| 1. |
- Denisov, Nikita, et al.
(författare)
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Light-Induced Agglomeration of Single-Atom Platinum in Photocatalysis
- 2023
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Ingår i: Advanced Materials. - : Wiley. - 0935-9648 .- 1521-4095. ; 35:5
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Tidskriftsartikel (refereegranskat)abstract
- With recent advances in the field of single-atoms (SAs) used in photocatalysis, an unprecedented performance of atomically dispersed co-catalysts has been achieved. However, the stability and agglomeration of SA co-catalysts on the semiconductor surface may represent a critical issue in potential applications. Here, the photoinduced destabilization of Pt SAs on the benchmark photocatalyst, TiO2, is described. In aqueous solutions within illumination timescales ranging from few minutes to several hours, light-induced agglomeration of Pt SAs to ensembles (dimers, multimers) and finally nanoparticles takes place. The kinetics critically depends on the presence of sacrificial hole scavengers and the used light intensity. Density-functional theory calculations attribute the light induced destabilization of the SA Pt species to binding of surface-coordinated Pt with solution-hydrogen (adsorbed H atoms), which consequently weakens the Pt SA bonding to the TiO2 surface. Despite the gradual aggregation of Pt SAs into surface clusters and their overall reduction to metallic state, which involves >90% of Pt SAs, the overall photocatalytic H2 evolution remains virtually unaffected.
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| 2. |
- Gao, Qingwei, et al.
(författare)
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Preliminary study on mechanism of confined mass transfer and separation : "secondary confinement" effect of interfacial adsorption layer [限域传质分离机制初探:界面吸附层的"二次限域"效应]
- 2020
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Ingår i: Huagong Xuebao/CIESC Journal. - : Materials China. - 0438-1157. ; 71:10, s. 4688-4695
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Tidskriftsartikel (refereegranskat)abstract
- The confined mass transfer separation membrane is mainly for the high-precision separation process at the molecular/ion level, which is of great significance to solve the application needs of CO2 separation, azeotrope separation, lithium extraction from salt lake, desalination of seawater and so on. However, at present, the research of the confined mass transfer mechanism of this kind of membrane is lagging behind, and the theoretical models of confined mass transfer are lacking, which can no longer meet the needs of the rapid development of materials and chemical engineering. From the perspective of meso-science, the abnormal phenomenon of high flux and high selectivity of the confined mass transfer separation membrane is considered, that is, breaking through the trade-off effect, which is governed by compromise-in-competition between the selectivity mechanism and the flux mechanism. It is found that the fluid molecules will preferentially adsorb at the interface and form a stable adsorption layer. Based on this, the hypothesis of "secondary confinement" is put forward, that is, the surface induced new solid-like interface will have confinement effect on the intermediate fluid again. By comparing the pore size and the secondary confined size of the confined mass transfer separation membrane, the selective mechanism of the secondary confinement is further confirmed, and the quantitative prediction of the membrane flux and selectivity is preliminarily explored by combining the selective mechanism and the flux model, which may provide a theoretical basis for the precise construction of the limited area mass transfer membrane. © 2020, Chemical Industry Press Co., Ltd. All right reserved.
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| 3. |
- Lin, Qing, et al.
(författare)
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Mechanistic and therapeutic study of novel anti-tumor function of natural compound imperialine for treating non-small cell lung cancer
- 2020
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Ingår i: Journal of Ethnopharmacology. - : Elsevier. - 0378-8741 .- 1872-7573. ; 247
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Tidskriftsartikel (refereegranskat)abstract
- Ethnopharmacological relevance: Bulbus Fritillaria cirrhosa D. Don (BFC) is a Chinese traditional herbal medicine that has long been used as an indispensable component in herbal prescriptions for bronchopulmonary diseases due to its well-established strong anti-inflammation and pulmonary harmonizing effects. Interestingly, there are few case reports in traditional Chinese medicine available where they found it to contribute in anti-tumor therapies. Imperialine is one of the most favored active substances extracted from BFC and has been widely recognized as an anti-inflammatory agent. Aim of the study: The aim of the current work is to provide first-hand evidences both in vitro and in vivo showing that imperialine exerts anti-cancer effects against non-small cell lung cancer (NSCLC), and to explore the molecular mechanism of this anti-tumor activity. It is also necessary to examine its systemic toxicity, and to investigate how to develop strategies for feasible clinical translation of imperialine. Materials and methods: To investigate anti-NSCLC efficacy of imperialine using both in vitro and in vivo methods where A549 cell line were chosen as in vitro model NSCLC cells and A549 tumor-bearing mouse model was constructed for in vivo study. The detailed underlying anti-cancer mechanism has been systematically explored for the first time through a comprehensive set of molecular biology methods mainly including immunohistochemistry, western blot and enzyme-linked immunosorbent assays. The toxicity profile of imperialine treatments were evaluated using healthy nude mice by examining hemogram and histopathology. An imperialine-loaded liposomal drug delivery system was developed using thin film hydration method to evaluate target specific delivery. Results: The results showed that imperialine could suppress both NSCLC tumor and associated inflammation through an inflammation-cancer feedback loop in which NF-kappa B activity was dramatically inhibited by imperialine. The NSCLC-targeting liposomal system was successfully developed for targeted drug delivery. The developed platform could favorably enhance imperialine cellular uptake and in vivo accumulation at tumor sites, thus improving overall anti-tumor effect. The toxicity assays revealed imperialine treatments did not significantly disturb blood cell counts in mice or exert any significant damage to the main organs. Conclusions: Imperialine exerts anti-cancer effects against NSCLC both in vitro and in vivo, and this previously unknown function is related to NF-kappa B centered inflammation-cancer feedback loop. Imperialine mediated anticancer activity is not through cytotoxicity and exhibit robust systemic safety. Furthermore, the liposome-based system we commenced would dramatically enhance therapeutic effects of imperialine while exhibiting extremely low side effects both on cellular and in NSCLC model. This work has identified imperialine as a promising novel anti-cancer compound and offered an efficient target-delivery solution that greatly facilitate practical use of imperialine.
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| 4. |
- Zhang, Yumeng, et al.
(författare)
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Molecular insight into flow resistance of choline chloride/urea confined in ionic model nanoslits
- 2021
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Ingår i: Fluid Phase Equilibria. - : Elsevier. - 0378-3812 .- 1879-0224. ; 533
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Tidskriftsartikel (refereegranskat)abstract
- Choline chloride/urea (1:2) is the most widely used deep eutectic solvent, which has attracted much attention due to its excellent advantages of low cost, environment friendly and easy synthesis. In this work, nanofriction-based molecular dynamics simulations were performed to investigate the effect of interfacial hydrophilicity on the flow resistance of Choline chloride/urea (1:2) confined in ionic model nanoslits. Simulation results showed that the flow resistance of the choline chloride/urea system increases with the increasing interfacial hydrophilicity. Urea molecules form a preferential adsorption layer on the wall. As the interfacial hydrophilicity increases, the number of urea molecules in the interfacial adsorption layer increased, whereas the stability decreased. Unique confined spatial distributions of urea molecules greatly contribute to ionic association between choline cations and chloride anions. Furthermore, with the increase of interfacial hydrophilicity, orientation distributions of urea molecules in the adsorption layer are more orderly, then causing a decrease in the average hydrogen bond number (NHB) of urea molecules. Moreover, the more the NHB of urea molecules, the better is the stability in the interfacial adsorption layer, which in turn results in less flow resistance.
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