EUROPEAN FOOD RESEARCH AND TECHNOLOGY
·
2018
·Vol. 244
·期 11
·2007-2017
·
IF 1.919
Bai Shuang,Cui Can,Liu Jing,Li Pei,Li Qing,Bi Kaishun
The objective of the research was to evaluate potential biological activities of Portuguese red wines with different grape types on the level of composition characterization. An ultrafast liquid chromatography coupled with triple quadrupole mass spectrometry method was validated and used for qualitative analysis of commercial red wine samples through simultaneously determining 31 major active components. Meanwhile, the antioxidant activities of red wines were measured by DPPH (1,1-diphenyl-2-picrylhydrazyl), ABTS [2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid)] and CUPRAC (cupric ion reducing antioxidant capacity) assay. The relations between polyphenols and antioxidant values were further considered by multivariate statistical analysis. Results of correlation analysis and stepwise multiple regression analysis showed that antioxidant activities were highly correlated to polyphenolic profiles, with significant contributions of procyanidins and phenolic acids. Consequently, the assessment method we established appeared to be an effective tool for appraising the nutritional value of polyphenols in wines, and the research strategy could be applied to the evaluation of other beverages.
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高影响因子
JOURNAL OF POLYMER RESEARCH
·
2018
·Vol. 25
·期 7
·1-7
·
IF 1.434
Yang Xiaowu,Wang Xia,Wang Chen
Amphipathic comb-like fluoropolymer (P(OEGMA-co-FHA)) based on oligomer (ethylene glycol) methacrylate (OEGMA) and 3,3,4,4,5,5,6,6,6-nonafluorohexyl acrylate (FHA) monomers was prepared by atom transfer radical polymerization, which was first characterized by Fourier-transform infrared spectroscopy and ( 9 F, 1 H) nuclear magnetic resonance. And their aggregation behaviors at different temperatures were studied by transmittance,fluorescence spectroscopy,dynamic light scattering,transmission electron microscopy, small angle X-ray scattering and rheology. The results show that P (OEGMA-co-FHA) has thermal responsiveness, which leads to changes in aggregation behaviors with the increase of temperature. Low critical solution temperature (LCST) was 45 °C. The critical associating concentration (CAC) values are 1.85 and 1.61 g/L at room temperature and 35 °C respectively. Moreover, the particles of P (OEGMA-co-FHA) was about 20 nm at room temperature and aggregated to about 100 nm at 60 °C. The viscosity of P (OEGMA-co-FHA) increase and had stronger shear-thin behaviors.
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ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2018
·Vol. 25
·期 26
·26259-26266
·
IF 2.8
Lei Jinfeng,Deng Lei,Li Xinying,Xu Yongbin,Li Defu,Mu Changdao
TiO 2 shows great potential as ideal and powerful photocatalyst to degrade and eliminate harmful organic pollutants from waste water. It is desirable to prepare anatase TiO 2 with good aqueous solubility and photocatalytic activity for water decontamination. In this paper, water-soluble TiO 2 nanoparticles were successfully prepared using polytetramethylene ether glycol (PTMG), poly(ethylene glycol) (PEG), and poly(propylene glycol) (PPG) as stabilizers. The anatase phase of TiO 2 was well controlled by introduction of HCl in the reaction system. The results showed that all the polymer-capped TiO 2 were well dissolved in water and their aqueous solutions could maintain stable for more than 2 months. The photocatalytic activities of polymer-capped TiO 2 were evaluated by monitoring the degradation of Rhodamine B (RhB) with Degussa P25 as a control. The results showed that all the polymer-capped TiO 2 presented better photocatalytic activity than that of Degussa P25. PTMG capped TiO 2 exhibited the longest average lifetime of charge carriers, indicating the lowest charge recombination rate. Thus, PTMG capped TiO 2 presented the best photocatalytic activity. In summary, PTMG, PEG, and PPG can be used as stabilizers to prepare water-soluble TiO 2 . PTMG is an ideal stabilizer for the synthesis of water-soluble TiO 2 with good photocatalytic activity.
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PubMed
高影响因子
POLYMER BULLETIN
·
2018
·Vol. 76
·期 5
·2215-2231
·
IF 1.589
Yu Lili,Yao Lin,Li Li,Liu Shaojing,Jia Zhengxuan,Wu Di
The cationic photo-responsive polymeric micelles (mPEG-b-p(DEMA-co-MMA-CL)) with light-switchable cross-linker were designed and fabricated by atom transfer radical polymerization and quaternization. These micelles were well dispersed spherical with positive charge. The efficient release of encapsulated contents can be triggered by light irradiation. No significant toxicity was observed of copolymer and its photolysis residues at concentrations up to 250 μg/mL. The antitumor activity of camptothecin (CPT) in micelles demonstrated that light triggered the release of CPT, which dramatically improves the cytotoxicity after UV irradiation.
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JOURNAL OF NANOPARTICLE RESEARCH
·
2018
·Vol. 20
·期 8
·1-12
·
IF 2.127
Dongmulati Naziermu,Baikeri Salamaiti,Maimaitiyiming Xieraili,Maimaiti Yumaierjiang
In this paper, we mainly studied the preparation of platinum-containing composite materials with carbon nanotubes wrapped by polypyrimidine-conjugated polymers and the performance of the composites. The polymer-based carbon nanotubes/Pt catalysts were prepared successfully and confirmed by infrared spectroscopy, XPS, XRD, and TEM images. The performance of polypyrimidine/multi-walled carbon nanotubes (MWCNTs)/Pt and polypyrimidine/double-walled carbon nanotubes (DWCNTs)/Pt was compared with the polypyrimidine/single-walled carbon nanotubes (SWCNTs)/Pt. The amount of the loaded Pt on the polypyrimidine/MWCNTs and polypyrimidine/DWCNTs was calculated to be 50.5 wt% and 52.7 wt% respectively. The effective specific surface area of the polypyrimidine/MWCNTs/Pt (45.7 m 2 /g) and polypyrimidine/DWCNTs/Pt (42.47 m 2 /g) was observed by electrochemical cyclic voltammetry. These studies strongly imply that the MWCNTs were better candidates than DWCNTs and SWCNTs in the application of polypyrimidine/CNT materials as catalyst for fuel cells.
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JOURNAL OF MATERIALS SCIENCE
·
2018
·Vol. 53
·期 22
·15430-15441
·
IF 2.993
Zhenfu Zhao,Liang Jing,Zhihai Wu,Jiong Cheng,Miaomiao Zhang,Yafei Hou
Halide perovskite quantum dots (PQDs) have been intensively studied because of their superior optical properties and have great potential applications in laser, display technology and light-emitting diodes (LEDs). Presently, high-efficiency green emissive CH 3 NH 3 PbBr 3 PQDs have been successfully fabricated. However, the synthesis of stable iodide-based CH 3 NH 3 PbX 3 (MAPbX 3 (X = Cl, Br, I), MA = CH 3 NH 3 ) QDs still faces significant challenges because they are sensitive to the moisture in open air. Herein, we investigated the effect of the solvent and ligand on the growth of the as-prepared MAPbBr 3 and MAPbI 3 sample, mainly involved in the volume ratio of N , N -dimethylformamide (DMF) and γ-butyrolactone (GBL) and the amount of n -octylamine in toluene. The results show that the low volume ratio of DMF and GBL is beneficial to prepare highly luminescent, stable and full-colored MAPbX 3 PQDs in open air. Besides, the PL emission peak of MaPbBr 3 PQDs can be adjusted from 430 to 513 nm via precisely controlling the amount of n -octylamine in toluene because of quantization. The obtained MAPbX 3 PQDs show high quantum yield and a wide range of tunable light emission from ultraviolet to near-infrared region. The MAPbX 3 PQDs, especially iodide-based MAPbX 3 PQDs, obtained from this method remain stable more than 3 months at ambient condition. We further demonstrated the multi-colored LEDs by using different color emissive MAPbX 3 PQDs as color converters and being subjected to excitation through a blue GaN chip. Furthermore, MAPbX 3 PQDs are expected to show interesting nanoscale optical properties and have great potential applications in electroluminescence devices, lasers and optical sensors.
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CHEMICAL RESEARCH IN CHINESE UNIVERSITIES
·
2018
·Vol. 34
·期 4
·571-577
·
IF 1.248
Han Xie,Shao Kaiyuan,Hu Wenxiang
Hyperglycemia is frequently accompanying with hyperlipidemia. To explore the potent drugs with dual-activity and dual-site effects that could reduce blood glucose and blood lipid at the same time, fibrate group with lipid-lowering effect on the 9th position of berberine(BBR) was introduced using the drug design combination principle and the multitarget collaborative treatment method. Moreover, the molecular structure of BBR was modified, and six 9-substituted derivatives of BBR were designed and synthesized, among which, five compounds have never been reported before. In addition, the molecular structures of these derivatives were identified using liquid chromatography-mass spectrometry(LC-MS), 1 H nuclear magnetic resonance( 1 H NMR) and 13 C NMR, respectively. Furthermore, the microwave irradiation experimental technique was applied in the synthesis reaction using the novel microwave synthesizer, which accelerated the reaction rate, enhanced the reaction yield, reduced the reaction by-products, and simplified the post-processing steps. In the meantime, the 9-position regioselective demethylation of BBR was explored through quantum chemical calculation during the synthesis of berberrubine. The computations were consistent with the experimental results, which contributed to deducing the mechanism of its selective methylation.
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高影响因子
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
·
2018
·Vol. 135
·期 6
·3363-3373
·
IF 2.209
Zhang Shijie,Zhang Jiaoqiang,Kou Kaichang,Jia Qian,Xu Yunlong,Zerraza Sofiane,Liu Ning,Hu Rongzu
2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexazisowurtzitane (HNIW)·1,3,5,7-tetranitro-1,3,5,7-tetrazocane (HMX) co-crystal in a 2:1 molar ratio was prepared by a solvent/non-solvent method, and the co-crystal has been characterized by several methods. The enthalpies of dissolution of 2HNIW·HMX co-crystal in N,N -dimethylformamide at different temperatures were measured by a DC08-1 Calvet microcalorimeter under standard atmospheric pressure, and it is indicated that the dissolutions are exothermic process. The empirical formulae for the calculation of the molar enthalpy ( \(\Delta_{\text{diss}} H\) ) of dissolution, relative partial molar enthalpy ( \(\Delta_{\text{diss}} H_{\text{partial}}\) ), relative apparent molar enthalpy ( \(\Delta_{\text{diss}} H_{\text{apparent}}\) ), and enthalpy of dilution ( \(\Delta_{\text{dil}} H_{1,2}\) ) at 298.15 K are obtained. The differential enthalpies ( \(\Delta_{\text{dif}} H\) ) and kinetic equations describing the dissolution process at different temperatures are deduced. Furthermore, the apparent activation energy E = 10.54 ± 0.22 kJ mol -1 and pre-exponential constant A = 0.34 ± 0.03 s −1 of 2HNIW·HMX co-crystal are obtained. The standard molar Gibbs free energy of activation ( \(\Delta G_{ \ne }^{\theta }\) ) at different temperatures is 86.44 ± 0.02 kJ mol −1 (298.15 K), 88.02 ± 0.03 kJ mol −1 (303.15 K), 89.61 ± 0.01 kJ mol −1 (308.15 K), 91.18 ± 0.01 kJ mol −1 (313.15 K), and 92.75 ± 0.02 kJ mol −1 (318.15 K), respectively. The standard molar entropy of activation ( \(\Delta S_{ \ne }^{\theta }\) ) and standard molar enthalpy of activation ( \(\Delta H_{ \ne }^{\theta }\) ) are − 262.55 ± 0.72 J mol −1 K −1 and 7.98 ± 0.22 kJ mol −1 , respectively.
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Journal of Inorganic and Organometallic Polymers and Materials
·
2019
·Vol. 29
·期 6
·1874-1885
·
IF 1.637
Wang Hongpeng,Lin Yuecheng,Li Yin,Dolgormaa Anudari,Fang Hui,Guo Lin,Huang Jun,Yang Junxing
To improve the adsorption capacity of Cd(II) ions, Cd(II) ions were imprinted on the surface of aminoethyl chitosan (AECS), which was coated on Fe 3 O 4 @SiO 2 nanoparticles. A novel magnetic Cd(II) ion-imprinted polymer (Cd(II)-IIP) was synthesized, characterized, and applied to the selective separation of Cd(II) ions from aqueous solution. The adsorption–desorption properties and selectivity of Cd(II)-IIP and a non-imprinted polymer (Cd(II)-NIP) were investigated. The optimum pH and equilibrium binding time were established at pH 6.0 and 60 min, respectively. Kinetics studies demonstrated that the adsorption process proceeded according to a pseudo-first or second order model, while the adsorption isotherms agreed with the Langmuir model. The maximum adsorption capacities of Cd(II)-IIP and Cd(II)-NIP toward Cd(II) ions, as calculated by the Langmuir equation, at pH 6.0 and 25 °C were 26.1 and 6.7 mg/g, respectively. The imprinted polymer showed higher selectivity toward Cd(II) ions compared to the non-imprinted polymer. The relative selectivity factor ( β r ) values of Cd(II)/Cu(II), Cd(II)/Cr(II), and Cd(II)/Pb(II) were 3.315, 3.875, and 2.061, respectively. In addition, Cd(II) ions adsorbed on the Cd(II)-IIP adsorbent could be easily released using 0.1 M HNO 3 , thus showing good material stability and reusability. The adsorption capacity of Cd(II)-IIP was retained at 74% after undergoing six adsorption–desorption cycles.
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Nanoscale Research Letters
·
2019
·Vol. 14
·期 1
·1-10
·
IF 3.159
Tian Yefei,Lei Miao
Photothermal therapy (PTT) that utilizes phSUPPotothermal conversion agents (PTC) to ablate tumor under NIR light irradiation has attracted increasing attention due to its excellent therapeutic efficacy and improved target selectivity. Herein, a novel core-shell nanoparticle based on disulfide-crosslinked poly(methacrylic acid) (PMAA) layer coated polydopamine (PDA) particle has been successfully synthesized by precipitation polymerization. For these PDA@PMAA composite nanoparticles, PDA core exhibits high photothermal efficacy, meanwhile, the redox-labile PMAA shell serves as carriers to encapsulate anticancer drugs and selectively release them. Due to the characteristic of the disulfide bond, PMAA shell occurs at selective degradation as well as controlled drug release upon entering cancer cells. Moreover, the DOX-loaded PDA@PMAA nanoparticles demonstrated a synergistic effect, which shows a significantly improved inhibition effect against cancer cells by the combination of photothermal therapy and traditional chemotherapy with low drug dosage and short laser irradiation in an in vitro study.
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PubMed
高影响因子
CELLULOSE
·
2019
·Vol. 26
·期 9
·5455-5466
·
IF 3.917
Dang Baokang,Chen Yipeng,Shen Xiaoping,Jin Chunde,Sun Qingfeng,Li Xiurong
An Fe 3 O 4 -modified lignocellulose (FeLC) composite was fabricated via a sol–gel-assisted hot-pressing process and used for microwave-absorbing and structural materials. The Fe 3 O 4 nanoparticles could be formed in situ at the interface of the lignocellulose (LC) during sol–gel and hot-pressing processing. The obtained FeLC composites exhibited good mechanical and microwave absorption properties. The maximum reflection loss values of the FeLC composite reached − 10.97 dB at 17.04 GHz, and the effective electromagnetic wave absorption reached 90%. Compared with the modulus of rupture (MOR) and modulus of elasticity (MOE) of the LC composite, the maximum MOR and MOE values of the FeLC composite were 26.50 ± 1.16 MPa and 3.015 ± 0.25 GPa, respectively, increasing by 30.2% and 62.1%, respectively. Therefore, the properties of the FeLC could be enhanced via sol–gel assisted hot-pressing.
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Nature Energy
·
2019
·Vol. 4
·期 5
·408-415
·
IF 54
Li Nengxu,Tao Shuxia,Chen Yihua,Niu Xiuxiu,Onwudinanti Chidozie K.,Hu Chen,Qiu Zhiwen,Xu Ziqi,Zheng Guanhaojie,Wang Ligang,Zhang Yu,Li Liang,Liu Huifen,Lun Yingzhuo,Hong Jiawang,Wang Xueyun,Liu Yuquan,Xie Haipeng,Gao Yongli,Bai Yang,Yang Shihe,Brocks Geert,Chen Qi,Zhou Huanping
Defects play an important role in the degradation processes of hybrid halide perovskite absorbers, impeding their application for solar cells. Among all defects, halide anion and organic cation vacancies are ubiquitous, promoting ion diffusion and leading to thin-film decomposition at surfaces and grain boundaries. Here, we employ fluoride to simultaneously passivate both anion and cation vacancies, by taking advantage of the extremely high electronegativity of fluoride. We obtain a power conversion efficiency of 21.46% (and a certified 21.3%-efficient cell) in a device based on the caesium, methylammonium (MA) and formamidinium (FA) triple-cation perovskite (Cs 0.05 FA 0.54 MA 0.41 )Pb(I 0.98 Br 0.02 ) 3 treated with sodium fluoride. The device retains 90% of its original power conversion efficiency after 1,000 h of operation at the maximum power point. With the help of first-principles density functional theory calculations, we argue that the fluoride ions suppress the formation of halide anion and organic cation vacancies, through a unique strengthening of the chemical bonds with the surrounding lead and organic cations.
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