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With the gradual depletion of the earth’s resources and people’s attention to environmental issues, the access of renewable energy has been paid more and more attention by countries around the world. Wind is one of the pollution-free energy sources, and wind power generation is forming a boom in the world, because wind power generation does not need to use fuel, nor does it produce radiation or air pollution. The power of wind power generation is characterized by volatility and intermittence. When there is disturbance in the system, the wind farm is likely to oscillate and challenge the stability of the power grid. Therefore, the wind turbine generator must be connected to SVG system to realize dynamic reactive power compensation function, so as to ensure the stability of its operation in case of fault. In addition, the cause of wind turbine oscillation needs to be analyzed in detail to ensure its stability.

Ascorbic acid is a nutritional small molecule essential to human life activities and health, playing a vital role in many physiological processes. Fresh fruits and beverages can provide abundant AA to maintain human metabolic balance. Therefore, it is of great significance to develop a nanomaterial with superior nanozyme activity for rapid and convenient detection of ascorbic acid (AA) in fruits and beverages. Herein, a dual-signal sensing platform based on UV-vis absorption and test strip chromaticity for the quantitative determination of AA is presented. The sensing platform is based on the horseradish peroxidase-like activity of Ni 3 V 2 O 8 nanoflowers, which catalyzes the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) by hydrogen peroxide to the blue oxide TMB (ox TMB). The ox TMB produced by the oxidation has a characteristic absorption peak at 650 nm. In the presence of AA, the blue ox TMB is reduced to colorless TMB, and the quantitative detection of AA can be achieved by detecting the decrease in intensity of the absorption peak by UV-Vis spectrophotometry. Under the optimal experimental conditions, the sensing platform exhibited excellent sensitivity and selectivity. A wide linear range of 0.1 μM to 40 μM with a detection limit of 0.032 μM was obtained. The linear equation is Δ A = 0.02513 c + 0.1164 with a correlation coefficient of 0.9979. It showed excellent properties in the detection of real samples of fruit juices and beverages, meanwhile, a method for the rapid detection of AA based on chromaticity change of test strips was constructed with high sensitivity and convenience. The linearity range for the ascorbic acid was 1-50 μM with LOD of 0.42 μM. The developed sensing platform has the capability to quickly and accurately detect ascorbic acid (AA) in fresh fruits and beverages. This proposed method offers a new and promising approach for the rapid and cost-effective detection of ascorbic acid, which has a wide range of potential applications., Competing Interests: The authors declare there are no conflicts of interest regarding the publication of this paper., (This journal is © The Royal Society of Chemistry.)

The conventional flue gas treatment technologies require high capital investments and chemical costs, which limit their application in industrial sectors. This study developed a sulfur-cycling technology to integrate sulfide production by biological sulfur reduction and simultaneous catalytic desulfurization and denitrification with H 2 S (H 2 S-SCDD) for flue gas treatment and sulfur recovery. In a packed bed reactor, high-rate sulfide production (1.63 ± 0.16 kg S/m 3 -d) from biological sulfur reduction was achieved using organics in wastewater as electron donors at pH around 5.8. 93% of sulfide in wastewater was stripped out as H 2 S g , which can be a low-cost reducing agent in the H 2 S-SCDD process. Over 90% of both SO 2 and NO were removed by the H 2 S-SCDD process under the test conditions, resulting in the formation of sulfur. 88% of the input S (H 2 S g and SO 2 ) were recovered as octasulfur with high purity. Besides partial recycling to produce biogenic sulfide, excessive sulfur can be obtained as a sellable product. The integrated sulfur-cycling technology is a chemical-saving and even profitable solution to the flue gas treatment in industrial sectors with wastewater available.