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A lubricating oil additive for armored vehicle engine was synthesized by ultrasonic dispersion and physical blending with polyisobutylene and poly alpha olefin as polymer matrix, nanoBN and nanoALN as antifriction materials and polyisobutylene succinimide as surfactant. Polymer-based lubricating oil additive, hydroxyl magnesium silicate powder additive, commercial anti-wear repairing agent Goldway and commercial anti-wear protective agent Chief were dispersed into 10W-40 armored vehicle engine special lubricating oil according to a certain mass fraction. The dissolution stability of different lubricating oil additives in lubricating oil was investigated by standing test. The effects of ultrasonic time and temperature on the dispersion of different kinds of lubricating oil additives in lubricating oil are investigated by using ultrasonic disperser and particle size analyzer. The MDW-5G multifunctional end-face friction and wear tester is used to simulate the actual working process of cylinder liner-piston ring in armored vehicles during driving, and tribological tests were carried out under conventional working conditions to evaluate the tribological properties of different lubricating oil additives. Scanning electron microscope was used to measure and analyze the wear surface morphology and friction interface elements after tribological test, and the lubrication mechanism of lubricating oil additives is revealed. The results show that the polymer-based lubricating oil additive has good dissolution stability and dispersion in lubricating oil. Compared with pure lubricating oil, the average friction coefficient of lubricating oil containing 3wt% polymer-based additives is 0.085, and the friction coefficient decreases by 38.8%. During the friction process, polymer-based lubricating oil additives form a self-repairing oil film to cover the surface of the sample through a series of complex physical and chemical reactions, which reduces the friction and wear between the grinding pairs and improves the lubricating performance of lubricating oil.

Recently, the Muon g-2 experiment at Fermilab has measured the muon anomalous magnetic dipole moment (MDM), $a_\mu=(g_\mu-2)/2$, which reported that the new experimental average increases the tension between experiment and the standard model (SM) prediction to 4.2$\sigma$. In this work, we reanalyse the muon anomalous MDM at two-loop level in the $\mu$ from $\nu$ Supersymmetric Standard Model ($\mu\nu$SSM) combined with the updated experimental average. The $\mu\nu$SSM can explain the current tension between the experimental measurement and the SM theoretical prediction for the muon anomalous MDM, constrained by the 125 GeV Higgs boson mass and decays, the rare decay $\bar{B}\rightarrow X_s\gamma$ and so on. We also investigate the anomalous MDM of the electron and tau lepton, $a_e=(g_e-2)/2$ and $a_\tau=(g_\tau-2)/2$, at two-loop level in the $\mu\nu$SSM. In addition, the 125 GeV Higgs boson decays to a pair of charged leptons in the $\mu\nu$SSM are also analysed., Comment: 26 pages, 10 figures, to be published in Chinese Physics C. arXiv admin note: text overlap with arXiv:2011.04281

Three pairs of enantiomeric sesquiterpenoids, (∓)-syringanoid A (1a and 1b) and (±)-pinnatanoids A (2a and 2b) and B (3a and 3b), that represent an unprecedented 5/4/6 tricyclic backbone and a rare 6/7 bicyclic backbone, respectively, were isolated from the peeled stems of Syringa pinnatifolia. The structures were elucidated by extensive spectroscopic analysis, single-crystal X-ray diffraction, a modified Mosher's method, and quantum chemical calculations. A plausible biotransformation pathway for 1-3 was proposed, and their cardiomyocyte-protective and anti-inflammatory activities were evaluated.

Plant immune signaling largely relies on post-translational modifications to establish a rapid and appropriate defense response to different pathogen types and infection pressure. Specific pleiotropic drug resistance (PDR) transporters can transport secondary metabolites to contribute to pathogen invasion resistance. However, the establishment of the post-translational regulation of PDR transporters that efflux secondary metabolites is unclear. In this study, by detecting the camalexin contents on the leaf surfaces of mutants and overexpression lines, two AGC kinases, namely, OXI1 and its closest homologue AGC2-2, were found to be related to extracellular camalexin secretion. The overexpression of OXI1 or AGC2-2 resulted in an increase in camalexin contents on the leaf surface and a decrease in camalexin contents in the leaf interior. These effects increased the resistance of the transgenic lines to surface-inoculated Pseudomonas syringae and Botrytis cinerea. Through in vitro kinase assay and in vivo phosphorylation level detection, we confirmed that the two kinases were related to the phosphorylation modification of PDR6. Pull-down assays, bimolecular fluorescence complementation, and rapamycin-dependent delocalization assays indicated the existence of direct protein–protein interaction between the two kinases and PDR6. By using LC–MS/MS, we also identified the PDR6 phosphorylation sites that were modified by the two kinases in vitro. Through the expression of the dephosphorylated variants of PDR6 in the mutant background, the action site S31 of OXI1 and the action sites S33 and S827 of AGC2-2 were found to have positive effects on the efflux activity of PDR6. In addition, T832, the action site of OXI1, may contribute to the stability of PDR6 on the plasma membrane.

The difference between the updated experimental result on the muon anomalous magnetic dipole moment and the corresponding theoretical prediction of the standard model on that is about $4.2$ standard deviations. In this work, we calculate the muon anomalous MDM at the two-loop level in the supersymmetric $B-L$ extension of the standard model. Considering the experimental constraints on the lightest Higgs boson mass, Higgs boson decay modes $h\rightarrow \gamma\gamma,\;WW,\;ZZ,\; b\bar b,\;\tau\bar\tau$, B rare decay $\bar B\rightarrow X_s\gamma$, and the transition magnetic moments of Majorana neutrinos, we analyze the theoretical predictions of the muon anomalous magnetic dipole moment in the $B-L$ supersymmetric model. The numerical analyses indicate that the tension between the experimental measurement and the standard model prediction is remedied in the $B-L$ supersymmetric model., Comment: 22pages, 8figures

To solve the μ problem and generate three tiny neutrino masses in the MSSM, the μ from ν Supersymmetric Standard Model (μνSSM) introduces three singlet right- handed neutrino superfields, which lead to the mixing of the Higgs doublets with the sneutrinos. The mixing affects the lightest Higgs boson mass and the Higgs couplings. The present observed 95% CL upper limit on signal strength of the 125 GeV Higgs boson decay h → Zγ is 6.6, which still is plenty of space to prove the existence of new physics. In this work, we investigate the signal strength of the 125 GeV Higgs boson decay channel h → Zγ in the μνSSM. Besides, we consider the two-loop electroweak corrections of muon anomalous magnetic dipole moment (MDM) in the model, which also make important contributions compared with one-loop electroweak corrections.

It is of real and direct significance for China to cope with oil price fluctuations and ensure oil security. This paper aims to quantitatively analyze the specific contribution ratios of the complex factors influencing international crude oil prices and to establish crude oil price models to forecast long-term international crude oil prices. Six explanatory influential variables, namely Dow Jones Indexes, the Organization for Economic Cooperation and Development oil stocks, US rotary rig count, US dollar index, total open interest, which is the total number of outstanding contracts that are held by market participants at the end of each day, and geopolitical instability are specified, and the samples, from January 1990 to August 2017, are divided into six sub-periods. Moreover, the co-integration relationship among variables shows that the contribution ratios of all the variables influencing Brent crude oil prices are in accordance with the corresponding qualitative analysis. Furthermore, from September 2017 to December 2022 outside of the sample, the Vector Autoregressive forecasts show that annually averaged Brent crude oil prices for 2017–2022 would be $53.0, $61.3, $74.4, $90.0, $105.5, and $120.7 per barrel, respectively. The Vector Error Correction forecasts show that annual average Brent crude oil prices for 2017–2022 would be $53.0, $56.5, $58.5, $60.7, $63.0 and $65.4 per barrel, respectively.

The public health and ecological impacts of volatile organic compound (VOCs) pollution have become a serious problem in China, arousing increasing attention to emissions control. In this context, this paper analyses the effectiveness of VOC reduction policies, namely pollution charges and environmental taxes at the national and industrial sector levels. It uses a computable general equilibrium model, which connects macroeconomic variables with VOC emissions inventory, to simulate the effects of policy scenarios (with 2007 as the reference year). This paper shows that VOC emissions are reduced by 2.2% when a pollution charge equal to the average cost of engineering reduction methods – the traditional approach to regulation in China – is applied. In order to achieve a similar reduction, an 8.9% indirect tax would have to be imposed. It concludes that an environmental tax should be the preferred method of VOC regulation due to its smaller footprint on the macroeconomy. Other policies, such as subsidi...

Ab initio methods based on density functional theory at B3LYP level have been applied in investigating the equilibrium geometries, growth patterns, relative stabilities, and electronic properties of Zr2-doped Si n clusters. The optimisation results shown that the lowest-energy configurations for Zr2Si n clusters do not keep the corresponding silicon framework unchanged, which reflects that the doped Zr atoms dramatically affect the most stable structures of the Si n clusters. By analysing the relative stabilities, it is found that the doping of zirconium atoms reduces the chemical stabilities of silicon host. The Zr2Si4 and Zr2Si7 clusters are the magic numbers. The natural population and natural electronic configuration analyses indicated that the Zr atoms possess positive charge for n=1–6 and negative charge for n=7–11. In addition, the chemical hardness, chemical potential, infrared, and Raman spectra are also discussed.

The discrete analogue of the Noether-type identities in eld theory is investigated by means of the di erence discrete variational principle in which the di erence is regarded as an entire geometric object. The discrete counterparts of the Noether theorems are obtained. It is proved that there exists the discrete version of the Noether conservation law in eld theory. The discretization for the nonlinear Schrodinger equation is presented to illustrate the results.

In this paper, we propose a novel steganographic method, which utilizes the sparsity and integrity of the image compressed sensing to reduce the risk of being detected by steganalysis. In the proposed algorithm, the message hiding process is integrated into the image sparse decomposition process without affecting the image perceptibility. First, the cover image is decomposed by the orthogonal matching pursuit algorithm of image sparse decomposition, and the shuffled frog leaping algorithm (SFLA) is used to select the optimal atom in each decomposition iteration. Then, different quantization bits are adopted to quantify the sparse decomposition coefficients. Finally, via LSB[Formula: see text] steganographic strategy, the secret message is embedded in the least significant bits of the quantized coefficients. Experimental results show that the embedded data are invisible perceptually. Simultaneously, experiments show that the new steganography has good expandability in embedding capacity, owing to less sensitivity to the embedding bits. The security of the proposed method is also evaluated comparatively, by using four steganalyzers with rich feature, which indicates superior performance of the proposed method comparing with other steganographies conducted in sparse decomposition domain and the LSB[Formula: see text] methods used in spatial domain and DCT domain.