Foods
·
2021
·Vol. 10
·期 2
·239
·
IF 4.35
Nina Bao,Di Wang,Xizhe Fu,Hujun Xie,Guizhen Gao,Zisheng Luo
LotusReceptaculum Nelumbinishas been sparking wide research interests due to its rich phenolic compounds. In the present work, ultrasonic-assisted extraction coupled with glycerol was employed to extract phenolic compounds fromReceptaculum Nelumbinisand the process was optimized using a response surface methodology with Box-Behnken design (BBD). The optimal conditions for the total phenolic content (TPC) extract were obtained: glycerol concentration of 40%, an extraction temperature of 66 °C, ultrasonic time of 44 min, and the solvent-to-solid ratio of 55 mL/g. Under these optimum extraction conditions, the extraction yield of TPC was 92.84 ± 2.13 mg gallic acid equivalents (GAE) /g. Besides, the antioxidant activities demonstrated the ability of free radical scavenging by four different methods that included 2,2-Diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and reducing activity (RA) were 459.73 ± 7.07, 529.97 ± 7.30, 907.61 ± 20.28, and 983.66 ± 11.80 μmol TE/g, respectively. Six phenolic compounds were identified by ultra-high pressure liquid chromatography combined with triple-time-of-flight mass spectrophotometry (UPLC-Triple-TOF/MS) from the extracts. Meanwhile, Fourier transform infrared (FTIR) was conducted to identify the characteristic functional groups of the extracts and thus reflected the presence of polyphenols and flavonoids. Scanning electron microscopy (SEM) illustrated the microstructure difference of four treatments, which might explain the relationships between antioxidant activities and the structures of phenolic compounds.
研究领域:
植物化学
·
分析化学
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食品科学
·
天然产物研究
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DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Zeshuai Li,Feifei Zhou,Baosheng Xu,Donghui Guo
We present a simple way to fabricate high-entropy (La 0.2 Nd 0.2 Sm 0.2 Dy 0.2 Yb 0.2 ) 2 Zr 2 O 7 (HE-RE 2 Zr 2 O 7 ) ceramic nanofibers using the electrospinning and annealing processing in this work. The microstructure of nanofibers was characterized by thermal gravity-differential scanning calorimetry (TG-DSC), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM), respectively. Meanwhile, the diameter and grain growth of HE-RE 2 Zr 2 O 7 nanofibers under 1000 °C was analyzed. Results indicate that HE-RE 2 Zr 2 O 7 nanofibers can be prepared at temperatures above 400 °C and the crystallite size can be controlled by annealing temperature. Both diameter and the grain growth of HE-RE 2 Zr 2 O 7 nanofibers are lower than that of La 2 Zr 2 O 7 nanofibers, attributed to the sluggish diffusion effect. The advantages of HE-RE 2 Zr 2 O 7 nanofibers can further enlarge the application of nanofibers in the aspect of high-temperature thermal insulation materials.
研究领域:
材料科学
·
陶瓷
·
纳米技术
·
隔热材料
✓ 已验证
DOI
高影响因子
ELECTROANALYSIS
·
2020
·Vol. 32
·期 8
·1772-1779
·
IF 2.544
Yifei Yang,Yue Sun,Mingzhu Jin,Ru Bai,Yutong Liu,Yingqi Wu,Wei Wang,Xuewei Feng,Siyu Li
Superoxide dismutase (SOD) plays an important role in nearly all living cells. In this study, SOD imprinted poly(ionic liquid)s (SIPILs) were prepared on the surface of the bare Au electrode modified with nano-palladium and nano-gold (Au/nPd/nAu/SIPILs). SIPILs was synthesized with 1-vinyl-3-propyl imidazole sulfonate ionic liquids as functional monomers via electrochemically mediated atom transfer radical polymerization (eATRP) catalyzed by SOD. The Au/nPd/nAu/SIPILs was examined by cyclic voltammetry (CV), scanning electron microscope (SEM), energy-dispersive spectrometer (EDS) and X-ray photoelectron spectroscopy (XPS). The Au/nPd/nAu/SIPILs was also used as an electrochemical sensor to determine SOD by differential pulse voltammetry (DPV). Under the optimal conditions, the detection range of SOD was from 1.0×10 −8 to 1.0×10 2 mg L −1 with a limit of detection of 8.90×10 −9 mg L −1 (S/N=3). Compared with other methods, the sensor based on SIPILs had the broader linear range and lower detection limit.
研究领域:
分析化学
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材料科学
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电化学
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生物传感器
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产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2016
·Vol. 27
·期 9
·9278-9285
·
IF 1.798
Liu Ziyu,Xu Guangliang,Zhang Ming,Xiong Kun,Meng Pingyuan
Cobalt ferrite/reduced graphene oxide (CoFe 2 O 4 /RGO) nanocomposites were initially prepared by the interaction of alkyne-functionalized CoFe 2 O 4 NPs and azide-functionalized graphene oxide (GO–N 3 ) via the Cu (I)-catalyzed click reaction. The morphology and structure of CoFe 2 O 4 /RGO were investigated by means of XRD, FTIR, TGA, TEM, SEM and the electromagnetic parameters were measured by vector network analyzer. For CoFe 2 O 4 /RGO composites with click reaction, the minimum reflection loss could reach −40 dB at 6.8 GHz with a matching thickness of 4.0 mm, and also it had a bandwidth below −10 dB ranging from 5.8 to 8.5 GHz. The CoFe 2 O 4 /RGO composites with click reaction exhibited better microwave absorbing performance than the physical mixture. Furthermore, the covalent ligation between CoFe 2 O 4 NPs and graphene oxide could make the composites have a promising future in electromagnetic wave absorption materials.
研究领域:
材料科学
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纳米技术
·
电磁材料
·
化学
✓ 已验证
产品关联
DOI
高影响因子
Surfaces and Interfaces
·
2024
·
IF 5.7
Jin Cheng,Lili Xing,Aijing Li,Xinpeng Chen,Jialuo Chen,Shenzhou Lu,Ning Qi,Guoqiang Chen,Tieling Xing
As a good substrate, silk fibers are widely employed in the field of intelligent textiles. In this work, the surface of silk fibers were firstly roughened by formic acid and sensitized by tannic acid, and then the silver ammonia solution was reduced by glucose to synthesize nano-silver in situ on the silk surface to obtain composite conductive silk fibers with resistivity as low as 0.24 mΩ·cm. It was proved by scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) tests that a uniformly deposited nano-silver layer was fabricated on the silk surface. The prepared silk fibers had stable mechanical, thermal, electrical, and antibacterial properties and can be used for human sensing.
研究领域:
纺织工程
·
材料科学
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2021
·Vol. 14
·期 21
·6716
·
IF 3.623
Shiyu Ma,Yan Lu,Bo Wang,Jinkai Li
White LEDs were encapsulated using Cs4PbBr6quantum dots and Gd2O3:Eu red phosphor as lamp powder. Under the excitation of a GaN chip, the color coordinates of the W-LED were (0.33, 0.34), and the color temperature was 5752 K, which is close to the color coordinate and color temperature range of standard sunlight. The electric current stability was excellent with an increase in the electric current, voltage, and luminescence intensity of the quantum dots and phosphors by more than 10 times. However, the stability of the quantum dots was slightly insufficient over long working periods. The photocatalytic devices were constructed using TiO2, CsPbBr3, and NiO as an electron transport layer, light absorption layer, and catalyst, respectively. The Cs–Pb–Br-based perovskite quantum dot photocatalytic devices were constructed using a two-step spin coating method, one-step spin coating method, and full PLD technology. In order to improve the water stability of the device, a hydrophobic carbon paste and carbon film were selected as the hole transport layer. The TiO2layer and perovskite layer with different thicknesses and film forming qualities were obtained by changing the spin coating speed. The influence of the spin coating speed on the device’s performance was explored through SEM and a J–V curve to find the best spin coating process. The device constructed by the two-step spin coating method had a higher current density but no obvious increase in the current density under light, while the other two methods could obtain a more obvious light response, but the current density was very low.
研究领域:
材料科学
·
光电
·
光催化
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DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2021
·
IF 3.498
Xiaoqing Xie,Yanfei Wang,Weini Zhou,Can Chen,Zeng Xiong
A new synthetic method was designed to prepare poly (trimesoyl chloride-co-polyethyleneimine) (PEI-TMC). Characterization of PEI-TMC was investigated by FTIR, SEM, EDS , XPS, TGA , and BET. TGA test revealed that the PEI-TMC had excellent thermal stability. The BET specific surface area (4.74 m 2 g −1 ) and pore diameter of about 9.44 nm indicated that PEI-TMC possessed a mesoporous structure. The adsorption behavior of U(VI) on the PEI-TMC was investigated. The thermodynamic analysis showed that the process of PEI-TMC adsorption of U(VI) was endothermic and spontaneous, and the adsorption efficiency was better at higher temperatures. The U(VI) sorption on PEI-TMC was conformed to the Langmuir adsorption isotherm and pseudo-second-order kinetic models . The adsorption mechanism of U(VI) with PEI-TMC was systematically elucidated by XPS and FTIR. Under the best condition, the maximum adsorption capacity of PEI-TMC could reach 212.8 mg g −1 by calculating the Langmuir isothermal model. It indicated that PEI-TMC was a potential adsorbent for the treatment of U(VI)-containing wastewater.
研究领域:
环境科学
·
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2019
·
IF 5.155
Azhar Ali Haidry,Lijuan Xie,Zhe Wang,Zhong Li
Employing TiO 2 as a gas sensing material is advantageous owing to its excellent hydrogen surface receptiveness and stability under extreme conditions. However, their commercial applications are constrained by limited operating temperature range (150–400 °C) and poor selectivity. In this work, we demonstrate that the ordered mesoporous structured TiO 2 is highly favourable for room temperature hydrogen sensing. The sensors prepared with evaporation induced self-assembly (EISA) showed best response ~2.98 × 10 2 toward 1000 ppm H 2 at room temperature with a sensitivity of ~4.6 ± 1.5 × 10 6 ohm/ppm. Moreover, the sensor showed a response time of ~85 s (recovery time of ~198 s) with full baseline recovery and a selectivity factor of ~290 to 1000 ppm of interfering reducing gases CO and CH 4 at room temperature. With a power consumption of ~1 × 10 −9 W the sensors are incredibly suitable for practical applications. We performed XRD, SEM, TEM, XPS, BET and PL characterization not only to confirm the crystal structure, morphology at nanoscale, surface chemical identification, specific surface area, pore size and photo-generated charge species that contribute to the electronic transport properties but sensing mechanism also.
研究领域:
材料科学
·
化学工程
·
纳米技术
·
气体传感
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产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2017
·Vol. 5
·期 13
·3264-3275
·
IF 5.256
Bei Zhao,Dingyi Shen,Jun Yang,Shanshan Hu,Xianju Zhou,Jianfeng Tang
Sr2ScF7:Ln3+ (Ln = Ce, Tb, Eu, Sm, Dy, Er, Tm, Ho and Yb) nanocrystals were firstly synthesized via a one-step hydrothermal route without employing any surfactants. The shape and size of the Sr2ScF7 nanocrystals could be readily tuned from nanorods with 120 nm length and 50 nm width to nanoparticles with a uniform diameter of 15 nm by doping 30% Ln3+ with a larger ionic radius. Furthermore, the influence of pH values, F− sources and different surfactants on the sizes and morphologies (including nanorods, quadrangular microplates, cubes and polyhedrons) of the as-prepared products was systematically investigated and the possible formation mechanism for the products has been proposed. The XRD, SEM, EDS, PL analysis and decay lifetimes were used to characterize the products. For DC photoluminescence, the Sr2ScF7:Ln3+ nanocrystals show the characteristic f–f transitions with emission colors of bluish violet (Ce3+, Tm3+), green (Tb3+, Er3+, Ho3+), blue (Dy3+) and orange (Eu3+, Sm3+) respectively. Under single wavelength 980 nm excitation, the blue UC emissions of Sr2ScF7:Yb3+,Tm3+ nanocrystals at 474 nm due to the 1G4 → 3H6 transition of Tm3+, the green UC emissions of Sr2ScF7:Er3+ nanocrystals at 522/544 nm assigned to the 2H11/2 → 4I15/2/4S3/2 → 4I15/2 transitions and the red UC emissions of Sr2ScF7:Yb3+,Er3+ at 660 nm from 4F9/2 → 4I15/2 transition of Er3+ were observed. Based on the generation of red, green, and blue emissions, the Sr2ScF7:Yb3+,Er3+,Tm3+ nanocrystals could produce multicolor, particularly in the white region (0.320, 0.330) by controlling the doping concentration of Tm3+ in the Sr2ScF7:Yb3+,Er3+,Tm3+ nanocrystals. Controlling the doping concentration of Tm3+ is an effective way of modulating the luminescence properties of Sr2ScF7:Ln3+ by controlling its size and morphology. The as-synthesized phosphors might be potentially applied in the fields of color displays, light, photonics and biological imaging.
研究领域:
材料科学
·
纳米技术
·
光学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2024
·
IF 5.3
Xier Gong,Jie Wang,Liying Bin,Weirui Chen,Ping Li,Pengran Guo,Zhiliang Chen,Bing Tang
The present study aimed to prepare an aluminum-based nanoflower (Al-NF) adsorbent using wasted aluminum polishing solution as raw materials, which effectively isolated the residues of anti-epidemic related drugs (lopinavir (LPV) and ciprofloxacin (CIP)) from wastewater. A comprehensive characterization approach involving SEM, XRD, BET, TGA, FTIR, and XPS was employed to investigate the adsorption capacity and mechanism of Al-NF towards LPV and CIP. The results revealed that the adsorption process involved both homogeneous and non-homogeneous interactions between the LPV/CIP molecules and the Al-NF surface. According to the Langmuir model calculations, the maximum adsorption capacities of Al-NF for LPV and CIP at 293.15 K were determined to be 32.41 mg/g and 14.43 mg/g, respectively, while their adsorption kinetics followed a pseudo-second-order model more appropriately. Furthermore, the spontaneous exothermic nature of LPV/CIP adsorption on Al-NF was confirmed by thermodynamic analysis. The mechanism investigations indicated that hydrogen bonding, electrostatic interaction, π-π bonding interaction, as well as n-π EDA bonding collectively contributed to the overall adsorption process on the Al-NF surface for both LPV and CIP species. Additionally, the reusability demonstrated by Al-NF highlights its potential as a promising low-cost material for removing anti-epidemic related drug residues from wastewater utilizing industrial hazardous wastes.
研究领域:
环境科学
·
材料科学
·
化学工程
·
废水处理
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产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2022
·Vol. 29
·期 19
·27677-27687
·
IF 5.19
Long Yujiao,Li Hongna,Jin Hongmei,Ni Jinren
The chemical and biological mechanisms of electrochemical elimination of Microcystis aeruginosa ( M. aeruginosa ) using boron-doped diamond (BDD) anode were comparatively explored in three different electrolytes (chloride, sulfate, and phosphate solutions). The most efficient elimination of M. aeruginosa was observed in chloride solution, which was attributed to the greatest total long-lived oxidants from the favorable formation of active chlorine. Moreover, the high permeability of active chlorine resulted in profound intracellular damages to chlorophyll- a , microcystin-LR (MC-LR), superoxide dismutase (SOD) enzyme, and DNA in the chloride system. The change of membrane permeability and degradation of the released MC-LR induced by active chlorine were further confirmed by the increase of extracellular MC-LR in the initial 5 min and a complete decay in the subsequent 15 min, while the change in morphology of algae cells was insignificant from SEM images. In sulfate and phosphate electrolytes, membrane damages were much more pronounced based on lipid peroxidation observation, although changes in cell morphology was found more significant in phosphate system. The higher concentrations of oxidants (·OH, O 3 , H 2 O 2 , S 2 O 8 2− ) generated in sulfate than in phosphate solution explained the greater efficiency of electrochemical elimination of M. aeruginosa in the sulfate electrolyte in terms of changes of cell density, OD 680 , chlorophyll- a , MC-LR, lipids, SOD enzyme, and DNA.
研究领域:
环境科学
·
电化学
·
水生生物学
·
毒理学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF DENTISTRY
·
2020
·
IF 3.242
Jinzhao Yu,Xiaoyu Huang,Xuedong Zhou,Qi Han,Wen Zhou,Jingou Liang,Hockin H.K. Xu,Biao Ren,Xian Peng,Michael D. Weir,Mingyun Li,Lei Cheng
Objectives Resin infiltrant is used in early enamel caries. However, commercial resin infiltrant lacks persistent antibacterial activity. Dimethylaminododecyl methacrylate (DMADDM) was added to resin infiltrant to give it sustainable antibacterial properties and inhibit demineralization. Methods After the application of resin infiltrant to bovine enamel, cytotoxicity, surface roughness, and aesthetics were assessed. A multi-species biofilm was incubated on the enamel disk before and one month after microbial-aging. After a 48-h anaerobic incubation, biomass accumulation, metabolic activity, and lactic acid were analyzed using a crystal violet assay, an MTT (3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, and a lactic acid assay. Biofilm structure and composition were determined by live/dead staining, exopolysaccharide (EPS) staining, scanning electron microscopy (SEM), and quantitative polymerase chain reaction (qPCR). The depth and content of demineralization were tested by transverse microradiography (TMR). Results Incorporating DMADDM did not increase the cytotoxicity or change the physical properties when the mass fraction of the DMADDM was 2.5–10 %. The modification decreased the amount of bacterial biofilm, metabolic activity, lactic acid production, EPS, and the proportion of Streptococcus mutans in the biofilms. It also provided anti-demineralization effects. The surface roughness and antibacterial ability were not changed after one month of microbial-aging. Conclusion The incorporation of DMADDM improved the antibacterial and anti-demineralization effects of the material. It demonstrated a sustained antibacterial effect. Clinical significance The antibacterial modification might be a potential choice for future clinical applications to inhibit early enamel caries.
研究领域:
牙科材料
·
口腔微生物学
·
龋齿预防
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）