Adenosma bracteosum and Vitex negundo are natural sources of methoxylated flavonoids. Little is known about the α‐glucosidase inhibition of multi‐methoxylated flavonoid derivatives. Eighteen natural ...flavonoids were isolated from A. bracteosum and V. negundo. Seven halogenated derivatives were synthesized. Their chemical structures were elucidated by extensive NMR analysis and high‐resolution mass spectroscopy as well as comparisons in literature. All compounds were evaluated for their α‐glucosidase inhibition. Most compounds showed good activity with IC50 values ranging from 16.7 to 421.8 μM. 6,8‐Dibromocatechin was the most active compound with an IC50 value of 16.7 μM. A molecular docking study was conducted, indicating that those compounds are potent α‐glucosidase inhibitors.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
A highly active and stable boron-promoted catalyst was successfully prepared by using the sequential incipient wetness impregnation technique and examined for methane bi-reforming reaction. The ...initial investigation found that the NiO and B2O3 particles were dispersed on the outer surface of the high surface area SBA-15 support. In addition, the catalytic activity was increased linearly with the tested reaction temperature due to the endothermic nature of the reaction. In fact, the catalyst achieved the CH4 conversion and H2/CO molar ratio of approximately 67.3% and 2.7, respectively at 1073 K. The resulting product ratio is highly suitable for downstream Fischer-Tropsch (FT) synthesis. The B-promoted catalyst showed the lowest degree of catalyst deactivation (4%) at 1023 K. Additionally, the XPS measurements unveiled that the boron facilitates the adsorption of CO2 by donating electrons to the neighbouring Ni cluster and thus improved its catalytic performance. Furthermore, Raman and XRD analysis revealed that the boron promotion on 10%Ni/SBA-15 could prevent the reoxidation and deposition of carbonaceous species.
•Catalytic performance for B-promoted catalyst increased linearly with CSCRM reaction temperature.•CH4 conversion and H2/CO of 70% and 2.7, respectively were achieved at 1073 K.•Catalyst showed excellent resistance to carbon formation and reoxidation during 24 h.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The speed of urbanization—industrialization in Vietnam is increasing, which helps to boost the economy and at the same time create great environmental pressure. Industrial wastewater from production ...processes is always abundant and discharged continuously every day with diverse pollution components. Wastewater treatment of by simple and low-cost methods has been concerned. In this study, constructed wetland (CW) model using the
Brachiaria mutica
has been researched to evaluate the performance of Horizontal subsurface flow (HSSF) CW in treating industrial effluents. The model built with dimensions is 1.2 m × 0.4 m × 0.6 m and operated under 4 research organic load rates respectively 40; 60; 80; 100 kgCOD/ha.day. Average treatment efficiency of pollution parameters through study is COD 93.86%, T–N 97.46%, T–P 91.12%, TSS 83.07%, BOD
5
97.72%. The output concentration values of the pollution parameters are smaller than the allowable values in column A QCVN 40: 2011/ BTNMT. The results of this study will be the premise to find solutions for industrial wastewater treatment with easy to operate and environmentally friendly. The process of industrial wastewater treatment using CW planning
B. mutica
is simple and efficient. The success of this work is possible to expand research on wastewater treatment capacity of CW planning
B. mutica
with different kinds of wastewater such as domestic wastewater, livestock wastewater, medical wastewater.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The novel nanostructured Ti0.9Ir0.1O2 acting as a potential catalyst support for Pt in fuel cell applications was easily synthesized by means of a facile and simple low-temperature hydrothermal ...process without using any surfactants and further heat treatment. Interestingly, even in low iridium doping concentration, the Ti0.9Ir0.1O2 support possessed the high electronic conductivity of 0.016 S/cm, which was ∼105 times as high as pure TiO2 (4.15 × 10−7 S/cm), suggesting the efficient doping of iridium into TiO2 lattice. Furthermore, the modified chemical reduction route utilized to prepare the 20 wt % Pt/Ti0.9Ir0.1O2 electrocatalyst exhibited the good anchoring and uniform distribution of Pt nanoparticles (NPs) (∼3 nm) over Ti0.9Ir0.1O2 surface and thus eventually resulted in the high electrochemical surface area (∼85.08 m2/gPt) compared to that of the commercial 20 wt % Pt/C (E-TEK) catalyst (∼69.21 m2/gPt). The cyclic voltammetry results in the methanol media revealed that the 20 wt % Pt/Ti0.9Ir0.1O2 displayed the superior electrocatalytic activity compared to the 20 wt % Pt/C (E-TEK) catalyst towards the methanol electro-oxidation. For instance, the 20 wt % Pt/Ti0.9Ir0.1O2 catalyst possessed the higher oxidation current density (∼28.8 mA/cm2), the lower onset potential (∼0.12 V) and the higher If/Ib ratio in comparison with the commercial 20 wt % Pt/C (E-TEK) catalysts. It is worth noting that the chronoamperometry results also indicated that the 20 wt % Pt/Ti0.9Ir0.1O2 exhibited higher durability than the commercial 20 wt % Pt/C (E-TEK) catalyst. Beside introducing novel Ti0.9Ir0.1O2 material, these results also offer a pathway of exploring the low dopants content of TixIr1-xO2 material to serve as a good catalyst support for many fuel cell applications.
•A facile green synthetic route for the preparation of the novel Ti0.9Ir0.1O2.•The Ti0.9Ir0.1O2 possessed high electronic conductivity with the low doping concentration.•Pt/Ti0.9Ir0.1O2 has low onset potential for methanol oxidation reaction.•Pt/Ti0.9Ir0.1O2 demonstrates high activity and durability for methanol oxidation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Ibuprofen contamination from water sources has been increasingly alarming due to its environmentally accumulative retention; however, the strategies for ibuprofen-containing water treatment are still ...an enormous challenge. Herein, we described the utilization of metal-organic frameworks MIL-53(Fe) (MIL = Materials of Institute Lavoisier) for the adsorption of ibuprofen in synthetic solution. Firstly, the MIL-53(Fe) was solvothemally synthesized and then characterized using the X-ray diffraction and Fourier-transform infrared spectroscopy techniques. The optimization of ibuprofen adsorption over MIL-53(Fe) was performed with three independent variables including ibuprofen concentration (1.6–18.4 mg/L), adsorbent dosage (0.16–1.84 g/L), and pH (2.6–9.4) according to the experimental design from response surface methodology. Under the optimized conditions, more than 80% of ibuprofen could be eliminated from water, indicating the promising potential of the MIL-53(Fe) material for treatment of this drug. Kinetic and isotherm models also were used to elucidate the chemisorption and monolayer behavior mechanisms of ibuprofen over MIL-53(Fe).
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FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
For the first time, a novel Pt catalyst supported on mesoporous Ti0.7W0.3O2 nanoparticles, which exhibited superior advantages such as high conductivity (0.022 S/cm), large specific surface area ...(201.481 m2/g) and homogeneous morphology with 9 nm spherical-like particles, was prepared successfully via the rapid microwave-assisted polyol route. It is found that uniform 3 nm spherical-like Pt nano-forms were adhered homogeneous on the surface of Ti0.7W0.3O2. Intriguingly, the electrochemical surface area of Pt catalyst supported on mesoporous Ti0.7W0.3O2 was found to be around 90.05 m2/gPt, which is profoundly higher than ECSA value obtained from Pt/C (E-TEK) catalyst. Furthermore, as for methanol oxidation reaction measurement, the If/Ib ratio of the 20 wt % Pt/Ti0.7W0.3O2 catalyst was found to be approximately 2.33, which 2.5-folds higher than that of the commercial Pt/C (E-TEK) catalyst. Importantly, the chronoamperometry data also revealed that the 20 wt % Pt/Ti0.7W0.3O2 catalyst possessed the higher durability than the commercial 20 wt % Pt/C (E-TEK) catalyst. In addition, the successful synthesis of the 20 wt % Pt/Ti0.7W0.3O2 catalyst not only offers an attractive catalyst for fuel cell using methanol but also opens application potentials for solar cells, as well as biosensors.
•Mesoporous Ti0.7W0.3O2 support was simply prepared via facile solvothermal route.•Mesoporous Ti0.7W0.3O2 exhibited a large surface area and high electrical conductivity.•Pt/Ti0.7W0.3O2 was prepared via a fast and facile microwave-assisted polyol route.•Pt/Ti0.7W0.3O2 catalyst displayed good methanol electro-oxidation.•Pt/Ti0.7W0.3O2 catalyst possessed superior durability for methanol oxidation reaction.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Direct methanol fuel cells (DMFCs) have attracted considerable scientific interest because of their ease of operation and implementation; however, poor electrocatalytic activity and durability are ...the main hindrances for their commercial feasibility. Moreover, the deactivation of active Pt sites, due to the coverage of CO-like species during the electrochemical oxidation reaction, significantly degrades the electrochemical surface area (ECSA). In the present work, stable Pt-supported tin-modified indium oxide (ITO) was synthesized as a promising electrocatalyst towards the methanol oxidation reaction (MOR) in DMFCs. It was found that 20 wt% Pt/ITO yielded much higher current density (∼0.71 mA/cm2) than the state-of-the-art carbon-supported Pt (E-TEK) electrocatalyst. Furthermore, the If/Ib ratio, which featured the CO tolerance of the electrocatalyst, of 20 wt% Pt/ITO was found to be ∼1.42, which is ∼1.5-fold higher than that of 20 wt% Pt/C (E-TEK). Chronoamperometry results indicated that 20 wt% Pt/ITO manifested much higher stability than 20 wt% Pt/C (E-TEK).
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
High cost and poor durability of Pt-based electrocatalysts are the main challenges for future commercialization of direct ethanol fuel cells (DEFCs). In the present work, a stable and effective ...Pt/Ti0.8W0.2O2 electrocatalyst toward ethanol electrooxidation reactions (EORs) was prepared by utilizing the attributes of noncarbon catalyst supports and low Pt loading. The 18.5 wt % Pt/Ti0.8W0.2O2 electrocatalyst was successfully fabricated through a simple and rapid microwave-assisted polyol route (ethylene glycol was used as a reducing agent). In comparison with a conventional 20 wt % Pt/C electrocatalyst, the as-prepared 18.5 wt % Pt/Ti0.8W0.2O2 electrocatalyst resulted in much lower onset potential, higher If/Ib value, and superior stability toward EOR, which can be ascribed to the synergistic effect between Pt nanocatalyst and the Ti0.8W0.2O2 catalyst support. Therefore, these findings imply that 18.5 wt % Pt/Ti0.8W0.2O2 is a promising anodic electrocatalyst and possesses the ability to replace Pt/C electrocatalysts in the future.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
To overcome the disadvantages of commercial carbonaceous catalysts in direct methanol fuel cells (DMFCs), novel Pt/Ti1–xIrxO2 catalysts are fabricated in this study. Simultaneously, the influence of ...the Ir composition in the support on the electrocatalytic activities and physicochemical properties of Pt/Ti1–xIrxO2 catalysts is also evaluated. Ti1–xIrxO2 materials with the tunable Ir composition (x = 0.1, 0.2, 0.3) synthesized via a simple and green hydrothermal route exhibited much higher electrical conductivity and surface area than the undoped TiO2. Furthermore, the well-distributed Pt nanoparticles (NPs) with small sizes (∼3 nm) over supports were obtained by using a modified chemical reduction route. Electrochemical results revealed that a series of 20 wt. % Pt/Ti1–xIrxO2 catalysts exhibited superior durability and electrochemical activity toward the methanol oxidation reaction to the commercial 20 wt. % Pt/C (E-TEK) catalyst. According to these results, Ti1–xIrxO2 materials seem to be very promising as a stable catalyst support in the harsh medium of DMFCs.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Microwave-assisted hydro-distillation (MAHD) is preferred to traditional extraction methods due to shorter extraction time, the inability of volatile components to be damaged or decomposed which in ...turn improve the efficiency and quality of essential oils. In this research, we investigated the parameters that affect the extraction of lemongrass oil process by MAHD method and compare with those of hydro-distillation (HD) method. Four parameters were identified which are: raw material size, raw material to water ratio, extraction time and microwave power. The results show that the optimum condition for determining the lemongrass essential oil content is 20 mm in the 90 min extraction time with a microwave power of 450 W at raw material to water ratio of 1:3 (g/mL). When compared to the HD method, we found that the yield lemongrass oil of MAHD method is 0.35% on 90 min and the yield of HD method is 0.2% on 360 min. The quality of oil samples at different extraction method was evaluated by determining their chemical constituents through GC-MS. The highest identified component is Citral with 93.28% for MAHD, while the HD was 83.85%. Therefore, MAHD method is highly efficient and shorten the time needed for the extraction of essential oils.
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