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Bio-Based Waterborne Poly(Vanillin-Butyl Acrylate)/MXene Coatings for Leather with Desired Warmth Retention and Antibacterial Properties 被引量:1
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作者 Jianzhong Ma Li Ma +3 位作者 Lei Zhang Wenbo Zhang Qianqian Fan Buxing Han 《Engineering》 SCIE EI CAS CSCD 2024年第5期250-263,共14页
This study presents a solvent-free,facile synthesis of a bio-based green antibacterial agent and aromatic monomer methacrylated vanillin(MV)using vanillin.The resulting MV not only imparted antibacterial properties to... This study presents a solvent-free,facile synthesis of a bio-based green antibacterial agent and aromatic monomer methacrylated vanillin(MV)using vanillin.The resulting MV not only imparted antibacterial properties to coatings layered on leather,but could also be employed as a green alternative to petroleum-based carcinogen styrene(St).Herein,MV was copolymerized with butyl acrylate(BA)to obtain waterborne bio-based P(MV-BA)miniemulsion via miniemulsion polymerization.Subsequently,MXene nanosheets with excellent photothermal conversion performance and antibacterial properties,were introduced into the P(MV-BA)miniemulsion by ultrasonic dispersion.During the gradual solidification of P(MV-BA)/MXene nanocomposite miniemulsion on the leather surface,MXene gradually migrated to the surface of leather coatings due to the cavitation effect of ultrasonication and amphiphilicity of MXene,which prompted its full exposure to light and bacteria,exerting the maximum photothermal conversion efficiency and significant antibacterial efficacy.In particular,when the dosage of MXene nanosheets was 1.4 wt%,the surface temperature of P(MV-BA)/MXene nanocomposite miniemulsioncoated leather(PML)increased by about 15℃ in an outdoor environment during winter,and the antibacterial rate against Escherichia coli and Staphylococcus aureus was nearly 100%under the simulated sunlight treatment for 30 min.Moreover,the introduction of MXene nanosheets increased the air permeability,water vapor permeability,and thermal stability of these coatings.This study provides a new insight into the preparation of novel,green,and waterborne bio-based nanocomposite coatings for leather,with desired warmth retention and antibacterial properties.It can not only realize zerocarbon heating based on sunlight in winter,reducing the use of fossil fuels and greenhouse gas emissions,but also improve ability to fight off invasion by harmful bacteria,viruses,and other microorganisms. 展开更多
关键词 MXene nanosheets vanillin Styrene substitute Leather coating Photothermal conversion Warmth retention Antibacterial properties
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Vanillin Based Polymers:VI.Poly(hydrovanilloin-furfural)and Poly(hydrovanilloin-5-hydroxymethylfurfural)
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作者 Ananda S.Amarasekara Gabriel Murillo Morales Raghava R.Kommalapati 《Journal of Renewable Materials》 EI CAS 2024年第9期1495-1506,共12页
Renewable resources based polymers provides a sustainable alternative to petroleum derived polymeric materials.As a part of our series on synthesis of vanillin based renewable polymers,we report the synthesis of poly(... Renewable resources based polymers provides a sustainable alternative to petroleum derived polymeric materials.As a part of our series on synthesis of vanillin based renewable polymers,we report the synthesis of poly(hydrovanilloin-furfural)[poly(HVL-Fur)]and poly(hydrovanilloin–5-hydromethylfurfural)[poly(HVL-5-HMF)].Vanillin was dimerized to a mixtures of meso/DL-hydrovanilloins with 94%meso product by electrochemical reductive coupling in aqueous sodium hydroxide using lead electrodes in quantitative yield.Then sodium hydroxide catalyzed condensation of hydrovanilloin with furfural in water at 80℃for 72 h was used to synthesize poly(HVL-Fur)with Mw=8600 g mol^(−1),PDI=1.28 in 78%yield.Similarly,condensation of hydrovanilloin with 5-hydroxymethylfurfural at 80℃for 48 h produced poly(HVL-5-HMF)with Mw=12,100 g mol−1,PDI=1.27 in 68%yield.poly(HVL-Fur)and poly(HVL-5-HMF)showed similar Tg values of 59℃and 60℃,respectively;whereas melting behaviors are dissimilar with Tm 171℃–173℃and 148℃–182℃,respectively. 展开更多
关键词 vanillin hydrovanilloin FURFURAL 5-HYDROXYMETHYLFURFURAL renewable polymers
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Vanillin吸嗅对抑郁模型SD大鼠血清Mg^(2+)的影响 被引量:2
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作者 许慧 刘扬 +2 位作者 王艳梅 徐金勇 李光武 《中风与神经疾病杂志》 CAS CSCD 北大核心 2013年第11期993-996,共4页
目的探讨嗅质香兰素(Vanillin)吸嗅对SD大鼠抑郁样行为的调节作用及可能的作用机制。方法雄性SD大鼠70只,采用CUMS+孤养或嗅球毁损,制备抑郁样模型,符合模型大鼠随机分为Vanillin吸嗅组、氟西汀组、模型组、嗅球毁损+Vanillin吸嗅组及... 目的探讨嗅质香兰素(Vanillin)吸嗅对SD大鼠抑郁样行为的调节作用及可能的作用机制。方法雄性SD大鼠70只,采用CUMS+孤养或嗅球毁损,制备抑郁样模型,符合模型大鼠随机分为Vanillin吸嗅组、氟西汀组、模型组、嗅球毁损+Vanillin吸嗅组及假手术组。评价大鼠干预后各时间点的神经行为学变化及血清Mg2+含量。结果 (Vanillin吸嗅组干预2w后强迫游泳实验时间明显缩短(P<0.05);24h糖水消耗量实验明显增加(P<0.05);5w后旷野实验自主活动次数增加(P<0.05);血清Mg2+含量明显提高(P<0.05)。结论 Vanillin吸嗅可以缓解抑郁模型大鼠的抑郁样行为,其机制可能是提高血清Mg2+含量,通过Mg2+调控HPA轴,影响海马、杏仁核情绪中枢活动,从而达到防治抑郁症的作用。 展开更多
关键词 vanillin 嗅觉通路 抑郁症 Mg2+
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Synthesis and Purification of Porphyrin-Schiff Base Using Ethyl Vanillin 被引量:11
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作者 WANG Dong SU Lian-jiang +2 位作者 CHENG Xiu-li SUN Er-jun SHI Tong-shun 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2007年第2期135-137,共3页
A novel porphyrin-Schiff base was synthesized via the condensation of 5-(4-aminophenyl) -10,15,20-triphenylperphyrin and ethyl vanillin. After analyzing the level of purification of the perphyrin-Schiff base, it was... A novel porphyrin-Schiff base was synthesized via the condensation of 5-(4-aminophenyl) -10,15,20-triphenylperphyrin and ethyl vanillin. After analyzing the level of purification of the perphyrin-Schiff base, it was successfully separated. This perphyrin-Schiff base was characterized by using UV-Vis, IR,^1H NMR and MS spectroscopy. 展开更多
关键词 SYNTHESIS Porphyrin-Schiff base Ethyl vanillin PURIFICATION
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Isolation and identification of fungi found in contaminated fermented milk and antifungal activity of vanillin 被引量:3
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作者 Xu Pei Mekonen Tekliye Mingsheng Dong 《Food Science and Human Wellness》 SCIE 2021年第2期214-220,共7页
Fungi contamination is an important factor affecting the quality and commercial value of fermented milk.Vanillin is known as a safe and efficient natural antimicrobial additive with great potential value as a food bio... Fungi contamination is an important factor affecting the quality and commercial value of fermented milk.Vanillin is known as a safe and efficient natural antimicrobial additive with great potential value as a food bio-preservative.In this study,the microbiological quality of fermented milk of different brands retailed in China and the antimicrobial activity of vanillin were investigated.A total of 27 fermented milk samples were purchased and evaluated.Fungal isolates obtained were characterized by DNA sequencing of the internal transcribed spacer(ITS)region.The effects of vanillin on the growth of fungi were studied by plate dilution method,radical colony diameter,and mycelium biomass.The result showed that 14.8%of the samples were contaminated with three different species of fungi with Cladosporium spp.being the most predominant fungal contaminant.The study further showed that vanillin had significant inhibitory activity against the growth of the fungi species.The cell number,radical colony diameter,and the mycelium biomass of the fungal contaminant were significantly reduced by the inhibitory action of the vanillin.The study thus provides reliable data evidence that will help relevant stakeholders in the fermented milk industries to improve their quality control strategies and consider vanillin as a bio-preservative with the potential to increase the shelf-life and safety of fermented milk. 展开更多
关键词 Fermented milk FungiInternal transcribed spacer vanillin Antimicrobial activity
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A Vanillin-Derived,DOPO-Contained Bisphenol as a Reactive Flame Retardant for High-Performance Epoxy Thermosets 被引量:2
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作者 Li Wang Rongbai Tong +4 位作者 Juanli Wang Jintao Wan Yuhu Li Pujun Jin Daodao Hu 《Journal of Renewable Materials》 SCIE EI 2022年第5期1349-1364,共16页
Quest for bio-based halogen-free green flame retardant has attracted many concerns in recent years.Herein a reactive functional flame retardant containing phosphorus VDP is synthesized from vanillin,9,10-dihydro-9-oxa... Quest for bio-based halogen-free green flame retardant has attracted many concerns in recent years.Herein a reactive functional flame retardant containing phosphorus VDP is synthesized from vanillin,9,10-dihydro-9-oxa-10-phosphophene-10-oxide(DOPO)and phenol via a facile way.VDP is characterized with^(1)H NMR,^(31)P NMR,FTIR and Time of Flight Mass Spectrometry,and used as a new reactive flame retardant for bisphenol epoxy thermosets.Thermogravimetry analysis shows that when the VDP loading is only 0.5P%(based on phosphorus content),the residue increases from 14.2%to 21.1%at 750℃ in N_(2)compare with neat DGEBA.Correspondingly,the limit oxygen index increased to 29.6%,and flame retardancy reaches UL-94 V0 grade.Micro combustion calorimetry(MCC)and cone calorimetry analyses demonstrate that VDP can significantly lower flammability of the epoxy thermoset.With only 0.5P%of VDP,the heat release rate,total heat release rate and smoke production are reduced markedly.At the same time,the mechanical properties of the modified epoxy thermosets are also improved.The impact strength increases by 34%and the flexural strength increased by 23%,with 1.5P%of VDP.In short,VDP not only improves the flame retardancy,but also improves the mechanical properties of the epoxy thermosets. 展开更多
关键词 Epoxy resin bio-based flame retardant vanillin properties of thermosets
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Vanillin and its derivatives,potential promising antifungal agents,inhibit Aspergillus flavus spores via destroying the integrity of cell membrane rather than cell wall 被引量:7
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作者 Qian Li Xiaoman Zhu 《Grain & Oil Science and Technology》 2021年第2期54-61,共8页
To study the structure-antifungal activity of vanillin against Aspergillus flavus(A.flavus),the susceptibilities of A.flavus to vanillin and its isomers(o-vanillin,2-hydroxy-4-methoxybenzaldehyde(HMB),2-hydroxy-5-meth... To study the structure-antifungal activity of vanillin against Aspergillus flavus(A.flavus),the susceptibilities of A.flavus to vanillin and its isomers(o-vanillin,2-hydroxy-4-methoxybenzaldehyde(HMB),2-hydroxy-5-methoxybenzaldehyde)and the possible antifungal mechanisms have been investigated.All the four volatile aldehydes could inhibit the germination of spores,and the minimum inhibitory concentrations(MICs)of them were in this order:vanillin(200μg/mL),o-vanillin(100μg/mL),2-hydroxy-5-methoxybenzaldehyde(100μg/mL),HMB(70μg/mL).The minimum fungicidal concentrations(MFCs)of them were in this order:vanillin(240μg/mL),o-vanillin(160μg/mL),HMB(140μg/mL),2-hydroxy-5-methoxybenzaldehyde(140μg/mL).Spore size was arrested at 0 h with the treatment of the four volatile aldehydes.Effects of the four volatile aldehydes on the cell wall and cell membrane integrity of A flavus were observed by calcofluor white(CW)staining and propidium iodide(PI)staining.The results showed that HMB exerted the strongest antifungal and fungicidal effects on the growth of A.flavus.The four volatile aldehydes had little influence on cell wall integrity after 3-hour treatment,however,they could strongly damage the cell membrane integrity.All the four volatile aldehydes could effectively prevent the growth of A.flavus on peanut seeds.The antifungal mechanisms of the four volatile aldehydes provide theoretical foundations for their development of new antifungal agents. 展开更多
关键词 Aspergillus flavus vanillin O-vanillin HMB 2-Hydroxy-5-methoxybenzaldehyde Antifungal mechanism
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COL1A1突变致Van der Hoeve综合征家系的遗传和表型分析并文献复习
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作者 聂泽群 贺楚峰 +6 位作者 吴宏 凌捷 付秦辉 庞博 张帅 陈永嘉 梅凌云 《听力学及言语疾病杂志》 CAS CSCD 北大核心 2024年第5期389-393,共5页
目的对一个常染色体显性遗传的Van der Hoeve综合征家系进行详尽的临床表型分析及基因突变检测,明确该家系的致病基因突变位点及该突变对基因编码的影响。方法对收集到的Van der Hoeve综合征家系进行包括病史、体格检查及辅助检查在内... 目的对一个常染色体显性遗传的Van der Hoeve综合征家系进行详尽的临床表型分析及基因突变检测,明确该家系的致病基因突变位点及该突变对基因编码的影响。方法对收集到的Van der Hoeve综合征家系进行包括病史、体格检查及辅助检查在内的临床资料的收集及外周血液样本的采集,并对22位家系成员进行外显子组测序以及Sanger测序,利用生物信息学软件分析数据。结果该家系共五代,各代连续发病,且每一代男女均可患病,符合常染色体显性遗传特点。该家系中12例患者均自出生时巩膜即呈蓝色且身材矮小,8例患者有骨折病史,可正常愈合,3例患者考虑有Van der Hoeve综合征所致的听力下降,12例患者的COL1A1基因第17号外显子有一个碱基的缺失(c.1128delT),使第376位后的氨基酸编码改变,在第539位提前结束氨基酸编码,该家系中10例无症状者无此突变。结论该家系患者确定为由COL1A1基因c.1128delT突变导致的Van der Hoeve综合征。 展开更多
关键词 van der Hoeve综合征 成骨不全 COL1A1基因 基因突变
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Crystal Structures of O-Vanillin-semicarbazide and Salicylaldehyde-semicarbazide 被引量:3
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作者 Li Shu-Lan Liu De-Xin +1 位作者 Zhou Jian-Hua Meng Fan-Qin(Department of Chemistry, Shandong University, Jinan, 250100) 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1995年第2期88-93,共6页
o-Vanillin-semicarbazide C_9H_(11) N_3O_3, written simply as cpl, M_r= 209. 21 is a yellow crystal. Cp1 crystallizes in the monoclinic space group P2_1/a with unit cell parameters: a= 6. 596(6) , b=20. 534(6) , c=7. 1... o-Vanillin-semicarbazide C_9H_(11) N_3O_3, written simply as cpl, M_r= 209. 21 is a yellow crystal. Cp1 crystallizes in the monoclinic space group P2_1/a with unit cell parameters: a= 6. 596(6) , b=20. 534(6) , c=7. 108(6) , β=99.00(8)°,Z=4, D_c=1. 46 g/cm ̄3, V=951 , μ=1. 05cm ̄(-1), F(000)=440, R=0. 058, R_w =0. 056. Salicylaldehyde-semicarbazide C_8H_9N_3O_2, written simply as cp2, M_r=179.18 is a colorless crystal. cp2 crystallizes in the triclinic space group P1 with a= 5.276 (3), b=7. 116(4) , c=24. 286(3), a=86. 72(3) ,β=83. 99(3),γ=68.22(5) °,Z=4 , D_c=1. 41 g/cm ̄3, V=841.9,μ=0. 98 cm  ̄(-1),F (000)=376, R=0.066,R_w= 0. 067. The dihedral angle between plane 1 formed by benzene ring and plane 2 by N(2) , C(2), N(3), and O(3) is 161.40°for cp1, while the angle between plane 3 made by benzene ring (or benzene ring in the other molecule)and plane 4 by N(2) , C (18) , N(3) and O(3) For N(5),C(28) , O(4) , and N(6)]is 15. 07°(or 15. 15°) for cp2. The temperature of the thermodecomposition of cp1 is higher than that of cp2. 展开更多
关键词 crystal structure o-vanillin-semicarbazide salicylaldehyde-semicarbazide
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Syntheses,Crystal Structures and Kinetic Mechanisms of Thermal Decomposition of Rare Earth Complexes with Schiff Base Derived from o-Vanillin and p-Toluidine 被引量:5
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作者 赵国良 冯云龙 温一航 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第3期268-275,共8页
Three complexes, [Pr(NO3)3(HL)2] (1), [Nd(NO3)3(HL)2] (2) and [Er(NO3)3(HL)2] ·0.5H2O (3), were synthesized from the reaction of a Schiff base ligand 2-[ (4-methylphenylimino)methyl ]-6-methox... Three complexes, [Pr(NO3)3(HL)2] (1), [Nd(NO3)3(HL)2] (2) and [Er(NO3)3(HL)2] ·0.5H2O (3), were synthesized from the reaction of a Schiff base ligand 2-[ (4-methylphenylimino)methyl ]-6-methoxyphenol (C15 H15 NO2, HL) with Ln(NO3)3·6H2O (Ln = Pr, Nd, Er). Characterization by single-crystal X-ray diffraction technique, elemental analysis, molar conductance, FT-IR, UV-Vis, ^1H NMR and thermal analysis shows the title complexes are neutral molecules where the central Ln( Ⅲ) ion is ten-coordinated in biapical anti-hexahedron prism geometry, with four oxygen atoms of the phenolic hydroxy and methoxy groups in the two bidentate Schiff base ligands and six oxygen atoms provided by the three bidentate NO3 - anions. Additionally, the kinetic mechanism of thermal decomposition of complex 3 was determined with a TG-DTG curves by both integral and differential methods. The functions of thermal decomposition reaction mechanism and the equation of kinetic compensation effect were obtained. 展开更多
关键词 O-vanillin P-TOLUIDINE Schiff base crystal structure kinetic mechanism of thermal decomposition rare earths
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Syntheses, Characterizations, Crystal Structures and Antibacterial Activities of Two Zinc(II) Complexes with a Schiff Base Derived from o-Vanillin and p-Toluidine 被引量:3
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作者 余玉叶 赵国良 温一航 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第12期1395-1402,共8页
Two new zinc(Ⅱ) complexes, [Zn2L2Ch].2[ZnL(CH3OH)Cl2] 1 and [ZnL2(NO3)2] 2, were synthesized by reacting ZnX2.nH2O (X = Cl^-, NO3^-) and a Schiff base ligand 2-[(4-methylphenylimino)methyl]-6-methoxyphenol ... Two new zinc(Ⅱ) complexes, [Zn2L2Ch].2[ZnL(CH3OH)Cl2] 1 and [ZnL2(NO3)2] 2, were synthesized by reacting ZnX2.nH2O (X = Cl^-, NO3^-) and a Schiff base ligand 2-[(4-methylphenylimino)methyl]-6-methoxyphenol (C15HIsNO2, L) which was obtained by the condensation of o-vanillin (2-hydroxy-3-methoxybenzaldehyde) with p-toluidine. Both 1 and 2 were characterized by single-crystal X-ray diffraction technique, elemental analysis, molar conductance, FT-IR, UV-Vis, IH-NMR spectra and thermogravimetrie analysis. The Schiff base ligand and its zinc(Ⅱ) complexes have been tested in vitro to evaluate their antibacterial activity against bacteria, viz., Escherichia Coli, Staphylococcus aureus and Bacillus Subtilis. The results show that these complexes have higher activity than the corresponding free Schiff base ligand against the same bacteria. 展开更多
关键词 O-vanillin P-TOLUIDINE Schiff base zinc(Ⅱ) complex crystal structure antibacterial activities
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Synthesis of Vanillin 1, 2-Propylene Glycol Acetal Catalyzed by H3PMo6W6O40·nH2O 被引量:1
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作者 Zongrui Liu Zhe Dong Xiaohong Wang Lijuan Xie Limei Duan 《Journal of Chemistry and Chemical Engineering》 2010年第2期22-26,共5页
Vanillin 1, 2-propylene glycol acetal was synthesized from vanillin and 1, 2-propylene glycol using H3PMo6W6O40·nH2O as catalyst, The factors influencing the synthesis were discussed and the better reaction condi... Vanillin 1, 2-propylene glycol acetal was synthesized from vanillin and 1, 2-propylene glycol using H3PMo6W6O40·nH2O as catalyst, The factors influencing the synthesis were discussed and the better reaction conditions were found as follows: The amount of vanillin was 3.8 g, the molar ratio of vanillin was 1, 2-propylene glycol 1.0 to 2.4, the amount of catalyst was 1.6% in proportion to the total reacting materials, the volume ofcyclohexane as the water-carrying agent 4 mL, the refluxing time was 2 h at 88-96℃ and thus the product yield reached over 87%. The results show that the catalyst's activity is high and the reaction time is short. 展开更多
关键词 vanillin 1 2-propylene glycol acetal H3PMo6W6O40 polyoxometalate catalysis.
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Potassium Bromate-induced Changes in the Adult Mouse Cerebellum Are Ameliorated by Vanillin
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作者 Hajer Ben Saad Dorra Driss +8 位作者 Imen Jaballi Hanen Ghozzi Ons Boudawara Michael Droguet Christian Magne Monsef Nasri Khaled Mounir Zeghal Ahmed Hakim Ibtissem Ben Amara 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2018年第2期115-125,共11页
Objective The current study aimed to elucidate the effect of vanillin on behavioral changes, oxidative stress, and histopathological changes induced by potassium bromate (KBrO3), an environmental pollutant, in the c... Objective The current study aimed to elucidate the effect of vanillin on behavioral changes, oxidative stress, and histopathological changes induced by potassium bromate (KBrO3), an environmental pollutant, in the cerebellum of adult mice.Methods The animals were divided into four groups: group 1 served as a control, group 2 received KBrO3, group 3 received KBrO3 and vanillin, and group 4 received only vanillin. We then measured behavioral changes, oxidative stress, and molecular and histological changes in the cerebellum.Results We observed significant behavioral changes in KBrO3-exposed mice. When investigating redox homeostasis in the cerebellum, we found that mice treated with KBrO3 had increased lipid peroxidation and protein oxidation in the cerebellum. These effects were accompanied by decreased Na+-K+ and Mg2+ ATPase activity and antioxidant enzyme gene expression when compared to the control group. Additionally, there was a significant increase in cytokine gene expression in KBrO3-treated mice. Microscopy revealed that KBrO3 intoxication resulted in numerous degenerative changes in the cerebellum that were substantially ameliorated by vanillin supplementation. Co-administration of vanillin blocked the biochemical and molecular anomalies induced by KBrO3.Conclusion Our results demonstrate that vanillin is a potential therapeutic agent for oxidative stress associated with neurodegenerative diseases. 展开更多
关键词 CEREBELLUM Behavior Potassium bromate vanillin ATPASES Genes expression
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A Novel Spectrophotometric Method for Determination of Five 1,4-Dihydropyridine Drugs in Their Tablets and Capsules Using Vanillin Reagent
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作者 Mohamed A. El Hamd Sayed M. Derayea +1 位作者 Osama Hassan Abdelmageed Hassan F. Askal 《American Journal of Analytical Chemistry》 2013年第3期148-157,共10页
A selective and new spectrophotometric method is described for determination of five 1,4 dihydropyridine drugs (1,4- DHP);namely nifedipine (NIF), nicardipine (NIC), nimodipine (NIM), felodipine (FEL) and amlodipine (... A selective and new spectrophotometric method is described for determination of five 1,4 dihydropyridine drugs (1,4- DHP);namely nifedipine (NIF), nicardipine (NIC), nimodipine (NIM), felodipine (FEL) and amlodipine (AML). The method is based on a coupling reaction between the cited drugs and vanillin reagent in acidic condition. Under optimized conditions, the red coloured products were measured at 500 nm for NIF, NIC, NIM and FEL or at 479 nm for AML. Molar absorptivities were ranged from 0.575 × 104 - 1.065 × 104 l·mol-1·cm-1, Beer’s law was obeyed at 5 - 70 μg/mL concentration range and the limit of detection was ranged from 0.150 - 1.500 μg/mL. The proposed method was successfully extended to pharmaceutical preparations tablets and capsules and comparison by Student’s t-test and variance ratio F-test showed no significant difference. 展开更多
关键词 SPECTROPHOTOMETRIC Method 1 4-DHP Validated Selective vanillin REAGENT
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扩散张量成像定量联合改良Van Assche评分对肛瘘活动性的诊断价值
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作者 林杨皓 曾勇波 +2 位作者 罗绍杰 连永伟 宋亭 《影像诊断与介入放射学》 2024年第2期89-95,共7页
目的探讨扩散张量成像(DTI)定量联合改良Van Assche评分对肛瘘活动性的诊断价值。方法回顾性分析本院90例肛瘘患者临床、MR资料,分为活动性炎症(PIA)组和非活动性炎症(NIA)组,进行改良Van Assche评分。利用DTI测定主瘘管的各向异性分数(... 目的探讨扩散张量成像(DTI)定量联合改良Van Assche评分对肛瘘活动性的诊断价值。方法回顾性分析本院90例肛瘘患者临床、MR资料,分为活动性炎症(PIA)组和非活动性炎症(NIA)组,进行改良Van Assche评分。利用DTI测定主瘘管的各向异性分数(FA)值和表观扩散系数(ADC)值,比较两组改良Van Assche评分、瘘管FA值、ADC值是否存在差异,采用受试者工作特征(ROC)曲线,计算曲线下面积(AUC),利用DeLong检验,分析并比较Van Assche评分、DTI参数(FA值和ADC值)及联合评估对肛瘘活动性的诊断效能。结果PIA组瘘管FA值(0.178±0.018)、ADC值[(0.948±0.138)×10^(-3)mm^(2)/s]小于NIA组[(0.201±0.326)、(1.106±0.086)×10^(-3)mm^(2)/s],PIA组改良Van Assche评分(22.83±3.428)大于NIA组(17.95±3.374)。DTI、改良Van Assche评分及联合评估对肛瘘活动性均具备较高的诊断效能(AUC=0.826、0.798、0.851),其中联合评估诊断效能最优(P<0.05)。DeLong检验示联合评估AUC高于改良Van Assche评分,具有统计学差异(P<0.05),而联合评估与DTI、DTI与改良Van Assche评分的AUC比较无统计学差异(P>0.05)。结论DTI、改良Van Assche评分及联合评估均能有效诊断肛瘘活动性,联合评估能进一步提高肛瘘活动性的诊断效能,而DTI诊断效能与之相当。 展开更多
关键词 肛瘘 磁共振成像 van Assche评分 活动性 定量
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Optoelectronic Synapses Based on MXene/Violet Phosphorus van der Waals Heterojunctions for Visual‑Olfactory Crossmodal Perception 被引量:2
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作者 Hailong Ma Huajing Fang +3 位作者 Xinxing Xie Yanming Liu He Tian Yang Chai 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第6期38-52,共15页
The crossmodal interaction of different senses,which is an important basis for learning and memory in the human brain,is highly desired to be mimicked at the device level for developing neuromorphic crossmodal percept... The crossmodal interaction of different senses,which is an important basis for learning and memory in the human brain,is highly desired to be mimicked at the device level for developing neuromorphic crossmodal perception,but related researches are scarce.Here,we demonstrate an optoelectronic synapse for vision-olfactory crossmodal perception based on MXene/violet phosphorus(VP)van der Waals heterojunctions.Benefiting from the efficient separation and transport of photogenerated carriers facilitated by conductive MXene,the photoelectric responsivity of VP is dramatically enhanced by 7 orders of magnitude,reaching up to 7.7 A W^(−1).Excited by ultraviolet light,multiple synaptic functions,including excitatory postsynaptic currents,pairedpulse facilitation,short/long-term plasticity and“learning-experience”behavior,were demonstrated with a low power consumption.Furthermore,the proposed optoelectronic synapse exhibits distinct synaptic behaviors in different gas environments,enabling it to simulate the interaction of visual and olfactory information for crossmodal perception.This work demonstrates the great potential of VP in optoelectronics and provides a promising platform for applications such as virtual reality and neurorobotics. 展开更多
关键词 Violet phosphorus MXene van der Waals heterojunctions Optoelectronic synapses Crossmodal perception
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High-Quality van der Waals Epitaxial CsPbBr_(3)Film Grown on Monolayer Graphene Covered TiO_(2)for High-Performance Solar Cells 被引量:1
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作者 Zhaorui Wen Chao Liang +9 位作者 Shengwen Li Gang Wang Bingchen He Hao Gu Junpeng Xie Hui Pan Zhenhuang Su Xingyu Gao Guo Hong Shi Chen 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第4期239-246,共8页
Two-dimensional materials have been widely used to tune the growth and energy-level alignment of perovskites.However,their incomplete passivation and chaotic usage amounts are not conducive to the preparation of highq... Two-dimensional materials have been widely used to tune the growth and energy-level alignment of perovskites.However,their incomplete passivation and chaotic usage amounts are not conducive to the preparation of highquality perovskite films.Herein,we succeeded in obtaining higher-quality CsPbBr_(3)films by introducing large-area monolayer graphene as a stable physical overlay on top of TiO_(2)substrates.Benefiting from the inert and atomic smooth graphene surface,the CsPbBr_(3)film grown on top by the van der Waal epitaxy has higher crystallinity,improved(100)orientation,and an average domain size of up to 1.22μm.Meanwhile,a strong downward band bending is observed at the graphene/perovskite interface,improving the electron extraction to the electron transport layers(ETL).As a result,perovskite film grown on graphene has lower photoluminescence(PL)intensity,shorter carrier lifetime,and fewer defects.Finally,a photovoltaic device based on epitaxy CsPbBr_(3)film is fabricated,exhibiting power conversion efficiency(PCE)of up to 10.64%and stability over 2000 h in the air. 展开更多
关键词 all-inorganic perovskite solar cells buried interface modification monolayer graphene van der Waals epitaxial growth
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ZnSb/Ti_(3)C_(2)T_(x)MXene van der Waals heterojunction for flexible near-infrared photodetector arrays 被引量:3
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作者 Chuqiao Hu Ruiqing Chai +2 位作者 Zhongming Wei La Li Guozhen Shen 《Journal of Semiconductors》 EI CAS CSCD 2024年第5期99-105,共7页
Two-dimension(2D)van der Waals heterojunction holds essential promise in achieving high-performance flexible near-infrared(NIR)photodetector.Here,we report the successful fabrication of ZnSb/Ti_(3)C_(2)T_(x)MXene base... Two-dimension(2D)van der Waals heterojunction holds essential promise in achieving high-performance flexible near-infrared(NIR)photodetector.Here,we report the successful fabrication of ZnSb/Ti_(3)C_(2)T_(x)MXene based flexible NIR photodetector array via a facile photolithography technology.The single ZnSb/Ti_(3)C_(2)T_(x)photodetector exhibited a high light-to-dark current ratio of 4.98,fast response/recovery time(2.5/1.3 s)and excellent stability due to the tight connection between 2D ZnSb nanoplates and 2D Ti_(3)C_(2)T_(x)MXene nanoflakes,and the formed 2D van der Waals heterojunction.Thin polyethylene terephthalate(PET)substrate enables the ZnSb/Ti_(3)C_(2)T_(x)photodetector withstand bending such that stable photoelectrical properties with non-obvious change were maintained over 5000 bending cycles.Moreover,the ZnSb/Ti_(3)C_(2)T_(x)photodetectors were integrated into a 26×5 device array,realizing a NIR image sensing application. 展开更多
关键词 ZnSb nanoplates Ti_(3)C_(2)T_(x)MXene van der Waals heterojunction flexible photodetector image sensing
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COMPLEXES OF RARE EARTH NITRATE WITH SCHIFF BASE DERIVED FROM VANILLIN AND P-TOLUIDINE
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作者 Guo Fa LIU Bin LI Chong wu NA Kun Yuan MAO Institute of Material Science,Jilin University,Changchun,130023 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第2期119-120,共2页
In this paper,complexes of rare earth nitrate with Schiff base derived from vanillin(3-methoxy-4-hydroxy-benzaldehyde)and p-toluidine[LnL_2(NO_3)_2]NO_3(Ln=La-Eu except Pm,L=Schiff base ligand) have been prepared and ... In this paper,complexes of rare earth nitrate with Schiff base derived from vanillin(3-methoxy-4-hydroxy-benzaldehyde)and p-toluidine[LnL_2(NO_3)_2]NO_3(Ln=La-Eu except Pm,L=Schiff base ligand) have been prepared and characterized. 展开更多
关键词 COMPLEXES OF RARE EARTH NITRATE WITH SCHIFF BASE DERIVED FROM vanillin AND P-TOLUIDINE
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Mass-spring model for elastic wave propagation in multilayered van der Waals metamaterials 被引量:1
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作者 Yabin JING Lifeng WANG Yuqiang GAO 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第7期1107-1118,共12页
Multilayered van der Waals(vdW)materials have attracted increasing interest because of the manipulability of their superior optical,electrical,thermal,and mechanical properties.A mass-spring model(MSM)for elastic wave... Multilayered van der Waals(vdW)materials have attracted increasing interest because of the manipulability of their superior optical,electrical,thermal,and mechanical properties.A mass-spring model(MSM)for elastic wave propagation in multilayered vdW metamaterials is reported in this paper.Molecular dynamics(MD)simulations are adopted to simulate the propagation of elastic waves in multilayered vdW metamaterials.The results show that the graphene/MoS_(2)metamaterials have an elastic wave bandgap in the terahertz range.The MSM for the multilayered vdW metamaterials is proposed,and the numerical simulation results show that this model can well describe the dispersion and transmission characteristics of the multilayered vdW metamaterials.The MSM can predict elastic wave transmission characteristics in multilayered vdW metamaterials stacked with different two-dimensional(2D)materials.The results presented in this paper offer theoretical help for the vibration reduction of multilayered vdW semiconductors. 展开更多
关键词 multilayered van der Waals(vd W)metamaterial molecular dynamics(MD) mass-spring model(MSM) dispersion relation transmission characteristic
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