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Molecular Mechanism and Molecular Design of Lubricating Oil Antioxidants 被引量:1
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作者 Su Shuo Long Jun +2 位作者 Duan Qinghua Zhou Han Zhao Yi 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第2期135-145,共11页
To overcome the limitations of traditional experimental“trial and error”methods in lubricant additive design,a new molecular design method based on molecular structure parameters is established here.The molecular me... To overcome the limitations of traditional experimental“trial and error”methods in lubricant additive design,a new molecular design method based on molecular structure parameters is established here.The molecular mechanism of the antioxidant reaction of hindered phenol,diphenylamine,and alkyl sulfide are studied via molecular simulations.Calculation results show that the strong electron-donating ability and high hydrogen-donating activity of the antioxidant molecule and the low hydrogen-abstracting activity of free radicals formed after dehydrogenation are the internal molecular causes of the shielding of phenol and diphenylamine from scavenging peroxy free radicals,and the strong electron-donating ability is the internal molecular cause of the high activity of thioether in decomposing alkyl hydrogen peroxide.Based on this antioxidant molecular mechanism,a molecular design rule of antioxidant is proposed,namely“high EHOMO,large Q(S),low bond dissociation energy BDE(O—H)and BDE(N—H)”.Two new antioxidants,PAS-I and PAS-II,are designed and prepared by chemical bonding of hindered phenol,diphenylamine,and sulfur atoms.Experimental results show that these antioxidants both have excellent antioxidant effects in lubricating oil,and that PAS-II is the superior antioxidant,consistent with theoretical predictions. 展开更多
关键词 lubricating oil antioxidant molecular mechanism molecular design antioxidant performance
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Studies of antioxidant performance of amine additives in lubricating oil using 3D-QSAR 被引量:1
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作者 ZHAN ShengPeng DUAN HaiTao +6 位作者 HUA Meng XU HaiPing SHANG HongFei JIN YongLiang JIA Dan TU JieSong LI Jian 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2017年第2期299-305,共7页
Available model of 3D-quantitative structure-activity relationship (3D-QSAR, the method of TopomerCoMFA) has been used to establish relationship between antioxidant performances of lubricating oil (trimethylolpropane ... Available model of 3D-quantitative structure-activity relationship (3D-QSAR, the method of TopomerCoMFA) has been used to establish relationship between antioxidant performances of lubricating oil (trimethylolpropane trioleate, TMPTO) with 15 kinds of amine additives and its molecular structure. Correlation coefficient of the cross-validation (include internal q2 and external qpred 2 ) and conventional correlation coefficient showed the model to be both stable and good predictive. The electron-donating group and larger steric effects group are adopted at the para-position or meta-position of amido on the benzene ring, and suitably decreasing the branch chain near the para-position, these indicate that the antioxidant performance of amine additives can be enhanced. The results not only can help us understanding the rule of antioxidant performance, but also providing guidance(s) to predict antioxidant performance of existing amine additives and to design or modify new amine additives in lubricating oil. 展开更多
关键词 QSAR amine additive TopomerCoMFA antioxidant performance LUBRICATION
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Effects of soybean meal replacement with fermented alfalfa meal on the growth performance,serum antioxidant functions,digestive enzyme activities,and cecal microflora of geese 被引量:6
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作者 YIN Hai-cheng HUANG Jin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第9期2077-2086,共10页
Fermented forages are important feedstuffs. Bacillus subtilis inoculants are often used to improve the value of forage legume fermentation. The present work was conducted to study the effects of replacing soybean meal... Fermented forages are important feedstuffs. Bacillus subtilis inoculants are often used to improve the value of forage legume fermentation. The present work was conducted to study the effects of replacing soybean meal with solid-state fermented alfalfa meal(FAM) with B. subtilis ACCC 01746 on growth performance, serum antioxidant and digestive enzyme activities, and cecal microflora in goose. 300 healthy geese with similar body weights were randomly assigned to six treatment groups with five replicates of 10 geese(five males and five females) each. Geese were fed ad libitum for 35 days. Results showed that the geese fed with 4 and 8% FAM exhibited no significant effects on their final body weights(FBW) and average day gain(ADG)(P〉0.05), whereas 12% or higher FAM caused poor growth of the geese compared with control diet(linear(L): P〈0.05). The average daily feed intake(ADFI)(quadratic(Q): P〈0.05) and feed conversion ratio(FCR)(L: P〈0.05) with 8% or higher supplementation level were higher than those of the control group. The activities of antioxidant enzyme in serum increased, and the level of malondialdehyde(MDA) significantly decreased with increasing dietary FAM level(L: P〈0.05). However, no significant differences were observed at 8% or lower supplementation level for glutathione peroxidase(GSH-Px) and superoxide dismutase(SOD)(P〉0.05) and at 4% for catalase(CAT) supplementation level compared with the control group. All diets containing FAM increased digestive enzyme activities in geese. However, geese fed diets with 12% FAM supplementation showed the highest trypsin activities in pancreas(Q: P〈0.05). Supplementation with 12% or higher FAM significantly increased amylase activities in pancreas(L: P〈0.05) and duodenum(L: P〈0.05) compared with the control group. Significant differences were not observed in total anaerobic bacteria between geese fed with FAM and control diets on day 35(P〉0.05). The numbers of Bifidobacterium and Lactobacillus in the cecum of geese fed with FAM significantly increased(L: P〈0.05), but no significant effects were found with 4 and 8% FAM supplementation levels compared with the control(P〉0.05). By contrast, the coliform counts of cecum decreased with increasing inclusion of FAM, but these counts were significantly reduced in geese fed diets with 12% or higher FAM supplementation level(L: P〈0.05). Collectively, our results indicated that supplementation of the basal geese diet with 8% FAM had no apparent adverse effects on growth performance, serum antioxidant enzyme activities, and digestive parameters and beneficial microbiota. 展开更多
关键词 fermented alfalfa meal geese growth performance serum antioxidant enzyme digestive enzyme cecal microflora
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Effect of dietary supplementation with flavonoid from Scutellaria baicalensis Georgi on growth performance,meat quality and antioxidative ability of broilers 被引量:9
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作者 LIAO Xiu-dong WEN Qian +3 位作者 ZHANG Ling-yan LU Lin ZHANG Li-yang LUO Xu-gang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第5期1165-1170,共6页
An experiment was conducted to investigate the effect of dietary supplementation with flavonoid from Scutellaria baicalensis Georgi(SBGFN) as SBGFN-zinc(SBGFN-Zn) on growth performance, meat quality, immune respon... An experiment was conducted to investigate the effect of dietary supplementation with flavonoid from Scutellaria baicalensis Georgi(SBGFN) as SBGFN-zinc(SBGFN-Zn) on growth performance, meat quality, immune responses and antioxidation of broilers. A total of 450 one-d-old Arbor Acres male broilers were randomly allocated to 5 treatments with 6 replicates of 15 birds per replicate for each treatment in a completely randomized design. Birds were fed a SBGFN-unsupplemented cornsoybean meal basal diet(control) or the basal diet supplemented with 60, 120, 180 or 240 mg SBGFN kg-(–1) from SBGFN-Zn for 42 d. Dietary SBGFN supplementation affected(P〈0.03) drip loss in thigh muscle, total superoxide dismutase(T-SOD) and glutathione peroxidase(GSH-Px) activity in liver of broilers at 42 d of age. Chicks fed the diets supplemented with 120, 180 and 240 mg SBGFN kg-(–1) had lower(P〈0.03) drip loss of thigh muscle than those fed the control diet. Chicks fed the diet supplemented with 180 mg SBGFN kg-(–1) had higher(P〈0.03) liver T-SOD and GSH-Px activity than those fed the diets supplemented with 0, 60 and 120 mg SBGFN kg-(–1). The results from the present study indicate that dietary supplementation with 180 mg SBGFN kg-(–1) as SBGFN-Zn improved both meat quality and antioxidative ability of broilers. 展开更多
关键词 flavonoid growth performance meat quality antioxidation
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Single source precursor derived SiBCNHf ceramic with enhanced high-temperature microwave absorption and antioxidation 被引量:3
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作者 Yan Song Ziyu Liu +5 位作者 Xicheng Zhang Runqiu Zhu Youwei Zhang Pinggui Liu Lihua He Jie Kong 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2022年第31期215-227,共13页
Electromagnetic(EM)wave-absorbing materials with high-temperature-resistance are urgently desirable to eliminate EM interference in extreme conditions.Precursor derived ceramics(PDC)route is being evolved as an effect... Electromagnetic(EM)wave-absorbing materials with high-temperature-resistance are urgently desirable to eliminate EM interference in extreme conditions.Precursor derived ceramics(PDC)route is being evolved as an effective strategy to solve the puzzle.Herein,a single source hyperbranched polyborosi-lazane precursor containing hafnium(hb-PBSZ-Hf)is introduced and the SiBCNHf ceramic is obtained by further pyrolysis.The micro-sized tissues including HfC,SiC,HfB 2 nanocrystals and segregated carbons are in situ generated during annealing which not only increase EM wave absorption ability(minimum re-flection coefficient(RC_(min))is-56.71 dB with a thickness of 2.5 mm,effective absorption bandwidth(EAB)is 3.4 GHz),but also improve antioxidation property(less than 2 wt.%mass fluctuation at 1400℃in air).Theoretical simulation of complex permittivity suggests that SiBCNHf ceramic has an RC_(min)of less than-5 dB for the whole X-band even at 1100℃.Such SiBCNHf ceramic with superior high-temperature-resistance and antioxidation performance derived from single source precursors possesses great potential for EM wave absorbing coatings in high-temperature and harsh environments. 展开更多
关键词 hb-PBSZ-Hf precursor SiBCNHf ceramic EM wave absorption Antioxidation performance
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Natural product curcumin-based coordination nanoparticles for treating osteoarthritis via targeting Nrf2 and blocking NLRP3 inflammasome 被引量:3
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作者 Zhiqiang Zhou Fei Gong +6 位作者 Peng Zhang Xiaotong Wang Rui Zhang Wei Xia Xiang Gao Xiaozhong Zhou Liang Cheng 《Nano Research》 SCIE EI CSCD 2022年第4期3338-3345,共8页
Oxidative stress leads to chondrocyte apoptosis and extracellular matrix(ECM)degradation,thus contributing to the pathogenesis of osteoarthritis(OA).Herein,curcumin with remarkable antioxidant and anti-inflammatory ac... Oxidative stress leads to chondrocyte apoptosis and extracellular matrix(ECM)degradation,thus contributing to the pathogenesis of osteoarthritis(OA).Herein,curcumin with remarkable antioxidant and anti-inflammatory activities has been employed as an organic ligand to coordinate ferric ions for enhancing the water-solubility and biocompatibility of natural product curcumin.The obtained iron-curcumin-based coordination nanoparticles(Fe-Cur NPs)exhibit great water-solubility and efficient reactive oxygen/nitrogen species(ROS/RNS)scavenging ability.In vitro chondrocyte evaluation experiments indicated that the intracellular ROS/RNS induced by interleukin 1β(IL-1β)could be efficiently scavenged by these Fe-Cur NPs and oxidative-stressinduced cell death could be preserved as well.In addition,post intra-articular(i.a.)injection into OA rat joints,Fe-Cur NPs could greatly inhibit OA progression via activating the nuclear factor-erythroid 2 related factor-2(Nrf2)and inhibiting nod-like receptor protein-3(NLRP3)inflammasome activation in primary rat chondrocytes,as well as decrease the production of matrix degrading proteases and other inflammatory mediators.The efficient antioxidation and anti-inflammation performance of Fe-Cur NPs endow them as a promising nanoplatform for treatment of various inflammatory diseases,and more detailed researches will be conducted in the future. 展开更多
关键词 iron-curcumin-based coordination nanoparticles(Fe-Cur NPs) reactive oxygen/nitrogen species(ROS/RNS)scavenging ability OSTEOARTHRITIS antioxidation and anti-inflammation performance signaling pathway
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