The aim of the study was to analyze acoustic emission (AE) signals generated in different magnetic fluid sealing processes to estimate the status of the seal. Based on a magnetic fluid rotary sealing ...experimental setup, the AE sensor is respectively attached to the shell at the corresponding position of the seal, and the external pressure is applied to the magnetic fluid seal by a gas supply system. As the pressure gradually increases, the magnetic fluid sealing rings under different pole teeth are gradually broken, and processes such as pressure transfer between the seal stages occur. These processes generate different AE signals, which are collected by the sensors. The results show that the root-mean-square values of AE signals generated at the moment of sealing failure are different from those generated before and after. At the same time, by analyzing the characteristic values of AE signals generated in the whole process, we can infer the time when the rupture begins under different pole pieces and further estimate the status of the magnetic fluid seal. For the first time, this research demonstrates the experimental and data analysis procedures of AE technology for magnetic fluid seals.
•MUC1 directly binds to JNK1 through the MUC1-CD (amino acids 1-45) region.•MUC1 increases the phosphorylation/activation of JNK1 and c-Jun under genotoxic stress.•MUC1 blocks apoptotic response of ...HCT116 cells to DNA damage via JNK1 pathway.
The MUC1 transmembrane glycoprotein is aberrantly overexpressed in diverse human carcinomas and has been shown to inhibit apoptosis induced by genotoxic agents. In the present work, we report that MUC1 binds to and activates JNK1, an important member of the mitogen-activated protein kinases (MAPK) superfamily. The physical interaction between MUC1 cytoplasmic domain (MUC1-CD) and JNK1 was established by GST-pull-down assay in vitro and co-immunoprecipitation assay in vivo. We show that MUC1 activates JNK1 and inhibits cisplatin-induced apoptosis in human colon cancer HCT116 cells. Pharmacological inhibition of JNK or knockdown of JNK significantly reduces the ability of MUC1 to inhibit cisplatin-induced apoptosis. Together, our data indicate that MUC1 can inhibit apoptosis via activating JNK1 pathway in response to genotoxic anticancer agents.
Using a chemically induced transition method, magnetic nanoparticles of γ-Fe 2 O 3 coated by FeCl 3 · 6H 2 O (γ-Fe 2 O 3 /FeCl 3 · 6H 2 O nanoparticles) can be prepared. Surface modification is ...performed using oleic acid. By adding oleic acid during the synthesis, FeCl 3 · 6H 2 O can be replaced to produce nanoparticles of γ-Fe 2 O 3 coated by a monolayer of oleic acid (γ-Fe 2 O 3 /oleic acid nanoparticles). The amount of oleic acid added is sufficient, with the as-prepared sample single γ-Fe 2 O 3 /oleic acid nanoparticles, whereas the as-prepared sample is a mixture of both γ-Fe 2 O 3 /FeCl 3 · 6H 2 O and γ-Fe 2 O 3 /oleic acid nanoparticles. By chemical species analysis, the mass fraction of both the γ-Fe 2 O 3 phase and oleic acid adsorbed can be estimated. These magnetic nanoparticles coated by oleic acid can be considered as effective nanoparticles with an effective density ρ p.e . The ρ p.e reflects the amount of oleic acid chemisorbed on the nanoparticles. A kerosene-based suspension comprising the effective nanoparticles was synthesized. Results for the specific saturation magnetization σ f.s and density ρ f of the suspension confirm the effective particle structure, involving the mass fraction of oleic acid adsorbed and the effective density of the effective particles.
In this paper, the nonlinear optical properties of magnetic nanoparticle colloidal solutions were studied by the Z-scan technique using 25 ps laser pulses at a wavelength of 1064 nm. Our results ...reveal that the formed magnetic nanoparticle clusters under high incident laser intensity will greatly affect the nonlinear optical characteristics of the solution. As the intensity of the pulsed laser decreases, the reverse saturable absorption coefficient and nonlinear refractive index of the sample tend to increase. The evolution of this nonlinear characteristic only occurs in liquid suspension. This is confirmed by fixing particles on a substrate upon which the responses observed in the liquid medium are no longer present. Besides, the possibility of generating optical trapping in the focus of the laser pulses is proposed to explain our experimental results.
The electro-optical features of the PDLC films applied with a low-frequency square wave voltage were investigated. The transmittance curves indicated the double frequency of the applied voltage at ...0–50 Hz, which resulted from the relaxation of an internal electric field polarized by ions in LC droplets. When the local electric field was reversed, the internal polarization electric field could be maintained and superimposed on the local electric field. The relaxation of the internal polarized electric field resulted in the relaxation of the transmittance. Furthermore, the transmittance curves changed with the frequency of the applied voltage.
Most denoising methods are designed to deal standard images with specific type noise, which do not perform well when denoising real noisy images contain uncertain types of noise. However, underwater ...image is a typical uncertain type noise image. To solve this problem, this paper presents a method using spatial feature classification jointing nonsubsampled shearlet transform (NSST) for denoising uncertain type noise images. Justifiable granule is employed to solve the problem of parameter selection. The raw image was decomposed by using the NSST to get one low frequency subband and several high frequency subbands. Then, the preliminary binary map is built, the binary map is employed to decide whether a coefficient contains spatial feature or not. And we employ justifiable granule to solve the difficulty of parameter selection. The high subbands coefficients are classified into two classes by fuzzy support vector machine classification: the texture class and the noise class. At last, the adaptive Bayesian threshold is used to shrink the coefficients. Simulation results show the proposed method is effective in uncertain type noise images(also have good performance in specific type noise). The method we proposed has been compared with other popular denoising methods and get excellent subjective performance and PSNR improvement.
Three types of surfactants (oleic acid, linoleic acid, and a mixture of oleic acid and linoleic acid) were coated on ferromagnetic particles, which were dispersed in kerosene to prepare magnetic ...fluids, to study the effect of different fatty acids as surfactants on the rheological properties of magnetic fluids. The particles were analyzed by XRD, TEM, FT-IR, and VSM. Furthermore, a rheometer was used to examine the rheological properties of kerosene-based magnetic fluids dispersed with various surfactants. The yield stress at different magnetic fields was calculated by fitting the Herschel–Bulkley model. The fitted curve and the observed values of mixed fatty acids are identical. The graphs of viscosity increase with the shear rate for each magnetic fluid were measured at constant magnetic field strengths. At constant shear rates, the curves of viscosity increase with magnetic field intensity were measured. In the absence of a magnetic field, the relative change in viscosity from 40°C to 0°C was observed. The rheological measurements of the mixed fatty acid-dispersed ferrofluid with a rising magnetic field at a constant shear rate are smoother than the single-fatty-acid-dispersed ferrofluid, indicating that it is more stable. As the temperature is dropped, the viscosity–temperature curve evidence that mixed fatty acids as surfactants can lower the proportion of magnetic fluid viscosity rise.
In this research, a new low refractive index ferrofluid is proposed by coating magnetic nanoparticles with a layer of silver, applying the method of modified chemical co-precipitation. This ...preparation method is green and environmentally friendly without toxic gases being released. Coated nanoparticles are characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive X-ray spectrometry (EDS), X-ray photoelectron spectroscopy (XPS), and vibration sample magnetometery (VSM). These characterizations show that the silver nanoparticles grow on the surface of magnetic nanoparticles in this new ferrofluid. The hysteresis loop of this new ferrofluid demonstrates that it maintains superparamagnetic properties. A new method of refractive index measurement is applied in this research by employing a long-period grating (LPG) optical fiber sensor. The change value in the refractive index per unit concentration reduces by 16.46% compared to the conventional ferrofluid.
In this paper, we selected representative electric buses (EBs) and diesel buses as research cases, aiming to explore a localized method suitable for various vehicle types that can be implemented in ...any region to measure the carbon emissions of urban buses throughout the lifecycle. We take into account the influence of seasonal factors over the lifecycle. We fully consider the production, assembly, and recycling stages of vehicle systems. We construct a model for estimating CO2 emissions during the fuel cycle. We analyze and compare the impacts of the optimized power grid structure on the lifecycle CO2 emissions of the two types of buses. The results indicate that seasonal factors affect both bus types' energy consumption, with EBs being more sensitive. Carbon emissions primarily stem from manufacturing the body, chassis, and notably, the lithium‐ion batteries, with the latter having a pronounced impact on EBs. A decrease in coal power generation from 71% to 21% in the grid reduced EB fuel‐cycle emissions by 70.7%. Although EBs are sensitive to seasonal factors, they still have the greatest potential for carbon reduction, depending on the proportion of clean energy in the power grid and the production processes of vehicle components.
This study selected representative electric and diesel buses as case studies to measure the urban buses' carbon emissions throughout their lifecycle, considering seasonal factors and the structure of the electric grid. The results indicate that while electric buses are more sensitive to seasonal factors, and the production of lithium‐ion batteries has a significant impact, they still have the greatest potential for carbon reduction.
Magnetic fluids, a new type of energy transfer fluid with tunable properties, have garnered significant interest from researchers worldwide. Hybrid magnetic fluids prepared by adding different types ...of nanoparticles exhibit superior thermophysical properties and functional characteristics. In this paper, we prepared a water-based magnetic fluid loaded with multi-walled carbon nanotubes (MCNTs), silver (Ag), and copper (Cu) to enhance thermal conductivity. Using a transient double hot-wire method, we designed and built an experimental measurement system for the thermal conductivity of magnetic fluids with an average measurement error of less than 5%. We studied the thermal conductivity of hybrid magnetic fluids under different conditions and evaluated the advantages and disadvantages of various models, including the Maxwell model, H&C model, Tim model, Y&C model, and Evans model. Our results show that MF+MCNTs, MF+Ag, and MF+Cu nanofluids can all improve the thermal conductivity of the carrier fluid, with MF+MCNTs exhibiting the best improvement effect of 10.93%. Among the five models evaluated, the Evans model had the best predictive effect with a deviation range within 5%. This work provides theoretical and practical reference for enhancing the thermal conductivity of magnetic fluids and provides a more accurate theoretical model for calculating the thermal conductivity of hybrid magnetic fluids.
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