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Through the bending fatigue load test and static load test on concrete specimens in a chloride environment, we, in this research, studied the law of chloride ion diffusion in concretes under the coupled effect of bending fatigue load and chloride. The results showed that the concrete chloride ion diffusion coefficient was higher under bending fatigue load than that under static load at the same load level. When the load level was greater than 47%, the amplification was very obvious. Under the coupled effect of bending fatigue load and chloride, the service life of the concrete structure would be greatly shortened.

Deformation dilatometry has been used to simulate controlled hot rolling followed by controlled cooling of a Nb microalloyed pipeline steels, the microstructure and transformation characteristics in the steel and the effect of deformation on transformation are studied. According to the results of both dilatometry measurements and microstructure observations, the continuous cooling transformation curves (CCT) of the tested steels are constructed. The results show that Nb content and deformation enhance the formation of acicular ferrite; the microstructure of the steel range from PF, QF to AF with increasing of cooling rates from 0.5 to 50°C /s in a two stages controlled rolling and the microstructure revolution is sensitive to cooling rates when it is lower than 5°C /s, however, when the cooling rate increasing further, the microstructure didn’t change very much but M/A constituents in matrix is refined and dispersed.

Yttrium-doped lithium manganese oxide (LiMn0.98Y0.02O2) was prepared by ion exchange of lithium for sodium in NaMn0.98Y0.02O2 precursors obtained by using rheological phase reaction method. This material had small particle size, which was composed of grain size of about 100 nm. Especially, LiMn0.98Y0.02O2 delivered the initial discharge capacity of about 191 mA h g−1 at room temperature when cycled between 2.0 and 4.4 V vs Li/Li+. Moreover, it showed an excellent cycling behavior, its specific capacity remained above 173 mA h g−1 after 20 cycles, and the material did not transform into spinel structure during the electrochemical cycling according to the cyclic voltammograms and X-ray powder diffraction. The electrochemical results revealed that the doping of Y3+ improved the performance of LiMnO2 considerably.

In this paper, a thermodynamic constitutive model previously proposed by the authors was further developed in order to be applicable for the simulation of thermomechanical behavior of shape memory alloys under different loading conditions. The volume fractions of austenite and martensite variants were used as internal variables to describe the microstructural evolution. The model was used to investigate the behavior of a round tube Cu–Al–Zn–Mn polycrystalline shape memory alloy under various mechanical loads, including non-proportional loading, torsion cycling in opposite directions and the shape memory effect. The non-proportional loading simulation results were compared with experimental results reported in the literature.

The silicon photonic wire evanescent field (PWEF) sensor platform offers the advantages of small sensor size, high levels of function integration, and low cost manufacturing that comes with the use of established semiconductor fabrication processes. The technology should be fully compatible with existing infrastructure in molecular analysis and research and the manufactured sensor array chip cost should be low enough that the chips can be considered disposable. Furthermore, since many applications require simultaneous monitoring of many different simultaneous binding reactions, the possibility of integrating tens or even hundreds of independent molecular sensors on a single disposable sensor chip is very compelling. We present an overview of our multiplexed photonic wire sensor chip and a reader instrument that allows up to 128 independent binding reactions to be monitored simultaneously. A complete photonic wire molecular biosensor microarray chip architecture and supporting instrumentation is discussed. This microarray system is used to demonstrate a multiplexed assay for serotyping E. coli bacteria based on polyclonal antibody probe molecules. A coherent detection scheme that enables direct read-out of the optical phase and an order of magnitude enhancement of sensitivity compared to conventional detection is also discussed. Finally, we present advances in Fourier-transform interferometer arrays for spectroscopic sensing. A planar waveguide Fourier-transform spectrometer with densely arrayed Mach-Zehnder interferometers is presented. Subwavelength gratings are used to produce an optical path difference without waveguide bends. The fabricated device comprises of an array of 32 Mach-Zehnder interferometers, which produce a spatial interferogram without any moving parts, yielding a spectral resolution of 50 pm and a free-spectral range of 0.78 nm. As a result of similar propagation losses in subwavelength grating waveguides and conventional strip waveguides, loss imbalance is minimized and high interferometric extinction ratio of -25 to -30 dB is obtained. Furthermore, phase and amplitude errors arising from normal fabrication variation are compensated by the spectral retrieval process using calibration measurements., 2014 16th International Conference on Transparent Optical Networks (ICTON), 6-10 July 2014, Graz, Austria

We report a silicon-on-insulator ring resonator biosensor array with one output port, using wavelength division multiplexing as the addressing scheme. With the use of on-chip referencing for environmental drift cancellation, simultaneous monitoring of multiplexed molecular bindings is demonstrated, with a resolution of 0.3 pg/mm(2) (40 ag of total mass) for protein concentrations over 4 orders of magnitude down to 20 pM. Reactions are measured over time periods as long as 3 h with high stability.

Photonic wire evanescent field (PWEF) sensor chips have been developed for multiplexed label free molecular detection. The sensors are made using 260 nm ×450 nm cross-section silicon waveguides folded into spirals less than 200 μm in diameter, but with an overall sensor length of more than a millimeter. The long propagation length gives a response to molecular binding much better than currently available tools for label-free molecular sensing. These sensors can be arrayed at densities up to ten or more per square millimeter. This talk reviews our ongoing work on the photonic wire sensor chip design and layout, on-chip integrated fluidics, optical coupling, and chip interrogation using arrays of grating couplers formed using sub-wavelength patterned structures. The goal is to develop a commercially viable sensor platform by addressing cost-of-instrumentation, cost per measurement, ease-of-use, and by increasing the number of sensors that can be simultaneously monitored. © 2011 IEEE., 2011 ICO International Conference on Information Photonics, IP 2011, 18 May 2011 through 20 May 2011, Ottawa, ON

We are developing a photonic wire evanescent field (PWEF) sensor chip using 260 nm x 450 nm cross-section silicon photonic wire waveguides. The waveguide mode is strongly localized near the silicon surface, so that light interacts strongly with molecules bound to the waveguide surface. The millimeter long sensor waveguides can be folded into tight spiral structures less than 200 micrometers in diameter, which can be arrayed at densities up to ten or more independent sensors per square millimeter. The long propagation length in each sensor element gives a response to molecular binding much better than currently available tools for label-free molecular sensing. Cost of instrumentation, cost per measurement, ease-of-use, and the number of sensors that can be simultaneously monitored on a sensor array chip are equally important in determining whether an instrument is practical for the end user and hence commercially viable. The objective of our recent work on PWEF sensor array chips and the associated instrumentation is to address all of these issues. This conference paper reviews our ongoing work on the photonic wire sensor chip design and layout, on-chip integrated fluidics, optical coupling, and chip interrogation using arrays of grating couplers formed using sub-wavelength patterned structures. © 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE)., SPIE BiOS, January 22-23, 2011, San Francisco, CA, USA, Series: Proceedings of SPIE; no. 7888

Degradable bioelastomers are an important branch of degradable polymeric biomaterials, which mainly present four characters different from other polymeric biomaterials: stable crosslinked structures of three-dimensional networks similar to the natural collagen and elastin endowing elasticity with the natural extracellular matrix, certain flexibility and elasticity which can provide mechanical stimulation for tissue engineering constructs, appropriate mechanical properties especially matching with soft tissues and organs of bodies, and easily adjustable and designable biodegradation by controlling their crosslinking density. They can be prepared by varied synthesis methods such as polycondensition, ring-opening polymerization, thermally and photo initiated radical polymerization, which are chiefly applied in soft tissue engineering and controlled drug delivery. The biodegradation is a very important property of degradable bioelastomers, which is often discussed in the studies. The degradation rates of degradable bioelastomers are usually able to be tuned in a wide range by controlling their molecular structure, segment length and composition, molar ratio of monomers, reaction temperature, polymerization time, curing method and degradation condition, etc. In this chapter, degradable bioelastomers are classified as eight types of degradable segmented polyurethane bioelastomers, poly(e-caprolactone) related bioelastomers, polylactide related bioelastomers, polycarbonate related bioelastomers, poly(glycerol sebacate) bioelastomer and its derivatives, citric acid related polyester bioelastomers, poly(ether ester) bioelastomers and poly(ester amide) bioelastomers, and their synthesis and biodegradation are specially introduced accompanying with many typical examples. Moreover, other several novel degradable bioelastomers are also mentioned. In the future, degradable bioelastomers are sure to play a more important role in degradable polymeric biomaterials.

We report multiplexed label-free measurements of biomolecular interactions using silicon wire waveguide sensor arrays. The sensors are addressed using both wavelength division multiplexing and power broadcasting approaches. We demonstrate the real-time monitoring of antibody-antigen reactions using complementary and mismatched IgG receptor-analyte pairs and bovine serum albumin. The measured level of detection for each sensor element corresponds to a surface coverage of less than ~ 0.02% of a protein, OSA Integrated Photonics Research, Silicon and Nanophotonics (IPRSN), July 26-28, 2010, Monterey, USA

A complete photonic wire molecular biosensor microarray chip architecture and supporting instrumentation is described. Chip layouts with 16 and 128 independent sensors have been fabricated and tested, where each sensor can provide an independent molecular binding curve. Each sensor is 50 μm in diameter, and consists of a millimeter long silicon photonic wire waveguide folded into a spiral ring resonator. An array of 128 sensors occupies a 2 × 2 mm2 area on a 6 × 9 mm2 chip. Microfluidic sample delivery channels are fabricated monolithically on the chip. The size and layout of the sensor array is fully compatible with commercial spotting tools designed to independently functionalize fluorescence based biochips. The sensor chips are interrogated using an instrument that delivers sample fluid to the chip and is capable of acquiring up to 128 optical sensor outputs simultaneously and in real time. Coupling light from the sensor chip is accomplished through arrays of sub-wavelength surface grating couplers, and the signals are collected by a fixed two-dimensional detector array. The chip and instrument are designed so that connection of the fluid delivery system and optical alignment are automated, and can be completed in a few seconds with no active user input. This microarray system is used to demonstrate a multiplexed assay for serotyping E. coli bacteria using serospecific polyclonal antibody probe molecules. © 2013 Optical Society of America.

Useful properties of eutectic alloys have been found to relate to the presence of granulated discontinuous phase, and its formation is encouraged during solidification; although difficulties are encountered in some alloy systems. In the present paper it is suggested that discontinuous phase granulation can be achieved through either solidification processing or heat treatment. The kinetics of granulation during heat treatment and the factors affecting it have been analysed and examined for eutectic silicon in Al–Si alloys and for graphite in cast irons during heat treatment, using the techniques of high-temperature and quantitative metallography. The concept of combined control of the size and morphology of the discontinuous phase through solidification and heat treatment was developed.MST/254

Rolling contact fatigue (RCF) of rail can be a significant problem affecting safety and maintenance. Rail materials have been optimized to reduce it, but not enough is known about how friction management products applied to the rail affect crack growth. This study presents experimental results carried out to explore the influence of different lubricants and application orders on wear and pre-existing RCF cracks in rail materials. The results indicate that the types or properties of lubricants have a vital role in the wear rate and fatigue crack growth characteristics of rail materials after conditioning with 5000 dry cycles to initiate cracks. Using a different application order of two lubricants has a significant influence on the crack growth angles in the rail rollers.