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  • Article
    Zhang H, Lu Y, Liu H, Fang J.
    Nanoscale. 2015 Jul 21;7(27):11591-601.
    AgCl semiconductor nanocrystals (NCs) with trapezohedral (TPH) and concave hexoctahedral (HOH) structures have been successfully synthesized for the first time in high yield by a direct one-pot solvothermal method. The as-prepared TPH, concave HOH AgCl NCs with unconventional polyhedral shapes and smooth surfaces were enclosed by 24 high-index {311} facets and 48 high-index {15 5 2} facets, respectively. A specific ionic liquid poly(diallyldimethylammonium) chloride (PDDA) acted as both a Cl(-) ion precursor and a morphology-controlled stabilizer, which was indispensable for the formation of these high-index faceted AgCl polyhedra and the derived uniform octahedral AgCl in an appropriate concentration of hot AgNO3 and ethylene glycol (EG) solution. With high-index facets exposed, both TPH and concave HOH AgCl NCs exhibit much higher photocatalytic activity than octahedral AgCl NCs that have mainly {111} faces exposed, with lower surface areas and surface energies, for the degradation of organics under sunlight. It is expected that the use of polyhedral AgCl NCs with high-index facets is an effective approach for the design of alternative semiconductor photocatalysts with a high performance, which may find potential applications such as in photochromics and environmental management.
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  • Article
    Guo J, Zhu Y, Yu L, Li Y, Guo J, Cai J, Liu L, Wang Z.
    PeerJ. 2021;9:e11591.
    BACKGROUND: Ovarian cancer is the most common gynecological malignancy and is difficult to manage due to the emergence of resistance to various chemotherapeutic drugs. New efforts are urgently awaited. Aspirin, which is traditionally considered a nonsteroidal anti-inflammatory drug (NSAID), has been reported to exert potential chemopreventive effects. Therefore, we aimed to investigate the anticancer effect and explore the underlying molecular mechanisms of aspirin on epithelial ovarian cancer (EOC) cells.
    METHODS: We conducted wound healing, transwell migration, EdU cell proliferation, colony formation and apoptosis detection assays to observe the effects of aspirin on the migration, proliferation and apoptosis of EOC cells (A2870, Caov-3, and SK-OV-3). EOC cells were treated with a combination of aspirin and cisplatin (CDDP) to observe the effect of aspirin on enhancing CDDP sensitivity. Orthotopic xenograft models of ovarian cancer established with A2780-Luciferase-GFP cells were applied to compare tumor growth inhibition in the control, CDDP and CDDP plus aspirin groups through in vivo imaging, which can be used to continuously monitor tumor growth. The expression and acetylation levels of p53 in EOC cells treated with aspirin were determined using western blotting, and p53 acetylation levels were examined in tumors harvested from the transplanted mice. Quantitative real-time PCR was used to assess the mRNA expression of p53 target genes.
    RESULTS: Aspirin inhibited migration and proliferation and induced apoptosis in EOC cell lines in a concentration-dependent manner. In vitro, aspirin enhanced the sensitivity of EOC cells to CDDP by increasing its inhibitory effect on proliferation and its effect on inducing apoptosis. In vivo, the differences in the tumor growth inhibition rates among the different CDDP experimental groups were statistically significant (p < 0.05). Aspirin did not affect p53 protein expression but increased the p53 acetylation level in a concentration-dependent manner. In addition, the mRNA levels of CDKN1A, BAX, FOXF1, PUMA, and RRAD in EOC cells were significantly increased by the aspirin treatment.
    CONCLUSIONS: Aspirin inhibits tumor progression and enhances the CDDP sensitivity of EOC cells. These antitumor effects of aspirin might be mediated by p53 acetylation and subsequent activation of p53 target genes.
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  • Article
    Chuan Tan Y, Chun Zeng H.
    Chem Commun (Camb). 2016 Oct 04;52(77):11591-4.
    An aqueous one-pot self-templating synthesis method to prepare highly uniform ZIF-67 hollow spheres (ZIF-67-HS) and their transition metal-doped derivatives (M/ZIF-67-HS, M = Cu and/or Zn) was developed. Extension of this approach to another important class of MOFs (metal carboxylates; e.g., HKUST-1) and facile design of derived nanostructures with complex architectures were also achieved.
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  • Article
    Zhang C, Lin X, Zhang Z, Long LS, Wang C, Lin W.
    Chem Commun (Camb). 2014 Oct 09;50(78):11591-4.
    A novel organic-inorganic hybrid monocapped/bicapped Keggin structure [Co(II)(bpy)3]6(H2bpy)[(Co(II)bpy)2(PMo8(VI)Mo4(V)O40)]3 [(Co(II)bpy)(PMo8(VI)Mo4(V)O40)]·16H2O (bpy = 2,2'-bipyridine) was synthesized and shown to be an efficient visible light-driven catalyst for water oxidation.
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  • Article
    Chakraborty H, Haldar S, Chong PL, Kombrabail M, Krishnamoorthy G, Chattopadhyay A.
    Langmuir. 2015 Oct 27;31(42):11591-7.
    The lipid composition of archaea is unique and has been correlated with increased stability under extreme environmental conditions. In this article, we have focused on the evolution of membrane organization and dynamics with natural evolution. Dynamic anisotropy along the membrane normal (i.e., gradients of mobility, polarity, and heterogeneity) is a hallmark of fluid phase diester or diether phospholipid membranes. We monitored gradients of mobility, polarity, and heterogeneity along the membrane normal in membranes made of a representative archaeal lipid using a series of membrane depth-dependent fluorescent probes, and compared them to membranes prepared from a typical diether lipid from higher organisms (eukaryotes). Our results show that the representative dynamic anisotropy gradient along the membrane normal is absent in membranes made from archaeal lipids. We hypothesize that the dynamic gradient observed in membranes of diester and diether phospholipids is a consequence of natural evolution of membrane lipids in response to the requirement of carrying out complex cellular functions by membrane proteins.
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  • Article
    Li L, Peng Y, Yue Y, Hu Y, Liang X, Yin P, Guo L.
    Chem Commun (Camb). 2015 Jul 25;51(58):11591-4.
    Novel concave gold nanocuboids bounded by 24 high-index {611} facets are synthesized using the seed-mediated growth method via an overgrowth mechanism. The as-synthesized products demonstrated greatly enhanced catalytic activity for the electro-oxidation of glucose and the reduction of 4-nitrothiophenol (4-NTP) under a laser.
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  • Article
    Bertolin C, Cavazzani S.
    Heliyon. 2022 Nov;8(11):e11591.
    The Stave Churches (SCs) are one of the most iconic heritages in Norway, and only 28 medieval SCs have survived till our age in this country. They are built on wood with staves and wooden sleepers standing off the ground on foundation stones which have the primary purpose of guaranteeing structural support, ensuring integrity of the leveled foundation, and avoid ground water or rainwater penetration up to the valuable wooden structures. This paper aims to analyze the risk of Freeze-Thaw (F-T) decay on the foundation stones of the 28 SCs using an algorithm with a single climate input parameter i.e., the land surface temperature, extracted from the Global Land Data Assimilation System GLDAS which integrates satellite- and ground-based observational data products. The novel proposed algorithm estimates a climate-based index of F-T risk on foundation stones starting from the analysis of the variability of a 70-year (i.e., 1950 to 2020) land surface temperature datasets at these 28 locations. The outcome is further used to evaluate the average lifetime (half-life time) of foundation stones as well as the number of interventions necessary to guarantee their structural soundness thus providing a quantitative, predictive, and timely effective information to SC churches managers, and conservators on the climate change effect on foundation stones degradation at support of prioritization of maintenance interventions.
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  • Article
    Huang Y, Geng J, Wang M, Liu W, Hu H, Shi W, Li M, Huo G, Huang G, Xu A.
    Sci Rep. 2024 05 21;14(1):11591.
    Podocytes are specialized terminally differentiated cells in the glomerulus that are the primary target cells in many glomerular diseases. However, the current podocyte cell lines suffer from prolonged in vitro differentiation and limited survival time, which impede research progress. Therefore, it is necessary to establish a cell line that exhibits superior performance and characteristics. We propose a simple protocol to obtain an immortalized mouse podocyte cell (MPC) line from suckling mouse kidneys. Primary podocytes were cultured in vitro and infected with the SV40 tsA58 gene to obtain immortalized MPCs. The podocytes were characterized using Western blotting and quantitative real-time PCR. Podocyte injury was examined using the Cell Counting Kit-8 assay and flow cytometry. First, we successfully isolated an MPC line and identified 39 °C as the optimal differentiation temperature. Compared to undifferentiated MPCs, the expression of WT1 and synaptopodin was upregulated in differentiated MPCs. Second, the MPCs ceased proliferating at a nonpermissive temperature after day 4, and podocyte-specific proteins were expressed normally after at least 15 passages. Finally, podocyte injury models were induced to simulate podocyte injury in vitro. In summary, we provide a simple and popularized protocol to establish a conditionally immortalized MPC, which is a powerful tool for the study of podocytes.
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  • Article
    Fioravanti G, Lugli F, Gentili D, Mucciante V, Leonardi F, Pasquali L, Liscio A, Murgia M, Zerbetto F, Cavallini M.
    Langmuir. 2014 Oct 07;30(39):11591-8.
    The studies on surface chemical gradients are constantly gaining interest both for fundamental studies and for technological implications in materials science, nanofluidics, dewetting, and biological systems. Here we report on a new approach that is very simple and very efficient, to fabricate surface chemical gradients of alkanethiols, which combines electrochemical desorption/partial readsorption, with the withdrawal of the surface from the solution. The gradient is then stabilized by adding a complementary thiol terminated with a hydroxyl group with a chain length comparable to desorbed thiols. This procedure allows us to fabricate a chemical gradient of the wetting properties and the substrate work-function along a few centimeters with a gradient slope higher than 5°/cm. Samples were characterized by cyclic voltammetry during desorption, static contact angle, XPS analysis, and Kelvin probe. Computer simulations based on the Dissipative Particle Dynamics methods were carried out considering a water droplet on a mixed SAM surface. The results help to rationalize the composition of the chemical gradient at different position on the Au surface.
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  • Article
    Lee K, Ayyasamy MV, Ji Y, Balachandran PV.
    Sci Rep. 2022 07 08;12(1):11591.
    We demonstrate the capabilities of two model-agnostic local post-hoc model interpretability methods, namely breakDown (BD) and shapley (SHAP), to explain the predictions of a black-box classification learning model that establishes a quantitative relationship between chemical composition and multi-principal element alloys (MPEA) phase formation. We trained an ensemble of support vector machines using a dataset with 1,821 instances, 12 features with low pair-wise correlation, and seven phase labels. Feature contributions to the model prediction are computed by BD and SHAP for each composition. The resulting BD and SHAP transformed data are then used as inputs to identify similar composition groups using k-means clustering. Explanation-of-clusters by features reveal that the results from SHAP agree more closely with the literature. Visualization of compositions within a cluster using Ceteris-Paribus (CP) profile plots show the functional dependencies between the feature values and predicted response. Despite the differences between BD and SHAP in variable attribution, only minor changes were observed in the CP profile plots. Explanation-of-clusters by examples show that the clusters that share a common phase label contain similar compositions, which clarifies the similar-looking CP profile trends. Two plausible reasons are identified to describe this observation: (1) In the limits of a dataset with independent and non-interacting features, BD and SHAP show promise in recognizing MPEA composition clusters with similar phase labels. (2) There is more than one explanation for the MPEA phase formation rules with respect to the set of features considered in this work.
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  • Article
    Khukalenko IS, Kaplan-Rakowski R, An Y, Iushina VD.
    Educ Inf Technol (Dordr). 2022;27(8):11591-11613.
    High-immersion virtual reality (VR) technology is often associated with gaming. Yet, it is increasingly popular in educational contexts due to its potential to engage and motivate learners. Prior to VR technology integration in the classroom, the acceptance or resistance toward VR needs to be explored. This paper reports the results obtained from a large-scale (N = 20,876) survey on teachers' attitudes toward the use of VR for education. The survey explored the relationships between the teachers' VR integration level and their instructional approaches, as well as the frequency of VR use. Furthermore, the survey yielded answers on the relationship between the availability of information technology (IT) personnel and the frequency of VR use. Overall, teachers had moderately positive perceptions of the use of VR in education. There was no strong correlation between instructional approaches and the level of VR integration, but lower levels of VR integration were associated with more traditional teaching approaches. The results revealed a positive correlation between the level of VR integration and the frequency of VR use. However, the VR frequency use had a weak correlation with the availability of IT personnel.
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  • Article
    Xie J, Owen T, Xia K, Singh AV, Tou E, Li L, Arduini B, Li H, Wan LQ, Callahan B, Wang C.
    J Biol Chem. 2015 May 01;290(18):11591-600.
    Zinc is an essential trace element with wide-ranging biological functions, whereas the Hedgehog (Hh) signaling pathway plays crucial roles in both development and disease. Here we show that there is a mechanistic link between zinc and Hh signaling. The upstream activator of Hh signaling, the Hh ligand, originates from Hh autoprocessing, which converts the Hh precursor protein to the Hh ligand. In an in vitro Hh autoprocessing assay we show that zinc inhibits Hh autoprocessing with a Ki of 2 μm. We then demonstrate that zinc inhibits Hh autoprocessing in a cellular environment with experiments in primary rat astrocyte culture. Solution NMR reveals that zinc binds the active site residues of the Hh autoprocessing domain to inhibit autoprocessing, and isothermal titration calorimetry provided the thermodynamics of the binding. In normal physiology, zinc likely acts as a negative regulator of Hh autoprocessing and inhibits the generation of Hh ligand and Hh signaling. In many diseases, zinc deficiency and elevated level of Hh ligand co-exist, including prostate cancer, lung cancer, ovarian cancer, and autism. Our data suggest a causal relationship between zinc deficiency and the overproduction of Hh ligand.
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  • Article
    Gullberg M, Polacek C, Bøtner A, Belsham GJ.
    J Virol. 2013 Nov;87(21):11591-603.
    The foot-and-mouth disease virus (FMDV) capsid protein precursor, P1-2A, is cleaved by 3C(pro) to generate VP0, VP3, VP1, and the peptide 2A. The capsid proteins self-assemble into empty capsid particles or viruses which do not contain 2A. In a cell culture-adapted strain of FMDV (O1 Manisa [Lindholm]), three different amino acid substitutions (E83K, S134C, and K210E) were identified within the VP1 region of the P1-2A precursor compared to the field strain (wild type [wt]). Expression of the O1 Manisa P1-2A (wt or with the S134C substitution in VP1) plus 3C(pro), using a transient expression system, resulted in efficient capsid protein production and self-assembly of empty capsid particles. Removal of the 2A peptide from the capsid protein precursor had no effect on capsid protein processing or particle assembly. However, modification of E83K alone abrogated particle assembly with no apparent effect on protein processing. Interestingly, the K210E substitution, close to the VP1/2A junction, completely blocked processing by 3C(pro) at this cleavage site, but efficient assembly of "self-tagged" empty capsid particles, containing the uncleaved VP1-2A, was observed. These self-tagged particles behaved like the unmodified empty capsids in antigen enzyme-linked immunosorbent assays and integrin receptor binding assays. Furthermore, mutant viruses with uncleaved VP1-2A could be rescued in cells from full-length FMDV RNA transcripts encoding the K210E substitution in VP1. Thus, cleavage of the VP1/2A junction is not essential for virus viability. The production of such engineered self-tagged empty capsid particles may facilitate their purification for use as diagnostic reagents and vaccines.
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  • Article
    Wang D, Huang C, Bao S, Fan T, Sun Z, Wang Y, Jiang H, Wang S.
    Sci Rep. 2021 06 02;11(1):11591.
    Making timely assessments of disease progression in patients with COVID-19 could help offer the best personalized treatment. The purpose of this study was to explore an effective model to predict the outcome of patients with COVID-19. We retrospectively included 188 patients (124 in the training set and 64 in the test set) diagnosed with COVID-19. Patients were divided into aggravation and improvement groups according to the disease progression. Three kinds of models were established, including the radiomics, clinical, and combined model. Receiver operating characteristic curves, decision curves, and Delong's test were used to evaluate and compare the models. Our analysis showed that all the established prediction models had good predictive performance in predicting the progress and outcome of COVID-19.
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  • Article
    Hirata A, Kohara S, Asada T, Arao M, Yogi C, Imai H, Tan Y, Fujita T, Chen M.
    Nat Commun. 2016 05 13;7:11591.
    Solid silicon monoxide is an amorphous material which has been commercialized for many functional applications. However, the amorphous structure of silicon monoxide is a long-standing question because of the uncommon valence state of silicon in the oxide. It has been deduced that amorphous silicon monoxide undergoes an unusual disproportionation by forming silicon- and silicon-dioxide-like regions. Nevertheless, the direct experimental observation is still missing. Here we report the amorphous structure characterized by angstrom-beam electron diffraction, supplemented by synchrotron X-ray scattering and computer simulations. In addition to the theoretically predicted amorphous silicon and silicon-dioxide clusters, suboxide-type tetrahedral coordinates are detected by angstrom-beam electron diffraction at silicon/silicon-dioxide interfaces, which provides compelling experimental evidence on the atomic-scale disproportionation of amorphous silicon monoxide. Eventually we develop a heterostructure model of the disproportionated silicon monoxide which well explains the distinctive structure and properties of the amorphous material.
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  • Article
    Pérez-Estrada DE, Vargas-Villagrán H, Mendoza-Cruz R, Klimova TE.
    Nanoscale. 2024 Jun 20;16(24):11575-11591.
    Monometallic Ni, Pd and Pt and bimetallic catalysts formed by combinations of the above metals supported on SBA-15 silica were synthesized, characterized and tested in the hydrodeoxygenation reaction of anisole. The objective of the work was to detect the effect of the nature of metals on the activity of the catalysts at different steps of anisole hydrodeoxygenation: hydrogenation of the aromatic ring of anisole and C-O bond cleavage in the intermediate cyclohexyl methyl ether. The support and the catalysts were characterized by N2 physisorption, X-ray diffraction, UV-vis diffuse reflectance spectroscopy, temperature-programmed reduction, scanning electron microscopy-energy dispersive X-ray spectroscopy, transmission electron microscopy and HAADF-STEM. The catalytic activity tests were carried out in a batch reactor at 280 °C and 7.3 MPa pressure. The activity results show that the NiPd/SBA-15 catalyst had the greatest ability for hydrogenation of the aromatic ring of anisole, while its NiPt/SBA-15 analog resulted in better activity for C-O bond hydrogenolysis. The bimetallic NiPt/SBA-15 catalyst showed the best catalytic performance in the HDO of anisole ascribed to the formation of a Ni-Pt alloy. On the other hand, the combination of Pd and Pt metals in the PdPt/SBA-15 catalyst resulted in the formation of bimetallic particles with Pd-rich and Pt-rich domains, showing high selectivity for the formation of the cyclohexyl methyl ether, which can be useful for the hydrogenation of aromatic rings in O-containing reactants with the formation of saturated O-containing products. According to the characterization results (HAADF-STEM), the different catalytic behavior of NiPd/SBA-15, NiPt/SBA-15, and PdPt/SBA-15 catalysts could be attributed to different characteristics of the bimetallic active phases in them.
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  • Article
    Yen HC, Cabral H, Mi P, Toh K, Matsumoto Y, Liu X, Koori H, Kim A, Miyazaki K, Miura Y, Nishiyama N, Kataoka K.
    ACS Nano. 2014 Nov 25;8(11):11591-602.
    Nanomedicines capable of smart operation at the targeted site have the potential to achieve the utmost therapeutic benefits. Providing nanomedicines that respond to endogenous stimuli with an additional external trigger may improve the spatiotemporal control of their functions, while avoiding drawbacks from their inherent tissue distribution. Herein, by exploiting the permeabilization of endosomes induced by photosensitizer agents upon light irradiation, we complemented the intracellular action of polymeric micelles incorporating camptothecin (CPT), which can sharply release the loaded drug in response to the reductive conditions of the cytosol, as an effective strategy for precisely controlling the function of these nanomedicines in vivo, while advancing toward a light-activated chemotherapy. These camptothecin-loaded micelles (CPT/m) were stable in the bloodstream, with minimal drug release in extracellular conditions, leading to prolonged blood circulation and high accumulation in xenografts of rat urothelial carcinoma. With the induction of endosomal permeabilization with the clinically approved photosensitizer, Photofrin, the CPT/m escaped from the endocytic vesicles of cancer cells into the cytosol, as confirmed both in vitro and in vivo by real-time confocal laser microscopies, accelerating the drug release from the micelles only in the irradiated tissues. This spatiotemporal switch significantly enhanced the in vivo antitumor efficacy of CPT/m without eliciting any toxicity, even at a dose 10-fold higher than the maximum tolerated dose of free CPT. Our results indicate the potential of reduction-sensitive drug-loaded polymeric micelles for developing safe chemotherapies after activation by remote triggers, such as light, which are capable of permeabilizing endosomal compartments.
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  • Article
    Zaccheo BA, Crooks RM.
    Langmuir. 2011 Sep 20;27(18):11591-6.
    Here, we report that a conductive Au@Ag(2)O nanoparticle structure significantly enhances the stability of alkaline phosphatase (AlkP) in the presence of the inhibitors urea and l-phenylalanine (Phe). The enzyme/nanoparticle construct is prepared by associating the enzyme with citrate-capped Au particles, and then adding Ag(+). UV-vis and XPS spectroscopy and transmission electron microscopy confirm the core@shell structure. AlkP activity was quantified in the presence and absence of the two inhibitors using a time-resolved colorimetric assay. The results indicate that 21% of the initial active AlkP is incorporated into the nanoparticle structure. More importantly, however, the Au@Ag(2)O core@shell host reduces the inhibitory effect of urea and Phe by factors ranging from 3 to 12, depending on the inhibitor and its concentration, compared to the wild-type enzyme.
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  • Article
    Aresta G, Jacobs C, Araújo T, Cunha A, Ramos I, van Ginneken B, Campilho A.
    Sci Rep. 2019 08 12;9(1):11591.
    We propose iW-Net, a deep learning model that allows for both automatic and interactive segmentation of lung nodules in computed tomography images. iW-Net is composed of two blocks: the first one provides an automatic segmentation and the second one allows to correct it by analyzing 2 points introduced by the user in the nodule's boundary. For this purpose, a physics inspired weight map that takes the user input into account is proposed, which is used both as a feature map and in the system's loss function. Our approach is extensively evaluated on the public LIDC-IDRI dataset, where we achieve a state-of-the-art performance of 0.55 intersection over union vs the 0.59 inter-observer agreement. Also, we show that iW-Net allows to correct the segmentation of small nodules, essential for proper patient referral decision, as well as improve the segmentation of the challenging non-solid nodules and thus may be an important tool for increasing the early diagnosis of lung cancer.
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  • Article
    Wen X, Luo Y, Deng Y, Zeng X, Tian Y, He J, Hou X.
    Nanoscale. 2023 Jul 13;15(27):11582-11591.
    Real-time acquisition of the morphological information of nanomaterials is crucial to achieving morphological controllable synthesis, albeit being challenging. A novel device was designed, which integrated dielectric barrier discharge (DBD) plasma synthesis and simultaneous in situ spectral monitoring of the formation of metal-organic frameworks (MOFs). Important dynamic luminescence behaviors such as coordination induced emission (CIE), antenna effect (AE), and red-blue shift were continuously captured to reveal the spectral emission mechanism and energy transfer progress and verify the correlation with the morphological evolution of the MOFs. The prediction and control of morphology were successfully achieved with Eu(TCPP) as a model MOF. The proposed method will shed new light on exploring the spectral emission mechanism, energy conversion and in situ morphology monitoring of other luminescent materials.
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