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Adsorption of polyethyleneimine (PEI)−metal ion complexes onto the surfaces of carbon nanotubes (CNTs) and subsequent reduction of the metal ion leads to the fabrication of one-dimensional CNT/metal nanoparticle (CNT/M NP) heterogeneous nanostructures. Alternating adsorption of PEI−metal ion complexes and CNTs on substrates results in the formation of multilayered CNT films. After exposing the films to NaBH4, three-dimensional CNT composite films embedded with metal nanoparticles (NPs) are obtained. UV−visible spectroscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy are used to characterize the film assembly. The resulting (CNT/M NP)nfilms inherit the properties from both the metal NPs and CNTs that exhibit unique performance in surface-enhanced Raman scattering (SERS) and electrocatalytic activities to the reduction of O2; as a result, they are more attractive compared to (CNT/polyelectrolyte)nand (NP/polyelectrolyte)nfilms because of their multifunctionality. [ABSTRACT FROM AUTHOR]

In this paper, a derived physically expressive circuit model is presented for automatically deriving an equivalent-circuit model of a multilayered embedded RF passive. The scheme is based on the partial-element equivalent-circuit (PEEC) model and a simple circuit transformation. By defining an appropriate cutoff criterion that is related to the highest frequency of interest, most of the internal nodes in the coupling circuit generated by the PEEC model can be approximately absorbed by the remaining frequency-independent LC elements progressively. The model is very simple to implement and has apparent physical meaning. Mathematically, this model progressively recombines the least significant system pole with other less significant poles. The resultant physically expressive circuit model will be very useful in designing multi-layer embedded RF circuits. Four examples are given for demonstrating the validity and effectiveness of the scheme. [ABSTRACT FROM AUTHOR]

Spherical gold nanoparticles (3–5 nm) undergo a surprising fragmentation without extra energy imput and are converted into ultrasmall particles (less than 1.5 nm), which is a direct result of electron transfer between gold nanoparticles and cysteine. [ABSTRACT FROM AUTHOR]

Herein, we describe a simple and inexpensive method for forming superhydrophobic cloths with the highest water contact angle of close to 180°, in which normal commercial cloths serving as pristine materials are modified with suitable gold micro/nanostructures. [ABSTRACT FROM AUTHOR]

Photoluminescent properties of zero-dimensional LaPO4:Eu nanoparticles (NPs) and one-dimensional nanowires (NWs) prepared by the same wet-chemical synthesis technique were studied and compared. The results indicate that in NP Eu3+ occupied only one site, A, while in NW Eu3+ occupied the same site, A and an additional site B due to crystal anisotropy. Furthermore, the electronic transition rate of 5D1–∑J 7FJ in the NW increased from 14.9 to 28.9 ms-1 compared to the NP, while the nonradiative transition rate of 5D1–5D0 decreased from 24.1 to 19.7 ms-1. The luminescent quantum efficiency thus improved from 30% to 59%. This work demonstrates that a one-dimensional NW may be a more favorable device than a zero-dimensional NP for photoluminescence. [ABSTRACT FROM AUTHOR]

We present a quantum hyperdense coding protocol with hyperentanglement in polarization and spatial-mode degrees of freedom of photons first and then give the details for a quantum secure direct communication (QSDC) protocol based on this quantum hyperdense coding protocol. This QSDC protocol has the advantage of having a higher capacity than the quantum communication protocols with a qubit system. Compared with the QSDC protocol based on superdense coding with d-dimensional systems, this QSDC protocol is more feasible as the preparation of a high-dimension quantum system is more difficult than that of a two-level quantum system at present. [ABSTRACT FROM AUTHOR]

The article offers information about the mechanical penetration of beta-lactam–resistant (BLR) Gram-negative bacteria by programmable nanowires. It discusses the development of effective nanoantibiotics as limited by the poor understanding of changes in the physical nature of BLR Gram-negative bacteria.