Evaluation of Soil/Material Interface Friction and Adhesion of Akure Sandy Clay Loam Soils in Southwestern Nigeria

There is the need to develop appropriate and efficient soil engaging tools and implements to optimize energy required to cultivate the land and enhance agricultural productivity and sustainability in Nigeria. Necessary design data which were hitherto scarce for Nigerian soils are therefore required to accomplish the task effectively. Laboratory investigations were carried out to evaluate angle of soil/material friction and coefficient of soil/ material friction necessary in the design of soil-engaging tools and implements. Facilities used in the investigation include soil-material friction device or sliding shear apparatus. Three types of soil investigated were sandy clay loam soils. The structural materials’ surfaces investigated were rubber (RUB), steel (SST), galvanized steel (GAS) and Teflon (TEF). Results show that the coefficient of soil/material friction increased with moisture content to a limit and thereafter decreased. For the materials tested the range was 0.13 - 0.85 in the three soil textures and can be described by polynomial equations for the purpose of prediction. Rubber had the highest coeffi cient of soil/ interface friction followed by smooth steel, galvanized steel, while Tefl on had the least in that order.Key words: Soil; Coeffi cient of friction; Materials; Soil/ tool interface; Adhesion; Model

Evaluating coefficient of performance and rate of moisture loss of some biomass humidifiers materials with a developed simple direct stand-alone evaporative cooling system for farmers

© 2022 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)The purpose of this study was to investigate the feasibility of deploying direct evaporative cooler with Jute fiber, palm fruit mesocarp fiber and wooden charcoal as humidifier in Nigeria. High cost of imported evaporative coolers and humidifiers can discourage farmers and limited adoption of evaporative cooling technology. For this purpose an experimental direct evaporative cooling test rig was developed and assembled in south western Nigeria with biomass humidifier. The evaluation parameters were the humidifying efficiency, the rate of moisture loss, coefficient of performance and sensible heat ratio. The humidifier presented average cooling efficiency of 55.9 to 78.62 %, average rate of moisture loss of 1.37 × 10 -3 to 2.61 × 10 -3 kg/s, average COP of 8.48 to 23.42 (EER of 11 to 78) and average sensible heat ratio of 1.28 × 10 -4 to 4.06 × 10 -4 for the air velocity of 3.0 to 4.5 m/s. The obtain performance can be better in a dryer month or nearly impossible in a very wet month as the humidifying efficiency of direct evaporative coolers are found to diminish at high humidity. To avoid casting doubt on the effectiveness of direct evaporative cooler by farmers, it should only serve as stop gap preservation equipment and deployed during the favorable weather condition especially during the winter when the air is dry. These can be identified from the metrological charts of the chosen location.Peer reviewe

Trace Elements Status and Strength of Compacted Arable Soils of Akure Nigeria

Trace elements in arable soils have become an environmental issue that it has to be investigated for sustainable agricultural production. Investigations were carried out in the laboratory to determine some physical, geochemical and mechanical properties of three (A, B, and C) arable soils. The properties investigated were shear strength, and trace elements status in the surface and subsurface horizons. Shear vane tester was used to measure soil shear strength and atomic absorption spectrophotometer was used to determine the trace elements status of the soils. The three profiles studied were predominantly clay loam in texture across the horizons except the profile B which was clay in the 30 - 40 cm depth layer. The specific gravity of the experimental soils ranged from 2.65 to 2.77. The plasticity index of the profiles A, B and C ranged from 8.6 to 10.7, 9.3 to 10.7 and 10.0 to 10.7, respectively. The soils were characterized by relatively low levels of identified trace elements. Results showed that 8.5 mg/Kg of lead (Pb) was the highest value of trace elements, while 0.3 mg/ Kg of Iron (Fe) was the lowest value of the soil trace element observed. The most notable characteristics of the soils were the low organic matter content and the predominantly acidic pH. The bulk density of the sample varied between 1.72 and 1.86 g/cm3. The range of the maximum shear strength of compacted soil was 150.75 to 156.14, 154.79 to 160.17 and 162.87 to 166.90 kPa for profiles A, B and C, respectively. The mean moisture content during the study varied from 14.5 to 18.9% (db). The data presented in this study is good for planning and soil management practice.Key words: Soil properties; Trace elements; Shear strength; Moisture content; Soil profil

Development of an active evaporative cooling system for short-term storage of fruits and vegetable in a tropical climate

An active evaporative cooler for short-term storage of fruits and vegetable has been developed to improve the shelf life of fruits and vegetables for small holder farmers in Southern Nigeria.  The evaporative cooler uses palm fruit fiber as cooling pad material which is considered a waste in palm oil production in Nigeria and consists of three suction fan, automatic water control switch, water pump and evaporative cooling chambers.  The performance of cooler was evaluated in terms of temperature drop, efficiency of the evaporative cooling and cooling capacity.  The temperature drop ranged from 40C to 130C while the relative humidity of the ambient air was increased to 96.8%.  The cooler could drop the temperature close to wet bulb depression of ambient air and provided up to 98% cooling efficiency with a maximum cooling capacity of 2,529 W.  At an ambient temperature of 370C, the evaporative cooler provided the storage conditions of 23.2 temperature and 85.6% – 96.8% relative humidity, which can enhance the shelf life of wide range of fruit and vegetables of moderate respiration rates.  The power consumption of the cooler was half that of a typical vapour compression refrigerator of the same volume.   Keywords: cooling capacity, cooling efficiency, evaporative cooling, temperature drop cerun:yes'> A throughput capacity of 66.06 kg h-1 was obtained at moisture content of 12.5% wet basis and 405 r min-1 while throughput capacity of treadle thresher was 55.51 kg h-1 at moisture content of 17% wet basis and 610 r min-1.    Keywords: cowpea, mechanical damage, moisture content, threshing efficiency, variet

Draught and Soil Disturbance of Model Tillage Tines Under Varying Soil Parameters

Rosana G. Moreira, Editor-in-Chief; Texas A&M UniversityThis is a paper from International Commission of Agricultural Engineering (CIGR, Commission Internationale du Genie Rural) E-Journal Volume 9 (2007): Draught and Soil Disturbance of Model Tillage Tines Under Varying Soil Parameters. Manuscript PM 06 016. Vol. IX. March, 2007

Soil Compaction Caused by Traffic Frequency of Rubber-Tracked Excavator

The project site described in this study was assumed to have been subjected to induced compaction of the excavator that was used to clear the land. It was therefore necessary to estimate the compaction so induced. The experimental soil was a sandy clay soil. The main objective of this study was to evaluate the soil compaction induced by traffic of rubber- tracked, medium size Excavator, 31.9 KW power and 36.4 KN weight in a sandy clay soil. The study was conducted at the Experimental site of the STEP B project of the Federal University of Technology. Akure (FUTA), Nigeria. The experimental soil was subjected to 1. 3, 5, 7, 9 and 11 passes of the Excavator. Variables measured include penetration resistance (PR), bulk density (BD), and rut depth (RD). The variables were monitored at the centre lines of the left (L) and right(R) tracks of the Excavator. Results showed that means of the L and R values were not significantly different at the 5% level of significance. Mean values of the PR in the depth range of 0 to 30 cm were 1102.85, 1363.65, 1163.5,1269.60, 1315.05 and 1428.8 kPa for 1,3,5,7,9 and 11 passes respectively. PR increased with depth to a limit and then reduced in value in the range of depth considered. The maximum PR value occurred between 15 and 20 cm depth. The average PR value before the excavator passes (control) was 420 kPa which was significantly different from those after the passes. The range of rut depth corresponding to 11 passes was 4.6 and 14.8 cm. The moisture content during the experimentation ranged from 11.5 - 15.5% (db) in the depth range. ,&nbsp

Soil Compaction Caused by Traffic Frequency of Rubber-Tracked Excavator

The project site described in this study was assumed to have been subjected to induced compaction of the excavator that was used to clear the land. It was therefore necessary to estimate the compaction so induced. The experimental soil was a sandy clay soil. The main objective of this study was to evaluate the soil compaction induced by traffic of rubber- tracked, medium size Excavator, 31.9 KW power and 36.4 KN weight in a sandy clay soil. The study was conducted at the Experimental site of the STEP B project of the Federal University of Technology. Akure (FUTA), Nigeria. The experimental soil was subjected to 1. 3, 5, 7, 9 and 11 passes of the Excavator. Variables measured include penetration resistance (PR), bulk density (BD), and rut depth (RD). The variables were monitored at the centre lines of the left (L) and right(R) tracks of the Excavator. Results showed that means of the L and R values were not significantly different at the 5% level of significance. Mean values of the PR in the depth range of 0 to 30 cm were 1102.85, 1363.65, 1163.5,1269.60, 1315.05 and 1428.8 kPa for 1,3,5,7,9 and 11 passes respectively. PR increased with depth to a limit and then reduced in value in the range of depth considered. The maximum PR value occurred between 15 and 20 cm depth. The average PR value before the excavator passes (control) was 420 kPa which was significantly different from those after the passes. The range of rut depth corresponding to 11 passes was 4.6 and 14.8 cm. The moisture content during the experimentation ranged from 11.5 - 15.5% (db) in the depth range

PHYSICAL PROPERTIES OF SOYBEAN (VAR TGX 1019-2EB)

Soybean (var TGX 1019-2eb) is one of the improved varieties that were developed by international institute for tropical agricultural (IITA), Ibadan a few years ago. This paper reports the effect of moisture content on the physical properties of the soybean cultivar. The average length, width, thickness and geometric mean diameter of the grain varied from 7.37 to 9.96, 6.48 to 7.45, 5.33 to 5.54 and 6.33 to 7.39cm respectively as the moisture content varied from 6.7to 47.1% (db). One thousand grain mass varied from 130.67 to 180.21g in the same moisture content range. The bulk density, seed density and sphericity decreased from 0.7285 to 0.6034 gmcm1, 1.1570 to 0.952 gmcm1 and 0.860to 0.749% respectively in the moisture content range. Porosity, surface area and volume of the grain increased from 0.2346 to 0.4233%, 1.262 to 1.715cm2 and 0.145 to 0.195cm1 respectively in the same moisture content range of 6.7 to 47.1%. the static coefficient of friction increased on three structural surfaces, namely plywood parallel to grain (0.4877 to 0.6249), plywood perpendicular to grain (0.4922 to 0.6876) and galvanized steel (0.3839 to 0.5774) as the moisture content increased from 6.7 to 47.1%. similarly the of repose increased from 25.87 to 32.45 degrees in the same moisture content range. The above principal findings would be helpful in the design and development of handling, processing and storage equipment of this variety of soybean