Finite Element Analysis of Spur Gear Set

A Finite Element procedure has been developed in this work to determine the load distribution factor, Km, of the AGMA formula for a set of spur gear. At first, a spur gear with perfect involute is modeled using a 3-D CAD software. The model is them is assembled with shafts having 1, 2, and 3 degree misalignments. The generated 3-D models were in turn imported to ANSYS workbench to calculate the maximum bending and contact stresses using finite element method. The results generated were then compared with the maximum bending stress results obtained for parallel shafts to estimate the Load Distribution Factor Km. This study resulted in Km values of 1.03,1.11, and 1.1

Gas Composition Effects in a CI Engine Converted to SI Natural Gas Operation

Low-carbon fuels such as natural gas (NG) have the potential to lower the demand of petroleum-based fuels, reduce engine-out emissions, and increase IC engine thermal efficiency. One of the most rapid and efficient use of NG in the transportation sector would be as a direct replacement of the diesel fuel in compression ignition (CI) engines without any major engine modifications to the combustion chamber such as new pistons and/or engine head. An issue is the large variation in NG composition with the location and age of the gas well across U.S., which would affect engine operation, as well as the technology integration with emissions after treatment systems. This thesis describes the use a conventional CI engine modified for spark ignition (SI) NG operation to investigate the effects of methane and a C1-C4 alkane blend on main combustion parameters like in-cylinder pressure, apparent heat release rate, IMEP, etc. Steady-state engine experiments were conducted at several operating conditions that changed spark timing, engine speed, and equivalence ratio. The study found that C1-C4 alkane blend operation increased peak pressure, IMEP, and indicated thermal efficiency compared to methane, for all the operating conditions investigated in this work. This suggests caution when translating methane-based experimental observations to real world NG operation, even for NG with high methane percentage as the one used in this work. As many NG studies in the literature used methane as an NG surrogate, a better understanding of real fuel effects in diesel-like combustion environments could be important for the successful conversion of conventional diesel engines to NG operation

PCR detection assay for sex determination in papaya using SCAR marker

Papaya (Carica papaya L., 2n = 18), a polygamous angiosperm, is a major fruit crop in tropical and subtropical regions. It is trioecious with three sex forms: male, female, and hermaphrodite, where sex determination is controlled by the XY chromosome pair with two slightly different Y chromosomes i.e. Y for male and Yh for hermaphrodite. Sex type determination in papaya, which cannot be determined either by embryo shape or morphology at the juvenile developmental stage, is an essential pre-requisite for crop improvement processes as it helps in identification of fruitful plants. Hence, molecular profiling could be used as an alternative that provides a quick and reliable identifi cation of sex types in plantlets at initial stages only. In the present study we have validated the sex linked sequence characterized amplified region (SCAR) marker W11 using PCR detection assay among different cultivars of papaya i.e. dioecious with either female or male and gynodioecious with either female or hermaphrodites and also performed a double-blind test for validating the seedlings of 84 F1 plants, which resulted in their sex determination. The assay clearly gives 800 bp band in male plants in dioecious types and hermaphrodite in gynodioecious plants

The effects of composts on soil physical properties and crop growth

reservedClimate change has a major impact on agricultural production. By the end of this century, climate models project that Belgium will experience wetter winters and summers with prolonged dry periods. Rainfall events will become more intense. Especially drought-sensitive sandy soil is threatened by this climate change. Those soil types are frequent in the Flanders region of Belgium. This study helps to make soils more resilient against drought by using different types of compost. A pot experiment was conducted in the experimental greenhouses of ILVO-Ghent University to evaluate the application of different types of compost on soil physical properties of both sandy loam and loamy sand soils. Seven compost types have been investigated, including High-quality green compost (BC), vermicompost (VC), green compost (GC), fruit, vegetable and yard compost (FYVC), Spent mushroom compost (SMC), Manure compost (MC) and Bark compost (BC). The composts were applied in different doses, 350 kg N ha-1, 200 kg N ha-1 and, 350 kg N ha-1 + biofertilizer, and three ways of application were tested, incorporated, mulched or as compost tea. A soil without compost amended was used as control. The irrigation schedule adopted for the experiment was based on predicted climate data. In comparison to other application rates, the results showed that the highest application rate (3.5kgN ha-1) of applied composts has the most effective impact on water retention, dry mass, and water productivity in both soil types. Bio-green compost and spent mushroom compost had greater effects on lettuce productivity compared to others. Compost tea had shown no significant effect compared to the control in both soil types. Application of composts to sandy loam showed a greater effect on soil properties compared to loamy sand soils.Climate change has a major impact on agricultural production. By the end of this century, climate models project that Belgium will experience wetter winters and summers with prolonged dry periods. Rainfall events will become more intense. Especially drought-sensitive sandy soil is threatened by this climate change. Those soil types are frequent in the Flanders region of Belgium. This study helps to make soils more resilient against drought by using different types of compost. A pot experiment was conducted in the experimental greenhouses of ILVO-Ghent University to evaluate the application of different types of compost on soil physical properties of both sandy loam and loamy sand soils. Seven compost types have been investigated, including High-quality green compost (BC), vermicompost (VC), green compost (GC), fruit, vegetable and yard compost (FYVC), Spent mushroom compost (SMC), Manure compost (MC) and Bark compost (BC). The composts were applied in different doses, 350 kg N ha-1, 200 kg N ha-1 and, 350 kg N ha-1 + biofertilizer, and three ways of application were tested, incorporated, mulched or as compost tea. A soil without compost amended was used as control. The irrigation schedule adopted for the experiment was based on predicted climate data. In comparison to other application rates, the results showed that the highest application rate (3.5kgN ha-1) of applied composts has the most effective impact on water retention, dry mass, and water productivity in both soil types. Bio-green compost and spent mushroom compost had greater effects on lettuce productivity compared to others. Compost tea had shown no significant effect compared to the control in both soil types. Application of composts to sandy loam showed a greater effect on soil properties compared to loamy sand soils

Finite Element Analysis of Spur Gear Set

A Finite Element procedure has been developed in this work to determine the load distribution factor, Km, of the AGMA formula for a set of spur gear. At first, a spur gear with perfect involute is modeled using a 3-D CAD software. The model is them is assembled with shafts having 1, 2, and 3 degree misalignments. The generated 3-D models were in turn imported to ANSYS workbench to calculate the maximum bending and contact stresses using finite element method. The results generated were then compared with the maximum bending stress results obtained for parallel shafts to estimate the Load Distribution Factor Km. This study resulted in Km values of 1.03,1.11, and 1.1

Fabrication & testing of phase change material impregnated drywalls for thermal energy storage

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] This research illustrates the fabrication and thermal behavior of gypsum drywall containing phase change materials (PCMs), which could be used in the interior of a building envelope. The PCM used is a paraffin wax encapsulated in a polymer shell commonly known as microencapsulated PCM. The energy storing gypsum-PCM board has been characterized under simulated conditions for its thermal behavior in the thickness direction under various indoor and outdoor temperatures. Four different concentrations of PCM (7%, 12%, 20% and 25% W/W) were mixed in Gypsum to make board samples of 1-ft x 1-ft x 3/4-in and tested against a control board of gypsum with no PCM content. Thermal performance of PCM-gypsum boards was compared with the control board under the simulated summer conditions of about 93 degrees F outdoor temperature while the indoor conditions were about 67 degrees F. This research studies the effects of PCM-gypsum boards on energy savings by performing two test samples for every board; sample type 1 is where PCM-gypsum boards were tested against a control gypsum board with no PCM content, and Sample type 2 is a layered material of gypsum-1 in polystyrene and 0.5in wood backing where PCM-gypsum boards are tested against control board. A PCM-gypsum based Sample Type 2 was compared with one based in gypsum board only. Sample type 2 represents realistic wall structure. Under these conditions the temperature variation through the thickness of the gypsum board and heat flux in the thickness direction were measured. PCM-gypsum was a viable option for energy storage but needs better understanding of PCM behavior and its interaction with gypsum to further validate its schematics in building envelope.Includes bibliographical references (pages 96-98)

Nucleation and Growth of Crystalline Grains in RF-Sputtered TiO 2

Amorphous TiO2 thin films were radio frequency sputtered onto siliconmonoxide and carbon support films on molybdenum transmission electron microscope (TEM) grids and observed during in situ annealing in a TEM heating stage at 250∘C. The evolution of crystallization is consistent with a classical model of homogeneous nucleation and isotropic grain growth. The two-dimensional grain morphology of the TEM foil allowed straightforward recognition of amorphous and crystallized regions of the films, for measurement of crystalline volume fraction and grain number density. By assuming that the kinetic parameters remain constant beyond the onset of crystallization, the final average grain size was computed, using an analytical extrapolation to the fully crystallized state. Electron diffraction reveals a predominance of the anatase crystallographic phase

Not Available

Not AvailablePapaya (Carica papaya L., 2n = 18), a polygamous angiosperm, is a major fruit crop in tropical and subtropical regions. It is trioecious with three sex forms: male, female, and hermaphrodite, where sex determination is controlled by the XY chromosome pair with two slightly different Y chromosomes i.e. Y for male and Yh for hermaphrodite. Sex type determination in papaya, which cannot be determined either by embryo shape or morphology at the juvenile developmental stage, is an essential pre-requisite for crop improvement processes as it helps in identification of fruitful plants. Hence, molecular profiling could be used as an alternative that provides a quick and reliable identifi cation of sex types in plantlets at initial stages only. In the present study we have validated the sex linked sequence characterized amplified region (SCAR) marker W11 using PCR detection assay among different cultivars of papaya i.e. dioecious with either female or male and gynodioecious with either female or hermaphrodites and also performed a double-blind test for validating the seedlings of 84 F1 plants, which resulted in their sex determination. The assay clearly gives 800 bp band in male plants in dioecious types and hermaphrodite in gynodioecious plants.Not Availabl