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81.
Wireless Personal Communications - The recent evolution in wireless technologies has brought a new notion called Internet of Things (IoT), in which all objects can communicate to each other....  相似文献   
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A methodology was developed for the determination of molecular weight aveages of polyamic acid ionic salt (PAS) by size-exclusion chromatography (SEC). Polystyrene standards were used for calibration and THF-DMF 1:1 by volume containing 0.06 M LiBr and 0.06 M H3PO4 was used as the mobile phase. The proposed methodology was found to be reproducible.  相似文献   
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Wireless Networks - The entire world relates to some network capabilities in some way or the other. The data transmission on the network is getting more straightforward and quicker. An intrusion...  相似文献   
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Metal-dielectric composite nanospheres can amplify the scattering, emission, and absorption signature of molecules in their vicinity. Their ability to redistribute electromagnetic fields and produce pockets of greatly amplified fields is the dominant cause in achieving enhancement effects, for example, for surface-enhanced Raman spectroscopy. Extensive use of the field amplification has been made in devising ultrasensitive tag (label)?Cbased spectroscopic techniques. For example, we have recently proposed nano-layered alternating metal-dielectric particles (nano-LAMP)??a symmetric implementation of which is a nanoparticle consisting of alternating metal and dielectric shells. Exceptional spatial and spectral control on amplification can be achieved by designing the size and location of metal and dielectric layers in this geometry. Theoretical understanding exists and an engineering optimization approach can be adapted to design a palette of probes exploiting this control and tunability. However, current fabrication techniques are limited in their ability to achieve the required specificity in the spherical configurations. Hence, we investigate here the effects of variability, introduced by fabrication approaches into the structure of nano-LAMPs, on their spectroscopic signature. In particular, theoretical results are presented for the effects on enhancement due to variability in size, shape, and dielectric environment in the cases of gold?Csilica, silver?Csilica, and copper?Csilica nano-LAMPs. The results obtained show that the shape and dielectric properties of the metal shell play a crucial role in experimentally realizing the specificity of the magnitude of the enhancement and determine the key parameters to control and test in experimental validations.  相似文献   
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Photonic Network Communications - A full-duplex optical fiber/wireless single-channel coherent communication system is presented for high-speed data center interconnections. In-phase and quadrature...  相似文献   
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Wireless Personal Communications - Device-to-device (D2D) communication enables direct communication among users in close proximity, bypassing the core network. With relay assistance, D2D users can...  相似文献   
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Commercially available anhydrous zinc chloride has been found to be a highly efficient catalyst for dimethyl acetalization in high yields by treatment of aldehydes and ketones with trimethyl orthoformate in methanol-cyclohexane at reflux temperature.  相似文献   
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