Energy effective utilization of circulating fluidized bed fly ash to prepare silicon-aluminum composite aerogel and gypsum.

To reduce the cost of Si-Al aerogels preparation, circulating fluidized bed fly ash (CFA) was developed to be as the alternative to synthetic precursors. High energy consumption of alkali-melting and secondary wastes production were the major challenges. Here, a technique characterized by effective energy consumption and non-secondary waste was developed to convert CFA into Si-Al aerogel. The process consists two stages, preparation of Si-Al sol by sintering of CFA and Na2CO3 followed by sulfuric acid leaching, and synthesis of Si-Al aerogel by so-gel with trimethyl chlorosilane modification and ambient pressure drying. The optimization results of proportion and sintering temperature showed that the optimal temperature of sintering of Na2CO3 and CFA with the mass ratio of 0.7 was 750 °C, 100 °C lower than that of most other waste aluminosilicate materials. CaSO4·0.5H2O which meet building gypsum requirement was obtained by specifying the drying temperature of acid-leached residue at 126 °C for 2 h. The modification procedure was explored to obtain Si-Al aerogel with a large specific surface area of 857 m2/g and hydrophobic angle of 139.3°. Thermal and mechanical properties tests indicated that the Si-Al aerogels and gypsum produced from CFA exhibited promising thermal insulation and the potential application in construction.

Revealing the Electrocatalytic Self-Assembly Route from Building Blocks into Giant Mo-Blue Clusters.

The assembly of single-core molybdate into hundreds of cores of giant molybdenum blue (Mo-blue) clusters has remained a long-standing unresolved scientific puzzle. To reveal this fascinating self-assembly behavior, we demonstrate an aqueous flowing in-operando Raman characterization system to capture the building blocks' evolution from the "black box" reaction process. We successfully visualized the sequential transformation of Na2MoO4 into Mo7O246- ({Mo7}), high nuclear Mo36O1128- ({Mo36}) cluster, and finally polymerization product of [H6K2Mo3O12(SO4)]n ({Mo3(SO4)}n) during the H2SO4 acidification. Notably, the facile conversion of {Mo3(SO4)}n back to the {Mo36} cluster by simple dilution is also discovered. Furthermore, we identified {Mo36} and {Mo3(SO4)}n as exclusive precursors responsible for driving the electrochemical self-assembly of {Mo154} and {Mo102}, respectively. The study also unravels a pivotal intermediate, the pentagonal reduced state fragment [H18MoVI4MoVO24]-, originating from {Mo36}, which catalyzes the autocatalytic self-assembly of {Mo154} with electron and proton injection during electrochemical processes. Concurrently, {Mo3(SO4)}n serves as the indispensable precursor for {Mo102} formation, generating sulfation pentagon building blocks of [H2Na2O2(H4MoVMoVI4O16SO4)4]4- that facilitate the consecutive assembly of giant {Mo102} sphere clusters. As a result, a complete elucidation of the assembly pathway of giant Mo-blue clusters derived from single-core molybdate was obtained, and H+/e- redox couple is revealed to play a critical role in catalyzing the deassembly of the precursor, leading to the formation of thermodynamically stable intermediates essential for further self-assembly of reduced state giant clusters.

Insights into the self-assembly of giant polyoxomolybdates from building blocks to supramolecular structures.

Giant polyoxomolybdates are a special class of polyoxometalate clusters which can bridge the gap between small molecule clusters and large polymeric entities. Besides, giant polyoxomolybdates also show interesting applications in catalysis, biochemistry, photovoltaic and electronic devices, and other fields. Revealing the evolution route of the reducing species into the final cluster structure and also their further hierarchical self-assembly behaviour is undoubtedly fascinating, aiming to guide the design and synthesis. Herein, we reviewed the self-assembly mechanism study of giant polyoxomolybdate clusters, and the exploration of a new structure and new synthesis methodology is also summarized. Finally, we emphasize the importance of in-operando characterization in revealing the self-assembly mechanism of giant polyoxomolybdates, and especially for the further reconstruction of intermediates into the designable synthesis of new structures.

Combination therapy of hydrogel and stem cells for diabetic wound healing.

Diabetic wounds (DWs) are a common complication of diabetes mellitus; DWs have a low cure rate and likely recurrence, thus affecting the quality of patients' lives. As traditional therapy cannot effectively improve DW closure, DW has become a severe clinical medical problem worldwide. Unlike routine wound healing, DW is difficult to heal because of its chronically arrested inflammatory phase. Although mesenchymal stem cells and their secreted cytokines can alleviate oxidative stress and stimulate angiogenesis in wounds, thereby promoting wound healing, the biological activity of mesenchymal stem cells is compromised by direct injection, which hinders their therapeutic effect. Hydro-gels form a three-dimensional network that mimics the extracellular matrix, which can provide shelter for stem cells in the inflammatory microenvironment with reactive oxygen species in DW, and maintains the survival and viability of stem cells. This review summarizes the mechanisms and applications of stem cells and hydrogels in treating DW; additionally, it focuses on the different applications of therapy combining hydrogel and stem cells for DW treatment.

Construction and Application of Standardized Postoperative Pain-Management Procedure for Patients With Perianal Abscess: A Retrospective Study.

Objective: The present study explored the construction and application of a standardized postoperative pain-management procedure for patients with perianal abscess. Methods: Two study groups (the observation group and the intervention group) were established retrospectively. The observation group comprised 46 patients with perianal abscess who enrolled in this study between June 2019 and June 2020. The intervention group comprised 48 patients who enrolled in the study between July 2020 and July 2021. All patients were enrolled using the convenience sampling method. A pain-management team was established, and standardized procedure management was implemented in the intervention group, while routine pain management was implemented in the observation group. Indices related to the patients' postoperative pain-control satisfaction and rehabilitation were compared between the two groups. Results: The patients' pain-control satisfaction, wound edema score, edema disappearance time, urinary retention, and defecation difficulty following intervention were better in the intervention group than in the observation group, and the differences were statistically significant (P < 0.05 for all). Conclusion: The implementation of the standardized postoperative pain-management procedure in patients with perianal abscess can effectively improve the patient's level of pain and satisfaction and promote rehabilitation.

Porous {P6Mo18O73}-type Poly(oxometalate) Metal-Organic Frameworks for Improved Pseudocapacitance and Electrochemical Sensing Performance.

{P6Mo18} poly(oxometalate) (POM) clusters have huge steric hindrance and limited active oxygen atoms, which make them difficult to combine with metal-organic units to form three-dimensional (3D) porous structures. Therefore, functionalization of such POMs has always been a bottleneck that is difficult to break through. In this study, {P6Mo18} POM was successfully grafted on a lock-like metal-organic chain to generate a multiporous coordination polymer, [{Na(H2O)(H2btb)}{Cu4I(H2O)(pz)5Cl}{H2Sr⊂P6Mo2VMo16VIO73}]·3H2O (1) (pz = pyrazine; btb = 1,4-bis(1,2,4-triazole) butane). Meanwhile, a zero-dimensional (0-D) control compound with only btb ligands as counterions, (H4btb)[H4Sr⊂P6Mo2VMo16VIO73]·3H2O (2), was also obtained via a hydrothermal reaction. Compound 1 represents the first basket-type 3D poly(oxometalate) metal-organic framework (POMOF) assembly, which possesses interpenetrating pores and complex topology. 1-GO-CPE displays improved supercapacitor (SC) performance (the specific capacitance of 929.4 F g-1 at a current density of 3 A g-1 with 94.1% of cycle efficiency after 5000 cycles) compared with 2-GO-CPE and most reported POMOF electrode materials, which may be due to the outstanding redox capability of basket-POM, introduction of metal-organic chains, intersecting pores, and excellent conductivity of graphene. An asymmetric SC device with 1-GO-CPE as the negative electrode exhibits an energy density of 29.7 Wh kg-1 with a power density of 3148.2 W kg-1 and long-lasting cycling life. In addition, 1-GO-GCE as an electrochemical sensor responds to dopamine (DA) at a voltage of 0.40 V and shows lower detection limits (0.19 µM (signal-to-noise ratio (SNR) = 3)), higher selectivity, and good reproducibility in the linear range of 0.56 µM to 0.24 mM. The ability to accurately detect the content of DA in biological samples further proves the feasibility of the sensor in practical applications.

A DFT study of the catalytic pyrolysis of benzaldehyde on ZnO, γ-Al2O3, and CaO models.

The catalytic pyrolysis pathways of carbonyl compounds in coal were systematically studied using density functional theory (DFT), with benzaldehyde (C6H5CHO) employed as a coal-based model compound and ZnO, γ-Al2O3, and CaO as catalysts. The results show that the products of both pyrolysis and catalytic pyrolysis are C6H6 and CO. However, the presence of any of the catalysts changes the reaction pathway and reduces the energy barrier, indicating that these catalysts promote C6H5CHO decomposition. Graphical abstract The presence of catalysts changes the reaction pathway and the energy barrier decreases in the order Ea (no catalyst)> Ea (CaO)> Ea (γ-Al2O3)> Ea (ZnO), indicating that these catalysts promote C6H5CHO decomposition.

MicroRNA-146a modulates TGF-ß1-induced phenotypic differentiation in human dermal fibroblasts by targeting SMAD4.

During wound healing and tissue repair the dermal fibroblast-to-myofibroblast transdifferentiation plays an important role, transforming growth factor-ß1 (TGF-ß1) is considered to be the main stimuli factor of transdifferentiation. MicroRNAs (miRNAs) have recently emerged as key post-transcriptional regulators of gene expression. The involvement of miRNAs and their roles in TGF-ß1-induced myofibroblast transdifferentiation remains to be determined in detail. The current study found that the expression of miR-146a was upregulated in human dermal fibroblasts cells in response to TGF-ß1 stimulation in dose-dependent manner by quantitative RT-PCR. Bioinformatic analyses predict that signaling effectors mothers against decapentaplegic protein 4 (SMAD4) is a miR-146a target gene. Luciferase assay demonstrated that miR-146a mimics suppressed SMAD4 3'-UTR reporter construct activity. Furthermore, miR-146a overexpression in dermal fibroblast did not decrease target mRNA levels, but significantly reduced target protein expression. In addition, dermal fibroblasts transfected with miR-146a mimics exhibited attenuated TGF-ß1 -induced α-smooth muscle actin (α-SMA) expression compared with the control. This study demonstrated that miR-146a may function as a novel negative regulator to modulate myofibroblast transdifferentiation during TGF-ß1 induction by targeting SMAD4.