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Impact of Release Intervals and Densities of Trichogramma chilonis (Ishii) (Hymenoptera: Trichogrammatidae) Against the Sugarcane Stem Borer, Chilo infuscatellus (Lepidoptera; Pyralidae) under Field Conditions
Get PDFThe parasitization of Trichogramma chilonis parasitoids was found higher in the blocks where parasitoids were released to control Chilo infuscatellus at weekly interval (52.4 %) as compared to fortnight (40.9%) and monthly intervals (32.7%). Mean parasitization was (42.7%) when 80,000 thousand parasitoids were released on monthly basis followed by 41.4% (40,000), 37.8% (20,000) and 34.0% (10,000). However the mean infestation was below economic threshold levels ranging from 5.3 to 6.5 % in all the blocks where the parasitoids were released in variable numbers
Long Term Wind Trends Analysis of Coastal Belt of Pakistan
Get PDFPakistan has a long coastal belt, stretched over an area of more than 1000 km from Indian border in east to Iranian border in west, which has varying nature of geomorphic, geologic and climatic setups. In view to understand the characteristic nature of the area in relevance to undertake the wind energy assessment study, it is imperative to carry out the time-series climatic analyses especially for the wind parameters. Pakistan coastal belt has its unique windy nature because of the monsoon period in summer and land-to-sea wind behavior in winter, which further varies respect to coastal geomorphologic features. A research study has been conducted to analyze the long term wind speed trends for the salient cities lying near the coast of Pakistan. The seasonal decomposition technique, i.e. multiplicative model, was applied for the wind trend analyses using the wind data of 60 years for five major cities namely Karachi, Badin & Hyderabad in Sindh province and Lasbella & Ormara in Balochistan province. The present study describes the methodology adopted for the calculation of long term wind speed trends and subsequent the results indicate different wind variables of long term time-series analyses for the selected five cities
Economic and Technical Feasibility of Grain Chilling in Brazil
Get PDFGrain quality is critical due to the more stringent food-safety demands. Chilled aeration has become a popular technology for preventing grain spoilage during storage, mainly in warmer regions. However, a limiting factor in broad-scale adoption of chilling is the general belief that this technology is much more expensive than other post-harvest methods, such as the aeration with ambient air. In this work, ambient and chilled aeration were simulated considering the three major grain-producing regions in Brazil. Also, three storage capacities (95, 5000, 10500 t), five-grain types (corn, coffee, rice, bean, soybean), and two storage periods (beginning at the first and the last months of the harvest period) were used in the study, totalling 180 simulation scenarios. Based on these simulations a comparative cash flow analysis was performed aiming at evaluating the influence of the product, storage period, region, and silo size on the costs and profits from using these technologies. Results were strongly affected by the weather patterns of the studied regions, market values of grain, storage sizes, and fan operation hours. Chilled aeration should be economically competitive with ambient aeration, and the two technologies appeared as low-risk investments in Brazil, achieving average profits for 20 years by considering the time of money of US$ 68 and 59.4 million, respectively. Considering the technical factors, chilling presented higher energy consumption, but showed a greater potential for reducing grain temperatures and resulted in grain dry matter losses around 58% smaller than those verified when using ambient air
Isolation of a New Steroidal Glycoalkaloid from Solanum xanthocarpum
Get PDFA new steroidal glycoalkaloid was isolated from barries of Solanum xanthocarpum, together with two other known steroidal glycoalkaloids. The structure of new steroidal glycoalkaloid was elucidated as O-(3){ α-L- rhamnopyranosyl-(1→2gal)- β-D- galactopyranosyl}-solasodine on the basis of spectroscopic analysis as well as comparison with reported spectroscopic data of related compounds
Determining of Climatic Parameters Using CFD in Different Window Span in Naturally Ventilated Greenhouses
Get PDFThe aim of this study was to compare with the measured inner air temperature and relative humidity values and the simulated values determined with Computational Fluid Dynamics (CFD) in the naturally ventilated gable-roofed single glass greenhouse located North-South direction, having 45o and 90° window spans and under no cultivation.
The measured values were recorded every 2 hours from 8 am to 18 pm using the relative humidity and air temperature sensors placed in 7 different locations. Measurements were made in case of the 45° and 90° window span openness. For CFD simulations, the SolidWorks 2011 software was used. The values of air temperature and relative humidity inside the greenhouse were simulated depending on the outside ambient conditions and structural and physical properties of greenhouse. Then, the measured values were compared with the simulated values and error rate for each sensors were determined.
As a result, it was determined minimum error rates of the measured and simulated air temperature and relative humidity in greenhouses is 4.8% and 4.7%, respectively. The study showed that the CFD can be used as a powerful tool for determining inner climatic factors in naturally ventilated greenhouses
Dielectric Spectroscopy of Composites of Epoxy Resin
No full textThe dielectric behavior of composite of epoxies having different composition of prepolymer and epoxy equivalent is investigated in the frequency range 1E-1Hz to 1E5Hz at room temperature. The measurements presented consist of two sets of sample of epoxy resin with two different proportions 1:1 and 1:0.5 of resin and hardener. Samples having different proportion of resin and hardener shows low frequency dispersion (LFD) in the frequency range below 3 KHz at small thickness (less than 0.38mm). At large thickness the sample response is similar for the two different proportions
Radiation Induced Decoloration of Reactive Dye in PVA Films for Film Dosimetry
Get PDFThe investigation of film dosimeters made from polyvinyl alcohol (PVA) films dyed with methyl orange (MO) to enable their use in high dose radiation processing applications was studied. The dosimetric change in these films at pre and post irradiation was studied spectrophotometrically. Radiolytic bleaching was observed in PVA aided films exposed with Cs137 γ-source in dose range of 100-200kGy. The effects of pH, dye concentration and film thickness on the radiation response of the film dosimeters were discussed. The stability of MO-PVA films before and after exposure of radiation was also examined at ambient temperature and was found to be higher for long times at pre and post irradiation stages
New Approach in the Energy Analysis of an NH3-NaSCN Single Effect Absorption Machine (SEAM) with a Counter-Current Coaxial Tubes Internal Heat Exchanger (3CT-IHE)
No full textEnergy analysis provides the ability to assess performance and determine the size of equipment in a system. However, precisely integrating the thermal behavior of the component equipment makes it possible to better assess the performance of the system. This work highlights the influence of the thermal behavior of a 3CT-IHE on the performance and size of the equipment of SEAM with NH3-NaSCN as a working fluid. Based on equations of conservation balances of mass, species and energy, the energy analysis made showed that depending on the magnitude of the heat flows of the weak and strong solutions involved in the heat exchange at the level of the 3CT-IHE, there are different temperature ranges for which the weak solution or the strong solution governs the heat transfer, thus giving rise to the notions of “thermal heating efficiency” and “thermal cooling efficiency” respectively. The results obtained were compared with those of Sun. This new approach has demonstrated better performance of the SEAM for the same operating conditions. It has also been shown that it is possible to increase the temperature of the generator above 90 °C without resorting to another working fluid and that in the case of subjecting NH3-NaSCN to supercritical conditions in temperature at the generator; it is possible to obtain a machine COP greater than 1 and an even smaller pump size
Pressure Prediction by Programme Logic Control Approach on Superplastic Forming in 7075 Al Alloy
Get PDFA widespread problem in a superplastic forming process is to obtain a uniform thickness distribution in multiple geometry components. Hence, nowadays, the variable pressure control approach has been implementing in order to obtain uniform thickness variation in complex profiles. This paper observed the outcome of various stages in the superplastic forming process for multistage hemispherical die cavity in a newly developed pressure prediction method. Superplastic behaviour such as forming pressure, forming temperature, forming time and thickness distribution are analysed and optimised all parameters in multi-stage profile by using a new pressure prediction approach. Experimentally and numerically evaluated the superplastic parameters and the values are obtained from finite element methods agrees well with the experimental results
Geoelectrical Investigations at Three Bridge Sites, North Nyala, Southern Darfour State, West-Sudan
Get PDFResistivity measurements were carried out to delineate the depth of the basement rocks (bedrock) and the lithology of the overlying sediments for the purpose of bridges construction route. The survey was conducted at three sites: Andro, Duma and Manwashi, north Nyala, Southern Darfur State, Western Sudan. These sites (Andro, Duma and Manwashi ) are located along Nyala _ El-Fashir road at a distance approximately of 15km, 42km and 75km from Nyala (respectively). The surface geology of the area is dominated by the basement complex rocks which are overlain by thin layer of superficial deposits
The modeling of the VES data was done using IX1D software. The final results of the modeled and interpreted resistivity data are presented in the form of geoelectrical sections. These sections have shown a close agreement with the geological and hydrogeological conditions of the area. Three zones were identified in these sections, they are the top dry zone (<1m to >3m) representing the superficial deposits, the middle zone (Saturated zone) represents the groundwater aquifer. It varies in lithology from weathered and cracked basement rocks to the Alluvial deposits with a significant heterogeneous nature which varies from clayey, silty, sandy, pebbly and boulders layers. The bottom zone (Fresh basement rocks) represents the bedrock. It indicate an increase of hardness and compaction from Andro , Duma and Manshawi sites respectively. These findings can be used successfully for constructions the bridges of the three sites