JOURNAL OF CATALYSIS
·
2018
·
IF 6.759
Jian-Dong Song,Tong-Yang Song,Ting-Ting Zhang,Yun Wang,Meng-Fei Luo,Ji-Qing Lu
A series of supported V 2 O 5 /MgF 2 catalysts were prepared and tested for dehydrofluorination of 1,1,1,3,3-pentafluoropropane (HFC-245fa) to synthesize 1,3,3,3-tetrafluoropropene (HFO-1234ze). The addition of V 2 O 5 in MgF 2 resulted in up to 5-fold increase in HFC-245fa conversion (from 19.2 to 95.2%) and much enhanced catalyst stability. Characterization results revealed that the dehydrofluorination initiated on the MgF 2 support triggered the transformation of V 2 O 5 to vanadium oxyfluoride (VOF x ) species via the reaction between V 2 O 5 and HF, and such species were responsible for the improved activity as they had much higher turnover frequencies (TOFs) than the MgF 2 (0.762 s −1 v.s. 0.026 s −1 at 320 °C). The kinetic results indicated that the 3.1V 2 O 5 /MgF 2 had much lower activation energy (44.6 ± 1.9 kJ mol −1 ) than the MgF 2 (69.0 ± 0.8 kJ mol −1 ). Accordingly, reaction mechanism on the V 2 O 5 /MgF 2 catalyst was proposed, which included slow dehydrofluorination on MgF 2 and fast dehydrofluorination on the VOF x species.
研究领域:
催化化学
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材料科学
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环境化学
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DOI
高影响因子
Catalysts
·
2021
·Vol. 11
·期 11
·1268
·
IF 4.146
Shucheng Wang,Chuanzhao Wang,Houlin Yu,Wei Yu,Yongnan Liu,Wucan Liu,Feixiang Zhou,Wanjin Yu,Jiuju Wang,Jianjun Zhang,Wenfeng Han
A BaF(p-BDC)0.5catalyst was prepared by solid state reaction at room temperature with Ba(OH)2as precursor, NH4F as F source, and H2(p-BDC) as organic ligand. The calcined samples were used as catalysts for dehydrochlorination of 1-chloro-1,1-difluoroethane to generate vinylidene fluoride (VDF) at 350 °C. Commercial production of VDF is carried out at 600–700 °C. Clearly, pyrolysis of the BaF(p-BDC)0.5catalyst provided a promising way to prepare VDF at low temperatures. Prior to calcination, the activity of the BaF(p-BDC)0.5catalyst was low. Following calcination at high temperatures, BaF(p-BDC)0.5decomposed to BaF2and BaCO3, and then the catalyst was chlorinated and fluorinated to BaClF, which showed high activity and stable VDF selectivity for dehydrochlorination of 1-Chloro-1,1-Difluoroethane to VDF.Keywords:barium fluoride;catalytic pyrolysis;dehydrochlorination;1-chloro-1,1-difluoroethane;vinylidene fluoride
研究领域:
化学工程
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材料科学
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DOI
高影响因子
POWDER TECHNOLOGY
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2025
·
IF 4.6
Xueqin Liao,Jianzhong Liu,Mengxia Sun,Xiaohui Xue
Fluoride has shown great potential for improving the burning rate and combustion efficiency of aluminum (Al) particles. Herein, the effects of metal fluoride (ferric fluoride, FeF 3 ) and organic fluoride (polytetrafluoroethylene, PTFE) on the combustion of Al particles were comparatively investigated using various characterization methods. The results showed that both FeF 3 and PTFE could improve the thermal reaction properties of Al particles, including thermal oxidation rate, heat release, mass gain, and thermal oxidation efficiency, and the improvement of FeF 3 was better. Thermal reaction curves and tube furnace tests together demonstrated that fluoride and Al particles undergo pre-ignition reaction at low heating rates. Combustion diagnostic results and condensed combustion products (CCPs) analysis of the samples revealed that both fluorides reduced the ignition delay time and increased the combustion intensity, burning rate, combustion efficiency and maximum combustion temperature. When ammonium perchlorate (AP) was not added, PTFE improved the combustion performance of Al particles better due to its high gas production characteristics. PTFE is not as good as FeF 3 after adding AP. Furthermore, varying the FeF 3 content in the binary mixture (Al/FeF 3 ) between 5 % and 20 % did not significantly affect the combustion characteristics of the samples. Interestingly, the high-speed camera captured the jetting phenomenon of Al droplets during combustion, which is attributed to the erosive effect of F on the alumina cap. The jet phenomenon is the direct evidence of the reaction between Al particles and F during combustion, which provides new insights into the complex reaction mechanism between the two. Statistics on a large number of particles indicated that FeF 3 can increase the frequency of the particle jet phenomenon. Finally, the phenomenological mechanism of fluoride promoting Al particle combustion is proposed. Considering the catalytic effect of metals and their corresponding oxides on AP, the addition of metal fluorides to AP-based energetic materials may be a more preferable option.
研究领域:
材料科学
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燃烧学
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DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2012
·Vol. 125
·期 4
·3068-3075
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IF 1.289
Yunquan Jin,Baoqing Shentu,Zhixue Weng
Fluorine-containing polyester (FPE) was synthesized by the reaction of phthalic anhydride, epichlorohydrin, and 2,2,3,3-tetrafluoropropyl glycidyl ether (TFGE) at the catalysis of tetraethylammonium bromide using 1,4-butanediol as the initiator. The structure of FPE was characterized by 1 H NMR and 19 F NMR, and the result showed that the fluorine in TFGE was introduced into FPE. Fluorine content in FPE was determined by oxygen-flask combustion and fluoride selective electrode. It was found that fluorine content in FPEs increased with the increase of TFGE content. The wettability of water and oil on the cured coating based on FPE was investigated by contact angle meter. Contact angles of water and diiodomethane on the cured coatings first increased with the increase of the fluorine content in FPEs and then remained constant. The X-ray photoelectron spectroscopic analysis showed that the F / C molar ratio on the coatings surface was much higher than the overall F / C molar ratio, which indicated that fluoroalkyl groups in FPEs had enriched on the coatings surface. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
研究领域:
材料科学
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化学工程
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DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2019
·Vol. 31
·期 3
·616-629
·
IF 2.162
Long Zhang,Qinggang Kong,Fanxin Kong,Taolin Liu,Haiyan Qian
A novel fluorinated chain extender, (1-(ethyl(2-hydroxyethyl)amino)-3- ((3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)oxy)propan-2-ol) (FPO), was synthesized and characterized by nuclear magnetic resonance (NMR), Fourier transform infrared (FTIR), and elemental analysis. Poly (ether urethane)s containing various amounts of the chain extender with fluorinated side chains (FPUs) were prepared by isophorone diisocyanate (IPDI), polytetra-methylene-ether-glycol (PTMG), 3-aminopropyltriethoxysilane (KH-550), and 1,4-butandiol (BDO). Films of FPUs were investigated by water absorption, contact angle, pencil hardness, adhesive force, and thermal analysis. Coating FPUs on micro-nano concave-convex structure plate realizes superhydrophobic performance. Scanning electron microscope (SEM) and atomic force microscopy (AFM) demonstrated that there is a lot of irregular concave-convex structure, which forms a typical air cushion model. X-ray photoelectron spectroscopy (XPS) analysis showed that surface fluorine content is 165% more than that of film average fluorine content. The superhydrophobic plate with 10% or higher F-containing FPUs coating is of outstanding chemical corrosion resistance, excellent solvent resistance, and wear resistance.
研究领域:
材料科学
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表面化学
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DOI
高影响因子
Catalysts
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2020
·Vol. 10
·期 3
·355
·
IF 3.52
Wucan Liu,Yongnan Liu,Kabozya M. Mardochee,Zhikun Wang,Shucheng Wang,Wei Yu,Jianjun Zhang,Wenfeng Han
SrF2promotes the dehydrochlorination (DeHCl) of 1,1-difluoro-1-chloroethane, which is the key process for the manufacture of VDF (vinylidene fluoride), one of the most typical fluorinated monomers. However, the selectivity is low as dehydrofluorination (DeHF) to VCF (vinylidene chlorofluoride) competes with the formation of VDF. In this study, SrF2@C (SrF2embedded in carbon) and SrF2@NC (N-doped carbon) catalysts were fabricated following calcination in N2with SrC2O4, PVDF (poly vinylidene fluoride) and urea as the precursors. The catalysts were characterized by XRD, SEM, TEM, and XPS. The results show that both the calcination temperature and N-doping play an important role in the conversion of HCFC-142b and the selectivity to VDF and VCF. Calcination at elevated temperatures enhances the Sr-C interaction. For SrF2@C, improved interaction facilitates withdrawing electrons from Sr by the carbon support. By contrast, the strong interaction of Sr with N-doped carbon supply electrons from N species to Sr. The electron deficiency of Sr is favorable for the adsorption of F with higher electronegativity and consequently, DeHF reaction forming VCF. The supply of electrons to Sr by the support improves the formation of VDF (DeHCl). The present work provides a potential strategy for the improvement of selectivity to the target product.Keywords:dehydrochlorination;dehydrofluorination;metal–support interaction;strontium fluoride;vinyl difluoride
研究领域:
化学工程
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材料科学
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DOI
高影响因子
CHIRALITY
·
2023
·Vol. 35
·期 4
·247-255
·
IF 2
Yan He,Mengdi Qin,Mo Li,Defu Zhi,Baocheng Tian,Feng Qin
Flurbiprofen axetil (FA) is a prodrug of flurbiprofen (FP), and it is hydrolyzed to the active FP by carboxylesterase in plasma after intravenous injection. The pharmacological action of FP is closely related to its chirality, and S-FP shows better analgesic effects than R-FP. Therefore, it is of great significance to compare the in vivo pharmacokinetic behaviors of R-FP and S-FP. In this study, we designed a sensitive high performance liquid chromatography–tandem mass spectrometry method and used CHIRALPAK-IG3 column for chiral separation to quantify the concentrations of R-FP and S-FP in rat plasma. The results show that this method can accurately and effectively analyze the contents of R-FP and S-FP in plasma. In addition, the systemic exposure was approximately 3.09-folds for the S-FP compared with the R-FP following intravenous administration of the FA to rats at a single dose of 4.5 mg/kg. More importantly, the clearance rate of S-FP is significantly smaller than that of R-FP. Therefore, the development of S-FA injectable emulsion for clinical treatment of postoperative pain is very necessary.
研究领域:
药理学
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分析化学
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产品关联
DOI
PubMed
高影响因子
CHINESE CHEMICAL LETTERS
·
2025
·
IF 8.9
Bin Wang,Qingqing Zhou,Junjie Lu,Chuyang Li,Mengmeng Fan,Wenwei Ding,Bifu Sheng,Wenjuan Zhu,Qian Ni,Huixin Chen,Xiang Han
Poly(vinylidene fluoride- co -hexafluoropropylene) (PVDF-HFP)-based solid polymer electrolytes show great potential for high energy lithium metal batteries, however, the residual solvent and related severe side reactions limit its development. Herein, a PVDF-HFP-based solid polymer electrolyte modified by fluorobenzene (FB) co-solvent is designed to address these problems. The introduced FB with weak solvation interaction regulates the coordination environment and induces anions to enter the solvation structure, generating more contact ion pairs (CIPs) and aggregates (AGGs). In addition, the anions-derived LiF-rich interphases help to improve the interface stability against Li metal. As a result, the FB-PVDF-HFP achieves high ionic conductivity (4.1 × 10 −4 S/cm) and low activation energy (0.125 eV) at room temperature. In addition, Li||Li symmetric cells using FB-PVDF-HFP electrolyte can achieve uniform and dendrite-free lithium deposition/stripping in the long-term cycling over 2300 h. The assembled solid-state Li|FB-PVDF-HFP|LFP full cell shows improved rate performance and cycling performance (600 cycles at 0.5 C and 450 cycles at 3 C) at room temperature. This work verifies the feasibility of fluorinated terminated solid polymer electrolytes on its lithium-ion transport and interfacial stability in lithium metal batteries.
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DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2017
·
IF 3.387
Jian-Wei Luo,Jian-Dong Song,Wen-Zhi Jia,Zhi-Ying Pu,Ji-Qing Lu,Meng-Fei Luo
Catalytic dehydrofluorination of 1,1,1,3,3-pentafluoropropane to 1,3,3,3-tetrafluoropropene was performed on a series of fluorinated NiO/Cr 2 O 3 catalysts. The NiO/Cr 2 O 3 catalysts were more active than the Cr 2 O 3 because the new acid sites provided by NiF 2 had higher turnover frequencies (9.43 × 10 −3 − 12.08 × 10 −3 s −1 ) than those on the Cr 2 O 3 (4.55 × 10 −3 s −1 ). Also, the NiO/Cr 2 O 3 was more stable than the Cr 2 O 3 due to its lower density of surface acid sites, which alleviated the coke deposition on the catalyst as evidenced by the Raman spectroscopic results. The kinetic results revealed that the15NiO/Cr 2 O 3 had much lower activation energy (63.6 ± 4.5 kJ mol −1 ) than the Cr 2 O 3 (127.6 ± 3.8 kJ mol −1 ). Accordingly, different reaction pathways on the two catalysts were proposed, which involved the cleavage of the C F and C H bonds on the surface acid and base sites, respectively.
研究领域:
化学工程
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
·
2024
·
IF 6.2
Chao Wen,Huan Chen,Yunbing Tang,Hang Lin,Congcong Xu,Yingfen Ying,Yang Zhu,Xinjun Miao,Ren-shan Ge,Chao Chen,Shangqin Chen
Per- and polyfluoroalkyl (PFAS) substances are enduring industrial materials. 17β-Hydroxysteroid dehydrogenase isoform 1 (17β-HSD1) is an estrogen metabolizing enzyme, which transforms estrone into estradiol in human placenta and rat ovary. Whether PFAS inhibit 17β-HSD1 and what the structure-activity relationship (SAR) remains unexplored. We screened 18 PFAS for inhibiting human and rat 17β-HSD1 in microsomes and studied their SAR and mode of action(MOA). Of the 11 perfluorocarboxylic acids (PFCAs), C8-C14 PFCAs at a concentration of 100 μM substantially inhibited human 17β-HSD1, with order of C11 (half-maximal inhibition concentration, IC 50 , 8.94 μM) > C10 (10.52 μM) > C12 (14.90 μM) > C13 (30.97 μM) > C9 (43.20 μM) > C14 (44.83 μM) > C8 (73.38 μM) > others. Of the 7 per- and poly-fluorosulfonic acids (PFSAs), the potency was C8S (IC 50 , 14.93 μM) > C7S (80.70 μM) > C6S (177.80 μM) > others. Of the PFCAs, C8-C14 PFCAs at 100 μM markedly reduced rat 17β-HSD1 activity, with order of C11 (IC 50 , 9.11 μM) > C12 (14.30 μM) > C10 (18.24 μM) > C13 (25.61 μM) > C9 (67.96 μM) > C8 (204.39 μM) > others. Of the PFSAs, the potency was C8S (IC 50 , 37.19 μM) > C7S (49.38 μM) > others. In contrast to PFOS (C6S), the partially fluorinated compound 6:2 FTS with an equivalent number of carbon atoms demonstrated no inhibition of human and rat 17β-HSD1 activity at a concentration of 100 μM. The inhibition of human and rat enzymes by PFAS followed a V-shaped trend from C4 to C14, with a nadir at C11. Moreover, human 17β-HSD1 was more sensitive than rat enzyme. PFAS inhibited human and rat 17β-HSD1 in a mixed mode. Docking analysis revealed that they bind to the NADPH and steroid binding site of both 17β-HSD1 enzymes. The 3D quantitative SAR (3D-QSAR) showed that hydrophobic region, hydrogen bond acceptor and donor are key factors in binding to 17β-HSD1 active sites. In conclusion, PFAS exhibit inhibitory effects on human and rat 17β-HSD1 depending on factors such as carbon chain length, degree of fluorination, and the presence of carboxylic acid or sulfonic acid groups, with a notable V-shaped shift observed at C11.
研究领域:
环境毒理学
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分子生物学
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药理学
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产品关联
DOI
PubMed
高影响因子
MOLECULES
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2025
·Vol. 30
·期 15
·3166
·
IF 4.6
Ling Chen,Changying Hu,Zhiwei Wang
The rapid growth of plant-based biodegradable tableware, driven by plastic restrictions, necessitates rigorous safety assessments of potential chemical contaminants like per- and polyfluoroalkyl substances (PFASs). This study comprehensively evaluated PFAS contamination risks in commercial sugarcane pulp tableware, focusing on the residues of five target PFASs (PFOA, PFOS, PFNA, PFHxA, PFPeA) and their migration behavior under simulated use and takeout conditions. An analysis of 22 samples revealed elevated levels of total fluorine (TF: 33.7–163.6 mg/kg) exceeding the EU limit (50 mg/kg) in 31% of products. While sporadic PFOA residues surpassed the EU single compound limit (0.025 mg/kg) in 9% of samples (16.1–25.5 μg/kg), the levels of extractable organic fluorine (EOF: 4.9–17.4 mg/kg) and the low EOF/TF ratio (3.19–10.4%) indicated inorganic fluorides as the primary TF source. Critically, the migration of all target PFASs into food simulants (water, 4% acetic acid, 50% ethanol, 95% ethanol) under standardized use conditions was minimal (PFOA: 0.52–0.70 μg/kg; PFPeA: 0.54–0.63 μg/kg; others < LOQ). Even under aggressive simulated takeout scenarios (50 °C oscillation for 12 h + 12 h storage at 25 °C), PFOA migration reached only 0.99 ± 0.01 μg/kg in 95% ethanol. All migrated levels were substantially (>15-fold) below typical safety thresholds (e.g., 0.01 mg/kg). These findings demonstrate that, despite concerning residue levels in some products pointing to manufacturing contamination sources, migration during typical and even extended use scenarios poses negligible immediate consumer risk. This study underscores the need for stricter quality control targeting PFOA and inorganic fluoride inputs in sugarcane pulp tableware production.
研究领域:
环境化学
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食品安全
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材料科学
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分析化学
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高分子科学
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产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL RESEARCH
·
2025
·
IF 7.7
Chu-Hong Zhu,Xiao-Jun Luo,Xi Chen,Peng-Peng Chen,Ke Lan Guan,Yan-Hong Zeng,Bi-Xian Mai
Amphibians are sensitive biomonitors of environmental pollutants. However, existing research on per- and polyfluoroalkyl substances (PFASs) between different species of amphibians is limited. In the present study, water, soil, tiger frog ( Hoplobatrachus chinensis ) and forest frog ( Rana chensinensis ) samples were collected from Qingyuan County, South China. The bioaccumulation, tissue distribution, and maternal transfer of 13 PFASs, including 9 perfluoroalkyl carboxylic acids (PFCAs) and 4 perfluoroalkyl sulfonic acids (PFSAs), in frogs were investigated. The ΣPFSA and ΣPFCA concentrations in frog tissues ranged from 0.25 – 36.5 and 0.75 – 226 ng/g wet weight (ww), respectively. The testis in the male frogs had the highest ΣPFCA and ΣPFSA concentrations of all tissues, while the eggs and liver exhibited the highest ΣPFSA and ΣPFCA concentrations in female frogs, respectively. The ΣPFSA and ΣPFCA concentrations were significantly higher in the tiger frogs than in the forest frogs, which could be due to the different exposure scenarios. Male frogs exhibited significantly higher ΣPFCA concentrations than female frogs, which could be due to sex-specific elimination rates for PFASs. Certain tissues exhibited a special affinity for certain PFASs, such as C14 PFCA for the testis; C8 PFSA for the skin, carcass, and eggs; and C10 PFCA for the liver and digestive tracts. Therefore, more in-depth studies are needed on the mechanism of the affinity of a certain tissue for PFASs with specific carbon chain lengths. Approximately 7.4 – 40.4% of PFASs were transferred from the maternal body to eggs, which could underestimate the maternal transfer efficiency of PFASs in frogs because the samples were collected in the early stage of frog breeding.
研究领域:
环境毒理学
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生态毒理学
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环境科学
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野生动物生物学
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生物化学
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）