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Excessive zinc (Zn) uptake is toxic to both plants and animals. 24-Epibrassinolide (EBL), a plant steroid hormone, plays a pivotal role in regulating plant resistance to various stresses. In this s...

The effects of foliar application of 24-epibrassinolide (EBR) on chlorophyll content, oxidative damage, and antioxidant capacity in eggplant (Solanum melongena L.) seedlings during a short-term chilling stress and subsequent recovery were investigated. The eggplant seedlings pretreated with 0.1 μM EBR were exposed to 5 °C for 12 h in the dark and then recovered under a normal temperature for another 12 h. The results show that EBR alleviated a chilling-induced oxidative stress reflected by a decrease in malondialdehyde and H2O2 content, O2 ·− production rate, and an increase in chlorophyll content and activities of superoxide dismutase, guaicol peroxidase, and catalase. The EBR pretreatment also promoted activities of ascorbate peroxidase, glutathione reductase, dehydroascorbate reductase, as well as the accumulation of ascorbic acid (AsA) and glutathione (GSH) involved in the AsA-GSH cycle. Moreover, after the12 h recovery, EBR plus chilling treated leaves showed no significant changes in content of MDA and chlorophyll a, lower reactive oxygen species (ROS) content, and greater activities of AsA-GSH cycle enzymes than in seedlings only chilled. The results suggest that EBR alleviated an oxidative damage caused by the dark chilling stress and accelerated a recovery rate mainly through increasing the ROS scavenging system including the AsA-GSH cycle.

SummaryBrassinosteroids (BRs) have been implicated in the responses of plants to various environmental stresses.To explore the mechanism(s) of BRs in the tolerance of plants to low temperatures, 24-epibrassinolide (EBR)-induced changes in chlorophyll concentrations, gas exchange parameters, chlorophyll fluorescence, and anti-oxidant defence systems in eggplant (Solanum melongena L.) were studied under chilling stress conditions. Seedlings were exposed to 10°C/5°C (day/night) chilling temperatures for 8 d, with or without a single spray of 0.1 ?M EBR applied 24 h beforehand.The EBR treatment partially overcame the inhibition of growth caused by 8 d of chilling stress.The application of EBR to chilled seedlings had a significant effect on photosynthesis, as reflected by increases in the concentrations of chlorophyll a, chlorophyll b, and total chlorophyll, the net photosynthetic rate (Pn), stomatal conductance (gs), the quantum efficiency of PSII (Fv/Fm), the efficiency of the excitation capture of open PSI...

In this paper, the carburising process of steel foil was simulated by numerical method and the carbon transfer coefficient β at the workpiece surface was calculated with the conventional formula for the steel foil carburising test. The results indicated that foil thickness, carburising time and carbon diffusion coefficient in foil apparently affect the calculated carbon transfer coefficient, which always has a smaller value than the preset β value (the true value) and decreases with decreasing carbon diffusion coefficient. This paper suggests that the conventional formula is applicable only when carbon diffusion coefficient in foil is close to infinity; otherwise, the calculated β has obvious error and consequently, gives false information about the influences of other test factors. We propose a new calculation method based on the analytical solution of the diffusion equation during steel foil carburising and a supplementary test, with which the calculated β coefficient is close to the true value,...

This study was carried out to understand the mechanism of protection of plants under cold stress by exogenous 24-epibrassinolide (EBR). The eggplant (Solanum melongena L.) seedlings were pretreated with five concentrations of EBR (0, 0.05, 0.1, 0.2 and 0.4 °M) and then exposed to day/night temperatures of 10/5 °C for 8 d. The results show that EBR, especially 0.1 °M EBR, dramatically alleviated growth suppression and a decrease in chlorophyll content and photosynthetic rate caused by the cold stress. In addition, EBR also decreased malondialdehyde content and O2·− production rate induced by the cold stress, and increased the activities of superoxide dismutase, guaiacol peroxidase, catalase, and ascorbate peroxidase, and proline content. The results of the present study suggest that exogenous EBR could improve cold tolerance of eggplant by regulating photosynthesis and antioxidative systems.

Electroforming has been applied in the fabrication of a mold. However, its lower microhardness has prevented its wider usage in general plastics and optical mold making. In this paper, CeO2 nanoparticles is first added to the bath to improve the microhardness of the electroformed microprism mold. Compared with microprism pure nickel mold, the microhardness and the wear resistance of the microprism Ni-CeO2 nanocomposite mold were significantly improved. The maximum microhardness of 530HV was observed in the nanocomposite deposits obtained at the current density of 1 Adm−2, and the microhardness of pure nickel is approximately 291HV. Finally, a microprism Ni-CeO2 nanocomposite mold was successfully electroformed.

The effects of exogenous 24-epibrassinolide (EBR) on the growth, oxidative damage, antioxidant system and ion contents in eggplant (Solanum melongena L.) seedlings under salt stress were investigated. Eggplant seedlings were exposed to 90 mM NaCl with 0, 0.025, 0.05, 0.10 and 0.20 mg dm−3 EBR for 10 d. EBR, especially at concentration 0.05 mg dm−3, alleviated growth suppression caused by NaCl stress, decreased electrolyte leakage, superoxide production and content of malondialdehyde and H2O2 in NaCl-treated plants. EBR also increased activities of superoxide dismutase, guaiacol peroxidase, catalase and ascorbate peroxidase and the contents of ascorbic acid and reduced glutathione. Furthermore, we also found that Na+, Cl− contents were decreased, K+, Ca2+ contents and K+/Na+, Ca2+/Na+ ratios were increased in the presence of EBR under salt stress.

The microstructure and electromagnetic properties of FeCoB-SiO 2 thin films which were deposited on different substrates (silicon, glass and Mylar) by using magnetron sputtering were studied. X-Ray Diffraction revealed that FeCo nanocrystalline only precipitated in FeCoB-SiO 2 thin films on silicon and glass substrates, and the FeCoB-SiO 2 films on Mylar substrate were amorphous. The surface images obtained by atomic microscopy (AFM) indicated that films on Mylar substrate with biggest particle size (about 120–150 nm), and agglomerated particle was discovered. The static electromagnetic properties, including resistivity and saturation magnetization for the films on different substrates, had also been investigated. The films sputtered on glass showed highest resistivity (2140 μΩcm) and a biggest saturation magnetization (4πMs = 13 kG).

The composites of In nanoparticles embedded in Al-based amorphous matrix were synthesized. As the content of In increases, the average size of In nanoparticles increases. The melting behaviors of embedded In nanoparticles were investigated, indicating that the melting temperature is suppressed, and the smaller the size is, the lower the melting temperature is. It is confirmed by comparing the differential scanning calorimetry curves with those of the size distribution. The size dependent melting behaviors of nanoparticles were discussed with the thermodynamic model.