RSC Advances
·
2019
·Vol. 9
·期 25
·14286-14295
·
IF 3.049
Wenhui He,Yawen Wang,Caimei Fan,Yunfang Wang,Xiaochao Zhang,Jianxin Liu,Rui Li
The introduction of oxygen vacancies (OVs) on the surface of photocatalysts has already been proven to be an effective way to extend the light response to visible light and trap charge carriers, thereby promoting the photocatalytic performance. In this study, h-BN/OV-BiOCl composites were prepared using hexagonal boron nitride (h-BN) to further improve the visible-light photocatalytic activity of oxygen-vacancy-enriched bismuth oxychloride (OV-BiOCl). The composition and morphology of these materials were investigated, and the photocatalytic performance experiments showed that the introduction of h-BN could significantly improve the visible-light photocatalytic activity of OV-BiOCl, which was 1.7 and 1.4 times that of pure OV-BiOCl for the degradation of rhodamine B (RhB) and bisphenol A (BPA) when the h-BN content was 5 wt%, respectively. The role of h-BN was comprehensively investigated, and the results revealed that the presence of negatively charged h-BN could improve the separation efficiency of photoinduced electrons (e−) and holes (h+) by promoting the migration of positively charged h+ to the surface of the photocatalyst, as expected. Moreover, the oxygen vacancies in OV-BiOCl were increased in the presence of h-BN; this favored the activation of more adsorbed O2 for the oxidation of pollutants. Finally, a probable mechanism was proposed for the improved photocatalytic activity of the h-BN/OV-BiOCl composites. This study provides an insight into the roles of h-BN in oxygen-vacancy-enriched photocatalysts.
研究领域:
材料科学
·
环境科学
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DOI
PubMed
高影响因子
MedChemComm
·
2013
·Vol. 5
·期 2
·147-152
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IF 2.722
Haiqing Dong,Chunyan Dong,Wenjuan Xia,Yongyong Li,Tianbin Ren
A novel prodrug of pegylated methotrexate conjugates (PMCs) with a high drug-carrying capability and a redox sensitive drug release mechanism was reported for intracellular drug delivery. The PMC was structured in a H-shape with four molecules of anticancer drug methotrexate (MTX) linked to both ends of the PEG main chain via disulfide linkers, resulting in the conjugates with a high and constant drug loading efficiency of up to 26 wt%. The amphiphilic property of PMCs enables them to self-assemble into nanoparticles in aqueous solution, while the cleavable disulfide linkers allow the conjugated MTX to exert its therapeutic activity due to the fast cleavage of disulfide linkers when exposed to the intracellular concentration of glutathione (GSH). Cell proliferation assays performed with HepG2 cancer cells confirmed the pharmacological efficacy.
研究领域:
药理学
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癌症研究
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纳米医学
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药物递送系统
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DOI
高影响因子
Advanced Science
·
2024
·
IF 14.3
Lijiao He,Xiao Zhang,Shengwei Zhang,Yi Wang,Weichao Hu,Jie Li,Yunyi Liu,Yu Liao,Xue Peng,Jianjun Li,Haiyan Zhao,Liting Wang,Yang-Fan Lv,Chang-Jiang Hu,Shi-Ming Yang
Persistent H. pylori infection triggers the repair program of the mucosa, such as spasmolytic polypeptide-expressing metaplasia (SPEM). However, the mechanism underlying the initiation of SPEM in gastric tissues by H. pylori remains unclear. Here, an increase in telomerase reverse transcriptase (TERT) protein expression is observed in chief cells upon infection with cagA -positive H. pylori . Tert knockout significantly ameliorated H. pylori -induced SPEM and single-cell RNA sequencing demonstrated that the Wnt/β-Catenin pathway is suppressed in gastric cells with Tert knockout. Mechanism study revealed that CagA elevated TERT abundance by disrupting the interaction between TERT and its novel E3 ligase, SYVN1. Interestingly, Nitazoxanide effectively relieved SPEM via inhibition of the Wnt/β-Catenin signaling in vivo. This results clarified the mechanism underlying which CagA activated the TERT/Wnt/β-Catenin pathway, thus promoting the dedifferentiation of chief cells and the occurrence of SPEM in gastric mucosa. This highlights a molecular basis for targeting CagA-activated Wnt signaling in chief cells for the treatment of gastric precancerous lesions.
研究领域:
胃肠病学
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分子生物学
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肿瘤学
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病理学
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DOI
PubMed
高影响因子
JOURNAL OF CATALYSIS
·
2019
·
IF 7.723
Rui Chen,Changjun Yang,Quanquan Zhang,Bingguang Zhang,Kejian Deng
A new iron tetra(2,3-bis(butylthio)maleonitrile)porphyrazine (FePz(SBu) 8 ) has been synthesized, then it was loaded on H-ZSM-5 zeolite to obtain a supported biomimetic photocatalyst H-ZSM-5/FePz(SBu) 8 . Using H 2 O 2 as oxidant, the photocatalytic selective oxidation of glucose in water under visible light (λ ≥ 420 nm) irradiation was carried out in presence of H-ZSM-5/FePz(SBu) 8 . Under such conditions, the glucose can be efficiently converted into value-added chemicals such as glucaric acid, gluconic acid, arabinose, glycerol and formic acid . More importantly, in comparison with pure FePz(SBu) 8 and pure H-ZSM-5 zeolite, the H-ZSM-5/FePz(SBu) 8 exhibited a higher photocatalytic activity for glucose oxidation and the formation of glucaric acid was observed only when H-ZSM-5/FePz(SBu) 8 was used, deriving from the synergistic effect between FePz(SBu) 8 and H-ZSM-5 zeolite. Some reaction parameters of glucose oxidation catalyzed by the H-ZSM-5/FePz(SBu) 8 were discussed, such as loading amount of FePz(SBu) 8 , H 2 O 2 :glucose ratio, glucose concentration, and so on. It was demonstrated that the Soret-band of FePz(SBu) 8 contributed more to the visible light photocatalytic activity than the Q-band during the photocatalytic process. The stability of H-ZSM-5/FePz(SBu) 8 during the photocatalytic process was further evaluated by the reusability test. In addition, the generation of reactive oxygen species was determined by electron spin resonance (ESR) technology and scavenger experiments. A possible reaction pathway of glucose oxidation was also discussed.
研究领域:
化学工程
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环境科学
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DOI
高影响因子
JOURNAL OF ENZYME INHIBITION AND MEDICINAL CHEMISTRY
·
2025
·
IF 5.4
Pengtao Yuan,Xi Jiang,Xintong Ni,Xusheng Shao,Xuhong Qian,Qing Yang
Chitinase h (Chi-h) has been identified as a promising pesticide target due to its exclusive distribution in lepidopteran insects and its essential role in the moulting processes. In this study, we leverage OfChi-h from destructive agricultural pest Ostrinia furnacalis (Asian corn borer) as a model target to identify novel chitinase inhibitors. A conformational restriction approach was employed to design a series of novel OfChi-h inhibitors. Among these, compound 6a showed the highest inhibitory activity against OfChi-h, with a Ki value of 58 nM. Molecular docking analysis suggested that 6a tightly bound to three subsites (-3 to −1) of OfChi-h. The binding mode is further confirmed by the co-crystallization data of 6a with the SmChiA, a bacterial homologue of OfChi-h, at a resolution of 1.8 Å. This research presents a novel approach for the development of highly potent insect chitinase inhibitors, offering potential tools for effective pest control.
研究领域:
农药研究
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酶抑制
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结构生物学
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农业化学
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昆虫生物化学
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产品关联
DOI
PubMed
高影响因子
ACS Sustainable Chemistry & Engineering
·
2022
·
IF 9.224
Yafei Li,Shiqing Wang,Shunxin Fan,Babar Ali,Xiaocheng Lan,Tiefeng Wang
For the ethanolysis of biomass-derived furfuryl alcohol (FA) to value-added ethyl levulinate (EL), the development of an efficient solid acid catalyst is very important for industrial application with high FA concentration. Herein, a H-ZSM-5 catalyst with nano b-axis channels (NB-H-ZSM-5) was synthesized and used for the conversion of FA. Detailed catalyst characterization proved that the NB-H-ZSM-5 catalysts (Si/Al = 25∼125) with ∼70 nm b-axis channels were successfully prepared. The NB-H-ZSM-5 catalyst with Si/Al = 75 showed the highest activity. Its structural characteristics allowed for fast diffusion of reactants and products and full utilization of active sites, which endowed it with higher activity compared to commercial H-ZSM-5 (C-H-ZSM-5). Its moderate acidity effectively inhibited the polymerization of FA even at a high FA concentration of 20 wt %. The spent catalyst was easily regenerated by coke burn-off to give a good recyclability. Furthermore, based on the proposed reaction network, a method of physically mixing the NB-H-ZSM-5 (75) catalyst with a small amount of Amberlyst-15 was proposed to further increase the EL yield from 64.7 to 82.1% at an FA concentration of 6 wt %.
研究领域:
催化化学
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可再生资源化学
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材料科学
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2024
·
IF 8.1
Zhongming Zhang,Enfang Gou,Zhiying Zhao,Rui Wu,Rui Fang,Weipeng Guo,Jie Yao
Organophilic pervaporation (PV) mixed matrix membranes (MMMs) have enormous potential for organic wastewater treatment due to their environmental friendliness and high efficiency. However, developing a high-flux PV membrane remains challenging. In this work, the nanocage-like hollow ZIF-71(h) (HZIF-71(h)) polyhedral nanocrystals were synthesized by heteroepitaxial growth of a ZIF-71(h) shell and successive excavation of a ZIF-67 core. The resultant HZIF-71(h) nanocrystals were blended with poly (ether block amide) (PEBA) matrix to fabricate MMMs for phenol/water separation. Results from several characterization techniques confirmed the successful preparation and formation mechanism of HZIF-71(h). Further, a series of experiments were conducted using the composite membranes to explore the impact of filler type, filler loading, operating temperature, and feed concentration on the separation performance. The incorporation of ZIFs facilitated phenol permeation while limited water transport, thereby resulting in increased separation factor. Notably, the HZIF-71(h)/PEBA-21 MMM exhibits a higher phenol flux in comparison to ZIF-71/PEBA-21 and ZIF-67/PEBA-21 MMMs, indicating the importance of the low-resistance hollow structure. The HZIF-71(h)/PEBA-21 MMM exhibits outstanding pervaporation performance with a separation factor of 15.86 and a phenol flux of 17.32 g·m −2 ·h −1 , respectively, displaying an improvement of 41.2 % and 6.4 % compared to the PEBA/PVDF membrane. Furthermore, this composite membrane demonstrated outstanding durability during continuous testing for 84 h, implying a promising potential for phenol separation.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
HIGH PERFORMANCE POLYMERS
·
2016
·
IF 1.045
Yongzhen Wang,Yanchao Yuan,Ying Zhao,Shumei Liu,Jianqing Zhao
A halogen-free flame retardant of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide-containing H-benzimidazole (DHBI) was synthesized and subsequently used as co-curing agent of 4,4′-diamino-diphenylmethane for diglycidyl ether of bisphenol-A. The structure of DHBI was characterized by Fourier transform infrared (FTIR) spectroscopy, proton, carbon 13 and phosphorus-31 nuclear magnetic resonance, and mass spectroscopy. A series of cured epoxy resins (EPs) were prepared and their flame retardancy, thermal stability, flexibility, and dielectric properties were investigated. The resulting cured EP (EP-10) with 7.45 wt% of DHBI successfully achieved UL 94 V-0 rate with limited oxygen index of 35.6% and without dropping phenomenon. Compared with the cured pristine EP (EP-00), the glass transition temperature of EP-10 was increased by 6.9°C, accompanied with an enhancement of flexible strength by 13.1 MPa and a decrement of dielectric constant by 0.3 at the testing frequency of 1 MHz.
研究领域:
材料科学
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聚合物化学
·
消防安全工程
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产品关联
DOI
高影响因子
ENERGY & FUELS
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2024
·
IF 5.2
Ziyi Li,Li Huang,Xiaoyang Yu,Kun Huang,Wenbo Cui,Hong Zhang
The development of stable and efficient ODS catalysts for achieving room-temperature catalytic oxidation desulfurization is one of the challenges in the field of catalytic oxidation desulfurization. This work successfully synthesized and evaluated a new type of composite catalyst, Mo8/h-BN, using the wet impregnation method to investigate its desulfurization performance under various conditions. ODS tests were conducted on DBT, BT, and 4,6-DMDBT using Mo8/h-BN as the catalyst, H2O2 as the oxidant, and [BMIM]PF6 as the extractant. Characterization and testing revealed that Mo8/h-BN exhibited excellent ODS activity, converting DBT completely at 60 °C in 10 min. This study not only explored the optimal desulfurization conditions but also investigated the desulfurization performance of the catalyst at room temperature. Additionally, it is speculated that there may be an electron transfer between Mo8 and h-BN, which enhances the stability of the catalyst. Finally, possible CODS mechanisms were inferred through GC-MS and free radical trapping experiments. In conclusion, the composite catalyst Mo8/h-BN provides a new pathway for developing low-energy consumption, sustainable, cost-effective, and efficient desulfurization catalysts.
研究领域:
催化化学
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能源化学
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环境科学
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产品关联
DOI
高影响因子
CEMENT & CONCRETE COMPOSITES
·
2024
·
IF 10.8
Guangpeng He,Deyu Kong,Xiaoguang Chen,Shujing Fan,Tao Meng,Jiabin Li
In this paper, low-cost dihydrate gypsum (CaSO 4 ⋅2H 2 O) was used as calcium source together with sodium metasilicate solution to prepare calcium silicate hydrate (C-S-H) gels through a mechanochemical activation strategy by using planetary and vibrational ball-milling. The influences of the prepared C-S-H gels on hydrating and hardening properties of super-retarded cement-based materials with sucrose were investigated. The results showed that CaSO 4 ⋅2H 2 O reacted with sodium metasilicate solution under mechanochemical effect during both planetary and vibrational ball-milling, although CaSO 4 ⋅2H 2 O was just slightly dissolved in water. It was also interestingly found that the C-S-H gels can continuously form while resting for a certain time after ball-milling. Under the mechanochemical activation, the prepared C-S-H gels had complete characteristic diffusion peaks and were composed of layered, flocculent and fibrous structures. While incorporating the prepared C-S-H gels into the super-retarded cement paste with sucrose, the cement hydration was greatly accelerated and the compressive strength of the hardened cement-based materials was also effectively improved at early age as expected. Through X-ray diffraction (XRD) analysis, it was found that C-S-H gels can effectively promote the growth of CH crystals along the (001) and (101) crystal planes. The scanning electron microscopy (SEM) results supported that the C-S-H gels inhibited the refinement of ettringite (AFt) crystals in super-retarded HCP with sucrose, which was more obvious at 28 d.
研究领域:
建筑材料学
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无机材料科学
·
土木工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2012
·
IF 6.002
Xiang Li,Yi Shi,Zhoujun Wang,Yahong Zhang,Yi Tang
In this paper, uniform H-β nanozeolite microsphere (β-ZMS) prepared by polymerization-induced colloid aggregation, combined with an immobilized lipase B from Candida antarctica (commercially available Novozym® 435), is applied as a racemization catalyst to the one-pot dynamic kinetic resolution (DKR) of aromatic sec -alcohols. The DKRs of various aromatic sec- alcohols can be carried out with high selectivity and conversion under optimum conditions. Importantly, it is found that, compared to commercial zeolites β (C-β), β-ZMSs display high selectivity for small sec- alcohol molecules because their shorter microporous channels reduce the diffusion time of substrate/product in the three-dimensional framework, and thereby decrease the possibility of secondary reactions. However, the β-ZMSs show a high racemization rate in the DKR of large sec- alcohol molecules, such as racemic 1-(1-naphthyl)-ethanol, thanks to their abundant accessible active sites. This observation will not only benefit the performance of acidic zeolite catalysts in one-pot DKR systems but also provide a new perspective on the application of nanozeolites in catalysis.
研究领域:
催化化学
·
生物化学
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产品关联
DOI
高影响因子
Chemical Engineering Journal Advances
·
2020
·
IF 0
Jiuhu Zhao,Zhengzhong Wen,Rongshu Zhu,Zhi Li,Ran Ding,Yongji Zhu,Tingkun Gu,Rong Yang,Zhenye Zhu
In this paper, In-metal oxide/H-Beta catalysts were synthesized by ion exchange method and In-Co 3 O 4 /H-Beta exhibited the highest catalytic activity for the selective catalytic reduction of NO x with CH 4 in presence of H 2 O and SO 2 . Thus, the synthesis conditions of In-Co 3 O 4 /H-Beta were optimized. The results showed that In-Co 3 O 4 /H-Beta exhibited excellent catalytic performance and high CH 4 selectively when the synthesis was carried out by ion exchange method, the ratio of Si and Al in H-Beta was 25, the ratio of Co 3 O 4 and H-Beta was 5:40, the concentration of ion exchange liquid was 0.033 M and calcination temperature was 500 °C. The NO x removal efficiency was about 87.6 % and N 2 selectivity could reach 96.3% in the presence of H 2 O and SO 2 . Through a series of characterizations, it was concluded that In-Co 3 O 4 /H-Beta owned stable catalyst structure, abundant Brønsted acid sites and the highest ratio of InO + /In 2 O 3 under the optimal synthesis conditions. In addition, the doped of Co 3 O 4 could inhibit the adsorption of sulfate species on the surface of In/H-Beta catalyst, leading to the excellent H 2 O and SO 2 resistance property.
研究领域:
环境科学
·
催化化学
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DOI
危险品化学品经营许可证（带存储）