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Mixing involves blending raw rubber or masticated rubber with additives using a rubber mixer, which is the most critical process in rubber production. The internal mixer, as the most important mixing equipment, experiences rotor wear during prolonged operation, affecting the gap between the mixer rotor and the chamber wall. This wear reduces mixing effectiveness, weakens filler dispersion, and ultimately impacts rubber performance. In recent years, as research on multi-walled carbon nanotubes (MWCNTs) and nanomaterials has deepened, their broad application prospects have become increasingly apparent. The objective of the present study is to understand and quantify rotor wear in rubber blends during the mixing process as influenced by multi-walled carbon nanotubes. This study found that with the increase in MWCNT content, the proportion of abrasive wear rises, while the proportion of corrosive wear decreases, leading to reduced overall wear. Compared to rubber without MWCNTs, the Payne effect decreased by 6.78%, 9.57%, 13.03%, 20.48%, and 26.06% with the addition of 1 phr, 3 phr, 5 phr, 7 phr, and 9 phr of MWCNTs, respectively. The friction coefficients between the rubber and metal increased by 6.31%, 8.57%, 25.43%, 39.31%, and 47.61%, while the metal wear rate decreased by 9.08%, 10.73%, 13.41%, 17.46%, and 25%. Conversely, the friction coefficients were reduced by 19.39%, 22.42%, 33.94%, 66.06%, and 76.36%. [ABSTRACT FROM AUTHOR]

Purpose: The fibrinogen-to-albumin ratio (FAR) is a novel inflammation marker associated with various diseases. This study aimed to investigate the correlation between FAR and early neurological deterioration (END) after intravenous thrombolysis (IVT) in patients with acute ischemic stroke (AIS). Patients and Methods: From September 1, 2021, to March 31, 2023, continuously recruited AIS patients who received IVT within 4.5 hours were included in the study. Blood samples were collected in the emergency room before IVT. The National Institutes of Health Stroke Scale (NIHSS) score was assessed upon admission and after thrombolysis within the first 24 hours. END was defined as an increase in the NIHSS score by ≥ 4 points within 24 hours after thrombolysis. Multivariate logistic regression analysis was conducted to explore the relationship between FAR and END, and a receiver operating characteristic (ROC) curve was used to evaluate the predictive ability of FAR for END. Results: 343 participants were recruited, and 59 (17.2%) experienced END. Patients with END had higher FAR levels than those without END (P< 0.001). Multivariate logistic regression analysis showed that FAR was independently associated with END, both as a continuous variable and as a tertile variable (P< 0.005). After excluding patients with hemorrhagic transformation (HT), FAR remained independently associated with END (P< 0.005). The area under the curve (AUC) of FAR for predicting END was 0.650 (95% CI=0.571– 0.729, P< 0.001), with an optimal cutoff of 72.367 mg/g, a sensitivity of 61.6%, and a specificity of 62.6%. Conclusion: FAR upon admission was independently associated with END after IVT and can be an effective predictor. [ABSTRACT FROM AUTHOR]

ZrO2–Y2O3 composites with different content of Al2O3–Yb2O3 additives were fabricated by spark plasma sintering (SPS). The effect of Al2O3 and Yb2O3 additives on the mechanical performance, phase transformation, thermal shock resistance and microstructure of ZrO2–Y2O3 composites was researched. The addition of Al2O3 and Yb2O3 contributed to enhancing the phase transformation and densification of ZrO2–Y2O3 composites fabricated by SPS. ZrO2–Y2O3 composites possessed the optimum comprehensive performances as the content of Al2O3 and Yb2O3 is 10 and 4 wt %, respectively. The thermal shock resistance (TSR), hardness, toughness, strength and relative density could achieved of 344°C, 13.6 GPa, 5.7 MPa m1/2, 900 MPa, and 99.5%. The combination of refinement of grain size, changing of fracture mode, enhancement of density, phase transformation contributed to the improvement in TSR and mechanical performances of ZrO2–Y2O3 composites fabricated by SPS. [ABSTRACT FROM AUTHOR]

The rapid nucleic acid extraction is essential, particularly the communicable diseases pandemic. In this work, aluminum modified Fe3O4 (Fe3O4@Al3+) particles were successfully synthesized by solvthermal method, epoxidation, covalent binding of iminodiacetic acid and Al3+ ions coordination for DNA extraction. Fe3O4@Al3+ particles could greatly improve the efficiency of DNA extraction and the extraction could be totally completed within 15 minutes at the optimum condition. The simple and rapid method is mainly based on the Fe3O4@Al3+ particles, which have large specific surface area, superparamagnetism, and Al3+ ions affinity to DNA. Additionally, several characterizations were carried out to further investigate the features of Fe3O4@Al3+ particles. According to SEM image, the average dimension of monodispersed Fe3O4@Al3+ spheres was around 200 nm. XPS results showed the existence of Al3+ on the surface of Fe3O4 particles, which further demonstrated the success of metal chelation in this material synthesis. The XRD patterns indicated that the Fe3O4@Al3+ particles were the inverse spinel structure as the bare Fe3O4 particles. Good magnetism of Fe3O4@Al3+ particles determined by VSM indicated that this material could be easily separated from the reaction system. To summarize, Fe3O4@Al3+ particles is expected to play an important role in future DNA extraction due to remarkable performance. The DNA separation media Fe3O4@Al3+ particles were successfully synthesized. DNA adsorption was effectively achieved by Fe3O4@Al3+ particles based on metal chelation. DNA extraction was significantly boosted by Fe3O4@Al3+ particles. [ABSTRACT FROM AUTHOR]

This paper aims to experimentally investigate the effect of graphene nanoplatelets (GNPs) doped Al2O3 coating deposited on the surface of cemented carbide substrate using suspension high velocity oxy fuel (SHVOF) thermal spraying technique. Scanning electron microscopy was applied to characterize GNPs doped Al2O3 feedstock, the surface morphologies of cemented carbide before and after spraying, and the wear track morphology of cemented carbide after wear tests. The phases of GNPs doped Al2O3 feedstock, uncoated and coated cemented carbide were analyzed by X‐ray diffraction. The existence of GNPs was analyzed by Raman spectroscopy. A mixture of un‐molten and molten splats formed on the surface of cemented carbide substrate after SHVOF thermal spray. The average coefficient of friction (CoF) of coated samples was slightly lower than that of uncoated samples, which might be due to the friction‐reduction effect of GNPs. The wear rate of the samples was one order of magnitude higher than that of the alumina ball, showing that the wear of samples was the main wear between the friction couples. The wear mechanism of uncoated sample was mainly fatigue spalling, and that of cemented carbide substrate coated with GNPs doped Al2O3 coating was mainly plowing and abrasive wear. [ABSTRACT FROM AUTHOR]

An electrochemiluminescence (ECL) aptasensor was prepared to detect Pb2+ with nitrogen-doped carbon quantum dots (NCQDs) as ECL materials. To prepare the working electrode, NCQDs with carboxyl groups were loaded on a glassy carbon electrode (GCE) and then Pb2+ aptamers were covalently bound to the NCQDs to form a stable GCE/NCQDs/aptamers. On addition of Pb2+, the chain aptamers change to a pb2+ G-quadruplex conformation, which lead to a large decrease in the ECL intensity. The variation of intensity and the logarithm of the Pb2+ concentration had a good linear relationship (R2 = 0.998). The detection range was wide (50 pM to 387.9 nM) with a low detection limit (18.9 pM). In interference experiments, the ECL Pb2+ aptasensor did not suffer from interference and it had good stability. The NCQDs ECL aptasensor can detect Pb2+ quickly and accurately, and provides a fast and efficient method for detection of Pb2+. Compared with literatures, the Pb2+ aptasensor has simpler preparation process, lower cost; furthermore, it is more environmentally friendly. [ABSTRACT FROM AUTHOR]

Effective quench detection technologies are extremely important for protecting high temperature superconducting (HTS) applications. In recent years, an optical fiber encapsulated HTS tape (OF-tape) is proposed for quench detection by using distributed temperature sensing (DTS) technology. In this paper, an HTS coil (OF-coil) wound with a 39 m long OF-tape was prepared and energized by an AC overcurrent of 700 A to verify the feasibility of temperature observation during quench events. Furthermore, anti-stokes intensity was also measured to understand dependence of temporal resolutions on response times of coil quenches. The main results show that temperature variations of the OF-coil can be correctly measured after quench and the maximum temperature is shown at the middle turn of the OF-coil. Particularly, for the method of detecting anti-stokes intensity, quench response time of temporal resolution (TR.) with 30 ms is about 500 ms faster than that with 300 ms. However, when the TR. is 30 ms, more noise signal is observed. Accordingly, a trade-off should be considered between response time and noise signal for efficient quench detection. [ABSTRACT FROM AUTHOR]

The biological activity, biocompatibility, and corrosion resistance of implants depend primarily on titanium dioxide (TiO2) film on biomedical titanium alloy (Ti6Al4V). This research is aimed at getting an ideal temperature range for forming a dense titanium dioxide (TiO2) film during titanium alloy cutting. This article is based on Gibbs free energy, entropy changes, and oxygen partial pressure equations to perform thermodynamic calculations on the oxidation reaction of titanium alloys, studies the oxidation reaction history of titanium alloys, and analyzes the formation conditions of titanium dioxide. The heat oxidation experiment was carried out. The chemical composition was analyzed with an energy dispersive spectrometer (EDS). The results revealed that titanium dioxide (TiO2) is the main reaction product on the surface below 900°C. Excellent porous oxidation films can be obtained between 670°C and 750°C, which is helpful to improve the bioactivity and osseointegration of implants. [ABSTRACT FROM AUTHOR]

The laminated Al 2 O 3 –ZrB 2 –MgO/Al 2 O 3 –TiN–MgO (AZTM) ceramic composites were fabricated by hot-press sintering technology. The mechanical properties, microstructures and fracture behaviors of the laminated AZTM ceramic composites, were investigated comprehensively from the micro and macro scale perspectives. The residual stresses, R -curve behaviors and displacement in the laminated AZTM ceramic composites were calculated and analyzed. Compared to the monolithic Al 2 O 3 –TiN ceramic composite, the remarkable improvement in the fracture toughness of the laminated AZTM ceramic composite was obtained. Micro and macro crack deflection, crack bifurcation, bridging toughening and serrated propagation were helpful to the enhancement of the fracture toughness. An intracrystalline/intergranular mixed microstructure, as well as the combination of intergranular failure and transgranular failure contributed to the improvement of the flexural strength for the laminated AZTM ceramic composite. [ABSTRACT FROM AUTHOR]

The comprehensive effect of the mechanical properties, laminated structure and healing conditions on the self-healing behaviors of laminated Al 2 O 3 -MgO ceramic composites was researched. The flexural strengths before and after healing at the temperatures of 715, 815 and 915 °C for 30 min, 60 min and 90 min were measured. According to recovering rate the best healing condition was 900 °C for 60 min. The crack-healing ability of the laminated Al 2 O 3 -MgO ceramic composites was improved due to the enhancement of the original flexural residual effect and the oxide content effect by the elimination of pores and the filling of cracks. In addition, the factors influencing the original flexural residual effect and the oxide content effect were analyzed. Meanwhile, the effects of the particle size and the healing temperature on the healing ability were analyzed qualitatively based on the healing of a single particle model. [ABSTRACT FROM AUTHOR]

Superparamagnetic Fe3O4hollow sub-microspheres (FHSM) with strong response to an external magnet were prepared via a solvothermal method, followed by acid etching. Lipase fromCandidasp. 99–125 was directly immobilized onto the amino-functional FHSM by simple adsorption, without glutaraldehyde linkage. The immobilized lipase was used to catalyze the esterification/transesterification of waste cooking oil with methanol to produce fatty acid methyl ester (FAME), a major source of biodiesel. FAME yield exceeded 93.4% over a wide range of temperatures from 10 to 40 °C. Notably, stability was clearly improved at the lower temperatures, in particular, giving a FAME yield of 89.6% after eight cycles of use at 10 °C. [ABSTRACT FROM PUBLISHER]