HIGH PERFORMANCE POLYMERS
·
2023
·
IF 2.1
Slimane Abdous,Mehdi Derradji,Oussama Mehelli,Karim Khiari,Mohamed Elamine Kadi,Abdelmalek Habes,Noureddine Ramdani,Abdeljalil Zegaoui,Wenbin Liu
The design of lightweight neutron shields has been restricted for quite some time to the use of epoxy thermosets as the main building blocks. Meanwhile, the recent developments in the field of polymers suggest otherwise. Indeed, the phthalonitrile (PN) resins have taken the lead over traditional thermosets in many demanding applications. Therefore, in a vision to introduce newer matrices with better performances and to further expand the applications of the PN resins into the nuclear field, the neutron shielding efficiency along with the thermal resistance performances of the neat PN polymer and its subsequent silane surface-modified B4C-reinforced composites were investigated. The neutron shielding measurements were performed using an optimized experimental setup at the NUR research reactor in Algiers. The neat PN polymer displayed better thermal neutron screening performances than the epoxy and benzoxazine, with a macroscopic cross-section (Σ) of a 1.936 cm−1, equivalent to a mean free path (λ) of 0.358 cm. The effect of the particle amount was also studied to maximize the shielding ability of the developed materials. For instance, the PN composite containing 20 wt. % of B4C displayed an outstanding screening ratio of about 99.8% for a sample thickness of 13 mm. Finally, the remarkable findings were put into context by providing multifaceted comparisons with the available shielding materials.
研究领域:
材料科学
·
核工程
✓ 已验证
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
·
2019
·
IF 3.621
Meisheng Li,Jie Wang,Shouyong Zhou,Ailian Xue,Feiyue Wu,Yijiang Zhao
Highly water-selective poly(vinyl alcohol) (PVA)/polyacrylonitrile (PAN) pervaporation membranes were prepared by combining self-aggregation crosslinking reactions for PVA through ammonium persulfate (APS) initiations and interface physicochemical structure regulations for PAN supports. The membrane physicochemical properties were tested and the pervaporation performances were investigated by separation of 95 wt% ethanol aqueous. The results showed that the swelling degree and crystalline region of PVA membranes decreased with the increasing of APS content. On the contrary, the gel fraction of PVA membranes increased. Interestingly, the interface physicochemical structure between the PAN support and PVA separation layer played an important role in pervaporation processes. When the PAN supports were treated by sodium hydroxide (NaOH) and tannic acid (Ta), the water fraction in permeation always kept over 99.99 wt%, especially after Ta treatment. After optimization, the membrane based on PVA content of 8 g, 1.25 g self-crosslinking agent of APS and spin-coated onto H 2 -PAN (PAN modified by NaOH and Ta respectively), showed good permeability-selectivity and long-term performance stabilities. The total flux and water content ratio in permeation were 117.6 g/(m 2 h) and 99.99 wt% respectively by using the PVA 8-1.25 /H 2 -PAN membrane. After running for 120 h, the membranes still displayed a good stability for the ethanol dehydration in the pervaporation process. Importantly, the ethanol solution could be concentrated to over 99.99% using this polyacrylonitrile-based self-aggregation crosslinked poly (vinyl alcohol) pervaporation dehydration membrane.
研究领域:
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
Nanomaterials
·
2018
·Vol. 8
·期 7
·499
·
IF 3.504
Guangyang Liu,Ruonan Zhang,Lingyun Li,Xiaodong Huang,Tengfei Li,Meng Lu,Donghui Xu,Jing Wang
Monitoring of low levels of chlorsulfuron in environmental water samples is important. Although several detection methods have been developed, they all have some drawbacks, such as being time-consuming, requiring expensive instruments and experienced operators, and consuming large volumes of organic solvents. There is an urgent need for a simple, rapid, and inexpensive detection method for chlorsulfuron. Herein, such a method was developed using anti-aggregation of gold nanoparticles (AuNPs) in the presence of acetamiprid in agricultural irrigation water samples. Aggregation of the AuNPs was induced by acetamiprid, and this produced a distinct color change from Bordeaux red to blue. However, the strong hydrogen bonding interaction between chlorsulfuron and acetamiprid could inhibit AuNP aggregation. The effect of chlorsulfuron on the anti-agglomeration behavior of AuNPs was monitored by ultraviolet–visiblespectroscopy (UV-Vis) and the naked eye over a concentration range 0.1–100 mg/L. The detection limit for chlorsulfuron was 0.025 mg/L (signal-to-noise ratio of three). This colorimetric method was successfully applied to the determination of chlorsulfuron in spiked tap water and agricultural irrigation water with satisfactory recoveries (76.3%–94.2%).
研究领域:
环境科学
·
分析化学
✓ 已验证
DOI
高影响因子
FOOD CHEMISTRY
·
2020
·
IF 6.306
Yiwei Xu,Wen Zhang,Jiyong Shi,Zhihua Li,Xiaowei Huang,Xiaobo Zou,Weilong Tan,Xinai Zhang,Xuetao Hu,Xin Wang,Chao Liu
A novel electrochemical aptasensor modified with highly porous gold and aptamer was prepared for the determination of acetamiprid in fruits and vegetables. Highly porous gold was synthesized by electroreduction at −4 V in an electrolyte containing 2.5 mol/L NH 4 Cl and 10 mmol/L HAuCl 4 . Acetamiprid-binding aptamer was immobilized on highly porous gold by self-assembly. Acetamiprid could be captured by aptamer on the sensing interface, resulting in an increment of electron transfer resistance. Thanks to the large specific surface area of highly porous gold and the high affinity of aptamer, the aptasensor exhibited a highly sensitive impedance response for acetamiprid. Under optimal condition, the aptasensor displayed a linear response for acetamiprid in the concentration range of 0.5–300 nmol/L, and the detection limit was 0.34 nmol/L. Furthermore, the aptasensor showed high selectivity, good reproducibility and stability. Finally, the aptasensor was applied for the determination of acetamiprid in fruits and vegetables with satisfactory results.
研究领域:
分析化学
·
食品科学
✓ 已验证
DOI
PubMed
高影响因子
RENEWABLE ENERGY
·
2022
·
IF 8.634
Rulu Huang,Huai Liu,Junhua Zhang,Yuan Cheng,Liang He,Lincai Peng
Design catalytic materials with high Lewis acid/base sites for catalytic transfer hydrogenation (CTH) of levulinic acid (LvA) to γ-valerolactone (GVL) is highly demanded but challenging. Herein, we report a concept of metal ion-polymer hybridization to design a tea polyphenol (TP) and HfCl 4 co-doped polyacrylonitrile (PAN) nanofiber (Hf@PAN-TP) via electrospinning technique . Comprehensive characterization revealed the well coordination between hafnium ions and phenolic hydroxyl groups of TP on PAN fiber, which promoted the formation of Lewis acid and Lewis base sites. As expected, a satisfactory GVL yield of 99.1% with 100% of LvA conversion was obtained using isopropanol as a hydrogen donor at 170 °C in 5 h, and the catalytic activity remained unchanged for five cycles. The kinetic study revealed the lower activation energy for CTH of LvA to GVL (33.5 kJ/mol), demonstrating the outstanding GVL formation rate of 3383.9 μmol/g . h. Based on the systematical combine of catalyst characterization and catalytic behavior, the structure-function relationship and reaction mechanism were proposed. More gratifyingly, Hf@PAN-TP was applicable for catalytic reduction of various carbonyl compounds, demonstrating a great potential for upgrading biomass-derived aldehydes/ketones.
研究领域:
材料科学
·
催化化学
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2023
·
IF 7.7
Ao Sun,Yingqing Zhan,Ximin Chen,Hongshan Jia,Fei Zhu,Chunxia Zhao,Yinlong Li,Hui He,Yuanpeng Wu,Tian He,Tingting Hu
Membrane separation technique offers unique advantages for treating the emulsified oily wastewater with the oil droplet diameter less than 20 µm. However, the complicated membrane fouling originating from oils and soluble matters pose the huge challenges to membrane separation technique, which has stimulated the development of advanced membrane materials. Herein, we reported the photocatalytic and super-wetting poly (arylene ether nitrile) (PEN) fibrous composite membrane with high permeability and enhanced anti-fouling ability. The nitrogen-doped Bi 2 O 2 CO 3 (N-Bi 2 O 2 CO 3 ) was prepared by low-temperature chemical modification method and modified by dopamine (DA)-polyethyleneimine (PEI), which was further self-assembled on porous PEN support backbone. The hydrophilicity provided by the cross-linking reaction between PDA and PEI and micro-/nano- rough surface constructed by the flower-like N-Bi 2 O 2 CO 3 contributed to the super wetting properties (WCA=0°, UOCA>150°), which imparted the membrane with ultra-low oil adhesion. In particular, the arrangement of flower-like N-Bi 2 O 2 CO 3 effectively regulated the water channel of membrane, further increasing the permeate flux. Therefore, the fibrous composite membranes showed superior separation flux (632.79–762.81 L·m −2 ·h −1 ) and separation efficiency (>99.16%) for various oil-in-water emulsions, even under harsh conditions (90 ℃ and 2 M NaCl solution). More importantly, the N-Bi 2 O 2 CO 3 rendered the membrane excellent degradation rates for various dyes (MO: 95.53%, MeB : 96.40%, CV: 96.45%, CR: 87.14%), achieving favorable photocatalytic self-cleaning ability. This work opens an alternative strategy to fabricate fibrous composite membrane with synergistically enhanced anti-fouling for the treating complicated emulsified oily wastewater in petrochemical industry .
研究领域:
材料科学
·
环境工程
·
化学工程
✓ 已验证
DOI
高影响因子
Nano Research
·
2020
·Vol. 13
·期 8
·2079-2084
·
IF 8.183
Wang Hong-Hui,Lv Li-Bing,Zhang Shi-Nan,Su Hui,Zhai Guang-Yao,Lei Wei-Wei,Li Xin-Hao,Chen Jie-Sheng
The rational design of highly active and stable atomically dispersed M-X 4 (M = Fe, Co, Ni, etc., X = C, N) -based catalysts holds promises for wide application in almost all realms of catalysis. Despite great effort in the construction of specific M-X 4 centers, the possible effect of non-coordinated heteroatoms on the catalytic activity of metal centers has been rarely explored. Herein, we develop a new type of M-X 4 catalyst composed of Fe-N 4 centers and non-coordinated B heteroatoms (FeNC+B) and find the key role of non-coordinated B adjacent to Fe-N 4 centers in tailoring their electron density and final catalytic selectivity. The experimental and theoretical results demonstrated that non-coordinated boron atoms could decrease the electron density of Fe-N 4 centers to a suitable level and thus boost the selective production of nitriles from amine oxidation by depressing the formation of imines due to the flattened energy barrier of the reversible conversion of imines back to amines. As a reusable heterocatalyst, the state-of-the-art FeNC+B catalyst provides a turn-over frequency (TOF) value of 21.6 mol benzonitrile ·mol Fe −1 ·h −1 (100 °C), outpacing that of bench-marked nonnoble-metal-based homogeneous catalyst by a factor of 3.4.
研究领域:
催化化学
·
材料科学
·
理论化学
✓ 已验证
DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2020
·
IF 4.049
Mengyuan Li,Chunliu Yang,Hongyuan Yan,Yehong Han,Dandan Han
A rapid and economic integrated solid-phase extraction (ISPE) method with ionic liquid-thiol-graphene oxide composite (IL-TGO) as a new adsorbent was established for the extraction of fipronil in chicken eggs. In this study, ISPE, a new form of solid-phase extraction, which combined the advantages of pipette-tip solid phase extraction (PT-SPE) and dispersive solid-phase extraction (DSPE), achieving rapid extraction of analyte with only a small amount of adsorbent. The three-dimensional porous IL-TGO was a new ideal adsorbent for fipronil due to the multiple adsorption interactions (π-π interaction, hydrophobic interaction and hydrogen bond), large adsorption capacity and fast adsorption rate. For this ISPE procedure, the analyte was adsorbed by IL-TGO through the pipette tip mode and then eluted through dispersive mode. Under the optimized condition, the proposed method performed following merits: good linearity (r = 0.9999), precision (RSD ≤ 6.3%), high recoveries (83.7% to 97.7%), rapid extraction (16 min), low consumption of adsorbent (3.00 mg of IL-TGO). The excellent recyclability of the ISPE device and the reusability of IL-TGO were observed and high recovery of fipronil (> 90%) was obtained after fifteen cycles. This work might provide promising strategy for the sensitive extraction and analysis of trace levels of fipronil from egg products.
研究领域:
分析化学
·
食品安全
✓ 已验证
DOI
高影响因子
Journal of Inorganic and Organometallic Polymers and Materials
·
2019
·Vol. 30
·期 3
·976-985
·
IF 1.637
Zou Jiaming,Liao Kaifa,Xiang Li,Liu Mouwu,Xie Fan,Liu Xinlin,Yu Jianglai,An Xiaonan,Wang Yanfei
Poly (cyclotriphosphazene-co-4,4′-diaminodiphenyl sulfone) (PZD) microspheres were prepared by precipitation polymerization with simple scheme and convenient operation, and used as a special effect adsorbent for adsorbing cationic dye, which is methylene blue (MB) in water. The synthesized PZD microspheres were characterized by SEM, TEM and XPS techniques. The influences of temperature, adsorption time, pH initial MB solution concentration and adsorbent dosage on MB adsorption were studied. The experimental results show that the adsorption of MB dye by PZD microspheres is more in line with the pseudo-second-order kinetics model than the pseudo-first-order kinetic model. In addition, the adsorption process was further resolved using Weber’s intraparticle diffusion model. Thermodynamic experiments show that the adsorption process is spontaneously carried out by endotherm. The mechanism of adsorption of MB dye by PZD microspheres may be related to the existence of a lot of electron-rich atoms N, P, S in the adsorbent, the electrostatic attraction and π–π stacking effect between PZD microspheres and MB dye.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
Journal of Inorganic and Organometallic Polymers and Materials
·
2024
·Vol. 34
·期 6
·2501-2509
·
IF 3.9
Lin Jing,Feng Mengna
Ceramic/polymer dielectrics with excellent thermal stability and high dielectric performance exhibit great potential in advanced capacitor applications. It is still a major challenge for ceramic/polymer dielectrics to obtain high dielectric constant at low content while maintaining excellent flexibility. To alleviate this issue, here, a flexible polymer dielectric composite consisting of poly(arylene ether nitrile) (PEN) matrix and barium titanate filler coated by Carbon and polypyrone (h-BT@C@PPy) was put forward in this work. The as-prepared composite films displayed high dielectric constant, comparable low loss and favorable interfacial binding due to the hydrogen-bonding interaction between –NH of h-BT@C@PPy and –CN of PEN, effectively promoting the interfacial polarization and remedying the internal interface defects between h-BT and PEN. Consequently, an addition of 8 wt% h-BT@C@PPy into PEN matrix raised the dielectric constant from 3.82 to 13.3 at 1 kHz, while maintaining relatively low dielectric loss (0.05@1 kHz). However, the breakdown strength showed a decreasing trend with the lowest value of 60.37 kV mm −1 . Meanwhile, the better flexibility, outstanding thermal stability (the 5% weight loss above 500 °C) as well as excellent permittivity-temperature stability was also delivered by the PEN-based composite films. This strategy furnishes a perspective to design ceramic/polymer dielectrics with high- k achieved at low filler content for the applications of organic film capacitors.
研究领域:
材料科学
·
聚合物复合材料
·
介电材料
·
纳米技术
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2011
·
IF 3.074
Ting Wu,Xiang Cai,Shaozao Tan,Hongye Li,Jiesheng Liu,Weidong Yang
In order to explore the potential of graphene (G) in removal of hazardous chemicals in waste water, chemically reduced graphene oxide was employed as the adsorbent and the adsorption characteristics of graphene toward acrylonitrile (AN), p-toluenesulfonic acid (p-TA), 1-naphthalenesulfonic acid (1-NA) and methyl blue (MB) were evaluated under laboratory conditions. The results showed that the organic chemicals with larger molecule size and more benzene rings possessed a higher adsorption speed and a higher maximum adsorption capacity on G. The maximum adsorption capacities of p-TA, 1-NA and MB on G are ∼1.43 g/g G, ∼1.46 g/g G and ∼1.52 g/g G at 30 °C, respectively, which are the highest values of p-TA, 1-NA or MB adsorption on different kinds of today's nanomaterials. Under the maximum adsorption capacity, the absorption quantity of MB on G was dependent on the initial concentration of MB, and higher temperature could facilitate the adsorption process. The G efficiency remains almost constant during the first five cycles of the adsorption–desorption process. In addition, the fluorescence spectra implied that the adsorption of MB on G was a π–π stacking adsorption process. In conclusion, the G could serve as a promising adsorbent for the removal of chemicals containing benzene rings in waste water.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
Journal of Cleaner Production
·
2021
·
IF 9.297
Yonghui Tu,Long-Fei Ren,Yuanxin Lin,H. Susan Zhou,Jiahui Shao,Yiliang He
The traditional adsorbents for antimonate (Sb(V)) in industrial effluent suffered from poor adsorption capacity due to the lack of pores or adsorption sites. Three-dimensional (3D) amidoxime-polyacrylonitrile sphere (APANS) with hierarchical pores and abundant amidoxime groups was fabricated via nanoscale thermally induced phase separation (TIPS). The effects of fabrication parameters including diluent type, PAN concentration and amidoximation time on pore structure were studied with scanning electron microscopy (SEM), mercury intrusion instrument (MIP), fourier transform infrared spectrophotometer (FT-IR) and X-ray photoelectron spectroscopy (XPS). Results showed that APANS fabricated from 2% PAN/DMSO solution and amidoximated for 20 min had coarse surface, numerous mesopores , high porosity (88.5%) and large pore volume (20.5 mL/g). The pore formation mechanism revealed that the hierarchical pores were derived from multiscale DMSO crystals shaped by TIPS. Adsorption kinetics results showed that kinetics data were well fitted by pseudo-second-order model ( R 2 > 0.99) and the mesopores accelerated the adsorption (equilibrium time of 4 h) due to enormous surface excess and group exposure. Adsorption isotherm could be modeled by Freundlich ( R 2 > 0.99) and maximum adsorption capacity was 683.6 mg/g. The adsorption thermodynamics was also investigated, indicating the spontaneous and exothermic adsorption process . APANS exhibited excellent selectivity towards common anions (Cl − , SO 4 2− , NO 3 − and PO 4 3− ) and reliable reusability (preserving 80% capacity after five cycles). This adsorbent provided a clean and sustainable strategy for Sb(V) removal from aqueous environment by superhigh capacity, fast rate and reliable reusability.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）