Conventional superconductor could be explained by BCS theory (for Tc<35K), but the BCS theory is not valid for all superconductors with theincrease of critical temperature (Tc) in the continuous discovery of new superconductors. Later on, other theories, such as d-wave, line nodes, the point nodes, the s +g wave, the two gap model, have been proposed. After successfully applying the two-gap model on MgB2, we try to measure the magnetic field dependence of low-temperature specific heat on 2H-NbSe2. Subsequently, analysis is focused on checking whether the two-gap model could also be applied to NbSe2 . Based on this model, the corresponding two gap values are obtained. The nonlinear field dependence of electronic specific heat coefficient is also observed. Moreover, the positive curvature in Hc2(T) is similar to that in the other two-gap superconductor MgB2. Thus, the two-gap model appears to describe the superconducting gap function of 2H-NbSe2 better than s-wave and line nodes models.

In tilapia , sex determination is controled by genetic and triggered by the environmental factors. Expressed sequence tags ( EST ) derived from the developing tilapia brain is cloned in our lab. The cDNA full length of the gene, F10A83 was cloned. In the present study, F10A83 is a gene with 1526 bp of cDNA sequence, and deduced 176 amino acids of protein sequence. F10A83 was overexpressed as a GFP fusion protein in mouse neuroblastoma Neuro-2a cells. F10A83 is abundantly distributed in the nucleus of Neuro-2a cell. The protein of F10A83 was expressed in the prokaryotic cell (BL21) and eukaryotic cell (neuro-2a), and purified using a simple purification process, inducing, isolation, and Ni-NTA affinity chromatography. The protein of F10A83 in both E. coli system and neuro-2a cell line expression has been established.

The austenite stainless in high energy welding and tradition welding (TIG) produce different texture revolution and mechanicl property are main research. From EBSD analysis,austenite stainless in EBW,make more random texture to TIG welding,and main texture in TIG welding are cubic texture {100}<001> and copper texture {110}<1-1 2>.From EBW,there are some different texture in up fusion zone and down fusion zone .Experience of impact and hardness ,which find out copper and brass texture have more mechanical property for low-temperature, £_ ferrite content in center welding fusion and boundary fusion zone have different percent, then that can explain how differnt hardness value in center and fusion boundary about mechanical property.

The recent pollution norms have brought a strong emphasis on the reduction of diesel engine emissions. Low temperature combustion technology such as premixed compression ignition (PCI) has the capability to significantly and simultaneously reduce nitric oxides (NOx) and particulate matter (PM), thus meeting these specific pollution norms. There has been, however, observed loss in fuel conversion efficiency in some cases. This study analyzes how energy transfer and brake fuel conversion efficiency alter with (or are affected by) injection timings and exhaust gas recirculation (EGR) rate. The study is conducted for PCI combustion for four injection timings of 9°, 12°, 15° and 18° before top dead center (BTDC) and for four exhaust gas recirculation (EGR) rates of 39%, 40%, 41% and 42%. The data is collected from the experimental apparatus located in General Motors Collaborative Research Laboratory at the University of Michigan. The heat release is calculated to obtain various in-cylinder energy transfers. The brake fuel conversion efficiency decreases with an increase in EGR. The decrease in the brake fuel conversion efficiency is due to the decrease in work output. This decrease is due to an increase in the pumping work and an increase in friction and decrease in gross indicated work. The decrease in the combustion efficiency is because of the increased formation of unburnt products due to increased ignition delay caused by the application of EGR and decreasing air-fuel (A/F) ratio. A definite trend is not obtained for the contribution of heat transfer to the total energy distribution. However the total heat transfer decreases with retardation of injection timing because of decreasing combustion temperature. As the injection timing is retarded, the brake fuel conversion efficiency is found to decrease. This decrease is because of a decrease in net work output. This is because the time available for utilization of the energy released is less because of late combustion. The total heat transfer decreases with retardation of injection timing because of decreasing combustion temperature. The contribution of heat transfer to the total energy distribution decreases with increase in EGR.

This thesis proposes methodology to design a balun with imaginary impedance. Under given specification, including center frequency, size, output impedance, our methodology can be used to evaluate its feasibility of implementation using high-DK LTCC(Low Temperature Cofired Ceramic) process. We then extend the design to incorporate a filter, which can simplify the circuit to reduce the required components. An example of our design operating at 2.4 GHz is implemented. Its size is 1600¡Ñ800¡Ñ650 um3, showing significant miniature. The simulation and measurement results are shown to verify the effectiveness of our design.

Thesis (M.S.)--West Virginia University, 2009. / Title from document title page. Document formatted into pages; contains x, 112 p. : ill. (some col.). Document provides links to supplementary files in Pro/E, AI0WIN, Step, and Excel. Includes abstract. Includes bibliographical references (p. 110-112).

This study investigates the status and potential of the low temperature district heating system in Lyckebo, focusing on the distribution losses in the culvert system and in the heat exchangers. The Lyckebo system was built in the 1980’s as a test system with heating from a solar field and an electrical boiler. The unique features with this system were a cavern for storage of excess heat combined with a low temperature system. Today, the solar field has been substituted with two pellet boilers, but the cavern is still in service. Low temperature district heating systems are built in order to lower the losses, due to a smaller temperature difference between the medium in the culvert and the soil. This technology is used in newly built energy efficient residential areas, which makes it interesting to investigate the status of a system that was built in the 1980’s, in comparison to the possibilities of low temperature systems today. A simulation model has been developed to calculate the theoretical losses in the culvert system with production data from 2013. The total instantaneous losses in the culvert system were between 210- 280 kW and the highest losses in  can be found in the secondary system. There are heat exchangers in the system that has a return temperature of approximately 8°C lower than the return temperature in the system, which leads to the conclusion that many of the exchangers in the system probably have poor energy utilization.

In this work we proposed and demonstrated a novel and very cost effective method to fabricate bifacial solar cells with conventional structure. Bifacial cells collect sunlight from both faces, and hence have an obvious advantage over monofacial cells by occupying the same physical area and converting solar energy to electricity more efficiently. Despite this fact, bifacial cells are not that popular simply because of the costs associated with them. These costs are related to both manufacturing of the actual cells and integration of modules/solar panels. The cost of manufacturing is higher than regular commodity cells because the number of processing steps for fabrication is higher than their monofacial counterparts. The main reasons for that is a necessity of some kind of lithography step and/or alignment to make the grid pattern on both sides separately. Also metallization has to be done on both sides separately, one at a time. The method proposed in this work gets rid of both of those limitations by use of a lithography/alignment-less method for patterning contact holes, and a low temperature metallization scheme used for both the front and rear surfaces to grow metal simultaneously. This technique is simple and cost effective enough to be potentially incorporated in a batch process in industry, thereby reducing the cost of manufacturing. In this thesis we have presented preliminary results from the cells (bifacial and monofacial) fabricated using the above technique with proposals for further improvements. The measurement data underscores the clear advantage in using bifacial cells over monofacial cells fabricated using this method, in terms of efficiency. This also demonstrates that this proposed method is a viable way to manufacture bifacial cells with lower cost and relative ease. We also fabricated and measured monofacial solar cells in order to study the beneficial effects of including buried contacts as a possible part of device structure. The study shows significant improvement in efficiency due to incorporation of deep trenches for metal contacts in device design. / text

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