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A sudden leak of phenylethylene is an urgent issue for the surrounding environment. To mitigate its negative effect, the decontamination efficiency of phenylethylene on an activated carbon (AC)-based adsorbent was investigated. Factors such as the particle size and the temperature, that could affect the adsorption ratio, were explored. Meanwhile, the efficiency of AC, pretreated with different KMnO4 and NaClO concentrations, was examined. It was proven that the decontamination efficiency was higher for the 300-mesh AC compared to the 200-mesh AC. The introduction of the oxidizer, KMnO4, had a negative effect on phenylethylene adsorption. Nevertheless, the NaClO-modified AC showed a positive influence on phenylethylene removal, while its decontamination gradually improved with the increase of the NaClO concentration. It was also found that the adsorption rate of phenylethylene was ascended with the temperature rise. After 1 h of adsorption with AC heated to 200°C, no phenylethylene desorption was observed.

A sudden leak of phenylamine is an urgent environmental issue due to its liquidity and volatility. To overcome this difficulty, the decontamination efficiency of spray, foam, and activated carbon to phenylamine was explored using simulated leak box. Furthermore, a new decontamination method of foam coupling with acidic spray was proposed to decontaminate phenylamine. Its decontamination efficiency for phenylamine gas was up to 90% after 3 min adsorption at 3:1 mass ratio and phenylamine liquid was solidified quickly.

To achieve automatic rolling of an unmanned vibratory roller, the path following control model of the vibratory roller was built and the influence of drum vibration is considered since the roller always works in the vibration condition. The vibration dynamic model was first established. The dynamic model of the vibratory roller under the influence of exciting force was then developed. The heading following control algorithm based on preview strategy was designed to control the path following errors in unmanned automatic rolling. The control performance of the algorithm was analyzed by simulation based on the vibration dynamic model and the dynamic and kinematic models of the vibratory roller. The control performance was also verified by the field automatic rolling experiments. Experimental results show that the maximum absolute lateral error of line path following is 24.5 cm in vibration rolling and 19.5 cm in non-vibration rolling at the traveling speed of 0.83 m/s. The average absolute lateral errors in vibration and non-vibration rolling are both less than 10 cm. The experimental results verify the effectiveness and achievability of the control algorithm for unmanned vibration rolling. Besides, the ratio of completely compacted area to the whole set area is 97.28% in the field automatic rolling experiment, which meets the requirements for practical use.

Nonreciprocity is a fundamental property of networks. Unlike electronic networks theory, optical network theory is still a field to be investigated. Lightwave systems, including fiber optic and integrated optic, are becoming more and more complex, new function blocks ( or components) and networking strategies are very important for future highly integrated lightwave circuits. Several common nonreciprocal optical effects studied in this disseration and several basic applications to fiber components and fiber optic metrology systems analyzed. The common optical nonreciprocal phenomena include the Faraday effect, Sagnac effect, Fresnel drag effect, nonlinearity or asymmetric geometric structure-induced nonreciprocity, and some pseudo nonreciprocity. The best-known application of nonreciprocity to optical components is the isolator, and the known nonreciprocity-based fiber optic sensors are the fiber optic gyroscope and the fiber optic current sensor. The major difficulty in forming a general optical network theory is the complexity of optical signals compared to the electrical signal, because each light signal consists of four independent parameters, all of which changing during transmission. Fortunately, most optical signals can be classified into intensity-based and phase-based systems, and the Jones matrix technique is the ideal tool for describing the intensity-based system. Several reciprocity-insensitive structures designed and analyzed in chapter 3. The performance of the intensity-based reciprocity-insensitive structure (IRIS) was employed successfully in a fiber optic current sensor for stabilizing the signal from birefringence influences in chapter 5. A variable-loop Sagnac interferometer was designed and applied to distributed sensing in chapter 6, and the reciprocity-insensitive property of the Sagnac interferometer was preserved. Polarization independent isolators and wavelength division multiplexers were also realized by employing suitable nonreciprocal effects and were discussed in chapter 2 and chapter 4, and their feasibilities were verified by experiment. The primary contributions of this dissertation are the study of common nonreciprocal optical effects and demonstration of several basic applications to fiber components and fiber metrology systems. Ph. D.

New sapphire fiber based sensor structures for high temperature strain measurement are proposed and studied in this report. The self-mixing interferometry has been studied and tested. The advantage of this technique is the source coherence insensitivity and direction distinguishment capability. Fringes of the self-mixing interferometer built with standard multimode fiber and sapphire fiber were observed. The application of this technique to static strain rneasureament seems difficult to stabilize, whereas its implementation to acoustic sensing with single-mode fiber coil as the sensing component will be very interesting. The approach by Moire interferometry and equal-path coherence matching interferometer are two promising methods for high temperature displacement measurement. The advantages of the Moire interferometer are source coherence independence and large measurement range. The advantage of coherence matching absolute interferometer is its simplicity in sensor structure. The structures of coherence matching methods and multiplexing techniques are generalized. From this research, we can conclude that the sapphire fiber based high temperature extensometer may be realized by different methods. Master of Science