JOURNAL OF HAZARDOUS MATERIALS
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2020
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IF 9.038
Xiaojun Zhou,Lingshuai Kong,Zongyu Jing,Shuqing Wang,Yongchao Lai,Meng Xie,Long Ma,Zhenyu Feng,Jinhua Zhan
In this study, superparamagnetic β-CD-MnFe 2 O 4 with a large surface area was synthesized via a facile co-precipitation method, with β-cyclodextrin (β-CD) acting as a coating agent. The as-prepared β-CD-MnFe 2 O 4 exhibited better catalytic performance than bare MnFe 2 O 4 in terms of activating peroxymonosulfate (PMS) to degrade 2,4-dichlorophenol (2,4-DCP) over a broad pH range of 5–11. Electron spin resonance spectroscopy (ESR) and free radical quenching experiments indicate that various active species (SO 4 − / OH/O 2 − / 1 O 2 ) are generated in the β-CD-MnFe 2 O 4 /PMS system and that pollutants trapped in the cyclodextrin cavity are quickly degraded. Various reaction parameters of the β-CD-MnFe 2 O 4 /PMS system and the stability of β-CD-MnFe 2 O 4 were also investigated. The results indicate that β-CD-MnFe 2 O 4 is promising for use in water purification owing to its excellent magnetic separation and recovery properties and good resistance to humic acid (HA).
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高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2020
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IF 4.939
Xinming Du,Hongyu Zhang,Yongjiang Yuan,Zhe Wang,Jingmei Xu
High ionic conductivity and excellent alkaline stability are very important for solid electrolyte . Therefore, spindle-shaped anion exchange membranes (AEMs) based on poly (arylene ether ketone) and 1-Bromo-N,N,N-trimethylhexane-6-aminium bromide (Br-QA) have been prepared. The obtained Br-QA can be grafted with poly (arylene ether ketone) main chains to form micro-phase separation structure enhancing the ionic conductivity . Especially, the grafting quaternary ammonium (QA) cation groups are separated by alkyl bromine endows the AEMs with alkaline stability features. Simultaneously, the OH − conductivity of the QA-PAEK-0.6 obtained membranes is 0.046 S/cm under fully hydrated conditions at 60 °C. After immersing into 1 M NaOH alkaline solution for 15 days at 60 °C, the anionic conductivity still high to 0.03 S/cm. Meanwhile, the poly (arylene ether ketone) backbones provide excellent mechanical properties and the Br-QA cation groups also possess good thermal stability , which satisfy the requirement of wide applications.
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NEW JOURNAL OF CHEMISTRY
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2020
·Vol. 44
·期 4
·1485-1492
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IF 3.288
Shuo Li,Huizhong Si,Jianshu Li,Mengtian Jia,Xiaohong Hou
In this study, a metal organic framework/chitosan/polyethylene oxide foam (MOFs/CS/PEO foam) was successfully designed and fabricated, in which polyethylene oxide (PEO) acted as a porogen to increase the adsorption capacity of the MIL-53(Al)/CS foam. The inherent characters, e.g. strength and stability, of the modified foam were also significantly improved. As MIL-53(Al) exhibits the highest adsorption capacity in both computations and experiments among the candidates such as MIL-53(Al), MIL-53(Fe), MIL-101(Cr), MIL-101(Fe), UiO-66(Zr), and MIL-100(Fe), the MIL-53(Al)/CS/PEO foam was chosen as a sorbent to develop a vortex assisted solid phase extraction method for the first time. The efficient method was then successfully applied for the extraction of a trace amount of five bisphenols (bisphenol A, bisphenol B, bisphenol C, bisphenol AF and bisphenol F) in beverages and water with plastic containers, followed by high-performance liquid chromatography-fluorescence detection. A satisfactory result of methodology validation was obtained. Under the optimum conditions, the linear ranges were 0.1–20 μg L−1 with the correlation coefficient (r2) ranging from 0.9943 to 0.9977. The method detection limits were in the range of 0.019–0.065 μg L−1. And the recoveries ranged from 72.68 to 104.6% with relative standard deviations smaller than 9.1%. The proposed hybridization foam was durable and environmentally friendly, since it still maintained adsorption ability after being recycled ten times. The novel method proposed in this work could provide technical support in the fields of environmental protection and food safety.
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JOURNAL OF MEMBRANE SCIENCE
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2020
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IF 7.183
Junbin Liao,Xinyan Yu,Quan Chen,Xing Gao,Huimin Ruan,Jiangnan Shen,Congjie Gao
Ion-conductive polymers having highly ordered and well-defined phase-separated structures are potential materials for use as monovalent anion-selective membranes (MASMs). In this work, to investigate the effect of hydrophobic spacers, four side-chain-type imidazolium salt-tethered poly(arylene ether sulfone) anion-exchange membranes (AEMs) with different alkyl spacer lengths (–CH 2 – number: 3, 6, 9, and 12) were fabricated for use in electrodialysis (ED). Our investigations using atomic force microscopy , small angle X-ray scattering and X-ray diffraction demonstrate that the extended alkyl spacers change the nano-phase-separated structures, with an increased ion cluster space ranging from 3.29 nm to 7.76 nm, resulting from increased immiscibility between the additional hydrophobic alkyl spacers and (i) the hydrophobic aromatic backbones and (ii) the hydrophilic ion-conductive groups. In addition, with the extension of the alkyl spacer, chloride (Cl − ) ion conductivity at 25 °C decreases from 16.4 mS cm −1 to 11.4 mS cm −1 and water uptake is reduced to 12.8% (20 °C). It is found that the as-prepared AEM with a hexyl alkyl spacer shows the superior perm-selectivity (Cl − /SO 4 2− ) of 7.10 (separation efficiency: 70.3%), as compared with three others (3.48, 6.81, and 4.26). This work thus presents an efficient strategy to guide the architectural design of novel MASMs.
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INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2020
·
IF 4.939
Xinming Du,Zhe Wang,Hongyu Zhang,Wenchang Liu,Jingmei Xu
In order to improve the performance of anion exchange membrane (AEMs) as the core component of alkaline fuel cell , a novel pentamethyl-contained phenolphthalein multi-arm monomer is synthesized. The highly imidazolium-functionalized poly (arylene ether ketone) membrane (Im-PEK-x) are prepared by introducing 1,2-dimethylimidazole as hydrophilic segments. The monomer, polymer and anion exchange membranes are confirmed by 1 H NMR spectra. The well-defined micro-phase separated structure of membranes is conducive to ion transport and the structure is investigated by TEM and SAXS. The imidazolium-functionalized membranes (Im-PEK-0.8) exhibits high ionic conductivity (0.148 S/cm at 80 °C). The tensile strength of Im-PEK-0.8 membrane is 30.06 MPa. Furthermore, after immersing in 60 °C, 2 M NaOH solution for 240 h, the ionic conductivity remains 0.092 S/cm for Im-PEK-0.8. The 1,2-dimethylimidazole enhance alkaline stability by steric effect of the substituent group at the C2 position. All these results indicate that this is a new method to enhance conductivity and stability performance of AEMs.
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JOURNAL OF MEMBRANE SCIENCE
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2020
·
IF 7.183
Bin Shen,Balakondareddy Sana,Hongting Pu
To meet highly conductive and chemical stable anion exchange membranes (AEMs), a series of multi-block poly(ether sulfone)s with long side chains densely terminated by piperidinium (bPES-Pip-X-Y) are synthesized. The multi-block structure and the aggregation of ionic groups on the flexible side chains are responsible for the distinct hydrophilic/hydrophobic microphase separation , which can be observed via transmission electron microscopy (TEM). The resulted membranes achieve the high conductivity (in-plane) of 48.5–105.4 mS cm −1 at 80 °C. Moreover, the AEMs prepared exhibit good alkaline stability due to the presence of cation-terminated long side chain structure. The bPES-Pip-10-5 membrane still maintains 88% of the original conductivity after treated in 1 M KOH solution at 60 °C for 336 h. The membrane electrode assembly based on bPES-Pip-10-5 with a power density of 136.9 mW cm −2 at a current density of 292.5 mA cm −2 is obtained.
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MICROCHIMICA ACTA
·
2020
·Vol. 187
·期 7
·1-11
·
IF 6.232
Sun Qianqian,Gao Chaohong,Ma Wende,He Yanting,Wu Jie,Luo Kailong,Ouyang Dan,Lin Zian,Cai Zongwei
Core-shell structured magnetic covalent organic framework (Fe 3 O 4 @COF) nanospheres were rapidly synthesized at room temperature using the monodisperse Fe 3 O 4 nanoparticles (NPs) as magnetic core and benzene-1,3,5-tricarbaldehyde (BTA) and 3,3′-dihydroxybenzidine (DHBD) as two building blocks (denoted as Fe 3 O 4 @BTA-DHBD), respectively. They can serve as a mass spectrometry probe for rapid and high-throughput screening of bisphenols (BPs) from pharmaceuticals and personal care products (PPCPs) by surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS). The Fe 3 O 4 @BTA-DHBD nanospheres showed some superior features involving average pore size distribution (2.82 nm), high magnetization values (42.5 emu g −1 ), high specific surface area (82.96 m 2 g −1 ), and good chemical/thermal stability. It was used as both ideal adsorbent for enrichment of BPs and new substrate to assist ionization in SELDI-TOF-MS. The method exhibited good linearity in the range 0.05–4000 ng mL −1 with correlation coefficients ( r ) higher than 0.9920. Low limits of detection (LODs) (500 pg mL −1 for bisphenol A (BPA), 2 pg mL −1 for bisphenol B (BPB), 28 pg mL −1 for bisphenol C (BPC), 60 pg mL −1 for bisphenol F (BPF), 33 pg mL −1 for bisphenol AF (BPAF), 200 pg mL −1 for bisphenol BP (BPBP), 10 pg mL −1 for bisphenol S (BPS), 90 pg mL −1 for tetrabromobisphenol A (BPA(Br) 4 ), and 380 pg mL −1 for tetrabromobisphenol S (BPS(Br) 4 )) and good recoveries (80.6–115%) of BPs in PPCPs were achieved. The relative standard deviations (RSDs) of spot-to-spot ( n = 10) and sample-to-sample ( n = 5) were in the ranges 5–11% and 5–12%, respectively. The dual-function platform was successfully applied to the quantitative determination of BPs in PPCPs. It not only expanded the scope of the application of COFs but also provided an alternative strategy for the determination of hazardous compounds in PPCPs.
Schematic representation of the synthesis of core-shell structured magnetic covalent organic framework nanospheres (Fe 3 O 4 @COFs) and its application in the analysis of bisphenols by using Fe 3 O 4 @BTA-DHBD nanospheres as a MS probe based on surface-enhanced laser desorption/ionization time-of-flight mass spectrometry.
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INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2020
·
IF 3.573
Yuan Liu,Yunyan Peng,Jun Luo,Jingkai Liu,Xiaoqing Liu
A bridging group is an indispensable element for the preparation of diphenol-based benzoxazines, and inevitably, its electronic features will affect the H-bond formation of obtained benzoxazine, which is a crucial factor that not only makes a difference on curing behaviors of benzoxazine but also poses significant influence on the performances of cured resins. However, systematical investigation about the effects of the bridging group on the H bonds in benzoxazine is still in a barren state. Herein, we bridge the gap with three high-purity model benzoxazine monomers. The results showed that electron-donating bridge groups made the benzoxazine monomers tend to start the curing reaction earlier, whereas the electron-withdrawing bridging groups had the opposite effect. In addition, it was also confirmed that the H bonds in polybenzoxazine could be readily tailored by carefully selecting the bridge groups of aromatic diphenols. In this work, some basic characteristics about benzoxazine have been revealed, which are helpful for us to understand its structure–properties relationship more deeply.
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CHEMICAL ENGINEERING JOURNAL
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2020
·
IF 10.652
Qun Wang,Han Zeng,Youheng Liang,Ye Cao,Yang Xiao,Jun Ma
The heterogeneous catalyst Mackinawite (FeS) was applied to activate periodate (IO 4 − ) to degrade endocrine disruptors bisphenol AF (BPAF). This study investigated the influence of FeS dosage, periodate dosage, BPAF concentration, initial pH value and inorganic ions on BPAF degradation by FeS/IO 4 − system. The results showed that the BPAF was effectively degraded by FeS/IO 4 − system. The acidic pH exhibited higher efficiency in BPAF degradation compared with alkaline and neutral conditions. Furthermore, the BPAF degradation was dramatically promoted in the presence of Cl − and SO 4 2− , whereas CO 3 2− inhibited BPAF degradation. The radical scavenging tests and EPR indicated that singlet oxygen ( 1 O 2 ), superoxide radicals (O 2 − ) and SO 4 − were committed to the degradation of BPAF, among which O 2 − , 1 O 2 were predominant radicals. The separate experiments showed that Fe(Ⅱ) participated in the activation of periodate. Furthermore, the effects of sulfur species (including the S 2− , SO 3 2− ) on BPAF degradation by FeS/IO 4 − system were studied. The radical quenching tests suggested that S 2− and SO 3 2− were responsible for producing SO 4 − . The findings of this study elucidated an approach for the removal of micro-pollutants in the water environment through heterogeneous activation of periodate by FeS.
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CHINESE JOURNAL OF POLYMER SCIENCE
·
2020
·Vol. 38
·期 9
·983-992
·
IF 3.154
Yang Guang-Yao,Tong Li-Fen,Liu Xiao-Bo
Multi-walled carbon nanotubes (MWCNTs) modified with silane coupling agent A-1120 (MWCNTs-A1120) were prepared. Compared with the raw MWCNTs, acidified MWCNTs (MWCNTs-COOH), and MWCNTs grafted with EDA (MWCNTs-NH 2 ), MWCNTs-A1120 have the best dispersion in fluoroelastomer at the same doping ratio. Therefore, fluoroelastomer/MWCNTs-A1120 composite has the best mechanical properties with tensile strength of 13.92 MPa and elongation at break of 111.78%. Then, the effects of doping amount of MWCNTs-A1120 on the electrical properties of the composites were investigated. The dielectric constant of the composite increases with the increase of MWCNTs-A1120, and the dielectric loss does not change much at the low doping amount such as 0.5 wt%. When the doping amount of MWCNTs-A1120 is 5 wt%, the dielectric constant and the dielectric loss value are greatly increased, and the volume resistivity is greatly decreased, which proves that the conductive network is formed in the composite, so the filling amount of 5 wt% is the percolation threshold. The tensile deformation of the sample also affects the electrical properties of the composites. As the tensile deformation increases, the dielectric constant and dielectric loss of the composite decrease. For the composite with 5 wt% MWCNTs-A1120, excessive tensile deformation will destroy the conductive network structure of the composite, so the composite will change from conductive material to dielectric material. Therefore, such composite is a good candidate for flexible conductive material or flexible dielectric material used in harsh environments such as high temperatures and various aggressive solvents.
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JOURNAL OF POLYMER RESEARCH
·
2019
·Vol. 26
·期 12
·1-8
·
IF 1.53
Chen Zhaoyu,Wang Zhe,Hou Lei,Wang Chunmei,Du Xinming,Liu Chang,Liu Wenchang,Li Haiqiang,Xu Jingmei
Poly (arylene ether ketone) containing different content of the amino groups (Am-PAEK) polymer membranes were prepared by nucleophilic polycondensation used as gas separation membranes. Am-PAEK was synthesized successfully confirmed by Fourier Transform Infrared (FT-IR). The glass transition temperature (T g ) of Am-PAEK membranes enhanced from 164.83 °C to 192.83 °C, and the XRD results showed that the crystallinity of the Am-PAEK membranes increased as the amino groups content increased. The tensile strength and young’s modulus of the Am-PAEK-10% achieved 44.10 MPa and 2053 MPa, respectively. All of the Am-PAEK membranes exhibited excellent thermal performance. The gas separation capability testing showed that the Am-PAEK-10% membrane showed higher pure gas permeability [P(CO 2 ) = 12.38] as well as ideal permselectivity [α(CO 2 /CH 4 ) = 21.34], the separation performance was closest the Robeson upper bound. It was due to that acid–base and hydrogen bond interactions between the amino groups and carbon dioxide exit in the membranes. Thus, the strategy of precise regulated the content of amino groups of Am-PAEK showed a prospective approach for high performance gas separation membranes.
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高影响因子
POLYMER
·
2019
·
IF 3.771
Shuxiang Ding,Chunxue Wang,Zuosen Shi,Xiaoyu Shi,Zhenzhen Cai,Changming Chen,Zhanchen Cui
A series of fluorinated polycarbonates (AF-3OH-PC MAs) terminated by different proportions of acrylate group were synthesized and directly used as photoresist materials. The materials can directly form a cross-linked film under UV light and initiator conditions without the addition of small molecular crosslinkers. The thermal stability (Td up to 416 °C), the absorption at 1550 nm is almost zero and electro-optical stabilities (after 80 °C for 200 h, the r 33 remains 91% of the initial value) are significantly improved since the small molecular crosslinkers were not added. The propagation and insertion loss of the device were measured by a cut-back method to be only 0.66 dB/cm and 1 dB, respectively. It may be possible to have an enlightening effect on preparing electro-optical switches with better performance.
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危险品化学品经营许可证（带存储）