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One goal of metabolic engineering and synthetic biology for cyanobacteria and microalgae is to engineer strains that can optimally produce biofuels and commodity chemicals. However, the current workflow is slow and labor intensive with respect to assembly of genetic parts and characterization of production yields because of the slow growth rates of these organisms. Here, we review recent progress in the microfluidic photobioreactors and identify opportunities and unmet needs in metabolic engineering and synthetic biology. Because of the unprecedented experimental resolution down to the single cell level, long-term real-time monitoring capability, and high throughput with low cost, microfluidic photobioreactor technology will be an indispensible tool to speed up the development process, advance fundamental knowledge, and realize the full potential of metabolic engineering and synthetic biology for cyanobacteria and microalgae.

This paper discusses the application of position-sensitive detector (PSD) technology to a real bridge for the purpose of health monitoring. The PSD system consists of two parts: the assembly of PSD targets with mounted LEDs for emitting light spots, and the PSD light-spot capturer for tracking the sensing lights. To verify the performance and reliability of the PSD system, a series of experiments were conducted on an actual bridge with both a dead load and a live load on the superstructure, and an impact load on the substructure. Multiple PSD targets were mounted on the bottom of the girder for the superstructure, and a reference target was mounted on the top of the pier cap, taken as a fixed point. A 400-kN truck was used as the dead load and as the live load, with various speeds. A single target was mounted on the side of the pier cap beam for the substructure, and a 0.6-kN log was used for the impact. A corresponding dynamic response analysis was performed based on a fine-tuned finite element model to provide a reference for the response of the structure. Comparison of the time history and the frequency domain analysis demonstrated that the measured data and analysis result fitted well with one another. The proposed PSD system has shown a high potential of applicability in the practice of bridge health monitoring. 1 8 January 436high-resolution displacement measurements are proposed in this study. This may be the best solution since other structural responses, such as velocity and acceleration, can be derived by simple differentiation without any bias. In addition, based on the displacement data, valuable information regarding components, such as vibration characteristics, fundamental frequency, and the attenuation coefficient of the bridge structure, can be obtained. Structural displacement sensors, such as linear variable differential transformers (LVDTs) and dial gauges, traditionally perform displacement measurements at a certain point on a structure. They are flexible for measuring displacement in all directions, and meet the resolution requirements for structural testing. However, these sensors require a stationary platform as a measurement reference to which the sensors are to be fastened. Such a platform must be close to the structure, because the sensor is small compared with the structure. In addition, these devices are hard wired and thus subjected to a possible loss of accuracy. This has been a typical problem for field-testing, in that gaining access to the structure is costly, and establishing a required platform is difficult.To solve this problem, various non-contact real-time displacement measurement technologies were developed over the last two decades. Stephen et al.[1] proposed a visual tracking system to measure the deck displacement of the Humber Bridge in the United Kingdom. During real-time processing, transputer-based parallel processing techniques were employed to track the motion of multiple, independent objects at a video frame rate. For object tracking, templates of userselected obj...

Thermal power generation is a complex production system, and electric operation is an important work. The generating capacity of Zhangjiakou power plant is 2400 thousand kW, ranking the third in our country. Its technology and equipment and the process are representative. In order to ensure the safety of the electrical operation, on the basis of analysis of accident cases for more than ten years, using the method of system analysis, this article summarizes the risk factors and control measures of electrical operation. With strict implementation, the electrical accidents of our planet will decrease year by year.

The metal-air batteries, especially the Zinc-air batteries, are great solutions to the growing energy crisis with excellent rechargeable capacity. ORR is the key electro-chemical reaction in Zinc-air batteries, and the development of the ORR efficiency is being studied extensively. The doping of transition metal in Co3O4, with the basement of N-doped graphene have been confirmed to have catalytic activity which can be comparable to Pt/C. Herein, the Fe-doped Co3O4 supported by N-doped graphene is constructed as the catalyst of ORR, and that without Fe doping is also constructed as comparison. Through first-principle calculation, it shows that the adsorption energies to O2 on the same site of each surface and on different sites on Fe-doped one. The partial density of state of the O2 adsorption system shows the effects of electron transfer and orbital hybridization on catalysis, which provide evidence to the catalytic mechanism with Fe doping. The energy changes of each step in ORR on catalyst with Fe doping and without Fe doping show the shortcomings of the simulation, including the spin of Fe atoms. Thus the study confirms that the adding of Fe contributes to the catalystic capability compared to the pure Co3O4.