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Hojat Veisi Ramin Ghorbani‐Vaghei Somayeh Akbari Dadamahaleh 《Journal of heterocyclic chemistry》2011,48(3):699-705
Poly(N‐bromobenzene‐1,3‐disulfonamide) and N,N,N′,N′‐tetrabromobenzene‐1,3‐disulfonamide are effective catalysts for chemoselective dithioacetalization of aldehydes in the presence of ketones under neutral conditions. J. Heterocyclic Chem., (2011). 相似文献
233.
Guido Mann Jens Vogel Rüdiger Preuß Pouya Vaziri Mohammadali Zoheidi Markus Eberstein Jörg Krüger 《Applied Physics A: Materials Science & Processing》2008,92(4):853-857
High-power optical multimode fibers are essential components for materials processing and surgery and can limit the performance
of expensive systems due to breakdown at the end faces. The aim of this paper is the determination of laser-induced damage
thresholds (LIDT) of fibers (FiberTech) and preforms (Heraeus Suprasil F300). Preforms served as models. They were heated
up to maximum temperatures of 1100, 1300 and 1500°C and cooled down to room temperature at rates of 10 K min−1 (oven) and ∼105 K min−1 (quenched in air) to freeze in various structural states simulating different conditions similar to a drawing process during
the production of fibers. Single- and multi-pulse LIDT measurements were done in accordance with the relevant ISO standards.
Nd:YAG laser pulses with durations of 15 ns (1064 nm wavelength) and 8.5 ns (532 nm) at a repetition rate of 10 Hz were used.
For the preforms, LIDT values (1-on-1) ranged from 220 to 350 J/cm2 (1064 nm) and from 80 to 110 J/cm2 (532 nm), respectively. A multi-pulse impact changed the thresholds to lower values. The LIDT (1064 nm wavelength) of the
preforms can be regarded as a lower limit for those of the fibers. 相似文献
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Mahmoud Gharbavi Behrooz Johari Roghayeh Ghorbani Hamid Madanchi Ali Sharafi 《应用有机金属化学》2023,37(1):e6926
Glioblastoma multiforme (GBM) is the most aggressive malignant tumor of the brain. It has different glutamate receptor types. So, these receptors can be a suitable target for GBM treatment. The current study investigated the anticancer effects of bovine serum albumin (BSA)-Baicalein @Zn-Glu nanostructure mediated-GluRs in human glioblastoma U87 cells. BSA-Ba@Zn-Glu hybrid nanoparticles (NPs) were set and considered transporters for Baicalein (Ba) active compound delivery. BSA-Ba@Zn-Glu NPs were synthesized by a single-step reduction process. The successful production was confirmed through transmission electron microscopy (TEM), dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FT-IR), and hemolysis test. The cytotoxic efficacy and apoptosis rate of the nanostructures on U87 glioblastoma cells were investigated by 3-(4,5-dimethylthialzol-a-yl)-2,5 diphenyltetrazolium bromide (MTT) and flow cytometry assays, respectively. The synthesized BSA-Ba@Zn-Glu nanostructures with a diameter of 142.40 ± 1.91 to 177.10 ± 1.87 nm and zeta potential of −10.57 ± 0.71 to −35.77 ± 0.60 mV are suitable for extravasation into tumor cells. The drug release from the BSA-Ba@Zn NPs showed controlled and pH-dependent behavior. In vitro results indicated that the BSA-Ba@Zn-Glu NPs significantly reduce cell viability and promote apoptosis of U87 cancer cells. It revealed the cytotoxic effect of the Baicalein and an increase in cellular uptake of nanoparticles by Glu receptors. Zn NPs were synthesized based on a green synthesis method. BSA NPs were used as a nano-platform for Glu conjugation and Ba drug delivery. BSA-Ba@Zn-Glu NPs induce cytotoxicity and apoptosis in human brain cancer cells (U87) in a dose-dependent manner. Finally, this nanostructure could be served in targeted drug delivery in vivo studies and applied along with other strategies such as X-ray irradiation as combinational therapies in future studies. 相似文献
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