JOURNAL OF ORGANOMETALLIC CHEMISTRY
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2018
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IF 1.946
Jin Li,Yajuan Wang,Shunwang Jiang,Hui Zhang
A series of novel magnetic recyclable Pd Au nanoclusters (NCs) catalysts x-PdAu r /Fe 3 O 4 @LDH (x: Pd loading in wt%, r: Au/Pd molar ratio, LDH : layered double hydroxide, here refers the typical MgAl-LDH) were synthesized by a facile polyol reduction followed sol immobilization of PdAu r –PVP on core@shell support Fe 3 O 4 @LDH. Systematic characterizations reveal that the obtained catalysts possess the honeycomb-like core@shell, and the ultrafine PdAu alloy nanoclusters with the size in 1.70–2.55 nm highly dispersed on the LDH nanoplates shell. The obtained catalysts 1.0-PdAu r /Fe 3 O 4 @LDH (r: 0.11, 0.16 and 0.48) show higher Heck activity of iodobenzene with styrene than monomentallic ones, especially 1.0-PdAu 0.16 /Fe 3 O 4 @LDH displays the highest Heck activity under the optimal condition. Moreover, the catalysts can be applied for the Heck reaction of a variety of aryl halides with alkenes , and can be conveniently separated by an external magnet and reused ten runs without significant loss of activity.
研究领域:
化学
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催化材料
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产品关联
DOI
高影响因子
Journal of Hazardous Materials Advances
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2022
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IF 0
Yurong Gu,Qi Han,Zijun Dong,Jiaxin Zhu,Chengchun Jiang,Jikun Qi
This study systematically investigated the performance of a sulfite mediated photolytic system on diatrizoate (DTZ) degradation and deiodization under different UV intensity, sulfite dosage, initial solution pH, initial DTZ concentration and co-present constituents. As compared with sole UV photolysis and sole sulfite reduction system, the UV/sulfite system performed a higher efficiency of DTZ degradation and deiodization. At the same time, the scavenging experiments were conducted by respectively adding KNO 3 , KNO 2 , MeOH and TBA, which indicated e aq − was the dominant active species responsible for the enhanced degradation and deiodination of DTZ. Effects of reaction factors showed that the UV/sulfite system was a promising technique for DTZ degradation. A complete removal of DTZ (40 µM) could be obtained under the UV intensity of I 0 (6.67 × 10 −7 einstein/cm 2 ∙s), sulfite dosage of 0.50 mM and pH ranging from 8∼10. In addition, the intermediate products of DTZ degradation were identified and possible degradation mechanism was proposed. Four possible products including TP504, TP488, TP486 and TP236 were obtained in this study. The main degradation pathways might include protonation, deiodination, substitution and heterocyclic formation.
研究领域:
环境科学
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化学工程
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DOI
Journal of Materials Chemistry A
·
2020
·Vol. 8
·期 29
·14634-14643
·
IF 11.301
Chuan-Shu He,Rong-Rong Ding,Guan-Nan Zhou,Di He,Peng Fan,Xiao-Hong Guan,Yang Mu
Surface passivation is one of the most challenging aspects in the successful application of zero-valent iron (ZVI) for water decontamination, especially when oxygen is inevitably present. This study found that the coexistence of HA ranging from 0 to 40.0 mg-C/L appreciably improved the pseudo-first-order kinetic rate constant of pollutant diatrizoate (DTA) reduction by ZVI from 0.0454 to 0.1365 h−1 under aerobic conditions. For the first time, it revealed that the coexistence of HA could accelerate the reductive removal of organic contaminants via ZVI surface depassivation rather than the previously proposed electron-shuttle mechanism under aerobic conditions. Interestingly, both DTA removal and Fe0 consumption were found to undergo two stages in the presence of HA, with an initial slight enhancement attributed to the Fe(III)–HA complex formation partially suppressing iron precipitation, followed by a remarkable promotion arising from the HA-associated iron oxide detachment from the Fe0 surface. These findings not only provide a good strategy to enhance ZVI reactivity with minimal extra cost and complexity under aerobic conditions, but also help understand the ZVI behavior in practical applications.
研究领域:
环境科学
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污染治理
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DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
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2020
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IF 4.032
Wenhuan Wang,Lin Sang,Qingbo Guan,Yiping Zhao,Zhiyong Wei,Yang Li
Biodegradable polyesters with X-ray visibility for biomedical applications have attracted increasing attention. We herein reported a facile method of end-chain functionalization to prepare highly branched linear-comb poly (lactic acid) (Lc-PLA) using triiodobenzoic acid (TIBA) as end-capping and X-ray contrast agent. Three branch lengths of iodinated linear-comb poly (lactic acid) (I-Lc-PLA 30k , I-Lc-PLA 50k , and I-Lc-PLA 70k ) were successfully synthesized and then microspheres with well-controlled size (average size ~180 μm) were prepared. By micro-CT testing, the results showed that shorter branch length of PLA contributed more iodinated end-group functionalized sites, leading a relatively high iodine content and excellent radiopacity. After terminated with TIBA, glass transition temperature and thermal stability of I-Lc-PLA polymers were greatly improved. During the in vitro hydrolytic degradation of three months, the molecular weight , iodine content, surface microstructure and micro-CT radiopacity of these microspheres were investigated. The degradation results showed that I-Lc-PLA 50k possessed sufficient iodine content and high household unit values, suggesting a well-maintained radiopacity of I-Lc-PLA. Therefore, this work proposed a highly branched I-Lc-PLA microspheres with promising CT-imaging capacity, which could be used as a long-term embolic material.
研究领域:
生物医学材料
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高分子化学
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放射学
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DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2017
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IF 6.065
Lingjun Meng,Shaogui Yang,Cheng Sun,Huan He,Qiming Xian,Shiyin Li,Guoxiang Wang,Limin Zhang,Dong Jiang
In this study, an electromagnetic induction electrodeless lamp (EIEL) was first introduced into UV advanced oxidation processes (AOPs) for photodegradation of Diatrizoate (DTZ), which was the most persistent iodinated X-ray contrast medium (ICM), and traditional Hg lamps were taken as references. Direct photolysis rate of DTZ under EIEL irradiation was 1.34 times as that under Hg irradiation, but the electric energy consumption was 0.87 times. In this sense, the combination of EIEL and oxidants (O 2 , H 2 O 2 and S 2 O 8 2− (PS)) was further investigated. The remarkably increased photodegradation rates were observed in UV/PS system due to primary contribution rate of SO 4 − (62.5%) based on the results of radical concentrations and second-order rate constants of DTZ with SO 4 − and OH. Inorganic ions influencing the photodegradation process were investigated. The effect of natural organic materials (NOMs) in UV/PS system was studied based on contribution ratios of light screening effect and quenching. Transformation mechanisms of DTZ in UV/PS system included deiodination, intramolecular cyclization, decarboxylation, deacetylation and deamination, which were further confirmed by frontier electron density calculations. The study indicated that UV/PS with EIEL irradiation has the potential to remove pharmaceuticals in contaminated aquatic environments.
研究领域:
环境科学
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化学工程
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水处理技术
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产品关联
DOI
PubMed
高影响因子
BMC PLANT BIOLOGY
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2021
·Vol. 21
·期 1
·1-12
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IF 4.215
Wang Yu,Zhang Wenze,Liu Weikang,Ahammed Golam Jalal,Wen Wenxu,Guo Shirong,Shu Sheng,Sun Jin
Background Despite significant limitations of growth medium reuse, a large amount of organic substrate is reused in soilless cultivation of horticultural crops in China. Arbuscular mycorrhizal fungi (AMF) can promote nutrient absorption and improve plant tolerance to biotic and abiotic stresses. However, the mechanisms governing the effects of AMF on crop growth in organic continuous cropping substrates have not been elucidated.Results In this study, we showed that the inoculation of AMF in continuous cropping substrates promoted growth and root development, and increased the root and NADP-malic enzyme (NADP-ME) activity of tomato seedlings. Root transcriptome analysis demonstrated that the plant hormone signal transduction pathway was highly enriched, and 109 genes that positively correlated with the AMF-inoculated plant phenotype were obtained by gene set enrichment analysis (GSEA), which identified 9 genes related to indole acetic acid (IAA). Importantly, the levels of endogenous IAA in tomato seedlings significantly increased after AMF inoculation. Furthermore, the application of AMF significantly increased the expression levels of NADP-ME1 and NADP-ME2, as well as the activity of NADP-ME, and enhanced the root activity of tomato seedlings in comparison to that observed without inoculation of AMF. However, these effects were blocked in plants treated with 2,3,5-triiodobenzoic acid (TIBA), a polar transport inhibitor of IAA.Conclusion sThese results suggest that IAA mediates the AMF-promoted tomato growth and expression of NADP-MEs in continuous cropping substrates. The study provides convincing evidence for the reuse of continuous cropping substrates by adding AMF as an amendment.
研究领域:
植物科学
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农业
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真菌学
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园艺学
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产品关联
DOI
PubMed
高影响因子
Toxics
·
2024
·Vol. 12
·期 5
·374
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IF 3.9
Huabin Liu,Yue Wu,Jiahui Cai,Yuting Chen,Cheng Zhou,Cece Qiao,Yuliang Wang,Song Wang
Auxins play crucial regulatory roles in plants coping with cadmium (Cd) stress. However, the regulatory mechanism by which auxins alleviate Cd toxicity in tomato seedlings remains unclear. Here, we demonstrate that exposure to Cd stress leads to dynamic changes in the auxin response in tomato roots, characterized by an initial increase followed by a subsequent weakening. Under Cd stress, tomato seedlings show primary root- and hypocotyl-growth inhibition, accompanied by the accumulation of Cd and reactive oxygen species (ROS) in the roots. The exogenous application of 1-naphthylacetic acid (NAA) does not mitigate the inhibitory effect of Cd toxicity on primary root growth, but it does significantly enhance lateral root development under Cd stress. Auxin transport inhibitors, such as 1-N-naphthylphthalamic acid (NPA) and 2,3,5-triiodobenoic acid (TIBA), aggravate the growth inhibition of primary roots caused by Cd stress. Additionally, lateral root development was inhibited by NPA. However, applying auxin synthesis inhibitors L-kynurenine (kyn) and yucasin alleviated the tomato root growth inhibition caused by Cd stress; between them, the effect of yucasin was more pronounced. Yucasin mitigates Cd toxicity in tomato seedlings by reducing Cd2+absorption and auxin accumulation, strengthening ROS scavenging, and reducing cell death in roots. These observations suggest that yucasin potentially mitigates Cd toxicity and improves the tolerance of tomato seedlings to Cd stress.
研究领域:
植物生理学
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环境毒理学
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植物应激反应
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DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2017
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IF 9.446
Hui Liu,Qing Yu,Heyun Fu,Yuqiu Wan,Xiaolei Qu,Zhaoyi Xu,Daqiang Yin,Shourong Zheng
In this study, Pt catalysts supported on zeolite templated carbon (Pt/ZTC) were prepared by in-situ chemical vapor deposition using Pt exchanged Y zeolite as the template. For comparison, Pt catalysts supported on zeolite templated carbon (ZTC) and commercial activated carbon (AC) were prepared using the impregnation method. The liquid phase catalytic hydrodeiodination of two iodinated X-ray contrast media (ICM, i.e. , diatrizoate and iopamidol) was investigated on the catalysts. The catalysts were characterized by X-ray diffraction, N 2 adsorption–desorption isotherms, scanning electron microscope, transmission electron microscopy, X-ray photoelectron spectroscopy and zeta-potential measurement. The results showed that Pt/ZTC catalysts prepared by in-situ chemical vapor deposition (CVD) under varied reaction conditions were good replicas of Y zeolite in structure. Compared with the catalysts prepared by the impregnation method, Pt/ZTC had a higher Pt dispersion and more homogeneous Pt distribution. Increasing CVD temperature resulted in Pt particle growth in Pt/ZTC. The catalytic hydrodeiodination of diatrizoate and iopamidol proceeded via a sequential deiodination pathway, and followed the Langmuir-Hinshelwood model, reflecting that the conversion of adsorbed ICM was the rate-controlling step. Additionally, more effective conversion of iopamidol was observed than that of diatrizoate on Pt/ZTC. Furthermore, Pt/ZTC prepared at higher CVD temperature exhibited lower catalytic activities for the hydrodeiodination of diatrizoate and iopamidol. Solution pH markedly impacted the catalytic ICM conversion, and enhanced hydrodeiodination was observed with the increase of pH. As for catalyst reuse, Pt/ZTC remained about 80% of initial activity after 4 reuse cycles, exhibiting much higher stability than the catalyst prepared by the impregnation method. The present findings highlighted the Pt/ZTC catalysts prepared by in-situ CVD as highly active and stable catalysts for the removal of halogenated organic pollutants by catalytic hydrogenation.
研究领域:
催化
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环境化学
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材料科学
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DOI
高影响因子
ACS Catalysis
·
2026
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IF 13.6
Shi Zhanghan,Duan Fangyu,Liu Yafei,Zhang Xianwang,Song Guoquan,Yang Xiaomeng,Ma Qianli,Zhang Zongwu,Wu Dan,Xu Chunbao,Zhang Yongsheng
Cascade catalytic upgrading of biomass-derived furanic compounds to high-value cyclopentanone (CPO) and cyclopentanol (CPL) over metal–acid bifunctional catalysts has attracted considerable attention in sustainable chemistry. However, conventional bifunctional catalysts exhibit insufficient synergistic effects, primarily due to the lack of flexibility in tuning the ratio of acidic to hydrogenative active sites. Herein, we demonstrate that halogen (Br and Cl) modification of supported Cu catalysts significantly enhances both activity and selectivity in the aqueous-phase hydrogenative rearrangement of furfuryl alcohol (FOL), achieving a CPO yield of 94.4% and a CPL yield of 94.6%, respectively. Extensive characterizations reveal that the electronegative Br and Cl adatoms effectively modulate the electronic state of Cu nanoparticles, facilitating the formation of Lewis acidic Cu + sites on the catalyst surface. Mechanistic investigations disclose that Cu + sites mediate the rearrangement of FOL to 4-hydroxy-2-cyclopentenone (4-HCP), while adjacent Cu 0 sites catalyze the hydrogenation of 4-HCP to CPO, followed by its subsequent hydrogenation to CPL. Different binding strengths between Cu and halogens (I > Br > Cl) allow the regulation of the Cu + /Cu 0 ratio on the Cu surface, which in turn provides an effective way to control the reaction pathway. The developed halogen modification strategy not only offers great potential for the upgrading of biomass-derived furanics to cyclopentane derivatives but also presents a versatile strategy for regulating the surface Lewis acidity of metal catalysts, which is crucial for metal–acid bifunctional catalysis.
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产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2024
·
IF 9.4
Hongwei He,Zhoulin Ma,Shuya Zhang,An Cai,Huan Ye,Xiaobin Fan,Wenchao Peng,Yang Li
A palladium–zinc alloy nanoparticles decorated nitrogen-doped porous carbon catalyst (PdZn 30 –NC) was synthesized and utilized for Suzuki coupling reaction. The alloying palladium (Pd) with zinc (Zn) and pore expanding are realized simultaneously. Density functional theory (DFT) calculations and experimental studies reveal that the alloying Pd with Zn can lower the energy barrier in Suzuki coupling reaction. Nitrogen adsorption–desorption measurements uncover that pore expansion caused by the zinc nitrate hexahydrate assisted calcination gives rise to the multiplication of mesopore with a pore diameter of 6 nm, which facilitates mass transfer during the reaction. As a result, the alloying Pd with Zn and pore expanding together endow PdZn 30 –NC with excellent catalytic activity. PdZn 30 –NC demonstrates exceptional catalytic activity and stability in Suzuki coupling reaction. A high biphenyl yield of 97.7 % within 40 min and stable reusability of 93.3 % yield after five reuse cycles can be achieved. This work not only offers a viable method for Suzuki coupling reaction, but also provides insights for designing new catalysts toward Suzuki coupling reaction.
研究领域:
材料化学
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催化反应
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理论计算
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产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
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IF 7.7
Jiayin Gao,Yaoyao Wang,Yuqing Yu,Mengxiang Zhu,Wen Kong,Genyan Liu,Xiaogang Luo
Catalytic reduction of p -nitrophenol is usually carried out using transition metal nanoparticles such as gold, palladium , silver , and copper, especially palladium nanoparticles (Pd NPs), which are characterized by fast reaction rate, high turnover frequency , good selectivity, and high yield. However, the aggregation and precipitation of the metals lead to the decomposition of the catalyst, which results in a significant reduction of the catalytic activity. Therefore, the preparation of homogeneous stabilized palladium nanoparticles catalysts has been widely studied. Stabilized palladium nanoparticles mainly use synthetic polymers . Cellulose microspheres , as a natural polymer material with low-cost and porous fiber network structure, are excellent carriers for stabilizing metal nanoparticles . Cellulose microspheres impregnated with palladium metal nanoparticles were carbonized to have a larger specific surface area and highly dispersed palladium nanoparticles, which exhibited excellent catalytic activity in the catalytic reduction of p -nitrophenol. In this work, the cellulose carbon-based microspheres palladium (Pd@CCM) catalysts were designed and characterized by SEM, TEM , EDS, XRD, FTIR, XPS , TGA , BET, and so on. Furthermore, the catalytic performance of Pd@CCM catalysts was investigated via p -nitrophenol reduction, which showed high catalytic activity. This catalyst also exhibited excellent catalytic performance in the Suzuki-Miyaura coupling reaction. Linking aromatic monomer and benzene through Suzuki-Miyaura coupling was presented as an effective route to obtaining biaryls , and the synthesis method is low-cost and simple. In addition, Pd@CCM showed desirable recyclability while maintaining its catalytic activity even after five recycles. This work is highly suggestive of the design and application of the heterogeneous catalyst .
研究领域:
材料科学
·
催化化学
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产品关联
DOI
PubMed
高影响因子
APPLIED ORGANOMETALLIC CHEMISTRY
·
2026
·Vol. 40
·期 4
·e70549
·
IF 4.3
Linjun Shao,Zheng Yin,Ke Long,Faliang Gou,Guiying Xing,Peng Yang,Xianman Zhang
Chitosan (CS) is a widely distributed and abundant biopolymer in nature. In this study, CS was blended with poly(methacrylic acid) (PMAA) to prepare stable chitosan composite nanofibers (CS/PMAA) via electrospinning, followed by annealing. The nanofibers were then functionalized through Schiff base reactions between CS amino groups and aldehydes and used to support palladium catalysts. Their catalytic performance was evaluated by the Heck reactions. Notably, the Pd 2+ ions anchored on the CS/PMAA nanofibers exhibited higher activity than those on the 2-pyridylimino-functionalized chitosan nanofibers (2PyCS/PMAA). In contrast, the Pd 0 species supported on the 2PyCS/PMAA nanofibers showed outstanding catalytic activity and remarkable reusability. HR-TEM was utilized to monitor the morphological changes and Pd 0 nanoparticle contents on the CS/PMAA and 2PyCS/PMAA nanofibers during reuse. Chelating interactions between the nanofibers and Pd 2+ ions were studied by FT-IR, adsorption distribution analysis, XRD, and HR-TEM. The strong nucleophilic affinity of Pd 2+ ions for the CS nanofibers was further verified by PALS. In conclusion, this work presents an effective and straightforward approach for preparing highly active and stable supported palladium catalysts.
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）