Effect of Particle Size on the Wear Property of Magnetorheological Fluid

Aiming to study the effect of particle size on the wear property of magnetorheological fluid (MRF), experiment materials, preparation process, and test methods are elaborated, and three different MRF samples consisting of particles of different size are prepared. Test experiments are carried out and the effect of particle size on the wear property of MRF is discussed. Moreover, the microstructures of particles extracted from MRF obtained before and after the wear experiments are observed by scanning electron microscope (SEM). Experimental results show that the particle size has a significant effect on wear property of MRF. Furthermore, the MRF with particles of 1.5–2.8 μm diameter on average is good for the requirement of engineering applications

Comparative studies of salinomycin-loaded nanoparticles prepared by nanoprecipitation and single emulsion method

To establish a satisfactory delivery system for the delivery of salinomycin (Sal), a novel, selective cancer stem cell inhibitor with prominent toxicity, gelatinase-responsive core-shell nanoparticles (NPs), were prepared by nanoprecipitation method (NR-NPs) and single emulsion method (SE-NPs). The gelatinase-responsive copolymer was prepared by carboxylation and double amination method. We studied the stability of NPs prepared by nanoprecipitation method with different proportions of F68 in aqueous phase to determine the best proportion used in our study. Then, the NPs were prepared by nanoprecipitation method with the best proportion of F68 and single emulsion method, and their physiochemical traits including morphology, particle size, zeta potential, drug loading content, stability, and in vitro release profiles were studied. The SE-NPs showed significant differences in particle size, drug loading content, stability, and in vitro release profiles compared to NR-NPs. The SE-NPs presented higher drug entrapment efficiency and superior stability than the NR-NPs. The drug release rate of SE-NPs was more sustainable than that of the NR-NPs, and in vivo experiment indicated that NPs could prominently reduce the toxicity of Sal. Our study demonstrates that the SE-NPs could be a satisfactory method for the preparation of gelatinase-responsive NPs for intelligent delivery of Sal

Observation of Complete Photonic Bandgap in Low Refractive Index Contrast Inverse Rod-Connected Diamond Structured Chalcogenides

Three-dimensional complete photonic bandgap materials or photonic crystals block light propagation in all directions. The rod-connected diamond structure exhibits the largest photonic bandgap known to date and supports a complete bandgap for the lowest refractive index contrast ratio down to nhigh/nlow ∼ 1.9. We confirm this threshold by measuring a complete photonic bandgap in the infrared region in Sn–S–O (n ∼ 1.9) and Ge–Sb–S–O (n ∼ 2) inverse rod-connected diamond structures. The structures were fabricated using a low-temperature chemical vapor deposition process via a single-inversion technique. This provides a reliable fabrication technique of complete photonic bandgap materials and expands the library of backfilling materials, leading to a wide range of future photonic applications

Effect of thermal history on the deformation of non-metallic inclusions during plain strain compression

The deformation of inclusions in the steel was affected by the thermal history during the physical simulation of steel processing. After plain strain compression with a reduction of 30%, the average aspect ratio of inclusions in the steel sample cooled down to 1673 K from semi-solid state was 1.89, which was significantly higher than 1.29 in the steel sample heated persistently up to the same temperature. The mechanism was revealed by inclusion transformation

Effect of compression reduction on deformation of CaO‐CaS‐Al 2 O 3 ‐MgO inclusions in solid and semi‐solid steel

Plain strain deformation was performed on solid steel samples at 1473 K and semi‐solid samples at 1743 K. The deformation of inclusions under the reductions of 10%, 20%, and 30% was studied. In the solid steel deformed at 1473 K, the average aspect ratio of inclusions increased from 1.23 in the original slab to 2.07, 2.23, and 2.30 under the reduction of 10%, 20%, and 30%. The deformation of inclusions in the semi‐solid steel was hardly influenced by the reduction. The deformation of inclusions was much more in the solid steel than that in the semi‐solid steel in the current study. Inclusion deformation was explained by the difference of hardness between the inclusion phase and the steel matrix. Stress‐strain curves during deformations indicated that the semi‐solid steel matrix at 1743 K was much softer than the solid steel matrix at 1473 K. Compared to the composition of inclusions in the original slab, the CaS content of inclusions in steel samples deformed at 1473 K was higher, while it was lower in the samples deformed at 1743 K. The CaO content changed inversely. Inclusions in steel samples deformed at 1473 K were a little harder than those in steel samples deformed at 1743 K due to the thicker CaS shell formed in the outer layer. The composition transformation of inclusions was mainly caused by the change of the thermodynamic equilibrium between the steel matrix and inclusions at various temperatures. In the solid steel at 1473 K, the strain concentrated on the soft calcium aluminate phase, resulting in a higher deformation amount of inclusions. In the semi‐solid steel at 1743 K, the soft steel matrix deformed more than inclusions, leading in turn to a smaller deformation of inclusions

Nitroxoline suppresses metastasis in bladder cancer via EGR1/circNDRG1/miR-520h/smad7/EMT signaling pathway

Bladder cancer is one of the most common and deadly cancer worldwide. Current chemotherapy has shown limited efficacy in improving outcomes for patients. Nitroxoline, an old and widely used oral antibiotic, which was known to treat for urinary tract infection for decades. Recent studies suggested that nitroxoline suppressed the tumor progression and metastasis, especially in bladder cancer. However, the underlying mechanism for anti-tumor activity of nitroxoline remains unclear. Methods: CircRNA microarray was used to explore the nitroxoline-mediated circRNA expression profile of bladder cancer lines. Transwell and wound-healing assay were applied to evaluate the capacity of metastasis. ChIP assay was chosen to prove the binding of promotor and transcription factor. RNA-pulldown assay was performed to explore the sponge of circRNA and microRNA. Results: We first identified the circNDRG1 (has_circ_0085656) as a novel candidate circRNA. Transwell and wound-healing assay demonstrated that circNDRG1 inhibited the metastasis of bladder cancer. ChIP assay showed that circNDRG1 was regulated by the transcription factor EGR1 by binding the promotor of host gene NDRG1. RNA-pulldown assay proved that circNDRG1 sponged miR-520h leading to the overexpression of smad7, which was a negative regulatory protein of EMT. Conclusions: Our research revealed that nitroxoline may suppress metastasis in bladder cancer via EGR1/circNDRG1/miR-520h/smad7/EMT signaling pathway

Residue behavior and dietary risk assessment of fluopyram in cowpea and determination in nine foodstuffs

Pesticide residues have been one of the food safety problems that plague consumers. It is necessary to develop validated detection methods to monitor pesticide residues in food. In this study, fluopyram was analyzed in fruits (banana, grape, and citrus) and vegetables (tomato, cucumber, cowpea, pepper, eggplant, and potato) by optimizing the QuEChERS in combination with GC-MS/MS. The recoveries of fluopyram in all food matrices ranged from 87.02% to 101.42% with RSD below 9.25%. The matrix effect of fluopyram ranging from −1.41% to 17.67%. Finally, this market investigation resulted in a total of 19 positive samples out of 128 market samples, all of which fell below the MRL with the exception of one tomato sample, which was above the EU MRL. Field trial of fluopyram on cowpea was conducted, the half-lives of fluopyram was 3.03–3.95 days, terminal residues ranged from .031–.596 mg/kg. Dietary risk assessment was performed on cowpea. The result indicates that the dietary risk of fluopyram in cowpeas is acceptable. The method of detection developed in this study could enable better monitoring of fluopyram residues in foodstuffs