APPLIED SURFACE SCIENCE
·
2020
·
IF 6.182
Xukang Wang,Zhigao Huang,Minlong Lai,Lin Jiang,Yun Zhang,Huamin Zhou
The weak interfacial adhesion between carbon fibers (CFs) and poly(ether ether ketone) (PEEK) strongly hinders the true potential of composites in high performance applications. Herein, a novel heterocyclic derivative of PEEK was utilized as a linkage between CFs surface and PEEK matrix by a facile and high effective two-step method. CFs were firstly grafted with sodium sulfonate groups via aryl diazonium treatment, and then modified by the sizing agent poly(aryl indole ketone) (PAIK). This promising method takes advantages of strong cation-π interaction between PAIK and activated CFs, increased surface roughness of CFs, as well as good compatibility between PAIK and PEEK. As a result, the tensile strength and interlaminar shear strength (ILSS) of CF/PEEK composites were both improved after aryl diazonium treatment and PAIK sizing. The highest ILSS obtained for the 1 wt% PAIK modified CF/PEEK composites, which was 62.97% higher than that of untreated CFs based composites. Finally, the interfacial reinforcing mechanism in modified composites was proposed by analyzing the interfacial microstructure. This research provided a promising approach to produce high performance CF reinforced thermoplastic polymeric composites.
研究领域:
材料科学
·
复合材料
✓ 已验证
产品关联
DOI
高影响因子
PLANT PHYSIOLOGY AND BIOCHEMISTRY
·
2018
·
IF 2.718
Hai-Na Yu,Xin-Yan Liu,Shuai Gao,Bin Sun,Hong-Bo Zheng,Mei Ji,Ai-Xia Cheng,Hong-Xiang Lou
Chalcone synthases (CHSs) of the type III polyketide synthases (PKSs), catalyze the formation of a tetraketide intermediate from a CoA-tethered starter and malonyl-CoA but use different cyclization mechanisms to produce distinct chemical scaffolds. Herein, we characterized CHS and CHS-like enzymes (designated MpCHS and MpCHSL1, 2 and 3) from Marchantia paleacea and determined the crystal structure of MpCHSL1. MpCHS catalyzed a Claisen condensation to form chalcone , while MpCHSLs catalyzed the formation of lactonized α-pyrones in vitro. Based on the structural, mutational and in vitro biochemical analyses, we established that MpCHSL1 is structurally and functionally closer to prototype CHS than stilbene synthase , and characterized the structural basis for the functional diversity of the type III PKSs. A chalcone-forming mutant of MpCHSL1 was build directed by the structural information. These findings pave the way for future studies to elucidate the functional diversity of type III PKSs in liverwort .
研究领域:
植物生物化学
·
分子生物学
·
酶学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2018
·
IF 2.21
Zhiming Zhang,Tingting Li,Yuqing Li,Li Yan,Libao An
Novel thiolation poly (phthalazinone ether ketone) (PPEK-SH) nanofibrous membrane (NFM) was successfully fabricated via grafting and electrospinning. The PPEK-SH NFM with high glass transition temperature (324.4 °C), robust tensile strength (12.48 MPa), high porosity (89.5%) and superior chemical resistance was employed as support of Au nanoparticles (NPs) for preparing electrocatalyst . Au NPs were deposited on the NFM via electroless plating and characterized by SEM, EDX , TEM and XRD . The as-prepared Au/PPEK-SH NFM inherited the excellent properties of PPEK-SH NFM and good conductivity of Au, thereby was successfully used as a free-standing electrocatalyst without resorting to any conductive support. The free-standing NFM exhibited excellent electrocatalytic activity towards glycerol oxidation with high oxidation peak of 74.2 mA cm −2 and low onset potential of −0.34 V. More importantly, benefiting from the strong chemical interaction between Au and -SH, Au/PPEK-SH NFM presented an incredible stability during the process of glycerol electrooxidation. Only 2.7% decrease of the peak current density was observed after 100 cycles of experiments, indicating that the free-standing electrocatalyst had great potential for long-term use. This work may provide a new approach for the development of stable free-standing electrocatalyst based on electrospun nanofibers in the application of direct alcohol fuel cells.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ETHNOPHARMACOLOGY
·
2013
·
IF 2.755
Linling Lu,Dawei Qian,Jianming Guo,Yefei Qian,Boyi Xu,Mei Sha,Jinao Duan
Aim Abelmoschi Corolla is a well-known herbal medicine used for the treatment of chronic renal disease . Flavonoids are the major bioactive ingredients of Abelmoschi Corolla, but some non-flavonoid components also exist in this herb. In order to clarify the influences of non-flavonoid components on the pharmacokinetics profile of the flavonoid fraction from Abelmoschi Corolla (FFA), an investigation was carried out to compare the pharmacokinetic parameters of seven flavonoid components after administration of FFA and after administration of FFA combined with different non-flavonoid fractions. Materials and methods A selective and sensitive UPLC–MS/MS method was established to determine the plasma concentrations of the seven compounds. Sprague-Dawley rats were allocated to four groups which orally administered FFA, FFA combined with macromolecular fraction (FFA–MF), FFA combined with small molecule fraction (FFA–SF) and FFA combined with MF–SF (FFA–MF–SF) with approximately the same dose of FFA. At different time points, the concentration of rutin (1), hyperoside (2), isoquercitrin (3), hibifolin (4), myricetin (5), quercetin-3′- O -glucose (6), quercetin (7) in rat plasma were determined and main pharmacokinetic parameters including T 1/2 , T max , AUC and C max were calculated using the DAS 2.0 software package. The statistical analysis was performed using the Student's t -test with P <0.05 as the level of significance. Results Flavonoids almost had similar pharmacokinetics profile that were rapidly absorbed, reached the peak concentration at 30–60 min in group A, but the pharmacokinetic profiles and parameters of these flavonoids changed when co-administered with non-flavonoid components. It was found that AUC of five flavonoids but not hibifolin and quercetin in group FFA–SF and group FFA–MF–SF increased ( P <0.05) in comparison with group FFA while the tendency was not observed in group FFA–MF. Moreover, seven flavonoids had varying degrees of differences in the pharmacokinetics parameters such as C max , T max and T 1/2 ( P <0.05) in group FFA–MF, FFA–SF and FFA–MF–SF by comparison with group FFA. Conclusion These results indicate that non-flavonoid components could improve the bioavailability and delay the elimination of some flavonoids in rat.
研究领域:
中药学
·
药理学
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2024
·
IF 8.5
Hanliang Li,Lianzhu Lin,Mouming Zhao
This study aimed at recycling flavonoids with glycolipid lowering activity from Chenpi processing residue produced by essential oil extraction. The crude Chenpi flavonoids obtained by ethanol reflux mainly contained flavonone (hesperidin) and polymethoxyflavonoids (nobiletin, tangeretin, sinensetin, and isosinensetin), which complementally exerted strong glycolipid lowering activity as revealed by digestive enzyme inhibitory activity, molecular docking and network pharmacology. The reducing sugar and water-soluble impurities were efficiently removed by yeast fermentation and aqueous two-phase system (ATPS) extraction, respectively. The optimal combination use of yeast (2 % w / v , CN36) and ATPS formed by 22 % ( w /w) (NH 4 ) 2 SO 4 and 25 % (w/w) ethanol improved flavonoid purity to 60.25 %, enriched flavonone and polymethoxyflavonoids by 6.69-fold, and enhanced digestive enzyme inhibitory activity, which was superior to the use of individual yeast or ATPS, unoptimized combination, macroporous resin (XAD-16), and ethyl acetate. This study was the first to develop a recyclable biophysical method for simultaneous enrichment of flavonone and polymethoxyflavonoids.
研究领域:
药学
·
生物技术
·
食品科学
·
药理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Wentao Liu,Chengde Liu,Cheng Liu,Yizheng Li,Liang Pan,Jinyan Wang,Xigao Jian
Failure of poly(aryl ether ketone) (PAEK) bone implants results mainly from poor osteogenesis and bacterial infection. One promising strategy for enhancing osteointegration involves developing a bioactive surface of PAEK implants through chemical modification. Poly(phthalazinone ether nitrile ketone) (PPENK) is considered a potential PAEK bone implant because it possesses mechanical properties similar to those of natural bone and its cyano group has high reactivity which provides a surface modification strategy. In this work, recombinant human bone morphogenetic protein-2 (rhBMP-2) and newly synthesized cationic antimicrobial polypeptides (AMPs) were chemically conjugated to a PPENK substrate surface to enhance osteogenic and antibacterial activities. The molecular structures of AMP-1 and AMP-2 containing PEG segments were confirmed by nuclear magnetic resonance spectroscopy. The surface roughness of each substrate was reduced by rhBMP-2 and AMP immobilization. In situ, real-time quartz crystal microbalance with dissipation studies revealed that the loading amount increased with the successive immobilization of rhBMP-2 and AMPs. In vitro antibacterial assay confirmed that the AMP-modified PPENK surfaces provided an effective antibacterial effect and the number of residential bacteria remaining on the substrate was reduced by the PEG segments in AMP-2. In vitro osteogenic properties of the rhBMP-2-modified PPENK surface presented favorable cytocompatibility and osteo-inductive activity. In vivo studies confirmed that the rhBMP-2 and AMP immobilization led to decrease amounts of fibrous tissues around the implant and improved bone regeneration. This study provides a strategy for surface modification that enhances the antibacterial and osteogenic activities to develop a bone implant material with considerable potential for clinical application.
研究领域:
材料科学
·
生物材料
·
组织工程
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
ORGANIC & BIOMOLECULAR CHEMISTRY
·
2017
·Vol. 15
·期 16
·3427-3434
·
IF 3.564
Dan Wang,Kuan Zhang,Luhan Jia,Danting Zhang,Yue Zhang,Yujia Cheng,Chang Lin,Bo Wang
Presented here is the first example of synthesizing an array of primary-, secondary-, and tertiary-α-ketoamides with a non-metal catalyst nBu4NI from methyl ketones and inexpensive readily available amine/ammonium salts; the reactions proceeded smoothly under mild conditions, TBHP was used as an oxidant and the corresponding α-ketoamides were afforded in moderate to excellent yields.
研究领域:
有机化学
·
催化化学
✓ 已验证
DOI
PubMed
高影响因子
MATERIALS LETTERS
·
2017
·
IF 2.572
Baolin Wang,Meidi Wang,Ming-Wei Chang,Zesshan Ahmad,Jie Huang,Jing-song Li
Multi-compartment fibers with well-defined regions and functional media hosting potential provide co-encapsulation opportunities for a variety of bio-molecules, drugs and even nutrients. In this research, fibers possessing multiple compartments were prepared using the single-step electrospinning method and a modified non-concentric multi-needle. Polyvinyl pyrrolidone (PVP) was used as the fiber shell material, while ketoconazole (KCZ, model drug) and Sudan Red (model probe) were encapsulated as two separate segments running along the fiber length. Multi-compartment fiber morphology and structure were examined using optical and electron microscopy. The effect of flow rate on fiber morphology was also investigated and the release of encapsulated KCZ and Sudan Red was examined using UV spectroscopy. The results present an efficient and promising method to engineer multi-compartment fibers in a single step for several biomedical applications in lieu .
研究领域:
材料科学
·
生物医学工程
✓ 已验证
DOI
高影响因子
International Journal of Environmental Research and Public Health
·
2018
·Vol. 15
·期 9
·1907
·
IF 2.145
Wen-Qian Wang,Hai-Xin Duan,Zhou-Tao Pei,Rou-Rou Xu,Ze-Tian Qin,Guang-Can Zhu,Li-Wei Sun
Ultraviolet absorbing chemicals (UV filters) are widely used in personal care products for protecting human skin and hair from damage by UV radiation. Although these substances are released into the environment during production and consumption processes, little is known about their genotoxicity effects. Our previous studies have shown that benzophenone-type UV filters exhibited acute toxicity on three species of aquatic organisms. Mutagenesis by benzophenone (BP) and benzophenone-1(BP-1) was tested in the present study by theSalmonella typhimurium/reverse mutation assay (Ames assay). All the positive reverse mutations occurred in the absence of the S9 liver extract system for both chemicals. From BP, positive mutation effects on the TA102 strain at doses of 0.05 μg/plate and 0.5 μg/plate were detected. From BP-1, positive mutation effects on the TA97 strain at doses of 0.05 μg/plate and 0.5 μg/plate, and on the TA100 strain at a dose of 0.5 μg/plate, were detected. A mixture of BP and BP-1 exhibited mutagenicity on the TA97 and TA100 strains. For the TA97 strain, the positive mutation results were detected at 10% and 50% of the mixture. For the TA100 strain, the results were detected when the mixture was at 5% and 10%. In the mixture at 5%, the concentrations of BP and BP-1 were 3.5 μg/plate and 14 μg/plate, respectively. In the 10% mixture, the doses of BP and BP-1 were 7 μg/plate and 28 μg/plate, respectively. In the 50% mixture, the doses of BP and BP-1 were 35 μg/plate and 140 μg/plate, respectively. The mixture test results suggested that there was antagonism in mutagenicity between BP and BP-1.
研究领域:
毒理学
·
环境科学
·
遗传学
✓ 已验证
DOI
高影响因子
GREEN CHEMISTRY
·
2016
·Vol. 18
·期 10
·3075-3081
·
IF 8.506
Dezhang Ren,Zhiyuan Song,Lu Li,Yunjie Liu,Fangming Jin,Zhibao Huo
A novel approach for the production of 2,5-hexanedione (HDN) and 3-methyl-2-cyclopenten-1-one (3-MCO) from 5-hydroxymethylfurfural (HMF) by water splitting with Zn is reported for the first time. The use of high temperature water (HTW) conditions is the key for the efficient conversion of HMF to HDN and 3-MCO. Parameters regarding the Zn amount, temperature and reaction time are optimized and HDN and 3-MCO are produced in 27.3% and 30.5% yields, respectively. The roles of HTW and ZnO obtained by oxidation of Zn in water for the conversion of HMF, together with intermediate structures, are discussed to understand the mechanism of the reaction.
研究领域:
化学工程
·
有机化学
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
·
2024
·
IF 4
Yumeng Zhai,Jinkang Ma,Xinran Liu,Fanghao Xuan,Kaiwen Hu,Shoubo Wang,Xiaoyu Feng,Lifeng Cao,Bing Teng
Two new crystals were designed and obtained: the chalcone derivative HMMP (1-(2‑hydroxy-4-methoxyphenyl)-3-(4-(methylthio)phenyl)prop‑2-en-1-one) and the flavanone derivative 7M4MC (7‑methoxy-2-(4-(methylthio)phenyl)chroman-4-one). Yellow bulk 7M4MC single crystal with dimensions of 3 × 2 × 1 mm 3 and orange-yellow needle-like HMMP single crystal were grown by solution evaporation. 7M4MC crystal belongs to the P 2 1 space group of the monoclinic structure, which has a non-centrosymmetric structure. HMMP crystal monoclinic, belongs to the P 2 1 /m space group with a centrosymmetric structure. In the 7M4MC molecule, the methoxy and methylthio groups act as electron donors (D) and the carbonyl group acts as an electron acceptor (A), forming a d -π-A-π-D structure with an electron gradient. 7M4MC exhibits a high degree of second-harmonic generation intensity (11 × KDP), a broad transmission range (600–1600 nm, >88 %), an elevated optical energy bandgap ( E g = 2.57 eV), high thermal stability ( T m = 105 °C) and excellent dielectric properties ( ε r ≈ 2.1). This work not only provides two new crystals but also offers a viable molecular design option by changing the degree of intramolecular distortion by altering the backbone structure.
研究领域:
材料科学
·
光学
·
晶体工程
✓ 已验证
DOI
高影响因子
TETRAHEDRON
·
2024
·
IF 2.1
Ling-Juan Tang,Shun-Jun Ji,Zhong-Jian Cai
The monofluoroalkenes are found widespread applications in areas such as bioactive molecules, materials science and synthetic organic chemistry, therefore, investigating efficient methodologies to construct monofluoroalkenes is still in demand. In this paper, we reported an efficient synthesis of monofluoroalkenyl substituted pyranones/pyridones by using the gem -difluorocyclopropanes ( gem -DFCPs) as monofluoroalkenyl precursors. In the presence of Palladium catalyst, the monofluoroalkenyl group was introduced into the C3 positions of pyranones/pyridones successfully. The reaction was featured with high regioselectivity, mild conditions, broad substrate scope, easy to scale up synthesis, which provided a novel avenue for the late-stagy modification of pyranones/pyridones.
研究领域:
有机化学
·
药物化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）