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In this work, a metal organic framework (Fe‐MOF) with the effect of absorbing toxic gases and good compatibility was synthesized by chelating a novel organic ligand contained carbonization groups (reacted by tris(hydroxymethyl) aminomethane and 1,4‐piperazine dialdehyde) with iron salt. Then, it was used as the synergist to improve the efficiency of intumescent flame retardant (IFR) within polystyrene (PS) substrate. With the addition of 20% IFR and 2% Fe‐MOF, the obtained PS composites exhibited a limiting oxygen index (LOI) value of 28.3% and a UL rating of V‐0. Moreover, the peak heat release rate (pHRR), total heat release (THR), and total smoke production (TSP) of PS composites were decreased by 77.6%, 35.2%, and 33.7%, respectively. According to the mechanism analysis, it was found that Fe‐MOF mainly acted in the condensed phase, contributing to the existence of dense char residues with the presence of IFR system. In addition, the good compatibility of organic ligand in Fe‐MOF with PS substrate could partially alleviate the deterioration of mechanical properties due to the addition of IFR. For PS‐20%IFR/2%Fe‐MOF, the impact strength was improved from 1.7 kJ/m2 (PS‐22%IFR) to 2.2 kJ/m2, the tensile strength was also increased from 21.3 MPa (PS‐22%IFR) to 22.4 MPa. [ABSTRACT FROM AUTHOR]

It is possible to remove volatile organic compounds containing chlorine (CVOCs, such as chlorobenzene) in a single device designed for selective catalytic reduction of NOX with NH3 for the industries containing CVOCs and NOX. Breaking the efficiency-selectivity trade-off in chlorobenzene oxidation remains a major challenge due to the conjugation of halogen atoms with the benzene ring and the reducing nature of NH3. A stepwise synthesis strategy is demontrated to disperse dual Ru/Cu Lewis acid sites outside and inside the zeolite channel. Under the confinement of zeolite, the Ru4+ Lewis acid site on the external surface of the zeolite promotes chlorobenzene oxidation by weakening the p-n conjugate structure of Cl and benzene ring, while the Cu2+ Lewis acid site within the internal channel converts NOX and NH3 to N2. The mutual interference between catalytic oxidation and reduction is successfully avoided. Therefore, the low toxic CO2 and HCl selectivity experience a considerable increase from 21% to 86%, and from 51% to 94% with 91% conversion of chlorobenzene, while maintaining excellent elimination performance for NO (with N2 selectivity exceeding 90%). The incorporation of separated active sites and reaction spaces into the design may offer potentials for other energy and environmental applications. [ABSTRACT FROM AUTHOR]

Background: Triple‐negative breast cancer (TNBC) is a common hypotype of breast cancer. Circular RNAs (circRNAs) are burgeoning serve as vital controllers in numerous tumors. Nevertheless, the expression and regulatory mode of circRNAs in TNBC are still indistinct. This paper aimed to reveal the function and molecular mechanism of circular RNA dehydrodolichyl diphosphate synthase (circDHDDS) in TNBC. Methods: The contents of circDHDDS, DHDDS mRNA, microRNA‐362‐3p (miR‐362‐3p) and DEAD (Asp‐Glu‐Ala‐Asp) box polypeptide 5 (DDX5) were indicated by quantitative real‐time polymerase chain reaction (qRT‐PCR) and western blot. The colony formation assay and 5‐ethynyl‐2'‐deoxyuridine (EdU) assay were executed to assess cell proliferation. The flow cytometry assay was utilized to detect cell apoptosis. The transwell assay and tube formation assay were applied to measure cell migration, invasion and angiogenesis. The targeted relationships of miR‐362‐3p and circDHDDS or DDX5 were forecasted and detected by dual‐luciferase reporter assay. The in vivo test was implemented to confirm the effect of circDHDDS. Results: The contents of circDHDDS and DDX5 were increased, and miR‐362‐3p level was decreased in TNBC. CircDHDDS deficiency reserved cell proliferation, migration, invasion and angiogenesis, while facilitated cell apoptosis in TNBC cells. Furthermore, miR‐362‐3p was validated to exert a tumor repressive effect in TNBC cells by suppressing DDX5. Moreover, DDX5 could regulate the development of TNBC. The experimental data exposed that levels of miR‐362‐3p presented noteworthy negative correlation with circDHDDS and DDX5, while circDHDDS and DDX5 exhibited significant positive correlation. In mechanism, circDHDDS bound to miR‐362‐3p to modulate DDX5 expression. In addition, circDHDDS knock‐down also attenuated tumor growth. Conclusion: CircDHDDS expedited TNBC by swelling DDX5 via adapting miR‐362‐3p. [ABSTRACT FROM AUTHOR]

The wildly‐used charring agent, pentaerythritol (PER), was solely incorporated into polyamide 11 (PA 11) matrix by melt compounding. The addition of 15%PER improved the UL rating of PA 11‐PER composites to V‐0 and reduced the peak heat release rate by 22.1%. Most importantly, the time to ignition had been incredibly increased from 93 s of neat PA 11 to 193 s of PA 11‐15PER sample. The thermal behaviors were investigated by thermogravimetric analysis (TGA) and TGA‐Fourier transform infrared (FTIR). The morphology, chemical structure and physical properties (such as crystallinity and viscosity) of char residues that were collected at ignition point or after MLC tests of PA 11 and PA 11‐15PER composites were fully demonstrated. It was suggested that the interactions between PA 11 and PER led to the rapid formation of a compact char layer which exhibited sufficient viscosity before ignition in the condensed phase, while the early released H2O and CO2 from PER took effects in the gas phase. [ABSTRACT FROM AUTHOR]

In this work, a novel sulfur‐based flame retardant (SA‐M) was synthesized by the self‐assembly of melamine and sulfamic acid. The chemical structure of SA‐M was fully characterized. SA‐M, in company with Al2O3, was then introduced into polyamide 11 (PA 11) by melt compounding in order to improve the fire resistance of the polymer substrate. The observation by scanning electron microscopy (SEM) and electron probe microanalysis (EPMA) indicated the well dispersion of SA‐M in PA 11 matrix. The fire performance of PA 11 composites was evaluated by limiting oxygen index (LOI), vertical burning (UL‐94), and cone calorimeter tests, respectively. The results showed that the presence of 17.5% SA‐M and 2.5% Al2O3 increased the LOI value from 22.4% to 30.9%, upgraded the UL‐94 rating from no rating to V‐0, significantly eliminated the melt dripping, and decreased the peak heat release rate from 1024 to 603 kW/m2. The thermal behaviors were investigated by thermogravimeric analysis (TGA) and TGA‐Fourier transform infrared spectroscopy (FTIR). It was suggested that SA‐M took effects mainly in gas phase by diluting the combustible fuel, leading to the improvement of the fire resistance of PA 11. [ABSTRACT FROM AUTHOR]

The commercial fluorocarbon surfactant (FCS) DuPont™ Zonyl 321 fluorinated cationic surfactants, was employed to modify both flat‐sheet and hollow‐fiber poly(tetrafluoroethylene) (PTFE) porous membranes. The variation of morphology, wettability, and hydrophilicity durability to acid and alkali as well as the filtration performance of both membranes were investigated. Such superhydrophilic membranes showed better wetting stability and higher resistance to acid and alkali solutions. Moreover, both membranes exhibited good filtration performance. [ABSTRACT FROM AUTHOR]

Sodium lignosulfonate (SL), a byproduct of the pulping industry, was used as a stabilizer for the mineralization of CaCO3. In a calcium acetate-urea-water system, the direct aging of the aqueous solution of calcium acetate and urea resulted in the formation of mixed aragonite and vaterite phases or a pure aragonite phase depending on the aging time. However, SL was introduced into the calcium acetate-urea-water system to markedly stabilize the formation of a thermodynamically unstable vaterite phase. Various morphologies of vaterite structures were observed by adjusting the concentration of urea and SL as well as the aging time. Based on these results, ion exchange, carbonate attacking the calcium(II) ions, aggregations of SL-stabilized primary CaCO3 particles through oriented attachment and Ostwald ripening, as well as mesoscale self-assembly were proposed as mechanisms to elucidate the formation of various morphologies. [ABSTRACT FROM AUTHOR]

This study is based on the three types of residential buildings with framework structures in Beijing: concrete framework construction (CFC), light-gauge steel framework construction (SFC), and wood framework construction (WFC). The analysis of the environmental load across the life cycle of the three types of buildings is conducted using life cycle assessment (LCA) according to the protocols of the International Organization for Standardization (ISO) 14040/44. The functional unit is the three material building designs, which possess the same function and design plan, and are built in concrete, light-gauge steel, and light frame wood, inclusive of their respective envelope materials. Throughout the investigation, the calculations of the environmental load data of materials, energy consumption, and carbon dioxide (CO2) emissions are comprehensively assessed and compared. The study shows that over the life cycle, the energy consumption of CFC is almost the same as that of SFC, and each of them is approximately 30% higher than that of WFC. Building use, steel material production, cement production, gypsum board production, and material transport are the main construction activities related to the energy consumption; the net CO2 emission of CFC is 44% higher than that of SFC and 49% higher than that of WFC. The main source of CO2 emission is the use of electricity; its contributions to the net CO2 emissions of WFC, SFC, and CFC are 67%, 64%, and 44%, respectively. The net CO2 emissions in the transport category cannot be ignored, with proportions amounting to 8%, 12%, and 11% for WFC, SFC, and CFC, respectively. [ABSTRACT FROM AUTHOR]