Current Issue : July - September Volume : 2012 Issue Number : 3 Articles : 6 Articles
A complex interaction of controllable and uncontrollable factors is involved in aerial application of crop production\r\nand protection materials. Although it is difficult to completely characterize spray deposition and drift, these important factors\r\ncan be estimated with appropriate sampling protocol and analysis. Application height is an important variable influencing\r\noff-target spray drift, but this variable has not been easily measured or logged. A custom-configured aircraft-mounted laser with\r\nlogging capabilities makes this possible. This study was designed to investigate droplet size and deposition characteristics of a\r\nlow drift CP flat-fan nozzle at application altitudes 3.7 m, 4.9 m, and 6.1 m. In the study, CP flat-fan nozzles were set to a\r\ndownward angle of 30 degrees applying a mixture of water, Syl-Tac�® adjuvant, and Rubidium Chloride (RbCl) tracer at a\r\n28.5 L/ha application rate. Spray droplets were collected using water sensitive paper (WSP) cards placed in the spray swath.\r\nMylar sheets were also placed in the swath and downwind for drift sampling. Statistical analysis indicated that median droplet\r\ndiameter as determined by WSP in the spray swath was not significantly influenced by spray application height. Similarly,\r\nstatistical analysis also indicated that concentration of RbCl tracer from Mylar samplers in the spray swath was not significantly\r\ninfluenced by application height. Application height had a significant effect on spray deposition from drift samplers, along\r\nwith wind direction and relative humidity. Final results for drift samplers may have been influenced by shifts in wind\r\ndirection that altered the relationship between orientation of samplers and wind....
Conversion of papermill and sugar factory sludge into vermicompost is of double interest: on the one hand, a waste is converted into value added product, and on the other it controls a pollutant that is a consequence of increasing industrialization. This paper reports the changes in micronutrients in treatments treated with cow dung and biodynamic consortium (Jeevamrutha) during vermicomposting process. The result of this study reveals that the higher concentration of micronutrients found in treatments treated with cow dung than the treatment received with Jeevamrutha....
The potential negative effects of human activities on global climate have generated significant interests in recent years.\r\nReducing or offsetting carbon dioxide (CO2) emissions has been central to such discussion among and between state and federal\r\nregulatory agencies. Although emissions data from industrial, transportation and agronomic systems have been studied\r\nextensively, little data exists for managed ecosystems such as residential and municipal landscapes or sports turf facilities. Even\r\nthough these intensively managed landscapes are a significant component of modern agriculture in the United States, very little\r\nCO2 emission studies have been conducted on these systems. The objective of this study was to quantify energy inputs and the\r\ncarbon emissions of a standard size 18-hole golf course in California�s Central Valley, one of the most productive agricultural\r\nregions of the world. Carbon dioxide emissions from annual maintenance and carbon sequestered by soils and vegetation of\r\nsuch intensively managed ecosystems were also examined. These analyses included energy inputs required for equipment\r\nmanufacturing and subsequent annual fuel consumption from the use of equipment during daily operations. Our estimates\r\nindicated that the total energy requirement for this golf course was 1149 GJ year-1 or 13.1 GJ ha-1 year-1. The carbon emissions\r\ncalculated utilizing these energy input estimates indicated that this site also sequesters more CO2 than it generates during routine\r\nturfgrass maintenance operations....
The hydrolysis of lignocellulose is assumed to be the rate-limiting step in the anaerobic fermentation process. A\r\nfungal hydrolytic enzyme mixture was used to assess the enzymatic impact on different feedstocks for biogas production. The\r\noptimal conditions for enzymatic hydrolysis of rye grain silage, maize silage, grass silage, feed residues and solid cattle manure\r\nwere determined in lab-scale experiments. Finally, the effects of enhanced hydrolysis on anaerobic digestion were\r\ninvestigated in batch digestion tests. Enzyme treatment of substrate showed Michaelis-Menten-like behavior and reached\r\nmaximum values after 3 hours for reduced sugars as a product of hydrolysis. Methane production potential was determined\r\nfor specific feedstock mixtures without enzyme, with inactivated enzyme and with active enzyme (with and without buffer).\r\nThe results obtained show a clear increase in methane production after enzyme application for solid cattle manure (165 LN\r\nCH4�·kgODM\r\n-1 to 340 LN CH4�·kgODM\r\n-1 ), grass silage (307 LN CH4�·kgODM\r\n-1 to 388 LN CH4�·kgODM\r\n-1; enzyme plus buffer), feed\r\nresidue (303 LN CH4�·kgODM\r\n-1 to 467 LN CH4�·kgODM\r\n-1), maize silage (370 LN CH4�·kgODM\r\n-1 to 480 LN CH4�·kgODM\r\n- 1) and a lower\r\nincrease for rye grain silage (355 LN CH4�·kgODM\r\n-1 to 413 LN CH4�·kgODM\r\n-1). The ratios of heating values from methane yields to\r\nheating values from the dry materials ranged between 0.3 and 0.7 for the untreated feedstock and increased to levels between\r\n0.6 and 0.9 after the different forms of enzyme application....
In a forced convection solar dryer, the dryer efficiency is continuously changing during the drying process due to\r\nchanges of solar radiation and temperature. So, it is important to use a control system to optimize energy efficiency based on\r\nchanging drying factors. For this reason, a controller was designed, simulated and evaluated. In this research, fan speed was\r\nsimulated and controlled based on changing system variables accordingly to maintain the optimized efficiency. Fan speed was\r\nsimulated by SIMULINK toolbar of MATLAB software. The dryer efficiency was determined by considering the\r\nmathematical relations and monitoring the air temperature in 3 positions: inlet and outlet of collector and outlet of drying\r\nchamber. All experiments were carried out in three replications. The current and optimized dryer efficiencies were\r\ncalculated by using the control program. Results showed that the simulated model was capable of modeling fan speed. So,\r\nstatistical analysis showed that the control system highly improved the dryer efficiency throughout its operation at probability\r\nlevel of 1%....
Baled timothy hay underwent testing at a hay processing plant in Canada to determine if mechanical compression\n(rebaling) could be used as a disinfestation protocol for Hessian fly (Mayetiola destructor (Say)) puparia. Pressure sensitive\nfilms were randomly placed throughout the hay material, on the chamber walls, and in different orientations, to assess the hay\ncompaction unit�s ability to induce the required pressure to crash a Hessian fly puparium in the hay. Attached to the pressure\nfilms were organdy cages containing wheat seedlings infested with Hessian fly puparia. The variables which were tested\nincluded the hold time (0.5 and 2.0 s), applied pressure (10.34 and 12.41 MPa), and timothy hay quality (low-moisture first cut,\nhigh-moisture first cut and high-moisture second cut hay). A total of 36 tests were conducted. For each test, 10 Hessian fly\ncages and 10 pressure sensitive films were used. Each test cage contained approximately 168.56 Hessian fly puparia, translating\ninto a total Hessian fly count of 60681 for the entire field test. Analysis of the pressure sensitive films showed that 100% of\nthe hay experienced at least 200 kPa (29 psi) of pressure. Following the 75-day post experiment emergence period, 0.0066%\nof the puparia survived, which may be due to the fact that the emerged puparia might have not been crushed and not subjected\nto a pressure of at least 20.6 kPa. The applied pressures affected Hessian fly emergence by considerably reducing the number\nof puparia that emerged. However, Hessian fly emerged from one of the cages in two tests. Most of the Hessian fly puparia\nwere destroyed irrespective of the applied pressure, hold time or hay quality....
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