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Polyvinylidene fluoride (PVDF) has unique electrochemical oxidation resistance and is the only binder for high-voltage cathode materials in the battery industry for a long time. However, PVDF still has some drawbacks, such as environmental limitations on fluorine, strict requirements for environmental humidity, weak adhesion, and poor lithium ion conductivity. Herein, the long-standing issues associated with high-voltage lithium cobalt oxide (LiCoO2; LCO) are successfully addressed by incorporating phenolphthalein polyetherketone (PEK-C) and phenolphthalein polyethersulfone (PES-C) as binder materials. These binders have unexpected electrochemical oxidation resistance and robustness adhesion, ensure uniform coverage on the surface of LCO, and establish an effective and fast ion-conductive CEI/binder composite layer. By leveraging these favorable characteristics, electrodes based on polyarylether binders demonstrate significantly better cycling and rate performance than their counterparts using traditional PVDF binders. The fast ion-conductive CEI/binder composite layer effectively mitigates adverse reactions at the cathode-electrolyte interface. As anticipated, batteries utilizing phenolphthalein polyarylether binders exhibit capacity retention rates of 88.92% and 80.4% after 200 and 500 cycles at 4.5 and 4.6 V, respectively. The application of binders, such as polyarylether binders, offers a straightforward and inspiring approach for designing high-energy-density battery materials.

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This paper describes a novel method for detecting and visualizing vortex structures in unsteady 2D fluid flows. The method is based on an interactive local reference frame estimation that minimizes the observed time derivative of the input flow field v(x, t). A locally optimal reference frame w(x, t) assists the user in the identification of physically observable vortex structures in Observed Line Integral Convolution (LIC) visualizations. The observed LIC visualizations are interactively computed and displayed in a user-steered vortex lens region, embedded in the context of a conventional LIC visualization outside the lens. The locally optimal reference frame is then used to detect observed critical points, where v=w, which are used to seed vortex core lines. Each vortex core line is computed as a solution of the ordinary differential equation (ODE) · w(t)=w(w(t), t), with an observed critical point as initial condition (w(t0), t0). During integration, we enforce a strict error bound on the difference between the extracted core line and the integration of a path line of the input vector field, i.e., a solution to the ODE · v(t)=v(v(t), t). We experimentally verify that this error depends on the step size of the core line integration. This ensures that our method extracts Lagrangian vortex core lines that are the simultaneous solution of both ODEs with a numerical error that is controllable by the integration step size. We show the usability of our method in the context of an interactive system using a lens metaphor, and evaluate the results in comparison to state-of-the-art vortex core line extraction methods.

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State-of-the-art computation and visualization of vortices in unsteady fluid flow employ objective vortex criteria, which makes them independent of reference frames or observers. However, objectivity by itself, although crucial, is not sufficient to guarantee that one can identify physically-realizable observers that would perceive or detect the same vortices. Moreover, a significant challenge is that a single reference frame is often not sufficient to accurately observe multiple vortices that follow different motions. This paper presents a novel framework for the exploration and use of an interactively-chosen set of observers, of the resulting relative velocity fields, and of objective vortex structures. We show that our approach facilitates the objective detection and visualization of vortices relative to well-adapted reference frame motions, while at the same time guaranteeing that these observers are in fact physically realizable. In order to represent and manipulate observers efficiently, we make use of the low-dimensional vector space structure of the Lie algebra of physically-realizable observer motions. We illustrate that our framework facilitates the efficient choice and guided exploration of objective vortices in unsteady 2D flow, on planar as well as on spherical domains, using well-adapted reference frames.

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Mesoporous bioactive glass (MBG) is a good scaffold for bone regeneration. In this study, amino functionalized MBG (N-MBG) was used as a model scaffold to examine the effect of the scaffold to bone marrow stromal cells (BMSCs) and macrophages. The MTT results revealed that the proliferation of BMSCs from ovariectomized rabbits was enhanced by N-MBG. Compared to the control group, the expression of osteogenic genes was significantly enhanced by N-MBG, which was related to CaSR pathway. Meanwhile, the anti-inflammatory cytokines (interleukin-10 and arginase-1) were also upregulated by N-MBG stimulation compared with MBG. Furthermore, the amino functionalization of MBG resulted in an increase in the pH value of the material extract. Interestingly, the formation of TRAP+ multinuclear cells was inhibited by the slightly alkaline extract to a certain extent, which reasonably explained the increase in TRAP+ multinuclear cells after adjusting the pH value of N-MBG extract. In vivo, the areas of new bone formation in the maxillary sinus floor elevation were increased in the N-MBG/BMSCs group with less TRAP+ multinuclear cells compared with the MBG/BMSCs group. These findings provided valuable insight that the osteogenic ability of MBG scaffold could be enhanced by amino functionalization due to coordinate BMSCs and macrophages differentiation.

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Our previous study revealed that mesoporous Ca-Si-based materials exhibited excellent osteoconduction because dissolved ions could form a layer of hydroxycarbonate apatite on the surface of the materials. However, the biological mechanisms underlying bone regeneration were largely unknown. The main aim of this study was to evaluate the osteogenic ability of large-pore mesoporous Ca-Si-based bioceramics (LPMSCs) by alkaline phosphatase assay, real-time PCR analysis, von Kossa, and alizarin red assay. Compared with large-pore mesoporous silica (LPMS), LPMSCs had a better effect on the osteogenic differentiation of dental pulp cells. LPMSC-2 and LPMSC-3 with higher calcium possessed better osteogenic abilities than LPMSC-1, which may be related to the calcium-sensing receptor pathway. Furthermore, the loading capacity for recombinant human platelet-derived growth factor-BB was satisfactory in LPMSCs. In vivo, the areas of new bone formation in the calvarial defect repair were increased in the LPMSC-2 and LPMSC-3 groups compared with the LPMSC-1 and LPMS groups. We concluded that LPMSC-2 and LPMSC-3 possessed both excellent osteogenic abilities and satisfactory loading capacities, which may be attributed to their moderate Ca/Si molar ratio. Therefore, LPMSCs with moderate Ca/Si molar ratio might be potential alterative grafts for craniomaxillofacial bone regeneration.

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A novel type of adsorbent for the selective recognition and adsorption of trace Pb2+ from aqueous solutions has been successfully constructed simply by grafting molecularly imprinted polymers (MIPs) onto hollow mesoporous silica (HMS). Attractively, the HMS loaded with MIPs (H-MIPs) exhibits a fast adsorption kinetics, marked adsorption capacity of 40.52mg/g and extremely high selectivity toward Pb2+ over Cu2+, Zn2+, Co2+, Mn2+ and Ni2+, and the selectivity coefficients have been determined to be as high as 50. Moreover, such high adsorptive capability and selectivity were retained for at least 6 runs, indicating the stability and reusability of H-MIPs. Lead ion contaminants in real water samples were successfully concentrated and approximately 100% recovered using H-MIPs. Theoretical analysis shows that the adsorption process of H-MIPs follows the pseudo-second-order kinetic and Langmuir isotherm models. These demonstrate that H-MIPs are greatly potential for the rapid and highly efficient removal of trace Pb2+ ions in complicated matrices.

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Natural antibodies are used widely for various applications such as in biomedical analysis, protein separation, and targeted-drug delivery, but they suffer from high cost and low stability. In this study, we developed a facile approach for the construction of antibody-like binding sites in a porous silica solid for efficient separation of bovine serum albumin (BSA) based on large-pore silica particles (LPSPs). This was accomplished by grafting two types of organosilane monomers, 3-aminopropyltriethoxylsilane (APTES) and octyltrimethoxysilane (OTMS), to provide hydrogen bonds or hydrophobic interactions with BSA through molecular imprinting technology. The resulting molecularly imprinted, large-pore silica particles (MI-LPSPs) were characterized by scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TG), X-ray diffraction (XRD) and N2 sorption analysis. Results showed that the as-synthesized MI-LPSPs exhibited a spherical morphology, favorable stability and large pore structure. The kinetic adsorption experiments showed that the MI-LPSPs could reach equilibrium within one hour and were described well by the pseudo second-order model, indicating that chemical adsorption might be the rate-limiting step. Meanwhile, the MI-LPSPs had a large binding capacity up to 162.82 mg g-1 and high selectivity for the recognition of BSA. Moreover, such a high binding capacity and selectivity was retained after six runs, indicating a good stability and reusability of MI-LPSPs. Thus, it is expected that a simple synthetic methodology in the present study provides a promising pathway to prepare novel imprinted materials for efficient purification and separation of target proteins.

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Mesoporous bioactive glass (MBG), which possesses excellent bioactivity, biocompatibility and osteoconductivity, has played an important role in bone tissue regeneration. However, it is difficult to prepare MBG scaffolds with high compressive strength for applications in bone regeneration; this difficulty has greatly hindered its development and use. To solve this problem, a simple powder processing technique has been successfully developed to fabricate a novel type of MBG scaffold (MBGS). Furthermore, amino or carboxylic groups could be successfully grafted onto MBGSs (denoted as N-MBGS and C-MBGS, respectively) through a post-grafting process. It was revealed that both MBGS and the functionalized MBGSs could significantly promote the proliferation and osteogenic differentiation of bMSCs. Due to its positively charged surface, N-MBGS presented the highest in vitro osteogenic capability of the three samples. Moreover, in vivo testing results demonstrated that N-MBGS could promote higher levels of bone regeneration compared with MBGS and C-MBGS. In addition to its surface characteristics, it is believed that the decreased degradation rate of N-MBGS plays a vital role in promoting bone regeneration. These findings indicate that MBGSs are promising materials with potential practical applications in bone regeneration, which can be successfully fabricated by combining a powder processing technique and post-grafting process.

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Mesoporous Ca-Si-based bioceramics represented by mesoporous bioactive glasses (MBG) have attracted much attention in the field of bone tissue regeneration due to their excellent bioactivity, biocompatibility and osteoconductivity. However, the small mesopores (<7 nm) have greatly hindered their ability to encapsulate macromolecular proteins with ability to significantly induce bone growth. To solve this problem, a novel type of large-pore mesoporous silica (LPMS) was first synthesized using a simple one-step method at high temperatures. Solid reactions were then carried out to synthesize large-pore mesoporous Ca-Si-based bioceramics (LPMSCs) using LPMS as both the template and silicon source, and Ca(NO3)2 as the calcium source. The prepared LPMSCs not only displayed large-diameter (>15 nm) mesopores, but also high in vitro bioactivities. Bovine serum albumin (BSA) was used as a model protein to evaluate the adsorption capacity and release properties of our synthesized products for proteins. The results demonstrated that BSA could be encapsulated into the LPMSCs, with a slow and sustained release behaviour. Furthermore, in vitro cell tests showed the LPMSCs to have a favourable effect on proliferation and osteogenetic differentiation. These findings indicate that LPMSCs could be used as a bioactive protein adsorption and release system for preparation of bone implant materials.

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In this work, a novel composite scaffold was constructed by combining mesoporous bioactive glass (MBG) and calcium phosphate cement (CPC) materials using a simple centrifugal embedding approach. Furthermore, recombinant human bone morphogenetic protein-2 (rhBMP-2) was facilely incorporated into this scaffold through a freeze-drying process. It is found that the resultant scaffold not only presents a hierarchical pore structure (interconnected pores of around 200 µm and 2-10 µm) and a sufficient compressive strength (up to 1.4 MPa), but also exhibits excellent drug delivery properties, presenting sustained release of rhBMP-2 for over 7 d. In order to evaluate the osteogenetic capacity of the rhBMP-2 loaded MBG/CPC scaffold, in vitro cell culture with bone marrow stromal cells (BMSCs) was conducted. Notably, this composite scaffold presents a favorable effect on the proliferation and osteogenetic differentiation of BMSCs. Furthermore, in vivo bone tissue regeneration was conducted using a rabbit radius defect model. It is demonstrated that the incorporation of rhBMP-2 can induce a significant improvement of osteogenetic efficiency, especially in the early stage. Moreover, better biodegradability was obtained in the rhBMP-2 loaded MBG/CPC scaffold compared to the others. Therefore, it is anticipated that the rhBMP-2 loaded MBG/CPC scaffold is of great potential in the field of rapid bone tissue regeneration.

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Uniform mesoporous zeolite ZSM-5 crystals have been successfully fabricated through a simple hydrothermal synthetic method by utilizing ammonium-modified chitosan and tetrapropylammonium hydroxide (TPAOH) as the meso- and microscale template, respectively. It was revealed that mesopores with diameters of 5-20 nm coexisted with microporous network within mesoporous ZSM-5 crystals. Ammonium-modified chitosan was demonstrated to serve as a mesoporogen, self-assembling with the zeolite precursor through strong static interactions. As expected, the prepared mesoporous ZSM-5 exhibited greatly enhanced catalytic activities compared with conventional ZSM-5 and Al-MCM-41 in reactions involving bulky molecules, such as the Claisen-Schmidt condensation of 2-hydroxyacetophenone with benzaldehyde and the esterification reaction of dodecanoic acid and 2-ethylhexanol.