Development of a Millet Destoner for Small Scale Farmers

Post-harvest processes of millet rely on labour-intensive manual operations in Nigeria while its produce is associated with contaminants. A manually-operated destoner was developed to increase grain value for commercial production and reduce drudgery. To construct the destoner sieves, physical properties of one thousand randomly selected grains were determined digital Vernier callipers. Millet grains to be destoned was fed through the upper portion of the destoner being operated through the crank handle while the pure grains were collected at the discharge outlet. Results obtained shows the geometric diameter of the grains increase progressively from 3.51-4.22mm as moisture content increases. A screen aperture of 3.5mm was constructed. Grains’ surface area, volume and sphericity increased from 22.67-34.82mm², 8.19-13.98mm³ and 0.691-0.776g respectively. Mass, true density and terminal velocity of 1000 seed increased from 13.56-43.84g, 1548.91-1689.87kg/m³ and 2.69-4.58m/s respectively. The bulk density of millet also increased as moisture content increases but decreased beyond 12.5% moisture level indicating that millet floats on water and was transpoted with the aid of an auger. About 50kg of millet was poured into the destoner to occupy its ⅓ capacity while the remaining ⅔ was filled with water. Destoner output was at 95% efficiency.Key words: Destoner, Millet, Processing, Properties, Contaminants

Effect of Moisture Content on Sunflower Seed Physical and Mechanical Properties

This study was carried out to measure some physical and mechanical properties of the sunflower seeds variety “DW667”. The physical properties (length, width, thickness, equivalent diameter, sphericity, surface area of seed, one thousand seed mass, bulk and true density, porosity) and mechanical properties (compressive load and displacement deformation for vertical and horizontal orientations) were measured at 4%, 10%, 15%, 20% and 25% Dray basis (d.b.) moisture contents. Higher moisture content from 4%to25% increased length, width, thickness, equivalent diameter, sphericity, surface area of seed, one thousand seed mass, bulk and true density, porosity and deformation displacement at the vertical and horizontal orientations of seeds increased from 10.57 to , 4.50 to , 2.85 to , 5.13 to , 49 to 50 %, 82.95 to 94.53 mm2, 33.70 to , 286.80 to 314.98 kg/m3, 406.47 to 483.61 kg/m3, 29.22 to 34.54 %, 1.63 to 2.63 mm and 0.70 to 1.87 mm, respectively. While the required compressive force for rupture seeds decreased from 25.3 to 12.39 N and 11.5 to 5.63 N for vertical and horizontal orientations, respectively with moisture contents uprising from 4 to 25 %. The findings of this study will open new windows in farm mechanization for the designing and improvement of treatment machines for this type of seed.

Modelling the Pleistocene colonisation of Eastern Mediterranean islandscapes

Predictive models have become an integral part of archaeological research, particularly in the discovery of new archaeological sites. In this paper, we apply predictive modeling to map high potential Pleistocene archaeological locales on the island of Cyprus in the Eastern Mediterranean. The model delineates landscape characteristics that denote areas with high potential to unearth Pleistocene archaeology while at the same time highlighting localities that should be excluded. The predictive model was employed in surface surveys to systematically access high probability locales on Cyprus. A number of newly identified localities suggests that the true density of mobile hunter-gatherer sites on Cyprus is seriously underestimated in current narratives. By adding new data to this modest corpus of early insular sites, we are able to contribute to debates regarding island colonisation and the role of coastal environments in human dispersals to new territories.

Moisture Dependent Selected Engineering Properties of Deenanath Seeds in Relation to Development of Processing Machinery

Propagation of grasses through seeds is important in view of vigour and germination. Various grasses as Pennisetum pedicellatum Trin., Cenchrus ciliaris L., Chrysopogan fulvus have lower vigour and germination, due to which they need specific operations as defluffing, separation of true seeds, cleaning and grading by specific machines. In designing a machine for a specific use, physical properties and their behaviour with moisture play an important role. A study was conducted to assess the effect of moisture content at five levels [6.88 - 19.23 %, (d.b.)] on selected physical properties of defluffed Deenanath grass seed. The length, width, thickness, arithmetic mean diameter, and geometric mean diameter of defluffed Deenanath seed increased from 2.30 mm to 2.56 mm, 0.71 mm to 0.96 mm, 0.47 mm to 0.63 mm, 1.16 mm to 1.38 mm, and 0.90 mm to 1.15 mm, respectively, with increase in moisture content 6.88 % to 19.23 %. Bulk density, true density, and porosity decreased from 652.16 kg.m-3 to 585.78 kg.m-3, 852.63 kg.m-3 to 792.71 kg.m-3, and 25.62 % to 24.97 %, respectively, with increase in moisture content from 6.88 % to 19.23 per cent. The aspect ratio, sphericity, surface area, volume, and thousand-seed mass of the seed were in the range of 30.91 - 37.51 %, 0.39 - 0.45, 2.58 - 3.23 mm2 , 3.71 - 4.97 mm3 , and 0.480 - 0.523 g, respectively. Linear relationships with correlation coefficients higher than 0.90 were observed for the physical properties over the experimental range of moisture content.

The Effect of Nanostructured Zirconia Reinforcement on the Mechanical and Structural Properties of a Copper-Based System

Powder technology has a great impact on the industry and the need for the labor market since this technology has been used to manufacture copper-based composition models with a fixed rate of 5% of (SiC) with nanostructuring of (0,5,10,15,20) %. Regarding nanoscale zirconia (ZrO2), the mineral and ceramic powders were grinded with a grinding time of two hours for the purpose of homogeneity, then the powders were pressed at a pressure of 5 tons and a time of one minute only. Later, the properties were studied and the prepared samples were sintered at 900 °C for two hours.. The physical properties were represented by density and porosity, mechanical properties by compressive strength (samples failed) and wear and structural properties by SEM and EDS. The results showed that the true density and real porosity decreased with the increase in the size of the support ratios, while we noticed an increase in compressive strength with the increase of the added nanoscale ratios. As for the wear, its value decreased to reach the lowest value after sintering and at the ratio of 15% zirconia. Furthermore. the results of the scanning electron microscope showed that the ratio of 15% zirconia is the best percentage in terms of improving physical and mechanical properties. Keywords: nanozirconia, compressive strength, Thermal sintering, porosity.

MEMPELAJARI KARAKTERISTIK FISIK BIJI KAKAO (Theobrema cacao L.) PADA SUHU PENGERINGAN YANG BERBEDA

Drying is a common process step for agricultural grain products for ease of handling and to achieve the desired quality levels. One of the commodities that have high economic value produced by farmers in Lampung Province is cocoa beans. The drying process may change the physical properties of the cocoa beans and affect the processing of cocoa beans at a later stage. This study aims to determine the effect of drying temperature on changes in the physical properties of cocoa beans such as dimension, volume, weight, surface area, true density, bulk density, porosity, sphericity, and angle of repose. This research was applied to fresh non-fermented cocoa beans in testing. The cocoa beans were dried at temperatures of 40, 50 or 60oC. The research data were then statistically tested using paired sample T-Test at the 95% level to determine whether there is any effect of drying temperature on changes in its physical properties. The results showed a significant effect of drying temperature on weight, volume, geometric mean diameter (Dg), surface area, bulk density, porosity, and angle of repose of cocoa beans. Meanwhile, the sphericity and true density parameters did not significantly change. Keywords: cocoa beans, drying, physical properties

Synthesis and Characterization of Soft Magnetic Materials NixZn1-xFe2O4 (x = 0,2 – 0,8) Lombok Iron Sand with Co-precipitation Method

The synthesis of soft magnetic NixZn1-xFe2O4 with variations in composition (x = 0,2 – 0,8) by the co-precipitation method has been carried out. The research objective was to determine the effect of x variation on the crystal structure, microstructure, magnetic properties, and density. The samples were characterized by their crystal structure using XRD, microstructure using FE-SEM, magnetic properties using VSM, and physical properties (True Density). The XRD analysis results obtained two phases, the major phase is nickel-zinc ferrite, and Fe2O3 shows as the minor phase. The crystal size increased and the lattice parameters decreased with the increase in nickel content. The results of FE-SEM analysis at x = 0.2 are spherical in shape with an average particle size found about 47.07 nm. The results of VSM analysis showed that the increase in nickel content, the higher the magnetization saturation value, and the super-paramagnetic properties of all samples obtained. The results of the analysis of physical properties show that true density decreases with an increase of nickel content in each sample.

The Obtaining Solid Electrolytes "Ionic Salt-Natural Zeolite"

The technology of obtaining solid electrolytes by mechanochemical method with subsequent cold pressing from inexpensive common clinoptilolite rocks and ionic salts – sodium and ammonium hydrophosphates at varying ratios of the initial components and the duration of mechanical activation is presented. Their physical and transport properties, namely, true density, hygroscopic humidity, specific surface according to Tovarov, volumetric electrical conductivity were found. Promising samples for further research were created, recommended for use as solid electrolytes.