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The interaction between cis-2 bis(benzofuro)[60]fullerene derivative and NO dominated double gas molecule was studied at the 6–311G(d,p) basis set level by density functional theory B3LYP-D3 method. The geometric structures of six interaction systems were optimized, and the optimized configurations were analyzed by electronic properties, infrared chromatography and independent gradient model to reveal the essence of intermolecular interaction. The results shows that NONO2, NON2, NOCO, NOCO2 and NOHCN are co-adsorbed on the surface of the compound in physical form, and the binding energies are −77.62 kJ/mol, −24.24 kJ/mol, −27.43 kJ/mol, −39.28 kJ/mol and −36.29 kJ/mol, respectively. The van der Waals interaction between gas molecules makes the three molecular interaction system have synergistic adsorption or competitive adsorption effect. Among them, the synergistic effect of NONO2 co-adsorption system is the biggest, and there is a strong attraction between NO and NO2 molecules. Compared with the interaction system of single gas molecule with cis-2 bis(benzofuro) [60]fullerene derivative, the interaction intensity of double gas molecule with the derivative is significantly improved.

A flexible rotor supported by two journal bearings under nonlinear suspension and the lubricating oil is assumed to be temperature dependent in this study. Analytical tools were inclusive of bifurcation diagrams, dynamic trajectories, power spectra, Poincaré map, fractal dimension, and Lyapunov exponent are used to verify the dynamic characteristics of the rotor-bearing system, and abundant periodic, subharmonic, quasi-periodic, and even chaotic motions are found in this study. From the simulation results, the higher operating temperature will also cause the dynamic trajectory of the system to become non-periodic vibration. The rotor-bearing system operating in a non-periodic motion state may lead to possible broadband vibration with large amplitude and increase the possibility of fatigue or failure of the system. Such simulation analysis will help engineers avoid unnecessary trial and error when designing and applying rotor-bearing systems.

Abstract Background Rodents are important virus reservoirs and natural hosts for multiple viruses. They are one of the wild animals that are extremely threatening to the spread of human viruses. Therefore, research on rodents carrying viruses and identifying new viruses that rodents carry is of great significance for preventing and controlling viral diseases. Methods In this study, fecal samples from six species of forest rodents in Northeast China were sequenced using metagenomics, and an abundance of virome information was acquired. Selection of important zoonotic in individual rodents for further sequence and evolutionary analysis. Results Among the top 10 most abundant viral families, RNA virus include Orthomyxoviridae, Picornaviridae, Bunyaviridae and Arenaviridae, DNA virus include Herpesviridae, Insect virus include Nodaviridae and Baculoviridae, Plant virus Tombusviridae and Phage (Myoriviridae). Except for Myoviridae, there was no significant difference in the abundance of virus families in the feces of each rodent species. In addition, a new strain of astrovirus was discovered, with an ORF and genome arrangement comparable to other rodent astroviruses.The newly identified astrovirus had the highest similarity with the rodent astrovirus isolate, CHN/100. Conclusions The data obtained in this study provided an overview of the viral community present in these rodent fecal samples, revealing some rodent-associated viruses closely related to known human or animal pathogens. Strengthening our understanding of unclassified viruses harbored by rodents present in the natural environment could provide scientific guidance for preventing and controlling new viral outbreaks that can spread via rodents.

Nuclear magnetic resonance (NMR) magnetometers are considered due to their ability to map magnetic fields with high precision and calibrate other magnetic field measurement devices. However, the low signal-to-noise ratio of low-strength magnetic fields limits the precision when measuring magnetic fields below 40 mT. Therefore, we developed a new NMR magnetometer that combines the dynamic nuclear polarization (DNP) technique with pulsed NMR. The dynamic pre-polarization technique enhances the SNR under a low magnetic field. Pulsed NMR was used in conjunction with DNP to improve measurement accuracy and speed. The efficacy of this approach was validated through simulation and analysis of the measurement process. Next, a complete set of equipment was constructed, and we successfully measured magnetic fields of 30 mT and 8 mT with an accuracy of only 0.5 Hz (11 nT) at 30 mT (0.4 ppm) and 1 Hz (22 nT) at 8mT (3 ppm).

This paper investigated the effects of porous media layer (PML) and couple stress (CS) lubricants at pure squeeze action in an isothermal elastohydrodynamic lubrication (EHL) point contact with surface roughness (SRN) under constant load condition. The modified transient stochastic Reynolds equation was derived in polar coordinates by means of the Christensen’s stochastic theory and the Stokes’s CS fluid theory. The Gauss-Seidel method (GSM) and the finite difference method (FDM) were both used to solve simultaneously modified transient stochastic Reynolds, force equilibrium, elasticity deformation, and rheology equations. The simulation results revealed that the greater permeability ( K ) and porous layer thickness (Φ) are, the smaller central pressures ( P c ) are, and the smaller film thicknesses ( H ) are. The times required for achieving maximum central pressures (Pc max ) decrease with increasing K and Φ. Due to squeeze and elastic deformation effects, the slope values of central velocity ( V c ) change from negative to positive. The magnitude of V c and V min decreased with decreasing K and Φ. The Hcmin of circular type RN are greater than that of radial type RN. The Pc max of radial type RN are slightly greater than that of circular type RN.

A flexible rotor supported by two journal bearings under nonlinear suspension and the lubricating oil is assumed to be temperature dependent in this study. Analytical tools were inclusive of bifurcation diagrams, dynamic trajectories, power spectra, Poincaré map, fractal dimension, and Lyapunov exponent are used to verify the dynamic characteristics of the rotor-bearing system, and abundant periodic, subharmonic, quasi-periodic, and even chaotic motions are found in this study. From the simulation results, the higher operating temperature will also cause the dynamic trajectory of the system to become non-periodic vibration. The rotor-bearing system operating in a non-periodic motion state may lead to possible broadband vibration with large amplitude and increase the possibility of fatigue or failure of the system. Such simulation analysis will help engineers avoid unnecessary trial and error when designing and applying rotor-bearing systems. [ABSTRACT FROM AUTHOR]