A transparent polymer based solar cell was designed and fabricated to utilize the solar energy when exposed to sunlight. The transparent solar cell for window module was composed of a polymeric material PPV (Polypheny...A transparent polymer based solar cell was designed and fabricated to utilize the solar energy when exposed to sunlight. The transparent solar cell for window module was composed of a polymeric material PPV (Polyphenylene vinylene), ITO (Indium Tin Oxide) and electrode (Al, Mg, Ca). The polymeric sheet of this cell is by casting process, and electrode is applied on it by CVD (Chemical Vapor Deposition) process. The solar energy collected by this window can be used to power up small household electrical appliances. Recently, polymeric solar cell is made by a roll-to-roll process without using indium-tin oxide (ITO). A commercially available kapton (Polyimide) foil with an over layer of copper was used as the substrate. Sputtering of titanium metal on to the kapton/copper in a vacuum metalizing process gave the monolithic substrate and back electrode for the devices. The active layer was slot-die coated on to the kapton/Cu/Ti foil followed by slot-die coating of a layer of PET, PC or PEN.展开更多
Polyvinyl chloride (PVC) of different grades is the second most commonly used polymer for fabrication of electric cables and wires after polyethylene. Cables of domestic and industrial use of various capacities are fa...Polyvinyl chloride (PVC) of different grades is the second most commonly used polymer for fabrication of electric cables and wires after polyethylene. Cables of domestic and industrial use of various capacities are fabricated using different compounds of PVC. Mica is useful particulate filler extensively used to enhance the performance of many polymeric materials. It surface resistance and arc resistance improving its mechanical properties. In the present research work mica filled PVC composites of different concentrations were prepared using untreated and surface treated water ground mica of different particle size. Mica filled PVC composites were compounded for various compositions and test samples were prepared using compression moulding process. These samples were tested for electrical insulation and mechanical properties. The results shows enhancement in dielectric properties with improvement in Young’s modulus, stiffness, reduction in elongation at break and slight increase in shore D hardness of composites. Scanning electron microscopy was used to test the morphology of the samples which has shown proper distributions and adhesion of the filler mica in PVC matrix. There was some effect of surface treatment of mica on its mechanical and dielectric properties of the composite.展开更多
Air pollution is one of the leading cause of death for underdeveloped as well as developed countries. In 2011, the air pollution was the second leading cause of death in one of the main hospitals of the Kathmandu Vall...Air pollution is one of the leading cause of death for underdeveloped as well as developed countries. In 2011, the air pollution was the second leading cause of death in one of the main hospitals of the Kathmandu Valley, Nepal, and it was the third leading cause in the United States. Burning fossil fuels for transportation was one of the major causes. Among various impacts of the air pollution, COPD （chronic obstructive pulmonary disease） was one of the main consequences. In the 570 km2 Kathmandu Valley, vehicle registration was increased from 45,871 in 1990/1991 to 570,145 in 2010/2011, an increase of over 12-fold over 20 years. The vehicle registration and number of COPD patients＇ data were collected from various government divisions. In addition, the average daily travel distance and fuel mileage data were collected with a survey with residents of the Kathmandu Valley. This paper calculates the amount of carbon dioxide （CO2） emissions by transportation sector and determines correlation between CO2 emissions and COPD patients. Results show that there was a very high level of CO2 emissions, and it was positively correlated with the number of COPD patients in the valley.展开更多
文摘A transparent polymer based solar cell was designed and fabricated to utilize the solar energy when exposed to sunlight. The transparent solar cell for window module was composed of a polymeric material PPV (Polyphenylene vinylene), ITO (Indium Tin Oxide) and electrode (Al, Mg, Ca). The polymeric sheet of this cell is by casting process, and electrode is applied on it by CVD (Chemical Vapor Deposition) process. The solar energy collected by this window can be used to power up small household electrical appliances. Recently, polymeric solar cell is made by a roll-to-roll process without using indium-tin oxide (ITO). A commercially available kapton (Polyimide) foil with an over layer of copper was used as the substrate. Sputtering of titanium metal on to the kapton/copper in a vacuum metalizing process gave the monolithic substrate and back electrode for the devices. The active layer was slot-die coated on to the kapton/Cu/Ti foil followed by slot-die coating of a layer of PET, PC or PEN.
文摘Polyvinyl chloride (PVC) of different grades is the second most commonly used polymer for fabrication of electric cables and wires after polyethylene. Cables of domestic and industrial use of various capacities are fabricated using different compounds of PVC. Mica is useful particulate filler extensively used to enhance the performance of many polymeric materials. It surface resistance and arc resistance improving its mechanical properties. In the present research work mica filled PVC composites of different concentrations were prepared using untreated and surface treated water ground mica of different particle size. Mica filled PVC composites were compounded for various compositions and test samples were prepared using compression moulding process. These samples were tested for electrical insulation and mechanical properties. The results shows enhancement in dielectric properties with improvement in Young’s modulus, stiffness, reduction in elongation at break and slight increase in shore D hardness of composites. Scanning electron microscopy was used to test the morphology of the samples which has shown proper distributions and adhesion of the filler mica in PVC matrix. There was some effect of surface treatment of mica on its mechanical and dielectric properties of the composite.
文摘Air pollution is one of the leading cause of death for underdeveloped as well as developed countries. In 2011, the air pollution was the second leading cause of death in one of the main hospitals of the Kathmandu Valley, Nepal, and it was the third leading cause in the United States. Burning fossil fuels for transportation was one of the major causes. Among various impacts of the air pollution, COPD （chronic obstructive pulmonary disease） was one of the main consequences. In the 570 km2 Kathmandu Valley, vehicle registration was increased from 45,871 in 1990/1991 to 570,145 in 2010/2011, an increase of over 12-fold over 20 years. The vehicle registration and number of COPD patients＇ data were collected from various government divisions. In addition, the average daily travel distance and fuel mileage data were collected with a survey with residents of the Kathmandu Valley. This paper calculates the amount of carbon dioxide （CO2） emissions by transportation sector and determines correlation between CO2 emissions and COPD patients. Results show that there was a very high level of CO2 emissions, and it was positively correlated with the number of COPD patients in the valley.
