MOLECULES
·
2018
·Vol. 23
·期 2
·359
·
IF 3.098
Qing Li,Shihua Yang,Yongqiang Li,Xiaofeng Xue,Yonghua Huang,Hengguo Luo,Yiming Zhang,Zhichao Lu
Mistletoes are used medicinally in order to treat various human illnesses. Few studies have reported on the phenolic content and antioxidant properties of Chinese mistletoes (CMs). In this work, the total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activities of soluble and insoluble-bound phenolic extracts from CMs hosted byCamellia assamica(Mast.) Chang (CMC) andPyrus,i,f.(CMP) were compared. Phenolic compounds in CMC and CMP were identified and quantified using high-performance liquid chromatography (HPLC). The results indicated that the TPC of soluble phenolic extracts was higher than insoluble-bound phenolic counterparts in both CMC and CMP. In addition, the TPC of soluble, insoluble-bound and total phenolic fractions (9.91 ± 0.23, 4.59 ± 0.27 and 14.50 ± 0.35 μmol ferulic acid equivalents per gram (FAE/g) dry sample) extracted from CMP were higher than those extracted from CMC. The soluble phenolic extracts in CMP showed higher antioxidant activities than those in CMC. Eighteen phenolic compounds from soluble and insoluble-bound phenolic extracts from the CMs were identified and quantified by HPLC. This study indicates that CMC and CMP, especially the latter, could be sources of antioxidants in human health care.Keywords:Chinese mistletoes;phenolics;phenolic contents;antioxidant activity
研究领域:
植物化学
·
药理学
✓ 已验证
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2015
·
IF 4.321
Fei Wang,Jing Ren,Yunliang Cai,Long Sun,Chuanling Chen,Shuai Liang,Xingmao Jiang
High dispersed palladium nanoparticles with the size of about 3.8 nm confined within ZSM-5 zeolite catalyst (Pd/ZSM-5-IS) was successfully synthesized by in situ synthesis method based on azeotropic distillation assisted fabrication. Liquid phase selective hydrogenation of p -nitrophenol (PNP) to p -aminophenol (PAP) was chosen as model reactions to evaluate the catalytic behavior of the Pd/ZSM-5 catalysts. Thiophene and 4,6-dimethyldibenzothiophene were used as poisons to test their anti-poisoning ability. Pd/ZSM-5-IS catalyst exhibited higher catalytic activity in hydrogenation of PNP to PAP than sample prepared by impregnation method (Pd/ZSM-5-IM), which was mainly attributed to entering of Pd nanoparticles into the intracrystalline mesovoids of the ZSM-5 support for in situ method efficiently prevent active sites from loss and aggregation. In addition, Pd/ZSM-5-IS catalyst not only maintained high activity for five consecutive runs, but also showed high sulfur tolerance for the hydrogenation reactions. This simple and versatile method also can be extended to cover many kinds of other supported catalysts for broad applications in many other catalytic reactions in the future.
研究领域:
催化化学
·
材料科学
✓ 已验证
DOI
高影响因子
Desalination and Water Treatment
·
2024
·
IF 1
Lijun Luo,Wei Tan,Huabin Xong,Colin J. Barrow,Pei He,Wenrong Yang,Hongbin Wang
ABSTRACT A novel phenyl-functionalized mesoporous silica based on TiO 2 supporter was synthesized to remove bisphenol A (BPA) quickly, which is a representative endocrine disrupting chemical. The prepared sorbents were characterized by nitrogen (N 2 ) adsorption-desorption measurement (BET) and Fourier transform infrared spectroscopy. The effects of the temperature, initial pH value and initial BPA concentration of solution on the adsorption capacity were investigated. And adsorption behaviors of the adsorbent for BPA, such as adsorption kinetics, isotherms, thermodynamics and effect of coexisting pollutants, were also investigated. The result indicated the maximum adsorption capacity of TiO 2 - Mip-Ms (22 mg g –1 ) is the two times higher than that of TiO 2 -Nip-Ms (11 mg g –1 ), and the Langmuir model fits better than Freundlich model. The adsorption kinetic of BPA onto TiO 2 -Mip-Ms and TiO 2 - Nip-Ms belonged to the pseudo-second-order kinetic model, and adsorption rate constant of TiO 2 - Mip-Ms (0.0156 g mg –1 min –1 ) is near three times than that of TiO 2 -Nip-Ms (0.0058 g mg –1 min –1 ). The BPA adsorption onto TiO 2 -Mip-Ms was thermodynamically feasible and spontaneous.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2021
·
IF 8.742
Caidi Chen,Hengxin Xie,Yuyao Jiang,Yawen Chen,Yiran Liang,Gulihumaer Ruzetuoheti,Shijun Liao,Xiuhua Li,Biaowen Wei
In this work, AEMs based on poly(arylene ether sulfone)s skeletons were tailored with three kinds of hydrophobic components: biphenol (BP) with conjugate double benzene rings , bisphenol A (BPA) containing isolated double benzene rings and fluorene-9-bisphenol (FBP) with Cardo ring skeleton of four benzene rings. A series of quaternized poly(arylene ether sulfone)s (QPAES) membranes were fabricated successfully including QPAES-BP, QPAES-BPA and QPAES-FBP. The obtained membranes were applied in diffusion dialysis (DD) process of simulated waste acid (1.0 mol L -1 HCl and 0.2 mol L -1 FeCl 2 ) to figure out the influence of hydrophobic structures on DD performance. The dialysis coefficients ( U H + ) were in the range from 12.13 × 10 -3 m h -1 to 13.28 × 10 -3 m h -1 , while the separation factors (S) were in the range from 67.33 to 126.37. The resultant membranes show much better performance compared with the commercial TWDDA1 membrane ( U H + = 8.5 × 10 -3 m h -1 , S = 18.5). Interestingly, the membrane structures and properties revealed that the rigid aromatic component induced low water swelling, strong mechanical property and microphase separation , the nature of the structure offers high U H + as well as high S. The results show that the fabricated membranes are potential candidates for the acid recovery in diffusion dialysis, especially the QPAES-BP membrane tuned with rigid linear conjugated hydrophobic component.
研究领域:
高分子科学
·
膜技术
·
分离科学
·
材料工程
·
化学工程
✓ 已验证
DOI
高影响因子
LANGMUIR
·
2022
·
IF 4.331
Yuqing Ye,Yuan Li,Jie Wang,Shuai Yuan,Xiaojun Xu,Xinning Zhang,Junwen Zhou,Bo Wang,Xiaojie Ma
Environmentally persistent free radicals (EPFRs) have been recognized as one of the important emerging contaminants with biological toxicity, environmental persistence, and global mobility. Previous studies have identified the catalytic role of surface metal oxides in EPFRs formation and illustrated the metal-dependence of EPFRs by studying on various metal oxide nanoparticles and single crystals. However, there is still lack of an understanding on the formation of EPFRs from the point of view of metal sites. Various factors (e.g., crystalline phases and surface species) of metal oxides are regarded to contribute to the generation of EPFRs, which present profound difficulties for scientists to tease apart the impact of metal type. Herein, a laboratory investigation, in terms of the acidity and oxidation strength of metal cations, was conducted by selecting metal-variable isostructural metal–organic frameworks as material platforms. Specifically, we evaluated EPFRs generation on MIL-100(M) (M = Al, Cr, Fe) from chlorine-substituted phenol vapor and catechol under thermal conditions. It is found that high Lewis acidity of metal sites is crucial for capturing the above two phenolic precursors, activating the O–H bond and promoting EPFRs formation. Radical species with half-life as long as 70 days were generated on MIL-100 rich in 5-fold coordinated Al3+ sites. The unpaired electron spin density donation was further confirmed by using 27Al solid-state nuclear magnetic resonance spectroscopy. Despite their higher oxidation power than Al3+, the exposed Cr3+ and Fe3+ sites show undetectable catalytic activity for the formation of EPFRs, because of their insufficient Lewis acidity. Our results suggest that the surface species rather than Lewis acid sites may be a major contributor to the formation of EPFRs on metal oxides like Fe2O3.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
MICROCHIMICA ACTA
·
2017
·Vol. 184
·期 6
·1817-1825
·
IF 4.58
Li Qiu-Lin,Huang Fang,Wang Xiao-Li,Wang Xia,Zhao Ru-Song
The high performance solid-phase microextraction (SPME) of polar phenols from aqueous matrices is a challenge due to the strong interaction between water molecules and polar phenols. The authors describe the fabrication of stainless steel fibers coated with multiple helix 3D metal-organic nanotubes via physical adhesion, and their application to the SPME of 2-chlorophenol, 2-nitrophenol, 2,4-dichlorophenol, 4-chloro-3-methylphenol and 2,4,6-trichlorophenol from water samples. GC/MS was used for sample quantification and detection. Box-Behnken design was adopted to optimize the experimental conditions through response surface methodology. The fibers display good thermal stability (~400 °C), high enrichment factors (418–1874), excellent repeatability (4.31%–8.37%), wide linear range (0.5–1000 ng⋅L −1 ) and low limits of detection (0.07–0.18 ng⋅L −1 ) for the phenols. This method was successfully applied to the analysis of phenols in environmental water samples.
Multiple helix 3D metal-organic nanotubes coated stainless steel fibers were fabricated. The fibers achieved good thermal stability (~400 °C), high enrichment factors (418–1874), excellent repeatability (4.31–8.37%), wide linear range (0.5–1000 ng L −1 ) and low limits of detection (0.07–0.18 ng L −1 ) for phenols.
研究领域:
分析化学
·
环境科学
✓ 已验证
DOI
高影响因子
JOURNAL OF LIQUID CHROMATOGRAPHY & RELATED TECHNOLOGIES
·
2017
·
IF 0.697
Xiaoting Zhang,Jiahua Niu,Yixin Yang,Peige Qin,Shufang Tian,Jinhua Zhu,Minghua Lu
In this work, a magnetic solid-phase extraction protocol followed with high-performance liquid chromatography analysis was developed for the determination of maltol and ethyl maltol in food samples. The Fe3O4 nanoparticles were prepared by one-step hydrothermal method and was used as adsorbent for clean and preconcentrated maltol and ethyl maltol in food samples. The as-prepared Fe3O4 nanoparticle was characterized by transmission electron microscope, Fourier transform infrared spectroscopy, X-ray diffraction, and vibrating sample magnetometer. The extraction conditions including the amount of material, extraction time, pH, temperature, and desorption solvents were investigated, respectively. Under the optimized conditions, the detection limits of 0.04 and 0.05 µg mL−1 could be achieved for maltol and ethyl maltol. The recoveries between 84.2 and 103.4% with RSDs lower than 2.30% were obtained for the analysis of spiked plum candy sample. The developed method was successfully applied to the analysis of real samples, such as juice, chocolate, and plum candy.
研究领域:
分析化学
·
食品科学
✓ 已验证
DOI
高影响因子
Analytical Methods
·
2014
·Vol. 6
·期 18
·7420-7425
·
IF 1.938
Zhuo Li,Ruiling Sun,Yongnian Ni,Serge Kokot
An efficient method for the analysis of hydroquinone at trace levels in water samples has been developed in the form of a fluorescent probe based on graphene quantum dots (GQDs). The analytical variable, fluorescence quenching, was generated from the formation of benzoquinone intermediates, which formed during the catalytic oxidation of hydroquinone by horseradish peroxidase (HRP). In general, the reaction mechanism involved hydroquinone, as an electron acceptor, which affected the surface state of GQDs via an electron transfer effect. The water-soluble GQDs were directly prepared by the pyrolysis of citric acid and with the use of the mentioned hybrid enzyme system, the detection limit for hydroquinone was as low as 8.4 × 10−8 M. Furthermore, this analysis was almost unaffected by other phenol and quinine compounds, such as phenol, resorcinol and other quinines, and therefore, the developed GQD method produced satisfactory results for the analysis of hydroquinone in several different lake water samples.
研究领域:
分析化学
·
环境科学
·
生物化学
✓ 已验证
DOI
高影响因子
Nanotechnology Reviews
·
2022
·Vol. 11
·期 1
·3095-3103
·
IF 6.739
Jie Ding,Yingluo Zhuang,Minxian Shi,Zhixiong Huang,Yan Qin,Yan Li,Cunku Wang
In this article, nano-ZrSi 2 -modified phenolic (Ph) resin and nano-ZrSi 2 -modified quartz–phenolic (Q–Ph) composites are, respectively, prepared by resin casting and compression molding. The effect of nano-ZrSi 2 on the thermal stability of Ph resin and the role of nano-ZrSi 2 on the thermal reusability of Q–Ph composites are investigated by multiple thermal gravimetric analyses and mechanical tests. The strengthening mechanism of nano-ZrSi 2 modification is investigated by the evolution of microstructure. The results show that the addition of nano-ZrSi 2 enhances the thermal stability of Ph resin under repeated heating at 1,200°C in air. The enhancement in thermal stability of resin exhibits a positive effect on improving the thermal reusability of composites. Within the range of 20 repeated heating times, the flexural strength of nano-ZrSi 2 -modified composites is above 16.01 MPa, which is 163.8% higher than that of unmodified composites. The strengthening mechanism of nano-ZrSi 2 is mainly in the inhibition of thermal oxidation and the reduction of microstructural defects during the repeated thermal environment.
研究领域:
材料科学
·
热力学工程
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Wen-Long Yu,Shi-Lei Zhao,Guang-Wen Xu,Xin Li,Xiao-Lei Zhang,Yu-Ling Shan,Jun-Wei Ding,Guo-Hui Qin,Jun-Mei Zhang,Xiang Feng,De Chen
The chloroxylenol (PCMX) has shown well virucidal efficacy against COVID-19, but the large-scale utilization of which will undoubtedly pose extra environmental threaten. In the present study, the recycled industrial phenylenediamine residue was used and an integrated strategy of “carbonization-casting-activation” using super low-dose of activator and templates was established to achieve in-situ N/O co-doping and facile synthesis of a kind of hierarchical hyperporous carbons (HHPC). The sample of HHPC-1.25–0.5 obtained with activator and template to residue of 1.25 and 0.5 respectively shows super-high specific surface area of 3602 m 2 /g and volume of 2.81 cm 3 /g and demonstrates remarkable adsorption capacity of 1475 mg/g for PCMX in batch and of 1148 mg/g in dynamic column adsorption test. In addition, the HHPC-1.25–0.5 exhibits excellent reusability and tolerance for PCMX adsorption under various ionic backgrounds and real water matrix conditions. The combined physio-chemistry characterization, kinetic study and DFT calculation reveal that the enhanced high performances originate from the hierarchical pore structure and strong electrostatic interaction between PCMX and surface rich pyridinic-N and carbonyl groups.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
MICROCHIMICA ACTA
·
2013
·Vol. 180
·期 5
·461-468
·
IF 3.434
Ma Xuemei,Liu Zhaona,Qiu Cuicui,Chen Ting,Ma Houyi
We have synthesized a virtually monodisperse gold-graphene (Au-G) nanocomposite by a single-step chemical reduction method in aqueous dimethylformamide solution. The nanoparticles are homogenously distributed over graphene nanosheets. A glassy carbon electrode was modified with this nanocomposite and displayed high electrocatalytic activity and extraordinary electronic transport properties due to its large surface area. It enabled the simultaneous determination of hydroquinone (HQ) and catechol (CC) in acetate buffer solution of pH 4.5. Two pairs of well-defined, quasi-reversible redox peaks are obtained, one for HQ and its oxidized form, with a 43 mV separation of peak potentials (ΔE p ), the other for CC and its oxidized form, with a ΔE p of 39 mV. Due to the large separation of oxidation peak potentials (102 mV), the concentrations of HQ and CC can be easily determined simultaneously. The oxidation peak currents for both HQ and CC increase linearly with the respective concentrations in the 1.0 μM to 0.1 mM concentration range, with the detection limits of 0.2 and 0.15 μM (S/N = 3), respectively. The modified electrode was successfully applied to the simultaneous determination of HQ and CC in spiked tap water, demonstrating that the Au-G nanocomposite may act as a high-performance sensing material in the selective detection of some environmental pollutants.
Au-graphene (Au-G) nanocomposites were synthesized through a single-step chemical reduction method. Nearly monodispersed Au nanoparticles were uniformly distributed over the 2D graphene nanosheets without aggregation. The glassy carbon electrode modified with Au-G nanocomposites, Au-G/GCE, shows high resolution capability in simultaneous determination of hydroquinone (HQ) and catechol (CC) in acetate buffer solutions (HAc-NaAc, pH 4.5).
研究领域:
分析化学
·
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL POLLUTION
·
2020
·
IF 6.793
Xulei Zhao,Teng Zhang,Junhe Lu,Lei Zhou,Jean-Marc Chovelon,Yuefei Ji
Sulfate radical (SO 4 − )-based advanced oxidation processes (SR-AOPs) are promising in-situ chemical oxidation technologies widely applied for soil/groundwater remediation. The presence of non-target water constituents may interfere the abatement of contaminants by SR-AOPs as well as result in the formation of unintended byproducts. Herein, we reported the formation of toxic chloronitrophenols during thermally activated persulfate oxidation of 2-chlorophenol (2CP) in the presence of nitrite (NO 2 − ). 2-Chloro-4-nitrophenol (2C4NP) and 2-chloro-6-nitrophenol (2C6NP) were identified as nitrated byproducts of 2CP with total yield up to 90%. The formation of nitrated byproducts is a result of coupling reaction between 2CP phenoxyl radical (ClPhO ) and nitrogen dioxide radical (NO 2 ). As a critical step, the formation of ClPhO was supported by density functional theory (DFT) computation. Both 2C4NP and 2C6NP could convert to 2-chloro-4,6-dinitrophenol (2C46DNP) upon further treatment via a denitration-renitration process. The formation rate of 2C4NP and 2C6NP was closely dependent on the concentration of NO 2 − , solution pH, and natural water constituents. ECOSAR calculation suggests that chloronitrophenols are generally more hydrophobic and ecotoxic than 2CP. Our result therefore reveals the potential risks in the abatement of chlorophenols by SR-AOP, particularly when high level of NO 2 − is present in water matrix.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）