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61.
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   
62.
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   
63.
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   
64.
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     相似文献   
65.
The heterogeneous nature of cells can be an issue for in vitro analysis of cell function due to cell type differences within a population. Observations are most often averaged and dependent on the homogeneity or lack thereof for most cell types. Patterning of features at the sub-cellular scale (< 10 μm) allows for single cell manipulation. Additionally, the ability to pattern multiple materials simultaneously with nanoscale precision enables facile fabrication of multiplexed cellular microenvironment arrays. Here we use this ability to deliver different materials to single or few cells within hundreds of microns of each other on the same substrate. Calcein AM, Calcein Red AM and quantum dots are delivered to live single or few cells. This allows for exposing limited cell numbers to many well defined conditions, thus opening the possibility of single cell based assays.  相似文献   
66.
Certain phenols and naphtols were nitrated regioselectively with NaNO2 in the presence of KHSO4 at 50 °C in high yields.  相似文献   
67.
A highly yielding and fast method for the synthesis of heterocyclic compounds with trialkyl orthoformate using molecular sieve 3Å as a catalyst is described.  相似文献   
68.
The one-pot synthesis of spirooxindoles via three-component reaction of urea, isatin, and 1,3-dicarbonyl compounds in the presence of a catalytic amount of p-toluenesulfonic acid in acetonitrile has been carried out.

Additional information

ACKNOWLEDGMENT

The authors are thankful to the Alzahra Research Council for the partial financial support.  相似文献   
69.
Potassium ferrate impregnated on montmorillonite is a mild,cheap,and non-toxic reagent for the iodination of phenols, including naphthol,aromatic amines,and heterocyclic substrates in fair to excellent yields by a simple isolation procedure.  相似文献   
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