Catalysis Science & Technology
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2021
·Vol. 11
·期 6
·2094-2102
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IF 6.119
Zhiqiang Chen,Suyao Liu,Huaike Zhang,Peng He,Jie Ren,Xiaodong Wen,Yong-Wang Li
The location of Brønsted acid sites in zeolites has been recognized as an important factor in acid-catalyzed reactions. In this work, two beta zeolites with different Brønsted acid site distributions are successfully synthesized by tuning the charge balance between the (Si–O–Al)− and TEA+ (Na+). There is no considerable change in crystallinity, textural properties, morphology and framework silicon/aluminum ratio. However, 27Al 2D 3Q MAS NMR experiments and infrared measurements (Py-IR and Me3Py-IR) reveal the different distributions of framework aluminum and Brønsted acid sites, respectively. For the conversion of n-dodecane, the location of Brønsted acid sites imposes a significant impact on the selectivity towards the skeletal rearrangement and β-scission of carbenium ions. The catalyst Pt/beta with a larger concentration of Brønsted acid sites in the 0.66 × 0.67 nm channels demonstrates lower catalytic activity but higher isomerization selectivity. However, the Pt/beta-N catalyst with more Brønsted acid sites in the 0.56 × 0.56 nm channels exhibits higher catalytic activity and higher cracking selectivity.
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CHEMOSPHERE
·
2020
·
IF 5.778
Jiuhu Zhao,Gaige Zhang,Jiansheng He,Zhengzhong Wen,Zhi Li,Tingkun Gu,Ran Ding,Yongji Zhu,Rongshu Zhu
In/H-Beta catalyst was prepared by optimizing the support, concentration of ion exchange liquid and calcination temperature to investigate the effects of synthesis conditions on catalytic activity of selective catalytic reduction of NO x with CH 4 . The results showed that the In/H-Beta catalyst exhibited the superior activity when concentration of exchange liquid was 0.033 M and calcination temperature was 500 °C, the NO x removal ratio could reach 97.6%. In addition, reaction conditions could affect the catalytic performance. When O 2 concentration was 10%, CH 4 :NO ratio was no less than one, space velocity was lower than 23600 h −1 and NO initial concentration was no more than 700 ppm, In/H-Beta could exhibit superior catalytic activity. Moreover, the catalytic performances of In/H-Beta catalysts were discussed after enduring H 2 O or/and SO 2 . This novel strategy could open the door for selective catalytic reduction of NO x with CH 4 .
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Catalysis Science & Technology
·
2017
·Vol. 7
·期 24
·6050-6058
·
IF 5.773
Wei Zhang,Wei Hou,Tongsuo Meng,Wenxia Zhuang,Jingyan Xie,Yu Zhou,Jun Wang
Vanadium (V)-containing all-silica beta-zeolites (VSi-Beta) were directly synthesized using a dry-gel-conversion route, in which the gel was prepared from the acid-catalysed co-hydrolysis of a silica precursor and ammonium metavanadate. Besides the framework isolated V species, VSi-Beta contained tetrahedral [V2O7]4− and (VO3)nn− species that were bonded to the framework with a high dispersion. These V species resisted the over-oxidation of fructose and efficiently catalyzed the oxidation of 5-hydroxymethylfurfural (HMF) into 2,5-diformylfuran (DFF). As a result, VSi-Beta demonstrated high activity in the one-pot and one-step conversion of fructose into DFF using atmospheric oxygen (O2) in the presence of sulfuric acid, affording a high yield of 86.3% and a maximum turnover number (TON) of 270. The catalyst can be easily recovered by filtration and exhibits good reusability. Various other carbohydrates (glucose, sucrose, inulin, raffinose, maltose and starch) were also effectively converted into DFF using VSi-Beta.
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JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Yan Chen,Guojun Lv,Xuyang Zou,Shihao Su,Jiangzhang Wang,Chaoyi Zhou,Jialing Shen,Yangbin Shen,Zhongmin Liu
Dealuminated Beta zeolite has a large amount of silanol defects on its interface, which provides an ideal place for embedding metal species and creating metal active sites in a confined microenvironment. The confined metal sites as well as their surroundings are closely related to the reactant activation and transient state achievement. Hence, unraveling the confined metal sites is of great significance for the catalytic reaction process. Herein, niobium species were incorporated into the silanol defects over dealuminated Beta zeolite with a facile dry impregnation method, co-grinding the niobium precursor with dealuminated Beta zeolite support. The successful incorporation of niobium into the silanol defects for 30Nb-Beta zeolite was verified by DRIFT, 1 H MAS NMR, UV–Vis and UV-Raman characterizations. XAS characterization and DFT calculations further disclosed that the confined Nb species existed as (SiO) 2 Nb(OH)(=O), containing two Si−O−Nb bonds, one Nb=O bond as well as one Nb−OH bond. The synthesized 30Nb-Beta zeolite catalyst displayed a superior cyclohexene conversion of 51.1%, cyclohexene oxide selectivity of 83.1% as well as TOF value of 188.2 h −1 ascribed to the inherent electrophilicity of Nb(V) for confined (SiO) 2 Nb(OH)(=O) species as well as the low oxygen transfer energy barrier for Nb V −OOH species. Furthermore, the prepared 30Nb-Beta zeolite can be effectively employed to other cyclic alkene epoxidation reactions.
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ENVIRONMENTAL RESEARCH
·
2024
·
IF 7.7
Meng Xia,Kaihao Xu,Shuai Zhang,Chengxue Zhang,Xiaocong Wang,Jiqun Li
Pyrolysis technique is considered to have great potential in the remediation of petroleum-contaminated soil, but it still has difficulties such as high energy consumption for the degradation of complex petroleum hydrocarbons and the deterioration of soil quality after treatment. In this study, the low-temperature rapid catalytic pyrolysis was realized using Beta zeolite to assist in remediating weathered petroleum-contaminated saline-alkali soil. Under the action of Beta zeolite, the removal efficiency of petroleum hydrocarbons reached 81% after pyrolysis treatment for 10 min at 250 °C, which was reduced to regulatory standard. The pyrolysis behavior and mechanism revealed that the addition of Beta zeolite effectively reduced the activation energy of C-C and C-O bonds cleavage in petroleum hydrocarbon macromolecules due to the strong acidity of Beta, meanwhile the quality of recovered oil from pyrolysis was improved. Additionally, the analyses of soil physicochemical property indicated that the harmless graphitic C generated from the degradation of petroleum hydrocarbons increased the organic matter in the soil, and the addition of Beta zeolite enhanced soil water retention capacity and reduced the soil alkalinity, thus improving the ecological function of saline-alkali soil. This study provides a new strategy for the removal of organic pollutants under special soil media conditions.
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INTERNATIONAL JOURNAL OF DAIRY TECHNOLOGY
·
2024
·
IF 2.5
Shujie Cheng,Shimin Wu,Jianqiang Lan
Polycyclic aromatic hydrocarbons (PAHs) generated from heating butter pose a potential threat to consumer health. This study involved heating butter under different conditions and analysing the changes in the content of 54 PAHs. Furthermore, we investigated the inhibitory effects of β-carotene, pure astaxanthin and astaxanthin microcapsule powder on PAH formation. Results showed that heating temperature and duration affect the formation and transformation of PAHs, with higher temperatures facilitating the synthesis of oxygenated PAHs, whereas longer heating times promote the accumulation of light PAHs. Despite an observed increase in the concentration of light PAHs following heat treatment with added antioxidants, the antioxidants significantly reduced the toxic equivalency quotients (TEQs) in butter. This study revealed the PAH production pattern during butter heating and the effectiveness of antioxidants in inhibiting their accumulation.
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FOOD CHEMISTRY
·
2025
·
IF 9.8
Fang Li,Haina Hou,Tian Zhao,Gongshuai Song,Danli Wang,Tinglan Yuan,Ling Li,Jinyan Gong
Several studies have shown that the protein-chlorogenic acid covalent complex has better function and stability than the non-covalent. The degree of binding between the proteins and chlorogenic acids (CQA) can be enhanced by the ultrasound process. Herein, the effects of ultrasound-assisted non-enzymatic covalent binding (the free radical induction (Vc)-ultrasound combination and the alkali treatment (Alkali)-ultrasound combination) of two chlorogenic acids (neochlorogenic acid (3-CQA), cryptochlorogenic acid (4-CQA)) and β-lactoglobulin (β-LG) on proteins structure and properties were investigated. Results showed that ULG-Alkali-4CQA exhibited a 5.1 % reduction in α-helices, a 6.8 % increase in random curl and proteins structures becoming loose and disordered. The hydrophilicity and thermal stability of β-LG were effectively enhanced by the addition of 4-CQA and the effect of alkali treatment-ultrasound combination. Curcumin (CUR) and lycopene (LYC) were successfully delivered by the covalent complexes as delivery vehicles. The encapsulation efficiencies of the ULG-Vc/Alkali-4CQA + CUR and ULG-Vc/Alkali-4CQA + LYC complexes were 82.81 %, 84.16 %, 89.56 % and 90.51 %, respectively. The stabilities of CUR and LYC in the ULG-Vc/Alkali-4CQA + CUR/LYC ternary complexes were superior to those of all the measured complexes delivery systems. The study hopes to establish a theoretical foundation and serve as a reference for the advancement of a highly stable food-grade delivery system.
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JOURNAL OF ENVIRONMENTAL MANAGEMENT
·
2025
·
IF 8.4
Ze Deng,Jiajia Cheng,Yaqi Zhang,Yue Zhao,Zimin Wei,Caihong Song
The composting of livestock manure produces a significant amount of hydrogen sulfide (H 2 S), which can cause environmental pollution. This has become a substantial impediment to the advancement of the composting industry. In this study, Cystathionine gamma-lyase (CSE) and Cystathionine beta-synthase (CBS) enzymes were explored from the perspective of endogenous H 2 S production. This study investigated aminooxyacetic acid (AOAA) and DL-propargylglycine (PAG) as enzyme inhibitors in composting to assess the feasibility and effectiveness of H 2 S emission reduction from chicken and swine manure. The results showed that the treatment groups reduced the cumulative H 2 S emissions by a minimum of 33.52% and a maximum of 72.11%. The CSE and CBS-mediated H 2 S production reaction was inhibited by AOAA and PAG, which resulted in a significant reduction ( P < 0.05) in H 2 S emission during composting and a considerable decrease in the loss of sulfur components in gaseous form. Furthermore, the addition of AOAA and PAG affected the genes related to organic sulfur metabolism and the sulfur metabolism cycle network. This study is the first to investigate the addition of two enzyme inhibitors in composting, examining the mechanisms at different levels. These results provide new insights into the compost management strategies for the reduction of H 2 S emissions. This is a crucial area of research for the reduction of environmental pollution and the advancement of the composting industry.
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Biomaterials Science
·
2022
·Vol. 10
·期 7
·1697-1712
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IF 7.59
Yunfei Mo,Fujian Zhao,Zefeng Lin,Xiaodong Cao,Dafu Chen,Xiaofeng Chen
The bone immune response dominated by macrophages plays an indispensable role in the osteogenesis of bone defects. Moreover, moderate polarization of macrophages against inflammatory M2 has been proved to promote osteogenesis. Therefore, the addition of anti-inflammatory agents to bioactive bone repair materials facilitates efficient bone regeneration by regulating the polarization of macrophages. Bioactive glass (BG) has been widely used for bone defect repair. However, BG alone cannot effectively inhibit the inflammatory response caused by in vivo biomaterial implantation, and finally cannot achieve satisfactory bone repair effect. Herein, the design of mesoporous bioactive glass nanoparticles (MBG) modified with β-cyclodextrin (CD-MBG) is reported. Our research shows that the anti-inflammatory drug naringin (NG) is loaded into CD-MBG (NG@CD-MBG), which achieves a sustained release within 6 days. In vitro studies reveal that NG@CD-MBG promotes better transformation of macrophages to the M2 phenotype than MBG inhibiting macrophage inflammatory responses, while the induced local immune microenvironment synergistically facilitates osteogenesis and inhibits osteoclastogenesis. Furthermore, in vivo high expression of osteogenesis-related genes in the microenvironment stimulated by NG@CD-MBG significantly promotes new bone formation in the femoral defect model of rats. The results indicate that the combination of MBG and NG has a synergistic effect on immunomodulating osteogenesis and osteoclastogenesis, providing a novel idea for the development of bone biomaterials with favorable bone immunomodulatory properties.
研究领域:
生物材料
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骨组织工程
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免疫学
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CHEMICAL ENGINEERING JOURNAL
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2026
·
IF 12.5
Shaoxia Guo,Mengting Li,Liang Gao,Yongrui Wang,Cheng Gu,Longxiao Yang,Yuping Huang,Enhui Xing,Yibin Luo,Xinbin Ma,Xingtian Shu
A series of heterogeneous Pd-catalysts was prepared via a facile new method. • Use of zeolite on EMC in C 2 mixture greatly reduced the corrosiveness of system. • The H-Beta zeolite catalyst with SiO 2 /Al 2 O 3 ratio of 22 showed superior performance. • The cooperation of H-Beta and trace MSA in presence of H 2 O boosted C 2 H 4 conversion. • A possible reaction mechanism was proposed for heterogeneous Pd-based system. Ethylene methoxycarbonylation (EMC) is highly efficient route for converting ethylene to methyl propionate (MP) with 100% atom economy, which has been commercialized over homogeneous Pd-based catalyst in pure ethylene. However, concerns about severe corrosiveness of strong liquid acids have always existed. Herein, H-Beta zeolite for the first time was introduced to cooperate with trace methanesulfonic acid (MSA) in the presence of water, to catalyze EMC in C 2 mixture. Over WMB-22 catalyst (containing H-Beta zeolite with SiO 2 /Al 2 O 3 ratio of 22, 0.32 wt% H 2 O, 0.005 wt% MSA, palladium/1,2-bis(di- tert -butylphosphinomethyl) benzene (d t bpx) complex with Pd/d t bpx/MSA ratio of 1/2/0.5), a superior ethylene conversion of 97.9% and 100% product selectivity, were obtained with C 2 H 6 /C 2 H 4 /CO feeding ratio of 1/2/2. A good linear correlation between C 2 H 4 conversions and the total acid content of H-Beta zeolite and MSA revealed that the synergistic effect between H-Beta zeolite and MSA could enhance C 2 H 4 conversion. Compared with the homogeneous catalyst with Pd/d t bpx/MSA of 1/2/15, under similar C 2 H 4 conversion conditions, the MSA amount of heterogeneous system was 1/30 of homogeneous system, indicating the addition of zeolite could greatly reduce the corrosiveness of system. 31 P nuclear magnetic resonance (NMR) results indicated that the introduction of zeolite, water and MSA could promote the generation and stabilization of active species. 1 H magic angle spinning (MAS) NMR and isotope D-tracing experiments clarified the interaction among Brønsted acid of zeolite, water and methanol, confirming the proposed mechanism pathways. This work provides a facile new method for using H-Beta zeolite and MSA as potential high-performance acid promoters for EMC. Download: Download high-res image (136KB) Download: Download full-size image
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Food Bioscience
·
2025
·
IF 5.9
Lingling Bai,Yurui Wu,Huijin Xu,Jiyuan Yang,Yiting Lu,Wenge Yang,Yonghong Hu
In this study, K-carrageenan (KC)/poly(lactic acid) (PLA) composite nanofiber membranes loaded with vitamin C (VC)/2-hydroxypropyl-β-cyclodextrin (HP-β-CD) inclusion complexes were prepared by electrostatic spinning for blueberry preservation. A scanning electron microscope, electronic universal testing machine, and other instruments were used to analyze the apparent and mechanical properties of the membrane as well as the physicochemical indexes of blueberries during the preservation process. The loading of the inclusion raised the average diameter of the nanofibers membrane, reduced the crystallinity, and hydrophobicity, and improved the thermal stability of the fibers membrane. The release curves showed that encapsulating the inclusion complex in KC/PLA significantly prolonged the release time of VC. The membranes exhibited better antimicrobial properties as well as higher antioxidant properties in vitro and in vivo . These results indicate that the developed antimicrobial membrane has good application prospects in food packaging.
研究领域:
食品科学
·
材料科学
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JOURNAL OF INORGANIC BIOCHEMISTRY
·
2020
·
IF 3.212
Zhijun He,Menghuan Wang,Qionghui Zhao,Xiaoqian Li,Pengan Liu,Bingyu Ren,Chong Wu,Xiubo Du,Nan Li,Qiong Liu
Neuronal apoptosis caused by amyloid-beta (Aβ) overproduction is one of the most important pathological features in Alzheimer's disease (AD). Endoplasmic reticulum (ER) stress induced by Aβ overload plays a critical role in this process. Bis(ethylmaltolato)oxidovanadium (IV) (BEOV), a vanadium compound which had been regarded as peroxisome proliferator-activated receptor γ (PPARγ) agonist, was reported to exert an antagonistic effect on ER stress. In this study, we tested whether BEOV could ameliorate the Aβ-induced neuronal apoptosis by inhibiting ER stress. It was observed that BEOV treatment ameliorated both tunicamycin-induced and/or Aβ-induced ER stress and neurotoxicity in a dose-dependent manner through downgrading ER stress-associated and apoptosis-associated proteins in primary hippocampal neurons. Consistent with in vitro results, BEOV also reduced ER stress and inhibited neuronal apoptosis in hippocampi and cortexes of transgenic AD model mice. Moreover, by adopting GW9662 and salubrinal , the inhibitor of PPARγ and hyperphosphorylated eukaryotic translation initiation factor 2α, respectively, we further confirmed that BEOV alleviated Aβ–induced ER stress and neuronal apoptosis in primary hippocampal neurons by activating PPARγ. Taken together, these results provided scientific evidences to support the concept that BEOV ameliorates Aβ–induced ER stress and neuronal apoptosis through activating PPARγ.
研究领域:
神经科学
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药理学
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分子生物学
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