JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2013
·
IF 2.906
Jia Sun,Jin Yu,Pei-Cheng Zhang,Feng Tang,Yong-De Yue,Ya-Nan Yang,Zi-Ming Feng,Xue-Feng Guo
Caulis Bambusae in Taenia is a medicinal preparation from Bambusa tuldoides Munro consisting of skinless slices of the stem (bamboo shavings) and used as a traditional health food in tea, wine, and soup in Asia. Three novel lignans, (−)-7′-epi-lyoniresinol 4,9′-di-O-β-d-glucopyranoside (7), (−)-lyoniresinol 4,9′-di-O-β-d-glucopyranoside (8), bambulignan A (10), and seven known lignan compounds (1–6 and 9) were isolated from Caulis Bambusae in Taenia. The structures of the lignans were determined by detailed spectroscopic analysis (HRESIMS, HSQC, HMBC, NOE). All the isolated lignans were tested for antioxidant activities by DPPH and FARP assays. The results showed that the compounds (+)-lyoniresinol 9′-O-β-d-glucopyranoside (1) and (−)-7′-epi-lyoniresinol 9′-O-β-d- glucopyranoside (9) have strong free radical scavenging activity and reducing power.
研究领域:
药用植物学
·
天然产物化学
·
药物化学
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产品关联
DOI
PubMed
高影响因子
International Journal of Applied Ceramic Technology
·
2023
·Vol. 20
·期 3
·1740-1752
·
IF 2.1
Ling Pan,Pengju Chen,Peng Xiao,Ling He,Wei Zhou,Yang Li
The mullite and ytterbium disilicate (β-Yb 2 Si 2 O 7 ) powders as starting materials for the Yb 2 Si 2 O 7 /mullite/SiC tri-layer coating are synthesized by a sol–gel method. The effect of SiC whiskers on the anti-oxidation properties of Yb 2 Si 2 O 7 /mullite/SiC tri-layer coating for C/SiC composites in the air environment is deeply studied. Results show that the formation temperature and complete transition temperature of mullite were 800–1000 and 1300°C, respectively. Yb 2 SiO 5 , α-Yb 2 Si 2 O 7 , and β-Yb 2 Si 2 O 7 were gradually formed between 800 and 1000°C, and Yb 2 SiO 5 and α-Yb 2 Si 2 O 7 were completely transformed into β-Yb 2 Si 2 O 7 at a temperature above 1200°C. The weight loss of Yb 2 Si 2 O 7 /(SiC w –mullite)/SiC tri-layer coating coated specimens was 0.15 × 10 −3 g cm −2 after 200 h oxidation at 1400°C, which is lower than that of Yb 2 Si 2 O 7 /mullite/SiC tri-layer coating (2.84 × 10 −3 g cm −2 ). The SiC whiskers in mullite middle coating can not only alleviate the coefficient of thermal expansion difference between mullite middle coating and β-Yb 2 Si 2 O 7 outer coating, but also improve the self-healing performance of the mullite middle coating owing to the self-healing aluminosilicate glass phase formed by the reaction between SiO 2 (oxidation of SiC whiskers) and mullite particles.
研究领域:
材料科学
·
陶瓷学
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产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2013
·Vol. 24
·期 12
·4913-4918
·
IF 1.486
Wu Min,Lin Baoping,Cao Yi,Song Jiangang,Sun Ying,Yang Hong,Zhang Xueqin
In this paper, uniform and well dispersed silver-coated copper powders were prepared by replacing reaction at first. The structure and properties of the bimetallic powders were investigated by XRD, SEM and TGA. It was found that anti-oxidization of the silver-coated copper powders increased with the increase of the silver content slightly and a dense coating surface was observed at Ag content of 53.9 wt%. Furthermore, the pastes with relatively low silver content which were prepared from silver-coated copper powders, displayed high conductivity similar to pure silver even after sintering in air. And their sintering properties were also investigated at different temperature in air atmosphere. The film exhibits good electrical properties at sintering temperature between 800 and 900 °C. When the paste from silver-coated copper powder with Ag content of 53.9 wt% was printed on Al 2 O 3 substrate and sintered at 800 °C in air, the sheet resistance of the film is 0.036 Ω/□ only.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
Polymers
·
2024
·Vol. 16
·期 19
·2828
·
IF 4.7
Qidi Hu,Kai Zeng,Sheng Han,Jian Xu,Wenjing Hu,Jiusheng Li
Anti-wear and anti-oxidation abilities are two key properties of lubricants that play a crucial role in ensuring long-term stable equipment operation. In this study, we aimed to develop a base oil with good anti-oxidation and anti-wear properties for use under extreme pressure. The as-prepared metallocene polyalphaolefin (mPAO) was chemically modified using the trifluoromethanesulfonic acid (TfOH) catalysis through an alkylating reaction with triphenyl phosphorothioate (TPPT). During the experiments, when the reaction temperature exceeded 70 °C or the concentration of TfOH exceeded 2.67%, theβ-scission reaction in the alkylation process became significantly more pronounced. The physical and chemical properties of TPPT-modified mPAO (T-mPAO) were evaluated by nuclear magnetic resonance spectroscopy, Fourier trans-form infrared spectroscopy, gel–permeation chromatography, and ASTM standards. T-mPAO showed significantly improved antioxidant capacity, with the initial oxidation temperature increasing by 32 °C compared to the base oil, and it exhibited the slowest increase in acid number in the 96-h oven oxidation test. The tribological tests showed that T-mPAO had the lowest friction coefficient, wear track, and wear rate (72.7% lower than that of mPAO) as well as the highest PB(238 kg) and PD(250 kg) among all tested samples. Compared to mPAO, the average friction coefficient of TPPT-modified mPAO in the four-ball friction test was reduced by 30.5%, and by 16.4% in the TE77 reciprocating friction test. Based on the experimental results, T-mPAO had strong anti-oxidation ability and excellent lubricating performance.The successful synthesis of multifunctional mPAO has enabled lubricant base oil additization, making it possible to use it in more demanding work scenarios, greatly broadening its application scope and making lubricant formulation blending more flexible.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2024
·Vol. 35
·期 27
·1-12
·
IF 2.8
Zeng Shifan,Zhang Cong,Tian Haiming,Yao Guizhi,Shi Huan,Zhu Yong,Chi Shangpeng,Kan Xucai,Liu Xiansong
The magnetic powder Sm 2 Fe 17 N x has recently garnered considerable interest due to its competitive pricing. In this study, the preparation of Sm 2 Fe 17 N x magnetic powder by melt quenching and nitriding process was successfully completed. In order to obtain a higher coercivity, the particle size of the magnetic powder was reduced to a diameter of less than 2 μm through ball milling. It was observed that as the ball milling time was extended, the coercivity of the magnetic powder exhibited a decline that was premature in comparison to the expected results. Additionally, the presence of minute particles of magnetic powder may appear spontaneous combustion phenomenon. Accordingly, Sm 2 Fe 17 N x magnetic powder with high coercivity ( H cj = 842.8 kA/m) was prepared by phosphoric acid passivation process. Through XRD patterns, it was found that the phosphoric acid passivation process markedly enhanced the antioxidant capacity of the magnetic powder. Through SEM images, it is found that the fine magnetic powder exhibits a sheet structure and has strong shape anisotropy. The research indicate that the phosphoric acid passivation process is effective in enhancing the stability of Sm 2 Fe 17 N x magnetic powder and inhibiting the oxidation reaction of magnetic powder during use. This has a beneficial impact on the service life of permanent magnet devices in industrial production.
研究领域:
材料科学
·
磁学
✓ 已验证
产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2024
·
IF 8.5
Mantong Zhao,Zhongyuan Liu,Ying Sun,Haohao Shi,Yonghuan Yun,Meihui Zhao,Guanghua Xia,Xuanri Shen
Hydrocolloids synthesized by gallic acid (GA) and ferulic acid (FA) grafting onto chitosan (CS) were characterized, and their effects on PhIP formation in pan-fried golden pompano were investigated. Spectrograms including nuclear magnetic resonance, Fourier transform infrared spectroscopy and ultraviolet-visible confirmed that GA and FA were successfully grafted onto CS via covalent bonds, with grafting degree of 97.06 ± 2.56 mg GA/g and 93.56 ± 2.76 mg FA/g, respectively. The CS-g-GA and CS-g-FA exerted better solubility and antioxidant activities than CS. For the 8-min pan-fried golden pompano fillets, CS-g-GA and CS-g-FA (0.5%, m/v) significantly reduced the PhIP formation by 61.71% and 81.64%, respectively. Chemical models revealed that CS-g-GA and CS-g-FA inhibited PhIP formation mainly by decreasing the phenylacetaldehyde contents from Maillard reaction and competing with creatinine to react with phenylacetaldehyde. Therefore, it was suggested that CS-g-phenolic acids emerge as novel coating for aquatic products during processing and inhibit heterocyclic amines generation.
研究领域:
食品科学
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
EUROPEAN FOOD RESEARCH AND TECHNOLOGY
·
2015
·Vol. 242
·期 4
·537-546
·
IF 1.559
Yang Hongli,Huang Zhongping,Chen Yin,Zhang Changjun,Ye Mengdie,Wang Lili
Propolis, a well-known folk medicine in the world, has drawn growing attention due to the various bioactivities. An on-line method of coupling HPLC with 2,2′-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) cationic radical scavenging detection (HPLC–ABTS) was developed to screen the single polyphenol possessing ABTS cationic radical scavenging activity in ethanol extracts of Chinese propolis (EECP). Ten common polyphenols were selected from the active fingerprints of ten EECP samples obtained from different provinces of China by the on-line HPLC–ABTS method and quantified by Trolox equivalent. Their contributions to the antioxidant property of EECP were compared. Furthermore, Pearson’s correlation analysis was applied to determine whether there was a correlation between the antioxidant activity of individual polyphenol and total antioxidant activity of EECP. The results indicated that the composition of polyphenols in ten EECP samples obtained from China was similar. But the different polyphenols contributed in different way. Caffeic acid, kaempferol, and galangin simultaneously were the most prominent contributors to the antioxidant properties of ten EECP. The contributions of pinobanksin 3-acetate, caffeic acid phenethyl ester (CAPE), and caffeic acid cinnamyl ester varied largely with the different geographical regions. They, except galangin, significantly correlated with the antioxidant property of propolis. However, pinobanksin, pinocembrin, chrysin, p -coumaric acid, and ferulic acid rarely contributed to the antioxidant property of Chinese propolis. Therefore, the on-line HPLC–ABTS method was convenient, effective, and comprehensive to evaluate the contributions of polyphenols to the antioxidant property for Chinese propolis.
研究领域:
植物化学
·
药理学
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产品关联
DOI
高影响因子
Materials
·
2018
·Vol. 11
·期 3
·350
·
IF 2.467
Guangyuan Yang,Zhixiong Huang,Xu Wang,Bo Wang
The paper proposed a method to improve the anti-oxidation performance of carbon fibers (CF) at high temperature environment by coating silicon dioxide (SiO2) and silicon carbide (SiC). The modified sol-gel method had been used to ensure the proper interface between fibers and coating. We used polydimethylsiloxane and ethyl orthosilicate to make stable emulsion to uniformly disperse SiC nanoparticles. The modified SiO2/SiC coating had been coated on CF successfully. Compared with the untreated CF, the coated fibers started to be oxidized around 900 °C and the residual weight was 57% at 1400 °C. The oxidation mechanism had been discussed. The structure of SiC/SiO2coated CF had been characterized by scanning electron microscope and X-ray diffraction analysis. Thermal gravimetric analysis was used to test the anti-oxidation ability of CF with different coatings.Keywords:carbon fiber;oxidation resistance;coating;characterization
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Polymers
·
2019
·Vol. 11
·期 6
·970
·
IF 3.164
Wen Zhang,Zhi-Yi Yang,Xian-Wei Cheng,Ren-Cheng Tang,Yi-Fan Qiao
Natural bioactive compounds have received increasing attention in the functional modification of textiles. In this work, tannic acid was used to impart antibacterial and antioxidant functions to silk using an adsorption technique, and the adsorption properties of tannic acid on silk were studied. The adsorption quantity of tannic acid on silk increased with decreasing pH in the range of 3–7. The rates of the uptake of tannic acid by silk were well correlated to the pseudo-second-order kinetic model, and the calculated activation energy of adsorption was 93.49 kJ/mol. The equilibrium adsorption isotherms followed the Langmuir model. The adsorption rate and isotherm studies demonstrated that the chemical adsorption of tannic acid on silk occurred through the ion-ion interaction between tannic acid and silk. Tannic acid displayed good building-up properties on silk. The silk fabric treated with 0.5% tannic acid (relative to fabric weight) exhibited excellent and durable antibacterial properties. Moreover, the silk fabrics treated with 2% and 5% tannic acid had good and durable antioxidant properties. The treatment by tannic acid had less impact on the whiteness of the silk fabric. In summary, tannic acid can be used as a functional agent for preparing healthy and hygienic silk materials.
研究领域:
纺织科学
·
生物化学
✓ 已验证
DOI
高影响因子
Food Bioscience
·
2025
·
IF 5.9
Wenyuchu Chen,Fang Tian,Yongjing Xu,Yujin Li,Weiliang Guan,Chenyang Lu,Sheng Hu,Luyun Cai
Fish oils (FOs) are rich in omega-3 polyunsaturated fatty acids, which provide several health benefits. However, their oral bioavailability and stability are often limited due to the oxidation of polyunsaturated fatty acids, which degrade the oil's nutritional and sensory properties over time. In this study, FO microcapsules were prepared using pea protein isolate (PPI), β-cyclodextrin (β-CD), and carbon quantum dots (CQDs) as wall materials through a freeze-drying method. The results demonstrated that the use of PPI/β-CD/CQDs composite significantly improved the encapsulation efficiency, stability, and antioxidant properties of the microcapsules, suggesting a promising approach for enhancing the shelf-life and health benefits of fish oil. Additionally, the peroxide value (POV) and thiobarbituric acid (TBA) values of the microcapsules increased with temperature and storage time. Notably, the incorporation of CQDs markedly improved the antioxidant properties of the microcapsules, thereby extending their storage stability. In vitro gastrointestinal digestion simulations demonstrated that microencapsulation facilitated the absorption of beneficial substances in fish oil within the human gut. This study offers valuable insights into the development of more efficient fish oil microcapsules for potential applications in food and pharmaceutical applications.
研究领域:
食品科学
·
营养学
✓ 已验证
产品关联
DOI
高影响因子
Materials Science and Engineering B-Advanced Functional Solid-State Materials
·
2024
·
IF 3.9
Hongli Liu,Weiqiang Xie,Qi Zhao,Ying Sui,Zhongxian Liu,Tiangang Zhang,Zhiqiang Zhang,Shuang Sun,Jianwei Jia
SiC fibers have excellent properties such as high-temperature resistance, oxidation resistance, and high strength, and it is an ideal material for high-temperature structures. However, with the continuous development of technology, the application conditions of the material are becoming more and more stringent. Therefore, the properties of SiC fibers need to be further improved to adapt to the ultra-high temperature environment. In this work, yttrium was introduced into the precursor solution using the precursor transformation method, and yttrium-containing SiC fibers were prepared by electrospinning. The microstructure, chemical composition, oxidation resistance, and mechanical properties of the specimens were tested. The results showed that the samples have good thermal stability after ceramization at 1400 °C, and the Y 2 SiO 5 produced in the fiber matrix further improves the antioxidant properties of the fibers. Additionally, the yttrium-containing SiC fibers maintained excellent flexibility, and the high-temperature resistance of SiC fibers was significantly enhanced.
研究领域:
材料科学
·
高温结构材料
✓ 已验证
DOI
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2025
·
IF 6.6
Limin Wang,Qianfei Jia,Yuan Li,Hui Zhao,Zijian Wu
This study investigated the chitosan (CS)-octenyl succinic anhydride (OSA) starch complex as a stabilizer for Pickering emulsions. The effects of OSA concentration (0.5wt%-2.5wt%) and viscosity (OSA1, OSA2, OSA3) on the stability and physiochemical properties of emulsion were examined. The results showed that CS-OSA with 2.0wt% concentration OSA stabilized emulsion exhibited optimal emulsifying capacity. Contact angle analysis, Fourier transform infrared spectrometer (FTIR) and X-difference diffractometer (XRD) were utilized to explore the stabilized mechanism of CS-OSA on emulsion, results confirmed the CS and OSA interactions, and strong adsorption of CS-OSA particles at the oil-water interface. Furthermore, CS-OSA stabilized emulsion loading curcumin were assessed, results showed that curcumin loaded emulsion exhibited high stability and better antioxidant capacity than free CS during 10-day storage. The overall study offers valuable insights into the utilization of CS-OSA emulsifiers in delivery application for lipophilic bioactive molecules.
研究领域:
食品科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）