Most biological and synthetic receptors for small organic molecules employ a combination of relatively weak intermolecular interactions such as hydrogen bonds. A host compound that utilizes stronger yet reversible bonding in a synergistic manner could realize precise recognition, but the regulation and spatial arrangement of such reactive interaction moieties have been a challenge. Here, we show a multinuclear zinc complex synthesized from a macrocyclic ligand hexapap, which inwardly arranges labile metal coordination sites for external molecules. The metallomacrocycle forms a unique wavy-stacked structure upon binding a suitable length of dicarboxylic acids via multipoint coordination bonding. The saddle-shaped deformation and dimerization realize the differentiation of the interaction moieties, and change of guest-binding modes at specific metal coordination sites among the many present have been achieved utilizing acid/base as external stimuli.

No abstract

Radio over Fiber (RoF) and 10 Gbps optical On-Off Keying (OOK) signal can be simultaneously transmitted by using the stochastic process of optical OOK as a carrier for the radio frequency (RF) signal. However, the OOK modulation interferes with the RF signal. In this paper, an interference suppression scheme is proposed. The improvement in terms of error vector magnitude (EVM) is discussed from theoretical analysis and computer simulation. The proposed interference suppression scheme can be implemented using an analog electronic circuit containing a rectifier. The experiment shows that the proposal improves EVM.

Analog type radio over fiber (RoF) link transports radio frequency (RF) signal composed of different kind of frequency. Although previous papers have reported the transmitting multiple frequency signals using single wavelength without overlapping in electrical frequency domain, this paper assumes seriously contaminated channel for transmitting RF signal so that RF signal locates center frequency in main lobe of baseband (BB) signal. Specifically, this paper proposes RF signal transmission with 10 Gbps optical BB signal. Since RF signal is superimposed onto the optical BB signal, no additional light source is required. In addition, RF signal is naturally bandpass-sampled by random nonuniform sequence, therefore stochastic analysis is required. This paper derives error vector magnitude (EVM) of digitally modulated RF signal when the signal is simply regenerated by using bandpass filter. It is shown that theoretical analysis agrees with experimental results.

No abstract