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141.
Metallurgist - A model has been developed for predicting the metal temperature in the specified superheat range above the liquidus temperature inside the tundish of a continuous casting machine... 相似文献
142.
Broad Spectrum Anti-Bacterial Activity and Non-Selective Toxicity of Gum Arabic Silver Nanoparticles
Adewale O. Fadaka Samantha Meyer Omnia Ahmed Greta Geerts Madimabe A. Madiehe Mervin Meyer Nicole R. S. Sibuyi 《International journal of molecular sciences》2022,23(3)
Silver nanoparticles (AgNPs) are the most commercialized nanomaterials and presumed to be biocompatible based on the biological effects of the bulk material. However, their physico-chemical properties differ significantly to the bulk materials and are associated with unique biological properties. The study investigated the antimicrobial and cytotoxicity effects of AgNPs synthesized using gum arabic (GA), sodium borohydride (NaBH4), and their combination as reducing agents. The AgNPs were characterized using ultraviolet-visible spectrophotometry (UV-Vis), dynamic light scattering (DLS), transmission electron microscopy (TEM), and Fourier-transform infrared spectroscopy (FT-IR). The anti-bacterial activity was assessed using agar well diffusion and microdilution assays, and the cytotoxicity effects on Caco-2, HT-29 and KMST-6 cells using MTT assay. The GA-synthesized AgNPs (GA-AgNPs) demonstrated higher bactericidal activity against all bacteria, and non-selective cytotoxicity towards normal and cancer cells. AgNPs reduced by NaBH4 (C-AgNPs) and the combination of GA and NaBH4 (GAC-AgNPs) had insignificant anti-bacterial activity and cytotoxicity at ≥50 µg/mL. The study showed that despite the notion that AgNPs are safe and biocompatible, their toxicity cannot be overruled and that their toxicity can be channeled by using biocompatible polymers, thereby providing a therapeutic window at concentrations that are least harmful to mammalian cells but toxic to bacteria. 相似文献
143.
Jaakko Saari Fatima Siddique Sanna Korpela Elina Mntyl Teemu O. Ihalainen Katri Kaukinen Katriina Aalto-Setl Katri Lindfors Kati Juuti-Uusitalo 《International journal of molecular sciences》2022,23(3)
The small intestinal epithelium has an important role in nutrition, but also in drug absorption and metabolism. There are a few two-dimensional (2D) patient-derived induced pluripotent stem cell (iPSC)-based intestinal models enabling easy evaluation of transcellular transport. It is known that animal-derived components induce variation in the experimental outcomes. Therefore, we aimed to refine the differentiation protocol by using animal-free components. More specifically, we compared maturation of 2D-cultured iPCSs toward small intestinal epithelial cells when cultured either with or without serum, and either on Geltrex or on animal-free, recombinant laminin-based substrata. Differentiation status was characterized by qPCR, immunofluorescence imaging, and functionality assays. Our data suggest that differentiation toward definitive endoderm is more efficient without serum. Both collagen- and recombinant laminin-based coating supported differentiation of definitive endoderm, posterior definitive endoderm, and small intestinal epithelial cells from iPS-cells equally well. Small intestinal epithelial cells differentiated on recombinant laminin exhibited slightly more enterocyte specific cellular functionality than cells differentiated on Geltrex. Our data suggest that functional small intestinal epithelial cells can be generated from iPSCs in serum-free method on xeno-free substrata. This method is easily converted to an entirely xeno-free method. 相似文献
144.
Kanunnikova O. M. Aksenova V. V. Pushkarev B. E. Ladyanov V. I. 《Russian Journal of Non-Ferrous Metals》2019,60(4):390-400
Russian Journal of Non-Ferrous Metals - The influence of domestic nitrogen-containing corrosion inhibitors of the VNKh-L type on corrosion regularities of a zinc coating on steel in neutral media... 相似文献
145.
Roik T. A. Gavrysh O. A. Vitsiuk Yu. Yu. 《Powder Metallurgy and Metal Ceramics》2019,57(9-10):526-532
Powder Metallurgy and Metal Ceramics - The paper analyzes how the antifriction composites produced from AK12MMgN silumin grinding waste with MoS2 solid lubricant additions acquire their structure... 相似文献
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M. F. Bondarenko V. M. Kolychev O. N. Rudneva 《Chemistry and Technology of Fuels and Oils》1967,3(8):568-570
Conclusions It has been shown that nitromethane can be used successfully for separating kerosene-gas oil fractions to obtain raffinates which satisfy the requirements for diesel fuel plus highly aromatized extracts which contain less than 6% of saturated hydrocarbons.Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 8, pp. 27–29, August, 1967. 相似文献