Nonequilibrium molecular dynamics (NEMD) simulations were performed to investigate the tribology behaviors of Al
2
O
3
and MoS
2
nanoparticles confined between iron (Fe) slabs. Results indicated that ...the combined use of these two nanoparticles yielded the lowest and most stable friction force, normal force, interface temperature and wear rate, which exhibited a significant synergistic lubrication effect. A novel parameter the rolling/sliding motion coefficient (
K
rs
) was proposed to evaluate the motion pattern of spherical Al
2
O
3
. There were 51% rolling + 49% sliding motion when used alone and 91% rolling + 9% sliding in the existence of MoS
2
. Similarly, about 72.3% of the friction was shared by interlayer sliding of MoS
2
monolayers in the presence of Al
2
O
3
, which was higher than used alone (54.8%). Then, the diffusion of atoms at the friction interface was explored to reveal the synergistic lubrication mechanism. The tribofilm formed by the diffusion of Fe and S atoms could protect the metal surfaces from further wear. The adsorption of S atoms to Al
2
O
3
nanoparticle could promote its rolling effect and prevent it from embedding into iron matrix. Besides, Al
2
O
3
could also facilitate the separation of MoS
2
monolayers to enhance their interlayer sliding effect.
The water-based MoS2 nano-lubricant was prepared and tentatively applied in cold rolling lubricant recirculation systems to investigate its recycling prospect and sustainable lubrication mechanism. ...The tribological properties and rolling lubrication performance of recycled nano-lubricants with different cycle stages were preliminarily evaluated using four-ball tribotester and two-high rolling mills. To determine the phase transformation of MoS2 in recycled nano-lubricants, the already used MoS2 nano-lubricant was collected, dried and then analyzed by means of X-ray diffraction (XRD). Molecular dynamics simulation was conducted to analyze the specialized lubrication mechanism of reused MoS2 nano-lubricant. The results revealed that the MoS2 was considered to gradually transform into MoO3 during cold rolling process. Those oxidizing metamorphic MoS2 nano-lubricants still had excellent friction reducing and wear resistance. That indicated MoS2 nano-lubricant could be recycled in cold rolling process. The recirculation of MoS2 nano-lubricant reduced the use of lubricants, the discharge of waste liquid and the production cost. Not only the pollution to environment was relieved, but also resources and costs were saved. The calculation results of adsorption energy between nanoparticles and steel surface further demonstrated the absorbing type of lubricating film in different cycle stages. A lubrication model suitable for MoS2 nano-lubricants under steel strip cold rolling lubrication circulation condition was established to explain their sustainable lubrication mechanism.
•MoS2 nano-lubricant used in cold rolling process was confirmed to be recyclable.•The existence of recycled MoS2 nano-lubricant improved the quality of rolled surface.•The phase transformation of nano-MoS2 during long time recirculation was studied.•Lattice parameter was calculated to explain the sustainable lubrication performance.•Lubrication film evolution model was established to explain lubrication mechanism.
Guiding institutional investors to actively participate in corporate governance is a hot issue to improve the internal governance of China's listed companies. This study seeks to provide a ...comprehensive understanding of the mechanism that underlies the governance effects of the heterogeneity of institutional investors on the cost of capital, and the influence of ownership structure on the relationship between them. Using an unbalanced panel data on A-share listed companies of Shanghai and Shenzhen in China's capital market during the 2014-2019 period, this study reveals how institutional investors with longer holding period and higher shareholding ratio are negatively associated with the cost of capital in China's capital market. Furthermore, this study successfully confirms the moderating effect of ownership structure in the relationship between institutional investors and the cost of capital. China's state-owned enterprises are more likely to introduce improvements at the corporate governance level, and ownership concentration weakens the negative influence of institutional investors on the cost of capital. The research contributes to a deeper understanding of the impacts of institutional investor's heterogeneity and ownership structure on the cost of capital in China. In the process, the study yields useful implications for the theory and practice of corporate governance.
Based on the broad-spectrum biological activities of echinopsine and acylhydrazones, a series of echinopsine derivatives containing acylhydrazone moieties have been designed, synthesized and their ...biological activities were evaluated for the first time. The bioassay results indicated that most of the compounds showed moderate to good antiviral activities against tobacco mosaic virus (TMV), among which echinopsine (I) (inactivation activity, 49.5 ± 4.4%; curative activity, 46.1 ± 1.5%; protection activity, 42.6 ± 2.3%) and its derivatives 1 (inactivation activity, 44.9 ± 4.6%; curative activity, 39.8 ± 2.6%; protection activity, 47.3 ± 4.3%), 3 (inactivation activity, 47.9 ± 0.9%; curative activity, 43.7 ± 3.1%; protection activity, 44.6 ± 3.3%), 7 (inactivation activity, 46.2 ± 1.6%; curative activity, 45.0 ± 3.7%; protection activity, 41.7 ± 0.9%) showed higher anti-TMV activity in vivo at 500 mg/L than commercial ribavirin (inactivation activity, 38.9 ± 1.4%; curative activity, 39.2 ± 1.8%; protection activity, 36.4 ± 3.4%). Some compounds exhibited insecticidal activities against Plutella xylostella, Mythimna separate and Spodoptera frugiperda. Especially, compounds 7 and 27 displayed excellent insecticidal activities against Plutella xylostell (mortality 67 ± 6% and 53 ± 6%) even at 0.1 mg/L. Additionally, most echinopsine derivatives exhibited high fungicidal activities against Physalospora piricola and Sclerotinia sclerotiorum.
The influence of MoS
2
–Al
2
O
3
nanofluid as a functional lubricant on the microstructure and corrosion resistance of hot-rolled steel surface was studied. Because of the excellent lubrication ...performance of the nanofluid, the rolled surface quality improved with a 18.2% and 69.5% reduction in surface roughness and oxide scale thickness, respectively, when compared with the base-fluid without nanoparticles. The further microstructure characterization determined that the grain size, local misorientation and deformed grain fraction of the steel decreased significantly. A diffusion layer of Al
2
O
3
, FeS and FeMo
4
S
6
was found in the outer oxide layer of rolled surface. Closely arranged Al
2
O
3
grains inhibited the oxidation of steel strips that the oxidation activation energy was increased by about 14.5%. Through density functional theory (DFT) calculation, the formation of FeS and FeMo
4
S
6
was attributed to the migration of Mo and S atoms from MoS
2
into the Fe lattice through substitutional and interstitial diffusion, respectively, with the energy barrier of 0.84 eV and 0.54 eV. Finally, the protection of diffusion layer, reduction in surface defects, and alleviation of residual stress and deformation resulted in the enhancement of corrosion resistance. This study provides a possible route to achieve surface enhancement during the hot rolling process.
Graphical abstract
ROPs (Rho-like GTPases from plants) are a unique family of small GTP-binding proteins in plants and play vital roles in numerous cellular processes, including growth and development, abiotic stress ...signaling, and plant defense. In the case of the latter, the role of ROPs as response regulators to obligate parasitism remains largely enigmatic. Herein, we isolated and identified ShROP7 and show that it plays a critical role in plant immune response to pathogen infection. Real-time quantitative PCR analysis revealed that the expression of ShROP7 was significantly increased during incompatible interactions. To establish its requirement for resistance, we demonstrate that virus-induced gene silencing (VIGS) of ShROP7 resulted in increased susceptibility of tomato to Oidium neolycopersici (On) Lanzhou strain (On-Lz). Downstream resistance signaling through H2O2 and the induction of the hypersensitive response (HR) in ShROP7-silenced plants were significantly reduced after inoculating with On-Lz. Taken together, with the identification of ShROP7-interacting candidates, including ShSOBIR1, we demonstrate that ShROP7 plays a positive regulatory role in tomato powdery mildew resistance.
As a global health problem, liver fibrosis still does not have approved treatment. It was proved that N-(3,4,5-trichlorophenyl)-2(3-nitrobenzenesulfonamide) benzamide (IMB16-4) has anti-hepatic ...fibrosis activity. However, IMB16-4 displays poor water solubility and poor bioavailability. We are devoted to developing biodegraded liposome-coated polymeric nanoparticles (LNPs) as IMB16-4 delivery systems for improving aqueous solubility, cellular uptake, and anti-fibrotic effects. The physical states of IMB16-4−LNPs were analyzed using a transmission electron microscope (TEM), high-performance liquid chromatography (HPLC), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and differential scanning calorimeter (DSC). The results show that IMB16-4−LNPs increased the drug loading compared to liposomes and enhanced cellular uptake behavior compared with IMB16-4−NPs. In addition, IMB16-4−LNPs could repress the expression of hepatic fibrogenesis-associated proteins, indicating that IMB16-4−LNPs exhibited evident anti-fibrotic effects.
Developing high efficient and cheap electrocatalysts for carbon dioxide reduction reaction (CO2RR) is the key to achieve CO2 transformation into clean energy. Herein, a series of transition metal ...dimer and nitrogen codoped graphene (M2N6-Gra, M = Cr–Cu) acting as electrocatalysts for CO2RR are investigated based on the density functional method. For M2N6-Gra (M = Cr, Mn), the selectivity is poor and CO poisoning is serious. Fe2N6-Gra is the best CO2RR catalyst due to the good selectivity and catalytic activity. The calculated overpotential is very small, i.e., 0.03 V for COOH channel, 0.05 V for HCOO channel. Hydrogen evolution reaction is also refrained on the Fe2N6-Gra surface, which further supports its high catalytic performance. For M2N6-Gra (M = Co, Ni, Cu), the catalytic activity is poor due to large overpotentials. These results indicate that if designed carefully, the transition metal dimer and nitrogen codoped graphene would be good candidate for the high efficient and selective CO2RR catalyst.
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•The mechanism of CO2RR on M2N6-Gra (M = Cr–Cu), has been studied by using the DFT.•The studied M2N6-Gra (M = Cr–Cu) is stable thermodynamically.•Fe2N6-Gra exhibits high selectivity and catalytic activity for CO2RR.
Liver fibrosis results from the chronic liver injury and no specific medical therapy is approved so far. Recently, new compound, N-(3,4,5-trichlorophenyl) - 2 (3-nitrobenzenesulfonamido) benzamide, ...referred to as IMB16-4, was developed to resist liver fibrosis. However, IMB16-4 displays poor aqueous solubility and poor oral bioavailability. To increase the dissolution rate, improve the oral bioavailability and enhance the anti-hepatic fibrosis action of IMB16-4, IMB16-4 self-emulsifying drug delivery systems (SEDDS) with negative charge or positive charge were prepared using simple stirring, respectively. Their stability, oral bioavailability and anti-liver fibrosis effect were evaluated. The results showed IMB16-4 SEDDS in simulated gastric juice were nearly spherical with the diameter of 100～200 nm and possessed good stability in 30 days. The oral bioavailability of IMB16-4 SEDDS with negative charge and positive charge were increased to 33 folds and 58 folds compared with that of pure IMB16-4, respectively. In bile duct ligation (BDL) rats, IMB16-4 SEDDS attenuated the degree of liver damage and decreased collagen accumulation. In addition, IMB16-4 SEDDS with negative charge easily accumulated in the liver and alleviated hepatic fibrosis by TGF-β/Smad signaling. These findings indicate that IMB16- 4 SEDDS may be a potential therapy for the treatment of liver fibrosis.
causes fruit or foliar disease called anthracnose on a variety of plant hosts such as vegetables, fruits, ornamental plants, and others, including chili pepper, apple, American cranberry, mango, ...orange, papaya, guava, rubber plant, jasmine, coffee berry, and tea plants. Here, we report the first Illumina-sequenced draft genome assembly of
strain ICMP 18578 and its annotation. This genome sequence provides a unique resource that will be useful for future research on the evolution of
spp. and improvement of anthracnose management strategies.
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