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Research on the synthesis of organosulfur compounds is an attractive research fields among synthetic chemists. Diaryl sulfides and benzothiophenes are important organosulfur compounds with a diverse range of biological activities which are privileged in the structure of numerous biological molecules and natural products. In this paper, we successfully fabricated copper complex supported on the surface of magnetic nanoparticles modified with imine-thiazole ligand and studied its catalytic activity in the synthesis of diaryl sulfides and benzothiophenes. The structure of Fe3O4@SiO2-(Imine-Thiazole)-Cu(OAc)2 nanomaterial was well characterized by Fourier transform infrared, scanning electron microscope, energy-dispersive X-ray spectrum, transmission electron microscopy, thermal gravimetric analysis, vibrating sample magnetometer, X-ray powder diffraction (XRD), Atomic absorption spectroscopy (AAS) and Inductively coupled plasma-optical emission spectroscopy (ICP-OES) techniques. The Fe3O4@SiO2-(Imine-Thiazole)-Cu(OAc)2 catalyst could be recovered via magnetic attraction and (upon washing with an organic phase and water) could be reused at least seven runs without a noticeable decrease in its performance.

In order to study the effect of glaze erosion on the performance of porcelain post insulator, an inclined plane (IP) test similar to IEC 60587 standard was conducted on a cylindrical insulator sample under laboratory conditions for ac voltage, and a new test method, called graphite-layer-based glaze erosion test was proposed in this paper and performed on the sheds of a 40.5 kV post insulator. The experimental details of the graphite-layerbased glaze erosion test was introduced, the technical points of which are coating a graphite layer on the surface of the shed using a brush mold which contains multiple hollowed-out rhombic grids, and arranging high voltage electrode at shed root and grounded electrode at shed edge respectively at both ends of the graphite layer, so as to form continuous and stable surface arcing under ac voltage and therefore achieve desired glaze electrical erosion effect. The graphite layer is a uniform viscous mixture made up with flake graphite and liquid glue according to a quality ratio of 1:1.2. The arcing process, arc current characteristics, surface temperature, and glaze erosion appearance were analyzed. Leakage current under power frequency voltage and flashover voltage of the eroded cylindrical insulator by IP test were measured, while porosity test and scanning electron microscopy (SEM) tests were conducted on samples taken from the sheds after graphite-layer-based glaze erosion test. The results indicate that glaze erosion will decrease both electrical and mechanical performance of the porcelain post insulator. The new test method proposed in this paper has been proved to be effective for glaze erosion test and consumes much less time compared with IP test, which provides a new idea for accelerated tracking and erosion test of glaze and porcelain materials so as to study the aging characteristics of porcelain insulators.

Defects of high-voltage transmission lines are often accompanied with corona discharge; and corona discharge would produce ultraviolet. Based on this principle, the UV imager can be used in detecting the defect. Electric field strength is the main factor affecting the corona discharge, which is determined by power-supply and experimental model. In this paper, UV measurement of different defects was studied, and the effect of Applied-voltage on corona discharge of defects was acquired. A quadratic relationship exists between the UV strength produced by corona discharge and applied voltage. The quadratic coefficient A is between 0.31~0.37, which is increase with the length increasing at the experimental conditions in this paper.

Masteroppgave i informasjons- og kommunikasjonsteknologi 2009 – Universitetet i Agder, Grimstad Condition-Based Maintenance (CBM) system is getting quite popular in the industry and defense fields these days. A CBM system can efficiently predict the potential failures of the system and send the alarms. As a result, the lifetime of the system can be prolonged and the breakdown time can be decreased dramatically. The intelligent CBM system even can make the decision without any human intervention in the future. This master thesis concentrates on the diagnosis part and the visualization part of the CBM system for a fan. The diagnosis is the core part of a CBM, which requires an efficient and optimum method for the different situations in reality. This method directly impacts the performance of the CBM. The visualization is an interface by which the personnel and the software system exchange information. The quality of this interface also can impact the feeling of customers and its availability. In this master thesis, I developed a intelligent diagnosis solution for the CBM system for the fan. The system has the ability to learn from the experience and the known data, rather than just judges the values with the certain thresholds which is widely used as a tradition system state monitor method. I also implement the prototype. This master thesis deals with a partial solution of an efficient CBM system for the fan in reality. The diagnosis solution can predict the potential failure in advance. The graphic user interface is designed to be easily understandable and neat. The personnel can read all related information from the interface at the first place. However, there is still much work to do. The method in this thesis and its prototype implementation can give the readers an overview and knowledge of a CBM system.