Characterization of magnetic field horizontal component in selected stations along the 210o MM

Characterizing the magnetic field horizontal component (H) variability helps to better accommodate the irregular fluctuations inthe electron/ion density of the ionosphere for mitigating short-wave radio communication and Global Navigation Satellite Systems (GNSS) disruptions. This study employed three year data (2007-2009) from Magnetic Data Acquisition System (MAGDAS) facilities at six (6) observatories along the 210o magnetic meridian (MM) for investigating hourly, seasonal and annual variations in the horizontal  component of the Earth’s magnetic field. The baseline value of H was computed from its average value near local midnight hours between 2400 and 0100 local time (LT) and subtracted from other hours value for the hourly variation; while the monthly and annual averages were computed for seasonal and yearly analysis respectively. Results indicates that maximum values of Sq are recorded in equinoctial season with an annual peak value of 70.96 nT for year 2009 recorded at Langkawi (LKW) as against the lowest peak value of 27.45 nT recorded in Cooktown (CKT) at 1300LT. Keywords: Magnetic field, horizontal component, solar quiet, seasonal variation, solar equino

The graft copolymerisation of acrylamide onto cellulose using enhanced Fe2+ / H2O2 redox initiator system

Graft copolymers of acrylamide onto holocellulose derived from cocoa (Theobroma cacao) wood meal have been produced using hydroquinone enhanced Fe2+/H2O2 redox system. The addition of hydroquinone to the redox system affected the effectiveness of the redox system to initiate graft copolymer formation. The effects of time, monomer concentration, initiator concentration, and temperature were studied to determine the optimum condition for graft copolymer formation. Journal of Applied Sciences and Environmental Management Vol. 10(3) 2006: 151-15

The use and economic benefits of fibres from sisal hemp (Agave sisalana) leaves as supporting ropes for fishing gear

Sisal hemp (Agave sisalana) leaves were harvested and processed using the beating and decomposition methods. The fibres obtained were washed, dried and finally spurned in to cordage of about 4mm diameter 39 pieces of ropes, each measuring 2 meters were altogether spurned. 30 pieces of these ropes were immersed in water for a period of 24 weeks, 6 were placed in a shaded and airily place and 3 were used for the head and footling of gillnet, sinker line of cast net and the main line of long line. Every other week, the ropes in water and air were tested for its breaking strength using an improved 50kg spring balance. At the end of the experiment, it was found the immersed ropes maintained a tensile strength of over 50kg/F for the first 18 weeks, thereafter; there was a gradual weekly reduction in the strength until the 23rd week when the tensile strength was less than 1kg/F. The cost benefit analysis showed that about 5,3146 tons processed fibers could be obtained fro 1ha. capable of being spenced in to 528300m of 4mm diameter cordage. This paper finally recommended the growth of sisal hemp plants by fisher folks so that there will be constant stock for intermittent harvesting for rope spurnin

Studying the Characteristics of Polystyrene- Modified Cocoa (Theobroma cacao) Wood Cellulose Acetate Membrane

In this work, cellulose was obtained from cocoa wood (Theobroma cacao) by the chlorite pulping process. The harnessed cellulose was acetylated by the process of step-wise acetylation to a degree of acetylation (DA) of 2.06. Ten percent (10%) solution of the acetylated cellulose material in acetone was used to cast membrane. Polystyrene was used to modify the cellulose acetate and was also used to cast membranes. The modified and unmodified membranes were characterized in terms of their salt rejection capacity, extent of dissolved solid (DS) removal, fold endurance, water permeability, swellability in organic liquids and organic liquid separation potentials. The modification of the cellulose acetate with polystyrene increased its potential for salt rejection by 91.10%, dissolved solid (DS) removal by 98.06, fold endurance by 100%, but decreased its permeability to water by 10%. The result of the permeation test for organic solvents showed a variation in the permeation rate of the organic liquids ranging from 6.08x10-4molcm-2sec-1 for hexane, to 9.67x10-4molcm-2sec-1 for ethanol. Overall, the modification of the cocoa wood cellulose acetate membrane with polystyrene has led to improvement of properties.Keywords: cellulose acetate, cocoa wood, membrane, modified, polystyrene

Development of Automatic Switch using PIR and SSR for Day and Night Detection

None conservative attitude is observed among the African people in non-conservative utilization of public power supply. Individuals are often observed power on the lightings, cooling systems when not needed at homes, offices and commercial centers. This increases power bills and may hinders a nation from diverting power to industrial areas, limiting the process of industrialization and waste of energy. To avert these, this paper presents development of automatic switch using passive infrared sensor (PIR) and solid state relay (SSR) for day and night detection. The objective of this project is to replace the electromagnetic relays which may fail as a result of carbon forming resulting from arching in existing designs with solid state relay. Also, the system is to conserve energy more by ensuring that bulbs are not powered on during the day time except in cases of darkness. The circuit was designed using components such as; power supply, PIR sensor, Light Dependent resistor (LDR) sensor, Microcontroller and SSR, as showed in the circuit figures 1 and 8. The system is achieved using PIC16f628 which is programmed using Micro-C, SSR for switching, PIR for human detection and LDR to detect night and day. The system was tested and worked perfectly. It helped to conserve energy

Characterization of the geomagnetic H-component for a paired station in Africa

This scientific research investigates the quiet days variation, Sq(H) of H- component of geomagnetic field for the paired stations: Aswan (ASW: G.G.Lat.24.090N, G.G.Lon.32.890E and G.M.Lat.15.200, G.M.Lon.104.240),Durban (DRB: G.G.Lat.29.860S, G.G.Lon.31.020E and G.M.Lat.39.210, G.M.Lon.96.10) located along the 960 MM (magnetic meridian) using the ten international quietest days’ geomagnetic data from MAGDAS for the year 2009 (a low activity year).The study reveals that sq(H) shows predominantly the diurnal, monthly and seasonal variations of the geomagnetic H-component during the quiet days year round. With maximum amplitude of sq(H) in ASW and minimum in DRB. Meanwhile, the CEJ seen as negative depressions in the H-component of earth field at DRB are all salient physical processes in this study. Further data analysis also revealed many other interesting characteristics for the Sq(H) over African sector paired station. The conclusion drawn from the study shows that the geomagnetic field variations in the northern hemisphere are higher due to solar activities in the region. The Northern Hemisphere is tilted toward the sun, so this area of the Earth receives more direct sunlight during the day than the Southern Hemisphere does. The Southern Hemisphere, on the other hand, is tilted away from the sun and thus receives the sun's rays at an angle, which significantly explains why there is a consistent decrease when it reaches the Durban station (southern hemisphere station), hence the solar activity of the sun influences the Earth’s magnetic field, and the upper atmosphere(ionosphere)

Geomagnetic Field Variations from some Equatorial Electrojet Stations

Abstract.Quiet day variations of the equatorial electrojet along the dip equator from 10 MAGDAS stations show that there could be substantial day to day variability in the electrojet (EEJ) strength. Variations of greater than 80 nT are found in pairs of stations on the same day. The analyses show that the correlation between pairs of stations decreases as a function of increasing distance between them. The results confirm the presence of counter electrojet occurring mainly in the morning and evening hours with strengths of up to 30 nT in certain instances. The data show a longitudinal variability in the EEJ, with results showing strongest EEJ current in the South American sector and weakest in the Malaysian sector

Latitudinal and Seasonal Investigations of Storm-Time TEC Variation

The ionosphere responds markedly and unpredictably to varying magnetospheric energy inputs caused by solar disturbances on the geospace. Knowledge of the impact of the space weather events on the ionosphere is important to assess the environmental effect on the operations of ground- and space-based technologies. Thus, global positioning system (GPS) measurements from the international GNSS service (IGS) database were used to investigate the ionospheric response to 56 geomagnetic storm events at six different latitudes comprising the northern and southern hemispheres in the Afro-European sector. Statistical distributions of total electron content (TEC) response show that during the main phase of the storms, enhancement of TEC is more pronounced in most of the seasons, regardless of the latitude and hemisphere. However, a strong seasonal dependence appears in the TEC response during the recovery phase. Depletion of TEC is majorly observed at the high latitude stations, and its appearance at lower latitudes is seasonally dependent. In summer hemisphere, the depletion of TEC is more pronounced in nearly all the latitudinal bands. In winter hemisphere, enhancement as well as depletion of TEC is observed over the high latitude, while enhancement is majorly observed over the mid and low latitudes. In equinoxes, the storm-time TEC distribution shows a fairly consistent characteristic with the summer distribution, particularly in the northern hemisphere

Dual Functional Copper (II) Isophthalate Coordination Polymer for Selective Sensing of Fe3+ Ions and Methanol

Fluorescent chemosensors are becoming attractive due to their unique features of sensitivity and selective detection of analytes in the aqueous and vapour phases. Inorganic and organic pollutants are of major concern because of their adverse health effects. In this work, a coordination compound [Cu(ISO)2(H2O)2]·DMF 1 (where H2ISO = 2,4-benzenedicarboxylic acid) was synthesized by oven-heating at 100 °C. Compound 1 was characterized using elemental analysis, UV/Visible and Fourier transform infrared (FTIR) spectroscopies, Thermogravimetric analysis (TGA), and Scanning Electron Microscopy (SEM). The compound is thermally stable up to 356 °C. Compound 1 showed excellent fluorescent properties with emission centred at 435 nm. This is attributed to ligand to metal charge transfer (LMCT) arising from the π-electron rich backbone of the free ligand. The compound was further studied for detection of metal cation and volatile organic compounds (VOCs). Results show selective recognition of Fe3+ ions and methanol by drastic quenching of fluorescent intensity. High Stern Volmer constants and low limits of detection makes the compound a viable material for ion and vapour detection