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We analyze the evolution of transverse acceleration two-dimensional (2D) Airy beams propagating in Lieb photonic lattices with different photorefractive self-focusing nonlinearity. Numerical simulation shows that a decreased transverse acceleration of Airy beam and even a completely stopped state, the energy localized at the main lobe position, can be reached while the Airy beam is launched into the on-site/off-site of the Lieb photonic lattices by varying the medium nonlinearity. We discover that the transverse acceleration when the main lobe of Airy beam incident to off-site of the Lieb photonic lattice can be suppressed, which need a bias voltage larger than the on-site case when the main lobe of Airy beam incident to off-site of the Lieb photonic lattice. Additionally, the main lobe energy of the Airy beam still converges at the attractive defect lattice sites and spreads out to surrounding lattice sites due to the existence of repulsive defects under saturable nonlinearity.

A capillary electrophoresis coupled with electrochemiluminescent detection system (CE-ECL) was developed for the detection of polymerase chain reaction (PCR) amplicons. The ECL luminophore, tris(1,10-phenanthroline) ruthenium(II) (Ru(phen)(3)(2+)), was labeled to the PCR primers before amplification. Ru(phen)(3)(2+) was then introduced to PCR amplicons by PCR amplification. Eventually, the PCR amplicons were separated and detected by the homemade CE-ECL system. The detection of a typical genetically modified organism (GMO), Roundup Ready Soy (RRS), was shown as an example to demonstrate the reliability of the proposed approach. Four pairs of primers were amplified by multiple PCR (MPCR) simultaneously, three of which were targeted on the specific sequence of exogenous genes of RRS, and another was targeted on the endogenous reference gene of soybean. Both the conditions for PCR amplification and CE-ECL separation and detection were investigated in detail. Results showed that, under the optimal conditions, the proposed method can accurately identifying RRS. The corresponding limit of detection (LOD) was below 0.01% with 35 PCR cycles.

A liquid level sensor based on single leaky mode attenuation in a single-mode-multimode-single-mode (SMS) fiber structure is proposed and demonstrated, which aims at the liquid whose refractive index is higher than that of the silica fiber. Its operating principle is investigated theoretically by using the mode expansion method, and a monotonic and linear sensing response is obtained. Experiments are then carried out to verify the theoretical analysis.

The accurate node location is necessary for wireless sensor network applications in both the military and civilian areas. In this paper, we use the Cramer-Rao Bound (CRB) to verify that node localization algorithms based on received signal strength (RSS) and time of arrival (TOA) are both reasonable. The varying number of blindfolded nodes as well as the hybrid of RSS and TOA ranging methods are used to investigate the localization effect. Meanwhile, the maximum likelihood estimation (MLE) is applied to estimate the location accuracy. Simulation results demonstrate that both the localization algorithms based on RSS and TOA are absolutely effective, and the localization are much more accurate with either increasing blindfolded nodes or decreasing the certain parameters value. The node localization based on hybrid RSS/TOA ranging method results in 0.846m average RMS error and 0.229m average RMS CRB, which illustrates that it is much more accurate than the node locating based on RSS and TOA individually.

A simple temperature sensor based on a bent singlemode–multimode–singlemode (SMS) fiber structure fastened on a polymer base plate is proposed and experimentally investigated. The surrounding refractive index (RI) is higher than that of the silica fiber and RI changes with temperature will not lead to wavelength shift. This SMS fiber structure utilizes changing of temperature to control the curvature of SMS fiber which is induced by expanding of polymer base plate. The shifts of central wavelength are measured at temperature range from 59 to 82 °C. The proposed temperature sensor offers sensitivity of 3.9 nm/°C, which is significantly higher than that of a normal straight SMS structure or a grating-based fiber structure.

In this article, a CE with a new electrochemiluminescent (ECL) detection system was developed. A microfluidic ECL detection cell with less than 0.5 microL dead volumes was developed and used as detector for this system. A hydrofluoric acid-etched porous joint was made at 8 mm from the outlet of the separation capillary to isolate the CE high voltage from ECL detection. The proposed CE-ECL system was applied for separation and detection of some proteins labeled with tris(1,10-phenanthroline) ruthenium(II). High efficiency ECL-enhanced reagent, tripropylamine, was infused to the detection cell as coreactant by a micro-infusion system to obtain maximum and stable ECL signal. The performance of this setup was illustrated by the analysis of tris(1,10-phenanthroline) ruthenium(II)-labeled proteins. The background electrolyte for protein detection was 20 mM Tris-CH3COOH with 2.0% m/m PVP at pH 4.0. Under the optimal conditions, the corresponding LOD were 2.2 x 10(-10) M for HSA, 4.4 x 10(-10) M for casein (alpha-S1) and 5.1 x 10(-10) M for cytochrome c. The proposed method was also successfully used for the trace analysis of albumin in human urine without any pretreatment.

We propose a novel iteration-free blind phase noise estimation scheme for coherent optical orthogonal frequency division multiplexing (CO-OFDM) systems. In the new algorithm, the cost function is selected as the similar expression with real and imaginary parts as that in the modified constant modulus algorithm, and the new cost function is derived under some assumptions, where it is infinitely approximated by the sine and cosine functions. By means of the analytical formula of the cost function, the initial coarse common phase error can be obtained with only some samples, where the algorithm avoids computational complexity of conventional blind phase noise compensation scheme. In CO-OFDM systems with high-order modulation format (32 quadrature amplitude modulation) and narrow linewidth lasers, it is proved by the simulation results that the phase noise can be effectively compensated with the proposed blind estimation method.