Reaction Kinetics Mechanisms and Catalysis
·
2017
·Vol. 122
·期 1
·357-367
·
IF 1.264
Wu Shuxiang,Wang Wenhang,Fang Yuzhen,Kong Xiangjin,Liu Junhai
Silicotungstic acid (STA) modified ZIF-8 catalyst was developed by simple impregnation method for Friedel–Craft acylation reaction. The best performance was observed on 20 wt% STA/ZIF-8, over which conversion of anisole and selectivity towards p-benzoylanisole reached 99.2 and 93.5%, respectively. N 2 physisorption, XRD, FT-IR, TGA and Pyridine FT-IR characterizations indicated that introduction of STA to ZIF-8 did not change its main structure but increased its acid site density, which promised enhanced catalytic performance of the obtained catalyst. Moreover, the performance of the catalyst was further proved through a series of substrates with electron donor or withdraw substitution group, since all of substrates could be converted to corresponding p-isomer effectively.
研究领域:
化学
·
催化科学
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DOI
高影响因子
CHEMICAL RESEARCH IN CHINESE UNIVERSITIES
·
2023
·Vol. 39
·期 6
·1058-1063
·
IF 3.1
Wang Chenghui,Yu Zhichao,Bai Qinghong,Pan Dingwu,Prior Timothy J.,Tao Zhu,Redshaw Carl,Xiao Xin
T he binding behavior of cucurbit[8]uril(Q[8]) and p -hydroxybenzoic acid(p-HBA) has been investigated using 1 H NMR titration experiments, UV-Vis absorption, isothermal titration calorimetry(ITC), and X-ray crystallography. Results revealed that the Q[8] can accommodate two p -HBA molecules to form a 1:2 host-guest inclusion complex in solution, namely ( p -HBA) 2 @Q[8]. From a poorly scattering crystal, we were able to identify two symmetry unique Q[8] rings, but with different p -HBA fillings. The structure can be represented as Q[8]+1.5 p -HBA, which gives Q[8]@(p-HBA) 2 ·Q[8]@ p -HBA as the structural formula. This supramolecular structure was screened for its ability to capture iodine. The experimental results showed that the adsorption efficiency of the supramolecular organic framework material for iodine capture was 43.8%, with an equilibrium adsorption capacity of 223.3 mg/g.
研究领域:
超分子化学
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材料科学
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产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2022
·Vol. 29
·期 23
·35204-35216
·
IF 5.19
Song Xu,Mo Jingqian,Fang Yuting,Luo Shumin,Xu Jingjing,Wang Xu
We prepared a double-layer magnetic nanocomposite Fe 3 O 4 @ZIF-8@ZIF-67 by layer-by-layer self-assembly. Fe 3 O 4 @ZIF-8@ZIF-67 was used to remove tetracycline from an aqueous solution via a combination of adsorption and Fenton-like oxidation. Depending on the outstanding porous structure of the Fe 3 O 4 @ZIF-8@ZIF-67, a high adsorption capacity for tetracycline was 356.25 mg g −1 , with > 95.47% removal efficiency within 100 min based on Fenton-like oxidation. To better understand the mechanisms involved in integrated adsorption and Fenton-like oxidation, various advanced characterization techniques were used to monitor the changes in morphology and composition of Fe 3 O 4 @ZIF-8@ZIF-67 before and after removal of tetracycline. Scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) all supported adsorption and Fenton oxidation of tetracycline. This study extends the application of Fe 3 O 4 @ZIF-8@ZIF-67 for environmental remediation. Graphical abstract
研究领域:
环境科学
·
材料科学
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DOI
高影响因子
ChemSusChem
·
2024
·
IF 7.5
Yanan Dong,Ju Bai,Luqi Xiao,Shangqing Chen,Lu Bai,Huaigang Cheng,Linglong Shan,Junfeng Wang,Yi Nie
Graphical Polyethyleneimine (PEI)-templated ZIF-8 (PEI-ZIF-8) was synthesized and incorporated into the PEI aqueous solution, then interfacial polymerized with trimesoyl chloride (TMC) to obtain the PEI-ZIF-8 modified polyamide NF membrane. The optimal PEI-ZIF-8-TMC membrane exhibits a permeance of 9 L/h m 2 bar and a Mg 2+ /Li + separation factor (SF) of 19. MOFs-modified nanofiltration (NF) membranes have been gained a lot of attention due to their favorable permeability and ion separation performance. Nevertheless, the prevailing preparation techniques are afflicted by the incompatibility of MOFs with polymers and the facile loss of MOFs. In this work, polyethyleneimine (PEI)-templated ZIF-8 (PEI-ZIF-8) was synthesized and incorporated into the PEI aqueous solution, then interfacial polymerized with trimesoyl chloride (TMC) to obtain the PEI-ZIF-8 modified polyamide NF membrane. This PEI modified strategy could endow the ZIF-8 nanoparticles with positively charged properties to avoid the aggregation and increase the interfacial compatibility with the polyamide. Meanwhile, the appropriate pore size of ZIF-8 (3.4 Å), which is between the hydration sheath surrounding of Li + (2 Å) and Mg 2+ (4.2 Å) impart the membrane with precise Mg 2+ /Li + separation ability. The optimal PEI-ZIF-8-TMC membrane exhibits a permeance of 9 L/h m 2 bar and a Mg 2+ /Li + separation factor (SF) of 19, both of which surpass the performance of the pure PEI-TMC membrane, which has a permeance of 4 L/h m 2 bar and a Mg 2+ /Li + separation factor of 11. Meanwhile, the membrane exhibited excellent long-term stability of 85 h. This novel approach to preparing MOFs-modified NF membrane represents a promising avenue for the separation of lithium and magnesium.
研究领域:
材料科学
·
分离技术
·
纳米科技
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产品关联
DOI
PubMed
高影响因子
THERMOCHIMICA ACTA
·
2024
·
IF 3.1
Shuhang Li,Xianglin Liao,Zhinan Zhang,Xue Chen,Luobiao Hong,Cong Liu,Suilian Luo,Qiong Hou,Yuhai Wang,Guang Shi
The thermal stability of zeolitic imidazolate framework-8 (ZIF-8) for poly(vinyl chloride) (PVC) has received attention, but its thermal stabilization mechanism needs further clarification. Herein, the stearic acid-modified ZIF-8 with high specific surface area and large pore volume was effectively synthesized by using zinc stearate as the zinc source for the first time. Modification of stearic acid results in larger adsorption capacity of ZIF-8 for HCl and better thermal stability effect for PVC, especially long-term thermal stability. Moreover, the thermal stability mechanism of ZIF-8 for PVC was demonstrated by experiments and theoretical calculations. In addition to absorbing HCl to eliminate autocatalytic degradation of PVC, ZIF-8 disintegrates and may form 2-methylimidazole-Zn-Cl salt complex instead of free ZnCl2, avoiding the negative zinc burning effect. Furthermore, the Diels-Alder reaction between imidazole ring and degraded PVC prevents the extension of the conjugated double bonds of PVC and delays the deepening of the color of PVC.
研究领域:
材料科学
·
高分子化学
·
热力学
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DOI
高影响因子
RSC Advances
·
2018
·Vol. 8
·期 57
·32740-32746
·
IF 2.936
Ya-feng Jin,Chuang-ye Ge,Xiao-bo Li,Miao Zhang,Guang-ri Xu,Dong-hao Li
Herein, we fabricated a sensitive rutin electrochemical sensor via modifying glassy carbon electrode (GCE) with zeolitic imidazolate framework-8 (ZIF-8) and acetylene black (AB) in the presence of chitosan (CS). The electrochemical activity and experimental parameters of the ZIF-8-AB-CS/GCE sensor were investigated by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Under the optimal conditions, the sensor presented a reasonable linear response in the range of 0.1–10 μM with a limit of detection (LOD) as low as 0.004 μM (S/N = 3). The sensor possessed good reproducibility and high stability, and was successfully applied to detect rutin tablet samples with satisfactory results, which was attributed to the synergistic effect between ZIF-8 and AB. Meanwhile, the sensor displayed a potential application for detection of other analytes in real samples. Furthermore, a probable interaction mechanism was proposed to account for the interaction between rutin and the nanocomposite electrode, which was not discussed in previous reports.
研究领域:
分析化学
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材料科学
·
药物分析
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF BIOMATERIALS APPLICATIONS
·
2019
·
IF 2.442
Xin Zhang,Jian Wang,Jiaxin Wu,Xiaoge Jiang,Xibo Pei,Junyu Chen,Qianbing Wan,Chao Huang
Nanoscale zeolitic imidazolate framework-8 coating with certain density can significantly improve the osteogenic activity of titanium implants both in vitro and in vivo. In this study, we loaded dimethyloxalylglycine into zeolitic imidazolate framework-8-modified implants (Z-AHT) to enhance the angiogenic activity, and the obtained products were denoted as D-AHT. Firstly, we characterized the specimens via scanning electron microscopy, Fourier transform infrared spectroscopy, powder X-ray diffraction, and surface contact angle. Then, the release kinetics of both zinc ions and dimethyloxalylglycine were investigated. To illustrate the combined effects of surface topography and chemistry (zeolitic imidazolate framework-8 and dimethyloxalylglycine) on osteogenic and angiogenic activity, MC3T3-E1 preosteoblast cells and human umbilical vein endothelial cells were respectively cultured on D-AHT. Pure Ti and Z-AHT were designated as control groups. As evidenced by the expression of osteogenic genes (Alp, Col1, Opg, and Runx2) and the secretion of ALP protein, D-AHT showed comparable osteogenic activity to Z-AHT which was better than that of Ti. Further angiogenesis assay revealed a better human umbilical vein endothelial cell migration on D-AHT, suggesting that D-AHT can be an attractive candidate for application in implant surface modification.
研究领域:
生物材料
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组织工程
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细胞生物学
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产品关联
DOI
PubMed
高影响因子
Nanomaterials
·
2023
·Vol. 13
·期 11
·1779
·
IF 5.3
Shunyu Zhang,Jinxia Li,Liang Yan,Yue You,Feng Zhao,Jixing Cheng,Limin Yang,Yanqi Sun,Qingchao Chang,Ru Liu,Yunhui Li
Telomerase is constitutively overexpressed in the majority of human cancers and telomerase inhibition provides a promising broad-spectrum anticancer therapeutic strategy. BIBR 1532 is a well-known synthetic telomerase inhibitor that blocks the enzymatic activity of hTERT, the catalytic subunit of telomerase. However, water insolubility of BIBR 1532 leads to low cellular uptake and inadequate delivery and thus, limits its anti-tumor effects. Zeolitic imidazolate framework-8 (ZIF-8) is considered as an attractive drug delivery vehicle for improved transport, release and anti-tumor effects of BIBR 1532. Herein, ZIF-8 and BIBR[email protected]were synthesized, respectively, and the physicochemical characterizations confirmed the successful encapsulation of BIBR 1532 in ZIF-8 coupled with an improved stability of BIBR 1532. ZIF-8 could alter the permeability of lysosomal membrane probably by the imidazole ring-dependent protonation. Moreover, ZIF-8 encapsulation facilitated the cellular uptake and release of BIBR 1532 with more accumulation in the nucleus. BIBR 1532 encapsulation with ZIF-8 triggered a more obvious growth inhibition of cancer cells as compared with free BIBR 1532. A more potent inhibition on hTERT mRNA expression, aggravated G0/G1 arrest accompanied with an increased cellular senescence were detected in BIBR[email protected]cancer cells. Our work has provided preliminary information on improving the transport, release and efficacy of water-insoluble small molecule drugs by using ZIF-8 as a delivery vehicle.Keywords:ZIF-8;drug loading;transport;protonation effect;telomerase inhibitor
研究领域:
药学
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癌症研究
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药物递送系统
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分子生物学
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产品关联
DOI
PubMed
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2024
·
IF 3.8
Yongjiang Shan,Mingliang He,Fei Zhang,Yingdong Yang,Yifei Wang,Tian Gui,Yuqin Li,Zhipeng Wang,Xiangshu Chen
The deployment of green hydrogen energy plays a pivotal role in propelling sustainable development and achieving carbon neutrality. Separating H2 and CH4 is a crucial step in industrial hydrogen purification. Metal–organic framework (MOF) membranes offer vast prospects for applications in gas separation. Breaking the “trade-off” between permeance and selectivity has consistently remained a primary challenge in the realm of separation membranes. In this work, highly permeable H2 separation ZIF-8 membranes were fabricated on a vertical graphene (VG)-modified α-Al2O3 support (VG@α-Al2O3), and the VG layer can afford active sites for synthesizing ZIF-8 membranes and provide more gas transport path to reduce the mass transfer resistance. With the aid of O2 plasma in improving the hydrophilicity of the VG layer, nano-ZIF-8 crystals can be synthesized on the VG to act as seeds (ZIF-8@VG@α-Al2O3) for membrane synthesis, and green synthesis membranes were realized in aqueous solution. At 90 °C for 12 h, about 900 nm-thick membrane layers were synthesized, with a high H2 permeance of 1.8 × 10–6 mol·m–2·s–1·Pa–1 and H2/CH4 separation factor of 9.6. After the synthesis period was increased to 24 h, the denser ZIF-8 membrane resulted in a higher H2/CH4 selectivity (17.2). In contrast to the MOF membranes described in previous studies, satisfactory hydrogen permeance of ZIF-8 membranes can be achieved while maintaining high selectivity.
研究领域:
材料科学
·
膜分离技术
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纳米材料
·
能源化学
·
环境科学
✓ 已验证
DOI
高影响因子
JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY
·
2015
·Vol. 54
·期 8
·1056-1064
·
IF 3.113
Wenjuan Wang,Ling Lin,Jiang Lu,Hui Liang,Hao Feng,Lifen Hu
Triblock copolymers (MPEG- b -PCEMA- b -PHQHEMA) bearing cinnamoyl and 8-hydroxyquinoline side groups with different block length are synthesized by a two-step reversible addition fragmentation chain transfer polymerization of cinnamoyl ethyl methacrylate (CEMA) and 2-((8-hydroxyquinolin-5-yl)methoxy)ethyl methacrylate (HQHEMA), respectively. The self-assembly of MPEG- b -PCEMA- b -PHQHEMA in mixture of THF and ethanol is investigated by varying the ratio of THF and ethanol. Spheric micelles with diameter of 63.7 nm and polydispersity of 0.128 are obtained for MPEG 113 - b -PCEMA 15 - b -PHQHEMA 17 in THF/ethanol with a volume ratio (v/v) of 5/5. The PCEMA inner shell of the resulted micelles is photo-crosslinked under UV radiation to give stabilized micelles. The complex reaction of the stabilized micelles with Zn(II) is investigated under different conditions to give zinc(II)-bis(8-hydroxyquinoline)(Znq 2 )-containing micelles. When the complex reaction is carried out in THF/ethanol (v/v = 5/5) or THF/toluene (v/v = 6/4) with zinc acetate, fluorescent Znq 2 -containing micelles are obtained without obvious change in diameters and morphologies. The fluorescent micelles exhibit green emission with λ max at 520 nm. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54 , 1056–1064
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
·
2022
·
IF 8.943
Longwei Yin,Wenpeng Li,Shen Lin,Gary Owens,Zuliang Chen
Arsenic contamination is an increasing global environmental problem, especially in mining industry wastewater where both arsenite (As(III)) and arsenate (As(V)) have been routinely detected. In this paper, a novel porous metal-organic framework material (ZIF-8) was composited with iron nanoparticles (FeNPs) to form a functional material (ZIF-8@FeNPs) for the simultaneous removal of As(III)/(V) from wastewater. The material effectively removed both As(III) and As(V) with removal efficiencies of 99.9 and 71.2%, respectively. Advanced characterization techniques including X-ray photoelectron spectroscopy (XPS) and Fourier infrared (FTIR) indicated that removal of As(III) and As(V) involved complex formation. Adsorption kinetics followed a pseudo-second order kinetics indicating adsorption involved chemisorption . After four cycles of reuse the he removal rate of As species was still relatively high at > 60% When ZIF-8@FeNPs were used to remove As from real wastewater from acid mines the removal efficiency was 94.27%. Finally, a As(III) and As(V) removal mechanism was proposed.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Sihan Ai,Yong Xiang,Xue Chen,Yanlin Zhang,Yufei Zhang,Kangning Lv,Xin Chen,Daoyong Yu,Baosheng Ge,Fang Huang
Carbon dioxide capture, utilization and storage (CCUS) technology is considered an effective solution to achieve carbon neutrality. In CCUS, chemical absorption stands out as an efficient CO 2 capture method suitable for environments with low CO 2 partial pressures. This study aims to enhance the CO 2 capture performance of monoethanolamine (MEA) solution by employing zeolitic imidazolate frameworks ZIF-8 and ZIF-67 as catalysts. The impacts of catalyst concentration and experimental temperature on the quantity, rate of absorption, rate of desorption, and reusability of MEA for CO 2 absorption were investigated. Changes in the volume concentration of CO 2 in the mixed gas were monitored to assess these parameters. The results demonstrated that at a catalyst concentration of 150 mg/mL for ZIF-8 and 125 mg/mL for ZIF-67, MEA achieved CO 2 absorption quantity of 22.22 % and 18.89 %, respectively. This corresponded to substantial increases of 63.39 % and 125.9 % in the CO 2 maximum absorption rate of MEA solution. While the maximum desorption rate of MEA was enhanced by 49.71 % and 83.28 %. In conclusion, the introduction of ZIF-8 and ZIF-67 catalysts effectively catalyzed the CO 2 capture process, significantly enhancing the CO 2 capture quantity of MEA and ensuring energy-efficient regeneration of MEA. This study provides a novel approach for improving the performance of MEA in terms of capturing CO 2 .
研究领域:
化学工程
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环境科学
·
材料科学
✓ 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）