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Effect of acute alcoholism on hepatic enzymes and oxidation/antioxidation in rats 被引量:3
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作者 You-Ming Li, Shao-Hua Chen, Chao-Hui Yu, Yu Zhang and Gen-Yun Xu Hangzhou, China Department of Digestive Medicine, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003 . Chi- na 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2004年第2期241-244,共4页
BACKGROUND: Around the world more and more people suffer from acute alcoholism. The purpose of this study was to determine hepatic enzymes and oxidation/antioxidation in rats with acute alcoholism. METHODS: Rats were ... BACKGROUND: Around the world more and more people suffer from acute alcoholism. The purpose of this study was to determine hepatic enzymes and oxidation/antioxidation in rats with acute alcoholism. METHODS: Rats were randomly divided into three groups; control, low-dose alcohol, and high-dose alcohol. Each al- cohol group ( n = 12) was intravenously infused with etha- nol at a dose of 0.3 or 0.7 g/kg body weight respectively. The control group (n =11) was intravenously infused with normal saline at a dose of 0.5 g/kg body weight. Blood was collected for detection of hepatic enzymes and index of oxidation/antioxidation. RESULTS: The ratio of AST to ALT was 2.44±0.46, 2.57± 0.60 and 3.03 ±0.46 in the three groups, and the difference was significant between the control and high-dose alcohol groups (P^0.05). No significant changes were observed in the levels of serum alanine aminotransferase (ALT), aspar- tate aminotransferase (AST), total protein (Tp), albumin (Alb), alkaline phosphatase (ALP), cholinesterase (ChE), total bilirubin (TB), C-reactive protein (CRP) and amy- lase. The levels of serum nitric oxide (NO) in the 3 groups were 39.2 ±73.25 mol/L, 42.30 ±4.60 mol/L and 47.86± 4.66 mol/L, and significant difference was seen between the control group and the high-dose alcohol group (P < 0.01). No significant difference was found in the levels of serum superoxide dismutase (SOD), glutathione (GSH), malondiethylaldehyde (MDA), and CRP in the 3 groups. CONCLUSION: The ratio of AST to ALT appears to be a useful index for acute alcohol intoxication. NO is involved in the mechanism of acute alcohol intoxication. 展开更多
关键词 ALCOHOLISM INFUSION nitric oxide oxidation/antioxidation animal model hepatic enzyme
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Marine fungal metabolite butyrolactone Ⅰ improves Aβ_(1-42)-induced cognitive impairment in mice via gut-brain axial microbiota remodeling,anti-inflammation,and antioxidation
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作者 Fuyan YANG Longjian ZHOU +5 位作者 Jiahang DENG Yuan WANG Zhiyou YANG Yongping ZHANG Yayue LIU Yi ZHANG 《Journal of Oceanology and Limnology》 2026年第1期386-405,共20页
Alzheimer’s disease(AD)is a complex neurodegenerative disorder associated with changes in inflammation,oxidative stress,and gut microbiota composition.Butyrolactone Ⅰ(BTL-Ⅰ),a fungal metabolite,has shown anti-infla... Alzheimer’s disease(AD)is a complex neurodegenerative disorder associated with changes in inflammation,oxidative stress,and gut microbiota composition.Butyrolactone Ⅰ(BTL-Ⅰ),a fungal metabolite,has shown anti-inflammatory,microbiota regulating,and memory-improving potentials in previous in vitro and AlCl3-induced zebrafish studies.However,its effects of memory-improving and gutbrain axis regulating on Aβ-induced mammalian AD models have not been explored.In this study,intragastric administrated BTL-Ⅰ ameliorated cognitive deficits related to recognition and spatial memory impaired by Aβ_(1-42)intracerebroventricular injection in mice.BTL-Ⅰ maintained gut microbiota balance by increasing the abundance of Blautia,Muribaculaceae,Bacteroides,Akkermansia,etc.,and decreasing CAG-352,Clostridia UCG-014,different Lachnospiraceae groups,etc.,and Firmicutes/Bacteroidota ratio and elevated the levels of short-chain fatty acids.Additionally,it alleviated intestinal oxidative stress,inflammatory responses,and pathological damage.Furthermore,BTL-I reversed Aβ_(1-42)-induced activation of microglia and astrocytes in the hippocampus and inhibited the elevated oxidative stress and proinflammatory cytokines in both plasma and brain.The correlation analysis between the regulated taxa and biomarkers supports the role of gut microbiota in adjusting inflammation,oxidative stress,and memory.In conclusion,BTL-I may serve as a valuable drug lead for treating Alzheimer’s disease by systematically inhibiting microbiota imbalance,inflammation,and oxidative stress along the gut-brain axis. 展开更多
关键词 Alzheimer’s disease butyrolactoneⅠ cognitive deficit microbiota composition oxidative stress NEUROINFLAMMATION
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Hypidone hydrochloride(YL-0919)ameliorates functional deficits after traumatic brain injury in mice by activating the sigma-1 receptor for antioxidation 被引量:2
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作者 Yafan Bai Hui Ma +5 位作者 Yue Zhang Jinfeng Li Xiaojuan Hou Yixin Yang Guyan Wang Yunfeng Li 《Neural Regeneration Research》 SCIE CAS 2025年第8期2325-2336,共12页
Traumatic brain injury involves complex pathophysiological mechanisms,among which oxidative stress significantly contributes to the occurrence of secondary injury.In this study,we evaluated hypidone hydrochloride(YL-0... Traumatic brain injury involves complex pathophysiological mechanisms,among which oxidative stress significantly contributes to the occurrence of secondary injury.In this study,we evaluated hypidone hydrochloride(YL-0919),a self-developed antidepressant with selective sigma-1 receptor agonist properties,and its associated mechanisms and targets in traumatic brain injury.Behavioral experiments to assess functional deficits were followed by assessment of neuronal damage through histological analyses and examination of blood-brain barrier permeability and brain edema.Next,we investigated the antioxidative effects of YL-0919 by assessing the levels of traditional markers of oxidative stress in vivo in mice and in vitro in HT22 cells.Finally,the targeted action of YL-0919 was verified by employing a sigma-1 receptor antagonist(BD-1047).Our findings demonstrated that YL-0919 markedly improved deficits in motor function and spatial cognition on day 3 post traumatic brain injury,while also decreasing neuronal mortality and reversing blood-brain barrier disruption and brain edema.Furthermore,YL-0919 effectively combated oxidative stress both in vivo and in vitro.The protective effects of YL-0919 were partially inhibited by BD-1047.These results indicated that YL-0919 relieved impairments in motor and spatial cognition by restraining oxidative stress,a neuroprotective effect that was partially reversed by the sigma-1 receptor antagonist BD-1047.YL-0919 may have potential as a new treatment for traumatic brain injury. 展开更多
关键词 antidepressant drug blood-brain barrier cognitive function hypidone hydrochloride(YL-0919) neurological function nuclear factor-erythroid 2 related factor 2 oxidative stress sigma-1 receptor superoxide dismutase traumatic brain injury
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Oxidation behavior of Ti55 alloy and TiBw/Ti55 composites and antioxidation mechanism of TiBw in composites at 960–1000℃
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作者 Guangyu Liu Lian Li Miaoquan Li 《Journal of Materials Science & Technology》 2025年第10期55-68,共14页
The oxidation behavior of Ti55 alloy and TiBw/Ti55 composites at temperatures ranging from 960 to 1000℃ was investigated by characterizing the surface and cross-section microstructure of specimens.Results showed that... The oxidation behavior of Ti55 alloy and TiBw/Ti55 composites at temperatures ranging from 960 to 1000℃ was investigated by characterizing the surface and cross-section microstructure of specimens.Results showed that TiBw reinforcement accelerated the occurrence of Ti_(6O)/Ti_(3O) by dissolving oxygen in titanium in the starting oxidation stage,and the Ti_(6O)/Ti_(3O) transformed into TiO_(2) with the progression of oxidation.Meanwhile,TiBw reinforcement promoted the formation of(101)crystal planes to be beneficial to the growth of TiO_(2) twins.The cross-sectional characterization showed that the oxide layer of Ti55 alloy and TiBw/Ti55 composites from outside to inside was TiO_(2)+Al_(2)O_(3),TiO_(2),Ti-Sn compounds,Ti_(6O)/Ti_(3O) in sequence,which was confirmed by calculating the standard Gibbs free energy of the oxide nucleation.The TiBw reinforcement accelerated the occurrence of suboxides Ti_(6O)/Ti_(3O) by dissolving oxygen in titanium,and promoted the formation of(101)crystal planes which were beneficial to the growth of TiO_(2) twins.The optimal addition of TiBw induced the TiO_(2) twins,promoted the random orientation of oxides and refined the oxide size of the TiBw/Ti55 composites with 3.5%volume fractions of TiBw,resulting in the best resistance against oxidation. 展开更多
关键词 Titanium alloy Titanium matrix composite TiBw oxidation behavior oxidE TWIN
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Phytochemicals, Antioxidation, and Heat Stability of Aqueous Extracts from Cherry (Prunus serrulata) Petals
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作者 Sy-Yu Shiau Shuting Ni +2 位作者 Yanli Yu Songling Cai Wenbo Huang 《Phyton-International Journal of Experimental Botany》 2025年第10期3047-3060,共14页
Consumers are increasingly demanding natural colorants that are safe and offer health benefits.In addition to their ornamental characteristics,Kanzan cherry(KC)blossoms present a promising source of red-hued natural c... Consumers are increasingly demanding natural colorants that are safe and offer health benefits.In addition to their ornamental characteristics,Kanzan cherry(KC)blossoms present a promising source of red-hued natural colorants and functional bioactive substances.This research utilized distilled water to extract KC petals(KCP)and their ground powders(KCPP)under varying temperatures(30℃–90℃)and times(30–180 min).The total monomeric anthocyanins(TMAC)and total phenolics(TPC)in the extracts were evaluated via the pH differential and Folin–Ciocalteu methods.Antioxidant capacities were assessed by DPPH free radical scavenging ability and reducing power.Results indicated that the optimal extraction of TMAC and TPC from KCP occurred at 90℃ for 30 min,and the resulting extracts exhibited the highest antioxidant activities among all tested temperatures and durations.Compared to different particle sizes,the finest KCPP generally produced extracts with the highest TMAC,TPC,and antioxidant activity,due to enhanced mass and heat transfer.When compared with the acidified alcohol method,hot water extraction resulted in 68.23%and 71.41%TMAC yields for petals and powders,respectively,while TPC levels were similar or higher.TMAC or TPC showed a significantly positive correlation(p<0.01)with the antioxidant activities.These findings demonstrate that hot water extraction is a viable and environmentally friendly alternative for phytochemical recovery from KC.Additionally,elevated extraction temperature and pH accelerated anthocyanin degradation and shortened its half-life,while higher pH also lowered the activation energy,enthalpy,entropy,and Gibbs free energy.Thus,red–orange KC extracts with rich bioactivity may serve as promising ingredients for functional foods having acidic pH levels. 展开更多
关键词 Cherry blossom extraction ANTHOCYANIN phenolics antioxidant kinetics thermodynamics
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Corrosion Behavior,Antioxidation Property,Antibacterial Ability,and Osteogenic Activity of Zn/Chitosan-Catechol Coating Prepared on NiTi Alloy
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作者 Shuaiwu Peng Zejun Chen +5 位作者 Runhua Yao Sen Pei Ruiqiang Hang Yonghua Sun Xiaohong Yao Ying Lu 《Acta Metallurgica Sinica(English Letters)》 2025年第11期1909-1925,共17页
NiTi alloy has been widely used as orthopedic implant materials due to its unique shape memory properties and superelasticity.However,implantation failure often occurs because of the poor antibacterial ability,antioxi... NiTi alloy has been widely used as orthopedic implant materials due to its unique shape memory properties and superelasticity.However,implantation failure often occurs because of the poor antibacterial ability,antioxidation property and corrosion resistance of the NiTi alloy.In order to overcome the above problems,we constructed Zn/polydopamine(PDA)/Chitosan-Catechol(CS-C)composite coating on the surface of NiTi alloy in this paper.The surface morphology and wettability of the coating were characterized by scanning electron microscopy(SEM)and optical contact angle measuring instrument,respectively.The results showed that the Zn/CS-C coating was successfully prepared,and exhibited good hydrophilic property,especially the sample Zn/PDA/CS-C-24 h.In addition,the corrosion resistance,antioxidation property and biological properties of the coating were systematically analyzed.The results indicated that the Zn/PDA/CS-C composite coating exhibited good corrosion resistance and antibacterial property,antioxidant property and osteogenic activity,especially sample Zn/PDA/CS-C-24 h.The sample Zn/PDA/CS-C-24 h could effectively protect osteoblasts from reactive oxygen species(ROS)damage and promote cell proliferation and osteoblast differentiation.This study provides a feasible and effective strategy for the surface modification of orthopedic implant. 展开更多
关键词 NiTi alloy Chitosan-catechol Corrosion behavior antioxidation property Antibacterial ability Osteogenic activity
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Study on Antioxidation Effect of Polyphenols from Pomegranate Peel in Vivo 被引量:2
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作者 傅力 徐佳 +2 位作者 包晓玮 赵晓梅 叶凯 《Agricultural Science & Technology》 CAS 2016年第1期164-167,共4页
[Objective] The aim was to study the antioxidant effect of polyphenols from pomegranate peel in vivo. [Method] The Kunming rats were randomly divided into a control group, a low-dose group, a middle-dose group and a h... [Objective] The aim was to study the antioxidant effect of polyphenols from pomegranate peel in vivo. [Method] The Kunming rats were randomly divided into a control group, a low-dose group, a middle-dose group and a high-dose group,n=10; the protein content, the activities of the superoxide dismutase(SOD) and the glutathione peroxidase(GSH-PX), the content of the maleic dialdehyde(MDA) in serum and liver tissue of the rats from different groups were determined. [Result]The polyphenols of pomegranate peel could increase protein content, activities of superoxide dismutase(SOD) and glutathione peroxidase(GSH-PX) in serum and liver tissue, and decrease the maleic dialdehyde(MDA) content simultaneously. [Conclusion] Polyphenols of pomegranate peel have strong antioxidant activity in vivo. 展开更多
关键词 Pomegranate peel POLYPHENOLS antioxidation In vivo
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Comparisons between Phenolic Compounds and Antioxidation of Momordica charantia L. in Different Varieties 被引量:1
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作者 黄龙 邓媛元 +4 位作者 张名位 张雁 魏振承 张瑞芬 唐小俊 《Agricultural Science & Technology》 CAS 2012年第6期1263-1269,共7页
[Objective] The aim was to compare contents of free and bound polyphenol and antioxidation of balsam pear in different varieties. [Method] Fourteen varieties of balsam pear were chosen to analyze total contents of fre... [Objective] The aim was to compare contents of free and bound polyphenol and antioxidation of balsam pear in different varieties. [Method] Fourteen varieties of balsam pear were chosen to analyze total contents of free or bound phenol and components of free phenol. FRAP (Freeic reducing/antioxidant power), DPPH (1,1diphenyl-2-picrylhydrazy), and ABTS +· (2, 2’-azinobis-3-ethylbenzothiazoline-6-sulphonic acid diammonium salt) were used to measure antioxidation and analyze relationship between polyphenol content and antioxidation. [Result] Among the fourteen varieties of balsam pear, free, bound and total phenols were 157.58 -382.92, 6.46 -54 and 175.27 -413.79 mg GAE/100 g DW; coefficients of variance were 23.50% , 61.04% and 21.58%, respectively; free phenol accounted for 91.34% of total phenol and bound phenol accounted for 8.66% ; contents of total flavone for the fourteen varieties were from 8.97 to 18.22 mg CE/100 g DW and the coefficient was at 22.80%; vanillic aldehyde acid, epicatechin and rutin differed in contents among different varieties, which changed in 1.83-9.29, 35.17-114.52 and 0.91-4.53 mg/100 g DW and the coefficients were 43.85%, 26.97% and 33.09%; FRAP antioxidation was at 272.16 -713.32 mg TE/100 g DW and coefficient at 27.67% ; IC 50 of DPPH and ABTS +· clearance were 11.43-34.14 and 21.57-119.71 mg GAE/100 g DW and coefficients were at 35.10% and 63.75% , accordingly; content of total phenol was of extremely positive correlation with FRAP (P0.01) and of extremely negative correlation with IC 50 of DPPH and ABTS + · clearance (P0.01). [Conclusion] Contents of phenolic compounds and antioxidation are of significant genotype differences; and phenolic substance and antioxidation are mainly in free form and phenolic substance is the major basis for antioxidation. 展开更多
关键词 Momordica charantia L. Phenolic compounds antioxidation
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Effect of Substrate Micro-arc Oxidation Pretreatment on Microstructure and High-Temperature Oxidation Resistance of Si-Cr-Ti-Zr Coating on Ta12W Alloy
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作者 Yang Fan Chang Jianxiu +2 位作者 Wang Xin Li Hongzhan Yan Peng 《稀有金属材料与工程》 北大核心 2026年第1期92-104,共13页
To mitigate the impact of interdiffusion reactions between the silicide slurry and Ta12W alloy substrate during vacuum sintering process on the oxidation resistance of the silicide coating,a micro-arc oxidation pretre... To mitigate the impact of interdiffusion reactions between the silicide slurry and Ta12W alloy substrate during vacuum sintering process on the oxidation resistance of the silicide coating,a micro-arc oxidation pretreatment was employed to construct a Ta_(2)O_(5)ceramic layer on the Ta12W alloy surface.Subsequently,a slurry spraying-vacuum sintering method was used to prepare a Si-Cr-Ti-Zr coating on the pretreated substrate.Comparative studies were conducted on the microstructure,phase composition,and isothermal oxidation resistance(at 1600℃)of the as-prepared coatings with and without the micro-arc oxidation ceramic layer.The results show that the Ta_(2)O_(5)layer prepared at 400 V is more continuous and has smaller pores than that prepared at 350 V.After microarc oxidation pretreatment,the Si-Cr-Ti-Zr coating on Ta12W alloy consists of three distinct layers:an upper layer dominated by Ti_(5)Si_(3),Ta_(5)Si_(3),and ZrSi;a middle layer dominated by TaSi_(2);a coating/substrate interfacial reaction layer dominated by Ta_(5)Si_(3).Both the Si-Cr-Ti-Zr coatings with and without the Ta_(2)O_(5)ceramic layer do not fail after isothermal oxidation at 1600℃for 5 h.Notably,the addition of the Ta2O5 ceramic layer reduces the high-temperature oxidation rate of the coating. 展开更多
关键词 tantalum-tungsten alloy silicide coating micro-arc oxidation reaction formation mechanism high-temperature oxidation
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Facile Fabrication of Ceramic-resin Coatings on C/CA Composites for Oxidation Protection at Medium Temperatures
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作者 TIAN Hongwang LUO Longfei +4 位作者 HU Chenglong YAN Meng PANG Shengyang LI Jian TANG Sufang 《无机材料学报》 北大核心 2026年第3期401-408,I0008-I0011,共12页
Carbon fiber-reinforced carbon aerogel(C/CA)composites are one of the most promising candidates for applications requiring both thermal insulation and load bearing capabilities.The preparation of anti-oxidation coatin... Carbon fiber-reinforced carbon aerogel(C/CA)composites are one of the most promising candidates for applications requiring both thermal insulation and load bearing capabilities.The preparation of anti-oxidation coatings on C/CA to address its susceptibility to oxidation is a feasible approach to promote its application in oxidative environments.However,the currently reported coatings on C/CA mainly focus on improving the ablation performance and coating preparation process typically necessitating high-temperature heat treatment.This procedure can increase its thermal conductivity and reduce its thermal insulation ability.In this study,a series of ceramic-resin coatings were fabricated on C/CA through a simple slurry brushing-drying approach at room temperature.The effects of phenolic resin content on the coating structure,residual stress,thermal shock,and oxidation behaviors were investigated.Due to the adhesive properties and curing-induced shrinkage,the PR-7.5 coating(containing 7.5%(in mass)phenolic resin in the slurry)exhibits bonding strength close to fracture strength of the substrate and residual compressive stress of 0.853 GPa,which is beneficial for resisting thermal shock cracking.However,excessive resin content(PR-10.0 containing 10.0%(in mass)phenolic resin in the slurry)induces tensile stress due to uneven curing shrinkage,thereby leading to thermal shock cracking.Meanwhile,oxidation tests reveal significantly reduced weight losses for PR-7.5(17.46%at 800℃/100 min,8.15%at 1000℃/120 min,3.15%at 1200℃/120 min)versus uncoated C/CA’s 44.60%loss at 800℃/20 min.This work provides a brand-new and simple approach to improving the anti-oxidation performance of C/CA and expands its application in mild oxidative environments. 展开更多
关键词 C/CA composite coating oxidation residual stress interfacial bonding
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Recent advances in high-temperature oxidation behavior and underlying mechanisms of Mg-RE alloys:A comprehensive review
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作者 Yu Ma Yu Cao +4 位作者 Yulian Kuang Yajun Wang Yuhao Gong Bin Jiang Jonghyun Kim 《International Journal of Minerals,Metallurgy and Materials》 2026年第2期446-466,共21页
The limited high-temperature oxidation resistance of Mg alloys is a key factor restricting their development and application.The addition of some rare earth elements(REs),owing to their unique physical and chemical pr... The limited high-temperature oxidation resistance of Mg alloys is a key factor restricting their development and application.The addition of some rare earth elements(REs),owing to their unique physical and chemical properties,can significantly enhance the oxidation resistance of Mg alloys.Based on our previous study,we conclude that REs such as Gd,Y,and Ce enhance the oxidation resistance of Mg-RE alloys.This article comprehensively reviews recent research progress on high-temperature oxidation behavior and the potential mechanism in Mg-RE alloys.Based on the thermodynamic and kinetic analyses,the evolution of the complex oxide system formed during the high-temperature oxidation of Mg-RE alloys is first summarized.The diffusion behavior and concentration control mechanisms of REs during the oxidation process and how these mechanisms affect the sustained growth of the oxide film and antioxidant properties were elucidated.Moreover,the different structures of the oxide films were classified,and their properties were discussed.Finally,this paper introduces the applications of commonly used REs in Mg alloys and frontier research on their oxidation mechanisms.Based on the above review,we propose that future research perspectives can be explored in terms of expanding the experimental temperature range for oxidation tests,optimizing the chemical composition by adding trace REs to study their synergistic mechanism,revealing the underlying oxidation mechanism through advanced in situ microscopic characterization methods,and investigating the mechanical properties of oxide films using diverse approaches. 展开更多
关键词 magnesium-rare earth element alloy high-temperature oxidation THERMODYNAMICS oxidation resistance oxide films
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Oxidation behaviors of 430 ferritic stainless steel under coupling of electrical current and high temperature:quantitative evaluation for SOFC interconnector
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作者 Hao Xie Yu-Nong Lei +6 位作者 Guo-Zun Tang Lin Hu Xing-Yue Liu Ao Huang Hua-Zhi Gu Jin-Yu Wang Lu Gan 《Journal of Iron and Steel Research International》 2026年第1期15-23,共9页
To elucidate the accelerated degradation mechanisms of metallic interconnects in operational solid oxide fuel cells,the oxidation behavior of FSS430 ferritic stainless steel under the coupling of simultaneous electric... To elucidate the accelerated degradation mechanisms of metallic interconnects in operational solid oxide fuel cells,the oxidation behavior of FSS430 ferritic stainless steel under the coupling of simultaneous electrical current and high-temperature exposure is investigated.Isothermal thermogravimetric analysis was employed to quantify oxidation kinetics,complemented by microstructural characterization using X-ray diffraction,scanning electron microscopy with energy-dispersive spectroscopy and transmission electron microscopy.Experimental results demonstrate that the applied current dramatically enhances oxidation rates,increasing specific mass gain from 0.25 mg/cm^(2)(0 A/cm^(2))to 5.20 mg/cm^(2)(0.2 A/cm^(2))and oxide scale thickness from 1.87 to 15.62μm after 200 h.This acceleration originates from current-induced electromigration forces that promote cationic transport through the oxide layer.The quantitative relationships between current density and oxidation parameters are established,enabling predictive modeling of interconnector degradation in solid oxide fuel cell(SOFC)systems. 展开更多
关键词 Stainless steel Electrical current High-temperature oxidation oxidation protection Solid oxide fuel cell
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Research Status and Prospects of Platinum Group Metal Coatings with High-Temperature Oxidation Resistance
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作者 Ding Chenxi Liu Zhongyu +3 位作者 Fang Zhen Wang Haoxu Lv Biao Hu Zhenfeng 《稀有金属材料与工程》 北大核心 2026年第2期333-344,共12页
Platinum group metals have high melting points,strong corrosion resistance,stable chemical properties,and low oxygen permeability in high-temperature oxygen-containing environments.As thermal protective coating materi... Platinum group metals have high melting points,strong corrosion resistance,stable chemical properties,and low oxygen permeability in high-temperature oxygen-containing environments.As thermal protective coating materials,they have gained essential applications in the aerospace field and have excellent prospects for application in frontier military fields,such as protecting hot-end components of hypersonic aircraft.This research reviewed the latest research progress of platinum group metal coatings with hightemperature oxidation resistance,including coating preparation techniques,oxidation failure,and alloying modification.The leading preparation techniques of current platinum group metal coatings were discussed,as well as the advantages and disadvantages of various existing preparation techniques.Besides,the intrinsic properties,failure forms,and failure mechanisms of coatings of single platinum group metal in high-temperature oxygen-containing environments were analyzed.On this basis,the necessity,main methods,and main achievements of alloying modification of platinum group metals were summarized.Finally,the future development of platinum group coatings with high-temperature oxidation resistance was discussed and prospected. 展开更多
关键词 platinum group metal coatings preparation technique high temperature oxidation resistance alloying modification
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Research on the oxidation mechanism of C_(2)H_(4)in automotive exhaust over MgO-supported Ag-Cu bimetallic synergistic catalysts
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作者 ZHANG Wei ZHAO Genrui +2 位作者 LI Zehong CHEN Guisheng CHEN Zhaohui 《燃料化学学报(中英文)》 北大核心 2026年第4期120-127,共8页
Ethylene(C_(2)H_(4))in vehicle exhaust is a highly reactive volatile organic compound(VOC).Its photooxidative reaction with NOx contributes to the formation of O3 and secondary organic aerosols(SOA),the latter being a... Ethylene(C_(2)H_(4))in vehicle exhaust is a highly reactive volatile organic compound(VOC).Its photooxidative reaction with NOx contributes to the formation of O3 and secondary organic aerosols(SOA),the latter being a key precursor of PM_(2.5).In this study,a novel MgO-supported Ag-Cu bimetallic catalyst was designed and investigated using density functional theory(DFT).The effects of Ag and Cu loading on the geometric structure,stability,and reactant adsorption characteristics of the catalyst were analyzed,and the catalytic oxidation pathways of C_(2)H_(4)over AgCu-MgO was elucidated.The results indicate that loading Ag significantly enhances the adsorption of C_(2)H_(4).The incorporation of Cu into Ag-MgO to form a AgCu-MgO bimetallic catalyst(dual atom catalyst,DACS)further improves the oxidative activity toward C_(2)H_(4).Based on the binding energies of the Ag and Cu bimetallic sites and the adsorption energies of C_(2)H_(4)and O_(2),three representative configurations were selected for detailed reaction pathway analysis.Among them,Configuration 6 of AgCu-MgO exhibited the highest catalytic oxidation performance.This study provides new atomic-scale insights for the rational design of efficient catalysts targeting olefinic pollutants in automotive emissions and offers valuable guidance for advancing exhaust after-treatment technologies. 展开更多
关键词 MGO AG-CU C_(2)H_(4) catalytic oxidation automotive exhaust
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Rational Design of a Perovskite-Type Catalyst for Toluene Oxidation Via Simultaneous Phosphorus Doping and Post-Synthesis Acidic Etching
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作者 Li Yang Kehan Yin +4 位作者 Chuang Shi Guidong Mu Shi Liu Yanzhi Li Zongping Shao 《Energy & Environmental Materials》 2026年第1期311-320,共10页
Perovskite oxides are highly promising catalysts for the combustion removal of volatile organic compounds(VOCs)due to their excellent stability,structural flexibility,and compositional versatility.This study presents ... Perovskite oxides are highly promising catalysts for the combustion removal of volatile organic compounds(VOCs)due to their excellent stability,structural flexibility,and compositional versatility.This study presents a novel perovskite oxide that exhibits enhanced catalytic activity and superior durability for toluene combustion at reduced temperatures.This improvement is achieved by phosphorus doping at the B-site of LaCoO_(3-δ)(LC)perovskite oxide,followed by post-synthesis acid etching for a proper time.The resulting catalyst demonstrates increased specific surface area,higher total pore volume,and enhanced oxygen vacancy concentration both in the bulk and on the surface.Additionally,the activity of surface lattice oxygen species is significantly improved,leading to enhanced catalytic performance in toluene combustion.Notably,the optimized catalyst shows an exceptionally low activation energy(E_(a))of 49.3 kJ mol^(-1),with a T90 reduction of over 214℃compared to the phosphorus doped LC and 190℃compared to pristine LC.Phosphorus doping plays a main role in significantly improving the long-term durability,particularly in the presence of CO_(2)and H_(2)O,while acid etching boosts the catalytic activity.This work introduces a rational and innovative strategy for optimizing VOC oxidation by improving the structure and surface chemical states of perovskite catalysts. 展开更多
关键词 acidic etching oxygen species perovskite oxides phosphorus doping toluene oxidation
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Influence of interfacial segregation of Sn microalloying on internal oxidation of Fe-Mn-Si based alloys
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作者 Wen-Tao Zhang Yi-Ming Liu +4 位作者 Qin Luo Wei-Chen Mao Ju-Feng Hong Xin-Yan Jin Guang-Xin Wu 《Journal of Iron and Steel Research International》 2026年第3期31-44,共14页
Severe internal oxidation formed in advanced high-strength steels(AHSSs)during the hot-rolled coiling process compromises subsequent cold rolling and galvanizing processes.Herein,we report how Sn microalloying governs... Severe internal oxidation formed in advanced high-strength steels(AHSSs)during the hot-rolled coiling process compromises subsequent cold rolling and galvanizing processes.Herein,we report how Sn microalloying governs internal oxidation behavior and modulates iron oxide phase transition process.Sn addition significantly reduces the depth of grain boundaries oxidation and the area of internal oxidation,as well as retards the process of oxide scale transformation.Sn preferentially segregates at the iron oxide/substrate interface,forming a diffusion barrier that suppresses outward diffusion of alloying elements and inward oxygen transport.Concurrently,Sn enrichment at grain boundaries obstructs short-circuit oxygen diffusion pathways,significantly reducing the depth of oxidation at the grain boundaries.Furthermore,Sn segregation decreases the interfacial oxygen chemical potential and oxygen availability for selective oxidation reaction.The strategic incorporation of surface-active elements has emerged as a viable metallurgical approach to reduce internal oxidation in hot-rolled coils for AHSS applications. 展开更多
关键词 Sn microalloying Interface segregation oxidation kinetics Grain boundaries oxidation Hot-rolled coil
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Preparation and antioxidant application of TEMPO-oxidized flaxseed cellulose nanofibers gel films
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作者 Huojiao Gan Yan Li +5 位作者 Mingkai Sun Yashu Chen Dengfeng Peng Xiaogang Luo Hu Tang Qianchun Deng 《Oil Crop Science》 2026年第1期66-73,共8页
As the pace of urban life accelerates,plastic wrap has become an everyday necessity.However,traditional petroleum-based plastic wrap is difficult to degrade and prone to releasing harmful plasticizers.Therefore,develo... As the pace of urban life accelerates,plastic wrap has become an everyday necessity.However,traditional petroleum-based plastic wrap is difficult to degrade and prone to releasing harmful plasticizers.Therefore,developing sustainable,biodegradable,and high-performance alternative materials is crucial.Inspired by the cellulose-gum reinforcement mechanism in flaxseed hulls,this study utilized flaxseed hulls as raw material.Through hot water washing,alkali boiling,and bleaching,high-purity insoluble cellulose(FC)was extracted.Subsequently,flaxseed hull cellulose nanofibers(FCN)were prepared via TEMPO oxidation and ultrasonic treatment.Using FC and FCN,an all-natural cellulose-flaxseed gum composite membrane(CM)was constructed,where FCN serves as the framework and flaxseed gum acts as the binder,forming a dense structure.This composite membrane demonstrated effectiveness in nut preservation,significantly delaying nut oxidation and providing a viable pathway for sustainable food packaging. 展开更多
关键词 CELLULOSE NANOFIBERS antioxidant preservation Food packaging Sustainability
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Study on the Extraction of Flavonoids from Hylocereus undatus(Haw.)Britton&Rose and Their Antioxidant Activity
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作者 Zhao LIU Deyun MA +1 位作者 Rimeng CHEN Meijiao MO 《Agricultural Biotechnology》 2026年第1期65-69,共5页
[Objectives]This study was conducted to investigate the extraction process,content determination,and antioxidant properties of flavonoids from Hylocereus undatus(Haw.)Britton&Rose.[Methods]Using H.undatus as the r... [Objectives]This study was conducted to investigate the extraction process,content determination,and antioxidant properties of flavonoids from Hylocereus undatus(Haw.)Britton&Rose.[Methods]Using H.undatus as the raw material,the effects of ethanol concentration,ultrasonic temperature,time,and solid-to-liquid ratio on the total flavonoid yield were investigated through single-factor and orthogonal experiments.[Results]All factors had a significant effect on the yield.The optimized conditions were determined as follows:ethanol concentration 75%,ultrasonic temperature 60℃,ultrasonic time 30 min,and solid-to-liquid ratio 1:50(g/ml).Under these conditions,the total flavonoid yield reached 3.08%.Evaluation of antioxidant activity revealed that the extract exhibited superior scavenging rates against both DPPH and hydroxyl radicals compared with the standard reference compound BHT.[Conclusions]This study holds significant importance for elucidating the pharmacological mechanisms of flavonoids in H.undatus and for expanding their application in medicine and health products. 展开更多
关键词 Hylocereus undatus FLAVONOIDS antioxidant activity
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Exogenous myo-inositol alleviates abiotic stress in rapeseed by modulating ion homeostasis and antioxidant defense
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作者 Shihang Fan Xulong Zhao +4 位作者 Nian Liu Xiang Ji Zihong Huang Wei Hua Zhengwei Fu 《Oil Crop Science》 2026年第1期55-65,共11页
Soil salinization is a major abiotic stress that severely constrains global agricultural productivity.The application of exogenous bioactive substances represents a promising strategy to enhance crop salt tolerance.In... Soil salinization is a major abiotic stress that severely constrains global agricultural productivity.The application of exogenous bioactive substances represents a promising strategy to enhance crop salt tolerance.In this study,we investigated the protective role of exogenous myo-inositol in rapeseed under salinity stress.Here,we demonstrated that exogenous application of 20μM myo-inositol significantly alleviates salt stress in rapeseed seedlings.Myo-inositol effectively mitigated growth inhibition,maintained chlorophyll levels and photosynthetic activity,and stabilized membrane integrity under salt stress.Physiological and molecular evidence indicated that myo-inositol activates the antioxidant system by enhancing the activities of superoxide dismutase(SOD),peroxidase(POD),and catalase(CAT),thereby reducing reactive oxygen species accumulation.Notably,myoinositol triggered a species-specific ion homeostasis strategy by increasing Na+accumulation,associated with the upregulation of BnHKT1 and downregulation of vacuolar BnNHX homologs.Concurrently,myo-inositol stimulated proline biosynthesis for osmotic adjustment.Furthermore,qRT-PCR analysis showed that myo-inositol finetunes the expression of key genes involved in antioxidant defense,osmotic adjustment,and stress signaling.These findings demonstrate that myo-inositol enhances rapeseed salt tolerance through an integrated mechanism involving antioxidant activation,transcriptional reprogramming,and a species-specific ion homeostasis strategy,establishing its potential as an effective biostimulant for saline agriculture. 展开更多
关键词 RAPESEED MYO-INOSITOL Salt stress Ion homeostasis antioxidant defense
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Structural evolution, chemical and antioxidant properties of pectic polysaccharides from sesame hull roasted at various temperatures
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作者 Jinyuan Hu Xu Fang +6 位作者 Huixian Guo Rui Wang Wenting Yin Xiaoshuang Cai Huamin Liu Xinliang Zhu Xuede Wang 《Grain & Oil Science and Technology》 2026年第1期21-29,共9页
Roasting constitutes a critical stage in sesame oil production,where the thermal degradation of pectic polysaccharide initiates fundamental chemical transformations including caramelization,Maillard processes,lipid ox... Roasting constitutes a critical stage in sesame oil production,where the thermal degradation of pectic polysaccharide initiates fundamental chemical transformations including caramelization,Maillard processes,lipid oxidation and Strecker degradation.This study systematically examines the structural,chemical and oil antioxidant capacity of sesame hull-derived pectic polysaccharides(URA and URB)under 160–220℃,and their impacts on sesame oil oxidative stability.The results demonstrate temperature-dependent molecular restructuring of URA and URB with molecular weights increasing proportionally and reduced total yields by 42.73%until 220℃.Furfural and organic acids were identified as primary pyrolysis products,accompanied by volatile aromatic compounds including furans,benzenes,and phenols.Sesame oil with the mixture of URA and URB(HSO-URA/B)exhibited optimal thermal antioxidant performance,demonstrating improved sesame oil oxidative stability as evidenced by peroxide value(0.07–0.81 g/100 g)and oxidative stability index(22.6 h).This work provides a scientific foundation for optimizing sesame oil quality while transforming hull byproducts into valueadded food ingredients. 展开更多
关键词 Sesame hull Pectic polysaccharides antioxidant capacity ROASTING DEGRADATION
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