The development of the instrumentation and control system for a palm kernel nuts drier

The electronic instrumentation system for a palm kernel drier was designed, constructed, tested and found to perform satisfactorily. Type K thermocouple was used to monitor the temperature of the drying chamber. A control circuit for presetting and regulating the temperature of the drier was also developed. This permits the temperature of the drying chamber to be fixed between ambient temperature and 100°C. Keywords: thermocouple, elecronic instrumenetation, control circuits, drier Nigeria Journal of Pure and Applied Physics Vol. 4(1) 2005: 46-5

Design And Performance Characteristics Of Palm Kernel Nuts Drier

A cabinet drier with dimensions 0.82m x 0.45m x 0.52m, having four trays and capable of drying 4kg of palm kernel nuts per hour was constructed. A control circuit to regulate the temperature of the heating chamber was installed in the appropriate parts of the drier. Using electrical heating, hot air is produced and allowed to flow through the product in order to remove the moisture. The drier was heavily lagged to conserve heat. The electronic instrumentation section of the drier has a digital display unit that allows the temperature of the drying chamber to be read. This drier was found to work satisfactorily, achieving complete drying of the nuts within the temperature range of 80oC to 100oC under 60 minutes of its operation without discolouration of the nuts or the resultant extracted oil. The maximum production requirement was 40kg per day on the basis of an 8- hour shift. The drier is also suitable for drying several agricultural products under varying temperature condition. Key words: control circuit, cabinet drier, agricultural products, temperature, digital display. Nig. J. of Pure & Appl. Physics Vol.3 2004: 8-1

An Investigation Into The Effect Of Mixtures Of Lateritic-Cement And Other Naturally Occurring Materials For The Production Of Building Bricks

The behaviour of the laterite-cement, shale, and limedust when mixed in proportions to mould bricks under natural conditions and the improvement of structural properties of laterite for wider and more economical usage as construction material were investigated. Shale was found to be a very poor soil stabilizer because it reduces even the physical quality or property of the original lateritic soil. With limedust little or no improvement was observed better than if only laterite has been used to make bricks. It is found however, that using laterite stabilized with very little cement (that is 5 to 20% cement) gives strong, durable and relatively cheap bricks that can either be used for non-load bearing walls or load bearing walls. Key words: laterite-cement, limedust, structural properties, bricks Nig. J. of Pure & Appl. Physics Vol.3 2004: 45-5

Superconductivity in MBE grown InN

We present the experimental investigation of superconductivity in unintentionally doped MBE grown InN samples with various InN film thicknesses. A significant change in resistivity was observed at 3.82 K, for an 1080 nm InN layer with carrier concentration n3D=1.185x1019 cm-3. However, no significant resistance change was observed in the case of InN samples with carrier density of 1.024x1019 cm-3, 1.38x1019 cm-3, and thicknesses of 2070 and 4700 nm, respectively. The carrier density of all investigated samples was within the range of values between the Mott transition (2x1017 cm-3) and the superconductivity to metal transition (7x1020 cm-3). We believe that at lower temperatures (3He) which we cannot achieve with our set-up, the phase transition in other samples is likely to be observed. The origin of the observed anisotropic type-II superconductivity is discusse