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The vacuum impregnation resin method was used to prepare composite bipolar plates in fuel cell in this study. The effects of the content of epoxy resin diluent added, temperature and pore structure of graphite on the impregnation content during the vacuum impregnation process were studied. The electrical conductivity, flexural strength and airtightness of the prepared fuel cell bipolar plates were investigated. The results show that increasing the content of diluent and temperature can reduce viscosity and increase the upper limit of resin impregnation, enabling the resin to impregnate and fill into smaller pores, while there are still some pores that cannot be filled and saturated, such as the pores below 0.1 μm are difficult to fully penetrate in the expanded graphite plate, resulting in the resin being unable to completely fill the entire pores of the expanded graphite. The optimal temperature for impregnating the epoxy resin/diluent system by vacuum impregnation is 50 ℃, and the optimal addition ratio of diluent ethylene glycol diglycidyl ether is 15%(mass fraction). The obtained bipolar plate has excellent electrical conductivity of 340.12 S/cm, flexural strength of 41.52 MPa, and helium permeability of 5.4×10-7 cm3·cm-2·s-1.

In this paper, a titanium dioxide/covalent organic framework (TiO2/COF) composite was prepared and its photocatalytic removal of dye was investigated. Using tetrabutyl titanate as a titanium source, TiO2 nanomaterial was prepared by sol‐gel method. In the presence of TiO2, TiO2/COF core‐shell composite was prepared by solvothermal synthesis using melamine and 1,4‐phthalaldehyde as ligands. The prepared materials are characterized by SEM, TEM, XPS, XRD, TG, FTIR, BET, EPR, PL, and UV‐Vis‐DRS techniques. Using malachite green as a model of dye wastewater, the photocatalytic degradation performance of TiO2/COF composites was investigated under the irradiation of ultraviolet light. The results show that the modification of COF significantly improves the photocatalytic efficiency of TiO2, the degradation rate increases from 69.77 % to 93.64 %, and the reaction rate constant of the first‐order kinetic equation is increased from 0.0078 min−1 to 0.0192 min−1. Based on the free radical capture experiment, the photocatalytic degradation mechanism of TiO2/COF was discussed, and the feasibility of its photocatalytic degradation of malachite green was theoretically clarified. Accordingly, a simple and practical method for photocatalytic degradation of malachite green was constructed, which has potential application value in the degradation of dye wastewater. [ABSTRACT FROM AUTHOR]

Cervical cancer (CC) is a huge threat to the health of women worldwide. Long non-coding RNA plasmacytoma variant translocation 1 gene (PVT1) was proved to be associated with the development of diverse human cancers, including CC. Nevertheless, the exact mechanism of PVT1 in CC progression remains unclear. Levels of PVT1, microRNA-503 (miR-503), and ADP ribosylation factor-like protein 2 (ARL2) were measured by quantitative reverse transcription-polymerase chain reaction or western blot assay. 3-(4,5)-Dimethylthiazole-2-y1)-2,5-biphenyl tetrazolium bromide (MTT) and flow cytometry were used to examine cell viability and apoptosis, respectively. For migration and invasion detection, transwell assay was performed. The interaction between miR-503 and PVT1 or ARL2 was shown by dual luciferase reporter assay. A nude mouse model was constructed to clarify the role of PVT1 in vivo. PVT1 and ARL2 expressions were increased, whereas miR-503 expression was decreased in CC tissues and cells. PVT1 was a sponge of miR-503, and miR-503 targeted ARL2. PVT1 knockdown suppressed proliferation, migration, and invasion of CC cells, which could be largely reverted by miR-503 inhibitor. In addition, upregulated ARL2 could attenuate si-PVT1-mediated anti-proliferation and anti-metastasis effects on CC cells. Silenced PVT1 also inhibited CC tumor growth in vivo. PVT1 knockdown exerted tumor suppressor role in CC progression via the miR-503/ARL2 axis, at least in part.

Background: Endometrial dysfunction is closely correlated with the development of multiple severe gynecological disorders including intrauterine adhesion. Accumulating evidence supports that some long non‐coding RNAs (lncRNAs) have peptide‐coding potential. In this text, the peptide‐coding ability of lncRNA SNHG6 was examined. Also, the effects of an SNHG6‐encoded peptide on the viability and migration of human endometrial stromal cells (hESCs) and human endometrial epithelial cells (hEECs) and related molecular mechanisms were explored. Methods: The peptide‐encoding potential of SNHG6 was predicted by FuncPEP and getorf databases and validated by western blot assay. Cell viability was tested by cell counting kit‐8 assay. Cell migratory ability was examined by wound healing and transwell migration assays. Protein levels of genes were measured by western blot assay. Results: Prediction analysis suggested that SNHG6 had the potential peptide‐coding ability and multiple open‐reading frames (ORFs). Western blot validated that SNHG6 ORF#1 and ORF#2 could translate into short peptides. SNHG6 ORF#2 overexpression facilitated cell migration and epithelial–mesenchymal transition (EMT) in hESCs and hEECs, while these effects were abrogated by transforming growth factor‐beta (TGF‐β)/SMAD signaling inhibitor GW788388. Moreover, GW788388 inhibited the increase of p‐SMAD2 and p‐SMAD3 levels induced by SNHG6 ORF#2 in hESCs. SNHG6 ORF#2‐encoded peptide did not influence endometrial stromal and epithelial cell viability. Conclusions: LncRNA SNHG6 ORF#1 and ORF#2 could translate into small peptides and SNHG6 ORF#2 overexpression promoted cell migration and EMT by activating the TGF‐β/SMAD pathway in hESCs and hEECs, suggesting the potential roles of SNHG6‐encoded peptides in the development of endometrial stromal and epithelial cells and related gynecological diseases. [ABSTRACT FROM AUTHOR]

In this paper, covalent organic frameworks (COFs) are prepared by solvothermal synthesis using 1,3,5-benzenetricarboxaldehyde and benzidine as ligands. Then, using COFs as a template, AgCOFs with high catalytic activity is prepared by in situ loading silver nanoparticles (AgNC) on the surface of COFs by sodium borohydride reduction method. AgCOFs are characterized by TEM, SEM, FTIR and XRD. At the same time, the catalytic ability of AgCOFs for trisodium citrate-AgNO3 nanosilver reaction is studied. The results show that AgCOFs can catalyze the reaction of trisodium citrate-AgNO3 to generate silver nanoparticles (AgNPs). The solution color of the system gradually changes from colorless to yellow, and the absorbance value increases. Based on the catalytic reaction of AgCOFs and the regulation effect of nucleic acid aptamer reaction on AgCOFs, a new "on–off–on" colorimetric analysis platform is constructed and applied to the detection of trace Pb2+ in water samples. This analytical platform is simple, sensitive and selective. Finally, the catalytic mechanism of the system is discussed to verify the feasibility of constructing a colorimetric analysis platform. [ABSTRACT FROM AUTHOR]