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1.
ACS Appl Mater Interfaces ; 13(19): 23057-23066, 2021 May 19.
Article En | MEDLINE | ID: mdl-33945272

To improve thermal barrier applications in advanced vehicle engines, a novel Fe-based amorphous composite coating was designed by introducing ceramic oxides and was prepared by atmospheric plasma spraying (APS). The microstructure and related properties of the as-deposited coating were investigated in detail. The composite coating comprises a well-formed FeCrNbBSi amorphous metallic matrix and dispersed yttria-stabilized zirconia (YSZ) splats. A unique Si-oxide interfacial layer with a thickness of several nanometers and an amorphous structure forms between the metallic matrix and ceramic phase, which is attributed to a combination of multiple effects. The composite coating displays extremely low thermal conductivity from 2.28 W/mK at 100 °C to 3.36 W/mK at 600 °C and can increase the surface temperature of the piston crown by 18.93 °C, which implies a significant means of enhancing the power efficiency. The improved thermal barrier ability of the composite coating is revealed as the crucial effect of the Si-oxide interfacial layer, which induces an increased interfacial thermal resistance. The fracture toughness of the composite coating remains at 3.40 MPa·m1/2, comparable to that of the monolithic amorphous coating, 3.74 MPa·m1/2, which is closely related to the formation of a Si-oxide layer and its nanoscale thickness. Therefore, the Fe-based amorphous composite coating developed here demonstrates great potential as an innovative metal-based thermal barrier coating for application in vehicle engines and provides specific inspiration for future works exploring the interfacial engineering of coating.

2.
Fish Shellfish Immunol ; 67: 312-321, 2017 Aug.
Article En | MEDLINE | ID: mdl-28606860

A 10-week feeding trial was carried out to investigate the effects of dietary fish meal replacement by yeast hydrolysate (YH) on growth performance, complement system and stress resistance of juvenile Jian carp (Cyprinus carpio var. Jian) (initial average weight 19.44 ± 0.06 g). In the study, there were five groups: one control group was fed with a basal diet (YH0), and four treatment groups were fed with dietary fish meal replaced by 1% YH (YH1), 3% (YH3), 5% (YH5) and 7% (YH7), respectively. Each group had four replicates. At the end of feeding trial, twelve fish from each group (three fish per replicate) were randomly selected for assessing the growth and immunity. Meanwhile, 20 fish per replicate were injected by Aeromonas hydrophila. The results showed that (1) Replacement levels of YH significantly affected the growth of the fish with the highest values of weight gain (WG) occurred in fish fed YH3 diet. However, no significant difference in feed conversion ratios (FCR) was observed among all groups. (2) Pre-stressed plasma lysozyme activity, total protein and albumin contents and complement component 3 (C3) and complement component 4 (C4) levels of fish fed YH3 diet were significantly higher than those of fish fed YH0 diet. However, post-stressed immune parameters of fish in all groups were significantly lower. (3) There was a trend that the expression levels of the complement-related genes (c1r/s-A, c4-1, c3-H1, c5-1, fb/c2-A, mbl-2 and masp) initially increased and then decreased except mbl-2 and masp, with the maximum values observed in fish fed YH3 diet. Before stress, the expression levels of the inflammation-related genes (alp, il-1ß and tnf-α) in the hepatopancreas and spleen of fish fed YH1 diet and YH7 diet were significant higher than that of fish fed YH0 diet. After stress, no significant difference in the expression levels of those genes was observed among all groups. These results indicated that FM replacement by YH could improve growth performance, enhance innate immunity, and activate complement via the alternative complement pathway (ACP) and the classical complement pathway (CCP).


Carps/immunology , Dietary Supplements , Immunity, Innate , Saccharomyces cerevisiae , Stress, Physiological/immunology , Animal Feed/analysis , Animals , Carps/genetics , Complement C3/metabolism , Complement C4/metabolism , Diet/veterinary , Fish Proteins/metabolism , Random Allocation
3.
Environ Toxicol Pharmacol ; 39(2): 515-24, 2015 Mar.
Article En | MEDLINE | ID: mdl-25681702

The poor bioavailability and stability of curcumin limit its clinical application. A novel Zn(II)-curcumin complex was synthesized and its effects against cyclophosphamide (CP)-induced reproductive damage were compared with curcumin. Oral administration of Zn(II)-curcumin significantly prevented CP-induced elevation of malondialdehyde (MDA) level and reductions in superoxide dismutase (SOD) activity and glutathione (GSH) content in mouse testis. Zn(II)-curcumin significantly ameliorated CP-induced reductions in body and reproductive organs weights. Zn(II)-curcumin dose-dependently ameliorated CP-induced reproductive system impairments, by improving sperm parameters (sperm count, viability, motility) and reducing serum testosterone and histological alterations. Compared to curcumin at the same dose, Zn(II)-curcumin more effectively alleviated CP-induced reproductive injury, leading to a reduced severity of testicular pathologic changes, lower MDA level, elevated SOD activity and GSH content, and increased sperm parameters and serum testosterone. These results suggest Zn(II)-curcumin more effectively protects against CP-induced reproductive damage than curcumin alone due to a synergistic reduction in oxidative stress.


Antioxidants/pharmacology , Curcumin/pharmacology , Cyclophosphamide/toxicity , Spermatozoa/drug effects , Testis/drug effects , Zinc/pharmacology , Animals , Cell Survival/drug effects , Glutathione/metabolism , Male , Malondialdehyde/metabolism , Mice , Oxidative Stress/drug effects , Sperm Count , Sperm Motility/drug effects , Spermatozoa/cytology , Spermatozoa/physiology , Superoxide Dismutase/metabolism , Testis/pathology , Testosterone/blood
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