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In EV/HEV application, the maximum internal temperature allowed for film capacitor should be less than 105 ℃, which leaves especial limited temperature margin as the capacitor works in high ambient temperature of 85 ℃. However, temperature rising of capacitor is strongly related to the load condition. And it is difficult to define the temperature allowance of capacitor accurately in the early design. For this purpose, a consolidated electrothermal simulation method based Foster thermal network model is presented in this paper to predict the transient temperature inside the capacitor. To set up a complete simulation model, the parameters of five-order Foster resistor-capacitor thermal network model are extracted by the method of capacitor temperature rise experiment. The temperature rising of film capacitor in the conditions of NEDC (New European Driving Cycle) & USA highway driving cycle is calculated by the complete simulation model. Simulation results show that a good correspondence is presented between capacitor temperature rising curve vs ripple current under driving cycle, and the maximum temperature rise can be clearly assessed by this temperature prediction method.

In the field of cement, if the formation cannot be given sufficient pressure to maintain stability during construction, pressure control failure may occur, leading to the leakage of liquids and gasses from the formation to the wellbore. In addition, irregular wellbore diameter and casing eccentricity are important factors that are easily overlooked and affect the prediction of ECD (Equivalent Circulation Density) calculation. This results in major accidents and ecological disasters, further impacting the global environment. This study focuses on a well in the eastern oilfields of China, and based on a rheological experiment of high temperature and high pressure, an irregular eccentric wellbore model is established according to the measured wellbore diameter and eccentricity data to calculate the ECD of the whole cementing process. Then, a data set is constructed and analyzed using the random forest method to quantitatively evaluate influencing factors such as displacement, rheology, density, and eccentricity on the bottomhole and wellbore ECD. Results find that the density of cement slurry and drilling fluid has the most significant impact on the maximum ECD, with the impact reaching 0.3142 and 0.2902, respectively, and the main factors that affect the minimum ECD are the density and rheological changes in the drilling fluid, reaching 0.7014 and 0.2846. These research findings will contribute to the precise control of wellbore pressure during cementing operations, further ensuring the safety of cementing operations, and laying a technical foundation for the automation and intelligentization of subsequent cementing operations. [ABSTRACT FROM AUTHOR]

Cordyceps militaris solid medium polysaccharides (CMMPs) were extracted using an ultrasound-assisted enzyme method, and the process conditions were optimized via response surface methodology (RSM). The CMMPs were separated into four components named CMMP−1, CMMP−2, CMMP−3 and CMMP−4 using ethanol fractional precipitation, and their monosaccharide composition and structural properties were analyzed by molecular weight analysis, Fourier-transform infrared spectroscopy (FT–IR), scanning electron microscopy (SEM), Congo red test, ultraviolet–visible spectroscopy (UV-vis), atomic force microscopy (AFM), and thermogravimetric analysis (TGA). RSM could predict the yield of the CMMP (R2 = 0.9928), and the polysaccharide yield was 15.43% under the selected conditions of 3.1% cellulase enzyme addition, a liquid–solid ratio of 42:1, an extraction temperature of 61 °C, and an extraction time of 60 min. Glucose and galactose were the main constituents of the four fractional precipitated polysaccharides. Furthermore, four components exhibited antioxidant activity, and CMMP−1 demonstrated stronger antioxidant activity in vitro. This study demonstrates the possibility of developing a natural antioxidant food from Cordyceps militaris solid medium. [ABSTRACT FROM AUTHOR]

This article was designed to explore the effects and mechanisms of miR-185-5p on the replication of hepatitis C virus (HCV). Quantitative reverse transcription PCR (qRT-PCR) was performed for detecting the abundance of miR-185-5p and HCV RNA in HCV-infected primary hepatocytes and Huh7.5 cells. Dual-luciferase reporter gene assay was used for exploring the interaction between miR-185-5p and GALNT8. Western blot analyzed protein expression of GALNT8, NS3, and NS5A. miR-185-5p was remarkably downregulated in HCV-infected primary hepatocytes and Huh7.5 cells. miR-185-5p upregulation inhibited HCV RNA expression, while its inhibition promoted HCV replication. miR-185-5p induced accumulation of NS3 and NS5A in the cells. Dual-luciferase reporter gene assay verified the targeted relationship between miR-185-5p and GALNT8. In addition, the effects of overexpressing or knocking down miR-185-5p on HCV replication could be correspondingly eliminated by the overexpression or knockdown of GALNT8. miR-185-5p may target GALNT8 in JFH1-infected Huh7.5 cells and then inhibit HCV replication. miR-185-5p may be a potential target for treating HCV.

Exploring and discovering various types of skyrmions has enriched the fundamental study and the active skyrmionics aiming at using skyrmions in spintronics due to the advantages of global stability as high-density magnetic information bit. The unique capability to introduce abundant spin structures, physical phenomena, and dynamics due to the interactions of 4f and 3d electrons push the rare-earth–transition metal (RE–TM) magnets into the research frontier again. Herein, the exotic magnetic domain configurations are discovered in traditional ThMn12-type RE–TM magnets. It is clearly demonstrated that the magnetic anisotropy alteration and magnetic coupling between the respective RE and TM sublattices are responsible for the abundant magnetic domain evolution. In particular, the field-free biskyrmions at room temperature and tunable spin texture transformation are successfully obtained via manipulating the in-plane magnetic anisotropy, which has broadened the physical mechanism and application exploration of manipulating ferrimagnetic order to generate topological spin structures in strategic rare-earth magnets. [ABSTRACT FROM AUTHOR]

Exploration and manipulation of topological protected magnetic swirls, such as skyrmion, antiskyrmion, meron, and vortex, holds significance for fundamental research and practical applications in high‐density magnetic information storage and spintronics because of their high storage density and low driven current. This study unveils the existence of field‐free spontaneous (anti)meron chains with a topological charge of ±1/2 in the centrosymmetric rare‐earth magnet Tb6Co2.17Si2.5 via in situ real‐space observation. The spin reorientation transition from in‐plane to uniaxial anisotropy contributes to the spontaneous transformation from straight domain walls to topological (anti)meron chains and to stripe domains along the [110] zone axis during in situ cooling. The study further confirms the critical role of the noncollinear magnetic structure of Tb atoms in the formation of topological (anti)meron chains via real‐space observations, first‐principles calculations, and micromagnetic simulations. The spontaneous topological magnetic texture is strongly correlated with the 4f electrons of rare‐earth atoms, enriching and stimulating alternative generation mechanisms of topological spin textures from emerging rare‐earth magnets, and further applications in spintronics. [ABSTRACT FROM AUTHOR]

Alloying Pt catalysts with transition metal elements is an effective pathway to enhance the performance of oxygen reduction reaction (ORR), but often accompanied with severe metal dissolution issue, resulting in poor stability of alloy catalysts. Here, instead of forming traditional alloy structure, we modify Pt surface with a novel Ni−W dimer structure by the atomic layer deposition (ALD) technique. The obtained NiW@PtC catalyst exhibits superior ORR performance both in liquid half‐cell and practical fuel cell compared with initial Pt/C. It is discovered that strong synergistic Ni−W dimer structure arising from short atomic distance induced a stable compressive strain on the Pt surface, thus boosting Pt catalytic performance. This surface modification by synergistic dimer sites offers an effective strategy in tailoring Pt with excellent activity and stability, which provides a significant perspective in boosting the performance of commercial Pt catalyst modified with polymetallic atom sites. [ABSTRACT FROM AUTHOR]