POLYMER TESTING
·
2019
·
IF 2.943
Xuan Yang,Qunzhang Tu,Xinmin Shen,Ming Pan,Chengming Jiang,Pengxiao Zhu,Yi Li,Pei Li,Caibing Hu
In order to improve the interfacial adhesion between the poly(p-phenylene terephthalamide) fibers and rubber matrix while enhance the fiber strength simultaneously, a mild surface modification method was presented to graft polydopamine-polyethyleneimine/graphene oxide (PDA-PEI/GO) multilayer films onto the fiber surface. In this way, PDA could be first non-covalently deposited onto the fiber surface via dopamine biomimetic modification, and then the positively charged PEI was absorbed on the PDA through Michael addition reaction. After that, the negatively GO was grafted on the surface by the layer-by-layer (LbL) assembly to construct the PDA-PEI/GO multilayer films. The results of mechanical properties tests and pull-out force tests showed that the highest single-filament tensile strength and the highest pull-out force of the modified fibers increased by 15.1% and 78.1%, respectively. The optimal time of PEI/GO multilayer for the enhancement of adhesive properties was 7 and the excessive amount of PEI/GO would lead to high aggregation to decrease the adhesive strength.
研究领域:
材料科学
·
表面化学
·
复合材料
✓ 已验证
DOI
高影响因子
ANALYTICA CHIMICA ACTA
·
2019
·
IF 5.256
Duanduan Yin,Jian Liu,Xiangjie Bo,Liping Guo
In this study, cobalt-iron selenides embedded in porous carbon nanofibers (CoFe 2 Se 4 /PCF), derived from Prussian blue analogues, was prepared as a novel phenolic sensor. The obtained CoFe 2 Se 4 /PCF nanocomposites show three-dimensional (3D) networks nanostructures that can supply a desirable conductive network to accelerate electron transfer and avoid the aggregation of CoFe 2 Se 4 nanoparticles . Electrochemical detection of hydroquinone (HQ), catechol (CC) and resorcinol (RS), at CoFe 2 Se 4 /PCF modified glassy carbon electrode (GCE) were researched. The results show the obtained 3D CoFe 2 Se 4 /PCF/GCE exhibits excellent electrochemical properties towards the simultaneous testing trace of HQ, CC and RS. The obtained electrode provides wide linear ranges of 0.5–200, 0.5–190 and 5–350 μM and low detection limit of 0.13, 0.15 and 1.36 μM for HQ, CC and RS, respectively. The as-prepared phenolic sensor displays satisfied selectivity and long-term storage stability. In addition, the constructed sensor can be used to determine HQ, CC and RS in actual samples.
研究领域:
材料科学
·
分析化学
✓ 已验证
DOI
高影响因子
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
·
2017
·Vol. 83
·期 23
·
IF 3.807
Cui-Wei Chu,Bin Liu,Na Li,Shi-Gang Yao,Dan Cheng,Jia-Dong Zhao,Ji-Guo Qiu,Xin Yan,Qin He,Jian He
Thiobencarb is a thiocarbamate herbicide used in rice paddies worldwide. Microbial degradation plays a crucial role in the dissipation of thiobencarb in the environment. However, the physiological and genetic mechanisms underlying thiobencarb degradation remain unknown. In this study, a novel thiobencarb degradation pathway was proposed in Acidovorax sp. strain T1. Thiobencarb was oxidized and cleaved at the C—S bond, generating diethylcarbamothioic S-acid and 4-chlorobenzaldehyde (4CDA). 4CDA was then oxidized to 4-chlorobenzoic acid (4CBA) and hydrolytically dechlorinated to 4-hydroxybenzoic acid (4HBA). The identification of catabolic genes suggested further hydroxylation to protocatechuic acid (PCA) and finally degradation through the protocatechuate 4,5-dioxygenase pathway. A novel two-component monooxygenase system identified in the strain, TmoAB, was responsible for the initial catabolic reaction. TmoA shared 28 to 32% identity with the oxygenase components of pyrimidine monooxygenase from Agrobacterium fabrum, alkanesulfonate monooxygenase from Pseudomonas savastanoi, and dibenzothiophene monooxygenase from Rhodococcus sp. TmoB shared 25 to 37% identity with reported flavin reductases and oxidized NADH but not NADPH. TmoAB is a flavin mononucleotide (FMN)-dependent monooxygenase and catalyzed the C—S bond cleavage of thiobencarb. Introduction of tmoAB into cells of the thiobencarb degradation-deficient mutant T1m restored its ability to degrade and utilize thiobencarb. A dehydrogenase gene, tmoC, was located 7,129 bp downstream of tmoAB, and its transcription was clearly induced by thiobencarb. The purified TmoC catalyzed the dehydrogenation of 4CDA to 4CBA using NAD+ as a cofactor. A gene cluster responsible for the complete 4CBA metabolic pathway was also cloned, and its involvement in thiobencarb degradation was preliminarily verified by transcriptional analysis.IMPORTANCE Microbial degradation is the main factor in thiobencarb dissipation in soil. In previous studies, thiobencarb was degraded initially via N-deethylation, sulfoxidation, hydroxylation, and dechlorination. However, enzymes and genes involved in the microbial degradation of thiobencarb have not been studied. This study revealed a new thiobencarb degradation pathway in Acidovorax sp. strain T1 and identified a novel two-component FMN-dependent monooxygenase system, TmoAB. Under TmoAB-mediated catalysis, thiobencarb was cleaved at the C—S bond, producing diethylcarbamothioic S-acid and 4CDA. Furthermore, the downstream degradation pathway of thiobencarb was proposed. Our study provides the physiological, biochemical, and genetic foundation of thiobencarb degradation in this microorganism.
研究领域:
环境微生物学
·
分子生物学
·
生物化学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2020
·
IF 4.65
Lin Guan,Zhipeng Zheng,Yiping Guo
Spiro-OMeTAD is one of the widely used hole-transfer materials for designing high-performance perovskite solar cells . It is reported that acid doping is an efficient and facile method to increase the conductivity of spiro-OMeTAD and accelerate its oxidation process . Besides, investigating the morphologic controlling mechanism of spiro-OMeTAD films would give a novel insight in designing the hole-transport layer (HTL) and further clarify the mechanism of acid additives. In this work, the effect of benzoic acid on the spiro-OMeTAD oxidation is studied, where the formation of the lithium benzoate phase can decrease the size of hollows in the spiro-OMeTAD film. By doping benzoic acid, the HTL exhibits faster oxidation process and better hole transfer ability. Meanwhile, the hysteresis of the perovskite solar device based on the HTL is effectively reduced via optimizing the doping content, with an improved power conversion efficiency reaching up to 16.26% under standard AM 1.5G illumination.
研究领域:
材料科学
·
太阳能
·
有机电子学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2020
·Vol. 10
·期 62
·38085-38096
·
IF 3.119
Kexin Zheng,Long Jiang,Shitao Yu,Mo Xian,Zhanqian Song,Shiwei Liu,Chao Xu
In this study, a series of polystyrene-divinylbenzene resins with precise physical structure regulation and chemical modification were successfully synthesized. The regulation of Friedel–Crafts reaction conditions resulted in several physical resins with various BET surface areas and pore structures, while the adsorption of 1,3-propanediol revealed that the molecular size and other physical properties exhibited a moderate contribution to the adsorption of hydrophilic compounds. The adsorption processes between 1,3-propanediol and nitrogen, oxygen and boron functional group modified resins were further explored, and boronic acid modified resins named PS-3NB and PS-SBT exhibited higher adsorption capacities than commercial resin CHA-111. The adsorption capacity of PS-3NB and PS-SBT reached 17.54 mg g−1 and 17.23 mg g−1, respectively, which were 37% and 35% higher than that of commercial resin CHA-111. Furthermore, the adsorption mechanism demonstrated that the content of boronic acid, solution pH and adsorbate hydrophobicity were the primary adsorption driving forces. Herein, we provided a method to modify polystyrene-divinylbenzene materials with boronic acid to selectively adsorb hydrophilic polyols via the specific affinity between boronic acid and diol molecule.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2018
·
IF 6.735
Xiaowen Xie,Xiaoguo Ma,Lihui Guo,Yinming Fan,Guolong Zeng,Mengyuan Zhang,Jing Li
A novel multi-templates molecularly imprinted polymer (MIP) was prepared on the surface of mesoporous silica coated magnetic graphene oxide (MGO@mSiO 2 ), and applied for the rapid and selective detection of alkylphenol compounds including bisphenol A (BPA), 4-tert-octylphenol (4-tert-OP) and 4-nonylphenol (4-NP) in water. The synthesized composite was characterized by Fourier transform infrared spectrometer, vibrating sample magnetometer, transmission electron microscopy and Brunauer-Emett-Teller surface area analyzer. The MIP showed high adsorption capacity, good selectivity and fast kinetic for these alkylphenols. The maximum adsorption capacities of the MIP for BPA, 4-tert-OP and 4-NP were 16.81, 35.97 and 61.73 mg g −1 , respectively, which were significantly higher than those of the non-molecularly imprinted polymer (NIP) due to the imprinting effect. The adsorption of alkylphenols reached equilibrium within 30 min, and followed pseudo-second-order kinetic model and Langmuir model well. The MIP exhibited good sorption selectivity towards BPA, 4-tert-OP and 4-NP, and could be reused 5 times. Furthermore, a new method for ultrasensitive determination of BPA, 4-tert-OP and 4-NP in water by high performance liquid chromatography was developed, using MIP-based magnetic solid-phase extraction coupled with dispersive liquid-liquid microextraction. Under the optimum conditions, the limits of detection (LODs) for BPA, 4-tert-OP and 4-NP were 0.013, 0.010 and 0.010 μg L −1 , respectively. The proposed method was used to the detection of BPA, 4-tert-OP and 4-NP in real water samples, with spiked recoveries of 81.5–104.1% and relative standard deviations (RSDs) of 1.0–7.6%, indicating the multi-templates MIP could be a promising adsorbent for separation and analysis of alkylphenols.
研究领域:
环境科学
·
分析化学
✓ 已验证
DOI
高影响因子
Energy Storage Materials
·
2020
·
IF 16.28
Zhuo Chen,Zhonghui Shen,Yang Liu,Yang Zhang,Shengliao Yan,Rui Feng,Tingting Zhao,Guanghui Zhao,Chuanxi Xiong,Lijie Dong
Flexible dielectric materials with ultrahigh energy density ( U e ) is of critical importance to reduce the size of dielectric capacitors, which has recently drawn ever-increasing attention. Herein, different from the incorporation of traditional 1D/2D inorganic nanofiller into single/multi-layer polymer matrix , a multifunctional poly ( p -phenylene terephthalamide) (PPTA)-based derivative fluxible polymer ( f -PPTA) nanocluster is selected and introduced to typical ferroelectric poly (vinylidene fluoride) (PVDF) matrix. As a novel polymer-based nanofiller, the f -PPTA nanocluster consists of self-bundled parallel sulfonated PPTA skeleton and grafted with octadecylamine polyoxyethylene ether amphiphilic (PEGO) amine ligand through ionic interaction. In the multi-arm amphiphilic PEGO, one alkyl chain with the length of 15 carbon atoms provides similar hydrophobic nature to that of PVDF, which contributes to improving the interfacial compatibility between polymer nanocluster and matrix. Furthermore, the relatively short hydrophilic chain with the length of 8 carbon atoms induces a specific necklace-like arrangement of the f -PPTA nanoclusters in PVDF matrix during film fabrication spontaneously. Consequently , an ultrahigh U e ~ 22.5 J•cm −3 of the dielectric film is acquired at 600 MV•m −1 electric field. This value is the highest reported so far among all the poly (vinylidene fluoride) (PVDF)-based dielectric nanocomposites to the best of our knowledge. In addition, the elongation at break of the film can be increased to 390%, which is over 9 times that of pure PVDF sample. This work provides a new route to PVDF-based polymer nanocomposites with ultrahigh U e and highly stretchable performance.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
Polymers
·
2021
·Vol. 13
·期 15
·2388
·
IF 4.329
Meina Xie,Daikun Jia,Jin Hu,Jiyu He,Xiangmei Li,Rongjie Yang
In this study, the aromatic acetylene compound 4-(phenylethynyl) di(ethylene glycol) phthalate (PEPE) was used as a chain extender, partially replacing 1,4-butanediol. To synthesize an intrinsic flame-retardant thermoplastic polyurethane elastomer (TPU) with an aromatic acetylene structure, PEPE was synthesized by a two-step polymerization. The flame retardancy, thermal stability, and mechanical properties of TPU were studied. The microstructure of TPU char was investigated by scanning electron microscopy to analyze the flame-retardant mechanism. The tensile strength of TPU containing 1.35 wt% PEPE was 39.2 MPa, which was almost twice as much as neat TPU, showed a dramatic decrease in the peak heat release rate and total heat release, and declined by 46.2% and 24.5%, respectively. After the flame-retardant TPU burned, a cross-linked network foaming char structure was formed. The results showed that PEPE improved the mechanical properties of TPU and conferred good stability that promoted the formation of charcoal and reduced heat release during the combustion of TPU.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
ACS Applied Polymer Materials
·
2022
·
IF 4.855
Min Liu,Zhuoer Cai,Yang Xu,Jinzhong Hu,Baiwang Sun
Rare earth-based polystyrene (PS) fluorescent microspheres, which vigorously combine the merits of rare earth elements and polystyrene microspheres, hold great potential for applications in the state-of-the-art technology and tremendous efforts have been devoted to the photoluminescence field. Herein, a 5-acrylamido-1,10-phenanthroline (Aphen) and Eu(III)-based polystyrene fluorescent microsphere was developed via a facial copolymerization strategy. The optimal complexes of Eu(β-NTA)3(Aphen) and Eu(BFA)3(TPPO)2 were fabricated as the luminescent materials. Specifically, Eu(β-NTA)3(Aphen)-PS was modified for the first time to enhance the photoluminescence property, which effectively integrated the Aphen with styrene monomer. Meanwhile, Eu(BFA)3(TPPO)2 was encapsulated into PS microspheres for the realization of Eu(BFA)3(TPPO)2-PS via an ubiquitous embedding process. The fluorescent intensity of Eu(β-NTA)3(Aphen)-PS was notably reinforced along with an increasing concentration of the rare earth complexes. However, the fluorescence intensity of Eu(BFA)3(TPPO)2-PS was decreased when the concentration was 50 mg due to the saturated solubility of the complexes. The obtained copolymerization fluorescent microspheres could prevent the premature leakage of the fluorescent complexes in a natural environment and showed an outstanding photoluminescence efficiency.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2021
·Vol. 138
·期 27
·50650
·
IF 3.125
Yongliang Guo,Yanping Zheng,Haojun Zhang,Jinfeng Cui,Junhong Guo,Baoping Yang
The polystyrene (PS) composite containing self-expanded intumescent flame retardant (polyphosphate ammonium and expandable graphite) was blended with three butyltriphenylphosphine-based chelate borates, respectively, to evaluate their effect on flame retardancy. The chemical structure of as-prepared three chelate borates was confirmed by nuclear magnetic resonance (NMR) and Fourier transform infrared spectrum (FTIR). The flame retardancy of various PS composites was evaluated by vertical burning test (UL-94), limited oxygen index (LOI), and cone calorimeter (CC). Flammability and combustion results suggested that one of chelate borates, named [BTP][BMB], made PS composite (PS4) obtain V-0 rating, 27.0 ± 0.3% LOI value, and reduction on heat release and smoke production with 17 wt% total flame retardants loading. The combustion residue was analyzed by scanning electron microscope and FTIR, and the pyrolysis gaseous products were investigated by TG-FTIR technique. Besides, complex viscosity of PS composites composed of various chelate borates from a rheology instrument indicated that the improvements of flame retardancy of PS composites depended on the temperature of construction of crosslinked network by expandable graphite, which the chelate borates showed distinctive influence. Accordingly, the flame-retarding mechanism about fast response to flame has been proposed.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 92
·89821-89826
·
IF 3.289
Xinyu Wang,Defeng Xing,Nanqi Ren
The biocathode bioelectrochemical system (bioc-BES) was used for p-nitrophenol (PNP) degradation with sodium bicarbonate as the carbon source. The PNP degradation efficiency in bioc-BES with applied voltage of 0.5 V reached 96.1% ± 0.5% within 72 h, which was much higher than that obtained in the biocathode BES without applied voltage (bioc-BES-NAP), open circuit biocathode BES (OC-bioc-BES) or abiotic cathode BES (abioc-BES). With the increase in the PNP concentration from 20 mg L−1 to 60 mg L−1, the PNP concentration of the effluent decreased from 21.66 ± 2.94 mg L−1 to 0.38 ± 0.1 mg L−1 in 48 h. The final reductive product of PNP was p-aminophenol (PAP) in the biocathode chamber. High-throughput 454 pyrosequencing showed that predominant populations in the biocathode biofilm of bioc-BES were affiliated with electrochemically active Delftia and Diaphorobacter, while Aminobacter was the predominant population in the biocathode biofilm of the bioc-BES-NAP and OC-bioc-BES. These results suggested that microbial electrocatalysis and electrochemically active bacteria on the cathodic electrode accelerated PNP degradation in the biocathode BES (bioc-BES). The biocathode BES will be a promising treatment technology for PNP-containing wastewater.
研究领域:
环境微生物学
·
环境工程
·
生物电化学
·
污染物降解
·
废水处理
·
微生物生态学
✓ 已验证
DOI
高影响因子
TETRAHEDRON
·
2014
·Vol. 70
·期 47
·9033-9040
·
IF 2.817
Tao Liu,Meng-Meng Liu,Xiao-Wen Zheng,Chong-Yang Du,Xiang-Yang Cui,Lu Wang,Ling-Li Han,Zhang-Yu Yu
The redox reactions of p -hydroquinone and pyrocatechol undergo a two-proton-two-electron process in aqueous solution. We calculated their redox potentials at the B3LYP/6-311+G(d,p) level, and verified the values by employing cyclic voltammetry experiments. Then we selected seven substituent groups (–F, –Cl, –OH, –COOH, –CN, –NH 2 , and –NO 2 groups) to systematically investigate the substituent effect , including the sort, position, and number of the substituent, on the redox potentials of p -hydroquinone and pyrocatechol. The calculated results show that –NH 2 and –OH groups can decrease the redox potentials, while –F, –Cl, –COOH, –CN, and –NO 2 groups increase the potential values of p -hydroquinone and pyrocatechol. The calculations can accurately predict the substituent effects on the redox potentials of pyrocatechol and p -hydroquinone. We would expect that the accurate calculation results for the model systems could be applied in the prediction of electrode potentials of other molecules.
研究领域:
物理有机化学
·
电化学
·
计算化学
·
分子设计
·
生物电化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）