Effect of Ammonium Sulphate on Dielectric Properties of Soil at X & J-Band Microwave Frequency

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Effect of Ammonium Sulphate on Dielectric Properties of Soil at X & J-Band Microwave Frequency International Journal of Recent Technology and Engineering (IJRTE) ISSN: 2277-3878, Volume-8 Issue-4, November 2019 Effect of Ammonium Sulphate on Dielectric Properties of Soil AT X & J-Band Microwave Frequency Syeda Ruhi Nishat, Gulam Rabbani, H.C. Chaudhari, Y.H.Shaikh Abstract: Microwave play important role in the moisture detec- have measured the complex dielectric constant of soils as a tion of soil plant and other agricultural product. In present paper function of water content and temperature over the fre- the study of effect of ammonium sulphate on microwave dielec- quency range from 0.1 to 26 GHz .Peplinski N. R. et al. [4] tric properties of soil is presented. For this three soil samples also studied the dielectric constant ε' and dielectric loss ε" of were collected from different geographical region of Maharash- tra. The infinite sample method was employed for the determina- four soil types having various moisture contents in the fre- tion of storage factor (ε’) and loss factor (ε”) of the soils. In this quency range between 0.3GHz and 1.3 GHz In a detailed paper the effect of ammonium sulphate on dielectric properties of study, Sengwa R. J. and Soni A. [5] have reported the varia- soil when X and J-band microwave frequencies incident on it is tion of dielectric constant with density of dry minerals of discussed. The variation in values of dielectric properties of these soil at 10.1 GHz. Chaudhari H. C. and Shinde V. J. [14] soil samples mixed with different chemical contents are then have reported that the dielectric properties of dry soil at measured at frequency 6 GHz and 9.86 GHz. The concentrations microwave frequency in X- band are function of its chemi- of this chemical in the soil samples are increased from 0 to 12 % cal constituents and physical properties. Calla O. P. N. et al. and results are presented. [16] have studied the variability of dielectric constant of dry Keywords: Dielectric parameter, microwave frequency, X and J- soil with its physical constituents at microwave frequencies. band, ammonium sulphate. II. SAMPLE PREPARATION I. INTRODUCTION For preparation of soil samples three samples were col- There are different types of waves present in electro- lected having textural difference from Maharashtra state. magnetic spectrum. Out of these waves microwave has its Soils were first sieved by standard sieve. The sieved out soil vast importance. From cooking popcorn to study the galax- are then oven dried to a temperature around 180oC for half ies they are being used in different ways. Microwave elec- hour in order to completely remove any trace of moisture. trical properties of material provide information about mate- Soil samples of 4% gravimetric moisture contents are pre- rial characteristics. The natural nutrients found in the soil pare by adding an accurate amount of distilled water to the essential to plant growth, such as nitrogen, phosphorus and known mass of the oven dry soil. The soil samples are then potassium, are manufactured synthetically from inorganic prepared by mixing different concentration of ammonium material and applied to soil in the form of chemical fertiliz- sulphate in 4% distilled water and this mixture is then added ers. Although chemical fertilizers improve the growth of to soil. These mixtures are kept in air tight sealing bags and plants and increase the yields of fruits and vegetables in a allowed for few hours to facilitate internal drainage, ho- relatively short period of time. Many researchers have re- mogenous mixing and proper settlement. These soil samples ported the results of their studies on the variation of dielec- are then inserted into the solid dielectric cell for measuring tric characteristics of fertilized soils at microwave frequen- their dielectric properties. The concentrations of chemical cies. Wang J. R. and Schmugge T. J. [1] estimated that the are varied over a range from 0 to 12 %. Physical and chemi- dielectric constant is directly related to pore- space of soil. cal analyses have been done in government agriculture of- H.C.Chaudhari and V. J. Shinde [2] studied the dielectric fice shahnoorwadi Aurangabad and institute of science Au- properties of black and red soil. They concluded that the rangabad. dielectric properties of soil varied with varying moisture, temperature, density as well as other physical and chemical III. MEASUREMENT OF DIELECTRICPROPER- properties. Also the existence of bound water in sol water TIES mixture significantly affects the electrical properties of soil. Hoekstra P. and Delaney A [3] The infinite sample method is used to determine the dielec- tric properties of the soil samples. An X-band and J-band microwave set-up in the TE10 mode with klystron source operating at frequency 9.86 GHz and 6GHz respectively. Experiments were performed at room temperatures. The signal generated from the klystron is incident on the soil Revised Manuscript Received on November 15, 2019 sample. The soil reflects part of the incident signal from its Dr. Gulam Rabbani, Associate Professor And Head Department Of front surface. The reflected wave combined with incident Physics Maulana Azad College Of Arts, Science And Commerce, Auran- wave results in a voltage standing wave pattern. These gabad. Dr Yusuf H. Shaikh, Associate Professor Shivaji Arts, Commerce And standing wave patterns are then used in determining the val- Science College Kannad; Dist. Aurangabad. ues of shift in minima resulted due to before and after inser- Dr.Harish Chaudhari, Professor Department Of Physics, J.E.S. College tion the sample. Jalna. Syeda Ruhi Nishat pursuing Ph.D Physics Dr Babasaheb Ambedkar Marathawada University, Aurangabad. Published By: Retrieval Number: C5871098319/2019©BEIESP 64 Blue Eyes Intelligence Engineering DOI:10.35940/ijrte.C5871.118419 & Sciences Publication Effect of Ammonium Sulphate on Dielectric Properties of Soil AT X & J-Band Microwave Frequency The dielectric constant ε' and dielectric loss ε'' of the soils Table 1 Variation of dielectric properties of soil at x and are then determine J-band microwave frequency for soil sample 1 for differ- ent concentration of NH4SO4 NH4SO4 9.8 GHZ 6 GHZ from the following relations: % ε' ε'' ε' ε'' 휆푐 2 2 2 2 2 2 0 1.8161 0.072 2.2261 1.9432 1 휆푔 (푟 − 퐸 ) 1 − 푟 퐸 + 2푟퐸 ) 휀′ = + 3 1.9976 0.0779 2.398 2.0703 휆푐 2 휆푐 2 1 − 푟2퐸2 + 2푟퐸 2 1 + 1 + 6 2.0865 0.098 2.4207 2.1607 휆푔 휆푔 9 2.1642 0.1025 2.4427 2.2552 휆푐 2 12 2.2586 0.114 2.626 2.3041 2푟퐸( 1 − 푟2퐸2 − 푟2 − 퐸² ) 휀′′ = 휆푔 휆푐 2 1 − 푟2퐸2 ² + 2푟퐸 2 Table 2 Variation of dielectric properties of soil at x and 1 + 휆푔 J-band microwave frequency for soil sample 2 for differ- ent concentration of NH4SO4 Where, NH SO 4 4 9.8 GHZ 6 GHZ % a=width of waveguide ε' ε'' ε' ε'' λg = guide wavelength 0 2.1787 0.1786 2.6195 0.0319 D= position of first minima with sample 3 2.3925 0.2246 3.0742 0.0411 6 2.4508 0.2285 3.1511 0.0432 DR= position of first minima without sample (with short) 9 2.509 0.2413 3.2308 0.0433 K=2π/λg 12 2.5698 0.255 3.3137 0.0455 r= VSWR Table 3 Variation of dielectric properties of soil at x and λc = cut off wavelength of the wave guide=2a J-band microwave frequency for soil sample 3 for differ- ent concentration of NH SO IV. EXPERIMENTAL TECHNIQUE 4 4 NH4SO4 9.8 GHZ 6 GHz % The experimental technique used to measure dielectric prop- ε' ε'' ε' ε'' erties of soil is infinite sample method. The X and J-band 0 1.7434 0.1001 2.5558 0.0916 microwave set up is used for these measurements. The di- electric constant, dielectric loss is measured at two different 3 1.811 0.1081 2.7941 0.09 frequencies viz 9.8 GHz and 6 GHz at room temperature. 6 1.8442 0.1096 2.8592 0.0928 The soil sample is collected from agricultural areas outside 9 1.8775 0.1154 2.9268 0.0957 Aurangabad city. The sample is collected in hot summer 12 1.9133 0.1168 2.9974 0.0968 with negligible water percent. The sample is the mixture of sand, silt and clay with high percentage of sand. The soil TABLE 4 PHYSICAL AND CHEMICAL PROPER- sample of known volume was placed in sample holder TIES OF SAMPLE 1, 2 & 3 which is on the opposite end of the microwave source.. The Soil composition sample 1 sample 2 Sample 3 microwave power is recorded for different slot position of microwave bench. About 95 points are recorded for each Sand 98.175 83.45 91.05 Slit 0.585 6.54 3.48 concentration of ammonium sulphate (NH4SO4) clay 0.7 10.01 5.47 Water holding capac- 35 22 32 ity (WHC) Bulk density 1.04 1.43 1.19 Particle density 0.061 0.531 0.269 Porosity 28.82 13.27 15.26 Volumetric water 3.74 8.85 16.35 content (VWC) Gravimetric water 1.937 4.712 9.29 content(GWC) Fig 1 Experimental setup of X-band microwave bench for Organic carbon (OC) 0.33 0.32 0.28 measurement of dielectric properties of Soil. Copper (ppm) 2.96 3.4 5.7 Iron (ppm) 1.86 2.16 6.68 V. RESULT AND DISCUSSION: Manganese(ppm) 3.14 0.84 2.44 Zinc (ppm) 0.3 1.56 2.1 The physical and chemical analysis report of Aurangabad Phosphorous (kg/ha) 21.53 19.35 18.39 soil is presented in table 4.
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