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71.
α‐Amino nitriles are synthesized by the three‐component coupling reaction of aldehydes, amines and trimethylsilyl cyanide using FeCl3 as a solid acid catalyst, under solvent‐free conditions in good yields. The catalyst was recovered by simple filtration and was recycled in subsequent reactions. 相似文献
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Ioana Porosnicu Cristian M. Butnaru Ion Tiseanu Elena Stancu Cristian V. A. Munteanu Bogdan I. Bita Octavian G. Duliu Felix Sima 《Molecules (Basel, Switzerland)》2021,26(11)
The innovative strategy of using nanoparticles in radiotherapy has become an exciting topic due to the possibility of simultaneously improving local efficiency of radiation in tumors and real-time monitoring of the delivered doses. Yttrium oxide (Y2O3) nanoparticles (NPs) are used in material science to prepare phosphors for various applications including X-ray induced photodynamic therapy and in situ nano-dosimetry, but few available reports only addressed the effect induced in cells by combined exposure to different doses of superficial X-ray radiation and nanoparticles. Herein, we analyzed changes induced in melanoma cells by exposure to different doses of X-ray radiation and various concentrations of Y2O3 NPs. By evaluation of cell mitochondrial activity and production of intracellular reactive oxygen species (ROS), we estimated that 2, 4, and 6 Gy X-ray radiation doses are visibly altering the cells by inducing ROS production with increasing the dose while at 6 Gy the mitochondrial activity is also affected. Separately, high-concentrated solutions of 25, 50, and 100 µg/mL Y2O3 NPs were also found to affect the cells by inducing ROS production with the increase of concentration. Additionally, the colony-forming units assay evidenced a rather synergic effect of NPs and radiation. By adding the NPs to cells before irradiation, a decrease of the number of proliferating cell colonies was observed with increase of X-ray dose. DNA damage was evidenced by quantifying the γ-H2AX foci for cells treated with Y2O3 NPs and exposed to superficial X-ray radiation. Proteomic profile confirmed that a combined effect of 50 µg/mL Y2O3 NPs and 6 Gy X-ray dose induced mitochondria alterations and DNA changes in melanoma cells. 相似文献
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Yonghai Li Masoud Baghernejad Al‐Galiby Qusiy David ZsoltManrique Guanxin Zhang Joseph Hamill Yongchun Fu Peter Broekmann Wenjing Hong Thomas Wandlowski Deqing Zhang Colin Lambert 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(46):13790-13793
We studied charge transport through core‐substituted naphthalenediimide (NDI) single‐molecule junctions using the electrochemical STM‐based break‐junction technique in combination with DFT calculations. Conductance switching among three well‐defined states was demonstrated by electrochemically controlling the redox state of the pendent diimide unit of the molecule in an ionic liquid. The electrical conductances of the dianion and neutral states differ by more than one order of magnitude. The potential‐dependence of the charge‐transport characteristics of the NDI molecules was confirmed by DFT calculations, which account for electrochemical double‐layer effects on the conductance of the NDI junctions. This study suggests that integration of a pendant redox unit with strong coupling to a molecular backbone enables the tuning of charge transport through single‐molecule devices by controlling their redox states. 相似文献
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Research on Chemical Intermediates - In the present work, the degradation of hydroquinone in synthetic wastewater under sonocatalytic, photocatalytic, and sonophotocatalytic conditions was... 相似文献
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Adhesion characteristics of aromatic thermosetting copolyester and glass fiber laminates with copper foils for improved circuit boards
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Wenqing Wang Jacob Meyer Qingxuan Zeng Mingyu Li Bita Vaezian James Economy 《先进技术聚合物》2016,27(12):1577-1585
Copper foils are the vital elements used in microelectronic devices. Adequate adhesion between copper foils to various substrates, such as Si, SiO2 and polyimide, is crucial to functional electronic devices. Liquid‐crystalline polymers (LCPs) can be used as substrates for these modules as well as the adhesive to copper foils. The adhesion between aromatic thermosetting copolyester (ATSP)/fiberglass fabric (GF) laminates and copper foils was characterized by peel strength tests. It was found that ATSP/GF laminates with copper foil using ATSP oligomers as adhesive showed a highest average peel strength of 711 N · m?1. Scanning electron microscope (SEM) and Fourier Transform Infrared Spectroscopy (FTIR) showed an excellent bond between the composite and the copper foil interface. Failure occurred between the backside of the copper foil and the ATSP/GF laminates in the peeling test and the mechanism is discussed. Thermogravimetic analyzer (TGA) indicated a thermal stability up to 371°C for ATSP/GF composite substrate and a glass transition temperature of over 400°C as determined by peak in tan δ during Dynamic Mechanical Analysis (DMA). Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Processing of aromatic thermosetting copolyesters into foams and bulk parts: characterization and mechanical properties
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Fully dense sheets of aromatic thermosetting copolyester (ATSP) have been produced by blending ATSP oligomers, curing the blend to produce foam, grinding the cured material to a powder, followed by sintering of the cured powers via hot press. The resulting product possesses an excellent combination of mechanical strength and high‐temperature performance to help improve part functionality, gain long‐term reliability, and cost savings. Dynamic mechanical analysis of this system featured a glass transition higher than most available performance thermosets and thermoplastic polymers or reversible bonding polymer system described in literature. Compression and tensile properties of the foam and fully dense ATSP structures exceed those of most engineering polymers. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Peter A. Lieberzeit Abdul Rehman Naseer Iqbal Bita Najafi Franz L. Dickert 《Monatshefte für Chemie / Chemical Monthly》2009,391(8):947-952
Abstract An e-nose comprised of six sensing channels each coated with a molecularly imprinted polymer (MIP) selectively interacting
with alpha-pinene, thymol, estragol, linalool, and camphor, respectively, was designed. When applying it for continuous online
surveillance of terpenes emitted from basil and peppermint leaves as a criterion of freshness, it very appreciably reproduced
the emanation patterns from these plants as shown by GC-MS. Chromatography yielded a variety of terpenes in a concentration
range below 70 ppm. Trend lines obtained from the e-nose were corroborated by GC-MS and also appreciably fit the usual conduct
of these plants as observable by the human nose.
Graphical abstract
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