This study aims to synthesize and evaluate the photocatalytic activity of bismuth terephthalate material (Bi-BDC) synthesized by solvothermal (ST) and microwave-assisted solvothermal (MW) methods. ...Differences in the crystal structure and crystal shape were assessed by analytical methods such as X-ray diffraction (XRD), scanning electron microscope (SEM), Fourier transform infrared (FT-IR) spectrum, X-ray photoelectron spectroscopy (XPS), N
2
adsorption/desorption, Raman spectrum, and thermal gravimetric analysis (TGA). From XRD, IR, Raman, and XPS results, the fully crystallized Bi-BDC materials were achieved regardless of the preparation router. Bi-BDC-MW exhibited spherical-like morphologies, producing between stacked lamellar, while Bi-BDC-ST method exhibited a heterogeneous structure. The TGA data indicated that Bi-BDC is thermally stable up to 300 °C, suggesting the excellent thermal stability of Bi-BDC. The surface area and pore volume of Bi-BDC-MW (18 m
2
/g and 85 × 10
−3
cm
3
/g) are higher than those of Bi-BDC-ST (16 m
2
/g and 52 × 10
−3
cm
3
/g), which is due to its well-defined lamellar microstructure and homogeneity of the crystals. Compared to Bi-BDC-ST, Bi-BDC-MW has a higher value in the content of oxygen vacancy. Moreover, the photocatalytic efficiency of Bi-BDC-MW was significantly higher than that of Bi-BDC-ST, in which 99.44% rhodamine B (RhB) is removed after 360 min of irradiation. The improved photocatalytic efficiency of Bi-BDC-MW is ascribed to the morphology, specific surface area, and oxygen defects, which exhibited the good separation of electrons and holes, as confirmed by the photoluminescence (PL). The results should open a new approach to enhancing the photocatalytic activity of bismuth terephthalate materials.
African swine fever is one of the most dangerous diseases of swine. We confirmed the 2019 outbreak in Vietnam by real-time reverse transcription PCR. The causative strain belonged to p72 genotype II ...and was 100% identical with viruses isolated in China (2018) and Georgia (2007). International prevention and control collaboration is needed.
Summary
Azole‐resistant environmental Aspergillus fumigatus presents a threat to public health but the extent of this threat in Southeast Asia is poorly described. We conducted environmental ...surveillance in the Mekong Delta region of Vietnam, collecting air and ground samples across key land‐use types, and determined antifungal susceptibilities of Aspergillus section Fumigati (ASF) isolates and azole concentrations in soils. Of 119 ASF isolates, 55% were resistant (or non‐wild type) to itraconazole, 65% to posaconazole and 50% to voriconazole. Azole resistance was more frequent in A. fumigatus sensu stricto isolates (95%) than other ASF species (32%). Resistant isolates and agricultural azole residues were overrepresented in samples from cultivated land. cyp51A gene sequence analysis showed 38/56 resistant A. fumigatus sensu stricto isolates carried known resistance mutations, with TR34/L98H most frequent (34/38).
The blossom of renewable energy worldwide and its uncertain nature have driven the need for a more intelligent power system with the deep integration of smart power electronics. The smart inverter is ...one of the most critical components for the optimal operation of Smart Grid. However, due to the deep information and communication technology (ICT) infrastructure implementation that most inverter-based smart power systems tend to have, they are vulnerable to severe external threats such as cyberattacks by hackers. This paper presents a comprehensive review of the system structure and vulnerabilities of typical inverter-based power system with distributed energy resources (DERs) integration, nature of several types of cyberattacks, state-of-the-art defense strategies including several detection and mitigation techniques, and an overview and comparison of testbed and simulation tools applicable for cyber-physical research. Finally, challenges, unsolved problems, and future direction of the field are discussed and concluded at the end of the journal. This paper provides an all-inclusive survey at the state of the art smart grid cybersecurity research and paves the path for potential research topics in the future.
Bismuth vanadate, BiVO
4
, is a visible-light response semiconductor for photocatalysis applications such as organic pollutants degradation, oxygen production and carbon dioxide reduction. However, ...as a single-phase photocatalyst, BiVO
4
efficiency is limited by the unpreferable recombination of the photoexcited electron (e
−
) and hole (h
+
). Thus, strategies have been designed to enhance the photocatalytic efficiency by promoting the separation of electrons and holes. This can be done by controling the morphology and crystallographic facets of BiVO
4
, and by building p–n junction photocatalytic systems with a combination of n-type semiconductors (BiVO
4
) and p-type semiconductors or a monoclinic–tetragonal heterostructure of BiVO
4
. In particular, a direct p–n junction photocatalytic system with tetragonal zircon-structured BiVO
4
(t-z) and monoclinic scheelite-structured BiVO
4
(m-s) combination has recently attracted attention. Here we review the synthesis of the monoclinic–tetragonal heterostructured BiVO
4
photocatalyst (m–t BiVO
4
) by calcination, hydrothermal, microwave-assisted hydrothermal and solvothermal methods. m–t BiVO
4
formation and the transmission phase between t-z and m-s are controlled by the calcining temperature, precursor pH, metal doping content, type of solvent, implementation of precursors and reaction conditions. We discuss m–t BiVO
4
crystal structure, optical characteristics and photocatalytic principles. Successful formation of BiVO
4
crystals with a m-s/t-z heterostructure is based on data from X-ray diffraction (XRD), Raman and ultraviolet–visible diffuse reflectance spectroscopy (UV–Vis DRS). In the m–t BiVO
4
heterostructure, a direct p–n junction photocatalytic system is established. When this system is exposed to visible light, the electrons in the conduction band of m-s BiVO
4
, a n-type semiconductor, migrate easily to the conduction band of t-z BiVO
4
, while the holes on valence band of t-z BiVO
4
, a p-type semiconductor, move to the valence band of m-s BiVO
4
through an internal electric field. As a result, the e
−
/h
+
charge carriers are spatially separated.
The flame‐retardant low‐density polyethylene (LDPE) composites loading aluminum hydroxide (ATH), red phosphorus (RP), and expandable graphite (EG) were successfully prepared. The flame retardancy, ...the thermo‐oxidative stability, and the mechanical property of the composites were investigated. The synergistic effect of ATH, RP, and EG on the flame‐retardant property and thermal behavior of LDPE were observed. The limiting oxygen index value of LDPE significantly increased from 17.1% to 25.4% upon the incorporation of 15 wt.% of the mixture of three fillers with ATH:RP:EG mass ratio of 1:1:1; and this composite achieved the V‐0 classification of the UL94 vertical burning test. The thermogravimetric analysis of this composite under air atmosphere revealed that its residue weight remained 27.89% at 900°C. Furthermore, the results of tension tests indicated that the surface modification of ATH by magnesium stearate and RP by poly(methylhydrosiloxane) noticeably improved the tensile strength and the elongation of the composite.
In this paper, by revisiting coderivative calculus rules for convex multifunctions in finite-dimensional spaces, we derive formulae for estimating/computing the basic subdifferential and the ...coderivative of the efficient point multifunction of parametric convex vector optimization problems. These results are then applied to a broad class of conventional convex vector optimization problems with the presence of operator constraints and equilibrium ones. Examples are also designed to analyze and illustrate the obtained results.
In this study, the operation parameters of a partial nitrification process (PN) treating saline wastewater were optimized using the Box–Behnken design via the response surface methodology (BBD-RSM). ...A novel strategy based on the control of the carbon/nitrogen ratio (C/N), alkalinity/ammonia ratio (K/A), and salinity in three stages was used to achieve PN in a sequence batch reactor. The results demonstrated that a high and stable PN was completed after 50 d with an ammonia removal efficiency (ARE) of 98.37 % and nitrite accumulation rate (NAR) of 85.93 %. Next, BBD-RSM was applied, where ARE and NAR were the responses. The highest responses from the confirmation experiment were 99.9 % ± 0.04 and 95.25 % ± 0.32 when the optimum C/N, K/A, and salinity were identified as 0.84, 2, and 5.5 (g/L), respectively. The results were higher than those for the nonoptimized reactor. The developed regression model adequately forecasts the PN performance under optimal conditions. Therefore, this study provides a promising strategy for controlling the PN process and shows how the BBD-RSM model can improve the PN performance.
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•A synthetic strategy was used for partial nitrification in saline wastewater.•This strategy controlled the C/N ratio, K/A ratio, and salinity instead of DO.•Ammonia oxidation and nitrite accumulation were optimized by the BBD-RSM model.•Optimal C/N and K/A ratios and salinity were 0.84, 2, and 5.5 g/L, respectively.•ARE = 99.9 % ± 0.04 and NAR = 95.25 % ± 0.32 occurred under optimal conditions.
In this study, a nanohybrid based on montmorillonite (oMMT2) was prepared through a two‐step method using Arquad MCB‐80 and 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO) as intercalation ...agents. The nanohybrid exhibited a basal spacing of 31.5 Å, which contained approximately 12.3% of Arquad MCB‐80 and 31.6% of DOPO. Various amount of oMMT2 nanohybrid was incorporated into a flame‐retardant polyethylene system containing aluminum trihydroxide and red phosphorus with a constant total additive content of 20 wt%. The dispersibility of oMMT2 in the composite matrix was evaluated by energy dispersive x‐ray mapping and x‐ray diffraction analyses. At a content of 3 wt% in the nanocomposite, oMMT2 showed a highly exfoliated state, while at a 5% content, a partially exfoliated and intercalated state was observed. A synergistic flame‐retardant effect between the nanohybrid and the mixture of aluminum trihydroxide and red phosphorus was found. The nanocomposite loading 3 wt% oMMT2 demonstrated the best flame retardancy, achieving a V‐0 rating of the vertical burning test with a limiting oxygen index of 27.6%. Moreover, the addition of the low oMMT2 contents (≤3 wt%) improved the mechanical properties of the flame‐retardant composite.
Preparation process of DOPO‐containing organoclay and its synergistic flame retardant mechanism with aluminum hydroxide and red phosphorus
Aquaculture is increasing at the global scale, and beneficial reuse of wastewater is becoming crucial in some regions. Here we selected a unique tertiary treatment system for study over a one-year ...period. This experimental ecosystem-based approach to effluent management included a treated wastewater pond (TWP), which receives 100% effluent from a wastewater treatment plant, and an aquaculture pond (AP) that receives treated water from the TWP for fish production. We examined the fate of a wide range of pharmaceutically active compounds (PhACs) in this TWP-AP system and a control pond fed by river water using traditional grab sampling and passive samplers. We then employed probabilistic approaches to examine exposure hazards. Telmisartan, carbamazepine, diclofenac and venlafaxine, exceeded ecotoxicological predicted no effect concentrations in influent wastewater to the TWP, but these water quality hazards were consistently reduced following treatment in the TWP-AP system. In addition, both grab and passive sampling approaches resulted in similar occurrence patterns of studied compounds, which highlights the potential of POCIS use for water monitoring. Based on the approach taken here, the TWP-AP system appears useful as a tertiary treatment step to reduce PhACs and decrease ecotoxicological and antibiotic resistance water quality hazards prior to beneficial reuse in aquaculture.
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•We studied pharmaceutical fate in a tertiary treatment pond system over one year.•37 analytes were present in all collected samples over the year-long period.•Pharmaceutical patterns in passive samplers were similar to grab samples.•We employed a probabilistic approach to examine water quality hazards.•Treatment by this pond system decreased water quality hazards of most analytes.
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