CATALYSIS TODAY
·
2019
·
IF 4.888
Yiquan Xie,Ling Zhang,Yiwen Jiang,Shichao Han,Liang Wang,Xiangju Meng,Feng-Shou Xiao
Catalytic combustion of CH 4 to CO 2 and H 2 O was studied over zeolite-supported Pd catalysts, and it was found that zeolite-supported Pd catalysts can present pronounced discrepancy in the catalytic performance of methane oxidation when Na-ZSM-5 was ion-exchanged with various cations of La, Ni, and Mg. Very interestingly, the Pd catalyst supported by NaLa-ZSM-5 exhibited the best result. Over an optimized catalyst, a complete conversion of methane can be achieved at around 320 °C, which is about 60 °C lower than the temperature needed for Pd/Na-ZSM-5. Physicochemical characterizations such as XRD, SEM, HRTEM, XPS, and ICP-OES techniques were used to investigate the factors influencing the catalytic activity and find out the reasons behind the discrepancy in the catalytic performance of methane combustion over these zeolite-supported Pd catalysts. Based on the characterization results, it is proposed that the Pd dispersion and its chemical states are major factors that govern catalytic performance of methane combustion over these catalysts. To the best of our knowledge, the optimal catalyst in this study stands out compared with other reported similar Pd catalysts for the catalytic combustion of methane in terms of activity.
研究领域:
化学工程
·
催化科学
✓ 已验证
DOI
高影响因子
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
·
2021
·
IF 6.064
Xiaoling Qu,Guangyuan Zhou,Rui Wang,Haiyan Zhang,Zhipeng Wang,Min Jiang,Jun Tang
In pursuit of poly(ethylene 2,5-furandicarboxylate) PEF materials with high molecular weight, satisfactory appearance and faster crystallization rate, its preparation from dimethyl furan-2,5-dicarboxylate (DMFD) with ethylene glycol (EG) in the trace presence of metal zinc was performed via transesterification method. Optimization of the main polymerization parameters enabled Zn-catalyzed PEF to gain high molecular weight ( M n , 5.40 × 10 4 g mol −1 ) and low content of diethylene glycol furandicarboxylate unit (DEGF, 2.91%). On the basis of experimental phenomena and high performance liquid chromatography (HPLC), the actual catalytic active species of metal zinc in the polymerization was speculated to be a salt of 2, 5-furandicarboxylate derivative (Zn(II)). The in-stiu catalyst can efficaciously inhibit the influence of by-product FDCA on the color of PEF, which displayed quite better appearance (close to white). Differential Scanning Calorimetry (DSC) showed that the in-stiu catalytic system acted as nucleating agent (NA) and the crystallization half-time (t 1/2 ) of PEFs-Zn was only 1/4 of that of PEF-tin. Additionally, series of high molecular weight furan-based polyesters from DMFD and diols with different methylene (3, 5, 6 and 8) were obtained by zinc powder as in-stiu catalyst, which further evidenced it to be efficiency and universality.
研究领域:
材料科学
·
聚合物化学
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL RESEARCH
·
2023
·
IF 8.3
Ni-Hong Yao,Ya-Nan Du,Jia-Xi Xiong,Ying Xiao,Hang-Hang He,Ze-Feng Xie,Duo Huang,Qi Song,Jing Chen,Dazhong Yan,Hong-Jun Chao
The compound 3,5-xylenol is an essential precursor used in pesticides and industrial intermediate in the disinfectants and preservatives industry. Its widespread application makes it an important source of pollution. Microbial bioremediation is more environmentally friendly than the physicochemical treatment process for removing alkylphenols from a polluted environment. However, the 3,5-xylenol-degrading bacteria is unavailable, and its degradation mechanism remains unclear. Here, a 3,5-xylenol-metabolizing bacterial strain, designated Rhodococcus sp. CHJ602, was isolated using 3,5-xylenol as the sole source of carbon and energy from a wastewater treatment factory. Results showed that strain CHJ602 maintained a high 3,5-xylenol-degrading performance under the conditions of 30.15 °C and pH 7.37. The pathway involved in 3,5-xylenol degradation by strain CHJ602 must be induced by 3,5-xylenol. Based on the identification of intermediate metabolites and enzyme activities , this bacterium could oxidize 3,5-xylenol by a novel metabolic pathway. One methyl oxidation converted 3,5-xylenol to 3-hydroxymethyl-5-methylphenol, 3-hydroxy-5-methyl benzaldehyde, and 3-hydroxy-5-methylbenzoate. After that, another methyl oxidation is converted to 5-hydroxyisophthalicate, which is metabolized by the protocatechuate pathway. It is catalyzed by a series of enzymes in strain CHJ602. In addition, toxicity bioassay result indicates that 3,5-xylenol is toxic to zebrafish and Rhodococcus sp. CHJ602 could eliminate 3,5-xylenol in water to protect zebrafish from its toxicity. The results provide insights into the bioremediation of wastewater contaminated 3,5-xylenol.
研究领域:
环境科学
·
微生物学
✓ 已验证
DOI
PubMed
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 49
·38810-38817
·
IF 3.84
Yeping Li,Jingbo Xu,Yun Xu,Liying Huang,Junli Wang,Xiaonong Cheng
The objective of the study is to describe a new approach of combining quantum dots into chitosan as an anti-cancer drug carrier. Novel chitosan–ZnSe/ZnS (CS–ZnSe/ZnS) nanoparticles were synthesized by a one-step ionic gelation technique, with ZnSe/ZnS quantum dots (ZnSe/ZnS QDs) as cross-linking agent and for fluorescent labeling. The approach not only avoids the use of emulsifiers and chemical cross-linking agents but also prevents the possibility of damage to drugs. The fluorescent CS–ZnSe/ZnS nanoparticles were about 100–500 nm in size and stable in a physiological environment. Low cytotoxicity was ensured by investigation with mouse lung carcinoma cells. The cell viability remained 99% when the concentration of CS–ZnSe/ZnS nanoparticles increased to 200 μg mL−1. In the in vitro drug release experiment, 5-fluorouracil (5-Fu) loaded within CS–ZnSe/ZnS nanoparticles had more preferable sustained-release performance and longer equilibrium time compared with that of the pure 5-Fu. The fluorescent CS–ZnSe/ZnS nanoparticles are expected to be used for biological fluorescent labeling and drug carriers.
研究领域:
生物材料学
·
纳米医学
·
药剂学
✓ 已验证
DOI
高影响因子
FLUID PHASE EQUILIBRIA
·
2019
·
IF 2.514
Xianming Zhang,Yufeng Hu,Weiting Ma,Jianguang Qi,Shuqin Mo
The salt effect on vapor–liquid phase equilibrium (VLE) has potential applications in industrial production of 1,3,5-trioxane. Optimizing reactive distillation process and developing new catalysts for industrial production of 1,3,5-trioxane require a reliable model for VLE of the reaction mixtures. Here an extended UNIFAC model combined a Debye–Hückel type is developed to describe the vapor–liquid and chemical equilibria of the multi-solvent salt-containing reactive mixtures associated with the 1,3,5-trioxane synthesis. New experimental data for the VLE of the quinary systems (formaldehyde + 1,3,5-trioxane + methanol + salt + water) and their ternary subsystems (1,3,5-trioxane + salt + water), (methanol + salt + water), and (formaldehyde + salt + water) are systematically measured at atmospheric pressure. The salts considered include LiCl, NaCl, KCl, NaBr, MgSO 4 , MgCl 2 , and Na 2 SO 4 . The model parameters, which are either obtained from the literature or determined from the VLE data of the above-mentioned ternary systems , are used to provide predictions for the quinary systems (formaldehyde + 1,3,5-trioxane + methanol + salt + water). The agreements between measured and predicted results are accurate. Furthermore, the model is used to uncover the effects of the salts considered on the VLE of these chemical reactive systems. The results show that MgSO 4 is a potential additive that can be used to improve the vapor–liquid phase separation during the reactive distillation process of 1,3,5-trioxane production.
研究领域:
化学工程
·
物理化学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2021
·
IF 6.707
Baocheng Qiu,Yakun Zhang,Yi Liu,Yi Zhang
The efficient conversion of ethane has become more attractive recently because of the shale gas revolution. Platinum-based catalyst is the most active for direct dehydrogenation of ethane to ethylene, but it always suffers deactivation due to coke deposition and sintering of supported Pt. We have successfully synthesized a Pt-embedded inside HZSM-5 crystal catalyst (Pt@HZSM-5) by hydrothermal synthesis using Pt/SiO 2 as only silicone source, to realize excellent stability during the dehydrogenation of ethane (EDH) to ethylene. Based on various characterization results, including in-situ synchrotron XANES and EXAFS, in situ XPS, operando DRIFTS, as well as 27 Al MAS NMR, the stable Pt species with high electron density on Pt@HZSM-5 avoids the deep dehydrogenation of ethane to form coke, and the surrounding environment of Pt active phase, including newly formed HZSM-5 frameworks and its acidity, contributes to suppressing the aromatization of the formed ethylene. As synergic effects, the Pt@HZSM-5 catalyst realizes excellent stability during 50 h EDH reaction without any regenerations with relatively high ethane conversion under the serve reaction conditions (90% ethane in feed gas, 0.1 MPa, 550 °C). However, the conventional Pt/HZSM-5 catalyst exhibits dynamic transformation of Pt chemical state, particle size, and its surrounding environment, resulting in rapid deactivation induced by much more carbon deposition and aromatization of the formed ethylene.
研究领域:
催化化学
·
材料科学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 57
·51591-51597
·
IF 3.289
Dongdong Lu,Fangyuan Gai,Zhen-An Qiao,Xue Wang,Tao Wang,Yunling Liu,Qisheng Huo
This work demonstrated that a series of ultrabright fluorescent silica nanoparticles have been synthesized and designed via the reverse microemulsion method to encapsulate (2,2′-bipyridine)2-(5-aminophenanthroline) Ru bis(hexafluorophosphate) (Rubpy-phen). Transmission electron microscopy (TEM), scanning electron microscopy (SEM), dynamic light scattering (DLS), inductively coupled plasma (ICP) and fluorescence spectra were used to study the morphology and properties of the nanoparticles. By introducing ethanol into the reaction system, the obtained uniform fluorescent nanoparticles showed monodispersity and controllable size. With an increase of nanoparticle size (from 50–180 nm), the relative brightness of the nanoparticles was greatly improved from 534 to 86 972 by comparison with free dye molecules. Due to the protection of the silica matrix, the fluorescence of high concentration dye-doped silica nanoparticles (Rubpy-phen NPs) is not quenched, which results in higher fluorescence intensity and relative brightness. Moreover, the silica matrix can also protect Rubpy-phen from leakage. Due to the high brightness and biocompatibility, Rubpy-phen NPs have potential applications in the biological field.
研究领域:
材料科学
·
生物学
·
纳米医学
✓ 已验证
DOI
高影响因子
Journal of Flow Chemistry
·
2018
·Vol. 8
·期 1
·29-34
·
IF 1.658
Yu Jiangang,Xu Jianguo,Li Jie,Jin Yi,Xu Wanghui,Yu Zhiqun,Lv Yanwen
A two-step flow reactor has been set up for an expeditious synthesis of 4-benzylidene-pyrazol-5-one derivatives. This procedure involved cyclization of aromatic hydrazine/ β -keto ester and subsequent Knoevenagel condensation reaction with aromatic aldehydes in tandem without isolation of intermediates. Residence time was reduced to less than 2 min in total through conducting this reaction at a relatively high temperature. Accordingly, 15 samples were achieved and isolated in moderate to excellent yields.
ᅟ
研究领域:
有机化学
·
药物化学
✓ 已验证
DOI
高影响因子
Precision Chemistry
·
2026
·
IF 7.7
Liu Jibiao,Xia Hongjin,Zhang Zheng,Yu Zhixuan,Hu Yidong,Wu Zexian,Zhang Qiang,Li Qingyang
A zeolitic
imidazolate framework-8 film is controllably synthesized
on various substrates in 5 min through integrating zinc electrodeposition
and microwave-solvothermal treatment first, representing the cheapest
and fastest route until now. This rapid and cheap strategy opens up
a new avenue for the rational design and synthesis of metal–organic
framework films.
✓ 已验证
产品关联
DOI
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
·
2026
·
IF 5.4
Xingyu Hu,Zhiyong Li,Xiaoge Li,Xiangyan Ji,Jingjing Meng
A highly conjugated biobased liquid HPE monomer was fabricated from HMF. • The benzimidazole motif HPE contributes to a relatively mild curing behavior. • The HPE endows the resin with favorable mechanical properties and dimensional stability. • The HPE networks showed good solvent resistance and shape memory. • This strategy provided a tractable biocomposite fabrication. A novel bio-based epoxy monomer (HPE) bearing a rigid benzimidazole-furan skeleton was synthesized from 5-hydroxymethylfurfural (5-HMF). The activation energy for HPE-derived networks was relatively lower than that of the DGEBA counterparts, indicating favorable curing conditions. The cured HPE-thermosets exhibited exceptional mechanical properties. For instance, HPE/APB achieved good tensile strength (105.67 ± 13.43 MPa), flexural strength (125.43 ± 16.65 MPa), and impact strength (17.99 ± 1.10 kJ m −2 ). Moreover, the thermomechanical investigation also suggested its advantageous storage modulus of 3.55 GPa at 30 °C, which surpassed the petroleum-based DGEBA counterparts. Notably, HPE-networks displayed unique dimensional stability with a thermal expansion coefficient ranging from 87 to 115.4 ppm °C −1 below 200 °C. In contrast to DDM-cured thermoset, APB-cured networks also favored decreasing dielectric constant and loss. On the whole, the APB hardener outperformed the DDM in most cases. Furthermore, glass fiber-reinforced HPE composites demonstrated 90.8% peeling off in DMF under microwave-assisted conditions, making sustainable fiber recycling possible. This work provides a promising strategy for HMF-related renewable epoxy resins. Download: Download high-res image (147KB) Download: Download full-size image
✓ 已验证
产品关联
DOI
高影响因子
Molecular Catalysis
·
2026
·
IF 4.3
Huamei Zhong,Xiaotong Li,Tongqing Tang,Hongyu Zhu,Xuean Song,Shewei Hu,Feifei Chen,Alei Zhang,Kequan Chen
Multi-enzyme cascade designed for 5-hydroxypipecolic acid synthesis from low-cost substrate. • Self-sufficient cofactor recycling achieved without expensive exogenous coenzymes. • Under glucose-controlled feeding, the system achieved a product titer of 23.65 g L -1 . 5-Hydroxypipecolic acid (5-HPA) is a chiral building block widely employed in pharmaceutical synthesis. Conventional chemical synthesis of 5-HPA is limited by poor stereoselectivity and environmental burdens. Herein, we developed a biosynthetic method for 5-HPA production from L-lysine (L-Lys) through a multi-enzyme cascade. Firstly, a lysine 6-aminotransferase SkL6AT from Stenotrophomonas koreensis and an imine reductase HeP5C from Halomonas elongata were screened and introduced into recombinant strains capable of converting L-Lys to L-pipecolic acid (L-PA). After optimization of plasmid copy number and ribosome-binding site strength, as well as establishment of the NADH regeneration system, the L-PA titer reached 7.50 g L⁻¹. Subsequently, a hydroxylase XdPH from Xenorhabdus doucetiae was introduced to construct a 5-HPA-producing strain. Fermentation conditions were optimized in shake flasks and subsequently scaled up to a 5 L bioreactor. Under a fed-batch strategy, the final engineered strain produced 23.65 g L -1 5-HPA with a yield of 0.587 g g⁻¹ from L-Lys. Download: Download high-res image (192KB) Download: Download full-size image
✓ 已验证
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2026
·
IF 3.9
Xin-Bo Pang,Jing-Pei Cao,Nai-Yu Yao,Jing-Ping Zhao,Tian-Long Liu,Shi-Jie Cai,Xiao-Yan Zhao,Tungalagtamir Bold
Catalytic pyrolysis as an important pathway for the production of sustainable chemicals and fuels from biomass. However, it is still a huge challenge to significantly improve the yield of light aromatics by adjusting the structure of ZSM-5 zeolite and to fully understand its catalytic mechanism. Here, the directional preparation of ZSM-5 nanosheets with controllable b-axis thickness was achieved by controlling the amount of silicalite-1 added during the hydrothermal synthesis process. Characterization results demonstrate that the reduction in b-axis thickness greatly enhances the mass transfer process of the zeolite while enhancing the accessibility of acidic sites, thereby promoting the catalytic conversion of biomass pyrolysis volatiles to aromatic. The yield of light aromatic hydrocarbons in bio-oil is substantial increased, the bio-oil of 20-NCZ5 had the highest aromatic content with a yield of 97.1% and a yield of 135 mg/g, achieving efficient catalytic upgrading of bio-oil. Highly b-axis-oriented ZSM-5 nanosheets provide a new approach for efficient biomass utilization. Furthermore, this zeolite holds promise for broader applications in the catalytic conversion of various energy sources.
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）