In this manuscript,the neat epoxy(EP)and functionalized Fe_(3)O_(4)(G-Fe_(3)O_(4))reinforced epoxy(G-Fe_(3)O_(4)/EP)coatings were cured under different temperatures,and the effect of the low curing temperature on the ...In this manuscript,the neat epoxy(EP)and functionalized Fe_(3)O_(4)(G-Fe_(3)O_(4))reinforced epoxy(G-Fe_(3)O_(4)/EP)coatings were cured under different temperatures,and the effect of the low curing temperature on the anticorrosion performance was investigated.The experimental results show that the epoxy-amine ring-open addition reaction mainly exists in the curing process,and the activation energies of the reaction for the two coatings are 55.84 and 53.29 kJ/mol,respectively.For the coatings cured at the low temperature,almost no pores could be detected on the fracture surface,but the presentence of the rough regions reflects the poor curing state.As compared with the samples cured at the high temperature,the anticorrosion performance of the coatings with the low curing temperature is worse,and the decrease rate of the anticorrosion performance is slower,because of the poor curing state and low adhesion obtained at the low temperature.展开更多
[Objective] This study aimed to investigate the effects of different preservative treatments on physiological metabolism and preservation of sweet cherry. [Method] Sweet cherry (Prunus avium var. Summit) was soaked ...[Objective] This study aimed to investigate the effects of different preservative treatments on physiological metabolism and preservation of sweet cherry. [Method] Sweet cherry (Prunus avium var. Summit) was soaked into benziothiazolinone (1 000 ppm), lysozyme (500 ppm), lysozyme (500 ppm) + NPS polysaccharide (5 000 ppm) and water for 5 min, respectively. Non-treated sweet cherry was set as control. All the sweet cherries were then put into 3 mm thick PE bags and preserved at (-0.5±0.5) ℃. [Result] The results showed that the malate dehydrogenase (MDH) activity of benziothiazolinone treatment researched a significant peak on the 14 th d, while the MDH activity of Lysozyme (500 ppm), Lysozyme (500 ppm) + NPS polysaccharide (5 000 ppm) and water treatments began to increase on the 20 th d; the polyphenol oxidase (PPO) activity in various treatments showed a decreasing trend during the experiment, which researched a significant peak on the 14 th d, while that in water treatment was decreased consistently; on the 21 st d, the PPO activity in each treatment increased slowly; the titratable acid (TA) content in preservative treatments was higher than that in both water treatment and control; the soluble solid (SSC) content showed no significant difference between various treatments and between experimental treatment and control; on the 40 th d, the healthy fruit rate in preservative treatments was significantly higher than that in water treatment and control. [Conclusion] Benziothiazolinone, lysozyme and other preservatives show good effects on preservation of sweet cherry; lysozyme treatment can decrease the activity of malate dehydrogenase, maintain the relatively high content of organic acid and significantly improve the healthy fruit rate within a certain period of time.展开更多
The nano-size metal oxide was prepared by the single-disperse technique on liquid phase, and formed sol dusters, its uniform film was covered on the surface of cashmere fibers by coating, and it had good oil repellenc...The nano-size metal oxide was prepared by the single-disperse technique on liquid phase, and formed sol dusters, its uniform film was covered on the surface of cashmere fibers by coating, and it had good oil repellency and water repellency. The results of IR(infrared) Spectrometer analysis revealed: The nano material combines through the strong bonds with the surface of cashmere fibers by the live groups. These analyses by SEM techniques showed that the nano material was distributed on the fiber surface even, and the nano material formed the strong peak of the regular crystal phase structure using the X-Ray Diffractometry (XRD) to analysis the fabric. The optimum techniques were selected by a series of experiments, coated cashmere fabric not only has preserved original properties of softness and comfort, but also has good properties of Bi-repellency function. Therefore, the technique will have potential appfication in engineers.展开更多
The water extract of dry mycelium ofPenicillium chrysogenum (DME) was used to induce resistance in Virginia tobacco plants against Phtophthora parasitica var. nicotianae. Results showed that the efficacy of DME in c...The water extract of dry mycelium ofPenicillium chrysogenum (DME) was used to induce resistance in Virginia tobacco plants against Phtophthora parasitica var. nicotianae. Results showed that the efficacy of DME in controlling black shank disease depended on both DME solution concentration and its' treatment methodology. Soil application of 1.5-5% DME 72 hr before inoculation with Phtophthora parasitica vat. nicotianae provided highly significant protection against black shank, relative to the control without DME treatment. Optimized tobacco plant treatment with 2.5% DME significantly increased peroxidase (POD) and polyphenol oxidase (PPO) activity levels in the upper leaf sections of the tobacco plants. DME had no direct antifungal activity on the growth of Phtophthora parasitica var. nicotianae in vitro, suggesting that disease control with DME treatment resulted from the induced propagation of natural defense mechanisms in the tobacco plants.展开更多
Heavy metals pose a potential threat to aquatic organisms. In this study, a static-renewal acute toxicity test was conducted to investigate the effects of cadmium on the antioxidant defense systems (both enzymatic an...Heavy metals pose a potential threat to aquatic organisms. In this study, a static-renewal acute toxicity test was conducted to investigate the effects of cadmium on the antioxidant defense systems (both enzymatic and non-enzymatic) and lipid peroxidaton in liver and gill tissues of juvenile GIFT tilapia Oreochromis niloticus. After 8 days of exposure to Cd (0, 0.016, 0.08, 0.4 and 2 mg/L), livers accumulated significantly more Cd than gills. Catalase (CAT), superoxide dismutase (SOD) and glutathione S-transferase (GST) activities were stimulated only at the highest concentration tested (2 mg/L). Glutathione peroxidase (GPx) activity was stimulated in the gill while inhibited in the liver, these alternations in gill and liver showed a strong relationship with Cd levels in these tissues. This may indicate either a tissue-specific response of GPx to Cd or, most probably, a hormetic effect of Cd on GPx. Cd increased GSH levels and decreased the ratio GSSG/GSH in fish livers at 2 mg/L. Cd exposure resulted in an elevated level of MDA in the livers of fish at 2 mg/L, indicating that Cd caused lipid peroxidation. Taken together, the results demonstrated that Cd altered the enzymatic and non-enzymatic defensive systems and caused lipid peroxidation in O. niloticus at relatively high concentrations (compared to environmentally relevant concentrations). In addition, the results implied that O. niloticus could tolerate high level of Cd in sites polluted by Cd.展开更多
NiO-In2O3 composite nanofibers are synthesized via electrospinning and calcining techniques. Micro-sensors are fabricated by sputtering Pt electrodes on Si chips to form sensor substrates, and then spinning the NiO-In...NiO-In2O3 composite nanofibers are synthesized via electrospinning and calcining techniques. Micro-sensors are fabricated by sputtering Pt electrodes on Si chips to form sensor substrates, and then spinning the NiO-In2O3 composite nanofibers onto the sensor substrate surface. The as-fabricated micro-sensors exhibit excellent H2S sensing properties at room temperature. The sensi- tivity of the micro-sensors is up to 6 when the sensors are exposed to 3 μL/L HzS, and the corresponding response and recovery times are 14 and 22 s, respectively. The micro-sensors also exhibit high selectivity and good stability. Especially, the micro-sensors can operate at various humidity conditions. The sensitivity of the micro-sensors is 3.8 to 3 μL/L HzS at 75% relative humidity. These characteristics make the micro-sensors good candidates for practical H2S sensors with high performance.展开更多
基金Project(U2106216)supported by the National Natural Science Foundation of China。
文摘In this manuscript,the neat epoxy(EP)and functionalized Fe_(3)O_(4)(G-Fe_(3)O_(4))reinforced epoxy(G-Fe_(3)O_(4)/EP)coatings were cured under different temperatures,and the effect of the low curing temperature on the anticorrosion performance was investigated.The experimental results show that the epoxy-amine ring-open addition reaction mainly exists in the curing process,and the activation energies of the reaction for the two coatings are 55.84 and 53.29 kJ/mol,respectively.For the coatings cured at the low temperature,almost no pores could be detected on the fracture surface,but the presentence of the rough regions reflects the poor curing state.As compared with the samples cured at the high temperature,the anticorrosion performance of the coatings with the low curing temperature is worse,and the decrease rate of the anticorrosion performance is slower,because of the poor curing state and low adhesion obtained at the low temperature.
基金Supported by Fund from Technology Bureau of Wuhan City (201120722215-2)~~
文摘[Objective] This study aimed to investigate the effects of different preservative treatments on physiological metabolism and preservation of sweet cherry. [Method] Sweet cherry (Prunus avium var. Summit) was soaked into benziothiazolinone (1 000 ppm), lysozyme (500 ppm), lysozyme (500 ppm) + NPS polysaccharide (5 000 ppm) and water for 5 min, respectively. Non-treated sweet cherry was set as control. All the sweet cherries were then put into 3 mm thick PE bags and preserved at (-0.5±0.5) ℃. [Result] The results showed that the malate dehydrogenase (MDH) activity of benziothiazolinone treatment researched a significant peak on the 14 th d, while the MDH activity of Lysozyme (500 ppm), Lysozyme (500 ppm) + NPS polysaccharide (5 000 ppm) and water treatments began to increase on the 20 th d; the polyphenol oxidase (PPO) activity in various treatments showed a decreasing trend during the experiment, which researched a significant peak on the 14 th d, while that in water treatment was decreased consistently; on the 21 st d, the PPO activity in each treatment increased slowly; the titratable acid (TA) content in preservative treatments was higher than that in both water treatment and control; the soluble solid (SSC) content showed no significant difference between various treatments and between experimental treatment and control; on the 40 th d, the healthy fruit rate in preservative treatments was significantly higher than that in water treatment and control. [Conclusion] Benziothiazolinone, lysozyme and other preservatives show good effects on preservation of sweet cherry; lysozyme treatment can decrease the activity of malate dehydrogenase, maintain the relatively high content of organic acid and significantly improve the healthy fruit rate within a certain period of time.
文摘The nano-size metal oxide was prepared by the single-disperse technique on liquid phase, and formed sol dusters, its uniform film was covered on the surface of cashmere fibers by coating, and it had good oil repellency and water repellency. The results of IR(infrared) Spectrometer analysis revealed: The nano material combines through the strong bonds with the surface of cashmere fibers by the live groups. These analyses by SEM techniques showed that the nano material was distributed on the fiber surface even, and the nano material formed the strong peak of the regular crystal phase structure using the X-Ray Diffractometry (XRD) to analysis the fabric. The optimum techniques were selected by a series of experiments, coated cashmere fabric not only has preserved original properties of softness and comfort, but also has good properties of Bi-repellency function. Therefore, the technique will have potential appfication in engineers.
文摘The water extract of dry mycelium ofPenicillium chrysogenum (DME) was used to induce resistance in Virginia tobacco plants against Phtophthora parasitica var. nicotianae. Results showed that the efficacy of DME in controlling black shank disease depended on both DME solution concentration and its' treatment methodology. Soil application of 1.5-5% DME 72 hr before inoculation with Phtophthora parasitica vat. nicotianae provided highly significant protection against black shank, relative to the control without DME treatment. Optimized tobacco plant treatment with 2.5% DME significantly increased peroxidase (POD) and polyphenol oxidase (PPO) activity levels in the upper leaf sections of the tobacco plants. DME had no direct antifungal activity on the growth of Phtophthora parasitica var. nicotianae in vitro, suggesting that disease control with DME treatment resulted from the induced propagation of natural defense mechanisms in the tobacco plants.
文摘Heavy metals pose a potential threat to aquatic organisms. In this study, a static-renewal acute toxicity test was conducted to investigate the effects of cadmium on the antioxidant defense systems (both enzymatic and non-enzymatic) and lipid peroxidaton in liver and gill tissues of juvenile GIFT tilapia Oreochromis niloticus. After 8 days of exposure to Cd (0, 0.016, 0.08, 0.4 and 2 mg/L), livers accumulated significantly more Cd than gills. Catalase (CAT), superoxide dismutase (SOD) and glutathione S-transferase (GST) activities were stimulated only at the highest concentration tested (2 mg/L). Glutathione peroxidase (GPx) activity was stimulated in the gill while inhibited in the liver, these alternations in gill and liver showed a strong relationship with Cd levels in these tissues. This may indicate either a tissue-specific response of GPx to Cd or, most probably, a hormetic effect of Cd on GPx. Cd increased GSH levels and decreased the ratio GSSG/GSH in fish livers at 2 mg/L. Cd exposure resulted in an elevated level of MDA in the livers of fish at 2 mg/L, indicating that Cd caused lipid peroxidation. Taken together, the results demonstrated that Cd altered the enzymatic and non-enzymatic defensive systems and caused lipid peroxidation in O. niloticus at relatively high concentrations (compared to environmentally relevant concentrations). In addition, the results implied that O. niloticus could tolerate high level of Cd in sites polluted by Cd.
基金supported by the Special Fund for Agroscientific Research in the Public Interest of China(200903023)the Earmarked Fund for Modern Agroindustry Technology Research System of China([2011]3)the Guangdong Agricultural Mechanization Research Project([2010]605)
文摘NiO-In2O3 composite nanofibers are synthesized via electrospinning and calcining techniques. Micro-sensors are fabricated by sputtering Pt electrodes on Si chips to form sensor substrates, and then spinning the NiO-In2O3 composite nanofibers onto the sensor substrate surface. The as-fabricated micro-sensors exhibit excellent H2S sensing properties at room temperature. The sensi- tivity of the micro-sensors is up to 6 when the sensors are exposed to 3 μL/L HzS, and the corresponding response and recovery times are 14 and 22 s, respectively. The micro-sensors also exhibit high selectivity and good stability. Especially, the micro-sensors can operate at various humidity conditions. The sensitivity of the micro-sensors is 3.8 to 3 μL/L HzS at 75% relative humidity. These characteristics make the micro-sensors good candidates for practical H2S sensors with high performance.