JOURNAL OF APPLIED POLYMER SCIENCE
·
2014
·Vol. 131
·期 19
·
IF 1.64
Huachuan Zhang,Min Li,Yuyuan Deng,Chengxi Zhang,Qichao Ran,Yi Gu
In this article, a kind of styrylpyridine-containing polybenzoxazine was obtained via the Knoevenagel reaction between benzaldehyde and methylpyridine groups. The benzoxazine monomer (MPBC) containing the benzaldehyde and methylpyridine groups was synthesized firstly and its structure was characterized by Fourier transform infrared (FTIR) spectra, 1 H NMR and 13 C NMR. With the aid of differential scanning calorimetry, FTIR, and photoluminescent tests, the interesting curing behaviors were probed. The results showed that the ring-opening polymerization occurred at lower temperature, and the Knoevenagel reaction further took place at elevated temperature. The amine and phenol moieties were bonded together to form the styrylpyridine structure. Due to these special crosslinking structures, the corresponding polybenzoxazine exhibited excellent thermal stability, and had a special high char yield of 74.5%. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131 , 40823.
研究领域:
材料科学
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高分子化学
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DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2018
·Vol. 136
·期 3
·46979
·
IF 1.901
Yuanbo Cai,Wu Yan,Xuesong Peng,Mei Liang,Lin Yu,Huawei Zou
In this work, the acrylonitrile (AN)-styrene (St)-divinylbenzene (DVB) resin was synthesized via suspension polymerization in the presence of inert porogens as diluent. The relationship of the solubility parameter (SP) of the materials and the porous properties of the resin was investigated. These porous spherical resin particles (0.25–0.84 mm) can be used as precursors of amidoxime resin which has a high metal ion chelating efficiency. The results showed that the porous properties (surface area and mean pore width) of the resin changed with variation in the compatibility between monomers and porogens. According to the the BET theory to N 2 sorption and scanning electron microscopy (SEM), the specific surface area of the obtained beads was strongly dependent on the compatibility of the components of the system and achieved values from 3.3 to 66.8 m 2 /g. The surface area of the terpolymer beads was found to rise with a decrease in the content of acrylonitrile or an increase in the SP of the porogens. However, the variation of the pore size was just the opposite. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136 , 46979.
研究领域:
高分子化学
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材料科学
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DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
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2019
·Vol. 26
·期 15
·15011-15018
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IF 2.914
Yi Xianliang,Chi Tongtong,Li Zhaochuan,Wang Jianfeng,Yu Mingyue,Wu Minghuo,Zhou Hao
The combined effect of polystyrene (PS) particles and triphenyltin chloride (TPTCl) to the green algae Chlorella pyrenoido s a was studied. The 96 h IC 50 of TPTCl to the green algae C. pyrenoidosa was 30.64 μg/L. The toxicity of PS particles to C. pyrenoidosa was size-dependent, with the 96 h IC 50 at 9.10 mg/L for 0.55 μm PS but no toxicity observed for 5.0 μm PS. The exposure to 0.55 μm PS led to damage on structure of algal cells, which could in turn cause inhibition on photosynthesis and population growth of the green algae. TPTCl concentrations in test medium were lowered by 15–19% at presence of 0.55 μm PS particles, indicating a reduced bioavailability of TPTCl. In spite of this reduced bioavailability, the presence of PS increased the toxicity of TPTCl, which might be attributed to facilitated uptake of TPTCl by the green algae after the damage of cell structure. The overall results of the present study provided important information on the effect of PS on the bioavailability and toxicity of TPTCl to phytoplankton species.
研究领域:
环境科学
·
毒理学
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DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF ENVIRONMENTAL ANALYTICAL CHEMISTRY
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2022
·
IF 2.731
Zhen Li,Lina Sun,Hui Wang
Microplastics (MPs) have a tremendous potential to sorb hydrophobic organic contaminants in the soil environment. The effects of MPs in the soil systems, however, remain largely unexplored. The objective of this study was to investigate the impact of polyethylene and polystyrene MPs on the transport of the benzo[a]anthracene (BaA) and benzo[a]pyrene (BaP) in soil matrices. In this study, we investigated the sorption process of BaA and BaP in batch sorption experiments in a laboratory and systematically evaluated the particle sizes of MPs (0.8, 50, 200, and 500 μm) and the environmental factors, such as pH, ionic strength, and humic acid (HA) concentration on adsorption behaviour. The results showed that the adsorption of PAHs onto MPs reached equilibrium within 24 h. The adsorption kinetics of PAHs onto MPs were fitted well with the pseudo-first-order kinetic model. The adsorption isotherm modelling showed a better fit of the adsorption results to the Freundlich model. The thermodynamic research indicated the adsorption of BaA and BaP as spontaneous and endothermic processes. Additionally, the adsorption capacity of BaA and BaP reached the highest when polyethylene and polystyrene MPs with a particle size of 0.8 μm and 50 μm, respectively. The sorption of BaA and BaP on PE and PS MPs was significantly influenced by pH and the peaking at pH 5.0 and 7.0, respectively. Furthermore, the adsorption mechanisms of the BaA and BaP on MPs were dominated by electrostatic interaction, π–π interactions, and hydrophobic interaction.
研究领域:
环境科学
·
土壤学
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Wenxuan Li,Peifeng Li,Feiqiang He,Xiaoping Zhang,Yuling Zhu,Jianhua Ding
In this study, a foam fractionation technique was developed for the separation and enrichment of the trace m-phenylenediamine (MPD) and o-phenylenediamine (OPD) in solution. Firstly, a self-designed foam fractionation device was assembled and built, followed by a comprehensive characterization on gas types, foam fractionation column parameters, and porous sieve plate material used in the apparatus. Subsequently, the most crucial parameters for the separation and enrichment, such as surfactant species, solution pH, electrolyte categories, and gas flow rate, were identified and optimized. The mechanisms of key processes during foam fractionation under the influence of these parameters were thoroughly discussed. Other influencing factors, such as surfactant concentration, foam collection time, and solution volume in the fractionation column, were optimized using response surface methodology (RSM). Under these optimal conditions, maximal enrichment ratios of 138.2 and 85.5 were achieved for MPD and OPD, respectively. Finally, foam fractionation coupled with high-performance liquid chromatography (HPLC) was employed to detect MPD and OPD in the solution. The results demonstrated limits of detection (LOD) of 1.5 × 10 −2 μg/L and 1.5 μg/L for MPD and OPD, with relative standard deviation (RSD) values of 4.1 % and 3.9 %. When testing various actual samples, the recoveries were in the range from 92.0 % or greater in all cases. The method exhibited advantages of high sensitivity, precision, and accuracy, attributed to the high enrichment efficiency of foam fractionation. In conclusion, the foam fractionation method established in this study offers simplicity in apparatus, operational convenience, environmental friendliness (minimized use of organic solvents), and high enrichment efficiency. It proves valuable for the quantitative analysis of trace amounts of MPD and OPD in solution, presenting a novel approach for the detection of trace organic compounds in solutions.
研究领域:
分析化学
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环境科学
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产品关联
DOI
高影响因子
ORGANIC GEOCHEMISTRY
·
2025
·
IF 2.5
Yili Mao,Ke Du,Xiaofeng Xia,Zhiwei Gao,Qilin Xiao,Quan Shi,Yongge Sun
Benzothiophenes (BTs) and dibenzothiophenes (DBTs) are an important organic sulfur compounds (OSCs) in crude oils, primarily as proxies for thermal maturity and secondary alteration, though their biological sources and depositional environments remain debated. Compound-specific stable carbon isotopic measurements could provide new insights into their origins. In this study, we employed improved methylation/demethylation reactions for selective separation of thiophenic and sulfidic compounds from crude oils to measure the stable carbon isotopic compositions of individual BTs and DBTs. Experiments with model compounds show no significant isotopic fractionation of BTs and DBTs through entire procedure, while small fractionation occurs for sulfidic compounds. Pre-removal of alkanes and additional purification by alumina column chromatography effectively reduced co-elution interference, enhancing the accuracy of isotopic measurements. To demonstrate the method’s applicability, two crude oils from Chinese petroliferous basins were analyzed, integrating δ 34 S values of individual DBTs. In the low maturity, non-biodegraded lacustrine oil, the DBTs exhibit highly 13 C-depleted values (av., −35.2 ‰) compared to oil fractions and non-sulfurized individual organic compounds. With the exception of 1-methyldibenzothiophene (−29.1 ‰), the BTs are enriched in 13 C relative to DBTs by up to ∼5.5 ‰, suggesting the distinct organic sources. In the biodegraded marine oil, although a small discrepancy in δ 13 C values (∼1 ‰) remains, similar δ 13 C values of oil components indicate a shared source, as shown by δ 13 C values of pristane (–33.0 ‰) and phytane (–33.7 ‰). δ 34 S values of individual DBTs (21–23 ‰) suggest a common source for organic sulfur given its moderate maturity (equivalent vitrinite reflectance of ∼0.9 % R equ ). While OSCs formation in oils from the Tarim Basin is attributed to the incorporation of TSR-H 2 S into labile compounds in biodegraded oils, we propose that OSCs in these oils form mainly from sulfur re-incorporation, followed by cyclization and/or aromatization into functionalized aromatic and alkyl cyclohexane compounds at the early stage of diagenesis. This leads to similar carbon and sulfur signatures in BTs and DBTs. Therefore, successful carbon isotope measurements of individual BTs and DBTs could provide new insights into their sources and formation pathways, and application limitations. Future studies on samples from diverse geological settings could further demonstrate the methods potentials.
研究领域:
地球化学
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石油地质学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2011
·
IF 2.089
Baimei Yang,Hui Wan,Guofeng Guan
Isobaric binary vapor–liquid equilibrium (VLE) data for 1-butanol + ethylbenzene, or o-, or m-, or p-xylene and isobaric quinary VLE data for 1-butanol + ethylbenzene + o-xylene + m-xylene + p-xylene are measured at 101.33 kPa using a modified Rose cell with circulation of both phases. The four binary systems of 1-butanol + ethylbenzene, or o-, or m-, or p-xylene exhibit minimum boiling azeotropes, and the composition of the azeotropes are reported. The VLE data for the four binary systems are checked to meet rigorous thermodynamic consistency by Herington method and the point-to-point test of the Fredenslund method. The nonideality in vapor phase of the measured binary systems is analyzed through calculating fugacity coefficients. Combined with the Hayden–O'Connell (HOC) equation, the VLE data for 1-butanol + ethylbenzene, or o-, or m-, or p-xylene are well-correlated by the nonrandom two-liquid (NRTL), universal quasichemical activity coefficient (UNIQUAC), and Wilson equations. The NRTL model parameters obtained from correlation are used to predict the VLE data of the quinary system. According to the average absolute deviation values, the obtained quinary predicted values are in good agreement with the experimental values.
研究领域:
化学工程
·
热力学
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产品关联
DOI
高影响因子
POLYMER
·
2017
·
IF 3.684
Ying Yan,Ningwei Sun,Xiaoteng Jia,Xincai Liu,Ce Wang,Danming Chao
Electroactive materials have gained increasing attention for their intelligent applications. In this work, we report the design and synthesis of a novel electrochromic and electrofluorochromic dual-switching polyurea bearing oligoaniline and fluorescent triphenylamine units (PUOT). Cyclic voltammogram of PUOT exhibits two reversible redox couples at 0.96 V/0.73 V and 1.36 V/1.11 V (vs. Ag/AgCl reference electrode), ascribed to the redox transformation of oligoaniline and triphenylamine groups, respectively. In this wide potential window (0–1.6 V), the PUOT film reveals a unique multistage regulated electrochromic behavior with maximal transmittance contrast value of 38% switching from 0.0 V to 1.0 V, and partial transmittance contrast value of 14% (0–1.6 V) and 24% (1.0–1.6 V). Furthermore, its electrofluorochromic behavior has also been disclosed at the potential range of 0–1.0 V, which demonstrates that the oligoaniline groups should be served as electroactive units in this electrofluorochromic system. Our research not only presents a deep understanding of the optical-electrical modulation mechanism but also paves the way for their future applications.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2019
·
IF 6.393
Chunsong Lu,Jie Liu,Lanlan Gan,Xiaoming Yang
Distinguishing the isomers is considered to be challenging, and shows the great importance in the biochemical and pharmaceutical fields. Herein, the blue carbon dots (CDs) were successfully raised on the basis of a facile hydrothermal way, since Cryptococcus served as the carbon source. Importantly, the as-prepared CDs were employed to achieve the differentiation and detection of two benzenediols. To be specific, the fluorescence of CDs was enhanced once m -benzenediol (resorcinol) was added, while introducing p -benzenediol (hydroquinone) lead to their fluorescence quenching. Towards the mechanism, the addition of m -benzenediol promoted the formation of hydrogen bonds between m -benzenediol and CDs, and thus resulting in their enhanced fluorescence. In contrast, the fluorescence quenching occurred due to the electron transferring from the rich-electrons of CDs to p -benzoquinone, when p -benzenediol was oxidized to be p -benzoquinone. Therefore, a differentiating strategy of two isomers has been proposed, and also contributed to detecting m -benzenediol and p -benzenediol concentrations in the ranges of 2 × 10 −3 to 1 × 10 −7 M and 2 × 10 -5 to 2 × 10 -9 M, respectively. Although there already existed the high performance liquid chromatography and other chemical methods for determining benzenediols, the current strategy provided a new way of distinguishing and assaying the isomers of benzenediols.
研究领域:
化学
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材料科学
·
分析化学
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产品关联
DOI
高影响因子
CHEMICAL PAPERS
·
2017
·Vol. 71
·期 10
·1985-1992
·
IF 1.258
Fan Haiyang,Chen Lifeng,Sun Huihui,Wang Hualei,Liu Qinghai,Ren Yuhong,Wei Dongzhi
This study aimed at developing an efficient biotransformation process for phenylacetic acid production from phenylacetonitrile by using recombinant Escherichia coli M15 harboring a double mutant MG nitrilase (I113M/Y199G) from Burkholderia cenocepacia J2315. A yield of 2310 U/mL nitrilase was obtained by fermentation after the optimization of cultivation conditions, with a specific activity of 64 U/mg dcw. The MG nitrilase showed high substrate tolerance and completely hydrolyzed 100 mM phenylacetonitrile in 30 min under optimal conditions. To alleviate substrate inhibition, periodic or continuous batch-feeding of substrate was used during the biotransformation. Up to 164 g/L substrate was completely hydrolyzed in 9 h with continuous batch-feeding using resting cells, corresponding to 400 U/mL of nitrilase activity, and leading to production of 163.4 g/L phenylacetic acid. The hydrolysis process has potential application for phenylacetic acid production on a large scale.
研究领域:
生物化学
·
生物工程
·
酶学
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产品关联
DOI
高影响因子
Scientific Reports
·
2016
·Vol. 6
·期 1
·1-9
·
IF 5.228
Peng Fang,Wang Qi,Shi Rongjia,Wang Zeyi,You Xin,Liu Yuhong,Wang Fenghe,Gao Jay,Mao Chun
A novel and efficient catalyst is one of the goals in the material field, and the involvement of nanoscience and technology has brought new vigor to the development of catalyst. This research aimed to develop a simple two-step route to fabricate Fe 3 O 4 @PS/PDA-Ag hybridnanotubes with size-controllable and highly dispersed silver nanoparticles (NPs). First, Fe 3 O 4 @PS nanotubes of a sound mechanical property were prepared using polystyrene (PS)/toluene solution containing highly dispersed oleic acid modified Fe 3 O 4 particles in a commercial AAO template. Next, the facile technique was used to form in situ silver NPs on the surface of magnetic PS (Fe 3 O 4 @PS) nanotubes through dopamine coating. The catalytic effects of the prepared Fe 3 O 4 @PS/PDA-Ag hybridnanotubes with highly dispersed AgNPs were characterized using a range of analytical methods, including transmission electron microscopy, thermogravimetric analysis, UV-Visible spectroscopy, and X-ray diffraction. It was found that such prepared Fe 3 O 4 @PS/PDA-Ag hybridnanotubes had a large specific surface area. They possessed excellent activities in catalyzing the reduction of 4-nitrophenol (4-NP) by NaBH 4 in the aqueous phase. Furthermore, they were readily separated from fluid and retrieved by an external magnet. Their catalyst activity and recyclability demonstrated that this approach we proposed had the potential to become a new idea and route for catalytic platform.
研究领域:
材料科学
·
纳米技术
·
催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COMBUSTION AND FLAME
·
2016
·
IF 4.168
Wenhao Yuan,Yuyang Li,Gaëlle Pengloan,Casmir Togbé,Philippe Dagaut,Fei Qi
The flow reactor pyrolysis and jet-stirred reactor (JSR) oxidation of ethylbenzene are investigated in this work. The flow reactor pyrolysis is studied at pressures of 0.04, 0.2, and 1.0 atm and temperatures from 850 to 1500 K using synchrotron vacuum ultraviolet photoionization mass spectrometry . The jet-stirred reactor oxidation is studied at 1 atm with three equivalence ratios ( ϕ = 0.5, 1.0, and 1.5) and at 10 atm with the equivalence ratio of 1.0, using gas chromatography and Fourier transform infrared spectroscopy for mole fractions measurements. A detailed kinetic model of ethylbenzene pyrolysis and oxidation is developed by extending our recently reported oxidation models for toluene and styrene , and is validated on the new experimental data reported here. The benzyl radical and styrene are demonstrated to be the most important intermediates in both the pyrolysis and oxidation of ethylbenzene. For the JSR oxidation of ethylbenzene, the low temperature chemistry is found to play a significant role at 10 atm. The present model is also validated on the experimental data from the literature, including the species concentration profiles and global combustion parameters such as ignition delay times and laminar flame speeds. The good performance of the model for reproducing these data reveals its ability to predict ethylbenzene combustion over a wide range of conditions.
研究领域:
化学工程
·
燃烧科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）