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Biomethane power generation, particularly chemical looping combustion technology, has garnered significant attention recently due to its ability to capture CO 2 in situ. In this study, dual bed layers oxygen carriers (DBL) for chemical looping combustion of methane were designed. The LaFe 0.93 Ni 0.07 O 3 oxygen carrier with excellent CH 4 partial oxidation was applied in upper bed layer and low-cost red mud was located into lower bed layer. This tandem reaction showed much higher methane conversion (87.1 %) than that over the single oxygen carrier of red mud (33.9 %) and the mechanically mixed oxygen carrier of LaFe 0.93 Ni 0.07 O 3 and red mud (77.7 %). In addition, the mechanically mixed sample showed a quick deactivation, with the methane conversion dropping 54.2 % after 40 redox cycles due to the encapsulation of the active LaFe 0.93 Ni 0.07 O 3 by red mud, while the double bed system showed high stability in the long-term redox cycle. The limitedly increased crystallite size of LaFeO 3 , as well as completely replenished lattice oxygen, were responsible for superior activity and stability of DBL. This study provides a new strategy to improve the efficiency of chemical looping combustion of methane in fixed bed reactor by tandem reactions over different oxygen carriers with complementary functions in terms of activity and cost. • A tandem reactions strategy for improving the efficiency of chemical looping combustion of methane in fixed bed reactor was provided. • The obvious increased crystal size and coarsening particles can be alleviated by the double bed layer design. • The double bed layer design provides supports for direct utilization of red mud. [ABSTRACT FROM AUTHOR]

Heparin (Hep) or bivalirudin (BVLD) were immobilized in an organic phytic acid (PA) coating on Mg by an in situ chemical route. Such a drug-loaded PA coating was designed to enhance both corrosion control and biocompatibility. It was found that both Hep- and BVLD-loaded PA coatings exhibited a dual role in effectively controlling corrosion as well as providing a biofunctional effect. Experiments involving electrochemical corrosion and in vitro degradation by immersion revealed that PA&Hep- and PA&BVLD-coated Mg had the same effect or even slower corrosion/degradation in phosphate buffered saline compared to PA-coated Mg, and it degraded significantly slower than untreated Mg. Moreover, Hep- or BVLD-loaded PA coatings showed relatively good hemocompatibility, with a prolonged clotting time, inhibited platelets adhesion as well as reduced hemolysis compared to untreated Mg. In addition, both PA&Hep and PA&BVLD coatings promoted endothelial cells growth and restrained the proliferation of smooth muscle cells. In vivo assays indicated that PA&Hep-coated Mg exhibited a significant difference in mass loss compared to untreated Mg, as well as better histocompatibility than other samples. These results demonstrate that our coating strategy shows a great potential in surface modification of biodegradable Mg. Finally, the mechanism for the incorporation of the drugs into the PA coating is discussed from both theoretical and practical perspectives. [ABSTRACT FROM AUTHOR]

ABSTRACT Magnesium as well as its alloys appears increasingly as a revolutionary bio-metal for biodegradable implants application but the biggest challenges exist in its too fast bio-corrosion/degradation. Both corrosion-controllable and bio-compatible Mg-based bio-metal is highly desirable in clinic. In present work, hexamethylenediaminetetrakis (methylenephosphonic acid) [HDTMPA, (H2O3P−CH2)2−N−(CH2)6−N−(CH2−PO3H2)2], as a natural and bioactive organic substance, was covalently immobilized and chelating-deposited onto Mg surface by means of chemical conversion process and dip-coating method, to fullfill dual-task performance of corrosion-protective and osteo-compatible functionalities. The chemical grafting of HDTMPA molecules, by participation of functional groups on pretreated Mg surface, ensured a firmly anchored base layer, and then sub-sequential chelating reactions of HDTMPA molecules guaranteed a homogenous and dense HDTMPA coating deposition on Mg substrate. Electrochemical corrosion and immersion degradation results reveal that the HDTMPA coated Mg provides a significantly better controlled bio-corrosion/degradation behavior in phosphate buffer saline solution as compared with untreated Mg from perspective of clinic requirement. Moreover, the HDTMPA coated Mg exhibits osteo-compatible in that it induces not only bioactivity of bone-like apatite precipitation but also promotes osteoblast cells adhesion and proliferation. Our well-controlled biodegradable and biocompatible HDTMPA modified Mg might bode well for next generation bone implant application. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 1640-1652, 2015. [ABSTRACT FROM AUTHOR]

Angelica sinensis (AS) and Chuanxiong rhizoma (CR) are frequently prescribed in clinical settings for their ability to enrich blood, regulate menstrual cycles, and alleviate pain. Despite their widespread use, there is a relative dearth of studies exploring their anti-inflammatory properties. To evaluate the antioxidant and anti-inflammatory effects of Angelica sinensis - Chuanxiong rhizoma (ASCR) extracts and investigate its anti-inflammatory mechanisms. AS and CR were combined in six ratios and extracted using five solvents. The quality of the resulting ASCR extracts was assessed by determining the content of ferulic acid (FA) using HPLC. The antioxidant effects of the ASCR extracts were evaluated in vitro using the DPPH and ABTS assays, as well as in HUVECs exposed to H 2 O 2 -induced oxidative damage. Additionally, the anti-inflammatory effects of the extracts were investigated in vivo through the assays of ear edema in mice and paw edema in rats. Biochemical markers including NO, MDA, and SOD in paw tissues, as well as PGE2, TNF-α, and COX-2 in rat serum, were measured to further elucidate the anti-inflammatory mechanisms of ASCR extracts. The WA-2-1 was obtained by combining AS and CR in a 2:1 ratio through first water then ethanol extraction, and showed favorable antioxidant and anti-inflammatory activities. The extract demonstrated effective scavenging abilities against DPPH• and ABTS+• radicals while also protecting against H 2 O 2 -induced oxidative damage. Furthermore, in vivo studies revealed that WA-2-1 had significant inhibitory effects on ear and paw edema as well as the ability to decrease NO and MDA levels, enhance SOD activity, and downregulate the expression of COX-2, PGE2, and TNF-α. The combination of AS and CR exhibits favorable anti-inflammatory effects, attributed to its dual actions of mitigating oxidative stress and suppressing the production of inflammatory mediators in serum or tissues during the inflammatory process. [Display omitted] • The Angelica sinensis-Chuanxiong rhizoma (ASCR) extracts exhibited obvious antioxidant and anti-inflammatory abilities. • The quality of ASCR extracts was assessed by the content of ferulic acid using HPLC. • The preferred WA-2-1 decreased NO and MDA, increased SOD in tissues, and decreased COX-2, PGE2, and TNF-α in serum. • The anti-inflammatory mechanism is related to reducing oxidative stress and inhibiting inflammatory mediators. [ABSTRACT FROM AUTHOR]