Study of Magnetic Abrasive Finishing for AISI321 Stainless Steel

In recent years, magnetic abrasive finishing (MAF) has become a reliable unconventional technology among researchers in industries due to need for the surface roughness reduction in metals. In this study, experiments based on influential parameters in the MAF process including rotational speed, working gap, and abrasive particle size were designed and conducted in the full factorial method in order to achieve the optimum parameters in finishing of steel AISI 321. A combination of silicon carbide (SiC), iron (Fe), and oil (SAE40) was utilized as magnetic abrasive tool. Prior to the experiments, the surface of the workpiece was abraded to the lowest value of roughness in order to obtain accurate results through the procedure. In general, the results indicate that the parameters of working gap, rotational speed, and abrasive particle size influence the surface roughness from the most to the least, respectively. Indeed, the minimum surface roughness is obtained through working gap of 1 mm, workpiece rotational speed of 500 rpm, and abrasive particle size of 100 mesh, with 50% improvement compared with initial surface roughness. Finally, the more involved parameters deviate from optimum values, the worse results are obtained compared with optimum acquired consequences.     

Continuous Flow Deformability‐Based Separation of Circulating Tumor Cells Using Microfluidic Ratchets

Circulating tumor cells (CTCs) offer tremendous potential for the detection and characterization of cancer. A key challenge for their isolation and subsequent analysis is the extreme rarity of these cells in circulation. Here, a novel label‐free method is described to enrich viable CTCs directly from whole blood based on their distinct deformability relative to hematological cells. This mechanism leverages the deformation of single cells through tapered micrometer scale constrictions using oscillatory flow in order to generate a ratcheting effect that produces distinct flow paths for CTCs, leukocytes, and erythrocytes. A label‐free separation of circulating tumor cells from whole blood is demonstrated, where target cells can be separated from background cells based on deformability despite their nearly identical size. In doping experiments, this microfluidic device is able to capture >90% of cancer cells from unprocessed whole blood to achieve 10⁴‐fold enrichment of target cells relative to leukocytes. In patients with metastatic castration‐resistant prostate cancer, where CTCs are not significantly larger than leukocytes, CTCs can be captured based on deformability at 25× greater yield than with the conventional CellSearch system. Finally, the CTCs separated using this approach are collected in suspension and are available for downstream molecular characterization.     

An evolutionary game approach to IoT task offloading in fog-cloud computing

The Journal of Supercomputing - Developing the edge and fog computing has been the result of the fast growth of cloud-based IoT applications. These new paradigms define new resource management...     

Encapsulation of flexible organic light emitting diodes by UV-cure epoxy siloxane

In this research, a silicon additive was synthesized by reaction of the hydroxyl terminated poly-dimethyl siloxane (PDMS-OH) with 3-glycidoxy propyl tri-methoxy silane (TMS-epoxy). The synthesized silicon additive characterized and evaluated to use as a curing agent for preparing high-performance and impermeable epoxy resin for encapsulation of flexible optoelectronic devices such as thin film photovoltaics and polymer light-emitting diodes to protect them against water penetration and increase their lifespan. The synthesized additive was characterized by FTIR, NMR, and elemental analysis. Thermal properties of the UV curable resin were investigated by using DSC and DMTA. The prepared UV cure epoxy resin exhibited an appropriate melting temperature (56.19 °C). Contact angle test, SEM, and calcium test was used to investigate the properties of UV-cured coating resin. The water contact angle of the cured prepared resin film showed good hydrophobicity. The SEM results confirmed the uniformity of cured film and UV cure resin dispersion. Transparency and flexibility of the cured film to encapsulate the flexible light emitting diodes are acceptable. The permeability of cured film to water vapor was evaluated by calcium test, which shows the cured film suitability to encapsulate the FOLED. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48033.     

单乙醇胺对水基钻井液体系中淀粉热稳定性的影响

为了提高水基钻井液体系中淀粉的热稳定性,在其中添加单乙醇胺,并对其效果进行了室内实验研究。研究表明,单乙醇胺的存在使钻井液的表观黏度、塑性黏度、动切力、静切力等提高,且显著降低了钻井液的滤失速率、减小了泥饼厚度。通过与淀粉聚合物建立氢键,单乙醇胺的存在可以避免高温下淀粉的水解,提高淀粉的热稳定性。淀粉作为天然聚合物可以提高钻井液流变性能、降低滤失量,但其发挥作用的最高温度仅为121℃,而单乙醇胺会使淀粉的耐温提高至160℃。单乙醇胺存在最佳浓度,高于最佳浓度时,其功效会下降。     

Corrosion and Erosion Analysis of AlCrN/CrN Multilayered Coating Applied by Cathodic Arc Physical Vapor Deposition (PVD)

Protection of Metals and Physical Chemistry of Surfaces - A multilayered AlCrN/CrN coating was applied on stainless steel C-450 precipitation hardened stainless steel by cathodic arc vapor...     

Improvement of light olefins production over the Co-Ni-Mn nano-catalyst: modeling and optimization of process by RSM

The co-precipitated Co-Ni-Mn nano-catalysts were evaluated for carbon monoxide hydrogenation. The influence of Al₂O₃, SiO₂, Zeolite, Active carbon, MgO supports and then the effect of best chosen support loading on the catalytic behavior and structure of ternary Co-Ni-Mn nano-catalysts were studied. The Co-Ni-Mn/20 wt%SiO₂ sample has shown highest selectivity toward light olefins production. Furthermore the influence of process conditions was investigated. Evaluation tests were performed under process conditions of P = 1–10 bar, T = 523-623 K, and H₂/CO = 0.67–3. The Response Surface Methodology (RSM) method was used for modeling and optimization process and the best conditions for catalyst evaluation were determined (T = 598.16 K, P = 1 atm and H₂/CO = 2.19). Under these conditions the highest selectivity of light olefins, higher CO conversion % and lower selectivity toward methane were achieved. Catalysts characteristics were investigated using XRD, BET, TEM, TGA, DSC, SEM, XPS, and TPR techniques. © 2021 Society of Chemical Industry (SCI).     

Zinc-based metal-organic frameworks: synthesis and recent progress in biomedical application

Journal of Inorganic and Organometallic Polymers and Materials - This review based on Zn-based MOF is summarized on new insights for targeted drug delivery of medicinal compounds and developed for...     

Comparative prioritization of sub-watersheds based on Flood Generation potential using physical,hydrological and co-managerial approaches

Water Resources Management - One of the important tools for watershed management and optimal decision making is the prioritization of sub-watersheds which can be effective in soil and water...     

Effect of Using CuO–Oil Nanofluid on Surface Roughness and Thermal Performance during Superfinishing Process

This research aims to investigate the effect of adding copper oxide nanoparticles to the oil Gr-6004 base fluid and its concentration changes from 0.1% to 0.4% on the surface roughness of gudgeon pin and the thermal conductivity of the nanofluids during the superfinishing process. The main novelty of this investigation is analyzing the impact of utilizing CuO/oil Gr-6004 nanofluid on thermal conductivity of oil and surface quality of gudgeon pin during superfinishing process. Based on the results, adding nanoparticles to the oil Gr-6004 has significantly reduced the surface roughness. In addition, by increasing the concentration of nanoparticles to 0.4%, the surface roughness has decreased by 57% compared to oil Gr-6004. Also, by adding nanoparticles, the thermal conductivity of the nanofluids has increased to 19.5%. In addition, dispersing CuO nanoparticles into base fluid reduces oil temperature by 17.44%.