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Enhancing the stability of Ni Fe-layered double hydroxide nanosheet array for alkaline seawater oxidation by Ce doping
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作者 Yongchao Yao Shengjun Sun +14 位作者 Hui Zhang Zixiao Li Chaoxin Yang Zhengwei Cai Xun He Kai Dong Yonglan Luo Yan Wang Yuchun Ren Qian Liu Dongdong Zheng Weihua Zhuang Bo Tang Xuping Sun Wenchuang(Walter)Hu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期306-312,共7页
Electrocatalytic hydrogen production from seawater holds enormous promise for clean energy generation.Nevertheless,the direct electrolysis of seawater encounters significant challenges due to poor anodic stability cau... Electrocatalytic hydrogen production from seawater holds enormous promise for clean energy generation.Nevertheless,the direct electrolysis of seawater encounters significant challenges due to poor anodic stability caused by detrimental chlorine chemistry.Herein,we present our recent discovery that the incorporation of Ce into Ni Fe layered double hydroxide nanosheet array on Ni foam(Ce-Ni Fe LDH/NF)emerges as a robust electrocatalyst for seawater oxidation.During the seawater oxidation process,CeO_(2)is generated,effectively repelling Cl^(-)and inhibiting the formation of Cl O-,resulting in a notable enhancement in the oxidation activity and stability of alkaline seawater.The prepared Ce-Ni Fe LDH/NF requires only overpotential of 390 m V to achieve the current density of 1 A cm^(-2),while maintaining long-term stability for 500 h,outperforming the performance of Ni Fe LDH/NF(430 m V,150 h)by a significant margin.This study highlights the effectiveness of a Ce-doping strategy in augmenting the activity and stability of materials based on Ni Fe LDH in seawater electrolysis for oxygen evolution. 展开更多
关键词 Ce doping NiFe layered double hydroxide Seawater oxidation Electrocatalysis Cl^(-) repulsion
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Ca and Sr co-doping induced oxygen vacancies in 3DOM La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)catalysts for boosting low-temperature oxidative coupling of methane
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作者 Tongtong Wu Yuechang Wei +5 位作者 Jing Xiong Yitao Yang Zhenpeng Wang Dawei Han Zhen Zhao Jian Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期331-344,共14页
It is urgent to develop catalysts with application potential for oxidative coupling of methane(OCM)at relatively lower temperature.Herein,three-dimensional ordered macro porous(3 DOM)La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)(... It is urgent to develop catalysts with application potential for oxidative coupling of methane(OCM)at relatively lower temperature.Herein,three-dimensional ordered macro porous(3 DOM)La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)(A_(2)B_(2)O_(7)-type)catalysts with disordered defective cubic fluorite phased structure were successfully prepared by a colloidal crystal template method.3DOM structure promotes the accessibility of the gaseous reactants(O2and CH4)to the active sites.The co-doping of Ca and Sr ions in La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)catalysts improved the formation of oxygen vacancies,thereby leading to increased density of surface-active oxygen species(O_(2)^(-))for the activation of CH4and the formation of C2products(C2H6and C2H4).3DOM La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)catalysts exhibit high catalytic activity for OCM at low temperature.3DOM La1.7Sr0.3Ce1.7Ca0.3O7-δcatalyst with the highest density of O_(2)^(-)species exhibited the highest catalytic activity for low-temperature OCM,i.e.,its CH4conversion,selectivity and yield of C2products at 650℃are 32.2%,66.1%and 21.3%,respectively.The mechanism was proposed that the increase in surface oxygen vacancies induced by the co-doping of Ca and Sr ions boosts the key step of C-H bond breaking and C-C bond coupling in catalyzing low-temperature OCM.It is meaningful for the development of the low-temperature and high-efficient catalysts for OCM reaction in practical application. 展开更多
关键词 3DOM catalysts Ca ions Sr ions Low-temperature oxidative couplingof methane Oxygen vacancies O_(2)^(-) species
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Modulation of the in vitro Oxidative Stress and Erythrocyte Cell Membrane Integrity Using Aqueous, Hydroethanolic and Ethanolic Stem-Barks Extracts of Greenwayodendron suaveolens (Engl. & Diels) Verdc
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作者 Patrick Hervé Diboue Betote Moustapha Gambo Abdoulaye +6 位作者 Francis Ngolsou Esther Del Florence Ndedi Moni Adeline Sabine Fanta Yadang Fidel Castro Lah Weyepe Gabriel A. Agbor Nga Nnanga Maximilienne Ascension Nyegue 《Pharmacology & Pharmacy》 2024年第3期39-61,共23页
Pneumonia, a respiratory infection induces acute or chronic inflammation, characterized by increased activity of lymphocytes and neutrophils, thus generating oxygen-free radicals that decrease the endogenous antioxida... Pneumonia, a respiratory infection induces acute or chronic inflammation, characterized by increased activity of lymphocytes and neutrophils, thus generating oxygen-free radicals that decrease the endogenous antioxidants defence system. The aim of this experimental study focused on the capacity of nontoxic aqueous, hydroethanolic and ethanolic extracts of Greenwayodendron suaveolens (Engl. & Diels) Verdc. subsp. suaveolens to regulate free reactive species and protein inflammation generated by infectious disease. The phytochemical screenings of G. suaveolens extracts were carried out according to precipitation and colorimetric methods. The total antioxidant and flavonoid contents were determined by the Folin-Ciocalteu and Aluminium Chloride ethanolic methods. The efficiency of G. suaveolens extracts on free radicals was evaluated using DPPH<sup>•</sup>, ABTS<sup>+•</sup>, and FRAP methods. The anti-inflammatory properties of extracts were evaluated according to in vitro protein (BSA) denaturation, Proteinase Inhibitory Action, and Red Blood Cell Membrane stabilization assays. The G. suaveolens aqueous, hydroethanolic and ethanolic extracts were used for the acute toxicity assessment according to the OECD protocol. The obtained results showed the presence of flavonoids, phenols, polyphenols, tannins, anthocyanins, alkaloids, terpenoids, and sterols as secondary metabolites families in G. suaveolens extracts. The highest contents of total antioxidants and flavonoids were highlighted in the hydroethanolic extract. However, it’s the G. suaveolens aqueous extract that showed the best free radical DPPH<sup>•</sup> and ABTS<sup>+•</sup> scavenging activities (SC<sub>50</sub>) of 11.06 μg/mL and 15.16 μg/mL respectively. The highest ferric-reducing activity was found in G. suaveolens ethanolic extract with 866.23 μg EGA/mg of dry weight. The hydroethanolic extract has shown a high anti-inflammatory activity through BSA denaturation and erythrocyte membrane haemolysis with inhibitory concentrations 50 (IC<sub>50</sub>) of 48.63 and 59.22 μg/mL respectively. In contrast, proteinase inhibitory activity revealed a better potential of IC<sub>50</sub> (34.19 μg/mL) for the ethanolic extract. In oral acute toxicity, all treated groups revealed neither mortality nor any significant alteration in behaviour and locomotion. The lethal dose 50 (LD<sub>50</sub>) of G. suaveolens extracts was >5000 mg/kg. These results suggest that G. suaveolens stem-barks extracts may serve as therapeutic sources to prevent inflammation induced by oxidative stress, an important feature of infectious diseases. 展开更多
关键词 Greenwayodendron suaveolens Secondary Metabolites oxidative Stress antioxidant Activity anti-Inflammatory Properties and Oral Acute Toxicity
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ANTI-HYPOXIA AND ANTI-OXIDATION EFFECTS OF AMINOPHYLLINE ON HUMAN WITH ACUTE HIGH-ALTITUDE EXPOSURE 被引量:8
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作者 Bo Yang Guang-yi Wang +3 位作者 Bin Chen Rong-bin Qin Si Lang Zha Xi Lian Chen 《Chinese Medical Sciences Journal》 CAS CSCD 2007年第1期62-65,共4页
Objective To investigate the anti-hypoxia and anti-oxidation effects of aminophylline on human with acute high- altitude exposure. Methods Totally 100 young male army members newly recruited from Sichuan province (400... Objective To investigate the anti-hypoxia and anti-oxidation effects of aminophylline on human with acute high- altitude exposure. Methods Totally 100 young male army members newly recruited from Sichuan province (400 meters above sea level) were enrolled. They were randomly divided into two groups: 50 in aminophylline group (A group) and 50 in control group (C group). A group and C group orally took aminophylline and placebo respectively for 10 days, 7 days before entering Lhasa (3 658 meters above sea level) by air and 3 days after it. Several parameters were measured at three time points: before drug taken, 7 days after drug taken, and 3 days after ascending high altitude. These parameters included serum levels of nitric oxide (NO), superoxide dismutase (SOD), catalase (CAT), hydrogen dioxide (H2O2), lactic acid (LA), as well as arterial oxygen saturation (SO2), arterial oxygen partial pressure (PaO2), and arterial carbon dioxide partial pressure (PaCO2). Statistical analysis was conducted to compare the difference between two groups with Stata 7.0 software system. Results There were no statistical differences between groups in hypoxia and oxidation indicators before and after drug taken in plain area. Three days after ascending high altitude, the serum levels of SOD, CAT, H2O2, LA, PaCO2 increased in both groups, yet to a much larger degree in C group than A group (P<0.01); and NO, SO2, PaO2 decreased more markedly in C group (P<0.05 for NO, P<0.0001 for SO2 and PaO2). Conclusion Aminophylline has significant anti-hypoxia and anti-oxidation effects at high altitude. 展开更多
关键词 缺氧 抗氧化作用 氨茶碱 治疗
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Preparation technology and anti-corrosion performances of black ceramic coatings formed by micro-arc oxidation on aluminum alloys 被引量:7
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作者 CHEN Ling HAN Jing YU Shengxue 《Rare Metals》 SCIE EI CAS CSCD 2006年第z2期146-149,共4页
In order to prepare ornamental and anti-corrosive coating on aluminum alloys, preparation technology of black micro-arc ceramic coatings on Al alloys in silicate based electrolyte was studied. The influence of content... In order to prepare ornamental and anti-corrosive coating on aluminum alloys, preparation technology of black micro-arc ceramic coatings on Al alloys in silicate based electrolyte was studied. The influence of content of Na2WO4 and combination additive in solution on the performance of black ceramic coatings was studied; the anticorrosion performances of black ceramic coatings were evaluated through whole-immersion test and electrochemical method in 3.5% NaCl solution at different pH value; SEM and XRD were used to analyze the surface morphology and phase constitutes of the black ceramic coatings. Experimental results indicated that, without combination additives, with the increasing of Na2WO4 content in the electrolyte, ceramic coating became darker and thicker, but the color was not black; after adding combination additive, the coating turned to be black; the black ceramic coating was multi-hole form in surface. There was a small quantity of tungsten existing in the black ceramic coating beside α-Al2O3 phase and β-Al2O3 phase. And aluminum alloy with black ceramic coating exhibited excellent anti-corrosion property in acid, basic and neutral 3.5% NaCl solution. 展开更多
关键词 aluminum alloy micro-arc oxidation BLACK coating anti-CORROSION performance
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A Study on Anti-oxidative Activity of Soybean Peptideswith Linoleic Acid Peroxidation Systems 被引量:13
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作者 XU Li LI Hong-mei +3 位作者 HUANG Yi-bing WANG Hua NIE Guang-jun ZHANG Xue-zhong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2006年第2期205-208,共4页
Soybean bioactive peptides(SBPs) were prepared from the isolated soybean protein by proteolysis with an alkaline protease, alcalase, at 50℃ and pH = 8.0. The dependence of hydrolysis time on hydrolysis degree and m... Soybean bioactive peptides(SBPs) were prepared from the isolated soybean protein by proteolysis with an alkaline protease, alcalase, at 50℃ and pH = 8.0. The dependence of hydrolysis time on hydrolysis degree and molecular weight distribution were examined. The hydrolysate was fractionated on a Sephadex G-25 column and the anti-oxidative activities of the fractions were detected by the method of pyrogallol auto-oxidation. The average chain length of soybean peptides that have anti-oxidative activity was estimated to be about 7. The anti-oxidative properties of the soy- bean peptide were also studied by using linoleic acid peroxidation systems. The optimal condition of the peroxidation system was set up, Vc/Cu^2 + as the inducer at pH = 7.4 and 25 ℃. In addition, soybean peptides show higher antioxidative activity compared with GSH. 展开更多
关键词 Soybean bioactive peptides anti-oxidative activity Linoleic acid peroxidation system
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Preparation and Properties of Anti-oxidation Inorganic Nano-coating for Low Carbon Steel at an Elevated Temperature 被引量:3
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作者 魏连启 叶树峰 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2006年第4期48-52,共5页
A new kind of anti-oxidation inorganic nano-coating for the common low carbon steel was prepared. It included magnesite mineral, metallurgic dust and silicate adhesive as the main raw materials. The nano-coating could... A new kind of anti-oxidation inorganic nano-coating for the common low carbon steel was prepared. It included magnesite mineral, metallurgic dust and silicate adhesive as the main raw materials. The nano-coating could be sprayed directly onto the low carbon steel slab even though with hot surface as far as under 1000 ℃ . And at the same time, a compact thin nano-film was formed, and the film would inhibit the oxygen into the interface of the steel body and decrease the loss of weight because of oxidation. The loss was decreased by about 60% or more. The properties and mechanism of oxidation resistance of the coating were discussed through XRD, TG-DTA and SEM. The experimental results show that many reactions would happen among the companents of the coating and then many microspheres with the size of 80- 100nm generated in the system. By using the heat of the steel body, the silicate adhesive would interact with the microspheres, and the other components of the coating would be soft and sintered so that when the coating was sprayed onto the suface of the steel slab , the intact and compact film could be formed and adhesive with the steel body. Besides the special properties of anti- oxidation, the coating could prevent the volatilization of microelement in the steel such as silicate and carbon at a high temperature. So it can improve the quality and output of steel with this new kind of nano-coating. 展开更多
关键词 low carbon steel anti-oxidation nano-coating oxidation loss metallurgh dust
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DESTRUCTION OF ANTI-SCALANTS IN RO CONCENTRATES BY ELECTROCHEMICAL OXIDATION 被引量:4
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作者 杨庆峰 马紫峰 +1 位作者 HASSON David SEMIAT Raphael 《化工学报》 EI CAS CSCD 北大核心 2004年第2期339-340,共2页
关键词 反渗透浓缩液 阻垢剂 电化学氧化 脱盐处理 锌电极
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Effects of Waterborne Cu and Cd on Anti-oxidative Response, Lipid Peroxidation and Heavy Metals Accumulation in Abalone Haliotis discus hannai Ino 被引量:1
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作者 LEI Yanju ZHANG Wenbing +3 位作者 XU Wei ZHANG Yanjiao ZHOU Huihui MAI Kangsen 《Journal of Ocean University of China》 SCIE CAS 2015年第3期511-521,共11页
The aim of this study was to compare the effects of waterborne copper(Cu) and cadmium(Cd) on survival, anti-oxidative response, lipid peroxidation and metal accumulation in abalone Haliotis discus hannai. Experimental... The aim of this study was to compare the effects of waterborne copper(Cu) and cadmium(Cd) on survival, anti-oxidative response, lipid peroxidation and metal accumulation in abalone Haliotis discus hannai. Experimental animals(initial weight: 7.49 g ± 0.01 g) were exposed to graded concentrations of waterborne Cu(0.02, 0.04, 0.06, 0.08 mg L-1) or Cd(0.025, 0.05, 0.25, 0.5mg L-1) for 28 days, respectively. Activities of the anti-oxidative enzymes(catalase, CAT; superoxide dismutase, SOD; glutathione peroxidases, GPx; glutathione S-transferase, GST), contents of the reduced glutathione(GSH) and malondiadehyde(MDA) in the hepatopancreas, and metal accumulation in hepatopancreas and muscles were analyzed after 0, 1, 3, 6, 10, 15, 21, 28 days of metal exposure, respectively. Results showed that 0.04 mg L-1, 0.06 mg L-1 and 0.08 mg L-1 Cu caused 100% death of abalone on the 21 st, 10 th and 6th day, respectively. However, no dead abalone was found during the 28-day waterborne Cd exposure at all experimental concentrations. Generally, activities of SOD and GST in hepatopancreas under all Cu concentrations followed a decrease trend as the exposure time prolonged. However, these activities were firstly increased and then decreased to the control level and increased again during Cd exposure. Activities of CAT in all Cu exposure treatments were higher than those in the control. These activities were firstly increased and then decreased to the control level and increased again during Cd exposure. Contents of MDA in hepatopancreas in all Cu treatments significantly increased first and then decreased to the control level. However, the MDA contents in hepatopancreas were not significantly changed during the 28-day Cd exposure. The metals accumulation in both hepatopancreas and muscles of abalone significantly increased with the increase of waterborne metals concentration and exposure time. These results indicated that H. discus hannai has a positive anti-oxidative defense against Cu or Cd. In conclusion, anti-oxidative mechanism in abalone to resist waterborne Cu did not follow the same pattern as that for waterborne Cd. 展开更多
关键词 重金属积累 镉(CD) 抗氧化反应 皱纹盘鲍 脂质过氧化 铜浓度 抗水性 鲍鱼
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Neuroprotective mechanisms of rutin for spinal cord injury through anti-oxidation and anti-inflammation and inhibition of p38 mitogen activated protein kinase pathway 被引量:9
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作者 Hong-liang Song Xiang Zhang +5 位作者 Wen-zhao Wang Rong-han Liu Kai Zhao Ming-yuan Liu Wei-ming Gong Bin Ning 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第1期128-134,共7页
Rutin has anti-inflammatory, antioxidant, anti-viral, anti-tumor and immune regulatory effects. However, the neuroprotective effects of rutin in spinal cord injury are unknown. The p38 mitogen activated protein kinase... Rutin has anti-inflammatory, antioxidant, anti-viral, anti-tumor and immune regulatory effects. However, the neuroprotective effects of rutin in spinal cord injury are unknown. The p38 mitogen activated protein kinase (p38 MAPK) pathway is the most important member of the MAPK family that controls inflammation. We assumed that the mechanism of rutin in the repair of spinal cord injury is associated with the inhibition of p38 MAPK pathway. Allen’s method was used to establish a rat model of spinal cord injury. The rat model was intraperitoneally injected with rutin (30 mg/kg) for 3 days. After treatment with rutin, Basso, Beattie and Bresnahan locomotor function scores increased. Water content, tumor necrosis factor alpha, interleukin 1 beta, and interleukin 6 levels, p38 MAPK protein expression and caspase-3 and -9 activities in T8–9 spinal cord decreased. Oxidative stress related markers superoxide dismutase and glutathione peroxidase levels increased in peripheral blood. Rutin exerts neuroprotective effect through anti-oxidation, anti-inflammation, anti-apoptosis and inhibition of p38 MAPK pathway. 展开更多
关键词 nerve regeneration spinal cord injury RUTIN oxidative stress antioxidant anti-INFLAMMATION p38 mitogen activated protein kinase pathway anti-APOPTOSIS caspase-3 caspase-9 neural regeneration
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Microstructure of a Mo-Si-C-N multi-layered anti-oxidation coating on carbon/carbon composites by fused slurry 被引量:1
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作者 LAI Zhonghong MENG Songhe +1 位作者 ZHU Jingchuan JEON Jaeho 《Rare Metals》 SCIE EI CAS CSCD 2009年第5期460-464,共5页
A Mo-Si-C-N multi-layered anti-oxidation coating was in-situ fabricated by introducing nitrogen atmosphere during the fused sintering of Mo-Si slurry pre-layer on carbon/carbon composites. The phase composition and mi... A Mo-Si-C-N multi-layered anti-oxidation coating was in-situ fabricated by introducing nitrogen atmosphere during the fused sintering of Mo-Si slurry pre-layer on carbon/carbon composites. The phase composition and microstructure of the Mo-Si-C-N coating were characterized by X-ray diffractometry, optical microscopy, scanning electron microscopy with energy dispersive spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy. The Mo-Si-C-N coating exhibited a three-layered structure. Besides the MoSi2/Si main-layer and the SiC bonding-layer, a surface layer of about 10 μm in thickness was synthesized on the coating surface. The surface layer mainly consisted of SiC nanowires and contained some Si3N4 and Si phases. SiC nanowires of 10 to 200 nm in diameter presented a terrace and distortion structure. Transmission electron microscopy indicated that the SiC nanowires grew along the preferred 〈111〉 direction. During oxidation test, SiC nanowires transmuted into SiO2 glass, which can play an important role in improving the oxidation resistance of C/C composites. 展开更多
关键词 C/C composites COATING MICROSTRUCTURES anti-oxidation
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Preparation and Anti-oxidation Mechanism of Mullite/Yttrium Silicate Coatings on C/SiC Composites 被引量:3
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作者 马青松 cai lihui 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2016年第6期1284-1288,共5页
In order to enhance the oxidation resistance of C/Si C composites, mullite/yttrium silicate coatings were fabricated on C/Si C composites through dip-coating route. Al_2O_3-SiO_2 sol with high solid content was select... In order to enhance the oxidation resistance of C/Si C composites, mullite/yttrium silicate coatings were fabricated on C/Si C composites through dip-coating route. Al_2O_3-SiO_2 sol with high solid content was selected as the raw material for mullite and "silicone resin + Y_2O_3 powder" slurry was used to synthesize yttrium silicate. The microstructure and phase composition of coatings were characterized, and the investigation on oxidation resistance and anti-oxidation mechanism was emphasized. The as-fabricated coatings consisting of SiO_2-rich mullite phase and Y_2Si_2O_7 phase show high density and favorable bonding to C/Si C composites. After oxidized at 1 400 ℃ and 1 500 ℃ for 30 min in static air, the coating-containing C/Si C composites possess 91.9% and 102.4% of the original flexural strength, respectively. The desirable thermal stability of coatings and the further densification of coatings due to viscous flow of rich SiO_2 and Y-Si-Al-O glass are responsible for the excellent oxidation resistance. In addition, the coating-containing composites retain 99.0% of the original flexural strength and the coatings exhibit no cracking and desquamation after 12 times of thermal shock from 1 400 ℃ to room temperature, which are ascribed to the combination of anti-oxidation mechanism and preferable physical and chemical compatibility among C/Si C composites, mullite and Y_2Si_2O_7. The carbothermal reaction at 1 600 ℃ between free carbon in C/Si C substrate and rich SiO_2 in mullite results in severe frothing and desquamation of coatings and obvious degradation in oxidation resistance. 展开更多
关键词 anti-oxidation coatings mullite yttrium silicate C/SiC composites
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Contrastive Study on Content and Anti-oxidation Activity of Total Saponins from Cultivated and Wild Paris Plants in Southwest China 被引量:3
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作者 Mengjie YU Haiyan XIANG +2 位作者 Shaoshan ZHANG Zhongjie HUANG Yuan LIU 《Medicinal Plant》 2017年第1期7-11,共5页
[Objectives]To study content of total saponins from cultivated and wild Paris herbs in Southwest China,evaluate its in vitro antioxidation activity,and explore the correlation between quality of Paris herbs and produc... [Objectives]To study content of total saponins from cultivated and wild Paris herbs in Southwest China,evaluate its in vitro antioxidation activity,and explore the correlation between quality of Paris herbs and production place,variety,cultivated and wild varieties.[Methods]Colorimetric method of perchloric acid reaction was used,and content of total saponins from Paris herbs was determined by ultraviolet spectrophotometer at 406 nm. [Results]The lowest content of total saponins from cultivated and wild Paris herbs in Southwest China was0. 55%,while the maximum was 12. 24%,with obvious difference. Total saponins from Paris herbs had stronger clearance ability on free radical DPPH and stronger reduction ability on Fe^(3+),and the results showed good dose-effect relationship with concentration. Among them,S6 had the highest clearance ability on DPPH,which reached 89. 66%. In the determination of reduction ability,the absorbance of S16 reached3. 643 and was the highest,with very good reducing property. Content and anti-oxidation capacity of total saponins from Paris herbs in Southwest China did not have obvious correlation with production place,altitude and cultivation but was related to variety. [Conclusions]The quality of Paris herbs in Southwest China was unstable,and their anti-oxidation abilities were also different,and cultivation could not guarantee high quality. It should normalize cultivation,and develop planting industry of Paris herbs,which could guarantee stable supply of Paris herbs and stability and controllability of quality. 展开更多
关键词 CULTIVATED and WILD PARIS herbs UV-VISIBLE spectrophotometry Total SAPONINS anti-oxidation
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Orthogonal Test Optimization of Extraction Technology of Total Fla-vonoids from Fruits and Leaves of Prunus mume Sieb. et Zucc. and Its in Vitro Anti-oxidation Activity 被引量:4
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作者 Xue ZHAI Qian JIN +2 位作者 Haiyan XIANG Fenglin WANG Yuan LIU 《Medicinal Plant》 2017年第2期25-31,36,共8页
[Objectives]To optimize the extraction technology of total flavonoids component,and investigate its in vitro anti-oxidation activity.[Methods]The single factor was inspected firstly. By orthogonal experiment,the best ... [Objectives]To optimize the extraction technology of total flavonoids component,and investigate its in vitro anti-oxidation activity.[Methods]The single factor was inspected firstly. By orthogonal experiment,the best extraction conditions of total flavonoids from fruits and leaves of P. mume Sieb. et Zucc. were determined,and reducing ability of the extracted total flavonoids and its DPPH and ABTS scavenging abilities were explored. [Results] The best extraction technology conditions: solid-liquid ratio of 1∶ 50,ethanol concentration of 50%,extraction time of 2. 5 h,extraction temperature of 85 ℃,two-time extraction. By detecting DPPH and ABTS scavenging abilities of total flavonoids,the anti-oxidation activity of the total flavonoids from fruits and leaves of P. mume Sieb. et Zucc. was analyzed and evaluated. [Conclusions]Fruits and leaves of P. mume Sieb. et Zucc. had a certain in vitro anti-oxidation activity,and heat reflux extraction method of its total flavonoids had high extraction rate and simple and convenient operation,which had some practical value. 展开更多
关键词 Prunus mume Sieb. ET Zucc. FRUITS and LEAVES anti-oxidation TOTAL flavonoids Orthogonal process
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Anti-oxidation mechanism of SiC-B_4C-C composites
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作者 刘其城 徐协文 +1 位作者 黄启忠 黄伯云 《中国有色金属学会会刊:英文版》 EI CSCD 2005年第6期1346-1350,共5页
Mixture of green petroleum coke, B4C and SiC together with short carbon fiber were employed as starting materials, the mixture was press-formed without any binder after grinding, dense and homogeneous binderless SiC-B... Mixture of green petroleum coke, B4C and SiC together with short carbon fiber were employed as starting materials, the mixture was press-formed without any binder after grinding, dense and homogeneous binderless SiC-B4C-C(carbon/ceramic) composites were then obtained after sintering. Composites thus prepared possess excellent anti-oxidation property, that is, mass loss less than 1% within the temperature range from 900 to 1100℃ for 10h. Anti-oxidation mechanism was also discussed from the viewpoint of thermodynamics, excellent anti-oxidation property of materials thus prepared can be discribed to 1) solid SiO2 formed from SiC, which restrains the filtering of oxygen and simultaneously, its volume expansion brought about by the reaction takes roles both walling up the (original) pores and making the material more compact; 2) liquid B2O3 from the reaction of B4C not only makes the combination with C, B4C and SiC tighter through forming solid solution, but also effect of reaction SiC(s)+2CO(g)=SiO2(s)+3C(s) is an expansive process, which improves the microstructure of the material. 展开更多
关键词 C-C复合材料 SIC B4C 石油焦 抗氧化机制
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Effects of Al, Ga, and Ag on the anti-oxidation and wetting reactions of Sn-gZn-X solders
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作者 王慧 薛松柏 陈文学 《China Welding》 EI CAS 2009年第2期57-61,共5页
The effects of Ca, Al, and Ag on the anti-oxidation of Sn-9Zn-X solders and the interface reactions between the solders and Cu substrate were investigated by Auger electron spectroscopy ( AES ) and scanning electron... The effects of Ca, Al, and Ag on the anti-oxidation of Sn-9Zn-X solders and the interface reactions between the solders and Cu substrate were investigated by Auger electron spectroscopy ( AES ) and scanning electron microscope (SEM) analysis, respectively. The mechanism of improving the wettability of Sn-9Zn lead-free solder by adding Ca, Al, and Ag was also revealed. The AES analysis indicated that Al and Ga might enrich on the molten solder surface which resulted in improving the anti-oxidation of Sn-9Zn-O. O05Al and Sn-9Zn-O. 3Ga alloys. The addition of Ga reduced the apparent activation energy and promoted the interface reaction. With the addition of 0. 3 wt. % Ag, some scallop-like intermetallic compounds (IMCs) formed at the interface, according to the energy dispersive spectroscopy (EDS) analysis, these scallop-like IMCs might be the mixture of Ag-Zn and Cu-Sn compounds. 展开更多
关键词 lead-free solder SN-ZN anti-oxidation interface reaction
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Comparison of Lipid Peroxidation and Anti-Oxidant Ac-tivities in Pre-Eclamptic &Normal Pregnancies in Nigerian Population
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作者 Adetunji O. Adeniji Dolapo P. Oparinde 《International Journal of Clinical Medicine》 2013年第5期239-243,共5页
Purpose: To compare the serum malondialdehyde (MDA) and total antioxidant status in women with preeclampsia and normal pregnancy in our environment. Materials & Methods: This was a 3-year, cross-sectional, case co... Purpose: To compare the serum malondialdehyde (MDA) and total antioxidant status in women with preeclampsia and normal pregnancy in our environment. Materials & Methods: This was a 3-year, cross-sectional, case control study of 100 preeclamptic and 200 normotensive pregnant women at Ladoke Akintola University of Technology (LAUTECH) Teaching Hospital, Osogbo, Nigeria. The study protocol was reviewed and approved by our Institutional Ethical Review Committee and all participants gave their consent. The fasting serum of recruited patients were analysed for Malondialdehyde (MDA) with rapid, sensitive and specific Thiobarbituric Acid (TBA) assay, while the Total Antioxidant status (TAS) was determined using the capacity of the biological fluids to inhibit the production of thiobarbituric acid reactive substances (TBARS) from sodium benzoate under the influence of the free oxygen radicals derived from Fenton’s reaction. Results: The mean serum MDA was significantly higher in the preeclamptic group (2.96 nmol/ mL) than the value recorded (1.23 nmol/mL) in the control group (P = 0.0001). Conversely, significantly lower mean TAS (0.46 nmol/mL vs 0.62 nmol/mL) was noticed in the preeclamptic group (P = 0.0001). Conclusion: The study showed significant increase in lipid peroxidation and failure of compensatory antioxidant functions in preeclamptic pregnant Nigerian women. 展开更多
关键词 Lipid PERoxidation anti-oxidANT Status PREECLAMPSIA MALONDIALDEHYDE
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The profiles of lipid peroxidation and anti-oxidant activities in gestational diabetes mellitus &normal pregnancies in Nigerian population
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作者 Adetunji O. Adeniji Dolapo P. Oparinde 《Open Journal of Obstetrics and Gynecology》 2013年第6期472-476,共5页
Purpose: To compare the Lipid peroxidation and Total antioxidant status in women with gestational diabetes mellitus and normal pregnancy in our environment. Materials & Methods: This was a 2-year, cross sectional,... Purpose: To compare the Lipid peroxidation and Total antioxidant status in women with gestational diabetes mellitus and normal pregnancy in our environment. Materials & Methods: This was a 2-year, cross sectional, case control study of 25 gestational diabetes mellitus (GDM) and 75 matched normal pregnant women at Ladoke Akintola University of Technology (LAUTECH) Teaching Hospital, Osogbo, Nigeria. The study protocol was reviewed and approved by our Institutional Ethical Review Committee and all participants gave their consents. The fasting serum of recruited patients were analysed for lipid peroxidetion product malondialdehyde(MDA), based on MDA reaction with thiobarbituric acid (TBA), with rapid, sensitive and specific Thiobarbituric Acid (TBA) assay, while the Total Anti-oxidant status (TAS) was determined using the capacity of the biological fluids to inhibit the production of thiobarbituric acid reactive substances (TBARS) from sodium benzoate under the influence of the free oxygen radicals derived from Fenton’s reaction. Results: The mean serum MDA was significantly higher in the GDM group (3.64 nmol/mL) than the value recorded (1.33 nmol/ mL) in the control group (P vs. 0.66 nmol/mL) was noticed in the GDM group (P < 0.0001). Conclusion: The study showed significant increase in lipid peroxidation and failure of compensatory antioxidant functions in GDM Nigerian women. 展开更多
关键词 Lipid PERoxidation anti-oxidANT Status GESTATIONAL Diabetes Mellitus MALONDIALDEHYDE
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Preparation and Anti-oxidative Effects of Corn Peptides 被引量:5
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作者 XU Li ZHANG Xue-zhong +2 位作者 GUO Yi REN Qiao WU Xiao-xia 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2002年第3期299-302,共4页
Corn peptides(CP) were prepared from zein via proteolysis by means of a type of alkaline protease, Alcalase, at 50 ℃ and pH 8.0. The anti oxidative activity of the hydrolysate was examined. It was found that the... Corn peptides(CP) were prepared from zein via proteolysis by means of a type of alkaline protease, Alcalase, at 50 ℃ and pH 8.0. The anti oxidative activity of the hydrolysate was examined. It was found that the anti oxidative activity reached the maximum at the fourth hour of the hydrolysis and then decreased. The effect of the enzyme dosage on the solubility of corn protein, the dependence of hydrolysis time on the degree of the hydrolysis(DH) and molecular weight distribution were examined respectively. 30% DH was controlled on the basis of anti oxidative activity. The hydrolysate was fractionated on a Sephadex G 15 column. The anti oxidative activities were examined for all the fractions. The main fraction for anti oxidative activity was collected and characterized by the methods of amino acid analysis, the measurement of average chain length and etc .. The main M W distribution of the main fraction was 300-600 Daltons. The anti oxidative properties of the small peptides in vitro were studied. It was found that they could inhibit the auto oxidation of pyrogallol and the oxidation of hemoglobin. The hemolysis degree of erythrocyte caused by hydroxyl free radicals was decreased greatly, indicating a protective effect of the anti oxidative peptides on the cell membrane damage of erythrocyte. 展开更多
关键词 Corn Peptides PREPARATION anti oxidative effect
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Methane Oxidation to Synthesis Gas Using Lattice Oxygen of La_(1-x)Sr_xMO_(3-λ)(M =Fe,Mn) Perovskite Oxides Instead of Molecular Oxygen 被引量:10
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作者 LiRanjia YuChangchun ZhuGuangrong ShenShikong 《Petroleum Science》 SCIE CAS CSCD 2005年第1期19-23,共5页
In this paper, the partial oxidation of methane to synthesis gas using lattice oxygen of La1- SrxMO3-λ (M=Fe, x ... In this paper, the partial oxidation of methane to synthesis gas using lattice oxygen of La1- SrxMO3-λ (M=Fe, x Mn) perovskite oxides instead of molecular oxygen was investigated. The redox circulation between 11% O2/Ar flow and 11% CH4/He flow at 900℃ shows that methane can be oxidized to CO and H2 with a selectivity of over 90.7% using the lattice oxygen of La1- SrxFeO3-λ (x≤0.2) perovskite oxides in an appropriate reaction condition, while the lost lattice x oxygen can be supplemented by air re-oxidation. It is viable for the lattice oxygen of La1- SrxFeO3-λ (x≤0.2) perovskite x oxides instead of molecular oxygen to react with methane to synthesis gas in the redox mode. 展开更多
关键词 Partial oxidation METHANE synthesis gas lattice oxygen La1- xSrxFeO3-λperovskite oxides
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