for the energy consumption of colleges and universities in Guangdong Province, including electricity, water, gas and cooling energy consumption from 2006 to 2010. The energy meter reading modes, energy conversation investment amount and energy-efficiency retrofit work were also reported and analyzed. Furthermore, as can be concluded from the survey, there exists great difference in per unit energy consumption between different types of universities classified by schools’ discipline, nature and level, which would be taken into account when the energy consumption evaluation indexes system is established. Although energy-saving measures at Guangdong's colleges and universities bear fruit, Guangdong's colleges and universities still have great potential of energy conservation and emission reduction by Conservation-oriented campus construction, and the government should increase funding and improve economic policy to encourage and support energy saving for colleges and universities. [Copyright &y& Elsevier]